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Sample records for 3he-mri study lacunarity

  1. {sup 3}He-MRI in follow-up of lung transplant recipients

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    Gast, Klaus Kurt; Zaporozhan, Julia; Ley, Sebastian; Biedermann, Alexander; Knitz, Frank; Eberle, Balthasar; Schmiedeskamp, Joerg; Heussel, Claus-Peter; Mayer, Eckhard; Schreiber, Wolfgang Guenter; Thelen, Manfred; Kauczor, Hans-Ulrich [Department of Radiology, Johannes Gutenberg University Hospital, Langenbeckstrasse 1, 55131, Mainz (Germany)

    2004-01-01

    The aim of this study was to evaluate the possible contribution of {sup 3}He-MRI to detect obliterative bronchiolitis (OB) in the follow-up of lung transplant recipients. Nine single- and double-lung transplanted patients were studied by an initial and a follow-up {sup 3}He-MRI study. Images were evaluated subjectively by estimation of ventilation defect area and quantitatively by individually adapted threshold segmentation and subsequent calculation of ventilated lung volume. Bronchiolitis obliterans syndrome (BOS) was diagnosed using pulmonary function tests. At {sup 3}He-MRI, OB was suspected if ventilated lung volume had decreased by 10% or more at the follow-up MRI study compared with the initial study. General accordance between pulmonary function testing and {sup 3}He-MRI was good, although subjective evaluation of {sup 3}He-MRI underestimated improvement in ventilation as obtained by pulmonary function tests. The {sup 3}He-MRI indicated OB in 6 cases. According to pulmonary function tests, BOS was diagnosed in 5 cases. All diagnoses of BOS were also detected by {sup 3}He-MRI. In 2 of these 5 cases, {sup 3}He-MRI indicated OB earlier than pulmonary function tests. The results support the hypothesis that {sup 3}He-MRI may be sensitive for early detection of OB and emphasize the need for larger prospective follow-up studies. (orig.)

  2. Oxygen-sensitive {sup 3}He-MRI in bronchiolitis obliterans after lung transplantation

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    Gast, Klaus K. [Klinikum der Johannes Gutenberg-Universitaet, Klinik und Poliklinik fuer diagnostische und interventionelle Radiologie, Mainz (Germany); Biedermann, Alexander [Klinikum der Johannes Gutenberg-Universitaet, 3. Medizinische Klinik, Pulmonologie, Mainz (Germany); Herweling, Annette [Klinikum der Johannes Gutenberg-Universitaet, Klinik fuer Anaesthesiologie, Mainz (Germany); Schreiber, Wolfgang G. [Klinikum der Johannes Gutenberg-Universitaet, Klinik und Poliklinik fuer diagnostische und interventionelle Radiologie, MR-Physik, Mainz (Germany); Schmiedeskamp, Joerg [Max-Planck-Institut fuer Polymerforschung, Mainz (Germany); Mayer, Eckhard [Klinikum der Johannes Gutenberg-Universitaet, Klinik fuer Herz-, Thorax- und Gefaesschirurgie, Mainz (Germany); Heussel, Claus P. [Abteilung fuer Radiologie, Thoraxklinik Heidelberg, Heidelberg (Germany); Markstaller, Klaus; Eberle, Balthasar [Inselspital/Universitaetsspital, Klinik fuer Anaesthesiologie, Bern (Switzerland); Kauczor, Hans-Ulrich [Radiologie, Deutsches Krebsforschungszentrum (DKFZ), Heidelberg (Germany)

    2008-03-15

    Oxygen-sensitive {sup 3}He-MRI was studied for the detection of differences in intrapulmonary oxygen partial pressure (pO{sub 2}) between patients with normal lung transplants and those with bronchiolitis obliterans syndrome (BOS). Using software developed in-house, oxygen-sensitive {sup 3}He-MRI datasets from patients with normal lung grafts (n = 8) and with BOS (n = 6) were evaluated quantitatively. Datasets were acquired on a 1.5-T system using a spoiled gradient echo pulse sequence. Underlying diseases were pulmonary emphysema (n = 10 datasets) and fibrosis (n = 4). BOS status was verified by pulmonary function tests. Additionally, {sup 3}He-MRI was assessed blindedly for ventilation defects. Median intrapulmonary pO{sub 2} in patients with normal lung grafts was 146 mbar compared with 108 mbar in patients with BOS. Homogeneity of pO2 distribution was greater in normal grafts (standard deviation pO2 34 versus 43 mbar). Median oxygen decrease rate during breath hold was higher in unaffected patients (-1.75 mbar/s versus -0.38 mbar/s). Normal grafts showed fewer ventilation defects (5% versus 28%, medians). Oxygen-sensitive {sup 3}He-MRI appears capable of demonstrating differences of intrapulmonary pO2 between normal lung grafts and grafts affected by BOS. Oxygen-sensitive {sup 3}He-MRI may add helpful regional information to other diagnostic techniques for the assessment and follow-up of lung transplant recipients. (orig.)

  3. Linking Ventilation Heterogeneity Quantified via Hyperpolarized 3He MRI to Dynamic Lung Mechanics and Airway Hyperresponsiveness.

    Science.gov (United States)

    Lui, Justin K; Parameswaran, Harikrishnan; Albert, Mitchell S; Lutchen, Kenneth R

    2015-01-01

    Advancements in hyperpolarized helium-3 MRI (HP 3He-MRI) have introduced the ability to render and quantify ventilation patterns throughout the anatomic regions of the lung. The goal of this study was to establish how ventilation heterogeneity relates to the dynamic changes in mechanical lung function and airway hyperresponsiveness in asthmatic subjects. In four healthy and nine mild-to-moderate asthmatic subjects, we measured dynamic lung resistance and lung elastance from 0.1 to 8 Hz via a broadband ventilation waveform technique. We quantified ventilation heterogeneity using a recently developed coefficient of variation method from HP 3He-MRI imaging. Dynamic lung mechanics and imaging were performed at baseline, post-challenge, and after a series of five deep inspirations. AHR was measured via the concentration of agonist that elicits a 20% decrease in the subject's forced expiratory volume in one second compared to baseline (PC20) dose. The ventilation coefficient of variation was correlated to low-frequency lung resistance (R = 0.647, P ventilation heterogeneity. Also, the degree of AHR appears to be dependent on the degree to which baseline airway constriction creates baseline ventilation heterogeneity. HP 3He-MRI imaging may be a powerful predictor of the degree of AHR and in tracking the efficacy of therapy.

  4. Hyperpolarized 3He MRI and 81mKr SPECT in chronic obstructive pulmonary disease

    DEFF Research Database (Denmark)

    Stavngaard, Trine; Søgaard, Lise; Mortensen, J;

    2005-01-01

    was to compare ventilation imaging methods in 26 patients with chronic obstructive pulmonary disease (COPD) and nine lung healthy volunteers. METHODS: HP 3He MRI, 81mKr single-photon emission computed tomography (SPECT), high-resolution computed tomography (HRCT) and pulmonary function tests were performed...... visual defect score (r=0.80, ppulmonary function test and HRCT). The defect scores were largest on 81mKr SPECT (the score on HP 3He MRI...... was one-third less than that on 81mKr SPECT), but the difference was reduced after normalisation for different breathing depths (HP 3He MRI at total lung capacity; 81mKr SPECT at tidal breathing at functional residual capacity). CONCLUSION: HP 3He MRI provides detailed ventilation distribution images...

  5. (3)He MRI in healthy volunteers: preliminary correlation with smoking history and lung volumes.

    Science.gov (United States)

    Guenther, D; Eberle, B; Hast, J; Lill, J; Markstaller, K; Puderbach, M; Schreiber, W G; Hanisch, G; Heussel, C P; Surkau, R; Grossmann, T; Weiler, N; Thelen, M; Kauczor, H U

    2000-06-01

    MRI with hyperpolarized helium-3 ((3)He) provides high-resolution imaging of ventilated airspaces. The first aim of this (3)He-study was to compare observations of localized signal defects in healthy smokers and non-smokers. A second aim was to describe relationships between parameters of lung function, volume of inspired (3)He and signal-to-noise ratio. With Ethics Committee approval and informed consent, 12 healthy volunteers (seven smokers and five non-smokers) were studied. Imaging was performed in a 1.5 T scanner using a two-dimensional FLASH sequence at 30V transmitter amplitude (TR/TE/alpha = 11 ms/4.2 ms/microprocessor-controlled delivery device and imaged during single breath-holds. Images were evaluated visually, and scored using a prospectively defined 'defect-index'. Signal-to-noise ratio of the images were correlated with localization, (3)He volumes and static lung volumes. Due to poor image quality studies of two smokers were not eligible for the evaluation. Smokers differed from non-smokers in total number and size of defects: the 'defect-index' of smokers ranged between 0.8 and 6.0 (median = 1.1), that of non-smokers between 0.1 and 0.8 (median = 0.4). Intraindividually, an anteroposterior gradient of signal-to-noise ratio was apparent. Signal-to-noise ratio correlated with the estimated amount of hyperpolarization administered (r = 0. 77), but not with static lung volumes. We conclude that (3)He MRI is a sensitive measure to detect regional abnormalities in the distribution of ventilation in clinically healthy persons with normal pulmonary function tests.

  6. Lacunar versus non-lacunar syndromes.

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    Micheli, Sara; Corea, Francesco

    2012-01-01

    Small-vessel disease is the accepted most frequent cause of lacunar stroke. The main clinical features seen with lacunar infarcts are motor and/or sensitive deficit, ataxic sign, without cortical involvement. A lacunar syndrome is generally the result of a small deep infarct within the territory of a single perforating artery with the maximum diameter on imaging of 15 mm. Recent studies have demonstrated alternative causes of lacunar stroke other than small-vessel disease (e.g. cardio embolism, atherosclerosis or other causes), especially in large lacunae, with a potential relevance on functional outcome. These findings suggest that lacunar stroke is not always a benign disease. Moreover, clinical features may be significant in terms of disability in lacunae in close proximity to crucial anatomical site. The following chapter reports the classical lacunar syndrome and discusses the debated etiology of lacunar stroke.

  7. Clinical predictors of lacunar syndrome not due to lacunar infarction

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    Comes Emili

    2010-05-01

    Full Text Available Background Lacunar syndrome not due to lacunar infarct is poorly characterised. This single centre, retrospective study was conducted to describe the clinical characteristics of patients with lacunar syndrome not due to lacunar infarct and to identify clinical predictors of this variant of lacunar stroke. Methods A total of 146 patients with lacunar syndrome not due to lacunar infarction were included in the "Sagrat Cor Hospital of Barcelona Stroke Registry" during a period of 19 years (1986-2004. Data from stroke patients are entered in the stroke registry following a standardized protocol with 161 items regarding demographics, risk factors, clinical features, laboratory and neuroimaging data, complications and outcome. The characteristics of these 146 patients with lacunar syndrome not due to lacunar infarct were compared with those of the 733 patients with lacunar infarction. Results Lacunar syndrome not due to lacunar infarct accounted for 16.6% (146/879 of all cases of lacunar stroke. Subtypes of lacunar syndromes included pure motor stroke in 63 patients, sensorimotor stroke in 51, pure sensory stroke in 14, atypical lacunar syndrome in 9, ataxic hemiparesis in 5 and dysarthria-clumsy hand in 4. Valvular heart disease, atrial fibrillation, sudden onset, limb weakness and sensory symptoms were significantly more frequent among patients with lacunar syndrome not due to lacunar infarct than in those with lacunar infarction, whereas diabetes was less frequent. In the multivariate analysis, atrial fibrillation (OR = 4.62, sensorimotor stroke (OR = 4.05, limb weakness (OR = 2.09, sudden onset (OR = 2.06 and age (OR = 0.96 were independent predictors of lacunar syndrome not due to lacunar infarct. Conclusions Although lacunar syndromes are highly suggestive of small deep cerebral infarctions, lacunar syndromes not due to lacunar infarcts are found in 16.6% of cases. The presence of sensorimotor stroke, limb weakness and sudden onset in a patient

  8. A robust protocol for regional evaluation of methacholine challenge in mouse models of allergic asthma using hyperpolarized 3He MRI.

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    Thomas, Abraham C; Potts, Erin N; Chen, Ben T; Slipetz, Deborah M; Foster, W Michael; Driehuys, Bastiaan

    2009-06-01

    Hyperpolarized (HP) (3)He magnetic resonance imaging has been recently used to produce high-resolution images of pulmonary ventilation after methacholine (MCh) challenge in mouse models of allergic inflammation. This capability presents an opportunity to gain new insights about these models and to more sensitively evaluate new drug treatments in the pre-clinical setting. In the current study, we present our initial experience using two-dimensional (2D), time-resolved (3)He MRI of MCh challenge-induced airways hyperreactivity (AHR) to compare ovalbumin-sensitized and challenged (N = 8) mice to controls (N = 8). Imaging demonstrated that ovalbumin-sensitized and challenged animals exhibited many large ventilation defects even prior to MCh challenge (four out of eight) compared to no defects in the control animals. Additionally, the ovalbumin-sensitized and challenged animals experienced a greater number of ventilation defects (4.5 +/- 0.4) following MCh infusion than did controls (3.3 +/- 0.6). However, due to variability in MCh delivery that was specific to the small animal MRI environment, the difference in mean defect number was not statistically significant. These findings are reviewed in detail and a comprehensive solution to the variability problem is presented that has greatly enhanced the magnitude and reproducibility of the MCh response. This has permitted us to develop a new imaging protocol consisting of a baseline 3D image, a time-resolved 2D series during MCh challenge, and a post-MCh 3D image that reveals persistent ventilation defects.

  9. Validity of apparent diffusion coefficient hyperpolarized 3He-MRI using MSCT and pulmonary function tests as references

    DEFF Research Database (Denmark)

    Diaz, Sandra; Casselbrant, Ingrid; Piitulainen, Eeva

    2008-01-01

    from MSCT. Both mean ADC and MSCT data were compared to PFT, especially percent of predicted diffusing capacity of carbon monoxide (%predicted DLCO), using Pearson's correlation test. RESULTS: Mean ADC and standard deviation values were 0.392+/-0.119 cm(2)/s for the established emphysema group and 0....... Correlations between mean ADC and EI and 15th percentile were both r=0.90 and for MLD r=0.59. There was higher correlation between mean ADC and %predicted DLCO (r=0.90) than between EI and %predicted DLCO (r=0.76). CONCLUSION: HP (3)He-MRI correlates well with density measurements from MSCT and agrees better...

  10. Analysis of acute ischemic stroke presenting classic lacunar syndrome. A study by diffusion-weighted MRI

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    Terai, Satoshi; Ota, Kazuki; Tamaki, Kinya [Hakujyuji Hospital, Fukuoka (Japan)

    2002-03-01

    We retrospectively assessed the pathophysiological features of acute ischemic stroke presenting ''classic'' lacunar syndrome by using diffusion-weighted imaging (DWI). Subjects were 16 patients who were admitted to our hospital within 24 hours of stroke onset and underwent DWI examination on admission. These were divided into three categorical groups; pure motor hemiplegia (PMH) in 8, sensorimotor stroke (SMS) in 7, and dysarthria-clumsy hand syndrome (DCHS) in 1. The fresh responsible lesions were identified by DWI in the perforating territory in 7 patients with PMH and 7 with SMS. Four (one had two possible response lesions; pons and corona radiata) and five patients in the respective groups were diagnosed as lacunar infarction on admission (the largest dimension of the lesion measuring smaller than 15 mm). On the contralateral side to the neurological symptoms, DWI revealed high intensities in cortex, subcortical white matter, and anterior and posterior border zones in the remaining one patient with PMH and in the precentral arterial region in one with DCHS. They were diagnosed as atherothrombotic infarction resulting from the occlusion of the internal carotid artery and cerebral embolism due to atrial fibrillation, respectively. Three patients with PMH showed progressive deterioration after admission and follow-up DWI study in an acute stage revealed enlargement of heir ischemic lesions. The present study suggests that DWI is a useful imaging technique for diagnosis of clinical categories and observation for pathophsiological alteration in the acute ischemic stroke patients with ''classic'' lacunar syndrome. Our results also indicate a necessity to be aware that various types of fresh ischemic lesions other than a single lacune might possibly be developing in cases with this syndrome. (author)

  11. A suggested generalization for the lacunarity index

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    Vernon-Carter, J.; Lobato-Calleros, C.; Escarela-Perez, R.; Rodriguez, E.; Alvarez-Ramirez, J.

    2009-10-01

    Nowadays, lacunarity is a well-accepted concept to complement fractality studies of complex sets. Lacunarity features are used to assess the largeness of gaps or holes of complex signals and images. As it stands, the lacunarity analysis used is an index averaging the behavior of small- and large-size structures in a given set. The aim of this work is to propose a generalized lacunarity concept on the basis of generalized moments. In this form, the lacunarity index, depending on a discrimination parameter, is oriented to quantify lacunarity associated with objects of different size. Textbook and real images are used to illustrate the ability of the generalized lacunarity index for displaying interesting features of real complex sets.

  12. Study of Local Mineralized Intensity Using Rescaled Range Analysis and Lacunarity Analysis

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    Li Wan

    2013-07-01

    Full Text Available In this paper, the gold grade series along drifts have been analyzed using two methods, rescaled range analysis and lacunarity analysis which are commonly used in nonlinear systems analysis. The aim of this study is to better understand the ore-forming processes and identify the local mineralized intensity and interactions that influence the spatial structure of gold element grade distribution, in the Dayingezhuang fault-controlled, disseminated-veinlet gold deposit in the Jiaodong gold province, eastern China. The result shows that the efficiency of two methods, in distinguishing between weakly mineralized, moderately mineralized and intensely mineralized of ore-forming area. It is obvious that the two parameters of both Hurst and lacunarity index in the weakly mineralized drifts are distinguished from those in the mineralized drifts, and the lower the index is, the more homogeneously distributed of the elements and the mineral intensity is relatively smaller. The methods used in this paper provide a relatively comprehensive description for local mineral intensity, offering an evidence for the identification of mineralization intensity and providing a guidance for further determination to the extent of deposit concentration and delineation of target mineralization zone.

  13. Clinical study on magnetic resonance imaging of lacunar infarcts and cerebrovascular high-risk group

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    Hironaka, Masatoshi (Hiroshima Univ. (Japan). School of Medicine)

    1990-04-01

    Magnetic resonance imaging (MRI) study was performed in 32 patients with recent lacunar stroke. T2-weighted images showed ischemic lesions more clearly than T1-weighted images. Sixty-six percent of 32 patients had periventricular lesions. Eighty-four percent had subcortical white matter lesions. Sixty-nine percent had lesions in basal ganglia. Twenty-eight percent had lesions in brainstem. Periventricular lesions were revealed symmetrically. On the other hand, lesions in other areas were not detected symmetrically. Severe periventricular lesions on MRI were similar to those of Binswanger's disease. Patients with severe periventricular lesions had often hypertension. Moreover, two of them had dementia. Twenty-three patients with transient ischemic attack had less remarkable lesions than patients with lacunar stroke. Thirty-seven patients with a history of cerebrovascular risk factors (hypertension, diabetes mellitus) had severer lesions compared with normal controls. Sixty-one percent of controls, who had no cerebrovascular symptoms and signs, had MRI lesions. These results suggest that MRI is useful for detection of cerebral ischemic lesions with no associated clinical symptoms or signs. (author).

  14. Osteocyte lacunar properties in rat cortical bone

    DEFF Research Database (Denmark)

    Bach-Gansmo, Fiona Linnea; Weaver, James C.; Jensen, Mads Hartmann;

    2015-01-01

    -species but also inter-site variation in lacunar properties. Here, osteocyte lacunae in rat cortical bone have been studied using synchrotron radiation micro computed tomography (SR μCT) and backscattered electron (BE) microscopy. Quantitative lacunar geometric characteristics are reported based on the synchrotron...

  15. Multifractal modelling and 3D lacunarity analysis

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    Hanen, Akkari, E-mail: bettaieb.hanen@topnet.t [Laboratoire de biophysique, TIM, Faculte de Medecine (Tunisia); Imen, Bhouri, E-mail: bhouri_imen@yahoo.f [Unite de recherche ondelettes et multifractals, Faculte des sciences (Tunisia); Asma, Ben Abdallah, E-mail: asma.babdallah@cristal.rnu.t [Laboratoire de biophysique, TIM, Faculte de Medecine (Tunisia); Patrick, Dubois, E-mail: pdubois@chru-lille.f [INSERM, U 703, Lille (France); Hedi, Bedoui Mohamed, E-mail: medhedi.bedoui@fmm.rnu.t [Laboratoire de biophysique, TIM, Faculte de Medecine (Tunisia)

    2009-09-28

    This study presents a comparative evaluation of lacunarity of 3D grey level models with different types of inhomogeneity. A new method based on the 'Relative Differential Box Counting' was developed to estimate the lacunarity features of grey level volumes. To validate our method, we generated a set of 3D grey level multifractal models with random, anisotropic and hierarchical properties. Our method gives a lacunarity measurement correlated with the theoretical one and allows a better model classification compared with a classical approach.

  16. Development and application of methods to quantify spatial and temporal hyperpolarized 3He MRI ventilation dynamics: preliminary results in chronic obstructive pulmonary disease

    Science.gov (United States)

    Kirby, Miranda; Wheatley, Andrew; McCormack, David G.; Parraga, Grace

    2010-03-01

    Hyperpolarized helium-3 (3He) magnetic resonance imaging (MRI) has emerged as a non-invasive research method for quantifying lung structural and functional changes, enabling direct visualization in vivo at high spatial and temporal resolution. Here we described the development of methods for quantifying ventilation dynamics in response to salbutamol in Chronic Obstructive Pulmonary Disease (COPD). Whole body 3.0 Tesla Excite 12.0 MRI system was used to obtain multi-slice coronal images acquired immediately after subjects inhaled hyperpolarized 3He gas. Ventilated volume (VV), ventilation defect volume (VDV) and thoracic cavity volume (TCV) were recorded following segmentation of 3He and 1H images respectively, and used to calculate percent ventilated volume (PVV) and ventilation defect percent (VDP). Manual segmentation and Otsu thresholding were significantly correlated for VV (r=.82, p=.001), VDV (r=.87 p=.0002), PVV (r=.85, p=.0005), and VDP (r=.85, p=.0005). The level of agreement between these segmentation methods was also evaluated using Bland-Altman analysis and this showed that manual segmentation was consistently higher for VV (Mean=.22 L, SD=.05) and consistently lower for VDV (Mean=-.13, SD=.05) measurements than Otsu thresholding. To automate the quantification of newly ventilated pixels (NVp) post-bronchodilator, we used translation, rotation, and scaling transformations to register pre-and post-salbutamol images. There was a significant correlation between NVp and VDV (r=-.94 p=.005) and between percent newly ventilated pixels (PNVp) and VDP (r=- .89, p=.02), but not for VV or PVV. Evaluation of 3He MRI ventilation dynamics using Otsu thresholding and landmark-based image registration provides a way to regionally quantify functional changes in COPD subjects after treatment with beta-agonist bronchodilators, a common COPD and asthma therapy.

  17. Fractal dimension and lacunarity analysis of mammographic patterns in assessing breast cancer risk related to HRT treated population: a longitudinal and cross-sectional study

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    Karemore, Gopal; Nielsen, Mads

    2009-02-01

    Structural texture measures are used to address the aspect of breast cancer risk assessment in screening mammograms. The current study investigates whether texture properties characterized by local Fractal Dimension (FD) and Lacunarity contribute to asses breast cancer risk. FD represents the complexity while the Lacunarity characterize the gappiness of a fractal. Our cross-sectional case-control study includes mammograms of 50 patients diagnosed with breast cancer in the subsequent 2-4 years and 50 matched controls. The longitudinal double blind placebo controlled HRT study includes 39 placebo and 36 HRT treated volunteers for two years. ROIs with same dimension (250*150 pixels) were created behind the nipple region on these radiographs. Box counting method was used to calculate the fractal dimension (FD) and the Lacunarity. Paired t-test and Pearson correlation coefficient were calculated. It was found that there were no differences between cancer and control group for FD (P=0.8) and Lacunarity (P=0.8) in crosssectional study whereas earlier published heterogeneity examination of radiographs (BC-HER) breast cancer risk score separated groups (p=0.002). In the longitudinal study, FD decreased significantly (Pbreast cancer risk, nor show good sensitivity to HRT.

  18. Lacunarity as a texture measure for a tropical forest landscape

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    Su, Haiping; Krummel, J.

    1996-01-01

    Fragmentation and loss of tropical forest cover alters terrestrial plant and animal population dynamics, reduces biodiversity and carbon storage capacity, and, as a global phenomenon could affect regional and global climate patterns. Lacunarity as a texture measure can offer a simple solution to characterize the texture of tropical forest landscape and determine spatial patterns associated with ecological processes. Lacunarity quantifies the deviation from translational invariance by describing the distribution of gaps within a binary image at multiple scales. As lacunarity increases, the spatial arrangement of tropical forest gaps will also increase. In this study, we used the Spatial Modeler in Imagine as a graphic programming tool to calculate lacunarity indices for a tropical forest landscape in Southern Mexico and Northern Guatemala. Lacunarity indices were derived from classified Landsat MSS images acquired in 1974 and 1984. Random-generated binary images were also used to derive lacunarity indices and compared with the lacunarity of forest patterns derived from the classified MSS images. Tropical forest area declined about 17%, with most of the forest areas converted into pasture/grassland for grazing. During this period, lacunarity increased about 25%. Results of this study suggest that tropical forest fragmentation could be quantified with lacunarity measures. The study also demonstrated that the Spatial Modeler can be useful as a programming tool to quantify spatial patterns of tropical forest landscape by using remotely sensed data.

  19. Correlative factors of cognitive impairment in patients with lacunar infarcts

    Institute of Scientific and Technical Information of China (English)

    Zhang Qiujuan; Yao Xiaoxin; Guo Youmin; Zhang Gejuan; Yang Junle

    2007-01-01

    Objective To study the relationships between cognitive impairment in patients with lacunar infarcts and quantitative CT measures and to determine the independent correlative factors of cognitive impairment. Methods Neuropsychological examination was conducted for 128 patients with acute lacunar infarct. Number, location, and volume of infarcts, cerebral atrophy index and severity of white matter lesions (WMLs) were measured and recorded. Results The number of lacunar infarcts in cognitive impairment (CI) group was significantly larger than that in cognitive normal (CN) group. Mean width of sulcus and sylvian fissure, index of frontal horn and ventricular-brain ratio (VBR) were significantly different in both groups. There were more patients with 3 grades or 4 grades WMLs in CI group (62%) than those in CN group (22%). The total volume of lacunar infarcts showed no statistically significant difference. Logistic regression analysis indicated that the number of lacunar infarcts in frontal subcortex and thalamus, the volume of infarcts in anterior periventricular white matter, width of cerebral sulcus and sylvian fissure were correlated with cognitive impairment respectively. Additionally, age and education were correlative factors of cognitive impairment in patients with lacunar infarct. Conclusion Correlative factors of cognitive impairment in patients with lacunar infarct are not merely one feature, but a combination of infarct features (number, location, and volume), cortical atrophy and host factors (age and education).

  20. Enlarged perivascular spaces and lacunar infarction Cerebral magnetic resonance evaluation

    Institute of Scientific and Technical Information of China (English)

    Weihong Yan; Jing Fang; Cuijuan Zhou

    2008-01-01

    BACKGROUND:Previous studies have demonstrated that enlarged perivascular spaces(EPVS)arg a result of microvaseular disease.To date,there age few reports about the relationship between EPVS and lacunar infarction.OBJECTIVE:To investigate whether EPVS is associated with lacunar infarction on the basis of cerebral magnetic resonance(MR)examination,clinical symptoms and signs,and past medical history of patients.DESIGN,TIME AND SETTING:Case contrast analysis was performed at the Department of Neurology,Shanghai Ninth People's Hospital from January 2007 to January 2008.PARTICIPANTS:Sixty-eight patients with lacunar infarction were admired to the Department of Neurology of Shanghai Ninth People's Hospital,including 37 cases with first-ever infarction,and 31 with infarction recurrence.In addition,53 healthy people were selected as controls.METHODS:All participants underwent past medical history investigation,nervous system examination.and cranial MR.The subjects were assessed using the JMW rating scale to identify the EPVS grade.MAIN OUTCOME MEASURES:EPVS scores of patients and controls;risk factors for cerebral vascular disease in patients with first-ever or recurrence of lacunar infarction.RESULTS:The EPVS grade from lacunar infarction patients was significantly higher than of the control group(P<0.05).The EPVS grade in patients with recurring lacunar infarction was significantly higher than in patients with first-ever infarction(P<0.05).In addition,hypertension incidence in patients with recurring lacunar infarction was significantly higher than in patients wim first-ever infarction (P<0.05).CONCLUSION:Results indicate that EPVS is related to the incidence of lacunar infarction.Earlier screening of EPVS.and the evaluation of EPVS severity,is of great importance to control the risk factors for cerebral vascular disease and to prevent lacunar infarction.

  1. Accumulation of MRI markers of cerebral small vessel disease is associated with decreased cognitive function. A study in first-ever lacunar stroke and hypertensive patients.

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    Marjolein eHuijts

    2013-11-01

    Full Text Available Background – White matter lesions (WMLs, asymptomatic lacunar infarcts, brain microbleeds (BMBs and enlarged perivascular spaces (EPVS have been identified as silent lesions due to cerebral small vessel disease (cSVD. All these markers have been individually linked to cognitive functioning, but are also strongly correlated with each other. The combined effect of these markers on cognitive function has never been studied and would possibly provide more useful information on the effect on cognitive function. Methods – Brain MRI and extensive neuropsychological assessment were performed in 189 patients at risk for cSVD (112 hypertensive patients and 77 first-ever lacunar stroke patients. We rated the presence of any asymptomatic lacunar infarct, extensive WMLs, any deep BMB, and moderate to extensive EPVS in the basal ganglia. The presence of each marker was summed to an ordinal score between 0 and 4. Associations with domains of cognitive function (memory, executive function, information processing speed and overall cognition were analyzed with correlation analyses. Results – Correlation analyses revealed significant associations between accumulating cSVD burden and decreased performance on all cognitive domains (all p≤.001. Results remained significant for information processing speed (r=-.181, p=.013 and overall cognition (r=-.178, p=.017, after correction for age and sex. Testing of trend using linear regression analyses revealed the same results. Discussion – We tested a new approach to capture total brain damage resulting from cSVD and found that accumulation of MRI burden of cSVD is associated with decreased performance on tests of information processing speed and overall cognition, implying that accumulating brain damage is accompanied by worse cognitive functioning.

  2. Lacunar strokes: a single institutional experience

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    Osama Shukir Muhammed Amin

    2013-08-01

    Full Text Available Abstract: Objective: Lacunar ischemic strokes comprise approximately 25% of all ischemic strokes. We compared the risk factors and clinical pattern of this type of stroke between males and females. Methods: This observational study involved 50 consecutive patients with their first-ever lacunar stroke and was conducted at the department of neurology of Sulaimaniya general teaching hospital, Iraq from December 1, 2010 to March 1, 2013. Patients’ risk factors, clinical presentation, and strokes’ patterns were noted and a comparison was made between males and females. Results: Males (64% outnumbered females (36% with a male to female ration of 1.7. The mean age of males was 63 years while it was 61 years in females. Although hypertension was more common in females than in males, diabetes and smoking were more common in the latter group; however, there were no statistically significant differences between the 2 genders in terms of hypertension (P-value <0.3 and diabetes (P-value < 0.07 while smoking was strongly associated with male gender (P-value<0.0001. Pure motor hemiparesis, ataxic hemiparesis, pure sensory stroke, and dysarthria-clumsy hand syndrome were more common in males; only senori-motor stroke revealed a statistically significant difference in favor males (P-value<0.0001; 95% CI -1.7 to 19.2. There was no statistically significant difference in terms of which side of the brain was infarcted between males and females (P-value<0.4. Conclusion: Males around the age of 63 years were the main target for these lacunar strokes. Cigarette smoking and sensorimotor strokes were significantly associated with male gender. [Cukurova Med J 2013; 38(4.000: 659-666

  3. Association of Notch3 single-nucleotide polymorphisms and lacunar infarctions in patients

    Science.gov (United States)

    LI, YING; LIU, NAN; CHEN, HUI; HUANG, YONGHUA; ZHANG, WEIWEI

    2016-01-01

    Cerebrovascular disease is a leading cause of morbidity and mortality worldwide, which is influenced by genetic and environmental factors. The aim of the present study was to examine the association between single-nucleotide polymorphisms (SNPs) in Notch3 exons 3–6 and lacunar infarction by comparing SNPs between control subjects and those with lacunar infarction. A single-center case-control study was conducted to investigate the association between Notch3 SNPs and risk of stroke. A total of 140 patients were included in the study, 30 of whom had no infarction (control) and 110 had lacunar infarction. Lacunar patients were divided into the ‘pure lacunar’ and ‘lacunar + leukoarasis’ groups based on brain imaging. All the patients were of Chinese Han ethnicity, and the male to female ratio was 84:56. Patient clinical histories included hypertension, diabetes mellitus (DM), hyperlipidemia, and heart disease were recorded. The Notch3 sequence was obtained from the National Centser for Biotechnology Information database. Notch3 was amplified by polymerase chain reaction from whole blood samples, and exons 3–6 were sequenced to identify SNPs. The result showed that there was no significant difference in the prevalence of hypertension, DM, hyperlipidemia, and heart disease between the control and lacunar infarction patients. Notabley, the age of the lacunar + leukoarasis patients was significantly higher than that of the control and pure lacunar patients (P<0.05). Eight SNPs were detected at low frequencies, and only rs3815388 and rs1043994 exhibited slightly higher frequencies. A χ2 test indicated that Notch3 SNPs, particularly rs1043994, were associated with lacunar infarction (P<0.05). In conclusion, the result of the present study have shown that Notch3 SNPs, particularly rs1043994, are associated with lacunar infarction. PMID:26889213

  4. Lacunarity analysis of spaceborne radar image texture for rock unit discrimination

    Science.gov (United States)

    Dong, Pinliang

    Fractal geometry has led to new understanding of many natural objects and phenomena. As a scale-dependent measure, lacunarity can be used to discriminate different textures that may not be differentiated by fractal dimension. Based on a differential box counting method and a gliding-box algorithm, a new lacunarity estimation method is developed for texture analysis of digital images, and a "Lacunarity Analysis" extension built for ArcView (ESRI) geographical information system software. To reveal the directional properties of textures, the directionality of lacunarity is also defined. The new lacunarity measure is evaluated through quantitative comparison with the Voss lacunarity, the binary lacunarity, the grey level cooccurrence matrix (GLCM) based texture measures (homogeneity, contrast, dissimilarity, entropy), the fractal dimension, and the min-max operator using Brodatz textures. The results from Brodatz textures suggest that the new lacunarity estimation method for grey-scale images provides more accurate texture measurements than the above-mentioned fractal-based and statistical texture measures. In comparison with the Voss lacunarity, the fractal dimension, and the GLCM-based texture measures, the new lacunarity measure is then applied to dual-band (L and C) and dual-polarization (HH and HV) Shuttle Imaging Radar (SIR-C), and C-band HH polarization Radarsat images of two imaging modes for rock unit discrimination in a study area between California and Arizona, USA. Using textural analysis of 36 SIR-C and Radarsat sub-images and classification accuracy assessment of the combined Landsat Thematic Mapper (TM) images and spaceborne radar textural feature images, it has been demonstrated that the new lacunarity measure outperformed other texture measures in comparison, and the L-band HH polarization SIR-C image provides more textural information of the rock units compared with the Radarsat and other SIR-C radar images used in this study. The study shows that

  5. The correlation between cognitive function and cerebral white matter lesions/insulin resistance in patients with lacunar infarction:a clinical study of 184 cases

    Institute of Scientific and Technical Information of China (English)

    张琼予

    2013-01-01

    Objective To investigate the correlation between cognitive function and cerebral white matter lesions(WML)/insulin resistance(IR) in patients with stroke.Methods Between May 2011 and October 2011,the clin-ical data of 184 in-patients with lacunar infarction were

  6. Lacunar infarction:a hemodynamic analysis of 102 cases

    Institute of Scientific and Technical Information of China (English)

    张春玲

    2006-01-01

    Objective To study cerebrovascular lesion and lacunar infarction (LI) and to explore the pathogenesis of LI based on neuroradiological imaging. Methods Brain MRI,CT angiography (CTA) and CT perfusion (CTP) were performed in all 102 patients with LI. Results MRI showed single LI in 3 cases, multiple LI in 99 cases. CTA showed severe stenosis or occlusion of internal

  7. Alterations of mass density and 3D osteocyte lacunar properties in bisphosphonate-related osteonecrotic human jaw bone, a synchrotron µCT study.

    Directory of Open Access Journals (Sweden)

    Bernhard Hesse

    Full Text Available Osteonecrosis of the jaw, in association with bisphosphonates (BRONJ used for treating osteoporosis or cancer, is a severe and most often irreversible side effect whose underlying pathophysiological mechanisms remain largely unknown. Osteocytes are involved in bone remodeling and mineralization where they orchestrate the delicate equilibrium between osteoclast and osteoblast activity and through the active process called osteocytic osteolysis. Here, we hypothesized that (i changes of the mineralized tissue matrix play a substantial role in the pathogenesis of BRONJ, and (ii the osteocyte lacunar morphology is altered in BRONJ. Synchrotron µCT with phase contrast is an appropriate tool for assessing both the 3D morphology of the osteocyte lacunae and the bone matrix mass density. Here, we used this technique to investigate the mass density distribution and 3D osteocyte lacunar properties at the sub-micrometer scale in human bone samples from the jaw, femur and tibia. First, we compared healthy human jaw bone to human tibia and femur in order to assess the specific differences and address potential explanations of why the jaw bone is exclusively targeted by the necrosis as a side effect of BP treatment. Second, we investigated the differences between BRONJ and control jaw bone samples to detect potential differences which could aid an improved understanding of the course of BRONJ. We found that the apparent mass density of jaw bone was significantly smaller compared to that of tibia, consistent with a higher bone turnover in the jaw bone. The variance of the lacunar volume distribution was significantly different depending on the anatomical site. The comparison between BRONJ and control jaw specimens revealed no significant increase in mineralization after BP. We found a significant decrease in osteocyte-lacunar density in the BRONJ group compared to the control jaw. Interestingly, the osteocyte-lacunar volume distribution was not altered after

  8. Risk Factors for Silent Lacunar Infarction in Patients with Transient Ischemic Attack

    Science.gov (United States)

    Li, Ying; Liu, Nan; Huang, Yonghua; Wei, Wei; Chen, Fei; Zhang, Weiwei

    2016-01-01

    Background Lacunar infarctions represent 25% of ischemic strokes. Lacunar stroke and transient ischemic attack (TIA) share a number of symptoms. This study aimed to assess the potential risk factors for lacunar infarction in patients with TIA. Material/Methods This was a retrospective study performed at the Beijing Military General Hospital in patients with TIA admitted between March 2010 and December 2011. Patients were grouped according to lacunar vs. no lacunar infarction. All patients were diagnosed using diffusion-weighted imaging (DWI) on brain magnetic resonance imaging (MRI). Brain angiography (computed tomography and MRI) was used to measure intracranial stenosis. Carotid artery stenosis was measured by ultrasound. Results Patients with TIA and lacunar infarction (n=298) were older than those without lacunar infarction (n=157) (69.4±10.0 vs. 58.9±9.0 years, P<0.001) and showed a higher frequency of males (51.7% vs. 41.4%, P=0.037), hypertension (75.3% vs. 45.9%, P<0.001), diabetes (32.6% vs. 21.0%, P=0.010), hyperlipidemia (53.4% vs. 29.3%, P<0.001), carotid stenosis (73.2% vs. 40.1%, P<0.001), and intracranial stenosis (55.6% vs. 31.9%, P<0.001), but a lower frequency of alcohol drinking (8.1% vs. 14.0%, P=0.045). Lacunar infarction mostly involved the anterior circulation (62.8%). Multivariate analysis showed that age (odds ratio (OR)=1.085, 95% confidence interval (95%CI): 1.054–1.117, P<0.001), hypertension (OR=1.738, 95%CI: 1.041–2.903, P=0.035), hyperlipidemia (OR=2.169, 95%CI: 1.307–3.601, P=0.003), and carotid stenosis (OR=1.878, 95%CI: 1.099–3.206, P=0.021) were independently associated with lacunar infarction. Conclusions Age, hypertension, hyperlipidemia, and carotid stenosis were independently associated with silent lacunar infarction in patients with TIA. PMID:26864634

  9. Fractal analysis: fractal dimension and lacunarity from MR images for differentiating the grades of glioma.

    Science.gov (United States)

    Smitha, K A; Gupta, A K; Jayasree, R S

    2015-09-07

    Glioma, the heterogeneous tumors originating from glial cells, generally exhibit varied grades and are difficult to differentiate using conventional MR imaging techniques. When this differentiation is crucial in the disease prognosis and treatment, even the advanced MR imaging techniques fail to provide a higher discriminative power for the differentiation of malignant tumor from benign ones. A powerful image processing technique applied to the imaging techniques is expected to provide a better differentiation. The present study focuses on the fractal analysis of fluid attenuation inversion recovery MR images, for the differentiation of glioma. For this, we have considered the most important parameters of fractal analysis, fractal dimension and lacunarity. While fractal analysis assesses the malignancy and complexity of a fractal object, lacunarity gives an indication on the empty space and the degree of inhomogeneity in the fractal objects. Box counting method with the preprocessing steps namely binarization, dilation and outlining was used to obtain the fractal dimension and lacunarity in glioma. Statistical analysis such as one-way analysis of variance and receiver operating characteristic (ROC) curve analysis helped to compare the mean and to find discriminative sensitivity of the results. It was found that the lacunarity of low and high grade gliomas vary significantly. ROC curve analysis between low and high grade glioma for fractal dimension and lacunarity yielded 70.3% sensitivity and 66.7% specificity and 70.3% sensitivity and 88.9% specificity, respectively. The study observes that fractal dimension and lacunarity increases with an increase in the grade of glioma and lacunarity is helpful in identifying most malignant grades.

  10. Tunneling in quantum superlattices with variable lacunarity

    Energy Technology Data Exchange (ETDEWEB)

    Villatoro, Francisco R. [Departamento de Lenguajes y Ciencias de la Computacion, Universidad de Malaga, E-29071 Malaga (Spain); Monsoriu, Juan A. [Departamento de Fisica Aplicada, Universidad Politecnica de Valencia, E-46022 Valencia (Spain)], E-mail: jmonsori@fis.upv.es

    2008-05-19

    Fractal superlattices are composite, aperiodic structures comprised of alternating layers of two semiconductors following the rules of a fractal set. The scattering properties of polyadic Cantor fractal superlattices with variable lacunarity are determined. The reflection coefficient as a function of the particle energy and the lacunarity parameter present tunneling curves, which may be classified as vertical, arc, and striation nulls. Approximate analytical formulae for such curves are derived using the transfer matrix method. Comparison with numerical results shows good accuracy. The new results may be useful in the development of band-pass energy filters for electrons, semiconductor solar cells, and solid-state radiation sources up to THz frequencies.

  11. Correlation Study of Lacunar Infarction with Leukoaraiosis and Diabetes%伴腔隙性脑梗死的脑白质疏松症与糖尿病的相关性

    Institute of Scientific and Technical Information of China (English)

    陈瑾; 王丽娟; 刘欣; 王红霞

    2016-01-01

    Objective:To investigate the correlation study of lacunar infarction with leukoaraiosis and diabetes.Method:A total of 200 patients who admitted in the Department of Neurology,our hospital form August 2013 to August 2015 were divided into leukoaraiosis with diabetes group(the experiment group,n=100) and leukoaraiosis with-no diabetes group(the control group,n=100) according to their cerebral MRI findings and glucose levels.Result:The severity levels of leukoaraiosis in the experiment group more exceed than that of the control group(P<0.001).The grade of leukoaraiosis by Fazekas had a positive correlation with high blood sugar levels in diabtes patients.Conclusion:Leukoaraiosis is associated with diabets inpatients with lacunar infarction.%目的:研究伴腔隙性脑梗死患者脑白质疏松症的严重程度与糖尿病的相关性。方法:选择2013年8月-2015年8月在本院神经内科住院患者,经头颅核磁确诊为腔隙性脑梗死合并脑白质疏松患者200例为研究对象,伴腔隙性脑梗死的脑白质疏松症合并糖尿病患者为试验组,伴腔隙性脑梗死的脑白质疏松症非糖尿病患者为对照组,研究两组脑白质疏松的严重程度与糖尿病的相关性。结果:试验组的白质疏松严重程度明显高于对照组,差异有统计学意义(P<0.001)。脑白质疏松Fazekas评分分值与糖尿病患者血糖升高呈正相关。结论:伴腔隙性脑梗死的脑白质疏松的发生与糖尿病有一定相关性。

  12. An interactive mapping tool for visualizing lacunarity of laser scanned point clouds

    Science.gov (United States)

    Kania, Adam; Székely, Balázs

    2016-04-01

    Lacunarity, a measure of the spatial distribution of the empty space in a certain model or real space over large spatial scales, is found to be a useful descriptive quantity in many fields using imagery, including, among others, geology, dentistry, neurology. Its application in ecology was suggested more than 20 years ago. The main problem of its application was the lack of appropriate high resolution data. Nowadays, full-waveform laser scanning, also known as FWF LiDAR, provides the tool for mapping the vegetation in unprecedented details and accuracy. Consequently, the lacunarity concept can be revitalized, in order to study the structure of the vegetation in this sense as well. Calculation of lacunarity, even if it is done in two dimensions (2D), is still has its problems: on one hand it is a number-crunching procedure, on the other hand, it produces 4D results: at each 3D point it returns a set of data that are function of scale. These data sets are difficult to visualize, to evaluate, and to compare. In order to solve this problem, an interactive mapping tool has been conceptualized that is designed to manipulate and visualize the data, lets the user set parameters for best visualization or comparison results. The system is able to load large amounts of data, visualize them as lacunarity curves, or map view as horizontal slices or in 3D point clouds coloured according to the user's choice. Lacunarity maps are presented as a series of (usually) horizontal profiles, e.g. rasters, which cells contain color-mapped values of selected lacunarity of the point cloud. As lacunarity is usually analysed in a series of successive windows sizes, the tool can show a series of rasters with sequentially animated lacunarity maps calculated for various window sizes. A very fast switching of colour schemes is possible to facilitate rapid visual feedback to better understand underlying data patterns exposed by lacunarity functions. In the comparison mode, two sites (or two areas

  13. Correlative factors of cognitive impairment in patients with lacunar infarcts

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Patients with lacunar infarcts are thought tohave an increased risk of cognitive i mpair ment anddementia[1].Cognitive i mpair ment is a predictor ofpoor functional outcome in stroke survivors[2].However,in patients with lacunar infarcts,thepathway leading to cognitive i mpair ment is notclear.According to the lacunar hypothesis,cogni-tive i mpair ment results fromincreased number andvolume of lacunes,especially whenlocated strategi-cally within frontal subcortical loops[3];while Feinet al[4]found that cogn...

  14. A lacunarity-based approach to evaluate Martian surfaces

    Science.gov (United States)

    Székely, Balázs; Kania, Adam; Magyar, Zoltán

    2016-04-01

    Terrestrial planets show great variety in terms of geomorphological patterns: the surface is shaped on one hand by the various phases of asteroid bombardment, on the other hand internal and external processes create or have created landform elements at various scales. This richness in forms have already been considered in terms of fractal or multifractal analyses, resulting in various considerations. However, so far the counterpart of the fractal analysis, the lacunarity analysis has been seldom carried out. Lacunarity, a measure of the spatial distribution of the empty space in a certain model or real space over large spatial scales, is found to be a useful descriptive quantity in many fields using imagery. Lacunarity can be calculated in various dimensions; in most of the cases 2D calculation is performed. Our project also aims at calculating 2D lacunarity curves, however, we also use digital terrain models (DTMs) of the planet Mars, introducing partly the third dimension into the calculation. DTMs are converted to horizontal slices of the topography and these slices are then treated as images. The lacunarity analysis is performed on these stacks of images resulting in large amount of lacunarity curves. These curves can be compared locally or regionally, and the set of curves can be used for more global comparisons. Our preliminary results show that characteristic differences can be detected between various Martian surface types, i.e. the lacunarity results, similar to fractal dimensions, have a certain descriptive power. As this type of lacunarity analysis provide larger amount of descriptors (multiple lacunarity functions) than the fractal dimension values and the scale of analysis (area of interest taken into account in the computing) can be selected according to the needs, it seems to be possible to create lacunarity libraries for general use. In this preliminary phase of the project tools and techniques are tested to compare effectively the resulting

  15. Prospective study of disturbance of intelligence of patients with lacunar stroke%腔隙性脑梗死患者智能障碍的前瞻性研究

    Institute of Scientific and Technical Information of China (English)

    陈湛愔; 陈逢俭; 梁秀竹

    2003-01-01

    Aim To find the regularity of disturbance of intelligence through prospective study of patients with lacunar stroke.Methods 186 patients with lacunar stroke recruited in Department of Neurology of Affiliated Central Hospital of Guangdong Medical College entered this study,51 cases were combined with slight aphemia and most of them achieved obvious improvement within one week after hopitalization,and aphasis was not seen in others.The symptoms of limb paralysis of all the patients were slight and the muscular strengths were all above grade IV,which were improved obviously within one week.Then all the 186 cases were measured with adult intelligence table and multiple correlation analysis was done according to sex,age,job and education extent of patients and image characteristics.Results The intelligence of 130 patients with lacunar stroke was lower than normal and accounted for 70% of 186 cases.51 cases belonged to severe disturbance of intelligence(VIQ< 69) and accounted for 27.4% .The relationship between education extent and disturbance of intelligence presented significant negative correlation(r=-0.6307,P=0.001).The cerebral infarction in left - side basal ganglion,area of corona radiata and left - side temporal lobe could easily cause disturbance of intelligence(r=-0.217,P=0.003) than right side.Binswanger syndrome was the important reason leading to disturbance of intelligence(r=-0.2677,P< 0.001).Conclusion Different lesion locus often leads to obviously different extent of disturbance of intelligence.Left hemisphere lesion could easily cause disturbance of intelligence,especially left basal ganglion and temporal lobe.The disturbance of intelligence of patients with multiple locus is severer than that with single locus.In addition,single infracortical cava stroke can cause obvious disturbance of intelligence.The disturbance of intelligence caused by sex,age and job has no correlation with that caused by infracortical cava stroke,but it presents negative

  16. Lacunarity Measures of Potential Fields in Covered Lithology Identification

    Science.gov (United States)

    Gettings, M. E.

    2013-12-01

    Measure distributions, both multifractal and other kinds, are not unique, so spatial patterns with the same measure may have different appearances. Lacunarity analysis is a method of description of dispersion in spatial patterns across a range of scales, and is one way of descriminating clustering of similar values. Lacunarity of an image was calculated using a moving window across a range of scales as the ratio of the second moment divided by the square of the first moment for values within the window. This gives a curve of lacunarity versus resolution (scale); the curve is concave for highly clustered data, pseudolinear or convex for data with clusters at many scales such as multifractal simulations, and constant for uniformly spaced data. Breaks in slope of the curve indicate scales that are important in the structure of the spatial pattern. Gravity and magnetic field anomaly data are well known to be multifractal and thus calculated lacunarities of gridded datasets have been investigated to determine if the resulting curves are a useful measure of texture of the potential field data and helpful in identifying likely lithologies at depth beneath cover. Lacunarity is often calculated on binary data, but it can also be calculated using quantitative data. The quantitative data case lacunarity measure was computed for grids using a 25 by 25 km window moving over the grid, each window overlapping the previous one by 12.5 km. The data were the aeromagnetic and isostatic gravity anomaly grids for the state of Arizona at 0.5 km grid-interval, resulting in a lacunarity curves for gravity and aeromagnetic anomaly for each of approximately 2500 windows. The open-source software R was used for plotting a map of window center locations and lacunarity curves, and the map was loaded into Google Earth, together with maps of the gravity and magnetic field anomaly, porphyry copper deposit locations, and the geological map of Arizona. Windows were selected to compare lacunarity

  17. MRI findings in patients with multiple lacunar infarcts manifesting hyperactive-type delirium

    Energy Technology Data Exchange (ETDEWEB)

    Arahata, Yutaka; Motegi, Yoshimasa; Furuse, Masahiro (Nakatsugawa Municipal General Hospital, Gifu (Japan)); Watanabe, Masaki; Takahashi, Akira

    1994-04-01

    MRI studies were carried out on 69 patients with multiple lacunar infarcts: 32 had hyperactive-type delirium and the other 37 were non-delirious controls. Between the two groups, there were no statistically significant differences in mean age and sex distribution. In the corona radiata and basal ganglia, the number of infarcts did not differ between the two groups. However, the extent of thalamic infarcts and periventricular hyperintensity (PVH), the maximal width of the third ventricle and Evans' ratio among the delirious patients were significantly larger than those in the controls. In conclusion, thalamic lesions and diffuse advanced PVH may have an intimate correlation in the development of hyperactive-type delirium in patients with multiple lacunar infarcts. (author).

  18. Biomaterial porosity determined by fractal dimensions, succolarity and lacunarity on microcomputed tomographic images

    Energy Technology Data Exchange (ETDEWEB)

    N' Diaye, Mambaye [LUNAM Université, GEROM Groupe Etudes Remodelage Osseux et bioMatériaux-LHEA, IRIS-IBS Institut de Biologie en Santé, CHU d' Angers, 49933 ANGERS Cedex (France); Degeratu, Cristinel [LUNAM Université, GEROM Groupe Etudes Remodelage Osseux et bioMatériaux-LHEA, IRIS-IBS Institut de Biologie en Santé, CHU d' Angers, 49933 ANGERS Cedex (France); University Politehnica of Bucharest, Faculty of Applied Chemistry and Materials Science, Department of Bioresources and Polymer Science, Calea Victoriei 149, 010072, Sector 1, Bucharest (Romania); Bouler, Jean-Michel [Inserm UMR 791, LIOAD, University of Nantes, 44000 Nantes (France); Chappard, Daniel, E-mail: daniel.chappard@univ-angers.fr [LUNAM Université, GEROM Groupe Etudes Remodelage Osseux et bioMatériaux-LHEA, IRIS-IBS Institut de Biologie en Santé, CHU d' Angers, 49933 ANGERS Cedex (France)

    2013-05-01

    Porous structures are becoming more and more important in biology and material science because they help in reducing the density of the grafted material. For biomaterials, porosity also increases the accessibility of cells and vessels inside the grafted area. However, descriptors of porosity are scanty. We have used a series of biomaterials with different types of porosity (created by various porogens: fibers, beads …). Blocks were studied by microcomputed tomography for the measurement of 3D porosity. 2D sections were re-sliced to analyze the microarchitecture of the pores and were transferred to image analysis programs: star volumes, interconnectivity index, Minkowski–Bouligand and Kolmogorov fractal dimensions were determined. Lacunarity and succolarity, two recently described fractal dimensions, were also computed. These parameters provided a precise description of porosity and pores' characteristics. Non-linear relationships were found between several descriptors e.g. succolarity and star volume of the material. A linear correlation was found between lacunarity and succolarity. These techniques appear suitable in the study of biomaterials usable as bone substitutes. Highlights: ► Interconnected porosity is important in the development of bone substitutes. ► Porosity was evaluated by 2D and 3D morphometry on microCT images. ► Euclidean and fractal descriptors measure interconnectivity on 2D microCT images. ► Lacunarity and succolarity were evaluated on a series of porous biomaterials.

  19. 维生素B12与腔隙性梗死后抑郁的相关性分析%Study on the association of Vitamin B12 and depression secondary to lacunar cerebral infarction

    Institute of Scientific and Technical Information of China (English)

    唐劭年; 任兰振; 胡宗继; 刘立雄

    2014-01-01

    目的:对维生素B12与腔隙性梗死后抑郁存在的相关性进行探讨。方法将我院2011-01-2013-01收治的腔隙性梗死患者798例分为对照组708例与观察组90例,对照组无抑郁症,观察组存在抑郁症(根据汉密尔顿抑郁量表判定),对比并分析2组患者的维生素B12水平。结果对照组血清维生素B12平均浓度为(178.6±20.7)pmol/L ,维生素B12缺乏197例(27.9%),观察组,血清维生素 B12平均浓度(141.7±19.7)pmol/L ,维生素 B12缺乏60例(66.7%),2组比较差异均有统计学意义( P<0.05)。结论维生素B12缺乏与腔隙性梗死后抑郁存在着相关性,腔隙性梗死并抑郁患者的维生素B12水平较普通腔隙性梗死患者更低,维生素B12缺乏情况较为明显,在治疗过程中适当补充维生素B12可以让患者的抑郁症状得到缓解,并可提升腔隙性梗死的治疗效果,促进患者恢复。%Objective To investigate the relevance between vitamin B12 and depression after lacunar cerebral infarc-tion.Methods Seventy hundred and ninety-eight patients with lacunar cerebral infarction admitted to our hospital from January 2011 to January 2011 were divided into control group(708 cases) and observation group (90 cases) ,no depression in control group patients ,the observation group patients had depression (judged according to the Hamilton depression rating scale ) ,vita-min B12 levels of patients in the two groups were analyzed and compared.Results The mean concentration of serum vitamin B12 of the control group was(178.6 ± 20.7)pmol/L ,the number of patients with vitamin B12 deficiency was 197 ,the ratio of which was 27.9% ;In the observation group ,the mean concentration of serum vitamin B12 was(141.7 ± 19.7)pmol/L ,the number of patients with vitamin B12 deficiency was 60 ,the ratio of which was 66.7%.The difference between the two groups had statisti-cal significance (P<0.05). Conclusion There is

  20. Location of lacunar infarcts correlates with cognition in a sample of non-disabled subjects with age-related white-matter changes: the LADIS study

    DEFF Research Database (Denmark)

    Benisty, S; Gouw, A A; Porcher, R

    2009-01-01

    OBJECTIVES: In cerebral small vessel disease, white-matter hyperintensities (WMH) and lacunes are both related to cognition. Still, their respective contribution in older people remains unclear. The purpose of this study is to assess the topographic distribution of lacunes and determine whether i...... and caudate nucleus. CONCLUSION: In non-disabled elderly subjects with leucoaraisosis, the location of lacunes within subcortical grey matter is a determinant of cognitive impairment, independently of the extent of WMH.......OBJECTIVES: In cerebral small vessel disease, white-matter hyperintensities (WMH) and lacunes are both related to cognition. Still, their respective contribution in older people remains unclear. The purpose of this study is to assess the topographic distribution of lacunes and determine whether...... it has an impact on cognitive functions in a sample of non-disabled patients with age-related white-matter changes. METHODS: Data were drawn from the baseline evaluation of the LADIS (Leucoaraioisis and Disability study) cohort of non-disabled subjects beyond 65 years of age. The neuropsychological...

  1. Preliminary analysis of osteocyte lacunar density in long bones of tetrapods: all measures are bigger in sauropod dinosaurs.

    Directory of Open Access Journals (Sweden)

    Koen W H Stein

    Full Text Available Osteocytes harbour much potential for paleobiological studies. Synchrotron radiation and spectroscopic analyses are providing fascinating data on osteocyte density, size and orientation in fossil taxa. However, such studies may be costly and time consuming. Here we describe an uncomplicated and inexpensive method to measure osteocyte lacunar densities in bone thin sections. We report on cell lacunar densities in the long bones of various extant and extinct tetrapods, with a focus on sauropodomorph dinosaurs, and how lacunar densities can help us understand bone formation rates in the iconic sauropod dinosaurs. Ordinary least square and phylogenetic generalized least square regressions suggest that sauropodomorphs have lacunar densities higher than scaled up or comparably sized mammals. We also found normal mammalian-like osteocyte densities for the extinct bovid Myotragus, questioning its crocodilian-like physiology. When accounting for body mass effects and phylogeny, growth rates are a main factor determining the density of the lacunocanalicular network. However, functional aspects most likely play an important role as well. Observed differences in cell strategies between mammals and dinosaurs likely illustrate the convergent nature of fast growing bone tissues in these groups.

  2. Preliminary analysis of osteocyte lacunar density in long bones of tetrapods: all measures are bigger in sauropod dinosaurs.

    Science.gov (United States)

    Stein, Koen W H; Werner, Jan

    2013-01-01

    Osteocytes harbour much potential for paleobiological studies. Synchrotron radiation and spectroscopic analyses are providing fascinating data on osteocyte density, size and orientation in fossil taxa. However, such studies may be costly and time consuming. Here we describe an uncomplicated and inexpensive method to measure osteocyte lacunar densities in bone thin sections. We report on cell lacunar densities in the long bones of various extant and extinct tetrapods, with a focus on sauropodomorph dinosaurs, and how lacunar densities can help us understand bone formation rates in the iconic sauropod dinosaurs. Ordinary least square and phylogenetic generalized least square regressions suggest that sauropodomorphs have lacunar densities higher than scaled up or comparably sized mammals. We also found normal mammalian-like osteocyte densities for the extinct bovid Myotragus, questioning its crocodilian-like physiology. When accounting for body mass effects and phylogeny, growth rates are a main factor determining the density of the lacunocanalicular network. However, functional aspects most likely play an important role as well. Observed differences in cell strategies between mammals and dinosaurs likely illustrate the convergent nature of fast growing bone tissues in these groups.

  3. Parsimonious classification of binary lacunarity data computed from food surface images using kernel principal component analysis and artificial neural networks.

    Science.gov (United States)

    Iqbal, Abdullah; Valous, Nektarios A; Sun, Da-Wen; Allen, Paul

    2011-02-01

    Lacunarity is about quantifying the degree of spatial heterogeneity in the visual texture of imagery through the identification of the relationships between patterns and their spatial configurations in a two-dimensional setting. The computed lacunarity data can designate a mathematical index of spatial heterogeneity, therefore the corresponding feature vectors should possess the necessary inter-class statistical properties that would enable them to be used for pattern recognition purposes. The objectives of this study is to construct a supervised parsimonious classification model of binary lacunarity data-computed by Valous et al. (2009)-from pork ham slice surface images, with the aid of kernel principal component analysis (KPCA) and artificial neural networks (ANNs), using a portion of informative salient features. At first, the dimension of the initial space (510 features) was reduced by 90% in order to avoid any noise effects in the subsequent classification. Then, using KPCA, the first nineteen kernel principal components (99.04% of total variance) were extracted from the reduced feature space, and were used as input in the ANN. An adaptive feedforward multilayer perceptron (MLP) classifier was employed to obtain a suitable mapping from the input dataset. The correct classification percentages for the training, test and validation sets were 86.7%, 86.7%, and 85.0%, respectively. The results confirm that the classification performance was satisfactory. The binary lacunarity spatial metric captured relevant information that provided a good level of differentiation among pork ham slice images.

  4. Hemodynamic factors may play a critical role in neurological deterioration occurring within 72 hrs after lacunar stroke.

    Directory of Open Access Journals (Sweden)

    Yen-Chu Huang

    Full Text Available BACKGROUND: Whether a perfusion defect exists in lacunar infarct and whether it is related to early neurological deterioration (END is still under debate. The aim of this study was to evaluate whether END in lacunar infarct is related to a perfusion defect using diffusion-weighted imaging (DWI, diffusion tensor imaging (DTI and perfusion MR imaging. METHODS: One hundred and forty-one consecutive patients had an MRI scan within 30 hours after onset of symptoms and 43 patients with acute lacunar infarct and classic lacunar syndrome were recruited. The MRI sequences included DWI, DTI and cerebral blood flow (CBF maps to respectively represent the topographic locations of acute infarcts, the corticospinal tract and perfusion defects. The END was defined in reference to the National Institute of Health Stroke Scale (NIHSS as an increase ≧2 within 72 hours. Cohen's Kappa coefficient was used to examine the reliability between the 2 image readers. A multivariate logistic regression model was constructed adjusting for baseline variables. RESULTS: Ten out of the 43 patients had END. Patients having END was significantly associated with lower chances of favorable and good outcomes at 3 months (p = 0.01 and p = 0.002, respectively. END was predicted when the non-core hypoperfused area overlapped on the corticospinal tract, which is defined as the expected END profile. Cohen's Kappa coefficient between the 2 image readers to define images of expected END profiles was 0.74. In 15 patients with expected END profile, 9 had END clinically, whereas 28 patients had no expected END profile, and only 1 patient had END (p<0.0001. After adjusting for sex, the expected END profile was still associated with END (odds ratio, 42.2; p = 0.002. CONCLUSION: Our study demonstrated that the END in acute lacunar stroke is likely related to the transformation of non-core hypoperfused area into infarction in the anatomy of corticospinal tracts.

  5. 腔隙性脑梗死患者脑微出血与血清同型半胱氨酸的相关性研究%The Study of Cerebral Microbleeds and Homocysteine in Lacunar Infarction

    Institute of Scientific and Technical Information of China (English)

    张金; 郝冬琳; 何国平

    2014-01-01

    目的:分析腔隙性脑梗死患者脑微出血(CMB)与血清同型半胱氨酸(Hcy)的关系。方法选择急性腔隙性脑梗死患者85例,行MR SWI序列检查,根据CMB的数量,分为轻度(1个CMB)、中度(4个CMB)、重度CMB(10个以上CMB)组。记录患者临床特点,检测患者血清Hcy水平,分析Hcy与CMB的关系。结果85例急性腔隙性脑梗死患者中,有CMB 35例(41.2%),其中轻度CMB组5例、中度CMB组10例、重度CMB组20例。血清同型半胱氨酸:CMB轻度组(14.2±3.1)μmol·L-1,中度组(17.5±2.6)μmol·L-1,重度组(19.0±3.8)μmol·L-1,方差分析发现,组间比较差异有统计学意义(F=4.579,P=0.019);CMB重度组血清Hcy水平高于轻度及中度组(P<0.05);Spearm相关分析发现CMB病变程度与血清Hcy水平呈正相关(r=0.768,P<0.001)。结论血清Hcy与腔隙性脑梗死患者的CMB有关,Hcy是CMB可能的危险因素;Hcy可以作为脑小血管病损伤的标志物之一,对CMB诊断和治疗有重要意义。%Aim To investigate the associations between the presence of cerebral microbleeds (CMB) and homocysteine (Hcy) in lacunar infarction. Methods Eighty five lacunar infarction patients were enrolled. All patients received cranial magnetic resonance imaging included susceptibility-weighted imaging at the ifrst week. The serum levels of Hcy were detected in patients. Results Among a total of 85 patients, 35(41.2%) patients were detected with CMB. The Hcy levels were (14.2±3.1) μmol·L-1 in mild CMB group, (17.5±2.6)μmol·L-1 in moderate CMB group, (19.0±3.8)μmol·L-1 in severe CMB group, and there were signiifcant differences by analysis of variance (F=4.579,P=0.019). The Hcy levels in severe CMB group were higher than that of mild and moderate CMB group (P<0.05). Spearm analysis indicated that the severity of CMB was positively related with Hcy levels (r=0.768, P<0.001). Conclusion CMB have a relatively high prevalence in lacunar infarction. Hcy is

  6. Lacunarity of geophysical well logs in the Cantarell oil field, Gulf of Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Arizabalo, Ruben Dario [Instituto Mexicano del Petroleo, Mexico, D.F. (Mexico); Oleschko, Klavdia [Centro de Geociencias, Universidad Nacional Autonoma de Mexico, Juriquilla, Queretaro (Mexico); Korvin, Gabor [King Fahd University, Dhahran (Saudi Arabia); Lozada, Manuel [Instituto Mexicano del Petroleo, Mexico, D.F. (Mexico); Castrejon, Ricardo [Facultad de Ingenieria, Universidad Nacional Autonoma de Mexico, Mexico, D.F. (Mexico); Ronquillo, Gerardo [Instituto Mexicano del Petroleo, Mexico, D.F. (Mexico)

    2006-04-15

    Lacunarity and fractal variations in geophysical well logs are associated with stratigraphic and petrophysical properties of the naturally fractured Cantarell field in the Gulf of Mexico. Neutron porosity (NPHI), density (RHOB, DRHO, PEF), resistivity (LLD, LLS, MSFL), natural radioactivity (GR, CGR, URAN, POTA, THOR) and caliper (CALI) logs are studied. The resistivity logs yielded remarkably high lacunarity values, especially in the hydrocarbon source- and reservoir rocks. Lacunarity {delta} was found to depend on the resolution and radial depth of penetration of the logging method. It systematically increased in the following order: {delta}(RHOB) < {delta}(CALI) < {delta}(PEF) < {delta}(URAN) < {delta}(GR) < {delta}(NPHI) < {delta}(POTA) < {delta}(CGR) < {delta}(THOR) < {delta}(MSFL) < {delta}(DRHO) < {delta}(LLS) < {delta}(LLD). [Spanish] En este trabajo fueron analizadas las variaciones fractales y de lagunaridad de los registros geofisicos de pozo, con el fin de asociarlos con las propiedades estratigraficas y petrofisicas del yacimiento naturalmente fracturado de Cantarell, en el Golfo de Mexico. Los registros considerados fueron: porosidad neutron (NPHI), densidad (RHOB, DRHO, PEF), resistividad (LLD, LLS, MSFL), radiactividad natural (GR, CGR, URAN, POTA, THOR) y caliper (CALI). Los registros de resistividad produjeron valores de lagunaridad notablemente altos, especialmente en las rocas generadoras y almacenadoras, a diferencia de los demas registros, cuya homogeneidad de traza implico una baja lagunaridad. Los resultados indican que la lagunaridad observada depende de la resolucion y profundidad radial de penetracion del metodo geofisico estudiado y aumenta sistematicamente en el siguiente orden: {delta}(RHOB) < {delta}(CALI) < {delta}(PEF) < {delta}(URAN) < {delta}(GR) < {delta}(NPHI) < {delta}(POTA) < {delta}(CGR) < {delta}(THOR) < {delta}(MSFL) < {delta}(DRHO) < {delta}(LLS) < {delta}(LLD).

  7. The cast imaging of the osteon lacunar-canalicular system and the implications with functional models of intracanalicular flow.

