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Sample records for standardized low-resolution brain

  1. Source localization of intermittent rhythmic delta activity in a patient with acute confusional migraine: cross-spectral analysis using standardized low-resolution brain electromagnetic tomography (sLORETA).

    PubMed

    Kim, Dae-Eun; Shin, Jung-Hyun; Kim, Young-Hoon; Eom, Tae-Hoon; Kim, Sung-Hun; Kim, Jung-Min

    2016-01-01

    Acute confusional migraine (ACM) shows typical electroencephalography (EEG) patterns of diffuse delta slowing and frontal intermittent rhythmic delta activity (FIRDA). The pathophysiology of ACM is still unclear but these patterns suggest neuronal dysfunction in specific brain areas. We performed source localization analysis of IRDA (in the frequency band of 1-3.5 Hz) to better understand the ACM mechanism. Typical IRDA EEG patterns were recorded in a patient with ACM during the acute stage. A second EEG was obtained after recovery from ACM. To identify source localization of IRDA, statistical non-parametric mapping using standardized low-resolution brain electromagnetic tomography was performed for the delta frequency band comparisons between ACM attack and non-attack periods. A difference in the current density maximum was found in the dorsal anterior cingulated cortex (ACC). The significant differences were widely distributed over the frontal, parietal, temporal and limbic lobe, paracentral lobule and insula and were predominant in the left hemisphere. Dorsal ACC dysfunction was demonstrated for the first time in a patient with ACM in this source localization analysis of IRDA. The ACC plays an important role in the frontal attentional control system and acute confusion. This dysfunction of the dorsal ACC might represent an important ACM pathophysiology. PMID:26292789

  2. Low resolution brain electromagnetic tomography in a realistic geometry head model: a simulation study

    NASA Astrophysics Data System (ADS)

    Ding, Lei; Lai, Yuan; He, Bin

    2005-01-01

    It is of importance to localize neural sources from scalp recorded EEG. Low resolution brain electromagnetic tomography (LORETA) has received considerable attention for localizing brain electrical sources. However, most such efforts have used spherical head models in representing the head volume conductor. Investigation of the performance of LORETA in a realistic geometry head model, as compared with the spherical model, will provide useful information guiding interpretation of data obtained by using the spherical head model. The performance of LORETA was evaluated by means of computer simulations. The boundary element method was used to solve the forward problem. A three-shell realistic geometry (RG) head model was constructed from MRI scans of a human subject. Dipole source configurations of a single dipole located at different regions of the brain with varying depth were used to assess the performance of LORETA in different regions of the brain. A three-sphere head model was also used to approximate the RG head model, and similar simulations performed, and results compared with the RG-LORETA with reference to the locations of the simulated sources. Multi-source localizations were discussed and examples given in the RG head model. Localization errors employing the spherical LORETA, with reference to the source locations within the realistic geometry head, were about 20-30 mm, for four brain regions evaluated: frontal, parietal, temporal and occipital regions. Localization errors employing the RG head model were about 10 mm over the same four brain regions. The present simulation results suggest that the use of the RG head model reduces the localization error of LORETA, and that the RG head model based LORETA is desirable if high localization accuracy is needed.

  3. Three-Dimensional Electroencephalographic Changes on Low-Resolution Brain Electromagnetic Tomography (LORETA) During the Sleep Onset Period.

    PubMed

    Park, Doo-Heum; Ha, Jee Hyun; Ryu, Seung-Ho; Yu, Jaehak; Shin, Chul-Jin

    2015-10-01

    Electroencephalographic (EEG) patterns during sleep are markedly different from those measured during the waking state, but the process of falling asleep is not fully understood in terms of biochemical and neurophysiological aspects. We sought to investigate EEG changes that occur during the transitional period from wakefulness to sleep in a 3-dimensional manner to gain a better understanding of the physiological meaning of sleep for the brain. We examined EEG 3-dimensionally using LORETA (low-resolution electromagnetic tomography), to localize the brain region associated with changes that occur during the sleep onset period (SOP). Thirty-channel EEG was recorded in 61 healthy subjects. EEG power spectra and intracortical standardized LORETA were compared between 4 types of 30-second states, including the wakeful stage, transition stage, early sleep stage 1, and late sleep stage 1. Sleep onset began with increased delta and theta power and decreased alpha-1 power in the occipital lobe, and increased theta power in the parietal lobe. Thereafter, global reductions of alpha-1 and alpha-2 powers and greater increases of theta power in the occipito-parietal lobe occurred. As sleep became deeper in sleep stage 1, beta-2 and beta-3, powers decreased mainly in the frontal lobe and some regions of the parieto-temporo-limbic area. These findings suggest that sleep onset includes at least 3 steps in a sequential manner, which include an increase in theta waves in the posterior region of the brain, a global decrease in alpha waves, and a decrease in beta waves in the fronto-central area. PMID:25150221

  4. Prediction of Treatment Outcome in Patients with Obsessive-Compulsive Disorder with Low-Resolution Brain Electromagnetic Tomography: A Prospective EEG Study

    PubMed Central

    Krause, Daniela; Folkerts, Malte; Karch, Susanne; Keeser, Daniel; Chrobok, Agnieszka I.; Zaudig, Michael; Hegerl, Ulrich; Juckel, Georg; Pogarell, Oliver

    2016-01-01

    The issue of predicting treatment response and identifying, in advance, which patient will profit from treating obsessive-compulsive disorder (OCD) seems to be an elusive goal. This prospective study investigated brain electric activity [using Low-Resolution Brain Electromagnetic Tomography (LORETA)] for the purpose of predicting response to treatment. Forty-one unmedicated patients with a DSM-IV diagnosis of OCD were included. A resting 32-channel EEG was obtained from each participant before and after 10 weeks of standardized treatment with sertraline and behavioral therapy. LORETA was used to localize the sources of brain electrical activity. At week 10, patients were divided into responders and non-responders (according to a reduction of symptom severity >50% on the Y-BOCS). LORETA analysis revealed that at baseline responders showed compared to non-responders a significantly lower brain electric activity within the beta 1 (t = 2.86, p < 0.05), 2 (t = 2.81, p < 0.05), and 3 (t = 2.76, p < 0.05) frequency bands and ROI analysis confirmed a reduced activity in alpha 2 (t = 2.06, p < 0.05) in the anterior cingulate cortex (ACC). When baseline LORETA data were compared to follow-up data, the analysis showed in the responder group a significantly lower brain electrical resting activity in the beta 1 (t = 3.17. p < 0.05) and beta 3 (t = 3.11. p < 0.05) frequency bands and equally for the ROI analysis of the orbitofrontal cortex (OFC) in the alpha 2 (t = 2.15. p < 0.05) frequency band. In the group of non-responders the opposite results were found. In addition, a positive correlation between frequency alpha 2 (rho = 0.40, p = 0.010), beta 3 (rho = 0.42, p = 0.006), delta (rho = 0.33, p = 0.038), theta (rho = 0.34, p = 0.031), alpha 1 (rho = 0.38, p = 0.015), and beta1 (rho = 0.34, p = 0.028) of the OFC and the bands delta (rho = 0.33, p = 0.035), alpha 1 (rho = 0.36, p = 0.019), alpha 2 (rho = 0.34, p = 0.031), and beta 3 (rho = 0.38, p = 0.015) of the ACC with a reduction of the Y-BOCS scores was identified. Our results suggest that measuring brain activity with LORETA could be an efficient and applicable technique to prospectively identify treatment responders in OCD. PMID:26834658

  5. Effects of the South American psychoactive beverage ayahuasca on regional brain electrical activity in humans: a functional neuroimaging study using low-resolution electromagnetic tomography.

    PubMed

    Riba, Jordi; Anderer, Peter; Jané, Francesc; Saletu, Bernd; Barbanoj, Manel J

    2004-01-01

    Ayahuasca, a South American psychotropic plant tea obtained from Banisteriopsis caapi and Psychotria viridis, combines monoamine oxidase-inhibiting beta-carboline alkaloids with N,N-dimethyltryptamine (DMT), a psychedelic agent showing 5-HT(2A) agonist activity. In a clinical research setting, ayahuasca has demonstrated a combined stimulatory and psychedelic effect profile, as measured by subjective effect self-assessment instruments and dose-dependent changes in spontaneous brain electrical activity, which parallel the time course of subjective effects. In the present study, the spatial distribution of ayahuasca-induced changes in brain electrical activity was investigated by means of low-resolution electromagnetic tomography (LORETA). Electroencephalography recordings were obtained from 18 volunteers after the administration of a dose of encapsulated freeze-dried ayahuasca containing 0.85 mg DMT/kg body weight and placebo. The intracerebral power density distribution was computed with LORETA from spectrally analyzed data, and subjective effects were measured by means of the Hallucinogen Rating Scale (HRS). Statistically significant differences compared to placebo were observed for LORETA power 60 and 90 min after dosing, together with increases in all six scales of the HRS. Ayahuasca decreased power density in the alpha-2, delta, theta and beta-1 frequency bands. Power decreases in the delta, alpha-2 and beta-1 bands were found predominantly over the temporo-parieto-occipital junction, whereas theta power was reduced in the temporomedial cortex and in frontomedial regions. The present results suggest the involvement of unimodal and heteromodal association cortex and limbic structures in the psychological effects elicited by ayahuasca. PMID:15179026

  6. IRAS Low Resolution Spectra of Asteroids

    NASA Technical Reports Server (NTRS)

    Cohen, Martin; Walker, Russell G.

    2002-01-01

    Optical/near-infrared studies of asteroids are based on reflected sunlight and surface albedo variations create broad spectral features, suggestive of families of materials. There is a significant literature on these features, but there is very little work in the thermal infrared that directly probes the materials emitting on the surfaces of asteroids. We have searched for and extracted 534 thermal spectra of 245 asteroids from the original Dutch (Groningen) archive of spectra observed by the IRAS Low Resolution Spectrometer (LRS). We find that, in general, the observed shapes of the spectral continua are inconsistent with that predicted by the standard thermal model used by IRAS. Thermal models such as proposed by Harris (1998) and Harris et al.(1998) for the near-earth asteroids with the "beaming parameter" in the range of 1.0 to 1.2 best represent the observed spectral shapes. This implies that the IRAS Minor Planet Survey (IMPS, Tedesco, 1992) and the Supplementary IMPS (SIMPS, Tedesco, et al., 2002) derived asteroid diameters are systematically underestimated, and the albedos are overestimated. We have tentatively identified several spectral features that appear to be diagnostic of at least families of materials. The variation of spectral features with taxonomic class hints that thermal infrared spectra can be a valuable tool for taxonomic classification of asteroids.

  7. Low Resolution Picture Transmission (LRPT) Demonstration System

    NASA Technical Reports Server (NTRS)

    Fong, Wai; Yeh, Pen-Shu; Sank, Victor; Nyugen, Xuan; Xia, Wei; Duran, Steve; Day, John H. (Technical Monitor)

    2002-01-01

    Low-Resolution Picture Transmission (LRPT) is a proposed standard for direct broadcast transmission of satellite weather images. This standard is a joint effort by the European Organization for the Exploitation of Meteorological Satellites (EUMETSAT) and the National Oceanic Atmospheric Administration (NOAA). As a digital transmission scheme, its purpose is to replace the current analog Automatic Picture Transmission (APT) system for use in the Meteorological Operational (METOP) satellites. Goddard Space Flight Center has been tasked to build an LRPT Demonstration System (LDS). It's main objective is to develop or demonstrate the feasibility of a low-cost receiver utilizing a Personal Computer (PC) as the primary processing component and determine the performance of the protocol in the simulated Radio Frequency (RF) environment. The approach would consist of two phases. In the phase 1, a Commercial-off-the-Shelf (COTS) Modulator-Demodulator (MODEM) board that would perform RF demodulation would be purchased allowing the Central Processing Unit (CPU) to perform the Consultative Committee for Space Data Systems (CCSDS) protocol processing. Also since the weather images are compressed the PC would perform the decompression. Phase 1 was successfully demonstrated on December 1997. Phase 2 consists of developing a high-fidelity receiver, transmitter and environment simulator. Its goal is to find out how the METOP Specification performs in a simulated noise environment in a cost-effective receiver. The approach would be to produce a receiver using as much software as possible to perform front-end processing to take advantage of the latest high-speed PCs. Thus the COTS MODEM used in Phase 1 is performing RF demodulation along with data acquisition providing data to the receiving software. Also, environment simulator is produced using the noise patterns generated by Institute for Telecommunications Sciences (ITS) from their noise environment study.

  8. Brain-Based Learning and Standards-Based Elementary Science.

    ERIC Educational Resources Information Center

    Konecki, Loretta R.; Schiller, Ellen

    This paper explains how brain-based learning has become an area of interest to elementary school science teachers, focusing on the possible relationships between, and implications of, research on brain-based learning to the teaching of science education standards. After describing research on the brain, the paper looks at three implications from…

  9. Standardizing Data Collection in Traumatic Brain Injury

    PubMed Central

    Harrison-Felix, Cynthia L.; Menon, David; Adelson, P. David; Balkin, Tom; Bullock, Ross; Engel, Doortje C.; Gordon, Wayne; Langlois-Orman, Jean; Lew, Henry L.; Robertson, Claudia; Temkin, Nancy; Valadka, Alex; Verfaellie, Mieke; Wainwright, Mark; Wright, David W.; Schwab, Karen

    2011-01-01

    Abstract Collaboration among investigators, centers, countries, and disciplines is essential to advancing the care for traumatic brain injury (TBI). It is thus important that we “speak the same language.” Great variability, however, exists in data collection and coding of variables in TBI studies, confounding comparisons between and analysis across different studies. Randomized controlled trials can never address the many uncertainties concerning treatment approaches in TBI. Pooling data from different clinical studies and high-quality observational studies combined with comparative effectiveness research may provide excellent alternatives in a cost-efficient way. Standardization of data collection and coding is essential to this end. Common data elements (CDEs) are presented for demographics and clinical variables applicable across the broad spectrum of TBI. Most recommendations represent a consensus derived from clinical practice. Some recommendations concern novel approaches, for example assessment of the intensity of therapy in severely injured patients. Up to three levels of detail for coding data elements were developed: basic, intermediate, and advanced, with the greatest level of detail attained in the advanced version. More detailed codings can be collapsed into the basic version. Templates were produced to summarize coding formats, explanation of choices, and recommendations for procedures. Endorsement of the recommendations has been obtained from many authoritative organizations. The development of CDEs for TBI should be viewed as a continuing process; as more experience is gained, refinement and amendments will be required. This proposed process of standardization will facilitate comparative effectiveness research and encourage high-quality meta-analysis of individual patient data. PMID:21162610

  10. Image enhancement for low resolution display panels

    NASA Astrophysics Data System (ADS)

    Kothari, Rakshit S.; Saber, Eli; Nelson, Marvin; Stauffer, Michael; Bohan, Dave

    2015-01-01

    This paper presents a real time automatic image correction technique operating under real-time constraints (25ms) to address red dot artifacts in low resolution display panels. The algorithm is designed as a two stage process, starting with the identification of pixels which could cause such artifacts followed by a color correction scheme to compensate for any perceived visual errors. Artifact inducing pixels are identified by thresholding the vector color gradient of the image. The color levels of the adjacent subpixels around the artifacts are estimated based on partitive spatial color mixing. Red dot artifacts occur as singlet, couplets or triplets and consequently three different correction schemes are explored. The algorithm also ensures that artifacts occurring at junctions, corners and cross sections are corrected without affecting the underlying shape or contextual sharpness. The performance of our algorithm was benchmarked using a series of 30 corrected and uncorrected images by human observers. This algorithm is designed as a general purpose color correction technique for display panels with an offset in their subpixel patterns and can be easily implemented as an isolated real time post processing technique for the output display buffer without any higher order processing or image content information. All the above mentioned benefits are realized through software and don't require any upgrade or replacement of existing hardware.

  11. The LAMOST low resolution spectrograph stability performance

    NASA Astrophysics Data System (ADS)

    Hou, YongHui; Wang, Lei; Hu, Zhongwen; Wang, Jianing; Tang, Zhen; Jiang, Mingda; Zhu, Yongtian

    2012-09-01

    One of the Large Sky Area Multi-Object Spectroscopic Telescope (LAMOST) scientific requirements require the ability of the low resolution spectrograph(LRS) to measure velocities to a accuracy of 4km/s over the entire 5 degree field in 2 hours objects observation. This requirement results in the specification of image movement less than 0.6?m/hours (0.05pixl/hours corresponding to the science detector).There are 16 spectrographs for LAMOST telescope, so we expect the design aspects of the instrument directed towards achieving the stability goal. In this paper we present the last design aspects of the instrument which enable meeting the 4km/s requirement, and the recent test results of the LRS's Stability Performance. The test results show that the stability performance of LAMOST-LRS can meet the the stability goal, the image shift along the direction of dispersion is not influenced by the external factors, and the image shift along vertical dispersion direction meet the technical requirements when the environmental temperature of the spectrograph room is in control.

  12. Deformable elastic network refinement for low-resolution macromolecular crystallography

    SciTech Connect

    Schröder, Gunnar F.; Levitt, Michael; Brunger, Axel T.

    2014-09-01

    An overview of applications of the deformable elastic network (DEN) refinement method is presented together with recommendations for its optimal usage. Crystals of membrane proteins and protein complexes often diffract to low resolution owing to their intrinsic molecular flexibility, heterogeneity or the mosaic spread of micro-domains. At low resolution, the building and refinement of atomic models is a more challenging task. The deformable elastic network (DEN) refinement method developed previously has been instrumental in the determinion of several structures at low resolution. Here, DEN refinement is reviewed, recommendations for its optimal usage are provided and its limitations are discussed. Representative examples of the application of DEN refinement to challenging cases of refinement at low resolution are presented. These cases include soluble as well as membrane proteins determined at limiting resolutions ranging from 3 to 7 Å. Potential extensions of the DEN refinement technique and future perspectives for the interpretation of low-resolution crystal structures are also discussed.

  13. A super resolution framework for low resolution document image OCR

    NASA Astrophysics Data System (ADS)

    Ma, Di; Agam, Gady

    2013-01-01

    Optical character recognition is widely used for converting document images into digital media. Existing OCR algorithms and tools produce good results from high resolution, good quality, document images. In this paper, we propose a machine learning based super resolution framework for low resolution document image OCR. Two main techniques are used in our proposed approach: a document page segmentation algorithm and a modified K-means clustering algorithm. Using this approach, by exploiting coherence in the document, we reconstruct from a low resolution document image a better resolution image and improve OCR results. Experimental results show substantial gain in low resolution documents such as the ones captured from video.

  14. Robust Intensity Standardization in Brain Magnetic Resonance Images.

    PubMed

    De Nunzio, Giorgio; Cataldo, Rosella; Carlà, Alessandra

    2015-12-01

    The paper is focused on a tiSsue-Based Standardization Technique (SBST) of magnetic resonance (MR) brain images. Magnetic Resonance Imaging intensities have no fixed tissue-specific numeric meaning, even within the same MRI protocol, for the same body region, or even for images of the same patient obtained on the same scanner in different moments. This affects postprocessing tasks such as automatic segmentation or unsupervised/supervised classification methods, which strictly depend on the observed image intensities, compromising the accuracy and efficiency of many image analyses algorithms. A large number of MR images from public databases, belonging to healthy people and to patients with different degrees of neurodegenerative pathology, were employed together with synthetic MRIs. Combining both histogram and tissue-specific intensity information, a correspondence is obtained for each tissue across images. The novelty consists of computing three standardizing transformations for the three main brain tissues, for each tissue class separately. In order to create a continuous intensity mapping, spline smoothing of the overall slightly discontinuous piecewise-linear intensity transformation is performed. The robustness of the technique is assessed in a post hoc manner, by verifying that automatic segmentation of images before and after standardization gives a high overlapping (Dice index >0.9) for each tissue class, even across images coming from different sources. Furthermore, SBST efficacy is tested by evaluating if and how much it increases intertissue discrimination and by assessing gaussianity of tissue gray-level distributions before and after standardization. Some quantitative comparisons to already existing different approaches available in the literature are performed. PMID:25708893

  15. Low-resolution optimized 3D-subband scalable codec

    NASA Astrophysics Data System (ADS)

    Bourge, Arnaud; Barrau, Eric

    2003-05-01

    Today, 3D subband (3DS) video coding schemes are close to current standard solutions in terms of coding efficiency while they add the scalability functionality through embedded bitstreams. Spatial scalability may be regarded as a key-feature brought by such codecs, enabling adaptation to varying terminal capabilities and display sizes. However, this functionality still suffers from a lack of coding efficiency when motion compensation is used. Though enabling motion compensation at the temporal filtering stage dramatically improves energy compaction, it generates a strong motion vector overhead and introduces a reconstruction drift when decoding at lower spatial resolutions. This is because the Discrete Wavelet Transform and the motion compensation (MC) are not commutative. Some authors solve this problem by transmitting the drift signal as side information, but this increases the bit-rate. In this paper we present a low-resolution optimized MC-3DS scalable codec with no drift, that does not generate any overhead. Its structure is fully compliant with any subband-tree entropy encoder and preserves all the other scalability functions (temporal and SNR). Tests and simulations show that the new scheme remains quite efficient when decoding at full resolution, while it outperforms the previous solution as far as spatial scalability is concerned, especially with high-activity sequences.

  16. High Resolution MOS Forecasts Based on a Low Resolution Model

    NASA Astrophysics Data System (ADS)

    Knüpffer, K.

    2009-09-01

    MOS (Model Output Statistics) reduces approximately 50% of the error variance of the Direct Model Output forecasts of a numerical model - no matter whether high or low resolution - for standard weather elements like temperatures, wind and cloud cover. However, MOS forecasts are usually only provided at the very places where the observation locations are situated. In the presentation, a technology will be outlined which allows MOS forecasts for any location between the observation locations. Meteo Service has introduced a technology which relies on the interpolation of MOS coefficients (not MOS forecasts). This technology based on orographic descriptors has already been in use with the German National Weather Service (DWD) since 1996. These orographic descriptors refer to latitude, longitude, elevation and the difference between the elevation of the smoothed model orography, and the real elevation. This difference is used in order to distinguish between mountain and valley. In addition, an attribute such as land, sea, coast and mountain summits has been used as binary orographic descriptor. Nowadays high resolution grid information is available, and more complex orographic descriptors can be used. NOAA/NGDC orographic data is available in a resolution of approximately 0,5 x 0,5 km and allows for the definition of the following orographic descriptors with different spatial smoothing: - elevation - slope (= first derivative of elevation) - valley/hill (= second derivative of elevation). A difference between the weighted orographic desriptors is used to define the representativeness between interpolation points and observation locations. This representativeness is the norm of a multi-dimensional vector with the number of dimensions being equal to the number of orographic descriptors. A procedure to search for the most informative set of representative observation locations for a given interpolation point is applied. Finally interpolation weights are calculated for the selected observation locations. Results of the application of the concept of coefficient interpolation outlined above are presented using MOS forecasts for homogeneous, alpine and coastal orography. The results are convincing in particular, in areas where there is sufficient density of observation locations. Problems remain in areas with lower density of observation locations and complex orography. Interpolated Direct Model Output in the last resort is to be used in order to achieve complete fields of high resolution MOS forecasts based on a low resolution model.

  17. Cyberinfrastructure for the digital brain: spatial standards for integrating rodent brain atlases.

    PubMed

    Zaslavsky, Ilya; Baldock, Richard A; Boline, Jyl

    2014-01-01

    Biomedical research entails capture and analysis of massive data volumes and new discoveries arise from data-integration and mining. This is only possible if data can be mapped onto a common framework such as the genome for genomic data. In neuroscience, the framework is intrinsically spatial and based on a number of paper atlases. This cannot meet today's data-intensive analysis and integration challenges. A scalable and extensible software infrastructure that is standards based but open for novel data and resources, is required for integrating information such as signal distributions, gene-expression, neuronal connectivity, electrophysiology, anatomy, and developmental processes. Therefore, the International Neuroinformatics Coordinating Facility (INCF) initiated the development of a spatial framework for neuroscience data integration with an associated Digital Atlasing Infrastructure (DAI). A prototype implementation of this infrastructure for the rodent brain is reported here. The infrastructure is based on a collection of reference spaces to which data is mapped at the required resolution, such as the Waxholm Space (WHS), a 3D reconstruction of the brain generated using high-resolution, multi-channel microMRI. The core standards of the digital atlasing service-oriented infrastructure include Waxholm Markup Language (WaxML): XML schema expressing a uniform information model for key elements such as coordinate systems, transformations, points of interest (POI)s, labels, and annotations; and Atlas Web Services: interfaces for querying and updating atlas data. The services return WaxML-encoded documents with information about capabilities, spatial reference systems (SRSs) and structures, and execute coordinate transformations and POI-based requests. Key elements of INCF-DAI cyberinfrastructure have been prototyped for both mouse and rat brain atlas sources, including the Allen Mouse Brain Atlas, UCSD Cell-Centered Database, and Edinburgh Mouse Atlas Project. PMID:25309417

  18. Cyberinfrastructure for the digital brain: spatial standards for integrating rodent brain atlases

    PubMed Central

    Zaslavsky, Ilya; Baldock, Richard A.; Boline, Jyl

    2014-01-01

    Biomedical research entails capture and analysis of massive data volumes and new discoveries arise from data-integration and mining. This is only possible if data can be mapped onto a common framework such as the genome for genomic data. In neuroscience, the framework is intrinsically spatial and based on a number of paper atlases. This cannot meet today's data-intensive analysis and integration challenges. A scalable and extensible software infrastructure that is standards based but open for novel data and resources, is required for integrating information such as signal distributions, gene-expression, neuronal connectivity, electrophysiology, anatomy, and developmental processes. Therefore, the International Neuroinformatics Coordinating Facility (INCF) initiated the development of a spatial framework for neuroscience data integration with an associated Digital Atlasing Infrastructure (DAI). A prototype implementation of this infrastructure for the rodent brain is reported here. The infrastructure is based on a collection of reference spaces to which data is mapped at the required resolution, such as the Waxholm Space (WHS), a 3D reconstruction of the brain generated using high-resolution, multi-channel microMRI. The core standards of the digital atlasing service-oriented infrastructure include Waxholm Markup Language (WaxML): XML schema expressing a uniform information model for key elements such as coordinate systems, transformations, points of interest (POI)s, labels, and annotations; and Atlas Web Services: interfaces for querying and updating atlas data. The services return WaxML-encoded documents with information about capabilities, spatial reference systems (SRSs) and structures, and execute coordinate transformations and POI-based requests. Key elements of INCF-DAI cyberinfrastructure have been prototyped for both mouse and rat brain atlas sources, including the Allen Mouse Brain Atlas, UCSD Cell-Centered Database, and Edinburgh Mouse Atlas Project. PMID:25309417

  19. Automatic corpus callosum segmentation for standardized MR brain scanning

    NASA Astrophysics Data System (ADS)

    Xu, Qing; Chen, Hong; Zhang, Li; Novak, Carol L.

    2007-03-01

    Magnetic Resonance (MR) brain scanning is often planned manually with the goal of aligning the imaging plane with key anatomic landmarks. The planning is time-consuming and subject to inter- and intra- operator variability. An automatic and standardized planning of brain scans is highly useful for clinical applications, and for maximum utility should work on patients of all ages. In this study, we propose a method for fully automatic planning that utilizes the landmarks from two orthogonal images to define the geometry of the third scanning plane. The corpus callosum (CC) is segmented in sagittal images by an active shape model (ASM), and the result is further improved by weighting the boundary movement with confidence scores and incorporating region based refinement. Based on the extracted contour of the CC, several important landmarks are located and then combined with landmarks from the coronal or transverse plane to define the geometry of the third plane. Our automatic method is tested on 54 MR images from 24 patients and 3 healthy volunteers, with ages ranging from 4 months to 70 years old. The average accuracy with respect to two manually labeled points on the CC is 3.54 mm and 4.19 mm, and differed by an average of 2.48 degrees from the orientation of the line connecting them, demonstrating that our method is sufficiently accurate for clinical use.

  20. New carbon stars identified from low-resolution IRAS spectra

    NASA Astrophysics Data System (ADS)

    Little-Marenin, I. R.; Ramsay, M. E.; Stephenson, C. B.; Little, S. J.; Price, S. D.

    1987-03-01

    The authors have classified 176 IRAS sources as carbon stars based on the presence of the SiC emission feature at 11.2 micron in their low-resolution spectra (LRS). The right ascension and declination, the LRS characterization, and the quality of the two halves of the LRS spectra are shown for each source. Associations with other catalogs are also given.

  1. Human Mobility Monitoring in Very Low Resolution Visual Sensor Network

    PubMed Central

    Bo Bo, Nyan; Deboeverie, Francis; Eldib, Mohamed; Guan, Junzhi; Xie, Xingzhe; Niño, Jorge; Van Haerenborgh, Dirk; Slembrouck, Maarten; Van de Velde, Samuel; Steendam, Heidi; Veelaert, Peter; Kleihorst, Richard; Aghajan, Hamid; Philips, Wilfried

    2014-01-01

    This paper proposes an automated system for monitoring mobility patterns using a network of very low resolution visual sensors (30 × 30 pixels). The use of very low resolution sensors reduces privacy concern, cost, computation requirement and power consumption. The core of our proposed system is a robust people tracker that uses low resolution videos provided by the visual sensor network. The distributed processing architecture of our tracking system allows all image processing tasks to be done on the digital signal controller in each visual sensor. In this paper, we experimentally show that reliable tracking of people is possible using very low resolution imagery. We also compare the performance of our tracker against a state-of-the-art tracking method and show that our method outperforms. Moreover, the mobility statistics of tracks such as total distance traveled and average speed derived from trajectories are compared with those derived from ground truth given by Ultra-Wide Band sensors. The results of this comparison show that the trajectories from our system are accurate enough to obtain useful mobility statistics. PMID:25375754

  2. New low-resolution spectrometer spectra for IRAS sources

    NASA Technical Reports Server (NTRS)

    Volk, Kevin; Kwok, Sun; Stencel, R. E.; Brugel, E.

    1991-01-01

    Low-resolution spectra of 486 IRAS point sources with F sub nu(12 microns) in the range 20-40 Jy are presented. This is part of an effort to extract and classify spectra that were not included in the Atlas of Low-Resolution Spectra and represents an extension of the earlier work by Volk and Cohen which covers sources with F sub nu(12 microns) greater than 40 Jy. The spectra have been examined by eye and classified into nine groups based on the spectral morphology. This new classification scheme is compared with the mechanical classification of the Atlas, and the differences are noted. Oxygen-rich stars of the asymptotic giant branch make up 33 percent of the sample. Solid state features dominate the spectra of most sources. It is found that the nature of the sources as implied by the present spectral classification is consistent with the classifications based on broad-band colors of the sources.

  3. An Analysis of the Automated Meteorological Profiling System Low Resolution Flight Element

    NASA Technical Reports Server (NTRS)

    Leahy, Frank B.; Overbey, B. Glenn

    2003-01-01

    A study was conducted to determine the quality of thermodynamic and wind data measured by or derived from the Low Resolution Flight Element (LRFE) of the Automated Meteorological Profiling System (AMPS). The AMPS LRFE replaced the Meteorological Sounding System (MSS), which was used to provide vertical profiles of thermodynamic and low-resolution wind data in support of spacecraft launch operations at the Cape Canaveral Air Force Station (CCAFS) and NASA Kennedy Space Center (KSC), Florida. Air temperature, relative humidity, and height, which are directly measured by the LRFE, are used to derive air pressure and density. Test flights were conducted where an LRFE sonde and an MSS sonde were attached to the same balloon and the two profiles were compared. MSS data was used as the standard reference data. The objective of the thermodynamic testing was to determine a) if the LRFE met Space Shuttle Program (SSP) accuracy requirements outlined in the Space Shuttle Launch and Landing Program Requirements Document (PRD) and/or, b) if the LRFE met or exceeded MSS data quality. AMPS uses the Global Positioning System (GPS) to determine wind speed and direction. In order to provide a basis for comparison, either an AMPS High Resolution Flight Element (HRFE) or a radar tracked Jimsphere was released simultaneously with each AMPS LRFE at CCAFS. The goal of these tests was to determine if the LRFE wind data met the requirement for low-resolution wind data defined in the Shuttle PRD. Based on the available data, the LRFE is shown to produce more consistent thermodynamic measurements than the MSS. The LRFE is also shown to meet the Shuttle PRD requirements for low resolution wind data.

  4. Peak fitting applied to low-resolution enrichment measurements

    SciTech Connect

    Bracken, D.; McKown, T.; Sprinkle, J.K. Jr.; Gunnink, R.; Kartoshov, M.; Kuropatwinski, J.; Raphina, G.; Sokolov, G.

    1998-12-01

    Materials accounting at bulk processing facilities that handle low enriched uranium consists primarily of weight and uranium enrichment measurements. Most low enriched uranium processing facilities draw separate materials balances for each enrichment handled at the facility. The enrichment measurement determines the isotopic abundance of the {sup 235}U, thereby determining the proper strata for the item, while the weight measurement generates the primary accounting value for the item. Enrichment measurements using the passive gamma radiation from uranium were developed for use in US facilities a few decades ago. In the US, the use of low-resolution detectors was favored because they cost less, are lighter and more robust, and don`t require the use of liquid nitrogen. When these techniques were exported to Europe, however, difficulties were encountered. Two of the possible root causes were discovered to be inaccurate knowledge of the container wall thickness and higher levels of minor isotopes of uranium introduced by the use of reactor returns in the enrichment plants. the minor isotopes cause an increase in the Compton continuum under the 185.7 keV assay peak and the observance of interfering 238.6 keV gamma rays. The solution selected to address these problems was to rely on the slower, more costly, high-resolution gamma ray detectors when the low-resolution method failed. Recently, these gamma ray based enrichment measurement techniques have been applied to Russian origin material. The presence of interfering gamma radiation from minor isotopes was confirmed. However, with the advent of fast portable computers, it is now possible to apply more sophisticated analysis techniques to the low-resolution data in the field. Explicit corrections for Compton background, gamma rays from {sup 236}U daughters, and the attenuation caused by thick containers can be part of the least squares fitting routine. Preliminary results from field measurements in Kazakhstan will be discussed.

  5. Automated lung segmentation of low resolution CT scans of rats

    NASA Astrophysics Data System (ADS)

    Rizzo, Benjamin M.; Haworth, Steven T.; Clough, Anne V.

    2014-03-01

    Dual modality micro-CT and SPECT imaging can play an important role in preclinical studies designed to investigate mechanisms, progression, and therapies for acute lung injury in rats. SPECT imaging involves examining the uptake of radiopharmaceuticals within the lung, with the hypothesis that uptake is sensitive to the health or disease status of the lung tissue. Methods of quantifying lung uptake and comparison of right and left lung uptake generally begin with identifying and segmenting the lung region within the 3D reconstructed SPECT volume. However, identification of the lung boundaries and the fissure between the left and right lung is not always possible from the SPECT images directly since the radiopharmaceutical may be taken up by other surrounding tissues. Thus, our SPECT protocol begins with a fast CT scan, the lung boundaries are identified from the CT volume, and the CT region is coregistered with the SPECT volume to obtain the SPECT lung region. Segmenting rat lungs within the CT volume is particularly challenging due to the relatively low resolution of the images and the rat's unique anatomy. Thus, we have developed an automated segmentation algorithm for low resolution micro-CT scans that utilizes depth maps to detect fissures on the surface of the lung volume. The fissure's surface location is in turn used to interpolate the fissure throughout the lung volume. Results indicate that the segmentation method results in left and right lung regions consistent with rat lung anatomy.

  6. Low-Resolution Raman-Spectroscopy Combustion Thermometry

    NASA Technical Reports Server (NTRS)

    Nguyen, Quang-Viet; Kojima, Jun

    2008-01-01

    A method of optical thermometry, now undergoing development, involves low-resolution measurement of the spectrum of spontaneous Raman scattering (SRS) from N2 and O2 molecules. The method is especially suitable for measuring temperatures in high pressure combustion environments that contain N2, O2, or N2/O2 mixtures (including air). Methods based on SRS (in which scattered light is shifted in wavelength by amounts that depend on vibrational and rotational energy levels of laser-illuminated molecules) have been popular means of probing flames because they are almost the only methods that provide spatially and temporally resolved concentrations and temperatures of multiple molecular species in turbulent combustion. The present SRS-based method differs from prior SRS-based methods that have various drawbacks, a description of which would exceed the scope of this article. Two main differences between this and prior SRS-based methods are that it involves analysis in the frequency (equivalently, wavelength) domain, in contradistinction to analysis in the intensity domain in prior methods; and it involves low-resolution measurement of what amounts to predominantly the rotational Raman spectra of N2 and O2, in contradistinction to higher-resolution measurement of the vibrational Raman spectrum of N2 only in prior methods.

  7. Characterizing Extra-Solar Planets with Low Resolution Spectroscopy

    NASA Astrophysics Data System (ADS)

    Rice, Emily L.; Oppenheimer, B. R.; Zimmerman, N.; Roberts, L. C., Jr.; Hinkley, S.

    2012-01-01

    In the next few years, several high contrast imaging instruments equipped with integral field spectrographs will allow the direct spectral characterization of a variety of companions, from low-mass stars to Jupiter-mass extra-solar planets, at Solar System-like separations (4-40 AU). The spectra obtained by these instruments will be low resolution (R 30-60), making detailed thermo-chemical analysis difficult. Therefore, we have developed a technique that quantitatively compares observed low-resolution spectra with a set of synthetic spectra in order to obtain physical parameters, such as temperature and surface gravity, quickly and robustly. The technique requires no assumptions about age, mass, radius or metallicity of the companion or the primary. We describe this technique and demonstrate its effectiveness with simulated and observed spectra from Project 1640, the high contrast imager and integral field spectrograph on Palomar. The technique can also be used to optimize observing efficiency by determining the ideal wavelength range (for multi-filter instruments such as the Gemini Planet Imager) and signal to noise ratio for a desired precision and accuracy of inferred parameters. The current analysis uses the PHOENIX models as a basis for comparison, but the technique can be applied to any set of models and even used to quantify the differences between models created by different groups. This tool provides a necessary, fast, and comprehensive method of characterizing faint companions of stars, whether they be stellar, sub-stellar or planetary in nature.

  8. The BrainMap strategy for standardization, sharing, and meta-analysis of neuroimaging data

    PubMed Central

    2011-01-01

    Background Neuroimaging researchers have developed rigorous community data and metadata standards that encourage meta-analysis as a method for establishing robust and meaningful convergence of knowledge of human brain structure and function. Capitalizing on these standards, the BrainMap project offers databases, software applications, and other associated tools for supporting and promoting quantitative coordinate-based meta-analysis of the structural and functional neuroimaging literature. Findings In this report, we describe recent technical updates to the project and provide an educational description for performing meta-analyses in the BrainMap environment. Conclusions The BrainMap project will continue to evolve in response to the meta-analytic needs of biomedical researchers in the structural and functional neuroimaging communities. Future work on the BrainMap project regarding software and hardware advances are also discussed. PMID:21906305

  9. Super-resolution biomolecular crystallography with low-resolution data.

    PubMed

    Schröder, Gunnar F; Levitt, Michael; Brunger, Axel T

    2010-04-22

    X-ray diffraction plays a pivotal role in the understanding of biological systems by revealing atomic structures of proteins, nucleic acids and their complexes, with much recent interest in very large assemblies like the ribosome. As crystals of such large assemblies often diffract weakly (resolution worse than 4 A), we need methods that work at such low resolution. In macromolecular assemblies, some of the components may be known at high resolution, whereas others are unknown: current refinement methods fail as they require a high-resolution starting structure for the entire complex. Determining the structure of such complexes, which are often of key biological importance, should be possible in principle as the number of independent diffraction intensities at a resolution better than 5 A generally exceeds the number of degrees of freedom. Here we introduce a method that adds specific information from known homologous structures but allows global and local deformations of these homology models. Our approach uses the observation that local protein structure tends to be conserved as sequence and function evolve. Cross-validation with R(free) (the free R-factor) determines the optimum deformation and influence of the homology model. For test cases at 3.5-5 A resolution with known structures at high resolution, our method gives significant improvements over conventional refinement in the model as monitored by coordinate accuracy, the definition of secondary structure and the quality of electron density maps. For re-refinements of a representative set of 19 low-resolution crystal structures from the Protein Data Bank, we find similar improvements. Thus, a structure derived from low-resolution diffraction data can have quality similar to a high-resolution structure. Our method is applicable to the study of weakly diffracting crystals using X-ray micro-diffraction as well as data from new X-ray light sources. Use of homology information is not restricted to X-ray crystallography and cryo-electron microscopy: as optical imaging advances to subnanometre resolution, it can use similar tools. PMID:20376006

  10. Low-resolution refinement tools in REFMAC5

    PubMed Central

    Nicholls, Robert A.; Long, Fei; Murshudov, Garib N.

    2012-01-01

    Two aspects of low-resolution macromolecular crystal structure analysis are considered: (i) the use of reference structures and structural units for provision of structural prior information and (ii) map sharpening in the presence of noise and the effects of Fourier series termination. The generation of interatomic distance restraints by ProSMART and their subsequent application in REFMAC5 is described. It is shown that the use of such external structural information can enhance the reliability of derived atomic models and stabilize refinement. The problem of map sharpening is considered as an inverse deblurring problem and is solved using Tikhonov regularizers. It is demonstrated that this type of map sharpening can automatically produce a map with more structural features whilst maintaining connectivity. Tests show that both of these directions are promising, although more work needs to be performed in order to further exploit structural information and to address the problem of reliable electron-density calculation. PMID:22505260

  11. Performance and sensitivity of low-resolution spectrographs for LAMOST

    NASA Astrophysics Data System (ADS)

    Hou, Yonghui; Zhu, Yongtian; Hu, Zhongwen; Wang, Lei; Wang, Jianing

    2010-07-01

    The 16 low resolution spectrographs (LRS) have been successfully commissioned for the LAMOST. The LRS design employs a dual-beamed and bench-mounted, with large-beamed, fast Schmidt cameras and Volume Phase Holographic (VPH) transmission gratings. The design wavelength range is 370-900nm, at resolutions of R=1000and R=10000. Each spectrograph is fed by 250 fibers with 320 micron in diameter (corresponding 3.3 arcsec), composed of one F/4 Schmidt collimator, a dichroic beam-splitter, four VPH gratings, articulating Schmidt cameras that are optimized at blue band (370-590 nm) and red band (570-900 nm), and field lens near the focal plane service as the vacuum window of CCD detector cryogenic head. In this paper, we present the testing result of the LRS on the image quality, spectra resolution, efficiency and observing spectra.

  12. CARMENES science preparation: low--resolution spectroscopy of M dwarfs

    NASA Astrophysics Data System (ADS)

    Alonso-Floriano, F. J.; Montes, D.; Caballero, J. A.; Klutsch, A.; Mundt, R.; Córtes-Contreras, M.; Morales, J. C.; Quirrenbach, A.; Amado, P. J.; Reiners, A.; Ribas, I.

    2015-05-01

    CARMENES is the new optical/near-infrared spectrograph at Calar Alto observatory. The identification of the most promising targets for exoplanet hunting is a crucial first step to ensure an efficient use of the CARMENES guaranteed time. To achieve this, we obtained low-resolution (R ˜ 1500) spectra of 752 M (and late K) dwarfs, mostly fainter than J = 9 mag, using the CAFOS spectrograph of the 2.2 m telescope at Calar Alto observatory. We derived spectral types with 0.5 subtypes accuracy combining the spectral indices technique and the best-fit & χ^2 matches. We also studied metallicity and surface gravity through spectral indices, and activity from the pseudo-equivalent width of the Hα line. We identified high-activity, low-metallicity and low-gravity stars, which should be discarded for exoplanet searches. Here we present preliminary results.

  13. Estimation of low-resolution visible spectra from RGB imagery

    NASA Astrophysics Data System (ADS)

    Schau, H. C.

    2009-05-01

    While able to measure the red, green, and blue channels, color imagers are not true spectral imagers capable of spectral measurements. In this paper we present a processing technique for estimating low resolution visible spectra from (RGB) imagery components. Such a methodology will find application in separating reflectivity components from source illumination as performed in Retinex or Linear Models. Numerical processing is discussed and formulated within non-regulated iterative restoration methodology. Numerical stability and convergence are considered relative to speed and accuracy as well as calibration data effects on overall results. Implementation is demonstrated together with several suggestions for real time processing. Imager calibration methodology is presented together with several results. Limitations of the method are discussed as well as directions for further investigations.

  14. Low Resolution Picture Transmission (LRPT) Demonstration System. Phase II; 1.0

    NASA Technical Reports Server (NTRS)

    Fong, Wai; Yeh, Pen-Shu; Duran, Steve; Sank, Victor; Nyugen, Xuan; Xia, Wei; Day, John H. (Technical Monitor)

    2002-01-01

    Low-Resolution Picture Transmission (LRPT) is a proposed standard for direct broadcast transmission of satellite weather images. This standard is a joint effort by the European Organization for the Exploitation of Meteorological Satellites (EUMETSAT) and NOAA. As a digital transmission scheme, its purpose is to replace the current analog Automatic Picture Transmission (APT) system for use in the Meteorological Operational (METOP) satellites. GSFC has been tasked to build an LRPT Demonstration System (LDS). Its main objective is to develop or demonstrate the feasibility of a low-cost receiver utilizing a PC as the primary processing component and determine the performance of the protocol in the simulated Radio Frequency (RF) environment. The approach would consist of two phases.

  15. Quantification of trabecular spatial orientation from low-resolution images.

    PubMed

    Lenaerts, L; Wirth, A J; van Lenthe, G H

    2015-01-01

    No accepted methodology exists to assess trabecular bone orientation from clinical CT scans. The aim of this study was to test the hypothesis that the distribution of grey values in clinical CT images is related to the underlying trabecular architecture and that this distribution can be used to identify the principal directions and local anisotropy of trabecular bone. Fourteen trabecular bone samples were extracted from high-resolution (30 ?m) micro-CT scans of seven human femoral heads. Trabecular orientations and local anisotropy were calculated using grey-level deviation (GLD), a novel method providing a measure of the three-dimensional distribution of image grey values. This was repeated for different image resolutions down to 300 ?m and for volumes of interest (VOIs) ranging from 1 to 7 mm. Outcomes were compared with the principal mechanical directions and with mean intercept length (MIL) as calculated for the segmented 30-?m images. For the 30-?m images, GLD predicted the mechanical principal directions equally well as MIL. For the 300-?m images, which are resolutions that can be obtained in vivo using clinical CT, only a small increase (3°-6°) in the deviation from the mechanical orientations was found. VOIs of 5 mm resulted in a robust quantification of the orientation. We conclude that GLD can quantify structural bone parameters from low-resolution CT images. PMID:24787095

  16. Cartography of asteroids and comet nuclei from low resolution data

    NASA Technical Reports Server (NTRS)

    Stooke, Philip J.

    1992-01-01

    High resolution images of non-spherical objects, such as Viking images of Phobos and the anticipated Galileo images of Gaspra, lend themselves to conventional planetary cartographic procedures: control network analysis, stereophotogrammetry, image mosaicking in 2D or 3D, and airbrush mapping. There remains the problem of a suitable map projection for bodies which are extremely elongated or irregular in shape. Many bodies will soon be seen at lower resolution (5-30 pixels across the disk) in images from speckle interferometry, the Hubble Space Telescope, ground-based radar, distinct spacecraft encounters, and closer images degraded by smear. Different data with similar effective resolutions are available from stellar occultations, radar or lightcurve convex hulls, lightcurve modeling of albedo variations, and cometary jet modeling. With such low resolution, conventional methods of shape determination will be less useful or will fail altogether, leaving limb and terminator topography as the principal sources of topographic information. A method for shape determination based on limb and terminator topography was developed. It has been applied to the nucleus of Comet Halley and the jovian satellite Amalthea. The Amalthea results are described to give an example of the cartographic possibilities and problems of anticipated data sets.

  17. THE COSMIC INFRARED BACKGROUND EXPERIMENT (CIBER): THE LOW RESOLUTION SPECTROMETER

    SciTech Connect

    Tsumura, K.; Arai, T.; Matsumoto, T.; Matsuura, S.; Murata, K.; Battle, J.; Bock, J.; Brown, S.; Lykke, K.; Smith, A.; Cooray, A.; Hristov, V.; Levenson, L. R.; Mason, P.; Keating, B.; Renbarger, T.; Kim, M. G.; Lee, D. H.; Nam, U. W.; Sullivan, I.; and others

    2013-08-15

    Absolute spectrophotometric measurements of diffuse radiation at 1 {mu}m to 2 {mu}m are crucial to our understanding of the radiative content of the universe from nucleosynthesis since the epoch of reionization, the composition and structure of the zodiacal dust cloud in our solar system, and the diffuse galactic light arising from starlight scattered by interstellar dust. The Low Resolution Spectrometer (LRS) on the rocket-borne Cosmic Infrared Background Experiment is a {lambda}/{Delta}{lambda} {approx} 15-30 absolute spectrophotometer designed to make precision measurements of the absolute near-infrared sky brightness between 0.75 {mu}m <{lambda} < 2.1 {mu}m. This paper presents the optical, mechanical, and electronic design of the LRS, as well as the ground testing, characterization, and calibration measurements undertaken before flight to verify its performance. The LRS is shown to work to specifications, achieving the necessary optical and sensitivity performance. We describe our understanding and control of sources of systematic error for absolute photometry of the near-infrared extragalactic background light.

  18. Coupled kernel embedding for low resolution face image recognition.

    PubMed

    Ren, Chuan-Xian; Dai, Dao-Qing; Yan, Hong

    2012-08-01

    Practical video scene and face recognition systems are sometimes confronted with low-resolution (LR) images. The faces may be very small even if the video is clear, thus it is difficult to directly measure the similarity between the faces and the high-resolution (HR) training samples. Traditional super-resolution (SR) methods based face recognition usually have limited performance because the target of SR may not be consistent with that of classification, and time-consuming SR algorithms are not suitable for real-time applications. In this paper, a new feature extraction method called Coupled Kernel Embedding (CKE) is proposed for LR face recognition without any SR preprocessing. In this method, the final kernel matrix is constructed by concatenating two individual kernel matrices in the diagonal direction, and the (semi-)positively definite properties are preserved for optimization. CKE addresses the problem of comparing multi-modal data that are difficult for conventional methods in practice due to the lack of an efficient similarity measure. Particularly, different kernel types (e.g., linear, Gaussian, polynomial) can be integrated into an uniformed optimization objective, which cannot be achieved by simple linear methods. CKE solves this problem by minimizing the dissimilarities captured by their kernel Gram matrices in the low- and high-resolution spaces. In the implementation, the nonlinear objective function is minimized by a generalized eigenvalue decomposition. Experiments on benchmark and real databases show that our CKE method indeed improves the recognition performance. PMID:22481822

  19. Is there texture information in standard brain MRI?

    NASA Astrophysics Data System (ADS)

    Soltanian-Zadeh, Hamid; Nezafat, Reza; Windham, Joe P.

    1999-05-01

    We have developed a texture feature extraction method for MRI utilizing the recently developed multiwavelet theory. Texture based features are used in Eigenimage Filtering to enhance analysis results of tumor patient MRI studies. The steps of the proposed method are as follows: (1) Each original image is convolved with a Gaussian filter. This step suppresses the image noise. (2) Each of the resulting images is convolved with eight multiwavelet coefficient matrices. (3) The output of each filter is stored in a separate image (feature plane). This step generates features (images) in which texture information is enhanced. (4) Local energy of each feature is calculated by squaring the feature values. This step converts variance disparities into mean value differences and transforms large values of local pass- band energy into large image gray levels. (5) Eigenimage filter is applied to different sets of MRI images and the results are compared. First, it is applied to the conventional MRI images (T1-weighted, T2-weighted, and proton density weighted). Then, it is applied to the set consisting of these images and the texture feature images generated in the previous step for them. Finally, it is applied to four original images (three conventional and a non-conventional). (6) The eigenimages obtained in the previous step are compared. This step illustrates presence and significance of the texture information present in MRI and role of the proposed method in extracting these features. Applications of the proposed method to MRI studies of brain tumor patients illustrate that the method successfully extracts texture features which are useful in tumor segmentation and characterization.

  20. Investigating short wavelength correlated errors on low resolution mode altimetry

    NASA Astrophysics Data System (ADS)

    Poisson, Jean-Christophe; Thibaut, Pierre; Dibarboure, Gérald; Labroue, Sylvie; Lasne, Yannick; Boy, François; Picot, Nicolas

    2013-04-01

    Although conventional radar altimetry products (Jason1, Jason2, LRM CRYOSAT2, etc) have a spatial resolution as high as 300 m, the observation of ocean scales smaller than 100 km is limited by the existence of a "spectral hump", i.e. a geographically coherent error. In the frame of the future altimetry missions (SAR for Cryosat -2 and Sentinel-3 missions and interferometry for the SWOT mission) it becomes crucial to investigate again and to better understand the signals obtained at small scales by conventional altimeter missions. Through an analysis of simulations, we show that heterogeneous backscattering scenes can result in the corruption of the altimeter waveforms and retracked parameters. The retrackers used in current ground processors cannot well fit the Brown model during backscattering events because this model has been designed for a homogeneous scene. The error is also propagated along-track because of the size and shape of the low resolution mode (LRM) disc-shaped footprint. The hump phenomenon is shown to be almost ubiquitous in the ocean, yet more intense at low latitudes and in the Indian Ocean and Western Pacific Ocean, where backscattering events are more frequent. Its overall signature could be a Gaussian-like random signal smooth for wavelengths smaller than 15 km, i.e. white noise on 1 Hz products. The analysis of current data from 5 altimetry missions highlights the influence of the instrument design and altitude, and the influence of the retracker used. The spectral hump is a systematic response to random events and it is possible to mitigate it with new processing. Simulations and geographically limited datasets from the synthetic aperture radar mode (SARM) of Cryosat-2 show that the thin stripe-shaped synthetic footprint of SARM might be less sensitive to the artifact.

  1. Brain Oscillatory Activity during Spatial Navigation: Theta and Gamma Activity Link Medial Temporal and Parietal Regions

    ERIC Educational Resources Information Center

    White, David J.; Congedo, Marco; Ciorciari, Joseph; Silberstein, Richard B.

    2012-01-01

    Brain oscillatory correlates of spatial navigation were investigated using blind source separation (BSS) and standardized low resolution electromagnetic tomography (sLORETA) analyses of 62-channel EEG recordings. Twenty-five participants were instructed to navigate to distinct landmark buildings in a previously learned virtual reality town…

  2. Brain Oscillatory Activity during Spatial Navigation: Theta and Gamma Activity Link Medial Temporal and Parietal Regions

    ERIC Educational Resources Information Center

    White, David J.; Congedo, Marco; Ciorciari, Joseph; Silberstein, Richard B.

    2012-01-01

    Brain oscillatory correlates of spatial navigation were investigated using blind source separation (BSS) and standardized low resolution electromagnetic tomography (sLORETA) analyses of 62-channel EEG recordings. Twenty-five participants were instructed to navigate to distinct landmark buildings in a previously learned virtual reality town…

  3. Zebrafish brain mapping--standardized spaces, length scales, and the power of N and n.

    PubMed

    Hunter, Paul R; Hendry, Aenea C; Lowe, Andrew S

    2015-06-01

    Mapping anatomical and functional parameters of the zebrafish brain is moving apace. Research communities undertaking such studies are becoming ever larger and more diverse. The unique features, tools, and technologies associated with zebrafish are propelling them as the 21st century model organism for brain mapping. Uniquely positioned as a vertebrate model system, the zebrafish enables imaging of anatomy and function at different length scales from intraneuronal compartments to sparsely distributed whole brain patterns. With a variety of diverse and established statistical modeling and analytic methods available from the wider brain mapping communities, the richness of zebrafish neuroimaging data is being realized. The statistical power of population observations (N) within and across many samples (n) projected onto a standardized space will provide vast databases for data-driven biological approaches. This article reviews key brain mapping initiatives at different levels of scale that highlight the potential of zebrafish brain mapping. By way of introduction to the next wave of brain mappers, an accessible introduction to the key concepts and caveats associated with neuroimaging are outlined and discussed. PMID:25418847

  4. Anatomic standardization: Linear scaling and nonlinear warping of functional brain images

    SciTech Connect

    Minoshima, S.; Koeppe, R.A.; Frey, K.A.

    1994-09-01

    An automated method was proposed for anatomic standardization of PET scans in three dimensions, which enabled objective intersubject and cross-group comparisons of functional brain images. The method involved linear scaling to correct for individual brain size and nonlinear warping to minimize regional anatomic variations among subjects. In the linear-scaling step, the anteroposterior length and width of the brain were measured on the PET images, and the brain height was estimated by a contour-matching procedure using the midsagittal plane. In the nonlinear warping step, individual gray matter locations were matched with those of a standard brain by maximizing correlation coefficients of regional profile curves determined between predefined stretching centers (predominantly in white matter) and the gray matter landmarks. The accuracy of the brain height estimation was compared with skull x-ray estimations, showing comparable accuracy and better reproducibility. Linear-scaling and nonlinear warping methods were validated using ({sup 18}F)fluorodeoxyglucose and ({sup 15}O)water images. Regional anatomic variability on the glucose images was reduced markedly. The statistical significance of activation foci in paired water images was improved in both vibratory and visual activation paradigms. A group versus group comparison following the proposed anatomic standardization revealed highly significant glucose metabolic alterations in the brains of patients with Alzheimer`s disease compared with those of a normal control group. These results suggested that the method is well suited to both research and clinical settings and can facilitate pixel-by-pixel comparisons of PET images. 26 refs., 9 figs., 1 tab.

  5. 10 Best Teaching Practices: How Brain Research, Learning Styles, and Standards Define Teaching Competencies.

    ERIC Educational Resources Information Center

    Tileston, Donna Walker

    This book presents 10 practices that are essential to making education meaningful and rich for all students, examining brain research and how it can be applied to the classroom. It incorporates information about learning styles and standards into a classroom instructional model for teachers. The 11 chapters are as follows: (1) "Creating an…

  6. A grid-enabled web service for low-resolution crystal structure refinement

    PubMed Central

    O’Donovan, Daniel J.; Stokes-Rees, Ian; Nam, Yunsun; Blacklow, Stephen C.; Schröder, Gunnar F.; Brunger, Axel T.; Sliz, Piotr

    2012-01-01

    Deformable elastic network (DEN) restraints have proved to be a powerful tool for refining structures from low-resolution X-ray crystallographic data sets. Unfortunately, optimal refinement using DEN restraints requires extensive calculations and is often hindered by a lack of access to sufficient computational resources. The DEN web service presented here intends to provide structural biologists with access to resources for running computationally intensive DEN refinements in parallel on the Open Science Grid, the US cyberinfrastructure. Access to the grid is provided through a simple and intuitive web interface integrated into the SBGrid Science Portal. Using this portal, refinements combined with full parameter optimization that would take many thousands of hours on standard computational resources can now be completed in several hours. An example of the successful application of DEN restraints to the human Notch1 transcriptional complex using the grid resource, and summaries of all submitted refinements, are presented as justification. PMID:22349228

  7. A human post-mortem brain model for the standardization of multi-centre MRI studies.

    PubMed

    Droby, Amgad; Lukas, Carsten; Schänzer, Anne; Spiwoks-Becker, Isabella; Giorgio, Antonio; Gold, Ralf; De Stefano, Nicola; Kugel, Harald; Deppe, Michael; Wiendl, Heinz; Meuth, Sven G; Acker, Till; Zipp, Frauke; Deichmann, Ralf

    2015-04-15

    Multi-centre MRI studies of the brain are essential for enrolling large and diverse patient cohorts, as required for the investigation of heterogeneous neurological and psychiatric diseases. However, the multi-site comparison of standard MRI data sets that are weighted with respect to tissue parameters such as the relaxation times (T1, T2) and proton density (PD) may be problematic, as signal intensities and image contrasts depend on site-specific details such as the sequences used, imaging parameters, and sensitivity profiles of the radiofrequency (RF) coils. Water or gel phantoms are frequently used for long-term and/or inter-site quality assessment. However, these phantoms hardly mimic the structure, shape, size or tissue distribution of the human brain. The goals of this study were: (1) to validate the long-term stability of a human post-mortem brain phantom, performing quantitative mapping of T1, T2, and PD, and the magnetization transfer ratio (MTR) over a period of 18months; (2) to acquire and analyse data for this phantom and the brain of a healthy control (HC) in a multi-centre study for MRI protocol standardization in four centres, while conducting a voxel-wise as well as whole brain grey (GM) and white matter (WM) tissue volume comparison. MTR, T2, and the quotient of PD in WM and GM were stable in the post-mortem brain with no significant changes. T1 was found to decrease from 267/236ms (GM/WM) to 234/216ms between 5 and 17weeks post embedment, stabilizing during an 18-month period following the first scan at about 215/190ms. The volumetric measures, based on T1-weighted MP-RAGE images obtained at all participating centres, revealed inter- and intra-centre variations in the evaluated GM and WM volumes that displayed similar trends in both the post-mortem brain as well as the HC. At a confidence level of 95%, brain regions such as the brainstem, deep GM structures as well as boundaries between GM and WM tissues were found to be less reproducible than other brain regions in all participating centres. The results demonstrate that a post-mortem brain phantom may be used as a reliable tool for multi-centre MR studies. PMID:25595502

  8. Development of image and information management system for Korean standard brain

    NASA Astrophysics Data System (ADS)

    Chung, Soon Cheol; Choi, Do Young; Tack, Gye Rae; Sohn, Jin Hun

    2004-04-01

    The purpose of this study is to establish a reference for image acquisition for completing a standard brain for diverse Korean population, and to develop database management system that saves and manages acquired brain images and personal information of subjects. 3D MP-RAGE (Magnetization Prepared Rapid Gradient Echo) technique which has excellent Signal to Noise Ratio (SNR) and Contrast to Noise Ratio (CNR) as well as reduces image acquisition time was selected for anatomical image acquisition, and parameter values were obtained for the optimal image acquisition. Using these standards, image data of 121 young adults (early twenties) were obtained and stored in the system. System was designed to obtain, save, and manage not only anatomical image data but also subjects' basic demographic factors, medical history, handedness inventory, state-trait anxiety inventory, A-type personality inventory, self-assessment depression inventory, mini-mental state examination, intelligence test, and results of personality test via a survey questionnaire. Additionally this system was designed to have functions of saving, inserting, deleting, searching, and printing image data and personal information of subjects, and to have accessibility to them as well as automatic connection setup with ODBC. This newly developed system may have major contribution to the completion of a standard brain for diverse Korean population since it can save and manage their image data and personal information.

