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Sample records for single lobed farfield

  1. Quantitative and Isolated Measurement of Far-Field Light Scattering by a Single Nanostructure

    Science.gov (United States)

    Kim, Donghyeong; Jeong, Kwang-Yong; Kim, Jinhyung; Ee, Ho-Seok; Kang, Ju-Hyung; Park, Hong-Gyu; Seo, Min-Kyo

    2017-11-01

    Light scattering by nanostructures has facilitated research on various optical phenomena and applications by interfacing the near fields and free-propagating radiation. However, direct quantitative measurement of far-field scattering by a single nanostructure on the wavelength scale or less is highly challenging. Conventional back-focal-plane imaging covers only a limited solid angle determined by the numerical aperture of the objectives and suffers from optical aberration and distortion. Here, we present a quantitative measurement of the differential far-field scattering cross section of a single nanostructure over the full hemisphere. In goniometer-based far-field scanning with a high signal-to-noise ratio of approximately 27.4 dB, weak scattering signals are efficiently isolated and detected under total-internal-reflection illumination. Systematic measurements reveal that the total and differential scattering cross sections of a Au nanorod are determined by the plasmonic Fabry-Perot resonances and the phase-matching conditions to the free-propagating radiation, respectively. We believe that our angle-resolved far-field measurement scheme provides a way to investigate and evaluate the physical properties and performance of nano-optical materials and phenomena.

  2. Pareto optimality between width of central lobe and peak sidelobe intensity in the far-field pattern of lossless phase-only filters for enhancement of transverse resolution.

    Science.gov (United States)

    Mukhopadhyay, Somparna; Hazra, Lakshminarayan

    2015-11-01

    Resolution capability of an optical imaging system can be enhanced by reducing the width of the central lobe of the point spread function. Attempts to achieve the same by pupil plane filtering give rise to a concomitant increase in sidelobe intensity. The mutual exclusivity between these two objectives may be considered as a multiobjective optimization problem that does not have a unique solution; rather, a class of trade-off solutions called Pareto optimal solutions may be generated. Pareto fronts in the synthesis of lossless phase-only pupil plane filters to achieve superresolution with prespecified lower limits for the Strehl ratio are explored by using the particle swarm optimization technique.

  3. Biochemical characterization of the bi-lobe reveals a continuous structural network linking the bi-lobe to other single-copied organelles in Trypanosoma brucei.

    Science.gov (United States)

    Gheiratmand, Ladan; Brasseur, Anais; Zhou, Qing; He, Cynthia Y

    2013-02-01

    Trypanosoma brucei, a unicellular parasite, contains several single-copied organelles that duplicate and segregate in a highly coordinated fashion during the cell cycle. In the procyclic stage, a bi-lobed structure is found adjacent to the single ER exit site and Golgi apparatus, forming both stable and dynamic association with other cytoskeletal components including the basal bodies that seed the flagellum and the flagellar pocket collar that is critical for flagellar pocket biogenesis. To further understand the bi-lobe and its association with adjacent organelles, we performed proteomic analyses on the immunoisolated bi-lobe complex. Candidate proteins were localized to the flagellar pocket, the basal bodies, a tripartite attachment complex linking the basal bodies to the kinetoplast, and a segment of microtubule quartet linking the flagellar pocket collar and bi-lobe to the basal bodies. These results supported an extensive connection among the single-copied organelles in T. brucei, a strategy employed by the parasite for orderly organelle assembly and inheritance during the cell cycle.

  4. Single-incision video-assisted thoracoscopic surgery left-lower lobe anterior segmentectomy (S8).

    Science.gov (United States)

    Galvez, Carlos; Lirio, Francisco; Sesma, Julio; Baschwitz, Benno; Bolufer, Sergio

    2017-01-01

    Unusual anatomical segmentectomies are technically demanding procedures that require a deep knowledge of intralobar anatomy and surgical skill. In the other hand, these procedures preserve more normal lung parenchyma for lesions located in specific anatomical segments, and are indicated for benign lesions, metastasis and also early stage adenocarcinomas without nodal involvement. A 32-year-old woman was diagnosed of a benign pneumocytoma in the anterior segment of the left-lower lobe (S8, LLL), so we performed a single-incision video-assisted thoracoscopic surgery (SI-VATS) anatomical S8 segmentectomy in 140 minutes under intercostal block. There were no intraoperative neither postoperative complications, the chest tube was removed at 24 hours and the patient discharged at 5 th postoperative day with low pain on the visual analogue scale (VAS). Final pathologic exam reported a benign sclerosant pneumocytoma with free margins. The patient has recovered her normal activities at 3 months completely with radiological normal controls at 1 and 3 months.

  5. Caudate lobe resections: a single-center experience and evaluation of factors predictive of outcomes

    OpenAIRE

    Philips, Prejesh; Farmer, Russell W; Scoggins, Charles R; McMasters, Kelly M; Martin, Robert CG

    2013-01-01

    Background Despite the increasing frequency of liver resection for multiple types of disease, caudate lobe resection remains a rare surgical event. The goal of this study is to review our experience and evaluate possible predictors of adverse outcomes in patients undergoing caudate lobectomy. Methods We reviewed a 1,900-patient prospective hepato-pancreatico-biliary database from January 2000 to December 2011, identifying 36 hepatectomy patients undergoing caudate lobe resection. Clinicopatho...

  6. Single photon emission photography/magnetic resonance imaging (SPECT/MRI) visualization for frontal-lobe-damaged regions

    Science.gov (United States)

    Stokking, Rik; Zuiderveld, Karel J.; Hulshoff Pol, Hilleke E.; Viergever, Max A.

    1994-09-01

    We present multi-modality visualization strategies to convey information contained in registered Single Photon Emission Photography (SPECT) and Magnetic Resonance (MR) images of the brain. Multi-modality visualization provides a means to retrieve valuable information from the data which might otherwise remain obscured. Here we use MRI as an anatomical framework for functional information acquired with SPECT. This is part of clinical research studying the change of functionality caused by a frontal lobe damaged region. A number of known and newly developed techniques for the integrated visualization of SPECT and MR images will be discussed.

  7. New experimental model for single liver lobe hyperthermia in small animals using non-directional microwaves.

    Directory of Open Access Journals (Sweden)

    Ionuț Tudorancea

    Full Text Available Our aim was to develop a new experimental model for in vivo hyperthermia using non-directional microwaves, applicable to small experimental animals. We present an affordable approach for targeted microwave heat delivery to an isolated liver lobe in rat, which allows rapid, precise and stable tissue temperature control.A new experimental model is proposed. We used a commercial available magnetron generating 2450 MHz, with 4.4V and 14A in the filament and 4500V anodic voltage. Modifications were required in order to adjust tissue heating such as to prevent overheating and to allow for fine adjustments according to real-time target temperature. The heating is controlled using a virtual instrument application implemented in LabView® and responds to 0.1° C variations in the target. Ten healthy adult male Wistar rats, weighing 250-270 g were used in this study. The middle liver lobe was the target for controlled heating, while the rest of the living animal was protected.In vivo microwave delivery using our experimental setting is safe for the animals. Target tissue temperature rises from 30°C to 40°C with 3.375°C / second (R2 = 0.9551, while the increment is lower it the next two intervals (40-42°C and 42-44°C with 0.291°C/ s (R2 = 0.9337 and 0.136°C/ s (R2 = 0.7894 respectively, when testing in sequences. After reaching the desired temperature, controlled microwave delivery insures a very stable temperature during the experiments.We have developed an inexpensive and easy to manufacture system for targeted hyperthermia using non-directional microwave radiation. This system allows for fine and stable temperature adjustments within the target tissue and is ideal for experimental models testing below or above threshold hyperthermia.

  8. Cognitive Impairment in Temporal Lobe Epilepsy: Role of Online and Offline Processing of Single Cell Information

    Science.gov (United States)

    Titiz, A. S.; Mahoney, J. M.; Testorf, M. E.; Holmes, G. L.; Scott, R. C.

    2014-01-01

    Cognitive impairment is a common comorbidity in temporal lobe epilepsy (TLE) and is often considered more detrimental to quality of life than seizures. While it has been previously shown that the encoding of memory during behavior is impaired in the pilocarpine model of TLE in rats, how this information is consolidated during the subsequent sleep period remains unknown. In this study, we first report marked deficits in spatial memory performance and severe cell loss in the CA1 layer of the hippocampus lower spatial coherence of firing in TLE rats. We then present the first evidence that the reactivation of behavior-driven patterns of activity of CA1 place cells in the hippocampus is intact in TLE rats. Using a template-matching method, we discovered that real-time (3–5 s) reactivation structure was intact in TLE rats. Furthermore, we estimated the entropy rate of short time scale (~250 ms) bursting activity using block entropies and found that significant, extended temporal correlations exist in both TLE and Control rats. Fitting a first order Markov Chain model to these bursting time series, we found that long sequences derived from behavior were significantly enriched in the Markov model over corresponding models fit on randomized data confirming the presence of replay in shorter time scales. We propose that the persistent consolidation of poor spatial information in both real-time and during bursting activity may contribute to memory impairments in TLE rats. PMID:24799359

  9. A multicenter reproducibility study of single-voxel {sup 1}H-MRS of the medial temporal lobe

    Energy Technology Data Exchange (ETDEWEB)

    Traeber, Frank; Block, Wolfgang; Guer, Okan; Schild, Hans H. [University of Bonn, Department of Radiology, Bonn (Germany); Freymann, Nikolaus; Heun, Reinhard; Jessen, Frank [University of Bonn, Department of Psychiatry, Bonn (Germany); Kucinski, Thomas [University of Hamburg, Department of Neuroradiology, Hamburg (Germany); Hammen, Thilo [University of Erlangen, Department of Psychiatry, Erlangen (Germany); Ende, Gabriele [Central Institute of Mental Health, NMR Research in Psychiatry, Mannheim (Germany); Pilatus, Ulrich [University of Frankfurt, Department of Neuroradiology, Frankfurt (Germany); Hampel, Harald [University of Munich, Department of Psychiatry, Munich (Germany)

    2006-05-15

    Proton magnetic resonance spectroscopy ({sup 1}H-MRS) has provided evidence for a reduction of N-acetyl-aspartate (NAA) in the medial temporal lobe (MTL) in cerebral disorders such as Alzheimer's Disease. Within the {sup 1}H-MRS study of the German Research Network on Dementia, we determined the multicenter reproducibility of single-voxel {sup 1}H-MRS of the MTL. At five sites with 1.5T MR systems, single-voxel {sup 1}H spectra from the MTL of an identical healthy subject were measured. The same subject was also examined at one of the sites five times to assess intracenter stability. The protocol included water-suppressed spectra with TE 272 ms and TE 30 ms and unsuppressed spectra for absolute quantification of metabolite concentrations. The intracenter reproducibility of absolute NAA concentration, expressed as coefficient of variation (CV), was 1.8%. CV for the concentrations of creatine (Cr), choline (Cho), and myoinositol (MI) and for the ratios NAA/Cr, NAA/Cho, and MI/NAA varied by 11-16%. Intercenter CV was 3.9% for NAA and were below 10% for all other metabolites and metabolic ratios. Our study demonstrates that quantitative assessment of NAA with single-voxel MRS can be performed with high intercenter reproducibility. This is the basis for applying {sup 1}H-MRS in large-scale early recognition and treatment studies in MTL affecting disorders. (orig.)

  10. A multicenter reproducibility study of single-voxel 1H-MRS of the medial temporal lobe

    International Nuclear Information System (INIS)

    Traeber, Frank; Block, Wolfgang; Guer, Okan; Schild, Hans H.; Freymann, Nikolaus; Heun, Reinhard; Jessen, Frank; Kucinski, Thomas; Hammen, Thilo; Ende, Gabriele; Pilatus, Ulrich; Hampel, Harald

    2006-01-01

    Proton magnetic resonance spectroscopy ( 1 H-MRS) has provided evidence for a reduction of N-acetyl-aspartate (NAA) in the medial temporal lobe (MTL) in cerebral disorders such as Alzheimer's Disease. Within the 1 H-MRS study of the German Research Network on Dementia, we determined the multicenter reproducibility of single-voxel 1 H-MRS of the MTL. At five sites with 1.5T MR systems, single-voxel 1 H spectra from the MTL of an identical healthy subject were measured. The same subject was also examined at one of the sites five times to assess intracenter stability. The protocol included water-suppressed spectra with TE 272 ms and TE 30 ms and unsuppressed spectra for absolute quantification of metabolite concentrations. The intracenter reproducibility of absolute NAA concentration, expressed as coefficient of variation (CV), was 1.8%. CV for the concentrations of creatine (Cr), choline (Cho), and myoinositol (MI) and for the ratios NAA/Cr, NAA/Cho, and MI/NAA varied by 11-16%. Intercenter CV was 3.9% for NAA and were below 10% for all other metabolites and metabolic ratios. Our study demonstrates that quantitative assessment of NAA with single-voxel MRS can be performed with high intercenter reproducibility. This is the basis for applying 1 H-MRS in large-scale early recognition and treatment studies in MTL affecting disorders. (orig.)

  11. Dose painting to treat single-lobe prostate cancer with hypofractionated high-dose radiation using targeted external beam radiation: Is it feasible?

    International Nuclear Information System (INIS)

    Amini, Arya; Westerly, David C.; Waxweiler, Timothy V.; Ryan, Nicole; Raben, David

    2015-01-01

    Targeted focal therapy strategies for treating single-lobe prostate cancer are under investigation. In this planning study, we investigate the feasibility of treating a portion of the prostate to full-dose external beam radiation with reduced dose to the opposite lobe, compared with full-dose radiation delivered to the entire gland using hypofractionated radiation. For 10 consecutive patients with low- to intermediate-risk prostate cancer, 2 hypofractionated, single-arc volumetric-modulated arc therapy (VMAT) plans were designed. The first plan (standard hypofractionation regimen [STD]) included the entire prostate gland, treated to 70 Gy delivered in 28 fractions. The second dose painting plan (DP) encompassed the involved lobe treated to 70 Gy delivered in 28 fractions, whereas the opposing, uninvolved lobe received 50.4 Gy in 28 fractions. Mean dose to the opposing neurovascular bundle (NVB) was considerably lower for DP vs STD, with a mean dose of 53.9 vs 72.3 Gy (p < 0.001). Mean penile bulb dose was 18.6 Gy for DP vs 19.2 Gy for STD (p = 0.880). Mean rectal dose was 21.0 Gy for DP vs 22.8 Gy for STD (p = 0.356). Rectum V 70 (the volume receiving ≥70 Gy) was 2.01% for DP vs 2.74% for STD (p = 0.328). Bladder V 70 was 1.69% for DP vs 2.78% for STD (p = 0.232). Planning target volume (PTV) maximum dose points were 76.5 and 76.3 Gy for DP and STD, respectively (p = 0.760). This study demonstrates the feasibility of using VMAT for partial-lobe prostate radiation in patients with prostate cancer involving 1 lobe. Partial-lobe prostate plans appeared to spare adjacent critical structures including the opposite NVB

  12. Spatial filtering nearly eliminates the side-lobes in single- and multi-photon 4pi-type-C super-resolution fluorescence microscopy

    Science.gov (United States)

    Kavya, M.; Regmi, Raju; Mondal, Partha P.

    2013-09-01

    Super-resolution microscopy has tremendously progressed our understanding of cellular biophysics and biochemistry. Specifically, 4pi fluorescence microscopy technique stands out because of its axial super-resolution capability. All types of 4pi-microscopy techniques work well in conjugation with deconvolution techniques to get rid of artifacts due to side-lobes. In this regard, we propose a technique based on spatial filter in a 4pi-type-C confocal setup to get rid of these artifacts. Using a special spatial filter, we have reduced the depth-of-focus. Interference of two similar depth-of-focus beams in a 4π geometry result in substantial reduction of side-lobes. Studies show a reduction of side-lobes by 46% and 76% for single and two photon variant compared to 4pi - type - C confocal system. This is incredible considering the resolving capability of the existing 4pi - type - C confocal microscopy. Moreover, the main lobe is found to be 150 nm for the proposed spatial filtering technique as compared to 690 nm of the state-of-art confocal system. Reconstruction of experimentally obtained 2PE - 4pi data of green fluorescent protein (GFP)-tagged mitocondrial network shows near elimination of artifacts arising out of side-lobes. Proposed technique may find interesting application in fluorescence microscopy, nano-lithography, and cell biology.

  13. Far-Field Fluorescence Nanoscopy

    Science.gov (United States)

    Hell, Stefan

    2009-03-01

    The resolution of a far-field optical microscopy is usually limited to d=λ/ λ( 2,α ) . - ( 2,α ) > 200 nm, with nα denoting the numerical aperture of the lens and λ the wavelength of light. While the diffraction barrier has prompted the invention of electron, scanning probe, and x-ray microscopy, the 3D-imaging of the interior of (live) cells requires the use of focused visible light. I will discuss new developments of optical microscopy that I anticipate to have a lasting impact on our understanding of living matter. Emphasis will be placed on physical concepts that have overcome the diffraction barrier in far-field fluorescence microscopy. To set the scene for future directions, I will show that all these concepts share a common strategy: exploiting selected states and transitions of the fluorescent marker to neutralize the limiting role of diffraction. The first viable concept of this kind was Stimulated Emission Depletion (STED) microscopy where the spot diameter followsd λ/ λ( 2,α√1+I / I Is . - Is ) . - ( 2,α√1+I / I Is . - Is ); I / I Is . - Isis a measure of the strength with which the molecule is send from the fluorescent state to the dark ground state. For I / I Is . - Is->∞ it follows that d->0, meaning that the resolution that can, in principle, be molecular. The concept underlying STED microscopy can be expanded by employing other transitions that shuffle the molecule between a dark and a bright state, such as (i) shelving the fluorophore in a dark triplet state, and (ii) photoswitching between a `fluorescence activated' and a `fluorescence deactivated' conformational state. Examples for the latter include photochromic organic compounds, and fluorescent proteins which undergo a cis-trans photoisomerizations. Photoswitching provides ultrahigh resolution at ultralow light levels. Switching can be performed in an ensemble or individually in which case the image is assembled molecule by molecule at high resolution. By providing molecular

  14. Far-field optical nanoscopy.

    Science.gov (United States)

    Hell, Stefan W

    2007-05-25

    In 1873, Ernst Abbe discovered what was to become a well-known paradigm: the inability of a lens-based optical microscope to discern details that are closer together than half of the wavelength of light. However, for its most popular imaging mode, fluorescence microscopy, the diffraction barrier is crumbling. Here, I discuss the physical concepts that have pushed fluorescence microscopy to the nanoscale, once the prerogative of electron and scanning probe microscopes. Initial applications indicate that emergent far-field optical nanoscopy will have a strong impact in the life sciences and in other areas benefiting from nanoscale visualization.

  15. Effect of partial volume correction on muscarinic cholinergic receptor imaging with single-photon emission tomography in patients with temporal lobe epilepsy

    International Nuclear Information System (INIS)

    Weckesser, M.; Ziemons, K.; Griessmeier, M.; Sonnenberg, F.; Langen, K.J.; Mueller-Gaertner, H.W.; Hufnagel, A.; Elger, C.E.; Hacklaender, T.; Holschbach, M.

    1997-01-01

    Animal experiments and preliminary results in humans have indicated alterations of hippocampal muscarinic acetylcholine receptors (mAChR) in temporal lobe epilepsy. Patients with temporal lobe epilepsy often present with a reduction in hippocampal volume. The aim of this study was to investigate the influence of hippocampal atrophy on the quantification of mAChR with single photon emission tomography (SPET) in patients with temporal lobe epilepsy. Cerebral uptake of the muscarinic cholinergic antagonist [ 123 I]4-iododexetimide (IDex) was investigated by SPET in patients suffering from temporal lobe epilepsy of unilateral (n=6) or predominantly unilateral (n=1) onset. Regions of interest were drawn on co-registered magnetic resonance images. Hippocampal volume was determined in these regions and was used to correct the SPET results for partial volume effects. A ratio of hippocampal IDex binding on the affected side to that on the unaffected side was used to detect changes in muscarinic cholinergic receptor density. Before partial volume correction a decrease in hippocampal IDex binding on the focus side was found in each patient. After partial volume no convincing differences remained. Our results indicate that the reduction in hippocampal IDex binding in patients with epilepsy is due to a decrease in hippocampal volume rather than to a decrease in receptor concentration. (orig.). With 2 figs., 2 tabs

  16. A segmentectomy of the right upper lobe has an advantage over a right upper lobectomy regarding the preservation of the functional volume of the right middle lobe. Analysis by perfusion single-photon emission computed tomography/computed tomography

    International Nuclear Information System (INIS)

    Yoshimoto, Kentaro; Nomori, Hiroaki; Mori, Takeshi; Ohba, Yasuomi; Shibata, Hidekatsu; Tashiro, Kuniyuki; Shiraishi, Shinya; Kobayashi, Toshiaki

    2010-01-01

    To evaluate the advantages of a segmentectomy of the right upper lobe (RUL) over a right upper (RU) lobectomy regarding the preservation of the functional volume of the right middle lobe (RML), the postoperative forced expiratory volume in one second (FEV 1 ) of the RML was compared between an RU lobectomy and an RUL segmentectomy, by using a coregistered perfusion single-photon emission computed tomography and computed tomography (SPECT/CT). The pulmonary function tests and perfusion SPECT/CT were conducted before and after surgery (RU lobectomy: 7; RUL segmentectomy: 13). The FEV 1 of the RML before and after surgery was calculated from the data of the pulmonary function test and SPECT/CT. In the RU lobectomy group, the percentage change of FEV 1 was 71%±12%, which was significantly lower in comparison to 92%±9% in the RUL segmentectomy group (P=0.001). In the lobectomy group, the preoperative FEV 1 of the RML was 0.17±0.101 which decreased significantly to 0.06±0.061 after surgery (P=0.009). In the segmentectomy group, FEV 1 of the RML before and after the surgery were 0.23±0.101 and 0.20±0.111, of which the difference was not significant. An RUL segmentectomy has an advantage over an RU lobectomy regarding the preservation of pulmonary function, due to a greater preservation of not only the lung tissue, but also the FEV 1 of the RML. (author)

  17. [A case of pulmonary dirofilariasis with a single nodule on an apical lesion of the right upper lobe].

    Science.gov (United States)

    Hijikata, Naoya; Asanuma, Kouzo; Sato, Shintaro; Harasawa, Keiji; Miyaoka, Keisuke; Ishizu, Hideki

    2011-01-01

    A 75-year-old man with chronic gastritis and gastro-esophageal regurgitation syndrome was admitted to our hospital complaining of continuous productive cough, and an abnormal shadow was noted on a chest X-ray film. Chest computed tomography revealed a nodule 2.8 cm in diameter with a regular margin on the right apex. Fiberoptic bronchoscopy was performed, but did not yield a definitive diagnosis. We suspected primary lung cancer, and therefore, lung partial resection was performed under thoracoscopic surgery. The intraoperative pathological findings revealed inflammatory granuloma with necrosis, and pulmonary dirofilariasis was finally diagnosed. Pulmonary dirofilariasis is an important differential diagnosis in elderly patients with a chest abnormal nodular shadow. Lesions have been reportedly observed in the peripheral portion of the right lower lobe in many previous reports. However, in this case, a nodular lesion was noted in the right apex.

  18. Monoamine oxidase B single-photon emission tomography with [123I]Ro 43-0463: imaging in volunteers and patients with temporal lobe epilepsy

    International Nuclear Information System (INIS)

    Buck, A.; Frey, L.D.; Blaeuenstein, P.; Schubiger, P.; Kraemer, G.; Siegel, A.; Weber, B.; Wieser, H.G.

    1998-01-01

    Imaging of monoamine oxidase of subtype B (MAO B) is of interest in various neurological diseases. In the past non-invasive assessment of MAO B has only been possible with positron emission tomography (PET) ligands. Given the limited availability of PET, a single-photon emission tomography (SPET) ligand would be desirable. In this study SPET imaging with the new MAO B inhibitor [ 123 I]Ro 43-0463 was performed in five volunteers and nine patients with temporal lobe epilepsy (TLE). In two volunteers a second study was performed 12 h following blockade with deprenyl. In the TLE patients the tracer was administered as bolus (n = 4) or as prolonged infusion (n = 5). The regional uptake pattern correlated well with the known distribution of MAO B. In the two blocking studies ligand uptake was substantially reduced compared with baseline. In the TLE patients increased uptake was found in the ipsilateral mesial temporal lobe and, surprisingly, in the ipsilateral putamen. This study indicates the potential of the new SPET ligand [ 123 I]Ro 43-0463 to map MAO B concentration in the human brain. The new finding of increased MAO B in the putamen of TLE patients needs further studies to elucidate its exact pathophysiology. (orig.)

  19. Far-Field Voice Activity Detection and Its Applications in Adverse Acoustic Environments

    DEFF Research Database (Denmark)

    Petsatodis, Theodoros

    2012-01-01

    phones, VOIP terminals) and research environments (smart rooms), a multiple microphone VAD is also considered. The system processes signals captured by far-field sensors in order to integrate spatial information in addition to the frequency content available at a single sensor. The core of the system...

  20. Topological sensitivity based far-field detection of elastic inclusions

    Science.gov (United States)

    Abbas, Tasawar; Khan, Shujaat; Sajid, Muhammad; Wahab, Abdul; Ye, Jong Chul

    2018-03-01

    The aim of this article is to present and rigorously analyze topological sensitivity based algorithms for detection of diametrically small inclusions in an isotropic homogeneous elastic formation using single and multiple measurements of the far-field scattering amplitudes. A L2 -cost functional is considered and a location indicator is constructed from its topological derivative. The performance of the indicator is analyzed in terms of the topological sensitivity for location detection and stability with respect to measurement and medium noises. It is established that the location indicator does not guarantee inclusion detection and achieves only a low resolution when there is mode-conversion in an elastic formation. Accordingly, a weighted location indicator is designed to tackle the mode-conversion phenomenon. It is substantiated that the weighted function renders the location of an inclusion stably with resolution as per Rayleigh criterion.

  1. Frontal lobe function in temporal lobe epilepsy

    Science.gov (United States)

    Stretton, J.; Thompson, P.J.

    2012-01-01

    Summary Temporal lobe epilepsy (TLE) is typically associated with long-term memory dysfunction. The frontal lobes support high-level cognition comprising executive skills and working memory that is vital for daily life functioning. Deficits in these functions have been increasingly reported in TLE. Evidence from both the neuropsychological and neuroimaging literature suggests both executive function and working memory are compromised in the presence of TLE. In relation to executive impairment, particular focus has been paid to set shifting as measured by the Wisconsin Card Sorting Task. Other discrete executive functions such as decision-making and theory of mind also appear vulnerable but have received little attention. With regard to working memory, the medial temporal lobe structures appear have a more critical role, but with emerging evidence of hippocampal dependent and independent processes. The relative role of underlying pathology and seizure spread is likely to have considerable bearing upon the cognitive phenotype and trajectory in TLE. The identification of the nature of frontal lobe dysfunction in TLE thus has important clinical implications for prognosis and surgical management. Longitudinal neuropsychological and neuroimaging studies assessing frontal lobe function in TLE patients pre- and postoperatively will improve our understanding further. PMID:22100147

  2. Imaging memory in temporal lobe epilepsy: predicting the effects of temporal lobe resection.

    Science.gov (United States)

    Bonelli, Silvia B; Powell, Robert H W; Yogarajah, Mahinda; Samson, Rebecca S; Symms, Mark R; Thompson, Pamela J; Koepp, Matthias J; Duncan, John S

    2010-04-01

    Functional magnetic resonance imaging can demonstrate the functional anatomy of cognitive processes. In patients with refractory temporal lobe epilepsy, evaluation of preoperative verbal and visual memory function is important as anterior temporal lobe resections may result in material specific memory impairment, typically verbal memory decline following left and visual memory decline after right anterior temporal lobe resection. This study aimed to investigate reorganization of memory functions in temporal lobe epilepsy and to determine whether preoperative memory functional magnetic resonance imaging may predict memory changes following anterior temporal lobe resection. We studied 72 patients with unilateral medial temporal lobe epilepsy (41 left) and 20 healthy controls. A functional magnetic resonance imaging memory encoding paradigm for pictures, words and faces was used testing verbal and visual memory in a single scanning session on a 3T magnetic resonance imaging scanner. Fifty-four patients subsequently underwent left (29) or right (25) anterior temporal lobe resection. Verbal and design learning were assessed before and 4 months after surgery. Event-related functional magnetic resonance imaging analysis revealed that in left temporal lobe epilepsy, greater left hippocampal activation for word encoding correlated with better verbal memory. In right temporal lobe epilepsy, greater right hippocampal activation for face encoding correlated with better visual memory. In left temporal lobe epilepsy, greater left than right anterior hippocampal activation on word encoding correlated with greater verbal memory decline after left anterior temporal lobe resection, while greater left than right posterior hippocampal activation correlated with better postoperative verbal memory outcome. In right temporal lobe epilepsy, greater right than left anterior hippocampal functional magnetic resonance imaging activation on face encoding predicted greater visual memory decline

  3. Spectrally resolved far-fields of terahertz quantum cascade lasers

    OpenAIRE

    Brandstetter, Martin; Schönhuber, Sebastian; Krall, Michael; Kainz, Martin A.; Detz, Hermann; Zederbauer, Tobias; Andrews, Aaron M.; Strasser, Gottfried; Unterrainer, Karl

    2016-01-01

    We demonstrate a convenient and fast method to measure the spectrally resolved far-fields of multimode terahertz quantum cascade lasers by combining a microbolometer focal plane array with an FTIR spectrometer. Far-fields of fundamental TM0 and higher lateral order TM1 modes of multimode Fabry-P\\'erot type lasers have been distinguished, which very well fit to the results obtained by a 3D finite-element simulation. Furthermore, multimode random laser cavities have been investigated, analyzing...

  4. Temporal Lobe Seizure

    Science.gov (United States)

    ... pregnancy Temporal lobe seizure Symptoms & causes Diagnosis & treatment Advertisement Mayo Clinic does not endorse companies or products. ... a Job Site Map About This Site Twitter Facebook Google YouTube Pinterest Mayo Clinic is a not- ...

  5. Super-Planckian far-field radiative heat transfer

    Science.gov (United States)

    Fernández-Hurtado, V.; Fernández-Domínguez, A. I.; Feist, J.; García-Vidal, F. J.; Cuevas, J. C.

    2018-01-01

    We present here a theoretical analysis that demonstrates that the far-field radiative heat transfer between objects with dimensions smaller than the thermal wavelength can overcome the Planckian limit by orders of magnitude. To guide the search for super-Planckian far-field radiative heat transfer, we make use of the theory of fluctuational electrodynamics and derive a relation between the far-field radiative heat transfer and the directional absorption efficiency of the objects involved. Guided by this relation, and making use of state-of-the-art numerical simulations, we show that the far-field radiative heat transfer between highly anisotropic objects can largely overcome the black-body limit when some of their dimensions are smaller than the thermal wavelength. In particular, we illustrate this phenomenon in the case of suspended pads made of polar dielectrics like SiN or SiO2. These structures are widely used to measure the thermal transport through nanowires and low-dimensional systems and can be employed to test our predictions. Our work illustrates the dramatic failure of the classical theory to predict the far-field radiative heat transfer between micro- and nanodevices.

  6. Neocortical Temporal Lobe Epilepsy

    Science.gov (United States)

    Bercovici, Eduard; Kumar, Balagobal Santosh; Mirsattari, Seyed M.

    2012-01-01

    Complex partial seizures (CPSs) can present with various semiologies, while mesial temporal lobe epilepsy (mTLE) is a well-recognized cause of CPS, neocortical temporal lobe epilepsy (nTLE) albeit being less common is increasingly recognized as separate disease entity. Differentiating the two remains a challenge for epileptologists as many symptoms overlap due to reciprocal connections between the neocortical and the mesial temporal regions. Various studies have attempted to correctly localize the seizure focus in nTLE as patients with this disorder may benefit from surgery. While earlier work predicted poor outcomes in this population, recent work challenges those ideas yielding good outcomes in part due to better localization using improved anatomical and functional techniques. This paper provides a comprehensive review of the diagnostic workup, particularly the application of recent advances in electroencephalography and functional brain imaging, in neocortical temporal lobe epilepsy. PMID:22953057

  7. Tsunami inversion for sea surface displacement using far-field DART data of the 2011 Tohoku earthquake

    Science.gov (United States)

    Ho, T.; Satake, K.

    2016-12-01

    We re-examined the 2011 Tohoku tsunami with far-field DART data, which had not been used in previous tsunami source studies. Our results show that the location of maximum sea surface displacement is shifted by adding the far-field data. Although we have abundant near-field tsunami observations for the 2011 Tohoku earthquake, the far-field data are still important for acquiring a good azimuthal coverage. Tsunami waveforms with travel time delay and phase reversal have been recorded from distant tsunamis. This made far-field waveforms unused in inversion. To solve those problems, the phase correction method proposed by Watada et al. (2014, JGR) is applied. Their method converts the tsunami waveforms of linear long wave into dispersive waveforms which accounts for the effects of elastic tsunami loadings on the Earth, compression of seawater, and gravitational potential change associated with tsunami propagation. We set four different combinations of stations in our inversion. Scheme "NS" uses only near-field stations. "DS" includes only near- and far-field DART stations, and scheme "OS" adds seven near-field Japanese OBP-type stations to DS. All available stations are used in "AS." Both single and multiple time window inversions are performed. The results show that the maximum displacement appears between the epicenter and trench rather than on the trench after we added the far-field data. To further examine the inversion results, we performed forward simulations using the inverted models and compared the simulated waveforms with the observed waveforms by calculating their normalized root mean square misfit. Models from NS and AS both show good agreements with observed waveforms at near-field stations, but the model from AS fits better at far-field stations. The model from OS fits slightly better than AS at far-field stations. It is noteworthy that OS shows better agreement than AS and NS at some near-field non-OBP-type stations, which have not been used in the

  8. Microsurgical anatomy of the central lobe.

    Science.gov (United States)

    Frigeri, Thomas; Paglioli, Eliseu; de Oliveira, Evandro; Rhoton, Albert L

    2015-03-01

    The central lobe consists of the pre- and postcentral gyri on the lateral surface and the paracentral lobule on the medial surface and corresponds to the sensorimotor cortex. The objective of the present study was to define the neural features, craniometric relationships, arterial supply, and venous drainage of the central lobe. Cadaveric hemispheres dissected using microsurgical techniques provided the material for this study. The coronal suture is closer to the precentral gyrus and central sulcus at its lower rather than at its upper end, but they are closest at a point near where the superior temporal line crosses the coronal suture. The arterial supply of the lower two-thirds of the lateral surface of the central lobe was from the central, precentral, and anterior parietal branches that arose predominantly from the superior trunk of the middle cerebral artery. The medial surface and the superior third of the lateral surface were supplied by the posterior interior frontal, paracentral, and superior parietal branches of the pericallosal and callosomarginal arteries. The venous drainage of the superior two-thirds of the lateral surface and the central lobe on the medial surface was predominantly through the superior sagittal sinus, and the inferior third of the lateral surface was predominantly through the superficial sylvian veins to the sphenoparietal sinus or the vein of Labbé to the transverse sinus. The pre- and postcentral gyri and paracentral lobule have a morphological and functional anatomy that differentiates them from the remainder of their respective lobes and are considered by many as a single lobe. An understanding of the anatomical relationships of the central lobe can be useful in preoperative planning and in establishing reliable intraoperative landmarks.

  9. Mesial frontal lobe epilepsy.

    Science.gov (United States)

    Unnwongse, Kanjana; Wehner, Tim; Foldvary-Schaefer, Nancy

    2012-10-01

    Mesial frontal lobe epilepsies can be divided into epilepsies arising from the anterior cingulate gyrus and those of the supplementary sensorimotor area. They provide diagnostic challenges because they often lack lateralizing or localizing features on clinical semiology and interictal and ictal scalp electroencephalographic (EEG) recordings. A number of unique semiologic features have been described over the last decade in patients with mesial frontal lobe epilepsy (FLE). There are few reports of applying advanced neurophysiologic techniques such as electrical source imaging, magnetoencephalography, EEG/functional magnetic resonance imaging, or analysis of high-frequency oscillations in patients with mesial FLE. Despite these diagnostic challenges, it seems that patients with mesial FLE benefit from epilepsy surgery to the same extent or even better than patients with FLE do, as a whole.

  10. Plasmonic Devices for Near and Far-Field Applications

    KAUST Repository

    Alrasheed, Salma

    2017-11-30

    Plasmonics is an important branch of nanophotonics and is the study of the interaction of electromagnetic fields with the free electrons in a metal at metallic/dielectric interfaces or in small metallic nanostructures. The electric component of an exciting electromagnetic field can induce collective electron oscillations known as surface plasmons. Such oscillations lead to the localization of the fields that can be at sub-wavelength scale and to its significant enhancement relative to the excitation fields. These two characteristics of localization and enhancement are the main components that allow for the guiding and manipulation of light beyond the diffraction limit. This thesis focuses on developing plasmonic devices for near and far-field applications. In the first part of the thesis, we demonstrate the detection of single point mutation in peptides from multicomponent mixtures for early breast cancer detection using selfsimilar chain (SCC) plasmonic devices that show high field enhancement and localization. In the second part of this work, we investigate the anomalous reflection of light for TM polarization for normal and oblique incidence in the visible regime. We propose gradient phase gap surface plasmon (GSP) metasurfaces that exhibit high conversion efficiency (up to ∼97% of total reflected light) to the anomalous reflection angle for blue, green and red wavelengths at normal and oblique incidence. In the third part of the thesis, we present a theoretical approach to narrow the plasmon linewidth and enhance the near-field intensity at a plasmonic dimer gap (hot spot) through coupling the electric localized surface plasmon (LSP) resonance of a silver hemispherical dimer with the resonant modes of a Fabry-Perot (FP) cavity. In the fourth part of this work, we demonstrate numerically bright color pixels that are highly polarized and broadly tuned using periodic arrays of metal nanosphere dimers on a glass substrate. In the fifth and final part of the

  11. Dorsolateral frontal lobe epilepsy.

    Science.gov (United States)

    Lee, Ricky W; Worrell, Greg A

    2012-10-01

    Dorsolateral frontal lobe seizures often present as a diagnostic challenge. The diverse semiologies may not produce lateralizing or localizing signs and can appear bizarre and suggest psychogenic events. Unfortunately, scalp electroencephalographic (EEG) and magnetic resonance imaging (MRI) are often unsatisfactory. It is not uncommon that these traditional diagnostic studies are either unhelpful or even misleading. In some cases, SPECT and positron emission tomography imaging can be an effective tool to identify the origin of seizures. However, these techniques and other emerging techniques all have limitations, and new approaches are needed to improve source localization.

  12. Topological magnetoelectric effects in microwave far-field radiation

    Energy Technology Data Exchange (ETDEWEB)

    Berezin, M.; Kamenetskii, E. O.; Shavit, R. [Microwave Magnetic Laboratory, Department of Electrical and Computer Engineering, Ben Gurion University of the Negev, Beer Sheva (Israel)

    2016-07-21

    Similar to electromagnetism, described by the Maxwell equations, the physics of magnetoelectric (ME) phenomena deals with the fundamental problem of the relationship between electric and magnetic fields. Despite a formal resemblance between the two notions, they concern effects of different natures. In general, ME-coupling effects manifest in numerous macroscopic phenomena in solids with space and time symmetry breakings. Recently, it was shown that the near fields in the proximity of a small ferrite particle with magnetic-dipolar-mode (MDM) oscillations have the space and time symmetry breakings and the topological properties of these fields are different from the topological properties of the free-space electromagnetic fields. Such MDM-originated fields—called magnetoelectric (ME) fields—carry both spin and orbital angular momenta. They are characterized by power-flow vortices and non-zero helicity. In this paper, we report on observation of the topological ME effects in far-field microwave radiation based on a small microwave antenna with a MDM ferrite resonator. We show that the microwave far-field radiation can be manifested with a torsion structure where an angle between the electric and magnetic field vectors varies. We discuss the question on observation of the regions of localized ME energy in far-field microwave radiation.

  13. Action-at-a-distance metamaterials: Distributed local actuation through far-field global forces

    Science.gov (United States)

    Hedayati, R.; Mirzaali, M. J.; Vergani, L.; Zadpoor, A. A.

    2018-03-01

    Mechanical metamaterials are a sub-category of designer materials where the geometry of the material at the small-scale is rationally designed to give rise to unusual properties and functionalities. Here, we propose the concept of "action-at-a-distance" metamaterials where a specific pattern of local deformation is programmed into the fabric of (cellular) materials. The desired pattern of local actuation could then be achieved simply through the application of one single global and far-field force. We proposed graded designs of auxetic and conventional unit cells with changing Poisson's ratios as a way of making "action-at-a-distance" metamaterials. We explored five types of graded designs including linear, two types of radial gradients, checkered, and striped. Specimens were fabricated with indirect additive manufacturing and tested under compression, tension, and shear. Full-field strain maps measured with digital image correlation confirmed different patterns of local actuation under similar far-field strains. These materials have potential applications in soft (wearable) robotics and exosuits.

  14. Action-at-a-distance metamaterials: Distributed local actuation through far-field global forces

    Directory of Open Access Journals (Sweden)

    R. Hedayati

    2018-03-01

    Full Text Available Mechanical metamaterials are a sub-category of designer materials where the geometry of the material at the small-scale is rationally designed to give rise to unusual properties and functionalities. Here, we propose the concept of “action-at-a-distance” metamaterials where a specific pattern of local deformation is programmed into the fabric of (cellular materials. The desired pattern of local actuation could then be achieved simply through the application of one single global and far-field force. We proposed graded designs of auxetic and conventional unit cells with changing Poisson’s ratios as a way of making “action-at-a-distance” metamaterials. We explored five types of graded designs including linear, two types of radial gradients, checkered, and striped. Specimens were fabricated with indirect additive manufacturing and tested under compression, tension, and shear. Full-field strain maps measured with digital image correlation confirmed different patterns of local actuation under similar far-field strains. These materials have potential applications in soft (wearable robotics and exosuits.

  15. Dimorphic olfactory lobes in the arthropoda.

    Science.gov (United States)

    Strausfeld, Nicholas; Reisenman, Carolina E

    2009-07-01

    Specialized olfactory lobe glomeruli relating to sexual or caste differences have been observed in at least five orders of insects, suggesting an early appearance of this trait in insect evolution. Dimorphism is not limited to nocturnal species, but occurs even in insects that are known to use vision for courtship. Other than a single description, there is no evidence for similar structures occurring in the Crustacea, suggesting that the evolution of dimorphic olfactory systems may typify terrestrial arthropods.

  16. Temporal lobe epilepsy semiology.

    Science.gov (United States)

    Blair, Robert D G

    2012-01-01

    Epilepsy represents a multifaceted group of disorders divided into two broad categories, partial and generalized, based on the seizure onset zone. The identification of the neuroanatomic site of seizure onset depends on delineation of seizure semiology by a careful history together with video-EEG, and a variety of neuroimaging technologies such as MRI, fMRI, FDG-PET, MEG, or invasive intracranial EEG recording. Temporal lobe epilepsy (TLE) is the commonest form of focal epilepsy and represents almost 2/3 of cases of intractable epilepsy managed surgically. A history of febrile seizures (especially complex febrile seizures) is common in TLE and is frequently associated with mesial temporal sclerosis (the commonest form of TLE). Seizure auras occur in many TLE patients and often exhibit features that are relatively specific for TLE but few are of lateralizing value. Automatisms, however, often have lateralizing significance. Careful study of seizure semiology remains invaluable in addressing the search for the seizure onset zone.

  17. Optimization of Fixed Microphone Array in High Speed Train Noises Identification Based on Far-Field Acoustic Holography

    Directory of Open Access Journals (Sweden)

    Rujia Wang

    2017-01-01

    Full Text Available Acoustical holography has been widely applied for noise sources location and sound field measurement. Performance of the microphones array directly determines the sound source recognition method. Therefore, research is very important to the performance of the microphone array, its array of applications, selection, and how to design instructive. In this paper, based on acoustic holography moving sound source identification theory, the optimization method is applied in design of the microphone array, we select the main side lobe ratio and the main lobe area as the optimization objective function and then put the optimization method use in the sound source identification based on holography, and finally we designed this paper to optimize microphone array and compare the original array of equally spaced array with optimization results; by analyzing the optimization results and objectives, we get that the array can be achieved which is optimized not only to reduce the microphone but also to change objective function results, while improving the far-field acoustic holography resolving effect. Validation experiments have showed that the optimization method is suitable for high speed trains sound source identification microphone array optimization.

  18. Far-field super-resolution imaging of resonant multiples

    KAUST Repository

    Guo, Bowen

    2016-05-20

    We demonstrate for the first time that seismic resonant multiples, usually considered as noise, can be used for super-resolution imaging in the far-field region of sources and receivers. Tests with both synthetic data and field data show that resonant multiples can image reflector boundaries with resolutions more than twice the classical resolution limit. Resolution increases with the order of the resonant multiples. This procedure has important applications in earthquake and exploration seismology, radar, sonar, LIDAR (light detection and ranging), and ultrasound imaging, where the multiples can be used to make high-resolution images.

  19. Massive Temporal Lobe Cholesteatoma

    Directory of Open Access Journals (Sweden)

    Pasan Waidyasekara

    2015-01-01

    Full Text Available Introduction. Intracranial extension of cholesteatoma is rare. This may occur de novo or recur some time later either contiguous with or separate to the site of the original cholesteatoma. Presentation of Case. A 63-year-old female presented to a tertiary referral hospital with a fluctuating level of consciousness, fever, headache, and right-sided otorrhoea, progressing over several days. Her past medical history included surgery for right ear cholesteatoma and drainage of intracranial abscess 23 years priorly. There had been no relevant symptoms in the interim until 6 weeks prior to this presentation. Imaging demonstrated a large right temporal lobe mass contiguous with the middle ear and mastoid cavity with features consistent with cholesteatoma. The patient underwent a combined transmastoid/middle fossa approach for removal of the cholesteatoma and repair of the tegmen dehiscence. The patient made an uneventful recovery and remains well over 12 months later. Conclusion. This case presentation details a large intracranial cholesteatoma which had extended through a tegmen tympani dehiscence from recurrent right ear cholesteatoma treated by modified radical mastoidectomy over two decades priorly. There was a completely asymptomatic progression of disease until several weeks prior to this presentation.

  20. Sparse Matrix Motivated Reconstruction of Far-Field Radiation Patterns

    Science.gov (United States)

    2015-03-01

    Millennium Drive Suite 101 Belcamp, MD 21017 10. SPONSOR/MONITOR’S ACRONYM(S) 11. SPONSOR/MONITOR’S REPORT NUMBER(S) 12. DISTRIBUTION/AVAILABILITY...Fig. 13. Note the lack of back-lobe measurement due to the presence of the supporting tower . 14 Fig. 13 2-D radiation pattern of the

  1. Simulating the 1946 Aleutian far-field tsunami: The successful dislocation and the impossible landslide.

    Science.gov (United States)

    Hebert, H.; Okal, E. A.

    2004-12-01

    We present a final set of hydrodynamic simulations of the run-up of the 1946 Aleutian tsunami at the transpacific locations obtained during the field surveys taken in 1999-2001 by Okal et al. [2002]. As a source of the tsunami, we use both (i) a dislocation model based on the updated seismological study of Lopez and Okal [2002], which features slow bilateral rupture along a 200-km long fault zone; and (ii) the asymmetric dipolar source successfully used by Okal et al. [2003] to model the near-field run-up surveyed at Unimak Island. The simulations are carried out on a series of grids featuring fine scales both in the source area, and at the receiving shores (the latter up to a final scale of 50 m), but a coarser grid on the high seas. In general, the dislocation source does fit the run-up observations in the far-field, and in particular it reproduces the strong azimuthal directivity expected in the source geometry. This extends the ressults of Titov et al. (2001), who had modeled the inundation at Hilo on the basis of a similar dislocative source, but using a different numerical method. By contrast, the dipolar source produces absolute values of run-up ranging only from a few tens of cm to 3 m on the shorelines of the Marquesas and Juan Fernandez Islands, in all cases significantly less (by a factor of 3 to 5) than observed. We conclude that the near- and far-fields cannot be both modeled by a single source. The final model of the source of the 1946 Aleutian tsunami must be a composite betweem a very large, but very slow earthquake, responsible for the far field tsunami, and a landslide generating the devastating near-field tsunami.

  2. Far-field superresolution by imaging of resonance scattering

    KAUST Repository

    Schuster, Gerard T.

    2014-10-31

    We show that superresolution imaging in the far-field region of the sources and receivers is theoretically and practically possible if migration of resonant multiples is employed. A resonant multiple is one that bounces back and forth between two scattering points; it can also be the multiple between two smoothly varying interfaces as long as the reflection wave paths partially overlap and reflect from the same Fresnel zone. For a source with frequency f, compared to a one-way trip, N round trips in propagating between two scatterers increase the effective frequency by 2N × f and decrease the effective wavelength by λ/(2N). Thus, multiples can, in principle, be used as high-frequency probes to estimate detailed properties of layers. Tests with both synthetic and field data validate this claim. Improved resolution by multiple imaging is not only feasible for crustal reflections, but might be applicable to mantle and core reverberations recorded by earthquake seismologists.

  3. Memory reorganization following anterior temporal lobe resection: a longitudinal functional MRI study.

    Science.gov (United States)

    Bonelli, Silvia B; Thompson, Pamela J; Yogarajah, Mahinda; Powell, Robert H W; Samson, Rebecca S; McEvoy, Andrew W; Symms, Mark R; Koepp, Matthias J; Duncan, John S

    2013-06-01

    Anterior temporal lobe resection controls seizures in 50-60% of patients with intractable temporal lobe epilepsy but may impair memory function, typically verbal memory following left, and visual memory following right anterior temporal lobe resection. Functional reorganization can occur within the ipsilateral and contralateral hemispheres. We investigated the reorganization of memory function in patients with temporal lobe epilepsy before and after left or right anterior temporal lobe resection and the efficiency of postoperative memory networks. We studied 46 patients with unilateral medial temporal lobe epilepsy (25/26 left hippocampal sclerosis, 16/20 right hippocampal sclerosis) before and after anterior temporal lobe resection on a 3 T General Electric magnetic resonance imaging scanner. All subjects had neuropsychological testing and performed a functional magnetic resonance imaging memory encoding paradigm for words, pictures and faces, testing verbal and visual memory in a single scanning session, preoperatively and again 4 months after surgery. Event-related analysis revealed that patients with left temporal lobe epilepsy had greater activation in the left posterior medial temporal lobe when successfully encoding words postoperatively than preoperatively. Greater pre- than postoperative activation in the ipsilateral posterior medial temporal lobe for encoding words correlated with better verbal memory outcome after left anterior temporal lobe resection. In contrast, greater postoperative than preoperative activation in the ipsilateral posterior medial temporal lobe correlated with worse postoperative verbal memory performance. These postoperative effects were not observed for visual memory function after right anterior temporal lobe resection. Our findings provide evidence for effective preoperative reorganization of verbal memory function to the ipsilateral posterior medial temporal lobe due to the underlying disease, suggesting that it is the capacity

  4. Modern design of far-field target motion simulators

    Science.gov (United States)

    Hauser, Robin; Swamp, Michael; Havlicsek, Howard

    2006-05-01

    Target Motion Simulators (TMS) are often used in conjunction with Flight Motion Simulators (FMS) to provide a realistic simulation of tracking and target engagement. For near-field applications, the TMS has typically been implemented with two additional gimbals around the FMS. For far-field applications, such as a radar, the TMS has traditionally been implemented with curvilinear X-Y Frames. A curvilinear frame placed at the proper distance from the FMS has the benefit of always pointing the Target back to the FMS intersection of axes. In most cases the curvilinear TMS provides good results. However, the curvilinear TMS lacks the possibility to change the distance between Target and Seeker, which is needed for operation with different radar wavelengths. Acutronic has developed a new approach using a flat frame (X-Y) TMS coupled with a gimballed payload mount that has the possibility of being used at various distances without losing the functionality of continuous pointing back to the seeker. This paper describes the electro-mechanical design and gives an overview of the Computer and Controllers used. It further addresses the problem of coordination transformation that is needed to obtain the correct pointing.

  5. Far-field Diffraction Properties of Annular Walsh Filters

    Directory of Open Access Journals (Sweden)

    Pubali Mukherjee

    2013-01-01

    Full Text Available Annular Walsh filters are derived from the rotationally symmetric annular Walsh functions which form a complete set of orthogonal functions that take on values either +1 or −1 over the domain specified by the inner and outer radii of the annulus. The value of any annular Walsh function is taken as zero from the centre of the circular aperture to the inner radius of the annulus. The three values 0, +1, and −1 in an annular Walsh function can be realized in a corresponding annular Walsh filter by using transmission values of zero amplitude (i.e., an obscuration, unity amplitude and zero phase, and unity amplitude and phase, respectively. Not only the order of the Walsh filter but also the size of the inner radius of the annulus provides an additional degree of freedom in tailoring of point spread function by using these filters for pupil plane filtering in imaging systems. In this report, we present the far-field amplitude characteristics of some of these filters to underscore their potential for effective use in several demanding applications like high-resolution microscopy, optical data storage, microlithography, optical encryption, and optical micromanipulation.

  6. Brain SPECT imaging in temporal lobe epilepsy

    International Nuclear Information System (INIS)

    Krausz, Y.; Yaffe, S.; Atlan, H.; Cohen, D.; Konstantini, S.; Meiner, Z.

    1991-01-01

    Temporal lobe epilepsy is diagnosed by clinical symptoms and signs and by localization of an epileptogenic focus. A brain SPECT study of two patients with temporal lobe epilepsy, using 99m Tc-HMPAO, was used to demonstrate a perfusion abnormality in the temporal lobe, while brain CT and MRI were non-contributory. The electroencephalogram, though abnormal, did not localize the diseased area. The potential role of the SPECT study in diagnosis and localization of temporal lobe epilepsy is discussed. (orig.)

  7. Distally lobed integuments in some Angiosperm ovules

    NARCIS (Netherlands)

    Heel, van W.A.

    1970-01-01

    In this treatise ‘De l’Ovule’ Warming (1878) remarked that although the borders of the integuments grow uniformly, very rarely a division into lobes can be observed. He mentioned Symplocarpus foetida (inner integument four-lobed), Lagarosiphon schweinfurthii (outer integument four- or five-lobed)

  8. Historical Evolution of the Frontal Lobe Syndrome

    NARCIS (Netherlands)

    Krudop, W.A.; Pijnenburg, Y.A.L.

    2015-01-01

    The function of the frontal lobes and the related frontal lobe syndrome have not been described in detail until relatively late in history. Slowly, the combination of knowledge from animal models, the detailed examination of symptoms after traumatic frontal lobe injuries, and the rise and fall of

  9. Surgery for Temporal Lobe Epilepsy in Children

    Directory of Open Access Journals (Sweden)

    Mohammad Faraji-rad

    2017-12-01

    Full Text Available This study aimed to assess the efficacy of magnetic resonance imaging (MRI and single-photon emission computed tomography (SPECT in localizing epileptic foci in children with temporal lobe epilepsy (TLE. This prospective study was conducted on 12 patients including five males and seven females aged between 2 and 16 years old with a clinical diagnosis of TLE. All the patients underwent high-resolution MRI and if no abnormality was identified, SPECT was used for further assessment. In all the patients, visual inspection identified unilateral mesial temporal sclerosis, and the patients underwent craniotomy and lesionectomy.According to the results, eight patients were categorized in class I and two cases were classifies as class II, and all the patients survived. About 25% of the patients showed adequate memory function on the non-operated temporal lobe, and general intelligence quotient increased by 10% in 50% of the patients.According to the results, in patients with clinically suspected TLE, MRI alone is not able to localize the epileptic foci correctly, and SPECT can be helpful to localize these lesions.

  10. Temporal Lobe Epilepsy in Children

    Science.gov (United States)

    Nickels, Katherine C.; Wong-Kisiel, Lily C.; Moseley, Brian D.; Wirrell, Elaine C.

    2012-01-01

    The temporal lobe is a common focus for epilepsy. Temporal lobe epilepsy in infants and children differs from the relatively homogeneous syndrome seen in adults in several important clinical and pathological ways. Seizure semiology varies by age, and the ictal EEG pattern may be less clear cut than what is seen in adults. Additionally, the occurrence of intractable seizures in the developing brain may impact neurocognitive function remote from the temporal area. While many children will respond favorably to medical therapy, those with focal imaging abnormalities including cortical dysplasia, hippocampal sclerosis, or low-grade tumors are likely to be intractable. Expedient workup and surgical intervention in these medically intractable cases are needed to maximize long-term developmental outcome. PMID:22957247

  11. Radionuclide transport in the repository near-field and far-field

    International Nuclear Information System (INIS)

    Poteri, A.; Nordman, H.; Pulkkanen, V.-M.; Smith, P.

    2014-01-01

    This report is a background report of the TURVA-2012 safety case report 'Assessment of Radionuclide Release Scenarios for the Repository System'. This report gives a comprehensive account of the modelling of radionuclide release from a defective canister and the subsequent migration to the surface groundwater system. The focus of this report is in the radionuclide migration both in the repository near-field and in the repository far-field. Radionuclide releases from the canister and migration through the repository near-field and far-field have also been analysed in the probabilistic sensitivity analysis based on the Monte Carlo simulation method. Those simulations are discussed in a separate report by Cormenzana. Calculation cases are derived from three different types of scenarios: (i) The base scenario that assumes a single initially defective canister located in a cautiously selected canister position, i.e. selecting the failed canister location such that radionuclide release and transport properties are conservative compared to the statistics over all canister locations. Migration processes and parameter values follow the most likely lines of evolution. Repository safety functions are assumed to perform according to the design basis. Calculation cases defined in the Assessment of Radionuclide Release Scenarios report are also supplemented by additional calculation cases that are aimed to study variability between different DFN realisations (additional BS-ALL cases), longitudinal dispersion (BS-RC-ld cases) and alternative realisations of the transport classes along the release paths (BS-RC-tc cases), (ii) Variant scenarios that study declined performance of the repository safety functions. These include enhanced corrosion failure and degradation of the buffer under variant geochemical conditions (iii) Disturbance scenarios that analyse influences of unlikely events on the radionuclide release and migration. Analysis of the variant and disturbance scenarios

  12. Optimal placement of active braces by using PSO algorithm in near- and far-field earthquakes

    Science.gov (United States)

    Mastali, M.; Kheyroddin, A.; Samali, B.; Vahdani, R.

    2016-03-01

    One of the most important issues in tall buildings is lateral resistance of the load-bearing systems against applied loads such as earthquake, wind and blast. Dual systems comprising core wall systems (single or multi-cell core) and moment-resisting frames are used as resistance systems in tall buildings. In addition to adequate stiffness provided by the dual system, most tall buildings may have to rely on various control systems to reduce the level of unwanted motions stemming from severe dynamic loads. One of the main challenges to effectively control the motion of a structure is limitation in distributing the required control along the structure height optimally. In this paper, concrete shear walls are used as secondary resistance system at three different heights as well as actuators installed in the braces. The optimal actuator positions are found by using optimized PSO algorithm as well as arbitrarily. The control performance of buildings that are equipped and controlled using the PSO algorithm method placement is assessed and compared with arbitrary placement of controllers using both near- and far-field ground motions of Kobe and Chi-Chi earthquakes.

  13. Histopathologic variation between liver lobes in dogs.

    Science.gov (United States)

    Kemp, S D; Zimmerman, K L; Panciera, D L; Monroe, W E; Leib, M S

    2015-01-01

    Biopsy of the liver evaluates a small portion of tissue, with inferences made to the entire organ. The method and number of biopsies obtained are tempered by consideration of the risks and benefits. Recommendations often include biopsy of more than one liver lobe, although the consistency of histopathology among lobes in dogs is unknown. To describe the distribution of histopathologic abnormalities between liver lobes. We hypothesized that discordant results would be evenly distributed among all liver lobes. Seventy dogs undergoing necropsy. Prospective study. Liver samples were obtained from all lobes. A primary diagnosis was assigned to each liver sample based on the predominant histopathologic abnormality. In this population of dogs, biopsy of at least 2 liver lobes identified the predominant histologic abnormality in 98.6% of the cases. Ten (14%) of the dogs had ≤ 3 lobes in agreement and could not be assigned a predominant diagnosis. The same diagnosis was present in 6/6 lobes in 39 (56.5%) dogs, 5/6 lobes in 10 (14.5%) dogs, 4/6 lobes in 10 (14.5%) dogs, 3/6 lobes in 7 (10.1%) dogs, and 2/6 in 3 (4.3%) dogs. The number of discordant results did not differ between the liver lobes. The likelihood of obtaining a sample that is reflective of the predominant histologic abnormality in the liver is increased when multiple liver lobes are biopsied. Copyright © 2015 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals, Inc. on behalf of American College of Veterinary Internal Medicine.

  14. Patterns of verbal learning and memory in children with intractable temporal lobe or frontal lobe epilepsy.

    Science.gov (United States)

    Fuentes, Amanda; Smith, Mary Lou

    2015-12-01

    The objective of this study was to provide a better understanding of the verbal learning and memory (VLM) patterns that might differentiate children with frontal lobe epilepsy (FLE) from children with temporal lobe epilepsy (TLE) and to examine the impact of variables thought to influence outcomes (seizure laterality, age at seizure onset, age at assessment, epilepsy duration, number of antiepileptic drugs). Retrospective analyses were carried out for children with intractable unilateral TLE (n=100) and FLE (n=27) who completed standardized measures of VLM entailing lists of single words or lists of word pairs. Mean intelligent quotients and VLM scores on single words fell within the average range for both groups, whereas scores fell within the low average to borderline range on word pairs. No significant overall differences in VLM were found between the group with TLE and the group with FLE. Older age at assessment and older age at seizure onset were generally associated with better VLM in both groups but were related to better performance in a number of indices in the group with TLE and only fewer intrusions in the group with FLE. The VLM profiles of children with TLE and FLE are generally similar. Older age at assessment and older age at seizure onset have a favorable impact on both groups but are related to better encoding, retrieval, and monitoring processes for the group with TLE and improved memory monitoring (i.e., as indicated by fewer intrusions) in the group with FLE. Copyright © 2015 Elsevier Inc. All rights reserved.

  15. Combustion noise from gas turbine aircraft engines measurement of far-field levels

    Science.gov (United States)

    Krejsa, Eugene A.

    1987-01-01

    Combustion noise can be a significant contributor to total aircraft noise. Measurement of combustion noise is made difficult by the fact that both jet noise and combustion noise exhibit broadband spectra and peak in the same frequency range. Since in-flight reduction of jet noise is greater than that of combustion noise, the latter can be a major contributor to the in-flight noise of an aircraft but will be less evident, and more difficult to measure, under static conditions. Several methods for measuring the far-field combustion noise of aircraft engines are discussed in this paper. These methods make it possible to measure combustion noise levels even in situations where other noise sources, such as jet noise, dominate. Measured far-field combustion noise levels for several turbofan engines are presented. These levels were obtained using a method referred to as three-signal coherence, requiring that fluctuating pressures be measured at two locations within the engine core in addition to the far-field noise measurement. Cross-spectra are used to separate the far-field combustion noise from far-field noise due to other sources. Spectra and directivities are presented. Comparisons with existing combustion noise predictions are made.

  16. Far-field high resolution effects and manipulating of electromagnetic waves based on transformation optics

    Science.gov (United States)

    Ji, XueBin; Zang, XiaoFei; Li, Zhou; Shi, Cheng; Chen, Lin; Cai, Bin; Zhu, YiMing

    2015-05-01

    Based on the transformation optics (TO) and the effective medium theory (EMT), a new illusion media with homogeneous and isotropic materials is proposed to realize the far-field high resolution effects. When two point sources with the separation distance of λ0 / 4 are covered with the illusion media (λ0 is the free-space wavelength), the corresponding far-field pattern is equivalent to the case of two point sources with the separation distance larger than λ0 / 2 in free space, leading to the far-field high resolution effects (in free space, the separation distance of λ0 / 4 is less than half-wavelength, and thus the two point sources cannot be distinguished from each other). Furthermore, such illusion media can be applied to design tunable high-directivity antenna and an angle-dependent floating carpet cloak. Full wave simulations are carried out to verify the performance of our device.

  17. Effect of far-field flow on a columnar crystal in the convective undercooled melt

    Science.gov (United States)

    Ji, Xiao-Jian; Chen, Ming-Wen; Xu, Xiao-Hua; Wang, Zi-Dong

    2015-01-01

    The growth behavior of a columnar crystal in the convective undercooled melt affected by the far-field uniform flow is studied and the asymptotic solution for the interface evolution of the columnar crystal is derived by means of the asymptotic expansion method. The results obtained reveal that the far-field flow induces a significant change of the temperature around the columnar crystal and the convective flow caused by the far-field flow accelerates the growth velocity of the interface of the growing columnar crystal in the upstream direction and inhibits its growth velocity in the downstream direction. Our results are similar to the experimental data and numerical simulations. Project supported by the Overseas Distinguished Scholar Program by the Ministry of Education of China (Grant No. MS2010BJKJ005), the National Natural Science Foundation of China (Grant No. 10972030), and the Science and Technology Support Project of Jiangxi, China (Grant No. 20112BBE50006).

  18. Using a modified Hewlett Packard 8410 network analyzer as an automated farfield antenna range receiver

    Science.gov (United States)

    Terry, John D.; Kunath, Richard R.

    1990-01-01

    A Hewlett Packard 8410 Network Analyzer was modified to be used as an automated far-field antenna range receiver. By using external mixers, analog to digital signal conversion, and an external computer/controller, the HP8410 is capable of measuring signals as low as -110 dBm. The modified receiver is an integral part of an automated far-field range which features computer controlled test antenna positioning, system measurement parameters, and data acquisition, as well as customized measurement file management. The system described was assembled and made operational, taking advantage of off-the-shelf hardware available at minimal cost.

  19. Agenesis of the right lobe of liver

    International Nuclear Information System (INIS)

    Lee, Jeung Min; Kim, Chong Soo; Chung, Soo Hyun; Sohn, Myung Hee; Chung, Gyung Ho; Han, Young Min; Choi, Ki Chul; Cho, Baik Hwan

    1993-01-01

    Agenesis of the right lobe of the liver is a rear anomaly which may be associated with biliary stone disease, portal hypertension, and other congenital anomalies. The radiological differential diagnosis includes lobar atrophy due to cirrhosis or hilar cholangiocarcinoma. We present a case of agenesis of the right lobe the liver with characteristic clinical and radiological findings

  20. Accessory Lobes, Accessory Fissures and Prominent Papillary ...

    African Journals Online (AJOL)

    Often unreported hepatic variations include accessory fissures, lobes and processes. Variant hepatic fissures further show variations in location and depth. Accessory lobes of the liver have different size, shape, situation, connection with maternal organ. These abnormalities in the anatomy of human liver have the ...

  1. Frontal lobe alterations in schizophrenia: a review.

    Science.gov (United States)

    Mubarik, Ateeq; Tohid, Hassaan

    2016-01-01

    To highlight the changes in the frontal lobe of the human brain in people with schizophrenia. This was a qualitative review of the literature. Many schizophrenic patients exhibit functional, structural, and metabolic abnormalities in the frontal lobe. Some patients have few or no alterations, while some have more functional and structural changes than others. Magnetic resonance imaging (MRI) shows structural and functional changes in volume, gray matter, white matter, and functional activity in the frontal lobe, but the mechanisms underlying these changes are not yet fully understood. When schizophrenia is studied as an essential topic in the field of neuropsychiatry, neuroscientists find that the frontal lobe is the most commonly involved area of the human brain. A clear picture of how this lobe is affected in schizophrenia is still lacking. We therefore recommend that further research be conducted to improve understanding of the pathophysiology of this psychiatric dilemma.

  2. Influence of optical dome for airborne laser communication beam far-field divergence

    Science.gov (United States)

    Wang, Chao; Jiang, Lun; Tong, Shou-feng; Li, Ying-chao; Liu, Zhuang

    2017-10-01

    When the center of the dome inner and outer concentric spherical surfaces and the gimbal joint of the airborne laser communication antenna are not coincidence, the influence of asymmetry dome to communication beam far-field divergence angle for different transmitting angles is analyzed. The simulations shows that, at a maximum off-axis transmitting angle 54°, a K9 spherical dome with a 200mm diameter and 5mm thickness makes the communication beam far-field divergence angle expands to 5.27 6.46mrad from 126μrad. The divergence angle variation purely introduced by the dome manufacturing precision is very tiny, and can be ignored compared the variation introduced by the dome optical power. A lens with spherical surfaces is used to compensate the far-field divergence angle change, and after the compensation the far-field divergence angle of the beam on the whole range of transmitting angles is reduced to no more than 600μrad.

  3. Ground plane detection for autonomous robots in complex environments inclined with flexed far-field terrains

    CSIR Research Space (South Africa)

    Osunmakind, IO

    2009-11-01

    Full Text Available In this paper, collective intelligence of the Emergent Situation Awareness (ESA) technology is proposed as a supportive strategy for autonomous robotic navigation. The ability to reveal uncertainties over time on flexed far-field is a ground plane...

  4. Tsunami Source Estimate for the 1960 Chilean Earthquake from Near- and Far-Field Observations

    Science.gov (United States)

    Ho, T.; Satake, K.; Watada, S.; Fujii, Y.

    2017-12-01

    The tsunami source of the 1960 Chilean earthquake was estimated from the near- and far-field tsunami data. The 1960 Chilean earthquake is known as the greatest earthquake instrumentally ever recorded. This earthquake caused a large tsunami which was recorded by 13 near-field tidal gauges in South America, and 84 far-field stations around the Pacific Ocean at the coasts of North America, Asia, and Oceania. The near-field stations had been used for estimating the tsunami source [Fujii and Satake, Pageoph, 2013]. However, far-field tsunami waveforms have not been utilized because of the discrepancy between observed and simulated waveforms. The observed waveforms at the far-field stations are found systematically arrived later than the simulated waveforms. This phenomenon has been also observed in the tsunami of the 2004 Sumatra earthquake, the 2010 Chilean earthquake, and the 2011 Tohoku earthquake. Recently, the factors for the travel time delay have been explained [Watada et al., JGR, 2014; Allgeyer and Cummins, GRL, 2014], so the far-field data are usable for tsunami source estimation. The phase correction method [Watada et al., JGR, 2014] converts the tsunami waveforms computed by the linear long wave into the dispersive waveform which accounts for the effects of elasticity of the Earth and ocean, ocean density stratification, and gravitational potential change associated with tsunami propagation. We apply the method to correct the computed waveforms. For the preliminary initial sea surface height inversion, we use 12 near-field stations and 63 far-field stations, located in the South and North America, islands in the Pacific Ocean, and the Oceania. The estimated tsunami source from near-field stations is compared with the result from both near- and far-field stations. Two estimated sources show a similar pattern: a large sea surface displacement concentrated at the south of the epicenter close to the coast and extended to south. However, the source estimated from

  5. Emphysema lung lobe volume reduction: effects on the ipsilateral and contralateral lobes

    Energy Technology Data Exchange (ETDEWEB)

    Brown, Matthew S.; Kim, Hyun J.; Abtin, Fereidoun G.; Galperin-Aizenberg, Maya; Pais, Richard; Da Costa, Irene G.; Ordookhani, Arash; Chong, Daniel; Ni, Chiayi; McNitt-Gray, Michael F.; Goldin, Jonathan G. [David Geffen School of Medicine at UCLA, Center for Computer Vision and Imaging Biomarkers, Department of Radiological Sciences, Los Angeles, CA (United States); Strange, Charlie [Medical University of South Carolina, Department of Pulmonary and Critical Care Medicine, Columbia, SC (United States); Tashkin, Donald P. [David Geffen School of Medicine at UCLA, Division of Pulmonary and Critical Care Medicine, Los Angeles, CA (United States)

    2012-07-15

    To investigate volumetric and density changes in the ipsilateral and contralateral lobes following volume reduction of an emphysematous target lobe. The study included 289 subjects with heterogeneous emphysema, who underwent bronchoscopic volume reduction of the most diseased lobe with endobronchial valves and 132 untreated controls. Lobar volume and low-attenuation relative area (RA) changes post-procedure were measured from computed tomography images. Regression analysis (Spearman's rho) was performed to test the association between change in the target lobe volume and changes in volume and density variables in the other lobes. The target lobe volume at full inspiration in the treatment group had a mean reduction of -0.45 L (SE = 0.034, P < 0.0001), and was associated with volume increases in the ipsilateral lobe (rho = -0.68, P < 0.0001) and contralateral lung (rho = -0.16, P = 0.006), and overall reductions in expiratory RA (rho = 0.31, P < 0.0001) and residual volume (RV)/total lung capacity (TLC) (rho = 0.13, P = 0.03). When the volume of an emphysematous target lobe is reduced, the volume is redistributed primarily to the ipsilateral lobe, with an overall reduction. Image-based changes in lobar volumes and densities indicate that target lobe volume reduction is associated with statistically significant overall reductions in air trapping, consistent with expansion of the healthier lung. (orig.)