    Science.gov (United States)

    Pazzaglia, Ugo E; Congiu, Terenzio

    2013-02-01

    A casting technique with methyl-methacrylate (MMA) was applied to the study of the osteon lacunar-canalicular network of human and rabbit cortical bone. The MMA monomer infiltration inside the vascular canals and from these into the lacunar-canalicular system was driven by capillarity, helped by evaporation and the resulting negative pressure in a system of small pipes. There was uniform, centrifugal penetration of the resin inside some osteons, but this was limited to a depth of four to five layers of lacunae. Moreover, not all of the osteon population was infiltrated. This failure can be the result of one of two factors: the incomplete removal of organic debris from the canal and canalicular systems, and lack of drainage at the osteon external border. These data suggest that each secondary osteon is a closed system with a peripheral barrier (represented by the reversal line). As the resin advances into the osteon, the air contained inside the canalicula is compressed and its pressure increases until infiltration is stopped. The casts gave a reliable visualization of the lacunar shape, position and connections between the lacunae without the need for manipulations such as cutting or sawing. Two systems of canalicula could be distinguished, the equatorial, which connected the lacunae (therefore the osteocytes) lying on the same concentric level, and the radial, which established connections between different levels. The equatorial canalicula radiated from the lacunar border forming ramifications on a planar surface around the lacuna, whereas the radial canalicula had a predominantly straight direction perpendicular to the equatorial plane. The mean length of the radial canalicula was 40.12 ± 10.26 μm in rabbits and 38.4 ± 7.35 μm in human osteons; their mean diameter was 174.4 ± 71.12 nm and 195.7 ± 79.58 nm, respectively. The mean equatorial canalicula diameter was 237 ± 66.04 nm in rabbit and 249.7 ± 73.78 nm in human bones, both significantly larger (P

  8. Spatial distribution of lacunarity of voxelized airborne LiDAR point clouds in various forest assemblages

    Science.gov (United States)

    Székely, Balázs; Kania, Adam; Standovár, Tibor; Heilmeier, Hermann

    2015-04-01

    Forest ecosystems have characteristic structure of features defined by various structural elements of different scales and vertical positions: shrub layers, understory vegetation, tree trunks, and branches. Furthermore in most of the cases there are superimposed structures in distributions (mosaic or island patterns) due to topography, soil variability, or even anthropogenic factors like past/present forest management activity. This multifaceted spatial context of the forests is relevant for many ecological issues, especially for maintaining forest biodiversity. Our aim in this study is twofold: (1) to quantify this structural variability laterally and vertically using lacunarity, and (2) to relate these results to relevant ecological features, i.e quantitatively described forest properties. Airborne LiDAR data of various quality and point density have been used for our study including a number of forested sites in Central and East Europe (partly Natura 2000 sites). The point clouds have been converted to voxel format and then converted to horizontal layers as images. These images were processed further for the lacunarity calculation. Areas of interest (AOIs) have been selected based on evaluation of the forested areas and auxiliary field information. The calculation has been performed for the AOIs for all available vertical data slices. The lacunarity function referring to a certain point and given vicinity varies horizontally and vertically, depending on the vegetation structure. Furthermore, the topography may also influence this property as the growth of plants, especially spacing and size of trees are influenced by the local topography and relief (e.g., slope, aspect). The comparisons of the flatland and hilly settings show interesting differences and the spatial patterns also vary differently. Because of the large amount of data resulting from these calculations, sophisticated methods are required to analyse the results. The large data amount then has been

  9. Airborne pollutants and lacunar stroke: a case cross-over analysis on stroke unit admissions.

    Science.gov (United States)

    Corea, Francesco; Silvestrelli, Giorgio; Baccarelli, Andrea; Giua, Alessandra; Previdi, Paolo; Siliprandi, Giorgio; Murgia, Nicola

    2012-06-14

    Particulate air pollution is known to be associated with cardiovascular disease. The relation of particulate air pollution with cerebrovascular disease (CVD) has not been extensively studied, particularly in relation to different subtypes of stroke. A time-series study was conducted to evaluate the association between daily air pollution and acute stroke unit hospitalizations in Mantua, Italy. We analyzed 781 CVD consecutive patients living in Mantua county admitted between 2006-08. Data on stroke types, demographic variables, risk factors were available from the Lombardia Stroke Registry. Daily mean value of particulate matter with a diameter <10 µm (PM(10)), carbon monoxide, nitric oxide, nitrogen dioxide, sulphur dioxide, benzene and ozone were used in the analysis. The association between CVD, ischemic strokes subtypes and pollutants was investigated with a case-crossover design, using conditional logistic regression analysis, adjusting for temperature, humidity, barometric pressure and holidays. Among the 781 subjects admitted 75.7% had ischemic stroke, 11.7% haemorrhagic stroke 12.6% transient ischemic attack. In men admission for stroke was associated with PM(10) [odds ratio (OR) 1.01, 95%; confidence interval (CI) 1.00-1.02; P<0.05]. According to the clinical classification, lacunar anterior circulation syndrome stroke type was related to PM(10) level registered on the day of admission for both genders (OR: 1.01, 95%; CI: 1.00-1.02; P<0.05) while for total anterior circulation syndrome stroke only in men (OR: 1.04, 95%; CI 1.01-1.07; P<0.05).In conclusion, our study confirms that air pollution peaks may contribute to increase the risk of hospitalization for stroke and particulate matter seems to be a significant risk factor, especially for lacunar stroke.

  10. Lacunar stroke in a teenager after minor head trauma: case report and literature review.

    Science.gov (United States)

    Zwank, Michael D; Dummer, Benjamin W; Danielson, Levi T; Haake, Bret C

    2014-09-01

    Ischemic strokes in children and young adults are fortunately rare. Contrasted with adult ischemic strokes, pediatric stroke etiologies vary greatly and are often unknown. Childhood lacunar strokes and trauma-induced strokes represent particularly uncommon subsets and have been reported infrequently in the literature. It is unique to find a combination of the 2-a lacunar stroke induced by trauma. Underreporting of these trauma-induced ischemic strokes could be responsible for perpetuating the lack of recognition. Here we present a lacunar stroke in a young woman associated with a water sport accident and explore relevant literature encircling deep brain ischemia coinciding with trauma.

  11. Neuropsychological correlates of a right unilateral lacunar thalamic infarction

    Science.gov (United States)

    Werf, Y; Weerts, J; Jolles, J; Witter, M; Lindeboom, J; Scheltens, P.

    1999-01-01

    OBJECTIVES—To report on a patient with a lacunar infarction in the right intralaminar nuclei of the thalamus. The role of the thalamic intralaminar nuclei in cognitive function is as yet insufficiently known. The patient described has shown signs of apathy and loss of initiative, in combination with cognitive deficits, which have persisted essentially unaltered up to the present day since an abrupt onset 17 years ago.
METHODS—High resolution MRI was performed to show the extent of the lesion; a combination of published and experimental neuropsychological techniques was administered to show the nature of the cognitive defects; Single photon emission computed tomography (SPECT) was employed to obtain a measure of cortical perfusion.
RESULTS—Brain MRI disclosed an isolated lacunar infarction in the dorsal caudal intralaminar nuclei of the thalamus. Neuropsychological evaluation indicated problems with attention and concentration, executive disturbances, and memory deficits both in the visual and verbal domains. The memory deficits could not be attributed to problems in the early stages of information processing, and are hence regarded as resulting from a failure of retrieval rather than encoding or storage. Brain SPECT disclosed a hypoperfusion of the right frontal cortex.
CONCLUSION—The data indicate that the cognitive profile is the result of a dysfunction of executive functions. This is corroborated by the finding of decreased blood flow in the right frontal cortex, and by evidence from the neuroanatomical literature. Thus the dysexecutive symptoms are thought to be caused by disconnection of the prefrontal cortex from the brainstem activating nuclei through the strategic localisation of the right thalamic infarction.

 PMID:9886448

  12. EVALUATION OF VERTICAL LACUNARITY PROFILES IN FORESTED AREAS USING AIRBORNE LASER SCANNING POINT CLOUDS

    Directory of Open Access Journals (Sweden)

    B. Székely

    2016-06-01

    Logarithms of lacunarity functions show canopy-related variations, we analysed these variations along transects. The spatial variation can be related to forest properties and ecology-specific aspects.

  13. Tug-of-war lacunarity—A novel approach for estimating lacunarity

    Science.gov (United States)

    Reiss, Martin A.; Lemmerer, Birgit; Hanslmeier, Arnold; Ahammer, Helmut

    2016-11-01

    Modern instrumentation provides us with massive repositories of digital images that will likely only increase in the future. Therefore, it has become increasingly important to automatize the analysis of digital images, e.g., with methods from pattern recognition. These methods aim to quantify the visual appearance of captured textures with quantitative measures. As such, lacunarity is a useful multi-scale measure of texture's heterogeneity but demands high computational efforts. Here we investigate a novel approach based on the tug-of-war algorithm, which estimates lacunarity in a single pass over the image. We computed lacunarity for theoretical and real world sample images, and found that the investigated approach is able to estimate lacunarity with low uncertainties. We conclude that the proposed method combines low computational efforts with high accuracy, and that its application may have utility in the analysis of high-resolution images.

  14. Millennium Simulation Dark Matter Haloes: Multi-fractal and Lacunarity Analysis with Homogeneity Transition

    CERN Document Server

    Chacón-Cardona, César A

    2012-01-01

    We investigate from the fractal viewpoint the way in which the dark matter is grouped at z = 0 in the Millennium dark matter cosmological simulation. The determination of the cross to homogeneity in the Millennium Simulation data is described from the behaviour of the fractal dimension and the lacunarity. We use the sliding window technique to calculate the fractal mass-radius dimension, the pre-factor F and the lacunarity of this fractal relation. Besides, we determinate the multi-fractal dimension and the lacunarity spectrum, including their dependence with radial distance. This calculations show a radial distance dependency of all the fractal quantities, with heterogeneity clustering of dark matter haloes up to depths of 100 Mpc/h. The dark matter haloes clustering in the Millennium Simulation shows a radial distance dependency, with two regions clearly defined. The lacunarity spectrum for values of the structure parameter q >= 1 shows regions with relative maxima, revealing the formation of clusters and v...

  15. Neural differentiation of transplanted neural stem cells in a rat model of striatal lacunar infarction: light and electron microscopic observations

    Directory of Open Access Journals (Sweden)

    Vilma Consuelo Muñeton-Gomez

    2012-08-01

    Full Text Available The increased risk and prevalence of lacunar stroke and Parkinson's disease makes the search for better experimental models an important requirement for translational research. In this study we assess ischemic damage of the nigrostriatal pathway in a model of lacunar stroke evoked by damaging the perforating arteries in the territory of the substantia nigra of the rat after stereotaxic administration of endothelin-1, a potent vasoconstrictor peptide. We hypothesized that transplantation of neural stem cells (NSCs with the capacity of differentiating into diverse cell types such as neurons and glia, but with limited proliferation potential, would constitute an alternative and/or adjuvant therapy for lacunar stroke. These cells showed neuritogenic activity in vitro and a high potential for neural differentiation. Light and electron microscopy immunocytochemistry was used to characterize green fluorescent-derived neurons. 48h after endothelin-1 injection, we characterized an area of selective degeneration of dopaminergic neurons within the nigrostriatal pathway characterised with tissue necrosis and glial scar formation, with subsequent behavioral signs of Parkinsonism. Light microscopy showed that grafted cells within the striatal infarction zone differentiated with a high yield into mature glial cells (GFAP-positive and into neurons of diverse neurotransmitter-striatal subtypes, suggesting that they were functional. Electron microscopy revealed that NSCs-derived neurons integrated into the host circuitry establishing synaptic contacts, mostly of the asymmetric type. Astrocytes were closely associated with normal small-sized blood vessels in the area of infarct, suggesting their implication in angiogenesis during recovery from stroke. Our results encourage the use of NSCs as a cell-replacement therapy for the treatment of human vascular Parkinsonism.

  16. Identifying mangrove species and their surrounding land use and land cover classes using object-oriented approach with a lacunarity spatial measure

    Science.gov (United States)

    Myint, S.W.; Giri, C.P.; Wang, L.; Zhu, Z.; Gillete, S.C.

    2008-01-01

    Accurate and reliable information on the spatial distribution of mangrove species is needed for a wide variety of applications, including sustainable management of mangrove forests, conservation and reserve planning, ecological and biogeographical studies, and invasive species management. Remotely sensed data have been used for such purposes with mixed results. Our study employed an object-oriented approach with the use of a lacunarity technique to identify different mangrove species and their surrounding land use and land cover classes in a tsunami-affected area of Thailand using Landsat satellite data. Our results showed that the object-oriented approach with lacunarity-transformed bands is more accurate (over-all accuracy 94.2%; kappa coefficient = 0.91) than traditional per-pixel classifiers (overall accuracy 62.8%; and kappa coefficient = 0.57). Copyright ?? 2008 by Bellwether Publishing, Ltd. All rights reserved.

  17. The relation between prognosis and nocturnal blood pressure variation in hypertensive patients with lacunar infarct%夜间血液变化与高血压腔隙性脑梗死发后及预后的相关性分析

    Institute of Scientific and Technical Information of China (English)

    张微微; 黄勇华; 李娟; 冯军

    2001-01-01

    Objective We conducted a study using MRI and ambulatory blood pressure monitoring(ABPM) to determine whether an inapporpriately low nocturnal blood pressure,or an excess fall in nocturnal blood pressure,might be responsible for lacunar infarct.Method ABPM and Casul blood pressure(CBP) were examined in 35 hypertentives with lacunar infarct( LI) and 33 hypertentives without lacunar infarct as control group.Results There is no significant difference of CBP between two groups.But the mean nighttime systolic blood pressure(nSBP) and diastolic blood pressure(nDBP) in patients with lacunar infarct were significantly smaller than in patients without lacunar infarct.The ratio of nSBP/dSBP and nDBP/dDBP in SI were smaller than in control group respectively.Conclusions The results indicate that an inappropriately low nocturnal blood pressure,or an excessive fall in nocturnal blood pressure,is associated with lacunar infarct.It is necessary not only to controlhigh blood pressure but also to pay attention to circadian changes of blood pressure during the course of anti-hypertensive treatment.

  18. Lacunar infarcts in childhood. Clinical and computed tomographic correlations

    Energy Technology Data Exchange (ETDEWEB)

    Nakano, Chizuko; Eda, Isematsu; Takashima, Sachio; Takeshita, Kenzo (Tottori Univ., Yonago (Japan). School of Medicine); Kanetoh, Yasuko

    1984-09-01

    Nine cases, ranging in age from 6 months to 9 years, were diagnosed as lacunar infarcts on computed tomography (CT). Hemiplegia developed rapidly or gradually in 8 cases. Three of 8 cases had transient ischemic attacks of hemiplegia. Other neurological deficits were dysarthria, aphasia, confusion and coarse tremor. One case was asymptomatic. Each of 8 cases had single lacuna and one case two lacunae on CT. These lacunae were localized in the internal capsule, the putamen or the caudate nucleus. Lacunae involving the internal capsule were associated with contralateral hemiplegia, whereas asymptomatic lacunae did not involve it. Severity of hemiplegia in the acute stage did not correlate with localization or size of lacunae. Moderate neurological sequelae were noticed in 3 cases, mild sequelae in two and none in three. The sequelae were related to the lacunae which involved the lateral lenticulostriate branch zone of the middle cerebral artery or larger areas. Prognosis did not correlate with the mode of onset or the severity of neurological signs in the acute stage. There were 2 cases with the occlusion of the left internal carotid artery or congenital heart disease, but the etiology of lacunae was unknown in the other cases.

  19. The usefulness of diffusion-weighted/fluid-attenuated inversion recovery imaging in the diagnostics and timing of lacunar and nonlacunar stroke

    Energy Technology Data Exchange (ETDEWEB)

    Witkowski, Grzegorz; Sienkiewicz-Jarosz, Halina [Institute of Psychiatry and Neurology, 1st Department of Neurology, Warsaw (Poland); Piliszek, Agnieszka; Ryglewicz, Danuta [Central Clinical Hospital of the Ministry of Interior, Department of Radiology, Warsaw (Poland); Skierczynska, Agnieszka; Poniatowska, Renata [Institute of Psychiatry and Neurology, Department of Radiology, Warsaw (Poland); Dorobek, Malgorzata; Filipek-Gliszczynska, Anna [Central Clinical Hospital of the Ministry of Interior, Department of Neurology, Warsaw (Poland); Walecki, Jerzy [Polish Academy of Science, Mossakowski Medical Research Centre, Warsaw (Poland)

    2014-10-15

    The DWI/FLAIR mismatch is a potential radiological marker for the timing of stroke onset. The aim of the study was to assess if the DWI/FLAIR mismatch can help to identify patients with both lacunar and nonlacunar acute ischemic stroke within 4.5 h of onset. A retrospective study was performed in which the authors analysed data from 86 ischemic lacunar and nonlacunar stroke patients with a known time of symptom onset, imaged within the first 24 h from stroke onset (36 patients <4.5 h, 14 patients 4.5-6 h, 15 patients 6-12 h, and 21 patients 12-24 h). Patients underwent the admission CT and MR scan. The presence of lesions was assessed in correlation with the duration of the stroke. The time from stroke onset to neuroimaging was significantly shorter in patients with an ischemic lesion visible only in the DWI (mean 2.78 h, n = 24) as compared to patients with signs of ischemia also in other modalities (mean 8.6 h, n = 62) (p = 0.0001, Kruskal-Wallis ANOVA). The DWI/FLAIR mismatch was characterised by a global sensitivity of 58 %, specificity 94 %, PPV 87.5 %, and NPV 76 % in identifying patients in the 4.5 h thrombolysis time window. For lacunar strokes (n = 20), these parameters were as follows: sensitivity 50 %, specificity 92.8 %, PPV 75 %, and NPV 81.2 %. The presence of acute ischemic lesions only in DWI can help to identify both lacunar and nonlacunar stroke patients who are in the 4.5 h time window for intravenous thrombolysis with high specificity. (orig.)

  20. Correlation between transcranial Doppler blood flow parameters and degree of nerve injury, degree of inflammation as well as Hcy metabolism in patients with lacunar infarction

    Institute of Scientific and Technical Information of China (English)

    Li Liang; Jin-Hua Su; Hai-Yan Kou

    2016-01-01

    Objective:To study the correlation between transcranial Doppler blood flow parameters and the degree of nerve injury, the degree of inflammation as well as Hcy metabolism in patients with lacunar infarction.Methods:A total of 88 patients diagnosed with lacunar infarction (LI) in our hospital between May 2013 and December 2015 were selected as LI group and 100 healthy volunteers receiving physical examination during the same period were selected as control group. Transcranial Doppler was used to measure the blood flow parameters of middle cerebral artery and basilar artery, and serum was collected to determine nerve injury molecules, inflammation indexes and Hcy metabolism indexes.Results:Middle cerebral artery MFV and PI as well as basal artery MFV and PI of LI group were significantly higher than those of control group; serum NSE, S100B, UCH-L1, ox-LDL, MMP-9, sCD40L, IL-18 and Hcy content of LI group were significantly higher than those of control group and positively correlated with middle cerebral artery and basilar artery MFV and PI while folic acid and vitamin B12 content were significantly lower than those of control group and negatively correlated with middle cerebral artery and basilar artery MFV and PI.Conclusions:Middle cerebral artery and basilar artery flow is accelerated and the pulsatility is enhanced in patients with lacunar infarction, and the changes of intracranial artery flow parameters are closely related to the degree of nerve injury, the degree of inflammation and Hcy metabolism.

  1. Fractal Dimension and Lacunarity analysis of mammographic patterns in assessing breast cancer risk related to HRT treated population

    DEFF Research Database (Denmark)

    Karemore, Gopal Raghunath; Nielsen, Mads

    2009-01-01

    and 36 HRT treated volunteers for two years. ROIs with same dimension (250*150 pixels) were created behind the nipple region on these radiographs. Box counting method was used to calculate the fractal dimension (FD) and the Lacunarity. Paired t-test and Pearson correlation coefficient were calculated...... significantly (Pcorrelated to Lacunarity (-0.74, P

  2. Acute lacunar infarcts in CLIPPERS: is the chronic infiltrative lymphocytic perivascular disease process to blame?

    Science.gov (United States)

    Saigal, Gaurav; Quencer, Robert

    2013-12-01

    CLIPPERS (chronic lymphocytic inflammation with pontine perivascular enhancement responsive to steroids) is a recently described chronic inflammatory disorder involving the brainstem with characteristic imaging findings. Since it was originally described in 2002, only a handful of cases have been reported in the literature. We describe two additional cases of CLIPPERS with characteristic clinical and radiological findings. Besides the previously described MR findings, one of the cases also demonstrated multiple basal ganglia lacunar infarcts, a finding which has not been previously reported. We hypothesize that the lacunar infarcts are caused by this chronic infiltrative perivascular disease process.

  3. Plasma tPA-Activity and Progression of Cerebral White Matter Hyperintensities in Lacunar Stroke Patients

    Science.gov (United States)

    van Overbeek, Ellen C.; Staals, Julie; Knottnerus, Iris L. H.; ten Cate, Hugo; van Oostenbrugge, Robert J.

    2016-01-01

    Introduction Tissue plasminogen activator (tPA)-activity and plasminogen activator inhibitor type 1 (PAI-1) antigen are considered to be haemostasis-related markers of endothelial activation and relate to presence of cerebral white matter hyperintensities (WMH) as was earlier shown in a cross-sectional study. We investigated whether tPA-activity and PAI-1 levels are associated with WMH progression in a longitudinal study. Methods In 127 first-ever lacunar stroke patients in whom baseline brain MRI and plasma levels of tPA-activity and PAI-1-antigen were available, we obtained a 2-year follow-up MRI. We assessed WMH progression by a visual WMH change scale. We determined the relationship between levels of tPA-activity and PAI-1 and WMH progression, by logistic regression analysis. Results Plasma tPA-activity was associated with periventricular WMH progression (OR 2.36, 95% CI 1.01–5.49, with correction for age and sex and baseline presence of WMH), but not with deep or any (periventricular and/or deep) WMH progression. PAI-1 levels were lower in patients with WMH progression, but these results were not significant. Conclusion We found a relationship between plasma tPA-activity and progression of periventricular WMH. More research is needed to determine whether there is a (direct) role of tPA in the development and progression of WMH. PMID:26942412

  4. Plasma tPA-Activity and Progression of Cerebral White Matter Hyperintensities in Lacunar Stroke Patients.

    Directory of Open Access Journals (Sweden)

    Ellen C van Overbeek

    Full Text Available Tissue plasminogen activator (tPA-activity and plasminogen activator inhibitor type 1 (PAI-1 antigen are considered to be haemostasis-related markers of endothelial activation and relate to presence of cerebral white matter hyperintensities (WMH as was earlier shown in a cross-sectional study. We investigated whether tPA-activity and PAI-1 levels are associated with WMH progression in a longitudinal study.In 127 first-ever lacunar stroke patients in whom baseline brain MRI and plasma levels of tPA-activity and PAI-1-antigen were available, we obtained a 2-year follow-up MRI. We assessed WMH progression by a visual WMH change scale. We determined the relationship between levels of tPA-activity and PAI-1 and WMH progression, by logistic regression analysis.Plasma tPA-activity was associated with periventricular WMH progression (OR 2.36, 95% CI 1.01-5.49, with correction for age and sex and baseline presence of WMH, but not with deep or any (periventricular and/or deep WMH progression. PAI-1 levels were lower in patients with WMH progression, but these results were not significant.We found a relationship between plasma tPA-activity and progression of periventricular WMH. More research is needed to determine whether there is a (direct role of tPA in the development and progression of WMH.

  5. Evaluation of Vertical Lacunarity Profiles in Forested Areas Using Airborne Laser Scanning Point Clouds

    Science.gov (United States)

    Székely, B.; Kania, A.; Standovár, T.; Heilmeier, H.

    2016-06-01

    The horizontal variation and vertical layering of the vegetation are important properties of the canopy structure determining the habitat; three-dimensional (3D) distribution of objects (shrub layers, understory vegetation, etc.) is related to the environmental factors (e.g., illumination, visibility). It has been shown that gaps in forests, mosaic-like structures are essential to biodiversity; various methods have been introduced to quantify this property. As the distribution of gaps in the vegetation is a multi-scale phenomenon, in order to capture it in its entirety, scale-independent methods are preferred; one of these is the calculation of lacunarity. We used Airborne Laser Scanning point clouds measured over a forest plantation situated in a former floodplain. The flat topographic relief ensured that the tree growth is independent of the topographic effects. The tree pattern in the plantation crops provided various quasi-regular and irregular patterns, as well as various ages of the stands. The point clouds were voxelized and layers of voxels were considered as images for two-dimensional input. These images calculated for a certain vicinity of reference points were taken as images for the computation of lacunarity curves, providing a stack of lacunarity curves for each reference points. These sets of curves have been compared to reveal spatial changes of this property. As the dynamic range of the lacunarity values is very large, the natural logarithms of the values were considered. Logarithms of lacunarity functions show canopy-related variations, we analysed these variations along transects. The spatial variation can be related to forest properties and ecology-specific aspects.

  6. Airborne pollutants and lacunar stroke. A case cross-over analysis on stroke unit admissions

    Directory of Open Access Journals (Sweden)

    Nicola Murgia

    2012-06-01

    Full Text Available Particulate air pollution is known to be associated with cardiovascular disease. The relation of particulate air pollution with cerebrovascular disease (CVD has not been extensively studied, particularly in relation to different subtypes of stroke. A time-series study was conducted to evaluate the association between daily air pollution and acute stroke unit hospitalizations in Mantua county (Italy. We analyzed 781 CVD consecutive patients living in Mantua county admitted between 2006-08. Data on stroke types, demographic variables, risk factors were available from the Lombardia Stroke Registry. Daily mean value of particulate matter with a diameter < 10 μm (PM10, carbon monoxide, nitric oxide, nitrogen dioxide, sulphur dioxide, benzene and ozone were used in the analysis. The association between CVD, ischemic strokes subtypes and pollutants was investigated with a casecrossover design, using conditional logistic regression analysis, adjusting for temperature, humidity, barometric pressure and holidays. Among the 781 subjects admitted 75.7% had ischemic stroke, 11.7% haemorrhagic stroke 12.6% transient ischemic attack. In men admission for stroke was associated with PM10 (OR 1.01, 95% CI 1.00-1.02, p<0.05 . According to the clinical classification, LACI stroke type was related to PM10 level registered on the day of admission for both genders (OR 1.01, 95% CI 1.00-1.02, p<0.05 while for TACI stroke only in men (OR: 1.04, 95% CI 1.01-1.07, p<0.05. Our study confirms that air pollution peaks may contribute to increase the risk of hospitalization for stroke and particulate matter seems to be a significant risk factor, especially for lacunar stroke.

  7. Perfusion-weighted imaging and dynamic 4D angiograms for the estimation of collateral blood flow in lacunar infarction.

    Science.gov (United States)

    Förster, Alex; Mürle, Bettina; Böhme, Johannes; Al-Zghloul, Mansour; Kerl, Hans U; Wenz, Holger; Groden, Christoph

    2016-10-01

    Although lacunar infarction accounts for approximately 25% of ischemic strokes, collateral blood flow through anastomoses is not well evaluated in lacunar infarction. In 111 lacunar infarction patients, we analyzed diffusion-weighted images, perfusion-weighted images, and blood flow on dynamic four-dimensional angiograms generated by use of Signal Processing In NMR-Software. Blood flow was classified as absent (type 1), from periphery to center (type 2), from center to periphery (type 3), and combination of type 2 and 3 (type 4). On diffusion-weighted images, lacunar infarction was found in the basal ganglia (11.7%), internal capsule (24.3%), corona radiata (30.6%), thalamus (24.3%), and brainstem (9.0%). In 58 (52.2%) patients, perfusion-weighted image showed a circumscribed hypoperfusion, in one (0.9%) a circumscribed hyperperfusion, whereas the remainder was normal. In 36 (62.1%) patients, a larger perfusion deficit (>7 mm) was observed. In these, blood flow was classified type 1 in four (11.1%), 2 in 17 (47.2%), 3 in 9 (25.0%), and 4 in six (16.7%) patients. Patients with lacunar infarction in the posterior circulation more often demonstrated blood flow type 2 and less often type 3 (p = 0.01). Detailed examination and graduation of blood flow in lacunar infarction by use of dynamic four-dimensional angiograms is feasible and may serve for a better characterization of this stroke subtype.

  8. Xueshuantong improves cerebral blood perfusion in elderly patients with lacunar infarction

    Institute of Scientific and Technical Information of China (English)

    Qifeng Gui; Yunmei Yang; Shihong Ying; Minming Zhang

    2013-01-01

    A total of 64 patients with acute lacunar infarction were enrolled within 24 hours of onset. The patients received conventional therapy (antiplatelet drugs and hypolipidemic drugs) alone or conventional therapy plus 450 mg Xueshuantong once a day. The main ingredient of the Xueshuantong lyophilized powder used for injection was Panax notoginseng saponins. Assessments were made at admission and at discharge using the National Institutes of Health Stroke Scale, the Activity of Daily Living and the Mini-Mental State Examination. Additionally, the relative cerebral blood flow, relative cerebral blood volume and relative mean transit time in the region of interest were calculated within 24 hours after the onset of lacunar infarction, using dynamic susceptibility contrast magnetic resonance perfusion imaging technology. Patients underwent a follow-up MRI scan after 4 weeks of treatment. There was an improvement in the Activity of Daily Living scores and a greater reduction in the scores on the National Institutes of Health Stroke Scale in the treatment group than in the control group. However, the Mini-Mental State Examination scores showed no significant differences after 4 weeks of treatment. Compared with the control group, the relative cerebral blood flow at discharge had increased and showed a greater improvement in the treatment group. Furthermore, there was a reduction in the relative mean transit time at discharge and the value was lower in the treatment group than in the control group. The experimental findings indicate that Xueshuantong treatment improves neurological deficits in elderly patients with lacunar infarction, and the mechanism may be related to increased cerebral perfusion.

  9. SISTEM VERIFIKASI BIOMETRIKA TELAPAK TANGAN DENGAN METODE DIMENSI FRAKTAL DAN LACUNARITY

    Directory of Open Access Journals (Sweden)

    Ketut Gede Darma Putra

    2009-12-01

    Full Text Available Sistem pengenalan diri secara otomatis dengan telapak tangan merupakan teknologi biometrika yang masih relatif baru. Permasalahan utama dalam sistem pengenalan dengan telapak tangan adalah bagaimana memperoleh ciri telapak tangan tersebut. Penelitian ini memperkenalkan pendekatan baru untuk menghasilkan ciri telapak tangan yaitu dimensi fraktal dan derajat kekosongan fraktal (lacunarity. Skor pencocokan dua telapak tangan dihitung dengan metrika korelasi. Sistem diuji menggunakan sekitar 1250 telapak tangan milik 250 responden. Hasil percobaan menunjukkan sistem mampu menghasilkan tingkat keberhasilan sekitar 98%  atau FAR = 1.9139 %, FRR = 1.9139%, T = 0.2364.

  10. Capsular warning syndrome and crescendo lacunar strokes after atherosclerotic stenosis of the recurrent artery of Heubner.

    Science.gov (United States)

    Cohen, José E; Rabinstein, Alejandro; Gomori, John M; Leker, Ronen R

    2012-12-01

    The stereotype of repetitive transient cerebral ischemia causing unilateral motor, sensory, or sensorimotor deficits that simultaneously affect the face, arm, and leg, clinically localized to the internal capsule, fits with the description of capsular warning syndrome (CWS). A high proportion of individuals with these symptoms develop subsequent capsular stroke, despite various proposed preventative measures. It has been postulated that the mechanism for such strokes is that of small-vessel single-penetrator disease. We present a patient with repetitive CWS intermingled with crescendo capsular strokes secondary to recurrent artery of Heubner disease. This report causally links CWS-crescendo lacunar strokes and Heubner artery atherosclerotic disease (intracranial branch atheromatous disease).

  11. Multifractal analysis and lacunarity spectrum of the galaxies of the ninth Sloan Digital Sky Survey (SDSS) data release

    CERN Document Server

    Chacón-Cardona, César A

    2012-01-01

    In this work, we develop a statistical analysis of the large-scale clustering of matter in the Universe from the fractal point of view using galaxies from the Ninth Sloan Digital Sky Survey (SDSS) Data Release (DR9). From the total set of galaxies, a magnitude-limited sample of galaxies with redshifts in the range 0 < z < 0.15 was created. The sample covers the largest completely connected area of the celestial sphere within the catalogue, with limits in right ascension from 120 to 240 degrees and declination from 0 to 60 degrees, which is a region that includes the largest galactic samples that have been studied from the fractal viewpoint to date. The sample contains 164,168 galaxies. Using the sliding-window technique, the multifractal dimension spectrum and its dependence on radial distance are determined. This generalisation of the concept of fractal dimension is used to analyse large-scale clustering of matter in complex systems. Likewise, the lacunarity spectrum, which is a quantity that complemen...

  12. Validity of apparent diffusion coefficient hyperpolarized 3He-MRI using MSCT and pulmonary function tests as references

    DEFF Research Database (Denmark)

    Diaz, Sandra; Casselbrant, Ingrid; Piitulainen, Eeva;

    2008-01-01

    PURPOSE: To compare apparent diffusion coefficient (ADC) measurements from hyperpolarized (HP) helium ((3)He)-magnetic resonance imaging (MRI) with quantitative data from multislice Computed Tomography (CT) (MSCT) of the whole lungs and pulmonary function tests (PFT). MATERIALS AND METHODS: Twenty...... from MSCT. Both mean ADC and MSCT data were compared to PFT, especially percent of predicted diffusing capacity of carbon monoxide (%predicted DLCO), using Pearson's correlation test. RESULTS: Mean ADC and standard deviation values were 0.392+/-0.119 cm(2)/s for the established emphysema group and 0...

  13. 腔隙性卒中后疲劳与认知障碍和抑郁的相关性:回顾性病例系列研究%Correlation between fatigue and cognitive impairment and depression in patients with lacunar stroke: a retrospective case series study

    Institute of Scientific and Technical Information of China (English)

    王明红; 艾清龙

    2012-01-01

    目的 探讨腔隙性卒中后疲劳与认知障碍和抑郁的相关性.方法 纳入2009年9月至2010年11月期间住院的103例腔隙性卒中患者,采用疲劳量表-14(Fatigue Scale,FS-14)、疲劳严重程度量表(Fatigue Severity Scale,FSS-9)评价卒中后疲劳,简易精神状态检查量表(Mini-Mental State Examinat ion,MMSE)和蒙特利尔认知评估量表(Montreal Cognitive Assessment,MoCA)评价认知功能,抑郁自评量表(Self-Rating Depression Scale,SDS)和汉密尔顿抑郁量表(Hamilton Depression Scale,HAMD)评价抑郁情况.结果 通过不同量表评定,分别有34例(33.01%) (FSS-9)和45例(43.69%)(FS-14)存在疲劳.在根据FSS-9评分确定的34例疲劳患者中,有20例存在认知损害,26例存在抑郁,16例同时存在认知损害和抑郁.Pearson相关分析显示,FS-14评分与MMSE评分(r=-0.307,P =0.002)和MoCA评分(r=-0.457,P=0.000)呈显著负相关,而与SDS评分(r=0.368,P=0.000)和HAMD评分(r=0.526,P=0.000)呈显著正相关;FSS-9评分亦与MMSE评分(r=-0.292,P=0.003)和MoCA评分(r=-0.340,P=0.000)呈显著负相关,而与SDS评分(r=0.403,P=0.000)和HAMD评分(r=0.564,P=0.000)呈显著正相关.结论 腔隙性卒中患者的疲劳、认知损害和抑郁发生率均较高,疲劳与认知损害和抑郁之间存在一定的相关性.%Objective To investigate the correlation between fatigue and cognitive impairment and depression after lacunar stroke.Methods A total of 103 patients with lacunar infarction admitted from September 2009 to November 2010 were enrolled.Post-stroke fatigue was evaluated with the Fatigue Scale (FS-14) and the Fatigue Severity Scale (FSS-9); cognitive function was evaluated with the mini-mental state examination (MMSE) and the Montreal cognitive assessment (MoCA); and depression was evaluated with the self-rating depression scale (SDS) and the Hamilton Depression Rating Scale (HAMD).Results There were 34 patients (33.01%) (FSS-9) and 45 patients (43.69%) (FS-14) had fatigue

  14. Carbonic anhydrase levels and internal lacunar CO/sub 2/ concentrations in aquatic macrophytes

    Energy Technology Data Exchange (ETDEWEB)

    Weaver, C.I.

    1979-01-01

    Carbonic anhydrase levels were examined in a variety of aquatic macrophytes from different habitats. In general, carbonic anhydrase levels increased across the habitat gradient such that activities were low in submersed aquatic macrophytes and high in emergent macrophytes with floating-leaved and free-floating plants exhibiting intermediate activities. Internal lacunar CO/sub 2/ concentrations were analyzed in relation to carbonic anhydrase activities. There was no correlation between these two parameters. Internal CO/sub 2/ concentrations ranged from low to high in submersed macrophytes, but were low in floating-leaved and emergent macrophytes. The observed internal CO/sub 2/ concentrations are discussed in relation to the individual morphologies of the plants and the environments in which they occurred.

  15. Deterioration of pre-existing hemiparesis brought about by subsequent ipsilateral lacunar infarction.

    Science.gov (United States)

    Ago, T; Kitazono, T; Ooboshi, H; Takada, J; Yoshiura, T; Mihara, F; Ibayashi, S; Iida, M

    2003-08-01

    Mechanisms of post-stroke recovery are still poorly understood. Recent evidence suggests that cortical reorganisation in the unaffected hemisphere plays an important role. A 59 year old man developed a small lacunar infarct in the left corona radiata, which then caused marked deterioration in a pre-existing left hemiparesis that had resulted from an earlier right putaminal haemorrhage. Functional magnetic resonance imaging showed that the paretic left hand grip activated the ipsilateral left motor areas, but not the right hemispheric motor areas. This suggests that partial recovery of the left hemiparesis had been brought about by cortical reorganisation of the left hemisphere and intensification of the uncrossed corticospinal tract. The subsequent small infarct may have damaged the uncrossed tract, thereby causing the pre-existing hemiparesis to deteriorate even further.

  16. Treatment of Lacunar Cerebral Infarction with Huo Xue Tong Luo Tang

    Institute of Scientific and Technical Information of China (English)

    侯安会; 王亚威; 郑一

    2001-01-01

    @@Based on our clinical experience,we formulated Huo Xue Tong Luo Tang(活血通络汤HXTL Decoction),a prescription for treatment of lacunar cerebral infarction.Most of the ingredients are those in the prescriptions of Di Dang Tang(抵当汤)and Gui Gan Long Mu Tang(桂甘龙牡汤)described in the book Treatise of Febrile Diseases(伤寒论)in accordance with the compatible theory of principal,assistant,adjuvant and guiding drugs for improving blood circulation,removing stasis,dispelling endogenous wind and phlegm,inducing resuscitation,removing obstruction in the channels,and balancing the yin and yang.

  17. Cerebrovascular reserve in cerebral small vessel disease patients with lacunar infarction: a transcranial Doppler study%表现为腔隙性梗死的脑小血管病患者的脑血管储备:经颅多普勒研究

    Institute of Scientific and Technical Information of China (English)

    张伟劲; 高庆春; 杨容坤; 陈秀梅; 樊静; 杨继党; 王文君; 张波; 傅贤

    2014-01-01

    目的 探讨表现为腔隙性脑梗死(lacunar infarction,LI)的脑小血管病(cerebral small vessel disease,SVD)患者的脑血管储备(cerebrovascular reserve,CVR)变化.方法 纳入表现为LI的连续SVD患者(SVD组)和影像学检查正常的对照者(对照组).采用(transcranial Doppler,TCD)检测双侧大脑中动脉(middle cerebral artery,MCA)供血区CVR.比较SVD组与对照组人口统计学、临床资料、TCD参数和CVR,并采用多变量logistic回归分析确定CVR与SVD的相关性.结果 共纳入97例表现为LI的SVD患者和40名对照者.SVD组LI分级:1级34例,2级23例,3级40例.40名健康对照者均无LI病灶.SVD组高血压(58.8%对27.5%;x2=3.315,P=0.001)和男性患者(76.3%对50.0% 2=3.004,P=0.003)的构成比以及年龄[(64.5±10.0)岁对(59.5±8.0)岁;t=2.667,P=0.008]和体质指数(body mass index,BMI)[(24.47±3.16)kg/m2对(21.52 ±2.15) kg/m2;=5.409,P<0.001]均显著性高于对照组.MCA平均血流速度在正常范围,但SVD组右侧MCA搏动指数(pulsatility index,PI)显著性高于对照组(0.90±0.15对0.83±0.11;=2.286,P=0.024),SVD组左侧[(4.56±1.12)%/mm Hg对(7.42±0.62) %/mm Hg,1 mmHg=0.133kPa;t 18.93,P<0.000]和右侧[(4.62±1.00)%/mmHg对(7.43±0.59)%/mm Hg;t =20.45,P<0.001] CVR显著性低于对照组.多变量logistic回归分析显示,高血压[优势比(odds ratio,OR)3.757,95%可信区间(confidence interval,CI)1.683 ~8.388;P <0.001]、年龄较大(OR1.061,95% CI1.016~1.109;P=0.007)和BMI较高(OR1.428,1.224 ~ 1.667;P<0.001)为SVD的独立危险因素,男性(OR0.311,0.143 ~0.676;P =0.003)以及左侧(OR 0.025,95% CI0.005 ~0.116;P<0.001)和右侧(OR0.001,95% CI0.000~0.049;P<0.001)CVR较高为SVD的独立保护性因素.结论 表现为LI的SVD患者脑血流动力学主要表现为CVR降低,存在高血压、年龄较大、BMI较高是SVD的独立危险因素,丽男性和CVR较高是SVD的独立保护因素.%Objective To investigate the changes of

  18. 腔隙性脑梗死在原发性高血压患者危险分层中的意义%The significance of lacunar infarction in the risk stratification of essential hyertension

    Institute of Scientific and Technical Information of China (English)

    姚保明

    2011-01-01

    Objective: To study the significance of lacunar infarction in the risk stratification of essential hypertension. Methods: 214 patients with essential hypertension were divided into CLI group (lacunar infarction group), ACC group (related clinical conditions group) and TOD group (target organ damage group), then the damage degree of heart, renal and fundus of the three groups were compared. Results: The damage degree of heart, renal and fundus between CLI group and ACC group showed significant difference (ρ<0.01), the damage degree of heart, renal and fundus between CLI group and TOD group showed no significant difference (ρ>0.05). Conclusion: The lacunar infarction is index of risk stratification of essential hypertension, it shows the damage of heart, renal and fundus, the degree is similar to TOD, and should be the classification of TOD.%目的:探讨腔隙性脑梗死在原发性高血压危险分层中的意义.方法:241例原发性高血压患者被分为CLI组(腔隙性脑梗死组)、ACC组(相关临床情况组)和TOD组(靶器官损害组),比较三组间心、肾、眼底损害程度.结果:CLI组与ACC组间的心、肾及眼底损害程度比较,差异有统计学意义(P<0.01),CLI组与TOD组比较,差异无统计学意义(P>0.05).结论:腔隙性脑梗死作为原发性高血压危险分层中的指标,提示患者出现心、肾、眼底损害,其程度与TOD组相似,宜归为TOD组.

  19. Maximum entropy, fractal dimension and lacunarity in quantification of cellular rejection in myocardial biopsy of patients submitted to heart transplantation

    Energy Technology Data Exchange (ETDEWEB)

    Neves, L A [Universidade Estadual Paulista, IGCE, DEMAC, Rio Claro, SP (Brazil); Oliveira, F R; Peres, F A [Faculdade de Tecnologia de Sao Jose do Rio Preto, Sao Jose do Rio Preto, SP (Brazil); Moreira, R D; Moriel, A R; De Godoy, M F [Faculdade de Medicina de Sao Jose do Rio Preto, FAMERP, Sao Jose do Rio Preto, SP (Brazil); Murta Junior, L O, E-mail: laneves@rc.unesp.br [Universidade de Sao Paulo, FFCLRP, Depto Computacao e Matematica, Ribeirao Preto (Brazil)

    2011-03-01

    This paper presents a method for the quantification of cellular rejection in endomyocardial biopsies of patients submitted to heart transplant. The model is based on automatic multilevel thresholding, which employs histogram quantification techniques, histogram slope percentage analysis and the calculation of maximum entropy. The structures were quantified with the aid of the multi-scale fractal dimension and lacunarity for the identification of behavior patterns in myocardial cellular rejection in order to determine the most adequate treatment for each case.

  20. Spatial dispersion and clustering of soil structure through lacunarity of X-ray CT images of soil macropore volumes

    Science.gov (United States)

    San José Martínez, Fernando; Caniego, Javier; García-Gutiérrez, Carlos

    2016-04-01

    Lacunarity can be seen as a scale dependent measure of heterogeneity or texture ―in terms of image analysis― that was first introduced to quantify different patterns of dispersion and clustering that display geometrical objects with the same fractal dimension. Notwithstanding, lacunarity functions have been revealed as means to measure the deviation of object's geometrical structure from translational invariance beyond self-similarity and fractal geometry. In this work, we will explore how lacunarity quantifies different patterns of dispersion and clustering of different geometrical structures of soil macropore volumes imaged by X-ray computed tomography. Samples extracted from columns were collected at the experimental farm "Finca La Grajera" in La Rioja (Spain), property of La Rioja Regional Government (northern Spain). The vineyard selected was established in 1996. During the 1996 to 2004 period, the soil management was conventional tillage. Before the vineyard was established in 1996, a pasture-legume-cereal rotation was used. In 2004 an experiment was established with different types of soil cover management in between. On December 2010 columns were extracted vertically by percussion drilling between rows of the vineyard.

  1. Fractal lacunarity of trabecular bone and magnetic resonance imaging: New perspectives for osteoporotic fracture risk assessment.

    Science.gov (United States)

    Zaia, Annamaria

    2015-03-18

    fractal analysis as a promising approach to quantify morpho-functional changes in both aging and pathology. In this particular context, fractal lacunarity seems to be the proper tool to characterize TBA texture as it is able to describe both discontinuity of bone network and sizes of bone marrow spaces, whose changes are an index of bone fracture risk. In this paper, an original method of MRI texture analysis, based on TBA fractal lacunarity is described and discussed in the light of new perspectives for early diagnosis of osteoporotic fractures.

  2. Organ and tissue level properties are more sensitive to age than osteocyte lacunar characteristics in rat cortical bone

    DEFF Research Database (Denmark)

    Wittig, Nina; Bach-Gansmo, Fiona Linnea; Birkbak, Mie Elholm;

    2016-01-01

    of bone on the organ and tissue level, whereas features on the nano- and micrometer scale are much less explored. We investigated the age-related development of organ and tissue level bone properties such as bone volume, bone mineral density, and load to fracture and correlated these with osteocyte...... orientation with animal age. Hence, the evolution of organ and tissue level properties with age in rat cortical bone is not accompanied by related changes in osteocyte lacunar properties. This suggests that bone microstructure and bone matrix material properties and not the geometric properties...

  3. The correlation of the thalamic lesions on MRI with cerebral cortical blood flow in patients with lacunar infarction

    Energy Technology Data Exchange (ETDEWEB)

    Nabatame, Hidehiko; Nakamura, Kazuo; Matsuda, Minoru; Fujimoto, Naoki [Shiga Medical Center, Moriyama (Japan); Fukuyama, Hidenao

    1995-07-01

    We performed MRI and measured cerebral blood flow (CBF) using {sup 123}I-IMP SPECT microsphere model in twenty three right-handed patients with lacunar infarction. Twelve of 23 patients showed chronic deterioration of dysarthria and gait disturbance. The mental function of the patients was evaluated by the Mini-Mental State (MMS) examination. The area of high intensity on T2-weighted images was quantitatively analyzed in the cerebral white matter (WM), lenticular nucleus (LN) and thalamus (THA). The score of MMS was positively correlated with the local CBF in the bilateral frontal, parietal, temporal and occipital cortices (p<0.05). Also, the area of high intensity in the left THA showed a significant negative correlation with local CBF of the bilateral frontal, parietal, temporal and occipital cortices (p<0.001). The high intensity areas of the bilateral LN, right WM and right THA had a significant but weaker negative correlation with local CBF of some cortices. These findings suggest that thalamic lesions on the dominant side play an important role in the reduction of cortical blood flow and the deterioration of mental functions in patients with lacunar infarction. (author).

  4. The use of fractal dimension and lacunarity in the characterization of mast cell degranulation in rainbow trout (Onchorhynchus mykiss).

    Science.gov (United States)

    Manera, M; Dezfuli, B S; Borreca, C; Giari, L

    2014-11-01

    Fractal analysis is a reliable method for describing, summarizing object complexity and heterogeneity and has been widely used in biology and medicine to deal with scale, size and shape management problems. The aim of present survey was to use fractal analysis as a complexity measure to characterize mast cells (MCs) degranulation in a rainbow trout ex vivo model (isolated organ bath). Compound 48/80, a condensation product of N-methyl-p-methoxyphenethylamine with formaldehyde, was adopted as MCs degranulation agent in trout intestinal strips. Fractal dimension (D), as a measure of complexity, 'roughness' and lacunarity (λ), as a measure of rotational and translational invariance, heterogeneity, in other words, of the texture, were compared in MCs images taken from intestinal strips before and after compound 48/80 addition to evaluate if and how they were affected by degranulation. Such measures were also adopted to evaluate their discrimination efficacy between compound 48/80 degranulated group and not degranulated group and the results were compared with previously reported data obtained with conventional texture analysis (image histogram, run-length matrix, co-occurrence matrix, autoregressive model, wavelet transform) on the same experimental material. Outlines, skeletons and original greyscale images were fractal analysed to evaluate possible significant differences in the measures values according to the analysed feature. In particular, and considering outline and skeleton as analysed features, fractal dimensions from compound 48/80 treated intestinal strips were significantly higher than the corresponding untreated ones (paired t and Wilcoxon test, p fractal dimension and lacunarity values registered according to the analysed feature (greyscale obtained values were, on average, lower than those obtained from outlines and skeletons; General Linear Model, p Fractal analysis proved to be a reliable and objective method for the characterization of MCs

  5. The Quantitative Criteria Based on the Fractal Dimensions, Entropy and Lacunarity for the Spatial Distribution of Cancer Cell Nuclei Enable Identification of Low or High Aggressive Prostate Carcinomas

    Directory of Open Access Journals (Sweden)

    Przemyslaw eWaliszewski

    2016-02-01

    Full Text Available Background: Tumor grading, PSA concentration, and stage determine a risk of prostate cancer patients with accuracy of about 70%. An approach based on the fractal geometrical model was proposed to eliminate subjectivity from the evaluation of tumor aggressiveness and to improve the prediction. This study was undertaken to validate classes of equivalence for the spatial distribution of cancer cell nuclei in a larger, independent set of prostate carcinomas.Methods: The global fractal capacity D0, information D1 and correlation D2 dimension, the local fractal dimension (LFD and the local connected fractal dimension (LCFD, Shannon entropy H and lacunarity were measured using computer algorithms in digitalized images of both the reference set (n = 60 and the test set (n = 208 of prostate carcinomas.Results: Prostate carcinomas were re-stratified into seven classes of equivalence. The cut-off D0 values 1.5450, 1.5820, 1.6270, 1.6490, 1.6980, 1.7640 defined the classes from C1 to C7, respectively. The other measures but the D1 failed to define the same classes of equivalence. The pairs (D0, LFD, (D0, H, (D0, , (D1, LFD, (D1, H, (D1,  characterized the spatial distribution of cancer cell nuclei in each class. The co-application of those measures enabled the subordination of prostate carcinomas to one out of three clusters associated with different tumor aggressiveness. For D0 0.8, the class C1 or C2 contains low complexity low aggressive carcinomas exclusively. For D0 > 1.6980, LFD > 1.7644, LCFD > 1.7051, H > 0.9, and < 0.7, the class C6 or C7 contains high complexity high aggressive carcinomas. Conclusions: The cut-off D0 values defining the classes of equivalence were validated in this study. The cluster analysis suggested that the number of the subjective Gleason grades and the number of the objective classes of equivalence could be decreased from seven to three without a loss of clinically relevant information. Two novel quantitative

  6. MRI and CT for diagnosis of early lacunar infarction%MRI和CT两种不同影像学检查方法对早期腔隙性脑梗塞的临床诊断价值分析

    Institute of Scientific and Technical Information of China (English)

    张艳平

    2016-01-01

    Objective To investigate the clinical diagnostic value of MRI and CT in early lacunar infarction.Methods Clinical data of 326 cases of early lacunar infarction underwent CT,MRI examination in our hospital from March 2012 to June 2015 was retrospectively analyzed.Analyzed the diagnosis of all patients by CT and MRI,compared lesion detection rate of two methods,satisfaction on examination time and cost.Results The study reviewed 326 cases of early lacunar infarction,excluding 7 cases on whose image views of experts were not consistent.In other 319 cases,268 lesions were found after plain CT scan,with lesion size about 0.5-1 cm;472 lesions were found after MRI examination,whose size were mostly less than 0.5 cm;there was statistically significant difference between two examination methods (P<0.05).In 319 cases,231 cases were quite satisfied with MRI,with the satisfaction degree of 72.4%;235 cases were quite satisfied with CT,with the satisfaction degree of 73.7%;there was no statistically significant difference between two examination methods (P>0.05).Conclusions In clinical diagnosis of early lacunar infarction patients,MRI is more sensitive than CT,without radiation,with a higher safety factor.But the satisfaction degree on CT of 319 cases is slightly higher than that on MRI,in addition to MRI taking more than ten minutes,some heart and lung failure patients can not tolerate MRI,the main factor is that cost of MRI is much higher than that of CT,showing low-cost and high detection rate account for a large proportion in the heart of patients.Enhancing the sensitivity of CT and reducing the cost of MRI are the next focus of our work.%目的 探讨MRI和CT两种不同影像学对早期腔隙性脑梗塞的临床诊断价值.方法 回顾分析我院2012年3月至2015年6月收治已确诊早期腔隙性脑梗塞并均已经行CT、MRI检查的患者共326例,分析所有患者CT及MRI的诊断结果,对比两种检查方式的病灶检出率,比较患者

  7. Effect of observational holes and borders on lacunarity and fractality measurements in a galaxy catalogue

    CERN Document Server

    García-Farieta, Jorge E

    2016-01-01

    Cosmological observations reveal that the Universe contains a hierarchy of galaxy clustering with a transition to homogeneity on large scales according to the $\\Lambda$CDM model. Some observational estimates suggest that the Universe behaves as a multifractal object, where galactic clustering is based on generalisation of the dimension in metric spaces. From this point of view, we study the spatial distribution of points by simulating galaxies on large scales in the Universe with samples from the Sloan Digital Sky Survey (SDSS), including observational holes in the masks. We build homogeneous samples following the radial selection function using the "shuffle" method for a main sample of $3,273,548$ points limited to the redshift range $0.0020$ and percentages of holes near $40\\%$, $r_H$ is displaced on scales on the order of $120~Mpc/h$. Hole percentages between $10\\%$ and $30\\%$ show an $r_H$ of $70-90~Mpc/h$, and for percentages below $10\\%$, $r_H$ decreases to become equal to the $r_H$ value of the SDSS-BO...

  8. Free radical scavenger, edaravone, reduces the lesion size of lacunar infarction in human brain ischemic stroke

    Science.gov (United States)

    2011-01-01

    Background Although free radicals have been reported to play a role in the expansion of ischemic brain lesions, the effect of free radical scavengers is still under debate. In this study, the temporal profile of ischemic stroke lesion sizes was assessed for more than one year to evaluate the effect of edaravone which might reduce ischemic damage. Methods We sequentially enrolled acute ischemic stroke patients, who admitted between April 2003 and March 2004, into the edaravone(-) group (n = 83) and, who admitted between April 2004 and March 2005, into the edaravone(+) group (n = 93). Because, edaravone has been used as the standard treatment after April 2004 in our hospital. To assess the temporal profile of the stroke lesion size, the ratio of the area [T2-weighted magnetic resonance images (T2WI)/iffusion-weighted magnetic resonance images (DWI)] were calculated. Observations on T2WI were continued beyond one year, and observational times were classified into subacute (1-2 months after the onset), early chronic (3-6 month), late chronic (7-12 months) and old (≥13 months) stages. Neurological deficits were assessed by the National Institutes of Health Stroke Scale upon admission and at discharge and by the modified Rankin Scale at 1 year following stroke onset. Results Stroke lesion size was significantly attenuated in the edaravone(+) group compared with the edaravone(-) group in the period of early and late chronic observational stages. However, this reduction in lesion size was significant within a year and only for the small-vessel occlusion stroke patients treated with edaravone. Moreover, patients with small-vessel occlusion strokes that were treated with edaravone showed significant neurological improvement during their hospital stay, although there were no significant differences in outcome one year after the stroke. Conclusion Edaravone treatment reduced the volume of the infarct and improved neurological deficits during the subacute period, especially

  9. 老年人执行功能障碍与腔隙性脑梗死的关系%Relations between Executive Dysfunction and Lacunar Infarction in Senior Patients

    Institute of Scientific and Technical Information of China (English)

    王玲; 吴楠; 王健; 王中平; 焦清海

    2011-01-01

    目的 探讨老年腔隙性脑梗死患者执行功能损害状况以及二者关系.方法 对39例老年志愿者进行头颅MRI、CT检查,按照有无腔隙性脑梗死分为梗死组14例和无梗死组25例,运用神经心理学测试方法评估两组执行功能损害状况,分析腔隙性脑梗死灶的数量和执行功能损害的关系.结果 腔隙性梗死组执行功能测验中额叶功能评定量表(FAB)(8.73±3.47)分,执行性画钟作业(CLOX)(8.73±3.47)分,词语流畅性测验(RVR)(29.75±12.17)分,均低于无梗死组的(11.66±2.37)分、(12.15±2.36)分及(38.24±8.93)分(P<0.05).单因素回归分析显示,腔隙性脑梗死灶的数目和3项执行功能测验均呈明显的负性关系,FAB评分r2=0.9420,P<0.05;CLOX评分r2=0.8715,P<0.05;RVR评分r2=0.9231,P<0.05.结论 老年腔隙性脑梗死会对执行功能产生影响,腔隙性脑梗死灶的数量与执行功能的下降显著相关.%Objective To investigate the situation of executive function in patients with lacunar infarction and the relations between the executive dysfunction and lacunar infarctions. Methods 39 senior volunteers were divided into lacunar infarction group (n = 14) and non- lacunar infarction group (n =25) after undergoing head CT and MRI examination. The executive function in the two groups was compared by neuropsychological tests, and the relations between the number of lacunar infarction and the damage of executive function were analyzed. Results The scores of executive function tests in lacunar infarction group were 8.73 ±3.47 ( frontal assessment battery, FAB ), 8. 73 ± 3.47 ( executive clock-drawing task, CLOX) and 29.75 ± 12. 17 ( vocabulary test, RV R) respectively, but in non-lacunar infarction group they were 11.66 ± 2.37,12.15 ± 2.36,and 38.24 ± 8.93 respectively, and the differences were significant (P < 0. 05). The one-factor regressive analysis showed that the number of lacunar infarction was negatively related to the three

  10. Correlation analysis between the carotid artery ather osclerosis severity of patients with lacunar infarct and the level of serum uric acid, high-sensitivity C-reactive protein

    Directory of Open Access Journals (Sweden)

    WANG Shu

    2013-01-01

    Full Text Available Background Nowadays, clinical practice shows that the number of patients with cerebral infarction increases year by year in young and middle-aged adults with unclear causes. This paper aims to investigate the correlation between the level of serum uric acid (UA, high-sensitivity C-reactive protein (hsCRP and the degree of carotid atherosclerosis by detecting the level of UA, hsCRP and carotid intima-media thickness (IMT in young and middle-aged patients with lacunar infarct. Methods By using Holland Philips HT-11 color Doppler ultrasonic diagnostic apparatus with linear type probe and 7.50MHz frequency, IMT of end-diastolic distal and bifurcation of arteria carotis communis and proximal internal carotid artery were measured respectively on 186 patients with definitely diagnosed lacunar infarct. As a result, average values were taken as the IMT values. IMT < 1.00 mm was regarded as negative result and 1.00 mm ≤IMT < 1.20 mm was thickening of carotid artery intima. Carotid artery plaque formation was regarded with echo structure existing in the lumen or abnormal blood flow deficits into the lumen, or local IMT ≥1.20 mm at vertical and horizontal scan. At the same time, the levels of UA and hsCRP were detected, and correlation analysis was made between them and IMT. Results The values of UA, hsCRP and IMT in the case group were higher than that in the control group (P = 0.000. The differences among the case subgroups including IMT thickening group, plaque formation group and IMT normal group were statistically significant (P < 0.01, for all. There was linear correlation between the levels of UA, hsCRP and IMT ( r = 0.923, P = 0.000; r = 0.955, P = 0.008. Conclusion UA and hsCRP involve in the formation of atherosclerosis plaque and play an important role in the first-onset lacunar infarct patients without hypertension and other risk factors.

  11. 血管紧张素转换酶基因多态性与高血压病早期腔隙性脑梗死的关系%Relationships between angiotensin-converting enzyme gene polymorphism and lacunar infarction in early stage of essential hypertension

    Institute of Scientific and Technical Information of China (English)

    徐岩; 毛建华

    2003-01-01

    AIM:To investigate the relationships between angiotensin converting enzyme gene polymorphism and lacunar infarction in patients with essential hypertension.METHODS:Polymerase chain reaction(PCR) was used to determine the genotypes for an insertion/deletion polymorphism of 287 pb fragment of ACE gene in 50 healthy persons,50 patients with simple essential hypertension and 30 patients with essential hypertension and lacunar infarction.RESULTS:There was no significant difference of genotype and allele between healthy persons and patients with simple essential hypertension;but there was significant difference of D allele and DD genotype of ACE gene between esential hypertensive patients with lacunar infarction and patients with simple essential hypertension and healthy persons.CONCLUSION:There is a significant relation between ACE gene polymorphism and essential hypertensive patients with lacunar infarction.

  12. Correlation between lacunar infarction and glomeruar filtration rate in elderly patients%老年患者腔隙性脑梗死与肾小球滤过率的关系

    Institute of Scientific and Technical Information of China (English)

    李娜; 李辉; 胡新国; 程玲; 吴卫平; 管维平

    2012-01-01

    [Objective To study the correlation between lacunar infarction(LI) and glomeruar filtration rate(GFR) in elderly patients. Methods One hundred and twenty-seven MRI-confirmed male LI patients aged ≥80 years were divided into single lesion group(n = 35) and multiple lesion group(w = 92) according to the number of lesions. Following clinical data were collected,including 24 hdynamic blood pressure,age,BMI,and history of smoking,alcohol dinking,hypertension,diabetes mellitus,heart disease,and serum creatinine(SCr) and blood-lipid levels. GFR was estimated according to the Cockcroft-Gault equation. Correlation between GFR and LI level was analyzed by multiple logistic regression analysis. Results The SCr level was significantly higher while the GFR was significantly lower in multiple lesion group with its GFR <60 ml/(min ? 1. 73 m2) than in single lesion group(P<0. 05). Logistic regression analysis showed that the low GFR was closely correlated with the LI level, and the lower the GFR was, the higher the incidence of LI was (OR = 2. 14,P = 0. Oil). Conclusion Low GFR is an important risk factor for LI in elderly patients and can thus be used as a warning factor for LI.%目的 探讨老年(≥80岁)患者腔隙性脑梗死(lacunar infarction,LI)与肾小球滤过率(glomeruar filtration rate,GFR)的相关性.方法 选择经头颅MRI证实的老年男性LI患者127例,根据病灶数目分为单发组35例和多发组92例.采集患者的24 h动态血压、年龄、体重指数、吸烟、饮酒、血清肌酐、高血压、血脂、糖尿病、心脏病等临床资料,采用Cockcroft-Gault公式估算GFR.采用多因素logistic回归分析LI与GFR的相关性.结果 与单发组比较,多发组患者血清肌酐、GFR<60 ml/(min·1.73 m2)明显升高(P<0.01),GFR明显降低(P<0.05).logistic回归分析显示,GFR降低与LI的发生密切相关(P<0.05),GFR降低越严重,LI发生率越高(OR=2.14,P=0.011).结论 GFR降低可能为老年LI的重要危险因素,或可成为LI的预警因素.

  13. Hyperpolarized {sup 3}helium magnetic resonance ventilation imaging of the lung in cystic fibrosis: comparison with high resolution CT and spirometry

    Energy Technology Data Exchange (ETDEWEB)

    McMahon, Colm J.; Dodd, Jonathan D.; Skehan, Stephen J.; Masterson, James B. [St. Vincent' s University Hospital, Department of Radiology, Dublin (Ireland); Hill, Catherine; Woodhouse, Neil; Wild, Jim M.; Fichele, Stan [Royal Hallamshire Hospital, The Unit of Academic Radiology, University of Sheffield, Sheffield (United Kingdom); Gallagher, Charles G. [St. Vincent' s University Hospital, Department of National Referral Centre for Adult Cystic Fibrosis, Dublin (Ireland); Beek, Edwin J.R. van [Royal Hallamshire Hospital, The Unit of Academic Radiology, University of Sheffield, Sheffield (United Kingdom); University of Iowa, Department of Radiology, Carver College of Medicine, Iowa City, IA (United States)

    2006-11-15

    The purpose of this study was to compare hyperpolarized {sup 3}helium magnetic resonance imaging ({sup 3}He MRI) of the lungs in adults with cystic fibrosis (CF) with high-resolution computed tomography (HRCT) and spirometry. Eight patients with stable CF prospectively underwent {sup 3}He MRI, HRCT, and spirometry within 1 week. Three-dimensional (3D) gradient-echo sequence was used during an 18-s breath-hold following inhalation of hyperpolarized {sup 3}He. Each lung was divided into six zones; {sup 3}He MRI was scored as percentage ventilation per lung zone. HRCT was scored using a modified Bhalla scoring system. Univariate (Spearman rank) and multivariate correlations were performed between {sup 3}He MRI, HRCT, and spirometry. Results are expressed as mean{+-}SD (range). Spirometry is expressed as percent predicted. There were four men and four women, mean age=31.9{+-}9 (20-46). Mean forced expiratory volume in 1 s (FEV){sub 1}=52%{+-}29 (27-93). Mean {sup 3}He MRI score=74%{+-}25 (55-100). Mean HRCT score=48.8{+-}24 (13.5-83). The correlation between {sup 3}He MRI and HRCT was strong (R={+-}0.89, p<0.001). Bronchiectasis was the only independent predictor of {sup 3}He MRI; {sup 3}He MRI correlated better with FEV{sub 1} and forced vital capacity (FVC) (R=0.86 and 0.93, p<0.01, respectively) than HRCT (R={+-}0.72 and {+-}0.81, p<0.05, respectively). This study showed that {sup 3}He MRI correlates strongly with structural HRCT abnormalities and is a stronger correlate of spirometry than HRCT in CF. (orig.)

  14. Iris Feature Extraction Algorithm Using Vertically Expanded Blanket Dimension and Lacunarity%基于毯子维和缺项的虹膜特征提取算法

    Institute of Scientific and Technical Information of China (English)

    刘凯; 周卫东; 王玉

    2011-01-01

    Iris feature extraction is important in iris recognition. An iris feature extraction algorithm is proposed by using combination of blanket dimension and lacunarity. Because Human iris texture is characterized by fractal geometry due to its rich self-similarity and abundant variation, vertically expanded blanket dimension is employed to represent iris texture variation and radial pattern at different resolution levels. Lacunarity is introduced to extract iris features that have different texture and fractal patterns but have same fractal dimension value. The combination of blanket dimension and lacunarity in iris feature extraction can embody the minute change of texture information comprehensively, and improve the capacity of iris classification. The experimental results on the CASIA-IrisV3-Interval iris database show that the combination of blanket dimension and lacunarity can extract iris textural features accurately and effectively, and high performance for iris recognition is achieved by using those features.%虹膜特征提取是虹膜识别的一个关键环节.文中提出一种毯子维和缺项相结合的虹膜特征提取算法.利用虹膜纹理的自相似和丰富的变化细节所具有的分形几何特性,采用纵向扩展毯子维表达不同分辨能力下虹膜纹理的变化及其辐射排列特点.通过引入缺项进一步提取不同纹理和分形表现却具有相同分形维数的虹膜特征.两者的结合能够更加全面地反映虹膜纹理的细腻变化.将归一化虹膜图像灰度值的毯子维及缺项用于虹膜分类,提高对虹膜的分类能力.针对CASIA-IrisV3-Interval数据库的仿真结果表明,纵向扩展毯子维结合缺项能够有效、快速提取虹膜的纹理信息,所获得的特征具有高的虹膜识别性能.

