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Sample records for temporal precedence based

  1. Optimal Solutions for the Temporal Precedence Problem

    DEFF Research Database (Denmark)

    Brodal, Gerth Stølting; Makris, Christos; Sioutas, Spyros

    2002-01-01

    In this paper we refer to the Temporal Precedence Problem on Pure Pointer Machines . This problem asks for the design of a data structure, maintaining a set of stored elements and supporting the following two operations: insert and precedes . The operation insert (a) introduces a new element a in...

  2. A temporal precedence based clustering method for gene expression microarray data

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    Buchanan-Wollaston Vicky

    2010-01-01

    Full Text Available Abstract Background Time-course microarray experiments can produce useful data which can help in understanding the underlying dynamics of the system. Clustering is an important stage in microarray data analysis where the data is grouped together according to certain characteristics. The majority of clustering techniques are based on distance or visual similarity measures which may not be suitable for clustering of temporal microarray data where the sequential nature of time is important. We present a Granger causality based technique to cluster temporal microarray gene expression data, which measures the interdependence between two time-series by statistically testing if one time-series can be used for forecasting the other time-series or not. Results A gene-association matrix is constructed by testing temporal relationships between pairs of genes using the Granger causality test. The association matrix is further analyzed using a graph-theoretic technique to detect highly connected components representing interesting biological modules. We test our approach on synthesized datasets and real biological datasets obtained for Arabidopsis thaliana. We show the effectiveness of our approach by analyzing the results using the existing biological literature. We also report interesting structural properties of the association network commonly desired in any biological system. Conclusions Our experiments on synthesized and real microarray datasets show that our approach produces encouraging results. The method is simple in implementation and is statistically traceable at each step. The method can produce sets of functionally related genes which can be further used for reverse-engineering of gene circuits.

  3. Visual object cognition precedes but also temporally overlaps mental rotation.

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    Schendan, Haline E; Lucia, Lisa C

    2009-10-19

    Two-dimensional, mental rotation of alphanumeric characters and geometric figures is related to linear increases in parietal negativity between 400 and 800 ms as rotation increases, similar to linear increases with rotation in response times. This suggests that the frontoparietal networks implicated in mental rotation are engaged after 400 ms. However, the time course of three-dimensional object mental rotation using the classic Shepard-Metzler task has not been studied, even though this is one of the most commonly used versions in behavioral and neuroimaging work. Using this task, this study replicated a prior neuroimaging version using event-related potentials. Results confirmed linear mental rotation effects on performance and parietal negativity. In addition, a frontocentral N350 complex that indexes visual object cognition processes was more negative with mental rotation and showed linear trends at frontopolar sites from 200 to 700 ms and centrofrontal sites from 400 to 500 ms. The centrofrontal negativity has been implicated in object working memory processes in ventrolateral prefrontal and occipitotemporal areas. The frontopolar N350 has been implicated in processes that compute the spatial relations among parts of objects to resolve visual differences between object representations and enable an accurate cognitive decision involving a network of ventrocaudal intraparietal, ventral premotor, and inferotemporal cortices. Overall, the time course indicates that visual object cognition processes precede (200-500 ms) but also overlap the initial phase of mental rotation (500-700 ms) indexed by parietal negativity.

  4. Internalising symptoms and body dissatisfaction: untangling temporal precedence using cross-lagged models in two cohorts.

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    Patalay, Praveetha; Sharpe, Helen; Wolpert, Miranda

    2015-11-01

    Cross-sectional studies demonstrate that body dissatisfaction and internalising symptoms are correlated and are both overrepresented in girls compared to boys. However, it is not clear whether body dissatisfaction typically precedes internalising symptoms or vice versa. Existing literature provides theoretical and empirical support for both possibilities, but is limited in two ways: (a) no study has simultaneously tested the two temporal hypotheses within the same model, and (b) the studies focus almost exclusively on early adolescents resulting in little being known about development from preadolescence and across puberty. This study used data from 5485 primary school students (49.1% girls, aged 8-9 years at baseline) and 5981 secondary school students (53.9% girls, aged 11-12 years at baseline). Self-reports of internalising symptoms and body dissatisfaction were collected over three consecutive years at 1-year intervals. Cross-lagged models were estimated in the two cohorts, for boys and girls separately, to examine the temporal associations between these two domains across the three measurement points. In the younger cohort, internalising symptoms predicted body dissatisfaction 1-year later for both boys and girls, whereas there was no evidence for the reverse being true. In the older cohort, internalising symptoms predicted later body dissatisfaction for boys. However, in girls, body dissatisfaction predicted later internalising symptoms. In preadolescents, internalising symptoms drive later body dissatisfaction regardless of gender, suggesting body dissatisfaction is a specific manifestation of a tendency towards negative affect. From age 11, girls develop a distinct risk profile whereby body dissatisfaction drives later internalising symptoms. Preventative interventions in this field would benefit from adopting a developmentally sensitive approach that takes into account gender differences in risk pathways. © 2015 The Authors. Journal of Child Psychology

  5. Planning school based sexuality programs utilizing the PRECEDE model.

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    Rubinson, L; Baillie, L

    1981-04-01

    Both substantive and methodological issues in teenage sexuality were explored. Specific study purposes were the following: 1) to explore the effectiveness of a community needs assessment to reduce traditional negative parental input and facilitating the use of the schools as public health resources; 2) to identify substantive targets of intervention for curriculum development which would be accepted and supported by both parents and teenagers; and 3) to develop a methodology of assessment where the PRECEDE model would be tested for its utility in identifying educational targets in a complex and multidimensional area such as human sexuality and to quantify the model's categories to identify major differences in perceptions between parents and teenagers, and to explore underlying constructs in teenage sexuality. The PRECEDE model provides an assessment of social and epidemiological factors as well as an investigation of the behavioral causes of the outcomes as identified by the community. 50% of the population of 600 families living in a small midwestern community were surveyed: 204 parents and 210 teenagers responded to the survey. The following were among the major findings: 1) a community needs assessment using the PRECEDE model was effective in reducing negative political input and in facilitating the use of the schools as public health resources; 2) there were major needs, especially in the identification of important social problems; and 3) 24% of the teenagers reported they were sexually active while only 10% of the parents perceived their children as being sexually active.

  6. Calciphylaxis: Temporal Artery Calcification Preceding Widespread Skin Lesions and Penile Necrosis

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    Manzoor A. Shah

    2012-01-01

    Full Text Available Temporal artery calciphylaxis has rarely been described in chronic kidney disease patients on dialysis. We report a case of 72-year-old Caucasian man with multiple comorbidities and end-stage renal disease on dialysis who presented with temporal artery calcification leading to bilateral loss of vision followed by extensive skin lesions including one on glans penis. While on peritoneal dialysis, he developed anterior ischemic optic neuropathy, had no improvement on high dose steroids, and temporal artery biopsy showed marked calcification without any evidence of vasculitis. Few weeks later on hemodialysis, he developed widespread cutaneous lesions on extremities and penile necrosis with skin biopsy revealing calciphylaxis. On literature review of calciphylaxis in chronic kidney disease, we found only four cases of temporal artery calciphylaxis leading to anterior ischemic optic neuropathy and blindness. We believe this is the first case in which the rare temporal artery calciphylaxis and the uncommon penile necrosis are being described together. The objective is to emphasize the need to recognize this condition early in the CKD patients on dialysis presenting with visual symptoms as the different treatment strategies may help prevent complete loss of vision and also modify or prevent a full blown calciphylaxis.

  7. Combining offsets with precedence constraints to improve temporal analysis of cyclic real-time streaming applications

    NARCIS (Netherlands)

    Kurtin, Philip Sebastian; Hausmans, J.P.H.M.; Bekooij, Marco Jan Gerrit

    2016-01-01

    Stream processing applications executed on multiprocessor systems usually contain cyclic data dependencies due to the presence of bounded FIFO buffers and feedback loops, as well as cyclic resource dependencies due to the usage of shared processors. In recent works it has been shown that temporal

  8. SILAC-Based Temporal Phosphoproteomics

    DEFF Research Database (Denmark)

    Francavilla, Chiara; Hekmat, Omid; Blagoev, Blagoy

    2014-01-01

    In recent years, thanks to advances in Mass Spectrometry (MS)-based quantitative proteomics, studies on signaling pathways have moved from a detailed description of individual components to system-wide analysis of entire signaling cascades, also providing spatio-temporal views of intracellular...... tyrosines by immunoaffinity and then further enriched for phosphorylated serine/threonine peptides by strong cation exchange in combination with titanium dioxide-beads chromatography. Analysis of enriched peptides on Orbitrap-based MS results in comprehensive and accurate reconstruction of temporal changes...... signaling events. Here we provide an optimized SILAC-based proteomic workflow to analyze temporal changes in phosphoproteomes, which involve a generic three step enrichment protocol for phosphopeptides. SILAC-labeled peptides from digested whole cell lysates are as a first step enriched for phosphorylated...

  9. Temporal patterns of change in vital signs and Cardiac Arrest Risk Triage scores over the 48 hours preceding fatal in-hospital cardiac arrest.

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    Oh, HyunSoo; Lee, KangIm; Seo, WhaSook

    2016-05-01

    To determine temporal patterns of vital sign and Cardiac Arrest Risk Triage score changes over the 48-hour period preceding cardiac arrest in an ICU setting. Vital sign instability usually occurs prior to cardiac arrest. However, few studies have been conducted on the temporal patterns of individual vital signs preceding cardiac arrest. A retrospective case-control study. The study subjects were 140 ICU patients (1 June 2011-31 December 2012): 46 died of cardiac arrest (case group), 45 died of other illnesses (control I group) and 49 were discharged after recovering (control II group). Initial detectable changes in blood pressure appeared 18-20 hours and became dramatic at 5-10 hours before cardiac arrest. Noticeable changes in heart rates began at 4 hours and became more prominent at 2 hours pre-arrest. No apparent patterns in respiratory rate changes were observed. Body temperatures usually indicated a hypothermic state pre-arrest. Cardiac Arrest Risk Triage scores were 16-18 at 48 hours pre-arrest and then continuously increased to 20. Only mean values of systolic blood pressures were significantly different between the three study groups. Mean diastolic blood pressures, heart rates, respiratory rates and Cardiac Arrest Risk Triage scores differed between the case and control II groups and between the control I and II groups. The study demonstrates vital sign instability preceded cardiac arrest and that the temporal patterns of changes in individual vital signs and Cardiac Arrest Risk Triage scores differed between groups. The findings of this study may aid the development of management strategies for cardiac arrest. © 2016 John Wiley & Sons Ltd.

  10. Development of a Home Food Safety Questionnaire Based on the PRECEDE Model: Targeting Iranian Women.

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    Esfarjani, Fatemeh; Hosseini, Hedayat; Mohammadi-Nasrabadi, Fatemeh; Abadi, Alireza; Roustaee, Roshanak; Alikhanian, Haleh; Khalafi, Marjan; Kiaee, Mohammad Farhad; Khaksar, Ramin

    2016-12-01

    Food safety is an essential public health issue for all countries. This study was the first attempt to design and develop a home food safety questionnaire (HFSQ), in the conceptual framework of the PRECEDE (predisposing, reinforcing, and enabling constructs in educational diagnosis and evaluation) model, and to assess its validity and reliability. The HFSQ was developed by reviewing electronic databases and 12 focus group discussions with 96 women volunteers. Ten panel members reviewed the questionnaire, and the content validity ratio and content validity index were computed. Twenty women completed the HFSQ, and face validity was assessed. Women who were responsible for food handling in their households (n =320) were selected randomly from 10 health centers and completed the HFSQ based on the PRECEDE model. To examine the construct validity, a principal components factor analysis with varimax rotation was used. Internal consistency was determined with Cronbach's α. Reproducibility was checked by Kendall's τ after 4 weeks with 30 women. The developed HSFQ was considered acceptable with a content validity index of 0.88. Face validity revealed that 95% of the participants understood the questions and found them easy to answer, and 90% confirmed the appearance of the HFSQ and declared the layout acceptable. Principal component factor analysis revealed that the HFSQ could explain 33.7, 55.3, 34.8, and 60.0% of the total variance of the predisposing, reinforcing, practice, and enabling components, respectively. Cronbach's α was acceptable at 0.73. For Kendall's τc, r = 0.89, with a 95% confidence interval of 0.85 to 0.93. The HFSQ developed based on the PRECEDE model met the standards of acceptable reliability and validity, which can be generalized to a wider population. These results can provide information for the development of effective communication strategies to promote home food safety.

  11. Transient isolated brainstem symptoms preceding posterior circulation stroke: a population-based study.

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    Paul, Nicola L M; Simoni, Michela; Rothwell, Peter M

    2013-01-01

    Transient isolated brainstem symptoms (eg, isolated vertigo, dysarthria, diplopia) are not consistently classified as transient ischaemic attacks (TIAs) and data for prognosis are limited. If some of these transient neurological attacks (TNAs) are due to vertebrobasilar ischaemia, then they should be common during the days and weeks preceding posterior circulation strokes. We aimed to assess the frequency of TNAs before vertebrobasilar ischaemic stroke. We studied all potential ischaemic events during the 90 days preceding an ischaemic stroke in patients ascertained within a prospective, population-based incidence study in Oxfordshire, UK (Oxford Vascular Study; 2002-2010) and compared rates of TNA preceding vertebrobasilar stroke versus carotid stroke. We classified the brainstem symptoms isolated vertigo, vertigo with non-focal symptoms, isolated double vision, transient generalised weakness, and binocular visual disturbance as TNAs in the vertebrobasilar territory; atypical amaurosis fugax and limb-shaking as TNAs in the carotid territory; and isolated slurred speech, migraine variants, transient confusion, and hemisensory tingling symptoms as TNAs in uncertain territory. Of the 1141 patients with ischaemic stroke, vascular territory was categorisable in 1034 (91%) cases, with 275 vertebrobasilar strokes and 759 carotid strokes. Isolated brainstem TNAs were more frequent before a vertebrobasilar stroke (45 of 275 events) than before a carotid stroke (10 of 759; OR 14·7, 95% CI 7·3-29·5, pstroke vs two of 751 before a carotid stroke, OR 35·8, 8·4-153·5, pstroke, only five (8%) fulfilled the National Institute of Neurological Disorders and Stroke (NINDS) criteria for TIA. The other 54 cases were isolated vertigo (n=23), non-NINDS binocular visual disturbance (n=9), vertigo with other non-focal symptoms (n=10), isolated slurred speech, hemisensory tingling, or diplopia (n=8), and non-focal events (n=4). Only 10 (22%) of the 45 patients with isolated brainstem

  12. Cross-spectral and temporal factors in the precedence effect: discrimination suppression of the lag sound in free-field.

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    Yang, X; Grantham, D W

    1997-11-01

    In an anechoic chamber, subjects were required to discriminate a 20 degrees azimuthal change in a lag sound's position in the presence of a lead sound coming from a different direction. Delay between lead and lag sounds was adaptively varied in several conditions to track discrimination suppression thresholds. In experiment 1, lead and lag stimuli were 5-ms, 1-octave, A-weighted noise bursts (65 dB), with lead and lag parametrically set to center frequencies of 0.5, 2.0, or 3.0 kHz. Discrimination suppression thresholds were higher when lead and lag center frequencies coincided (mean: 11.3 ms) than when they did not coincide (mean: 2.9 ms). These results support the "spectral overlap hypothesis" of Blauert and Divenyi [Acustica 66, 267-274 (1988)], but not the "localization strength hypothesis" later proposed by Divenyi [J. Acoust. Soc. Am. 91, 1078-1084 (1992)]. Spectral overlap and localization strength appear to be two relatively independent factors governing discrimination suppression. It is proposed here that localization strength is weighted more when stimuli are presented via headphones and the only cue to lateral position is the interaural temporal difference, while spectral overlap is weighted more for free-field presented stimuli. In experiment 2, lead and lag stimuli were 8-ms, 1.5-kHz A-weighted tone bursts (65 dB), with lead and lag rise times parametrically set to 0, 2, or 4 ms. In this case the amount of discrimination suppression increased as lead rise time became more abrupt or as lag rise time became more gradual. These results support the localization strength hypothesis: The greater the localization strength of the lead stimulus (independently assessed by measuring its minimum audible angle in isolation), the greater suppression it exerted on discriminability of the lag sound's position. It appears that for stimuli presented in the free-field, spectral overlap is the primary factor affecting discrimination suppression, but when overlap is held

  13. Fault Tolerant PLBGSA: Precedence Level Based Genetic Scheduling Algorithm for P2P Grid

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    Piyush Chauhan

    2013-01-01

    Full Text Available Due to monetary limitation, small organizations cannot afford high end supercomputers to solve highly complex tasks. P2P (peer to peer grid computing is being used nowadays to break complex task into subtasks in order to solve them on different grid resources. Workflows are used to represent these complex tasks. Finishing such complex task in a P2P grid requires scheduling subtasks of workflow in an optimized manner. Several factors play their part in scheduling decisions. The genetic algorithm is very useful in scheduling DAG (directed acyclic graph based task. Benefit of a genetic algorithm is that it takes into consideration multiple criteria while scheduling. In this paper, we have proposed a precedence level based genetic algorithm (PLBGSA, which yields schedules for workflows in a decentralized fashion. PLBGSA is compared with existing genetic algorithm based scheduling techniques. Fault tolerance is a desirable trait of a P2P grid scheduling algorithm due to the untrustworthy nature of grid resources. PLBGSA handles faults efficiently.

  14. Effect of precede model-based education on quality of life in patients with type 2 diabetes

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    Ahmad Moradi

    2017-07-01

    Full Text Available The increasing prevalence rate has made diabetes a world epidemic. Considering diabetes complications and associated effects on patients’ quality of life, this interventional study was performed to promote the life quality using education based on the Precede model in the rural areas of Andimeshk. This experimental study was conducted on 120 patients with type II diabetes who were randomly allocated to the experimental and control groups. The data were collected using two questionnaires including the Precede model framework and Short Form health survey (SF-36. The precede model-based intervention composed of six educational sessions (60 to 90 minutes a session. The patients were followed up for three months post-intervention and examined for glycated hemoglobin (Hemoglobin A1c or HbAlc. After educational intervention, the mean score of quality of life had a significant increase in the experimental group compared with the control group.The mean scores of Precede model constructs inpatients of the experimental group increased significantly after the intervention compared with the before intervention. Moreover, the mean score of HbA1c improved significantly in the experimental group compared to the control group. The present study indicated that the educational intervention program based on the Precede model has a positive effect on quality of life among diabetic patients.

  15. The temporal order of change in daily mindfulness and affect during mindfulness-based stress reduction

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    Snippe, E.; Nyklicek, I.; Schroevers, M.

    2015-01-01

    Increases in mindfulness are assumed to lead to improvements in psychological well-being during mindfulness-based treatments. However, the temporal order of this association has received little attention. This intensive longitudinal study examines whether within-person changes in mindfulness precede

  16. The Temporal Order of Change in Daily Mindfulness and Affect During Mindfulness-Based Stress Reduction

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    Snippe, Evelien; Nyklicek, Ivan; Schroevers, Maya J.; Bos, Elisabeth H.

    Increases in mindfulness are assumed to lead to improvements in psychological well-being during mindfulness-based treatments. However, the temporal order of this association has received little attention. This intensive longitudinal study examines whether within-person changes in mindfulness precede

  17. Effect of Stress Management Training Based on PRECEDE Model on Prehospital Emergency Staff Occupational Tension in Mazandaran University of Medical Sciences in 2016

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    Gholamreza Esmailzadeh Gatabi

    2017-10-01

    Conclusion: The findings showed that education based on PRECEDE model increases the predisposing factor (knowledge and attitude, reinforcing factor, and enhancer factor. These factors have the potential to affect the behavior more effectively. According to this, educational intervention based on PRECEDE model structures is effective on job stress and behavior. Researchers have suggested training on this pattern.

  18. Audiovisual laughter detection based on temporal features

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    Petridis, Stavros; Pantic, Maja

    2008-01-01

    Previous research on automatic laughter detection has mainly been focused on audio-based detection. In this study we present an audio-visual approach to distinguishing laugh- ter from speech based on temporal features and we show that integrating the information from audio and video chan- nels leads

  19. Sound localization in reverberant environments: physiological bases of the precedence effect

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    Paterson, Miles Andrew McLean

    Localization dominance, a phenomenon of the precedence effect, refers to the dominance of directional cues conveyed by sound arriving directly from the source over cues conveyed by reflected copies on the perception of sound source location. One theory of localization dominance is that leading sounds suppress neural responses to lagging sounds (Yin, 1994 Litovsky & Yin, 1998 a, b). Neurons in auditory nuclei respond best to a leading sound and have a reduced response to a lagging sound, supporting this hypothesis. It has been proposed that GABA-ergic or glycinergic inhibition suppresses neural responses to lagging sounds (Yin, 1994 Fitzpatrick et al. 1995 Pollack & Burger, 2002). An alternative hypothesis states that cochlear processing in low-frequency hearing animals alters directional cues conveyed by the leading and lagging sound, emphasising those present in the leading sound (Tollin, 1998 Hartung & Trahiotis 2001). Responses of single neurons in the inferior colliculus (IC) of anaesthetised guinea pigs were recorded to binaural click pair stimuli. Responses of some neurons were recorded before, during, and after iontophoresis of either the GABAa receptor antagonist gabazine, or the glycine receptor antagonist strychnine. Blocking glycine did not decrease neural suppression of the lagging click in 8/10 neurons. Blocking GAB A did not decrease neural suppression of the lagging click in 11/16 neurons. The neural representation of directional cues in the output of low-frequency neurons to the leading click of a binaural click pair differed from those actually conveyed by the stimulus in 20/20 neurons. Examination of the responses of several such neurons indicated responses to the leading click represented a direction between that conveyed by the leading and lagging click. The results supported the hypothesis that cochlear processing of binaural click pairs alters directional cues conveyed by the stimulus. Limited support was also found for the hypothesis that

  20. Effectiveness of a PRECEDE-based education intervention on quality of life in elderly patients with chronic heart failure.

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    Wang, Qiong; Dong, Lini; Jian, Zaijin; Tang, Xianghua

    2017-10-16

    One of the most important challenges in public health is to improve the quality of life in patients with chronic heart failure (CHF). Depression, self-care capacity, and quality of life interact each other in these patients. It's difficult to treat with general education programs and conventional therapy. PRECEDE model is a comprehensive and exclusive theory-based education programs. Its effectiveness for reducing depression and increasing quality of life has been demonstrated in patients with coronary artery bypass grafting, type 2 diabetes, and the elderly. It has not been used in elderly patients with CHF. Thus, this study aims to investigate the effects of this model on self-care behaviors, depression, and quality of life in these patients. Patients who met the inclusion criteria were randomly assigned to the intervention or control group. All the patients received conventional medical care. The patients in the intervention group also received 9 sessions of education intervention based on the PRECEDE model and then followed up for 3 months after the intervention. Data were collected before and 3 months after the intervention using 4 questionnaires, namely a PRECEDE-based questionnaire to evaluate predisposing, reinforcing, and enabling factors; the 9-item European Heart Failure Self-care Behavior Scale (EHFScBS-9); the 9-item Personal Health Questionnaire (PHQ-9); and the Minnesota Living with Heart Failure Questionnaire (MLHFQ). No significant differences were found in the mean scores for the predisposing, enabling, and reinforcing factors, and the mean total scores in EHFScBS-9, PHQ-9, and MLHFQ before the intervention between the intervention and control groups. After the intervention, the scores for the predisposing, reinforcing, and enabling factors increased significantly, and the mean total scores in EHFScBS-9, PHQ-9, and MLHFQ decreased significantly in the intervention group. In addition, these scores significantly differed from those of the control

  1. Applying an Educational-participatory Program based on the PRECEDE Model for Promoting Self-esteem and Mental Health of Students in Iran

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    Mahdi Moshki

    2012-01-01

    Conclusion: Health promotion planning by using life skills training based on the PRECEDE model can result in participation and empowerment, in order to promote the self-esteem and mental health of the students.

  2. Health-Promoting Lifestyle of Adolescents with β-Thalassemia Based on Precede Model in Ahvaz, Iran, 2016

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    Gheibizadeh

    2016-09-01

    Full Text Available Background Lifestyle as a health promotion component contains six dimensions of stress management, health-responsibility, interpersonal relationships, spiritual growth, nutrition and physical activity. The current study aimed to determine the health-promoting lifestyle of adolescents with β-thalassemia, based on Precede model to analyze behavior. Methods It was a descriptive cross-sectional study conducted in February 2016 on 64 adolescents with β-thalassemia and the age range of 16 - 20 years selected by census sampling method. Data were collected by two self-reporting questionnaires; health-promoting lifestyle profile (HPLP II and a researcher-made questionnaire based on Precede model. Data were analyzed using SPSS ver. 22 by applying descriptive statistics of absolute and relative frequency distribution, central tendency, mean and standard deviation, and analytical statistics of spearman correlation and Mann-Whitney U test. Results The mean age of participants was 17.98 ± 1.36 years and the mean overall score of lifestyle of adolescents under study was 106.23 ± 8.54. Based on the findings of the current study, the overall lifestyle of adolescents with β-thalassemia was correlated with their knowledge and attitude. In addition, the standardized mean score of knowledge was greater in females than males (P value = 0.05. Conclusions Overall health-promoting lifestyle of the studied adolescents with β-thalassemia was unsatisfactory. Due to the impact of adopted lifestyle on the current and future health of adolescents, it is important that the necessary measures are taken to encourage more young people with β-thalassemia to adopt a healthy lifestyle.

  3. Schiff base switch II precedes the retinal thermal isomerization in the photocycle of bacteriorhodopsin.

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    Ting Wang

    Full Text Available In bacteriorhodopsin, the order of molecular events that control the cytoplasmic or extracellular accessibility of the Schiff bases (SB are not well understood. We use molecular dynamics simulations to study a process involved in the second accessibility switch of SB that occurs after its reprotonation in the N intermediate of the photocycle. We find that once protonated, the SB C15 = NZ bond switches from a cytoplasmic facing (13-cis, 15-anti configuration to an extracellular facing (13-cis, 15-syn configuration on the pico to nanosecond timescale. Significantly, rotation about the retinal's C13 = C14 double bond is not observed. The dynamics of the isomeric state transitions of the protonated SB are strongly influenced by the surrounding charges and dielectric effects of other buried ions, particularly D96 and D212. Our simulations indicate that the thermal isomerization of retinal from 13-cis back to all-trans likely occurs independently from and after the SB C15 = NZ rotation in the N-to-O transition.

  4. Survey on quality of life related factors in patients with peptic ulcer based on PRECEDE model in Yazd, Iran.

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    Baghianimoghadam, M H; Mohamadi, S; Baghianimoghadam, M; Falahi, A; Roghani, H S

    2011-11-14

    Peptic ulcer is one of the most prevalent diseases. Its prevalence is estimated between 6-15% and, about 10% of the people, experience its symptom in a period of their life. Studies showed that quality of life and health status of peptic ulcer patients is affected by disease. The aim of this study was to determine the Quality of life Related Factors in patients with peptic ulcer based on Precede Model. A cross-sectional study with 120 subject patients, who were referred to Shahid Sadoghi Hospital of Yazd. The patients were selected by simple Random sampling and data were collected by researchers making questionnaire. The validity and reliability of the questionnaire was approved. The data collected were transferred directly into SPSS. For data analysis, correlations, T-test, One way - ANOVA were used. Results showed that there was a significant difference between the Quality of Life and Self-Management (p=0.05) and Quality of Life with Health Status (p=0.01). Pearson correlation showed that there was a significant correlation between the Quality of Life and Reinforcing factors (P=0.01). Totally, it was found that the health status, Self-Management, Predisposing and Enabling factors predicted 0.64 of the quality of life variance, among which, the Health Status was the strongest predictor (β=0.575). What should be taken into account is the cultural situation of Iran and the fact that the PRECEDE model is a model for planning intervention. It can be used as a framework for planning intervention in order to promote the quality of life of ulcer peptic patients in Iran.

  5. Linear Temporal Logic-based Mission Planning

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    Anil Kumar

    2016-06-01

    Full Text Available In this paper, we describe the Linear Temporal Logic-based reactive motion planning. We address the problem of motion planning for mobile robots, wherein the goal specification of planning is given in complex environments. The desired task specification may consist of complex behaviors of the robot, including specifications for environment constraints, need of task optimality, obstacle avoidance, rescue specifications, surveillance specifications, safety specifications, etc. We use Linear Temporal Logic to give a representation for such complex task specification and constraints. The specifications are used by a verification engine to judge the feasibility and suitability of plans. The planner gives a motion strategy as output. Finally a controller is used to generate the desired trajectory to achieve such a goal. The approach is tested using simulations on the LTLMoP mission planning tool, operating over the Robot Operating System. Simulation results generated using high level planners and low level controllers work simultaneously for mission planning and controlling the physical behavior of the robot.

  6. Effectiveness of a Training Program based in PRECEDE Model on Fruit and Vegetable Consumption among Female Students

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    Ali Khani Jeihooni

    2017-10-01

    Full Text Available Background Fruit and vegetable consumption increases students' health and growth and strengthens their mental activities. The present study aimed to investigates a training program based on PRECEDE model on fruit and vegetable consumption by female students in high schools of Fasa, Iran. Materials and Methods This is a quasi –experimental study. The research sample includes 100 female high school students in Fasa city, Fars Province, Iran, who were randomly assigned to two groups of control (n=50 and experimental (n=50 groups. Data collection instrument was a questionnaire that included items on demographic characteristics and the PERCEDE model components (knowledge, attitude, enabling and reinforcing factors and performance. Educational intervention for the experimental group was carried out in four sessions which each lasting 55 to 60 minutes, and subjects were followed for 2 months. The questionnaires were administered to both groups before and 3 months after the intervention. The collected data was analyzed by SPSS version 18.0 statistical software. Results The average performance score of experimental and control groups regarding fruits and vegetables consumption was 15.15±2.44 and 14.96±2.12 (before the intervention and 28.22±2.22 and 16.1±11.32 (after the intervention. Mean scores of predisposing (knowledge and attitude, reinforcing, and enabling factors showed a significant difference in the experimental group in comparison the control group (P

  7. A PRECEDE-PROCEED based educational intervention in quality of life of women-headed households in Iran.

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    Solhi, Mahnaz; Shabani Hamedan, Marziyeh; Salehi, Masoud

    2016-01-01

    Background: Women-headed households are more exposed to social damages than other women. Such condition remarkably influences the women's health-related life quality. The present study is aimed to investigate the effect of an educational intervention in quality of life of women-headed households under protection of Tehran Welfare Organization, in 2015. Methods: In this quasi-experimental study with control group, 180 women-headed households participated. Sampling method was random allocation. Data collection tools were Life Quality standard questionnaire (WHOQOL-BREF) and a researcher-made questionnaire about structures of ecological and educational diagnosis phase of PRECEDE-PROCEED model. Validity and reliability of the questionnaire approved in a primary study. Based on the results obtained from the primary study, the intervention was performed in the case group only. Participants were followed one and three months after intervention. Data were analyzed through SPSS v. 15 software using descriptive and analytical tests. Results: Before intervention no significant difference was observed among the mean scores of life quality, behavioral factors, and knowledge, enabling, and reinforcing factors in the two groups. But, one month and three months after intervention a significant difference was observed between the mean scores of these variables (in five instances pwomen-headed households' quality of life. The innovation of this study is using such intervention on quality of life in women-headed households for the first time.

  8. The effect of the training program on the quality of life in patients with asthma based on the Precede model in Ahvaz, Iran.

    Science.gov (United States)

    Nejad, Mina Motaghi; Nejad, Ghodratollah Shakeri; Tavakol, Heshmatollah; Cheraghi, Maria

    2017-06-01

    The aim of the study was to determine the effect of the training program based on the Precede model and its main components on improving the quality of life in patients with asthma. It was a randomized quasi-experimental study done on 120 patients with asthma who were referred to the Imam Khomeini hospital in Ahvaz who were selected using the convenience sampling method and were randomly divided into intervention and control groups. The data collection tool consisted of two questionnaires. The first questionnaire evaluated the quality of life in patients with asthma and the other one was developed by the researcher based on the structures of the Precede model. Training intervention was conducted during four sessions twice a week and each session was carried out for an hour based on the structures of the Precede model. In order to achieve the results, SPSS software, even t-test, and χ(2) were used. The results showed that after the training intervention in the experimental group, the mean scores of predisposing factors (p quality of life in two groups after the intervention (p quality of life of patients in the experimental group was improved after the training intervention. The design and implementation of the training program based on the Precede model can have a positive effect on the improvement of quality of life in patients with asthma.

  9. Precedent Phenomena in Quebecois Linguistic World View

    Directory of Open Access Journals (Sweden)

    Ксения Эдуардовна Болотина

    2016-12-01

    Full Text Available This article is devoted to the linguocultural analysis of precedent phenomena as parts of Quebecois’ cognitive base. Precedent phenomena being cultural facts are one of the key issues in modern linguistic and cognitive studies. By precedent phenomena we mean, according to Y.E. Prohorov, such entities when verbalized in discourse that refer to a certain cultural fact behind them. In the article the precedent phenomena such as precedent text, precedent situation, precedent utterance, and precedent name are analyzed. The main theses of the precedence theory given in the article (Y.N. Karaulov, Y.E. Prohorov, V.V. Krasnyh, D.B. Gudkov are at the heart of precedence studies on the basis of different languages. However, a complex analysis of precedent phenomena in the Quebec national variant of French is new to Russian linguistics. The study of precedent phenomena enables us to elicit features of their functioning in ethnospecific discourse and determine cultural dominants existing in Quebecois’ linguistic world view. Given the fact that the size of the article is limited, we undertooke the analysis of eight phenomena precedent of the bearers of Quebec linguoculture. The choice of phenomena is determined by the frequency of their use in discourse. The facts analyzed are of national character, i.e. known to all members of the linguocultural community. A certain cultural fact is at the very core of each precedent phenomenon given in the article. To get the whole picture we analysed historic, political, and cultural context connected to the precedent phenomena in question. The study enables us to elicit distinctive features that are at the core of each phenomenon. The results are backed with the supportive material drawn from analysis of different types of discourse. The analysis of precedent phenomena undertaken in this article allows us to reconstruct, to a certain extent, Quebec cultural space and is a stepping stone to the reconstruction of the

  10. Characterizing Gene Expressions Based on Their Temporal Observations

    Directory of Open Access Journals (Sweden)

    Jiuzhou Song

    2009-01-01

    Full Text Available Temporal gene expression data are of particular interest to researchers as they contain rich information in characterization of gene function and have been widely used in biomedical studies. However, extracting information and identifying efficient treatment effects without loss of temporal information are still in problem. In this paper, we propose a method of classifying temporal gene expression curves in which individual expression trajectory is modeled as longitudinal data with changeable variance and covariance structure. The method, mainly based on generalized mixed model, is illustrated by a dense temporal gene expression data in bacteria. We aimed at evaluating gene effects and treatments. The power and time points of measurements are also characterized via the longitudinal mixed model. The results indicated that the proposed methodology is promising for the analysis of temporal gene expression data, and that it could be generally applicable to other high-throughput temporal gene expression analyses.

  11. Towards Task-Based Temporal Extraction and Recognition

    NARCIS (Netherlands)

    Ahn, D.D.; Fissaha Adafre, S.; de Rijke, M.

    2005-01-01

    We seek to improve the robustness and portability of temporal information extraction systems by incorporating data-driven techniques. We present two sets of experiments pointing us in this direction. The first shows that machine-learning-based recognition of temporal expressions not only achieves

  12. The effect of the training program on the quality of life in patients with asthma based on the Precede model in Ahvaz, Iran

    Directory of Open Access Journals (Sweden)

    Mina Motaghi Nejad

    2017-05-01

    Full Text Available Aim: The aim of the study was to determine the effect of the training program based on the Precede model and its main components on improving the quality of life in patients with asthma. Material and methods: It was a randomized quasi-experimental study done on 120 patients with asthma who were referred to the Imam Khomeini hospital in Ahvaz who were selected using the convenience sampling method and were randomly divided into intervention and control groups. The data collection tool consisted of two questionnaires. The first questionnaire evaluated the quality of life in patients with asthma and the other one was developed by the researcher based on the structures of the Precede model. Training intervention was conducted during four sessions twice a week and each session was carried out for an hour based on the structures of the Precede model. In order to achieve the results, SPSS software, even t-test, and 2 were used. Results: The results showed that after the training intervention in the experimental group, the mean scores of predisposing factors (p < 0.001, enabling factors, reinforcing factors and behavioral factors were significantly increased (p < 0.001 as compared to the control group. A significant difference was observed in the mean scores of quality of life in two groups after the intervention (p < 0.001, and the quality of life of patients in the experimental group was improved after the training intervention. Conclusions : The design and implementation of the training program based on the Precede model can have a positive effect on the improvement of quality of life in patients with asthma.

  13. The Effect of Educational Intervention Based on PRECEDE-PROCEED Model on Promoting Traffic Safety Behaviors in Primary Schools Students of Tabriz in 2014

    Directory of Open Access Journals (Sweden)

    Saeed Omidi

    2016-03-01

    Full Text Available Background and Objectives: Pedestrian injuries are a public health problem and one of the major victims of road traffic injuries are children. Education is one of the most important strategies to solve traffic problems. To achieve effective results, education should be defined on the basis of theories and models. The aim of this study was to evaluate the effect of PRECEDE-PROCEED based intervention for promoting traffic safety behaviors in elementary schools students of Tabriz. Materials and Methods: This study was a randomized controlled trial. The sample included 75 elementary students who were randomly selected from two different schools. Data was collected using a questionnaire including the PRECEDE-PROCEED model constructs and demographic variables. Participants completed questionnaires before and one month after intervention. The intervention consisted of six sessions and was conducted in experimental group schools. The data were analyzed with fisher’s exact test, chi square, t-test and paired t-test, using SPSS-18 software. Results: The average age of participants was 10.11 ± 0.68 years. There was no significant differences in demographic variables between the two groups before the intervention (P>0.05. The findings showed that after the educational intervention, significant differences were observed in knowledge, attitude, enabling factors, reinforcing factors and behavior scores in the experimental group compared to the control group. Conclusions: An educational intervention based on the PRECEDE-PROCEED model could promote students’ traffic safety behaviors.

  14. Signs of dysregulated fibrinolysis precede the development of type 2 diabetes mellitus in a population-based study

    Directory of Open Access Journals (Sweden)

    Hernestål-Boman Jenny

    2012-12-01

    Full Text Available Abstract Background Diabetic patients experience stimulated coagulation and dysfibrinolysis, which is associated with an increased risk of cardiovascular events. This imbalance may precede the manifest diagnosis. We investigated whether elevated antigen levels of tissue plasminogen activator (tPA, plasminogen activator inhibitor-1 (PAI-1, the tPA/PAI-1 complex, or von Willebrand Factor (VWF precede type 2 diabetes mellitus (T2DM diagnosis, and whether this elevation occurs before increased fasting plasma glucose (FPG or 2-hour plasma glucose (2hPG in individuals who later develop T2DM. Methods We conducted a prospective incident case-referent study within the Västerbotten Intervention Programme. Cardiovascular risk factor data as well as FPG and 2hPG and blood samples for future research were collected at a baseline health examination between 1989 and 2000, (n= 28 736. During follow-up in January 2001, 157 cases had developed T2DM. Referents without T2DM were matched for sex, age, and year of participation (n=277. Subgroup analysis was performed for cases with normal baseline glucose levels (FPG Results After adjusting for BMI, family history of diabetes, physical activity, smoking, systolic blood pressure and levels of C-reactive protein and triglycerides, independent associations were found between incident T2DM and elevated levels of tPA (OR=1.54, 95% CI 1.06-2.23, PAI-1 (OR=1.61, 95% CI 1.14-2.28, and tPA/PAI-1 complex (OR=2.45, 95% CI 1.56-3.84. In participants with normal glucose levels, PAI-1 (OR=2.06, 95% CI 1.10 - 3.86 exhibited an independent relationship with incident T2DM after the adjustments. Conclusions Elevated levels of fibrinolytic variables precede the manifestation of T2DM after adjusting for metabolic and cardiovascular risk factors and can be detected several years before changes in glucose tolerance.

  15. Effects of educational intervention based on PRECEDE model on self care behaviors and control in patients with type 2 diabetes in 2012.

    Science.gov (United States)

    Dizaji, Mahboobeh Borhani; Taghdisi, Mohammad Hosein; Solhi, Mahnaz; Hoseini, Seyed Mojtaba; Shafieyan, Zahra; Qorbani, Mostafa; Mansourian, Morteza; Charkazi, Abdurrahman; Rezapoor, Aziz

    2014-01-01

    Diabetes is a chronic disease and its control requires essential change in patients' life style. The aim of this study was survey of effects of educational intervention based on PRECEDE Model on self care behaviors and control in patients with type 2 diabetes. This was a quasi-experimental study carried out in 78 patients with type 2 diabetes who have referred to Minoodasht clinic of diabetes. The educational program has been designed according to the PRECEDE Model. Prior to perform the educational intervention, the patients filled a questionnaire which was designed according to the structure of PRECEDE Model for type 2 diabetes patients. The diabetes education program was performed on three target groups (patients, their families and Health care personnel). After four weeks, the effects of the educational program have been evaluated through the same questionnaire. The findings were analyzed by SPSS version 16 and p-value less than 0.05 was taken as statistically significant. The mean age of participants was 49 years, 87.2% were married and 19.2% was illiterate. The rate of income of 44.9% was low. 66% had a family history of diabetes and 64% had been afflicted with diabetes more than 5 years. The Chi-square test showed a significant relationship between formation of a file in diabetes clinic and on-time presence to receive services and participation in the educational classes with the marital status variable. The results also showed that there is a significant relationship between observing food diet and job. The mean scores of knowledge, attitude, practice, reinforcing factors and enabling factors has increased after educational intervention. The Chi-square test shows a significant difference before and after of education intervention in stages of the model. The obtained results based on PRECEDE Model would support the positive effect of the educational intervention and its major elements (predisposing, enabling and reinforcing factors) on diabetes self

  16. Scrum and Temporal Distance-Based Global Software Development

    National Research Council Canada - National Science Library

    Asmaa Fowzi Alotaibi; M Rizwan Jameel Qureshi

    2014-01-01

    .... The last years has witnessed a significant increase in the adoption of Agile in GSD .This paper considers the issue by examining whether Scrum practices used in mitigation of temporal distance-based GSD coordination challenges...

  17. Precede-and-command revisited revisited

    NARCIS (Netherlands)

    Zwart, Cornelius

    2015-01-01

    Basing his argumentation on an analysis of condition C effects, Bruening (2014) proposes to replace the familiar notion of c-command underlying dependency relations with a precede-and-command condition, which defines dependency relations as precedence relations within a local domain (phase). In this

  18. STRAD Wheel: Web-Based Library for Visualizing Temporal Data.

    Science.gov (United States)

    Fernondez-Prieto, Diana; Naranjo-Valero, Carol; Hernandez, Jose Tiberio; Hagen, Hans

    2017-01-01

    Recent advances in web development, including the introduction of HTML5, have opened a door for visualization researchers and developers to quickly access larger audiences worldwide. Open source libraries for the creation of interactive visualizations are becoming more specialized but also modular, which makes them easy to incorporate in domain-specific applications. In this context, the authors developed STRAD (Spatio-Temporal-Radar) Wheel, a web-based library that focuses on the visualization and interactive query of temporal data in a compact view with multiple temporal granularities. This article includes two application examples in urban planning to help illustrate the proposed visualization's use in practice.

  19. Visually lossless coding based on temporal masking in human vision

    Science.gov (United States)

    Adzic, Velibor; Hock, Howard S.; Kalva, Hari

    2014-02-01

    This paper presents a method for perceptual video compression that exploits the phenomenon of backward temporal masking. We present an overview of visual temporal masking and discuss models to identify portions of a video sequences masked due to this phenomenon exhibited by the human visual system. A quantization control model based on the psychophysical model of backward visual temporal masking was developed. We conducted two types of subjective evaluations and demonstrated that the proposed method up to 10% bitrate savings on top of state of the art encoder with visually identical video. The proposed methods were evaluated using HEVC encoder.

  20. Applying an Educational-participatory Program based on the PRECEDE Model for Promoting Self-esteem and Mental Health of Students in Iran.

    Science.gov (United States)

    Moshki, Mahdi; Atarodi, B Alireza; Moslem, Alireza; Taheri, Mahdokht

    2012-04-01

    The students' vulnerability to different problems can have an impact on their mental health. Regarding the lack of evidence on the effectiveness of interventional programs based on health education planning models in this area in developing countries, an educational-participatory program based on the PRECEDE model was used, to promote the medical science students' self-esteem and mental health status, in Iran. In this experimental study, 154 students from the universities of medical sciences in the north east of Iran were selected by stratified random sampling method. Then, they were randomly assigned to two groups of case and control. The questionnaires, including the enabling, reinforcing, and predisposing factors, the Rosenberg self-esteem scale, and the GHQ-28 were used for data collection. Then, an intervention plan, including focus group discussions and training of selected life skills, based on the PRECEDE model, was conducted for the case group. The predisposing, reinforcing, and enabling factors, and the self-esteem and mental health of the students showed a significant difference between the case and control groups. The Pearson correlation coefficient showed that there was a correlation between mental health and knowledge (P =0.008), between self-esteem and knowledge (P =0.02), self-esteem and attitude (P =0.01), and mental health and attitude (P = 0.03). Health promotion planning by using life skills training based on the PRECEDE model can result in participation and empowerment, in order to promote the self-esteem and mental health of the students.

  1. Image-based temporal alignment of echocardiographic sequences

    Science.gov (United States)

    Danudibroto, Adriyana; Bersvendsen, Jørn; Mirea, Oana; Gerard, Olivier; D'hooge, Jan; Samset, Eigil

    2016-04-01

    Temporal alignment of echocardiographic sequences enables fair comparisons of multiple cardiac sequences by showing corresponding frames at given time points in the cardiac cycle. It is also essential for spatial registration of echo volumes where several acquisitions are combined for enhancement of image quality or forming larger field of view. In this study, three different image-based temporal alignment methods were investigated. First, a method based on dynamic time warping (DTW). Second, a spline-based method that optimized the similarity between temporal characteristic curves of the cardiac cycle using 1D cubic B-spline interpolation. Third, a method based on the spline-based method with piecewise modification. These methods were tested on in-vivo data sets of 19 echo sequences. For each sequence, the mitral valve opening (MVO) time was manually annotated. The results showed that the average MVO timing error for all methods are well under the time resolution of the sequences.

  2. The Home Care Crew Scheduling Problem: Preference-based visit clustering and temporal dependencies

    DEFF Research Database (Denmark)

    Rasmussen, Matias Sevel; Justesen, Tor Fog; Dohn, Anders Høeg

    2012-01-01

    branch-and-price solution algorithm, as this method has previously given solid results for classical vehicle routing problems. Temporal dependencies are modelled as generalised precedence constraints and enforced through the branching. We introduce a novel visit clustering approach based on the soft...... preference constraints. The algorithm is tested both on real-life problem instances and on generated test instances inspired by realistic settings. The use of the specialised branching scheme on real-life problems is novel. The visit clustering decreases run times significantly, and only gives a loss...... of quality for few instances. Furthermore, the visit clustering allows us to find solutions to larger problem instances, which cannot be solved to optimality....

  3. FPGA BASED HARDWARE KEY FOR TEMPORAL ENCRYPTION

    Directory of Open Access Journals (Sweden)

    B. Lakshmi

    2010-09-01

    Full Text Available In this paper, a novel encryption scheme with time based key technique on an FPGA is presented. Time based key technique ensures right key to be entered at right time and hence, vulnerability of encryption through brute force attack is eliminated. Presently available encryption systems, suffer from Brute force attack and in such a case, the time taken for breaking a code depends on the system used for cryptanalysis. The proposed scheme provides an effective method in which the time is taken as the second dimension of the key so that the same system can defend against brute force attack more vigorously. In the proposed scheme, the key is rotated continuously and four bits are drawn from the key with their concatenated value representing the delay the system has to wait. This forms the time based key concept. Also the key based function selection from a pool of functions enhances the confusion and diffusion to defend against linear and differential attacks while the time factor inclusion makes the brute force attack nearly impossible. In the proposed scheme, the key scheduler is implemented on FPGA that generates the right key at right time intervals which is then connected to a NIOS – II processor (a virtual microcontroller which is brought out from Altera FPGA that communicates with the keys to the personal computer through JTAG (Joint Test Action Group communication and the computer is used to perform encryption (or decryption. In this case the FPGA serves as hardware key (dongle for data encryption (or decryption.

  4. WORD BASED TAMIL SPEECH RECOGNITION USING TEMPORAL FEATURE BASED SEGMENTATION

    Directory of Open Access Journals (Sweden)

    A. Akila

    2015-05-01

    Full Text Available Speech recognition system requires segmentation of speech waveform into fundamental acoustic units. Segmentation is a process of decomposing the speech signal into smaller units. Speech segmentation could be done using wavelet, fuzzy methods, Artificial Neural Networks and Hidden Markov Model. Speech segmentation is a process of breaking continuous stream of sound into some basic units like words, phonemes or syllable that could be recognized. Segmentation could be used to distinguish different types of audio signals from large amount of audio data, often referred as audio classification. The speech segmentation can be divided into two categories based on whether the algorithm uses previous knowledge of data to process the speech. The categories are blind segmentation and aided segmentation.The major issues with the connected speech recognition algorithms were the vocabulary size will be larger with variation in the combination of words in the connected speech and the complexity of the algorithm is more to find the best match for the given test pattern. To overcome these issues, the connected speech has to be segmented into words using the attributes of speech. A methodology using the temporal feature Short Term Energy was proposed and compared with an existing algorithm called Dynamic Thresholding segmentation algorithm which uses spectrogram image of the connected speech for segmentation.

  5. High Body Mass Index in Adolescent Girls Precedes Psoriasis Hospitalization

    DEFF Research Database (Denmark)

    Bryld, L.E.; Sørensen, T.I.A.; Andersen, Klaus Kaae

    2010-01-01

    for being overweight in adulthood. The study cohort was based on the Copenhagen School Health Records Register, birth years 1930 to 1984 (309,152 schoolchildren). Cases were found through the Danish National Patient Register for the period 1977 to 2001. A total of 1074 (0.36%) of the schoolchildren were......Psoriasis is associated with being overweight, but the temporal relationship is not known. This historical cohort study tested whether severe psoriasis resulting in hospitalization in adulthood was preceded by excess increase in age-adjusted body mass index, a known risk factor in childhood...

  6. Spatio-Temporal Data Mining for Location-Based Services

    DEFF Research Database (Denmark)

    Gidofalvi, Gyozo

    . The objectives of the presented thesis are three-fold. First, to extend popular data mining methods to the spatio-temporal domain. Second, to demonstrate the usefulness of the extended methods and the derived knowledge in promising LBS examples. Finally, to eliminate privacy concerns in connection with spatio......-temporal data mining by devising systems for privacy-preserving location data collection and mining.......Location-Based Services (LBS) are continuously gaining popularity. Innovative LBSes integrate knowledge about the users into the service. Such knowledge can be derived by analyzing the location data of users. Such data contain two unique dimensions, space and time, which need to be analyzed...

  7. Effect of Educational Program, Based on PRECEDE and Trans-Theoretical Models, on Preventing Decline in Regular Physical Activity and Improving it among Students.

    Science.gov (United States)

    Rostami-Moez, Masomeh; Rezapur-Shahkolai, Forouzan; Hazavehei, Seyyed Mohammad-Mahdi; Karami, Manoochehr; Karimi-Shahanjarini, Akram; Nazem, Farzad

    2017-04-10

    Adolescents especially middle school girls do not follow 60 min of regular physical activity (RPA), recommended by WHO, and endure physical activity decline. Using theory-based interventional program, considering the age of decline in RPA, seems to be effective. The aim of this study was to determine the effects of educational program, based on PRECEDE and Trans-Theoretical models, on preventing decline in RPA and improving it among 7th grade girl students. Randomized controlled trial. This study was conducted on 7th grade girl students in Hamadan, west of Iran from 2015-16. Participants were divided into intervention (N=179) and control (N=165) groups by random assignment. Physical activity questionnaire for adolescents and the model-based questionnaire were used before and after intervention. Intervention included two months education and six months follow up. The effects of intervention were determined by statistical test and analysis of covariance using SPSS version 16. The higher change in the mean scores was observed in self-efficacy (0.86), counter condition (0.66) and helping relationship (0.57) in the intervention group (P≤0.001). In addition, a significant difference (P ≤0.001) was observed between the two groups 6 months after the intervention in all constructs of model. The mean score of doing physical activity in the intervention group increased from 2.50 to 3.17 that it was differed significantly from the control group (P≤0.001).  CONCLUSIONS: School based intervention using PRECEDE and Trans-Theoretical models might prevent girl students' RPA decline and improve their RPA.

  8. Temporal community detection based on symmetric nonnegative matrix factorization

    Science.gov (United States)

    Jiao, Pengfei; Lyu, Haodong; Li, Xiaoming; Yu, Wei; Wang, Wenjun

    2017-05-01

    To understand time-evolving networks, researchers should not only concentrate on the community structures, an essential property of complex networks, in each snapshot, but also study the internal evolution of the entire networks. Temporal communities provide insights into such mechanism, i.e., how the communities emerge, expand, shrink, merge, split and decay over time. Based on the symmetric nonnegative matrix factorization (SNMF), we present a dynamic model to detect temporal communities, which not only could find a well community structure in a given snapshot but also demands the results bear some similarity to the partition obtained from the previous snapshot. Moreover, our method can handle the situation that of the number of community changes in the networks. Also, a gradient descent algorithm is proposed to optimize the objective function of the model. Experimental results on both the synthetic and real-world networks indicate that our method outperforms the state-of-art methods for temporal community detection.

  9. A randomized controlled trial of telephone-mentoring with home-based walking preceding rehabilitation in COPD

    Directory of Open Access Journals (Sweden)

    Cameron-Tucker HL

    2016-08-01

    Full Text Available Helen Laura Cameron-Tucker,1 Richard Wood-Baker,1 Lyn Joseph,1 Julia A Walters,1 Natalie Schüz,2 E Haydn Walters1 1Centre of Research Excellence for Chronic Respiratory Disease and Lung Aging, School of Medicine, 2School of Health Sciences, Faculty of Health, University of Tasmania, Hobart, Tasmania, Australia Purpose: With the limited reach of pulmonary rehabilitation (PR and low levels of daily physical activity in chronic obstructive pulmonary disease (COPD, a need exists to increase daily exercise. This study evaluated telephone health-mentoring targeting home-based walking (tele-rehab compared to usual waiting time (usual care followed by group PR. Patients and methods: People with COPD were randomized to tele-rehab (intervention or usual care (controls. Tele-rehab delivered by trained nurse health-mentors supported participants’ home-based walking over 8–12 weeks. PR, delivered to both groups simultaneously, included 8 weeks of once-weekly education and self-management skills, with separate supervised exercise. Data were collected at three time-points: baseline (TP1, before (TP2, and after (TP3 PR. The primary outcome was change in physical capacity measured by 6-minute walk distance (6MWD with two tests performed at each time-point. Secondary outcomes included changes in self-reported home-based walking, health-related quality of life, and health behaviors. Results: Of 65 recruits, 25 withdrew before completing PR. Forty attended a median of 6 (4 education sessions. Seventeen attended supervised exercise (5±2 sessions. Between TP1 and TP2, there was a statistically significant increase in the median 6MWD of 12 (39.1 m in controls, but no change in the tele-rehab group. There were no significant changes in 6MWD between other time-points or groups, or significant change in any secondary outcomes. Participants attending supervised exercise showed a nonsignificant improvement in 6MWD, 12.3 (71 m, while others showed no change, 0 (33 m

  10. The effect of an educational program based on the PRECEDE Model on the level of academic consultants' ability and students' satisfaction

    Directory of Open Access Journals (Sweden)

    Hazavehei SMM

    2003-07-01

    Full Text Available Background: Universities have important responsibilities to prevent physical, emotional, social and academic problems during the course of their study. To achieve this goal, it is necessary that universities offer effective academic advising services to the students. Purpose: To investigate the effectiveness of programs offered for developing academic consultants (AC ability by assessing students’ satisfaction with the consultation they recieve. Methods: From a total of 90 ACs and 2,500 students in the Hamadan University of Medical Sciences, 72 AC and 445 students from four colleges (Medicine, Health Sciences, Dentistry, Nursing and Midwifery voluntarily participated in the pretest. 87 ACs were randomly assigned into two groups (Group Bf participated in a workshop designed based on PRECEDE model; Group Cf was offered material relevant to academic consultation. According to the AC groups, the students were divided into groupBs(n=363; their AC have participated in workshop, group Cs (n=408; their AC received Educational Material, and groupDs (n= 190; the student have no active AC. Data collection was conducted by questionnaires, pre-test and post-test (after one academic semester prior to the intervention. Results: Mean scores of knowledge (M=14.77, SD=3.01 (especially in the College of Medicine and Dentistry and attitude (M=61.79, SD=5.78 of AC about offering effective academic advising to the students was improved significantly in both intervention groups, but this effect was more pronounced in group Bf compared with group Cf (M= 1 1.54,SD=2.76; M=59.23,SD=8.6 (n=44, and group Af (the pre-test group (M=10.67,SD=4.2; M=57.2,SD=1 1.6. Students in group Bf significantly were more satisfied with consultation they received and more willing to use consultation services of their ACs. Conclusion: The PRECEDE model's educational workshop program was more effective in modifying the AC ability in offering effective academic advising, guiding, and

  11. Sex of preceding sibling and anthropometrics of subsequent offspring at birth and in young adulthood: a population-based study in Sweden.

    Science.gov (United States)

    Jelenkovic, Aline; Silventoinen, Karri; Tynelius, Per; Helle, Samuli; Rasmussen, Finn

    2014-08-01

    In many mammal species with sexual dimorphism producing sons is energetically more demanding to the mother than producing daughters. Although some studies in humans have suggested that offspring born after a brother have a smaller birth weight and adult height when compared with those born after a sister, little is known about this intergenerational cost of producing sons. We aimed to study whether the sex of preceding sibling is associated with anthropometrics of the subsequent child at birth and in young adulthood. This population-based study was carried out on two data sets derived from the Swedish registers. Information on birth weight and length was obtained for 752,723 children of both sexes. Adult weight, height and muscle strength were available for 506,326 men. Multiple linear regression analyses showed that boys and girls born after a brother were, respectively, 18 and 9 g lighter and 0.08 and 0.03 cm (P birth than those born after a sister. Adjustment for gestational age decreased the magnitude of the associations [10 g and 0.04 cm (P birth weight and length of individuals born after a brother was due to a shorter gestation. In young adulthood, men with a preceding brother showed 0.16 kg more in weight, 0.3% higher body mass index (P < 0.001) and a trend towards reduced height and muscle strength. Our results suggest that even though the sex of the previous child is associated with the anthropometrics of the subsequent child, the effect sizes are very small questioning whether this mechanism has adaptive value in contemporary humans. © 2014 Wiley Periodicals, Inc.

  12. An advection-based model to increase the temporal resolution of PIV time series

    Energy Technology Data Exchange (ETDEWEB)

    Scarano, Fulvio; Moore, Peter [TU Delft, Aerospace Engineering Department, Delft (Netherlands)

    2012-04-15

    A numerical implementation of the advection equation is proposed to increase the temporal resolution of PIV time series. The method is based on the principle that velocity fluctuations are transported passively, similar to Taylor's hypothesis of frozen turbulence. In the present work, the advection model is extended to unsteady three-dimensional flows. The main objective of the method is that of lowering the requirement on the PIV repetition rate from the Eulerian frequency toward the Lagrangian one. The local trajectory of the fluid parcel is obtained by forward projection of the instantaneous velocity at the preceding time instant and backward projection from the subsequent time step. The trajectories are approximated by the instantaneous streamlines, which yields accurate results when the amplitude of velocity fluctuations is small with respect to the convective motion. The verification is performed with two experiments conducted at temporal resolutions significantly higher than that dictated by Nyquist criterion. The flow past the trailing edge of a NACA0012 airfoil closely approximates frozen turbulence, where the largest ratio between the Lagrangian and Eulerian temporal scales is expected. An order of magnitude reduction of the needed acquisition frequency is demonstrated by the velocity spectra of super-sampled series. The application to three-dimensional data is made with time-resolved tomographic PIV measurements of a transitional jet. Here, the 3D advection equation is implemented to estimate the fluid trajectories. The reduction in the minimum sampling rate by the use of super-sampling in this case is less, due to the fact that vortices occurring in the jet shear layer are not well approximated by sole advection at large time separation. Both cases reveal that the current requirements for time-resolved PIV experiments can be revised when information is poured from space to time. An additional favorable effect is observed by the analysis in the

  13. An advection-based model to increase the temporal resolution of PIV time series.

    Science.gov (United States)

    Scarano, Fulvio; Moore, Peter

    A numerical implementation of the advection equation is proposed to increase the temporal resolution of PIV time series. The method is based on the principle that velocity fluctuations are transported passively, similar to Taylor's hypothesis of frozen turbulence. In the present work, the advection model is extended to unsteady three-dimensional flows. The main objective of the method is that of lowering the requirement on the PIV repetition rate from the Eulerian frequency toward the Lagrangian one. The local trajectory of the fluid parcel is obtained by forward projection of the instantaneous velocity at the preceding time instant and backward projection from the subsequent time step. The trajectories are approximated by the instantaneous streamlines, which yields accurate results when the amplitude of velocity fluctuations is small with respect to the convective motion. The verification is performed with two experiments conducted at temporal resolutions significantly higher than that dictated by Nyquist criterion. The flow past the trailing edge of a NACA0012 airfoil closely approximates frozen turbulence, where the largest ratio between the Lagrangian and Eulerian temporal scales is expected. An order of magnitude reduction of the needed acquisition frequency is demonstrated by the velocity spectra of super-sampled series. The application to three-dimensional data is made with time-resolved tomographic PIV measurements of a transitional jet. Here, the 3D advection equation is implemented to estimate the fluid trajectories. The reduction in the minimum sampling rate by the use of super-sampling in this case is less, due to the fact that vortices occurring in the jet shear layer are not well approximated by sole advection at large time separation. Both cases reveal that the current requirements for time-resolved PIV experiments can be revised when information is poured from space to time. An additional favorable effect is observed by the analysis in the frequency

  14. Wavefront sensorless adaptive optics temporal focusing-based multiphoton microscopy

    Science.gov (United States)

    Chang, Chia-Yuan; Cheng, Li-Chung; Su, Hung-Wei; Hu, Yvonne Yuling; Cho, Keng-Chi; Yen, Wei-Chung; Xu, Chris; Dong, Chen Yuan; Chen, Shean-Jen

    2014-01-01

    Temporal profile distortions reduce excitation efficiency and image quality in temporal focusing-based multiphoton microscopy. In order to compensate the distortions, a wavefront sensorless adaptive optics system (AOS) was integrated into the microscope. The feedback control signal of the AOS was acquired from local image intensity maximization via a hill-climbing algorithm. The control signal was then utilized to drive a deformable mirror in such a way as to eliminate the distortions. With the AOS correction, not only is the axial excitation symmetrically refocused, but the axial resolution with full two-photon excited fluorescence (TPEF) intensity is also maintained. Hence, the contrast of the TPEF image of a R6G-doped PMMA thin film is enhanced along with a 3.7-fold increase in intensity. Furthermore, the TPEF image quality of 1μm fluorescent beads sealed in agarose gel at different depths is improved. PMID:24940539

  15. Temporal and Location Based RFID Event Data Management and Processing

    Science.gov (United States)

    Wang, Fusheng; Liu, Peiya

    Advance of sensor and RFID technology provides significant new power for humans to sense, understand and manage the world. RFID provides fast data collection with precise identification of objects with unique IDs without line of sight, thus it can be used for identifying, locating, tracking and monitoring physical objects. Despite these benefits, RFID poses many challenges for data processing and management. RFID data are temporal and history oriented, multi-dimensional, and carrying implicit semantics. Moreover, RFID applications are heterogeneous. RFID data management or data warehouse systems need to support generic and expressive data modeling for tracking and monitoring physical objects, and provide automated data interpretation and processing. We develop a powerful temporal and location oriented data model for modeling and queryingRFID data, and a declarative event and rule based framework for automated complex RFID event processing. The approach is general and can be easily adapted for different RFID-enabled applications, thus significantly reduces the cost of RFID data integration.

  16. Gait recognition using spatio-temporal silhouette-based features

    Science.gov (United States)

    Sabir, Azhin; Al-jawad, Naseer; Jassim, Sabah

    2013-05-01

    This paper presents a new algorithm for human gait recognition based on Spatio-temporal body biometric features using wavelet transforms. The proposed algorithm extracts the Gait cycle depending on the width of boundary box from a sequence of Silhouette images. Gait recognition is based on feature level fusion of three feature vectors: the gait spatio-temporal feature represented by the distances between (feet, knees, hands, shoulders, and height); binary difference between consecutive frames of the silhouette for each leg detected separately based on hamming distance; a vector of statistical parameters captured from the wavelet low frequency domain. The fused feature vector is subjected to dimension reduction using linear discriminate analysis. The Nearest Neighbour with a certain threshold used for classification. The threshold is obtained by experiment from a set of data captured from the CASIA database. We shall demonstrate that our method provides a non-traditional identification based on certain threshold to classify the outsider members as non-classified members.

  17. [Clinical classification of ALS patients based on the total course of ALS--proposal of respiratory motor paralysis-preceded type and its significance].

    Science.gov (United States)

    Hayashi, H; Kato, S; Shimizu, T; Kawada, A

    1997-05-01

    Since the motor paralysis occurs in all motor systems in ALS, the clinicopathological findings and care of the patients living beyond the development of respiratory failure must be considered. We have divided the efferent motor systems into four groups, i.e., limb, bulbar, respiratory, and external ocular. In this study, 37 ALS patients were followed for more than two years with respirator, and the onset of motor paralysis in all four systems was observed in each patient. First, we classified the patients into three groups according to the number of paralyzed motor systems observed within six months from the onset of the first motor paralysis, and we discuss the patient's prognosis after the first motor paralysis. Twenty-one patients with paralysis of the respiratory motor system alone were categorized as respiratory paralysis-preceded type ALS (R-type ALS), four patients with paralysis of the bulbar motor system alone as bulbar paralysis-preceded type ALS (B-type ALS), and 12 patients with simultaneous paralysis of two or more motor systems as combined motor system paralysis type ALS (C-type ALS). The results showed that the prognosis of R-type ALS is slow progression and that of C-type ALS, rapid progression. Next, we investigated the time of occurrence of the first motor paralysis of the four motor systems in 37 patients, and we discuss the most vulnerable motor functions in ALS, i.e., the initial clinical presentations in ALS. The most frequent first motor paralysis was of the respiratory motor system, and the initial clinical manifestations in ALS were impairment of fine discriminating voluntary respiratory and limb motor functions. These findings could be explained by the rule of ALS involvements, according to which onto-genetically newer motor functions are lost earlier than the older ones. Based on the findings in this study, we concluded that ALS initially involves the ontogenetically new motor functions in "the first system" proposed by G. Holstege, whose

  18. Information Security Scheme Based on Computational Temporal Ghost Imaging.

    Science.gov (United States)

    Jiang, Shan; Wang, Yurong; Long, Tao; Meng, Xiangfeng; Yang, Xiulun; Shu, Rong; Sun, Baoqing

    2017-08-09

    An information security scheme based on computational temporal ghost imaging is proposed. A sequence of independent 2D random binary patterns are used as encryption key to multiply with the 1D data stream. The cipher text is obtained by summing the weighted encryption key. The decryption process can be realized by correlation measurement between the encrypted information and the encryption key. Due to the instinct high-level randomness of the key, the security of this method is greatly guaranteed. The feasibility of this method and robustness against both occlusion and additional noise attacks are discussed with simulation, respectively.

  19. Effects of a self-management asthma educational program in Taiwan based on PRECEDE-PROCEED model for parents with asthmatic children.

    Science.gov (United States)

    Chiang, Li-Chi; Huang, Jing-Long; Yeh, Kuo-Wei; Lu, Chang-Ming

    2004-04-01

    This study was conducted to evaluate the comparative effectiveness of two different asthma educational programs. One was self-management asthma education based on the PRECEDE-PROCEED model to change the influential factors based on a previous need assessment study in Taiwan. The other consisted of regular outpatient asthma education. The purposes were: 1) to compare differences in the asthma knowledge, self-efficacy, perceived effectiveness, children's cooperation, doctor-patient communication, and self-management behaviors in the experimental and control groups before education, and 2 weeks, 3 months, and 6 months after education; and 2) to compare differences in drug use, medication utilization, asthma severity, signs/symptoms of asthma, school absenteeism, and exercise ability before education, and 2 weeks, 3 months, and 6 months after education. Parents of asthmatic children were recruited from among outpatients of Chang Gung Children's Hospital, Taoyuan, Taiwan. They were grouped by registration number: those with even numbers were assigned to the experimental group, and those with odd numbers were assigned to the control group. Measurements were collected four times from all parents by means of a questionnaire and chart review. The General Linear Model: Repeat Measurement was used to compare variance differences. The following results were found. 1) Asthma knowledge, self-efficacy, perceived effectiveness, children's cooperation, and self-management behaviors significantly improved after the self-management asthma educational program based on PRECEDE-PROCEED. Except for perceived effectiveness, all variables still had good effectiveness after 6 months of follow-up. The experimental group was better than the control group in knowledge, children's cooperation, and self-management behaviors at the 3-month follow up, as well as in knowledge and children's cooperation at the 6-month follow-up. 2) In both the experimental and control groups, the educational program

  20. YAG:Nd scanning laser with intracavity PLZT-based spatio-temporal light modulator

    Science.gov (United States)

    Alekseev, V. N.; Kotylev, V. N.; Liber, V. I.

    2003-08-01

    We report advancements in electrically controlled scanning of the direction of laser radiation preceded in 1-3 with application to the YAG:Nd and Cu vapor lasers its key specifications determined by intracavity PLZT spatio-temporal light modulator (STLM) located within a linear conjugate cavity. In the present work the results of an experimental research into the radiation characteristics of the laser with a polarizing output of radiation from the resonator are given. One of the lenses of the conjugate laser resonator is a cylindrical lens. Due to optical relief of the STLM and use of a cylindrical lens the output energy of a lasing pulse is increased signifciantly. The laser radiation scans along the vertical coordinate and is specified by packets of 10-20 pulses with the 15-50 kHz repetition frequency in a packet, up to 10 mJ energy, and the 150-250 ns pulse duration. The laser is operating in the 5-10Hz pulse repetition regime with 1 millisecond duration pumping pulse. Movement of the article during marking provides the second coordiate. STLM based scanning laser is an effective alternative both to jet markers for articles moving on a conveyor belt and the existing laser markers with optomechanical scanning. Capabilities to enhance overall performance of the scanning laser are discussed and samples of markings obtained on different materials demonstrated.

  1. Fuzzy temporal logic based railway passenger flow forecast model.

    Science.gov (United States)

    Dou, Fei; Jia, Limin; Wang, Li; Xu, Jie; Huang, Yakun

    2014-01-01

    Passenger flow forecast is of essential importance to the organization of railway transportation and is one of the most important basics for the decision-making on transportation pattern and train operation planning. Passenger flow of high-speed railway features the quasi-periodic variations in a short time and complex nonlinear fluctuation because of existence of many influencing factors. In this study, a fuzzy temporal logic based passenger flow forecast model (FTLPFFM) is presented based on fuzzy logic relationship recognition techniques that predicts the short-term passenger flow for high-speed railway, and the forecast accuracy is also significantly improved. An applied case that uses the real-world data illustrates the precision and accuracy of FTLPFFM. For this applied case, the proposed model performs better than the k-nearest neighbor (KNN) and autoregressive integrated moving average (ARIMA) models.

  2. Innovations in individual feature history management - The significance of feature-based temporal model

    Science.gov (United States)

    Choi, J.; Seong, J.C.; Kim, B.; Usery, E.L.

    2008-01-01

    A feature relies on three dimensions (space, theme, and time) for its representation. Even though spatiotemporal models have been proposed, they have principally focused on the spatial changes of a feature. In this paper, a feature-based temporal model is proposed to represent the changes of both space and theme independently. The proposed model modifies the ISO's temporal schema and adds new explicit temporal relationship structure that stores temporal topological relationship with the ISO's temporal primitives of a feature in order to keep track feature history. The explicit temporal relationship can enhance query performance on feature history by removing topological comparison during query process. Further, a prototype system has been developed to test a proposed feature-based temporal model by querying land parcel history in Athens, Georgia. The result of temporal query on individual feature history shows the efficiency of the explicit temporal relationship structure. ?? Springer Science+Business Media, LLC 2007.