  6. Emphysema lung lobe volume reduction: effects on the ipsilateral and contralateral lobes

    International Nuclear Information System (INIS)

    Brown, Matthew S.; Kim, Hyun J.; Abtin, Fereidoun G.; Galperin-Aizenberg, Maya; Pais, Richard; Da Costa, Irene G.; Ordookhani, Arash; Chong, Daniel; Ni, Chiayi; McNitt-Gray, Michael F.; Goldin, Jonathan G.; Strange, Charlie; Tashkin, Donald P.

    2012-01-01

    To investigate volumetric and density changes in the ipsilateral and contralateral lobes following volume reduction of an emphysematous target lobe. The study included 289 subjects with heterogeneous emphysema, who underwent bronchoscopic volume reduction of the most diseased lobe with endobronchial valves and 132 untreated controls. Lobar volume and low-attenuation relative area (RA) changes post-procedure were measured from computed tomography images. Regression analysis (Spearman's rho) was performed to test the association between change in the target lobe volume and changes in volume and density variables in the other lobes. The target lobe volume at full inspiration in the treatment group had a mean reduction of -0.45 L (SE = 0.034, P < 0.0001), and was associated with volume increases in the ipsilateral lobe (rho = -0.68, P < 0.0001) and contralateral lung (rho = -0.16, P = 0.006), and overall reductions in expiratory RA (rho = 0.31, P < 0.0001) and residual volume (RV)/total lung capacity (TLC) (rho = 0.13, P = 0.03). When the volume of an emphysematous target lobe is reduced, the volume is redistributed primarily to the ipsilateral lobe, with an overall reduction. Image-based changes in lobar volumes and densities indicate that target lobe volume reduction is associated with statistically significant overall reductions in air trapping, consistent with expansion of the healthier lung. (orig.)

  7. Representation of thermal information in the antennal lobe of leaf-cutting ants

    Directory of Open Access Journals (Sweden)

    Markus eRuchty

    2010-11-01

    Full Text Available Insects are equipped with various types of antennal sensilla, which house thermosensitive neurons adapted to receive different parameters of the thermal environment for a variety of temperature-guided behaviors. In the leaf-cutting ant Atta vollenweideri, the physiology and the morphology of the thermosensitive sensillum coeloconicum (Sc has been thoroughly investigated. However, the central projections of its receptor neurons are unknown. Here we selectively stained the three neurons found in single Sc and tracked their axons into the brain of Atta vollenweideri workers. Each of the three axons terminates in a single glomerulus of the antennal lobe (Sc-glomeruli. Two of the innervated glomeruli are adjacent to each other and are located laterally, while the third one is clearly separated and located medially in the antennal lobe. Using two-photon Ca2+ imaging of antennal lobe projection neurons, we studied where in the antennal lobe thermal information is represented. In the 11 investigated antennal lobes, we found up to 10 different glomeruli in a single specimen responding to temperature stimulation. Both, warm- and cold-sensitive glomeruli could be identified. The thermosensitive glomeruli were mainly located in the medial part of the antennal lobe. Based on the general representation of thermal information in the antennal lobe and functional data on the Sc-glomeruli we conclude that temperature stimuli received by Sc are processed in the medial of the three target glomeruli. The present study reveals an important role of the antennal lobe in temperature processing and links a specific thermosensitive neuron to its central target glomerulus.

  8. Human Frontal Lobes and AI Planning Systems

    Science.gov (United States)

    Levinson, Richard; Lum, Henry Jr. (Technical Monitor)

    1994-01-01

    Human frontal lobes are essential for maintaining a self-regulating balance between predictive and reactive behavior. This paper describes a system that integrates prediction and reaction based on neuropsychological theories of frontal lobe function. In addition to enhancing our understanding of deliberate action in humans' the model is being used to develop and evaluate the same properties in machines. First, the paper presents some background neuropsychology in order to set a general context. The role of frontal lobes is then presented by summarizing three theories which formed the basis for this work. The components of an artificial frontal lobe are then discussed from both neuropsychological and AI perspectives. The paper concludes by discussing issues and methods for evaluating systems that integrate planning and reaction.

  9. Deployment Instabilities of Lobed-Pumpkin Balloon

    Science.gov (United States)

    Nakashino, Kyoichi

    A lobed-pumpkin balloon, currently being developed in ISAS/JAXA as well as in NASA, is a promising vehicle for long duration scientific observations in the stratosphere. Recent ground and flight experiments, however, have revealed that the balloon has deployment instabilities under certain conditions. In order to overcome the instability problems, a next generation SPB called 'tawara' type balloon has been proposed, in which an additional cylindrical part is appended to the standard lobed-pumpkin balloon. The present study investigates the deployment stability of tawara type SPB in comparison to that of standard lobed-pumpkin SPB through eigenvalue analysis on the basis of finite element methods. Our numerical results show that tawara type SPB enjoys excellent deployment performance over the standard lobed-pumpkin SPBs.

  10. Redefining Lumpectomy Using a Modification of the Sick Lobe Hypothesis and Ductal Anatomy

    International Nuclear Information System (INIS)

    Dooley, W.; Bong, J.; Parker, J

    2011-01-01

    Objectives. The Sick Lobe hypothesis states that breast cancers evolve from entire lobes or portions of lobes of the breast where initiation events have occurred early in development. The implication is that some cancers are isolated events and others are truly multi-focal but limited to single lobar-ductal units. Methods. This is a single surgeon retrospective review of early stage breast cancer lumpectomy patients treated from 1/2000 to 2/2005. Ductal endoscopy was used direct lumpectomy surgical margins by defining ductal anatomy and mapping proliferative changes within the sick lobe for complete excision. Results. Breast conservation surgery for stage 02 breast cancer with an attempt to perform endoscopy in association with therapeutic lumpectomy was performed in 554 patients (successful endoscopy in 465 cases). With an average followup of >5 years for the entire group, annual hazard rate for local failure in traditional lumpectomy without ductal mapping was 0.97%/yr. and for lumpectomy with ductal mapping and excision of entire sick lobe was 0.18%/yr. With endoscopy, 42% of patients were found to have extensive disease within their sick lobe. Conclusions. Targeting breast cancer lumpectomy using endoscopy and excision of regional associated proliferation seems associated with lower recurrence in this non-randomized series

  11. Side lobe suppression in phase mask-based nonlinear superresolution microscopy

    Science.gov (United States)

    Beams, Ryan; Stranick, Stephan J.

    2017-08-01

    We compare side lobe suppression methods for nonlinear superresolution optical microscopy using phase masked excitation beams. The excitation point spread function (PSF) can be engineered by introducing a phase mask for superresolution microscopy. By applying a single π phase step to the excitation the central spot can be narrowed and provide improved lateral resolution. However, the energy redistribution leads to side lobes with increased intensity that complicates imaging applications. Several methods have been implemented to suppress the strength of the side lobes including confocal detection and utilizing beams with different phase masks in multiphoton microscopy. Side lobe suppression methods using confocal detection and different phase masks for the excitation beams are compared theoretically and experimentally. These results demonstrate the additional flexibility for PSF engineering for nonlinear optical processes.

  12. Plasmonic and Mie scattering control of far-field interference for regular ripple formation on various material substrates.

    Science.gov (United States)

    Obara, Go; Maeda, Naoki; Miyanishi, Tomoya; Terakawa, Mitsuhiro; Nedyalkov, Nikolay N; Obara, Minoru

    2011-09-26

    We present experimental and theoretical results on plasmonic control of far-field interference for regular ripple formation on semiconductor and metal. Experimental observation of interference ripple pattern on Si substrate originating from the gold nanosphere irradiated by femtosecond laser is presented. Gold nanosphere is found to be an origin for ripple formation. Arbitrary intensity ripple patterns are theoretically controllable by depositing desired plasmonic and Mie scattering far-field pattern generators. The plasmonic far-field generation is demonstrated not only by metallic nanostructures but also by the controlled surface structures such as ridge and trench structures on various material substrates. © 2011 Optical Society of America

  13. Lung lobe torsion in seven juvenile dogs.

    Science.gov (United States)

    Latimer, Christian R; Lux, Cassie N; Sutton, Jessie S; Culp, William T N

    2017-12-15

    CASE DESCRIPTION 7 juvenile (< 12 months old) dogs with lung lobe torsion were evaluated. CLINICAL FINDINGS All patients were male; breeds included Pug (n = 5), Chinese Shar-Pei (1), and Bullmastiff (1). Dyspnea and lethargy were the most common initial complaints, with a duration of clinical signs ranging from 1 to 10 days. A CBC showed leukocytosis and neutrophilia in all dogs. Anemia was present in 6 dogs, 2 of which received packed RBC transfusions. The diagnosis was made on the basis of results of thoracic radiography, CT, ultrasonography, or a combination of modalities. The left cranial lung lobe was most commonly affected (n = 4), followed by the right middle lung lobe (2) and the right cranial lung lobe (1). TREATMENT AND OUTCOME A lateral intercostal thoracotomy with lobectomy of the affected lobe was performed in all patients. All dogs survived to be discharged between 1 and 2 days postoperatively. Six of 7 owners contacted for follow-up information 7 to 170 months after discharge reported satisfaction with the treatment and no apparent signs of recurrence of disease. CLINICAL RELEVANCE The juvenile patients of this report were successfully treated surgically with no apparent complications. Clinicians should be aware of the possibility of lung lobe torsion when evaluating young dogs with clinical signs related to the respiratory system, including those with vague signs, to avoid undue delays in treatment.

  14. Frontal lobe connectivity and cognitive impairment in pediatric frontal lobe epilepsy.

    Science.gov (United States)

    Braakman, Hilde M H; Vaessen, Maarten J; Jansen, Jacobus F A; Debeij-van Hall, Mariette H J A; de Louw, Anton; Hofman, Paul A M; Vles, Johan S H; Aldenkamp, Albert P; Backes, Walter H

    2013-03-01

    Cognitive impairment is frequent in children with frontal lobe epilepsy (FLE), but its etiology is unknown. With functional magnetic resonance imaging (fMRI), we have explored the relationship between brain activation, functional connectivity, and cognitive functioning in a cohort of pediatric patients with FLE and healthy controls. Thirty-two children aged 8-13 years with FLE of unknown cause and 41 healthy age-matched controls underwent neuropsychological assessment and structural and functional brain MRI. We investigated to which extent brain regions activated in response to a working memory task and assessed functional connectivity between distant brain regions. Data of patients were compared to controls, and patients were grouped as cognitively impaired or unimpaired. Children with FLE showed a global decrease in functional brain connectivity compared to healthy controls, whereas brain activation patterns in children with FLE remained relatively intact. Children with FLE complicated by cognitive impairment typically showed a decrease in frontal lobe connectivity. This decreased frontal lobe connectivity comprised both connections within the frontal lobe as well as connections from the frontal lobe to the parietal lobe, temporal lobe, cerebellum, and basal ganglia. Decreased functional frontal lobe connectivity is associated with cognitive impairment in pediatric FLE. The importance of impairment of functional integrity within the frontal lobe network, as well as its connections to distant areas, provides new insights in the etiology of the broad-range cognitive impairments in children with FLE. Wiley Periodicals, Inc. © 2012 International League Against Epilepsy.

  15. A Compact RFID Reader Antenna for UHF Near-Field and Far-Field Operations

    Directory of Open Access Journals (Sweden)

    Lai Xiao zheng

    2013-01-01

    Full Text Available A compact loop antenna is presented for mobile ultrahigh frequency (UHF radio frequency identification (RFID application. This antenna, printed on a 0.8 mm thick FR4 substrate with a small size of 31 mm × 31 mm, achieves good impedance bandwidth from 897 to 928 MHz, which covers USA RFID Band (902–928 MHz. The proposed loop configuration, with a split-ring resonator (SRR coupled inside it, demonstrates strong and uniform magnetic field distribution in the near-field antenna region. Its linearly polarized radiation pattern provides available far-field gain. Finally, the reading capabilities of antenna are up to 56 mm for near-field and 1.05 m for far-field UHF RFID operations, respectively.

  16. Far-field analysis of axially symmetric three-dimensional directional cloaks.

    Science.gov (United States)

    Ciracì, Cristian; Urzhumov, Yaroslav; Smith, David R

    2013-04-22

    Axisymmetric radiating and scattering structures whose rotational invariance is broken by non-axisymmetric excitations present an important class of problems in electromagnetics. For such problems, a cylindrical wave decomposition formalism can be used to efficiently obtain numerical solutions to the full-wave frequency-domain problem. Often, the far-field, or Fraunhofer region is of particular interest in scattering cross-section and radiation pattern calculations; yet, it is usually impractical to compute full-wave solutions for this region. Here, we propose a generalization of the Stratton-Chu far-field integral adapted for 2.5D formalism. The integration over a closed, axially symmetric surface is analytically reduced to a line integral on a meridional plane. We benchmark this computational technique by comparing it with analytical Mie solutions for a plasmonic nanoparticle, and apply it to the design of a three-dimensional polarization-insensitive cloak.

  17. Femtosecond refractive-index tailoring of an optical fiber and phase retrieval from far-field measurements

    DEFF Research Database (Denmark)

    Savolainen, Juha-Matti; Grüner-Nielsen, Lars; Kristensen, Poul

    2013-01-01

    A refractive-index change is written inside an optical fiber close to the end face by femtosecond laser light. The induced phase change is measured by analyzing the far-field intensity profiles before and after the irradiation.......A refractive-index change is written inside an optical fiber close to the end face by femtosecond laser light. The induced phase change is measured by analyzing the far-field intensity profiles before and after the irradiation....

  18. The medial temporal lobe: memory and beyond.

    Science.gov (United States)

    Lech, Robert K; Suchan, Boris

    2013-10-01

    The structures of the medial temporal lobe, e.g., the hippocampus, entorhinal cortex, perirhinal cortex, and parahippocampal cortex, are known to be essential for long-term memory processing and hence are labeled the medial temporal lobe memory system. Nevertheless, the exact contributions of each structure and the involvement in different cognitive processes remain controversial. This article discusses recent findings dealing with recognition memory and a long lasting involvement of the hippocampus and perirhinal cortex in episodic memory, based on functional imaging and lesion studies. Furthermore, a new paradigm employing objective manipulations of recollection and familiarity is presented, showing no anatomical distinction for these two processes, as opposed to studies using subjective ratings. Additionally, results regarding an involvement of the medial temporal lobe in visual processing are presented, in general supporting the visual-mnemonic theory. The discussed findings show that many questions regarding the functional organization remain unsolved, and that we are in need of further research to create a comprehensive model of the medial temporal lobe. For this, we might need to give up the distinctions into different cognitive processes and start to investigate the different types of representations that are processed by the medial temporal lobe. Copyright © 2013 Elsevier B.V. All rights reserved.

  19. Development of a dynamic model for the lung lobes and airway tree in the NCAT phantom

    Science.gov (United States)

    Garrity, J. M.; Segars, W. P.; Knisley, S. B.; Tsui, B. M. W.

    2003-06-01

    The four-dimensional (4-D) NCAT phantom was developed to realistically model human anatomy based on the visible human data and cardiac and respiratory motions based on 4-D tagged magnetic resonance imaging and respiratory-gated CT data from normal human subjects. Currently, the 4-D NCAT phantom does not include the airway tree or its motion within the lungs. Also, each lung is defined with a single surface; the individual lobes are not distinguished. The authors further the development of the phantom by creating dynamic models for the individual lung lobes and for the airway tree in each lobe. NURBS surfaces for the lobes and an initial airway tree model (/spl sim/ 4 generations) were created through manual segmentation of the visible human data. A mathematical algorithm with physiological constraints was used to extend the original airway model to fill each lobe. For each parent airway branch inside a lobe, the algorithm extends the airway tree by creating two daughter branches modeled with cylindrical tubes. Parameters for the cylindrical tubes such as diameter, length, and angle are constrained based on flow parameters and available lung space.

  20. Infectious Causes of Right Middle Lobe Syndrome.

    Science.gov (United States)

    Rashid, Aatif; Nanjappa, Sowmya; Greene, John N

    2017-01-01

    Right middle lobe (RML) syndrome is defined as recurrent or chronic obstruction or infection of the middle lobe of the right lung. Nonobstructive causes of middle lobe syndrome include inflammatory processes and defects in the bronchial anatomy and collateral ventilation. We report on 2 case patients with RML syndrome, one due to infection with Mycobacterium avium complex followed by M asiaticum infection and the other due to allergic bronchopulmonary aspergillosis. A history of atopy, asthma, or chronic obstructive pulmonary disease has been reported in up to one-half of those with RML. The diagnosis can be made by plain radiography, computed tomography, and bronchoscopy. Medical treatment consists of bronchodilators, mucolytics, and antimicrobials. Patients whose disease is unresponsive to treatment and those with obstructive RML syndrome can be offered surgical treatment.

  1. Far-field Lorenz-Mie scattering in an absorbing host medium: Theoretical formalism and FORTRAN program

    Science.gov (United States)

    Mishchenko, Michael I.; Yang, Ping

    2018-01-01

    In this paper we make practical use of the recently developed first-principles approach to electromagnetic scattering by particles immersed in an unbounded absorbing host medium. Specifically, we introduce an actual computational tool for the calculation of pertinent far-field optical observables in the context of the classical Lorenz-Mie theory. The paper summarizes the relevant theoretical formalism, explains various aspects of the corresponding numerical algorithm, specifies the input and output parameters of a FORTRAN program available at https://www.giss.nasa.gov/staff/mmishchenko/Lorenz-Mie.html, and tabulates benchmark results useful for testing purposes. This public-domain FORTRAN program enables one to solve the following two important problems: (i) simulate theoretically the reading of a remote well-collimated radiometer measuring electromagnetic scattering by an individual spherical particle or a small random group of spherical particles; and (ii) compute the single-scattering parameters that enter the vector radiative transfer equation derived directly from the Maxwell equations.

  2. Automated MRI parcellation of the frontal lobe.

    Science.gov (United States)

    Ranta, Marin E; Chen, Min; Crocetti, Deana; Prince, Jerry L; Subramaniam, Krish; Fischl, Bruce; Kaufmann, Walter E; Mostofsky, Stewart H

    2014-05-01

    Examination of associations between specific disorders and physical properties of functionally relevant frontal lobe sub-regions is a fundamental goal in neuropsychiatry. Here, we present and evaluate automated methods of frontal lobe parcellation with the programs FreeSurfer(FS) and TOADS-CRUISE(T-C), based on the manual method described in Ranta et al. [2009]: Psychiatry Res 172:147-154 in which sulcal-gyral landmarks were used to manually delimit functionally relevant regions within the frontal lobe: i.e., primary motor cortex, anterior cingulate, deep white matter, premotor cortex regions (supplementary motor complex, frontal eye field, and lateral premotor cortex) and prefrontal cortex (PFC) regions (medial PFC, dorsolateral PFC, inferior PFC, lateral orbitofrontal cortex [OFC] and medial OFC). Dice's coefficient, a measure of overlap, and percent volume difference were used to measure the reliability between manual and automated delineations for each frontal lobe region. For FS, mean Dice's coefficient for all regions was 0.75 and percent volume difference was 21.2%. For T-C the mean Dice's coefficient was 0.77 and the mean percent volume difference for all regions was 20.2%. These results, along with a high degree of agreement between the two automated methods (mean Dice's coefficient = 0.81, percent volume difference = 12.4%) and a proof-of-principle group difference analysis that highlights the consistency and sensitivity of the automated methods, indicate that the automated methods are valid techniques for parcellation of the frontal lobe into functionally relevant sub-regions. Thus, the methodology has the potential to increase efficiency, statistical power and reproducibility for population analyses of neuropsychiatric disorders with hypothesized frontal lobe contributions. Copyright © 2013 Wiley Periodicals, Inc.

  3. Temporal lobe sclerosis associated with hippocampal sclerosis in temporal lobe epilepsy: neuropathological features.

    Science.gov (United States)

    Thom, Maria; Eriksson, Sofia; Martinian, Lillian; Caboclo, Luis O; McEvoy, Andrew W; Duncan, John S; Sisodiya, Sanjay M

    2009-08-01

    Widespread changes involving neocortical and mesial temporal lobe structures can be present in patients with temporal lobe epilepsy and hippocampal sclerosis. The incidence, pathology, and clinical significance of neocortical temporal lobe sclerosis (TLS) are not well characterized. We identified TLS in 30 of 272 surgically treated cases of hippocampal sclerosis. Temporal lobe sclerosis was defined by variable reduction of neurons from cortical layers II/III and laminar gliosis; it was typically accompanied by additional architectural abnormalities of layer II, that is, abnormal neuronal orientation and aggregation. Quantitative analysis including tessellation methods for the distribution of layer II neurons supported these observations. In 40% of cases, there was a gradient of TLS with more severe involvement toward the temporal pole, possibly signifying involvement of hippocampal projection pathways. There was a history of a febrile seizure as an initial precipitating injury in 73% of patients with TLS compared with 36% without TLS; no other clinical differences between TLS and non-TLS cases were identified. Temporal lobe sclerosis was not evident preoperatively by neuroimaging. No obvious effect of TLS on seizure outcome was noted after temporal lobe resection; 73% became seizure-free at 2-year follow-up. In conclusion, approximately 11% of surgically treated hippocampal sclerosis is accompanied by TLS. Temporal lobe sclerosis is likely an acquired process with accompanying reorganizational dysplasia and an extension of mesial temporal sclerosis rather than a separate pathological entity.

  4. Formation of Bipolar Lobes by Jets

    Science.gov (United States)

    Soker, Noam

    2002-04-01

    I conduct an analytical study of the interaction of jets, or a collimated fast wind (CFW), with a previously blown asymptotic giant branch (AGB) slow wind. Such jets (or CFWs) are supposedly formed when a compact companion, a main-sequence star, or a white dwarf accretes mass from the AGB star, forms an accretion disk, and blows two jets. This type of flow, which I think shapes bipolar planetary nebulae (PNs), requires three-dimensional gasdynamical simulations, which are limited in the parameter space they can cover. By imposing several simplifying assumptions, I derive simple expressions which reproduce some basic properties of lobes in bipolar PNs and which can be used to guide future numerical simulations. I quantitatively apply the results to two proto-PNs. I show that the jet interaction with the slow wind can form lobes which are narrow close to, and far away from, the central binary system, and which are wider somewhere in between. Jets that are recollimated and have constant cross section can form cylindrical lobes with constant diameter, as observed in several bipolar PNs. Close to their source, jets blown by main-sequence companions are radiative; only further out they become adiabatic, i.e., they form high-temperature, low-density bubbles that inflate the lobes.

  5. Centrifugal acceleration in the magnetotail lobes

    Directory of Open Access Journals (Sweden)

    H. Nilsson

    2010-02-01

    Full Text Available Combined Cluster EFW and EDI measurements have shown that cold ion outflow in the magnetospheric lobes dominates the hydrogen ion outflow from the Earth's atmosphere. The ions have too low kinetic energy to be measurable with particle instruments, at least for the typical spacecraft potential of a sunlit spacecraft in the tenuous lobe plasmas outside a few RE. The measurement technique yields both density and bulk velocity, which can be combined with magnetic field measurements to estimate the centrifugal acceleration experienced by these particles. We present a quantitative estimate of the centrifugal acceleration, and the velocity change with distance which we would expect due to centrifugal acceleration. It is found that the centrifugal acceleration is on average outward with an average value of about of 5 m s−2. This is small, but acting during long transport times and over long distances the cumulative effect is significant, while still consistent with the relatively low velocities estimated using the combination of EFW and EDI data. The centrifugal acceleration should accelerate any oxygen ions in the lobes to energies observable by particle spectrometers. The data set also put constraints on the effectiveness of any other acceleration mechanisms acting in the lobes, where the total velocity increase between 5 and 19 RE geocentric distance is less than 5 km s−1.

  6. Controlling activation site density by low-energy far-field stimulation in cardiac tissue

    Science.gov (United States)

    Hörning, Marcel; Takagi, Seiji; Yoshikawa, Kenichi

    2012-06-01

    Tachycardia and fibrillation are potentially fatal arrhythmias associated with the formation of rotating spiral waves in the heart. Presently, the termination of these types of arrhythmia is achieved by use of antitachycardia pacing or cardioversion. However, these techniques have serious drawbacks, in that they either have limited application or produce undesirable side effects. Low-energy far-field stimulation has recently been proposed as a superior therapy. This proposed therapeutic method would exploit the phenomenon in which the application of low-energy far-field shocks induces a large number of activation sites (“virtual electrodes”) in tissue. It has been found that the formation of such sites can lead to the termination of undesired states in the heart and the restoration of normal beating. In this study we investigate a particular aspect of this method. Here we seek to determine how the activation site density depends on the applied electric field through in vitro experiments carried out on neonatal rat cardiac tissue cultures. The results indicate that the activation site density increases exponentially as a function of the intracellular conductivity and the level of cell isotropy. Additionally, we report numerical results obtained from bidomain simulations of the Beeler-Reuter model that are quantitatively consistent with our experimental results. Also, we derive an intuitive analytical framework that describes the activation site density and provides useful information for determining the ratio of longitudinal to transverse conductivity in a cardiac tissue culture. The results obtained here should be useful in the development of an actual therapeutic method based on low-energy far-field pacing. In addition, they provide a deeper understanding of the intrinsic properties of cardiac cells.

  7. Eccentrically-Layered Active Coated Nano-Particles for Directive Near- and Far-Field Radiation

    Directory of Open Access Journals (Sweden)

    Rasmus Ø. Thorsen

    2015-06-01

    Full Text Available The present work shows how the eccentricity in active nano-particles may lead to very interesting and rather directive near- and far-field radiation patterns. The nano-particle is of a three-layer type and consists of a silica core, a free-space middle layer and an outer silver shell and is excited by a magnetic line source. The constant frequency gain model is included in the silica core, and the eccentricity is introduced through appropriate displacements of the core. It is shown that the eccentricity in a nano-particle, which was initially designed to excite a strong dipole mode, causes a progressively larger excitation of several other (including higher order modes, this being more so the larger the core displacement. Specifically, eccentric nano-particles are identified with comparable simultaneous excitations of dipole and quadrupole modes, with associated large values of the radiated power and, even more notably, enhanced and directive near- and far-field radiation patterns. The main beam of these patterns is shown to be effectively tailored (enhanced, reshaped and steered by the direction and amount of the core displacement. The eccentric nano-particles can be additionally gain optimized to boost their near-field response and the radiated power, while retaining the directivity of the gain unoptimized eccentric cases. Owing to their very directive nearand far-field patterns, the proposed eccentric, active three-layer nano-particles may provide alternative strategies towards the design of directive nano-antennas relative to several of the existing solutions.

  8. Radiologic evaluation of right middle lobe collapse

    International Nuclear Information System (INIS)

    Kwun, Dae Young; Kim, Jong Deok; Kim, Jong Chul

    1989-01-01

    There are many pathogenetic factors for collapse of right middle lobe; profuse peribronchial clustering of lymph nodes about the right middle lobe bronchus, poor drainage of the bronchus because of its acute angle of take-off from the intermediate bronchus, and the isolation of this small lobe from the right upper and lower lobes, and thus from the aerating effects of collateral ventilation. Retrospectively we reviewed 36 cases of right of right middle lobe collapse of which causes were confirmed by histopathologic or bronchographic findings during the recent 6 years from March 1983 to February 1988 at Inje College Pusan Paik Hospital, and obtained the following results: 1. Male to female ratio was 1:1:4,and peak incidence (64%) was in the fifth and sixth decades with the mean age of 51.1 years. 2. Bronchiectasis was the most common cause (30.6%), and the others were chronic bronchitis (25.0%), pulmonary tuberculosis (19.4%), lung cancer (16.7%), and non-specific inflammatory disease (8.3%). This suggests benign disease is 5 times more common cause of right middle lobe collapse than lung cancer. 3. Among the plain chest radiolograph findings, obliteration of right cardiac border and triangular radiopaque density were the most frequent findings(77.8% in each) and the next was downward and anterior displacement of minor and major fissures (55.6%) 4. Bronchography was done in 11 cases; bronchiectasis was found in 8 cases and chronic bronchitis in 3 cases. Right middle lobe bronchus was obstructed in 2 cases of chronic bronchitis. 5. Chest CT scan was performed in 4 cases of lung cancer, 2 of non-specific inflammatory disease, and 1 of pulmonary tuberculosis: all of lung cancer revealed hilar mass, budged or lobulated fissures, in homogenous density, and mediastinal lymph node enlargement, and all benign disease showed homogenous density and flat to concave fissures. Right middle lobar bronchus narrowing was seen in 5 cases and its obstruction in 2 cases

  9. Multipass laser amplification with near-field far-field optical separation

    Science.gov (United States)

    Hagen, Wilhelm F.

    1979-01-01

    This invention discloses two classes of optical configurations for high power laser amplification, one allowing near-field and the other allowing far-field optical separation, for the multiple passage of laser pulses through one or more amplifiers over an open optical path. These configurations may reimage the amplifier or any other part of the cavity on itself so as to suppress laser beam intensity ripples that arise from diffraction and/or non-linear effects. The optical cavities combine the features of multiple passes, spatial filtering and optical reimaging and allow sufficient time for laser gain recovery.

  10. Judicious distribution of laser emitters to shape the desired far-field patterns

    Science.gov (United States)

    Valagiannopoulos, Constantinos A.; Kovanis, Vassilios

    2017-06-01

    The far-field pattern of a simple one-dimensional laser array of emitters radiating into free space is considered. In the course of investigating the inverse problem for their near fields leading to a target beam form, surprisingly, we found that the result is successful when the matrix of the corresponding linear system is not well scaled. The essence of our numerical observations is captured by an elegant inequality defining the functional range of the optical distance between two neighboring emitters. Our finding can restrict substantially the parametric space of integrated photonic systems and simplify significantly the subsequent optimizations.

  11. Near-field to far-field characterization of speckle patterns generated by disordered nanomaterials.

    Science.gov (United States)

    Parigi, Valentina; Perros, Elodie; Binard, Guillaume; Bourdillon, Céline; Maître, Agnès; Carminati, Rémi; Krachmalnicoff, Valentina; De Wilde, Yannick

    2016-04-04

    We study the intensity spatial correlation function of optical speckle patterns above a disordered dielectric medium in the multiple scattering regime. The intensity distributions are recorded by scanning near-field optical microscopy (SNOM) with sub-wavelength spatial resolution at variable distances from the surface in a range which spans continuously from the near-field (distance ≪ λ) to the far-field regime (distance ≫ λ). The non-universal behavior at sub-wavelength distances reveals the connection between the near-field speckle pattern and the internal structure of the medium.

  12. On the Concept of Random Orientation in Far-Field Electromagnetic Scattering by Nonspherical Particles

    Science.gov (United States)

    Mishchenko, Michael I.; Yurkin, Maxim A.

    2017-01-01

    Although the model of randomly oriented nonspherical particles has been used in a great variety of applications of far-field electromagnetic scattering, it has never been defined in strict mathematical terms. In this Letter we use the formalism of Euler rigid-body rotations to clarify the concept of statistically random particle orientations and derive its immediate corollaries in the form of most general mathematical properties of the orientation-averaged extinction and scattering matrices. Our results serve to provide a rigorous mathematical foundation for numerous publications in which the notion of randomly oriented particles and its light-scattering implications have been considered intuitively obvious.

  13. Near- to far-field imaging of phase evolution of light emanating from a metal nanoslit.

    Science.gov (United States)

    Jung, Yun Suk; Xi, Yonggang; Wuenschell, Jeff; Kim, Hong Koo

    2008-11-10

    We report near- to far-field measurement of optical wavefronts emanating from a nanoslit formed in a thin (50 nm thick) Ag film. The evolution of optical phases is imaged using a self-interference technique in conjunction with a scanning probe method. The phase relationship of the slit-transmitted waves with respect to the direct transmission through the thin metal film is quantitatively established. The singular-phase points resulting from the interplay of slit diffraction and surface plasmons are identified in the intermediate-field region.

  14. Proton magnetic resonance spectroscopy of temporal lobe white matter in patients with histologically proven hippocampal sclerosis

    NARCIS (Netherlands)

    Meiners, LC; van der Grond, J; van Rijen, PC; Springorum, R; de Kort, GAP; Jansen, GH

    The purpose of this study was to assess temporal lobe white matter changes accompanying hippocampal sclerosis on magnetic resonance (MR) imaging using single-voxel H-1 MR spectroscopy and to strengthen the hypothesis that these white matter changes are caused by myelin alterations. In 11 patients

  15. Genetics Home Reference: autosomal dominant nocturnal frontal lobe epilepsy

    Science.gov (United States)

    ... Health Conditions ADNFLE Autosomal dominant nocturnal frontal lobe epilepsy Printable PDF Open All Close All Enable Javascript ... collapse boxes. Description Autosomal dominant nocturnal frontal lobe epilepsy ( ADNFLE ) is an uncommon form of epilepsy that ...

  16. Leukocyte nucleus segmentation and nucleus lobe counting.

    Science.gov (United States)

    Chan, Yung-Kuan; Tsai, Meng-Hsiun; Huang, Der-Chen; Zheng, Zong-Han; Hung, Kun-Ding

    2010-11-12

    Leukocytes play an important role in the human immune system. The family of leukocytes is comprised of lymphocytes, monocytes, eosinophils, basophils, and neutrophils. Any infection or acute stress may increase or decrease the number of leukocytes. An increased percentage of neutrophils may be caused by an acute infection, while an increased percentage of lymphocytes can be caused by a chronic bacterial infection. It is important to realize an abnormal variation in the leukocytes. The five types of leukocytes can be distinguished by their cytoplasmic granules, staining properties of the granules, size of cell, the proportion of the nuclear to the cytoplasmic material, and the type of nucleolar lobes. The number of lobes increased when leukemia, chronic nephritis, liver disease, cancer, sepsis, and vitamin B12 or folate deficiency occurred. Clinical neutrophil hypersegmentation has been widely used as an indicator of B12 or folate deficiency.Biomedical technologists can currently recognize abnormal leukocytes using human eyes. However, the quality and efficiency of diagnosis may be compromised due to the limitations of the biomedical technologists' eyesight, strength, and medical knowledge. Therefore, the development of an automatic leukocyte recognition system is feasible and necessary. It is essential to extract the leukocyte region from a blood smear image in order to develop an automatic leukocyte recognition system. The number of lobes increased when leukemia, chronic nephritis, liver disease, cancer, sepsis, and vitamin B12 or folate deficiency occurred. Clinical neutrophil hypersegmentation has been widely used as an indicator of B12 or folate deficiency. The purpose of this paper is to contribute an automatic leukocyte nuclei image segmentation method for such recognition technology. The other goal of this paper is to develop the method of counting the number of lobes in a cell nucleus. The experimental results demonstrated impressive segmentation accuracy

  17. Metal/Polymer Based Stretchable Antenna for Constant Frequency Far-Field Communication in Wearable Electronics

    KAUST Repository

    Hussain, Aftab M.

    2015-10-06

    Body integrated wearable electronics can be used for advanced health monitoring, security, and wellness. Due to the complex, asymmetric surface of human body and atypical motion such as stretching in elbow, finger joints, wrist, knee, ankle, etc. electronics integrated to body need to be physically flexible, conforming, and stretchable. In that context, state-of-the-art electronics are unusable due to their bulky, rigid, and brittle framework. Therefore, it is critical to develop stretchable electronics which can physically stretch to absorb the strain associated with body movements. While research in stretchable electronics has started to gain momentum, a stretchable antenna which can perform far-field communications and can operate at constant frequency, such that physical shape modulation will not compromise its functionality, is yet to be realized. Here, a stretchable antenna is shown, using a low-cost metal (copper) on flexible polymeric platform, which functions at constant frequency of 2.45 GHz, for far-field applications. While mounted on a stretchable fabric worn by a human subject, the fabricated antenna communicated at a distance of 80 m with 1.25 mW transmitted power. This work shows an integration strategy from compact antenna design to its practical experimentation for enhanced data communication capability in future generation wearable electronics.

  18. High energy near- and far-field ptychographic tomography at the ESRF

    Science.gov (United States)

    da Silva, Julio C.; Haubrich, Jan; Requena, Guillermo; Hubert, Maxime; Pacureanu, Alexandra; Bloch, Leonid; Yang, Yang; Cloetens, Peter

    2017-09-01

    In high-resolution tomography, one needs high-resolved projections in order to reconstruct a high-quality 3D map of a sample. X-ray ptychography is a robust technique which can provide such high-resolution 2D projections taking advantage of coherent X-rays. This technique was used in the far-field regime for a fair amount of time, but it can now also be implemented in the near-field regime. In both regimes, the technique enables not only high-resolution imaging, but also high sensitivity to the electron density of the sample. The combination with tomography makes 3D imaging possible via ptychographic X-ray computed tomography (PXCT), which can provide a 3D map of the complex-valued refractive index of the sample. The extension of PXCT to X-ray energies above 15 keV is challenging, but it can allow the imaging of object opaque to lower energy. We present here the implementation and developments of high-energy near- and far-field PXCT at the ESRF.

  19. Comparison of predicted far-field temperatures for discrete and smeared heat sources

    International Nuclear Information System (INIS)

    Ryder, E.E.

    1992-01-01

    A fundamental concern in the design of the potential repository at Yucca Mountain. Nevada is the response of the host rock to the emplacement of heat-generating waste. The thermal perturbation of the rock mass has implications regarding the structural, hydrologic. and geochemical performance of the potential repository. The phenomenological coupling of many of these performance aspects makes repository thermal modeling a difficult task. For many of the more complex, coupled models, it is often necessary to reduce the geometry of the potential repository to a smeared heat-source approximation. Such simplifications have impacts on induced thermal profiles that in turn may influence other predicted responses through one- or two-way thermal couplings. The effect of waste employment layout on host-rock thermal was chosen as the primary emphasis of this study. Using a consistent set of modeling and input assumptions, far-field thermal response predictions made for discrete-source as well as plate source approximations of the repository geometry. Input values used in the simulations are consistent with a design-basis a real power density (APD) of 80 kW/acre as would be achieved assuming a 2010 emplacement start date, a levelized receipt schedule, and a limitation on available area as published in previous design studies. It was found that edge effects resulting from general repository layout have a significant influence on the shapes and extents of isothermal profiles, and should be accounted for in far-field modeling efforts

  20. Far-field thermomechanical response of argillaceous rock to emplacement of a nuclear-waste repository

    International Nuclear Information System (INIS)

    McVey, D.F.; Thomas, R.K.; Lappin, A.R.

    1980-08-01

    Before heat-producing wastes can be emplaced safely in any argillaceous rock, it will be necessary to understand the far-field thermal and thermomechanical response of this rock to waste emplacement. This report presents the results of a first series of calculations aimed at estimating the far-field response of argillite to waste emplacement. Because the thermal and mechanical properties of argillite are affected by its content of expandable clay, its behavior is briefly compared and contrasted with that of a shale having the same matrix thermal properties, but containing no expandable clay. Under this assumption, modeled temperatures are the same for the two rock types at equivalent power densities and reflect the large dependence of in-situ temperatures on both initial power density and waste type. Thermomechanical calculations indicate that inclusion of contraction behavior of expandable clays in the assumed argillite thermal expansion behavior results, in some cases, in generation of a large zone in and near the repository that has undergone volumetric contraction but is surrounded by uniformly compressive stresses. Information available to date indicates that this contraction would likely result in locally increased fluid permeability and decreased in-situ thermal conductivity, but might well be advantageous as regards radionuclide retention, because of the increased surface area within the contracted zone. Assumption of continuous and positive expansion behavior for the shale eliminates the near-repository contraction and tensional zones, but results in near-surface tensional zones directly above the repository

  1. Agenesis of the right lobe of liver: a case report

    International Nuclear Information System (INIS)

    Han, Kun Soo; Chang, Jae Chun; Park, Bok Hwan

    1993-01-01

    Congenital agenesis of the right lobe of liver is a rare anomaly and only 33 cases have been reported. CT showed absence of the right lobe of liver and compensatory hypertrophy of the other lobe. We report the CT findings a new case of this anomaly with a review of the literatures

  2. Right azygos lobe occurring with fissural and lobation anomalies ...

    African Journals Online (AJOL)

    Background: The azygos lobe is a rare anomaly of the lung that is separated from the rest of the upper lobe by an azygos fissure. The lobe is encountered mostly in the right lung but a few cases have also been described in the left lung. It occurs at a frequency of 0.25-1% and has surgical and radiological importance.

  3. The extratemporal lobe epilepsies in the epilepsy monitoring unit

    Science.gov (United States)

    Dash, Deepa; Tripathi, Manjari

    2014-01-01

    Extratemporal lobe epilepsies (ETLE) are characterized by the epileptogenic foci outside the temporal lobe. They have a wide spectrum of semiological presentation depending upon the site of origin. They can arise from frontal, parietal, occipital lobes and from hypothalamic hamartoma. We discuss in this review the semiology of different types of ETLE encountered in the epilepsy monitoring unit. PMID:24791090

  4. Recurrent diarrhea as a manifestation of temporal lobe epilepsy

    Directory of Open Access Journals (Sweden)

    Tomohiko Murai

    2014-01-01

    Full Text Available A woman with temporal lobe epilepsy manifesting with repeated episodes of sudden diarrhea and loss of consciousness is reported. A 63-year-old, right-handed female presented with chief complaints of sudden diarrhea and loss of consciousness for almost three decades. The first attack occurred in her 30s, and similar attacks repeated several times in a year. Her attacks comprised abrupt abdominal discomfort, diarrhea, sudden emergence of old memories relating to when she had played with her brother in her childhood, and loss of consciousness during defecation. She had no convulsion or automatism and fully recovered in a few minutes. Every time she was transferred to emergency hospital by ambulance, she had examinations such as blood test, head computed tomography, electrocardiogram, abdominal ultrasound, and electroencephalography (EEG, but no specific diagnosis was made. On admission to our hospital, vital signs, neurological examination, and blood tests did not show abnormal findings. During long-term video-EEG monitoring for 40 h, she had no habitual event. Interictal EEG showed intermittent irregular delta waves and sharp regional transients in the left anterio-midtemporal area. Sharp transients were not as outstanding from background activities as to be defined as epileptiform discharges, but they were reproducible in morphology and distribution and appeared not only in sleep but also in wakefulness. Brain magnetic resonance imaging was unremarkable. Single-photon emission computed tomography showed a decrease of blood flow in the left frontal and temporal lobes. Wechsler Adult Intelligence Scale—III showed a decline of verbal comprehension. We concluded that the patient was suffering from partial epilepsy originating from the left temporal lobe. Carbamazepine markedly improved her seizures. Temporal lobe epilepsy can manifest with diverse autonomic symptoms and signs. Abdominal sensations often herald the onset of epileptic seizures

  5. Serotonin modulation of CHH secretion by isolated cells of the crayfish retina and optic lobe.

    Science.gov (United States)

    Escamilla-Chimal, Elsa G; Hiriart, Marcia; Sánchez-Soto, Ma Carmen; Fanjul-Moles, Maria Luisa

    2002-02-01

    The authors used the reverse hemolytic plaque assay to investigate whether single retinal and optic lobe cells of juvenile and adult crayfish secrete crustacean hyperglycemic hormone (CHH) and whether the secretion rate depends on extracellular serotonin (5-HT) concentration. Nearly 25% of individual retinal and optic lobe cells of juvenile and adult organisms secrete CHH in response to KCl depolarization. In this condition, CHH secretion increased as a function of 5-HT concentration. In both cases, the dose-response curve indicates two different populations of CHH-secreting cells. Juveniles showed a higher CHH secretion index than did adult organisms, demonstrating a developmental interstage variation of CHH secretion. The authors conclude that (1) retinal CHH-secreting cells correspond to a population of retinal tapetal cells and (2) optic lobe CHH-secreting cells correspond to two subpopulations of CHH of medulla terminalis-X organ.

  6. The contribution of the parietal lobes to speaking and writing.

    Science.gov (United States)

    Brownsett, Sonia L E; Wise, Richard J S

    2010-03-01

    The left parietal lobe has been proposed as a major language area. However, parietal cortical function is more usually considered in terms of the control of actions, contributing both to attention and cross-modal integration of external and reafferent sensory cues. We used positron emission tomography to study normal subjects while they overtly generated narratives, both spoken and written. The purpose was to identify the parietal contribution to the modality-specific sensorimotor control of communication, separate from amodal linguistic and memory processes involved in generating a narrative. The majority of left and right parietal activity was associated with the execution of writing under visual and somatosensory control irrespective of whether the output was a narrative or repetitive reproduction of a single grapheme. In contrast, action-related parietal activity during speech production was confined to primary somatosensory cortex. The only parietal area with a pattern of activity compatible with an amodal central role in communication was the ventral part of the left angular gyrus (AG). The results of this study indicate that the cognitive processing of language within the parietal lobe is confined to the AG and that the major contribution of parietal cortex to communication is in the sensorimotor control of writing.

  7. A new fold-cross metal mesh filter for suppressing side lobe leakage in terahertz region

    Science.gov (United States)

    Lu, Changgui; Qi, Zhengqing; Guo, Wengao; Cui, Yiping

    2018-04-01

    In this paper we propose a new type of fold-cross metal mesh band pass filter, which keeps diffraction side lobe far away from the main transmission peak and shows much better side lobe suppression. Both experimental and theoretical studies are made to analyze the mechanism of side lobe. Compared to the traditional cross filter, the fold-cross filter has a much lower side lobe with almost the same central frequency, bandwidth and highest transmission about 98%. Using the photolithography and electroplating techniques, we experimentally extend the distance between the main peak and diffraction side lobe to larger than 1 THz for the fold-cross filter, which is two times larger than the cross filter while maintaining the main peak transmissions of 89% at 1.25 THz for the two structures. This type of single layer substrate-free fold-cross metal structure shows better design flexibility and structure reliability with the introduction of fold arms for metal mesh band pass filters.

  8. Cephalic aura after frontal lobe resection.

    Science.gov (United States)

    Kakisaka, Yosuke; Jehi, Lara; Alkawadri, Rafeed; Wang, Zhong I; Enatsu, Rei; Mosher, John C; Dubarry, Anne-Sophie; Alexopoulos, Andreas V; Burgess, Richard C

    2014-08-01

    A cephalic aura is a common sensory aura typically seen in frontal lobe epilepsy. The generation mechanism of cephalic aura is not fully understood. It is hypothesized that to generate a cephalic aura extensive cortical areas need to be excited. We report a patient who started to have cephalic aura after right frontal lobe resection. Magnetoencephalography (MEG) showed interictal spike and ictal change during cephalic aura, both of which were distributed in the right frontal region, and the latter involved much more widespread areas than the former on MEG sensors. The peculiar seizure onset pattern may indicate that surgical modification of the epileptic network was related to the appearance of cephalic aura. We hypothesize that generation of cephalic aura may be associated with more extensive cortical involvement of epileptic activity than that of interictal activity, in at least a subset of cases. Copyright © 2014 Elsevier Ltd. All rights reserved.

  9. Dynamic perfusion patterns in temporal lobe epilepsy

    Energy Technology Data Exchange (ETDEWEB)

    Dupont, Patrick; Paesschen, Wim van [KU Leuven/UZ Gasthuisberg, Nuclear Medicine, Medical Imaging Center and Neurology, Leuven (Belgium); Zaknun, John J. [International Atomic Energy Agency (IAEA), Nuclear Medicine Section, Division of Human Health, Wagramer Strasse 5, PO BOX 200, Vienna (Austria); University Hospital of Innsbruck, Department of Nuclear Medicine, Innsbruck (Austria); Maes, Alex [KU Leuven/UZ Gasthuisberg, Nuclear Medicine, Medical Imaging Center and Neurology, Leuven (Belgium); AZ Groeninge, Nuclear Medicine, Kortrijk (Belgium); Tepmongkol, Supatporn; Locharernkul, Chaichon [Chulalongkorn University, Nuclear Medicine and Neurology, Bangkok (Thailand); Vasquez, Silvia; Carpintiero, Silvina [Fleni Instituto de Investigaciones Neurologicas, Nuclear Medicine, Buenos Aires (Argentina); Bal, C.S. [All India Institute of Medical Sciences, Nuclear Medicine, New Delhi (India); Dondi, Maurizio [International Atomic Energy Agency (IAEA), Nuclear Medicine Section, Division of Human Health, Wagramer Strasse 5, PO BOX 200, Vienna (Austria); Ospedale Maggiore, Nuclear Medicine, Bologna (Italy)

    2009-05-15

    To investigate dynamic ictal perfusion changes during temporal lobe epilepsy (TLE). We investigated 37 patients with TLE by ictal and interictal SPECT. All ictal injections were performed within 60 s of seizure onset. Statistical parametric mapping was used to analyse brain perfusion changes and temporal relationships with injection time and seizure duration as covariates. The analysis revealed significant ictal hyperperfusion in the ipsilateral temporal lobe extending to subcortical regions. Hypoperfusion was observed in large extratemporal areas. There were also significant dynamic changes in several extratemporal regions: ipsilateral orbitofrontal and bilateral superior frontal gyri and the contralateral cerebellum and ipsilateral striatum. The study demonstrated early dynamic perfusion changes in extratemporal regions probably involved in both propagation of epileptic activity and initiation of inhibitory mechanisms. (orig.)

  10. Nocturnal frontal lobe epilepsy in mucopolysaccharidosis.

    Science.gov (United States)

    Bonanni, Paolo; Volzone, Anna; Randazzo, Giovanna; Antoniazzi, Lisa; Rampazzo, Angelica; Scarpa, Maurizio; Nobili, Lino

    2014-10-01

    Nocturnal frontal lobe epilepsy (NFLE) is an epileptic syndrome that is primarily characterized by seizures with motor signs occurring almost exclusively during sleep. We describe 2 children with mucopolysaccharidosis (MPS) who were referred for significant sleep disturbance. Long term video-EEG monitoring (LT-VEEGM) demonstrated sleep-related hypermotor seizures consistent with NFLE. No case of sleep-related hypermotor seizures has ever been reported to date in MPS. However, differential diagnosis with parasomnias has been previously discussed. The high frequency of frontal lobe seizures causes sleep fragmentation, which may result in sleep disturbances observed in at least a small percentage of MPS patients. We suggest monitoring individuals with MPS using periodic LT-VEEGM, particularly when sleep disorder is present. Moreover, our cases confirm that NFLE in lysosomal storage diseases may occur, and this finding extends the etiologic spectrum of NFLE. Copyright © 2014 The Japanese Society of Child Neurology. Published by Elsevier B.V. All rights reserved.

  11. MR imaging of temporal lobe meningoencephalocele

    International Nuclear Information System (INIS)

    Tampieri, D.; Leblanc, R.; Melangon, D.; del-Carpio-O'Donovan, R.; Ethier, R.

    1991-01-01

    Basal meningoencephaloceles represent a rare entity, and they may be associated with a variety of midline cerebral abnormalities. The classification of basal meningoencephaloceles is related to their anatomic location. This paper reports experience in 3 patients, 2 who have temporal lobe epilepsy and a bone defect in the region of the foramen rotondum. In these 2 patients the encephalocele and its covering were protruding into the pterygopalatine fossa without any orbital involvement. The third patient presented with cerebrospinal fluid rhinorrhea caused by a transsphenoidal meningoencephalocele. MR imaging is the examination of choice for detecting these lesions since it allows for the visualization of the encephalocele and its meningeal covering as well as the bone defect and associated lesions in the temporal lobes

  12. Integrating what and when across the primate medial temporal lobe.

    Science.gov (United States)

    Naya, Yuji; Suzuki, Wendy A

    2011-08-05

    Episodic memory or memory for the detailed events in our lives is critically dependent on structures of the medial temporal lobe (MTL). A fundamental component of episodic memory is memory for the temporal order of items within an episode. To understand the contribution of individual MTL structures to temporal-order memory, we recorded single-unit activity and local field potential from three MTL areas (hippocampus and entorhinal and perirhinal cortex) and visual area TE as monkeys performed a temporal-order memory task. Hippocampus provided incremental timing signals from one item presentation to the next, whereas perirhinal cortex signaled the conjunction of items and their relative temporal order. Thus, perirhinal cortex appeared to integrate timing information from hippocampus with item information from visual sensory area TE.

  13. Recovering an elastic obstacle containing embedded objects by the acoustic far-field measurements

    Science.gov (United States)

    Qu, Fenglong; Yang, Jiaqing; Zhang, Bo

    2018-01-01

    Consider the inverse scattering problem of time-harmonic acoustic waves by a 3D bounded elastic obstacle which may contain embedded impenetrable obstacles inside. We propose a novel and simple technique to show that the elastic obstacle can be uniquely recovered by the acoustic far-field pattern at a fixed frequency, disregarding its contents. Our method is based on constructing a well-posed modified interior transmission problem on a small domain and makes use of an a priori estimate for both the acoustic and elastic wave fields in the usual H 1-norm. In the case when there is no obstacle embedded inside the elastic body, our method gives a much simpler proof for the uniqueness result obtained previously in the literature (Natroshvili et al 2000 Rend. Mat. Serie VII 20 57-92 Monk and Selgas 2009 Inverse Problems Imaging 3 173-98).

  14. Electromagnetic signatures of far-field gravitational radiation in the 1 + 3 approach

    International Nuclear Information System (INIS)

    Chua, Alvin J K; Cañizares, Priscilla; Gair, Jonathan R

    2015-01-01

    Gravitational waves (GWs) from astrophysical sources can interact with background electromagnetic fields, giving rise to distinctive and potentially detectable electromagnetic signatures. In this paper, we study such interactions for far-field gravitational radiation using the 1 + 3 approach to relativity. Linearized equations for the electromagnetic field on perturbed Minkowski space are derived and solved analytically. The inverse Gertsenshteĭn conversion of GWs in a static electromagnetic field is rederived, and the resultant electromagnetic radiation is shown to be significant for highly magnetized pulsars in compact binary systems. We also obtain a variety of nonlinear interference effects for interacting gravitational and electromagnetic waves, although wave–wave resonances previously described in the literature are absent when the electric–magnetic self-interaction is taken into account. The fluctuation and amplification of electromagnetic energy flux as the GW strength increases towards the gravitational–electromagnetic frequency ratio is a possible signature of gravitational radiation from extended astrophysical sources. (paper)

  15. New evidence for "far-field" Holocene sea level oscillations and links to global climate records

    Science.gov (United States)

    Leonard, N. D.; Welsh, K. J.; Clark, T. R.; Feng, Y.-x.; Pandolfi, J. M.; Zhao, J.-x.

    2018-04-01

    Rising sea level in the coming century is of significant concern, yet predicting relative sea level change in response to eustatic sea level variability is complex. Potential analogues are provided by the recent geological past but, until recently, many sea level reconstructions have been limited to millennial scale interpretations due to age uncertainties and paucity in proxy derived records. Here we present a sea level history for the tectonically stable "far-field" Great Barrier Reef, Australia, derived from 94 high precision uranium-thorium dates of sub-fossil coral microatolls. Our results provide evidence for at least two periods of relative sea level instability during the Holocene. These sea level oscillations are broadly synchronous with Indo-Pacific negative sea surface temperature anomalies, rapid global cooling events and glacial advances. We propose that the pace and magnitude of these oscillations are suggestive of eustatic/thermosteric processes operating in conjunction with regional climatic controls.

  16. Surface pressure fluctuations on aircraft flaps and their correlation with far-field noise

    Science.gov (United States)

    Guo, Y. P.; Joshi, M. C.; Bent, P. H.; Yamamoto, K. J.

    2000-07-01

    This paper discusses unsteady surface pressures on aircraft flaps and their correlation with far-field noise. Analyses are made of data from a 4.7% DC-10 aircraft model test, conducted in the 40 × 80 feet wind tunnel at NASA Ames Research Center. Results for various slat/wing/flap configurations and various flow conditions are discussed in detail to reveal major trends in surface pressure fluctuations. Spectral analysis, including cross-correlation/coherence, both among unsteady surface pressures and between far-field noise and near-field fluctuations, is used to reveal the most coherent motions in the near field and identify potential sources of noise related to flap flows. Dependencies of surface pressure fluctuations on mean flow Mach numbers, flap settings and slat angles are discussed. Dominant flow features in flap side edge regions, such as the formation of double-vortex structures, are shown to manifest themselves in the unsteady surface pressures as a series of spectral humps. The spectral humps are shown to correlate well with the radiated noise, indicating the existence of major noise sources in flap side edge regions. Strouhal number scaling is used to collapse the data with satisfactory results. The effects of flap side edge fences on surface pressures are also discussed. It is shown that the application of fences effectively increases the thickness of the flaps so that the double-vortex structures have more time to evolve. As a result, the characteristic timescale of the unsteady sources increases, which in turn leads to a decrease in the dominant frequency of the source process. Based on this, an explanation is proposed for the noise reduction mechanism of flap side edge fences.

  17. Far-field divergence of a vectorial plane wave diffracted by a circular aperture from the vectorial structure

    International Nuclear Information System (INIS)

    Zhou Guo-Quan

    2011-01-01

    Based on the vectorial structure of an electromagnetic wave, the analytical and concise expressions for the TE and TM terms of a vectorial plane wave diffracted by a circular aperture are derived in the far-field. The expressions of the energy flux distributions of the TE term, the TM term and the diffracted plane wave are also presented. The ratios of the power of the TE and TM terms to that of the diffracted plane wave are examined in the far-field. In addition, the far-field divergence angles of the TE term, the TM term and the diffracted plane wave, which are related to the energy flux distribution, are investigated. The different energy flux distributions of the TE and TM terms result in the discrepancy of their divergence angles. The influences of the linearly polarized angle and the radius of the circular aperture on the far-field divergence angles of the TE term, the TM term and the diffracted plane wave are discussed in detail. This research may promote the recognition of the optical propagation through a circular aperture. (electromagnetism, optics, acoustics, heat transfer, classical mechanics, and fluid dynamics)

  18. Efficient EBE treatment of the dynamic far-field in non-linear FE soil-structure interaction analyses

    NARCIS (Netherlands)

    Crouch, R.S.; Bennett, T.

    2000-01-01

    This paper presents results and observations from the use of a rigorous method of treating the dynamic far-field as part of a non-linear FE analysis. The technique de-veloped by Wolf and Song (referred to as the Scaled Boundary Finite-Element Method) is incorporated into a 3-D time-domain analysis

  19. Assessment of the Bordas-Carnot Losses within the diffuser of tidal turbines using far-field and near-field CFD models.

    Science.gov (United States)

    Hajaali, Arthur

    2017-04-01

    This project has for ambition to analyse and further the general understanding on cross-flows interactions and behaviours at the mouth of a mini/small tidal hydropower plant and a river. Although, the study of these interactions could benefit and find applications in multiple hydraulic problems, this project concentrates its focus on the influence of the transposed turbulences generated by the cross-flow into the diffuser. These eddies affect the overall performance and efficiency of the bulb-turbines by minimizing the pressure recovery. In the past, these turbulences were accounted with the implementation of the Bordas-Carnot losses coefficient for the design of tidal project using bulb-turbines. The bulb turbine technology has been the interest and subject of many scientific papers but most of them concentrate and narrow their focus on the design of the rotor, blades and combiner. This project wants to focus the design of the diffuser by performing an analysis on the development of eddies and the turbulences using computational fluid dynamic (CFD) models. The Severn estuary is endowed with one of the highest tidal range around the hemisphere. The first part of the research requires to select case studies sites such as Briton-Ferry to virtually design mini-tidal plant in 0-Dimentional (D), 2D and 3D modelling to study development and behaviour of turbulences within the diffuser. The far-field model represents the marine environment prior and after the structure where bulb turbines are located. The near-field modelling has allowed researcher to study at much higher resolution and precision the design of a single turbine feeding model with predetermined and fix boundary condition. For this reason, a near-field model is required to study in depth the behaviour and evolution of the turbulence with the diffuser. One of the main challenge and advancement of this research is to find a methodology and system to link the far-field and near-field modelling to produce an

  20. Analytical research of vibration and far-field acoustic radiation of cylindrical shell immersed at finite depth

    Directory of Open Access Journals (Sweden)

    GUO Wenjie

    2017-08-01

    Full Text Available Aiming at the current lack of analytical research concerning the cylindrical shell-flow field coupling vibration and sound radiation system under the influence of a free surface, this paper proposes an analytical method which solves the vibration response and far-field acoustic radiation of a finite cylindrical shell immersed at a finite depth. Based on the image method and Graf addition theorem, the analytical expression of the fluid velocity potential can be obtained, then combined with the energy functional of the variation method to deduce the shell-liquid coupling vibration equation, which can in turn solve the forced vibration response. The research shows that, compared with an infinite fluid, a free surface can increase at the same order of resonance frequency; but as the depth of immersion gradually increases, the mean square vibration velocity tends to become the same as that in an infinite fluid. Compared with numerical results from Nastran software, this shows that the present method is accurate and reliable, and has such advantages as a simple method and a small amount of calculation. The far-field radiated pressure can be obtained by the vibration response using the Fourier transformation and stationary phase method. The results indicate that the directivity and volatility of the far-field acoustic pressure of a cylindrical shell is similar to that of an acoustical dipole due to the free surface. However, the far-field acoustic pressure is very different from the vibration characteristics, and will not tend to an infinite fluid as the submerging depth increases. Compared with the numerical method, the method in this paper is simpler and has a higher computational efficiency. It enables the far-field acoustic radiation of an underwater cylindrical shell to be predicted quickly under the influence of external incentives and the free surface, providing guiding significance for acoustic research into the half space structure vibration

  1. Altered structural connectome in temporal lobe epilepsy.

    Science.gov (United States)

    DeSalvo, Matthew N; Douw, Linda; Tanaka, Naoaki; Reinsberger, Claus; Stufflebeam, Steven M

    2014-03-01

    To study differences in the whole-brain structural connectomes of patients with left temporal lobe epilepsy (TLE) and healthy control subjects. This study was approved by the institutional review board, and all individuals gave signed informed consent. Sixty-direction diffusion-tensor imaging and magnetization-prepared rapid acquisition gradient-echo (MP-RAGE) magnetic resonance imaging volumes were analyzed in 24 patients with left TLE and in 24 healthy control subjects. MP-RAGE volumes were segmented into 1015 regions of interest (ROIs) spanning the entire brain. Deterministic white matter tractography was performed after voxelwise tensor calculation. Weighted structural connectivity matrices were generated by using the pairwise density of connecting fibers between ROIs. Graph theoretical measures of connectivity networks were compared between groups by using linear models with permutation testing. Patients with TLE had 22%-45% reduced (P < .01) distant connectivity in the medial orbitofrontal cortex, temporal cortex, posterior cingulate cortex, and precuneus, compared with that in healthy subjects. However, local connectivity, as measured by means of network efficiency, was increased by 85%-270% (P < .01) in the medial and lateral frontal cortices, insular cortex, posterior cingulate cortex, precuneus, and occipital cortex in patients with TLE as compared with healthy subjects. This study suggests that TLE involves altered structural connectivity in a network that reaches beyond the temporal lobe, especially in the default mode network.

  2. Anterior Temporal Lobe Morphometry Predicts Categorization Ability

    Directory of Open Access Journals (Sweden)

    Béatrice Garcin

    2018-02-01

    Full Text Available Categorization is the mental operation by which the brain classifies objects and events. It is classically assessed using semantic and non-semantic matching or sorting tasks. These tasks show a high variability in performance across healthy controls and the cerebral bases supporting this variability remain unknown. In this study we performed a voxel-based morphometry study to explore the relationships between semantic and shape categorization tasks and brain morphometric differences in 50 controls. We found significant correlation between categorization performance and the volume of the gray matter in the right anterior middle and inferior temporal gyri. Semantic categorization tasks were associated with more rostral temporal regions than shape categorization tasks. A significant relationship was also shown between white matter volume in the right temporal lobe and performance in the semantic tasks. Tractography revealed that this white matter region involved several projection and association fibers, including the arcuate fasciculus, inferior fronto-occipital fasciculus, uncinate fasciculus, and inferior longitudinal fasciculus. These results suggest that categorization abilities are supported by the anterior portion of the right temporal lobe and its interaction with other areas.

  3. Prospective memory and frontal lobe function.

    Science.gov (United States)

    Neulinger, Kerryn; Oram, Joanne; Tinson, Helen; O'Gorman, John; Shum, David H K

    2016-01-01

    The study sought to examine the role of frontal lobe functioning in focal prospective memory (PM) performance and its relation to PM deficit in older adults. PM and working memory (WM) differences were studied in younger aged (n = 21), older aged (n = 20), and frontal injury (n = 14) groups. An event-based focal PM task was employed and three measures of WM were administered. The younger aged group differed from the other two groups in showing significantly higher scores on PM and on one of the WM measures, but there were no differences at a statistically significant level between the older aged group and the frontal injury groups on any of the memory measures. There were, however, some differences in correlations with a WM measure between groups. It is concluded that there are similarities and differences in the deficits in PM between older adults and patients with frontal lobe injury on focal as well as nonfocal PM tasks.

  4. [Normal aging of frontal lobe functions].

    Science.gov (United States)

    Calso, Cristina; Besnard, Jérémy; Allain, Philippe

    2016-03-01

    Normal aging in individuals is often associated with morphological, metabolic and cognitive changes, which particularly concern the cerebral frontal regions. Starting from the "frontal lobe hypothesis of cognitive aging" (West, 1996), the present review is based on the neuroanatomical model developed by Stuss (2008), introducing four categories of frontal lobe functions: executive control, behavioural and emotional self-regulation and decision-making, energization and meta-cognitive functions. The selected studies only address the changes of one at least of these functions. The results suggest a deterioration of several cognitive frontal abilities in normal aging: flexibility, inhibition, planning, verbal fluency, implicit decision-making, second-order and affective theory of mind. Normal aging seems also to be characterised by a general reduction in processing speed observed during neuropsychological assessment (Salthouse, 1996). Nevertheless many cognitive functions remain preserved such as automatic or non-conscious inhibition, specific capacities of flexibility and first-order theory of mind. Therefore normal aging doesn't seem to be associated with a global cognitive decline but rather with a selective change in some frontal systems, conclusion which should be taken into account for designing caring programs in normal aging.

  5. Accessory hepatic lobe in right lumbar region - an incidental finding.

    Science.gov (United States)

    Shrestha, M K; Ghartimagar, D; Ghosh, A

    2014-01-01

    An accessory lobe of liver is a rare congenital anomaly which can be detected incidentally or can even present as acute surgical emergency due to torsion. We report a case of accessory hepatic lobe in right lumbar region in a 21years old female who came for a ultrasound abdomen for lower abdominal pain. We report the importance of ultrasonography and Computed Tomogram (CT) scan for the diagnosis of accessory hepatic lobe.

  6. Unilateral spatial neglect due to right frontal lobe haematoma.

    OpenAIRE

    Maeshima, S; Funahashi, K; Ogura, M; Itakura, T; Komai, N

    1994-01-01

    Two patients with unilateral spatial neglect caused by right frontal lobe lesions underwent cerebral blood flow studies. A 54-year-old, right-handed woman developed left hemiplegia and frontal lobe neglect associated with cerebral haemorrhage after surgical excision of a frontal tumour. A 66-year-old, right-handed woman developed a haemorrhage in the right frontal lobe caused by rupture of an aneurysm. This was followed by left hemiplegia and frontal lobe neglect. In both cases, 123I-iodoamph...

  7. Surgical Considerations of Intractable Mesial Temporal Lobe Epilepsy

    Directory of Open Access Journals (Sweden)

    Warren W. Boling

    2018-02-01

    Full Text Available Surgery of temporal lobe epilepsy is the best opportunity for seizure freedom in medically intractable patients. The surgical approach has evolved to recognize the paramount importance of the mesial temporal structures in the majority of patients with temporal lobe epilepsy who have a seizure origin in the mesial temporal structures. For those individuals with medically intractable mesial temporal lobe epilepsy, a selective amygdalohippocampectomy surgery can be done that provides an excellent opportunity for seizure freedom and limits the resection to temporal lobe structures primarily involved in seizure genesis.

  8. Channel systems and lobe construction in the Mississippi Fan

    Science.gov (United States)

    Garrison, L. E.; Kenyon, Neil H.; Bouma, A.H.

    1982-01-01

    Morphological features on the Mississippi Fan in the eastern Gulf of Mexico were mapped using GLORIA II, a long-range side-scan sonar system. Prominent is a sinuous channel flanked by well-developed levees and occasional crevasse splays. The channel follows the axis and thickest part of the youngest fan lobe; seismic-reflection profiles offer evidence that its course has remained essentially constant throughout lobe development. Local modification and possible erosion of levees by currents indicates a present state of inactivity. Superficial sliding has affected part of the fan lobe, but does not appear to have been a factor in lobe construction. ?? 1982 A. M. Dowden, Inc.

  9. Occurrence of the lobe plasma at lunar distance

    International Nuclear Information System (INIS)

    Hardy, D.A.; Hills, H.K.; Freeman, J.W.

    1979-01-01

    Recent analysis has confirmed and expanded the characterization of the lobe plasma, the extension of the 'boundary layer' and 'plasma mantle' to lunar distances. Careful statistical analysis has verified that Magnetic Field (1MF). When the moon is in the dawnside of the northern lobe or duskside of the southern lobe, the probability for observation of the lobe plasma is greatly increased when, in the hour preceding, the IMF has had a positive y component. Conversely, when the moon is in the duskside of the northern lobe or dawnside of the southern lobe, the probability for observation is much increased when the IMF has a negative y component. Analysis of lobe plasma data in conjunction with high time resolution IMF data has shown the probability of observation also is greater with a southward pointing IMF. The observed correlations with the y and z components the IMF reflect the fact that the asymmetry and changes in magnitude of the polar cap electric field induced by the IMF extends to lunar distances and determines the depth into the tail to which the ions can drift. Generally, the lobe plasma is observed sporadically for a full day after the moon has entered the tail and a full day before the last magnetopause crossing as it exits the tail. An average extent of approx.8--10R/sub e/ inward from the magnetopause is inferred; however, the lobe plasma has been seen all across the tail

  10. The right hemisphere's contribution to discourse processing: A study in temporal lobe epilepsy.

    Science.gov (United States)

    Lomlomdjian, Carolina; Múnera, Claudia P; Low, Daniel M; Terpiluk, Verónica; Solís, Patricia; Abusamra, Valeria; Kochen, Silvia

    2017-08-01

    Discourse skills - in which the right hemisphere has an important role - enables verbal communication by selecting contextually relevant information and integrating it coherently to infer the correct meaning. However, language research in epilepsy has focused on single word analysis related mainly to left hemisphere processing. The purpose of this study was to investigate discourse abilities in patients with right lateralized medial temporal lobe epilepsy (RTLE) by comparing their performance to that of patients with left temporal lobe epilepsy (LTLE). 74 pharmacoresistant temporal lobe epilepsy (TLE) patients were evaluated: 34 with RTLE and 40 with LTLE. Subjects underwent a battery of tests that measure comprehension and production of conversational and narrative discourse. Disease related variables and general neuropsychological data were evaluated. The RTLE group presented deficits in interictal conversational and narrative discourse, with a disintegrated speech, lack of categorization and misinterpretation of social meaning. LTLE group, on the other hand, showed a tendency to lower performance in logical-temporal sequencing. RTLE patients showed discourse deficits which have been described in right hemisphere damaged patients due to other etiologies. Medial and anterior temporal lobe structures appear to link semantic, world knowledge, and social cognition associated areas to construct a contextually related coherent meaning. Copyright © 2017 Elsevier Inc. All rights reserved.