  15. Contribution to the determination of the double angular and energy differential neutron albedo. Application to the propagation in lacunar medium; Contribution a la determination de l'albedo doublement differentiel en angle et en energie des neutrons. Application a la propagation dans les milieux lacunaires

    Energy Technology Data Exchange (ETDEWEB)

    Litaize, O

    2000-07-01

    The goal of this thesis is to study the neutron propagation by reflection from lacunar medium interfaces. The most efficient method to calculate this type of propagation is to use the concept of albedo. Actual version of NARCISSE code uses a simple formulation of angular differential albedos and so, can only treat single reflections. Multiple reflections treatment needs the knowledge of neutron spectrum after reflection. This energetic information is contained in double angular and energy differential albedos. The first step of this study consists to generate these albedos for various materials. Several methods have been tested and the Monte Carlo method was retained. A new estimator has been developed and validated in the Mote Carlo transport code TRIPOLI-4. It computes, during the simulation of the neutron history, the angular and energy reflection probability at each collision site. The second step consists to generate an interpolation scheme and albedo libraries for various materials. A new version of NARCISSE was developed to use these libraries and the interpolation module. Spectrum and dose rates comparisons were made between codes to validate these albedos. The neutron propagation by multiple reflections can be studied now, by using this new version of Narcisse. (author)

  16. CT对腔隙性脑梗死患者近期预后风险的评估%The Risk of Short-term Prognosis Evaluation Values of CT for the Patients with Lacunar Infarction

    Institute of Scientific and Technical Information of China (English)

    刘东顺; 张敏丽; 李翠乔; 司翠权

    2015-01-01

    目的:探讨CT对腔隙性脑梗死患者近期预后风险的评估价值.方法:选取2011年6月-2014年8月笔者所在医院收治的腔隙性脑梗死患者80例,都进行CT检测,同时选择PRR比率和NIHSS评分进行近期预后风险评估.结果:腔隙性脑梗死患者的CT主要表现为形态卵圆形,病灶内部密度大,伴随有豆状核钙化;同时梗死区的CBF和CBV值都明显少于缺血半暗带区,而MTT值明显高于缺血半暗带区(P<0.05).80例患者的PRR比率为(67.33±2.19)%,NIHSS评分为(34.09±12.44)分,Pearson分析显示CBF和CBV值与PRR比率和NIHSS评分存在明显负相关(P<0.05),而MTT值与PRR比率和NIHSS评分存在明显正相关(P<0.05).结论:腔隙性脑梗死在CT灌注参数上有很好的特异性表现,同时对于近期预后风险有很好的指导判定作用,值得推广应用.%Objective:To investigate the risk of short-term prognosis evaluation values of CT for the patients with lacunar infarction. Method:80 lacunar infarction patients which were admitted to our hospital from June 2011 to August 2014 were selected,all the patients were performed CT detection,and the PRR rates and NIHSS scores for the short-term prognosis risk assessment were choosed.Result:CT attenuation mainly for patients with lacunar infarction were showed oval shape,large lesions internal density,accompanied lenticular nucleus calcification;and the CBF and CBV values in the infarct zone were significantly less than the ischemic penumbra,and MTT were significantly higher than the ischemic penumbra(P<0.05).80 patients of the PRR ratios were (67.33±2.19)%,NIHSS scores were 34.09±12.44 points,Pearson analysis showed that CBF and CBV values were negative correlated to the PRR ratio and NIHSS scores(P<0.05),while the values of MTT values were significant positive correlated to the PRR ratio and NIHSS scores(P<0.05).Conclusion:Lacunar infarction on CT perfusion parameters has good specific performance,while has risk of short

  17. Cerebral Small Vessel Disease and Motoric Cognitive Risk Syndrome: Results from the Kerala-Einstein Study

    Science.gov (United States)

    Wang, Nan; Allali, Gilles; Kesavadas, Chandrasekharan; Noone, Mohan L.; Pradeep, Vayyattu G.; Blumen, Helena M.; Verghese, Joe

    2017-01-01

    Background The contribution of cerebral small vessel disease to cognitive decline, especially in non-Caucasian populations, is not well established. Objective We examined the relationship between cerebral small vessel disease and motoric cognitive risk syndrome (MCR), a recently described pre-dementia syndrome, in Indian seniors. Methods 139 participants (mean age 66.6 ± 5.4 y, 33.1% female) participating in the Kerala-Einstein study in Southern India were examined in a cross-sectional study. The presence of cerebral small vessel disease (lacunar infarcts and cerebral microbleeds (CMB)) and white matter hyperintensities on MRI was ascertained by raters blinded to clinical information. MCR was defined by the presence of cognitive complaints and slow gait in older adults without dementia or mobility disability. Results Thirty-eight (27.3%) participants met MCR criteria. The overall prevalence of lacunar infarcts and CMB was 49.6% and 9.4%, respectively. Lacunar infarcts in the frontal lobe, but no other brain regions, were associated with MCR even after adjusting for vascular risk factors and presence of white matter hyperintensities (adjusted Odds Ratio (aOR): 4.67, 95% CI: 1.69–12.94). Frontal lacunar infarcts were associated with slow gait (aOR: 3.98, 95% CI: 1.46–10.79) and poor performance on memory test (β: −1.24, 95% CI: −2.42 to −0.05), but not with cognitive complaints or non-memory tests. No association of CMB was found with MCR, individual MCR criterion or cognitive tests. Conclusions Frontal lacunar infarcts are associated with MCR in Indian seniors, perhaps, by contributing to slow gait and poor memory function. PMID:26757037

  18. Analysis of the intracranial lesions, cerebrovascular conditions and lacunar infarction in patients with migraine%偏头痛与脑血管发育异常、脑白质变性、脑腔梗关系分析

    Institute of Scientific and Technical Information of China (English)

    赵轶; 席刚明

    2014-01-01

    目的:观察偏头痛患者脑血管情况及颅内病变情况。方法:以住院偏头痛患者为研究对象、同一时期无偏头痛患者为对照,进行神经影像学比较。结果:58例偏头痛患者中,有脑腔梗病灶19例(32.76%),有脑白质变性17例(29.31%),有脑血管异常37例(63.79%)。61例对照组中有脑腔梗病灶9例(14.75%),有脑白质变性5例(8.20%),有脑血管异常13例(21.31%)。2组比较差异均有统计学意义(P<0.05)。结论:偏头痛与脑白质病变、脑腔梗有关,血管因素可能参与偏头痛的发作。%Objective:To obtain the intracranial lesions and cerebrovascular conditions in patients with migraine.Methods:Patient with migraine collected from the hospitalized were compared with patients with non-migraine in their neurimaging findings.Results:Among 58 patients with migraine, 19 had a or more lacunar infarctions;17 had white matter lesions and 37 had cerebrovascular abnormalities, while 61 patients with non-migraine had 9 lacunar infarctions, 5 white matter lesions and 13 cerebrovascular abnormalities. They were all signiifcantly different(P<0.05).Conclusion:Migraine was associated with the white matter lesions and lacunar infarction, while vascular factors may be involved in the migraine.

  19. 伴基底节钙化的婴幼儿外伤后腔隙性脑梗塞%Pusttraumatic cerebral lacunar infarction in infants with basal ganglia calcifications

    Institute of Scientific and Technical Information of China (English)

    金惠明; 孙莲萍; 鲍南

    2001-01-01

    Objective To explore the pathologic mechanism and treatment of posttraumatic cerebral lacunar infarction in infants with basal ganglia calcifications. Methods The symptoms, radiation demonstrations, treatments and prognosis in 20 infants undergoing cerebral infarction following minor cerebral trauma were reviewed retrospectively. Results Posttraumatic cerebral infarctions all occurred in only one side of basal ganglia. It leads to acute hemiplegia in the patients, but no changes of consciousness and no signs of intracranial hypertension were noted. CT scan showed punctate calcification in bilateral basal ganglia and lacunar infarction just beside them. After treatment the infants recovered well within 3months. Conclusions The occurrence of posttraumatic cerebral lacunar infarction is closely associated with basal ganglia calcification, but its mechanism is not clear. It needs to be differentiated from cerebral toxoplasmosis and cytomegalic inclusion disease.%目的探讨伴有基底节钙化的婴幼儿外伤后腔隙性脑梗塞的发病机理和治疗效果。方法总结20例婴幼儿较轻微头颅外伤后发生脑梗塞的症状、影像学表现、治疗效果及预后。结果婴幼儿外伤后脑梗塞均发生于一侧基底节区。l临床表现为不同程度的一侧急性偏瘫、无意识改变及颅内高压症状。CT扫描发现双侧基底节区存在细小点状钙化,腔隙性脑梗塞灶毗邻钙化点。经治疗预后好,随访3个月全部康复。结论婴幼儿外伤后腔隙性脑梗塞的发生与基底节钙化关系密切。但发病机理及基底节钙化的生理过程尚有待探究。本病诊断需与脑弓形虫病及巨细胞包涵体病等相鉴别。

  20. Mechanisms of cognitive impairment in cerebral small vessel disease: multimodal MRI results from the St George's cognition and neuroimaging in stroke (SCANS study.

    Directory of Open Access Journals (Sweden)

    Andrew J Lawrence

    Full Text Available Cerebral small vessel disease (SVD is a common cause of vascular cognitive impairment. A number of disease features can be assessed on MRI including lacunar infarcts, T2 lesion volume, brain atrophy, and cerebral microbleeds. In addition, diffusion tensor imaging (DTI is sensitive to disruption of white matter ultrastructure, and recently it has been suggested that additional information on the pattern of damage may be obtained from axial diffusivity, a proposed marker of axonal damage, and radial diffusivity, an indicator of demyelination. We determined the contribution of these whole brain MRI markers to cognitive impairment in SVD. Consecutive patients with lacunar stroke and confluent leukoaraiosis were recruited into the ongoing SCANS study of cognitive impairment in SVD (n = 115, and underwent neuropsychological assessment and multimodal MRI. SVD subjects displayed poor performance on tests of executive function and processing speed. In the SVD group brain volume was lower, white matter hyperintensity volume higher and all diffusion characteristics differed significantly from control subjects (n = 50. On multi-predictor analysis independent predictors of executive function in SVD were lacunar infarct count and diffusivity of normal appearing white matter on DTI. Independent predictors of processing speed were lacunar infarct count and brain atrophy. Radial diffusivity was a stronger DTI predictor than axial diffusivity, suggesting ischaemic demyelination, seen neuropathologically in SVD, may be an important predictor of cognitive impairment in SVD. Our study provides information on the mechanism of cognitive impairment in SVD.

  1. 维生素B12与腔隙性脑梗塞后抑郁的关联研究%Association of Vitamin B12 with Depression after Lacunar Stroke

    Institute of Scientific and Technical Information of China (English)

    李中春; 呙登俊; 江霞

    2013-01-01

    OBJECTIVE To explore the association of serum vitamin B12 with depression after lacunar stroke.METHODS Between June 2009 and June 2012,829 patients with lacunar stroke,according to Hamilton depression scale score,were divided into two groups:group with depression and group without depression.The concentration of serum vitamin B 12 and the ratio of vitamin B12 deficiency were compared.The relationship between Hamilton depression scale score and the concentration of serum vitamin B 12 in the group with depression was analyzed by the curve-fitting method.RESULTS The group without depression contained 750 cases and the mean concentration of serum vitamin B12 of this group was (172.5±20.4)pmol·L-1.There were 212 cases in the group without depression which were considered as vitamin B 12 deficiency.The group with depression contained 79 cases and the mean concentration of serum vitamin B12 of this group was (139.1±18.2)pmol·L-1.There were 53 cases in the group with depression which were considered as vitamin B12 deficiency.There were significant differences in the concentration of serum vitamin B 12 and the ratio of vitamin B 12 deficiency(P<0.000 1).Inverse curve reflected the relationship between Hamilton depression scale score and the concentration of serum vitamin B 12 in the group with depression.CONCLUSION Depression after lacunar stroke is related to vitamin B12 deficiency.%目的 探讨血清维生素B12与腔隙性脑梗塞后抑郁之间关系.方法 2009年6月—2012年6月腔隙性脑梗塞患者共829例,使用汉密尔顿抑郁量表将患者分为两组:无抑郁组和抑郁组,比较两组间血清维生素B12浓度和维生素B12缺乏者的比例.在抑郁组内对汉密尔顿抑郁量表评分和血清维生素B12浓度进行曲线拟合.结果 无抑郁组患者750例,血清维生素B12平均浓度为(172.5±20.4)pmol·L-1,其中维生素B12缺乏者212例.抑郁组79例,血清维生素B12平均浓度为(139.1± 18.2)pmol·L-1,

  2. 长春西汀联合依达拉奉治疗急性腔隙性脑梗死临床观察%Clinical observation of vinpocetine combined with edaravone in the treatment of acute lacunar infarction

    Institute of Scientific and Technical Information of China (English)

    廖纪华; 郑乃清; 唐锦程; 吴新爱

    2015-01-01

    目的:观察长春西汀注射液联合依达拉奉治疗急性腔隙性脑梗死的临床疗效。方法96例急性腔隙性脑梗死患者随机分为观察组和对照组,各48例,两组在治疗相应基础病和常规抗凝、抗血小板聚集治疗基础上,观察组加用长春西汀注射液及依达拉奉进行治疗,对照组加用倍他司汀注射液及血塞通注射液进行治疗,疗程2周。观察两组治疗效果、记录不良反应、评估安全性。治疗前和治疗2周后进行欧洲脑卒中评分(ESS),用积分评判疗效。结果观察组总有效率为93.8%,优于对照组81.3%,差异具有统计学意义(P<0.05)。两组药物无明显不良反应。结论相比使用倍他司汀+血塞通,长春西汀联合依达拉奉治疗急性腔隙性脑梗死疗效确切,安全性好,值得临床推广应用。%Objective To investigate the clinical effect of vinpocetine combined with edaravone in the treatment of acute lacunar infarction.Methods A total of 96 acute lacunar infarction patients were randomly divided into observation group and control group, with 48 cases in each group. On the basis of treatment for background disease, conventional anticoagulation, and anti-platelet aggregation, the observation group received vinpocetine injection combined with edaravone for treatment, and the control group received betahistine injection and Xuesaitong injection for treatment. Treatment lasted for 2 weeks. Curative effects of the two groups were observed, their adverse reactions were recorded and safety was evaluated. The European stroke scale (ESS) was applied before treatment and in 2 weeks after treatment, and their scores were used for effects evaluation.ResultsTotal effective rate of the observation group was 93.8%, which was much better than 81.3% of the control group. The difference had statistical significance (P<0.05). Both groups had no obvious adverse reactions.Conclusion Compared with betahistine + Xuesaitong

  3. P选择素在原发性高血压伴腔隙性脑梗死患者发病机制中的作用%Effect of P-selectin in primary hypertension associated with lacunar infarction

    Institute of Scientific and Technical Information of China (English)

    龚艳春; 郭冀珍; 史桂英; 石学耕; 龚兰生

    2003-01-01

    目的 观察血小板活化的标志-- P-选择素在原发性高血压伴腔隙性脑梗死患者发病机制中的作用. 方法利用 FITC标记的抗 CD42a单抗(鼠 IgG1) ,PE标记的抗 CD62P单抗(鼠 IgG1) ,CY标记的抗 CD45单抗(鼠 IgG1) ,FITC标记的鼠 IgG1同种型对照免疫球蛋白 ,PE标记的鼠 IgG1同种型对照免疫球蛋白,上述单抗分别标记全血中血小板及白细胞的相关抗原;同时利用流式细胞仪,采取全血三色法流式细胞术方法,检测全血血小板上 P-选择素阳性表达:全血标本中分别加入 3种荧光标记的单克隆抗体 FITC -CD42a, PE-62P及 CY- CD45,室温避光反应 20 min, 10g/L多聚甲醛固定 10 min,用 PBS洗 2次,上机分析. 结果原发性高血压伴腔隙性脑梗死患者血小板 P-选择素阳性表达 [( 23.0± 4.0)% ]明显高于原发性高血压无腔隙性脑梗死患者 [( 16.9± 1.8%) ]及正常人组 [(5.2± 0.7)% ],三者之间相比差异有显著性意义( t=137.4,28.4, P< 0.05). 结论 P-选择素在原发性高血压伴腔隙性脑梗死发病中起重要作用, P-选择素与血管渐进损伤有关.%AIM:To detect the effect of P-selectin,the marker of platelet activation in primary hypertension associated with lacunar infarction. METHODS:FITC-labeled antiCD42a monoclonal antibody(mice IgG1),PE labeled antiCD62P monoclonal antibody(mice IgG1),CY labeled antiCD45 monoclonal antibody(mice IgG1),FITC labeled mice IgG1 isotype matched immune globulin,PE labeled mice IgG contrast immunoglobulin were used to label corresponding antigens of platelets and leukocytes in whole blood.At the same time, P-selectin on the platelet was detected by the method of three-color cytometery in whole blood;Three monoclonal antibodies with fluorescence labeled, FITC-CD42a, PE -62P and CY-CD45 were added in whole blood specimen and incubated for 20 min without light and under room temperature,over night.Then specimen was fixed with citromint for 10 min and washed with PBS

  4. Evaluation about Montreal cognitive assessment scale in patients with lacunar infarction%蒙特利尔认知评估量表在腔隙性脑梗死患者中的临床应用观察

    Institute of Scientific and Technical Information of China (English)

    徐心; 吴杨; 胡晓蕾

    2013-01-01

    害的认知领域不同.%Objective To evaluate the application value of Montreal Cognitive Assessment (MoCA)in patients with lacunar infarction (LI),and to explore the relevance of cognitive impairment in different areas and imaging of lesion site in patients with LI.Methods 159 cases were divided into three groups according to the MoCA and MMSE score,the control group with normal cognitive function (MMSE score above the demarcation line and MoCA score ≥ 26 points),the observation group (MMSE score above the demarcation line and the MoCA < 26points),the cognitive dysfunction group(MMSE score below the demarcation line and MoCA < 26 points).The demographic data of all patients,the LI lesion site in head MRI and the MoCA and MMSE score were recorded,the relation between the LI lesion site in head MRI and the MoCA and MMSE score were analysed.The results were calculated with SPSS 17.0.Results (1) The isolation rate of MMSE and MoCA of abnormal cognitive function in patients with LI were 38.36% and 83.01%.The MoCA scores of patients with abnormal MMSE score were also abnormal.In patients with normal MMSE score (accounting for 61.63% of the sample),the MoCA scores were abnormal which accounting for 44.65 % of total study population.(2)The head MRI findings showed that the lesion site of patients with LI occured multiply in frontal lobe,parietal lobe,basal ganglia,the most common,then the thalamus,brain stem and periventricular white matter.(3)The different infarct lesion sites were related to the different field of cognitive impairment(P < 0.05).The damage of the frontal lobe lesions were related to the damage of executive function,visuospatial ability,attention and calculation power,language,abstract force and memory.The damage of parietal lobe lesions were related to the damage of executive function,visuospatial ability damage.The harm of basal ganglia lesions were related to the damage of executive function,memory,calculation and attention damage.The injure of hypothalamic lesions were

  5. CT 与 MRI 对腔隙性梗死的诊断价值分析%Analysis of compared CT with MRI in diagnosis value of lacunar infarction

    Institute of Scientific and Technical Information of China (English)

    严补生

    2015-01-01

    目的:比较C T与M RI对腔隙性梗死的诊断价值。方法选择腔隙性梗死患者40例为研究对象,均于入院3 h内行急诊螺旋CT及MRI检查。以临床诊断为准,观察CT 与MRI对腔隙性梗死病灶数量及部位诊断情况。比较CT 与MRI对发病<24 h、24~72 h、>72 h患者脑内病灶及径线<5 mm、5~10 mm和>10~15 mm病灶检出情况。结果(1)脑梗死病灶分布于额叶6例,顶叶6例,颞叶6例,枕叶4例,基底节区8例,丘脑3例,脑干3例,小脑4例。40例患者中,C T共显示21例患者存在脑梗死病灶,共显示病灶45处。M RI共显示38例患者存在脑梗死病灶,共显示病灶79处。M RI对脑梗死病灶检出率显著高于C T ,差异具有统计学意义( P<0.05)。(2)M RI对<24 h、24~72 h脑梗死病灶的检出率显著高于CT ,差异具有统计学意义(P<0.05)。两者在>72 h病灶的检出中,差异无统计学意义(P>0.05)。(3)其中MRI对径线<5 mm及5~10 mm腔隙性梗死病灶检出率显著高于CT ,差异具有统计学意义(P<0.05)。在病灶径线10~15 mm病灶的检出中,MRI及CT比较差异无统计学意义(P>0.05)。结论在腔隙性梗死的诊断中,MRI较CT更具有优势。%Objective To compare the value of CT and MRI in diagnosis of lacunar infarction.Methods 40 cases with la‐cunar cerebral infarction as the objects ,which were detected by spiral CT and MRI examination within 3 h admitted to our hos‐pital. Lesion number and site of cerebral lacunar infarction by CT and MRI were observed.The onset of cerebral infarction within 24 h ,between 24 h and 72 h ,more than 72 h;and diameter less than 5 mm ,between 5 mm and 10 mm ,between >10 and 15 mm detected by CT and MRI were compared.Results 6 cases of cerebral infarction lesions located in frontal lobe ,6 ca‐ses in parietal lobe ,6 cases in temporal lobe ,4 cases in occipital lobe ,8 cases in basal ganglia

  6. 皮层下动脉硬化性脑病100例临床CT分析%CT and MRI T2WI, and FLAIR and DWI in diagnostic value of cerebral lacunar infarction and its prognosis analysis

    Institute of Scientific and Technical Information of China (English)

    罗青毅; 邹习忠; 冉强; 董志鹏

    2014-01-01

    目的:探讨皮层下动脉硬化性脑病颅脑ct诊断的意义和价值。方法结合我院临床诊断为皮层下动脉硬化性脑病, ct表现为侧脑室周围脑白质脱髓鞘改变的100例病例,按Goto分类法,将侧脑室前角周围脑白质脱髓鞘改变程度不同分为三型的标准,进行临床和影像综合分析。结果按Goto分类法Ⅰ型和Ⅱ型63例,临床表现轻,Ⅲ型37例,症状重,常偏瘫和言语不清,ct表现伴有脑萎缩(96例),腔隙性脑梗死(74例),伴大面积脑梗死(8例)、脑出血(7例)、脑积水和蛛网膜下腔积液(12例)。结论 ct检查对皮层下动脉硬化性脑病的诊断具有重要的价值,对于临床在预防、诊断和治疗皮层下动脉硬化性脑病方面具有重要意义。%Objectiveto explore the value of ct in diagnosis of subcortical arteriosclerotic encephalopathy (sae). Methods100 patients were deifnitely diagnosed as SAE by clinic. CT showed low density of surrounding bilateral ventricle. Demyelinating encephalopathy of frontal horn of bilateral ventricle were divided into three types according to the classiifcation of Goto.Results clinical presentations showed mild in typesⅠ andⅡ in 63 patients, severe symptoms were found in 37 patients, including hemiplegia, and barylalia. ct appeared cerebral atrophy in 96 patients; cerebral lacunar infarction in 74; diffuse cerebral infarction in 8; hemorrhage in 7; and hydrocephalus and hydrops of subarachnoid space in 12.Conclusion ct was very valuable on diagnosis and evaluation of subcortical arteriosclerotic encephalopathy.

  7. Musical hallucinations associated with pontine lacunar lesions.

    Science.gov (United States)

    Serby, Michael J; Hagiwara, Mari; O'Connor, Lisa; Lalwani, Anil K

    2013-01-01

    Three elderly patients experienced musical hallucinations (MH) in the context of hearing loss. In at least two of the cases, the onset was sudden. All three patients had pontine T2/FLAIR hyperintense foci on MR scan after the onset of the MH.

  8. 腔隙性梗死和脑白质病变患者的认知损害%Cognitive impairment in patient with lacunar infarct and white matter lesion

    Institute of Scientific and Technical Information of China (English)

    张永红; 王海峰; 王新; 张莉; 邢成名

    2014-01-01

    目的 探讨腔隙性梗死(lacunar infarct,LI)和脑白质病变(white matter lesion,WML)患者认知损害的特征及其危险因素.方法 纳入年龄65 ~ 75岁的LI和WML住院患者,收集其人口统计学和临床资料.LI和WML通过MRI确诊.采用蒙特利尔认知评估量表(Montreal Cognitive Assessment,MoCA)评价认知功能.采用抑郁自评量表和汉密尔顿焦虑量表排除抑郁和焦虑患者.根据MoCA总分将患者分为认知损害组和认知功能正常组,比较两组人口统计学和临床资料.采用多变量logistic回归分析确定认知损害的独立危险因素.对LI和WML的认知损害特征进行比较.结果 共纳入130例LI或WML患者.其中,92例存在认知损害,38例认知功能正常;85例存在LI,45例存在WML;男性53例,女性77例.单变量分析显示,认知损害组受教育年限[(7.54±4.65)年对(11.29±3.17)年;t=4.286,P=0.001]显著性低于认知正常组,而高血压(54.6%对16.2%;x2=4.477,P=0.018)、高脂血症(53.1%对16.2%;x2=5.263,P =0.044)、糖尿病(46.9%对10.8%;x2=3.827,P=0.017)以及LI(43.8%对21.5%;x2=3.928,P=0.015)和WML(26.9%对7.7%;x2=4.072,P=0.009)的构成比显著性高于认知正常组.多变量logistic回归分析显示,受教育年限[优势比(odds ratio,OR)1.305,95%可信区间(confidence interval,CI)1.104 ~7.975;P=0.001]、糖尿病(OR 1.328,95% CI 1.292~3.422;P=0.015)、高血压(OR1.978,95%CI1.034~5.443;P=0.028)、LI(OR 1.224,95% CI1.004 ~2.007;P=0.013)和WML(OR 1.489,95% CI 1.202~3.778;P=0.010)是认知损害的独立危险因素.WML组MoCA总分[(21.61±5.33)分对(19.19±7.07)分;t=1.841,P=0.038]以及立方体复制[(0.43±0.50)分对(0.31 ±0.47)分;t=1.104,P=0.010]、画钟实验[(2.53 ±0.89)分对(2.04±1.22)分;t=2.229,P=0.008]、字母辨别[(0.85±0.36)分对(0.62±0.50)分;t=2.585 P=0.000]和100连续减7[(2.62±0.79)分对(2.19±1.17)分;=2.113;P=0.001]得分均显著性低于LI组.结论 LI和WML患者均常伴

  9. The correlation of hs-CRP and homocystine level with ESRS in the patents with lacunar infarction%腔隙性脑梗死患者超敏C反应蛋白及同型半胱氨酸水平与ESRS的关系

    Institute of Scientific and Technical Information of China (English)

    石义永; 林传鸿; 余宏; 强锴

    2012-01-01

    目的 探讨腔隙性脑梗死患者超敏C反应蛋白(Hs-CRP)及同型半胱氨酸(Hcy)水平与ESSEN卒中危险评分的关系.方法 125例急性期腔隙性脑梗死患者按ESSEN卒中危险评分将腔隙性脑梗死患者分为低危组(38例)、高危组(71例)、极高危组(16例),进行血浆Hs-CRP和Hcy水平的测定,比较三组间的Hs-CRP和Hcy水平变化及与ESSEN卒中危险评分的关系.结果 ①Hs-CRP水平极高危组显著高于高危组和低危组,(5.00±2.83) ug·ml-1 VS(1.03±1.03)ug·ml-1(P<0.01);(5.00±2.83)ug·ml-1 VS (0.46±0.38) ug·ml-1(P<0.01),高危组显著高于低危组,(1.03±1.03)ug·ml-1 VS (0.46±0.38) ug·ml-1(P<0.05),随着危险因素增加有上升趋势,且Hs-CRP水平同Essen评分呈显著正相关关系(r=0.652,P=0.000).②血浆Hcy水平极高危组与低危、高危组比较差异有统计学意义(P<0.05);且血浆Hcy水平同Essen评分呈正相关关系(r=0.198,p=0.027).③三组年龄、糖尿病患病率、吸烟率、LDL、HDL有统计学意义(P<0.05或<0.01);三组高血压患病率、TC、TG和BMI比较无统计学意义(P>0.05).结论 腔隙性脑梗死患者的Hs-CRP和血浆Hcy水平变化在一定程度上反映患者的危险程度,同Essen评分有良好的相关性.%Objective To investigate the correlation of hs-CRP and homocystine( Hcy )level with Essen Stroke Risk Score( ESRS )in patients with lacunar infarction. Methods According to the ESRS, 125 patients with lacunar infarction were divided into three groups: ow risk group( n = 38 ) ; high risk group ( n =71 ) and very high risk group ( n = 16 ) , plasma Hs -CRP and Hcy levels were measured, the changes of hs-CRP and Hey levels as well as the relationship of hs-CRP and Hcy levels with ESRS were oberved. Results ①)Hs-CRP level in the very high risk group was significantly higher than that in the high risk group and low risk group,( 5. 00 ± 2. 83 ) ug/mL VS (1.03 ± 1.03) ug/mL (P 0. 05 ). Conclusion Hs-CRP and Hcy leves

  10. 伴颈动脉狭窄的腔隙性脑梗死患者介入治疗术后的认知变化%Cognitive changes in patients with lacunar cerebral infarction and carotid stenosis after artery intervention therapy

    Institute of Scientific and Technical Information of China (English)

    赵雄飞; 赵志茹; 徐家萍; 张芮娟; 霍秀利; 王玉; 宋霄; 王拥军

    2016-01-01

    Objective To analyze the cognitive changes and influencing factors in patients with lacunar cerebral infarction after carotid artery intervention therapy. Methods Sixty lacunar cerebral infarction combined with carotid stenosis patients treated with artery intervention therapy (intervention therapy group) and 68 lacunar cerebral infarction without carotid stenosis patients treated with drug therapy (drug therapy group) were selected. The neuropsychological test was completed at entry and 1, 6, 12 months after entry, and the results were compared with 60 healthy controls (control group). The cognitive changes were observed. The neuropsychological test included mini mental state examination (MMSE), Montreal cognitive assessment scale (MoCA) and cognitive field test. Results There were statistical differences in other scores except the Stroop test C section and Wechsler adult intelligence scale (WAIS-RC) picture arrangement subtest at entry in intervention therapy group and drug therapy group compared with control group (P0.05). In intervention therapy group, the MMSE scores, MoCA total score, Rey-Osterrieth complex figure test (ROCFT), auditory verb learning test (AVLT), and the WAIS-RC picture arrangement subtest, verbal fluency test, WAIS-RC digit span backwards subtest of performing function 12 months after entry were significantly better than those at entry, and there were statistical differences (P0.05);the MMSE score, MoCA total score, ROCFT, the immediate recall, long-time delayed recall and short delayed recall of AVLT, WAIS-RC picture arrangement subtest, verbal fluency test, WAIS-RC digit span backwards subtest of performing function and digit span backwards subtest of WAIS-RC 12 months after entry were significantly better than those at entry, and there were statistical differences (P0.05). In patients intervention therapy group, Logistic regression analysis showed that the MoCA score was related with age, hypertension and low education level (P0

  11. Correlation analysis between the carotid artery atherosclerosis severity of patientswith lacunar infarct and the level of serum uric acid, high - sensitivity C - reactiveprotein%血清尿酸、超敏C-反应蛋白与腔隙性脑梗死患者颈动脉粥样硬化程度的相关分析

    Institute of Scientific and Technical Information of China (English)

    王姝

    2013-01-01

    Background Nowadays, clinical practice shows that the number of patients with cerebral infarction increases year by year in young and middle-aged adults with unclear causes. This paper aims to investigate the correlation between the level of serum uric acid (UA), high - sensitivity C-reactive protein (hsCRP) and the degree of carotid atherosclerosis by detecting the level of UA, hsCRP and carotid intima-media thickness (IMT) in young and middle-aged patients with lacunar infarct. Methods By using Holland Philips HT-11 color Doppler ultrasonic diagnostic apparatus with linear type probe and 7.50 MHz frequency, IMT of end - diastolic distal and bifurcation of arteria carotis communis and proximal internal carotid artery were measured respectively on 186 patients with definitely diagnosed lacunar infarct. As a result, average values were taken as the IMT values. IMT < 1.00 mm was regarded as negative result and 1.00 mm ≤ IMT < 1.20 mm was thickening of carotid artery intima. Carotid artery plaque formation was regarded with echo structure existing in the lumen or abnormal blood flow deficits into the lumen, or local IMT ≥ 1.20 mm at vertical and horizontal scan. At the same time, the levels of UA and hsCRP were detected, and correlation analysis was made between them and IMT. Results The values of UA, hsCRP and IMT in the case group were higher than that in the control group (P = 0.000). The differences among the case subgroups including IMT thickening group, plaque formation group and IMT normal group were statistically significant (P<0.01, for all). There was linear correlation between the levels of UA, hsCRP and IMT (r = 0.923, P = 0.000; r = 0.955, P = 0.008). Conclusion UA and hsCRP involve in the formation of atherosclerosis plaque and play an important role in the first - onset lacunar infarct patients without hypertension and other risk factors.%研究背景 中青年脑梗死患者呈逐年增加趋势,病因尚不明确.通过对中青年腔隙性脑梗

  12. Hyperpolarized {sup 3}He magnetic resonance imaging: Preliminary evaluation of phenotyping potential in chronic obstructive pulmonary disease

    Energy Technology Data Exchange (ETDEWEB)

    Mathew, Lindsay, E-mail: lmathew@imaging.robarts.ca [Imaging Research Laboratories, Robarts Research Institute, London (Canada); Department of Medical Biophysics, University of Western Ontario, London (Canada); Kirby, Miranda, E-mail: mkirby@imaging.robarts.ca [Imaging Research Laboratories, Robarts Research Institute, London (Canada); Department of Medical Biophysics, University of Western Ontario, London (Canada); Etemad-Rezai, Roya, E-mail: Roya.EtemadRezai@lhsc.on.ca [Department of Medical Imaging, University of Western Ontario (Canada); Wheatley, Andrew, E-mail: awheat@imaging.robarts.ca [Imaging Research Laboratories, Robarts Research Institute, London (Canada); McCormack, David G., E-mail: David.McCormack@lhsc.on.ca [Imaging Research Laboratories, Robarts Research Institute, London (Canada); Division of Respirology, Department of Medicine, University of Western Ontario, London (Canada); Lawson Health Research Institute, London (Canada); Parraga, Grace, E-mail: gep@imaging.robarts.ca [Imaging Research Laboratories, Robarts Research Institute, London (Canada); Department of Medical Biophysics, University of Western Ontario, London (Canada); Department of Medical Imaging, University of Western Ontario (Canada); Lawson Health Research Institute, London (Canada)

    2011-07-15

    Rationale and objectives: Emphysema and small airway obstruction are the pathological hallmarks of chronic obstructive pulmonary disease (COPD). The aim of this pilot study in a small group of chronic obstructive pulmonary disease (COPD) patients was to quantify hyperpolarized helium-3 ({sup 3}He) magnetic resonance imaging (MRI) functional and structural measurements and to explore the potential role for {sup 3}He MRI in detecting the lung structural and functional COPD phenotypes. Materials and methods: We evaluated 20 ex-smokers with stage I (n = 1), stage II (n = 9) and stage III COPD (n = 10). All subjects underwent same-day plethysmography, spirometry, {sup 1}H MRI and hyperpolarized {sup 3}He MRI at 3.0 T. {sup 3}He ventilation defect percent (VDP) was generated from {sup 3}He static ventilation images and {sup 1}H thoracic images and the {sup 3}He apparent diffusion coefficient (ADC) was derived from diffusion-weighted MRI. Results: Based on the relative contribution of normalized ADC and VDP, there was evidence of a predominant {sup 3}He MRI measurement in seven patients (n = 3 mainly ventilation defects or VDP dominant (VD), n = 4 mainly increased ADC or ADC dominant (AD)). Analysis of variance (ANOVA) showed significantly lower ADC for subjects with predominantly elevated VDP (p = 0.02 compared to subjects with predominantly elevated ADC; p = 0.008 compared to mixed group) and significantly decreased VDP for subjects with predominantly elevated ADC (p = 0.003, compared to mixed group). Conclusion: In this small pilot study, a preliminary analysis shows the potential for {sup 3}He MRI to categorize or phenotype COPD ex-smokers, providing good evidence of feasibility for larger prospective studies.

  13. 比较简易精神状态量表与蒙特利尔认知评估量表在腔隙性脑梗死认知障碍患者中的应用价值%Comparison of the Application Value of Mini-mental State Examination and Montreal Cognitive Assessment in Lacunar Infarction Patients with Cognitive Impairment

    Institute of Scientific and Technical Information of China (English)

    肖桂荣; 孙新芳; 章燕幸; 赵宏军; 桂小红

    2012-01-01

    Objective To compare the application value of mini-mental state examination (MMSE) and Montreal cognitive assessment (MoCA) in detecting cognitive impairment in lacunar infarction (LI) patients. Methods The LI patients were first screened by MMSE,and those having a normal education-adjusted score were further assessed by MoCA (26 as the cut-off score). The patients with MoCA score less than 26 were selected into cognitive impaired Ii-CI group and the patients with more than 26 were classified as normal control LJ-NC group. Fifty healthy individuals were recruited in the healthy control group (NC group). The total score and the score of each cognitive field of MoCA among three groups was compared and analyzed. Results 53% (50/94) LI patients with normal MMSE had MoCA < 26. There was a statistical significant difference (P < 0.01) of the cognitive function between these cases and patients with MoCA = 26. The MoCA score of LI-CI group was less than li-NC group in visuospatial, executive, naming, delayed recall, abstraction and so on. The differences were statistical significant (P < 0.05). Conclusion The cognitive impairment of those patients with normal MMSE score but abnormal MoCA score were mainly in visuospatial, executive, naming, delayed recall, abstraction and so on. MoCA is more sensitive than MMSE in cognitive impairment screening in LI patients.%目的 比较简易精神状态(MMSE)量表与蒙特利尔认知评估(MoCA)量表(中文版)在腔隙性脑梗死患者认知障碍评估中的应用价值.方法 首先采用中文版MMSE量表对确诊为腔隙性脑梗死的患者进行筛选,然后对经过受教育程度矫正后MMSE得分正常的患者采用中文版MoCA量表进行评分.MoCA<26分者纳入腔隙性脑梗死认知功能障碍(LI-CI)组,MoCA≥26分者纳入腔隙性脑梗死认知功能正常( LI-NC)组,另选50例健康体检者作为对照(NC)组.比较3组患者MoCA总分及各个认知领域的得分情况.结果 MMSE

  14. Application Value of Montreal Cognitive Assessment in Lacunar Infarction Patients with Cognitive Impairment%蒙特利尔认知评估量表对腔隙性脑梗死患者认知功能障碍的评估价值研究

    Institute of Scientific and Technical Information of China (English)

    肖桂荣; 孙新芳; 章燕幸; 赵宏军; 桂小红

    2012-01-01

    目的 探讨蒙特利尔认知评估量表(Montreal Cognitive Assessment,MoCA)(中文版)在腔隙性脑梗死患者认知功能障碍评估中的应用价值.方法 首先采用中文版简易智能状态量表(Mini-Mental State Examination,MMSE)对确诊为腔隙性脑梗死患者进行筛选,然后对经过受教育程度矫正后MMSE得分正常的患者采用中文版MoCA进行评分,使用26分作为分界值.MoCA<26分者纳入腔隙性脑梗死认知功能障碍组(LI-CI组),MoCA≥26分者纳入腔隙性脑梗死认知功能正常组(LI-NC组).比较两组患者MoCA评分、MMSE评分及MoCA各个认知领域得分情况.结果 MMSE得分正常的患者有53%(50/94)MoCA评分<26分,这些患者的认知功能与MoCA评分≥26分的患者比较,差异有统计学意义﹙P<0.01﹚;LI-CI组在视空间功能与执行功能、命名、抽象、延迟回忆认知领域方面得分低于LI-NC组,差异均有统计学意义(P<0.05).结论 MoCA在筛查腔隙性脑梗死患者认知障碍方面可能比MMSE更为敏感,对于MMSE评分正常MoCA评测异常的患者认知损害主要表现在视空间与执行功能、命名、延迟记忆以及抽象等方面.%Objective To analyze the application value of Montreal Cognitive Assessment (MoCA) ( Chinese version ) in detecting cognitive impairment in patients with lacunar infarction (LI). Methods The patients confirmed with LI were first screened by Mini - Mental State Examination ( MMSE) , and patients having normal MMSE score were further assessed by MoCA after education adjustment (26 as the cut - off score). The patients with MoCA score less than 26 were selected as cognitive im-paired LI - CI group and the patients with more than 26 were selected as normal control LI - NC group. MoCA score, MMSE score and scores of each cognitive field of MoCA were compared between the two groups. Results 53% (50/94) Li patients with nor-mal MMSE score had MoCA socre < 26, and these patients' cognitive function

  15. Effects of Alpha-lipoic Acid on Congnitive Function in Lacunar Infarction Patients with Diabetes Mellitu%α-硫辛酸对腔隙性脑梗死伴糖尿病患者认知功能的影响

    Institute of Scientific and Technical Information of China (English)

    丛文东; 吴达荣; 曾佳; 高展

    2013-01-01

      目的:观察腔隙性脑梗死伴糖尿病患者的认知功能损害特点,并探讨α‐硫辛酸对其认知功能的影响。方法:伴有糖尿病的腔隙性脑梗死患者60例,随机分配在 A 组(30例,每天静脉使用α‐硫辛酸)和B组(30例,一般治疗)中,对照组(30例)选用健康体检人群。使用蒙特利尔认知评估量表(MOCA)分别对两组患者在发病后3天、3个月进行认知功能评估,并分别与正常对照组进行比较。结果:在脑梗死发病后3天,两组患者均出现视空间与执行功能、命名、延迟记忆、注意力和计算能力、语言、定向功能障碍,总分与对照组相比差异有显著性。在发病后3个月,使用硫辛酸组各项评分较一般治疗组高,总分及注意力、视空间与执行功能、定向力差异有统计学意义。结论:在伴有糖尿病的腔隙性脑梗死患者急性期认知损害广泛,α‐硫辛酸对认知功能具有保护作用。%  Objective:To explore the characters of cognitive dysfunction for lacunar infarction (L I) with diabetes mellitus and the protective effects of alpha‐lipoic acid .Methods :A total of 64 LI patients with dia‐betes mellitus randomly divided into 2 groups .Patients of group 1 (n=30) were treated with alpha ‐lipoic acid .Patients of group 2(n=30) were assigned conventional therapy .The cognitive function of patients were evaluated with Montreal Cognitive Assessment (MOCA) at 3days and 3months after attack .An additional control group consisted of age‐matched healthy (n=30) .Results:Compared with controls ,significant differ‐ence was found on the memory ,name ,language ,orientation ,attention ,executive function ,visuospatial and visuo‐constructive function at 3 days .Most cognitive domains were improved at 3 months of group 1 ,scores of general MoCA ,attention ,visuospatial and visuo‐constructive function and orientation were higher than those of

  16. 吡拉西坦联合丁苯酞软胶囊治疗腔隙性脑梗死合并血管性认知功能障碍观察%Clinical Observation of Piracetam Combined with Butylphthalide Soft Capsules in the Treatment of Patients with Lacunar Infarction Complicated with Vascular Cognitive Impairment

    Institute of Scientific and Technical Information of China (English)

    周幼峰

    2016-01-01

    Objective:To observe the clinical efficacy and safety of piracetam tablets combined with butylphthalide soft capsules in the treatment of patients with lacunar infarction(LI) complicated with vascular cognitive impairment(VCI). Methods:Totally 87 cases of patients with LI and VCI were selected and randomly divided into the control group(44 cases)and the treatment group(43 cases). The control group was only treated with piracetam tablets(1. 2 g,tid),while the treatment group was treated with piracetam tablets(1. 2 g,tid)and butylphthalide soft capsules(0. 2 g,qid),and the treatment course was 30 days. The changes of MMSE score,serum of SOD level and adverse drug reactions were observed and compared in the two groups. Results:Compared with those before the treatment,the mini-mental state examination(MMSE)score and serum level of SOD of the two groups were increased(P < 0. 01)after the treatment,and the increase in the treatment group was more notable than that in the control group(P < 0. 01and P < 0. 05). The effective rate of the treatment group was 86. 05% ,which was higher than that of the control group(75. 00% ,P < 0. 05). Conclusion:Piracetam combined with butylphthalide soft capsules can effectively improve the cognitive impairment of the patients with LI and VCI,and the effect may be related with increasing the level of SOD.%目的:观察吡啦西坦片联合丁苯酞软胶囊治疗腔隙性脑梗死(LI)合并血管性认知功能障碍(VCI)的临床疗效及安全性。方法:87例 LI 合并 VCI 患者随机分为对照组(44例)和观察组(43例)。对照组单用吡拉西坦片(1.2 g tid),观察组联用吡拉西坦片(1.2 g tid)和丁苯酞软胶囊(0.2 g qid),疗程均为30 d。观察两组患者 MMSE 积分、SOD 含量变化,比较两组疗效和药品不良反应。结果:两组患者治疗后 MMSE 积分、血清 SOD 水平均较前升高(P <0.01),且观察组优于对照组(P <0.05和 P

  17. The relationship between the level of plasma fibrinogen and carotid/lower limb atherosclerosis in patients with transient ischemic attack and single/multiple lacunar cerebral infarction%短暂性脑缺血发作、单/多发腔隙性脑梗死患者血纤维蛋白原水平与颈动脉及下肢动脉粥样硬化的相关性研究

    Institute of Scientific and Technical Information of China (English)

    季芳; 罗美芳; 李蕾

    2011-01-01

    目的 探讨短暂性脑缺血发作(transient ischemic attack,TIA)、单/多发腔隙性脑梗死患者颈动脉及下肢动脉粥样硬化情况,明确血纤维蛋白原水平对颈动脉及下肢动脉粥样硬化的影响.方法 对178例短暂性脑缺血发作、单/多发腔隙性脑梗死患者进行颈动脉及下肢动脉彩色多普勒超声检查,记录颈动脉及下肢动脉粥样硬化斑块的部位、大小、数目、回声、动脉分叉处内膜中层厚度(intima-media thickness,IMT)及血管内径,并测量血压及纤维蛋白原测定.结果 颈动脉粥样硬化斑块位于颈总动脉分叉处最多(占58.3%).IMT≥1.2 mm组血纤维蛋白原水平显著高于IMT<1.2 mm组(P<0.05).下肢动脉粥样硬化位于股动脉最多(占49.6%),IMT≥1.2 mm组血纤维蛋白原水平显著高于IMT<1.2 mm组(P<0.05).高水平纤维蛋白原组(≥3.0 g/L)易损斑块数量明显增多(P≤0.05).颈动脉IMT与患者收缩压、舒张压以及纤维蛋白原水平呈正相关(r=4.89、5.37、6.47,P均<0.05),下肢动脉IMT与血糖及纤维蛋白原水平呈正相关(r=4.83、5.38、6.68,P均<0.05).结论 血纤维蛋白原水平与短暂性脑缺血发作、单/多发腔隙性脑梗死患者颈动脉及下肢动脉粥样硬化程度呈正相关.%Objective To analyzes carotid/lower limb atheromatous plaque in patients with transient ischemic attack(TIA)、single/multiple lacunar cerebral infarction and explore the relationship between carotid/lower limb atherosclerosis and the levels of plasma fibrinogen.Methods In one hundred and seventy-eight cases of TIA or single/multiple lacunar cerebral infarction, the location, size, number, nature of carotid/lower limb atheromatous plaque, diameter of artety and intima-media thickness (IMT)of bifurcation of common carotid artery were assessed by Doppler ultrasonography, and other related indexes, such as blood pressure and the level of plasma fibirinogen were also evaluated.Results The carotid

  18. Dietary intake of saturated fatty acids and incident stroke and coronary heart disease in Japanese communities: the JPHC Study.

    Science.gov (United States)

    Yamagishi, Kazumasa; Iso, Hiroyasu; Kokubo, Yoshihiro; Saito, Isao; Yatsuya, Hiroshi; Ishihara, Junko; Inoue, Manami; Tsugane, Shoichiro

    2013-04-01

    Aims Although dietary saturated fatty acids (SFA) are considered atherogenic, associations between SFAs intake and stroke and coronary heart disease are still debated. We sought to test the hypothesis that SFA intake is associated inversely with risk of stroke and its subtypes and positively with coronary heart disease among Japanese, whose average SFA intake is lower than that of Westerners. Methods and results The Japan Public Health Center-based prospective Study involves two subcohorts: Cohort I, aged 45-64 in 1995 and followed-up through 2009, and Cohort II, aged 45-74 in 1998 and followed-up through 2007. A total of 38 084 men and 43 847 women were included in this report. Hazards ratios for incident total stroke, ischaemic stroke, intraparhenchymal haemorrhage, subarachnoid haemorrhage, myocardial infarction, and sudden cardiac death across quintiles of dietary SFAs were examined. We found inverse associations between SFA intake and total stroke [multivariable hazard ratio (95% confidence interval) for the highest vs. lowest quintiles = 0.77 (0.65-0.93), trend P = 0.002], intraparenchymal haemorrhage [0.61 (0.43-0.86), P for trend = 0.005], and ischaemic stroke [0.84 (0.67-1.06), trend P = 0.08], primarily for deep intraparenchymal haemorrhage [0.67 (0.45-0.99), P for trend = 0.04] and lacunar infarction [0.75 (0.53, 1.07), trend P = 0.02]. We also observed a positive association between SFAs intake and myocardial infarction [1.39 (0.93-2.08), trend P = 0.046] primarily among men. No associations were observed between SFAs intake and incidence of subarachnoid haemorrhage or sudden cardiac death. Conclusions In this Japanese population, SFAs intake was inversely associated with deep intraparenchymal haemorrhage and lacunar infarction and positively associated with myocardial infarction.

  19. The contribution of twins to the study of cognitive ageing and dementia: the Older Australian Twins Study.

    Science.gov (United States)

    Sachdev, Perminder S; Lee, Teresa; Wen, Wei; Ames, David; Batouli, Amir H; Bowden, Jocelyn; Brodaty, Henry; Chong, Elizabeth; Crawford, John; Kang, Kristan; Mather, Karen; Lammel, Andrea; Slavin, Melissa J; Thalamuthu, Anbupalam; Trollor, Julian; Wright, Margie J

    2013-12-01

    The Older Australian Twins Study (OATS) is a major longitudinal study of twins, aged ≥ 65 years, to investigate genetic and environmental factors and their interactions in healthy brain ageing and neurocognitive disorders. The study collects psychiatric, neuropsychological, cardiovascular, metabolic, biochemical, neuroimaging, genomic and proteomic data, with two-yearly assessments, and is currently in its third wave. The initial cohort comprises 623 individuals (161 monozygotic and 124 dizygotic twin pairs; 1 MZ triplets; 27 single twins and 23 non-twin siblings), of whom 426 have had wave 2 assessment. A number of salient findings have emerged thus far which assist in the understanding of genetic contributions to cognitive functions such as processing speed, executive ability and episodic memory, and which support the brain reserve hypothesis. The heritability of brain structures, both cortical and subcortical, brain spectroscopic metabolites and markers of small vessel disease, such as lacunar infarction and white matter hyperintensities, have been examined and can inform future genetic investigations. Work on amyloid imaging and functional magnetic resonance imaging is proceeding and epigenetic studies are progressing. This internationally important study has the potential to inform research into cognitive ageing in the future, and offers an excellent resource for collaborative work.

  20. Stroke in Kuwait: a three-year prospective study.

    Science.gov (United States)

    Abdul-Ghaffar, N U; el-Sonbaty, M R; el-Din Abdul-Baky, M S; Marafie, A A; al-Said, A M

    1997-01-01

    To study the pattern of stroke in Kuwait, prospective data were collected from all patients admitted with first-ever stroke to our hospital over 3 years: 1989, 1992 and 1993. The primary-care registry over the same period was examined to ascertain that all cases of stroke seen by the primary-care doctors were referred to a hospital. Death certificates issued for people who died outside the hospital were also examined. The study included: clinical evaluation, computed tomography, electrocardiography, blood laboratories, serum chemistry and other investigations as required. The overall annual crude incidence rate was 27.6/100,000 population. The age-adjusted annual crude incidence rate was 145.6/100,000 population. No seasonal variation in the stroke incidence was observed in our study. Carotid-territory large infarction represented 46.5% of all strokes followed by intracerebral haemorrhage in 19.9%, lacunar infarction in 17%, basilar infarction in 8.3% and subarachnoid haemorrhage in 1.7%. The overall case fatality rate was 10%. Mortality increased with age and when loss of consciousness was present. The study demonstrated that stroke incidence in Kuwait is very low due to the young average age of the Kuwaiti population.

  1. Pattern of hospitalized-stroke patients in ASEAN countries an ASNA stroke epidemiological study

    Directory of Open Access Journals (Sweden)

    Jusuf Misbach

    2001-03-01

    Full Text Available To better understanding the demographic characteristics, admission time, clinical pattern, risk factors, stroke type, length of stay, and discharge outcome of hospitalized acute stroke patients in ASEAN member countries, ASEAN   Neurological Association (ASNA formed a Standing Commiltee for Stroke in 1996 and this is the first ASNA Stroke Epidemiological Study using the same stroke protocol. This prospective hospital based study was conducted in seven ASEAN countries (Brunei, Indonesia, Malaysia, Philippines, Singapore, Thailand, and Vietnam by participating neurologists from October 1996 to March 1997. Of the 3723 consecutive hospitalized stroke patients (2030 males and 1660 females from 44 participating hospitals in this study ie Brunei (n=53, Indonesia (n=2065, Malaysia (n=300,Philippines (n=545,Singapore (n=232, Thailand (n=244 and Vietnam (n=284, the mean age was 59.0 ± 13,8 years 16% of patients were younger than 45 years and 37% of patients were older than 65 years. There were no significant differences in age at onset among stroke subjects except in Vietnam (younger and Singapore (older. The sex distribution showed a slight higher prevalence of women in Singapore and in the age group > 64 years. The mean adrnission time was 41.5 ± 87.0 hours, 19% of patients were admitted within 3 hours, 29% within 6 hours and 66% more than 6 hours (delayed admission especially in Malaysia and Singapore (80% and 77% respectively. Motor disability was the most prevalent clinical feature in all countries and carotid bruit was the rarest (1%. Hypertension was the most common risk factor (68% in all countries, followed by TIA (35%, smoking, diabetes mellitus, ischnemic heart disease and hypercholesterolemia. CT scan was performed on 76% of subjects. The diagnostic classification was non lacunar anterior circulation (32%, lacunar infarction (14%, hemorrhagic stroke (26%, SAH (4%. Mean length of stay was 11.4 ± 11.8 days. Most of the patients

  2. The 'silence' of silent brain infarctions may be related to chronic ischemic preconditioning and nonstrategic locations rather than to a small infarction size

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    Chao Feng

    2013-01-01

    Full Text Available OBJECTIVE: Silent brain infarctions are the silent cerebrovascular events that are distinguished from symptomatic lacunar infarctions by their 'silence'; the origin of these infarctions is still unclear. This study analyzed the characteristics of silent and symptomatic lacunar infarctions and sought to explore the mechanism of this 'silence'. METHODS: In total, 156 patients with only silent brain infarctions, 90 with only symptomatic lacunar infarctions, 160 with both silent and symptomatic lacunar infarctions, and 115 without any infarctions were recruited. Vascular risk factors, leukoaraiosis, and vascular assessment results were compared. The National Institutes of Health Stroke Scale scores were compared between patients with only symptomatic lacunar infarctions and patients with two types of infarctions. The locations of all of the infarctions were evaluated. The evolution of the two types of infarctions was retrospectively studied by comparing the infarcts on the magnetic resonance images of 63 patients obtained at different times. RESULTS: The main risk factors for silent brain infarctions were hypertension, age, and advanced leukoaraiosis; the main factors for symptomatic lacunar infarctions were hypertension, atrial fibrillation, and atherosclerosis of relevant arteries. The neurological deficits of patients with only symptomatic lacunar infarctions were more severe than those of patients with both types of infarctions. More silent brain infarctions were located in the corona radiata and basal ganglia; these locations were different from those of the symptomatic lacunar infarctions. The initial sizes of the symptomatic lacunar infarctions were larger than the silent brain infarctions, whereas the final sizes were almost equal between the two groups. CONCLUSIONS: Chronic ischemic preconditioning and nonstrategic locations may be the main reasons for the 'silence' of silent brain infarctions.

  3. Studying neutral hydrogen structures during the epoch of reionization using fractal dimensions

    CERN Document Server

    Bandyopadhyay, Bidisha; Seshadri, T R

    2016-01-01

    Fractal dimensions can be used to characterize the clustering and lacunarities in density distributions. We use generalized fractal dimensions to study the neutral hydrogen distribution (HI) during the epoch of reionization. Using a semi-numeric model of ionized bubbles to generate the HI field, we calculate the fractal dimensions for length scales $\\sim 10 h^{-1}$ cMpc. We find that the HI field displays significant multifractal behaviour and is not consistent with homogeneity at these scales when the mass averaged neutral fraction $\\bar{x}_{\\rm HI}^M \\gtrsim 0.5$. This multifractal nature is driven entirely by the shapes and distribution of the ionized regions. The sensitivity of the fractal dimension to the neutral fraction implies that it can be used for constraining reionization history. We find that the fractal dimension is relatively less sensitive to the value of the minimum mass of ionizing haloes when it is in the range $\\sim 10^9 - 10^{10} h^{-1} M_{\\odot}$. Interestingly, the fractal dimension is ...

  4. Characteristics of alveolar bone associated with physiological movement of molar in mice: a histological and histochemical study.

    Science.gov (United States)

    Matsuda, Kie; Haga-Tsujimura, Maiko; Yoshie, Sumio; Shimomura-Kuroki, Junko

    2014-01-01

    Mouse molars undergo distal movement, during which new bone is formed at the mesial side of the tooth root whereas the preexisting bone is resorbed at the distal side of the root. However, there is little detailed information available regarding which of the bones that surround the tooth root are involved in physiological tooth movement. In the present study, we therefore aimed to investigate the precise morphological differences of the alveolar bone between the bone formation side of the tooth root, using routine histological procedures including silver impregnation, as well as by immunohistochemical analysis of alkaline phosphatase and tartrate-resistant acid phosphatase activity, and immunohistochemical analysis of the expression of the osteocyte markers dentin matrix protein 1, sclerostin, and fibroblast growth factor 23. Histochemical analysis indicated that bone formation by osteoblasts and bone resorption by osteoclasts occurred at the bone formation side and the bone resorption side, respectively. Osteocyte marker immunoreactivity of osteocytes at the surface of the bone close to the periodontal ligament differed at the bone formation and bone resorption sides. We also showed different specific features of osteocytic lacunar canalicular systems at the bone formation and bone resorption sides by using silver staining. This study suggests that the alveolar bone is different in the osteocyte nature between the bone formation side and the bone resorption side due to physiological distal movement of the mouse molar.

  5. LACUNAR CONSTRUCTIONS “NOUN+ARTICLE” IN PUBLICIST-ORAL SPEECH OF ENGLISH AND GREEK

    Directory of Open Access Journals (Sweden)

    Fomenko L. N.

    2015-04-01

    Full Text Available This article describes some interesting facts of Modern English and Greek Grammar and pay our attention to extension of constructions “noun + article” without article in publicist-oral speech, where it should be. Our observations show some phenomena of evolution of system “noun + article”. This article is due to some cases of using articles, which we can’t often find in traditional native and foreign normal grammars. In English Grammar the ellipsis of article meets stylistic and syntax’s requirements. But there isn’t such limitation in Greek Grammar, that’s why on the one hand, we qualify the ellipsis of article as a realization of category determinacyindeterminacy, and on the other hand, we can see the generalization of the meaning of article. Illustrative materials are newspapers’ articles of classical British dialectical English and Dimotiki (oral New Greek.There are not only main rules of articles in periodical and oral speech, but also the meaning of nouns, which we can understand from surrounding context and geographical position, also as a style of periodical publications

  6. Application of Diffusion Tensor Imaging Parameters to Detect Change in Longitudinal Studies in Cerebral Small Vessel Disease.

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    Eva Anna Zeestraten

    Full Text Available Cerebral small vessel disease (SVD is the major cause of vascular cognitive impairment, resulting in significant disability and reduced quality of life. Cognitive tests have been shown to be insensitive to change in longitudinal studies and, therefore, sensitive surrogate markers are needed to monitor disease progression and assess treatment effects in clinical trials. Diffusion tensor imaging (DTI is thought to offer great potential in this regard. Sensitivity of the various parameters that can be derived from DTI is however unknown. We aimed to evaluate the differential sensitivity of DTI markers to detect SVD progression, and to estimate sample sizes required to assess therapeutic interventions aimed at halting decline based on DTI data. We investigated 99 patients with symptomatic SVD, defined as clinical lacunar syndrome with MRI confirmation of a corresponding infarct as well as confluent white matter hyperintensities over a 3 year follow-up period. We evaluated change in DTI histogram parameters using linear mixed effect models and calculated sample size estimates. Over a three-year follow-up period we observed a decline in fractional anisotropy and increase in diffusivity in white matter tissue and most parameters changed significantly. Mean diffusivity peak height was the most sensitive marker for SVD progression as it had the smallest sample size estimate. This suggests disease progression can be monitored sensitively using DTI histogram analysis and confirms DTI's potential as surrogate marker for SVD.

  7. Significance of Haemodynamic and Haemostatic Factors in the Course of Different Manifestations of Cerebral Small Vessel Disease: The SHEF-CSVD Study—Study Rationale and Protocol

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    Jacek Staszewski

    2013-01-01

    Full Text Available Rationale. This paper describes the rationale and design of the SHEF-CSVD Study, which aims to determine the long-term clinical and radiological course of cerebral small vessel disease (CSVD and to evaluate haemostatic and haemodynamic prognostic factors of the condition. Design. This single-centre, prospective, non-interventional cohort study will follow 150 consecutive patients with different clinical manifestations of CSVD (lacunar ischaemic stroke, vascular dementia, vascular parkinsonism or spontaneous deep, intracerebral haemorrhage and 50 age- and sex-matched controls over a period of 24 months. The clinical and radiological course will be evaluated basing on a detailed neurological, neuropsychological and MRI examinations. Haemodynamic (cerebral vasoreactivity, 24 h blood pressure control and haemostatic factors (markers of endothelial and platelet dysfunction, brachial artery flow-mediated dilatation test will be determined. Discussion. The scheduled study will specifically address the issue of haemodynamic and haemostatic prognostic factors and their course over time in various clinical manifestations of CSVD. The findings may aid the development of prophylactic strategies and individualised treatment plans, which are critical during the early stages of the disease.

  8. Causes of cerebral small vessel disease : a prospective population-based MRI study

    NARCIS (Netherlands)

    E.J. van Dijk (Ewoud)

    2004-01-01

    markdownabstract__Abstract__ In the 1970s, the introduction of computed tomography (CT) and magnetic resonance imaging (MRI) in medicine, made it possible to image the living brain. These images showed that cerebral white matter lesions and asymptomatic lacunar brain infarcts are extremely common i

  9. Modelling Applicability of Fractal Analysis to Efficiency of Soil Exploration by Roots

    OpenAIRE

    Walk, Thomas C.; van Erp, Erik; Lynch, Jonathan P.

    2004-01-01

    • Background and Aims Fractal analysis allows calculation of fractal dimension, fractal abundance and lacunarity. Fractal analysis of plant roots has revealed correlations of fractal dimension with age, topology or genotypic variation, while fractal abundance has been associated with root length. Lacunarity is associated with heterogeneity of distribution, and has yet to be utilized in analysis of roots. In this study, fractal analysis was applied to the study of root architecture and acquisi...

  10. Diabetes and hypertension markedly increased the risk of ischemic stroke associated with high serum resistin concentration in a general Japanese population: the Hisayama Study

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    Kawamura Ryoichi

    2009-11-01

    Full Text Available Abstract Background Resistin, secreted from adipocytes, causes insulin resistance in mice. The relationship between resistin and coronary artery disease is highly controversial, and the information regarding resistin and ischemic stroke is limited. In the present study, the association between serum resistin concentration and cardiovascular disease (CVD was investigated in a general Japanese population. Methods A total of 3,201 community-dwelling individuals aged 40 years or older (1,382 men and 1,819 women were divided into quintiles of serum resistin, and the association between resistin and CVD was examined cross-sectionally. The combined effect of either diabetes or hypertension and high serum resistin was also assessed. Serum resistin was measured using ELISA. Results Compared to those without CVD, age- and sex-adjusted mean serum resistin concentrations were greater in subjects with CVD (p = 0.002 or ischemic stroke (p Conclusion Elevated serum resistin concentration appears to be an independent risk factor for ischemic stroke, especially lacunar and atherothrombotic infarction in the general Japanese population. The combination of high resistin and the presence of either diabetes or hypertension increased the risk of ischemic stroke.

  11. A quantitative approach to scar analysis.

    Science.gov (United States)

    Khorasani, Hooman; Zheng, Zhong; Nguyen, Calvin; Zara, Janette; Zhang, Xinli; Wang, Joyce; Ting, Kang; Soo, Chia

    2011-02-01

    Analysis of collagen architecture is essential to wound healing research. However, to date no consistent methodologies exist for quantitatively assessing dermal collagen architecture in scars. In this study, we developed a standardized approach for quantitative analysis of scar collagen morphology by confocal microscopy using fractal dimension and lacunarity analysis. Full-thickness wounds were created on adult mice, closed by primary intention, and harvested at 14 days after wounding for morphometrics and standard Fourier transform-based scar analysis as well as fractal dimension and lacunarity analysis. In addition, transmission electron microscopy was used to evaluate collagen ultrastructure. We demonstrated that fractal dimension and lacunarity analysis were superior to Fourier transform analysis in discriminating scar versus unwounded tissue in a wild-type mouse model. To fully test the robustness of this scar analysis approach, a fibromodulin-null mouse model that heals with increased scar was also used. Fractal dimension and lacunarity analysis effectively discriminated unwounded fibromodulin-null versus wild-type skin as well as healing fibromodulin-null versus wild-type wounds, whereas Fourier transform analysis failed to do so. Furthermore, fractal dimension and lacunarity data also correlated well with transmission electron microscopy collagen ultrastructure analysis, adding to their validity. These results demonstrate that fractal dimension and lacunarity are more sensitive than Fourier transform analysis for quantification of scar morphology.

  12. A CLINICAL STUDY OF STROKE IN YOUNG

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    Kumbha Thulasi Ram

    2015-02-01

    Full Text Available NTRIDUCTION : Stroke is one of the important causes of morbidity and mortality all over the world. Incidence of stroke steadily increases with age. Experts are concerned of the emerging stroke epidemic in India. Stroke affecting the young has potentially devastating consequence son the individual and his family. Certain risk factors are unique to the young. I t needs more studies for identification and modification of risk factors. The study aims to evaluate clinical features, risk factors, etiology and mortality of stroke in young patients. METHODS : 74 young patients satisfying the inclusion criteria were included in this study. A detailed history was taken from young stroke patients, systemic examination and required investigations were done. Data was collected in standardized proforma and analysed. RESULTS: Stroke in young accounts for 7.95% of stroke cases of all age groups. The mean age of the patients was 34.66 ± 7.48 years. Among 74 patients, 47(63.51% were male and 27(36.49% were female. Seizures, decreased consciousness, speech involvement and motor deficit were observed in 33.78%, 44.59%, 22.97% and 100% of cases respectively. 82.43% patients had ischemic and 17.57% patients had hemorrhagic stroke. Among ischemic stroke, large artery atherosclerosis was 16.21%, tuberculous meningoencephalitis with vasculitis was 16.21%, lacunar stroke was 10.81%, CVT was 10.81% and cardio embolic stroke was 6.76%. Smoking (59.45%, alcoholism (58.10%, hypertension (43.24%, coronary artery disease (8.10%, diabetes mellitus (10.81%, elevated total cholesterol (25.67%, elevated low density lipo proteins (22.97%, elevated triglycerides (27.02% and low HDL (22.97% were important risk factors. Carotid doppler was abnormal in 9.45% of patients. 6.76% patients had mitral stenosis in echocardiogram. Low protein C and protein S were found in 1.35% of patients. Eight (10.81% patients died during the hospital stay. INTERPRETATION AND CONCLUSIONS: The major risk

  13. Novel computer vision algorithm for the reliable analysis of organelle morphology in whole cell 3D images--A pilot study for the quantitative evaluation of mitochondrial fragmentation in amyotrophic lateral sclerosis.

    Science.gov (United States)

    Lautenschläger, Janin; Lautenschläger, Christian; Tadic, Vedrana; Süße, Herbert; Ortmann, Wolfgang; Denzler, Joachim; Stallmach, Andreas; Witte, Otto W; Grosskreutz, Julian

    2015-11-01

    The function of intact organelles, whether mitochondria, Golgi apparatus or endoplasmic reticulum (ER), relies on their proper morphological organization. It is recognized that disturbances of organelle morphology are early events in disease manifestation, but reliable and quantitative detection of organelle morphology is difficult and time-consuming. Here we present a novel computer vision algorithm for the assessment of organelle morphology in whole cell 3D images. The algorithm allows the numerical and quantitative description of organelle structures, including total number and length of segments, cell and nucleus area/volume as well as novel texture parameters like lacunarity and fractal dimension. Applying the algorithm we performed a pilot study in cultured motor neurons from transgenic G93A hSOD1 mice, a model of human familial amyotrophic lateral sclerosis. In the presence of the mutated SOD1 and upon excitotoxic treatment with kainate we demonstrate a clear fragmentation of the mitochondrial network, with an increase in the number of mitochondrial segments and a reduction in the length of mitochondria. Histogram analyses show a reduced number of tubular mitochondria and an increased number of small mitochondrial segments. The computer vision algorithm for the evaluation of organelle morphology allows an objective assessment of disease-related organelle phenotypes with greatly reduced examiner bias and will aid the evaluation of novel therapeutic strategies on a cellular level.

  14. Pattern and Rate of Cognitive Decline in Cerebral Small Vessel Disease: A Prospective Study.

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    Andrew J Lawrence

    Full Text Available Cognitive impairment, predominantly affecting processing speed and executive function, is an important consequence of cerebral small vessel disease (SVD. To date, few longitudinal studies of cognition in SVD have been conducted. We determined the pattern and rate of cognitive decline in SVD and used the results to determine sample size calculations for clinical trials of interventions reducing cognitive decline.121 patients with MRI confirmed lacunar stroke and leukoaraiosis were enrolled into the prospective St George's Cognition And Neuroimaging in Stroke (SCANS study. Patients attended one baseline and three annual cognitive assessments providing 36 month follow-up data. Neuropsychological assessment comprised a battery of tests assessing working memory, long-term (episodic memory, processing speed and executive function. We calculated annualized change in cognition for the 98 patients who completed at least two time-points.Task performance was heterogeneous, but significant cognitive decline was found for the executive function index (p<0.007. Working memory and processing speed decreased numerically, but not significantly. The executive function composite score would require the smallest samples sizes for a treatment trial with an aim of halting decline, but this would still require over 2,000 patients per arm to detect a 30% difference with power of 0.8 over a three year follow-up.The pattern of cognitive decline seen in SVD over three years is consistent with the pattern of impairments at baseline. Rates of decline were slow and sample sizes would need to be large for clinical trials aimed at halting decline beyond initial diagnosis using cognitive scores as an outcome measure. This emphasizes the importance of more sensitive surrogate markers in this disease.

  15. Achieved Blood Pressures in the Secondary Prevention of Small Subcortical Strokes (SPS3) Study: Challenges and Lessons Learned

    Science.gov (United States)

    Pergola, Pablo E.; Szychowski, Jeff M.; Talbert, Robert; del Brutto, Oscar; Castellanos, Mar; Graves, John W.; Matamala, Gonzalo; Pretell, Edwin Javier; Yee, Jerry; Rebello, Rosario; Zhang, Yu; Benavente, Oscar R.

    2014-01-01

    BACKGROUND Lowering blood pressure (BP) after stroke remains a challenge, even in the context of clinical trials. The Secondary Prevention of Small Subcortical Strokes (SPS3) BP protocol, BP management during the study, and achieved BPs are described here. METHODS Patients with recent symptomatic lacunar stroke were randomized to 1 of 2 levels of systolic BP (SBP) targets: lower: <130mm Hg, or higher: 130–149mm Hg. SBP management over the course of the trial was examined by race/ethnicity and other baseline conditions. RESULTS Mean SBP decreased for both groups from baseline to the last follow-up, from 142.4 to 126.7mm Hg for the lower SBP target group and from 143.6 to 137.4mm Hg for the higher SBP target group. At baseline, participants in both groups used an average of 1.7±1.2 antihypertensive medications, which increased to a mean of 2.4±1.4 (lower group) and 1.8±1.4 (higher group) by the end-study visit. It took an average of 6 months for patients to reach their SBP target, sustained to the last follow-up. Black participants had the highest proportion of SBP ≥150mm Hg at both study entry (40%) and end-study visit (17%), as compared with whites (9%) and Hispanics (11%). CONCLUSIONS These results show that it is possible to safely lower BP even to a SBP goal <130mm Hg in a variety of patients and settings, including private and academic centers in multiple countries. This provides further support for protocol-driven care in lowering BP and consequently reducing the burden of stroke. PMID:24610884

  16. Study on the Prevalence and Corelation of Carotid Atherosclerosis in Stroke Patients

    Institute of Scientific and Technical Information of China (English)

    Wei Hua; Wang Yongjun; Yah Zhenying

    2000-01-01

    Objective To assess the prevalence and severity of carotid atherosclerosis in stroke patients and the risk factors of carotid atherosclerosis. Methods Two hundred fifty-one ischemic stroke patients,46 ccrcbral hemorrhagc patients and 96 control subjects were entercd into this study. Sonographic assessment of the extracranial carotid arteries was performed in all patients. Diametcr. IMT, plaques and percentage ratio of lumen stenosis were observcd. Results (1)The prevalence of carotid plaqucs was prominent in stroke patients than the control subjects(63.0%vs 36.5%). (2)The prevalencc of lumen stenosis>50% in ischemic stroke patients was higher than the cerebral hemorrhage patients and control subjects (15.6% vs 4.3%. 2.1%).(3) The prevalence of severe carotid artery stcnosis(>75%) was promincnt in aged 61~70 years old patients.(4)Our data revealed 30% of the cortical infarction subgroup, 17.5%of the subcortical infarction subgroup, 17% of the lacunar infarction subgroup,8% of the vcrtibral-basilar artery infarction subgroup.2.8% of thc CT normal subgroup possessed carotid stcnosis >50%. (5)Age, diabetes mellitus and ApoAl(inversely) were independent predictors of the extracranial carotid atherosclcrosis. Discusssion (Ⅰ)There is close relation between extracraniai carotid atherosclerosis and ischemic cerebrovascular disease.(2)The extent of serious carotid artery stcnosis in aged patients was lower.(3)Thc severity of extracranial carotid artery atherosclerosis was prominent in patients with conical infarction. Conclusion There is a high prevalence of extracranial carotid atherosclerosis in Chinese stroke patients.