  3. A Temporal Fuzzy Logic Formalism for Knowledge Based Systems

    Directory of Open Access Journals (Sweden)

    Vasile MAZILESCU

    2012-11-01

    Full Text Available This paper shows that the influence of knowledge on new forms of work organisation can be described as mutual relationships. Different changes in work organisation also have a strong influence on the increasing importance of knowledge of different individual and collective actors in working situations. After that, we characterize a piece of basic formal system, an Extended Fuzzy Logic System (EFLS with temporal attributes, to conceptualize future DKMSs based on human imprecise for distributed just in time decisions. The approximate reasoning is perceived as a derivation of new formulas with the corresponding temporal attributes, within a fuzzy theory defined by the fuzzy set of special axioms. In a management application, the reasoning is evolutionary because of unexpected events which may change the state of the DKMS. In this kind of situations it is necessary to elaborate certain mechanisms in order to maintain the coherence of the obtained conclusions, to figure out their degree of reliability and the time domain for which these are true. These last aspects stand as possible further directions of development at a basic logic level for future technologies that must automate knowledge organizational processes.

  4. EIGENVECTOR-BASED CENTRALITY MEASURES FOR TEMPORAL NETWORKS*

    Science.gov (United States)

    TAYLOR, DANE; MYERS, SEAN A.; CLAUSET, AARON; PORTER, MASON A.; MUCHA, PETER J.

    2017-01-01

    Numerous centrality measures have been developed to quantify the importances of nodes in time-independent networks, and many of them can be expressed as the leading eigenvector of some matrix. With the increasing availability of network data that changes in time, it is important to extend such eigenvector-based centrality measures to time-dependent networks. In this paper, we introduce a principled generalization of network centrality measures that is valid for any eigenvector-based centrality. We consider a temporal network with N nodes as a sequence of T layers that describe the network during different time windows, and we couple centrality matrices for the layers into a supra-centrality matrix of size NT × NT whose dominant eigenvector gives the centrality of each node i at each time t. We refer to this eigenvector and its components as a joint centrality, as it reflects the importances of both the node i and the time layer t. We also introduce the concepts of marginal and conditional centralities, which facilitate the study of centrality trajectories over time. We find that the strength of coupling between layers is important for determining multiscale properties of centrality, such as localization phenomena and the time scale of centrality changes. In the strong-coupling regime, we derive expressions for time-averaged centralities, which are given by the zeroth-order terms of a singular perturbation expansion. We also study first-order terms to obtain first-order-mover scores, which concisely describe the magnitude of nodes’ centrality changes over time. As examples, we apply our method to three empirical temporal networks: the United States Ph.D. exchange in mathematics, costarring relationships among top-billed actors during the Golden Age of Hollywood, and citations of decisions from the United States Supreme Court. PMID:29046619

  5. EIGENVECTOR-BASED CENTRALITY MEASURES FOR TEMPORAL NETWORKS.

    Science.gov (United States)

    Taylor, Dane; Myers, Sean A; Clauset, Aaron; Porter, Mason A; Mucha, Peter J

    2017-01-01

    Numerous centrality measures have been developed to quantify the importances of nodes in time-independent networks, and many of them can be expressed as the leading eigenvector of some matrix. With the increasing availability of network data that changes in time, it is important to extend such eigenvector-based centrality measures to time-dependent networks. In this paper, we introduce a principled generalization of network centrality measures that is valid for any eigenvector-based centrality. We consider a temporal network with N nodes as a sequence of T layers that describe the network during different time windows, and we couple centrality matrices for the layers into a supra-centrality matrix of size NT × NT whose dominant eigenvector gives the centrality of each node i at each time t. We refer to this eigenvector and its components as a joint centrality, as it reflects the importances of both the node i and the time layer t. We also introduce the concepts of marginal and conditional centralities, which facilitate the study of centrality trajectories over time. We find that the strength of coupling between layers is important for determining multiscale properties of centrality, such as localization phenomena and the time scale of centrality changes. In the strong-coupling regime, we derive expressions for time-averaged centralities, which are given by the zeroth-order terms of a singular perturbation expansion. We also study first-order terms to obtain first-order-mover scores, which concisely describe the magnitude of nodes' centrality changes over time. As examples, we apply our method to three empirical temporal networks: the United States Ph.D. exchange in mathematics, costarring relationships among top-billed actors during the Golden Age of Hollywood, and citations of decisions from the United States Supreme Court.

  6. Continuation Passing Combinators for Parsing Precedence Grammars

    OpenAIRE

    Hill, Steve

    1994-01-01

    We describe a scheme for constructing parsers for precedence grammars based on the combinators described by Hutton. The new combinators provide a robust method for building parsers and help avoid the possibility of a non-terminating parser. Efficiency is improved via an optimisation to the grammar. A number of approaches to the problem are described - the most elegant and efficient method is based on continuation passing. A parser for the expression part of the C programming language is prese...

  7. Unrecorded Accidents Detection on Highways Based on Temporal Data Mining

    Directory of Open Access Journals (Sweden)

    Shi An

    2014-01-01

    Full Text Available Automatic traffic accident detection, especially not recorded by traffic police, is crucial to accident black spots identification and traffic safety. A new method of detecting traffic accidents is proposed based on temporal data mining, which can identify the unknown and unrecorded accidents by traffic police. Time series model was constructed using ternary numbers to reflect the state of traffic flow based on cell transmission model. In order to deal with the aftereffects of linear drift between time series and to reduce the computational cost, discrete Fourier transform was implemented to turn time series from time domain to frequency domain. The pattern of the time series when an accident happened could be recognized using the historical crash data. Then taking Euclidean distance as the similarity evaluation function, similarity data mining of the transformed time series was carried out. If the result was less than the given threshold, the two time series were similar and an accident happened probably. A numerical example was carried out and the results verified the effectiveness of the proposed method.

  8. Spike-Based Bayesian-Hebbian Learning of Temporal Sequences.

    Directory of Open Access Journals (Sweden)

    Philip J Tully

    2016-05-01

    Full Text Available Many cognitive and motor functions are enabled by the temporal representation and processing of stimuli, but it remains an open issue how neocortical microcircuits can reliably encode and replay such sequences of information. To better understand this, a modular attractor memory network is proposed in which meta-stable sequential attractor transitions are learned through changes to synaptic weights and intrinsic excitabilities via the spike-based Bayesian Confidence Propagation Neural Network (BCPNN learning rule. We find that the formation of distributed memories, embodied by increased periods of firing in pools of excitatory neurons, together with asymmetrical associations between these distinct network states, can be acquired through plasticity. The model's feasibility is demonstrated using simulations of adaptive exponential integrate-and-fire model neurons (AdEx. We show that the learning and speed of sequence replay depends on a confluence of biophysically relevant parameters including stimulus duration, level of background noise, ratio of synaptic currents, and strengths of short-term depression and adaptation. Moreover, sequence elements are shown to flexibly participate multiple times in the sequence, suggesting that spiking attractor networks of this type can support an efficient combinatorial code. The model provides a principled approach towards understanding how multiple interacting plasticity mechanisms can coordinate hetero-associative learning in unison.

  9. Linear Temporal Logic (LTL) Based Monitoring of Smart Manufacturing Systems.

    Science.gov (United States)

    Heddy, Gerald; Huzaifa, Umer; Beling, Peter; Haimes, Yacov; Marvel, Jeremy; Weiss, Brian; LaViers, Amy

    2015-01-01

    The vision of Smart Manufacturing Systems (SMS) includes collaborative robots that can adapt to a range of scenarios. This vision requires a classification of multiple system behaviors, or sequences of movement, that can achieve the same high-level tasks. Likewise, this vision presents unique challenges regarding the management of environmental variables in concert with discrete, logic-based programming. Overcoming these challenges requires targeted performance and health monitoring of both the logical controller and the physical components of the robotic system. Prognostics and health management (PHM) defines a field of techniques and methods that enable condition-monitoring, diagnostics, and prognostics of physical elements, functional processes, overall systems, etc. PHM is warranted in this effort given that the controller is vulnerable to program changes, which propagate in unexpected ways, logical runtime exceptions, sensor failure, and even bit rot. The physical component's health is affected by the wear and tear experienced by machines constantly in motion. The controller's source of faults is inherently discrete, while the latter occurs in a manner that builds up continuously over time. Such a disconnect poses unique challenges for PHM. This paper presents a robotic monitoring system that captures and resolves this disconnect. This effort leverages supervisory robotic control and model checking with linear temporal logic (LTL), presenting them as a novel monitoring system for PHM. This methodology has been demonstrated in a MATLAB-based simulator for an industry inspired use-case in the context of PHM. Future work will use the methodology to develop adaptive, intelligent control strategies to evenly distribute wear on the joints of the robotic arms, maximizing the life of the system.

  10. Linear Temporal Logic (LTL) Based Monitoring of Smart Manufacturing Systems

    Science.gov (United States)

    Heddy, Gerald; Huzaifa, Umer; Beling, Peter; Haimes, Yacov; Marvel, Jeremy; Weiss, Brian; LaViers, Amy

    2017-01-01

    The vision of Smart Manufacturing Systems (SMS) includes collaborative robots that can adapt to a range of scenarios. This vision requires a classification of multiple system behaviors, or sequences of movement, that can achieve the same high-level tasks. Likewise, this vision presents unique challenges regarding the management of environmental variables in concert with discrete, logic-based programming. Overcoming these challenges requires targeted performance and health monitoring of both the logical controller and the physical components of the robotic system. Prognostics and health management (PHM) defines a field of techniques and methods that enable condition-monitoring, diagnostics, and prognostics of physical elements, functional processes, overall systems, etc. PHM is warranted in this effort given that the controller is vulnerable to program changes, which propagate in unexpected ways, logical runtime exceptions, sensor failure, and even bit rot. The physical component’s health is affected by the wear and tear experienced by machines constantly in motion. The controller’s source of faults is inherently discrete, while the latter occurs in a manner that builds up continuously over time. Such a disconnect poses unique challenges for PHM. This paper presents a robotic monitoring system that captures and resolves this disconnect. This effort leverages supervisory robotic control and model checking with linear temporal logic (LTL), presenting them as a novel monitoring system for PHM. This methodology has been demonstrated in a MATLAB-based simulator for an industry inspired use-case in the context of PHM. Future work will use the methodology to develop adaptive, intelligent control strategies to evenly distribute wear on the joints of the robotic arms, maximizing the life of the system. PMID:28730154

  11. Classification of temporal bone pneumatization based on sigmoid sinus using computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Han, S.-J. [Department of Otorhinolaryngology, National Health Insurance Corporation Ilsan Hospital, Seoul (Korea, Republic of); Song, M.H. [Department of Otorhinolaryngology, Yonsei University College of Medicine, Kang-nam Gu, Do-gok Dong, 146-92, Seoul, Republic of Korea 135-720 (Korea, Republic of); Kim, J. [Department of Radiology, Yonsei University College of Medicine, Seoul (Korea, Republic of); Lee, W.-S. [Department of Otorhinolaryngology, Yonsei University College of Medicine, Kang-nam Gu, Do-gok Dong, 146-92, Seoul, Republic of Korea 135-720 (Korea, Republic of); Lee, H.-K. [Department of Otorhinolaryngology, Yonsei University College of Medicine, Kang-nam Gu, Do-gok Dong, 146-92, Seoul, Republic of Korea 135-720 (Korea, Republic of)], E-mail: hoki@yuhs.ac

    2007-11-15

    Aim: To analyse several reference structures using axial computed tomography (CT) imaging of the temporal bone, which may reflect pneumatization of the entire temporal bone by statistical correlation to the actual volume of the temporal bone measured using three-dimensional reconstruction. Materials and methods: One hundred and sixteen temporal bones were studied, comprising 48 with normal findings and 68 sides showing chronic otitis media or temporal bone fracture. After measuring the volume of temporal bone air cells by the volume rendering technique using three-dimensional reconstruction images, classification of temporal bone pneumatization was performed using various reference structures on axial images to determine whether significant differences in the volume of temporal bone air cells could be found between the groups. Results: When the sigmoid sinus at the level of the malleoincudal complex was used in the classification, there were statistically significant differences between the groups that correlated with the entire volume of the temporal bone. Grouping based on the labyrinth and the ascending carotid artery showed insignificant differences in volume. Furthermore, there was no significant correlation between the cross-sectional area of the antrum and the entire volume of the temporal bone. Conclusion: The degree of pneumatization of temporal bone can be estimated easily by the evaluation of the air cells around the sigmoid sinus on axial CT images.

  12. PRECEDENCE AS A PSYCHOLINGUISTIC CATEGORY

    Directory of Open Access Journals (Sweden)

    Panarina Nadezhda Sergeevna

    2015-06-01

    Full Text Available The use of particular linguistic units by representatives of a linguacultural community as the most preferable verbal actions is not necessary to be a case of verbal operations with some culturally specific knowledge. The analysis of a psychosocial mechanism used for generation and verbalization of such a knowledge allows to define the nature of precedence as a characteristic of meaning that is being effected in a speech act. The development of precedent meaning indispensably assumes not only generation of the definition component, but also entry into a structure of a culturological component meaning. The culturological component reflects a relationship between a subject-concept component of the meaning and the other elements of a speech situation – the relationship, which is notional for a person. Importance of the relationship consists in fact that definition of its content represents to a person their social identity. Until a person understands the content of relationship, which is represented by the culturological component, the use of corresponding linguistic units to nominate new objects of reality is a supraliminal appeal to the precedent knowledge, a speech act. But for new acts of usage the main thing is definitely quality of relationship as a characteristic of the cultural group stability, and the linguistic unit usage derives a new function. When the culturological component of the meaning is not included into generalization, since it is irrelevant one, and the core of meaning is composed of new and more relevant for the usage features, you can no more realize the inner form of the precedent meaning. The outer form is still relevant, since it is kept in mind by the representatives of linguaculture as the one which is preferable for usage. In this case the linguistic unit is just a tool not related to verbal representation of socially significant attitude, and its usage is a speech operation, a way to perform different speech acts

  13. Temporal-based pericranial flaps for orbitofrontal Dural repair: A technical note and Review of the literature

    Directory of Open Access Journals (Sweden)

    Esther Dupépé

    2016-03-01

    Conclusions: A temporal-based pericranial flap represents an alternative vascularized pedicle flap to the classic frontal-based pericranial flap used in orbitofrontal dural repair. In certain clinical settings, the temporal-based flap may be preferable.

  14. Chord Recognition Based on Temporal Correlation Support Vector Machine

    Directory of Open Access Journals (Sweden)

    Zhongyang Rao

    2016-05-01

    Full Text Available In this paper, we propose a method called temporal correlation support vector machine (TCSVM for automatic major-minor chord recognition in audio music. We first use robust principal component analysis to separate the singing voice from the music to reduce the influence of the singing voice and consider the temporal correlations of the chord features. Using robust principal component analysis, we expect the low-rank component of the spectrogram matrix to contain the musical accompaniment and the sparse component to contain the vocal signals. Then, we extract a new logarithmic pitch class profile (LPCP feature called enhanced LPCP from the low-rank part. To exploit the temporal correlation among the LPCP features of chords, we propose an improved support vector machine algorithm called TCSVM. We perform this study using the MIREX’09 (Music Information Retrieval Evaluation eXchange Audio Chord Estimation dataset. Furthermore, we conduct comprehensive experiments using different pitch class profile feature vectors to examine the performance of TCSVM. The results of our method are comparable to the state-of-the-art methods that entered the MIREX in 2013 and 2014 for the MIREX’09 Audio Chord Estimation task dataset.

  15. A dynamic texture based approach to recognition of facial actions and their temporal models

    NARCIS (Netherlands)

    Koelstra, Sander; Pantic, Maja; Patras, Ioannis (Yannis)

    2010-01-01

    In this work, we propose a dynamic texture-based approach to the recognition of facial Action Units (AUs, atomic facial gestures) and their temporal models (i.e., sequences of temporal segments: neutral, onset, apex, and offset) in near-frontal-view face videos. Two approaches to modeling the

  16. Automata-Based Verification of Temporal Properties on Running Programs

    Science.gov (United States)

    Giannakopoulou, Dimitra; Havelund, Klaus; Lan, Sonie (Technical Monitor)

    2001-01-01

    This paper presents an approach to checking a running program against its Linear Temporal Logic (LTL) specifications. LTL is a widely used logic for expressing properties of programs viewed as sets of executions. Our approach consists of translating LTL formulae to finite-state automata, which are used as observers of the program behavior. The translation algorithm we propose modifies standard LTL to Buchi automata conversion techniques to generate automata that check finite program traces. The algorithm has been implemented in a tool, which has been integrated with the generic JPaX framework for runtime analysis of Java programs.

  17. Temporal imaging based on four-wave mixing in slow-light photonic crystal waveguide

    Science.gov (United States)

    Zhou, Mingyang; Liu, Hongjun; Wang, Zhaolu; Huang, Nan; Han, Jing

    2017-12-01

    We have proposed a temporal imaging system based on four-wave mixing (FWM) in the dispersion engineered slow-light photonic crystal waveguide (PCW). Dispersion relations of the modified PCW are calculated through the 3D plane wave expansion method. Time lens is demonstrated by solving the couple-mode equations describing the FWM process inside the PCW directly. Intensity and phase evolutions of the signal, pump and idler waves during the FWM process are calculated to investigate temporal imaging. Meanwhile, temporal magnifications with different magnification factors are realized by tuning the total dispersion of the input signals. Furthermore, influences of dispersion and free-carrier effects inside PCW on the temporal imaging performance are analyzed. The simulation results show the capability to realize temporal imaging system based on the FWM process in slow-light engineered PCW.

  18. Spatial-Temporal Analysis on Spring Festival Travel Rush in China Based on Multisource Big Data

    National Research Council Canada - National Science Library

    Li, Jiwei; Ye, Qingqing; Deng, Xuankai; Liu, Yaolin; Liu, Yanfang

    2016-01-01

    .... This study investigates the spatial-temporal characteristics of Spring Festival travel rush in 2015 through time series analysis and complex network analysis based on multisource big travel data...

  19. Contributions of cerebellar event-based temporal processing and preparatory function to speech perception.

    Science.gov (United States)

    Schwartze, Michael; Kotz, Sonja A

    2016-10-01

    The role of the cerebellum in the anatomical and functional architecture of the brain is a matter of ongoing debate. We propose that cerebellar temporal processing contributes to speech perception on a number of accounts: temporally precise cerebellar encoding and rapid transmission of an event-based representation of the temporal structure of the speech signal serves to prepare areas in the cerebral cortex for the subsequent perceptual integration of sensory information. As speech dynamically evolves in time this fundamental preparatory function may extend its scope to the predictive allocation of attention in time and supports the fine-tuning of temporally specific models of the environment. In this framework, an oscillatory account considering a range of frequencies may best serve the linking of the temporal and speech processing systems. Lastly, the concerted action of these processes may not only advance predictive adaptation to basic auditory dynamics but optimize the perceptual integration of speech. Copyright © 2015 Elsevier Inc. All rights reserved.

  20. Temporal association between land-based runoff events and California sea otter (Enhydra lutris nereis) protozoal mortalities.

    Science.gov (United States)

    Shapiro, Karen; Miller, Melissa; Mazet, Jonna

    2012-04-01

    Toxoplasma gondii and Sarcocystis neurona have caused significant morbidity and mortality in threatened Southern sea otters (Enhydra lutris nereis) along the central California coast. Because only terrestrial animals are known to serve as definitive hosts for T. gondii and S. neurona, infections in otters suggest a land to sea flow of these protozoan pathogens. To better characterize the role of overland runoff in delivery of terrestrially derived fecal pathogens to the near shore, we assessed the temporal association between indicators of runoff and the timing of sea otter deaths due to T. gondii and S. neurona. Sea otter stranding records 1998-2004, from Monterey and Estero bays were reviewed and cases identified for which T. gondii or S. neurona were determined to be a primary or contributing cause of death. Precipitation and stream flow data from both study sites were used as indicators of land-based runoff. Logistic regression was applied to determine if a temporal association could be detected between protozoal mortalities and runoff indicators that occur in the 2 mo preceding mortality events. A significant association was found between S. neurona otter deaths at Estero Bay and increased stream flow that occurred 30-60 days prior to mortality events. At this site, the cause of otter mortality following increased river flows was 12 times more likely to be S. neurona infection compared with nonprotozoal causes of death. There were no significant associations between the timing of T. gondii otter deaths and indicators of overland runoff. Our results indicate that the association between overland runoff and otter mortalities is affected by geography as well as parasite type, and highlight the complex mechanisms that influence transmission of terrestrially derived pathogens to marine wildlife. Policy and management practices that aim to mitigate discharges of contaminated overland runoff can aid conservation efforts by reducing pathogen pollution of coastal

  1. JUDICIAL PRECEDENT, A LAW SOURCE

    Directory of Open Access Journals (Sweden)

    Elena ANGHEL

    2017-05-01

    Full Text Available The role awarded to judge varies from one legal system to another. In the Anglo-Saxon legal systems, there is not a self-standing legislative body, so the judge is the one who creates the law; his mission consists in solving a specific case, given the existing judicial precedents; if he cannot find an appropriate rule of law, he has to develop one and to apply it. In the continental system, creation of law is the mission of the legislature, so the creative role of jurisprudence still raises controversy. Evolving under the influence of Roman law, the continental law systems differ from the Anglo-Saxon by: the continuous receiving of Corpus iuris civilis; the tendency to abstraction, leading to the creation of a rational law; the rule of law, with the consequence of blurring the role of jurisprudence. Underlining the creative force of jurisprudence, Vladimir Hanga wrote: "The law remains in its essence abstract, but the appreciation of the jurisprudence makes it alive, as the judge, understanding the law, taking into account the interests of parties and taking inspiration from equity, ensures the ultimate purpose of the law: suum cuique tribuere”.

  2. Tunable temporal gap based on simultaneous fast and slow light in electro-optic photonic crystals.

    Science.gov (United States)

    Li, Guangzhen; Chen, Yuping; Jiang, Haowei; Liu, Yi'an; Liu, Xiao; Chen, Xianfeng

    2015-07-13

    We demonstrated a tunable temporal gap based on simultaneous fast and slow light in electro-optic photonic crystals. The light experiences an anomalous dispersion near the transmission center and a normal dispersion away from the center, where it can be accelerated and slowed down, respectively. We also obtained the switch between fast and slow light by adjusting the external electric filed. The observed largest temporal gap is 541 ps, which is crucial in practical event operation inside the gap. The results offer a new solution for temporal cloak.

  3. Spatial-Temporal Epidemiology of Tuberculosis in Mainland China: An Analysis Based on Bayesian Theory

    OpenAIRE

    Kai Cao; Kun Yang; Chao Wang; Jin Guo; Lixin Tao; Qingrong Liu; Mahara Gehendra; Yingjie Zhang; Xiuhua Guo

    2016-01-01

    Objective: To explore the spatial-temporal interaction effect within a Bayesian framework and to probe the ecological influential factors for tuberculosis. Methods: Six different statistical models containing parameters of time, space, spatial-temporal interaction and their combination were constructed based on a Bayesian framework. The optimum model was selected according to the deviance information criterion (DIC) value. Coefficients of climate variables were then estimated using the best f...

  4. EIGENVECTOR-BASED CENTRALITY MEASURES FOR TEMPORAL NETWORKS*

    OpenAIRE

    Taylor, Dane; MYERS, SEAN A.; Clauset, Aaron; Porter, Mason A.; Mucha, Peter J.

    2017-01-01

    Numerous centrality measures have been developed to quantify the importances of nodes in time-independent networks, and many of them can be expressed as the leading eigenvector of some matrix. With the increasing availability of network data that changes in time, it is important to extend such eigenvector-based centrality measures to time-dependent networks. In this paper, we introduce a principled generalization of network centrality measures that is valid for any eigenvector-based centralit...

  5. Neural mechanisms of rhythm-based temporal prediction: Delta phase-locking reflects temporal predictability but not rhythmic entrainment.

    Directory of Open Access Journals (Sweden)

    Assaf Breska

    2017-02-01

    Full Text Available Predicting the timing of upcoming events enables efficient resource allocation and action preparation. Rhythmic streams, such as music, speech, and biological motion, constitute a pervasive source for temporal predictions. Widely accepted entrainment theories postulate that rhythm-based predictions are mediated by synchronizing low-frequency neural oscillations to the rhythm, as indicated by increased phase concentration (PC of low-frequency neural activity for rhythmic compared to random streams. However, we show here that PC enhancement in scalp recordings is not specific to rhythms but is observed to the same extent in less periodic streams if they enable memory-based prediction. This is inconsistent with the predictions of a computational entrainment model of stronger PC for rhythmic streams. Anticipatory change in alpha activity and facilitation of electroencephalogram (EEG manifestations of response selection are also comparable between rhythm- and memory-based predictions. However, rhythmic sequences uniquely result in obligatory depression of preparation-related premotor brain activity when an on-beat event is omitted, even when it is strategically beneficial to maintain preparation, leading to larger behavioral costs for violation of prediction. Thus, while our findings undermine the validity of PC as a sign of rhythmic entrainment, they constitute the first electrophysiological dissociation, to our knowledge, between mechanisms of rhythmic predictions and of memory-based predictions: the former obligatorily lead to resonance-like preparation patterns (that are in line with entrainment, while the latter allow flexible resource allocation in time regardless of periodicity in the input. Taken together, they delineate the neural mechanisms of three distinct modes of preparation: continuous vigilance, interval-timing-based prediction and rhythm-based prediction.

  6. Symmetry constraints on temporal order in measurement-based quantum computation

    Directory of Open Access Journals (Sweden)

    R. Raussendorf

    2012-10-01

    Full Text Available We discuss the interdependence of resource state, measurement setting and temporal order in measurement-based quantum computation. The possible temporal orders of measurement events are constrained by the principle that the randomness inherent in quantum measurement should not affect the outcome of the computation. We provide a classification for all temporal relations among measurement events compatible with a given initial stabilizer state and measurement setting, in terms of a matroid. Conversely, we show that classical processing relations necessary for turning the local measurement outcomes into computational output determine the resource state and measurement setting up to local equivalence. Further, we find a symmetry transformation related to local complementation that leaves the temporal relations invariant.

  7. Constraint-Based Abstract Semantics for Temporal Logic

    DEFF Research Database (Denmark)

    Banda, Gourinath; Gallagher, John Patrick

    2010-01-01

    Abstract interpretation provides a practical approach to verifying properties of infinite-state systems. We apply the framework of abstract interpretation to derive an abstract semantic function for the modal mu-calculus, which is the basis for abstract model checking. The abstract semantic funct...... abstract domains based on linear constraints. The implementation of the abstract semantic function makes use of an SMT solver. We describe an implemented system for proving properties of linear hybrid automata and give some experimental results....

  8. RSS Fingerprint Based Indoor Localization Using Sparse Representation with Spatio-Temporal Constraint.

    Science.gov (United States)

    Piao, Xinglin; Zhang, Yong; Li, Tingshu; Hu, Yongli; Liu, Hao; Zhang, Ke; Ge, Yun

    2016-11-03

    The Received Signal Strength (RSS) fingerprint-based indoor localization is an important research topic in wireless network communications. Most current RSS fingerprint-based indoor localization methods do not explore and utilize the spatial or temporal correlation existing in fingerprint data and measurement data, which is helpful for improving localization accuracy. In this paper, we propose an RSS fingerprint-based indoor localization method by integrating the spatio-temporal constraints into the sparse representation model. The proposed model utilizes the inherent spatial correlation of fingerprint data in the fingerprint matching and uses the temporal continuity of the RSS measurement data in the localization phase. Experiments on the simulated data and the localization tests in the real scenes show that the proposed method improves the localization accuracy and stability effectively compared with state-of-the-art indoor localization methods.

  9. Syntactic Idioms and Precedent Phenomena: Intersection Zones

    Directory of Open Access Journals (Sweden)

    Hanna Sytar

    2016-08-01

    Full Text Available Background: One examined mainly structural and semantic features of syntactic idioms so far. The pragmatic dimension of these original units that are on the verge of syntax and phraseology, has not been highlighted properly in the scientific literature, so it needs theoretical understanding. The combination of syntactic idiom and phraseological phenomenon refers to the communication techniques impacting on message recipient. Purpose: to analyze the intersection zones of syntactic idioms and precedent phenomena. Results: Analysis of the collected factual material allows to distinguish two areas of interpenetration of syntactic idioms and precedent units: 1 construction of expression according to the phraseologized model, within which the position of variable component is filled by the precedent name or precedent expression; 2 the model of sentence itself is precedent, and lexical content does not comply with generally known one that does not affect on understanding of model content by recipient. With a combination of syntactic idiom and precedent phenomena speakers provide drawing of recipients’ attention, carry out a hidden influence on them, express their own attitude to the realities, so that perform phatic, manipulative and expressive-evaluative functions. The modifications and transformations of precedent expressions and names appeared to be regular in such interpenetrations. Discussion: The obtained results reflect the general trend towards transform (transformation, modification, variation, etc. of precedent, as well as phraseological units, and can be used for the analysis of patterns of their formation and modifications. Further research phase implies tracing patterns of syntactic idioms combination with other means of expressive syntax.

  10. Compressed sensing based missing nodes prediction in temporal communication network

    Science.gov (United States)

    Cheng, Guangquan; Ma, Yang; Liu, Zhong; Xie, Fuli

    2018-02-01

    The reconstruction of complex network topology is of great theoretical and practical significance. Most research so far focuses on the prediction of missing links. There are many mature algorithms for link prediction which have achieved good results, but research on the prediction of missing nodes has just begun. In this paper, we propose an algorithm for missing node prediction in complex networks. We detect the position of missing nodes based on their neighbor nodes under the theory of compressed sensing, and extend the algorithm to the case of multiple missing nodes using spectral clustering. Experiments on real public network datasets and simulated datasets show that our algorithm can detect the locations of hidden nodes effectively with high precision.

  11. Spike-Based Bayesian-Hebbian Learning of Temporal Sequences

    DEFF Research Database (Denmark)

    Tully, Philip J; Lindén, Henrik; Hennig, Matthias H

    2016-01-01

    in which meta-stable sequential attractor transitions are learned through changes to synaptic weights and intrinsic excitabilities via the spike-based Bayesian Confidence Propagation Neural Network (BCPNN) learning rule. We find that the formation of distributed memories, embodied by increased periods...... of firing in pools of excitatory neurons, together with asymmetrical associations between these distinct network states, can be acquired through plasticity. The model's feasibility is demonstrated using simulations of adaptive exponential integrate-and-fire model neurons (AdEx). We show that the learning...... and speed of sequence replay depends on a confluence of biophysically relevant parameters including stimulus duration, level of background noise, ratio of synaptic currents, and strengths of short-term depression and adaptation. Moreover, sequence elements are shown to flexibly participate multiple times...

  12. Colour based fire detection method with temporal intensity variation filtration

    Science.gov (United States)

    Trambitckii, K.; Anding, K.; Musalimov, V.; Linß, G.

    2015-02-01

    Development of video, computing technologies and computer vision gives a possibility of automatic fire detection on video information. Under that project different algorithms was implemented to find more efficient way of fire detection. In that article colour based fire detection algorithm is described. But it is not enough to use only colour information to detect fire properly. The main reason of this is that in the shooting conditions may be a lot of things having colour similar to fire. A temporary intensity variation of pixels is used to separate them from the fire. These variations are averaged over the series of several frames. This algorithm shows robust work and was realised as a computer program by using of the OpenCV library.

  13. Galeal flap based on superficial temporal vessels for oral cavity and pharynx reconstruction: an anatomical study

    Directory of Open Access Journals (Sweden)

    Fabio Pinto

    2008-01-01

    Full Text Available PURPOSE: Despite the advances in microvascular free tissue transfer for intraoral reconstruction, this surgery is not recommended for all patients. In specific cases, the pedicled temporoparietal galeal flap may be an option for reconstructive procedures in the head and neck regions. The objective of this paper is to present the anatomical aspects of a galeal flap based on the superficial temporal vessels and to test its potential for reconstructing diverse sites of the oral cavity and pharynx. METHODS: We performed 40 dissections on 34 fresh adult cadavers. The flap vascular anatomy was studied by injecting latex into the superficial temporal vessels. A standardized square-shape flap measuring 10 x 10 cm², pedicled on the superficial temporal vessels, was raised. Oral cavity and oropharynx reconstruction simulations were performed after flap transposition into the mouth by passing it under the zygomatic arch. Hypopharyngeal reconstruction was tested by transposing the flap to the neck under the facial nerve. RESULTS: After latex injection, a rich vascular network over the temporoparietal galea was observed directly from the superficial temporal artery, and a well-vascularized flap based on this vessel was raised. In the reconstruction simulations, the flap was shown to be suitable for the coverage of hypothetical defects in most oral cavity and pharyngeal sites, mainly the retromolar trigone, tonsil area, and buccal mucosa. CONCLUSIONS: A galeal flap based on the superficial temporal vessels presents favorable anatomical characteristics for oral cavity and pharyngeal reconstruction.

  14. Research on target tracking algorithm based on spatio-temporal context

    Science.gov (United States)

    Li, Baiping; Xu, Sanmei; Kang, Hongjuan

    2017-07-01

    In this paper, a novel target tracking algorithm based on spatio-temporal context is proposed. During the tracking process, the camera shaking or occlusion may lead to the failure of tracking. The proposed algorithm can solve this problem effectively. The method use the spatio-temporal context algorithm as the main research object. We get the first frame's target region via mouse. Then the spatio-temporal context algorithm is used to get the tracking targets of the sequence of frames. During this process a similarity measure function based on perceptual hash algorithm is used to judge the tracking results. If tracking failed, reset the initial value of Mean Shift algorithm for the subsequent target tracking. Experiment results show that the proposed algorithm can achieve real-time and stable tracking when camera shaking or target occlusion.

  15. A hearing-aid signal-processing scheme based on the temporal aspects of compression

    Science.gov (United States)

    Carney, Laurel H.; Shi, Lufeng; Doherty, Karen A.

    2004-05-01

    Changes in gain associated with the basilar membrane compressive nonlinearity are accompanied by changes in the bandwidth of tuning. Filters with level-dependent bandwidth have level-dependent phase properties. These phase properties result in level-dependent timing of sustained phase-locked responses of auditory-nerve (AN) fibers at low frequencies and level-dependent latencies at high frequencies, where phase-locking rolls off. In the healthy ear, level-dependent temporal aspects of AN responses carry information about stimulus level and spectral properties. Loss of compression with hearing impairment thus results not only in a reduction of amplification, but also in distortion of the temporal response pattern of the AN. The temporal aspects of compression suggest that signal-processing schemes that attempt to correct sounds, or restore normal spatio-temporal response patterns, should include dynamic level-dependent phase shifts. A nonlinear signal-processing scheme will be presented which includes dynamic frequency- and level-dependent phase shifts, based on physiological models of the temporal response properties of AN fibers. Preliminary testing measured listeners preferences for sentences and intelligibility of vowel-consonant syllables with different degrees of nonlinear processing. Hearing-impaired listeners tended to prefer the dynamically corrected stimuli based on improved clarity. Correction also improved intelligibility for some phonemes. [Work supported by NIDCD R21-006057.

  16. Research of Cadastral Data Modelling and Database Updating Based on Spatio-temporal Process

    Directory of Open Access Journals (Sweden)

    ZHANG Feng

    2016-02-01

    Full Text Available The core of modern cadastre management is to renew the cadastre database and keep its currentness,topology consistency and integrity.This paper analyzed the changes and their linkage of various cadastral objects in the update process.Combined object-oriented modeling technique with spatio-temporal objects' evolution express,the paper proposed a cadastral data updating model based on the spatio-temporal process according to people's thought.Change rules based on the spatio-temporal topological relations of evolution cadastral spatio-temporal objects are drafted and further more cascade updating and history back trace of cadastral features,land use and buildings are realized.This model implemented in cadastral management system-ReGIS.Achieved cascade changes are triggered by the direct driving force or perceived external events.The system records spatio-temporal objects' evolution process to facilitate the reconstruction of history,change tracking,analysis and forecasting future changes.

  17. Ancient Chinese Precedents in China

    National Research Council Canada - National Science Library

    Geddis, Robert

    1999-01-01

    ... classics from ancient china. The assumption is that since China's political and military leaders state openly that their strategy is based on traditional Chinese strategic concepts, a study of ancient classics on strategy...

  18. Monitor-Based Statistical Model Checking for Weighted Metric Temporal Logic

    DEFF Research Database (Denmark)

    Bulychev, Petr; David, Alexandre; Larsen, Kim Guldstrand

    2012-01-01

    We present a novel approach and implementation for ana- lysing weighted timed automata (WTA) with respect to the weighted metric temporal logic (WMTL≤ ). Based on a stochastic semantics of WTAs, we apply statistical model checking (SMC) to estimate and test probabilities of satisfaction...

  19. An advection-based model to increase the temporal resolution of PIV time series

    NARCIS (Netherlands)

    Scarano, F.; Moore, P.

    2012-01-01

    A numerical implementation of the advection equation is proposed to increase the temporal resolution of PIV time series. The method is based on the principle that velocity fluctuations are transported passively, similar to Taylor’s hypothesis of frozen turbulence. In the present work, the advection

  20. Remote Sensing GIS Based Spatio-temporal Land Use/ Cover Study ...

    African Journals Online (AJOL)

    Remote Sensing GIS Based Spatio-temporal Land Use/ Cover Study of Western Ethiopian Highlands –A Case of Jima Arjo District. ... Extreme forest loss was recorded during the 1973 to 1986 years period were 112.6 sq. km has been lost. Wetlands were also showed reduction in extent. Of the original 84.52 sq.km wetland, ...

  1. Dose–Volume Relationships Associated With Temporal Lobe Radiation Necrosis After Skull Base Proton Beam Therapy

    Energy Technology Data Exchange (ETDEWEB)

    McDonald, Mark W., E-mail: markmcdonaldmd@gmail.com [Department of Radiation Oncology, Indiana University School of Medicine, Indianapolis, Indiana (United States); Indiana University Health Proton Therapy Center, Bloomington, Indiana (United States); Linton, Okechukwu R. [Department of Radiation Oncology, Indiana University School of Medicine, Indianapolis, Indiana (United States); Calley, Cynthia S.J. [Department of Biostatistics, Indiana University School of Medicine, Indianapolis, Indiana (United States)

    2015-02-01

    Purpose: We evaluated patient and treatment parameters correlated with development of temporal lobe radiation necrosis. Methods and Materials: This was a retrospective analysis of a cohort of 66 patients treated for skull base chordoma, chondrosarcoma, adenoid cystic carcinoma, or sinonasal malignancies between 2005 and 2012, who had at least 6 months of clinical and radiographic follow-up. The median radiation dose was 75.6 Gy (relative biological effectiveness [RBE]). Analyzed factors included gender, age, hypertension, diabetes, smoking status, use of chemotherapy, and the absolute dose:volume data for both the right and left temporal lobes, considered separately. A generalized estimating equation (GEE) regression analysis evaluated potential predictors of radiation necrosis, and the median effective concentration (EC50) model estimated dose–volume parameters associated with radiation necrosis. Results: Median follow-up time was 31 months (range 6-96 months) and was 34 months in patients who were alive. The Kaplan-Meier estimate of overall survival at 3 years was 84.9%. The 3-year estimate of any grade temporal lobe radiation necrosis was 12.4%, and for grade 2 or higher radiation necrosis was 5.7%. On multivariate GEE, only dose–volume relationships were associated with the risk of radiation necrosis. In the EC50 model, all dose levels from 10 to 70 Gy (RBE) were highly correlated with radiation necrosis, with a 15% 3-year risk of any-grade temporal lobe radiation necrosis when the absolute volume of a temporal lobe receiving 60 Gy (RBE) (aV60) exceeded 5.5 cm{sup 3}, or aV70 > 1.7 cm{sup 3}. Conclusions: Dose–volume parameters are highly correlated with the risk of developing temporal lobe radiation necrosis. In this study the risk of radiation necrosis increased sharply when the temporal lobe aV60 exceeded 5.5 cm{sup 3} or aV70 > 1.7 cm{sup 3}. Treatment planning goals should include constraints on the volume of temporal lobes receiving

  2. Estimation of Temporal Gait Parameters Using a Wearable Microphone-Sensor-Based System.

    Science.gov (United States)

    Wang, Cheng; Wang, Xiangdong; Long, Zhou; Yuan, Jing; Qian, Yueliang; Li, Jintao

    2016-12-17

    Most existing wearable gait analysis methods focus on the analysis of data obtained from inertial sensors. This paper proposes a novel, low-cost, wireless and wearable gait analysis system which uses microphone sensors to collect footstep sound signals during walking. This is the first time a microphone sensor is used as a wearable gait analysis device as far as we know. Based on this system, a gait analysis algorithm for estimating the temporal parameters of gait is presented. The algorithm fully uses the fusion of two feet footstep sound signals and includes three stages: footstep detection, heel-strike event and toe-on event detection, and calculation of gait temporal parameters. Experimental results show that with a total of 240 data sequences and 1732 steps collected using three different gait data collection strategies from 15 healthy subjects, the proposed system achieves an average 0.955 F1-measure for footstep detection, an average 94.52% accuracy rate for heel-strike detection and 94.25% accuracy rate for toe-on detection. Using these detection results, nine temporal related gait parameters are calculated and these parameters are consistent with their corresponding normal gait temporal parameters and labeled data calculation results. The results verify the effectiveness of our proposed system and algorithm for temporal gait parameter estimation.

  3. Estimation of Temporal Gait Parameters Using a Wearable Microphone-Sensor-Based System

    Directory of Open Access Journals (Sweden)

    Cheng Wang

    2016-12-01

    Full Text Available Most existing wearable gait analysis methods focus on the analysis of data obtained from inertial sensors. This paper proposes a novel, low-cost, wireless and wearable gait analysis system which uses microphone sensors to collect footstep sound signals during walking. This is the first time a microphone sensor is used as a wearable gait analysis device as far as we know. Based on this system, a gait analysis algorithm for estimating the temporal parameters of gait is presented. The algorithm fully uses the fusion of two feet footstep sound signals and includes three stages: footstep detection, heel-strike event and toe-on event detection, and calculation of gait temporal parameters. Experimental results show that with a total of 240 data sequences and 1732 steps collected using three different gait data collection strategies from 15 healthy subjects, the proposed system achieves an average 0.955 F1-measure for footstep detection, an average 94.52% accuracy rate for heel-strike detection and 94.25% accuracy rate for toe-on detection. Using these detection results, nine temporal related gait parameters are calculated and these parameters are consistent with their corresponding normal gait temporal parameters and labeled data calculation results. The results verify the effectiveness of our proposed system and algorithm for temporal gait parameter estimation.

  4. Autonomous signal separation microphone system based on the spatio-temporal gradient analysis

    Science.gov (United States)

    Teramoto, Kenbu; Tsuruta, Kosuke

    2005-04-01

    This paper presents a novel autonomous directivity microphone system based on the newly proposed spatio-temporal blind source separation. Recently, the methods of blind source separation and multi-deconvolution of source signals have been proposed in various fields, especially, acoustic applications including the cocktail-party problem. The blind source separation principally uses no a priori knowledge about parameters of convolution, filtering and mixing. In the simplest case of the blind source separation problems, observed mixed signals are linear combinations of unknown mutually statistically independent, zero-mean source signals. The spatio-temporal blind signal separation algorithm utilizes the linearity among the four signals: (1) temporal gradient, (2) x; (3) y; and (4) z-directional spatial gradients of the sound-pressure, all of which are governed by the equation of advection. The proposed method, therefore, has an ability to simplify the convolution blind source separation problems into the instantaneous blind source separation over the spatio-temporal gradient space. The acoustical experiments are performed with the particle velocity microphone (Microflown) successfully instead of sound pressure microphones. Because, x; y; and z-directional gradients of the sound pressure are equivalent the temporal derivatives of the corresponding directional particle velocities theoretically.

  5. Harnessing temporal modes for multi-photon quantum information processing based on integrated optics.

    Science.gov (United States)

    Harder, G; Ansari, V; Bartley, T J; Brecht, B; Silberhorn, C

    2017-08-06

    In the last few decades, there has been much progress on low loss waveguides, very efficient photon-number detectors and nonlinear processes. Engineered sum-frequency conversion is now at a stage where it allows operation on arbitrary temporal broadband modes, thus making the spectral degree of freedom accessible for information coding. Hereby the information is often encoded into the temporal modes of a single photon. Here, we analyse the prospect of using multi-photon states or squeezed states in different temporal modes based on integrated optics devices. We describe an analogy between mode-selective sum-frequency conversion and a network of spatial beam splitters. Furthermore, we analyse the limits on the achievable squeezing in waveguides with current technology and the loss limits in the conversion process.This article is part of the themed issue 'Quantum technology for the 21st century'. © 2017 The Author(s).

  6. Visibility-based Planners for Mobile Robots Capable to Handle Path Existence Queries in Temporal Logic

    Directory of Open Access Journals (Sweden)

    POMARLAN, M.

    2014-02-01

    Full Text Available Over the past few years, sampling based planner algorithms have been applied to planning queries formulated in path existence temporal logic, a formal system that allows more complex specifications on a solution path and is useful for task planning for mobile robots or synthesizing controllers for dynamical systems. In this paper, we extend the visibility heuristic to planners capable to handle finite path existence temporal logic queries. Our interest is justified by the visibility heuristic's ability to construct small roadmaps that are fast to search. We find that the visibility heuristic must be amended so that it can reliably handle temporal logic queries and we propose a suitable modification of the heuristic. We then present a method to extract a solution path from a roadmap, if such a solution exists. Finally, we show how the planner can be used to generate looping paths by augmenting it with a gap reduction step.

  7. A dynamic texture-based approach to recognition of facial actions and their temporal models.

    Science.gov (United States)

    Koelstra, Sander; Pantic, Maja; Patras, Ioannis

    2010-11-01

    In this work, we propose a dynamic texture-based approach to the recognition of facial Action Units (AUs, atomic facial gestures) and their temporal models (i.e., sequences of temporal segments: neutral, onset, apex, and offset) in near-frontal-view face videos. Two approaches to modeling the dynamics and the appearance in the face region of an input video are compared: an extended version of Motion History Images and a novel method based on Nonrigid Registration using Free-Form Deformations (FFDs). The extracted motion representation is used to derive motion orientation histogram descriptors in both the spatial and temporal domain. Per AU, a combination of discriminative, frame-based GentleBoost ensemble learners and dynamic, generative Hidden Markov Models detects the presence of the AU in question and its temporal segments in an input image sequence. When tested for recognition of all 27 lower and upper face AUs, occurring alone or in combination in 264 sequences from the MMI facial expression database, the proposed method achieved an average event recognition accuracy of 89.2 percent for the MHI method and 94.3 percent for the FFD method. The generalization performance of the FFD method has been tested using the Cohn-Kanade database. Finally, we also explored the performance on spontaneous expressions in the Sensitive Artificial Listener data set.

  8. Spatial and Temporal Dynamics and Value of Nature-Based Recreation, Estimated via Social Media.

    Science.gov (United States)

    Sonter, Laura J; Watson, Keri B; Wood, Spencer A; Ricketts, Taylor H

    2016-01-01

    Conserved lands provide multiple ecosystem services, including opportunities for nature-based recreation. Managing this service requires understanding the landscape attributes underpinning its provision, and how changes in land management affect its contribution to human wellbeing over time. However, evidence from both spatially explicit and temporally dynamic analyses is scarce, often due to data limitations. In this study, we investigated nature-based recreation within conserved lands in Vermont, USA. We used geotagged photographs uploaded to the photo-sharing website Flickr to quantify visits by in-state and out-of-state visitors, and we multiplied visits by mean trip expenditures to show that conserved lands contributed US $1.8 billion (US $0.18-20.2 at 95% confidence) to Vermont's tourism industry between 2007 and 2014. We found eight landscape attributes explained the pattern of visits to conserved lands; visits were higher in larger conserved lands, with less forest cover, greater trail density and more opportunities for snow sports. Some of these attributes differed from those found in other locations, but all aligned with our understanding of recreation in Vermont. We also found that using temporally static models to inform conservation decisions may have perverse outcomes for nature-based recreation. For example, static models suggest conserved land with less forest cover receive more visits, but temporally dynamic models suggest clearing forests decreases, rather than increases, visits to these sites. Our results illustrate the importance of understanding both the spatial and temporal dynamics of ecosystem services for conservation decision-making.

  9. Influential Factors of Mother-Infant Skin-to-Skin Contact Based on the Precede-Proceed Model from the Perspective of Midwives in Torbat Heydariyeh Hospitals

    Directory of Open Access Journals (Sweden)

    Mohadeseh Adeli

    2016-07-01

    Full Text Available Background & aim: Skin-to-skin contact immediately after birth plays a pivotal role in proper breastfeeding and mother-infant interaction. Despite numerous benefits of mother-infant skin-to-skin contact, this health behavior is not performed by many midwives. This study aimed to evaluate the influential factors for mother-infant skin-to-skin contact based on the Precede-Proceed model from the perspective of midwives in Torbat Heydariyeh hospitals. Methods:This cross-sectional study was conducted on 50 midwives working in hospitals of Torbat Heydariyeh, Iran in 2015. Demographic data of all participants were collected, and Mother-Newborn Skin-to-Skin Contact Questionnaire was also used based on the Precede-Proceed model. Data analysis was performed in SPSS V.16 using descriptive statistics, tables and graphs. Results: In this study, 88.1% of the midwives had positive attitudes towards skin-to-skin contact, and 90.5% had high perceived self-efficacy in performing the procedure. Major obstacles against establishing proper skin-to-skin contact were neonatal diseases and maternal fatigue (83.3% from the perspective of midwives. Moreover, 87.5% and 90.5% of the midwives emphasized the pivotal role of social support and motivation, respectively in implementing skin-to-skin contact. Also, more than 90% of the midwives considered training programs, service access and adequate facilities to be influential in the proper establishment of skin-to-skin contact. Conclusion: According to the results of this study, the majority of midwives believed that enabling and reinforcing factors had significant effects on the proper establishment of mother-infant skin-to-skin contact. Therefore, it is recommended thateducational interventions be planned for parents, their family members and health care personnel involved in processes of childbirth and infant care. Furthermore, organizational planning and executive procedures should be developed to study the

  10. Virtual temporal bone: an interactive 3-dimensional learning aid for cranial base surgery

    OpenAIRE

    Kockro, R A; Hwang, P Y

    2009-01-01

    OBJECTIVE: We have developed an interactive virtual model of the temporal bone for the training and teaching of cranial base surgery. METHODS: The virtual model was based on the tomographic data of the Visible Human Project. The male Visible Human's computed tomographic data were volumetrically reconstructed as virtual bone tissue, and the individual photographic slices provided the basis for segmentation of the middle and inner ear structures, cranial nerves, vessels, and brainstem. These st...

  11. Engaging concert hall acoustics is made up of temporal envelope preserving reflections.

    Science.gov (United States)

    Lokki, Tapio; Pätynen, Jukka; Tervo, Sakari; Siltanen, Samuel; Savioja, Lauri

    2011-06-01

    Strong, exciting, and engaging sound is perceived in the best concert halls. Here, it is shown that wideband early reflections that preserve the temporal envelope of sound contribute to the clear and open acoustics with strong bass. Such reflections are fused with the direct sound due to the precedence effect. In contrast, reflections that distort the temporal envelope render the sound weak and muddy because they partially break down the precedence. The presented findings are based on the earlier psychoacoustics research, and confirmed by a perceptual evaluation with six simulated concert halls that have same monaural room acoustical parameter values according to ISO3382-1. © 2011 Acoustical Society of America

  12. Temporal Data Set Reduction Based on D-Optimality for Quantitative FLIM-FRET Imaging.

    Directory of Open Access Journals (Sweden)

    Travis Omer

    Full Text Available Fluorescence lifetime imaging (FLIM when paired with Förster resonance energy transfer (FLIM-FRET enables the monitoring of nanoscale interactions in living biological samples. FLIM-FRET model-based estimation methods allow the quantitative retrieval of parameters such as the quenched (interacting and unquenched (non-interacting fractional populations of the donor fluorophore and/or the distance of the interactions. The quantitative accuracy of such model-based approaches is dependent on multiple factors such as signal-to-noise ratio and number of temporal points acquired when sampling the fluorescence decays. For high-throughput or in vivo applications of FLIM-FRET, it is desirable to acquire a limited number of temporal points for fast acquisition times. Yet, it is critical to acquire temporal data sets with sufficient information content to allow for accurate FLIM-FRET parameter estimation. Herein, an optimal experimental design approach based upon sensitivity analysis is presented in order to identify the time points that provide the best quantitative estimates of the parameters for a determined number of temporal sampling points. More specifically, the D-optimality criterion is employed to identify, within a sparse temporal data set, the set of time points leading to optimal estimations of the quenched fractional population of the donor fluorophore. Overall, a reduced set of 10 time points (compared to a typical complete set of 90 time points was identified to have minimal impact on parameter estimation accuracy (≈5%, with in silico and in vivo experiment validations. This reduction of the number of needed time points by almost an order of magnitude allows the use of FLIM-FRET for certain high-throughput applications which would be infeasible if the entire number of time sampling points were used.

  13. Temporal Data Set Reduction Based on D-Optimality for Quantitative FLIM-FRET Imaging.

    Science.gov (United States)

    Omer, Travis; Intes, Xavier; Hahn, Juergen

    2015-01-01

    Fluorescence lifetime imaging (FLIM) when paired with Förster resonance energy transfer (FLIM-FRET) enables the monitoring of nanoscale interactions in living biological samples. FLIM-FRET model-based estimation methods allow the quantitative retrieval of parameters such as the quenched (interacting) and unquenched (non-interacting) fractional populations of the donor fluorophore and/or the distance of the interactions. The quantitative accuracy of such model-based approaches is dependent on multiple factors such as signal-to-noise ratio and number of temporal points acquired when sampling the fluorescence decays. For high-throughput or in vivo applications of FLIM-FRET, it is desirable to acquire a limited number of temporal points for fast acquisition times. Yet, it is critical to acquire temporal data sets with sufficient information content to allow for accurate FLIM-FRET parameter estimation. Herein, an optimal experimental design approach based upon sensitivity analysis is presented in order to identify the time points that provide the best quantitative estimates of the parameters for a determined number of temporal sampling points. More specifically, the D-optimality criterion is employed to identify, within a sparse temporal data set, the set of time points leading to optimal estimations of the quenched fractional population of the donor fluorophore. Overall, a reduced set of 10 time points (compared to a typical complete set of 90 time points) was identified to have minimal impact on parameter estimation accuracy (≈5%), with in silico and in vivo experiment validations. This reduction of the number of needed time points by almost an order of magnitude allows the use of FLIM-FRET for certain high-throughput applications which would be infeasible if the entire number of time sampling points were used.

  14. Dengue Preceding Diabetic Ketoacidosis Dear Editor;

    Directory of Open Access Journals (Sweden)

    Viroj Wiwanitkit

    2013-12-01

    Full Text Available Diabetic ketoacidosis (DKA is an important hyperglycemic complication of diabetes mellitus. Infection is confirmed as an important underlying etiology of DKA. Here, the author presents an interesting case of dengue preceding DKA. The case is a 61-year-old female presenting to the physician with the complaint of high fever without relief by self-prescription of acetaminophen. She had an underlying disease, diabetes mellitus (DM. Her body temperature was 39.4 degrees Celsius and her complete blood count showed an important finding: thrombocytopenia (platelet count = 85.000. The serological test was done and the diagnosis of dengue hemorrhagic fever was finally confirmed. This case was treated by standard fluid replacement therapy (normal saline regimen. On day 3, the patient developed new symptoms, frequent urination (more than 3 times in an hour, abdominal pain, nausea, vomiting and rapid breathing. Complete blood count was done but platelet count was within normal limit at this time. However, the urinalysis showed many positive findings, sugar 4+ and ketone 3+. Her additional blood chemistry results showed a blood glucose level of 454 mg/dL and positive serum ketone. The patient was finally diagnosed to have DKA and endocrinologists were consulted for the management. Of interest, this is a simple case of DKA but the interesting issue is the underlying condition leading to DKA in this patient. Although there are many reports confirming that infection can induce DKA, this is the first reported case of dengue preceding DKA. Indeed, there is a previous report from Thailand on a female patient presented to the physician with concurrent DKA and dengue infection (1. However, DM had not previously been diagnosed in the present case. The dengue infection is common in the tropical world and DM is also the important emerging health problem in this area. Some reports note that DM can be an aggravating factor in the development of dengue shock (2,3. There is

  15. Substance abuse precedes Internet addiction.

    Science.gov (United States)

    Lee, Young Sik; Han, Doug Hyun; Kim, Sun Mi; Renshaw, Perry F

    2013-04-01

    The purpose of the current study was to evaluate possible overlapping substance abuse and internet addiction in a large, uniformly sampled population, ranging in age from 13 to 18 years. Participants (N=73,238) in the current study were drawn from the 6th Korea Youth Risk Behavior Web-based Survey (KYRBWS-V) for students from 400 middle schools and 400 high schools in 16 cities within South Korea. Of adolescent internet users, 85.2% were general users (GU), 11.9% were users with potential risk for internet addiction (PR), and 3.0% were users with high risk for internet addiction (HR). There was a difference in the number of students with alcohol drinking among the GU, PR, and HR groups (20.8% vs 23.1% vs 27.4%). There was a difference in the number of students who smoked among the GS, PR, and HR groups (11.7% vs 13.5% vs 20.4%). There was a difference in the number of students with drug use among the GU, PR, and HR groups (1.7% vs 2.0% vs 6.5%). After adjusting for sex, age, stress, depressed mood, and suicidal ideation, smoking may predict a high risk for internet addiction (OR=1.203, p=0.004). In addition, drug use may predict a high risk for internet addiction (OR=2.591, pinternet addiction have vulnerability for addictive behaviors, co-morbid substance abuse should be evaluated and, if found, treated in adolescents with internet addiction. Copyright © 2013 Elsevier Ltd. All rights reserved.

  16. Azimuth Ambiguities Removal in Littoral Zones Based on Multi-Temporal SAR Images

    Directory of Open Access Journals (Sweden)

    Xiangguang Leng

    2017-08-01

    Full Text Available Synthetic aperture radar (SAR is one of the most important techniques for ocean monitoring. Azimuth ambiguities are a real problem in SAR images today, which can cause performance degradation in SAR ocean applications. In particular, littoral zones can be strongly affected by land-based sources, whereas they are usually regions of interest (ROI. Given the presence of complexity and diversity in littoral zones, azimuth ambiguities removal is a tough problem. As SAR sensors can have a repeat cycle, multi-temporal SAR images provide new insight into this problem. A method for azimuth ambiguities removal in littoral zones based on multi-temporal SAR images is proposed in this paper. The proposed processing chain includes co-registration, local correlation, binarization, masking, and restoration steps. It is designed to remove azimuth ambiguities caused by fixed land-based sources. The idea underlying the proposed method is that sea surface is dynamic, whereas azimuth ambiguities caused by land-based sources are constant. Thus, the temporal consistence of azimuth ambiguities is higher than sea clutter. It opens up the possibilities to use multi-temporal SAR data to remove azimuth ambiguities. The design of the method and the experimental procedure are based on images from the Sentinel data hub of Europe Space Agency (ESA. Both Interferometric Wide Swath (IW and Stripmap (SM mode images are taken into account to validate the proposed method. This paper also presents two RGB composition methods for better azimuth ambiguities visualization. Experimental results show that the proposed method can remove azimuth ambiguities in littoral zones effectively.

  17. A FRAMEWORK FOR ONLINE SPATIO-TEMPORAL DATA VISUALIZATION BASED ON HTML5

    Directory of Open Access Journals (Sweden)

    B. Mao

    2012-07-01

    Full Text Available Web is entering a new phase – HTML5. New features of HTML5 should be studied for online spatio-temporal data visualization. In the proposed framework, spatio-temporal data is stored in the data server and is sent to user browsers with WebSocket. Public geo-data such as Internet digital map is integrated into the browsers. Then animation is implemented through the canvas object defined by the HTML5 specification. To simulate the spatio-temporal data source, we collected the daily location of 15 users with GPS tracker. The current positions of the users are collected every minute and are recorded in a file. Based on this file, we generate a real time spatio-temporal data source which sends out current user location every second.By enlarging the real time scales by 60 times, we can observe the movement clearly. The data transmitted with WebSocket is the coordinates of users' current positions, which will can be demonstrated in client browsers.

  18. Spatial-Temporal Epidemiology of Tuberculosis in Mainland China: An Analysis Based on Bayesian Theory.

    Science.gov (United States)

    Cao, Kai; Yang, Kun; Wang, Chao; Guo, Jin; Tao, Lixin; Liu, Qingrong; Gehendra, Mahara; Zhang, Yingjie; Guo, Xiuhua

    2016-05-05

    To explore the spatial-temporal interaction effect within a Bayesian framework and to probe the ecological influential factors for tuberculosis. Six different statistical models containing parameters of time, space, spatial-temporal interaction and their combination were constructed based on a Bayesian framework. The optimum model was selected according to the deviance information criterion (DIC) value. Coefficients of climate variables were then estimated using the best fitting model. The model containing spatial-temporal interaction parameter was the best fitting one, with the smallest DIC value (-4,508,660). Ecological analysis results showed the relative risks (RRs) of average temperature, rainfall, wind speed, humidity, and air pressure were 1.00324 (95% CI, 1.00150-1.00550), 1.01010 (95% CI, 1.01007-1.01013), 0.83518 (95% CI, 0.93732-0.96138), 0.97496 (95% CI, 0.97181-1.01386), and 1.01007 (95% CI, 1.01003-1.01011), respectively. The spatial-temporal interaction was statistically meaningful and the prevalence of tuberculosis was influenced by the time and space interaction effect. Average temperature, rainfall, wind speed, and air pressure influenced tuberculosis. Average humidity had no influence on tuberculosis.

  19. Spatial-Temporal Epidemiology of Tuberculosis in Mainland China: An Analysis Based on Bayesian Theory

    Directory of Open Access Journals (Sweden)

    Kai Cao

    2016-05-01

    Full Text Available Objective: To explore the spatial-temporal interaction effect within a Bayesian framework and to probe the ecological influential factors for tuberculosis. Methods: Six different statistical models containing parameters of time, space, spatial-temporal interaction and their combination were constructed based on a Bayesian framework. The optimum model was selected according to the deviance information criterion (DIC value. Coefficients of climate variables were then estimated using the best fitting model. Results: The model containing spatial-temporal interaction parameter was the best fitting one, with the smallest DIC value (−4,508,660. Ecological analysis results showed the relative risks (RRs of average temperature, rainfall, wind speed, humidity, and air pressure were 1.00324 (95% CI, 1.00150–1.00550, 1.01010 (95% CI, 1.01007–1.01013, 0.83518 (95% CI, 0.93732–0.96138, 0.97496 (95% CI, 0.97181–1.01386, and 1.01007 (95% CI, 1.01003–1.01011, respectively. Conclusions: The spatial-temporal interaction was statistically meaningful and the prevalence of tuberculosis was influenced by the time and space interaction effect. Average temperature, rainfall, wind speed, and air pressure influenced tuberculosis. Average humidity had no influence on tuberculosis.

  20. Whole-brain voxel-based morphometry of white matter in medial temporal lobe epilepsy

    Energy Technology Data Exchange (ETDEWEB)

    Yu Aihong [Department of Radiology, Xuanwu Hospital, Capital University of Medical Sciences, Beijing 100053 (China); Li Kuncheng [Department of Radiology, Xuanwu Hospital, Capital University of Medical Sciences, Beijing 100053 (China)], E-mail: Likuncheng@vip.sina.com; Li Lin; Shan Baoci [Institute of High Energy Physics, Chinese Academy of Sciences (China); Wang Yuping; Xue Sufang [Department of Neurology, Xuanwu Hospital, Capital University of Medical Sciences (China)

    2008-01-15

    Purpose: The purpose of this study was to analyze whole-brain white matter changes in medial temporal lobe epilepsy (MTLE). Materials and methods: We studied 23 patients with MTLE and 13 age- and sex-matched healthy control subjects using voxel-based morphometry (VBM) on T1-weighted 3D datasets. The seizure focus was right sided in 11 patients and left sided in 12. The data were collected on a 1.5 T MR system and analyzed by SPM 99 to generate white matter density maps. Results: Voxel-based morphometry revealed diffusively reduced white matter in MTLE prominently including bilateral frontal lobes, bilateral temporal lobes and corpus callosum. White matter reduction was also found in the bilateral cerebellar hemispheres in the left MTLE group. Conclusion: VBM is a simple and automated approach that is able to identify diffuse whole-brain white matter reduction in MTLE.

  1. Water body extraction and change detection based on multi-temporal SAR images

    Science.gov (United States)

    Zhang, Zhaohui; Lu, Hanqing; Zhao, Minghua; Zhao, Lei; Zhen, Huiling

    2009-10-01

    This paper proposed an unsupervised change detection method for water body extraction and change detection with multi-temporal SAR images. Firstly, two optimal thresholds are estimated according to the strategy of maximum mutual information, in which computation efficiency is largely improved based on integral image. Secondly, water body extraction is done simultaneously in both input images by optimal thresholds. Finally, by fusing of two segmented results, change detection can be achieved. Experimental results demonstrate the effectiveness of the proposed approach.

  2. Respiratory infections precede adult-onset asthma.

    Directory of Open Access Journals (Sweden)

    Aino Rantala

    Full Text Available BACKGROUND: Respiratory infections in early life are associated with an increased risk of developing asthma but there is little evidence on the role of infections for onset of asthma in adults. The objective of this study was to assess the relation of the occurrence of respiratory infections in the past 12 months to adult-onset asthma in a population-based incident case-control study of adults 21-63 years of age. METHODS/PRINCIPAL FINDINGS: We recruited all new clinically diagnosed cases of asthma (n = 521 during a 2.5-year study period and randomly selected controls (n = 932 in a geographically defined area in South Finland. Information on respiratory infections was collected by a self-administered questionnaire. The diagnosis of asthma was based on symptoms and reversible airflow obstruction in lung function measurements. The risk of asthma onset was strongly increased in subjects who had experienced in the preceding 12 months lower respiratory tract infections (including acute bronchitis and pneumonia with an adjusted odds ratio (OR 7.18 (95% confidence interval [CI] 5.16-9.99, or upper respiratory tract infections (including common cold, sinusitis, tonsillitis, and otitis media with an adjusted OR 2.26 (95% CI 1.72-2.97. Individuals with personal atopy and/or parental atopy were more susceptible to the effects of respiratory infections on asthma onset than non-atopic persons. CONCLUSIONS/SIGNIFICANCE: This study provides new evidence that recently experienced respiratory infections are a strong determinant for adult-onset asthma. Reducing such infections might prevent onset of asthma in adulthood, especially in individuals with atopy or hereditary propensity to it.

  3. Systems-based identification of temporal processing pathways during bone cell mechanotransduction.

    Directory of Open Access Journals (Sweden)

    Leah E Worton

    Full Text Available Bone has long been established to be a highly mechanosensitive tissue. When subjected to mechanical loading, bone exhibits profoundly different anabolic responses depending on the temporal pattern in which the stimulus is applied. This phenomenon has been termed temporal processing, and involves complex signal amplification mechanisms that are largely unidentified. In this study, our goal was to characterize transcriptomic perturbations arising from the insertion of intermittent rest periods (a temporal variation with profound effects on bone anabolism in osteoblastic cells subjected to fluid flow, and assess the utility of these perturbations to identify signaling pathways that are differentially activated by this temporal variation. At the level of the genome, we found that the common and differential alterations in gene expression arising from the two flow conditions were distributionally distinct, with the differential alterations characterized by many small changes in a large number of genes. Using bioinformatics analysis, we identified distinct up- and down-regulation transcriptomic signatures associated with the insertion of rest intervals, and found that the up-regulation signature was significantly associated with MAPK signaling. Confirming the involvement of the MAPK pathway, we found that the insertion of rest intervals significantly elevated flow-induced p-ERK1/2 levels by enabling a second spike in activity that was not observed in response to continuous flow. Collectively, these studies are the first to characterize distinct transcriptomic perturbations in bone cells subjected to continuous and intermittent stimulation, and directly demonstrate the utility of systems-based transcriptomic analysis to identify novel acute signaling pathways underlying temporal processing in bone cells.

  4. Metrical expectations from preceding prosody influence perception of lexical stress

    Science.gov (United States)

    Brown, Meredith; Salverda, Anne Pier; Dilley, Laura C.; Tanenhaus, Michael K.

    2015-01-01

    Two visual-world experiments tested the hypothesis that expectations based on preceding prosody influence the perception of suprasegmental cues to lexical stress. The results demonstrate that listeners’ consideration of competing alternatives with different stress patterns (e.g., ‘jury/gi’raffe) can be influenced by the fundamental frequency and syllable timing patterns across material preceding a target word. When preceding stressed syllables distal to the target word shared pitch and timing characteristics with the first syllable of the target word, pictures of alternatives with primary lexical stress on the first syllable (e.g., jury) initially attracted more looks than alternatives with unstressed initial syllables (e.g., giraffe). This effect was modulated when preceding unstressed syllables had pitch and timing characteristics similar to the initial syllable of the target word, with more looks to alternatives with unstressed initial syllables (e.g., giraffe) than to those with stressed initial syllables (e.g., jury). These findings suggest that expectations about the acoustic realization of upcoming speech include information about metrical organization and lexical stress, and that these expectations constrain the initial interpretation of suprasegmental stress cues. These distal prosody effects implicate on-line probabilistic inferences about the sources of acoustic-phonetic variation during spoken-word recognition. PMID:25621583

  5. Temporal moments revisited: Why there is no better way for physically based model reduction in time

    Science.gov (United States)

    Leube, P. C.; Nowak, W.; Schneider, G.

    2012-11-01

    Many hydro(geo)logical problems are highly complex in space and time, coupled with scale issues, variability, and uncertainty. Especially time-dependent models often consume enormous computational resources, but model reduction techniques can alleviate this problem. Temporal moments (TM) offer an approach to reduce the time demands of transient hydro(geo)logical simulations. TM reduce transient governing equations to steady state and directly simulate the temporal characteristics of the system, if the equations are linear and coefficients are time independent. This is achieved by an integral transform, projecting the dynamic system response onto monomials in time. In comparison to classical approaches of model reduction that involve orthogonal base functions, however, the monomials for TM are nonorthogonal, which might impair the quality and efficiency of model reduction. Thus, we raise the question of whether there are more suitable temporal base functions than the monomials that lead to TM. In this work, we will derive theoretically that there is only a limited class of temporal base functions that can reduce hydro(geo)logical models. By comparing those to TM we conclude that, in terms of gained efficiency versus maintained accuracy, TM are the best possible choice. While our theoretical results hold for all systems of linear partial or ordinary differential equations (PDEs, ODEs) with any order of space and time derivatives, we illustrate our study with an example of pumping tests in a confined aquifer. For that case, we demonstrate that two (four) TM are sufficient to represent more than 80% (90%) of the dynamic behavior, and that the information content strictly increases with increasing TM order.

  6. Scene-library-based video coding scheme exploiting long-term temporal correlation

    Science.gov (United States)

    Zuo, Xuguang; Yu, Lu; Yu, Hualong; Mao, Jue; Zhao, Yin

    2017-07-01

    In movies and TV shows, it is common that several scenes repeat alternately. These videos are characterized with the long-term temporal correlation, which can be exploited to improve video coding efficiency. However, in applications supporting random access (RA), a video is typically divided into a number of RA segments (RASs) by RA points (RAPs), and different RASs are coded independently. In such a way, the long-term temporal correlation among RASs with similar scenes cannot be used. We present a scene-library-based video coding scheme for the coding of videos with repeated scenes. First, a compact scene library is built by clustering similar scenes and extracting representative frames in encoding video. Then, the video is coded using a layered scene-library-based coding structure, in which the library frames serve as long-term reference frames. The scene library is not cleared by RAPs so that the long-term temporal correlation between RASs from similar scenes can be exploited. Furthermore, the RAP frames are coded as interframes by only referencing library frames so as to improve coding efficiency while maintaining RA property. Experimental results show that the coding scheme can achieve significant coding gain over state-of-the-art methods.

  7. Spatio-Temporal Regression Based Clustering of Precipitation Extremes in a Presence of Systematically Missing Covariates

    Science.gov (United States)

    Kaiser, Olga; Martius, Olivia; Horenko, Illia

    2017-04-01

    Regression based Generalized Pareto Distribution (GPD) models are often used to describe the dynamics of hydrological threshold excesses relying on the explicit availability of all of the relevant covariates. But, in real application the complete set of relevant covariates might be not available. In this context, it was shown that under weak assumptions the influence coming from systematically missing covariates can be reflected by a nonstationary and nonhomogenous dynamics. We present a data-driven, semiparametric and an adaptive approach for spatio-temporal regression based clustering of threshold excesses in a presence of systematically missing covariates. The nonstationary and nonhomogenous behavior of threshold excesses is describes by a set of local stationary GPD models, where the parameters are expressed as regression models, and a non-parametric spatio-temporal hidden switching process. Exploiting nonparametric Finite Element time-series analysis Methodology (FEM) with Bounded Variation of the model parameters (BV) for resolving the spatio-temporal switching process, the approach goes beyond strong a priori assumptions made is standard latent class models like Mixture Models and Hidden Markov Models. Additionally, the presented FEM-BV-GPD provides a pragmatic description of the corresponding spatial dependence structure by grouping together all locations that exhibit similar behavior of the switching process. The performance of the framework is demonstrated on daily accumulated precipitation series over 17 different locations in Switzerland from 1981 till 2013 - showing that the introduced approach allows for a better description of the historical data.