  11. Fetal intermediate lobe is stimulated by parturition.

    Science.gov (United States)

    Facchinetti, F; Lanzani, A; Genazzani, A R

    1989-11-01

    The fetal pituitary gland secretes beta-endorphin in blood in response to delivery. However, other forms of endorphin have recently been observed in the fetal pituitary, such as N-acetyl-beta-endorphin, which is devoid of opiate activity, and a desacetylated form of alpha-melanocyte-stimulating hormone. Both endorphins originate in the pituitary intermediate lobe. The sensitivity of this lobe to labor stress was assessed by the evaluation of beta-endorphin, N-acetyl-beta-endorphin, melanocyte-stimulating hormone, and desacetylated alpha-melanocyte-stimulating hormone in maternal plasma and cord blood in 11 cases of vaginal delivery and 10 cases of elective cesarean section without labor. Plasma peptide levels were determined by specific radioimmunoassays after extraction on Sep-Pak C-18 cartridges and high-performance liquid chromatography fractionation. Cord blood samples of infants delivered vaginally showed higher beta-endorphin (8.5 +/- 1.6 pmol/L, mean +/- SE) and desacetylated alpha-melanocyte-stimulating hormone (13.6 +/- 3.2 pmol/L) levels than those delivered by elective cesarean section (3.7 +/- 0.8 and 4.2 +/- 1.1 pmol/L, for beta-endorphin and desacetylated alpha-melanocyte-stimulating hormone, respectively). N-acetyl-beta-endorphin and alpha-melanocyte-stimulating hormone levels do not differ in relation to the mode of delivery. In maternal circulation beta-endorphin levels were higher in those delivered vaginally (5.2 pm 1) than in women who had cesarean sections (2.5 +/- 0.5 pmol/L), whereas no changes were found for the other peptides. In vaginal deliveries, the level of desacetylated alpha-melanocyte-stimulating hormone was higher in cord blood (13.6 +/- 3.2 pmol/L) than in maternal plasma (6.5 +/- 3 pmol/L); there were no significant differences with regard to the other peptides. Fetal and maternal levels of all the peptides were similar in cases of cesarean section. We conclude that parturition activates proopiomelanocortin peptide release from

  12. Thyroid Metastasis in Pyramidal Lobe from Renal Cell Carcinoma: A Case Report

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Hyung Seok; Kim, Dong Wook; Kim, Sang Su [Dept. of Radiology, Busan Paik Hospital, Inje University College of Medicine, Busan (Korea, Republic of); Jung, Soo Jin [Dept. of Pathology, Busan Paik Hospital, Inje University College of Medicine, Busan (Korea, Republic of)

    2011-06-15

    Thyroid metastasis is rare. The most common primary malignancy of thyroid metastasis worldwide is known to be renal cell carcinoma, but the most common primary malignancy in South Korea is breast cancer. Many studies have reported that primary renal cell carcinoma is almost unilateral and thyroid metastasis from renal cell carcinoma is a nearly ipsilateral, single lesion. We report a case of pyramidal lobe metastasis from renal cell carcinoma.

  13. Interictal brain SPECT in patients with medically refractory temporal lobe epilepsy

    International Nuclear Information System (INIS)

    Andraus, Maria Emilia Cosenza

    2000-06-01

    The brain single photon emission computed tomography (SPECT) is s functional neuroimaging method that can detect localized changes in cerebral blood flow. The temporal lobe epilepsy (TLE) is the most common epileptic syndrome in adults, and more than 50% are medically refractory. The SPECT can contribute to investigation of epileptogenic focus and is one of the methods of pre-surgical evaluation of these patients. (author)

  14. Coverage Extension via Side-Lobe Transmission in Multibeam Satellite System

    OpenAIRE

    Gharanjik, Ahmad; Kmieciak, Jarek; Shankar, Bhavani; Ottersten, Björn

    2017-01-01

    In this paper, we study feasibility of coverage extension of a multibeam satellite network by providing low-rate communications to terminals located outside the coverage of main beams. Focusing on the MEO satellite network, and using realistic link budgets from O3b networks, we investigate the performance of both forward and return-links for terminals stationed in the side lobes of the main beams. Particularly, multi-carrier transmission for forward-link and single carrier transmission for re...

  15. Implementation of the far-field method for calculation of added resistance using a high order finite-difference approximation on overlapping grids

    DEFF Research Database (Denmark)

    Amini Afshar, Mostafa; Bingham, Harry B.

    The far-field method for calculation of the wave drift force is implemented in the high order finitedifferenceseakeeping solver. The implementation is based on the Maruo formulation which employesthe Kochin function to obtain the complex amplitude of the velocity potential in the far-field. There......The far-field method for calculation of the wave drift force is implemented in the high order finitedifferenceseakeeping solver. The implementation is based on the Maruo formulation which employesthe Kochin function to obtain the complex amplitude of the velocity potential in the far...

  16. Non-paraxial contributions to the far-field pattern of surface-emitting lasers: a manifestation of the momentum-space wavefunctions of quantum billiards

    International Nuclear Information System (INIS)

    Yu, Y T; Huang, Y J; Chiang, P Y; Lin, Y C; Huang, K F; Chen, Y F

    2011-01-01

    We investigated experimentally non-paraxial contributions to the high-order far-field pattern of large-area vertical-cavity surface-emitting lasers in order to explore by analogy the momentum-space wave distributions of quantum billiards. Our results reveal that non-paraxial contributions significantly influence the morphology of the high-order far-field pattern. A fast reliable method is developed for transforming the experimental far-field patterns to the correct Fourier transform of the corresponding near-field lasing modes. In this way we visualize the momentum-space (p–q) wavefunctions of quantum billiards

  17. Video electroencephalogram telemetry in temporal lobe epilepsy

    Directory of Open Access Journals (Sweden)

    Jayanti Mani

    2014-01-01

    Full Text Available Temporal lobe epilepsy (TLE is the most commonly encountered medically refractory epilepsy. It is also the substrate of refractory epilepsy that gives the most gratifying results in any epilepsy surgery program, with a minimum use of resources. Correlation of clinical behavior and the ictal patterns during ictal behavior is mandatory for success at epilepsy surgery. Video electroencephalogram (EEG telemetry achieves this goal and hence plays a pivotal role in pre-surgical assessment. The role of telemetry is continuously evolving with the advent of digital EEG technology, of high-resolution volumetric magnetic resonance imaging and other functional imaging techniques. Most of surgical selection in patients with TLE can be done with a scalp video EEG monitoring. However, the limitations of the scalp EEG technique demand invasive recordings in a selected group of TLE patients. This subset of the patients can be a challenge to the epileptologist.

  18. The mirror mechanism in the parietal lobe.

    Science.gov (United States)

    Rizzolatti, Giacomo; Rozzi, Stefano

    2018-01-01

    The mirror mechanism is a basic mechanism that transforms sensory representations of others' actions into motor representations of the same actions in the brain of the observer. The mirror mechanism plays an important role in understanding actions of others. In the present chapter we discuss first the basic organization of the posterior parietal lobe in the monkey, stressing that it is best characterized as a motor scaffold, on the top of which sensory information is organized. We then describe the location of the mirror mechanism in the posterior parietal cortex of the monkey, and its functional role in areas PFG, and anterior, ventral, and lateral intraparietal areas. We will then present evidence that a similar functional organization is present in humans. We will conclude by discussing the role of the mirror mechanism in the recognition of action performed with tools. Copyright © 2018 Elsevier B.V. All rights reserved.

  19. Frontal Lobe Function in Chess Players

    Directory of Open Access Journals (Sweden)

    Vahid Nejati

    2012-05-01

    Full Text Available Chess is considered as a cognitive game because of severe engagement of the mental resources during playing. The purpose of this study is evaluation of frontal lobe function of chess players with matched non-players. Wisconsin Card Sorting Test (WCST data showed no difference between the player and non-player groups in preservation error and completed categories but surprisingly showed significantly lower grade of the player group in correct response. Our data reveal that chess players dont have any preference in any stage of Stroop test. Chess players dont have any preference in selective attention, inhibition and executive cognitive function. Chess players' have lower shifting abilities than non-players.

  20. Monocarboxylate transporters in temporal lobe epilepsy

    DEFF Research Database (Denmark)

    Lauritzen, Fredrik; Eid, Tore; Bergersen, Linda H

    2013-01-01

    Epilepsy is a serious neurological disorder that affects approximately 1 % of the general population, making it one of the most common disorders of the central nervous system. Furthermore, up to 40 % of all patients with epilepsy cannot control their seizures with current medications. More...... efficacious treatments for medication refractory epilepsy are therefore needed. A better understanding of the mechanisms that cause this disorder is likely to facilitate the discovery of such treatments. Impairment in cerebral energy metabolism has been proposed as a possible causative factor...... in the pathogenesis of temporal lobe epilepsy (TLE), which is one of the most common types of medication-refractory epilepsies in adults. In this review, we will discuss some of the current hypotheses regarding the possible causal relationship between brain energy metabolism and TLE. Emphasis will be placed...

  1. Xenomelia: a new right parietal lobe syndrome.

    Science.gov (United States)

    McGeoch, Paul D; Brang, David; Song, Tao; Lee, Roland R; Huang, Mingxiong; Ramachandran, V S

    2011-12-01

    Damage to the right parietal lobe has long been associated with various disorders of body image. The authors have recently suggested that an unusual behavioural condition in which otherwise rational individuals desire the amputation of a healthy limb might also arise from right parietal dysfunction. Four subjects who desired the amputation of healthy legs (two right, one left and one, at first, bilateral and then left only) were recruited and underwent magnetoencephalography (MEG) scans during tactile stimulation of sites above and below the desired amputation line. Regions of interest (ROIs) in each hemisphere (superior parietal lobule (SPL), inferior parietal lobule, S1, M1, insula, premotor cortex and precuneus) were defined using FreeSurfer software. Analysis of average MEG activity across the 40-140 ms post-stimulation timeframe was carried out using an unpaired t test. This revealed significantly reduced activation only in the right SPL ROI for the subjects' affected legs when compared with both subjects' unaffected legs and that of controls. The right SPL is a cortical area that appears ideally placed to unify disparate sensory inputs to create a coherent sense of having a body. The authors propose that inadequate activation of the right SPL leads to the unnatural situation in which the sufferers can feel the limb in question being touched without it actually incorporating into their body image, with a resulting desire for amputation. The authors introduce the term 'xenomelia' as a more appropriate name than apotemnophilia or body integrity identity disorder, for what appears to be an unrecognised right parietal lobe syndrome.

  2. Reconstruction of far-field tsunami amplitude distributions from earthquake sources

    Science.gov (United States)

    Geist, Eric L.; Parsons, Thomas E.

    2016-01-01

    The probability distribution of far-field tsunami amplitudes is explained in relation to the distribution of seismic moment at subduction zones. Tsunami amplitude distributions at tide gauge stations follow a similar functional form, well described by a tapered Pareto distribution that is parameterized by a power-law exponent and a corner amplitude. Distribution parameters are first established for eight tide gauge stations in the Pacific, using maximum likelihood estimation. A procedure is then developed to reconstruct the tsunami amplitude distribution that consists of four steps: (1) define the distribution of seismic moment at subduction zones; (2) establish a source-station scaling relation from regression analysis; (3) transform the seismic moment distribution to a tsunami amplitude distribution for each subduction zone; and (4) mix the transformed distribution for all subduction zones to an aggregate tsunami amplitude distribution specific to the tide gauge station. The tsunami amplitude distribution is adequately reconstructed for four tide gauge stations using globally constant seismic moment distribution parameters established in previous studies. In comparisons to empirical tsunami amplitude distributions from maximum likelihood estimation, the reconstructed distributions consistently exhibit higher corner amplitude values, implying that in most cases, the empirical catalogs are too short to include the largest amplitudes. Because the reconstructed distribution is based on a catalog of earthquakes that is much larger than the tsunami catalog, it is less susceptible to the effects of record-breaking events and more indicative of the actual distribution of tsunami amplitudes.

  3. Probabilistic tsunami hazard assessment at Seaside, Oregon, for near-and far-field seismic sources

    Science.gov (United States)

    Gonzalez, F.I.; Geist, E.L.; Jaffe, B.; Kanoglu, U.; Mofjeld, H.; Synolakis, C.E.; Titov, V.V.; Areas, D.; Bellomo, D.; Carlton, D.; Horning, T.; Johnson, J.; Newman, J.; Parsons, T.; Peters, R.; Peterson, C.; Priest, G.; Venturato, A.; Weber, J.; Wong, F.; Yalciner, A.

    2009-01-01

    The first probabilistic tsunami flooding maps have been developed. The methodology, called probabilistic tsunami hazard assessment (PTHA), integrates tsunami inundation modeling with methods of probabilistic seismic hazard assessment (PSHA). Application of the methodology to Seaside, Oregon, has yielded estimates of the spatial distribution of 100- and 500-year maximum tsunami amplitudes, i.e., amplitudes with 1% and 0.2% annual probability of exceedance. The 100-year tsunami is generated most frequently by far-field sources in the Alaska-Aleutian Subduction Zone and is characterized by maximum amplitudes that do not exceed 4 m, with an inland extent of less than 500 m. In contrast, the 500-year tsunami is dominated by local sources in the Cascadia Subduction Zone and is characterized by maximum amplitudes in excess of 10 m and an inland extent of more than 1 km. The primary sources of uncertainty in these results include those associated with interevent time estimates, modeling of background sea level, and accounting for temporal changes in bathymetry and topography. Nonetheless, PTHA represents an important contribution to tsunami hazard assessment techniques; viewed in the broader context of risk analysis, PTHA provides a method for quantifying estimates of the likelihood and severity of the tsunami hazard, which can then be combined with vulnerability and exposure to yield estimates of tsunami risk. Copyright 2009 by the American Geophysical Union.

  4. Hazard from far-field tsunami at Hilo: Earthquakes from the Ring of Fire

    Science.gov (United States)

    Arcas, D.; Weiss, R.; Titov, V.

    2007-12-01

    Historical data and modeling are used to study tsunami hazard at Hilo, Hawaii. Hilo has one of the best historical tsunami record in the US. Considering the tsunami observations from the early eighteen hundreds until today reveals that the number of observed events per decade depends on the awareness of tsunami events. The awareness appears to be a function of the observation techniques such as seismometers and communication devices, as well as direct measurements. Three time periods can be identified, in which the number of observed events increases from one event per decade in the first period to 7.7 in the second, to 9.4 events per decade in the third one. A total of 89 events from far-field sources have been encountered. In contrast only 11 events have been observed with sources in the near field. To remove this historical observation bias from the hazard estimate, we have complimented the historical analysis with a modeling study. We have carried out modeling of 1476 individual earthquakes along the subduction zones of the Pacific Ocean in four different magnitude levels (7.5, 8.2, 8.7 and 9.3). The maximum run up and maximum peak at the tide gauge is plotted for the different magnitude levels to reveal sensitive and source areas of tsunami waves for Hilo and a linear scaling of both parameters for small, but non-linear scaling for larger earthquakes

  5. EM Modeling of Far-Field Radiation Patterns for Antennas on the GMA-TT UAV

    Science.gov (United States)

    Mackenzie, Anne I.

    2015-01-01

    To optimize communication with the Generic Modular Aircraft T-Tail (GMA-TT) unmanned aerial vehicle (UAV), electromagnetic (EM) simulations have been performed to predict the performance of two antenna types on the aircraft. Simulated far-field radiation patterns tell the amount of power radiated by the antennas and the aircraft together, taking into account blockage by the aircraft as well as radiation by conducting and dielectric portions of the aircraft. With a knowledge of the polarization and distance of the two communicating antennas, e.g. one on the UAV and one on the ground, and the transmitted signal strength, a calculation may be performed to find the strength of the signal travelling from one antenna to the other and to check that the transmitted signal meets the receiver system requirements for the designated range. In order to do this, the antenna frequency and polarization must be known for each antenna, in addition to its design and location. The permittivity, permeability, and geometry of the UAV components must also be known. The full-wave method of moments solution produces the appropriate dBi radiation pattern in which the received signal strength is calculated relative to that of an isotropic radiator.

  6. ESTIMATION OF FAR-FIELD TSUNAMI POTENTIAL FOR THE CARIBBEAN COAST BASED ON NUMERICAL SIMULATION

    Directory of Open Access Journals (Sweden)

    Narcisse Zaibo

    2003-01-01

    Full Text Available The tsunami problem for the coast of the Caribbean basin is discussed. Briefly the historical data of tsunami in the Caribbean Sea are presented. Numerical simulation of potential tsunamis in the Caribbean Sea is performed in the framework of the nonlinear-shallow theory. The tsunami wave height distribution along the Caribbean Coast is computed. These results are used to estimate the far-field tsunami potential of various coastal locations in the Caribbean Sea. In fact, five zones with tsunami low risk are selected basing on prognostic computations, they are: the bay “Golfo de Batabano” and the coast of province “Ciego de Avila” in Cuba, the Nicaraguan Coast (between Bluefields and Puerto Cabezas, the border between Mexico and Belize, the bay “Golfo de Venezuela” in Venezuela. The analysis of historical data confirms that there was no tsunami in the selected zones. Also, the wave attenuation in the Caribbean Sea is investigated; in fact, wave amplitude decreases in an order if the tsunami source is located on the distance up to 1000 km from the coastal location. Both factors wave attenuation and wave height distribution should be taken into account in the planned warning system for the Caribbean Sea.

  7. The Study on Scattered Far-Field Analysis of Ultrasonic SH-Wave Using Boundary Element Method

    International Nuclear Information System (INIS)

    Lee, Joon Hyun; Lee, Seo Il

    1999-01-01

    It is well recognized that ultrasonic technique is one of the most common and reliable nondestructive evaluation techniques for quantitative estimation of defects in structures. For the quantitative and accurate estimation of internal defects, the characteristics of scattered ultrasonic wave fields must be understood. In this study. the scattered near-field and far-field due to a circular cavity embedded in infinite media subjected to incident SH-waves were calculated by the boundary element method. The frequency response of the scattered ultrasonic far-field was transformed into the time-domain signal by obtaining its inverse Fourier transform. It was found that the amplitude of time-domain signal decreases and its time delay increases as the distance between the detecting point of ultrasonic scattered field and the center of internal cavity increases

  8. Rotating superconductor magnet for producing rotating lobed magnetic field lines

    Science.gov (United States)

    Hilal, Sadek K.; Sampson, William B.; Leonard, Edward F.

    1978-01-01

    This invention provides a rotating superconductor magnet for producing a rotating lobed magnetic field, comprising a cryostat; a superconducting magnet in the cryostat having a collar for producing a lobed magnetic field having oppositely directed adjacent field lines; rotatable support means for selectively rotating the superconductor magnet; and means for energizing the superconductor magnet.

  9. Surgical anatomy of the pyramidal lobe and its significance in ...

    African Journals Online (AJOL)

    In diffuse thyroid diseases, the lobes were always pathologically involved and significantly longer. Conclusion. Since the pyramidal lobe is a normal component of the thyroid gland, of varying position and size, with pathological changes in benign and malignant diseases, it should always be examined during thyroid surgery ...

  10. MRI rare finding: Absence of the left liver lobe

    Directory of Open Access Journals (Sweden)

    Isabella Ceravolo

    Full Text Available We report a rare case of left liver lobe absence in an 80-year-old male patient discovered during an MRI scan. The main imaging features of this condition are briefly reviewed, together with its pathogenesis and the most common associations and differential diagnoses. Keywords: Left liver lobe, Liver abnormalities, Liver magnetic resonance imaging

  11. A Consensus Network of Gene Regulatory Factors in the Human Frontal Lobe

    Science.gov (United States)

    Berto, Stefano; Perdomo-Sabogal, Alvaro; Gerighausen, Daniel; Qin, Jing; Nowick, Katja

    2016-01-01

    Cognitive abilities, such as memory, learning, language, problem solving, and planning, involve the frontal lobe and other brain areas. Not much is known yet about the molecular basis of cognitive abilities, but it seems clear that cognitive abilities are determined by the interplay of many genes. One approach for analyzing the genetic networks involved in cognitive functions is to study the coexpression networks of genes with known importance for proper cognitive functions, such as genes that have been associated with cognitive disorders like intellectual disability (ID) or autism spectrum disorders (ASD). Because many of these genes are gene regulatory factors (GRFs) we aimed to provide insights into the gene regulatory networks active in the human frontal lobe. Using genome wide human frontal lobe expression data from 10 independent data sets, we first derived 10 individual coexpression networks for all GRFs including their potential target genes. We observed a high level of variability among these 10 independently derived networks, pointing out that relying on results from a single study can only provide limited biological insights. To instead focus on the most confident information from these 10 networks we developed a method for integrating such independently derived networks into a consensus network. This consensus network revealed robust GRF interactions that are conserved across the frontal lobes of different healthy human individuals. Within this network, we detected a strong central module that is enriched for 166 GRFs known to be involved in brain development and/or cognitive disorders. Interestingly, several hubs of the consensus network encode for GRFs that have not yet been associated with brain functions. Their central role in the network suggests them as excellent new candidates for playing an essential role in the regulatory network of the human frontal lobe, which should be investigated in future studies. PMID:27014338

  12. Determination of femtosecond-laser-induced refractive-index changes in an optical fiber from far-field measurements

    DEFF Research Database (Denmark)

    Savolainen, Juha-Matti; Grüner-Nielsen, Lars; Kristensen, Poul

    2014-01-01

    A new method for direct writing of localized, circularly symmetric refractive-index changes in optical fibers with a femtosecond laser is demonstrated. The refractive-index changes are characterized using a novel approach employing comparison of numerical simulations to the measured far......-field profiles of unmodified and modified fibers. From the analysis, a negative refractive-index change of −0.015 0.005 within a radius of 0.6 0.1 μm is determined....

  13. Liquid microdroplet as an optical component to achieve imaging of 100 nm nanostructures on a far-field microscope

    Science.gov (United States)

    Hou, Beibei; Zhang, Luning

    2018-05-01

    We demonstrate that placing liquid microdroplets on a sample surface enables probing of the evanescent wave, thus having super-resolution capability on a far-field optical microscope. A simple method to form diiodomethane (CH2I2) liquid microdroplets with diameters of 10–90 μm in water is proposed. These microdroplets can be used to image various nanostructured samples with a feature size of about 100 nm under white-light illumination.

  14. Supplementary CT temporal lobe cuts confer no worthwhile benefit

    International Nuclear Information System (INIS)

    Straiton, J.A.; Macpherson, P.; Teasdale, E.M.

    1991-01-01

    The value of angled temporal lobe cuts as a supplement to conventional head computed tomography (CT) has been assessed by comparing the diagnostic yield of standard axial and specific temporal lobe images (TLCT) in 62 patients with temporal lobe epilepsy and 87 with Alzheimer-type senile dementia. Fewer than one patient in six had structural abnormality in the temporal lobe most readily demonstrated by axial CT. Five patients with epilepsy and ten with dementia had changes demonstrated only by TLCT, reported on by one or other of a pair of observers. However such changes were of dubious clinical relevance, or arose as a result of artefact. In one patient with epilepsy and underlying neoplasm, axial CT was positive and TLCT false-negative. The routine addition of temporal lobe cuts to a conventional axial examination confers no added benefit to justify the prolonged examination time and increased radiation dose to the lens of the eye. (orig.)

  15. An Efficient Approach for Identifying Stable Lobes with Discretization Method

    Directory of Open Access Journals (Sweden)

    Baohai Wu

    2013-01-01

    Full Text Available This paper presents a new approach for quick identification of chatter stability lobes with discretization method. Firstly, three different kinds of stability regions are defined: absolute stable region, valid region, and invalid region. Secondly, while identifying the chatter stability lobes, three different regions within the chatter stability lobes are identified with relatively large time intervals. Thirdly, stability boundary within the valid regions is finely calculated to get exact chatter stability lobes. The proposed method only needs to test a small portion of spindle speed and cutting depth set; about 89% computation time is savedcompared with full discretization method. It spends only about10 minutes to get exact chatter stability lobes. Since, based on discretization method, the proposed method can be used for different immersion cutting including low immersion cutting process, the proposed method can be directly implemented in the workshop to promote machining parameters selection efficiency.

  16. A New Intermediate Far-Field Spot Design for Polar Direct Drive at the National Ignition Facility

    Science.gov (United States)

    Cao, D.; Marozas, J. A.; Collins, T. J. B.; Radha, P. B.; McKenty, P. W.

    2015-11-01

    New far-field spot shapes were required and subsequently designed for the intermediate phase plates that will be fielded at the National Ignition Facility for polar-direct-drive laser-coupling experiments. Two-dimensional DRACO simulations using the new far-field spot design, coupled with appropriate ring energies and beam pointing angles, achieve a high neutron yield-over-clean (YOC) ratio with a clean hot-spot radius averaging 50 μm and a convergence ratio (CR) above 17 when performed with a 1300- μm plastic shell target driven by a 700-kJ double-picket pulse. This meets the original design objectives of maintaining a clean hot spot with a CR of 17. The presented far-field spot shapes are based on an ignition polar-direct-drive configuration modeled with the iSNB nonlocal thermal transport model. In addition, the use of Multi-FM during the first two pickets does not hinder performance, but instead slightly improves the neutron yield. This material is based upon work supported by the Department of Energy National Nuclear Security Administration under Award Number DE-NA0001944.

  17. Far-field and Fresnel Liquid Crystal Geometric Phase Holograms via Direct-Write Photo-Alignment

    Directory of Open Access Journals (Sweden)

    Xiao Xiang

    2017-12-01

    Full Text Available We study computer-generated geometric-phase holograms (GPHs realized by photo-aligned liquid crystals, in both simulation and experiment. We demonstrate both far-field and Fresnel holograms capable of producing far-field and near-field images with preserved fidelity for all wavelengths. The GPHs are fabricated by patterning a photo-alignment layer (PAL using a direct-write laser scanner and coating the surface with a polymerizable liquid crystal (i.e., a reactive mesogen. We study various recording pixel sizes, down to 3 μm, that are easily recorded in the PAL. We characterize the fabricated elements and find good agreement with theory and numerical simulation. Because of the wavelength independent geometric phase, the (phase fidelity of the replay images is preserved for all wavelengths, unlike conventional dynamic phase holograms. However, governed by the diffraction equation, the size and location of a reconstructed image depends on the replay wavelength for far-field and near-field GPHs, respectively. These offer interesting opportunities for white-light holography.

  18. PET imaging in temporal lobe epilepsy

    International Nuclear Information System (INIS)

    Semah, F.

    2006-01-01

    The research projects on epilepsy addressed two main issues: the pathophysiology of the inter-ictal hypo-metabolism in temporal lobe epilepsy and the role of the basal ganglia in the control of seizure. Our research projects focused primarily on temporal lobe epilepsy: The pathophysiology of inter-ictal hypo-metabolism and its correlation with the epileptogenic network was investigated in patients with mesial temporal lobe epilepsy. Inter-ictal hypo-metabolism is commonly found in mesio-temporal lobe epilepsy (MTLE) but its pathophysiology remains incompletely understood. We hypothesized that metabolic changes reflect the preferential networks involved in ictal discharges. We analyzed the topography of inter-ictal hypo-metabolism according to electro-clinical patterns in 50 patients with unilateral hippocampal sclerosis (HS) and consistent features of MTLE. Based on electro-clinical correlations we identified 4 groups:1) mesial group characterized by mesial seizure onset without evidence of early spread beyond the temporal lobe; 2) anterior mesio-lateral group (AML) with early anterior spread, involving the anterior lateral temporal cortex and insulo-fronto-opercular areas; 3) widespread mesio-lateral group (WML) with widespread spread, involving both anterior and posterior lateral temporal and peri-sylvian areas; 4) bi-temporal group (BT) with early contralateral temporal spread. Results of FDG-PET imaging in each group were compared to control subjects using statistical parametric mapping software (SPM99). MRI data and surgical outcome in each group were compared to metabolic findings. Hypo-metabolism was limited to the hippocampal gyrus, the temporal pole and the insula in the mesial group. Gradual involvement of the lateral temporal cortex, the insula and the peri-sylvian areas was observed in the AML and WML groups. The BT group differed from the others by mild bi-temporal involvement, bilateral insular hypo-metabolism and longer epilepsy duration. MRI

  19. Photonic wires and trumpets for ultrabright single photon sources

    DEFF Research Database (Denmark)

    Gérard, Jean-Michel; Claudon, Julien; Bleuse, Joël

    2013-01-01

    as to tailor their radiation diagram in the far-field. We highlight the novel “photonic trumpet” geometry, which provides a clean Gaussian beam, and is much less sensitive to fabrication imperfections than the more common needle-like taper geometry. S4Ps based on a single QD in a PW with integrated bottom...

  20. Value of analyzing deep gray matter and occipital lobe perfusion to differentiate dementia with Lewy bodies from Alzheimer's disease.

    Science.gov (United States)

    Shimizu, Soichiro; Hanyu, Haruo; Hirao, Kentaro; Sato, Tomohiko; Iwamoto, Toshihiko; Koizumi, Kiyoshi

    2008-12-01

    Dementia with Lewy bodies (DLB) is generally characterized by a decrease in regional cerebral blood flow (rCBF) in the occipital lobe. However, not all patients with DLB have this feature. We explored characteristics of rCBF pattern changes to improve the identification of DLB, in addition to occipital hypoperfusion. The study population comprised 30 patients with probable DLB and 49 patients with probable Alzheimer's disease (AD) who underwent single-photon emission computed tomography. The data were analyzed using Neurological Statistical Image Analysis Software (NEUROSTAT). We established a template of the region of interest (ROI) presenting the parietal lobe, posterior cingulate, striatum, thalamus, and occipital lobe on the standard brain atlas. We then compared the mean Z scores in each ROI between DLB and AD. Moreover, we investigated the value of analyzing relative rCBF changes in both the deep gray matter and occipital lobe in differentiating DLB from AD. The DLB group showed a significant relative rCBF increase in the bilateral striatum and thalamus, and a significant relative rCBF decrease in the bilateral occipital lobe when compared with the AD group. Receiver-operating characteristic analysis revealed that determining the hyperperfusion in the thalamus together with the hypoperfusion in the occipital lobe enabled a more accurate differentiation between DLB and AD than studying individual areas. Studying the relative increase of rCBF in the deep gray matter, and the relative decrease of that in the occipital lobe achieved a high differentiation between DLB and AD. This suggests that determining both an increase and a decrease in rCBF pattern may be important in differentiating between the two diseases.

  1. Metabolic Hyperactivity of the Medial Posterior Parietal Lobes in Psychogenic Tremor

    Directory of Open Access Journals (Sweden)

    Peter Hedera

    2012-05-01

    Full Text Available Background: The pathophysiology of psychogenic movement disorders, including psychogenic tremor (PT, is only emerging. Case Report: This is a single case report of a patient who met diagnostic criteria for PT. He underwent positron emission tomography (PET of brain with 18F-deoxyglucose at resting state. His PET study showed symmetrically increased 18F-deoxyglucose uptake in both posterior medial parietal lobes. There was no corresponding abnormality on structural imaging. Discussion: Hypermetabolism of the medial aspects of posterior parietal lobes bilaterally may reflect abnormal activity of sensory integration that is important in the pathogenesis of PT. This further supports the idea that non-organic movement disorders may be associated with detectable functional brain abnormalities.

  2. Comparison of Far-field Noise for Three Significantly Different Model Turbofans

    Science.gov (United States)

    Woodward, Richard P.

    2008-01-01

    Far-field noise sound power level (PWL) spectra and overall sound pressure level (OASPL) directivities were compared for three significantly different model fan stages which were tested in the NASA Glenn 9 15 Low Speed Wind Tunnel. The test fans included the Advanced Ducted Propulsor (ADP) Fan1, the baseline Source Diagnostic Test (SDT) fan, and the Quiet High Speed Fan2 (QHSF2). These fans had design rotor tangential tip speeds from 840 to 1474 ft/s and stage pressure ratios from 1.29 to 1.82. Additional parameters included rotor-stator spacing, stator sweep, and downstream support struts. Acoustic comparison points were selected on the basis of stage thrust. Acoustic results for the low tip speed/low pressure ratio fan (ADP Fan1) were thrust-adjusted to show how a geometrically-scaled version of this fan might compare at the higher design thrust levels of the other two fans. Lowest noise levels were typically observed for ADP Fan1 (which had a radial stator) and for the intermediate tip speed fan (Source Diagnostics Test, SDT, R4 rotor) with a swept stator. Projected noise levels for the ADP fan to the SDT swept stator configuration at design point conditions showed the fans to have similar noise levels. However, it is possible that the ADP fan could be 2 to 3 dB quieter with incorporation of a swept stator. Benefits of a scaled ADP fan include avoidance of multiple pure tones associated with transonic and higher blade tip speeds. Penalties of a larger size ADP fan would include increased nacelle size and drag.

  3. The parietal lobe and the vestibular system.

    Science.gov (United States)

    Dieterich, Marianne; Brandt, Thomas

    2018-01-01

    The vestibular cortex differs in various ways from other sensory cortices. It consists of a network of several distinct and separate temporoparietal areas. Its core region, the parietoinsular vestibular cortex (PIVC), is located in the posterior insula and retroinsular region and includes the parietal operculum. The entire network is multisensory (in particular, vestibular, visual, and somatosensory). The peripheral and central vestibular systems are bilaterally organized; there are various pontomesencephalic brainstem crossings and at least two transcallosal connections of both hemispheres, between the PIVC and the motion-sensitive visual cortex areas, which also mediate vestibular input. Structural and functional vestibular dominance characterizes the right hemisphere in right-handers and the left hemisphere in left-handers. This explains why right-hemispheric lesions in right-handers more often generally cause hemispatial neglect and the pusher syndrome, both of which involve vestibular function. Vestibular input also contributes to cognition and may determine individual lateralization of brain functions such as handedness. Bilateral organization is a major key to understanding cortical functions and disorders, for example, the visual-vestibular interaction that occurs in spatial orientation. Although the vestibular cortex is represented in both hemispheres, there is only one global percept of body position and motion. The chiefly vestibular aspects of the multiple functions and disorders of the parietal lobe dealt with in this chapter cannot be strictly separated from various multisensory vestibular functions within the entire brain. Copyright © 2018 Elsevier B.V. All rights reserved.

  4. Extrahippocampal Desynchronization in Nonlesional Temporal Lobe Epilepsy

    Directory of Open Access Journals (Sweden)

    Jesús Pastor

    2012-01-01

    Full Text Available Although temporal lobe epilepsy (TLE is traditionally associated with both hypersynchronous activity in the form of interictal epileptic discharges and hippocampal sclerosis, recent findings suggest that desynchronization also plays a central role in the dynamics of this pathology. The objective of this work is to show the imbalance existing between mesial activities in patients suffering from mesial TLE, with normal mesial structures. Foramen ovale recordings from six patients with mesial TLE and one with lateral TLE were analyzed through a cluster analysis and synchronization matrices. None of the patients present findings in the MRI presurgical evaluation. Numerical analysis was carried out in three different situations: awake and sleep interictal and also during the preictal stage. High levels of desynchronization ipsilateral to the epileptic side were present in mesial TLE patients. Low levels of desynchronization were present in the lateral TLE patient during the interictal stage and almost zero in the preictal stage. Implications of these findings in relation with seizure spreading are discussed.

  5. Estimating nitrogen loading and far-field dispersal potential from background sources and coastal finfish aquaculture: A simple framework and case study in Atlantic Canada

    Science.gov (United States)

    McIver, R.; Milewski, I.; Loucks, R.; Smith, R.

    2018-05-01

    Far-field nutrient impacts associated with finfish aquaculture have been identified as a topic of concern for regulators, managers, scientists, and the public for over two decades but disentangling aquaculture impacts from those caused by other natural and anthropogenic sources has impeded the development of monitoring metrics and management plans. We apply a bulk, steady-state nitrogen loading model (NLM) framework to estimate the annual input of Total Dissolved Nitrogen (TDN) from point and non-point sources to the watershed surrounding Port Mouton Bay, Nova Scotia (Canada). We then use the results of the NLM together with estimates of dissolved inorganic nitrogen (DIN) loading from a sea-cage trout farm in the Bay and progressive vector diagrams to illustrate potential patterns of DIN dispersal from the trout farm. Our estimated anthropogenic nitrogen contribution to Port Mouton Bay from all terrestrial and atmospheric sources is ∼211,703 kg TDN/year with atmospheric deposition accounting for almost all (98.6%). At a stocking level of ∼400,000 rainbow trout, the Port Mouton Bay sea-cage farm increases the annual anthropogenic TDN loading to the bay by 14.4% or 30,400 kg. Depending on current flow rates, nitrogen flux from the trout farm can be more than double the background concentrations of TDN near the farm site. Although it is unlikely that nitrogen loading from this single fish farm is saturating the DIN requirements of the entire bay, progressive vector diagrams suggest that the dispersal potential may be insufficient to mitigate potential symptoms of eutrophication associated with nitrogen fluxes. We present an accessible and user-friendly tool for managers to estimate baseline nutrient loading in relation to aquaculture and our use of progressive vector diagrams illustrate a practical and simple method for characterizing potential nutrient dispersal based on local conditions and spatial scales. Our study joins numerous studies which have highlighted

  6. Map reading, navigating from maps, and the medial temporal lobe.

    Science.gov (United States)

    Urgolites, Zhisen J; Kim, Soyun; Hopkins, Ramona O; Squire, Larry R

    2016-12-13

    We administered map-reading tasks in which participants navigated an array of marks on the floor by following paths on hand-held maps that made up to nine turns. The burden on memory was minimal because the map was always available. Nevertheless, because the map was held in a fixed position in relation to the body, spatial computations were continually needed to transform map coordinates into geographical coordinates as participants followed the maps. Patients with lesions limited to the hippocampus (n = 5) performed similar to controls at all path lengths (experiment 1). They were also intact at executing single moves to an adjacent location, even when trials began by facing in a direction that put the map coordinates and geographical coordinates into conflict (experiment 2). By contrast, one patient with large medial temporal lobe (MTL) lesions performed poorly overall in experiment 1 and poorly in experiment 2 when trials began by facing in the direction that placed the map coordinates and geographical coordinates in maximal conflict. Directly after testing, all patients were impaired at remembering factual details about the task. The findings suggest that the hippocampus is not needed to carry out the spatial computations needed for map reading and navigating from maps. The impairment in map reading associated with large MTL lesions may depend on damage in or near the parahippocampal cortex.

  7. Emitting far-field multicolor patterns and characters through plastic diffractive micro-optics elements illuminated by common Gaussian lasers in the visible range.

    Science.gov (United States)

    Zhang, Xinyu; Li, Hui; Liu, Kan; Luo, Jun; Xie, Changsheng; Ji, An; Zhang, Tianxu

    2011-04-01

    Far-field multicolor patterns and characters are emitted effectively in a relatively wide and deep spatial region by plastic diffractive micro-optics elements (DMOEs), which are illuminated directly by common Gaussian lasers in the visible range. Phase-only DMOEs are composed of a large number of fine step-shaped phase microstructures distributed sequentially over the plastic wafer selected. The initial DMOEs in silicon wafer are fabricated by an innovative technique with a combination of a single-mask ultraviolet photolithography and low-cost and rapid wet KOH etching. The fabricated silicon DMOEs are further converted into a nickel mask by the conventional electrochemical method, and they are finally transferred onto the surface of the plastic wafer through mature hot embossing. Morphological measurements show that the surface roughness of the plastic DMOEs is in the nanometer range, and the feature height of the phase steps in diffractive elements is in the submicrometer scale, which can be designed and adjusted flexibly according to requirements. The dimensions of the DMOEs can be changed from the order of millimeters to centimeters. A large number of pixel phase microstructures with a square microappearance employed to construct the phase-only DMOEs are created by the Gerchberg-Saxton algorithm, according to the target patterns and characters and common Gaussian lasers manipulated by the DMOEs fabricated. © 2011 Optical Society of America

  8. Papillary Carcinoma Arising from the Pyramidal Lobe of the Thyroid

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hyun Gi; Lee, Sarah; Kim, Eun Kyung; Moon, Hee Jung; Kwak, Jin Young [Severance Hospital, Yonsei University College of Medicine, Seoul (Korea, Republic of)

    2012-03-15

    The authors present a rare case of papillary carcinoma arising from the pyramidal lobe of the thyroid in a 54-year-old woman, who presented with a right submental palpable mass. An ultrasound evaluation depicted a 3 cm mixed echoic mass from the thyroid cartilage level without a focal lesion in the thyroid gland. Surgical specimens obtained during bilateral thyroidectomy confirmed papillary carcinoma of the pyramidal lobe. To the authors' knowledge, this is the first case report to describe papillary carcinoma arising from the pyramidal lobe of the thyroid gland

  9. Papillary thyroid microcarcinoma in a thyroid pyramidal lobe

    Energy Technology Data Exchange (ETDEWEB)

    Ha, Tae Kwan; Kim, Dong Wook; Park, Ha Kyoung; Jung, Soo Jin [Busan Paik Hospital, Inje University College of Medicine, Busan (Korea, Republic of)

    2014-12-15

    We report an extremely rare case of papillary thyroid microcarcinoma (PTMC) in the thyroid pyramidal lobe (TPL). A 48-year-old woman underwent ultrasound-guided fine-needle aspiration for a small thyroid nodule in the right lobe in local clinic, and it revealed a malignant cytology. On preoperative ultrasonography for tumor staging in our hospital, another small suspiciously malignant hypoechoic nodule was detected in the left TPL. Total thyroidectomy and central nodal dissection were performed. Histopathology confirmed PTMCs in the left TPL and both thyroid lobes. Ultrasonography for TPL should be required for complete evaluation of possible multifocality of thyroid malignancy.

  10. LobeFinder: A Convex Hull-Based Method for Quantitative Boundary Analyses of Lobed Plant Cells.

    Science.gov (United States)

    Wu, Tzu-Ching; Belteton, Samuel A; Pack, Jessica; Szymanski, Daniel B; Umulis, David M

    2016-08-01

    Dicot leaves are composed of a heterogeneous mosaic of jigsaw puzzle piece-shaped pavement cells that vary greatly in size and the complexity of their shape. Given the importance of the epidermis and this particular cell type for leaf expansion, there is a strong need to understand how pavement cells morph from a simple polyhedral shape into highly lobed and interdigitated cells. At present, it is still unclear how and when the patterns of lobing are initiated in pavement cells, and one major technological bottleneck to addressing the problem is the lack of a robust and objective methodology to identify and track lobing events during the transition from simple cell geometry to lobed cells. We developed a convex hull-based algorithm termed LobeFinder to identify lobes, quantify geometric properties, and create a useful graphical output of cell coordinates for further analysis. The algorithm was validated against manually curated images of pavement cells of widely varying sizes and shapes. The ability to objectively count and detect new lobe initiation events provides an improved quantitative framework to analyze mutant phenotypes, detect symmetry-breaking events in time-lapse image data, and quantify the time-dependent correlation between cell shape change and intracellular factors that may play a role in the morphogenesis process. © 2016 American Society of Plant Biologists. All Rights Reserved.

  11. Transcortical mixed aphasia due to cerebral infarction in left inferior frontal lobe and temporo-parietal lobe

    International Nuclear Information System (INIS)

    Maeshima, S.; Matsumoto, T.; Ueyoshi, A.; Toshiro, H.; Sekiguchi, E.; Okita, R.; Yamaga, H.; Ozaki, F.; Moriwaki, H.; Roger, P.

    2002-01-01

    We present a case of transcortical mixed aphasia caused by a cerebral embolism. A 77-year-old right-handed man was admitted to our hospital with speech disturbance and a right hemianopia. His spontaneous speech was remarkably reduced, and object naming, word fluency, comprehension, reading and writing were all severely disturbed. However, repetition of phonemes and sentences and reading aloud were fully preserved. Although magnetic resonance imaging (MRI) showed cerebral infarcts in the left frontal and parieto-occipital lobe which included the inferior frontal gyrus and angular gyrus, single photon emission CT revealed a wider area of low perfusion over the entire left hemisphere except for part of the left perisylvian language areas. The amytal (Wada) test, which was performed via the left internal carotid artery, revealed that the left hemisphere was dominant for language. Hence, it appears that transcortical mixed aphasia may be caused by the isolation of perisylvian speech areas, even if there is a lesion in the inferior frontal gyrus, due to disconnection from surrounding areas. (orig.)

  12. Transcortical mixed aphasia due to cerebral infarction in left inferior frontal lobe and temporo-parietal lobe

    Energy Technology Data Exchange (ETDEWEB)

    Maeshima, S.; Matsumoto, T.; Ueyoshi, A. [Department of Physical Medicine and Rehabilitation, Wakayama Medical University, Wakayama (Japan); Toshiro, H.; Sekiguchi, E.; Okita, R.; Yamaga, H.; Ozaki, F.; Moriwaki, H. [Department of Neurological Surgery, Hidaka General Hospital, Wakayama (Japan); Roger, P. [School of Communication Sciences and Disorders, University of Sydney, Sydney, NSW (Australia)

    2002-02-01

    We present a case of transcortical mixed aphasia caused by a cerebral embolism. A 77-year-old right-handed man was admitted to our hospital with speech disturbance and a right hemianopia. His spontaneous speech was remarkably reduced, and object naming, word fluency, comprehension, reading and writing were all severely disturbed. However, repetition of phonemes and sentences and reading aloud were fully preserved. Although magnetic resonance imaging (MRI) showed cerebral infarcts in the left frontal and parieto-occipital lobe which included the inferior frontal gyrus and angular gyrus, single photon emission CT revealed a wider area of low perfusion over the entire left hemisphere except for part of the left perisylvian language areas. The amytal (Wada) test, which was performed via the left internal carotid artery, revealed that the left hemisphere was dominant for language. Hence, it appears that transcortical mixed aphasia may be caused by the isolation of perisylvian speech areas, even if there is a lesion in the inferior frontal gyrus, due to disconnection from surrounding areas. (orig.)

  13. Cognitive impairments in patients with intractable temporal lobe epilepsy

    Directory of Open Access Journals (Sweden)

    Mahgol Tavakoli

    2011-01-01

    Conclusions: These findings indicated that WMS-III and WAIS-R can differentiate patients with refractory temporal lobe epilepsy from normal subjects. However, the obtained cognitive profile could not differentiate between the right and the left TLE.

  14. Distinct frontal lobe morphology in girls and boys with ADHD

    Directory of Open Access Journals (Sweden)

    Benjamin Dirlikov

    2015-01-01

    Conclusions: These results elucidate sex-based differences in cortical morphology of functional subdivisions of the frontal lobe and provide additional evidence of associations among SA and symptom severity in children with ADHD.

  15. [Morphological abnormalities of limbic lobe structures in partial temporal lobe epilepsy].

    Science.gov (United States)

    Krémer, S; Braun, M; Kahane, P; Teil, E; Pasquier, B; Benabid, A L; Le Bas, J

    2001-04-01

    To evaluate lesions of the different structures of the Papez circuit in association with hippocampal sclerosis. and methods. 13 patients (32.1+/-8.2 y.o.) suffering from partial, temporal lobe, drug-resistant epilepsy and 20 normal volunteers (31.8+/-7.7 y.o.) were evaluated by MRI on a 1.5 T scanner (Philips): axial T1w 3D Gradient Echo acquisitions, thickness: 1.5mm. Hippocampus and cingulate gyrus volume were calculated after semi-automated segmentation of intrasulcal gray matter using the "Surgiscope Scopeplan" Elekta((R)). The thickness of the posterior column of the fornix and the thickness of the mamillary bodies were also measured. We found 10 cases of ipsolateral hippocampal sclerosis, 6 cases of ipsolateral atrophy of the mamillary body and 4 cases of ipsolateral atrophy of the fornix. We did not find any atrophy of the cingulate gyrus. Hippocampal sclerosis can be associated with lesions of limbic lobe structures (fornix and mamillary body), excluding the cingulate gyrus.

  16. Surgical techniques for the treatment of temporal lobe epilepsy.

    Science.gov (United States)

    Al-Otaibi, Faisal; Baeesa, Saleh S; Parrent, Andrew G; Girvin, John P; Steven, David

    2012-01-01

    Temporal lobe epilepsy (TLE) is the most common form of medically intractable epilepsy. Advances in electrophysiology and neuroimaging have led to a more precise localization of the epileptogenic zone within the temporal lobe. Resective surgery is the most effective treatment for TLE. Despite the variability in surgical techniques and in the extent of resection, the overall outcomes of different TLE surgeries are similar. Here, we review different surgical interventions for the management of TLE.

  17. Accessory hepatic lobe simulating a left hemidiaphragmatic tumor

    International Nuclear Information System (INIS)

    Kuroiwa, Toshiro; Hirata, Hitoshi; Iwashita, Akinori; Yasumori, Kotaro; Mogami, Hiroshi; Teraoka, Hiroaki

    1984-01-01

    A 72-year-old woman with a 20-year history of neuralgia was confirmed at surgery to have a tumor in the left hemidiaphragmatic region which was connected with the left lobe of the liver. Reassessment of radiological diagnosis after surgery revealed that hepatobiliary scintigraphy and computed tomography using left anterior oblique scanning are useful in differentiating the accessory hepatic lobe of the liver from a tumor and in confirming the diagnosis, respectively. (Namekawa, K.)

  18. Neuroimaging observations linking neurocysticercosis and mesial temporal lobe epilepsy with hippocampal sclerosis.

    Science.gov (United States)

    Bianchin, Marino M; Velasco, Tonicarlo R; Wichert-Ana, Lauro; Araújo, David; Alexandre, Veriano; Scornavacca, Francisco; Escorsi-Rosset, Sara R; dos Santos, Antonio Carlos; Carlotti, Carlos G; Takayanagui, Osvaldo M; Sakamoto, Américo C

    2015-10-01

    To test if chronic calcificed neurocysticercosis (cNCC) and hippocampal sclerosis occur more often than by chance ipsilateral to the same brain hemisphere or brain region in mesial temporal lobe epilepsy associated with hippocampal sclerosis (MTLE-HS) plus neurocysticercosis. This proof-of-concept would provide important evidence of a direct pathogenic relationship between neurocysticercosis and MTLE-HS. A cohort of 290 consecutive MTLE-HS surgical patients was studied. A test of proportions was used to analyze if the proportion of patients with a single cNCC lesion matching the same brain hemisphere or region of hippocampal sclerosis was significantly greater than 50%, as expected by the chance. Neuroimaging findings of cNCC were observed in 112 (38.6%) of 290 MTLE-HS patients and a single cNCC lesion occurred in 58 (51.8%) of them. There were no differences in main basal clinical characteristics of MTLE-HS patients with single or multiple cNCC lesions. In patients with single cNCC lesions, the lesion matched the side in which hippocampal sclerosis was observed in 43 (74.1%) patients, a proportion significantly greater than that expected to occur by chance (p=0.008). Neurocysticercosis in temporal lobe was ipsilateral to hippocampal sclerosis in 85.0% of patients and accounted mostly for this result. This work is a proof-of-concept that the association of neurocysticercosis and MTLE-HS cannot be explained exclusively by patients sharing common biological or socio-economic predisposing variables. Instead, our results suggest the involvement of more direct pathogenic mechanisms like regional inflammation, repetitive seizures or both. Neurocysticercosis within temporal lobes was particularly related with ipsilateral hippocampal sclerosis in MTLE-HS, a finding adding new contributions for understanding MTLE-HS plus cNCC or perhaps to other forms of dual pathology in MTLE-HS. Copyright © 2015 Elsevier B.V. All rights reserved.

  19. Transient simulation in interior flow field of lobe pump

    International Nuclear Information System (INIS)

    Li, Y B; Sang, X H; Shen, H; Jia, K; Meng, Q W

    2013-01-01

    The subject of this paper is mainly focused on the development and control of the double folium and trifolium lobe pump profiles by using the principle of involute engagement and use CAD to get an accurate involute profile. We use the standard k-ε turbulence model and PISO algorithm based on CFD software FLUENT. The dynamic mesh and UDF technology is introduced to simulate the interior flow field inside a lobe pump, and the variation of interior flow field under the condition of the lobe rotating is analyzed. We also analyse the influence produced by the difference in lobes, and then reveal which lobe is best. The results show that dynamic variation of the interior flow field is easily obtained by dynamic mesh technology and the distribution of its pressure and velocity. Because of the small gaps existing between the rotors and pump case, the higher pressure area will flow into the lower area though the small gaps which cause the working area keep with higher pressure all the time. Both of the double folium and trifolium are existing the vortex during the rotting time and its position, size and shape changes all the time. The vortexes even disappear in a circle period and there are more vortexes in double folium lobe pump. The velocity and pressure pulsation of trifolium pump are lower than that of the double folium

  20. Famous People Knowledge and the Right and Left Temporal Lobes

    Science.gov (United States)

    Snowden, Julie S.; Thompson, Jennifer C.; Neary, David

    2012-01-01

    It is generally accepted that the anterior temporal lobes support knowledge of famous people. The specific roles of the right and left temporal lobe remain a subject of debate, with some studies suggesting differential roles based on modality (visual versus verbal information) and others category (person knowledge versus general semantics). The present study re-examined performance of semantic dementia patients with predominantly right and predominantly left temporal lobe atrophy on famous face, famous name and general semantic tasks, with the specific aim of testing the hypothesis that the right temporal lobe has a privileged role for person knowledge and the left temporal lobe for general semantic knowledge. Comparisons of performance rankings across tasks showed no evidence to support this hypothesis. By contrast, there was robust evidence from naming, identification and familiarity measures for modality effects: right-sided atrophy being associated with relatively greater impairment for faces and visual tasks and left-sided atrophy for names and verbal tasks. A double dissociation in test scores in two patients reinforced these findings. The data present a challenge for the influential ‘semantic hub’ model, which views the anterior temporal lobes as an area of convergence in which semantic information is represented in amodal form. PMID:22207421

  1. Bicavitary effusion secondary to liver lobe torsion in a dog

    Directory of Open Access Journals (Sweden)

    Khan Z

    2016-04-01

    Full Text Available Zaheda Khan,1 Kathryn Gates,2 Stephen A Simpson,31Emergency and Critical Care, Animal Specialty and Emergency Center, Los Angeles, CA, 2Emergency and Critical Care, Advanced Critical Care, Emergency and Specialty Services, Culver City, CA 3Emergency and Critical Care, Southern California Veterinary Specialty Hospital, Irvine, CA, USA Abstract: We described the diagnosis and successful treatment of pleural and peritoneal effusion secondary to liver lobe torsion in a dog. A 12-year-old female spayed Borzoi dog was referred for heart failure. Emergency room thoracic and abdominal ultrasound showed a large volume of pleural effusion with mild peritoneal effusion and an abdominal mass. Pleural fluid analysis classified the effusion as exudative. A complete ultrasound revealed mild peritoneal effusion and decreased blood flow to the right liver lobe. Other causes of bicavitary effusion were ruled out based on blood work, ultrasound, echocardiogram, and computed tomography. The patient was taken to surgery and diagnosed with caudate liver lobe torsion and had a liver lobectomy. At the 2-week postoperative recheck, the patient was doing well and there was complete resolution of the pleural effusion. Liver lobe torsion is a rare occurrence in dogs and can be difficult to diagnose. Clinical signs are nonspecific for liver lobe torsion and patients may present in respiratory distress with significant pleural fluid accumulation. When assessing patients with pleural and peritoneal effusion, liver lobe torsion should be considered as a differential diagnosis.Keywords: pleural effusion, peritoneal effusion, hepatic torsion

  2. Medical image of the week: right middle lobe syndrome

    Directory of Open Access Journals (Sweden)

    Cristan EA

    2016-05-01

    Full Text Available No abstract available. Article truncated at 150 words. A 73 year-old woman, a lifetime non-smoker, presented to the pulmonary clinic with chronic dyspnea on exertion and cough. Physical exam was unremarkable and pulmonary function testing showed normal spirometry. A chest radiograph revealed calcified mediastinal adenopathy and increased density in the right middle lobe region (Figure 1. A computed tomography scan of the chest revealed significant narrowing of the right middle lobe bronchus with partial atelectasis and prominent calcified mediastinal lymphadenopathy (Figure 2. Bronchoscopy showed no endobronchial lesions but there was evidence of extrinsic compression surrounding the right middle lobe orifice. An endobronchial biopsy revealed noncaseating granulomas. Bronchoscopy cultures and cytology were negative and this was presumed to be from a previous infection with histoplasmosis given the patient’s long-term residence in an endemic area. Given chronic narrowing of right middle lobe bronchus with persistent atelectasis of the right middle lobe, the patient was diagnosed with right middle lobe syndrome. ...

  3. The UK contribution to the CEC PACOMA Project: far-field modelling of radioactive waste disposal in clay

    International Nuclear Information System (INIS)

    Winters, K.H.; Jackson, C.P.; Clark, C.M.

    1990-06-01

    PACOMA (Performance Assessment of Confinement for Medium-active and Alpha-bearing wastes) is a multinational project supported as part of the Commission of the European Community's R and D programme on radioactive waste management and storage. The aim of the project is to assess the radiological impact of deep geological disposal of intermediate level waste in three different types of geological formation: clay, granite and salt. The contribution of AEA Technology is a study of the groundwater flow and radionuclide migration in the far field. This report describes the far-field modelling. The three-stratum model used in previous hydrogeological studies of the Harwell region is used as a basis for the far-field two-dimensional section through the chalk, clay and Corallian strata underlying Harwell. Each of the three layers is represented as a continuous porous medium with an assumed best-estimate value of permeability, and the groundwater flow is predicted by solving the Darcy equations over the complete section using the NAMMU finite-element code. Two-dimensional transport equations describing the migration of radionuclides in the groundwater are solved, also using NAMMU. The fluxes of radionuclides normal to the surface of the water table are calculated as a function of space and time. The most significant result of the calculations of radionuclide transport through the geosphere is the prediction of multiple pathways for radionuclide movement in the geological strata, and hence multiple release points into the biosphere. Particular attention is paid in the study to the performance and appropriation of the numerical methods and the physical models used for the far-field calculations. (author)

  4. Regulation of spindle orientation and neural stem cell fate in the Drosophila optic lobe

    Directory of Open Access Journals (Sweden)

    Brand Andrea H

    2007-01-01

    Full Text Available Abstract Background The choice of a stem cell to divide symmetrically or asymmetrically has profound consequences for development and disease. Unregulated symmetric division promotes tumor formation, whereas inappropriate asymmetric division affects organ morphogenesis. Despite its importance, little is known about how spindle positioning is regulated. In some tissues cell fate appears to dictate the type of cell division, whereas in other tissues it is thought that stochastic variation in spindle position dictates subsequent sibling cell fate. Results Here we investigate the relationship between neural progenitor identity and spindle positioning in the Drosophila optic lobe. We use molecular markers and live imaging to show that there are two populations of progenitors in the optic lobe: symmetrically dividing neuroepithelial cells and asymmetrically dividing neuroblasts. We use genetically marked single cell clones to show that neuroepithelial cells give rise to neuroblasts. To determine if a change in spindle orientation can trigger a neuroepithelial to neuroblast transition, we force neuroepithelial cells to divide along their apical/basal axis by misexpressing Inscuteable. We find that this does not induce neuroblasts, nor does it promote premature neuronal differentiation. Conclusion We show that symmetrically dividing neuroepithelial cells give rise to asymmetrically dividing neuroblasts in the optic lobe, and that regulation of spindle orientation and division symmetry is a consequence of cell type specification, rather than a mechanism for generating cell type diversity.

  5. Simulation of Far-Field Superresolution Fluorescence Imaging with Two-Color One-Photon Excitation of Reversible Photoactivatable Protein

    International Nuclear Information System (INIS)

    Wang Chen; Qiao Ling-Ling; Mao Zheng-Le

    2011-01-01

    We propose to achieve far-field super-resolution imaging by using offset two-color one-photon (2C1P) excitation of reversible photoactivatable fluorescence proteins. Due to the distinctive photoswitching performance of the proteins, such as dronpa, the fluorescence emission will only come from the overlapped region of activation beam and excitation beam. The analysis solution of rate equation shows that the resolution of offset 2C1P microscope is 'engineered' by laser power of excitation and activation beams and the power ratio between them. Superior lateral and transverse resolution is theoretically demonstrated compared with conventional fluorescence scanning microscopy. (fundamental areas of phenomenology(including applications))

  6. Benchmark Modeling of the Near-Field and Far-Field Wave Effects of Wave Energy Arrays

    Energy Technology Data Exchange (ETDEWEB)

    Rhinefrank, Kenneth E; Haller, Merrick C; Ozkan-Haller, H Tuba

    2013-01-26

    This project is an industry-led partnership between Columbia Power Technologies and Oregon State University that will perform benchmark laboratory experiments and numerical modeling of the near-field and far-field impacts of wave scattering from an array of wave energy devices. These benchmark experimental observations will help to fill a gaping hole in our present knowledge of the near-field effects of multiple, floating wave energy converters and are a critical requirement for estimating the potential far-field environmental effects of wave energy arrays. The experiments will be performed at the Hinsdale Wave Research Laboratory (Oregon State University) and will utilize an array of newly developed Buoys' that are realistic, lab-scale floating power converters. The array of Buoys will be subjected to realistic, directional wave forcing (1:33 scale) that will approximate the expected conditions (waves and water depths) to be found off the Central Oregon Coast. Experimental observations will include comprehensive in-situ wave and current measurements as well as a suite of novel optical measurements. These new optical capabilities will include imaging of the 3D wave scattering using a binocular stereo camera system, as well as 3D device motion tracking using a newly acquired LED system. These observing systems will capture the 3D motion history of individual Buoys as well as resolve the 3D scattered wave field; thus resolving the constructive and destructive wave interference patterns produced by the array at high resolution. These data combined with the device motion tracking will provide necessary information for array design in order to balance array performance with the mitigation of far-field impacts. As a benchmark data set, these data will be an important resource for testing of models for wave/buoy interactions, buoy performance, and far-field effects on wave and current patterns due to the presence of arrays. Under the proposed project we will initiate

  7. Dual Spacecraft Observations of Lobe Magnetic Field Perturbations Before, During and after Plasmoid Release

    Science.gov (United States)

    Slavin, J. A.; Hesse, M.; Owen, C. J.; Taguchi, S.; Fairfield, D. H.; Lepping, R. P.; Kokubun, S.; Mukai, T.; Lui, A. T. Y.; Anderson, R. R.

    1999-01-01

    This study examines a unique data set returned by IMP8 and Geotail on January 29, 1995 during a substorm which resulted in the ejection of a plasmoid. The two spacecraft (s/c) were situated in the north lobe of the tail and both observed a traveling compression region (TCR). From single s/c observations only the length of the plasmoid in X and an estimate of its height in Z can be determined. However, we show that dual s/c measurements of TCRs can be used to model all three dimensions of the underlying plasmoid and to estimate of its rate of expansion or contraction. For this event plasmoid dimensions of Delta(X) approximates 18, Delta(Y) approximates 30, and Delta(Z) approximates 10 R(sub e) are inferred from the IMP8 and Geotail lobe magnetic field measurements. The earthward end of the plasmoid was inferred to be near the mean location of the near-earth neutral line, X approximates -26 R(sub e). Its center was underneath IMP 8 at X approximates -34 R(sub e) and its tailward end appeared to be near X approximates -44 R(sub e). Furthermore, a factor of approximately 2 increase in the amplitude of the TCR occurred in the 1.5 min it took to move from IMP 8 to Geotail. Modeled using conservation of the magnetic flux, this increase in lobe compression implies that the underlying plasmoid was expanding at a rate of approximately 140 km/s. Such an expansion is comparable to recently reported V(sub y) speeds in "young" plasmoids in this region of the tail. Finally, the Geotail measurements indicate that a reconfiguration of the lobe magnetic field closely followed the ejection of the plasmoid which moved magnetic flux tubes into the wake behind the plasmoid where they would convect into the near-earth neutral line and reconnect.

  8. A CLINICORADIOLOGICAL STUDY OF MIDDLE LOBE SYNDROME DUE TO TUBERCULOSIS

    Directory of Open Access Journals (Sweden)

    Saurabh Karmakar

    2016-09-01

    Full Text Available BACKGROUND Although pulmonary tuberculosis is a common disease in India, tuberculosis of right middle lobe is infrequent. Tuberculosis of the right middle lobe leading to chronic collapse is a cause of Right Middle Lobe syndrome. METHODS The patients attended Pulmonary Medicine Outdoor at Era’s Lucknow Medical College, Lucknow from April 2015 to March 2016. The purpose of this study is to describe the clinicoradiological features of patients of middle lobe syndrome due to tuberculosis. All patients presented with cough with or without expectoration, fever, chest pain, haemoptysis and constitutional symptoms like loss of appetite and weight. Chest X-ray PA view revealed ill-defined opacity abutting the right cardiac border. HRCT thorax was done in each case. The diagnosis of tuberculous aetiology was based on (1 History of chronic cough and fever, not responding to antibiotic therapy and constitutional symptoms, (2 A positive tuberculin test using 2 TU of PPD RT 23 and (3 Detection of acid fast bacilli by direct smear or Mycobacterium tuberculosis by polymerase chain reaction in bronchoalveolar lavage. RESULTS Out of 10 patients, 4 (40% were males and 6 (60% were females. The mean ages of the males were 55.8 years and females were 60.8 years and overall mean age was 59 years. Most of the patients were females and belonged to the middle age and old age group. ATT was started in all the patients. CONCLUSIONS Right middle lobe syndrome predominantly affects the older population and the female gender. Although tuberculosis is a common disease in India, Middle Lobe Syndrome is a very rare presentation of the disease. Due to non-specific symptoms and usually normal chest X-ray PA view in Right Middle Lobe Syndrome, we should keep a high index of suspicion to diagnose the condition.

  9. An optical super-microscope for far-field, real-time imaging beyond the diffraction limit.

    Science.gov (United States)

    Wong, Alex M H; Eleftheriades, George V

    2013-01-01

    Optical microscopy suffers from a fundamental resolution limitation arising from the diffractive nature of light. While current solutions to sub-diffraction optical microscopy involve combinations of near-field, non-linear and fine scanning operations, we hereby propose and demonstrate the optical super-microscope (OSM) - a superoscillation-based linear imaging system with far-field working and observation distances - which can image an object in real-time and with sub-diffraction resolution. With our proof-of-principle prototype we report a point spread function with a spot size clearly reduced from the diffraction limit, and demonstrate corresponding improvements in two-point resolution experiments. Harnessing a new understanding of superoscillations, based on antenna array theory, our OSM achieves far-field, sub-diffraction optical imaging of an object without the need for fine scanning, data post-processing or object pre-treatment. Hence the OSM can be used in a wide variety of imaging applications beyond the diffraction limit, including real-time imaging of moving objects.

  10. Frontal lobe atrophy of the brain in schizophrenia

    International Nuclear Information System (INIS)

    Hara, Tomio

    1981-01-01

    Reported here are the CT findings on cerebral atrophic lesion chiefly developed in the frontal lobe in schizophrenics with unusual organic encephalopathy. Encephalopathy was recognized in 84 (73%) of 115 schizophrenics and 13 (33%) of 40 neurotics. In an attempt to exclude the effects of aging on encephalopathy, the ages at CT and at the development of disease, the number of morbid years, subtypical schizophrenia and relation between the clinical severity and the atrophic condition were comparatively studied. As a result, cerebral atrophy tended to increase along with aging, but the findings differed in that atrophia classified by age covered the entire brain in general, whereas atrophia in schizophrenics was found in the frontal lobe. In particular, because of the fact that clinical severity and atrophia in the frontal lobe are high correlated and that severe atrophia is recognized even in young people, schizophrenia and atrophia in the frontal lobe are considered to be closely related to each other. It is therefore suggested that the CT findings are useful to clinicians for finding appropriate methods to deal with the prognosis of schizophrenics in their daily diagnosis and for the therapeutic prevention of encephalatrophy by stimulating the frontal lobe, thereby delaying mental deterioration. (author)

  11. Neuropsychological deficits in temporal lobe epilepsy: A comprehensive review

    Directory of Open Access Journals (Sweden)

    Fengqing Zhao

    2014-01-01

    Full Text Available Temporal lobe epilepsy (TLE is the most prevalent form of complex partial seizures with temporal lobe origin of electrical abnormality. Studies have shown that recurrent seizures affect all aspects of cognitive functioning, including memory, language, praxis, executive functions, and social judgment, among several others. In this article, we will review these cognitive impairments along with their neuropathological correlates in a comprehensive manner. We will see that neuropsychological deficits are prevalent in TLE. Much of the effort has been laid on memory due to the notion that temporal lobe brain structures involved in TLE play a central role in consolidating information into memory. It seems that damage to the mesial structure of the temporal lobe, particularly the amygdale and hippocampus, has the main role in these memory difficulties and the neurobiological plausibility of the role of the temporal lobe in different aspects of memory. Here, we will cover the sub-domains of working memory and episodic memory deficits. This is we will further proceed to evaluate the evidences of executive function deficits in TLE and will see that set-shifting among other EFs is specifically affected in TLE as is social cognition. Finally, critical components of language related deficits are also found in the form of word-finding difficulties. To conclude, TLE affects several of cognitive function domains, but the etiopathogenesis of all these dysfunctions remain elusive. Further well-designed studies are needed for a better understanding of these disorders.

  12. Giant lipoma arising from deep lobe of the parotid gland

    Directory of Open Access Journals (Sweden)

    Hsu Ying-Che

    2006-06-01

    Full Text Available Abstract Background Lipomas are common benign soft tissue neoplasms but they are found very rarely in the deep lobe of parotid gland. Surgical intervention in these tumors is challenging because of the proximity of the facial nerve, and thus knowledge of the anatomy and meticulous surgical technique are essential. Case presentation A 71-year-old female presented with a large asymptomatic mass, which had occupied the left facial area for over the past fifteen years, and she requested surgical excision for a cosmetically better facial appearance. The computed tomography (CT scan showed a well-defined giant lipoma arising from the left deep parotid gland. The lipoma was successfully enucleated after full exposure and mobilization of the overlying facial nerve branches. The surgical specimen measured 9 × 6 cm in size, and histopathology revealed fibrolipoma. The patient experienced an uneventful recovery, with a satisfying facial contour and intact facial nerve function. Conclusion Giant lipomas involving the deep parotid lobe are extremely rare. The high-resolution CT scan provides an accurate and cost-effective preoperative investigative method. Surgical management of deep lobe lipoma should be performed by experienced surgeons due to the need for meticulous dissection of the facial nerve branches. Superficial parotidectomy before deep lobe lipoma removal may be unnecessary in selected cases because preservation of the superficial lobe may contribute to a better aesthetic and functional result.

  13. Seizure semiology identifies patients with bilateral temporal lobe epilepsy.

    Science.gov (United States)

    Loesch, Anna Mira; Feddersen, Berend; Tezer, F Irsel; Hartl, Elisabeth; Rémi, Jan; Vollmar, Christian; Noachtar, Soheyl

    2015-01-01

    Laterality in temporal lobe epilepsy is usually defined by EEG and imaging results. We investigated whether the analysis of seizure semiology including lateralizing seizure phenomena identifies bilateral independent temporal lobe seizure onset. We investigated the seizure semiology in 17 patients in whom invasive EEG-video-monitoring documented bilateral temporal seizure onset. The results were compared to 20 left and 20 right consecutive temporal lobe epilepsy (TLE) patients who were seizure free after anterior temporal lobe resection. The seizure semiology was analyzed using the semiological seizure classification with particular emphasis on the sequence of seizure phenomena over time and lateralizing seizure phenomena. Statistical analysis included chi-square test or Fisher's exact test. Bitemporal lobe epilepsy patients had more frequently different seizure semiology (100% vs. 40%; psemiology for the identification of bilateral TLE was high (100%) with a specificity of 60%. Lateralizing seizure phenomena had a low sensitivity (59%) but a high specificity (89%). The combination of lateralizing seizure phenomena and different seizure semiology showed a high specificity (94%) but a low sensitivity (59%). The analysis of seizure semiology including lateralizing seizure phenomena adds important clinical information to identify patients with bilateral TLE. Copyright © 2014 Elsevier B.V. All rights reserved.

  14. Case Report: A Rare Case Report of Frontal Lobe Syndrome

    Directory of Open Access Journals (Sweden)

    Morteza Nouri- Khajavi

    2003-04-01

    Full Text Available The frontal lobe syndrome is a permanent personality change disorder with characteristic clinical pictures, which followed by frontal lobes damage. Clinical picture include: Affective instability, recurrent aggressive behavior, impaired social judgment, apathy and undifferentiating or suspiciousness and paranoid ideations. According DSM-IV classification frontal lobe syndrome named personality change due to head trauma on Axis I. Herein we report a case of 46 years-old man, who has developed behavioral disturbances following head trauma, about 10 years ago. Main clinical figures in this case are apathy, avolition and, undifferentiating. Clinical pictures are constant during these 10 years. The diagnostic approach has been based on patient’s problems history which, has taken from his family, mental status examination, Neurological examination, Brain imaging and Neuropsychological assessments which related to frontal lobes function. Because of rarity & neglection due to mysterious function of frontal lobes, and also considering that personality change from previous level is prominent figure of this syndrome and also brain imaging findings, which compatible with clinical findings, with this aim, we have reported this case.