  9. Brain

    MedlinePLUS

    ... will return after updating. Resources Archived Modules Updates Brain Cerebrum The cerebrum is the part of the ... the outside of the brain and spinal cord. Brain Stem The brain stem is the part of ...

  10. INTERPRETATION OF LOW RESOLUTION MASS SPECTRA FOR LEVEL 1 ANALYSIS OF ENVIRONMENTAL MIXTURES

    EPA Science Inventory

    The report gives guidelines for interpreting the low resolution mass spectra (LRMS) of complex chemical mixtures, within the context of the EPA Level 1 Environmental Assessment Program. It discusses the principles underlying direct mass spectrometric analysis of complex mixtures,...

  11. Low-Resolution Spectroscopy of Primitive Asteroids: Progress Report for SARA/VSU Survey

    NASA Technical Reports Server (NTRS)

    Leake, M. A.; Nogues, J. P.; Gaines, J. K.; Looper, J. K.; Freitas, K. A.

    2001-01-01

    Progress on a low-resolution survey of primitive C-class asteroids continues using new equipment (and its associated problems) to understand aqueous alteration in the solar system. Additional information is contained in the original extended abstract.

  12. CARMENES input catalogue of M dwarfs. I. Low-resolution spectroscopy with CAFOS

    NASA Astrophysics Data System (ADS)

    Alonso-Floriano, F. J.; Morales, J. C.; Caballero, J. A.; Montes, D.; Klutsch, A.; Mundt, R.; Cortés-Contreras, M.; Ribas, I.; Reiners, A.; Amado, P. J.; Quirrenbach, A.; Jeffers, S. V.

    2015-05-01

    Context. CARMENES is a stabilised, high-resolution, double-channel spectrograph at the 3.5 m Calar Alto telescope. It is optimally designed for radial-velocity surveys of M dwarfs with potentially habitable Earth-mass planets. Aims: We prepare a list of the brightest, single M dwarfs in each spectral subtype observable from the northern hemisphere, from which we will select the best planet-hunting targets for CARMENES. Methods: In this first paper on the preparation of our input catalogue, we compiled a large amount of public data and collected low-resolution optical spectroscopy with CAFOS at the 2.2 m Calar Alto telescope for 753 stars. We derived accurate spectral types using a dense grid of standard stars, a double least-squares minimisation technique, and 31 spectral indices previously defined by other authors. Additionally, we quantified surface gravity, metallicity, and chromospheric activity for all the stars in our sample. Results: We calculated spectral types for all 753 stars, of which 305 are new and 448 are revised. We measured pseudo-equivalent widths of Hα for all the stars in our sample, concluded that chromospheric activity does not affect spectral typing from our indices, and tabulated 49 stars that had been reported to be young stars in open clusters, moving groups, and stellar associations. Of the 753 stars, two are new subdwarf candidates, three are T Tauri stars, 25 are giants, 44 are K dwarfs, and 679 are M dwarfs. Many of the 261 investigated dwarfs in the range M4.0-8.0 V are among the brightest stars known in their spectral subtype. Conclusions: This collection of low-resolution spectroscopic data serves as a candidate target list for the CARMENES survey and can be highly valuable for other radial-velocity surveys of M dwarfs and for studies of cool dwarfs in the solar neighbourhood. Full Tables A.1, A.2, and A.3 are only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (ftp://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/577/A128

  13. Discrimination and tracking of dismounts using low-resolution aerial video sequences

    NASA Astrophysics Data System (ADS)

    Narayanaswami, Ranga; Tyurina, Anastasia; Diel, David; Mehra, Raman K.; Chinn, Janice M.

    2011-09-01

    In this paper, we address the problem of robust detection of dismounts from low-resolution video data sequences. We outline a methodology based on SSCI's ultra-fast image alignment algorithm, and a combination of static and kinematic features for dismount detection. We perform the dismount detection classification using a learning classifier algorithm. Our results are promising and very valuable for low-resolution imagery where previous techniques for dismount detection such as SURF and SIFT features do not perform very well.

  14. Improved EEG source analysis using low resolution conductivity estimation in a four-compartment finite element head model

    PubMed Central

    Lew, S.; Wolters, C. H.; Anwander, A.; Makeig, S.; MacLeod, R.

    2009-01-01

    Bioelectric source analysis in the human brain from scalp electroencephalography (EEG) signals is sensitive to geometry and conductivity properties of the different head tissues. We propose a low resolution conductivity estimation (LRCE) method using simulated annealing optimization on high resolution finite element models that individually optimizes a realistically-shaped four-layer volume conductor with regard to the brain and skull compartment conductivities. As input data, the method needs T1- and PD-weighted magnetic resonance images for an improved modeling of the skull and the cerebrospinal fluid compartment and evoked potential data with high signal-to-noise ratio (SNR). Our simulation studies showed that for EEG data with realistic SNR, the LRCE method was able to simultaneously reconstruct both the brain and the skull conductivity together with the underlying dipole source and provided an improved source analysis result. We have also demonstrated the feasibility and applicability of the new method to simultaneously estimate brain and skull conductivity and a somatosensory source from measured tactile somatosensory evoked potentials of a human subject. Our results show the viability of an approach that computes its own conductivity values and thus reduces the dependence on assigning values from the literature and likely produces a more robust estimate of current sources. Using the LRCE method, the individually optimized four-compartment volume conductor model can in a second step be used for the analysis of clinical or cognitive data acquired from the same subject. PMID:19117275

  15. 3D Standard Brain of the Red Flour Beetle Tribolium Castaneum: A Tool to Study Metamorphic Development and Adult Plasticity

    PubMed Central

    Dreyer, David; Vitt, Holger; Dippel, Stefan; Goetz, Brigitte; el Jundi, Basil; Kollmann, Martin; Huetteroth, Wolf; Schachtner, Joachim

    2009-01-01

    The red flour beetle Tribolium castaneum is emerging as a further standard insect model beside Drosophila. Its genome is fully sequenced and it is susceptible for genetic manipulations including RNA-interference. We use this beetle to study adult brain development and plasticity primarily with respect to the olfactory system. In the current study, we provide 3D standard brain atlases of freshly eclosed adult female and male beetles (A0). The atlases include eight paired and three unpaired neuropils including antennal lobes (ALs), optic lobe neuropils, mushroom body calyces and pedunculi, and central complex. For each of the two standard brains, we averaged brain areas of 20 individual brains. Additionally, we characterized eight selected olfactory glomeruli from 10 A0 female and male beetles respectively, which we could unequivocally recognize from individual to individual owing to their size and typical position in the ALs. In summary, comparison of the averaged neuropil volumes revealed no sexual dimorphism in any of the reconstructed neuropils in A0 Tribolium brains. Both, the female and male 3D standard brain are also used for interspecies comparisons, and, importantly, will serve as future volumetric references after genetical manipulation especially regarding metamorphic development and adult plasticity. PMID:20339482

  16. The standard-based open workflow system in GeoBrain (Invited)

    NASA Astrophysics Data System (ADS)

    Di, L.; Yu, G.; Zhao, P.; Deng, M.

    2013-12-01

    GeoBrain is an Earth science Web-service system developed and operated by the Center for Spatial Information Science and Systems, George Mason University. In GeoBrain, a standard-based open workflow system has been implemented to accommodate the automated processing of geospatial data through a set of complex geo-processing functions for advanced production generation. The GeoBrain models the complex geoprocessing at two levels, the conceptual and concrete. At the conceptual level, the workflows exist in the form of data and service types defined by ontologies. The workflows at conceptual level are called geo-processing models and cataloged in GeoBrain as virtual product types. A conceptual workflow is instantiated into a concrete, executable workflow when a user requests a product that matches a virtual product type. Both conceptual and concrete workflows are encoded in Business Process Execution Language (BPEL). A BPEL workflow engine, called BPELPower, has been implemented to execute the workflow for the product generation. A provenance capturing service has been implemented to generate the ISO 19115-compliant complete product provenance metadata before and after the workflow execution. The generation of provenance metadata before the workflow execution allows users to examine the usability of the final product before the lengthy and expensive execution takes place. The three modes of workflow executions defined in the ISO 19119, transparent, translucent, and opaque, are available in GeoBrain. A geoprocessing modeling portal has been developed to allow domain experts to develop geoprocessing models at the type level with the support of both data and service/processing ontologies. The geoprocessing models capture the knowledge of the domain experts and are become the operational offering of the products after a proper peer review of models is conducted. An automated workflow composition has been experimented successfully based on ontologies and artificial intelligence technology. The GeoBrain workflow system has been used in multiple Earth science applications, including the monitoring of global agricultural drought, the assessment of flood damage, the derivation of national crop condition and progress information, and the detection of nuclear proliferation facilities and events.

  17. Functional connectivity classification of autism identifies highly predictive brain features but falls short of biomarker standards

    PubMed Central

    Plitt, Mark; Barnes, Kelly Anne; Martin, Alex

    2014-01-01

    Objectives Autism spectrum disorders (ASD) are diagnosed based on early-manifesting clinical symptoms, including markedly impaired social communication. We assessed the viability of resting-state functional MRI (rs-fMRI) connectivity measures as diagnostic biomarkers for ASD and investigated which connectivity features are predictive of a diagnosis. Methods Rs-fMRI scans from 59 high functioning males with ASD and 59 age- and IQ-matched typically developing (TD) males were used to build a series of machine learning classifiers. Classification features were obtained using 3 sets of brain regions. Another set of classifiers was built from participants' scores on behavioral metrics. An additional age and IQ-matched cohort of 178 individuals (89 ASD; 89 TD) from the Autism Brain Imaging Data Exchange (ABIDE) open-access dataset (http://fcon_1000.projects.nitrc.org/indi/abide/) were included for replication. Results High classification accuracy was achieved through several rs-fMRI methods (peak accuracy 76.67%). However, classification via behavioral measures consistently surpassed rs-fMRI classifiers (peak accuracy 95.19%). The class probability estimates, P(ASD|fMRI data), from brain-based classifiers significantly correlated with scores on a measure of social functioning, the Social Responsiveness Scale (SRS), as did the most informative features from 2 of the 3 sets of brain-based features. The most informative connections predominantly originated from regions strongly associated with social functioning. Conclusions While individuals can be classified as having ASD with statistically significant accuracy from their rs-fMRI scans alone, this method falls short of biomarker standards. Classification methods provided further evidence that ASD functional connectivity is characterized by dysfunction of large-scale functional networks, particularly those involved in social information processing. PMID:25685703

  18. xMDFF: molecular dynamics flexible fitting of low-resolution X-ray structures

    SciTech Connect

    McGreevy, Ryan; Singharoy, Abhishek; Li, Qufei; Zhang, Jingfen; Xu, Dong; Perozo, Eduardo; Schulten, Klaus

    2014-09-01

    A new real-space refinement method for low-resolution X-ray crystallography is presented. The method is based on the molecular dynamics flexible fitting protocol targeted at addressing large-scale deformations of the search model to achieve refinement with minimal manual intervention. An explanation of the method is provided, augmented by results from the refinement of both synthetic and experimental low-resolution data, including an independent electrophysiological verification of the xMDFF-refined crystal structure of a voltage-sensor protein. X-ray crystallography remains the most dominant method for solving atomic structures. However, for relatively large systems, the availability of only medium-to-low-resolution diffraction data often limits the determination of all-atom details. A new molecular dynamics flexible fitting (MDFF)-based approach, xMDFF, for determining structures from such low-resolution crystallographic data is reported. xMDFF employs a real-space refinement scheme that flexibly fits atomic models into an iteratively updating electron-density map. It addresses significant large-scale deformations of the initial model to fit the low-resolution density, as tested with synthetic low-resolution maps of d-ribose-binding protein. xMDFF has been successfully applied to re-refine six low-resolution protein structures of varying sizes that had already been submitted to the Protein Data Bank. Finally, via systematic refinement of a series of data from 3.6 to 7 Å resolution, xMDFF refinements together with electrophysiology experiments were used to validate the first all-atom structure of the voltage-sensing protein Ci-VSP.

  19. xMDFF: molecular dynamics flexible fitting of low-resolution X-ray structures.

    PubMed

    McGreevy, Ryan; Singharoy, Abhishek; Li, Qufei; Zhang, Jingfen; Xu, Dong; Perozo, Eduardo; Schulten, Klaus

    2014-09-01

    X-ray crystallography remains the most dominant method for solving atomic structures. However, for relatively large systems, the availability of only medium-to-low-resolution diffraction data often limits the determination of all-atom details. A new molecular dynamics flexible fitting (MDFF)-based approach, xMDFF, for determining structures from such low-resolution crystallographic data is reported. xMDFF employs a real-space refinement scheme that flexibly fits atomic models into an iteratively updating electron-density map. It addresses significant large-scale deformations of the initial model to fit the low-resolution density, as tested with synthetic low-resolution maps of D-ribose-binding protein. xMDFF has been successfully applied to re-refine six low-resolution protein structures of varying sizes that had already been submitted to the Protein Data Bank. Finally, via systematic refinement of a series of data from 3.6 to 7?Å resolution, xMDFF refinements together with electrophysiology experiments were used to validate the first all-atom structure of the voltage-sensing protein Ci-VSP. PMID:25195748

  20. xMDFF: molecular dynamics flexible fitting of low-resolution X-ray structures

    PubMed Central

    McGreevy, Ryan; Singharoy, Abhishek; Li, Qufei; Zhang, Jingfen; Xu, Dong; Perozo, Eduardo; Schulten, Klaus

    2014-01-01

    X-ray crystallography remains the most dominant method for solving atomic structures. However, for relatively large systems, the availability of only medium-to-low-resolution diffraction data often limits the determination of all-atom details. A new molecular dynamics flexible fitting (MDFF)-based approach, xMDFF, for determining structures from such low-resolution crystallographic data is reported. xMDFF employs a real-space refinement scheme that flexibly fits atomic models into an iteratively updating electron-density map. It addresses significant large-scale deformations of the initial model to fit the low-resolution density, as tested with synthetic low-resolution maps of d-ribose-binding protein. xMDFF has been successfully applied to re-refine six low-resolution protein structures of varying sizes that had already been submitted to the Protein Data Bank. Finally, via systematic refinement of a series of data from 3.6 to 7?Å resolution, xMDFF refinements together with electro­physiology experiments were used to validate the first all-atom structure of the voltage-sensing protein Ci-VSP. PMID:25195748

  1. MEASURING ORGANIC MOLECULAR EMISSION IN DISKS WITH LOW-RESOLUTION SPITZER SPECTROSCOPY

    SciTech Connect

    Teske, Johanna K.; Najita, Joan R.; Carr, John S.; Pascucci, Ilaria; Apai, Daniel; Henning, Thomas E-mail: najita@noao.edu E-mail: pascucci@stsci.edu E-mail: henning@mpia.de

    2011-06-10

    We explore the extent to which Spitzer Infrared Spectrograph (IRS) spectra taken at low spectral resolution can be used in quantitative studies of organic molecular emission from disks surrounding low-mass young stars. We use Spitzer IRS spectra taken in both the high- and low-resolution modules for the same sources to investigate whether it is possible to define line indices that can measure trends in the strength of the molecular features in low-resolution data. We find that trends in the HCN emission strength seen in the high-resolution data can be recovered in low-resolution data. In examining the factors that influence the HCN emission strength, we find that the low-resolution HCN flux is modestly correlated with stellar accretion rate and X-ray luminosity. Correlations of this kind are perhaps expected based on recent observational and theoretical studies of inner disk atmospheres. Our results demonstrate the potential of using the large number of low-resolution disk spectra that reside in the Spitzer archive to study the factors that influence the strength of molecular emission from disks. Such studies would complement results for the much smaller number of circumstellar disks that have been observed at high resolution with IRS.

  2. Deformable complex network for refining low-resolution X-ray structures

    PubMed Central

    Zhang, Chong; Wang, Qinghua; Ma, Jianpeng

    2015-01-01

    In macromolecular X-ray crystallography, building more accurate atomic models based on lower resolution experimental diffraction data remains a great challenge. Previous studies have used a deformable elastic network (DEN) model to aid in low-resolution structural refinement. In this study, the development of a new refinement algorithm called the deformable complex network (DCN) is reported that combines a novel angular network-based restraint with the DEN model in the target function. Testing of DCN on a wide range of low-resolution structures demonstrated that it constantly leads to significantly improved structural models as judged by multiple refinement criteria, thus representing a new effective refinement tool for low-resolution structural determination. PMID:26527134

  3. Aircraft recognition in low-resolution SAR imagery using peak feature matching

    NASA Astrophysics Data System (ADS)

    Niu, Zhaodong; Pan, Jiameng; Lin, Chenglong; Chen, Zengping

    2015-12-01

    Aircraft recognition is of great theoretical and practical significance in fields like remote sensing, navigation and traffic monitoring. It seems difficult to recognize aircraft in low-resolution SAR imagery because of difference between real image and simulated template induced by poor image quality and inherent simulation error. Aiming at this problem, an aircraft recognition method using peak feature matching is proposed. Firstly, the scattering centers of detected target are extracted in low-resolution SAR imagery using an adaptive threshold. Secondly, the extracted peak features are used to estimate the aircraft azimuth angle, which can be used to reduce the searching space in template database dramatically. Finally, a novel peak feature matching method using spatial distribution information of entire peak set is proposed to measure the similarity between detected target and simulated template. Experimental results demonstrate the good performance of the proposed method on a variety of low-resolution SAR imageries.

  4. Standardizing ICU management of pediatric traumatic brain injury is associated with improved outcomes at discharge.

    PubMed

    O'Lynnger, Thomas M; Shannon, Chevis N; Le, Truc M; Greeno, Amber; Chung, Dai; Lamb, Fred S; Wellons, John C

    2016-01-01

    OBJECT The goal of critical care in treating traumatic brain injury (TBI) is to reduce secondary brain injury by limiting cerebral ischemia and optimizing cerebral blood flow. The authors compared short-term outcomes as defined by discharge disposition and Glasgow Outcome Scale scores in children with TBI before and after the implementation of a protocol that standardized decision-making and interventions among neurosurgeons and pediatric intensivists. METHODS The authors performed a retrospective pre- and postprotocol study of 128 pediatric patients with severe TBI, as defined by Glasgow Coma Scale (GCS) scores < 8, admitted to a tertiary care center pediatric critical care unit between April 1, 2008, and May 31, 2014. The preprotocol group included 99 patients, and the postprotocol group included 29 patients. The primary outcome of interest was discharge disposition before and after protocol implementation, which took place on April 1, 2013. Ordered logistic regression was used to assess outcomes while accounting for injury severity and clinical parameters. Favorable discharge disposition included discharge home. Unfavorable discharge disposition included discharge to an inpatient facility or death. RESULTS Demographics were similar between the treatment periods, as was injury severity as assessed by GCS score (mean 5.43 preprotocol, mean 5.28 postprotocol; p = 0.67). The ordered logistic regression model demonstrated an odds ratio of 4.0 of increasingly favorable outcome in the postprotocol cohort (p = 0.007). Prior to protocol implementation, 63 patients (64%) had unfavorable discharge disposition and 36 patients (36%) had favorable discharge disposition. After protocol implementation, 9 patients (31%) had unfavorable disposition, while 20 patients (69%) had favorable disposition (p = 0.002). In the preprotocol group, 31 patients (31%) died while 6 patients (21%) died after protocol implementation (p = 0.04). CONCLUSIONS Discharge disposition and mortality rates in pediatric patients with severe TBI improved after implementation of a standardized protocol among caregivers based on best-practice guidelines. PMID:26451717

  5. Quantitative analysis of the detergent-insoluble brain proteome in frontotemporal lobar degeneration using SILAC internal standards.

    PubMed

    Seyfried, Nicholas T; Gozal, Yair M; Donovan, Laura E; Herskowitz, Jeremy H; Dammer, Eric B; Xia, Qiangwei; Ku, Li; Chang, Jianjun; Duong, Duc M; Rees, Howard D; Cooper, Deborah S; Glass, Jonathan D; Gearing, Marla; Tansey, Malú G; Lah, James J; Feng, Yue; Levey, Allan I; Peng, Junmin

    2012-05-01

    A hallmark of neurodegeneration is the aggregation of disease related proteins that are resistant to detergent extraction. In the major pathological subtype of frontotemporal lobar degeneration (FTLD), modified TAR-DNA binding protein 43 (TDP-43), including phosphorylated, ubiquitinated, and proteolytically cleaved forms, is enriched in detergent-insoluble fractions from post-mortem brain tissue. Additional proteins that accumulate in the detergent-insoluble FTLD brain proteome remain largely unknown. In this study, we used proteins from stable isotope-labeled (SILAC) human embryonic kidney 293 cells (HEK293) as internal standards for peptide quantitation across control and FTLD insoluble brain proteomes. Proteins were identified and quantified by liquid-chromatography coupled with tandem mass spectrometry (LC-MS/MS) and 21 proteins were determined to be enriched in FTLD using SILAC internal standards. In parallel, label-free quantification of only the unlabeled brain derived peptides by spectral counts (SC) and G-test analysis identified additional brain-specific proteins significantly enriched in disease. Several proteins determined to be enriched in FTLD using SILAC internal standards were not considered significant by G-test due to their low total number of SC. However, immunoblotting of FTLD and control samples confirmed enrichment of these proteins, highlighting the utility of SILAC internal standard to quantify low-abundance proteins in brain. Of these, the RNA binding protein PTB-associated splicing factor (PSF) was further characterized because of structural and functional similarities to TDP-43. Full-length PSF and shorter molecular weight fragments, likely resulting from proteolytic cleavage, were enriched in FTLD cases. Immunohistochemical analysis of PSF revealed predominately nuclear localization in control and FTLD brain tissue and was not associated with phosphorylated pathologic TDP-43 neuronal inclusions. However, in a subset of FTLD cases, PSF was aberrantly localized to the cytoplasm of oligodendrocytes. These data raise the possibility that PSF directed RNA processes in oligodendrocytes are altered in neurodegenerative disease. PMID:22416763

  6. Consensus recommendations for a standardized Brain Tumor Imaging Protocol in clinical trials.

    PubMed

    Ellingson, Benjamin M; Bendszus, Martin; Boxerman, Jerrold; Barboriak, Daniel; Erickson, Bradley J; Smits, Marion; Nelson, Sarah J; Gerstner, Elizabeth; Alexander, Brian; Goldmacher, Gregory; Wick, Wolfgang; Vogelbaum, Michael; Weller, Michael; Galanis, Evanthia; Kalpathy-Cramer, Jayashree; Shankar, Lalitha; Jacobs, Paula; Pope, Whitney B; Yang, Dewen; Chung, Caroline; Knopp, Michael V; Cha, Soonme; van den Bent, Martin J; Chang, Susan; Yung, W K Al; Cloughesy, Timothy F; Wen, Patrick Y; Gilbert, Mark R

    2015-09-01

    A recent joint meeting was held on January 30, 2014, with the US Food and Drug Administration (FDA), National Cancer Institute (NCI), clinical scientists, imaging experts, pharmaceutical and biotech companies, clinical trials cooperative groups, and patient advocate groups to discuss imaging endpoints for clinical trials in glioblastoma. This workshop developed a set of priorities and action items including the creation of a standardized MRI protocol for multicenter studies. The current document outlines consensus recommendations for a standardized Brain Tumor Imaging Protocol (BTIP), along with the scientific and practical justifications for these recommendations, resulting from a series of discussions between various experts involved in aspects of neuro-oncology neuroimaging for clinical trials. The minimum recommended sequences include: (i) parameter-matched precontrast and postcontrast inversion recovery-prepared, isotropic 3D T1-weighted gradient-recalled echo; (ii) axial 2D T2-weighted turbo spin-echo acquired after contrast injection and before postcontrast 3D T1-weighted images to control timing of images after contrast administration; (iii) precontrast, axial 2D T2-weighted fluid-attenuated inversion recovery; and (iv) precontrast, axial 2D, 3-directional diffusion-weighted images. Recommended ranges of sequence parameters are provided for both 1.5 T and 3 T MR systems. PMID:26250565

  7. PATTERN RECOGNITION/EXPERT SYSTEM FOR IDENTIFICATION OF TOXIC COMPOUNDS FROM LOW RESOLUTION MASS SPECTRA

    EPA Science Inventory

    An empirical rule-based pattern recognition/expert system for classifying, estimating molecular weights and identifying low resolution mass spectra of toxic and other organic compounds has been developed and evaluated. he system was designed to accommodate low concentration spect...

  8. Low-resolution mid-infrared reflection analysis for discernment of contaminants in seed cotton

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Contaminants often decrease cotton quality, which subsequently decrease cotton profitability. In this research, a low-resolution mid-infrared reflection instrument was designed and constructed by using only four different wavelengths to accomplish good separation of cotton samples from 14 contaminan...

  9. Low resolution radar digital interface. [with data recorder for precipitation measurements

    NASA Technical Reports Server (NTRS)

    1973-01-01

    This document describes the design and operation of a low resolution radar data recording system for precipitation measurements. This system records a full azimuth scan on seven track magnetic tapes every five minutes. It is designed to operate on a continuous basis with operator intervention required only for changing tape reels and calibration.

  10. EXPERT SYSTEM FOR ESTIMATING MOLECULAR WEIGHTS OF VOLATILE ORGANIC COMPOUNDS FROM LOW RESOLUTION MASS SPECTRA

    EPA Science Inventory

    MAXMASS, the highest mass with an intensity of 5% of the base peak in a low resolution mass spectrum, has been found to be linearly correlated with the true molecular weights of 400 randomly selected spectra, yielding a family of parallel lines. imple exert system using MAXMASS h...

  11. Low Resolution Visible Reflectance Spectrum for NEA (357439) 2004 BL86

    NASA Astrophysics Data System (ADS)

    Franco, Lorenzo

    2015-07-01

    Low resolution spectroscopic observations of the near- Earth asteroid (357439) 2004 BL86 were acquired during the flyby of 2015 January 26. The spectrum analysis shows that its taxonomic class is very close to that of 4 Vesta in the visible wavelength.

  12. Is the restricted ketogenic diet a viable alternative to the standard of care for managing malignant brain cancer?

    PubMed

    Seyfried, Thomas N; Marsh, Jeremy; Shelton, Laura M; Huysentruyt, Leanne C; Mukherjee, Purna

    2012-07-01

    Malignant brain cancer persists as a major disease of morbidity and mortality. The failure to recognize brain cancer as a disease of energy metabolism has contributed in large part to the failure in management. As long as brain tumor cells have access to glucose and glutamine, the disease will progress. The current standard of care provides brain tumors with access to glucose and glutamine. The high fat low carbohydrate ketogenic diet (KD) will target glucose availability and possibly that of glutamine when administered in carefully restricted amounts to reduce total caloric intake and circulating levels of glucose. The restricted KD (RKD) targets major signaling pathways associated with glucose and glutamine metabolism including the IGF-1/PI3K/Akt/Hif pathway. The RKD is anti-angiogenic, anti-invasive, anti-inflammatory, and pro-apoptotic when evaluated in mice with malignant brain cancer. The therapeutic efficacy of the restricted KD can be enhanced when combined with drugs that also target glucose and glutamine. Therapeutic efficacy of the RKD was also seen against malignant gliomas in human case reports. Hence, the RKD can be an effective non-toxic therapeutic option to the current standard of care for inhibiting the growth and invasive properties of malignant brain cancer. PMID:21885251

  13. EasyTopo: A toolbox for rapid diffuse optical topography based on a standard template of brain atlas

    NASA Astrophysics Data System (ADS)

    Tian, Fenghua; Lin, Zi-Jing; Liu, Hanli

    2013-03-01

    Diffuse optical topography remains a valid tool in functional near infrared spectroscopy (fNIRS) since it avoids solving the forward and inverse computational problems, which are encountered in diffuse optical tomography. Topography is particularly useful when a sparse array of optodes is used and depth specificity is not the primary interest. We have developed an easy toolbox for diffuse optical topography ("EasyTopo") based on a standard template of brain atlas. EasyTopo approximates the cortical layer of the brain as a hemispherical surface. Therefore, the stereotaxic coordinates of the brain surface and the co-registered fNIRS measurements (channels) are converted into the spherical coordinates, where 2D angular interpolation of the channel-wise data is implemented to obtain a topographic image of brain activation in the latitude-longitude space. Then, the interpolated image is projected back onto the brain surface in the original 3D stereotaxic coordinates. Compared with the existing 3D topography methods, EasyTopo is more computationally efficient and does not require any data extrapolation. Another advantage of EasyTopo is that the data between two spatially adjacent channels are interpolated along their included angles (i.e., along the angular direction) rather than along a straight line going under the brain surface. The former geometry in principle matches better with the realistic brain structure than the latter one. EasyTopo has been validated with both simulation and human experiments. Now this toolbox is publically available.

  14. Of Primary Interest: Using Brain-Based Teaching Strategies to Create Supportive Early Childhood Environments that Address Learning Standards

    ERIC Educational Resources Information Center

    Schiller, Pam; Willis, Clarissa

    2008-01-01

    The authors remind teachers that standards are not intended to fence in creative teachers or become obstacles for learners with special needs. To help teachers optimize learning for all children, they review brained-based research findings such as the importance of safe environments, the effect of emotions on learning, the use of multisensory…

  15. Neural-network-based image resolution enhancement from a multiple of low-resolution images

    NASA Astrophysics Data System (ADS)

    Salari, Ezzatollah; Zhang, Shuangteng

    2003-03-01

    A neural network based image enhancement method is introduced to improve the image resolution from a sequence of low resolution image frames. Most of the existing methods reconstruct a high-resolution image from a multiple of low-resolution image frames by minimizing some established cost function using a mathematical technique. This method, however, uses an integrated recurrent neural network (IRNN) that is particularly designed to be capable of learning an optimal mapping from a multiple of low-resolution image frames to a high-resolution image through training. The IRNN consists of four feed-forward sub-networks working collectively with the ability of having a feedback of information from its output to input. As such, it is capable of both learning and searching the optimal solution in the solution space leading to high resolution images. Simulation results demonstrate that the proposed IRNN has good potential in solving image resolution enhancement problem, as it can adapt itself to the various conditions of the reconstruction problem by learning.

  16. An example-based face hallucination method for single-frame, low-resolution facial images.

    PubMed

    Park, Jeong-Seon; Lee, Seong-Whan

    2008-10-01

    This paper proposes a face hallucination method for the reconstruction of high-resolution facial images from single-frame, low-resolution facial images. The proposed method has been derived from example-based hallucination methods and morphable face models. First, we propose a recursive error back-projection method to compensate for residual errors, and a region-based reconstruction method to preserve characteristics of local facial regions. Then, we define an extended morphable face model, in which an extended face is composed of the interpolated high-resolution face from a given low-resolution face, and its original high-resolution equivalent. Then, the extended face is separated into an extended shape and an extended texture. We performed various hallucination experiments using the MPI, XM2VTS, and KF databases, compared the reconstruction errors, structural similarity index, and recognition rates, and showed the effects of face detection errors and shape estimation errors. The encouraging results demonstrate that the proposed methods can improve the performance of face recognition systems. Especially the proposed method can enhance the resolution of single-frame, low-resolution facial images. PMID:18784029

  17. X-ray structure determination using low-resolution electron microscopy maps for molecular replacement

    PubMed Central

    Jackson, Ryan N.; McCoy, Airlie J.; Terwilliger, Thomas C.; Read, Randy J.; Wiedenheft, Blake

    2015-01-01

    Structures of multi-subunit macromolecular machines are primarily determined by either electron microscopy (EM) or X-ray crystallography. In many cases, a structure for a complex can be obtained at low resolution (at a coarse level of detail) with EM and at higher resolution (with finer detail) by X-ray crystallography. The integration of these two structural techniques is becoming increasingly important for generating atomic models of macromolecular complexes. A low-resolution EM image can be a powerful tool for obtaining the "phase" information that is missing from an X-ray crystallography experiment, however integration of EM and X-ray diffraction data has been technically challenging. Here we present a step-by-step protocol that explains how low-resolution EM maps can be placed in the crystallographic unit cell by molecular replacement, and how initial phases computed from the placed EM density are extended to high resolution by averaging maps over non-crystallographic symmetry. As the resolution gap between EM and X-ray crystallography continues to narrow, the use of EM maps to help with X-ray crystal structure determination, as described in this protocol, will become increasingly effective. PMID:26226459

  18. Abnormal brain activation and connectivity to standardized disorder-related visual scenes in social anxiety disorder.

    PubMed

    Heitmann, Carina Yvonne; Feldker, Katharina; Neumeister, Paula; Zepp, Britta Maria; Peterburs, Jutta; Zwitserlood, Pienie; Straube, Thomas

    2016-04-01

    Our understanding of altered emotional processing in social anxiety disorder (SAD) is hampered by a heterogeneity of findings, which is probably due to the vastly different methods and materials used so far. This is why the present functional magnetic resonance imaging (fMRI) study investigated immediate disorder-related threat processing in 30 SAD patients and 30 healthy controls (HC) with a novel, standardized set of highly ecologically valid, disorder-related complex visual scenes. SAD patients rated disorder-related as compared with neutral scenes as more unpleasant, arousing and anxiety-inducing than HC. On the neural level, disorder-related as compared with neutral scenes evoked differential responses in SAD patients in a widespread emotion processing network including (para-)limbic structures (e.g. amygdala, insula, thalamus, globus pallidus) and cortical regions (e.g. dorsomedial prefrontal cortex (dmPFC), posterior cingulate cortex (PCC), and precuneus). Functional connectivity analysis yielded an altered interplay between PCC/precuneus and paralimbic (insula) as well as cortical regions (dmPFC, precuneus) in SAD patients, which emphasizes a central role for PCC/precuneus in disorder-related scene processing. Hyperconnectivity of globus pallidus with amygdala, anterior cingulate cortex (ACC) and medial prefrontal cortex (mPFC) additionally underlines the relevance of this region in socially anxious threat processing. Our findings stress the importance of specific disorder-related stimuli for the investigation of altered emotion processing in SAD. Disorder-related threat processing in SAD reveals anomalies at multiple stages of emotion processing which may be linked to increased anxiety and to dysfunctionally elevated levels of self-referential processing reported in previous studies. Hum Brain Mapp 37:1559-1572, 2016. © 2016 Wiley Periodicals, Inc. PMID:26806013

  19. Comparison of Low Resolution Electromagnetic Tomography Imaging Between Subjects With Mild and Severe Obstructive Sleep Apnea Syndrome: A Preliminary Study

    PubMed Central

    Lee, Hyun-Kwon; Shin, Hyun-Sil; Hong, Seok-Chan

    2008-01-01

    Objective The purpose of this study was to identify the regions of the brain associated with recurrent nocturnal chronic hypoxic episodes in patients with untreated obstructive sleep apnea syndrome (OSAS) using low-resolution electromagnetic tomography (LORETA) and quantitative electroencephalography (QEEG). Methods Nocturnal polysomnograph (NPSG) and subsequent morning electroencephalograph (EEG) were measured in 20 subjects with OSAS. Mild (n=10 ages 39.5±12.1 years) and severe (n=10 ages 41.7±13.6 years) right-handed male OSAS subjects were selected by interview and questionnaires including the NPSG, Beck Depression Inventory, Beck Anxiety Inventory, Epworth Sleepiness Scale, and Pittsburgh Sleep Quality Index. The LORETA and QEEG were compared between the severe and mild OSAS groups by frequency bands (delta 1-3 Hz, theta 4-7 Hz, alpha 8-12 Hz, beta1 13-18 Hz, beta2 19-21 Hz, beta3 22-30 Hz, and total 1-30 Hz) made by spectral analysis during resting with the eyes closed. Results The LORETA analysis showed decreased alpha activity at the right posterior cingulate gyrus (Brodmann area 23) in cases with severe OSAS compared to mild OSAS (p<0.05). For the QEEG, the absolute power of the alpha activity (8-12 Hz) was decreased in P3 (p=0.047), PZ (p=0.039) and O2 (p=0.04) in cases with severe OSAS compared to mild OSAS cases. The LORETA and QEEG analyses had similar results with regard to band, activation and location. Conclusion The decreased activity of the alpha frequency in the right posterior cingulate gyrus, in patients with severe OSAS compared to those with mild OSAS, suggests that chronic repeated short-term hypoxia during sleep, in OSAS, could provoke cortical brain dysfunction associated with cognitive dysfunction such as memory and attention. PMID:20046408

  20. Autonomous Motion Segmentation of Multiple Objects in Low Resolution Video Using Variational Level Sets

    SciTech Connect

    Moelich, M

    2003-11-18

    This report documents research that was done during a ten week internship in the Sapphire research group at the Lawrence Livermore National Laboratory during the Summer of 2003. The goal of the study was to develop an algorithm that is capable of isolating (segmenting) moving objects in low resolution video sequences. This capability is currently being developed by the Sapphire research group as the first stage in a longer term video data mining project. This report gives a chronological account of what ideas were tried in developing the algorithm and what was learned from each attempt. The final version of the algorithm, which is described in detail, gives good results and is fast.

  1. Monitoring the Continuing Spectral Evolution of Nova Delphini 2013 (V339 Del) with Low Resolution Spectroscopy

    NASA Astrophysics Data System (ADS)

    Mooers, H. D.; Wiethoff, W. S.; Evich, A.

    2016-02-01

    The continuing spectral evolution of Nova Delphini 2013 is presented with low-resolution spectroscopy collected with a 100 line per millimeter diffraction grating. Spectra were collected on 3 July, 2014 and 14 September, 2015, +321 and +759 days after peak visible brightness on 16 August, 2013. Imaging system was mounted on an equatorially-mounted, 14-inch Schmidt-Cassegrain telescope. The continuum is no longer visible in the spectra, however, Oiii (5007 Å) and Ha (6563 Å) are prominent and Nii (5755), Hg (4340 Å) and Ciii/Niii (4640 Å) can still be discerned at +759 days.

  2. TGS[underscore]FIT: Image reconstruction software for quantitative, low-resolution tomographic assays

    SciTech Connect

    Estep, R J

    1993-01-01

    We developed the computer program TGS[underscore]FIT to aid in researching the tomographic gamma scanner method of nondestructive assay. This software, written in C-programming, language, implements a full Beer's Law attenuation correction in reconstructing low-resolution emission tomograms. The attenuation coefficients for the corrections are obtained by reconstructing a transmission tomogram of the same resolution. The command-driven interface, combined with (crude) simulation capabilities and command file control, allows design studies to be performed in a semi-automated manner.

  3. Compound classification by computer treatment of low resolution mass spectra - Application to geochemical and environmental problems.

    NASA Technical Reports Server (NTRS)

    Smith, D. H.; Eglinton, G.

    1972-01-01

    A description is given of a development of computer analysis of low-resolution chromatographic-mass spectrometric data, which provides a preliminary classification of an unknown spectrum as a listing of candidate classes of compounds. This procedure, referred to as COMSOC (Classification of Mass Spectra on Computers), operates by converting an incoming unknown mass spectrum into a simplified key word which is then compared with each of the key words held in its reference file. The advantages of COMSOC in characterizing complex mixtures are emphasized.

  4. Metastatic melanoma to the brain: surgery and radiation is still the standard of care.

    PubMed

    Nicholas, Sarah; Mathios, Dimitrios; Jackson, Christopher; Lim, Michael

    2013-06-01

    Malignant melanoma with brain metastases remains a difficult disease to treat. Patients presenting with disease affecting the central nervous system (CNS) have a poor prognosis. Treatment depends on a number of factors, including the size and number of lesions, performance status, comorbidities, and presenting symptoms. Physicians and patients must weigh risks and benefits of treatments, with the main goal of palliating symptoms and decreasing the risk of neurological death. Opinions throughout the country vary, but first-line treatment for brain metastases is local therapy involving either craniotomy or stereotactic radiosurgery (SRS) using CyberKnife or Gamma Knife, with or without whole brain radiation therapy (WBRT). Clinical trials remain another option for patients, with chemotherapy reserved for patients who have exhausted other options. There has been a recent surge in knowledge regarding the pathophysiology and treatment of metastatic melanoma leading to recent FDA approval in 2011 of new drugs: ipilimumab, a novel immune therapy, and vemurafenib, which blocks the MAP Kinase pathway. These drugs have the potential to treat patients with metastatic melanoma to the brain but are still undergoing clinical investigation. Despite these recent advances, the prognosis is poor, with few patients able to achieve durable and long-lasting response. Treatment for patients with brain metastases continues to lag behind treatment of other diseases, partly due to their exclusion from early clinical trials. PMID:23504304

  5. Amyloids in solid-state nuclear magnetic resonance: potential causes of the usually low resolution.

    PubMed

    Espargaró, Alba; Busquets, Maria Antònia; Estelrich, Joan; Sabate, Raimon

    2015-01-01

    Amyloids are non-crystalline and insoluble, which imply that the classical structural biology tools, ie, X-ray crystallography and solution nuclear magnetic resonance (NMR), are not suitable for their analysis. In the last years, solid-state NMR (ssNMR) has emerged as an alternative tool to decrypt the structural signatures of amyloid fibrils, providing major contributions to our understanding of molecular structures of amyloids such as β-amyloid peptide associated with Alzheimer's disease or fungal prions, among others. Despite this, the wide majority of amyloid fibrils display low resolution by ssNMR. Usually, this low resolution has been attributed to a high disorder or polymorphism of the fibrils, suggesting the existence of diverse elementary β-sheet structures. Here, we propose that a single β-sheet structure could be responsible for the broadening of the line widths in the ssNMR spectra. Although the fibrils and fibers consist of a single elementary structure, the angle of twist of each individual fibril in the mature fiber depends on the number of individual fibrils as well as the fibril arrangement in the final mature fiber. Thus, a wide range of angles of twist could be observed in the same amyloid sample. These twist variations involve changes in amino acid alignments that could be enough to limit the ssNMR resolution. PMID:26635473

  6. Amyloids in solid-state nuclear magnetic resonance: potential causes of the usually low resolution

    PubMed Central

    Espargaró, Alba; Busquets, Maria Antònia; Estelrich, Joan; Sabate, Raimon

    2015-01-01

    Amyloids are non-crystalline and insoluble, which imply that the classical structural biology tools, ie, X-ray crystallography and solution nuclear magnetic resonance (NMR), are not suitable for their analysis. In the last years, solid-state NMR (ssNMR) has emerged as an alternative tool to decrypt the structural signatures of amyloid fibrils, providing major contributions to our understanding of molecular structures of amyloids such as β-amyloid peptide associated with Alzheimer’s disease or fungal prions, among others. Despite this, the wide majority of amyloid fibrils display low resolution by ssNMR. Usually, this low resolution has been attributed to a high disorder or polymorphism of the fibrils, suggesting the existence of diverse elementary β-sheet structures. Here, we propose that a single β-sheet structure could be responsible for the broadening of the line widths in the ssNMR spectra. Although the fibrils and fibers consist of a single elementary structure, the angle of twist of each individual fibril in the mature fiber depends on the number of individual fibrils as well as the fibril arrangement in the final mature fiber. Thus, a wide range of angles of twist could be observed in the same amyloid sample. These twist variations involve changes in amino acid alignments that could be enough to limit the ssNMR resolution. PMID:26635473

  7. Progress in low-resolution ab initio phasing with CrowdPhase

    PubMed Central

    Jorda, Julien; Sawaya, Michael R.; Yeates, Todd O.

    2016-01-01

    Ab initio phasing by direct computational methods in low-resolution X-ray crystallography is a long-standing challenge. A common approach is to consider it as two subproblems: sampling of phase space and identification of the correct solution. While the former is amenable to a myriad of search algorithms, devising a reliable target function for the latter problem remains an open question. Here, recent developments in CrowdPhase, a collaborative online game powered by a genetic algorithm that evolves an initial population of individuals with random genetic make-up (i.e. random phases) each expressing a phenotype in the form of an electron-density map, are presented. Success relies on the ability of human players to visually evaluate the quality of these maps and, following a Darwinian survival-of-the-fittest concept, direct the search towards optimal solutions. While an initial study demonstrated the feasibility of the approach, some important crystallographic issues were overlooked for the sake of simplicity. To address these, the new CrowdPhase includes consideration of space-group symmetry, a method for handling missing amplitudes, the use of a map correlation coefficient as a quality metric and a solvent-flattening step. Performances of this installment are discussed for two low-resolution test cases based on bona fide diffraction data. PMID:26960132

  8. An Adaptive Control Method for Ros-Drill Cellular Microinjector with Low-Resolution Encoder

    PubMed Central

    Zhang, Zhenyu; Olgac, Nejat

    2013-01-01

    A novel control methodology which uses a low-resolution encoder is presented for a cellular microinjection technology called the Ros-Drill (rotationally oscillating drill). It is developed primarily for ICSI (intracytoplasmic sperm injection) operations, with the objective of generating a desired oscillatory motion at the tip of a micro glass pipette. It is an inexpensive setup, which creates high-frequency (higher than 500 Hz) and small-amplitude (around 0.2 deg) rotational oscillations at the tip of an injection pipette. These rotational oscillations enable the pipette to drill into cell membranes with minimum biological damage. Such a motion control procedure presents no particular difficulty when it uses sufficiently precise motion sensors. However, size, costs, and accessibility of technology to the hardware components severely constrain the sensory capabilities. Consequently, the control mission and the trajectory tracking are adversely affected. This paper presents two contributions: (a) a dedicated novel adaptive feedback control method to achieve a satisfactory trajectory tracking capability. We demonstrate via experiments that the tracking of the harmonic rotational motion is achieved with desirable fidelity; (b) some important analytical features and related observations associated with the controlled harmonic motion which is created by the low-resolution feedback control structure.

  9. Progress in low-resolution ab initio phasing with CrowdPhase.

    PubMed

    Jorda, Julien; Sawaya, Michael R; Yeates, Todd O

    2016-03-01

    Ab initio phasing by direct computational methods in low-resolution X-ray crystallography is a long-standing challenge. A common approach is to consider it as two subproblems: sampling of phase space and identification of the correct solution. While the former is amenable to a myriad of search algorithms, devising a reliable target function for the latter problem remains an open question. Here, recent developments in CrowdPhase, a collaborative online game powered by a genetic algorithm that evolves an initial population of individuals with random genetic make-up (i.e. random phases) each expressing a phenotype in the form of an electron-density map, are presented. Success relies on the ability of human players to visually evaluate the quality of these maps and, following a Darwinian survival-of-the-fittest concept, direct the search towards optimal solutions. While an initial study demonstrated the feasibility of the approach, some important crystallographic issues were overlooked for the sake of simplicity. To address these, the new CrowdPhase includes consideration of space-group symmetry, a method for handling missing amplitudes, the use of a map correlation coefficient as a quality metric and a solvent-flattening step. Performances of this installment are discussed for two low-resolution test cases based on bona fide diffraction data. PMID:26960132

  10. FitEM2EM--tools for low resolution study of macromolecular assembly and dynamics.

    PubMed

    Frankenstein, Ziv; Sperling, Joseph; Sperling, Ruth; Eisenstein, Miriam

    2008-01-01

    Studies of the structure and dynamics of macromolecular assemblies often involve comparison of low resolution models obtained using different techniques such as electron microscopy or atomic force microscopy. We present new computational tools for comparing (matching) and docking of low resolution structures, based on shape complementarity. The matched or docked objects are represented by three dimensional grids where the value of each grid point depends on its position with regard to the interior, surface or exterior of the object. The grids are correlated using fast Fourier transformations producing either matches of related objects or docking models depending on the details of the grid representations. The procedures incorporate thickening and smoothing of the surfaces of the objects which effectively compensates for differences in the resolution of the matched/docked objects, circumventing the need for resolution modification. The presented matching tool FitEM2EMin successfully fitted electron microscopy structures obtained at different resolutions, different conformers of the same structure and partial structures, ranking correct matches at the top in every case. The differences between the grid representations of the matched objects can be used to study conformation differences or to characterize the size and shape of substructures. The presented low-to-low docking tool FitEM2EMout ranked the expected models at the top. PMID:18974836

  11. Standardized Environmental Enrichment Supports Enhanced Brain Plasticity in Healthy Rats and Prevents Cognitive Impairment in Epileptic Rats

    PubMed Central

    Kouchi, Hayet Y.; Bodennec, Jacques; Morales, Anne; Georges, Béatrice; Bonnet, Chantal; Bouvard, Sandrine; Sloviter, Robert S.; Bezin, Laurent

    2013-01-01

    Environmental enrichment of laboratory animals influences brain plasticity, stimulates neurogenesis, increases neurotrophic factor expression, and protects against the effects of brain insult. However, these positive effects are not constantly observed, probably because standardized procedures of environmental enrichment are lacking. Therefore, we engineered an enriched cage (the Marlau™ cage), which offers: (1) minimally stressful social interactions; (2) increased voluntary exercise; (3) multiple entertaining activities; (4) cognitive stimulation (maze exploration), and (5) novelty (maze configuration changed three times a week). The maze, which separates food pellet and water bottle compartments, guarantees cognitive stimulation for all animals. Compared to rats raised in groups in conventional cages, rats housed in Marlau™ cages exhibited increased cortical thickness, hippocampal neurogenesis and hippocampal levels of transcripts encoding various genes involved in tissue plasticity and remodeling. In addition, rats housed in Marlau™ cages exhibited better performances in learning and memory, decreased anxiety-associated behaviors, and better recovery of basal plasma corticosterone level after acute restraint stress. Marlau™ cages also insure inter-experiment reproducibility in spatial learning and brain gene expression assays. Finally, housing rats in Marlau™ cages after severe status epilepticus at weaning prevents the cognitive impairment observed in rats subjected to the same insult and then housed in conventional cages. By providing a standardized enriched environment for rodents during housing, the Marlau™ cage should facilitate the uniformity of environmental enrichment across laboratories. PMID:23342033

  12. Standardized environmental enrichment supports enhanced brain plasticity in healthy rats and prevents cognitive impairment in epileptic rats.

    PubMed

    Fares, Raafat P; Belmeguenai, Amor; Sanchez, Pascal E; Kouchi, Hayet Y; Bodennec, Jacques; Morales, Anne; Georges, Béatrice; Bonnet, Chantal; Bouvard, Sandrine; Sloviter, Robert S; Bezin, Laurent

    2013-01-01

    Environmental enrichment of laboratory animals influences brain plasticity, stimulates neurogenesis, increases neurotrophic factor expression, and protects against the effects of brain insult. However, these positive effects are not constantly observed, probably because standardized procedures of environmental enrichment are lacking. Therefore, we engineered an enriched cage (the Marlau™ cage), which offers: (1) minimally stressful social interactions; (2) increased voluntary exercise; (3) multiple entertaining activities; (4) cognitive stimulation (maze exploration), and (5) novelty (maze configuration changed three times a week). The maze, which separates food pellet and water bottle compartments, guarantees cognitive stimulation for all animals. Compared to rats raised in groups in conventional cages, rats housed in Marlau™ cages exhibited increased cortical thickness, hippocampal neurogenesis and hippocampal levels of transcripts encoding various genes involved in tissue plasticity and remodeling. In addition, rats housed in Marlau™ cages exhibited better performances in learning and memory, decreased anxiety-associated behaviors, and better recovery of basal plasma corticosterone level after acute restraint stress. Marlau™ cages also insure inter-experiment reproducibility in spatial learning and brain gene expression assays. Finally, housing rats in Marlau™ cages after severe status epilepticus at weaning prevents the cognitive impairment observed in rats subjected to the same insult and then housed in conventional cages. By providing a standardized enriched environment for rodents during housing, the Marlau™ cage should facilitate the uniformity of environmental enrichment across laboratories. PMID:23342033

  13. Improved image reconstruction of low-resolution multichannel phase contrast angiography.

    PubMed

    P Krishnan, Akshara; Joy, Ajin; Paul, Joseph Suresh

    2016-01-01

    In low-resolution phase contrast magnetic resonance angiography, the maximum intensity projected channel images will be blurred with consequent loss of vascular details. The channel images are enhanced using a stabilized deblurring filter, applied to each channel prior to combining the individual channel images. The stabilized deblurring is obtained by the addition of a nonlocal regularization term to the reverse heat equation, referred to as nonlocally stabilized reverse diffusion filter. Unlike reverse diffusion filter, which is highly unstable and blows up noise, nonlocal stabilization enhances intensity projected parallel images uniformly. Application to multichannel vessel enhancement is illustrated using both volunteer data and simulated multichannel angiograms. Robustness of the filter applied to volunteer datasets is shown using statistically validated improvement in flow quantification. Improved performance in terms of preserving vascular structures and phased array reconstruction in both simulated and real data is demonstrated using structureness measure and contrast ratio. PMID:26835501

  14. A model-based approach for detection of objects in low resolution passive millimeter wave images

    NASA Technical Reports Server (NTRS)

    Kasturi, Rangachar; Tang, Yuan-Liang; Devadiga, Sadashiva

    1993-01-01

    A model-based vision system to assist the pilots in landing maneuvers under restricted visibility conditions is described. The system was designed to analyze image sequences obtained from a Passive Millimeter Wave (PMMW) imaging system mounted on the aircraft to delineate runways/taxiways, buildings, and other objects on or near runways. PMMW sensors have good response in a foggy atmosphere, but their spatial resolution is very low. However, additional data such as airport model and approximate position and orientation of aircraft are available. These data are exploited to guide our model-based system to locate objects in the low resolution image and generate warning signals to alert the pilots. Also analytical expressions were derived from the accuracy of the camera position estimate obtained by detecting the position of known objects in the image.

  15. Single-Shot Rotational Raman Thermometry for Turbulent Flames Using a Low-Resolution Bandwidth Technique

    NASA Technical Reports Server (NTRS)

    Kojima, Jun; Nguyen, Quang-Viet

    2007-01-01

    An alternative optical thermometry technique that utilizes the low-resolution (order 10(exp 1)/cm) pure-rotational spontaneous Raman scattering of air is developed to aid single-shot multiscalar measurements in turbulent combustion studies. Temperature measurements are realized by correlating the measured envelope bandwidth of the pure-rotational manifold of the N2/O2 spectrum with a theoretical prediction of a species-weighted bandwidth. By coupling this thermometry technique with conventional vibrational Raman scattering for species determination, we demonstrate quantitative spatially resolved, single-shot measurements of the temperature and fuel/oxidizer concentrations in a high-pressure turbulent Cf4-air flame. Our technique provides not only an effective means of validating other temperature measurement methods, but also serves as a secondary thermometry technique in cases where the anti-Stokes vibrational N2 Raman signals are too low for a conventional vibrational temperature analysis.

  16. Compact low resolution spectrograph, an imaging and long slit spectrograph for robotic telescopes

    SciTech Connect

    Rabaza, O.; Zeman, J.; Hudec, R.; Faculty of Electrical Engineering, Czech Technical University, Technicka 2, Praha 6 ; Sabau-Graziati, L.

    2013-11-15

    The COmpact LOw REsolution Spectrograph (COLORES) is a compact and lightweight (13 kg) f/8 imaging spectrograph designed for robotic telescopes, now installed and operating on the TELMA, a rapid-slewing 60 cm telescope of the BOOTES-2 observatory in Málaga (Spain). COLORES is a multi-mode instrument that enables the observer to seamlessly switch between low-dispersion spectroscopy and direct imaging modes during an observation. In this paper, we describe the instrument and its development, from the initial scientific requirements through the optical design process to final configuration with theoretical performance calculations. The mechanical and electronic design is described, methods of calibration are discussed and early laboratory and scientific results are shown.

  17. [The radial velocity measurement accuracy of different spectral type low resolution stellar spectra at different signal-to-noise ratio].

    PubMed

    Wang, Feng-Fei; Luo, A-Li; Zhao, Yong-Heng

    2014-02-01

    The radial velocity of the star is very important for the study of the dynamics structure and chemistry evolution of the Milky Way, is also an useful tool for looking for variable or special objects. In the present work, we focus on calculating the radial velocity of different spectral types of low-resolution stellar spectra by adopting a template matching method, so as to provide effective and reliable reference to the different aspects of scientific research We choose high signal-to-noise ratio (SNR) spectra of different spectral type stellar from the Sloan Digital Sky Survey (SDSS), and add different noise to simulate the stellar spectra with different SNR. Then we obtain theradial velocity measurement accuracy of different spectral type stellar spectra at different SNR by employing a template matching method. Meanwhile, the radial velocity measurement accuracy of white dwarf stars is analyzed as well. We concluded that the accuracy of radial velocity measurements of early-type stars is much higher than late-type ones. For example, the 1-sigma standard error of radial velocity measurements of A-type stars is 5-8 times as large as K-type and M-type stars. We discuss the reason and suggest that the very narrow lines of late-type stars ensure the accuracy of measurement of radial velocities, while the early-type stars with very wide Balmer lines, such as A-type stars, become sensitive to noise and obtain low accuracy of radial velocities. For the spectra of white dwarfs stars, the standard error of radial velocity measurement could be over 50 km x s(-1) because of their extremely wide Balmer lines. The above conclusion will provide a good reference for stellar scientific study. PMID:24822441

  18. Original Protocol Using Computed Tomographic Angiography for Diagnosis of Brain Death: A Better Alternative to Standard Two-Phase Technique?

    PubMed

    Sawicki, Marcin; So?ek-Pastuszka, Joanna; Jurczyk, Krzysztof; Skrzywanek, Piotr; Guzi?ski, Maciej; Czajkowski, Zenon; Ma?ko, Witold; Burzy?ska, Ma?gorzata; Safranow, Krzysztof; Poncyljusz, Wojciech; Walecka, Anna; Rowi?ski, Olgierd; Walecki, Jerzy; Bohatyrewicz, Romuald

    2015-01-01

    BACKGROUND The application of computed tomographic angiography (CTA) for the diagnosis of brain death (BD) is limited because of the low sensitivity of the commonly used two-phase method consisting of assessing arterial and venous opacification at the 60th second after contrast injection. The hypothesis was that a reduction in the scanning delay might increase the sensitivity of the test. Therefore, an original technique using CTA was introduced and compared with catheter angiography as a reference. MATERIAL AND METHODS In a prospective multicenter trial, 84 clinically brain-dead patients were examined using CTA and catheter angiography. The sensitivities of original CTA technique, involving an arterial assessment at the 25th second and a venous assessment at the 40th second, and the standard CTA, involving an arterial and venous assessment at the 60th second, were compared to catheter angiography. RESULTS Catheter angiography results were consistent with the clinical diagnosis of BD in all cases. In comparison to catheter angiography, the sensitivity of original CTA technique was 0.93 (95%CI, 0.85-0.97; p<0.001) and 0.57 (95%CI, 0.46-0.68; p<0.001) for the standard protocol. The differences were statistically significant (p=0.03 for original CTA and p<0.001 for standard CTA). Decompressive craniectomy predisposes to a false-negative CTA result with a relative risk of 3.29 (95% CI, 1.76-5.81; p<0.001). CONCLUSIONS Our original technique using CTA for the assessment of the cerebral arteries during the arterial phase and the deep cerebral veins with a delay of 15 seconds is a highly sensitive test for the diagnosis of BD. This method may be a better alternative to the commonly used technique. PMID:26250464

  19. A concept to standardize raw biosignal transmission for brain-computer interfaces.

    PubMed

    Breitwieser, Christian; Neuper, Christa; Müller-Putz, Gernot R

    2011-01-01

    With this concept we introduced the attempt of a standardized interface called TiA to transmit raw biosignals. TiA is able to deal with multirate and block-oriented data transmission. Data is distinguished by different signal types (e.g., EEG, EOG, NIRS, …), whereby those signals can be acquired at the same time from different acquisition devices. TiA is built as a client-server model. Multiple clients can connect to one server. Information is exchanged via a control- and a separated data connection. Control commands and meta information are transmitted over the control connection. Raw biosignal data is delivered using the data connection in a unidirectional way. For this purpose a standardized handshaking protocol and raw data packet have been developed. Thus, an abstraction layer between hardware devices and data processing was evolved facilitating standardization. PMID:22255797

  20. Development and use of a kinetic FDG-PET dataset simulated from the MNI standard brain

    NASA Astrophysics Data System (ADS)

    Schottlander, David; Guimond, Alexandre; Pan, Xiao-Bo; Brady, Michael; Declerck, Jérôme; Collins, Louis; Evans, Alan C.; Reilhac, Anthonin

    2006-03-01

    Simulated data is an important tool for evaluation of reconstruction and image processing algorithms in the frequent absence of ground truth, in-vivo data from living subjects. This is especially true in the case of dynamic PET studies, in which counting statistics of the volume can vary widely over the time-course of the acquisition. Realistic simulated data-sets which model anatomy and physiology, and make explicit the spatial and temporal image acquisition characteristics, facilitate experimentation with a wide range of the conditions anticipated in practice, and which can severely challenge algorithm performance and reliability. As a first example, we have developed a realistic dynamic FDG-PET data-set using the PET-SORTEO Monte Carlo simulation code and the MNI digital brain phantom. The phantom is a three-dimensional data-set that defines the spatial distribution of different tissues. Time activity curves were calculated using an impulse response function specified by generally accepted rate constants, convolved with an input function obtained by blood sampling, and assigned to grey and white matter tissue regions. We created a dynamic PET study using PET-SORTEO configured to simulate an ECAT Exact HR+. The resulting sinograms were reconstructed with all corrections, using variations of FBP and OSEM. Having constructed the dynamic PET data-sets, we used them to evaluate the performance of intensity-based registration as part of a tool for quantifying hyper/hypo perfusion with particular application to analysis of brain dementia scans, and a study of the stability of kinetic parameter estimation.