  17. Posture-Dependent Human 3He Lung Imaging in an Open Access MRI System: Initial Results

    CERN Document Server

    Tsai, L L; Li, C -H; Rosen, M S; Patz, S; Walsworth, R L

    2007-01-01

    The human lung and its functions are extremely sensitive to orientation and posture, and debate continues as to the role of gravity and the surrounding anatomy in determining lung function and heterogeneity of perfusion and ventilation. However, study of these effects is difficult. The conventional high-field magnets used for most hyperpolarized 3He MRI of the human lung, and most other common radiological imaging modalities including PET and CT, restrict subjects to lying horizontally, minimizing most gravitational effects. In this paper, we briefly review the motivation for posture-dependent studies of human lung function, and present initial imaging results of human lungs in the supine and vertical body orientations using inhaled hyperpolarized 3He gas and an open-access MRI instrument. The open geometry of this MRI system features a "walk-in" capability that permits subjects to be imaged in vertical and horizontal positions, and potentially allows for complete rotation of the orientation of the imaging su...

  18. Study

    Directory of Open Access Journals (Sweden)

    Susan Grandy

    2012-01-01

    Full Text Available Purpose. This study examined the association between self-reported weight change and quality of life, and exercise and weight management behaviors among individuals with type 2 diabetes mellitus (T2DM. Methods. In the US SHIELD study, respondents reported whether they had lost or gained weight compared with 1 year earlier and completed the SHIELD-WQ-9 quality of life questionnaire as well as provided information on their exercise and weight management behaviors in the past 12 months. Results. Sixteen percent of the respondents reported gaining weight (n=460, and 30% reported losing weight (n=895. More respondents who reported losing weight exercised regularly, limited calorie and fat intake, and increased fiber, fruit, and vegetable intake compared with respondents who reported gaining weight (P<0.01. For all nine aspects of daily life, a significantly greater proportion of respondents who reported losing weight reported improved well-being (12%–44% compared with respondents who reported gaining weight (P<0.0001. Conclusions. Self-reported weight loss was associated with improved well-being, better exercise, and weight management behaviors among individuals with T2DM.

  19. Cerebral Small Vessel Disease and Risk of Death, Ischemic Stroke, and Cardiac Complications in Patients With Atherosclerotic Disease The Second Manifestations of ARTerial disease-Magnetic Resonance (SMART-MR) Study

    NARCIS (Netherlands)

    M.M.A. Conijn; R.P. Kloppenborg; A. Algra; W.P.T.M. Mali; L.J. Kappelle; K.L. Vincken; Y. van der Graaf; M.I. Geerlings

    2011-01-01

    Background and Purpose-Cerebral small vessel disease may be related to vascular and nonvascular pathology. We assessed whether lacunar infarcts and white matter lesions on MRI increased the risk of vascular and nonvascular death and future vascular events in patients with atherosclerotic disease. Me

  20. Assessment of lung disease in children with cystic fibrosis using hyperpolarized 3-Helium MRI: comparison with Shwachman score, Chrispin-Norman score and spirometry

    Energy Technology Data Exchange (ETDEWEB)

    Beek, Edwin J.R. van [University of Sheffield, Unit of Academic Radiology, Sheffield (United Kingdom); University of Iowa, Department of Radiology, Carver College of Medicine, Iowa City (United States); University of Iowa, Department of Radiology, Iowa City, IA (United States); Hill, Catherine; Woodhouse, Neil; Fichele, Stanislao; Fleming, Sally; Wild, Jim M. [University of Sheffield, Unit of Academic Radiology, Sheffield (United Kingdom); Howe, Bridget; Bott, Sandra; Taylor, Christopher J. [University of Sheffield, Academic Unit of Child Health, Sheffield (United Kingdom)

    2007-04-15

    This study assesses the feasibility of hyperpolarized 3-Helium MRI in children with cystic fibrosis (CF) and correlates the findings with standard clinical parameters based on chest radiograph (CXR) and pulmonary function tests (PFT). An uncontrolled, observational study in eighteen children with cystic fibrosis aged 5 - 17 years (median 12.1 years), with different severity of disease was carried out. All subjects underwent routine clinical assessment including PFT and standard auxology; CXR was obtained and Shwachman and Chrispin-Norman scores calculated. Hyperpolarized 3-He magnetic resonance imaging (MRI) was carried out using a spin-exchange polarizer and a whole body 1.5 T scanner. Ventilation distribution images were obtained during a 21-second breath-hold and scored according to previously defined criteria. Spearman's non-parametric correlations test was performed to assess for statistical significance at the p<0.05 level. The children tolerated the procedure well. No desaturation events were observed during 3-He MRI. A significant, albeit moderate, correlation was found between MRI score and FEV1% predicted (r=-0.41; p=0.047) and FVC% predicted (r=-0.42; p=0.04), while there were trends of correlations between Shwachman score and MRI score (r=-0.38; p=0.06) and Shwachman score and FEV1% predicted (r=0.39; p=0.055). The feasibility of hyperpolarized 3-He MRI in children with CF was demonstrated. MRI appears to be able to demonstrate functional lung changes, although correlations with routine clinical tests are only moderate to poor. This non-ionising radiation technique could be useful for monitoring lung disease and assessing therapy in this patient population. (orig.)

  1. Quantitative {sup 1}H and hyperpolarized {sup 3}He magnetic resonance imaging: Comparison in chronic obstructive pulmonary disease and healthy never-smokers

    Energy Technology Data Exchange (ETDEWEB)

    Owrangi, Amir M., E-mail: aowrangi@robats.ca [Imaging Research Laboratories, Robarts Research Institute, 100 Perth Drive, London, Canada N6A 5K8 (Canada); Graduate Program in Biomedical Engineering, The University of Western Ontario, London (Canada); Wang, Jian X., E-mail: jxwang@robats.ca [Imaging Research Laboratories, Robarts Research Institute, 100 Perth Drive, London, Canada N6A 5K8 (Canada); Applied Science Laboratories, General Electric Healthcare (Canada); Wheatley, Andrew, E-mail: awheat@imaging.robarts.ca [Imaging Research Laboratories, Robarts Research Institute, 100 Perth Drive, London, Canada N6A 5K8 (Canada); McCormack, David G., E-mail: David.Mccormack@lhsc.on.ca [Imaging Research Laboratories, Robarts Research Institute, 100 Perth Drive, London, Canada N6A 5K8 (Canada); Division of Respirology, Department of Medicine, The University of Western Ontario, London (Canada); Parraga, Grace, E-mail: gparraga@robats.ca [Imaging Research Laboratories, Robarts Research Institute, 100 Perth Drive, London, Canada N6A 5K8 (Canada); Graduate Program in Biomedical Engineering, The University of Western Ontario, London (Canada); Department of Medical Imaging, The University of Western Ontario, London (Canada); Department of Medical Biophysics, The University of Western Ontario, London (Canada)

    2014-01-15

    Objective: The aim of this study was to quantitatively evaluate the relationship between short echo time pulmonary {sup 1}H magnetic resonance imaging (MRI) signal intensity (SI) and {sup 3}He MRI apparent diffusion coefficients (ADC), high-resolution computed tomography (CT) measurements of emphysema, and pulmonary function measurements. Materials and methods: Nine healthy never-smokers and 11 COPD subjects underwent same-day plethysmography, spirometry, short echo time ((TE) = 1.2 ms) {sup 1}H and diffusion-weighted hyperpolarized {sup 3}He MRI (b = 1.6 s/cm{sup 2}) at 3.0 T. In addition, for COPD subjects only, CT densitometry was also performed. Results: Mean {sup 1}H SI was significantly greater for never-smokers (12.1 ± 1.1 arbitrary units (AU)) compared to COPD subjects (10.9 ± 1.3 AU, p = 0.04). The {sup 1}H SI AP-gradient was also significantly greater for never-smokers (0.40 AU/cm, R{sup 2} = 0.94) compared to COPD subjects (0.29 AU/cm, R{sup 2} = 0.968, p = 0.05). There was a significant correlation between {sup 1}H SI and {sup 3}He ADC (r = −0.58, p = 0.008) and significant correlations between {sup 1}H MR SI and CT measurements of emphysema (RA{sub 950}, r = −0.69, p = 0.02 and HU{sub 15}, r = 0.66, p = 0.03). Conclusions: The significant and moderately strong relationship between {sup 1}H SI and {sup 3}He ADC, as well as between {sup 1}H SI and CT measurements of emphysema suggests that these imaging methods and measurements may be quantifying similar tissue changes in COPD and that pulmonary {sup 1}H SI may be used to monitor emphysema as a complement to CT and noble gas MRI.

  2. Studies on intracranial collateral circulation with multi-slice CT angiography in patients with symptomatic cerebral artery stenosis

    Directory of Open Access Journals (Sweden)

    Shu-qing ZHOU

    2011-06-01

    Full Text Available Objective To explore the features of intracranial collateral circulation in patients with symptomatic cerebral artery stenosis.Method Ninety-four patients with ischemic cerebrovascular disease admitted from Apr.2004 to Jun.2009 were involved in present study.All the patients were examined with cerebral multi-slice CT angiography,and the features of cerebral artery stenosis and intracranial collateral circulation were evaluated using maximum intensity projection(MIP and volume rendering(VR images of CT angiography.Result Of the 94 patients involved,48 were diagnosed as cerebral artery stenosis,including 29 cases of cerebral infarction,18 of transient ischemic attack(TIA and 1 of moyamoya disease(MMD.Among the 14 cases of severe cerebral artery stenosis or occlusion,cerebral infarction was found in 6 cases with lesser intracranial collateral vessels(including massive cerebral infarction in 4 cases and watershed infarction in 2 cases,and focal infarction of central semi-ovale in 1 case and TIA in 7 cases were found with abundant intracranial collateral vessels.Multiple lacunar infarction was found in 22 cases of mild or moderate cerebral artery stenosis,but there was no significant correlation between the stenosed arteries and infarction sites.Abundant intracranial collateral vessels were found in one patient with Moyamoya disease but no infarction was observed.Conclusions Intracranial collateral circulation plays an important role of compensation in patients with severe cerebral artery stenosis or occlusion.Cerebral angiography with multi-slice CT is of great significance in evaluation of cerebral artery stenosis and intracranial collateral circulation.

  3. Five-year prognosis after mild to moderate ischemic stroke by stroke subtype: a multi-clinic registry study.

    Directory of Open Access Journals (Sweden)

    Yumei Lv

    Full Text Available BACKGROUND AND PURPOSE: Mild to moderate ischemic stroke is a common presentation in the outpatient setting. Among the various subtypes of stroke, lacunar infarction (LI is generally very common. Currently, little is known about the long-term prognosis and factors associated with the prognosis between LI and non-LI. This study aims to compare the risk of death and acute cardiovascular events between patients with LI and non-LI, and identify potential risk factors associated with these outcomes. METHODS: A total of 710 first-ever ischemic stroke patients (LI: 474, non-LI: 263 from 18 clinics were recruited consecutively from 2003 to 2004. They were prospectively followed-up until the end of 2008. Hazard ratios and 95% confidence intervals were calculated using multivariable Cox proportional hazards regression. RESULTS: After a 5-year follow up, 54 deaths and 96 acute cardiovascular events occurred. Recurrent stroke was the most common cause of death (19 cases, 35.18% and new acute cardiovascular events (75 cases, 78.13%. There were no significant differences between patients with LI and non-LI in their risks of death, new cardiovascular events, and recurrent stroke after adjusting for age, sex, hypertension, diabetes, cardiac diseases, body mass index, dyslipidemia, smoking, alcohol consumption, ADL dependence, and depressive symptoms. Among the modifiable risk factors, diabetes, hypertension, ADL dependency, and symptoms of depression were independent predictors of poor outcomes in patients with LI. In non-LI patients, however, no modifiable risk factors were detected for poor outcomes. CONCLUSION: Long-term outcomes did not differ significantly between LI and non-LI patients. Detecting and managing vascular risk factors and depression as well as functional rehabilitation may improve the prognoses of LI patients.

  4. Cortical changes in cerebral small vessel diseases: a 3D MRI study of cortical morphology in CADASIL

    Energy Technology Data Exchange (ETDEWEB)

    Jouvent, E.; Bousser, M.G.; Chabriat, H. [CHU Lariboisiere, AP HP, INSERM, UMR 740, Dept Neurol, Lariboisiere (France); Jouvent, E.; Bousser, M.G.; Chabriat, H. [Univ Paris 07, F-75221 Paris 05 (France); Porcher, R. [Hop St Louis, AP-HP, Dept Biostat, St Louis (France); Viswanathan, A. [Massachusetts Gen Hosp, Dept Neurol, Boston, MA 02114 (United States); Viswanathan, A. [Massachusetts Gen Hosp, Clin Trials Unit, Boston, MA 02114 (United States); Viswanathan, A. [Harvard Univ, Sch Med, Boston, MA (United States); O' Sullivan, M.; Dichgans, M. [Univ Munich, Klinikum Grosshadern, Dept Neurol, D-81377 Munich (Germany); Guichard, J.P. [CHU Lariboisiere, AP-HP, Dept Neuroradiol, Lariboisiere (France)

    2008-07-01

    Brain atrophy represents a key marker of disease progression in cerebrovascular disorders. The 3D changes of cortex morphology occurring during the course of small vessel diseases of the brain (SVDB) remain poorly understood. The objective of this study was to assess the changes affecting depth and surface area of cortical sulci and their clinical and radiological correlates in a cohort of patients with cerebral autosomal dominant arteriolopathy with subcortical infarcts and leukoencephalopathy (CADASIL), a genetic SVDB. Data were obtained from a series of 69 CADASIL patients. Validated methods were used to determine depth and surface area of four cortical sulci. The ratio of brain to intracranial cavity volumes (brain parenchymal fraction-BPF), volume of lacunar lesions (LL) and of white matter hyper-intensities, number of cerebral micro-haemorrhages, and mean apparent diffusion coefficient were also measured. Association between depth and surface area of the cortical sulci and BPF, clinical status and subcortical MRI lesions were tested. Depth and surface area of cortical sulci obtained in 54 patients were strongly correlated with both cognitive score and disability scales. Depth was related to the extent of subcortical lesions, surface area was related only to age. In additional analyses, the depth of the cingular sulcus was independently associated with the volume of LL (P 0.001), and that of the superior frontal sulcus with the mean apparent diffusion coefficient (P 0.003). In CADASIL, important morphological changes of cortical sulci occur in association with clinical worsening,extension of subcortical tissue damage and progression of global cerebral atrophy. These results suggest that the examination of cortical morphology may be of high clinical relevance in SVDB. (authors)

  5. Impact of cerebral white matter changes on functionality in older adults: An overview of the LADIS Study results and future directions.

    Science.gov (United States)

    Pantoni, Leonardo; Fierini, Fabio; Poggesi, Anna

    2015-12-01

    The evidence on the clinical significance of cerebral white matter changes (WMC) has mounted over the past few decades. WMC are recognized as one of the neuroimaging features of cerebral small vessel disease, and are associated with various disturbances and a poor prognosis. The Leukoaraiosis and Disability (LADIS) Study has contributed substantially to this body of knowledge. LADIS is a European multicenter collaboration aimed at assessing the role of WMC as an independent predictor of the transition to disability in initially non-disabled patients aged 65-84 years. Besides the demonstration that severe WMC cause a more than double risk of transition from an autonomous to a dependent status after 3 years of follow-up, the LADIS Study has also provided evidence on the role of WMC in relation to the decline of cognitive and motor performances, depressive symptoms associated with aging and cerebrovascular diseases, the presence of urinary disturbances, and various neurological abnormalities. The possible role of other lesions (lacunar infarcts, cerebral atrophy, corpus callosum morphology) and microstructural abnormalities (diffusion-weighted imaging changes in normal appearing brain tissue and in WMC) has also been investigated. In the present article, we review the main results of the LADIS Study and offer some considerations for future developments in the field, paying attention to the potential use of WMC progression as a surrogate marker in intervention trials in cerebral small vessel diseases. We also discuss some therapeutic perspectives regarding the beneficial impact of physical activity on the risk of vascular cognitive impairment in patients with WMC.

  6. 3D Porous Architecture of Stacks of β-TCP Granules Compared with That of Trabecular Bone: A microCT, Vector Analysis, and Compression Study.

    Science.gov (United States)

    Chappard, Daniel; Terranova, Lisa; Mallet, Romain; Mercier, Philippe

    2015-01-01

    The 3D arrangement of porous granular biomaterials usable to fill bone defects has received little study. Granular biomaterials occupy 3D space when packed together in a manner that creates a porosity suitable for the invasion of vascular and bone cells. Granules of beta-tricalcium phosphate (β-TCP) were prepared with either 12.5 or 25 g of β-TCP powder in the same volume of slurry. When the granules were placed in a test tube, this produced 3D stacks with a high (HP) or low porosity (LP), respectively. Stacks of granules mimic the filling of a bone defect by a surgeon. The aim of this study was to compare the porosity of stacks of β-TCP granules with that of cores of trabecular bone. Biomechanical compression tests were done on the granules stacks. Bone cylinders were prepared from calf tibia plateau, constituted high-density (HD) blocks. Low-density (LD) blocks were harvested from aged cadaver tibias. Microcomputed tomography was used on the β-TCP granule stacks and the trabecular bone cores to determine porosity and specific surface. A vector-projection algorithm was used to image porosity employing a frontal plane image, which was constructed line by line from all images of a microCT stack. Stacks of HP granules had porosity (75.3 ± 0.4%) and fractal lacunarity (0.043 ± 0.007) intermediate between that of HD (respectively 69.1 ± 6.4%, p TCP granules than bone trabecule. Stacks of HP granules represent a scaffold that resembles trabecular bone in its porous microarchitecture.

  7. Cerebral Microbleeds and White Matter Hyperintensities in Cognitively Healthy Elderly: A Cross-Sectional Cohort Study Evaluating the Effect of Arterial Stiffness

    Directory of Open Access Journals (Sweden)

    Anna-Märta Gustavsson

    2015-05-01

    Full Text Available Background: Arterial stiffness reflects the ageing processes in the vascular system, and studies have shown an association between reduced cognitive function and cerebral small vessel disease. Small vessel disease can be visualized as white matter hyperintensities (WMH and lacunar infarcts but also as cerebral microbleeds on brain magnetic resonance imaging (MRI. We aimed to investigate if arterial stiffness influences the presence of microbleeds, WMH and cognitive function in a population of cognitively healthy elderly. Methods: The study population is part of the Swedish BioFinder study and consisted of 208 individuals without any symptoms of cognitive impairment, who scored >27 points on the Mini-Mental State Examination. The participants (mean age, 72 years; 59% women underwent MRI of the brain with visual rating of microbleeds and WMH. Arterial stiffness was measured with carotid-femoral pulse wave velocity (cfPWV. Eight cognitive tests covering different cognitive domains were performed. Results: Microbleeds were detected in 12% and WMH in 31% of the participants. Mean (±standard deviation, SD cfPWV was 10.0 (±2.0 m/s. There was no association between the presence of microbleeds and arterial stiffness. There was a positive association between arterial stiffness and WMH independent of age or sex (odds ratio, 1.58; 95% confidence interval, 1.04-2.40, p 0.05. Cognitive performance was not associated with microbleeds, but individuals with WMH performed slightly worse than those without WMH on the Symbol Digit Modalities Test (mean ± SD, 35 ± 7.8 vs. 39 ± 8.1, p Conclusions: Arterial stiffness was not associated with the presence of cerebral microbleeds or cognitive function in cognitively healthy elderly. However, arterial stiffness was related to the presence of WMH, but the association was attenuated when multiple adjustments were made. There was a weak negative association between WMH and performance in one specific test of attention

  8. Land-Use and Land-Cover Mapping Using a Gradable Classification Method

    Directory of Open Access Journals (Sweden)

    Keigo Kitada

    2012-05-01

    Full Text Available Conventional spectral-based classification methods have significant limitations in the digital classification of urban land-use and land-cover classes from high-resolution remotely sensed data because of the lack of consideration given to the spatial properties of images. To recognize the complex distribution of urban features in high-resolution image data, texture information consisting of a group of pixels should be considered. Lacunarity is an index used to characterize different texture appearances. It is often reported that the land-use and land-cover in urban areas can be effectively classified using the lacunarity index with high-resolution images. However, the applicability of the maximum-likelihood approach for hybrid analysis has not been reported. A more effective approach that employs the original spectral data and lacunarity index can be expected to improve the accuracy of the classification. A new classification procedure referred to as “gradable classification method” is proposed in this study. This method improves the classification accuracy in incremental steps. The proposed classification approach integrates several classification maps created from original images and lacunarity maps, which consist of lacnarity values, to create a new classification map. The results of this study confirm the suitability of the gradable classification approach, which produced a higher overall accuracy (68% and kappa coefficient (0.64 than those (65% and 0.60, respectively obtained with the maximum-likelihood approach.

  9. Relation of cerebral small-vessel disease and brain atrophy to mild Parkinsonism in the elderly.

    Science.gov (United States)

    Reitz, Christiane; Trenkwalder, Claudia; Kretzschmar, Konrad; Roesler, Andreas; V Eckardstein, Arnold; Berger, Klaus

    2006-11-01

    The association between cerebral small-vessel disease, brain atrophy, and the risk and severity of mild parkinsonian signs (MPS) remains unclear. The objective of this study is to examine the effect of lacunar brain infarcts, cerebral white matter lesions (WMLs), and cortical atrophy on the risk and severity of MPS. This study is a cross-sectional community-based cohort study comprising 268 subjects, 65 to 83 years of age, residing in the Augsburg region of southern Germany, and without contraindications for magnetic resonance imaging (MRI) of the brain. Main outcome measures. Subcortical and periventricular WMLs, lacunar brain infarcts, and cortical atrophy determined using a standardized MRI protocol developed for the Rotterdam Scan Study and an established rating scale. MPS, assessed in a standardized neurological examination and based on the Unified Parkinson's Disease Rating Scale motor scale. Lacunar brain infarcts and large subcortical white matter lesions were associated with an elevated risk of resting tremor. More severe cortical atrophy was related to an increased risk of rigidity and bradykinesia. In a linear regression analysis relating each individual MRI measurement with the severity of MPS, the number of lacunar brain infarcts and the degree of brain atrophy were correlated with the severity of resting tremor, whereas the size of subcortical and periventricular WMLs was correlated with the severity of rigidity. A higher degree of brain atrophy was associated with increased severity of either cardinal sign. In our study, presence and volume of lacunar brain infarcts, cerebral WMLs, and cortical atrophy were associated with the risk as well as severity of MPS. Determining the presence of these brain changes using brain imaging might contribute to identify persons at risk for MPS.

  10. Impact of Non-Invasively Induced Motor Deficits on Tibial Cortical Properties in Mutant Lurcher Mice.

    Directory of Open Access Journals (Sweden)

    Alena Jindrová

    Full Text Available It has been shown that Lurcher mutant mice have significantly altered motor abilities, regarding their motor coordination and muscular strength because of olivorecebellar degeneration. We assessed the response of the cross-sectional geometry and lacuno-canalicular network properties of the tibial mid-diaphyseal cortical bone to motor differences between Lurcher and wild-type (WT male mice from the B6CBA strain. The first data set used in the cross-sectional geometry analysis consists of 16 mice of 4 months of age and 32 mice of 9 months of age. The second data set used in the lacunar-canalicular network analysis consists of 10 mice of 4 months of age. We compared two cross-sectional geometry and four lacunar-canalicular properties by I-region using the maximum and minimum second moment of area and anatomical orientation as well as H-regions using histological differences within a cross section. We identified inconsistent differences in the studied cross-sectional geometry properties between Lurcher and WT mice. The biggest significant difference between Lurcher and WT mice is found in the number of canaliculi, whereas in the other studied properties are only limited. Lurcher mice exhibit an increased number of canaliculi (p < 0.01 in all studied regions compared with the WT controls. The number of canaliculi is also negatively correlated with the distance from the centroid in the Lurcher and positively correlated in the WT mice. When the Lurcher and WT sample is pooled, the number of canaliculi and lacunar volume is increased in the posterior Imax region, and in addition, midcortical H-region exhibit lower number of canaliculi, lacuna to lacuna distance and increased lacunar volume. Our results indicate, that the importance of precise sample selection within cross sections in future studies is highlighted because of the histological heterogeneity of lacunar-canalicular network properties within the I-region and H-region in the mouse cortical

  11. 3D porous architecture of stacks of β-TCP granules compared with that of trabecular bone: a microCT, vector analysis and compression study

    Directory of Open Access Journals (Sweden)

    Daniel eCHAPPARD

    2015-10-01

    Full Text Available The 3D arrangement of porous granular biomaterials usable to fill bone defects has received little study. Granular biomaterials occupy 3D space when packed together in a manner that creates a porosity suitable for the invasion of vascular and bone cells. Granules of β-TCP were prepared with either 12.5 or 25g of β-TCP powder in the same volume of slurry. When the granules were placed in a test tube, this produced 3D stacks with a high (HP or low porosity (LP, respectively. Stacks of granules mimic the filling of a bone defect by a surgeon. The aim of this study was to compare the porosity of stacks of β-TCP granules with that of cores of trabecular bone. Biomechanical compression tests were done on the granules stacks. Bone cylinders were prepared from calf tibia plateau, constituted high density (HD blocks. Low density (LD blocks were harvested from aged cadaver tibias. Microcomputed tomography was used on the β-TCP granule stacks and the trabecular bone cores to determine porosity and specific surface. A vector projection algorithm was used to image porosity employing a frontal plane image which was constructed line by line from all images of a microCT stack. Stacks of HP granules had porosity (75.3 ± 0.4% and fractal lacunarity (0.043 ± 0.007 intermediate between that of HD (resp. 69.1 ± 6.4%, p<0.05 and 0.087 ± 0.045, p<0.05 and LD bones (resp. 88.8 ± 1.57% and 0.037 ± 0.014 but exhibited a higher surface density (5.56 ± 0.11 mm2/mm3 vs. 2.06 ± 0.26 for LD, p<0.05. LP granular arrangements created large pores coexisting with dense areas of material. Frontal plane analysis evidenced a more regular arrangement of β-TCP granules than bone trabeculae. Stacks of HP granules represent a scaffold that resembles trabecular bone in its porous microarchitecture.

  12. Biocomplexity and Fractality in the Search of Biomarkers of Aging and Pathology: Focus on Mitochondrial DNA and Alzheimer’s Disease

    Science.gov (United States)

    Zaia, Annamaria; Maponi, Pierluigi; Di Stefano, Giuseppina; Casoli, Tiziana

    2017-01-01

    Alzheimer’s disease (AD) represents one major health concern for our growing elderly population. It accounts for increasing impairment of cognitive capacity followed by loss of executive function in late stage. AD pathogenesis is multifaceted and difficult to pinpoint, and understanding AD etiology will be critical to effectively diagnose and treat the disease. An interesting hypothesis concerning AD development postulates a cause-effect relationship between accumulation of mitochondrial DNA (mtDNA) mutations and neurodegenerative changes associated with this pathology. Here we propose a computerized method for an easy and fast mtDNA mutations-based characterization of AD. The method has been built taking into account the complexity of living being and fractal properties of many anatomic and physiologic structures, including mtDNA. Dealing with mtDNA mutations as gaps in the nucleotide sequence, fractal lacunarity appears a suitable tool to differentiate between aging and AD. Therefore, Chaos Game Representation method has been used to display DNA fractal properties after adapting the algorithm to visualize also heteroplasmic mutations. Parameter β from our fractal lacunarity method, based on hyperbola model function, has been measured to quantitatively characterize AD on the basis of mtDNA mutations. Results from this pilot study to develop the method show that fractal lacunarity parameter β of mtDNA is statistically different in AD patients when compared to age-matched controls. Fractal lacunarity analysis represents a useful tool to analyze mtDNA mutations. Lacunarity parameter β is able to characterize individual mutation profile of mitochondrial genome and appears a promising index to discriminate between AD and aging. PMID:28197358

  13. Cognitive Function and Emotional Status of Middle-aged Chinese Hypertensive Patients Without Detectable White Matter Brain Lesions or Lacunar Infarctions

    Science.gov (United States)

    2006-01-01

    According to Baron & Kenny (1986), a significant interaction term signals a moderator of the relationship between EH and the specific cognitive ability...implications for cognition. J Cardiovasc Pharmacol, 16(2), 234-238. Baron , R. M., & Kenny , D. A. (1986). The moderator-mediator variable...The present results may not be generalizable beyond Chinese living in China with hypertension. In addition, self-report questionnaires were used

  14. 285例腔隙性脑梗死临床病因分析%Analysis on Clinical Causa Morbi of Lacunar Cerebral Infarction

    Institute of Scientific and Technical Information of China (English)

    葛萱; 葛敦钧

    2006-01-01

    [目的]探讨腔隙性脑梗死的发病原因及治疗.[方法]对285例腔隙性脑梗死患者给予胞二磷胆碱、葛根素治疗,对合并基础疾病的患者同时给予对症治疗.[结果]显效206例,好转79例,无1例死亡.[结论]积极治疗基础疾病可以有效预防和减少脑血管疾病的危险因素,避免腔隙性脑梗死的发生和再发生.

  15. Leaf anatomy of Gaillardia cabrerae (Asteraceae: Basic plan and comparative study of two contrasting habitat populations Anatomía foliar de Gaillardia cabrerae (Asteraceae: plan básico y estudio comparativo de dos poblaciones de hábitats contrastantes

    Directory of Open Access Journals (Sweden)

    Laura Beinticinco

    2011-06-01

    Full Text Available This study evaluates the leaf anatomy pattern of Gaillardia cabrerae Covas, an exclusive endemic camephyte from the Lihué Calel National Park, province of La Pampa, Argentina. Leaf cross sections and peelings of plants growing in two different populations were used to determine the basic leaf anatomy patterns and to estimate the influence of growth conditions in the two microhabitats. The analysis showed differences in epidermal cells area, stomata density and main diameter, lacunar parenchyma cells and central vascular bundle diameter and palisade parenchyma cells dimensions. These aspects might be reflecting environmental conditions of the populations, especially sun exposure and soil moisture. The results provide information on the relationship of the species to its environment, which could be used in the establishment of conservation policies.Gaillardia cabrerae Covas es un caméfito endémico del Parque Nacional Lihué Calel. En este estudio se evalúan características anatómicas de individuos de dos poblaciones provenientes de diferentes microhábitats de las Sierras de Lihué Calel. La información proporcionada es importante para entender las condiciones de vida de la especie y provee información inherente para establecer planes de conservación. Mediante cortes transversales y la técnica de peeling fue posible determinar el plan básico de la anatomía foliar y también verificar diferencias significativas en el área de células epidérmicas, densidad estomática, diámetro mayor de los estomas, diámetro de células del parénquima lagunar y del haz vascular central y en las dimensiones de las células del parénquima en empalizada. Las condiciones ambientales a las cuales estas poblaciones están sometidas, especialmente la exposición solar y la humedad del suelo son posibles factores que podrían explicar las diferencias detectadas en la anatomía foliar para ambas poblaciones.

  16. Brain CT-scan in acute stroke patients: silent infarcts and relation to outcome.

    Science.gov (United States)

    Corea, Francesco; Tambasco, Nicola; Luccioli, Roberto; Ciorba, Ettore; Parnetti, Lucilla; Gallai, Virgilio

    2002-01-01

    Silent infarcts (SIs) are common findings in stroke patients, but their clinical significance remains controversial. Aim of this study was to evaluate the prevalence of SI in consecutive stroke patients, characteristics, associated factors, and influence on in-hospital mortality. The population consisted of 191 patients, consecutively admitted for an acute stroke. Of 191 patients, 74 had SI on CT-scan. Silent infarcts were often multiple, right sided, lacunar. We found SI more frequently in older patients, smokers, with an ischemic stroke having small vessel disease as presumed cause. In our study SI were associated with ageing, smoke habit and lacunar stroke. Silent infarcts size influenced the rate of in-hospital mortality.

  17. Subtypes of ischemic cerebral circulation disorders at young age: diagnosis and treatment

    OpenAIRE

    Natalia Vyacheslavovna Pizova

    2012-01-01

    The paper shows that it is urgent to study stroke in young patients aged 15—45 years. In accordance with the TOAST classification, the author presents the major pathogenetic subtypes of ischemic stroke (IS): atherothromboembolic, cardioembolic, lacunar, that of other known and unknown etiology. The clinical picture and diagnostic principles of IS at young age are considered. Particular emphasis is laid on therapy for IS. It is pointed out that the leading therapy option in these patients is t...

  18. Microstructure and compressive mechanical properties of cortical bone in children with osteogenesis imperfecta treated with bisphosphonates compared with healthy children.

    Science.gov (United States)

    Imbert, Laurianne; Aurégan, Jean-Charles; Pernelle, Kélig; Hoc, Thierry

    2015-06-01

    Osteogenesis imperfecta (OI) is a genetic disorder characterized by a change in bone tissue quality, but little data are available to describe the factors involved at the macroscopic scale. To better understand the effect of microstructure alterations on the mechanical properties at the sample scale, we studied the structural and mechanical properties of six cortical bone samples from children with OI treated with bisphosphonates and compared them to the properties of three controls. Scanning electron microscopy, high resolution computed tomography and compression testing were used to assess these properties. More resorption cavities and a higher osteocyte lacunar density were observed in OI bone compared with controls. Moreover, a higher porosity was measured for OI bones along with lower macroscopic Young's modulus, yield stress and ultimate stress. The microstructure was impaired in OI bones; the higher porosity and osteocyte lacunar density negatively impacted the mechanical properties and made the bone more prone to fracture.

  19. Bipolar Disorder after Stroke in an Elderly Patient

    Directory of Open Access Journals (Sweden)

    Raquel Calvão de Melo

    2014-01-01

    Full Text Available The onset of bipolar disorder (BD secondary to a stroke event is a rare clinical entity. Although it may be related to specific regions of the brain, several other factors have been linked to its expression such as subcortical atrophy or chronic vascular burden. While precise locations and cerebral circuits involved in the bipolarity expression after stroke still need to be determined, their investigation represents an opportunity to study brain function and BD etiopathogenesis. We present a BD secondary to multiple subcortical biparietal lacunar infarctions, a lacunar infarction in left putamen and an ischemic lesion at the cerebral trunk evolving the right median portion, in a 65-year-old male patient who experienced manic, hypomanic, and depressive episodes, after 6, 10, and 16 months, respectively, of the cerebrovascular events.

  20. Relationships between personality traits, medial temporal lobe atrophy and white matter lesion in subjects suffering from mild cognitive impairment

    Directory of Open Access Journals (Sweden)

    Emmanuelle eDuron

    2014-07-01

    Full Text Available Mild Cognitive Impairment (MCI is a heterogeneous cognitive status that can be a prodromal stage of Alzheimer‘s disease (AD. It is particularly relevant to focus on prodromal stages of AD such as MCI, because pathophysiological abnormalities of AD start years before the dementia stage. Medial temporal lobe atrophy (MTL resulting from AD lesions and cerebrovascular lesions (i.e. white matter lesions (WML, lacunar strokes and strokes are often revealed concurrently on Magnetic Resonance Imaging (MRI in MCI subjects. Personality changes have been reported to be associated with MCI status and early AD. More specifically, an increase in neuroticism and a decrease in conscientiousness have been reported, suggesting that higher and lower scores, respectively in neuroticism and conscientiousness are associated with an increased risk of developing the disease. However, personality changes have not been studied concomitantly with pathological structural brain alterations detected on MRI in patients suffering from MCI. Therefore, the objective of the present study was to assess the relationship between MTL atrophy, WML, lacunar strokes and personality traits in such patients. The severity of WML was strongly associated with lower levels of conscientiousness and higher levels of neuroticism. Conversely, no association was detected between personality traits and the presence of lacunar strokes or MTL atrophy. Altogether, these results strongly suggest that personality changes occurring in a MCI population, at high risk of AD, are associated with WML, which can induce executive dysfunctions, rather than with MTL atrophy.

  1. Immunolocalization of loricrin in the maturing α-layer of normal and regenerating epidermis of the lizard Anolis carolinensis.

    Science.gov (United States)

    Alibardi, Lorenzo; Strasser, Bettina; Eckhart, Leopold

    2015-03-01

    Numerous corneous proteins are produced during the differentiation of the complex lizard epidermis, comprising hard β-layers and softer α-layers. In the present ultrastructural and immunocytochemical study, we have localized a homolog of the mammalian skin barrier protein loricrin in the skin of the green anole lizard (Anolis carolinensis). We used an antibody specific to the carboxyterminus of loricrin 1, a gene of the epidermal differentiation complex (EDC) of A. carolinensis. Lizard loricrin is present in the maturing α-layer (lacunar cells) of normal scale epidermis and in the accumulating corneocytes of the wound epidermis (lacunar cells) of the regenerating epidermis. The protein appears as a component of the α-layer but not of the β-layer. Lizard loricrin is diffused in the cytoplasm of pre-corneous α-keratinocytes but eventually concentrates in the packing corneous material of the maturing corneocytes of the α-layer (lacunar) in normal epidermis or in the wound epidermis of regenerating epidermis. The protein likely contributes to the composition and pliability of the corneous material but is not specifically accumulated on the corneous cell envelope (marginal layer) that is scarcely differentiated in these cells. The study contributes to the knowledge on the distribution of specific corneous proteins that give rise to the different material properties of α-layers versus β-layers in lizard epidermis.

  2. Evaluation of geometric features as biomarkers of diabetic retinopathy for characterizing the retinal vascular changes during the progression of diabetes.

    Science.gov (United States)

    Leontidis, Georgios; Al-Diri, Bashir; Wigdahl, Jeffrey; Hunter, Andrew

    2015-01-01

    Diabetic retinopathy (DR) has been widely studied and characterized. However, until now, it is unclear how different features, extracted from the retinal vasculature, can be associated with the progression of diabetes and therefore become biomarkers of DR. In this study, a comprehensive analysis is presented, in which four groups were created, using eighty fundus images from twenty patients, who have progressed to DR and they had no history of any other diseases (e.g. hypertension or glaucoma). The significance of the following features was evaluated: widths, angles, branching coefficient (BC), angle-to-BC ratio, standard deviations, means and medians of widths and angles, fractal dimension (FD), lacunarity and FD-to-lacunarity ratio, using a mixed model analysis of variance (ANOVA) design. All the features were measured from the same junctions of each patient, using an automated tool. The discriminative power of these features was evaluated, using decision trees and random forests classifiers. Cross validation and out-of-bag error were used to evaluate the classifiers' performance, calculating the area under the ROC curve (AUC) and the classification error. Widths, FD and FD-to-Lacunarity ratio were found to differ significantly. Random forests had a superior performance of 0.768 and 0.737 in the AUC for the two cases of classification, namely three-years-pre-DR/post-DR and two-years-pre-DR/post-DR respectively.

  3. Relationships between Personality Traits, Medial Temporal Lobe Atrophy, and White Matter Lesion in Subjects Suffering from Mild Cognitive Impairment

    Science.gov (United States)

    Duron, Emmanuelle; Vidal, Jean-Sébastien; Bounatiro, Samira; Ben Ahmed, Sana; Seux, Marie-Laure; Rigaud, Anne-Sophie; Hanon, Olivier; Viollet, Cécile; Epelbaum, Jacques; Martel, Guillaume

    2014-01-01

    Mild cognitive impairment (MCI) is a heterogeneous cognitive status that can be a prodromal stage of Alzheimer’s disease (AD). It is particularly relevant to focus on prodromal stages of AD such as MCI, because patho-physiological abnormalities of AD start years before the dementia stage. Medial temporal lobe (MTL) atrophy resulting from AD lesions and cerebrovascular lesions [i.e., white matter lesions (WML), lacunar strokes, and strokes] are often revealed concurrently on magnetic resonance imaging (MRI) in MCI subjects. Personality changes have been reported to be associated with MCI status and early AD. More specifically, an increase in neuroticism and a decrease in conscientiousness have been reported, suggesting that higher and lower scores, respectively, in neuroticism and conscientiousness are associated with an increased risk of developing the disease. However, personality changes have not been studied concomitantly with pathological structural brain alterations detected on MRI in patients suffering from MCI. Therefore, the objective of the present study was to assess the relationship between MTL atrophy, WML, lacunar strokes, and personality traits in such patients. The severity of WML was strongly associated with lower levels of conscientiousness and higher levels of neuroticism. Conversely, no association was detected between personality traits and the presence of lacunar strokes or MTL atrophy. Altogether, these results strongly suggest that personality changes occurring in a MCI population, at high risk of AD, are associated with WML, which can induce executive dysfunctions, rather than with MTL atrophy. PMID:25120483

  4. Evaluating differential nuclear DNA yield rates and osteocyte numbers among human bone tissue types: A synchrotron radiation micro-CT approach.

    Science.gov (United States)

    Andronowski, Janna M; Mundorff, Amy Z; Pratt, Isaac V; Davoren, Jon M; Cooper, David M L

    2017-05-01

    Molecular human identification has conventionally focused on DNA sampling from dense, weight-bearing cortical bone tissue, typically from femora or tibiae. A comparison of skeletal elements from three contemporary individuals demonstrated that elements with high quantities of cancellous bone yielded nuclear DNA at the highest rates, suggesting that preferentially sampling cortical bone may be suboptimal (Mundorff & Davoren, 2014). Despite these findings, the reason for the differential DNA yields between cortical and cancellous bone tissues remains unknown. The primary goal of this work is to ascertain whether differences in bone microstructure can be used to explain differential nuclear DNA yield among bone tissue types observed by Mundorff and Davoren (2014), with a focus on osteocytes and the three-dimensional (3D) quantification of their associated lacunae. Osteocytes and other bone cells are recognized to house DNA in bone tissue, thus examining the density of their lacunae may explain why nuclear DNA yield rates differ among bone tissue types. Lacunae were visualized and quantified using synchrotron radiation-based micro-Computed Tomographic imaging (SR micro-CT). Volumes of interest (VOIs) from cortical and cancellous bone tissues (n=129) were comparatively analyzed from the three skeletons sampled for Mundorff and Davoren's (2014) study. Analyses tested the primary hypothesis that the abundance and density of osteocytes (inferred from their lacunar spaces) vary between cortical and cancellous bone tissue types. Results demonstrated that osteocyte lacunar abundance and density vary between cortical and cancellous bone tissue types, with cortical bone VOIs containing a higher lacunar abundance and density. We found that the osteocyte lacunar density values are independent of nuclear DNA yield, suggesting an alternative explanation for the higher nuclear DNA yields from bones with greater quantities of cancellous bone tissue. The use of SR micro-CT allowed for

  5. 腔隙性脑梗死患者脑微出血与循环内皮微粒的相关性研究%Correlation between cerebral microbleeds and circulating endothelial microparticles in lacunar stroke patients

    Institute of Scientific and Technical Information of China (English)

    孔德燕

    2015-01-01

    目的 探讨腔隙性脑梗死患者脑微出血(CMB)与血浆内皮微粒(EMP)的关系.方法 选择首次发病3个月后的腔隙性脑梗死患者84例,根据磁敏感检测结果分为CMB组33例和无CMB组51例,收集2组患者的临床基线资料,并通过流式细胞仪检测其血浆CD31+/CD42-EMP水平.结果 CMB组EMP水平明显高于无CMB组[(451.93±94.46)×106/Lvs (310.93±55.47)×106/L,P=0.000].CMB严重程度与EMP呈正相关(r=0.817,P=0.000).二分类logistic回归分析显示,在控制了年龄、高血压、纤维蛋白原等混杂因素影响后,EMP升高仍是影响CMB发病的危险因素.结论血浆EMP升高是影响CMB发病的独立危险因素,EMP检测可作为临床预测脑梗死患者是否合并CMB的指标.

  6. Analysis on the correlation of cerebral microbleeds and post-stroke depression in lacunar stroke%脑微出血与腔隙性脑梗死患者卒中后抑郁的相关性分析

    Institute of Scientific and Technical Information of China (English)

    牛晓波; 缑元冲; 郭旭亮

    2015-01-01

    目的 探讨脑微出血(CMB)与腔隙性脑梗死(LI)患者卒中后抑郁的相关性.方法 选择腔隙性脑梗死患者216例,进行老年抑郁量表(GDS)评测,≥5分为存在抑郁,分为抑郁组和无抑郁组.记录两组CMB总数量及脑叶CMB、深部CMB、幕下CMB及左右半球CMB数量,分析两组CMB数量与部位、人口学资料、临床资料及影像学资料的关系.结果 两组在脑叶CMB及左半球CMB、女性、美国国立卫生研究院卒中量表(NIHSS)评分、脑白质病变(WML)、深部LI及左半球LI等方面比较差异有统计学意义(P<0.05).多因素分析提示脑叶CMB是卒中后抑郁(PSD)的独立危险因素(OR=5.843,P=0.040).结论 脑叶CMB及左半球CMB为PSD危险因素,其他危险因素包括女性、较严重的神经功能缺损、脑白质病变、LI特别是深部及左半球LI.

  7. A controlled observation on depression and P300 potentials in 60 patients with lacunar infarct%腔隙性脑梗死60例抑郁情绪及P300电位的对照观察

    Institute of Scientific and Technical Information of China (English)

    张朝辉; 宋景贵; 王夏红; 穆俊林

    2006-01-01

    目的探讨腔隙性脑梗死(LI)患者的抑郁情绪和P300电位变化及其临床价值.方法对60例LI患者和59例健康者分别进行了P300电位测定和抑郁量表评定,并将2组结果加以比较.结果与对照组相比,LI组P300电位成分中N2、P3波潜伏期延长和P3波幅降低,其差异具有显著性(P<0.05或P<0.01).抑郁量表评定各因子分2组相比存在显著性差异(P<0.01).结论部分LI患者存在抑郁情绪和认知功能障碍,P300电位可作为评价其认知功能的指标应用于临床.

  8. Study Drugs

    Science.gov (United States)

    ... study drugs: amphetamines like Adderall, Dexedrine, or Vyvanse methylphenidates like Ritalin or Concerta Most people get study ... How Much Sleep Do I Need? Prescription Drug Abuse How to Make Homework Less Work Organizing Schoolwork & ...

  9. Biofeasibility Study.

    Science.gov (United States)

    Chaparian, Michael

    1995-01-01

    Discusses the use of bioremediation as a method for disposing of contaminants by exploiting natural biodegradation processes. The process of conducting a biofeasibility study and a case study are reviewed. (LZ)

  10. Study of nanosensor systems for hypertension associated cerebrovascular and cardiovascular disorders

    Science.gov (United States)

    Ramasamy, Mouli; Varadan, Vijay K.

    2015-04-01

    Hypertension and hypertension associated cerebrovascular and cardiovascular diseases are on a rise. At-least 970 million people in the world and Seventy percent of the American adults are affected by high blood pressure, also known as hypertension. Even though blood pressure monitoring systems are readily available, the number of people being affected has been increasing. Most of the blood pressure monitoring systems require cumbersome approaches. Even the noninvasive techniques have not lowered the number of people affected nor did at-least increase the user base of these systems. Uncontrolled or untreated hypertension may lead to various cerebrovascular disorders including stroke, hypertensive crisis, lacunar infarcts intracerebral damage, microaneurysm, and cardiovascular disorders including heart failure, myocardial infraction, and ischemic heart disease. Hypertension is rated as the one of the most important causes of premature death in spite of the technical advances in biomedical technology. This paper briefs a review of the widely adopted blood pressure monitoring methods, research techniques, and finally, proposes a concept of implementing nanosensors and wireless communication for real time non-invasive blood pressure monitoring.

  11. Clinical symptoms and risk factors in cerebral microangiopathy patients.

    Directory of Open Access Journals (Sweden)

    Sandra Okroglic

    Full Text Available OBJECTIVE: Although the clinical manifestation and risk factors of cerebral microangiopathy (CM remain unclear, the number of diagnoses is increasing. Hence, patterns of association among lesion topography and severity, clinical symptoms and demographic and disease risk factors were investigated retrospectively in a cohort of CM patients. METHODS: Patients treated at the Department of Neurology, University of Bonn for CM (n = 223; 98m, 125f; aged 77.32±9.09 from 2005 to 2010 were retrospectively enrolled. Clinical symptoms, blood chemistry, potential risk factors, demographic data and ratings of vascular pathology in the brain based on the Wahlund scale were analyzed using Pearson's chi square test and one-way ANOVA. RESULTS: Progressive cognitive decline (38.1%, gait apraxia (27.8%, stroke-related symptoms and seizures (24.2%, TIA-symptoms (22% and vertigo (17% were frequent symptoms within the study population. Frontal lobe WMLs/lacunar infarcts led to more frequent presentation of progressive cognitive decline, seizures, gait apraxia, stroke-related symptoms, TIA, vertigo and incontinence. Parietooccipital WMLs/lacunar infarcts were related to higher frequencies of TIA, seizures and incontinence. Basal ganglia WMLs/lacunar infarcts were seen in patients with more complaints of gait apraxia, vertigo and incontinence. Age (p = .012, arterial hypertension (p<.000, obesity (p<.000 and cerebral macroangiopathy (p = .018 were positively related to cerebral lesion load. For increased glucose level, homocysteine, CRP and D-Dimers there was no association. CONCLUSION: This underlines the association of CM with neurological symptoms upon admission in a topographical manner. Seizures and vertigo are symptoms of CM which may have been missed in previous studies. In addition to confirming known risk factors such as aging and arterial hypertension, obesity appears to increase the risk as well. Since the incidence of CM is increasing, future

  12. Studying Zooarchaeology

    Science.gov (United States)

    Moore, Molly; Wolf, Deborah; Butler, Virginia L.

    2012-01-01

    Children often associate the study of bones with dinosaurs or crime scenes. This unit introduces students to "zooarchaeology," the study of animal remains from archaeological sites. Students in grades 3-5 engage in hands-on activities examining bones, shells, and other "hard parts" of animals. They use their observations as a starting point for…

  13. Nonlinear analysis of drainage systems to examine surface deformation: an example from Potwar Plateau (Northern Pakistan

    Directory of Open Access Journals (Sweden)

    F. Shahzad

    2010-03-01

    Full Text Available We devise a procedure in order to characterize the relative vulnerability of the Earth's surface to tectonic deformation using the geometrical characteristics of drainage systems. The present study focuses on the nonlinear analysis of drainage networks extracted from Digital Elevation Models in order to localize areas strongly influenced by tectonics. We test this approach on the Potwar Plateau in northern Pakistan. This area is regularly affected by damaging earthquakes. Conventional studies cannot pinpoint the zones at risk, as the whole region is characterized by a sparse and diffuse seismicity. Our approach is based on the fact that rivers tend to linearize under tectonic forcing. Thus, the low fractal dimensions of the Swan, Indus and Jehlum Rivers are attributed to neotectonic activity. A detailed textural analysis is carried out to investigate the linearization, heterogeneity and connectivity of the drainage patterns. These textural aspects are quantified using the fractal dimension, as well as lacunarity and succolarity analysis. These three methods are complimentary in nature, i.e. objects with similar fractal dimensions can be distinguished further with lacunarity and/or succolarity analysis. We generate maps of fractal dimensions, lacunarity and succolarity values using a sliding window of 2.5 arc minutes by 2.5 arc minutes (2.5'×2.5'. These maps are then interpreted in terms of land surface vulnerability to tectonics. This approach allowed us to localize several zones where the drainage system is highly structurally controlled on the Potwar Plateau. The region located between Muree and Muzaffarabad is found to be prone to destructive events whereas the area westward from the Indus seems relatively unaffected. We conclude that a nonlinear analysis of the drainage system is an efficient additional tool to locate areas likely to be affected by massive destructing events affecting the Earth's surface and therefore threaten human

  14. Initial Study

    DEFF Research Database (Denmark)

    Torp, Kristian

    2009-01-01

    Congestion is a major problem in most cities and the problem is growing (Quiroga, 2000) (Faghri & Hamad, 2002). When the congestion level is increased the drivers notice this as delays in the traffic (Taylor, Woolley, & Zito, 2000), i.e., the travel time for the individual driver is simply...... increased. In the initial study presented here, the time it takes to pass an intersection is studied in details. Two major signal-controlled four-way intersections in the center of the city Aalborg are studied in details to estimate the congestion levels in these intersections, based on the time it takes...

  15. Subtypes of ischemic cerebral circulation disorders at young age: diagnosis and treatment

    Directory of Open Access Journals (Sweden)

    Natalia Vyacheslavovna Pizova

    2012-01-01

    Full Text Available The paper shows that it is urgent to study stroke in young patients aged 15—45 years. In accordance with the TOAST classification, the author presents the major pathogenetic subtypes of ischemic stroke (IS: atherothromboembolic, cardioembolic, lacunar, that of other known and unknown etiology. The clinical picture and diagnostic principles of IS at young age are considered. Particular emphasis is laid on therapy for IS. It is pointed out that the leading therapy option in these patients is thrombolysis; intravenous recombinant tissue plasminogen activator is more frequently used; oral anticoagulants and antiplatelet agents are certain to prescribe.

  16. Actuarial Studies

    Data.gov (United States)

    U.S. Department of Health & Human Services — The Office of the Actuary in the Centers for Medicare and Medicaid Services (CMS) from time to time conducts studies on various aspects of the Medicare and Medicaid...

  17. Studying Sideways

    DEFF Research Database (Denmark)

    Plesner, Ursula

    2011-01-01

    inequalities in relation to the people we study. This article argues that not all types of social scientific research interviews benefit from an à priori problematization of power and control, ethics and equality, or emancipation. From a constructivist perspective, the article seeks to displace...... the methodological concern with power related to the ideas of studying up or down and introduce another set of concerns in relation to producing good empirical material when we “study sideways.” The argument is based on analyses of interview situations from a concrete research project, where researcher...... and researched share professional background to some degree, where negotiations replace a researcher-imposed dialogue, and where the circulation of shared or common concepts messes up an orderly division between researchers’ vocabulary and interviewees’ vocabularies. It is proposed that when we study sideways...

  18. Floodplain Study

    Data.gov (United States)

    Montgomery County of Maryland — The purpose of a floodplain study is to establish the 100-year floodplain limits within or near a development in order to preserve the natural resources within the...

  19. Writing Study and Grammar Study

    Institute of Scientific and Technical Information of China (English)

    马青

    2013-01-01

    This study is undertaken to describe,classify and analyze the problems in Chinese college students’ writing of CET-4 through contrastive analysis,statistical analysis and error analysis.The main problems appearing in CET-4 writing are the wrong usage of words,sentence structures and the lack of coherence.Meanwhile it proves grammar study plays an important and basic role in CET-4 writing.

  20. Studying CO

    NARCIS (Netherlands)

    Boullenger, B.; Verdel, A.; Paap, B.; Thorbecke, J.; Draganov, D.

    2014-01-01

    Seismic interferometry applied to ambient-noise measurements allows the retrieval of the seismic response between pairs of receivers. We studied ambient-noise seismic interferometry (ANSI) to retrieve time-lapse reflection responses from a reservoir during CO2 geologic sequestration, usin

  1. Study Strategies

    DEFF Research Database (Denmark)

    Nielsen, Camilla Kirketerp; Noer, Vibeke Røn

    2016-01-01

    and theory forms the basis of the research. Veterinary students have been followed through alternating learning contexts referring to both the scholastic academic classrooms and workplaces in commercial pig herds as well as to group work and game-based situations in a mandatory master course - ”the pig......-disciplinary aspects on elements in the professionalisation process of nurse students and veterinary students. An inherent alternation between different learning rooms – scholastic academic classrooms and professional workplaces - is central to the profession-oriented educations. Educational structure and time...... theory and practice. Further, most empirical studies have been conducted in the part of the educations taking place in the work-oriented learning contexts (practice). The paper is based on two independent case-studies referring to the educational field of future nurses and future veterinarians. Both...

  2. Study protocol

    DEFF Research Database (Denmark)

    Thorsteinsson, Troels; Helms, Anne Sofie; Adamsen, Lis;

    2013-01-01

    in the intervention program. The physical and social intervention examines the effect of early, structured, individualized, and continuous physical activity from diagnosis throughout the treatment period. The patients are tested at diagnosis, at 3 and 6 months after diagnosis, and one year after the cessation...... to interaction with peers.Methods/design: The RESPECT study is a nationwide population-based prospective, controlled, mixed-methods intervention study looking at children aged 6-18 years newly diagnosed with cancer in eastern Denmark (n = 120) and a matched control group in western Denmark (n = 120). RESPECT....... Secondary endpoints are quality of life measured by validated questionnaires and interviews, and physical performance. RESPECT includes a multimodal intervention program, including ambassador-facilitated educational, physical, and social interventions. The educational intervention includes an educational...

  3. Invisibility Studies

    DEFF Research Database (Denmark)

    Invisibility Studies explores current changes in the relationship between what we consider visible and what invisible in different areas of contemporary culture. Contributions trace how these changes make their marks on various cultural fields and investigate the cultural significance of these de...... this conversation by bringing together scholars across the fields of architectural history and theory, art, film and literature, philosophy, cultural theory and contemporary anthropology as well as featuring work by a collective of artists.......Invisibility Studies explores current changes in the relationship between what we consider visible and what invisible in different areas of contemporary culture. Contributions trace how these changes make their marks on various cultural fields and investigate the cultural significance...

  4. Cerebral Microbleeds Are Associated with Worse Cognitive Function in the Nondemented Elderly with Small Vessel Disease

    Directory of Open Access Journals (Sweden)

    Kazuo Yamashiro

    2014-12-01

    Full Text Available Background: Cerebral small vessel disease (SVD is a leading cause of cognitive decline in the elderly. Cerebral microbleeds (CMBs have emerged as an important manifestation of cerebral SVD, in addition to lacunar infarcts and white matter lesions (WMLs. We investigated whether the presence and location of CMBs in elderly subjects were associated with cognitive function, independent of lacunar infarcts and WMLs. Methods: One hundred and forty-eight nondemented elderly with SVD, defined as the presence of lacunar infarcts and/or WMLs on magnetic resonance imaging (MRI, were studied. Executive function and global cognition were assessed by the Frontal Assessment Battery (FAB and Mini-Mental State Examination (MMSE, respectively. The differences in the scores for the FAB and MMSE between CMB-positive and CMB-negative subjects were calculated after adjusting for possible confounders. Results: The mean age of the subjects was 72.4 w 8.6 years. CMBs were detected in 48 subjects (32%, with a mean number of CMBs per subject of 1.6 (range 0-31. Among CMB-positive subjects, 42 (87.5% had CMBs in deep or infratentorial regions with or without lobar CMBs, and 6 (12.5% had CMBs in strictly lobar regions. The presence of CMBs was significantly associated with FAB and MMSE scores after adjustment for age, years of education, brain volume and the presence of lacunar infarcts (for the FAB or severe WMLs (for the MMSE. The presence of CMBs in the basal ganglia, in the thalamus or in the lobar regions was associated with FAB scores, while that in the lobar regions was associated with MMSE scores. However, there was no association between CMBs in the infratentorial regions and cognitive parameters. Conclusions: In nondemented elderly with SVD on MRI, the presence of CMBs was independently associated with worse executive and global cognitive functions. CMBs seemed to reflect hypertensive microangiopathy in this population, and CMBs in specific areas may play an

  5. Security Studies

    OpenAIRE

    ,

    2005-01-01

    Security Studies has firmly established itself as a leading journal on international security issues. The journal publishes theoretical, historical and policy-oriented articles on the causes and consequences of war, and the sources and conditions of peace. The journal has published articles on balancing vs. bandwagoning, deterrence in enduring rivalries, the Domino theory, nuclear weapons proliferation, civil-military relations, political reforms in China, strategic culture in Asia and the P...

  6. New insights into mechanisms of small vessel disease stroke from genetics.

    Science.gov (United States)

    Tan, Rhea; Traylor, Matthew; Rutten-Jacobs, Loes; Markus, Hugh

    2017-04-01

    Cerebral small vessel disease (SVD) is a common cause of lacunar strokes, vascular cognitive impairment (VCI) and vascular dementia. SVD is thought to result in reduced cerebral blood flow, impaired cerebral autoregulation and increased blood-brain barrier (BBB) permeability. However, the molecular mechanisms underlying SVD are incompletely understood. Recent studies in monogenic forms of SVD, such as cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL), and 'sporadic' SVD have shed light on possible disease mechanisms in SVD. Proteomic and biochemical studies in post-mortem monogenic SVD patients, as well as in animal models of monogenic disease have suggested that disease pathways are shared between different types of monogenic disease, often involving the impairment of extracellular matrix (ECM) function. In addition, genetic studies in 'sporadic' SVD have also shown that the disease is highly heritable, particularly among young-onset stroke patients, and that common variants in monogenic disease genes may contribute to disease processes in some SVD subtypes. Genetic studies in sporadic lacunar stroke patients have also suggested distinct genetic mechanisms between subtypes of SVD. Genome-wide association studies (GWAS) have also shed light on other potential disease mechanisms that may be shared with other diseases involving the white matter, or with pathways implicated in monogenic disease. This review brings together recent data from studies in monogenic SVD and genetic studies in 'sporadic' SVD. It aims to show how these provide new insights into the pathogenesis of SVD, and highlights the possible convergence of disease mechanisms in monogenic and sporadic SVD.

  7. Study protocol

    DEFF Research Database (Denmark)

    Madsen, Helle Østergaard; Dam, Ole Henrik; Hageman, Ida

    2012-01-01

    and demographically matched control respondents will be contacted in a similar manner the subsequent winter season. The Seasonal Pattern Assessment Questionnaire rates seasonal variation within the six items: sleep, appetite, social activity, mood, energy and body weight. The Seasonal Pattern Assessment Questionnaire......INTRODUCTION: People with seasonal affective disorder (SAD) experience recurrent seasonal fluctuations in energy, mood and appetite. Retinal light exposure is suggested to play an important role in the pathogenesis and treatment of SAD. The aim of the study is to determine the prevalence of SAD...

  8. Complementary Study

    Science.gov (United States)

    Yamada, H.

    2009-02-01

    In this lecture, it is emphasized that sufficient resolution of scientific issues for a fusion energy reactor can be given by complementary studies. Key scientific issues for a fusion energy reactor and ITER addressed by a complementary study in the Large Helical Device (LHD) are discussed. It should be noted that ITER is definitely a necessary condition but not a sufficient condition. Helical systems including stellarators and heliotrons are defined as alternative concepts. These approaches also aim at a fusion energy reactor based on their own concept and simultaneously benefit progress in tokamaks, more specifically ITER itself. The exact science to manage a 3-D geometry has been being developed in helical systems. A physical model with much accuracy and breadth will demonstrate its applicability to ITER. Topics to validate "complementary" approaches such as 3-D equilibrium, interchange MHD mode, control of radial electric field & structure formation, dynamics of a magnetic island, density limit and edge plasmas are discussed. Complementary is not Supplementary. ITER is complementary to development of a helical fusion energy reactor as well. Complementary approaches transcend existing disciplinary horizons and enable big challenges.

  9. SOCIOLOGICAL STUDIES

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    PAPER Post-Sociology: Exploration and Reflection Xie Lizhong Abstract: "Post-Sociology" refers to a new perspective which is different from tradi- tional perspectives of social studies. "Post-Social History" and "Pluralistic Discourse Analysis" could be seen as its two specific examples. "Discourse Constructivism" and "Pluralism" are the two core concepts of "Post-Sociology". That encouraging people to realize that all "social reality" including our experiences, thoughts and speech are just a "discoursive reality" constructed by social actors under the guidance and constraints of certain discourse system, is the major significance of "PostSociology". Some critics on "Post-Sociology" are misunderstandings, while others couldn't stand to strict analysis.

  10. Conceptual study

    Energy Technology Data Exchange (ETDEWEB)

    Harty, H.

    1978-09-01

    This appendix is a compendium of topical reports prepared for the Hanford Nuclear Energy Center: Status Report: Conceptual Fuel Cycle Studies for the Hanford Nuclear Energy Center; Selection of Heat Disposal Methods for a Hanford Nuclear Energy Center; Station Service Power Supply for a Hanford Nuclear Energy Center (HNEC); Impact of a Hanford Nuclear Energy Center on Ground Level Fog and Humidity; A Review of Potential Technology for the Seismic Characterization of Nuclear Energy Centers; Reliability of Generation at a Hanford Nuclear Energy Center (HNEC); Meteorological Evaluation of Multiple Reactor Contamination Probabilities for a Hanford Nuclear Energy Center; Electric Power Transmission for a Hanford Nuclear Energy Center (HNEC); The Impact of a Hanford Nuclear Energy Center on Cloudiness and Insolation; and A Licensing Review for an HNEC.

  11. Nutritional studies

    Science.gov (United States)

    Rambaut, P. C.; Smith, M. C., Jr.; Wheeler, H. O.

    1975-01-01

    Detailed metabolic studies were conducted of the Apollo 16 and Apollo 17 flight crews, and the results are presented in tabular form. Intake and absorption data are also included. Apollo nutrient intakes were found to be characteristically hypocaloric. Estimates of body composition changes from metabolic balance data, from preflight and postflight weights and volumes, and from total body water and potassium provide no evidence for diminished caloric requirements during a flight. As observed during the Gemini Program and during periods of bed rest, measurements of bone density and metabolic balance confirm a tendency toward loss of skeletal tissue in weightlessness. No evidence exists that any inflight metabolic anomaly, including hypokalemia, was induced by marginal or deficient nutrient intakes. In general, the Apollo crewmen were well nourished and exhibited normal gastroenterological functions, although appetite was somewhat diminished and the organoleptic response to food was somewhat modified during flight.

  12. Clinical Studies

    DEFF Research Database (Denmark)

    Pallesen, Ulla

    and repair? Have new materials improved longevity? Are there still clinical and material problems to be solved? And what has the highest impact on longevity of posterior resin restorations – the material, the dentist, the patient or the tooth? These matters will be discussed on the basis of the literature......Within the last 25 years composite resin materials have in many countries successively replaced amalgam as a restorative for posterior teeth. Resin materials and bonding systems are continuously being improved by the manufactures, adhesive procedures are now included in the curriculum of most...... universities and practicing dentists restore millions of teeth throughout the World with composite resin materials. Do we know enough about the clinical performance of these restorations over time? Numerous in vitro studies are being published on resin materials and adhesion, some of them attempting to imitate...

  13. Vascular organization of the hystricomorph placenta: a comparative study in the agouti, capybara, guinea pig, paca and rock cavy.

    Science.gov (United States)

    Miglino, M A; Carter, A M; Ambrosio, C E; Bonatelli, M; De Oliveira, M F; Dos Santos Ferraz, R H; Rodrigues, R F; Santos, T C

    2004-05-01

    The placental vasculature of five hystricomorph rodents was examined by latex injection of the blood vessels, immunohistochemistry and scanning electron microscopy of vessel casts. The pattern of branching of the vessels is described at the level of fine structure. The placenta is divided into lobes separated by interlobular trophoblast. Fetal arteries course through the interlobular areas and give rise to capillaries from which blood drains into veins at the centre of the lobes. Maternal blood reaches the placenta through spiral arteries that pass around the perimeter of the subplacenta. They supply large maternal blood sinuses, lined by trophoblast, which run through the interlobular areas and into the centre of the lobes. Here they supply fine channels that run parallel to the fetal capillaries, so that maternal blood flows from the centre of the lobe to the periphery. This arrangement provides the morphological basis for countercurrent exchange. The maternal channels of the labyrinth drain into spaces formed by the latticework of the interlobular trophoblast and thence through venous lacunae to a basal venous lacunar ring. The subplacenta is supplied by a single fetal artery. The vessels within the subplacenta pursue a tortuous course with dilatations and constrictions as in an endocrine gland.

  14. Systems Studies

    Energy Technology Data Exchange (ETDEWEB)

    Graham, R.L.

    1998-03-17

    The Systems Studies Activity had two objectives: (1) to investigate nontechnical barriers to the deployment of biomass production and supply systems and (2) to enhance and extend existing systems models of bioenergy supply and use. For the first objective, the Activity focused on existing bioenergy markets. Four projects were undertaken: a comparative analysis of bioenergy in Sweden and Austria; a one-day workshop on nontechnical barriers jointly supported by the Production Systems Activity; the development and testing of a framework for analyzing barriers and drivers to bioenergy markets; and surveys of wood pellet users in Sweden, Austria and the US. For the second objective, two projects were undertaken. First, the Activity worked with the Integrated BioEnergy Systems (TBS) Activity of TEA Bioenergy Task XIII to enhance the BioEnergy Assessment Model (BEAM). This model is documented in the final report of the IBS Activity. The Systems Studies Activity contributed to enhancing the feedstock portion of the model by developing a coherent set of willow, poplar, and switchgrass production modules relevant to both the US and the UK. The Activity also developed a pretreatment module for switchgrass. Second, the Activity sponsored a three-day workshop on modeling bioenergy systems with the objectives of providing an overview of the types of models used to evaluate bioenergy and promoting communication among bioenergy modelers. There were nine guest speakers addressing different types of models used to evaluate different aspects of bioenergy, ranging from technoeconomic models based on the ASPEN software to linear programming models to develop feedstock supply curves for the US. The papers from this workshop have been submitted to Biomass and Bioenergy and are under editorial review.

  15. Analysis of the XRCC1 gene as a modifier of the cerebral response in ischemic stroke

    Directory of Open Access Journals (Sweden)

    Juo Suh-Hang H

    2006-11-01

    Full Text Available Abstract Background Although there have been studies of the genetic risk factors in the development of stroke, there have been few investigations of role of genes in the cerebral response to ischemia. The brain responds to ischemia in a series of reactions that ultimately influence the volume of a stroke that, in general, correlates with disability. We hypothesize that polymorphisms in genes encoding proteins involved in these reactions could act as modifiers of this response and impact stroke volume. One of the pathways participating in the cerebral ischemic response involves reactive oxygen species which can cause oxidative damage to nucleic acids. DNA repair mechanisms are in place to protect against such damage and imply a role for DNA repair genes in the response of the brain to ischemia and are potential candidate genes for further investigation. Methods We studied two common polymorphisms in the DNA repair gene, XRCC1, C26304T and G28152A, in 134 well characterized patients with non lacunar ischemic strokes. We also performed a case control association study with 113 control patients to assess whether these variants represent risk factors in the development of ischemic stroke. Results Independent of etiology, the "T" allele of the C26304T polymorphism is significantly associated with larger stroke volumes (T-test analysis, p Conclusion Our study suggests a major gene effect of the "T" allele of the C26304T polymorphism modulating the cerebral response to ischemia in non lacunar ischemic stroke.