  15. Mapping of potential neurogenic niche in the human temporal lobe

    Directory of Open Access Journals (Sweden)

    Adriano Barreto Nogueira

    2014-10-01

    Full Text Available The subgranular zone (SGZ of the dentate gyrus and the subventricular zone (SVZ are known neurogenic niches in adult mammals. Nonetheless, the existence of neurogenic niches in adult humans is controversial. We hypothesized that mapping neurogenic niches in the human temporal lobe could clarify this issue. Neurogenic niches and neurogenesis were investigated in 28 temporal lobes via immunostaining for nestin and doublecortin (DCX, respectively. Nestin was observed in a continuous layer formed by the SVZ, the subpial zone of the medial temporal lobe and the SGZ, terminating in the subiculum. In the subiculum, remarkable DCX expression was observed through the principal efferent pathway of the hippocampus to the fimbria. A possible explanation for the results is that the SVZ, the subpial zone of the medial temporal lobe and the SGZ form a unit containing neural stem cells that differentiate into neurons in the subiculum. Curiously, the area previously identified as the human rostral migratory stream may in truth be the fornix, which contains axons that originate in the subiculum. This study suggests that neurogenesis may occur in an orchestrated manner in a broad area of the human temporal lobe.

  16. 2.5D far-field diffraction tomography inversion scheme for GPR that takes into account the planar air-soil interface

    DEFF Research Database (Denmark)

    Meincke, Peter

    2001-01-01

    A new 2.5D inversion scheme is derived for fixed-offset ground penetrating radar (GPR) that takes into account the planar air-soil interface. The inversion scheme is based upon the first Born approximation and a far-field approximation of the dyadic Green function for a two-layer medium.......A new 2.5D inversion scheme is derived for fixed-offset ground penetrating radar (GPR) that takes into account the planar air-soil interface. The inversion scheme is based upon the first Born approximation and a far-field approximation of the dyadic Green function for a two-layer medium....

  17. Late bilateral temporal lobe necrosis after conventional radiotherapy. Case report

    Energy Technology Data Exchange (ETDEWEB)

    Hoshi, Michio; Hayashi, Toshiyuki; Kagami, Hiroshi; Murase, Ikurou; Nakatsukasa, Masashi [Saiseikai Utsunomiya Hospital (Japan)

    2003-04-01

    A 63-year-old woman presented with radionecrosis in the bilateral temporal lobes manifesting as dementia about 30 years after undergoing conventional radiotherapy for pituitary adenoma. Computed tomography and magnetic resonance (MR) imaging showed edema and cystic lesions in both temporal lobes. The mass in the left temporal lobe was excised. MR imaging 12 days after surgery showed reduced edema. Her dementia had improved. Radionecrosis usually occurs between several months and a few years after radiotherapy. The incidence of radionecrosis is estimated as 5%, but may be higher with longer follow-up periods. Clinical reports have suggested that larger total doses of radiation are associated with earlier onset of delayed necrosis and the fractional dose is the most significant factor causing cerebral radionecrosis. Radionecrosis can occur long after conventional radiotherapy or stereotactic radiosurgery using a linac-based system or a gamma knife unit. (author)

  18. Unusual ictal foreign language automatisms in temporal lobe epilepsy.

    Science.gov (United States)

    Soe, Naing Ko; Lee, Sang Kun

    2014-12-01

    The distinct brain regions could be specifically involved in different languages and the differences in brain activation depending on the language proficiency and on the age of language acquisition. Speech disturbances are observed in the majority of temporal lobe complex motor seizures. Ictal verbalization had significant lateralization value: 90% of patients with this manifestation had seizure focus in the non-dominant temporal lobe. Although, ictal speech automatisms are usually uttered in the patient's native language, ictal speech foreign language automatisms are unusual presentations of non-dominent temporal lobe epilepsy. The release of isolated foreign language area could be possible depending on the pattern of ictal spreading of non-dominant hemisphere. Most of the case reports in ictal speech foreign language automatisms were men. In this case report, we observed ictal foreign language automatisms in middle age Korean woman.

  19. Usefulness of PET in non-lesional temporal lobe epilepsy

    International Nuclear Information System (INIS)

    Bertuluchi, M.; Arganaraz, R.; Buznick, J.; Pomata, H.

    2011-01-01

    Objective. To evaluate the usefulness of PET in patients with refractory non-lesional temporal lobe epilepsy. Material and methods. We present three patients with features of temporal lobe epilepsy refractory to medication, where high definition MRI was normal. Results. These patients had PET hypometabolism in the temporal areas related to clinical and neurophysiological findings. Two of these patients were implanted with subdural grids to confirm the diagnosis and the third was operated directly based on the findings of PET. Encourage the presentation of the importance in recent years is acquiring the PET. Conclusion. In those patients in clinical neurophysiology and epilepsy with suspected temporal lobe, but in the MRI images show no structural lesions, PET can play an important role defining the diagnosis. (authors)

  20. Volumetric PIV and 2D OH PLIF imaging in the far-field of a low Reynolds number nonpremixed jet flame

    International Nuclear Information System (INIS)

    Gamba, M; Clemens, N T; Ezekoye, O A

    2013-01-01

    Cinematographic stereoscopic PIV with temporal and spatial resolution ranging from 2.6 to 5.5 Kolmogorov scales, which is sufficient to accurately represent most of the dissipation structures, is used in conjunction with Taylor’s frozen flow hypothesis to generate quasi-instantaneous pseudo-volumes of the three-component velocity field in the far-field of a nonpremixed jet flame at the jet exit Reynolds number (Re d ) of 8000. The 3D data enable the computation of the nine components of the velocity gradient tensor and other important kinematic quantities. The volumetric PIV is combined with single-shot simultaneous OH PLIF imaging to mark the instantaneous reaction zone at one plane in the reconstructed volume. The combined datasets enable the investigation of the relationship between the reaction zone and the fully-3D representations of strain, vorticity, kinetic energy dissipation and dilatation, and of the impact of heat release on the structure of turbulence. In this Re d = 8000 flame, it is observed that sheet-like layers of vorticity and dissipation tend to coincide and are aligned with the OH layers, an effect that is believed to be due to the stabilizing effect of heat release on this relatively low Reynolds number jet flame. Furthermore, the spatial organization of the strain field is predominantly driven by the presence of the flame rather than turbulence. Finally, intense dissipation is mostly due to the laminar shear caused by the presence of the flame rather than to the strain generated by vortical structures as typically observed in nonreacting jets. (paper)

  1. Temporal lobe changes following radiation therapy: imaging and proton MR spectroscopic findings

    Energy Technology Data Exchange (ETDEWEB)

    Chong, V.F.H.; Rumpel, H.; Fan, Y.F. [Dept. of Diagnostic Radiology, Singapore General Hospital (Singapore); Mukherji, S.K. [North Carolina Univ., Chapel Hill (United States). Dept. of Radiology

    2001-02-01

    Radiation therapy for nasopharyngeal carcinoma affects the temporal lobes. This paper characterizes proton MR spectroscopic findings of the temporal lobes and correlates them with imaging changes. Single-voxel proton MR spectroscopic examinations were acquired from 13 healthy adult volunteers (25 spectra) and 18 patients (28 spectra). All patients had biopsy-confirmed nasopharyngeal carcinoma and were previously treated with radiation therapy. Six patients (33 %) had a single treatment and12 (67 %) patients had two treatments. Point resolved spectroscopy (PRESS) method was used (TR = 3000 ms, TE = 135 ms) and data processed automatically using the LCModel software package for metabolite quantification. Voxel size and geometry were adapted to the lesion to reduce skull-base lipid contamination. The metabolites were quantitated relative to water signal. For each location, an additional non-water-suppressed reference scan in fully relaxed conditions was performed. The imaging findings were divided into four categories: I, normal; II, edema only; III, contrast-enhancing lesions; and IV, cystic encephalomalacia. The N-acetyl-aspartate levels were reduced in 27 (96 %) spectra. Choline was increased in 3 (11 %), normal in 4 (14 %), and reduced in 21 (75 %) spectra. The creatine level was normal in 8 (29 %) spectra and reduced in 20 (71 %) spectra. Imaging showed 4 (14 %) spectra with category-I imaging findings; 5 (18 %) spectra with category-II findings; 15 (54 %) spectra with category-III findings; and 4 (14 %) spectra with category-IV findings. Magnetic resonance spectroscopy showed reduced N-acetyl-aspartate in radiation-induced temporal lobe changes. Creatine levels were relatively more stable. Choline levels may be increased, normal, or reduced. Imaging findings ranged from normal to contrast-enhancing lesions and cystic encephalomalacia. (orig.)

  2. Semantic dementia and the left and right temporal lobes.

    Science.gov (United States)

    Snowden, Julie S; Harris, Jennifer M; Thompson, Jennifer C; Kobylecki, Christopher; Jones, Matthew; Richardson, Anna M; Neary, David

    2017-08-31

    Semantic dementia, a circumscribed disorder of semantic knowledge, provides a unique model for understanding the neural basis for semantic representation. The study addressed areas of contention: the relative roles of the left and right temporal lobe, the contribution of anterior versus posterior temporal cortex and the status of the anterior temporal lobes as amodal hub. Naming and word comprehension was examined in 41 semantic dementia patients, 31 with left-predominant and 10 right-predominant atrophy. In keeping with expectation, naming and comprehension were significantly poorer in left-predominant patients. Structural magnetic resonance image analysis, using a visual rating scale, showed strong inverse correlations between naming scores and severity of both left anterior and posterior temporal lobe atrophy. By contrast, comprehension performance was more strongly correlated with left posterior temporal atrophy. Analysis of naming errors revealed a correlation between anterior temporal atrophy and associative/functional descriptive responses, implying availability of semantic information. By contrast, 'don't know' responses, indicative of loss of semantic knowledge, were linked to left posterior temporal lobe atrophy. Semantic errors, the hallmark of semantic dementia, were linked to right hemisphere atrophy, especially the right posterior temporal lobe. Matched visual-verbal tasks (famous face and name identification, Pyramids and Palm trees pictures and words, animal knowledge from 3-D models and animal names) administered to nine patients elicited variable correspondence between performance on nonverbal and verbal versions of the task. Marked performance dissociations were demonstrated in some patients: poorer understanding of names/words in left-predominant patients and of faces/pictures/models in right-predominant cases. The findings are compatible with the notion of the anterior temporal lobes as areas of convergence, but are less easily accommodated

  3. Astrocyte uncoupling as a cause of human temporal lobe epilepsy.

    Science.gov (United States)

    Bedner, Peter; Dupper, Alexander; Hüttmann, Kerstin; Müller, Julia; Herde, Michel K; Dublin, Pavel; Deshpande, Tushar; Schramm, Johannes; Häussler, Ute; Haas, Carola A; Henneberger, Christian; Theis, Martin; Steinhäuser, Christian

    2015-05-01

    Glial cells are now recognized as active communication partners in the central nervous system, and this new perspective has rekindled the question of their role in pathology. In the present study we analysed functional properties of astrocytes in hippocampal specimens from patients with mesial temporal lobe epilepsy without (n = 44) and with sclerosis (n = 75) combining patch clamp recording, K(+) concentration analysis, electroencephalography/video-monitoring, and fate mapping analysis. We found that the hippocampus of patients with mesial temporal lobe epilepsy with sclerosis is completely devoid of bona fide astrocytes and gap junction coupling, whereas coupled astrocytes were abundantly present in non-sclerotic specimens. To decide whether these glial changes represent cause or effect of mesial temporal lobe epilepsy with sclerosis, we developed a mouse model that reproduced key features of human mesial temporal lobe epilepsy with sclerosis. In this model, uncoupling impaired K(+) buffering and temporally preceded apoptotic neuronal death and the generation of spontaneous seizures. Uncoupling was induced through intraperitoneal injection of lipopolysaccharide, prevented in Toll-like receptor4 knockout mice and reproduced in situ through acute cytokine or lipopolysaccharide incubation. Fate mapping confirmed that in the course of mesial temporal lobe epilepsy with sclerosis, astrocytes acquire an atypical functional phenotype and lose coupling. These data suggest that astrocyte dysfunction might be a prime cause of mesial temporal lobe epilepsy with sclerosis and identify novel targets for anti-epileptogenic therapeutic intervention. © The Author (2015). Published by Oxford University Press on behalf of the Guarantors of Brain. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  4. Non Linear Analysis on Multi Lobe Journal Bearings

    Science.gov (United States)

    Udaya Bhaskar, S.; Manzoor Hussian, M.; Yousuf Ali, Md.

    2017-08-01

    Multi lobe journal bearings are used in machines which operate at high speeds and high loads. In this paper the multi lobe bearing are analyzed to determine the effect of surface roughness during non linear loading. A non-linear time transient analysis is performed using the fourth order Runge Kutta method. The finite difference method is used to predict the pressure distribution over the bearing surface. The effect of eccentric ratio is studied and the variation of attitude angle is discussed. The journal center trajectories were calculated and plotted.

  5. Transient response of two lobe aerodynamic journal bearing

    Directory of Open Access Journals (Sweden)

    Saurabh Kumar Yadav

    2018-03-01

    Full Text Available The dynamic behavior of a rotor-dynamic system is greatly affected by the performance of aerodynamic bearing and the performance of bearing is characterized by the stiffness and damping coefficients. In the present work, stiffness and damping coefficients of bearing are computed and the performance of the bearing is greatly changed with the change in bearing air film profile. The effect of lobe offset factors on the transient performance of aerodynamic bearing is presented. Bifurcation and Poincare diagrams of two lobe journal bearing have been presented for different offset factors. A bearing designer can judge the bearing performance based on bifurcation diagrams.

  6. Visual field defects after temporal lobe resection for epilepsy

    DEFF Research Database (Denmark)

    Steensberg, Alvilda T; Olsen, Ane Sophie; Litman, Minna

    2018-01-01

    PURPOSE: To determine visual field defects (VFDs) using methods of varying complexity and compare results with subjective symptoms in a population of newly operated temporal lobe epilepsy patients. METHODS: Forty patients were included in the study. Two patients failed to perform VFD testing...... symptoms were only reported by 28% of the patients with a VFD and in two of eight (sensitivity=25%) with a severe VFD. Most patients (86%) considered VFD information mandatory. CONCLUSION: VFD continue to be a frequent adverse event after epilepsy surgery in the medial temporal lobe and may affect...

  7. Visual search tasks: measurement of dynamic visual lobe and relationship with display movement velocity.

    Science.gov (United States)

    Yang, Lin-Dong; Yu, Rui-Feng; Lin, Xue-Lian; Xie, Ya-Qing; Ma, Liang

    2018-02-01

    Visual lobe is a useful tool for predicting visual search performance. Up till now, no study has focused on dynamic visual lobe. This study developed a dynamic visual lobe measurement system (DVLMS) that could effectively map dynamic visual lobe and calculate visual lobe shape indices. The effects of display movement velocity on lobe shape indices were examined under four velocity conditions: 0, 4, 8 and 16 deg/s. In general, with the increase of display movement velocity, visual lobe area and perimeter became smaller, whereas lobe shape roundness, boundary smoothness, symmetry and regularity deteriorated. The elongation index was not affected by velocity. Regression analyses indicated that display movement velocity was important in determining dynamic visual lobe shape indices. Dynamic visual lobe provides another option for better understanding dynamic vision, in addition to dynamic visual acuity. Findings of this study can provide guidelines for analysing and designing dynamic visual tasks. Practitioner Summary: Dynamic visual lobe is important in reflecting the visual ability of searching for a moving target. We developed a dynamic visual lobe measurement system (DVLMS) and examined display movement velocity's effects on lobe shape. Findings revealed that velocity was a key factor affecting dynamic visual lobe shape indices.

  8. Design and operation of an inexpensive far-field laser scanning microscope suitable for use in an undergraduate laboratory course

    Science.gov (United States)

    Pallone, Arthur; Hawk, Eric

    2013-03-01

    Scanning microscope applications span the science disciplines yet their costs limit their use at educational institutions. The basic concepts of scanning microscopy are simple. The microscope probe - whether it produces a photon, electron or ion beam - moves relative to the surface of the sample object. The beam interacts with the sample to produce a detected signal that depends on the desired property to be measured at the probe location on the sample. The microscope transforms the signal for output in a form desired by the user. Undergraduate students can easily construct a far-field laser scanning microscope that illustrates each of these principles from parts available at local electronics and hardware stores and use the microscope to explore properties of devices such as light dependent resistors and biological samples such as leaves. Students can record, analyze and interpret results using a computer and free software.

  9. Spectral and far-field broadening due to stimulated rotational Raman scattering driven by the Nike krypton fluoride laser.

    Science.gov (United States)

    Weaver, James; Lehmberg, Robert; Obenschain, Stephen; Kehne, David; Wolford, Matthew

    2017-11-01

    Stimulated rotational Raman scattering (SRRS) in the ultraviolet region (λ=248  nm) has been observed at the Nike laser over extended propagation paths in air during high power operation. Although this phenomenon is not significant for standard operating configurations at Nike, broadening of the laser spectrum and far-field focal profiles has been observed once the intensity-path length product exceeds a threshold of approximately 1  TW/cm. This paper presents experimental results and a new theoretical evaluation of these effects. The observations suggest that significantly broader spectra can be achieved with modest degradation of the final focal distribution. These results point to a possible path for enhanced laser-target coupling with the reduction of laser-plasma instabilities due to broad laser bandwidth produced by the SRRS.

  10. System studies in PA: Development of process influence diagram (PID) for SFR-1 repository near-field + far-field

    Energy Technology Data Exchange (ETDEWEB)

    Stenhouse, M.J. [Monitor Scientific, LLC, Denver, CO (United States); Miller, W.M.; Chapman, N.A. [QuantiSci Ltd., Melton Mowbray (United Kingdom)

    2001-05-01

    Scenario development is a key component of the performance assessment (PA) process for radioactive waste disposal, the primary objective being to ensure that all relevant factors associated with the future evolution of the repository system are properly considered in PA. As part of scenario development, a list of features, events and processes (FEPs) are identified and assembled, representing the Process System, with interactions/influences between FEPs incorporated in a Process Influence Diagram (PID). This report documents the technical work conducted between 1997 and the end of 1999 under the Systems Studies Project. The overall objective of this project has been the construction of a PID for the SFR-1 repository (final repository for reactor waste), this PID being the first stage in the identification of scenarios to describe future evolution of this repository. The PIDs discussed in this report have been created using two software applications: existing commercial software (Business Modeller, Infotool AB. Stockholm, Sweden) and, more recently, a newly developed software tool SPARTA (Enviros QuantiSci, Henley, U.K.). Although the focus of this report is on the application of SPARTA to PID development, it is important to document the work carried out prior to SPARTA being available, in order to provide a complete record of the entire SFR-1 PID development effort as well as preserving the context of the multi-year project. Following a description of the different disposal sections of the SFR-1 and the various near-field barriers, the sequential development (i.e. near-field of Silo, BMA, BLA, BTF sections; far-field; integrated near-field + far-field) of the PID for SFR-1 repository system using Business Modeller is described. Owing to the complexity of the repository, in terms of number of both different disposal sections (Silo, BLA, BMA, BTF) and barriers associated with each section, the two-dimensional (2D) PID created for SFR-1 using Business Modeller is

  11. System studies in PA: Development of process influence diagram (PID) for SFR-1 repository near-field + far-field

    International Nuclear Information System (INIS)

    Stenhouse, M.J.; Miller, W.M.; Chapman, N.A.

    2001-05-01

    Scenario development is a key component of the performance assessment (PA) process for radioactive waste disposal, the primary objective being to ensure that all relevant factors associated with the future evolution of the repository system are properly considered in PA. As part of scenario development, a list of features, events and processes (FEPs) are identified and assembled, representing the Process System, with interactions/influences between FEPs incorporated in a Process Influence Diagram (PID). This report documents the technical work conducted between 1997 and the end of 1999 under the Systems Studies Project. The overall objective of this project has been the construction of a PID for the SFR-1 repository (final repository for reactor waste), this PID being the first stage in the identification of scenarios to describe future evolution of this repository. The PIDs discussed in this report have been created using two software applications: existing commercial software (Business Modeller, Infotool AB. Stockholm, Sweden) and, more recently, a newly developed software tool SPARTA (Enviros QuantiSci, Henley, U.K.). Although the focus of this report is on the application of SPARTA to PID development, it is important to document the work carried out prior to SPARTA being available, in order to provide a complete record of the entire SFR-1 PID development effort as well as preserving the context of the multi-year project. Following a description of the different disposal sections of the SFR-1 and the various near-field barriers, the sequential development (i.e. near-field of Silo, BMA, BLA, BTF sections; far-field; integrated near-field + far-field) of the PID for SFR-1 repository system using Business Modeller is described. Owing to the complexity of the repository, in terms of number of both different disposal sections (Silo, BLA, BMA, BTF) and barriers associated with each section, the two-dimensional (2D) PID created for SFR-1 using Business Modeller is

  12. Far-Field Tsunami Hazard Assessment Along the Pacific Coast of Mexico by Historical Records and Numerical Simulation

    Science.gov (United States)

    Ortiz-Huerta, Laura G.; Ortiz, Modesto; García-Gastélum, Alejandro

    2018-03-01

    Historical records of the Chile (22 May 1960), Alaska (27 March 1964), and Tohoku (11 March 2011) tsunamis recorded along the Pacific Coast of Mexico are used to investigate the goodness of far-field tsunami modeling using a focal mechanism consisting in a uniform slip distribution on large thrust faults around the Pacific Ocean. The Tohoku 2011 tsunami records recorded by Deep ocean Assessment and Reporting of Tsunami (DART) stations, and at coastal tide stations, were used to validate transoceanic tsunami models applicable to the harbors of Ensenada, Manzanillo, and Acapulco on the coast of Mexico. The amplitude resulting from synthetic tsunamis originated by M w 9.3 earthquakes around the Pacific varies from 1 to 2.5 m, depending on the tsunami origin region and on the directivity due to fault orientation and waveform modification by prominent features of sea bottom relief.

  13. Subnanoradian X-ray phase-contrast imaging using a far-field interferometer of nanometric phase gratings.

    Science.gov (United States)

    Wen, Han; Gomella, Andrew A; Patel, Ajay; Lynch, Susanna K; Morgan, Nicole Y; Anderson, Stasia A; Bennett, Eric E; Xiao, Xianghui; Liu, Chian; Wolfe, Douglas E

    2013-01-01

    Hard X-ray phase-contrast imaging characterizes the electron density distribution in an object without the need for radiation absorption. The power of phase contrast to resolve subtle changes, such as those in soft tissue structures, lies in its ability to detect minute refractive bending of X-rays. Here we report a far-field, two-arm interferometer based on the new nanometric phase gratings, which can detect X-ray refraction with subnanoradian sensitivity, and at the same time overcomes the fundamental limitation of ultra-narrow bandwidths (Δλ/λ~10⁻⁴) of the current, most sensitive methods based on crystal interferometers. On a 1.5% bandwidth synchrotron source, we demonstrate clear visualization of blood vessels in unstained mouse organs in simple projection views, with over an order-of-magnitude higher phase contrast than current near-field grating interferometers.

  14. Portal venous branches to the caudate lobe: number and origin ...

    African Journals Online (AJOL)

    Sixty six livers from adult black Kenyans were obtained during autopsy at the Department of Human Anatomy, University of Nairobi – Kenya. The porta hepatis was carefully dissected and the number and origin of the portal venous branches to the caudate lobe observed and recorded. The collected data was analyzed using ...

  15. The auroral and ionospheric flow signatures of dual lobe reconnection

    Directory of Open Access Journals (Sweden)

    S. M. Imber

    2006-11-01

    Full Text Available We present the first substantial evidence for the occurrence of dual lobe reconnection from ionospheric flows and auroral signatures. The process of dual lobe reconnection refers to an interplanetary magnetic field line reconnecting with lobe field lines in both the northern and southern hemispheres. Two bursts of sunward plasma flow across the noon portion of the open/closed field line boundary (OCB, indicating magnetic flux closure at the dayside, were observed in SuperDARN radar data during a period of strongly northward IMF. The OCB is identified from spacecraft, radar backscatter, and auroral observations. In order for dual lobe reconnection to take place, we estimate that the interplanetary magnetic field clock angle must be within ±10° of zero (North. The total flux crossing the OCB during each burst is small (1.8% and 0.6% of the flux contained within the polar cap for the two flows. A brightening of the noon portion of the northern auroral oval was observed as the clock angle passed through zero, and is thought to be due to enhanced precipitating particle fluxes due to the occurrence of reconnection at two locations along the field line. The number of solar wind protons captured by the flux closure process was estimated to be ~2.5×1030 (4 tonnes by mass, sufficient to populate the cold, dense plasma sheet observed following this interval.

  16. Apolipoprotein E gene and sporadic frontal lobe dementia.

    NARCIS (Netherlands)

    M. Stevens (Martijn); C.M. van Duijn (Cornelia); P. de Knijff (Peter); B.A. Oostra (Ben); M.F. Niermeijer (Martinus); J.C. van Swieten (John); P. Heutink (Peter); C. van Broeckhoven (Christine)

    1997-01-01

    textabstractThe apolipoprotein E gene has been associated with various types of dementia. We studied the connection between the APOE gene and the risk and onset of disease in 34 patients with clinically diagnosed frontal lobe dementia (FLD) derived from a population-based study in the Netherlands. A

  17. Case Report: Frontal lobe tuberculoma: A clinical and imaging ...

    African Journals Online (AJOL)

    Background: Pediatric nervous system tuberculomas are usually infra-tentorial and multiple. A frontal lobe location is rare. Case Details: We report a 10 year-old boy who presented with a chronic headache and episodes of loss of consciousness. He had no signs of primary pulmonary tuberculosis and a diagnosis of frontal ...

  18. High density scalp EEG in frontal lobe epilepsy.

    Science.gov (United States)

    Feyissa, Anteneh M; Britton, Jeffrey W; Van Gompel, Jamie; Lagerlund, Terrance L; So, Elson; Wong-Kisiel, Lilly C; Cascino, Gregory C; Brinkman, Benjamin H; Nelson, Cindy L; Watson, Robert; Worrell, Gregory A

    2017-01-01

    Localization of seizures in frontal lobe epilepsy using the 10-20 system scalp EEG is often challenging because neocortical seizure can spread rapidly, significant muscle artifact, and the suboptimal spatial resolution for seizure generators involving mesial frontal lobe cortex. Our aim in this study was to determine the value of visual interpretation of 76 channel high density EEG (hdEEG) monitoring (10-10 system) in patients with suspected frontal lobe epilepsy, and to evaluate concordance with MRI, subtraction ictal SPECT co-registered to MRI (SISCOM), conventional EEG, and intracranial EEG (iEEG). We performed a retrospective cohort study of 14 consecutive patients who underwent hdEEG monitoring for suspected frontal lobe seizures. The gold standard for localization was considered to be iEEG. Concordance of hdEEG findings with MRI, subtraction ictal SPECT co-registered to MRI (SISCOM), conventional 10-20 EEG, and iEEG as well as correlation of hdEEG localization with surgical outcome were examined. hdEEG localization was concordant with iEEG in 12/14 and was superior to conventional EEG 3/14 (pfrontal epilepsy requiring localization of epileptogenic brain. hdEEG may assist in developing a hypothesis for iEEG monitoring and could potentially augment EEG source localization. Published by Elsevier B.V.

  19. Time Ordering in Frontal Lobe Patients: A Stochastic Model Approach

    Science.gov (United States)

    Magherini, Anna; Saetti, Maria Cristina; Berta, Emilia; Botti, Claudio; Faglioni, Pietro

    2005-01-01

    Frontal lobe patients reproduced a sequence of capital letters or abstract shapes. Immediate and delayed reproduction trials allowed the analysis of short- and long-term memory for time order by means of suitable Markov chain stochastic models. Patients were as proficient as healthy subjects on the immediate reproduction trial, thus showing spared…

  20. Charting the Maturation of the Frontal Lobe: An Electrophysiological Strategy

    Science.gov (United States)

    Segalowitz, S. J.; Davies, Patricia L.

    2004-01-01

    Tracking the functional development of specific regions of the prefrontal cortex in children using event-related potentials (ERPs) is challenging for both technical and conceptual reasons. In this paper we outline our strategy for studying frontal lobe development and present preliminary results from children aged 7-17 years and young adults using…

  1. Multidetector CT evaluation of potential right lobe living donors for ...

    African Journals Online (AJOL)

    Mohamed Saied Abdelgawad

    Multidetector CT evaluation of potential right lobe living donors for liver transplantation. Mohamed Saied Abdelgawad *, Osama L. El-Abd. National Liver Institute, El-Menoufiya University, Shebein El-Koom, Alexandria, Egypt. Received 4 June 2011; accepted 18 June 2011. KEYWORDS. Liver transplantation;. Multidetector ...

  2. Surgical anatomy of the pyramidal lobe and its significance in ...

    African Journals Online (AJOL)

    33:35-37. 10. Harjeet A, Shani D, Jit I, Aggarwal AK. Shape, measurements and weight of the thyroid gland in northwest Indians. Surg Radiol Anat 2004;26:91-95. TABLE III. INVOLVEMENT OF THE PYRAMIDAL LOBE IN VARIOUS THYROID ...

  3. Torsion of right middle lobe after a right upper lobectomy

    Directory of Open Access Journals (Sweden)

    Chen Tung-Ying

    2009-04-01

    Full Text Available Abstract Lobar torsion after lung resection is a quite rare complication. A 50-year-old woman presented typical features on chest radiographs and CT(computed tomography scan of lobar torsion after a right upper lobectomy. After emergency lobectomy of right middle lobe, the patient recovered well and discharged 10 days after the second operation.

  4. Bi‑lobed Perirectal Epidermoid Cyst: An Unusual Cause of ...

    African Journals Online (AJOL)

    tumor markers were unremarkable. Pelvic magnetic resonance imaging (MRI) showed a. 7.5 cm × 5 cm × 6 cm homogenous bi‑lobed cystic mass in the pelvis adherent to the left lateral wall of the rectum and posteriorly to the sacrum with a displacement of the rectum anteriorly and to the right. There was no pelvic sidewall ...

  5. Complications after mesial temporal lobe surgery via inferiortemporal gyrus approach.

    Science.gov (United States)

    Vale, Fernando L; Reintjes, Stephen; Garcia, Hermes G

    2013-06-01

    The purpose of this study was to identify the complications associated with the inferior temporal gyrus approach to anterior mesial temporal lobe resection for temporal lobe epilepsy. This retrospective study examined complications experienced by 483 patients during the 3 months after surgery. All surgeries were performed during 1998-2012 by the senior author (F.L.V.). A total of 13 complications (2.7%) were reported. Complications were 8 delayed subdural hematomas (1.6%), 2 superficial wound infections (0.4%), 1 delayed intracranial hemorrhage (0.2%), 1 small lacunar stroke (0.2%), and 1 transient frontalis nerve palsy (0.2%). Three patients with subdural hematoma (0.6%) required readmission and surgical intervention. One patient (0.2%) with delayed intracranial hemorrhage required readmission to the neuroscience intensive care unit for observation. No deaths or severe neurological impairments were reported. Among the 8 patients with subdural hematoma, 7 were older than 40 years (87.5%); however, this finding was not statistically significant (p = 0.198). The inferior temporal gyrus approach to mesial temporal lobe resection is a safe and effective method for treating temporal lobe epilepsy. Morbidity and mortality rates associated with this procedure are lower than those associated with other neurosurgical procedures. The finding that surgical complications seem to be more common among older patients emphasizes the need for early surgical referral of patients with medically refractory epilepsy.

  6. Bilingualism Alters Children's Frontal Lobe Functioning for Attentional Control

    Science.gov (United States)

    Arredondo, Maria M.; Hu, Xiao-Su; Satterfield, Teresa; Kovelman, Ioulia

    2017-01-01

    Bilingualism is a typical linguistic experience, yet relatively little is known about its impact on children's cognitive and brain development. Theories of bilingualism suggest that early dual-language acquisition can improve children's cognitive abilities, specifically those relying on frontal lobe functioning. While behavioral findings present…

  7. Memory Functions following Surgery for Temporal Lobe Epilepsy in Children

    Science.gov (United States)

    Jambaque, Isabelle; Dellatolas, Georges; Fohlen, Martine; Bulteau, Christine; Watier, Laurence; Dorfmuller, Georg; Chiron, Catherine; Delalande, Olivier

    2007-01-01

    Surgical treatment appears to improve the cognitive prognosis in children undergoing surgery for temporal lobe epilepsy (TLE). The beneficial effects of surgery on memory functions, particularly on material-specific memory, are more difficult to assess because of potentially interacting factors such as age range, intellectual level,…

  8. Brain Regions Underlying Word Finding Difficulties in Temporal Lobe Epilepsy

    Science.gov (United States)

    Trebuchon-Da Fonseca, Agnes; Guedj, Eric; Alario, F-Xavier; Laguitton, Virginie; Mundler, Olivier; Chauvel, Patrick; Liegeois-Chauvel, Catherine

    2009-01-01

    Word finding difficulties are often reported by epileptic patients with seizures originating from the language dominant cerebral hemisphere, for example, in temporal lobe epilepsy. Evidence regarding the brain regions underlying this deficit comes from studies of peri-operative electro-cortical stimulation, as well as post-surgical performance.…

  9. Memory, Metamemory and Their Dissociation in Temporal Lobe Epilepsy

    Science.gov (United States)

    Howard, Charlotte E.; Andres, Pilar; Broks, Paul; Noad, Rupert; Sadler, Martin; Coker, Debbie; Mazzoni, Giuliana

    2010-01-01

    Patients with temporal-lobe epilepsy (TLE) present with memory difficulties. The aim of the current study was to determine to what extent these difficulties could be related to a metamemory impairment. Fifteen patients with TLE and 15 matched healthy controls carried out a paired-associates learning task. Memory recall was measured at intervals of…

  10. Spectral shift between the near-field and far-field optoplasmonic response in gold nanospheres, nanoshells, homo- and hetero-dimers

    Science.gov (United States)

    Cacciola, A.; Iatì, M. A.; Saija, R.; Borghese, F.; Denti, P.; Maragò, O. M.; Gucciardi, P. G.

    2017-07-01

    We investigate the shift between near- and far-field spectral properties in a set of different gold nanostructures using the multipole expansion of the electromagnetic fields. The optical behavior of isolated spheres, gold-silica nanoshells, homo- and hetero-di7mers is studied computationally as a function of the particle size. We show that in isolated nanospheres, both homogeneous and shell-like, the red-shift between near- and far-field peak intensities increases with nanoparticle dimension and has a universal character that can be attributed to the different spectral behavior of the radial component of the enhanced field, dominating in the near-field, with respect to its transverse part, which determines the far-field properties. Calculations on dimers of closely separated nanospheres, instead, highlight that the spectral shift between the maximum field intensity, calculated at the dimer nanocavity center, and the maximum extinction or scattering, computed in the far-field, strongly depends on both the radius of the monomers and the gap distance. The shift can turn from positive (i.e. red-shift) to negative (i.e.blue-shift) depending on the values of the nanostructure parameters. Our results call into question the universality of the energy red-shift, with relevant implications for the optimization of the efficiency in surface enhanced spectroscopies.

  11. A review of sorption of radionuclides under the near- and far-field conditions of an underground radioactive waste repository. Pt. 3

    International Nuclear Information System (INIS)

    Berry, J.A.

    1992-01-01

    This report summarises work funded by the Department of the Environment and UK Nirex Ltd in the area of sorption of radionuclides under the near-field and far-field conditions pertaining to the underground disposal of radioactive waste in the UK that was presented and discussed in Part I. The report also summarises comparable research undertaken overseas (presented in Part II). (author)

  12. Frontal mucocele with intracranial extension causing frontal lobe syndrome.

    Science.gov (United States)

    Weidmayer, Sara

    2015-06-01

    Mucoceles are mucus-containing cysts that form in paranasal sinuses; although mucoceles themselves are benign, this case report highlights the extensive damage they can cause as their expansion may lead to bony erosion and extension of the mucocele into the orbit and cranium; it also presents a rarely reported instance of frontal sinus mucocele leading to frontal lobe syndrome. A thorough discussion and review of mucoceles is included. A 68-year-old white man presented with intermittent diplopia and a pressure sensation in the right eye. He had a history of chronic sinusitis and had had endoscopic sinus surgery 5 years prior. A maxillofacial computed tomography scan revealed a large right frontal sinus mucocele, which had caused erosion along the medial wall of the right orbit and the outer and inner tables of the right frontal sinus. The mucocele had protruded both into the right orbit and intracranially, causing mass effect on the frontal lobe, which led to frontal lobe syndrome. The patient was successfully treated with endoscopic right ethmoidectomy, radial frontal sinusotomy, marsupialization of the mucocele, and transcutaneous irrigation. Paranasal sinus mucoceles may expand and lead to bony erosion and can become very invasive in surrounding structures such as the orbit and cranium. This case not only exhibits a very rare presentation of frontal sinus mucocele with intracranial extension and frontal lobe mass effect causing a frontal lobe syndrome but also demonstrates many of the ocular and visual complications commonly associated with paranasal sinus mucoceles. Early identification and surgical intervention is vital for preventing and reducing morbidity associated with invasive mucoceles, and the patient must be followed regularly to monitor for recurrence.

  13. Computational simulation of multi-strut central lobed injection of hydrogen in a scramjet combustor

    Directory of Open Access Journals (Sweden)

    Gautam Choubey

    2016-09-01

    Full Text Available Multi-strut injection is an approach to increase the overall performance of Scramjet while reducing the risk of thermal choking in a supersonic combustor. Hence computational simulation of Scramjet combustor at Mach 2.5 through multiple central lobed struts (three struts have been presented and discussed in the present research article. The geometry and model used here is slight modification of the DLR (German Aerospace Center scramjet model. Present results show that the presence of three struts injector improves the performance of scramjet combustor as compared to single strut injector. The combustion efficiency is also found to be highest in case of three strut fuel injection system. In order to validate the results, the numerical data for single strut injection is compared with experimental result which is taken from the literature.

  14. Excitatory amino acid transporters EAAT-1 and EAAT-2 in temporal lobe and hippocampus in intractable temporal lobe epilepsy

    DEFF Research Database (Denmark)

    Sarac, Sinan; Afzal, Shoaib; Broholm, Helle

    2009-01-01

    extra-cellular clearance of glutamate by excitatory amino acid transporters (EAAT-1 to EAAT-5). EAAT-1 and EAAT-2 are mainly expressed on astroglial cells for the reuptake of glutamate from the extra-cellular space. We have studied the expression of EAAT-1 and EAAT-2 in the hippocampus and temporal lobe...

  15. Genetic mapping of the LOBED LEAF 1 (ClLL1) gene to a 127.6-kb region in watermelon (Citrullus lanatus L.).

    Science.gov (United States)

    Wei, Chunhua; Chen, Xiner; Wang, Zhongyuan; Liu, Qiyan; Li, Hao; Zhang, Yong; Ma, Jianxiang; Yang, Jianqiang; Zhang, Xian

    2017-01-01

    The lobed leaf character is a unique morphologic trait in crops, featuring many potential advantages for agricultural productivity. Although the majority of watermelon varieties feature lobed leaves, the genetic factors responsible for lobed leaf formation remain elusive. The F2:3 leaf shape segregating population offers the opportunity to study the underlying mechanism of lobed leaf formation in watermelon. Genetic analysis revealed that a single dominant allele (designated ClLL1) controlled the lobed leaf trait. A large-sized F3:4 population derived from F2:3 individuals was used to map ClLL1. A total of 5,966 reliable SNPs and indels were identified genome-wide via a combination of BSA and RNA-seq. Using the validated SNP and indel markers, the location of ClLL1 was narrowed down to a 127.6-kb region between markers W08314 and W07061, containing 23 putative ORFs. Expression analysis via qRT-PCR revealed differential expression patterns (fold-changes above 2-fold or below 0.5-fold) of three ORFs (ORF3, ORF11, and ORF18) between lobed and non-lobed leaf plants. Based on gene annotation and expression analysis, ORF18 (encoding an uncharacterized protein) and ORF22 (encoding a homeobox-leucine zipper-like protein) were considered as most likely candidate genes. Furthermore, sequence analysis revealed no polymorphisms in cDNA sequences of ORF18; however, two notable deletions were identified in ORF22. This study is the first report to map a leaf shape gene in watermelon and will facilitate cloning and functional characterization of ClLL1 in future studies.

  16. Computed tomography in agenesis of the right lobe of the liver

    International Nuclear Information System (INIS)

    Demirci, A.; Diren, H.B.; Selcuk, M.B.

    1990-01-01

    Congenital agenesis of the right lobe of the liver is a rare anomaly. In a case report the diagnosis was made by computed tomography. A retro- or suprahepatic location of the gallbladder and compensatory hypertrophy of the left liver lobe and/or caudata lobe may give support to the diagnosis. Before diagnosing congenital agenesis of the lobe, lobar atrophy due to cirrhosis, cholangiocarcinoma or any other predisposing conditions should be eliminated. (orig.)

  17. File list: His.Neu.20.AllAg.Occipital_Lobe [Chip-atlas[Archive

    Lifescience Database Archive (English)

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  20. File list: ALL.Neu.50.AllAg.Occipital_Lobe [Chip-atlas[Archive

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  1. File list: ALL.Neu.10.AllAg.Occipital_Lobe [Chip-atlas[Archive

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    Lifescience Database Archive (English)

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  5. The Structural Plasticity of White Matter Networks Following Anterior Temporal Lobe Resection

    Science.gov (United States)

    Yogarajah, Mahinda; Focke, Niels K.; Bonelli, Silvia B.; Thompson, Pamela; Vollmar, Christian; McEvoy, Andrew W.; Alexander, Daniel C.; Symms, Mark R.; Koepp, Matthias J.; Duncan, John S.

    2010-01-01

    Anterior temporal lobe resection is an effective treatment for refractory temporal lobe epilepsy. The structural consequences of such surgery in the white matter, and how these relate to language function after surgery remain unknown. We carried out a longitudinal study with diffusion tensor imaging in 26 left and 20 right temporal lobe epilepsy…

  6. Whole-brain MRI phenotyping in dysplasia-related frontal lobe epilepsy.

    Science.gov (United States)

    Hong, Seok-Jun; Bernhardt, Boris C; Schrader, Dewi S; Bernasconi, Neda; Bernasconi, Andrea

    2016-02-16

    To perform whole-brain morphometry in patients with frontal lobe epilepsy and evaluate the utility of group-level patterns for individualized diagnosis and prognosis. We compared MRI-based cortical thickness and folding complexity between 2 frontal lobe epilepsy cohorts with histologically verified focal cortical dysplasia (FCD) (13 type I; 28 type II) and 41 closely matched controls. Pattern learning algorithms evaluated the utility of group-level findings to predict histologic FCD subtype, the side of the seizure focus, and postsurgical seizure outcome in single individuals. Relative to controls, FCD type I displayed multilobar cortical thinning that was most marked in ipsilateral frontal cortices. Conversely, type II showed thickening in temporal and postcentral cortices. Cortical folding also diverged, with increased complexity in prefrontal cortices in type I and decreases in type II. Group-level findings successfully guided automated FCD subtype classification (type I: 100%; type II: 96%), seizure focus lateralization (type I: 92%; type II: 86%), and outcome prediction (type I: 92%; type II: 82%). FCD subtypes relate to diverse whole-brain structural phenotypes. While cortical thickening in type II may indicate delayed pruning, a thin cortex in type I likely results from combined effects of seizure excitotoxicity and the primary malformation. Group-level patterns have a high translational value in guiding individualized diagnostics. © 2016 American Academy of Neurology.

  7. Pulmonary sequestrations of the upper lobe in children: Three presentations

    International Nuclear Information System (INIS)

    Hoeffel, J.C.; Bernard, C.; Didier, F.; Bretagne, M.C.; Gautry, P.; Olive, D.; Prevot, J.; Pernot, C.; Hopital des Enfants, 54 - Vandoeuvre-les-Nancy; Hopital des Enfants, 54 - Vandoeuvre-les-Nancy; Hopital des Enfants, 54 - Vandoeuvre-les-Nancy

    1986-01-01

    Pulmonary sequestrations are congenital abnormalities where nonfunctioning lung tissue receives its vascular supply from the systemic circulation (thoracic or abdominal aorta). It is necessary to establish the diagnosis in childhood when the lesions are uncomplicated. The authors present three cases of sequestration of the apex (2 extralobar and 1 atypical) with the main clinical and radiological features. Sequestrations in the upper lobe are rare, and the usual site is the left lower lobe. Plain X-rays show a dense opacity, sometimes with an air-fluid level: angiography is currently the best mean for definitive diagnosis; however, computed tomography will probably be very useful in the future. Differential diagnosis includes tumours of the superior mediastinum (neurogenic tumours, digestive duplication, bronchogenic cysts, pheochromocytoma and hydatid cysts). (orig.) [de

  8. Short parietal lobe connections of the human and monkey brain

    DEFF Research Database (Denmark)

    Catani, Marco; Robertsson, Naianna; Beyh, Ahmad

    2017-01-01

    The parietal lobe has a unique place in the human brain. Anatomically, it is at the crossroad between the frontal, occipital, and temporal lobes, thus providing a middle ground for multimodal sensory integration. Functionally, it supports higher cognitive functions that are characteristic...... intralobar parietal tracts in twenty-one datasets acquired in vivo from healthy human subjects and eleven ex vivo datasets from five vervet and six macaque monkeys. Three regions of interest (postcentral gyrus, superior parietal lobule and inferior parietal lobule) were used to identify the tracts. Surface...... is a vertical pathway between the superior and inferior parietal lobules. This tract can be divided into an anterior (supramarginal gyrus) and a posterior (angular gyrus) component in both humans and monkey brains. The second prominent intraparietal tract connects the postcentral gyrus to both supramarginal...

  9. Amusia After Right Temporoparietal Lobe Infarction: A Case Report.

    Science.gov (United States)

    Yoo, Hyun-Joon; Moon, Hyun Im; Pyun, Sung-Bom

    2016-10-01

    Which brain regions participate in musical processing remains controversial. During singing and listening a familiar song, it is necessary to retrieve information from the long-term memory. However, the precise mechanism involved in musical processing is unclear. Amusia is impaired perception, understanding, or production of music not attributable to disease of the peripheral auditory pathways or motor system. We report a case of a 36-year-old right-handed man who lost the ability to discriminate or reproduce rhythms after a right temporoparietal lobe infarction. We diagnosed him as an amusic patient using the online version of Montreal Battery of Evaluation of Amusia (MBEA). This case report suggests that amusia could appear after right temporoparietal lobe infarction. Further research is needed to elucidate the dynamic musical processing mechanism and its associated neural structures.

  10. Ictal asystole mimicking seizure deterioration in temporal lobe epilepsy.

    Science.gov (United States)

    Guldiken, Baburhan; Hartl, Elisabeth; Rémi, Jan; Noachtar, Soheyl

    2015-09-01

    We report on a patient with temporal lobe epilepsy, secondary to a left lateral temporal cavernoma, in whom the change in seizure semiology suggested recurrence of secondary generalized seizures. Anticonvulsive medication previously controlled secondary generalized seizures over a period of years but focal seizures continued at a lower rate. Continuous video-EEG monitoring revealed ictal asystole associated with myoclonic syncope and falls during focal seizures arising from the left temporal lobe. After implantation of a cardiac pacemaker, no more falls occurred during the focal seizures. In conclusion, recurrence of seizure-associated falls is typically attributed to recurrence of secondary generalized seizures, however, ictal asystole should be considered in selected epilepsy patients as a differential diagnosis of falls. [Published with video sequence].

  11. Application of own computer program for assessment of brain-fluid index in the medial temporal lobe portions in patients with drug-resistant temporal lobe epilepsy

    International Nuclear Information System (INIS)

    Boguslawska, R.; Skrobowska, E.; Rysz, A.

    2009-01-01

    Background: Epilepsy resistant to pharmacological treatment still remains one of the main problems in contemporary epileptology. The problem most frequently concerns patients with focal epilepsy, with the seizure focus possible to localize. In case of drug-resistant epilepsy, both morphological imaging methods (MR) and manual measurements or volumetry are used. Also functional studies, such as MRS (magnetic resonance spectroscopy), fMRI (functional magnetic resonance), SPECT (single photon emission tomography) and PET (positron emission tomography) are performed. Material/Methods: The study presents application of own computer program based on the method of segmentation of the cerebrospinal fluid (CSF) and the brain tissue. The program calculates automatically the brain-fluin index in the hippocampal region. The material comprises the brain-fluin index results calculated with the presented program in comparison with the method of manual delineation in a group of 50 patients with drug-resistant temporal lobe epilepsy. The program is easy to use, it reads the MR data recorded in DICOM installed on a PC. Results: The brain-fluin index result (expressed as a decimal fraction) is calculated on the basis of 4 consecutive layers examined by MR (evaluating hippocampal structures) performed using SE sequence, and T2-weighted imaging in the frontal plane perpendicular to the long axis of the temporal lobes. The results obtained in epilepsy patients were compared with 24 control subjects. Conclusions: Detailed analysis of the obtained data allowed to conclude that precise hippocampal volume assessment can be obtained by combination of both methods, i.e. manual delineation and automatic calculation of brain-fluin index taking into consideration the total volume of cerebral structures. (authors)

  12. Olfactory Information Processing in the Drosophila Antennal Lobe : Anything Goes?

    OpenAIRE

    Silbering, Ana F.; Okada, Ryuichi; Ito, Kei; Galizia, Cosmas Giovanni

    2008-01-01

    When an animal smells an odor, olfactory sensory neurons generate an activity pattern across olfactory glomeruli of the first sensory neuropil, the insect antennal lobe or the vertebrate olfactory bulb. Here, several networks of local neurons interact with sensory neurons and with output neurons-insect projection neurons, or vertebrate mitral/tufted cells. The extent and form of information processing taking place in these local networks has been subject of controversy. To investigate the ro...

  13. Influence of anxiety on memory performance in temporal lobe epilepsy

    OpenAIRE

    Brown, Franklin C.; Westerveld, Michael; Langfitt, John T.; Hamberger, Marla; Hamid, Hamada; Shinnar, Shlomo; Sperling, Michael R.; Devinsky, Orrin; Barr, William; Tracy, Joseph; Masur, David; Bazil, Carl W.; Spencer, Susan S.

    2013-01-01

    This study examined the degree to which anxiety contributed to inconsistent material-specific memory difficulties among 243 temporal lobe epilepsy patients from the Multisite Epilepsy Study. Visual memory performance on the Rey Complex Figure Test (RCFT) was lower for those with high versus low level of anxiety, but was not found to be related to side of TLE. Verbal memory on the California Verbal Learning Test (CVLT) was significantly lower for left than right TLE patients with low anxiety, ...

  14. Childhood allergic bronchopulmonary aspergillosis presenting as a middle lobe syndrome

    OpenAIRE

    Shah, Ashok; Gera, Kamal; Panjabi, Chandramani

    2016-01-01

    Allergic bronchopulmonary aspergillosis (ABPA) is infrequently documented in children with asthma. Although collapse is not uncommon, middle lobe syndrome (MLS) as a presentation of ABPA is rather a rarity. A 9-year-old female child with asthma presented with increase in intensity of symptoms along with a right midzone patchy consolidation on a chest radiograph. In addition, an ill-defined opacity abutting the right cardiac border with loss of cardiac silhouette was noted. A right lateral vie...

  15. Somnambulism Due to Temporal Lobe Epilepsy - A Case Report

    Directory of Open Access Journals (Sweden)

    Rajesh S

    2004-01-01

    Full Text Available Somnambulism (sleep walking is a disorder of arousal that falls under the parasomnia group. It is more common in children than in adults. (1. The onset of sleep walking in adult life is most unusual and suggests the presence of secondary causes rather than a primary sleep disorder (1. We report a 30-year-old male who presented with repeated episodes of sleep waling possibly due to nocturnal temporal lobe epilepsy.

  16. Frontal Lobe Tuberculoma: A Clinical and Imaging Challenge

    OpenAIRE

    Alemayehu, Tinsae; Ergete, Wondwossen; Abebe, Workeabeba

    2017-01-01

    Background Pediatric nervous system tuberculomas are usually infra-tentorial and multiple. A frontal lobe location is rare. Case Details We report a 10 year-old boy who presented with a chronic headache and episodes of loss of consciousness. He had no signs of primary pulmonary tuberculosis and a diagnosis of frontal tuberculoma was made upon a post-operative biopsy. He improved following treatment with anti-tubercular drugs. Conclusion Tuberculosis should be considered in children with a chr...

  17. Impairments in proverb interpretation following focal frontal lobe lesions☆

    Science.gov (United States)

    Murphy, Patrick; Shallice, Tim; Robinson, Gail; MacPherson, Sarah E.; Turner, Martha; Woollett, Katherine; Bozzali, Marco; Cipolotti, Lisa

    2013-01-01

    The proverb interpretation task (PIT) is often used in clinical settings to evaluate frontal “executive” dysfunction. However, only a relatively small number of studies have investigated the relationship between frontal lobe lesions and performance on the PIT. We compared 52 patients with unselected focal frontal lobe lesions with 52 closely matched healthy controls on a proverb interpretation task. Participants also completed a battery of neuropsychological tests, including a fluid intelligence task (Raven’s Advanced Progressive Matrices). Lesions were firstly analysed according to a standard left/right sub-division. Secondly, a finer-grained analysis compared the performance of patients with medial, left lateral and right lateral lesions with healthy controls. Thirdly, a contrast of specific frontal subgroups compared the performance of patients with medial lesions with patients with lateral frontal lesions. The results showed that patients with left frontal lesions were significantly impaired on the PIT, while in patients with right frontal lesions the impairments approached significance. Medial frontal patients were the only frontal subgroup impaired on the PIT, relative to healthy controls and lateral frontal patients. Interestingly, an error analysis indicated that a significantly higher number of concrete responses were found in the left lateral subgroup compared to healthy controls. We found no correlation between scores on the PIT and on the fluid intelligence task. Overall our results suggest that specific regions of the frontal lobes contribute to the performance on the PIT. PMID:23850600

  18. The secondary lobe as anatomic landmark for different pulmonary diseases

    International Nuclear Information System (INIS)

    Spina, Juan C.; Spina, Juan C. h; Rolnik, Maria C.; Lema, Carlos; Venditi, Julio; Magarinos, Gabriel

    2002-01-01

    The objective of this paper is to present the spectrum of pathological findings in the pulmonary parenchyma, based on the knowledge of the secondary lobe and its components. The evaluation was made using high-resolution computed tomography (HRCT) and compared with the histopathological findings. By definition, the secondary lobe is the small portion of pulmonary tissue separated by septa of connective tissue and supplied by 2-5 or more terminal bronchioles according to their central or peripheral location. Different disorders may become evident as a consequence of : 1) Bronchiolar obstruction (transient or definitive); 2) Intra-alveolar or wall involvement; 3) Involvement of the support tissue; 4) Involvement of the vascular or lymphatic structures. The etiology may be idiopathic, infectious, due to inhalation, neoplastic, allergic, due to collagen diseases, secondary to drug administration and/or post-transplantation. The evaluation of the secondary lobe components, with fine section HRCT, is the dynamic method of choice for the characterisation of pulmonary diseases, and allows to perform earlier and more precise differential diagnoses, when correlated with the clinical findings. The addition of sections during expiration to the routine study is paramount to underscore perfusion disturbances, which may remain undiagnosed during deep inspiration. The goal of this study is to review some of these disorders in which HRCT may be very useful and to correlate our observations with the histopathological findings. (author)

  19. Explicit memory and implicit memory in occipital lobe stroke patients.

    Science.gov (United States)

    Gong, Liang; Wang, JiHua; Feng, Lei; Wang, MeiHong; Li, Xiu; Hu, JiaYun; Wang, Kai

    2015-03-01

    Occipital stroke patients mainly showed cortical blindness and unilateral vision loss; memory is generally reserved. Recent reports from neuroimaging show the occipital lobe may be involved in the processing of implicit memory (IM), especially the perception type of IM processing. In this study, we explored the explicit memory (EM) and IM damage in occipital lobe stroke patients. A total of 25 occipital strokes and 29 years of age, educational level equivalent healthy controls (HCs), evaluated by using immediate recall, delayed recall, recognition for EM tasks, picture identification, and category exemplar generation for IM tasks. There was no significant difference between occipital stroke patients and HCs in EM tasks and category exemplar generation task. In the picture identification task, occipital lobe stroke group score was poorer than HC group, the results were statistically significant, but in the pictures identify rate, occipital stroke patients and normal control group had no significant difference. The occipital stroke patients may have IM damage, primarily damage the perception type of IM priming effects, which was unrelated with their cortical blindness. Copyright © 2015 National Stroke Association. Published by Elsevier Inc. All rights reserved.

  20. Rethinking cognition and behavior in the new classification for childhood epilepsy: Examples from frontal lobe and temporal lobe epilepsies.

    Science.gov (United States)

    Smith, Mary Lou

    2016-11-01

    The new approach to classification of the epilepsies emphasizes the role of dysfunction in networks in defining types of epilepsies. This paper reviews the structural and neuropsychological deficits in two types of childhood epilepsy: frontal lobe and temporal lobe epilepsy. The evidence for and against a pattern of specificity of deficits in executive function and memory associated with these two types of epilepsies is presented. The evidence varies with the methodologies used in the studies, but direct comparison of the two types of epilepsies does not suggest a clear-cut mapping of function onto structure. These findings are discussed in light of the concept of network dysfunction. The evidence supports the conceptualization of epilepsy as a network disease. Implications for future work in the neuropsychology of pediatric epilepsy are suggested. This article is part of a Special Issue entitled "The new approach to classification: Rethinking cognition and behavior in epilepsy". Copyright © 2016 Elsevier Inc. All rights reserved.

  1. USAF Bioenvironmental Noise Data Handbook. Volume 160: KC-10A aircraft, near and far-field noise

    Science.gov (United States)

    Powell, R. G.

    1982-09-01

    The USAF KC-10A aircraft is an advanced tanker/cargo aircraft powered by three CF6-50C2 turbofan engines. This report provides measured and extrapolated data defining the bioacoustic environments produced by this aircraft operating on a concrete runup pad for eight engine/power configurations. Near-field data are reported for one location in a wide variety of physical and psychoacoustic measures: overall and band sound pressure levels, C-weighted and A-weighted sound levels, preferred speech interference levels, perceived noise levels, and limiting times for total daily exposure of personnel with and without standard Air Force ear protectors. Far-field data measured at 15 locations are normalized to standard meteorological conditions and extrapolated from 75-8000 meters to derive sets of equal-value contours for these same seven acoustic measures as functions of angle and distance from the source. Refer to Volume 1 of this handbook, USAF Bioenvironmental Noise Data Handbook, Vol 1: Organization, Content and Application, AMRL-TR-75-50(1) 1975, for discussion of the objective and design of the handbook, the types of data presented, measurement procedures, instrumentation, data processing, definitions of quantities, symbols, equations, applications, limitations, etc.

  2. An Analysis of Mechanical Constraints when Using Superconducting Gravimeters for Far-Field Pre-Seismic Anomaly Detection

    Directory of Open Access Journals (Sweden)

    Shyh-Chin Lan

    2011-01-01

    Full Text Available Pre-seismic gravity anomalies from records obtained at a 1 Hz sampling rate from superconducting gravimeters (SG around East Asia are analyzed. A comparison of gravity anomalies to the source parameters of associated earthquakes shows that the detection of pre-seismic gravity anomalies is constrained by several mechanical conditions of the seismic fault plane. The constraints of the far-field pre-seismic gravity amplitude perturbation were examined and the critical spatial relationship between the SG station and the epicenter precursory signal for detection was determined. The results show that: (1 the pre-seismic amplitude perturbation of gravity is inversely proportional to distance; (2 the transfer path from the epicenter to the SG station that crosses a tectonic boundary has a relatively low pre-seismic gravity anomaly amplitude; (3 the pre-seismic gravity perturbation amplitude is also affected by the attitude between the location of an SG station and the strike of the ruptured fault plane. The removal of typhoon effects and the selection of SG stations within a certain intersection angle to the strike of the fault plane are essential for obtaining reliable pre-seismic gravity anomaly results.

  3. Noise Reduction Method for Quantifying Nanoparticle Light Scattering in Low Magnification Dark-Field Microscope Far-Field Images.

    Science.gov (United States)

    Sun, Dali; Fan, Jia; Liu, Chang; Liu, Yang; Bu, Yang; Lyon, Christopher J; Hu, Ye

    2016-12-20

    Nanoparticles have become a powerful tool for cell imaging and biomolecule, cell and protein interaction studies, but are difficult to rapidly and accurately measure in most assays. Dark-field microscope (DFM) image analysis approaches used to quantify nanoparticles require high-magnification near-field (HN) images that are labor intensive due to a requirement for manual image selection and focal adjustments needed when identifying and capturing new regions of interest. Low-magnification far-field (LF) DFM imagery is technically simpler to perform but cannot be used as an alternate to HN-DFM quantification, since it is highly sensitive to surface artifacts and debris that can easily mask nanoparticle signal. We now describe a new noise reduction approach that markedly reduces LF-DFM image artifacts to allow sensitive and accurate nanoparticle signal quantification from LF-DFM images. We have used this approach to develop a "Dark Scatter Master" (DSM) algorithm for the popular NIH image analysis program ImageJ, which can be readily adapted for use with automated high-throughput assay analyses. This method demonstrated robust performance quantifying nanoparticles in different assay formats, including a novel method that quantified extracellular vesicles in patient blood sample to detect pancreatic cancer cases. Based on these results, we believe our LF-DFM quantification method can markedly decrease the analysis time of most nanoparticle-based assays to impact both basic research and clinical analyses.

  4. Violin f-hole contribution to far-field radiation via patch near-field acoustical holography.

    Science.gov (United States)

    Bissinger, George; Williams, Earl G; Valdivia, Nicolas

    2007-06-01

    The violin radiates either from dual ports (f-holes) or via surface motion of the corpus (top+ribs+back), with no clear delineation between these sources. Combining "patch" near-field acoustical holography over just the f-hole region of a violin with far-field radiativity measurements over a sphere, it was possible to separate f-hole from surface motion contributions to the total radiation of the corpus below 2.6 kHz. A0, the Helmholtz-like lowest cavity resonance, radiated essentially entirely through the f-holes as expected while A1, the first longitudinal cavity mode with a node at the f-holes, had no significant f-hole radiation. The observed A1 radiation comes from an indirect radiation mechanism, induced corpus motion approximately mirroring the cavity pressure profile seen for violinlike bowed string instruments across a wide range of sizes. The first estimates of the fraction of radiation from the f-holes F(f) indicate that some low frequency corpus modes thought to radiate only via surface motion (notably the first corpus bending modes) had significant radiation through the f-holes, in agreement with net volume changes estimated from experimental modal analysis. F(f) generally trended lower with increasing frequency, following corpus mobility decreases. The f-hole directivity (top/back radiativity ratio) was generally higher than whole-violin directivity.

  5. Theoretical and numerical studies of crack initiation and propagation in rock masses under freezing pressure and far-field stress

    Directory of Open Access Journals (Sweden)

    Yongshui Kang

    2014-10-01

    Full Text Available Water-bearing rocks exposed to freezing temperature can be subjected to freeze–thaw cycles leading to crack initiation and propagation, which are the main causes of frost damage to rocks. Based on the Griffith theory of brittle fracture mechanics, the crack initiation criterion, propagation direction, and crack length under freezing pressure and far-field stress are analyzed. Furthermore, a calculation method is proposed for the stress intensity factor (SIF of the crack tip under non-uniformly distributed freezing pressure. The formulae for the crack/fracture propagation direction and length of the wing crack under freezing pressure are obtained, and the mechanism for coalescence of adjacent cracks is investigated. In addition, the necessary conditions for different coalescence modes of cracks are studied. Using the topology theory, a new algorithm for frost crack propagation is proposed, which has the capability to define the crack growth path and identify and update the cracked elements. A model that incorporates multiple cracks is built by ANSYS and then imported into FLAC3D. The SIFs are then calculated using a FISH procedure, and the growth path of the freezing cracks after several calculation steps is demonstrated using the new algorithm. The proposed method can be applied to rocks containing fillings such as detritus and slurry.

  6. Near-field and far-field modeling of scattered surface waves. Application to the apertureless scanning near-field optical microscopy

    International Nuclear Information System (INIS)

    Muller, J.; Parent, G.; Fumeron, S.; Jeandel, G.; Lacroix, D.

    2011-01-01

    The detection of surface waves through scanning near-field optical microscopy (SNOM) is a promising technique for thermal measurements at very small scales. Recent studies have shown that electromagnetic waves, in the vicinity of a scattering structure such as an atomic force microscopy (AFM) tip, can be scattered from near to far-field and thus detected. In the present work, a model based on the finite difference time domain (FDTD) method and the near-field to far-field (NFTFF) transformation for electromagnetic waves propagation is presented. This model has been validated by studying the electromagnetic field of a dipole in vacuum and close to a dielectric substrate. Then simulations for a tetrahedral tip close to an interface are presented and discussed.

  7. Size dependence of silica nanospheres embedded in 385 nm ultraviolet light-emitting diodes on a far-field emission pattern.

    Science.gov (United States)

    Park, Young Jae; Han, Nam; Ryu, Beo Deul; Han, Min; Ko, Kang Bok; Cuong, Tran Viet; Cho, Jaehee; Suh, Eun-Kyung; Hong, Chang-Hee

    2014-10-20

    We demonstrate that the use of silica nanospheres (SNs) with sizes close to the emission wavelength of light-emitting diodes (LEDs) can enhance the light output power and manipulate the far-field emission pattern. Near-ultraviolet (NUV)-LEDs grown on a patterned sapphire substrate embedded with 300 nm SNs show a three times higher light output power than that without SNs, when measured through the top side. For far-field emission measurements, the LEDs embedded with 300 nm SNs show the significant increase of front emission due to the improved crystal quality of epitaxial films as well as the increase of Mie scattering effect of SNs. These experimental results indicate the important role of the size of embedded SNs in enhancing the light output power for NUV-LEDs.

  8. Dynamic statistical parametric mapping for analyzing ictal magnetoencephalographic spikes in patients with intractable frontal lobe epilepsy.

    Science.gov (United States)

    Tanaka, Naoaki; Cole, Andrew J; von Pechmann, Deidre; Wakeman, Daniel G; Hämäläinen, Matti S; Liu, Hesheng; Madsen, Joseph R; Bourgeois, Blaise F; Stufflebeam, Steven M

    2009-08-01

    The purpose of this study is to assess the clinical value of spatiotemporal source analysis for analyzing ictal magnetoencephalography (MEG). Ictal MEG and simultaneous scalp EEG was recorded in five patients with medically intractable frontal lobe epilepsy. Dynamic statistical parametric maps (dSPMs) were calculated at the peak of early ictal spikes for the purpose of estimating the spatiotemporal cortical source distribution. DSPM solutions were mapped onto a cortical surface, which was derived from each patient's MRI. Equivalent current dipoles (ECDs) were calculated using a single-dipole model for comparison with dSPMs. In all patients, dSPMs tended to have a localized activation, consistent with the clinically determined ictal onset zone, whereas most ECDs were considered to be inappropriate sources according to their goodness-of-fit values. Analyzing ictal MEG spikes by using dSPMs may provide useful information in presurgical evaluation of epilepsy.

  9. Storage of Verbal Associations Is Sufficient to Activate the Left Medial Temporal Lobe

    Directory of Open Access Journals (Sweden)

    Andrew R. Mayes

    1999-01-01

    Full Text Available Neuroimaging studies have shown that memory encoding activates the medial temporal lobe (MTL. Many believe that these activations are related to novelty but it remains unproven which is critical - novelty detection or the rich associative encoding it triggers. We examined MTL activation during verbal associative encoding using functional magnetic resonance imaging. First, associative encoding activated left posterior MTL more than single word encoding even though novelty detection was matched, indicating not only that associative encoding activates the MTL particularly strongly, but also that activation does not require novelty detection. Moreover, it remains to be convincingly shown that novelty detection alone does produce such activation. Second, repetitive associative encoding produced less MTL activation than initial associative encoding, indicating that priming of associative information reduces MTL activation. Third, re-encoding familiar associations in a well-established way had a minimal effect on both memory and MTL activation, indicating that MTL activation reflects storage of associations, not merely their initial representation.

  10. Asymmetrical Blood Flow in the Temporal Lobe in the Charles Bonnet Syndrome: Serial Neuroimaging Study

    Directory of Open Access Journals (Sweden)

    N. Adachi

    1994-01-01

    Full Text Available Clinical features and results of neuroimagings of an 86 year old woman with the Charles Bonnet syndrome are reported. She had become completely blind bilaterally due to cataracts and glaucoma. Shortly after an operation for cataracts, she developed visual hallucinations which lasted for 22 years. She had no deterioration of intelligence. Computed tomography (CT and magnetic resonance imaging (MRI showed moderate generalized atrophy, particularly of the temporal lobes. A serial single photon emission computed tomography (SPECT study during visual hallucinations demonstrated hyperperfusion in the left temporal region and the basal ganglia and hypoperfusion in the right temporal region. These findings suggest that asymmetrical blood flow, particularly in the temporal regions, may be correlated with visual hallucination in the Charles Bonnet syndrome.

  11. Plamonics for Biomolecular Sensors and THz Metamaterial Waveguides (Near and Far-Field Interfaces to DNA. Guided Nanostructures from RF to Lightwave: Exploiting the Spectrum)

    Science.gov (United States)

    2014-12-17

    Spectrum for MURI- UCI 14. ABSTRACT 16. SECURITY CLASSIFICATION OF: In THz frequencies, the textured surfaces on a subwavelength scale can support...Near and Far-Field Interfaces to DNA.Guided Nanostructures from RF to Lightwave: Exploiting the Spectrum for MURI- UCI Report Title In THz...interferometer and, more particularly, a Mach-Zehnder Interferometer having a doubly-corrugated spoofed surface plasmon polariton waveguide. ARO & MURI ( UCI

  12. Comparative analysis of MR imaging, Ictal SPECT and EEG in temporal lobe epilepsy: a prospective IAEA multi-center study

    International Nuclear Information System (INIS)

    Zaknun, John J.; Bal, Chandrasekhar; Maes, Alex; Tepmongkol, Supatporn; Vazquez, Silvia; Dupont, Patrick; Dondi, Maurizio

    2008-01-01

    MR imaging, ictal single-photon emission CT (SPECT) and ictal EEG play important roles in the presurgical localization of epileptic foci. This multi-center study was established to investigate whether the complementary role of perfusion SPECT, MRI and EEG for presurgical localization of temporal lobe epilepsy could be confirmed in a prospective setting involving centers from India, Thailand, Italy and Argentina. We studied 74 patients who underwent interictal and ictal EEG, interictal and ictal SPECT and MRI before surgery of the temporal lobe. In all but three patients, histology was reported. The clinical outcome was assessed using Engel's classification. Sensitivity values of all imaging modalities were calculated, and the add-on value of SPECT was assessed. Outcome (Engel's classification) in 74 patients was class I, 89%; class II, 7%; class III, 3%; and IV, 1%. Regarding the localization of seizure origin, sensitivity was 84% for ictal SPECT, 70% for ictal EEG, 86% for MRI, 55% for interictal SPECT and 40% for interictal EEG. Add-on value of ictal SPECT was shown by its ability to correctly localize 17/22 (77%) of the seizure foci missed by ictal EEG and 8/10 (80%) of the seizure foci not detected by MRI. This prospective multi-center trial, involving centers from different parts of the world, confirms that ictal perfusion SPECT is an effective diagnostic modality for correctly identifying seizure origin in temporal lobe epilepsy, providing complementary information to ictal EEG and MRI. (orig.)

  13. On the Seismic Response of Protected and Unprotected Middle-Rise Steel Frames in Far-Field and Near-Field Areas

    Directory of Open Access Journals (Sweden)

    Dora Foti

    2014-01-01

    Full Text Available Several steel moment-resisting framed buildings were seriously damaged during Northridge (1994; Kobe (1995; Kocaeli, Turkey (1999, earthquakes. Indeed, for all these cases, the earthquake source was located under the urban area and most victims were in near-field areas. In fact near-field ground motions show velocity and displacement peaks higher than far-field ones. Therefore, the importance of considering near-field ground motion effects in the seismic design of structures is clear. This study analyzes the seismic response of five-story steel moment-resisting frames subjected to Loma Prieta (1989 earthquake—Gilroy (far-field register and Santa Cruz (near-field register. The design of the frames verifies all the resistance and stability Eurocodes’ requirements and the first mode has been determined from previous shaking-table tests. In the frames two diagonal braces are installed in different positions. Therefore, ten cases with different periods are considered. Also, friction dampers are installed in substitution of the braces. The behaviour of the braced models under the far-field and the near-field records is analysed. The responses of the aforementioned frames equipped with friction dampers and subjected to the same ground motions are discussed. The maximum response of the examined model structures with and without passive dampers is analysed in terms of damage indices, acceleration amplification, base shear, and interstory drifts.