  8. Towards human behavior recognition based on spatio temporal features and support vector machines

    Science.gov (United States)

    Ghabri, Sawsen; Ouarda, Wael; Alimi, Adel M.

    2017-03-01

    Security and surveillance are vital issues in today's world. The recent acts of terrorism have highlighted the urgent need for efficient surveillance. There is indeed a need for an automated system for video surveillance which can detect identity and activity of person. In this article, we propose a new paradigm to recognize an aggressive human behavior such as boxing action. Our proposed system for human activity detection includes the use of a fusion between Spatio Temporal Interest Point (STIP) and Histogram of Oriented Gradient (HoG) features. The novel feature called Spatio Temporal Histogram Oriented Gradient (STHOG). To evaluate the robustness of our proposed paradigm with a local application of HoG technique on STIP points, we made experiments on KTH human action dataset based on Multi Class Support Vector Machines classification. The proposed scheme outperforms basic descriptors like HoG and STIP to achieve 82.26% us an accuracy value of classification rate.

  9. Full Waveform Modeling of Transient Electromagnetic Response Based on Temporal Interpolation and Convolution Method

    Science.gov (United States)

    Qi, Youzheng; Huang, Ling; Wu, Xin; Zhu, Wanhua; Fang, Guangyou; Yu, Gang

    2017-07-01

    Quantitative modeling of the transient electromagnetic (TEM) response requires consideration of the full transmitter waveform, i.e., not only the specific current waveform in a half cycle but also the bipolar repetition. In this paper, we present a novel temporal interpolation and convolution (TIC) method to facilitate the accurate TEM modeling. We first calculate the temporal basis response on a logarithmic scale using the fast digital-filter-based methods. Then, we introduce a function named hamlogsinc in the framework of discrete signal processing theory to reconstruct the basis function and to make the convolution with the positive half of the waveform. Finally, a superposition procedure is used to take account of the effect of previous bipolar waveforms. Comparisons with the established fast Fourier transform method demonstrate that our TIC method can get the same accuracy with a shorter computing time.

  10. Rapid and tunable method to temporally control gene editing based on conditional Cas9 stabilization.

    Science.gov (United States)

    Senturk, Serif; Shirole, Nitin H; Nowak, Dawid G; Corbo, Vincenzo; Pal, Debjani; Vaughan, Alexander; Tuveson, David A; Trotman, Lloyd C; Kinney, Justin B; Sordella, Raffaella

    2017-02-22

    The CRISPR/Cas9 system is a powerful tool for studying gene function. Here, we describe a method that allows temporal control of CRISPR/Cas9 activity based on conditional Cas9 destabilization. We demonstrate that fusing an FKBP12-derived destabilizing domain to Cas9 (DD-Cas9) enables conditional Cas9 expression and temporal control of gene editing in the presence of an FKBP12 synthetic ligand. This system can be easily adapted to co-express, from the same promoter, DD-Cas9 with any other gene of interest without co-modulation of the latter. In particular, when co-expressed with inducible Cre-ER T2 , our system enables parallel, independent manipulation of alleles targeted by Cas9 and traditional recombinase with single-cell specificity. We anticipate this platform will be used for the systematic characterization and identification of essential genes, as well as the investigation of the interactions between functional genes.

  11. Spatio-Temporal Pain Recognition in CNN-based Super-Resolved Facial Images

    DEFF Research Database (Denmark)

    Bellantonio, Marco; Haque, Mohammad Ahsanul; Rodriguez, Pau

    2017-01-01

    Automatic pain detection is a long expected solution to a prevalent medical problem of pain management. This is more relevant when the subject of pain is young children or patients with limited ability to communicate about their pain experience. Computer vision-based analysis of facial pain...... to pain in each of the facial video frames, temporal axis information regarding to pain expression pattern in a subject video sequence, and variation of face resolution. We employed a combination of convolutional neural network and recurrent neural network to setup a deep hybrid pain detection framework...... that is able to exploit both spatial and temporal pain information from facial video. In order to analyze the effect of different facial resolutions, we introduce a super-resolution algorithm to generate facial video frames with different resolution setups. We investigated the performance on the publicly...

  12. Temporal and spatial multiplexed infrared single-photon counter based on high-speed avalanche photodiode.

    Science.gov (United States)

    Chen, Xiuliang; Ding, Chengjie; Pan, Haifeng; Huang, Kun; Laurat, Julien; Wu, Guang; Wu, E

    2017-03-15

    We report on a high-speed temporal and spatial multiplexed single-photon counter with photon-number-resolving capability up to four photons. The infrared detector combines a fiber loop to split, delay and recombine optical pulses and a 200 MHz dual-channel single-photon detector based on InGaAs/InP avalanche photodiode. To fully characterize the photon-number-resolving capability, we perform quantum detector tomography and then reconstruct its positive-operator-valued measure and the associated Wigner functions. The result shows that, despite of the afterpulsing noise and limited system detection efficiency, this temporal and spatial multiplexed single-photon counter can already find applications for large repetition rate quantum information schemes.

  13. XML representation and management of temporal information for web-based cultural heritage applications

    Directory of Open Access Journals (Sweden)

    Fabio Grandi

    2006-01-01

    Full Text Available In this paper we survey the recent activities and achievements of our research group in the deployment of XMLrelated technologies in Cultural Heritage applications concerning the encoding of temporal semantics in Web documents. In particular we will review "The Valid Web", which is an XML/XSL infrastructure we defined and implemented for the definition and management of historical information within multimedia documents available on the Web, and its further extension to the effective encoding of advanced temporal features like indeterminacy, multiple granularities and calendars, enabling an efficient processing in a user-friendly Web-based environment. Potential uses of the developed infrastructures include a broad range of applications in the cultural heritage domain, where the historical perspective is relevant, with potentially positive impacts on E-Education and E-Science.

  14. A Similarity-Based Approach for Audiovisual Document Classification Using Temporal Relation Analysis

    Directory of Open Access Journals (Sweden)

    Ferrane Isabelle

    2011-01-01

    Full Text Available Abstract We propose a novel approach for video classification that bases on the analysis of the temporal relationships between the basic events in audiovisual documents. Starting from basic segmentation results, we define a new representation method that is called Temporal Relation Matrix (TRM. Each document is then described by a set of TRMs, the analysis of which makes events of a higher level stand out. This representation has been first designed to analyze any audiovisual document in order to find events that may well characterize its content and its structure. The aim of this work is to use this representation to compute a similarity measure between two documents. Approaches for audiovisual documents classification are presented and discussed. Experimentations are done on a set of 242 video documents and the results show the efficiency of our proposals.

  15. Temporal and spatial information extraction from videos based on the change in length of the shadow

    Science.gov (United States)

    Wang, Jiayun; Zu, Jian; Wang, Likang

    2017-03-01

    In this paper, considering the atmospheric refractive index, we present an approach to extract the recording date and geo-location from videos, based on the alteration of the shadow length. The paper carefully takes different information (photographed date, the length of the selected object) of the given video into consideration and forms a comprehensive approach to extract the temporal and spatial information of the given video. On the basis of this approach, we analyze the shadow length data of a chosen object from a real video and extract the temporal and spatial information of the video. Compared with the actual information, the error is less than 1%, which proves the validity of our approach.

  16. Discriminating bot accounts based solely on temporal features of microblog behavior

    Science.gov (United States)

    Pan, Junshan; Liu, Ying; Liu, Xiang; Hu, Hanping

    2016-05-01

    As the largest microblog service in China, Sina Weibo has attracted numerous automated applications (known as bots) due to its popularity and open architecture. We classify the active users from Sina Weibo into human, bot-based and hybrid groups based solely on the study of temporal features of their posting behavior. The anomalous burstiness parameter and time-interval entropy value are exploited to characterize automation. We also reveal different behavior patterns among the three types of users regarding their reposting ratio, daily rhythm and active days. Our findings may help Sina Weibo manage a better community and should be considered for dynamic models of microblog behaviors.

  17. Dual-PLL based on Temporal Redundancy for Radiation-Hardening

    OpenAIRE

    Kim, SinNyoung; Tsuchiya, Akira; Onodera, Hidetoshi

    2013-01-01

    This paper proposes a dual-PLL based on temporal redundancy for radiation-hardening. A common practice technique for radiation-hardening is the triple modular redundancy (TMR). However, it is inefficient to apply for PLLs because PLLs include huge size of capacitance and static current consumers, means analog circuits. Thus, we propose a dual-PLL and a detective circuit that detects a perturbed PLL by radiation-strike. Although our proposal is based on DMR, it allows both detecting and correc...

  18. Postfire regrowth trajectories of chamise chaparral based on multi-temporal Landsat imagery

    Science.gov (United States)

    Storey, Emanual A.

    Assessments of postfire recovery outcomes for the chamise chaparral shrublands of southern California provide a basis for land managers and ecologists to identify long-term changes in this sensitive ecosystem. Postfire vegetation recovery assessments based on fieldplot vegetation sampling and aerial image analysis have proven to be limited in coverage and inefficient for large areas of this landscape type. This study evaluates the potential of remotely sensed regrowth trajectories based on multi-temporal Landsat 4, 5, 7, and 8 satellite image observations for the postfire recovery assessment of chamise. Methods included: 1) an a priori determination of postfire shrub fractional cover changes based on multi-date high spatial resolution orthoimagery, 2) statistical testing to assess the sensitivity of regrowth trajectories based on several spectral vegetation indices and applied metrics to the recovery outcomes, and 3) an examination of regrowth trajectories which extend 19-29 years postfire relative to field-based measurements from other studies. Results provide a basis for interpretations about the sensitivities of the postfire regrowth trajectories derived from Landsat surface reflectance data to changes in the shrub matrix at various spatial and temporal scales. A primary finding was that several measures, including the Regeneration Index and another proposed here which is termed the Scaled Recovery Metric, enhanced the signals of postfire recovery derived from the multi-temporal trajectories and increased their comparability. Findings indicate that several of the spectral vegetation indices (NDVI, NDMI, NBR, and NBR2) were sensitive to long-term postfire changes in chamise, and that these same indices were statistically significant indicators of postfire recovery outcomes when certain metrics were applied. This study provides an overview of some advantages, limitations, and technical considerations of deriving postfire regrowth trajectories from Landsat imagery

  19. Sleep Disturbance Preceding Completed Suicide in Adolescents

    Science.gov (United States)

    Goldstein, Tina R.; Bridge, Jeffrey A.; Brent, David A.

    2008-01-01

    We examined sleep difficulties preceding death in a sample of adolescent suicide completers as compared with a matched sample of community control adolescents. Sleep disturbances were assessed in 140 adolescent suicide victims with a psychological autopsy protocol and in 131 controls with a similar semistructured psychiatric interview. Rates of…

  20. Updating Landsat-based forest cover maps with MODIS images using multiscale spectral-spatial-temporal superresolution mapping

    Science.gov (United States)

    Zhang, Yihang; Li, Xiaodong; Ling, Feng; Atkinson, Peter M.; Ge, Yong; Shi, Lingfei; Du, Yun

    2017-12-01

    With the high deforestation rates of global forest covers during the past decades, there is an ever-increasing need to monitor forest covers at both fine spatial and temporal resolutions. Moderate Resolution Imaging Spectroradiometer (MODIS) and Landsat series images have been used commonly for satellite-derived forest cover mapping. However, the spatial resolution of MODIS images and the temporal resolution of Landsat images are too coarse to observe forest cover at both fine spatial and temporal resolutions. In this paper, a novel multiscale spectral-spatial-temporal superresolution mapping (MSSTSRM) approach is proposed to update Landsat-based forest maps by integrating current MODIS images with the previous forest maps generated from Landsat image. Both the 240 m MODIS bands and 480 m MODIS bands were used as inputs of the spectral energy function of the MSSTSRM model. The principle of maximal spatial dependence was used as the spatial energy function to make the updated forest map spatially smooth. The temporal energy function was based on a multiscale spatial-temporal dependence model, and considers the land cover changes between the previous and current time. The novel MSSTSRM model was able to update Landsat-based forest maps more accurately, in terms of both visual and quantitative evaluation, than traditional pixel-based classification and the latest sub-pixel based super-resolution mapping methods The results demonstrate the great efficiency and potential of MSSTSRM for updating fine temporal resolution Landsat-based forest maps using MODIS images.

  1. Impulsivity as a precedent factor for problematic Internet use: How can we be sure?

    Science.gov (United States)

    Chen, Ssu-Kuang; Lo, Meng-Ting; Lin, Sunny S J

    2017-10-01

    Previous research has suggested that problematic Internet use (PIU) is associated with impulse control disorder. Although researchers have suggested that impulsivity is a risk factor for PIU, the literature lacks longitudinal evidence on the relationship between impulsivity and PIU. We aimed to use a cross-lagged analytic framework to identify temporal order effects and hypothesised that impulsivity was the precedent factor for PIU. In a panel sample of college students (N = 367), trait impulsivity and PIU were measured in the spring of freshman year and in their junior year. The measures included a self-developed PIU Scale and the revised Impulsiveness Scale based on Barratt's concept. We found that "non-planning impulsivity" was not associated with PIU. The "motor impulsivity" subfactor was thus adopted in the cross-lagged model. The results suggest that motor impulsivity and PIU were stable across time. Motor impulsivity at Time 1 positively predicted PIU at Time 2, but PIU at Time 1 did not predict motor impulsivity at Time 2. A further investigation using gender as a moderator found a gender difference in the temporal relationship. Because motor impulsivity is a risk factor for PIU, potential prevention strategies based on this result are suggested. © 2015 International Union of Psychological Science.

  2. Extended precedence preservative crossover for job shop scheduling problems

    Science.gov (United States)

    Ong, Chung Sin; Moin, Noor Hasnah; Omar, Mohd

    2013-04-01

    Job shop scheduling problems (JSSP) is one of difficult combinatorial scheduling problems. A wide range of genetic algorithms based on the two parents crossover have been applied to solve the problem but multi parents (more than two parents) crossover in solving the JSSP is still lacking. This paper proposes the extended precedence preservative crossover (EPPX) which uses multi parents for recombination in the genetic algorithms. EPPX is a variation of the precedence preservative crossover (PPX) which is one of the crossovers that perform well to find the solutions for the JSSP. EPPX is based on a vector to determine the gene selected in recombination for the next generation. Legalization of children (offspring) can be eliminated due to the JSSP representation encoded by using permutation with repetition that guarantees the feasibility of chromosomes. The simulations are performed on a set of benchmarks from the literatures and the results are compared to ensure the sustainability of multi parents recombination in solving the JSSP.

  3. BMRC: A Bitmap-Based Maximum Range Counting Approach for Temporal Data in Sensor Monitoring Networks

    Directory of Open Access Journals (Sweden)

    Bin Cao

    2017-09-01

    Full Text Available Due to the rapid development of the Internet of Things (IoT, many feasible deployments of sensor monitoring networks have been made to capture the events in physical world, such as human diseases, weather disasters and traffic accidents, which generate large-scale temporal data. Generally, the certain time interval that results in the highest incidence of a severe event has significance for society. For example, there exists an interval that covers the maximum number of people who have the same unusual symptoms, and knowing this interval can help doctors to locate the reason behind this phenomenon. As far as we know, there is no approach available for solving this problem efficiently. In this paper, we propose the Bitmap-based Maximum Range Counting (BMRC approach for temporal data generated in sensor monitoring networks. Since sensor nodes can update their temporal data at high frequency, we present a scalable strategy to support the real-time insert and delete operations. The experimental results show that the BMRC outperforms the baseline algorithm in terms of efficiency.

  4. An Ontology-Based Temporal Scheduling and Complexity Reduction Model for Timetabling Knowledge Management

    Directory of Open Access Journals (Sweden)

    Patience Usoro Usip

    2017-08-01

    Full Text Available Technological tools such as Semantic Web and ontologies have contributed immensely to the reduction of most managerial complexities on daily basis. However, most resolved complexities are solely dependent on the emerging issues which are not general enough to accommodate some specific domain challenges. Temporal scheduling complexities occur in several domains including timetabling, but inter-departmental courses allocation on a general institutional timetable has not been considered. This poses serious managerial concerns and threats to the academic performance of any institution. This paper is aimed at formalizing an ontology model for analyzing temporal scheduling complexities in an existing schedule and giving optimal possible time scheduling resolutions showing their reduction rates for efficient and intelligent knowledge management. Protégé was used in modeling the domain ontology described in the resulted ontograf. The semantics of the formal ontology model is described based on Allen’s interval temporal relations. The use of ontologies make way for easy and intelligent reasoning with knowledge and exposes the need for such knowledge management tool to manage the influx of the numerous data.

  5. Nonnegative Matrix Factorization-Based Spatial-Temporal Clustering for Multiple Sensor Data Streams

    Directory of Open Access Journals (Sweden)

    Di-Hua Sun

    2014-01-01

    Full Text Available Cyber physical systems have grown exponentially and have been attracting a lot of attention over the last few years. To retrieve and mine the useful information from massive amounts of sensor data streams with spatial, temporal, and other multidimensional information has become an active research area. Moreover, recent research has shown that clusters of streams change with a comprehensive spatial-temporal viewpoint in real applications. In this paper, we propose a spatial-temporal clustering algorithm (STClu based on nonnegative matrix trifactorization by utilizing time-series observational data streams and geospatial relationship for clustering multiple sensor data streams. Instead of directly clustering multiple data streams periodically, STClu incorporates the spatial relationship between two sensors in proximity and integrates the historical information into consideration. Furthermore, we develop an iterative updating optimization algorithm STClu. The effectiveness and efficiency of the algorithm STClu are both demonstrated in experiments on real and synthetic data sets. The results show that the proposed STClu algorithm outperforms existing methods for clustering sensor data streams.

  6. Explicit Precedence Constraints in Safety-Critical Java

    DEFF Research Database (Denmark)

    Puffitsch, Wolfgang; Noulard, Eric; Pagetti, Claire

    2013-01-01

    Safety-critical Java (SCJ) aims at making the amenities of Java available for the development of safety-critical applications. The multi-rate synchronous language Prelude facilitates the specification of the communication and timing requirements of complex real-time systems. This paper combines...... to provide explicit support for precedence constraints. We present the considerations behind the design of this extension and discuss our experiences with a first prototype implementation based on the SCJ implementation of the Java Optimized Processor....

  7. Spatial and temporal trends in alcohol consumption in Belgian cities: A wastewater-based approach.

    Science.gov (United States)

    Boogaerts, Tim; Covaci, Adrian; Kinyua, Juliet; Neels, Hugo; van Nuijs, Alexander L N

    2016-03-01

    In recent years, scientific evidence has emerged that wastewater-based epidemiology can deliver complementary information concerning the use of different substances of abuse. In this study, the potential of wastewater-based epidemiology in monitoring spatial and temporal trends in alcohol consumption in different populations in Belgium has been examined. Concentrations of ethyl sulphate, a minor Phase-II metabolite of ethanol, in 163 influent wastewater samples from eight wastewater treatment plants in Belgium in the period 2013-2015 were measured with liquid chromatography coupled to tandem mass spectrometry and used to estimate alcohol consumption. The highest levels of alcohol consumption were detected in the metropoles Antwerp and Brussels compared to smaller villages. Annual variations were detected, with a higher alcohol consumption measured in 2013 compared with 2014. The weekly pattern showed a clear week and weekend difference in alcohol use, with intermediate levels on Monday and Friday. The results were extrapolated and a use of 5.6L pure alcohol per year per inhabitant aged 15+ has been estimated in Belgium. The comparison with available information on drinking habits of the Belgian population further demonstrated the usefulness of the wastewater-based epidemiology approach. This is the largest wastewater-based epidemiology study monitoring alcohol consumption to date, demonstrating that objective and quick information on spatio-temporal trends in alcohol consumption on a local and (inter)national scale can be obtained. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  8. Model-Based Speech Signal Coding Using Optimized Temporal Decomposition for Storage and Broadcasting Applications

    Science.gov (United States)

    Athaudage, Chandranath R. N.; Bradley, Alan B.; Lech, Margaret

    2003-12-01

    A dynamic programming-based optimization strategy for a temporal decomposition (TD) model of speech and its application to low-rate speech coding in storage and broadcasting is presented. In previous work with the spectral stability-based event localizing (SBEL) TD algorithm, the event localization was performed based on a spectral stability criterion. Although this approach gave reasonably good results, there was no assurance on the optimality of the event locations. In the present work, we have optimized the event localizing task using a dynamic programming-based optimization strategy. Simulation results show that an improved TD model accuracy can be achieved. A methodology of incorporating the optimized TD algorithm within the standard MELP speech coder for the efficient compression of speech spectral information is also presented. The performance evaluation results revealed that the proposed speech coding scheme achieves 50%-60% compression of speech spectral information with negligible degradation in the decoded speech quality.

  9. Temporal subtraction system on torso FDG-PET scans based on statistical image analysis

    Science.gov (United States)

    Shimizu, Yusuke; Hara, Takeshi; Fukuoka, Daisuke; Zhou, Xiangrong; Muramatsu, Chisako; Ito, Satoshi; Hakozaki, Kenta; Kumita, Shin-ichiro; Ishihara, Kei-ichi; Katafuchi, Tetsuro; Fujita, Hiroshi

    2013-02-01

    Diagnostic imaging on FDG-PET scans was often used to evaluate chemotherapy results of cancer patients. Radiologists compare the changes of lesions' activities between previous and current examinations for the evaluation. The purpose of this study was to develop a new computer-aided detection (CAD) system with temporal subtraction technique for FDGPET scans and to show the fundamental usefulness based on an observer performance study. Z-score mapping based on statistical image analysis was newly applied to the temporal subtraction technique. The subtraction images can be obtained based on the anatomical standardization results because all of the patients' scans were deformed into standard body shape. An observer study was performed without and with computer outputs to evaluate the usefulness of the scheme by ROC (receiver operating characteristics) analysis. Readers responded as confidence levels on a continuous scale from absolutely no change to definitely change between two examinations. The recognition performance of the computer outputs for the 43 pairs was 96% sensitivity with 31.1 false-positive marks per scan. The average of area-under-the-ROC-curve (AUC) from 4 readers in the observer performance study was increased from 0.85 without computer outputs to 0.90 with computer outputs (p=0.0389, DBM-MRMC). The average of interpretation time was slightly decreased from 42.11 to 40.04 seconds per case (p=0.625, Wilcoxon test). We concluded that the CAD system for torso FDG-PET scans with temporal subtraction technique might improve the diagnostic accuracy of radiologist in cancer therapy evaluation.

  10. A polarized digital shearing speckle pattern interferometry system based on temporal wavelet transformation.

    Science.gov (United States)

    Feng, Ziang; Gao, Zhan; Zhang, Xiaoqiong; Wang, Shengjia; Yang, Dong; Yuan, Hao; Qin, Jie

    2015-09-01

    Digital shearing speckle pattern interferometry (DSSPI) has been recognized as a practical tool in testing strain. The DSSPI system which is based on temporal analysis is attractive because of its ability to measure strain dynamically. In this paper, such a DSSPI system with Wollaston prism has been built. The principles and system arrangement are described and the preliminary experimental result of the displacement-derivative test of an aluminum plate is shown with the wavelet transformation method and the Fourier transformation method. The simulations have been conducted with the finite element method. The comparison of the results shows that quantitative measurement of displacement-derivative has been realized.

  11. A Small UAV Based Multi-Temporal Image Registration for Dynamic Agricultural Terrace Monitoring

    Directory of Open Access Journals (Sweden)

    Ziquan Wei

    2017-08-01

    Full Text Available Terraces are the major land-use type of agriculture and support the main agricultural production in southeast and southwest China. However, due to smallholder farming, complex terrains, natural disasters and illegal land occupations, a light-weight and low cost dynamic monitoring of agricultural terraces has become a serious concern for smallholder production systems in the above area. In this work, we propose a small unmanned aerial vehicle (UAV based multi-temporal image registration method that plays an important role in transforming multi-temporal images into one coordinate system and determines the effectiveness of the subsequent change detection for dynamic agricultural terrace monitoring. The proposed method consists of four steps: (i guided image filtering based agricultural terrace image preprocessing, (ii texture and geometric structure features extraction and combination, (iii multi-feature guided point set registration, and (iv feature points based image registration. We evaluated the performance of the proposed method by 20 pairs of aerial images captured from Longji and Yunhe terraces, China using a small UAV (the DJI Phantom 4 Pro, and also compared against four state-of-the-art methods where our method shows the best alignments in most cases.

  12. a Web-Based Interactive Platform for Co-Clustering Spatio-Temporal Data

    Science.gov (United States)

    Wu, X.; Poorthuis, A.; Zurita-Milla, R.; Kraak, M.-J.

    2017-09-01

    Since current studies on clustering analysis mainly focus on exploring spatial or temporal patterns separately, a co-clustering algorithm is utilized in this study to enable the concurrent analysis of spatio-temporal patterns. To allow users to adopt and adapt the algorithm for their own analysis, it is integrated within the server side of an interactive web-based platform. The client side of the platform, running within any modern browser, is a graphical user interface (GUI) with multiple linked visualizations that facilitates the understanding, exploration and interpretation of the raw dataset and co-clustering results. Users can also upload their own datasets and adjust clustering parameters within the platform. To illustrate the use of this platform, an annual temperature dataset from 28 weather stations over 20 years in the Netherlands is used. After the dataset is loaded, it is visualized in a set of linked visualizations: a geographical map, a timeline and a heatmap. This aids the user in understanding the nature of their dataset and the appropriate selection of co-clustering parameters. Once the dataset is processed by the co-clustering algorithm, the results are visualized in the small multiples, a heatmap and a timeline to provide various views for better understanding and also further interpretation. Since the visualization and analysis are integrated in a seamless platform, the user can explore different sets of co-clustering parameters and instantly view the results in order to do iterative, exploratory data analysis. As such, this interactive web-based platform allows users to analyze spatio-temporal data using the co-clustering method and also helps the understanding of the results using multiple linked visualizations.

  13. A statistics-based temporal filter algorithm to map spatiotemporally continuous shortwave albedo from MODIS data

    Directory of Open Access Journals (Sweden)

    N. F. Liu

    2013-06-01

    Full Text Available Land-surface albedo plays a critical role in the earth's radiant energy budget studies. Satellite remote sensing provides an effective approach to acquire regional and global albedo observations. Owing to cloud coverage, seasonal snow and sensor malfunctions, spatiotemporally continuous albedo datasets are often inaccessible. The Global LAnd Surface Satellite (GLASS project aims at providing a suite of key land surface parameter datasets with high temporal resolution and high accuracy for a global change study. The GLASS preliminary albedo datasets are global daily land-surface albedo generated by an angular bin algorithm (Qu et al., 2013. Like other products, the GLASS preliminary albedo datasets are affected by large areas of missing data; beside, sharp fluctuations exist in the time series of the GLASS preliminary albedo due to data noise and algorithm uncertainties. Based on the Bayesian theory, a statistics-based temporal filter (STF algorithm is proposed in this paper to fill data gaps, smooth albedo time series, and generate the GLASS final albedo product. The results of the STF algorithm are smooth and gapless albedo time series, with uncertainty estimations. The performance of the STF method was tested on one tile (H25V05 and three ground stations. Results show that the STF method has greatly improved the integrity and smoothness of the GLASS final albedo product. Seasonal trends in albedo are well depicted by the GLASS final albedo product. Compared with MODerate resolution Imaging Spectroradiometer (MODIS product, the GLASS final albedo product has a higher temporal resolution and more competence in capturing the surface albedo variations. It is recommended that the quality flag should be always checked before using the GLASS final albedo product.

  14. Identification of influential nodes based on temporal-aware modeling of multi-hop neighbor interactions for influence spread maximization

    Science.gov (United States)

    Ullah, Farman; Lee, Sungchang

    2017-11-01

    This paper presents the identification of highly influential nodes based on temporal-aware modeling of multi-hop neighbor interactions to maximize the spread of information in online social networks (OSNs). The objective is to choose a set of influential nodes that have higher temporal multi-hop interactions and more topological connections in large-scale OSNs to maximize information dissemination and minimize spreading time. An influence diffusion process that is solely based on topology is not able to capture the influence spreading efficiently. A temporal multi-hops social interaction based centrality is proposed to choose nodes of higher spreading ability considering the nodes' neighbors and neighbors-of-neighbors temporal modeled interactions and topological connections. The temporal-aware interactions are modeled to find users who are more active recently. First, we model the influence between users considering the temporal interactions of the user and its neighbors. A subset of nodes with a higher influence value and more topological connections with direct neighbors is selected. Secondly, we select the Top- K higher influential spreader nodes from the subset of nodes considering the node neighbors and neighbors-of-neighbors temporal modeled social interactions and topological connections. Finally, the proposed algorithm is evaluated using the epidemic spreading models. The experimental results show that the algorithm is able to extract highly influential nodes that maximize the spread of information and minimize contagion time.

  15. Project Temporalities

    DEFF Research Database (Denmark)

    Tryggestad, Kjell; Justesen, Lise; Mouritsen, Jan

    2013-01-01

    Purpose – The purpose of this paper is to explore how animals can become stakeholders in interaction with project management technologies and what happens with project temporalities when new and surprising stakeholders become part of a project and a recognized matter of concern to be taken...... into account. Design/methodology/approach – The paper is based on a qualitative case study of a project in the building industry. The authors use actor-network theory (ANT) to analyze the emergence of animal stakeholders, stakes and temporalities. Findings – The study shows how project temporalities can...... multiply in interaction with project management technologies and how conventional linear conceptions of project time may be contested with the emergence of new non-human stakeholders and temporalities. Research limitations/implications – The study draws on ANT to show how animals can become stakeholders...

  16. Understanding structure of urban traffic network based on spatial-temporal correlation analysis

    Science.gov (United States)

    Yang, Yanfang; Jia, Limin; Qin, Yong; Han, Shixiu; Dong, Honghui

    2017-08-01

    Understanding the structural characteristics of urban traffic network comprehensively can provide references for improving road utilization rate and alleviating traffic congestion. This paper focuses on the spatial-temporal correlations between different pairs of traffic series and proposes a complex network-based method of constructing the urban traffic network. In the network, the nodes represent road segments, and an edge between a pair of nodes is added depending on the result of significance test for the corresponding spatial-temporal correlation. Further, a modified PageRank algorithm, named the geographical weight-based PageRank algorithm (GWPA), is proposed to analyze the spatial distribution of important segments in the road network. Finally, experiments are conducted by using three kinds of traffic series collected from the urban road network in Beijing. Experimental results show that the urban traffic networks constructed by three traffic variables all indicate both small-world and scale-free characteristics. Compared with the results of PageRank algorithm, GWPA is proved to be valid in evaluating the importance of segments and identifying the important segments with small degree.

  17. Agent Based Modeling: Fine-Scale Spatio-Temporal Analysis of Pertussis

    Science.gov (United States)

    Mills, D. A.

    2017-10-01

    In epidemiology, spatial and temporal variables are used to compute vaccination efficacy and effectiveness. The chosen resolution and scale of a spatial or spatio-temporal analysis will affect the results. When calculating vaccination efficacy, for example, a simple environment that offers various ideal outcomes is often modeled using coarse scale data aggregated on an annual basis. In contrast to the inadequacy of this aggregated method, this research uses agent based modeling of fine-scale neighborhood data centered around the interactions of infants in daycare and their families to demonstrate an accurate reflection of vaccination capabilities. Despite being able to prevent major symptoms, recent studies suggest that acellular Pertussis does not prevent the colonization and transmission of Bordetella Pertussis bacteria. After vaccination, a treated individual becomes a potential asymptomatic carrier of the Pertussis bacteria, rather than an immune individual. Agent based modeling enables the measurable depiction of asymptomatic carriers that are otherwise unaccounted for when calculating vaccination efficacy and effectiveness. Using empirical data from a Florida Pertussis outbreak case study, the results of this model demonstrate that asymptomatic carriers bias the calculated vaccination efficacy and reveal a need for reconsidering current methods that are widely used for calculating vaccination efficacy and effectiveness.

  18. Measuring Attention and Visual Processing Speed by Model-based Analysis of Temporal-order Judgments.

    Science.gov (United States)

    Tünnermann, Jan; Krüger, Alexander; Scharlau, Ingrid

    2017-01-23

    This protocol describes how to conduct temporal-order experiments to measure visual processing speed and the attentional resource distribution. The proposed method is based on a new and synergistic combination of three components: the temporal-order judgments (TOJ) paradigm, Bundesen's Theory of Visual Attention (TVA), and a hierarchical Bayesian estimation framework. The method provides readily interpretable parameters, which are supported by the theoretical and neurophysiological underpinnings of TVA. Using TOJs, TVA-based estimates can be obtained for a broad range of stimuli, whereas traditional paradigms used with TVA are mainly limited to letters and digits. Finally, the meaningful parameters of the proposed model allow for the establishment of a hierarchical Bayesian model. Such a statistical model allows assessing results in one coherent analysis both on the subject and the group level. To demonstrate the feasibility and versatility of this new approach, three experiments are reported with attention manipulations in synthetic pop-out displays, natural images, and a cued letter-report paradigm.

  19. Gaussian process based independent analysis for temporal source separation in fMRI

    DEFF Research Database (Denmark)

    Hald, Ditte Høvenhoff; Henao, Ricardo; Winther, Ole

    2017-01-01

    temporal nature. fMRI source signals, biological stimuli and non-stimuli-related artifacts are all smooth over a time-scale compatible with the sampling time (TR). We therefore propose Gaussian process ICA (GPICA), which facilitates temporal dependency by the use of Gaussian process source priors. On two f......MRI data sets with different sampling frequency, we show that the GPICA-inferred temporal components and associated spatial maps allow for a more definite interpretation than standard temporal ICA methods. The temporal structures of the sources are controlled by the covariance of the Gaussian process......, specified by a kernel function with an interpretable and controllable temporal length scale parameter. We propose a hierarchical model specification, considering both instantaneous and convolutive mixing, and we infer source spatial maps, temporal patterns and temporal length scale parameters by Markov...

  20. Voxel-based morphometry (VBM) based assessment of gray matter loss in medial temporal lobe epilepsy; comparison with FDG PET

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Hye Jin; Lee, Ho Young; Lee, Jae Sung; Kang, Eun Joo; Lee, Sang Gun; Chang, Kee Hyun; Lee, Dong Soo [College of Medicine, Seoul National Univ., Seoul (Korea, Republic of)

    2004-02-01

    The aims of this study were to find brain regions in which gray matter volume was reduced and to show the capability of voxel-based morphometry (VBM) analysis for lateralizing epileptogenic zones in medial temporal lobe epilepsy (mTLE). The findings were compared with fluorodeoxyglucose positron emission tomography (FDG PET). MR T1-weighted images of 12 left mTLE and 11 right mTLE patients were compared with those of 37 normal controls. Images were transformed to standard MNI space and averaged in order to create study-specific brain template. Each image was normalized to this local template and brain tissues were segmented. Modulation VBM analysis was performed in order to observe gray matter volume change. Gray matter was smoothed with a Gaussian kernel. After these preprocessing, statistical analysis was performed using statistical parametric mapping software (SPM99). FDG PET images were compared with those of 22 normal controls using SPM. Gray matter volume was significantly reduced in the left amygdala and hippocampus in left mTLE. In addition, volume of cerebellum, anterior cingulate, and fusiform gyrus in both sides and left insula was reduced. In right mTLE, volume was reduced significantly in right hippocampus. In contrast, FDG uptake was decreased in broad areas of left or right temporal lobes in left TLE and right TLE, respectively. Gray matter loss was found in the ipsilateral hippocampus by modulation VBM analysis in medial temporal lobe epilepsy. This VBM analysis might be useful in lateralizing the epileptogenic zones in medial temporal lobe epilepsy, while SPM analysis of FDG PET disclosed hypometabolic epileptogenic zones.

  1. A Stock Trading Recommender System Based on Temporal Association Rule Mining

    Directory of Open Access Journals (Sweden)

    Binoy B. Nair

    2015-04-01

    Full Text Available Recommender systems capable of discovering patterns in stock price movements and generating stock recommendations based on the patterns thus discovered can significantly supplement the decision-making process of a stock trader. Such recommender systems are of great significance to a layperson who wishes to profit by stock trading even while not possessing the skill or expertise of a seasoned trader. A genetic algorithm optimized Symbolic Aggregate approXimation (SAX–Apriori based stock trading recommender system, which can mine temporal association rules from the stock price data set to generate stock trading recommendations, is presented in this article. The proposed system is validated on 12 different data sets. The results indicate that the proposed system significantly outperforms the passive buy-and-hold strategy, offering scope for a layperson to successfully invest in capital markets.

  2. Satellite-based forest monitoring: spatial and temporal forecast of growing index and short-wave infrared band

    Directory of Open Access Journals (Sweden)

    Caroline Bayr

    2016-04-01

    Full Text Available For detecting anomalies or interventions in the field of forest monitoring we propose an approach based on the spatial and temporal forecast of satellite time series data. For each pixel of the satellite image three different types of forecasts are provided, namely spatial, temporal and combined spatio-temporal forecast. Spatial forecast means that a clustering algorithm is used to group the time series data based on the features normalised difference vegetation index (NDVI and the short-wave infrared band (SWIR. For estimation of the typical temporal trajectory of the NDVI and SWIR during the vegetation period of each spatial cluster, we apply several methods of functional data analysis including functional principal component analysis, and a novel form of random regression forests with online learning (streaming capability. The temporal forecast is carried out by means of functional time series analysis and an autoregressive integrated moving average model. The combination of the temporal forecasts, which is based on the past of the considered pixel, and spatial forecasts, which is based on highly correlated pixels within one cluster and their past, is performed by functional data analysis, and a variant of random regression forests adapted to online learning capabilities. For evaluation of the methods, the approaches are applied to a study area in Germany for monitoring forest damages caused by wind-storm, and to a study area in Spain for monitoring forest fires.

  3. Satellite-based forest monitoring: spatial and temporal forecast of growing index and short-wave infrared band.

    Science.gov (United States)

    Bayr, Caroline; Gallaun, Heinz; Kleb, Ulrike; Kornberger, Birgit; Steinegger, Martin; Winter, Martin

    2016-04-18

    For detecting anomalies or interventions in the field of forest monitoring we propose an approach based on the spatial and temporal forecast of satellite time series data. For each pixel of the satellite image three different types of forecasts are provided, namely spatial, temporal and combined spatio-temporal forecast. Spatial forecast means that a clustering algorithm is used to group the time series data based on the features normalised difference vegetation index (NDVI) and the short-wave infrared band (SWIR). For estimation of the typical temporal trajectory of the NDVI and SWIR during the vegetation period of each spatial cluster, we apply several methods of functional data analysis including functional principal component analysis, and a novel form of random regression forests with online learning (streaming) capability. The temporal forecast is carried out by means of functional time series analysis and an autoregressive integrated moving average model. The combination of the temporal forecasts, which is based on the past of the considered pixel, and spatial forecasts, which is based on highly correlated pixels within one cluster and their past, is performed by functional data analysis, and a variant of random regression forests adapted to online learning capabilities. For evaluation of the methods, the approaches are applied to a study area in Germany for monitoring forest damages caused by wind-storm, and to a study area in Spain for monitoring forest fires.

  4. Spatio-temporal control strategy of drug delivery systems based nano structures.

    Science.gov (United States)

    Rahoui, Nahla; Jiang, Bo; Taloub, Nadia; Huang, Yu Dong

    2017-06-10

    The drug instability, toxicity and the barrier to the target area necessitate a suitable drug delivery system with an external or internal control of the release. Spatio-temporal control using a surface functionalized nano-carrier seems to be the best alternative for guided drug delivery and release. This manuscript provides a broad spectrum about the drug carrier interface modification to cover the need for temporal drug delivery control under neglect side effects. On the other hand, recent advances related to the drug vehicle are highlighted, besides physical (Electric field, magnetic field, light) or mechanical (Ultrasound, mechanical strain), chemical (pH, redox gradient, enzyme) stimuli mediated DDS. Precisely, the paper focus on the NIR light as an effective external stimulus for remotely-triggered DDS. NIR responsive drug delivery systems are considered as novel drug modality that ensures an eco-friendly spatiotemporal control and an administrated meditation. This study also investigated the NIIR spectroscopy (NIRS) combined with partial least square (PLS) for quantitative analysis of a polyvinyl alcohol based prodrug (PVA-DOX) in order to reveal the high potential of NIRS for drug release monitoring and the extraction of concise calibration models. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. MAP-MRF-Based Super-Resolution Reconstruction Approach for Coded Aperture Compressive Temporal Imaging

    Directory of Open Access Journals (Sweden)

    Tinghua Zhang

    2018-02-01

    Full Text Available Coded Aperture Compressive Temporal Imaging (CACTI can afford low-cost temporal super-resolution (SR, but limits are imposed by noise and compression ratio on reconstruction quality. To utilize inter-frame redundant information from multiple observations and sparsity in multi-transform domains, a robust reconstruction approach based on maximum a posteriori probability and Markov random field (MAP-MRF model for CACTI is proposed. The proposed approach adopts a weighted 3D neighbor system (WNS and the coordinate descent method to perform joint estimation of model parameters, to achieve the robust super-resolution reconstruction. The proposed multi-reconstruction algorithm considers both total variation (TV and ℓ 2 , 1 norm in wavelet domain to address the minimization problem for compressive sensing, and solves it using an accelerated generalized alternating projection algorithm. The weighting coefficient for different regularizations and frames is resolved by the motion characteristics of pixels. The proposed approach can provide high visual quality in the foreground and background of a scene simultaneously and enhance the fidelity of the reconstruction results. Simulation results have verified the efficacy of our new optimization framework and the proposed reconstruction approach.

  6. A METHOD TO ESTIMATE TEMPORAL INTERACTION IN A CONDITIONAL RANDOM FIELD BASED APPROACH FOR CROP RECOGNITION

    Directory of Open Access Journals (Sweden)

    P. M. A. Diaz

    2016-06-01

    Full Text Available This paper presents a method to estimate the temporal interaction in a Conditional Random Field (CRF based approach for crop recognition from multitemporal remote sensing image sequences. This approach models the phenology of different crop types as a CRF. Interaction potentials are assumed to depend only on the class labels of an image site at two consecutive epochs. In the proposed method, the estimation of temporal interaction parameters is considered as an optimization problem, whose goal is to find the transition matrix that maximizes the CRF performance, upon a set of labelled data. The objective functions underlying the optimization procedure can be formulated in terms of different accuracy metrics, such as overall and average class accuracy per crop or phenological stages. To validate the proposed approach, experiments were carried out upon a dataset consisting of 12 co-registered LANDSAT images of a region in southeast of Brazil. Pattern Search was used as the optimization algorithm. The experimental results demonstrated that the proposed method was able to substantially outperform estimates related to joint or conditional class transition probabilities, which rely on training samples.

  7. Temporal profile monitor based on electro-optic spatial decoding for low-energy bunches

    Directory of Open Access Journals (Sweden)

    Wei Wang

    2017-11-01

    Full Text Available The measurement of electron bunch temporal profile is one of the key diagnostics in accelerators, especially for ultrashort bunches. The electro-optic (EO technique enables the precise longitudinal characterization of bunch electric field in a single-shot and nondestructive way, which can simultaneously obtain and analyze the time jitter between the electron bunch and the synchronized laser. An EO monitor based on spatial decoding for temporal profile measurement and timing jitter recoding has recently been demonstrated and analyzed in depth for low-energy bunches at the Tsinghua Thomson scattering X-ray source. A detailed description of the experimental setup and measurement results are presented in this paper. An EO signal as short as 82 fs (rms is observed with 100  μm gallium phosphide for a 40 MeV electron bunch, and the corresponding length is 106 fs (rms with 300  μm zinc telluride. Owing to the field-opening angle, we propose a method to eliminate the influence of energy factor for bunches with low energy, resulting in a bunch length of ∼60  fs (rms. The monitor is also successfully applied to measure time jitter with approximately 10 fs accuracy. The experiment environment is proved to be the main source of the slow drift, which is removed using feedback control. Consequently, the rms time jitter decreases from 430 fs to 320 fs.

  8. AREA-BASED SNOW DAMAGE CLASSIFICATION OF FOREST CANOPIES USING BI- TEMPORAL LIDAR DATA

    Directory of Open Access Journals (Sweden)

    M. Vastaranta

    2012-09-01

    Full Text Available Multitemporal LiDAR data provide means for mapping structural changes in forest canopies. We demonstrate the use of area-based estimation method for snow damage assessment. Change features of bi-temporal LiDAR point height distributions were used as predictors in combination with in situ training data. In the winter 2009–2010, snow damages occurred in Hyytiälä (62°N, 24°E, southern Finland. Snow load resulted in broken, bent and fallen trees changing the canopy structure. The damages were documented at the tree level at permanent field plots and dense LiDAR data from 2007 and 2010 were used in the analyses. A 5 × 5-m grid was established in one pine%ndash;spruce stand and change metrics from the LiDAR point height distribution were extracted for the cells. Cells were classified as damaged (n = 43 or undamaged (n = 42 based on the field data. Stepwise logistic regression detected the damaged cells with an overall accuracy of 78.6% (Kappa = 0.57. The best predictors were differences in h-distribution percentage points 5, 35, 40, 50 and 70 of first-or-single return data. The tentative results from the single stand suggest that dense bi-temporal LiDAR data and an area-based approach could be feasible in mapping canopy changes. The accuracy of the point h-distribution is dependent on the pulse density per grid cell. Depending on the time span between LiDAR acquisitions, the natural changes of the h- distributions due to tree growth need to be accounted for as well as differences in the scanning geometry, which can substantially affect the LiDAR h-metrics.

  9. Oral lichen planus preceding concomitant lichen planopilaris.

    Science.gov (United States)

    Stoopler, Eric T; Alfaris, Sausan; Alomar, Dalal; Alawi, Faizan

    2016-09-01

    Lichen planus (LP) is an immune-mediated mucocutaneous disorder with a wide array of clinical presentations. Oral lichen planus (OLP) is characterized clinically by striae, desquamation, and/or ulceration. Lichen planopilaris (LPP), a variant of LP, affects the scalp, resulting in perifollicular erythema and scarring of cutaneous surfaces accompanied by hair loss. The association between OLP and LPP has been reported previously with scant information on concomitant or sequential disease presentation. We describe a patient with concomitant OLP and LPP, and to the best of our knowledge, this is the first report on OLP preceding the onset of LPP. Copyright © 2016 Elsevier Inc. All rights reserved.

  10. Acute disseminated encephalomyelitis preceding measles exanthema.

    Science.gov (United States)

    Nardone, Raffaele; Golaszewski, Stefan; Trinka, Eugen; Tezzon, Frediano; Zuccoli, Giulio

    2011-12-01

    We report a case of acute disseminated encephalomyelitis preceding measles virus infection. Brain magnetic resonance imaging revealed signal intensity abnormalities in the basal ganglia and cortex consistent with acute disseminated encephalomyelitis. Fever and the first Koplik spots appeared 8 and 10 days later, respectively. This case supports the hypothesis that the immune-mediated demyelinating process may occur before the symptomatic phase of a viral infection. Therefore, children without history of infectious disorders should also have acute disseminated encephalomyelitis included in the differential considerations.

  11. Brain Musics: History, Precedents, and Commentary on Whalley, Mavros and Furniss

    National Research Council Canada - National Science Library

    Miguel Ortiz; Mick Grierson; Atau Tanaka

    2015-01-01

    .... With our commentary, we contextualize the work within the field of Music Neuroscience. Specifically, we point at precedents in EEG-based musical practice as well as ongoing research in the field...

  12. Weather dependent estimation of continent-wide wind power generation based on spatio-temporal clustering

    Science.gov (United States)

    Schyska, Bruno U.; Couto, António; von Bremen, Lueder; Estanqueiro, Ana; Heinemann, Detlev

    2017-05-01

    Europe is facing the challenge of increasing shares of energy from variable renewable sources. Furthermore, it is heading towards a fully integrated electricity market, i.e. a Europe-wide electricity system. The stable operation of this large-scale renewable power system requires detailed information on the amount of electricity being transmitted now and in the future. To estimate the actual amount of electricity, upscaling algorithms are applied. Those algorithms - until now - however, only exist for smaller regions (e.g. transmission zones and single wind farms). The aim of this study is to introduce a new approach to estimate Europe-wide wind power generation based on spatio-temporal clustering. We furthermore show that training the upscaling model for different prevailing weather situations allows to further reduce the number of reference sites without losing accuracy.

  13. Identification of the heart wall and chamber based on temporal change of ultrasonic scatterer distribution

    Science.gov (United States)

    Takahashi, Kohei; Taki, Hirofumi; Kanai, Hiroshi

    2017-07-01

    In most current methods for evaluating the cardiac function by ultrasound, the heart wall area is identified manually by an examiner. To eliminate examiner dependence and to improve usability, an automatic heart wall identification method is desirable. Identification based on only echogenicity often fails because of low echogenicity of some areas of the heart wall. In the present study, to determine more essential features, we focused on the relative temporal change of ultrasonic scatterer distribution and proposed three features for identification of the heart wall and the chamber: cross-correlation of RF signals, that of envelopes, and spatial dispersion of movement vectors in small regions. In an in vivo experiment, using echogenicity and the three features, we identified the heart wall and the chamber in the left ventricular long-axis view, resulting in criteria of separability J of 1.69, 1.40, and 3.02 using these features compared with the result of 0.979 using echogenicity.

  14. Improvement of axial excitation confinement in temporal focusing-based multiphoton microscopy via spatially modulated illumination

    Science.gov (United States)

    Chang, Chia-Yuan; Chen, Shean-Jen

    2017-02-01

    Conventional temporal focusing-based multiphoton excitation microscopy (TFMPEM) can offer widefield optical sectioning with an axial excitation confinement (AEC) of a few microns. Herein, a developed TFMPEM with a digital micromirror device (DMD), acting as the blazed grating for light spatial dispersion and simultaneous patterned illumination, has been extended to implement spatially modulated illumination at structured frequency and orientation. By implementing the spatially modulated illumination, the beam coverage at the back-focal aperture of the objective lens can be increased. As a result, the AEC can be condensed from 3.0 μm to 1.5 μm in full width at half maximum for a 2-fold enhancement. Furthermore, by using HiLo microscopy with two structured illuminations at the same spatial frequency but different orientation, biotissue images according to the structured illumination with condensed AEC is obviously superior in contrast and scattering suppression.

  15. Preceding movement effects on sequential aiming.

    Science.gov (United States)

    Cheng, Darian T; De Grosbois, John; Smirl, Jonathan; Heath, Matthew; Binsted, Gordon

    2011-11-01

    In this study, two experiments were devised to examine the control strategy used by individuals when performing sequential aiming movements. Of particular interest was the aiming behavior displayed when task difficulty was changed midway through a sequence of movements. In Experiment 1, target size was manipulated, as the targets were made either larger or smaller, between the 8th and 12th movement of the sequence. In Experiment 2, the amplitude between the two targets was similarly changed while the target size remained constant. Results revealed that in Experiment 1, individuals took two movements following the perturbation to target size, to re-tune their movement times in order to correspond with the new task difficulty. Conversely for Experiment 2, movement time changed immediately and in correspondence with the new target amplitude. These findings demonstrate that participants can use information from the preceding movement to prepare and guide subsequent movements--but only when target size is changed. When response amplitude changes mid-sequence, it seems individuals rely more on immediate, target-derived information. Therefore, counter to some current accounts of visual movement control, it appears that memory representations of the preceding movement can guide subsequent movements; however, this information appears selectively accessed in a context-dependent fashion.

  16. National-scale cropland mapping based on spectral-temporal features and outdated land cover information.

    Science.gov (United States)

    Waldner, François; Hansen, Matthew C; Potapov, Peter V; Löw, Fabian; Newby, Terence; Ferreira, Stefanus; Defourny, Pierre

    2017-01-01

    The lack of sufficient ground truth data has always constrained supervised learning, thereby hindering the generation of up-to-date satellite-derived thematic maps. This is all the more true for those applications requiring frequent updates over large areas such as cropland mapping. Therefore, we present a method enabling the automated production of spatially consistent cropland maps at the national scale, based on spectral-temporal features and outdated land cover information. Following an unsupervised approach, this method extracts reliable calibration pixels based on their labels in the outdated map and their spectral signatures. To ensure spatial consistency and coherence in the map, we first propose to generate seamless input images by normalizing the time series and deriving spectral-temporal features that target salient cropland characteristics. Second, we reduce the spatial variability of the class signatures by stratifying the country and by classifying each stratum independently. Finally, we remove speckle with a weighted majority filter accounting for per-pixel classification confidence. Capitalizing on a wall-to-wall validation data set, the method was tested in South Africa using a 16-year old land cover map and multi-sensor Landsat time series. The overall accuracy of the resulting cropland map reached 92%. A spatially explicit validation revealed large variations across the country and suggests that intensive grain-growing areas were better characterized than smallholder farming systems. Informative features in the classification process vary from one stratum to another but features targeting the minimum of vegetation as well as short-wave infrared features were consistently important throughout the country. Overall, the approach showed potential for routinely delivering consistent cropland maps over large areas as required for operational crop monitoring.

  17. Managing different time granularities of clinical information by an interval-based temporal data model.

    Science.gov (United States)

    Combi, C; Pinciroli, F; Pozzi, G

    1995-12-01

    In the field of databases, time management at different levels of granularity has been an issue for several years, for instance when dealing with clinical information from different databases using different time units, dealing with natural language expressions, or when dealing with temporal uncertainty. A temporal data model is proposed to manage the temporal aspect of data, presented at various and mixed levels of granularity. The concept of temporal assertions shapes the entire temporal information. The model provides a temporal dimension to the data by using intervals that can be specified at different granularities. The model supports a three-valued logic, where True, False and Undefined are the truth values. The temporal data model allows to manage some degrees of uncertainty when establishing temporal relationships between intervals or between temporal assertions, expressed at different granularities. The logical connectives and quantifiers can manage each of the three truth-values. We applied the temporal data model by implementing an object-oriented database system for managing follow-up clinical data from patients who underwent percutaneous transluminal coronary angioplasty.

  18. Vitiligo disease triggers: psychological stressors preceding the onset of disease.

    Science.gov (United States)

    Silverberg, Jonathan I; Silverberg, Nanette B

    2015-05-01

    Vitiligo is the loss of skin pigmentation caused by autoimmune destruction of melanocytes. Little is known about the impact of psychological stressors preceding vitiligo onset on symptoms associated with vitiligo and the extent of disease. We performed a questionnaire-based study of 1541 adults with vitiligo to evaluate the impact of psychological stressors in this patient population. Psychological stressors should be considered as potential disease triggers in vitiligo patients, and screening of vitiligo patients for psychological stressors and associated symptoms should be included in routine assessment.

  19. Using R for analysing spatio-temporal datasets: a satellite-based precipitation case study

    Science.gov (United States)

    Zambrano-Bigiarini, Mauricio

    2017-04-01

    Increasing computer power and the availability of remote-sensing data measuring different environmental variables has led to unprecedented opportunities for Earth sciences in recent decades. However, dealing with hundred or thousands of files, usually in different vectorial and raster formats and measured with different temporal frequencies, impose high computation challenges to take full advantage of all the available data. R is a language and environment for statistical computing and graphics which includes several functions for data manipulation, calculation and graphical display, which are particularly well suited for Earth sciences. In this work I describe how R was used to exhaustively evaluate seven state-of-the-art satellite-based rainfall estimates (SRE) products (TMPA 3B42v7, CHIRPSv2, CMORPH, PERSIANN-CDR, PERSIAN-CCS-adj, MSWEPv1.1 and PGFv3) over the complex topography and diverse climatic gradients of Chile. First, built-in functions were used to automatically download the satellite-images in different raster formats and spatial resolutions and to clip them into the Chilean spatial extent if necessary. Second, the raster package was used to read, plot, and conduct an exploratory data analysis in selected files of each SRE product, in order to detect unexpected problems (rotated spatial domains, order or variables in NetCDF files, etc). Third, raster was used along with the hydroTSM package to aggregate SRE files into different temporal scales (daily, monthly, seasonal, annual). Finally, the hydroTSM and hydroGOF packages were used to carry out a point-to-pixel comparison between precipitation time series measured at 366 stations and the corresponding grid cell of each SRE. The modified Kling-Gupta index of model performance was used to identify possible sources of systematic errors in each SRE, while five categorical indices (PC, POD, FAR, ETS, fBIAS) were used to assess the ability of each SRE to correctly identify different precipitation intensities

  20. Spatio-temporal analysis of brain electrical activity in epilepsy based on cellular nonlinear networks

    Science.gov (United States)

    Gollas, Frank; Tetzlaff, Ronald

    2009-05-01

    Epilepsy is the most common chronic disorder of the nervous system. Generally, epileptic seizures appear without foregoing sign or warning. The problem of detecting a possible pre-seizure state in epilepsy from EEG signals has been addressed by many authors over the past decades. Different approaches of time series analysis of brain electrical activity already are providing valuable insights into the underlying complex dynamics. But the main goal the identification of an impending epileptic seizure with a sufficient specificity and reliability, has not been achieved up to now. An algorithm for a reliable, automated prediction of epileptic seizures would enable the realization of implantable seizure warning devices, which could provide valuable information to the patient and time/event specific drug delivery or possibly a direct electrical nerve stimulation. Cellular Nonlinear Networks (CNN) are promising candidates for future seizure warning devices. CNN are characterized by local couplings of comparatively simple dynamical systems. With this property these networks are well suited to be realized as highly parallel, analog computer chips. Today available CNN hardware realizations exhibit a processing speed in the range of TeraOps combined with low power consumption. In this contribution new algorithms based on the spatio-temporal dynamics of CNN are considered in order to analyze intracranial EEG signals and thus taking into account mutual dependencies between neighboring regions of the brain. In an identification procedure Reaction-Diffusion CNN (RD-CNN) are determined for short segments of brain electrical activity, by means of a supervised parameter optimization. RD-CNN are deduced from Reaction-Diffusion Systems, which usually are applied to investigate complex phenomena like nonlinear wave propagation or pattern formation. The Local Activity Theory provides a necessary condition for emergent behavior in RD-CNN. In comparison linear spatio-temporal

  1. Spatio-Temporal Dynamic Analysis of Sustainable Development in China Based on the Footprint Family.

    Science.gov (United States)

    Zhao, Jing; Ma, Caihong; Zhao, Xiangui; Wang, Xiaoyu

    2018-02-01

    The existing index systems on sustainable evaluation are mostly based on a multi index comprehensive evaluation method. The main disadvantage of this approach is that the selection and assignment of evaluation indexes are greatly influenced by subjective factors, which can result in poor comparability of results. By contrast, the Footprint Family (including ecological footprint, carbon footprint, and water footprint) is not affected by subjective factors. The Footprint Family also covers the basic tenets of sustainable development. This paper proposes use of a sustainable development evaluation index system based on the principle of the Footprint Family, and including the ecological pressure index ( EPI ), the ecological occupancy index ( EOI ), the ecological economic coordination index ( EECI ), the GHG (Greenhouse Gas) emission index ( CEI ), the water resources stress index ( WSI ), and the sustainable development index ( SDI ). Furthermore, a standard for grading the evaluated results based on global benchmarks is formulated. The results of an empirical study in China were the following. The development situation deteriorated from 1990 to 2015. The results showed that the SDI decreased from a medium level (grade 5) to a lower-medium level (grade 4). The results of this empirical study also showed that the method of evaluation can avoid the influence of subjective factors and can be used in the evaluation of sustainable development for various temporal and spatial conditions.

  2. KERNEL-BASED UNSUPERVISED CHANGE DETECTION OF AGRICULTURAL LANDS USING MULTI-TEMPORAL POLARIMETRIC SAR DATA

    Directory of Open Access Journals (Sweden)

    M. A. Fazel

    2013-09-01

    Full Text Available Unsupervised change detection of agricultural lands in seasonal and annual periods is necessary for farming activities and yield estimation. Polarimetric Synthetic Aperture Radar (PolSAR data due to their special characteristics are a powerful source to study temporal behaviour of land cover types. PolSAR data allows building up the powerful observations sensitive to the shape, orientation and dielectric properties of scatterers and allows the development of physical models for identification and separation of scattering mechanisms occurring inside the same region of observed lands. In this paper an unsupervised kernel-based method is introduced for agricultural change detection by PolSAR data. This method works by transforming data into higher dimensional space by kernel functions and clustering them in this space. Kernel based c-means clustering algorithm is employed to separate the changes classes from the no-changes. This method is a non-linear algorithm which considers the contextual information of observations. Using the kernel functions helps to make the non-linear features more separable in a linear space. In addition, use of eigenvectors' parameters as a polarimetric target decomposition technique helps us to consider and benefit physical properties of targets in the PolSAR change detection. Using kernel based c-means clustering with proper initialization of the algorithm makes this approach lead to great results in change detection paradigm.

  3. Single-subject voxel-based relaxometry for clinical assessment of temporal lobe epilepsy.

    Science.gov (United States)

    Kosior, Robert K; Lauzon, M Louis; Frayne, Richard; Federico, Paolo

    2009-09-01

    T2 relaxometry, quantitative assessment of T2 relaxation time in magnetic resonance (MR) data, typically uses manually drawn regions of interest (ROIs). This approach is limited by its subjectivity and its restricted scope of investigation. A recently developed approach called voxel-based relaxometry (VBR) provides an unbiased statistical analysis of the whole brain. Our objective was to assess the clinical utility of single-subject VBR for patients with temporal lobe epilepsy (TLE). Forty-five patients with TLE confirmed by history, EEG, and structural MRI and 25 control subjects were scanned at 3T using a modified Carr-Purcell-Meiboom-Gill MR sequence. ROIs were drawn for each patient and control subject, and measurements were made on unregistered T2 maps. VBR was performed on a single-subject basis at a significance level of alpha=0.05. Patients were grouped according to seizure focus (left mesial, right mesial, other), and whether structural MR imaging was normal or abnormal. Up to 85% of patients in the temporal lobe groups demonstrated T2 abnormalities. VBR detected abnormalities either in equal numbers or in more patients (up to 23% more) than ROI analysis for each group. The number of detected abnormalities per patient was higher using VBR (3.38 versus 2.04, p<0.05). VBR also identified abnormalities that were missed by ROI analysis. The rate of VBR detection of abnormalities was higher for patients than controls (76% versus 36%). VBR can be performed on single subjects with TLE and it detects considerably more abnormalities than ROI analysis. VBR may be a clinically useful tool for the detection of T2 abnormalities at the seizure focus and sites remote from it.

  4. Temporal trends in lipid testing among children and adolescents: A population based study

    Directory of Open Access Journals (Sweden)

    Swetha Sriram

    2017-12-01

    Full Text Available Unfavorable lipid levels during childhood are associated with subsequent development of atherosclerotic cardiovascular disease. The American Academy of Pediatrics and National Heart, Lung and Blood Institute in 2011 recommended universal lipid screening for children between ages 9–11 years and between ages 17–21 years. The objective of the study was to determine temporal trends in lipid testing among children and young adults in a mid-western population. The Rochester Epidemiology Project database was used to identify lipid testing in ages 2–21 years (n = 51,176 in the Olmsted County population from January 1, 2008 through December 31, 2014. Generalized estimating equations with Poisson distribution were used to test for temporal trends in lipid testing across the age groups. There was modest increase in lipid testing in children in the age groups, 9–11 years and 17–21 years (1.5% in 2008 to 2.2% in 2014, P < 0.001 and 4.4% in 2008 to 4.6% in 2014, P = 0.02, respectively. There was a significant decrease in proportion of 17–21 year olds with elevated total cholesterol (16.2% in 2008 to 11.6% in 2014; P = 0.01 and non-high density lipoprotein cholesterol (22.6% in 2008 to 12.6% in 2014; P < 0.001. In this population-based study, rates of lipid testing increased minimally only in the last six years. Further longitudinal studies are warranted to improve guideline dissemination and address attitudes, practices and barriers to lipid testing in children and young adults.

  5. Analysis of spatio-temporal dynamics of Arctic region vegetation based on integrated data processing

    Science.gov (United States)

    Mochalov, Viktor; Zelentsov, Viacheslav; Grigirieva, Olga; Brovkina, Olga; Lavrinenko, Igor; Pimanov, Ilia

    2017-04-01

    Currently, there is a significant amount of in-situ data, airborne and satellite observations for the assessment of tundra vegetation. However, the issues of simultaneous analysis of these data remain topical, as well as the development of methods for integrated processing of heterogeneous (in-situ, airborne, space) and multi-temporal data for analyzing the spatio-temporal dynamics of vegetation across large regions and identifying relationships of occurring changes. The study was aimed to fill this gap on the territory of Russia's Far North. The objectives of the study were: 1/ mapping of vegetation types; 2/ assessing the territories which are suitable for grazing reindeers in winter and summer periods; 3/ substantiation of requirements to remote sensing data for vegetation mapping; and 4/ identification of the territories under anthropogenic disturbances. The study area was located in the Nenets Autonomous Okrug of Russia. Time-series satellite Resurs-P, Kanopus-V and Sentinel-2 data, and geobotanical systematic description of study area were used for classification of vegetation types, identification of vegetation dynamic and disturbed territories. Territory for grazing reindeers were assessed based on map of vegetation types and thirty-year field monitoring of reindeers feed and habitats. The integrated processing of data used in the study was implemented by a complex methodical scheme, which included algorithms and methods for processing of satellite data, requirement to remote sensing data, decision to reduce the cost of data collection and to provide the required level of results quality, and recommendations for management of industrial activity in the Nenets Autonomous Okrug of Russia.

  6. Temporal regularization of ultrasound-based liver motion estimation for image-guided radiation therapy

    Energy Technology Data Exchange (ETDEWEB)

    O’Shea, Tuathan P., E-mail: tuathan.oshea@icr.ac.uk; Bamber, Jeffrey C.; Harris, Emma J. [Joint Department of Physics, The Institute of Cancer Research and The Royal Marsden NHS foundation Trust, Sutton, London SM2 5PT (United Kingdom)

    2016-01-15

    Purpose: Ultrasound-based motion estimation is an expanding subfield of image-guided radiation therapy. Although ultrasound can detect tissue motion that is a fraction of a millimeter, its accuracy is variable. For controlling linear accelerator tracking and gating, ultrasound motion estimates must remain highly accurate throughout the imaging sequence. This study presents a temporal regularization method for correlation-based template matching which aims to improve the accuracy of motion estimates. Methods: Liver ultrasound sequences (15–23 Hz imaging rate, 2.5–5.5 min length) from ten healthy volunteers under free breathing were used. Anatomical features (blood vessels) in each sequence were manually annotated for comparison with normalized cross-correlation based template matching. Five sequences from a Siemens Acuson™ scanner were used for algorithm development (training set). Results from incremental tracking (IT) were compared with a temporal regularization method, which included a highly specific similarity metric and state observer, known as the α–β filter/similarity threshold (ABST). A further five sequences from an Elekta Clarity™ system were used for validation, without alteration of the tracking algorithm (validation set). Results: Overall, the ABST method produced marked improvements in vessel tracking accuracy. For the training set, the mean and 95th percentile (95%) errors (defined as the difference from manual annotations) were 1.6 and 1.4 mm, respectively (compared to 6.2 and 9.1 mm, respectively, for IT). For each sequence, the use of the state observer leads to improvement in the 95% error. For the validation set, the mean and 95% errors for the ABST method were 0.8 and 1.5 mm, respectively. Conclusions: Ultrasound-based motion estimation has potential to monitor liver translation over long time periods with high accuracy. Nonrigid motion (strain) and the quality of the ultrasound data are likely to have an impact on tracking

  7. [Wide QRS tachycardia preceded by pacemaker spikes].

    Science.gov (United States)

    Romero, M; Aranda, A; Gómez, F J; Jurado, A

    2014-04-01

    The differential diagnosis and therapeutic management of wide QRS tachycardia preceded by pacemaker spike is presented. The pacemaker-mediated tachycardia, tachycardia fibrillo-flutter in patients with pacemakers, and runaway pacemakers, have a similar surface electrocardiogram, but respond to different therapeutic measures. The tachycardia response to the application of a magnet over the pacemaker could help in the differential diagnosis, and in some cases will be therapeutic, as in the case of a tachycardia-mediated pacemaker. Although these conditions are diagnosed and treated in hospitals with catheterization laboratories using the application programmer over the pacemaker, patients presenting in primary care clinic and emergency forced us to make a diagnosis and treat the haemodynamically unstable patient prior to referral. Copyright © 2012 Sociedad Española de Médicos de Atención Primaria (SEMERGEN). Publicado por Elsevier España. All rights reserved.

  8. Cognitive declines precede and predict functional declines in aging and Alzheimer's disease.

    Directory of Open Access Journals (Sweden)

    Laura B Zahodne

    Full Text Available To investigate the temporal ordering of cognitive and functional declines separately in older adults with or without Alzheimer's disease (AD.A community-based longitudinal study of aging and dementia in Northern Manhattan (Washington Heights/Hamilton Heights Inwood Columbia Aging Project and a multicenter, clinic-based longitudinal study of prevalent AD at Columbia University Medical Center, Johns Hopkins School of Medicine, Massachusetts General Hospital, and the Hôpital de la Salpêtrière in Paris, France (the Predictors Study.3,443 initially non-demented older adults (612 with eventual incident dementia and 517 patients with AD.Cognitive measures included the modified Mini-Mental State Exam and composite scores of memory and language derived from a standardized neuropsychological battery. Function was measured with the Blessed Dementia Rating Scale, completed by the participant (in the sample of non-demented older adults or an informant (in the sample of prevalent AD patients. Data were analyzed with autoregressive cross-lagged panel analysis.Cognitive scores more consistently predicted subsequent functional abilities than vice versa in non-demented older adults, participants with eventual incident dementia, and patients with prevalent AD.Cognitive declines appear to precede and cause functional declines prior to and following dementia diagnosis. Standardized neuropsychological tests are valid predictors of later functional changes in both non-demented and demented older adults.

  9. Strategic Environmental Assessment Framework for Landscape-Based, Temporal Analysis of Wetland Change in Urban Environments

    Science.gov (United States)

    Sizo, Anton; Noble, Bram F.; Bell, Scott

    2016-03-01

    This paper presents and demonstrates a spatial framework for the application of strategic environmental assessment (SEA) in the context of change analysis for urban wetland environments. The proposed framework is focused on two key stages of the SEA process: scoping and environmental baseline assessment. These stages are arguably the most information-intense phases of SEA and have a significant effect on the quality of the SEA results. The study aims to meet the needs for proactive frameworks to assess and protect wetland habitat and services more efficiently, toward the goal of advancing more intelligent urban planning and development design. The proposed framework, adopting geographic information system and remote sensing tools and applications, supports the temporal evaluation of wetland change and sustainability assessment based on landscape indicator analysis. The framework was applied to a rapidly developing urban environment in the City of Saskatoon, Saskatchewan, Canada, analyzing wetland change and land-use pressures from 1985 to 2011. The SEA spatial scale was rescaled from administrative urban planning units to an ecologically meaningful area. Landscape change assessed was based on a suite of indicators that were subsequently rolled up into a single, multi-dimensional, and easy to understand and communicate index to examine the implications of land-use change for wetland sustainability. The results show that despite the recent extremely wet period in the Canadian prairie region, land-use change contributed to increasing threats to wetland sustainability.

  10. Strategic Environmental Assessment Framework for Landscape-Based, Temporal Analysis of Wetland Change in Urban Environments.

    Science.gov (United States)

    Sizo, Anton; Noble, Bram F; Bell, Scott

    2016-03-01

    This paper presents and demonstrates a spatial framework for the application of strategic environmental assessment (SEA) in the context of change analysis for urban wetland environments. The proposed framework is focused on two key stages of the SEA process: scoping and environmental baseline assessment. These stages are arguably the most information-intense phases of SEA and have a significant effect on the quality of the SEA results. The study aims to meet the needs for proactive frameworks to assess and protect wetland habitat and services more efficiently, toward the goal of advancing more intelligent urban planning and development design. The proposed framework, adopting geographic information system and remote sensing tools and applications, supports the temporal evaluation of wetland change and sustainability assessment based on landscape indicator analysis. The framework was applied to a rapidly developing urban environment in the City of Saskatoon, Saskatchewan, Canada, analyzing wetland change and land-use pressures from 1985 to 2011. The SEA spatial scale was rescaled from administrative urban planning units to an ecologically meaningful area. Landscape change assessed was based on a suite of indicators that were subsequently rolled up into a single, multi-dimensional, and easy to understand and communicate index to examine the implications of land-use change for wetland sustainability. The results show that despite the recent extremely wet period in the Canadian prairie region, land-use change contributed to increasing threats to wetland sustainability.

  11. Clustering-Based Approaches to the Exploration of Spatio-Temporal Data

    Science.gov (United States)

    Wu, X.; Zurita-Milla, R.; Kraak, M.-J.; Izquierdo-Verdiguier, E.