  16. A case of thalamic hemorrhage-induced diaschisis

    Institute of Scientific and Technical Information of China (English)

    Gang Yao; Yuhong Man; Xijing Mao; Tingmin Yu

    2011-01-01

    Diaschisis refers to a disturbance (inhibition or facilitation) of function in an area remote from the site of a primary brain lesion. Previous studies have confirmed that regional cerebral blood flow and metabolism are noticeably decreased in an infarct region. Transient excessive perfusion appears in the ischemic penumbra, and diaschisis occurs in an area remote from the lesion site, showing decreased regional cerebral blood flow and metabolism. Mirror diaschisis refers to a decrease in oxygen metabolism and blood flow in the "mirror image area" to the infarct regions in the contralateral hemisphere. In this study, a patient with right thalamic hemorrhage was affected with right arm and leg numbness. At 4 months before onset, magnetic resonance imaging of the head demonstrated lacunar infarcts in the left thalamus; therefore the right arm and leg numbness was not associated with lacunar infarcts in the left thalamus. At 8 days following onset, magnetic resonance imaging reexamination did not reveal the focus that could induce right arm and leg numbness and weakness. Thus, it is suggested in this study that the onset of this disease can be explained by mirror diaschisis. That is, right thalamic hemorrhage leads to decreased blood flow and metabolic disturbance in the contralateral thalamus, resulting in right arm and leg numbness.

  17. Fractal analysis and Gray level co-occurrence matrix method for evaluation of reperfusion injury in kidney medulla.

    Science.gov (United States)

    Pantic, Igor; Nesic, Zorica; Paunovic Pantic, Jovana; Radojević-Škodrić, Sanja; Cetkovic, Mila; Basta Jovanovic, Gordana

    2016-05-21

    Fractal analysis and Gray level co-occurrence matrix method represent two novel mathematical algorithms commonly used in medical sciences as potential parts of computer-aided diagnostic systems. In this study, we tested the ability of these methods to discriminate the kidney medullar tissue suffering from reperfusion injury, from normal tissue. A total of 320 digital micrographs of Periodic acid-Schiff (PAS) - stained kidney medulla from 16 Wistar albino mice (20 per animal), were analyzed using National Institutes of Health ImageJ software (NIH, Bethesda, MD) and its plugins. 160 micrographs were obtained from the experimental group with induced reperfusion injury, and another 160 were obtained from the controls. For each micrograph we calculated the values of fractal dimension, lacunarity, as well as five GLCM features: angular second moment, entropy, inverse difference moment, GLCM contrast, and GLCM correlation. Discriminatory value of the parameters was tested using receiver operating characteristic (ROC) analysis, by measuring the area below ROC curve. The results indicate that certain features of GLCM algorithm have excellent discriminatory ability in evaluation of damaged kidney tissue. Fractal dimension and lacunarity as parameters of fractal analysis also had a relatively good discriminatory value in differentiation of injured from the normal tissue. Both methods have potentially promising application in future design of novel techniques applicable in cell physiology, histology and pathology.

  18. The role of calcium and nicotinic acid adenine dinucleotide phosphate (NAADP) in human osteoclast formation and resorption.

    Science.gov (United States)

    Cheng, X; Hookway, E S; Kashima, T; Oppermann, U; Galione, A; Athanasou, N A

    2015-01-01

    Osteoclasts are specialised bone resorbing cells which form by fusion of circulating mononuclear phagocyte precursors. Bone resorption results in the release of large amounts of calcium into the extracellular fluid (ECF), but it is not certain whether changes in extracellular calcium concentration [Ca(2+)]e influence osteoclast formation and resorption. In this study, we sought to determine the effect of [Ca(2+)]e and NAADP, a potent calcium mobilising messenger that induces calcium uptake, on human osteoclast formation and resorption. CD14+ human monocytes were cultured with M-CSF and RANKL in the presence of different concentrations of calcium and NAADP and the effect on osteoclast formation and resorption evaluated. We found that the number of TRAP+ multinucleated cells and the extent of lacunar resorption were reduced when there was an increase in extracellular calcium and NAADP. This was associated with a decrease in RANK mRNA expression by CD14+ cells. At high concentrations (20 mM) of [Ca(2+)]e mature osteoclast resorption activity remained unaltered relative to control cultures. Our findings indicate that osteoclast formation is inhibited by a rise in [Ca(2+)]e and that RANK expression by mononuclear phagocyte osteoclast precursors is also [Ca(2+)]e dependent. Changes in NAADP also influence osteoclast formation, suggesting a role for this molecule in calcium handling. Osteoclasts remained capable of lacunar resorption, even at high ECF [Ca(2+)]e, in keeping with their role in physiological and pathological bone resorption.

  19. Aortic stiffness is associated with cardiac function and cerebral small vessel disease in patients with type 1 diabetes mellitus: assessment by magnetic resonance imaging

    Energy Technology Data Exchange (ETDEWEB)

    Elderen, Saskia G.C. van; Brandts, A.; Westenberg, J.J.M.; Grond, J. van der; Buchem, M.A. van; Kroft, L.J.M.; Roos, A. de [Leiden University Medical Center, Department of Radiology, Leiden (Netherlands); Tamsma, J.T.; Romijn, J.A.; Smit, J.W.A. [Leiden University Medical Center, Department of Endocrinology, Leiden (Netherlands)

    2010-05-15

    To evaluate, with the use of magnetic resonance imaging (MRI), whether aortic pulse wave velocity (PWV) is associated with cardiac left ventricular (LV) function and mass as well as with cerebral small vessel disease in patients with type 1 diabetes mellitus (DM). We included 86 consecutive type 1 DM patients (49 male, mean age 46.9 {+-} 11.7 years) in a prospective, cross-sectional study. Exclusion criteria included aortic/heart disease and general MRI contra-indications. MRI of the aorta, heart and brain was performed for assessment of aortic PWV, as a marker of aortic stiffness, systolic LV function and mass, as well as for the presence of cerebral white matter hyperintensities (WMHs), microbleeds and lacunar infarcts. Multivariate linear or logistic regression was performed to analyse the association between aortic PWV and outcome parameters, with covariates defined as age, gender, mean arterial pressure, heart rate, BMI, smoking, DM duration and hypertension. Mean aortic PWV was 7.1 {+-} 2.5 m/s. Aortic PWV was independently associated with LV ejection fraction (ss= -0.406, P = 0.006), LV stroke volume (ss=-0.407, P = 0.001), LV cardiac output (ss= -0.458, P = 0.001), and with cerebral WMHs (P < 0.05). There were no independent associations between aortic stiffness and LV mass, cerebral microbleeds or lacunar infarcts. Aortic stiffness is independently associated with systolic LV function and cerebral WMHs in patients with type 1 DM. (orig.)

  20. An Inflammatory Polymorphisms Risk Scoring System for the Differentiation of Ischemic Stroke Subtypes

    Science.gov (United States)

    Muiño, Elena; Krupinski, Jurek; Carrera, Caty; Gallego-Fabrega, Cristina; Montaner, Joan; Fernández-Cadenas, Israel

    2015-01-01

    Inflammation has been associated with atherothrombotic stroke and recently with cardioembolic stroke. Different genetic risk factors have been specifically associated with the subtypes of ischemic stroke (cardioembolic, atherothrombotic, and lacunar). However, there are no studies that have generated genetic risk scores for the different subtypes of ischemic stroke using polymorphisms associated with inflammation. Methods. We have analyzed 68 polymorphisms of 30 inflammatory mediator genes in 2,685 subjects: 1,987 stroke cases and 698 controls. We generated a genetic scoring system with the most significant polymorphisms weighted by the odds ratio of every polymorphism and taken into consideration the stroke subtype. Results. Three polymorphisms, rs1205 (CRP gene), rs1800779, and rs2257073 (NOS3 gene), were associated with cardioembolic stroke (p value <0.05). The score generated was only associated with the cardioembolic stroke subtype (p value: 0.001) and was replicated in an independent cohort (p value: 0.017). The subjects with the highest score presented a cardioembolic stroke in 92.2% of the cases (p value: 0.002). Conclusion. The genetics of inflammatory markers is more closely associated with cardioembolic strokes than with atherothrombotic or lacunar strokes. The genetic risk scoring system could be useful in the prediction and differentiation of ischemic stroke; however, it might be specific to particular ischemic stroke subtypes. PMID:26355258

  1. Impaired executive function following ischemic stroke in the rat medial prefrontal cortex.

    Science.gov (United States)

    Cordova, Chris A; Jackson, Danielle; Langdon, Kristopher D; Hewlett, Krista A; Corbett, Dale

    2014-01-01

    Small (lacunar) infarcts frequently arise in frontal and midline thalamic regions in the absence of major stroke. Damage to these areas often leads to impairment of executive function likely as a result of interrupting connections of the prefrontal cortex. Thus, patients experience frontal-like symptoms such as impaired ability to shift ongoing behavior and attention. In contrast, executive dysfunction has not been demonstrated in rodent models of stroke, thereby limiting the development of potential therapies for human executive dysfunction. Male Sprague-Dawley rats (n=40) underwent either sham surgery or bilateral endothelin-1 injections in the mediodorsal nucleus of the thalamus or in the medial prefrontal cortex. Executive function was assessed using a rodent attention set shifting test that requires animals to shift attention to stimuli in different stimulus dimensions. Medial prefrontal cortex ischemia impaired attention shift performance between different stimulus dimensions while sparing stimulus discrimination and attention shifts within a stimulus dimension, indicating a selective attention set-shift deficit. Rats with mediodorsal thalamic lacunar damage did not exhibit a cognitive impairment relative to sham controls. The selective attention set shift impairment observed in this study is consistent with clinical data demonstrating selective executive disorders following stroke within specific sub-regions of frontal cortex. These data contribute to the development and validation of a preclinical animal model of executive dysfunction, that can be employed to identify potential therapies for ameliorating cognitive deficits following stroke.

  2. Cerebral hemodynamic dysfunction in parkinsonian patients

    Directory of Open Access Journals (Sweden)

    Mirjana Vladetić

    2009-02-01

    Full Text Available Aim The purpose of this investigation was to determine the cerebral hemodynamics in patients withparkinsonism and the influence of hemodynamic dysfunction in developing the lacunar infarcts.Methods Fifty patients with the signs of parkinsonism were included in this study. The patients weredevided into two subgroups depending on whether they had vascular parkinsonism (VP (N-22 or idiopathicParkinson disease (N-28. The control group consisted of 30 patients who had ischemic stroke.The conventional transcranial dopler sonography was performed to evaluate the cerebral blood flow.To evaluate the cognitive impairment we performed the mini mental state examination to patients withparkinsonism.Results Patients with vascular parkinsonism have greater cognitive disturbances than patients withParkinson disease. In most of the parkinsonian patients the cerebral blood flow was decreased and themicroangiopathy was present.Conclusion In most patients with parkinsonism, the cerebral blood flow was decreased as a consequenceof microangiopathy. In our opinion, this led to lacunar infarction in VP patients, but can also bea risk factor for developing the same changes in patients with idiopathic Parkinson disease.

  3. An analysis of Methylenetetrahydrofolate reductase and Glutathione S-transferase omega-1 genes as modifiers of the cerebral response to ischemia

    Directory of Open Access Journals (Sweden)

    Sen Souvik

    2009-07-01

    Full Text Available Abstract Background Cerebral ischemia involves a series of reactions which ultimately influence the final volume of a brain infarction. We hypothesize that polymorphisms in genes encoding proteins involved in these reactions could act as modifiers of the cerebral response to ischemia and impact the resultant stroke volume. The final volume of a cerebral infarct is important as it correlates with the morbidity and mortality associated with non-lacunar ischemic strokes. Methods The proteins encoded by the methylenetetrahydrofolate reductase (MTHFR and glutathione S-transferase omega-1 (GSTO-1 genes are, through oxidative mechanisms, key participants in the cerebral response to ischemia. On the basis of these biological activities, they were selected as candidate genes for further investigation. We analyzed the C677T polymorphism in the MTHFR gene and the C419A polymorphism in the GSTO-1 gene in 128 patients with non-lacunar ischemic strokes. Results We found no significant association of either the MTHFR (p = 0.72 or GSTO-1 (p = 0.58 polymorphisms with cerebral infarct volume. Conclusion Our study shows no major gene effect of either the MTHFR or GSTO-1 genes as a modifier of ischemic stroke volume. However, given the relatively small sample size, a minor gene effect is not excluded by this investigation.

  4. On the fractal distribution of primes and prime-indexed primes by the binary image analysis

    Science.gov (United States)

    Cattani, Carlo; Ciancio, Armando

    2016-10-01

    In this paper, the distribution of primes and prime-indexed primes (PIPs) is studied by mapping primes into a binary image which visualizes the distribution of primes. These images show that the distribution of primes (and PIPs) is similar to a Cantor dust, moreover the self-similarity with respect to the order of PIPs (already proven in Batchko (2014)) can be seen as an invariance of the binary images. The index of primes plays the same role of the scale for fractals, so that with respect to the index the distribution of prime-indexed primes is characterized by the self-similarity alike any other fractal. In particular, in order to single out the scale dependence, the PIPs fractal distribution will be evaluated by limiting to two parameters, fractal dimension (δ) and lacunarity (λ), that are usually used to measure the fractal nature. Because of the invariance of the corresponding binary plots, the fractal dimension and lacunarity of primes distribution are invariant with respect to the index of PIPs.

  5. Oscillatory Positive Expiratory Pressure in Chronic Obstructive Pulmonary Disease.

    Science.gov (United States)

    Svenningsen, Sarah; Paulin, Gregory A; Sheikh, Khadija; Guo, Fumin; Hasany, Aasim; Kirby, Miranda; Rezai, Roya Etemad; McCormack, David G; Parraga, Grace

    2016-01-01

    Evidence-based guidance for the use of airway clearance techniques (ACT) in chronic obstructive pulmonary disease (COPD) is lacking in-part because well-established measurements of pulmonary function such as the forced expiratory volume in 1s (FEV1) are relatively insensitive to ACT. The objective of this crossover study was to evaluate daily use of an oscillatory positive expiratory pressure (oPEP) device for 21-28 days in COPD patients who were self-identified as sputum-producers or non-sputum-producers. COPD volunteers provided written informed consent to daily oPEP use in a randomized crossover fashion. Participants completed baseline, crossover and study-end pulmonary function tests, St. George's Respiratory Questionnaire (SGRQ), Patient Evaluation Questionnaire (PEQ), Six-Minute Walk Test and (3)He magnetic resonance imaging (MRI) for the measurement of ventilation abnormalities using the ventilation defect percent (VDP). Fourteen COPD patients, self-identified as sputum-producers and 13 COPD-non-sputum-producers completed the study. Post-oPEP, the PEQ-ease-bringing-up-sputum was improved for sputum-producers (p = 0.005) and non-sputum-producers (p = 0.04), the magnitude of which was greater for sputum-producers (p = 0.03). There were significant post-oPEP improvements for sputum-producers only for FVC (p = 0.01), 6MWD (p = 0.04), SGRQ total score (p = 0.01) as well as PEQ-patient-global-assessment (p = 0.02). Clinically relevant post-oPEP improvements for PEQ-ease-bringing-up-sputum/PEQ-patient-global-assessment/SGRQ/VDP were observed in 8/7/9/6 of 14 sputum-producers and 2/0/3/3 of 13 non-sputum-producers. The post-oPEP change in (3)He MRI VDP was related to the change in PEQ-ease-bringing-up-sputum (r = 0.65, p = 0.0004) and FEV1 (r = -0.50, p = 0.009). In COPD patients with chronic sputum production, PEQ and SGRQ scores, FVC and 6MWD improved post-oPEP. FEV1 and PEQ-ease-bringing-up-sputum improvements were related to improved ventilation providing

  6. Fostering Effective Studying and Study Planning with Study Questions

    Science.gov (United States)

    Wilhelm, Pascal; Pieters, Jules M.

    2007-01-01

    In a course on biological psychology and neuropsychology, study questions were provided that also appeared as test questions in the course exam. This method was introduced to support students in active processing and reproduction of the study texts, and study planning. Data were gathered to test the hypothesis that study question use would be…

  7. Case Study: Testing with Case Studies

    Science.gov (United States)

    Herreid, Clyde Freeman

    2015-01-01

    This column provides original articles on innovations in case study teaching, assessment of the method, as well as case studies with teaching notes. This month's issue discusses using case studies to test for knowledge or lessons learned.

  8. Principal component analysis of the CT density histogram to generate parametric response maps of COPD

    Science.gov (United States)

    Zha, N.; Capaldi, D. P. I.; Pike, D.; McCormack, D. G.; Cunningham, I. A.; Parraga, G.

    2015-03-01

    Pulmonary x-ray computed tomography (CT) may be used to characterize emphysema and airways disease in patients with chronic obstructive pulmonary disease (COPD). One analysis approach - parametric response mapping (PMR) utilizes registered inspiratory and expiratory CT image volumes and CT-density-histogram thresholds, but there is no consensus regarding the threshold values used, or their clinical meaning. Principal-component-analysis (PCA) of the CT density histogram can be exploited to quantify emphysema using data-driven CT-density-histogram thresholds. Thus, the objective of this proof-of-concept demonstration was to develop a PRM approach using PCA-derived thresholds in COPD patients and ex-smokers without airflow limitation. Methods: Fifteen COPD ex-smokers and 5 normal ex-smokers were evaluated. Thoracic CT images were also acquired at full inspiration and full expiration and these images were non-rigidly co-registered. PCA was performed for the CT density histograms, from which the components with the highest eigenvalues greater than one were summed. Since the values of the principal component curve correlate directly with the variability in the sample, the maximum and minimum points on the curve were used as threshold values for the PCA-adjusted PRM technique. Results: A significant correlation was determined between conventional and PCA-adjusted PRM with 3He MRI apparent diffusion coefficient (p<0.001), with CT RA950 (p<0.0001), as well as with 3He MRI ventilation defect percent, a measurement of both small airways disease (p=0.049 and p=0.06, respectively) and emphysema (p=0.02). Conclusions: PRM generated using PCA thresholds of the CT density histogram showed significant correlations with CT and 3He MRI measurements of emphysema, but not airways disease.

  9. Paraguayan Education Study: A Pilot Study.

    Science.gov (United States)

    Garcia, Patricia

    A qualitative pilot study, guided by an ecological framework, illustrates the complexities involved in studying the unique linguistic situation in Paraguay between Spanish and the indigenous language of Guarani, and its relationship with education. The pilot study interviewing eight kindergarten children. Seventy five children have been…

  10. Case Study: Writing a Journal Case Study

    Science.gov (United States)

    Prud'homme-Genereux, Annie

    2016-01-01

    This column provides original articles on innovations in case study teaching, assessment of the method, as well as case studies with teaching notes. This month's issue describes incorporating a journal article into the classroom by first converting it into a case study.

  11. Feasibibility study - cases

    DEFF Research Database (Denmark)

    Lund, Henrik; Hvelplund, Frede Kloster; Sukkumnoed, Decharut

    2004-01-01

    The chapter presents two case studies to show the tools of feasibiliy studies within the context of technological innovation.......The chapter presents two case studies to show the tools of feasibiliy studies within the context of technological innovation....

  12. Building Transdisciplinary Environmental Studies

    DEFF Research Database (Denmark)

    Holm, Jesper

    2006-01-01

    Conceptual analytical-methodological conceptualization of crossdisciplinary sustainability studies......Conceptual analytical-methodological conceptualization of crossdisciplinary sustainability studies...

  13. German Studies in America. German Studies Notes.

    Science.gov (United States)

    Sander, Volkmar; Osterle, Heinz D.

    This volume contains two papers, "German Studies in America," by Volkmar Sander, and "Historicism, Marxism, Structuralism: Ideas for German Culture Courses," by Heinz D. Osterle. The first paper discusses the position of German studies in the United States today. The greatest challenge comes from low enrollments; therefore,…

  14. Study of lip prints: A forensic study

    Directory of Open Access Journals (Sweden)

    Vikash Ranjan

    2014-01-01

    Full Text Available Background: Although several studies have been done on lip prints for human identification in forensic science, there is a doubt about their use in gender determination. Aims: The present study was designed to study the lip groove patterns in all the quadrants of both male and female subjects to identify the sex, based on the patterns of the grooves of the lip prints. Study Design: 300 lip prints were collected from volunteers of D. J. College of Dental Sciences and Research, Modinagar (UP. Materials and Methods: Lip prints were recorded with lip stick and transferred on to a glass slide. Statistical Analysis: Pearson chi-square test was adopted for statistical analysis and probability value (P value was calculated. Conclusion: In our study, none of the lip prints were identical, thus confirming the role of lip prints in individual identification. According to Suzuki′s classification, Type I, II, III and IV patterns were significant in gender determination.

  15. Cerebrovascular risk factors and clinical classification of strokes.

    Science.gov (United States)

    Pinto, Antonio; Tuttolomondo, Antonino; Di Raimondo, Domenico; Fernandez, Paola; Licata, Giuseppe

    2004-08-01

    Cerebrovascular risk represents a progressive and evolving concept owing to the particular distribution of risk factors in patients with ischemic stroke and in light of the newest stroke subtype classifications that account for pathophysiological, instrumental, and clinical criteria. Age represents the strongest nonmodifiable risk factor associated with ischemic stroke, while hypertension constitutes the most important modifiable cerebrovascular risk factor, confirmed by a host of epidemiological data and by more recent intervention trials of primary (HOT, Syst-Eur, LIFE) and secondary (PROGRESS) prevention of stroke in hypertensive patients. To be sure, a curious relationship exists between stroke and diabetes. Although the Framingham Study, The Honolulu Heart Program, and a series of Finnish studies reported a linear relationship between improved glucose metabolism and cerebral ischemia, the clinical and prognostic profile of diabetic patients with ischemic stroke remains to be fully understood. Our group, on the basis of TOAST classification--a diagnostic classification of ischemic stroke developed in 1993 that distinguishes five different clinical subtypes of ischemic stroke: large-artery atherosclerosis (LAAS), cardioembolic infarct (CEI), lacunar infarct (LAC), stroke of other determined origin (ODE), and stroke of undetermined origin (UDE), and now extensively used in clinical and scientific context--analysed the prevalence of cerebrovascular risk factors and the distribution of TOAST subtypes in more 300 patients with acute ischemic stroke in two consecutives studies that reported the significant association between diabetes and the lacunar subtype and a better clinical outcome for diabetic patients, most likely related to the higher prevalence of the lacunar subtype. Well-confirmed are the roles of cigarette smoking, atrial fibrillation, and asymptomatic carotid stenosis as cerebrovascular risk factors. Particularly interesting seems to be the function of

  16. Mechanisms of osteocyte stimulation in osteoporosis.

    Science.gov (United States)

    Verbruggen, Stefaan W; Vaughan, Ted J; McNamara, Laoise M

    2016-09-01

    Experimental studies have shown that primary osteoporosis caused by oestrogen-deficiency results in localised alterations in bone tissue properties and mineral composition. Additionally, changes to the lacunar-canalicular architecture surrounding the mechanosensitive osteocyte have been observed in animal models of the disease. Recently, it has also been demonstrated that the mechanical stimulation sensed by osteocytes changes significantly during osteoporosis. Specifically, it was shown that osteoporotic bone cells experience higher maximum strains than healthy bone cells after short durations of oestrogen deficiency. However, in long-term oestrogen deficiency there was no significant difference between bone cells in healthy and normal bone. The mechanisms by which these changes arise are unknown. In this study, we test the hypothesis that complex changes in tissue composition and lacunar-canalicular architecture during osteoporosis alter the mechanical stimulation of the osteocyte. The objective of this research is to employ computational methods to investigate the relationship between changes in bone tissue composition and microstructure and the mechanical stimulation of osteocytes during osteoporosis. By simulating physiological loading, it was observed that an initial decrease in tissue stiffness (of 0.425GPa) and mineral content (of 0.66wt% Ca) relative to controls could explain the mechanical stimulation observed at the early stages of oestrogen deficiency (5 weeks post-OVX) during in situ bone cell loading in an oestrogen-deficient rat model of post-menopausal osteoporosis (Verbruggen et al., 2015). Moreover, it was found that a later increase in stiffness (of 1.175GPa) and mineral content (of 1.64wt% Ca) during long-term osteoporosis (34 weeks post-OVX), could explain the mechanical stimuli previously observed at a later time point due to the progression of osteoporosis. Furthermore, changes in canalicular tortuosity arising during osteoporosis were shown

  17. Humanities, Digital Humanities, Media studies, Internet studies

    DEFF Research Database (Denmark)

    Brügger, Niels

    the interplay between four areas which until now to a certain extent have been separated: Traditional Hu- manities, Digital Humanities, Media studies, and Internet studies. The vision is followed by an outline of how it can be unfolded in concrete activities, in the form of research projects, research......Todays expanding digital landscape constitutes an important research object as well as the research environment for the Humanities at the beginning of the 21st century. Taking this state of affairs as a starting point this inaugural lecture presents a vision for how the digital affects...

  18. [Epidemiology of stroke in Japan and comparison with the world].

    Science.gov (United States)

    Furuta, Yoshihiko; Ninomiya, Toshiharu

    2016-04-01

    Stroke was the leading cause of death in Japan until 1980s. The results from the Hisayama study, which is a population-based study in Japan, showed that incidence and mortality of stroke decreased with time owing to the improved management of hypertension. Although the incidence of hemorrhagic stroke decreased markedly, the proportion of hemorrhagic stroke among the incident cases of stroke in Japan is higher than in European countries. Among the incident cases of ischemic stroke, the proportion of lacunar infarction decreased significantly, whereas the proportion of atherothrombotic and cardioembolic stroke increased. These changes may be caused by elevating prevalence of metabolic disorders-namely, diabetes and hypercholesterolemia. Effective prevention and management of the metabolic disorder are necessary for further prevention of stroke.

  19. Case study research.

    Science.gov (United States)

    Taylor, Ruth; Thomas-Gregory, Annette

    2015-06-10

    This article describes case study research for nursing and healthcare practice. Case study research offers the researcher an approach by which a phenomenon can be investigated from multiple perspectives within a bounded context, allowing the researcher to provide a 'thick' description of the phenomenon. Although case study research is a flexible approach for the investigation of complex nursing and healthcare issues, it has methodological challenges, often associated with the multiple methods used in individual studies. These are explored through examples of case study research carried out in practice and education settings. An overview of what constitutes 'good' case study research is proposed.

  20. FEMA DFIRM Study Info

    Data.gov (United States)

    Minnesota Department of Natural Resources — This table contains details about the study such as the study name, datum, projection, etc. There is normally only one record in this table for each Flood Insurance...

  1. 522 Postmarket Surveillance Studies

    Data.gov (United States)

    U.S. Department of Health & Human Services — The 522 Postmarket Surveillance Studies Program encompasses design, tracking, oversight, and review responsibilities for studies mandated under section 522 of the...

  2. Future Circular Collider Study

    CERN Document Server

    Benedikt, Michael

    2014-01-01

    This presentation has been given during the 1st EuCARD-2 annual meeting. It contains: • Motivation & scope • Parameters & design challenges • Study organization, study time line • Preparing global FCC collaboration • Summary

  3. Case Study Teaching

    Science.gov (United States)

    Herreid, Clyde Freeman

    2011-01-01

    This chapter describes the history of case study teaching, types of cases, and experimental data supporting their effectiveness. It also describes a model for comparing the efficacy of the various case study methods. (Contains 1 figure.)

  4. Post-Approval Studies

    Data.gov (United States)

    U.S. Department of Health & Human Services — The CDRH Post-Approval Studies Program encompasses design, tracking, oversight, and review responsibilities for studies mandated as a condition of approval of a...

  5. Chemical Industry Bandwidth Study

    Energy Technology Data Exchange (ETDEWEB)

    none,

    2006-12-01

    The Chemical Bandwidth Study provides a snapshot of potentially recoverable energy losses during chemical manufacturing. The advantage of this study is the use of "exergy" analysis as a tool for pinpointing inefficiencies.

  6. What Are Sleep Studies?

    Science.gov (United States)

    ... Share this page from the NHLBI on Twitter. Sleep Studies Also known as polysomnography. Sleep studies are ... Sleep Rate This Content: Updated: December 9, 2016 Sleep Infographic Sleep Disorders & Insufficient Sleep: Improving Health through ...

  7. CISSP study guide

    CERN Document Server

    Conrad, Eric; Feldman, Joshua; Riggins, Kevin

    2011-01-01

    "The Eleventh Hour CISSP Study Guide" is keyed to the latest CISSP exam. This book is streamlined to include only core certification information and is presented for ease of last-minute studying. Main objectives of the exam are covered concisely with key concepts highlighted. This is the only guide you need for last-minute studying. This title answers the toughest questions and highlights core topics. This title can be paired with any other study guide so you are completely prepared.

  8. Pyridostigmine Synergistic Toxicity Study.

    Science.gov (United States)

    1995-05-31

    AND DEET IN THE LABORATORY RAT 1. Executive Sum m ary .............................................................................................. 2 2...TOXICOLOGICAL STUDY 75-48-2665 ACUTE ORAL TOXICITY STUDY OF PYRIDOSTIGMINE BROMIDE. PERMETHRIN. AND DEET IN THE LABORATORY RAT 1. REFERENCES: See Appendix A... LABORATORY RAT 1. PURPOSE: The purpose of this study was to determine potential toxic interactions when pyridostigmine bromide. permethrin. and DEET are given

  9. Social Psychoanalytic Disability Studies

    Science.gov (United States)

    Goodley, Dan

    2011-01-01

    This paper explores connections and tensions between psychoanalysis and disability studies. The first part of the paper considers contemporaneous engagements with the psyche by a number of disability studies writers. These scholars have remained accountable to a politicised disability studies but have pushed for critical encounters with the…

  10. STUDYING ON THE INTERNET

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    正Nowadays the Internet is more and more popular.I think it is a good way of learning. First,the Intemet enables people to study whenever and wherever it is convenient. They can also choose to study whatever they are interested in.However,a traditional school doesn't provide such great freedom.Students have to study given sub-

  11. Cross-cultural studies using a modified mini mental test for healthy subjects and patients with various forms of vascular dementia.

    Science.gov (United States)

    Thajeb, Peterus; Thajeb, Teguh; Dai, Daofu

    2007-03-01

    Existing neuropsychological tests are often complex and time-consuming. We designed a modified Mini Mental Test (MMT) battery for clinical assessment of the global and regional higher cortical functions of the brain. We tested its applicability in healthy subjects with different ethnic, cultural and educational backgrounds. The usefulness of our MMT as a tool for the clinical evaluation of patients with various forms of vascular dementia was determined. The MMT comprises five subtests, including clinical evaluations of: (A) orientation (6 points); (B) attention, right-left discrimination, speech, and calculation (20); (C) immediate recall, and recent and remote memory retrieval (10); (D) praxis (10); and (E) visuospatial orientation, agnosia, hemianopsia, and visual hemineglect (14). The MMT was administered to 100 healthy subjects from two different ethnic backgrounds (Indonesian and Chinese/Taiwanese) and diverse cultural and educational backgrounds, and to 61 patients with various forms of vascular dementia. MMT scores were significantly lower in healthy subjects with a low level of education regardless of their ethnic background (p<0.001). Patients with vascular dementia had much lower MMT scores than did the comparable age-adjusted normal controls (p<0.001). Of the patients with vascular dementia, those with Binswanger's disease had the lowest MMT scores (25.5+/-28.9), followed by those with large cerebral infarcts (48.0+/-7.1), cerebral haemorrhage (49.0+/-8.5), and multiple lacunar infarctions (55.0+/-0.5) (P<0.001). With a cut-off point of 33/55 (partial score/total score), the sensitivity and positive predictive value of the MMT were 0.98 and 0.94, respectively. The MMT is a simple and useful tool for clinical assessment of the cognitive functions of healthy subjects and patients with or without vascular dementia. It can be used for individuals with different ethnic, cultural and educational backgrounds.

  12. Study deep geothermal energy; Studie dypgeotermisk energi

    Energy Technology Data Exchange (ETDEWEB)

    Havellen, Vidar; Eri, Lars Sigurd; Andersen, Andreas; Tuttle, Kevin J.; Ruden, Dorottya Bartucz; Ruden, Fridtjof; Rigler, Balazs; Pascal, Christophe; Larsen, Bjoern Tore

    2012-07-01

    The study aims to analyze the potential energy with current technology, challenges, issues and opportunities for deep geothermal energy using quantitative analysis. It should especially be made to identify and investigate critical connections between geothermal potential, the size of the heating requirements and technical solutions. Examples of critical relationships may be acceptable cost of technology in relation to heating, local geothermal gradient / drilling depth / temperature levels and profitability. (eb)

  13. Studying Engineering Practice

    DEFF Research Database (Denmark)

    Buch, Anders

    2015-01-01

    The study of engineering practices has been the focus of Engineering Studies over the last three decades. Theses studies have used ethnographic and grounded methods in order to investigate engineering practices as they unfold in natural settings - in workplaces and engineering education. However......, engineering studies have not given much attention to conceptually clarifying what should be understood by 'engineering practices' and more precisely account for the composition and organization of the entities and phenomena that make up the practices. This chapter investigates and discusses how a 'practice...... will draw out some methodological consequences and discuss the ramifications of a practice theoretical approach for Engineering Studies....

  14. High-flow priapism treated with superselective transcatheter embolization using polyvinyl alcohol particles

    Science.gov (United States)

    Sánchez-López, Sebastián; González-Gómez, Silvia; Di lizio-Miele, Katyna; González-Gómez, Joaquín

    2017-01-01

    Objectives: Priapism is a persistent erection of the penis not associated with sexual stimulation. High-flow priapism is caused by unregulated arterial inflow, usually preceded by perineal or penile blunt trauma and formation of an arterial-lacunar fistula. We present a case of high-flow priapism in a 13-year-old patient managed with polyvinyl alcohol particles. Methods: After obtaining informed consent of the parents of the minor, diagnosis was made with penile Color Doppler Ultrasound and confirmed with flush angiography. Selective arterial embolization was performed with the use of polyvinyl alcohol particles. Results: Complete detumescence was achieved without compromising the patient’s erectile function. Conclusions: The use of permanent occlusive agents like polyvinyl alcohol particles for embolization shows good occlusion rates compared to temporary agents. More studies are needed to find the safer and better agent for the treatment of high flow priapism without compromising erectile function. PMID:28255447

  15. A diffusion-based approach to obtaining the borders of urban areas

    Science.gov (United States)

    Henrique Comin, Cesar; Nascimento Silva, Filipi; da Fontoura Costa, Luciano

    2016-05-01

    The access to an ever increasing amount of information in the modern world gave rise to the development of many quantitative indicators about urban regions in the globe. Therefore, there is a growing need for a precise definition of how to delimit urban regions, so as to allow proper respective characterization and modeling. Here we present a straightforward methodology to automatically detect urban region borders around a single seed point. The method is based on a diffusion process having street crossings and terminations as source points. We exemplify the potential of the methodology by characterizing the geometry and topology of 21 urban regions obtained from 8 distinct countries. The geometry is studied by employing the lacunarity measurement, which is associated to the regularity of holes contained in a pattern. The topology is analyzed by associating the betweenness centrality of the streets with their respective class, such as motorway or residential, obtained from a database.

  16. Electronic teaching materials for inter-professional education in a college of medical professionals.

    Science.gov (United States)

    Toyama, Hinako; Inoue, Rie; Ito, Yumi; Sakamoto, Chieko; Ishikawa, Toru; Eda, Tetsuya; Saito, Keiichi

    2013-01-01

    In order to promote the utilization of digital clinical information among medical professionals, an education program and electronic teaching materials involving fictitious model patients were developed for students in a health and welfare college. The purposes of this program were for students to learn the role of each medical professional and to understand the medical records written by each medical staff member in interdisciplinary medicine (a collaborative approach to medicine). The materials for fictitious patients, including medical records, study results, medical images and the associated documents, were stored in a database on a virtual private network. The electronic medical records were easily modified according to the specialty of the students in each class. Fictional medical records of patients with lacunar infarction, fracture of the distal radius, fracture of the femur, diabetes mellitus and breast cancer were generated and evaluated in inter-professional education classes.

  17. Intelligence impairment, personality features and psychopathology disturbances in a family affected with CADASIL.

    Science.gov (United States)

    Domínguez-Sánchez, Francisco Javier; Lasa-Aristu, Amaia; Goñi-Imízcoz, Miguel

    2011-11-01

    Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is a small-vessel disease of the brain that is characterized by headache, recurring lacunar strokes, mood changes and progressive cognitive deterioration. The disease is transmitted with an autosomal dominant pattern and usually starts during midadulthood (at 30-50 years of age). Cognitive deficits in patients with CADASIL develop slowly. The dementia causes frontal-like symptoms and it typically develops after a history of recurrent stroke. We describe three patients from one Spanish family affected by this disease. All three cases underwent comprehensive clinical and neuropsychological examination, and were monitored for seven years. The results obtained in this study describe a) a significant loss of the intelligence quotient (IQ) and noticeable damage to abstract ability (g factor), b) mood and psychopathological disturbances (major depression and dysthymia), and c) a personality with neurotic features.

  18. Thermal properties of composite materials: a complex systems approximation

    Science.gov (United States)

    Carrillo, J. L.; Bonilla, Beatriz; Reyes, J. J.; Dossetti, Victor

    We propose an effective media approximation to describe the thermal diffusivity of composite samples made of polyester resin and magnetite inclusions. By means of photoacoustic spectroscopy, the thermal diffusivity of the samples were experimentally measured. The volume fraction of the inclusions was systematically varied in order to study the changes in the effective thermal diffusivity of the composites. For some samples, a static magnetic field was applied during the polymerization process, resulting in anisotropic inclusion distributions. Our results show a significant difference in the thermal properties of the anisotropic samples, compared to the isotropic randomly distributed. We correlate some measures of the complexity of the inclusion structure with the observed thermal response through a multifractal analysis. In this way, we are able to describe, and at some extent predict, the behavior of the thermal diffusivity in terms of the lacunarity and other measures of the complexity of these samples Partial Financial Support by CONACyT México and VIEP-BUAP.

  19. Obtaining the borders of urban areas

    CERN Document Server

    Comin, Cesar Henrique; Costa, Luciano da Fontoura

    2015-01-01

    The access to an ever increasing amount of information in the modern world gave rise to the development of many quantitative indicators about urban regions in the globe. Therefore, there is a growing need for a precise definition of how to delimit urban regions, so as to allow proper respective characterization and modeling. Here we present a straightforward methodology to automatically detect urban region borders. The method is based on the density of street crossings around a single seed point associated to the urban area of interest. We exemplify the potential of the methodology by characterizing the geometry and topology of 21 urban regions obtained from 8 distinct countries. The geometry is studied by employing the lacunarity measurement, which is associated to the regularity of holes contained in a pattern. The topology is analyzed by associating the betweenness centrality of the streets with their respective class, such as motorway or residential, obtained from a database.

  20. Pathophysiology of brain ischemia as it relates to the therapy of acute ischemic stroke

    DEFF Research Database (Denmark)

    Lassen, N A

    1990-01-01

    Current knowledge of the pathophysiology of cerebral ischemia, summarized in the present study, predicts that neurological deficits caused by moderate ischemia (flows in the penumbral range between 23 and 10 ml/100 g/min) are reversible provided flow is restored within 3-4 h of onset. It also...... predicts that areas of dense ischemia cannot be salvaged and that reperfusion of such areas is risky, because massive edema or even hemorrhage may develop following reperfusion. On this basis, it is argued that selection of stroke cases for thrombolysis or surgical revascularization must be based not only...... on computed tomographic (CT) scanning to exclude hemorrhagic stroke, but also on cerebral blood flow (CBF) tomography to exclude lacunar infarcts, early reperfusion, and dense ischemia. The methods available for routing CBF tomography in acute stroke cases are discussed, and it is concluded that single photon...

  1. Lacunary Fourier Series for Compact Quantum Groups

    Science.gov (United States)

    Wang, Simeng

    2016-05-01

    This paper is devoted to the study of Sidon sets, {Λ(p)} -sets and some related notions for compact quantum groups. We establish several different characterizations of Sidon sets, and in particular prove that any Sidon set in a discrete group is a strong Sidon set in the sense of Picardello. We give several relations between Sidon sets, {Λ(p)} -sets and lacunarities for L p -Fourier multipliers, generalizing a previous work by Blendek and Michalic̆ek. We also prove the existence of {Λ(p)} -sets for orthogonal systems in noncommutative L p -spaces, and deduce the corresponding properties for compact quantum groups. Central Sidon sets are also discussed, and it turns out that the compact quantum groups with the same fusion rules and the same dimension functions have identical central Sidon sets. Several examples are also included.

  2. Lipid Transport through the Fetoplacental Barrier by the Fatty Acid-Binding Proteins in Pregnant Women with Herpes Virus Infection in the third Trimester

    Directory of Open Access Journals (Sweden)

    Michael T. Lucenko, PhD, ScD

    2012-12-01

    Full Text Available In this study, the transport of the long chain polyunsaturated fatty acids (LCPUFAs from the lacunar blood through the syncytiotrophoblast of the placental villi to the fetal cord blood via a saturable protein-mediated mechanism by the heart-type fatty acid-binding proteins (H-FABPs has been examined. Exacerbation of the herpes simplex viruses (HSV-1 in the third trimester of gestation reduces the delivery of the fatty acid-binding proteins to the syncytiotrophoblast. During exacerbation of the HSV-1 infection, the selective transfer of the LCPUFAs across the syncytiotrophoblast basal plasma membrane into the fetal cord blood was observed. The supply of anti-inflammatory ω-3 PUFAs was reduced; however, the inflow of inflammatory arachidonic acid and other ω-6 PUFAs into the fetal blood was increased.

  3. Dysphagia in acute stroke: Correlation with stroke subtype, vascular territory and in-hospital respiratory morbidity and mortality

    Directory of Open Access Journals (Sweden)

    Sundar Uma

    2008-01-01

    Full Text Available Aims: The study aimed at correlation of post-stroke dysphagia with area and volume of infarct/ bleed, and with subsequent in-hospital respiratory morbidity and mortality. Materials and Methods: 50 patients of acute stroke were serially recruited. Standard Staff swallowing assessment was performed within 24 hours of admission along with pulse oximetry. Ischemic strokes were classified as per OCPS registry. In-hospital respiratory morbidity and mortality, mode of nutrition and disability status at discharge were noted. Results: 21/50 (42% patients had post-stroke dysphagia during their hospital course. Among infarcts, Total Anterior Circulation Infarcts (TACI had 100% incidence of dysphagia, followed by Partial Anterior Circulation Infarcts (PACI-36%, Posterior Circulation infarcts (POCI-33%, and Lacunar infarcts (LACI-18%. 67% of hemorrhages had post-stroke dysphagia. Staff swallowing assessment had a sensitivity and specificity of 75% and 73% respy., for predicting respiratory morbidity. The corresponding figures for Pulse oximetry were 79% and 91%.

  4. Cerebral infarction following intracranial hemorrhage in pediatric Moyamoya disease - A case report and brief review of literature

    Directory of Open Access Journals (Sweden)

    Soumya Patra

    2012-01-01

    Full Text Available Moyamoya disease is a clinical entity characterized by progressive cerebrovascular occlusion with spontaneous development of a collateral vascular network called Moyamoya vessels. This disease mainly manifests as cerebral ischemia. Intracranial bleeding is another major presentation of patients with Moyamoya disease. We report here a 12-year-old male child who presented with severe headache, vomiting and meningismus. Initial neuroimaging study with noncontrast computed tomography scan revealed fresh intraventricular hemorrhage in right-sided lateral ventricle. Magnetic resonance imaging with angiography of brain was done 5 days later when the child developed right-sided hemiparesis, and the diagnosis of Moyamoya disease was confirmed along with lacunar infarction of right posterior peri and paraventricular area and in the left paraventricular area and centrum semiovale. Simultaneous presence of cerebral infarction along with intraventricular hemorrhage in adult with bleeding-type Moyamoya disease is reported in literature, but it is a rare entity in a child.

  5. The study of early recurrence factors of cerebral watershed infarction%分水岭脑梗死患者复发的危险因素分析

    Institute of Scientific and Technical Information of China (English)

    殷萍; 魏亚芬

    2013-01-01

    目的 分析分水岭脑梗死(WSI)的临床特点,探讨引起WSI早期复发的危险因素.方法 选取2010年1月至2012年12月黑龙江省医院神经内科收治的前循环脑梗死患者283例,收集所有患者年龄、性别、卒中危险因素及血管狭窄程度,283例患者包括腔隙性脑梗死组83例、大面积脑梗死组60例、WSI组140例.随访半年,观察各组患者复发情况.收集WSI患者复发前后美国国立卫生研究院卒中量表(NIHSS)评分并进行比较.比较复发与未复发组WSI患者各项卒中危险因素有无差异.结果 (1) WSI组、大面积脑梗死组、腔隙性脑梗死组患者半年复发率分别为40.0%(56/140)、30.0%(18/60)、9.6%(8/83),复发率与腔隙性脑梗死组比较差异均有统计学意义(x2=23.5、x2=9.7,P均<0.01),以WSI组复发率最高.(2)WSI患者初次卒中后临床症状相对较轻,NIHSS评分0~4分者为75.7%(106/140),5~9分为22.9% (32/140),≥10分患者仅为1.4%(2/140).复发WSI患者临床症状较前明显加重,其中NIHSS评分≥10分患者比例为28.6%(16/56).(3)WSI患者复发组与未复发组各危险因素比较,不稳定斑块、基线收缩压、狭窄程度≥70%方面差异有统计学意义(P均<0.05).结论 WSI较其他类型脑梗死更易复发.WSI首次发病一般症状较轻,但复发后临床症状重、预后差.不稳定斑块、基线收缩压、狭窄程度≥70%是脑梗死复发的独立危险因素.%Objective To investigate clinical features and the early recurrence factors of watershed infarction(WSI).Methods Two hundred and eighty-three patients with acute anterior circulation vascular infraction confirmed by CT or MRI were collected in Heilongjiang Province Hospital from January 2010 to December 2012.Patients' information including gender,sex,risk factors for stroke and vascular stenosis was colleced.Patients were divided into the lacunar infarction group (n =83),large infarction group(n =60) and the WSI

  6. Translation Studies: an overview

    Directory of Open Access Journals (Sweden)

    Cristina García de Toro

    2008-04-01

    Full Text Available The article briefly outlines the main schools and approaches that make up the current landscape of Translation Studies. The purpose of this paper is to offer an introduction to translation theory for those who are beginning their studies in this field or whose knowledge of Translation Studies is tangential. The article starts with a few preliminary matters, such as the question of what Translation Studies is and how the discipline has been mapped out. Then it moves on to examine the theoretical considerations that have been developed since the second half of the 20th century, with special attention being paid to the most recent decades. In this section, which is devoted to theoretical considerations, I will review some of the fundamental issues from a theories of equivalence and comparisons between languages; b functionalist theories; c discursive approaches; d polysystem theory, descriptive studies and norms; e cultural studies; f philosophical theories; g latest contributions to the field of Translation Studies; and h interdisciplinary and integrating approaches. Keywords: translation studies, contemporary theories, linguistic approaches, descriptive studies, cultural studies.

  7. Why Study in Australia?

    Institute of Scientific and Technical Information of China (English)

    丁丽丽

    2014-01-01

    Going overseas to pursue further studies is even more generalized in recent years. Students are open to a variety of op-tions to decide which country to go and which university to choose. Why wouldn’t you want to study with some of the best minds in the world? Australia is a leading global education power, with world’s best educators and facilities. It also provides both local and international students with a variety of quality study options. This essay presents some of the important reasons why in-ternational students should study in Australia in regard to education quality, affordable fees, government support, multiple cultures and immigration policies.

  8. Contemporary American Chinese Studies

    Institute of Scientific and Technical Information of China (English)

    Qiu Huafei

    2008-01-01

    The rise of modern American scholarship on China was largely attributed to the establishment of the American Joint Committee on Contemporary China (JCCC) in 1959 which sponsored all kinds of activities to promote Chinese studies, ranging from institutional support and financial resources to training courses. Since then, American study of China has entered into a period of sustainability that features academic and group-oriented research. It has become a mainstream discipline in American social science studies.1 There are some distinctive differences between early sinology and modern Chinese Studies: the latter is much more concentrated on the study of issues, comparative historical studies, and contemporary Chinese society. American Chinese studies stresses empirical research, textual data, and the application of theory to practice.Shanghai. He was a Fulbright visiting professor at State University of New York at Geneseo from 2006-2007. This treatise is one of a series of studies for China's National Research Foundation of Philosophy and Social Science (05BGJ012), "American Chinese Studies."

  9. Studies on seismic waves

    Institute of Scientific and Technical Information of China (English)

    张海明; 陈晓非

    2003-01-01

    The development of seismic wave study in China in the past four years is reviewed. The discussion is divided into several aspects, including seismic wave propagation in laterally homogeneous media, laterally heterogeneous media, anisotropic and porous media, surface wave and seismic wave inversion, and seismic wave study in prospecting and logging problems. Important projects in the current studies on seismic wave is suggested as the development of high efficient numerical methods, and applying them to the studies of excitation and propagation of seismic waves in complex media and strong ground motion, which will form a foundation for refined earthquake hazard analysis and prediction.

  10. Information society studies

    CERN Document Server

    Duff, Alistair S

    2013-01-01

    We are often told that we are ""living in an information society"" or that we are ""information workers."" But what exactly do these claims mean, and how might they be verified? In this important methodological study, Alistair S. Duff cuts through the rhetoric to get to the bottom of the ""information society thesis."" Wide-ranging in coverage, this study will be of interest to scholars in information science, communication and media studies and social theory. It is a key text for the newly-unified specialism of information society studies, and an indispensable guide to the future of this disc

  11. Project management case studies

    CERN Document Server

    Kerzner, Harold R

    2013-01-01

    A new edition of the most popular book of project management case studies, expanded to include more than 100 cases plus a ""super case"" on the Iridium Project Case studies are an important part of project management education and training. This Fourth Edition of Harold Kerzner''s Project Management Case Studies features a number of new cases covering value measurement in project management. Also included is the well-received ""super case,"" which covers all aspects of project management and may be used as a capstone for a course. This new edition:Contains 100-plus case studies drawn from re

  12. Safety Study in Aviation

    Directory of Open Access Journals (Sweden)

    Marek Štumper

    2016-07-01

    Full Text Available The objective of this article is to provide a brief look at safety studies, which are a necessary part of every change of system or a new system in aviation. The main focus is put on the area of air traffic management, because it affects most of the aviation stakeholders. The article begins with a description of safety and safety assessment of changes in systems. Then it discusses analysis of processes, hazard identification and risk assessment. Main part focuses on Safety studies and briefly describes the elements of the study. At the end, possible ways of safety study evaluation are mentioned.

  13. Designing satisfaction studies

    DEFF Research Database (Denmark)

    Kristensen, Kai; Eskildsen, Jacob Kjær

    2007-01-01

    In the effect sampling method, presentation of researcher, the intro text, the order of questions in the questionnaire along with the number of categories in the rating scale is tested in relation to the design of satisfaction studies. Based on the analyses specific recommendations for designing...... satisfaction studies are given....

  14. Asterisk Grade Study Report.

    Science.gov (United States)

    Kokorsky, Eileen A.

    A study was conducted at Passaic County Community College (PCCC) to investigate the operation of a grading system which utilized an asterisk (*) grade to indicate progress in a course until a letter grade was assigned. The study sought to determine the persistence of students receiving the "*" grade, the incidence of cases of students receiving…

  15. Simulation in International Studies

    Science.gov (United States)

    Boyer, Mark A.

    2011-01-01

    Social scientists have long worked to replicate real-world phenomena in their research and teaching environments. Unlike our biophysical science colleagues, we are faced with an area of study that is not governed by the laws of physics and other more predictable relationships. As a result, social scientists, and international studies scholars more…

  16. Prolactinomas : clinical studies

    NARCIS (Netherlands)

    Kars, Marleen

    2008-01-01

    Prolactinoma are treated with dopamine agonists, which are effective in reducing prolactin and tumor size. Studies reporting clinical and radiological outcome are scarce. The study described in chapter 2, assesses long-term outcome in patients treated with dopamine agonists for macroprolactinoma. An

  17. MY ENGLISH STUDY

    Institute of Scientific and Technical Information of China (English)

    孙岩; Roxanne; Lees

    2003-01-01

    I am a student of Yanshan University, majoring in English. I have studied English for a long time, which is full of (and have encountered some) special experiences (in my studies). After graduation from (a) junior (middle) school, I did not go to senior (middle) school for

  18. American Studies in Transition

    DEFF Research Database (Denmark)

    Nye, David

    Papers first given at a conference the previous year in Fåborg, Denmark, with a dual focus on 20th century America and new methods in American Studies.......Papers first given at a conference the previous year in Fåborg, Denmark, with a dual focus on 20th century America and new methods in American Studies....

  19. Pacific Studies: Quo Vadis?

    Directory of Open Access Journals (Sweden)

    Anne Holden Rønning

    2014-02-01

    Full Text Available Looking back to the past this paper discusses why Pacific studies and in particular Australasian studies became an area of interest in tertiary education in Europe. What subject areas initiated these studies, and how do past legacies shape the present? With cutbacks in higher education over the past two decades the future of interdisciplinary studies and the humanities looks bleak. At the same time due to global business and increased political communication across borders there is a vibrant interest in and need for such studies among businesses and students. For most Europeans the literature of settler countries, with their European legacy, makes access to ways of thought and culture easier than studies of countries with other mythological backgrounds. In today’s multicultural environment such studies can provide knowledge for an understanding of other cultures and increase tolerance of the ‘other’. Area studies have relevance to our situation in Europe with increased migrancy, not least as a result of Schengen and EU regulations.

  20. E-study

    Institute of Scientific and Technical Information of China (English)

    刘洪毓

    2002-01-01

    The rapid development in inforrnation technology is set to make the average home a virtual (实质上的) university campus. E-study (or online study), the latest trend in distance education, could leave university traditions suchas attending lectures,

  1. Studies of Personality Disorders

    DEFF Research Database (Denmark)

    Ronningstam, Elsa; Simonsen, Erik; Oldham, John M;

    2014-01-01

    The past 25 years have shown major advances in the studies of personality disorders. This collaborative article by the presidents, past and present, of ISSPD reflects on the progress within several significant areas of studies, i.e., assessment, neuroscience, treatment, prevention, advocacy...

  2. Study Groups in Denmark

    DEFF Research Database (Denmark)

    Hjorth, Poul G.

    2007-01-01

    Since 1998 European Study Groups have been held in Denmark, and Danish companies from LEGO and NOVO to very small high-tech firms have participated. I briefly describe the history, the organisation and the format of the Danish Study Groups, and highlight a few problem solutions....

  3. Get Oriented: Study Japan.

    Science.gov (United States)

    Parramore, Barbara M.

    1981-01-01

    Recommends that students in social studies classes be exposed to a study of Japan because of the wide array of contrasts possible between Japan and the United States. Information is presented on Japan's modernization, global status, language, decision-making processes, and ancient traditions. (DB)

  4. Electromagnetic induction studies

    Science.gov (United States)

    Hermance, J. F.

    1983-04-01

    Recent developments in electromagnetic induction studies of the lithosphere and the asthenosphere are reviewed. Attention is given to geoelectrical studies of active tectonic areas in terms of the major zones of crustal extension, the basin and range province along western regions of North America, and the Rio Grande rift. Studies have also been performed of tectonic activity around Iceland, the Salton Trough and Cerro Prieto, and the subduction zones of the Cascade Mountains volcanic belt, where magnetotelluric and geomagnetic variation studies have been done. Geomagnetic variations experiments have been reported in the Central Appalachians, and submarine electromagnetic studies along the Juan de Fuca ridge. Controlled source electromagnetic and dc resistivity investigations have been carried out in Nevada, Hawaii, and in the Adirondacks Mountains. Laboratory examinations on the conductivity of representative materials over a broad range of temperature, pressure, and chemistry are described.

  5. Critical Digital Tourism Studies

    DEFF Research Database (Denmark)

    Gyimóthy, Szilvia; Munar, Ana María

    2013-01-01

    This paper advocates the need for a critical and cross-disciplinary research agenda on the field of digital technologies and tourism. The changing virtual landscape of tourism has received increased attention by tourism scholars. However, contemporary studies on information technologies (IT......) are approached mostly from a business administration perspective and informed by conceptual frameworks developed in management and marketing. IT studies in tourism are still at a stage similar to the first advocacy phase of tourism research in general (Jafari, 1990) and are seldom inspired by relevant...... to studying digital socio-technical systems and virtual mediation in tourism. Critical Digital Tourism Studies opens a new cross-disciplinary field where the sociality of virtual tourism interactions is examined (entailing the study of structures, social rules, ideologies, power relations, sustainability...

  6. Entrepreneurship and Process Studies

    DEFF Research Database (Denmark)

    Hjorth, Daniel; Holt, Robin; Steyaert, Chris

    2015-01-01

    Process studies put movement, change and flow first; to study processually is to consider the world as restless, something underway, becoming and perishing, without end. To understand firms processually is to accept but also – and this is harder perhaps – to absorb this fluidity, to treat...... a variable as just that, a variable. The resonance with entrepreneurship studies is obvious. If any field is alive to, and fully resonant with, a processual understanding of, for example, the creation of firms, it is entrepreneurship studies. This special issue is an attempt to consider the promise...... and potential of processual approaches to studying, researching and practising entrepreneurship. The articles in the issue attest to an increasing sensitivity to processual thinking. We argue that appreciating entrepreneurial phenomena processually opens up the field to an understanding of entrepreneurship...

  7. Single Policy Study

    DEFF Research Database (Denmark)

    Kronsell, Annica; Manners, Ian James

    2015-01-01

    the relevance of single policy studies in EU research and give examples of how such research can be designed and carried out. The chapter reviews three examples of single policy studies using different methods based on EU environmental policy, the EU biofuels directive, and the EU Common Security and Defence...... Policy (CSDP). The examples are illustrative of how single policy studies can be designed to use different approaches in the analysis: multiple streams approach to policy-making; a comparative hypothesis testing; and feminist institutional theory.......Single policy studies are the most common form of European Union (EU) research. Single policy studies are widely used to understand the role of the EU in a wide variety of sectors, together with their development over time, and often offer public policy prescriptions. This chapter discusses...

  8. Effective Physics Study Habits

    Science.gov (United States)

    Zettili, Nouredine

    2011-04-01

    We discuss the methods of efficient study habits and how they can be used by students to help them improve learning physics. In particular, we deal with ideas pertaining to the most effective techniques needed to help students improve their physics study skills. These ideas were developed as part of Project IMPACTSEED (IMproving Physics And Chemistry Teaching in SEcondary Education), an outreach grant funded by the Alabama Commission on Higher Education. This project is motivated by a major pressing local need: A large number of high school physics teachers teach out of field. In the presentation, focus on topics such as the skills of how to develop long term memory, how to improve concentration power, how to take class notes, how to prepare for and take exams, how to study scientific subjects such as physics. We argue that the student who conscientiously uses the methods of efficient study habits will be able to achieve higher results than the student who does not; moreover, a student equipped with the proper study skills will spend much less time to learn a subject than a student who has no good study habits. The underlying issue here is not the quantity of time allocated to the study efforts by the student, but the efficiency and quality of actions. This work is supported by the Alabama Commission on Higher Education as part of IMPACTSEED grant.

  9. China's India Studies

    Institute of Scientific and Technical Information of China (English)

    Liu Qian

    2008-01-01

    Over the past 50 years, with the improvement of relationship between India and China, the scope of India studies in China's IR research has been broadened and the new areas of studies are being explored. The research agenda of India studies has already extended to the areas like economy, society, culture, security, national strategy and their impact on both bilateral and international relations. In this situation, the focuses of India studies in China's IR research can be mainly identified as follows: reviews on India's social, political and economic systems; analysis on the national strategy and foreign policy; Sino-Indian relations; India's relations with some international organizations. However, even though many fresh progresses have been made in India studies, the India studies in China's IR research still lag far behind the study of other important countries like the U.S., UK, Russia and Japan, and more problems and challenges will face in the coming future. The paper believes that a fuller understanding of India probably will not make China and India close friends, but it definitely will help to prevent them from becoming fierce enemies.

  10. Lead Time Study,

    Science.gov (United States)

    1982-05-01

    AD-A128 318 LEAD TIME STUDY (U) ARMY ARMAMENT RESEARCH AND DEVELOPMENT CDMMAND DOVER NJ SYSTEMS ANALYSIS DIV dI-T~~ CHU MAY 82 ARRAA 82- 3/ /l N...EhhEEE--E 1111.0 U 1 - I 1120 1.25I1,,-. 11.6 MICROCOPY RESOLUTION TESI CHARI NATIONAL BUREAU 01 STANDARDt 19t,3 A co LEAD TIME STUDY c*A JULIE CHU MAY...188 D I.-f . . .... .. - r - .. " ’- -~ L - - _ _ __ ARRAA 82-3 LEAD TIME STUDY Prepared by:_ JL CHU Reviewed by:Li t’ ( LAWRENCE J. QWUNI Chief, Sys

  11. Studying Voltage Transformer Ferroresonance

    Directory of Open Access Journals (Sweden)

    Hamid Radmanesh

    2012-09-01

    Full Text Available This study studies the effect of Circuit Breaker Shunt Resistance (CBSR, Metal Oxide Vaistor (MOV and Neutral earth Resistance (NR on the control of ferroresonance in the voltage transformer. It is expected that NR can controlled ferroresonance better than MOV and CBSR. Study has been done on a one phase voltage transformer rated 100 VA, 275 kV. The simulation results reveal that considering the CBSR and MOV exhibits a great mitigating effect on ferroresonance overvoltages, but these resistances cannot control these phenomena for all range of parameters. By applying NR to the system structure, ferroresonance has been controlled and its amplitude has been damped for all parameters values.

  12. Border region studies

    DEFF Research Database (Denmark)

    Makkonen, Teemu; Williams, Allan

    2016-01-01

    The contemporary conditions of academic capitalism exert pressures on researchers to avoid ‘peripheral’ journals and ‘unfashionable’ topics. Here an attempt is made to shed light onto the structure of one such ‘offbeat’ field, namely ‘border region studies’, by discussing its geographical...... distribution, key themes, significance and impact. The review suggests that border region studies can be considered a significant and important ‘branch’ of regional studies, which accounts for a small but increasing proportion of regional studies research particularly in Europe and North America. Four main...

  13. American Studies in Romania

    Directory of Open Access Journals (Sweden)

    Ioana Luca

    2006-01-01

    Full Text Available American Studies at the University of BucharestThe idea of teaching American Studies and founding a program in American Studies was first voiced in the long meetings of faculty and students held at the University of Bucharest soon after the collapse of the communist regime. The proposal was one of many that reflected the spirit of reform and hope for radical changes at the outset of Romania’s transition to democracy. The absence of institutional structures other than English departments and t...

  14. Building Transdisciplinary Environmental Studies

    DEFF Research Database (Denmark)

    Holm, Jesper

    We will in this paper approach the challenge of building integrated environmental studies by presenting a crude frame of analysis which take into account both the physical aspects and the social-discursive articulations of environmental problems. This framework partly mirrors the approach of our...... department (Dept. of Environment, Technology and Social Studies, Roskilde University), and has originally in another version been presented in the book “Miljøregulering - tværvidenskabelige studier (Environmental Regulation. Interdisciplinary Studies)” (Holm, Kjærgård & Pedersen eds. 1997, in Danish) written...

  15. Three-dimensional arrangement of β-tricalcium phosphate granules evaluated by microcomputed tomography and fractal analysis.

    Science.gov (United States)

    Ndiaye, Mambaye; Terranova, Lisa; Mallet, Romain; Mabilleau, Guillaume; Chappard, Daniel

    2015-01-01

    The macrophysical properties of granular biomaterials used to fill bone defects have rarely been considered. Granules of a given biomaterial occupy three-dimensional (3-D) space when packed together and create a macroporosity suitable for the invasion of vascular and bone cells. Granules of β-tricalcium phosphate were prepared using polyurethane foam technology and increasing the amount of material powder in the slurry (10, 11, 15, 18, 21 and 25 g). After sintering, granules of 1000-2000 μm were prepared by sieving. They were analyzed morphologically by scanning electron microscopy and placed in polyethylene test tubes to produce 3-D scaffolds. Microcomputed tomography (microCT) was used to image the scaffolds and to determine porosity and fractal dimension in three dimensions. Two-dimensional sections of the microCT models were binarized and used to compute classical morphometric parameters describing porosity (interconnectivity index, strut analysis and star volumes) and fractal dimensions. In addition, two newly important fractal parameters (lacunarity and succolarity) were measured. Compression analysis of the stacks of granules was done. Porosity decreased as the amount of material in the slurry increased but non-linear relationships were observed between microarchitectural parameters describing the pores and porosity. Lacunarity increased in the series of granules but succolarity (reflecting the penetration of a fluid) was maximal in the 15-18 g groups and decreased noticeably in the 25 g group. The 3-D arrangement of biomaterial granules studied by these new fractal techniques allows the optimal formulation to be derived based on the lowest amount of material, suitable mechanical resistance during crushing and the creation of large interconnected pores.

  16. Fractal dimension of trabecular bone: comparison of three histomorphometric computed techniques for measuring the architectural two-dimensional complexity.

    Science.gov (United States)

    Chappard, D; Legrand, E; Haettich, B; Chalès, G; Auvinet, B; Eschard, J P; Hamelin, J P; Baslé, M F; Audran, M

    2001-11-01

    Trabecular bone has been reported as having two-dimensional (2-D) fractal characteristics at the histological level, a finding correlated with biomechanical properties. However, several fractal dimensions (D) are known and computational ways to obtain them vary considerably. This study compared three algorithms on the same series of bone biopsies, to obtain the Kolmogorov, Minkowski-Bouligand, and mass-radius fractal dimensions. The relationships with histomorphometric descriptors of the 2-D trabecular architecture were investigated. Bone biopsies were obtained from 148 osteoporotic male patients. Bone volume (BV/TV), trabecular characteristics (Tb.N, Tb.Sp, Tb.Th), strut analysis, star volumes (marrow spaces and trabeculae), inter-connectivity index, and Euler-Poincaré number were computed. The box-counting method was used to obtain the Kolmogorov dimension (D(k)), the dilatation method for the Minkowski-Bouligand dimension (D(MB)), and the sandbox for the mass-radius dimension (D(MR)) and lacunarity (L). Logarithmic relationships were observed between BV/TV and the fractal dimensions. The best correlation was obtained with D(MR) and the lowest with D(MB). Lacunarity was correlated with descriptors of the marrow cavities (ICI, star volume, Tb.Sp). Linear relationships were observed among the three fractal techniques which appeared highly correlated. A cluster analysis of all histomorphometric parameters provided a tree with three groups of descriptors: for trabeculae (Tb.Th, strut); for marrow cavities (Euler, ICI, Tb.Sp, star volume, L); and for the complexity of the network (Tb.N and the three D's). A sole fractal dimension cannot be used instead of the classic 2-D descriptors of architecture; D rather reflects the complexity of branching trabeculae. Computation time is also an important determinant when choosing one of these methods.

  17. Pushing behavior and hemiparesis: which is critical for functional recovery in pusher patients ? Case report Comportamento de empurrar e hemiparesia: qual o déficit crítico para a recuperação funcional nos pacientes com a síndrome do empurrador? Relato de caso

    Directory of Open Access Journals (Sweden)

    Taiza E.G. Santos-Pontelli

    2007-06-01

    Full Text Available We report a sequential neuroimaging study in a 48-years-old man with a history of chronic hypertension and lacunar strokes involving the ventral lateral posterior nucleus of the thalamus. The patient developed mild hemiparesis and severe contraversive pushing behavior after an acute hemorrhage affecting the right thalamus. Following standard motor physiotherapy, the pusher behavior completely resolved 3 months after the onset and, at that time, he had a Barthel Index of 85, although mild left hemiparesis was still present. This case report illustrates that pushing behavior itself may be severely incapacitating, may occur with only mild hemiparesis and affected patients may have dramatic functional improvement (Barthel Index 0 to 85 after resolution pushing behavior without recovery of hemiparesis.Relatamos o estudo de neuroimagem seqüencial de um homem de 48 anos com história de hipertensão arterial crônica e acidentes vasculares cerebrais (AVCs lacunares nos núcleos ventral lateral posterior do tálamo. O paciente desenvolveu hemiparesia leve e síndrome do empurrador (SE grave após AVC hemorrágico no tálamo direito, sendo tratado com fisioterapia motora convencional. Três meses após o ictus, os sinais da síndrome haviam desaparecido e o paciente apresentava Índice de Barthel 85, apesar da permanência da hemiparesia leve. Este caso demonstra que a síndrome do empurrador isolada pode ser gravemente incapacitante, pode ocorrer associada a hemiparesia leve e que os pacientes com esta síndrome podem apresentar recuperação funcional importante (Índice de Barthel inicial 0 e final 85 após a resolução da SP sem alteração do grau de hemiparesia.

  18. Diversity and abundance of invertebrate epifaunal assemblages associated with gorgonians are driven by colony attributes

    KAUST Repository

    Curdia, Joao

    2015-03-20

    The present study aimed to explicitly quantify the link between the attributes of shallow-water gorgonian colonies (Octocorallia: Alcyonacea) and the ecological patterns of associated non-colonial epifaunal invertebrates. Based on multiple regression analysis, we tested the contribution of several attributes (colony height, width, and area, fractal dimension as a measure of colony complexity, lacunarity as a measure of the heterogeneity, and “colonial” epibiont cover) to abundance and taxonomic richness of associated assemblages. The results highlight the variation in the response of epifaunal assemblages to the gorgonian colony characteristics. The nature and intensity of the relationships were gorgonian species-dependent and varied from one taxonomic group to another. For both gorgonian species analyzed, the strongest predictor of species richness and abundance of the epifaunal assemblages was “colonial” epibiont cover, possibly due to a trophic effect (direct or indirect enhancement of food availability) combined with the surface available for colonization (species–area effect). Although structural complexity is usually indicated as the main driver for rich and abundant coral-associated assemblages, no significant relationship was observed between fractal dimension and the community descriptors; lacunarity, which reflects the sizes of the inter-branch spaces, was only linked to taxonomic richness in the assemblages associated with Leptogorgia lusitanica. The validity of the paradigm that structural complexity enhances biodiversity may be scale-dependent. In the case of gorgonians, the effect of complexity at the “garden” level may be more relevant than at the individual colony level. This reinforces the need for the conservation of gorgonian aggregation areas as a whole in order to preserve host diversity and size structure. © 2015 Springer-Verlag Berlin Heidelberg

  19. Relationship between the chondrocyte maturation cycle and the endochondral ossification in the diaphyseal and epiphyseal ossification centers.