  14. The stratigraphic imprint of a mid-Telychian (Llandovery, Early Silurian glaciation on far-field shallow-water carbonates, Anticosti Island, Eastern Canada

    Directory of Open Access Journals (Sweden)

    François Clayer

    2014-12-01

    Full Text Available The near-field stratigraphic record of the Early Silurian glaciations is well documented in the literature. Data from far-field areas are, however, sparse. One of the best far-field stratigraphic records of these Llandovery glaciations is exposed on Anticosti Island in eastern Canada. Eight shallow-water paleotropical facies are present close to the mid-Telychian Jupiter–Chicotte formational boundary along the south-central coast of Anticosti Island. These can be grouped into three facies associations that include, from bottom to top: a carbonate facies association (FA-1, a mixed siliciclastic and carbonate facies association (FA-2 and an encrinitic facies association (FA-3. These mid- to outer-ramp strata represent deposition mostly from episodic, high-energy storm events as evidenced by their sharp bases, hummocky cross-stratification, large wave ripples, gutter casts and wave-enhanced sediment gravity flow deposits. Superimposed on a long-term regressive trend, one main transgressive–regressive (TR sequence and four meter-scale TR cycles are evident, indicating a multi-order stratigraphic framework developed under the influence of glacio-eustasy. The Jupiter–Chicotte formational boundary, a regional discontinuity surface caused by a forced regression, corresponds to the onset of a far-field mid-Telychian glaciation.

  15. 10kHz TRPIV near-field velocity and far-field noise: experimental results of a Mach 0.6 jet

    Science.gov (United States)

    Kan, Pinqing; Lewalle, Jacques

    2012-11-01

    Last year, we extracted footprints of sources from far-field pressure data of high speed jet. In this paper, we focus on processing 10kHz TR-PIV data in the near-field region. The velocity and pressure data were collected in the jet experiment of Kerwin Low, et al. in 2011. From the PIV snapshots, we extract kinematic indicators, construct their histories over the sequence of snapshots, and select the most promising diagnostics by cross-correlation with far-field pressure. For these indicators, including mass flux, we map out their fluctuations and their downstream propagation. In particular, the phase velocity of fluctuations is compared to the local convective speed. Events with large relative phase velocity are identified, and the corresponding velocity and vorticity fields are mapped out. Our goal is to correlate such events to the far-field footprints of sources. For more info and results related to the experiment, please refer to abstracts by Z.P. Berger and by M.G. Berry at this meeting. This work is supported by Glauser group of Syracuse University, Spectral Energies LLC under AFOSR SBIR grant, and by a Syracuse University Graduate Fellowship. Thanks for partial support from Spectral Energies LLC (under SBIR grant from AFOSR), Syracuse University and the LCS College.

  16. Effect of number of lobes and length-diameter ratio on stability of tilted-lobe hydrodynamic journal bearings at zero load

    Science.gov (United States)

    Schuller, F. T.

    1975-01-01

    Hydrodynamic journal stability tests were conducted with tilted-lobe bearings. The bearings had three, five, and seven lobes and length to diameter (L/D) ratios from 0.2 to 1.0. They were tested in water and MIL-L-7808G oil at 294 K (70 F) at speeds to 5400 rpm with zero load. Stability was not appreciably affected by the number of lobes and decreased with a decrease in L/D ratio. However, a three-tilted-lobe bearing with an offset factor of 0.76 and an L/D of 0.5 was more stable than a three centrally lobed bearing with an offset factor of 0.50 and an L/D of 1.0.

  17. Functional discrepancy between two liver lobes after hemilobe biliary drainage in patients with jaundice and bile duct cancer: an appraisal using (99m)Tc-GSA SPECT/CT fusion imaging.

    Science.gov (United States)

    Sumiyoshi, Tatsuaki; Shima, Yasuo; Okabayashi, Takehiro; Noda, Yoshihiro; Hata, Yasuhiro; Murata, Yoriko; Kozuki, Akihito; Tokumaru, Teppei; Nakamura, Toshio; Uka, Kiminori

    2014-11-01

    To determine the functional discrepancy between the two liver lobes using technetium 99m ((99m)Tc) diethylenetriamine-pentaacetic acid-galactosyl human serum albumin ( GSA diethylenetriamine-pentaacetic acid-galactosyl human serum albumin ) single photon emission computed tomography (SPECT)/computed tomography (CT) fusion imaging following preoperative biliary drainage and portal vein embolization ( PVE portal vein embolization ) in patients with jaundice who have bile duct cancer ( BDC bile duct cancer ). This retrospective study was approved by the institutional review board, with waiver of informed consent. Preoperative (99m)Tc- GSA diethylenetriamine-pentaacetic acid-galactosyl human serum albumin SPECT/CT fusion images from 32 patients with extrahepatic BDC bile duct cancer were retrospectively reviewed. Patients were classified into four groups according to the extent of biliary drainage and presence of a preoperative right PVE portal vein embolization : right lobe drainage group (right drainage), bilateral lobe drainage group (bilateral drainage), left lobe drainage group (left drainage), and left lobe drainage with right PVE portal vein embolization group (left drainage with right PVE portal vein embolization ). Percentage volume and percentage function were measured in each lobe using fusion imaging. The ratio between percentage function and percentage volume (the function-to-volume ratio) was calculated for each lobe, and the results were compared among the four groups. Statistical analysis was performed with Wilcoxon signed-rank tests and Mann-Whitney U tests. The median values for the function-to-volume ratio in the right drainage, bilateral drainage, left drainage, and left drainage with right PVE portal vein embolization group were 1.12, 1.05, 1.02, and 0.81 in the right lobe; and 0.51, 0.88, 0.96, and 1.17 in the left lobe. Significant differences in the function-to-volume ratio were observed among the four groups (right drainage vs bilateral

  18. Intracranial EEG in predicting surgical outcome in frontal lobe epilepsy.

    Science.gov (United States)

    Holtkamp, Martin; Sharan, Ashwini; Sperling, Michael R

    2012-10-01

    Surgery in frontal lobe epilepsy (FLE) has a worse prognosis regarding seizure freedom than anterior lobectomy in temporal lobe epilepsy. The current study aimed to assess whether intracranial interictal and ictal EEG findings in addition to clinical and scalp EEG data help to predict outcome in a series of patients who needed invasive recording for FLE surgery. Patients with FLE who had resective surgery after chronic intracranial EEG recording were included. Outcome predictors were compared in patients with seizure freedom (group 1) and those with recurrent seizures (group 2) at 19-24 months after surgery. Twenty-five patients (16 female) were included in this study. Mean age of patients at epilepsy surgery was 32.3 ± 15.6 years (range 12-70); mean duration of epilepsy was 16.9 ± 13.4 years (range 1-48). In each outcome group, magnetic resonance imaging revealed frontal lobe lesions in three patients. Fifteen patients (60%) were seizure-free (Engel class 1), 10 patients (40%) continued to have seizures (two were class II, three were class III, and five were class IV). Lack of seizure freedom was seen more often in patients with epilepsy surgery on the left frontal lobe (group 1, 13%; group 2, 70%; p = 0.009) and on the dominant (27%; 70%; p = 0.049) hemisphere as well as in patients without aura (29%; 80%; p = 0.036), whereas sex, age at surgery, duration of epilepsy, and presence of an MRI lesion in the frontal lobe or extrafrontal structures were not different between groups. Electroencephalographic characteristics associated with lack of seizure freedom included presence of interictal epileptiform discharges in scalp recordings (31%; 90%; p = 0.01). Detailed analysis of intracranial EEG revealed widespread (>2 cm) (13%; 70%; p = 0.01) in contrast to focal seizure onset as well as shorter latency to onset of seizure spread (5.8 ± 6.1 s; 1.5 ± 2.3 s; p = 0.016) and to ictal involvement of brain structures beyond the frontal lobe (23.5 ± 22.4 s; 5.8 ± 5.4 s

  19. Single photon emission computed tomography in motor neuron disease with dementia

    Energy Technology Data Exchange (ETDEWEB)

    Sawada, H.; Udaka, F.; Kishi, Y.; Seriu, N.; Ohtani, S.; Abe, K.; Mezaki, T.; Kameyama, M.; Honda, M.; Tomonobu, M.

    1988-12-01

    Single photon emission computed tomography with (123 I) isopropylamphetamine was carried out on a patient with motor neutron disease with dementia. (123 I) uptake was decreased in the frontal lobes. This would reflect the histopathological findings such as neuronal loss and gliosis in the frontal lobes.

  20. Single photon emission computed tomography in motor neuron disease with dementia.

    Science.gov (United States)

    Sawada, H; Udaka, F; Kishi, Y; Seriu, N; Mezaki, T; Kameyama, M; Honda, M; Tomonobu, M

    1988-01-01

    Single photon emission computed tomography with [123 I] isopropylamphetamine was carried out on a patient with motor neuron disease with dementia. [123 I] uptake was decreased in the frontal lobes. This would reflect the histopathological findings such as neuronal loss and gliosis in the frontal lobes.

  1. Emotional reactions in patients after frontal lobe stroke

    Directory of Open Access Journals (Sweden)

    Stojanović Zlatan

    2015-01-01

    Full Text Available Background/Aim. Emotional reactions have been documented after tumor lesions and the other damages of the brain. The aim of this paper was to examine the correlation between frontal lobe lesions and emotional reactions in patients with stroke. Methods. The research included 118 patients after stroke. Lesion localization was defined on computed axial tomography records, whereas the area and perimeter of lesion were measured by AutoCAD 2004 software. Examinations by means of the Hamilton Rating Scale for Anxiety and Depression (HRSA and HRSD were carried out 11-40 days after stroke. Statistic data were processed by simple linear/nonlinear regression, Cox's and the generalized linear model. Results. A higher frequency of emotional reactions, i.e. anxiety, was determined in women after stroke (p = 0.024. A negative correlation between the lesion size and the intensity of anxiety manifestations was determined (Spearman’s r = -0.297; p = 0.001. Anxiety was more frequent in patients with frontal lobe lesions in the dominant hemisphere (interaction: frontal lesion * hand dominant hemisphere, p = 0.017. Also, HRSD score values showed the tendency for lesser decline in case of greater frontal lobe lesions in relation to lesions of other regions of prosencephalon (interaction: frontal lesion * lesion area, p = 0.001. Conclusion. The results of this study indicate the correlation between evolutionary younger structures of the central nervous system and emotional reactions of man. Therefore, it is necessary to undertake proper early psychopharmacotherapy in the vulnerable group of patients.

  2. Distinct frontal lobe morphology in girls and boys with ADHD.

    Science.gov (United States)

    Dirlikov, Benjamin; Shiels Rosch, Keri; Crocetti, Deana; Denckla, Martha B; Mahone, E Mark; Mostofsky, Stewart H

    2015-01-01

    This study investigated whether frontal lobe cortical morphology differs for boys and girls with ADHD (ages 8-12 years) in comparison to typically developing (TD) peers. Participants included 226 children between the ages of 8-12 including 93 children with ADHD (29 girls) and 133 TD children (42 girls) for which 3T MPRAGE MRI scans were obtained. A fully automated frontal lobe atlas was used to generate functionally distinct frontal subdivisions, with surface area (SA) and cortical thickness (CT) assessed in each region. Analyses focused on overall diagnostic differences as well as examinations of the effect of diagnosis within boys and girls. Girls, but not boys, with ADHD showed overall reductions in total prefrontal cortex (PFC) SA. Localization revealed that girls showed widely distributed reductions in the bilateral dorsolateral PFC, left inferior lateral PFC, right medial PFC, right orbitofrontal cortex, and left anterior cingulate; and boys showed reduced SA only in the right anterior cingulate and left medial PFC. In contrast, boys, but not girls, with ADHD showed overall reductions in total premotor cortex (PMC) SA. Further localization revealed that in boys, premotor reductions were observed in bilateral lateral PMC regions; and in girls reductions were observed in bilateral supplementary motor complex. In line with diagnostic group differences, PMC and PFC SAs were inversely correlated with symptom severity in both girls and boys with ADHD. These results elucidate sex-based differences in cortical morphology of functional subdivisions of the frontal lobe and provide additional evidence of associations among SA and symptom severity in children with ADHD.

  3. Differences in the neural correlates of frontal lobe tests.

    Science.gov (United States)

    Matsuoka, Teruyuki; Kato, Yuka; Imai, Ayu; Fujimoto, Hiroshi; Shibata, Keisuke; Nakamura, Kaeko; Yamada, Kei; Narumoto, Jin

    2018-01-01

    The Executive Interview (EXIT25), the executive clock-drawing task (CLOX1), and the Frontal Assessment Battery (FAB) are used to assess executive function at the bedside. These tests assess distinct psychometric properties. The aim of this study was to examine differences in the neural correlates of the EXIT25, CLOX1, and FAB based on magnetic resonance imaging. Fifty-eight subjects (30 with Alzheimer's disease, 10 with mild cognitive impairment, and 18 healthy controls) participated in this study. Multiple regression analyses were performed to examine the brain regions correlated with the EXIT25, CLOX1, and FAB scores. Age, gender, and years of education were included as covariates. Statistical thresholds were set to uncorrected P-values of 0.001 at the voxel level and 0.05 at the cluster level. The EXIT25 score correlated inversely with the regional grey matter volume in the left lateral frontal lobe (Brodmann areas 6, 9, 44, and 45). The CLOX1 score correlated positively with the regional grey matter volume in the right orbitofrontal cortex (Brodmann area 11) and the left supramarginal gyrus (Brodmann area 40). The FAB score correlated positively with the regional grey matter volume in the right precentral gyrus (Brodmann area 6). The left lateral frontal lobe (Brodmann area 9) and the right lateral frontal lobe (Brodmann area 46) were identified as common brain regions that showed association with EXIT25, CLOX1, and FAB based only a voxel-level threshold. The results of this study suggest that the EXIT25, CLOX1, and FAB may be associated with the distinct neural correlates of the frontal cortex. © 2018 Japanese Psychogeriatric Society.

  4. Frontal lobe seizures: from clinical semiology to localization.

    Science.gov (United States)

    Bonini, Francesca; McGonigal, Aileen; Trébuchon, Agnès; Gavaret, Martine; Bartolomei, Fabrice; Giusiano, Bernard; Chauvel, Patrick

    2014-02-01

    Frontal lobe seizures are difficult to characterize according to semiologic and electrical features. We wished to establish whether different semiologic subgroups can be identified and whether these relate to anatomic organization. We assessed all seizures from 54 patients with frontal lobe epilepsy that were explored with stereoelectroencephalography (SEEG) during presurgical evaluation. Semiologic features and concomitant intracerebral EEG changes were documented and quantified. These variables were examined using Principal Component Analysis and Cluster Analysis, and semiologic features correlated with anatomic localization. Four main groups of patients were identified according to semiologic features, and correlated with specific patterns of anatomic seizure localization. Group 1 was characterized clinically by elementary motor signs and involved precentral and premotor regions. Group 2 was characterized by a combination of elementary motor signs and nonintegrated gestural motor behavior, and involved both premotor and prefrontal regions. Group 3 was characterized by integrated gestural motor behavior with distal stereotypies and involved anterior lateral and medial prefrontal regions. Group 4 was characterized by seizures with fearful behavior and involved the paralimbic system (ventromedial prefrontal cortex ± anterior temporal structures). The groups were organized along a rostrocaudal axis, representing bands within a spectrum rather than rigid categories. The more anterior the seizure organization, the more likely was the occurrence of integrated behavior during seizures. Distal stereotypies were associated with the most anterior prefrontal localizations, whereas proximal stereotypies occurred in more posterior prefrontal regions. Meaningful categorization of frontal seizures in terms of semiology is possible and correlates with anatomic organization along a rostrocaudal axis, in keeping with current hypotheses of frontal lobe hierarchical organization

  5. Comparing Clinical Outcomes in Upper versus Lower Lobe Endobronchial Valve Treatment in Severe Emphysema.

    Science.gov (United States)

    Eberhardt, Ralf; Herth, Felix J F; Radhakrishnan, Sri; Gompelmann, Daniela

    2015-01-01

    Lung volume reduction surgery has been recommended for patients with upper lobe predominant emphysema and was associated with less favorable outcomes in patients with non-upper lobe predominant emphysema. The value of endobronchial valve (EBV) treatment in lower lobe predominant emphysema has not been studied. To confirm the equivalence of upper and lower lobe valve treatments in patients with heterogeneous emphysema. A retrospective analysis from the Endobronchial Valve for Emphysema Palliation Trial (VENT), where patients with heterogeneous emphysema received Zephyr® EBV (Pulmonx Corp., Redwood City, Calif., USA) or medical treatment, was performed. Patients with low interlobar collateral ventilation and accurate placement of valves in the target lobes were identified. Safety and efficacy were compared between patients who underwent upper versus lower lobe treatment. Of the 331 patients, 60 had low interlobar collateral ventilation and successful lobar exclusion (45 patients with upper lobe treatment and 15 patients with lower lobe treatment). There was no difference in baseline characteristics between the groups except for a higher destruction score (70.3 vs. 60.7%; p = 0.0010) and a higher heterogeneity index (24 vs. 13%; p = 0.0005) for the upper lobe cohort. At 180 days, both groups had improved clinically. There were no significant differences in mean changes or responder rates of forced expiratory volume in 1 s (+23.8 vs. +22.9%), the St. Georges Respiratory Questionnaire (-6.50 vs. -7.53 points), the 6-min walk test (+24.1 vs. +44.0 m), target lobe volume reduction (-1,199 vs. -1,042 ml), or in the adverse event rate between both cohorts. Patients with lower and upper lobe predominant emphysema benefit equally from EBV therapy when interlobar collateral ventilation is low and lobar exclusion is achieved. Patients with lower lobe disease did not have increased adverse events compared to patients with upper lobe emphysema. © 2015 S. Karger AG, Basel.

  6. Upper lobe pulmonary edema and dry gangrene in scorpion sting

    Directory of Open Access Journals (Sweden)

    Stalin Viswanathan

    2011-06-01

    Full Text Available A 17 year old student admitted to our hospital following a red scorpion sting had pulmonary edema and hypotension. Chest radiography revealed asymmetrical upper lobe pulmonary edema with air bronchogram. Due to high counts, antibiotics were initiated. Chest radiograph indicated that the chest radiography abnormalities were improved within 36 hours. Thirty hours after admission he developed discoloration of left foot which was managed conservatively with heparin and warfarin. His inotropes were gradually tapered and stopped 78 hours after admission. Echocardiography repeated on the sixth day of his admission was normal. He was discharged on pentoxyphylline, warfarin and tramadol since there was no surgical intervention possible due to poor demarcation.

  7. Wideband Low Side Lobe Aperture Coupled Patch Phased Array Antennas

    Science.gov (United States)

    Poduval, Dhruva

    Low profile printed antenna arrays with wide bandwidth, high gain, and low Side Lobe Level (SLL) are in great demand for current and future commercial and military communication systems and radar. Aperture coupled patch antennas have been proposed to obtain wide impedance bandwidths in the past. Aperture coupling is preferred particularly for phased arrays because of their advantage of integration to other active devices and circuits, e.g. phase shifters, power amplifiers, low noise amplifiers, mixers etc. However, when designing such arrays, the interplay between array performance characteristics, such as gain, side lobe level, back lobe level, mutual coupling etc. must be understood and optimized under multiple design constraints, e.g. substrate material properties and thicknesses, element to element spacing, and feed lines and their orientation and arrangements with respect to the antenna elements. The focus of this thesis is to investigate, design, and develop an aperture coupled patch array with wide operating bandwidth (30%), high gain (17.5 dBi), low side lobe level (20 dB), and high Forward to Backward (F/B) ratio (21.8 dB). The target frequency range is 2.4 to 3 GHz given its wide application in WLAN, LTE (Long Term Evolution) and other communication systems. Notwithstanding that the design concept can very well be adapted at other frequencies. Specifically, a 16 element, 4 by 4 planar microstrip patch array is designed using HFSS and experimentally developed and tested. Starting from mutual coupling minimization a corporate feeding scheme is designed to achieve the needed performance. To reduce the SLL the corporate feeding network is redesigned to obtain a specific amplitude taper. Studies are conducted to determine the optimum location for a metallic reflector under the feed line to improve the F/B. An experimental prototype of the antenna was built and tested validating and demonstrating the performance levels expected from simulation predictions

  8. Language Mapping in Temporal Lobe Epilepsy in Children: Special Considerations

    Science.gov (United States)

    de Ribaupierre, Sandrine; Wang, An; Hayman-Abello, Susan

    2012-01-01

    Temporal lobe epilepsy (TLE) in children is a slightly different entity than TLE in adults not only because of its semiology and pathology but also because of the different approach to surgical treatment. Presurgical investigations for eloquent cortex, especially language, must take these differences into account. Most diagnostic tests were created for adults, and many of the assessment tools need to be adapted for children because they are not just small adults. This paper will highlight the specific challenges and solutions in mapping language in a pediatric population with TLE. PMID:22957246

  9. Lithium therapy in comorbid temporal lobe epilepsy and cycloid psychosis.

    Science.gov (United States)

    Brown, Paul; Kashiviswanath, Sridhar; Huynh, Alison; Allha, Naveen; Piaggio, Ken; Sahoo, Saddichha; Gupta, Ankur

    2016-12-01

    The treatment of post-ictal psychosis has foundered on uncertainty in diagnosis of psychotic phenotypes, and equivocal efficacy of first and second generation antipsychotics. This article presents a case history of comorbid temporal lobe epilepsy and psychosis, suggests the applicability of the continental, cycloid psychosis diagnostic conceptualization to post-ictal psychoses, and demonstrates the efficacy of lithium in their treatment. Clinical studies of comorbidity of epilepsy and psychosis offer great potential as a basis for modelling brain-mind relationships, and neuropsychiatric nosology, pathophysiology and treatment.

  10. Tsunami risk assessment in the Marquesas Islands (French Polynesia through numerical modeling of generic far-field events

    Directory of Open Access Journals (Sweden)

    H. Hébert

    2001-01-01

    Full Text Available Earthquakes occurring at the Pacific Rim can trigger tsunamis that propagate across the ocean and can produce significant damages far away from the source. In French Polynesia, the Marquesas Islands are the most exposed to the far-field tsunami hazards, since they are not protected by any outer coral reef and since submarine slopes are less steep than in other islands. Between 1994 and 1996, four tsunamis have reached the bays of the archipelago, among them, the tsunami initiated by the Chilean Mw 8.1 earthquake, produced up to 3 m high waves in Tahauku Bay. Numerical modeling of these recent events has already allowed us to validate our method of resolution of hydrodynamics laws through a finite-difference scheme that simulates the propagation of the tsunamis across the ocean and computes the inundation heights (run-up in remote bays. We present in this paper the simulations carried out to study potentially threatening areas located at the Pacific Rim, on the seismogenic Aleutian and Tonga subduction zones. We use a constant seismic moment source (that of the Mw 8.1 Chile 1995 earthquake, M0 = 1.2 1021 N.m located at several potential epicenters, with the fault strike adapted from the regional seismotectonics pattern. Our results show that the sources chosen in the Aleutian trench do not produce large inundations in the Marquesas bays, except for the easternmost source (longitude 194° E. Sources located in the Tonga trench do not produce high amplifications either, except for the northernmost one (latitude 16° S. We also discuss the behaviour of the tsunami waves within the archipelago, and evidence contrasting responses depending on the arrival azimuths. These results show that, for a given initial seismic energy, the tsunami amplification in remote bays is highly dependent on the source location and fault strike.

  11. The timing of associative memory formation: frontal lobe and anterior medial temporal lobe activity at associative binding predicts memory

    Science.gov (United States)

    Hales, J. B.

    2011-01-01

    The process of associating items encountered over time and across variable time delays is fundamental for creating memories in daily life, such as for stories and episodes. Forming associative memory for temporally discontiguous items involves medial temporal lobe structures and additional neocortical processing regions, including prefrontal cortex, parietal lobe, and lateral occipital regions. However, most prior memory studies, using concurrently presented stimuli, have failed to examine the temporal aspect of successful associative memory formation to identify when activity in these brain regions is predictive of associative memory formation. In the current study, functional MRI data were acquired while subjects were shown pairs of sequentially presented visual images with a fixed interitem delay within pairs. This design allowed the entire time course of the trial to be analyzed, starting from onset of the first item, across the 5.5-s delay period, and through offset of the second item. Subjects then completed a postscan recognition test for the items and associations they encoded during the scan and their confidence for each. After controlling for item-memory strength, we isolated brain regions selectively involved in associative encoding. Consistent with prior findings, increased regional activity predicting subsequent associative memory success was found in anterior medial temporal lobe regions of left perirhinal and entorhinal cortices and in left prefrontal cortex and lateral occipital regions. The temporal separation within each pair, however, allowed extension of these findings by isolating the timing of regional involvement, showing that increased response in these regions occurs during binding but not during maintenance. PMID:21248058

  12. Comprehension and production of nouns and verbs in temporal lobe epilepsy.

    Science.gov (United States)

    Yurchenko, Anna; Golovteev, Alexander; Kopachev, Dmitry; Dragoy, Olga

    2017-10-01

    Previous research on linguistic performance at the single-word level in patients with temporal lobe epilepsy (TLE) has mostly been limited to the comprehension and production of nouns, and findings have been inconsistent. Results are likewise limited and controversial regarding the lateralization of the epileptogenic focus. The present study investigates comprehension and production of nouns and verbs in patients with left and right TLE (12 in each group). We designed a comprehension (word-picture matching) test and a production (naming) test, matched on a range of psycholinguistic parameters for the two word classes. The results showed impaired verb comprehension in patients with left TLE and impaired noun and verb production in both groups of patients compared to the control group. Patients with left and right TLE differed significantly on verb comprehension and noun production, whereas verb production was equally impaired in the two groups of patients. These findings suggest difficulties with single-word processing in patients with both left and right TLE, which are more prominent for verbs than for nouns in patients with left TLE. The verb production (action naming) test turned out to be the most effective tool for assessing linguistic difficulties at the single-word level in patients with TLE. Copyright © 2017 Elsevier Inc. All rights reserved.

  13. Observations of significant flux closure by dual lobe reconnection

    Directory of Open Access Journals (Sweden)

    S. M. Imber

    2007-07-01

    Full Text Available We present an interval of dual lobe reconnection during which interplanetary magnetic field lines are captured by the magnetosphere by reconnecting at high latitudes in both the Northern and the Southern Hemispheres. This event was identified using measurements of the ionospheric convection flow and observations of the aurora using the SuperDARN radars and the IMAGE spacecraft. A cusp spot, characteristic of northward IMF, is clearly visible for a 30 min period enabling the ionospheric footprint of the Northern Hemisphere merging gap to be accurately determined. During the interval a strong burst of sunward flow across the dayside open/closed field line boundary (OCB is observed, which we interpret as the reconfiguration of the magnetosphere following a burst of reconnection. Noon-midnight and dawn-dusk keograms of the aurora show that the polar cap shrinks during the interval indicating that a large amount of flux was closed by the reconnection. Using the SuperDARN potential maps it is possible to calculate that the amount of flux closed during the interval is 0.13 GWb which represents approximately 10% of the pre-existing polar cap. The number of ions captured by the burst of dual lobe reconnection was calculated to be ~2.2×1031, more than sufficient to populate a cold, dense plasma sheet. That a dense plasma sheet was not subsequently observed is discussed in terms of subsequent changes in the IMF.

  14. Creative innovation with temporal lobe epilepsy and lobectomy.

    Science.gov (United States)

    Ghacibeh, Georges A; Heilman, Kenneth M

    2013-01-15

    Some patients with left temporal degeneration develop visual artistic abilities. These new artistic abilities may be due to disinhibition of the visuo-spatially dominant right hemisphere. Many famous artists have had epilepsy and it is possible that some may have had left temporal seizures (LTS) and this left temporal dysfunction disinhibited their right hemisphere. Alternatively, unilateral epilepsy may alter intrahemispheric connectivity and right anterior temporal lobe seizures (RTS) may have increased these artists' right hemisphere mediated visual artistic creativity. To test the disinhibition versus enhanced connectivity hypotheses we studied 9 participants with RTS and 9 with left anterior temporal seizures (LTS) who underwent unilateral lobectomy for the treatment of medically refractory epilepsy. Creativity was tested using the Torrance Test of Creative Thinking (TTCT). There were no between group differences in either the verbal or figural scores of the TTCT, suggesting that unilateral anterior temporal ablation did not enhance visual artistic ability; however, for the RTS participants' figural creativity scores were significantly higher than verbal scores. Whereas these results fail to support the left temporal lobe disinhibition postulate of enhanced figural creativity, the finding that the patients with RTS had better figural than verbal creativity suggests that their recurrent right hemispheric seizures lead to changes in their right hemispheric networks that facilitated visual creativity. To obtain converging evidence, studies on RTS participants who have not undergone lobectomy will need to be performed. Published by Elsevier B.V.

  15. Episodic and Semantic Autobiographical Memory in Temporal Lobe Epilepsy

    Directory of Open Access Journals (Sweden)

    Claudia P. Múnera

    2014-01-01

    Full Text Available Autobiographical memory (AM is understood as the retrieval of personal experiences that occurred in specific time and space. To date, there is no consensus on the role of medial temporal lobe structures in AM. Therefore, we investigated AM in medial temporal lobe epilepsy (TLE patients. Twenty TLE patients candidates for surgical treatment, 10 right (RTLE and 10 left (LTLE, and 20 healthy controls were examined with a version of the Autobiographical Interview adapted to Spanish language. Episodic and semantic AM were analyzed during five life periods through two conditions: recall and specific probe. AM scores were compared with clinical and cognitive data. TLE patients showed lower performance in episodic AM than healthy controls, being significantly worst in RTLE group and after specific probe. In relation to semantic AM, LTLE retrieved higher amount of total semantic details compared to controls during recall, but not after specific probe. No significant differences were found between RTLE and LTLE, but a trend towards poorer performance in RTLE group was found. TLE patients obtained lower scores for adolescence period memories after specific probe. Our findings support the idea that the right hippocampus would play a more important role in episodic retrieval than the left, regardless of a temporal gradient.

  16. Decision making in patients with temporal lobe epilepsy.

    Science.gov (United States)

    Labudda, Kirsten; Frigge, Kristina; Horstmann, Simone; Aengenendt, Joerg; Woermann, Friedrich G; Ebner, Alois; Markowitsch, Hans J; Brand, Matthias

    2009-01-01

    The mesiotemporal lobe is involved in decision making processes because bilateral amygdala damage can cause impairments in decision making that is mainly based on the processing of emotional feedback. In addition to executive functions, previous studies have suggested the involvement of feedback processing in decision making under risk when explicit information about consequences and their probabilities is provided. In the current study, we investigated whether unilateral mesiotemporal damage, comprising of the hippocampus and/or the amygdala, results in alterations of both kinds of decision making. For this purpose, we preoperatively examined 20 patients with refractory unilateral mesiotemporal lobe epilepsy (TLE) and a comparison group (CG) of 20 healthy volunteers with the Iowa Gambling Task to assess decision making based on feedback processing, the Game of Dice Task to assess decision making under risk, and with a neuropsychological test battery. Results indicate that TLE patients performed normally in decision making under risk, but can exhibit disturbances in decision making on the Iowa Gambling Task. A subgroup analysis revealed that those patients with a preference for the disadvantageous alternatives performed worse on executive subcomponents and had seizure onset at an earlier age in comparison to the patient subgroup without disadvantageous decision making. Furthermore, disadvantageous decision making can emerge in patients with selective hippocampal sclerosis not extended to the amygdala. Thus, our results demonstrate for the first time that presurgical patients with TLE can have selective reductions in decision making and that these deficits can result from hippocampal lesions without structural amygdala abnormalities.

  17. Do children with aggressive behavior have temporal lobe changes?

    International Nuclear Information System (INIS)

    Thomas, C.T.; Mishkin, F.; Goldberg, M.

    2002-01-01

    Aggressive behavior and mood disorders may afflict children. One problem is the lack of objective data to arrive at a specific clinical diagnosis. Abnormalities in neurotransmitters such as serotonin, dopamine, acetylcholine and gamma-aminobutyric acid have been reported to play an important role in the onset of these disorders. We studied 8 patients, 3 girls and 5 boys, ages ranging from 6 to 12, referred to us with the diagnosis of ADHD or autism and reported as having temper problems by their families. These patients were injected with a dose of Tc-99m HMPAO calculated according to patient age and weight and were imaged 1 hour later using a Picker camera with Fan Beam collimators. We analyzed the brain SPECT using 3D as well as the traditional transverse, coronal and sagittal images. With the help of surface rendered 3D images with a cut off of 88% (high) and 60-65% (lower value depending on the patient RCBF value), we observed increased perfusion or activation of either or both right and left temporal lobes in all 8 of the patients. This pattern was not seen in children whose parents did not report temper problems. Increase in perfusion to the temporal lobes may indicate an association with oppositional or aggressive behavior that may be amenable to treatment. Brain SPECT may be useful not only in early diagnosis, but also in guiding appropriate therapy

  18. Preoperative neuropsychological presentation of patients with refractory frontal lobe epilepsy.

    Science.gov (United States)

    Patrikelis, Panayiotis; Gatzonis, Stylianos; Siatouni, Anna; Angelopoulos, Elias; Konstantakopoulos, George; Takousi, Maria; Sakas, Damianos E; Zalonis, Ioannis

    2016-06-01

    This study investigated whether certain cognitive deficits are associated with frontal lobe epilepsy (FLE) aiming to contribute with localization data to the preoperative assessment of epilepsy surgery candidates. We evaluated 34 patients with refractory FLE, 37 patients with refractory medial temporal lobe epilepsy (MTLE), and 22 healthy individuals in attention, psychomotor speed, motor function, verbal memory span, verbal fluency, response inhibition/interference, concept formation and set shifting, anticipation and planning, global memory. Neuropsychological performances of FLE and MTLE were similar, with the only exception the WCST-number of categories index, measuring mental flexibility, in which MTLE patients performed significantly worse than FLE patients. Left-FLE patients presented more perseverative responding compared to both other patient groups and healthy controls (HCs), while left-MTLE patients showed worse sorting abilities than the other epilepsy groups. Our findings suggest a weak cognitive differentiation between FLE and MTLE, probably attributed to the intricate nature of fronto-temporal connectivity frequently resulting in overlapping deficits as well as the confounding effects of seizure-related variables. In clinical practice, a highly individualized (idiographic) neuropsychological approach along with the inclusion of concurrent EEG recordings (e.g., interictal coupling) may be of help for neuropsychologists in identifying FLE patients from those with medial temporal pathology presenting frontal dysfunction as a secondary cognitive symptom.

  19. MRI parcellation of ex vivo medial temporal lobe.

    Science.gov (United States)

    Augustinack, Jean C; Magnain, Caroline; Reuter, Martin; van der Kouwe, André J W; Boas, David; Fischl, Bruce

    2014-06-01

    Recent advancements in radio frequency coils, field strength and sophisticated pulse sequences have propelled modern brain mapping and have made validation to biological standards - histology and pathology - possible. The medial temporal lobe has long been established as a pivotal brain region for connectivity, function and unique structure in the human brain, and reveals disconnection in mild Alzheimer's disease. Specific brain mapping of mesocortical areas affected with neurofibrillary tangle pathology early in disease progression provides not only an accurate description for location of these areas but also supplies spherical coordinates that allow comparison between other ex vivo cases and larger in vivo datasets. We have identified several cytoarchitectonic features in the medial temporal lobe with high resolution ex vivo MRI, including gray matter structures such as the entorhinal layer II 'islands', perirhinal layer II-III columns, presubicular 'clouds', granule cell layer of the dentate gyrus as well as lamina of the hippocampus. Localization of Brodmann areas 28 and 35 (entorhinal and perirhinal, respectively) demonstrates MRI based area boundaries validated with multiple methods and histological stains. Based on our findings, both myelin and Nissl staining relate to contrast in ex vivo MRI. Precise brain mapping serves to create modern atlases for cortical areas, allowing accurate localization with important applications to detecting early disease processes. Copyright © 2013 Elsevier Inc. All rights reserved.

  20. Adult absence semiology misinterpreted as mesial temporal lobe epilepsy.

    Science.gov (United States)

    Hurst, Rebecca; Chiota-McCollum, Nicole; Tatum, William

    2014-12-01

    Correct diagnosis of seizure type and epilepsy syndrome is the foundation for appropriate antiepileptic drug selection. Inappropriate medication choices occur in the treatment of generalized epilepsy and may aggravate some seizure types, including absence seizures, potentially leading to pseudo-drug resistance. Fortunately, a correct diagnosis of absence seizures is usually not difficult, though rarely demonstrates electroclinical overlap with focal seizures. EEG can be especially misleading when secondary bilateral synchronous discharges occur in patients with focal seizures. However, the semiology of focal seizures associated with mesial temporal lobe epilepsy has a characteristic and consistent semiology that is the mark of this common epilepsy syndrome in adulthood. We recently encountered a 53-year-old female with refractory seizures and a semiology strongly suggesting mesial temporal lobe epilepsy. Instead of focal seizures, prolonged absence seizures were validated by video-EEG monitoring and she became seizure-free after a change to broad-spectrum antiepileptic drugs. This case further expands our understanding of the complexity of semiology in electroclinical classification and the spectrum that may occur in adult absence seizures. It serves to underscore the need for ictal EEG recordings and the importance of concordance with the clinical course during the pre-surgical evaluation of patients with lesions and drug-resistant epilepsy. [Published with video sequences].

  1. Preoperative amygdala fMRI in temporal lobe epilepsy.

    Science.gov (United States)

    Bonelli, Silvia B; Powell, Robert; Yogarajah, Mahinda; Thompson, Pamela J; Symms, Mark R; Koepp, Matthias J; Duncan, John S

    2009-02-01

    Anterior temporal lobe resections (ATLR) benefit 70% of patients with refractory mesial temporal lobe epilepsy (TLE), but may be complicated by emotional disturbances. We used functional magnetic resonance imaging (fMRI) to investigate the role of the amygdala in processing emotions in TLE and whether this may be a potential preoperative predictive marker for emotional disturbances following surgery. We studied 54 patients with refractory mesial TLE due to hippocampal sclerosis (28 right, 26 left) and 21 healthy controls using a memory encoding fMRI paradigm, which included viewing fearful and neutral faces. Twenty-one TLE patients (10 left, 11 right) subsequently underwent ATLR. Anxiety and depression were assessed preoperatively and 4 months postoperatively using the Hospital Anxiety and Depression Scale. On viewing fearful faces, healthy controls demonstrated left lateralized, while right TLE patients showed bilateral amygdala activation. Left TLE patients had significantly reduced activation in left and right amygdalae compared to controls and right TLE patients. In right TLE patients, left and right amygdala activation was significantly related to preoperative anxiety and depression levels, and preoperative right amygdala activation correlated significantly with postoperative change of anxiety and depression scores, characterized by greater increases in anxiety and depression in patients with greater preoperative activation. No such correlations were seen for left TLE patients. The fearful face fMRI paradigm is a reliable method for visualizing amygdala activation in controls and patients with mesial TLE. Activation of the right amygdala preoperatively was predictive of emotional disturbances following right ATLR.

  2. Connectome Reorganization Associated With Surgical Outcome in Temporal Lobe Epilepsy.

    Science.gov (United States)

    Ji, Gong-Jun; Zhang, Zhiqiang; Xu, Qiang; Wei, Wei; Wang, Jue; Wang, Zhengge; Yang, Fang; Sun, Kangjian; Jiao, Qing; Liao, Wei; Lu, Guangming

    2015-10-01

    To identify the distinct pattern of anatomical network reorganization in surgically refractory mesial temporal lobe epilepsy (MTLE) patients using a longitudinal design. We collected longitudinal diffusion-weighted images of 19 MTLE patients before and after anterior temporal lobectomy. Patients were classified as seizure-free (SF) or nonseizure-free (NSF) at least 1 year after surgery. We constructed whole-brain anatomical networks derived from white matter tractography and evaluated network connectivity measures by graph theoretical analysis. The reorganization trajectories of network measures in SF and NSF patients were investigated by two-way mixed analysis of variance, with factors "group" (SF vs NSF) and "treatment" (presurgery vs postsurgery). Widespread brain structures showed opposite reorganization trajectories in FS and NSF groups (interaction effect). Most of them showed group difference before surgery and then converge after surgery, suggesting that surgery remodeled these structures into a similar status. Conversly, contralateral amygdala-planum-temporale and thalamic-parietal tracts showed higher connectivity strength in NSF than in SF patients after surgery, indicating maladaptive neuroplastic responses to surgery in NSF patients. Our findings suggest that surgical outcomes are associated not only with the preoperative pattern of anatomical connectivity, but also with connectome reconfiguration following surgery. The reorganization of contralateral temporal lobe and corticothalamic tracts may be particularly important for seizure control in MTLE.

  3. Focal cortical dysplasia of the temporal lobe with late-onset partial epilepsy: serial quantitative MRI

    International Nuclear Information System (INIS)

    Rademacher, J.; Seitz, R.J.; Aulich, A.; Reifenberger, G.; Kiwit, J.C.W.; Langen, K.J.; Schmidt, D.

    2000-01-01

    We describe serial studies of focal cortical dysplasia causing temporal lobe seizures and progressive aphasia in a 54-year-old woman. Initially, MRI volumetry of the temporal lobes showed significant left cortical thickening corresponding to an elevated aminoacid uptake in the left temporoparietal and inferior frontal cortex on SPECT using 3-[ 123 I]iodo-α-methyl-l-tyrosine (IMT). After 1 year there was severe shrinkage of the left temporal lobe, possibly the result of recurrent complex partial seizures. (orig.)

  4. Focal cortical dysplasia of the temporal lobe with late-onset partial epilepsy: serial quantitative MRI

    Energy Technology Data Exchange (ETDEWEB)

    Rademacher, J.; Seitz, R.J. [Department of Neurology, Heinrich-Heine University Duesseldorf (Germany); Aulich, A. [Department of Radiology, Heinrich-Heine University, Duesseldorf (Germany); Reifenberger, G. [Department of Neuropathology, Heinrich-Heine University, Duesseldorf (Germany); Kiwit, J.C.W. [Department of Neurosurgery, Heinrich-Heine University, Duesseldorf (Germany); Langen, K.J.; Schmidt, D. [Institute of Medicine, Research Center Juelich, Heinrich-Heine University, Duesseldorf (Germany)

    2000-06-01

    We describe serial studies of focal cortical dysplasia causing temporal lobe seizures and progressive aphasia in a 54-year-old woman. Initially, MRI volumetry of the temporal lobes showed significant left cortical thickening corresponding to an elevated aminoacid uptake in the left temporoparietal and inferior frontal cortex on SPECT using 3-[{sup 123}I]iodo-{alpha}-methyl-l-tyrosine (IMT). After 1 year there was severe shrinkage of the left temporal lobe, possibly the result of recurrent complex partial seizures. (orig.)

  5. The morphology of the cephalic lobes and anterior pectoral fins in six species of batoids.

    Science.gov (United States)

    Mulvany, Samantha; Motta, Philip J

    2013-09-01

    Many benthic batoids utilize their pectoral fins for both undulatory locomotion and feeding. Certain derived, pelagic species of batoids possess cephalic lobes, which evolved from the anterior pectoral fins. These species utilize the pectoral fins for oscillatory locomotion while the cephalic lobes are used for feeding. The goal of this article was to compare the morphology of the cephalic lobes and anterior pectoral fins in species that possess and lack cephalic lobes. The skeletal elements (radials) of the cephalic lobes more closely resembled the radials in the pectoral fin of undulatory species. Second moment of area (I), calculated from cephalic lobe radial cross sections, and the number of joints revealed greater flexibility and resistance to bending in multiple directions as compared to pectoral fin radials of oscillatory species. The cephalic lobe musculature was more complex than the anterior pectoral fin musculature, with an additional muscle on the dorsal side, with fiber angles running obliquely to the radials. In Rhinoptera bonasus, a muscle presumably used to help elevate the cephalic lobes is described. Electrosensory pores were found on the cephalic lobes (except Mobula japonica) and anterior pectoral fins of undulatory swimmers, but absent from the anterior pectoral fins of oscillatory swimmers. Pore distributions were fairly uniform except in R. bonasus, which had higher pore numbers at the edges of the cephalic lobes. Overall, the cephalic lobes are unique in their anatomy but are more similar to the anterior pectoral fins of undulatory swimmers, having more flexibility and maneuverability compared to pectoral fins of oscillatory swimmers. The maneuverable cephalic lobes taking on the role of feeding may have allowed the switch to oscillatory locomotion and hence, a more pelagic lifestyle. Copyright © 2013 Wiley Periodicals, Inc.

  6. Middle fossa arachnoid cyst with temporal lobe agenesis accompanying isodense subdural hematoma -a case report-

    International Nuclear Information System (INIS)

    Lee, Kyung Soo; Choi, Hyung Sik; Kim, Myung Joon; Yang, Seoung Oh; Kim, Chang Jin

    1987-01-01

    Cysts overlying the temporal lobes have been well described in literature. These are often associated with agenesis of the temporal lobes, and of major neurosurgical interest due to their frequent association with subdural hematoma, a combination that is rarely seen with cysts in other regions. Full features of plain, angiographic, and CT findings of arachnoid cyst with temporal lobe agenesis accompanying isodense subdural hematoma are presented, being very rare in radiologic literature

  7. A bivariate approach to the widening of the frontal lobes in the genus Homo.

    Science.gov (United States)

    Bruner, Emiliano; Holloway, Ralph L

    2010-02-01

    Within the genus Homo, the most encephalized taxa (Neandertals and modern humans) show relatively wider frontal lobes than either Homo erectus or australopithecines. The present analysis considers whether these changes are associated with a single size-based or allometric pattern (positive allometry of the width of the anterior endocranial fossa) or with a more specific and non-allometric pattern. The relationship between hemispheric length, maximum endocranial width, and frontal width at Broca's area was investigated in extant and extinct humans. Our results do not support positive allometry for the frontal lobe's width in relation to the main endocranial diameters within modern humans (Homo sapiens). Also, the correlation between frontal width and hemispheric length is lower than the correlation between frontal width and parieto-temporal width. When compared with the australopithecines, the genus Homo could have experienced a non-allometric widening of the brain at the temporo-parietal areas, which is most evident in Neandertals. Modern humans and Neandertals also display a non-allometric widening of the anterior endocranial fossa at the Broca's cap when compared with early hominids, again more prominent in the latter group. Taking into account the contrast between the intra-specific patterns and the between-species differences, the relative widening of the anterior fossa can be interpreted as a definite evolutionary character instead of a passive consequence of brain size increase. This expansion is most likely associated with correspondent increments of the underlying neural mass, or at least with a geometrical reallocation of the frontal cortical volumes. Although different structural changes of the cranial architecture can be related to such variations, the widening of the frontal areas is nonetheless particularly interesting when some neural functions (like language or working memory, decision processing, etc.) and related fronto-parietal cortico

  8. Obsessions appear after the removal a brain tumor in the right frontal lobe.

    Science.gov (United States)

    Liu, Jie; Zhang, Xinhua; Liu, Jihua

    2014-01-01

    A series of case reports and neuroimaging research points to the underlying neuropathological substrate for obsessive-compulsive disorder (OCD) and the underlying associations between OCD and areas of the frontal lobe. We report a patient wherein the onset of OCD occurred after resection of meningioma of the right frontal lobe and who was treated successfully with paroxetine hydrochloride. We suggest that the onset of secondary (organic) OCD is associated with the frontal lobe, and we propose that the origin of obsessions is located in the right frontal lobe. Copyright © 2014 Elsevier Inc. All rights reserved.

  9. DUAL POLARIZATION ANTENNA ARRAY WITH VERY LOW CROSS POLARIZATION AND LOW SIDE LOBES

    DEFF Research Database (Denmark)

    1997-01-01

    formation of grating lobes are inhibited in selected directions of the radiation and cross polarization within the main lobe is suppressed at least 30 dB below the main lobe peak value. According to a preferred embodiment of the invention, the antenna elements of the antenna array comprise probe-fed patches......The present invention relates to an antenna array adapted to radiate or receive electromagnetic waves of one or two polarizations with very low cross polarization and low side lobes. An antenna array comprising many antenna elements, e.g. more than ten antenna elements, is provided in which...

  10. The Frontal Lobe Score: part II: evaluation of its clinical validity.

    Science.gov (United States)

    Wildgruber, D; Kischka, U; Fassbender, K; Ettlin, T M

    2000-06-01

    To evaluate the ability of the Frontal Lobe Score (FLS) to differentiate patients with frontal lobe lesions from those with nonfrontal lesions and normal controls. In a prospective, blind setup, the sensitivity and specificity of the Frontal Lobe Score was compared with the Wisconsin Card Sorting Test (WCST) and the Stroop Test. A sample of 108 subjects (26 patients with cerebral lesions confined to the frontal lobes, 28 patients with cerebral lesions without involvement of the frontal lobes, 31 patients with mixed frontal/nonfrontal lesions, 23 controls without cerebral lesions) was examined. Frontal Lobe Score, Wisconsin Card Sorting Test, Stroop Test. The Frontal Lobe Score detected pure frontal lesions with a sensitivity of 92.3%. It discriminated patients with frontal lesions from normal controls with a specificity of 100%; differentiation from patients with nonfrontal lesions was obtained with a specificity of 75.0%. For the WCST, sensitivity for detection of pure frontal lesions was 65.4%, while specificity was 60.9% compared with normal controls and 53.6% compared with nonfrontal lesions. The Stroop Test showed a sensitivity of 30.8%, a specificity compared with normal controls of 95.7% and compared with nonfrontal lesions of 92.9%. The Frontal Lobe Score has clinical usefulness for screening of effects of frontal lobe damage superior to that of the WCST and the Stroop Test.

  11. Reactivation of medial temporal lobe and occipital lobe during the retrieval of color information: A positron emission tomography study.

    Science.gov (United States)

    Ueno, Aya; Abe, Nobuhito; Suzuki, Maki; Hirayama, Kazumi; Mori, Etsuro; Tashiro, Manabu; Itoh, Masatoshi; Fujii, Toshikatsu

    2007-02-01

    It is widely accepted that memory traces of an event include various types of information about the content of the event and about the circumstances in which the individual experienced it. However, how these various types of information are stored and later retrieved is poorly understood. One hypothesis postulates that the retrieval of specific event information reactivates regions that were active during the encoding of this information, with the aid of binding functions of the medial temporal lobe (MTL) structures. We used positron emission tomography to identify the brain regions related to the encoding and retrieval of color information. Specifically, we assessed whether overlapping activity was found in both the MTL structures and color-related cortical regions during the encoding and retrieval of color information attached with meaningless shapes. During the study, subjects were asked to encode colored (red or green) and achromatic random shapes. At subsequent testing, subjects were presented with only achromatic shapes, which had been presented with or without colors during encoding, and were engaged in retrieval tasks of shapes and colors. Overlapping activity was found in the MTL and occipital lobe (the lingual and inferior occipital gyri) in the right hemisphere during the encoding and retrieval of meaningless shapes with color information compared with those without color information. Although there are some limitations to be considered, the present findings seem to support the view that the retrieval of specific event information is associated with reactivation of both the MTL structures and the regions involved during encoding of the information.

  12. Clinical characteristics of patients with benign nonlesional temporal lobe epilepsy

    Directory of Open Access Journals (Sweden)

    Kim J

    2016-07-01

    Full Text Available Jiyeon Kim,1 Seong Hoon Kim,2 Sung Chul Lim,2 Woojun Kim,2 Young-Min Shon3 1Department of Neurology, Korea University Ansan Hospital, College of Medicine, Korea University, Ansan, 2Department of Neurology, Catholic Neuroscience Institute, College of Medicine, The Catholic University of Korea, Seocho-gu, 3Department of Neurology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea Purpose: To evaluate the evolution of nonlesional temporal lobe epilepsy (TLE-NL in patients treated exclusively with antiepileptic drugs and to elucidate clinical phenotypes related to the prognosis of these patients.Methods: Clinical, radiological, and electroencephalographic (EEG findings in 84 patients with TLE-NL were reviewed. A good response group (GRG and a poor response group (PRG were defined if the duration of their seizure-free period was >1 year, or <1 year, respectively.Results: There were 46 (54.8% patients in the GRG and 38 (45.2% patients in the PRG. The number of antiepileptic drugs administered was significantly lower in the GRG than that in the PRG (1.3±0.8 vs 2.8±1.0, respectively; P<0.05. The GRG had a significantly older age of onset than the PRG and a lower occurrence of initial precipitating events, such as febrile seizures, central nervous system infection, and head trauma (P<0.05. The prevalence of EEG abnormality, presence of aura, generalized seizures, and automatism was less frequently observed in the GRG (P<0.05. Multivariate analysis showed that the presence of automatism and initial precipitating events were significantly associated with a poor prognosis (P<0.05.Conclusion: In contrast to the commonly assumed intractability of TLE, we found that more than 54% of patients with TLE-NL achieved a long seizure-free period. Older age at onset of TLE-NL was associated with a better prognosis. However, the presence of automatism and initial precipitating events were related to a poor prognosis. Future prospective

  13. Interictal brain SPECT in patients with medically refractory temporal lobe epilepsy; SPECT cerebral interictal em pacientes com epilepsia do lobo temporal de dificil controle

    Energy Technology Data Exchange (ETDEWEB)

    Andraus, Maria Emilia Cosenza

    2000-06-01

    The brain single photon emission computed tomography (SPECT) is s functional neuroimaging method that can detect localized changes in cerebral blood flow. The temporal lobe epilepsy (TLE) is the most common epileptic syndrome in adults, and more than 50% are medically refractory. The SPECT can contribute to investigation of epileptogenic focus and is one of the methods of pre-surgical evaluation of these patients. (author)

  14. Simultaneous Optical and Electrical Recording of Single Gramicidin Channels

    OpenAIRE

    Borisenko, V.; Lougheed, T.; Hesse, J.; Füreder-Kitzmüller, E.; Fertig, N.; Behrends, J.C.; Woolley, G.A.; Schütz, G.J.

    2003-01-01

    We report here an approach for simultaneous fluorescence imaging and electrical recording of single ion channels in planar bilayer membranes. As a test case, fluorescently labeled (Cy3 and Cy5) gramicidin derivatives were imaged at the single-molecule level using far-field illumination and cooled CCD camera detection. Gramicidin monomers were observed to diffuse in the plane of the membrane with a diffusion coefficient of 3.3 × 10−8 cm2s−1. Simultaneous electrical recording detected gramicidi...

  15. Effect of chemical stimulation of the medial frontal lobe on the micturition reflex in rats.

    Science.gov (United States)

    Nishijima, Saori; Sugaya, Kimio; Kadekawa, Katsumi; Ashitomi, Katsuhiro; Yamamoto, Hideyuki

    2012-03-01

    We assessed the influence of the medial frontal lobe on micturition after chemical stimulation. We also examined the relation between the medial frontal lobe and the rostral pontine reticular formation, which has a strong inhibitory effect on micturition. A total of 35 female rats underwent continuous cystometry. Bladder activity changes were examined after physiological saline, glutamate, the glutamate receptor antagonist MK-801, noradrenaline or the adrenergic α-1 receptor antagonist naftopidil was injected in the medial frontal lobe. When glutamate was injected in the medial frontal lobe, MK-801 was also injected in the rostral pontine reticular formation. Glutamate injection in the medial frontal lobe prolonged the interval between bladder contractions while injection of the glutamate antagonist MK-801 shortened the interval. Glutamate injection in the medial frontal lobe just after MK-801 injection in the ipsilateral rostral pontine reticular formation also prolonged the interval between bladder contractions. However, after prior injection of MK-801 in the bilateral rostral pontine reticular formation glutamate injection in the medial frontal lobe did not influence cystometric parameters. Noradrenaline injection in the medial frontal lobe shortened the interval between bladder contractions while injection of its antagonist naftopidil prolonged the interval. Medial frontal lobe neurons excited by glutamate inhibited the micturition reflex via activation of the rostral pontine reticular formation by glutamatergic projection while medial frontal lobe neurons excited by noradrenaline facilitated the micturition reflex. Thus, the medial frontal lobe may be an important integration center for the initiation of micturition and urine storage mechanisms. Copyright © 2012 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

  16. Simulations of far-field optical beam quality influenced by the thermal distortion of the secondary mirror for high-power laser system

    Science.gov (United States)

    Guo, Ruhai; Chen, Ning; Zhuang, Xinyu; Wang, Bing

    2015-02-01

    In order to research the influence on the beam quality due to thermal deformation of the secondary mirror in the high power laser system, the theoretical simulation study is performed. Firstly, three typical laser power 10kW, 50kW and 100kW with the wavelength 1.064μm are selected to analyze thermal deformation of mirror through the finite element analyze of thermodynamics instantaneous method. Then the wavefront aberration can be calculated by ray-tracing theory. Finally, focus spot radius,beam quality (BQ) of far-filed beam can be calculated and comparably analyzed by Fresnel diffraction integration. The simulation results show that with the increasing laser power, the optical aberration of beam director gets worse, the far-field optical beam quality decrease, which makes the laser focus spot broadening and the peak optical intensity of center decreasing dramatically. Comparing the clamping ring and the three-point clamping, the former is better than the latter because the former only induces the rotation symmetric deformation and the latter introduces additional astigmatism. The far-field optical beam quality can be improved partly by simply adjusting the distance between the main mirror and the secondary mirror. But the far-field power density is still the one tenth as that without the heat distortion of secondary mirror. These results can also provide the reference to the thermal aberration analyze for high power laser system and can be applied to the field of laser communication system and laser weapon etc.

  17. Complex Partial Epilepsy Associated with Temporal Lobe Developmental Venous Anomaly.

    Science.gov (United States)

    Sohail, Amna; Xiong, Zhengming; Qureshi, Mushtaq H; Qureshi, Adnan I

    2015-05-01

    Developmental venous anomalies (DVA) are found incidentally but sometimes patients with these anomalies present with varying degrees of neurologic manifestations. We report a patient with early onset complex partial epilepsy and associated DVA and discuss the natural history, neuroimaging and clinical characteristics, and management. A 21-year-old man presented with a history of complex partial epilepsy with secondary generalization which started at the age of 4 years. An electroencephalogram (EEG) was performed which demonstrated spike and wave discharges predominantly in the left frontotemporal region. A magnetic resonance imaging (MRI) was performed which demonstrated a linear flow void suggestive of a DVA. The angiogram demonstrated DVA that connected with the left transverse venous sinus and an anastomotic vein between the straight sinus and the transverse venous sinus traversing the brain parenchyma. He was started on carbamezipine for the treatment of complex partial seizures. Temporal lobe DVA may be associated with complex partial seizures and can be diagnosed by MRI and angiographic findings.

  18. Memory in children with symptomatic temporal lobe epilepsy

    Directory of Open Access Journals (Sweden)

    Catarina A. Guimarães

    2014-03-01

    Full Text Available In children with temporal lobe epilepsy (TLE, memory deficit is not so well understood as it is in adults. The aim of this study was to identify and describe memory deficits in children with symptomatic TLE, and to verify the influence of epilepsy variables on memory. We evaluated 25 children with TLE diagnosed on clinical, EEG and MRI findings. Twenty-five normal children were compared with the patients. All children underwent a neuropsychological assessment to estimate intellectual level, attention, visual perception, handedness, and memory processes (verbal and visual: short-term memory, learning, and delayed recall. The results allowed us to conclude: besides memory deficits, other neuropsychological disturbances may be found in children with TLE such as attention, even in the absence of overall cognitive deficit; the earlier onset of epilepsy, the worse verbal stimuli storage; mesial lesions correlate with impairment in memory storage stage while neocortical temporal lesions correlate with retrieval deficits.

  19. Impaired executive functions in experimental model of temporal lobe epilepsy

    Directory of Open Access Journals (Sweden)

    Fabiane Ochai Ramos

    2016-06-01

    Full Text Available ABSTRACT Objective The present study aimed to investigate cognitive and behavioural changes consistent with attention deficit hyperactivity disorder (ADHD -like behavior in male Wistar rats with temporal lobe epilepsy (TLE. Method Male Wistar rats at 25 day of age were submitted to animal model of TLE by pilocarpine injection (350 mg/kg, ip and a control group received saline 0.9%. The animals were continuously video monitored up to the end of experiments. The behavioural tests (open field, elevated plus maze and operant conditioning box started from 60 days postnatal. Results Animals with TLE exhibited elevated locomotor activity, reduced level of anxiety-related behavior, impulsivity and impaired visuospatial working memory. Conclusion Taken as a whole, we concluded that animals with TLE exhibited some cognitive and behavioural changes consistent with ADHD-like behavior.

  20. Nocturnal frontal lobe epilepsy presenting as excessive daytime sleepiness

    Directory of Open Access Journals (Sweden)

    Jocelyn Y Cheng

    2013-01-01

    Full Text Available Excessive daytime sleepiness (EDS is common in the general population. Etiologies include insufficient sleep and primary sleep disorders. Due to its high prevalence, physicians often overlook EDS as a significant problem. However, EDS may also be the presenting symptom of seizures, in particular Nocturnal Frontal Lobe Epilepsy (NFLE. Due to the clinical similarity between the nocturnal behaviors of NFLE and parasomnias, and poor patient-related history, NFLE remains a challenging diagnosis. We report the case of a patient with NFLE who presented with a primary complaint of EDS, and discuss the differential diagnosis and evaluation of patients with EDS associated with nocturnal behaviors. In the context of a patient presenting with EDS and stereotyped nocturnal events, clinical suspicion should be high for NFLE.

  1. Space to ground sequential lobe tracking of aircraft

    Science.gov (United States)

    Shannon, P. D.; Kwon, D. W.; Polites, M.

    Growing demand for satellite communications capability coupled with shrinking government budgets, has spurred acquisition and repurposing of commercial satellite systems for government missions. One subset of these satellites provides high bandwidth communication with aerial vehicles from geosynchronous orbit. Automated tracking by these satellites of aerial vehicles improves link margin, but is not a typical function of commercial product lines. Additional tracking hardware and flight software development are required to give these commercial products tracking capability. This leads to an inefficient design from a cost and mass standpoint for a large number of slow flying aerial vehicles. Therefore, a need was identified to design a low cost tracking system that minimizes tracking specific spacecraft hardware and flight software development. This paper outlines a sequential lobe tracking system to auto track aerial vehicles and analyzes the algorithm's accuracy and sensitivity in tracking aerial vehicles using their pre-existing uplink signal. The tracking scheme consists of a satellite based RF power meter, automated ground based control of antenna pointing, and ground based processing of the tracking telemetry. The aerial vehicle was modeled as a high altitude, relatively slow moving Ka-band aircraft. To identify and evaluate a feasible design, a MATLAB model was developed to simulate an aerial vehicle, the vehicle's primary uplink signal and its variance, communication and processing latency in the design, and tracking telemetry processing. In addition, the effect on the spacecraft antenna actuators was modeled. The primary output of the model is tracking accuracy and Monte Carlo simulations were used to determine 1, 2, and 3 sigma results. Overall, this paper demonstrates the viability of a sequential lobe scheme with ground based processing as a low cost alternative for Space-to-Ground tracking of slow flying aerial vehicles.

  2. Altered synchrony and loss of consciousness during frontal lobe seizures.

    Science.gov (United States)

    Bonini, Francesca; Lambert, Isabelle; Wendling, Fabrice; McGonigal, Aileen; Bartolomei, Fabrice

    2016-02-01

    Loss of consciousness (LOC) in frontal lobe epilepsy (FLE) has been rarely specifically studied until now. In this study we evaluated the LOC in a population of patients with FLE and studied the relationship between changes in synchrony and degree of LOC. 24 patients undergoing stereoelectroencephalography (SEEG) during pre-surgical evaluation of FLE were studied. The LOC intensity was scored using the Consciousness Seizure Scale (CSS). For each studied seizure (n=52), interdependencies between signals recorded from 5 brain regions were estimated as a function of time by using non-linear regression analysis (h(2) coefficient). Seizures were divided into 3 groups according to the CSS scale: group A (no LOC) with a score ⩽2, group B (intermediate or partial LOC) with a score ranging from 3 to 5, and group C (maximal LOC) with a score ⩾6. The majority of seizures in FLE patients disclosed significant LOC, particularly for patients with prefrontal lobe seizures. Mean correlation values were significantly different between groups A and C (p<0.001), the maximal values of synchrony being observed in group C. Differences were significant for interaction affecting the external prefrontal cortex (p=0.004) (p=0.01) and the parietal cortex. In addition, a significant correlation was found between CSS scores and correlations values (h(2)) of the prefrontal and the parietal region but not with the premotor cortex. This study indicates that in FLE, prefrontal seizures frequently alter consciousness. As in other focal seizures, LOC appears to be related to changes in synchrony in prefrontal and parietal associative cortices. LOC in FLE is frequent and as in other focal epilepsies is related to an alteration of prefrontal-parietal network. Copyright © 2015 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

  3. Mesial temporal lobe epilepsy diminishes functional connectivity during emotion perception.

    Science.gov (United States)

    Steiger, Bettina K; Muller, Angela M; Spirig, Esther; Toller, Gianina; Jokeit, Hennric

    2017-08-01

    Unilateral mesial temporal lobe epilepsy (MTLE) has been associated with impaired recognition of emotional facial expressions. Correspondingly, imaging studies showed decreased activity of the amygdala and cortical face processing regions in response to emotional faces. However, functional connectivity among regions involved in emotion perception has not been studied so far. To address this, we examined intrinsic functional connectivity (FC) modulated by the perception of dynamic fearful faces among the amygdala and limbic, frontal, temporal and brainstem regions. Regions of interest were identified in an activation analysis by presenting a block-design with dynamic fearful faces and dynamic landscapes to 15 healthy individuals. This led to 10 predominately right-hemispheric regions. Functional connectivity between these regions during the perception of fearful faces was examined in drug-refractory patients with left- (n=16) or right-sided (n=17) MTLE, epilepsy patients with extratemporal seizure onset (n=15) and a second group of 15 healthy controls. Healthy controls showed a widespread functional network modulated by the perception of fearful faces that encompassed bilateral amygdalae, limbic, cortical, subcortical and brainstem regions. In patients with left MTLE, a downsized network of frontal and temporal regions centered on the right amygdala was present. Patients with right MTLE showed almost no significant functional connectivity. A maintained network in the epilepsy control group indicates that findings in mesial temporal lobe epilepsy could not be explained by clinical factors such as seizures and antiepileptic medication. Functional networks underlying facial emotion perception are considerably changed in left and right MTLE. Alterations are present for both hemispheres in either MTLE group, but are more pronounced in right MTLE. Disruption of the functional network architecture possibly contributes to deficits in facial emotion recognition frequently

  4. A review of sorption of radionuclides under the near- and far-field conditions of an underground radioactive waste repository. Pt. 2

    International Nuclear Information System (INIS)

    Berry, J.A.

    1992-01-01

    This report, a bibliography, has been prepared, presenting work carried out world-wide since 1970 on the sorption of radionuclides under near- and far-field conditions. Work has been included where the results are relevant to the disposal of low- and intermediate-level radioactive waste in a cementitious repository in the UK. The bibliography has been prepared using the INIS database and includes eight hundred references, listed both by subject and by country. In addition to these indexes, full abstracts are presented in reverse chronological order. A brief description of the relevance and measurement of sorption parameters is included. (author)

  5. Characteristics of X-point lobe structures in single-null discharges on MAST

    Czech Academy of Sciences Publication Activity Database

    Harrison, J.R.; Kirk, A.; Chapman, I.T.; Cahyna, Pavel; Liu, Y.; Nardon, E.; Thornton, A.J.

    2014-01-01

    Roč. 54, č. 6 (2014), 064015-064015 ISSN 0029-5515 R&D Projects: GA ČR GAP205/11/2341 Institutional support: RVO:61389021 Keywords : tokamak * MAST * X-point * resonant magnetic perturbation Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 3.062, year: 2014 http://iopscience.iop.org/0029-5515/54/6/064015/pdf/0029-5515_54_6_064015.pdf

  6. Differential Growth in Periclinal and Anticlinal Walls during Lobe Formation in Arabidopsis Cotyledon Pavement Cells.

    Science.gov (United States)

    Armour, William J; Barton, Deborah A; Law, Andrew M K; Overall, Robyn L

    2015-09-01

    Lobe development in the epidermal pavement cells of Arabidopsis thaliana cotyledons and leaves is thought to take place via tip-like growth on the concave side of lobes driven by localized concentrations of actin filaments and associated proteins, with a predicted role for cortical microtubules in establishing the direction of restricted growth at the convex side. We used homologous landmarks fixed to the outer walls of pavement cells and thin-plate spline analysis to demonstrate that lobes form by differential growth of both the anticlinal and periclinal walls. Most lobes formed within the first 24 h of the cotyledons unfurling, during the period of rapid cell expansion. Cortical microtubules adjacent to the periclinal wall were persistently enriched at the convex side of lobes during development where growth was anisotropic and were less concentrated or absent at the concave side where growth was promoted. Alternating microtubule-enriched and microtubule-free zones at the periclinal wall in neighboring cells predicted sites of new lobes. There was no particular arrangement of cortical actin filaments that could predict where lobes would form. However, drug studies demonstrate that both filamentous actin and microtubules are required for lobe formation. © 2015 American Society of Plant Biologists. All rights reserved.

  7. Changes in neuropsychological functioning following temporal lobectomy in patients with temporal lobe epilepsy

    NARCIS (Netherlands)

    Shin, M.S.; Lee, S.; Seol, S.H.; Lim, Y.J.; Park, E.H.; Sergeant, J.A.; Chung, C.

    2009-01-01

    Purpose: This study was conducted to evaluate the changes in neuropsychological functioning in patients with temporal lobe epilepsy (TLE) after temporal lobe resection. Methods: Fifty-four TLE patients were evaluated before and after surgery using comprehensive neuropsychological tests to assess

  8. On the vorticity characteristics of lobe-forced mixer at different configurations

    NARCIS (Netherlands)

    mao, R.; Yu, S.C.M.; Zhou, T.; Chua, L.P.

    2009-01-01

    Lobe-forced mixer is one typical example of the passive flow controllers owing to its corrugated trailing edge. Besides the spanwise Kelvin–Helmholtz vortex shedding, streamwise vortices are also generated within its mixing layer. The geometrical configuration of the lobe significantly affects these

  9. Pleomorphic adenoma in the palpebral lobe of the lacrimal gland misdiagnosed as chalazion.

    Science.gov (United States)

    Ramlee, Nor'Aini; Ramli, Noramazlan; Tajudin, Liza-Sharmini Ahmad

    2007-06-01

    We reported a case of pleomorphic adenoma of the lacrimal gland involving the palpebral lobe in young teenage girl of Asian origin. The presentation at young age group is rare, which initially misdiagnosed as a large chalazion. The benign tumor with its intact pseudocapsule was removed through lateral orbitotomy together with the suspicious looking orbital lobe.

  10. First reported case of unilateral Graves' disease in the left lobe of a bilobar thyroid gland.

    Science.gov (United States)

    Chen, Louis C; Green, Jennifer B

    2011-06-01

    Unilateral Graves' disease is a rare disease variant that can occur in a bilobar thyroid gland. We report the first documented case of unilateral Graves' disease in the left lobe of a bilobar thyroid gland and review the pertinent literature. A 48-year-old man presented in June 2010 with thyrotoxicosis. I-131 radioisotope uptake was elevated at 33.4%, and scintigraphy revealed that uptake of the radioisotope was uniformly increased in the left lobe of the thyroid gland. Ultrasonography of the thyroid gland revealed a non-nodular, enlarged, and heterogeneous left lobe; Doppler investigation of the lobe showed hypervascularity classically seen in Graves' disease. The right lobe of the thyroid, on the other hand, appeared homogeneous and hypovascular on ultrasonography. Thyroid-stimulating immunoglobulin was significantly elevated at 191% (reference range disease was the most likely diagnosis. As has occasionally been described in the literature, unilateral involvement of the thyroid gland is a rare presentation of Graves' disease. Pre-existing functional or structural differences (either congenital or acquired) between the two lobes may contribute to this rare presentation. To our knowledge, this is the first reported case of unilateral Graves' disease presenting in the left lobe of a bilobar thyroid gland. Although the pathophysiology of unilateral Graves's disease has not been clearly elucidated, clinicians should be aware that Graves' disease can present unilaterally in either lobe of the thyroid gland.

  11. Frontal and Lateral Submarine Lobe Fringes: Comparing Sedimentary Facies, Architecture and Flow Processes

    NARCIS (Netherlands)

    Spychala, Yvonne T.; Hodgson, David M.; Prélat, Amandine; Kane, Ian A.; Flint, Stephen S.; Mountney, Nigel P.