    2017-09-01

    As one spatio-temporal data mining task, clustering helps the exploration of patterns in the data by grouping similar elements together. However, previous studies on spatial or temporal clustering are incapable of analysing complex patterns in spatio-temporal data. For instance, concurrent spatio-temporal patterns in 2D or 3D datasets. In this study we present two clustering algorithms for complex pattern analysis: (1) the Bregman block average co-clustering algorithm with I-divergence (BBAC_I) which enables the concurrent analysis of spatio-temporal patterns in 2D data matrix, and (2) the Bregman cube average tri-clustering algorithm with I-divergence (BCAT_I) which enables the complete partitional analysis in 3D data cube. Here the use of the two clustering algorithms is illustrated by Dutch daily average temperature dataset from 28 weather stations from 1992 to 2011. For BBAC_I, it is applied to the averaged yearly dataset to identify station-year co-clusters which contain similar temperatures along stations and years, thus revealing patterns along both spatial and temporal dimensions. For BCAT_I, it is applied to the temperature dataset organized in a data cube with one spatial (stations) and two nested temporal dimensions (years and days). By partitioning the whole dataset into clusters of stations and years with similar within-year temperature similarity, BCATI explores the spatio-temporal patterns of intra-annual variability in the daily temperature dataset. As such, both BBACI and BCATI algorithms, combined with suitable geovisualization techniques, allow the exploration of complex spatial and temporal patterns, which contributes to a better understanding of complex patterns in spatio-temporal data.

  12. Spatial attention is necessary for object-based attention: Evidence from temporal-order judgments.

    Science.gov (United States)

    Donovan, Ian; Pratt, Jay; Shomstein, Sarah

    2017-04-01

    Attentional selection is a dynamic process that relies on multiple types of representations. That object representations contribute to attentional selection has been known for decades; however, most evidence for this contribution has been gleaned from studies that have relied on various forms of spatial cueing (some endogenous and some exogenous). It has thus remained unclear whether object-based attentional selection is a direct result of spatial cuing, or whether it still emerges without any spatial marker. Here we used a novel method-the temporal-order judgment (TOJ)-to examine whether object-based guidance emerges in the absence of spatial cuing. Participants were presented with two rectangles oriented either horizontally or vertically. Following a 150-ms preview time, two target stimuli were presented on the same or on different objects, and participants were asked to report which of the two stimuli had appeared first. The targets consisted of stimuli that formed a percept of a "hole" or a "hill." First, we demonstrated that the "hill" target was indeed processed faster, as evidenced by a positive perceived simultaneity (PSS) measure. We then demonstrated that if two targets appeared with equal probabilities on the same and on different objects, the PSS values, although positive, were not modulated by the objects. In a subsequent set of experiments, we showed that objects can modulate attentional allocation-however, only when they are biased by a spatial (endogenous) cue. In other words, in the absence of a spatial cue or bias, object representations do not guide attentional selection. In addition to providing new constraints for theories of object-based attentional guidance, these experiments introduce a novel paradigm for measuring object-based attentional effects.

  13. Merging multimedia presentations and semistructured temporal data: a graph-based model and its application to clinical information.

    Science.gov (United States)

    Combi, Carlo; Oliboni, Barbara; Rossato, Rosalba

    2005-06-01

    In this paper, we focus on the issue of providing physicians with the capability of representing in a seamless way both temporal aspects of multimedia semistructured data and their temporal presentation requirements. Semistructured data are data having some structure, that may be irregular or incomplete and does not necessarily conform to a fixed schema. Semistructured data often contain the description of histories of the considered real world. The eXtensible Markup Language (XML) is becoming a cross compatible and standardized means for representing semistructured clinical data. In the field of medical informatics, there are many ongoing activities concerning XML. In the field of multimedia database systems, the topic related to the integration of several media objects (with their temporal aspects) have been considered both for data modeling and querying issues and for modeling multimedia presentations. We first propose the Multimedia Temporal Graphical Model (MTGM), by representing a clinical database for cardiology patients undergoing cardiac angiographies and then describe it in a formal way. We deal with the problem of expressing MTGM data by XML and of managing MTGM clinical data through an XML-based system. We provide both a technique for translating (a part of) an MTGM database into an XML document and some techniques allowing us to obtain presentations defined by means of the Synchronized Multimedia Integration Language (SMIL) from MTGM presentations. MTGM allows one to represent and store clinical information in a semistructured, temporal, and multimedia database. The physician can define multimedia presentations based on the stored data. Multimedia presentations are then stored in the same MTGM database together with temporal clinical information and are thus represented according to the same data model. A prototype based on an XML native database system has been designed and implemented. In this work we have considered the theoretical and

  14. Laser-based terahertz-field-driven streak camera for the temporal characterization of ultrashort processes

    Energy Technology Data Exchange (ETDEWEB)

    Schuette, Bernd

    2011-09-15

    In this work, a novel laser-based terahertz-field-driven streak camera is presented. It allows for a pulse length characterization of femtosecond (fs) extreme ultraviolet (XUV) pulses by a cross-correlation with terahertz (THz) pulses generated with a Ti:sapphire laser. The XUV pulses are emitted by a source of high-order harmonic generation (HHG) in which an intense near-infrared (NIR) fs laser pulse is focused into a gaseous medium. The design and characterization of a high-intensity THz source needed for the streak camera is also part of this thesis. The source is based on optical rectification of the same NIR laser pulse in a lithium niobate crystal. For this purpose, the pulse front of the NIR beam is tilted via a diffraction grating to achieve velocity matching between NIR and THz beams within the crystal. For the temporal characterization of the XUV pulses, both HHG and THz beams are focused onto a gas target. The harmonic radiation creates photoelectron wavepackets which are then accelerated by the THz field depending on its phase at the time of ionization. This principle adopted from a conventional streak camera and now widely used in attosecond metrology. The streak camera presented here is an advancement of a terahertz-field-driven streak camera implemented at the Free Electron Laser in Hamburg (FLASH). The advantages of the laser-based streak camera lie in its compactness, cost efficiency and accessibility, while providing the same good quality of measurements as obtained at FLASH. In addition, its flexibility allows for a systematic investigation of streaked Auger spectra which is presented in this thesis. With its fs time resolution, the terahertz-field-driven streak camera thereby bridges the gap between attosecond and conventional cameras. (orig.)

  15. Extension of the preceding birth technique.

    Science.gov (United States)

    Aguirre, A

    1994-01-01

    The Brass-inspired Preceding Birth Technique (PBT), is an indirect estimation technique with low costs of administration. PBT involves asking women at a time close to delivery about the survival of the preceding births. The proportion dead is close to the probability of dying between the birth and the second birthday or an index of early childhood mortality (II or Q). Brass and Macrae have determined that II is an estimate of mortality between birth and an age lower than the birth interval or around 4/5 of the birth interval. Hospital and clinic data are likely to include a concentration of women with lower risks of disease because of higher educational levels and socioeconomic status. A simulation of PBT data from the World Fertility Survey for Mexico and Peru found that the proportions of previously dead children were 0.156 in Peru and 0.092 in Mexican home deliveries. Maternity clinic proportions were 0.088 in Peru and 0.066 in Mexico. Use of clinic and hospital data collection underestimated mortality by 32% in Peru and 15% in Mexico. Another alternative was proposed: interviewing women at some other time than delivery. If the interview was during a child/infant intervention after delivery, the subsample would still be subject to a bias, but this problem could be overcome by computing the weighted average of the actual probability of the older child being dead and the conditional probability of the younger child being dead or both younger and older children being dead. Correction factors could be applied using the general standard of the logit life table system of Brass. Calculation of a simple average of the ages of the younger children could provide enough information to help decide which tables to use. Five surveys were selected for testing the factors of dependence between probabilities of death of successive siblings: Bangladesh, Lesotho, Kenya, Ghana, and Guyana. Higher mortality was related to lower dependency factors between the probabilities of death

  16. Exact and Heuristic Algorithms for Routing AGV on Path with Precedence Constraints

    Directory of Open Access Journals (Sweden)

    Liang Xu

    2016-01-01

    Full Text Available A new problem arises when an automated guided vehicle (AGV is dispatched to visit a set of customers, which are usually located along a fixed wire transmitting signal to navigate the AGV. An optimal visiting sequence is desired with the objective of minimizing the total travelling distance (or time. When precedence constraints are restricted on customers, the problem is referred to as traveling salesman problem on path with precedence constraints (TSPP-PC. Whether or not it is NP-complete has no answer in the literature. In this paper, we design dynamic programming for the TSPP-PC, which is the first polynomial-time exact algorithm when the number of precedence constraints is a constant. For the problem with number of precedence constraints, part of the input can be arbitrarily large, so we provide an efficient heuristic based on the exact algorithm.

  17. Non-auditory, electrophysiological potentials preceding dolphin biosonar click production.

    Science.gov (United States)

    Finneran, James J; Mulsow, Jason; Jones, Ryan; Houser, Dorian S; Accomando, Alyssa W; Ridgway, Sam H

    2018-03-01

    The auditory brainstem response to a dolphin's own emitted biosonar click can be measured by averaging epochs of the instantaneous electroencephalogram (EEG) that are time-locked to the emitted click. In this study, averaged EEGs were measured using surface electrodes placed on the head in six different configurations while dolphins performed an echolocation task. Simultaneously, biosonar click emissions were measured using contact hydrophones on the melon and a hydrophone in the farfield. The averaged EEGs revealed an electrophysiological potential (the pre-auditory wave, PAW) that preceded the production of each biosonar click. The largest PAW amplitudes occurred with the non-inverting electrode just right of the midline-the apparent side of biosonar click generation-and posterior of the blowhole. Although the source of the PAW is unknown, the temporal and spatial properties rule out an auditory source. The PAW may be a neural or myogenic potential associated with click production; however, it is not known if muscles within the dolphin nasal system can be actuated at the high rates reported for dolphin click production, or if sufficiently coordinated and fast motor endplates of nasal muscles exist to produce a PAW detectable with surface electrodes.

  18. Directional velocity estimation using a spatio-temporal encoding technique based on frequency division for synthetic transmit aperture ultrasound

    DEFF Research Database (Denmark)

    Gran, Fredrik; Jensen, Jørgen Arendt

    2006-01-01

    This paper investigates the possibility of flow estimation using spatio-temporal encoding of the transmissions in synthetic transmit aperture imaging (STA). The spatial encoding is based on a frequency division approach. In STA, a major disadvantage is that only a single transmitter (denoting sin...

  19. Geo-Parcel Based Crop Identification by Integrating High Spatial-Temporal Resolution Imagery from Multi-Source Satellite Data

    Directory of Open Access Journals (Sweden)

    Yingpin Yang

    2017-12-01

    Full Text Available Geo-parcel based crop identification plays an important role in precision agriculture. It meets the needs of refined farmland management. This study presents an improved identification procedure for geo-parcel based crop identification by combining fine-resolution images and multi-source medium-resolution images. GF-2 images with fine spatial resolution of 0.8 m provided agricultural farming plot boundaries, and GF-1 (16 m and Landsat 8 OLI data were used to transform the geo-parcel based enhanced vegetation index (EVI time-series. In this study, we propose a piecewise EVI time-series smoothing method to fit irregular time profiles, especially for crop rotation situations. Global EVI time-series were divided into several temporal segments, from which phenological metrics could be derived. This method was applied to Lixian, where crop rotation was the common practice of growing different types of crops, in the same plot, in sequenced seasons. After collection of phenological features and multi-temporal spectral information, Random Forest (RF was performed to classify crop types, and the overall accuracy was 93.27%. Moreover, an analysis of feature significance showed that phenological features were of greater importance for distinguishing agricultural land cover compared to temporal spectral information. The identification results indicated that the integration of high spatial-temporal resolution imagery is promising for geo-parcel based crop identification and that the newly proposed smoothing method is effective.

  20. Spatial-temporal-covariance-based modeling, analysis, and simulation of aero-optics wavefront aberrations.

    Science.gov (United States)

    Vogel, Curtis R; Tyler, Glenn A; Wittich, Donald J

    2014-07-01

    We introduce a framework for modeling, analysis, and simulation of aero-optics wavefront aberrations that is based on spatial-temporal covariance matrices extracted from wavefront sensor measurements. Within this framework, we present a quasi-homogeneous structure function to analyze nonhomogeneous, mildly anisotropic spatial random processes, and we use this structure function to show that phase aberrations arising in aero-optics are, for an important range of operating parameters, locally Kolmogorov. This strongly suggests that the d5/3 power law for adaptive optics (AO) deformable mirror fitting error, where d denotes actuator separation, holds for certain important aero-optics scenarios. This framework also allows us to compute bounds on AO servo lag error and predictive control error. In addition, it provides us with the means to accurately simulate AO systems for the mitigation of aero-effects, and it may provide insight into underlying physical processes associated with turbulent flow. The techniques introduced here are demonstrated using data obtained from the Airborne Aero-Optics Laboratory.

  1. Global rainfall erosivity assessment based on high-temporal resolution rainfall records.

    Science.gov (United States)

    Panagos, Panos; Borrelli, Pasquale; Meusburger, Katrin; Yu, Bofu; Klik, Andreas; Jae Lim, Kyoung; Yang, Jae E; Ni, Jinren; Miao, Chiyuan; Chattopadhyay, Nabansu; Sadeghi, Seyed Hamidreza; Hazbavi, Zeinab; Zabihi, Mohsen; Larionov, Gennady A; Krasnov, Sergey F; Gorobets, Andrey V; Levi, Yoav; Erpul, Gunay; Birkel, Christian; Hoyos, Natalia; Naipal, Victoria; Oliveira, Paulo Tarso S; Bonilla, Carlos A; Meddi, Mohamed; Nel, Werner; Al Dashti, Hassan; Boni, Martino; Diodato, Nazzareno; Van Oost, Kristof; Nearing, Mark; Ballabio, Cristiano

    2017-06-23

    The exposure of the Earth's surface to the energetic input of rainfall is one of the key factors controlling water erosion. While water erosion is identified as the most serious cause of soil degradation globally, global patterns of rainfall erosivity remain poorly quantified and estimates have large uncertainties. This hampers the implementation of effective soil degradation mitigation and restoration strategies. Quantifying rainfall erosivity is challenging as it requires high temporal resolution(<30 min) and high fidelity rainfall recordings. We present the results of an extensive global data collection effort whereby we estimated rainfall erosivity for 3,625 stations covering 63 countries. This first ever Global Rainfall Erosivity Database was used to develop a global erosivity map at 30 arc-seconds(~1 km) based on a Gaussian Process Regression(GPR). Globally, the mean rainfall erosivity was estimated to be 2,190 MJ mm ha-1 h-1 yr-1, with the highest values in South America and the Caribbean countries, Central east Africa and South east Asia. The lowest values are mainly found in Canada, the Russian Federation, Northern Europe, Northern Africa and the Middle East. The tropical climate zone has the highest mean rainfall erosivity followed by the temperate whereas the lowest mean was estimated in the cold climate zone.

  2. A Temporal Credential-Based Mutual Authentication with Multiple-Password Scheme for Wireless Sensor Networks.

    Science.gov (United States)

    Liu, Xin; Zhang, Ruisheng; Liu, Qidong

    2017-01-01

    Wireless sensor networks (WSNs), which consist of a large number of sensor nodes, have become among the most important technologies in numerous fields, such as environmental monitoring, military surveillance, control systems in nuclear reactors, vehicle safety systems, and medical monitoring. The most serious drawback for the widespread application of WSNs is the lack of security. Given the resource limitation of WSNs, traditional security schemes are unsuitable. Approaches toward withstanding related attacks with small overhead have thus recently been studied by many researchers. Numerous studies have focused on the authentication scheme for WSNs, but most of these works cannot achieve the security performance and overhead perfectly. Nam et al. proposed a two-factor authentication scheme with lightweight sensor computation for WSNs. In this paper, we review this scheme, emphasize its drawbacks, and propose a temporal credential-based mutual authentication with a multiple-password scheme for WSNs. Our scheme uses multiple passwords to achieve three-factor security performance and generate a session key between user and sensor nodes. The security analysis phase shows that our scheme can withstand related attacks, including a lost password threat, and the comparison phase shows that our scheme involves a relatively small overhead. In the comparison of the overhead phase, the result indicates that more than 95% of the overhead is composed of communication and not computation overhead. Therefore, the result motivates us to pay further attention to communication overhead than computation overhead in future research.

  3. Spatio-temporal pharmacokinetic model based registration of 4D PET neuroimaging data.

    Science.gov (United States)

    Jiao, Jieqing; Searle, Graham E; Tziortzi, Andri C; Salinas, Cristian A; Gunn, Roger N; Schnabel, Julia A

    2014-01-01

    In dynamic positron emission tomography (PET) neuroimaging studies, where scan durations often exceed 1h, registration of motion-corrupted dynamic PET images is necessary in order to maintain the integrity of the physiological, pharmacological, or biochemical information derived from the tracer kinetic analysis of the scan. In this work, we incorporate a pharmacokinetic model, which is traditionally used to analyse PET data following any registration, into the registration process itself in order to allow for a groupwise registration of the temporal time frames. The new method is shown to achieve smaller registration errors and improved kinetic parameter estimates on validation data sets when compared with image similarity based registration approaches. When applied to measured clinical data from 10 healthy subjects scanned with [(11)C]-(+)-PHNO (a dopamine D3/D2 receptor tracer), it reduces the intra-class variability on the receptor binding outcome measure, further supporting the improvements in registration accuracy. Our method incorporates a generic tracer kinetic model which makes it applicable to different PET radiotracers to remove motion artefacts and increase the integrity of dynamic PET studies. © 2013.

  4. Temporal and spatial characteristics of water resources in the Yeerqiang River Basin based on remote sensing

    Science.gov (United States)

    Y Ran, Q.; Y Bai, L.; Feng, J. Z.; Yang, Y. M.; Guo, M. Q.; Li, H. L.; Zhang, Q.; Zhang, P.; Cao, D.

    2017-07-01

    Surface water resources play an important role in the economic and social developments as well as the protection of natural ecological environment in the Yeerqiang River Basin. Based upon the six stages of land use data from 1990 to 2015, the temporal and spatial variation of surface water resources in the Yerqiang River Basin have been explored and analyzed. The results show that: (1) From 1990 to 2015, the area of natural landscape initially increased and then decreased, while the area of artificial landscape increased, which caused a slight increase in the land use degree in the study area. (2) The dynamic changes of water and glacier areas are somewhat consistent over the past 25 years, with a sharp decline between 2005-2010 and a small increase in the remaining years. The dynamic changes in areas of non-glacial water were moderate, with decrease in area of 9 km2 from 1990 to 2015. The beach area decreased, and the other water sub-classes initially increased and then decreased. (3) Over the past 25 years, the proportion of unchanged water area is 73.22%, the transfer-out proportion is 19.19%, and the transfer-in proportion is 7.59%. Generally, water types transferred to grassland and unused land. Additionally, significant transfers were observed for the conversions between glaciers and woodland, conversions between canal, lake, reservoir and beach, and conversions between beach and farmland.

  5. Temporal Trends in the Incidence and Natural History of Diverticulitis: A Population-Based Study

    Science.gov (United States)

    Bharucha, Adil E.; Parthasarathy, Gopanandan; Ditah, Ivo; Fletcher, J. G.; Ewelukwa, Ofor; Pendlimari, Rajesh; Yawn, Barbara P.; Melton, L. Joseph; Schleck, Cathy; Zinsmeister, Alan R.

    2015-01-01

    Background & Aims Data on the incidence and natural history of diverticulitis are largely hospital-based and exclude the majority of diverticulitis patients, who are treated in an outpatient setting for uncomplicated diverticulitis. We assessed temporal trends in the epidemiology of diverticulitis in the general population. Methods Through the Rochester Epidemiology Project we reviewed the records of all individuals with a diagnosis of diverticulitis from 1980–2007 in Olmsted County, Minnesota. Results In 1980–1989 the incidence of diverticulitis was 115/100,000 person-years, which increased to 188/100,000 in 2000–2007 (Pdiverticulitis episodes, 22% and 55% had a recurrence, respectively. This recurrence rate was greater in younger people (hazard ratio [HR] per decade 0.63; 95% confidence interval [CI], 0.59–0.66) and women (HR 0.68; 95% CI, 0.58–0.80). Complications were seen in 12%; this rate did not change over time. Recurrent diverticulitis was associated with a decreased risk of complications (Pdiverticulitis was lower in older people (Pdiverticulitis did not change from 1980–2007. Conclusions The incidence of diverticulitis has increased by 50% in 2000–2007 compared to 1990–1999, and more so in younger people. Complications are relatively uncommon. Recurrent diverticulitis is frequent but typically uncomplicated. Younger people with diverticulitis had less severe disease, more recurrence, and better survival. PMID:26416187

  6. Mesial temporal lobe epilepsy lateralization using SPHARM-based features of hippocampus and SVM

    Science.gov (United States)

    Esmaeilzadeh, Mohammad; Soltanian-Zadeh, Hamid; Jafari-Khouzani, Kourosh

    2012-02-01

    This paper improves the Lateralization (identification of the epileptogenic hippocampus) accuracy in Mesial Temporal Lobe Epilepsy (mTLE). In patients with this kind of epilepsy, usually one of the brain's hippocampi is the focus of the epileptic seizures, and resection of the seizure focus is the ultimate treatment to control or reduce the seizures. Moreover, the epileptogenic hippocampus is prone to shrinkage and deformation; therefore, shape analysis of the hippocampus is advantageous in the preoperative assessment for the Lateralization. The method utilized for shape analysis is the Spherical Harmonics (SPHARM). In this method, the shape of interest is decomposed using a set of bases functions and the obtained coefficients of expansion are the features describing the shape. To perform shape comparison and analysis, some pre- and post-processing steps such as "alignment of different subjects' hippocampi" and the "reduction of feature-space dimension" are required. To this end, first order ellipsoid is used for alignment. For dimension reduction, we propose to keep only the SPHARM coefficients with maximum conformity to the hippocampus shape. Then, using these coefficients of normal and epileptic subjects along with 3D invariants, specific lateralization indices are proposed. Consequently, the 1536 SPHARM coefficients of each subject are summarized into 3 indices, where for each index the negative (positive) value shows that the left (right) hippocampus is deformed (diseased). Employing these indices, the best achieved lateralization accuracy for clustering and classification algorithms are 85% and 92%, respectively. This is a significant improvement compared to the conventional volumetric method.

  7. Rapid assessment of large scale vegetation change based on multi-temporal phenological analysis

    Science.gov (United States)

    Cai, Danlu; Guan, Yanning; Guo, Shan; Yan, Baoping; Xing, Zhi; Zhang, Chunyan; Piao, Yingchao; An, Xudong; Kang, Lihua

    2011-11-01

    Detecting vegetation change is critical for earth system and sustainability science. The existing methods, however, show several limitations, including inevitable selection of imagery acquisition dates, affection from vegetation related noise on temporal trajectory analysis, and assumptions due to vegetation classification model. This paper presents a multitemporal phenological frequency analysis over a relatively short period (MTPFA-SP) methodology to detect vegetation changes. This MTPFA-SP methodology bases on the amplitude components of fast Fourier transforming (FFT) and is implemented with two steps. First, NDVI time series over two periods are transformed with FFT into frequency domain, separately. Second, amplitude components with phenological information from Step 1 are selected for further change comparison. In this methodology, component selection shows physical meanings of natural vegetation process in frequency domain. Comparisons among those selected components help enhance the ability to rapidly detect vegetation changes. To validate this MTPFA-SP methodology, we detect changes between two periods (2001-2005 and 2006-2010) in the eastern Tibet Plateau area and make two kinds of assessments. The first is for a larger scale, including statistic analysis of altitudinal zonality and latitudinal zonality. The second assessment is for rapid detection of vegetation change location. Landsat TM image were employed to validate the result.

  8. Tracing the Spatial-Temporal Evolution of Events Based on Social Media Data

    Directory of Open Access Journals (Sweden)

    Xiaolu Zhou

    2017-03-01

    Full Text Available Social media data provide a great opportunity to investigate event flow in cities. Despite the advantages of social media data in these investigations, the data heterogeneity and big data size pose challenges to researchers seeking to identify useful information about events from the raw data. In addition, few studies have used social media posts to capture how events develop in space and time. This paper demonstrates an efficient approach based on machine learning and geovisualization to identify events and trace the development of these events in real-time. We conducted an empirical study to delineate the temporal and spatial evolution of a natural event (heavy precipitation and a social event (Pope Francis’ visit to the US in the New York City—Washington, DC regions. By investigating multiple features of Twitter data (message, author, time, and geographic location information, this paper demonstrates how voluntary local knowledge from tweets can be used to depict city dynamics, discover spatiotemporal characteristics of events, and convey real-time information.

  9. Traffic Video Image Segmentation Model Based on Bayesian and Spatio-Temporal Markov Random Field

    Science.gov (United States)

    Zhou, Jun; Bao, Xu; Li, Dawei; Yin, Yongwen

    2017-10-01

    Traffic video image is a kind of dynamic image and its background and foreground is changed at any time, which results in the occlusion. In this case, using the general method is more difficult to get accurate image segmentation. A segmentation algorithm based on Bayesian and Spatio-Temporal Markov Random Field is put forward, which respectively build the energy function model of observation field and label field to motion sequence image with Markov property, then according to Bayesian' rule, use the interaction of label field and observation field, that is the relationship of label field’s prior probability and observation field’s likelihood probability, get the maximum posterior probability of label field’s estimation parameter, use the ICM model to extract the motion object, consequently the process of segmentation is finished. Finally, the segmentation methods of ST - MRF and the Bayesian combined with ST - MRF were analyzed. Experimental results: the segmentation time in Bayesian combined with ST-MRF algorithm is shorter than in ST-MRF, and the computing workload is small, especially in the heavy traffic dynamic scenes the method also can achieve better segmentation effect.

  10. Spatio-temporal Analysis of suspended sediment Concentration in the Yongjiang Estuary Based on GOCI

    Science.gov (United States)

    Kang, Yanyan; Dong, Chuan

    2018-01-01

    The concentration and spatio-temporal variation of suspended sediment concentration in the estuary area are of great significance to the nearshore engineering, port construction and coastal evolution. Based on multi-period GOCI images and corresponding measured suspended sediment concentration (SSC) data, three inversion models (the linear regression model, the power exponent model and the neural network model) were established after rapid atmospheric correction. The results show that the absolute error of the three models is 0.20, 0.16 and 0.10kg/m3 respectively, and the relative errors are 38%, 23% and 18% respectively. The accuracy of the neural network (8-17-17-1) is the best. The SSC distribution diagrams in an ebb and flow cycle are obtained using this ANN model. The results show that with Yongjiang estuary for segmentation, the high concentration area is located in the north and the lower is in the south around Jintang Island deeper water area. When the tide rises, the water flow disturbs a large amount of sediment, and then the sediment concentration increases and high area high concentrations water body moves along the SE-NW. When the tide falls, flow rate decreases and the sediment concentration decreases. However, with the falling tide, the concentration of suspended sediment in the northern sea areas gradually increases, and is higher than 1kg/m3, and gradually moves along the NW-SE until to the estuary.

  11. Temporal focusing-based widefield multiphoton microscopy with spatially modulated illumination for biotissue imaging.

    Science.gov (United States)

    Chang, Chia-Yuan; Lin, Cheng-Han; Lin, Chun-Yu; Sie, Yong-Da; Hu, Yvonne Yuling; Tsai, Sheng-Feng; Chen, Shean-Jen

    2017-05-02

    A developed temporal focusing-based multiphoton excitation microscope (TFMPEM) has a digital micromirror device (DMD) which is adopted not only as a blazed grating for light spatial dispersion but also for patterned illumination simultaneously. Herein, the TFMPEM has been extended to implement spatially modulated illumination at structured frequency and orientation to increase the beam coverage at the back-focal aperture of the objective lens. The axial excitation confinement (AEC) of TFMPEM can be condensed from 3.0 μm to 1.5 μm for a 50 % improvement. By using the TFMPEM with HiLo technique as two structured illuminations at the same spatial frequency but different orientation, reconstructed biotissue images according to the condensed AEC structured illumination are shown obviously superior in contrast and better scattering suppression. Picture: TPEF images of the eosin-stained mouse cerebellar cortex by conventional TFMPEM (left), and the TFMPEM with HiLo technique as 1.09 μm-1 spatially modulated illumination at 90° (center) and 0° (right) orientations. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Amyloid plaque formation precedes dendritic spine loss.

    Science.gov (United States)

    Bittner, Tobias; Burgold, Steffen; Dorostkar, Mario M; Fuhrmann, Martin; Wegenast-Braun, Bettina M; Schmidt, Boris; Kretzschmar, Hans; Herms, Jochen

    2012-12-01

    Amyloid-beta plaque deposition represents a major neuropathological hallmark of Alzheimer's disease. While numerous studies have described dendritic spine loss in proximity to plaques, much less is known about the kinetics of these processes. In particular, the question as to whether synapse loss precedes or follows plaque formation remains unanswered. To address this question, and to learn more about the underlying kinetics, we simultaneously imaged amyloid plaque deposition and dendritic spine loss by applying two-photon in vivo microscopy through a cranial window in double transgenic APPPS1 mice. As a result, we first observed that the rate of dendritic spine loss in proximity to plaques is the same in both young and aged animals. However, plaque size only increased significantly in the young cohort, indicating that spine loss persists even many months after initial plaque appearance. Tracking the fate of individual spines revealed that net spine loss is caused by increased spine elimination, with the rate of spine formation remaining constant. Imaging of dendritic spines before and during plaque formation demonstrated that spine loss around plaques commences at least 4 weeks after initial plaque formation. In conclusion, spine loss occurs, shortly but with a significant time delay, after the birth of new plaques, and persists in the vicinity of amyloid plaques over many months. These findings hence give further hope to the possibility that there is a therapeutic window between initial amyloid plaque deposition and the onset of structural damage at spines.

  13. Obligate progression precedes lung adenocarcinoma dissemination.

    Science.gov (United States)

    Caswell, Deborah R; Chuang, Chen-Hua; Yang, Dian; Chiou, Shin-Heng; Cheemalavagu, Shashank; Kim-Kiselak, Caroline; Connolly, Andrew; Winslow, Monte M

    2014-07-01

    Despite its clinical importance, very little is known about the natural history and molecular underpinnings of lung cancer dissemination and metastasis. Here, we used a genetically engineered mouse model of metastatic lung adenocarcinoma in which cancer cells are fluorescently marked to determine whether dissemination is an inherent ability or a major acquired phenotype during lung adenocarcinoma metastasis. We find very little evidence for dissemination from oncogenic KRAS-driven hyperplasias or most adenocarcinomas. p53 loss is insufficient to drive dissemination but rather enables rare cancer cells in a small fraction of primary adenocarcinomas to gain alterations that drive dissemination. Molecular characterization of disseminated tumor cells indicates that downregulation of the transcription factor Nkx2-1 precedes dissemination. Finally, we show that metastatic primary tumors possess a highly proliferative subpopulation of cells with characteristics matching those of disseminating cells. We propose that dissemination is a major hurdle during the natural course of lung adenocarcinoma metastasis. Because of its aggressively metastatic nature, lung cancer is the top cancer killer of both men and women in the United States. We show that, unlike in other cancer types, lung cancer dissemination is a major initial barrier to metastasis. Our findings provide insight into the effect of p53 deficiency and downregulation of Nkx2-1 during lung adenocarcinoma progression. ©2014 American Association for Cancer Research.

  14. Modelling Temporal Schedule of Urban Trains Using Agent-Based Simulation and NSGA2-BASED Multiobjective Optimization Approaches

    Science.gov (United States)

    Sahelgozin, M.; Alimohammadi, A.

    2015-12-01

    Increasing distances between locations of residence and services leads to a large number of daily commutes in urban areas. Developing subway systems has been taken into consideration of transportation managers as a response to this huge amount of travel demands. In developments of subway infrastructures, representing a temporal schedule for trains is an important task; because an appropriately designed timetable decreases Total passenger travel times, Total Operation Costs and Energy Consumption of trains. Since these variables are not positively correlated, subway scheduling is considered as a multi-criteria optimization problem. Therefore, proposing a proper solution for subway scheduling has been always a controversial issue. On the other hand, research on a phenomenon requires a summarized representation of the real world that is known as Model. In this study, it is attempted to model temporal schedule of urban trains that can be applied in Multi-Criteria Subway Schedule Optimization (MCSSO) problems. At first, a conceptual framework is represented for MCSSO. Then, an agent-based simulation environment is implemented to perform Sensitivity Analysis (SA) that is used to extract the interrelations between the framework components. These interrelations is then taken into account in order to construct the proposed model. In order to evaluate performance of the model in MCSSO problems, Tehran subway line no. 1 is considered as the case study. Results of the study show that the model was able to generate an acceptable distribution of Pareto-optimal solutions which are applicable in the real situations while solving a MCSSO is the goal. Also, the accuracy of the model in representing the operation of subway systems was significant.

  15. MODELLING TEMPORAL SCHEDULE OF URBAN TRAINS USING AGENT-BASED SIMULATION AND NSGA2-BASED MULTIOBJECTIVE OPTIMIZATION APPROACHES

    Directory of Open Access Journals (Sweden)

    M. Sahelgozin

    2015-12-01

    Full Text Available Increasing distances between locations of residence and services leads to a large number of daily commutes in urban areas. Developing subway systems has been taken into consideration of transportation managers as a response to this huge amount of travel demands. In developments of subway infrastructures, representing a temporal schedule for trains is an important task; because an appropriately designed timetable decreases Total passenger travel times, Total Operation Costs and Energy Consumption of trains. Since these variables are not positively correlated, subway scheduling is considered as a multi-criteria optimization problem. Therefore, proposing a proper solution for subway scheduling has been always a controversial issue. On the other hand, research on a phenomenon requires a summarized representation of the real world that is known as Model. In this study, it is attempted to model temporal schedule of urban trains that can be applied in Multi-Criteria Subway Schedule Optimization (MCSSO problems. At first, a conceptual framework is represented for MCSSO. Then, an agent-based simulation environment is implemented to perform Sensitivity Analysis (SA that is used to extract the interrelations between the framework components. These interrelations is then taken into account in order to construct the proposed model. In order to evaluate performance of the model in MCSSO problems, Tehran subway line no. 1 is considered as the case study. Results of the study show that the model was able to generate an acceptable distribution of Pareto-optimal solutions which are applicable in the real situations while solving a MCSSO is the goal. Also, the accuracy of the model in representing the operation of subway systems was significant.

  16. Automated Discovery and Modeling of Sequential Patterns Preceding Events of Interest

    Science.gov (United States)

    Rohloff, Kurt

    2010-01-01

    The integration of emerging data manipulation technologies has enabled a paradigm shift in practitioners' abilities to understand and anticipate events of interest in complex systems. Example events of interest include outbreaks of socio-political violence in nation-states. Rather than relying on human-centric modeling efforts that are limited by the availability of SMEs, automated data processing technologies has enabled the development of innovative automated complex system modeling and predictive analysis technologies. We introduce one such emerging modeling technology - the sequential pattern methodology. We have applied the sequential pattern methodology to automatically identify patterns of observed behavior that precede outbreaks of socio-political violence such as riots, rebellions and coups in nation-states. The sequential pattern methodology is a groundbreaking approach to automated complex system model discovery because it generates easily interpretable patterns based on direct observations of sampled factor data for a deeper understanding of societal behaviors that is tolerant of observation noise and missing data. The discovered patterns are simple to interpret and mimic human's identifications of observed trends in temporal data. Discovered patterns also provide an automated forecasting ability: we discuss an example of using discovered patterns coupled with a rich data environment to forecast various types of socio-political violence in nation-states.

  17. Gray matter changes in right superior temporal gyrus in criminal psychopaths. Evidence from voxel-based morphometry.

    Science.gov (United States)

    Müller, Jürgen L; Gänssbauer, Susanne; Sommer, Monika; Döhnel, Katrin; Weber, Tatjana; Schmidt-Wilcke, Tobias; Hajak, Göran

    2008-08-30

    "Psychopathy" according to the PCL-R describes a specific subgroup of antisocial personality disorder with a high risk for criminal relapses. Lesion and imaging studies point towards frontal or temporal brain regions connected with disturbed social behavior, antisocial personality disorder (APD) and psychopathy. Morphologically, some studies described a reduced prefrontal brain volume, whereas others reported on temporal lobe atrophy. To further investigate whether participants with psychopathy according to the Psychopathy Checklist-Revised Version (PCL-R) show abnormalities in brain structure, we used voxel-based morphometry (VBM) to investigate region-specific changes in gray matter in 17 forensic male inpatients with high PCL-R scores (PCL-R>28) and 17 male control subjects with low PCL-R scores (PCLright superior temporal gyrus. This is the first study to show that psychopathy is associated with a decrease in gray matter in both frontal and temporal brain regions, in particular in the right superior temporal gyrus, supporting the hypothesis that a disturbed frontotemporal network is critically involved in the pathogenesis of psychopathy.

  18. Accelerator-based single-shot ultrafast transmission electron microscope with picosecond temporal resolution and nanometer spatial resolution

    Energy Technology Data Exchange (ETDEWEB)

    Xiang, D., E-mail: dxiang@sjtu.edu.cn [Key Laboratory for Laser Plasmas (Ministry of Education), Department of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240 (China); Fu, F.; Zhang, J. [Key Laboratory for Laser Plasmas (Ministry of Education), Department of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240 (China); Huang, X.; Wang, L.; Wang, X. [SLAC National Accelerator Laboratory, Menlo Park, CA 94025 (United States); Wan, W. [Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States)

    2014-09-21

    We present feasibility study of an accelerator-based ultrafast transmission electron microscope (u-TEM) capable of producing a full field image in a single-shot with simultaneous picosecond temporal resolution and nanometer spatial resolution. We study key physics related to performance of u-TEMs and discuss major challenges as well as possible solutions for practical realization of u-TEMs. The feasibility of u-TEMs is confirmed through simulations using realistic electron beam parameters. We anticipate that u-TEMs with a product of temporal and spatial resolution beyond 10{sup −19} ms will open up new opportunities in probing matter at ultrafast temporal and ultrasmall spatial scales.

  19. Spatio-Temporal Series Remote Sensing Image Prediction Based on Multi-Dictionary Bayesian Fusion

    Directory of Open Access Journals (Sweden)

    Chu He

    2017-11-01

    Full Text Available Contradictions in spatial resolution and temporal coverage emerge from earth observation remote sensing images due to limitations in technology and cost. Therefore, how to combine remote sensing images with low spatial yet high temporal resolution as well as those with high spatial yet low temporal resolution to construct images with both high spatial resolution and high temporal coverage has become an important problem called spatio-temporal fusion problem in both research and practice. A Multi-Dictionary Bayesian Spatio-Temporal Reflectance Fusion Model (MDBFM has been proposed in this paper. First, multiple dictionaries from regions of different classes are trained. Second, a Bayesian framework is constructed to solve the dictionary selection problem. A pixel-dictionary likehood function and a dictionary-dictionary prior function are constructed under the Bayesian framework. Third, remote sensing images before and after the middle moment are combined to predict images at the middle moment. Diverse shapes and textures information is learned from different landscapes in multi-dictionary learning to help dictionaries capture the distinctions between regions. The Bayesian framework makes full use of the priori information while the input image is classified. The experiments with one simulated dataset and two satellite datasets validate that the MDBFM is highly effective in both subjective and objective evaluation indexes. The results of MDBFM show more precise details and have a higher similarity with real images when dealing with both type changes and phenology changes.

  20. A use case study on late stent thrombosis for ontology-based temporal reasoning and analysis.

    Science.gov (United States)

    Clark, Kim; Sharma, Deepak; Qin, Rui; Chute, Christopher G; Tao, Cui

    2014-01-01

    In this paper, we show how we have applied the Clinical Narrative Temporal Relation Ontology (CNTRO) and its associated temporal reasoning system (the CNTRO Timeline Library) to trend temporal information within medical device adverse event report narratives. 238 narratives documenting occurrences of late stent thrombosis adverse events from the Food and Drug Administration's (FDA) Manufacturing and User Facility Device Experience (MAUDE) database were annotated and evaluated using the CNTRO Timeline Library to identify, order, and calculate the duration of temporal events. The CNTRO Timeline Library had a 95% accuracy in correctly ordering events within the 238 narratives. 41 narratives included an event in which the duration was documented, and the CNTRO Timeline Library had an 80% accuracy in correctly determining these durations. 77 narratives included documentation of a duration between events, and the CNTRO Timeline Library had a 76% accuracy in determining these durations. This paper also includes an example of how this temporal output from the CNTRO ontology can be used to verify recommendations for length of drug administration, and proposes that these same tools could be applied to other medical device adverse event narratives in order to identify currently unknown temporal trends.

  1. Spatial-Temporal Analysis on Spring Festival Travel Rush in China Based on Multisource Big Data

    Directory of Open Access Journals (Sweden)

    Jiwei Li

    2016-11-01

    Full Text Available Spring Festival travel rush is a phenomenon in China that population travel intensively surges in a short time around Chinese Spring Festival. This phenomenon, which is a special one in the urbanization process of China, brings a large traffic burden and various kinds of social problems, thereby causing widespread public concern. This study investigates the spatial-temporal characteristics of Spring Festival travel rush in 2015 through time series analysis and complex network analysis based on multisource big travel data derived from Baidu, Tencent, and Qihoo. The main results are as follows: First, big travel data of Baidu and Tencent obtained from location-based services might be more accurate and scientific than that of Qihoo. Second, two travel peaks appeared at five days before and six days after the Spring Festival, respectively, and the travel valley appeared on the Spring Festival. The Spring Festival travel network at the provincial scale did not have small-world and scale-free characteristics. Instead, the travel network showed a multicenter characteristic and a significant geographic clustering characteristic. Moreover, some travel path chains played a leading role in the network. Third, economic and social factors had more influence on the travel network than geographical location factors. The problem of Spring Festival travel rush will not be effectively improved in a short time because of the unbalanced urban-rural development and the unbalanced regional development. However, the development of the modern high-speed transport system and the modern information and communication technology can alleviate problems brought by Spring Festival travel rush. We suggest that a unified real-time traffic platform for Spring Festival travel rush should be established through the government's integration of mobile big data and the official authority data of the transportation department.

  2. Spatio-temporal representativeness of ground-based downward solar radiation measurements

    Science.gov (United States)

    Schwarz, Matthias; Wild, Martin; Folini, Doris

    2017-04-01

    Surface solar radiation (SSR) is most directly observed with ground based pyranometer measurements. Besides measurement uncertainties, which arise from the pyranometer instrument itself, also errors attributed to the limited spatial representativeness of observations from single sites for their large-scale surrounding have to be taken into account when using such measurements for energy balance studies. In this study the spatial representativeness of 157 homogeneous European downward surface solar radiation time series from the Global Energy Balance Archive (GEBA) and the Baseline Surface Radiation Network (BSRN) were examined for the period 1983-2015 by using the high resolution (0.05°) surface solar radiation data set from the Satellite Application Facility on Climate Monitoring (CM-SAF SARAH) as a proxy for the spatiotemporal variability of SSR. By correlating deseasonalized monthly SSR time series form surface observations against single collocated satellite derived SSR time series, a mean spatial correlation pattern was calculated and validated against purely observational based patterns. Generally decreasing correlations with increasing distance from station, with high correlations (R2 = 0.7) in proximity to the observational sites (±0.5°), was found. When correlating surface observations against time series from spatially averaged satellite derived SSR data (and thereby simulating coarser and coarser grids), very high correspondence between sites and the collocated pixels has been found for pixel sizes up to several degrees. Moreover, special focus was put on the quantification of errors which arise in conjunction to spatial sampling when estimating the temporal variability and trends for a larger region from a single surface observation site. For 15-year trends on a 1° grid, errors due to spatial sampling in the order of half of the measurement uncertainty for monthly mean values were found.

  3. Geosfear? - Overcoming System Boundaries by Open-source Based Monitoring of Spatio-temporal Processes

    Science.gov (United States)

    Brandt, T.; Schima, R.; Goblirsch, T.; Paschen, M.; Francyk, B.; Bumberger, J.; Zacharias, S.; Dietrich, P.; Rubin, Y.; Rinke, K.; Fleckenstein, J. H.; Schmidt, C.; Vieweg, M.

    2016-12-01

    The impact of global change, intensive agriculture and complex interactions between humans and the environment show different effects on different scales. However, the desire to obtain a better understanding of ecosystems and process dynamics in nature accentuates the need for observing these processes at higher temporal and spatial resolutions. Especially with regard to the process dynamics and heterogeneity of rivers and catchment areas, a comprehensive monitoring of the ongoing processes and effects remains to be a challenging issue. What we need are monitoring systems which can collect most diverse data across different environmental compartments and scales. Today, open-source based electronics and innovative sensors and sensor components are offering a promising approach to investigate new possibilities of mobile data acquisition to improve our understanding of the geosphere. To start with, we have designed and implemented a multi-operable, embedded Linux platform for fast integration of different sensors within a single infrastructure. In addition, a GPS module in combination with a GSM transmitter ensures the synchronization and geo-referencing of all data, no matter how old-fashioned the sensors are. To this end, initial field experiments were conducted at a 3rd order stream in the Central German Lowland. Here, we linked in-stream DOC inputs with subsurface metabolism by coupling miniaturized DOC sensor probes with a modified vertical oxygen profiler in situ. Starting from metrological observations to water quality and subsurface conditions, the overarching goal is the detection of interlinked process dynamics across highly reactive biogeochemical interfaces. Overall, the field experiments demonstrated the feasibility of this emerging technology and its potential towards a cutting-edge strategy based on a holistic and integrated process. Now, we are only a few steps away from realizing adaptive and event-triggered observations close to real

  4. Improvement of temporal signal-to-noise ratio of GRAPPA accelerated EPI using a FLASH based calibration scan

    Science.gov (United States)

    Talagala, S. L.; Sarlls, J. E.; Liu, S.; Inati, S. J.

    2015-01-01

    Purpose To demonstrate that the temporal SNR of GRAPPA accelerated EPI can be enhanced and made more spatially uniform by using a FLASH based calibration scan. Methods EPI of a phantom and human brains were acquired at 3T without and with GRAPPA acceleration factor of 2. The GRAPPA accelerated data were reconstructed using calibration scans acquired with EPI and FLASH acquisition schemes. The increase in temporal signal fluctuation due to GRAPPA reconstruction was quantified and compared. Simulated g-factor maps were also created for different calibration scans. Results GRAPPA accelerated phantom data exhibited areas with high g values when using the EPI based calibration for reconstruction. The g-factor maps were uniform when using the FLASH calibration scan. g was greater than 1.1 in 74% of pixels in 64 × 64 data reconstructed with the EPI calibration compared to only 15% when using the FLASH calibration scan. Human data also showed abnormally high g regions when using the EPI calibration but not when using the FLASH calibration scan. Use of the FLASH calibration scan increased the whole brain temporal SNR by ~12 % without affecting the image quality. Experimental observations were confirmed by simulations. Conclusion A calibration scan based on a FLASH acquisition scheme can be used to improve the temporal SNR of GRAPPA accelerated EPI time series. PMID:26192822

  5. Realigning thunder and lightning: temporal adaptation to spatiotemporally distant events.

    Directory of Open Access Journals (Sweden)

    Jordi Navarra

    Full Text Available The brain is able to realign asynchronous signals that approximately coincide in both space and time. Given that many experience-based links between visual and auditory stimuli are established in the absence of spatiotemporal proximity, we investigated whether or not temporal realignment arises in these conditions. Participants received a 3-min exposure to visual and auditory stimuli that were separated by 706 ms and appeared either from the same (Experiment 1 or from different spatial positions (Experiment 2. A simultaneity judgment task (SJ was administered right afterwards. Temporal realignment between vision and audition was observed, in both Experiment 1 and 2, when comparing the participants' SJs after this exposure phase with those obtained after a baseline exposure to audiovisual synchrony. However, this effect was present only when the visual stimuli preceded the auditory stimuli during the exposure to asynchrony. A similar pattern of results (temporal realignment after exposure to visual-leading asynchrony but not after exposure to auditory-leading asynchrony was obtained using temporal order judgments (TOJs instead of SJs (Experiment 3. Taken together, these results suggest that temporal recalibration still occurs for visual and auditory stimuli that fall clearly outside the so-called temporal window for multisensory integration and appear from different spatial positions. This temporal realignment may be modulated by long-term experience with the kind of asynchrony (vision-leading that we most frequently encounter in the outside world (e.g., while perceiving distant events.

  6. Asynchronous single-shot characterization of high-repetition-rate ultrafast waveforms using a time-lens-based temporal magnifier.

    Science.gov (United States)

    Okawachi, Yoshitomo; Salem, Reza; Johnson, Adrea R; Saha, Kasturi; Levy, Jacob S; Lipson, Michal; Gaeta, Alexander L

    2012-12-01

    We demonstrate asynchronous, single-shot characterization of an ultrafast, high-repetition-rate pulse source using a time-lens-based temporal magnifier. We measure a 225 GHz repetition-rate pulse train from a microresonator-based frequency comb. In addition, we show that such a system can be used as a frequency compressor for real-time, high-speed RF spectral characterization.

  7. Jogando com os precedentes: regras, analogias, princípios Playing with precedents: rules, analogies, principles

    Directory of Open Access Journals (Sweden)

    Antonio Moreira Maués

    2012-12-01

    Full Text Available Este artigo analisa decisões recentes do STF envolvendo a aplicação de súmulas vinculantes à luz de três concepções de precedentes, desenvolvidas por F. Schauer (precedentes como regras, C. Sunstein (precedentes como analogias e R. Dworkin (precedentes como princípios. Após a exposição dos principais aspectos de cada uma dessas teorias baseadas, respectivamente, nos conceitos de generalizações enraizadas, acordos teóricos incompletos e romance em cadeia, e discute os fundamentos que elas podem oferecer para o uso de precedentes no direito brasileiro.This article analyses the use of binding precedents by the Brazilian Supreme Court in the light of three conceptions of precedents, which are developed by F. Schauer (precedents as rules, C. Sunstein (precedents as analogies and R. Dworkin (precedents as principles. After the exposition of the main aspects of each theory, based respectively on the concepts of entrenched generalizations, incompletely theorized agreements and chain novel, the article debates the arguments that they can provide for the use of precedents in Brazilian law.

  8. Location Prediction Based on Transition Probability Matrices Constructing from Sequential Rules for Spatial-Temporal K-Anonymity Dataset.

    Directory of Open Access Journals (Sweden)

    Haitao Zhang

    Full Text Available Spatial-temporal k-anonymity has become a mainstream approach among techniques for protection of users' privacy in location-based services (LBS applications, and has been applied to several variants such as LBS snapshot queries and continuous queries. Analyzing large-scale spatial-temporal anonymity sets may benefit several LBS applications. In this paper, we propose two location prediction methods based on transition probability matrices constructing from sequential rules for spatial-temporal k-anonymity dataset. First, we define single-step sequential rules mined from sequential spatial-temporal k-anonymity datasets generated from continuous LBS queries for multiple users. We then construct transition probability matrices from mined single-step sequential rules, and normalize the transition probabilities in the transition matrices. Next, we regard a mobility model for an LBS requester as a stationary stochastic process and compute the n-step transition probability matrices by raising the normalized transition probability matrices to the power n. Furthermore, we propose two location prediction methods: rough prediction and accurate prediction. The former achieves the probabilities of arriving at target locations along simple paths those include only current locations, target locations and transition steps. By iteratively combining the probabilities for simple paths with n steps and the probabilities for detailed paths with n-1 steps, the latter method calculates transition probabilities for detailed paths with n steps from current locations to target locations. Finally, we conduct extensive experiments, and correctness and flexibility of our proposed algorithm have been verified.

  9. Location Prediction Based on Transition Probability Matrices Constructing from Sequential Rules for Spatial-Temporal K-Anonymity Dataset.

    Science.gov (United States)

    Zhang, Haitao; Chen, Zewei; Liu, Zhao; Zhu, Yunhong; Wu, Chenxue

    2016-01-01

    Spatial-temporal k-anonymity has become a mainstream approach among techniques for protection of users' privacy in location-based services (LBS) applications, and has been applied to several variants such as LBS snapshot queries and continuous queries. Analyzing large-scale spatial-temporal anonymity sets may benefit several LBS applications. In this paper, we propose two location prediction methods based on transition probability matrices constructing from sequential rules for spatial-temporal k-anonymity dataset. First, we define single-step sequential rules mined from sequential spatial-temporal k-anonymity datasets generated from continuous LBS queries for multiple users. We then construct transition probability matrices from mined single-step sequential rules, and normalize the transition probabilities in the transition matrices. Next, we regard a mobility model for an LBS requester as a stationary stochastic process and compute the n-step transition probability matrices by raising the normalized transition probability matrices to the power n. Furthermore, we propose two location prediction methods: rough prediction and accurate prediction. The former achieves the probabilities of arriving at target locations along simple paths those include only current locations, target locations and transition steps. By iteratively combining the probabilities for simple paths with n steps and the probabilities for detailed paths with n-1 steps, the latter method calculates transition probabilities for detailed paths with n steps from current locations to target locations. Finally, we conduct extensive experiments, and correctness and flexibility of our proposed algorithm have been verified.

  10. Spatio-temporal dimension of lightning flashes based on three-dimensional Lightning Mapping Array

    Science.gov (United States)

    López, Jesús A.; Pineda, Nicolau; Montanyà, Joan; Velde, Oscar van der; Fabró, Ferran; Romero, David

    2017-11-01

    3D mapping system like the LMA - Lightning Mapping Array - are a leap forward in lightning observation. LMA measurements has lead to an improvement on the analysis of the fine structure of lightning, allowing to characterize the duration and maximum extension of the cloud fraction of a lightning flash. During several years of operation, the first LMA deployed in Europe has been providing a large amount of data which now allows a statistical approach to compute the full duration and horizontal extension of the in-cloud phase of a lightning flash. The "Ebro Lightning Mapping Array" (ELMA) is used in the present study. Summer and winter lighting were analyzed for seasonal periods (Dec-Feb and Jun-Aug). A simple method based on an ellipse fitting technique (EFT) has been used to characterize the spatio-temporal dimensions from a set of about 29,000 lightning flashes including both summer and winter events. Results show an average lightning flash duration of 440 ms (450 ms in winter) and a horizontal maximum length of 15.0 km (18.4 km in winter). The uncertainties for summer lightning lengths were about ± 1.2 km and ± 0.7 km for the mean and median values respectively. In case of winter lightning, the level of uncertainty reaches up to 1 km and 0.7 km of mean and median value. The results of the successful correlation of CG discharges with the EFT method, represent 6.9% and 35.5% of the total LMA flashes detected in summer and winter respectively. Additionally, the median value of lightning lengths calculated through this correlative method was approximately 17 km for both seasons. On the other hand, the highest median ratios of lightning length to CG discharges in both summer and winter were reported for positive CG discharges.

  11. PCA based spatio-temporal decomposition and compression of 4D medical images

    Science.gov (United States)

    Lorenz, Cristian; von Berg, Jens

    2005-04-01

    The amount of per-patient image data generated by medical imaging modalities such as MRI and multi-slice CT scanners increases rapidly. This is on one hand due to an increasing spatial image resolution and on the other hand due to the expanding use of multi-phase or cine studies. A cardiac multi-phase CT scan, generated in about 20 seconds scan time, easily generates about 2GB of image data. The visualization and further processing of those data is at the edge of the abilities of current computers. We therefore present a principal component analysis (PCA) based compression algorithm, which exploits the spatial and temporal coherence of medical multi-phase image data and which allows to retrieve the images with a selectable amount of information loss. The main focus of this work is to reduce the required amount of system memory, not to reduce the required amount of disk space, i.e. at any time only the decomposed image resides in the system memory. If an intensity value for a position (x,y,z,t) is required, it is calculated on demand. This is possible, since the intensity values are expressed as fast computable weighted sums. The method has been applied to cardiac multi-phase CT datasets. It could be shown that a compression ratio of 3:1 still keeps the compression-induced losses (mainly blurring) at the noise level of the original data (about 5 Hounsfield units). Compression ratios of 5:1 and more can be achieved keeping an undisturbed visual impression of the dataset. The influence of the image compression on an automated cardiac segmentation procedure has been studied. Compression ratios up to 8:1 lead to results that only marginally deviate from results of the uncompressed image.

  12. Mapping temporal changes in connectivity using high-resolution aerial data and object based image analysis

    Science.gov (United States)

    Masselink, Rens; Anders, Niels; Keesstra, Saskia; Seeger, Manuel

    2014-05-01

    Within the field of geomorphology mapping has always been an important tool to interpret spatial and temporal distributions of phenomena and processes at the surface. In the field of connectivity however, although throughout the past decade many articles have been published, there are only very few that go into the mapping of connectivity. This study aimed at developing a new, automated method for mapping connectivity within agricultural catchments. The method, which is a combination of Object-Based Image Analysis (OBIA) and traditional geomorphological field mapping, was applied to two agricultural catchments in Navarre, Spain, both with an area of approximately 2 sq.km. An unmanned aerial vehicle (UAV) was used to take aerial photographs with a resolution of 6 cm, of which a DEM with a 12 cm resolution was created using structure-from-motion photogrammetry. Connectivity was mapped within the study areas using OBIA using a top down method, meaning that connectivity was mapped at different scale levels, starting at the largest scale. Firstly sub-catchments were automatically delineated, after which several characteristics and features that affect connectivity within the sub-catchments were classified, e.g. landuse, landslides, rills, gullies, riparian vegetation, changes in slope, ploughing direction etc. In two consecutive years (2013-2014) photographs were taken and connectivity of both catchments of both years will be compared. Future work will include a quantification of the mapped connectivity (highly connected years vs. low connected years), causes and consequences of these differences in connectivity, comparison to existing connectivity indices and comparison of mapped connectivity in sub-catchments and measured discharge.

  13. Overdiagnosis and overtreatment of thyroid cancer: A population-based temporal trend study.

    Science.gov (United States)

    Jegerlehner, Sabrina; Bulliard, Jean-Luc; Aujesky, Drahomir; Rodondi, Nicolas; Germann, Simon; Konzelmann, Isabelle; Chiolero, Arnaud

    2017-01-01

    The increase in incidence of thyroid cancer during the last decades without concomitant rise in mortality may reflect the growing detection of indolent forms of thyroid cancer, and may have fueled unnecessary thyroidectomies. Our aim was therefore, to compare recent secular trends in surgical intervention rate for thyroid cancer with the incidence and mortality of thyroid cancer to assess overdiagnosis and resulting overtreatment. We conducted a population-based temporal trend study in Switzerland from 1998 to 2012. All cases of invasive thyroid cancer, deaths from thyroid cancer, and cancer-related thyroidectomies were analyzed. We calculated changes in age-standardized thyroid cancer incidence rates, stratified by histologic subtype and tumor stage, thyroid cancer-specific mortality, and thyroidectomy rates. Between 1998 and 2012, the age-standardized annual incidence of thyroid cancer increased from 5.9 to 11.7 cases/100,000 among women (annual mean absolute increase: +0.43/100,000/year) and from 2.7 to 3.9 cases/100,000 among men (+0.11/100,000/year). The increase was limited to the papillary subtype, the most indolent form of thyroid cancer. The incidence of early stages increased sharply, the incidence of advanced stages increased marginally, and the mortality from thyroid cancer decreased slightly. There was a three- to four-fold increase in the age-standardized annual thyroidectomy rate in both sexes. We observed a large increase in the incidence of thyroid cancer, limited to papillary and early stage tumors, with a three- to four-fold parallel increase in thyroidectomy. The mortality slightly decreased. These findings suggest that a substantial and growing part of the detected thyroid cancers are overdiagnosed and overtreated. Targeted screening and diagnostic strategies are warranted to avoid overdetection and unnecessary treatment of thyroid cancers.

  14. Evaluation of a haptics-based virtual reality temporal bone simulator for anatomy and surgery training.

    Science.gov (United States)

    Fang, Te-Yung; Wang, Pa-Chun; Liu, Chih-Hsien; Su, Mu-Chun; Yeh, Shih-Ching

    2014-02-01

    Virtual reality simulation training may improve knowledge of anatomy and surgical skills. We evaluated a 3-dimensional, haptic, virtual reality temporal bone simulator for dissection training. The subjects were 7 otolaryngology residents (3 training sessions each) and 7 medical students (1 training session each). The virtual reality temporal bone simulation station included a computer with software that was linked to a force-feedback hand stylus, and the system recorded performance and collisions with vital anatomic structures. Subjects performed virtual reality dissections and completed questionnaires after the training sessions. Residents and students had favorable responses to most questions of the technology acceptance model (TAM) questionnaire. The average TAM scores were above neutral for residents and medical students in all domains, and the average TAM score for residents was significantly higher for the usefulness domain and lower for the playful domain than students. The average satisfaction questionnaire for residents showed that residents had greater overall satisfaction with cadaver temporal bone dissection training than training with the virtual reality simulator or plastic temporal bone. For medical students, the average comprehension score was significantly increased from before to after training for all anatomic structures. Medical students had significantly more collisions with the dura than residents. The residents had similar mean performance scores after the first and third training sessions for all dissection procedures. The virtual reality temporal bone simulator provided satisfactory training for otolaryngology residents and medical students. Copyright © 2013. Published by Elsevier Ireland Ltd.

  15. Kronecker PCA based spatio-temporal modeling of video for dismount classification

    Science.gov (United States)

    Greenewald, Kristjan H.; Hero, Alfred O.

    2014-06-01

    We consider the application of KronPCA spatio-temporal modeling techniques1, 2 to the extraction of spatiotemporal features for video dismount classification. KronPCA performs a low-rank type of dimensionality reduction that is adapted to spatio-temporal data and is characterized by the T frame multiframe mean μ and covariance ∑ of p spatial features. For further regularization and improved inverse estimation, we also use the diagonally corrected KronPCA shrinkage methods we presented in.1 We apply this very general method to the modeling of the multivariate temporal behavior of HOG features extracted from pedestrian bounding boxes in video, with gender classification in a challenging dataset chosen as a specific application. The learned covariances for each class are used to extract spatiotemporal features which are then classified, achieving competitive classification performance.

  16. Association of cognition with temporal discounting in community based older persons

    Directory of Open Access Journals (Sweden)

    Boyle Patricia A

    2012-08-01

    Full Text Available Abstract Background The objective of this study was to test the hypothesis that cognitive function is negatively associated with temporal discounting in old age. Methods Participants were 388 community-dwelling older persons without dementia from the Rush Memory and Aging Project, an ongoing longitudinal epidemiologic study of aging in the Chicago metropolitan area. Temporal discounting was measured using standard questions in which participants were asked to choose between an immediate, smaller payment and a delayed, larger one. Cognition was measured using a detailed battery including 19 tests. The association between cognition and temporal discounting was examined via mixed models adjusted for age, sex, education, income, and the number of chronic medical conditions. Results Descriptive data revealed a consistent pattern whereby older persons with lower cognitive function were more likely to discount greater but delayed rewards compared to those with higher cognitive function. Further, in a mixed effect model adjusted for age, sex, education, income, and chronic medical conditions, global cognitive function was negatively associated with temporal discounting (estimate = −0.45, SE = 0.18, p = 0.015, such that a person with lower cognition exhibited greater discounting. Finally, in subsequent models examining domain specific associations, perceptual speed and visuospatial abilities were associated with temporal discounting, but episodic memory, semantic memory and working memory were not. Conclusion Among older persons without dementia, a lower level of cognitive function is associated with greater temporal discounting. These findings have implications regarding the ability of older persons to make decisions that involve delayed rewards but maximize well-being.

  17. Widespread EEG changes precede focal seizures.

    Directory of Open Access Journals (Sweden)

    Piero Perucca

    Full Text Available The process by which the brain transitions into an epileptic seizure is unknown. In this study, we investigated whether the transition to seizure is associated with changes in brain dynamics detectable in the wideband EEG, and whether differences exist across underlying pathologies. Depth electrode ictal EEG recordings from 40 consecutive patients with pharmacoresistant lesional focal epilepsy were low-pass filtered at 500 Hz and sampled at 2,000 Hz. Predefined EEG sections were selected immediately before (immediate preictal, and 30 seconds before the earliest EEG sign suggestive of seizure activity (baseline. Spectral analysis, visual inspection and discrete wavelet transform were used to detect standard (delta, theta, alpha, beta and gamma and high-frequency bands (ripples and fast ripples. At the group level, each EEG frequency band activity increased significantly from baseline to the immediate preictal section, mostly in a progressive manner and independently of any modification in the state of vigilance. Preictal increases in each frequency band activity were widespread, being observed in the seizure-onset zone and lesional tissue, as well as in remote regions. These changes occurred in all the investigated pathologies (mesial temporal atrophy/sclerosis, local/regional cortical atrophy, and malformations of cortical development, but were more pronounced in mesial temporal atrophy/sclerosis. Our findings indicate that a brain state change with distinctive features, in the form of unidirectional changes across the entire EEG bandwidth, occurs immediately prior to seizure onset. We postulate that these changes might reflect a facilitating state of the brain which enables a susceptible region to generate seizures.

  18. Widespread EEG Changes Precede Focal Seizures

    Science.gov (United States)

    Perucca, Piero; Dubeau, François; Gotman, Jean

    2013-01-01

    The process by which the brain transitions into an epileptic seizure is unknown. In this study, we investigated whether the transition to seizure is associated with changes in brain dynamics detectable in the wideband EEG, and whether differences exist across underlying pathologies. Depth electrode ictal EEG recordings from 40 consecutive patients with pharmacoresistant lesional focal epilepsy were low-pass filtered at 500 Hz and sampled at 2,000 Hz. Predefined EEG sections were selected immediately before (immediate preictal), and 30 seconds before the earliest EEG sign suggestive of seizure activity (baseline). Spectral analysis, visual inspection and discrete wavelet transform were used to detect standard (delta, theta, alpha, beta and gamma) and high-frequency bands (ripples and fast ripples). At the group level, each EEG frequency band activity increased significantly from baseline to the immediate preictal section, mostly in a progressive manner and independently of any modification in the state of vigilance. Preictal increases in each frequency band activity were widespread, being observed in the seizure-onset zone and lesional tissue, as well as in remote regions. These changes occurred in all the investigated pathologies (mesial temporal atrophy/sclerosis, local/regional cortical atrophy, and malformations of cortical development), but were more pronounced in mesial temporal atrophy/sclerosis. Our findings indicate that a brain state change with distinctive features, in the form of unidirectional changes across the entire EEG bandwidth, occurs immediately prior to seizure onset. We postulate that these changes might reflect a facilitating state of the brain which enables a susceptible region to generate seizures. PMID:24260523

  19. Temporal Lobe Toxicity Analysis After Proton Radiation Therapy for Skull Base Tumors

    Energy Technology Data Exchange (ETDEWEB)

    Pehlivan, Berrin [Center for Proton Therapy, Paul Scherrer Institute, Villigen (Switzerland); Ares, Carmen, E-mail: carmen.ares@psi.ch [Center for Proton Therapy, Paul Scherrer Institute, Villigen (Switzerland); Lomax, Antony J.; Stadelmann, Otto; Goitein, Gudrun; Timmermann, Beate; Schneider, Ralf A.; Hug, Eugen B. [Center for Proton Therapy, Paul Scherrer Institute, Villigen (Switzerland)

    2012-08-01

    Purpose: Temporal lobe (TL) parenchyma toxicity constitutes one of the most frequent late adverse event in high-dose proton therapy (PT) for tumors of the skull base. We analyzed clinical events with dosimetric parameters in our patients treated for skull base tumors with spot-scanning PT. Methods and Materials: Between 1998 and 2005, a total of 62 patients received PT to a median dose of 71.7 Gy (relative biologic effectiveness [RBE]) (range, 63-74 Gy). The dose-volume histogram of each TL and the entire brain parenchyma (BP) were analyzed according to maximum, mean, and minimum dose as well as doses to 0.5, 1, 2, and 3 cc of brain volume (D{sub 0.5}, D{sub 1}, D{sub 2}, D{sub 3}) and correlated with clinical events. Generalized equivalent uniform dose (gEUD) values were calculated. Results: At a mean follow-up of 38 months (range, 14-92 months), 2 patients had developed symptomatic Grade 3 and 5 patients asymptomatic Grade 1 TL toxicity. Mean doses to a 2-cc volume of BP increased from 71 {+-} 5 Gy (RBE) for no toxicity to 74 {+-} 5 Gy (RBE) for Grade 1 and to 76 {+-} 2 Gy (RBE) for Grade 3 toxicity. TL events occurred in 6 of 7 patients (86%) at or above dose levels of {>=}64 Gy (RBE) D{sub 3}, {>=}68 Gy (RBE) D{sub 2}, {>=}72 Gy (RBE) D{sub 1}, and {>=}73 Gy (RBE) D{sub 0.5}, respectively (p = NS). No statistically significant dose/volume threshold was detected between patients experiencing no toxicity vs. Grade 1 or Grade 3. A strong trend for Grade 1 and 3 events was observed, when the gEUD was 60 Gy. Conclusions: A statistically significant normal tissue threshold dose for BP has not been successfully defined. However, our data suggest that tolerance of TL and BP to fractionated radiotherapy appears to be correlated with tissue volume included in high-dose regions. Additional follow-up time and patient accrual is likely needed to achieve clinical significance for these dose-volume parameters investigated. Our findings support the importance of establishing

  20. Temporal and spatial variation in recent vehicular emission inventories in China based on dynamic emission factors.

    Science.gov (United States)

    Cai, Hao; Xie, Shaodong

    2013-03-01

    emissions. This paper tracks the temporal and spatial variation characteristics in recent vehicular emission inventories in China based on dynamic emission factors. The fact that CO and NMVOC emissions kept growing at reduced rates and the NOx, PM10, and GHG emissions continued rising rapidly reveals that it was insufficient to bring down the rapid growth of NOx, PM10, and CO2 emissions by merely tightening emission standards and improving fuel quality of motor vehicles. The results will assist decision makers to formulate effective control policies for China's vehicular emissions. The improved methodologies are applicable for routine update of China's vehicular emission inventories.

  1. Progression of disease preceding lower extremity amputation in Denmark

    DEFF Research Database (Denmark)

    Jensen, Pia Søe; Petersen, Janne; Kirketerp-Møller, Klaus

    2017-01-01

    OBJECTIVES: Patients with non-traumatic lower extremity amputation are characterised by high age, multi-morbidity and polypharmacy and long-term complications of atherosclerosis and diabetes. To ensure early identification of patients at risk of amputation, we need to gain knowledge about...... the progression of diseases related to lower extremity amputations during the years preceding the amputation. DESIGN: A retrospective population-based national registry study. SETTING: The study includes data on demographics, diagnoses, surgery, medications and healthcare services from five national registries....... Data were retrieved from 14 years before until 1 year after the amputation. Descriptive statistics were used to describe the progression of diseases and use of medication and healthcare services. PARTICIPANTS: An unselected cohort of patients (≥50 years; n=2883) subjected to a primary non...

  2. Fitting model-based psychometric functions to simultaneity and temporal-order judgment data: MATLAB and R routines.

    Science.gov (United States)

    Alcalá-Quintana, Rocío; García-Pérez, Miguel A

    2013-12-01

    Research on temporal-order perception uses temporal-order judgment (TOJ) tasks or synchrony judgment (SJ) tasks in their binary SJ2 or ternary SJ3 variants. In all cases, two stimuli are presented with some temporal delay, and observers judge the order of presentation. Arbitrary psychometric functions are typically fitted to obtain performance measures such as sensitivity or the point of subjective simultaneity, but the parameters of these functions are uninterpretable. We describe routines in MATLAB and R that fit model-based functions whose parameters are interpretable in terms of the processes underlying temporal-order and simultaneity judgments and responses. These functions arise from an independent-channels model assuming arrival latencies with exponential distributions and a trichotomous decision space. Different routines fit data separately for SJ2, SJ3, and TOJ tasks, jointly for any two tasks, or also jointly for the three tasks (for common cases in which two or even the three tasks were used with the same stimuli and participants). Additional routines provide bootstrap p-values and confidence intervals for estimated parameters. A further routine is included that obtains performance measures from the fitted functions. An R package for Windows and source code of the MATLAB and R routines are available as Supplementary Files.

  3. User requirements for geo-collaborative work with spatio-temporal data in a web-based virtual globe environment.

    Science.gov (United States)

    Yovcheva, Zornitza; van Elzakker, Corné P J M; Köbben, Barend

    2013-11-01

    Web-based tools developed in the last couple of years offer unique opportunities to effectively support scientists in their effort to collaborate. Communication among environmental researchers often involves not only work with geographical (spatial), but also with temporal data and information. Literature still provides limited documentation when it comes to user requirements for effective geo-collaborative work with spatio-temporal data. To start filling this gap, our study adopted a User-Centered Design approach and first explored the user requirements of environmental researchers working on distributed research projects for collaborative dissemination, exchange and work with spatio-temporal data. Our results show that system design will be mainly influenced by the nature and type of data users work with. From the end-users' perspective, optimal conversion of huge files of spatio-temporal data for further dissemination, accuracy of conversion, organization of content and security have a key role for effective geo-collaboration. Copyright © 2012 Elsevier Ltd and The Ergonomics Society. All rights reserved.

  4. Inference of selection based on temporal genetic differentiation in the study of highly polymorphic multigene families.