    Science.gov (United States)

    Pazzaglia, Ugo E; Congiu, Terenzio; Sibilia, Valeria; Pagani, Francesca; Benetti, Anna; Zarattini, Guido

    2016-09-01

    The chondrocyte maturation cycle and endochondral ossification were studied in human, fetal cartilage Anlagen and in postnatal meta-epiphyses. The relationship between the lacunar area, the inter-territorial fibril network variations, and calcium phosphorus nucleation in primary and secondary ossification centers were assessed using light microscopy and scanning electron microscopy (SEM) morphometry. The Anlage topographic, zonal classification was derived from the anatomical nomenclature of the completely developed long bone (diaphysis, metaphyses and epiphyses). A significant increase in the chondrocyte lacunar area was documented in the Anlage of epiphyseal zones 4 and 3 to zone 2 (metaphysis) and zone 1 (diaphysis), with the highest variation from zone 2 to zone 1. An inverse reduction in the intercellular matrix area and matrix interfibrillar empty space was also documented. These findings are consistent with the osmotic passage of free cartilage water from the interfibrillar space into the swelling chondrocytes, which increased the ion concentrations to a critical threshold for mineral precipitation in the matrix. The mineralized cartilage served as a scaffold for osteoblast apposition both in primary and secondary ossification centers and in the metaphyseal growth plate cartilage, though at different periods of bone Anlage development and with distinct patterns for each zone. All developmental processes shared a common initial pathway but progressed at different rates, modes and organization in diaphysis, metaphysis and epiphysis. In the ossification phase the developing vascular supply appeared to play a key role in determining the cortical or trabecular structure of the long bones. J. Morphol. 277:1187-1198, 2016. © 2016 Wiley Periodicals, Inc.

  20. Advances in Sleep Studies

    Science.gov (United States)

    ... of this page please turn JavaScript on. Feature: Sleep Disorders Advances in Sleep Studies Past Issues / Summer 2015 ... is the director of the National Center on Sleep Disorders Research (NCSDR) in the NIH's National Heart, Lung, ...

  1. Agricultural Health Study

    Science.gov (United States)

    ... type Progress Annual Report to the Nation Cancer Portfolio Snapshots Milestones in Cancer Research & Discovery Stories of ... the Agricultural Health Study (1994–2007). Environmental Health Perspectives 2011; online May 27, doi:10.1289/ehp. ...

  2. PPB | Study Team

    Science.gov (United States)

    The Pleuropulmonary Blastoma (PPB) DICER1 Syndrome Study team is made up of researchers from the National Cancer Institute, Children¹s National Medical Center, the International Pleuropulmonary Blastoma Registry, and Washington University in St. Louis.

  3. Upper Kenai Corridor Study

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The Upper Kenai Corridor study describes and evaluates the Upper Kenai River and the land which embraces it. It also places the river corridor in its regional...

  4. Schoolground Soil Studies.

    Science.gov (United States)

    Doyle, Charles

    1978-01-01

    Outlined are simple activities for studying soil, which can be conducted in the schoolyard. Concepts include soil profiles, topsoil, soil sizes, making soil, erosion, slope, and water absorption. (SJL)

  5. The Study of Matter.

    Science.gov (United States)

    Campbell, Peter

    2000-01-01

    Reviews the booklet "The Study of Matter" produced by the Institute of Physics as part of their Shaping the Future series. This booklet is designed for teachers of chemistry, physics, design and technology, and biology. (Author/CCM)

  6. Learn about Clinical Studies

    Science.gov (United States)

    ... is to make sure that the study is ethical and that the rights and welfare of participants ... trials provide the basis for the development and marketing of new drugs, biological products, and medical devices. ...

  7. Chamberino Floodplain Management Study

    Data.gov (United States)

    Earth Data Analysis Center, University of New Mexico — The Dona Ana County Flood Commission requested the United States Department of Agriculture's Natural Resources Conservation Service to conduct a study of the...

  8. Pavement Subgrade Performance Study

    DEFF Research Database (Denmark)

    Zhang, Wei; Ullidtz, Per; Macdonald, Robin

    1998-01-01

    The report describes the second test in the Danish Road Testing Machine (RTM) under the International Pavement Subgrade Performance Study. Pavement response was measured in different layers, and compared to different theroretical values. Performance in terms of plastic strains, rutting...

  9. Exploratory studies, 1988

    Energy Technology Data Exchange (ETDEWEB)

    1989-05-01

    This report discusses the following topics: accelerator physics for the ALS; SSC support; machine investigations; mathematical techniques in particle dynamics; APIARY: B-factory studies; and two-beam accelerators and bright electron sources.

  10. Workshop I: Gender Studies

    Science.gov (United States)

    Hennessey, Eden; Kurup, Anitha; Meza-Montes, Lilia; Shastri, Prajval; Ghose, Shohini

    2015-12-01

    Participants in the Gender Studies workshop of the 5th IUPAP International Conference on Women in Physics discussed the gender question in science practice from a policy perspective, informed by investigations from the social science disciplines. The workshop's three sessions—"Equity and Education: Examining Gender Stigma in Science," "A Comparative Study of Women Scientists and Engineers: Experiences in India and the US," and "Toward Gender Equity Through Policy: Characterizing the Social Impact of Interventions—are summarized, and the resulting recommendations presented.

  11. Pregnancy: a demographic study

    OpenAIRE

    Laufer, Linda

    1987-01-01

    A retrospective study of 126 pregnant females, presenting to a chiropractor’s office was made. The average age of the patient was 29.8 years. Their backgrounds were career oriented and for the majority, it was their first pregnancy. The most frequent complaint was lower back pain. The study outlines the necessity for further data on the role of the chiropractic management of the pregnant patient.

  12. CHAROITE. EXPERIMENTAL STUDIES

    OpenAIRE

    MARCHUK MARINA V.; MEDVEDEV VLADIMIR YA.; IVANOVA LARISA A.; SOKOLOVA TATYANA S.; DANILOV BORIS S.; GLADKOCHUB DMITRY P.

    2016-01-01

    The article provides an overview of experimental studies of charoite and charoite-containing rock formation hypotheses. The authors conducted experiments to clarify charoite and host rocks interaction and study charoite transformation processes at high temperatures. A series of experiments was aimed at improving the substandard charoite samples. The experiments show the formation of polymineral reaction zones due to the contact interaction between charoite and microcline-arfvedsonite lamproph...

  13. Zambia country study

    Energy Technology Data Exchange (ETDEWEB)

    1999-09-01

    The Zambia Country Study, which was part of the Danida-funded project Climate Change Mitigation in Southern Africa: Phase 2, aimed at methodological development, national mitigation analysis and institutional capacity building in Zambia. The study comprised the following five elements: Comprehensive evaluation of national social and economic development framework for climate change; Baseline scenario(s) projection(s); Mitigation scenario(s) projection(s); Macro-economic assessment; Implementation Issues. (au) 17 refs.

  14. PET studies in epilepsy

    OpenAIRE

    Sarikaya, Ismet

    2015-01-01

    Various PET studies, such as measurements of glucose, serotonin and oxygen metabolism, cerebral blood flow and receptor bindings are availabe for epilepsy. 18Fluoro-2-deoxyglucose (18F-FDG) PET imaging of brain glucose metabolism is a well established and widely available technique. Studies have demonstrated that the sensitivity of interictal FDG-PET is higher than interictal SPECT and similar to ictal SPECT for the lateralization and localization of epileptogenic foci in presurgical patients...

  15. Tanzania country study

    Energy Technology Data Exchange (ETDEWEB)

    Meena, H.E. [Centre for Energy, Environment, Science and Technology, Dar es Salaam (Tanzania, United Republic of)

    1998-10-01

    An objective of this study is to analyse the role of the land use sectors of Tanzania (especially forestry) on mitigation of greenhouse gases. Specific emphasis is placed on the relationship between forestry and energy supply from biomass. This is a follow up study on an earlier effort which worked on mitigation options in the country without an in-depth analysis of the forestry and land use sectors. (au)

  16. Blast Overpressure Studies.

    Science.gov (United States)

    1998-05-01

    USAARL Contract Report No. CR-98-Ö3 Blast Overpressure Studies By Daniel L. Johnson EG&G Management Systems, Inc. Albuquerque, New Mexico May...Both studies were done at the Blast Overpressure-Kirtland Test Site (BOP-KTS) in New Mexico . Under a contract conducted for the USAMRMC, EG&G was... TDH -4 9 elements mounted in a David Clark 9AN/2 ear muff for added noise isolation. The calibration of the earphones was accomplished using a Bruel

  17. Definition Study PHARUS

    Science.gov (United States)

    1991-11-01

    definitie studie zijn gebruikt in het voorontwerp van het PHARUS systeem . TNO report STUDelft Page 6 ABSTRACT 3 SAMENVAlTING 4 CONTENTS 6 1 INTRODUCTION 9...University of Technology, Laboratory for Telecommunication and Remote Sensing Technology. FEL-TNO had tke lead and was responsible for the project management ...Aerospace Programs in Delft was responsible for the program management . The definition study PHARUS was started in the first half of 1988 and ended

  18. Study on Military Professionalism

    Science.gov (United States)

    1970-06-30

    Education Study. Washington: July 1966. 88. United States vs Yamashita, Action of Confirming Authority. I 7 February 1946. 89. Vroom , Victor H . Work and...I’ H N. PART II -METHODOLOGY A. MISSION. The mission assigned for this study was to assess the existing climate of professionalism in today’s Army...factors to such a degree that they were truly consequential in this assessment of the H professional climate. One can draw this conclusion from three

  19. Networked Microgrids Scoping Study

    Energy Technology Data Exchange (ETDEWEB)

    Backhaus, Scott N. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Dobriansky, Larisa [General MicroGrids, San Diego, CA (United States); Glover, Steve [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Liu, Chen-Ching [Washington State Univ., Pullman, WA (United States); Looney, Patrick [Brookhaven National Lab. (BNL), Upton, NY (United States); Mashayekh, Salman [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Pratt, Annabelle [National Renewable Energy Lab. (NREL), Golden, CO (United States); Schneider, Kevin [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Stadler, Michael [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Starke, Michael [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Wang, Jianhui [Argonne National Lab. (ANL), Argonne, IL (United States); Yue, Meng [Brookhaven National Lab. (BNL), Upton, NY (United States)

    2016-12-05

    Much like individual microgrids, the range of opportunities and potential architectures of networked microgrids is very diverse. The goals of this scoping study are to provide an early assessment of research and development needs by examining the benefits of, risks created by, and risks to networked microgrids. At this time there are very few, if any, examples of deployed microgrid networks. In addition, there are very few tools to simulate or otherwise analyze the behavior of networked microgrids. In this setting, it is very difficult to evaluate networked microgrids systematically or quantitatively. At this early stage, this study is relying on inputs, estimations, and literature reviews by subject matter experts who are engaged in individual microgrid research and development projects, i.e., the authors of this study The initial step of the study gathered input about the potential opportunities provided by networked microgrids from these subject matter experts. These opportunities were divided between the subject matter experts for further review. Part 2 of this study is comprised of these reviews. Part 1 of this study is a summary of the benefits and risks identified in the reviews in Part 2 and synthesis of the research needs required to enable networked microgrids.

  20. Photovoltaics information user study

    Energy Technology Data Exchange (ETDEWEB)

    Belew, W.W.; Wood, B.L.; Marie, T.L.; Reinhardt, C.L.

    1980-10-01

    The results of a series of telephone interviews with groups of users of information on photovoltaics (PV) are described. These results, part of a larger study on many different solar technologies, identify types of information each group needed and the best ways to get information to each group. The report is 1 of 10 discussing study results. The overall study provides baseline data about information needs in the solar community. It covers these technological areas: photovoltaics, passive solar heating and cooling, active solar heating and cooling, biomass energy, solar thermal electric power, solar industrial and agricultural process heat, wind energy, ocean energy, and advanced energy storage. An earlier study identified the information user groups in the solar community and the priority (to accelerate solar energy commercialization) of getting information to each group. In the current study only high-priority groups were examined. Results from seven PV groups respondents are analyzed in this report: DOE-Funded Researchers, Non-DOE-Funded Researchers, Researchers Working for Manufacturers, Representatives of Other Manufacturers, Representatives of Utilities, Electric Power Engineers, and Educators.

  1. Cosmos-1989 immunology studies

    Science.gov (United States)

    Sonnenfeld, Gerald

    1991-01-01

    Evidence from both human and rodent studies has indicated that alterations in immunological parameters occur after space flight. The number of flight experiments has been small, and the full breadth of immunological alterations occurring after space flight remains to be established. Among the major effects on immune responses after space flight that have been reported are: alterations in lymphocyte blastogenesis and natural killer cell activity, alterations in production of cytokines, changes in leukocyte sub-population distribution, and decreases in the ability in the ability of bone marrow cells to respond to colony stimulating factors. Changes have been reported in immunological parameters of both humans and rodents. The significance of these alterations in relation to resistance to infection remains to be established. The current study involved a determination of the effects of flight on Cosmos mission 2044 on leukocyte subset distribution and the sensitivity of bone marrow cells to colony stimulating factor-GM. A parallel study with antiorthostatic suspension was also carried out. The study involved repetition and expansion of studies carried out on Cosmos 1887.

  2. Studying Organizations on Instagram

    Directory of Open Access Journals (Sweden)

    Uta Russmann

    2016-10-01

    Full Text Available With the rise of social media platforms based on the sharing of pictures and videos, the question of how such platforms should be studied arises. Previous research on social media (content has mainly focused on text (written words and the rather text-based social media platforms Twitter and Facebook. Drawing on research in the fields of visual, political, and business communication, we introduce a methodological framework to study the fast-growing image-sharing service Instagram. This methodological framework was developed to study political parties’ Instagram accounts and tested by means of a study of Swedish political parties during the 2014 election campaign. In this article, we adapt the framework to also study other types of organizations active on Instagram by focusing on the following main questions: Do organizations only use Instagram to share one-way information, focusing on disseminating information and self-presentation? Or is Instagram used for two-way communication to establish and cultivate organization-public relationships? We introduce and discuss the coding of variables with respect to four clusters: the perception of the posting, image management, integration, and interactivity.

  3. Oxidizer Scoping Studies

    Energy Technology Data Exchange (ETDEWEB)

    Chancellor, Christopher John [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-11-07

    The purpose of this report is to present the results of the acceptable knowledge (AK) review of oxidizers present in active waste streams, provide a technical analysis of the oxidizers, and report the results of the scoping study testing. This report will determine the fastest burning oxidizer to be used in the development of a Test Plan for Preparation and Testing of Sorbents Mixed with Oxidizer found in Transuranic Waste (DWT-TP-001). The companion report, DWT-RPT-002, Sorbent Scoping Studies, contains similar information for sorbents identified during the AK review of TRU waste streams. The results of the oxidizer and sorbent scoping studies will be used to inform the QL1 test plan. The QL1 test results will support the development of a basis of knowledge document that will evaluate oxidizing chemicals and sorbents in TRU waste and provide guidance for treatment.

  4. Techniques for carcinogenicity studies.

    Science.gov (United States)

    Weisburger, E K

    1981-09-01

    Short-term tests to detect genetic, chromosomal, or DNA damage are now required by regulatory agencies for any new compound proposed for commercial production. Furthermore, full-scale carcinogenicity tests may be required for certain compounds. In this circumstance, the compound-related factors including stability, purity, physical properties, and chemical structure and reactivity must be considered. Animal factors include species and strain of test animal, route of administration, age, sex, diet, and spontaneous tumor incidence. A team of qualified investigators with experience in various disciplines is required to conduct the studies properly. Quality control measures and adherence to the code of good laboratory practice are also necessary during all phases of the study. The investment in a carcinogenicity study therefore becomes fairly substantial in terms of both time and money.

  5. Seal design alternatives study

    Energy Technology Data Exchange (ETDEWEB)

    Van Sambeek, L.L. [RE/SPEC Inc., Rapid City, SD (US); Luo, D.D.; Lin, M.S.; Ostrowski, W.; Oyenuga, D. [Parsons Brinckerhoff Quade & Douglas, Inc., San Francisco, CA (US)

    1993-06-01

    This report presents the results from a study of various sealing alternatives for the WIPP sealing system. Overall, the sealing system has the purpose of reducing to the extent possible the potential for fluids (either gas or liquid) from entering or leaving the repository. The sealing system is divided into three subsystems: drift and panel seals within the repository horizon, shaft seals in each of the four shafts, and borehole seals. Alternatives to the baseline configuration for the WIPP seal system design included evaluating different geometries and schedules for seal component installations and the use of different materials for seal components. Order-of-magnitude costs for the various alternatives were prepared as part of the study. Firm recommendations are not presented, but the advantages and disadvantages of the alternatives are discussed. Technical information deficiencies are identified and studies are outlined which can provide required information.

  6. Waarom Jesus-studies?

    Directory of Open Access Journals (Sweden)

    P. A. Geyser

    2000-01-01

    Full Text Available Why Jesus studies? Present-day historical Jesus studies are the epistemological product of what has become known as the New Historicism. The aim of the article is to emphasize two aspects of the New Historicism as epistemological approach. The one aspect focuses on the profitability of this endeavour and the other on the historical nature of the New Historicism. As far as profitability is concerned, the social standing and identity of the researcher are emphasized. Among otherthings, the social interests of the researcher are taken into account. Concerning the historical nature of this kind of research, a distinction is drawn between the Jesus of history and the Jesus of faith. The aim of the article is to gain clarity on the relationship between the Jesus of history (pre-Easter and the Jesus of faith (post-Easter. J D Crossan's exposition of the reasons for Jesus studies is followed. He distinguishes three reasons: historical, ethical and theological.

  7. International user studies

    DEFF Research Database (Denmark)

    Nielsen, Lene; Madsen, Sabine; Jensen, Iben;

    in Sydhavnen, and it is funded by InfinIT. Based on a qualitative interview study with 15 user researchers from 11 different companies, we have investigated how companies collect and present data about users on international markets. Key findings are: Companies do not collect data about end users in all....../region. The preferred data collection method is field studies. If possible, user researchers choose to go to the field themselves to gain rich insights and to control the data collection process. The main insights companies gain from international user studies are (1) that there are many similarities among end users...... across nationalities and (2) that it often is more important to focus on and take differences in market conditions into account than national culture per se. Companies are in the process of finding out how best to present the insights about international end users to their employees. However, so far...

  8. Danish Rural Eye Study

    DEFF Research Database (Denmark)

    Høeg, Tracy B; Moldow, Birgitte; Ellervik, Christina;

    2015-01-01

    PURPOSE: To determine the prevalence of amblyopia in Denmark before and after the initiation of the Danish national preschool vision screening programme. METHODS: In a population-based cross-sectional study, 3826 participants of the Danish General Suburban Population Study (GESUS) aged 20 years...... and older from a Danish rural municipality received a complete general health examination and an ophthalmological interview and examination. This study included a comprehensive ophthalmologic interview, measurement of best corrected visual acuity (BCVA) in each eye, Hirschberg's test for strabismus and two...... 45-degree retinal fundus photographs of each eye. A complete ophthalmologic examination was performed when indicated. RESULTS: The prevalence of monocular visual impairment (MVI) was 4.26% (95% CI, 3.66-4.95, n = 163). Amblyopia was the most common cause, accounting for 33%. The prevalence...

  9. NMR studies of metalloproteins.

    Science.gov (United States)

    Li, Hongyan; Sun, Hongzhe

    2012-01-01

    Metalloproteins represent a large share of the proteomes, with the intrinsic metal ions providing catalytic, regulatory, and structural roles critical to protein functions. Structural characterization of metalloproteins and identification of metal coordination features including numbers and types of ligands and metal-ligand geometry, and mapping the structural and dynamic changes upon metal binding are significant for understanding biological functions of metalloproteins. NMR spectroscopy has long been used as an invaluable tool for structure and dynamic studies of macromolecules. Here we focus on the application of NMR spectroscopy in characterization of metalloproteins, including structural studies and identification of metal coordination spheres by hetero-/homo-nuclear metal NMR spectroscopy. Paramagnetic NMR as well as (13)C directly detected protonless NMR spectroscopy will also be addressed for application to paramagnetic metalloproteins. Moreover, these techniques offer great potential for studies of other non-metal binding macromolecules.

  10. Cosmos: 1989 immunology studies

    Science.gov (United States)

    Sonnenfeld, Gerald

    1991-01-01

    The effects of flight on Cosmos mission 2044 on leukocyte subset distribution and the sensitivity of bone marrow cells to colony stimulating factor-GM were determined. A parallel study with antiorthostatic suspension was also carried out. The study involved repetition and expansion of studies performed on Cosmos 1887. Spleen and bone marrow cells were obtained from flown, vivarium control, synchronous control, and suspended rats. The cells were stained with a series of monoclonal antibodies directed against rat leukocyte cell surface antigens. Control cells were stained with a monoclonal antibody directed against an irrelevant species or were unstained. Cells were then analyzed for fluorescence using a FACSCAN flow cytometer. Bone marrow cells were placed in culture with GM-CSF in McCoy's 5a medium and incubated for 5 days. Cultures were then evaluated for the number of colonies of 50 cells or greater.

  11. Current Automotive Holometry Studies

    Science.gov (United States)

    Marchi, Mitchell M.; Snyder, D. S.

    1990-04-01

    Holometry studies of automotive body and powertrain components have become a very useful high resolution test methodology to knowledgeable Ford engineering personnel. Current examples of studies that represent the static or dynamic operational conditions of the automotive test component are presented. Continuous wave laser holometry, computer aided holometry (CAH) and pulsed laser holometry were the holometric techniques used to study the following subjects: (1) body in prime (BIP) vibration modes, (2) transmission flexplate stud-torque converter deformation due to engine torque pulses, (3) engine cylinder head and camshaft support structure deformation due to cylinder pressure and (4) engine connecting rod/cap lift-off. Static and dynamic component loading and laboratory techniques required to produce usable and valid test results are discussed along with possible conclusions for the engineering concerns.

  12. Parylene C Aging Studies.

    Energy Technology Data Exchange (ETDEWEB)

    Achyuthan, Komandoor; Sawyer, Patricia Sue.; Mata, Guillermo Adrian; White II, Gregory Von; Bernstein, Robert

    2014-09-01

    Parylene C is used in a device because of its conformable deposition and other advantages. Techniques to study Parylene C aging were developed, and "lessons learned" that could be utilized for future studies are the result of this initial study. Differential Scanning Calorimetry yielded temperature ranges for Parylene C aging as well as post-deposition treatment. Post-deposition techniques are suggested to improve Parylene C performance. Sample preparation was critical to aging regimen. Short-term (%7E40 days) aging experiments with free standing and ceramic-supported Parylene C films highlighted "lessons learned" which stressed further investigations in order to refine sample preparation (film thickness, single sided uniform coating, machine versus laser cutting, annealing time, temperature) and testing issues ("necking") for robust accelerated aging of Parylene C.

  13. Studies in Rheoencephalography (REG

    Directory of Open Access Journals (Sweden)

    Michael Bodo

    2010-01-01

    Full Text Available This article presents an overview of rheoencephalography (REG – electrical impedance measurements of the brain – and summarizes past and ongoing research to develop medical applications of REG for neuro-critical care and for primary prevention of stroke and cardiovascular disease. The availability of advanced electronics and computation has opened up the potential for use of REG technology as a noninvasive, continuous and inexpensive brain monitor for military and civilian applications. The clinical background information presented here introduces physiological and clinical environments where REG has potential for use in research and clinical settings. REG studies over the past three decades have involved in vitro and in vivo groups (animal and human, including more than 1500 measurements and related electronic and computational results and practical applications. In vitro studies helped researchers understand the flow/volume relationship between Doppler ultrasound and electrical impedance signals and supported development of REG data processing methods. In animal studies, REG was used to monitor the lower limit of cerebral blood flow (CBF autoregulation (AR using a newly developed algorithm. These animal studies also confirmed correlations between REG and measurements of carotid flow (CF and intracranial pressure (ICP. Human studies confirmed the applicability of REG for detecting cerebrovascular alteration, demonstrating the usefulness of REG in the field of stroke/cardio-vascular disease prevention. In these studies, REG was compared to known stroke risk factors and to results obtained using carotid ultrasound measurements. An intelligent REG system (Cerberus has been developed for primary stroke prevention. In these studies, the biologically relevant variables of the REG signal were pulse amplitude (minimum – maximum distance and duration of the anacrotic (rising portion of the REG pulse wave. The principal limitation of REG for

  14. Objectivist case study research

    DEFF Research Database (Denmark)

    Ridder, Hanne Mette Ochsner; Fachner, Jörg

    2016-01-01

    be achieved through the use of objectivist case study research. The strength of the case study design is that it allows for uncovering or suggesting causal relationships in real-life settings through an intensive and rich collection of data. According to Hilliard (1993), the opposite applies for extensive...... designs, in which a small amount of data is gathered on a large number of subjects. With the richness of data, the intensive design is ―the primary pragmatic reason for engaging in single-case or small N research‖ (p. 374) and for working from an idiographic rather than a nomothetic perspective....

  15. CCNA Wireless Study Guide

    CERN Document Server

    Lammle, Todd

    2010-01-01

    A complete guide to the CCNA Wireless exam by leading networking authority Todd Lammle. The CCNA Wireless certification is the most respected entry-level certification in this rapidly growing field. Todd Lammle is the undisputed authority on networking, and this book focuses exclusively on the skills covered in this Cisco certification exam. The CCNA Wireless Study Guide joins the popular Sybex study guide family and helps network administrators advance their careers with a highly desirable certification.: The CCNA Wireless certification is the most respected entry-level wireless certification

  16. Critical cyberculture studies

    CERN Document Server

    Silver, David; Jones, Steve

    2006-01-01

    Starting in the early 1990s, journalists and scholars began responding to and trying to take account of new technologies and their impact on our lives. By the end of the decade, the full-fledged study of cyberculture had arrived. Today, there exists a large body of critical work on the subject, with cutting-edge studies probing beyond the mere existence of virtual communities and online identities to examine the social, cultural, and economic relationships that take place online. Taking stock of the exciting work that is being done and positing what cyberculture's future might look like, Criti

  17. Study and Move Forward

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    @@ Chairman Mao once said: "Good good study, day day up", which can be roughly deciphered as 'study hard,keep improving'. Chinese people still remember his advice, even in the days of market-oriented reform. Today, one of the utmost urgent tasks for Chinese students is to master the English language. Chinese students start learning English from the kindergarten and English testing is normally a must for most universities. With the Olympic Games coming to Beijing in 2008, the central government has another reason to call its people to master the most popular tongue on our planet.

  18. DWPF Welder Parametric Study

    Energy Technology Data Exchange (ETDEWEB)

    Plodinec, M.J.

    1998-11-20

    After being filled with glass, DWPF canistered waste forms will be welded closed using an upset resistance welding process. This final closure weld must be leaktight, and must remain so during extended storage at SRS. As part of the DWPF Startup Test Program, a parametric study (DWPF-WP-24) has been performed to determine a range of welder operating parameters which will produce acceptable welds. The parametric window of acceptable welds defined by this study is 90,000 + 15,000 lb of force, 248,000 + 22,000 amps of current, and 95 + 15 cycles* for the time of application of the current.

  19. Photothermal degradation studies

    Science.gov (United States)

    Liang, R. H.

    1985-01-01

    Key reaction intermediates of photooxidation identified and characterized by laser flash Electron Spin Resonance (ESR) spectroscopy were discussed. Effects of temperature and ultraviolet intensity were studied in order to develop meaningful accelerated testing procedures for encapsulant evaluation. In a program to study the failure of Tedlar/ethylene vinyl acetate (EVA)/stainless steel modules, failure modes similar to those observed outdoors in real-time conditions were simulated in accelerated testing. An experimental technique was developed to quantitatively assess the extent of degradation.

  20. Reporting of teratology studies.

    Science.gov (United States)

    Barrow, Paul C; Reynaud, Lucie

    2013-01-01

    The regulatory toxicology report is an unusual document that requires a particular skill to write. The report must be clear, accurate, concise, and focused. A clear and direct writing style is required. The end-users of the report will hope to find the information they seek with as little effort as possible. Few, or none, will read the entire document. The author should aim to appease the user by obliging him to read as little text and turn as few pages as possible. This chapter gives tips and guidance on how to present the experimental data and write the narrative text in the final study report for a teratology study.

  1. Safety Study in Aviation

    OpenAIRE

    2016-01-01

    The objective of this article is to provide a brief look at safety studies, which are a necessary part of every change of system or a new system in aviation. The main focus is put on the area of air traffic management, because it affects most of the aviation stakeholders. The article begins with a description of safety and safety assessment of changes in systems. Then it discusses analysis of processes, hazard identification and risk assessment. Main part focuses on Safety studies and briefly...

  2. Morphing Terminology Study

    Energy Technology Data Exchange (ETDEWEB)

    Rose, Stuart J.; Brockman, Fred J.; Hart, Michelle L.; Engel, David W.; Valentine, Nancy B.; Calapristi, Augustin J.

    2010-06-28

    This study investigates methods of automatically identifying and characterizing significant transitions in term usage over time. Within scientific literature, the occurrence of terms reflects the use of technologies and techniques as well as the study of specific species and materials. Transitions in terminology usage may be a result of vocabulary standardization or specialization in which terms are replaced with their shorter form. They may also be a result of new applications, combinations, alternatives, or interests that result in the appearance of new or existing terminology in unexpected contexts.

  3. Studying Aid: Some Methods

    NARCIS (Netherlands)

    D.R. Gasper (Des)

    2003-01-01

    textabstractINVESTIGATING IDEAS, IDEOLOGIES AND PRACTICES This paper presents some methods for trying to make sense of international aid and of its study.1 Some of the methods may be deemed ethnographic; the others are important partners to them, but rather different. In the course of discussing q

  4. Techno-economic Study

    DEFF Research Database (Denmark)

    Sigurdsson, Halldór Matthias; Point, J.C.; Million, P.

    A techno-economic model for analysing and comparing broadband deployment strategies has been established. The resulting simulation model can compare Capital Expenditure (CAPEX) of dominating broadband technologies in different types of demographic areas. The study reveals the competitiveness...... and applicability of different access technologies in the future broadband market as well as providing sensitivity analysis of the most influential factors controlling market development....

  5. Study of Tools Interoperability

    NARCIS (Netherlands)

    Krilavičius, T.

    2007-01-01

    Interoperability of tools usually refers to a combination of methods and techniques that address the problem of making a collection of tools to work together. In this study we survey different notions that are used in this context: interoperability, interaction and integration. We point out relation

  6. The Faroese IBD Study

    DEFF Research Database (Denmark)

    Hammer, Turid; Nielsen, Kari R.; Munkholm, Pia

    2016-01-01

    from 4 to 44, and for IBDU from 2 to 21 per 100 000 [ESP]. Conclusions: The high IBD incidence was found to be a relatively new phenomenon. The observed increase is unlikely to be an artefact resulting from, for instance, better registration. Our study indicated a real and increasing disease burden...

  7. COPEWORK - COPESTRESS Workplace Study

    DEFF Research Database (Denmark)

    Ladegaard, Yun Katrine; Netterstrøm, Bo; Langer, Roy

    2012-01-01

    "COPEWORK – COPESTRESS Workplace Study" er en undersøgelse af hvad der sker på arbejdspladser, når en medarbejder sygemeldes med stress. I undersøgelsen indgik 64 ledere og arbejdsmiljørepræsentanter fra fra 38 danske arbejdspladser. Alle arbejdspladser havde haft minimum én stresssygemeldt...

  8. Studying Variation in Tunes

    NARCIS (Netherlands)

    Janssen, B.; van Kranenburg, P.

    2014-01-01

    Variation in music can be caused by different phenomena: conscious, creative manipulation of musical ideas; but also unconscious variation during music recall. It is the latter phenomenon that we wish to study: variation which occurs in oral transmission, in which a melody is taught without the help

  9. Replication studies in longevity

    DEFF Research Database (Denmark)

    Varcasia, O; Garasto, S; Rizza, T;

    2001-01-01

    In Danes we replicated the 3'APOB-VNTR gene/longevity association study previously carried out in Italians, by which the Small alleles (less than 35 repeats) had been identified as frailty alleles for longevity. In Danes, neither genotype nor allele frequencies differed between centenarians and 20...

  10. BACTERIOLOGICAL STUDY OF PYODERMA

    Directory of Open Access Journals (Sweden)

    Surekha

    2015-03-01

    Full Text Available AIM OF THE STUDY: To isolate the bacteria associated with pyodermas and to characterize the major isolate Staphylococcus aureus and to identify the MRSA. MATERIAL & METHODS: Study was conducted on 100 patients of pyodermas of all age groups and sex. Specimens were processe d by performing microscopy, culture, biochemical reaction, antibiotic susceptibility, and the major isolate Staphylococcus aureas was further screened for Methicillin Resistant Staphylococcus aureus. RESULTS: In total 100 patients fulfilling the study cri teria were evaluated. Impetigo (30% was the most common clinical type followed by folliculitis (22%, showing male preponderance. The predominant isolate was Staphylococcus aureus which was further characterized for MRSA. Out of 69 cases 5 strains were identified as MRSA. CONCLUSION: Among the 100 samples processed bacteria isolated were Staphylococcus aureus, beta haemolytic streptococci and a mixture of Staphylococcus and Streptococcus. Predominant organism causing pyoderma was Staphylococcus aureus . Present study underline the need to take efforts to develop methods for rapid detection of MRSA to prevent Hospital Acquired Infections .

  11. Resummation and Shower Studies

    CERN Document Server

    Huston, J; Sjöstrand, Torbjörn; Thomé, E

    2004-01-01

    The transverse momentum spectra of the Z and Higgs bosons are studied, as probes of the consequences of multiple parton emissions in hadronic events. Emphasis is put on constraints, present in showers, that go beyond conventional leading log. It is shown that, if such constraints are relaxed, better agreement can be obtained with experimental data and with resummation descriptions.

  12. Case Studies in Biology.

    Science.gov (United States)

    Zeakes, Samuel J.

    1989-01-01

    A case study writing exercise used in a course on parasitology was found to be a powerful learning experience for students because it involved discipline-based technical writing and terminology, brought the students in as evaluators, applied current learning, caused interaction among all students, and simulated real professional activities. (MSE)

  13. IIASA Energy Study unveiled

    Science.gov (United States)

    Richman, Barbara T.

    Meeting the energy needs of the world in 2030, when the projected population will be 8 billion, can be done, but not without international cooperation, a mix of energy technologies, and an understanding of the dependence of resources and use. That's the optimistic conclusion of the 7-year golbal energy study by the International Insitute for Applied Systems Analysis (IIASA).

  14. Repository seals requirements study

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-11-03

    The Yucca Mountain Site Characterization Project, managed by the Civilian Radioactive Waste Management System (CRWMS) Management and Operating Contractor (M and O) is conducting investigations to support the Viability Assessment and the License Application for a high-level nuclear waste repository at Yucca Mountain, Nevada. The sealing subsystem is part of the Yucca Mountain Waste Isolation System. The Yucca Mountain Site Characterization Project is currently evaluating the role of the sealing subsystem (shaft, ramp and exploratory borehole seals) in achieving the overall performance objectives for the Waste Isolation System. This report documents the results of those evaluations. This report presents the results of a repository sealing requirements study. Sealing is defined as the permanent closure of the shafts, ramps, and exploratory boreholes. Sealing includes those components that would reduce potential inflows above the repository, or that would divert flow near the repository horizon to allow vertical infiltration to below the repository. Sealing of such features as emplacement drifts was not done in this study because the current capability to calculate fracture flow into the drifts is not sufficiently mature. The objective of the study is to provide water or air flow performance based requirements for shafts, ramps, and exploratory boreholes located near the repository. Recommendations, as appropriate, are provided for developing plans, seals component testing, and other studies relating to sealing.

  15. The Study of Language

    Institute of Scientific and Technical Information of China (English)

    吴卞

    2007-01-01

    This paper analyses the study of language based on two aspects: structure and meaning.The paper first gives definition of language.Secondly,the paper summarizes the basic contents of phonology,morphology,syntax,semantics,and pragmatics.Then it focuses on the cooperative principle and the reasons why people violate the maxims and the functions of conversational implicature.

  16. Soil washing treatability study

    Energy Technology Data Exchange (ETDEWEB)

    Krstich, M.

    1995-12-01

    Soil washing was identified as a viable treatment process option for remediating soil at the FEMP Environmental Management Project (FEMP). Little information relative to the specific application and potential effectiveness of the soil washing process exists that applies to the types of soil at the FEMP. To properly evaluate this process option in conjunction with the ongoing FEMP Remedial Investigation/Feasibility Study (RI/FS), a treatability testing program was necessary to provide a foundation for a detailed technical evaluation of the viability of the process. In August 1991, efforts were initiated to develop a work plan and experimental design for investigating the effectiveness of soil washing on FEMP soil. In August 1992, the final Treatability Study Work Plan for Operable Unit 5: Soil Washing (DOE 1992) was issued. This document shall be referenced throughout the remainder of this report as the Treatability Study Work Plan (TSWP). The purpose of this treatability study was to generate data to support initial screening and the detailed analysis of alternatives for the Operable Unit 5 FS.

  17. Transfer Readiness Pilot Study.

    Science.gov (United States)

    Scott-Skillman, Thelma; And Others

    The California Community Colleges (CCC) has implemented a prototype model for determining student transfer readiness as a primary means of assessing community college transfer effectiveness. This report provides definitions of transfer readiness and guidelines for colleges participating in the CCC transfer readiness study. First, a memorandum from…

  18. Resources for Women's Studies.

    Science.gov (United States)

    Ridinger, Robert B.

    Over 120 bibliographies and other reference sources relevant to women's studies are identified in this annotated listing. Subjects include feminist scholarship, women in management, popular culture, autobiographies, other cultures and countries, history, lesbian women, women's education, the arts, politics, and rape. In addition to author, title,…

  19. Translator Studies in Retrospect

    Institute of Scientific and Technical Information of China (English)

    郭勤

    2009-01-01

    The concern about translator has run for thousands of years on which many translators and translation scholars have made comments.A rough examination of the translator within translation studies at home and abroad is expounded in a loosely chronological way as follows.

  20. SOFC interface studies

    DEFF Research Database (Denmark)

    Jacobsen, Torben; Bay, Lasse; West, Keld;

    performance and inductive hysteresis phenomena often observed in SOFC kinetic studies (\\ref{TJ01}). Fig.\\,\\ref{cath_laser} shows the YSZ surface developed below a Pt point electrode polarised at -0.10\\, V at $1000^\\circ$C for a period of 85 days. The structural as well as the compositional changes...

  1. Social Studies: Grade 8.

    Science.gov (United States)

    Manitoba Dept. of Education, Winnipeg.

    This Manitoba (Canada) curriculum guide for eighth grade social studies students contains suggested teaching strategies and learning activities in four units covering: (1) life during prehistoric and early historic times; (2) ancient civilizations; (3) life in early modern Europe; and (4) life in the modern world. Each unit includes an overview,…

  2. Course Placement Study.

    Science.gov (United States)

    Fredericksen, Marlene; Slark, Julie

    Following the implementation of a matriculation plan at Rancho Santiago College (RSC), a study was conducted to examine the appropriateness of student course placement as assessed by faculty and students and to investigate faculty's perceptions of changes in students' skill level preparation over the past few years. Questionnaires were completed…

  3. NGLW RCRA Storage Study

    Energy Technology Data Exchange (ETDEWEB)

    R. J. Waters; R. Ochoa; K. D. Fritz; D. W. Craig

    2000-06-01

    The Idaho Nuclear Technology and Engineering Center (INTEC) at the Idaho National Engineering and Environmental Laboratory contains radioactive liquid waste in underground storage tanks at the INTEC Tank Farm Facility (TFF). INTEC is currently treating the waste by evaporation to reduce the liquid volume for continued storage, and by calcination to reduce and convert the liquid to a dry waste form for long-term storage in calcine bins. Both treatment methods and activities in support of those treatment operations result in Newly Generated Liquid Waste (NGLW) being sent to TFF. The storage tanks in the TFF are underground, contained in concrete vaults with instrumentation, piping, transfer jets, and managed sumps in case of any liquid accumulation in the vault. The configuration of these tanks is such that Resource Conservation and Recovery Act (RCRA) regulations apply. The TFF tanks were assessed several years ago with respect to the RCRA regulations and they were found to be deficient. This study considers the configuration of the current tanks and the RCRA deficiencies identified for each. The study identifies four potential methods and proposes a means of correcting the deficiencies. The cost estimates included in the study account for construction cost; construction methods to minimize work exposure to chemical hazards, radioactive contamination, and ionizing radiation hazards; project logistics; and project schedule. The study also estimates the tank volumes benefit associated with each corrective action to support TFF liquid waste management planning.

  4. Acid Rain Study Guide.

    Science.gov (United States)

    Hunger, Carolyn; And Others

    Acid rain is a complex, worldwide environmental problem. This study guide is intended to aid teachers of grades 4-12 to help their students understand what acid rain is, why it is a problem, and what possible solutions exist. The document contains specific sections on: (1) the various terms used in conjunction with acid rain (such as acid…

  5. ADVANCED CUTTINGS TRANSPORT STUDY

    Energy Technology Data Exchange (ETDEWEB)

    Ergun Kuru; Stefan Miska; Nicholas Takach; Kaveh Ashenayi; Gerald Kane; Len Volk; Mark Pickell; Evren Ozbayoglu; Barkim Demirdal; Paco Vieira; Affonso Lourenco

    1999-10-15

    This report includes a review of the progress made in ACTF Flow Loop development and research during 90 days pre-award period (May 15-July 14, 1999) and the following three months after the project approval date (July15-October 15, 1999) The report presents information on the following specific subjects; (a) Progress in Advanced Cuttings Transport Facility design and development, (b) Progress report on the research project ''Study of Flow of Synthetic Drilling Fluids Under Elevated Pressure and Temperature Conditions'', (c) Progress report on the research project ''Study of Cuttings Transport with Foam Under LPAT Conditions (Joint Project with TUDRP)'', (d) Progress report on the research project ''Study of Cuttings Transport with Aerated Muds Under LPAT Conditions (Joint Project with TUDRP)'', (e) Progress report on the research project ''Study of Foam Flow Behavior Under EPET Conditions'', (f) Progress report on the instrumentation tasks (Tasks 11 and 12) (g) Activities towards technology transfer and developing contacts with oil and service company members.

  6. Studies in portal hypertension

    NARCIS (Netherlands)

    H.R. van Buuren (Henk)

    2002-01-01

    textabstractOur work focussed on one of the most frequent and serious complications of portal hypertension i.e. variceal bleeding. In particular, studies were initiated aimed at developing a more effective therapeutic strategy for the primary and secondary prevention of variceal bleeding. Aspects of

  7. Eastern Frequency Response Study

    Energy Technology Data Exchange (ETDEWEB)

    Miller, N.W.; Shao, M.; Pajic, S.; D' Aquila, R.

    2013-05-01

    This study was specifically designed to investigate the frequency response of the Eastern Interconnection that results from large loss-of-generation events of the type targeted by the North American Electric Reliability Corp. Standard BAL-003 Frequency Response and Frequency Bias Setting (NERC 2012a), under possible future system conditions with high levels of wind generation.

  8. Helias reactor studies

    Energy Technology Data Exchange (ETDEWEB)

    Beidler, C.D. [Max-Planck-Institut fuer Plasmaphysik, Garching (Germany); Grieger, G. [Max-Planck-Institut fuer Plasmaphysik, Garching (Germany); Harmeyer, E. [Max-Planck-Institut fuer Plasmaphysik, Garching (Germany); Kisslinger, J. [Max-Planck-Institut fuer Plasmaphysik, Garching (Germany); Karulin, N. [Nuclear Fusion Institute, Moscow (Russian Federation); Maurer, W. [Forschungszentrum Karlsruhe GmbH Technik und Umwelt (Germany); Nuehrenberg, J. [Max-Planck-Institut fuer Plasmaphysik, Garching (Germany); Rau, F. [Max-Planck-Institut fuer Plasmaphysik, Garching (Germany); Sapper, J. [Max-Planck-Institut fuer Plasmaphysik, Garching (Germany); Wobig, H. [Max-Planck-Institut fuer Plasmaphysik, Garching (Germany)

    1995-10-01

    The present status of Helias reactor studies is characterised by the identification and investigation of specific issues which result from the particular properties of this type of stellarator. On the technical side these are issues related to the coil system, while physics studies have concentrated on confinement, alpha-particle behaviour and ignition conditions. The usual assumptions have been made in those fields which are common to all toroidal fusion reactors: blanket and shield, refuelling and exhaust, safety and economic aspects. For blanket and shield sufficient space has been provided, a detailed concept will be developed in future. To date more emphasis has been placed on scoping and parameter studies as opposed to fixing a specific set of parameters and providing a detailed point study. One result of the Helias reactor studies is that physical dimensions are on the same order as those of tokamak reactors. However, it should be noticed that this comparison is difficult in view of the large spectrum of tokamak reactors ranging from a small reactor like Aries, to a large device such as SEAFP. The notion that the large aspect ratio of 10 or more in Helias configurations also leads to large reactors is misleading, since the large major radius of 22 m is compensated by the average plasma radius of 1.8 m and the average coil radius of 5 m. The plasma volume of 1400 m{sup 3} is about the same as the ITER reactor and the magnetic energy of the coil system is about the same or even slightly smaller than envisaged in ITER. (orig.)

  9. STUDY OF ENTEROCUTANEOUS FISTULA

    Directory of Open Access Journals (Sweden)

    Arti

    2015-03-01

    Full Text Available BACKGROUND: A fistula is defined as abnormal communication between two epithelial surfaces . 1 Enterocutaneous fistula is defined as abnormal communication between hollow organ and skin. They are classified as congenital or acquired. We have excluded congenital and internal fistulas. We have also excluded esophageal, urinary, p ancreatic and biliary fistulas as their management is complex and differs significantly from enterocutaneous fistulas. AIM: 1. Study of aetiology, pathophysiology and management of enterocutaneous fistula. To evaluate previously laid principles of management of enterocutaneous fistula. 2. To assess the feasibility of early intervention safety and outcome as the conservative long term treatment appears to be cost prohibitive. 3. To study morbidity and mortality related to enterocutaneous fistula. MATERIAL AND METHODS: In all, 50 cases of enterocutaneous fistula were studied during a period from June 2012 to N ovember 2014 at a Government tertiary care C entre. Both, patients referred from other centres with post - operative fistulas and fistulas developed in this institute after surgeries or spontaneously were included in the study after fulfilling the inclusion and exclusion criteria. RESULT S : The maximum numbers of cases were between 39 - 48 years of age group. Spontaneous closure was achieved in 72.7% and surgical closure in 76.7% of the patients Vacuum assisted closure was achieved in 66.66% of the patients in whom VAC was used. Of the patients in whom octreotide was used closure was achieved in 66.66% of the patients. The association between serum albumin levels and fistula healing and between fistula output and mortality were statistically significant. Overall mortality in this study was 26% with 44.44% among referred cases and 15.625% among institutional cases.

  10. ADVANCED CUTTINGS TRANSPORT STUDY

    Energy Technology Data Exchange (ETDEWEB)

    Troy Reed; Stefan Miska; Nicholas Takach; Kaveh Ashenayi; Gerald Kane; Mark Pickell; Len Volk; Mike Volk; Barkim Demirdal; Affonso Lourenco; Evren Ozbayoglu; Paco Vieira; Lei Zhou

    2000-01-30

    This is the second quarterly progress report for Year 2 of the ACTS project. It includes a review of progress made in Flow Loop development and research during the period of time between Oct 1, 2000 and December 31, 2000. This report presents a review of progress on the following specific tasks: (a) Design and development of an Advanced Cuttings Transport Facility (Task 2: Addition of a foam generation and breaker system), (b) Research project (Task 6): ''Study of Cuttings Transport with Foam Under LPAT Conditions (Joint Project with TUDRP)'', (c) Research project (Task 7): ''Study of Cuttings Transport with Aerated Muds Under LPAT Conditions (Joint Project with TUDRP)'', (d) Research project (Task 8): ''Study of Flow of Synthetic Drilling Fluids Under Elevated Pressure and Temperature Conditions'', (e) Research project (Task 9): ''Study of Foam Flow Behavior Under EPET Conditions'', (f) Research project (Task 10): ''Study of Cuttings Transport with Aerated Mud Under Elevated Pressure and Temperature Conditions'', (g) Research on instrumentation tasks to measure: Cuttings concentration and distribution in a flowing slurry (Task 11), and Foam properties while transporting cuttings. (Task 12), (h) Development of a Safety program for the ACTS Flow Loop. Progress on a comprehensive safety review of all flow-loop components and operational procedures. (Task 1S). (i) Activities towards technology transfer and developing contacts with Petroleum and service company members, and increasing the number of JIP members. The tasks Completed During This Quarter are Task 7 and Task 8.

  11. PET studies in epilepsy.

    Science.gov (United States)

    Sarikaya, Ismet

    2015-01-01

    Various PET studies, such as measurements of glucose, serotonin and oxygen metabolism, cerebral blood flow and receptor bindings are availabe for epilepsy. (18)Fluoro-2-deoxyglucose ((18)F-FDG) PET imaging of brain glucose metabolism is a well established and widely available technique. Studies have demonstrated that the sensitivity of interictal FDG-PET is higher than interictal SPECT and similar to ictal SPECT for the lateralization and localization of epileptogenic foci in presurgical patients refractory to medical treatments who have noncontributory EEG and MRI. In addition to localizing epileptogenic focus, FDG-PET provide additional important information on the functional status of the rest of the brain. The main limitation of interictal FDG-PET is that it cannot precisely define the surgical margin as the area of hypometabolism usually extends beyond the epileptogenic zone. Various neurotransmitters (GABA, glutamate, opiates, serotonin, dopamine, acethylcholine, and adenosine) and receptor subtypes are involved in epilepsy. PET receptor imaging studies performed in limited centers help to understand the role of neurotransmitters in epileptogenesis, identify epileptic foci and investigate new treatment approaches. PET receptor imaging studies have demonstrated reduced (11)C-flumazenil (GABAA-cBDZ) and (18)F-MPPF (5-HT1A serotonin) and increased (11)C-cerfentanil (mu opiate) and (11)C-MeNTI (delta opiate) bindings in the area of seizure. (11)C-flumazenil has been reported to be more sensitive than FDG-PET for identifying epileptic foci. The area of abnormality on GABAAcBDZ and opiate receptor images is usually smaller and more circumscribed than the area of hypometabolism on FDG images. Studies have demonstrated that (11)C-alpha-methyl-L-tryptophan PET (to study synthesis of serotonin) can detect the epileptic focus within malformations of cortical development and helps in differentiating epileptogenic from non-epileptogenic tubers in patients with tuberous

  12. Options Study - Phase II

    Energy Technology Data Exchange (ETDEWEB)

    R. Wigeland; T. Taiwo; M. Todosow; W. Halsey; J. Gehin

    2010-09-01

    The Options Study has been conducted for the purpose of evaluating the potential of alternative integrated nuclear fuel cycle options to favorably address the issues associated with a continuing or expanding use of nuclear power in the United States. The study produced information that can be used to inform decisions identifying potential directions for research and development on such fuel cycle options. An integrated nuclear fuel cycle option is defined in this study as including all aspects of the entire nuclear fuel cycle, from obtaining natural resources for fuel to the ultimate disposal of used nuclear fuel (UNF) or radioactive wastes. Issues such as nuclear waste management, especially the increasing inventory of used nuclear fuel, the current uncertainty about used fuel disposal, and the risk of nuclear weapons proliferation have contributed to the reluctance to expand the use of nuclear power, even though it is recognized that nuclear power is a safe and reliable method of producing electricity. In this Options Study, current, evolutionary, and revolutionary nuclear energy options were all considered, including the use of uranium and thorium, and both once-through and recycle approaches. Available information has been collected and reviewed in order to evaluate the ability of an option to clearly address the challenges associated with the current implementation and potential expansion of commercial nuclear power in the United States. This Options Study is a comprehensive consideration and review of fuel cycle and technology options, including those for disposal, and is not constrained by any limitations that may be imposed by economics, technical maturity, past policy, or speculated future conditions. This Phase II report is intended to be used in conjunction with the Phase I report, and much information in that report is not repeated here, although some information has been updated to reflect recent developments. The focus in this Options Study was to

  13. Heliostat cost optimization study

    Science.gov (United States)

    von Reeken, Finn; Weinrebe, Gerhard; Keck, Thomas; Balz, Markus

    2016-05-01

    This paper presents a methodology for a heliostat cost optimization study. First different variants of small, medium sized and large heliostats are designed. Then the respective costs, tracking and optical quality are determined. For the calculation of optical quality a structural model of the heliostat is programmed and analyzed using finite element software. The costs are determined based on inquiries and from experience with similar structures. Eventually the levelised electricity costs for a reference power tower plant are calculated. Before each annual simulation run the heliostat field is optimized. Calculated LCOEs are then used to identify the most suitable option(s). Finally, the conclusions and findings of this extensive cost study are used to define the concept of a new cost-efficient heliostat called `Stellio'.

  14. E85 Dispenser Study

    Energy Technology Data Exchange (ETDEWEB)

    Moriarty, K.; Johnson, C.; Sears, T.; Bergeron, P.

    2009-12-01

    This study reviews E85 dispensing infrastructure advances and issues and evaluates the geographic concentration of flexible fuel vehicles (FFVs), E85 stations, ethanol production facilities, and E85 suppliers. Costs, space, financial incentives, and barriers to adding E85 fueling equipment at existing stations are also assessed. This study found that E85 is increasingly available in the U.S. in half of the states; however, the other half have minimal or no E85 fueling options. Despite these gains, E85 is only available at 1% of U.S. gasoline stations. Ethanol production reached 9.5 billion gallons in 2008, but less than 1% is consumed as E85. FFVs have not reached a significant concentration in any county, metropolitan area, or state.

  15. Botswana country study

    Energy Technology Data Exchange (ETDEWEB)

    1999-09-01

    This study was carried out in Botswana, Tanzania and Zambia as part of the project `Climate Change Mitigation in Southern Africa` funded by the Danish International Development Agency (Danida). The project was conducted parallel to the UNEP/GEF project `Economics of Greenhouse Gas Limitations` which involved 8 other developing countries and 2 regional projects in Latin America and the SADC region. The limitation of greenhouse gas (GHG) emissions is a complex issue, intimately connected with economic development at local, national, regional and global levels. Key economic sectors such as energy, agriculture, industry and forestry all produce GHGs, and are likely to be affected directly and indirectly by any mitigation policy. The UNEP Greenhouse Gas Abatement Costing Studies, initiated in 1991, attempted to address these complex issues, developing a methodological framework and testing it through practical application in ten countries. (EHS) 28 refs.

  16. Southeast continental shelf studies

    Energy Technology Data Exchange (ETDEWEB)

    Menzel, D.W.

    1979-02-12

    Research efforts on the southeast continental shelf currently describe the manner in which fluctuations in Gulf Stream motion influence biological and chemical processes. Current meter arrays are maintained in the Georgia Bight and in Onslow Bay to describe general circulation patterns and to identify forcing functions. biological studies describe processes affecting temporal and spatial variations on the shelf and have attempted to track the biological history of intruded Gulf Stream water masses. Chemical studies examine the influence of both physical and biological variables on the distribution and fate of trace elements. The current state of knowledge is reviewed, the hypotheses developed and are described, a rationale for testing these hypotheses is given. 1 figure, 1 table.

  17. Innovation and Entrepreneurship Studies

    DEFF Research Database (Denmark)

    Landström, Hans; Åström, Fredrik; Harirchi, Gouya

    2015-01-01

    As we have moved towards a more knowledge intensive society, innovation and industrial dynamics have grown in importance over the last 40-50 years. We are frequently using concepts such as innovation and entrepreneurship, and the way we perceive and define these concepts will to a high extent...... influence our way of thinking and acting. Depending on the way we define these concepts, we will tend to use different knowledge-bases when acting as policy-makers, or as researchers. Therefore, it becomes important to elaborate on the knowledge bases that we have within the fields of innovation...... and entrepreneurship. This study we elaborate on the question: Can innovation and entrepreneurship be seen as one or two fields of research? We will elaborate on this issue by comparing the core works in innovation and entrepreneurship studies respectively, as identified by Fagerberg et al. (Research Policy 41...

  18. Studies on seismic source

    Institute of Scientific and Technical Information of China (English)

    李世愚; 陈运泰

    2003-01-01

    During the period of 1999~2002, the Chinese seismologists made a serious of developments in the study on seismic sources including observations, experiments and theory. In the field of observation, the methods of the accuracy location of earthquake sources, the inversion of seismic moment tensor and the mechanism of earthquake source are improved and developed. A lot of important earthquake events are studied by using these methods. The rupture processes of these events are inverted and investigated combined with the local stress fields and the tectonic moment by using the measurements of surface deformation. In the fields of experiments and theory, many developments are obtained in cause of seismic formation, condition of stress and tectonics, dynamics of earthquake rupture, rock fracture and nucleation of strong earthquakes.

  19. Fullerton Virtual Twin Study.

    Science.gov (United States)

    Segal, Nancy L

    2006-12-01

    Virtual twins (VTs; same-age unrelated siblings reared together from early infancy) have been studied at California State University (CSU), Fullerton since 1991. The current sample includes over 130 pairs. Past and current research have research have focused on siblings' similarities and differences in general intelligence and body size. Future research in these areas will continue as new pairs continue to be identified. These studies will be supplemented by analyses of personality, social relations and adjustment using monozygotic (MZ) twins, dizygotic (DZ) twins, full siblings and friends, as well as new VTs, who have participated in Twins, Adoptees, Peers and Siblings (TAPS), a collaborative project conducted between CSU Fullerton and the University of San Francisco, from 2002 to 2006.

  20. World Biofuels Study

    Energy Technology Data Exchange (ETDEWEB)

    Alfstad,T.

    2008-10-01

    This report forms part of a project entitled 'World Biofuels Study'. The objective is to study world biofuel markets and to examine the possible contribution that biofuel imports could make to help meet the Renewable Fuel Standard (RFS) of the Energy Independence and Security Act of 2007 (EISA). The study was sponsored by the Biomass Program of the Assistant Secretary for Energy Efficiency and Renewable Energy (EERE), U.S. Department of Energy. It is a collaborative effort among the Office of Policy and International Affairs (PI), Department of Energy and Oak Ridge National Laboratory (ORNL), National Renewable Energy Laboratory (NREL) and Brookhaven National Laboratory (BNL). The project consisted of three main components: (1) Assessment of the resource potential for biofuel feedstocks such as sugarcane, grains, soybean, palm oil and lignocellulosic crops and development of supply curves (ORNL). (2) Assessment of the cost and performance of biofuel production technologies (NREL). (3) Scenario-based analysis of world biofuel markets using the ETP global energy model with data developed in the first parts of the study (BNL). This report covers the modeling and analysis part of the project conducted by BNL in cooperation with PI. The Energy Technology Perspectives (ETP) energy system model was used as the analytical tool for this study. ETP is a 15 region global model designed using the MARKAL framework. MARKAL-based models are partial equilibrium models that incorporate a description of the physical energy system and provide a bottom-up approach to study the entire energy system. ETP was updated for this study with biomass resource data and biofuel production technology cost and performance data developed by ORNL and NREL under Tasks 1 and 2 of this project. Many countries around the world are embarking on ambitious biofuel policies through renewable fuel standards and economic incentives. As a result, the global biofuel demand is expected to grow very

  1. Electron microscope studies

    Energy Technology Data Exchange (ETDEWEB)

    Crewe, A.V.; Kapp, O.H.

    1991-06-01

    This year our laboratory has continued to make progress in the design of electron-optical systems, in the study of structure-function relationships of large multi-subunit proteins, in the development of new image processing software and in achieving a workable sub-angstrom STEM. We present an algebraic approach to the symmetrical Einzel (unipotential) lens wherein we simplify the analysis by specifying a field shape that meets some preferred set of boundary or other conditions and then calculate the fields. In a second study we generalize this approach to study of three element electrostatic lenses of which the symmetrical Einzel lens is a particular form. The purpose is to develop a method for assisting in the design of a lens for a particular purpose. In our biological work we study a stable and functional dodecameric complex of globin chains from the hemoglobin of Lumbricus terrestris. This is a complex lacking the linker'' subunit first imaged in this lab and required for maintenance of the native structure. In addition, we do a complete work-up on the hemoglobin of the marine polychaete Eudistylia vancouverii demonstrating the presence of a hierarchy of globin complexes. We demonstrate stable field-emission in the sub-angstrom STEM and the preliminary alignment of the beam. We continue our exploration of a algorithms for alignment of sequences of protein and DNA. Our computer facilities now include four second generation RISC workstations and we continue to take increasing advantage of the floating-point and graphical performance of these devices.

  2. a prospective study

    OpenAIRE

    Rörster, Elisa geb. Pätel

    2012-01-01

    Bulk fractures only occur on very rare occasions in bilayered all-ceramic crowns, where as veneer fractures, above all chippings, still present a frequent amount of clinical complications. The purpose of the current prospective study was to examine the clinical performance of an anatomically modified framework for a period of two years. All crowns were manufactured following the Cercon process (DeguDent GmbH, Hanau). As is common practice, the frameworks for the control group were made of ...

  3. Case Studies - Cervical Cancer

    Centers for Disease Control (CDC) Podcasts

    2010-10-15

    Dr. Alan Waxman, a professor of obstetrics and gynecology at the University of New Mexico and chair of the American College of Obstetricians and Gynecologists (ACOG) committee for the underserved, talks about several case studies for cervical cancer screening and management.  Created: 10/15/2010 by National Center for Chronic Disease Prevention and Health Promotion (NCCDPHP), Division of Cancer Prevention and Control (DCPC).   Date Released: 6/9/2010.

  4. CLIC Final Focus Studies

    CERN Document Server

    Tomás, R; Schulte, Daniel; Zimmermann, Frank

    2006-01-01

    The CLIC final focus system has been designed based on the local compensation scheme proposed by P. Raimondi and A. Seryi. However, there exist important chromatic aberrations that deteriorate the performance of the system. This paper studies the optimization of the final focus based on the computation of the higher orders of the map using MAD-X and PTC. The use of octupole tail folding to reduce the size of the halo in the locations with aperture limitations is also discussed.

  5. Master Study: Ceramics

    Science.gov (United States)

    Clark, Kelly

    2004-01-01

    In painting and drawing classes, it is typical to ask students to work directly from a master. It is one way to study composition techniques, and to become familiar with classical style firsthand. In museums, easels are set up as artists work, not in an attempt to copy or plagiarize, but in an attempt to be part of history by participating in it.…

  6. Giornata di Studi Paleontologici

    Directory of Open Access Journals (Sweden)

    Davide Bassi

    2005-09-01

    Full Text Available This book results fromk one-day meeting "Giornata di Studi Paleontologici Prof.ssa C. Loriga Broglio", held in Ferrara on June 18th, 2004 and dedicated to Prof. Carmen Loriga Broglio who was full Professor of Paleontology and Paleoecology at the University of Ferrara.This special volume includes twelve papers dealing with systematic paleontology of calcified cyanobacteria, invertebrates (sponges and vertebrates (fishes, taphonomy, biostratigraphy, paleoecology and paleobiogeography.

  7. Sorbent Scoping Studies

    Energy Technology Data Exchange (ETDEWEB)

    Chancellor, Christopher John [Los Alamos National Lab. (LANL), Carlsbad, NM (United States). Difficult Waste Team

    2016-11-14

    The Los Alamos National Laboratory – Carlsbad Operations (LANL-CO) office was tasked by the DOE CBFO, Office of the Manager to: • Perform a review of the acceptable knowledge (AK) to identify the oxidizers and sorbents in transuranic (TRU) waste streams. • Conduct scoping studies on the oxidizers and sorbents identified in AK review to inform the Quality Level 1 (QL1) testing. • Conduct a series of QL1 tests to provide the scientific data to support a basis of knowledge document for determining the criteria for: 1) accepting waste at the Waste Isolation Pilot Plant (WIPP) without treatment, 2) determining waste that will require treatment, and 3) if treatment is required, how the treatment must be performed. The purpose of this report is to present the results of the AK review of sorbents present in active waste streams, provide a technical analysis of the sorbent list, report the results of the scoping studies for the fastest burning organic sorbent, and provide the list of organic and inorganic sorbents to be used in the development of a Test Plan for Preparation and Testing of Sorbents Mixed with Oxidizer found in Transuranic Waste (DWT-TP-001). The companion report, DWT-RPT-001, Oxidizer Scoping Studies, has similar information for oxidizers identified during the AK review of TRU waste streams. The results of the oxidizer and sorbent scoping studies will be used to inform the QL1 test plan. The QL1 test results will support the development of a basis of knowledge document that will evaluate oxidizing chemicals and sorbents in TRU waste and provide guidance for treatment.

  8. American Studies in Russia

    Directory of Open Access Journals (Sweden)

    Olga Antsyferova

    2006-01-01

    Full Text Available Interest in the USA, both general and specifically academic, has always existed in Russia, with its own ups and downs. But American studies as an academic discipline started gaining its popularity probably after WWII when there sporadically started to emerge the ever-increasing number of academic books, articles and dissertations in literary and historical research on the USA, the main centers of which were founded at the Academic Research Institute of the USA and Canada, headed by academicia...

  9. Food Fortification Stability Study

    Science.gov (United States)

    Sirmons, T. A.; Cooper, M. R.; Douglas, G. L.

    2017-01-01

    This study aimed to assess the stability of vitamin content, sensory acceptability and color variation in fortified spaceflight foods over a period of two years. Findings will help to identify optimal formulation, processing, and storage conditions to maintain stability and acceptability of commercially available fortification nutrients. Changes in food quality were monitored to indicate whether fortification affects quality over time (compared to the unfortified control), thus indicating their potential for use on long-duration missions.

  10. Phenomenological Studies in Micromechanics

    Science.gov (United States)

    1988-09-30

    determined. Surprisingly high localized strains have been identified between plies. (ii) Edge effect stresses have been isolated and quantified...studies of the edges of the specimen in Fig. 11 indicate the presence of high (corner) edge effect shear stresses. These are shown on an expanded...cube are shown in Fig. 22. S In addition to the significant edge effect of Fig. 22, the following residual deformations and co-efficients of thermal

  11. Electrochemical corrosion studies

    Science.gov (United States)

    Knockemus, W. W.

    1986-01-01

    The objective was to gain familiarity with the Model 350 Corrosion Measurement Console, to determine if metal protection by grease coatings can be measured by the polarization-resistance method, and to compare corrosion rates of 4130 steel coated with various greases. Results show that grease protection of steel may be determined electrochemically. Studies were also conducted to determine the effectiveness of certain corrosion inhibitors on aluminum and steel.

  12. Purified water quality study

    Energy Technology Data Exchange (ETDEWEB)

    Spinka, H.; Jackowski, P.

    2000-04-03

    Argonne National Laboratory (HEP) is examining the use of purified water for the detection medium in cosmic ray sensors. These sensors are to be deployed in a remote location in Argentina. The purpose of this study is to provide information and preliminary analysis of available water treatment options and associated costs. This information, along with the technical requirements of the sensors, will allow the project team to determine the required water quality to meet the overall project goals.

  13. Indonesia country study

    Energy Technology Data Exchange (ETDEWEB)

    1999-09-01

    This study demonstrated the use of MARKAL model in carbon mitigation analysis for both energy and forestry sector. Four scenarios were used namely: 1. EbFb (baseline scenario). In this scenario, mitigation technologies in the energy sector were not included in the model and no target was set up for increasing net carbon uptake by forest activities. 2. EmFb. Mitigation technologies in the energy sector were included with the target of reducing cumulative net carbon emission by about 13% and activities in the forestry sectors were the same as those in baseline. 3. EbFm. Mitigation technologies in the energy sector were not included and the forestry activities were targeted to increase the carbon uptake so that the cumulative net carbon emission decreased by 13%. 4. EmFm. Mitigation technologies in the energy sector were included as well as forestry sector with target of reducing cumulative net carbon emission by about 35%. This study indicates that the MARKAL model has the potential to be used for mitigation analysis for both energy and forestry sectors. However, there are some limitations encountered during the study. The program is not able to accommodate the delayed emission from the forestry sector in a manner consistent to the treatment of emissions in the energy sector. In addition, there are some technical problems that still need to be resolved such as the inclusion of soil carbon uptake calculation in the model and the verification of carbon uptake calculation. In this study, all carbon uptakes was assumed to occur at the time of planting. (EHS) 37 refs.

  14. Food Fortification Stability Study

    Science.gov (United States)

    Sirmons, T. A.; Cooper, M. R.; Douglas, G. L.

    2016-01-01

    This study aims to assess the stability of vitamin content, sensory acceptability and color variation in fortified spaceflight foods over a period of 2 years. Findings will identify optimal formulation, processing, and storage conditions to maintain stability and acceptability of commercially available fortification nutrients. Changes in food quality are being monitored to indicate whether fortification affects quality over time (compared to the unfortified control), thus indicating their potential for use on long-duration missions.

  15. SEDIMENTATION AND EROSION STUDIES

    Institute of Scientific and Technical Information of China (English)

    Chih Ted YANG

    2005-01-01

    @@ The river systems observed today is the cumulative result of surface, rill, and gully erosion, and sediment transport, scour, and deposition. The divisions of approach between these two related areas are man-made, and are not based on sound science. Most of the erosion studies are done by geologists and agricultural engineers who are concerned of the surface, rill, and gully erosion and the loss of agricultural land productivity. Hydraulic engineers are more interested in the study of sediment transport, scour, and deposition, and their impacts on river engineering and hydraulic structures in rivers and reservoirs. Erosion studies are often based on empirical relationships or field data to determinate the annual sediment yield from a watershed. On the other hand, hydraulic engineers focus their attention on solving equations based on assumed initial and boundary conditions with a time scale of days, hours, or seconds. Both approaches have their complementary strengths and weaknesses. It is important to provide a forum for specialists in both areas to communicate, exchange ideas, and learn from each other.

  16. The safeguards options study

    Energy Technology Data Exchange (ETDEWEB)

    Hakkila, E.A.; Mullen, M.F.; Olinger, C.T.; Stanbro, W.D. [Los Alamos National Lab., NM (United States); Olsen, A.P.; Roche, C.T.; Rudolph, R.R. [Argonne National Lab., IL (United States); Bieber, A.M.; Lemley, J. [Brookhaven National Lab., Upton, NY (United States); Filby, E. [Idaho National Engineering Lab., Idaho Falls, ID (United States)] [and others

    1995-04-01

    The Safeguards Options Study was initiated to aid the International Safeguards Division (ISD) of the DOE Office of Arms Control and Nonproliferation in developing its programs in enhanced international safeguards. The goal was to provide a technical basis for the ISD program in this area. The Safeguards Options Study has been a cooperative effort among ten organizations. These are Argonne National Laboratory, Brookhaven National Laboratory, Idaho National Engineering Laboratory, Lawrence Livermore National Laboratory, Los Alamos National Laboratory, Mound Laboratory, Oak Ridge National Laboratory, Pacific Northwest Laboratories, Sandia National Laboratories, and Special Technologies Laboratory. Much of the Motivation for the Safeguards Options Study is the recognition after the Iraq experience that there are deficiencies in the present approach to international safeguards. While under International Atomic Energy Agency (IAEA) safeguards at their declared facilities, Iraq was able to develop a significant weapons program without being noticed. This is because negotiated safeguards only applied at declared sites. Even so, their nuclear weapons program clearly conflicted with Iraq`s obligations under the Nuclear Nonproliferation Treaty (NPT) as a nonnuclear weapon state.

