A robust indicator based on singular value decomposition for flaw feature detection from noisy ultrasonic signals

NASA Astrophysics Data System (ADS)

Cui, Ximing; Wang, Zhe; Kang, Yihua; Pu, Haiming; Deng, Zhiyang

2018-05-01

Singular value decomposition (SVD) has been proven to be an effective de-noising tool for flaw echo signal feature detection in ultrasonic non-destructive evaluation (NDE). However, the uncertainty in the arbitrary manner of the selection of an effective singular value weakens the robustness of this technique. Improper selection of effective singular values will lead to bad performance of SVD de-noising. What is more, the computational complexity of SVD is too large for it to be applied in real-time applications. In this paper, to eliminate the uncertainty in SVD de-noising, a novel flaw indicator, named the maximum singular value indicator (MSI), based on short-time SVD (STSVD), is proposed for flaw feature detection from a measured signal in ultrasonic NDE. In this technique, the measured signal is first truncated into overlapping short-time data segments to put feature information of a transient flaw echo signal in local field, and then the MSI can be obtained from the SVD of each short-time data segment. Research shows that this indicator can clearly indicate the location of ultrasonic flaw signals, and the computational complexity of this STSVD-based indicator is significantly reduced with the algorithm proposed in this paper. Both simulation and experiments show that this technique is very efficient for real-time application in flaw detection from noisy data.

Gaussian fitting for carotid and radial artery pressure waveforms: comparison between normal subjects and heart failure patients.

PubMed

Liu, Chengyu; Zheng, Dingchang; Zhao, Lina; Liu, Changchun

2014-01-01

It has been reported that Gaussian functions could accurately and reliably model both carotid and radial artery pressure waveforms (CAPW and RAPW). However, the physiological relevance of the characteristic features from the modeled Gaussian functions has been little investigated. This study thus aimed to determine characteristic features from the Gaussian functions and to make comparisons of them between normal subjects and heart failure patients. Fifty-six normal subjects and 51 patients with heart failure were studied with the CAPW and RAPW signals recorded simultaneously. The two signals were normalized first and then modeled by three positive Gaussian functions, with their peak amplitude, peak time, and half-width determined. Comparisons of these features were finally made between the two groups. Results indicated that the peak amplitude of the first Gaussian curve was significantly decreased in heart failure patients compared with normal subjects (P<0.001). Significantly increased peak amplitude of the second Gaussian curves (P<0.001) and significantly shortened peak times of the second and third Gaussian curves (both P<0.001) were also presented in heart failure patients. These results were true for both CAPW and RAPW signals, indicating the clinical significance of the Gaussian modeling, which should provide essential tools for further understanding the underlying physiological mechanisms of the artery pressure waveform.

Image processing based automatic diagnosis of glaucoma using wavelet features of segmented optic disc from fundus image.

PubMed

Singh, Anushikha; Dutta, Malay Kishore; ParthaSarathi, M; Uher, Vaclav; Burget, Radim

2016-02-01

Glaucoma is a disease of the retina which is one of the most common causes of permanent blindness worldwide. This paper presents an automatic image processing based method for glaucoma diagnosis from the digital fundus image. In this paper wavelet feature extraction has been followed by optimized genetic feature selection combined with several learning algorithms and various parameter settings. Unlike the existing research works where the features are considered from the complete fundus or a sub image of the fundus, this work is based on feature extraction from the segmented and blood vessel removed optic disc to improve the accuracy of identification. The experimental results presented in this paper indicate that the wavelet features of the segmented optic disc image are clinically more significant in comparison to features of the whole or sub fundus image in the detection of glaucoma from fundus image. Accuracy of glaucoma identification achieved in this work is 94.7% and a comparison with existing methods of glaucoma detection from fundus image indicates that the proposed approach has improved accuracy of classification. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Prognostic significance of MRI findings in patients with myxoid-round cell liposarcoma.

PubMed

Tateishi, Ukihide; Hasegawa, Tadashi; Beppu, Yasuo; Kawai, Akira; Satake, Mitsuo; Moriyama, Noriyuki

2004-03-01

The aims of this study were to determine the prognostic significance of MRI findings in patients with myxoid-round cell liposarcomas and to clarify which MRI features best indicate tumors with adverse clinical behavior. The initial MRI studies of 36 pathologically confirmed myxoid-round cell liposarcomas were retrospectively reviewed, and observations from this review were correlated with the histopathologic features. MR images were evaluated by two radiologists with agreement by consensus, and both univariate and multivariate analyses were conducted to evaluate survival with a median clinical follow-up of 33 months (range, 9-276 months). Statistically significant MRI findings that favored a diagnosis of intermediate- or high-grade tumor were large tumor size (> 10 cm), deeply situated tumor, tumor possessing irregular contours, absence of lobulation, absence of thin septa, presence of thick septa, absence of tumor capsule, high-intensity signal pattern, pronounced enhancement, and globular or nodular enhancement. Of these MRI findings, thin septa (p < 0.05), a tumor capsule (p < 0.01), and pronounced enhancement (p < 0.01) were associated significantly, according to univariate analysis, with overall survival. Multivariate analysis indicated that pronounced enhancement was associated significantly with overall survival (p < 0.05). Contrast-enhanced MRI findings can indicate a good or adverse prognosis in patients with myxoid-round cell liposarcomas.

Identifying Features of Bodily Expression As Indicators of Emotional Experience during Multimedia Learning

PubMed Central

Riemer, Valentin; Frommel, Julian; Layher, Georg; Neumann, Heiko; Schrader, Claudia

2017-01-01

The importance of emotions experienced by learners during their interaction with multimedia learning systems, such as serious games, underscores the need to identify sources of information that allow the recognition of learners’ emotional experience without interrupting the learning process. Bodily expression is gaining in attention as one of these sources of information. However, to date, the question of how bodily expression can convey different emotions has largely been addressed in research relying on acted emotion displays. Following a more contextualized approach, the present study aims to identify features of bodily expression (i.e., posture and activity of the upper body and the head) that relate to genuine emotional experience during interaction with a serious game. In a multimethod approach, 70 undergraduates played a serious game relating to financial education while their bodily expression was captured using an off-the-shelf depth-image sensor (Microsoft Kinect). In addition, self-reports of experienced enjoyment, boredom, and frustration were collected repeatedly during gameplay, to address the dynamic changes in emotions occurring in educational tasks. Results showed that, firstly, the intensities of all emotions indeed changed significantly over the course of the game. Secondly, by using generalized estimating equations, distinct features of bodily expression could be identified as significant indicators for each emotion under investigation. A participant keeping their head more turned to the right was positively related to frustration being experienced, whereas keeping their head more turned to the left was positively related to enjoyment. Furthermore, having their upper body positioned more closely to the gaming screen was also positively related to frustration. Finally, increased activity of a participant’s head emerged as a significant indicator of boredom being experienced. These results confirm the value of bodily expression as an indicator of emotional experience in multimedia learning systems. Furthermore, the findings may guide developers of emotion recognition procedures by focusing on the identified features of bodily expression. PMID:28798717

Classification of interstitial lung disease patterns with topological texture features

NASA Astrophysics Data System (ADS)

Huber, Markus B.; Nagarajan, Mahesh; Leinsinger, Gerda; Ray, Lawrence A.; Wismüller, Axel

2010-03-01

Topological texture features were compared in their ability to classify morphological patterns known as 'honeycombing' that are considered indicative for the presence of fibrotic interstitial lung diseases in high-resolution computed tomography (HRCT) images. For 14 patients with known occurrence of honey-combing, a stack of 70 axial, lung kernel reconstructed images were acquired from HRCT chest exams. A set of 241 regions of interest of both healthy and pathological (89) lung tissue were identified by an experienced radiologist. Texture features were extracted using six properties calculated from gray-level co-occurrence matrices (GLCM), Minkowski Dimensions (MDs), and three Minkowski Functionals (MFs, e.g. MF.euler). A k-nearest-neighbor (k-NN) classifier and a Multilayer Radial Basis Functions Network (RBFN) were optimized in a 10-fold cross-validation for each texture vector, and the classification accuracy was calculated on independent test sets as a quantitative measure of automated tissue characterization. A Wilcoxon signed-rank test was used to compare two accuracy distributions and the significance thresholds were adjusted for multiple comparisons by the Bonferroni correction. The best classification results were obtained by the MF features, which performed significantly better than all the standard GLCM and MD features (p < 0.005) for both classifiers. The highest accuracy was found for MF.euler (97.5%, 96.6%; for the k-NN and RBFN classifier, respectively). The best standard texture features were the GLCM features 'homogeneity' (91.8%, 87.2%) and 'absolute value' (90.2%, 88.5%). The results indicate that advanced topological texture features can provide superior classification performance in computer-assisted diagnosis of interstitial lung diseases when compared to standard texture analysis methods.

Machine learning classifier using abnormal brain network topological metrics in major depressive disorder.

PubMed

Guo, Hao; Cao, Xiaohua; Liu, Zhifen; Li, Haifang; Chen, Junjie; Zhang, Kerang

2012-12-05

Resting state functional brain networks have been widely studied in brain disease research. However, it is currently unclear whether abnormal resting state functional brain network metrics can be used with machine learning for the classification of brain diseases. Resting state functional brain networks were constructed for 28 healthy controls and 38 major depressive disorder patients by thresholding partial correlation matrices of 90 regions. Three nodal metrics were calculated using graph theory-based approaches. Nonparametric permutation tests were then used for group comparisons of topological metrics, which were used as classified features in six different algorithms. We used statistical significance as the threshold for selecting features and measured the accuracies of six classifiers with different number of features. A sensitivity analysis method was used to evaluate the importance of different features. The result indicated that some of the regions exhibited significantly abnormal nodal centralities, including the limbic system, basal ganglia, medial temporal, and prefrontal regions. Support vector machine with radial basis kernel function algorithm and neural network algorithm exhibited the highest average accuracy (79.27 and 78.22%, respectively) with 28 features (P<0.05). Correlation analysis between feature importance and the statistical significance of metrics was investigated, and the results revealed a strong positive correlation between them. Overall, the current study demonstrated that major depressive disorder is associated with abnormal functional brain network topological metrics and statistically significant nodal metrics can be successfully used for feature selection in classification algorithms.

External facial features modify the representation of internal facial features in the fusiform face area.

PubMed

Axelrod, Vadim; Yovel, Galit

2010-08-15

Most studies of face identity have excluded external facial features by either removing them or covering them with a hat. However, external facial features may modify the representation of internal facial features. Here we assessed whether the representation of face identity in the fusiform face area (FFA), which has been primarily studied for internal facial features, is modified by differences in external facial features. We presented faces in which external and internal facial features were manipulated independently. Our findings show that the FFA was sensitive to differences in external facial features, but this effect was significantly larger when the external and internal features were aligned than misaligned. We conclude that the FFA generates a holistic representation in which the internal and the external facial features are integrated. These results indicate that to better understand real-life face recognition both external and internal features should be included. Copyright (c) 2010 Elsevier Inc. All rights reserved.

Application of remote sensing in the study of vegetation and soils in Idaho

NASA Technical Reports Server (NTRS)

Tisdale, E. W. (Principal Investigator)

1973-01-01

The author has identified the following significant results. Comparison of ERTS-1 imagery and USGS 1:250,000 scale maps of study areas with known ground points revealed significant map errors. These errors were sufficient to render impractical the projection of ERTS-1 imagery directly onto maps of the area. Marked differences were found in the delineation of ground features by different MSS bands. Generally, Band 4 was least useful, while Band 5 proved valuable for indicating patterns of native vegetation, cultivated areas - both dry and irrigated, lava fields, drainage basins, and deep bodies of water. Band 6 was better for landforms and drainages and for shallow bodies of water than Band 5 but inferior for indicating patterns in native vegetation and most types of cultivated land. Band 7 was best of all for indicating lava flows, water bodies, and landform features. Use of a additive color viewer-projector aided greatly in separation of images. A combination of Bands 5 and 7 with appropriate color filters proved best for separating most types of native vegetation and cultivated crops. Landform features and water bodies also showed well with this combination. The addition of Band 4 imagery to these further enhanced the identification of semi-dormant vegetation.