    Directory of Open Access Journals (Sweden)

    Mark McMullan

    Full Text Available The co-evolutionary arms race between host immune genes and parasite virulence genes is known as Red Queen dynamics. Temporal fluctuations in allele frequencies, or the 'turnover' of alleles at immune genes, are concordant with predictions of the Red Queen hypothesis. Such observations are often taken as evidence of host-parasite co-evolution. Here, we use computer simulations of the Major Histocompatibility Complex (MHC of guppies (Poecilia reticulata to study the turnover rate of alleles (temporal genetic differentiation, G'(ST. Temporal fluctuations in MHC allele frequencies can be ≥≤order of magnitude larger than changes observed at neutral loci. Although such large fluctuations in the MHC are consistent with Red Queen dynamics, simulations show that other demographic and population genetic processes can account for this observation, these include: (1 overdominant selection, (2 fluctuating population size within a metapopulation, and (3 the number of novel MHC alleles introduced by immigrants when there are multiple duplicated genes. Synergy between these forces combined with migration rate and the effective population size can drive the rapid turnover in MHC alleles. We posit that rapid allelic turnover is an inherent property of highly polymorphic multigene families and that it cannot be taken as evidence of Red Queen dynamics. Furthermore, combining temporal samples in spatial F(ST outlier analysis may obscure the signal of selection.

  5. Tissue mimicking simulations for temporal enhanced ultrasound-based tissue typing

    Science.gov (United States)

    Bayat, Sharareh; Imani, Farhad; Gerardo, Carlos D.; Nir, Guy; Azizi, Shekoofeh; Yan, Pingkun; Tahmasebi, Amir; Wilson, Storey; Iczkowski, Kenneth A.; Lucia, M. Scott; Goldenberg, Larry; Salcudean, Septimiu E.; Mousavi, Parvin; Abolmaesumi, Purang

    2017-03-01

    Temporal enhanced ultrasound (TeUS) is an imaging approach where a sequence of temporal ultrasound data is acquired and analyzed for tissue typing. Previously, in a series of in vivo and ex vivo studies we have demonstrated that, this approach is effective for detecting prostate and breast cancers. Evidences derived from our experiments suggest that both ultrasound-signal related factors such as induced heat and tissue-related factors such as the distribution and micro-vibration of scatterers lead to tissue typing information in TeUS. In this work, we simulate mechanical micro-vibrations of scatterers in tissue-mimicking phantoms that have various scatterer densities reflecting benign and cancerous tissue structures. Finite element modeling (FEM) is used for this purpose where the vertexes are scatterers representing cell nuclei. The initial positions of scatterers are determined by the distribution of nuclei segmented from actual digital histology scans of prostate cancer patients. Subsequently, we generate ultrasound images of the simulated tissue structure using the Field II package resulting in a temporal enhanced ultrasound. We demonstrate that the micro-vibrations of scatterers are captured by temporal ultrasound data and this information can be exploited for tissue typing.

  6. Time-based forgetting in visual working memory reflects temporal distinctiveness, not decay.

    Science.gov (United States)

    Souza, Alessandra S; Oberauer, Klaus

    2015-02-01

    Is forgetting from working memory (WM) better explained by decay or interference? The answer to this question is the topic of an ongoing debate. Recently, a number of studies showed that performance in tests of visual WM declines with an increasing unfilled retention interval. This finding was interpreted as revealing decay. Alternatively, it can be explained by interference theories as an effect of temporal distinctiveness. According to decay theories, forgetting depends on the absolute time elapsed since the event to be retrieved. In contrast, temporal distinctiveness theories predict that memory depends on relative time, that is, the time since the to-be-retrieved event relative to the time since other, potentially interfering events. In the present study, we contrasted the effects of absolute time and relative time on forgetting from visual WM, using a continuous color recall task. To this end, we varied the retention interval and the inter-trial interval. The error in reporting the target color was a function of the ratio of the retention interval to the inter-trial interval, as predicted by temporal distinctiveness theories. Mixture modeling revealed that lower temporal distinctiveness produced a lower probability of reporting the target, but no changes in its precision in memory. These data challenge the role of decay in accounting for performance in tests of visual WM, and show that the relative spacing of events in time determines the degree of interference.

  7. A Kinect based sign language recognition system using spatio-temporal features

    Science.gov (United States)

    Memiş, Abbas; Albayrak, Songül

    2013-12-01

    This paper presents a sign language recognition system that uses spatio-temporal features on RGB video images and depth maps for dynamic gestures of Turkish Sign Language. Proposed system uses motion differences and accumulation approach for temporal gesture analysis. Motion accumulation method, which is an effective method for temporal domain analysis of gestures, produces an accumulated motion image by combining differences of successive video frames. Then, 2D Discrete Cosine Transform (DCT) is applied to accumulated motion images and temporal domain features transformed into spatial domain. These processes are performed on both RGB images and depth maps separately. DCT coefficients that represent sign gestures are picked up via zigzag scanning and feature vectors are generated. In order to recognize sign gestures, K-Nearest Neighbor classifier with Manhattan distance is performed. Performance of the proposed sign language recognition system is evaluated on a sign database that contains 1002 isolated dynamic signs belongs to 111 words of Turkish Sign Language (TSL) in three different categories. Proposed sign language recognition system has promising success rates.

  8. Model-based analysis of spatio-temporal changes in land use in Northeast China

    NARCIS (Netherlands)

    Xia, T.; Wu, W.; Zhou, Q.; Verburg, P.H.; Yu, Q.Y.; Yang, P.; Ye, L.

    2016-01-01

    Spatially explicit modeling techniques recently emerged as an alternative to monitor land use changes. This study adopted the well-known CLUE-S (Conversion of Land Use and its Effects at Small regional extent) model to analyze the spatio-temporal land use changes in a hot-spot in Northeast China

  9. Optimal Bidding and Operation of a Power Plant with Solvent-Based Carbon Capture under a CO2 Allowance Market: A Solution with a Reinforcement Learning-Based Sarsa Temporal-Difference Algorithm

    Directory of Open Access Journals (Sweden)

    Ziang Li

    2017-04-01

    Full Text Available In this paper, a reinforcement learning (RL-based Sarsa temporal-difference (TD algorithm is applied to search for a unified bidding and operation strategy for a coal-fired power plant with monoethanolamine (MEA-based post-combustion carbon capture under different carbon dioxide (CO2 allowance market conditions. The objective of the decision maker for the power plant is to maximize the discounted cumulative profit during the power plant lifetime. Two constraints are considered for the objective formulation. Firstly, the tradeoff between the energy-intensive carbon capture and the electricity generation should be made under presumed fixed fuel consumption. Secondly, the CO2 allowances purchased from the CO2 allowance market should be approximately equal to the quantity of CO2 emission from power generation. Three case studies are demonstrated thereafter. In the first case, we show the convergence of the Sarsa TD algorithm and find a deterministic optimal bidding and operation strategy. In the second case, compared with the independently designed operation and bidding strategies discussed in most of the relevant literature, the Sarsa TD-based unified bidding and operation strategy with time-varying flexible market-oriented CO2 capture levels is demonstrated to help the power plant decision maker gain a higher discounted cumulative profit. In the third case, a competitor operating another power plant identical to the preceding plant is considered under the same CO2 allowance market. The competitor also has carbon capture facilities but applies a different strategy to earn profits. The discounted cumulative profits of the two power plants are then compared, thus exhibiting the competitiveness of the power plant that is using the unified bidding and operation strategy explored by the Sarsa TD algorithm.

  10. Temporal Moments revisited: Why there is there no better way for physically-based model reduction in time

    Science.gov (United States)

    Leube, P.; Nowak, W.; Schneider, G.

    2011-12-01

    Many hydrogeological problems are highly complex in space and time, coupled with scale issues, variability and uncertainty. Especially time-dependent models often consume enormous computational resources. Model reduction techniques make stochastic modeling, probabilistic risk assessment and inverse problems more accessible to large-scale realistic applications. Temporal Moments (TM) are a promising approach to reduce the time demands and complexity of transient hydrogeological simulations. They reduce transient governing equations to steady-state and directly simulate the temporal characteristics of the system, if the equations are linear and coefficients are time-independent. This is achieved by an integral transform, projecting the dynamic system response onto monomials in time. In comparison to classical approaches of model reduction that involve orthogonal base functions, however, the monomials used for TM are non-orthogonal base functions, and this might impair the quality and efficiency of model reduction. Thus, we raise the question if there are more suitable temporal base-functions than the monomials that lead to TM. In this work, we will derive theoretically that there is only a limited class of temporal base functions that can reduce hydrogeological models. By comparing those to TM we conclude that, in terms of gained efficiency versus maintained accuracy, TM are the best possible choice. While our theoretical results hold for all systems of linear PDEs with any order of time derivations, we illustrate our study with an example on pumping tests in a confined aquifer. For that, we demonstrate that using two or three TM is sufficient to represent more than 90 % of the dynamic behavior.

  11. Page JUDICIAL PRECEDENT IN THE NIGERIAN LEGAL SYSTEM

    African Journals Online (AJOL)

    Fr. Ikenga

    Abstract. Judicial precedent is an age-long feature of municipal judicial systems of the common law including. Nigeria. The review of the practice in Nigeria reveals that its serves the cause of justice and makes predictability of the outcome of legal suits possible. Three models of judicial precedent have been identified and ...

  12. Image Fusion-Based Land Cover Change Detection Using Multi-Temporal High-Resolution Satellite Images

    Directory of Open Access Journals (Sweden)

    Biao Wang

    2017-08-01

    Full Text Available Change detection is usually treated as a problem of explicitly detecting land cover transitions in satellite images obtained at different times, and helps with emergency response and government management. This study presents an unsupervised change detection method based on the image fusion of multi-temporal images. The main objective of this study is to improve the accuracy of unsupervised change detection from high-resolution multi-temporal images. Our method effectively reduces change detection errors, since spatial displacement and spectral differences between multi-temporal images are evaluated. To this end, a total of four cross-fused images are generated with multi-temporal images, and the iteratively reweighted multivariate alteration detection (IR-MAD method—a measure for the spectral distortion of change information—is applied to the fused images. In this experiment, the land cover change maps were extracted using multi-temporal IKONOS-2, WorldView-3, and GF-1 satellite images. The effectiveness of the proposed method compared with other unsupervised change detection methods is demonstrated through experimentation. The proposed method achieved an overall accuracy of 80.51% and 97.87% for cases 1 and 2, respectively. Moreover, the proposed method performed better when differentiating the water area from the vegetation area compared to the existing change detection methods. Although the water area beneath moderate and sparse vegetation canopy was captured, vegetation cover and paved regions of the water body were the main sources of omission error, and commission errors occurred primarily in pixels of mixed land use and along the water body edge. Nevertheless, the proposed method, in conjunction with high-resolution satellite imagery, offers a robust and flexible approach to land cover change mapping that requires no ancillary data for rapid implementation.

  13. Temporal changes of diffusion patterns in mild traumatic brain injury via group-based semi-blind source separation.

    Science.gov (United States)

    Jing, Min; McGinnity, T Martin; Coleman, Sonya; Fuchs, Armin; Kelso, J A Scott

    2015-07-01

    Despite the emerging applications of diffusion tensor imaging (DTI) to mild traumatic brain injury (mTBI), very few investigations have been reported related to temporal changes in quantitative diffusion patterns, which may help to assess recovery from head injury and the long term impact associated with cognitive and behavioral impairments caused by mTBI. Most existing methods are focused on detection of mTBI affected regions rather than quantification of temporal changes following head injury. Furthermore, most methods rely on large data samples as required for statistical analysis and, thus, are less suitable for individual case studies. In this paper, we introduce an approach based on spatial group independent component analysis (GICA), in which the diffusion scalar maps from an individual mTBI subject and the average of a group of controls are arranged according to their data collection time points. In addition, we propose a constrained GICA (CGICA) model by introducing the prior information into the GICA decomposition process, thus taking available knowledge of mTBI into account. The proposed method is evaluated based on DTI data collected from American football players including eight controls and three mTBI subjects (at three time points post injury). The results show that common spatial patterns within the diffusion maps were extracted as spatially independent components (ICs) by GICA. The temporal change of diffusion patterns during recovery is revealed by the time course of the selected IC. The results also demonstrate that the temporal change can be further influenced by incorporating the prior knowledge of mTBI (if available) based on the proposed CGICA model. Although a small sample of mTBI subjects is studied, as a proof of concept, the preliminary results provide promising insight for applications of DTI to study recovery from mTBI and may have potential for individual case studies in practice.

  14. On a concept of computer game implementation based on a temporal logic

    Science.gov (United States)

    Szymańska, Emilia; Adamek, Marek J.; Mulawka, Jan J.

    2017-08-01

    Time is a concept which underlies all the contemporary civilization. Therefore, it was necessary to create mathematical tools that allow a precise way to describe the complex time dependencies. One such tool is temporal logic. Its definition, description and characteristics will be presented in this publication. Then the authors will conduct a discussion on the usefulness of this tool in context of creating storyline in computer games such as RPG genre.

  15. A Learning Based Approach to Control Synthesis of Markov Decision Processes for Linear Temporal Logic Specifications

    Science.gov (United States)

    2014-09-20

    of the automata -theoretic approach,” in Formal Methods for Real-Time and Probabilistic Systems, ser. Lecture Notes in Computer Science, 1999, vol...1601, pp. 265–276. [11] J. Klein and C. Baier, “Experiments with deterministic ω- automata for formulas of linear temporal logic,” in Implementation and...Application of Automata . Springer, 2004. [12] S. Safra, “On the complexity of ω- automata ,” in Proceedings of the 29th Annual Symposium on Foundations

  16. Independent Component Analysis (ICA) based-clustering of temporal RNA-seq data.

    Science.gov (United States)

    Nascimento, Moysés; Silva, Fabyano Fonseca E; Sáfadi, Thelma; Nascimento, Ana Carolina Campana; Ferreira, Talles Eduardo Maciel; Barroso, Laís Mayara Azevedo; Ferreira Azevedo, Camila; Guimarães, Simone Eliza Faccione; Serão, Nick Vergara Lopes

    2017-01-01

    Gene expression time series (GETS) analysis aims to characterize sets of genes according to their longitudinal patterns of expression. Due to the large number of genes evaluated in GETS analysis, an useful strategy to summarize biological functional processes and regulatory mechanisms is through clustering of genes that present similar expression pattern over time. Traditional cluster methods usually ignore the challenges in GETS, such as the lack of data normality and small number of temporal observations. Independent Component Analysis (ICA) is a statistical procedure that uses a transformation to convert raw time series data into sets of values of independent variables, which can be used for cluster analysis to identify sets of genes with similar temporal expression patterns. ICA allows clustering small series of distribution-free data while accounting for the dependence between subsequent time-points. Using temporal simulated and real (four libraries of two pig breeds at 21, 40, 70 and 90 days of gestation) RNA-seq data set we present a methodology (ICAclust) that jointly considers independent components analysis (ICA) and a hierarchical method for clustering GETS. We compare ICAclust results with those obtained for K-means clustering. ICAclust presented, on average, an absolute gain of 5.15% over the best K-means scenario. Considering the worst scenario for K-means, the gain was of 84.85%, when compared with the best ICAclust result. For the real data set, genes were grouped into six distinct clusters with 89, 51, 153, 67, 40, and 58 genes each, respectively. In general, it can be observed that the 6 clusters presented very distinct expression patterns. Overall, the proposed two-step clustering method (ICAclust) performed well compared to K-means, a traditional method used for cluster analysis of temporal gene expression data. In ICAclust, genes with similar expression pattern over time were clustered together.

  17. Pathology-Based Approach to Seizure Outcome After Surgery for Pharmacoresistant Medial Temporal Lobe Epilepsy.

    Science.gov (United States)

    Martinoni, Matteo; Berti, Pier Paolo; Marucci, Gianluca; Rubboli, Guido; Volpi, Lilia; Riguzzi, Patrizia; Marliani, Federica; Toni, Francesco; Bisulli, Francesca; Tinuper, Paolo; Michelucci, Roberto; Baruzzi, Agostino; Giulioni, Marco

    2016-06-01

    Hippocampal sclerosis (HS) is the most common cause of drug-resistant medial temporal lobe epilepsy (MTLE). Structural abnormalities such as HS, granule cell pathology (GCP), and focal cortical dysplasia (FCD) have been classified histopathologically, possibly allowing a more accurate assessment of prognostic seizure and neuropsychologic outcomes. We correlated seizure outcome with comprehensive temporal lobe pathologic findings, identified according to the most recent classification systems of HS, GCP, and FCD. All the 83 patients who underwent anterior temporal lobectomy (ATL) for drug-resistant MTLE and with a proven diagnosis of HS between April 2001 and May 2014 were collected. Patients were divided in 2 main groups: 1) isolated HS with/without GCP (HS +/- GCP); and 2) HS associated with FCD with/without GCP (HS+FCD +/- GCP). Patients were followed up at least 1 year, and seizure outcome was reported in accordance with Engel classification. Group I: HS +/- GCP: Statistical analysis confirmed a better outcome in HS + GCP patients than in HS-no GCP (P epilepsy surgery might improve the interpretation of the results, could predict which cases will enjoy a better seizure outcome, and could help to the comprehension of the causes of failures. Copyright © 2016 Elsevier Inc. All rights reserved.

  18. A population-based temporal logic gate for timing and recording chemical events.

    Science.gov (United States)

    Hsiao, Victoria; Hori, Yutaka; Rothemund, Paul Wk; Murray, Richard M

    2016-05-17

    Engineered bacterial sensors have potential applications in human health monitoring, environmental chemical detection, and materials biosynthesis. While such bacterial devices have long been engineered to differentiate between combinations of inputs, their potential to process signal timing and duration has been overlooked. In this work, we present a two-input temporal logic gate that can sense and record the order of the inputs, the timing between inputs, and the duration of input pulses. Our temporal logic gate design relies on unidirectional DNA recombination mediated by bacteriophage integrases to detect and encode sequences of input events. For an E. coli strain engineered to contain our temporal logic gate, we compare predictions of Markov model simulations with laboratory measurements of final population distributions for both step and pulse inputs. Although single cells were engineered to have digital outputs, stochastic noise created heterogeneous single-cell responses that translated into analog population responses. Furthermore, when single-cell genetic states were aggregated into population-level distributions, these distributions contained unique information not encoded in individual cells. Thus, final differentiated sub-populations could be used to deduce order, timing, and duration of transient chemical events. © 2016 The Authors. Published under the terms of the CC BY 4.0 license.

  19. Correlated Spatio-Temporal Data Collection in Wireless Sensor Networks Based on Low Rank Matrix Approximation and Optimized Node Sampling

    Directory of Open Access Journals (Sweden)

    Xinglin Piao

    2014-12-01

    Full Text Available The emerging low rank matrix approximation (LRMA method provides an energy efficient scheme for data collection in wireless sensor networks (WSNs by randomly sampling a subset of sensor nodes for data sensing. However, the existing LRMA based methods generally underutilize the spatial or temporal correlation of the sensing data, resulting in uneven energy consumption and thus shortening the network lifetime. In this paper, we propose a correlated spatio-temporal data collection method for WSNs based on LRMA. In the proposed method, both the temporal consistence and the spatial correlation of the sensing data are simultaneously integrated under a new LRMA model. Moreover, the network energy consumption issue is considered in the node sampling procedure. We use Gini index to measure both the spatial distribution of the selected nodes and the evenness of the network energy status, then formulate and resolve an optimization problem to achieve optimized node sampling. The proposed method is evaluated on both the simulated and real wireless networks and compared with state-of-the-art methods. The experimental results show the proposed method efficiently reduces the energy consumption of network and prolongs the network lifetime with high data recovery accuracy and good stability.

  20. a Comparison Study of Different Kernel Functions for Svm-Based Classification of Multi-Temporal Polarimetry SAR Data

    Science.gov (United States)

    Yekkehkhany, B.; Safari, A.; Homayouni, S.; Hasanlou, M.

    2014-10-01

    In this paper, a framework is developed based on Support Vector Machines (SVM) for crop classification using polarimetric features extracted from multi-temporal Synthetic Aperture Radar (SAR) imageries. The multi-temporal integration of data not only improves the overall retrieval accuracy but also provides more reliable estimates with respect to single-date data. Several kernel functions are employed and compared in this study for mapping the input space to higher Hilbert dimension space. These kernel functions include linear, polynomials and Radial Based Function (RBF). The method is applied to several UAVSAR L-band SAR images acquired over an agricultural area near Winnipeg, Manitoba, Canada. In this research, the temporal alpha features of H/A/α decomposition method are used in classification. The experimental tests show an SVM classifier with RBF kernel for three dates of data increases the Overall Accuracy (OA) to up to 3% in comparison to using linear kernel function, and up to 1% in comparison to a 3rd degree polynomial kernel function.

  1. Fundamental statistical relationships between monthly and daily meteorological variables: Temporal downscaling of weather based on a global observational dataset

    Science.gov (United States)

    Sommer, Philipp; Kaplan, Jed

    2016-04-01

    Accurate modelling of large-scale vegetation dynamics, hydrology, and other environmental processes requires meteorological forcing on daily timescales. While meteorological data with high temporal resolution is becoming increasingly available, simulations for the future or distant past are limited by lack of data and poor performance of climate models, e.g., in simulating daily precipitation. To overcome these limitations, we may temporally downscale monthly summary data to a daily time step using a weather generator. Parameterization of such statistical models has traditionally been based on a limited number of observations. Recent developments in the archiving, distribution, and analysis of "big data" datasets provide new opportunities for the parameterization of a temporal downscaling model that is applicable over a wide range of climates. Here we parameterize a WGEN-type weather generator using more than 50 million individual daily meteorological observations, from over 10'000 stations covering all continents, based on the Global Historical Climatology Network (GHCN) and Synoptic Cloud Reports (EECRA) databases. Using the resulting "universal" parameterization and driven by monthly summaries, we downscale mean temperature (minimum and maximum), cloud cover, and total precipitation, to daily estimates. We apply a hybrid gamma-generalized Pareto distribution to calculate daily precipitation amounts, which overcomes much of the inability of earlier weather generators to simulate high amounts of daily precipitation. Our globally parameterized weather generator has numerous applications, including vegetation and crop modelling for paleoenvironmental studies.

  2. Temporal-spatial reach parameters derived from inertial sensors: Comparison to 3D marker-based motion capture.

    Science.gov (United States)

    Cahill-Rowley, Katelyn; Rose, Jessica

    2017-02-08

    Reaching is a well-practiced functional task crucial to daily living activities, and temporal-spatial measures of reaching reflect function for both adult and pediatric populations with upper-extremity motor impairments. Inertial sensors offer a mobile and inexpensive tool for clinical assessment of movement. This research outlines a method for measuring temporal-spatial reach parameters using inertial sensors, and validates these measures with traditional marker-based motion capture. 140 reaches from 10 adults, and 30 reaches from nine children aged 18-20 months, were recorded and analyzed using both inertial-sensor and motion-capture methods. Inertial sensors contained three-axis accelerometers, gyroscopes, and magnetometers. Gravitational offset of accelerometer data was measured when the sensor was at rest, and removed using sensor orientation measured at rest and throughout the reach. Velocity was calculated by numeric integration of acceleration, using a null-velocity assumption at reach start. Sensor drift was neglected given the 1-2s required for a reach. Temporal-spatial reach parameters were calculated independently for each data acquisition method. Reach path length and distance, peak velocity magnitude and timing, and acceleration at contact demonstrated consistent agreement between sensor- and motion-capture-based methods, for both adult and toddler reaches, as evaluated by intraclass correlation coefficients from 0.61 to 1.00. Taken together with actual difference between method measures, results indicate that these functional reach parameters may be reliably measured with inertial sensors. Copyright © 2016. Published by Elsevier Ltd.

  3. A COMPARISON STUDY OF DIFFERENT KERNEL FUNCTIONS FOR SVM-BASED CLASSIFICATION OF MULTI-TEMPORAL POLARIMETRY SAR DATA

    Directory of Open Access Journals (Sweden)

    B. Yekkehkhany

    2014-10-01

    Full Text Available In this paper, a framework is developed based on Support Vector Machines (SVM for crop classification using polarimetric features extracted from multi-temporal Synthetic Aperture Radar (SAR imageries. The multi-temporal integration of data not only improves the overall retrieval accuracy but also provides more reliable estimates with respect to single-date data. Several kernel functions are employed and compared in this study for mapping the input space to higher Hilbert dimension space. These kernel functions include linear, polynomials and Radial Based Function (RBF. The method is applied to several UAVSAR L-band SAR images acquired over an agricultural area near Winnipeg, Manitoba, Canada. In this research, the temporal alpha features of H/A/α decomposition method are used in classification. The experimental tests show an SVM classifier with RBF kernel for three dates of data increases the Overall Accuracy (OA to up to 3% in comparison to using linear kernel function, and up to 1% in comparison to a 3rd degree polynomial kernel function.

  4. The medial temporal lobes are critical for reward-based decision making under conditions that promote episodic future thinking.

    Science.gov (United States)

    Palombo, Daniela J; Keane, Margaret M; Verfaellie, Mieke

    2015-03-01

    In the present study, we investigated the effect of medial temporal lobe (MTL) damage on human decision making in the context of reward-based intertemporal choice. During intertemporal choice, humans typically devalue (or discount) a future reward to account for its delayed arrival (e.g., preferring $30 now over $42 in 2 months), but this effect is attenuated when participants engage in episodic future thinking, i.e., project themselves into the future to imagine a specific event. We hypothesized that this attenuation would be selectively impaired in amnesic patients, who have deficits in episodic future thinking. Replicating previous work, in a standard intertemporal choice task, amnesic patients showed temporal discounting indices similar to healthy controls. Consistent with our hypothesis, while healthy controls demonstrated attenuated temporal discounting in a condition that required participants first to engage in episodic future thinking (e.g., to imagine spending $42 at a theatre in 2 months), amnesic patients failed to demonstrate this effect. Moreover, as expected, amnesic patients' narratives were less episodically rich than those of controls. These findings extend the range of tasks that are shown to be MTL dependent to include not only memory-based decision-making tasks but also future-oriented ones. © 2014 Wiley Periodicals, Inc.

  5. Multiagent-Based Simulation of Temporal-Spatial Characteristics of Activity-Travel Patterns Using Interactive Reinforcement Learning

    Directory of Open Access Journals (Sweden)

    Min Yang

    2014-01-01

    Full Text Available We propose a multiagent-based reinforcement learning algorithm, in which the interactions between travelers and the environment are considered to simulate temporal-spatial characteristics of activity-travel patterns in a city. Road congestion degree is added to the reinforcement learning algorithm as a medium that passes the influence of one traveler’s decision to others. Meanwhile, the agents used in the algorithm are initialized from typical activity patterns extracted from the travel survey diary data of Shangyu city in China. In the simulation, both macroscopic activity-travel characteristics such as traffic flow spatial-temporal distribution and microscopic characteristics such as activity-travel schedules of each agent are obtained. Comparing the simulation results with the survey data, we find that deviation of the peak-hour traffic flow is less than 5%, while the correlation of the simulated versus survey location choice distribution is over 0.9.

  6. An analytical process of the spatio-temporal evolution of urban systems based on allometric and fractal ideas

    Energy Technology Data Exchange (ETDEWEB)

    Chen Yanguang [Department of Geography, Peking University, Beijing 100871 (China)], E-mail: chenyg@pku.edu.cn; Jiang Shiguo [Department of Geography, Peking University, Beijing 100871 (China)

    2009-01-15

    This paper presents a computer-based analytical framework for the spatio-temporal evolution of urban systems using the ideas from the allometric growth associated with fractals. Both cities as systems and systems of cities follow the law of allometric growth, and the scaling factors of the allometric relations can compose the matrix equations as eigenfunctions. The fractal dimension arrays are just the eigenvectors of the scaling factor matrices while the numbers of variables are the greatest eigenvalues. The solutions of matrix equations can be employed to analyse city systems and evaluate relative levels of urban development. The method is applied to Hangzhou urban system of China. The results reveal clearly an urbanization process characterized as population concentration and an industrialization process characterized as industrial diffusion. The computation results are consistent with the reality, which indicate that the method is available for analyzing the spatio-temporal evolution of complex systems such as cities.

  7. Quantifying relative fishing impact on fish populations based on spatio-temporal overlap of fishing effort and stock density

    DEFF Research Database (Denmark)

    Vinther, Morten; Eero, Margit

    2013-01-01

    Evaluations of the effects of management measures on fish populations are usually based on the analyses of population dynamics and estimates of fishing mortality from stock assessments. However, this approach may not be applicable in all cases, in particular for data-limited stocks, which may...... GAM analyses to predict local cod densities and combine this with spatio-temporal data of fishing effort based on VMS (Vessel Monitoring System). To quantify local fishing impact on the stock, retention probability of the gears is taken into account. The results indicate a substantial decline...

  8. Optimal Tableaux-Based Decision Procedure for Testing Satisfiability in the Alternating-Time Temporal Logic ATL+

    DEFF Research Database (Denmark)

    Cerrito, Serenella; David, Amelie; Goranko, Valentin

    2014-01-01

    We develop a sound, complete and practically implementable tableaux-based decision method for constructive satisfiability testing and model synthesis in the fragment ATL+ of the full Alternating time temporal logic ATL∗. The method extends in an essential way a previously developed tableaux......-based decision method for ATL and works in 2EXPTIME, which is the optimal worst case complexity of the satisfiability problem for ATL+. We also discuss how suitable parameterizations and syntactic restrictions on the class of input ATL+ formulae can reduce the complexity of the satisfiability problem....

  9. Modelling of trail degradation based on detailed multi-temporal digital elevation models

    Science.gov (United States)

    Tomczyk, Aleksandra; Ewertowski, Marek

    2017-04-01

    Degradation of trails adversely affects the natural environment as well as the safety and comfort of visitors. Managers of protected areas can directly impact some of the factors related to the degradation, for example, they may regulate the type of use or location of the drainage. On the other hand, they may only have an indirect impact on the other factors, e.g. through the appropriate demarcation of trails. The role of national and landscape parks is both protection of the natural environment and providing recreational opportunities. Hence, the need to obtain accurate information about the current state of the trails and the direction of their transformation is apparent. Based on multi-temporal detailed digital elevation models (DEMs) generated using topographic surveys, we proposed a simplified model of geomorphological processes which shape the surface of recreational trails. As the basis of our consideration, we adopt the idea that recreational trails and forest roads can be equated with periodic flows in the context of soil loss, transport and accumulation. Our model of trail development and degradation consists of three phases: 1) Initial phase: In this phase, anthropogenic processes play the most important role. Destroying of vegetation cover by boots and tires leads to developing of a bare trail tread which becomes vulnerable to the natural processes. When the vegetation cover is removed, soil erosion starts, hence anthropogenic processes such as trampling or damaging vegetation by tires can be regarded as preparatory processes for further development. 2) Mature phase: In this phase, natural and anthropogenic processes coexist. All areas of trail tread and its surrounding undergo transformations. Anthropogenic processes impact mainly on trail tread. Trampling leads to soil compaction in case of smooth tread or to soil relocation and loss in case of bumpy tread. Uses of hiking sticks also lead to soil loosening, similar to tires of cycles. Loosening by

  10. Understanding in-stream temporal coupling of macronutrients based on high-frequency monitoring in groundwater dominated rivers

    Science.gov (United States)

    Bieroza, M. Z.; Heathwaite, A. L.

    2012-04-01

    Developments in high-frequency water quality measurements enable capturing of fine structure of temporal variations in river biogeochemistry. Understanding of the temporal variation in the nutrient source and in-stream processes is critical in restoration of the good ecological and chemical status of river ecosystems. However, to date the in-stream temporal variability of macronutrients captured by high-frequency sampling is poorly understood (Scholefield et al., 2005; Milne et al., 2009; Harris and Heathwaite, 2011). Typically, river water quality monitoring is based on coarse sampling or storm event targeting strategies that miss the low flow water quality dynamics when in-stream processes and chemical-biological interactions may be of the greatest importance. This paper investigates the temporal dynamics and interdependencies between multiple high-frequency (hourly) nutrient and water quality time series collated for the River Leith, a tributary of the River Eden (Cumbria, UK). In-stream nutrients (total phosphorus TP, soluble reactive phosphorus SRP, nitrate nitrogen NO3N) and water quality parameters (turbidity, specific conductivity, pH, temperature, dissolved oxygen, redox potential) were measured by an automated remote mobile lab. A 54 km2 catchment of the River Leith is of mixed geology with Carboniferous limestone overlain by Penrith Sandstone and glacial till deposits. Permeable riverbed deposits create an active groundwater-surface water interface with hyporheic processes potentially exerting control over nutrient cycling. The temporal variation in in-stream nutrients and water quality variables was analysed. Diurnal patterns were observed during low flow conditions for both nutrients and water quality time series. Possible physical and biogeochemical controls on nutrients short-term dynamics were discussed. Antecedent and contemporaneous interdependencies between nutrients, water quality and hydrometric time series were explored in more detail using

  11. Auditory evoked fields elicited by spectral, temporal, and spectral-temporal changes in human cerebral cortex

    Directory of Open Access Journals (Sweden)

    Hidehiko eOkamoto

    2012-05-01

    Full Text Available Natural sounds contain complex spectral components, which are temporally modulated as time-varying signals. Recent studies have suggested that the auditory system encodes spectral and temporal sound information differently. However, it remains unresolved how the human brain processes sounds containing both spectral and temporal changes. In the present study, we investigated human auditory evoked responses elicited by spectral, temporal, and spectral-temporal sound changes by means of magnetoencephalography (MEG. The auditory evoked responses elicited by the spectral-temporal change were very similar to those elicited by the spectral change, but those elicited by the temporal change were delayed by 30 – 50 ms and differed from the others in morphology. The results suggest that human brain responses corresponding to spectral sound changes precede those corresponding to temporal sound changes, even when the spectral and temporal changes occur simultaneously.

  12. Reconstruction of Satellite-Retrieved Land-Surface Reflectance Based on Temporally-Continuous Vegetation Indices

    Directory of Open Access Journals (Sweden)

    Zhiqiang Xiao

    2015-07-01

    Full Text Available Land-surface reflectance, estimated from satellite observations through atmospheric corrections, is an essential parameter for further retrieval of various high level land-surface parameters, such as leaf area index (LAI, fraction of absorbed photosynthetically active radiation (FAPAR, and surface albedo. Although great efforts have been made, land-surface reflectance products still contain considerable noise caused by, e.g., cloud or mixed-cloud pixels, which results in temporal and spatial inconsistencies in subsequent downstream products. In this study, a new method is developed to remove the residual clouds in the Moderate Resolution Imaging Spectroradiometer (MODIS land-surface reflectance product and reconstruct time series of surface reflectance for the red, near infrared (NIR, and shortwave infrared (SWIR bands. A smoothing method is introduced to calculate upper envelopes of vegetation indices (VIs from the surface reflectance data and the cloud contaminated reflectance data are identified using the time series VIs and the upper envelopes of the time series VIs. Surface reflectance was then reconstructed according to cloud-free surface reflectance by incorporating the upper envelopes of the time series VIs as constraint conditions. The method was applied to reconstruct time series of surface reflectance from MODIS/TERRA surface reflectance product (MOD09A1. Temporal consistency analysis indicates that the new method can reconstruct temporally-continuous time series of land-surface reflectance. Comparisons with cloud-free MODIS/AQUA surface reflectance product (MYD09A1 over the BELMANIP (Benchmark Land Multisite Analysis and Intercomparison of Products sites in 2003 demonstrate that the new method provides better performance for the red band (R2 = 0.8606 and RMSE = 0.0366 and NIR band (R2 = 0.6934 and RMSE = 0.0519, than the time series cloud detection (TSCD algorithm (R2 = 0.5811 and RMSE = 0.0649; and R2 = 0.5005 and RMSE = 0

  13. Evaluation of feature selection algorithms for classification in temporal lobe epilepsy based on MR images

    Science.gov (United States)

    Lai, Chunren; Guo, Shengwen; Cheng, Lina; Wang, Wensheng; Wu, Kai

    2017-02-01

    It's very important to differentiate the temporal lobe epilepsy (TLE) patients from healthy people and localize the abnormal brain regions of the TLE patients. The cortical features and changes can reveal the unique anatomical patterns of brain regions from the structural MR images. In this study, structural MR images from 28 normal controls (NC), 18 left TLE (LTLE), and 21 right TLE (RTLE) were acquired, and four types of cortical feature, namely cortical thickness (CTh), cortical surface area (CSA), gray matter volume (GMV), and mean curvature (MCu), were explored for discriminative analysis. Three feature selection methods, the independent sample t-test filtering, the sparse-constrained dimensionality reduction model (SCDRM), and the support vector machine-recursive feature elimination (SVM-RFE), were investigated to extract dominant regions with significant differences among the compared groups for classification using the SVM classifier. The results showed that the SVM-REF achieved the highest performance (most classifications with more than 92% accuracy), followed by the SCDRM, and the t-test. Especially, the surface area and gray volume matter exhibited prominent discriminative ability, and the performance of the SVM was improved significantly when the four cortical features were combined. Additionally, the dominant regions with higher classification weights were mainly located in temporal and frontal lobe, including the inferior temporal, entorhinal cortex, fusiform, parahippocampal cortex, middle frontal and frontal pole. It was demonstrated that the cortical features provided effective information to determine the abnormal anatomical pattern and the proposed method has the potential to improve the clinical diagnosis of the TLE.

  14. Spatially and Temporally Complete Satellite Soil Moisture Data Based on a Data Assimilation Method

    Directory of Open Access Journals (Sweden)

    Zhiqiang Xiao

    2016-01-01

    Full Text Available Multiple soil moisture products have been generated from data acquired by satellite. However, these satellite soil moisture products are not spatially or temporally complete, primarily due to track changes, radio-frequency interference, dense vegetation, and frozen soil. These deficiencies limit the application of soil moisture in land surface process simulation, climatic modeling, and global change research. To fill the gaps and generate spatially and temporally complete soil moisture data, a data assimilation algorithm is proposed in this study. A soil moisture model is used to simulate soil moisture over time, and the shuffled complex evolution optimization method, developed at the University of Arizona, is used to estimate the control variables of the soil moisture model from good-quality satellite soil moisture data covering one year, so that the temporal behavior of the modeled soil moisture reaches the best agreement with the good-quality satellite soil moisture data. Soil moisture time series were then reconstructed by the soil moisture model according to the optimal values of the control variables. To analyze its performance, the data assimilation algorithm was applied to a daily soil moisture product derived from the Advanced Microwave Scanning Radiometer for the Earth Observing System (AMSR-E, the Microwave Radiometer Imager (MWRI, and the Advanced Microwave Scanning Radiometer 2 (AMSR2. Preliminary analysis using soil moisture data simulated by the Global Land Data Assimilation System (GLDAS Noah model and soil moisture measurements at a multi-scale Soil Moisture and Temperature Monitoring Network on the central Tibetan Plateau (CTP-SMTMN was performed to validate this method. The results show that the data assimilation algorithm can efficiently reconstruct spatially and temporally complete soil moisture time series. The reconstructed soil moisture data are consistent with the spatial precipitation distribution and have strong

  15. A physiologically inspired model of auditory stream segregation based on a temporal coherence analysis

    DEFF Research Database (Denmark)

    Christiansen, Simon Krogholt; Jepsen, Morten Løve; Dau, Torsten

    2012-01-01

    The ability to perceptually separate acoustic sources and focus one’s attention on a single source at a time is essential for our ability to use acoustic information. In this study, a physiologically inspired model of human auditory processing [M. L. Jepsen and T. Dau, J. Acoust. Soc. Am. 124, 422......-438, (2008)] was used as a front end of a model for auditory stream segregation. A temporal coherence analysis [M. Elhilali, C. Ling, C. Micheyl, A. J. Oxenham and S. Shamma, Neuron. 61, 317-329, (2009)] was applied at the output of the preprocessing, using the coherence across tonotopic channels to group...

  16. Spatio-Temporal Characteristics of Resident Trip Based on Poi and OD Data of Float CAR in Beijing

    Science.gov (United States)

    Mou, N.; Li, J.; Zhang, L.; Liu, W.; Xu, Y.

    2017-09-01

    Due to the influence of the urban inherent regional functional distribution, the daily activities of the residents presented some spatio-temporal patterns (periodic patterns, gathering patterns, etc.). In order to further understand the spatial and temporal characteristics of urban residents, this paper research takes the taxi trajectory data of Beijing as a sample data and studies the spatio-temporal characteristics of the residents' activities on the weekdays. At first, according to the characteristics of the taxi trajectory data distributed along the road network, it takes the Voronoi generated by the road nodes as the research unit. This paper proposes a hybrid clustering method - based on grid density, which is used to cluster the OD (origin and destination) data of taxi at different times. Then combining with the POI data of Beijing, this research calculated the density of the POI data in the clustering results, and analyzed the relationship between the activities of residents in different periods and the functional types of the region. The final results showed that the residents were mainly commuting on weekdays. And it found that the distribution of travel density showed a concentric circle of the characteristics, focusing on residential areas and work areas. The results of cluster analysis and POI analysis showed that the residents' travel had experienced the process of "spatial relative dispersion - spatial aggregation - spatial relative dispersion" in one day.

  17. SPATIO-TEMPORAL CHARACTERISTICS OF RESIDENT TRIP BASED ON POI AND OD DATA OF FLOAT CAR IN BEIJING

    Directory of Open Access Journals (Sweden)

    N. Mou

    2017-09-01

    Full Text Available Due to the influence of the urban inherent regional functional distribution, the daily activities of the residents presented some spatio-temporal patterns (periodic patterns, gathering patterns, etc.. In order to further understand the spatial and temporal characteristics of urban residents, this paper research takes the taxi trajectory data of Beijing as a sample data and studies the spatio-temporal characteristics of the residents' activities on the weekdays. At first, according to the characteristics of the taxi trajectory data distributed along the road network, it takes the Voronoi generated by the road nodes as the research unit. This paper proposes a hybrid clustering method – based on grid density, which is used to cluster the OD (origin and destination data of taxi at different times. Then,combining with the POI data of Beijing, this research calculated the density of the POI data in the clustering results, and analyzed the relationship between the activities of residents in different periods and the functional types of the region. The final results showed that the residents were mainly commuting on weekdays. And it found that the distribution of travel density showed a concentric circle of the characteristics, focusing on residential areas and work areas. The results of cluster analysis and POI analysis showed that the residents' travel had experienced the process of "spatial relative dispersion – spatial aggregation – spatial relative dispersion" in one day.

  18. Optimization of temporal networks under uncertainty

    CERN Document Server

    Wiesemann, Wolfram

    2012-01-01

    Many decision problems in Operations Research are defined on temporal networks, that is, workflows of time-consuming tasks whose processing order is constrained by precedence relations. For example, temporal networks are used to model projects, computer applications, digital circuits and production processes. Optimization problems arise in temporal networks when a decision maker wishes to determine a temporal arrangement of the tasks and/or a resource assignment that optimizes some network characteristic (e.g. the time required to complete all tasks). The parameters of these optimization probl

  19. Image Fusion-Based Change Detection for Flood Extent Extraction Using Bi-Temporal Very High-Resolution Satellite Images

    Directory of Open Access Journals (Sweden)

    Younggi Byun

    2015-08-01

    Full Text Available Change detection based on satellite images acquired from an area at different dates is of widespread interest, according to the increasing number of flood-related disasters. The images help to generate products that support emergency response and flood management at a global scale. In this paper, a novel unsupervised change detection approach based on image fusion is introduced. The approach aims to extract the reliable flood extent from very high-resolution (VHR bi-temporal images. The method takes an advantage of the spectral distortion that occurs during image fusion process to detect the change areas by flood. To this end, a change candidate image is extracted from the fused image generated with bi-temporal images by considering a local spectral distortion. This can be done by employing a universal image quality index (UIQI, which is a measure for local evaluation of spectral distortion. The decision threshold for the determination of changed pixels is set by applying a probability mixture model to the change candidate image based on expectation maximization (EM algorithm. We used bi-temporal KOMPSAT-2 satellite images to detect the flooded area in the city of N′djamena in Chad. The performance of the proposed method was visually and quantitatively compared with existing change detection methods. The results showed that the proposed method achieved an overall accuracy (OA = 75.04 close to that of the support vector machine (SVM-based supervised change detection method. Moreover, the proposed method showed a better performance in differentiating the flooded area and the permanent water body compared to the existing change detection methods.

  20. Vulnerability assessment of archaeological sites to earthquake hazard: An indicator based method integrating spatial and temporal aspects

    Directory of Open Access Journals (Sweden)

    Despina Minos-Minopoulos

    2017-07-01

    Full Text Available Across the world, numerous sites of cultural heritage value are at risk from a variety of human-induced and natural hazards such as war and earthquakes. Here we present and test a novel indicator-based method for assessing the vulnerability of archaeological sites to earthquakes. Vulnerability is approached as a dynamic element assessed through a combination of spatial and temporal parameters. The spatial parameters examine the susceptibility of the sites to the secondary Earthquake Environmental Effects of ground liquefaction, landslides and tsunami and are expressed through the Spatial Susceptibility Index (SSi. Parameters of physical vulnerability, economic importance and visitors density examine the temporal vulnerability of the sites expressed through the Temporal Vulnerability Index (TVi. The equally weighted sum of the spatial and temporal indexes represents the total Archaeological Site Vulnerability Index (A.S.V.I.. The A.S.V.I method is applied at 16 archaeological sites across Greece, allowing an assessment of their vulnerability. This then allows the establishment of a regional and national priority list for considering future risk mitigation. Results indicate that i the majority of the sites have low to moderate vulnerability to earthquake hazard, ii Neratzia Fortress on Kos and Heraion on Samos are characterised as highly vulnerable and should be prioritised for further studies and mitigation measures, and iii the majority of the sites are susceptible to at least one Earthquake Environmental Effect and present relatively high physical vulnerability attributed to the existing limited conservation works. This approach highlights the necessity for an effective vulnerability assessment methodology within the existing framework of disaster risk management for cultural heritage.

  1. Comparison of temporal realistic telecommunication base station exposure with worst-case estimation in two countries.

    Science.gov (United States)

    Mahfouz, Zaher; Verloock, Leen; Joseph, Wout; Tanghe, Emmeric; Gati, Azeddine; Wiart, Joe; Lautru, David; Hanna, Victor Fouad; Martens, Luc

    2013-12-01

    The influence of temporal daily exposure to global system for mobile communications (GSM) and universal mobile telecommunications systems and high speed downlink packet access (UMTS-HSDPA) is investigated using spectrum analyser measurements in two countries, France and Belgium. Temporal variations and traffic distributions are investigated. Three different methods to estimate maximal electric-field exposure are compared. The maximal realistic (99 %) and the maximal theoretical extrapolation factor used to extrapolate the measured broadcast control channel (BCCH) for GSM and the common pilot channel (CPICH) for UMTS are presented and compared for the first time in the two countries. Similar conclusions are found in the two countries for both urban and rural areas: worst-case exposure assessment overestimates realistic maximal exposure up to 5.7 dB for the considered example. In France, the values are the highest, because of the higher population density. The results for the maximal realistic extrapolation factor at the weekdays are similar to those from weekend days.

  2. Temporal variation and scale in movement-based resource selection functions

    Science.gov (United States)

    Hooten, M.B.; Hanks, E.M.; Johnson, D.S.; Alldredge, M.W.

    2013-01-01

    A common population characteristic of interest in animal ecology studies pertains to the selection of resources. That is, given the resources available to animals, what do they ultimately choose to use? A variety of statistical approaches have been employed to examine this question and each has advantages and disadvantages with respect to the form of available data and the properties of estimators given model assumptions. A wealth of high resolution telemetry data are now being collected to study animal population movement and space use and these data present both challenges and opportunities for statistical inference. We summarize traditional methods for resource selection and then describe several extensions to deal with measurement uncertainty and an explicit movement process that exists in studies involving high-resolution telemetry data. Our approach uses a correlated random walk movement model to obtain temporally varying use and availability distributions that are employed in a weighted distribution context to estimate selection coefficients. The temporally varying coefficients are then weighted by their contribution to selection and combined to provide inference at the population level. The result is an intuitive and accessible statistical procedure that uses readily available software and is computationally feasible for large datasets. These methods are demonstrated using data collected as part of a large-scale mountain lion monitoring study in Colorado, USA.

  3. EMD-Based Temporal and Spectral Features for the Classification of EEG Signals Using Supervised Learning.

    Science.gov (United States)

    Riaz, Farhan; Hassan, Ali; Rehman, Saad; Niazi, Imran Khan; Dremstrup, Kim

    2016-01-01

    This paper presents a novel method for feature extraction from electroencephalogram (EEG) signals using empirical mode decomposition (EMD). Its use is motivated by the fact that the EMD gives an effective time-frequency analysis of nonstationary signals. The intrinsic mode functions (IMF) obtained as a result of EMD give the decomposition of a signal according to its frequency components. We present the usage of upto third order temporal moments, and spectral features including spectral centroid, coefficient of variation and the spectral skew of the IMFs for feature extraction from EEG signals. These features are physiologically relevant given that the normal EEG signals have different temporal and spectral centroids, dispersions and symmetries when compared with the pathological EEG signals. The calculated features are fed into the standard support vector machine (SVM) for classification purposes. The performance of the proposed method is studied on a publicly available dataset which is designed to handle various classification problems including the identification of epilepsy patients and detection of seizures. Experiments show that good classification results are obtained using the proposed methodology for the classification of EEG signals. Our proposed method also compares favorably to other state-of-the-art feature extraction methods.

  4. SUPPORT VECTOR MACHINE CLASSIFICATION OF OBJECT-BASED DATA FOR CROP MAPPING, USING MULTI-TEMPORAL LANDSAT IMAGERY

    Directory of Open Access Journals (Sweden)

    R. Devadas

    2012-07-01

    Full Text Available Crop mapping and time series analysis of agronomic cycles are critical for monitoring land use and land management practices, and analysing the issues of agro-environmental impacts and climate change. Multi-temporal Landsat data can be used to analyse decadal changes in cropping patterns at field level, owing to its medium spatial resolution and historical availability. This study attempts to develop robust remote sensing techniques, applicable across a large geographic extent, for state-wide mapping of cropping history in Queensland, Australia. In this context, traditional pixel-based classification was analysed in comparison with image object-based classification using advanced supervised machine-learning algorithms such as Support Vector Machine (SVM. For the Darling Downs region of southern Queensland we gathered a set of Landsat TM images from the 2010–2011 cropping season. Landsat data, along with the vegetation index images, were subjected to multiresolution segmentation to obtain polygon objects. Object-based methods enabled the analysis of aggregated sets of pixels, and exploited shape-related and textural variation, as well as spectral characteristics. SVM models were chosen after examining three shape-based parameters, twenty-three textural parameters and ten spectral parameters of the objects. We found that the object-based methods were superior to the pixel-based methods for classifying 4 major landuse/land cover classes, considering the complexities of within field spectral heterogeneity and spectral mixing. Comparative analysis clearly revealed that higher overall classification accuracy (95% was observed in the object-based SVM compared with that of traditional pixel-based classification (89% using maximum likelihood classifier (MLC. Object-based classification also resulted speckle-free images. Further, object-based SVM models were used to classify different broadacre crop types for summer and winter seasons. The influence of

  5. Tableaux-Based Decision Method for Single-Agent Linear Time Synchronous Temporal Epistemic Logics with Interacting Time and Knowledge

    DEFF Research Database (Denmark)

    Ajspur, Mai; Goranko, Valentin

    2013-01-01

    interactions between time and knowledge, such as synchrony and agents' abilities for learning and recall. In this work we develop practically implementable tableau-based decision procedures for deciding satisfiability in single-agent synchronous temporal-epistemic logics with interactions between time...... and knowledge. We discuss some complications that occur, even in the single-agent case, when interactions between time and knowledge are assumed and show how the method of incremental tableaux can be adapted to work in EXPSPACE, respectively 2EXPTIME, for these logics, thereby also matching the upper bounds...

  6. GPU-based Low-dose 4DCT Reconstruction via Temporal Non-local Means

    CERN Document Server

    Tian, Zhen; Jiang, Steve B

    2010-01-01

    Four-dimensional computed tomography (4DCT) has been widely used in cancer radiotherapy for accurate target delineation and motion measurement for tumors in thorax and upper abdomen areas. However, 4DCT simulation is associated with much higher imaging dose than conventional CT simulation, which is a major concern in its clinical application. Conventionally, each phase of 4DCT is reconstructed independently using the filtered backprojection (FBP) algorithm. The basic idea of our new algorithm is that, by utilizing the common information among different phases, the input information required to reconstruct image of high quality, and thus the imaging dose, can be reduced. We proposed a temporal non-local means (TNLM) method to explore the inter-phase similarity. All phases of the 4DCT images are reconstructed simultaneously by minimizing a cost function consisting of a data fidelity term and a TNLM regularization term. We utilized a forward-backward splitting algorithm and a Gauss-Jacobi iteration method to eff...

  7. Temporal profiling of the adipocyte proteome during differentiation using a five-plex SILAC based strategy

    DEFF Research Database (Denmark)

    Molina, Henrik; Yang, Yi; Ruch, Travis

    2009-01-01

    The adipose tissue has important secretory and endocrine functions in humans. The regulation of adipocyte differentiation has been actively pursued using transcriptomic methods over the last several years. Quantitative proteomics has emerged as a promising approach to obtain temporal profiles...... of arginine to study the nuclear proteome and the secretome during the course of adipocyte differentiation. Tandem mass spectrometry analysis using a quadrupole time-of-flight instrument resulted in identification of a total 882 proteins from these two proteomes. Of these proteins, 427 were identified...... adipocyte differentiation has not been documented previously. For example, THO complex 4, a context-dependent transcriptional activator in the T-cell receptor alpha enhancer complex, showed highest expression at middle stage of adipogenesis, while SNF2 alpha, a chromatin remodeling protein...

  8. A foundation for flow-based matching: using temporal logic and model checking

    DEFF Research Database (Denmark)

    Brunel, Julien Pierre Manuel; Doligez, Damien; Hansen, René Rydhof

    2009-01-01

    within different control-flow paths, and a notion of witnesses that record such existential bindings for use in the subsequent program transformation process. We formalize CTL-VW and describe its use in the context of Coccinelle. We then assess the performance of the approach in practice, using......Reasoning about program control-flow paths is an important functionality of a number of recent program matching languages and associated searching and transformation tools. Temporal logic provides a well-defined means of expressing properties of control-flow paths in programs, and indeed...... with variables and witnesses) that is a suitable basis for the semantics and implementation of the Coccinelle’s program matching language. Our extension to CTL includes existential quantification over program fragments, which allows metavariables in the program matching language to range over different values...

  9. A Foundation for Flow-Based Program Matching Using Temporal Logic and Model Checking

    DEFF Research Database (Denmark)

    Brunel, Julien Pierre Manuel; Doligez, Damien; Hansen, Rene Rydhof

    2008-01-01

    different values within different control-flow paths, and a notion of witnesses that record such existential bindings for use in the subsequent program transformation process. We formalize CTL-VW and describe its use in the context of Coccinelle. We then assess the performance of the approach in practice......Reasoning about program control-flow paths is an important functionality of a number of recent program matching languages and associated searching and transformation tools. Temporal logic provides a well-defined means of expressing properties of control-flow paths in programs, and indeed......-VW (CTL with variables and witnesses) that is a suitable basis for the semantics and implementation of the Coccinelle’s program matching language. Our extension to CTL includes existential quantification over program fragments, which allows metavariables in the program matching language to range over...

  10. Ultra-short electron beams based spatio-temporal radiation biology and radiotherapy.

    Science.gov (United States)

    Malka, Victor; Faure, Jérôme; Gauduel, Yann A

    2010-01-01

    Deeply understanding the basic mechanisms of radiation damage in vitro and on living cells, starting from the early radical and molecular processes to mutagenic DNA lesions, cell signalling, genomic instability, apoptosis, microenvironment and Bystander effects, radio sensitivity should have many practical consequences such as the customization of cancer radiotherapy or radioprotection protocols. In this context, innovative laser-plasma accelerators provide ultra-short particle beams (electrons, protons) with parameters of interest for radiation biology and medical physics. This review article approaches some complex links that exist between radiation physics of new pulsed irradiation sources and potential biomedical applications. These links concern mainly the understanding of spatio-temporal events triggered by a radiation, within a fluctuating lapse of time from the initial energy deposition to primary damages of biological interest. 2010 Elsevier B.V. All rights reserved.

  11. Visulization of Time-Varying Multiresolution Date Using Error-Based Temporal-Spatial Resuse

    Energy Technology Data Exchange (ETDEWEB)

    Nuber, C; LaMar, E; Hamann, B; Joy, K

    2002-04-22

    In this paper, we report results on exploration of two-dimensional (2D) time varying datasets. We extend the notion of multiresolution spatial data approximation of static datasets to spatio-temporal approximation of time-varying datasets. Time-varying datasets typically do not change ''uniformly,'' i.e., some spatial sub-domains can experience only little or no change for extended periods of time. In these sub-domains, we show that approximation error bounds can be met when using sub-domains from other time-steps effectively. We generate a more general approximation scheme where sub-domains may approximate congruent sub-domains from any other time steps. While this incurs an O(T2) overhead, where T is the total number of time-steps, we show significant reduction in data transmission. We also discuss ideas for improvements to reduce overhead.

  12. Temporal and Spatial Analysis of Precipitation in Guizhou Based on TRMM 3B42 Satellite Data

    Science.gov (United States)

    Wu, Jianfeng; Zhang, Fengtai; Cao, Guangjie; Li, Wei; Zhao, Xuemei

    2017-08-01

    Precipitation is an important part of the earth’s climate system. This article makes full use of the advantages of remote sensing images. In this paper, the TRMM 3B42 satellite precipitation from 1998 to 2013 is selected as the data source and Guizhou Province as the research area. The temporal and spatial distribution characteristics of precipitation in Guizhou Province are studied by linear trend estimation, linear regression analysis and ArcGIS spatial analysis. The conclusion as below: Precipitation shows a decreasing trend from southeast to northwest in Guizhou Province. From the seasonal scale, Precipitation is mainly concentrated in summer and the least precipitation in winter. Over the past 16 years, precipitation in Guizhou Province has shown a fluctuating change. Summer precipitation trend is more obvious. And winter precipitation is not obvious.

  13. Methodology for heritage conservation in Belgium based on multi-temporal interferometry

    Science.gov (United States)

    Bejarano-Urrego, L.; Verstrynge, E.; Shimoni, M.; Lopez, J.; Walstra, J.; Declercq, P.-Y.; Derauw, D.; Hayen, R.; Van Balen, K.

    2017-09-01

    Soil differential settlements that cause structural damage to heritage buildings are precipitating cultural and economic value losses. Adequate damage assessment as well as protection and preservation of the built patrimony are priorities at national and local levels, so they require advanced integration and analysis of environmental, architectural and historical parameters. The GEPATAR project (GEotechnical and Patrimonial Archives Toolbox for ARchitectural conservation in Belgium) aims to create an online interactive geo-information tool that allows the user to view and to be informed about the Belgian heritage buildings at risk due to differential soil settlements. Multi-temporal interferometry techniques (MTI) have been proven to be a powerful technique for analyzing earth surface deformation patterns through time series of Synthetic Aperture Radar (SAR) images. These techniques allow to measure ground movements over wide areas at high precision and relatively low cost. In this project, Persistent Scatterer Synthetic Aperture Radar Interferometry (PS-InSAR) and Multidimensional Small Baseline Subsets (MSBAS) are used to measure and monitor the temporal evolution of surface deformations across Belgium. This information is integrated with the Belgian heritage data by means of an interactive toolbox in a GIS environment in order to identify the level of risk. At country scale, the toolbox includes ground deformation hazard maps, geological information, location of patrimony buildings and land use; while at local scale, it includes settlement rates, photographic and historical surveys as well as architectural and geotechnical information. Some case studies are investigated by means of on-site monitoring techniques and stability analysis to evaluate the applied approaches. This paper presents a description of the methodology being implemented in the project together with the case study of the Saint Vincent's church which is located on a former colliery zone. For

  14. Ground-based measurements of spatial and temporal variability of snow accumulation in East Antarctica

    Science.gov (United States)

    Eisen, Olaf; Frezzotti, Massimo; Genthon, Christophe; Isaksson, Elisabeth; Magand, Olivier; van den Broeke, Michiel R.; Dixon, Daniel A.; Ekaykin, Alexey; Holmlund, Per; Kameda, Takao; KarlöF, Lars; Kaspari, Susan; Lipenkov, Vladimir Y.; Oerter, Hans; Takahashi, Shuhei; Vaughan, David G.

    2008-06-01

    The East Antarctic Ice Sheet is the largest, highest, coldest, driest, and windiest ice sheet on Earth. Understanding of the surface mass balance (SMB) of Antarctica is necessary to determine the present state of the ice sheet, to make predictions of its potential contribution to sea level rise, and to determine its past history for paleoclimatic reconstructions. However, SMB values are poorly known because of logistic constraints in extreme polar environments, and they represent one of the biggest challenges of Antarctic science. Snow accumulation is the most important parameter for the SMB of ice sheets. SMB varies on a number of scales, from small-scale features (sastrugi) to ice-sheet-scale SMB patterns determined mainly by temperature, elevation, distance from the coast, and wind-driven processes. In situ measurements of SMB are performed at single points by stakes, ultrasonic sounders, snow pits, and firn and ice cores and laterally by continuous measurements using ground-penetrating radar. SMB for large regions can only be achieved practically by using remote sensing and/or numerical climate modeling. However, these techniques rely on ground truthing to improve the resolution and accuracy. The separation of spatial and temporal variations of SMB in transient regimes is necessary for accurate interpretation of ice core records. In this review we provide an overview of the various measurement techniques, related difficulties, and limitations of data interpretation; describe spatial characteristics of East Antarctic SMB and issues related to the spatial and temporal representativity of measurements; and provide recommendations on how to perform in situ measurements.

  15. Spatio-Temporal Data Analysis at Scale Using Models Based on Gaussian Processes

    Energy Technology Data Exchange (ETDEWEB)

    Stein, Michael [Univ. of Chicago, IL (United States)

    2017-03-13

    Gaussian processes are the most commonly used statistical model for spatial and spatio-temporal processes that vary continuously. They are broadly applicable in the physical sciences and engineering and are also frequently used to approximate the output of complex computer models, deterministic or stochastic. We undertook research related to theory, computation, and applications of Gaussian processes as well as some work on estimating extremes of distributions for which a Gaussian process assumption might be inappropriate. Our theoretical contributions include the development of new classes of spatial-temporal covariance functions with desirable properties and new results showing that certain covariance models lead to predictions with undesirable properties. To understand how Gaussian process models behave when applied to deterministic computer models, we derived what we believe to be the first significant results on the large sample properties of estimators of parameters of Gaussian processes when the actual process is a simple deterministic function. Finally, we investigated some theoretical issues related to maxima of observations with varying upper bounds and found that, depending on the circumstances, standard large sample results for maxima may or may not hold. Our computational innovations include methods for analyzing large spatial datasets when observations fall on a partially observed grid and methods for estimating parameters of a Gaussian process model from observations taken by a polar-orbiting satellite. In our application of Gaussian process models to deterministic computer experiments, we carried out some matrix computations that would have been infeasible using even extended precision arithmetic by focusing on special cases in which all elements of the matrices under study are rational and using exact arithmetic. The applications we studied include total column ozone as measured from a polar-orbiting satellite, sea surface temperatures over the

  16. A Framework of Temporal-Spatial Descriptors-Based Feature Extraction for Improved Myoelectric Pattern Recognition.

    Science.gov (United States)

    Khushaba, Rami N; Al-Timemy, Ali H; Al-Ani, Ahmed; Al-Jumaily, Adel

    2017-10-01

    The extraction of the accurate and efficient descriptors of muscular activity plays an important role in tackling the challenging problem of myoelectric control of powered prostheses. In this paper, we present a new feature extraction framework that aims to give an enhanced representation of muscular activities through increasing the amount of information that can be extracted from individual and combined electromyogram (EMG) channels. We propose to use time-domain descriptors (TDDs) in estimating the EMG signal power spectrum characteristics; a step that preserves the computational power required for the construction of spectral features. Subsequently, TDD is used in a process that involves: 1) representing the temporal evolution of the EMG signals by progressively tracking the correlation between the TDD extracted from each analysis time window and a nonlinearly mapped version of it across the same EMG channel and 2) representing the spatial coherence between the different EMG channels, which is achieved by calculating the correlation between the TDD extracted from the differences of all possible combinations of pairs of channels and their nonlinearly mapped versions. The proposed temporal-spatial descriptors (TSDs) are validated on multiple sparse and high-density (HD) EMG data sets collected from a number of intact-limbed and amputees performing a large number of hand and finger movements. Classification results showed significant reductions in the achieved error rates in comparison to other methods, with the improvement of at least 8% on average across all subjects. Additionally, the proposed TSDs achieved significantly well in problems with HD-EMG with average classification errors of <5% across all subjects using windows lengths of 50 ms only.

  17. High-Temporal-Resolution High-Spatial-Resolution Spaceborne SAR Based on Continuously Varying PRF.

    Science.gov (United States)

    Men, Zhirong; Wang, Pengbo; Li, Chunsheng; Chen, Jie; Liu, Wei; Fang, Yue

    2017-07-25

    Synthetic Aperture Radar (SAR) is a well-established and powerful imaging technique for acquiring high-spatial-resolution images of the Earth's surface. With the development of beam steering techniques, sliding spotlight and staring spotlight modes have been employed to support high-spatial-resolution applications. In addition to this strengthened high-spatial-resolution and wide-swath capability, high-temporal-resolution (short repeat-observation interval) represents a key capability for numerous applications. However, conventional SAR systems are limited in that the same patch can only be illuminated for several seconds within a single pass. This paper considers a novel high-squint-angle system intended to acquire high-spatial-resolution spaceborne SAR images with repeat-observation intervals varying from tens of seconds to several minutes within a single pass. However, an exponentially increased range cell migration would arise and lead to a conflict between the receive window and 'blind ranges'. An efficient data acquisition technique for high-temporal-resolution, high-spatial-resolution and high-squint-angle spaceborne SAR, in which the pulse repetition frequency (PRF) is continuously varied according to the changing slant range, is presented in this paper. This technique allows echo data to remain in the receive window instead of conflicting with the transmitted pulse or nadir echo. Considering the precision of hardware, a compromise and practical strategy is also proposed. Furthermore, a detailed performance analysis of range ambiguities is provided with respect to parameters of TerraSAR-X. For strong point-like targets, the range ambiguity of this technique would be better than that of uniform PRF technique. For this innovative technique, a resampling strategy and modified imaging algorithm have been developed to handle the non-uniformly sampled echo data. Simulations are performed to validate the efficiency of the proposed technique and the associated

  18. Spatio-Temporal Simulation and Analysis of Regional Ecological Security Based on Lstm

    Science.gov (United States)

    Gong, C.; Qi, L.; Heming, L.; Karimian, H.; Yuqin, M.

    2017-10-01

    Region is a complicated system, where human, nature and society interact and influence. Quantitative modeling and simulation of ecology in the region are the key to realize the strategy of regional sustainable development. Traditional machine learning methods have made some achievements in the modeling of regional ecosystems, but it is difficult to determine the learning characteristics and to realize spatio-temporal simulation. Deep learning does not need prior identification of training characteristics, have excellent feature learning ability, can improve the accuracy of model prediction, so the use of deep learning model has a significant advantage. Therefore, we use net primary productivity (NPP), atmospheric optical depth (AOD), moderate-resolution imaging spectrometer (MODIS), Normalized Difference Vegetation Index (NDVI), landcover and population data, and use LSTM to do spatio-temporal simulation. We conduct spatial analysis and driving force analysis. The conclusions are as follows: the ecological deficit of northwestern Henan and urban communities such as Zhengzhou is higher. The reason of former lies in the weak land productivity of the Loess Plateau, the irrational crop cultivation mode. The latter lies in the high consumption of resources in the large urban agglomeration; The positive trend of Henan ecological development from 2013 is mainly due to the effective environmental protection policy in the 12th five-year plan; The main driver of the sustained ecological deficit growth of Henan in 2004-2013 is high-speed urbanization, increasing population and goods consumption. This article provides relevant basic scientific support and reference for the regional ecological scientific management and construction.

  19. ANALYSIS OF SPATIO-TEMPORAL TRAFFIC PATTERNS BASED ON PEDESTRIAN TRAJECTORIES

    Directory of Open Access Journals (Sweden)

    S. Busch

    2016-06-01

    Full Text Available For driver assistance and autonomous driving systems, it is essential to predict the behaviour of other traffic participants. Usually, standard filter approaches are used to this end, however, in many cases, these are not sufficient. For example, pedestrians are able to change their speed or direction instantly. Also, there may be not enough observation data to determine the state of an object reliably, e.g. in case of occlusions. In those cases, it is very useful if a prior model exists, which suggests certain outcomes. For example, it is useful to know that pedestrians are usually crossing the road at a certain location and at certain times. This information can then be stored in a map which then can be used as a prior in scene analysis, or in practical terms to reduce the speed of a vehicle in advance in order to minimize critical situations. In this paper, we present an approach to derive such a spatio-temporal map automatically from the observed behaviour of traffic participants in everyday traffic situations. In our experiments, we use one stationary camera to observe a complex junction, where cars, public transportation and pedestrians interact. We concentrate on the pedestrians trajectories to map traffic patterns. In the first step, we extract trajectory segments from the video data. These segments are then clustered in order to derive a spatial model of the scene, in terms of a spatially embedded graph. In the second step, we analyse the temporal patterns of pedestrian movement on this graph. We are able to derive traffic light sequences as well as the timetables of nearby public transportation. To evaluate our approach, we used a 4 hour video sequence. We show that we are able to derive traffic light sequences as well as time tables of nearby public transportation.

  20. Analysis of Spatio-Temporal Traffic Patterns Based on Pedestrian Trajectories

    Science.gov (United States)

    Busch, S.; Schindler, T.; Klinger, T.; Brenner, C.

    2016-06-01

    For driver assistance and autonomous driving systems, it is essential to predict the behaviour of other traffic participants. Usually, standard filter approaches are used to this end, however, in many cases, these are not sufficient. For example, pedestrians are able to change their speed or direction instantly. Also, there may be not enough observation data to determine the state of an object reliably, e.g. in case of occlusions. In those cases, it is very useful if a prior model exists, which suggests certain outcomes. For example, it is useful to know that pedestrians are usually crossing the road at a certain location and at certain times. This information can then be stored in a map which then can be used as a prior in scene analysis, or in practical terms to reduce the speed of a vehicle in advance in order to minimize critical situations. In this paper, we present an approach to derive such a spatio-temporal map automatically from the observed behaviour of traffic participants in everyday traffic situations. In our experiments, we use one stationary camera to observe a complex junction, where cars, public transportation and pedestrians interact. We concentrate on the pedestrians trajectories to map traffic patterns. In the first step, we extract trajectory segments from the video data. These segments are then clustered in order to derive a spatial model of the scene, in terms of a spatially embedded graph. In the second step, we analyse the temporal patterns of pedestrian movement on this graph. We are able to derive traffic light sequences as well as the timetables of nearby public transportation. To evaluate our approach, we used a 4 hour video sequence. We show that we are able to derive traffic light sequences as well as time tables of nearby public transportation.

  1. The Kosovo Precedent in the Secession and Recognition of Crimea

    Directory of Open Access Journals (Sweden)

    Dr.Sc. Elvina Jusufaj

    2015-06-01

    Full Text Available Crimea’s secession from Ukraine and its annexation to the Russian Federation invoked Kosovo precedent, in its declaration of independence, as an argument for secession. The territorial referendum in the Autonomous Republic of Crimea, only five days after the declaration of independence, was an attempt to justify the secession based on the right to selfdetermination of the people of Crimea. It is overwhelmingly considered illegal and its outcome has not been accepted and recognized by states, regional and international organizations. The comparative elements of statehood and secession between Kosovo and Crimea are reflected through analyzing the declarations of independence, international recognition and Russia’s role as a third-state factor in external selfdetermination. Essential distinctions are highlighted. Kosovo is widely acknowledged and accepted a sui generis case. Its declaration of independence came as result of a long monitored comprehensive process; not to legitimize the right for self-determination but as the final option for stability and peace in the region. Crimea seceded in violation of international law through the use of force. While Kosovo is a democratic, multi-ethnic new state and recognized by 107 states, the secession of Crimea and its annexation to the Russian Federation is considered illegal and endangers the existing international order.