  1. Peptide Peak Detection for Low Resolution MALDI-TOF Mass Spectrometry

    PubMed Central

    Yao, Jingwen; Utsunomiya, Shin-ichi; Kajihara, Shigeki; Tabata, Tsuyoshi; Aoshima, Ken; Oda, Yoshiya; Tanaka, Koichi

    2014-01-01

    A new peak detection method has been developed for rapid selection of peptide and its fragment ion peaks for protein identification using tandem mass spectrometry. The algorithm applies classification of peak intensities present in the defined mass range to determine the noise level. A threshold is then given to select ion peaks according to the determined noise level in each mass range. This algorithm was initially designed for the peak detection of low resolution peptide mass spectra, such as matrix-assisted laser desorption/ionization Time-of-Flight (MALDI-TOF) mass spectra. But it can also be applied to other type of mass spectra. This method has demonstrated obtaining a good rate of number of real ions to noises for even poorly fragmented peptide spectra. The effect of using peak lists generated from this method produces improved protein scores in database search results. The reliability of the protein identifications is increased by finding more peptide identifications. This software tool is freely available at the Mass++ home page (http://www.first-ms3d.jp/english/achievement/software/).

  2. Using Sculptor and Situs for simultaneous assembly of atomic components into low-resolution shapes.

    PubMed

    Birmanns, Stefan; Rusu, Mirabela; Wriggers, Willy

    2011-03-01

    We describe an integrated software system called Sculptor that combines visualization capabilities with molecular modeling algorithms for the analysis of multi-scale data sets. Sculptor features extensive special purpose visualization techniques that are based on modern GPU programming and are capable of representing complex molecular assemblies in real-time. The integration of graphics and modeling offers several advantages. The user interface not only eases the usually steep learning curve of pure algorithmic techniques, but it also permits instant analysis and post-processing of results, as well as the integration of results from external software. Here, we implemented an interactive peak-selection strategy that enables the user to explore a preliminary score landscape generated by the colors tool of Situs. The interactive placement of components, one at a time, is advantageous for low-resolution or ambiguously shaped maps, which are sometimes difficult to interpret by the fully automatic peak selection of colors. For the subsequent refinement of the preliminary models resulting from both interactive and automatic peak selection, we have implemented a novel simultaneous multi-body docking in Sculptor and Situs that softly enforces shape complementarities between components using the normalization of the cross-correlation coefficient. The proposed techniques are freely available in Situs version 2.6 and Sculptor version 2.0. PMID:21078392

  3. Stealth carriers for low-resolution structure determination of membrane proteins in solution.

    PubMed

    Maric, Selma; Skar-Gislinge, Nicholas; Midtgaard, Søren; Thygesen, Mikkel B; Schiller, Jürgen; Frielinghaus, Henrich; Moulin, Martine; Haertlein, Michael; Forsyth, V Trevor; Pomorski, Thomas Günther; Arleth, Lise

    2014-02-01

    Structural studies of membrane proteins remain a great experimental challenge. Functional reconstitution into artificial nanoscale bilayer disc carriers that mimic the native bilayer environment allows the handling of membrane proteins in solution. This enables the use of small-angle scattering techniques for fast and reliable structural analysis. The difficulty with this approach is that the carrier discs contribute to the measured scattering intensity in a highly nontrivial fashion, making subsequent data analysis challenging. Here, an elegant solution to circumvent the intrinsic complexity brought about by the presence of the carrier disc is presented. In combination with small-angle neutron scattering (SANS) and the D2O/H2O-based solvent contrast-variation method, it is demonstrated that it is possible to prepare specifically deuterated carriers that become invisible to neutrons in 100% D2O at the length scales relevant to SANS. These `stealth' carrier discs may be used as a general platform for low-resolution structural studies of membrane proteins using well established data-analysis tools originally developed for soluble proteins. PMID:24531466

  4. Laplace Inversion of Low-Resolution NMR Relaxometry Data Using Sparse Representation Methods

    PubMed Central

    Berman, Paula; Levi, Ofer; Parmet, Yisrael; Saunders, Michael; Wiesman, Zeev

    2013-01-01

    Low-resolution nuclear magnetic resonance (LR-NMR) relaxometry is a powerful tool that can be harnessed for characterizing constituents in complex materials. Conversion of the relaxation signal into a continuous distribution of relaxation components is an ill-posed inverse Laplace transform problem. The most common numerical method implemented today for dealing with this kind of problem is based on L2-norm regularization. However, sparse representation methods via L1 regularization and convex optimization are a relatively new approach for effective analysis and processing of digital images and signals. In this article, a numerical optimization method for analyzing LR-NMR data by including non-negativity constraints and L1 regularization and by applying a convex optimization solver PDCO, a primal-dual interior method for convex objectives, that allows general linear constraints to be treated as linear operators is presented. The integrated approach includes validation of analyses by simulations, testing repeatability of experiments, and validation of the model and its statistical assumptions. The proposed method provides better resolved and more accurate solutions when compared with those suggested by existing tools. © 2013 Wiley Periodicals, Inc. Concepts Magn Reson Part A 42A: 72–88, 2013. PMID:23847452

  5. Replica Exchange Improves Sampling in Low-Resolution Docking Stage of RosettaDock

    PubMed Central

    Zhang, Zhe; Lange, Oliver F.

    2013-01-01

    Many protein-protein docking protocols are based on a shotgun approach, in which thousands of independent random-start trajectories minimize the rigid-body degrees of freedom. Another strategy is enumerative sampling as used in ZDOCK. Here, we introduce an alternative strategy, ReplicaDock, using a small number of long trajectories of temperature replica exchange. We compare replica exchange sampling as low-resolution stage of RosettaDock with RosettaDock's original shotgun sampling as well as with ZDOCK. A benchmark of 30 complexes starting from structures of the unbound binding partners shows improved performance for ReplicaDock and ZDOCK when compared to shotgun sampling at equal or less computational expense. ReplicaDock and ZDOCK consistently reach lower energies and generate significantly more near-native conformations than shotgun sampling. Accordingly, they both improve typical metrics of prediction quality of complex structures after refinement. Additionally, the refined ReplicaDock ensembles reach significantly lower interface energies and many previously hidden features of the docking energy landscape become visible when ReplicaDock is applied. PMID:24009670

  6. Newly Identified Carbon Stars from Sources with Unusual IRAS Low-Resolution Spectra

    NASA Astrophysics Data System (ADS)

    Chen, P. S.; Shan, H. G.

    2012-07-01

    The 11.2 ?m SiC feature in either emission or absorption in the infrared is an important indicator for identification of carbon stars. Sources whose infrared spectra are sorted in Group U of the Infrared Astronomical Satellite (IRAS) low-resolution spectrum (LRS) are good samples for finding objects with the 11.2 ?m SiC feature. Therefore, we have carefully checked all spectra in Group U of the LRS. We have found 13 new objects, which probably have SiC emission, sometimes with unusually broad features, that are presumed to be carbon-rich objects. In addition, their evolutionary types are also estimated from IRAS and Two Micron All Sky Survey two-color diagrams. Besides finding 13 new carbon-rich objects, another important result in this paper is that four sources are estimated as new extreme carbon stars (ECSs) and five previously known carbon stars sorted in the Group U of the IRAS LRS are also estimated as ECSs.

  7. Lamost Observations in the Kepler Field. I. Database of Low-resolution Spectra

    NASA Astrophysics Data System (ADS)

    De Cat, P.; Fu, J. N.; Ren, A. B.; Yang, X. H.; Shi, J. R.; Luo, A. L.; Yang, M.; Wang, J. L.; Zhang, H. T.; Shi, H. M.; Zhang, W.; Dong, Subo; Catanzaro, G.; Corbally, C. J.; Frasca, A.; Gray, R. O.; Molenda-?akowicz, J.; Uytterhoeven, K.; Briquet, M.; Bruntt, H.; Frandsen, S.; Kiss, L.; Kurtz, D. W.; Marconi, M.; Niemczura, E.; Østensen, R. H.; Ripepi, V.; Smalley, B.; Southworth, J.; Szabó, R.; Telting, J. H.; Karoff, C.; Silva Aguirre, V.; Wu, Y.; Hou, Y. H.; Jin, G.; Zhou, X. L.

    2015-09-01

    The nearly continuous light curves with micromagnitude precision provided by the space mission Kepler are revolutionizing our view of pulsating stars. They have revealed a vast sea of low-amplitude pulsation modes that were undetectable from Earth. The long time base of Kepler light curves allows for the accurate determination of the frequencies and amplitudes of pulsation modes needed for in-depth asteroseismic modeling. However, for an asteroseismic study to be successful, the first estimates of stellar parameters need to be known and they cannot be derived from the Kepler photometry itself. The Kepler Input Catalog provides values for the effective temperature, surface gravity, and metallicity, but not always with sufficient accuracy. Moreover, information on the chemical composition and rotation rate is lacking. We are collecting low-resolution spectra for objects in the Kepler field of view with the Large Sky Area Multi-Object Fiber Spectroscopic Telescope (lamost, Xinglong observatory, China). All of the requested fields have now been observed at least once. In this paper, we describe those observations and provide a useful database for the whole astronomical community. ) located at the Xinglong observatory, China.

  8. Topographic Phase Recovery from Stacked ERS Interferometry and a Low-Resolution Digital Elevation Model

    NASA Technical Reports Server (NTRS)

    Sandwell, David T.; Sichoix, Lydie; Frey, Herbert V. (Technical Monitor)

    2000-01-01

    A hybrid approach to topographic recovery from ERS interferometry is developed and assessed. Tropospheric/ionospheric artifacts, imprecise orbital information, and layover are key issues in recovering topography and surface deformation from repeat-pass interferometry. Previously, we developed a phase gradient approach to stacking interferograms to reduce these errors and also to reduce the short-wavelength phase noise (see Sandwell arid Price [1998] and Appendix A). Here the method is extended to use a low-resolution digital elevation model to constrain long-wavelength phase errors and an iteration scheme to minimize errors in the computation of phase gradient. We demonstrate the topographic phase recovery on 16-m postings using 25 ERS synthetic aperture radar images from an area of southern California containing 2700 m of relief. On the basis of a comparison with 81 GPS monuments, the ERS derived topography has a typical absolute accuracy of better than 10 m except in areas of layover. The resulting topographic phase enables accurate two-pass, real-time interferometry even in mountainous areas where traditional phase unwrapping schemes fail. As an example, we form a topography-free (127-m perpendicular baseline) interferogram spanning 7.5 years; fringes from two major earthquakes and a seismic slip on the San Andreas Fault are clearly isolated.

  9. Low-resolution Spectroscopic study of Globular Clusters with Multiple Populations

    NASA Astrophysics Data System (ADS)

    Lim, Dongwook; Lee, Young-Wook

    2016-01-01

    Recent studies of stellar populations in globular clusters (GCs) are facing a new paradigm as more and more GCs are observed to have multiple populations. In order to investigate the origin of these multiple stellar populations, we have performed low-resolution spectroscopy for red giant branch stars in M22, NGC 288, NGC 362, NGC 1851, NGC 6266, NGC 6273, NGC 6626, NGC 6642, NGC 6723, and 47 Tuc. We find significant differences in CN band strength for every sample GCs. However, the differences in calcium abundance (HK' index) between CN-strong and CN-weak subpopulations are found only in M22, NGC 1851, and NGC 6273. This difference in heavy elements would imply that later generation stars were enriched by Type II supernovae. In addition, we find interesting differences in CN-CH relation among sample GCs. While CN and CH are anti-correlated in normal GCs, which show no difference in calcium abundance, they show positive correlations in M22 and NGC 6273. NGC 1851, however, shows no difference in CH between the two groups of stars with different CN strengths. We suggest that all of these systematic differences would be best explained by how strongly supernovae enrichment has contributed to the chemical evolution of these GCs.

  10. Low-resolution characterization of the 3D structure of the Euglena gracilis photoreceptor

    SciTech Connect

    Barsanti, Laura; Coltelli, Primo; Evangelista, Valtere; Passarelli, Vincenzo; Frassanito, Anna Maria; Vesentini, Nicoletta; Gualtieri, Paolo

    2008-10-24

    This paper deals with the first characterization of the structure of the photoreceptive organelle of the unicellular alga Euglena gracilis (Euglenophyta). This organelle has a three-dimensional organization consisting of up to 50 closely stacked membrane lamellae. Ionically induced unstacking of the photoreceptor lamellae revealed ordered arrays well suited to structural analysis by electron microscopy and image analysis, which ultimately yielded a low-resolution picture of the structure. Each lamella is formed by the photoreceptive membrane protein of the cell assembled within the membrane layer in a hexagonal lattice. The first order diffraction spots in the calculated Fourier transform reveals the presence of 6-fold symmetrized topography (better resolution about 90 A). The 2D and 3D structural data are very similar with those recently published on proteorodopsin, a membrane protein used by marine bacterio-plankton as light-driven proton pump. In our opinion these similarity indicate that a photoreceptive protein belonging to the same superfamily of proteorodopsin could form the Euglena photoreceptor.

  11. HUNTING THE PARENT OF THE ORPHAN STREAM: IDENTIFYING STREAM MEMBERS FROM LOW-RESOLUTION SPECTROSCOPY

    SciTech Connect

    Casey, Andrew R.; Da Costa, Gary; Keller, Stefan C.; Maunder, Elizabeth

    2013-02-10

    We present candidate K-giant members in the Orphan Stream that have been identified from low-resolution data taken with the AAOmega spectrograph on the Anglo-Australian Telescope. From modest signal-to-noise spectra and independent cuts in photometry, kinematics, gravity, and metallicity we yield self-consistent, highly probable stream members. We find a revised stream distance of 22.5 {+-} 2.0 kpc near the celestial equator and our kinematic signature peaks at V {sub GSR} = 82.1 {+-} 1.4 km s{sup -1}. The observed velocity dispersion of our most probable members is consistent with arising from the velocity uncertainties alone. This indicates that at least along this line of sight, the Orphan Stream is kinematically cold. Our data indicate an overall stream metallicity of [Fe/H] = -1.63 {+-} 0.19 dex which is more metal-rich than previously found and unbiased by spectral type. Furthermore, the significant metallicity dispersion displayed by our most probable members, {sigma}([Fe/H]) = 0.56 dex, suggests that the unidentified Orphan Stream parent is a dSph satellite. We highlight likely members for high-resolution spectroscopic follow-up.

  12. High-resolution land cover classification using low resolution global data

    NASA Astrophysics Data System (ADS)

    Carlotto, Mark J.

    2013-05-01

    A fusion approach is described that combines texture features from high-resolution panchromatic imagery with land cover statistics derived from co-registered low-resolution global databases to obtain high-resolution land cover maps. The method does not require training data or any human intervention. We use an MxN Gabor filter bank consisting of M=16 oriented bandpass filters (0-180°) at N resolutions (3-24 meters/pixel). The size range of these spatial filters is consistent with the typical scale of manmade objects and patterns of cultural activity in imagery. Clustering reduces the complexity of the data by combining pixels that have similar texture into clusters (regions). Texture classification assigns a vector of class likelihoods to each cluster based on its textural properties. Classification is unsupervised and accomplished using a bank of texture anomaly detectors. Class likelihoods are modulated by land cover statistics derived from lower resolution global data over the scene. Preliminary results from a number of Quickbird scenes show our approach is able to classify general land cover features such as roads, built up area, forests, open areas, and bodies of water over a wide range of scenes.

  13. Low-Resolution Vehicle Image Recognition Technology by Frame-Composition of Moving Images

    NASA Astrophysics Data System (ADS)

    Kanzawa, Yusuke; Kobayashi, Hiroki; Ohkawa, Takenao; Ito, Toshio

    Developing on-board automotive driver assistance systems aiming to alert drivers about driving environments, and possible collision with other vehicles has attracted a lot of attention lately. Especially, many researchers have suggested the forward vehicle recognition technology by a camera on vehicle. In the forward vehicle recognition, however, it is difficult to detect the features of vehicle from a distant vehicle image by conventional methods because the image is too low-resolution (LR). This paper presents vehicle image recognition technology for detecting of the features of a distant vehicle by frame-composition of moving images. To detect the vehicle features of a distant LR vehicle image, we use the moving images obtained from the camera on the vehicle, and utilize super-resolution (SR) image reconstruction. SR image reconstruction is to use signal processing techniques to obtain a high-resolution (or sequence) image from observed multiple LR images. Use of this technique on real road image, we show the effectiveness of the proposed techniques.

  14. Standard Guidelines for Publication of Deep Brain Stimulation Studies in Parkinson’s Disease (Guide4DBS-PD)

    PubMed Central

    Vitek, Jerrold L.; Lyons, Kelly E.; Bakay, Roy; Benabid, Alim-Louis; Deuschl, Guenther; Hallett, Mark; Kurlan, Roger; Pancrazio, Joseph J.; Rezai, Ali; Walter, Benjamin L.; Lang, Anthony E.

    2015-01-01

    While the use of deep brain stimulation (DBS) for the treatment of neurological disorders has risen substantially over the last decade, it is often difficult to compare the results from different studies due to the lack of consistent reporting of key study parameters. We present guidelines to standardize the reporting of clinical studies of DBS for Parkinson’s disease (PD). These guidelines provide a minimal set of required data elements to facilitate the interpretation and comparison of results across published clinical studies. The guidelines, summarized in the format of a checklist, may also have utility in the planning of clinical studies of DBS for PD as well as other neurological and psychiatric disorders. PMID:20544809

  15. Radiometric Calibration of High Resolution UAVSAR Data Using Low Resolution SRTM DEMs

    NASA Astrophysics Data System (ADS)

    Riel, B. V.; Simard, M.

    2010-12-01

    Airborne and spaceborne Synthetic Aperture Radar (SAR) backscatter data have the potential to retrieve information on forest structure, above-ground biomass, and moisture content. However, SAR backscatter data contain both geometric and radiometric distortions due to underlying topography and the radar viewing geometry. These distortions can significantly affect the estimation of various scientific quantities. For example, a backscatter error of 1 dB can result in a biomass estimation error on the order of 10-15 Mg/ha. Thus, science applications based on SAR backscatter require accurate absolute radiometric calibration. The calibration process for topography involves estimation of the local radar scattering area through knowledge of the imaged terrain, which is often obtained through digital elevation models (DEMs). For this study, we radiometrically calibrate high resolution UAVSAR L-band radar data over a temperate forest site in New Hampshire using a low resolution (30m) SRTM DEM. Different calibration methods were tested and compared. We found that homomorphic methods based on the local incidence or projection angle do not estimate the scattering area as well as heteromorphic methods utilizing DEM integration techniques. Errors in the area estimation resulted in calibration differences less than 0.5 dB. The impact of low DEM resolution on calibration performance was assessed using a Fourier analysis of a large range of topographic classes. Power spectra were computed for high-resolution, bare-earth airborne lidar DEMs acquired over steep, moderate, and flat terrain. Similar power spectra were computed for oversampled SRTM DEMs over the same terrain. Errors for an SRTM DEM associated with a particular topographic class could be quantified through a comparison of its power spectrum with that from the lidar. We present a Fourier based method to systematically propagate errors in slope and aspect estimations to radiometric calibration accuracy. The methodology was validated by comparing slope and aspect derived from SRTM and lidar DEMs.

  16. Low-Resolution Modeling of Dense Drainage Networks in Confining Layers.

    PubMed

    Pauw, P S; Van der Zee, S E A T M; Leijnse, A; Delsman, J R; De Louw, P G B; De Lange, W J; Oude Essink, G H P

    2015-01-01

    Groundwater-surface water (GW-SW) interaction in numerical groundwater flow models is generally simulated using a Cauchy boundary condition, which relates the flow between the surface water and the groundwater to the product of the head difference between the node and the surface water level, and a coefficient, often referred to as the "conductance." Previous studies have shown that in models with a low grid resolution, the resistance to GW-SW interaction below the surface water bed should often be accounted for in the parameterization of the conductance, in addition to the resistance across the surface water bed. Three conductance expressions that take this resistance into account were investigated: two that were presented by Mehl and Hill (2010) and the one that was presented by De Lange (1999). Their accuracy in low-resolution models regarding salt and water fluxes to a dense drainage network in a confined aquifer system was determined. For a wide range of hydrogeological conditions, the influence of (1) variable groundwater density; (2) vertical grid discretization; and (3) simulation of both ditches and tile drains in a single model cell was investigated. The results indicate that the conductance expression of De Lange (1999) should be used in similar hydrogeological conditions as considered in this paper, as it is better taking into account the resistance to flow below the surface water bed. For the cases that were considered, the influence of variable groundwater density and vertical grid discretization on the accuracy of the conductance expression of De Lange (1999) is small. PMID:25250661

  17. Pedestrian Detection and Tracking from Low-Resolution Unmanned Aerial Vehicle Thermal Imagery.

    PubMed

    Ma, Yalong; Wu, Xinkai; Yu, Guizhen; Xu, Yongzheng; Wang, Yunpeng

    2016-01-01

    Driven by the prominent thermal signature of humans and following the growing availability of unmanned aerial vehicles (UAVs), more and more research efforts have been focusing on the detection and tracking of pedestrians using thermal infrared images recorded from UAVs. However, pedestrian detection and tracking from the thermal images obtained from UAVs pose many challenges due to the low-resolution of imagery, platform motion, image instability and the relatively small size of the objects. This research tackles these challenges by proposing a pedestrian detection and tracking system. A two-stage blob-based approach is first developed for pedestrian detection. This approach first extracts pedestrian blobs using the regional gradient feature and geometric constraints filtering and then classifies the detected blobs by using a linear Support Vector Machine (SVM) with a hybrid descriptor, which sophisticatedly combines Histogram of Oriented Gradient (HOG) and Discrete Cosine Transform (DCT) features in order to achieve accurate detection. This research further proposes an approach for pedestrian tracking. This approach employs the feature tracker with the update of detected pedestrian location to track pedestrian objects from the registered videos and extracts the motion trajectory data. The proposed detection and tracking approaches have been evaluated by multiple different datasets, and the results illustrate the effectiveness of the proposed methods. This research is expected to significantly benefit many transportation applications, such as the multimodal traffic performance measure, pedestrian behavior study and pedestrian-vehicle crash analysis. Future work will focus on using fused thermal and visual images to further improve the detection efficiency and effectiveness. PMID:27023564

  18. LRS2: the new facility low resolution integral field spectrograph for the Hobby-Eberly telescope

    NASA Astrophysics Data System (ADS)

    Chonis, Taylor S.; Hill, Gary J.; Lee, Hanshin; Tuttle, Sarah E.; Vattiat, Brian L.

    2014-07-01

    The second generation Low Resolution Spectrograph (LRS2) is a new facility instrument for the Hobby-Eberly Telescope (HET). Based on the design of the Visible Integral-field Replicable Unit Spectrograph (VIRUS), which is the new flagship instrument for carrying out the HET Dark Energy Experiment (HETDEX), LRS2 provides integral field spectroscopy for a seeing-limited field of 12" x 6". For LRS2, the replicable design of VIRUS has been leveraged to gain broad wavelength coverage from 370 nm to 1.0 ?m, spread between two fiber-fed dual- channel spectrographs, each of which can operate as an independent instrument. The blue spectrograph, LRS2-B, covers 370 ? (nm) <= 470 and 460 <= ? (nm) <= 700 at fixed resolving powers of R = ?/?? ? 1900 and 1100, respectively, while the red spectrograph, LRS2-R, covers 650 <= ? (nm) <= 842 and 818 <= ? (nm) <= 1050 with both of its channels having R ? 1800. In this paper, we present a detailed description of the instrument's design in which we focus on the departures from the basic VIRUS framework. The primary modifications include the fore-optics that are used to feed the fiber integral field units at unity fill-factor, the cameras' correcting optics and detectors, and the volume phase holographic grisms. We also present a model of the instrument's sensitivity and a description of specific science cases that have driven the design of LRS2, including systematically studying the spatially resolved properties of extended Ly? blobs at 2 < z < 3. LRS2 will provide a powerful spectroscopic follow-up platform for large surveys such as HETDEX.

  19. A Low-Resolution Spectroscopic Exploration of Puzzling OGLE Variable Stars

    NASA Astrophysics Data System (ADS)

    Pietrukowicz, P.; Latour, M.; Angeloni, R.; di Mille, F.; Soszy?ski, I.; Udalski, A.; Germanà, C.

    2015-03-01

    We present the results of a spectroscopic follow-up of various puzzling variable objects detected in the OGLE-III Galactic disk and bulge fields. The sample includes mainly short-period multi-mode pulsating stars that could not have been unambiguously classified as either ? Sct or ? Cep type stars based on photometric data only, also stars with irregular fluctuations mimicking cataclysmic variables and stars with dusty shells, and periodic variables displaying brightenings in their light curves that last for more than half of the period. The obtained low-resolution spectra show that all observed short-period pulsators are of ? Sct type, the stars with irregular fluctuations are young stellar objects, and the objects with regular brightenings are A type stars or very likely Ap stars with strong magnetic field responsible for the presence of bright caps around magnetic poles on their surface. We also took spectra of objects designated OGLE-GD-DSCT-0058 and OGLE-GD-CEP-0013. An estimated effective temperature of 33 000 K in OGLE-GD-DSCT-0058 indicates that it cannot be a ? Sct type variable. This very short-period (0.01962 d) high-amplitude (0.24 mag in the I-band) object remains a mystery. It may represent a new class of variable stars. The spectrum of OGLE-GD-CEP-0013 confirms that this is a classical Cepheid despite a peculiar shape of its light curve. The presented results will help in proper classification of variable objects in the OGLE Galaxy Variability Survey.

  20. Classification of Volcanic Eruptions on Io and Earth Using Low-Resolution Remote Sensing Data

    NASA Technical Reports Server (NTRS)

    Davies, A. G.; Keszthelyi, L. P.

    2005-01-01

    Two bodies in the Solar System exhibit high-temperature active volcanism: Earth and Io. While there are important differences in the eruptions on Earth and Io, in low-spatial-resolution data (corresponding to the bulk of available and foreseeable data of Io), similar styles of effusive and explosive volcanism yield similar thermal flux densities. For example, a square metre of an active pahoehoe flow on Io looks very similar to a square metre of an active pahoehoe flow on Earth. If, from observed thermal emission as a function of wavelength and change in thermal emission with time, the eruption style of an ionian volcano can be constrained, estimates of volumetric fluxes can be made and compared with terrestrial volcanoes using techniques derived for analysing terrestrial remotely-sensed data. In this way we find that ionian volcanoes fundamentally differ from their terrestrial counterparts only in areal extent, with Io volcanoes covering larger areas, with higher volumetric flux. Io outbursts eruptions have enormous implied volumetric fluxes, and may scale with terrestrial flood basalt eruptions. Even with the low-spatial resolution data available it is possible to sometimes constrain and classify eruption style both on Io and Earth from the integrated thermal emission spectrum. Plotting 2 and 5 m fluxes reveals the evolution of individual eruptions of different styles, as well as the relative intensity of eruptions, allowing comparison to be made from individual eruptions on both planets. Analyses like this can be used for interpretation of low-resolution data until the next mission to the jovian system. For a number of Io volcanoes (including Pele, Prometheus, Amirani, Zamama, Culann, Tohil and Tvashtar) we do have high/moderate resolution imagery to aid determination of eruption mode from analyses based only on low spatial-resolution data.

  1. RESEARCH PAPER: Automated estimation of stellar fundamental parameters from low resolution spectra: the PLS method

    NASA Astrophysics Data System (ADS)

    Zhang, Jian-Nan; Luo, A.-Li; Zhao, Yong-Heng

    2009-06-01

    PLS (Partial Least Squares regression) is introduced into an automatic estimation of fundamental stellar spectral parameters. It extracts the most correlative spectral component to the parameters (Teff, log g and [Fe/H]), and sets up a linear regression function from spectra to the corresponding parameters. Considering the properties of stellar spectra and the PLS algorithm, we present a piecewise PLS regression method for estimation of stellar parameters, which is composed of one PLS model for Teff, and seven PLS models for log g and [Fe/H] estimation. Its performance is investigated by large experiments on flux calibrated spectra and continuum normalized spectra at different signal-to-noise ratios (SNRs) and resolutions. The results show that the piecewise PLS method is robust for spectra at the medium resolution of 0.23 nm. For low resolution 0.5 nm and 1 nm spectra, it achieves competitive results at higher SNR. Experiments using ELODIE spectra of 0.23 nm resolution illustrate that our piecewise PLS models trained with MILES spectra are efficient for O ~ G stars: for flux calibrated spectra, the systematic offsets are 3.8%, 0.14 dex, and -0.09 dex for Teff, log g and [Fe/H], with error scatters of 5.2%, 0.44 dex and 0.38 dex, respectively; for continuum normalized spectra, the systematic offsets are 3.8%, 0.12dex, and -0.13dex for Teff, log g and [Fe/H], with error scatters of 5.2%, 0.49 dex and 0.41 dex, respectively. The PLS method is rapid, easy to use and does not rely as strongly on the tightness of a parameter grid of templates to reach high precision as Artificial Neural Networks or minimum distance methods do.

  2. Low-resolution continuum source simultaneous multi-element electrothermal atomic absorption spectrometry: steps into practice

    NASA Astrophysics Data System (ADS)

    Katskov, Dmitri

    2015-03-01

    The theory and practical problems of continuum source simultaneous multi-element electrothermal atomic absorption spectrometry (SMET AAS) are discussed by the example of direct analysis of underground water. The experimental methodology is based on pulse vaporization of the sample in a fast heated graphite tube and measurement of transient absorption of continuum spectrum radiation from D2 and Xe lamps within 200-400 nm wavelengths range with a low resolution spectral instrument and linear charge-coupled device. The setup permits the acquisition of 200 spectra during 1 s atomization pulse. Respective data matrix absorbance vs wavelength/time is employed for the quantification of elements in the sample. The calculation algorithm developed includes broad band and continuum background correction, linearization of function absorbance vs. concentration of atomic vapor and integration of thus modified absorbance at the resonance lines of the elements to be determined. Practical application shows that the method can be employed for the direct simultaneous determination of about 20 elements above microgram per liter level within 3-5 orders of the magnitude concentration range. The investigated sources of measurement errors are mainly associated with the atomization and vapor transportation problems, which are aggravated for the simultaneous release of major and minor sample constituents. Respective corrections concerning the selection of analytical lines, optimal sampling volume, matrix modification and cleaning of the atomizer have been introduced in the SMET AAS analytical technology. Under the optimized experimental conditions the calibration curves in Log-Log coordinates for all the investigated analytes in the single or multi-element reference solutions are approximated by the first order equations. The use of these equations as permanent characteristics of the setup enables instant quantification of Al, Ca, Co, Cr, Cu, Fe, Mg, Mn and Ni in the underground water samples with an accuracy of 30%.

  3. Detections of diffuse interstellar bands in the SDSS low-resolution spectra

    NASA Astrophysics Data System (ADS)

    Yuan, H. B.; Liu, X. W.

    2012-09-01

    Diffuse interstellar bands (DIBs) have been discovered for almost a century, but their nature remains one of the most challenging problems in the astronomical spectroscopy. Most recent work to identify and investigate the properties and carriers of DIBs concentrates on high-resolution spectroscopy of selected sight-lines. In this paper, we report detections of DIBs in the Sloan Digital Sky Survey (SDSS) low-resolution spectra of a large sample of Galactic stars. Using a template subtraction method, we have successfully identified the DIBs ??5780, 6283 in the SDSS spectra of a sample of about 2000 stars and measured their strengths and radial velocities. The sample is by far the largest ever assembled. The targets span a large range of reddening, E(B - V) ˜ 0.2-1.0, and are distributed over a large sky area and involve a wide range of stellar parameters (effective temperature, surface gravity and metallicity), confirming that the carriers of DIBs are ubiquitous in the diffuse interstellar medium (ISM). The sample is used to investigate relations between strengths of DIBs and magnitudes of line-of-sight extinction, yielding results [i.e. EW(5780) = 0.61 × E(B - V) and EW(6283) = 1.26 × E(B - V)] consistent with previous studies. DIB features have also been detected in the commissioning spectra of the Guoshoujing Telescope [the Large Sky Area Multi-Object Fibre Spectroscopic Telescope (LAMOST)] of resolving power similar to that of the SDSS. Detections of DIBs of hundreds of thousands of stars are expected from the on-going and up-coming large-scale spectroscopic surveys such as Radial Velocity Experiment, SDSS III and LAMOST, particularly from the LAMOST Digital Sky Survey of the Galactic Anticentre (DSS-GAC). Such a huge data base will provide an unprecedented opportunity to study the demographical distribution and nature of DIBs as well as using DIBs to probe the distribution and properties of the ISM and the dust extinction.

  4. Multi-object spectroscopy on the Hobby-Eberly Telescope low-resolution spectrograph

    NASA Astrophysics Data System (ADS)

    Wolf, Marsha J.; Hill, Gary J.; Mitsch, Wolfgang; Hessman, Frederic V.; Altmann, Werner; Thompson, Keith L.

    2000-08-01

    The low resolution spectrograph (LRS) is the first facility instrument on the 9.2m Hobby-Eberly Telescope (HET). The LRS has three operational modes: imaging, long-slit spectroscopy and multi-object spectroscopy (MOS). We present the design and early operations performance of the LRS MOS unit, which provides 13 slitless, each 1.3 arcsec by 15 arcsec, on 19.6 arcsec centers, within the 4 arcmin field of view of the HET. This type of remotely configurable unit was chosen over the more conventional slit masks due to the queue scheduling of the HET, and the instrument's remote location at the prime focus of the telescope. A restricted envelope around the HET focus at the LRS port forced a very compact design. The MOS unit has miniature mechanisms base don custom cross- roller stages and 0.25 mm pitch lead-screws. Geared stepper motors with 10 mm diameters drive the 13 axes at 0.8 micron per step. The precision of the mechanism is far greater than required by the HET plate scale of 205 microns per arcsec, but result in a robust unit. The slitlets were fabricated at the University of Texas by shadow-masking the slit area with a wire and vacuum depositing aluminum onto the silica substrates. Both sides are then coated with MgF2 which serves as an antireflection coating and a protective layer. Web-based software is available for optimizing the orientation of the MOS unit and the placement of slitlets on objects in the field. These setup scan be down loaded to the unit for configuration outside of the beam while the HET is slewing to its next target in the queue, or while the LRS is used in imaging mode for setup on faint objects. The preliminary results presented here are from one commissioning run with the MOS, where the unit appears to be meeting performance specifications.

  5. Mediterranean region cyclone climatology and low resolution GCM capabilities in its reproduction (directly and using statistical downscaling technique)

    SciTech Connect

    Rubinatein, K.; Bardin, M.

    1997-12-31

    The present study is aimed at the investigation of the low resolution GCM of the Hydrometcentre of Russia capability to describe the climatological properties of Mediterranean cyclones. For this, we calculate certain cyclone statistics (at 500mb and surface) by empirical data and from numerical experiments (several decades both), and perform comparative analysis of climatology means and variability.

  6. A Convenient Low-Resolution NMR Method for the Determination of the Molecular Weight of Soybean Oil-Based Polymers

    Technology Transfer Automated Retrieval System (TEKTRAN)

    By studying a series of soybean oil based polymers, using low resolution nuclear magnetic resonance (NMR) spectroscopy, an easy method to study molecular weight was developed. The relationship between a polymer’s molecular weight and the instrument’s response can be correlated in a linear relations...

  7. A comparison study of tropical Pacific ocean state estimation: Low-resolution assimilation vs. high-resolution simulation.

    NASA Astrophysics Data System (ADS)

    Fu, Weiwei; Zhu, Jiang; Zhou, Guangqing; Wang, Huijun

    2005-03-01

    A comparison study is performed to contrast the improvements in the tropical Pacific oceanic state of a low-resolution model respectively via data assimilation and by an increase in horizontal resolution. A low resolution model (LR) (1°lat by 2°lon) and a high-resolution model (HR) (0.5°lat by 0.5°lon) are employed for the comparison. The authors perform 20-yr numerical experiments and analyze the annual mean fields of temperature and salinity. The results indicate that the low-resolution model with data assimilation behaves better than the high-resolution model in the estimation of ocean large-scale features. From 1990 to 2000, the average of HR’s RMSE (root-mean-square error) relative to independent Tropical Atmosphere Ocean project (TAO) mooring data at randomly selected points is 0.97°C compared to a RMSE of 0.56°C for LR with temperature assimilation. Moreover, the LR with data assimilation is more frugal in computation. Although there is room to improve the high-resolution model, the low-resolution model with data assimilation may be an advisable choice in achieving a more realistic large-scale state of the ocean at the limited level of information provided by the current observational system.

  8. Implementation of pigment-dispersing factor-immunoreactive neurons in a standardized atlas of the brain of the cockroach Leucophaea maderae.

    PubMed

    Wei, Hongying; el Jundi, Basil; Homberg, Uwe; Stengl, Monika

    2010-10-15

    The cockroach Leucophaea maderae is an established model in circadian rhythm research. Its circadian clock is located in the accessory medulla of the brain. Pigment-dispersing factor-immunoreactive (PDF-ir) neurons of the accessory medulla act as circadian pacemakers controlling locomotor activity rhythms. To characterize the neuronal network of the circadian system in L. maderae, the PDF-ir neurons were implemented into a standardized three-dimensional atlas of the cockroach brain. Serial confocal images from 20 wholemount brains were used for the construction of the atlas comprising 21 neuropils. Two different standardization protocols were employed: the iterative shape averaging (ISA) procedure using an affine transformation followed by iterative non-rigid registrations, and the virtual insect brain (VIB) protocol employing local non-rigid transformations after global and local rigid transformations. Quantitative analysis of the 20 brains revealed that volumes of the accessory medulla are directly correlated with the volumes of the medulla, the protocerebral bridge, and the upper division of the central body, suggesting functional connections among these neuropils. For a standardized reconstruction of the circadian pacemaker network, the ISA protocol was used to register PDF-ir neurons in the standard cockroach brain. The registration revealed that two PDF-ir arborization areas in the brain are highly interconnected with other PDF-ir projection sites and appear to be contacted both by fibers in the posterior and the anterior optic commissures. The distances between PDF-ir branching areas show specific numerical relationships that might be physiologically relevant for temporal encoding. PMID:20878779

  9. Standard Operating Procedures, ethical and legal regulations in BTB (Brain/Tissue/Bio) banking: what is still missing?

    PubMed

    Ravid, Rivka

    2008-06-01

    The use of human biological specimens in scientific research is the focus of current international public and professional concern and a major issue in bioethics in general. Brain/Tissue/Bio banks (BTB-banks) are a rapid developing sector; each of these banks acts locally as a steering unit for the establishment of the local Standard Operating Procedures (SOPs) and the legal regulations and ethical guidelines to be followed in the procurement and dissemination of research specimens. An appropriat Code of Conduct is crucial to a successful operation of the banks and the research application they handle. What are we still missing ? (1) Adequate funding for research BTB-banks. (2) Standard evaluation protocls for audit of BTB-bank performance. (3) Internationally accepted SOP's which will facilitate exchange and sharing of specimens and data with the scientific community. (4) Internationally accepted Code of Conduct. In the present paper we review the most pressing organizational, methodological, medico-legal and ethical issues involved in BTB-banking; funding, auditing, procurement, management/handling, dissemination and sharing of specimens, confidentiality and data protection, genetic testing, "financial gain" and safety measures. Taking into consideration the huge variety of the specimens stored in different repositories and the enormous differences in medico-legal systems and ethics regulations in different countries it is strongly recommend that the health-care systems and institutions who host BTB-Banks will put more efforts in getting adequate funding for the infrastructure and daily activities. The BTB-banks should define evaluation protocols, SOPs and their Code of Conduct. This in turn will enable the banks to share the collected specimens and data with the largest possible number of researchers and aim at a maximal scientific spin-off and advance in public health research. PMID:17985213

  10. Standard Operating Procedures, ethical and legal regulations in BTB (Brain/Tissue/Bio) banking: what is still missing?

    PubMed

    Ravid, Rivka

    2008-09-01

    The use of human biological specimens in scientific research is the focus of current international public and professional concern and a major issue in bioethics in general. Brain/Tissue/Bio banks (BTB-banks) are a rapid developing sector; each of these banks acts locally as a steering unit for the establishment of the local Standard Operating Procedures (SOPs) and the legal regulations and ethical guidelines to be followed in the procurement and dissemination of research specimens. An appropriat Code of Conduct is crucial to a successful operation of the banks and the research application they handle. What are we still missing ? (1) Adequate funding for research BTB-banks. (2) Standard evaluation protocls for audit of BTB-bank performance. (3) Internationally accepted SOP's which will facilitate exchange and sharing of specimens and data with the scientific community. (4) Internationally accepted Code of Conduct. In the present paper we review the most pressing organizational, methodological, medico-legal and ethical issues involved in BTB-banking; funding, auditing, procurement, management/handling, dissemination and sharing of specimens, confidentiality and data protection, genetic testing, "financial gain" and safety measures. Taking into consideration the huge variety of the specimens stored in different repositories and the enormous differences in medico-legal systems and ethics regulations in different countries it is strongly recommend that the health-care systems and institutions who host BTB-Banks will put more efforts in getting adequate funding for the infrastructure and daily activities. The BTB-banks should define evaluation protocols, SOPs and their Code of Conduct. This in turn will enable the banks to share the collected specimens and data with the largest possible number of researchers and aim at a maximal scientific spin-off and advance in public health research. PMID:18584309

  11. On the utility of low resolution IUE spectroscopy of the 2800 A Mg II lines as a stellar chromosphere indicator

    NASA Technical Reports Server (NTRS)

    Smith, Graeme H.; Burstein, David; Fanelli, Michael N.; O'Connell, Robert W.; Wu, C.-C.

    1991-01-01

    Low resolution IUE spectroscopy of the 2800-A Mg II h and k lines is shown to provide a useful means for documenting chromospheric activity among relatively young dwarf stars. An index I(Mg II) has been defined which measures the integrated flux in the region 2784-2814 A relative to the flux interpolated from nearby comparison regions. Values of this index have been derived from low resolution IUE spectra for a sample of field dwarfs for which Ca II H and K line indices have been published as part of the Mount Wilson HK program. The large range in chromospheric activity among field dwarfs that is exhibited by the Mount Wilson Ca II S index is found to also be reflected by the lower resolution I(Mg II) index. Using an age calibration of Ca II emission line strengths derived by Barry, it is found that the value of I(Mg II) can be used to distinguish between dwarfs younger and older than 3 Gyr. The low resolution nature of the I(Mg II) index means that it holds potential for use as an age diagnostic for stellar population studies. Among dwarfs of age greater than 3 Gyr there is some evidence that this Mg II index is affected by line blanketing.

  12. On the utility of low resolution IUE spectroscopy of the 2800 A Mg II lines as a stellar chromosphere indicator

    SciTech Connect

    Smith, G.H.; Burstein, D.; Fanelli, M.N.; O'Connell, R.W.; Wu, C.C. Arizona State Univ., Tempe Virginia Univ., Charlottesville Computer Sciences Corp., Baltimore, MD )

    1991-02-01

    Low resolution IUE spectroscopy of the 2800-A Mg II h and k lines is shown to provide a useful means for documenting chromospheric activity among relatively young dwarf stars. An index I(Mg II) has been defined which measures the integrated flux in the region 2784-2814 A relative to the flux interpolated from nearby comparison regions. Values of this index have been derived from low resolution IUE spectra for a sample of field dwarfs for which Ca II H and K line indices have been published as part of the Mount Wilson HK program. The large range in chromospheric activity among field dwarfs that is exhibited by the Mount Wilson Ca II S index is found to also be reflected by the lower resolution I(Mg II) index. Using an age calibration of Ca II emission line strengths derived by Barry, it is found that the value of I(Mg II) can be used to distinguish between dwarfs younger and older than 3 Gyr. The low resolution nature of the I(Mg II) index means that it holds potential for use as an age diagnostic for stellar population studies. Among dwarfs of age greater than 3 Gyr there is some evidence that this Mg II index is affected by line blanketing. 27 refs.

  13. Cerebral Blood Flow Estimation Using Classification Techniques On A Sequence Of Low Resolution Tomographic Evolutive Images

    NASA Astrophysics Data System (ADS)

    Chan, Marie; Aguilar-Martin, Joseph; Boulanouar, Kader; Celsis, Pierre; Marc-Vergnes, Jean P.

    1989-05-01

    In order to improve the performance of the instrumental variable method (IVM) in calculating regional cerebral blood flow (rCBF) using Single Photon Emission Computed Tomography (SPELT), and inert diffusible tracer such as 133Xe, we use Learning Algorithms for Multivariate Data Analysis (LAMDA) to classify the voxels of the images of local concentrations in the brain. The LAMDA method correctly distinguished between extra and intra-cerebral voxels. However the topography of the intra-cerebral classes did not match the Regions Of Interest (ROI) defined on an anatomical basis. Provided that all the intra-cerebral classes contaminated by bone and air passage artefact were rejected, the results given by the NM are in good agreement with those derived by the bolus distribution principle. We thus conclude that LAMDA methods can improve the reliability of images of CBF estimates.

  14. Monitoring environmental change in the Andes based on low resolution time series analysis

    NASA Astrophysics Data System (ADS)

    Tote, C.; Swinnen, E.; Beringhs, K.; Govers, G.

    2012-04-01

    Environmental change is an important issue in the Andes region and it is unknown to what extent the ongoing processes are a consequence of human impact and/or climate change. The objectives of this research are to study vegetation dynamics in the Andes region based on time series analysis of SPOT-Vegetation, NOAA-AVHRR and MODIS derived NDVI at low spatial but high temporal resolution, and to recognize to which extent this variability can be attributed to either climatic variability or human induced impacts through assimilation of satellite derived NDVI and rainfall data. Monthly rainfall estimates were available from the European Centre for Medium-Range Weather Forecasts (ECMWF) through MeteoConsult and the Monitoring Agricultural ResourceS (MARS) unit. Deviations from the 'average' situation were calculated for the NDVI time series using the Standardized Difference Vegetation Index (SDVI) and for the precipitation time series using the Standardized Precipitation Index (SPI). Correlation analysis between NDVI and SPI is performed in order to identify the temporal scale at which the environment is most sensitive to precipitation anomalies (best lag). Trends in SDVI and SPI are investigated using least square regression, taking into account the accumulated rainfall anomalies over the best lag. Hot spots of human induced environmental change are detected by subtraction of the precipitation induced signal on vegetation dynamics. The model can be used to predict possible effects of climate change in areas most sensible to trends in precipitation.

  15. A New Method for Characterizing Very Low-Mass Companions with Low-Resolution Near-Infrared Spectroscopy

    NASA Astrophysics Data System (ADS)

    Rice, Emily L.; Oppenheimer, Rebecca; Zimmerman, Neil; Roberts, Lewis C.; Hinkley, Sasha

    2015-05-01

    We present a new and computationally efficient method for characterizing very low-mass companions using low-resolution (R ˜ 30), near-infrared (YJH) spectra from high-contrast imaging campaigns with integral field spectrograph (IFS) units. We conduct a detailed quantitative comparison of the efficacy of this method through tests on simulated data comparable in spectral coverage and resolution to the currently operating direct-imaging systems around the world. In particular, we simulate Project 1640 data as an example of the use, accuracy, and precision of this technique. We present results from comparing simulated spectra of M, L, and T dwarfs with a large and finely sampled grid of synthetic spectra using Markov-chain Monte Carlo techniques. We determine the precision and accuracy of effective temperature and surface gravity inferred from fits to PHOENIX dusty and cond, which we find reproduce the low-resolution spectra of all objects within the adopted flux uncertainties. Uncertainties in effective temperature decrease from ± 100-500 K for M dwarfs to as small as ± 30 K for some L and T spectral types. Surface gravity is constrained to within 0.2-0.4 dex for mid-L through T dwarfs, but uncertainties are as large as 1.0 dex or more for M dwarfs. Results for effective temperature from low-resolution YJH spectra generally match predictions from published spectral type-temperature relationships except for L-T transition objects and young objects. Single-band spectra (i.e., narrower wavelength coverage) result in larger uncertainties and often discrepant results, suggesting that high-contrast IFS observing campaigns can compensate for low spectral resolution by expanding the wavelength coverage for reliable characterization of detected companions. We find that S/N ˜ 10 is sufficient to characterize temperature and gravity as well as possible given the model grid. Most relevant for direct-imaging campaigns targeting young primary stars is our finding that low-resolution near-infrared spectra of known young objects, compared to field objects of the same spectral type, result in similar best-fit surface gravities but lower effective temperatures, highlighting the need for better observational and theoretical understanding of the entangled effects of temperature, gravity, and dust on near-infrared spectra in cool low-gravity atmospheres.

  16. Visual analysis of trash bin processing on garbage trucks in low resolution video

    NASA Astrophysics Data System (ADS)

    Sidla, Oliver; Loibner, Gernot

    2015-03-01

    We present a system for trash can detection and counting from a camera which is mounted on a garbage collection truck. A working prototype has been successfully implemented and tested with several hours of real-world video. The detection pipeline consists of HOG detectors for two trash can sizes, and meanshift tracking and low level image processing for the analysis of the garbage disposal process. Considering the harsh environment and unfavorable imaging conditions, the process works already good enough so that very useful measurements from video data can be extracted. The false positive/false negative rate of the full processing pipeline is about 5-6% at fully automatic operation. Video data of a full day (about 8 hrs) can be processed in about 30 minutes on a standard PC.

  17. The scientifically substantiated art of teaching: A study in the development of standards in the new academic field of neuroeducation (mind, brain, and education science)

    NASA Astrophysics Data System (ADS)

    Tokuhama-Espinosa, Tracey Noel

    Concepts from neuroeducation, commonly referred in the popular press as "brain-based learning," have been applied indiscreetly and inconsistently to classroom teaching practices for many years. While standards exist in neurology, psychology and pedagogy, there are no agreed upon standards in their intersection, neuroeducation, and a formal bridge linking the fields is missing. This study used grounded theory development to determine the parameters of the emerging neuroeducational field based on a meta-analysis of the literature over the past 30 years, which included over 2,200 documents. This research results in a new model for neuroeducation. The design of the new model was followed by a Delphi survey of 20 international experts from six different countries that further refined the model contents over several months of reflection. Finally, the revised model was compared to existing information sources, including popular press, peer review journals, academic publications, teacher training textbooks and the Internet, to determine to what extent standards in neuroeducation are met in the current literature. This study determined that standards in the emerging field, now labeled Mind, Brain, and Education: The Science of Teaching and Learning after the Delphi rounds, are the union of standards in the parent fields of neuroscience, psychology, and education. Additionally, the Delphi expert panel agreed upon the goals of the new discipline, its history, the thought leaders, and a model for judging quality information. The study culminated in a new model of the academic discipline of Mind, Brain, and Education science, which explains the tenets, principles and instructional guidelines supported by the meta-analysis of the literature and the Delphi response.

  18. Free-viewpoint video synthesis from mixed resolution multi-view images and low resolution depth maps

    NASA Astrophysics Data System (ADS)

    Emori, Takaaki; Tehrani, Mehrdad P.; Takahashi, Keita; Fujii, Toshiaki

    2015-03-01

    Streaming application of multi-view and free-viewpoint video is potentially attractive but due to the limitation of bandwidth, transmitting all multi-view video in high resolution may not be feasible. Our goal is to propose a new streaming data format that can be adapted to the limited bandwidth and capable of free-viewpoint video streaming using multi-view video plus depth (MVD). Given a requested free-viewpoint, we use the two closest views and corresponding depth maps to perform free-viewpoint video synthesis. We propose a new data format that consists of all views and corresponding depth maps in a lowered resolution, and the two closest views to the requested viewpoint in the high resolution. When the requested viewpoint changes, the two closest viewpoints will change, but one or both of views are transmitted only in the low resolution during the delay time. Therefore, the resolution compensation is required. In this paper, we investigated several cases where one or both of the views are transmitted only in the low resolution. We proposed adequate view synthesis method for multi resolution multi-view video plus depth. Experimental results show that our framework achieves view synthesis quality close to high resolution multi-view video plus depth.

  19. Potential radionuclide emissions from stacks on the Hanford Site, Part 2: Dose assessment methodology using portable low-resolution gamma spectroscoy

    SciTech Connect

    Barnett, J.M.

    1994-07-01

    In September 1992, the Westinghouse Hanford Company began developing an in situ measurement method to assess gamma radiation emanating from high-efficiency particulate air filters using portable low-resolution gamma spectroscopy. The purpose of the new method was to assess radioactive exhaust stack air emissions from empirical data rather than from theoretical models and to determine the potential unabated dose to an offsite theoretical maximally exposed individual. In accordance with Title 40, Code of Federal Regulations, Part 61, Subpart H, ``National Emission Standards for Hazardous Air Pollutants``, stacks that have the potential to emit {ge} 0.1 mrem per year to the maximally exposed individual are considered ``major`` and must meet the continuous monitoring requirements. After the method was tested and verified, the US Environmental Protection Agency, Region 10, approved its use in June 1993. Of the 125 stacks operated by the Westinghouse Hanford Company, 22 were targeted for evaluation by this method; and 15 were assessed. The most significant,result from this study was the redesignation. of the T Plant main stack. The stack was assessed as being ``minor``, and it now only requires periodic confirmatory measurements and meets federally imposed sampling requirements.

  20. Special Education Teachers' Knowledge and Use of Brain-Based Teaching, Common Core State Standards, Formative Feedback Practices and Instructional Efficacy for the Diverse Learning Needs of Students in High and Low Proficiency Groups

    ERIC Educational Resources Information Center

    Walker-Thompson, Malasia

    2014-01-01

    This study examined special education teachers' knowledge and use of: brain-based teaching strategies, Common Core State Standards, formative feedback, and instructional efficacy for diverse students. The study identified the differences amongst special education teachers' responses on the dimensions of brain-based teaching strategies, Common Core…

  1. A model-based approach for detection of objects in low resolution passive-millimeter wave images

    NASA Technical Reports Server (NTRS)

    Tang, Yuan-Liang; Devadiga, Sadashiva; Kasturi, Rangachar; Harris, Randall L., Sr.

    1993-01-01

    We describe a model-based vision system to assist pilots in landing maneuvers under restricted visibility conditions. The system was designed to analyze image sequences obtained from a Passive Millimeter Wave (PMMW) imaging system mounted on the aircraft to delineate runways/taxiways, buildings, and other objects on or near runways. PMMW sensors have good response in a foggy atmosphere; but, their spatial resolution is very low. However, additional data such as airport model and approximate position and orientation of aircraft are available. We exploit these data to guide our model-based system to locate objects in the low resolution image and generate warning signals to alert the pilots. We also derive analytical expressions for the accuracy of the camera position estimate obtained by detecting the position of known objects in the image.

  2. Using Enhanced Sampling and Structural Restraints to Refine Atomic Structures into Low-resolution Electron Microscopy Maps

    PubMed Central

    Vashisth, Harish; Skiniotis, Georgios; Brooks, Charles L.

    2012-01-01

    For a variety of problems in structural biology, low-resolution maps generated by electron microscopy (EM) imaging are often interpreted with the help of various flexible-fitting computational algorithms. In this work, we systematically analyze the quality of final models of various proteins obtained via molecular dynamics flexible fitting (MDFF) by varying the map-resolution, strength of structural restraints, and the steering forces. We find that MDFF can be extended to understand conformational changes in lower-resolution maps if larger structural restraints and lower steering forces are used to prevent overfitting. We further show that the capabilities of MDFF can be extended by combining it with an enhanced conformational sampling method, temperature-accelerated molecular dynamics (TAMD). Specifically, TAMD can be either used to generate better starting configurations for MDFF fitting, or TAMD-assisted MDFF (TAMDFF) can be performed to accelerate conformational search in atomistic simulations. PMID:22958641

  3. Improving identification accuracy on low resolution and poor quality iris images using an artificial neural network-based matching metric

    NASA Astrophysics Data System (ADS)

    Broussard, Randy P.; Ives, Robert W.

    2011-01-01

    The iris is currently believed to be one of the most accurate biometrics for human identification. The majority of fielded iris identification systems use fractional Hamming distance to compare a new feature template to a stored database. Fractional Hamming distance is extremely fast, but mathematically weights all regions of the iris equally. Research has shown that different regions of the iris contain varying levels of discriminatory information when using circular boundary assumptions. This research evaluates four statistical metrics for accuracy improvements on low resolution and poor quality images. Each metric statistically weights iris regions in an attempt to use the iris information in a more intelligent manner. A similarity metric extracted from the output stage of an artificial neural network demonstrated the most promise. Experiments were performed using occluded, subsampled, and motion blurred images from the CASIA, University of Bath, and ICE 2005 databases. The neural network-based metric improved accuracy at nearly every operating point.

  4. Spectral irradiance calibration in the infrared. II - Alpha Tau and the recalibration of the IRAS low resolution spectrometer

    NASA Technical Reports Server (NTRS)

    Cohen, Martin; Walker, Russell G.; Witteborn, Fred C.

    1992-01-01

    A general process for creating complete, continuous, and absolutely calibrated 1-35 micron stellar spectra is described. The method is demonstrated by constructing an absolutely calibrated 1-35 micron spectrum of Alpha Tau and the method is independently validated using new observations. The absolute calibration of the IRAS low resolution spectrometer (LRS) data base is investigated by comparing the observed spectrum of Alpha Tau with that assumed in the original LRS calibration scheme. An analysis of asteroidal LRS spectra results in an independent assessment of the calibration problems with the LRS and provides a natural complement to the effort based on Alpha Tau. A direct comparison of LRS stellar spectra with independently calibrated long-wavelength airborne and ground-based spectra is made.

  5. The coelacanth rostral organ is a unique low-resolution electro-detector that facilitates the feeding strike

    PubMed Central

    Berquist, Rachel M.; Galinsky, Vitaly L.; Kajiura, Stephen M.; Frank, Lawrence R.

    2015-01-01

    The cartilaginous and non-neopterygian bony fishes have an electric sense typically comprised of hundreds or thousands of sensory canals distributed in broad clusters over the head. This morphology facilitates neural encoding of local electric field intensity, orientation, and polarity, used for determining the position of nearby prey. The coelacanth rostral organ electric sense, however, is unique in having only three paired sensory canals with distribution restricted to the dorsal snout, raising questions about its function. To address this, we employed magnetic resonance imaging methods to map electrosensory canal morphology in the extant coelacanth, Latimeria chalumnae, and a simple dipole ‘rabbit ears' antennae model with toroidal gain function to approximate their directional sensitivity. This identified a unique focal region of electrosensitivity directly in front of the mouth, and is the first evidence of a low-resolution electro-detector that solely facilitates prey ingestion. PMID:25758410

  6. Temperature Accelerated Molecular Dynamics with Soft-Ratcheting Criterion Orients Enhanced Sampling by Low-Resolution Information.