Ferric iron in primitive asteroids - A 0.43-micron absorption feature

NASA Technical Reports Server (NTRS)

Vilas, Faith; Hatch, Erin C.; Larson, Stephen M.; Sawyer, Scott R.; Gaffey, Michael J.

1993-01-01

A search of reflectance spectra of C- P-, D- and S-class asteroids to hunt for the Soret band near 0.4 micron that is indicative of porphyrins yielded an identification of an 0.43 micron absorption feature in 11 primitive asteroids of the C, P, and G classes and in one S-class asteroid. It is proposed that the feature is an Fe(3+) spin-forbidden transition in aqueously altered material, possibly located near 0.43 micron due to an enhancement effect similar to the mechanism operating in jarosite. The significance of the feature for the aqueous alteration history of these asteroids is addressed.

A Pilot Study of the Attractive Features of Active Videogames Among Chinese Primary School Children.

PubMed

Lau, Patrick W C; Lau, Erica Y; Wang, Jing Jing; Choi, Cheong-Rak; Kim, Chang Gyun

2017-04-01

The present study (1) explored the attractive features that affect Chinese primary school children's preferences of active videogames (AVGs) and (2) contrasted these findings with those in the Western literature. A total of 22 Chinese primary school children were recruited and interviewed. Four AVGs (Wii "Boxing," "Wii Fit™ Plus Obstacle Run"; "EyeToy Knockout", "EyeToy Keep ups") from two commercial consoles (Nintendo® Wii™ and Sony PlayStation ® 2 "EyeToy ® ") were employed. Participants used four selected AVGs for 3 minutes each. After each play period, children (1) described the strengths and weaknesses of each game as well as rated the attractive features of each game based on a 16-item questionnaire and (2) rated up to 5 items that were most influential regarding their AVG preferences. Participants indicated that control was the most significant feature, followed by feedback, goal, and graphics. The top five rated features imply that the perception of competence was the most appealing aspect and expected outcome of Chinese children who play AVGs. Compared with the Western findings regarding attractive AVG features, the present study found certain similarities as well as significant differences among Chinese AVG players. Based on the present study, control, feedback, goal, and graphics are the most significant features that attract Chinese children to play AVGs. Physical exertion, social interaction, competition, and learning outcomes, which are valued according to Western studies, were not mentioned as significant features by Chinese children. These findings demonstrate a need to investigate the effect of cultural background in AVG study design.

A study of the utilization of ERTS-1 data from the Wabash River Basin

NASA Technical Reports Server (NTRS)

Landgrebe, D. A. (Principal Investigator)

1973-01-01

The author has identified the following significant results. Nine projects are defined, five ERTS data applications experiments and four supporting technology tasks. The most significant applications results were achieved in the soil association mapping, earth surface feature identification, and urban land use mapping efforts. Four soil association boundaries were accurately delineated from ERTS-1 imagery. A data bank has been developed to test surface feature classifications obtained from ERTS-1 data. Preliminary forest cover classifications indicated that the number of acres estimated tended to be greater than actually existed by 25%. Urban land use analysis of ERTS-1 data indicated highly accurate classification could be obtained for many urban catagories. The wooded residential category tended to be misclassified as woods or agricultural land. Further statistical analysis revealed that these classes could be separated using sample variance.

Perception of suprasegmental features of speech by children with cochlear implants and children with hearing AIDS.

PubMed

Most, Tova; Peled, Miriam

2007-01-01

This study assessed perception of suprasegmental features of speech by 30 prelingual children with sensorineural hearing loss. Ten children had cochlear implants (CIs), and 20 children wore hearing aids (HA): 10 with severe hearing loss and 10 with profound hearing loss. Perception of intonation, syllable stress, word emphasis, and word pattern was assessed. Results revealed that the two HA groups significantly outperformed the CI group in perceiving both intonation and stress. Within each group, word pattern was perceived best, and then intonation and emphasis, with syllable stress perceived poorest. No significant correlation emerged between age at implantation and perception of the various suprasegmental features, possibly due to participants' relatively late age at implantation. Results indicated that CI use did not show an advantage over HA use in the perception of suprasegmental features of speech. Future research should continue to explore variables that might improve this perception.

The Roles of Featural and Configural Face Processing in Snap Judgments of Sexual Orientation

PubMed Central

Tabak, Joshua A.; Zayas, Vivian

2012-01-01

Research has shown that people are able to judge sexual orientation from faces with above-chance accuracy, but little is known about how these judgments are formed. Here, we investigated the importance of well-established face processing mechanisms in such judgments: featural processing (e.g., an eye) and configural processing (e.g., spatial distance between eyes). Participants judged sexual orientation from faces presented for 50 milliseconds either upright, which recruits both configural and featural processing, or upside-down, when configural processing is strongly impaired and featural processing remains relatively intact. Although participants judged women’s and men’s sexual orientation with above-chance accuracy for upright faces and for upside-down faces, accuracy for upside-down faces was significantly reduced. The reduced judgment accuracy for upside-down faces indicates that configural face processing significantly contributes to accurate snap judgments of sexual orientation. PMID:22629321

A comparative analysis of user preference-based and existing knowledge management systems attributes in the aerospace industry

NASA Astrophysics Data System (ADS)

Varghese, Nishad G.

Knowledge management (KM) exists in various forms throughout organizations. Process documentation, training courses, and experience sharing are examples of KM activities performed daily. The goal of KM systems (KMS) is to provide a tool set which serves to standardize the creation, sharing, and acquisition of business critical information. Existing literature provides numerous examples of targeted evaluations of KMS, focusing on specific system attributes. This research serves to bridge the targeted evaluations with an industry-specific, holistic approach. The user preferences of aerospace employees in engineering and engineering-related fields were compared to profiles of existing aerospace KMS based on three attribute categories: technical features, system administration, and user experience. The results indicated there is a statistically significant difference between aerospace user preferences and existing profiles in the user experience attribute category, but no statistically significant difference in the technical features and system administration attribute categories. Additional analysis indicated in-house developed systems exhibit higher technical features and user experience ratings than commercial-off-the-self (COTS) systems.

Cytological features of "noninvasive follicular thyroid neoplasm with papillary-like nuclear features" and their correlation with tumor histology.

PubMed

Maletta, Francesca; Massa, Federica; Torregrossa, Liborio; Duregon, Eleonora; Casadei, Gian Piero; Basolo, Fulvio; Tallini, Giovanni; Volante, Marco; Nikiforov, Yuri E; Papotti, Mauro

2016-08-01

Among thyroid papillary carcinomas (PTCs), the follicular variant is the most common and includes encapsulated forms (EFVPTCs). Noninvasive EFVPTCs have very low risk of recurrence or other adverse events and have been recently proposed to be designated as noninvasive follicular thyroid neoplasm with papillary-like nuclear features or NIFTP, thus eliminating the term carcinoma. This proposal is expected to significantly impact the risk of malignancy associated with the currently used diagnostic categories of thyroid cytology. In this study, we analyzed the fine needle aspiration biopsy (FNAB) cytology features of 96 histologically proven NIFTPs and determined how the main nuclear features of NIFTP correlate between cytological and histological samples. Blind review of FNAB cytology from NIFTP nodules yielded the diagnosis of "follicular neoplasm" (Bethesda category IV) in 56% of cases, "suspicious for malignancy" (category V) in 27%, "atypia of undetermined significance/follicular lesion of undetermined significance" (category III) in 15%, and "malignant" (category VI) in 2%. We found good correlation (κ=0.62) of nuclear features between histological and cytological specimens. NIFTP nuclear features (size, irregularities of contours, and chromatin clearing) were significantly different from those of benign nodules but not from those of invasive EFVPTC. Our data indicate that most of the NIFTP nodules yield an indeterminate cytological diagnosis in FNAB cytology and nuclear features found in cytology samples are reproducibly identified in corresponding histology samples. Because of the overlapping nuclear features with invasive EFVPTC, NIFTP cannot be reliably diagnosed preoperatively but should be listed in differential diagnosis of all indeterminate categories of thyroid cytology. Copyright © 2016 Elsevier Inc. All rights reserved.

Feature bindings endure without attention: evidence from an explicit recall task.

PubMed

Gajewski, Daniel A; Brockmole, James R

2006-08-01

Are integrated objects the unit of capacity of visual working memory, or is continued attention needed to maintain bindings between independently stored features? In a delayed recall task, participants reported the color and shape of a probed item from a memory array. During the delay, attention was manipulated with an exogenous cue. Recall was elevated at validly cued positions, indicating that the cue affected item memory. On invalid trials, participants most frequently recalled either both features (perfect object memory) or neither of the two features (no object memory); the frequency with which only one feature was recalled was significantly lower than predicted by feature independence as determined in a single-feature recall task. These data do not support the view that features are remembered independently when attention is withdrawn. Instead, integrated objects are stored in visual working memory without need for continued attention.

Changes in selected features of a male face and assessment of their influence on facial recognition.

PubMed

Lewandowski, Zdzisław

2011-01-01

The project aimed at finding the answers to the following two research questions: --To what extent does a change in size, height or width of the selected face feature influence the assessment of likeness between an original composite portrait and a modified one? --How does the sex of a person who judges the images have an impact on the perception of likeness of the face features? The results indicate that there are significant differences in the assessment of likeness of the portraits with some features modified to the original ones. The images with changes in size and height of the nose received the lowest scores on the likeness scale, which indicates that these changes were perceived by the subjects as the most important. The photos with changes in height and width of the lips, and height and width of the eye slit, in turn, received high scores of likeness, in spite of big changes. This signifies that these modifications were perceived to be of the least importance (compared to the other features investigated).

TU-D-207B-02: Delta-Radiomics: The Prognostic Value of Therapy-Induced Changes in Radiomics Features for Stage III Non-Small Cell Lung Cancer Patients

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fave, X; Court, L; UT Health Science Center, Graduate School of Biomedical Sciences, Houston, TX

Purpose: To determine how radiomics features change during radiation therapy and whether those changes (delta-radiomics features) can improve prognostic models built with clinical factors. Methods: 62 radiomics features, including histogram, co-occurrence, run-length, gray-tone difference, and shape features, were calculated from pretreatment and weekly intra-treatment CTs for 107 stage III NSCLC patients (5–9 images per patient). Image preprocessing for each feature was determined using the set of pretreatment images: bit-depth resample and/or a smoothing filter were tested for their impact on volume-correlation and significance of each feature in univariate cox regression models to maximize their information content. Next, the optimized featuresmore » were calculated from the intratreatment images and tested in linear mixed-effects models to determine which features changed significantly with dose-fraction. The slopes in these significant features were defined as delta-radiomics features. To test their prognostic potential multivariate cox regression models were fitted, first using only clinical features and then clinical+delta-radiomics features for overall-survival, local-recurrence, and distant-metastases. Leave-one-out cross validation was used for model-fitting and patient predictions. Concordance indices(c-index) and p-values for the log-rank test with patients stratified at the median were calculated. Results: Approximately one-half of the 62 optimized features required no preprocessing, one-fourth required smoothing, and one-fourth required smoothing and resampling. From these, 54 changed significantly during treatment. For overall-survival, the c-index improved from 0.52 for clinical factors alone to 0.62 for clinical+delta-radiomics features. For distant-metastases, the c-index improved from 0.53 to 0.58, while for local-recurrence it did not improve. Patient stratification significantly improved (p-value<0.05) for overallsurvival and distant-metastases when delta-radiomics features were included. The delta-radiomics versions of autocorrelation, kurtosis, and compactness were selected most frequently in leave-one-out iterations. Conclusion: Weekly changes in radiomics features can potentially be used to evaluate treatment response and predict patient outcomes. High-risk patients could be recommended for dose escalation or consolidation chemotherapy. This project was funded in part by grants from the National Cancer Institute (NCI) and the Cancer Prevention Research Institute of Texas (CPRIT).« less

Radiomics-based Prognosis Analysis for Non-Small Cell Lung Cancer

NASA Astrophysics Data System (ADS)

Zhang, Yucheng; Oikonomou, Anastasia; Wong, Alexander; Haider, Masoom A.; Khalvati, Farzad

2017-04-01

Radiomics characterizes tumor phenotypes by extracting large numbers of quantitative features from radiological images. Radiomic features have been shown to provide prognostic value in predicting clinical outcomes in several studies. However, several challenges including feature redundancy, unbalanced data, and small sample sizes have led to relatively low predictive accuracy. In this study, we explore different strategies for overcoming these challenges and improving predictive performance of radiomics-based prognosis for non-small cell lung cancer (NSCLC). CT images of 112 patients (mean age 75 years) with NSCLC who underwent stereotactic body radiotherapy were used to predict recurrence, death, and recurrence-free survival using a comprehensive radiomics analysis. Different feature selection and predictive modeling techniques were used to determine the optimal configuration of prognosis analysis. To address feature redundancy, comprehensive analysis indicated that Random Forest models and Principal Component Analysis were optimum predictive modeling and feature selection methods, respectively, for achieving high prognosis performance. To address unbalanced data, Synthetic Minority Over-sampling technique was found to significantly increase predictive accuracy. A full analysis of variance showed that data endpoints, feature selection techniques, and classifiers were significant factors in affecting predictive accuracy, suggesting that these factors must be investigated when building radiomics-based predictive models for cancer prognosis.