  2. Dynamic hydrolase activities precede hypersensitive tissue collapse in tomato seedlings.

    Science.gov (United States)

    Sueldo, Daniela; Ahmed, Ali; Misas-Villamil, Johana; Colby, Tom; Tameling, Wladimir; Joosten, Matthieu H A J; van der Hoorn, Renier A L

    2014-08-01

    Hydrolases such as subtilases, vacuolar processing enzymes (VPEs) and the proteasome play important roles during plant programmed cell death (PCD). We investigated hydrolase activities during PCD using activity-based protein profiling (ABPP), which displays the active proteome using probes that react covalently with the active site of proteins. We employed tomato (Solanum lycopersicum) seedlings undergoing synchronized hypersensitive cell death by co-expressing the avirulence protein Avr4 from Cladosporium fulvum and the tomato resistance protein Cf-4. Cell death is blocked in seedlings grown at high temperature and humidity, and is synchronously induced by decreasing temperature and humidity. ABPP revealed that VPEs and the proteasome are not differentially active, but that activities of papain-like cysteine proteases and serine hydrolases, including Hsr203 and P69B, increase before hypersensitive tissue collapse, whereas the activity of a carboxypeptidase-like enzyme is reduced. Similar dynamics were observed for these enzymes in the apoplast of tomato challenged with C. fulvum. Unexpectedly, these challenged plants also displayed novel isoforms of secreted putative VPEs. In the absence of tissue collapse at high humidity, the hydrolase activity profile is already altered completely, demonstrating that changes in hydrolase activities precede hypersensitive tissue collapse. © 2014 The Authors New Phytologist © 2014 New Phytologist Trust.

  3. Indeterministic Temporal Logic

    Directory of Open Access Journals (Sweden)

    Trzęsicki Kazimierz

    2015-09-01

    Full Text Available The questions od determinism, causality, and freedom have been the main philosophical problems debated since the beginning of temporal logic. The issue of the logical value of sentences about the future was stated by Aristotle in the famous tomorrow sea-battle passage. The question has inspired Łukasiewicz’s idea of many-valued logics and was a motive of A. N. Prior’s considerations about the logic of tenses. In the scheme of temporal logic there are different solutions to the problem. In the paper we consider indeterministic temporal logic based on the idea of temporal worlds and the relation of accessibility between them.

  4. Temporal trends in obesity, osteoporosis treatment, bone mineral density, and fracture rates: a population-based historical cohort study.

    Science.gov (United States)

    Leslie, William D; Lix, Lisa M; Yogendran, Marina S; Morin, Suzanne N; Metge, Colleen J; Majumdar, Sumit R

    2014-04-01

    Diverging international trends in fracture rates have been observed, with most reports showing that fracture rates have stabilized or decreased in North American and many European populations. We studied two complementary population-based historical cohorts from the Province of Manitoba, Canada (1996-2006) to determine whether declining osteoporotic fracture rates in Canada are attributable to trends in obesity, osteoporosis treatment, or bone mineral density (BMD). The Population Fracture Registry included women aged 50 years and older with major osteoporotic fractures, and was used to assess impact of changes in osteoporosis treatment. The BMD Registry included all women aged 50 years and older undergoing BMD tests, and was used to assess impact of changes in obesity and BMD. Model-based estimates of temporal changes in fracture rates (Fracture Registry) were calculated. Temporal changes in obesity and BMD and their association with fracture rates (BMD Registry) were estimated. In the Fracture Registry (n=27,341), fracture rates declined 1.6% per year (95% confidence interval [CI], 1.3% to 2.0%). Although osteoporosis treatment increased from 5.6% to 17.4%, the decline in fractures was independent of osteoporosis treatment. In the BMD Registry (n=36,587), obesity increased from 12.7% to 27.4%. Femoral neck BMD increased 0.52% per year and lumbar spine BMD increased 0.32% per year after covariate adjustment (pobesity or osteoporosis treatment. © 2014 American Society for Bone and Mineral Research.

  5. Biochemical increase in phosphorylated alpha-synuclein precedes histopathology of Lewy-type synucleinopathies.

    Science.gov (United States)

    Lue, Lih-Fen; Walker, Douglas G; Adler, Charles H; Shill, Holly; Tran, Hung; Akiyama, Haruhiko; Sue, Lucia I; Caviness, John; Sabbagh, Marwan N; Beach, Thomas G

    2012-11-01

    A key component in Lewy body (LB) pathology in LB disorders is α-synuclein phosphorylated at serine 129 (pαsyn). However, it is not known if increase in the level of biochemically measurable pαsyn precedes the presence of histologically identified Lewy-type synucleinopathy (LTS). To gain sights into possible temporal sequence, we measured levels of pαsyn in cingulate and temporal cortices that develop LTS pathology at later stages of LB disorders. Brain homogenates from 128 autopsy cases including normal controls and subjects classified by Unified LTS histopathology staging system were studied. We found that biochemically measurable pαsyn levels in cingulate and temporal cortices were significantly increased at Unified stages III and IV. When pαsyn levels were compared between LTS density scores instead of Unified stages, significant increases were detected even as LTS density scores increased from 0 to 1 in olfactory bulb and substantia nigra. Therefore, our findings demonstrated that changes of pαsyn levels in cingulate and temporal cortices coincided with the early appearance of the LTS pathology in olfactory bulb and substantia nigra, even though histologically demonstrable LTS was lacking in the cortical region. Therefore, identifying the underlying mechanisms driving these changes could be crucial to understanding the pathogenesis of LB disorders. © 2012 The Authors; Brain Pathology © 2012 International Society of Neuropathology.

  6. Dim small targets detection based on self-adaptive caliber temporal-spatial filtering

    Science.gov (United States)

    Fan, Xiangsuo; Xu, Zhiyong; Zhang, Jianlin; Huang, Yongmei; Peng, Zhenming

    2017-09-01

    To boost the detect ability of dim small targets, this paper began by using improved anisotropy for background prediction (IABP), followed by target enhancement by improved high-order cumulates (HQS). Finally, on the basis of image pre-processing, to address the problem of missed and wrong detection caused by fixed caliber of traditional pipeline filtering, this paper used targets' multi-frame movement correlation in the time-space domain, combined with the scale-space theory, to propose a temporal-spatial filtering algorithm which allows the caliber to make self-adaptive changes according to the changes of the targets' scale, effectively solving the detection-related issues brought by unchanged caliber and decreased/increased size of the targets. Experiments showed that the improved anisotropic background predication could be loyal to the true background of the original image to the maximum extent, presenting a superior overall performance to other background prediction methods; the improved HQS significantly increased the signal-noise ratio of images; when the signal-noise ratio was lower than 2.6 dB, this detection algorithm could effectively eliminate noise and detect targets. For the algorithm, the lowest signal-to-noise ratio of the detectable target is 0.37.

  7. A Multi-Band Uncertainty Set Based Robust SCUC With Spatial and Temporal Budget Constraints

    Energy Technology Data Exchange (ETDEWEB)

    Dai, Chenxi; Wu, Lei; Wu, Hongyu

    2016-11-01

    The dramatic increase of renewable energy resources in recent years, together with the long-existing load forecast errors and increasingly involved price sensitive demands, has introduced significant uncertainties into power systems operation. In order to guarantee the operational security of power systems with such uncertainties, robust optimization has been extensively studied in security-constrained unit commitment (SCUC) problems, for immunizing the system against worst uncertainty realizations. However, traditional robust SCUC models with single-band uncertainty sets may yield over-conservative solutions in most cases. This paper proposes a multi-band robust model to accurately formulate various uncertainties with higher resolution. By properly tuning band intervals and weight coefficients of individual bands, the proposed multi-band robust model can rigorously and realistically reflect spatial/temporal relationships and asymmetric characteristics of various uncertainties, and in turn could effectively leverage the tradeoff between robustness and economics of robust SCUC solutions. The proposed multi-band robust SCUC model is solved by Benders decomposition (BD) and outer approximation (OA), while taking the advantage of integral property of the proposed multi-band uncertainty set. In addition, several accelerating techniques are developed for enhancing the computational performance and the convergence speed. Numerical studies on a 6-bus system and the modified IEEE 118-bus system verify the effectiveness of the proposed robust SCUC approach for enhancing uncertainty modeling capabilities and mitigating conservativeness of the robust SCUC solution.

  8. Stochastic Urban Pluvial Flood Hazard Maps Based upon a Spatial-Temporal Rainfall Generator

    Directory of Open Access Journals (Sweden)

    Nuno Eduardo Simões

    2015-06-01

    Full Text Available It is a common practice to assign the return period of a given storm event to the urban pluvial flood event that such storm generates. However, this approach may be inappropriate as rainfall events with the same return period can produce different urban pluvial flooding events, i.e., with different associated flood extent, water levels and return periods. This depends on the characteristics of the rainfall events, such as spatial variability, and on other characteristics of the sewer system and the catchment. To address this, the paper presents an innovative contribution to produce stochastic urban pluvial flood hazard maps. A stochastic rainfall generator for urban-scale applications was employed to generate an ensemble of spatially—and temporally—variable design storms with similar return period. These were used as input to the urban drainage model of a pilot urban catchment (~9 km2 located in London, UK. Stochastic flood hazard maps were generated through a frequency analysis of the flooding generated by the various storm events. The stochastic flood hazard maps obtained show that rainfall spatial-temporal variability is an important factor in the estimation of flood likelihood in urban areas. Moreover, as compared to the flood hazard maps obtained by using a single spatially-uniform storm event, the stochastic maps generated in this study provide a more comprehensive assessment of flood hazard which enables better informed flood risk management decisions.

  9. Information Mining of Spatio-Temporal Evolution of Lakes Based on Multiple Dynamic Measurements

    Science.gov (United States)

    Feng, W.; Chen, J.

    2017-09-01

    Lakes are important water resources and integral parts of the natural ecosystem, and it is of great significance to study the evolution of lakes. The area of each lake increased and decreased at the same time in natural condition, only but the net change of lakes' area is the result of the bidirectional evolution of lakes. In this paper, considering the effects of net fragmentation, net attenuation, swap change and spatial invariant part in lake evolution, a comprehensive evaluation indexes of lake dynamic evolution were defined,. Such degree contains three levels of measurement: 1) the swap dynamic degree (SDD) reflects the space activity of lakes in the study period. 2) the attenuation dynamic degree (ADD) reflects the net attenuation of lakes into non-lake areas. 3) the fragmentation dynamic degree (FDD) reflects the trend of lakes to be divided and broken into smaller lakes. Three levels of dynamic measurement constitute the three-dimensional "Swap - attenuation - fragmentation" dynamic evolution measurement system of lakes. To show its effectiveness, the dynamic measurement was applied to lakes in Jianghan Plain, the middle Yangtze region of China for a more detailed analysis of lakes from 1984 to 2014. In combination with spatial-temporal location characteristics of lakes, the hidden information in lake evolution in the past 30 years can be revealed.

  10. Dynamic computed tomography based on spatio-temporal analysis in acute stroke: Preliminary study

    Energy Technology Data Exchange (ETDEWEB)

    Park, Ha Young; Pyeon, Do Yeong; Kim, Da Hye; Jung, Young Jin [Dongseo University, Busan (Korea, Republic of)

    2016-12-15

    Acute stroke is a one of common disease that require fast diagnosis and treatment to save patients life. however, the acute stroke may cause lifelong disability due to brain damage with no prompt surgical procedure. In order to diagnose the Stroke, brain perfusion CT examination and possible rapid implementation of 3D angiography has been widely used. However, a low-dose technique should be applied for the examination since a lot of radiation exposure to the patient may cause secondary damage for the patients. Therefore, the degradation of the measured CT images may interferes with a clinical check in that blood vessel shapes o n the CT image are significantly affected by gaussian noise. In this study, we employed the spatio-temporal technique to analyze dynamic (brain perfusion) CT data to improve an image quality for successful clinical diagnosis. As a results, proposed technique could remove gaussian noise successfully, demonstrated a possibility of new image segmentation technique for CT angiography. Qualitative evaluation was conducted by skilled radiological technologists, indicated significant quality improvement of dynamic CT images. the proposed technique will be useful tools as a clinical application for brain perfusion CT examination.

  11. A spatio-temporal wavelet-chaos methodology for EEG-based diagnosis of Alzheimer's disease.

    Science.gov (United States)

    Adeli, Hojjat; Ghosh-Dastidar, Samanwoy; Dadmehr, Nahid

    2008-10-24

    A spatio-temporal wavelet-chaos methodology is presented for analysis of EEGs and their delta, theta, alpha, and beta sub-bands for discovering potential markers of abnormality in Alzheimer's disease (AD). The non-linear dynamics of the EEG and EEG sub-bands are quantified in the form of the correlation dimension (CD), representing system complexity, and the largest Lyapunov exponent (LLE), representing system chaoticity. The methodology is applied to two groups of EEGs: healthy subjects and AD patients. The eyes open and eyes closed conditions are investigated to evaluate the effect of visual input and attention. EEGs from different loci in the brain are investigated to discover areas of the brain responsible for or affected by changes in CD and LLE. It is found that the wavelet-chaos methodology and the sub-band analysis developed in this research accurately characterizes the non-linear dynamics of non-stationary EEG-like signals with respect to the EEG complexity and chaoticity. It is concluded that changes in the brain dynamics are not spread out equally across the spectrum of the EEG and over the entire brain, but are localized to certain frequency bands and electrode loci. New potential markers of abnormality were discovered in this research for both eyes open and closed conditions.

  12. Predicting grain yield in rice using multi-temporal vegetation indices from UAV-based multispectral and digital imagery

    Science.gov (United States)

    Zhou, X.; Zheng, H. B.; Xu, X. Q.; He, J. Y.; Ge, X. K.; Yao, X.; Cheng, T.; Zhu, Y.; Cao, W. X.; Tian, Y. C.

    2017-08-01

    Timely and non-destructive assessment of crop yield is an essential part of agricultural remote sensing (RS). The development of unmanned aerial vehicles (UAVs) has provided a novel approach for RS, and makes it possible to acquire high spatio-temporal resolution imagery on a regional scale. In this study, the rice grain yield was predicted with single stage vegetation indices (VIs) and multi-temporal VIs derived from the multispectral (MS) and digital images. The results showed that the booting stage was identified as the optimal stage for grain yield prediction with VIs at a single stage for both digital image and MS image. And corresponding optimal color index was VARI with R2 value of 0.71 (Log relationship). While the optimal vegetation index NDVI[800,720] based on MS images showed a linear relationship with the grain yield and gained a higher R2 value (0.75) than color index did. The multi-temporal VIs showed a higher correlation with grain yield than the single stage VIs did. And the VIs at two random growth stage with the multiple linear regression function [MLR(VI)] performed best. The highest correlation coefficient were 0.76 with MLR(NDVI[800,720]) at the booting and heading stages (for the MS image) and 0.73 with MLR(VARI) at the jointing and booting stages (for the digital image). In addition, the VIs that showed a high correlation with LAI performed well for yield prediction, and the VIs composed of red edge band (720 nm) and near infrared band (800 nm) were found to be more effective in predicting yield and LAI at high level. In conclusion, this study has demonstrated that both MS and digital sensors mounted on the UAV are reliable platforms for rice growth and grain yield estimation, and determined the best period and optimal VIs for rice grain yield prediction.

  13. Mining Temporal Protein Complex Based on the Dynamic PIN Weighted with Connected Affinity and Gene Co-Expression.

    Directory of Open Access Journals (Sweden)

    Xianjun Shen

    Full Text Available The identification of temporal protein complexes would make great contribution to our knowledge of the dynamic organization characteristics in protein interaction networks (PINs. Recent studies have focused on integrating gene expression data into static PIN to construct dynamic PIN which reveals the dynamic evolutionary procedure of protein interactions, but they fail in practice for recognizing the active time points of proteins with low or high expression levels. We construct a Time-Evolving PIN (TEPIN with a novel method called Deviation Degree, which is designed to identify the active time points of proteins based on the deviation degree of their own expression values. Owing to the differences between protein interactions, moreover, we weight TEPIN with connected affinity and gene co-expression to quantify the degree of these interactions. To validate the efficiencies of our methods, ClusterONE, CAMSE and MCL algorithms are applied on the TEPIN, DPIN (a dynamic PIN constructed with state-of-the-art three-sigma method and SPIN (the original static PIN to detect temporal protein complexes. Each algorithm on our TEPIN outperforms that on other networks in terms of match degree, sensitivity, specificity, F-measure and function enrichment etc. In conclusion, our Deviation Degree method successfully eliminates the disadvantages which exist in the previous state-of-the-art dynamic PIN construction methods. Moreover, the biological nature of protein interactions can be well described in our weighted network. Weighted TEPIN is a useful approach for detecting temporal protein complexes and revealing the dynamic protein assembly process for cellular organization.

  14. Temporal and spatial distribution characteristics in the natural plague foci of Chinese Mongolian gerbils based on spatial autocorrelation.

    Science.gov (United States)

    Du, Hai-Wen; Wang, Yong; Zhuang, Da-Fang; Jiang, Xiao-San

    2017-08-07

    The nest flea index of Meriones unguiculatus is a critical indicator for the prevention and control of plague, which can be used not only to detect the spatial and temporal distributions of Meriones unguiculatus, but also to reveal its cluster rule. This research detected the temporal and spatial distribution characteristics of the plague natural foci of Mongolian gerbils by body flea index from 2005 to 2014, in order to predict plague outbreaks. Global spatial autocorrelation was used to describe the entire spatial distribution pattern of the body flea index in the natural plague foci of typical Chinese Mongolian gerbils. Cluster and outlier analysis and hot spot analysis were also used to detect the intensity of clusters based on geographic information system methods. The quantity of M. unguiculatus nest fleas in the sentinel surveillance sites from 2005 to 2014 and host density data of the study area from 2005 to 2010 used in this study were provided by Chinese Center for Disease Control and Prevention. The epidemic focus regions of the Mongolian gerbils remain the same as the hot spot regions relating to the body flea index. High clustering areas possess a similar pattern as the distribution pattern of the body flea index indicating that the transmission risk of plague is relatively high. In terms of time series, the area of the epidemic focus gradually increased from 2005 to 2007, declined rapidly in 2008 and 2009, and then decreased slowly and began trending towards stability from 2009 to 2014. For the spatial change, the epidemic focus regions began moving northward from the southwest epidemic focus of the Mongolian gerbils from 2005 to 2007, and then moved from north to south in 2007 and 2008. The body flea index of Chinese gerbil foci reveals significant spatial and temporal aggregation characteristics through the employing of spatial autocorrelation. The diversity of temporary and spatial distribution is mainly affected by seasonal variation, the human

  15. Statistical forecasting for precipitation over West Africa based on spatio-temporal precipitation properties and tropical wave activity

    Science.gov (United States)

    Vogel, Peter; Klar, Manuel; Schlüter, Andreas; Knippertz, Peter; Fink, Andreas H.; Gneiting, Tilmann

    2017-04-01

    Precipitation forecasts for one up to several days are of high socioeconomic importance for agriculturally dominated societies in West Africa, regarding both the occurrence as well as the amount of precipitation. However, disappointingly forecasts based on numerical weather prediction models and even statistically postprocessed forecasts still do not outperform simple reference forecasts such as climatology or persistence. More elaborate statistical forecasts can hopefully lead to an improvement in the quality of precipitation forecasts above climatological or persistent ones. In this contribution, we concentrate on the potential of statistical forecasts to predict the occurrence of precipitation, while the prediction of the amount will be addressed in the future. Using increasingly sophisticated statistical models, we start with forecasts solely relying on the spatio-temporal information contained in precipitation observations. With the necessity of a full spatial coverage of precipitation observations in order to understand its spatio-temporal properties, we rely on Tropical Rainfall Measuring Mission (TRMM) observations and use accumulation periods of 1 to 5 days for the monsoon seasons from May to mid-October of the years 2007 to 2014. Especially for the full monsoon from the end of June to the end of September, the precipitation fields exhibit clear spatio-temporal information that is meteorologically interpretable and statistically meaningful. Using Markov models, we do in fact find an increased forecast quality for this period. While such forecasts already outperform persistent and climatological forecasts for the full monsoon, the forecast quality increases further and also covers the whole monsoon period from May to mid-October, when we add additional predictors. We find the activity of tropical waves such as Kelvin or African Easterly waves or the Madden-Julian Oscillation to be informative predictors and test for additional predictors closely linked to

  16. Mining Temporal Protein Complex Based on the Dynamic PIN Weighted with Connected Affinity and Gene Co-Expression.

    Science.gov (United States)

    Shen, Xianjun; Yi, Li; Jiang, Xingpeng; He, Tingting; Hu, Xiaohua; Yang, Jincai

    2016-01-01

    The identification of temporal protein complexes would make great contribution to our knowledge of the dynamic organization characteristics in protein interaction networks (PINs). Recent studies have focused on integrating gene expression data into static PIN to construct dynamic PIN which reveals the dynamic evolutionary procedure of protein interactions, but they fail in practice for recognizing the active time points of proteins with low or high expression levels. We construct a Time-Evolving PIN (TEPIN) with a novel method called Deviation Degree, which is designed to identify the active time points of proteins based on the deviation degree of their own expression values. Owing to the differences between protein interactions, moreover, we weight TEPIN with connected affinity and gene co-expression to quantify the degree of these interactions. To validate the efficiencies of our methods, ClusterONE, CAMSE and MCL algorithms are applied on the TEPIN, DPIN (a dynamic PIN constructed with state-of-the-art three-sigma method) and SPIN (the original static PIN) to detect temporal protein complexes. Each algorithm on our TEPIN outperforms that on other networks in terms of match degree, sensitivity, specificity, F-measure and function enrichment etc. In conclusion, our Deviation Degree method successfully eliminates the disadvantages which exist in the previous state-of-the-art dynamic PIN construction methods. Moreover, the biological nature of protein interactions can be well described in our weighted network. Weighted TEPIN is a useful approach for detecting temporal protein complexes and revealing the dynamic protein assembly process for cellular organization.

  17. The development of a performance assessment methodology for activity based intelligence: A study of spatial, temporal, and multimodal considerations

    Science.gov (United States)

    Lewis, Christian M.

    Activity Based Intelligence (ABI) is the derivation of information from a series of in- dividual actions, interactions, and transactions being recorded over a period of time. This usually occurs in Motion imagery and/or Full Motion Video. Due to the growth of unmanned aerial systems technology and the preponderance of mobile video devices, more interest has developed in analyzing people's actions and interactions in these video streams. Currently only visually subjective quality metrics exist for determining the utility of these data in detecting specific activities. One common misconception is that ABI boils down to a simple resolution problem; more pixels and higher frame rates are better. Increasing resolution simply provides more data, not necessary more informa- tion. As part of this research, an experiment was designed and performed to address this assumption. Nine sensors consisting of four modalities were place on top of the Chester F. Carlson Center for Imaging Science in order to record a group of participants executing a scripted set of activities. The multimodal characteristics include data from the visible, long-wave infrared, multispectral, and polarimetric regimes. The activities the participants were scripted to cover a wide range of spatial and temporal interactions (i.e. walking, jogging, and a group sporting event). As with any large data acquisition, only a subset of this data was analyzed for this research. Specifically, a walking object exchange scenario and simulated RPG. In order to analyze this data, several steps of preparation occurred. The data were spatially and temporally registered; the individual modalities were fused; a tracking algorithm was implemented, and an activity detection algorithm was applied. To develop a performance assessment for these activities a series of spatial and temporal degradations were performed. Upon completion of this work, the ground truth ABI dataset will be released to the community for further analysis.

  18. Conspecific sperm precedence in two species of tropical sea urchins.

    Science.gov (United States)

    Geyer, Laura B; Palumbi, Stephen R

    2005-01-01

    Conspecific sperm precedence occurs when females are exposed to sperm from males of multiple species, but preferentially use sperm of a conspecific. Conspecific sperm precedence and its mechanisms have been documented widely in terrestrial species, in which complex female behaviors or reproductive tract morphologies can allow many opportunities for female choice and sperm competition, however, the opportunity for conspecific sperm precedence in free spawning marine invertebrates has been largely ignored. Two sea urchin species, Echinometra oblonga and E. sp. C, have high levels of interspecific fertilization in no-choice lab crosses, but no natural hybrids have been found. We performed competitive fertilization assays to test for conspecific sperm precedence and found that eggs of both species showed a marked preference for conspecific sperm when fertilized with heterospecific sperm mixtures. Strong rejection of heterospecific sperm would not have been predicted from no-choice assays and helps explain the lack of natural hybrids. We also found significant variation in hybridization success among crosses. Conspecific sperm precedence in free spawning invertebrates shows that the simple surfaces of eggs and sperm provide ample opportunity for egg choice and sperm competition even in the absence of intricate behavior or complex reproductive morphologies.

  19. Facial Expression Recognition from Video Sequences Based on Spatial-Temporal Motion Local Binary Pattern and Gabor Multiorientation Fusion Histogram

    Directory of Open Access Journals (Sweden)

    Lei Zhao

    2017-01-01

    Full Text Available This paper proposes novel framework for facial expressions analysis using dynamic and static information in video sequences. First, based on incremental formulation, discriminative deformable face alignment method is adapted to locate facial points to correct in-plane head rotation and break up facial region from background. Then, spatial-temporal motion local binary pattern (LBP feature is extracted and integrated with Gabor multiorientation fusion histogram to give descriptors, which reflect static and dynamic texture information of facial expressions. Finally, a one-versus-one strategy based multiclass support vector machine (SVM classifier is applied to classify facial expressions. Experiments on Cohn-Kanade (CK + facial expression dataset illustrate that integrated framework outperforms methods using single descriptors. Compared with other state-of-the-art methods on CK+, MMI, and Oulu-CASIA VIS datasets, our proposed framework performs better.

  20. Skull base, orbits, temporal bone, and cranial nerves: anatomy on MR imaging.

    Science.gov (United States)

    Morani, Ajaykumar C; Ramani, Nisha S; Wesolowski, Jeffrey R

    2011-08-01

    Accurate delineation, diagnosis, and treatment planning of skull base lesions require knowledge of the complex anatomy of the skull base. Because the skull base cannot be directly evaluated, imaging is critical for the diagnosis and management of skull base diseases. Although computed tomography (CT) is excellent for outlining the bony detail, magnetic resonance (MR) imaging provides better soft tissue detail and is helpful for evaluating the adjacent meninges, brain parenchyma, and bone marrow of the skull base. Thus, CT and MR imaging are often used together for evaluating skull base lesions. This article focuses on the radiologic anatomy of the skull base pertinent to MR imaging evaluation. Copyright © 2011 Elsevier Inc. All rights reserved.

  1. Identification of drivers of (dis)liking based on dynamic sensory profiles: Comparison of Temporal Dominance of Sensations and Temporal Check-all-that-apply.

    Science.gov (United States)

    Ares, Gastón; Alcaire, Florencia; Antúnez, Lucía; Vidal, Leticia; Giménez, Ana; Castura, John C

    2017-02-01

    Temporal Dominance of Sensations (TDS) and Temporal Check-all-that-apply (TCATA) are two multi-attribute methods for dynamic sensory characterization. Previous research has shown that both methodologies provide complementary information. However, it remains an open question which of the two approaches better explains consumers' hedonic perception of products. In this context, the aim of the present work was to compare TDS and TCATA in terms of their ability to identify the influence of the dynamic sensory profile of food products on consumer overall liking scores. Two consumer studies were conducted using two different product categories (French bread and vanilla milk desserts). In each study, a between-subjects design was used to obtain dynamic sensory profiles using TDS and TCATA. After the dynamic sensory characterization tasks consumers rated their liking using a 9-point hedonic scale. Across the two studies, both methodologies provided similar information on the main drivers of liking and disliking, particularly when samples showed clear differences in liking. However, in one of the studies attribute applicability from TCATA provided additional insights on the influence of the dynamics of the sensory characteristics of products on consumers' liking. Results of the present work stress the complementarity between TCATA and TDS and highlight the potentiality of TCATA to provide a more detailed description of the dynamics of sensory perception during consumption. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. Enteropathy precedes type 1 diabetes in the BB rat.

    Science.gov (United States)

    Graham, S; Courtois, P; Malaisse, W J; Rozing, J; Scott, F W; Mowat, A Mc I

    2004-10-01

    There is increasing evidence implicating intestinal immune responses to dietary proteins in the pathogenesis of type 1 autoimmune diabetes (T1D). Here we investigated the association between intestinal pathology and dietary factors in T1D by examining the mucosal architecture in the BB rat model. BB control (BBc) and diabetes prone (BBdp) rats were fed either a diabetes retardant hydrolysed casein based diet or one of two cereal based diets that promote the development of diabetes. Intestinal architecture was assessed in the jejunum by microdissection, histology, and immunohistology, and by measuring peroxidase activity and brush border invertase levels. Enteropathy was present in BBdp rats soon after weaning, as assessed by increases in crypt length and in the proliferative activity of crypt epithelial cells in the jejunum, and this remained constant until 120 days of age. There was also a decrease in invertase activity, as well as increased numbers of intraepithelial lymphocytes, increased levels of mucosal peroxidase activity, and infiltration of the mucosa by CD4(+) T lymphocytes. Equivalent enteropathy was present at all times in BBdp rats and was not influenced by the nature of the diet or by thymectomy at three weeks at age, procedures which prevent the development of diabetes. Enteropathy is a consistent feature in the diabetes prone BB rat but it precedes the onset of insulitis and appears to be due to mechanisms distinct from those which cause diabetes. The beneficial effects of the diabetes retardant hydrolysed casein diet on diabetes are not due to an effect on intestinal architecture per se but mucosal damage may be necessary for the development of autoreactivity in the pancreas.

  3. Efficient Streaming Mass Spatio-Temporal Vehicle Data Access in Urban Sensor Networks Based on Apache Storm.

    Science.gov (United States)

    Zhou, Lianjie; Chen, Nengcheng; Chen, Zeqiang

    2017-04-10

    The efficient data access of streaming vehicle data is the foundation of analyzing, using and mining vehicle data in smart cities, which is an approach to understand traffic environments. However, the number of vehicles in urban cities has grown rapidly, reaching hundreds of thousands in number. Accessing the mass streaming data of vehicles is hard and takes a long time due to limited computation capability and backward modes. We propose an efficient streaming spatio-temporal data access based on Apache Storm (ESDAS) to achieve real-time streaming data access and data cleaning. As a popular streaming data processing tool, Apache Storm can be applied to streaming mass data access and real time data cleaning. By designing the Spout/bolt workflow of topology in ESDAS and by developing the speeding bolt and other bolts, Apache Storm can achieve the prospective aim. In our experiments, Taiyuan BeiDou bus location data is selected as the mass spatio-temporal data source. In the experiments, the data access results with different bolts are shown in map form, and the filtered buses' aggregation forms are different. In terms of performance evaluation, the consumption time in ESDAS for ten thousand records per second for a speeding bolt is approximately 300 milliseconds, and that for MongoDB is approximately 1300 milliseconds. The efficiency of ESDAS is approximately three times higher than that of MongoDB.

  4. Efficient Streaming Mass Spatio-Temporal Vehicle Data Access in Urban Sensor Networks Based on Apache Storm

    Directory of Open Access Journals (Sweden)

    Lianjie Zhou

    2017-04-01

    Full Text Available The efficient data access of streaming vehicle data is the foundation of analyzing, using and mining vehicle data in smart cities, which is an approach to understand traffic environments. However, the number of vehicles in urban cities has grown rapidly, reaching hundreds of thousands in number. Accessing the mass streaming data of vehicles is hard and takes a long time due to limited computation capability and backward modes. We propose an efficient streaming spatio-temporal data access based on Apache Storm (ESDAS to achieve real-time streaming data access and data cleaning. As a popular streaming data processing tool, Apache Storm can be applied to streaming mass data access and real time data cleaning. By designing the Spout/bolt workflow of topology in ESDAS and by developing the speeding bolt and other bolts, Apache Storm can achieve the prospective aim. In our experiments, Taiyuan BeiDou bus location data is selected as the mass spatio-temporal data source. In the experiments, the data access results with different bolts are shown in map form, and the filtered buses’ aggregation forms are different. In terms of performance evaluation, the consumption time in ESDAS for ten thousand records per second for a speeding bolt is approximately 300 milliseconds, and that for MongoDB is approximately 1300 milliseconds. The efficiency of ESDAS is approximately three times higher than that of MongoDB.

  5. Detection of whole-brain abnormalities in temporal lobe epilepsy using tensor-based morphometry with DARTEL

    Science.gov (United States)

    Li, Wenjing; He, Huiguang; Lu, Jingjing; Lv, Bin; Li, Meng; Jin, Zhengyu

    2009-10-01

    Tensor-based morphometry (TBM) is an automated technique for detecting the anatomical differences between populations by examining the gradients of the deformation fields used to nonlinearly warp MR images. The purpose of this study was to investigate the whole-brain volume changes between the patients with unilateral temporal lobe epilepsy (TLE) and the controls using TBM with DARTEL, which could achieve more accurate inter-subject registration of brain images. T1-weighted images were acquired from 21 left-TLE patients, 21 right-TLE patients and 21 healthy controls, which were matched in age and gender. The determinants of the gradient of deformation fields at voxel level were obtained to quantify the expansion or contraction for individual images relative to the template, and then logarithmical transformation was applied on it. A whole brain analysis was performed using general lineal model (GLM), and the multiple comparison was corrected by false discovery rate (FDR) with p<0.05. For left-TLE patients, significant volume reductions were found in hippocampus, cingulate gyrus, precentral gyrus, right temporal lobe and cerebellum. These results potentially support the utility of TBM with DARTEL to study the structural changes between groups.

  6. Spatio-Temporal Audio Enhancement Based on IAA Noise Covariance Matrix Estimates

    DEFF Research Database (Denmark)

    Nørholm, Sidsel Marie; Jensen, Jesper Rindom; Christensen, Mads Græsbøll

    2014-01-01

    A method for estimating the noise covariance matrix in a mul- tichannel setup is proposed. The method is based on the iter- ative adaptive approach (IAA), which only needs short seg- ments of data to estimate the covariance matrix. Therefore, the method can be used for fast varying signals...... to an amplitude and phase estimation (APES) based filter. For a fixed number of samples, the performance in terms of signal-to-noise ratio can be increased by using the IAA method, whereas if the filter size is fixed and the number of samples in the APES based filter is increased, the APES based filter performs...

  7. Effect of an Educational Intervention According to the PRECEDE Model to Promote Elderly Quality of Life

    Directory of Open Access Journals (Sweden)

    Parinaz Doshmangir

    2014-09-01

    Full Text Available Introduction: Increasing elderly population has increased attention to improve quality of life in elderly people. This paper aimed to study the effect of educational intervention based on the PRECEDE model to promote quality of life in elderly. Materials and Methods: In this experimental study, 80 elderly people were randomly divided into two intervention and control groups. Planning of educational program was performed according to the PRECEDE model. Before implementing the program, Quality of life questionnaire and a self-designed and standard questionnaire according to the PRECEDE Model were filled in both groups. Both groups were followed up one month after the intervention and previous questionnaires were filled again. Collected data was analyzed using paired T-test, independent sample T-test, one way ANOVA, Chi-square and ANCOVA by SPSS-21 software. Results: Through health promotion intervention, the mean score of quality of life increased from 76.77±13.23 to 82.87±12.25. There was a significant difference between the total score of quality of life of intervention and control groups (P=0.031. In addition, findings showed a significant difference in physical, mental, environmental and social dimensions before and after the intervention (P<0.05. Conclusion: Using the PRECEDE model could help to identify influential factors on quality of life in elderly and developing effective educational programs.

  8. Controlling Taenia solium in Nepal using the PRECEDE-PROCEED model.

    Science.gov (United States)

    Joshi, D D; Poudyal, P M; Jimba, M; Mishra, P N; Neave, L A; Maharjan, M

    2001-01-01

    Taenia solium is a predominant food-borne parasitic zoonosis (FBPZ) in Nepal. Using the PRECEDE framework, as defined by Green and Kreuter, we can identify the factors behind the high incidence of this disease. Armed with this information, we can define the actions necessary to control T. solium. In accordance with the first step of PRECEDE, social assessment, we set the goal of decreasing the potential for T. solium transmission in Nepal by the year 2003. This goal has yet to be endorsed by policy makers. However, an epidemiological assessment based on hospital data alone showed that T. solium is an endemic problem in urban Nepal that must be addressed. Based on behavioral and environmental assessments (Steps 1 and 2 of PRECEDE-PROCEED), we defined the following action objectives to be achieved by 2003: 1) Train meat producers and sellers to detect contaminated pork and avoid selling it, 2) Improve pig husbandry to limit the animals' access to human feces, 3) Construct hygienic model slaughterhouses. These improvements could control the meat-producing environment, thus limiting the potential for cross-carcass contamination and other hygiene deficiencies associated with the spread of T. solium. An educational and ecological assessment shows all predisposing, reinforcing and enabling factors are present in Nepal, consistent with PRECEDE requirements. While T. solium is clearly defined as a health problem according to PRECEDE, there remain significant hurdles to controlling it. These hurdles lie in administration and policy, where standardized law-enforcement and meat inspection practices are needed. Finally, the government of Nepal must assign high priority to T. solium control, as it is a preventable, yet prevalent disease.

  9. Multi-temporal UAV based data for mapping crop type and structure in smallholder dominated Tanzanian agricultural landscape

    Science.gov (United States)

    Nagol, J. R.; Chung, C.; Dempewolf, J.; Maurice, S.; Mbungu, W.; Tumbo, S.

    2015-12-01

    Timely mapping and monitoring of crops like Maize, an important food security crop in Tanzania, can facilitate timely response by government and non-government organizations to food shortage or surplus conditions. Small UAVs can play an important role in linking the spaceborne remote sensing data and ground based measurement to improve the calibration and validation of satellite based estimates of in-season crop metrics. In Tanzania most of the growing season is often obscured by clouds. UAV data, if collected within a stratified statistical sampling framework, can also be used to directly in lieu of spaceborne data to infer mid-season yield estimates at regional scales.Here we present an object based approach to estimate crop metrics like crop type, area, and height using multi-temporal UAV based imagery. The methods were tested at three 1km2 plots in Kilosa, Njombe, and Same districts in Tanzania. At these sites both ground based and UAV based data were collected on a monthly time-step during the year 2015 growing season. SenseFly eBee drone with RGB and NIR-R-G camera was used to collect data. Crop type classification accuracies of above 85% were easily achieved.

  10. A Phenology-based Approach for Rice Crop Mapping from Multi-temporal Sentinel-1A Data in Taiwan

    Science.gov (United States)

    Chen, C. F.; Chen, J. B.; Nguyen, S. T.; Chen, C. R.; Chiang, S. H.

    2016-12-01

    Rice is the most important food crop in Taiwan, accounting for approximately 5% (166,616 ha) of the total cultivated area. Besides its nutritional value, rice agriculture remains the primary source of livelihood for the majority of rural populations in the country. Rice monitoring is a crucial activity due to official initiatives to ensure the national food security. Because the size of rice fields in Taiwan is relatively small, rice monitoring is traditionally implemented through time-consuming and costly visual interpretation of aerial photos. The Sentinel-1A launched on 3 April 2014 provides the data that have sufficient spatial and temporal resolutions (i.e., 10 m resolution and 12-day revisit cycle) for monitoring small patches of rice fields in the country. This study aimed to develop a phenology-based approach to map rice-growing areas in Taiwan from multi-temporal descending Sentinel-1A VH and VV data. The data were processed for the second rice cropping season (July‒December) in 2015, consisting four main steps: (1) data pre-processing, including radiometric and geometric corrections, and speckle noise filtering of the VH and VV backscattering coefficient data, (2) normalization difference sigma-naught index (NDSI) calculation based on the sowing and heading periods obtained from the analysis of rice crop phenology in the region, (3) threshold-based rice classification using the expectation-maximization method, and (4) accuracy assessment of the mapping results. The mapping results compared with the ground reference data indicated that the overall accuracies and Kappa coefficients achieved for the VH data were 92.0% and 0.84, while the values for the VV data were 81.1% and 0.62, respectively. The mapping results further verified with the government's rice area statistics reaffirmed the consistency between these two datasets with the root mean square error (RMSE) less than 1%, in both cases. This study demonstrates the potential application of multi-temporal

  11. Preceding trauma in childhood hematogenous bone and joint infections.

    Science.gov (United States)

    Pääkkönen, Markus; Kallio, Markku J T; Lankinen, Petteri; Peltola, Heikki; Kallio, Pentti E

    2014-03-01

    Preceding trauma may play a role in the etiology and pathogenesis of hematogenous bone and joint infections. Among 345 children with an acute hematogenous bone and/or joint infection, 20% reported trauma during a 2-week period leading to infection. Blunt impact, bruises, or excoriations were commonly reported. The rate was similar to that in the general pediatric population obtained from the literature. In the study group, patients with and without trauma were similar in age, serum C-reactive protein and erythrocyte sedimentation rate, length of hospitalization, and late sequelae. Preceding minor trauma did not prove to be significant as an etiological or as a prognostic factor.

  12. Discovery of time-delayed gene regulatory networks based on temporal gene expression profiling

    Directory of Open Access Journals (Sweden)

    Guo Zheng

    2006-01-01

    Full Text Available Abstract Background It is one of the ultimate goals for modern biological research to fully elucidate the intricate interplays and the regulations of the molecular determinants that propel and characterize the progression of versatile life phenomena, to name a few, cell cycling, developmental biology, aging, and the progressive and recurrent pathogenesis of complex diseases. The vast amount of large-scale and genome-wide time-resolved data is becoming increasing available, which provides the golden opportunity to unravel the challenging reverse-engineering problem of time-delayed gene regulatory networks. Results In particular, this methodological paper aims to reconstruct regulatory networks from temporal gene expression data by using delayed correlations between genes, i.e., pairwise overlaps of expression levels shifted in time relative each other. We have thus developed a novel model-free computational toolbox termed TdGRN (Time-delayed Gene Regulatory Network to address the underlying regulations of genes that can span any unit(s of time intervals. This bioinformatics toolbox has provided a unified approach to uncovering time trends of gene regulations through decision analysis of the newly designed time-delayed gene expression matrix. We have applied the proposed method to yeast cell cycling and human HeLa cell cycling and have discovered most of the underlying time-delayed regulations that are supported by multiple lines of experimental evidence and that are remarkably consistent with the current knowledge on phase characteristics for the cell cyclings. Conclusion We established a usable and powerful model-free approach to dissecting high-order dynamic trends of gene-gene interactions. We have carefully validated the proposed algorithm by applying it to two publicly available cell cycling datasets. In addition to uncovering the time trends of gene regulations for cell cycling, this unified approach can also be used to study the complex

  13. Increased cerebral oxygenation precedes generalized tonic clonic seizures.

    Science.gov (United States)

    Moseley, Brian D; Britton, Jeffrey W; So, Elson

    2014-11-01

    Based on previous fMRI and SPECT studies, it has been suggested seizures may be preceded by increased cerebral blood flow. Recently, we demonstrated transcutaneous regional cerebral oxygen saturation (rSO2) sensors are feasible for use in patients undergoing video EEG monitoring. We reanalyzed our data to determine if seizures were consistently marked by increased cerebral oxygenation. Patients with histories of generalized tonic clonic seizures (GTCS) were recruited into our study. All subjects were evaluated with continuous 30-channel scalp EEG and 2 rSO2 sensors placed on each side of the forehead. We calculated the mean rSO2 value for the 1h epochs in the non-ictal (2h prior to seizure onset) and pre-ictal (1h prior to onset) periods. Seven primary/secondarily GTCS from 5 patients were captured. The mean rSO2 value in the non-ictal period was 75.6 ± 5.7%. This increased to 76.0 ± 6% in the pre-ictal period (p=0.032). Four of the 7GTCS (57.1%) were marked by ≥ 3 sequential rSO2 values in the pre-ictal period that were ≥ 3 SDs greater than the mean non-ictal rSO2 value. Three GTCS (42.9%) were marked by sustained cerebral hyperemia for ≥ 15 consecutive readings. Our results suggest increased cerebral blood flow could be non-invasively used to predict seizure occurrence. Copyright © 2014 Elsevier B.V. All rights reserved.

  14. A model-based analysis of chemical and temporal patterns of cuticular hydrocarbons in male Drosophila melanogaster.

    Directory of Open Access Journals (Sweden)

    Clement Kent

    Full Text Available Drosophila Cuticular Hydrocarbons (CH influence courtship behaviour, mating, aggregation, oviposition, and resistance to desiccation. We measured levels of 24 different CH compounds of individual male D. melanogaster hourly under a variety of environmental (LD/DD conditions. Using a model-based analysis of CH variation, we developed an improved normalization method for CH data, and show that CH compounds have reproducible cyclic within-day temporal patterns of expression which differ between LD and DD conditions. Multivariate clustering of expression patterns identified 5 clusters of co-expressed compounds with common chemical characteristics. Turnover rate estimates suggest CH production may be a significant metabolic cost. Male cuticular hydrocarbon expression is a dynamic trait influenced by light and time of day; since abundant hydrocarbons affect male sexual behavior, males may present different pheromonal profiles at different times and under different conditions.

  15. Sensory neural pathways revisited to unravel the temporal dynamics of the Simon effect: A model-based cognitive neuroscience approach.

    Science.gov (United States)

    Salzer, Yael; de Hollander, Gilles; Forstmann, Birte U

    2017-06-01

    The Simon task is one of the most prominent interference tasks and has been extensively studied in experimental psychology and cognitive neuroscience. Despite years of research, the underlying mechanism driving the phenomenon and its temporal dynamics are still disputed. Within the framework of the review, we adopt a model-based cognitive neuroscience approach. We first go over key findings in the literature of the Simon task, discuss competing qualitative cognitive theories and the difficulty of testing them empirically. We then introduce sequential sampling models, a particular class of mathematical cognitive process models. Finally, we argue that the brain architecture accountable for the processing of spatial ('where') and non-spatial ('what') information, could constrain these models. We conclude that there is a clear need to bridge neural and behavioral measures, and that mathematical cognitive models may facilitate the construction of this bridge and work towards revealing the underlying mechanisms of the Simon effect. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. An advanced temporal credential-based security scheme with mutual authentication and key agreement for wireless sensor networks.

    Science.gov (United States)

    Li, Chun-Ta; Weng, Chi-Yao; Lee, Cheng-Chi

    2013-07-24

    Wireless sensor networks (WSNs) can be quickly and randomly deployed in any harsh and unattended environment and only authorized users are allowed to access reliable sensor nodes in WSNs with the aid of gateways (GWNs). Secure authentication models among the users, the sensor nodes and GWN are important research issues for ensuring communication security and data privacy in WSNs. In 2013, Xue et al. proposed a temporal-credential-based mutual authentication and key agreement scheme for WSNs. However, in this paper, we point out that Xue et al.'s scheme cannot resist stolen-verifier, insider, off-line password guessing, smart card lost problem and many logged-in users' attacks and these security weaknesses make the scheme inapplicable to practical WSN applications. To tackle these problems, we suggest a simple countermeasure to prevent proposed attacks while the other merits of Xue et al.'s authentication scheme are left unchanged.

  17. An Advanced Temporal Credential-Based Security Scheme with Mutual Authentication and Key Agreement for Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Chun-Ta Li

    2013-07-01

    Full Text Available Wireless sensor networks (WSNs can be quickly and randomly deployed in any harsh and unattended environment and only authorized users are allowed to access reliable sensor nodes in WSNs with the aid of gateways (GWNs. Secure authentication models among the users, the sensor nodes and GWN are important research issues for ensuring communication security and data privacy in WSNs. In 2013, Xue et al. proposed a temporal-credential-based mutual authentication and key agreement scheme for WSNs. However, in this paper, we point out that Xue et al.’s scheme cannot resist stolen-verifier, insider, off-line password guessing, smart card lost problem and many logged-in users’ attacks and these security weaknesses make the scheme inapplicable to practical WSN applications. To tackle these problems, we suggest a simple countermeasure to prevent proposed attacks while the other merits of Xue et al.’s authentication scheme are left unchanged.

  18. Cytology and human papillomavirus co-test results preceding incident high-grade cervical intraepithelial neoplasia.

    Directory of Open Access Journals (Sweden)

    Ina U Park

    Full Text Available High-risk HPV (hrHPV and cytology co-testing is utilized for primary cervical cancer screening and for enhanced follow-up of women who are hrHPV-positive, cytology negative. However, data are lacking on the utility of this method to detect pre-cancer or cancer in community-based clinical practice. This study describes cytology and hrHPV results preceding high-grade cervical intraepithelial neoplasia, adenocarcinoma in situ, or cervical cancer (i.e., CIN2+ in an integrated health system employing routine co-testing among women aged 30 years and older.We conducted a cross-sectional analysis of adult female members of Kaiser Permanente Northern California (KPNC with incident CIN2+ between July 2008 and June 2009. The primary outcome was the proportions of cytologic diagnoses and hrHPV co-test results preceding a diagnosis of CIN2+. Cervical cytology and hrHPV testing results were abstracted from electronic medical records.Of 1283 CIN2+ cases among adult women, 880 (68.5% were among women aged 30 years and older and 145/880 (16.5%, 95% CI 14.1-19.1 had only normal cytology during the 12 months prior to diagnosis. Furthermore, 133/880 (15.1%, 95% 12.9-17.7 were preceded by only normal cytology and persistent hrHPV infection (at least 2 positive hrHPV tests during the 6-36 months preceding CIN2+ diagnosis.Incident CIN2+ is frequently preceded by normal cytology and persistent hrHPV infection among women aged 30 years and older; screening strategies that employ HPV testing and cytology may improve the detection of CIN2+ compared with cytology alone.

  19. Predicting commuter flows in spatial networks using a radiation model based on temporal ranges

    Science.gov (United States)

    Ren, Yihui; Ercsey-Ravasz, Mária; Wang, Pu; González, Marta C.; Toroczkai, Zoltán

    2014-11-01

    Understanding network flows such as commuter traffic in large transportation networks is an ongoing challenge due to the complex nature of the transportation infrastructure and human mobility. Here we show a first-principles based method for traffic prediction using a cost-based generalization of the radiation model for human mobility, coupled with a cost-minimizing algorithm for efficient distribution of the mobility fluxes through the network. Using US census and highway traffic data, we show that traffic can efficiently and accurately be computed from a range-limited, network betweenness type calculation. The model based on travel time costs captures the log-normal distribution of the traffic and attains a high Pearson correlation coefficient (0.75) when compared with real traffic. Because of its principled nature, this method can inform many applications related to human mobility driven flows in spatial networks, ranging from transportation, through urban planning to mitigation of the effects of catastrophic events.

  20. The South African constitutional court's use of foreign precedent in ...

    African Journals Online (AJOL)

    ... Court or whether it is a characteristic of a court which is confident enough that its independence will remain intact in spite of its looking elsewhere for answers. KEYWORDS: transjudicialism; foreign precedent, comparative judicialism, stare decisis; foreign case law; comparative constitutionalism; Constitutional Court.

  1. Cross-frequency interactions in the precedence effect.

    Science.gov (United States)

    Shinn-Cunningham, B G; Zurek, P M; Durlach, N I; Clifton, R K

    1995-07-01

    This paper concerns the extent to which the precedence effect is observed when leading and lagging sounds occupy different spectral regions. Subjects, listening under headphones, were asked to match the intracranial lateral position of an acoustic pointer to that of a test stimulus composed of two binaural noise bursts with asynchronous onsets, parametrically varied frequency content, and different interaural delays. The precedence effect was measured by the degree to which the interaural delay of the matching pointer was independent of the interaural delay of the lagging noise burst in the test stimulus. The results, like those of Blauert and Divenyi [Acustica 66, 267-274 (1988)], show an asymmetric frequency effect in which the lateralization influence of a lagging high-frequency burst is almost completely suppressed by a leading low-frequency burst, whereas a lagging low-frequency burst is weighted equally with a leading high-frequency burst. This asymmetry is shown to be the result of an inherent low-frequency dominance that is seen even with simultaneous bursts. When this dominance is removed (by attenuating the low-frequency burst) the precedence effect operates with roughly equal strength both upward and downward in frequency. Within the scope of the current study (with lateralization achieved through the use of interaural time differences alone, stimuli from only two frequency bands, and only three subjects performing in all experiments), these results suggest that the precedence effect arises from a fairly central processing stage in which information is combined across frequency.

  2. Independence Pending: Teacher Behaviors Preceding Learner Problem Solving

    Science.gov (United States)

    Roesler, Rebecca A.

    2017-01-01

    The purposes of the present study were to identify the teacher behaviors that preceded learners' active participation in solving musical and technical problems and describe learners' roles in the problem-solving process. I applied an original model of problem solving to describe the behaviors of teachers and students in 161 rehearsal frames…

  3. The Role of Sexual Precedence in Verbal Sexual Coercion

    Science.gov (United States)

    Livingston, Jennifer A.; Buddie, Amy M.; Testa, Maria; VanZile-Tamsen, Carol

    2004-01-01

    Experiences of verbal sexual coercion are common and have potential for negative consequences, yet are not well understood. This study used qualitative and descriptive statistics to examine verbal sexual coercion experiences among a community sample of 114 women and explored the role of sexual precedence in these experiences. Analyses revealed…

  4. Flow-based dissimilarity measures for reservoir models : a spatial-temporal tensor approach

    NARCIS (Netherlands)

    Insuasty, Edwin; van den Hof, P.M.J.; Weiland, Siep; Jansen, J.D.

    2017-01-01

    In reservoir engineering, it is attractive to characterize the difference between reservoir models in metrics that relate to the economic performance of the reservoir as well as to the underlying geological structure. In this paper, we develop a dissimilarity measure that is based on reservoir

  5. Blood velocity estimation using spatio-temporal encoding based on frequency division approach

    DEFF Research Database (Denmark)

    Gran, Fredrik; Nikolov, Svetoslav; Jensen, Jørgen Arendt

    2005-01-01

    In this paper a feasibility study of using a spatial encoding technique based on frequency division for blood flow estimation is presented. The spatial encoding is carried out by dividing the available bandwidth of the transducer into a number of narrow frequency bands with approximately disjoint...

  6. Temporal Photon Differentials

    DEFF Research Database (Denmark)

    Schjøth, Lars; Frisvad, Jeppe Revall; Erleben, Kenny

    2010-01-01

    , constituting a temporal smoothing of rapidly changing illumination. In global illumination temporal smoothing can be achieved with distribution ray tracing (Cook et al., 1984). Unfortunately, this, and resembling methods, requires a high temporal resolution as samples has to be drawn from in-between frames. We...... present a novel method which is able to produce high quality temporal smoothing for indirect illumination without using in-between frames. Our method is based on ray differentials (Igehy, 1999) as it has been extended in (Sporring et al., 2009). Light rays are traced as bundles creating footprints, which......The finite frame rate also used in computer animated films is cause of adverse temporal aliasing effects. Most noticeable of these is a stroboscopic effect that is seen as intermittent movement of fast moving illumination. This effect can be mitigated using non-zero shutter times, effectively...

  7. Oral hygiene behaviors and caries experience in Northwest PRECEDENT patients.

    Science.gov (United States)

    Rothen, Marilynn; Cunha-Cruz, Joana; Zhou, Lingmei; Mancl, Lloyd; Jones, Jackie S; Berg, Joel

    2014-12-01

    To investigate the association between oral hygiene behaviors (toothbrushing, water rinsing after brushing, interproximal cleaning, and adjunctive use of fluoride products) and recent caries (past 24 months) in a random sample of patients in Northwest PRECEDENT practices. Practitioner-members of Northwest PRECEDENT, a dental practice-based research network, conducted a longitudinal study on caries risk assessment. At baseline, patients completed a questionnaire on oral self-care, snacking, health, and socio-demographics. A dental examination recorded readily visible heavy plaque and decayed, missing, and filled teeth; chart review captured new caries and treatments in the previous 24 months. Bivariate and multiple generalized estimating equations (GEE) log-linear regression models stratified by age-groups were used to relate oral hygiene behaviors to the primary outcome of mean dental caries in the past 24 months on data from 1400 patients in 63 practices. The primary exposure of interest was fluoride toothbrushing frequency. Fluoride toothbrushing once per day or twice or more per day by patients 9-17 was significantly associated with a 50% lower mean caries rate compared with fluoride toothbrushing less than once per day, after adjustment for covariates [rate ratios (RR) = 0.5; 95% confidence intervals (CI) = 0.3-0.8]. After adjustment, for patients 18-64, fluoride toothbrushing two or more times per day was significantly associated with a 40% lower recent mean caries rate (RR = 0.6; 95% CI = 0.4-0.9); in patients 65+, twice a day or more fluoride toothbrushing was not associated with lower caries rates (RR = 1.1; 95% CI = 0.7-1.8). Of the other oral hygiene variables, after adjustment, patients 18-64 who rinsed with water after brushing had a 40% lower mean caries rate compared with no rinsing (RR = 0.6; 95% CI = 0.4-0.9) and the presence of readily visible heavy plaque was significantly associated with an increase in the mean caries rate for

  8. Oral Hygiene Behaviors and Caries Experience in Northwest PRECEDENT Patients

    Science.gov (United States)

    Rothen, Marilynn; Cunha-Cruz, Joana; Zhou, Lingmei; Mancl, Lloyd; Jones, Jackie S.; Berg, Joel

    2014-01-01

    Objectives To investigate the association between oral hygiene behaviors (toothbrushing, water rinsing after brushing, interproximal cleaning, and adjunctive use of fluoride products) and recent caries (past 24 months) in a random sample of patients in Northwest PRECEDENT practices. Methods Practitioner-members of Northwest PRECEDENT dental Practice-based Research Network (PBRN) conducted a longitudinal study on caries risk assessment. At baseline patients completed a questionnaire on oral self-care, snacking, health, and socio-demographics. A dental exam recorded readily-visible heavy plaque and DMFT; chart review captured new caries and treatments in the previous 24 months. Bivariate and multiple GEE log-linear regression models stratified by age groups were used to relate oral hygiene behaviors to the primary outcome of mean dental caries in the past 24 months on data from 1400 patients in 63 practices. The primary exposure of interest was fluoride toothbrushing frequency. Results Fluoride toothbrushing once per day or more by patients 9-17 was significantly associated with a 50% lower mean caries rate compared to fluoride toothbrushing less than once per day, after adjustment for age, gender, race, education, income, between-meal carbohydrate snacks, sugar-added beverages, alcohol consumption, smoking, BMI, exercise, stimulated salivary pH, number of teeth, and all other oral hygiene behaviors captured [Rate Ratio (RR)=0.5; 95% confidence interval (CI)=0.3-0.8]. After adjustment, for patients 18-64 fluoride toothbrushing two or more times per day was significantly associated with a 40% lower recent mean caries rate (RR=0.6; 95%CI=0.4-0.9); in patients 65+, twice a day or more fluoride toothbrushing was not associated with lower caries rates (RR=1.1; 95%CI=0.7-1.8). Of the other oral hygiene variables, after adjustment, patients 18-64 who rinsed with water after brushing had a 40% lower mean caries rate compared to no rinsing (RR=0.6; 95%CI=0.4-0.9) and the

  9. Spatial and Temporal Wind Power Forecasting by Case-Based Reasoning Using Big-Data

    Directory of Open Access Journals (Sweden)

    Fabrizio De Caro

    2017-02-01

    Full Text Available The massive penetration of wind generators in electrical power systems asks for effective wind power forecasting tools, which should be high reliable, in order to mitigate the effects of the uncertain generation profiles, and fast enough to enhance power system operation. To address these two conflicting objectives, this paper advocates the role of knowledge discovery from big-data, by proposing the integration of adaptive Case Based Reasoning models, and cardinality reduction techniques based on Partial Least Squares Regression, and Principal Component Analysis. The main idea is to learn from a large database of historical climatic observations, how to solve the windforecasting problem, avoiding complex and time-consuming computations. To assess the benefits derived by the application of the proposed methodology in complex application scenarios, the experimental results obtained in a real case study will be presented and discussed.

  10. The role of temporal resolution in modulation-based speech segregation

    DEFF Research Database (Denmark)

    May, Tobias; Bentsen, Thomas; Dau, Torsten

    2015-01-01

    This study is concerned with the challenge of automatically segregating a target speech signal from interfering background noise. A computational speech segregation system is presented which exploits logarithmically-scaled amplitude modulation spectrogram (AMS) features to distinguish between spe...... with which the segregation system can manipulate individual T-F units. To clarify the consequences of this trade-off on modulation-based speech segregation performance, the influence of the window duration was systematically investigated...

  11. Neural correlates of temporal credit assignment in the parietal lobe.

    Directory of Open Access Journals (Sweden)

    Timothy M Gersch

    Full Text Available Empirical studies of decision making have typically assumed that value learning is governed by time, such that a reward prediction error arising at a specific time triggers temporally-discounted learning for all preceding actions. However, in natural behavior, goals must be acquired through multiple actions, and each action can have different significance for the final outcome. As is recognized in computational research, carrying out multi-step actions requires the use of credit assignment mechanisms that focus learning on specific steps, but little is known about the neural correlates of these mechanisms. To investigate this question we recorded neurons in the monkey lateral intraparietal area (LIP during a serial decision task where two consecutive eye movement decisions led to a final reward. The underlying decision trees were structured such that the two decisions had different relationships with the final reward, and the optimal strategy was to learn based on the final reward at one of the steps (the "F" step but ignore changes in this reward at the remaining step (the "I" step. In two distinct contexts, the F step was either the first or the second in the sequence, controlling for effects of temporal discounting. We show that LIP neurons had the strongest value learning and strongest post-decision responses during the transition after the F step regardless of the serial position of this step. Thus, the neurons encode correlates of temporal credit assignment mechanisms that allocate learning to specific steps independently of temporal discounting.

  12. Does Temporal Integration Occur for Unrecognizable Words in Visual Crowding?

    Directory of Open Access Journals (Sweden)

    Jifan Zhou

    Full Text Available Visual crowding-the inability to see an object when it is surrounded by flankers in the periphery-does not block semantic activation: unrecognizable words due to visual crowding still generated robust semantic priming in subsequent lexical decision tasks. Based on the previous finding, the current study further explored whether unrecognizable crowded words can be temporally integrated into a phrase. By showing one word at a time, we presented Chinese four-word idioms with either a congruent or incongruent ending word in order to examine whether the three preceding crowded words can be temporally integrated to form a semantic context so as to affect the processing of the ending word. Results from both behavioral (Experiment 1 and Event-Related Potential (Experiment 2 and 3 measures showed congruency effect in only the non-crowded condition, which does not support the existence of unconscious multi-word integration. Aside from four-word idioms, we also found that two-word (modifier + adjective combination integration-the simplest kind of temporal semantic integration-did not occur in visual crowding (Experiment 4. Our findings suggest that integration of temporally separated words might require conscious awareness, at least under the timing conditions tested in the current study.

  13. The recurrent event process of a success preceded by a failure and its application

    Directory of Open Access Journals (Sweden)

    C. D. Lai

    1997-01-01

    Full Text Available We describe a simple discrete time renewal process of an event where a success is preceded by a failure. Its properties, especially the distributions of the counting and the interval processes, are investigated. We also propose an application to statistical process control based on the waiting time between two adjacent events. It is shown that the average number inspected under the new control scheme is larger than with the so called CCC control chart.

  14. Change Detection Research Based on Multi-Temporal and Multi-Polarization PALSAR Data

    Science.gov (United States)

    Gu, Xinzhi; Chen, Erxue

    2016-08-01

    Synthetic aperture radar (SAR) image change detection is an important technique in the remote sensing area. Long time-series of high quality SAR data can be acquired from spaceborne and airborne SAR systems. In this paper, a logarithmic ratio technique is proposed for two-date multichannel SAR images using ALOS-2PALSAR(L-band SAR). The ratio image can relieve the influence of the speckle noise and improve the discrimination between changed and unchanged areas. Based on the ALOS-2PALSAR data, the paper presents a reliable way to monitor the forest change using Fisher transform and mathematical statistics and get the changed area.

  15. Evolving spatio-temporal data machines based on the NeuCube neuromorphic framework: Design methodology and selected applications.

    Science.gov (United States)

    Kasabov, Nikola; Scott, Nathan Matthew; Tu, Enmei; Marks, Stefan; Sengupta, Neelava; Capecci, Elisa; Othman, Muhaini; Doborjeh, Maryam Gholami; Murli, Norhanifah; Hartono, Reggio; Espinosa-Ramos, Josafath Israel; Zhou, Lei; Alvi, Fahad Bashir; Wang, Grace; Taylor, Denise; Feigin, Valery; Gulyaev, Sergei; Mahmoud, Mahmoud; Hou, Zeng-Guang; Yang, Jie

    2016-06-01

    The paper describes a new type of evolving connectionist systems (ECOS) called evolving spatio-temporal data machines based on neuromorphic, brain-like information processing principles (eSTDM). These are multi-modular computer systems designed to deal with large and fast spatio/spectro temporal data using spiking neural networks (SNN) as major processing modules. ECOS and eSTDM in particular can learn incrementally from data streams, can include 'on the fly' new input variables, new output class labels or regression outputs, can continuously adapt their structure and functionality, can be visualised and interpreted for new knowledge discovery and for a better understanding of the data and the processes that generated it. eSTDM can be used for early event prediction due to the ability of the SNN to spike early, before whole input vectors (they were trained on) are presented. A framework for building eSTDM called NeuCube along with a design methodology for building eSTDM using this is presented. The implementation of this framework in MATLAB, Java, and PyNN (Python) is presented. The latter facilitates the use of neuromorphic hardware platforms to run the eSTDM. Selected examples are given of eSTDM for pattern recognition and early event prediction on EEG data, fMRI data, multisensory seismic data, ecological data, climate data, audio-visual data. Future directions are discussed, including extension of the NeuCube framework for building neurogenetic eSTDM and also new applications of eSTDM. Copyright © 2015 Elsevier Ltd. All rights reserved.

  16. Relationship between neuronal network architecture and naming performance in temporal lobe epilepsy: A connectome based approach using machine learning.

    Science.gov (United States)

    Munsell, B C; Wu, G; Fridriksson, J; Thayer, K; Mofrad, N; Desisto, N; Shen, D; Bonilha, L

    2017-09-09

    Impaired confrontation naming is a common symptom of temporal lobe epilepsy (TLE). The neurobiological mechanisms underlying this impairment are poorly understood but may indicate a structural disorganization of broadly distributed neuronal networks that support naming ability. Importantly, naming is frequently impaired in other neurological disorders and by contrasting the neuronal structures supporting naming in TLE with other diseases, it will become possible to elucidate the common systems supporting naming. We aimed to evaluate the neuronal networks that support naming in TLE by using a machine learning algorithm intended to predict naming performance in subjects with medication refractory TLE using only the structural brain connectome reconstructed from diffusion tensor imaging. A connectome-based prediction framework was developed using network properties from anatomically defined brain regions across the entire brain, which were used in a multi-task machine learning algorithm followed by support vector regression. Nodal eigenvector centrality, a measure of regional network integration, predicted approximately 60% of the variance in naming. The nodes with the highest regression weight were bilaterally distributed among perilimbic sub-networks involving mainly the medial and lateral temporal lobe regions. In the context of emerging evidence regarding the role of large structural networks that support language processing, our results suggest intact naming relies on the integration of sub-networks, as opposed to being dependent on isolated brain areas. In the case of TLE, these sub-networks may be disproportionately indicative naming processes that are dependent semantic integration from memory and lexical retrieval, as opposed to multi-modal perception or motor speech production. Copyright © 2017. Published by Elsevier Inc.

  17. Multimedia human brain database system for surgical candidacy determination in temporal lobe epilepsy with content-based image retrieval

    Science.gov (United States)

    Siadat, Mohammad-Reza; Soltanian-Zadeh, Hamid; Fotouhi, Farshad A.; Elisevich, Kost

    2003-01-01

    This paper presents the development of a human brain multimedia database for surgical candidacy determination in temporal lobe epilepsy. The focus of the paper is on content-based image management, navigation and retrieval. Several medical image-processing methods including our newly developed segmentation method are utilized for information extraction/correlation and indexing. The input data includes T1-, T2-Weighted MRI and FLAIR MRI and ictal and interictal SPECT modalities with associated clinical data and EEG data analysis. The database can answer queries regarding issues such as the correlation between the attribute X of the entity Y and the outcome of a temporal lobe epilepsy surgery. The entity Y can be a brain anatomical structure such as the hippocampus. The attribute X can be either a functionality feature of the anatomical structure Y, calculated with SPECT modalities, such as signal average, or a volumetric/morphological feature of the entity Y such as volume or average curvature. The outcome of the surgery can be any surgery assessment such as memory quotient. A determination is made regarding surgical candidacy by analysis of both textual and image data. The current database system suggests a surgical determination for the cases with relatively small hippocampus and high signal intensity average on FLAIR images within the hippocampus. This indication pretty much fits with the surgeons" expectations/observations. Moreover, as the database gets more populated with patient profiles and individual surgical outcomes, using data mining methods one may discover partially invisible correlations between the contents of different modalities of data and the outcome of the surgery.

  18. An Image-Based Approach for the Co-Registration of Multi-Temporal UAV Image Datasets

    Directory of Open Access Journals (Sweden)

    Irene Aicardi

    2016-09-01

    Full Text Available During the past years, UAVs (Unmanned Aerial Vehicles became very popular as low-cost image acquisition platforms since they allow for high resolution and repetitive flights in a flexible way. One application is to monitor dynamic scenes. However, the fully automatic co-registration of the acquired multi-temporal data still remains an open issue. Most UAVs are not able to provide accurate direct image georeferencing and the co-registration process is mostly performed with the manual introduction of ground control points (GCPs, which is time consuming, costly and sometimes not possible at all. A new technique to automate the co-registration of multi-temporal high resolution image blocks without the use of GCPs is investigated in this paper. The image orientation is initially performed on a reference epoch and the registration of the following datasets is achieved including some anchor images from the reference data. The interior and exterior orientation parameters of the anchor images are then fixed in order to constrain the Bundle Block Adjustment of the slave epoch to be aligned with the reference one. The study involved the use of two different datasets acquired over a construction site and a post-earthquake damaged area. Different tests have been performed to assess the registration procedure using both a manual and an automatic approach for the selection of anchor images. The tests have shown that the procedure provides results comparable to the traditional GCP-based strategy and both the manual and automatic selection of the anchor images can provide reliable results.

  19. Knowledge engineering for temporal dependency networks as operations procedures. [in space communication

    Science.gov (United States)

    Fayyad, Kristina E.; Hill, Randall W., Jr.; Wyatt, E. J.

    1993-01-01

    This paper presents a case study of the knowledge engineering process employed to support the Link Monitor and Control Operator Assistant (LMCOA). The LMCOA is a prototype system which automates the configuration, calibration, test, and operation (referred to as precalibration) of the communications, data processing, metric data, antenna, and other equipment used to support space-ground communications with deep space spacecraft in NASA's Deep Space Network (DSN). The primary knowledge base in the LMCOA is the Temporal Dependency Network (TDN), a directed graph which provides a procedural representation of the precalibration operation. The TDN incorporates precedence, temporal, and state constraints and uses several supporting knowledge bases and data bases. The paper provides a brief background on the DSN, and describes the evolution of the TDN and supporting knowledge bases, the process used for knowledge engineering, and an analysis of the successes and problems of the knowledge engineering effort.

  20. Pushing the P300-based brain-computer interface beyond 100 bpm: extending performance guided constraints into the temporal domain.

    Science.gov (United States)

    Townsend, G; Platsko, V

    2016-04-01

    A new presentation paradigm for the P300-based brain-computer interface (BCI) referred to as the 'asynchronous paradigm' (ASP) is introduced and studied. It is based on the principle of performance guided constraints (Townsend et al 2012 Neurosci. Lett. 531 63-8) extended from the spatial domain into the temporal domain. The traditional constraint of flashing targets in predefined constant epochs of time is eliminated and targets flash asynchronously with timing based instead on constraints intended to improve performance. We propose appropriate temporal constraints to derive the ASP and compare its performance to that of the 'checkerboard paradigm' (CBP), which has previously been shown to be superior to the standard 'row/column paradigm' introduced by Farwell and Donchin (1988 Electroencephalogr. Clin. Neurophysiol. 70 510-23). Ten participants were tested in the ASP and CBP conditions both with traditional flashing items and with flashing faces in place of the targets (see Zhang et al 2012 J. Neural Eng. 9 026018; Kaufmann and Kübler 2014 J. Neural Eng. 11 ; Chen et al 2015 J. Neurosci. Methods 239 18-27). Eleven minutes of calibration data were used as input to a stepwise linear discriminant analysis to derive classification coefficients used for online classification. Accuracy was consistently high for both paradigms (87% and 93%) while information transfer rate was 45% higher for the ASP than the CBP. In a free spelling task, one subject spelled a 66 character sentence (from a 72 item matrix) with 100% accuracy in 3 min and 24 s demonstrating a practical throughput of 120 bits per minute (bpm) with a theoretical upper bound of 258 bpm. The subject repeated the task three times in a row without error. This work represents an advance in P300 speller technology and raises the ceiling that was being reached on P300-based BCIs. Most importantly, the research presented here is a novel and effective general strategy for organising timing for flashing items. The ASP

  1. Spatio-temporal monitoring of cotton cultivation using ground-based and airborne multispectral sensors in GIS environment.