    2017-01-01

    Submarine lobe-fringe deposits form heterolithic successions that may include a high proportion of hybrid beds. The identification of lobe-fringe successions aids interpretation of paleogeographic setting and the degree of basin confinement. Here, for the first time, the sedimentological and

  12. Diffusion tensor imaging (DTI) in dementia patients with frontal lobe symptoms

    Energy Technology Data Exchange (ETDEWEB)

    Naik, Mala; Geitung, Jonn-Terje (Dept. of Geriatrics, Haraldsplass Deaconess Hospital, Bergen (Norway)), e-mail: mnaik@broadpark.no; Lundervold, Arvid (Dept. of Biomedicine, Univ. of Bergen (Norway)); Nygaard, Harald (Olaviken Hospital (Norway))

    2010-07-15

    Background: Diffusion tensor imaging (DTI) is a recent MRI technique demonstrating white matter tracts in the brain. Dementia is a neurodegenerative disease and this method has been used to demonstrate the loss of axonal fibers and myelin and decrease of fiber density in this condition. Purpose: To study a possible correlation between frontal lobe symptoms in patients with dementia and reduced fractional anisotropy (FA) in white matter/fascicles in the frontal lobes. Material and Methods: The study included 23 patients with dementia and frontal lobe symptoms and 20 controls (10 Alzheimer patients without frontal lobe symptoms and 10 normal controls). Clinical tests and MRI with DTI were performed. FA in subcortical white matter of both the frontal lobes was analyzed and correlated with clinical frontal score tests. Results: We found a significant correlation between frontal score results and reduction in FA in the frontal lobes. The FA in the study group was significantly lower than the FA in the control group. Conclusion: The present study reveals that there is a probable correlation between the extent of frontal lobe symptoms and FA in fascicles/white matter tissue in the frontal lobes

  13. Mother and daughter with adolescent-onset severe frontal lobe dysfunction and epilepsy

    Science.gov (United States)

    dos Passos, Giordani Rodrigues; Fernández, Alonso Cuadrado; Vasques, Adriana Machado; Martins, William Alves; Palmini, André

    2016-01-01

    ABSTRACT Familial cases of early-onset prominent frontal lobe dysfunction associated with epilepsy have not been reported to date. We report a mother and her only daughter with incapacitating behavioral manifestations of frontal lobe dysfunction and epilepsy of variable severity. The possibility of a hitherto undescribed genetic condition is discussed. PMID:29213461

  14. Frontal Lobe Involvement in a Task of Time-Based Prospective Memory

    Science.gov (United States)

    McFarland, Craig P.; Glisky, Elizabeth L.

    2009-01-01

    Time-based prospective memory (PM) has been found to be negatively affected by aging, possibly as a result of declining frontal lobe (FL) function. Despite a clear retrospective component to PM tasks, the medial temporal lobes (MTL) are thought to play only a secondary role in successful task completion. The present study investigated the role of…

  15. Hypothesis on two different functionalities co-existing in frontal lobe of human brains.

    Science.gov (United States)

    Wang, Jue

    2013-09-01

    Human frontal lobe is a key area from where our cognition, memory and emotion display or function. In medical case study, there are patients with social dysfunctions, lack of passion or emotion as result of their frontal lobe damage caused by pathological changes, traumatic damage, and brain tumor remove operations. The syndrome of frontal lobe damage remains at large unanswered medically. From early stage of pregnancy, there exists lobe layers, nerve combine, and neurons synaptic, indicating a completion of growth of functionality inside frontal lobe. However, this completion of growth does not match the growth of human intelligence. Human infants only start and complete their cognition and memory functionality one full year after their birth which is marked by huge amount of neurons synaptic inside their frontal lobe, which is not part of a continual growth of originally developed functions. By reasoning on pathological changes of frontal lobe, a hypothesis was established that two individually functional mechanisms co-existed inside one frontal lobe. This neuron system is particularly for human beings. Copyright © 2013 Elsevier Ltd. All rights reserved.

  16. The relationship of medial temporal lobe epilepsy with the declarative memory system

    Directory of Open Access Journals (Sweden)

    Halász Péter

    2016-12-01

    Full Text Available Introduction. Medial temporal lobe of epilepsy (MTLE is considered as local/regional epilepsy. However, as was discussed in Part I of this review (Halász, 2016a there is more evidence regarding the involvement of both temporal lobes so as to consider MTLE as one of the typical bilateral system epilepsies.

  17. Floating of the lobes of mosquito (Aedes togoi) larva for respiration.

    Science.gov (United States)

    Lee, Seung Chul; Kim, Jun Ho; Lee, Sang Joon

    2017-02-20

    Mosquito (Aedes togoi) larva has to float its siphon on the water surface to breathe air. To elucidate the floating mechanism of the siphon, morphological structures, especially the flap-like lobes and spiracle of the siphon, were observed. Wettability and dynamic behavior of the lobes on the water surface were also experimentally examined. The lobes formed a hollow cone shape under water and expanded on the water surface. The spiracle was located at the base of the cone. The lobes exhibited hydrophobic wettability. During floating process, the lobes were spread into a triangular shape in apical view, and the spiracle was exposed to air. When they were submerged in water, the lobes were folded into a cone shape to seal the spiracle and protect it from water penetration. These dynamic processes occurred at the water surface. In this study, the floating mechanism of the lobes for respiration was described based on the cross-sectional morphology of the lobes with the pressure induced by surface tension and the hydrostatic pressure proportional to depth. This study would be helpful in elucidating the behavior of mosquito larvae near the water surface and may facilitate the formulation of methods to control mosquito larvae.

  18. Intermittent torsion of accessory hepatic lobe: An unusual cause of recurrent right upper quadrant pain

    Directory of Open Access Journals (Sweden)

    Jambhekar Kedar

    2010-01-01

    Full Text Available An accessory lobe of the liver is a rare congenital anomaly that can undergo torsion and present as an acute surgical emergency. It is rarely diagnosed preoperatively. We report the preoperative utility of CT scan and MRI in the diagnosis and surgical planning of a case of intermittent accessory hepatic lobe torsion.

  19. The Azygous Lobe of the Lung: in the Case of Lung Cancer.

    Science.gov (United States)

    Darlong, L M; Ram, Dharma; Sharma, Ashwani; Sharma, Anil Kumar; Iqbal, Sayed Assif; Nagar, Anand; Hazarika, Dibyamohan

    2017-06-01

    The azygous lobe of the lung is an uncommon developmental anomaly. Its surgical importance is hardly being described in literature. Here, we are presenting a case of lung cancer with incidental azygous lobe, with its surgical relevance during lung cancer surgery.

  20. Visuo-spatial construction in patients with frontal and parietal lobe lesions

    Directory of Open Access Journals (Sweden)

    Himani Kashyap

    2011-04-01

    Full Text Available Visuospatial construction, traditionally viewed as a putative parietal function, also requires sustained attention, planning, organization strategies and error correction, and hence frontal lobe mediation. The relative contributions of the frontal and parietal lobes are poorly understood. To examine the contributions of parietal, frontal lobes, as well as right and left cerebral hemispheres to visuospatial construction. The Stick Construction Test for two-dimensional construction and the Block Construction Test for three-dimensional construction were administered pre-surgically to patients with lesions in the parietal lobe (n =9 and the frontal lobe (n=11, along with normal control subjects (n =20 matched to the patients on age (+/- 3 years, gender, education (+/- 3 years and handedness. The patients were significantly slower than the controls on both two-dimensional and three-dimensional tests. Patients with parietal lesions were slower than those with frontal lesions on the test of three-dimensional construction. Within each lobe patients with right and left sided lesions did not differ significantly. It appears that tests of three-dimensional construction might be most sensitive to visuospatial construction deficits. Visuospatial construction involves the mediation of both frontal and parietal lobes. The function does not appear to be lateralized. The networks arising from the parieto-occipital areas and projecting to the frontal cortices (e.g., occipito-frontal fasciculus may be the basis of the mediation of both lobes in visuospatial construction. The present findings need replication from studies with larger sample sizes.

  1. Agenesis of the left hepatic lobe undergoing laparoscopic hepatectomy for hepatocellular carcinoma: a case report.

    Science.gov (United States)

    Matsushita, Katsunori; Gotoh, Kunihito; Eguchi, Hidetoshi; Iwagami, Yoshihumi; Yamada, Daisaku; Asaoka, Tadafumi; Noda, Takehiro; Wada, Hiroshi; Kawamoto, Koichi; Doki, Yuichiro; Mori, Masaki

    2017-12-01

    Agenesis of the left hepatic lobe is a rare anomaly. It is defined as the absence of liver tissue to the left of the gallbladder fossa. Additionally, agenesis of the left hepatic lobe accompanied by hepatocellular carcinoma is quite rare. We experienced the case of a patient with agenesis of the left hepatic lobe, undergoing laparoscopic hepatectomy for HCC. A 79-year-old man was referred to our department with epigastralgia. Abdominal computed tomography revealed agenesis of the left hepatic lobe, accompanied by hepatocellular carcinoma in segments 7 and 8. He underwent laparoscopic partial hepatectomy of segments 7 and 8. The operative findings revealed complete agenesis of the liver to the left of the falciform ligament. The patient had a favorable clinical course without liver dysfunction or any complications. We experienced a case with agenesis of the left hepatic lobe undergoing laparoscopic hepatectomy for HCC. Awareness of such anomaly is important for surgeons to avoid postoperative complications.

  2. Image processing analysis of vortex dynamics of lobed jets from three-dimensional diffusers

    International Nuclear Information System (INIS)

    Nastase, Ilinca; Meslem, Amina; El Hassan, Mouhammad

    2011-01-01

    The passive control of jet flows with the aim to enhance mixing and entrainment is of wide practical interest. Our purpose here is to develop new air diffusers for heating ventilating air conditioning systems by using lobed geometry nozzles, in order to ameliorate the users' thermal comfort. Two turbulent six-lobed air jets, issued from a lobed tubular nozzle and an innovative hemispherical lobed nozzle, were studied experimentally. It was shown that the proposed innovative concept of a lobed jet, which can be easily integrated in air diffusion devices, is very efficient regarding induction capability. A vortical dynamics analysis for the two jets is performed using a new method of image processing, namely dynamic mode decomposition. A validation of this method is also proposed suggesting that the dynamical mode decomposition (DMD) image processing method succeeds in capturing the most dominant frequencies of the flow dynamics, which in our case are related to the quite special dynamics of the Kelvin–Helmholtz vortices.

  3. Contrast-enhanced ultrasonographic findings in three dogs with lung lobe torsion.

    Science.gov (United States)

    Caivano, Domenico; Birettoni, Francesco; Bufalari, Antonello; De Monte, Valentina; Angeli, Giovanni; Giorgi, Maria Elena; Patata, Valentina; Porciello, Francesco

    2016-03-01

    Lung lobe torsion is rare but life-threatening condition in the dog. Thoracic radiographs and conventional ultrasonography cannot be conclusive for the diagnosis, and computed tomography is useful but is limited by cost and availability. This report describes the findings of contrast-enhanced ultrasonography in 3 dogs with lung lobe torsion. Contrast-enhanced ultrasonography showed the absence or reduction of pulmonary vascularization secondary to twisting of the lung lobe around its bronchovascular pedicle in all three dogs. Moreover, contrast-enhanced ultrasonography distinguished partial pulmonary atelectasis from a lung lobe torsion. These preliminary results suggest that contrast-enhanced ultrasonography can improve the accuracy of conventional ultrasonography for detection of pulmonary blood flow compromise in dogs with lung lobe torsion.

  4. A Prediction Algorithm for Drug Response in Patients with Mesial Temporal Lobe Epilepsy Based on Clinical and Genetic Information.

    Science.gov (United States)

    Silva-Alves, Mariana S; Secolin, Rodrigo; Carvalho, Benilton S; Yasuda, Clarissa L; Bilevicius, Elizabeth; Alvim, Marina K M; Santos, Renato O; Maurer-Morelli, Claudia V; Cendes, Fernando; Lopes-Cendes, Iscia

    2017-01-01

    Mesial temporal lobe epilepsy is the most common form of adult epilepsy in surgical series. Currently, the only characteristic used to predict poor response to clinical treatment in this syndrome is the presence of hippocampal sclerosis. Single nucleotide polymorphisms (SNPs) located in genes encoding drug transporter and metabolism proteins could influence response to therapy. Therefore, we aimed to evaluate whether combining information from clinical variables as well as SNPs in candidate genes could improve the accuracy of predicting response to drug therapy in patients with mesial temporal lobe epilepsy. For this, we divided 237 patients into two groups: 75 responsive and 162 refractory to antiepileptic drug therapy. We genotyped 119 SNPs in ABCB1, ABCC2, CYP1A1, CYP1A2, CYP1B1, CYP2C9, CYP2C19, CYP2D6, CYP2E1, CYP3A4, and CYP3A5 genes. We used 98 additional SNPs to evaluate population stratification. We assessed a first scenario using only clinical variables and a second one including SNP information. The random forests algorithm combined with leave-one-out cross-validation was used to identify the best predictive model in each scenario and compared their accuracies using the area under the curve statistic. Additionally, we built a variable importance plot to present the set of most relevant predictors on the best model. The selected best model included the presence of hippocampal sclerosis and 56 SNPs. Furthermore, including SNPs in the model improved accuracy from 0.4568 to 0.8177. Our findings suggest that adding genetic information provided by SNPs, located on drug transport and metabolism genes, can improve the accuracy for predicting which patients with mesial temporal lobe epilepsy are likely to be refractory to drug treatment, making it possible to identify patients who may benefit from epilepsy surgery sooner.

  5. Effect of far-field stresses and residual stresses incorporation in predicting fracture toughness of carbon nanotube reinforced yttria stabilized zirconia

    Science.gov (United States)

    Mahato, Neelima; Nisar, Ambreen; Mohapatra, Pratyasha; Rawat, Siddharth; Ariharan, S.; Balani, Kantesh

    2017-10-01

    Yttria-stabilized zirconia (YSZ) is a potential thermal insulating ceramic for high temperature applications (>1000 °C). YSZ reinforced with multi-walled carbon nanotubes (MWNTs) was processed via spark plasma sintering to produce dense, crack-free homogeneous sample and avoid any degradation of MWNTs when sintered using conventional routes. Despite porosity, the addition of MWNT has a profound effect in improving the damage tolerance of YSZ by allowing the retention of tetragonal phase. However, at some instances, the crack lengths in the MWNT reinforced YSZ matrices have been found to be longer than the standalone counterparts. Therefore, it becomes inappropriate to apply Anstis equation to calculate fracture toughness values. In this regard, a combined analytical cum numerical method is used to estimate the theoretical fracture toughness and quantitatively analyze the mechanics of matrix cracking in the reinforced composite matrices incorporating the effects of various factors (such as far-field stresses, volume fraction of MWNTs, change in the modulus and Poisson's ratio values along with the increase in porosity, and bridging and phase transformation mechanism) affecting the fracture toughness of YSZ-MWNT composites. The results suggest that the incorporation of far-field stresses cannot be ignored in estimating the theoretical fracture toughness of YSZ-MWNT composites.

  6. Do children with aggressive behavior have temporal lobe changes?

    International Nuclear Information System (INIS)

    Thomas, Carmen; Godberg, Michael

    2003-01-01

    Aggressive behavior and mood disorders frequently appear in childhood. There is often lack of objective data to support a specific clinical diagnosis. Ultimately it is likely that alterations in production, concentration, storage, release, reuptake and degradation of neurotransmitters such as serotonin, dopamine, acetylcholine and gamma-aminobutyric acid play key roles in the manifestations of mood disorders. We sought to determine if more gross anatomic patterns of regional brain activation in a 'baseline' state might also supply an objective means of verifying the presence of a mood disorder characterized by anger or aggressive behavior. We studied 8 patients, 3 girls and 5 boys, ages ranging from 6 to 12, referred for SPECT brain imaging with the diagnosis of an attention deficit disorder or autism. All had been reported as having temper problems on the routine questionnaire completed by the parents prior to SPECT imaging. The patients, who were not sedated, had absolute cerebral blood flow measured by the xenon 133 gas inhalation technique followed by intravenous injection of Tc-99m HMPAO with an administered dose calculated according to patient age and weight. One hour following the injection, high resolution brain SPECT imaging was performed using a Picker triple headed camera with fan beam collimators. We analyzed the brain SPECT studies using 3D volume rendered semi-transparent images with dual cut off windows of 88 percent (high) and 60-65 percent (lower value depending on the patient absolute mean cortical blood flow), as well as the traditional transverse, coronal and sagittal sections. The dual window 3D display helped demonstrate increased perfusion or activation of either or both right and left temporal lobes in all 8 of the patients. This pattern was not seen in children with similar clinical diagnoses but whose parents did not report temper problems. These preliminary findings support the proposition that an increase in perfusion to the temporal

  7. Selective attention in the honeybee optic lobes precedes behavioral choices

    Science.gov (United States)

    Paulk, Angelique C.; Stacey, Jacqueline A.; Pearson, Thomas W. J.; Taylor, Gavin J.; Moore, Richard J. D.; Srinivasan, Mandyam V.; van Swinderen, Bruno

    2014-01-01

    Attention allows animals to respond selectively to competing stimuli, enabling some stimuli to evoke a behavioral response while others are ignored. How the brain does this remains mysterious, although it is increasingly evident that even animals with the smallest brains display this capacity. For example, insects respond selectively to salient visual stimuli, but it is unknown where such selectivity occurs in the insect brain, or whether neural correlates of attention might predict the visual choices made by an insect. Here, we investigate neural correlates of visual attention in behaving honeybees (Apis mellifera). Using a closed-loop paradigm that allows tethered, walking bees to actively control visual objects in a virtual reality arena, we show that behavioral fixation increases neuronal responses to flickering, frequency-tagged stimuli. Attention-like effects were reduced in the optic lobes during replay of the same visual sequences, when bees were not able to control the visual displays. When bees were presented with competing frequency-tagged visual stimuli, selectivity in the medulla (an optic ganglion) preceded behavioral selection of a stimulus, suggesting that modulation of early visual processing centers precedes eventual behavioral choices made by these insects. PMID:24639490

  8. Dissociated multimodal hubs and seizures in temporal lobe epilepsy.

    Science.gov (United States)

    Douw, Linda; DeSalvo, Matthew N; Tanaka, Naoaki; Cole, Andrew J; Liu, Hesheng; Reinsberger, Claus; Stufflebeam, Steven M

    2015-04-01

    Brain connectivity at rest is altered in temporal lobe epilepsy (TLE), particularly in "hub" areas such as the posterior default mode network (DMN). Although both functional and anatomical connectivity are disturbed in TLE, the relationships between measures as well as to seizure frequency remain unclear. We aim to clarify these associations using connectivity measures specifically sensitive to hubs. Connectivity between 1000 cortical surface parcels was determined in 49 TLE patients and 23 controls with diffusion and resting-state functional magnetic resonance imaging. Two types of hub connectivity were investigated across multiple brain modules (the DMN, motor system, etcetera): (1) within-module connectivity (a measure of local importance that assesses a parcel's communication level within its own subnetwork) and (2) between-module connectivity (a measure that assesses connections across multiple modules). In TLE patients, there was lower overall functional integrity of the DMN as well as an increase in posterior hub connections with other modules. Anatomical between-module connectivity was globally decreased. Higher DMN disintegration (DD) coincided with higher anatomical between-module connectivity, whereas both were associated with increased seizure frequency. DD related to seizure frequency through mediating effects of anatomical connectivity, but seizure frequency also correlated with anatomical connectivity through DD, indicating a complex interaction between multimodal networks and symptoms. We provide evidence for dissociated anatomical and functional hub connectivity in TLE. Moreover, shifts in functional hub connections from within to outside the DMN, an overall loss of integrative anatomical communication, and the interaction between the two increase seizure frequency.

  9. Neurogenesis in the Hippocampus of Patients with Temporal Lobe Epilepsy.

    Science.gov (United States)

    Zhong, Qin; Ren, Bo-Xu; Tang, Feng-Ru

    2016-02-01

    The mobilization of endogenous neural stem cells in order to substitute lost neurons in the adult brain may reduce the negative effects of patients with chronic neurodegenerative diseases. However, abnormal neurogenesis may be harmful and could lead to the worsening of patients' symptoms. In the brains of patients and animal models with temporal lobe epilepsy (TLE), increased newly generated neurons in the subgranular zone (SGZ) at early stages after brain insults have been speculated to be involved in epileptogenesis. However, this argument is unsupported by evidence showing that (1) hippocampal neurogenesis is reduced at chronic stages of intractable TLE, (2) decreased neurogenesis is involved in epileptogenesis, and (3) spontaneous recurrent seizures occur before newly generated neurons are integrated into hippocampal neural pathways. Therefore, the hypothesis of increased neurogenesis in epileptogenesis may need to be re-evaluated. In this paper, we systemically reviewed brain neurogenesis and relevant molecules in the regulation of neurogenesis in SGZ. We aimed to update researchers and epileptologists on current progresses on pathophysiological changes of neurogenesis at different stages of TLE in patients and animal models of TLE. The interactions among neurogenesis, epileptogenesis and cognitive impairment, and molecules' mechanism involved in neurogenesis would also be discussed. Future research directions are proposed at the end of this paper.

  10. Seizure-Induced Oxidative Stress in Temporal Lobe Epilepsy

    Directory of Open Access Journals (Sweden)

    Sreekanth Puttachary

    2015-01-01

    Full Text Available An insult to the brain (such as the first seizure causes excitotoxicity, neuroinflammation, and production of reactive oxygen/nitrogen species (ROS/RNS. ROS and RNS produced during status epilepticus (SE overwhelm the mitochondrial natural antioxidant defense mechanism. This leads to mitochondrial dysfunction and damage to the mitochondrial DNA. This in turn affects synthesis of various enzyme complexes that are involved in electron transport chain. Resultant effects that occur during epileptogenesis include lipid peroxidation, reactive gliosis, hippocampal neurodegeneration, reorganization of neural networks, and hypersynchronicity. These factors predispose the brain to spontaneous recurrent seizures (SRS, which ultimately establish into temporal lobe epilepsy (TLE. This review discusses some of these issues. Though antiepileptic drugs (AEDs are beneficial to control/suppress seizures, their long term usage has been shown to increase ROS/RNS in animal models and human patients. In established TLE, ROS/RNS are shown to be harmful as they can increase the susceptibility to SRS. Further, in this paper, we review briefly the data from animal models and human TLE patients on the adverse effects of antiepileptic medications and the plausible ameliorating effects of antioxidants as an adjunct therapy.

  11. The selectivity and functional connectivity of the anterior temporal lobes.

    Science.gov (United States)

    Simmons, W Kyle; Reddish, Mark; Bellgowan, Patrick S F; Martin, Alex

    2010-04-01

    One influential account asserts that the anterior temporal lobe (ATL) is a domain-general hub for semantic memory. Other evidence indicates it is part of a domain-specific social cognition system. Arbitrating these accounts using functional magnetic resonance imaging has previously been difficult because of magnetic susceptibility artifacts in the region. The present study used parameters optimized for imaging the ATL, and had subjects encode facts about unfamiliar people, buildings, and hammers. Using both conjunction and region of interest analyses, person-selective responses were observed in both the left and right ATL. Neither building-selective, hammer-selective nor domain-general responses were observed in the ATLs, although they were observed in other brain regions. These findings were supported by "resting-state" functional connectivity analyses using independent datasets from the same subjects. Person-selective ATL clusters were functionally connected with the brain's wider social cognition network. Rather than serving as a domain-general semantic hub, the ATLs work in unison with the social cognition system to support learning facts about others.

  12. Temporal lobe dysfunction in childhood autism: a PET study

    International Nuclear Information System (INIS)

    Boddaert, N.; Poline, J.B.; Brunelle, F.; Zilbovicius, M.; Boddaert, N.; Brunelle, F.; Chabane, N.; Barthelemy, C.; Zilbovicius, M.; Bourgeois, M.; Samson, Y.

    2002-01-01

    Childhood autism is a severe developmental disorder that impairs the acquisition of some of the most important skills in human life. Progress in understanding the neural basis of childhood autism requires clear and reliable data indicating specific neuro-anatomical or neuro-physiological abnormalities. The purpose of the present study was to research localized brain dysfunction in autistic children using functional brain imaging. Regional cerebral blood flow (rCBF) was measured with positron emission tomography (PET) in 21 primary autistic children and 10 age-matched non autistic children. A statistical parametric analysis of rCBF images revealed significant bilateral temporal hypoperfusion in the associative auditory cortex (superior temporal gyrus) and in the multimodal cortex (superior temporal sulcus) in the autistic group (p<0.001). In addition, temporal hypoperfusion was detected individually in 77% of autistic children. These findings provide robust evidence of well localized functional abnormalities in autistic children located in the superior temporal lobe. Such localized abnormalities were not detected with the low resolution PET camera (14-22). This study suggests that high resolution PET camera combined with statistical parametric mapping is useful to understand developmental disorders. (authors)

  13. Autonoetic Consciousness in Autobiographical Memories after Medial Temporal Lobe Resection

    Directory of Open Access Journals (Sweden)

    M. Noulhiane

    2008-01-01

    Full Text Available This study aims to investigate autonoetic consciousness associated with episodic autobiographical memory in patients who had undergone unilateral medial temporal lobe resection for intractable epilepsy. Autonoetic consciousness, defined as the conscious feeling of mentally travelling back in time to relive a specific event, was assessed using the Remember/Know (R/K paradigm across different time periods as proposed in the autobiographical memory task developed by Piolino et al. (TEMPau task. Results revealed that the two patient groups (left and right temporal resection gave reduced sense of reliving (R responses and more familiarity (K responses than healthy controls. This poor autonoetic consciousness was highlighted when patients were asked to justify their Remember responses by recalling sensory-perceptive, affective or spatiotemporal specific details across all life periods. These results support the bilateral MTL contribution to episodic autobiographical memory covering the entire lifespan, which is consistent with the multiple trace theory of MTL function [7,9]. This study also demonstrates the bilateral involvement of MTL structures in recalling specific details of personal events characterized by autonoetic consciousness.

  14. Autonoetic Consciousness in Autobiographical Memories after Medial Temporal Lobe Resection

    Science.gov (United States)

    Noulhiane, M.; Piolino, P.; Hasboun, D.; Clemenceau, S.; Baulac, M.; Samson, S.

    2008-01-01

    This study aims to investigate autonoetic consciousness associated with episodic autobiographical memory in patients who had undergone unilateral medial temporal lobe resection for intractable epilepsy. Autonoetic consciousness, defined as the conscious feeling of mentally travelling back in time to relive a specific event, was assessed using the Remember/Know (R/K) paradigm across different time periods as proposed in the autobiographical memory task developed by Piolino et al. (TEMPau task). Results revealed that the two patient groups (left and right temporal resection) gave reduced sense of reliving (R) responses and more familiarity (K) responses than healthy controls. This poor autonoetic consciousness was highlighted when patients were asked to justify their Remember responses by recalling sensory-perceptive, affective or spatiotemporal specific details across all life periods. These results support the bilateral MTL contribution to episodic autobiographical memory covering the entire lifespan, which is consistent with the multiple trace theory of MTL function [7,9]. This study also demonstrates the bilateral involvement of MTL structures in recalling specific details of personal events characterized by autonoetic consciousness. PMID:18413911

  15. Medial temporal lobe roles in human path integration.

    Directory of Open Access Journals (Sweden)

    Naohide Yamamoto

    Full Text Available Path integration is a process in which observers derive their location by integrating self-motion signals along their locomotion trajectory. Although the medial temporal lobe (MTL is thought to take part in path integration, the scope of its role for path integration remains unclear. To address this issue, we administered a variety of tasks involving path integration and other related processes to a group of neurosurgical patients whose MTL was unilaterally resected as therapy for epilepsy. These patients were unimpaired relative to neurologically intact controls in many tasks that required integration of various kinds of sensory self-motion information. However, the same patients (especially those who had lesions in the right hemisphere walked farther than the controls when attempting to walk without vision to a previewed target. Importantly, this task was unique in our test battery in that it allowed participants to form a mental representation of the target location and anticipate their upcoming walking trajectory before they began moving. Thus, these results put forth a new idea that the role of MTL structures for human path integration may stem from their participation in predicting the consequences of one's locomotor actions. The strengths of this new theoretical viewpoint are discussed.

  16. Hemichorea and dystonia due to frontal lobe meningioma

    Directory of Open Access Journals (Sweden)

    Abdul Qayyum Rana

    2014-01-01

    Full Text Available Tumors originating from the meninges, also known as meningiomas, have rarely been known to cause parkinsonian symptoms and other movement disorders. Although some cases of AV malformations causing movement disorders have been described in the literature, not much has been reported about meningiomas in this regard. The aim of this case report is to further highlight the importance of brain imaging in patients with movement disorders for even a benign tumor; and also emphasize the need for a careful movement disorder examination because more than one phenomenology of movement disorders may result from the mechanical pressure caused by a tumor. We present a case report of a patient with a heavily calcified right frontal lobe meningioma. Our patient had irregular, involuntary, brief, fleeting and unpredictable movements of her left upper and lower extremities, consistent with chorea. The patient also had abnormal dystonic posturing of her left arm while walking. This case report highlights the importance of brain imaging as well as careful neurological examinations of patients with benign meningiomas. Moreover, it illustrates the remarkable specificity yet clinical diversity of meningiomas in presentation through movement disorders.

  17. Memory for emotional material in temporal lobe epilepsy.

    Science.gov (United States)

    Múnera, Claudia P; Lomlomdjian, Carolina; Terpiluk, Verónica; Medel, Nancy; Solís, Patricia; Kochen, Silvia

    2015-11-01

    Several studies suggest that highly emotional information could facilitate long-term memory encoding and consolidation processes via an amygdala-hippocampal network. Our aim was to assess emotional perception and episodic memory for emotionally arousing material in patients with temporal lobe epilepsy (TLE) who are candidates for surgical treatment. We did this by using an audiovisual paradigm. Forty-six patients with medically resistant TLE (26 with left TLE and 20 with right TLE) and 19 healthy controls were assessed with a standard narrative test of emotional memory. The experimental task consisted of sequential picture slides with an accompanying narrative depicting a story that has an emotional central section. Subjects were asked to rate their emotional arousal reaction to each stimulus after the story was shown, while emotional memory (EM) was assessed a week later with a multiple choice questionnaire and a visual recognition task. Our results showed that ratings for emotional stimuli for the patients with TLE were significantly higher than for neutral stimuli (p=0.000). It was also observed that patients with TLE recalled significantly less information from each slide compared with controls, with a trend to lower scores on the questionnaire task for the group with LTLE, as well as poorer performance on the visual recognition task for the group with RLTE. Emotional memory was preserved in patients with RTLE despite having generally poorer memory performance compared with controls, while it was found to be impaired in patients with LTLE. Copyright © 2015 Elsevier Inc. All rights reserved.

  18. Influence of anxiety on memory performance in temporal lobe epilepsy.

    Science.gov (United States)

    Brown, Franklin C; Westerveld, Michael; Langfitt, John T; Hamberger, Marla; Hamid, Hamada; Shinnar, Shlomo; Sperling, Michael R; Devinsky, Orrin; Barr, William; Tracy, Joseph; Masur, David; Bazil, Carl W; Spencer, Susan S

    2014-02-01

    This study examined the degree to which anxiety contributed to inconsistent material-specific memory difficulties among 243 patients with temporal lobe epilepsy from the Multisite Epilepsy Study. Visual memory performance on the Rey Complex Figure Test (RCFT) was poorer for those with high versus low levels of anxiety but was not found to be related to the TLE side. The verbal memory score on the California Verbal Learning Test (CVLT) was significantly lower for patients with left-sided TLE than for patients with right-sided TLE with low anxiety levels but equally impaired for those with high anxiety levels. These results suggest that we can place more confidence in the ability of verbal memory tests like the CVLT to lateralize to left-sided TLE for those with low anxiety levels, but that verbal memory will be less likely to produce lateralizing information for those with high anxiety levels. This suggests that more caution is needed when interpreting verbal memory tests for those with high anxiety levels. These results indicated that RCFT performance was significantly affected by anxiety and did not lateralize to either side, regardless of anxiety levels. This study adds to the existing literature which suggests that drawing-based visual memory tests do not lateralize among patients with TLE, regardless of anxiety levels. © 2013.

  19. Default network connectivity in medial temporal lobe amnesia.

    Science.gov (United States)

    Hayes, Scott M; Salat, David H; Verfaellie, Mieke

    2012-10-17

    There is substantial overlap between the brain regions supporting episodic memory and the default network. However, in humans, the impact of bilateral medial temporal lobe (MTL) damage on a large-scale neural network such as the default mode network is unknown. To examine this issue, resting fMRI was performed with amnesic patients and control participants. Seed-based functional connectivity analyses revealed robust default network connectivity in amnesia in cortical default network regions such as medial prefrontal cortex, posterior medial cortex, and lateral parietal cortex, as well as evidence of connectivity to residual MTL tissue. Relative to control participants, decreased posterior cingulate cortex connectivity to MTL and increased connectivity to cortical default network regions including lateral parietal and medial prefrontal cortex were observed in amnesic patients. In contrast, somatomotor network connectivity was intact in amnesic patients, indicating that bilateral MTL lesions may selectively impact the default network. Changes in default network connectivity in amnesia were largely restricted to the MTL subsystem, providing preliminary support from MTL amnesic patients that the default network can be fractionated into functionally and structurally distinct components. To our knowledge, this is the first examination of the default network in amnesia.

  20. Interictal psychosis following temporal lobe surgery: dentate gyrus pathology.

    Science.gov (United States)

    Thom, M; Kensche, M; Maynard, J; Liu, J; Reeves, C; Goc, J; Marsdon, D; Fluegel, D; Foong, J

    2014-10-01

    De novo interictal psychosis, albeit uncommon, can develop in patients following temporal lobe surgery for epilepsy. Pathological alterations of the dentate gyrus, including cytoarchitectural changes, immaturity and axonal reorganization that occur in epilepsy, may also underpin co-morbid psychiatric disorders. Our aim was to study candidate pathways that may be associated with the development of interictal psychosis post-operatively in patients with hippocampal sclerosis (HS). A total of 11 patients with HS who developed interictal psychosis (HS-P) post-operatively were compared with a matched surgical HS group without psychosis (HS-NP). Resected tissues were investigated for the extent of granule cell dispersion, mossy fibre sprouting and calbindin expression in the granule cells. We quantified doublecortin, mini-chromosome maintenance protein 2 (MCM2) and reelin-expressing neuronal populations in the dentate gyrus as well as the distribution of cannabinoid type 1 receptor (CBR1). The patterns of neuronal loss and gliosis were similar in both groups. HS-P patients demonstrated less mossy fibre sprouting and granule cell dispersion (p gyrus pathology found in HS-P patients could indicate underlying differences in the cellular response to seizures. These mechanisms may predispose to the development of psychosis in epilepsy and warrant further investigation.

  1. Hsp60 response in experimental and human temporal lobe epilepsy

    Science.gov (United States)

    Gammazza, Antonella Marino; Colangeli, Roberto; Orban, Gergely; Pierucci, Massimo; Di Gennaro, Giancarlo; Bello, Margherita Lo; D'Aniello, Alfredo; Bucchieri, Fabio; Pomara, Cristoforo; Valentino, Mario; Muscat, Richard; Benigno, Arcangelo; Zummo, Giovanni; de Macario, Everly Conway; Cappello, Francesco; Di Giovanni, Giuseppe; Macario, Alberto J. L.

    2015-01-01

    The mitochondrial chaperonin Hsp60 is a ubiquitous molecule with multiple roles, constitutively expressed and inducible by oxidative stress. In the brain, Hsp60 is widely distributed and has been implicated in neurological disorders, including epilepsy. A role for mitochondria and oxidative stress has been proposed in epileptogenesis of temporal lobe epilepsy (TLE). Here, we investigated the involvement of Hsp60 in TLE using animal and human samples. Hsp60 immunoreactivity in the hippocampus, measured by Western blotting and immunohistochemistry, was increased in a rat model of TLE. Hsp60 was also increased in the hippocampal dentate gyrus neurons somata and neuropil and hippocampus proper (CA3, CA1) of the epileptic rats. We also determined the circulating levels of Hsp60 in epileptic animals and TLE patients using ELISA. The epileptic rats showed circulating levels of Hsp60 higher than controls. Likewise, plasma post-seizure Hsp60 levels in patients were higher than before the seizure and those of controls. These results demonstrate that Hsp60 is increased in both animals and patients with TLE in affected tissues, and in plasma in response to epileptic seizures, and point to it as biomarker of hippocampal stress potentially useful for diagnosis and patient management. PMID:25801186

  2. Seizure semiology of lesional frontal lobe epilepsies in children.

    Science.gov (United States)

    Battaglia, D; Lettori, D; Contaldo, I; Veredice, C; Sacco, A; Vasco, J; Martinelli, D; Chieffo, D; Tartaglione, T; Colosimo, C; Di Rocco, C; Guzzetta, F

    2007-12-01

    The aim of the study was to analyse the semiology of seizures in children with frontal lobe epilepsy (FLE) and to compare them with other paediatric cohorts described in the literature as well as with adult counterparts. We analysed 174 registered seizures of 18 cases under 12 years with lesional epilepsy whose frontal origin was defined by the concordance of neuroimaging and ictal electrographic findings, and confirmed by surgery in the six cases operated on. Seizures were generally short, with a high daily frequency and usually related to sleep. The most characteristic semiological pattern consisted of complex motor seizures, particularly hypermotor. Often seizures corresponded to a mixture of different semiological patterns (tonic, gelastic, automotor, hypermotor, versive) presenting in the same seizure, often as a unique type in the same patient. With regard to several aspects the semiology of FLE in our cohort looks like that reported in adult series, in particular as to the frequency of complex motor seizures. However, our cohort was also characterised by a more protean array of seizure semiology, stressing the occurrence of seizures typically present in adults (versive and complex motor) and of some seizure patterns more characteristic in children such as epileptic spasms; moreover, the rare occurrence of secondarily generalised tonic clonic seizures (SGTCS) was confirmed.

  3. Age-dependent seizure semiology in temporal lobe epilepsy.

    Science.gov (United States)

    Fogarasi, András; Tuxhorn, Ingrid; Janszky, József; Janszky, Imre; Rásonyi, György; Kelemen, Anna; Halász, Péter

    2007-09-01

    To examine the effects of age on different aspects of temporal lobe seizure semiology. We performed a video analysis of 605 archived seizures from 155 consecutive patients (age 10 months to 49 years) selected by seizure freedom after temporal lobectomy. Eighty patients had hippocampal sclerosis (HS). Beside semiological seizure classification, we assessed age dependency of several axes of seizure semiology: (1) aura, (2) number of different lateralizing signs, occurrence of ictal (3) emotional signs, (4) autonomic symptoms, (5) automatisms, and (6) secondary generalization as well as (7) the ratio of motor seizure components. From the 155 patients, 117 reported aura, 39 had ictal emotional signs, 51 had autonomic symptoms, 130 presented automatisms, while 18 patients showed secondary generalization at least once during their seizures. Altogether 369 (median: 2/patient) different lateralizing signs were recorded. Frequency of HS (p semiology. Conversely, other aspects (aura, emotional, and autonomic signs) are independent of the maturation process. This is the first report investigating age dependency of epileptic seizure semiology comparing all age groups.

  4. Rat intermediate lobe in culture: a histological and biochemical characterization.

    Science.gov (United States)

    Chronwall, B M; Bishop, J F; Gehlert, D R

    1988-01-01

    The histology, immunohistochemistry, peptide synthesis and secretion as well as proliferation rate of rat intermediate lobe (IL) were studied in primary cultures. The cultures contained two populations of cells: melanotrophs either organized in free floating lobules or in lobules which attached to the dishes and formed a monolayer. Both populations retained their in vivo morphology: polyhedral cells with smooth, ovoid nuclei and a large number of cytoplasmic secretory coated vesicles, a well developed Golgi apparatus, abundant mitochondria and extensive areas of rough endoplasmic reticulum. The melanotrophs stained with varying intensity for alpha-MSH and in situ hybridization showed the presence of pro-opiomelanocortin (POMC) mRNA. 35S-methionine incorporation combined with 2-D gel electrophoresis demonstrated POMC peptide synthesis and radioimmunoassay confirmed its secretion into the medium. 3H-thymidine uptake in the attached melanotrophs was considerably higher than that in the free-floating melanotrophs, demonstrating the dependency of proliferation rate on the cytoarchitecture of the explant. The retention of melanotroph morphology, biosynthetic and proliferative capacity in vitro affords a valid model system for studying POMC gene expression.

  5. Anterior Temporal Lobe Tracks the Formation of Prejudice.

    Science.gov (United States)

    Spiers, Hugo J; Love, Bradley C; Le Pelley, Mike E; Gibb, Charlotte E; Murphy, Robin A

    2017-03-01

    Despite advances in understanding the brain structures involved in the expression of stereotypes and prejudice, little is known about the brain structures involved in their acquisition. Here, we combined fMRI, a task involving learning the valence of different social groups, and modeling of the learning process involved in the development of biases in thinking about social groups that support prejudice. Participants read descriptions of valenced behaviors performed by members of novel social groups, with majority groups being more frequently encountered during learning than minority groups. A model-based fMRI analysis revealed that the anterior temporal lobe tracked the trial-by-trial changes in the valence associated with each group encountered in the task. Descriptions of behavior by group members that deviated from the group average (i.e., prediction errors) were associated with activity in the left lateral PFC, dorsomedial PFC, and lateral anterior temporal cortex. Minority social groups were associated with slower acquisition rates and more activity in the ventral striatum and ACC/dorsomedial PFC compared with majority groups. These findings provide new insights into the brain regions that (a) support the acquisition of prejudice and (b) detect situations in which an individual's behavior deviates from the prejudicial attitude held toward their group.

  6. Corpora amylacea in temporal lobe epilepsy associated with hippocampal sclerosis

    Directory of Open Access Journals (Sweden)

    Ribeiro Marlise de Castro

    2003-01-01

    Full Text Available Hippocampal sclerosis (HS is the commonest pathology in epileptic patients undergoing temporal lobe epilepsy surgery. Beside, there are an increased density of corpora amylacea (CA founded in 6 to 63% of those cases. OBJECTIVE: verify the presence of CA and the clinical correlates of their occurrence in a consective series of patients undergoing temporal surgery with diagnosis of HS. METHOD: We reviewed 72 hippocampus specimens from January 1997 to July 2000. Student's t test for independent, samples, ANOVA and Tukey test were performed for statistical analysis. RESULTS: CA were found in 35 patients (49%, whose mean epilepsy duration (28.7 years was significantly longer than that group of patients without CA (19.5 years, p= 0.001. Besides, when CA were found, duration was also significantly correlated with distribution within hippocampus: 28.7 years with diffuse distribution of CA, 15.4 with exclusively subpial and 17.4 years with distribution subpial plus perivascular (p= 0.001. CONCLUSION: Our findings corroborate the presence of CA in patients with HS and suggest that a longer duration of epilepsy correlate with a more distribution of CA in hippocampus.

  7. Variations on a Theme: Antennal Lobe Architecture across Coleoptera.

    Science.gov (United States)

    Kollmann, Martin; Schmidt, Rovenna; Heuer, Carsten M; Schachtner, Joachim

    2016-01-01

    Beetles comprise about 400,000 described species, nearly one third of all known animal species. The enormous success of the order Coleoptera is reflected by a rich diversity of lifestyles, behaviors, morphological, and physiological adaptions. All these evolutionary adaptions that have been driven by a variety of parameters over the last about 300 million years, make the Coleoptera an ideal field to study the evolution of the brain on the interface between the basic bauplan of the insect brain and the adaptions that occurred. In the current study we concentrated on the paired antennal lobes (AL), the part of the brain that is typically responsible for the first processing of olfactory information collected from olfactory sensilla on antenna and mouthparts. We analyzed 63 beetle species from 22 different families and thus provide an extensive comparison of principal neuroarchitecture of the AL. On the examined anatomical level, we found a broad diversity including AL containing a wide range of glomeruli numbers reaching from 50 to 150 glomeruli and several species with numerous small glomeruli, resembling the microglomerular design described in acridid grasshoppers and diving beetles, and substructures within the glomeruli that have to date only been described for the small hive beetle, Aethina tumida. A first comparison of the various anatomical features of the AL with available descriptions of lifestyle and behaviors did so far not reveal useful correlations. In summary, the current study provides a solid basis for further studies to unravel mechanisms that are basic to evolutionary adaptions of the insect olfactory system.

  8. Continuous Intraoperative Monitoring of Temporal Lobe Epilepsy Surgery.

    Science.gov (United States)

    Tyrand, Rémi; Momjian, Shahan; Pollo, Claudio; Lysakowski, Christopher; Lascano, Agustina M; Vulliémoz, Serge; Schaller, Karl; Boëx, Colette

    2016-01-01

    The monitoring of interictal epileptiform discharge rates (IEDRs) all along anterior temporal lobe resections (ATLRs) has never been reported. Here the effect of ATLR on continuous IEDR monitoring is described. IEDRs computed automatically during entire interventions were recorded in 34 patients (38.2%, 13/34 depth; 61.8%, 21/34 scalp electrodes only). Monitorings were invalidated when burst suppression occurred or if initial IEDRs were <5. Monitoring was successful for 69.2% (9/13) of the patients with depth recordings and for 4.8% (1/21) of the patients with scalp recordings. Burst suppressions precluded it in 30.8% (4/13) of the depth and in 57.1% (12/21) of the scalp recordings. Initial IEDRs were <5 for 38.1% (8/21) of the scalp recordings. Significant IEDR decreases were observed in 8/10 patients with successful monitoring. These decreases started with resection of the superior temporal gyrus. IEDRs decreased further with amygdalohippocampectomy in 3/5 patients. At the 12-month follow-up, all patients with IEDR decreases remained seizure free; both patients without did not. IEDR monitoring was possible with depth, but not with scalp electrodes. IEDR decreases started with resection of the superior temporal gyrus. A larger patient cohort is necessary to confirm the high predictive values of IEDR monitoring that could become a tool for surgery customization. © 2016 S. Karger AG, Basel.

  9. A Novel Approach to Prenatal Measurement of the Fetal Frontal Lobe Using Three-Dimensional Sonography.

    Science.gov (United States)

    Brown, Steffen A; Hall, Rebecca; Hund, Lauren; Gutierrez, Hilda L; Hurley, Timothy; Holbrook, Bradley D; Bakhireva, Ludmila N

    2017-01-01

    While prenatal 3D ultrasonography results in improved diagnostic accuracy, no data are available on biometric assessment of the fetal frontal lobe. This study was designed to assess feasibility of a standardized approach to biometric measurement of the fetal frontal lobe and to construct frontal lobe growth trajectories throughout gestation. A sonographic 3D volume set was obtained and measured in 101 patients between 16.1 and 33.7 gestational weeks. Measurements were obtained by two independent raters. To model the relationship between gestational age and each frontal lobe measurement, flexible linear regression models were fit using penalized regression splines. The sample contained an ethnically diverse population (7.9% Native Americans, 45.5% Hispanic/Latina). There was high inter-rater reliability (correlation coefficients: 0.95, 1.0, and 0.87 for frontal lobe length, width, and height; p-values frontal lobe growth were 0.096 cm/week, 0.247 cm/week, and 0.111 cm/week for length, width, and height. To our knowledge, this is the first study to examine fetal frontal lobe growth trajectories through 3D prenatal ultrasound examination. Such normative data will allow for future prenatal evaluation of a particular disease state by 3D ultrasound imaging.

  10. [Hepatocellular carcinoma originated in the caudate lobe. Surgical strategy for resection. A propos of a case].

    Science.gov (United States)

    Martínez-Mier, Gustavo; Esquivel-Torres, Sergio; Calzada-Grijalva, José Francisco; Grube-Pagola, Peter

    2015-01-01

    Hepatocellular carcinoma originating from the caudate lobe has a worse prognosis than other hepatocellular carcinoma in another segment of the liver. An isolated caudate lobe resection of the liver represents a significant technical challenge. Caudate lobe resection can be performed along with a lobectomy or as an isolated liver resection. There are very few reports about isolated caudate lobe liver resection. We report a case of successful isolated resection of hepatocellular carcinoma in the caudate lobe with excellent long-term survival. A 74 years old female with 8cm mass lesion in the caudate lobe without clinical or biochemical evidence of liver cirrhosis, serum alpha-fetoprotein 3.7 U/l, and negative hepatitis serology was evaluated for surgery. Complete resection of the lesion in 270minutes with Pringle maneuver for 13minutes was satisfactorily performed. Patient was discharged ten days after surgery without complications. Patient is currently asymptomatic, without deterioration of liver function and 48 month tumor free survival after the procedure. Isolated caudate lobe resection is an uncommon but technically possible procedure. In order to achieve a successful resection, one must have a detailed knowledge of complete liver anatomy. Tumor free margins must be obtained to provide long survival for these patients who have a malignancy in this anatomic location. Copyright © 2015. Published by Masson Doyma México S.A.

  11. ON THE ORIGIN OF FANAROFF-RILEY CLASSIFICATION OF RADIO GALAXIES: DECELERATION OF SUPERSONIC RADIO LOBES

    International Nuclear Information System (INIS)

    Kawakatu, Nozomu; Kino, Motoki; Nagai, Hiroshi

    2009-01-01

    We argue that the origin of 'FRI/FRII dichotomy' - the division between Fanaroff-Riley class I (FRI) with subsonic lobes and class II (FRII) radio sources with supersonic lobes is sharp in the radio-optical luminosity plane (Owen-White diagram) - can be explained by the deceleration of advancing radio lobes. The deceleration is caused by the growth of the effective cross-sectional area of radio lobes. We derive the condition in which an initially supersonic lobe turns into a subsonic lobe, combining the ram pressure equilibrium between the hot spots and the ambient medium with the relation between 'the hot spot radius' and 'the linear size of radio sources' obtained from the radio observations. We find that the dividing line between the supersonic lobes and subsonic ones is determined by the ratio of the jet power L j to the number density of the ambient matter at the core radius of the host galaxy n-bar a . It is also found that the maximal ratio of (L j ,n-bar a ) exists and its value resides in (L j ,n-bar a ) max ∼10 44-47 er s -1 cm 3 , taking into account considerable uncertainties. This suggests that the maximal value (L j ,n-bar a ) max separates between FRIs and FRIIs.

  12. Middle lobe syndrome: a review of clinicopathological features, diagnosis and treatment.

    Science.gov (United States)

    Gudbjartsson, Tomas; Gudmundsson, Gunnar

    2012-01-01

    Middle lobe syndrome (MLS) is a rare but important clinical entity that has been poorly defined in the literature. It is characterized by recurrent or chronic collapse of the middle lobe of the right lung but can also involve the lingula of the left lung. Pathophysiologically, there are two forms of MLS, namely obstructive and nonobstructive. Obstructive MLS is usually caused by endobronchial lesions or extrinsic compression of the middle lobe bronchus such as from hilar lymphadenopathy or tumors of neoplastic origin, resulting in postobstructive atelectasis and pneumonitis. In the nonobstructive type, no obstruction of the middle lobe bronchus is evident during bronchoscopy or with computerized tomography of the chest. The etiology of the nonobstructive form is not completely understood. Inefficient collateral ventilation, infection and inflammation in the middle lobe or lingula are thought to play a role, and bronchiectasis is the most common histological finding. Patients with proven endobronchial lesions or malignancy are usually offered surgical resection directly. This contrasts with nonobstructive MLS, where most patients respond to medical treatment consisting of bronchodilators, mucolytics and broad-spectrum antibiotics. However, some patients do not respond to conservative treatment and may suffer irreversible damage of the middle lobe or lingula, in addition to having recurrent symptoms of infection or inflammation. These selected patients can be offered surgical resection of the middle lobe or lingula, which is associated with a low mortality rate and favorable outcome. Copyright © 2012 S. Karger AG, Basel.

  13. Activation on occipital lobe in children with abacus mental calculation training: an fMRI study

    International Nuclear Information System (INIS)

    Shen Xiaojun; Long Jinfeng; Zhao Kunyuan; Li Lixin; Sun Jining; Wang Bin

    2011-01-01

    Objective: By exploring the activation on occipital lobe in children with and without abacus mental calculation training when they engaged in different calculation tasks with functional magnetic resonance imaging (fMRI), to identify the possible mechanism of occipital lobe in abacus mental calculation. Methods: fMRI was performed in children trained with and without (sixteen in each group) abacus mental calculation when they engaged in addition, subtraction. multiplication, division, and number-object control judging tasks. The data processing and statistical analysis were performed on SPM 2.0 (statistical parametric mapping 2.0) and the related-brain functional areas were identified. The activation on occipital lobe was observed carefully. The difference in activated areas of occipital lobe was statistically significant between two groups engaged in different tasks of calculations (P<0.01). Result: Bilateral occipital lobe, especially in the cuneus and lingual gyrus, were activated in children trained with abacus mental calculation. The main activated area was lingual gyrus in children without abacus mental calculation. Conclusion: The occipital lobe participates visuospatial processing in the abacus mental calculations. The neuromechanism maybe account for the specific activation in occipital lobe. (authors)

  14. Pulmonary lobe separation in expiration chest CT scans based on subject-specific priors derived from inspiration scans.

    Science.gov (United States)

    Bauer, Christian; Eberlein, Michael; Beichel, Reinhard R

    2018-01-01

    Segmentation of pulmonary lobes in inspiration and expiration chest CT scan pairs is an important prerequisite for lobe-based quantitative disease assessment. Conventional methods process each CT scan independently, resulting typically in lower segmentation performance at expiration compared to inspiration. To address this issue, we present an approach, which utilizes CT scans at both respiratory states. It consists of two main parts: a base method that processes a single CT scan and an extended method that utilizes the segmentation result obtained on the inspiration scan as a subject-specific prior for segmentation of the expiration scan. We evaluated the methods on a diverse set of 40 CT scan pairs. In addition, we compare the performance of our method to a registration-based approach. On inspiration scans, the base method achieved an average distance error of 0.59, 0.64, and 0.91 mm for the left oblique, right oblique, and right horizontal fissures, respectively, when compared with expert-based reference tracings. On expiration scans, the base method's errors were 1.54, 3.24, and 3.34 mm, respectively. In comparison, utilizing proposed subject-specific priors for segmentation of expiration scans allowed decreasing average distance errors to 0.82, 0.79, and 1.04 mm, which represents a significant improvement ([Formula: see text]) compared with all other methods investigated.

  15. Atlasing the frontal lobe connections and their variability due to age and education: a spherical deconvolution tractography study.

    Science.gov (United States)

    Rojkova, K; Volle, E; Urbanski, M; Humbert, F; Dell'Acqua, F; Thiebaut de Schotten, M

    2016-04-01

    In neuroscience, there is a growing consensus that higher cognitive functions may be supported by distributed networks involving different cerebral regions, rather than by single brain areas. Communication within these networks is mediated by white matter tracts and is particularly prominent in the frontal lobes for the control and integration of information. However, the detailed mapping of frontal connections remains incomplete, albeit crucial to an increased understanding of these cognitive functions. Based on 47 high-resolution diffusion-weighted imaging datasets (age range 22-71 years), we built a statistical normative atlas of the frontal lobe connections in stereotaxic space, using state-of-the-art spherical deconvolution tractography. We dissected 55 tracts including U-shaped fibers. We further characterized these tracts by measuring their correlation with age and education level. We reported age-related differences in the microstructural organization of several, specific frontal fiber tracts, but found no correlation with education level. Future voxel-based analyses, such as voxel-based morphometry or tract-based spatial statistics studies, may benefit from our atlas by identifying the tracts and networks involved in frontal functions. Our atlas will also build the capacity of clinicians to further understand the mechanisms involved in brain recovery and plasticity, as well as assist clinicians in the diagnosis of disconnection or abnormality within specific tracts of individual patients with various brain diseases.

  16. The effect of delayed auditory feedback on activity in the temporal lobe while speaking: a positron emission tomography study.

    Science.gov (United States)

    Takaso, Hideki; Eisner, Frank; Wise, Richard Js; Scott, Sophie K

    2010-04-01

    Delayed auditory feedback is a technique that can improve fluency in stutterers, while disrupting fluency in many nonstuttering individuals. The aim of this study was to determine the neural basis for the detection of and compensation for such a delay, and the effects of increases in the delay duration. Positron emission tomography was used to image regional cerebral blood flow changes, an index of neural activity, and to assess the influence of increasing amounts of delay. Delayed auditory feedback led to increased activation in the bilateral superior temporal lobes, extending into posterior-medial auditory areas. Similar peaks in the temporal lobe were sensitive to increases in the amount of delay. A single peak in the temporal parietal junction responded to the amount of delay but not to the presence of a delay (relative to no delay). This study permitted distinctions to be made between the neural response to hearing one's voice at a delay and the neural activity that correlates with this delay. Notably, all the peaks showed some influence of the amount of delay. This result confirms a role for the posterior, sensorimotor "how" system in the production of speech under conditions of delayed auditory feedback.

  17. Domain-specific impairment of source memory following a right posterior medial temporal lobe lesion.

    Science.gov (United States)

    Peters, Jan; Koch, Benno; Schwarz, Michael; Daum, Irene

    2007-01-01

    This single case analysis of memory performance in a patient with an ischemic lesion affecting posterior but not anterior right medial temporal lobe (MTL) indicates that source memory can be disrupted in a domain-specific manner. The patient showed normal recognition memory for gray-scale photos of objects (visual condition) and spoken words (auditory condition). While memory for visual source (texture/color of the background against which pictures appeared) was within the normal range, auditory source memory (male/female speaker voice) was at chance level, a performance pattern significantly different from the control group. This dissociation is consistent with recent fMRI evidence of anterior/posterior MTL dissociations depending upon the nature of source information (visual texture/color vs. auditory speaker voice). The findings are in good agreement with the view of dissociable memory processing by the perirhinal cortex (anterior MTL) and parahippocampal cortex (posterior MTL), depending upon the neocortical input that these regions receive. (c) 2007 Wiley-Liss, Inc.

  18. CT detection of thyroid pyramidal lobe in preoperative patients with thyroid tumors

    International Nuclear Information System (INIS)

    Shin, Gi Won; Kim, Dong Won

    2013-01-01

    Thyroid pyramidal lobe (TPL) is a normal variant of the thyroid gland, but few imaging studies of TPL have been published. The purpose of this study is to investigate the frequency, location, size (length, maximal AP diameter, maximal transverse diameter), and upper end level of TPL with its separation from the main thyroid gland on preoperative neck CT and to compare them with operative findings in order to assess the diagnostic accuracy of neck CT for detection TPL. 46 patients, who underwent preoperative neck CT before thyroidectomy, were included in the study. The frequency, location, size, and upper end level of TPL with its separation from the main thyroid gland on the neck CT was analyzed by a single radiologist. The sensitivity, specificity, positive predictive value, negative predictive value and accuracy of neck CT for detecting TPL was 77.8%, 89.5%, 91.3%, 73.9% and 82.6%. There was a significant difference in maximal AP diameter, location, upper end level, and its separation from main thyroid gland between CT and operative findings (p 0.05). Diagnostic accuracy of neck CT for detecting TPL was high, and the neck CT may be useful for evaluating TPL in the suprahyoid neck.

  19. Element shape design of 2-D CMUT arrays for reducing grating lobes.

    Science.gov (United States)

    Bavaro, Vito; Caliano, Giosuè; Pappalardo, Massimo

    2008-02-01

    Fully populated two-dimensional (2-D) arrays are needed to produce high quality ultrasonic volumetric images for real-time applications, but they present many challenges for their physical realization because of the large number of elements. In fact, lambda/2 and lambda minimum spacing between elements is required, respectively, for pyramidal and rectilinear scanning in order to avoid unwanted grating lobes (GLs). However, in past years, capacitive micromachined ultrasonic transducer (CMUT) technology has made possible the production of arrays with large flexibility in element shape and size. In this paper, this property is analyzed, and a new element shape, based on the concept of spatial interpenetration of adjacent elements, is proposed in order to design fully populated 2-D CMUT arrays with a low number of elements, whose beam characteristics are valid for volumetric imaging. Through the use of simulations, it is demonstrated that arrays with pitch larger than lambda (up to 3lambda) used for rectilinear scanning, have notably lower GLs than the equivalent standard arrays designed according to the classical squared element shape. As consequence, the proposed geometry has the advantage of reducing the number of elements (up to a factor of 9) and of enlarging the element size, implying an increase of the SNR relative to the single element. When beam steering is required, arrays can be designed with pitch equal to lambda, reducing the number of elements by a factor of 4 if the maximum steering angle is limited to +/-15 degrees .

  20. Clinical-physiologic correlates of Alzheimer's disease and frontal lobe dementia

    International Nuclear Information System (INIS)

    Jagust, W.J.; Reed, B.R.; Seab, J.P.; Kramer, J.H.; Budinger, T.F.

    1989-01-01

    Thirty patients with degenerative dementia underwent clinical evaluation, neuropsychological testing, and single photon emission computed tomography (SPECT) with the blood flow tracer [ 123 I]-N-isopropyl-p-iodoamphetamine. Five of these patients were clinically and psychologically different from the others, demonstrating predominant behavioral disturbances with relative preservation of memory function. These five patients, who were felt to have a frontal lobe dementia (FLD), showed SPECT perfusion patterns which differed from the remaining 25 patients, who were diagnosed as having Alzheimer's disease (AD), and from 16 healthy control subjects. The FLD patients showed diminished perfusion in orbitofrontal, dorsolateral frontal, and temporal cortex relative to controls, while the AD patients showed lower perfusion in temporal and parietal cortex than controls. The FLD patients also showed hypoperfusion in both frontal cortical regions relative to AD patients. The pattern of performance on neuropsychological testing paralleled these differences in regional perfusion. These results suggest that clinical evaluation and physiological imaging may enable the differentiation of groups of degenerative dementia patients during life

  1. Clinical and pathological study on 10 cases of cerebral lobe hemorrhage related with cerebral amyloid angiopathy

    Directory of Open Access Journals (Sweden)

    Xiao-qi LI

    2015-07-01

    Full Text Available Objective To summarize the clinical data and pathological features of 10 cases of cerebral lobar hemorrhage related with cerebral amyloid angiopathy (CAA diagnosed pathologically, thereby to improve the knowledge and diagnosis of the disease. Methods The clinical data of 10 cases of cerebral lobar hemorrhage related with CAA, collected in the General Hospital of Shenyang Command from 1983 up to now, were retrospectively analyzed, and the clinical and neuropathological features of these cases were summarized. Results Of the 10 patients, 2 suffered from single lobar hemorrhage and 8 multiple lobar hemorrhage, all of them were confirmed pathologically to have ruptured into the subarachnoid space. Pathological examination revealed microaneurysm in 2 cases, "double barrel" change in 4 cases, multiple arteriolar clusters in 5 cases, obliterative onion-liked intima change in 4 cases, and fibrinoid necrosis of vessel wall in 7 cases. In addition, neurofibrillary tangles were found in 8 cases, and senile plaque was observed in 5 cases. Conclusions Cerebral lobar hemorrhage related with CAA is mainly located in the parietal, temporal and occipital lobes, readily breaking into the subarachnoid space, and it is often multiple and recurrent. The CAA associated microvasculopathy was found frequently in the autopsy sample of CAA related cerebral lobar hemorrhage, and it may contribute to the pathogenesis of cerebral hemorrhage. DOI: 10.11855/j.issn.0577-7402.2015.07.04

  2. Functional neuroimaging studies of episodic memory. Functional dissociation in the medial temporal lobe structures

    International Nuclear Information System (INIS)

    Tsukiura, Takashi

    2008-01-01

    Previous functional neuroimaging studies have demonstrated the critical role of the medial temporal lobe (MTL) regions in the encoding and retrieval of episodic memory. It has also been shown that an emotional factor in human memory enhances episodic encoding and retrieval. However, there is little evidence regarding the specific contribution of each MTL region to the relational, contextual, and emotional processes of episodic memory. The goal of this review article is to identify differential activation patterns of the processes between MTL regions. Results from functional neuroimaging studies of episodic memory show that the hippocampus is involved in encoding the relation between memory items, whereas the entorhinal and perirhinal cortices (anterior parahippocampal gyrus) contribute to the encoding of a single item. Additionally, the parahippocampal cortex (posterior parahippocampal gyrus) is selectively activated during the processing of contextual information of episodic memory. A similar pattern of functional dissociation is found in episodic memory retrieval. Functional neuroimaging has also shown that emotional information of episodic memory enhances amygdala-MTL correlations and that this enhancement is observed during both the encoding and retrieval of emotional memories. These findings from pervious neuroimaging studies suggest that different MTL regions could organize memory for personally experienced episodes via the 'relation' and 'context' factors of episodic memory, and that the emotional factor of episodes could modulate the functional organization in the MTL regions. (author)

  3. Persistent impairment of liver function caused by a pendulated accessory liver lobe

    International Nuclear Information System (INIS)

    Fogh, J.; Tromholt, N.; Joergensen, F.

    1989-01-01

    A large pendulated accessory liver lobe and complete absence of the left lobe were discovered by liver scintigraphy and ultrasound scanning in a patient suspected of having an ovarian tumor. The patient had a history of fluctuating impaired liver function tests for many years, probably caused by intermittent torsion of the peduncle. Pedunculated accessory liver lobes are extremely rare and seldom diagnosed in vivo. Our patient seems to be the 11th published case, and the only one in which longstanding fluctuating impaired liver function tests have been observed. (orig.)

  4. Theoretical and Experimental Demonstration on Grating Lobes of Liquid Crystal Optical Phased Array

    Directory of Open Access Journals (Sweden)

    Xiangru Wang

    2016-01-01

    Full Text Available High deflection efficiency is one of the urgent requirements for practical liquid crystal optical phased array (LC-OPA. In this paper, we demonstrate that high order grating lobes induced from fringe effect are the most important issue to reduce occupation of main lobe. A novel theoretical model is developed to analyze the feature of grating lobes when the device of LC-OPA is working on the scheme of variable period grating (VPG or variable blazing grating (VBG. Subsequently, our experiments present the relevant results showing a good agreement with the theoretical analysis.

  5. Unstable Roche-Lobe Overflow of Gaseous Planets

    Science.gov (United States)

    Jackson, Brian

    The discoveries of more than 100 roughly Earth-sized bodies with orbital periods less than 1 day, ultra-short-period planets or candidates (USPs), have challenged planet formation theories, and evidence suggests USPs may be the remnants of gaseous planets that shed their atmospheres. Indeed, many hot Jupiters are near Roche-Lobe overflow (RLO), and tidal decay can push them the rest of the way in. Recent work has shown stable RLO (atmospheres lost via a steady outflow and thin accretion disk) probably cannot produce USPs on its own but suggested unstable RLO (atmospheres quickly shed on dynamical timescales) may. In fact, stable RLO may drive overflowing hot Jupiters into unstable RLO, and by analogy with the common-envelope binaries, the core that remains can drive off the gaseous envelope at the cost of its orbital energy. Wellestablished mass-radius relations for gaseous planets, coupled to simple energy and angular momentum considerations, provide a connection between the observed masses and periods for USPs and their putative progenitor gaseous planets, with few free parameters. We propose to investigate the hypothesis that USPs originate through tidal decay and a combination of stable and unstable Roche-lobe overflow of short-period gaseous planets through the following studies: -We will explore the planetary masses, orbital periods, etc. that produce unstable RLO using the Modules for Experiments in Stellar Astrophysics (MESA) suite. -We will relate the observed periods and masses of USPs to their putative progenitor masses and periods to see whether they are consistent with the unstable RLO hypothesis. This proposal is directly relevant to the Exoplanets Research Program since it seeks to "understand the ... physical processes of exoplanets" and "improve understanding of [their] origins" through "theoretical studies ... and modeling'". We also expect that it will have broad impacts on a variety of astrophysical topics: -Ultra-short period planets could

  6. Mechanisms of maximum information preservation in the Drosophila antennal lobe.

    Science.gov (United States)

    Satoh, Ryota; Oizumi, Masafumi; Kazama, Hokto; Okada, Masato

    2010-05-21

    We examined the presence of maximum information preservation, which may be a fundamental principle of information transmission in all sensory modalities, in the Drosophila antennal lobe using an experimentally grounded network model and physiological data. Recent studies have shown a nonlinear firing rate transformation between olfactory receptor neurons (ORNs) and second-order projection neurons (PNs). As a result, PNs can use their dynamic range more uniformly than ORNs in response to a diverse set of odors. Although this firing rate transformation is thought to assist the decoder in discriminating between odors, there are no comprehensive, quantitatively supported studies examining this notion. Therefore, we quantitatively investigated the efficiency of this firing rate transformation from the viewpoint of information preservation by computing the mutual information between odor stimuli and PN responses in our network model. In the Drosophila olfactory system, all ORNs and PNs are divided into unique functional processing units called glomeruli. The nonlinear transformation between ORNs and PNs is formed by intraglomerular transformation and interglomerular interaction through local neurons (LNs). By exploring possible nonlinear transformations produced by these two factors in our network model, we found that mutual information is maximized when a weak ORN input is preferentially amplified within a glomerulus and the net LN input to each glomerulus is inhibitory. It is noteworthy that this is the very combination observed experimentally. Furthermore, the shape of the resultant nonlinear transformation is similar to that observed experimentally. These results imply that information related to odor stimuli is almost maximally preserved in the Drosophila olfactory circuit. We also discuss how intraglomerular transformation and interglomerular inhibition combine to maximize mutual information.

  7. Temporal anteroinferior encephalocele: An underrecognized etiology of temporal lobe epilepsy?

    Science.gov (United States)

    Saavalainen, Taavi; Jutila, Leena; Mervaala, Esa; Kälviäinen, Reetta; Vanninen, Ritva; Immonen, Arto

    2015-10-27

    To report the increasing frequency with which temporal anteroinferior encephalocele is a cause of adult temporal lobe epilepsy, to illustrate the clinical and imaging characteristics of this condition, and to report its surgical treatment in a series of 23 adult patients. Epilepsy patients diagnosed with temporal anteroinferior encephalocele from January 2006 to December 2013 in a national epilepsy reference center were included in this noninterventional study. Twenty-three epilepsy patients (14 female, mean age 43.8 years) were diagnosed with temporal anteroinferior encephalocele in our institute. Thirteen patients had ≥2 encephaloceles; 7 cases presented bilaterally. The estimated frequency of this condition was 0.3% among MRI examinations performed due to newly diagnosed epilepsy (n = 6) and 1.9% among drug-resistant patients referred to our center (n = 17). Nine patients with local encephalocele disconnection (n = 4) or anterior temporal lobectomy and amygdalohippocampectomy (n = 5) have become seizure-free (Engel 1) for a mean 2.8 years (range 3 months-6.2 years) of follow-up. Three patients with local encephalocele disconnection were almost seizure-free or exhibited worthwhile improvement. Histologically, all 12 surgical patients had gliosis at the base of the encephalocele; some had cortical laminar disorganization (n = 5) or mild hippocampal degeneration (n = 1). The possibility of a temporal encephalocele should be considered when interpreting MRI examinations of patients with medically intractable focal epilepsy. These patients can significantly benefit from unitemporal epilepsy surgery, even in cases with bilateral encephaloceles. © 2015 American Academy of Neurology.

  8. Age-Dependent Mesial Temporal Lobe Lateralization in Language FMRI

    Science.gov (United States)

    Sepeta, Leigh N.; Berl, Madison M.; Wilke, Marko; You, Xiaozhen; Mehta, Meera; Xu, Benjamin; Inati, Sara; Dustin, Irene; Khan, Omar; Austermuehle, Alison; Theodore, William H.; Gaillard, William D.