Landsat analysis for uranium exploration in Northeast Turkey

USGS Publications Warehouse

Lee, Keenan

1983-01-01

No uranium deposits are known in the Trabzon, Turkey region, and consequently, exploration criteria have not been defined. Nonetheless, by analogy with uranium deposits studied elsewhere, exploration guides are suggested to include dense concentrations of linear features, lineaments -- especially with northwest trend, acidic plutonic rocks, and alteration indicated by limonite. A suite of digitally processed images of a single Landsat scene served as the image base for mapping 3,376 linear features. Analysis of the linear feature data yielded two statistically significant trends, which in turn defined two sets of strong lineaments. Color composite images were used to map acidic plutonic rocks and areas of surficial limonitic materials. The Landsat interpretation yielded a map of these exploration guides that may be used to evaluate relative uranium potential. One area in particular shows a high coincidence of favorable indicators.

Airborne spectrophotometry of Comet Halley from 5 to 9 microns

NASA Technical Reports Server (NTRS)

Campins, H.; Bregman, J. D.; Witteborn, F. C.; Wooden, D. H.; Rank, D. M.; Cohen, M.; Allamandola, Louis J.; Tielens, Alexander G. G. M.

1986-01-01

Spectrophotometry from 5 to 9 microns (resolution = 0.02) of comet Halley was obtained from the Kuiper Airborne Observatory on 1985 Dec. 12.1 and 1986 April 8.6 and 10.5 UT. Two spectral features are apparent in all the observations, one from 5.24 to 5.6 microns, and the silicate emission feature which has an onset between 7 and 8 microns. There is no evidence for the 7.5 microns feature observed by the Vega 1 spacecraft; the large difference between the areal coverage viewed from the spacecraft and the airplane may explain the discrepancy. Color temperatures significantly higher than a blackbody indicate that small particles are abundant in the coma. Significant spatial and temporal variations in the spectrum show trends similar to those observed from the ground.

Hallucinations: A Systematic Review of Points of Similarity and Difference Across Diagnostic Classes

PubMed Central

Waters, Flavie; Fernyhough, Charles

2017-01-01

Hallucinations constitute one of the 5 symptom domains of psychotic disorders in DSM-5, suggesting diagnostic significance for that group of disorders. Although specific featural properties of hallucinations (negative voices, talking in the third person, and location in external space) are no longer highlighted in DSM, there is likely a residual assumption that hallucinations in schizophrenia can be identified based on these candidate features. We investigated whether certain featural properties of hallucinations are specifically indicative of schizophrenia by conducting a systematic review of studies showing direct comparisons of the featural and clinical characteristics of (auditory and visual) hallucinations among 2 or more population groups (one of which included schizophrenia). A total of 43 articles were reviewed, which included hallucinations in 4 major groups (nonclinical groups, drug- and alcohol-related conditions, medical and neurological conditions, and psychiatric disorders). The results showed that no single hallucination feature or characteristic uniquely indicated a diagnosis of schizophrenia, with the sole exception of an age of onset in late adolescence. Among the 21 features of hallucinations in schizophrenia considered here, 95% were shared with other psychiatric disorders, 85% with medical/neurological conditions, 66% with drugs and alcohol conditions, and 52% with the nonclinical groups. Additional differences rendered the nonclinical groups somewhat distinctive from clinical disorders. Overall, when considering hallucinations, it is inadvisable to give weight to the presence of any featural properties alone in making a schizophrenia diagnosis. It is more important to focus instead on the co-occurrence of other symptoms and the value of hallucinations as an indicator of vulnerability. PMID:27872259

Camera trap placement and the potential for bias due to trails and other features

PubMed Central

Forrester, Tavis D.

2017-01-01

Camera trapping has become an increasingly widespread tool for wildlife ecologists, with large numbers of studies relying on photo capture rates or presence/absence information. It is increasingly clear that camera placement can directly impact this kind of data, yet these biases are poorly understood. We used a paired camera design to investigate the effect of small-scale habitat features on species richness estimates, and capture rate and detection probability of several mammal species in the Shenandoah Valley of Virginia, USA. Cameras were deployed at either log features or on game trails with a paired camera at a nearby random location. Overall capture rates were significantly higher at trail and log cameras compared to their paired random cameras, and some species showed capture rates as much as 9.7 times greater at feature-based cameras. We recorded more species at both log (17) and trail features (15) than at their paired control cameras (13 and 12 species, respectively), yet richness estimates were indistinguishable after 659 and 385 camera nights of survey effort, respectively. We detected significant increases (ranging from 11–33%) in detection probability for five species resulting from the presence of game trails. For six species detection probability was also influenced by the presence of a log feature. This bias was most pronounced for the three rodents investigated, where in all cases detection probability was substantially higher (24.9–38.2%) at log cameras. Our results indicate that small-scale factors, including the presence of game trails and other features, can have significant impacts on species detection when camera traps are employed. Significant biases may result if the presence and quality of these features are not documented and either incorporated into analytical procedures, or controlled for in study design. PMID:29045478

Camera trap placement and the potential for bias due to trails and other features.

PubMed

Kolowski, Joseph M; Forrester, Tavis D

2017-01-01

Camera trapping has become an increasingly widespread tool for wildlife ecologists, with large numbers of studies relying on photo capture rates or presence/absence information. It is increasingly clear that camera placement can directly impact this kind of data, yet these biases are poorly understood. We used a paired camera design to investigate the effect of small-scale habitat features on species richness estimates, and capture rate and detection probability of several mammal species in the Shenandoah Valley of Virginia, USA. Cameras were deployed at either log features or on game trails with a paired camera at a nearby random location. Overall capture rates were significantly higher at trail and log cameras compared to their paired random cameras, and some species showed capture rates as much as 9.7 times greater at feature-based cameras. We recorded more species at both log (17) and trail features (15) than at their paired control cameras (13 and 12 species, respectively), yet richness estimates were indistinguishable after 659 and 385 camera nights of survey effort, respectively. We detected significant increases (ranging from 11-33%) in detection probability for five species resulting from the presence of game trails. For six species detection probability was also influenced by the presence of a log feature. This bias was most pronounced for the three rodents investigated, where in all cases detection probability was substantially higher (24.9-38.2%) at log cameras. Our results indicate that small-scale factors, including the presence of game trails and other features, can have significant impacts on species detection when camera traps are employed. Significant biases may result if the presence and quality of these features are not documented and either incorporated into analytical procedures, or controlled for in study design.

Comparison of conventional and automated breast volume ultrasound in the description and characterization of solid breast masses based on BI-RADS features.

PubMed

Kim, Hyunji; Cha, Joo Hee; Oh, Ha-Yeun; Kim, Hak Hee; Shin, Hee Jung; Chae, Eun Young

2014-07-01

To compare the performance of radiologists in the use of conventional ultrasound (US) and automated breast volume ultrasound (ABVU) for the characterization of benign and malignant solid breast masses based on breast imaging and reporting data system (BI-RADS) criteria. Conventional US and ABVU images were obtained in 87 patients with 106 solid breast masses (52 cancers, 54 benign lesions). Three experienced radiologists who were blinded to all examination results independently characterized the lesions and reported a BI-RADS assessment category and a level of suspicion of malignancy. The results were analyzed by calculation of Cohen's κ coefficient and by receiver operating characteristic (ROC) analysis. Assessment of the agreement of conventional US and ABVU indicated that the posterior echo feature was the most discordant feature of seven features (κ = 0.371 ± 0.225) and that orientation had the greatest agreement (κ = 0.608 ± 0.210). The final assessment showed substantial agreement (κ = 0.773 ± 0.104). The areas under the ROC curves (Az) for conventional US and ABVU were not statistically significant for each reader, but the mean Az values of conventional US and ABVU by multi-reader multi-case analysis were significantly different (conventional US 0.991, ABVU 0.963; 95 % CI -0.0471 to -0.0097). The means for sensitivity, specificity, positive predictive value, and negative predictive value of conventional US and ABVU did not differ significantly. There was substantial inter-observer agreement in the final assessment of solid breast masses by conventional US and ABVU. ROC analysis comparing the performance of conventional US and ABVU indicated a marginally significant difference in mean Az, but not in mean sensitivity, specificity, positive predictive value, or negative predictive value.

Brain Responses to Musical Feature Changes in Adolescent Cochlear Implant Users

PubMed Central

Petersen, Bjørn; Weed, Ethan; Sandmann, Pascale; Brattico, Elvira; Hansen, Mads; Sørensen, Stine Derdau; Vuust, Peter

2015-01-01

Cochlear implants (CIs) are primarily designed to assist deaf individuals in perception of speech, although possibilities for music fruition have also been documented. Previous studies have indicated the existence of neural correlates of residual music skills in postlingually deaf adults and children. However, little is known about the behavioral and neural correlates of music perception in the new generation of prelingually deaf adolescents who grew up with CIs. With electroencephalography (EEG), we recorded the mismatch negativity (MMN) of the auditory event-related potential to changes in musical features in adolescent CI users and in normal-hearing (NH) age mates. EEG recordings and behavioral testing were carried out before (T1) and after (T2) a 2-week music training program for the CI users and in two sessions equally separated in time for NH controls. We found significant MMNs in adolescent CI users for deviations in timbre, intensity, and rhythm, indicating residual neural prerequisites for musical feature processing. By contrast, only one of the two pitch deviants elicited an MMN in CI users. This pitch discrimination deficit was supported by behavioral measures, in which CI users scored significantly below the NH level. Overall, MMN amplitudes were significantly smaller in CI users than in NH controls, suggesting poorer music discrimination ability. Despite compliance from the CI participants, we found no effect of the music training, likely resulting from the brevity of the program. This is the first study showing significant brain responses to musical feature changes in prelingually deaf adolescent CI users and their associations with behavioral measures, implying neural predispositions for at least some aspects of music processing. Future studies should test any beneficial effects of a longer lasting music intervention in adolescent CI users. PMID:25705185

Brain responses to musical feature changes in adolescent cochlear implant users.