    Science.gov (United States)

    Papadopoulos, Antonis; Kalivas, Dionissios; Theocharopoulos, Sid

    2017-07-01

    Multispectral sensor capability of capturing reflectance data at several spectral channels, together with the inherent reflectance responses of various soils and especially plant surfaces, has gained major interest in crop production. In present study, two multispectral sensing systems, a ground-based and an aerial-based, were applied for the multispatial and temporal monitoring of two cotton fields in central Greece. The ground-based system was Crop Circle ACS-430, while the aerial consisted of a consumer-level quadcopter (Phantom 2) and a modified Hero3+ Black digital camera. The purpose of the research was to monitor crop growth with the two systems and investigate possible interrelations between the derived well-known normalized difference vegetation index (NDVI). Five data collection campaigns were conducted during the cultivation period and concerned scanning soil and plants with the ground-based sensor and taking aerial photographs of the fields with the unmanned aerial system. According to the results, both systems successfully monitored cotton growth stages in terms of space and time. The mean values of NDVI changes through time as retrieved by the ground-based system were satisfactorily modelled by a second-order polynomial equation (R 2 0.96 in Field 1 and 0.99 in Field 2). Further, they were highly correlated (r 0.90 in Field 1 and 0.74 in Field 2) with the according values calculated via the aerial-based system. The unmanned aerial system (UAS) can potentially substitute crop scouting as it concerns a time-effective, non-destructive and reliable way of soil and plant monitoring.

  2. Ontology-based time information representation of vaccine adverse events in VAERS for temporal analysis

    Directory of Open Access Journals (Sweden)

    Tao Cui

    2012-12-01

    Full Text Available Abstract Background The U.S. FDA/CDC Vaccine Adverse Event Reporting System (VAERS provides a valuable data source for post-vaccination adverse event analyses. The structured data in the system has been widely used, but the information in the write-up narratives is rarely included in these kinds of analyses. In fact, the unstructured nature of the narratives makes the data embedded in them difficult to be used for any further studies. Results We developed an ontology-based approach to represent the data in the narratives in a “machine-understandable” way, so that it can be easily queried and further analyzed. Our focus is the time aspect in the data for time trending analysis. The Time Event Ontology (TEO, Ontology of Adverse Events (OAE, and Vaccine Ontology (VO are leveraged for the semantic representation of this purpose. A VAERS case report is presented as a use case for the ontological representations. The advantages of using our ontology-based Semantic web representation and data analysis are emphasized. Conclusions We believe that representing both the structured data and the data from write-up narratives in an integrated, unified, and “machine-understandable” way can improve research for vaccine safety analyses, causality assessments, and retrospective studies.

  3. Normalization of cardiac substrate utilization and left ventricular hypertrophy precede functional recovery in heart failure regression.

    Science.gov (United States)

    Byrne, Nikole J; Levasseur, Jody; Sung, Miranda M; Masson, Grant; Boisvenue, Jamie; Young, Martin E; Dyck, Jason R B

    2016-05-15

    Impaired cardiac substrate metabolism plays an important role in heart failure (HF) pathogenesis. Since many of these metabolic changes occur at the transcriptional level of metabolic enzymes, it is possible that this loss of metabolic flexibility is permanent and thus contributes to worsening cardiac function and/or prevents the full regression of HF upon treatment. However, despite the importance of cardiac energetics in HF, it remains unclear whether these metabolic changes can be normalized. In the current study, we investigated whether a reversal of an elevated aortic afterload in mice with severe HF would result in the recovery of cardiac function, substrate metabolism, and transcriptional reprogramming as well as determined the temporal relationship of these changes. Male C57Bl/6 mice were subjected to either Sham or transverse aortic constriction (TAC) surgery to induce HF. After HF development, mice with severe HF (% ejection fraction hypertrophy/HF were returned to values observed in healthy controls. Interestingly, pressure-overload-induced left ventricular hypertrophy (LVH) and cardiac substrate metabolism were restored at 1-week post-DB, which preceded functional recovery. The regression of severe HF is associated with early and dramatic improvements in cardiac energy metabolism and LVH normalization that precede restored cardiac function, suggesting that metabolic and structural improvements may be critical determinants for functional recovery. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2016. For permissions please email: journals.permissions@oup.com.

  4. A Predictive Risk Model for A(H7N9) Human Infections Based on Spatial-Temporal Autocorrelation and Risk Factors: China, 2013–2014

    Science.gov (United States)

    Dong, Wen; Yang, Kun; Xu, Quan-Li; Yang, Yu-Lian

    2015-01-01

    This study investigated the spatial distribution, spatial autocorrelation, temporal cluster, spatial-temporal autocorrelation and probable risk factors of H7N9 outbreaks in humans from March 2013 to December 2014 in China. The results showed that the epidemic spread with significant spatial-temporal autocorrelation. In order to describe the spatial-temporal autocorrelation of H7N9, an improved model was developed by introducing a spatial-temporal factor in this paper. Logistic regression analyses were utilized to investigate the risk factors associated with their distribution, and nine risk factors were significantly associated with the occurrence of A(H7N9) human infections: the spatial-temporal factor φ (OR = 2546669.382, p 0.70) of the predictive risk map, whereas 44.6% (45/101) of which overlaid on the high risk areas (the predictive risk > 0.70) for the traditional model, and the fitting accuracy of the improved model was 91.6% which was superior to the traditional model (86.1%). The predictive risk map generated based on the improved model revealed that the east and southeast of China were the high risk areas of A(H7N9) human infections in February 2014. These results provided baseline data for the control and prevention of future human infections. PMID:26633446

  5. A Predictive Risk Model for A(H7N9) Human Infections Based on Spatial-Temporal Autocorrelation and Risk Factors: China, 2013-2014.

    Science.gov (United States)

    Dong, Wen; Yang, Kun; Xu, Quan-Li; Yang, Yu-Lian

    2015-12-01

    This study investigated the spatial distribution, spatial autocorrelation, temporal cluster, spatial-temporal autocorrelation and probable risk factors of H7N9 outbreaks in humans from March 2013 to December 2014 in China. The results showed that the epidemic spread with significant spatial-temporal autocorrelation. In order to describe the spatial-temporal autocorrelation of H7N9, an improved model was developed by introducing a spatial-temporal factor in this paper. Logistic regression analyses were utilized to investigate the risk factors associated with their distribution, and nine risk factors were significantly associated with the occurrence of A(H7N9) human infections: the spatial-temporal factor φ (OR = 2546669.382, p 0.70) of the predictive risk map, whereas 44.6% (45/101) of which overlaid on the high risk areas (the predictive risk > 0.70) for the traditional model, and the fitting accuracy of the improved model was 91.6% which was superior to the traditional model (86.1%). The predictive risk map generated based on the improved model revealed that the east and southeast of China were the high risk areas of A(H7N9) human infections in February 2014. These results provided baseline data for the control and prevention of future human infections.

  6. Io’s volcanoes at high spatial, spectral, and temporal resolution from ground-based observations

    Science.gov (United States)

    de Kleer, Katherine R.; de Pater, Imke

    2017-10-01

    Io’s dynamic volcanic eruptions provide a laboratory for studying large-scale volcanism on a body vastly different from Earth, and for unraveling the connections between tidal heating and the geological activity it powers. Ground-based near-infrared observatories allow for high-cadence, long-time-baseline observing programs using diverse instrumentation, and yield new information into the nature and variability of this activity. I will summarize results from four years of ground-based observations of Io’s volcanism, including: (1) A multi-year cadence observing campaign using adaptive optics on 8-10 meter telescopes, which places constraints on tidal heating models through sampling the spatial distribution of Io’s volcanic heat flow, and provides estimates of the occurrence rate of Io’s most energetic eruptions; (2) High-spectral-resolution (R~25,000) studies of Io’s volcanic SO gas emission at 1.7 microns, which resolves this rovibronic line into its different branches, and thus contains detailed information on the temperature and thermal state of the gas; and (3) The highest-spatial-resolution map ever produced of the entire Loki Patera, a 20,000 km2 volcanic feature on Io, derived from adaptive-optics observations of an occultation of Io by Europa. The map achieves a spatial resolution of ~10 km and indicates compositional differences across the patera. These datasets both reveal specific characteristics of Io’s individual eruptions, and provide clues into the sub-surface systems connecting Io’s tidally-heated interior to its surface expressions of volcanism.

  7. Temporal epilepsy lesions may be detected by the voxel-based quantitative analysis of brain FDG-PET images using an original block-matching normalization software.

    Science.gov (United States)

    Verger, Antoine; Yagdigul, Yalcin; Van Der Gucht, Axel; Poussier, Sylvain; Guedj, Eric; Maillard, Louis; Malandain, Grégoire; Hossu, Gabriela; Fay, Renaud; Karcher, Gilles; Marie, Pierre-Yves

    2016-05-01

    Statistical parametric mapping (SPM) provides useful voxel-by-voxel analyses of brain images from (18)F-fluorodesoxyglucose positron emission tomography (FDG-PET) after an initial step of spatial normalization through an anatomical template model. In the setting of the preoperative workup of patients with temporal epilepsy, this study aimed at assessing a block-matching (BM) normalization method, where most transformations are computed through small blocks, a principle that minimizes artefacts and overcomes additional image-filtering. Brain FDG-PET images from 31 patients with well-characterised temporal lobe epilepsy and among whom 22 had common mesial temporal lobe epilepsy were retrospectively analysed using both BM and conventional SPM normalization methods and with PET images from age-adjusted controls. Different threshold p values corrected for cluster volume were considered (0.01, 0.005, and 0.001). The use of BM provided equivalent values to those of SPM with regard to the overall volumes of temporal and extra-temporal hypometabolism, as well as similar sensitivity for detecting the involved temporal lobe, reaching 87 and 94 % for SPM and BM, respectively, at a threshold p value of 0.01. However, the ability to more accurately localize brain lesions within the mesial portion of the temporal lobe was a little higher with BM than with SPM with respective sensitivities reaching 78 % for BM and 45 % for SPM (p < 0.05). BM normalization compares well with conventional SPM for the voxel-based quantitative analysis of the FDG-PET images from temporal epilepsy patients. Further studies in different population are needed to determine whether BM is truly an accurate alternative to SPM in this setting.

  8. [Spatio-temporal variability of habitat quality in Beijing-Tianjin-Hebei Area based on land use change].

    Science.gov (United States)

    Wu, Jian-sheng; Cao, Qi-wen; Shi, Shu-qin; Huang, Xiu-lan; Lu, Zhi-qiang

    2015-11-01

    Land use change is the core content of global change. To achieve sustainable land use planning, it is necessary to evaluate the habitat quality pattern and its spatio-temporal variation resulted from land use change, which can provide basis for the formulation of land management policy. Based on the analysis of land use change from 2000 to 2010, this study investigated the spatio-temporal variation of habitat quality pattern of Beijing-Tianjin-Hebei Area. We used the watershed profile sampling points and spatial autocorrelation analysis based on watershed subdivision. The results showed that the main land use change types from 2000 to 2010 in this area included the transition from cultivated land to construction land, the transition between forest and grassland, and the transition from water bodies to cultivated land. This land use/cover change process led to the decrease of heterogeneity of landscape structure and increase of fragmentation. The overall spatial pattern of habitat quality was that southeast and south areas were relatively lower, while north and west areas were relatively higher. The analysis based on watershed profile showed that the habitat quality of each watershed presented significant difference in each part. Habitat quality of most sampling points degraded in a way, while some improved compared with 2000. In general, the habitat quality of the bottom part of Luanhe River basin, the medium part of Bai-Chaobai-Chaobaixin River basin, the medium and the bottom part of Yongding River basin and medium part of Laozhang-Fudongpai- Beipai River basin were poor and volatile, while other parts were relatively good. There was a decreasing agglomeration characteristic of distribution of habitat quality in Beijing-Tianjin-Hebei Area under the disturbance of human activities. Areas of high habitat quality in 2000 were mainly located in Luanhe River basin and top part of Baihe basin. Areas of low habitat quality were mainly located in medium and bottom part

  9. Temporal and spatial water use on irrigated and nonirrigated pasture-based dairy farms.

    Science.gov (United States)

    Higham, C D; Horne, D; Singh, R; Kuhn-Sherlock, B; Scarsbrook, M R

    2017-08-01

    Robust information for water use on pasture-based dairy farms is critical to farmers' attempts to use water more efficiently and the improved allocation of freshwater resources to dairy farmers. To quantify the water requirements of dairy farms across regions in a practicable manner, it will be necessary to develop predictive models. The objectives of this study were to compare water use on a group of irrigated and nonirrigated farms, validate existing water use models using the data measured on the group of nonirrigated farms, and modify the model so that it can be used to predict water use on irrigated dairy farms. Water use data were collected on a group of irrigated dairy farms located in the Canterbury, New Zealand, region with the largest area under irrigation. The nonirrigated farms were located in the Manawatu region. The amount of water used for irrigation was almost 52-fold greater than the amount of all other forms of water use combined. There were large differences in measured milking parlor water use, stock drinking water, and leakage rates between the irrigated and nonirrigated farms. As expected, stock drinking water was lower on irrigated dairy farms. Irrigation lowers the dry matter percentage of pasture, ensuring that the amount of water ingested from pasture remains high throughout the year, thereby reducing the demand for drinking water. Leakage rates were different between the 2 groups of farms; 47% of stock drinking water was lost as leakage on nonirrigated farms, whereas leakage on the irrigated farms equated to only 13% of stock drinking water. These differences in leakage were thought to be related to regional differences rather than differences in irrigated versus nonirrigated farms. Existing models developed to predict milking parlor, corrected stock drinking water, and total water use on nonirrigated pasture-based dairy farms in a previous related study were tested on the data measured in the present research. As expected, these models

  10. Ice thickness estimations based on multi-temporal glacier inventories - potential and challenges

    Science.gov (United States)

    Helfricht, Kay; Huss, Matthias; Otto, Jan-Christoph

    2016-04-01

    The ongoing glacier retreat exposes a large number of surface depressions in the former glacier bed that can be filled with water or act as sediment traps. This has already been observed at various sites in Austria and in other mountain areas worldwide. The formation of glacial lakes can constitute an important environmental and socio-economic impact on high mountain systems including water resource management, sediment delivery, natural hazards, energy production and tourism. In general, information on ice thickness distribution is the basis for simulating future glacier change. We used the approach proposed by Huss and Farinotti (2012) to model the ice thickness distribution and potential locations of subglacial depressions. The study is part of the FUTURELAKE project that seeks to model the formation of new glacier lakes and their possible future evolution in the Austria Alps. The required data on glacier extent, surface elevation and slope were taken from the Austrian Glacier Inventories GI1 from 1969, GI2 from 1998 and GI3 from2006 (Fischer et al., 2015). The different glacier outlines and surface elevations from the inventories enable us to evaluate (i) the robustness of the modelled bedrock depressions with respect to different glacier settings, (ii) the power of the model to simulate recently formed glacial lakes, (iii) the similarities in calculated ice thickness distributions across the inventories and (iv) the feasibility of simulating observed changes in ice thickness and glacier volume. In general, the modelled localization of large potential depressions was relatively stable using the observed glacier settings. A number of examples show that recently formed glacial lakes could be detected by the model based on previous glacier extents. The locations of maximum ice depths within different elevation zones appeared to be sensitive to changes in glacier width. However, observed ice thickness changes and, thus, volume changes between the inventories could

  11. Towards Temporal Graph Databases

    OpenAIRE

    Campos, Alexander; Mozzino, Jorge; Vaisman, Alejandro

    2016-01-01

    In spite of the extensive literature on graph databases (GDBs), temporal GDBs have not received too much attention so far. Temporal GBDs can capture, for example, the evolution of social networks across time, a relevant topic in data analysis nowadays. In this paper we propose a data model and query language (denoted TEG-QL) for temporal GDBs, based on the notion of attribute graphs. This allows a straightforward translation to Neo4J, a well-known GBD. We present extensive examples of the use...

  12. Spatio-temporal variability of upwelling along the southwest coast of India based on satellite observations

    Science.gov (United States)

    Jayaram, Chiranjivi; Kumar, P. K. Dinesh

    2018-03-01

    Upwelling phenomenon along the eastern boundaries of global ocean has received greater attention in the recent times due to its environmental and economic significance in the global warming and the scenario of changing climate as opined by IPCC AR5. In this context, the availabile satellite data on sea surface winds, sea surface temperature (SST), sea level anomaly (SLA) and chlorophyll-a concentration (Chl-a), for the period 1981-2016 were analyzed to identify the coastal upwelling pattern in the Southeastern Arabian Sea (SEAS). Synergistic approach, using winds, SST, SLA and Chl-a revealed that strong upwelling was prevailing between 8°N and 12°N. During the study period, geographical differences existed in the peak values of upwelling favorable conditions considered for study. Analysis of the alongshore winds which are conducive for upwelling were observed to be curtailed towards the northern part of the study region between 2005 and 2010. Also, the strength of upwelling reduced during the strong ENSO years of 1997 and 2015. Linear regression based trend analysis of upwelling indices like Ekman transport, SST and chlorophyll along the coast, during the upwelling period, revealed slight increase in the strength towards the southern region while it decreased to the north during the study period.

  13. EXTRACTING TEMPORAL AND SPATIAL DISTRIBUTIONS INFORMATION ABOUT ALGAL GLOOMS BASED ON MULTITEMPORAL MODIS

    Directory of Open Access Journals (Sweden)

    L. Chunguang

    2012-07-01

    Full Text Available Based on MODIS remote sensing data, method and technology to extraction the time and space distribution information of algae bloom is studied and established. The dynamic feature of time and space in Taihu Lake from 2009 to 2011 can be obtained by extracted method. Variation of cyanobacterial bloom in the Taihu Lake is analyzed and discussed. The algae bloom frequency index (AFI and algae bloom sustainability index (ASI is important criterion which can show the interannual and inter-monthly variation in the whole area or the subregion of Taihu Lake. Utilizing the AFI and ASI from 2009 to 2011, it found some phenomena that: the booming frequency decreased from the north and west to the East and South of Taihu Lake. The annual month algae bloom variation of AFI reflect the booming existing twin peaks in the high shock level and lag trend in general. In the subregion statistics, the IBD and ASI in 2011 show the abnormal condition in the border between the Gongshan Bay and Central Lake. The date is obvious earlier than that on the same subregion in previous years and that on others subregion in the same year.

  14. Evaluation of groundwater discharge into small lakes based on the temporal distribution of radon-222

    Science.gov (United States)

    Dimova, N.T.; Burnett, W.C.

    2011-01-01

    In order to evaluate groundwater discharge into small lakes we constructed a model that is based on the budget of 222Rn (radon t1/2 5 3.8 d) as a tracer. The main assumptions in our model are that the lake's waters are wellmixed horizontally and vertically; the only significant 222Rn source is via groundwater discharge; and the only losses are due to decay and atmospheric evasion. In order to evaluate the groundwater-derived 222Rn flux, we monitored the 222Rn concentration in lake water over periods long enough (usually 1-3 d) to observe changes likely caused by variations in atmospheric exchange (primarily a function of wind speed and temperature). We then attempt to reproduce the observed record by accounting for decay and atmospheric losses and by estimating the total 222Rn input flux using an iterative approach. Our methodology was tested in two lakes in central Florida: one of which is thought to have significant groundwater inputs (Lake Haines) and another that is known not to have any groundwater inflows but requires daily groundwater augmentation from a deep aquifer (Round Lake). Model results were consistent with independent seepage meter data at both Lake Haines (positive seepage of ??? 1.6 ?? 104 m3 d-1 in Mar 2008) and at Round Lake (no net groundwater seepage). ?? 2011, by the American Society of Limnology and Oceanography, Inc.

  15. Suppression of Repeat-Intensive False Targets Based on Temporal Pulse Diversity

    Directory of Open Access Journals (Sweden)

    Gang Lu

    2013-01-01

    Full Text Available This paper considers the problem of suppressing the repeat-intensive false targets produced by a deception electronic attack (EA system equipped with a Digital Radio Frequency Memory (DRFM device. Different from a conventional repeat jammer, this type of jamming intensively retransmits the intercepted signal stored in a DRFM to the victim radar in a very short time-delay interval relative to a radar pulse wide. A multipeak matched-filtering output is then produced other than the merely expected true target. An electronic protection (EP algorithm based on the space time block code (STBC is proposed to suppress the adverse effects of this jammer. By transmitting a pulse sequence generated from the STBC in succession and the following cancellation process applied upon the received signal, this algorithm performs successfully in a single antenna system provided that the target models are nonfluctuating or slow fluctuating and the pulse repetition frequency (PRF is comparatively high. The performance in white and correlated Gaussian disturbance is evaluated by means of Monte Carlo simulations.

  16. Temporal variability of the Baltic Sea level based on satellite observations

    Science.gov (United States)

    Stramska, Malgorzata

    2013-11-01

    The main objective of this paper is to determine what are the most important time scales of variability of the sea level in the open Baltic Sea. The study is based on the 7-day resolution multimission global gridded sea level anomalies (SLA) for years 1992-2012 distributed by AVISO. For comparison satellite-derived SLA from the North Sea and North Atlantic, coastal data from the Stockholm tide gauge, the NCEP meteorological data, and river runoff data from the Balt-HYPE model have been also analyzed. We have applied time series analysis algorithms (Bendat and Piersol, 2011). Supporting earlier research, our results show that the variability of the sea level in the open Baltic Sea is highly coherent with the sea level in the North Sea. We have found out that the annual peak is not well pronounced in the open Baltic Sea SLA spectrum, but the semiannual peak is the most prevailing. In contrast, the annual peak is significant in the North Sea SLA power spectrum. The coherence between the open Baltic Sea and the Stockholm SLA is high and the SLA variability in these two locations is in phase. The results of the cross-spectral analysis between the SLA in the Baltic Sea and meteorological parameters (wind stress magnitude, zonal and meridional wind stress components, and barometric pressure at sea level) show that coherence is highest with the zonal wind stress component. Coherence between the river runoff and the SLA in Stockholm is not significant.

  17. Spatio-temporal-based joint range and angle estimation for wideband signals

    Science.gov (United States)

    Villemin, Guilhem; Fossati, Caroline; Bourennane, Salah

    2013-12-01

    Object localization using active sensor network exploiting the scattering of the emitted waves by a transmitter has been drawing a lot of research interest in the last years. For most applications, the environment leads to the arrival of multiple signals corresponding to emitted signal, signals which are scattered by the objects, and noise. In practical systems, the signals impinging on an array are frequently correlated, and the object number rapidly exceeds the number of sensors, making unsuitable most high-resolution methods used in array processing. We propose a solution to overcome these two experimental constraints. Firstly, frequential smoothing is used to decorrelate the scattered signals, enabling the estimation of their time delays of arrival (TDOA), using subspace-based methods. Secondly, an efficient algorithm for source localization using the TDOA is proposed. The advantage of the developed method is its efficiency even if the number of sources is larger than the number of sensors, in the presence of correlated signals. The performances of the proposed method are assessed on simulated signals. The results on real-world data are also presented and analyzed.

  18. An inertial sensor-based system for spatio-temporal analysis in classic cross-country skiing diagonal technique.

    Science.gov (United States)

    Fasel, Benedikt; Favre, Julien; Chardonnens, Julien; Gremion, Gérald; Aminian, Kamiar

    2015-09-18

    The present study proposes a method based on ski fixed inertial sensors to automatically compute spatio-temporal parameters (phase durations, cycle speed and cycle length) for the diagonal stride in classical cross-country skiing. The proposed system was validated against a marker-based motion capture system during indoor treadmill skiing. Skiing movement of 10 junior to world-cup athletes was measured for four different conditions. The accuracy (i.e. median error) and precision (i.e. interquartile range of error) of the system was below 6 ms for cycle duration and ski thrust duration and below 35 ms for pole push duration. Cycle speed precision (accuracy) was below 0.1m/s (0.00 5m/s) and cycle length precision (accuracy) was below 0.15m (0.005 m). The system was sensitive to changes of conditions and was accurate enough to detect significant differences reported in previous studies. Since capture volume is not limited and setup is simple, the system would be well suited for outdoor measurements on snow. Copyright © 2015 Elsevier Ltd. All rights reserved.

  19. Detecting Damaged Building Regions Based on Semantic Scene Change from Multi-Temporal High-Resolution Remote Sensing Images

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    Jihui Tu

    2017-04-01

    Full Text Available The detection of damaged building regions is crucial to emergency response actions and rescue work after a disaster. Change detection methods using multi-temporal remote sensing images are widely used for this purpose. Differing from traditional methods based on change detection for damaged building regions, semantic scene change can provide a new point of view since it can indicate the land-use variation at the semantic level. In this paper, a novel method is proposed for detecting damaged building regions based on semantic scene change in a visual Bag-of-Words model. Pre- and post-disaster scene change in building regions are represented by a uniform visual codebook frequency. The scene change of damaged and non-damaged building regions is discriminated using the Support Vector Machine (SVM classifier. An evaluation of experimental results, for a selected study site of the Longtou hill town of Yunnan, China, which was heavily damaged in the Ludian earthquake of 14 March 2013, shows that this method is feasible and effective for detecting damaged building regions. For the experiments, WorldView-2 optical imagery and aerial imagery is used.

  20. Estimation of temporal evolution of the helium plasmasphere based on a sequence of IMAGE/EUV images

    Science.gov (United States)

    Nakano, S.; Fok, M.-C.; Brandt, P. C.; Higuchi, T.

    2014-05-01

    We have developed a technique for estimating the temporal evolution of the plasmaspheric helium ion density based on a sequence of extreme ultraviolet (EUV) data obtained from the IMAGE satellite. In the proposed technique, the estimation is obtained by incorporating EUV images from IMAGE into a two-dimensional fluid model of the plasmasphere using a data assimilation approach based on the ensemble transform Kalman filter. Since the motion and the spatial structure of the helium plasmasphere is strongly controlled by the electric field in the inner magnetosphere, the electric field around the plasmapause can also be estimated using the ensemble transform Kalman filter. We performed an experiment using synthetic images that were generated from the same numerical model under a certain condition. It was confirmed that the condition that generated the synthetic images was successfully reproduced. We also present some results obtained using real EUV imaging data. Finally, we discuss the possibility of estimating the density profile along a magnetic field line. Since each EUV image was taken from a different direction due to the motion of the IMAGE satellite, we could obtain the information on the density profile along a field line by combining multiple images.

  1. Monitoring of the temporal and spatial variation of groundwater storage in the Three Gorges area based on the CORS network

    Science.gov (United States)

    Wang, Wei; Zhang, Chuanyin; Liang, Shiming; Yang, Qiang; Hu, MinZhang; Feng, Wei

    2017-11-01

    The variation of groundwater storage is not well understood due to the complex hydrodynamic environment in the Three Gorges area. The variation of monthly groundwater storage from January 2011 to June 2015 was directly inverted in the Three Gorges area of China based on 26 Continuously Operating Reference Station (CORS) and eight gravity stations with a resolution of 2‧ × 2‧ using the Earth's gravity field and the load deformation theory. The results were then compared with the water level from groundwater monitoring wells. The comparison indicates that it is possible to calculate the temporal and spatial variation of groundwater with high precision based on the continuous observation data of CORS and a small amount of gravity stations. Our analysis shows that the groundwater storage was consistent in the Three Gorges area from 2011 to 2014. The Three Gorges Reservoir has a large impact on the variation of groundwater storage. The variation of the groundwater storage derived from CORS agrees well with that of the groundwater monitoring wells. The new data are important references for the research of hydrodynamic environmental change in the Three Gorges area and for the analysis of the impact of water impoundment and drainage in the Three Gorges Reservoir.

  2. The “Natural” History of Medically Treated Temporal Lobe Epilepsy: What Can an Evidence-Based Approach Tell Us?

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    Colin Bruce Josephson

    2012-01-01

    Full Text Available We systematically reviewed the literature to describe the “natural” history of medically treated temporal lobe epilepsy (TLE. No population-based studies recruiting incident cases of TLE irrespective of age exist. Prospective, population-based studies were limited to those recruiting only childhood-onset TLE or those reporting TLE as a subgroup of cohorts of focal epilepsies. Few studies have been performed in the “MRI era” limiting information on natural history secondary to specific pathologies. Available data suggests that TLE is highly variable, with unpredictable transient remissions and low rates of seizure freedom (30 to 50%. Etiology and failure of first and second drug seem to be the most important predictors for treatment prognosis. The role of initial precipitating injuries remains speculative, as imaging information of related events is either missing or conflicting. Prospective cohorts of new-onset TLE with long-term followup using advanced MRI techniques, timely EEG recordings, and assessments of psychiatric comorbidities are needed.

  3. Real-Time Sound Source Localization for a Mobile Robot Based on the Guided Spectral-Temporal Position Method

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    Xiaofei Li

    2012-09-01

    Full Text Available Sound source localization based on a microphone array for mobile robots faces great challenges because of factors such as uncertainty of the robot's movement, noise and reverberation, the requirements of a compact microphone array and so on. This paper studies a method for sound source localization in a dynamic environment using a cross-microphone array plane, which consists of four microphones on an intelligent mobile robot platform. Firstly, the method of spectral subtraction and campestral mean normalization is introduced to de-noise. Then GCC-PHAT-ργ and the guided spectral-temporal (ST position method are proposed to suppress noise and reverberation based on the generalized cross-correlation method to estimate time delay. Finally, the sound source is positioned by adopting the geometric location method. This system is tested by a total of 2,016 sets of experiments. Even in an intensely noisy and reverberating environment, the guided ST position method achieves angle positioning accuracy of more than 95% with a less than 15 degrees localization error. Meanwhile, all the experimental data can be processed in real-time, within 0.4s.

  4. Multivoxel patterns in face-sensitive temporal regions reveal an encoding schema based on detecting life in a face.

    Science.gov (United States)

    Looser, Christine E; Guntupalli, Jyothi S; Wheatley, Thalia

    2013-10-01

    More than a decade of research has demonstrated that faces evoke prioritized processing in a 'core face network' of three brain regions. However, whether these regions prioritize the detection of global facial form (shared by humans and mannequins) or the detection of life in a face has remained unclear. Here, we dissociate form-based and animacy-based encoding of faces by using animate and inanimate faces with human form (humans, mannequins) and dog form (real dogs, toy dogs). We used multivariate pattern analysis of BOLD responses to uncover the representational similarity space for each area in the core face network. Here, we show that only responses in the inferior occipital gyrus are organized by global facial form alone (human vs dog) while animacy becomes an additional organizational priority in later face-processing regions: the lateral fusiform gyri (latFG) and right superior temporal sulcus. Additionally, patterns evoked by human faces were maximally distinct from all other face categories in the latFG and parts of the extended face perception system. These results suggest that once a face configuration is perceived, faces are further scrutinized for whether the face is alive and worthy of social cognitive resources.

  5. Temporal properties of stereopsis

    Science.gov (United States)

    Gheorghiu, E.

    2005-03-01

    The goal of the research presented in this thesis was to investigate temporal properties of disparity processing and depth perception in human subjects, in response to dynamic stimuli. The results presented in various chapters, reporting findings about different temporal aspects of disparity processing, are based on psychophysical experiments and computational model analysis. In chapter 1 we investigated which processes of binocular depth perception in dynamic random-dot stereograms (DRS), i.e., tolerance for interocular delays and temporal integration of correlation, are responsible for the temporal flexibility of the stereoscopic system. Our results demonstrate that (i) disparities from simultaneous monocular inputs dominate those from interocular delayed inputs; (ii) stereopsis is limited by temporal properties of monocular luminance mechanisms; (iii) depth perception in DRS results from cross-correlation-like operation on two simultaneous monocular inputs that represent the retinal images after having been subjected to a process of monocular temporal integration of luminance. In chapter 2 we examined what temporal information is exploited by the mechanisms underlying stereoscopic motion in depth. We investigated systematically the influence of temporal frequency on binocular depth perception in temporally correlated and temporally uncorrelated DRS. Our results show that disparity-defined depth is judged differently in temporally correlated and uncorrelated DRS above a temporal frequency of about 3 Hz. The results and simulations indicate that: (i) above about 20 Hz, the complete absence of stereomotion is caused by temporal integration of luminance; (ii) the difference in perceived depth in temporally correlated and temporally uncorrelated DRS for temporal frequencies between 20 and 3 Hz, is caused by temporal integration of disparity. In chapter 3 we investigated temporal properties of stereopsis at different spatial scales in response to sustained and

  6. Cardiac tamponade preceding skin involvement in systemic sclerosis

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    L. Bozzola

    2011-09-01

    Full Text Available The frequency of pericardial involvement in Systemic Sclerosis (SSc is high on autoptic or echocardiographic studies, but the clinical recognition of pericarditis with or without effusion is rare. We describe a case of a 71-year-old female with no previous history of heart disease, who presented with a large pericardial effusion and tamponade that required pericardial drain. She had suffered from Raynaud’s phenomenon since 25 years. Six weeks after hospital discharge she complained of skin hardening on left leg. Pericardial tamponade is a very rare manifestation of SSc and occurs both early or late in the course of the disease, but in our case it preceded the recognition of scleroderma. We have only identified two other cases of pericardial effusion preceding cutaneous involvement in scleroderma.

  7. Predicting clinical symptoms of attention deficit hyperactivity disorder based on temporal patterns between and within intrinsic connectivity networks.

    Science.gov (United States)

    Wang, Xun-Heng; Jiao, Yun; Li, Lihua

    2017-10-24

    Attention deficit hyperactivity disorder (ADHD) is a common brain disorder with high prevalence in school-age children. Previously developed machine learning-based methods have discriminated patients with ADHD from normal controls by providing label information of the disease for individuals. Inattention and impulsivity are the two most significant clinical symptoms of ADHD. However, predicting clinical symptoms (i.e., inattention and impulsivity) is a challenging task based on neuroimaging data. The goal of this study is twofold: to build predictive models for clinical symptoms of ADHD based on resting-state fMRI and to mine brain networks for predictive patterns of inattention and impulsivity. To achieve this goal, a cohort of 74 boys with ADHD and a cohort of 69 age-matched normal controls were recruited from the ADHD-200 Consortium. Both structural and resting-state fMRI images were obtained for each participant. Temporal patterns between and within intrinsic connectivity networks (ICNs) were applied as raw features in the predictive models. Specifically, sample entropy was taken asan intra-ICN feature, and phase synchronization (PS) was used asan inter-ICN feature. The predictive models were based on the least absolute shrinkage and selectionator operator (LASSO) algorithm. The performance of the predictive model for inattention is r=0.79 (p<10(-8)), and the performance of the predictive model for impulsivity is r=0.48 (p<10(-8)). The ICN-related predictive patterns may provide valuable information for investigating the brain network mechanisms of ADHD. In summary, the predictive models for clinical symptoms could be beneficial for personalizing ADHD medications. Copyright © 2017 IBRO. Published by Elsevier Ltd. All rights reserved.

  8. Pyoderma gangrenosum Preceding the diagnosis of systemic lupus erythematosus.

    Science.gov (United States)

    Waldman, Mark A; Callen, Jeffrey P

    2005-01-01

    Patients with systemic lupus erythematosus (SLE) often develop leg ulceration, particularly those with antiphospholipid antibodies or with vasculitis. Pyoderma gangrenosum (PG) is an idiopathic ulcerative neutrophilic dermatosis that is commonly associated with inflammatory bowel disease or seronegative polyarthritis. Although PG-like lesions have been commonly described in patients with the antiphospholipid antibody syndrome, the occurrence of PG as a preceding manifestation of SLE has only rarely been reported. We present a patient who developed PG roughly 8 years prior to developing SLE.

  9. Efficient and Flexible Crowdsourcing of Specialized Tasks with Precedence Constraints

    OpenAIRE

    Chatterjee, Avhishek; Borokhovich, Michael; Varshney, Lav R.; Vishwanath, Sriram

    2016-01-01

    Many companies now use crowdsourcing to leverage external (as well as internal) crowds to perform specialized work, and so methods of improving efficiency are critical. Tasks in crowdsourcing systems with specialized work have multiple steps and each step requires multiple skills. Steps may have different flexibilities in terms of obtaining service from one or multiple agents, due to varying levels of dependency among parts of steps. Steps of a task may have precedence constraints among them....

  10. Bipolar disorder preceding the onset of multiple sclerosis

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    Ciro Marangoni

    2015-01-01

    Full Text Available Multiple sclerosis (MS is the most common inflammatory demyelinating brain disease. The occurrence of psychiatric disorders, especially for major depression, in the course of MS is high. Reports concerning bipolar disorder (BD remain rather scarce although early descriptions were found in the old neurological literature. The purpose of this article is to provide a critical review of the epidemiology, comorbidity, and treatment findings regarding BD preceding the onset of MS.

  11. Bereitschaftspotential preceding eyelid blinks in Parkinson’s disease

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    Isabella Araújo Mota

    Full Text Available ABSTRACT The Bereitschaftspotential (BP is a negative wave observed in EEG retrograde averaging, preceding a motor act. The objective was to study the BP preceding voluntary eyelid blinks in Parkinson’s disease (PD patients during off and on phases of levodopa. Methods Ten PD patients in stages 1 and 2 of the Hoehn & Yahr classification were compared to 18 healthy controls. Artifact-free EEG segments of two seconds preceding the onset of the blink potential were averaged and analyzed, and the statistical significance of the measured amplitudes were evaluated by analysis of variance models. Results The presence of a BP in the PD patients was demonstrated. The mean amplitudes at 0 ms were respectively 0.6 µV and 3.3 µV for the BP patients and the normal controls, respectively. Conclusions The BP amplitudes were significantly smaller in PD patients than normal participants. The amplitudes of the BP were not modified by levodopa.

  12. How Can Students' Academic Performance in Statistics Be Improved? Testing the Influence of Social and Temporal-Self Comparison Feedback in a Web-Based Training Environment

    Science.gov (United States)

    Delaval, Marine; Michinov, Nicolas; Le Bohec, Olivier; Le Hénaff, Benjamin

    2017-01-01

    The aim of this study was to examine how social or temporal-self comparison feedback, delivered in real-time in a web-based training environment, could influence the academic performance of students in a statistics examination. First-year psychology students were given the opportunity to train for a statistics examination during a semester by…

  13. Temporal control of glucocorticoid neurodynamics and its relevance for brain homeostasis, neuropathology and glucocorticoid-based therapeutics.

    Science.gov (United States)

    Kalafatakis, Konstantinos; Russell, Georgina M; Zarros, Apostolos; Lightman, Stafford L

    2016-02-01

    Glucocorticoids mediate plethora of actions throughout the human body. Within the brain, they modulate aspects of immune system and neuroinflammatory processes, interfere with cellular metabolism and viability, interact with systems of neurotransmission and regulate neural rhythms. The influence of glucocorticoids on memory and emotional behaviour is well known and there is increasing evidence for their involvement in many neuropsychiatric pathologies. These effects, which at times can be in opposing directions, depend not only on the concentration of glucocorticoids but also the duration of their presence, the temporal relationship between their fluctuations, the co-influence of other stimuli, and the overall state of brain activity. Moreover, they are region- and cell type-specific. The molecular basis of such diversity of effects lies on the orchestration of the spatiotemporal interplay between glucocorticoid- and mineralocorticoid receptors, and is achieved through complex dynamics, mainly mediated via the circadian and ultradian pattern of glucocorticoid secretion. More sophisticated methodologies are therefore required to better approach the study of these hormones and improve the effectiveness of glucocorticoid-based therapeutics. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. κ-Casein-based hierarchical suprastructures and their use for selective temporal and spatial control over neuronal differentiation.

    Science.gov (United States)

    Chun, Jiyeong; Bhak, Ghibom; Lee, Sang-Gil; Lee, Ji-Hye; Lee, Daekyun; Char, Kookheon; Paik, Seung R

    2012-09-10

    Functions are diversified by producing hierarchical structures from a single raw material. Biologically compatible milk protein of κ-casein has been employed to fabricate higher-order suprastructures. In the presence of dithiothreitol and heat treatment, κ-casein transforms into amyloid fibrils with distinctive morphology attributable to mechanism-based fibrillar polymorphism. As the fibrils elongate to yield high aspect ratio during high-temperature incubation, the resulting fibrils laterally associate into the liquid crystalline state by forming a two-dimensional fibrillar array. Following a desalting process, the fibrillar arrays turn into a three-dimensional matrix of hydrogel that could be selectively disintegrated by subsequent salt treatment. The hydrogel was demonstrated to be a matrix capable of exhibiting controlled release of bioactive substances like retinoic acid, which led to temporal and spatial control over the differentiation of neuronal cells. Therefore, the hierarchical suprastructure formation derived from the single protein of κ-casein producing one-dimensional protein nanofibrils, a two-dimensional liquid crystalline state and a three-dimensional hydrogel could be widely appreciated in various areas of nanobiotechnology including drug delivery and tissue engineering.

  15. Growth process in an elephant tusk: Age estimations based on temporal variations in bomb-radiocarbon content

    Energy Technology Data Exchange (ETDEWEB)

    Nakamura, Toshio, E-mail: nakamura@nendai.nagoya-u.ac.jp [Center for Chronological Research, Nagoya University, Chikusa, Nagoya, Aichi 464-8602 (Japan); Koike, Hiroko [Kyushu University Museum, Kyushu University, Hakozaki, Fukuoka, Fukuoka 814-0180 (Japan); Aizawa, Jun; Okuno, Mitsuru [Department of Earth System Science, Faculty of Science, Fukuoka University, 8-19-1 Nanakuma, Jonan-ku, Fukuoka, Fukuoka 814-0180 (Japan)

    2015-10-15

    In this study, {sup 14}C analysis by accelerator mass spectrometry (AMS) was applied to age estimation based on temporal variations in bomb-produced-{sup 14}C contents of a full elephant tusk registered at Kyushu University. The tusk measured 175 cm long and 13.8 cm in diameter at the root. Thirty tusk-fragment samples were used for {sup 14}C analysis with AMS to estimate the formation ages of different positions according to catalogued global {sup 14}C contents (F{sup 14}C). The F{sup 14}C value of the tip of the tusk suggested that the elephant was born around 1980, while that of the root suggested death around 1994, a lifespan of at least 14 years, rather shorter period than the average lifetime of an elephant (ca. 80 years). In addition, the F{sup 14}C values of fragments collected along a cross-sectional line suggested that the outer part of the tusk formed first with inner parts being deposited gradually with growth.

  16. Temporal-spatial distribution of non-point source pollution in a drinking water source reservoir watershed based on SWAT

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    M. Wang

    2015-05-01

    Full Text Available The conservation of drinking water source reservoirs has a close relationship between regional economic development and people’s livelihood. Research on the non-point pollution characteristics in its watershed is crucial for reservoir security. Tang Pu Reservoir watershed was selected as the study area. The non-point pollution model of Tang Pu Reservoir was established based on the SWAT (Soil and Water Assessment Tool model. The model was adjusted to analyse the temporal-spatial distribution patterns of total nitrogen (TN and total phosphorus (TP. The results showed that the loss of TN and TP in the reservoir watershed were related to precipitation in flood season. And the annual changes showed an "M" shape. It was found that the contribution of loss of TN and TP accounted for 84.5% and 85.3% in high flow years, and for 70.3% and 69.7% in low flow years, respectively. The contributions in normal flow years were 62.9% and 63.3%, respectively. The TN and TP mainly arise from Wangtan town, Gulai town, and Wangyuan town, etc. In addition, it was found that the source of TN and TP showed consistency in space.

  17. Monitoring the brazilian pasturelands: A new mapping approach based on the landsat 8 spectral and temporal domains

    Science.gov (United States)

    Parente, Leandro; Ferreira, Laerte; Faria, Adriano; Nogueira, Sérgio; Araújo, Fernando; Teixeira, Lana; Hagen, Stephen

    2017-10-01

    In a world marked by a rapid population expansion and an unprecedented increase in per capita income and consumption, sustainable food production is certainly the most pressing issue affecting mankind. Within this context, the brazilian pasturelands, the main land-use form in the country, constitute a particularly important asset as a land reserve, which, through improved land-use strategies and intensification, can meet food security goals and contribute to the mitigation of greenhouse gas emissions. In this study, we utilized the entire set of Landsat 8 images available for Brazil in 2015, from which dozens of seasonal metrics were derived, to produce, through objective criteria and automated classification strategies, a new pasture map for the country. Based on the Random Forest algorithm, individually modelled and applied to each one of the 380 Landsat scenes covering the Brazilian territory, our map showed an overall accuracy of 87%. Another result of this study was the thorough spatial and temporal assessment of Landsat 8 data availability in Brazil, which indicated that about 80% of the country had 12 or fewer observations free of clouds or cloud shadows in 2015.

  18. Object-Based Greenhouse Horticultural Crop Identification from Multi-Temporal Satellite Imagery: A Case Study in Almeria, Spain

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    Manuel A. Aguilar

    2015-06-01

    Full Text Available Greenhouse detection and mapping via remote sensing is a complex task, which has already been addressed in numerous studies. In this research, the innovative goal relies on the identification of greenhouse horticultural crops that were growing under plastic coverings on 30 September 2013. To this end, object-based image analysis (OBIA and a decision tree classifier (DT were applied to a set consisting of eight Landsat 8 OLI images collected from May to November 2013. Moreover, a single WorldView-2 satellite image acquired on 30 September 2013, was also used as a data source. In this approach, basic spectral information, textural features and several vegetation indices (VIs derived from Landsat 8 and WorldView-2 multi-temporal satellite data were computed on previously segmented image objects in order to identify four of the most popular autumn crops cultivated under greenhouse in Almería, Spain (i.e., tomato, pepper, cucumber and aubergine. The best classification accuracy (81.3% overall accuracy was achieved by using the full set of Landsat 8 time series. These results were considered good in the case of tomato and pepper crops, being significantly worse for cucumber and aubergine. These results were hardly improved by adding the information of the WorldView-2 image. The most important information for correct classification of different crops under greenhouses was related to the greenhouse management practices and not the spectral properties of the crops themselves.

  19. ERK and phosphoinositide 3-kinase temporally coordinate different modes of actin-based motility during embryonic wound healing

    Science.gov (United States)

    Li, Jingjing; Zhang, Siwei; Soto, Ximena; Woolner, Sarah; Amaya, Enrique

    2013-01-01

    Summary Embryonic wound healing provides a perfect example of efficient recovery of tissue integrity and homeostasis, which is vital for survival. Tissue movement in embryonic wound healing requires two functionally distinct actin structures: a contractile actomyosin cable and actin protrusions at the leading edge. Here, we report that the discrete formation and function of these two structures is achieved by the temporal segregation of two intracellular upstream signals and distinct downstream targets. The sequential activation of ERK and phosphoinositide 3-kinase (PI3K) signalling divides Xenopus embryonic wound healing into two phases. In the first phase, activated ERK suppresses PI3K activity, and is responsible for the activation of Rho and myosin-2, which drives actomyosin cable formation and constriction. The second phase is dominated by restored PI3K signalling, which enhances Rac and Cdc42 activity, leading to the formation of actin protrusions that drive migration and zippering. These findings reveal a new mechanism for coordinating different modes of actin-based motility in a complex tissue setting, namely embryonic wound healing. PMID:23986484

  20. Remote Sensing-Based Biomass Estimation and Its Spatio-Temporal Variations in Temperate Grassland, Northern China

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    Yunxiang Jin

    2014-02-01

    Full Text Available Grassland biomass is essential for maintaining grassland ecosystems. Moreover, biomass is an important characteristic of grassland. In this study, we combined field sampling with remote sensing data and calculated five vegetation indices (VIs. Using this combined information, we quantified a remote sensing estimation model and estimated biomass in a temperate grassland of northern China. We also explored the dynamic spatio-temporal variation of biomass from 2006 to 2012. Our results indicated that all VIs investigated in the study were strongly correlated with biomass (α < 0.01. The precision of the model for estimating biomass based on ground data and remote sensing was greater than 73%. Additionally, the results of our analysis indicated that the annual average biomass was 11.86 million tons and that the average yield was 604.5 kg/ha. The distribution of biomass exhibited substantial spatial heterogeneity, and the biomass decreased from the eastern portion of the study area to the western portion. The interannual biomass exhibited strong fluctuations during 2006–2012, with a coefficient of variation of 26.95%. The coefficient of variation of biomass differed among the grassland types. The highest coefficient of variation was found for the desert steppe, followed by the typical steppe and the meadow steppe.

  1. Detection of EEG spatial-spectral-temporal signatures of errors: a comparative study of ICA-based and channel-based methods.

    Science.gov (United States)

    Shou, Guofa; Ding, Lei

    2015-01-01

    The present study aimed to investigate the sensitivity of independent component analysis (ICA)- and channel-based methods in detecting electroencephalography (EEG) spatial-spectral-temporal signatures of performance errors. 128-channel EEG signals recorded from 18 subjects, who performed a color-word matching Stroop task, were analyzed. The spatial-spectral-temporal patterns in event-related potentials (ERPs) and oscillatory activities (i.e., power and phase) were measured at four selected channels, i.e., FCz, Pz, O1 and O2, from original EEG data after preprocessing, EEG data after additional current source density (CSD) transform, and back-projected EEG data from individual ICs after additional ICA analysis. Pair-wise correlation coefficient (CC) and mutual information (MI), calculated from three EEG data at four selected channels, were compared to examine mutual correlations in EEG signals obtained through three different means. Thereafter, EEG signatures of errors from these three means were statistically compared at multiple time windows in the contrast of error and correct responses. Significantly decreased CC and MI values were observed in CSD- and ICA-processed EEGs as compared with original EEG, with the smallest CC and MI in ICA EEG. Similar error patterns in ERPs and peri-response oscillatory activities were detected in all three EEGs, whereas the pre-stimulus and post-stimulus error-related oscillatory patterns identified in ICA EEG were either not or only partially detected in both original EEG and CSD EEGs in general. Both CSD and ICA processes can largely reduce signal correlations due to the volume conduction effect in original EEG, and EEG signatures of errors are better detected by ICA-based method than channel-based method (i.e., original and CSD EEGs). ICA provides the best sensitivity to detect EEG signatures linked to specific neural processes via disentangling superimposed channel-level EEG signals into distinct neurocognitive process

  2. Temporal evolution of two auroral arcs as measured by the Cluster satellite and coordinated ground-based instruments

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    A. T. Aikio

    2004-12-01

    Full Text Available The four Cluster s/c passed over Northern Scandinavia on 6 February 2001 from south-east to north-west at a radial distance of about 4.4 RE in the post-midnight sector. When mapped along geomagnetic field lines, the separation of the spacecraft in the ionosphere was confined to within 110km in latitude and 50km in longitude. This constellation allowed us to study the temporal evolution of plasma with a time scale of a few minutes. Ground-based instrumentation used involved two all-sky cameras, magnetometers and the EISCAT radar. The main findings were as follows.

    Two auroral arcs were located close to the equatorward and poleward edge of a large-scale density cavity, respectively. These arcs showed a different kind of a temporal evolution. (1 As a response to a pseudo-breakup onset, both the up- and downward field-aligned current (FAC sheets associated with the equatorward arc widened and the total amount of FAC doubled in a time scale of 1–2min. (2 In the poleward arc, a density cavity formed in the ionosphere in the return (downward current region. As a result of ionospheric feedback, a strongly enhanced ionospheric southward electric field developed in the region of decreased Pedersen conductance. Furthermore, the acceleration potential of ionospheric electrons, carrying the return current, increased from 200 to 1000eV in 70s, and the return current region widened in order to supply a constant amount of return current to the arc current circuit.

    Evidence of local acceleration of the electron population by dispersive Alfvén waves was obtained in the upward FAC region of the poleward arc. However, the downward accelerated suprathermal electrons must be further energised below Cluster in order to be able to produce the observed visible aurora.

    Both of the auroral arcs were associated with broad-band ULF/ELF (BBELF waves

  3. Temporal evolution of two auroral arcs as measured by the Cluster satellite and coordinated ground-based instruments

    Directory of Open Access Journals (Sweden)

    A. T. Aikio

    2004-12-01

    Full Text Available The four Cluster s/c passed over Northern Scandinavia on 6 February 2001 from south-east to north-west at a radial distance of about 4.4 RE in the post-midnight sector. When mapped along geomagnetic field lines, the separation of the spacecraft in the ionosphere was confined to within 110km in latitude and 50km in longitude. This constellation allowed us to study the temporal evolution of plasma with a time scale of a few minutes. Ground-based instrumentation used involved two all-sky cameras, magnetometers and the EISCAT radar. The main findings were as follows. Two auroral arcs were located close to the equatorward and poleward edge of a large-scale density cavity, respectively. These arcs showed a different kind of a temporal evolution. (1 As a response to a pseudo-breakup onset, both the up- and downward field-aligned current (FAC sheets associated with the equatorward arc widened and the total amount of FAC doubled in a time scale of 1–2min. (2 In the poleward arc, a density cavity formed in the ionosphere in the return (downward current region. As a result of ionospheric feedback, a strongly enhanced ionospheric southward electric field developed in the region of decreased Pedersen conductance. Furthermore, the acceleration potential of ionospheric electrons, carrying the return current, increased from 200 to 1000eV in 70s, and the return current region widened in order to supply a constant amount of return current to the arc current circuit. Evidence of local acceleration of the electron population by dispersive Alfvén waves was obtained in the upward FAC region of the poleward arc. However, the downward accelerated suprathermal electrons must be further energised below Cluster in order to be able to produce the observed visible aurora. Both of the auroral arcs were associated with broad-band ULF/ELF (BBELF waves, but they were highly localised in space and time. The most intense BBELF waves were confined typically to the return

  4. Management of middle meningeal and superficial temporal artery hemorrhage from total temporomandibular joint replacement surgery with a gelatin-based hemostatic agent.

    Science.gov (United States)

    Cillo, Joseph E; Sinn, Douglas; Truelson, John M

    2005-03-01

    Complications associated with temporomandibular joint (TMJ) replacement surgery may include injury to nerves, blood vessels, and otologic structures. Vascular injuries can be associated with trauma to the carotid artery and its terminal branches, the superficial temporal artery, and the internal maxillary artery. Suggested management to control hemorrhage has included uniand bipolar electrocautery, laser ablation, local anesthetics with vasoconstrictors, direct pressure, embolization, and ligation. In this case report, the iatrogenic injury to both the middle meningeal and superficial temporal arteries during total TMJ replacement surgery controlled by using a gelatin-based hemostatic agent is discussed.

  5. Spatio-temporal analysis of SAR based time series for slope instability characterization: the Corvara in Badia landslide (Dolomites, Italy)

    Science.gov (United States)

    Mulas, M.; Petitta, M.; Brazanti, M.; Benedetti, E.; Corsini, A.; Iasio, C.

    2012-04-01

    The aim of this study is to estimate the influence of different forcing factors acting on instability phases of a slow alpine earthslide-earthflow, by means of the characteristics of decomposed deformations signals derived by displacement rates measured in its different sectors. In this work we analyze a slow landslide located ESE from Corvara in Badia, a famous tourist area in the Dolomites (NE Italy). Road, infrastructure, ski and other recreational facilities, isolated buildings close to the town of Corvara and finally an artificial reservoir for snow production are threatened and occasionally damaged by this mass movement. It flows from 2000m s.l. to 1500m s.l. where a paleo-landslide deposit is partially covered and re-activated. In the last 10 years the Province of Bolzano carried out discontinuous GPS surveys between 5 and 1 times per year to define the landslide's level of hazard. The landslide volume is resulted to be 30Mm3, extending downslope for approx. 3km, with displacement rates between few centimeters and slightly less than 10m per year. To analyze this area we used data from active radar sensors (SAR - Synthetic Aperture Radar). The SAR-based dataset consists in high resolution X-band SAR data from the Cosmo SkyMed (CSK) mission acquired every 8 days from August 2010 to September 2011. Part of the 38 CSK scenes contain the back-scattering signal from 17 artificial reflectors (AR) installed along the AOI and partially on existing GPS benchmarks for data validation and integration. The ARs back scattering signal has been elaborated in order to track their displacement from August 2010 to September 2011, in the lower zone of the landslide, as well as from March 2011 to September 2011 in the higher part, excluding the period when the snow was covering the surface. The signals have been analyzed with Fourier and wavelet methods to identify the different frequencies and nature of the components. T and Mann-Kendall tests have been used to assess the

  6. Substantial Equivalence Standards in Tobacco Governance: Statutory Clarity and Regulatory Precedent for the FSPTCA.

    Science.gov (United States)

    Carpenter, Daniel; Connolly, Gregory N; Lempert, Lauren Kass

    2017-08-01

    The Family Smoking Prevention and Tobacco Control Act (FSPTCA) of 2009 creates the first national system of premarket regulation of tobacco products in American history. The FDA must now review and give marketing authorization to all new tobacco products, based on a public health standard, before they can be legally marketed. Yet the law also contains an alternative pathway for market entry-the substantial equivalence (SE) clause-by which novel and altered tobacco products can be marketed by demonstrating their substantial equivalence to existing products. Over 99 percent of tobacco product applications sent to the FDA under the new law have used this mechanism, and loose application of the SE mechanism carries the risk of undoing the FDA's gatekeeping power under the law. We review the statutory and regulatory precedent for SE, examining the FSPTCA itself as well as regulatory precedent from drug and device regulation (from which the term substantial equivalence and much of the associated statutory language was derived). Our review of standards and scientific precedent demonstrates that exacting scrutiny under the public health standard should govern all SE reviews and that clinical data incorporating social scientific evidence should be routinely required for SE claims by tobacco product sponsors. Copyright © 2017 by Duke University Press.

  7. Sleeping Pattern of Medical Students Preceding Viva Examination and Their Performance.

    Science.gov (United States)

    Ansari, M

    2015-01-01

    Sleep is an important determinant of keeping healthy physically and mentally. Deviation in sleep is a common problem among students during examinations. The purpose of this study is to determine students' sleep pattern during night preceding viva examination and its correlation with performance. This was a cross-sectional prospective study conducted between January and February 2014 among 1st and 2nd year MBBS students of National Medical College, Birgunj, Nepal who appeared in University's final practical examinations. Based on simple random sampling approach, each of the 280 participants was allowed to pick out five pieces of lottery papers and they were asked the five questions resembling the number in the list of questions. Among the total 280 students, 74.6% were from India and 25.4% were from Nepal, and majorities (63%) of them were males. Fifty two percent of the students either could not sleep at all or slept just for 1 to 1.5 hours while 12% slept for 5 to 6.5 hours. Two-third (66%) of the students was able enough to achieve one to two scores, and only 1.8% could succeed to get the maximum score of five. The correlation between hours of sleep preceding examination and the score achieved was positively (r=0.701) and statistically significantly correlated (pstudents either not to sleep or sleep only for few hours preceding viva examination that result in poor performance in examinations.

  8. Quality assessment of static aggregation compared to the temporal approach based on a pig trade network in Northern Germany.

    Science.gov (United States)

    Büttner, Kathrin; Salau, Jennifer; Krieter, Joachim

    2016-07-01

    Recent analyses of animal movement networks focused on the static aggregation of trade contacts over different time windows, which neglects the system's temporal variation. In terms of disease spread, ignoring the temporal dynamics can lead to an over- or underestimation of an outbreak's speed and extent. This becomes particularly evident, if the static aggregation allows for the existence of more paths compared to the number of time-respecting paths (i.e. paths in the right chronological order). Therefore, the aim of this study was to reveal differences between static and temporal representations of an animal trade network and to assess the quality of the static aggregation in comparison to the temporal counterpart. Contact data from a pig trade network (2006-2009) of a producer community in Northern Germany were analysed. The results show that a median value of 8.7 % (4.6-14.1%) of the nodes and 3.1% (1.6-5.5%) of the edges were active on a weekly resolution. No fluctuations in the activity patterns were obvious. Furthermore, 50% of the nodes already had one trade contact after approximately six months. For an accumulation window with increasing size (one day each), the accumulation rate, i.e. the relative increase in the number of nodes or edges, stayed relatively constant below 0.07% for the nodes and 0.12 % for the edges. The temporal distances had a much wider distribution than the topological distances. 84% of the temporal distances were smaller than 90 days. The maximum temporal distance was 1000 days, which corresponds to the temporal diameter of the present network. The median temporal correlation coefficient, which measures the probability for an edge to persist across two consecutive time steps, was 0.47, with a maximum value of 0.63 at the accumulation window of 88 days. The causal fidelity measures the fraction of the number of static paths which can also be taken in the temporal network. For the whole observation period relatively high values

  9. Object-Based Paddy Rice Mapping Using HJ-1A/B Data and Temporal Features Extracted from Time Series MODIS NDVI Data.

    Science.gov (United States)

    Singha, Mrinal; Wu, Bingfang; Zhang, Miao

    2016-12-22

    Accurate and timely mapping of paddy rice is vital for food security and environmental sustainability. This study evaluates the utility of temporal features extracted from coarse resolution data for object-based paddy rice classification of fine resolution data. The coarse resolution vegetation index data is first fused with the fine resolution data to generate the time series fine resolution data. Temporal features are extracted from the fused data and added with the multi-spectral data to improve the classification accuracy. Temporal features provided the crop growth information, while multi-spectral data provided the pattern variation of paddy rice. The achieved overall classification accuracy and kappa coefficient were 84.37% and 0.68, respectively. The results indicate that the use of temporal features improved the overall classification accuracy of a single-date multi-spectral image by 18.75% from 65.62% to 84.37%. The minimum sensitivity (MS) of the paddy rice classification has also been improved. The comparison showed that the mapped paddy area was analogous to the agricultural statistics at the district level. This work also highlighted the importance of feature selection to achieve higher classification accuracies. These results demonstrate the potential of the combined use of temporal and spectral features for accurate paddy rice classification.

  10. A Novel Spatial-Temporal Voronoi Diagram-Based Heuristic Approach for Large-Scale Vehicle Routing Optimization with Time Constraints

    Directory of Open Access Journals (Sweden)

    Wei Tu

    2015-10-01

    Full Text Available Vehicle routing optimization (VRO designs the best routes to reduce travel cost, energy consumption, and carbon emission. Due to non-deterministic polynomial-time hard (NP-hard complexity, many VROs involved in real-world applications require too much computing effort. Shortening computing time for VRO is a great challenge for state-of-the-art spatial optimization algorithms. From a spatial-temporal perspective, this paper presents a spatial-temporal Voronoi diagram-based heuristic approach for large-scale vehicle routing problems with time windows (VRPTW. Considering time constraints, a spatial-temporal Voronoi distance is derived from the spatial-temporal Voronoi diagram to find near neighbors in the space-time searching context. A Voronoi distance decay strategy that integrates a time warp operation is proposed to accelerate local search procedures. A spatial-temporal feature-guided search is developed to improve unpromising micro route structures. Experiments on VRPTW benchmarks and real-world instances are conducted to verify performance. The results demonstrate that the proposed approach is competitive with state-of-the-art heuristics and achieves high-quality solutions for large-scale instances of VRPTWs in a short time. This novel approach will contribute to spatial decision support community by developing an effective vehicle routing optimization method for large transportation applications in both public and private sectors.

  11. Temporal dynamics of frequency-tunable graphene-based plasmonic grating structures for ultra-broadband terahertz communication

    Science.gov (United States)

    Jornet, Josep Miquel; Thawdar, Ngwe; Woo, Ethan; Andrello, Michael A.

    2017-05-01

    Terahertz (THz) communication is envisioned as a key wireless technology to satisfy the need for 1000x faster wireless data rates. To date, major progress on both electronic and photonic technologies are finally closing the so-called THz gap. Among others, graphene-based plasmonic nano-devices have been proposed as a way to enable ultra-broadband communications above 1THz. The unique dynamic complex conductivity of graphene enables the propagation of Surface Plasmon Polariton (SPP) waves at THz frequencies. In addition, the conductivity of graphene and, thus, the SPP propagation properties, can be dynamically tuned by means of electrostatic biasing or material doping. This result opens the door to frequency-tunable devices for THz communications. In this paper, the temporal dynamics of graphene-enhanced metallic grating structures used for excitation and detection of SPP waves at THz frequencies are analytically and numerically modeled. More specifically, the response of a metallic grating structure built on top of a graphene-based heterostructure is analyzed by taking into account the grating period and duty cycle and the Fermi energy of the graphene layer. Then, the interfacial charge transfer between a metallic back-gate and the graphene layer in a metal/dielectric/graphene stack is analytically modeled, and the range of achievable Fermi energies is determined. Finally, the rate at which the Fermi energy in graphene can be tuned is estimated starting from the transmission line model of graphene. Extensive numerical and simulation results with COMSOL Multi-physics are provided. The results show that the proposed structure enables dynamic frequency systems with THz bandwidths, thus, enabling resilient communication techniques such as time-hopping THz modulations.

  12. Spatio-Temporal Super-Resolution Reconstruction of Remote-Sensing Images Based on Adaptive Multi-Scale Detail Enhancement.

    Science.gov (United States)

    Zhu, Hong; Tang, Xinming; Xie, Junfeng; Song, Weidong; Mo, Fan; Gao, Xiaoming

    2018-02-07

    There are many problems in existing reconstruction-based super-resolution algorithms, such as the lack of texture-feature representation and of high-frequency details. Multi-scale detail enhancement can produce more texture information and high-frequency information. Therefore, super-resolution reconstruction of remote-sensing images based on adaptive multi-scale detail enhancement (AMDE-SR) is proposed in this paper. First, the information entropy of each remote-sensing image is calculated, and the image with the maximum entropy value is regarded as the reference image. Subsequently, spatio-temporal remote-sensing images are processed using phase normalization, which is to reduce the time phase difference of image data and enhance the complementarity of information. The multi-scale image information is then decomposed using the L ₀ gradient minimization model, and the non-redundant information is processed by difference calculation and expanding non-redundant layers and the redundant layer by the iterative back-projection (IBP) technique. The different-scale non-redundant information is adaptive-weighted and fused using cross-entropy. Finally, a nonlinear texture-detail-enhancement function is built to improve the scope of small details, and the peak signal-to-noise ratio (PSNR) is used as an iterative constraint. Ultimately, high-resolution remote-sensing images with abundant texture information are obtained by iterative optimization. Real results show an average gain in entropy of up to 0.42 dB for an up-scaling of 2 and a significant promotion gain in enhancement measure evaluation for an up-scaling of 2. The experimental results show that the performance of the AMED-SR method is better than existing super-resolution reconstruction methods in terms of visual and accuracy improvements.

  13. Spatio-temporal characteristics of livestock and their effects on pollution in China based on geographic information system.

    Science.gov (United States)

    Liu, Ruimin; Xu, Fei; Liu, Yongyan; Wang, Jiawei; Yu, Wenwen

    2016-07-01

    Livestock pollution, caused by rural household's scatter breeding mainly, is one of the major non-point sources. Different animal manures are abundant with different nutrients. Adopting the policies, management practices, and technologies related to livestock production based on livestock structure analysis can improve the efficiency on preventing pollution. Based on statistical data, the component structure of livestock was analyzed and corresponding effect on pollution was evaluated during the period of 1992-2012 in China. The results showed that the average annual growth rate (AAGR) of total China was 1.58 % during the 20 years. Larger amounts of livestock were concentrated in Southwest China and East China. In the view of component structure, each type of livestock had different distribution characteristics and constant increasing amounts were presented during the 20 years. Cattle took the largest proportion in almost every province, and the number of heads was over 40 % of all the livestock quantity for most provinces. Pollution of total nitrogen (TN), total phosphorus (TP), and chemical oxygen demand (COD) caused by livestock excretion in East and Southeast China was much more serious than that in other regions. However, the load of COD was far less than that of TN and TP. Cattle accounted most for the livestock pollution, and swine was the second one. The intensity characteristics of TN, TP, and COD were different from that of total pollution loads. The spatio-temporal characteristics of amounts and component structure of livestock were influenced by three kinds of factors (natural, economic, and social), such as climate, topography, modes of production, feed grain sector, related policies, and area of the study regions. Different livestock excrements had different impacts on environment. According to various livestock structures and economy conditions, different disposal methods should be adopted.

  14. Baseline activity predicts working memory load of preceding task condition.

    Science.gov (United States)

    Pyka, Martin; Hahn, Tim; Heider, Dominik; Krug, Axel; Sommer, Jens; Kircher, Tilo; Jansen, Andreas

    2013-11-01

    The conceptual notion of the so-called resting state of the brain has been recently challenged by studies indicating a continuing effect of cognitive processes on subsequent rest. In particular, activity in posterior parietal and medial prefrontal areas has been found to be modulated by preceding experimental conditions. In this study, we investigated which brain areas show working memory dependent patterns in subsequent baseline periods and how specific they are for the preceding experimental condition. During functional magnetic resonance imaging, 94 subjects performed a letter-version of the n-back task with the conditions 0-back and 2-back followed by a low-level baseline in which subjects had to passively observe the letters appearing. In a univariate analysis, 2-back served as control condition while 0-back, baseline after 0-back and baseline after 2-back were modeled as regressors to test for activity changes between both baseline conditions. Additionally, we tested, using Gaussian process classifiers, the recognition of task condition from functional images acquired during baseline. Besides the expected activity changes in the precuneus and medial prefrontal cortex, we found differential activity in the thalamus, putamen, and postcentral gyrus that were affected by the preceding task. The multivariate analysis revealed that images of the subsequent baseline block contain task related patterns that yield a recognition rate of 70%. The results suggest that the influence of a cognitive task on subsequent baseline is strong and specific for some areas but not restricted to areas of the so-called default mode network. Copyright © 2012 Wiley Periodicals, Inc.

  15. Visual working memory deterioration preceding relapse in psychosis.

    Science.gov (United States)

    Hui, C L M; Li, Y K; Li, A W Y; Lee, E H M; Chang, W C; Chan, S K W; Lam, S Y; Thornton, A E; Sham, P; Honer, W G; Chen, E Y H

    2016-08-01

    Relapse is distressingly common after the first episode of psychosis, yet it is poorly understood and difficult to predict. Investigating changes in cognitive function preceding relapse may provide new insights into the underlying mechanism of relapse in psychosis. We hypothesized that relapse in fully remitted first-episode psychosis patients was preceded by working memory deterioration. Visual memory and verbal working memory were monitored prospectively in a 1-year randomized controlled trial of remitted first-episode psychosis patients assigned to medication continuation (quetiapine 400 mg/day) or discontinuation (placebo). Relapse (recurrence of positive symptoms of psychosis), visual (Visual Patterns Test) and verbal (Letter-Number span test) working memory and stressful life events were assessed monthly. Remitted first-episode patients (n = 102) participated in the study. Relapsers (n = 53) and non-relapsers (n = 49) had similar baseline demographic and clinical profiles. Logistic regression analyses indicated relapse was associated with visual working memory deterioration 2 months before relapse [odds ratio (OR) 3.07, 95% confidence interval (CI) 1.19-7.92, P = 0.02], more stressful life events 1 month before relapse (OR 2.11, 95% CI 1.20-3.72, P = 0.01) and medication discontinuation (OR 5.52, 95% CI 2.08-14.62, P = 0.001). Visual working memory deterioration beginning 2 months before relapse in remitted first-episode psychosis patients (not baseline predictor) may reflect early brain dysfunction that heralds a psychotic relapse. The deterioration was found to be unrelated to a worsening of psychotic symptoms preceding relapse. Testable predictors offer insight into the brain processes underlying relapse in psychosis.

  16. USING PRECEDENTS FOR REDUCTION OF DECISION TREE BY GRAPH SEARCH

    Directory of Open Access Journals (Sweden)

    I. A. Bessmertny

    2015-01-01

    Full Text Available The paper considers the problem of mutual payment organization between business entities by means of clearing that is solved by search of graph paths. To reduce the decision tree complexity a method of precedents is proposed that consists in saving the intermediate solution during the moving along decision tree. An algorithm and example are presented demonstrating solution complexity coming close to a linear one. The tests carried out in civil aviation settlement system demonstrate approximately 30 percent shortage of real money transfer. The proposed algorithm is planned to be implemented also in other clearing organizations of the Russian Federation.

  17. Design of a Secure RFID Authentication Scheme Preceding Market Transactions

    Directory of Open Access Journals (Sweden)

    Chin-Ling Chen

    2011-01-01

    Full Text Available In recent years, as RFID reader equipment is ever more widely deployed in handled devices, the importance of security problems among RFID reader, tags and server have obviously gained increased attention. However, there are still many security issues preceding transactions; these issues are well worth discussing. In this paper, we propose a novel authentication scheme, conforming EPC C1G2 standards, at a low implementation cost for market application. In order to achieve mutual authentication, the proposed scheme integrates fingerprint biometrics, related cryptology and a hash function mechanism to ensure the security of the transmitted messages. The proposed scheme also can resist known attacks.

  18. Spatio-Temporal Rule Mining

    DEFF Research Database (Denmark)

    Gidofalvi, Gyozo; Pedersen, Torben Bach

    2005-01-01

    Recent advances in communication and information technology, such as the increasing accuracy of GPS technology and the miniaturization of wireless communication devices pave the road for Location-Based Services (LBS). To achieve high quality for such services, spatio-temporal data mining techniques...... are needed. In this paper, we describe experiences with spatio-temporal rule mining in a Danish data mining company. First, a number of real world spatio-temporal data sets are described, leading to a taxonomy of spatio-temporal data. Second, the paper describes a general methodology that transforms...... the spatio-temporal rule mining task to the traditional market basket analysis task and applies it to the described data sets, enabling traditional association rule mining methods to discover spatio-temporal rules for LBS. Finally, unique issues in spatio-temporal rule mining are identified and discussed....