    2015-01-01

    Objective FMRI activation of the mesial temporal lobe (MTL) may be important for epilepsy surgical planning. We examined MTL activation and lateralization during language fMRI in children and adults with focal epilepsy. Methods 142 controls and patients with left hemisphere focal epilepsy (Pediatric: epilepsy, n = 17, mean age = 9.9 ± 2.0; controls, n = 48; mean age = 9.1 ± 2.6; Adult: epilepsy, n = 20, mean age = 26.7 ± 5.8; controls, n = 57, mean age = 26.2 ± 7.5) underwent 3T fMRI using a language task (auditory description decision task). Image processing and analyses were conducted in SPM8; ROIs included MTL, Broca’s area, and Wernicke’s area. We assessed group and individual MTL activation, and examined degree of lateralization. Results Patients and controls (pediatric and adult) demonstrated group and individual MTL activation during language fMRI. MTL activation was left lateralized for adults but less so in children (p’s < 0.005). Patients did not differ from controls in either age group. Stronger left-lateralized MTL activation was related to older age (p = 0.02). Language lateralization (Broca’s and Wernicke’s) predicted 19% of the variance in MTL lateralization for adults (p = 0.001), but not children. Significance Language fMRI may be used to elicit group and individual MTL activation. The developmental difference in MTL lateralization and its association with language lateralization suggests a developmental shift in lateralization of MTL function, with increased left lateralization across the age span. This shift may help explain why children have better memory outcomes following resection compared to adults. PMID:26696589

  9. Lateralizing value of semiology in medial temporal lobe epilepsy.

    Science.gov (United States)

    Dupont, S; Samson, Y; Nguyen-Michel, V-H; Zavanone, C; Navarro, V; Baulac, M; Adam, C

    2015-12-01

    Analysing the clinical characteristics of seizures constitutes a fundamental aspect of the presurgical evaluation of patients with medial temporal lobe epilepsy and unilateral hippocampal sclerosis (MTLE-HS), the most frequent form of focal epilepsy accessible to surgery. We sought to retrospectively determine whether objective manifestations could have a reliable lateralizing value in a large population of MTLE-HS patients and if their presence could help to identify those patients who would be seizure free after surgery. We analysed the frequency and predictive lateralizing value of objective ictal and postictal signs in 391 patients with MTLE-HS (183 left/208 right). Data were derived from chart review and not from blinded videoEEG analysis. Correlation between the presence of reliable lateralizing signs and postoperative outcome was performed in a subgroup of 302 patients who underwent surgery. Contralateral dystonic posturing was the most frequent and reliable lateralizing sign that correctly lateralized the focus in 96% of patients. Unilateral head/eye deviation was noted in 42% of the patients and predicted unilateral focus in 67%. Ipsilateral postictal nose wiping, contralateral clonus and hypokinesia correctly lateralized the focus in 75%, 81%, respectively, and 100 of patients but were less frequently depicted. Postictal aphasia was a strong lateralizing sign for left MLE-HS. The presence of reliable lateralizing signs was not a predictor of seizure freedom. Seizure semiology is a simple tool that may permit reliable lateralization of the seizure focus in MTLE-HS. The presence of reliable lateralizing signs is not associated with a better postoperative outcome. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  10. Surgical outcome of MRI-negative refractory extratemporal lobe epilepsy.

    Science.gov (United States)

    Shi, Jianguo; Lacuey, Nuria; Lhatoo, Samden

    2017-07-01

    The aim of this study is to determine outcome of resective epilepsy surgery in MRI-negative extratemporal lobe epilepsy (MNETLE) patients who underwent invasive evaluations and to determine factors governing outcome. We studied 28 patients who underwent resective epilepsy surgery for MNETLE from August 2006 to November 2015, in whom complete follow-up information was available. Electro-clinical, pathological and surgical data were evaluated. 24 patients (82.8%) were explored with intracranial EEG (9 stereoelectroencephalography (SEEG), 7 subdural grids and 8 both). All patients were followed for at least 6 months. During a mean follow up period of 32 [6-113] months, 13 (46.4%) patients became seizure-free (ILAE 1) and 18 (64.3%) had a good (ILAE 1, 2, 3) outcome. 21 (75.0%) patients had focal cortical dysplasia (FCD). Univariate analysis showed that more restricted (regional) interictal and ictal epileptiform discharges in surface EEG were significantly associated with seizure freedom (P=0.016 and P=0.024). Multivariate analysis confirmed that having ≥120 electrode contacts in the evaluation is an independent variable predicting seizure freedom (HR=4.283, 95% CI=1.342-13.676, P=0.014). Invasive EEG is a powerful tool in the pre-surgical evaluation of patients with MNETLE. Invasive EEG implantation that include the irritative zone and EEG onset zone as indicated by surface EEG, as well as wider brain coverage predict seizure freedom, contingent upon a sound anatomo-electro-clinical hypothesis for implantation. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. Chronic deep brain stimulation in mesial temporal lobe epilepsy.

    Science.gov (United States)

    Boëx, Colette; Seeck, Margitta; Vulliémoz, Serge; Rossetti, Andrea O; Staedler, Claudio; Spinelli, Laurent; Pegna, Alan J; Pralong, Etienne; Villemure, Jean-Guy; Foletti, Giovanni; Pollo, Claudio

    2011-07-01

    The objective of this study was to evaluate the efficiency and the effects of changes in parameters of chronic amygdala-hippocampal deep brain stimulation (AH-DBS) in mesial temporal lobe epilepsy (TLE). Eight pharmacoresistant patients, not candidates for ablative surgery, received chronic AH-DBS (130 Hz, follow-up 12-24 months): two patients with hippocampal sclerosis (HS) and six patients with non-lesional mesial TLE (NLES). The effects of stepwise increases in intensity (0-Off to 2 V) and stimulation configuration (quadripolar and bipolar), on seizure frequency and neuropsychological performance were studied. The two HS patients obtained a significant decrease (65-75%) in seizure frequency with high voltage bipolar DBS (≥1 V) or with quadripolar stimulation. Two out of six NLES patients became seizure-free, one of them without stimulation, suggesting a microlesional effect. Two NLES patients experienced reductions of seizure frequency (65-70%), whereas the remaining two showed no significant seizure reduction. Neuropsychological evaluations showed reversible memory impairments in two patients under strong stimulation only. AH-DBS showed long-term efficiency in most of the TLE patients. It is a valuable treatment option for patients who suffer from drug resistant epilepsy and who are not candidates for resective surgery. The effects of changes in the stimulation parameters suggest that a large zone of stimulation would be required in HS patients, while a limited zone of stimulation or even a microlesional effect could be sufficient in NLES patients, for whom the importance of the proximity of the electrode to the epileptogenic zone remains to be studied. Further studies are required to ascertain these latter observations. Copyright © 2011 British Epilepsy Association. Published by Elsevier Ltd. All rights reserved.

  12. A rare case of a bronchial anomaly running in the hilar region from the right lower lobe to the middle lobe.

    Science.gov (United States)

    Fujishita, Takatoshi; Okamoto, Tatsuro; Suzuki, Yuzo; Kitahara, Hirokazu; Shimamatsu, Shinichiro; Kohno, Mikihiro; Morodomi, Yosuke; Kawano, Daigo; Matsuo, Yoshio; Honda, Hiroshi; Maehara, Yoshihiko

    2014-04-01

    A 77-year-old male was referred to our department due to lung cancer (cT3N0M0) of the right lower lobe. During right lower lobectomy, a thin duct structure was recognized in the hilar region between the middle and lower lobes that was identified to be a supernumerary bronchus upon a review of the preoperative chest CT images. Although bronchial anomalies are rare, it is important to carefully view preoperative images for any such anomalies in order to more safely perform surgery.

  13. Two-population model for medial temporal lobe neurons: The vast majority are almost silent.

    Science.gov (United States)

    Magyar, Andrew; Collins, John

    2015-07-01

    Recordings in the human medial temporal lobe have found many neurons that respond to pictures (and related stimuli) of just one particular person of those presented. It has been proposed that these are concept cells, responding to just a single concept. However, a direct experimental test of the concept cell idea appears impossible, because it would need the measurement of the response of each cell to enormous numbers of other stimuli. Here we propose a new statistical method for analysis of the data that gives a more powerful way to analyze how close data are to the concept-cell idea. Central to the model is the neuronal sparsity, defined as the total fraction of stimuli that elicit an above-threshold response in the neuron. The model exploits the large number of sampled neurons to give sensitivity to situations where the average response sparsity is much less than one response for the number of presented stimuli. We show that a conventional model where a single sparsity is postulated for all neurons gives an extremely poor fit to the data. In contrast, a model with two dramatically different populations gives an excellent fit to data from the hippocampus and entorhinal cortex. In the hippocampus, one population has 7% of the cells with a 2.6% sparsity. But a much larger fraction (93%) respond to only 0.1% of the stimuli. This can result in an extreme bias in the responsiveness of reported neurons compared with a typical neuron. Finally, we show how to allow for the fact that some identified units correspond to multiple neurons and find that our conclusions at the neural level are quantitatively changed but strengthened, with an even stronger difference between the two populations.

  14. Automated design system for a rotor with an ellipse lobe profile

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Sung Yuen; Kim Chul [Pusan National University, Busan (Korea, Republic of); Han, Seung Moo [Kyung Hee University, Seoul (Korea, Republic of); Cho, Hae Yong [Chungbuk National University, Cheongju (Korea, Republic of)

    2009-11-15

    An internal lobe pump (ILP) is suitable for machine tool oil hydraulics, automotive engines, compressors, and various other devices. In particular, the ILP is an essential component of an automotive engine, used to feed lubricant oil through the system. The main components of an ILP are its rotors. The outer rotor is typically characterized by lobes with an elliptical shape, and the inner rotor profile is a conjugate to the outer profile. This paper describes a theoretical analysis of an ILP and the development of an integrated automated system for rotor design. This system is composed of three main modules and has been developed using AutoLISP for the AutoCAD program. The system generates a new lobe profile and automatically calculates flow rate and flow rate irregularity according to the lobe profile generated. Results obtained from the analysis can enable oil pump designers and manufacturers to become more efficient

  15. Origin and distribution of the organic matter in the distal lobe of the Congo deep-sea fan - A Rock-Eval survey

    Science.gov (United States)

    Baudin, François; Stetten, Elsa; Schnyder, Johann; Charlier, Karine; Martinez, Philippe; Dennielou, Bernard; Droz, Laurence

    2017-08-01

    The Congo River, the second largest river in the world, is a major source of organic matter for the deep Atlantic Ocean because of the connection of its estuary to the deep offshore area by a submarine canyon which feeds a vast deep-sea fan. The lobe zone of this deep-sea fan is the final receptacle of the sedimentary inputs presently channelled by the canyon and covers an area of 2500 km². The quantity and the source of organic matter preserved in recent turbiditic sediments from the distal lobe of the Congo deep-sea fan were assessed using Rock-Eval pyrolysis analyses. Six sites, located at approximately 5000 m water-depth, were investigated. The mud-rich sediments of the distal lobe contain high amounts of organic matter ( 3.5 to 4% Corg), the origin of which is a mixture of terrestrial higher-plant debris, soil organic matter and deeply oxidized phytoplanktonic material. Although the respective contribution of terrestrial and marine sources of organic matter cannot be precisely quantified using Rock-Eval analyses, the terrestrial fraction is dominant according to similar hydrogen and oxygen indices of both suspended and bedload sediments from the Congo River and that deposited in the lobe complex. The Rock-Eval signature supports the 70% to 80% of the terrestrial fraction previously estimated using C/N and δ13Corg data. In the background sediment, the organic matter distribution is homogeneous at different scales, from a single turbiditic event to the entire lobe, and changes in accumulation rates only have a limited effect on the quantity and quality of the preserved organic matter. Peculiar areas with chemosynthetic bivalves and/or bacterial mats, explored using ROV Victor 6000, show a Rock-Eval signature similar to background sediment. This high organic carbon content associated to high sedimentation rates (> 2 to 20 mm.yr-1) in the Congo distal lobe complex implies a high burial rate for organic carbon. Consequently, the Congo deep-sea fan represents an

  16. Asynchrony in respiratory movements between the pulmonary lobes in patients with COPD: continuous measurement of lung density by 4-dimensional dynamic-ventilation CT

    Directory of Open Access Journals (Sweden)

    Yamashiro T

    2017-07-01

    Full Text Available Tsuneo Yamashiro,1 Hiroshi Moriya,2 Shin Matsuoka,3 Yukihiro Nagatani,4 Maho Tsubakimoto,1 Nanae Tsuchiya,1 Sadayuki Murayama1 On behalf of the ACTIve Study Group 1Department of Radiology, Graduate School of Medical Science, University of the Ryukyus, Nishihara, Okinawa, Japan; 2Department of Radiology, Ohara General Hospital, Fukushima-City, Fukushima, Japan; 3Department of Radiology, St Marianna University School of Medicine, Kawasaki, Kanagawa, Japan; 4Department of Radiology, Shiga University of Medical Science, Otsu, Shiga, Japan Purpose: Four-dimensional dynamic-ventilation CT imaging demonstrates continuous movement of the lung. The aim of this study was to assess the correlation between interlobar synchrony in lung density and spirometric values in COPD patients and smokers, by measuring the continuous changes in lung density during respiration on the dynamic-ventilation CT. Materials and methods: Thirty-two smokers, including ten with COPD, underwent dynamic-ventilation CT during free breathing. CT data were continuously reconstructed every 0.5 sec. Mean lung density (MLD of the five lobes (right upper [RU], right middle [RM], right lower [RL], left upper [LU], and left lower [LL] was continuously measured by commercially available software using a fixed volume of volume of interest which was placed and tracked on a single designated point in each lobe. Concordance between the MLD time curves of six pairs of lung lobes (RU-RL, RU-RM, RM-RL, LU-LL, RU-LU, and RL-LL lobes was expressed by cross-correlation coefficients. The relationship between these cross-correlation coefficients and the forced expiratory volume in one second/forced vital capacity (FEV1.0/FVC values was assessed by Spearman rank correlation analysis. Results: In all six pairs of the pulmonary lobes, the cross-correlation coefficients of the two MLD curves were significantly positively correlated with FEV1.0/FVC (ρ =0.60–0.73, P<0.001. The mean value of the six

  17. A review of sorption of radionuclides under the near- and far-field conditions of an underground radioactive waste repository. Pt. 1

    International Nuclear Information System (INIS)

    Berry, J.A.

    1992-01-01

    This report presents and discusses work funded by the Department of the Environment and UK Nirex Ltd in the area of sorption of radionuclides under near-field and far-field conditions as related to the underground disposal of radioactive waste in the UK. It is intended as a basis for comparison with work undertaken world-wide in the sorption area, presented in Part II of this review. The UK and overseas work are compared in Part III. From lists of reports and papers supplied by DOE (HMIP) and Nirex, those publications believed to be relevant were selected and are listed here by subject. Summaries of all these reports are included in the form of abstracts, or where available, executive summaries. The work presented is further summarised and discussed. Sections on sorption and laboratory experimental methods are included, along with a section on the level of understanding and outstanding issues. (Author)

  18. Far-field dynamic behavior of a half-space under an inertial strip foundation subjected to a time-harmonic force

    Directory of Open Access Journals (Sweden)

    M. Dehestani

    Full Text Available Recent research works demonstrated that the interaction between the loads and the carrying structure's boundary which is related to the inertia of the load is an influential factor on the dynamic response of the structure. Although effects of the inertia in moving loads were considered in many works, very few papers can be found on the inertial effects of the stationary loads on structures. In this paper, an elastodynamic formulation was employed to investigate the dynamic response of a homogeneous isotropic elastic half-space under an inertial strip foundation subjected to a time-harmonic force. Fourier integral transformation was used to solve the system of Poisson-type partial differential equation considering the boundary conditions and the inertial effects. Steepest descent method was employed to obtain the approximate far-field displacements and stresses. A numerical example is presented to illustrate the methodology and typical results.

  19. Consistency of the directionality of partially coherent beams in turbulence expressed in terms of the angular spread and the far-field average intensity

    International Nuclear Information System (INIS)

    Xiao-Wen, Chen; Xiao-Ling, Ji

    2010-01-01

    Under the quadratic approximation of the Rytov's phase structure function, this paper derives the general closed-form expressions for the mean-squared width and the angular spread of partially coherent beams in turbulence. It finds that under a certain condition different types of partially coherent beams may have the same directionality as a fully coherent Gaussian beam in free space and also in atmospheric turbulence if the angular spread is chosen as the characteristic parameter of beam directionality. On the other hand, it shows that generally, the directionality of partially coherent beams expressed in terms of the angular spread is not consistent with that in terms of the normalized far-field average intensity distribution in free space, but the consistency can be achieved due to turbulence. (classical areas of phenomenology)

  20. Pulmonary lobe segmentation based on ridge surface sampling and shape model fitting

    International Nuclear Information System (INIS)

    Ross, James C.; Kindlmann, Gordon L.; Okajima, Yuka; Hatabu, Hiroto; Díaz, Alejandro A.; Silverman, Edwin K.; Washko, George R.; Dy, Jennifer; Estépar, Raúl San José

    2013-01-01

    Purpose: Performing lobe-based quantitative analysis of the lung in computed tomography (CT) scans can assist in efforts to better characterize complex diseases such as chronic obstructive pulmonary disease (COPD). While airways and vessels can help to indicate the location of lobe boundaries, segmentations of these structures are not always available, so methods to define the lobes in the absence of these structures are desirable. Methods: The authors present a fully automatic lung lobe segmentation algorithm that is effective in volumetric inspiratory and expiratory computed tomography (CT) datasets. The authors rely on ridge surface image features indicating fissure locations and a novel approach to modeling shape variation in the surfaces defining the lobe boundaries. The authors employ a particle system that efficiently samples ridge surfaces in the image domain and provides a set of candidate fissure locations based on the Hessian matrix. Following this, lobe boundary shape models generated from principal component analysis (PCA) are fit to the particles data to discriminate between fissure and nonfissure candidates. The resulting set of particle points are used to fit thin plate spline (TPS) interpolating surfaces to form the final boundaries between the lung lobes. Results: The authors tested algorithm performance on 50 inspiratory and 50 expiratory CT scans taken from the COPDGene study. Results indicate that the authors' algorithm performs comparably to pulmonologist-generated lung lobe segmentations and can produce good results in cases with accessory fissures, incomplete fissures, advanced emphysema, and low dose acquisition protocols. Dice scores indicate that only 29 out of 500 (5.85%) lobes showed Dice scores lower than 0.9. Two different approaches for evaluating lobe boundary surface discrepancies were applied and indicate that algorithm boundary identification is most accurate in the vicinity of fissures detectable on CT. Conclusions: The proposed

  1. Pulmonary lobe segmentation based on ridge surface sampling and shape model fitting

    Energy Technology Data Exchange (ETDEWEB)

    Ross, James C., E-mail: jross@bwh.harvard.edu [Channing Laboratory, Brigham and Women' s Hospital, Boston, Massachusetts 02215 (United States); Surgical Planning Lab, Brigham and Women' s Hospital, Boston, Massachusetts 02215 (United States); Laboratory of Mathematics in Imaging, Brigham and Women' s Hospital, Boston, Massachusetts 02126 (United States); Kindlmann, Gordon L. [Computer Science Department and Computation Institute, University of Chicago, Chicago, Illinois 60637 (United States); Okajima, Yuka; Hatabu, Hiroto [Department of Radiology, Brigham and Women' s Hospital, Boston, Massachusetts 02215 (United States); Díaz, Alejandro A. [Pulmonary and Critical Care Division, Brigham and Women' s Hospital and Harvard Medical School, Boston, Massachusetts 02215 and Department of Pulmonary Diseases, Pontificia Universidad Católica de Chile, Santiago (Chile); Silverman, Edwin K. [Channing Laboratory, Brigham and Women' s Hospital, Boston, Massachusetts 02215 and Pulmonary and Critical Care Division, Brigham and Women' s Hospital and Harvard Medical School, Boston, Massachusetts 02215 (United States); Washko, George R. [Pulmonary and Critical Care Division, Brigham and Women' s Hospital and Harvard Medical School, Boston, Massachusetts 02215 (United States); Dy, Jennifer [ECE Department, Northeastern University, Boston, Massachusetts 02115 (United States); Estépar, Raúl San José [Department of Radiology, Brigham and Women' s Hospital, Boston, Massachusetts 02215 (United States); Surgical Planning Lab, Brigham and Women' s Hospital, Boston, Massachusetts 02215 (United States); Laboratory of Mathematics in Imaging, Brigham and Women' s Hospital, Boston, Massachusetts 02126 (United States)

    2013-12-15

    Purpose: Performing lobe-based quantitative analysis of the lung in computed tomography (CT) scans can assist in efforts to better characterize complex diseases such as chronic obstructive pulmonary disease (COPD). While airways and vessels can help to indicate the location of lobe boundaries, segmentations of these structures are not always available, so methods to define the lobes in the absence of these structures are desirable. Methods: The authors present a fully automatic lung lobe segmentation algorithm that is effective in volumetric inspiratory and expiratory computed tomography (CT) datasets. The authors rely on ridge surface image features indicating fissure locations and a novel approach to modeling shape variation in the surfaces defining the lobe boundaries. The authors employ a particle system that efficiently samples ridge surfaces in the image domain and provides a set of candidate fissure locations based on the Hessian matrix. Following this, lobe boundary shape models generated from principal component analysis (PCA) are fit to the particles data to discriminate between fissure and nonfissure candidates. The resulting set of particle points are used to fit thin plate spline (TPS) interpolating surfaces to form the final boundaries between the lung lobes. Results: The authors tested algorithm performance on 50 inspiratory and 50 expiratory CT scans taken from the COPDGene study. Results indicate that the authors' algorithm performs comparably to pulmonologist-generated lung lobe segmentations and can produce good results in cases with accessory fissures, incomplete fissures, advanced emphysema, and low dose acquisition protocols. Dice scores indicate that only 29 out of 500 (5.85%) lobes showed Dice scores lower than 0.9. Two different approaches for evaluating lobe boundary surface discrepancies were applied and indicate that algorithm boundary identification is most accurate in the vicinity of fissures detectable on CT. Conclusions: The

  2. Gangliogliomas: characteristic imaging findings and role in the temporal lobe epilepsy

    International Nuclear Information System (INIS)

    Adachi, Y.; Yagishita, A.

    2008-01-01

    Ganglioglioma is an uncommon neoplasm of the central nervous system, most frequently seen in the temporal lobe, and usually associated with medically refractory epilepsy in children and young adults. Few reports have considered ganglioglioma-associated epileptogenicity arising in the temporal lobe. The purpose of our study was to define the imaging features of ganglioglioma in the temporal lobe and their relation to the seizure foci revealed by electrocorticograms. We reviewed 24 patients with pathologically confirmed ganglioglioma in the temporal lobe. Computed tomography (CT) images showed gangliogliomas to be isodense (91.7%), and on T1-weighted images (T1-WI) most gangliogliomas (79.2%) were isointense to the gray matter. A cystic lesion was seen in 14 of 24 of the gangliogliomas (58.3%). Mass effects were not seen in any of the ten tumors without cystic components. One patient showed tumor recurrence. Dual pathology was seen in two cases (8.3%). In 23 cases, epileptogenicity was confirmed in the tumors by intraoperative electrocorticogram. The remaining case had no epileptogenicity. A tumor presenting isointensity to gray matter on T1-WI without mass effects in the medial temporal lobe in a young patient with temporal lobe epilepsy (TLE) might be the characteristic imaging of temporal lobe ganglioglioma. However, such tumors are not always associated with epileptogenicity, even if a ganglioglioma is found in a patient with TLE. The seizure foci may be contralateral to the ganglioglioma. Therefore, we need to investigate the hippocampus, white matter abnormalities of the ipsilateral and contralateral anterior temporal lobe, and other focal lesions closely. (orig.)

  3. Computed tomography imaging of the pyramidal lobe of the thyroid gland

    International Nuclear Information System (INIS)

    Luis Heber Ulloa Guerrero, Octavio de Jesus Arevalo Espejo

    2011-01-01

    The pyramidal lobe of the thyroid gland is a normal anatomical variant found frequently in the general population. This structure consists of normal thyroid tissue located in the upper part of the thyroid isthmus, extending upward in the form of a fibrous chord that connects it to the foramen caecum at the bottom of the tongue. This paper reviews thyroid anatomy and embryology, and highlights the main features of the pyramidal lobe, including the anatomy, epidemiology and computed tomography imaging.

  4. Exercise-induced seizures and lateral asymmetry in patients with temporal lobe epilepsy

    Directory of Open Access Journals (Sweden)

    Jordan T. Kamel

    2014-01-01

    Conclusions: Exercise may be an underrecognized form of reflex epilepsy, which tended to be refractory to both medical and surgical interventions in our patients. Almost all patients in our cohort had seizures localizing to the left temporal lobe. We discuss potential mechanisms by which exercise may precipitate seizures, and its relevance regarding our understanding of temporal lobe epilepsy and lateralization of seizures. Recognition of, as well as advice regarding avoidance of, known triggers forms an important part of management of these patients.

  5. Lateral chest radiographic findings in lobar collapse of the left lung : the distance between both upper lobe bronchi

    International Nuclear Information System (INIS)

    Chin, G. H.; Sung, D. W.; Yoon, Y.; Kim, H. C.

    1996-01-01

    To evaluate the distance between both upper love bronchi on lateral radiographs and its change in left upper or lower lobe collapse. 144 true lateral radiographs were analyzed on which both upper lobe bronchi were clearly identified. They included 116 normal cases, 11 cases of left upper lobe collapse, 13 of left lower lobe collapse, and 4 cases of left lower lobe lobectomy. Line A was drawn parallel to the vertebral end plate through the upper margin of the lift upper lobe bronchus. Line B was drawn parallel to line A through the upper margin of the right upper love bronchus. The shortest distance between line A and line B was measured as the distance between both upper lobe bronchi. In normal cases, the mean value of the distance was 2.19 cm ± S.D. 0.37 cm on right and on right and 2.16 cm ± S.D. 0.40 cm on left lateral radiographs ; these results were not significantly different(P=0.79). In cases of collapse, the mean value of the distance was 0.43 cm ± S.D. 0.99 cm in upper lobe collapse and 3.56 cm ± S.D. 0.72 cm in lower lobe collapse, results which were significantly different from those of normal cases(p<0.01). In eight cases(73%) of left upper lobe collapse, the distance was less than 1 cm and in 10 cases(77%) of left lower lobe collapse, the distance was more than 3 cm. The distance between both upper lobe bronchi varies markedly in case of lobar collapse. A distance of less than 1 cm suggests collapse of the left upper lobe and a distance more than 3 cm suggests collapse of the left lower lobe

  6. Morphological and immunohistochemical comparison of three rat prostate lobes (lateral, dorsal and ventral in experimental hyperprolactinemia.

    Directory of Open Access Journals (Sweden)

    Dariusz Gącarzewicz

    2010-11-01

    Full Text Available The prolactin plays an important role in the regulation of growth and differentiation of prostate gland besides androgens. The goal of this study was to reveal the influence of elevated prolactin concentration on epithelial cells of prostate. We compared the morphology of epithelial cells of prostate dorsal, lateral and ventral lobes and expression of androgen receptors in these cells in rats with hyperprolactinemia and in control rats. We used sexually mature male Wistar rats. The experimental rats received metoclopramide; the control group received saline in the same way. The prostate dorsal, lateral and ventral lobes were collected routinely for light and electron microscopy. The intensity of immunohistochemical reaction of androgen receptor in epithelial cells of dorsal, lateral and ventral lobes was evaluated by measure of optical density with computer image analysis. The light and electron (transmission and scanning microscopes were used for morphological observations. Results: In experimental rats twofold increase in prolactin and twofold decrease in testosterone found. In experimental group the expression of androgen receptor was lower in columnar epithelial cells of dorsal and ventral lobes but higher in lateral one. We observed morphological abnormalities in columnar epithelial cells of lateral and dorsal lobes. The columnar epithelial cells of ventral lobes didn't show any morphological changes in hyperprolactinemia.

  7. Frontal lobe function in elderly patients with Alzheimer's disease and caregiver burden.

    Science.gov (United States)

    Hashimoto, Akiko; Matsuoka, Kiwamu; Yasuno, Fumihiko; Takahashi, Masato; Iida, Junzo; Jikumaru, Kiyoko; Kishimoto, Toshifumi

    2017-07-01

    Understanding of the relationship between caregiver burden and the degree of behavioural deficits in patients with Alzheimer's disease (AD) is relatively limited. Therefore, it is worthwhile to examine the correlations between the various relevant factors to improve the efficacy of care for patients with AD. The aim of this study was to investigate the specific contributions of frontal lobe dysfunction in AD patients to caregiver burden, while controlling for other predictor variables. Participants included 30 pairs of caregivers and patients with AD. The Zarit Burden Interview and Frontal Assessment Battery were used to measure the caregiver burden and patients' frontal lobe function, respectively. To investigate the effects of frontal lobe dysfunction on caregiver burden, hierarchical regression equations with steps incorporating additional predictor variables were fitted. We also performed a correlation analysis between the individual subdomains of the Zarit Burden Interview and the predictor variables. Our study suggests that the degree of frontal lobe dysfunction in AD patients predicts their caregiver burden, when other factors of daily functional limitations and neuropsychiatric symptoms are controlled. Daily functional limitations and neuropsychiatric symptoms affected caregivers' psychosocial burden, whereas frontal lobe dysfunction affected caregivers' burden due to the increase in the dependency of the patients. Our findings indicate that to ameliorate the disabilities of patients and reduce caregiver burden, there is a need for interventions that focus on psychosocial burdens, as shown in previous studies, as well as on excessive dependency due to frontal lobe dysfunction. © 2017 Japanese Psychogeriatric Society.

  8. Dissociation between Conceptual and Perceptual Implicit Memory: Evidence from Patients with Frontal and Occipital Lobe Lesions

    Science.gov (United States)

    Gong, Liang; Wang, JiHua; Yang, XuDong; Feng, Lei; Li, Xiu; Gu, Cui; Wang, MeiHong; Hu, JiaYun; Cheng, Huaidong

    2016-01-01

    The latest neuroimaging studies about implicit memory (IM) have revealed that different IM types may be processed by different parts of the brain. However, studies have rarely examined what subtypes of IM processes are affected in patients with various brain injuries. Twenty patients with frontal lobe injury, 25 patients with occipital lobe injury, and 29 healthy controls (HC) were recruited for the study. Two subtypes of IM were investigated by using structurally parallel perceptual (picture identification task) and conceptual (category exemplar generation task) IM tests in the three groups, as well as explicit memory (EM) tests. The results indicated that the priming of conceptual IM and EM tasks in patients with frontal lobe injury was poorer than that observed in HC, while perceptual IM was identical between the two groups. By contrast, the priming of perceptual IM in patients with occipital lobe injury was poorer than that in HC, whereas the priming of conceptual IM and EM was similar to that in HC. This double dissociation between perceptual and conceptual IM across the brain areas implies that occipital lobes may participate in perceptual IM, while frontal lobes may be involved in processing conceptual memory. PMID:26793093

  9. [Planning disorders in men with schizophrenia and in men with localized frontal lobe lesions].

    Science.gov (United States)

    Okruszek, Łukasz; Rutkowska, Aleksandra

    2013-01-01

    Planning disorders have been observed in people with frontal lobe lesions for many decades. There's also growing body of evidence of frontal dysfunction in people with schizophrenia. The aim of this study is to compare the planning abilities in men with schizophrenia, men with localized frontal lobe lesions and healthy men. A sample of 90 men participated in the study. They were divided into three groups: men with schizophrenia (n = 30), men with localized frontal lobe lesions (n = 30) and healthy men (n = 30) as a control group. Planning abilities were assessed with a clinical trial based on Tower of London task. Significant differences in ToL measures were found between controls and men with schizophrenia (Trials solved: p frontal lobe lesions (Trials solved: p frontal lobe lesion groups. Similar deficits in planning and solving problems, which require planning, may be observed in men with schizophrenia and men with frontal lobe lesions. In both groups time spent on thinking is less effective than in healthy men. Not only quantitative, but also qualitative assessment should be carried when examining patients' performance on Tower of London task.

  10. argos Is required for projection of photoreceptor axons during optic lobe development in Drosophila.

    Science.gov (United States)

    Sawamoto, K; Okabe, M; Tanimura, T; Hayashi, S; Mikoshiba, K; Okano, H

    1996-02-01

    The Drosophila argos gene encodes a secreted protein with an epidermal growth factor (EGF) motif, which acts as an inhibitor of cell recruitment in the developing eye and wing. Here, we have analyzed the role of argos during optic lobe development. argos expression was observed in the optic lobes throughout the developmental stages. In argos mutants, neuropiles failed to develop normally during embryonic and larval stages, and photoreceptor axons did not project properly into the lamina. Ubiquitous expression of argos, under control of the hsp70 promoter, rescued the defects in optic lobes. We have found that glial cells failed to differentiate in the larval optic lobes of argos mutants. Correspondingly, in loss-of-function repo mutants, whose glial cells also fail to differentiate, photoreceptor axons showed the impaired projection pattern similar to the argos phenotype. These results suggest that glial cells play a role for guidance of photoreceptor axons. The loss-of-function Star mutation (StarX155) dominantly suppressed the defects in the argos optic lobes, suggesting that these two genes act in an antagonistic fashion during optic lobe development.

  11. Decreased left temporal lobe volume of panic patients measured by magnetic resonance imaging

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    R.R. Uchida

    2003-07-01

    Full Text Available Reported neuroimaging studies have shown functional and morphological changes of temporal lobe structures in panic patients, but only one used a volumetric method. The aim of the present study was to determine the volume of temporal lobe structures in patients with panic disorder, measured by magnetic resonance imaging. Eleven panic patients and eleven controls matched for age, sex, handedness, socioeconomic status and years of education participated in the study. The mean volume of the left temporal lobe of panic patients was 9% smaller than that of controls (t21 = 2.37, P = 0.028. In addition, there was a trend (P values between 0.05 and 0.10 to smaller volumes of the right temporal lobe (7%, t21 = 1.99, P = 0.06, right amygdala (8%, t21 = 1.83, P = 0.08, left amygdala (5%, t21 = 1.78, P = 0.09 and left hippocampus (9%, t21 = 1.93, P = 0.07 in panic patients compared to controls. There was a positive correlation between left hippocampal volume and duration of panic disorder (r = 0.67, P = 0.025, with recent cases showing more reduction than older cases. The present results show that panic patients have a decreased volume of the left temporal lobe and indicate the presence of volumetric abnormalities of temporal lobe structures.

  12. Decreased left temporal lobe volume of panic patients measured by magnetic resonance imaging

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    Uchida, R.R.; Del-Ben, C.M.; Araujo, D.; Crippa, J.A.; Graeff, F.G. [Sao Paulo Univ., Ribeirao Preto, SP (Brazil). Dept. de Neurologia e Psicologia Medica]. E-mail: fgraeff@keynet.com.br; Santos, A.C. [Sao Paulo Univ., Ribeirao Preto, SP (Brazil). Dept. de Clinica Medica; Guimaraes, F.S. [Sao Paulo Univ., Ribeirao Preto, SP (Brazil). Dept. de Farmacologia

    2003-07-01

    Reported neuroimaging studies have shown functional and morphological changes of temporal lobe structures in panic patients, but only one used a volumetric method. The aim of the present study was to determine the volume of temporal lobe structures in patients with panic disorder, measured by magnetic resonance imaging. Eleven panic patients and eleven controls matched for age, sex, handedness, socioeconomic status and years of education participated in the study. The mean volume of the left temporal lobe of panic patients was 9% smaller than that of controls (t{sub 21} = 2.37, P = 0.028). In addition, there was a trend (P values between 0.05 and 0.10) to smaller volumes of the right temporal lobe (7%, t{sub 21} = 1.99, P = 0.06), right amygdala (8%, t{sub 21} = 1.83, P = 0.08), left amygdala (5%, t{sub 21} = 1.78, P 0.09) and left hippocampus (9%, t{sub 21} = 1.93, P = 0.07) in panic patients compared to controls. There was a positive correlation between left hippocampal volume and duration of panic disorder (r = 0.67, P = 0.025), with recent cases showing more reduction than older cases. The present results show that panic patients have a decreased volume of the left temporal lobe and indicate the presence of volumetric abnormalities of temporal lobe structures. (author)

  13. Decreased left temporal lobe volume of panic patients measured by magnetic resonance imaging

    International Nuclear Information System (INIS)

    Uchida, R.R.; Del-Ben, C.M.; Araujo, D.; Crippa, J.A.; Graeff, F.G.; Santos, A.C.; Guimaraes, F.S.

    2003-01-01

    Reported neuroimaging studies have shown functional and morphological changes of temporal lobe structures in panic patients, but only one used a volumetric method. The aim of the present study was to determine the volume of temporal lobe structures in patients with panic disorder, measured by magnetic resonance imaging. Eleven panic patients and eleven controls matched for age, sex, handedness, socioeconomic status and years of education participated in the study. The mean volume of the left temporal lobe of panic patients was 9% smaller than that of controls (t 21 = 2.37, P = 0.028). In addition, there was a trend (P values between 0.05 and 0.10) to smaller volumes of the right temporal lobe (7%, t 21 = 1.99, P = 0.06), right amygdala (8%, t 21 = 1.83, P = 0.08), left amygdala (5%, t 21 = 1.78, P 0.09) and left hippocampus (9%, t 21 = 1.93, P = 0.07) in panic patients compared to controls. There was a positive correlation between left hippocampal volume and duration of panic disorder (r = 0.67, P = 0.025), with recent cases showing more reduction than older cases. The present results show that panic patients have a decreased volume of the left temporal lobe and indicate the presence of volumetric abnormalities of temporal lobe structures. (author)

  14. Cortical Activation during a Cognitive Challenge in Patients with Chronic Temporal Lobe Epilepsy—A Dynamic SPECT Study

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    P. J. Kirkpatrick

    1993-01-01

    Full Text Available In a pilot group of six patients suffering from chronic temporal lobe epilepsy, single photon emission computerized tomography (SPECT has been used to image the changes in relative cerebral blood flow between rest (static scan and conditions of cognitive activation (activated scan. The cognitive challenge used during activation comprised a test of word memory, and the performance was expressed as a word memory score (WMS for each individual. An activation index (AI was calculated from the mean normalized density counts in specific regions of interest (ROIs, and values obtained were analysed for correlation with the WMS. The mean AI was increased significantly in the right lateral temporal cortex, the right and left inferior frontal regions, the left temporal pole, and the right medial temporal cortex. A positive correlation with the WMS was found in the medial temporal cortices, and this relationship was significant for the right medial temporal ROI.

  15. Feasibility of the Medial Temporal lobe Atrophy index (MTAi and derived methods for measuring atrophy of the medial temporal lobe

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    Francisco eConejo Bayón

    2014-11-01

    Full Text Available Introduction: the Medial Temporal-lobe Atrophy index (MTAi, 2D-Medial Temporal Atrophy (2D-MTA, yearly rate of MTA (yrRMTA and yearly rate of relative MTA (yrRMTA are simple protocols for measuring the relative extent of atrophy in the MTL in relation to the global brain atrophy. Albeit preliminary studies showed interest of these methods in the diagnosis of AD, FTLD and correlation with cognitive impairment in PD, formal feasibility and validity studies remained pending. As a first step, we aimed to assess the feasibility. Mainly, we aimed to assess the reproducibility of measuring the areas needed to compute these indices. We also aimed to assess the efforts needed to start using these methods correctly. Methods: a series of 290 1.5T-MRI studies from 230 subjects ranging 65-85 years old who had been studied for cognitive impairment were used in this study. Six inexperienced tracers (IT plus one experienced tracer (ET traced the three areas needed to compute the indices. Finally, tracers underwent a short survey on their experience learning to compute the MTAi and experience of usage, including items relative to training time needed to understand and apply the MTAi, time to perform a study after training and overall satisfaction. Results: learning to trace the areas needed to compute the MTAi and derived methods is quick and easy. Results indicate very good intrarater ICC for the MTAi, good intrarater ICC for the 2D-MTA, yrMTA and yrRMTA and also good interrater ICC for the MTAi, 2D-MTA, yrMTA and yrRMTA.Conclusion: our data support that MTAi and derived methods (2D-MTA, yrMTA and yrRTMA have good to very good intrarater and interrater reproducibility and may be easily implemented in clinical practice even if new users have no experience tracing the area of regions of interest.

  16. Graft-to-recipient weight ratio lower to 0.7% is safe without portal pressure modulation in right-lobe living donor liver transplantation with favorable conditions.

    Science.gov (United States)

    Lee, Seung Duk; Kim, Seong Hoon; Kim, Young-Kyu; Lee, Soon-Ae; Park, Sang-Jae

    2014-02-01

    The low graft-to-recipient weight ratio (GRWR) in adult-to-adult living donor liver transplantation (LDLT) is one of the major risk factors affecting graft survival. The goal of this study was to evaluate whether the lower limit of the GRWR can be safely reduced without portal pressure modulation in right-lobe LDLT. From 2005 to 2011, 317 consecutive patients from a single institute underwent LDLT with right-lobe grafts without portal pressure modulation. Of these, 23 had a GRWR of less than 0.7% (group A), 27 had a GRWR of ≥0.7%, recipient, donor, operation factors, laboratory findings and complications were reviewed retrospectively. The baseline demographics showed low model for end-stage liver disease score (mean 16.3+/-8.9) and high percentage of hepatocellular carcinoma (231 patients, 72.9%). Three groups by GRWR demonstrated similar characteristics except recipient body mass index and donor gender. For small-for-size syndrome, there were 3 (13.0%) in group A, 1 (3.7%) in group B, and 2 patients (0.7%) in group C (Pneed to modulate portal pressure in adult-to-adult LDLT using the right-lobe in favorable conditions including low model for end-stage liver disease score.

  17. Temporal features of spike trains in the moth antennal lobe revealed by a comparative time-frequency analysis.

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    Alberto Capurro

    Full Text Available The discrimination of complex sensory stimuli in a noisy environment is an immense computational task. Sensory systems often encode stimulus features in a spatiotemporal fashion through the complex firing patterns of individual neurons. To identify these temporal features, we have developed an analysis that allows the comparison of statistically significant features of spike trains localized over multiple scales of time-frequency resolution. Our approach provides an original way to utilize the discrete wavelet transform to process instantaneous rate functions derived from spike trains, and select relevant wavelet coefficients through statistical analysis. Our method uncovered localized features within olfactory projection neuron (PN responses in the moth antennal lobe coding for the presence of an odor mixture and the concentration of single component odorants, but not for compound identities. We found that odor mixtures evoked earlier responses in biphasic response type PNs compared to single components, which led to differences in the instantaneous firing rate functions with their signal power spread across multiple frequency bands (ranging from 0 to 45.71 Hz during a time window immediately preceding behavioral response latencies observed in insects. Odor concentrations were coded in excited response type PNs both in low frequency band differences (2.86 to 5.71 Hz during the stimulus and in the odor trace after stimulus offset in low (0 to 2.86 Hz and high (22.86 to 45.71 Hz frequency bands. These high frequency differences in both types of PNs could have particular relevance for recruiting cellular activity in higher brain centers such as mushroom body Kenyon cells. In contrast, neurons in the specialized pheromone-responsive area of the moth antennal lobe exhibited few stimulus-dependent differences in temporal response features. These results provide interesting insights on early insect olfactory processing and introduce a novel

  18. Longer epilepsy duration and multiple lobe involvement predict worse seizure outcomes for patients with refractory temporal lobe epilepsy associated with neurocysticercosis

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    Lucas Crociati Meguins

    2015-12-01

    Full Text Available ABSTRACT Objective To investigate the surgical outcomes of temporal lobe epilepsy associated with hippocampal sclerosis (TLE-HS and neurocysticercosis (NCC. Methods A retrospective investigation of patients with TLE-HS was conducted in a tertiary center. Results Seventy-nine (62.2%, 37 (29.1%, 6 (4.7%, and 5 (3.9% patients were Engel class I, II, III, and IV, respectively. Fifty-two (71.2% patients with epilepsy durations ≤ 10 years prior to surgery were seizure-free 1 year after the operation compared to 27 (50.0% patients with epilepsy durations > 10 years (p = 0.0121. Forty-three (72.9% patients with three or fewer lobes affected by NCC were seizure-free one year after the operation, and 36 (52.9% patients with more than three involved lobes were seizure-free after surgery (p = 0.0163. Conclusions Longer epilepsy durations and multiple lobe involvement predicted worse seizure outcomes in TLE-HS plus NCC patients.

  19. Acoustic and Laser Doppler Anemometer Results for Confluent, 22-Lobed, and Unique-Lobed Mixer Exhaust Systems for Subsonic Jet Noise Reduction

    Science.gov (United States)

    Salikuddin, M.; Martens, S.; Shin, H.; Majjigi, R. K.; Krejsa, Gene (Technical Monitor)

    2002-01-01

    The objective of this task was to develop a design methodology and noise reduction concepts for high bypass exhaust systems which could be applied to both existing production and new advanced engine designs. Special emphasis was given to engine cycles with bypass ratios in the range of 4:1 to 7:1, where jet mixing noise was a primary noise source at full power takeoff conditions. The goal of this effort was to develop the design methodology for mixed-flow exhaust systems and other novel noise reduction concepts that would yield 3 EPNdB noise reduction relative to 1992 baseline technology. Two multi-lobed mixers, a 22-lobed axisymmetric and a 21-lobed with a unique lobe, were designed. These mixers along with a confluent mixer were tested with several fan nozzles of different lengths with and without acoustic treatment in GEAE's Cell 41 under the current subtask (Subtask C). In addition to the acoustic and LDA tests for the model mixer exhaust systems, a semi-empirical noise prediction method for mixer exhaust system is developed. Effort was also made to implement flowfield data for noise prediction by utilizing MGB code. In general, this study established an aero and acoustic diagnostic database to calibrate and refine current aero and acoustic prediction tools.

  20. Isolated amygdala enlargement in temporal lobe epilepsy: A systematic review.

    Science.gov (United States)

    Beh, S M Jessica; Cook, Mark J; D'Souza, Wendyl J

    2016-07-01

    The objective of this study was to compare the seizure characteristics and treatment outcomes in patient groups with temporal lobe epilepsy (TLE) identified with isolated amygdala enlargement (AE) on magnetic resonance imaging studies. PubMed, Embase, and the Cochrane Library were searched for relevant studies using the keywords 'amygdala enlargement', 'epilepsy', and 'seizures' in April 2015. Human studies, written in English, that investigated cohorts of patients with TLE and AE were included. Of 204 abstracts initially identified using the search strategy, 14 studies met the inclusion criteria (11 epilepsy studies and 3 psychiatry studies). Ultimately, 8 full studies on AE and TLE involving 107 unique patients were analyzed. Gender distribution consisted of 50 males and 57 females. Right amygdala enlargement was seen in 39 patients, left enlargement in 58 patients, and bilateral enlargement in 7 patients. Surgical resection was performed in 28 patients, with the most common finding being dysplasia/hamartoma or focal cortical dysplasia. Most studies involved small samples of less than 12 patients. There was a wide discrepancy in the methods used to measure amygdala volume, in both patients and controls, hindering comparisons. Most TLE with AE studies observed a later age of seizure onset (mean: 32.2years) compared with studies involving TLE with HS (mean of mid- to late childhood). A higher frequency of complex partial seizures compared with that of convulsive seizures is seen in patients with AE (67-100% vs. 26-47%), and they have an excellent response to antiepileptic drugs (81.8%-100% of seizure-free patients). All studies that included controls also found a significant difference in frequency of seizure types between their cases and controls. Reliable assessment of amygdala volume remains a critical issue hindering better understanding of the clinical management and research of this focal epilepsy syndrome. Within these limitations, the literature suggests

  1. Lateralization of mesial temporal lobe epilepsy with chronic ambulatory electrocorticography.

    Science.gov (United States)

    King-Stephens, David; Mirro, Emily; Weber, Peter B; Laxer, Kenneth D; Van Ness, Paul C; Salanova, Vicenta; Spencer, David C; Heck, Christianne N; Goldman, Alica; Jobst, Barbara; Shields, Donald C; Bergey, Gregory K; Eisenschenk, Stephan; Worrell, Gregory A; Rossi, Marvin A; Gross, Robert E; Cole, Andrew J; Sperling, Michael R; Nair, Dileep R; Gwinn, Ryder P; Park, Yong D; Rutecki, Paul A; Fountain, Nathan B; Wharen, Robert E; Hirsch, Lawrence J; Miller, Ian O; Barkley, Gregory L; Edwards, Jonathan C; Geller, Eric B; Berg, Michel J; Sadler, Toni L; Sun, Felice T; Morrell, Martha J

    2015-06-01

    Patients with suspected mesial temporal lobe (MTL) epilepsy typically undergo inpatient video-electroencephalography (EEG) monitoring with scalp and/or intracranial electrodes for 1 to 2 weeks to localize and lateralize the seizure focus or foci. Chronic ambulatory electrocorticography (ECoG) in patients with MTL epilepsy may provide additional information about seizure lateralization. This analysis describes data obtained from chronic ambulatory ECoG in patients with suspected bilateral MTL epilepsy in order to assess the time required to determine the seizure lateralization and whether this information could influence treatment decisions. Ambulatory ECoG was reviewed in patients with suspected bilateral MTL epilepsy who were among a larger cohort with intractable epilepsy participating in a randomized controlled trial of responsive neurostimulation. Subjects were implanted with bilateral MTL leads and a cranially implanted neurostimulator programmed to detect abnormal interictal and ictal ECoG activity. ECoG data stored by the neurostimulator were reviewed to determine the lateralization of electrographic seizures and the interval of time until independent bilateral MTL electrographic seizures were recorded. Eighty-two subjects were implanted with bilateral MTL leads and followed for 4.7 years on average (median 4.9 years). Independent bilateral MTL electrographic seizures were recorded in 84%. The average time to record bilateral electrographic seizures in the ambulatory setting was 41.6 days (median 13 days, range 0-376 days). Sixteen percent had only unilateral electrographic seizures after an average of 4.6 years of recording. About one third of the subjects implanted with bilateral MTL electrodes required >1 month of chronic ambulatory ECoG before the first contralateral MTL electrographic seizure was recorded. Some patients with suspected bilateral MTL seizures had only unilateral electrographic seizures. Chronic ambulatory ECoG in patients with suspected

  2. High spatial resolution spectroscopy of single semiconductor nanostructures

    Science.gov (United States)

    Harris, T. D.; Gershoni, D.; Pfeiffer, L.; Nirmal, M.; Trautman, J. K.; Macklin, J. J.

    1996-11-01

    Low-temperature near-field scanning optical microscopy is used for the first time in spectroscopic studies of single, nanometre dimension, cleaved edge overgrown quantum wires. A direct experimental comparison between a two-dimensional system and a single genuinely one-dimensional quantum wire system, inaccessible to conventional far-field optical spectroscopy, is enabled by the enhanced spatial resolution. We show that the photoluminescence of a single quantum wire is easily distinguished from that of the surrounding quantum well. Emission from localized centres is shown to dominate the photoluminescence from both wires and wells at low temperatures. A factor of three oscillator strength enhancement for these wires compared with the wells is concluded from the photoluminescence excitation data. We also report room-temperature spectroscopy and dynamics of single CdSe nanocrystals. Photochemistry, trap dynamics and spectroscopy are easily determined.

  3. Necessary Contributions of Human Frontal Lobe Subregions to Reward Learning in a Dynamic, Multidimensional Environment.

    Science.gov (United States)

    Vaidya, Avinash R; Fellows, Lesley K

    2016-09-21

    Real-world decisions are typically made between options that vary along multiple dimensions, requiring prioritization of the important dimensions to support optimal choice. Learning in this setting depends on attributing decision outcomes to the dimensions with predictive relevance rather than to dimensions that are irrelevant and nonpredictive. This attribution problem is computationally challenging, and likely requires an interplay between selective attention and reward learning. Both these processes have been separately linked to the prefrontal cortex, but little is known about how they combine to support learning the reward value of multidimensional stimuli. Here, we examined the necessary contributions of frontal lobe subregions in attributing feedback to relevant and irrelevant dimensions on a trial-by-trial basis in humans. Patients with focal frontal lobe damage completed a demanding reward learning task where options varied on three dimensions, only one of which predicted reward. Participants with left lateral frontal lobe damage attributed rewards to irrelevant dimensions, rather than the relevant dimension. Damage to the ventromedial frontal lobe also impaired learning about the relevant dimension, but did not increase reward attribution to irrelevant dimensions. The results argue for distinct roles for these two regions in learning the value of multidimensional decision options under dynamic conditions, with the lateral frontal lobe required for selecting the relevant dimension to associate with reward, and the ventromedial frontal lobe required to learn the reward association itself. The real world is complex and multidimensional; how do we attribute rewards to predictive features when surrounded by competing cues? Here, we tested the critical involvement of human frontal lobe subregions in a probabilistic, multidimensional learning environment, asking whether focal lesions affected trial-by-trial attribution of feedback to relevant and irrelevant

  4. The Optic Lobes Regulate Circadian Rhythms of Olfactory Learning and Memory in the Cockroach.

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    Lubinski, Alexander J; Page, Terry L

    2016-04-01

    The cockroach, Leucophaea maderae, can be trained in an associative olfactory memory task by either classical or operant conditioning. When trained by classical conditioning, memory formation is regulated by a circadian clock, but once the memory is formed, it can be recalled at any circadian time. In contrast, when trained via operant conditioning, animals can learn the task at any circadian phase, but the ability to recall the long-term memory is tied to the phase of training. The optic lobes of the cockroach contain a circadian clock that drives circadian rhythms of locomotor activity, mating behavior, sensitivity of the compound eye to light, and the sensitivity of olfactory receptors in the antennae. To evaluate the role of the optic lobes in regulating learning and memory processes, the authors examined the effects of surgical ablation of the optic lobes on memory formation in classical conditioning and memory recall following operant conditioning. The effect of optic lobe ablation was to "rescue" the deficit in memory acquisition at a time the animals normally cannot learn and "rescue" the animal's ability to recall a memory formed by operant conditioning at a phase where memory was not normally expressed. The results suggested that the optic lobe pacemaker regulates these processes through inhibition at "inappropriate" times of day. As a pharmacological test of this hypothesis, the authors showed that injections of fipronil, an antagonist of GABA and glutamate-activated chloride channels, had the same effects as optic lobe ablation on memory formation and recall. The data suggest that the optic lobes contain the circadian clock(s) that regulate learning and memory processes via inhibition of neural processes in the brain. © 2015 The Author(s).

  5. Effect of needle gauge and lobe laterality on parenchymal liver biopsy outcome: a retrospective analysis.

    Science.gov (United States)

    Vijayaraghavan, Gopal R; Vedantham, Srinivasan; Rangan, Vikram; Karam, Adib; Zheng, Larry; Roychowdhury, Abhijit; Hussain, Sarwat

    2015-06-01

    To analyze the effect of lobe selection, needle gauge, and number of passes on procedure outcomes in terms of specimen length and post-procedure complications. In this HIPAA-compliant, IRB-approved retrospective study, the data from 771 ultrasound-guided adult parenchymal liver biopsies were analyzed. Post-procedure complications were assigned a 3-point rating scale. Associations between specimen length and post-procedure complications with lobe laterality, needle gauge, and number of passes were analyzed. Multivariate logistic regression models were used to analyze the likelihood for achieving a specimen length of at least 2 cm. Post-procedure complications were not associated with lobe laterality, needle gauge, and number of passes (p > 0.3). Specimen length was associated with the number of passes dichotomized at the study mean (p = 0.007), but not with lobe laterality or needle gauge (p > 0.2). After adjusting for lobe laterality and needle gauge, procedures with 1 or 2 passes were associated with a higher likelihood of obtaining a 2 cm or longer specimen (OR 2.469; CI 1.08-5.63, p = 0.0315) than procedures with 3 or more passes, possibly due to poorer sample quality. After adjusting for lobe laterality, an 18-gauge needle was associated with higher odds of a biopsy procedure with 1 or 2 passes (OR 3.665; CI 1.93-6.95, p gauge needle. Lobe laterality was not associated with specimen length or post-procedure complications. An 18-gauge needle compared to a 20-gauge needle could reduce the need for a procedure with more than 2 passes. There was no difference in post-procedure complications between the two needle sizes.

  6. Particle doses in the pulmonary lobes of electronic and conventional cigarette users

    International Nuclear Information System (INIS)

    Manigrasso, Maurizio; Buonanno, Giorgio; Stabile, Luca; Morawska, Lidia; Avino, Pasquale

    2015-01-01

    The main aim of the present study was to estimate size segregated doses from e-cigarette aerosols as a function of the airway generation number in lung lobes. After a 2-second puff, 7.7 × 10 10 particles (D Tot ) with a surface area of 3.6 × 10 3  mm 2 (S Tot ), and 3.3 × 10 10 particles with a surface area of 4.2 × 10 3  mm 2 were deposited in the respiratory system for the electronic and conventional cigarettes, respectively. Alveolar and tracheobronchial deposited doses were compared to the ones received by non-smoking individuals in Western countries, showing a similar order of magnitude. Total regional doses (D R ), in head and lobar tracheobronchial and alveolar regions, ranged from 2.7 × 10 9 to 1.3 × 10 10 particles and 1.1 × 10 9 to 5.3 × 10 10 particles, for the electronic and conventional cigarettes, respectively. D R in the right-upper lung lobe was about twice that found in left-upper lobe and 20% greater in right-lower lobe than the left-lower lobe. - Highlights: • Lobar doses were compared for mainstreams of electronic and conventional cigarettes. • Aerosol doses from e-cigarettes were more than double that from conventional ones. • Doses from a 2-s puff exceed the daily doses of a no smoking Australian subject. • Highest deposition densities occurred at the lobar bronchi. • Aerosol deposition was greater in the right than in the left lung lobes. - Lobar bronchi and right lung lobes represent sites where effects of the aerosol from e-cigarette smoke may be more likely to occur

  7. The gyri of the octopus vertical lobe have distinct neurochemical identities.

    Science.gov (United States)

    Shigeno, Shuichi; Ragsdale, Clifton W

    2015-06-15

    The cephalopod vertical lobe is the largest learning and memory structure known in invertebrate nervous systems. It is part of the visual learning circuit of the central brain, which also includes the superior frontal and subvertical lobes. Despite the well-established functional importance of this system, little is known about neuropil organization of these structures and there is to date no evidence that the five longitudinal gyri of the vertical lobe, perhaps the most distinctive morphological feature of the octopus brain, differ in their connections or molecular identities. We studied the histochemical organization of these structures in hatchling and adult Octopus bimaculoides brains with immunostaining for serotonin, octopus gonadotropin-releasing hormone (oGNRH), and octopressin-neurophysin (OP-NP). Our major finding is that the five lobules forming the vertical lobe gyri have distinct neurochemical signatures. This is most prominent in the hatchling brain, where the median and mediolateral lobules are enriched in OP-NP fibers, the lateral lobule is marked by oGNRH innervation, and serotonin immunostaining heavily labels the median and lateral lobules. A major source of input to the vertical lobe is the superior frontal lobe, which is dominated by a neuropil of interweaving fiber bundles. We have found that this neuropil also has an intrinsic neurochemical organization: it is partitioned into territories alternately enriched or impoverished in oGNRH-containing fascicles. Our findings establish that the constituent lobes of the octopus superior frontal-vertical system have an intricate internal anatomy, one likely to reflect the presence of functional subsystems within cephalopod learning circuitry. © 2015 Wiley Periodicals, Inc.

  8. Fatal stroke after completion pneumonectomy for torsion of left upper lobe following left lower lobectomy

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    Apostolakis Efstratios

    2006-09-01

    Full Text Available Abstract Background The lobar torsion after lung surgery is a rare complication with an incidence of 0.09 to 0.4 %. It may occur after twisting of the bronchovascular pedicle of the remaining lobe after lobectomy, usually on the right side. The 180-degree rotation of the pedicle produces an acute obstruction of the lobar bronchus (atelectasis and of the lobar vessels as well. Without prompt treatment it progresses to lobar ischemia, pulmonary infarction and finally fatal gangrene. Case Presentation A 62 years old female patient was admitted for surgical treatment of lung cancer. She underwent elective left lower lobectomy for squamous cell carcinoma (pT2 N0. The operation was unremarkable, and the patient was extubated in the operating room. After eight hours the patient established decrease of pO2 and chest x-ray showed atelectasis of the lower lobe. To establish diagnosis, bronchoscopy was performed, demonstrating obstructed left lobar bronchus. The patient was re-intubated, and admitted to the operating room where reopening of the thoracotomy was performed. Lobar torsion was diagnosed, with the diaphragmatic surface of the upper lobe facing in an anterosuperior orientation. A completion pneumonectomy was performed. At the end of the procedure the patient developed a right pupil dilatation, presumably due to a cerebral embolism. A subsequent brain angio-CT scan established the diagnosis. She died at the intensive care unit 26 days later. Conclusion The thoracic surgeon should suspect this rare early postoperative complication after any thoracic operation in every patient with atelectasis of the neighboring lobe. High index of suspicion and prompt diagnosis may prevent catastrophic consequences, such as, infarction or gangrene of the pulmonary lobe. During thoracic operations, especially whenever the lung or lobe hilum is full mobilized, fixation of the remaining lobe may prevent this life threatening complication.

  9. Mapping QTL Contributing to Variation in Posterior Lobe Morphology between Strains of Drosophila melanogaster.

    Directory of Open Access Journals (Sweden)

    Jennifer L Hackett

    Full Text Available Closely-related, and otherwise morphologically similar insect species frequently show striking divergence in the shape and/or size of male genital structures, a phenomenon thought to be driven by sexual selection. Comparative interspecific studies can help elucidate the evolutionary forces acting on genital structures to drive this rapid differentiation. However, genetic dissection of sexual trait divergence between species is frequently hampered by the difficulty generating interspecific recombinants. Intraspecific variation can be leveraged to investigate the genetics of rapidly-evolving sexual traits, and here we carry out a genetic analysis of variation in the posterior lobe within D. melanogaster. The lobe is a male-specific process emerging from the genital arch of D. melanogaster and three closely-related species, is essential for copulation, and shows radical divergence in form across species. There is also abundant variation within species in the shape and size of the lobe, and while this variation is considerably more subtle than that seen among species, it nonetheless provides the raw material for QTL mapping. We created an advanced intercross population from a pair of phenotypically-different inbred strains, and after phenotyping and genotyping-by-sequencing the recombinants, mapped several QTL contributing to various measures of lobe morphology. The additional generations of crossing over in our mapping population led to QTL intervals that are smaller than is typical for an F2 mapping design. The intervals we map overlap with a pair of lobe QTL we previously identified in an independent mapping cross, potentially suggesting a level of shared genetic control of trait variation. Our QTL additionally implicate a suite of genes that have been shown to contribute to the development of the posterior lobe. These loci are strong candidates to harbor naturally-segregating sites contributing to phenotypic variation within D. melanogaster, and

  10. Altered anterior-posterior connectivity through the arcuate fasciculus in temporal lobe epilepsy.

    Science.gov (United States)

    Takaya, Shigetoshi; Liu, Hesheng; Greve, Douglas N; Tanaka, Naoaki; Leveroni, Catherine; Cole, Andrew J; Stufflebeam, Steven M

    2016-12-01

    How the interactions between cortices through a specific white matter pathway change during cognitive processing in patients with epilepsy remains unclear. Here, we used surface-based structural connectivity analysis to examine the change in structural connectivity with Broca's area/the right Broca's homologue in the lateral temporal and inferior parietal cortices through the arcuate fasciculus (AF) in 17 patients with left temporal lobe epilepsy (TLE) compared with 17 healthy controls. Then, we investigated its functional relevance to the changes in task-related responses and task-modulated functional connectivity with Broca's area/the right Broca's homologue during a semantic classification task of a single word. The structural connectivity through the AF pathway and task-modulated functional connectivity with Broca's area decreased in the left midtemporal cortex. Furthermore, task-related response decreased in the left mid temporal cortex that overlapped with the region showing a decrease in the structural connectivity. In contrast, the region showing an increase in the structural connectivity through the AF overlapped with the regions showing an increase in task-modulated functional connectivity in the left inferior parietal cortex. These structural and functional changes in the overlapping regions were correlated. The results suggest that the change in the structural connectivity through the left frontal-temporal AF pathway underlies the altered functional networks between the frontal and temporal cortices during the language-related processing in patients with left TLE. The left frontal-parietal AF pathway might be employed to connect anterior and posterior brain regions during language processing and compensate for the compromised left frontal-temporal AF pathway. Hum Brain Mapp 37:4425-4438, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  11. Evidence for brainstem network disruption in temporal lobe epilepsy and sudden unexplained death in epilepsy

    Directory of Open Access Journals (Sweden)

    Susanne G. Mueller

    2014-01-01

    Full Text Available The symptoms witnessed in unexplained death in epilepsy (SUDEP suggest a breakdown of central autonomic control. Since the brainstem plays a crucial role in autonomic control, the objectives of this study were 1. To investigate if temporal lobe epilepsy (TLE is associated with brainstem atrophy and to characterize it using graph Analysis 2. To compare the findings with those in two probable TLESUDEP. T1 images were obtained from 17 controls, 30 TLE (16 with mesial-temporal-sclerosis (TLE-MTS and 14 without (TLE-no and from 2 patients who died of SUDEP. The brainstem was extracted, warped onto a brainstem atlas and Jacobian determinants maps (JDM calculated. SPM8 was used to compare the JDMs at the group level, z-score maps were calculated for single subject analysis. Brainstem regions encompassing autonomic structures were identified based on macroscopic landmarks and mean z-scores from 5 × 5 × 5 voxel cubes extracted to calculate a new measure called atrophy-similarity index (ASI for graph analysis. TLE-MTS had volume loss in the dorsal mesencephalon. The SUDEP cases had severe and more extensive volume loss in the same region. Nodal degrees and participation coefficients were decreased and local efficiency increased in SUDEP compared to controls. TLE is associated with volume loss in brainstem regions involved in autonomic control. Structural damage in these regions might increase the risk for a fatal dysregulation during situations with increased demand such as following severe seizures.

  12. Cognitive outcome two years after frontal lobe resection for epilepsy--a prospective longitudinal study.

    Science.gov (United States)

    Ljunggren, Sofia; Andersson-Roswall, Lena; Rydenhag, Bertil; Samuelsson, Hans; Malmgren, Kristina

    2015-08-01

    To investigate cognitive outcomes after frontal lobe resection (FLR) for epilepsy in a consecutive single centre series. Neuropsychological examinations were performed prior to and two years (mean test interval 2.5 years) after surgery in 30 consecutive patients who underwent FLR. Cognitive outcome was evaluated with particular consideration to the site of surgery (lateral, premotor/SMA [supplementary motor area], mesial/orbital). Cognitive domains assessed were speed, language, memory, attention, executive functions and intelligence. 25 healthy controls were assessed at corresponding time points (mean test interval 3.0 years). Analyses were made both at group and individual levels. At baseline the patients performed below controls in variables depending on speed, executive functions, global and verbal intelligence. Two years after surgery, the analyses at the subgroup level indicated that the lateral resection group had less improvement than the controls in global intelligence, FSIQ (p=.037). However, at the individual level, the majority of the change scores (74-100%) were classified as within the normal range for all but one variable. The exception was the variable "Comprehension" (measuring verbal reasoning ability) with reliable declines in 44% (8/18) of the patients. This pattern of decline was observed in the lateral (4/7 patients) and premotor/SMA (4/7 patients) resection groups. Seizure outcome and side of surgery did not influence these results. The main finding was cognitive stability at group level two years after FLR. A reliable decline in verbal reasoning ability was rather common at an individual level, but only in the lateral and premotor/SMA resection groups. The lateral resection group also had less improvement than the controls in global intelligence. Copyright © 2015 British Epilepsy Association. Published by Elsevier Ltd. All rights reserved.

  13. Dose–Volume Relationships Associated With Temporal Lobe Radiation Necrosis After Skull Base Proton Beam Therapy

    Energy Technology Data Exchange (ETDEWEB)

    McDonald, Mark W., E-mail: markmcdonaldmd@gmail.com [Department of Radiation Oncology, Indiana University School of Medicine, Indianapolis, Indiana (United States); Indiana University Health Proton Therapy Center, Bloomington, Indiana (United States); Linton, Okechukwu R. [Department of Radiation Oncology, Indiana University School of Medicine, Indianapolis, Indiana (United States); Calley, Cynthia S.J. [Department of Biostatistics, Indiana University School of Medicine, Indianapolis, Indiana (United States)

    2015-02-01

    Purpose: We evaluated patient and treatment parameters correlated with development of temporal lobe radiation necrosis. Methods and Materials: This was a retrospective analysis of a cohort of 66 patients treated for skull base chordoma, chondrosarcoma, adenoid cystic carcinoma, or sinonasal malignancies between 2005 and 2012, who had at least 6 months of clinical and radiographic follow-up. The median radiation dose was 75.6 Gy (relative biological effectiveness [RBE]). Analyzed factors included gender, age, hypertension, diabetes, smoking status, use of chemotherapy, and the absolute dose:volume data for both the right and left temporal lobes, considered separately. A generalized estimating equation (GEE) regression analysis evaluated potential predictors of radiation necrosis, and the median effective concentration (EC50) model estimated dose–volume parameters associated with radiation necrosis. Results: Median follow-up time was 31 months (range 6-96 months) and was 34 months in patients who were alive. The Kaplan-Meier estimate of overall survival at 3 years was 84.9%. The 3-year estimate of any grade temporal lobe radiation necrosis was 12.4%, and for grade 2 or higher radiation necrosis was 5.7%. On multivariate GEE, only dose–volume relationships were associated with the risk of radiation necrosis. In the EC50 model, all dose levels from 10 to 70 Gy (RBE) were highly correlated with radiation necrosis, with a 15% 3-year risk of any-grade temporal lobe radiation necrosis when the absolute volume of a temporal lobe receiving 60 Gy (RBE) (aV60) exceeded 5.5 cm{sup 3}, or aV70 > 1.7 cm{sup 3}. Conclusions: Dose–volume parameters are highly correlated with the risk of developing temporal lobe radiation necrosis. In this study the risk of radiation necrosis increased sharply when the temporal lobe aV60 exceeded 5.5 cm{sup 3} or aV70 > 1.7 cm{sup 3}. Treatment planning goals should include constraints on the volume of temporal lobes receiving

  14. Clinical observations on attention-deficit hyperactivity disorder (ADHD) in children with frontal lobe epilepsy.

    Science.gov (United States)

    Zhang, Dong-Qing; Li, Fu-Hai; Zhu, Xiao-Bo; Sun, Ruo-Peng

    2014-01-01

    The objective was to investigate the prevalence of attention-deficit hyperactivity disorder (ADHD) in children with frontal lobe epilepsy and related factors. The medical records of 190 children diagnosed with frontal lobe epilepsy at Qilu Hospital of Shandong University between 2006 and 2011 were retrospectively collected, and a follow-up analysis of the prevalence of ADHD in these children was conducted. Of the 161 children with an effective follow-up, 59.0% (95/161) with frontal lobe epilepsy suffered from ADHD as well. Analysis of epilepsy and ADHD-related factors indicated that the incidence of ADHD was 89.4% (76/85) in children with abnormal electroencephalogram (EEG) discharges on the most recent EEG, which was significantly higher than the ADHD incidence of 25% (19/76) in children with normal readings on the most recent EEG (P frontal lobe epilepsy have a high incidence of ADHD. Sustained abnormal discharge on the electroencephalogram is associated with increased comorbidity of ADHD with frontal lobe epilepsy.

  15. Female verbal memory advantage in temporal, but not frontal lobe epilepsy.

    Science.gov (United States)

    Berger, Justus; Demin, Katharina; Holtkamp, Martin; Bengner, Thomas

    2018-01-01

    Women show better performance than men on a range of episodic memory tasks. Evidence regarding a neuroanatomical localization of this effect remains ambiguous. It has been suggested that anterior temporal lobe structures are responsible for sex differences in verbal memory, yet temporal lobe epilepsy (TLE) and TLE surgery do not affect women's verbal memory advantage. Instead, frontal lobe regions may be relevant for female verbal memory superiority, i.e. by enabling more efficient encoding and retrieval strategies in women. The aim of the present study was to investigate whether women's verbal memory advantage can be found in patients with frontal lobe epilepsy (FLE), and how patients with FLE and those with TLE differ with regard to sex differences in verbal memory. Fifty patients with unilateral FLE (26 women, 24 men) were compared with 183 patients with unilateral TLE (90 women, 93 men) on both verbal learning and delayed memory. We found that women showed better verbal memory than men in the TLE group, but not in the FLE group. In addition, we found that patients with TLE showed worse verbal learning than those with FLE. Our findings support the idea that women's advantage in verbal memory may be related to frontal lobe function. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. Frontal Lobe Contusion in Mice Chronically Impairs Prefrontal-Dependent Behavior.

    Science.gov (United States)

    Chou, Austin; Morganti, Josh M; Rosi, Susanna

    2016-01-01

    Traumatic brain injury (TBI) is a major cause of chronic disability in the world. Moderate to severe TBI often results in damage to the frontal lobe region and leads to cognitive, emotional, and social behavioral sequelae that negatively affect quality of life. More specifically, TBI patients often develop persistent deficits in social behavior, anxiety, and executive functions such as attention, mental flexibility, and task switching. These deficits are intrinsically associated with prefrontal cortex (PFC) functionality. Currently, there is a lack of analogous, behaviorally characterized TBI models for investigating frontal lobe injuries despite the prevalence of focal contusions to the frontal lobe in TBI patients. We used the controlled cortical impact (CCI) model in mice to generate a frontal lobe contusion and studied behavioral changes associated with PFC function. We found that unilateral frontal lobe contusion in mice produced long-term impairments to social recognition and reversal learning while having only a minor effect on anxiety and completely sparing rule shifting and hippocampal-dependent behavior.