PubMed

Petersen, Bjørn; Weed, Ethan; Sandmann, Pascale; Brattico, Elvira; Hansen, Mads; Sørensen, Stine Derdau; Vuust, Peter

2015-01-01

Cochlear implants (CIs) are primarily designed to assist deaf individuals in perception of speech, although possibilities for music fruition have also been documented. Previous studies have indicated the existence of neural correlates of residual music skills in postlingually deaf adults and children. However, little is known about the behavioral and neural correlates of music perception in the new generation of prelingually deaf adolescents who grew up with CIs. With electroencephalography (EEG), we recorded the mismatch negativity (MMN) of the auditory event-related potential to changes in musical features in adolescent CI users and in normal-hearing (NH) age mates. EEG recordings and behavioral testing were carried out before (T1) and after (T2) a 2-week music training program for the CI users and in two sessions equally separated in time for NH controls. We found significant MMNs in adolescent CI users for deviations in timbre, intensity, and rhythm, indicating residual neural prerequisites for musical feature processing. By contrast, only one of the two pitch deviants elicited an MMN in CI users. This pitch discrimination deficit was supported by behavioral measures, in which CI users scored significantly below the NH level. Overall, MMN amplitudes were significantly smaller in CI users than in NH controls, suggesting poorer music discrimination ability. Despite compliance from the CI participants, we found no effect of the music training, likely resulting from the brevity of the program. This is the first study showing significant brain responses to musical feature changes in prelingually deaf adolescent CI users and their associations with behavioral measures, implying neural predispositions for at least some aspects of music processing. Future studies should test any beneficial effects of a longer lasting music intervention in adolescent CI users.

Desert landforms of southwest Egypt: A basis for comparison with Mars

NASA Technical Reports Server (NTRS)

El-Baz, F. (Editor); Maxwell, T. A. (Editor)

1982-01-01

Geologic interpretations of The Gilf Kebir-Uweinat of Apollo-Soyuz photographs were verified. The photographs and LANDSAT images showed features reminiscent of those depicted by Mariner and Viking missions to Mars. These features were to better understand their morphologic analogs on Mars. It is indicated that climate change played a significant role in the formation of the eastern Sahara. It is also revealed that correlations between the eolian features in southwestern Egypt and the wind blown patterns on the surface of Mars result in a better understanding of eolian activity on both planets.

The relationship between 2D static features and 2D dynamic features used in gait recognition

NASA Astrophysics Data System (ADS)

Alawar, Hamad M.; Ugail, Hassan; Kamala, Mumtaz; Connah, David

2013-05-01

In most gait recognition techniques, both static and dynamic features are used to define a subject's gait signature. In this study, the existence of a relationship between static and dynamic features was investigated. The correlation coefficient was used to analyse the relationship between the features extracted from the "University of Bradford Multi-Modal Gait Database". This study includes two dimensional dynamic and static features from 19 subjects. The dynamic features were compromised of Phase-Weighted Magnitudes driven by a Fourier Transform of the temporal rotational data of a subject's joints (knee, thigh, shoulder, and elbow). The results concluded that there are eleven pairs of features that are considered significantly correlated with (p<0.05). This result indicates the existence of a statistical relationship between static and dynamics features, which challenges the results of several similar studies. These results bare great potential for further research into the area, and would potentially contribute to the creation of a gait signature using latent data.

Lung texture in serial thoracic CT scans: Assessment of change introduced by image registration1

PubMed Central

Cunliffe, Alexandra R.; Al-Hallaq, Hania A.; Labby, Zacariah E.; Pelizzari, Charles A.; Straus, Christopher; Sensakovic, William F.; Ludwig, Michelle; Armato, Samuel G.

2012-01-01

Purpose: The aim of this study was to quantify the effect of four image registration methods on lung texture features extracted from serial computed tomography (CT) scans obtained from healthy human subjects. Methods: Two chest CT scans acquired at different time points were collected retrospectively for each of 27 patients. Following automated lung segmentation, each follow-up CT scan was registered to the baseline scan using four algorithms: (1) rigid, (2) affine, (3) B-splines deformable, and (4) demons deformable. The registration accuracy for each scan pair was evaluated by measuring the Euclidean distance between 150 identified landmarks. On average, 1432 spatially matched 32 × 32-pixel region-of-interest (ROI) pairs were automatically extracted from each scan pair. First-order, fractal, Fourier, Laws’ filter, and gray-level co-occurrence matrix texture features were calculated in each ROI, for a total of 140 features. Agreement between baseline and follow-up scan ROI feature values was assessed by Bland–Altman analysis for each feature; the range spanned by the 95% limits of agreement of feature value differences was calculated and normalized by the average feature value to obtain the normalized range of agreement (nRoA). Features with small nRoA were considered “registration-stable.” The normalized bias for each feature was calculated from the feature value differences between baseline and follow-up scans averaged across all ROIs in every patient. Because patients had “normal” chest CT scans, minimal change in texture feature values between scan pairs was anticipated, with the expectation of small bias and narrow limits of agreement. Results: Registration with demons reduced the Euclidean distance between landmarks such that only 9% of landmarks were separated by ≥1 mm, compared with rigid (98%), affine (95%), and B-splines (90%). Ninety-nine of the 140 (71%) features analyzed yielded nRoA > 50% for all registration methods, indicating that the majority of feature values were perturbed following registration. Nineteen of the features (14%) had nRoA < 15% following demons registration, indicating relative feature value stability. Student's t-tests showed that the nRoA of these 19 features was significantly larger when rigid, affine, or B-splines registration methods were used compared with demons registration. Demons registration yielded greater normalized bias in feature value change than B-splines registration, though this difference was not significant (p = 0.15). Conclusions: Demons registration provided higher spatial accuracy between matched anatomic landmarks in serial CT scans than rigid, affine, or B-splines algorithms. Texture feature changes calculated in healthy lung tissue from serial CT scans were smaller following demons registration compared with all other algorithms. Though registration altered the values of the majority of texture features, 19 features remained relatively stable after demons registration, indicating their potential for detecting pathologic change in serial CT scans. Combined use of accurate deformable registration using demons and texture analysis may allow for quantitative evaluation of local changes in lung tissue due to disease progression or treatment response. PMID:22894392

A preliminary evaluation of the validity of binge-eating disorder defining features in a community-based sample.

PubMed

Klein, Kelly M; Forney, K Jean; Keel, Pamela K

2016-05-01

Little empirical attention has been paid to the DSM-5 definition of binge-eating disorder (BED), particularly to the associated features of binge episodes. The present study sought to determine how the associated features and undue influence of weight/shape on self-evaluation contribute to evidence of a clinically significant eating disorder. Secondary analyses were conducted on data (N = 80; 76.3% women, 76.3% Caucasian, ages 18-43) collected through an epidemiological study of eating patterns. Descriptive statistics were used to report the sample prevalence of the features, independently and in combination. Correlations and alpha reliability were employed to examine relationships among associated features, distress regarding bingeing, and clinical diagnosis. Regression models and receiver-operating characteristic (ROC) curves were used to determine the utility of the features for explaining variance in distress. Internal consistency reliability for indicators was low, and several features demonstrated low or nonsignificant associations with distress and diagnosis. Feeling disgusted/depressed/guilty was the only unique predictor of distress (p = 0.001). For the ROC curves, three features was the best threshold for predicting distress. Results support the need to refine the features to ensure better detection of clinically significant eating pathology for research inclusion and treatment of the illness. © 2015 Wiley Periodicals, Inc. (Int J Eat Disord 2016; 49:524-528). © 2015 Wiley Periodicals, Inc.

Likelihood ratio-based differentiation of nodular Hashimoto thyroiditis and papillary thyroid carcinoma in patients with sonographically evident diffuse hashimoto thyroiditis: preliminary study.

PubMed

Wang, Liang; Xia, Yu; Jiang, Yu-Xin; Dai, Qing; Li, Xiao-Yi

2012-11-01

To assess the efficacy of sonography for discriminating nodular Hashimoto thyroiditis from papillary thyroid carcinoma in patients with sonographically evident diffuse Hashimoto thyroiditis. This study included 20 patients with 24 surgically confirmed Hashimoto thyroiditis nodules and 40 patients with 40 papillary thyroid carcinoma nodules; all had sonographically evident diffuse Hashimoto thyroiditis. A retrospective review of the sonograms was performed, and significant benign and malignant sonographic features were selected by univariate and multivariate analyses. The combined likelihood ratio was calculated as the product of each feature's likelihood ratio for papillary thyroid carcinoma. We compared the abilities of the original sonographic features and combined likelihood ratios in diagnosing nodular Hashimoto thyroiditis and papillary thyroid carcinoma by their sensitivity, specificity, and Youden index. The diagnostic capabilities of the sonographic features varied greatly, with Youden indices ranging from 0.175 to 0.700. Compared with single features, combinations of features were unable to improve the Youden indices effectively because the sensitivity and specificity usually changed in opposite directions. For combined likelihood ratios, however, the sensitivity improved greatly without an obvious reduction in specificity, which resulted in the maximum Youden index (0.825). With a combined likelihood ratio greater than 7.00 as the diagnostic criterion for papillary thyroid carcinoma, sensitivity reached 82.5%, whereas specificity remained at 100.0%. With a combined likelihood ratio less than 1.00 for nodular Hashimoto thyroiditis, sensitivity and specificity were 90.0% and 92.5%, respectively. Several sonographic features of nodular Hashimoto thyroiditis and papillary thyroid carcinoma in a background of diffuse Hashimoto thyroiditis were significantly different. The combined likelihood ratio may be superior to original sonographic features for discrimination of nodular Hashimoto thyroiditis from papillary thyroid carcinoma; therefore, it is a promising risk index for thyroid nodules and warrants further investigation.

Association between dermoscopic and reflectance confocal microscopy features of cutaneous melanoma with BRAF mutational status.

PubMed

Bombonato, C; Ribero, S; Pozzobon, F C; Puig-Butille, J A; Badenas, C; Carrera, C; Malvehy, J; Moscarella, E; Lallas, A; Piana, S; Puig, S; Argenziano, G; Longo, C

2017-04-01

Melanomas harbouring common genetic mutations might share certain morphological features detectable with dermoscopy and reflectance confocal microscopy. BRAF mutational status is crucial for the management of metastatic melanoma. To correlate the dermoscopic characteristics of primary cutaneous melanomas with BRAF mutational status. Furthermore, a subset of tumours has also been analysed for the presence of possible confocal features that might be linked with BRAF status. Retrospectively acquired dermoscopic and confocal images of patients with melanoma in tertiary referral academic centres: Skin Cancer Unit in Reggio Emilia and at the Melanoma Unit in Barcelona. Kruskal-Wallis test, logistic regressions, univariate and multivariate analyses have been performed to find dermoscopic and confocal features significantly correlated with BRAF mutational status. Dermoscopically, the presence of irregular peripheral streaks and ulceration were positive predictors of BRAF-mutated melanomas with a statistically significance value, while dotted vessels were more represented in wild-type melanomas. None of the evaluated reflectance confocal microscopy features were correlated with genetic profiling. Ulceration and irregular peripheral streaks represent dermoscopic feature indicative for BRAF-mutated melanoma, while dotted vessels are suggestive for wild-type melanoma. © 2016 European Academy of Dermatology and Venereology.

Gender discrimination of eyes and mouths by individuals with autism.

PubMed

Best, Catherine A; Minshew, Nancy J; Strauss, Mark S

2010-04-01

Evidence remains mixed about whether individuals with autism look less to eyes and whether they look more at mouths. Few studies have examined how spontaneous attention to facial features relates to face processing abilities. This study tested the ability to discriminate gender from facial features, namely eyes and mouths, by comparing accuracy scores of 17 children with autism and 15 adults with autism to 17 typically developing children and 15 typically developing adults. Results indicated that all participants regardless of diagnosis discriminated gender more accurately from eyes than from mouths. However, results indicated that compared to adults without autism, adults with autism were significantly worse at discriminating gender from eyes.