    PubMed

    Cortes-Ciriano, Isidro; Bouvier, Guillaume; Nilges, Michael; Maragliano, Luca; Malliavin, Thérèse E

    2015-07-14

    Many proteins exhibit an equilibrium between multiple conformations, some of them being characterized only by low-resolution information. Visiting all conformations is a demanding task for computational techniques performing enhanced but unfocused exploration of collective variable (CV) space. Otherwise, pulling a structure toward a target condition biases the exploration in a way difficult to assess. To address this problem, we introduce here the soft-ratcheting temperature-accelerated molecular dynamics (sr-TAMD), where the exploration of CV space by TAMD is coupled to a soft-ratcheting algorithm that filters the evolving CV values according to a predefined criterion. Any low resolution or even qualitative information can be used to orient the exploration. We validate this technique by exploring the conformational space of the inactive state of the catalytic domain of the adenyl cyclase AC from Bordetella pertussis. The domain AC gets activated by association with calmodulin (CaM), and the available crystal structure shows that in the complex the protein has an elongated shape. High-resolution data are not available for the inactive, CaM-free protein state, but hydrodynamic measurements have shown that the inactive AC displays a more globular conformation. Here, using as CVs several geometric centers, we use sr-TAMD to enhance CV space sampling while filtering for CV values that correspond to centers moving close to each other, and we thus rapidly visit regions of conformational space that correspond to globular structures. The set of conformations sampled using sr-TAMD provides the most extensive description of the inactive state of AC up to now, consistent with available experimental information. PMID:26575778

  7. LORES: Low resolution shape program for the calculation of small angle scattering profiles for biological macromolecules in solution

    NASA Astrophysics Data System (ADS)

    Zhou, J.; Deyhim, A.; Krueger, S.; Gregurick, S. K.

    2005-08-01

    A program for determining the low resolution shape of biological macromolecules, based on the optimization of a small angle neutron scattering profile to experimental data, is presented. This program, termed LORES, relies on a Monte Carlo optimization procedure and will allow for multiple scattering length densities of complex structures. It is therefore more versatile than utilizing a form factor approach to produce low resolution structural models. LORES is easy to compile and use, and allows for structural modeling of biological samples in real time. To illustrate the effectiveness and versatility of the program, we present four specific biological examples, Apoferritin (shell model), Ribonuclease S (ellipsoidal model), a 10-mer dsDNA (duplex helix) and a construct of a 10-mer DNA/PNA duplex helix (heterogeneous structure). These examples are taken from protein and nucleic acid SANS studies, of both large and small scale structures. We find, in general, that our program will accurately reproduce the geometric shape of a given macromolecule, when compared with the known crystallographic structures. We also present results to illustrate the lower limit of the experimental resolution which the LORES program is capable of modeling. Program summaryTitle of program:LORES Catalogue identifier: ADVC Program summary URL:http://cpc.cs.qub.ac.uk/summaries/ADVC Program obtainable from: CPC Program Library, Queen's University of Belfast, N. Ireland Computer:SGI Origin200, SGI Octane, SGI Linux, Intel Pentium PC Operating systems:UNIX64 6.5 and LINUX 2.4.7 Programming language used:C Memory required to execute with typical data:8 MB No. of lines in distributed program, including test data, etc.:2270 No. of bytes in distributed program, including test data, etc.:13 302 Distribution format:tar.gz External subprograms used:The entire code must be linked with the MATH library

  8. Low Resolution Solution Structure of HAMLET and the Importance of Its Alpha-Domains in Tumoricidal Activity

    PubMed Central

    Ho CS, James; Rydstrom, Anna; Manimekalai, Malathy Sony Subramanian; Svanborg, Catharina; Grüber, Gerhard

    2012-01-01

    HAMLET (Human Alpha-lactalbumin Made LEthal to Tumor cells) is the first member in a new family of protein-lipid complexes with broad tumoricidal activity. Elucidating the molecular structure and the domains crucial for HAMLET formation is fundamental for understanding its tumoricidal function. Here we present the low-resolution solution structure of the complex of oleic acid bound HAMLET, derived from small angle X-ray scattering data. HAMLET shows a two-domain conformation with a large globular domain and an extended part of about 2.22 nm in length and 1.29 nm width. The structure has been superimposed into the related crystallographic structure of human ?-lactalbumin, revealing that the major part of ?-lactalbumin accommodates well in the shape of HAMLET. However, the C-terminal residues from L105 to L123 of the crystal structure of the human ?-lactalbumin do not fit well into the HAMLET structure, resulting in an extended conformation in HAMLET, proposed to be required to form the tumoricidal active HAMLET complex with oleic acid. Consistent with this low resolution structure, we identified biologically active peptide epitopes in the globular as well as the extended domains of HAMLET. Peptides covering the alpha1 and alpha2 domains of the protein triggered rapid ion fluxes in the presence of sodium oleate and were internalized by tumor cells, causing rapid and sustained changes in cell morphology. The alpha peptide-oleate bound forms also triggered tumor cell death with comparable efficiency as HAMLET. In addition, shorter peptides corresponding to those domains are biologically active. These findings provide novel insights into the structural prerequisites for the dramatic effects of HAMLET on tumor cells. PMID:23300861

  9. Low resolution solution structure of HAMLET and the importance of its alpha-domains in tumoricidal activity.

    PubMed

    Ho, C S James; Rydstrom, Anna; Manimekalai, Malathy Sony Subramanian; Svanborg, Catharina; Grüber, Gerhard

    2012-01-01

    HAMLET (Human Alpha-lactalbumin Made LEthal to Tumor cells) is the first member in a new family of protein-lipid complexes with broad tumoricidal activity. Elucidating the molecular structure and the domains crucial for HAMLET formation is fundamental for understanding its tumoricidal function. Here we present the low-resolution solution structure of the complex of oleic acid bound HAMLET, derived from small angle X-ray scattering data. HAMLET shows a two-domain conformation with a large globular domain and an extended part of about 2.22 nm in length and 1.29 nm width. The structure has been superimposed into the related crystallographic structure of human ?-lactalbumin, revealing that the major part of ?-lactalbumin accommodates well in the shape of HAMLET. However, the C-terminal residues from L105 to L123 of the crystal structure of the human ?-lactalbumin do not fit well into the HAMLET structure, resulting in an extended conformation in HAMLET, proposed to be required to form the tumoricidal active HAMLET complex with oleic acid. Consistent with this low resolution structure, we identified biologically active peptide epitopes in the globular as well as the extended domains of HAMLET. Peptides covering the alpha1 and alpha2 domains of the protein triggered rapid ion fluxes in the presence of sodium oleate and were internalized by tumor cells, causing rapid and sustained changes in cell morphology. The alpha peptide-oleate bound forms also triggered tumor cell death with comparable efficiency as HAMLET. In addition, shorter peptides corresponding to those domains are biologically active. These findings provide novel insights into the structural prerequisites for the dramatic effects of HAMLET on tumor cells. PMID:23300861

  10. Semi-automated 3D segmentation of major tracts in the rat brain: comparing DTI with standard histological methods.

    PubMed

    Gyengesi, Erika; Calabrese, Evan; Sherrier, Matthew C; Johnson, G Allan; Paxinos, George; Watson, Charles

    2014-03-01

    Researchers working with rodent models of neurological disease often require an accurate map of the anatomical organization of the white matter of the rodent brain. With the increasing popularity of small animal MRI techniques, including diffusion tensor imaging (DTI), there is considerable interest in rapid segmentation methods of neurological structures for quantitative comparisons. DTI-derived tractography allows simple and rapid segmentation of major white matter tracts, but the anatomic accuracy of these computer-generated fibers is open to question and has not been rigorously evaluated in the rat brain. In this study, we examine the anatomic accuracy of tractography-based segmentation in the adult rat brain. We analysed 12 major white matter pathways using semi-automated tractography-based segmentation alongside manual segmentation of Gallyas silver-stained histology sections. We applied four fiber-tracking algorithms to the DTI data-two integration methods and two deflection methods. In many cases, tractography-based segmentation closely matched histology-based segmentation; however different tractography algorithms produced dramatically different results. Results suggest that certain white matter pathways are more amenable to tractography-based segmentation than others. We believe that these data will help researchers decide whether it is appropriate to use tractography-based segmentation of white matter structures for quantitative DTI-based analysis of neurologic disease models. PMID:23455647

  11. Limitations of low resolution mass spectrometry in the electron capture negative ionization mode for the analysis of short- and medium-chain chlorinated paraffins.

    PubMed

    Reth, Margot; Oehme, Michael

    2004-04-01

    The analysis of complex mixtures of chlorinated paraffins (CPs) with short (SCCPs, C(10)-C(13)) and medium (MCCPs, C(14)-C(17)) chain lengths can be disturbed by mass overlap, if low resolution mass spectrometry (LRMS) in the electron capture negative ionization mode is employed. This is caused by CP congeners with the same nominal mass, but with five carbon atoms more and two chlorine atoms less; for example C(11)H(17)(37)Cl(35)Cl(6) ( m/ z 395.9) and C(16)H(29)(35)Cl(5) ( m/ z 396.1). This can lead to an overestimation of congener group quantity and/or of total CP concentration. The magnitude of this interference was studied by evaluating the change after mixing a SCCP standard and a MCCP standard 1+1 (S+MCCP mixture) and comparing it to the single standards. A quantification of the less abundant C(16) and C(17) congeners present in the MCCP standard was not possible due to interference from the major C(11) and C(12) congeners in the SCCPs. Also, signals for SCCPs (C(10)-C(12)) with nine and ten chlorine atoms were mimicked by MCCPs (C(15)-C(17)) with seven and eight chlorine atoms (for instance C(10)H(12)Cl(10) by C(15)H(24)Cl(8)). A similar observation was made for signals from C(15)-C(17) CPs with four and five chlorine atoms resulting from SCCPs (C(10)-C(12)) with six and seven chlorine atoms (such as C(15)H(28)Cl(4) by C(10)H(16)Cl(6)) in the S+MCCP mixture. It could be shown that the quantification of the most abundant congeners (C(11)-C(14)) is not affected by any interference. The determination of C(10) and C(15) congeners is partly disturbed, but this can be detected by investigating isotope ratios, retention time ranges and the shapes of the CP signals. Also, lower chlorinated compounds forming [M+Cl](-) as the most abundant ion instead of [M-Cl](-) are especially sensitive to systematic errors caused by superposition of ions of different composition and the same nominal mass. PMID:14997265

  12. Retrieval of distributed irrigation scenarios with a SVAT model (ICARE) based on high and low resolution thermic data (ASTER, MODIS)

    NASA Astrophysics Data System (ADS)

    Chirouze, J.; Boulet, G.; Jarlan, L.; Rivalland, V.; Garatuza Payan, J.; Watts, C.; Rodriguez, J. C.; Ezzahar, J.; Er-Raki, S.; Chehbouni, G.

    2012-04-01

    In the current context of climatic change, and with the evolution of anthropogenic behaviors, the optimization of water use in irrigated agriculture, particularly in arid and semi-arid regions, has become a main issue in the management of water resources. Based on a mechanistic understanding of the exchanges between the land surface and the atmosphere, Soil-Vegetation-Atmosphere Transfer models (SVAT) simulate water and energy budgets at the soil-vegetation-atmosphere interface. Remote sensing data, especially land surface temperature, gives us distributed information about the water status of the surface. By assimilating this data at high and low resolution into SVAT models, we should be able to estimate with a good accuracy water use scenarios on cultivated zones. In this context, the MISTIGRI mission is developed in order to obtain high resolution thermal data (<100m) with high repetitiveness (daily revisit). In this study, we use a distributed version of the ICARE model (100m resolution), forced with climatic and surface (vegetation and soil water content) data acquired from January to June 2008 on a 4x4km cultivated zone of the Yaqui Valley (Sonora, Mexico). The model has been evaluated at six locations were flux and soil water content measurements were available. The first step of the study is to evaluate the suitability of land surface temperature data in the retrieval of an irrigation scenario, based on synthetic data. The surface temperature outputs of 70 credible scenarios are compared to the original one and eliminated on the basis of a temperature error criterion. Given the good results shown by ICARE in the estimation of the energy fluxes (RMSE < 100 W/m2 for turbulent fluxes) and the soil water content, the results of this study are expected to be quite good. The next step is to use real remote sensing land surface temperature data to do the same open-loop study. The outputs of the 70 credible scenarios are now compared to high (ASTER) and low (MODIS) resolution thermal data. The low revisit rate of high resolution sensors (7 ASTER images in 5 months) and the loss of information due to low resolution of MODIS data are expected to significantly lower the accuracy of the results. Further studies with data assimilation techniques (Particle filtering) are planned in order to improve the retrieval process. Previous studies showed that surface energy balance models like SEBS (Su, 2002) and S-SEBI (Roerink, 2000), used with ASTER surface temperature images, provided a good estimation of the vegetation stress factor. Thus, assimilating other indexes, containing more information on the water status of the surface will be another way to improve our estimations.

  13. LOW-RESOLUTION SPECTROSCOPY FOR THE GLOBULAR CLUSTERS WITH SIGNS OF SUPERNOVA ENRICHMENT: M22, NGC 1851, AND NGC 288

    SciTech Connect

    Lim, Dongwook; Han, Sang-Il; Lee, Young-Wook; Roh, Dong-Goo; Sohn, Young-Jong; Chun, Sang-Hyun; Lee, Jae-Woo; Johnson, Christian I.

    2015-01-01

    There is increasing evidence for the presence of multiple red giant branches (RGBs) in the color-magnitude diagrams of massive globular clusters (GCs). In order to investigate the origin of this split on the RGB, we have performed new narrow-band Ca photometry and low-resolution spectroscopy for M22, NGC 1851, and NGC 288. We find significant differences (more than 4σ) in calcium abundance from the spectroscopic HK' index for M22 and NGC 1851. We also find more than 8σ differences in CN-band strength between the Ca-strong and Ca-weak subpopulations for these GCs. For NGC 288, however, a large difference is detected only in the CN strength. The calcium abundances of RGB stars in this GC are identical to within the errors. This is consistent with the conclusion from our new Ca photometry where the RGB splits are confirmed in M22 and NGC 1851, but not in NGC 288. We also find interesting differences in the CN-CH correlations among these GCs. While CN and CH are anti-correlated in NGC 288, they show a positive correlation in M22. NGC 1851, however, shows no difference in CH between the two groups of stars with different CN strengths. We suggest that all of these systematic differences would be best explained by how strongly Type II supernovae enrichment has contributed to the chemical evolution of these GCs.

  14. Gender classification in low-resolution surveillance video: in-depth comparison of random forests and SVMs

    NASA Astrophysics Data System (ADS)

    Geelen, Christopher D.; Wijnhoven, Rob G. J.; Dubbelman, Gijs; de With, Peter H. N.

    2015-03-01

    This research considers gender classification in surveillance environments, typically involving low-resolution images and a large amount of viewpoint variations and occlusions. Gender classification is inherently difficult due to the large intra-class variation and interclass correlation. We have developed a gender classification system, which is successfully evaluated on two novel datasets, which realistically consider the above conditions, typical for surveillance. The system reaches a mean accuracy of up to 90% and approaches our human baseline of 92.6%, proving a high-quality gender classification system. We also present an in-depth discussion of the fundamental differences between SVM and RF classifiers. We conclude that balancing the degree of randomization in any classifier is required for the highest classification accuracy. For our problem, an RF-SVM hybrid classifier exploiting the combination of HSV and LBP features results in the highest classification accuracy of 89.9 0.2%, while classification computation time is negligible compared to the detection time of pedestrians.

  15. Stars and brown dwarfs in the ? Orionis cluster. III. OSIRIS/GTC low-resolution spectroscopy of variable sources

    NASA Astrophysics Data System (ADS)

    Caballero, J. A.; Cabrera-Lavers, A.; García-Álvarez, D.; Pascual, S.

    2012-10-01

    Context. Although many studies have been performed so far, there are still dozens of low-mass stars and brown dwarfs in the young ? Orionis open cluster without detailed spectroscopic characterisation. Aims: We look for unknown strong accretors and disc hosts that were undetected in previous surveys. Methods: We collected low-resolution spectroscopy (R ~ 700) of ten low-mass stars and brown dwarfs in ? Orionis with OSIRIS at the Gran Telescopio Canarias under very poor weather conditions. These objects display variability in the optical, infrared, H?, and/or X-rays on time scales of hours to years. We complemented our spectra with optical and near-/mid-infrared photometry. Results: For seven targets, we detected lithium in absorption, identified H?, the calcium doublet, and forbidden lines in emission, and/or determined spectral types for the first time. We characterise in detail a faint, T Tauri-like brown dwarf with an 18 h-period variability in the optical and a large H? equivalent width of -125 ± 15 Å, as well as two M1-type, X-ray-flaring, low-mass stars, one with a warm disc and forbidden emission lines, the other with a previously unknown cold disc with a large inner hole. Conclusions: New unrevealed strong accretors and disc hosts, even below the substellar limit, await discovery among the list of known ? Orionis stars and brown dwarfs that are variable in the optical and have no detailed spectroscopic characterisation yet.

  16. Evaluation of trace analyte identification in complex matrices by low-resolution gas chromatography - Mass spectrometry through signal simulation.

    PubMed

    Bettencourt da Silva, Ricardo J N

    2016-04-01

    The identification of trace levels of compounds in complex matrices by conventional low-resolution gas chromatography hyphenated with mass spectrometry is based in the comparison of retention times and abundance ratios of characteristic mass spectrum fragments of analyte peaks from calibrators with sample peaks. Statistically sound criteria for the comparison of these parameters were developed based on the normal distribution of retention times and the simulation of possible non-normal distribution of correlated abundances ratios. The confidence level used to set the statistical maximum and minimum limits of parameters defines the true positive rates of identifications. The false positive rate of identification was estimated from worst-case signal noise models. The estimated true and false positive identifications rate from one retention time and two correlated ratios of three fragments abundances were combined using simple Bayes' statistics to estimate the probability of compound identification being correct designated examination uncertainty. Models of the variation of examination uncertainty with analyte quantity allowed the estimation of the Limit of Examination as the lowest quantity that produced "Extremely strong" evidences of compound presence. User friendly MS-Excel files are made available to allow the easy application of developed approach in routine and research laboratories. The developed approach was successfully applied to the identification of chlorpyrifos-methyl and malathion in QuEChERS method extracts of vegetables with high water content for which the estimated Limit of Examination is 0.14mgkg(-1) and 0.23mgkg(-1) respectively. PMID:26838443

  17. Substrate cleavage pattern, biophysical characterization and low-resolution structure of a novel hyperthermostable arabinanase from Thermotoga petrophila.

    PubMed

    Squina, Fabio M; Santos, Camila R; Ribeiro, Daniela A; Cota, Júnio; de Oliveira, Renata R; Ruller, Roberto; Mort, Andrew; Murakami, Mario T; Prade, Rolf A

    2010-09-01

    Arabinan is a plant structural polysaccharide degraded by two enzymes; alpha-l-arabinofuranosidase and endo-1,5-alpha-l-arabinanase. These enzymes are highly diversified in nature, however, little is known about their biochemical and biophysical properties. We have characterized a novel arabinanase (AbnA) isolated from Thermotoga petrophila with unique thermostable properties such as the insignificant decrease of residual activity after incubation up to 90 degrees C. We determined the AbnA mode of operation through capillary zone electrophoresis, which accumulates arabinotriose and arabinobiose as end products after hydrolysis of arabinan-containing polysaccharides. Spectroscopic analyses by Far-UV circular dichroism and intrinsic tryptophan fluorescence emission demonstrated that AbnA is folded and formed mainly by beta-sheet structural elements. In silico molecular modeling showed that the AbnA structure encompasses a five-bladed beta-propeller catalytic core juxtaposed by distorted up-and-down beta-barrel domain. The low-resolution structure determined by small angle X-ray scattering indicated that AbnA is monomeric in solution and its molecular shape is in full agreement with the model. PMID:20678476

  18. Using selenomethionyl derivatives to assign sequence in low-resolution structures of the AP2 clathrin adaptor.

    PubMed

    Kelly, Bernard T; Graham, Stephen C; Owen, David J

    2016-03-01

    Selenomethionine incorporation is a powerful technique for assigning sequence to regions of electron density at low resolution. Genetic introduction of methionine point mutations and the subsequent preparation and crystallization of selenomethionyl derivatives permits unambiguous sequence assignment by enabling the placement of the anomalous scatterers (Se atoms) thus introduced. Here, the use of this approach in the assignment of sequence in a part of the AP2 clathrin adaptor complex that is responsible for clathrin binding is described. AP2 plays a pivotal role in clathrin-mediated endocytosis, a tightly regulated process in which cell-surface transmembrane proteins are internalized from the plasma membrane by incorporation into lipid-enclosed transport vesicles. AP2 binds cargo destined for internalization and recruits clathrin, a large trimeric protein that helps to deform the membrane to produce the transport vesicle. By selenomethionine labelling of point mutants, it was shown that the clathrin-binding site is buried within a deep cleft of the AP2 complex. A membrane-stimulated conformational change in AP2 releases the clathrin-binding site from autoinhibition, thereby linking clathrin recruitment to membrane localization. PMID:26960121

  19. Using selenomethionyl derivatives to assign sequence in low-resolution structures of the AP2 clathrin adaptor

    PubMed Central

    Kelly, Bernard T.; Graham, Stephen C.; Owen, David J.

    2016-01-01

    Selenomethionine incorporation is a powerful technique for assigning sequence to regions of electron density at low resolution. Genetic introduction of methionine point mutations and the subsequent preparation and crystallization of selenomethionyl derivatives permits unambiguous sequence assignment by enabling the placement of the anomalous scatterers (Se atoms) thus introduced. Here, the use of this approach in the assignment of sequence in a part of the AP2 clathrin adaptor complex that is responsible for clathrin binding is described. AP2 plays a pivotal role in clathrin-mediated endocytosis, a tightly regulated process in which cell-surface transmembrane proteins are internalized from the plasma membrane by incorporation into lipid-enclosed transport vesicles. AP2 binds cargo destined for internalization and recruits clathrin, a large trimeric protein that helps to deform the membrane to produce the transport vesicle. By selenomethionine labelling of point mutants, it was shown that the clathrin-binding site is buried within a deep cleft of the AP2 complex. A membrane-stimulated conformational change in AP2 releases the clathrin-binding site from autoinhibition, thereby linking clathrin recruitment to membrane localization. PMID:26960121

  20. Design of an EEG-based brain-computer interface (BCI) from standard components running in real-time under Windows.

    PubMed

    Guger, C; Schlögl, A; Walterspacher, D; Pfurtscheller, G

    1999-01-01

    An EEG-based brain-computer interface (BCI) is a direct connection between the human brain and the computer. Such a communication system is needed by patients with severe motor impairments (e.g. late stage of Amyotrophic Lateral Sclerosis) and has to operate in real-time. This paper describes the selection of the appropriate components to construct such a BCI and focuses also on the selection of a suitable programming language and operating system. The multichannel system runs under Windows 95, equipped with a real-time Kernel expansion to obtain reasonable real-time operations on a standard PC. Matlab controls the data acquisition and the presentation of the experimental paradigm, while Simulink is used to calculate the recursive least square (RLS) algorithm that describes the current state of the EEG in real-time. First results of the new low-cost BCI show that the accuracy of differentiating imagination of left and right hand movement is around 95%. PMID:10194880

  1. Simulation of ENSO-like phenomena with a low-resolution coupled GCM of the global ocean and atmosphere

    SciTech Connect

    Lau, Ngarcheung; Philander, S.G.H.; Nath, M.J. )

    1992-04-01

    A 140-year simulation of the ocean-atmosphere climate system has been performed by the GFDL Climate Dynamics Project using a low-resolution coupled general circulation model (GCM). The model was subjected to annually averaged insolation throughout the integration. This coupled system exhibits well-defined fluctuations in the tropical Pacific, with a preferred time scale of 3-4 years. The characteristics of these recurrent anomalies were examined by applying an extended empirical orthogonal function (EEOF) analysis to selected model variables. These results indicate that the simulated oscillations are accompanied by coherent changes in the atmospheric and oceanic circulation. The spatial patterns associated with the leading EEOF mode indicate that SST anomalies make their first appearance off the Peru-Ecuador coast and then migrate steadily westward, with an average transit time of 12-15 months. The arrival and eventual decay of SST fluctuations in the western Pacific is typically followed by the initiation of anomalies of the opposite polarity along the American coasts. The space-time evolution of various meteorological and oceanographic signals exhibits well-defined phase relationships with the SST perturbations. Some aspects of the model behavior during these warm and cold episodes are reminiscent of observed phenomena associated with the El Nino-Southern Oscillation (ENSO). Analysis of the climatological heat budget for the top ocean layer indicates a near balance between horizontal and vertical temperature advection by the time-mean flow, vertical diffusion, and heat input from the overlying atmosphere. The principal mechanisms associated with the simulated ENSO-like cycles were then studied by examining the local heat budget for the SST perturbations. The relative importance of various linear advective processes in the heat budget exhibits a notable dependence on geographical location and on the specific phase of the ENSO-like cycle.

  2. B fields in OB stars (BOB): Low-resolution FORS2 spectropolarimetry of the first sample of 50 massive stars

    NASA Astrophysics Data System (ADS)

    Fossati, L.; Castro, N.; Schöller, M.; Hubrig, S.; Langer, N.; Morel, T.; Briquet, M.; Herrero, A.; Przybilla, N.; Sana, H.; Schneider, F. R. N.; de Koter, A.; BOB Collaboration

    2015-10-01

    Within the context of the collaboration "B fields in OB stars" (BOB), we used the FORS2 low-resolution spectropolarimeter to search for a magnetic field in 50 massive stars, including two reference magnetic massive stars. Because of the many controversies of magnetic field detections obtained with the FORS instruments, we derived the magnetic field values with two completely independent reduction and analysis pipelines. We compare and discuss the results obtained from the two pipelines. We obtained a general good agreement, indicating that most of the discrepancies on magnetic field detections reported in the literature are caused by the interpretation of the significance of the results (i.e., 3-4σ detections considered as genuine, or not), instead of by significant differences in the derived magnetic field values. By combining our results with past FORS1 measurements of HD 46328, we improve the estimate of the stellar rotation period, obtaining P = 2.17950 ± 0.00009 days. For HD 125823, our FORS2 measurements do not fit the available magnetic field model, based on magnetic field values obtained 30 years ago. We repeatedly detect a magnetic field for the O9.7V star HD 54879, the HD 164492C massive binary, and the He-rich star CPD -57 3509. We obtain a magnetic field detection rate of 6 ± 4%, while by considering only the apparently slow rotators we derive a detection rate of 8 ± 5%, both comparable with what was previously reported by other similar surveys. We are left with the intriguing result that, although the large majority of magnetic massive stars is rotating slowly, our detection rate is not a strong function of the stellar rotational velocity. Based on observations made with ESO Telescopes at the La Silla Paranal Observatory under programme ID 191.D-0255(A, C).

  3. Basic principles of static proton low-resolution spin diffusion NMR in nanophase-separated materials with mobility contrast.

    PubMed

    Schäler, Kerstin; Roos, Matthias; Micke, Peter; Golitsyn, Yury; Seidlitz, Anne; Thurn-Albrecht, Thomas; Schneider, Horst; Hempel, Günter; Saalwächter, Kay

    2015-11-01

    We review basic principles of low-resolution proton NMR spin diffusion experiments, relying on mobility differences in nm-sized phases of inhomogeneous organic materials such as block-co- or semicrystalline polymers. They are of use for estimates of domain sizes and insights into nanometric dynamic inhomogeneities. Experimental procedures and limitations of mobility-based signal decomposition/filtering prior to spin diffusion are addressed on the example of as yet unpublished data on semicrystalline poly(?-caprolactone), PCL. Specifically, we discuss technical aspects of the quantitative, dead-time free detection of rigid-domain signals by aid of the magic-sandwich echo (MSE), and magic-and-polarization-echo (MAPE) and double-quantum (DQ) magnetization filters to select rigid and mobile components, respectively. Such filters are of general use in reliable fitting approaches for phase composition determinations. Spin diffusion studies at low field using benchtop instruments are challenged by rather short (1)H T1 relaxation times, which calls for simulation-based analyses. Applying these, in combination with domain sizes as determined by small-angle X-ray scattering, we have determined spin diffusion coefficients D for PCL (0.34, 0.19 and 0.032nm(2)/ms for crystalline, interphase and amorphous parts, respectively). We further address thermal-history effects related to secondary crystallization. Finally, the state of knowledge concerning the connection between D values determined locally at the atomic level, using (13)C detection and CP- or REDOR-based "(1)H hole burning" procedures, and those obtained by calibration experiments, is summarized. Specifically, the non-trivial dependence of D on the magic-angle spinning (MAS) frequency, with a minimum under static and a local maximum under moderate-MAS conditions, is highlighted. PMID:26404771

  4. Driving and braking control of PM synchronous motor based on low-resolution hall sensor for battery electric vehicle

    NASA Astrophysics Data System (ADS)

    Gu, Jing; Ouyang, Minggao; Li, Jianqiu; Lu, Dongbin; Fang, Chuan; Ma, Yan

    2013-01-01

    Resolvers are normally employed for rotor positioning in motors for electric vehicles, but resolvers are expensive and vulnerable to vibrations. Hall sensors have the advantages of low cost and high reliability, but the positioning accuracy is low. Motors with Hall sensors are typically controlled by six-step commutation algorithm, which brings high torque ripple. This paper studies the high-performance driving and braking control of the in-wheel permanent magnetic synchronous motor (PMSM) based on low-resolution Hall sensors. Field oriented control (FOC) based on Hall-effect sensors is developed to reduce the torque ripple. The positioning accuracy of the Hall sensors is improved by interpolation between two consecutive Hall signals using the estimated motor speed. The position error from the misalignment of the Hall sensors is compensated by the precise calibration of Hall transition timing. The braking control algorithms based on six-step commutation and FOC are studied. Two variants of the six-step commutation braking control, namely, half-bridge commutation and full-bridge commutation, are discussed and compared, which shows that the full-bridge commutation could better explore the potential of the back electro-motive forces (EMF), thus can deliver higher efficiency and smaller current ripple. The FOC braking is analyzed with the phasor diagrams. At a given motor speed, the motor turns from the regenerative braking mode into the plug braking mode if the braking torque exceeds a certain limit, which is proportional to the motor speed. Tests in the dynamometer show that a smooth control could be realized by FOC driving control and the highest efficiency and the smallest current ripple could be achieved by FOC braking control, compared to six-step commutation braking control. Therefore, FOC braking is selected as the braking control algorithm for electric vehicles. The proposed research ensures a good motor control performance while maintaining low cost and high reliability.

  5. Low-resolution mass spectrometric relative response factors (RRFs) and relative retention times (RRTs) on two common gas chromatographic stationary phases for 87 polychlorinated dibenzofurans.

    PubMed

    Lundgren, Kjell; Rappe, Christoffer; Tysklind, Mats

    2004-05-01

    All 87 tetra- to octa-chlorinated dibenzofurans (PCDFs) were analysed using high-resolution gas chromatography/low-resolution mass spectrometry (HRGC-LRMS). The mass spectrometer was operated in two different modes: electron ionisation (EI), and negative ion chemical ionisation (NCI) with methane as a reagent gas. Baseline separation and identification of all PCDF congeners was carried out using one non-polar (DB-5) and one polar (RT-2330) capillary GC column. Relative retention times (RRTs) on both columns, and relative response factors (RRFs) in both EI- and NCI-modes, were calculated for all 87 of the PCDFs. Comparison of the EI-RRFs and NCI-RRFs showed that the mass spectrometric NCI-responses varied to a higher degree than the EI-responses. The level of NCI-response was dependent on the substitution positions of the chlorine atoms on the dibenzofuran molecule skeleton. The ratio between the highest and lowest RRFs was 26 in the NCI-mode, but only 2.3 in the EI-mode. Thus, quantification of tetra- to octa-CDFs in environmental samples using the NCI-mode will result in incorrect estimates of PCDF concentrations unless 13C-labelled internal standards are used for each congener, or RRFs are taken into consideration. In contrast, the quantification of PCDFs in the EI-mode using a single internal 13C-labelled PCDF standard for each PCDF homologue is accurate according to the findings in this investigation. A flue gas sample from a municipal solid waste incinerator (MSWI) analysed in the NCI-mode was quantified with and without NCI-RRFs. When using NCI-RRFs the reported concentration of SigmaPCDFs in the flue gas sample increased by 40%. Furthermore, TCDF analysis was compared using two mass spectrometers (a VG 12-250 and a Finnigan 4500) operating in EI-mode. These quadrupole instruments performed equally well, giving similar EI-RRFs for the tested compounds. PMID:15051368

  6. A clearer view of the insect brain—combining bleaching with standard whole-mount immunocytochemistry allows confocal imaging of pigment-covered brain areas for 3D reconstruction

    PubMed Central

    Stöckl, Anna L.; Heinze, Stanley

    2015-01-01

    In the study of insect neuroanatomy, three-dimensional (3D) reconstructions of neurons and neuropils have become a standard technique. As images have to be obtained from whole-mount brain preparations, pigmentation on the brain surface poses a serious challenge to imaging. In insects, this is a major problematic in the first visual neuropil of the optic lobe, the lamina, which is obstructed by the pigment of the retina as well as by the pigmented fenestration layer. This has prevented inclusion of this major processing center of the insect visual system into most neuroanatomical brain atlases and hinders imaging of neurons within the lamina by confocal microscopy. It has recently been shown that hydrogen peroxide bleaching is compatible with immunohistochemical labeling in insect brains, and we therefore developed a simple technique for removal of pigments on the surface of insect brains by chemical bleaching. We show that our technique enables imaging of the pigment-obstructed regions of insect brains when combined with standard protocols for both anti-synapsin-labeled as well as neurobiotin-injected samples. This method can be combined with different fixation procedures, as well as different fluorophore excitation wavelengths without negative effects on staining quality. It can therefore serve as an effective addition to most standard histology protocols used in insect neuroanatomy. PMID:26441552

  7. Evaluation of standard magnetic resonance characteristics used to differentiate neoplastic, inflammatory, and vascular brain lesions in dogs.

    PubMed

    Young, Benjamin D; Fosgate, Geoffrey T; Holmes, Shannon P; Wolff, Collin A; Chen-Allen, Annie V; Kent, Marc; Platt, Simon R; Savage, Mason Y; Schatzberg, Scott J; Levine, Jonathan M

    2014-01-01

    Magnetic resonance (MR) imaging characteristics are commonly used to help predict intracranial disease categories in dogs, however, few large studies have objectively evaluated these characteristics. The purpose of this retrospective study was to evaluate MR characteristics that have been used to differentiate neoplastic, inflammatory, and vascular intracranial diseases in a large, multi-institutional population of dogs. Medical records from three veterinary teaching hospitals were searched over a 6-year period for dogs that had diagnostic quality brain MR scans and histologically confirmed intracranial disease. Three examiners who were unaware of histologic diagnosis independently evaluated 19 MR lesion characteristics totaling 57 possible responses. A total of 75 dogs with histologically confirmed intracranial disease were included in analyses: 51 with neoplasia, 18 with inflammatory disease, and six with cerebrovascular disease. Only strong contrast enhancement was more common in neoplasia than other disease categories. A multivariable statistical model suggested that extra-axial origin, T2-FLAIR mixed intensity, and defined lesion margins were also predictive of neoplasia. Meningeal enhancement, irregular lesion shape, and multifocal location distinguished inflammatory diseases from the other disease categories. No MR characteristics distinguished vascular lesions and these appeared most similar to neoplasia. These results differed from a previous report describing seven MR characteristics that were predictive of neoplasia in dogs and cats. Findings from the current study indicated that the high performance of MR for diagnosing canine intracranial diseases might be due to evaluator recognition of combinations of MR characteristics vs. relying on any one MR characteristic alone. PMID:24467341

  8. The relationship between brain cortical activity and brain oxygenation in the prefrontal cortex during hypergravity exposure.

    PubMed

    Smith, Craig; Goswami, Nandu; Robinson, Ryan; von der Wiesche, Melanie; Schneider, Stefan

    2013-04-01

    Artificial gravity has been proposed as a method to counteract the physiological deconditioning of long-duration spaceflight; however, the effects of hypergravity on the central nervous system has had little study. The study aims to investigate whether there is a relationship between prefrontal cortex brain activity and prefrontal cortex oxygenation during exposure to hypergravity. Twelve healthy participants were selected to undergo hypergravity exposure aboard a short-arm human centrifuge. Participants were exposed to hypergravity in the +Gz axis, starting from 0.6 +Gz for women, and 0.8 +Gz for men, and gradually increasing by 0.1 +Gz until the participant showed signs of syncope. Brain cortical activity was measured using electroencephalography (EEG) and localized to the prefrontal cortex using standard low-resolution brain electromagnetic tomography (LORETA). Prefrontal cortex oxygenation was measured using near-infrared spectroscopy (NIRS). A significant increase in prefrontal cortex activity (P < 0.05) was observed during hypergravity exposure compared with baseline. Prefrontal cortex oxygenation was significantly decreased during hypergravity exposure, with a decrease in oxyhemoglobin levels (P < 0.05) compared with baseline and an increase in deoxyhemoglobin levels (P < 0.05) with increasing +Gz level. No significant correlation was found between prefrontal cortex activity and oxy-/deoxyhemoglobin. It is concluded that the increase in prefrontal cortex activity observed during hypergravity was most likely not the result of increased +Gz values resulting in a decreased oxygenation produced through hypergravity exposure. No significant relationship between prefrontal cortex activity and oxygenation measured by NIRS concludes that brain activity during exposure to hypergravity may be difficult to measure using NIRS. Instead, the increase in prefrontal cortex activity might be attributable to psychological stress, which could pose a problem for the use of a short-arm human centrifuge as a countermeasure. PMID:23372141

  9. A Robust Algorithm for Thickness Computation at Low Resolution and Its Application to In Vivo Trabecular Bone CT Imaging

    PubMed Central

    Liu, Yinxiao; Jin, Dakai; Li, Cheng; Janz, Kathleen F.; Burns, Trudy L.; Torner, James C.; Levy, Steven M.; Saha, Punam K.

    2015-01-01

    Adult bone diseases, especially osteoporosis, lead to increased risk of fracture which in turn is associated with substantial morbidity, mortality, and financial costs. Clinically, osteoporosis is defined by low bone mineral density; however, increasing evidence suggests that the microarchitectural quality of trabecular bone (TB) is an important determinant of bone strength and fracture risk. Accurate measures of TB thickness and marrow spacing is of significant interest for early diagnosis of osteoporosis or treatment effects. Here, we present a new robust algorithm for computing TB thickness and marrow spacing at a low resolution achievable in vivo. The method uses a star-line tracing technique that effectively deals with partial voluming effects of in vivo imaging with voxel size comparable to TB thickness. Also, the method avoids the problem of digitization associated with conventional algorithms based on sampling distance transform along skeletons. Accuracy of the method was examined using computer-generated phantom images, while the robustness of the method was evaluated on human ankle specimens in terms of stability across a wide range of voxel sizes, repeat scan reproducibility under in vivo conditions, and correlation between thickness values computed at ex vivo and in vivo imaging resolutions. Also, the sensitivity of the method was examined by evaluating its ability to predict the bone strength of cadaveric specimens. Finally, the method was evaluated in a human study involving 40 healthy young-adult volunteers (age: 19–21 years; 20 males and 20 females) and ten athletes (age: 19–21 years; six males and four females). Across a wide range of voxel sizes, the new method is significantly more accurate and robust as compared to conventional methods. Both TB thickness and marrow spacing measures computed using the new method demonstrated strong associations (R2 ? [0.83, 0.87]) with bone strength. Also, the TB thickness and marrow spacing measures allowed discrimination between male and female volunteers (p ? [0.01, 0.04]) as well as between athletes and nonathletes (p ? [0.005, 0.03]). PMID:24686226

  10. A robust algorithm for thickness computation at low resolution and its application to in vivo trabecular bone CT imaging.

    PubMed

    Liu, Yinxiao; Jin, Dakai; Li, Cheng; Janz, Kathleen F; Burns, Trudy L; Torner, James C; Levy, Steven M; Saha, Punam K

    2014-07-01

    Adult bone diseases, especially osteoporosis, lead to increased risk of fracture which in turn is associated with substantial morbidity, mortality, and financial costs. Clinically, osteoporosis is defined by low bone mineral density; however, increasing evidence suggests that the microarchitectural quality of trabecular bone (TB) is an important determinant of bone strength and fracture risk. Accurate measures of TB thickness and marrow spacing is of significant interest for early diagnosis of osteoporosis or treatment effects. Here, we present a new robust algorithm for computing TB thickness and marrow spacing at a low resolution achievable in vivo. The method uses a star-line tracing technique that effectively deals with partial voluming effects of in vivo imaging with voxel size comparable to TB thickness. Also, the method avoids the problem of digitization associated with conventional algorithms based on sampling distance transform along skeletons. Accuracy of the method was examined using computer-generated phantom images, while the robustness of the method was evaluated on human ankle specimens in terms of stability across a wide range of voxel sizes, repeat scan reproducibility under in vivo conditions, and correlation between thickness values computed at ex vivo and in vivo imaging resolutions. Also, the sensitivity of the method was examined by evaluating its ability to predict the bone strength of cadaveric specimens. Finally, the method was evaluated in a human study involving 40 healthy young-adult volunteers (age: 19-21 years; 20 males and 20 females) and ten athletes (age: 19-21 years; six males and four females). Across a wide range of voxel sizes, the new method is significantly more accurate and robust as compared to conventional methods. Both TB thickness and marrow spacing measures computed using the new method demonstrated strong associations (R2 ? [0.83, 0.87]) with bone strength. Also, the TB thickness and marrow spacing measures allowed discrimination between male and female volunteers (p ? [0.01, 0.04]) as well as between athletes and nonathletes (p ? [0.005, 0.03]). PMID:24686226

  11. Spitzer/infrared spectrograph investigation of mipsgal 24 μm compact bubbles: low-resolution observations

    SciTech Connect

    Nowak, M.; Flagey, N.; Noriega-Crespo, A.; Carey, S. J.; Van Dyk, S. D.; Billot, N.; Paladini, R.

    2014-12-01

    We present Spitzer/InfraRed Spectrograph (IRS) low-resolution observations of 11 compact circumstellar bubbles from the MIPSGAL 24 μm Galactic plane survey. We find that this set of MIPSGAL bubbles (MBs) is divided into two categories and that this distinction correlates with the morphologies of the MBs in the mid-infrared (IR). The four MBs with central sources in the mid-IR exhibit dust-rich, low-excitation spectra, and their 24 μm emission is accounted for by the dust continuum. The seven MBs without central sources in the mid-IR have spectra dominated by high-excitation gas lines (e.g., [O IV] 26.0 μm, [Ne V] 14.3 and 24.3 μm, and [Ne III] 15.5 μm), and the [O IV] line accounts for 50% to almost 100% of the 24 μm emission in five of them. In the dust-poor MBs, the [Ne V] and [Ne III] line ratios correspond to high-excitation conditions. Based on comparisons with published IRS spectra, we suggest that the dust-poor MBs are highly excited planetary nebulae (PNs) with peculiar white dwarfs (e.g., Wolf-Rayet [WR] and novae) at their centers. The central stars of the four dust-rich MBs are all massive star candidates. Dust temperatures range from 40 to 100 K in the outer shells. We constrain the extinction along the lines of sight from the IRS spectra. We then derive distance, dust masses, and dust production rate estimates for these objects. These estimates are all consistent with the nature of the central stars. We summarize the identifications of MBs made to date and discuss the correlation between their mid-IR morphologies and natures. Candidate Be/B[e]/luminous blue variable and WR stars are mainly 'rings' with mid-IR central sources, whereas PNs are mostly 'disks' without mid-IR central sources. Therefore we expect that most of the 300 remaining unidentified MBs will be classified as PNs.

  12. CARMENES science preparation: characterisation of M dwarfs with low-resolution spectroscopy and search for low-mass wide companions to young stars

    NASA Astrophysics Data System (ADS)

    Alonso-Floriano, F. J.

    2015-11-01

    This thesis is focused on the study of low-mass objects that can be targets of exoplanet searches with near-infrared spectrographs in general and CARMENES (Calar Alto high-Resolution search for M dwarfs with Exo-earths with Near-infrared and optical Echelle Spectrographs; see Quirrenbach et al. 2014) in particular. The CARMENES consortium comprises 11 institutions from Germany and Spain that are building a high-resolution spectrograph (R=82,000) with two channels, visible (0.55 - 1.05 um) and infrared (0.95 - 1.7 um), for the 3.5 m Calar Alto telescope. It will observe a sample of 300 M dwarfs in 600 nights of guaranteed time during at least three years, starting in January 2016. The final sample will be chosen from the 2200 M dwarfs included in the CARMENCITA input catalogue. For these stars, we have obtained and collected a large amount of data: spectral types, radial and rotational velocities, photometry in several bands, etc. Part of the e effort of the science preparation necessary for the final selection of targets for CARMENES and other near-infrared spectrographs has been collected in two publications, which are presented in this PhD thesis. In the first publication (Alonso-Floriano et al., 2015A&A...577A.128A), we obtained low-resolution spectra for 753 stars using the CAFOS spectrograph at the 2.2 m Calar Alto telescope. The main goal was to derive accurate spectral types, which are fundamental parameters for the sample selection. We used a grid of 49 standard stars, from spectral types K3V to M8V, together with a double least-square minimisation technique and 31 spectral indices previously defined by other authors. In addition, we quantified the surface gravity, metallicity and chromospheric activity of the sample, in order to detect low-gravity stars (giants and very young), metal-poor and very metal-poor stars (subdwarfs), and very active stars. In the second publication (Alonso-Floriano et al., 2015A&A...583A..85A), we searched for common proper motion companions, especially of low mass, to members of the near young beta Pictoris moving group. First, we compiled a list of 185 members and candidate members to beta Pictoris from 35 representatives studies on this moving group. Next, we used the Aladin and STILTS virtual observatory tools, as well as the PPMXL proper motion and Washington double stars catalogues. The objects that showed similar proper motions to those stars of the sample were targets of an astro-photometric follow-up. The 36 common proper motion companion eventually obtained were subjects of a study of binding energies to determine their physical ligation.

  13. The low-resolution structure of nHDL reconstituted with DMPC with and without cholesterol reveals a mechanism for particle expansion[S

    PubMed Central

    Gogonea, Valentin; Gerstenecker, Gary S.; Wu, Zhiping; Lee, Xavier; Topbas, Celalettin; Wagner, Matthew A.; Tallant, Thomas C.; Smith, Jonathan D.; Callow, Philip; Pipich, Vitaliy; Malet, Hélène; Schoehn, Guy; DiDonato, Joseph A.; Hazen, Stanley L.

    2013-01-01

    Small-angle neutron scattering (SANS) with contrast variation was used to obtain the low-resolution structure of nascent HDL (nHDL) reconstituted with dimyristoyl phosphatidylcholine (DMPC) in the absence and presence of cholesterol, [apoA1:DMPC (1:80, mol:mol) and apoA1:DMPC:cholesterol (1:86:9, mol:mol:mol)]. The overall shape of both particles is discoidal with the low-resolution structure of apoA1 visualized as an open, contorted, and out of plane conformation with three arms in nascent HDL/dimyristoyl phosphatidylcholine without cholesterol (nHDLDMPC) and two arms in nascent HDL/dimyristoyl phosphatidylcholine with cholesterol (nHDLDMPC+Chol). The low-resolution shape of the lipid phase in both nHDLDMPC and nHDLDMPC+Chol were oblate ellipsoids, and fit well within their respective protein shapes. Modeling studies indicate that apoA1 is folded onto itself in nHDLDMPC, making a large hairpin, which was also confirmed independently by both cross-linking mass spectrometry and hydrogen-deuterium exchange (HDX) mass spectrometry analyses. In nHDLDMPC+Chol, the lipid was expanded and no hairpin was visible. Importantly, despite the overall discoidal shape of the whole particle in both nHDLDMPC and nHDLDMPC+Chol, an open conformation (i.e., not a closed belt) of apoA1 is observed. Collectively, these data show that full length apoA1 retains an open architecture that is dictated by its lipid cargo. The lipid is likely predominantly organized as a bilayer with a micelle domain between the open apoA1 arms. The apoA1 configuration observed suggests a mechanism for accommodating changing lipid cargo by quantized expansion of hairpin structures. PMID:23349207

  14. Effects of caffeine and maltodextrin mouth rinsing on P300, brain imaging, and cognitive performance.

    PubMed

    De Pauw, K; Roelands, B; Knaepen, K; Polfliet, M; Stiens, J; Meeusen, R

    2015-03-15

    Caffeine (CAF) and maltodextrin (MALT) mouth rinses (MR) improve exercise performance. The current experiment aims to determine the effect of CAF and MALT MR on cognitive performance and brain activity. Ten healthy male subjects (age 27 ± 3 yr) completed three experimental trials. Each trial included four Stroop tasks: two familiarization tasks, and one task before and one task after an MR period. The reaction time (in milliseconds) and accuracy (percent) of simple, congruent, and incongruent stimuli were assessed. Electroencephalography was applied throughout the experiment to record brain activity. The amplitudes and latencies of the P300 were determined during the Stroop tasks before and after the MR period. Subjects received MR with CAF (0.3 g/25 ml), MALT (1.6 g/25 ml), or placebo (PLAC) in a randomized, double-blind, crossover design. During MR, the brain imaging technique standardized low-resolution brain electromagnetic tomography was applied. Magnitude-based inferences showed that CAF MR is likely trivial (63.5%) and likely beneficial (36.4%) compared with PLAC MR, and compared with MALT MR likely beneficial to reaction time on incongruent stimuli (61.6%). Additionally, both the orbitofrontal and dorsolateral prefrontal cortex were activated only during CAF MR, potentially explaining the likely beneficial effect on reaction times. MALT MR increased brain activity only within the orbitofrontal cortex. However, this brain activation did not alter the reaction time. Furthermore, no significant differences in the accuracy of stimuli responses were observed between conditions. In conclusion, only CAF MR exerted a likely beneficial effect on reaction time due to the subsequent activation of both the orbitofrontal and dorsolateral prefrontal cortexes. PMID:25614603

  15. Vocal and visual stimulation, congruence and lateralization affect brain oscillations in interspecies emotional positive and negative interactions.

    PubMed

    Balconi, Michela; Vanutelli, Maria Elide

    2016-06-01

    The present research explored the effect of cross-modal integration of emotional cues (auditory and visual (AV)) compared with only visual (V) emotional cues in observing interspecies interactions. The brain activity was monitored when subjects processed AV and V situations, which represented an emotional (positive or negative), interspecies (human-animal) interaction. Congruence (emotionally congruous or incongruous visual and auditory patterns) was also modulated. electroencephalography brain oscillations (from delta to beta) were analyzed and the cortical source localization (by standardized Low Resolution Brain Electromagnetic Tomography) was applied to the data. Frequency band (mainly low-frequency delta and theta) showed a significant brain activity increasing in response to negative compared to positive interactions within the right hemisphere. Moreover, differences were found based on stimulation type, with an increased effect for AV compared with V. Finally, delta band supported a lateralized right dorsolateral prefrontal cortex (DLPFC) activity in response to negative and incongruous interspecies interactions, mainly for AV. The contribution of cross-modality, congruence (incongruous patterns), and lateralization (right DLPFC) in response to interspecies emotional interactions was discussed at light of a "negative lateralized effect." PMID:26256040

  16. On the linearity of the SWP camera of the international ultraviolet explorer /IUE/ - A correction algorithm. [for Short Wavelength Prime low resolution spectral images

    NASA Technical Reports Server (NTRS)

    Holm, A.; Schiffer, F. H.; Bohlin, R. C.; Cassatella, A.; Ponz, D. P.

    1982-01-01

    An algorithm is presented for correcting IUE low resolution spectral images obtained with the SWP camera for some of the non-linearity effects reported by Bohlin et al. (1980). The non-linearity problem, which affects SWP images processed at Goddard Space Flight Center in the period May 22, 1978 to July 7, 1979 and at VILSPA in the period June 14, 1978 to August 6, 1979, was essentially due to the use of an Intensity Transfer Function (ITF) that erroneously included a blank image in the 20 percent exposure level. The correction algorithm described here was adopted by the three IUE Agencies in November 1979 as being suitable for most IUE users. It has the advantages to be applicable to any kind of low resolution SWP spectra, to introduce errors which are usually less than the intrinsic photometric errors, and to be of simple application. The results obtained by applying the method to a representative set of spectra of both point and extended sources are reported. In addition, a new evaluation of linearity and reproducibility of the SWP spectral data is provided, based on the improved ITF.

  17. IMPROVING THE ACCURACY OF HISTORIC SATELLITE IMAGE CLASSIFICATION BY COMBINING LOW-RESOLUTION MULTISPECTRAL DATA WITH HIGH-RESOLUTION PANCHROMATIC DATA

    SciTech Connect

    Getman, Daniel J

    2008-01-01

    Many attempts to observe changes in terrestrial systems over time would be significantly enhanced if it were possible to improve the accuracy of classifications of low-resolution historic satellite data. In an effort to examine improving the accuracy of historic satellite image classification by combining satellite and air photo data, two experiments were undertaken in which low-resolution multispectral data and high-resolution panchromatic data were combined and then classified using the ECHO spectral-spatial image classification algorithm and the Maximum Likelihood technique. The multispectral data consisted of 6 multispectral channels (30-meter pixel resolution) from Landsat 7. These data were augmented with panchromatic data (15m pixel resolution) from Landsat 7 in the first experiment, and with a mosaic of digital aerial photography (1m pixel resolution) in the second. The addition of the Landsat 7 panchromatic data provided a significant improvement in the accuracy of classifications made using the ECHO algorithm. Although the inclusion of aerial photography provided an improvement in accuracy, this improvement was only statistically significant at a 40-60% level. These results suggest that once error levels associated with combining aerial photography and multispectral satellite data are reduced, this approach has the potential to significantly enhance the precision and accuracy of classifications made using historic remotely sensed data, as a way to extend the time range of efforts to track temporal changes in terrestrial systems.

  18. Attachment style dimensions are associated with brain activity in response to gaze interaction.

    PubMed

    Cecchini, Marco; Iannoni, Maria Elena; Pandolfo, Anna Lucia; Aceto, Paola; Lai, Carlo

    2015-01-01

    Aim of the present study was to investigate the time course of brain processes involved in the visual perception of different gaze interactions in woman-child dyads and the association between attachment dimensions and brain activation during the presentation of gaze interactions. The hypothesis was that the woman avoidance will produce a greater activation of primary somatosensory and limbic areas. The attachment styles dimensions avoidant-related will be associated with fronto-limbic brain intensity during the convergence of gaze. Electroencephalogram (EEG) data were recorded using a 256-channel HydroCel Geodesic Sensor Net in 44 female subjects (age: 24 ± 2 years). Event-related potential (ERP) components and standardized low-resolution electromagnetic tomography (sLORETA) were analyzed. Participants were administered the attachment style questionnaire before EEG task. A lower P350 latency was found in the fronto-central montage in response to woman avoidance. sLORETA analysis showed a greater intensity of limbic and primary somatosensory areas in response to woman avoidance compared to the others gaze interactions. In response to convergence gaze, the confidence attachment dimension was negatively correlated with the intensities of the right temporal and limbic areas, and the relationships as secondary attachment dimension were positively correlated with the intensities of the bilateral frontal areas and of the left parietal area. PMID:25568957

  19. Brain herniation

    MedlinePLUS

    ... herniation; Uncal herniation; Subfalcine herniation; Tonsillar herniation; Herniation - brain ... Brain herniation occurs when something inside the skull produces pressure that moves brain tissues. This is most ...

  20. Recommendations for Development of New Standardized Forms of Cocoa Breeds and Cocoa Extract Processing for the Prevention of Alzheimer's Disease: Role of Cocoa in Promotion of Cognitive Resilience and Healthy Brain Aging.

    PubMed

    Dubner, Lauren; Wang, Jun; Ho, Lap; Ward, Libby; Pasinetti, Giulio M

    2015-10-27

    It is currently thought that the lackluster performance of translational paradigms in the prevention of age-related cognitive deteriorative disorders, such as Alzheimer's disease (AD), may be due to the inadequacy of the prevailing approach of targeting only a single mechanism. Age-related cognitive deterioration and certain neurodegenerative disorders, including AD, are characterized by complex relationships between interrelated biological phenotypes. Thus, alternative strategies that simultaneously target multiple underlying mechanisms may represent a more effective approach to prevention, which is a strategic priority of the National Alzheimer's Project Act and the National Institute on Aging. In this review article, we discuss recent strategies designed to clarify the mechanisms by which certain brain-bioavailable, bioactive polyphenols, in particular, flavan-3-ols also known as flavanols, which are highly represented in cocoa extracts, may beneficially influence cognitive deterioration, such as in AD, while promoting healthy brain aging. However, we note that key issues to improve consistency and reproducibility in the development of cocoa extracts as a potential future therapeutic agent requires a better understanding of the cocoa extract sources, their processing, and more standardized testing including brain bioavailability of bioactive metabolites and brain target engagement studies. The ultimate goal of this review is to provide recommendations for future developments of cocoa extracts as a therapeutic agent in AD. PMID:26402120

  1. Brain tumours at 7T MRI compared to 3T—contrast effect after half and full standard contrast agent dose: initial results

    PubMed Central

    Noebauer-Huhmann, Iris-Melanie; Szomolanyi, P.; Kronnerwetter, C.; Widhalm, G.; Weber, M.; Nemec, S.; Juras, V.; Ladd, M. E.; Prayer, D.; Trattnig, S.

    2015-01-01

    Objectives To compare the contrast agent effect of a full dose and half the dose of gadobenate dimeglumine in brain tumours at 7 Tesla (7T) MR versus 3 Tesla (3T). Methods Ten patients with primary brain tumours or metastases were examined. Signal intensities were assessed in the lesion and normal brain. Tumour-to-brain contrast and lesion enhancement were calculated. Additionally, two independent readers subjectively graded the image quality and artefacts. Results The enhanced mean tumour-to-brain contrast and lesion enhancement were significantly higher at 7T than at 3T for both half the dose (91.8±45.8 vs. 43.9±25.3 [p=0.010], 128.1±53.7 vs. 75.5±32.4 [p=0.004]) and the full dose (129.2±50.9 vs. 66.6±33.1 [p=0.002], 165.4±54.2 vs. 102.6±45.4 [p=0.004]). Differences between dosages at each field strength were also significant. Lesion enhancement was higher with half the dose at 7T than with the full dose at 3T (p=.037), while the tumour-to-brain contrast was not significantly different. Subjectively, contrast enhancement, visibility, and lesion delineation were better at 7T and with the full dose. All parameters were rated as good, at the least. Conclusion Half the routine contrast agent dose at 7T provided higher lesion enhancement than the full dose at 3T which indicates the possibility of dose reduction at 7T. PMID:25194707

  2. Crystallographic study of a MATE transporter presents a difficult case in structure determination with low-resolution, anisotropic data and crystal twinning.

    PubMed

    Symersky, Jindrich; Guo, Yi; Wang, Jimin; Lu, Min

    2015-11-01

    NorM from Neisseria gonorrhoeae (NorM-NG) belongs to the multidrug and toxic compound extrusion (MATE) family of membrane-transport proteins, which can extrude cytotoxic chemicals across cell membranes and confer multidrug resistance. Here, the structure determination of NorM-NG is described, which had been hampered by low resolution (? 4 Å), data anisotropy and pseudo-merohedral twinning. The crystal structure was solved using molecular replacement and was corroborated by conducting a difference Fourier analysis. The NorM-NG structure displays an extracellular-facing conformation, similar to that of NorM-NG bound to a crystallization chaperone. The approaches taken to determine the NorM-NG structure and the lessons learned from this study are discussed, which may be useful for analyzing X-ray diffraction data with similar shortcomings. PMID:26527145

  3. Mode of operation and low-resolution structure of a multi-domain and hyperthermophilic endo-?-1,3-glucanase from Thermotoga petrophila.

    PubMed

    Cota, Junio; Alvarez, Thabata M; Citadini, Ana P; Santos, Camila Ramos; de Oliveira Neto, Mario; Oliveira, Renata R; Pastore, Glaucia M; Ruller, Roberto; Prade, Rolf A; Murakami, Mario T; Squina, Fabio M

    2011-03-25

    1,3-?-Glucan depolymerizing enzymes have considerable biotechnological applications including biofuel production, feedstock-chemicals and pharmaceuticals. Here we describe a comprehensive functional characterization and low-resolution structure of a hyperthermophilic laminarinase from Thermotoga petrophila (TpLam). We determine TpLam enzymatic mode of operation, which specifically cleaves internal ?-1,3-glucosidic bonds. The enzyme most frequently attacks the bond between the 3rd and 4th residue from the non-reducing end, producing glucose, laminaribiose and laminaritriose as major products. Far-UV circular dichroism demonstrates that TpLam is formed mainly by beta structural elements, and the secondary structure is maintained after incubation at 90°C. The structure resolved by small angle X-ray scattering, reveals a multi-domain structural architecture of a V-shape envelope with a catalytic domain flanked by two carbohydrate-binding modules. PMID:21352806

  4. Crystal structure of a novel non-Pfam protein PF2046 solved using low resolution B-factor sharpening and multi-crystal averaging methods

    SciTech Connect

    Su, Jing; Li, Yang; Shaw, Neil; Zhou, Weihong; Zhang, Min; Xu, Hao; Wang, Bi-Cheng; Liu, Zhi-Jie

    2012-11-13

    Sometimes crystals cannot diffract X-rays beyond 3.0 {angstrom} resolution due to the intrinsic flexibility associated with the protein. Low resolution diffraction data not only pose a challenge to structure determination, but also hamper interpretation of mechanistic details. Crystals of a 25.6 kDa non-Pfam, hypothetical protein, PF2046, diffracted X-rays to 3.38 {angstrom} resolution. A combination of Se-Met derived heavy atom positions with multiple cycles of B-factor sharpening, multi-crystal averaging, restrained refinement followed by manual inspection of electron density and model building resulted in a final model with a R value of 23.5 (R{sub free} = 24.7). The asymmetric unit was large and consisted of six molecules arranged as a homodimer of trimers. Analysis of the structure revealed the presence of a RNA binding domain suggesting a role for PF2046 in the processing of nucleic acids.