  17. Operations dashboard: comparative study

    Science.gov (United States)

    Ramly, Noor Nashriq; Ismail, Ahmad Zuhairi; Aziz, Mohd Haris; Ahmad, Nurul Haszeli

    2011-10-01

    In this present days and age, there are increasing needs for companies to monitor application and infrastructure health. Apart from having proactive measures to secure their application and infrastructure, many see monitoring dashboards as crucial investment in disaster preparedness. As companies struggle to find the best solution to cater for their needs and interest for monitoring their application and infrastructure's health, this paper summarizes the studies made on several known off-the-shelf operations dashboard and in-house developed dashboard. A few criteria of good dashboard are collected from previous studies carried out by several researchers and rank them according to importance and business needs. The finalized criteria that will be discussed in later sections are data visualization, performance indicator, dashboard personalization, audit capability and alert/ notification. Comparative studies between several popular dashboards were then carried out to determine whether they met these criteria that we derived from the first exercise. The findings hopefully can be used to educate and provide an overview of selecting the best IT application and infrastructure operations dashboard that suit business needs, thus become the main contribution of this paper.

  18. Review - Critical Han Studies

    Directory of Open Access Journals (Sweden)

    Zhiguo Ye

    2013-12-01

    Full Text Available Review of: Thomas Mullaney, James Leibold, Stéphane Gros, and Eric Armand Vanden Bussche (eds. 2012. Critical Han Studies: The History, Representation, and Identity of China's Majority. Berkeley, Calif: University of California Press. This path-breaking volume is an academic collaboration that emerged out of the "Critical Han Studies Conference and Workshop" at Stanford University in April 2008. Eleven scholars contributed to the question of what it means to be 'Han' in China, both historically and at present. Constituting over ninety percent of China's population, the Han are not only the largest ethnic group in China, but are also one of the largest categories of collective identity in the world. Despite this, the dominant Han group has so far eluded careful scholarly scrutiny, with the Han often referred to as an unmarked majority category in contemporary China. This volume challenges such conventional views by conceptualizing new interdisciplinary approaches to the question of Hanness. The eleven essays of the volume are divided into three themes: 'Han and China', 'The Problem of Han Origins', and 'The Problem of Han Formations'. The first theme, comprised of four essays, analyzes the ties that bind the category of Han to those of Chinese ethnicity, race, and polity. Kevin Carrico in "Recentering China: The Cantonese in and Beyond the Han" questions a single, unitary Hanness that he believes conceals "countless other perceived and imagined lines of differentiation" (25. The study examines how multiple identities...

  19. The Hi Five study

    DEFF Research Database (Denmark)

    Johansen, Anette; Denbæk, Anne Maj; Bonnesen, Camilla Thørring;

    2015-01-01

    and almost none of them are conducted as randomized controlled trials. The overall aim of the Hi Five study was to develop, implement and evaluate a multi-component school-based intervention to improve hand hygiene and well-being and to reduce the prevalence of infections among school children...... in intervention schools by 20% compared to control schools. This paper describes the development and the evaluation design of Hi Five. METHODS/DESIGN: The Hi Five study was designed as a tree-armed cluster-randomized controlled trial. A national random sample of schools (n = 44) was randomized to one of two...... intervention groups (n = 29) or to a control group with no intervention (n = 15). A total of 8,438 six to fifteen-year-old school children were enrolled in the study. The Hi Five intervention consisted of three components: 1) a curriculum component 2) mandatory daily hand washing before lunch 3) extra cleaning...

  20. Tanzania country study

    Energy Technology Data Exchange (ETDEWEB)

    1999-09-01

    Objectives of this study are to analyse the role of the land use sectors of Tanzania (especially forestry) on mitigation of greenhouse gases. Specific emphasis is placed on the relationship between forestry and energy supply from biomass, as well as other forestry products. This is a follow up study on an earlier effort which worked on mitigation options in the country without and in-depth analysis of the forestry and land use sectors. Analysis of the mitigation scenario has been based on Comprehensive Mitigation Analysis (COMAP). This study has analysed the forestry and land use sector behaviour on the basis of the current policies on land and environment. Furthermore three scenarios have been developed on the basis of what is expected to happen in the sectors, the worse scenario being a catastrophic one where if things takes the business as usual trend then the forest resources will easily be depleted. The TFAP scenario takes into account the implementation of the current plans as scheduled while the mitigation scenario takes into account the GHG mitigation in the implementation of the plans. A Comprehensive Mitigation Analysis Process (COMAP) has been used to analyse the GHG and cost implications of the various programmes under the mitigation scenario. (au) 30 refs.

  1. ADVANCED CUTTINGS TRANSPORT STUDY

    Energy Technology Data Exchange (ETDEWEB)

    Troy Reed; Stefan Miska; Nicholas Takach; Kaveh Ashenayi; Mark Pickell; Len Volk; Mike Volk; Evren Ozbayoglu; Lei Zhou

    2002-07-30

    This is the fourth quarterly progress report for Year-3 of the ACTS Project. It includes a review of progress made in: (1) Flow Loop construction and development and (2) research tasks during the period of time between April 1, 2002 and June 30, 2002. This report presents a review of progress on the following specific tasks: (a) Design and development of an Advanced Cuttings Transport Facility (Task 3: Addition of a Cuttings Injection/Separation System), (b) Research project (Task 6): ''Study of Cuttings Transport with Foam Under LPAT Conditions (Joint Project with TUDRP)''; (c) Research project (Task 9b): ''Study of Foam Flow Behavior Under EPET Conditions''; (d) Research project (Task 10): ''Study of Cuttings Transport with Aerated Mud Under Elevated Pressure and Temperature Conditions''; (e) Research on three instrumentation tasks to measure: Cuttings concentration and distribution in a flowing slurry (Task 11), Foam texture while transporting cuttings. (Task 12), and Viscosity of Foam under EPET (Task 9b); (f) Development of a Safety program for the ACTS Flow Loop. Progress on a comprehensive safety review of all flow-loop components and operational procedures. (Task 1S); (g) Activities towards technology transfer and developing contacts with Petroleum and service company members, and increasing the number of JIP members.

  2. Andean region study

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-10-01

    New opportunities for climate change mitigation arising from a higher energy integration among Andean Pact nations were analysed within the framework of the UNEP/GEF Project. Apart from the search for regional mitigation actions, the study was mainly aimed at detecting methodological problems which arise when passing from a strictly national view to the co-ordination of regional actions to deal with climate change. In accordance with the available resources and data, and in view of the mainly methodological nature of the project, it was decided to analyse the opportunities to delve into the energy integration of the Region as regards electricity and natural gas industries and their eventual impact on the emission of greenhouse gases. Although possibilities of setting up electricity and natural gas markets are real, their impacts on GHG emission from the energy system would not prove substantially higher than those which the nations could achieve through the use of their own energy resources, in view that the Andean systems are competitive rather than complementary. More in-depth studies and detail information will be required - unavailable for the present study - to be able to properly evaluate all benefits associated with higher energy integration. Nevertheless, the supply of natural gas to Ecuador seems to be the alternative with the highest impact on GHG emission. If we were to analyse the supply and final consumption of energy jointly, we would most certainly detect additional mitigation options resulting from higher co-operation and co-ordination in the energy field. (EHS)

  3. Contemplative Media Studies

    Directory of Open Access Journals (Sweden)

    Kevin Healey

    2015-08-01

    Full Text Available The psychological and socio-economic implications of digital technologies call for scholarship that engages questions about the nature of human consciousness, the construction of the self and the ethics of technical development. In this article, I outline a framework for an approach called contemplative media studies. This approach incorporates several different scholarly threads, namely: via critical political-economic media scholarship, a focus on achieving social and economic justice through policy initiatives and structural reform; via media and religious scholarship, an interest in the religious dimensions of digital culture and the role of media in shaping religious identity; and via contemplative studies, an appreciation of the applicability of contemplative principles to research methods and theory. This framework allows us to examine the spiritual ideology that drives the construction of commercial digital platforms and to ask whether alternative platforms might better catalyze human development. Anchored in a critical commitment to socio-economic justice, contemplative media studies is aimed at articulating an ethically-responsive and economically-sustainable architecture of human flourishing.

  4. 1970 British Cohort Study

    Directory of Open Access Journals (Sweden)

    Matt Brown

    2014-10-01

    Full Text Available The 1970 British Cohort Study (BCS70 is one of Britain’s world famous national longitudinal birth cohort studies, three of which are run by the Centre for Longitudinal Studies at the Institute of Education, University of London.  BCS70 follows the lives of more than 17,000 people born in England, Scotland and Wales in a single week of 1970. Over the course of cohort members lives, the BCS70 has collected information on health, physical, educational and social development, and economic circumstances among other factors. Since the birth survey in 1970, there have been nine ‘sweeps’ of all cohort members at ages 5, 10, 16, 26, 30, 34, 38 and most recently at 42. Data has been collected from a number of different sources (the midwife present at birth, parents of the cohort members, head and class teachers, school health service personnel and the cohort members themselves. The data has been collected in a variety of ways including via paper and electronic questionnaires, clinical records, medical examinations, physical measurements, tests of ability, educational assessments and diaries. The majority of BCS70 survey data can be accessed by bona fide researchers through the UK Data Service at the University of Essex.

  5. Ketoprofen Dental Pain Study.

    Science.gov (United States)

    Levin, L M; Cooper, S A; Betts, N J; Wedell, D; Hermann, D G; Lamp, C; Secreto, S A; Hersh, E V

    1997-01-01

    Ketoprofen is a nonsteroidal antiinflammatory drug, recently approved as an over-the-counter (OTC) analgesic at a 12.5 mg dosage strength. This is the first published study which explores the analgesic efficacy and safety of ketoprofen 12.5 mg in patients experiencing pain following the removal of impacted third molars. This study was single-dose, double-blind and randomized utilizing a 6-hour in-patient evaluation period. Patients ingested a single dose of ketoprofen 12.5 mg (n = 30), ketoprofen 37.5 mg (n = 32) or placebo (n = 15) when their post-surgical pain reached at least a moderate intensity on a 5-point categorical (CAT) scale and greater than 50 mm on a 100 mm visual analog scale (VAS). Measures of pain intensity and relief were gathered every 20 minutes for the first 2 hours, and then hourly from hours 3 through 6. Adverse drug reactions were also recorded as they occurred. Both dosages of ketoprofen were significantly more efficacious than placebo (two way ANOVAs, p measures (SPID(VAS), SPID(CAT), TOTPAR) than placebo, with the exception of the 6-hr SPID(CAT) measure for ketoprofen 12.5 mg. No serious side effects were observed in this study. We conclude that ketoprofen in a dose range of 12.5 mg to 37.5 mg is a safe and effective analgesic for the relief of post-operative dental pain.

  6. Cerebrovascular disease

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    2008482 Risk factors for ischemic lacunar stroke associated headache. HU Wei(胡伟), et al. Dept Neurol, Nanjing General Hosp, Nanjing Milit Command, Nanjing 210002. Chin J Nerv Ment Dis 2008;34(5):262-265. Objective To analyze risk factors of stroke-associated headache (SH) and explore its underlying mechanisms. Methods First-ever lacunar infarction patients (n=371) were extracted from Nanjing Stroke Registration Program.

  7. Quantitative Analysis of Bone Microstructure Using Tomosynthesis

    Science.gov (United States)

    2013-10-01

    Parkinson, I. H. (1996). “ Fractal dimension and architecture of trabecular bone.” J Pathol 178(1): 100-105. Flynn, M. J., McGee, R. and Blechinger, J...microstructure ( fractal dimension, lacunarity, mean intercept length and line fraction deviation) to those derived from microCT (distribution properties...cadavers. Methods of fractal , lacunarity, mean intercept length and line fraction deviation analyses are used to quantify cancellous microstructure

  8. STUDI ISLAM PENDEKATAN HERMENEUTIK

    Directory of Open Access Journals (Sweden)

    Elok Noor Farida

    2013-09-01

    Full Text Available ISLAMIC STUDIES USING HERMENEUTICS APPRO- ACH. Al-Qur’an as the Islam’s holy book is a miracle that has been revealed to the Prophet Muhammad as a guide for muslim’s life. As a Muslim, we necessarily have to understand exactly what the message of  the Quran. Al-Qur’an is not only readable even it is a worship, but more than that, how to implement the contents of  the Qur’an in everyday life. In understanding asbab al-nuzul certainly should understand that there are verses in the Qur’an. In addition, it should also understand various methods to understand the Qur’an, one of them is the hermeneutic approach. Hermeneutics as a method of reading the text has been widely recognized in various fields of  traditional Islamic scholarship, especially in the tradition of  fiqh and tafsir al-Qur’an. Meanwhile, modern hermeneutics in Islamic thought can basically be called a great leap in the formulation of  the methodology of  Islamic thought in general and methods of  interpretation of  the Kor’an in particular.Therefore, the approach of  hermeneutics in Islamic studies also need to be studied to add to the treasures of  knowledge and can provide new insights on how to understand the text and interpretation of the text that will be studied. keywords: Islamic Studies, Hermeneutics. Kitab Suci Al-Qur’an sebagai kitab suci agama Islam merupakan mukjizat yang telah diturunkan kepada Nabi Muhammad saw. sebagai pedoman umat Islam sepanjang hayat. Sebagai Muslim yang mempedomani tentu harus memahami betul apa pesan-pesan dalam Al-Qur’an.  Al-Qur’an  tidak  hanya  dibaca  meskipun  bernilai ibadah, akan tetapi lebih dari itu, bagaimana mengimplementasikan isi kandungan Al-Qur’an dalam kehidupan sehari-hari. Dalam memahami tentu harus memahami asbabun nuzul ayat-ayat yang terdapat dalam Al-Qur’an. Di samping itu, juga harus memahami berbagai macam metode dalam memahami Al-Qur’an, di antaranya dengan pendekatan

  9. Environmental study of firefighters.

    Science.gov (United States)

    Jankovic, J; Jones, W; Burkhart, J; Noonan, G

    1991-12-01

    A study of firefighter exposures was undertaken at the request of the U.S. Fire Administration. This work was part of a larger study which included field evaluation of the performance of the self-contained breathing apparatus (SCBA) worn by firefighters during structural firefighting. Measurements were made for a variety of contaminants including CO, CO2, benzene, HCN, HCl, H2SO4, HF, acrolein, CH4, formaldehyde and PNAs. Many of the analyses were performed by collection of bag samples followed by Fourier transform infrared spectroscopy using a field mobile spectrometer. Measurements were also made using solid sorbent tubes and direct-reading meters. Sampling was done both during the knockdown and during overhaul phases of structural firefighting. Also, in order to estimate exposures including those when the SCBAs were worn, measurements were made both inside and outside the SCBA facepiece. Carbon monoxide was the most common contaminant found during knockdown, and about 10% of the samples were greater than 1500 ppm. Formaldehyde, acrolein, hydrogen chloride, hydrogen cyanide, sulphuric acid and hydrogen fluoride all exceeded their respective short-term exposure limits (STEL) on some occasions. Approximately 50% of the knockdown samples for acrolein exceeded the STEL. During overhaul, when masks were usually not worn, many of the contaminants found during knockdown were detected, but typically at much lower concentrations. Inside-mask sampling data suggest that exposure to low concentrations of a variety of compounds is occurring but this is believed to be principally the result of early mask removal or of non-use during knockdown rather than of leakage. The three basic sampling approaches (bag sampling, sorbent tubes and direct-reading meters) proved in this study to be complementary and served to maximize our ability to detect and quantify a wide range of combustion products.

  10. Portable treatment systems study

    Energy Technology Data Exchange (ETDEWEB)

    Sherick, M.J.; Schwinkendorf, W.E.; Bechtold, T.E.; Cole, L.T.

    1997-03-01

    In developing their Site Treatment Plans (STPs), many of the Department of Energy installations identified some form of portable treatment, to facilitate compliant disposition of select mixed low-level wastestreams. The Environmental Management Office of Science and Technology requested that a systems study be performed to better define the potential role of portable treatment with respect to mixed low-level waste, highlight obstacles to implementation, and identify opportunities for future research and development emphasis. The study was performed by first establishing a representative set of mixed waste, then formulating portable treatment system concepts to meet the required processing needs for these wastes. The portable systems that were conceptualized were evaluated and compared to a fixed centralized treatment alternative. The system evaluations include a life-cycle cost analysis and an assessment of regulatory, institutional, and technical issues associated with the potential use of portable systems. The results of this study show that when all costs are included, there are no significant cost differences between portable systems and fixed systems. However, it is also emphasized that many uncertainties exist that could impact the cost of implementing portable treatment systems. Portable treatment could be made more attractive through private sector implementation, although there is little economic incentive for a commercial vendor to develop small, specialized treatment capabilities with limited applicability. Alternatively, there may also be valid reasons why fixed units cannot be used for some problematic wastestreams. In any event, there are some site-specific problems that still need to be addressed, and there may be some opportunity for research and development to make a positive impact in these areas.

  11. Platform evolution studies

    Science.gov (United States)

    Walton, Barbara A.

    1990-01-01

    The polar orbiting platform (POP), being developed by the Work Package 3 (WP3) Project at the Goddard Space Flight Center, will play a key role in the NASA Leadership Initiative, Mission to Planet Earth (MPE). It becomes, with the addition of payloads, an Earth observation satellite observatory. Mission to Planet Earth also has geostationary platforms (GEOP) as part of its global observational system. A study was begun in March 1988 to assess the applicability of the POP orbital replacement units (ORUs) for a geostationary Earth observing mission. Two test cases, representative of MPE payloads, were studied. Case A was used to emphasize the GEOP configuration and design; it used a Titan/Centaur to achieve orbit. Case B, considered to be much further in the future, included some assembly at the Space Station Freedom manned base and use of an orbital transfer vehicle to achieve orbit; requirements on the manned base to support such a mission were emphasized. The study found the POP systems more than adequate to meet GEOP requirements. Two types of changes were required for the POP ORUs: (1) modification to use only one surface for heat rejection; for the battery ORU, this meant 'opening up' the ORU to retain the radiator area with a corresponding decrease in depth; and (2) deletion of equipment not needed. The Case A configuration was shown to be within the planned capability of the Titan IV/Centaur. Assembly requirements were included for the Case B configuration, which is driven by the large microwave antennas of two of the payloads. The final review was April 19, 1989.

  12. Study of Consciousness

    Directory of Open Access Journals (Sweden)

    Samuel Lee

    2011-01-01

    Full Text Available The human brain is a powerful organ that controls most of the body. Researchers around the world have long tried to uncover how the brain operates, how memories are formed and stored. Our understanding of neurological diseases such as Alzheimer's and Parkinson's disease has been rapidly improving, yet much remains to be done. In this work, we attempt to study changes in intracranial pressure (ICP for a 12-hour period and discuss whether the resulting estimates could be used as a measure of consciousness.

  13. Studying Social Movements

    DEFF Research Database (Denmark)

    Uldam, Julie; McCurdy, Patrick

    2013-01-01

    The research method of participant observation has long been used by scholars interested in the motivations, dynamics, tactics and strategies of social movements from a movement perspective. Despite participant observation being a common research method, there have been very few efforts to bring...... and then draws specific links to how the method has been used in the study of activism and social movements. In doing so, this article brings together key academic debates on participant observation, which have been considered separately, such as insider/outsider and overt/covert, but not previously been brought...

  14. Studying bacterial multispecies biofilms

    DEFF Research Database (Denmark)

    Røder, Henriette Lyng; Sørensen, Søren Johannes; Burmølle, Mette

    2016-01-01

    and drawbacks of varying the degree of complexity. This review aims to facilitate multispecies biofilm research in order to expand the current limited knowledge on interspecies interactions. Recent technological advances have enabled total diversity analysis of highly complex and diverse microbial communities...... at the microscale of complex communities, including biofilms.Studies of multispecies biofilms and the interactions shaping these are conducted in traditional approaches used for single-species biofilms with some adjustments; but a crucial point for consideration is which strains to combine and where these should...

  15. Roundabouts Canada case study

    Energy Technology Data Exchange (ETDEWEB)

    Jamieson, M. [Ryerson Polytechnic Univ., Toronto, ON (Canada); Lenters, M. [Roundabouts Canada, Whitby, ON (Canada)

    2002-07-01

    A modern roundabout was constructed in the community of Ancaster, Ontario in response to growing complaints regarding speeding along the major roadway, and queuing on the minor roadway. The roundabout opened on October 25, 2002. The before and after speeds at the roundabout are being studied, and the fastest path characteristics are assessed in an effort to determine whether the predicted fastest path data correlates with the in-service operating speeds. The speed at R1, R2 and R3 locations on the east west, and north south approaches are measured. tabs., figs.

  16. Diffraction studies with ALICE

    CERN Document Server

    Zamora, Pedro González

    2013-01-01

    The measurement of Single and Double Di raction cross-sections in pp collisions by the ALICE Collaboration at p s = 0.9, 2.76 and 7 TeV will be presented. The relevance of di raction to the understanding of inelastic pp interactions will be discussed and the measurement of the inelastic pp cross-section will be presented. A brief status of ALICE’s studies of centrally produced systems, selected with a two-pseudorapidity gap topology, will also be given

  17. Nogales flood detention study

    Science.gov (United States)

    Norman, Laura M.; Levick, Lainie; Guertin, D. Phillip; Callegary, James; Guadarrama, Jesus Quintanar; Anaya, Claudia Zulema Gil; Prichard, Andrea; Gray, Floyd; Castellanos, Edgar; Tepezano, Edgar; Huth, Hans; Vandervoet, Prescott; Rodriguez, Saul; Nunez, Jose; Atwood, Donald; Granillo, Gilberto Patricio Olivero; Ceballos, Francisco Octavio Gastellum

    2010-01-01

    Flooding in Ambos Nogales often exceeds the capacity of the channel and adjacent land areas, endangering many people. The Nogales Wash is being studied to prevent future flood disasters and detention features are being installed in tributaries of the wash. This paper describes the application of the KINEROS2 model and efforts to understand the capacity of these detention features under various flood and urbanization scenarios. Results depict a reduction in peak flow for the 10-year, 1-hour event based on current land use in tributaries with detention features. However, model results also demonstrate that larger storm events and increasing urbanization will put a strain on the features and limit their effectiveness.

  18. The function genomics study

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    @@ Genomics is a biology term appeared ten years ago, used to describe the researches of genomic mapping, sequencing, and structure analysis, etc. Genomics, the first journal for publishing papers on genomics research was born in 1986. In the past decade, the concept of genomics has been widely accepted by scientists who are engaging in biology research. Meanwhile, the research scope of genomics has been extended continuously, from simple gene mapping and sequencing to function genomics study. To reflect the change, genomics is divided into two parts now, the structure genomics and the function genomics.

  19. A longitudinal study

    OpenAIRE

    Hantel, Hajo

    2010-01-01

    This study was conducted to evaluate the influence of stress, coping and occlusion in the development of temporomandibular disorders (TMD). 99 dental students (m/w = 33/66) could be observed over a period of 24 months. Clinical data were recorded using the protocol of RDC/TMD-axis I, Helkimo’s clinical Dysfunction Index (DI) as well as Helkimo’s Index for Occlusal State (OI). For quantitative evaluation the findings of RDC/TMD were transferred into the RDC-Index (Kanzlivius). Data regardin...

  20. Toxicological study of NTO

    Energy Technology Data Exchange (ETDEWEB)

    London, J.E.; Smith, D.M.

    1985-09-01

    The acute oral LD/sub 50/ values for NTO for mice and rats are greater than 5 g/kg. According to classical guidelines, the test material would be considered only slightly toxic or practically non-toxic in both species. Skin application studies in the rabbit with NTO demonstrated that it was mildly irritating cutaneously. With the scoring scheme, the rabbit eye test was considered negative; however, transient conjunctival and corneal irritation did result from the NTO application in several animals and one developed a chronic anterior uveitis. The material did not induce sensitization in the intradermal guinea pig assay. 6 refs., 1 tab.

  1. Bypass Flow Study

    Energy Technology Data Exchange (ETDEWEB)

    Richard Schultz

    2011-09-01

    The purpose of the fluid dynamics experiments in the MIR (Matched Index of-Refraction) flow system at Idaho National Laboratory (INL) is to develop benchmark databases for the assessment of Computational Fluid Dynamics (CFD) solutions of the momentum equations, scalar mixing, and turbulence models for the flow ratios between coolant channels and bypass gaps in the interstitial regions of typical prismatic standard fuel element (SFE) or upper reflector block geometries of typical Modular High-temperature Gas-cooled Reactors (MHTGR) in the limiting case of negligible buoyancy and constant fluid properties. The experiments use Particle Image Velocimetry (PIV) to measure the velocity fields that will populate the bypass flow study database.

  2. Epidemiological studies on syncope

    DEFF Research Database (Denmark)

    Ruwald, Martin Huth

    2013-01-01

    : 1) the use, validity and accuracy of the ICD-10 diagnosis of syncope R55.9 in the National Patient Registry for the use of this diagnosis in the epidemiology of syncope, 2) diagnostics used and etiology of a random selection of patients who had a discharge diagnosis of R55.9, 3) the incidence...... thesis demonstrated that the ICD-10 discharge diagnosis could reliably identify a cohort of patients admitted for syncope and that the discharge code carried a high number of unexplained cases despite use of numerous tests. The last studies showed that syncope is a common cause for hospital contact...

  3. Botswana country study

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Peter [EECG Consultants, Gaborone (Botswana)

    1998-10-01

    The project analysed the baseline economic, energy development and greenhouse gas (GHG) scenarios, and abatement costing of plausible greenhouse gas mitigation options in the energy sector of Botswana. The analysis period for both the baseline and mitigation scenarios is up to 2030 with the short term stretching from 1994 to 2005 and the long term up to 2030. There is a relatively significant potential to reduce GHG emissions in the energy system of Botswana by applying a number of mitigation options. The potential in by applying a set of 21 mitigation options analysed in this study was found to be about 28.7% in 2005 and 26.1% in 2030. (EG)

  4. Mars Rover RTG Study

    Energy Technology Data Exchange (ETDEWEB)

    Schock, Alfred

    1989-08-25

    This report summarizes the results of a Radioisotope Thermoelectric Generator (RTG) design study conducted by Fairchild Space Company at the direction of the U.S. Department of Energy's Office of SpecialApplications, in suppport of the Mars Rover and Sample Return mission under investigation at NASA's Jet Propulsion Laboratory. The report is a rearranged, updated, and significantly expanded amalgam of three interrelated papers presented at the 24th Intersocity Energy Conversion Engineering Conference (IECEC) at Arlington, Virginia, on August 10, 1989.

  5. Environmental pollution studies

    CERN Document Server

    Best, Gerry

    1999-01-01

    This book examines a number of important contemporary environmental issues in an informative and easy-to-read style. The topics covered include sewage treatment, eutrophication, air pollution, acid rain, global warming and pollution from farming. A particularly valuable section of the book describes a range of tests that can be carried out on various environmental parameters. The procedures require relatively simple equipment and they have been pre-tested in a school laboratory. "Environmental Pollution Studies" will be of value to senior school pupils and students at college or university embarking on courses in environmental science.

  6. STUDYING COMPLEX ADAPTIVE SYSTEMS

    Institute of Scientific and Technical Information of China (English)

    John H. Holland

    2006-01-01

    Complex adaptive systems (cas) - systems that involve many components that adapt or learn as they interact - are at the heart of important contemporary problems. The study of cas poses unique challenges: Some of our most powerful mathematical tools, particularly methods involving fixed points, attractors, and the like, are of limited help in understanding the development of cas. This paper suggests ways to modify research methods and tools, with an emphasis on the role of computer-based models, to increase our understanding of cas.

  7. Studies on Infectious Mononucleosis

    Science.gov (United States)

    Joncas, J.; Chagnon, A.; Pavilanis, V.

    1966-01-01

    Viral studies were carried out on throat swabs, rectal swabs and washed white blood cells from 27 cases of infectious mononucleosis (positive Paul-Bunnell-David-sohn test), and from 22 controls. Four cytopathic agents were isolated in the test group, two of which were readily subcultured for at least three successive passages. Three cytopathic agents were recovered in the control group, two of which have been identified as adenovirus type 5 and adenovirus type 3. The unidentified agents tested so far are sensitive to ether and to pH 3. The results of acridine-orange staining and the immunofluorescence technique, using a conjugated control serum and two conjugated convalescent infectious mononucleosis sera, indicate that the isolated agent or agents in the test group are RNA-type agents with a cytoplasmic cycle of development. The overall results of this study lead the authors to suspect a respiratory syncytial-like myxovirus as the as yet unidentified agent which they recovered. ImagesFig. 1aFig. 1bFig. 1cFig. 1dFig. 2aFig. 2bFig. 2cFig. 2dFig. 3aFig. 3bFig. 3cFig. 3dFig. 3eFig. 3f PMID:4952899

  8. Geologic environmental study

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Chun Soo; Bae, Dae Seok; Kim, Kyung Su; Park, Byung Yoon; Koh, Young Kown; Chun, Kwan Sik; Kim, Jhin Wung

    2000-05-01

    The geoscience research works are focused on the production of geologic basic data accompanying with the technical development of geology and hydrogeologic characterization. The lithology of the Korean peninsula consists of a complex structure of 29 rock types from Archean to Quaternary. The wide distribution of Mesozoic plutonic rock is an important consideration as a potential host rock allowing flexibility of siting. The recent tectonic activities are limited to localized particular area, which can be avoided by excluding in the early stage of siting. Three rock types such as plutonic rocks, crystalline gneisses and massive volcanic rocks were suggested as the preferred host rocks for the further study on HLW disposal system. This report contains grouping of regional faults, and on the distributional characteristics of faults and fractures(zones) in terms of lithological domain and tectonical provinces. The regional groundwater regime can be grouped into 3 regimes by tectonic setting and four groundwater regions based on an altitute. Groundwaters can be grouped by their chemistry and host rocks. The origin of groundwater was proposed by isotope ({sup 1}8O, {sup 2}H, {sup 1}3C, {sup 3}4S, {sup 8}7Sr, {sup 1}5N) studies and the residence time of groundwater was inferred from their tritium contents. Based on the geochemical and isotope characteristics, the geochemical evolutions of each types of groundwater were simulated using SOLVEQ/CHILLER and PHREEQC programs.

  9. National transmission grid study

    Energy Technology Data Exchange (ETDEWEB)

    Abraham, Spencer [USDOE Office of the Secretary of Energy, Washington, DC (United States)

    2003-05-31

    The National Energy Policy Plan directed the U.S. Department of Energy (DOE) to conduct a study to examine the benefits of establishing a national electricity transmission grid and to identify transmission bottlenecks and measures to address them. DOE began by conducting an independent analysis of U.S. electricity markets and identifying transmission system bottlenecks using DOE’s Policy Office Electricity Modeling System (POEMS). DOE’s analysis, presented in Section 2, confirms the central role of the nation’s transmission system in lowering costs to consumers through increased trade. More importantly, DOE’s analysis also confirms the results of previous studies, which show that transmission bottlenecks and related transmission system market practices are adding hundreds of millions of dollars to consumers’ electricity bills each year. A more detailed technical overview of the use of POEMS is provided in Appendix A. DOE led an extensive, open, public input process and heard a wide range of comments and recommendations that have all been considered.1 More than 150 participants registered for three public workshops held in Detroit, MI (September 24, 2001); Atlanta, GA (September 26, 2001); and Phoenix, AZ (September 28, 2001).

  10. A Cross - Sectional Study

    Directory of Open Access Journals (Sweden)

    Afsoon Fazlinezhad

    2013-05-01

    Full Text Available   Introduction: Aortic valve sclerosisis considered as a manifestation of coronary atherosclerosis. Recent studies demonstrated an association between aortic valve sclerosis and obstructive coronary artery disease. The purpose of this study was to evaluatethe correlation betweenaortic valve sclerosis andobstructive coronary artery disease and the extent of coronary artery disease in patients hospitalized for chest pain.   Materials and Methods: A total of 230 consecutive patients were referred to the coronary angiography of GhaemMedical Center and were subjected to transthorasic echocardiography for screening of aortic valve sclerosis and coronary risk assessment. The diagnostic value of obstructive coronary artery disease for aortic valve sclerosis was calculated. Results: The patients with obstructive coronary artery disease had a higher prevalence of aortic valve sclerosis compared to those with no coronary artery disease (P< 0.05. Aortic valve sclerosis was an independent predictor for obstructive coronary artery disease by multivariate analysis (P< 0.05. Aortic valve sclerosis had sensitivity of 47% and specificity of 79% and positive predictor value of 92%. Conclusions: Aortic valve sclerosis was an independent predictor for obstructive coronary artery disease in patients with chest pain and was strongly interrelated with the extent of coronary artery disease in these patients.

  11. Retrieval options study

    Energy Technology Data Exchange (ETDEWEB)

    1980-03-01

    This Retrieval Options Study is part of the systems analysis activities of the Office of Nuclear Waste Isolation to develop the scientific and technological bases for radioactive waste repositories in various geologic media. The study considers two waste forms, high level waste and spent fuel, and defines various classes of waste retrieval and recovery. A methodology and data base are developed which allow the relative evaluation of retrieval and recovery costs and the following technical criteria: safety; technical feasibility; ease of retrieval; probable intact retrieval time; safeguards; monitoring; criticality; and licensability. A total of 505 repository options are defined and the cost and technical criteria evaluated utilizing a combination of facts and engineering judgments. The repositories evaluated are selected combinations of the following parameters: Geologic Media (salt, granite, basalt, shale); Retrieval Time after Emplacement (5 and 25 years); Emplacement Design (nominal hole, large hole, carbon steel canister, corrosion resistant canister, backfill in hole, nominal sleeves, thick wall sleeves); Emplacement Configuration (single vertical, multiple vertical, single horizontal, multiple horizontal, vaults; Thermal Considerations; (normal design, reduced density, once-through ventilation, recirculated ventilation); Room Backfill; (none, run-of-mine, early, 5 year delay, 25 year delay, decommissioned); and Rate of Retrieval; (same as emplacement, variably slower depending on repository/canister condition).

  12. ADVANCED CUTTINGS TRANSPORT STUDY

    Energy Technology Data Exchange (ETDEWEB)

    Troy Reed; Stefan Miska; Nicholas Takach; Kaveh Ashenayi; Mark Pickell; Len Volk; Mike Volk; Lei Zhou; Zhu Chen; Crystal Redden; Aimee Washington

    2003-01-30

    This is the second quarterly progress report for Year-4 of the ACTS Project. It includes a review of progress made in: (1) Flow Loop construction and development and (2) research tasks during the period of time between October 1, 2002 and December 30, 2002. This report presents a review of progress on the following specific tasks. (a) Design and development of an Advanced Cuttings Transport Facility Task 3: Addition of a Cuttings Injection/Separation System, Task 4: Addition of a Pipe Rotation System. (b) New research project (Task 9b): ''Development of a Foam Generator/Viscometer for Elevated Pressure and Elevated Temperature (EPET) Conditions''. (d) Research project (Task 10): ''Study of Cuttings Transport with Aerated Mud Under Elevated Pressure and Temperature Conditions''. (e) Research on three instrumentation tasks to measure: Cuttings concentration and distribution in a flowing slurry (Task 11), Foam texture while transporting cuttings. (Task 12), and Viscosity of Foam under EPET (Task 9b). (f) New Research project (Task 13): ''Study of Cuttings Transport with Foam under Elevated Pressure and Temperature Conditions''. (g) Development of a Safety program for the ACTS Flow Loop. Progress on a comprehensive safety review of all flow-loop components and operational procedures. (Task 1S). (h) Activities towards technology transfer and developing contacts with Petroleum and service company members, and increasing the number of JIP members.

  13. Finemet cavity impedance studies

    CERN Document Server

    Persichelli, S; Migliorati, M; Salvant, B

    2013-01-01

    The aim of the study is to evaluate the impedance of the Finemet kicker cavity to be installed in the PS straight section 02 during LS1, under realistic assumptions of bunch length. Time domain simulations with CST Particle Studio have been performed in order to get the impedance of the cavity and make a comparison with the longitudinal impedance measured for a single cell prototype. The study has been performed on simplified 3D geometries imported from a mechanical CATIA drawing, assuming that the simplications have small impact on the nal results. Simulations confirmed that the longitudinal impedance observed with measurements can be excited by bunches circulating in the PS. In the six-cells Finemet cavity, PS bunches circulating in the center can excite a longitudinal impedance, the real part of which has a maximum of 2 kOhm at 4 MHz. This mode does not seem to have any transverse component. All the eigenmodes of the cavity are strongly damped by the Finemet rings: we predict to have no issues regarding tr...

  14. Arrival Metering Precision Study

    Science.gov (United States)

    Prevot, Thomas; Mercer, Joey; Homola, Jeffrey; Hunt, Sarah; Gomez, Ashley; Bienert, Nancy; Omar, Faisal; Kraut, Joshua; Brasil, Connie; Wu, Minghong, G.

    2015-01-01

    This paper describes the background, method and results of the Arrival Metering Precision Study (AMPS) conducted in the Airspace Operations Laboratory at NASA Ames Research Center in May 2014. The simulation study measured delivery accuracy, flight efficiency, controller workload, and acceptability of time-based metering operations to a meter fix at the terminal area boundary for different resolution levels of metering delay times displayed to the air traffic controllers and different levels of airspeed information made available to the Time-Based Flow Management (TBFM) system computing the delay. The results show that the resolution of the delay countdown timer (DCT) on the controllers display has a significant impact on the delivery accuracy at the meter fix. Using the 10 seconds rounded and 1 minute rounded DCT resolutions resulted in more accurate delivery than 1 minute truncated and were preferred by the controllers. Using the speeds the controllers entered into the fourth line of the data tag to update the delay computation in TBFM in high and low altitude sectors increased air traffic control efficiency and reduced fuel burn for arriving aircraft during time based metering.

  15. Why Study the Sun?

    Indian Academy of Sciences (India)

    Arvind Bhatnagar

    2006-06-01

    In this presentation we briefly describe the Sun through large number of illustrations and pictures of the Sun taken from early times to the present day space missions. The importance of the study of the Sun is emphasized as it is the nearest star which presents unparallelled views of surface details and numerous phenomena. Our Sun offers a unique celestial laboratory where a large variety of phenomena take place, ranging in temporal domain from a few milliseconds to several decades, in spatial domain from a few hundred kilometers to thousands of kilometers, and in the temperature domain from a few thousand degrees to several million degrees. Its mass motion ranges from thousandths to thousands of kilometers per second. Such an object provides us with a unique laboratory to study the state of matter in the Universe. The existing solar ground-based and space missions have already revealed several mysteries of the outer environment of our Sun and much more is going to come in the near future from planned new sophisticated ground-based solar telescopes and Space missions. The new technique of helioseismology has unravelled many secrets of the solar interior and has put the Standard Solar Model (SSM) on firm footing. The long-standing problem of solar neutrinos has been recently sorted out, and even the ‘back side’ view of the Sun can be seen using the technique of holographic helioseismology.

  16. The Participation Decision Study

    Directory of Open Access Journals (Sweden)

    Margaret Y. Ficaj

    2014-02-01

    Full Text Available The 2011 participation decision study involved exploration into the impact of the external education environment on the decision for private school participation in Federal funding, one deliberately declining player in the No Child Left Behind Act of 2001(NCLB choice and competition equation. In the qualitative collective case, three religiously triangulated Michigan private school decision-makers submitted to semi-structured interviews. Analysis of the external environmental factors was through the lens of Gould and Eldredge’s (1977 environmentally oriented theory, punctuated equilibria philosophy of change. Analysis involved layering, direct interpretation, categorical aggregation, and cross-comparison of two external environmental categories identified at literature review (NCLB-content and privatization-dynamic with numerous major and sub-groupings and space for newly emergent material. The category privatization-dynamics emerged as significant influence, as did the major theme trust and the sub-themes motivational intent, competency, consistency, grapevine, creativity or inspiration, restrictions on curriculum, lack of awareness of opportunities available, and fear of failure. The study included five specific recommendations for leaders of change to explain, predict, and improve organizational performance toward greater synchronization in operation of the NCLB choice and competition mechanisms.

  17. Studies in children.

    Science.gov (United States)

    Perera, Frederica P; Edwards, Susan C

    2011-01-01

    This chapter first discusses the urgent need for prevention of childhood diseases that impose a huge and growing burden on families and society. It provides a review of recent research in this area to illustrate both the strengths and limitations of molecular epidemiology in drawing needed links between environmental exposures and illness in children. For illustration, three of the major diseases in children are discussed: asthma, cancer and developmental disorders. All three impose significant difficulties, have increased in recent decades, and are thought to be caused in substantial part by environmental factors, such as toxic exposures due to lifestyle choices (i.e. smoking and diet), pollutants in the workplace, ambient air, water and the food supply. These exogenous exposures can interact with "host" factors, such as genetic susceptibility and nutritional deficits, to cause disease. Molecular epidemiology has provided valuable new insights into the magnitude and diversity of exposures beginning in utero, the unique susceptibility of the young, and the adverse preclinical and clinical effects resulting from the interactions between these factors. However, molecular epidemiology also faces certain constraints and challenges that are specific to studies of the very young, including ethical issues, technical issues due to the limited amount of biological specimens that can be obtained, and communication of results to parents and communities. These challenges are particularly apparent when incorporating the newer epigenetic and "omic" techniques and biomarkers into studies of children's diseases.

  18. Mars Rover RTG Study

    Energy Technology Data Exchange (ETDEWEB)

    Schock, Alfred

    1989-11-27

    This report summarizes the results of a Radioisotope Thermoelectric Generator (RTG) design study conducted by Fairchild Space Company at the direction of the U.S. Department of Energy's Office of Special Applications, in support of the Mars Rover and Sample Return mission under investigation at NASA's Jet Propulsion Laboratory. Presented at the 40th Congress of the IAF, Oct. 7-13, 1989 in Torremolinos, Malaga-Spain. The paper describes the design and analysis of Radioisotope Thermoelectric Generators (RTGs) for powering the Mars Rover vehicle, which is a critical element of the unmanned Mars Rover and Sample Return mission (MRSR). The RTG design study was conducted by Fairchild Space for the U.S. DOE in support of the JPL MRSR Project. The paper briefly describes a reference mission scenario, an illustrative Rover design and activity pattern on Mars, and its power system requirements and environmental constraints, including the RTG cooling requirements during transit to Mars. It summarizes the baseline RTG's mass breakdown, and presents a detailed description of its thermal, thermoelectric, and electrical analysis. The results presented show the RTG performance achievable with current technology, and the performance improvements that would be achievable with various technology developments. It provides a basis for selecting the optimum strategy for meeting the Mars Rover design goals with minimal programmatic risk and cost. Cross Reference CID #7135 dated 10/1989. There is a duplicate copy. This document is not relevant to the OSTI Library. Do not send.

  19. Hydrogen energy systems studies

    Energy Technology Data Exchange (ETDEWEB)

    Ogden, J.M.; Steinbugler, M.; Kreutz, T. [Princeton Univ., NJ (United States). Center for Energy and Environmental Studies

    1998-08-01

    In this progress report (covering the period May 1997--May 1998), the authors summarize results from ongoing technical and economic assessments of hydrogen energy systems. Generally, the goal of their research is to illuminate possible pathways leading from present hydrogen markets and technologies toward wide scale use of hydrogen as an energy carrier, highlighting important technologies for RD and D. Over the past year they worked on three projects. From May 1997--November 1997, the authors completed an assessment of hydrogen as a fuel for fuel cell vehicles, as compared to methanol and gasoline. Two other studies were begun in November 1997 and are scheduled for completion in September 1998. The authors are carrying out an assessment of potential supplies and demands for hydrogen energy in the New York City/New Jersey area. The goal of this study is to provide useful data and suggest possible implementation strategies for the New York City/ New Jersey area, as the Hydrogen Program plans demonstrations of hydrogen vehicles and refueling infrastructure. The authors are assessing the implications of CO{sub 2} sequestration for hydrogen energy systems. The goals of this work are (a) to understand the implications of CO{sub 2} sequestration for hydrogen energy system design; (b) to understand the conditions under which CO{sub 2} sequestration might become economically viable; and (c) to understand design issues for future low-CO{sub 2} emitting hydrogen energy systems based on fossil fuels.

  20. Grain alcohol study: summary

    Energy Technology Data Exchange (ETDEWEB)

    The study has concentrated upon a detailed examination of all considerations involved in the production, use, and marketing of ethyl alcohol (Ethanol) as produced from the fermentation of agricultural grains. Each parameter was examined in the light of current energy markets and trends; new sources and technological, and processes for fermentation, the capability of the agricultural industry to support fermentaton demand; the optimization of value of agricultureal crops; and the efficiencies of combining related industries. Anhydrous (200 proof) ethanol makes an excellent blending component for all present automotive fuels and an excellent octane additive for unleaded fuels in proportions up to 35% without requiring modifications to current engines. There is no difference between ethanol produced by fermentation and ethanol produced synthetically from petroleum. The decision to produce ethanol one way or the other is purely economic. The agricultural industry can support a major expansion in the fermentation industry. The residue (distillers grains) from the fermentation of corn for ethanol is an excellent and economical feed for livestock and poultry. A reliable supply of distillers grains can assist in making the large beef feedlot operations more economically viable. The source materials, fuels, products and by-products of an ethanol plant, beef feedlot, gas biodigester plant, municipal waste recovery plant and a steam generated electrical plant are interrelated and mutually beneficial for energy efficiencies and economic gains when co-located. The study concludes that the establishment of such agricultural-environment industrial energy complexes, would provide a broad range of significant benefits to Indiana.

  1. Grain alcohol study: summary

    Energy Technology Data Exchange (ETDEWEB)

    The study has concentrated upon a detailed examination of all considerations involved in the production, use, and marketing of ethyl alcohol (ethanol) as produced from the fermentation of agricultural grains. Each parameter was examined in the light of current energy markets and trends; new sources and technological, and processes for fermentation, the capability of the agricultural industry to support fermentation demand; the optimizaton of value of agricultural crops; and the efficiencies of combining related industries. Ahydrous (200 proof) ethanol makes an excellent blending component for all present automotive fuels and an excellent octane additive for unleaded fuels in proportions up to 35% without requiring modifications to current engines. There is no difference between ethanol produced by fermentation and ethanol produced synthetically from petroleum. The decision to produce ethanol one way or the other is purely economic. The agricultural industry can support a major expansion in the fermentation industry. The residue (distillers grains) from the fermentation of corn for ethanol is an excellent and economical feed for livestock and poultry. A reliable supply of distillers grain can assist in making the large beef feedlot operations more economically viable. The source materials, fuels, products and by-products of an ethanol plant, beef feedlot, gas biodigester plant, municipal waste recovery plant and a steam generated electrical plant are interrelated and mutually beneficial for energy efficiencies and economic gains when co-located. The study concludes that the establishment of such agricultural- environment industrial energy complexes, would provide a broad range of significant benefits to Indiana.

  2. Micro-imaging of the Mouse Lung via MRI

    Science.gov (United States)

    Wang, Wei

    Quantitative measurement of lung microstructure is of great significance in assessment of pulmonary disease, particularly in the earliest stages. Conventional stereological assessment of ex-vivo fixed tissue specimens under the microscope has a long and successful tradition and is regarded as a gold standard, but the invasive nature limits its applications and the practicality of use in longitudinal studies. The technique for diffusion MRI-based 3He lung morphometry was previously developed and validated for human lungs, and was recently extended to ex-vivo mouse lungs. The technique yields accurate, quantitative information about the microstructure and geometry of acinar airways. In this dissertation, the 3He lung morphometry technique is for the first time successfully implemented for in-vivo studies of mice. It can generate spatially-resolved maps of parameters that reveal the microstructure of mouse lung. Results in healthy mice indicate excellent agreement between in-vivo morphometry via 3He MRI and microscopic morphometry after sacrifice. The implementation and validation of 3He morphometry in healthy mice open up new avenues for application of the technique as a precise, noninvasive, in-vivo biomarker of changes in lung microstructure, within various mouse models of lung disease. We have applied 3He morphometry to the Sendai mouse model of lung disease. Specifically, the Sendai-virus model of chronic obstructive lung disease has demonstrated an innate immune response in mouse airways that exhibits similarities to the chronic airway inflammation in human COPD and asthma, but the effect on distal lung parenchyma had not been investigated. We imaged the time course and regional distribution of mouse lung microstructural changes in vivo after Sendai virus (SeV) infection with 1H and 3He diffusion MRI. 1H MR images detected the SeV-induced pulmonary inflammation in vivo and 3He lung morphometry showed modest increase in alveolar duct radius distal to airway

  3. Muhammadiyah: A Preliminary Study

    Directory of Open Access Journals (Sweden)

    Azyumardi Azra

    2014-03-01

    Full Text Available This article is a collection of Bibliography reviewer that discuss Muhammadiyah. The following are some of the bibliography were reviewed:A.R. Sukrianta dan Abdul Munir Malkhan, Perkembangan Pemikiran Muhammadiyah dari Masa ke Masa: Menyambut Muktamar ke-41, (Yogyakarta: Dua Dimensi, 1985.A.R. Sukriyanto dan Abdul Munir Mulkhan, Pergumulan Pemikiran dalam Muhammadiyah, (Yogyakarta: Sipress, 1990.Ruslan Abdul Gani. et.al., Cita dan Citra Muhammadiyah, (Jakarta: Pustaka Panjimas, 1985.M.T. Arifin, Gagasan Pembaharuan Muhammadiyah, (Jakarta: Pustaka Jaya, 1987.M.T. Arifin, Muhammadiyah: Potret yang Berubah, (Surakarta: Institut Gelanggang Pemikiran Filsafat Sosial Budaya dan Kependidikan, 1990.M. Yusron Asrofie, Kiyai Haji Ahmad Dahlan, Pemikiran dan Kepemimpinannya, (Yogyakarta: Yogyakarta Offset, 1983.Fathurrahman Djamil, Ijtihad Muhammadiyah dalam Masalah-masalah Fiqh Kontemporer, (Jakarta: Doctoral Dissertation the State Institute of Islamic Studies (IAIN, 1994.Yunahar Ilyas. et.al., Muhammadiyah dan NU: Reorientasi Wawasan Keislaman, (Yogyakarta: LPPI UMY, LKPSM NU, & PP al-Muhsin, 1993.Musthafa kamal, Chusnan Yusuf, dan Rosyad Sholeh, Muhammadiyah sebagai Gerakan Islam, (Yogyakarta: Penerbit Persatuan, 1976.M. Rusli Karim, Muhammadiyah dalam Kritik dan Komentar, (Jakarta: Rajawali, 1986.Arbiyah Lubis, Pemikiran Muhammadiyah dan Muhammad Abduh: Suatu Studi Perbandingan, (Jakarta: Doctoral Dissertation the State Institute of Islamic Studies (IAIN, 1989.Abdul Munir Mulkhan, Pemikiran K.H. Ahmad Dahlan dan Muhammadiyah dalam Perspektif Perubahan Sosial, (Jakarta: Bumi Aksara, 1990.Abdul Munir Mulkhan, Pak AR Menjawab 245 Permasalahan dalam Islam, (Yogyakarta: Sipress, 1990.M. Din Syamsuddin, Muhammadiyah Kini dan Esok, (Jakarta: Pustaka Panjimas, 1990.H.S. Prodjokusumo, Melestarikan Muhammadiyah, (Jakarta: Pimpinan Pusat Muhammadiyah, 1985.Yusuf Abdullah Puar, Perjuangan dan Pengabdian Muhammadiyah, (Jakarta: Pustaka Antara, 1989.Sahlan Rosidi

  4. La Jolla Fog Study

    Science.gov (United States)

    Roberts, G. C.; Ramana, M.; Pham, A.; Ramanathan, V.

    2002-12-01

    The Center for Atmospheric Sciences at the Scripps Institution of Oceanography conducted a ground-based experiment to study fog/marine-stratus clouds over the San Diego region during the summer months of 2002. The purpose of the experiment is to understand aerosol/cloud interactions and how they might influence cloud radiative properties and precipitation. We operated several instruments on Mt. Soledad to study aerosol and cloud properties. These instruments include a forward scattering spectrometer probe (FSSP-100) and an aerosol particle sizer (APS) to measure the cloud droplet spectra during fog events, condensation particle counters to determine total aerosol concentrations, cloud condensation nuclei counters to understand aerosol/cloud droplet interactions, a scanning mobility particle sizer (SMPS) to determine dry aerosol number size distributions, and a weather station to relate fog events to local meteorology. Aerosol concentrations showed a diel variation with high and variable particle concentrations during the day, which often were greater than 104 cm-3. Nighttime concentrations were lower (i.e., several thousand cm-3) and exhibited less variation than daytime values. In general, aerosol concentrations do not appear to be correlated to droplet concentrations indicating that local anthropogenic sources may not have a large influence on the coastal fog. Two types of events (haze and fog) have been characterized during this study based on the droplet distribution. A haze event was dominated by droplets less than 5 μm diameter and sometimes exceeded droplet concentrations of 1000 cm-3. There were virtually no particles larger than 5 micron diameter during these events. A fog event was characterized by larger droplets with droplets greater than 5 μm diameter accounting for a bulk of the number concentration. The average effective radius during these fog events was about 5 μm and the droplet concentration rarely exceeded 100 cm-3. On several occasions, a

  5. Expendable launch vehicle studies

    Science.gov (United States)

    Bainum, Peter M.; Reiss, Robert

    1995-01-01

    Analytical support studies of expendable launch vehicles concentrate on the stability of the dynamics during launch especially during or near the region of maximum dynamic pressure. The in-plane dynamic equations of a generic launch vehicle with multiple flexible bending and fuel sloshing modes are developed and linearized. The information from LeRC about the grids, masses, and modes is incorporated into the model. The eigenvalues of the plant are analyzed for several modeling factors: utilizing diagonal mass matrix, uniform beam assumption, inclusion of aerodynamics, and the interaction between the aerodynamics and the flexible bending motion. Preliminary PID, LQR, and LQG control designs with sensor and actuator dynamics for this system and simulations are also conducted. The initial analysis for comparison of PD (proportional-derivative) and full state feedback LQR Linear quadratic regulator) shows that the split weighted LQR controller has better performance than that of the PD. In order to meet both the performance and robustness requirements, the H(sub infinity) robust controller for the expendable launch vehicle is developed. The simulation indicates that both the performance and robustness of the H(sub infinity) controller are better than that for the PID and LQG controllers. The modelling and analysis support studies team has continued development of methodology, using eigensensitivity analysis, to solve three classes of discrete eigenvalue equations. In the first class, the matrix elements are non-linear functions of the eigenvector. All non-linear periodic motion can be cast in this form. Here the eigenvector is comprised of the coefficients of complete basis functions spanning the response space and the eigenvalue is the frequency. The second class of eigenvalue problems studied is the quadratic eigenvalue problem. Solutions for linear viscously damped structures or viscoelastic structures can be reduced to this form. Particular attention is paid to

  6. Cask fleet operations study

    Energy Technology Data Exchange (ETDEWEB)

    1988-01-01

    The Nuclear Waste Policy Act of 1982 assigned to the Department of Energy's (DOE) Office of Civilian Waste Management the responsibility for disposing of high-level waste and spent fuel. A significant part of that responsibility involves transporting nuclear waste materials within the federal waste management system; that is, from the waste generator to the repository. The lead responsibility for transportation operations has been assigned to Oak Ridge Operations, with Oak Ridge National Laboratory (ORNL) providing technical support through the Transportation Operations Support Task Group. One of the ORNL support activities involves assessing what facilities, equipment and services are required to assure that an acceptable, cost-effective and safe transportation operations system can be designed, operated and maintained. This study reviews, surveys and assesses the experience of Nuclear Assurance Corporation (NAC) in operating a fleet of spent-fuel shipping casks to aid in developing the spent-fuel transportation system.

  7. Web Plagiarism: Empirical Study

    Directory of Open Access Journals (Sweden)

    Alexander E. Voiskounsky

    2009-01-01

    Full Text Available A questionnaire measuring web plagiarism (or academic cheating, worked out by Underwood and Szabo (2003 has been adapted and applied to the population of undergraduate science students in Russia. The students at four technical universities are questioned (N=292. The study shows the students perform webplagiarizing, i.e. take materials from the Internet and hand these materials in as their own assignments. Russian students are reportedly competent in the use of the Internet; they report to have rather few moral barriers towards plagiarizing; they believe most of their mates do the same; they are not sure their tutors are able and willing to recognize cheating; finally, they are competent enough in English and are hypothetically able to plagiarize in two languages.

  8. Organization within Organization Studies

    DEFF Research Database (Denmark)

    Lopdrup-Hjorth, Thomas

    This paper explores how prevalent contemporary problematizations of organizations coincide with a widespread assessment that Organization Studies (OS) has run out of steam. This impasse, the paper argues, is largely due to the emergence of an organization-phobia that has come to seize several...... strands of theorizing. By attending to the wide-ranging and far-reaching history of this organization-phobia, the paper argues that OS has become increasingly incapable of speaking about its core object. I show how organizations went from being conceptualized as entities of major importance to becoming...... associated with all kinds of ills. Through this history, organizations as distinct entities have been rendered so problematic that they have gradually come to be removed from the center of OS. The costs of this have been rather significant. Besides undermining the grounds that gave OS intellectual...

  9. Study of Meteoritic Inclusion

    DEFF Research Database (Denmark)

    Olsen, Mia Bjørg Stolberg

    There is no question more fundamental than understanding our origins, in other words, understanding our place in the cosmos. This question is particularly timely, as results in the field of exoplanet research have established with confidence that about half of the stars in the galaxy are orbited...... as astronomical observation of starforming regions and exoplanets provide a framework for understanding star-formation processes and the evolution of planetary systems, but offer no direct insight into the earliest solar system. This necessary and complementary information can be obtained through the study...... of meteorite samples that date back to the birth of the solar system. In this thesis, we have taken advantage of novel methods for the high-precision analysis of various radiogenic and stable isotope systems by plasma source and thermal ionization mass spectrometry (ICPMS and TIMS) as well as by secondary...

  10. Geology orbiter comparison study

    Science.gov (United States)

    Cutts, J. A. J.; Blasius, K. R.; Davis, D. R.; Pang, K. D.; Shreve, D. C.

    1977-01-01

    Instrument requirements of planetary geology orbiters were examined with the objective of determining the feasibility of applying standard instrument designs to a host of terrestrial targets. Within the basic discipline area of geochemistry, gamma-ray, X-ray fluorescence, and atomic spectroscopy remote sensing techniques were considered. Within the discipline area of geophysics, the complementary techniques of gravimetry and radar were studied. Experiments using these techniques were analyzed for comparison at the Moon, Mercury, Mars and the Galilean satellites. On the basis of these comparative assessments, the adaptability of each sensing technique was judged as a basic technique for many targets, as a single instrument applied to many targets, as a single instrument used in different mission modes, and as an instrument capability for nongeoscience objectives.

  11. Chinese Studies and Beyond

    DEFF Research Database (Denmark)

    Brødsgaard, Kjeld Erik

    2013-01-01

    Many different conceptual approaches and models have been used to analyze contemporary Chinese history and politics. Some of the more commonly used include "totalitarianism", "two-line struggle", "clientelism", "tendency analysis", "political culture", "interest group politics", "bureaucratic...... politics", "corporatism", "civil society", "fragmented authoritarianism", etc. (Brødsgaard, 1989; Guo 2013). This paper will survey these approaches in order to place the analysis of the contemporary Chinese politics and history in a comparative perspective. A survey of the field will remind us...... that contemporary China studies have increasingly developed into a collective effort and that no scholar conducts his/her research in a vacuum devoid of dept to other contributions in the field. The paper will focus on the period since the Cultural Revolution. Consequently, we will not attempt a discussion...

  12. Studying the Moon

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The moon,sister sphere to the Earth, has long held the attention of mankind as a source of mystery,inspiration and wonder.Its sway has been chronicled in myth,literature and song.In the final week of October,China embarked on its first attempt to better scientifically understand the moon and its relationship to the Earth by launching the lunar orbiter Chang’e-1.Though named after a deity that Chinese fairy tales say lived in the moon,this new venture to study our closest celestial neighbor is based largely on the reality of technology and scientific advancement.As the most recent phase in China’s decades old aerospace program,the launch showcases both the country’s place on the world stage and its technological and scientific advancements-not only for the benefit of its own people,but for all of mankind.

  13. Polymer Infiltration Studies

    Energy Technology Data Exchange (ETDEWEB)

    Marchello, J.M.

    1993-06-01

    Significant progress has been made on the preparation of carbon fiber composites using advanced polymer resins during the past three months. Current and ongoing research activities reported herein include: (1) Prepregger Hot Sled Operation; (2) Ribbonizing Powder-Impregnated Towpreg; (3) Textile Composites from Powder-Coated Towpreg: Role of Bulk Factor; and (4) Powder Curtain Prepreg Process. During the coming months research will be directed toward further development of the new powder curtain prepregging method and on ways to customize dry powder towpreg for textile and robotic applications in aircraft part fabrication. Studies of multi-tow powder prepregging and ribbon preparation will be conducted in conjunction with continued development of prepegging technology and the various aspects of composite part fabrication using customized towpreg. Also, work will continue on the analysis of the new solution prepegger.

  14. Psychopharmacological Studies in Mice.

    Science.gov (United States)

    Matsuda, Toshio

    2016-01-01

    Since 1998, when the laboratory of Medicinal Pharmacology was established in the Graduate School of Pharmaceutical Sciences, Osaka University, I have been interested in psychopharmacological research topics. During this period, we identified a number of novel regulatory mechanisms that control the prefrontal dopamine system through functional interaction between serotonin1A and dopamine D2 receptors or between serotonin1A and σ1 receptors. Our findings suggest that strategies that enhance the prefrontal dopamine system may have therapeutic potential in the treatment of psychiatric disorders. We also found that environmental factors during development strongly impact the psychological state in adulthood. Furthermore, we clarified the pharmacological profiles of the acetylcholinesterase inhibitors donepezil, galantamine, and rivastigmine, providing novel insights into their mechanisms of action. Finally, we developed the female encounter test, a novel method for evaluating motivation in mice. This simple method should help advance future psychopharmacological research. In this review, we summarize the major findings obtained from our recent studies in mice.

  15. Boundary layer transition studies

    Science.gov (United States)

    Watmuff, Jonathan H.

    1995-02-01

    A small-scale wind tunnel previously used for turbulent boundary layer experiments was modified for two sets of boundary layer transition studies. The first study concerns a laminar separation/turbulent reattachment. The pressure gradient and unit Reynolds number are the same as the fully turbulent flow of Spalart and Watmuff. Without the trip wire, a laminar layer asymptotes to a Falkner & Skan similarity solution in the FPG. Application of the APG causes the layer to separate and a highly turbulent and approximately 2D mean flow reattachment occurs downstream. In an effort to gain some physical insight into the flow processes a small impulsive disturbance was introduced at the C(sub p) minimum. The facility is totally automated and phase-averaged data are measured on a point-by-point basis using unprecedently large grids. The evolution of the disturbance has been tracked all the way into the reattachment region and beyond into the fully turbulent boundary layer. At first, the amplitude decays exponentially with streamwise distance in the APG region, where the layer remains attached, i.e. the layer is viscously stable. After separation, the rate of decay slows, and a point of minimum amplitude is reached where the contours of the wave packet exhibit dispersive characteristics. From this point, exponential growth of the amplitude of the disturbance is observed in the detached shear layer, i.e. the dominant instability mechanism is inviscid. A group of large-scale 3D vortex loops emerges in the vicinity of the reattachment. Remarkably, the second loop retains its identify far downstream in the turbulent boundary layer. The results provide a level of detail usually associated with CFD. Substantial modifications were made to the facility for the second study concerning disturbances generated by Suction Holes for laminar flow Control (LFC). The test section incorporates suction through interchangeable porous test surfaces. Detailed studies have been made using isolated

  16. Binary Popldation Synthcsis Study

    Institute of Scientific and Technical Information of China (English)

    HAN Zhanwen

    2011-01-01

    Binary population synthesis (BPS), an approach to evolving millions of stars (including binaries) simultaneously, plays a crucial role in our understanding of stellar physics, the structure and evolution of galaxies, and cosmology. We proposed and developed a BPS approach, and used it to investigate the formation of many peculiar stars such as hot subdwarf stars, progenitors of type la supernovae, barium stars, CH stars, planetary nebulae, double white dwarfs, blue stragglers, contact binaries, etc. We also established an evolution population synthesis (EPS) model, the Yunnan Model, which takes into account binary interactions for the first time. We applied our model for the origin of hot subdwarf stars in the study of elliptical galaxies and explained their far-UV radiation.

  17. BWID System Design Study

    Energy Technology Data Exchange (ETDEWEB)

    O' Brien, M.C.; Rudin, M.J.; Morrison, J.L.; Richardson, J.G.

    1991-01-01

    The mission of the Buried Waste Integrated Demonstration (BWID) System Design Study is to identify and evaluate technology process options for the cradle-to-grave remediation of Transuranic (TRU)-Contaminated Waste Pits and Trenches buried at the Idaho National Engineering Laboratory (INEL). Emphasis is placed upon evaluating system configuration options and associated functional and operational requirements for retrieving and treating the buried wastes. A Performance-Based Technology Selection Filter was developed to evaluate the identified remediation systems and their enabling technologies based upon system requirements and quantification of technical Comprehensive Environmental Response, Compensation, and Liability (CERCLA) balancing criteria. Remediation systems will also be evaluated with respect to regulatory and institutional acceptance and cost-effectiveness.

  18. BWID System Design Study

    Energy Technology Data Exchange (ETDEWEB)

    O`Brien, M.C.; Rudin, M.J.; Morrison, J.L.; Richardson, J.G.

    1991-12-31

    The mission of the Buried Waste Integrated Demonstration (BWID) System Design Study is to identify and evaluate technology process options for the cradle-to-grave remediation of Transuranic (TRU)-Contaminated Waste Pits and Trenches buried at the Idaho National Engineering Laboratory (INEL). Emphasis is placed upon evaluating system configuration options and associated functional and operational requirements for retrieving and treating the buried wastes. A Performance-Based Technology Selection Filter was developed to evaluate the identified remediation systems and their enabling technologies based upon system requirements and quantification of technical Comprehensive Environmental Response, Compensation, and Liability (CERCLA) balancing criteria. Remediation systems will also be evaluated with respect to regulatory and institutional acceptance and cost-effectiveness.

  19. Studying health in Greenland

    DEFF Research Database (Denmark)

    Bjerregaard, Peter; Mulvad, Gert; Olsen, Jørn

    2003-01-01

    Health research in Greenland has contributed with several findings of interest for the global scientific community and has documented health problems and risk factors of importance for planning the local health care system. The study of how health develops in small, scattered communities during...... to that of the industrialized world, while still including local outbreaks of tuberculosis. Health research in Greenland is logistically difficult and costly, but offers opportunities not found elsewhere in the world. A long tradition of registration enhances the possibilities for research. A number of research institutions...... in Denmark and Greenland have conducted health research in Greenland for many years in cooperation with, among others, researchers in Canada and Alaska. National and international cooperation is supported by the Danish/Greenlandic Society for Circumpolar Health, the International Union for Circumpolar Health...

  20. ADVANCED CUTTINGS TRANSPORT STUDY

    Energy Technology Data Exchange (ETDEWEB)

    Stefan Miska; Troy Reed; Ergun Kuru

    2004-09-30

    The Advanced Cuttings Transport Study (ACTS) was a 5-year JIP project undertaken at the University of Tulsa (TU). The project was sponsored by the U.S. Department of Energy (DOE) and JIP member companies. The objectives of the project were: (1) to develop and construct a new research facility that would allow three-phase (gas, liquid and cuttings) flow experiments under ambient and EPET (elevated pressure and temperature) conditions, and at different angle of inclinations and drill pipe rotation speeds; (2) to conduct experiments and develop a data base for the industry and academia; and (3) to develop mechanistic models for optimization of drilling hydraulics and cuttings transport. This project consisted of research studies, flow loop construction and instrumentation development. Following a one-year period for basic flow loop construction, a proposal was submitted by TU to the DOE for a five-year project that was organized in such a manner as to provide a logical progression of research experiments as well as additions to the basic flow loop. The flow loop additions and improvements included: (1) elevated temperature capability; (2) two-phase (gas and liquid, foam etc.) capability; (3) cuttings injection and removal system; (4) drill pipe rotation system; and (5) drilling section elevation system. In parallel with the flow loop construction, hydraulics and cuttings transport studies were preformed using drilling foams and aerated muds. In addition, hydraulics and rheology of synthetic drilling fluids were investigated. The studies were performed under ambient and EPET conditions. The effects of temperature and pressure on the hydraulics and cuttings transport were investigated. Mechanistic models were developed to predict frictional pressure loss and cuttings transport in horizontal and near-horizontal configurations. Model predictions were compared with the measured data. Predominantly, model predictions show satisfactory agreements with the measured data. As a

  1. Advanced drilling systems study.

    Energy Technology Data Exchange (ETDEWEB)

    Pierce, Kenneth G.; Livesay, Billy Joe; Finger, John Travis (Livesay Consultants, Encintas, CA)

    1996-05-01

    This report documents the results of a study of advanced drilling concepts conducted jointly for the Natural Gas Technology Branch and the Geothermal Division of the U.S. Department of Energy. A number of alternative rock cutting concepts and drilling systems are examined. The systems cover the range from current technology, through ongoing efforts in drilling research, to highly speculative concepts. Cutting mechanisms that induce stress mechanically, hydraulically, and thermally are included. All functions necessary to drill and case a well are considered. Capital and operating costs are estimated and performance requirements, based on comparisons of the costs for alternative systems to conventional drilling technology, are developed. A number of problems common to several alternatives and to current technology are identified and discussed.

  2. Study on Probiotic Icecream

    Directory of Open Access Journals (Sweden)

    Cristina Cota

    2013-11-01

    Full Text Available Use of probiotics in human diet benefits the consumers by regulating intestinal transit and immune system. Using various foods as a vehicle for probiotics has become increasingly popular practice. Based on these considerations, we wanted to study the possibility of obtaining icecream which contains viable microorganism cells with probiotic role. I chose ice cream because it is a product with a high nutrient content both for microorganisms and consumers. The main objective of this paper is to study the ability of different strains of probiotics to remain viable in the matured icecream compared to icecream stored at -5°C. Five samples of icecream were prepared, all after the same recipe. Molasses was used as a sweetener. The difference between the five types of ice cream consisted of the milk used, which was inoculated with different strains: Lactobacillus plantarum, Bifidobacterium infantis 4BN, Lactobacillus casei 4BN, Bifidobacterium breve 4BN and a mix prepared from the strains mentioned above. We determined the fat content of the icecream, using the butirometric method and its acidity by titration with NaOH. The results obtained were compared with the acidity and the fat content (determined using the Röse-Gottlieb extraction method of the homemade icecream. Viable cell counting was performed by Trypane-Blue method and then the Fourier-IR spectra of the samples were evaluated. The cells of Lactobacillus plantarum strain and the bacterial cells in the mix proliferated the best, both in matured icecream and in icecream stored at -5°C. Most of the cells belonging to other strains of bacteria remained viable, but not all. Given these results, we can consider the molasses sweetened icecream as a suitable food product to carry certain types of probiotics.