Testing for new physics: neutrinos and the primordial power spectrum

DOE Office of Scientific and Technical Information (OSTI.GOV)

Canac, Nicolas; Abazajian, Kevork N.; Aslanyan, Grigor

2016-09-01

We test the sensitivity of neutrino parameter constraints from combinations of CMB and LSS data sets to the assumed form of the primordial power spectrum (PPS) using Bayesian model selection. Significantly, none of the tested combinations, including recent high-precision local measurements of H{sub 0} and cluster abundances, indicate a signal for massive neutrinos or extra relativistic degrees of freedom. For PPS models with a large, but fixed number of degrees of freedom, neutrino parameter constraints do not change significantly if the location of any features in the PPS are allowed to vary, although neutrino constraints are more sensitive to PPSmore » features if they are known a priori to exist at fixed intervals in log k . Although there is no support for a non-standard neutrino sector from constraints on both neutrino mass and relativistic energy density, we see surprisingly strong evidence for features in the PPS when it is constrained with data from Planck 2015, SZ cluster counts, and recent high-precision local measurements of H{sub 0}. Conversely combining Planck with matter power spectrum and BAO measurements yields a much weaker constraint. Given that this result is sensitive to the choice of data this tension between SZ cluster counts, Planck and H{sub 0} measurements is likely an indication of unmodeled systematic bias that mimics PPS features, rather than new physics in the PPS or neutrino sector.« less

Texture analysis of apparent diffusion coefficient maps for treatment response assessment in prostate cancer bone metastases-A pilot study.

PubMed

Reischauer, Carolin; Patzwahl, René; Koh, Dow-Mu; Froehlich, Johannes M; Gutzeit, Andreas

2018-04-01

To evaluate whole-lesion volumetric texture analysis of apparent diffusion coefficient (ADC) maps for assessing treatment response in prostate cancer bone metastases. Texture analysis is performed in 12 treatment-naïve patients with 34 metastases before treatment and at one, two, and three months after the initiation of androgen deprivation therapy. Four first-order and 19 second-order statistical texture features are computed on the ADC maps in each lesion at every time point. Repeatability, inter-patient variability, and changes in the feature values under therapy are investigated. Spearman rank's correlation coefficients are calculated across time to demonstrate the relationship between the texture features and the serum prostate specific antigen (PSA) levels. With few exceptions, the texture features exhibited moderate to high precision. At the same time, Friedman's tests revealed that all first-order and second-order statistical texture features changed significantly in response to therapy. Thereby, the majority of texture features showed significant changes in their values at all post-treatment time points relative to baseline. Bivariate analysis detected significant correlations between the great majority of texture features and the serum PSA levels. Thereby, three first-order and six second-order statistical features showed strong correlations with the serum PSA levels across time. The findings in the present work indicate that whole-tumor volumetric texture analysis may be utilized for response assessment in prostate cancer bone metastases. The approach may be used as a complementary measure for treatment monitoring in conjunction with averaged ADC values. Copyright © 2018 Elsevier B.V. All rights reserved.

Determining local and contextual features describing appearance of difficult to identify mitotic figures

NASA Astrophysics Data System (ADS)

Gandomkar, Ziba; Brennan, Patrick C.; Mello-Thoms, Claudia

2017-03-01

Mitotic count is helpful in determining the aggressiveness of breast cancer. In previous studies, it was shown that the agreement among pathologists for grading mitotic index is fairly modest, as mitoses have a large variety of appearances and they could be mistaken for other similar objects. In this study, we determined local and contextual features that differ significantly between easily identifiable mitoses and challenging ones. The images were obtained from the Mitosis-Atypia 2014 challenge. In total, the dataset contained 453 mitotic figures. Two pathologists annotated each mitotic figure. In case of disagreement, an opinion from a third pathologist was requested. The mitoses were grouped into three categories, those recognized as "a true mitosis" by both pathologists ,those labelled as "a true mitosis" by only one of the first two readers and also the third pathologist, and those annotated as "probably a mitosis" by all readers or the majority of them. After color unmixing, the mitoses were segmented from H channel. Shape-based features along with intensity-based and textural features were extracted from H-channel, blue ratio channel and five different color spaces. Holistic features describing each image were also considered. The Kruskal-Wallis H test was used to identify significantly different features. Multiple comparisons were done using the rank-based version of Tukey-Kramer test. The results indicated that there are local and global features which differ significantly among different groups. In addition, variations between mitoses in different groups were captured in the features from HSL and LCH color space more than other ones.

Computation of reliable textural indices from multimodal brain MRI: suggestions based on a study of patients with diffuse intrinsic pontine glioma

NASA Astrophysics Data System (ADS)

Goya-Outi, Jessica; Orlhac, Fanny; Calmon, Raphael; Alentorn, Agusti; Nioche, Christophe; Philippe, Cathy; Puget, Stéphanie; Boddaert, Nathalie; Buvat, Irène; Grill, Jacques; Frouin, Vincent; Frouin, Frederique

2018-05-01

Few methodological studies regarding widely used textural indices robustness in MRI have been reported. In this context, this study aims to propose some rules to compute reliable textural indices from multimodal 3D brain MRI. Diagnosis and post-biopsy MR scans including T1, post-contrast T1, T2 and FLAIR images from thirty children with diffuse intrinsic pontine glioma (DIPG) were considered. The hybrid white stripe method was adapted to standardize MR intensities. Sixty textural indices were then computed for each modality in different regions of interest (ROI), including tumor and white matter (WM). Three types of intensity binning were compared : constant bin width and relative bounds; constant number of bins and relative bounds; constant number of bins and absolute bounds. The impact of the volume of the region was also tested within the WM. First, the mean Hellinger distance between patient-based intensity distributions decreased by a factor greater than 10 in WM and greater than 2.5 in gray matter after standardization. Regarding the binning strategy, the ranking of patients was highly correlated for 188/240 features when comparing with , but for only 20 when comparing with , and nine when comparing with . Furthermore, when using or texture indices reflected tumor heterogeneity as assessed visually by experts. Last, 41 features presented statistically significant differences between contralateral WM regions when ROI size slightly varies across patients, and none when using ROI of the same size. For regions with similar size, 224 features were significantly different between WM and tumor. Valuable information from texture indices can be biased by methodological choices. Recommendations are to standardize intensities in MR brain volumes, to use intensity binning with constant bin width, and to define regions with the same volumes to get reliable textural indices.

A window-based time series feature extraction method.

PubMed

Katircioglu-Öztürk, Deniz; Güvenir, H Altay; Ravens, Ursula; Baykal, Nazife

2017-10-01

This study proposes a robust similarity score-based time series feature extraction method that is termed as Window-based Time series Feature ExtraCtion (WTC). Specifically, WTC generates domain-interpretable results and involves significantly low computational complexity thereby rendering itself useful for densely sampled and populated time series datasets. In this study, WTC is applied to a proprietary action potential (AP) time series dataset on human cardiomyocytes and three precordial leads from a publicly available electrocardiogram (ECG) dataset. This is followed by comparing WTC in terms of predictive accuracy and computational complexity with shapelet transform and fast shapelet transform (which constitutes an accelerated variant of the shapelet transform). The results indicate that WTC achieves a slightly higher classification performance with significantly lower execution time when compared to its shapelet-based alternatives. With respect to its interpretable features, WTC has a potential to enable medical experts to explore definitive common trends in novel datasets. Copyright © 2017 Elsevier Ltd. All rights reserved.

Predicting Length of Stay for Obstetric Patients via Electronic Medical Records.

PubMed

Gao, Cheng; Kho, Abel N; Ivory, Catherine; Osmundson, Sarah; Malin, Bradley A; Chen, You

2017-01-01

Obstetric care refers to the care provided to patients during ante-, intra-, and postpartum periods. Predicting length of stay (LOS) for these patients during their hospitalizations can assist healthcare organizations in allocating hospital resources more effectively and efficiently, ultimately improving maternal care quality and reducing costs to patients. In this paper, we investigate the extent to which LOS can be forecast from a patient's medical history. We introduce a machine learning framework to incorporate a patient's prior conditions (e.g., diagnostic codes) as features in a predictive model for LOS. We evaluate the framework with three years of historical billing data from the electronic medical records of 9188 obstetric patients in a large academic medical center. The results indicate that our framework achieved an average accuracy of 49.3%, which is higher than the baseline accuracy 37.7% (that relies solely on a patient's age). The most predictive features were found to have statistically significant discriminative ability. These features included billing codes for normal delivery (indicative of shorter stay) and antepartum hypertension (indicative of longer stay).

Hallucinations: A Systematic Review of Points of Similarity and Difference Across Diagnostic Classes.

PubMed

Waters, Flavie; Fernyhough, Charles

2017-01-01

Hallucinations constitute one of the 5 symptom domains of psychotic disorders in DSM-5, suggesting diagnostic significance for that group of disorders. Although specific featural properties of hallucinations (negative voices, talking in the third person, and location in external space) are no longer highlighted in DSM, there is likely a residual assumption that hallucinations in schizophrenia can be identified based on these candidate features. We investigated whether certain featural properties of hallucinations are specifically indicative of schizophrenia by conducting a systematic review of studies showing direct comparisons of the featural and clinical characteristics of (auditory and visual) hallucinations among 2 or more population groups (one of which included schizophrenia). A total of 43 articles were reviewed, which included hallucinations in 4 major groups (nonclinical groups, drug- and alcohol-related conditions, medical and neurological conditions, and psychiatric disorders). The results showed that no single hallucination feature or characteristic uniquely indicated a diagnosis of schizophrenia, with the sole exception of an age of onset in late adolescence. Among the 21 features of hallucinations in schizophrenia considered here, 95% were shared with other psychiatric disorders, 85% with medical/neurological conditions, 66% with drugs and alcohol conditions, and 52% with the nonclinical groups. Additional differences rendered the nonclinical groups somewhat distinctive from clinical disorders. Overall, when considering hallucinations, it is inadvisable to give weight to the presence of any featural properties alone in making a schizophrenia diagnosis. It is more important to focus instead on the co-occurrence of other symptoms and the value of hallucinations as an indicator of vulnerability. © The Author 2016. Published by Oxford University Press on behalf of the Maryland Psychiatric Research Center.

Measurement and evolution of the thickness distribution and morphology of deformed features of Antarctic sea ice

NASA Astrophysics Data System (ADS)

Tin, Tina

Antarctic sea ice thickness data obtained from drilling on sea ice floes were examined with the goal of enhancing our capability to estimate ice thickness remotely, especially from air- or space-borne altimetry and shipboard visual observations. The state of hydrostatic equilibrium of deformed ice features and the statistical relationships between ice thickness and top surface roughness were examined. Results indicate that ice thickness may be estimated fairly reliably from surface measurements of snow elevation on length scales of ≥100 m. Examination of the morphology of deformed ice features show that Antarctic pressure ridges are flatter and less massive than Arctic pressure ridges and that not all surface features (ridge sails) are associated with features underwater (ridge keels). I propose that the differences in morphology are due to differences in sampling strategies, parent ice characteristics and the magnitude and duration of driving forces. As a result of these findings, the existing methodology used to estimate ice thickness from shipboard visual observations was modified to incorporate the probability that a sail is associated with a keel underwater, and the probability that keels may be found under level surfaces. Using the improved methodology, ice thickness was estimated from ship observations data obtained during two cruises in the Ross Sea, Antarctica. The dynamic and thermodynamic processes involved in the development of the ice prior to their observation were examined employing a regional sea ice-mixed layer-pycnocline model. Both our model results and previously published ice core data indicate that thermodynamic thickening is the dominant process that determines the thickness of first year ice in the central Ross Sea, although dynamic thickening also plays a significant role. Ice core data also indicate that snow ice forms a significant proportion of the total ice mass. For ice in the northeast Ross Sea in the summer, model results and evidence from ice core and oceanographic data indicate that dynamic thickening, snow ice formation and bottom melting compete to determine the ice thickness during mid and late winter.