  5. Brain mapping after prolonged cycling and during recovery in the heat.

    PubMed

    De Pauw, Kevin; Roelands, Bart; Marusic, Uros; Tellez, Helio Fernandez; Knaepen, Kristel; Meeusen, Romain

    2013-11-01

    The aim of this study was to determine the effect of prolonged intensive cycling and postexercise recovery in the heat on brain sources of altered brain oscillations. After a max test and familiarization trial, nine trained male subjects (23 ± 3 yr; maximal oxygen uptake = 62.1 ± 5.3 ml·min(-1)·kg(-1)) performed three experimental trials in the heat (30°C; relative humidity 43.7 ± 5.6%). Each trial consisted of two exercise tasks separated by 1 h. The first was a 60-min constant-load trial, followed by a 30-min simulated time trial (TT1). The second comprised a 12-min simulated time trial (TT2). After TT1, active recovery (AR), passive rest (PR), or cold water immersion (CWI) was applied for 15 min. Electroencephalography was measured at baseline and during postexercise recovery. Standardized low-resolution brain electromagnetic tomography was applied to accurately pinpoint and localize altered electrical neuronal activity. After CWI, PR and AR subjects completed TT2 in 761 ± 42, 791 ± 76, and 794 ± 62 s, respectively. A prolonged intensive cycling performance in the heat decreased ? activity across the whole brain. Postexercise AR and PR elicited no significant electrocortical differences, whereas CWI induced significantly increased ?3 activity in Brodmann areas (BA) 13 (posterior margin of insular cortex) and BA 40 (supramarginal gyrus). Self-paced prolonged exercise in the heat seems to decrease ? activity, hence representing decreased arousal. Postexercise CWI increased ?3 activity at BA 13 and 40, brain areas involved in somatosensory information processing. PMID:23990240

  6. David Ferrier: brain drawings and brain maps.

    PubMed

    Lazar, J Wayne

    2013-01-01

    This chapter has two emphases, one is about the men who influenced the visual representations that David Ferrier (1843-1928) used to illustrate his work on localization of brain functions during the years 1873-1875, namely, Alexander Ecker, John C. Galton, and Ernest Waterlow, and the other is about the nature of medical representations and of Ferrier's illustrations in particular. Medical illustrations are characterized either as pictures, line drawings, or brain maps. Ferrier's illustrations will be shown to be increasingly sophisticated brain maps that contrast with early nineteenth-century standards of medical illustrations, as exemplified by John Bell (1763-1829). PMID:24041278

  7. A standardized and reproducible protocol for serum-free monolayer culturing of primary paediatric brain tumours to be utilized for therapeutic assays

    PubMed Central

    Sandén, Emma; Eberstål, Sofia; Visse, Edward; Siesjö, Peter; Darabi, Anna

    2015-01-01

    In vitro cultured brain tumour cells are indispensable tools for drug screening and therapeutic development. Serum-free culture conditions tentatively preserve the features of the original tumour, but commonly comprise neurosphere propagation, which is a technically challenging procedure. Here, we define a simple, non-expensive and reproducible serum-free cell culture protocol for establishment and propagation of primary paediatric brain tumour cultures as adherent monolayers. The success rates for establishment of primary cultures (including medulloblastomas, atypical rhabdoid tumour, ependymomas and astrocytomas) were 65% (11/17) and 78% (14/18) for sphere cultures and monolayers respectively. Monolayer culturing was particularly feasible for less aggressive tumour subsets, where neurosphere cultures could not be generated. We show by immunofluorescent labelling that monolayers display phenotypic similarities with corresponding sphere cultures and primary tumours, and secrete clinically relevant inflammatory factors, including PGE2, VEGF, IL-6, IL-8 and IL-15. Moreover, secretion of PGE2 was considerably reduced by treatment with the COX-2 inhibitor Valdecoxib, demonstrating the functional utility of our newly established monolayer for preclinical therapeutic assays. Our findings suggest that this culture method could increase the availability and comparability of clinically representative in vitro models of paediatric brain tumours, and encourages further molecular evaluation of serum-free monolayer cultures. PMID:26183281

  8. A Standardized Method for the Construction of Tracer Specific PET and SPECT Rat Brain Templates: Validation and Implementation of a Toolbox

    PubMed Central

    Vállez Garcia, David; Casteels, Cindy; Schwarz, Adam J.; Dierckx, Rudi A. J. O.; Koole, Michel; Doorduin, Janine

    2015-01-01

    High-resolution anatomical image data in preclinical brain PET and SPECT studies is often not available, and inter-modality spatial normalization to an MRI brain template is frequently performed. However, this procedure can be challenging for tracers where substantial anatomical structures present limited tracer uptake. Therefore, we constructed and validated strain- and tracer-specific rat brain templates in Paxinos space to allow intra-modal registration. PET [18F]FDG, [11C]flumazenil, [11C]MeDAS, [11C]PK11195 and [11C]raclopride, and SPECT [99mTc]HMPAO brain scans were acquired from healthy male rats. Tracer-specific templates were constructed by averaging the scans, and by spatial normalization to a widely used MRI-based template. The added value of tracer-specific templates was evaluated by quantification of the residual error between original and realigned voxels after random misalignments of the data set. Additionally, the impact of strain differences, disease uptake patterns (focal and diffuse lesion), and the effect of image and template size on the registration errors were explored. Mean registration errors were 0.70±0.32mm for [18F]FDG (n = 25), 0.23±0.10mm for [11C]flumazenil (n = 13), 0.88±0.20 mm for [11C]MeDAS (n = 15), 0.64±0.28mm for [11C]PK11195 (n = 19), 0.34±0.15mm for [11C]raclopride (n = 6), and 0.40±0.13mm for [99mTc]HMPAO (n = 15). These values were smallest with tracer-specific templates, when compared to the use of [18F]FDG as reference template (p&0.001). Additionally, registration errors were smallest with strain-specific templates (p&0.05), and when images and templates had the same size (p?0.001). Moreover, highest registration errors were found for the focal lesion group (p&0.005) and the diffuse lesion group (p = n.s.). In the voxel-based analysis, the reported coordinates of the focal lesion model are consistent with the stereotaxic injection procedure. The use of PET/SPECT strain- and tracer-specific templates allows accurate registration of functional rat brain data, independent of disease specific uptake patterns and with registration error below spatial resolution of the cameras. The templates and the SAMIT package will be freely available for the research community. PMID:25823005

  9. Low Resolution Data-Independent Acquisition in an LTQ-Orbitrap Allows for Simplified and Fully Untargeted Analysis of Histone Modifications.

    PubMed

    Sidoli, Simone; Simithy, Johayra; Karch, Kelly R; Kulej, Katarzyna; Garcia, Benjamin A

    2015-11-17

    Label-free peptide quantification in liquid chromatography-mass spectrometry (LC-MS) proteomics analyses is complicated by the presence of isobaric coeluting peptides, as they generate the same extracted ion chromatogram corresponding to the sum of their intensities. Histone proteins are especially prone to this, as they are heavily modified by post-translational modifications (PTMs). Their proteolytic digestion leads to a large number of peptides sharing the same mass, while carrying PTMs on different amino acid residues. We present an application of MS data-independent acquisition (DIA) to confidently determine and quantify modified histone peptides. By introducing the use of low-resolution MS/MS DIA, we demonstrate that the signals of 111 histone peptides could easily be extracted from LC-MS runs due to the relatively low sample complexity. By exploiting an LTQ-Orbitrap mass spectrometer, we parallelized MS and MS/MS scan events using the Orbitrap and the linear ion trap, respectively, decreasing the total scan time. This, in combination with large windows for MS/MS fragmentation (50 m/z) and multiple full scan events within a DIA duty cycle, led to a MS scan cycle speed of ?45 full MS per minute, improving the definition of extracted LC-MS chromatogram profiles. By using such acquisition method, we achieved highly comparable results to our optimized acquisition method for histone peptide analysis (R(2) correlation > 0.98), which combines data-dependent acquisition (DDA) and targeted MS/MS scans, the latter targeting isobaric peptides. By using DIA, we could also remine our data set and quantify 16 additional isobaric peptides commonly not targeted during DDA experiments. Finally, we demonstrated that by performing the full MS scan in the linear ion trap, we achieve highly comparable results as when adopting high-resolution MS scans (R(2) correlation 0.97). Taken together, results confirmed that histone peptide analysis can be performed using DIA and low-resolution MS with high accuracy and precision of peptide quantification. Moreover, DIA intrinsically enables data remining to later identify and quantify isobaric peptides unknown at the time of the LC-MS experiment. These methods will open up epigenetics analyses to the proteomics community who do not have routine access to the newer generation high-resolution MS/MS generating instruments. PMID:26505526

  10. Brain abscess

    MedlinePLUS

    ... abscess deep in the brain An abscess and meningitis Several abscesses (rare) Shunts in the brain for ... Complications may include: Brain damage Meningitis that is severe and life threatening Return (recurrence) of infection Seizures

  11. Brain surgery

    MedlinePLUS

    Craniotomy; Surgery - brain; Neurosurgery; Craniectomy; Stereotactic craniotomy; Stereotactic brain biopsy; Endoscopic craniotomy ... cut depends on where the problem in the brain is located. The surgeon creates a hole in ...

  12. Brain Malformations

    MedlinePLUS

    Most brain malformations begin long before a baby is born. Something damages the developing nervous system or causes it ... medicines, infections, or radiation during pregnancy interferes with brain development. Parts of the brain may be missing, ...

  13. Brain components

    MedlinePLUS Videos and Cool Tools

    The brain is composed of more than a thousand billion neurons. Specific groups of them, working in concert, provide ... of information. The 3 major components of the brain are the cerebrum, cerebellum, and brain stem. The ...

  14. Brain Tumors

    MedlinePLUS

    ... brain. Brain tumors can be benign, with no cancer cells, or malignant, with cancer cells that grow quickly. Some are primary brain ... targeted therapy. Targeted therapy uses substances that attack cancer cells without harming normal cells. Many people get ...

  15. Fast attainment of computer cursor control with noninvasively acquired brain signals

    NASA Astrophysics Data System (ADS)

    Bradberry, Trent J.; Gentili, Rodolphe J.; Contreras-Vidal, José L.

    2011-06-01

    Brain-computer interface (BCI) systems are allowing humans and non-human primates to drive prosthetic devices such as computer cursors and artificial arms with just their thoughts. Invasive BCI systems acquire neural signals with intracranial or subdural electrodes, while noninvasive BCI systems typically acquire neural signals with scalp electroencephalography (EEG). Some drawbacks of invasive BCI systems are the inherent risks of surgery and gradual degradation of signal integrity. A limitation of noninvasive BCI systems for two-dimensional control of a cursor, in particular those based on sensorimotor rhythms, is the lengthy training time required by users to achieve satisfactory performance. Here we describe a novel approach to continuously decoding imagined movements from EEG signals in a BCI experiment with reduced training time. We demonstrate that, using our noninvasive BCI system and observational learning, subjects were able to accomplish two-dimensional control of a cursor with performance levels comparable to those of invasive BCI systems. Compared to other studies of noninvasive BCI systems, training time was substantially reduced, requiring only a single session of decoder calibration (~20 min) and subject practice (~20 min). In addition, we used standardized low-resolution brain electromagnetic tomography to reveal that the neural sources that encoded observed cursor movement may implicate a human mirror neuron system. These findings offer the potential to continuously control complex devices such as robotic arms with one's mind without lengthy training or surgery.

  16. A Comparative Synthetic Spectral Analysis of the Low Resolution IUE Spectra of Two Dwarf Novae in Outburst: RX Andromeda and T Leonis

    NASA Astrophysics Data System (ADS)

    Belle, K.; Nguyen, Q.; Fabian, D.; Haung, M.; Sion, E. M.

    1995-12-01

    The IUE archive contains numerous low resolution spectra of dwarf novae in outburst but relatively little synthetic spectral analyses of them using realistic accretion disk models. Therefore, with the codes TLUSTY, SYNSPEC and DISKSYN (Hubeny 1988, 1995) we have constructed a grid of optically thick accretion disk models for white dwarf masses 0.6 and 1.0 M_sun, accretion rates -11 <= log dot {M} (M_sun/yr) <= -7, and for disk inclination angles of 40deg and 80deg . As a pilot application of our grid of models to the archival IUE spectra, we have selected two dwarf novae, one above the period gap, RX Andromeda, and one below the period gap, T Leo. We present the results of our detailed synthetic disk spectral fitting to these two systems and compare their accretion rates and disk parameters. This work has been supported by NASA LTSA grant NAGW-3726 and by a summer research grant from the NASA Delaware Space Grant Colleges Consortium.

  17. SPITZER INFRARED LOW-RESOLUTION SPECTROSCOPIC STUDY OF BURIED ACTIVE GALACTIC NUCLEI IN A COMPLETE SAMPLE OF NEARBY ULTRALUMINOUS INFRARED GALAXIES

    SciTech Connect

    Imanishi, Masatoshi; Maiolino, Roberto; Nakagawa, Takao

    2010-02-01

    We present the results of Spitzer Infrared Spectrograph low-resolution infrared 5-35 mum spectroscopy of 17 nearby ultraluminous infrared galaxies (ULIRGs) at z < 0.2, optically classified as non-Seyferts. The presence of optically elusive, but intrinsically luminous, buried active galactic nuclei (AGNs) is investigated, based on the strengths of polycyclic aromatic hydrocarbon emission and silicate dust absorption features detected in the spectra. The signatures of luminous buried AGNs, whose intrinsic luminosities range up to approx10{sup 12} L{sub sun}, are found in eight sources. We combine these results with those of our previous research to investigate the energy function of buried AGNs in a complete sample of optically non-Seyfert ULIRGs in the local universe at z < 0.3 (85 sources). We confirm a trend that we previously discovered: that buried AGNs are more common in galaxies with higher infrared luminosities. Because optical Seyferts also show a similar trend, we argue more generally that the energetic importance of AGNs is intrinsically higher in more luminous galaxies, suggesting that the AGN-starburst connections are luminosity dependent. This may be related to the stronger AGN feedback scenario in currently more massive galaxy systems, as a possible origin of the galaxy downsizing phenomenon.

  18. Development of a low resolution (1)H NMR spectroscopic technique for the study of matrix mobility in fresh and freeze-thawed hen egg yolk.

    PubMed

    Au, Carmen; Wang, Tong; Acevedo, Nuria C

    2016-08-01

    Three experiments were conducted in developing a low resolution proton nuclear magnetic resonance ((1)H NMR) spectroscopic technique to study matrix mobility in fresh and freeze-thawed gelled yolk. The Carr-Purcell-Meiboom-Gill (CPMG) sequence was used to measure spin-spin relaxation times of proton pools representing major yolk constituents. A component identification test distinguished 3-4 pools. The least mobile pool was assigned to proteins, protein-lipid and protein-water interactions, and the most mobile to unbound water. The remaining pools were assigned to lipids, lipid-protein and lipid-water interactions. A stability test indicated that yolk had varied matrix mobility within the same sample across five days of refrigeration storage. A reproducibility test demonstrated high repeatability of fresh yolk measurements, but significant differences (p<0.05) were found within gelled yolk samples. This research determined that (1)H NMR spectroscopy, a non-destructive technique, can identify yolk components and detect changes in the matrix. PMID:26988489

  19. Design and construction progress of LRS2-B: a new low resolution integral-field spectrograph for the Hobby-Eberly Telescope

    NASA Astrophysics Data System (ADS)

    Chonis, Taylor S.; Lee, Hanshin; Hill, Gary J.; Cornell, Mark E.; Tuttle, Sarah E.; Vattiat, Brian L.

    2012-09-01

    The upcoming Wide-Field Upgrade (WFU) has ushered in a new era of instrumentation for the Hobby-Eberly Telescope (HET). Here, we present the design, construction progress, and lab tests completed to date of the blue-optimized second generation Low Resolution Spectrograph (LRS2-B). LRS2-B is a dual-channel, fiber fed instrument that is based on the design of the Visible Integral Field Replicable Unit Spectrograph (VIRUS), which is the new flagship instrument for carrying out the HET Dark Energy eXperiment (HETDEX). LRS2-B utilizes a microlens-coupled integral field unit (IFU) that covers a 7"x12" area on the sky having unity fill-factor with ~300 spatial elements that subsample the median HET image quality. The fiber feed assembly includes an optimized dichroic beam splitter that allows LRS2-B to simultaneously observe 370 <λ(nm) < 470 and 460 < λ(nm) < 700 at fixed resolving powers of R ≍ λ/Δλ ≍ 1900 and 1200, respectively. We discuss the departures from the nominal VIRUS design, which includes the IFU, fiber feed, camera correcting optics, and volume phase holographic grisms. Additionally, the motivation for the selection of the wavelength coverage and spectral resolution of the two channels is briefly discussed. One such motivation is the follow-up study of spectrally and (or) spatially resolved Lyα emission from z ≍ 2.5 star-forming galaxies in the HETDEX survey. LRS2-B is planned to be a commissioning instrument for the HET WFU and should be on-sky during quarter 4 of 2013. Finally, we mention the current state of LRS2-R, the red optimized sister instrument of LRS2-B.

  20. Brain Autopsy

    MedlinePLUS

    ... FTD Awareness Week Event Archive FTD in the News Calendar of Events Fundraising Events Conferences Press Releases Brain Autopsy The Key to Understanding FTD A brain autopsy is essential to obtain ...

  1. Brain Diseases

    MedlinePLUS

    The brain is the control center of the body. It controls thoughts, memory, speech, and movement. It regulates the function of many organs. When the brain is healthy, it works quickly and automatically. However, ...

  2. Brain Power.

    ERIC Educational Resources Information Center

    Albrecht, Karl

    2002-01-01

    Reviews significant findings of recent brain research, including the concept of five minds: automatic, subconscious, practical, creative, and spiritual. Suggests approaches to training the brain that are related to this hierarchy of thinking. (JOW)

  3. Brain Fog

    MedlinePLUS

    ... BRAIN SPA” – both will improve brain function. • Recent scientific data show that longevity is associated with the successful management of chronic diseases, such as Sjögren’s syndrome, not ...

  4. Brain Aneurysm

    MedlinePLUS

    A brain aneurysm is an abnormal bulge or "ballooning" in the wall of an artery in the brain. They are sometimes called berry aneurysms because they ... often the size of a small berry. Most brain aneurysms produce no symptoms until they become large, ...

  5. Left Brain. Right Brain. Whole Brain

    ERIC Educational Resources Information Center

    Farmer, Lesley S. J.

    2004-01-01

    As the United States student population is becoming more diverse, library media specialists need to find ways to address these distinctive needs. However, some of these differences transcend culture, touching on variations in the brain itself. Most people have a dominant side of the brain, which can affect their personality and learning style.…

  6. Brain Basics: Know Your Brain

    MedlinePLUS

    ... version (2 MB) MOBI version (4 MB) Brain Basics: Know Your Brain Request free mailed brochure Table ... lobes ( 9 ), which lie in front of the visual areas and nest under the parietal and frontal ...

  7. Optimized brain extraction for pathological brains (optiBET).

    PubMed

    Lutkenhoff, Evan S; Rosenberg, Matthew; Chiang, Jeffrey; Zhang, Kunyu; Pickard, John D; Owen, Adrian M; Monti, Martin M

    2014-01-01

    The study of structural and functional magnetic resonance imaging data has greatly benefitted from the development of sophisticated and efficient algorithms aimed at automating and optimizing the analysis of brain data. We address, in the context of the segmentation of brain from non-brain tissue (i.e., brain extraction, also known as skull-stripping), the tension between the increased theoretical and clinical interest in patient data, and the difficulty of conventional algorithms to function optimally in the presence of gross brain pathology. Indeed, because of the reliance of many algorithms on priors derived from healthy volunteers, images with gross pathology can severely affect their ability to correctly trace the boundaries between brain and non-brain tissue, potentially biasing subsequent analysis. We describe and make available an optimized brain extraction script for the pathological brain (optiBET) robust to the presence of pathology. Rather than attempting to trace the boundary between tissues, optiBET performs brain extraction by (i) calculating an initial approximate brain extraction; (ii) employing linear and non-linear registration to project the approximate extraction into the MNI template space; (iii) back-projecting a standard brain-only mask from template space to the subject's original space; and (iv) employing the back-projected brain-only mask to mask-out non-brain tissue. The script results in up to 94% improvement of the quality of extractions over those obtained with conventional software across a large set of severely pathological brains. Since optiBET makes use of freely available algorithms included in FSL, it should be readily employable by anyone having access to such tools. PMID:25514672

  8. The Brains Behind the Brain.

    ERIC Educational Resources Information Center

    D'Arcangelo, Marcia

    1998-01-01

    Interviews with five neuroscientists--Martin Diamond, Pat Wolfe, Robert Sylwester, Geoffrey Caine, and Eric Jensen--disclose brain-research findings of practical interest to educators. Topics include brain physiology, environmental enrichment, memorization, windows of learning opportunity, brain learning capacity, attention span, student interest,…

  9. Brain death.

    PubMed

    Beresford, H R

    1999-05-01

    Current law in the United States authorizes physicians to diagnose brain death by applying generally accepted neurologic criteria for determining loss of function of the entire brain. This article offers a medical-legal perspective on problems that may arise with respect to the determination of brain death. These include the possibility of diagnostic error, conceptual disagreements that may constrain the use of neurologic criteria to diagnose death, and the conflation of brain death and loss of consciousness. This article also addresses legal aspects of the debate over whether to expand the definition of brain death to include permanent unconsciousness. Although existing laws draw a clear distinction between brain death and the persistent vegetative state, many courts have authorized removal of life support from individuals whose unconsciousness is believed to be permanent on proof that removal accords with preferences expressed before sentience was lost. PMID:10196410

  10. Abnormal Error Monitoring in Math-Anxious Individuals: Evidence from Error-Related Brain Potentials

    PubMed Central

    Suárez-Pellicioni, Macarena; Núñez-Peña, María Isabel; Colomé, Àngels

    2013-01-01

    This study used event-related brain potentials to investigate whether math anxiety is related to abnormal error monitoring processing. Seventeen high math-anxious (HMA) and seventeen low math-anxious (LMA) individuals were presented with a numerical and a classical Stroop task. Groups did not differ in terms of trait or state anxiety. We found enhanced error-related negativity (ERN) in the HMA group when subjects committed an error on the numerical Stroop task, but not on the classical Stroop task. Groups did not differ in terms of the correct-related negativity component (CRN), the error positivity component (Pe), classical behavioral measures or post-error measures. The amplitude of the ERN was negatively related to participants’ math anxiety scores, showing a more negative amplitude as the score increased. Moreover, using standardized low resolution electromagnetic tomography (sLORETA) we found greater activation of the insula in errors on a numerical task as compared to errors in a non-numerical task only for the HMA group. The results were interpreted according to the motivational significance theory of the ERN. PMID:24236212

  11. Brain Tumor Symptoms

    MedlinePLUS

    ... Brain Anatomy Brain Tumor Symptoms Headaches Seizures Memory Depression Mood Swings & Cognitive Changes Fatigue Other Symptoms Diagnosis Types of Tumors Risk Factors Brain Tumor Statistics Brain ...

  12. 45 CFR 1308.16 - Eligibility criteria: Traumatic brain injury.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 45 Public Welfare 4 2011-10-01 2011-10-01 false Eligibility criteria: Traumatic brain injury. 1308... DISABILITIES Health Services Performance Standards § 1308.16 Eligibility criteria: Traumatic brain injury. A child is classified as having traumatic brain injury whose brain injuries are caused by an...

  13. 45 CFR 1308.16 - Eligibility criteria: Traumatic brain injury.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 45 Public Welfare 4 2010-10-01 2010-10-01 false Eligibility criteria: Traumatic brain injury. 1308... DISABILITIES Health Services Performance Standards § 1308.16 Eligibility criteria: Traumatic brain injury. A child is classified as having traumatic brain injury whose brain injuries are caused by an...

  14. 45 CFR 1308.16 - Eligibility criteria: Traumatic brain injury.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 45 Public Welfare 4 2012-10-01 2012-10-01 false Eligibility criteria: Traumatic brain injury. 1308... DISABILITIES Health Services Performance Standards § 1308.16 Eligibility criteria: Traumatic brain injury. A child is classified as having traumatic brain injury whose brain injuries are caused by an...

  15. 45 CFR 1308.16 - Eligibility criteria: Traumatic brain injury.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 45 Public Welfare 4 2014-10-01 2014-10-01 false Eligibility criteria: Traumatic brain injury. 1308... DISABILITIES Health Services Performance Standards § 1308.16 Eligibility criteria: Traumatic brain injury. A child is classified as having traumatic brain injury whose brain injuries are caused by an...

  16. 45 CFR 1308.16 - Eligibility criteria: Traumatic brain injury.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 45 Public Welfare 4 2013-10-01 2013-10-01 false Eligibility criteria: Traumatic brain injury. 1308... DISABILITIES Health Services Performance Standards § 1308.16 Eligibility criteria: Traumatic brain injury. A child is classified as having traumatic brain injury whose brain injuries are caused by an...

  17. Brain injury in sports.

    PubMed

    Lloyd, John; Conidi, Frank

    2016-03-01

    OBJECT Helmets are used for sports, military, and transportation to protect against impact forces and associated injuries. The common belief among end users is that the helmet protects the whole head, including the brain. However, current consensus among biomechanists and sports neurologists indicates that helmets do not provide significant protection against concussion and brain injuries. In this paper the authors present existing scientific evidence on the mechanisms underlying traumatic head and brain injuries, along with a biomechanical evaluation of 21 current and retired football helmets. METHODS The National Operating Committee on Standards for Athletic Equipment (NOCSAE) standard test apparatus was modified and validated for impact testing of protective headwear to include the measurement of both linear and angular kinematics. From a drop height of 2.0 m onto a flat steel anvil, each football helmet was impacted 5 times in the occipital area. RESULTS Skull fracture risk was determined for each of the current varsity football helmets by calculating the percentage reduction in linear acceleration relative to a 140-g skull fracture threshold. Risk of subdural hematoma was determined by calculating the percentage reduction in angular acceleration relative to the bridging vein failure threshold, computed as a function of impact duration. Ranking the helmets according to their performance under these criteria, the authors determined that the Schutt Vengeance performed the best overall. CONCLUSIONS The study findings demonstrated that not all football helmets provide equal or adequate protection against either focal head injuries or traumatic brain injuries. In fact, some of the most popular helmets on the field ranked among the worst. While protection is improving, none of the current or retired varsity football helmets can provide absolute protection against brain injuries, including concussions and subdural hematomas. To maximize protection against head and brain injuries for football players of all ages, the authors propose thresholds for all sports helmets based on a peak linear acceleration no greater than 90 g and a peak angular acceleration not exceeding 1700 rad/sec(2). PMID:26473777

  18. Brain investigation and brain conceptualization

    PubMed Central

    Redolfi, Alberto; Bosco, Paolo; Manset, David; Frisoni, Giovanni B.

    Summary The brain of a patient with Alzheimer’s disease (AD) undergoes changes starting many years before the development of the first clinical symptoms. The recent availability of large prospective datasets makes it possible to create sophisticated brain models of healthy subjects and patients with AD, showing pathophysiological changes occurring over time. However, these models are still inadequate; representations are mainly single-scale and they do not account for the complexity and interdependence of brain changes. Brain changes in AD patients occur at different levels and for different reasons: at the molecular level, changes are due to amyloid deposition; at cellular level, to loss of neuron synapses, and at tissue level, to connectivity disruption. All cause extensive atrophy of the whole brain organ. Initiatives aiming to model the whole human brain have been launched in Europe and the US with the goal of reducing the burden of brain diseases. In this work, we describe a new approach to earlier diagnosis based on a multimodal and multiscale brain concept, built upon existing and well-characterized single modalities. PMID:24139654

  19. MR characterization of brain and brain tumor response to radiotherapy

    SciTech Connect

    Houdek, P.V.; Landy, H.J.; Quencer, R.M.; Sattin, W.; Poole, C.A.; Green, B.A.; Harmon, C.A.; Pisciotta, V.; Schwade, J.G.

    1988-07-01

    This paper describes our experience in using the T1 and T2 relaxation times for quantitative evaluation of brain and brain tumor response to radiation therapy. Twenty-two computed T1 and 22 computed T2 images were obtained from 66 routine inversion-recovery and spin-echo magnetic resonance (MR) brain scans. The relaxation times of the brain tissues, determined from the computed images, were examined as a function of the absorbed dose. Statistical evaluation of the results showed no significant difference between the relaxation times of irradiated and not irradiated tissues, including tumor and normal white matter. Influence of the magnetic field strength and imaging techniques on the computed T1 and T2 values was confirmed. We conclude that the relaxation time values, as obtained today using conventional MR scanner and standard software, are not specific enough to warrant a correct assessment of the acute radiation effect on the brain tissues.

  20. Primary brain tumors in adults.

    PubMed

    Chandana, Sreenivasa R; Movva, Sujana; Arora, Madan; Singh, Trevor

    2008-05-15

    Primary malignant brain tumors account for 2 percent of all cancers in U.S. adults. The most common malignant brain tumor is glioblastoma multiforme, and patients with this type of tumor have a poor prognosis. Previous exposure to high-dose ionizing radiation is the only proven environmental risk factor for a brain tumor. Primary brain tumors are classified based on their cellular origin and histologic appearance. Typical symptoms include persistent headache, seizures, nausea, vomiting, neurocognitive symptoms, and personality changes. A tumor can be identified using brain imaging, and the diagnosis is confirmed with histopathology. Any patient with chronic, persistent headache in association with protracted nausea, vomiting, seizures, change in headache pattern, neurologic symptoms, or positional worsening should be evaluated for a brain tumor. Magnetic resonance imaging is the preferred initial imaging study. A comprehensive neurosurgical evaluation is necessary to obtain tissue for diagnosis and for possible resection of the tumor. Primary brain tumors rarely metastasize outside the central nervous system, and there is no standard staging method. Surgical resection of the tumor is the mainstay of therapy. Postoperative radiation and chemotherapy have improved survival in patients with high-grade brain tumors. Recent developments in targeted chemotherapy provide novel treatment options for patients with tumor recurrence. Primary care physicians play an important role in the perioperative and supportive treatment of patients with primary brain tumors, including palliative care and symptom control. PMID:18533376

  1. Brain Tumor Risk Factors

    MedlinePLUS

    ... Donate Now Menu Brain Tumor Information Brain Anatomy Brain Tumor Symptoms Diagnosis Types of Tumors Tumor Grade Risk Factors Brain Tumor ... Financials News Careers Brain Tumor Information Brain Anatomy Brain Tumor Symptoms Diagnosis Types of Tumors Tumor Grade Risk Factors Brain Tumor ...

  2. Right Hemisphere Brain Damage

    MedlinePLUS

    ... Language and Swallowing / Disorders and Diseases Right Hemisphere Brain Damage [ en Español ] What is right hemisphere brain ... right hemisphere brain damage ? What is right hemisphere brain damage? Right hemisphere brain damage (RHD) is damage ...

  3. Brain imaging and brain function

    SciTech Connect

    Sokoloff, L.

    1985-01-01

    This book is a survey of the applications of imaging studies of regional cerebral blood flow and metabolism to the investigation of neurological and psychiatric disorders. Contributors review imaging techniques and strategies for measuring regional cerebral blood flow and metabolism, for mapping functional neural systems, and for imaging normal brain functions. They then examine the applications of brain imaging techniques to the study of such neurological and psychiatric disorders as: cerebral ischemia; convulsive disorders; cerebral tumors; Huntington's disease; Alzheimer's disease; depression and other mood disorders. A state-of-the-art report on magnetic resonance imaging of the brain and central nervous system rounds out the book's coverage.

  4. Functional Brain Imaging

    PubMed Central

    2006-01-01

    Executive Summary Objective The objective of this analysis is to review a spectrum of functional brain imaging technologies to identify whether there are any imaging modalities that are more effective than others for various brain pathology conditions. This evidence-based analysis reviews magnetoencephalography (MEG), magnetic resonance spectroscopy (MRS), positron emission tomography (PET), and functional magnetic resonance imaging (fMRI) for the diagnosis or surgical management of the following conditions: Alzheimer’s disease (AD), brain tumours, epilepsy, multiple sclerosis (MS), and Parkinson’s disease (PD). Clinical Need: Target Population and Condition Alzheimer’s disease is a progressive, degenerative, neurologic condition characterized by cognitive impairment and memory loss. The Canadian Study on Health and Aging estimated that there will be 97,000 incident cases (about 60,000 women) of dementia (including AD) in Canada in 2006. In Ontario, there will be an estimated 950 new cases and 580 deaths due to brain cancer in 2006. Treatments for brain tumours include surgery and radiation therapy. However, one of the limitations of radiation therapy is that it damages tissue though necrosis and scarring. Computed tomography (CT) and magnetic resonance imaging (MRI) may not distinguish between radiation effects and resistant tissue, creating a potential role for functional brain imaging. Epilepsy is a chronic disorder that provokes repetitive seizures. In Ontario, the rate of epilepsy is estimated to be 5 cases per 1,000 people. Most people with epilepsy are effectively managed with drug therapy; but about 50% do not respond to drug therapy. Surgical resection of the seizure foci may be considered in these patients, and functional brain imaging may play a role in localizing the seizure foci. Multiple sclerosis is a progressive, inflammatory, demyelinating disease of the central nervous system (CNS). The cause of MS is unknown; however, it is thought to be due to a combination of etiologies, including genetic and environmental components. The prevalence of MS in Canada is 240 cases per 100,000 people. Parkinson’s disease is the most prevalent movement disorder; it affects an estimated 100,000 Canadians. Currently, the standard for measuring disease progression is through the use of scales, which are subjective measures of disease progression. Functional brain imaging may provide an objective measure of disease progression, differentiation between parkinsonian syndromes, and response to therapy. The Technology Being Reviewed Functional Brain Imaging Functional brain imaging technologies measure blood flow and metabolism. The results of these tests are often used in conjunction with structural imaging (e.g., MRI or CT). Positron emission tomography and MRS identify abnormalities in brain tissues. The former measures abnormalities through uptake of radiotracers in the brain, while the latter measures chemical shifts in metabolite ratios to identify abnormalities. The potential role of functional MRI (fMRI) is to identify the areas of the brain responsible for language, sensory and motor function (sensorimotor cortex), rather than identifying abnormalities in tissues. Magnetoencephalography measures magnetic fields of the electric currents in the brain, identifying aberrant activity. Magnetoencephalography may have the potential to localize seizure foci and to identify the sensorimotor cortex, visual cortex and auditory cortex. In terms of regulatory status, MEG and PET are licensed by Health Canada. Both MRS and fMRI use a MRI platform; thus, they do not have a separate licence from Health Canada. The radiotracers used in PET scanning are not licensed by Health Canada for general use but can be used through a Clinical Trials Application. Review Strategy The literature published up to September 2006 was searched in the following databases: MEDLINE, MEDLINE In-Process & Other Non-Indexed Citations, EMBASE, Cochrane Database of Systematic Reviews, CENTRAL, and International Network of Agencies for H

  5. Low resolution and high resolution MS for studies on the metabolism and toxicological detection of the new psychoactive substance methoxypiperamide (MeOP).

    PubMed

    Meyer, Markus R; Holderbaum, Anna; Kavanagh, Pierce; Maurer, Hans H

    2015-10-01

    In 2013, the new psychoactive substance methoxypiperamide (MeOP) was first reported to the European Monitoring Centre for Drug and Drug Addiction. Its structural similarity to already controlled piperazine designer drugs might have contributed to the decision to offer MeOP for online purchase. The aims of this work were to identify the phase I/II metabolites of MeOP in rat urine and the human cytochrome P450 (CYP) isoenzymes responsible for the initial metabolic steps. Finally, the detectability of MeOP in rat urine by gas chromatography-mass spectrometry (GC-MS) and liquid chromatography coupled with multistage mass spectrometry (LC-MS(n)) standard urine screening approaches (SUSAs) was evaluated. After sample preparation by cleavage of conjugates followed by extraction for elucidating phase I metabolites, the analytes were separated and identified by GC-MS as well as liquid chromatography-high resolution-tandem mass spectrometry (LC-HR-MS/MS). For detection of phase II metabolites, the analytes were separated and identified after urine precipitation followed by LC-HR-MS/MS. The following metabolic steps could be postulated: hydrolysis of the amide, N-oxide formation, N- and/or O-demethylation, oxidation of the piperazine ring to the corresponding keto-piperazine, piperazine ring opening followed by oxidation of a methylene group to the corresponding imide, and hydroxylation of the phenyl group. Furthermore, N-acetylation, glucuronidation and sulfation were observed. Using human CYPs, CYP1A2, CYP2C19, CYP2D6, and/or CYP3A4 were found to catalyze N-oxide formation and N-, O-demethylation and/or oxidation. Mostly MeOP and N-oxide-MeOP but to a minor degree also other metabolites could be detected in the GC-MS and LC-MS(n) SUSAs. PMID:26456786

  6. Organic brain syndrome

    MedlinePLUS

    OBS; Organic mental disorder (OMS); Chronic organic brain syndrome ... Listed below are disorders associated with OBS. Brain injury caused by ... the brain ( subarachnoid hemorrhage ) Blood clot inside the ...

  7. [Brain tumors].

    PubMed

    Hatano, Manabu; Mizuno, Masaaki; Yoshida, Jun

    2003-04-01

    Brain tumors generally arise as the culmination of a multistep process that involves a variety of genetic abnormalities. Theoretically, replacement of abnormal genes with normal genes is essential to brain tumor treatment. However, it is very difficult to replace all damaged genes. Currently, most clinical protocols for gene therapy in brain tumors include transfer of a gene which can induce tumor cells to die or which can enhance the environment to generate a systemic immune response against the tumor. The former strategy includes suicide gene therapies, tumor suppressor gene therapy and oncolytic virus therapy. The latter adopts immunogene therapy. In this report, we also focus on other gene therapies, such as therapies to control the cell cycle or apoptosis, and promote antiangiogenesis. Gene therapy is generally accepted to be rather safe in recent years. In fact, the current single-gene therapies for brain tumor are limited and probably restricted to a few tumors. Several agents with different mechanisms of action would be necessary to kill heterogenously mixed tumor cells. Further molecular techniques and basic studies may overcome the malignancy of cancers. PMID:12722674

  8. Brain Basics

    MedlinePLUS

    ... and are working to compare that with brain development in people mental disorders. Genes and environmental cues both help to direct this growth. The Changing Brain—Effects of Genes and the Environment There are many different types of cells in ...

  9. Brain-Compatible Assessments. Second Edition

    ERIC Educational Resources Information Center

    Ronis, Diane L.

    2007-01-01

    Diane Ronis, a recognized expert in brain-compatible learning and assessment, goes beyond the world of standardized testing to show educators how to build and use targeted assessments based on the latest neuroscientific research. Updated to reflect recent findings about how the brain learns, this book provides readers with revised tools for…

  10. Analysis of time-series of total and plant water stress levels using a dual-source energy balance model over agricultural crops and medium to low resolution thermal infra red remote sensing data

    NASA Astrophysics Data System (ADS)

    Boulet, Gilles; Mougenot, Bernard; Bahir, Malik; Fanise, Pascal; Saadi, Sameh; Simonneaux, Vincent; Chebbi, Wafa; Kassouk, Zeineb; Oualid, Toufik; Olioso, Albert; Lagouarde, Jean-Pierre; Le Dantec, Valérie; Rivalland, Vincent; Zribi, Mehrez; Lili-Chabaane, Zohra

    2015-04-01

    Detecting, monitoring and mapping plant water stress with remote sensing data is a crucial component of modern agricultural water management, especially in areas with scarce water resources such as the south and the eastern parts of the Mediterranean region. Developing efficient operational methods dedicated to those three actions is thus necessary to design observing systems for areas with a mixture of irrigated, rainfed and deficit irrigation agriculture. Those systems can assist managers in tasks such as early warning of drought, real time irrigated area mapping etc. A way to quantify plant and total water stress levels is to exploit the available surface temperature data from remote sensing as a signature of the surface energy balance, including the latent heat flux. Remotely sensed energy balance models enable to estimate evapotranspiration and the water status of continental surfaces. Two-source models, such as TSEB (Norman et al., 1995) allow deriving a rough estimate of the water stress of the vegetation instead of that of a soil-vegetation composite. For the latter, a realistic underlying assumption enables to invert two unknowns (evaporation and transpiration) from a single piece of information. This assumption states that, in most cases, vegetation is unstressed, and that if vegetation is stressed, evaporation is negligible. In the latter case, if vegetation stress is not properly accounted for, the resulting evaporation will decrease to unrealistic levels (negative fluxes) in order to maintain the same total surface temperature. Actual and potential transpiration rates are combined to derive an index of plant water stress applicable to low resolution data. Here, we evaluate time series of plant water stress indices in the Kairouan area in Central Tunisia in the last few years by comparing them with 1- maps of the irrigation sectors as well as rainfall data and 2- turbulent heat flux measurements obtained at low resolution (scintillometer, eddy-covariance over homogeneous areas) and 3- outputs of a distributed hydrological model (SAMIR).

  11. Understanding Brain Tumors

    MedlinePLUS

    ... to Know About Brain Tumors . What is a Brain Tumor? A brain tumor is an abnormal growth
 ... Tumors” from Frankly Speaking Frankly Speaking About Cancer: Brain Tumors Download the full book Questions to ask ...

  12. Brain and Nervous System

    MedlinePLUS

    ... Allergy Emergency Cerebral Palsy: Caring for Your Child Brain and Nervous System KidsHealth > For Parents > Brain and ... and remove waste products. continue All About the Brain The brain is made up of three main ...

  13. Brain Tumors (For Parents)

    MedlinePLUS

    ... Allergy Emergency Cerebral Palsy: Caring for Your Child Brain Tumors KidsHealth > For Parents > Brain Tumors Print A ... radiation therapy or chemotherapy, or both. Types of Brain Tumors There are many different types of brain ...

  14. Brain Aneurysm Foundation

    MedlinePLUS

    ... Sign-Up Contact Us Understanding Brain Aneurysm Basics Warning Signs/Symptoms Brain Aneurysm Statistics and Facts Seeking Medical Attention Pediatric Aneurysms Brain Aneurysm Causes and Risk Factors Family History Early Detection and Screening Unruptured Brain Aneurysms Subarachnoid Hemorrhage ...

  15. Brain Aneurysm: Recovery

    MedlinePLUS

    ... Sign-Up Contact Us Understanding Brain Aneurysm Basics Warning Signs/Symptoms Brain Aneurysm Statistics and Facts Seeking Medical Attention Pediatric Aneurysms Brain Aneurysm Causes and Risk Factors Family History Early Detection and Screening Unruptured Brain Aneurysms Subarachnoid Hemorrhage ...

  16. Brain Aneurysm: Treatment Options

    MedlinePLUS

    ... Sign-Up Contact Us Understanding Brain Aneurysm Basics Warning Signs/Symptoms Brain Aneurysm Statistics and Facts Seeking Medical Attention Pediatric Aneurysms Brain Aneurysm Causes and Risk Factors Family History Early Detection and Screening Unruptured Brain Aneurysms Subarachnoid Hemorrhage ...

  17. Unruptured Brain Aneurysms

    MedlinePLUS

    ... Sign-Up Contact Us Understanding Brain Aneurysm Basics Warning Signs/Symptoms Brain Aneurysm Statistics and Facts Seeking Medical Attention Pediatric Aneurysms Brain Aneurysm Causes and Risk Factors Family History Early Detection and Screening Unruptured Brain Aneurysms Subarachnoid Hemorrhage ...

  18. Brain Tumor Diagnosis

    MedlinePLUS

    ... Financials News Careers Brain Tumor Information Brain Anatomy Brain Tumor Symptoms Diagnosis Types of Tumors Tumor Grade Risk Factors Brain Tumor ... Brain Tumor Symptoms Diagnosis Newly Diagnosed Neurological Exam Types of Brain Scans X-rays Laboratory Tests DNA Profiling Biopsy ...

  19. The Creative Brain.

    ERIC Educational Resources Information Center

    Herrmann, Ned

    1982-01-01

    Outlines the differences between left-brain and right-brain functioning and between left-brain and right-brain dominant individuals, and concludes that creativity uses both halves of the brain. Discusses how both students and curriculum can become more "whole-brained." (Author/JM)

  20. Emulation to simulate low resolution atmospheric data

    SciTech Connect

    Hebbur Venkata Subba Rao, Vishwas; Archibald, Richard K; Evans, Katherine J

    2012-08-01

    Climate simulations require significant compute power, they are complex and therefore it is time consuming to simulate them. We have developed an emulator to simulate unknown climate datasets. The emulator uses stochastic collocation and multi-dimensional in- terpolation to simulate the datasets. We have used the emulator to determine various physical quantities such as temperature, short and long wave cloud forcing, zonal winds etc. The emulation gives results which are very close to those obtained by simulations. The emulator was tested on 2 degree atmospheric datasets. The work evaluates the pros and cons of evaluating the mean first and inter- polating and vice versa. To determine the physical quantities, we have assumed them to be a function of time, longitude, latitude and a random parameter. We have looked at parameters that govern high stable clouds, low stable clouds, timescale for convection etc. The emulator is especially useful as it requires negligible compute times when compared to the simulation itself.

  1. Martian 'Brain'

    NASA Technical Reports Server (NTRS)

    2004-01-01

    5 May 2004 Most middle-latitude craters on Mars have strange landforms on their floors. Often, the floors have pitted and convoluted features that lack simple explanation. In this case, the central part of the crater floor shown in this 2004 Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image bears some resemblance to the folded nature of a brain. Or not. It depends upon the 'eye of the beholder,' perhaps. The light-toned 'ring' around the 'brain' feature is more easily explained--windblown ripples and dunes. The crater occurs near 33.1oS, 91.2oW, and is illuminated from the upper left. The picture covers an area about 3 km (1.9 mi) across.

  2. Silicon Brains

    NASA Astrophysics Data System (ADS)

    Hoefflinger, Bernd

    Beyond the digital neural networks of Chap. 16, the more radical mapping of brain-like structures and processes into VLSI substrates has been pioneered by Carver Mead more than 30 years ago [1]. The basic idea was to exploit the massive parallelism of such circuits and to create low-power and fault-tolerant information-processing systems. Neuromorphic engineering has recently seen a revival with the availability of deep-submicron CMOS technology, which allows for the construction of very-large-scale mixed-signal systems combining local analog processing in neuronal cells with binary signalling via action potentials. Modern implementations are able to reach the complexity-scale of large functional units of the human brain, and they feature the ability to learn by plasticity mechanisms found in neuroscience. Combined with high-performance programmable logic and elaborate software tools, such systems are currently evolving into user-configurable non-von-Neumann computing systems, which can be used to implement and test novel computational paradigms. The chapter introduces basic properties of biological brains with up to 200 Billion neurons and their 1014 synapses, where action on a synapse takes ˜10 ms and involves an energy of ˜10 fJ. We outline 10x programs on neuromorphic electronic systems in Europe and the USA, which are intended to integrate 108 neurons and 1012 synapses, the level of a cat's brain, in a volume of 1 L and with a power dissipation <1 kW. For a balanced view on intelligence, we references Hawkins' view to first perceive the task and then design an intelligent technical response.

  3. Brain imaging

    SciTech Connect

    Bradshaw, J.R.

    1989-01-01

    This book presents a survey of the various imaging tools with examples of the different diseases shown best with each modality. It includes 100 case presentations covering the gamut of brain diseases. These examples are grouped according to the clinical presentation of the patient: headache, acute headache, sudden unilateral weakness, unilateral weakness of gradual onset, speech disorders, seizures, pituitary and parasellar lesions, sensory disorders, posterior fossa and cranial nerve disorders, dementia, and congenital lesions.

  4. Study on Control of Brain Temperature for Brain Hypothermia Treatment

    NASA Astrophysics Data System (ADS)

    Gaohua, Lu; Wakamatsu, Hidetoshi

    The brain hypothermia treatment is an attractive therapy for the neurologist because of its neuroprotection in hypoxic-ischemic encephalopathy patients. The present paper deals with the possibility of controlling the brain and other viscera in different temperatures from the viewpoint of system control. It is theoretically attempted to realize the special brain hypothermia treatment to cool only the head but to warm the body by using the simple apparatus such as the cooling cap, muffler and warming blanket. For this purpose, a biothermal system concerning the temperature difference between the brain and the other thoracico-abdominal viscus is synthesized from the biothermal model of hypothermic patient. The output controllability and the asymptotic stability of the system are examined on the basis of its structure. Then, the maximum temperature difference to be realized is shown dependent on the temperature range of the apparatus and also on the maximum gain determined from the coefficient matrices A, B and C of the biothermal system. Its theoretical analysis shows the realization of difference of about 2.5°C, if there is absolutely no constraint of the temperatures of the cooling cap, muffler and blanket. It is, however, physically unavailable. Those are shown by simulation example of the optimal brain temperature regulation using a standard adult database. It is thus concluded that the surface cooling and warming apparatus do no make it possible to realize the special brain hypothermia treatment, because the brain temperature cannot be cooled lower than those of other viscera in an appropriate temperature environment. This study shows that the ever-proposed good method of clinical treatment is in principle impossible in the actual brain hypothermia treatment.

  5. Mouse brain imaging using photoacoustic computed tomography

    NASA Astrophysics Data System (ADS)

    Lou, Yang; Xia, Jun; Wang, Lihong V.

    2014-03-01

    Photoacoustic computed tomography (PACT) provides structural and functional information when used in small animal brain imaging. Acoustic distortion caused by bone structures largely limits the deep brain image quality. In our work, we present ex vivo PACT images of freshly excised mouse brain, intending that can serve as a gold standard for future PACT in vivo studies on small animal brain imaging. Our results show that structures such as the striatum, hippocampus, ventricles, and cerebellum can be clearly di erentiated. An artery feature called the Circle of Willis, located at the bottom of the brain, can also be seen. These results indicate that if acoustic distortion can be accurately accounted for, PACT should be able to image the entire mouse brain with rich structural information.

  6. Brain Imaging

    PubMed Central

    Racine, Eric; Bar-Ilan, Ofek; Illes, Judy

    2007-01-01

    Advances in neuroscience are increasingly intersecting with issues of ethical, legal, and social interest. This study is an analysis of press coverage of an advanced technology for brain imaging, functional magnetic resonance imaging, that has gained significant public visibility over the past ten years. Discussion of issues of scientific validity and interpretation dominated over ethical content in both the popular and specialized press. Coverage of research on higher order cognitive phenomena specifically attributed broad personal and societal meaning to neuroimages. The authors conclude that neuroscience provides an ideal model for exploring science communication and ethics in a multicultural context. PMID:17330151

  7. Sleep and Traumatic Brain Injury.

    PubMed

    Baumann, Christian R

    2016-03-01

    Post-traumatic sleep-wake disturbances are frequent and often chronic complications after traumatic brain injury. The most prevalent sleep-wake disturbances are insomnia, excessive daytime sleepiness, and pleiosomnia, (ie, increased sleep need). These disturbances are probably of multifactorial origin, but direct traumatic damage to key brain structures in sleep-wake regulation is likely to contribute. Diagnosis and treatment consist of standard approaches, but because of misperception of sleep-wake behavior in trauma patients, subjective testing alone may not always suffice. PMID:26972030

  8. Dysautonomia after pediatric brain injury

    PubMed Central

    KIRK, KATHERINE A; SHOYKHET, MICHAEL; JEONG, JONG H; TYLER-KABARA, ELIZABETH C; HENDERSON, MARYANNE J; BELL, MICHAEL J; FINK, ERICKA L

    2012-01-01

    AIM Dysautonomia after brain injury is a diagnosis based on fever, tachypnea, hypertension, tachycardia, diaphoresis, and/or dystonia. It occurs in 8 to 33% of brain-injured adults and is associated with poor outcome. We hypothesized that brain-injured children with dysautonomia have worse outcomes and prolonged rehabilitation, and sought to determine the prevalence of dysautonomia in children and to characterize its clinical features. METHOD We developed a database of children (n=249, 154 males, 95 females; mean (SD) age 11y 10mo [5y 7mo]) with traumatic brain injury, cardiac arrest, stroke, infection of the central nervous system, or brain neoplasm admitted to The Children’s Institute of Pittsburgh for rehabilitation between 2002 and 2009. Dysautonomia diagnosis, injury type, clinical signs, length of stay, and Functional Independence Measure for Children (WeeFIM) testing were extracted from medical records, and analysed for differences between groups with and without dysautonomia. RESULTS Dysautonomia occurred in 13% of children with brain injury (95% confidence interval 9.3–18.0%), occurring in 10% after traumatic brain injury and 31% after cardiac arrest. The combination of hypertension, diaphoresis, and dystonia best predicted a diagnosis of dysautonomia (area under the curve=0.92). Children with dysautonomia had longer stays, worse WeeFIM scores, and improved less on the score’s motor component (all p≤0.001). INTERPRETATION Dysautonomia is common in children with brain injury and is associated with prolonged rehabilitation. Prospective study and standardized diagnostic approaches are needed to maximize outcomes. PMID:22712762

  9. Brain Tumors

    PubMed Central

    Herholz, Karl; Langen, Karl-Josef; Schiepers, Christiaan; Mountz, James M.

    2014-01-01

    This review addresses the specific contributions of nuclear medicine techniques, and especially positron emission tomography (PET), for diagnosis and management of brain tumors. 18F-Fluorodeoxyglucose PET has particular strengths in predicting prognosis and differentiating cerebral lymphoma from nonmalignant lesions. Amino acid tracers including 11C-methionine, 18F-fluoroethyltyrosine, and 18F-l-3,4-dihydroxyphenylalanine provide high sensitivity, which is most useful for detecting recurrent or residual gliomas, including most low-grade gliomas. They also play an increasing role for planning and monitoring of therapy. 18F-fluorothymidine can only be used in tumors with absent or broken blood–brain barrier and has potential for tumor grading and monitoring of therapy. Ligands for somatostatin receptors are of particular interest in pituitary adenomas and meningiomas. Tracers to image neovascularization, hypoxia, and phospholipid synthesis are under investigation for potential clinical use. All methods provide the maximum of information when used with image registration and fusion display with contrast-enhanced magnetic resonance imaging scans. Integration of PET and magnetic resonance imaging with stereotactic neuronavigation systems allows the targeting of stereotactic biopsies to obtain a more accurate histologic diagnosis and better planning of conformal and stereotactic radiotherapy. PMID:23026359

  10. Brain tumor - primary - adults

    MedlinePLUS

    ... and do not increase the risk. SPECIFIC TUMOR TYPES Brain tumors are classified depending on: Location of the ... brain tumor. Meningiomas and schwannomas are two other types of brain tumors. These tumors: Occur most often between ages ...

  11. Traumatic Brain Injury

    MedlinePLUS

    Traumatic brain injury (TBI) happens when a bump, blow, jolt, or other head injury causes damage to the brain. Every year, millions of people in the U.S. suffer brain injuries. More than half are bad enough that ...

  12. Mild Traumatic Brain Injury

    MedlinePLUS

    ... Questions Glossary Contact Us Visitor Feedback mild Traumatic Brain Injury mild Traumatic Brain Injury VIDEO STORIES What is TBI? Measuring Severity ... most common deployment injuries is a mild Traumatic Brain Injury (TBI). A mild TBI is an injury ...

  13. Traumatic Brain Injury

    MedlinePLUS

    ... Center PTACs Workspaces Log-in Search for: Traumatic Brain Injury A legacy resource from NICHCY Disability Fact ... in her. Back to top What is Traumatic Brain Injury? A traumatic brain injury (TBI) is an ...

  14. Brain-Controlled Prosthetics

    MedlinePLUS

    ... neuroscientists have significantly advanced brain-computer interface (BCI) technology to the point where severely physically disabled people ... a brain-computer interface (BCI), scientists have developed technology that enables communication between brain activity and an ...

  15. That's Using Your Brain!

    ERIC Educational Resources Information Center

    Visser, Dana R.

    1996-01-01

    Discusses new adult learning theories, including those of Roger Sperry (left brain/right brain), Paul McLean (triune brain), and Howard Gardner (multiple intelligences). Relates adult learning theory to training. (JOW)

  16. Special Report: Brain Chemistry.

    ERIC Educational Resources Information Center

    Krassner, Michael B.

    1983-01-01

    Chemical actions in the brain result in cognitive, emotional, neuroendocrine, neuromuscular, and/or neurocirculatory effects. Developments in understanding brain chemistry are discussed, considering among others, neurotransmitter chemistry, neuropeptides, drugs and the brain, antidepressants, and actions of minor tranquilizers. (JN)

  17. American Brain Tumor Association

    MedlinePLUS

    ... 5, phase 2/3 clinical trial for recurrent brain cancer to Canada Rindopepimut Misses OS Endpoint in Phase ... tumors Enhancing immune system may boost survival for brain cancer patients Read More ABTA News American Brain Tumor ...

  18. Brain tumor (image)

    MedlinePLUS

    Brain tumors are classified depending on the exact site of the tumor, the type of tissue involved, benign ... tendencies of the tumor, and other factors. Primary brain tumors can arise from the brain cells, the meninges ( ...

  19. Brain Tumor Statistics

    MedlinePLUS

    ... Our Founders Board of Directors Staff Leadership Strategic Plan Financials News Careers Brain Tumor Information Brain Anatomy Brain Tumor Symptoms ... Our Founders Board of Directors Staff Leadership Strategic ... Contacts Careers Donate to the ABTA Help advance the understanding ...

  20. Brain-based Learning.

    ERIC Educational Resources Information Center

    Weiss, Ruth Palombo

    2000-01-01

    Discusses brain research and how new imaging technologies allow scientists to explore how human brains process memory, emotion, attention, patterning, motivation, and context. Explains how brain research is being used to revise learning theories. (JOW)

  1. PCA and level set based non-rigid image registration for MRI and Paxinos-Watson atlas of rat brain

    NASA Astrophysics Data System (ADS)

    Cai, Chao; Liu, Ailing; Ding, Mingyue; Zhou, Chengping

    2007-12-01

    Image registration provides the ability to geometrically align one dataset with another. It is a basic task in a great variety of biomedical imaging applications. This paper introduced a novel three-dimensional registration method for Magnetic Resonance Image (MRI) and Paxinos-Watson Atlas of rat brain. For the purpose of adapting to a large range and non-linear deformation between MRI and atlas in higher registration accuracy, based on the segmentation of rat brain, we chose the principle components analysis (PCA) automatically performing the linear registration, and then, a level set based nonlinear registration correcting some small distortions. We implemented this registration method in a rat brain 3D reconstruction and analysis system. Experiments have demonstrated that this method can be successfully applied to registering the low resolution and noise affection MRI with Paxinos-Watson Atlas of rat brain.

  2. Inhibition and Brain Work

    PubMed Central

    Buzsáki, György; Kaila, Kai; Raichle, Marcus

    2008-01-01

    The major part of the brain’s energy budget (~60%–80%) is devoted to its communication activities. While inhibition is critical to brain function, relatively little attention has been paid to its metabolic costs. Understanding how inhibitory interneurons contribute to brain energy consumption (brain work) is not only of interest in understanding a fundamental aspect of brain function but also in understanding functional brain imaging techniques which rely on measurements related to blood flow and metabolism. Herein we examine issues relevant to an assessment of the work performed by inhibitory interneurons in the service of brain function. PMID:18054855

  3. Training Standardization

    SciTech Connect

    Agnihotri, Newal

    2003-09-01

    The article describes the benefits of and required process and recommendations for implementing the standardization of training in the nuclear power industry in the United States and abroad. Current Information and Communication Technologies (ICT) enable training standardization in the nuclear power industry. The delivery of training through the Internet, Intranet and video over IP will facilitate this standardization and bring multiple benefits to the nuclear power industry worldwide. As the amount of available qualified and experienced professionals decreases because of retirements and fewer nuclear engineering institutions, standardized training will help increase the number of available professionals in the industry. Technology will make it possible to use the experience of retired professionals who may be interested in working part-time from a remote location. Well-planned standardized training will prevent a fragmented approach among utilities, and it will save the industry considerable resources in the long run. It will also ensure cost-effective and safe nuclear power plant operation.