  3. Nuclear spectroscopic studies

    Energy Technology Data Exchange (ETDEWEB)

    Bingham, C.R.; Guidry, M.W.; Riedinger, L.L.; Sorensen, S.P.

    1993-02-08

    The Nuclear Physics group at the University of Tennessee, Knoxville is involved in several aspects of heavy-ion physics including both nuclear structure and reaction mechanisms. While our main emphasis is on experimental problems involving heavy-ion accelerators, we have maintained a strong collaboration with several theorists in order to best pursue the physics of our measurements. During the last year we have led several experiments at the Holifield Heavy Ion Research Facility and participated in others at Argonne National Laboratory. Also, we continue to be very active in the collaboration to study ultra-relativistic heavy ion physics utilizing the SPS accelerator at CERN in Geneva, Switzerland and in a RHIC detector R D project. Our experimental work is in four broad areas: (1) the structure of nuclei at high angular momentum, (2) heavy-ion induced transfer reactions, (3) the structure of nuclei far from stability, and (4) ultra-relativistic heavy-ion physics. The results of studies in these particular areas will be described in this document in sections IIA, IIB, IIC, and IID, respectively. Areas (1), (3), and (4) concentrate on the structure of nuclear matter in extreme conditions of rotational motion, imbalance of neutrons and protons, or very high temperature and density. Area (2) pursues the transfer of nucleons to states with high angular momentum, both to learn about their structure and to understand the transfer of particles, energy, and angular momentum in collisions between heavy ions. An important component of our program is the strong emphasis on the theoretical aspects of nuclear structure and reactions.

  4. Studies of welded joints

    Directory of Open Access Journals (Sweden)

    J. M. Krupa

    2010-07-01

    Full Text Available Studies of a welded joint were described. The joint was made as a result of the reconstruction of a truss and one of the possible means to make a repair. The studies were of a simulation character and were targeted at the detection of welding defects and imperfections thatshould be eliminated in a real structure. A model was designed and on this model the tests and examinations were carried out. The modelwas made under the same conditions as the conditions adopted for repair. It corresponded to the real object in shape and dimensions, and in the proposed technique of welding and welding parameters. The model was composed of five plates joined together with twelve beads.The destructive and non-destructive tests were carried out; the whole structure and the respective welds were also examined visually. Thedefects and imperfections in welds were detected by surface methods of inspection, penetration tests and magnetic particle flaw detection.The model of the welded joint was prepared by destructive methods, a technique that would never be permitted in the case of a realstructure. For the investigations it was necessary to cut out the specimens from the welded joint in direction transverse to the weld run. The specimens were subjected to metallographic examinations and hardness measurements. Additionally, the joint cross-section was examined by destructive testing methods to enable precise determination of the internal defects and imperfections. The surface methods were applied again, this time to determine the severity of welding defects. The analysis has proved that, fabricated under proper conditions and with parameters of the welding process duly observed, the welded joint has good properties and repairs of this type are possible in practice.

  5. Paraffin Oxidation Studies

    Directory of Open Access Journals (Sweden)

    Mrs. S. J. Purohit

    2013-02-01

    Full Text Available The oxidation of paraffin has been studied with keen interest by several workers from all over the world; as oxidation leads to the introduction of various functional groups in hydrocarbon chains. Processes involving the Oxidation of Paraffin’s in the liquid phase, using air or oxygen are of great importance to industrialized economies because of their role in converting petroleum hydrocarbon feed stocks such as alkanes, olefins and aromatics into industrial organic chemicals important in the polymer, petrochemicals ,cosmetics and detergent industries. The oxidation leads predominantly to the formation of secondary alcohols consisting of a mixture of all possible isomers with the same number of carbon atoms in the molecules as the initial hydrocarbons. The secondary alcohols which are oxidation products of paraffin exhibit excellent hydrolytic, oxidative and color stability, because of the nature of their branching. These alcohols have lower melting points than straight chain alcohols of corresponding length, while retaining their high temperature stability. The oxidation of paraffin wax to fatty acids is carried out in temperature range 110 0C- 140 0C. Paraffin oxidation which is carried out by ALFOL, Oxo-processes, are high temperature, high pressure processes which utilize expensive catalysts, making them energy intensive as well as expensive. The maximum conversion achieved yet by existing processes is 15�0for a batch time of 4 hours. A cheaper alternative in this article has been studied, in which paraffin Oxidation has been carried out in a foam reactor at moderate temperature and pressure with suitable catalyst , the output of the products is increased up to 62%.

  6. Microbial Field Pilot Study

    Energy Technology Data Exchange (ETDEWEB)

    Knapp, R.M.; McInerney, M.J.; Menzie, D.E.; Chisholm, J.L.

    1990-11-01

    This report covers progress made during the first year of the Microbial Field Pilot Study project. Information on reservoir ecology and characterization, facility and treatment design, core experiments, bacterial mobility, and mathematical modeling are addressed. To facilitate an understanding of the ecology of the target reservoir analyses of the fluids which support bacteriological growth and the microbiology of the reservoir were performed. A preliminary design of facilities for the operation of the field pilot test was prepared. In addition, procedures for facilities installation and for injection treatments are described. The Southeast Vassar Vertz Sand Unit (SEVVSU), the site of the proposed field pilot study, is described physically, historically, and geologically. The fields current status is presented and the ongoing reservoir simulation is discussed. Core flood experiments conducted during the last year were used to help define possible mechanisms involved in microbial enhanced oil recovery. Two possible mechanisms, relative permeability effects and changes in the capillary number, are discussed and related to four Berea core experiments' results. The experiments were conducted at reservoir temperature using SEVVSU oil, brine, and bacteria. The movement and activity of bacteria in porous media were investigated by monitoring the growth of bacteria in sandpack cores under no flow conditions. The rate of bacteria advancement through the cores was determined. A mathematical model of the MEOR process has been developed. The model is a three phase, seven species, one dimensional model. Finite difference methods are used for solution. Advection terms in balance equations are represented with a third- order upwind differencing scheme to reduce numerical dispersion and oscillations. The model is applied to a batch fermentation example. 52 refs., 26 figs., 21 tabs.

  7. Hydrogen energy systems studies

    Energy Technology Data Exchange (ETDEWEB)

    Ogden, J.M.; Steinbugler, M.; Dennis, E. [Princeton Univ., NJ (United States)] [and others

    1995-09-01

    For several years, researchers at Princeton University`s Center for Energy and Environmental Studies have carried out technical and economic assessments of hydrogen energy systems. Initially, we focussed on the long term potential of renewable hydrogen. More recently we have explored how a transition to renewable hydrogen might begin. The goal of our current work is to identify promising strategies leading from near term hydrogen markets and technologies toward eventual large scale use of renewable hydrogen as an energy carrier. Our approach has been to assess the entire hydrogen energy system from production through end-use considering technical performance, economics, infrastructure and environmental issues. This work is part of the systems analysis activity of the DOE Hydrogen Program. In this paper we first summarize the results of three tasks which were completed during the past year under NREL Contract No. XR-11265-2: in Task 1, we carried out assessments of near term options for supplying hydrogen transportation fuel from natural gas; in Task 2, we assessed the feasibility of using the existing natural gas system with hydrogen and hydrogen blends; and in Task 3, we carried out a study of PEM fuel cells for residential cogeneration applications, a market which might have less stringent cost requirements than transportation. We then give preliminary results for two other tasks which are ongoing under DOE Contract No. DE-FG04-94AL85803: In Task 1 we are assessing the technical options for low cost small scale production of hydrogen from natural gas, considering (a) steam reforming, (b) partial oxidation and (c) autothermal reforming, and in Task 2 we are assessing potential markets for hydrogen in Southern California.

  8. Thermionic Reactor Design Studies

    Energy Technology Data Exchange (ETDEWEB)

    Schock, Alfred

    1994-06-01

    During the 1960's and early 70's the author performed extensive design studies, analyses, and tests aimed at thermionic reactor concepts that differed significantly from those pursued by other investigators. Those studies, like most others under Atomic Energy Commission (AEC and DOE) and the National Aeronautics and Space Administration (NASA) sponsorship, were terminated in the early 1970's. Some of this work was previously published, but much of it was never made available in the open literature. U.S. interest in thermionic reactors resumed in the early 80's, and was greatly intensified by reports about Soviet ground and flight tests in the late 80's. This recent interest resulted in renewed U.S. thermionic reactor development programs, primarily under Department of Defense (DOD) and Department of Energy (DOE) sponsorship. Since most current investigators have not had an opportunity to study all of the author's previous work, a review of the highlights of that work may be of value to them. The present paper describes some of the author's conceptual designs and their rationale, and the special analytical techniques developed to analyze their performance. The basic designs, first published in 1963, are based on single-cell converters, either double-ended diodes extending over the full height of the reactor core or single-ended diodes extending over half the core height. In that respect they are similar to the thermionic fuel elements employed in the Topaz-2 reactor subsequently developed in the Soviet Union, copies of which were recently imported by the U.S. As in the Topaz-2 case, electrically heated steady-state performance tests of the converters are possible before fueling. Where the author's concepts differed from the later Topaz-2 design was in the relative location of the emitter and the collector. Placing the fueled emitter on the outside of the cylindrical diodes permits much higher axial conductances to reduce ohmic

  9. Snow Radiance Assimilation Studies

    Science.gov (United States)

    Kim, E. J.; Durand, M. T.; Toure, A.; Margulis, S. A.; Goita, K.; Royer, A.; Lu, H.

    2009-12-01

    Passive microwave-based retrievals of terrestrial snow parameters from satellite observations form a 30-year global record which will continue for the forseeable future. So far, these snow retrievals have been generated primarily by regression-based empirical “inversion” methods based on snapshots in time, and are limited to footprints around 25 km in diameter. Assimilation of microwave radiances into physical land surface models may be used to create a retrieval framework that is inherently self-consistent with respect to model physics as well as a more physically-based approach vs. legacy retrieval/inversion methods. This radiance assimilation approach has been used for years for atmospheric parameters by the operational weather forecasting community with great success, and represents one motivation for our work. A radiance assimilation scheme for snow requires a snowpack land surface model (LSM) coupled to a radiative transfer model (RTM). In previous local-scale studies, Durand, Kim, & Margulis (2008) explored the requirements on LSM model fidelity (i.e., snowpack state information) required in order for the RTM to produce brightness temperatures suitable for radiance assimilation purposes at a local scale, using the well-known Microwave Emission Model for Layered Snowpacks (MEMLS) as the RTM and a combination of Simple SIB (SSiB) and Snow Atmosphere (SAST) as the LSM. They also demonstrated improvement of simulated snow depth through the use of an ensemble Kalman filter scheme at this local scale (2009). This modeling framework reflects another motivation—namely, possibilities for downscaling. Our focus at this stage has been at the local scale where high-quality ground truth data is available in order to evaluate radiance assimilation under a “best case scenario.” The quantitative results then form a benchmark for future assessment of effects such as sparse forcing data, upscaling/downscaling, forest attenuation, and model details. Field data from

  10. Genre theory in information studies

    CERN Document Server

    Andersen, Jack

    2015-01-01

    This book highlights the important role genre theory plays within information studies. It illustrates how modern genre studies inform and enrich the study of information, and conversely how the study of information makes its own independent contributions to the study of genre.

  11. How to Study a Matrix

    Science.gov (United States)

    Jairam, Dharmananda; Kiewra, Kenneth A.; Kauffman, Douglas F.; Zhao, Ruomeng

    2012-01-01

    This study investigated how best to study a matrix. Fifty-three participants studied a matrix topically (1 column at a time), categorically (1 row at a time), or in a unified way (all at once). Results revealed that categorical and unified study produced higher: (a) performance on relationship and fact tests, (b) study material satisfaction, and…

  12. Hungary country study

    Energy Technology Data Exchange (ETDEWEB)

    Uerge-Vorsatz, D.; Fuele, M. [eds.

    1999-09-01

    Hungary recognises the importance of limiting greenhouse gas emissions in order to prevent or mitigate their impact on the global climate. On an international level, Hungary is not a significant carbon dioxide emitter, neither to the absolute degree nor on a per capita basis. This means that the principal reason for Hungarian participation in emission`s reduction is not perceivable international consequences but solidarity and participation in the common action of the countries of the world. Hungary is a signatory to both the Framework Convention on Climate Change and the Kyoto protocol. However, the (Hungarian) National Environmental Program also emphasises that the fulfilment of international conventions must happen at a level and pace reasonable for Hungary. The goal of this study is to investigate the potentials, costs and implementation strategies of greenhouse gas abatement in Hungary. First presented is a background of Hungary`s economy and a summary of the economic transitions in Hungary. A brief description of the Hungarian energy sector is included, with a short summary of carbon dioxide emissions, and of the Hungarian forestry sector. The following chapter is devoted to the development of baseline scenarios, from bottom-up and top-down perspectives. In the chapter on mitigation, the spectrum of energy efficiency measures in the residential and public sectors is discussed. Fifteen specific measures, whose impact is considered important, are selected and discussed in detail. The cost curves are developed for the discussed mitigation options. Then, we discuss the issues related to the implementation of energy efficiency measures in the Hungarian residential and commercial sectors. After a general background and a framework on the implementation of the energy efficiency measures in the sectors chosen, we elaborate on the practicality of these concepts. As a case study, the concept and the feasibility of carbon/energy taxes are examined. To complete the

  13. STUDIES ON FLUTTER PREDICTION

    Directory of Open Access Journals (Sweden)

    Irina-Carmen ANDREI

    2012-03-01

    Full Text Available The purpose of this paper is to study the instability of the dynamic flutter. The justification is expressed by the fact that the occurrence of flutter within the aircraft’s flight envelope results in irreversible structural deformation which consequently leads to serious damage. Therefore the mathematical modeling of this phenomenon and its validation are very important. The instability of the dynamic flutter is characterized by critical speed and critical pulsation of oscillatory movements. In this paper, the quasi-stationary model and the Theodorsen model have been analyzed for calculating the aerodynamic forces and torques, and a comparison of them has been carried out. The fluid-structure coupling is done by rewriting the equations, considering that the forces are given by closed formulas. For the mathematical modeling of the flutter there have been used the p-k and V-g methods based on the Theodorsen model and the quasi-stationary model. In order to modeling the free vortices aerodynamic forces and moments, the equations which describe both the motion of the structure and the fluid flow had to be integrated simultaneously in time. The fluid-structure coupling is considered as a combination of two systems that describe the aeroelastic behavior of the structure.

  14. Electron microscope studies

    Energy Technology Data Exchange (ETDEWEB)

    Crewe, A.V.; Kapp, O.H.

    1990-08-01

    Our laboratory has made significant progress this year in devising improved electron-optical systems, in studying invertebrate hemoglobins with the STEM, and in achieving a workable sub-angstrom STEM. Our goal in electron optics is to improve resolution by producing spherical and chromatic aberration coefficients with signs opposite those of magnetic lenses. We have progressed toward this goal through calculations that explore the addition of electrodes to electron mirrors to reduce these two geometric aberrations and by devising a beam separation system that won't introduce asymmetrical aberrations. Some promising new designs of magnetic lenses for SEM applications have also been investigated. We have continued our exploration of the quaternary structure of the invertebrate hemoglobins and are now among the top laboratories in this area of expertise. In addition, we have overcome many of our electronic difficulties on the sub-angstrom STEM and have made significant progress toward achieving an operational system. The addition of an IBM RISC-6000 workstation to our lab has significantly increased our image processing capabilities.

  15. Case Study - Alpha

    Directory of Open Access Journals (Sweden)

    Stephen Leybourne

    2016-11-01

    Full Text Available This case study was developed from an actual scenario by Dr. Steve Leybourne of Boston University.  The case documents the historical evolution of an organization, and has been used successfully in courses dealing with organizational and cultural change, and the utilization of ‘soft skills’ in project-based management. This is a short case, ideal for classroom use and discussion.  The issues are easily accessible to students, and there is a single wide ranging question that allows for the inclusion of many issues surrounding strategic decision-making, and behavioural and cultural change. Alpha was one of the earlier companies in the USA to invest in large, edge-of-town superstores, with plentiful free vehicle parking, selling food and related household products. Alpha was created in the 1950s as a subsidiary of a major publicly quoted retail group.  It started business by opening a string of very large discount stores in converted industrial and warehouse premises in the south of the United States. In the early days shoppers were offered a limited range of very competitively priced products. When Alpha went public in 1981 it was the fourth largest food retailer in the US, selling an ever-widening range of food and non-food products.  Its success continued to be based on high volume, low margins and good value for money, under the slogan of ‘Alpha Price.’

  16. control study from India

    Directory of Open Access Journals (Sweden)

    Amitesh Aggarwal

    2014-03-01

    Full Text Available Introduction: The role of the conventional risk factors in premature coronary artery disease (CAD after eliminating the confounding variability of smoking has not been evaluated. This study was conducted to identify role of traditional risk factors in smokers with premature CAD.Methods: The case records of patients presenting acutely with premature CAD during the period 2007-2010 were analyzed retrospectively. Age, sex and smoking matched controls were selected from same time period. Data records were obtained for family history, alcohol, waist size, blood pressure, hypertension, blood sugar, lipid profile and presence of cutaneous markers for both groups and analyzed using statistical software.Results: 234 smokers with CAD and 122 smokers without CAD were included in groups 1 and 2, respectively. The patients in group 1 had significantly increased prevalence of hypertension, diabetes mellitus, metabolic syndrome, dyslipidemia and central obesity. There was no difference in prevalence of family history of CAD, arcus juvenilis and baldness. We found statistically significant association of hypertension, DM and metabolic syndrome in young smokers with premature acute CAD in Indian population as compared to young smokers without CAD.Conclusion: In young smokers, presence of hypertension, central obesity, diabetes mellitus and metabolic syndrome identifies a subset at increased risk for future acute CAD requiring more rigorous follow up and treatment.

  17. Maui energy storage study.

    Energy Technology Data Exchange (ETDEWEB)

    Ellison, James; Bhatnagar, Dhruv; Karlson, Benjamin

    2012-12-01

    This report investigates strategies to mitigate anticipated wind energy curtailment on Maui, with a focus on grid-level energy storage technology. The study team developed an hourly production cost model of the Maui Electric Company (MECO) system, with an expected 72 MW of wind generation and 15 MW of distributed photovoltaic (PV) generation in 2015, and used this model to investigate strategies that mitigate wind energy curtailment. It was found that storage projects can reduce both wind curtailment and the annual cost of producing power, and can do so in a cost-effective manner. Most of the savings achieved in these scenarios are not from replacing constant-cost diesel-fired generation with wind generation. Instead, the savings are achieved by the more efficient operation of the conventional units of the system. Using additional storage for spinning reserve enables the system to decrease the amount of spinning reserve provided by single-cycle units. This decreases the amount of generation from these units, which are often operated at their least efficient point (at minimum load). At the same time, the amount of spinning reserve from the efficient combined-cycle units also decreases, allowing these units to operate at higher, more efficient levels.

  18. ADVANCED CUTTINGS TRANSPORT STUDY

    Energy Technology Data Exchange (ETDEWEB)

    Troy Reed; Stefan Miska; Nicholas Takach; Kaveh Ashenayi; Mark Pickell; Len Volk, Mike Volk; Lei Zhou; Zhu Chen; Crystal Redden; Aimee Washington

    2002-10-30

    This is the first quarterly progress report for Year-4 of the ACTS Project. It includes a review of progress made in: (1) Flow Loop construction and development and (2) research tasks during the period of time between July 1, 2002 and Sept. 30, 2002. This report presents a review of progress on the following specific tasks: (a) Design and development of an Advanced Cuttings Transport Facility Task 3: Addition of a Cuttings Injection/Separation System, Task 4: Addition of a Pipe Rotation System, (b) New Research project (Task 9b): ''Development of a Foam Generator/Viscometer for Elevated Pressure and Elevated Temperature (EPET) Conditions'', (d) Research project (Task 10): ''Study of Cuttings Transport with Aerated Mud Under Elevated Pressure and Temperature Conditions'', (e) Research on three instrumentation tasks to measure: Cuttings concentration and distribution in a flowing slurry (Task 11), Foam texture while transporting cuttings (Task 12), Viscosity of Foam under EPET (Task 9b). (f) Development of a Safety program for the ACTS Flow Loop. Progress on a comprehensive safety review of all flow-loop components and operational procedures. (Task 1S). (g) Activities towards technology transfer and developing contacts with Petroleum and service company members, and increasing the number of JIP members.

  19. Heliostat cost reduction study.

    Energy Technology Data Exchange (ETDEWEB)

    Jones, Scott A.; Lumia, Ronald. (University of New Mexico, Albuquerque, NM); Davenport, Roger (Science Applications International Corporation, San Diego, CA); Thomas, Robert C. (Advanced Thermal Systems, Centennial, CO); Gorman, David (Advanced Thermal Systems, Larkspur, CO); Kolb, Gregory J.; Donnelly, Matthew W.

    2007-06-01

    Power towers are capable of producing solar-generated electricity and hydrogen on a large scale. Heliostats are the most important cost element of a solar power tower plant. Since they constitute {approx} 50% of the capital cost of the plant it is important to reduce heliostat cost as much as possible to improve the economic performance of power towers. In this study we evaluate current heliostat technology and estimate a price of $126/m{sup 2} given year-2006 materials and labor costs for a deployment of {approx}600 MW of power towers per year. This 2006 price yields electricity at $0.067/kWh and hydrogen at $3.20/kg. We propose research and development that should ultimately lead to a price as low as $90/m{sup 2}, which equates to $0.056/kWh and $2.75/kg H{sup 2}. Approximately 30 heliostat and manufacturing experts from the United States, Europe, and Australia contributed to the content of this report during two separate workshops conducted at the National Solar Thermal Test Facility.

  20. Power Plant Replacement Study

    Energy Technology Data Exchange (ETDEWEB)

    Reed, Gary

    2010-09-30

    This report represents the final report for the Eastern Illinois University power plant replacement study. It contains all related documentation from consideration of possible solutions to the final recommended option. Included are the economic justifications associated with the chosen solution along with application for environmental permitting for the selected project for construction. This final report will summarize the results of execution of an EPC (energy performance contract) investment grade audit (IGA) which lead to an energy services agreement (ESA). The project includes scope of work to design and install energy conservation measures which are guaranteed by the contractor to be self‐funding over its twenty year contract duration. The cost recovery is derived from systems performance improvements leading to energy savings. The prime focus of this EPC effort is to provide a replacement solution for Eastern Illinois University’s aging and failing circa 1925 central steam production plant. Twenty‐three ECMs were considered viable whose net impact will provide sufficient savings to successfully support the overall project objectives.

  1. Bioequivalence studies for levothyroxine.

    Science.gov (United States)

    Bolton, Sanford

    2005-03-30

    The Food and Drug Administration (FDA) Guidance for Bioavailability and Bioequivalence Studies for Levothyroxine has been challenged by companies that manufacture brand-name products. Their contention is that the current guidance does not adequately address the endogenous background levels of the drug, and that the ratios of the PK parameters, a basis for approval of equivalence, are not assessed correctly. In particular, they conclude that products that have a potency differing by 12.5% cannot be differentiated using the present guideline and criteria for acceptance of bioequivalence. They claim that such a difference can be a public health hazard because of the perception among practitioners that levothyroxine is a narrow therapeutic index drug. This article describes the procedure recommended in the current Guidance for Levothyroxine and demonstrates that the methods recommended are adequate and will accept products that are therapeutically equivalent. To date, no generic product accepted as equivalent using FDA Guidances has been shown to result in a safety and efficacy profile different from its brand counterpart.

  2. Yersinia enterocolitica Monographic Study

    Directory of Open Access Journals (Sweden)

    Emil Tirziu

    2011-10-01

    Full Text Available Germs from Yersinia genus have a vast ecologic niche, being met at different domestic and wild animal species, but also in food, water and soil. The majority of yersinis live in the digestive tract of human and numerous animal species, especially rodents, but also in soil, plant debris, waters etc. Numerous species of Yersinia genus could produce characteristic infections in human, the main source of infections is represented by rodents and hematophagous insects or, more frequently, by water or contaminated food. In a 1999 study, Mead and coauthors established that the Yersinia enterocolitica prevalence in food, in USA, is around 90%. Foods of animal origin more frequently contaminated with Yersinia enterocolitica are: pork, poultry, beef and lamb meat, milk, ice-cream, sea fruits etc., among them pork meat and milk represents the sources of the most numerous toxi-infection outbreaks in human, in different world regions. Bacteria determine infections which interest the digestive tract in numerous animal species and human, with diarrhea, lymphadenitis, pneumonia and abortion are the most important symptoms. Yersinia enterocolitica enter the human body regularly by oral ingestion, and localize itself with predilection in the distal portion of the ileum and at the ileocaecal appendix and proximal colon level, were determine a terminal ileitis with lymphadenitis, acute enterocolitis, and secondary accompanied with nodosum erythema, poliartritis that could be complicated with septicemia, sometimes leading to death.

  3. Power Plant Replacement Study

    Energy Technology Data Exchange (ETDEWEB)

    Reed, Gary

    2010-09-30

    This report represents the final report for the Eastern Illinois University power plant replacement study. It contains all related documentation from consideration of possible solutions to the final recommended option. Included are the economic justifications associated with the chosen solution along with application for environmental permitting for the selected project for construction. This final report will summarize the results of execution of an EPC (energy performance contract) investment grade audit (IGA) which lead to an energy services agreement (ESA). The project includes scope of work to design and install energy conservation measures which are guaranteed by the contractor to be self-funding over its twenty year contract duration. The cost recovery is derived from systems performance improvements leading to energy savings. The prime focus of this EPC effort is to provide a replacement solution for Eastern Illinois University's aging and failing circa 1925 central steam production plant. Twenty-three ECMs were considered viable whose net impact will provide sufficient savings to successfully support the overall project objectives.

  4. Dioxin: a case study.

    Science.gov (United States)

    Bond, G G

    1993-01-01

    The need to notify individuals of a possible health risk from their past exposure to potentially hazardous agents frequently extends beyond workers to include community groups. The issues to consider in community notification are frequently similar to those that are important for worker notification but may include some that are unique. This case study traces the evolution of one company's strategy for communicating with the public about possible dioxin contamination associated with its operations. Early communications tended to emphasize the technical aspects of the issues in the fashion of scientists talking to other scientists. This was interpreted by some to be symptomatic of an arrogant and uncaring attitude. Beginning in the early 1980s, the company's management recognized the need to reach out to a variety of audiences on multiple levels, and shifted to a more comprehensive communications strategy. A similar shift is now occurring throughout the chemical manufacturing industry as top managers realize that, if they expect to continue to operate, they must become more accountable and responsive to the public.

  5. Slurry reactor design studies

    Energy Technology Data Exchange (ETDEWEB)

    Fox, J.M.; Degen, B.D.; Cady, G.; Deslate, F.D.; Summers, R.L. (Bechtel Group, Inc., San Francisco, CA (USA)); Akgerman, A. (Texas A and M Univ., College Station, TX (USA)); Smith, J.M. (California Univ., Davis, CA (USA))

    1990-06-01

    The objective of these studies was to perform a realistic evaluation of the relative costs of tublar-fixed-bed and slurry reactors for methanol, mixed alcohols and Fischer-Tropsch syntheses under conditions where they would realistically be expected to operate. The slurry Fischer-Tropsch reactor was, therefore, operated at low H{sub 2}/CO ratio on gas directly from a Shell gasifier. The fixed-bed reactor was operated on 2.0 H{sub 2}/CO ratio gas after adjustment by shift and CO{sub 2} removal. Every attempt was made to give each reactor the benefit of its optimum design condition and correlations were developed to extend the models beyond the range of the experimental pilot plant data. For the methanol design, comparisons were made for a recycle plant with high methanol yield, this being the standard design condition. It is recognized that this is not necessarily the optimum application for the slurry reactor, which is being proposed for a once-through operation, coproducing methanol and power. Consideration is also given to the applicability of the slurry reactor to mixed alcohols, based on conditions provided by Lurgi for an Octamix{trademark} plant using their standard tubular-fixed reactor technology. 7 figs., 26 tabs.

  6. Boston Washer Study

    Energy Technology Data Exchange (ETDEWEB)

    Tomlinson, J.J.

    2002-08-06

    To help understand the relative performance gains of conventional and high-efficiency washers and to increase awareness of energy/water savings, the U.S. Department of Energy under its Emerging Technologies Program and in cooperation with Maytag Appliances conducted a field-evaluation of horizontal axis washers in a Boston, Massachusetts condo complex. Baseline washer and dryer performance and customer habits were established using 50 participants and their existing, instrumented washers and dryers for a 2 1/2-month period. After the baseline was established, the machines were replaced with high efficiency tumble action washers and moisture sensing dryers, and tested for the next 2 1/2 months. By information gathered, energy and water savings delivered by the h-axis washers as well as impacts on participants' washing habits and perceptions of cleaning performance were determined. Overall, participants saved 41% of the water and 50% of the energy that they would have used without a changeover to the new h-axis washer. The changeover also produced significant dryer energy savings due primarily to the high-speed final spin of the new washer. The Boston Washer Study report details the experiment including instrumentation, data collection and analysis procedures and discusses the impacts on energy, water and detergent consumption as well as customer satisfaction with the technology.

  7. Power Plant Replacement Study

    Energy Technology Data Exchange (ETDEWEB)

    Reed, Gary

    2010-09-30

    This report represents the final report for the Eastern Illinois University power plant replacement study. It contains all related documentation from consideration of possible solutions to the final recommended option. Included are the economic justifications associated with the chosen solution along with application for environmental permitting for the selected project for construction. This final report will summarize the results of execution of an EPC (energy performance contract) investment grade audit (IGA) which lead to an energy services agreement (ESA). The project includes scope of work to design and install energy conservation measures which are guaranteed by the contractor to be self-funding over its twenty year contract duration. The cost recovery is derived from systems performance improvements leading to energy savings. The prime focus of this EPC effort is to provide a replacement solution for Eastern Illinois University’s aging and failing circa 1925 central steam production plant. Twenty-three ECMs were considered viable whose net impact will provide sufficient savings to successfully support the overall project objectives.

  8. Three Studies in Epicurean Cosmology

    NARCIS (Netherlands)

    Bakker, F.A.

    2010-01-01

    This dissertation consists of three studies dealing with various aspects of Epicurean cosmology. The first study discusses the Epicurean practice of explaining astronomical and meteorological phenomena by multiple alternative theories. The second study compares the meteorological accounts of Epicuru

  9. Nevada Transportatoion Options Study

    Energy Technology Data Exchange (ETDEWEB)

    P. GEHNER; E.M. WEAVER; L. FOSSUM

    2006-05-25

    This study performs a cost and schedule analysis of three Nevada Transportation options that support waste receipt at the repository. Based on the U.S. Department of Energy preference for rail transportation in Nevada (given in the Final Environmental Impact Statement), it has been assumed that a branch rail line would be constructed to support waste receipt at the repository. However, due to potential funding constraints, it is uncertain when rail will be available. The three Nevada Transportation options have been developed to meet a varying degree of requirements for transportation and to provide cost variations used in meeting the funding constraints given in the Technical Direction Letter guidelines for this study. The options include combinations of legal-weight truck, heavy-haul truck, and rail. Option 1 uses a branch rail line that would support initial waste receipt at the repository in 2010. Rail transportation would be the primary mode, supplemented by legal weight trucks. This option provides the highest level of confidence in cost and schedule, lowest public visibility, greatest public acceptability, lowest public dose, and is the recommended option for support of waste receipt. The completion of rail by 2010 will require spending approximately $800 million prior to 2010. Option 2 uses a phased rail approach to address a constrained funding scenario. To meet funding constraints, Option 2 uses a phased approach to delay high cost activities (final design and construction) until after initial waste receipt in 2010. By doing this, approximately 95 percent of the cost associated with completion of a branch rail line is deferred until after 2010. To support waste receipt until a branch rail line is constructed in Nevada, additional legal-weight truck shipments and heavy-haul truck shipments (on a limited basis for naval spent nuclear fuel) would be used to meet the same initial waste receipt rates as in Option 1. Use of heavy-haul shipments in the absence

  10. Microscale Immune Studies Laboratory.

    Energy Technology Data Exchange (ETDEWEB)

    Poschet, Jens Fredrich; Carroll-Portillo, Amanda; Wu, Meiye; Manginell, Ronald Paul; Herr, Amy Elizabeth; Martino, Anthony A.; Perroud, Thomas D.; Branda, Catherine; Srivastava, Nimisha; Sinclair, Michael B.; Moorman, Matthew Wallace; Apblett, Christopher Alan; Sale, Kenneth L.; James, Conrad D.; Carles, Elizabeth L.; Lidke, Diane S. (University of New Mexico, Albuquerque, NM); Van Benthem, Mark Hilary; Rebeil, Roberto; Kaiser, Julie; Seaman, William (University of California, San Francisco, CA); Rempe, Susan; Brozik, Susan Marie; Jones, Howland D. T.; Gemperline, Paul (East Carolina University, Greenville, NC); Throckmorton, Daniel J.; Misra, Milind; Murton, Jaclyn K.; Carson, Bryan D.; Zhang, Zhaoduo; Plimpton, Steven James; Renzi, Ronald F.; Lane, Todd W.; Ndiaye-Dulac, Elsa; Singh, Anup K.; Haaland, David Michael; Faulon, Jean-Loup Michel; Davis, Ryan W.; Ricken, James Bryce; Branda, Steven S.; Patel, Kamlesh D.; Joo, Jaewook; Kubiak, Glenn D.; Brennan, James S.; Martin, Shawn Bryan; Brasier, Allan (University of Texas Mecial Branch, Galveston, TX)

    2009-01-01

    The overarching goal is to develop novel technologies to elucidate molecular mechanisms of the innate immune response in host cells to pathogens such as bacteria and viruses including the mechanisms used by pathogens to subvert/suppress/obfuscate the immune response to cause their harmful effects. Innate immunity is our first line of defense against a pathogenic bacteria or virus. A comprehensive 'system-level' understanding of innate immunity pathways such as toll-like receptor (TLR) pathways is the key to deciphering mechanisms of pathogenesis and can lead to improvements in early diagnosis or developing improved therapeutics. Current methods for studying signaling focus on measurements of a limited number of components in a pathway and hence, fail to provide a systems-level understanding. We have developed a systems biology approach to decipher TLR4 pathways in macrophage cell lines in response to exposure to pathogenic bacteria and their lipopolysaccharide (LPS). Our approach integrates biological reagents, a microfluidic cell handling and analysis platform, high-resolution imaging and computational modeling to provide spatially- and temporally-resolved measurement of TLR-network components. The Integrated microfluidic platform is capable of imaging single cells to obtain dynamic translocation data as well as high-throughput acquisition of quantitative protein expression and phosphorylation information of selected cell populations. The platform consists of multiple modules such as single-cell array, cell sorter, and phosphoflow chip to provide confocal imaging, cell sorting, flow cytomtery and phosphorylation assays. The single-cell array module contains fluidic constrictions designed to trap and hold single host cells. Up to 100 single cells can be trapped and monitored for hours, enabling detailed statistically-significant measurements. The module was used to analyze translocation behavior of transcription factor NF-kB in macrophages upon activation

  11. GROUT HOPPER MODELING STUDY

    Energy Technology Data Exchange (ETDEWEB)

    Lee, S.

    2011-08-30

    The Saltstone facility has a grout hopper tank to provide agitator stirring of the Saltstone feed materials. The tank has about 300 gallon capacity to provide a larger working volume for the grout slurry to be held in case of a process upset, and it is equipped with a mechanical agitator, which is intended to keep the grout in motion and agitated so that it won't start to set up. The dry feeds and the salt solution are already mixed in the mixer prior to being transferred to the hopper tank. The hopper modeling study through this work will focus on fluid stirring and agitation, instead of traditional mixing in the literature, in order to keep the tank contents in motion during their residence time so that they will not be upset or solidified prior to transferring the grout to the Saltstone disposal facility. The primary objective of the work is to evaluate the flow performance for mechanical agitators to prevent vortex pull-through for an adequate stirring of the feed materials and to estimate an agitator speed which provides acceptable flow performance with a 45{sup o} pitched four-blade agitator. In addition, the power consumption required for the agitator operation was estimated. The modeling calculations were performed by taking two steps of the Computational Fluid Dynamics (CFD) modeling approach. As a first step, a simple single-stage agitator model with 45{sup o} pitched propeller blades was developed for the initial scoping analysis of the flow pattern behaviors for a range of different operating conditions. Based on the initial phase-1 results, the phase-2 model with a two-stage agitator was developed for the final performance evaluations. A series of sensitivity calculations for different designs of agitators and operating conditions have been performed to investigate the impact of key parameters on the grout hydraulic performance in a 300-gallon hopper tank. For the analysis, viscous shear was modeled by using the Bingham plastic approximation

  12. Microscale Immune Studies Laboratory.

    Energy Technology Data Exchange (ETDEWEB)

    Poschet, Jens Fredrich; Carroll-Portillo, Amanda; Wu, Meiye; Manginell, Ronald Paul; Herr, Amy Elizabeth; Martino, Anthony A.; Perroud, Thomas D.; Branda, Catherine; Srivastava, Nimisha; Sinclair, Michael B.; Moorman, Matthew Wallace; Apblett, Christopher Alan; Sale, Kenneth L.; James, Conrad D.; Carles, Elizabeth L.; Lidke, Diane S. (University of New Mexico, Albuquerque, NM); Van Benthem, Mark Hilary; Rebeil, Roberto; Kaiser, Julie; Seaman, William (University of California, San Francisco, CA); Rempe, Susan; Brozik, Susan Marie; Jones, Howland D. T.; Gemperline, Paul (East Carolina University, Greenville, NC); Throckmorton, Daniel J.; Misra, Milind; Murton, Jaclyn K.; Carson, Bryan D.; Zhang, Zhaoduo; Plimpton, Steven James; Renzi, Ronald F.; Lane, Todd W.; Ndiaye-Dulac, Elsa; Singh, Anup K.; Haaland, David Michael; Faulon, Jean-Loup Michel; Davis, Ryan W.; Ricken, James Bryce; Branda, Steven S.; Patel, Kamlesh D.; Joo, Jaewook; Kubiak, Glenn D.; Brennan, James S.; Martin, Shawn Bryan; Brasier, Allan (University of Texas Mecial Branch, Galveston, TX)

    2009-01-01

    The overarching goal is to develop novel technologies to elucidate molecular mechanisms of the innate immune response in host cells to pathogens such as bacteria and viruses including the mechanisms used by pathogens to subvert/suppress/obfuscate the immune response to cause their harmful effects. Innate immunity is our first line of defense against a pathogenic bacteria or virus. A comprehensive 'system-level' understanding of innate immunity pathways such as toll-like receptor (TLR) pathways is the key to deciphering mechanisms of pathogenesis and can lead to improvements in early diagnosis or developing improved therapeutics. Current methods for studying signaling focus on measurements of a limited number of components in a pathway and hence, fail to provide a systems-level understanding. We have developed a systems biology approach to decipher TLR4 pathways in macrophage cell lines in response to exposure to pathogenic bacteria and their lipopolysaccharide (LPS). Our approach integrates biological reagents, a microfluidic cell handling and analysis platform, high-resolution imaging and computational modeling to provide spatially- and temporally-resolved measurement of TLR-network components. The Integrated microfluidic platform is capable of imaging single cells to obtain dynamic translocation data as well as high-throughput acquisition of quantitative protein expression and phosphorylation information of selected cell populations. The platform consists of multiple modules such as single-cell array, cell sorter, and phosphoflow chip to provide confocal imaging, cell sorting, flow cytomtery and phosphorylation assays. The single-cell array module contains fluidic constrictions designed to trap and hold single host cells. Up to 100 single cells can be trapped and monitored for hours, enabling detailed statistically-significant measurements. The module was used to analyze translocation behavior of transcription factor NF-kB in macrophages upon activation

  13. Solids Accumulation Scouting Studies

    Energy Technology Data Exchange (ETDEWEB)

    Duignan, M. R.; Steeper, T. J.; Steimke, J. L.

    2012-09-26

    The objective of Solids Accumulation activities was to perform scaled testing to understand the behavior of remaining solids in a Double Shell Tank (DST), specifically AW-105, at Hanford during multiple fill, mix, and transfer operations. It is important to know if fissionable materials can concentrate when waste is transferred from staging tanks prior to feeding waste treatment plants. Specifically, there is a concern that large, dense particles containing plutonium could accumulate in poorly mixed regions of a blend tank heel for tanks that employ mixing jet pumps. At the request of the DOE Hanford Tank Operations Contractor, Washington River Protection Solutions, the Engineering Development Laboratory of the Savannah River National Laboratory performed a scouting study in a 1/22-scale model of a waste staging tank to investigate this concern and to develop measurement techniques that could be applied in a more extensive study at a larger scale. Simulated waste tank solids: Gibbsite, Zirconia, Sand, and Stainless Steel, with stainless steel particles representing the heavier particles, e.g., plutonium, and supernatant were charged to the test tank and rotating liquid jets were used to mix most of the solids while the simulant was pumped out. Subsequently, the volume and shape of the mounds of residual solids and the spatial concentration profiles for the surrogate for heavier particles were measured. Several techniques were developed and equipment designed to accomplish the measurements needed and they included: 1. Magnetic particle separator to remove simulant stainless steel solids. A device was designed and built to capture these solids, which represent the heavier solids during a waste transfer from a staging tank. 2. Photographic equipment to determine the volume of the solids mounds. The mounds were photographed as they were exposed at different tank waste levels to develop a composite of topographical areas. 3. Laser rangefinders to determine the volume of

  14. Hydrogen energy systems studies

    Energy Technology Data Exchange (ETDEWEB)

    Ogden, J.M.; Kreutz, T.G.; Steinbugler, M. [Princeton Univ., NJ (United States)] [and others

    1996-10-01

    In this report the authors describe results from technical and economic assessments carried out during the past year with support from the USDOE Hydrogen R&D Program. (1) Assessment of technologies for small scale production of hydrogen from natural gas. Because of the cost and logistics of transporting and storing hydrogen, it may be preferable to produce hydrogen at the point of use from more readily available energy carriers such as natural gas or electricity. In this task the authors assess near term technologies for producing hydrogen from natural gas at small scale including steam reforming, partial oxidation and autothermal reforming. (2) Case study of developing a hydrogen vehicle refueling infrastructure in Southern California. Many analysts suggest that the first widespread use of hydrogen energy is likely to be in zero emission vehicles in Southern California. Several hundred thousand zero emission automobiles are projected for the Los Angeles Basin alone by 2010, if mandated levels are implemented. Assuming that hydrogen vehicles capture a significant fraction of this market, a large demand for hydrogen fuel could evolve over the next few decades. Refueling a large number of hydrogen vehicles poses significant challenges. In this task the authors assess near term options for producing and delivering gaseous hydrogen transportation fuel to users in Southern California including: (1) hydrogen produced from natural gas in a large, centralized steam reforming plant, and delivered to refueling stations via liquid hydrogen truck or small scale hydrogen gas pipeline, (2) hydrogen produced at the refueling station via small scale steam reforming of natural gas, (3) hydrogen produced via small scale electrolysis at the refueling station, and (4) hydrogen from low cost chemical industry sources (e.g. excess capacity in refineries which have recently upgraded their hydrogen production capacity, etc.).

  15. FET noise studies

    Science.gov (United States)

    Pucel, R. A.

    1981-03-01

    The GaAs FET oscillator is an alternative device for voltage-controlled oscillator (VCO) applications because of its inherent wide-band electronic tunability, the variety of operating modes possible such as common source, common gate, etc., and the ease of circuit design. However, it has one major drawback, namely, its high near-carrier 1/f noise which makes it unsuitable for many applications, such as radar systems. This report describes the progress made during the report period in understanding the physical mechanisms responsible for this noise. During this period, an extensive experimental study was made of the 1/f noise properties of a variety of oscillators constructed of FET chips fabricated under controlled conditions. Using in-house grown epitaxial wafers, FET's were fabricated from both buffered and unbuffered active layers, with and without epitaxially grown contact layers, and with and without surface passivation. The experimental results show a good correlation between the trap-generated 1/f baseband noise and the near-carrier 1/f FM noise. The primary sources of the noise are presumed to be either deep traps within the depletion layer under the gate or surface states at the gate-semiconductor interface, probably the latter. An improvement of the order of 10 dB in the near carrier FM noise level is obtained when a buffer layer separates the active layer from the substrate. Optical experiments indicated an electron trap level approximately 0.41 eV below the conduction band. A noise model was devised to explain the modulation process for upconverting baseband 1/f noise to the carrier band by depletion layer modulation.

  16. Bioreactor Mass Transport Studies

    Science.gov (United States)

    Kleis, Stanley J.; Begley, Cynthia M.

    1997-01-01

    The objectives of the proposed research efforts were to develop both a simulation tool and a series of experiments to provide a quantitative assessment of mass transport in the NASA rotating wall perfused vessel (RWPV) bioreactor to be flown on EDU#2. This effort consisted of a literature review of bioreactor mass transport studies, the extension of an existing scalar transport computer simulation to include production and utilization of the scalar, and the evaluation of experimental techniques for determining mass transport in these vessels. Since mass transport at the cell surface is determined primarily by the relative motion of the cell assemblage and the surrounding fluid, a detailed assessment of the relative motion was conducted. Results of the simulations of the motion of spheres in the RWPV under microgravity conditions are compared with flight data from EDU#1 flown on STS-70. The mass transport across the cell membrane depends upon the environment, the cell type, and the biological state of the cell. Results from a literature review of cell requirements of several scalars are presented. As a first approximation, a model with a uniform spatial distribution of utilization or production was developed and results from these simulations are presented. There were two candidate processes considered for the experimental mass transport evaluations. The first was to measure the dissolution rate of solid or gel beads. The second was to measure the induced fluorescence of beads as a stimulant (for example hydrogen peroxide) is infused into the vessel. Either technique would use video taped images of the process for recording the quantitative results. Results of preliminary tests of these techniques are discussed.

  17. Microbial field pilot study

    Energy Technology Data Exchange (ETDEWEB)

    Knapp, R.M.; McInerney, M.J.; Menzie, D.E.; Chisholm, J.L.

    1992-03-01

    The objective of this project is to perform a microbial enhanced oil recovery field pilot in the Southeast Vassar Vertz Sand Unit (SEVVSU) in Payne County, Oklahoma. Indigenous, anaerobic, nitrate reducing bacteria will be stimulated to selectively plug flow paths which have been referentially swept by a prior waterflood. This will force future flood water to invade bypassed regions of the reservoir and increase sweep efficiency. This report covers progress made during the second year, January 1, 1990 to December 31, 1990, of the Microbial Field Pilot Study project. Information on reservoir ecology, surface facilities design, operation of the unit, core experiments, modeling of microbial processes, and reservoir characterization and simulation are presented in the report. To better understand the ecology of the target reservoir, additional analyses of the fluids which support bacteriological growth and the microbiology of the reservoir were performed. The results of the produced and injected water analysis show increasing sulfide concentrations with respect to time. In March of 1990 Mesa Limited Partnership sold their interest in the SEVVSU to Sullivan and Company. In April, Sullivan and Company assumed operation of the field. The facilities for the field operation of the pilot were refined and implementation was begun. Core flood experiments conducted during the last year were used to help define possible mechanisms involved in microbial enhanced oil recovery. The experiments were performed at SEVVSU temperature using fluids and inoculum from the unit. The model described in last year's report was further validated using results from a core flood experiment. The model was able to simulate the results of one of the core flood experiments with good quality.

  18. Microbial field pilot study

    Energy Technology Data Exchange (ETDEWEB)

    Knapp, R.M.; McInerney, M.J.; Menzie, D.E.; Chisholm, J.L.

    1992-03-01

    The objective of this project is to perform a microbial enhanced oil recovery field pilot in the Southeast Vassar Vertz Sand Unit (SEVVSU) in Payne County, Oklahoma. Indigenous, anaerobic, nitrate reducing bacteria will be stimulated to selectively plug flow paths which have been referentially swept by a prior waterflood. This will force future flood water to invade bypassed regions of the reservoir and increase sweep efficiency. This report covers progress made during the second year, January 1, 1990 to December 31, 1990, of the Microbial Field Pilot Study project. Information on reservoir ecology, surface facilities design, operation of the unit, core experiments, modeling of microbial processes, and reservoir characterization and simulation are presented in the report. To better understand the ecology of the target reservoir, additional analyses of the fluids which support bacteriological growth and the microbiology of the reservoir were performed. The results of the produced and injected water analysis show increasing sulfide concentrations with respect to time. In March of 1990 Mesa Limited Partnership sold their interest in the SEVVSU to Sullivan and Company. In April, Sullivan and Company assumed operation of the field. The facilities for the field operation of the pilot were refined and implementation was begun. Core flood experiments conducted during the last year were used to help define possible mechanisms involved in microbial enhanced oil recovery. The experiments were performed at SEVVSU temperature using fluids and inoculum from the unit. The model described in last year`s report was further validated using results from a core flood experiment. The model was able to simulate the results of one of the core flood experiments with good quality.

  19. Microbial field pilot study

    Energy Technology Data Exchange (ETDEWEB)

    Knapp, R.M.; McInerney, M.J.; Menzie, D.E.; Coates, J.D.; Chisholm, J.L.

    1993-05-01

    A multi-well microbially enhanced oil recovery field pilot has been performed in the Southeast Vassar Vertz Sand Unit in Payne County, Oklahoma. The primary emphasis of the experiment was preferential plugging of high permeability zones for the purpose of improving waterflood sweep efficiency. Studies were performed to determine reservoir chemistry, ecology, and indigenous bacteria populations. Growth experiments were used to select a nutrient system compatible with the reservoir that encouraged growth of a group of indigenous nitrate-using bacteria and inhibit growth of sulfate-reducing bacteria. A specific field pilot area behind an active line drive waterflood was selected. Surface facilities were designed and installed. Injection protocols of bulk nutrient materials were prepared to facilitate uniform distribution of nutrients within the pilot area. By the end of December, 1991, 82.5 tons (75.0 tonnes) of nutrients had been injected in the field. A tracer test identified significant heterogeneity in the SEVVSU and made it necessary to monitor additional production wells in the field. The tracer tests and changes in production behavior indicate the additional production wells monitored during the field trial were also affected. Eighty two and one half barrels (13.1 m[sup 3]) of tertiary oil have been recovered. Microbial activity has increased CO[sub 2] content as indicated by increased alkalinity. A temporary rise in sulfide concentration was experienced. These indicate an active microbial community was generated in the field by the nutrient injection. Pilot area interwell pressure interference test results showed that significant permeability reduction occurred. The interwell permeabilities in the pilot area between the injector and the three pilot production wells were made more uniform which indicates a successful preferential plugging enhanced oil recovery project.

  20. Confinement studies in TFTR

    Energy Technology Data Exchange (ETDEWEB)

    Murakami, M.; Arunasalam, V.; Bell, J.D.; Bell, M.G.; Bitter, M.; Blanchard, W.R.; Boody, F.; Boyd, D.; Bretz, N.; Bush, C.E.

    1985-06-01

    The paper describes the present (end of February 1985) status of the plasma confinement studies in the TFTR tokamak with emphasis on those with neutral beam injection (NBI). Recent improvements in the device capabilities have substantially extended operating parameters: B/sub T/ increased to 4.0 T, I/sub p/ to 2.0 MA, injection power (P/sub b/) to 5 MW with H/sup 0/ or D/sup 0/ beams anti n/sub e/ to 5 x 10/sup 19/ m/sup -3/, and Z/sub eff/ reduced to 1.4. With ohmic heating (OH) alone, the previously established scaling for gross energy confinement time (tau/sub E/ = anti n/sub e/q) has been confirmed at higher I/sub p/ and B/sub T/, and the maximum tau/sub E/ of 0.4 sec has been achieved. With NBI at P/sub b/ substantially (by factor >2) higher than P/sub OH/, excellent power and particle accountability have been established. This suggests that the less-than-expected increase in stored energy with NBI is not due to problems of power delivery, but due to problems of confinement deterioration. tau/sub E/ is observed to scale approximately as I/sub p/ P/sub b//sup -0.5/ (independent of anti n/sub e/), consistent with previous L-mode scalings. With NBI we have achieved the maximum tau/sub E/ of 0.2 sec and the maximum T/sub i/(o) of 4.4 keV in the normal operating regime, and even higher T/sub i/(o) in the energetic-ion regime with low-n/sub e/ and low-I/sub p/ operation.

  1. Volcanic studies at Katmai

    Energy Technology Data Exchange (ETDEWEB)

    1989-12-31

    The Continental Scientific Drilling Program (CSDP) is a national effort supported by the Department of Energy, the US Geological Survey, and the National Science Foundation. One of the projects proposed for the CSDP consists of drilling a series of holes in Katmai National Park in Alaska to give a third dimension to the model of the 1912 eruption of Novarupta, and to investigate the processes of explosive volcanism and hydrothermal transport of metals (Eichelberger et al., 1988). The proposal for research drilling at Katmai states that ``the size, youth, elevated temperature, and simplicity of the Novarupta vent make it a truly unique scientific target.`` The National Park Service (NPS), which has jurisdiction, is sympathetic to aims of the study. However, NPS wishes to know whether Katmai is indeed uniquely suited to the research, and has asked the Interagency Coordinating Group to support an independent assessment of this claim. NPS suggested the National Academy of Sciences as an appropriate organization to conduct the assessment. In response, the National Research Council -- the working arm of the Academy -- established, under the aegis of its US Geodynamics Committee, a panel whose specific charge states: ``The proposed investigation at Katmai has been extensively reviewed for scientific merit by the three sponsoring and participating agencies. Thus, the scientific merit of the proposed drilling at Katmai is not at issue. The panel will review the proposal for scientific drilling at Katmai and prepare a short report addressing the specific question of the degree to which it is essential that the drilling be conducted at Katmai as opposed to volcanic areas elsewhere in the world.``

  2. Comparative waste forms study

    Energy Technology Data Exchange (ETDEWEB)

    Wald, J.W.; Lokken, R.O.; Shade, J.W.; Rusin, J.M.

    1980-12-01

    A number of alternative process and waste form options exist for the immobilization of nuclear wastes. Although data exists on the characterization of these alternative waste forms, a straightforward comparison of product properties is difficult, due to the lack of standardized testing procedures. The characterization study described in this report involved the application of the same volatility, mechanical strength and leach tests to ten alternative waste forms, to assess product durability. Bulk property, phase analysis and microstructural examination of the simulated products, whose waste loading varied from 5% to 100% was also conducted. The specific waste forms investigated were as follows: Cold Pressed and Sintered PW-9 Calcine; Hot Pressed PW-9 Calcine; Hot Isostatic Pressed PW-9 Calcine; Cold Pressed and Sintered SPC-5B Supercalcine; Hot Isostatic pressed SPC-5B Supercalcine; Sintered PW-9 and 50% Glass Frit; Glass 76-68; Celsian Glass Ceramic; Type II Portland Cement and 10% PW-9 Calcine; and Type II Portland Cement and 10% SPC-5B Supercalcine. Bulk property data were used to calculate and compare the relative quantities of waste form volume produced at a spent fuel processing rate of 5 metric ton uranium/day. This quantity ranged from 3173 L/day (5280 Kg/day) for 10% SPC-5B supercalcine in cement to 83 L/day (294 Kg/day) for 100% calcine. Mechanical strength, volatility, and leach resistance tests provide data related to waste form durability. Glass, glass-ceramic and supercalcine ranked high in waste form durability where as the 100% PW-9 calcine ranked low. All other materials ranked between these two groupings.

  3. ADVANCED CUTTINGS TRANSPORT STUDY

    Energy Technology Data Exchange (ETDEWEB)

    Troy Reed; Stefan Miska; Nicholas Takach; Kaveh Ashenayi; Mark Pickell; Len Volk; Mike Volk; Lei Zhou; Zhu Chen; Crystal Redden; Aimee Washington

    2003-04-30

    Experiments on the flow loop are continuing. Improvements to the software for data acquisition are being made as additional experience with three-phase flow is gained. Modifications are being made to the Cuttings Injection System in order to improve control and the precision of cuttings injection. The design details for a drill-pipe Rotation System have been completed. A US Patent was filed on October 28, 2002 for a new design for an instrument that can generate a variety of foams under elevated pressures and temperatures and then transfer the test foam to a viscometer for measurements of viscosity. Theoretical analyses of cuttings transport phenomena based on a layered model is under development. Calibrations of two nuclear densitometers have been completed. Baseline tests have been run to determine wall roughness in the 4 different tests sections (i.e. 2-in, 3-in, 4-in pipes and 5.76-in by 3.5-in annulus) of the flow loop. Tests have also been conducted with aerated fluids at EPET conditions. Preliminary experiments on the two candidate aqueous foam formulations were conducted which included rheological tests of the base fluid and foam stability reports. These were conducted after acceptance of the proposal on the Study of Cuttings Transport with Foam Under Elevated Pressure and Elevated Temperature Conditions. Preparation of a test matrix for cuttings-transport experiments with foam in the ACTF is also under way. A controller for instrumentation to measure cuttings concentration and distribution has been designed that can control four transceivers at a time. A prototype of the control circuit board was built and tested. Tests showed that there was a problem with radiated noise. AN improved circuit board was designed and sent to an external expert to verify the new design. The new board is being fabricated and will first be tested with static water and gravel in an annulus at elevated temperatures. A series of viscometer tests to measure foam properties have

  4. Studies of pancreatic carcinogenesis

    Institute of Scientific and Technical Information of China (English)

    JI Yu-bin; PANG Lin-lin; YU Lei; YANG Hai-fan; LIU Guang-da; LI Hai-jiao

    2008-01-01

    Pancreatic carcinoma is the most common pancreatic neoplasm characterized by latentmorbidit, poor prognosis, high mortality rate and limited choice of treatment. Quite a lot studies focused on its pathogenesis, and showed molecular genetic alterations, which derived of genetic and environmental factors and played an important role in tumorigenesis. Recently, more and more findings laid particular emphasis on the changes of gene molecule and some were confirmed in vitro and in vivo. In this paper, we made a review and summarized the arked molecular changes and signalings of the four pathways to understand their functions in Pancreatic carcinoma. The most important changes concentrate on K-RAS, p16 INK4α, P53 and SMAD4 gene, secondly, the changes of pl4ARF, TGF-β, LKB1 /STK11, BRCA2 and growth factor Hedgehog and Notch path way and Telomere also play a important role in pancreatic carcinoma. The vast majority (83%) of pancreatic carcinomas had a distinctive genetic fingerprint, comprising activation of the K-ras oncogene and inactivation of the p 16 gene, generally also accompanied by alterations in the p53 gene (in 76 % of the tumors). The activation of K-ras appears nearly to be a prerequisite for the development of pancreatic carcinoma. Also, the binary alteration of K-ras and p16 is an extremely uncommon combination among other human tumor types. This particular genetic imprint of pancreatic carcinomas could have diagnostic utility in the evaluation of patients with metastatic adenocarcinoma of unknown primary origin. The evaluation of genetic alterations as they naturally occur in humantumors allows the formulation of hypotheses concerning the biological processes that involve human tumongenesis. A central tenet of tumori genesis, that positive selection is exerted upon those tumor cells that alterrate-limiting regulatory pathways, implies that mutation of one gene abrogates the need for inactivation of another gene in the same tumor suppressive pathway. It

  5. Biological Sampling Variability Study

    Energy Technology Data Exchange (ETDEWEB)

    Amidan, Brett G. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Hutchison, Janine R. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2016-11-08

    There are many sources of variability that exist in the sample collection and analysis process. This paper addresses many, but not all, sources of variability. The main focus of this paper was to better understand and estimate variability due to differences between samplers. Variability between days was also studied, as well as random variability within each sampler. Experiments were performed using multiple surface materials (ceramic and stainless steel), multiple contaminant concentrations (10 spores and 100 spores), and with and without the presence of interfering material. All testing was done with sponge sticks using 10-inch by 10-inch coupons. Bacillus atrophaeus was used as the BA surrogate. Spores were deposited using wet deposition. Grime was coated on the coupons which were planned to include the interfering material (Section 3.3). Samples were prepared and analyzed at PNNL using CDC protocol (Section 3.4) and then cultured and counted. Five samplers were trained so that samples were taken using the same protocol. Each sampler randomly sampled eight coupons each day, four coupons with 10 spores deposited and four coupons with 100 spores deposited. Each day consisted of one material being tested. The clean samples (no interfering materials) were run first, followed by the dirty samples (coated with interfering material). There was a significant difference in recovery efficiency between the coupons with 10 spores deposited (mean of 48.9%) and those with 100 spores deposited (mean of 59.8%). There was no general significant difference between the clean and dirty (containing interfering material) coupons or between the two surface materials; however, there was a significant interaction between concentration amount and presence of interfering material. The recovery efficiency was close to the same for coupons with 10 spores deposited, but for the coupons with 100 spores deposited, the recovery efficiency for the dirty samples was significantly larger (65

  6. Bentonite erosion. Laboratory studies

    Energy Technology Data Exchange (ETDEWEB)

    Jansson, Mats (Div. of Nuclear Chemistry, Royal Inst. of Technology, Stockholm (Sweden), School of Chemical Science and Engineering)

    2009-11-15

    This report covers the laboratory studies that have been performed at Nuclear Chemistry, KTH in the project 'Bentonite Erosion'. Many of the experiments in this report were performed to support the work of the modelling group and were often relatively simple. One of the experiment series was performed to see the impact of gravity and concentration of mono- and di-valent cations. A clay suspension was prepared in a test tube. A net was placed in contact with the suspension, the test tube was filled with solutions of different concentrations and the system was left overnight to settle. The tube was then turned upside down and the behaviour was visually observed. Either the clay suspension fell through the net or stayed on top. By using this method surprisingly sharp determinations of the Critical Coagulation (Flocculation) Concentration (CCC/CFC) could be made. The CCC/CFC of Ca2+ was for sodium montmorillonite determined to be between 1 and 2 mM. An artificial fracture was manufactured in order to simulate the real case scenario. The set-up was two Plexiglas slabs separated by 1 mm thick spacers with a bentonite container at one side of the fracture. Water was pumped with a very low flow rate perpendicular to bentonite container and the water exiting the fracture was sampled and analyzed for colloid content. The bentonite used was treated in different ways. In the first experiment a relatively montmorillonite rich clay was used while in the second bentonite where only the readily soluble minerals had been removed was used. Since Plexiglas was used it was possible to visually observe the bentonite dispersing into the fracture. After the compacted bentonite (1,000 kg/m3) had been water saturated the clay had expanded some 12 mm out into the fracture. As the experiment progressed the clay expanded more out into the fracture and seemed to fractionate in two different phases with less material in the outmost phase. A dark rim which was later analyzed to contain

  7. New Historicism in Translation Studies

    Directory of Open Access Journals (Sweden)

    Mir Mohammad Khadem-Nabi

    2014-11-01

    Full Text Available Translation Studies has moved from linguistically oriented approaches to a historicist one. This is evident in many recent publications, and has brought about new trends in Translation Studies as well as in Cultural Studies. This paper is an attempt at summarizing the influence of the historicist approaches on translation. Of specific importance for this paper is New Historicism, which has poststructuralist tendencies.  Keywords: New Historicism, translation studies, cultural studies

  8. Children and Clinical Studies: Why Clinical Studies Are Important

    Medline Plus

    Full Text Available ... about Children and Clinical Studies Importance of Children in Clinical Studies Children have often had to accept ... treatments based on what is known to work in adults. To improve clinical care of children, more ...

  9. GuLF Study: The Gulf Long-Term Follow-Up Study

    Science.gov (United States)

    ... Studies Study Publications Mexico Childhood Asthma Studies Mexico Childhood Asthma Study Publications MOBAND Study of Cerebral Palsy Studies MOBAND Study of Cerebral Palsy Publications North Carolina Infant Feeding Study Studies North Carolina Infant Feeding Study Study ...

  10. Observational research methods—Cohort studies, cross sectional studies, and case–control studies

    Directory of Open Access Journals (Sweden)

    C.J. Mann

    2012-03-01

    Cohort studies are used to study incidence, causes, and prognosis. Because they measure events in chronological order they can be used to distinguish between cause and effect. Cross sectional studies are used to determine prevalence. They are relatively quick and easy but do not permit distinction between cause and effect. Case controlled studies compare groups retrospectively. They seek to identify possible predictors of outcome and are useful for studying rare diseases or outcomes. They are often used to generate hypotheses that can then be studied via prospective cohort or other studies.

  11. Curriculum Studies in Brasil: A Study of the Teaching Practice.

    Science.gov (United States)

    Marcondes, Maria Ines; Tura, Maria de Lourdes Rangel; de Macedo, Elizabeth Fernandes

    This study analyzes how undergraduate university teachers are thinking in the classroom about the theoretical and practical contents related to the subject called "Curriculum Studies." The study focuses on the aspects of the theory-practice relationship, the idea of curriculum, and the theoretical references used by the undergraduate…

  12. Urban Studies: A Study of Bibliographic Access and Control.

    Science.gov (United States)

    Anderson, Barbara E.

    This paper analyzes: (1) the bibliographic access to publications in urban studies via printed secondary sources; (2) development and scope of classification systems and of vocabulary control for urban studies; and (3) currently accessible automated collections of bibliographic citations. Urban studies is defined as "an agglomeration of…

  13. Correlative study between the angiotensin converting enzyme gene polymorphism and cerebrovascular diseases in Naxi population in Yunnan province%云南纳西族人群血管紧张素转换酶基因多态性与脑血管病的相关性研究

    Institute of Scientific and Technical Information of China (English)

    许虹; 范茜君; 袁齐宏; 常履华; 聂志; 何国强

    2011-01-01

    Objective To investigate the correlation between the angiotensin-converting enzyme(ACE)gene insertion/deletion(I/D)polymorphism and cerebrovascular diseases in Naxi population in Lijiang,Yunnan province.Methods Fifty-eight Naxi patients with cerebral infarction,32 Naxi patients with intracerebral hemorrhage,and 50 sex- and age-matched Naxi healthy controls were recruited.Polymerase chain reaction-restricted fragments length polymorphism was used to detect the ACE gene polymorphism and perform bidirectional sequencing Results The DD genotype and the D allele frequency in the cerebral infarction group were significantly higher than those in the healthy control group(32.8% vs.16.0%,P = 0.045 and 54.3% vs.39.0%,P =0.025);while there were no significant differences in the DD genotype and the D allele frequency between the intracerebral hemorrhage group and the control group.The different types of cerebral infarction carried different allele frequencies,they were in order of cerebral embolism < cerebral thrombosis < lacunar infarction.The DD genotype in patients with lacunar infarction(40.0% vs.30.0%,P = 0.481 )and the D allele frequencies(63.3% vs.51.2%,P =0.257)were all higher than those in patients with cerebral thrombosis,but there were no significant differences.Conclusions The ACE DD genotype carriers were susceptible to cerebral infarction in Naxi poulation in Yunan province.%目的 探讨血管紧张素转换酶(angiotension-convertion enzyme,ACE)基因插入/缺失(insertion/deletion,I/D)多态性与云南丽江纳西族脑血管病的相关性.方法 纳入58例纳西族脑梗死患者、32例纳西族脑出血患者以及50例性别和年龄相匹配的纳西族健康对照者,采用聚合酶链反应-限制性片段长度多态性技术进行ACE基因多态性检测和双向测序.结果 脑梗死组DD基因型(32.8%对16.0%,P=0.045)和D等位基因(54.3%对39.0%,P=0.025)频率均显著高于对照组,而脑出血组DD基因型和D等位基因频率与

  14. Local Community Studies In Social Studies Course: An Action Research

    Directory of Open Access Journals (Sweden)

    Tuğba Selanik Ay

    2011-05-01

    Full Text Available Social Studies can be defined as “bonding process based on verification with social reality and dynamic information obtained as a result of this process”. In this context, it is essential to unify the Social Studies course with the real life and to benefit from the society in teaching-learning process in order to enable the learned information to be applied in the real life. In the Social Studies course, students should encounter with the real life itself. Thus, students can produce multidimensional alternative solutions for the cases they encounter and they can explain the best solution with justifications. Considering these arguments, it can be claimed that involving the subjects and studies related to the society and near environment in the Social Studies courses increases the effectiveness of Social Studies teaching. Local community studies, which are associated with the Social Studies program by means of a detailed and good plan, can draw students’ attention and thus permanent learning can occur. In this sense, teachers should benefit from the local community studies in the Social Studies course which reflects the real life.The aim of this study is to determine how local community studies will be applied in Social Studies course in the primary education schools. In line with this aim, the following research questions were addressed:1. How can the activities ofa. benefitting from institutions and organizations in local communitiesb. benefitting from people in local communitiesc. using Internet and library sourcesd. benefitting from special days and current eventswhich are carried out in the Social Studies course taught with local community studies, be arranged?2. Do the local community studies help the students determine the problems in their environments and find out the solutions for these problems?3. What are the students’ opinions about the Social Studies course taught with local community studies ?4. Does the Social Studies

  15. Goddard Institute for Space Studies

    Data.gov (United States)

    National Aeronautics and Space Administration — Research at the NASA Goddard Institute for Space Studies (GISS) emphasizes a broad study of global change, which is an interdisciplinary initiative addressing...

  16. Laguna Atascosa Wilderness study area

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This document is a brief report on a wilderness study area located in the Laguna Atascosa National Wildlife Refuge. It discusses the history of the study area, its...

  17. Studies Update Vinyl Chloride Hazards.

    Science.gov (United States)

    Rawls, Rebecca

    1980-01-01

    Extensive study affirms that vinyl chloride is a potent animal carcinogen. Epidemiological studies show elevated rates of human cancers in association with extended contact with the compound. (Author/RE)

  18. The Scope of Design Studying

    Institute of Scientific and Technical Information of China (English)

    JIN Yin; Ren Wenying

    2007-01-01

    This article trys to discuss the scope of design studying in two fields.Firstly, design has three meanings: wide design, art design and industrial design.Secondly, design studying has five contents: cultural, philosophical, methodological, produced and marketable trends.

  19. Mechanistic studies of olefin metathesis

    Energy Technology Data Exchange (ETDEWEB)

    Grubbs, R.H.

    1979-03-01

    A review covers studies of the olefin metathesis mechanism which indicated that the reaction proceeds by a non-pairwise mechanism; detailed mechanistic studies on the homogeneously and heterogeneously catalyzed metathesis; and stereochemical investigations.

  20. Program evaluation and case study

    OpenAIRE

    Kushner, S

    2009-01-01

    This entry looks at the convergence of case study methodology and program evaluation. An early insight of some educational evaluation theorists was of the convergence of case study and program evaluation – the fusion of method with purpose. Program evaluation and case study came to be mutually-bracketed. In the educational evaluation field 'Responsive', 'Democratic', 'Illuminative' methodologies were developed in parallel with case study methods - the same authors contributing freely to both ...