Collaborative Brain-Computer Interface for Aiding Decision-Making

PubMed Central

Poli, Riccardo; Valeriani, Davide; Cinel, Caterina

2014-01-01

We look at the possibility of integrating the percepts from multiple non-communicating observers as a means of achieving better joint perception and better group decisions. Our approach involves the combination of a brain-computer interface with human behavioural responses. To test ideas in controlled conditions, we asked observers to perform a simple matching task involving the rapid sequential presentation of pairs of visual patterns and the subsequent decision as whether the two patterns in a pair were the same or different. We recorded the response times of observers as well as a neural feature which predicts incorrect decisions and, thus, indirectly indicates the confidence of the decisions made by the observers. We then built a composite neuro-behavioural feature which optimally combines the two measures. For group decisions, we uses a majority rule and three rules which weigh the decisions of each observer based on response times and our neural and neuro-behavioural features. Results indicate that the integration of behavioural responses and neural features can significantly improve accuracy when compared with the majority rule. An analysis of event-related potentials indicates that substantial differences are present in the proximity of the response for correct and incorrect trials, further corroborating the idea of using hybrids of brain-computer interfaces and traditional strategies for improving decision making. PMID:25072739

Comparison of demons deformable registration-based methods for texture analysis of serial thoracic CT scans

NASA Astrophysics Data System (ADS)

Cunliffe, Alexandra R.; Al-Hallaq, Hania A.; Fei, Xianhan M.; Tuohy, Rachel E.; Armato, Samuel G.

2013-02-01

To determine how 19 image texture features may be altered by three image registration methods, "normal" baseline and follow-up computed tomography (CT) scans from 27 patients were analyzed. Nineteen texture feature values were calculated in over 1,000 32x32-pixel regions of interest (ROIs) randomly placed in each baseline scan. All three methods used demons registration to map baseline scan ROIs to anatomically matched locations in the corresponding transformed follow-up scan. For the first method, the follow-up scan transformation was subsampled to achieve a voxel size identical to that of the baseline scan. For the second method, the follow-up scan was transformed through affine registration to achieve global alignment with the baseline scan. For the third method, the follow-up scan was directly deformed to the baseline scan using demons deformable registration. Feature values in matched ROIs were compared using Bland- Altman 95% limits of agreement. For each feature, the range spanned by the 95% limits was normalized to the mean feature value to obtain the normalized range of agreement, nRoA. Wilcoxon signed-rank tests were used to compare nRoA values across features for the three methods. Significance for individual tests was adjusted using the Bonferroni method. nRoA was significantly smaller for affine-registered scans than for the resampled scans (p=0.003), indicating lower feature value variability between baseline and follow-up scan ROIs using this method. For both of these methods, however, nRoA was significantly higher than when feature values were calculated directly on demons-deformed followup scans (p<0.001). Across features and methods, nRoA values remained below 26%.

Predicting neo-adjuvant chemotherapy response and progression-free survival of locally advanced breast cancer using textural features of intratumoral heterogeneity on F-18 FDG PET/CT and diffusion-weighted MR imaging.

PubMed

Yoon, Hai-Jeon; Kim, Yemi; Chung, Jin; Kim, Bom Sahn

2018-03-30

Predicting response to neo-adjuvant chemotherapy (NAC) and survival in locally advanced breast cancer (LABC) is important. This study investigated the prognostic value of tumor heterogeneity evaluated with textural analysis through F-18 fluorodeoxyglucose (FDG) positron emission tomography (PET) and diffusion-weighted imaging (DWI). We enrolled 83 patients with LABC who had completed NAC and curative surgery. Tumor texture indices from pretreatment FDG PET and DWI were extracted from histogram analysis and 7 different parent matrices: co-occurrence matrix, the voxel-alignment matrix, neighborhood intensity difference matrix, intensity size-zone matrix (ISZM), normalized gray-level co-occurrence matrix (NGLCM), neighboring gray-level dependence matrix (NGLDM), and texture spectrum matrix. The predictive values of textural features were tested regarding both pathologic NAC response and progression-free survival. Among 83 patients, 46 were pathologic responders, while 37 were nonresponders. The PET texture indices from 7 parent matrices, DWI texture indices from histogram, and 1 parent matrix (NGLCM) showed significant differences according to NAC response. On multivariable analysis, number nonuniformity of PET extracted from the NGLDM was an independent predictor of pathologic response (P = .009). During a median follow-up period of 17.3 months, 14 patients experienced recurrence. High-intensity zone emphasis (HIZE) and high-intensity short-zone emphasis (HISZE) from PET extracted from ISZM were significant textural predictors (P = .011 and P = .033). On Cox regression analysis, only HIZE was a significant predictor of recurrence (P = .027), while HISZE showed borderline significance (P = .107). Tumor texture indices are useful for NAC response prediction in LABC. Moreover, PET texture indices can help to predict disease recurrence. © 2018 Wiley Periodicals, Inc.

Borderline Personality Disorder Features in Nonclinical Young Adults: 2. Two-Year Outcome

PubMed Central

Trull, Timothy J.; Useda, J. David; Conforti, Kelly; Doan, Bao-Tran

2013-01-01

Borderline personality disorder (BPD) is thought to develop by early adulthood, and it is characterized by lack of control of anger, intense and frequent mood changes, impulsive acts, disturbed interpersonal relationships, and life-threatening behaviors. We describe data from a 2-year follow-up study of nonclinical young adults who, at study entry, exhibited a significant number of BPD features. Individuals with borderline features were more likely to have academic difficulties over the succeeding 2 years, and these participants were more likely to meet lifetime criteria for a mood disorder and to experience interpersonal dysfunction than their peers at the 2-year follow-up assessment. These findings indicate that BPD features are associated with poorer outcome even within a nonclinical population. PMID:9131850

Prognostic discrimination in "good-risk" chronic granulocytic leukemia.

PubMed

Sokal, J E; Cox, E B; Baccarani, M; Tura, S; Gomez, G A; Robertson, J E; Tso, C Y; Braun, T J; Clarkson, B D; Cervantes, F

1984-04-01

The prognostic significance of disease features recorded at the time of diagnosis was examined among 813 patients with Philadelphia chromosome-positive, nonblastic chronic granulocytic leukemia (CGL) collected from six European and American series. The survival pattern for this population was typical of "good-risk" patients, and median survival was 47 mo. There were multiple interrelationships among different disease features, which led to highly significant correlations with survival for some that had no primary prognostic significance, such as hematocrit. Multivariable regression analysis indicated that spleen size and the percentage of circulating blasts were the most important prognostic indicators. These features, and age, behaved as continuous variables with progressively unfavorable import at higher values. The platelet count did not influence survival significantly at values below 700 X 10(9)/liter but was increasingly unfavorable above this level. Basophils plus eosinophils over 15%, more than 5% marrow blasts, and karyotypic abnormalities in addition to the Ph1 were also significant unfavorable signs. The Cox model, generated with four variables representing percent blasts, spleen size, platelet count, and age, provided a useful representation of risk status in this population, with good fit between predicted and observed survival over more than a twofold survival range. A hazard function derived from half of the patient population successfully segregated the remainder into three groups with significantly different survival patterns. We conclude that it should be possible to identify a lower risk group of patients with a 2-yr survival of 90%, subsequent risk averaging somewhat less than 20%/yr and median survival of 5 yr, an intermediate group, and a high-risk group with a 2-yr survival of 65%, followed by a death rate of about 35%/yr and median survival of 2.5 yr.

An investigation to improve the Menhaden fishery prediction and detection model through the application of ERTS-A data

NASA Technical Reports Server (NTRS)

Maughan, P. M. (Principal Investigator)

1972-01-01

The author has identified the following significant results. Preliminary analyses indicate that several important relationships have been observed utilizing ERTS-1 imagery. Of most significance is that in the Mississippi Sound, as elsewhere, considerable detail exists as to turbidity patterns in the water column. Simple analysis is complicated by the apparent interaction between actual turbidity, turbidity induced by shoal water, and actual imaging of the bottom in extreme shoal water. A statistical approach is being explored which shows promise of at least partially separating these effects so that partitioning of true turbid plumes can be accomplished. This partitioning is of great importance to this program in that supportive data seem to indicate that menhaden occur more frequently in turbid areas. In this connection four individual captures have been associated with a major turbid feature imaged on 6 August. If a significant relationship between imaged turbid features and catch distribution can be established, for example by graphic and/or numeric analysis, it will represent a major advancement for short term prediction of commercially accessible menhaden.

Significance of the impact of motion compensation on the variability of PET image features

NASA Astrophysics Data System (ADS)

Carles, M.; Bach, T.; Torres-Espallardo, I.; Baltas, D.; Nestle, U.; Martí-Bonmatí, L.

2018-03-01

In lung cancer, quantification by positron emission tomography/computed tomography (PET/CT) imaging presents challenges due to respiratory movement. Our primary aim was to study the impact of motion compensation implied by retrospectively gated (4D)-PET/CT on the variability of PET quantitative parameters. Its significance was evaluated by comparison with the variability due to (i) the voxel size in image reconstruction and (ii) the voxel size in image post-resampling. The method employed for feature extraction was chosen based on the analysis of (i) the effect of discretization of the standardized uptake value (SUV) on complementarity between texture features (TF) and conventional indices, (ii) the impact of the segmentation method on the variability of image features, and (iii) the variability of image features across the time-frame of 4D-PET. Thirty-one PET-features were involved. Three SUV discretization methods were applied: a constant width (SUV resolution) of the resampling bin (method RW), a constant number of bins (method RN) and RN on the image obtained after histogram equalization (method EqRN). The segmentation approaches evaluated were 40% of SUVmax and the contrast oriented algorithm (COA). Parameters derived from 4D-PET images were compared with values derived from the PET image obtained for (i) the static protocol used in our clinical routine (3D) and (ii) the 3D image post-resampled to the voxel size of the 4D image and PET image derived after modifying the reconstruction of the 3D image to comprise the voxel size of the 4D image. Results showed that TF complementarity with conventional indices was sensitive to the SUV discretization method. In the comparison of COA and 40% contours, despite the values not being interchangeable, all image features showed strong linear correlations (r  >  0.91, p\\ll 0.001 ). Across the time-frames of 4D-PET, all image features followed a normal distribution in most patients. For our patient cohort, the compensation of tumor motion did not have a significant impact on the quantitative PET parameters. The variability of PET parameters due to voxel size in image reconstruction was more significant than variability due to voxel size in image post-resampling. In conclusion, most of the parameters (apart from the contrast of neighborhood matrix) were robust to the motion compensation implied by 4D-PET/CT. The impact on parameter variability due to the voxel size in image reconstruction and in image post-resampling could not be assumed to be equivalent.

10 CFR 60.122 - Siting criteria.

Code of Federal Regulations, 2011 CFR

2011-01-01

... Period. (12) Earthquakes which have occurred historically that if they were to be repeated could affect the site significantly. (13) Indications, based on correlations of earthquakes with tectonic processes and features, that either the frequency of occurrence or magnitude of earthquakes may increase. (14...

10 CFR 60.122 - Siting criteria.

Code of Federal Regulations, 2014 CFR

2014-01-01

... Period. (12) Earthquakes which have occurred historically that if they were to be repeated could affect the site significantly. (13) Indications, based on correlations of earthquakes with tectonic processes and features, that either the frequency of occurrence or magnitude of earthquakes may increase. (14...

10 CFR 60.122 - Siting criteria.

Code of Federal Regulations, 2012 CFR

2012-01-01

... Period. (12) Earthquakes which have occurred historically that if they were to be repeated could affect the site significantly. (13) Indications, based on correlations of earthquakes with tectonic processes and features, that either the frequency of occurrence or magnitude of earthquakes may increase. (14...

10 CFR 60.122 - Siting criteria.

Code of Federal Regulations, 2013 CFR

2013-01-01

... Period. (12) Earthquakes which have occurred historically that if they were to be repeated could affect the site significantly. (13) Indications, based on correlations of earthquakes with tectonic processes and features, that either the frequency of occurrence or magnitude of earthquakes may increase. (14...