  4. Revisiting Einstein's brain in Brain Awareness Week.

    PubMed

    Chen, Hao; Chen, Su; Zeng, Lidan; Zhou, Lin; Hou, Shengtao

    2014-10-01

    Albert Einstein's brain has long been an object of fascination to both neuroscience specialists and the general public. However, without records of advanced neuro-imaging of his brain, conclusions regarding Einstein's extraordinary cognitive capabilities can only be drawn based on the unique external features of his brain and through comparison of the external features with those of other human brain samples. The recent discovery of 14 previously unpublished photographs of Einstein's brain taken at unconventional angles by Dr. Thomas Stoltz Harvey, the pathologist, ignited a renewed frenzy about clues to explain Einstein's genius. Dr. Dean Falk and her colleagues, in their landmark paper published in Brain (2013; 136:1304-1327), described in such details about the unusual features of Einstein's brain, which shed new light on Einstein's intelligence. In this article, we ask what are the unique structures of his brain? What can we learn from this new information? Can we really explain his extraordinary cognitive capabilities based on these unique brain structures? We conclude that studying the brain of a remarkable person like Albert Einstein indeed provides us a better example to comprehensively appreciate the relationship between brain structures and advanced cognitive functions. However, caution must be exercised so as not to over-interpret his intelligence solely based on the understanding of the surface structures of his brain. PMID:25382446

  5. Decoding brain responses to pixelized images in the primary visual cortex: implications for visual cortical prostheses.

    PubMed

    Guo, Bing-Bing; Zheng, Xiao-Lin; Lu, Zhen-Gang; Wang, Xing; Yin, Zheng-Qin; Hou, Wen-Sheng; Meng, Ming

    2015-10-01

    Visual cortical prostheses have the potential to restore partial vision. Still limited by the low-resolution visual percepts provided by visual cortical prostheses, implant wearers can currently only "see" pixelized images, and how to obtain the specific brain responses to different pixelized images in the primary visual cortex (the implant area) is still unknown. We conducted a functional magnetic resonance imaging experiment on normal human participants to investigate the brain activation patterns in response to 18 different pixelized images. There were 100 voxels in the brain activation pattern that were selected from the primary visual cortex, and voxel size was 4 mm × 4 mm × 4 mm. Multi-voxel pattern analysis was used to test if these 18 different brain activation patterns were specific. We chose a Linear Support Vector Machine (LSVM) as the classifier in this study. The results showed that the classification accuracies of different brain activation patterns were significantly above chance level, which suggests that the classifier can successfully distinguish the brain activation patterns. Our results suggest that the specific brain activation patterns to different pixelized images can be obtained in the primary visual cortex using a 4 mm × 4 mm × 4 mm voxel size and a 100-voxel pattern. PMID:26692860

  6. Decoding brain responses to pixelized images in the primary visual cortex: implications for visual cortical prostheses

    PubMed Central

    Guo, Bing-bing; Zheng, Xiao-lin; Lu, Zhen-gang; Wang, Xing; Yin, Zheng-qin; Hou, Wen-sheng; Meng, Ming

    2015-01-01

    Visual cortical prostheses have the potential to restore partial vision. Still limited by the low-resolution visual percepts provided by visual cortical prostheses, implant wearers can currently only “see” pixelized images, and how to obtain the specific brain responses to different pixelized images in the primary visual cortex (the implant area) is still unknown. We conducted a functional magnetic resonance imaging experiment on normal human participants to investigate the brain activation patterns in response to 18 different pixelized images. There were 100 voxels in the brain activation pattern that were selected from the primary visual cortex, and voxel size was 4 mm × 4 mm × 4 mm. Multi-voxel pattern analysis was used to test if these 18 different brain activation patterns were specific. We chose a Linear Support Vector Machine (LSVM) as the classifier in this study. The results showed that the classification accuracies of different brain activation patterns were significantly above chance level, which suggests that the classifier can successfully distinguish the brain activation patterns. Our results suggest that the specific brain activation patterns to different pixelized images can be obtained in the primary visual cortex using a 4 mm × 4 mm × 4 mm voxel size and a 100-voxel pattern. PMID:26692860

  7. EOS standards

    SciTech Connect

    Greeff, Carl W

    2011-01-12

    An approach to creating accurate EOS for pressure standards is described. Applications to Cu, Au, and Ta are shown. Extension of the method to high compressions using DFT is illustrated. Comparisons with modern functionals show promise.

  8. Standards Organizations

    Cancer.gov

    Health Level Screen (HL7)Founded in 1987, Health Level Seven, Inc., is a not-for-profit, ANSI-accredited, standards developing organization that provides standards for the exchange, management, and integration of data that supports clinical patient care and the management, delivery, and evaluation of healthcare services. Its 2,200 members represent over 500 corporations, including 90 percent of the largest information systems vendors serving healthcare.

  9. Networking standards

    NASA Technical Reports Server (NTRS)

    Davies, Mark

    1991-01-01

    The enterprise network is currently a multivendor environment consisting of many defacto and proprietary standards. During the 1990s, these networks will evolve towards networks which are based on international standards in both Local Area Network (LAN) and Wide Area Network (WAN) space. Also, you can expect to see the higher level functions and applications begin the same transition. Additional information is given in viewgraph form.

  10. (Terminology standardization)

    SciTech Connect

    Strehlow, R.A.

    1990-10-19

    Terminological requirements in information management was but one of the principal themes of the 2nd Congress on Terminology and Knowledge Engineering. The traveler represented the American Society for Testing and Materials' Committee on Terminology, of which he is the Chair. The traveler's invited workshop emphasized terminology standardization requirements in databases of material properties as well as practical terminology standardizing methods. The congress included six workshops in addition to approximately 82 lectures and papers from terminologists, artificial intelligence practitioners, and subject specialists from 18 countries. There were approximately 292 registrants from 33 countries who participated in the congress. The congress topics were broad. Examples were the increasing use of International Standards Organization (ISO) Standards in legislated systems such as the USSR Automated Data Bank of Standardized Terminology, the enhanced Physics Training Program based on terminology standardization in Physics in the Chinese province of Inner Mongolia, and the technical concept dictionary being developed at the Japan Electronic Dictionary Research Institute, which is considered to be the key to advanced artificial intelligence applications. The more usual roles of terminology work in the areas of machine translation. indexing protocols, knowledge theory, and data transfer in several subject specialties were also addressed, along with numerous special language terminology areas.

  11. Liposomal contrast agents in brain tumor imaging.

    PubMed

    Ghaghada, Ketan B; Colen, Rivka R; Hawley, Catherine R; Patel, Neil; Mukundan, Srinivasan

    2010-08-01

    Treatment of glioblastoma multiforme remains a major challenge despite advances in standard therapy, including surgery, radiation, and chemotherapy. The field of nanomedicine is expected to have a major impact on the treatment and management of brain tumors. Over the past decade, significant efforts have been made in using nanoparticles for diagnosis and treatment of brain tumors. One class of nanoparticles, liposomes, have received considerable attention for use as nanocarriers for delivery of therapeutics and contrast agents. The purpose of this article is to present the advances in the design and functional characteristics of liposomes for applications in brain tumor imaging. PMID:20708552

  12. Brain evolution by brain pathway duplication

    PubMed Central

    Chakraborty, Mukta; Jarvis, Erich D.

    2015-01-01

    Understanding the mechanisms of evolution of brain pathways for complex behaviours is still in its infancy. Making further advances requires a deeper understanding of brain homologies, novelties and analogies. It also requires an understanding of how adaptive genetic modifications lead to restructuring of the brain. Recent advances in genomic and molecular biology techniques applied to brain research have provided exciting insights into how complex behaviours are shaped by selection of novel brain pathways and functions of the nervous system. Here, we review and further develop some insights to a new hypothesis on one mechanism that may contribute to nervous system evolution, in particular by brain pathway duplication. Like gene duplication, we propose that whole brain pathways can duplicate and the duplicated pathway diverge to take on new functions. We suggest that one mechanism of brain pathway duplication could be through gene duplication, although other mechanisms are possible. We focus on brain pathways for vocal learning and spoken language in song-learning birds and humans as example systems. This view presents a new framework for future research in our understanding of brain evolution and novel behavioural traits. PMID:26554045

  13. Brain evolution by brain pathway duplication.

    PubMed

    Chakraborty, Mukta; Jarvis, Erich D

    2015-12-19

    Understanding the mechanisms of evolution of brain pathways for complex behaviours is still in its infancy. Making further advances requires a deeper understanding of brain homologies, novelties and analogies. It also requires an understanding of how adaptive genetic modifications lead to restructuring of the brain. Recent advances in genomic and molecular biology techniques applied to brain research have provided exciting insights into how complex behaviours are shaped by selection of novel brain pathways and functions of the nervous system. Here, we review and further develop some insights to a new hypothesis on one mechanism that may contribute to nervous system evolution, in particular by brain pathway duplication. Like gene duplication, we propose that whole brain pathways can duplicate and the duplicated pathway diverge to take on new functions. We suggest that one mechanism of brain pathway duplication could be through gene duplication, although other mechanisms are possible. We focus on brain pathways for vocal learning and spoken language in song-learning birds and humans as example systems. This view presents a new framework for future research in our understanding of brain evolution and novel behavioural traits. PMID:26554045

  14. Brain SPECT quantitation in clinical diagnosis

    SciTech Connect

    Hellman, R.S.

    1991-12-31

    Methods to quantitate SPECT data for clinical diagnosis should be chosen so that they take advantage of the lessons learned from PET data. This is particularly important because current SPECT high-resolution brain imaging systems now produce images that are similar in resolution to those generated by the last generation PET equipment (9 mm FWHM). These high-resolution SPECT systems make quantitation of SPECT more problematic than earlier. Methodology validated on low-resolution SPECT systems may no longer be valid for data obtained with the newer SPECT systems. For example, in patients with dementia, the ratio of parietal to cerebellar activity often was studied. However, with new instruments, the cerebellum appears very different: discrete regions are more apparent. The large cerebellar regions usually used with older instrumentation are of an inappropriate size for the new equipment. The normal range for any method of quantitation determined using older equipment probably changes for data obtained with new equipment. It is not surprising that Kim et al. in their simulations demonstrated that because of the finite resolution of imaging systems, the ability to measure pure function is limited, with {open_quotes}anatomy{close_quotes} and {open_quotes}function{close_quotes} coupled in a {open_quotes}complex nonlinear way{close_quotes}. 11 refs.

  15. Individualized rTMS neuronavigated according to regional brain metabolism ((18)FGD PET) has better treatment effects on auditory hallucinations than standard positioning of rTMS: a double-blind, sham-controlled study.

    PubMed

    Klirova, Monika; Horacek, Jiri; Novak, Tomas; Cermak, Jan; Spaniel, Filip; Skrdlantova, Lucie; Mohr, Pavel; Höschl, Cyril

    2013-09-01

    Low-frequency repetitive transcranial magnetic stimulation (LF-rTMS) of the left temporo-parietal cortex (LTPC) has been proposed as a useful therapeutic method for auditory hallucinations (AHs). Stereotactic neuronavigation enables the magnetic coil to be targeted according to the individual parameters obtained from neuroimaging. Individualized rTMS neuronavigated according to 18-fluorodeoxyglucose positron emission tomography ((18)FDG PET) allows us to focus the coil explicitly on a given area with detected maxima of specific abnormalities, thus presuming a higher therapeutic effect of the method. The objective of this study is to test clinical efficacy of neuronavigated LF-rTMS administered according to the local maxima of (18)FDG PET uptake of LTPC and to compare it with treatment effects of standard and sham rTMS. In a double-blind, sham-controlled design, patients with AHs underwent a 10-day series of LF-rTMS using (1) (18)FDG PET-guided "neuronavigation," (2) "standard" anatomically guided positioning, and (3) sham coil. The effect of different rTMS conditions was assessed by the Auditory Hallucinations Rating Scale (AHRS) and the Positive and Negative Syndrome Scale (PANSS). Fifteen patients were randomized to a treatment sequence and ten of them completed all three treatment conditions. The intention-to-treat analysis of AHRS score change revealed superiority of the (18)FDG PET-guided rTMS over both the standard and the sham rTMS. The analyses of the PANSS scores failed to detect significant difference among the treatments. Our data showed acute efficacy of (18)FDG PET-guided rTMS in the treatment of AHs. Neuronavigated rTMS was found to be more effective than standard, anatomically guided rTMS. PMID:22983355

  16. Low Resolution Structural Studies Indicate that the Activator of Hsp90 ATPase 1 (Aha1) of Leishmania braziliensis Has an Elongated Shape Which Allows Its Interaction with Both N- and M-Domains of Hsp90

    PubMed Central

    Seraphim, Thiago V.; Alves, Marina M.; Silva, Indjara M.; Gomes, Francisco E. R.; Silva, Kelly P.; Murta, Silvane M. F.; Barbosa, Leandro R. S.; Borges, Júlio C.

    2013-01-01

    The Hsp90 molecular chaperone is essential for protein homeostasis and in the maturation of proteins involved with cell-cycle control. The low ATPase activity of Hsp90 is critical to drive its functional cycle, which is dependent on the Hsp90 cochaperones. The Activator of Hsp90 ATPase-1 (Aha1) is a protein formed by two domains, N- and C-terminal, that stimulates the Hsp90 ATPase activity by several folds. Although the relevance of Aha1 for Hsp90 functions has been proved, as well as its involvement in the desensitization to inhibitors of the Hsp90, the knowledge on its overall structure and behavior in solution is limited. In this work we present the functional and structural characterization of Leishmania braziliensis Aha1 (LbAha1). This protozoan is the causative agent of cutaneous and mucocutaneous leishmaniasis, a neglected disease. The recombinant LbAha1 behaves as an elongated monomer and is organized into two folded domains interconnected by a flexible linker. Functional experiments showed that LbAha1 interacts with L. braziliensis Hsp90 (LbHsp90) with micromolar dissociation constant in a stoichiometry of 2 LbAha1 to 1 LbHsp90 dimer and stimulates 10-fold the LbHsp90 ATPase activity showing positive cooperativity. Furthermore, the LbHsp90::LbAha1 complex is directed by enthalphy and opposed by entropy, probably due to the spatial freedom restrictions imposed by the proteins’ interactions. Small-angle X-ray scattering data allowed the reconstruction of low resolution models and rigid body simulations of LbAha1, indicating its mode of action on LbHsp90. Western blot experiments allowed Aha1 identification (as well as Hsp90) in three Leishmania species at two temperatures, suggesting that Aha1 is a cognate protein. All these data shed light on the LbAha1 mechanism of action, showing that it has structural dimensions and flexibility that allow interacting with both N-terminal and middle domains of the LbHsp90. PMID:23826147

  17. Magnetic resonance spectroscopy of the human brain

    NASA Astrophysics Data System (ADS)

    Strózik-Kotlorz, D.

    2014-01-01

    I give a brief description of the magnetic resonance spectroscopy (MRS) in the human brain examinations. MRS allows a noninvasive chemical analysis of the brain using a standard high field MR system. Nowadays, the dominant form of MR brain spectroscopy is proton spectroscopy. Two main techniques of MRS, which utilize the chemical shift of metabolites in the external magnetic field, are SVS (single voxel) and CSI (single slice). The major peaks in the spectrum of a normal brain include NAA, Cr, Cho and m-Ins, which are neuronal, energetic, membrane turnover and glial markers, respectively. In disease, two pathological metabolites can be found in the brain spectra: Lac, which is end product of anaerobic glycolysis and Lip, which is a marker of membrane breakdown, occurring in necrosis. The common way to analyze clinical spectra is to determine metabolite ratios, e.g. NAA/Cr, Cho/Cr, Cho/NAA. This analysis permits a safe and noninvasive examination of the brain tissue as each disease state has its own characteristic spectroscopic image. MRS is a valuable diagnostic tool in such clinical applications as detecting brain tumors and differentiating tumors from inflammatory and infectious processes. Proton MRS is also very helpful in diagnostic of ischemic lesions, Alzheimer's disease and hepatic encephalopathy. The MRS brain spectra should always be correlated with the Magnetic Resonance Imaging (MRI) results and alone cannot make neurological diagnosis.

  18. Telemetry standards

    NASA Astrophysics Data System (ADS)

    1986-05-01

    The Telemetry Group (TG) of the Range Commanders Council (RCC) has prepared this document to foster the compatibility of telemetry transmitting, receiving, and signal processing equipment at all of the Test and Evaluation (T&E) ranges under the cognizance of the RCC. The Range Commanders highly recommend that telemetry equipment operated at the T&E ranges and telemetry equipment used by the range personnel in programs that require test range support, conform to these standards. These standards do not necessarily define the existing capability of any test range, but constitute a guide for the orderly implementation and application of telemetry systems for both the ranges and range users. The scope of capabilities attainable with the utilization of these standards requires a careful consideration of trade-offs. Guidance concerning these trade-offs is provided in the text. These standards provide the necessary criteria on which to base equipment design and modification. The ultimate purpose is to ensure an efficient spectrum and an interference-free operation of the radio link for telemetry systems at the RCC member ranges. etry systems at the RCC member ranges.

  19. Pesticide Standards

    ERIC Educational Resources Information Center

    Shea, Kevin P.

    1976-01-01

    The Environmental Protection Agency chose the American Society of Testing and Materials to develop standardized guidelines for pesticide registration. Since the numbers and uses of pesticides is so wide, establishing ecological and public health guidelines may be difficult. Strong industry and government representation might also hamper the…

  20. Brain Computer Interfaces, a Review

    PubMed Central

    Nicolas-Alonso, Luis Fernando; Gomez-Gil, Jaime

    2012-01-01

    A brain-computer interface (BCI) is a hardware and software communications system that permits cerebral activity alone to control computers or external devices. The immediate goal of BCI research is to provide communications capabilities to severely disabled people who are totally paralyzed or ‘locked in’ by neurological neuromuscular disorders, such as amyotrophic lateral sclerosis, brain stem stroke, or spinal cord injury. Here, we review the state-of-the-art of BCIs, looking at the different steps that form a standard BCI: signal acquisition, preprocessing or signal enhancement, feature extraction, classification and the control interface. We discuss their advantages, drawbacks, and latest advances, and we survey the numerous technologies reported in the scientific literature to design each step of a BCI. First, the review examines the neuroimaging modalities used in the signal acquisition step, each of which monitors a different functional brain activity such as electrical, magnetic or metabolic activity. Second, the review discusses different electrophysiological control signals that determine user intentions, which can be detected in brain activity. Third, the review includes some techniques used in the signal enhancement step to deal with the artifacts in the control signals and improve the performance. Fourth, the review studies some mathematic algorithms used in the feature extraction and classification steps which translate the information in the control signals into commands that operate a computer or other device. Finally, the review provides an overview of various BCI applications that control a range of devices. PMID:22438708

  1. Interface standardization

    NASA Astrophysics Data System (ADS)

    Spencer, R.; Wong, V.

    1983-11-01

    Central-station applications create a large and attractive market for photovoltaics in the near future. However, some significant barriers lie between the industry of today and realization of that market. Manufacturing capacity and price are two principal impediments. The Utilities, which are the future system owners, are gaining experience with central-station PV power through the Sacramento Municipal Utility District, Hesperia and similar small central-station installations. SMUD has recognized that competition must be maintained to help reduce prices. So little standardization exists that the cost is driven upward to redefine mechanical and electrical interfaces for each vendor. New structues are required for each vendor and nonoptimum field geometries result from attempts to include more than one vendor in an array field. Standards at some hardware level are required.

  2. Interface standardization

    NASA Technical Reports Server (NTRS)

    Spencer, R.; Wong, V.

    1983-01-01

    Central-station applications create a large and attractive market for photovoltaics in the near future. However, some significant barriers lie between the industry of today and realization of that market. Manufacturing capacity and price are two principal impediments. The Utilities, which are the future system owners, are gaining experience with central-station PV power through the Sacramento Municipal Utility District, Hesperia and similar small central-station installations. SMUD has recognized that competition must be maintained to help reduce prices. So little standardization exists that the cost is driven upward to redefine mechanical and electrical interfaces for each vendor. New structues are required for each vendor and nonoptimum field geometries result from attempts to include more than one vendor in an array field. Standards at some hardware level are required.

  3. A brain MRI atlas of the common squirrel monkey, Saimiri sciureus

    NASA Astrophysics Data System (ADS)

    Gao, Yurui; Schilling, Kurt G.; Khare, Shweta P.; Panda, Swetasudha; Choe, Ann S.; Stepniewska, Iwona; Li, Xia; Ding, Zhoahua; Anderson, Adam; Landman, Bennett A.

    2014-03-01

    The common squirrel monkey, Saimiri sciureus, is a New World monkey with functional and microstructural organization of central nervous system similar to that of humans. It is one of the most commonly used South American primates in biomedical research. Unlike its Old World macaque cousins, no digital atlases have described the organization of the squirrel monkey brain. Here, we present a multi-modal magnetic resonance imaging (MRI) atlas constructed from the brain of an adult female squirrel monkey. In vivo MRI acquisitions include high resolution T2 structural imaging and low resolution diffusion tensor imaging. Ex vivo MRI acquisitions include high resolution T2 structural imaging and high resolution diffusion tensor imaging. Cortical regions were manually annotated on the co-registered volumes based on published histological sections.

  4. Understanding brain networks and brain organization

    PubMed Central

    Pessoa, Luiz

    2014-01-01

    What is the relationship between brain and behavior? The answer to this question necessitates characterizing the mapping between structure and function. The aim of this paper is to discuss broad issues surrounding the link between structure and function in the brain that will motivate a network perspective to understanding this question. As others in the past, I argue that a network perspective should supplant the common strategy of understanding the brain in terms of individual regions. Whereas this perspective is needed for a fuller characterization of the mind-brain, it should not be viewed as panacea. For one, the challenges posed by the many-to-many mapping between regions and functions is not dissolved by the network perspective. Although the problem is ameliorated, one should not anticipate a one-to-one mapping when the network approach is adopted. Furthermore, decomposition of the brain network in terms of meaningful clusters of regions, such as the ones generated by community-finding algorithms, does not by itself reveal “true” subnetworks. Given the hierarchical and multi-relational relationship between regions, multiple decompositions will offer different “slices” of a broader landscape of networks within the brain. Finally, I described how the function of brain regions can be characterized in a multidimensional manner via the idea of diversity profiles. The concept can also be used to describe the way different brain regions participate in networks. PMID:24819881

  5. Left Brain Systems and Right Brain Managers.

    ERIC Educational Resources Information Center

    Brown, Jerry W.; Service, Allan L.

    1980-01-01

    Shortcomings of management information systems in managerial functions are often attributed to differences between "left brain" activities performed by machines and "right brain" activities performed in decision making. It is argued that academic management information systems should incorporate and recognize both kinds of activity. (MSE)

  6. Understanding brain networks and brain organization

    NASA Astrophysics Data System (ADS)

    Pessoa, Luiz

    2014-09-01

    What is the relationship between brain and behavior? The answer to this question necessitates characterizing the mapping between structure and function. The aim of this paper is to discuss broad issues surrounding the link between structure and function in the brain that will motivate a network perspective to understanding this question. However, as others in the past, I argue that a network perspective should supplant the common strategy of understanding the brain in terms of individual regions. Whereas this perspective is needed for a fuller characterization of the mind-brain, it should not be viewed as panacea. For one, the challenges posed by the many-to-many mapping between regions and functions is not dissolved by the network perspective. Although the problem is ameliorated, one should not anticipate a one-to-one mapping when the network approach is adopted. Furthermore, decomposition of the brain network in terms of meaningful clusters of regions, such as the ones generated by community-finding algorithms, does not by itself reveal "true" subnetworks. Given the hierarchical and multi-relational relationship between regions, multiple decompositions will offer different "slices" of a broader landscape of networks within the brain. Finally, I described how the function of brain regions can be characterized in a multidimensional manner via the idea of diversity profiles. The concept can also be used to describe the way different brain regions participate in networks.

  7. Brain glycogen supercompensation following exhaustive exercise.

    PubMed

    Matsui, Takashi; Ishikawa, Taro; Ito, Hitoshi; Okamoto, Masahiro; Inoue, Koshiro; Lee, Min-Chul; Fujikawa, Takahiko; Ichitani, Yukio; Kawanaka, Kentaro; Soya, Hideaki

    2012-02-01

    Brain glycogen localized in astrocytes, a critical energy source for neurons, decreases during prolonged exhaustive exercise with hypoglycaemia. However, it is uncertain whether exhaustive exercise induces glycogen supercompensation in the brain as in skeletal muscle. To explore this question, we exercised adult male rats to exhaustion at moderate intensity (20 m min(-1)) by treadmill, and quantified glycogen levels in several brain loci and skeletal muscles using a high-power (10 kW) microwave irradiation method as a gold standard. Skeletal muscle glycogen was depleted by 82-90% with exhaustive exercise, and supercompensated by 43-46% at 24 h after exercise. Brain glycogen levels decreased by 50-64% with exhaustive exercise, and supercompensated by 29-63% (whole brain 46%, cortex 60%, hippocampus 33%, hypothalamus 29%, cerebellum 63% and brainstem 49%) at 6 h after exercise. The brain glycogen supercompensation rates after exercise positively correlated with their decrease rates during exercise. We also observed that cortical and hippocampal glycogen supercompensation were sustained until 24 h after exercise (long-lasting supercompensation), and their basal glycogen levels increased with 4 weeks of exercise training (60 min day(-1) at 20 m min(-1)). These results support the hypothesis that, like the effect in skeletal muscles, glycogen supercompensation also occurs in the brain following exhaustive exercise, and the extent of supercompensation is dependent on that of glycogen decrease during exercise across brain regions. However, supercompensation in the brain preceded that of skeletal muscles. Further, the long-lasting supercompensation of the cortex and hippocampus is probably a prerequisite for their training adaptation (increased basal levels), probably to meet the increased energy demands of the brain in exercising animals. PMID:22063629

  8. Towards an artificial brain.

    PubMed

    Conrad, M; Kampfner, R R; Kirby, K G; Rizki, E N; Schleis, G; Smalz, R; Trenary, R

    1989-01-01

    Three components of a brain model operating on neuromolecular computing principles are described. The first component comprises neurons whose input-output behavior is controlled by significant internal dynamics. Models of discrete enzymatic neurons, reaction-diffusion neurons operating on the basis of the cyclic nucleotide cascade, and neurons controlled by cytoskeletal dynamics are described. The second component of the model is an evolutionary learning algorithm which is used to mold the behavior of enzyme-driven neurons or small networks of these neurons for specific function, usually pattern recognition or target seeking tasks. The evolutionary learning algorithm may be interpreted either as representing the mechanism of variation and natural selection acting on a phylogenetic time scale, or as a conceivable ontogenetic adaptation mechanism. The third component of the model is a memory manipulation scheme, called the reference neuron scheme. In principle it is capable of orchestrating a repertoire of enzyme-driven neurons for coherent function. The existing implementations, however, utilize simple neurons without internal dynamics. Spatial navigation and simple game playing (using tic-tac-toe) provide the task environments that have been used to study the properties of the reference neuron model. A memory-based evolutionary learning algorithm has been developed that can assign credit to the individual neurons in a network. It has been run on standard benchmark tasks, and appears to be quite effective both for conventional neural nets and for networks of discrete enzymatic neurons. The models have the character of artificial worlds in that they map the hierarchy of processes in the brain (at the molecular, neuronal, and network levels), provide a task environment, and use this relatively self-contained setup to develop and evaluate learning and adaptation algorithms. PMID:2627565

  9. NONINVASIVE BRAIN STIMULATION IN TRAUMATIC BRAIN INJURY

    PubMed Central

    Demirtas-Tatlidede, Asli; Vahabzadeh-Hagh, Andrew M.; Bernabeu, Montserrat; Tormos, Jose M.; Pascual-Leone, Alvaro

    2012-01-01

    Brain stimulation techniques have evolved in the last few decades with more novel methods capable of painless, noninvasive brain stimulation. While the number of clinical trials employing noninvasive brain stimulation continues to increase in a variety of medication-resistant neurological and psychiatric diseases, studies evaluating their diagnostic and therapeutic potential in traumatic brain injury (TBI) are largely lacking. This review introduces different techniques of noninvasive brain stimulation, which may find potential use in TBI. We cover transcranial magnetic stimulation (TMS), transcranial direct current stimulation (tDCS), low-level laser therapy (LLLT) and transcranial doppler sonography (TCD) techniques. We provide a brief overview of studies to date, discuss possible mechanisms of action, and raise a number of considerations when thinking about translating these methods to clinical use. PMID:21691215

  10. Left Brain, Right Brain: Facts and Fantasies

    PubMed Central

    Corballis, Michael C.

    2014-01-01

    Summary Handedness and brain asymmetry are widely regarded as unique to humans, and associated with complementary functions such as a left-brain specialization for language and logic and a right-brain specialization for creativity and intuition. In fact, asymmetries are widespread among animals, and support the gradual evolution of asymmetrical functions such as language and tool use. Handedness and brain asymmetry are inborn and under partial genetic control, although the gene or genes responsible are not well established. Cognitive and emotional difficulties are sometimes associated with departures from the “norm” of right-handedness and left-brain language dominance, more often with the absence of these asymmetries than their reversal. PMID:24465175

  11. Modulating Brain Oscillations to Drive Brain Function

    PubMed Central

    Thut, Gregor

    2014-01-01

    Do neuronal oscillations play a causal role in brain function? In a study in this issue of PLOS Biology, Helfrich and colleagues address this long-standing question by attempting to drive brain oscillations using transcranial electrical current stimulation. Remarkably, they were able to manipulate visual perception by forcing brain oscillations of the left and right visual hemispheres into synchrony using oscillatory currents over both hemispheres. Under this condition, human observers more often perceived an inherently ambiguous visual stimulus in one of its perceptual instantiations. These findings shed light on the mechanisms underlying neuronal computation. They show that it is the neuronal oscillations that drive the visual experience, not the experience driving the oscillations. And they indicate that synchronized oscillatory activity groups brain areas into functional networks. This points to new ways for controlled experimental and possibly also clinical interventions for the study and modulation of brain oscillations and associated functions. PMID:25549340

  12. Metastatic brain tumor

    MedlinePLUS

    ... on the location of the tumor in the brain, the type of tissue involved, the original location of the ... symptoms vary. The symptoms commonly seen with most types of metastatic brain tumor are those caused by increased pressure in ...

  13. Childhood Brain Tumors

    MedlinePLUS

    Brain tumors are abnormal growths inside the skull. They are among the most common types of childhood ... still be serious. Malignant tumors are cancerous. Childhood brain and spinal cord tumors can cause headaches and ...

  14. Brain aneurysm repair

    MedlinePLUS

    ... aneurysm repair; Dissecting aneurysm repair; Endovascular aneurysm repair - brain; Subarachnoid hemorrhage - aneurysm ... Your scalp, skull, and the coverings of the brain are opened. A metal clip is placed at ...

  15. Children's Brain Tumor Foundation

    MedlinePLUS

    ... CBTF Justin's Hope Fund Grant Recipients Grants Children’s Brain Tumor Foundation, A non-profit organization, was founded ... and the long term outlook for children with brain and spinal cord tumors through research, support, education, ...

  16. Pediatric Brain Tumor Foundation

    MedlinePLUS

    ... child's treatment. LEARN MORE More children die of brain tumors than any other cancer, so more research ... it up with Trey Canard Read more >> Pediatric Brain Tumor Foundation 302 Ridgefield Court, Asheville, NC 28806 ...

  17. Brain Basics: Preventing Stroke

    MedlinePLUS

    ... free mailed brochure Cómo Prevenir un Accidente Cerebrovascular Brain Basics: Preventing Stroke Request free mailed brochure Table ... Americans are protecting their most important asset—their brain. Are you? Stroke ranks as the fourth leading ...

  18. Traumatic Brain Injury (TBI)

    MedlinePLUS

    ... Research Information Clinical Trials Resources and Publications Traumatic Brain Injury (TBI): Condition Information Skip sharing on social ... external force that affects the functioning of the brain. It can be caused by a bump or ...

  19. Genetic Brain Disorders

    MedlinePLUS

    A genetic brain disorder is caused by a variation or a mutation in a gene. A variation is a different form ... mutation is a change in a gene. Genetic brain disorders affect the development and function of the ...

  20. Anatomy of the Brain

    MedlinePLUS

    ... as how we function in our environment. The diagrams below show brain anatomy, or the various parts ... and spine, as well as how they work, will help you understand the symptoms of brain tumors, how ...

  1. Aneurysm in the brain

    MedlinePLUS

    ... aneurysm occurs in a blood vessel of the brain, it is called a cerebral aneurysm. ... Aneurysms in the brain occur when there is a weakened area in the wall of a blood vessel. An aneurysm may be present ...

  2. Brain aneurysm repair - discharge

    MedlinePLUS

    You had a brain aneurysm. An aneurysm is a weak area in the wall of a blood vessel that bulges or balloons out. ... and cause bleeding along the surface of the brain. This is also called a subarachnoid hemorrhage. Sometimes ...

  3. NASA Robot Brain Surgeon

    NASA Technical Reports Server (NTRS)

    1997-01-01

    Mechanical Engineer Michael Guerrero works on the Robot Brain Surgeon testbed in the NeuroEngineering Group at the Ames Research Center, Moffett Field, California. Principal investigator Dr. Robert W. Mah states that potentially the simple robot will be able to feel brain structures better than any human surgeon, making slow, very precise movements during an operation. The brain surgery robot that may give surgeons finer control of surgical instruments during delicate brain operations is still under development.

  4. Neuromythology of Einstein's brain.

    PubMed

    Hines, Terence

    2014-07-01

    The idea that the brain of the great physicist Albert Einstein is different from "average" brains in both cellular structure and external shape is widespread. This belief is based on several studies examining Einstein's brain both histologically and morphologically. This paper reviews these studies and finds them wanting. Their results do not, in fact, provide support for the claim that the structure of Einstein's brain reflects his intellectual abilities. PMID:24836969

  5. [Brain imaging and schizophrenia].

    PubMed

    Martinot, J L; Dao-Castellana, M H

    1991-03-01

    Brain structures and brain function have been investigated by the new brain imaging techniques for more than ten years. In Psychiatry, these techniques could afford a new understanding of mental diseases. In schizophrenic patients, CAT scanner and RMI pointed out statistically significant ventricular enlargements which are presently considered as evidence for abnormalities in brain maturation. Functional imaging techniques reported metabolic dysfunctions in the cortical associative areas which are probably linked to the cognitive features of schizophrenics. PMID:2028204

  6. Twenty-first century brain banking: at the crossroads.

    PubMed

    Graeber, Manuel B

    2008-05-01

    Brain banks form an increasingly important resource for research. In view of declining autopsy rates, brain banks are also gaining importance for medical diagnostics, quality control and teaching. In the case of neurodegenerative diseases, brain banks have become drivers of discovery and are yielding invaluable taxonomic references for neuropathologists. This article provides comments on two recent landmark papers in the field (Bell JE et al. Acta Neuropathol 2008. doi:10.1007/s00401-008-0358-8; Vonsattel JP et al. Acta Neuropathol 2008. doi:10.1007/s00401-007-0311-9). Professionalisation of brain banking standards, ethical principles safeguarding the running of a brain bank and a proposed code of conduct for brain bank staff are outlined and discussed. Special emphasis is placed on the need to enable sustainability of the human brain tissue resource in the face of increased financial pressures on medical institutions and raised public expectations towards ethical human brain banking in a globalised economic environment. It is proposed that brain banks undergo rigorous international audit as a prerequisite for their registration with the relevant national neuropathological society. This promises to be an important safeguard so that proper standards can be assured when tissue is handed out to commercial companies. Honesty, accountability and complete transparency are mandatory to allow long-lasting success of the brain banking operation by guaranteeing that the best possible use is made of the tissue. Preferred access by private tissue users must be avoided and money must never be allowed to buy access to a brain bank. Since brain banks operate internationally, any mistake made may be felt around the globe and could endanger the public's willingness to donate brains for research. The much-needed increase in the number of control brain donations will only be achievable if broad-based support from the general public can be won and maintained. PMID:18347804

  7. Your Brain and Nervous System

    MedlinePLUS

    ... Skiing, Snowboarding, Skating Crushes What's a Booger? Your Brain & Nervous System KidsHealth > For Kids > Your Brain & Nervous ... The coolest wetsuit? Nope — he needs his cerebellum! Brain Stem Keeps You Breathing — and More Another brain ...

  8. Brain Aneurysm Statistics and Facts

    MedlinePLUS

    ... Sign-Up Contact Us Understanding Brain Aneurysm Basics Warning Signs/Symptoms Brain Aneurysm Statistics and Facts Seeking Medical Attention Pediatric Aneurysms Brain Aneurysm Causes and Risk Factors Family History Early Detection and Screening Unruptured Brain Aneurysms Subarachnoid Hemorrhage ...

  9. Extending the viability of acute brain slices

    PubMed Central

    Buskila, Yossi; Breen, Paul P.; Tapson, Jonathan; van Schaik, André; Barton, Matthew; Morley, John W.

    2014-01-01

    The lifespan of an acute brain slice is approximately 6–12?hours, limiting potential experimentation time. We have designed a new recovery incubation system capable of extending their lifespan to more than 36?hours. This system controls the temperature of the incubated artificial cerebral spinal fluid (aCSF) while continuously passing the fluid through a UVC filtration system and simultaneously monitoring temperature and pH. The combination of controlled temperature and UVC filtering maintains bacteria levels in the lag phase and leads to the dramatic extension of the brain slice lifespan. Brain slice viability was validated through electrophysiological recordings as well as live/dead cell assays. This system benefits researchers by monitoring incubation conditions and standardizing this artificial environment. It further provides viable tissue for two experimental days, reducing the time spent preparing brain slices and the number of animals required for research. PMID:24930889

  10. Brain and Spinal Tumors

    MedlinePLUS

    ... Awards Enhancing Diversity Find People About NINDS NINDS Brain and Spinal Tumors Information Page Synonym(s): Spinal Cord ... en Español Additional resources from MedlinePlus What are Brain and Spinal Tumors? Tumors of the brain and ...

  11. Brain Migration Revisited

    ERIC Educational Resources Information Center

    Vinokur, Annie

    2006-01-01

    The "brain drain/brain gain" debate has been going on for the past 40 years, with irresolvable theoretical disputes and unenforceable policy recommendations that economists commonly ascribe to the lack of reliable empirical data. The recent report of the World Bank, "International migration, remittances and the brain drain", documents the…

  12. Our Amazing Brains

    ERIC Educational Resources Information Center

    Bath, Howard

    2005-01-01

    This article begins a regular series on how brain research can help us understand young people and ourselves as well. The intent is to alert the reader to important information from recent research on the brain. This initial installment explores the concept of the triune brain, a term coined by neuroscientist Paul MacLean. This refers to three…

  13. Brain and Language.

    ERIC Educational Resources Information Center

    Damasio, Antonio R., Damasio, Hanna

    1992-01-01

    Discusses the advances made in understanding the brain structures responsible for language. Presents findings made using magnetic resonance imaging (MRI) and positron emission tomographic (PET) scans to study brain activity. These findings map the structures in the brain that manipulate concepts and those that turn concepts into words. (MCO)

  14. Brain Research and Learning.

    ERIC Educational Resources Information Center

    Claycomb, Mary

    Current research on brain activity has many implications for educators. The triune brain concept and the left and right hemisphere concepts are among the many complex theories evolving from experimentation and observation. The triune brain concept suggests that the human forebrain has expanded while retaining three structurally unique formations…

  15. Our Amazing Brains

    ERIC Educational Resources Information Center

    Bath, Howard

    2005-01-01

    This article begins a regular series on how brain research can help us understand young people and ourselves as well. The intent is to alert the reader to important information from recent research on the brain. This initial installment explores the concept of the triune brain, a term coined by neuroscientist Paul MacLean. This refers to three…

  16. Brain Migration Revisited

    ERIC Educational Resources Information Center

    Vinokur, Annie

    2006-01-01

    The "brain drain/brain gain" debate has been going on for the past 40 years, with irresolvable theoretical disputes and unenforceable policy recommendations that economists commonly ascribe to the lack of reliable empirical data. The recent report of the World Bank, "International migration, remittances and the brain drain", documents the…

  17. Build-a-brain.

    PubMed

    Chambers, Stuart M; Tchieu, Jason; Studer, Lorenz

    2013-10-01

    A major barrier in understanding nervous system development is modeling the cellular interactions that form the human brain. Recently, in the journal Nature, Lancaster et al. (2013) established a protocol for culturing pluripotent stem cell (PSC)-derived "cerebral organoids" that mimics the developing human brain's cellular organization, segregates into distinct brain regions, and models microcephaly. PMID:24094317

  18. Aligning brains and minds

    PubMed Central

    Tong, Frank

    2012-01-01

    In this issue of Neuron, Haxby and colleagues describe a new method for aligning functional brain activity patterns across participants. Their study demonstrates that objects are similarly represented across different brains, allowing for reliable classification of one person’s brain activity based on another’s. PMID:22017984

  19. Screening for Intermediately Vancomycin-Susceptible and Vancomycin-Heteroresistant Staphylococcus aureus by Use of Vancomycin-Supplemented Brain Heart Infusion Agar Biplates: Defining Growth Interpretation Criteria Based on Gold Standard Confirmation.

    PubMed

    Khatib, Riad; Riederer, Kathleen; Sharma, Mamta; Shemes, Stephen; Iyer, Sugantha P; Szpunar, Susan

    2015-11-01

    BHI agars supplemented with vancomycin 4 (BHI-V4) and 3 (BHI-V3) mg/liter have been proposed for screening vancomycin intermediately susceptible Staphylococcus aureus (VISA) and heteroresistant (hVISA) phenotypes, respectively, but growth interpretation criteria have not been established. We reviewed the growth results (CFU) during population analysis profile-area under the curve (PAP-AUC) of consecutive methicillin-resistant Staphylococcus aureus (MRSA) blood isolates, which were saved intermittently between 1996 and 2012. CFU counts on BHI-V4 and BHI-V3 plates were stratified according to PAP-AUC interpretive criteria: <0.90 (susceptible [S-MRSA]), 0.90 to 1.3 (hVISA), and >1.3 (VISA). CFU cutoffs that best predict VISA and hVISA were determined with the use of receiver operating characteristic (ROC) curves. Mu3, Mu50, and methicillin-susceptible S. aureus (MSSA) controls were included. We also prospectively evaluated manufacturer-made BHI-V3/BHI-V4 biplates for screening of 2010-2012 isolates. The PAP-AUC of 616 clinical samples was consistent with S-MRSA, hVISA, and VISA in 550 (89.3%), 48 (7.8%), and 18 (2.9%) instances, respectively. For VISA screening on BHI-V4, a cutoff of 2 CFU/droplet provided 100% sensitivity and 97.7% specificity. To distinguish VISA from hVISA, a cutoff of 16 CFU provided 83.3% sensitivity and 94.7% specificity; the specificity was lowered to 89.5% with a 12-CFU cutoff. For detecting hVISA/VISA on BHI-V3, a 2-CFU/droplet cutoff provided 98.5% sensitivity and 93.8% specificity. These results suggest that 2-CFU/droplet cutoffs on BHI-V4 and BHI-V3 best approximate VISA and hVISA gold standard confirmation, respectively, with minimal overlap in samples with borderline PAP-AUC. Simultaneous screening for VISA/hVISA on manufacturer-made BHI-V4/BHI-V3 biplates is easy to standardize and may reduce the requirement for PAP-AUC confirmation. PMID:26311860

  20. Neuroradiology of the Brain.

    PubMed

    Yeager, Susan

    2016-03-01

    A variety of imaging modalities are currently used to evaluate the brain. Prior to the 1970s, neurologic imaging involved radiographs, invasive procedures for spinal and carotid artery air and contrast injection, and painful patient manipulation. The brain was considered inaccessible to imaging and referred to as "the dark continent." Since then, advances in neuroradiology have moved the brain from being a dark continent to evaluation techniques that illuminate brain contents and pathology. These advances enable quick acquisition of images for prompt diagnosis and treatment. This article reviews anatomy, diagnostic principles, and clinical application of brain imaging beyond plain radiographs. PMID:26873758

  1. Construction of brain atlases based on a multi-center MRI dataset of 2020 Chinese adults.

    PubMed

    Liang, Peipeng; Shi, Lin; Chen, Nan; Luo, Yishan; Wang, Xing; Liu, Kai; Mok, Vincent Ct; Chu, Winnie Cw; Wang, Defeng; Li, Kuncheng

    2015-01-01

    Despite the known morphological differences (e.g., brain shape and size) in the brains of populations of different origins (e.g., age and race), the Chinese brain atlas is less studied. In the current study, we developed a statistical brain atlas based on a multi-center high quality magnetic resonance imaging (MRI) dataset of 2020 Chinese adults (18-76 years old). We constructed 12 Chinese brain atlas from the age 20 year to the age 75 at a 5 years interval. New Chinese brain standard space, coordinates, and brain area labels were further defined. The new Chinese brain atlas was validated in brain registration and segmentation. It was found that, as contrast to the MNI152 template, the proposed Chinese atlas showed higher accuracy in hippocampus segmentation and relatively smaller shape deformations during registration. These results indicate that a population-specific time varying brain atlas may be more appropriate for studies involving Chinese populations. PMID:26678304

  2. Construction of brain atlases based on a multi-center MRI dataset of 2020 Chinese adults

    PubMed Central

    Liang, Peipeng; Shi, Lin; Chen, Nan; Luo, Yishan; Wang, Xing; Liu, Kai; Mok, Vincent CT; Chu, Winnie CW; Wang, Defeng; Li, Kuncheng

    2015-01-01

    Despite the known morphological differences (e.g., brain shape and size) in the brains of populations of different origins (e.g., age and race), the Chinese brain atlas is less studied. In the current study, we developed a statistical brain atlas based on a multi-center high quality magnetic resonance imaging (MRI) dataset of 2020 Chinese adults (18–76 years old). We constructed 12 Chinese brain atlas from the age 20 year to the age 75 at a 5 years interval. New Chinese brain standard space, coordinates, and brain area labels were further defined. The new Chinese brain atlas was validated in brain registration and segmentation. It was found that, as contrast to the MNI152 template, the proposed Chinese atlas showed higher accuracy in hippocampus segmentation and relatively smaller shape deformations during registration. These results indicate that a population-specific time varying brain atlas may be more appropriate for studies involving Chinese populations. PMID:26678304

  3. Standardization work

    NASA Astrophysics Data System (ADS)

    Malavallon, Olivier

    1995-04-01

    For several years now, the main civil aircraft manufacturers (Airbus and its partners, Boeing, Fokker, McDonnell Douglas) have been working jointly on the writing of technical recommendations and the drawing up of an international standard. This work concerns the evaluation of the processes and products used to strip aeronautical paint systems. This procedure was initiated on request from the main airlines. In effect, the airlines are faced with situations in which the financial and operational objectives are becoming increasingly important. The need was felt to rationalize and, if possible, harmonize the criteria and technical requirements of the various civil aircraft manufacturers in order to facilitate in-service maintenance of the fleets of airlines operating Airbus, Boeing, Douglas aircraft, etc.

  4. The beryllium "double standard" standard.

    PubMed

    Egilman, David S; Bagley, Sarah; Biklen, Molly; Golub, Alison Stern; Bohme, Susanna Rankin

    2003-01-01

    Brush Wellman, the world's leading producer and supplier of beryllium products, has systematically hidden cases of beryllium disease that occurred below the threshold limit value (TLV) and lied about the efficacy of the TLV in published papers, lectures, reports to government agencies, and instructional materials prepared for customers and workers. Hypocritically, Brush Wellman instituted a zero exposure standard for corporate executives while workers and customers were told the 2 microgram standard was "safe." Brush intentionally used its workers as "canaries for the plant," and referred to them as such. Internal documents and corporate depositions indicate that these actions were intentional and that the motive was money. Despite knowledge of the inadequacy of the TLV, Brush has successfully used it as a defense against lawsuits brought by injured workers and as a sales device to provide reassurance to customers. Brush's policy has reaped an untold number of victims and resulted in mass distribution of beryllium in consumer products. Such corporate malfeasance is perpetuated by the current market system, which is controlled by an organized oligopoly that creates an incentive for the neglect of worker health and safety in favor of externalizing costs to victimized workers, their families, and society at large. PMID:14758859

  5. Multiscale analysis of brain tumors in CT imagery

    NASA Astrophysics Data System (ADS)

    Lu, Yi; Harmon, Laurel A.

    1993-04-01

    The delineation of brain lesion boundaries in computerized tomography (CT) or magnetic resonance imaging (MRI) sequences is important in many medical research environments and clinical applications. For example, computer-aided neurosurgery requires the extraction of boundaries of lesions in a series of CT or MRI images in order to design the surgical trajectory and complete the surgical planning. Currently, in many clinical applications, the boundaries of lesions are traced manually. Manual methods are not only tedious but also subjective, leading to substantial inter- and intraobserver variability, and confusions between lesions and coexisting normal structures pose serious problems. Automatic detection of lesions is a nontrivial problem. Because of the low resolution, the border regions between lesions and normal tissues are typically of single-pixel width in CT images, and the intensity gradient at the lesion boundary varies considerably. These characteristics of lesions within CT images, in conjunction with the generally low signal-to-noise ratio of CT images, render simple boundary detection techniques inadequate. Recent work in the field of computer vision has shown multiscale analysis of objects in gray scale images to be effective in many applications. This paper describes and illustrates the application of multiscale morphological techniques to the delineation of brain tumors.

  6. Brain iron homeostasis.

    PubMed

    Moos, Torben

    2002-11-01

    Iron is essential for virtually all types of cells and organisms. The significance of the iron for brain function is reflected by the presence of receptors for transferrin on brain capillary endothelial cells. The transport of iron into the brain from the circulation is regulated so that the extraction of iron by brain capillary endothelial cells is low in iron-replete conditions and the reverse when the iron need of the brain is high as in conditions with iron deficiency and during development of the brain. Whereas there is good agreement that iron is taken up by means of receptor-mediated uptake of iron-transferrin at the brain barriers, there are contradictory views on how iron is transported further on from the brain barriers and into the brain extracellular space. The prevailing hypothesis for transport of iron across the BBB suggests a mechanism that involves detachment of iron from transferrin within barrier cells followed by recycling of apo-transferrin to blood plasma and release of iron as non-transferrin-bound iron into the brain interstitium from where the iron is taken up by neurons and glial cells. Another hypothesis claims that iron-transferrin is transported into the brain by means of transcytosis through the BBB. This thesis deals with the topic "brain iron homeostasis" defined as the attempts to maintain constant concentrations of iron in the brain internal environment via regulation of iron transport through brain barriers, cellular iron uptake by neurons and glia, and export of iron from brain to blood. The first part deals with transport of iron-transferrin complexes from blood to brain either by transport across the brain barriers or by uptake and retrograde axonal transport in motor neurons projecting beyond the blood-brain barrier. The transport of iron and transport into the brain was examined using radiolabeled iron-transferrin. Intravenous injection of [59Fe-125]transferrin led to an almost two-fold higher accumulation of 59Fe than of [125I]transferrin in the brain. Some of the 59Fe was detected in CSF in a fraction less than 30 kDa (III). It was estimated that the iron-binding capacity of transferrin in CSF was exceeded, suggesting that iron is transported into the brain in a quantity that exceeds that of transferrin. Accordingly, it was concluded that the paramount iron transport across the BBB is the result of receptor-mediated endocytosis of iron-containing transferrin by capillary endothelial cells, followed by recycling of transferrin to the blood and transport of non-transferrin-bound iron into the brain. It was found that retrograde axonal transport in a cranial motor nerve is age-dependent, varying from almost negligible in the neonatal brain to high in the adult brain. The principle sources of extracellular transferrin in the brain are hepatocytes, oligodendrocytes, and the choroid plexus. As the passage of liver-derived transferrin into the brain is restricted due to the BBB, other candidates for binding iron in the interstitium should be considered. In vitro studies have revealed secretion of transferrin from the choroid plexus and oligodendrocytes. The second part of the thesis encompasses the circulation of iron in the extracellular fluids of the brain, i.e. the brain interstitial fluid and the CSF. As the latter receives drainage from the interstitial fluid, the CSF of the ventricles can be considered a mixture of these fluids, which may allow for analysis of CSF in matters that relate to the brain interstitial fluid. As the choroid plexus is known to synthesize transferrin, a key question is whether transferrin of the CSF might play a role for iron homeostasis by diffusing from the ventricles and subarachnoid space to the brain interstitium. Intracerebroventricular injection of [59Fe125I]transferrin led to a higher accumulation of 59Fe than of [125I]transferrin in the brain. Except for uptake and axonal transport by certain neurons with access to the ventricular CSF, both iron and transferrin were, however, restricted to areas situated in close proximity to the ventricular and pial surfaces. In particular, transferrin injected into the ventricles was never observed in regions distant from the CSF. It was concluded that choroid plexus-derived transferrin is not likely to play a significant role for binding and transporting iron in the brain interstitium. Transferrin secretion from oligodendrocytes probably plays the key role in this process. In the third part of the thesis, the uptake of iron by neurons devoid of projections beyond the blood-brain barrier and glia is addressed. Given the fact that the demonstration of plasma proteins in brain sections can be hampered by several methodological factors, a mapping of the cellular distribution of transferrin in the brain was performed employing extensive use of tissue-processing and staining protocols. In order to aid in the understanding of cellular iron uptake in the intact brain, attempts were made to identify iron, transferrin, and transferrin receptors at the light microscopic level. Consistent with the widespread distribution of transferrin receptors in neurons, the ligand transferrin was also found in neurons throughout the CNS. When examined at high resolution, transferrin was found to be distributed to the cytoplasm of neurons, exhibiting a dotted appearance, which is probably consistent with a distribution in the endosomallysosomal system. In contrast to the consistent presence of transferrin receptors on neurons, it was not possible to detect transferrin receptors on glial cells. Related to these observations, the presence of non-transferrin-bound iron in the brain suggests that glial cells may take it up by a mechanism that does not involve the transferrin receptor. The widespread distribution of ferritin in glial cells clearly indicates that the glial cells acquire iron. Dietary iron-overload did not change the distribution of transferrin receptors or ferritin in the brain. By contrast, iron deficiency altered the cellular content of these proteins so that transferrin receptors were higher and ferritin lower. The transport of iron from brain to blood was addressed in the last part of the thesis. It was found that in the case of iron and transferrin, there is no evidence showing other significant routes of transport from the brain extracellular fluid into the blood than drainage to the ventricular system followed by export to the blood via the arachnoid villi. The turnover of transferrin in the CSF was found to be very high. For reasons mentioned above, transferrin of the CSF is of little significance for transport and cellular delivery of iron to transferrin receptor-expressing neurons. Instead, transferrin of the CSF probably plays a significant role for neutralization and export to the blood of metals, including iron. Once appearing in blood, transferrin of the CSF was degraded at the same rate as intravenously injected transferrin, which indicates that the transferrin of CSF is not altered to an extent that changes its catabolism during the passage from CSF to blood plasma. The metabolism of iron in the developing brain was found to differ markedly when compared to that of the adult brain. A developing regulated transfer of iron to the brain was reflected morphologically by a higher content of transferrin receptors and non-heme iron in endothelial cells of the developing rat brain than in the adult. Neurons had a very low level of transferrin receptors. After about 20 days of age, iron transport into the brain decreased rapidly, and transferrin receptors appeared on neurons. Iron and transferrin injected into the ventricular system of the developing brain were much more widely distributed in the brain parenchyma than in the adult brain. This high accumulation of substances injected into the ventricles in young animals is probably due to the lower rate of production and turnover of CSF, which will increase the time available for diffusion of proteins into the brain parenchyma, thus giving neurons of the developing brain the opportunity to take up transferrin originating from the CSF. PMID:12553165

  7. Robotic multimodality stereotactic brain tissue identification: work in progress

    NASA Technical Reports Server (NTRS)

    Andrews, R.; Mah, R.; Galvagni, A.; Guerrero, M.; Papasin, R.; Wallace, M.; Winters, J.

    1997-01-01

    Real-time identification of tissue would improve procedures such as stereotactic brain biopsy (SBX), functional and implantation neurosurgery, and brain tumor excision. To standard SBX equipment has been added: (1) computer-controlled stepper motors to drive the biopsy needle/probe precisely; (2) multiple microprobes to track tissue density, detect blood vessels and changes in blood flow, and distinguish the various tissues being penetrated; (3) neural net learning programs to allow real-time comparisons of current data with a normative data bank; (4) three-dimensional graphic displays to follow the probe as it traverses brain tissue. The probe can differentiate substances such as pig brain, differing consistencies of the 'brain-like' foodstuff tofu, and gels made to simulate brain, as well as detect blood vessels imbedded in these substances. Multimodality probes should improve the safety, efficacy, and diagnostic accuracy of SBX and other neurosurgical procedures.

  8. Robotic multimodality stereotactic brain tissue identification: work in progress.

    PubMed

    Andrews, R; Mah, R; Galvagni, A; Guerrero, M; Papasin, R; Wallace, M; Winters, J

    1997-01-01

    Real-time identification of tissue would improve procedures such as stereotactic brain biopsy (SBX), functional and implantation neurosurgery, and brain tumor excision. To standard SBX equipment has been added: (1) computer-controlled stepper motors to drive the biopsy needle/probe precisely; (2) multiple microprobes to track tissue density, detect blood vessels and changes in blood flow, and distinguish the various tissues being penetrated; (3) neural net learning programs to allow real-time comparisons of current data with a normative data bank; (4) three-dimensional graphic displays to follow the probe as it traverses brain tissue. The probe can differentiate substances such as pig brain, differing consistencies of the 'brain-like' foodstuff tofu, and gels made to simulate brain, as well as detect blood vessels imbedded in these substances. Multimodality probes should improve the safety, efficacy, and diagnostic accuracy of SBX and other neurosurgical procedures. PMID:9711699

  9. An adaptive brain actuated system for augmenting rehabilitation

    PubMed Central

    Roset, Scott A.; Gant, Katie; Prasad, Abhishek; Sanchez, Justin C.

    2014-01-01

    For people living with paralysis, restoration of hand function remains the top priority because it leads to independence and improvement in quality of life. In approaches to restore hand and arm function, a goal is to better engage voluntary control and counteract maladaptive brain reorganization that results from non-use. Standard rehabilitation augmented with developments from the study of brain-computer interfaces could provide a combined therapy approach for motor cortex rehabilitation and to alleviate motor impairments. In this paper, an adaptive brain-computer interface system intended for application to control a functional electrical stimulation (FES) device is developed as an experimental test bed for augmenting rehabilitation with a brain-computer interface. The system's performance is improved throughout rehabilitation by passive user feedback and reinforcement learning. By continuously adapting to the user's brain activity, similar adaptive systems could be used to support clinical brain-computer interface neurorehabilitation over multiple days. PMID:25565945

  10. Clinical Brain Death with False Positive Radionuclide Cerebral Perfusion Scans

    PubMed Central

    Venkatram, Sindhaghatta; Bughio, Sara; Diaz-Fuentes, Gilda

    2015-01-01

    Practice guidelines from the American Academy of Neurology for the determination of brain death in adults define brain death as “the irreversible loss of function of the brain, including the brainstem.” Neurological determination of brain death is primarily based on clinical examination; if clinical criteria are met, a definitive confirmatory test is indicated. The apnea test remains the gold standard for confirmation. In patients with factors that confound the clinical determination or when apnea tests cannot safely be performed, an ancillary test is required to confirm brain death. Confirmatory ancillary tests for brain death include (a) tests of electrical activity (electroencephalography (EEG) and somatosensory evoked potentials) and (b) radiologic examinations of blood flow (contrast angiography, transcranial Doppler ultrasound (TCD), and radionuclide methods). Of these, however, radionuclide studies are used most commonly. Here we present data from two patients with a false positive Radionuclide Cerebral Perfusion Scan (RCPS). PMID:26167307

  11. The blue brain project.

    PubMed

    Markram, Henry

    2006-02-01

    IBM's Blue Gene supercomputer allows a quantum leap in the level of detail at which the brain can be modelled. I argue that the time is right to begin assimilating the wealth of data that has been accumulated over the past century and start building biologically accurate models of the brain from first principles to aid our understanding of brain function and dysfunction. PMID:16429124

  12. Neuromodulation of Brain States

    PubMed Central

    Lee, Seung-Hee; Dan, Yang

    2013-01-01

    Switches between different behavioral states of the animal are associated with prominent changes in global brain activity, between sleep and wakefulness or from inattentive to vigilant states. What mechanisms control brain states, and what are the functions of the different states? Here we summarize current understanding of the key neural circuits involved in regulating brain states, with a particular emphasis on the subcortical neuromodulatory systems. At the functional level, arousal and attention can greatly enhance sensory processing, whereas sleep and quiet wakefulness may facilitate learning and memory. Several new techniques developed over the past decade promise great advances in our understanding of the neural control and function of different brain states. PMID:23040816

  13. Brain tumor - children

    MedlinePLUS

    Glioblastoma multiforme - children; Ependymoma - children; Glioma - children; Brain stem glioma - children; Astrocytoma - children; Medulloblastoma - children; Germ cell tumors; Neuroglioma - children; Oligodendroglioma - ...