  19. Retrieval and spatial-temporal analysis of aerosol in Sichuan province based on multi-source remote sensing

    Science.gov (United States)

    Liu, Zhihong; Liu, Hu; Zhang, Yang; Ge, Ying

    2015-04-01

    Sichuan Basin is one of the serious haze regions in China. It has great significance to monitor the atmospheric haze in Sichuan Basin. In this study, MOD04 product , OMI-NO2 product and OMI-SO2 product were used to analysis the spatial and temporal distribution characteristic of atmospheric pollutants in Sichuan from year 2008 to 2012. Micro pulse lidar (MPL) and HJ-1 satellites were used to retrieve the aerosol extinction coefficient and aerosol optical depth (AOD). Also we established a linear relationship between the AOD and PM10. The MOD04 data showed that the AOD in west Sichuan plateau was relatively low. The annual AOD-average in the regions such as Kangding, Maerkang, Xichang and Yaan was about 0.2. The Sichuan Basin such as Chengdu, Deyang, Mianyang has relatively higher annual AOD-average which was about 0.8 to 1.0, and it had obvious seasonal change feature. The spatial and temporal distribution of aerosol optical depth in Chendu showed obvious urban characteristics. These characteristics are related to the industrial situation, the location and the climate condition of Sichuan. Year 2011 has this highest annual AOD-average value. The OMI-NO2 product showed that the distribution characteristic of NO2 in Sichuan was similar with aerosol. The NO2 concentration was about 0.7 molec/cm2 in west Sichuan plateau and greater than 4.2 molec/cm2 in Chengdu, Deyang, Mianyang. However, the SO2 distribution characteristic was slightly different. The SO2 concentration was low in west Sichuan plateau with an annual average concentration of 0.2 DU. Zigong, Yibin, Luzhou were the main high value areas with an annual average concentration of 1.1 DU. Fernald method was used to retrieve the aerosol extinction coefficient based on the MPL. The result showed that the daily maximum was appeared about 07:00 am and the highest aerosol extinction coefficient season was winter. The aerosol extinction coefficient was higher below the altitude of 300 m. Based on the data of HJ-1

  20. Functional connectivity of the hippocampus in temporal lobe epilepsy: feasibility of a task-regressed seed-based approach.

    Science.gov (United States)

    Kucukboyaci, Nuri Erkut; Kemmotsu, Nobuko; Cheng, Chris E; Girard, Holly M; Tecoma, Evelyn S; Iragui, Vicente J; McDonald, Carrie R

    2013-01-01

    Resting-state functional connectivity (FC) has revealed marked network dysfunction in patients with temporal lobe epilepsy (TLE) compared to healthy controls. However, the nature and the location of these changes have not been fully elucidated nor confirmed by other methodologies. We assessed the presence of hippocampal FC changes in TLE based on the low frequency residuals of task-related functional magnetic resonance imaging data after the removal of task-related activation [i.e., task-regressed functional connectivity MRI (fcMRI)]. We employed a novel, task-regressed approach to quantify hippocampal FC, and compare hippocampal FC in 17 patients with unilateral TLE (9 left) with 17 healthy controls. Our results suggest widespread FC reductions in the mesial cortex associated with the default mode network (DMN), and some local FC increases in the lateral portions of the right hemisphere. We found more pronounced FC decreases in the left hemisphere than in the right, and these FC decreases were greatest in patients with left TLE. Moreover, the FC reductions observed between the hippocampus and posterior cingulate, inferior parietal, paracentral regions are in agreement with previous resting state studies. Consistent with the existing literature, FC reductions in TLE appear widespread with prominent reductions in the medial portion of the DMN. Our data expand the literature by demonstrating that reductions in FC may be greatest in the left hemisphere and in patients with left TLE. Overall, our findings suggest that task-regressed FC is a viable alternative to resting state and that future studies may extract similar information on network connectivity from already existing datasets.

  1. Responses in the right posterior superior temporal sulcus show a feature-based response to facial expression.

    Science.gov (United States)

    Flack, Tessa R; Andrews, Timothy J; Hymers, Mark; Al-Mosaiwi, Mohammed; Marsden, Samuel P; Strachan, James W A; Trakulpipat, Chayanit; Wang, Liang; Wu, Tian; Young, Andrew W

    2015-08-01

    The face-selective region of the right posterior superior temporal sulcus (pSTS) plays an important role in analysing facial expressions. However, it is less clear how facial expressions are represented in this region. In this study, we used the face composite effect to explore whether the pSTS contains a holistic or feature-based representation of facial expression. Aligned and misaligned composite images were created from the top and bottom halves of faces posing different expressions. In Experiment 1, participants performed a behavioural matching task in which they judged whether the top half of two images was the same or different. The ability to discriminate the top half of the face was affected by changes in the bottom half of the face when the images were aligned, but not when they were misaligned. This shows a holistic behavioural response to expression. In Experiment 2, we used fMR-adaptation to ask whether the pSTS has a corresponding holistic neural representation of expression. Aligned or misaligned images were presented in blocks that involved repeating the same image or in which the top or bottom half of the images changed. Increased neural responses were found in the right pSTS regardless of whether the change occurred in the top or bottom of the image, showing that changes in expression were detected across all parts of the face. However, in contrast to the behavioural data, the pattern did not differ between aligned and misaligned stimuli. This suggests that the pSTS does not encode facial expressions holistically. In contrast to the pSTS, a holistic pattern of response to facial expression was found in the right inferior frontal gyrus (IFG). Together, these results suggest that pSTS reflects an early stage in the processing of facial expression in which facial features are represented independently. Copyright © 2015 Elsevier Ltd. All rights reserved.

  2. Temporal network based analysis of cell specific vein graft transcriptome defines key pathways and hub genes in implantation injury.

    Directory of Open Access Journals (Sweden)

    Manoj Bhasin

    Full Text Available Vein graft failure occurs between 1 and 6 months after implantation due to obstructive intimal hyperplasia, related in part to implantation injury. The cell-specific and temporal response of the transcriptome to vein graft implantation injury was determined by transcriptional profiling of laser capture microdissected endothelial cells (EC and medial smooth muscle cells (SMC from canine vein grafts, 2 hours (H to 30 days (D following surgery. Our results demonstrate a robust genomic response beginning at 2 H, peaking at 12-24 H, declining by 7 D, and resolving by 30 D. Gene ontology and pathway analyses of differentially expressed genes indicated that implantation injury affects inflammatory and immune responses, apoptosis, mitosis, and extracellular matrix reorganization in both cell types. Through backpropagation an integrated network was built, starting with genes differentially expressed at 30 D, followed by adding upstream interactive genes from each prior time-point. This identified significant enrichment of IL-6, IL-8, NF-κB, dendritic cell maturation, glucocorticoid receptor, and Triggering Receptor Expressed on Myeloid Cells (TREM-1 signaling, as well as PPARα activation pathways in graft EC and SMC. Interactive network-based analyses identified IL-6, IL-8, IL-1α, and Insulin Receptor (INSR as focus hub genes within these pathways. Real-time PCR was used for the validation of two of these genes: IL-6 and IL-8, in addition to Collagen 11A1 (COL11A1, a cornerstone of the backpropagation. In conclusion, these results establish causality relationships clarifying the pathogenesis of vein graft implantation injury, and identifying novel targets for its prevention.

  3. Evaluating spatial-temporal dynamics of net primary productivity of different forest types in northeastern China based on improved FORCCHN.

    Directory of Open Access Journals (Sweden)

    Junfang Zhao

    Full Text Available An improved individual-based forest ecosystem carbon budget model for China (FORCCHN was applied to investigate the spatial-temporal dynamics of net primary productivity of different forest types in northeastern China. In this study, the forests of northeastern China were categorized into four ecological types according to their habitats and generic characteristics (evergreen broadleaf forest, deciduous broadleaf forest, evergreen needleleaf forest and deciduous needleleaf forest. The results showed that distribution and change of forest NPP in northeastern China were related to the different forest types. From 1981 to 2002, among the forest types in northeastern China, per unit area NPP and total NPP of deciduous broadleaf forest were the highest, with the values of 729.4 gC/(m(2•yr and 106.0 TgC/yr, respectively, followed by mixed broadleaf- needleleaf forest, deciduous needleleaf forest and evergreen needleleaf forest. From 1981 to 2002, per unit area NPP and total NPP of different forest types in northeastern China exhibited significant trends of interannual increase, and rapid increase was found between the 1980s and 1990s. The contribution of the different forest type's NPP to total NPP in northeastern China was clearly different. The greatest was deciduous broadleaf forest, followed by mixed broadleaf- needleleaf forest and deciduous needleleaf forest. The smallest was evergreen needleleaf forest. Spatial difference in NPP between different forest types was remarkable. High NPP values of deciduous needleleaf forest, mixed broadleaf- needleleaf forest and deciduous broadleaf forest were found in the Daxing'anling region, the southeastern of Xiaoxing'anling and Jilin province, and the Changbai Mountain, respectively. However, no regional differences were found for evergreen needleleaf NPP. This study provided not only an estimation NPP of different forest types in northeastern China but also a useful methodology for estimating forest

  4. An Efficient Method of Sharing Mass Spatio-Temporal Trajectory Data Based on Cloudera Impala for Traffic Distribution Mapping in an Urban City

    Directory of Open Access Journals (Sweden)

    Lianjie Zhou

    2016-10-01

    Full Text Available The efficient sharing of spatio-temporal trajectory data is important to understand traffic congestion in mass data. However, the data volumes of bus networks in urban cities are growing rapidly, reaching daily volumes of one hundred million datapoints. Accessing and retrieving mass spatio-temporal trajectory data in any field is hard and inefficient due to limited computational capabilities and incomplete data organization mechanisms. Therefore, we propose an optimized and efficient spatio-temporal trajectory data retrieval method based on the Cloudera Impala query engine, called ESTRI, to enhance the efficiency of mass data sharing. As an excellent query tool for mass data, Impala can be applied for mass spatio-temporal trajectory data sharing. In ESTRI we extend the spatio-temporal trajectory data retrieval function of Impala and design a suitable data partitioning method. In our experiments, the Taiyuan BeiDou (BD bus network is selected, containing 2300 buses with BD positioning sensors, producing 20 million records every day, resulting in two difficulties as described in the Introduction section. In addition, ESTRI and MongoDB are applied in experiments. The experiments show that ESTRI achieves the most efficient data retrieval compared to retrieval using MongoDB for data volumes of fifty million, one hundred million, one hundred and fifty million, and two hundred million. The performance of ESTRI is approximately seven times higher than that of MongoDB. The experiments show that ESTRI is an effective method for retrieving mass spatio-temporal trajectory data. Finally, bus distribution mapping in Taiyuan city is achieved, describing the buses density in different regions at different times throughout the day, which can be applied in future studies of transport, such as traffic scheduling, traffic planning and traffic behavior management in intelligent public transportation systems.

  5. Temporal naturalism

    Science.gov (United States)

    Smolin, Lee

    2015-11-01

    Two people may claim both to be naturalists, but have divergent conceptions of basic elements of the natural world which lead them to mean different things when they talk about laws of nature, or states, or the role of mathematics in physics. These disagreements do not much affect the ordinary practice of science which is about small subsystems of the universe, described or explained against a background, idealized to be fixed. But these issues become crucial when we consider including the whole universe within our system, for then there is no fixed background to reference observables to. I argue here that the key issue responsible for divergent versions of naturalism and divergent approaches to cosmology is the conception of time. One version, which I call temporal naturalism, holds that time, in the sense of the succession of present moments, is real, and that laws of nature evolve in that time. This is contrasted with timeless naturalism, which holds that laws are immutable and the present moment and its passage are illusions. I argue that temporal naturalism is empirically more adequate than the alternatives, because it offers testable explanations for puzzles its rivals cannot address, and is likely a better basis for solving major puzzles that presently face cosmology and physics. This essay also addresses the problem of qualia and experience within naturalism and argues that only temporal naturalism can make a place for qualia as intrinsic qualities of matter.

  6. Seismic quiescence preceding the 2016 central Italy earthquakes

    Science.gov (United States)

    Gentili, S.; Di Giovambattista, R.; Peresan, A.

    2017-11-01

    A complex multiple mainshocks sequence (24/08/2016, Mw 6.0; 26/10/2016, Mw 5.4 and 5.9; 30/10/2016, Mw 6.5) occurred in central Italy, causing the death of nearly 300 people and widespread destruction of entire villages. The Region-Time-Length (RTL) method is used to analyze the seismicity preceding the first Mw 6.0 Amatrice mainshock. This analysis is performed using the earthquake catalogue maintained by the Istituto Nazionale di Geofisica e Vulcanologia (INGV) after a preprocessing, which includes the declustering of aftershocks. A well-evident quiescence that preceded the sequence was detected. The quiescence extended throughout a broad region north of the epicenter. The largest event of the sequence and the aftershocks covered most of the quiescence region, except for a small area to the west. The quiescence started from the beginning of September 2015 and lasted for approximately 1 year up to the Amatrice mainshock.

  7. Arterial stiffening precedes systolic hypertension in diet-induced obesity.

    Science.gov (United States)

    Weisbrod, Robert M; Shiang, Tina; Al Sayah, Leona; Fry, Jessica L; Bajpai, Saumendra; Reinhart-King, Cynthia A; Lob, Heinrich E; Santhanam, Lakshmi; Mitchell, Gary; Cohen, Richard A; Seta, Francesca

    2013-12-01

    Stiffening of conduit arteries is a risk factor for cardiovascular morbidity. Aortic wall stiffening increases pulsatile hemodynamic forces that are detrimental to the microcirculation in highly perfused organs, such as the heart, brain, and kidney. Arterial stiffness is associated with hypertension but presumed to be due to an adaptive response to increased hemodynamic load. In contrast, a recent clinical study found that stiffness precedes and may contribute to the development of hypertension although the mechanisms underlying hypertension are unknown. Here, we report that in a diet-induced model of obesity, arterial stiffness, measured in vivo, develops within 1 month of the initiation of the diet and precedes the development of hypertension by 5 months. Diet-induced obese mice recapitulate the metabolic syndrome and are characterized by inflammation in visceral fat and aorta. Normalization of the metabolic state by weight loss resulted in return of arterial stiffness and blood pressure to normal. Our findings support the hypothesis that arterial stiffness is a cause rather than a consequence of hypertension.

  8. Hydroclimatic conditions preceding the March 2014 Oso landslide

    Science.gov (United States)

    Henn, Brian; Cao, Qian; Lettenmaier, Dennis P.; Magirl, Christopher S.; Mass, Clifford; Bower, J. Brent; St. Laurent, Michael; Mao, Yixin; Perica, Sanja

    2015-01-01

    The 22 March 2014 Oso landslide was one of the deadliest in U.S. history, resulting in 43 fatalities and the destruction of more than 40 structures. We examine synoptic conditions, precipitation records and soil moisture reconstructions in the days, months, and years preceding the landslide. Atmospheric reanalysis shows a period of enhanced moisture transport to the Pacific Northwest beginning on 11 February 2014. The 21- to 42-day periods prior to the landslide had anomalously high precipitation; we estimate that 300-400 mm of precipitation fell at Oso in the 21 days prior to the landslide. Relative only to historical periods ending on 22 March, the return periods of these precipitation accumulations are large (25-88 years). However, relative to the largest accumulations from any time of the year (annual maxima), return periods are more modest (2-6 years). In addition to the 21-42 days prior to the landslide, there is a secondary maximum in the precipitation return periods for the 4 years preceding the landslide. Reconstructed soil moisture was anomalously high prior to the landslide, with a return period that exceeded 40 years about a week before the event.

  9. Human behavior preceding dog bites to the face.

    Science.gov (United States)

    Rezac, P; Rezac, K; Slama, P

    2015-12-01

    Facial injuries caused by dog bites pose a serious problem. The aims of this study were to determine human behavior immediately preceding a dog bite to the face and to assess the effects of victim age and gender and dog sex and size on the location of the bite to the face and the need for medical treatment. Complete data on 132 incidents of bites to the face were analysed. A human bending over a dog, putting the face close to the dog's face, and gazing between victim and dog closely preceded a dog bite to the face in 76%, 19% and 5% of cases, respectively. More than half of the bites were directed towards the central area of the victim's face (nose, lips). More than two thirds of the victims were children, none of the victims was an adult dog owner and only adult dogs bit the face. Victim's age and gender and dog's sex and size did not affect the location of the bite on the face. People who were bitten by large dogs sought medical treatment more often than people who were bitten by small dogs (P dog, putting the face close to the dog's face and gazing between human and dog should be avoided, and children should be carefully and constantly supervised when in the presence of dogs. Copyright © 2015 Elsevier Ltd. All rights reserved.

  10. The Effect of an Education Program Utilising PRECEDE Model on the Quality of Life in Patients with Type 2 Diabetes

    Science.gov (United States)

    Taghdisi, M. H.; Borhani, M.; Solhi, M.; Afkari, M. E.; Hosseini, F.

    2012-01-01

    Background and objective: The problems caused by diabetes have direct and indirect impacts on the quality of life of diabetic patients. An increase of these problems means a decrease in a patient's quality of life. This study was conducted to assess the effect of the educational programme based on the precede model in promoting quality of life of…

  11. Co-Registration of Multi-Temporal dem Based on Sift Algorithm for Change Detection of Glaciers

    Science.gov (United States)

    Huang, Y.; Hu, Q.

    2017-09-01

    To detect the change of geographic objects by using multi-temporal DEM, the data must be co-registered firstly. In this paper, the Scale-Invariant Feature Transform (SIFT) algorithm is used to co-register multi-temporal DEM data and glacier change detection. Firstly, the DEM is converted into image space and extracts feature information, calculate multiple sets of match point coordinates, and achieve swift and accurate DEM data co-registration using SIFT algorithm. Secondly, the difference between co-registered DEM datasets are analysed. Total area change and average rate of change are calculated. Finally, the change of multi-temporal DEM data of glaciers in Langkazi County, Tibet from 2004 to 2014 is detected using the method proposed in this paper. The results indicate that the proposed method is able to detect change of the glaciers and the overall accuracy is higher than 85 %.

  12. Temporal and spatial evaluation of satellite-based rainfall estimates across the complex topographical and climatic gradients of Chile

    Science.gov (United States)

    Zambrano-Bigiarini, Mauricio; Nauditt, Alexandra; Birkel, Christian; Verbist, Koen; Ribbe, Lars

    2017-03-01

    Accurate representation of the real spatio-temporal variability of catchment rainfall inputs is currently severely limited. Moreover, spatially interpolated catchment precipitation is subject to large uncertainties, particularly in developing countries and regions which are difficult to access. Recently, satellite-based rainfall estimates (SREs) provide an unprecedented opportunity for a wide range of hydrological applications, from water resources modelling to monitoring of extreme events such as droughts and floods.This study attempts to exhaustively evaluate - for the first time - the suitability of seven state-of-the-art SRE products (TMPA 3B42v7, CHIRPSv2, CMORPH, PERSIANN-CDR, PERSIAN-CCS-Adj, MSWEPv1.1, and PGFv3) over the complex topography and diverse climatic gradients of Chile. Different temporal scales (daily, monthly, seasonal, annual) are used in a point-to-pixel comparison between precipitation time series measured at 366 stations (from sea level to 4600 m a.s.l. in the Andean Plateau) and the corresponding grid cell of each SRE (rescaled to a 0.25° grid if necessary). The modified Kling-Gupta efficiency was used to identify possible sources of systematic errors in each SRE. In addition, five categorical indices (PC, POD, FAR, ETS, fBIAS) were used to assess the ability of each SRE to correctly identify different precipitation intensities.Results revealed that most SRE products performed better for the humid South (36.4-43.7° S) and Central Chile (32.18-36.4° S), in particular at low- and mid-elevation zones (0-1000 m a.s.l.) compared to the arid northern regions and the Far South. Seasonally, all products performed best during the wet seasons (autumn and winter; MAM-JJA) compared to summer (DJF) and spring (SON). In addition, all SREs were able to correctly identify the occurrence of no-rain events, but they presented a low skill in classifying precipitation intensities during rainy days. Overall, PGFv3 exhibited the best performance everywhere

  13. Computationally efficient video restoration for Nyquist sampled imaging sensors combining an affine-motion-based temporal Kalman filter and adaptive Wiener filter.

    Science.gov (United States)

    Rucci, Michael; Hardie, Russell C; Barnard, Kenneth J

    2014-05-01

    In this paper, we present a computationally efficient video restoration algorithm to address both blur and noise for a Nyquist sampled imaging system. The proposed method utilizes a temporal Kalman filter followed by a correlation-model based spatial adaptive Wiener filter (AWF). The Kalman filter employs an affine background motion model and novel process-noise variance estimate. We also propose and demonstrate a new multidelay temporal Kalman filter designed to more robustly treat local motion. The AWF is a spatial operation that performs deconvolution and adapts to the spatially varying residual noise left in the Kalman filter stage. In image areas where the temporal Kalman filter is able to provide significant noise reduction, the AWF can be aggressive in its deconvolution. In other areas, where less noise reduction is achieved with the Kalman filter, the AWF balances the deconvolution with spatial noise reduction. In this way, the Kalman filter and AWF work together effectively, but without the computational burden of full joint spatiotemporal processing. We also propose a novel hybrid system that combines a temporal Kalman filter and BM3D processing. To illustrate the efficacy of the proposed methods, we test the algorithms on both simulated imagery and video collected with a visible camera.

  14. Querying temporal databases via OWL 2 QL

    CSIR Research Space (South Africa)

    Klarman, S

    2014-06-01

    Full Text Available practical approach to querying the SQL:2011-based temporal data model via the semantic layer of OWL 2 QL. The interval-based temporal query language (TQL), which we propose for this task, is based on naturally characterizable combinations of temporal logic...

  15. MRI-based brain structure volumes in temporal lobe epilepsy patients and their unaffected siblings: a preliminary study.

    LENUS (Irish Health Repository)

    Scanlon, Cathy

    2013-01-01

    Investigating the heritability of brain structure may be useful in simplifying complicated genetic studies in temporal lobe epilepsy (TLE). A preliminary study is presented to determine if volume deficits of candidate brain structures present at a higher rate in unaffected siblings than controls subjects.

  16. A neural circuit transforming temporal periodicity information into a rate-based representation in the mammalian auditory system

    DEFF Research Database (Denmark)

    Dicke, Ulrike; Ewert, Stephan D.; Dau, Torsten

    2007-01-01

    to previous modeling studies, the present circuit does not employ a continuously changing temporal parameter to obtain different best modulation frequencies BMFs of the IC bandpass units. Instead, different BMFs are yielded from varying the number of input units projecting onto different bandpass units...

  17. Sensory neural pathways revisited to unravel the temporal dynamics of the Simon effect : A model-based cognitive neuroscience approach

    NARCIS (Netherlands)

    Salzer, Yael; de Hollander, Gilles; Forstmann, Birte U

    2017-01-01

    The Simon task is one of the most prominent interference tasks and has been extensively studied in experimental psychology and cognitive neuroscience. Despite years of research, the underlying mechanism driving the phenomenon and its temporal dynamics are still disputed. Within the framework of the

  18. Optimization methods of pulse-to-pulse alignment using femtosecond pulse laser based on temporal coherence function for practical distance measurement

    Science.gov (United States)

    Liu, Yang; Yang, Linghui; Guo, Yin; Lin, Jiarui; Cui, Pengfei; Zhu, Jigui

    2018-02-01

    An interferometer technique based on temporal coherence function of femtosecond pulses is demonstrated for practical distance measurement. Here, the pulse-to-pulse alignment is analyzed for large delay distance measurement. Firstly, a temporal coherence function model between two femtosecond pulses is developed in the time domain for the dispersive unbalanced Michelson interferometer. Then, according to this model, the fringes analysis and the envelope extraction process are discussed. Meanwhile, optimization methods of pulse-to-pulse alignment for practical long distance measurement are presented. The order of the curve fitting and the selection of points for envelope extraction are analyzed. Furthermore, an averaging method based on the symmetry of the coherence function is demonstrated. Finally, the performance of the proposed methods is evaluated in the absolute distance measurement of 20 μ m with path length difference of 9 m. The improvement of standard deviation in experimental results shows that these approaches have the potential for practical distance measurement.

  19. Temporal Discounting Is Associated with an Increased Risk of Mortality among Community-Based Older Persons without Dementia.

    Directory of Open Access Journals (Sweden)

    Patricia A Boyle

    Full Text Available Temporal discounting is an important determinant of many health and financial outcomes, but we are not aware of studies that have examined the association of temporal discounting with mortality.Participants were 406 older persons without dementia from the Rush Memory and Aging Project, a longitudinal cohort study of aging. Temporal discounting was measured using standard preference elicitation questions. Individual discount rates were estimated using a well-established hyperbolic function and used to predict the risk of mortality during up to 5 years of follow-up.The mean estimate of discounting was 0.45 (SD = 0.33, range: 0.08-0.90, with higher scores indicating a greater propensity to prefer smaller immediate rewards over larger but delayed ones. During up to 5 years of follow-up (mean = 3.6 years, 62 (15% of 406 persons died. In a proportional hazards model adjusted for age, sex, and education, temporal discounting was associated with an increased risk of mortality (HR = 1.103, 95% CI 1.024, 1.190, p = 0.010. Thus, a person with the highest discount rate (score = 0.90 was about twice more likely to die over the study period compared to a person with the lowest discount rate (score = 0.08. Further, the association of discounting with mortality persisted after adjustment for the level of global cognitive function, the burden of vascular risk factors and diseases, and an indicator of psychological well being (i.e., purpose in life.Temporal discounting is associated with an increased risk of mortality in old age after accounting for global cognitive function and indicators of physical and mental health.

  20. Spatial interactions determine temporal feature integration as revealed by unmasking

    Directory of Open Access Journals (Sweden)

    Michael H. Herzog

    2006-01-01

    Full Text Available Feature integration is one of the most fundamental problems in neuroscience. In a recent contribution, we showed that a trailing grating can diminish the masking effects one vernier exerts on another, preceding vernier. Here, we show that this temporal unmasking depends on neural spatial interactions related to the trailing grating. Hence, our paradigm allows us to study the spatio-temporal interactions underlying feature integration.

  1. Spatio-temporal dynamics of phytoplankton and primary production in Lake Tanganyika using a MODIS based bio-optical time series

    DEFF Research Database (Denmark)

    Bergamino, N; Horion, Stéphanie; Stenuite, S

    2010-01-01

    Lake Tanganyika, the second largest freshwater ecosystem in Africa, is characterised by a significant heterogeneity in phytoplankton concentration linked to its particular hydrodynamics. To gather a proper understanding of primary production, it is necessary to consider spatial and temporal...... dynamics throughout the lake. In the present work, daily MODIS-AQUA satellite measurements were used to estimate chlorophyll-a concentrations and the diffuse attenuation coefficient (K490) for surface waters. The spatial regionalisation of Lake Tanganyika, based on Empirical Orthogonal Functions...

  2. Temporal relationship between depression and dementia – findings from a large community-based 15 year follow-up study

    Science.gov (United States)

    Li, Ge; Wang, Lucy Y.; Shofer, Jane B.; Thompson, Mary Lou; Peskind, Elaine R.; McCormick, Wayne; Bowen, James D.; Crane, Paul K.; Larson, Eric B.

    2012-01-01

    Context Late-life depression is associated with increased risk of dementia but the temporal relationship between depression and development of dementia remains unclear. Objectives To examine the association between risk of dementia and 1) baseline depressive symptoms ; 2) past history of depression, particularly early-life (depression; and 3) individual domains of the Center for Epidemiologic Studies Depression Scale (CESD). Design A large cohort with initially non-demented participants was followed biennially for up to 15 years for incident dementia. Baseline depressive symptoms were assessed using the 11-item version of CESD (CESD-11), and defined as CESD-11 score ≥ 11. Self-reported history of depression was collected at the baseline interview. Cox proportional hazards regression was used to assess the association between depression and the dementia risk. Setting Population-based cohort drawn from members of Group Health Cooperative in Seattle, Washington. Participants A cohort of 3,410 participants without dementia aged ≥ 65 years. Results Over an average of 7.1 years follow-up, 658 participants (19%) developed dementia. At baseline, 9% of participants had depressive symptoms (CESD-11 ≥ 11) and 21% reported a past history of depression. The adjusted hazard ratio (aHR) for dementia associated with baseline depressive symptoms was 1.71 (95% confidence interval 1.37, 2.13), after adjusting for age-at-entry, gender, education, and wave of enrollment. Compared to participants without depression history, those with late-life depression were at increased dementia risk (aHR =1.46 [1.16, 1.84]), but early-life depression had no association with dementia risk (aHR=1.10 [0.83, 1.47]). Depressed mood (aHR 1.48 [1.25, 1.76]) and perceived performance difficulty (aHR 1.39 [1.15, 1.67]) were independently associated with dementia. Conclusions This study confirmed previous observations of an association between late-life depression and increased risk of dementia and

  3. Spatial and temporal patterns of nature-based tourism interactions with whale sharks (Rhincodon typus) at Ningaloo Reef, Western Australia

    Science.gov (United States)

    Anderson, Douglas J.; Kobryn, Halina T.; Norman, Brad M.; Bejder, Lars; Tyne, Julian A.; Loneragan, Neil R.

    2014-07-01

    As with other nature-based tourism ventures, whale shark tourism is expanding rapidly worldwide, which highlights the need to understand more about the nature of these activities. Records of interactions between tour operators and whale sharks at Ningaloo Reef, Western Australia (22.5°S, 113.5°E) were obtained from the Western Australian Department of Parks and Wildlife from 2006 to 2010 and evaluated to determine the scale of the tourism operations and the spatial and temporal distribution of interactions. The number of whale shark tours at Ningaloo increased by approx. 70% (520-886 tours per year) and the number of interactions with whale sharks by 370% between 2006 (694) and 2010 (3254). The locations of whale shark interactions recorded in logbooks (2006-2009) and electronic monitoring systems (2009 and 2010) were used to plot the smoothed densities of tour operator interactions with whale sharks. Generalised linear models were used to investigate how the presence/absence and number of whale shark interactions at North and South Ningaloo were influenced by the distance to the reef crest, the distance to passages and their interaction terms for the aggregated five-year data set. Over the five years, distance to the reef crest was the best predictor of the presence/absence of whale shark interactions at both North (interactions concentrated within 3 km of the reef crest) and South Ningaloo (interactions within 6 km of the reef crest) followed by distance to passages. The reef passages are very significant areas for tourism interactions with whale sharks at Ningaloo. The distribution of interactions at North and South Ningaloo varied from year to year, particularly in the strong La Niña year of 2010, when average sea surface temperatures remained above 24 °C and whale sharks were observed much later in the year than previously (late August). This study demonstrates the value of the data collected by the tour operators at Ningaloo Reef and managed by a

  4. Spatial-Temporal Characteristics and LMDI-Based Impact Factor Decomposition of Agricultural Carbon Emissions in Hotan Prefecture, China

    Directory of Open Access Journals (Sweden)

    Chuanhe Xiong

    2016-03-01

    Full Text Available Greenhouse gas emissions from the agricultural ecosystem account for 7%–20% of the world’s total greenhouse gas emissions, while approximately 17% of China’s carbon emissions are from agriculture. In this study, based on the scientific calculation system of carbon emissions in agriculture, we calculated the carbon emissions of agriculture in the Hotan prefecture between 1999 and 2013 and analyzed their spatial-temporal characteristics; next, we used the LMDI model to study the driving factors of agricultural carbon emissions. The results demonstrated the following: (1 in time series, the agricultural carbon emissions showed three stages of change, i.e., “decline, continued to rise and decline”, during the period of 1999 to 2013 in the Hotan prefecture; (2 In space, the carbon emissions from agricultural land use, paddy fields, enteric fermentation, and manure management were different due to the different sizes of cities and counties. The intensity of agricultural carbon emissions was varied and high, but the agricultural production structure, agricultural carbon emissions structure and other aspects had a high degree of consistency and homogeneity in the cities and counties of the Hotan prefecture; (3 Regarding the driving mechanism, the labor factor, agricultural labor productivity, and planting-animal husbandry carbon intensity are the main factors that increase agricultural carbon emissions in the Hotan prefecture. Compared with 1999, three major factors cumulatively achieved a 199.68% carbon emission increment from 2000 to 2013, of which the labor factor cumulatively increased by 120.04%, the agricultural labor productivity factor cumulatively increased by 54.94% and the planting-animal husbandry carbon intensity factor cumulatively increased by 24.70%. The agricultural production structure factor largely inhibited agricultural carbon emissions of the Hotan prefecture, which cut 99.74% of the carbon emissions from 2000 to 2013

  5. A Visual lexicon to Handle Semantic Similarity in Design precedents

    DEFF Research Database (Denmark)

    Restrepo-Giraldo, John Dairo

    2007-01-01

    is useful, but not enough! This paper concludes proposing a strategy to solve this problem in future systems to handle design precedents. Humans have great ability to recognize if two things are related to each other. For instance, if one takes a vacuum cleaner, an iron and a toaster, it is easy to say......The adequate use of existing knowledge, and not only the creation of completely new solutions, is also an important part of creative thinking. When conceiving a solution, designers oftentimes report having a vague image of the form that will embody the final solution to the design task at hand...... of the image using adjectives, bringing along a series of difficulties: it is impractical for large collections; considers only the viewpoint of the editor; fixes descriptions in time and restricts attribution of meaning. As a solution to this problem, the author has proposed before an approach that uses image...

  6. Experimental Evidence for a Cochlear Source of the Precedence Effect

    DEFF Research Database (Denmark)

    Bianchi, Federica; Verhulst, Sarah; Dau, Torsten

    2013-01-01

    to which peripheral versus central auditory processes contribute to this perceptual phenomenon has remained unclear. The present study investigated the contribution of peripheral processing to the PE through a comparison of physiological and psychoacoustical data in the same human listeners......The precedence effect (PE) refers to the dominance of directional information carried by a direct sound (lead) over the spatial information contained in its multiple reflections (lags) in sound localization. Although the processes underlying the PE have been largely investigated, the extent......–lag interactions at the level of the basilar membrane (BM) in the cochlea. The CEOAE-derived peripheral and monaural lag suppression was largest for ICIs of 1–4 ms. Auditory-evoked brainstem responses (ABRs) were used to investigate monaural and binaural lag suppression at the brainstem level. The responses...

  7. Activities preceding a decline in the paratuberculosis test prevalence

    DEFF Research Database (Denmark)

    Nielsen, Søren Saxmose; Toft, Nils

    . A challenge in evaluation of activities in a national programme it is essentially a sample size of one without a control group. Therefore, the apparent effect of activities on programme level can only be descriptive. Our objective was to describe the decline in the test-prevalence along with the activities...... for a “continuous” flow of diagnostic test information four times annually in each herd. This information can be used for detection and management of infectious animals and for prevalence monitoring....... preceding this decline. The cohort of herds enrolled in 2006-2007 had an average estimated within-herd test-prevalence of 10% at start. By January 2014 this had declined to 2%. The test-prevalence in the cohort of herds enrolled in 2008-2010 started at approximately 6% and by January 2014 was reduced...

  8. Spatiotemporal neurodynamics of automatic temporal expectancy in 9-month old infants.

    Science.gov (United States)

    Mento, Giovanni; Valenza, Eloisa

    2016-11-04

    Anticipating events occurrence (Temporal Expectancy) is a crucial capacity for survival. Yet, there is little evidence about the presence of cortical anticipatory activity from infancy. In this study we recorded the High-density electrophysiological activity in 9 month-old infants and adults undergoing an audio-visual S1-S2 paradigm simulating a lifelike "Peekaboo" game inducing automatic temporal expectancy of smiling faces. The results indicate in the S2-preceding Contingent Negative Variation (CNV) an early electrophysiological signature of expectancy-based anticipatory cortical activity. Moreover, the progressive CNV amplitude increasing across the task suggested that implicit temporal rule learning is at the basis of expectancy building-up over time. Cortical source reconstruction suggested a common CNV generator between adults and infants in the right prefrontal cortex. The decrease in the activity of this area across the task (time-on-task effect) further implied an early, core role of this region in implicit temporal rule learning. By contrast, a time-on-task activity boost was found in the supplementary motor area (SMA) in adults and in the temporoparietal regions in infants. Altogether, our findings suggest that the capacity of the human brain to translate temporal predictions into anticipatory neural activity emerges ontogenetically early, although the underlying spatiotemporal cortical dynamics change across development.

  9. Human conchal cartilage and temporal fascia: an evidence-based roadmap from rhinoplasty to an in vivo study and beyond.

    Science.gov (United States)

    Cimpean, Anca Maria; Crăiniceanu, Zorin; Mihailovici, Dorina; Bratu, Tiberiu; Raica, Marius

    2014-01-01

    Conchal cartilage or cartilage/ temporal fascia composite grafting (DC-F) used for rhinoplasty is applied by plastic surgeons for reconstructive purposes. Previous studies on experimental models such as mice or rabbits have elucidated on the late events following grafting, with tissue specimens being harvested two months after implantation. Early microscopic and molecular events following DC-F grafting are completely unknown. We designed a chick embryo chorioallantoic membrane model for human grafts study, regarding the dynamic observation of graft survival and its mutual interrelation with the chick embryo chorioallantoic membrane microenvironment. The DC-F graft preserved its cartilage component in a normal state compared to cartilage graft-only because of protective factors provided by temporal fascia. Its strong adherence to the cartilage, lack of angiogenic factors and high content of collagen IV-derived fragments with anti-angiogenic effects make the temporal fascia a good protective tissue to prevent implanted cartilage degeneration. The cartilage graft produced high inflammation, stromal fibrosis and activated angiogenic cascade through VEGF-mediated pathways followed by cartilage degeneration. Also, high content of podoplanin from conchal cartilage chondrocytes exerted a major role in inflammation accompanying cartilage graft. The presently employed experimental model allowed us to characterize the early histological and molecular events triggered by temporal fascia, cartilage or composite graft DC-F implanted on chick embryo chorioallantoic membrane. Our microscopic and molecular observations may help explain some post-surgical complications generated after using cartilage alone as biomaterial for nasal augmentation, supporting the use of DC-F composite graft, with the aim to reduce unwanted post-surgical events. Copyright © 2014 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

  10. Development of a Rheumatoid Arthritis Education Program using the PRECEDE_PROCEED Model

    Directory of Open Access Journals (Sweden)

    Kaveh Bahmanpour

    2011-12-01

    Full Text Available Background: In order to help rheumatoid arthritis (RA patients in carrying out and attaining relevant self-care behaviors and adaptation to the physical limitations of this disease and, conse-quently, promoting their level of health status, an education program based on the PRECEDE component of the PRECEDE–PROCEED model targeting patients with RA was developed. This paper describes the planning of a RA Patient Education Program (RAPEP designed to promote their quality of life.Methods: The development of the program began with a comprehensive review of the literature. This included a review of the signs and symptoms of RA, accompanying functional disabilities, previous educational programs and the effect of the disease on the patient’s quality of life. Be-sides, in order to help inform RAPEP program development, and organize the survey according to the factors identified in the PRECEDE model a cross-sectional survey was applied on a non-prob-ability sample of 181 outpatients in Yazd, center of Iran.Results: The quality of life (QOL problem identified was the considerable low role functioning, health perception and physical functioning due to chronic pain. One of the most significant modi-fiable behavioral factors impacting pain and functional limitations was self-care behaviors in RA patients. Higher level of knowledge, attitude, self-efficacy, enabling factors and social support is associated with better self-care behavior.Conclusions: The PRECEDE component of the PRECEDE–PROCEED model provided a com-prehensive conceptual framework for the development of RAPEP aiming at RA patients in Yazd. Further research to evaluate this educational program is suggested.

  11. Factors preceding CRM readiness in small- and medium-sized tourism enterprises

    Directory of Open Access Journals (Sweden)

    Dinesh Vallabh

    2015-02-01

    Full Text Available Orientation: Customer relationship management (CRM is important to organisations striving for competitive advantage through building relationships with their customers.Research purpose: This study identified the factors preceding CRM and assessed selected South African small- and medium-sized tourism enterprises’ (SMTEs readiness for CRM.Motivation: CRM is likely to enhance SMTEs’ competitiveness. However, successful adoption and implementation of CRM is unlikely unless the organisation is ready for it.Research design, approach and method: A quantitative research approach and survey questionnaire yielded primary data from 332 respondent organisations selected by systematic sampling. Exploratory factor analysis was used to identify the latent factors preceding CRM readiness. Organisational CRM readiness was assessed based on CRM maturity in terms of data collection, use and sharing throughout the organisation.Main findings: Respondent-organisations performed well on the four factors preceding CRM readiness − business strategy, customer strategy, touch points and competencies, skills and technology and also on data collections and use, but not on data sharing.Practical/Managerial implications: CRM practice is believed to assist organisations in tailoring products and services to customers’ needs, providing customer satisfaction, enhancing customer retention and ultimately improving the organisation’s competitiveness and profitability. CRM might fail if SMTEs do not have CRM-enabling conditions in place and a CRM readiness audit should therefore be performed.Contribution: The study contributes to a largely under-researched area concerning CRM in SMTEs by providing an improved understanding of the factors that will enable SMTEs to engage in CRM activities.

  12. Sleeping Pattern of Medical Students Preceding Viva Examination and Their Performance

    Directory of Open Access Journals (Sweden)

    Mukhtar Ansari

    2016-10-01

    Full Text Available Introduction: Sleep is an important determinant of keeping healthy physically and mentally. Deviation in sleep is a common problem among students during examinations. The purpose of this study is to determine students’ sleep pattern during night preceding viva examination and its correlation with performance.  Methods: This was a cross-sectional prospective study conducted between January and February 2014 among 1st and 2nd year MBBS students of National Medical College, Birgunj, Nepal who appeared in University’s  nal practical examinations. Based on simple random sampling approach, each of the 280 participants was allowed to pick out ve pieces of lottery papers and they were asked the ve questions resembling the number in the list of questions.  Results: Among the total 280 students, 74.6% were from India and 25.4% were from Nepal, and majorities (63% of them were males. Fifty two percent of the students either could not sleep at all or slept just for 1 to 1.5 hours while 12% slept for 5 to 6.5 hours. Two-third (66% of the students was able enough to achieve one to two scores, and only 1.8% could succeed to get the maximum score of ve. The correlation between hours of sleep preceding examination and the score achieved was positively (r=0.701 and statistically signi cantly correlated (p<0.001. Conclusions: There is a trend among the medical students either not to sleep or sleep only for few hours preceding viva examination that result in poor performance in examinations.  Keywords: medical; Nepal; performance; sleep deprivation; students.

  13. Quantitative measurement of zinc secretion from pancreatic islets with high temporal resolution using droplet-based microfluidics.

    Science.gov (United States)

    Easley, Christopher J; Rocheleau, Jonathan V; Head, W Steven; Piston, David W

    2009-11-01

    We assayed glucose-stimulated insulin secretion (GSIS) from live, murine islets of Langerhans in microfluidic devices by the downstream formation of aqueous droplets. Zinc ions, which are cosecreted with insulin from beta-cells, were quantitatively measured from single islets with high temporal resolution using a fluorescent indicator, FluoZin-3. Real-time storage of secretions into droplets (volume of 0.470 +/- 0.009 nL) effectively preserves the temporal chemical information, allowing reconstruction of the secretory time record. The use of passive flow control within the device removes the need for syringe pumps, requiring only a single hand-held syringe. Under stimulatory glucose levels (11 mM), bursts of zinc as high as approximately 800 fg islet(-1) min(-1) were measured. Treatment with diazoxide effectively blocked zinc secretion, as expected. High temporal resolution reveals two major classes of oscillations in secreted zinc, with predominate periods at approximately 20-40 s and approximately 5-10 min. The more rapid oscillation periods match closely with those of intraislet calcium oscillations, while the slower oscillations are consistent with insulin pulses typically measured in bulk islet experiments or in the bloodstream. This droplet sampling technique should be widely applicable to time-resolved cellular secretion measurements, either in real-time or for postprocessing.

  14. Effect of preceding stimulation on sound localization and its representation in the auditory midbrain.

    Science.gov (United States)

    Tolnai, Sandra; Beutelmann, Rainer; Klump, Georg M

    2017-02-01

    Prior stimulation can influence the perception of sound source location. Some psychophysical sound localization procedures differ in the amount of prior stimulation, which may affect measures of localization accuracy. If and how particularly the number of preceding stimuli affects sound localization and the neural representation of sound source position has not been investigated so far and will be the focus of the present report. We trained Mongolian gerbils in a left/right discrimination task where the target stimulus was preceded by silence or followed a number of reference stimuli. Localization thresholds decreased with the number of references presented before the target stimulus. The smallest thresholds were found after the presentation of a train of 5 reference stimuli and after silence. We recorded from units in the inferior colliculus (IC) of anaesthetized gerbils using virtual-acoustic space stimuli mimicking the ones used in the behavioural task and applied signal detection theory to compare behavioural and neurometric thresholds. We found that neurometric thresholds based on spike rate information of single units covered a wide range of threshold values but only neurometric thresholds that were based on responses of small populations of IC units reached consistently thresholds we also observed in the behavioural experiment. Unlike behavioural thresholds, however, neurometric thresholds were independent of the number of reference stimuli suggesting that processing stages downstream from the IC might better reflect the effect of prior stimulation. © 2016 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

  15. Association between fatigue and pain in rheumatoid arthritis: does pain precede fatigue or does fatigue precede pain?

    NARCIS (Netherlands)

    Dartel, S.A.A. van; Repping-Wuts, J.W.J.; Hoogmoed, D. van; Bleijenberg, G.; Riel, P.L.C.M. van; Fransen, J.

    2013-01-01

    OBJECTIVE: Fatigue and pain are important symptoms for patients with rheumatoid arthritis (RA), but their temporal association is unknown. Therefore, the objective of this study was to investigate the longitudinal relationship between fatigue and pain in patients with RA using time-lag models.

  16. Methods and tools for temporal knowledge harvesting

    OpenAIRE

    Wang, Yafang

    2013-01-01

    To extend the traditional knowledge base with temporal dimension, this thesis offers methods and tools for harvesting temporal facts from both semi-structured and textual sources. Our contributions are briefly summarized as follows. 1. Timely YAGO: A temporal knowledge base called Timely YAGO (T-YAGO) which extends YAGO with temporal attributes is built. We define a simple RDF-style data model to support temporal knowledge. 2. PRAVDA: To be able to harvest as many temporal facts from free...

  17. Perirhinal and hippocampal contributions to visual recognition memory can be distinguished from those of occipito-temporal structures based on conscious awareness of prior occurrence.

    Science.gov (United States)

    Danckert, S L; Gati, J S; Menon, R S; Köhler, S

    2007-01-01

    The ability of humans to distinguish consciously between new and previously encountered objects can be probed with visual recognition memory tasks that require explicit old-new discriminations. Medial temporal-lobe (MTL) lesions impair performance on such tasks. Within the MTL, both perirhinal cortex and the hippocampus have been implicated. Cognitive processes can also be affected by past object encounters in the absence of conscious recognition, as in repetition priming tasks. Past functional neuroimaging findings in healthy individuals suggest that even in tasks that require conscious recognition decisions for visual stimuli, posterior cortical structures in the ventral visual pathway distinguish between old and new objects at a nonconscious level. Conclusive evidence that differentiates the neural underpinnings of conscious from nonconscious processes in recognition memory, however, is still missing. In particular, functional magnetic resonance imaging (fMRI) findings for the MTL have been inconsistent towards this end. In the present fMRI study, we tested whether perirhinal and hippocampal contributions to recognition memory can be distinguished from those of occipito-temporal structures in the ventral visual pathway based on the participants' reported conscious awareness of prior occurrence. Images of objects with a large degree of feature overlap served as stimuli; they were selected to ensure an involvement of perirhinal cortex in the present recognition task, based on evidence from past lesion-based research. We found that both perirhinal cortex and occipito-temporal cortex showed a differential old-new response that reflected a repetition-related decrease in activity (i.e., new > old). Whereas in perirhinal cortex this decrease was observed with respect to whether subjects reported objects to be old or new, irrespective of the true item status, in occipito-temporal cortex it occurred in relation to whether objects were truly old or new, irrespective of

  18. Generating spatial precipitation ensembles: impact of temporal correlation structure

    Directory of Open Access Journals (Sweden)

    O. Rakovec

    2012-09-01

    Full Text Available Sound spatially distributed rainfall fields including a proper spatial and temporal error structure are of key interest for hydrologists to force hydrological models and to identify uncertainties in the simulated and forecasted catchment response. The current paper presents a temporally coherent error identification method based on time-dependent multivariate spatial conditional simulations, which are conditioned on preceding simulations. A sensitivity analysis and real-world experiment are carried out within the hilly region of the Belgian Ardennes. Precipitation fields are simulated for pixels of 10 km × 10 km resolution. Uncertainty analyses in the simulated fields focus on (1 the number of previous simulation hours on which the new simulation is conditioned, (2 the advection speed of the rainfall event, (3 the size of the catchment considered, and (4 the rain gauge density within the catchment. The results for a sensitivity analysis show for typical advection speeds >20 km h−1, no uncertainty is added in terms of across ensemble spread when conditioned on more than one or two previous hourly simulations. However, for the real-world experiment, additional uncertainty can still be added when conditioning on a larger number of previous simulations. This is because for actual precipitation fields, the dynamics exhibit a larger spatial and temporal variability. Moreover, by thinning the observation network with 50%, the added uncertainty increases only slightly and the cross-validation shows that the simulations at the unobserved locations are unbiased. Finally, the first-order autocorrelation coefficients show clear temporal coherence in the time series of the areal precipitation using the time-dependent multivariate conditional simulations, which was not the case using the time-independent univariate conditional simulations. The presented work can be easily implemented within a hydrological calibration and data assimilation

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

    Science.gov (United States)

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

    2017-01-01

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

  20. Promoter Methylation Precedes Chromosomal Alterations in Colorectal Cancer Development

    Directory of Open Access Journals (Sweden)

    Sarah Derks

    2006-01-01

    Full Text Available Background: Colorectal cancers are characterized by genetic and epigenetic alterations. This study aimed to explore the timing of promoter methylation and relationship with mutations and chromosomal alterations in colorectal carcinogenesis. Methods: In a series of 47 nonprogressed adenomas, 41 progressed adenomas (malignant polyps, 38 colorectal carcinomas and 18 paired normal tissues, we evaluated promoter methylation status of hMLH1, O6MGMT, APC, p14ARF, p16INK4A, RASSF1A, GATA-4, GATA-5, and CHFR using methylation-specific PCR. Mutation status of TP53, APC and KRAS were studied by p53 immunohistochemistry and sequencing of the APC and KRAS mutation cluster regions. Chromosomal alterations were evaluated by comparative genomic hybridization. Results: Our data demonstrate that nonprogressed adenomas, progressed adenomas and carcinomas show similar frequencies of promoter methylation for the majority of the genes. Normal tissues showed significantly lower frequencies of promoter methylation of APC, p16INK4A, GATA-4, and GATA-5 (P-values: 0.02, 0.02, 1.1×10−5 and 0.008 respectively. P53 immunopositivity and chromosomal abnormalities occur predominantly in carcinomas (P values: 1.1×10−5 and 4.1×10−10. Conclusions: Since promoter methylation was already present in nonprogressed adenomas without chromosomal alterations, we conclude that promoter methylation can be regarded as an early event preceding TP53 mutation and chromosomal abnormalities in colorectal cancer development.

  1. Interpretation in Social Anxiety: When Meaning Precedes Ambiguity.

    Science.gov (United States)

    Beard, Courtney; Amir, Nader

    2009-01-01

    Cognitive models of anxiety posit that negative beliefs influence socially anxious individuals' interpretation of ambiguous social cues. However, paradigms used to assess interpretation bias in social anxiety have not addressed such beliefs. Furthermore, studies have assessed interpretation with either self-report or reaction time paradigms, rather than using both methods. In the current study, socially anxious and non-anxious participants completed the Word Sentence Association Paradigm (WSAP). In the WSAP, participants decide whether or not a word (implying a threat or benign interpretation) is related to an ambiguous sentence. Threat or benign meanings preceded the ambiguity in order to examine the influence of positive and negative beliefs on interpretation of ambiguous information. The WSAP results in two types of interpretation indices: (1) response latency to make relatedness decisions for threat and benign interpretations, and (2) endorsement rates of the relatedness of threat and benign interpretations to ambiguous sentences. Results revealed a threat interpretation bias and a lack of a benign interpretation bias in both reaction time and self-report data. Threat and benign biases were not strongly correlated. These findings support the distinction between threat and benign interpretation biases.

  2. Neurological Evidence Linguistic Processes Precede Perceptual Simulation in Conceptual Processing

    Directory of Open Access Journals (Sweden)

    Max eLouwerse

    2012-10-01

    Full Text Available There is increasing evidence from response time experiments that language statistics and perceptual simulations both play a role in conceptual processing. In an EEG experiment we compared neural activity in cortical regions commonly associated with linguistic processing and visual perceptual processing to determine to what extent symbolic and embodied accounts of cognition applied. Participants were asked to determine the semantic relationship of word pairs (e.g., sky – ground or to determine their iconic relationship (i.e., if the presentation of the pair matched their expected physical relationship. A linguistic bias was found towards the semantic judgment task and a perceptual bias was found towards the iconicity judgment task. More importantly, conceptual processing involved activation in brain regions associated with both linguistic and perceptual processes. When comparing the relative activation of linguistic cortical regions with perceptual cortical regions, the effect sizes for linguistic cortical regions were larger than those for the perceptual cortical regions early in a trial with the reverse being true later in a trial. These results map upon findings from other experimental literature and provide further evidence that processing of concept words relies both on language statistics and on perceptual simulations, whereby linguistic processes precede perceptual simulation processes.

  3. Nonseizure SUDEP: Sudden unexpected death in epilepsy without preceding epileptic seizures.

    Science.gov (United States)

    Lhatoo, Samden D; Nei, Maromi; Raghavan, Manoj; Sperling, Michael; Zonjy, Bilal; Lacuey, Nuria; Devinsky, Orrin

    2016-07-01

    To describe the phenomenology of monitored sudden unexpected death in epilepsy (SUDEP) occurring in the interictal period where death occurs without a seizure preceding it. We report a case series of monitored definite and probable SUDEP where no electroclinical evidence of underlying seizures was found preceding death. Three patients (two definite and one probable) had SUDEP. They had a typical high SUDEP risk profile with longstanding intractable epilepsy and frequent generalized tonic-clonic seizures (GTCS). All patients had varying patterns of respiratory and bradyarrhythmic cardiac dysfunction with profound electroencephalography (EEG) suppression. In two patients, patterns of cardiorespiratory failure were similar to those seen in some patients in the Mortality in Epilepsy Monitoring Units Study (MORTEMUS). SUDEP almost always occur postictally, after GTCS and less commonly after a partial seizure. Monitored SUDEP or near-SUDEP cases without a seizure have not yet been reported in literature. When nonmonitored SUDEP occurs in an ambulatory setting without an overt seizure, the absence of EEG information prevents the exclusion of a subtle seizure. These cases confirm the existence of nonseizure SUDEP; such deaths may not be prevented by seizure detection-based devices. SUDEP risk in patients with epilepsy may constitute a spectrum of susceptibility wherein some are relatively immune, death occurs in others with frequent GTCS with one episode of seizure ultimately proving fatal, while in others still, death may occur even in the absence of a seizure. We emphasize the heterogeneity of SUDEP phenomena. Wiley Periodicals, Inc. © 2016 International League Against Epilepsy.

  4. An Improved STARFM with Help of an Unmixing-Based Method to Generate High Spatial and Temporal Resolution Remote Sensing Data in Complex Heterogeneous Regions

    Directory of Open Access Journals (Sweden)

    Dengfeng Xie

    2016-02-01

    Full Text Available Remote sensing technology plays an important role in monitoring rapid changes of the Earth's surface. However, sensors that can simultaneously provide satellite images with both high temporal and spatial resolution haven’t been designed yet. This paper proposes an improved spatial and temporal adaptive reflectance fusion model (STARFM with the help of an Unmixing-based method (USTARFM to generate the high spatial and temporal data needed for the study of heterogeneous areas. The results showed that the USTARFM had higher accuracy than STARFM methods in two aspects of analysis: individual bands and of heterogeneity analysis. Taking the predicted NIR band as an example, the correlation coefficients (r for the USTARFM, STARFM and unmixing methods were 0.96, 0.95, 0.90, respectively (p-value < 0.001; Root Mean Square Error (RMSE values were 0.0245, 0.0300, 0.0401, respectively; and ERGAS values were 0.5416, 0.6507, 0.8737, respectively. The USTARM showed consistently higher performance than STARM when the degree of heterogeneity ranged from 2 to 10, highlighting that the use of this method provides the capacity to solve the data fusion problems faced when using STARFM. Additionally, the USTARFM method could help researchers achieve better performance than STARFM at a smaller window size from its heterogeneous land surface quantitative representation.

  5. Temporal dynamics of the gut microbiota in people sharing a confined environment, a 520-day ground-based space simulation, MARS500.

    Science.gov (United States)

    Turroni, Silvia; Rampelli, Simone; Biagi, Elena; Consolandi, Clarissa; Severgnini, Marco; Peano, Clelia; Quercia, Sara; Soverini, Matteo; Carbonero, Franck G; Bianconi, Giovanna; Rettberg, Petra; Canganella, Francesco; Brigidi, Patrizia; Candela, Marco

    2017-03-24

    The intestinal microbial communities and their temporal dynamics are gaining increasing interest due to the significant implications for human health. Recent studies have shown the dynamic behavior of the gut microbiota in free-living, healthy persons. To date, it is not known whether these dynamics are applicable during prolonged life sharing in a confined and controlled environment. The MARS500 project, the longest ground-based space simulation ever, provided us with a unique opportunity to trace the crew microbiota over 520 days of isolated confinement, such as that faced by astronauts in real long-term interplanetary space flights, and after returning to regular life, for a total of 2 years. According to our data, even under the strictly controlled conditions of an enclosed environment, the human gut microbiota is inherently dynamic, capable of shifting between different steady states, typically with rearrangements of autochthonous members. Notwithstanding a strong individuality in the overall gut microbiota trajectory, some key microbial components showed conserved temporal dynamics, with potential implications for the maintenance of a health-promoting, mutualistic microbiota configuration. Sharing life in a confined habitat does not affect the resilience of the individual gut microbial ecosystem, even in the long term. However, the temporal dynamics of certain microbiota components should be monitored when programming future mission simulations and real space flights, to prevent breakdowns in the metabolic and immunological homeostasis of the crewmembers.

  6. Insights into Intrinsic Brain Networks based on Graph Theory and PET in right- compared to left-sided Temporal Lobe Epilepsy.

    Science.gov (United States)

    Vanicek, Thomas; Hahn, Andreas; Traub-Weidinger, Tatjana; Hilger, Eva; Spies, Marie; Wadsak, Wolfgang; Lanzenberger, Rupert; Pataraia, Ekaterina; Asenbaum-Nan, Susanne

    2016-06-28

    The human brain exhibits marked hemispheric differences, though it is not fully understood to what extent lateralization of the epileptic focus is relevant. Preoperative [(18)F]FDG-PET depicts lateralization of seizure focus in patients with temporal lobe epilepsy and reveals dysfunctional metabolic brain connectivity. The aim of the present study was to compare metabolic connectivity, inferred from inter-regional [(18)F]FDG PET uptake correlations, in right-sided (RTLE; n = 30) and left-sided TLE (LTLE; n = 32) with healthy controls (HC; n = 31) using graph theory based network analysis. Comparing LTLE and RTLE and patient groups separately to HC, we observed higher lobar connectivity weights in RTLE compared to LTLE for connections of the temporal and the parietal lobe of the contralateral hemisphere (CH). Moreover, especially in RTLE compared to LTLE higher local efficiency were found in the temporal cortices and other brain regions of the CH. The results of this investigation implicate altered metabolic networks in patients with TLE specific to the lateralization of seizure focus, and describe compensatory mechanisms especially in the CH of patients with RTLE. We propose that graph theoretical analysis of metabolic connectivity using [(18)F]FDG-PET offers an important additional modality to explore brain networks.

  7. Multiple-Parameter Estimation Method Based on Spatio-Temporal 2-D Processing for Bistatic MIMO Radar.

    Science.gov (United States)

    Yang, Shouguo; Li, Yong; Zhang, Kunhui; Tang, Weiping

    2015-12-14

    A novel spatio-temporal 2-dimensional (2-D) processing method that can jointly estimate the transmitting-receiving azimuth and Doppler frequency for bistatic multiple-input multiple-output (MIMO) radar in the presence of spatial colored noise and an unknown number of targets is proposed. In the temporal domain, the cross-correlation of the matched filters' outputs for different time-delay sampling is used to eliminate the spatial colored noise. In the spatial domain, the proposed method uses a diagonal loading method and subspace theory to estimate the direction of departure (DOD) and direction of arrival (DOA), and the Doppler frequency can then be accurately estimated through the estimation of the DOD and DOA. By skipping target number estimation and the eigenvalue decomposition (EVD) of the data covariance matrix estimation and only requiring a one-dimensional search, the proposed method achieves low computational complexity. Furthermore, the proposed method is suitable for bistatic MIMO radar with an arbitrary transmitted and received geometrical configuration. The correction and efficiency of the proposed method are verified by computer simulation results.

  8. A novel on-line spatial-temporal k-anonymity method for location privacy protection from sequence rules-based inference attacks.

    Science.gov (United States)

    Zhang, Haitao; Wu, Chenxue; Chen, Zewei; Liu, Zhao; Zhu, Yunhong

    2017-01-01

    Analyzing large-scale spatial-temporal k-anonymity datasets recorded in location-based service (LBS) application servers can benefit some LBS applications. However, such analyses can allow adversaries to make inference attacks that cannot be handled by spatial-temporal k-anonymity methods or other methods for protecting sensitive knowledge. In response to this challenge, first we defined a destination location prediction attack model based on privacy-sensitive sequence rules mined from large scale anonymity datasets. Then we proposed a novel on-line spatial-temporal k-anonymity method that can resist such inference attacks. Our anti-attack technique generates new anonymity datasets with awareness of privacy-sensitive sequence rules. The new datasets extend the original sequence database of anonymity datasets to hide the privacy-sensitive rules progressively. The process includes two phases: off-line analysis and on-line application. In the off-line phase, sequence rules are mined from an original sequence database of anonymity datasets, and privacy-sensitive sequence rules are developed by correlating privacy-sensitive spatial regions with spatial grid cells among the sequence rules. In the on-line phase, new anonymity datasets are generated upon LBS requests by adopting specific generalization and avoidance principles to hide the privacy-sensitive sequence rules progressively from the extended sequence anonymity datasets database. We conducted extensive experiments to test the performance of the proposed method, and to explore the influence of the parameter K value. The results demonstrated that our proposed approach is faster and more effective for hiding privacy-sensitive sequence rules in terms of hiding sensitive rules ratios to eliminate inference attacks. Our method also had fewer side effects in terms of generating new sensitive rules ratios than the traditional spatial-temporal k-anonymity method, and had basically the same side effects in terms of non

  9. Investigation of models with temporal and spatial interference in image based dosimetry of {sup 177}Lu-labelled radioligand therapies

    Energy Technology Data Exchange (ETDEWEB)

    Delker, Andreas

    2016-07-12

    In targeted radio ligand therapy determination of the regional distribution of the radiation dose is mandatory for the development of therapy strategies which aim for maximizing the therapeutic effect on the tumor, while reducing radiation exposure to healthy tissue. For this purpose, after administration of the therapeutic agent, sequential measurements with a scintillation camera are required to quantitatively assess the kinetics and distribution of the radiopharmaceutical in the body. To improve the accuracy and robustness of existing dosimetric concepts, the kinetic of Lu-177-DOTATATE, a radiopharmaceutical for the treatment of patients with neuroendocrine tumors, was examined in depth. Subsequently, the findings from this study were used to carry out the first image-based dosimetry for the new active substance Lu-177-PSMA, a radiopharmaceutical for the treatment of patients with metastatic prostate cancer. Due to the specific distribution pattern of this ligand, overlay effects in the 2-dimensional (2-D) planar projection were observed. Therefore a quantitative 3-dimensional (3-D) SPECT imaging technique was established and optimized for dosimetry. To characterize the dynamics of Lu-177-DOTATATE, whole-body planar projections of 105 patients were recorded at 1, 24, 48 and 72 h after injection. Furthermore, the first hour beginning with the start of the therapeutic agent administration was measured in 12 time frames with duration of 5 min each. An optimal dose model was introduced for the kidneys, for those being a risk organ in this therapy, which consisted of three phases: a linear increase of tracer accumulation during infusion, followed by a 2-phase model being described by a bi-exponential decline. This full data model served as a basis for comparison with reduced data models based on mono-exponentials which made use of all four (at 1, 24, 48 and 72 h after injection) or the last three whole-body scintigraphies. The established quantitative 3-D SPECT

  10. Temporal bone imaging

    Energy Technology Data Exchange (ETDEWEB)

    Lemmerling, Marc [Algemeen Ziekenhuis Sint-Lucas, Gent (Belgium). Dept. of Radiology; Foer, Bert de (ed.) [Sint-Augustinus Ziekenhuis, Wilrijk (Belgium). Dept. of Radiology

    2015-04-01

    Complete overview of imaging of normal and diseased temporal bone. Straightforward structure to facilitate learning. Detailed consideration of newer imaging techniques, including the hot topic of diffusion-weighted imaging. Includes a chapter on anatomy that will be of great help to the novice interpreter of imaging findings. Excellent illustrations throughout. This book provides a complete overview of imaging of normal and diseased temporal bone. After description of indications for imaging and the cross-sectional imaging anatomy of the area, subsequent chapters address the various diseases and conditions that affect the temporal bone and are likely to be encountered regularly in clinical practice. The classic imaging methods are described and discussed in detail, and individual chapters are included on newer techniques such as functional imaging and diffusion-weighted imaging. There is also a strong focus on postoperative imaging. Throughout, imaging findings are documented with the aid of numerous informative, high-quality illustrations. Temporal Bone Imaging, with its straightforward structure based essentially on topography, will prove of immense value in daily practice.

  11. Modelling spatial and temporal dynamics of gross primary production in the Sahel from earth-observation-based photosynthetic capacity and quantum efficiency

    DEFF Research Database (Denmark)

    Tagesson, Håkan Torbern; Ardoe, Jonas; Cappelaere, Bernard

    2017-01-01

    . MOD17A2H GPP (collection 6) drastically underestimated GPP, most likely because maximum light use efficiency is set too low for semi-arid ecosystems in the MODIS algorithm. Intra-annual dynamics in Fopt were closely related to SIWSI being sensitive to equivalent water thickness, whereas α was closely......: (1) to evaluate the MOD17A2H GPP (collection 6) product against GPP based on eddy covariance (EC) for six sites across the Sahel; (2) to characterize relationships between spatial and temporal variability in EC-based photosynthetic capacity (Fopt) and quantum efficiency (α) and vegetation indices...... related to RDVI being affected by chlorophyll abundance. Spatial and inter-annual dynamics in Fopt and α were closely coupled to NDVI and RDVI, respectively. Modelled GPP based on Fopt and α upscaled using EO-based indices reproduced in situ GPP well for all except a cropped site that was strongly...

  12. Perceived control increases the reward positivity and stimulus preceding negativity.

    Science.gov (United States)

    Mühlberger, Christina; Angus, Douglas Jozef; Jonas, Eva; Harmon-Jones, Cindy; Harmon-Jones, Eddie

    2017-02-01

    The reward positivity (RewP) and the stimulus preceding negativity (SPN), two ERPs associated with reward delivery and reward anticipation, are modulated by motivational intensity. Motivational intensity is the effort organisms would make to exert behaviors, and it varies with the difficulty of exerting that behavior. If a task is perceived as impossible, which means that one does not have control over own outcomes, motivational intensity is low. In the current study, we tested the prediction that perceiving control over one's outcomes increases both the RewP to feedback and the SPN prior to feedback compared to perceiving no control. We also examined whether P300 and LPP amplitudes to reward and nonreward images were similarly modulated. Twenty-five female participants completed a gambling task in which correct choices were followed by pictures of attractive men and incorrect choices were followed by pictures of rocks. To manipulate perceived control, participants were told that, in one block of trials, they could learn a mouse-click rule in order to see only pictures of men (high perceived control condition), while in the other block, the pictures would appear randomly (low perceived control condition). However, in both conditions, feedback appeared randomly. Although the RewP was elicited in both blocks, the RewP and SPN were higher in the high perceived control condition (i.e., when participants thought that they could influence their outcomes). Perceived control did not modulate the P300 and LPP to pictures. The results suggest that approach motivation and its intensity modulate the processing of performance feedback. © 2016 Society for Psychophysiological Research.

  13. Integrated Vehicle Ground Vibration Testing of Manned Spacecraft: Historical Precedent

    Science.gov (United States)

    Lemke, Paul R.; Tuma, Margaret L.; Askins, Bruce R.

    2008-01-01

    For the first time in nearly 30 years, NASA is developing a new manned space flight launch system. The Ares I will carry crew and cargo to not only the International Space Station, but onward for the future exploration of the Moon and Mars. The Ares I control system and structural designs use complex computer models for their development. An Integrated Vehicle Ground Vibration Test (IVGVT) will validate the efficacy of these computer models. The IVGVT will reduce the technical risk of unexpected conditions that could place the vehicle or crew in jeopardy. The Ares Project Office's Flight and Integrated Test Office commissioned a study to determine how historical programs, such as Saturn and Space Shuttle, validated the structural dynamics of an integrated flight vehicle. The study methodology was to examine the historical record and seek out members of the engineering community who recall the development of historic manned launch vehicles. These records and interviews provided insight into the best practices and lessons learned from these historic development programs. The information that was gathered allowed the creation of timelines of the historic development programs. The timelines trace the programs from the development of test articles through test preparation, test operations, and test data reduction efforts. These timelines also demonstrate how the historical tests fit within their overall vehicle development programs. Finally, the study was able to quantify approximate staffing levels during historic development programs. Using this study, the Flight and Integrated Test Office was able to evaluate the Ares I Integrated Vehicle Ground Vibration Test schedule and workforce budgets in light of the historical precedents to determine if the test had schedule or cost risks associated with it.

  14. Podocyte hypertrophy precedes apoptosis under experimental diabetic conditions.

    Science.gov (United States)

    Lee, Sun Ha; Moon, Sung Jin; Paeng, Jisun; Kang, Hye-Young; Nam, Bo Young; Kim, Seonghun; Kim, Chan Ho; Lee, Mi Jung; Oh, Hyung Jung; Park, Jung Tak; Han, Seung Hyeok; Yoo, Tae-Hyun; Kang, Shin-Wook

    2015-08-01

    Podocyte hypertrophy and apoptosis are two hallmarks of diabetic glomeruli, but the sequence in which these processes occur remains a matter of debate. Here we investigated the effects of inhibiting hypertrophy on apoptosis, and vice versa, in both podocytes and glomeruli, under diabetic conditions. Hypertrophy and apoptosis were inhibited using an epidermal growth factor receptor inhibitor (PKI 166) and a pan-caspase inhibitor (zAsp-DCB), respectively. We observed significant increases in the protein expression of p27, p21, phospho-eukaryotic elongation factor 4E-binding protein 1, and phospho-p70 S6 ribosomal protein kinase, in both cultured podocytes exposed to high-glucose (HG) medium, and streptozotocin-induced diabetes mellitus (DM) rat glomeruli. These increases were significantly inhibited by PKI 166, but not by zAsp-DCB. In addition, the amount of protein per cell, the relative cell size, and the glomerular volume were all significantly increased under diabetic conditions, and these changes were also blocked by treatment with PKI 166, but not zAsp-DCB. Increased protein expression of cleaved caspase-3 and cleaved poly (ADP-ribose) polymerase, together with increased Bax/Bcl-2 ratios, were also observed in HG-stimulated podocytes and DM glomeruli. Treatment with either zAsp-DCB or PKI 166 resulted in a significant attenuation of these effects. Both PKI 166 and zAsp-DCB also inhibited the increase in number of apoptotic cells, as assessed by Hoechst 33342 staining and TUNEL assay. Under diabetic conditions, inhibition of podocyte hypertrophy results in attenuated apoptosis, whereas blocking apoptosis has no effect on podocyte hypertrophy, suggesting that podocyte hypertrophy precedes apoptosis.

  15. Pentobarbital anesthesia alters neural responses in the precedence effect.

    Science.gov (United States)

    Song, Penglong; Wang, Ningyu; Wang, Hui; Xie, Yan; Jia, Jun; Li, Huijun

    2011-07-01

    The precedence effect (PE) is thought to be beneficial for proper localization and perception of sounds. The majority of recent physiological studies focus on the neural discharges correlated with PE in the inferior colliculus (IC). Pentobarbital anesthesia is widely used in physiological studies. However, little is known of the effect of pentobarbital on the discharge of neurons in PE. Neuronal responses in the IC from 23 male SD rats were recorded by standard extracellular recording techniques following presentation of 4 ms white noise bursts, presented from either or both of two loud speakers, at different interstimulus delays (ISDs). The neural responses were recorded for off-line analysis before or after intraperitoneal administration of pentobarbital at a loading or maintenance dose. Data were assessed by one-way repeated measures analysis of variance and pairwise comparisons. When the ipsilateral stimuli were leading, pentobarbital at a loading dose significantly increased normal