[Landscape pattern gradient dynamics and desakota features in rapid urbanization area: a case study in Panyu of Guangzhou].

PubMed

Yu, Long-Sheng; Fu, Yi-Fu; Yu, Huai-Yi; Li, Zhi-Qin

2011-01-01

In order to understand the landscape pattern gradient dynamics and desakota features in rapid urbanization area, this paper took the rapidly urbanizing Panyu District of Guangzhou City as a case, and analyzed its land use and land cover data, based on four Landsat TM images from 1990 to 2008. With the combination of gradient analysis and landscape pattern analysis, and by using the landscape indices in both class and landscape scales, the spatial dynamics and desakota feature of this rapidly urbanizing district were quantified. In the study district, there was a significant change in the landscape pattern, and a typical desakota feature presented along buffer gradient zones. Urban landscape increased and expanded annually, accompanied with serious fragmentation of agricultural landscape. The indices patch density, contagion, and landscape diversity, etc., changed regularly in the urbanization gradient, and the peak of landscape indices appeared in the gradient zone of 4-6 km away from the urban center. The landscape patterns at time series also reflected the differences among the dynamics in different gradient zones. The landscape pattern in desakota region was characterized by complex patch shape, high landscape diversity and fragmentation, and remarkable landscape dynamics. The peaks of landscape indices spread from the urban center to border areas, and desakota region was expanding gradually. The general trend of spatiotemporal dynamics in desakota region and its driving forces were discussed, which could be benefit to the regional land use policy-making and sustainable development planning.

Response Assessment and Prediction in Esophageal Cancer Patients via F-18 FDG PET/CT Scans

NASA Astrophysics Data System (ADS)

Higgins, Kyle J.

Purpose: The purpose of this study is to utilize F-18 FDG PET/CT scans to determine an indicator for the response of esophageal cancer patients during radiation therapy. There is a need for such an indicator since local failures are quite common in esophageal cancer patients despite modern treatment techniques. If an indicator is found, a patient's treatment strategy may be altered to possibly improve the outcome. This is investigated with various standard uptake volume (SUV) metrics along with image texture features. The metrics and features showing the most promise and indicating response are used in logistic regression analysis to find an equation for the prediction of response. Materials and Methods: 28 patients underwent F-18 FDG PET/CT scans prior to the start of radiation therapy (RT). A second PET/CT scan was administered following the delivery of ~32 Gray (Gy) of dose. A physician contoured gross tumor volume (GTV) was used to delineate a PET based GTV (GTV-pre-PET) based on a threshold of >40% and >20% of the maximum SUV value in the GTV. Deformable registration was used in VelocityAI software to register the pre-treatment and intra-treatment CT scans so that the GTV-pre-PET contours could be transferred from the pre to intra scans (GTV-intra-PET). The fractional decrease in the maximum, mean, volume to the highest intensity 10%-90%, and combination SUV metrics of the significant previous SUV metrics were compared to post-treatment pathologic response for an indication of response. Next for the >40% threshold, texture features based on a neighborhood gray-tone dimension matrix (NGTDM) were analyzed. The fractional decrease in coarseness, contrast, busyness, complexity, and texture strength were compared to the pathologic response of the patients. From these previous two types of analysis, SUV and texture features, the two most significant results were used in logistic regression analysis to find an equation to predict the probability of a non-responder. These probability values were then used to compare against the pathological response to test for indication of response. Results: 20 of the 28 patients underwent post treatment surgery and their pathologic response was determined. 9 of the patients were classified as being responders (treatment effect grade ≤ 1) while 11 of the patients were classified as being non-responders (treatment effect grade > 1). The fractional difference in the different SUV metrics has shown that the most commonly used maximum SUV and mean SUV were not significant in determining response to the treatment. Other SUV metrics however did show promise as being indicators. For the >40% threshold SUV to the highest 10%, 20%, and 30% (SUV10%, SUV20%, SUV30%) were found to significantly distinguish between responders and non-responders (p=0.004) and had an area under the Receiver Operating Characteristic curve (AUC) of 0.7778. Combining these significant metrics (SUV10% with SUV20% and SUV 20% with SUV30%) also was able to distinguish response (p=0.033, AUC=0.7879). Cross validation of these results shown that these metrics could be used to find the response on previously unseen data. The three individual SUV terms distinguished responders from non-responders with a sensitivity of 0.7143 and a specificity of 0.6400 from the cross validation. Cross validation yielded a sensitivity of 0.8333 and a specificity of 0.7727 for the combination of SUV10% and SUV20% and a sensitivity of 0.8333 and specificity of 0.7273 for the combination of SUV20% and SUV30%. For the >20% threshold two SUV metrics were found to be significant. These were the SUV to the highest 10% and 20% (p=0.0048). The AUC for the 10% metrics was 0.7677 and for the 20% metric it was 0.7374. Cross validation of these two metrics shown that the 10% metric was the better indicator with being able to distinguish response in unseen data with a sensitivity of 0.7778 and a specificity of 0.7727. The only texture feature that was able to determine response was complexity (p-0.04, AUC=0.7778). This metric was no more significant than the three individual SUV metrics but less significant than both of the combination metrics. As with the SUV metrics, cross validation was able to show the robustness of these results. Cross validation yielded a result that could accurately distinguish a response with a sensitivity of 0.8333 and a specificity of 0.7273. Logistic regression fit with features of the two most significant results (complexity and combination of SUV10% with SUV20%) yielded the most significant result (p=0.004. AUC=0.8889). Cross validation of this model resulted in a sensitivity of 0.7982 and a specificity 0.7940. This shows that the model would accurately predict the response to unseen data. Conclusions: This study revealed that previously used SUV metrics, maximum and mean SUV, may have to be rethought about being used to determine a response in esophageal cancer patients. The most promising SUV metric was a combination of the SUV10% and SUV20% metric for a GTV created from a threshold of >40% of the maximum SUV value, while the most significant texture feature was complexity. The overall best indicator was the logistic regression fit of the significant metrics of complexity and combination of SUV10% with SUV20%. This was able to distinguish responders from non-responders with a threshold of 0.3186 (sensitivity=0.9091, specificity=0.7778).

Body condition of the deep water demersal resources at two adjacent oligotrophic areas of the western Mediterranean and the influence of the environmental features

NASA Astrophysics Data System (ADS)

Rueda, L.; Moranta, J.; Abelló, P.; Balbín, R.; Barberá, C.; Fernández de Puelles, M. L.; Olivar, M. P.; Ordines, F.; Ramón, M.; Torres, A. P.; Valls, M.; Massutí, E.

2014-10-01

Body condition indices not only are often used as reliable indicators of the nutritional status of individuals but also can they be utilized to provide insights regarding food availability and habitat quality. The aim of this study was to evaluate the connection between the body condition of the demersal species and the environmental features in the water column (i.e. the hydrographic conditions and the potential trophic resources) in two proximate areas, the north and south regions of the Balearic Islands (western Mediterranean), viz., the Balearic sub-basin (BsB) and the Algerian sub-basin (AsB), respectively, with different geomorphological and hydrodynamic features. Body condition indices were calculated for individuals of 21 demersal species including 11 teleosts, 4 elasmobranchs, 3 cephalopods and 3 crustaceans, which represented > 70-77% of the deep water resources, captured by bottom trawling. The morphometric indices, viz., Relative Condition Index (Kn) and Standardised Residuals (SR) from the length-weight relationship, were used. The results for each one of the 21 species indicated a significantly better condition in terms of Kn and SR in the BsB, for 7 and 9 species, respectively. In addition, a general model, including the 21 species together, showed better body condition in the BsB, and during the summer. The spatial and temporal differences in the body condition are discussed in the context of the environmental variables characterising both the study areas, which showed significant variations, for some of the hydrographic features (chlorophyll a, dissolved oxygen, salinity, potential density and temperature), as well as for some of the potential trophic resources (mesopelagic and epibenthic fauna). These findings suggest an environmental effect on the body condition of the deep-water resources in the Balearic Islands, one of the most oligotrophic areas of the western Mediterranean, and reveal more suitable environmental conditions for these species on the northern insular margin, off the Archipelago. In addition to these ecological connections, the results also hold interest for the management and conservation of the habitats essential for the sustainability of fisheries.

Fast detection of covert visuospatial attention using hybrid N2pc and SSVEP features

NASA Astrophysics Data System (ADS)

Xu, Minpeng; Wang, Yijun; Nakanishi, Masaki; Wang, Yu-Te; Qi, Hongzhi; Jung, Tzyy-Ping; Ming, Dong

2016-12-01

Objective. Detecting the shift of covert visuospatial attention (CVSA) is vital for gaze-independent brain-computer interfaces (BCIs), which might be the only communication approach for severely disabled patients who cannot move their eyes. Although previous studies had demonstrated that it is feasible to use CVSA-related electroencephalography (EEG) features to control a BCI system, the communication speed remains very low. This study aims to improve the speed and accuracy of CVSA detection by fusing EEG features of N2pc and steady-state visual evoked potential (SSVEP). Approach. A new paradigm was designed to code the left and right CVSA with the N2pc and SSVEP features, which were then decoded by a classification strategy based on canonical correlation analysis. Eleven subjects were recruited to perform an offline experiment in this study. Temporal waves, amplitudes, and topographies for brain responses related to N2pc and SSVEP were analyzed. The classification accuracy derived from the hybrid EEG features (SSVEP and N2pc) was compared with those using the single EEG features (SSVEP or N2pc). Main results. The N2pc could be significantly enhanced under certain conditions of SSVEP modulations. The hybrid EEG features achieved significantly higher accuracy than the single features. It obtained an average accuracy of 72.9% by using a data length of 400 ms after the attention shift. Moreover, the average accuracy reached ˜80% (peak values above 90%) when using 2 s long data. Significance. The results indicate that the combination of N2pc and SSVEP is effective for fast detection of CVSA. The proposed method could be a promising approach for implementing a gaze-independent BCI.

Unsupervised Pattern Classifier for Abnormality-Scaling of Vibration Features for Helicopter Gearbox Fault Diagnosis

NASA Technical Reports Server (NTRS)

Jammu, Vinay B.; Danai, Kourosh; Lewicki, David G.

1996-01-01

A new unsupervised pattern classifier is introduced for on-line detection of abnormality in features of vibration that are used for fault diagnosis of helicopter gearboxes. This classifier compares vibration features with their respective normal values and assigns them a value in (0, 1) to reflect their degree of abnormality. Therefore, the salient feature of this classifier is that it does not require feature values associated with faulty cases to identify abnormality. In order to cope with noise and changes in the operating conditions, an adaptation algorithm is incorporated that continually updates the normal values of the features. The proposed classifier is tested using experimental vibration features obtained from an OH-58A main rotor gearbox. The overall performance of this classifier is then evaluated by integrating the abnormality-scaled features for detection of faults. The fault detection results indicate that the performance of this classifier is comparable to the leading unsupervised neural networks: Kohonen's Feature Mapping and Adaptive Resonance Theory (AR72). This is significant considering that the independence of this classifier from fault-related features makes it uniquely suited to abnormality-scaling of vibration features for fault diagnosis.

Usability issues concerning child restraint system harness design.

PubMed

Rudin-Brown, Christina M; Kumagai, Jason K; Angel, Harry A; Iwasa-Madge, Kim M; Noy, Y Ian

2003-05-01

A study was conducted to assess usability issues relating to child restraint system (CRS) harness design. Four convertible child restraint systems representing a wide variety of design features were used. Forty-two participants installed two child test dummies in both forward- and rear-facing configurations either inside or outside a test vehicle. Observer-scored checklists determined the degree to which each harness was installed correctly. Participant-scored questionnaires evaluated the 'ease-of-use' of various design features. While the percentage of correct installations exceeded 83% for all designs when installed in the forward-facing configuration, in the rear-facing position (that intended for children under 9-10 kg), there was a significant (between 65 and 89%) percentage of incorrect installations for all models. This finding is of particular interest and may be indicative of a more generalized problem with 'convertible' CRS designs when they are used in the rear-facing configuration. Furthermore, while certain design features were perceived by users as providing significantly better protection in the event of a collision, these also tended to be the features that were misused most often. The benefits and costs of various design features are discussed, and a method to test harness design usability is presented.