  14. Structural brain defects.

    PubMed

    Whitehead, Matthew T; Fricke, Stanley T; Gropman, Andrea L

    2015-06-01

    Up to 14% of patients with congenital metabolic disease may show structural brain abnormalities from perturbation of cell proliferation, migration, and/or organization. Most inborn errors of metabolism have a postnatal onset. Abnormalities from genetic disease processes have a prenatal onset. Energy impairment, substrate insufficiency, cell membrane receptor and cell signaling abnormalities, and toxic byproduct accumulation are associations between genetic disorders and structural brain anomalies. Collective imaging patterns of brain abnormalities can provide clues to the underlying etiology. We review selected metabolic diseases associated with brain malformations and highlight characteristic clinical and imaging manifestations that help narrow the differential diagnosis. PMID:26042908

  15. Consciousness, brain, neuroplasticity

    PubMed Central

    Askenasy, Jean; Lehmann, Joseph

    2013-01-01

    Subjectivity, intentionality, self-awareness and will are major components of consciousness in human beings. Changes in consciousness and its content following different brain processes and malfunction have long been studied. Cognitive sciences assume that brain activities have an infrastructure, but there is also evidence that consciousness itself may change this infrastructure. The two-way influence between brain and consciousness has been at the center of philosophy and less so, of science. This so-called bottom-up and top-down interrelationship is controversial and is the subject of our article. We would like to ask: how does it happen that consciousness may provoke structural changes in the brain? The living brain means continuous changes at the synaptic level with every new experience, with every new process of learning, memorizing or mastering new and existing skills. Synapses are generated and dissolved, while others are preserved, in an ever-changing process of so-called neuroplasticity. Ongoing processes of synaptic reinforcements and decay occur during wakefulness when consciousness is present, but also during sleep when it is mostly absent. We suggest that consciousness influences brain neuroplasticity both during wakefulness as well as sleep in a top-down way. This means that consciousness really activates synaptic flow and changes brain structures and functional organization. The dynamic impact of consciousness on brain never stops despite the relative stationary structure of the brain. Such a process can be a target for medical intervention, e.g., by cognitive training. PMID:23847580

  16. Brain Organization and Psychodynamics

    PubMed Central

    Peled, Avi; Geva, Amir B.

    1999-01-01

    Any attempt to link brain neural activity and psychodynamic concepts requires a tremendous conceptual leap. Such a leap may be facilitated if a common language between brain and mind can be devised. System theory proposes formulations that may aid in reconceptualizing psychodynamic descriptions in terms of neural organizations in the brain. Once adopted, these formulations can help to generate testable predictions about brain–psychodynamic relations and thus significantly affect the future of psychotherapy. (The Journal of Psychotherapy Practice and Research 1999; 8:24–39) PMID:9888105

  17. High Standards or a High Standard of Standardness?

    ERIC Educational Resources Information Center

    McWilliam, Erica

    2010-01-01

    This paper explores the difference between "high standards" and a "high standard of standardness" of professional service provision in teacher-librarianship. That is to say, it explores the difference between a demonstrated deep commitment to 21st century learning ("high standards") and demonstrated compliance with a pre-determined checklist of…

  18. Treatments for Brain Cancer Take Heavy Toll on the Brain

    MedlinePLUS

    ... Español You Are Here: Home ? Latest Health News ? Article URL of this page: https://www.nlm.nih.gov/medlineplus/news/fullstory_154467.html Treatments for Brain Cancer Take Heavy Toll on the Brain Brain ...

  19. Mg Isotopes of USGS Igneous Rock Standards

    NASA Astrophysics Data System (ADS)

    Huang, F.; Glessner, J. J.; Lundstrom, C. C.

    2008-12-01

    Magnesium has three stable isotopes, 24Mg, 25Mg, and 26Mg with abundances of 78.99%, 10.00%, and 11.01%, respectively. It is one of the most abundant elements in the crust and mantle. As advancements of analytical techniques using MC-ICP-MS have dramatically advanced our ability to measure isotope ratios of Mg with greater precision, Mg isotopes can now be applied to study a variety of fundamental geological processes, such as continental crust weathering, chemical diffusion, and chondrule formation. Therefore the need for well characterized Mg isotope ratios for geological materials is increasingly important. Routine measurement of readily-available USGS rock standards is a viable way for inter-lab comparison to show the quality of data. However, the Mg isotope data for USGS standards reported in the literature are limited and inconsistent. USGS standards reported by different MC-ICP-MS labs have a range of Mg isotopic data outside of the normal external error of 0.1‰ (2?). Mg isotopes of USGS igneous rock standards (dunite, DTS-1; basalts, BCR-1, BCR-2, BHVO-1; and andesite, AGV-1) were measured by a sample-standard bracketing method using a low resolution MC-ICP- MS (Nu-Plasma HR). The method has a large tolerance of matrix bias with Na/Mg and Al/Mg > 100% only changing the ?26Mg by less than 0.1‰. Dilution effects do not cause significant error (< 0.1‰) until the concentration difference between standard and sample is greater than 25%. The isobaric interference of CN+ on 26Mg was avoided by measuring Mg signal on the low mass shoulder. Only purified samples with excellent yields (>99.5%) and acceptable concentrations of matrix (mainly Na, Al, Ca, and Fe) are included in these results. Duplicate analyses of independently processed standards yielded the following results (?26MgDSM-3 (‰)): BCR-2 (-0.306±0.144, - 0.290±0.116, -0.283±0.048, -0.288±0.057), BCR-1 (-0.399±0.079, -0.346±0.046), AGV-1 (-0.295±0.110, -0.307±0.086, -0.339±0.068), BHVO-1 (-0.308±0.076, - 0.299±0.103), and DTS-1 (-0.299±0.163, -0.368±0.059). ?26MgDSM-3 of measured USGS standards are consistent within error (2?).

  20. Smart Moves: Powering up the Brain with Physical Activity

    ERIC Educational Resources Information Center

    Conyers, Marcus; Wilson, Donna

    2015-01-01

    The Common Core State Standards emphasize higher-order thinking, problem solving, and the creation, retention, and application of knowledge. Achieving these standards creates greater cognitive demands on students. Recent research suggests that active play and regular exercise have a positive effect on brain regions associated with executive…

  1. Smart Moves: Powering up the Brain with Physical Activity

    ERIC Educational Resources Information Center

    Conyers, Marcus; Wilson, Donna

    2015-01-01

    The Common Core State Standards emphasize higher-order thinking, problem solving, and the creation, retention, and application of knowledge. Achieving these standards creates greater cognitive demands on students. Recent research suggests that active play and regular exercise have a positive effect on brain regions associated with executive…

  2. Head, neck, and brain tumor embolization guidelines

    PubMed Central

    Duffis, E Jesus; Prestigiacomo, Charles Joseph; Abruzzo, Todd; Albuquerque, Felipe; Bulsara, Ketan R; Derdeyn, Colin P; Fraser, Justin F; Hirsch, Joshua A; Hussain, Muhammad Shazam; Do, Huy M; Jayaraman, Mahesh V; Meyers, Philip M; Narayanan, Sandra

    2012-01-01

    Background Management of vascular tumors of the head, neck, and brain is often complex and requires a multidisciplinary approach. Peri-operative embolization of vascular tumors may help to reduce intra-operative bleeding and operative times and have thus become an integral part of the management of these tumors. Advances in catheter and non-catheter based techniques in conjunction with the growing field of neurointerventional surgery is likely to expand the number of peri-operative embolizations performed. The goal of this article is to provide consensus reporting standards and guidelines for embolization treatment of vascular head, neck, and brain tumors. Summary This article was produced by a writing group comprised of members of the Society of Neurointerventional Surgery. A computerized literature search using the National Library of Medicine database (Pubmed) was conducted for relevant articles published between 1 January 1990 and 31 December 2010. The article summarizes the effectiveness and safety of peri-operative vascular tumor embolization. In addition, this document provides consensus definitions and reporting standards as well as guidelines not intended to represent the standard of care, but rather to provide uniformity in subsequent trials and studies involving embolization of vascular head and neck as well as brain tumors. Conclusions Peri-operative embolization of vascular head, neck, and brain tumors is an effective and safe adjuvant to surgical resection. Major complications reported in the literature are rare when these procedures are performed by operators with appropriate training and knowledge of the relevant vascular and surgical anatomy. These standards may help to standardize reporting and publication in future studies. PMID:22539531

  3. Drugs and the Brain.

    ERIC Educational Resources Information Center

    National Institutes of Health (DHHS), Bethesda, MD.

    This booklet explores various aspects of drug addiction, with a special focus on drugs' effects on the brain. A brief introduction presents information on the rampant use of drugs in society and elaborates the distinction between drug abuse and drug addiction. Next, a detailed analysis of the brain and its functions is given. Drugs target the more…

  4. Demystifying the Adolescent Brain

    ERIC Educational Resources Information Center

    Steinberg, Laurence

    2011-01-01

    Understanding the nature of brain development in adolescence helps explain why adolescents can vacillate so often between mature and immature behavior. Early and middle adolescence, in particular, are times of heightened vulnerability to risky and reckless behavior because the brain's reward center is easily aroused, but the systems that control…

  5. COPPER AND BRAIN FUNCTION

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Increasing evidence shows that brain development and function are impaired when the brain is deprived of copper either through dietary copper deficiency or through genetic defects in copper transport. A number of copper-dependent enzymes whose activities are lowered by copper deprivation form the ba...

  6. What a Brain!

    ERIC Educational Resources Information Center

    Love, Kim

    1997-01-01

    Outlines basic concepts about how the brain develops and considers how Head Start teachers and parents can take full advantage of the brain's multisensory learning approach to develop more effective ways to interact with children. Focuses on the critical developmental period for stimulating neurons and developing neural connections. Suggests…

  7. Feed Your Brain!

    ERIC Educational Resources Information Center

    Failmezger, Tammie L.

    2006-01-01

    Language arts teachers and library media specialists bear the responsibility of teaching students how to properly feed their brains. In this article, the author describes how she teaches her students to make wise choices when selecting books. Furthermore, she presents the "Brain Food Pyramid" model that looks similar to the food pyramid but it…

  8. Using Your Brain

    ERIC Educational Resources Information Center

    Ward, Hellen

    2011-01-01

    Many scientists have been fascinated by how the brain works, but much of what is known about the brain has been discovered within the last twenty years. In this article, the author explores how thinking and using one's mind are essential to understanding. She contends that children need to be in control of their learning; the adult's role is to…

  9. Demystifying the Adolescent Brain

    ERIC Educational Resources Information Center

    Steinberg, Laurence

    2011-01-01

    Understanding the nature of brain development in adolescence helps explain why adolescents can vacillate so often between mature and immature behavior. Early and middle adolescence, in particular, are times of heightened vulnerability to risky and reckless behavior because the brain's reward center is easily aroused, but the systems that control…

  10. The Resilient Brain

    ERIC Educational Resources Information Center

    Brendtro, Larry K.; Longhurst, James E.

    2005-01-01

    Brain research opens new frontiers in working with children and youth experiencing conflict in school and community. Blending this knowledge with resilience science offers a roadmap for reclaiming those identified as "at risk." This article applies findings from resilience research and recent brain research to identify strategies for reaching…

  11. Inside the Adolescent Brain

    ERIC Educational Resources Information Center

    Drury, Stacy S.

    2009-01-01

    Dr. Jay Giedd says that the main alterations in the adolescent brain are the inverted U-shaped developmental trajectories with late childhood/early teen peaks for gray matter volume among others. Giedd adds that the adolescent brain is vulnerable to substances that artificially modulate dopamine levels since its reward system is in a state of flux.

  12. Learning and the Brain.

    ERIC Educational Resources Information Center

    Fishback, Sarah Jane

    1999-01-01

    Reviews research on the brain and memory, emotions, aging, and learning. Outlines practice implications: connect new learning to personal experiences, make sure learners are paying attention, recognize the role of emotions, and be aware that stimulation influences the aging brain. (SK)

  13. Brain Pressure Monitoring

    NASA Technical Reports Server (NTRS)

    1977-01-01

    A transducer originally used to measure air pressure in aircraft wind tunnel tests is the basis for a development important in diagnosis and treatment of certain types of brain damage. A totally implantable device, tbe intracranial pressure monitor measures and reports brain pressure by telemetry.

  14. Using Your Brain

    ERIC Educational Resources Information Center

    Ward, Hellen

    2011-01-01

    Many scientists have been fascinated by how the brain works, but much of what is known about the brain has been discovered within the last twenty years. In this article, the author explores how thinking and using one's mind are essential to understanding. She contends that children need to be in control of their learning; the adult's role is to…

  15. Feed Your Brain!

    ERIC Educational Resources Information Center

    Failmezger, Tammie L.

    2006-01-01

    Language arts teachers and library media specialists bear the responsibility of teaching students how to properly feed their brains. In this article, the author describes how she teaches her students to make wise choices when selecting books. Furthermore, she presents the "Brain Food Pyramid" model that looks similar to the food pyramid but it…

  16. Imaging the Working Brain.

    ERIC Educational Resources Information Center

    Swithenby, S. J.

    1996-01-01

    Very sensitive SQUID (superconducting quantum interference device) detectors are used in the technique known as magnetoencephalography to provide dynamic images of the brain. This can help our fundamental understanding of the way the brain works and may be of particular use in treating disorders such as epilepsy. (Author/MKR)

  17. Brain Friendly School Libraries

    ERIC Educational Resources Information Center

    Sykes, Judith Anne

    2006-01-01

    This title gives concrete practical examples of how to align school library programs and instructional practice with the six key concepts of brain-compatible learning: increasing input to the brain; increasing experiential data; multiple source feedback; reducing threat; involving students in learning decision making; and interdisciplinary unit…

  18. Brain Friendly School Libraries

    ERIC Educational Resources Information Center

    Sykes, Judith Anne

    2006-01-01

    This title gives concrete practical examples of how to align school library programs and instructional practice with the six key concepts of brain-compatible learning: increasing input to the brain; increasing experiential data; multiple source feedback; reducing threat; involving students in learning decision making; and interdisciplinary unit…

  19. Brain imaging in psychiatry

    SciTech Connect

    Morihisa, J.M.

    1984-01-01

    This book contains the following five chapters: Positron Emission Tomography (PET) in Psychiatry; Regional Cerebral Blood Flow (CBF) in Psychiatry: Methodological Issues; Regional Cerebral Blood Flow in Psychiatry: Application to Clinical Research; Regional Cerebral Blood Flow in Psychiatry: The Resting and Activated Brains of Schizophrenic Patients; and Brain Electrical Activity Mapping (BEAM) in Psychiatry.

  20. The Emerging Scholarly Brain

    NASA Astrophysics Data System (ADS)

    Kurtz, Michael J.

    It is now a commonplace observation that human society is becoming a coherent super-organism, and that the information infrastructure forms its emerging brain. Perhaps, as the underlying technologies are likely to become billions of times more powerful than those we have today, we could say that we are now building the lizard brain for the future organism.

  1. Standards in neurosonology. Part I

    PubMed Central

    Tomczyk, Tomasz; Luchowski, Piotr; Kozera, Grzegorz; Ka?mierski, Rados?aw; Stelmasiak, Zbigniew

    2015-01-01

    The paper presents standards related to ultrasound imaging of the cerebral vasculature and structures. The aim of this paper is to standardize both the performance and description of ultrasound imaging of the extracranial and intracranial cerebral arteries as well as a study of a specific brain structure, i.e. substantia nigra hyperechogenicity. The following aspects are included in the description of standards for each ultrasonographic method: equipment requirements, patient preparation, study technique and documentation as well as the required elements of ultrasound description. Practical criteria for the diagnosis of certain pathologies in accordance with the latest literature were also presented. Furthermore, additional comments were included in some of the sections. Part I discusses standards for the performance, documentation and description of different ultrasound methods (Duplex, Doppler). Part II and III are devoted to standards for specific clinical situations (vasospasm, monitoring after the acute stage of stroke, detection of a right-toleft shunts, confirmation of the arrest of the cerebral circulation, an assessment of the functional efficiency of circle of Willis, an assessment of the cerebrovascular vasomotor reserve as well as the measurement of substantia nigra hyperechogenicity). PMID:26674617

  2. Standards in neurosonology. Part I.

    PubMed

    Wojczal, Joanna; Tomczyk, Tomasz; Luchowski, Piotr; Kozera, Grzegorz; Ka?mierski, Rados?aw; Stelmasiak, Zbigniew

    2015-09-01

    The paper presents standards related to ultrasound imaging of the cerebral vasculature and structures. The aim of this paper is to standardize both the performance and description of ultrasound imaging of the extracranial and intracranial cerebral arteries as well as a study of a specific brain structure, i.e. substantia nigra hyperechogenicity. The following aspects are included in the description of standards for each ultrasonographic method: equipment requirements, patient preparation, study technique and documentation as well as the required elements of ultrasound description. Practical criteria for the diagnosis of certain pathologies in accordance with the latest literature were also presented. Furthermore, additional comments were included in some of the sections. Part I discusses standards for the performance, documentation and description of different ultrasound methods (Duplex, Doppler). Part II and III are devoted to standards for specific clinical situations (vasospasm, monitoring after the acute stage of stroke, detection of a right-toleft shunts, confirmation of the arrest of the cerebral circulation, an assessment of the functional efficiency of circle of Willis, an assessment of the cerebrovascular vasomotor reserve as well as the measurement of substantia nigra hyperechogenicity). PMID:26674617

  3. Neurodegeneration with Brain Iron Accumulation

    MedlinePLUS

    ... Diversity Find People About NINDS NINDS Neurodegeneration with Brain Iron Accumulation Information Page Synonym(s): Hallervorden-Spatz Disease, ... done? Clinical Trials Organizations What is Neurodegeneration with Brain Iron Accumulation? Neurodegeneration with brain iron accumulation (NBIA) ...

  4. Primary lymphoma of the brain

    MedlinePLUS

    Brain lymphoma; Cerebral lymphoma; Primary lymphoma of the central nervous system; Lymphoma - brain ... The cause of primary brain lymphoma is not known. Patients who have a weakened immune system are at high risk of primary lymphoma of the ...

  5. Metabolic profiling of Alzheimer's disease brains

    NASA Astrophysics Data System (ADS)

    Inoue, Koichi; Tsutsui, Haruhito; Akatsu, Hiroyasu; Hashizume, Yoshio; Matsukawa, Noriyuki; Yamamoto, Takayuki; Toyo'Oka, Toshimasa

    2013-08-01

    Alzheimer's disease (AD) is an irreversible, progressive brain disease and can be definitively diagnosed after death through an examination of senile plaques and neurofibrillary tangles in several brain regions. It is to be expected that changes in the concentration and/or localization of low-molecular-weight molecules are linked to the pathological changes that occur in AD, and determining their identity would provide valuable information regarding AD processes. Here, we propose definitive brain metabolic profiling using ultra-performance liquid chromatography coupled with electrospray time-of-flight mass spectrometry analysis. The acquired data were subjected to principal components analysis to differentiate the frontal and parietal lobes of the AD/Control groups. Significant differences in the levels of spermine and spermidine were identified using S-plot, mass spectra, databases and standards. Based on the investigation of the polyamine metabolite pathway, these data establish that the downstream metabolites of ornithine are increased, potentially implicating ornithine decarboxylase activity in AD pathology.

  6. Modern Brain Tumor Imaging

    PubMed Central

    Barajas, Ramon F.; Cha, Soonmee

    2015-01-01

    The imaging and clinical management of patients with brain tumor continue to evolve over time and now heavily rely on physiologic imaging in addition to high-resolution structural imaging. Imaging remains a powerful noninvasive tool to positively impact the management of patients with brain tumor. This article provides an overview of the current state-of-the art clinical brain tumor imaging. In this review, we discuss general magnetic resonance (MR) imaging methods and their application to the diagnosis of, treatment planning and navigation, and disease monitoring in patients with brain tumor. We review the strengths, limitations, and pitfalls of structural imaging, diffusion-weighted imaging techniques, MR spectroscopy, perfusion imaging, positron emission tomography/MR, and functional imaging. Overall this review provides a basis for understudying the role of modern imaging in the care of brain tumor patients. PMID:25977902

  7. Coping changes the brain

    PubMed Central

    Nechvatal, Jordan M.; Lyons, David M.

    2013-01-01

    One of the earliest and most consistent findings in behavioral neuroscience research is that learning changes the brain. Here we consider how learning as an aspect of coping in the context of stress exposure induces neuroadaptations that enhance emotion regulation and resilience. A systematic review of the literature identified 15 brain imaging studies in which humans with specific phobias or post-traumatic stress disorder (PTSD) were randomized to stress exposure therapies that diminished subsequent indications of anxiety. Most of these studies focused on functional changes in the amygdala and anterior corticolimbic brain circuits that control cognitive, motivational, and emotional aspects of physiology and behavior. Corresponding structural brain changes and the timing, frequency, and duration of stress exposure required to modify brain functions remain to be elucidated in future research. These studies will advance our understanding of coping as a learning process and provide mechanistic insights for the development of new interventions that promote stress coping skills. PMID:23439935

  8. Brain Dynamics Promotes Function

    NASA Astrophysics Data System (ADS)

    Lourenço, Carlos

    Dynamical structure in the brain promotes biological function. Natural scientists look for correlations between measured electrical signals and behavior or mental states. Computational scientists have new opportunities to receive ’algorithmic’ inspiration from brain processes and propose computational paradigms. Thus a tradition which dates back to the 1940s with neural nets research is renewed. Real processes in the brain are ’complex’ and withstand trivial descriptions. However, dynamical complexity need not be at odds with a computational description of the phenomena and with the inspiration for algorithms that actually compute something in an engineering sense. We engage this complexity from a computational viewpoint, not excluding dynamical regimes that a number of authors are willing to label as chaos. The key question is: what may we be missing computation-wise if we overlook brain dynamics? At this point in brain research, we are happy if we can at least provide a partial answer.

  9. Intraoperative virtual brain counseling

    NASA Astrophysics Data System (ADS)

    Jiang, Zhaowei; Grosky, William I.; Zamorano, Lucia J.; Muzik, Otto; Diaz, Fernando

    1997-06-01

    Our objective is to offer online real-tim e intelligent guidance to the neurosurgeon. Different from traditional image-guidance technologies that offer intra-operative visualization of medical images or atlas images, virtual brain counseling goes one step further. It can distinguish related brain structures and provide information about them intra-operatively. Virtual brain counseling is the foundation for surgical planing optimization and on-line surgical reference. It can provide a warning system that alerts the neurosurgeon if the chosen trajectory will pass through eloquent brain areas. In order to fulfill this objective, tracking techniques are involved for intra- operativity. Most importantly, a 3D virtual brian environment, different from traditional 3D digitized atlases, is an object-oriented model of the brain that stores information about different brain structures together with their elated information. An object-oriented hierarchical hyper-voxel space (HHVS) is introduced to integrate anatomical and functional structures. Spatial queries based on position of interest, line segment of interest, and volume of interest are introduced in this paper. The virtual brain environment is integrated with existing surgical pre-planning and intra-operative tracking systems to provide information for planning optimization and on-line surgical guidance. The neurosurgeon is alerted automatically if the planned treatment affects any critical structures. Architectures such as HHVS and algorithms, such as spatial querying, normalizing, and warping are presented in the paper. A prototype has shown that the virtual brain is intuitive in its hierarchical 3D appearance. It also showed that HHVS, as the key structure for virtual brain counseling, efficiently integrates multi-scale brain structures based on their spatial relationships.This is a promising development for optimization of treatment plans and online surgical intelligent guidance.

  10. Quantitative EEG and neurofeedback in children and adolescents: anxiety disorders, depressive disorders, comorbid addiction and attention-deficit/hyperactivity disorder, and brain injury.

    PubMed

    Simkin, Deborah R; Thatcher, Robert W; Lubar, Joel

    2014-07-01

    This article explores the science surrounding neurofeedback. Both surface neurofeedback (using 2-4 electrodes) and newer interventions, such as real-time z-score neurofeedback (electroencephalogram [EEG] biofeedback) and low-resolution electromagnetic tomography neurofeedback, are reviewed. The limited literature on neurofeedback research in children and adolescents is discussed regarding treatment of anxiety, mood, addiction (with comorbid attention-deficit/hyperactivity disorder), and traumatic brain injury. Future potential applications, the use of quantitative EEG for determining which patients will be responsive to medications, the role of randomized controlled studies in neurofeedback research, and sensible clinical guidelines are considered. PMID:24975621

  11. Impact of the resolution of brain parcels on connectome-wide association studies in fMRI.

    PubMed

    Bellec, Pierre; Benhajali, Yassine; Carbonell, Felix; Dansereau, Christian; Albouy, Geneviève; Pelland, Maxime; Craddock, Cameron; Collignon, Oliver; Doyon, Julien; Stip, Emmanuel; Orban, Pierre

    2015-12-01

    A recent trend in functional magnetic resonance imaging is to test for association of clinical disorders with every possible connection between selected brain parcels. We investigated the impact of the resolution of functional brain parcels, ranging from large-scale networks to local regions, on a mass univariate general linear model (GLM) of connectomes. For each resolution taken independently, the Benjamini-Hochberg procedure controlled the false-discovery rate (FDR) at nominal level on realistic simulations. However, the FDR for tests pooled across all resolutions could be inflated compared to the FDR within resolution. This inflation was severe in the presence of no or weak effects, but became negligible for strong effects. We thus developed an omnibus test to establish the overall presence of true discoveries across all resolutions. Although not a guarantee to control the FDR across resolutions, the omnibus test may be used for descriptive analysis of the impact of resolution on a GLM analysis, in complement to a primary analysis at a predefined single resolution. On three real datasets with significant omnibus test (schizophrenia, congenital blindness, motor practice), markedly higher rate of discovery were obtained at low resolutions, below 50, in line with simulations showing increase in sensitivity at such resolutions. This increase in discovery rate came at the cost of a lower ability to localize effects, as low resolution parcels merged many different brain regions together. However, with 30 or more parcels, the statistical effect maps were biologically plausible and very consistent across resolutions. These results show that resolution is a key parameter for GLM-connectome analysis with FDR control, and that a functional brain parcellation with 30 to 50 parcels may lead to an accurate summary of full connectome effects with good sensitivity in many situations. PMID:26241681

  12. Radiation Injury to the Brain

    MedlinePLUS

    ... AVMs Radiosurgery Gamma Knife Linac Radiotherapy Overview Childhood Brain Tumors IMRT Radiation Therapy Radiation Injury Treatment Day Making a Decision Centers of Excellence Publications Definitions Q & A Brain ...

  13. [Epidemiology of brain metastases].

    PubMed

    Taillibert, S; Le Rhun, É

    2015-02-01

    The most frequent intracranial brain tumours are brain metastases. All types of cancer can develop brain metastases but two thirds of brain metastases occurring in adult patients are secondary to one of these three cancers: lung cancer, breast cancer and melanoma. In accordance with these data, this review is focusing on the epidemiology of these three types of cancer. We report here the incidence, risk factors, median time of brain metastases occurrence after diagnosis of the primary cancer, prognosis and median survival for these three types of cancer. We also discuss the clinical implications of these data. The second part of this review is focusing on the Graded Prognostic Assessment scores in all types of primary cancer with brain metastases, how they can be applied in clinical research for a better stratification of patients, and to some extent in clinical practice to guide decisions for personalized treatments. These scores provide a better understanding of the different profiles of clinical evolution that can be observed amongst patients suffering from brain metastases according to the type of primary cancer. We highlighted the most remarkable and useful clinical implications of these data. PMID:25636729

  14. Lutein and Brain Function

    PubMed Central

    Erdman, John W.; Smith, Joshua W.; Kuchan, Matthew J.; Mohn, Emily S.; Johnson, Elizabeth J.; Rubakhin, Stanislav S.; Wang, Lin; Sweedler, Jonathan V.; Neuringer, Martha

    2015-01-01

    Lutein is one of the most prevalent carotenoids in nature and in the human diet. Together with zeaxanthin, it is highly concentrated as macular pigment in the foveal retina of primates, attenuating blue light exposure, providing protection from photo-oxidation and enhancing visual performance. Recently, interest in lutein has expanded beyond the retina to its possible contributions to brain development and function. Only primates accumulate lutein within the brain, but little is known about its distribution or physiological role. Our team has begun to utilize the rhesus macaque (Macaca mulatta) model to study the uptake and bio-localization of lutein in the brain. Our overall goal has been to assess the association of lutein localization with brain function. In this review, we will first cover the evolution of the non-human primate model for lutein and brain studies, discuss prior association studies of lutein with retina and brain function, and review approaches that can be used to localize brain lutein. We also describe our approach to the biosynthesis of 13C-lutein, which will allow investigation of lutein flux, localization, metabolism and pharmacokinetics. Lastly, we describe potential future research opportunities. PMID:26566524

  15. Are there fetal stem cells in the maternal brain??

    PubMed Central

    Demirhan, Osman; Çekin, Necmi; Ta?temir, Deniz; Tunç, Erdal; Güzel, Ali ?rfan; Meral, Demet; Demirbek, Bülent

    2013-01-01

    Fetal cells can enter maternal blood during pregnancy but whether they can also cross the blood-brain barrier to enter the maternal brain remains poorly understood. Previous results suggest that fetal cells are summoned to repair damage to the mother's brain. If this is confirmed, it would open up new and safer avenues of treatment for brain damage caused by strokes and neural diseases. In this study, we aimed to investigate whether a baby's stem cells can enter the maternal brain during pregnancy. Deceased patients who had at least one male offspring and no history of abortion and blood transfusion were included in this study. DNA was extracted from brain tissue samples of deceased women using standard phenol-chloroform extraction and ethanol precipitation methods. Genomic DNA was screened by quantitative fluorescent-polymerase chain reaction amplification together with short tandem repeat markers specific to the Y chromosome, and 13, 18, 21 and X. Any foreign DNA residues that could be used to interpret the presence of fetal stem cells in the maternal brain were monitored. Results indicated that fetal stem cells can not cross the blood-brain barrier to enter the maternal brain. PMID:25206703

  16. Epidemiology and prognosis of brain metastases

    PubMed Central

    Stelzer, Keith J.

    2013-01-01

    A substantial, but uncertain, number of patients with cancer develop brain metastases. Risk of brain metastasis is recognized to vary with type of primary cancer. Within specific types of primary cancer, prognostic factors for development of brain metastases are being recognized. Recent data suggest that molecular biomarkers that relate to cellular function can predict risk of developing brain metastases. Such information could optimize surveillance standards and/or be used to select patients for preventive interventions. Though average survival for patients with brain metastases is typically less than 6 months, it is well-recognized that subgroups of patients have significant probability of longer survival. Multiple prognostic models have been proposed, validated, and compared without clearly demonstrating superiority of one model over another. However, some factors show consistency as predictive variables across models, and performance status is almost universally significant. Application of predictive models to specific treatments has been difficult. Tumor-specific prognostic models are evolving, and combinations of biological and clinical factors may be used to optimize models for particular primary tumor types. PMID:23717790

  17. Critical Illness Brain Injury.

    PubMed

    Girard, Timothy D; Dittus, Robert S; Ely, E Wesley

    2016-01-14

    A growing body of literature has shown that survivors of critical illness often struggle with cognitive impairment that persists months to years after hospital discharge. We describe the epidemiology of this form of cognitive impairment-which we refer to as critical illness brain injury-and review the history and maturation of the investigation of this previously unrecognized, yet common problem. We then review the characteristics of critical illness brain injury, which can vary in severity and typically affects multiple domains of cognition. Finally, we examine known risk factors for critical illness brain injury and, based on these data, suggest approaches to patient management. PMID:26768245

  18. Aldosterone in the brain

    PubMed Central

    Geerling, Joel C.; Loewy, Arthur D.

    2009-01-01

    Pharmacological and physiological phenomena suggest that cells somewhere inside the central nervous system are responsive to aldosterone. Here, we present the fundamental physiological limitations for aldosterone action in the brain, including its limited blood-brain barrier penetration and its substantial competition from glucocorticoids. Recently, a small group of neurons with unusual sensitivity to circulating aldosterone were identified in the nucleus of the solitary tract. We review the discovery and characterization of these neurons, which express the enzyme 11β-hydroxysteroid dehydrogenase type 2, and consider alternative proposals regarding sites and mechanisms for mineralocorticoid action within the brain. PMID:19261742

  19. Psychotherapy and brain plasticity

    PubMed Central

    Collerton, Daniel

    2013-01-01

    In this paper, I will review why psychotherapy is relevant to the question of how consciousness relates to brain plasticity. A great deal of the research and theorizing on consciousness and the brain, including my own on hallucinations for example (Collerton and Perry, 2011) has focused upon specific changes in conscious content which can be related to temporal changes in restricted brain systems. I will argue that psychotherapy, in contrast, allows only a focus on holistic aspects of consciousness; an emphasis which may usefully complement what can be learnt from more specific methodologies. PMID:24046752

  20. 76 FR 58167 - Safety Standard for Play Yards

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-20

    ... Federal Register of December 28, 2010 (75 FR 81766), we issued a final rule on safety standards for non... (75 FR 81766), we issued a final rule on safety standards for non-full-size cribs. Thus, the proposed...-old infant who suffered brain damage. One other injury is associated with play yards, but there...

  1. Brain Gym. Simple Activities for Whole Brain Learning.

    ERIC Educational Resources Information Center

    Dennison, Paul E.; Dennison, Gail E.

    This booklet contains simple movements and activities that are used with students in Educational Kinesiology to enhance their experience of whole brain learning. Whole brain learning through movement repatterning and Brain Gym activities enable students to access those parts of the brain previously unavailable to them. These movements of body and…

  2. A Right Brain/Left Brain Model of Acting.

    ERIC Educational Resources Information Center

    Bowlen, Clark

    Using current right brain/left brain research, this paper develops a model that explains acting's underlying quality--the actor is both himself and the character. Part 1 presents (1) the background of the right brain/left brain theory, (2) studies showing that propositional communication is a left hemisphere function while affective communication…

  3. Brain Gym. Simple Activities for Whole Brain Learning.

    ERIC Educational Resources Information Center

    Dennison, Paul E.; Dennison, Gail E.

    This booklet contains simple movements and activities that are used with students in Educational Kinesiology to enhance their experience of whole brain learning. Whole brain learning through movement repatterning and Brain Gym activities enable students to access those parts of the brain previously unavailable to them. These movements of body and…

  4. Brain Imaging and Behavioral Outcome in Traumatic Brain Injury.

    ERIC Educational Resources Information Center

    Bigler, Erin D.

    1996-01-01

    This review explores the cellular pathology associated with traumatic brain injury (TBI) and its relation to neurobehavioral outcomes, the relationship of brain imaging findings to underlying pathology, brain imaging techniques, various image analysis procedures and how they relate to neuropsychological testing, and the importance of brain imaging…

  5. Management of penetrating brain injury

    PubMed Central

    Kazim, Syed Faraz; Shamim, Muhammad Shahzad; Tahir, Muhammad Zubair; Enam, Syed Ather; Waheed, Shahan

    2011-01-01

    Penetrating brain injury (PBI), though less prevalent than closed head trauma, carries a worse prognosis. The publication of Guidelines for the Management of Penetrating Brain Injury in 2001, attempted to standardize the management of PBI. This paper provides a precise and updated account of the medical and surgical management of these unique injuries which still present a significant challenge to practicing neurosurgeons worldwide. The management algorithms presented in this document are based on Guidelines for the Management of Penetrating Brain Injury and the recommendations are from literature published after 2001. Optimum management of PBI requires adequate comprehension of mechanism and pathophysiology of injury. Based on current evidence, we recommend computed tomography scanning as the neuroradiologic modality of choice for PBI patients. Cerebral angiography is recommended in patients with PBI, where there is a high suspicion of vascular injury. It is still debatable whether craniectomy or craniotomy is the best approach in PBI patients. The recent trend is toward a less aggressive debridement of deep-seated bone and missile fragments and a more aggressive antibiotic prophylaxis in an effort to improve outcomes. Cerebrospinal fluid (CSF) leaks are common in PBI patients and surgical correction is recommended for those which do not close spontaneously or are refractory to CSF diversion through a ventricular or lumbar drain. The risk of post-traumatic epilepsy after PBI is high, and therefore, the use of prophylactic anticonvulsants is recommended. Advanced age, suicide attempts, associated coagulopathy, Glasgow coma scale score of 3 with bilaterally fixed and dilated pupils, and high initial intracranial pressure have been correlated with worse outcomes in PBI patients. PMID:21887033

  6. Artificial selection on relative brain size reveals a positive genetic correlation between brain size and proactive personality in the guppy.

    PubMed

    Kotrschal, Alexander; Lievens, Eva J P; Dahlbom, Josefin; Bundsen, Andreas; Semenova, Svetlana; Sundvik, Maria; Maklakov, Alexei A; Winberg, Svante; Panula, Pertti; Kolm, Niclas

    2014-04-01

    Animal personalities range from individuals that are shy, cautious, and easily stressed (a "reactive" personality type) to individuals that are bold, innovative, and quick to learn novel tasks, but also prone to routine formation (a "proactive" personality type). Although personality differences should have important consequences for fitness, their underlying mechanisms remain poorly understood. Here, we investigated how genetic variation in brain size affects personality. We put selection lines of large- and small-brained guppies (Poecilia reticulata), with known differences in cognitive ability, through three standard personality assays. First, we found that large-brained animals were faster to habituate to, and more exploratory in, open field tests. Large-brained females were also bolder. Second, large-brained animals excreted less cortisol in a stressful situation (confinement). Third, large-brained animals were slower to feed from a novel food source, which we interpret as being caused by reduced behavioral flexibility rather than lack of innovation in the large-brained lines. Overall, the results point toward a more proactive personality type in large-brained animals. Thus, this study provides the first experimental evidence linking brain size and personality, an interaction that may affect important fitness-related aspects of ecology such as dispersal and niche exploration. PMID:24359469

  7. ARTIFICIAL SELECTION ON RELATIVE BRAIN SIZE REVEALS A POSITIVE GENETIC CORRELATION BETWEEN BRAIN SIZE AND PROACTIVE PERSONALITY IN THE GUPPY

    PubMed Central

    Kotrschal, Alexander; Lievens, Eva JP; Dahlbom, Josefin; Bundsen, Andreas; Semenova, Svetlana; Sundvik, Maria; Maklakov, Alexei A; Winberg, Svante; Panula, Pertti; Kolm, Niclas; Morrow, E

    2014-01-01

    Animal personalities range from individuals that are shy, cautious, and easily stressed (a “reactive” personality type) to individuals that are bold, innovative, and quick to learn novel tasks, but also prone to routine formation (a “proactive” personality type). Although personality differences should have important consequences for fitness, their underlying mechanisms remain poorly understood. Here, we investigated how genetic variation in brain size affects personality. We put selection lines of large- and small-brained guppies (Poecilia reticulata), with known differences in cognitive ability, through three standard personality assays. First, we found that large-brained animals were faster to habituate to, and more exploratory in, open field tests. Large-brained females were also bolder. Second, large-brained animals excreted less cortisol in a stressful situation (confinement). Third, large-brained animals were slower to feed from a novel food source, which we interpret as being caused by reduced behavioral flexibility rather than lack of innovation in the large-brained lines. Overall, the results point toward a more proactive personality type in large-brained animals. Thus, this study provides the first experimental evidence linking brain size and personality, an interaction that may affect important fitness-related aspects of ecology such as dispersal and niche exploration. PMID:24359469

  8. Using 3-D shape models to guide segmentation of MR brain images.

    PubMed Central

    Hinshaw, K. P.; Brinkley, J. F.

    1997-01-01

    Accurate segmentation of medical images poses one of the major challenges in computer vision. Approaches that rely solely on intensity information frequently fail because similar intensity values appear in multiple structures. This paper presents a method for using shape knowledge to guide the segmentation process, applying it to the task of finding the surface of the brain. A 3-D model that includes local shape constraints is fitted to an MR volume dataset. The resulting low-resolution surface is used to mask out regions far from the cortical surface, enabling an isosurface extraction algorithm to isolate a more detailed surface boundary. The surfaces generated by this technique are comparable to those achieved by other methods, without requiring user adjustment of a large number of ad hoc parameters. Images Figure 1 Figure 2 Figure 3 Figure 4 PMID:9357670

  9. Embolization of Brain Aneurysms and Fistulas

    MedlinePLUS

    ... Resources Professions Site Index A-Z Embolization of Brain Aneurysms and Arteriovenous Malformations/Fistulas Embolization of brain ... Brain Aneurysms and Fistulas? What is Embolization of Brain Aneurysms and Fistulas? Embolization of brain aneurysms and ...

  10. Src Family Kinases in Brain Edema After Acute Brain Injury.

    PubMed

    Liu, DaZhi; Zhang, Xiong; Hu, BeiLei; Ander, Bradley P

    2016-01-01

    Brain edema, the first stage of intracranial hypertension, has been associated with poor prognosis and increased mortality after acute brain injury such as ischemic stroke, intracranial hemorrhage (ICH), and traumatic brain injury (TBI). Acute brain injury often initiates release of many molecules, including glutamate, adenosine, thrombin, oxyhemoglobin, cytokines, reactive oxygen species (ROS), damage-associated molecular pattern molecules (DAMPs), and others. Most of these molecules activate Src family kinases (SFKs), a family of proto-oncogenic non-receptor tyrosine kinases, resulting in blood-brain barrier (BBB) disruption and brain edema at the acute stage after brain injury. However, SFKs also contribute to BBB self-repair and brain edema resolution in the chronic stage that follows brain injury. In this review, we summarize possible pathways through which SFKs are implicated in both brain edema formation and its eventual resolution. PMID:26463946

  11. Human intelligence and brain networks

    PubMed Central

    Colom, Roberto; Karama, Sherif; Jung, Rex E.; Haier, Richard J.

    2010-01-01

    Intelligence can be defined as a general mental ability for reasoning, problem solving, and learning. Because of its general nature, intelligence integrates cognitive functions such as perception, attention, memory, language, or planning. On the basis of this definition, intelligence can be reliably measured by standardized tests with obtained scores predicting several broad social outcomes such as educational achievement, job performance, health, and longevity. A detailed understanding of the brain mechanisms underlying this general mental ability could provide significant individual and societal benefits. Structural and functional neuroimaging studies have generally supported a frontoparietal network relevant for intelligence. This same network has also been found to underlie cognitive functions related to perception, short-term memory storage, and language. The distributed nature of this network and its involvement in a wide range of cognitive functions fits well with the integrative nature of intelligence. A new key phase of research is beginning to investigate how functional networks relate to structural networks, with emphasis on how distributed brain areas communicate with each other. PMID:21319494

  12. Brain Basics: Understanding Sleep

    MedlinePLUS

    ... People About NINDS Request free mailed brochure Brain Basics: Understanding Sleep Request free mailed brochure Do you ... awakened from stage 1 sleep often remember fragmented visual images. Many also experience sudden muscle contractions called ...

  13. Brain Malignancies Steering Committee

    Cancer.gov

    The Brain Malignancy Steering Committee evaluates and prioritizes concepts for phase 3 and large phase 2 therapeutic clinical trials to be conducted in the NCI National Clinical Trials Network (NCTN).

  14. Bathing the brain

    PubMed Central

    Strittmatter, Warren J.

    2013-01-01

    The brain and spinal cord are surrounded by cerebrospinal fluid, which provides a mechanically stable environment for these delicate structures against the forces of gravity and sudden acceleration and deceleration. Neurons and glia comprising the parenchyma of the brain are enveloped in their microenvironment by interstitial fluid. Interstitial fluid has long been considered to be unaffected by the production and flow of cerebrospinal fluid outside the brain parenchyma. However, two recent papers by Iliff et al. demonstrate that cerebrospinal fluid enters the deep substance of the brain, mixes with the interstitial fluid surrounding neurons and glia, and plays an important role in the exchange and clearance of molecules in the interstitial space of the central nervous system. PMID:23434595

  15. Brain injury - discharge

    MedlinePLUS

    American Association of Neuroscience Nurses, Association of Rehabilitation Nurses. Care of the patient with mild traumatic brain injury. Available at: www.aann.org/pubs/content/guidelines.html. Accessed November 5, 2014. ...

  16. Modular Brain Networks.

    PubMed

    Sporns, Olaf; Betzel, Richard F

    2016-01-01

    The development of new technologies for mapping structural and functional brain connectivity has led to the creation of comprehensive network maps of neuronal circuits and systems. The architecture of these brain networks can be examined and analyzed with a large variety of graph theory tools. Methods for detecting modules, or network communities, are of particular interest because they uncover major building blocks or subnetworks that are particularly densely connected, often corresponding to specialized functional components. A large number of methods for community detection have become available and are now widely applied in network neuroscience. This article first surveys a number of these methods, with an emphasis on their advantages and shortcomings; then it summarizes major findings on the existence of modules in both structural and functional brain networks and briefly considers their potential functional roles in brain evolution, wiring minimization, and the emergence of functional specialization and complex dynamics. PMID:26393868

  17. Brain–kidney crosstalk

    PubMed Central

    2014-01-01

    Encephalopathy and altered higher mental functions are common clinical complications of acute kidney injury. Although sepsis is a major triggering factor, acute kidney injury predisposes to confusion by causing generalised inflammation, leading to increased permeability of the blood–brain barrier, exacerbated by hyperosmolarity and metabolic acidosis due to the retention of products of nitrogen metabolism potentially resulting in increased brain water content. Downregulation of cell membrane transporters predisposes to alterations in neurotransmitter secretion and uptake, coupled with drug accumulation increasing the risk of encephalopathy. On the other hand, acute brain injury can induce a variety of changes in renal function ranging from altered function and electrolyte imbalances to inflammatory changes in brain death kidney donors. PMID:25043644

  18. Brain Coral Christmas

    USGS Multimedia Gallery

    Christmas tree worms have made their home on a brain coral. Tropical corals reefs are complex ecosystems, but are rapidly being lost to bleaching and disease, linked to increasing water temperatures....

  19. The Developing Brain.

    ERIC Educational Resources Information Center

    Schatz, Carla J.

    1992-01-01

    Discusses neural activity and stimulation crucial in fetal brain development and the formation of the mind. Focuses on activity-dependent remodeling related to development of the visual system and retinal activity. (MCO)

  20. Traumatic Brain Injury

    MedlinePLUS

    ... occupational therapy, speech/language therapy, physiatry (physical medicine), psychology/psychiatry, and social support. What is the prognosis? ... clinical settings to better understand TBI and the biological mechanisms underlying damage to the brain. This research ...

  1. Baby Brain Map

    MedlinePLUS

    ... ABOUT US Behavior & Development Brain Development Challenging Behavior Early Childhood Mental Health Early Development From Baby to Big ... of 12 podcasts that translates the research of early childhood development into parenting practices that mothers, fathers and ...

  2. Modular Brain Networks

    PubMed Central

    Sporns, Olaf; Betzel, Richard F.

    2016-01-01

    The development of new technologies for mapping structural and functional brain connectivity has led to the creation of comprehensive network maps of neuronal circuits and systems. The architecture of these brain networks can be examined and analyzed with a large variety of graph theory tools. Methods for detecting modules, or network communities, are of particular interest because they uncover major building blocks or subnetworks that are particularly densely connected, often corresponding to specialized functional components. A large number of methods for community detection have become available and are now widely applied in network neuroscience. This article first surveys a number of these methods, with an emphasis on their advantages and shortcomings; then it summarizes major findings on the existence of modules in both structural and functional brain networks and briefly considers their potential functional roles in brain evolution, wiring minimization, and the emergence of functional specialization and complex dynamics. PMID:26393868

  3. Traumatic Brain Injury

    MedlinePLUS

    ... time it doesn't involve a loss of consciousness. A person who has a concussion may feel ... a mild traumatic brain injury include: Loss of consciousness Headache Confusion Feeling dizzy or lightheaded Blurry vision ...

  4. Brain Tumors (For Parents)

    MedlinePLUS

    ... with brain tumors. This is partly because of new technologies in the operating room and partly because an ... have changed significantly over the last several decades. New computer-assisted technologies allow doctors to construct 3D radiation fields that ...

  5. Brain Tumor Surgery

    MedlinePLUS

    ... or chemotherapy. Enable direct access for chemotherapy, radiation implants, or genetic treatment of malignant tumors. Relieve seizures (due to a brain tumor) that are hard to control. Types The ...

  6. Deep brain stimulation

    MedlinePLUS

    ... stage of surgery depends on where in the brain the stimulator will be placed. The surgeon makes a small opening (incision), usually just below the collarbone and implants the neurostimulator. (Sometimes it is placed under the ...

  7. Brain catechol synthesis - Control by brain tyrosine concentration

    NASA Technical Reports Server (NTRS)

    Wurtman, R. J.; Larin, F.; Mostafapour, S.; Fernstrom, J. D.

    1974-01-01

    Brain catechol synthesis was estimated by measuring the rate at which brain dopa levels rose following decarboxylase inhibition. Dopa accumulation was accelerated by tyrosine administration, and decreased by treatments that lowered brain tyrosine concentrations (for example, intraperitoneal tryptophan, leucine, or parachlorophenylalanine). A low dose of phenylalanine elevated brain tyrosine without accelerating dopa synthesis. Our findings raise the possibility that nutritional and endocrine factors might influence brain catecholamine synthesis by controlling the availability of tyrosine.

  8. The Brain Activity Map

    PubMed Central

    Alivisatos, A. Paul; Chun, Miyoung; Church, George M.; Deisseroth, Karl; Donoghue, John P.; Greenspan, Ralph J.; McEuen, Paul L.; Roukes, Michael L.; Sejnowski, Terrence J.; Weiss, Paul S.; Yuste, Rafael

    2013-01-01

    Neuroscientists have made impressive advances in understanding the microscale function of single neurons and the macroscale activity of the human brain. One can probe molecular and biophysical aspects of individual neurons and also view the human brain in action with magnetic resonance imaging (MRI) or magnetoencephalography (MEG). However, the mechanisms of perception, cognition, and action remain mysterious because they emerge from the real-time interactions of large sets of neurons in densely interconnected, widespread neural circuits. PMID:23470729

  9. The Brain Prize 2011

    PubMed Central

    Soltesz, Ivan

    2012-01-01

    The Grete Lundbeck European Brain Research Foundation awarded the inaugural Brain Prize 2011 to Péter Somogyi, Tamás Freund and György Buzsáki ‘for their wide-ranging, technically and conceptually brilliant research on the functional organization of neuronal circuits in the cerebral cortex, especially in the hippocampus, a region that is crucial for certain forms of memory’. The present article highlights key findings and major conceptual contributions by these three scientists that were recognized by the award. PMID:21917323

  10. Is Brain Emulation Dangerous?

    NASA Astrophysics Data System (ADS)

    Eckersley, Peter; Sandberg, Anders

    2013-12-01

    Brain emulation is a hypothetical but extremely transformative technology which has a non-zero chance of appearing during the next century. This paper investigates whether such a technology would also have any predictable characteristics that give it a chance of being catastrophically dangerous, and whether there are any policy levers which might be used to make it safer. We conclude that the riskiness of brain emulation probably depends on the order of the preceding research trajectory. Broadly speaking, it appears safer for brain emulation to happen sooner, because slower CPUs would make the technology`s impact more gradual. It may also be safer if brains are scanned before they are fully understood from a neuroscience perspective, thereby increasing the initial population of emulations, although this prediction is weaker and more scenario-dependent. The risks posed by brain emulation also seem strongly connected to questions about the balance of power between attackers and defenders in computer security contests. If economic property rights in CPU cycles1 are essentially enforceable, emulation appears to be comparatively safe; if CPU cycles are ultimately easy to steal, the appearance of brain emulation is more likely to be a destabilizing development for human geopolitics. Furthermore, if the computers used to run emulations can be kept secure, then it appears that making brain emulation technologies ―open‖ would make them safer. If, however, computer insecurity is deep and unavoidable, openness may actually be more dangerous. We point to some arguments that suggest the former may be true, tentatively implying that it would be good policy to work towards brain emulation using open scientific methodology and free/open source software codebases

  11. Evolution of brain elaboration.

    PubMed

    Farris, Sarah M

    2015-12-19

    Large, complex brains have evolved independently in several lineages of protostomes and deuterostomes. Sensory centres in the brain increase in size and complexity in proportion to the importance of a particular sensory modality, yet often share circuit architecture because of constraints in processing sensory inputs. The selective pressures driving enlargement of higher, integrative brain centres has been more difficult to determine, and may differ across taxa. The capacity for flexible, innovative behaviours, including learning and memory and other cognitive abilities, is commonly observed in animals with large higher brain centres. Other factors, such as social grouping and interaction, appear to be important in a more limited range of taxa, while the importance of spatial learning may be a common feature in insects with large higher brain centres. Despite differences in the exact behaviours under selection, evolutionary increases in brain size tend to derive from common modifications in development and generate common architectural features, even when comparing widely divergent groups such as vertebrates and insects. These similarities may in part be influenced by the deep homology of the brains of all Bilateria, in which shared patterns of developmental gene expression give rise to positionally, and perhaps functionally, homologous domains. Other shared modifications of development appear to be the result of homoplasy, such as the repeated, independent expansion of neuroblast numbers through changes in genes regulating cell division. The common features of large brains in so many groups of animals suggest that given their common ancestry, a limited set of mechanisms exist for increasing structural and functional diversity, resulting in many instances of homoplasy in bilaterian nervous systems. PMID:26554044

  12. Brain Research: Implications for Education.

    ERIC Educational Resources Information Center

    Crouch-Shinn, Jenella; Shaughnessy, Michael F.

    This paper attempts to examine the research of split-brain, hemispheric specialization, and brain function, as it pertains to handwriting, brain wave patterns, and lateral differences. Studies are reviewed which point to asymmetric differentiated functions and capacities of the two cerebral hemispheres in split-brain patients and in normal…

  13. Brain Research: Implications for Education.

    ERIC Educational Resources Information Center

    Crouch-Shinn, Jenella; Shaughnessy, Michael F.

    This paper attempts to examine the research of split-brain, hemispheric specialization, and brain function, as it pertains to handwriting, brain wave patterns, and lateral differences. Studies are reviewed which point to asymmetric differentiated functions and capacities of the two cerebral hemispheres in split-brain patients and in normal…

  14. Test-retest reliability of white matter structural brain networks: a multiband diffusion MRI study

    PubMed Central

    Zhao, Tengda; Duan, Fei; Liao, Xuhong; Dai, Zhengjia; Cao, Miao; He, Yong; Shu, Ni

    2015-01-01

    The multiband EPI sequence has been developed for the human connectome project to accelerate MRI data acquisition. However, no study has yet investigated the test-retest (TRT) reliability of the graph metrics of white matter (WM) structural brain networks constructed from this new sequence. Here, we employed a multiband diffusion MRI (dMRI) dataset with repeated scanning sessions and constructed both low- and high-resolution WM networks by volume- and surface-based parcellation methods. The reproducibility of network metrics and its dependence on type of construction procedures was assessed by the intra-class correlation coefficient (ICC). We observed conserved topological architecture of WM structural networks constructed from the multiband dMRI data as previous findings from conventional dMRI. For the global network properties, the first order metrics were more reliable than second order metrics. Between two parcellation methods, networks with volume-based parcellation showed better reliability than surface-based parcellation, especially for the global metrics. Between different resolutions, the high-resolution network exhibited higher TRT performance than the low-resolution in terms of the global metrics with a large effect size, whereas the low-resolution performs better in terms of local (region and connection) properties with a relatively low effect size. Moreover, we identified that the association and primary cortices showed higher reproducibility than the paralimbic/limbic regions. The important hub regions and rich-club connections are more reliable than the non-hub regions and connections. Finally, we found WM networks from the multiband dMRI showed higher reproducibility compared with those from the conventional dMRI. Together, our results demonstrated the fair to good reliability of the WM structural brain networks from the multiband EPI sequence, suggesting its potential utility for exploring individual differences and for clinical applications. PMID:25741265

  15. Test-retest reliability of white matter structural brain networks: a multiband diffusion MRI study.

    PubMed

    Zhao, Tengda; Duan, Fei; Liao, Xuhong; Dai, Zhengjia; Cao, Miao; He, Yong; Shu, Ni

    2015-01-01

    The multiband EPI sequence has been developed for the human connectome project to accelerate MRI data acquisition. However, no study has yet investigated the test-retest (TRT) reliability of the graph metrics of white matter (WM) structural brain networks constructed from this new sequence. Here, we employed a multiband diffusion MRI (dMRI) dataset with repeated scanning sessions and constructed both low- and high-resolution WM networks by volume- and surface-based parcellation methods. The reproducibility of network metrics and its dependence on type of construction procedures was assessed by the intra-class correlation coefficient (ICC). We observed conserved topological architecture of WM structural networks constructed from the multiband dMRI data as previous findings from conventional dMRI. For the global network properties, the first order metrics were more reliable than second order metrics. Between two parcellation methods, networks with volume-based parcellation showed better reliability than surface-based parcellation, especially for the global metrics. Between different resolutions, the high-resolution network exhibited higher TRT performance than the low-resolution in terms of the global metrics with a large effect size, whereas the low-resolution performs better in terms of local (region and connection) properties with a relatively low effect size. Moreover, we identified that the association and primary cortices showed higher reproducibility than the paralimbic/limbic regions. The important hub regions and rich-club connections are more reliable than the non-hub regions and connections. Finally, we found WM networks from the multiband dMRI showed higher reproducibility compared with those from the conventional dMRI. Together, our results demonstrated the fair to good reliability of the WM structural brain networks from the multiband EPI sequence, suggesting its potential utility for exploring individual differences and for clinical applications. PMID:25741265

  16. Examining the decomposed brain.

    PubMed

    MacKenzie, James Mackintosh

    2014-12-01

    Examination of the decomposed brain is a largely neglected area of forensic neuropathology. However, careful examination often yields valuable information that may assist in criminal proceedings. Decomposition encompasses the processes of autolysis, putrefaction, and decay. Most decomposed brains will be affected by both autolysis and putrefaction, resulting in a brain that may, at one end of the spectrum, be almost normal or, at the other end, pulpified, depending on the conditions in which the body remained after death and the postmortem interval. Naked eye examination may detect areas of hemorrhage and also guides appropriate sampling for histology. Histological appearances are often better than what would be predicted from the state of the brain. Histology often confirms macroscopic abnormalities and may also reveal other features such as ischemic injury. Silver staining demonstrates neuritic plaques, and immunocytochemistry for ?-amyloid precursor protein and other molecules produces results comparable with those seen in well-preserved fixed brains. The usefulness of information derived from the examination of the decomposed brain in criminal proceedings is illustrated with 6 case reports drawn from the author's own practice. PMID:25384305

  17. The brain metastatic niche.

    PubMed

    Winkler, Frank

    2015-11-01

    Metastasizing cancer cells that arrest in brain microvessels have to face an organ microenvironment that is alien, and exclusive. In order to survive and thrive in this foreign soil, the malignant cells need to successfully master a sequence of steps that includes close interactions with pre-existing brain microvessels, and other nonmalignant cell types. Unfortunately, a relevant number of circulating cancer cells is capable of doing so: brain metastasis is a frequent and devastating complication of solid tumors, becoming ever more important in times where the systemic tumor disease is better controlled and life of cancer patients is prolonged. Thus, it is very important to understand which environmental cues are necessary for effective brain colonization. This review gives an overview of the niches we know, including those who govern cancer cell dormancy, survival, and proliferation in the brain. Colonization of pre-existing niches related to stemness and resistance is a hallmark of successful brain metastasis. A deeper understanding of those host factors can help to identify the most vulnerable steps of the metastatic cascade, which might be most amenable to therapeutic interventions. PMID:26489608

  18. 3D micro-CT imaging of the Postmortem Brain

    PubMed Central

    de Crespigny, Alex; Bou-Reslan, Hani; Nishimura, Merry C.; Phillips, Heidi; Carano, Richard A. D.; D’Arceuil, Helen E.