  17. Scannographic appearance of increased colloid uptake in the left liver lobe (Case presentation)

    International Nuclear Information System (INIS)

    Tadzher, Isak S.; Josifovska, Tatjana; Popgjorcheva, Daniela

    1996-01-01

    Incidentally increased uptake of Tc-99m sulfur colloid was found in scannographic images in the whole left liver lobe in all positions (PA, AP, DL, LL). The patient, a 60-year-old woman, was three years earlier cholocystecomized and had since occasional pain in the right upper abdominal quadrant due to biliary dyskinesia. Accessory spleen tissue was seen as well in the inferior lineal pole, probably presenting Shurer's phenomenon of 'lienis in liene' thus augmenting the serendipity of the scanographic findings. Imaging of the accessory spleen with heat denaturated spherocytes - Tc-99m confirmed the lienal structure of the tissue with preserved red pulp trabecular trapping mechanism in addition to phagocytic function of lineal Kupffer cells (in white pulp). Mebrofenin-Tc-99m (IDA-agent) showed in our patient normal distribution in both liver lobes contrary to focal nodular hyperplasia and adenoma of the liver where IDA-radio- pharmaceuticals have delayed clearance due to abnormal biliary canaliculi. In our patient uptake, distribution, excretion and liver washout of mebrofenin-Tc-99m was found to be normal. This is in favor of an exclusive, solitary increase of the number of Kupffer cells confined to the whole left lobe of the liver. Increased colloid uptake in the left liver lobe is dependent on a greater number of Kupffer cells pro volume than in the right lobe. (Author)

  18. Lobe-cleft instability in the buoyant gravity current generated by estuarine outflow

    Science.gov (United States)

    Horner-Devine, Alexander R.; Chickadel, C. Chris

    2017-05-01

    Gravity currents represent a broad class of geophysical flows including turbidity currents, powder avalanches, pyroclastic flows, sea breeze fronts, haboobs, and river plumes. A defining feature in many gravity currents is the formation of three-dimensional lobes and clefts along the front and researchers have sought to understand these ubiquitous geophysical structures for decades. The prevailing explanation is based largely on early laboratory and numerical model experiments at much smaller scales, which concluded that lobes and clefts are generated due to hydrostatic instability exclusively in currents propagating over a nonslip boundary. Recent studies suggest that frontal dynamics change as the flow scale increases, but no measurements have been made that sufficiently resolve the flow structure in full-scale geophysical flows. Here we use thermal infrared and acoustic imaging of a river plume to reveal the three-dimensional structure of lobes and clefts formed in a geophysical gravity current front. The observed lobes and clefts are generated at the front in the absence of a nonslip boundary, contradicting the prevailing explanation. The observed flow structure is consistent with an alternative formation mechanism, which predicts that the lobe scale is inherited from subsurface vortex structures.

  19. MRI and brain spect findings in patients with unilateral temporal lobe epilepsy and normal CT scan

    Directory of Open Access Journals (Sweden)

    P.G. Carrilho

    1994-06-01

    Full Text Available 26 patients with temporal lobe epilepsy clinically documented by several abnormal interictal surface EEGs with typical unitemporal epileptiform activity and a normal CT scan were studied. Interictal99mTC HMPAO brain SPECT and MRI were performed in all subjects. Abnormalities were shown in 61.5% of MRI (n=16 and 65.4% of SPECT (n=17. Hippocampal atrophy associated to a high signal on T2-weighted MRI slices suggesting mesial temporal sclerosis was the main finding (n=12; 75% of abnormal MRI. MRI correlated well to surface EEG in 50% (n=13. There was also a good correlation between MRI and SPECT in 30.7% (n=8. SPECT and EEG were in agreement in 57.7% (n=l5. MRI, SPECT and EEG were congruent in 26.9% (n=7. These results support the usefulness of interictal brain SPECT and MRI in detecting lateralized abnormalities in temporal lobe epilepsy. On the other hand, in two cases, interictal SPECT correlated poorly with surface EEG. This functional method should not be used isolately in the detection of temporal lobe foci. MRI is more useful than CT as a neuroimaging technique in temporal lobe epilepsy. It may detect small structural lesions and mesial temporal lobe sclerosis which are not easily seen with traditional CT scanning.

  20. Image processing analysis of vortex dynamics of lobed jets from three-dimensional diffusers

    Energy Technology Data Exchange (ETDEWEB)

    Nastase, Ilinca [Technical University of Civil Engineering in Bucharest, Building Services Department, 66 Avenue Pache Protopopescu, 020396, Bucharest (Romania); Meslem, Amina; El Hassan, Mouhammad, E-mail: inastase@instal.utcb.ro, E-mail: ameslem@univ-lr.fr [LEPTIAB, University of La Rochelle, Pole Sciences et Technologie, avenue Michel Crepeau, 17042 La Rochelle (France)

    2011-12-01

    The passive control of jet flows with the aim to enhance mixing and entrainment is of wide practical interest. Our purpose here is to develop new air diffusers for heating ventilating air conditioning systems by using lobed geometry nozzles, in order to ameliorate the users' thermal comfort. Two turbulent six-lobed air jets, issued from a lobed tubular nozzle and an innovative hemispherical lobed nozzle, were studied experimentally. It was shown that the proposed innovative concept of a lobed jet, which can be easily integrated in air diffusion devices, is very efficient regarding induction capability. A vortical dynamics analysis for the two jets is performed using a new method of image processing, namely dynamic mode decomposition. A validation of this method is also proposed suggesting that the dynamical mode decomposition (DMD) image processing method succeeds in capturing the most dominant frequencies of the flow dynamics, which in our case are related to the quite special dynamics of the Kelvin-Helmholtz vortices.

  1. Current Topics Regarding the Function of the Medial Temporal Lobe Memory System.

    Science.gov (United States)

    Clark, Robert E

    2018-01-05

    The first clear insight that the medial temporal lobe of the human brain was in fact a system of anatomically connected structures that were organized into a memory system came in 1957 from the observations by Brenda Milner of the noted amnesic patient H.M. Subsequent work in humans, monkeys, and rodents has identified all of the components of the medial temporal lobe (MTL) that formed the memory system. Currently, work is ongoing to identify the specific contributions each structure in the medial temporal lobe makes towards the formation and storage of long-term declarative memory. The historical background of this work is described including what insights the study of noted neurologic patients H.M. and E.P. provided for understanding the function of the medial temporal lobe. The development of an animal model of medial temporal lobe function is described. Additionally, the insights that lead to the understanding that the brain contains multiple, anatomically discrete, memory systems are described. Finally, three current topics of debate are addressed: First, does the perirhinal cortex exclusively support memory, or does it support both memory and higher order visual perception? Second, is there an anatomical separation between recollection and familiarity ? Third, is the organization of spatial memory different between humans and rats, or perhaps the difference is between the working memory capacities of the two species?

  2. Morphology and morphometry of the caudate lobe of the liver in two populations.

    Science.gov (United States)

    Sagoo, Mandeep Gill; Aland, R Claire; Gosden, Edward

    2018-01-01

    The caudate lobe of the liver has portal blood supply and hepatic vein drainage independent of the remainder of the liver and may be differentially affected in liver pathologies. Ultrasonographic measurement of the caudate lobe can be used to generate hepatic indices that may indicate cirrhosis. This study investigated the relationship of metrics of the caudate lobe and other morphological features of human livers from a northwest Indian Punjabi population (n = 50) and a UK Caucasian population (n = 25), which may affect the calculation of hepatic indices. The width of the right lobe of the liver was significantly smaller, while the anteroposterior diameter of the caudate lobe and both Harbin's Index and the Hess Index scores were significantly larger in NWI livers than in UKC livers. The Hess Index score, in particular, is much larger in the NWI population (265 %, p morphological features of the liver. These differences may affect the calculation of hepatic indices, resulting in a greater percentage of false positives of cirrhosis in the NWI population. Population-specific data are required to correctly determine normal ranges.

  3. Automatic lung lobe segmentation of COPD patients using iterative B-spline fitting

    Science.gov (United States)

    Shamonin, D. P.; Staring, M.; Bakker, M. E.; Xiao, C.; Stolk, J.; Reiber, J. H. C.; Stoel, B. C.

    2012-02-01

    We present an automatic lung lobe segmentation algorithm for COPD patients. The method enhances fissures, removes unlikely fissure candidates, after which a B-spline is fitted iteratively through the remaining candidate objects. The iterative fitting approach circumvents the need to classify each object as being part of the fissure or being noise, and allows the fissure to be detected in multiple disconnected parts. This property is beneficial for good performance in patient data, containing incomplete and disease-affected fissures. The proposed algorithm is tested on 22 COPD patients, resulting in accurate lobe-based densitometry, and a median overlap of the fissure (defined 3 voxels wide) with an expert ground truth of 0.65, 0.54 and 0.44 for the three main fissures. This compares to complete lobe overlaps of 0.99, 0.98, 0.98, 0.97 and 0.87 for the five main lobes, showing promise for lobe segmentation on data of patients with moderate to severe COPD.

  4. Particle doses in the pulmonary lobes of electronic and conventional cigarette users.

    Science.gov (United States)

    Manigrasso, Maurizio; Buonanno, Giorgio; Stabile, Luca; Morawska, Lidia; Avino, Pasquale

    2015-07-01

    The main aim of the present study was to estimate size segregated doses from e-cigarette aerosols as a function of the airway generation number in lung lobes. After a 2-second puff, 7.7 × 10(10) particles (DTot) with a surface area of 3.6 × 10(3) mm(2) (STot), and 3.3 × 10(10) particles with a surface area of 4.2 × 10(3) mm(2) were deposited in the respiratory system for the electronic and conventional cigarettes, respectively. Alveolar and tracheobronchial deposited doses were compared to the ones received by non-smoking individuals in Western countries, showing a similar order of magnitude. Total regional doses (D(R)), in head and lobar tracheobronchial and alveolar regions, ranged from 2.7 × 10(9) to 1.3 × 10(10) particles and 1.1 × 10(9) to 5.3 × 10(10) particles, for the electronic and conventional cigarettes, respectively. D(R) in the right-upper lung lobe was about twice that found in left-upper lobe and 20% greater in right-lower lobe than the left-lower lobe. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. Fast computation of far-field pulse-echo PSF of arbitrary arrays for large sparse 2-D ultrasound array design.

    Science.gov (United States)

    Li, Zhaohui; Chi, Cheng

    2018-03-01

    Large wideband two-dimensional (2-D) arrays are essential for high-resolution three-dimensional (3-D) ultrasound imaging. Since the tremendous element number of a full sampled large 2-D array is not affordable in any practical 3-D ultrasound imaging system, it is necessary to reduce the element number through sparse 2-D array design. Sparse array design requires that both the positions and weights of the array elements should be arbitrarily alterable. Hence a proper evaluation tool that can deal with arbitrary array is integral to optimizing the array structure and apodization function. It is known that pulse-echo point spread function (PSF) has been a common tool used to evaluate the performance of wideband arrays in ultrasound imaging all along, which also plays an important role in wideband ultrasound simulations. However, so far the conventional ultrasound simulation tools can only calculate pulse-echo PSF of arbitrary wideband arrays in the time domain because of the existence of nonuniform nodes in the spatial impulse response expressions, which obstructs their application of FFT to do fast computation of the time-domain convolutions. As a result, ultra-high time consumption of pulse-echo PSF computation of a large arbitrary wideband array hampers it to be taken as the evaluation tool by any stochastic optimization methods which need massive iterations in designing large sparse 2-D arrays. This paper aims to make available the pulse-echo PSF tool in designing large sparse 2-D arrays by proposing a fast computation method of far-field pulse-echo PSFs of arbitrary wideband arrays. In the paper, fast computation of wideband spatial impulse responses of a 2-D array is first realized in frequency domain by employing the nonuniform fast Fourier transform (NUFFT), under the point source assumption in far-field. On the basis of that, fast computation of time-domain convolutions is made possible by using FFT. In addition, a short inverse FFT (IFFT) is applied in

  6. Effects of near surface soil moisture profiles during evaporation on far-field ground-penetrating radar data: A numerical study

    KAUST Repository

    Moghadas, Davood

    2013-01-01

    We theoretically investigated the effect of vapor flow on the drying front that develops in soils when water evaporates from the soil surface and on GPR data. The results suggest the integration of the full-wave GPR model with a coupled water, vapor, and heat flow model to accurately estimate the soil hydraulic properties. We investigated the Effects of a drying front that emerges below an evaporating soil surface on the far-field ground-penetrating radar (GPR) data. First, we performed an analysis of the width of the drying front in soils with 12 different textures by using an analytical model. Then, we numerically simulated vertical soil moisture profiles that develop during evaporation for the soil textures. We performed the simulations using a Richards flow model that considers only liquid water flow and a model that considers coupled water, vapor, and heat flows. The GPR signals were then generated from the simulated soil water content profiles taking into account the frequency dependency of apparent electrical conductivity and dielectric permittivity. The analytical approach indicated that the width of the drying front at the end of Stage I of the evaporation was larger in silty soils than in other soil textures and smaller in sandy soils. We also demonstrated that the analytical estimate of the width of the drying front can be considered as a proxy for the impact that a drying front could have on far-field GPR data. The numerical simulations led to the conclusion that vapor transport in soil resulted in S-shaped soil moisture profiles, which clearly influenced the GPR data. As a result, vapor flow needs to be considered when GPR data are interpreted in a coupled inversion approach. Moreover, the impact of vapor flow on the GPR data was larger for silty than for sandy soils. These Effects on the GPR data provide promising perspectives regarding the use of radars for evaporation monitoring. © Soil Science Society of America 5585 Guilford Rd., Madison, WI

  7. Far-field tsunami of 2017 Mw 8.1 Tehuantepec, Mexico earthquake recorded by Chilean tide gauge network: Implications for tsunami warning systems

    Science.gov (United States)

    González-Carrasco, J. F.; Benavente, R. F.; Zelaya, C.; Núñez, C.; Gonzalez, G.

    2017-12-01

    The 2017 Mw 8.1, Tehuantepec earthquake generated a moderated tsunami, which was registered in near-field tide gauges network activating a tsunami threat state for Mexico issued by PTWC. In the case of Chile, the forecast of tsunami waves indicate amplitudes less than 0.3 meters above the tide level, advising an informative state of threat, without activation of evacuation procedures. Nevertheless, during sea level monitoring of network we detect wave amplitudes (> 0.3 m) indicating a possible change of threat state. Finally, NTWS maintains informative level of threat based on mathematical filtering analysis of sea level records. After 2010 Mw 8.8, Maule earthquake, the Chilean National Tsunami Warning System (NTWS) has increased its observational capabilities to improve early response. Most important operational efforts have focused on strengthening tide gauge network for national area of responsibility. Furthermore, technological initiatives as Integrated Tsunami Prediction and Warning System (SIPAT) has segmented the area of responsibility in blocks to focus early warning and evacuation procedures on most affected coastal areas, while maintaining an informative state for distant areas of near-field earthquake. In the case of far-field events, NTWS follow the recommendations proposed by Pacific Tsunami Warning Center (PTWC), including a comprehensive monitoring of sea level records, such as tide gauges and DART (Deep-Ocean Assessment and Reporting of Tsunami) buoys, to evaluate the state of tsunami threat in the area of responsibility. The main objective of this work is to analyze the first-order physical processes involved in the far-field propagation and coastal impact of tsunami, including implications for decision-making of NTWS. To explore our main question, we construct a finite-fault model of the 2017, Mw 8.1 Tehuantepec earthquake. We employ the rupture model to simulate a transoceanic tsunami modeled by Neowave2D. We generate synthetic time series at

  8. Transverse single-mode edge-emitting lasers based on coupled waveguides.

    Science.gov (United States)

    Gordeev, Nikita Yu; Payusov, Alexey S; Shernyakov, Yuri M; Mintairov, Sergey A; Kalyuzhnyy, Nikolay A; Kulagina, Marina M; Maximov, Mikhail V

    2015-05-01

    We report on the transverse single-mode emission from InGaAs/GaAs quantum well edge-emitting lasers with broadened waveguide. The lasers are based on coupled large optical cavity (CLOC) structures where high-order vertical modes of the broad active waveguide are suppressed due to their resonant tunneling into a coupled single-mode passive waveguide. The CLOC lasers have shown stable Gaussian-shaped vertical far-field profiles with a reduced divergence of ∼22° FWHM (full width at half-maximum) in CW (continuous-wave) operation.

  9. MTA index: a simple 2D-method for assessing atrophy of the medial temporal lobe using clinically available neuroimaging

    Directory of Open Access Journals (Sweden)

    Manuel eMenéndez-González

    2014-03-01

    Full Text Available Background and purpose: Despite a strong correlation between severity of Alzheimer disease (AD pathology and medial temporal lobe atrophy (MTA, its measurement has not been widely used in daily clinical practice as a criterion in the diagnosis of prodromal and probable AD. This is mainly because the methods available to date are sophisticated and difficult to implement for routine use in most hospitals. In this pilot study we aim to describe a novel, simple and objective method for measuring the rate of MTA in relation to the global atrophy using clinically available neuroimaging and describe the rationale behind this method.Description: This method consists of calculating a ratio of 3 regions traced manually on one single coronal MRI slide at the level of the interpeduncular fossa: i the medial temporal lobe region (A; ii the parenchyma within the medial temporal region, that includes the hippocampus and the parahippocampal gyrus -the fimbriae taenia and choroid plexus are excluded- (B; and iii the body of the ipsilateral lateral ventricle (C. Therefore we can compute the ratio Medial Temporal Atrophy index at both sides as follows: MTAi = (A-B x10/C.Conclusions: The MTAi is a simple 2D-method for measuring the relative extent of atrophy in the MTL in relation to the global brain atrophy. This method can be useful for a more accurate diagnosis of AD in routine clinical practice. Further studies are needed to assess the usefulness of MTAi in the diagnosis of early AD, in tracking the progression of AD and in the differential diagnosis of AD with other dementias.

  10. Neural Organization of the Optic Lobe Changes Steadily from Late Embryonic Stage to Adulthood in CuttlefishSepia pharaonis.

    Science.gov (United States)

    Liu, Yung-Chieh; Liu, Tsung-Han; Su, Chia-Hao; Chiao, Chuan-Chin

    2017-01-01

    The optic lobe is the largest structure in the cuttlefish brain. While the general morphology of the optic lobe in adult cuttlefish has been well described, the 3D structure and ontogenetic development of its neural organization have not been characterized. To correlate observed behavioral changes within the brain structure along the development of this animal, optic lobes from the late embryonic stage to adulthood were examined systematically in the present study. The MRI scan revealed that the so called "cell islands" in the medulla of the cephalopod's optic lobe (Young, 1962, 1974) are in fact a contiguous tree-like structure. Quantification of the neural organizational development of optic lobes showed that structural features of the cortex and radial column zone were established earlier than those of the tangential zone during embryonic and post-hatching stages. Within the cell islands, the density of nuclei was decreased while the size of nuclei was increased during the development. Furthermore, the visual processing area in the optic lobe showed a significant variation in lateralization during embryonic and juvenile stages. Our observation of a continuous increase in neural fibers and nucleus size in the tangential zone of the optic lobe from late embryonic stage to adulthood indicates that the neural organization of the optic lobe is modified along the development of cuttlefish. These findings thus support that the ontogenetic change of the optic lobe is responsible for their continuously increased complexity in body patterning and visuomotor behaviors.

  11. Alfvén waves in the near-PSBL lobe: Cluster observations

    Directory of Open Access Journals (Sweden)

    T. Takada

    2006-05-01

    Full Text Available Electromagnetic low-frequency waves in the magnetotail lobe close to the PSBL (Plasma Sheet Boundary Layer are studied using the Cluster spacecraft. The lobe waves show Alfvénic properties and transport their wave energy (Poynting flux on average toward the Earth along magnetic field lines. Most of the wave events are rich with oxygen (O+ ion plasma. The rich O+ plasma can serve to enhance the magnetic field fluctuations, resulting in a greater likelihood of observation, but it does not appear to be necessary for the generation of the waves. Taking into account the fact that all events are associated with auroral electrojet enhancements, the source of the lobe waves might be a substorm-associated instability, i.e. some instability near the reconnection site, or an ion beam-related instability in the PSBL.

  12. Alfvén waves in the near-PSBL lobe: Cluster observations

    Directory of Open Access Journals (Sweden)

    T. Takada

    2006-05-01

    Full Text Available Electromagnetic low-frequency waves in the magnetotail lobe close to the PSBL (Plasma Sheet Boundary Layer are studied using the Cluster spacecraft. The lobe waves show Alfvénic properties and transport their wave energy (Poynting flux on average toward the Earth along magnetic field lines. Most of the wave events are rich with oxygen (O+ ion plasma. The rich O+ plasma can serve to enhance the magnetic field fluctuations, resulting in a greater likelihood of observation, but it does not appear to be necessary for the generation of the waves. Taking into account the fact that all events are associated with auroral electrojet enhancements, the source of the lobe waves might be a substorm-associated instability, i.e. some instability near the reconnection site, or an ion beam-related instability in the PSBL.

  13. Temporal lobe epilepsy: Comparison of CT and MR in 100 patients

    International Nuclear Information System (INIS)

    Schoerner, W.; Meencke, H.J.; Sander, B.; Henkes, H.; Felix, R.; Klinikum Rudolf Virchow, Berlin

    1989-01-01

    The value of CT and MR was studied in 100 patients with temporal lobe epilepsy. Axial CT scans were obtained before and after contrast injection. Coronary MR scans were carried out with T 1 -(SE 400/30, GE 315/14) and T 2 -weighted sequences (SE 1600/30 + 70). A circumscribed lesion was demonstrated in fifteen patients by CT and in 25 patients by MR. With the exception of a small area of calcification, all lesions seen on CT could also be recognized on MR. Better sensitivity and improved demonstration of the temporal lobes makes MR the method of choice in the diagnosis of temporal lobe epilepsy. (orig./GDG) [de

  14. Phenylephrine but not ephedrine reduces frontal lobe oxygenation following anesthesia-induced hypotension

    DEFF Research Database (Denmark)

    Nissen, Peter; Brassard, Patrice; Jørgensen, Thomas

    2010-01-01

    BACKGROUND: Vasopressor agents are used to correct anesthesia-induced hypotension. We describe the effect of phenylephrine and ephedrine on frontal lobe oxygenation (S(c)O(2)) following anesthesia-induced hypotension. METHODS: Following induction of anesthesia by fentanyl (0.15 mg kg(-1......)) and propofol (2.0 mg kg(-1)), 13 patients received phenylephrine (0.1 mg iv) and 12 patients received ephedrine (10 mg iv) to restore mean arterial pressure (MAP). Heart rate (HR), MAP, stroke volume (SV), cardiac output (CO), and frontal lobe oxygenation (S(c)O(2)) were registered. RESULTS: Induction...... induced by anesthesia has a negative impact on S(c)O(2) while ephedrine maintains frontal lobe oxygenation potentially related to an increase in CO....

  15. Prognostic factors for outcome in pediatric probable lesional frontal lobe epilepsy with an unknown cause (cryptogenic).

    Science.gov (United States)

    Lee, Inn-Chi; Chen, Yung-Jung; Lee, Hong-Shen; Li, Shuan-Yow

    2014-12-01

    The outcomes of children with cryptogenic seizures most probably arising from the frontal lobe are difficult to predict. We retrospectively collected data on 865 pediatric patients with epilepsy. In 78 patients with cryptogenic frontal lobe epilepsy, the age at first seizure was inversely correlated with the outcome, including the degree of intellectual disability/developmental delay (P = .002) and seizure frequency (P = .02) after adequate treatment. Intellectual disability was more prevalent in children with a first seizure at 0 to 3 years old (P = .002), and seizures were more frequent in those with a first seizure at 0 to 6 years old than at 7 to 16 years old (P = .026). For pediatric cryptogenic frontal lobe epilepsy, the age at first seizure is important and inversely correlated with outcome, including seizure frequency and intellectual disability. © The Author(s) 2013.

  16. De novo 12q22.q23.3 duplication associated with temporal lobe epilepsy.

    Science.gov (United States)

    Vari, Maria Stella; Traverso, Monica; Bellini, Tommaso; Madia, Francesca; Pinto, Francesca; Minetti, Carlo; Striano, Pasquale; Zara, Federico

    2017-08-01

    Temporal lobe epilepsy (TLE) is the most common form of focal epilepsy and may be associated with acquired central nervous system lesions or could be genetic. Various susceptibility genes and environmental factors are believed to be involved in the aetiology of TLE, which is considered to be a heterogeneous, polygenic, and complex disorder. Rare point mutations in LGI1, DEPDC5, and RELN as well as some copy number variations (CNVs) have been reported in families with TLE patients. We perform a genetic analysis by Array-CGH in a patient with dysmorphic features and temporal lobe epilepsy. We report a de novo duplication of the long arm of chromosome 12. We confirm that 12q22-q23.3 is a candidate locus for familial temporal lobe epilepsy with febrile seizures and highlight the role of chromosomal rearrangements in patients with epilepsy and intellectual disability. Copyright © 2017 British Epilepsy Association. Published by Elsevier Ltd. All rights reserved.

  17. Arterial supply of the thoracic lobes of the thymus in dogs of the Great Dane race.

    Directory of Open Access Journals (Sweden)

    Rosana Marques Silva

    2007-09-01

    Full Text Available The origins, numbers and type of arterial branches responsible for the blood supply of thoracic lobes of the thymus were studied in 28 stillborn dogs of the Great Dane, of which 18 were males and 10 were females. The arterial systems of these animals were filled with aqueous solution of Neoprene Latex “450”, 50%. After, the specimens were fixed in 10% formaldehyde aqueous solution. The lobes of the thymus were supplied by direct or indirect arterial branches coming from the right and left internal thoracic arteries, pericardiacophrenicas arteries, right and left costocervicais trunks, and left subclavian artery. The left subclavian artery and brachiocephalic trunk emitted direct branches towards the left thoracic lobe of the thymus.

  18. Prenatal ultrasound and MRI findings of temporal and occipital lobe dysplasia in a twin with achondroplasia.

    Science.gov (United States)

    Pugash, D; Lehman, A M; Langlois, S

    2014-09-01

    Thanatophoric dysplasia, hypochondroplasia and achondroplasia are all caused by FGFR3 (fibroblast growth factor receptor 3) mutations. Neuropathological findings of temporal lobe dysplasia are found in thanatophoric dysplasia, and temporal and occipital lobe abnormalities have been described recently in brain imaging studies of children with hypochondroplasia. We describe twins discordant for achondroplasia, in one of whom the prenatal diagnosis was based on ultrasound and fetal MRI documentation of temporal and occipital lobe abnormalities characteristic of hypochondroplasia, in addition to the finding of short long bones. Despite the intracranial findings suggestive of hypochondroplasia, achondroplasia was confirmed following postnatal clinical and genetic testing. These intracranial abnormalities have not been previously described in a fetus with achondroplasia. Copyright © 2014 ISUOG. Published by John Wiley & Sons Ltd.

  19. Age at onset of epilepsy as a determinant of intellectual impairment in temporal lobe epilepsy.

    Science.gov (United States)

    Kaaden, Sabine; Helmstaedter, Christoph

    2009-06-01

    Intellectual impairment in addition to memory problems in temporal lobe epilepsy (TLE) has been postulated to be a result of a mental decline caused by chronic epilepsy. Longer duration, however, is often confounded with earlier age at onset of epilepsy (AOE). IQ and memory were evaluated in 188 patients (age>16) with TLE with an AOE before age 14 (N=91) or after age 15 (N=97). Earlier AOE did not differentially affect memory aspects more associated with temporomesial structures, but it negatively affected IQ and aspects of memory that are more related to temporolateral and extratemporal lobe structures. As earlier AOE was also associated with lower educational levels and because one may not assume that these are lost with chronicity of epilepsy, the results can be interpreted as reflecting developmental hindrance of extratemporal lobe functions in early-onset TLE rather than cognitive decline due to a longer duration of epilepsy.

  20. Fornix and medial temporal lobe lesions lead to comparable deficits in complex visual perception.

    Science.gov (United States)

    Lech, Robert K; Koch, Benno; Schwarz, Michael; Suchan, Boris

    2016-05-04

    Recent research dealing with the structures of the medial temporal lobe (MTL) has shifted away from exclusively investigating memory-related processes and has repeatedly incorporated the investigation of complex visual perception. Several studies have demonstrated that higher level visual tasks can recruit structures like the hippocampus and perirhinal cortex in order to successfully perform complex visual discriminations, leading to a perceptual-mnemonic or representational view of the medial temporal lobe. The current study employed a complex visual discrimination paradigm in two patients suffering from brain lesions with differing locations and origin. Both patients, one with extensive medial temporal lobe lesions (VG) and one with a small lesion of the anterior fornix (HJK), were impaired in complex discriminations while showing otherwise mostly intact cognitive functions. The current data confirmed previous results while also extending the perceptual-mnemonic theory of the MTL to the main output structure of the hippocampus, the fornix. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  1. Photogrammetric and Global Positioning System Measurements of Active Pahoehoe Lava Lobe Emplacement on Kilauea, Hawaii

    Science.gov (United States)

    Hamilton, Christopher W.; Glaze, Lori S.; James, Mike R.; Baloga, Stephen M.; Fagents, Sarah A.

    2012-01-01

    Basalt is the most common rock type on the surface of terrestrial bodies throughout the solar system and -- by total volume and areal coverage -- pahoehoe flows are the most abundant form of basaltic lava in subaerial and submarine environments on Earth. A detailed understanding of pahoehoe emplacement processes is necessary for developing accurate models of flow field development, assessing hazards associated with active lava flows, and interpreting the significance of lava flow morphology on Earth and other planetary bodies. Here, we examine the active emplacement of pahoehoe lobes along the margins of the Hook Flow from Pu'u 'O'o on Kilauea, Hawaii. Topographic data were acquired between 21 and 23 February 2006 using stereo-imaging and differential global positing system (DGPS) measurements. During this time, the average discharge rate for the Hook Flow was 0.01-0.05 cubic m/s. Using stereogrammetric point clouds and interpolated digital terrain models (DTMs), active flow fronts were digitized at 1 minute intervals. These areal spreading maps show that the lava lobe grew by a series of breakouts tha t broadly fit into two categories: narrow (0.2-0.6 m-wide) toes that grew preferentially down-slope, and broad (1.4-3.5 m-wide) breakouts that formed along the sides of the lobe, nearly perpendicular to the down-flow axis. These lobes inflated to half of their final thickness within approx 5 minutes, with a rate of inflation that generally deceased with time. Through a combination of down-slope and cross-slope breakouts, lobes developed a parabolic cross-sectional shape within tens of minutes. We also observed that while the average local discharge rate for the lobe was generally constant at 0.0064 +/- 0.0019 cubic m/s, there was a 2 to 6 fold increase in the areal coverage rate every 4.1 +/- 0.6 minutes. We attribute this periodicity to the time required for the dynamic pressurization of the liquid core of the lava lobe to exceed the cooling-induced strength of the

  2. Use of statistical parametric mapping of 18F-FDG-PET in frontal lobe epilepsy

    International Nuclear Information System (INIS)

    Plotkin, M.; Amthauer, H.; Luedemann, L.; Hartkop, E.; Ruf, J.; Gutberlet, M.; Bertram, H.; Felix, R.; Venz, St.; Merschhemke, M.; Meencke, H.-J.

    2003-01-01

    Aim: Evaluation of the use of statistical parametrical mapping (SPM) of FDG-PET for seizure lateralization in frontal lobe epilepsy. Patients: 38 patients with suspected frontal lobe epilepsy supported by clinical findings and video-EEG monitoring. Method: Statistical parametrical maps were generated by subtraction of individual scans from a control group, formed by 16 patients with negative neurological/psychiatric history and no abnormalities in the MR scan. The scans were also analyzed visually as well as semiquantitatively by manually drawn ROIs. Results: SPM showed a better accordance to the results of surface EEG monitoring compared with visual scan analysis and ROI quantification. In comparison with intracranial EEG recordings, the best performance was achieved by combining the ROI based quantification with SPM analysis. Conclusion: These findings suggest that SPM analysis of FDG-PET data could be a useful as complementary tool in the evaluation of seizure focus lateralization in patients with supposed frontal lobe epilepsy. (orig.)

  3. The Lobe Fissure Tracking by the Modified Ant Colony Optimization Framework in CT Images

    Directory of Open Access Journals (Sweden)

    Chii-Jen Chen

    2014-11-01

    Full Text Available Chest computed tomography (CT is the most commonly used technique for the inspection of lung lesions. However, the lobe fissures in lung CT is still difficult to observe owing to its imaging structure. Therefore, in this paper, we aimed to develop an efficient tracking framework to extract the lobe fissures by the proposed modified ant colony optimization (ACO algorithm. We used the method of increasing the consistency of pheromone on lobe fissure to improve the accuracy of path tracking. In order to validate the proposed system, we had tested our method in a database from 15 lung patients. In the experiment, the quantitative assessment shows that the proposed ACO method achieved the average F-measures of 80.9% and 82.84% in left and right lungs, respectively. The experiments indicate our method results more satisfied performance, and can help investigators detect lung lesion for further examination.

  4. Gray, White Matter Concentration Changes and Their Correlation with Heterotopic Neurons in Temporal Lobe Epilepsy

    Energy Technology Data Exchange (ETDEWEB)

    Tae, Woo Suk; Joo, Eun Yun; Kim, Sung Tae; Hong, Seung Bong [Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of)

    2010-02-15

    To identify changes in gray and white matter concentrations (GMC, WMC), and their relation to heterotopic neuron numbers in mesial temporal lobe epilepsy (mTLE). The gray matter or white matter concentrations of 16 left and 15 right mTLE patients who achieved an excellent surgical outcome were compared with those of 24 healthy volunteers for the left group and with 23 healthy volunteers for the right group, by optimized voxel-based morphometry using unmodulated and modulated images. A histologic count of heterotopic neurons was obtained in the white matter of the anterior temporal lobe originating from the patients' surgical specimens. In addition, the number of heterotopic neurons were tested to determine if there was a correlation with the GMC or WMC. The GMCs of the left and right mTLE groups were reduced in the ipsilateral hippocampi, bilateral thalami, precentral gyri, and in the cerebellum. The WMCs were reduced in the ipsilateral white matter of the anterior temporal lobe, bilateral parahippocampal gyri, and internal capsules, but increased in the pons and bilateral precentral gyri. The heterotopic neuron counts in the left mTLE group showed a positive correlation (r = 0.819, p < 0.0001) with GMCs and a negative correlation (r = - 0.839, p < 0.0001) with WMCs in the white matter of the anterior temporal lobe. The present study shows the abnormalities of the cortico-thalamo- hippocampal network including a gray matter volume reduction in the anterior frontal lobes and an abnormality of brain tissue concentration in the pontine area. Furthermore, heterotopic neuron numbers were significantly correlated with GMC or WMC in the left white matter of anterior temporal lobe.

  5. Ictal spitting in left temporal lobe epilepsy: report of three cases.

    Science.gov (United States)

    Caboclo, Luís Otávio Sales Ferreira; Miyashira, Flavia Saori; Hamad, Ana Paula Andrade; Lin, Katia; Carrete, Henrique; Sakamoto, Américo Ceiki; Yacubian, Elza Márcia Targas

    2006-09-01

    Ictal spitting is rarely reported in patients with epilepsy. More often it is observed in patients with temporal lobe epilepsy (TLE) and is presumed to be a lateralizing sign to language nondominant hemisphere. We report three patients with left TLE who had ictal spitting registered during prolonged video-EEG monitoring. Medical charts of all patients with medically refractory partial epilepsy submitted to prolonged video-EEG monitoring in the Epilepsy Unit at UNIFESP during a 3-year period were reviewed, in search of reports of ictal spitting. The clinical, neurophysiological and neuroimaging data of the identified patients were reviewed. Among 136 patients evaluated with prolonged video-EEG monitoring, three (2.2%) presented spitting automatisms during complex partial seizures. All of them were right-handed, and had clear signs of left hippocampal sclerosis on MRI. In two patients, in all seizures in which ictal spitting was observed, EEG seizure onset was seen in the left temporal lobe. In the third patient, ictal onset with scalp electrodes was observed in the right temporal lobe, but semi-invasive monitoring with foramen ovale electrodes revealed ictal onset in the left temporal lobe, confirming false lateralization in surface records. The three patients became seizure-free following left anterior temporal lobectomy. Ictal spitting is a rare finding in patients with epilepsy, and may be considered a localizing sign of seizure onset in the temporal lobe. It may be observed in seizures originating from the left temporal lobe, and thus should not be considered a lateralizing sign of nondominant TLE.

  6. Cognitive Functioning in Temporal Lobe Epilepsy: A BOLD-fMRI Study.

    Science.gov (United States)

    Guo, Lili; Bai, Genji; Zhang, Hui; Lu, Daoyan; Zheng, Jiyong; Xu, Gang

    2017-12-01

    We aimed to analyze the association between resting-state functional magnetic resonance imaging (re-fMRI) and cognitive function (including language, executive, and memory functions) in temporal lobe epilepsy (TLE) patients, which will help to explore the mechanism of brain function in patients. 15 TLE patients and 15 non-TLE patients were recruited. All subjects underwent neuropsychological testing and memory functional evaluation. Changes in verbal intelligence quotient (VIQ), performance intelligence quotient (PIQ), full intelligence quotient (FIQ), and memory quotient (MQ) were compared between two groups. Re-fMRI data were also collected from two groups to evaluate these changes. Each individual score of neuropsychological testing and memory functional evaluation were higher in control group, which was statistically different (all P temporal gyrus back, right superior temporal gyrus, left cerebellum, left angular gyrus, left wedge anterior lobe, and left central back; while the negatively activated brain regions were left prefrontal, right cerebellum, right corner back, and right anterior cingulate gyrus. During the language task, the activated brain regions of the TLE patients were right prefrontal lobe, the lateral temporal gyri, the left cerebellum, left cornu laterale gyrus, left precuneus, and the left postcentral gyrus, whereas the negatively activated brain areas were the left prefrontal cortex, the right cerebellum, right cornu laterale gyrus, and the right anterior cingulate gyrus. During the executive task, epilepsy patients showed activation difference in right prefrontal and right frontal lobe and right brain, left superior temporal gyrus, and right cerebellum anterior lobe compared with the control group; no negatively activated differences in brain areas. During the memory task, the difference lay in bilateral anterior cingulate gyrus and bilateral wedge anterior lobe while the negatively activated brain areas were the left inferior frontal

  7. Cognitive sequelae in survivors of traumatic frontal lobe injury: comparison between mild and moderate injury effects

    International Nuclear Information System (INIS)

    Anjum, A.; Ahmad, W.; Tahir, M. A.

    2017-01-01

    Objective: To determine the frequency of cognitive deficits in the survivors of traumatic frontal lobe injury of mild to moderate severity. Study Design: Mix method study. Place and Duration of Study: Nishter Hospital Multan, Bahawal Victoria Hospital, Bahawalpur and Sheikh Zaid Hospital Rahim Yar Khan, from Sep 2010 to Jun 2011. Material and Methods: The sample consisted of 55 participants. Fifteen of these were taken from healthy population with the age range of 20-30 years (Mean = 25.7 ± SD = 4.6) and 40 participants were medically documented patients of frontal lobe injury of mild (20) to moderate (20) severity. The age range of mild traumatic frontal lobe injury patients was 20-32 years (Mean= 26.5 ± SD = 4.9). The age range of moderate severity patients was also 20-32 years (Mean= 26.4 ± SD = 5.0). Wechsler Adult Intelligence Scale revised and case history interview were administered to determine cognitive deficits following traumatic frontal lobe injury. Results: Statistical test, one way analysis was used to compare the performance of all these three (control, mild and moderate) groups. Results of present study reflected that cognitive deficits like memory deficits, language problems, trouble in concentrating and difficulty in planning are the major consequences of traumatic frontal lobe injury. Conclusion: To conclude, frontal lobe injury patients not only showed poor performance in clinically-driven structured and comprehensive memory tests when they were compared with healthy people but their performance also varied according to the severity of injury. (author)

  8. Strong reduction of spectral heterogeneity in gold bipyramids for single-particle and single-molecule plasmon sensing.

    Science.gov (United States)

    Peters, S M E; Verheijen, M A; Prins, M W J; Zijlstra, P

    2016-01-15

    Single metal nanoparticles are attractive biomolecular sensors. Binding of analyte to a functional particle results in a plasmon shift that can be conveniently monitored in a far-field optical microscope. Heterogeneities in spectral properties of individual particles in an ensemble affect the reliability of a single-particle plasmon sensor, especially when plasmon shifts are monitored in real-time using a fixed irradiation wavelength. We compare the spectral heterogeneity of different plasmon sensor geometries (gold nanospheres, nanorods, and bipyramids) and correlate this to their size and aspect-ratio dispersion. We show that gold bipyramids exhibit a strongly reduced heterogeneity in aspect ratio and plasmon wavelength compared to commonly used gold nanorods. We show that this translates into a significantly improved homogeneity of the response to molecular binding without compromising single-molecule sensitivity.

  9. Evidence of Neuronal Injury Outside the Medial Temporal Lobe in Temporal Lobe Epilepsy:N-Acetylaspartate Concentration Reductions Detected with Multisection Proton MR Spectroscopic Imaging—Initial Experience

    Science.gov (United States)

    Vermathen, Peter; Laxer, Kenneth D.; Schuff, Norbert; Matson, Gerald B.; Weiner, Michael W.

    2009-01-01

    PURPOSE To determine whether magnetic resonance (MR) spectroscopic imaging reveals metabolic changes, especially decreased N-acetylaspartate (NAA) concentrations outside the medial temporal lobe in patients with mesial temporal lobe epilepsy (TLE), consistent with neuropathologic findings of extratemporal neuronal impairment. MATERIALS AND METHODS Eleven patients with mesial TLE and 13 control subjects were examined with multisection MR spectroscopic imaging. Three MR spectroscopic imaging sections were acquired. Thirteen brain regions in each hemisphere and the midbrain were analyzed in each patient, and the NAA to creatine-phosphocreatine (Cr) plus choline-containing compounds (Ch) (NAA/[Cr + Ch]) ratios were determined. In addition, hemispheric and whole-brain values were calculated and statistically analyzed. RESULTS The NAA/(Cr + Ch) ratio in the ipsilateral hippocampus was significantly reduced, compared with that in the contralateral hippocampus (P < .002) and compared with that in control subjects (P < .03), confirming findings in previous studies. In patients, whole-brain NAA/(Cr + Ch) ratio outside the hippocampus was significantly lower than that in control subjects (P < .002). For the ipsilateral hemisphere in patients, NAA/(Cr + Ch) ratio was significantly lower than that in control subjects (P < .0002). Comparisons between individual brain regions revealed trends toward lower NAA/(Cr + Ch) ratios in many areas of the ipsilateral and, to a lesser extent, the contralateral hemisphere outside the hippocampus and temporal lobe, suggesting diffuse impairment. CONCLUSION Results suggest that repeated seizure activity damages neurons outside of the seizure focus. PMID:12511690

  10. Ictal asystole: A rare cardiac manifestation of temporal lobe epilepsy, treated with epilepsy surgery.

    Science.gov (United States)

    Ravat, Shreyas Hasmukh; Bhatti, Amit Ashok; Shah, Mansi Viraj; Muzumdar, Dattatraya P; Ravat, Sangeeta Hasmukh

    2017-01-01

    Seizures are associated with fascinatingly varied cardiac and autonomic manifestations, of which ictal tachycardia is common, and asystole and bradycardia are rare. Ictal asystole (IA), an often unsought autonomic phenomenon, occurs most commonly with temporal followed by frontal lobe seizures. Prolonged IA may lead to cerebral anoxic ischemia. As the mysteries of sudden unexplained death in epilepsy are unraveled, it is quite possible that the key to it lays within these seizure-induced cardiac rhythm abnormalities. We present a case of a young male with temporal lobe epilepsy due to left mesial temporal sclerosis with prolonged IA, which was successfully managed with epilepsy surgery.

  11. Brain metabolite changes in alcoholism: Localized proton magnetic resonance spectroscopy study of the occipital lobe

    Energy Technology Data Exchange (ETDEWEB)

    Modi, Shilpi; Bhattacharya, Manisha; Kumar, Pawan [NMR Research Centre, Institute of Nuclear Medicine and Allied Sciences (DRDO), Lucknow Road, Timarpur, Delhi 110054 (India); Deshpande, Smita N. [Department of Psychiatry, Dr. Ram Manohar Lohia Hospital, New Delhi (India); Tripathi, Rajendra Prasad [NMR Research Centre, Institute of Nuclear Medicine and Allied Sciences (DRDO), Lucknow Road, Timarpur, Delhi 110054 (India); Khushu, Subash, E-mail: skhushu@yahoo.com [NMR Research Centre, Institute of Nuclear Medicine and Allied Sciences (DRDO), Lucknow Road, Timarpur, Delhi 110054 (India)

    2011-07-15

    Chronic alcoholism is associated with altered brain metabolism, morphology and cognitive abilities. Besides deficits in higher order cognitive functions, alcoholics also show a deficit in the processing of basic sensory information viz. visual stimulation. To assess the metabolic changes associated with this deficit, {sup 1}H MRS was carried out in the occipital lobe of alcohol dependents. A significant increase in Cho/Cr ratio (p < 0.015) was observed in occipital lobe in the alcoholic group indicating altered cell membrane metabolism, which may probably be associated with the alterations in the cognitive abilities associated with vision.

  12. Diabetes mellitus, hypertension and medial temporal lobe atrophy: the LADIS study

    DEFF Research Database (Denmark)

    Korf, E S C; van Straaten, E C W; de Leeuw, F-E

    2007-01-01

    was visually scored for the left and right medial temporal lobe (score 0-4), and meaned. RESULTS: Mean age was 73.5 years (sd 5.1), 54% was female. Of the subjects, 15% had DM, and 70% had a history of hypertension. The likelihood of having MTA score 3 was significantly higher in subjects with DM (OR 2.9; 95......HYPOTHESIS: Based on recent findings on the association between vascular risk factors and hippocampal atrophy, we hypothesized that hypertension and diabetes mellitus (DM) are associated with medial temporal lobe atrophy (MTA) in subjects without disability, independent of the severity of white...

  13. Use of opium as antiepileptic in patient with frontal lobe epilepsy: A case report

    Directory of Open Access Journals (Sweden)

    Naresh Nebhinani

    2015-01-01

    Full Text Available Frontal lobe epilepsy (FLE manifests with brief, nocturnal seizures arising in the frontal lobe along with unusual behavioral symptoms or postures, frequently misdiagnosed as a psychogenic nonepileptic seizure (PNES or a sleep disorder. Ancient literature has rarely mentioned the antiepileptic effect of opium or different opioids. Here we are presenting a case with FLE, though initially diagnosed PNES, who had significant relief in his symptoms on using opium, and this led to opium dependence. Index case further emphasizes concern and caution as misdiagnosis of FLE may lead to substance dependenc.

  14. Frontal gray matter abnormalities predict seizure outcome in refractory temporal lobe epilepsy patients.

    Science.gov (United States)

    Doucet, Gaelle E; He, Xiaosong; Sperling, Michael; Sharan, Ashwini; Tracy, Joseph I

    2015-01-01

    Developing more reliable predictors of seizure outcome following temporal lobe surgery for intractable epilepsy is an important clinical goal. In this context, we investigated patients with refractory temporal lobe epilepsy (TLE) before and after temporal resection. In detail, we explored gray matter (GM) volume change in relation with seizure outcome, using a voxel-based morphometry (VBM) approach. To do so, this study was divided into two parts. The first one involved group analysis of differences in regional GM volume between the groups (good outcome (GO), e.g., no seizures after surgery; poor outcome (PO), e.g., persistent postoperative seizures; and controls, N = 24 in each group), pre- and post-surgery. The second part of the study focused on pre-surgical data only (N = 61), determining whether the degree of GM abnormalities can predict surgical outcomes. For this second step, GM abnormalities were identified, within each lobe, in each patient when compared with an ad hoc sample of age-matched controls. For the first analysis, the results showed larger GM atrophy, mostly in the frontal lobe, in PO patients, relative to both GO patients and controls, pre-surgery. When comparing pre-to-post changes, we found relative GM gains in the GO but not in the PO patients, mostly in the non-resected hemisphere. For the second analysis, only the frontal lobe displayed reliable prediction of seizure outcome. 81% of the patients showing pre-surgical increased GM volume in the frontal lobe became seizure free, post-surgery; while 77% of the patients with pre-surgical reduced frontal GM volume had refractory seizures, post-surgery. A regression analysis revealed that the proportion of voxels with reduced frontal GM volume was a significant predictor of seizure outcome (p = 0.014). Importantly, having less than 1% of the frontal voxels with GM atrophy increased the likelihood of being seizure-free, post-surgery, by seven times. Overall, our results suggest that using pre

  15. Pleomorphic adenoma of deep lobe of parotid: A rare pediatric tumor

    Directory of Open Access Journals (Sweden)

    Sandesh V. Parelkar

    2016-04-01

    Full Text Available Salivary gland neoplasms are extremely rare in children and comprise less than 1% of all pediatric neoplasms. Benign neoplasms account for 60% of these salivary tumors in children. They are most commonly vascular in origin with parotid glands being affected commonly. Pleomorphic adenoma is common in adults; it is extremely rare in pediatric age group. We report a 9 year old girl with a parotid region swelling; suspected to be a pleomorphic adenoma of the superficial lobe of parotid. However, it was arising from the deep lobe & hence was managed with an enucleation of the tumor with no evidence of recurrence after 3 years of follow up.

  16. Balint′s Syndrome As a Manifestation of Solitary Right Occipital Lobe Metastasis

    Directory of Open Access Journals (Sweden)

    Sarat Chandra P

    1998-01-01

    Full Text Available Balint′s syndrome is a rare clinical condition characterized by a triad of occulomotor apraxia (psychic paralysis of gaze, optic ataxia and visual inattention and usually follows bilateral parieto-occipital lesions. We report this syndrome occurring in a patient with a solitary metastasis in right occipital lobe. To the best of our knowledge it has not been previously described in English literature. Pressure over the opposite occipital lobe due to mass effect, diaschisis and extension of edema along the corpus callosum involvement may contribute to this exceptional phenomenon.

  17. Radiosurgery for Medial Temporal Lobe Epilepsy Resulting from Mesial Temporal Sclerosis.

    Science.gov (United States)

    Gianaris, Thomas; Witt, Thomas; Barbaro, Nicholas M

    2016-01-01

    Medial temporal lobe epilepsy associated with mesial temporal sclerosis (MTS) is perhaps the most well-defined epilepsy syndrome that is responsive to structural interventions such as surgery. Several minimally invasive techniques have arisen that provide additional options for the treatment of MTS while potentially avoiding many of open surgery's associated risks. By evading these risks, they also open up treatment options to patients who otherwise are poor surgical candidates. Radiosurgery is one of the most intensively studied of these alternatives and has found a growing role in the treatment of medial temporal lobe epilepsy. Copyright © 2016 Elsevier Inc. All rights reserved.

  18. FDTD analysis of temperature elevation in the lens of human and rabbit models due to near-field and far-field exposures at 2.45 GHz

    International Nuclear Information System (INIS)

    Oizumi, T.; Laakso, I.; Hirata, A.; Fujiwara, O.; Watanabe, S.; Taki, M.; Kojima, M.; Sasaki, H.; Sasaki, K.

    2013-01-01

    The eye is said to be one of the most sensitive organs to microwave heating. According to previous studies, the possibility of microwave-induced cataract formation has been experimentally investigated in rabbit and monkey eyes, but not for the human eye due to ethical reasons. In the present study, the temperature elevation in the lens, the skin around the eye and the core temperature of numerical human and rabbit models for far-field and near-field exposures at 2.45 GHz are investigated. The temperature elevations in the human and rabbit models were compared with the threshold temperatures for inducing cataracts, thermal pain in the skin and reversible health effects such as heat exhaustion or heat stroke. For plane-wave exposure, the core temperature elevation is shown to be essential both in the human and in the rabbit models as suggested in the international guidelines and standards. For localised exposure of the human eye, the temperature elevation of the skin was essential, and the lens temperature did not reach its threshold for thermal pain. On the other hand, the lens temperature elevation was found to be dominant for the rabbit eye. (authors)

  19. A Possible Source Mechanism of the 1946 Unimak Alaska Far-Field Tsunami: Uplift of the Mid-Slope Terrace Above a Splay Fault Zone

    Science.gov (United States)

    von Huene, Roland; Miller, John J.; Klaeschen, Dirk; Dartnell, Peter

    2016-12-01

    In 1946, megathrust seismicity along the Unimak segment of the Alaska subduction zone generated the largest ever recorded Alaska/Aleutian tsunami. The tsunami severely damaged Pacific islands and coastal areas from Alaska to Antarctica. It is the charter member of "tsunami" earthquakes that produce outsized far-field tsunamis for the recorded magnitude. Its source mechanisms were unconstrained by observations because geophysical data for the Unimak segment were sparse and of low resolution. Reprocessing of legacy geophysical data reveals a deep water, high-angle reverse or splay thrust fault zone that leads megathrust slip upward to the mid-slope terrace seafloor rather than along the plate boundary toward the trench axis. Splay fault uplift elevates the outer mid-slope terrace and its inner area subsides. Multibeam bathymetry along the splay fault zone shows recent but undated seafloor disruption. The structural configuration of the nearby Semidi segment is similar to that of the Unimak segment, portending generation of a future large tsunami directed toward the US West coast.

  20. A possible source mechanism of the 1946 Unimak Alaska far-field tsunami, uplift of the mid-slope terrace above a splay fault zone

    Science.gov (United States)

    von Huene, Roland E.; Miller, John J.; Klaeschen, Dirk; Dartnell, Peter

    2016-01-01

    In 1946, megathrust seismicity along the Unimak segment of the Alaska subduction zone generated the largest ever recorded Alaska/Aleutian tsunami. The tsunami severely damaged Pacific islands and coastal areas from Alaska to Antarctica. It is the charter member of “tsunami” earthquakes that produce outsized far-field tsunamis for the recorded magnitude. Its source mechanisms were unconstrained by observations because geophysical data for the Unimak segment were sparse and of low resolution. Reprocessing of legacy geophysical data reveals a deep water, high-angle reverse or splay thrust fault zone that leads megathrust slip upward to the mid-slope terrace seafloor rather than along the plate boundary toward the trench axis. Splay fault uplift elevates the outer mid-slope terrace and its inner area subsides. Multibeam bathymetry along the splay fault zone shows recent but undated seafloor disruption. The structural configuration of the nearby Semidi segment is similar to that of the Unimak segment, portending generation of a future large tsunami directed toward the US West coast.

  1. Differentiation of cryptogenic lateral from mesial temporal lobe epilepsy using regional asymmetric index of F-18-FDG PET

    International Nuclear Information System (INIS)

    Song, H. C.; Lee, D. S.; Lee, S. K.; Jeong, J. M.; Jeong, Z. K.; Lee, M. C.; Ko, C. S.

    1997-01-01

    We tried to find the possibility of utilization of F-18-FDG PET to differentiate lateral (neocortical) from mesial temporal lobe epilepsy(TLE) if we adopted quantitative comparison of regional metabolic activities using asymmetric index. We studied 22 pathologically proven mesial TLE(group C in Figure), and 27 lateral TLE patients. Lateral TLE patients were normal on MR(cryptogenic: 15; group A) or had structural lesions (12: group B). Asymmetric index (AI) was calculated as (ipsilateral -contralateral) / (ipsilateral + contralateral ) x 200. AI of medial lobe of cryptogenic lateral TLE was not decreased (-4.66.2, > 0.05) and AI of medial lobe of cryptogenic lateral TLE was not decreased (-4.66.2, >0.05) and AI of lateral lobe was decreased (-13.68.9). AI of medial and lateral lobes of mesial TLE was decreased (-3.44.7 and -16.58.9, respectively). AI of medial lobe of lesional lateral TLE was -7.39.1 (p<0.05 compared with mesial TEL). It was evident that lateral lobe of lesional lateral TLE had metabolic defect or decrease (AI: -21.410.4). While we could not find difference of metabolic activity in lateral temporal lobes between cryptogenic lateral TLE and mesial TLE patients, the difference of metabolic activity was significant in medial temporal lobes which was revealed by AI quantitation. An AI value larger than -10 (cutoff: AI) predicted positively for lateral TLE(PPV:80%) and negatively for mesial TLE(NPV:77%). Asymmetry of metabolic activity in medial and not in lateral lobe of temporal lobe could give hints about whether the epileptogenic zones were mesial or lateral

  2. Exploiting of the Compression Methods for Reconstruction of the Antenna Far-Field Using Only Amplitude Near-Field Measurements

    Directory of Open Access Journals (Sweden)

    J. Puskely

    2010-06-01

    Full Text Available The novel approach exploits the principle of the conventional two-plane amplitude measurements for the reconstruction of the unknown electric field distribution on the antenna aperture. The method combines a global optimization with a compression method. The global optimization method (GO is used to minimize the functional, and the compression method is used to reduce the number of unknown variables. The algorithm employs the Real Coded Genetic Algorithm (RCGA as the global optimization approach. The Discrete Cosine Transform (DCT and the Discrete Wavelet Transform (DWT are applied to reduce the number of unknown variables. Pros and cons of methods are investigated and reported for the solution of the problem. In order to make the algorithm faster, exploitation of amplitudes from a single scanning plane is also discussed. First, the algorithm is used to obtain an initial estimate. Subsequently, the common Fourier iterative algorithm is used to reach global minima with sufficient accuracy. The method is examined measuring the dish antenna.

  3. Thalamic glucose metabolism in temporal lobe epilepsy measured with 18F-FDG positron emission tomography (PET)

    NARCIS (Netherlands)

    Khan, N; Leenders, KL; Hajek, M; Maguire, P; Missimer, J; Wieser, HG

    1997-01-01

    Thalamic glucose metabolism has been studied in 24 patients suffering from temporal lobe epilepsy (TLE) using interictal F-18-fluorodeoxyglucose (FDG) positron emission tomography (PET). A total of 17 patients had a unilateral TL seizure onset, 11 of these patients had a mesial temporal lobe

  4. Identifying bvFTD Within the Wide Spectrum of Late Onset Frontal Lobe Syndrome: A Clinical Approach

    NARCIS (Netherlands)

    Krudop, W.A.; Kerssens, C.J.; Dols, A.; Prins, N.D.; Moller, C.; Schouws, S.N.T.M.; van der Flier, W.M.; Scheltens, P.; Sikkes, S.A.M.; Stek, M.L.; Pijnenburg, Y.A.L.

    2015-01-01

    Objective The behavioral variant of frontotemporal dementia (bvFTD) can be difficult to diagnose because of the extensive differential diagnosis, including many other diseases presenting with a frontal lobe syndrome. We aimed to identify the diagnostic spectrum causing a late onset frontal lobe

  5. Episodic memory and the medial temporal lobe: not all it seems. Evidence from the temporal variants of frontotemporal dementia

    NARCIS (Netherlands)

    Pleizier, C.M.; van der Vlies, A.E.; Koedam, E.L.G.E.; Koene, T.; Barkhof, F.; van der Flier, W.M.; Scheltens, P.; Pijnenburg, Y.A.L.

    2012-01-01

    Background: Disproportionate medial temporal lobe atrophy (MTA) is an early finding in Alzheimer's disease (AD). Episodic memory impairment in AD is associated with the degree of MTA. Episodic memory impairment and MTA are also found in semantic dementia (SD) and in right temporal lobe atrophy

  6. The anterior temporal lobes support residual comprehension in Wernicke’s aphasia

    Science.gov (United States)

    Robson, Holly; Zahn, Roland; Keidel, James L.; Binney, Richard J.; Sage, Karen; Lambon Ralph, Matthew A.

    2014-01-01

    Wernicke’s aphasia occurs after a stroke to classical language comprehension regions in the left temporoparietal cortex. Consequently, auditory–verbal comprehension is significantly impaired in Wernicke’s aphasia but the capacity to comprehend visually presented materials (written words and pictures) is partially spared. This study used functional magnetic resonance imaging to investigate the neural basis of written word and picture semantic processing in Wernicke’s aphasia, with the wider aim of examining how the semantic system is altered after damage to the classical comprehension regions. Twelve participants with chronic Wernicke’s aphasia and 12 control participants performed semantic animate–inanimate judgements and a visual height judgement baseline task. Whole brain and region of interest analysis in Wernicke’s aphasia and control participants found that semantic judgements were underpinned by activation in the ventral and anterior temporal lobes bilaterally. The Wernicke’s aphasia group displayed an ‘over-activation’ in comparison with control participants, indicating that anterior temporal lobe regions become increasingly influential following reduction in posterior semantic resources. Semantic processing of written words in Wernicke’s aphasia was additionally supported by recruitment of the right anterior superior temporal lobe, a region previously associated with recovery from auditory-verbal comprehension impairments. Overall, the results provide support for models in which the anterior temporal lobes are crucial for multimodal semantic processing and that these regions may be accessed without support from classic posterior comprehension regions. PMID:24519979

  7. Five-Year Neuropsychological Outcome after Stereotactic Radiofrequency Amygdalohippocampectomy for Mesial Temporal Lobe Epilepsy: Longitudinal Study

    Czech Academy of Sciences Publication Activity Database

    Krámská, L.; Vojtěch, Z.; Lukavský, Jiří; Stará, M.; Malíková, H.

    Roč. 95, č. 3 ( 2017 ), s. 149-157 ISSN 1011-6125 Institutional support: RVO:68081740 Keywords : Cognitive outcome * Memory * Temporal lobe epilepsy * Stereotactic surgery Subject RIV: FH - Neurology OBOR OECD: Psychology (including human - machine relations) Impact factor: 1.692, year: 2016

  8. Carbamazepine reduces memory induced activation of mesial temporal lobe structures: a pharmacological fMRI-study

    Directory of Open Access Journals (Sweden)

    Okujava Michael

    2001-11-01

    Full Text Available Abstract Background and Purpose It is not known whether carbamazepine (CBZ; a drug widely used in neurology and psychiatry influences the blood oxygenation level dependent (BOLD contrast changes induced by neuronal activation and measured by functional MRI (fMRI. We aimed to investigate the influence of CBZ on memory induced activation of the mesial temporal lobes in patients with symptomatic temporal lobe epilepsy (TLE. Material and Methods Twenty-one individual patients with refractory symptomatic TLE with different CBZ serum levels and 20 healthy controls were studied using BOLD fMRI. Mesial temporal lobe (MTL activation was induced by a task that is based on the retrieval of individually familiar visuo-spatial knowledge. The extent of significant MTL fMRI activation was measured and correlated with the CBZ serum level. Results In TLE patients, the extent of significant fMRI activation over both MTL was negatively correlated to the CBZ serum level (Spearman r = -0.654, P Conclusions In TLE patients, carbamazepine reduces the fMRI-detectable changes within the mesial temporal lobes as induced by effortful memory retrieval. FMRI appears to be suitable to study the effects of chronic drug treatment in patients with epilepsy.

  9. Comparison of elasticity values of the right lobe of the liver of normal ...

    African Journals Online (AJOL)

    Introduction: Shear wave elastography is a method for the measurement of tissue stiffness. The advantage of this method is that its outcome is not operator dependent. Our aim was to compare the elastiscity values of the right lobe of the liver of normal weighted and morbidly obese patients. Materials and Methods: The ...

  10. Content-Specific Source Encoding in the Human Medial Temporal Lobe

    Science.gov (United States)

    Awipi, T.; Davachi, L.

    2008-01-01

    Although the medial temporal lobe (MTL) is known to be essential for episodic encoding, the contributions of individual MTL subregions remain unclear. Data from recognition memory studies have provided evidence that the hippocampus supports relational encoding important for later episodic recollection, whereas the perirhinal cortex has been linked…

  11. Medial Temporal Lobe Activity during Source Retrieval Reflects Information Type, Not Memory Strength

    Science.gov (United States)

    Diana, Rachel A.; Yonelinas, Andrew P.; Ranganath, Charan

    2010-01-01

    The medial temporal lobes (MTLs) are critical for episodic memory but the functions of MTL subregions are controversial. According to memory strength theory, MTL subregions collectively support declarative memory in a graded manner. In contrast, other theories assert that MTL subregions support functionally distinct processes. For instance, one…

  12. Clinico-Pathological Correlations of the Frontal Lobe Syndrome : Results of a Large Brain Bank Study

    NARCIS (Netherlands)

    Krudop, Welmoed A; Bosman, Sjanne; Geurts, Jeroen J G; Sikkes, Sietske A M; Verwey, Nicolaas A; Stek, Max L; Scheltens, Philip; Rozemuller, Annemieke J M; Pijnenburg, Yolande A L

    2015-01-01

    AIMS: A clinical frontal lobe syndrome (FLS) is generally attributed to functional or structural disturbances within frontal-subcortical circuits. We studied the distribution of pathological brain changes in FLS. Additionally, the prevalence of FLS among various disorders was studied. METHODS: We

  13. Frontal lobe oxygenation is maintained during hypotension following propofol-fentanyl anesthesia

    DEFF Research Database (Denmark)

    Nissen, P.; Lieshout, J.J. van; Nielsen, H.B.

    2009-01-01

    Near-infrared spectroscopy (NIRS) assesses cerebral oxygen saturation (Sco2) as a balance between cerebral oxygen delivery and consumption. In 71 patients, we evaluated whether marked reduction in mean arterial pressure (MAP) during propofol-fentanyl anesthesia induction affects frontal lobe Sco2...

  14. The Human Ventromedial Frontal Lobe Is Critical for Learning from Negative Feedback

    Science.gov (United States)

    Wheeler, Elizabeth Z.; Fellows, Lesley K.

    2008-01-01

    Are positive and negative feedback weighed in a common balance in the brain, or do they influence behaviour through distinct neural mechanisms? Recent neuroeconomic studies in both human and non-human primates indicate that the ventromedial frontal lobe carries information about both losses and gains, suggesting that this region may encode value…

  15. Performance on the Frontal Assessment Battery is sensitive to frontal lobe damage in stroke patients.

    Science.gov (United States)

    Kopp, Bruno; Rösser, Nina; Tabeling, Sandra; Stürenburg, Hans Jörg; de Haan, Bianca; Karnath, Hans-Otto; Wessel, Karl

    2013-11-16

    The Frontal Assessment Battery (FAB) is a brief battery of six neuropsychological tasks designed to assess frontal lobe function at bedside [Neurology 55:1621-1626, 2000]. The six FAB tasks explore cognitive and behavioral domains that are thought to be under the control of the frontal lobes, most notably conceptualization and abstract reasoning, lexical verbal fluency and mental flexibility, motor programming and executive control of action, self-regulation and resistance to interference, inhibitory control, and environmental autonomy. We examined the sensitivity of performance on the FAB to frontal lobe damage in right-hemisphere-damaged first-ever stroke patients based on voxel-based lesion-behavior mapping. Voxel-based lesion-behavior mapping of FAB performance revealed that the integrity of the right anterior insula (BA13) is crucial for the FAB global composite score, for the FAB conceptualization score, as well as for the FAB inhibitory control score. Furthermore, the FAB conceptualization and mental flexibility scores were sensitive to damage of the right middle frontal gyrus (MFG; BA9). Finally, the FAB inhibitory control score was sensitive to damage of the right inferior frontal gyrus (IFG; BA44/45). These findings indicate that several FAB scores (including composite and item scores) provide valid measures of right hemispheric lateral frontal lobe dysfunction, specifically of focal lesions near the anterior insula, in the MFG and in the IFG.

  16. Frontal lobe epileptic seizures are accompanied by elevated pitch during verbal communication.

    Science.gov (United States)

    Speck, Iva; Echternach, Matthias; Sammler, Daniela; Schulze-Bonhage, Andreas

    2018-01-31

    The objective of our study was to assess alterations in speech as a possible localizing sign in frontal lobe epilepsy. Ictal speech was analyzed in 18 patients with frontal lobe epilepsy (FLE) during seizures and in the interictal period. Matched identical words were analyzed regarding alterations in fundamental frequency (ƒo) as an approximation of pitch. In patients with FLE, ƒo of ictal utterances was significantly higher than ƒo in interictal recordings (p = 0.016). Ictal ƒo increases occurred in both FLE of right and left seizure origin. In contrast, a matched temporal lobe epilepsy (TLE) group showed less pronounced increases in ƒo, and only in patients with right-sided seizure foci. This study for the first time shows significant voice alterations in ictal speech in a cohort of patients with FLE. This may contribute to the localization of the epileptic focus. Increases in ƒo were interestingly found in frontal lobe seizures with origin in either hemisphere, suggesting a bilateral involvement to the planning of speech production, in contrast to a more right-sided lateralization of pitch perception in prosodic processing. Wiley Periodicals, Inc. © 2018 International League Against Epilepsy.

  17. Behavioral profiles in frontal lobe epilepsy: Autobiographic memory versus mood impairment.

    Science.gov (United States)

    Rayner, Genevieve; Jackson, Graeme D; Wilson, Sarah J

    2015-02-01

    Autobiographic memory encompasses the encoding and retrieval of episodes, people, and places encountered in everyday life. It can be impaired in both epilepsy and frontal lobe damage. Here, we performed an initial investigation of how autobiographic memory is impacted by chronic frontal lobe epilepsy (FLE) together with its underlying pathology. We prospectively studied a series of nine consecutive patients with medically refractory FLE, relative to 24 matched healthy controls. Seven of the nine patients had frontal lobe structural abnormalities. Episodic and semantic autobiographic memory functioning was profiled, and factors associated with impaired autobiographic memory were identified among epileptologic, neuroimaging, neuropsychiatric, and cognitive variables including auditory-verbal and visual memory, and the executive function of cognitive control. Results showed that the FLE group experienced significantly higher rates of autobiographic memory and mood disturbance (p frontal lobe seizure activity with its underlying pathology may selectively disrupt large-scale cognitive or affective networks, giving rise to different neurobehavioral profiles that may be used to inform clinical management. Wiley Periodicals, Inc. © 2015 International League Against Epilepsy.

  18. Cognitive Functioning after Medial Frontal Lobe Damage Including the Anterior Cingulate Cortex: A Preliminary Investigation

    Science.gov (United States)

    Baird, Amee; Dewar, Bonnie-Kate; Critchley, Hugo; Gilbert, Sam J.; Dolan, Raymond J.; Cipolotti, Lisa

    2006-01-01

    Two patients with medial frontal lobe damage involving the anterior cingulate cortex (ACC) performed a range of cognitive tasks, including tests of executive function and anterior attention. Both patients lesions extended beyond the ACC, therefore caution needs to be exerted in ascribing observed deficits to the ACC alone. Patient performance was…

  19. Influence of norepinephrine and phenylephrine on frontal lobe oxygenation during cardiopulmonary bypass in patients with diabetes.

    Science.gov (United States)

    Brassard, Patrice; Pelletier, Claudine; Martin, Mickaël; Gagné, Nathalie; Poirier, Paul; Ainslie, Philip N; Caouette, Manon; Bussières, Jean S

    2014-06-01

    Although utilization of vasopressors recently has been associated with reduced cerebral oxygenation, the influence of vasopressors on cerebral oxygenation during cardiopulmonary bypass in patients with diabetes is unknown. The aim of this study was to document the impact of norepinephrine and phenylephrine utilization on cerebral oxygenation in patients with and without diabetes during cardiopulmonary bypass. Prospective, clinical study. Academic medical center. Fourteen patients with diabetes and 17 patients without diabetes undergoing cardiac surgery. During cardiopulmonary bypass, norepinephrine (diabetics n = 6; non-diabetics n = 8) or phenylephrine (diabetics n = 8; non-diabetics n = 9) was administered intravenously to maintain mean arterial pressure above 60 mmHg. Mean arterial pressure, venous temperature, arterial oxygenation, and frontal lobe oxygenation (monitored by near-infrared spectroscopy) were recorded before anesthesia induction (baseline) and continuously during cardiopulmonary bypass. Frontal lobe oxygenation was lowered to a greater extent in diabetics versus non-diabetics with administration of norepinephrine (-14±13 v 3±12%; pfrontal lobe oxygenation in diabetics but not in patients without diabetes. Administration of phenylephrine also were associated with a trend towards a greater reduction in frontal lobe oxygenation in diabetics. The clinical implications of these findings deserve future consideration. © 2013 Elsevier Inc. All rights reserved.

  20. Bilingual Language Switching and the Frontal Lobes: Modulatory Control in Language Selection.

    Science.gov (United States)

    Meuter, Renata; Humphreys, Glyn; Rumiati, Raffaella

    2002-01-01

    Discusses the brain mechanisms mediating the switching of languages in bilingual subjects. To ascertain the brain mechanisms mediating the control of language switching, switching was examined in a bilingual patient with frontal lobe damage and impaired control processes. (Author/VWL)