    2009-01-01

    Magnetic resonance microscopy (?MRI) is becoming an important tool for non-destructive analysis of fixed brain tissue. However, unlike MRI, X-ray computed tomography (CT) scans show little native soft tissue contrast. In this paper, we explored the use of contrast enhanced (brains immersion staining in iodinated CT contrast media) micro-CT (?CT) for high resolution 3D imaging of fixed normal and pathological brains, compared to ?MRI and standard histopathology. An optimum iodine concentration of 0.27M resulted in excellent contrast between gray and white matter in normal brain and a wide range of anatomical structures were identified. In glioma bearing mouse brains, there was clear deliniation of tumor margin which closely matched that seen on histopathology sections. ?CT tumor volume was strongly correlated with histopathology volume. Our data suggests that ?CT image contrast in the immersion-stained brains is related to axonal density and myelin content. Compared to traditional histopathology, our ?CT approach is relatively rapid and less labor intensive. In addition, compared to ?MRI, ?CT is robust and requires much lower equipment and maintenance costs. For simple measurements, such as tumor volume and non-destructive post-mortem brain screening, ?CT may prove to be a valuable alternative to standard histopathology or ?MRI. PMID:18462802

  19. Neuroinformatics of the Allen Mouse Brain Connectivity Atlas.

    PubMed

    Kuan, Leonard; Li, Yang; Lau, Chris; Feng, David; Bernard, Amy; Sunkin, Susan M; Zeng, Hongkui; Dang, Chinh; Hawrylycz, Michael; Ng, Lydia

    2015-02-01

    The Allen Mouse Brain Connectivity Atlas is a mesoscale whole brain axonal projection atlas of the C57Bl/6J mouse brain. Anatomical trajectories throughout the brain were mapped into a common 3D space using a standardized platform to generate a comprehensive and quantitative database of inter-areal and cell-type-specific projections. This connectivity atlas has several desirable features, including brain-wide coverage, validated and versatile experimental techniques, a single standardized data format, a quantifiable and integrated neuroinformatics resource, and an open-access public online database (http://connectivity.brain-map.org/). Meaningful informatics data quantification and comparison is key to effective use and interpretation of connectome data. This relies on successful definition of a high fidelity atlas template and framework, mapping precision of raw data sets into the 3D reference framework, accurate signal detection and quantitative connection strength algorithms, and effective presentation in an integrated online application. Here we describe key informatics pipeline steps in the creation of the Allen Mouse Brain Connectivity Atlas and include basic application use cases. PMID:25536338

  20. Advances in neuroimaging of traumatic brain injury and posttraumatic stress disorder

    PubMed Central

    Van Boven, Robert W.; Harrington, Greg S.; Hackney, David B.; Ebel, Andreas; Gauger, Grant; Bremner, J. Douglas; D’Esposito, Mark; Detre, John A.; Haacke, E. Mark; Jack, Clifford R.; Jagust, William J.; Le Bihan, Denis; Mathis, Chester A.; Mueller, Susanne; Mukherjee, Pratik; Schuff, Norbert; Chen, Anthony; Weiner, Michael W.

    2011-01-01

    Improved diagnosis and treatment of traumatic brain injury (TBI) and posttraumatic stress disorder (PTSD) are needed for our military and veterans, their families, and society at large. Advances in brain imaging offer important biomarkers of structural, functional, and metabolic information concerning the brain. This article reviews the application of various imaging techniques to the clinical problems of TBI and PTSD. For TBI, we focus on findings and advances in neuroimaging that hold promise for better detection, characterization, and monitoring of objective brain changes in symptomatic patients with combat-related, closed-head brain injuries not readily apparent by standard computed tomography or conventional magnetic resonance imaging techniques. PMID:20104401

  1. Standards, Not Standardization: Evoking Quality Student Work.

    ERIC Educational Resources Information Center

    Wiggins, Grant

    1991-01-01

    The only way to improve schools is to ensure that faculties judge local work using authentic standards and measures. Concrete benchmarks are needed that obviate both eccentric teacher grading and simplistic standardized testing. A school has standards when it adopts high, consistent expectations of all learners in all courses. Includes 11…

  2. Standards for Standardized Logistic Regression Coefficients

    ERIC Educational Resources Information Center

    Menard, Scott

    2011-01-01

    Standardized coefficients in logistic regression analysis have the same utility as standardized coefficients in linear regression analysis. Although there has been no consensus on the best way to construct standardized logistic regression coefficients, there is now sufficient evidence to suggest a single best approach to the construction of a…

  3. Mathematics Content Standards Benchmarks and Performance Standards

    ERIC Educational Resources Information Center

    New Mexico Public Education Department, 2008

    2008-01-01

    New Mexico Mathematics Content Standards, Benchmarks, and Performance Standards identify what students should know and be able to do across all grade levels, forming a spiraling framework in the sense that many skills, once introduced, develop over time. While the Performance Standards are set forth at grade-specific levels, they do not exist as…

  4. Partial volume correction of brain perfusion estimates using the inherent signal data of time-resolved arterial spin labeling.

    PubMed

    Ahlgren, André; Wirestam, Ronnie; Petersen, Esben Thade; Ståhlberg, Freddy; Knutsson, Linda

    2014-09-01

    Quantitative perfusion MRI based on arterial spin labeling (ASL) is hampered by partial volume effects (PVEs), arising due to voxel signal cross-contamination between different compartments. To address this issue, several partial volume correction (PVC) methods have been presented. Most previous methods rely on segmentation of a high-resolution T1 -weighted morphological image volume that is coregistered to the low-resolution ASL data, making the result sensitive to errors in the segmentation and coregistration. In this work, we present a methodology for partial volume estimation and correction, using only low-resolution ASL data acquired with the QUASAR sequence. The methodology consists of a T1 -based segmentation method, with no spatial priors, and a modified PVC method based on linear regression. The presented approach thus avoids prior assumptions about the spatial distribution of brain compartments, while also avoiding coregistration between different image volumes. Simulations based on a digital phantom as well as in vivo measurements in 10 volunteers were used to assess the performance of the proposed segmentation approach. The simulation results indicated that QUASAR data can be used for robust partial volume estimation, and this was confirmed by the in vivo experiments. The proposed PVC method yielded probable perfusion maps, comparable to a reference method based on segmentation of a high-resolution morphological scan. Corrected gray matter (GM) perfusion was 47% higher than uncorrected values, suggesting a significant amount of PVEs in the data. Whereas the reference method failed to completely eliminate the dependence of perfusion estimates on the volume fraction, the novel approach produced GM perfusion values independent of GM volume fraction. The intra-subject coefficient of variation of corrected perfusion values was lowest for the proposed PVC method. As shown in this work, low-resolution partial volume estimation in connection with ASL perfusion estimation is feasible, and provides a promising tool for decoupling perfusion and tissue volume. PMID:25066601

  5. Brain Plasticity and Behaviour in the Developing Brain

    PubMed Central

    Kolb, Bryan; Gibb, Robbin

    2011-01-01

    Objective: To review general principles of brain development, identify basic principles of brain plasticity, and discuss factors that influence brain development and plasticity. Method: A literature review of relevant English-language manuscripts on brain development and plasticity was conducted. Results: Brain development progresses through a series of stages beginning with neurogenesis and progressing to neural migration, maturation, synaptogenesis, pruning, and myelin formation. Eight basic principles of brain plasticity are identified. Evidence that brain development and function is influenced by different environmental events such as sensory stimuli, psychoactive drugs, gonadal hormones, parental-child relationships, peer relationships, early stress, intestinal flora, and diet. Conclusions: The development of the brain reflects more than the simple unfolding of a genetic blueprint but rather reflects a complex dance of genetic and experiential factors that shape the emerging brain. Understanding the dance provides insight into both normal and abnormal development. PMID:22114608

  6. Brain/MINDS: brain-mapping project in Japan

    PubMed Central

    Okano, Hideyuki; Miyawaki, Atsushi; Kasai, Kiyoto

    2015-01-01

    There is an emerging interest in brain-mapping projects in countries across the world, including the USA, Europe, Australia and China. In 2014, Japan started a brain-mapping project called Brain Mapping by Integrated Neurotechnologies for Disease Studies (Brain/MINDS). Brain/MINDS aims to map the structure and function of neuronal circuits to ultimately understand the vast complexity of the human brain, and takes advantage of a unique non-human primate animal model, the common marmoset (Callithrix jacchus). In Brain/MINDS, the RIKEN Brain Science Institute acts as a central institute. The objectives of Brain/MINDS can be categorized into the following three major subject areas: (i) structure and functional mapping of a non-human primate brain (the marmoset brain); (ii) development of innovative neurotechnologies for brain mapping; and (iii) human brain mapping; and clinical research. Brain/MINDS researchers are highly motivated to identify the neuronal circuits responsible for the phenotype of neurological and psychiatric disorders, and to understand the development of these devastating disorders through the integration of these three subject areas. PMID:25823872

  7. Brain/MINDS: brain-mapping project in Japan.

    PubMed

    Okano, Hideyuki; Miyawaki, Atsushi; Kasai, Kiyoto

    2015-05-19

    There is an emerging interest in brain-mapping projects in countries across the world, including the USA, Europe, Australia and China. In 2014, Japan started a brain-mapping project called Brain Mapping by Integrated Neurotechnologies for Disease Studies (Brain/MINDS). Brain/MINDS aims to map the structure and function of neuronal circuits to ultimately understand the vast complexity of the human brain, and takes advantage of a unique non-human primate animal model, the common marmoset (Callithrix jacchus). In Brain/MINDS, the RIKEN Brain Science Institute acts as a central institute. The objectives of Brain/MINDS can be categorized into the following three major subject areas: (i) structure and functional mapping of a non-human primate brain (the marmoset brain); (ii) development of innovative neurotechnologies for brain mapping; and (iii) human brain mapping; and clinical research. Brain/MINDS researchers are highly motivated to identify the neuronal circuits responsible for the phenotype of neurological and psychiatric disorders, and to understand the development of these devastating disorders through the integration of these three subject areas. PMID:25823872

  8. The brain's supply and demand in obesity

    PubMed Central

    Kubera, Britta; Hubold, Christian; Zug, Sophia; Wischnath, Hannah; Wilhelm, Ines; Hallschmid, Manfred; Entringer, Sonja; Langemann, Dirk; Peters, Achim

    2012-01-01

    During psychosocial stress, the brain demands extra energy from the body to satisfy its increased needs. For that purpose it uses a mechanism referred to as “cerebral insulin suppression” (CIS). Specifically, activation of the stress system suppresses insulin secretion from pancreatic beta-cells, and in this way energy—particularly glucose—is allocated to the brain rather than the periphery. It is unknown, however, how the brain of obese humans organizes its supply and demand during psychosocial stress. To answer this question, we examined 20 obese and 20 normal weight men in two sessions (Trier Social Stress Test and non-stress control condition followed by either a rich buffet or a meager salad). Blood samples were continuously taken and subjects rated their vigilance and mood by standard questionnaires. First, we found a low reactive stress system in obesity. While obese subjects showed a marked hormonal response to the psychosocial challenge, the cortisol response to the subsequent meal was absent. Whereas the brains of normal weight subjects demanded for extra energy from the body by using CIS, CIS was not detectable in obese subjects. Our findings suggest that the absence of CIS in obese subjects is due to the absence of their meal-related cortisol peak. Second, normal weight men were high reactive during psychosocial stress in changing their vigilance, thereby increasing their cerebral energy need, whereas obese men were low reactive in this respect. Third, normal weight subjects preferred carbohydrates after stress to supply their brain, while obese men preferred fat and protein instead. We conclude that the brain of obese people organizes its need, supply, and demand in a low reactive manner. PMID:22408618

  9. Standards 101: The ASA Standards program

    NASA Astrophysics Data System (ADS)

    Schomer, Paul

    2001-05-01

    ASA serves as a standards developer under the auspices of the American National Standards Institute (ANSI). The Standards Program is organized through four technical committees (S1, S2, S3, and S12) and one administrative committee (ASACOS). S1 deals with physical acoustics, S2 deals with shock and vibration, S3 deals with physiological and psychological acoustics and S12 deals with noise. ASACOS is the ASA Committee on Standards. The program has three primary tasks: (1) development of national standards (ANSI Standards), (2) national adoption of international standards (ANSI NAIS Standards), (3) providing the USA input to the development of international standards (ISO and IEC Standards). At every level the main work is accomplished in Working Groups (WG) that are staffed by hundreds of volunteers, mainly ASA members from its various technical committees such as Noise, Physical Acoustics, Architectural Acoustics, Physiological and Psychological Acoustics, etc. Overall, the Standards Program involves more ASA members than does any other single function of the society except meetings. It is the biggest outreach function of ASA affecting the health, welfare, and economic well-being of large sectors of society. It is a main way the ASA diffuses the knowledge of acoustics and its practical application, perhaps the main way.

  10. Standards 101; the ASA standards program

    NASA Astrophysics Data System (ADS)

    Schomer, Paul D.

    2002-11-01

    ASA supports the development of standards by serving as the secretariat for standards committees of the American National Standards Institute (ANSI). The program is organized through four ANSI technical committees (S1, S2, S3, and S12) and one administrative committee (ASACOS). S1 deals with physical acoustics, S2 deals with shock and vibration, S3 deals with physiological and psychological acoustics, and S12 deals with noise. ASACOS is the ASA Committee on Standards. The program has three primary tasks: (1) the development of National Standards (ANSI Standards), (2) the national adoption of an international standard (ANSI NAIS Standards), (3) providing the USA input to the development of International Standards (ISO and IEC Standards). At every level the main work is accomplished in Working Groups (WG) that are ''staffed'' by hundreds of volunteers--mainly ASA members from its various technical committees such as Noise, Physical Acoustics, Architectural Acoustics, Psychological and Physiological Acoustics, etc. Overall, the Standards Program involves more ASA members than does any other single function of the Society except meetings and it is the biggest outreach function of ASA affecting the health, welfare, and economic well-being of large segments of the population, the business and industrial community, and government at all levels.

  11. Brain Dynamics in Predicting Driving Fatigue Using a Recurrent Self-Evolving Fuzzy Neural Network.

    PubMed

    Liu, Yu-Ting; Lin, Yang-Yin; Wu, Shang-Lin; Chuang, Chun-Hsiang; Lin, Chin-Teng

    2016-02-01

    This paper proposes a generalized prediction system called a recurrent self-evolving fuzzy neural network (RSEFNN) that employs an on-line gradient descent learning rule to address the electroencephalography (EEG) regression problem in brain dynamics for driving fatigue. The cognitive states of drivers significantly affect driving safety; in particular, fatigue driving, or drowsy driving, endangers both the individual and the public. For this reason, the development of brain-computer interfaces (BCIs) that can identify drowsy driving states is a crucial and urgent topic of study. Many EEG-based BCIs have been developed as artificial auxiliary systems for use in various practical applications because of the benefits of measuring EEG signals. In the literature, the efficacy of EEG-based BCIs in recognition tasks has been limited by low resolutions. The system proposed in this paper represents the first attempt to use the recurrent fuzzy neural network (RFNN) architecture to increase adaptability in realistic EEG applications to overcome this bottleneck. This paper further analyzes brain dynamics in a simulated car driving task in a virtual-reality environment. The proposed RSEFNN model is evaluated using the generalized cross-subject approach, and the results indicate that the RSEFNN is superior to competing models regardless of the use of recurrent or nonrecurrent structures. PMID:26595929

  12. Enhancement of brain tumor MR images based on intuitionistic fuzzy sets

    NASA Astrophysics Data System (ADS)

    Deng, Wankai; Deng, He; Cheng, Lifang

    2015-12-01

    Brain tumor is one of the most fatal cancers, especially high-grade gliomas are among the most deadly. However, brain tumor MR images usually have the disadvantages of low resolution and contrast when compared with the optical images. Consequently, we present a novel adaptive intuitionistic fuzzy enhancement scheme by combining a nonlinear fuzzy filtering operation with fusion operators, for the enhancement of brain tumor MR images in this paper. The presented scheme consists of the following six steps: Firstly, the image is divided into several sub-images. Secondly, for each sub-image, object and background areas are separated by a simple threshold. Thirdly, respective intuitionistic fuzzy generators of object and background areas are constructed based on the modified restricted equivalence function. Fourthly, different suitable operations are performed on respective membership functions of object and background areas. Fifthly, the membership plane is inversely transformed into the image plane. Finally, an enhanced image is obtained through fusion operators. The comparison and evaluation of enhancement performance demonstrate that the presented scheme is helpful to determine the abnormal functional areas, guide the operation, judge the prognosis, and plan the radiotherapy by enhancing the fine detail of MR images.

  13. Bacterial Brain Abscess

    PubMed Central

    Patel, Kevin

    2014-01-01

    Significant advances in the diagnosis and management of bacterial brain abscess over the past several decades have improved the expected outcome of a disease once regarded as invariably fatal. Despite this, intraparenchymal abscess continues to present a serious and potentially life-threatening condition. Brain abscess may result from traumatic brain injury, prior neurosurgical procedure, contiguous spread from a local source, or hematogenous spread of a systemic infection. In a significant proportion of cases, an etiology cannot be identified. Clinical presentation is highly variable and routine laboratory testing lacks sensitivity. As such, a high degree of clinical suspicion is necessary for prompt diagnosis and intervention. Computed tomography and magnetic resonance imaging offer a timely and sensitive method of assessing for abscess. Appearance of abscess on routine imaging lacks specificity and will not spare biopsy in cases where the clinical context does not unequivocally indicate infectious etiology. Current work with advanced imaging modalities may yield more accurate methods of differentiation of mass lesions in the brain. Management of abscess demands a multimodal approach. Surgical intervention and medical therapy are necessary in most cases. Prognosis of brain abscess has improved significantly in the recent decades although close follow-up is required, given the potential for long-term sequelae and a risk of recurrence. PMID:25360205

  14. Brain controlled robots

    PubMed Central

    Kawato, Mitsuo

    2008-01-01

    In January 2008, Duke University and the Japan Science and Technology Agency (JST) publicized their successful control of a brain-machine interface for a humanoid robot by a monkey brain across the Pacific Ocean. The activities of a few hundred neurons were recorded from a monkey’s motor cortex in Miguel Nicolelis’s lab at Duke University, and the kinematic features of monkey locomotion on a treadmill were decoded from neural firing rates in real time. The decoded information was sent to a humanoid robot, CB-i, in ATR Computational Neuroscience Laboratories located in Kyoto, Japan. This robot was developed by the JST International Collaborative Research Project (ICORP) as the “Computational Brain Project.” CB-i’s locomotion-like movement was video-recorded and projected on a screen in front of the monkey. Although the bidirectional communication used a conventional Internet connection, its delay was suppressed below one over several seconds, partly due to a video-streaming technique, and this encouraged the monkey’s voluntary locomotion and influenced its brain activity. This commentary introduces the background and future directions of the brain-controlled robot. PMID:19404467

  15. Brain controlled robots.

    PubMed

    Kawato, Mitsuo

    2008-06-01

    In January 2008, Duke University and the Japan Science and Technology Agency (JST) publicized their successful control of a brain-machine interface for a humanoid robot by a monkey brain across the Pacific Ocean. The activities of a few hundred neurons were recorded from a monkey's motor cortex in Miguel Nicolelis's lab at Duke University, and the kinematic features of monkey locomotion on a treadmill were decoded from neural firing rates in real time. The decoded information was sent to a humanoid robot, CB-i, in ATR Computational Neuroscience Laboratories located in Kyoto, Japan. This robot was developed by the JST International Collaborative Research Project (ICORP) as the "Computational Brain Project." CB-i's locomotion-like movement was video-recorded and projected on a screen in front of the monkey. Although the bidirectional communication used a conventional Internet connection, its delay was suppressed below one over several seconds, partly due to a video-streaming technique, and this encouraged the monkey's voluntary locomotion and influenced its brain activity. This commentary introduces the background and future directions of the brain-controlled robot. PMID:19404467

  16. Mapping brains without coordinates

    PubMed Central

    Kötter, Rolf; Wanke, Egon

    2005-01-01

    Brain mapping has evolved considerably over the last century. While most emphasis has been placed on coordinate-based spatial atlases, coordinate-independent parcellation-based mapping is an important technique for accessing the multitude of structural and functional data that have been reported from invasive experiments, and provides for flexible and efficient representations of information. Here, we provide an introduction to motivations, concepts, techniques and implications of coordinate-independent mapping of microstructurally or functionally defined brain structures. In particular, we explain the problems of constructing mapping paths and finding adequate heuristics for their evaluation. We then introduce the three auxiliary concepts of acronym-based mapping (AM), of a generalized hierarchy (GM ontology), and of a topographically oriented regional map (RM) with adequate granularity for mapping between individual brains with different cortical folding and between humans and non-human primates. Examples from the CoCoMac database of primate brain connectivity demonstrate how these concepts enhance coordinate-independent mapping based on published relational statements. Finally, we discuss the strengths and weaknesses of spatial coordinate-based versus coordinate-independent microstructural brain mapping and show perspectives for a wider application of parcellation-based approaches in the integration of multi-modal structural, functional and clinical data. PMID:15971361

  17. Imaging brain plasticity after trauma

    PubMed Central

    Kou, Zhifeng; Iraji, Armin

    2014-01-01

    The brain is highly plastic after stroke or epilepsy; however, there is a paucity of brain plasticity investigation after traumatic brain injury (TBI). This mini review summarizes the most recent evidence of brain plasticity in human TBI patients from the perspective of advanced magnetic resonance imaging. Similar to other forms of acquired brain injury, TBI patients also demonstrated both structural reorganization as well as functional compensation by the recruitment of other brain regions. However, the large scale brain network alterations after TBI are still unknown, and the field is still short of proper means on how to guide the choice of TBI rehabilitation or treatment plan to promote brain plasticity. The authors also point out the new direction of brain plasticity investigation. PMID:25206874

  18. More Complete Removal of Malignant Brain Tumors by Fluorescence-Guided Surgery

    ClinicalTrials.gov

    2015-10-30

    Benign Neoplasms, Brain; Brain Cancer; Brain Neoplasms, Benign; Brain Neoplasms, Malignant; Brain Tumor, Primary; Brain Tumor, Recurrent; Brain Tumors; Intracranial Neoplasms; Neoplasms, Brain; Neoplasms, Intracranial; Primary Brain Neoplasms; Primary Malignant Brain Neoplasms; Primary Malignant Brain Tumors; Gliomas; Glioblastoma

  19. Therapeutic hypothermia for acute brain injuries.

    PubMed

    Andresen, Max; Gazmuri, Jose Tomás; Marín, Arnaldo; Regueira, Tomas; Rovegno, Maximiliano

    2015-01-01

    Therapeutic hypothermia, recently termed target temperature management (TTM), is the cornerstone of neuroprotective strategy. Dating to the pioneer works of Fay, nearly 75 years of basic and clinical evidence support its therapeutic value. Although hypothermia decreases the metabolic rate to restore the supply and demand of O₂, it has other tissue-specific effects, such as decreasing excitotoxicity, limiting inflammation, preventing ATP depletion, reducing free radical production and also intracellular calcium overload to avoid apoptosis. Currently, mild hypothermia (33°C) has become a standard in post-resuscitative care and perinatal asphyxia. However, evidence indicates that hypothermia could be useful in neurologic injuries, such as stroke, subarachnoid hemorrhage and traumatic brain injury. In this review, we discuss the basic and clinical evidence supporting the use of TTM in critical care for acute brain injury that extends beyond care after cardiac arrest, such as for ischemic and hemorrhagic strokes, subarachnoid hemorrhage, and traumatic brain injury. We review the historical perspectives of TTM, provide an overview of the techniques and protocols and the pathophysiologic consequences of hypothermia. In addition, we include our experience of managing patients with acute brain injuries treated using endovascular hypothermia. PMID:26043908

  20. New Antioxidant Drugs for Neonatal Brain Injury

    PubMed Central

    Tataranno, Maria Luisa; Longini, Mariangela; Buonocore, Giuseppe

    2015-01-01

    The brain injury concept covers a lot of heterogeneity in terms of aetiology involving multiple factors, genetic, hemodynamic, metabolic, nutritional, endocrinological, toxic, and infectious mechanisms, acting in antenatal or postnatal period. Increased vulnerability of the immature brain to oxidative stress is documented because of the limited capacity of antioxidant enzymes and the high free radicals (FRs) generation in rapidly growing tissue. FRs impair transmembrane enzyme Na+/K+-ATPase activity resulting in persistent membrane depolarization and excessive release of FR and excitatory aminoacid glutamate. Besides being neurotoxic, glutamate is also toxic to oligodendroglia, via FR effects. Neuronal cells die of oxidative stress. Excess of free iron and deficient iron/binding metabolising capacity are additional features favouring oxidative stress in newborn. Each step in the oxidative injury cascade has become a potential target for neuroprotective intervention. The administration of antioxidants for suspected or proven brain injury is still not accepted for clinical use due to uncertain beneficial effects when treatments are started after resuscitation of an asphyxiated newborn. The challenge for the future is the early identification of high-risk babies to target a safe and not toxic antioxidant therapy in combination with standard therapies to prevent brain injury and long-term neurodevelopmental impairment. PMID:25685254

  1. Mind, brain and psychotherapy.

    PubMed

    Sheth, Hitesh C

    2009-01-01

    There is long-standing debate about superiority of mind over brain, in other words about superiority of mind over matter. And outcome of this debate is going to decide future of psychiatry. The psychiatrists believing in materialism may say that brain is all and by changing neurotransmitters level with new molecules of drugs would cure all illnesses. On the other hand, antipsychiatry activists and some psychotherapists oppose all types of treatment despite of convincing evidence that drug therapy is effective (although sometimes it is not as effective as it claims to be). However, truth lies somewhere in between. Pharmacotherapy and psychotherapy are like two legs of psychiatry and psychiatry cannot walk into a future on one leg. The studies have shown that judicious use of pharmacotherapy along with psychotherapy gives better outcome than any one of them used alone. We must heal dichotomy between mind and brain before we heal the patients. PMID:21938085

  2. The Metastable Brain

    PubMed Central

    Tognoli, Emmanuelle; Kelso, J. A. Scott

    2014-01-01

    Neural ensembles oscillate across a broad range of frequencies and are transiently coupled or “bound” together when people attend to a stimulus, perceive, think and act. This is a dynamic, self-assembling process, with parts of the brain engaging and disengaging in time. But how is it done? The theory of Coordination Dynamics proposes a mechanism called metastability, a subtle blend of integration and segregation. Tendencies for brain regions to express their individual autonomy and specialized functions (segregation, modularity) coexist with tendencies to couple and coordinate globally for multiple functions (integration). Although metastability has garnered increasing attention, it has yet to be demonstrated and treated within a fully spatiotemporal perspective. Here, we illustrate metastability in continuous neural and behavioral recordings, and we discuss theory and experiments at multiple scales suggesting that metastable dynamics underlie the real-time coordination necessary for the brain's dynamic cognitive, behavioral and social functions. PMID:24411730

  3. Brain serotonergic circuitries.

    PubMed

    Charnay, Yves; Léger, Lucienne

    2010-01-01

    Brain serotonergic circuitries interact with other neurotransmitter systems on a multitude of different molecular levels. In humans, as in other mammalian species, serotonin (5-HT) plays a modulatory role in almost every physiological function. Furthermore, serotonergic dysfunction is thought to be implicated in several psychiatric and neurodegenerative disorders. We describe the neuroanatomy and neurochemistry of brain serotonergic circuitries. The contribution of emergent in vivo imaging methods to the regional localization of binding site receptors and certain aspects of their functional connectivity in correlation to behavior is also discussed. 5-HT cell bodies, mainly localized in the raphe nuclei, send axons to almost every brain region. It is argued that the specificity of the local chemocommunication between 5-HT and other neuronal elements mainly depends on mechanisms regulating the extracellular concentration of 5-HT the diversity of high-affinity membrane receptors, and their specific transduction modalities. PMID:21319493

  4. Brain serotonergic circuitries

    PubMed Central

    Charnay, Yves; Leger, Lucienne

    2010-01-01

    Brain serotonergic circuitries interact with other neurotransmitter systems on a multitude of different molecular levels. In humans, as in other mammalian species, serotonin (5-HT) plays a modulatory role in almost every physiological function. Furthermore, serotonergic dysfunction is thought to be implicated in several psychiatric and neurodegenerative disorders. We describe the neuroanatomy and neurochemistry of brain serotonergic circuitries. The contribution of emergent in vivo imaging methods to the regional localization of binding site receptors and certain aspects of their functional connectivity in correlation to behavior is also discussed. 5-HT cell bodies, mainly localized in the raphe nuclei, send axons to almost every brain region. It is argued that the specificity of the local chemocommunication between 5-HT and other neuronal elements mainly depends on mechanisms regulating the extracellular concentration of 5-HT, the diversity of high-affinity membrane receptors, and their specific transduction modalities. PMID:21319493

  5. Mind, Brain and Psychotherapy

    PubMed Central

    Sheth, Hitesh C.

    2009-01-01

    There is long-standing debate about superiority of mind over brain, in other words about superiority of mind over matter. And outcome of this debate is going to decide future of psychiatry. The psychiatrists believing in materialism may say that brain is all and by changing neurotransmitters level with new molecules of drugs would cure all illnesses. On the other hand, antipsychiatry activists and some psychotherapists oppose all types of treatment despite of convincing evidence that drug therapy is effective (although sometimes it is not as effective as it claims to be). However, truth lies somewhere in between. Pharmacotherapy and psychotherapy are like two legs of psychiatry and psychiatry cannot walk into a future on one leg. The studies have shown that judicious use of pharmacotherapy along with psychotherapy gives better outcome than any one of them used alone. We must heal dichotomy between mind and brain before we heal the patients. PMID:21938085

  6. Brain abscess: Current management

    PubMed Central

    Alvis Miranda, Hernando; Castellar-Leones, Sandra Milena; Elzain, Mohammed Awad; Moscote-Salazar, Luis Rafael

    2013-01-01

    Brain abscess (BA) is defined as a focal infection within the brain parenchyma, which starts as a localized area of cerebritis, which is subsequently converted into a collection of pus within a well-vascularized capsule. BA must be differentiated from parameningeal infections, including epidural abscess and subdural empyema. The BA is a challenge for the neurosurgeon because it is needed good clinical, pharmacological, and surgical skills for providing good clinical outcomes and prognosis to BA patients. Considered an infrequent brain infection, BA could be a devastator entity that easily left the patient into dead. The aim of this work is to review the current concepts regarding epidemiology, pathophysiology, etiology, clinical presentation, diagnosis, and management of BA. PMID:24174804

  7. Brains, genes, and primates.

    PubMed

    Izpisua Belmonte, Juan Carlos; Callaway, Edward M; Caddick, Sarah J; Churchland, Patricia; Feng, Guoping; Homanics, Gregg E; Lee, Kuo-Fen; Leopold, David A; Miller, Cory T; Mitchell, Jude F; Mitalipov, Shoukhrat; Moutri, Alysson R; Movshon, J Anthony; Okano, Hideyuki; Reynolds, John H; Ringach, Dario; Sejnowski, Terrence J; Silva, Afonso C; Strick, Peter L; Wu, Jun; Zhang, Feng

    2015-05-01

    One of the great strengths of the mouse model is the wide array of genetic tools that have been developed. Striking examples include methods for directed modification of the genome, and for regulated expression or inactivation of genes. Within neuroscience, it is now routine to express reporter genes, neuronal activity indicators, and opsins in specific neuronal types in the mouse. However, there are considerable anatomical, physiological, cognitive, and behavioral differences between the mouse and the human that, in some areas of inquiry, limit the degree to which insights derived from the mouse can be applied to understanding human neurobiology. Several recent advances have now brought into reach the goal of applying these tools to understanding the primate brain. Here we describe these advances, consider their potential to advance our understanding of the human brain and brain disorders, discuss bioethical considerations, and describe what will be needed to move forward. PMID:25950631

  8. Traumatic brain injury in modern war

    NASA Astrophysics Data System (ADS)

    Ling, Geoffrey S. F.; Hawley, Jason; Grimes, Jamie; Macedonia, Christian; Hancock, James; Jaffee, Michael; Dombroski, Todd; Ecklund, James M.

    2013-05-01

    Traumatic brain injury (TBI) is common and especially with military service. In Iraq and Afghanistan, explosive blast related TBI has become prominent and is mainly from improvised explosive devices (IED). Civilian standard of care clinical practice guidelines (CPG) were appropriate has been applied to the combat setting. When such CPGs do not exist or are not applicable, new practice standards for the military are created, as for TBI. Thus, CPGs for prehospital care of combat TBI CPG [1] and mild TBI/concussion [2] were introduced as was a DoD system-wide clinical care program, the first large scale system wide effort to address all severities of TBI in a comprehensive organized way. As TBI remains incompletely understood, substantial research is underway. For the DoD, leading this effort are The Defense and Veterans Brain Injury Center, National Intrepid Center of Excellence and the Defense Centers of Excellence for Psychological Health and Traumatic Brain Injury. This program is a beginning, a work in progress ready to leverage advances made scientifically and always with the intent of providing the best care to its military beneficiaries.

  9. Protocol-independent brain MRI segmentation method

    NASA Astrophysics Data System (ADS)

    Nyul, Laszlo G.; Udupa, Jayaram K.

    2002-05-01

    We present a segmentation method that combines the robust, accurate, and efficient techniques of fuzzy connectedness with standardized MRI intensities and fast algorithms. The result is a general segmentation framework that more efficiently utilizes the user input (for recognition) and the power of computer (for delineation). This same method has been applied to segment brain tissues from a variety of MRI protocols. Images were corrected for inhomogeneity and standardized to yield tissue-specific intensity values. All parameters for the fuzzy affinity relations were fixed for a specific input protocol. Scale-based fuzzy affinity was used to better capture fine structures. Brain tissues were segmented as 3D fuzzy-connected objects by using relative fuzzy connectedness. The user can specify seed points in about a minute and tracking the 3D fuzzy-connected objects takes about 20 seconds per object. All other computations were performed before any user interaction took place. Segmentation of brain tissues as 3D fuzzy-connected objects from MRI data is feasible at interactive speeds. Utilizing the robust fuzzy connectedness principles and fast algorithms, it is possible to interactively select fuzzy affinity, seed point, and threshold parameters and perform efficient, precise, and accurate segmentations.

  10. Brain shaving: adaptive detection for brain PET data

    NASA Astrophysics Data System (ADS)

    Grecchi, Elisabetta; Doyle, Orla M.; Bertoldo, Alessandra; Pavese, Nicola; Turkheimer, Federico E.

    2014-05-01

    The intricacy of brain biology is such that the variation of imaging end-points in health and disease exhibits an unpredictable range of spatial distributions from the extremely localized to the very diffuse. This represents a challenge for the two standard approaches to analysis, the mass univariate and the multivariate that exhibit either strong specificity but not as good sensitivity (the former) or poor specificity and comparatively better sensitivity (the latter). In this work, we develop an analytical methodology for positron emission tomography that operates an extraction (‘shaving’) of coherent patterns of signal variation while maintaining control of the type I error. The methodology operates two rotations on the image data, one local using the wavelet transform and one global using the singular value decomposition. The control of specificity is obtained by using the gap statistic that selects, within each eigenvector, a subset of significantly coherent elements. Face-validity of the algorithm is demonstrated using a paradigmatic data-set with two radiotracers, [11C]-raclopride and [11C]-(R)-PK11195, measured on the same Huntington's disease patients, a disorder with a genetic based diagnosis. The algorithm is able to detect the two well-known separate but connected processes of dopamine neuronal loss (localized in the basal ganglia) and neuroinflammation (diffusive around the whole brain). These processes are at the two extremes of the distributional envelope, one being very sparse and the latter being perfectly Gaussian and they are not adequately detected by the univariate and the multivariate approaches.

  11. Acute brain trauma.

    PubMed

    Martin, G T

    2016-01-01

    In the 20th century, the complications of head injuries were controlled but not eliminated. The wars of the 21st century turned attention to blast, the instant of impact and the primary injury of concussion. Computer calculations have established that in the first 5 milliseconds after the impact, four independent injuries on the brain are inflicted: 1) impact and its shockwave, 2) deceleration, 3) rotation and 4) skull deformity with vibration (or resonance). The recovery, pathology and symptoms after acute brain trauma have always been something of a puzzle. The variability of these four modes of injury, along with a variable reserve of neurones, explains some of this problem. PMID:26688392

  12. Brain monitoring in children.

    PubMed

    Sury, Michael

    2014-03-01

    Applying scalp sensors in the operating theater, intensive care, or resuscitation scenarios to detect and monitor brain function is achievable, practical, and affordable. The modalities are complex and the output of the monitor needs careful interpretation. The monitor may have technical problems, and a single reading must be considered with caution. These monitors may have a use for monitoring trends in specific situations, but evidence does not support their widespread use. Nevertheless, research should continue to investigate their role. Future techniques and treatments may show that these monitors can monitor brain function and prevent harm. PMID:24491653

  13. MRI Helps Detect Brain Bleeding Soon After Traumatic Brain Injury

    MedlinePLUS

    ... Español You Are Here: Home ? Latest Health News ? Article URL of this page: https://www.nlm.nih.gov/medlineplus/news/fullstory_154640.html MRI Helps Detect Brain Bleeding Soon After Traumatic Brain Injury Military study ...

  14. Study of a brain hyperthermia system providing also passive brain temperature monitoring.

    PubMed

    Karanasiou, Irene S; Uzunoglu, Nikolaos K

    2006-01-01

    A newly developed system for deep brain hyperthermia able to provide also passive measurements of temperature distributions inside the human body and especially the brain, is presented in this paper. The proposed system able to comprise both therapeutic and diagnostic modules operates in a totally non-invasive contactless way based on the use of an ellipsoidal conductive wall cavity to achieve beamforming and focusing on the areas under treatment and temperature monitoring. The performance of the system's diagnostic module designed and developed for brain imaging, has been previously studied in phantom, animal and human tests illustrating promising results. In the present paper theoretical analysis of the therapeutic module designed for hyperthermia treatment, elicited during simulation performance, exhibit the system's focusing attributes. Moreover, initial phantom experimental results verify the proof of concept. Taking into consideration the present initial theoretical and experimental study and the great advantage of the proposed brain hyperthermia system of being non invasive and with a very acceptable cost, it is concluded that further research is required in order to explore its potentials at becoming a part of the standard treatment protocol of brain malignancy in the future. PMID:17946670

  15. Stereotactic PET atlas of the human brain: Aid for visual interpretation of functional brain images

    SciTech Connect

    Minoshima, S.; Koeppe, R.A.; Frey, A.; Ishihara, M.; Kuhl, D.E.

    1994-06-01

    In the routine analysis of functional brain images obtained by PET, subjective visual interpretation is often used for anatomic localization. To enhance the accuracy and consistency of the anatomic interpretation, a PET stereotactic atlas and localization approach was designed for functional brain images. The PET atlas was constructed from a high-resolution [{sup 18}F]fluorodeoxyglucose (FDG) image set of a normal volunteer (a 41-yr-ld woman). The image set was reoriented stereotactically, according to the intercommissural (anterior and posterior commissures) line and transformed to the standard stereotactic atlas coordinates. Cerebral structures were annotated on the transaxial planes using a proportional grid system and surface-rendered images. The stereotactic localization technique was applied to image sets from patients with Alzheimer`s disease, and areas of functional alteration were localized visually by referring to the PET atlas. Major brain structures were identified on both transaxial planes and surface-rendered images. In the stereotactic system, anatomic correspondence between the PET atlas and stereotactically reoriented individual image sets of patients with Alzheimer`s disease facilitated both indirect and direct localization of the cerebral structures. Because rapid stereotactic alignment methods for PET images are now available for routine use, the PET atlas will serve as an aid for visual interpretation of functional brain images in the stereotactic system. Widespread application of stereotactic localization may be used in functional brain images, not only in the research setting, but also in routine clinical situations. 41 refs., 3 figs.

  16. Left Brain/Right Brain Learning for Adult Education.

    ERIC Educational Resources Information Center

    Garvin, Barbara

    1986-01-01

    Contrasts and compares the theory and practice of adult education as it relates to the issue of right brain/left brain learning. The author stresses the need for a whole-brain approach to teaching and suggests that adult educators, given their philosophical directions, are the perfect potential users of this integrated system. (Editor/CT)

  17. Even Mild Traumatic Brain Injury May Cause Brain Damage

    MedlinePLUS

    ... MINNEAPOLIS – Even mild traumatic brain injury may cause brain damage and thinking and memory problems, according to a study published ... One year after the injury, the scores on thinking and memory tests were the same for people with brain injuries and those with no injuries, but there ...

  18. Teaching Creativity for Right Brain and Left Brain Thinkers.

    ERIC Educational Resources Information Center

    Geske, Joel

    Right brain and left brain dominant people process information differently and need different techniques to learn how to become more creative. Various exercises can help students take advantage of both sides of their brains. Students must feel comfortable and unthreatened to reach maximal creativity, and a positive personal relationship with…

  19. Brain Imaging: Applications in Psychiatry.

    ERIC Educational Resources Information Center

    Andreasen, Nancy C.

    1988-01-01

    Discusses various brain imaging techniques, including computed tomography, magnetic resonance imaging, measurement of regional cerebral blood flow, single photo emission tomography, and position emission tomography. Describes the uses of these techniques in helping to understand brain functioning. (TW)

  20. Drugs Approved for Brain Tumors

    MedlinePLUS

    ... Ask about Your Treatment Research Drugs Approved for Brain Tumors This page lists cancer drugs approved by ... that are not listed here. Drugs Approved for Brain Tumors Afinitor (Everolimus) Afinitor Disperz (Everolimus) Avastin (Bevacizumab) ...

  1. Development of the Young Brain

    MedlinePLUS

    ... items) Treatments (11 items) Development of the Young Brain May 2, 2011 For more than twenty years, ... Giedd has studied the development of the adolescent brain. Decades of imaging work have led to remarkable ...

  2. TRAUMATIC BRAIN INJURY (TBI) DATABASE

    EPA Science Inventory

    The Traumatic Brain Injury National Data Center (TBINDC) at Kessler Medical Rehabilitation Research and Education Center is the coordinating center for the research and dissemination efforts of the Traumatic Brain Injury Model Systems (TBIMS) program funded by the National Instit...

  3. Brain banking for neurological disorders.

    PubMed

    Samarasekera, Neshika; Al-Shahi Salman, Rustam; Huitinga, Inge; Klioueva, Natasja; McLean, Catriona A; Kretzschmar, Hans; Smith, Colin; Ironside, James W

    2013-11-01

    Brain banks are used to gather, store, and provide human brain tissue for research and have been fundamental to improving our knowledge of the brain in health and disease. To maintain this role, the legal and ethical issues relevant to the operations of brain banks need to be more widely understood. In recent years, researchers have reported that shortages of high-quality brain tissue samples from both healthy and diseased people have impaired their efforts. Closer collaborations between brain banks and improved strategies for brain donation programmes will be essential to overcome these problems as the demand for brain tissue increases and new research techniques become more widespread, with the potential for substantial scientific advances in increasingly common neurological disorders. PMID:24074724

  4. Magnetic Resonance Imaging (MRI): Brain

    MedlinePLUS

    ... All About Food Allergies Magnetic Resonance Imaging (MRI): Brain KidsHealth > For Parents > Magnetic Resonance Imaging (MRI): Brain ... child may be given headphones to listen to music or earplugs to block the noise, and will ...

  5. Brain Stimulation in Neurology and Psychiatry

    PubMed Central

    Little, Simon; Brown, Peter

    2012-01-01

    Feedback control of deep brain stimulation (DBS) in Parkinson's disease has great potential to improve efficacy, reduce side effects, and decrease the cost of treatment. In this, the timing and intensity of stimulation are titrated according to biomarkers that capture current clinical state. Stimulation may be at standard high frequency or intelligently patterned to directly modify specific pathological rhythms. The search for and validation of appropriate feedback signals are therefore crucial. Signals recorded from the DBS electrode currently appear to be the most promising source of feedback. In particular, beta-frequency band oscillations in the local field potential recorded at the stimulation target may capture variation in bradykinesia and rigidity across patients, but this remains to be confirmed within patients. Biomarkers that reliably reflect other impairments, such as tremor, also need to be established. Finally, whether brain signals are causally important needs to be established before stimulation can be specifically patterned rather than delivered at empirically defined high frequency. PMID:22830645

  6. Traumatic Brain Injury in Sports: A Review

    PubMed Central

    Sahler, Christopher S.; Greenwald, Brian D.

    2012-01-01

    Traumatic brain injury (TBI) is a clinical diagnosis of neurological dysfunction following head trauma, typically presenting with acute symptoms of some degree of cognitive impairment. There are an estimated 1.7 to 3.8 million TBIs each year in the United States, approximately 10 percent of which are due to sports and recreational activities. Most brain injuries are self-limited with symptom resolution within one week, however, a growing amount of data is now establishing significant sequelae from even minor impacts such as headaches, prolonged cognitive impairments, or even death. Appropriate diagnosis and treatment according to standardized guidelines are crucial when treating athletes who may be subjected to future head trauma, possibly increasing their likelihood of long-term impairments. PMID:22848836

  7. Fast automatic segmentation of the brain in T1-weighted volume MRI data

    NASA Astrophysics Data System (ADS)

    Lemieux, Louis; Hagemann, Georg; Krakow, Karsten; Woermann, Friedrich G.

    1999-05-01

    A fully automated algorithm was developed to segment the brain from T1-weighted volume MR images. Automatic non- uniformity correction is performed prior to segmentation. The segmentation algorithm is based on automatic thresholding and morphological operations. It is fully 3D and therefore independent of scan orientation. The validity and performance of the algorithm were evaluated by comparing the automatically calculated brain volume with semi- automated measurements in 10 subjects. The amount of non- brain tissue included in the automatic segmentation was calculated. To test reproducibility, the brain volume was calculated in repeated scans in another 10 subjects. The mean and standard deviation of the difference between the semi-automated and automated measurements were 0.6% and 2.8% of the mean brain volume, respectively, which is within the inter-observer variability of the semi-automatic method. The mean amount of non-brain tissue contained in the segmented brain mask was 0.3% of the mean brain volume, with a standard deviation of 0.2%. The mean and standard deviation of the difference between the total volumes calculated from repeated scans were 0.4% and 1.2% of the mean brain volume, respectively.

  8. Arizona Academic Standards: Kindergarten

    ERIC Educational Resources Information Center

    Arizona Department of Education, 2009

    2009-01-01

    This publication contains Arizona public schools' academic standards for kindergarten. The contents of this document include the following: (1) The Arts Standard 2006--Kindergarten; (2) Comprehensive Health Education/Physical Activity Standards 1997--Readiness (Kindergarten); (3) Foreign and Native Language Standards 1997--Readiness…

  9. Technology Standards for Students.

    ERIC Educational Resources Information Center

    Burke, Jennifer

    In many states technology standards for students have focused on basic computer skills, but more standards are beginning to focus on identifying technology skills that students need for school and the workplace. In most states in the Southern Region, technology standards for students are based on the National Educational Technology Standards for…

  10. Standards for holdup measurement

    SciTech Connect

    Zucker, M.S.

    1982-01-01

    Holdup measurement, needed for material balance, depend intensively on standards and on interpretation of the calibration procedure. More than other measurements, the calibration procedure using the standard becomes part of the standard. Standards practical for field use and calibration techniques have been developed. While accuracy in holdup measurements is comparatively poor, avoidance of bias is a necessary goal.

  11. English Proficiency Standards.

    ERIC Educational Resources Information Center

    Oregon Univ. System, Eugene. Office of the Chancellor.

    This paper presents the current PASS (Proficiency-based Admission Standards System) Proficiency Standards in English and answers the question of what students should be able to do upon admission to the Oregon University System. The PASS standards in the paper are aligned with and complement the standards, scoring guides, and test specifications…

  12. Minds, Brains and Education

    ERIC Educational Resources Information Center

    Bakhurst, David

    2008-01-01

    It is often argued that neuroscience can be expected to provide insights of significance for education. Advocates of this view are sometimes committed to "brainism", the view (a) that an individual's mental life is constituted by states, events and processes in her brain, and (b) that psychological attributes may legitimately be ascribed to the…

  13. Mapping the Brain.

    ERIC Educational Resources Information Center

    Begley, Sharon; And Others

    1992-01-01

    Describes powerful new devices that "peer" through skull and "see" brain at work allowing neuroscientists to pursue the well springs of thought and emotion in their search for the origins of intelligence and language. Discusses the following scanning technologies: Magnetic Resonance Imaging (MRI), Positron Emission Tomography (PET),…

  14. Infections and Brain Development

    PubMed Central

    Cordeiro, Christina N.; Tsimis, Michael; Burd, Irina

    2016-01-01

    Several different bodies of evidence support a link between infection and altered brain development. Maternal infections, such as influenza and human immunodeficiency virus, have been linked to the development of autism spectrum disorders, differences in cognitive test scores, and bipolar disorder; an association that has been shown in both epidemiologic and retrospective studies. Several viral, bacterial, and parasitic illnesses are associated with alterations in fetal brain structural anomalies including brain calcifications and hydrocephalus. The process of infection can activate inflammatory pathways causing the release of various proinflammatory biomarkers and histological changes consistent with an infectious intrauterine environment (chorioamnionitis) or umbilical cord (funisitis). Elevations in inflammatory cytokines are correlated with cerebral palsy, schizophrenias, and autism. Animal studies indicate that the balance of proinflammatory and anti-inflammatory cytokines is critical to the effect prenatal inflammation plays in neurodevelopment. Finally, chorioamnionitis is associated with cerebral palsy and other abnormal neurodevelopmental outcomes. In conclusion, a plethora of evidence supports, albeit with various degrees of certainty, the theory that maternal infection and inflammation that occur during critical periods of fetal development could theoretically alter brain structure and function in a time-sensitive manner. PMID:26490164

  15. Diagnosis of brain death

    PubMed Central

    Machado, Calixto

    2010-01-01

    Brain death (BD) should be understood as the ultimate clinical expression of a brain catastrophe characterized by a complete and irreversible neurological stoppage, recognized by irreversible coma, absent brainstem reflexes, and apnea. The most common pattern is manifested by an elevation of intracranial pressure to a point beyond the mean arterial pressure, and hence cerebral perfusion pressure falls and, as a result, no net cerebral blood flow is present, in due course leading to permanent cytotoxic injury of the intracranial neuronal tissue. A second mechanism is an intrinsic injury affecting the nervous tissue at a cellular level which, if extensive and unremitting, can also lead to BD. We review here the methodology of diagnosing death, based on finding any of the signs of death. The irreversible loss of cardio-circulatory and respiratory functions can cause death only when ischemia and anoxia are prolonged enough to produce an irreversible destruction of the brain. The sign of such loss of brain functions, that is to say BD diagnosis, is fully reviewed. PMID:21577338

  16. Higher Brain Function.

    ERIC Educational Resources Information Center

    Chiaia, N.L.; Teyler, T.J.

    1983-01-01

    Focuses on how learning works. Discusses three major components related to processing information--sensory and perceptual systems, integration of information, and output of information--and developmental and environmental factors affecting brain information in each of these areas. Concludes with discussion of biological bases for cognitive and…

  17. Acquired Brain Injury Program.

    ERIC Educational Resources Information Center

    Schwartz, Stacey Hunter

    This paper reviews the Acquired Brain Injury (ABI) Program at Coastline Community College (California). The ABI Program is a two-year, for-credit educational curriculum designed to provide structured cognitive retraining for adults who have sustained an ABI due to traumatic (such as motor vehicle accident or fall) or non-traumatic(such as…

  18. Silicon and Software Brains.

    ERIC Educational Resources Information Center

    Barden, William, Jr.

    1991-01-01

    Discussed are the developments in neural networks technology that promise to make computers a great deal smarter. The brain is described, and its workings are compared to that of a computer. Computer programs that allow the construction of a simulated neural network are discussed and evaluated. (KR)

  19. Sleep, Memory & Brain Rhythms

    PubMed Central

    Watson, Brendon O.; Buzsáki, György

    2015-01-01

    Sleep occupies roughly one-third of our lives, yet the scientific community is still not entirely clear on its purpose or function. Existing data point most strongly to its role in memory and homeostasis: that sleep helps maintain basic brain functioning via a homeostatic mechanism that loosens connections between overworked synapses, and that sleep helps consolidate and re-form important memories. In this review, we will summarize these theories, but also focus on substantial new information regarding the relation of electrical brain rhythms to sleep. In particular, while REM sleep may contribute to the homeostatic weakening of overactive synapses, a prominent and transient oscillatory rhythm called “sharp-wave ripple” seems to allow for consolidation of behaviorally relevant memories across many structures of the brain. We propose that a theory of sleep involving the division of labor between two states of sleep–REM and non-REM, the latter of which has an abundance of ripple electrical activity–might allow for a fusion of the two main sleep theories. This theory then postulates that sleep performs a combination of consolidation and homeostasis that promotes optimal knowledge retention as well as optimal waking brain function. PMID:26097242

  20. From Ear to Brain

    ERIC Educational Resources Information Center

    Kimura, Doreen

    2011-01-01

    In this paper Doreen Kimura gives a personal history of the "right-ear effect" in dichotic listening. The focus is on the early ground-breaking papers, describing how she did the first dichotic listening studies relating the effects to brain asymmetry. The paper also gives a description of the visual half-field technique for lateralized stimulus…

  1. To Build a Brain

    ERIC Educational Resources Information Center

    Miller, Julie Ann

    1977-01-01

    Describes use of electronic model to simulate electrical patterns resulting from nerve cell interactions in the brain. Resembles nerve cell activity realistically in that the model produces signals above a set threshold, its firing activity varies, a refractory period is required before second firing, and it displays plasticity. (CS)

  2. [Brain metastases imaging].

    PubMed

    Delmaire, C; Savatovsky, J; Boulanger, T; Dhermain, F; Le Rhun, E; Météllus, P; Gerber, S; Carsin-Nicole, B; Petyt, G

    2015-02-01

    The therapeutic management of brain metastases depends upon their diagnosis and characteristics. It is therefore imperative that imaging provides accurate diagnosis, identification, size and localization information of intracranial lesions in patients with presumed cerebral metastatic disease. MRI exhibits superior sensitivity to CT for small lesions identification and to evaluate their precise anatomical location. The CT-scan will be made only in case of MRI's contraindication or if MRI cannot be obtained in an acceptable delay for the management of the patient. In clinical practice, the radiologic metastasis evaluation is based on visual image analyses. Thus, a particular attention is paid to the imaging protocol with the aim to optimize the diagnosis of small lesions and to evaluate their evolution. The MRI protocol must include: 1) non-contrast T1, 2) diffusion, 3) T2* or susceptibility-weighted imaging, 4) dynamic susceptibility contrast perfusion, 5) FLAIR with contrast injection, 6) T1 with contrast injection preferentially using the 3D spin echo images. The role of the nuclear medicine imaging is still limited in the diagnosis of brain metastasis. The Tc-sestamibi brain imaging or PET with amino acid tracers can differentiate local brain metastasis recurrence from radionecrosis but still to be evaluated. PMID:25649387

  3. Infections and Brain Development.

    PubMed

    Cordeiro, Christina N; Tsimis, Michael; Burd, Irina

    2015-10-01

    Several different bodies of evidence support a link between infection and altered brain development. Maternal infections, such as influenza and human immunodeficiency virus, have been linked to the development of autism spectrum disorders, differences in cognitive test scores, and bipolar disorder; an association that has been shown in both epidemiologic and retrospective studies. Several viral, bacterial, and parasitic illnesses are associated with alterations in fetal brain structural anomalies including brain calcifications and hydrocephalus. The process of infection can activate inflammatory pathways causing the release of various proinflammatory biomarkers and histological changes consistent with an infectious intrauterine environment (chorioamnionitis) or umbilical cord (funisitis). Elevations in inflammatory cytokines are correlated with cerebral palsy, schizophrenias, and autism. Animal studies indicate that the balance of proinflammatory and anti-inflammatory cytokines is critical to the effect prenatal inflammation plays in neurodevelopment. Finally, chorioamnionitis is associated with cerebral palsy and other abnormal neurodevelopmental outcomes. In conclusion, a plethora of evidence supports, albeit with various degrees of certainty, the theory that maternal infection and inflammation that occur during critical periods of fetal development could theoretically alter brain structure and function in a time-sensitive manner. PMID:26490164

  4. Brain Games for Babies.

    ERIC Educational Resources Information Center

    Silberg, Jackie

    2001-01-01

    Presents games for caregivers to use with infants to enhance brain development. Includes games that develop trust and security, language skills, and fine motor skills, as well as games that are fun or stimulate vision. Includes videotape references for parents and caregivers. (KB)

  5. Ben's Plastic Brain

    ERIC Educational Resources Information Center

    Kaplan, Susan L.

    2010-01-01

    This article shares a story of Ben who as a result of his premature birth, suffered a brain hemorrhage resulting in cerebral palsy, which affected his left side (left hemiparesis) and caused learning disabilities. Despite these challenges, he graduated from college and currently works doing information management for a local biotech start-up…

  6. Montessori and Brain Research.

    ERIC Educational Resources Information Center

    Hranitz, John R.

    Researchers in medicine, education, and related fields continue to make new discoveries about how the brain functions or malfunctions. The implications of studies of how young children learn compare favorably with those of educators such as Maria Montessori, Jerome Bruner, and Jean Piaget. These researchers saw growth and development as a series…

  7. Aging Brain, Aging Mind.

    ERIC Educational Resources Information Center

    Selkoe, Dennis J.

    1992-01-01

    Discusses the aging process related to physical changes of the human neural structure involved in learning, memory, and reasoning. Presents evidence that indicates such alterations do not necessarily signal the decline in cognitive function. Vignettes provide images of brain structures involved in learning, memory, and reasoning; hippocampal…

  8. Our Brains Extended

    ERIC Educational Resources Information Center

    Prensky, Marc

    2013-01-01

    Technology is an extension of the brain; it is a new way of thinking. It is the solution humans have created to deal with the difficult new context of variability, uncertainty, complexity, and ambiguity. Wise integration of evolving and powerful technology demands a rethinking of the curriculum. This article discusses technology as the new way of…

  9. Brain Chemistry and Behavior.

    ERIC Educational Resources Information Center

    Spaziano, Vincent T.; Gibbons, Judith L.

    1986-01-01

    Describes an interdisciplinary course providing basic background in behavior, pharmacology, neuroanatomy, neurotransmitters, drugs, and specific brain disorders. Provides rationale, goals, and operational details. Discusses a research project as a tool to improve critical evaluation of science reporting and writing skills. (JM)

  10. Our Brains Extended

    ERIC Educational Resources Information Center

    Prensky, Marc

    2013-01-01

    Technology is an extension of the brain; it is a new way of thinking. It is the solution humans have created to deal with the difficult new context of variability, uncertainty, complexity, and ambiguity. Wise integration of evolving and powerful technology demands a rethinking of the curriculum. This article discusses technology as the new way of…

  11. From Ear to Brain

    ERIC Educational Resources Information Center

    Kimura, Doreen

    2011-01-01

    In this paper Doreen Kimura gives a personal history of the "right-ear effect" in dichotic listening. The focus is on the early ground-breaking papers, describing how she did the first dichotic listening studies relating the effects to brain asymmetry. The paper also gives a description of the visual half-field technique for lateralized stimulus…

  12. Minds, Brains and Education

    ERIC Educational Resources Information Center

    Bakhurst, David

    2008-01-01

    It is often argued that neuroscience can be expected to provide insights of significance for education. Advocates of this view are sometimes committed to "brainism", the view (a) that an individual's mental life is constituted by states, events and processes in her brain, and (b) that psychological attributes may legitimately be ascribed to the…

  13. Brain Peptides and Psychopharmacology

    ERIC Educational Resources Information Center

    Arehart-Treichel, Joan

    1976-01-01

    Proteins isolated from the brain and used as drugs can improve and apparently even transfer mental states and behavior. Much of the pioneering work and recent research with humans and animals is reviewed and crucial questions that are being posed about the psychologically active peptides are related. (BT)

  14. Your Brain Outdoors

    ERIC Educational Resources Information Center

    MacEachren, Zabe

    2012-01-01

    The way technology influences a person's cognition is seldom recognized, but is of increasing interest among brain researchers. Outdoor educators tend to pay attention to the way different activities offer different perceptions of an environment. When natural spaces can no longer be accessed, they adapt and simulate natural activities in available…

  15. Rethinking brain food

    Technology Transfer Automated Retrieval System (TEKTRAN)

    If omega-3 (n-3) fatty acids are the functional food du jour, then that "jour" must first have been the 5th day of creation (according to Genesis 1:21), when the marine fish were created and exhorted to be fruitful and multiply. The exact time when these marine species became "brain food" for peopl...

  16. Brain surgery - discharge

    MedlinePLUS

    ... A small hole was then drilled into your skull bone or a piece of your skull bone was removed. This was done so that the ... operate on your brain. If a piece of skull bone was removed, at the end of surgery it ...

  17. Concentrating on the Brain.

    ERIC Educational Resources Information Center

    Johnson, Virginia Ruth

    1985-01-01

    Discusses the human brain's specialized perception/expression and information processing systems as they relate to student learning. For high school students in the formal reasoning stage, it is suggested that teachers provide instruction based on mental exercises to develop problem-solving insight. (DH)

  18. Coping with brain damage

    NASA Technical Reports Server (NTRS)

    Waring, W.

    1974-01-01

    Two neurological disorders, cerebral palsy, and traumatic brain damage as from an accident, are considered. The discussion covers the incidence of disabilities, their characteristics, and what is now being done to deal with them, particularly in reference to areas in which the capabilities of the engineer can be effectively applied.

  19. Mapping the Brain.

    ERIC Educational Resources Information Center

    Begley, Sharon; And Others

    1992-01-01

    Describes powerful new devices that "peer" through skull and "see" brain at work allowing neuroscientists to pursue the well springs of thought and emotion in their search for the origins of intelligence and language. Discusses the following scanning technologies: Magnetic Resonance Imaging (MRI), Positron Emission Tomography (PET),…

  20. The Brain Revolution.

    ERIC Educational Resources Information Center

    Sylwester, Robert

    1998-01-01

    A cognitive-science revolution, reminiscent of Dewey's Progressive Education Movement, will profoundly affect future educational policy and practice. A comprehensive brain theory will emerge out of Darwin's discoveries about natural selection as a scientific explanation for biodiversity, Einstein's theoretical reconceptualization of…