V-ELMpiRNAPred: Identification of human piRNAs by the voting-based extreme learning machine (V-ELM) with a new hybrid feature.

PubMed

Pian, Cong; Chen, Yuan-Yuan; Zhang, Jin; Chen, Zhi; Zhang, Guang-Le; Li, Qiang; Yang, Tao; Zhang, Liang-Yun

2017-02-01

Piwi-interacting RNAs (piRNAs) were recently discovered as endogenous small noncoding RNAs. Some recent research suggests that piRNAs may play an important role in cancer. So the precise identification of human piRNAs is a significant work. In this paper, we introduce a series of new features with 80 dimension called short sequence motifs (SSM). A hybrid feature vector with 1444 dimension can be formed by combining 1364 features of [Formula: see text]-mer strings and 80 features of SSM features. We optimize the 1444 dimension features using the feature score criterion (FSC) and list them in descending order according to the scores. The first 462 are selected as the input feature vector in the classifier. Moreover, eight of 80 SSM features appear in the top 20. This indicates that these eight SSM features play an important part in the identification of piRNAs. Since five of the above eight SSM features are associated with nucleotide A and G ('A*G', 'A**G', 'A***G', 'A****G', 'A*****G'). So, we guess there may exist some biological significance. We also use a neural network algorithm called voting-based extreme learning machine (V-ELM) to identify real piRNAs. The Specificity (Sp) and Sensitivity (Sn) of our method are 95.48% and 94.61%, respectively in human species. This result shows that our method is more effective compared with those of the piRPred, piRNApredictor, Asym-Pibomd, Piano and McRUMs. The web service of V-ELMpiRNAPred is available for free at http://mm20132014.wicp.net:38601/velmprepiRNA/Main.jsp .

Brain functional network connectivity based on a visual task: visual information processing-related brain regions are significantly activated in the task state.

PubMed

Yang, Yan-Li; Deng, Hong-Xia; Xing, Gui-Yang; Xia, Xiao-Luan; Li, Hai-Fang

2015-02-01

It is not clear whether the method used in functional brain-network related research can be applied to explore the feature binding mechanism of visual perception. In this study, we investigated feature binding of color and shape in visual perception. Functional magnetic resonance imaging data were collected from 38 healthy volunteers at rest and while performing a visual perception task to construct brain networks active during resting and task states. Results showed that brain regions involved in visual information processing were obviously activated during the task. The components were partitioned using a greedy algorithm, indicating the visual network existed during the resting state. Z-values in the vision-related brain regions were calculated, confirming the dynamic balance of the brain network. Connectivity between brain regions was determined, and the result showed that occipital and lingual gyri were stable brain regions in the visual system network, the parietal lobe played a very important role in the binding process of color features and shape features, and the fusiform and inferior temporal gyri were crucial for processing color and shape information. Experimental findings indicate that understanding visual feature binding and cognitive processes will help establish computational models of vision, improve image recognition technology, and provide a new theoretical mechanism for feature binding in visual perception.

Root features related to plant growth and nutrient removal of 35 wetland plants.

PubMed

Lai, Wen-Ling; Wang, Shu-Qiang; Peng, Chang-Lian; Chen, Zhang-He

2011-07-01

Morphological, structural, and eco-physiological features of roots, nutrient removal, and correlation between the indices were comparatively studied for 35 emergent wetland plants in small-scale wetlands for further investigation into the hypothesis of two types of wetland plant roots (Chen et al., 2004). Significant differences in root morphological, structural, and eco-physiological features were found among the 35 species. They were divided into two types: fibrous-root plants and thick-root plants. The fibrous-root plants had most or all roots of diameter (D) ≤ 1 mm. Roots of D > 1 mm also had many fine and long lateral roots of D ≤ 1 mm. The roots of these plants were long and had a thin epidermis and a low degree of lignification. The roots of the thick-root plants were almost all thicker than 1 mm, and generally had no further fine lateral roots. The roots were short, smooth, and fleshy, and had a thick epidermis. Root porosity of the fibrous-root plants was higher than that of the thick-root plants (p = 0.001). The aerenchyma of the fibrous-root plants was composed of large cavities which were formed from many small cavities, and distributed radially between the exodermis and vascular tissues. The aerenchyma of the thick-root plants had a large number of small cavities which were distributed in the mediopellis. The fibrous-root plants had a significantly larger root biomass of D ≤ 1 mm, of 1 mm < D < 3 mm, above-ground biomass, total biomass, and longer root system, but shorter root longevity than those of the thick-root plants (p = 0.003, 0.018, 0.020, 0.032, 0.042, 0.001). The fibrous-root plants also had significantly higher radial oxygen loss (ROL), root activity, photosynthetic rate, transpiration rate, and removal rates of total nitrogen and total phosphorus than the thick-root plants (p = 0.001, 0.008, 0.010, 0.004, 0.020, 0.002). The results indicate that significantly different root morphological and structural features existed among different wetland plants, and these features had a close relationship to nutrient removal capacity. Copyright © 2011 Elsevier Ltd. All rights reserved.

YamiPred: A Novel Evolutionary Method for Predicting Pre-miRNAs and Selecting Relevant Features.

PubMed

Kleftogiannis, Dimitrios; Theofilatos, Konstantinos; Likothanassis, Spiros; Mavroudi, Seferina

2015-01-01

MicroRNAs (miRNAs) are small non-coding RNAs, which play a significant role in gene regulation. Predicting miRNA genes is a challenging bioinformatics problem and existing experimental and computational methods fail to deal with it effectively. We developed YamiPred, an embedded classification method that combines the efficiency and robustness of support vector machines (SVM) with genetic algorithms (GA) for feature selection and parameters optimization. YamiPred was tested in a new and realistic human dataset and was compared with state-of-the-art computational intelligence approaches and the prevalent SVM-based tools for miRNA prediction. Experimental results indicate that YamiPred outperforms existing approaches in terms of accuracy and of geometric mean of sensitivity and specificity. The embedded feature selection component selects a compact feature subset that contributes to the performance optimization. Further experimentation with this minimal feature subset has achieved very high classification performance and revealed the minimum number of samples required for developing a robust predictor. YamiPred also confirmed the important role of commonly used features such as entropy and enthalpy, and uncovered the significance of newly introduced features, such as %A-U aggregate nucleotide frequency and positional entropy. The best model trained on human data has successfully predicted pre-miRNAs to other organisms including the category of viruses.

Mathematics teachers' conceptions about modelling activities and its reflection on their beliefs about mathematics

NASA Astrophysics Data System (ADS)

Shahbari, Juhaina Awawdeh

2018-07-01

The current study examines whether the engagement of mathematics teachers in modelling activities and subsequent changes in their conceptions about these activities affect their beliefs about mathematics. The sample comprised 52 mathematics teachers working in small groups in four modelling activities. The data were collected from teachers' Reports about features of each activity, interviews and questionnaires on teachers' beliefs about mathematics. The findings indicated changes in teachers' conceptions about the modelling activities. Most teachers referred to the first activity as a mathematical problem but emphasized only the mathematical notions or the mathematical operations in the modelling process; changes in their conceptions were gradual. Most of the teachers referred to the fourth activity as a mathematical problem and emphasized features of the whole modelling process. The results of the interviews indicated that changes in the teachers' conceptions can be attributed to structure of the activities, group discussions, solution paths and elicited models. These changes about modelling activities were reflected in teachers' beliefs about mathematics. The quantitative findings indicated that the teachers developed more constructive beliefs about mathematics after engagement in the modelling activities and that the difference was significant, however there was no significant difference regarding changes in their traditional beliefs.

[18]Fluorodeoxyglucose Positron Emission Tomography for the Textural Features of Cervical Cancer Associated with Lymph Node Metastasis and Histological Type.

PubMed

Shen, Wei-Chih; Chen, Shang-Wen; Liang, Ji-An; Hsieh, Te-Chun; Yen, Kuo-Yang; Kao, Chia-Hung

2017-09-01

In this study, we investigated the correlation between the lymph node (LN) status or histological types and textural features of cervical cancers on 18 F-fluorodeoxyglucose positron emission tomography/computed tomography. We retrospectively reviewed the imaging records of 170 patients with International Federation of Gynecology and Obstetrics stage IB-IVA cervical cancer. Four groups of textural features were studied in addition to the maximum standardized uptake value (SUV max ), metabolic tumor volume, and total lesion glycolysis (TLG). Moreover, we studied the associations between the indices and clinical parameters, including the LN status, clinical stage, and histology. Receiver operating characteristic curves were constructed to evaluate the optimal predictive performance among the various textural indices. Quantitative differences were determined using the Mann-Whitney U test. Multivariate logistic regression analysis was performed to determine the independent factors, among all the variables, for predicting LN metastasis. Among all the significant indices related to pelvic LN metastasis, homogeneity derived from the gray-level co-occurrence matrix (GLCM) was the sole independent predictor. By combining SUV max , the risk of pelvic LN metastasis can be scored accordingly. The TLG mean was the independent feature of positive para-aortic LNs. Quantitative differences between squamous and nonsquamous histology can be determined using short-zone emphasis (SZE) from the gray-level size zone matrix (GLSZM). This study revealed that in patients with cervical cancer, pelvic or para-aortic LN metastases can be predicted by using textural feature of homogeneity from the GLCM and TLG mean, respectively. SZE from the GLSZM is the sole feature associated with quantitative differences between squamous and nonsquamous histology.

Variations in lithospheric thickness on Venus

NASA Technical Reports Server (NTRS)

Johnson, C. L.; Sandwell, David T.

1992-01-01

Recent analyses of Magellan data have indicated many regions exhibiting topograhic flexure. On Venus, flexure is associated predominantly with coronae and the chasmata with Aphrodite Terra. Modeling of these flexural signatures allows the elastic and mechanical thickness of the lithosphere to be estimated. In areas where the lithosphere is flexed beyond its elastic limit the saturation moment provides information on the strength of the lithosphere. Modeling of 12 flexural features on Venus has indicated lithospheric thicknesses comparable with terrestrial values. This has important implications for the venusian heat budget. Flexure of a thin elastic plate due simultaneously to a line load on a continuous plate and a bending moment applied to the end of a broken plate is considered. The mean radius and regional topographic gradient are also included in the model. Features with a large radius of curvature were selected so that a two-dimensional approximation could be used. Comparisons with an axisymmetric model were made for some features to check the validity of the two-dimensional assumption. The best-fit elastic thickness was found for each profile crossing a given flexural feature. In addition, the surface stress and bending moment at the first zero crossing of each profile were also calculated. Flexural amplitudes and elastic thicknesses obtained for 12 features vary significantly. Three examples of the model fitting procedures are discussed.

Classification of pulmonary pathology from breath sounds using the wavelet packet transform and an extreme learning machine.

PubMed

Palaniappan, Rajkumar; Sundaraj, Kenneth; Sundaraj, Sebastian; Huliraj, N; Revadi, S S

2017-06-08

Auscultation is a medical procedure used for the initial diagnosis and assessment of lung and heart diseases. From this perspective, we propose assessing the performance of the extreme learning machine (ELM) classifiers for the diagnosis of pulmonary pathology using breath sounds. Energy and entropy features were extracted from the breath sound using the wavelet packet transform. The statistical significance of the extracted features was evaluated by one-way analysis of variance (ANOVA). The extracted features were inputted into the ELM classifier. The maximum classification accuracies obtained for the conventional validation (CV) of the energy and entropy features were 97.36% and 98.37%, respectively, whereas the accuracies obtained for the cross validation (CRV) of the energy and entropy features were 96.80% and 97.91%, respectively. In addition, maximum classification accuracies of 98.25% and 99.25% were obtained for the CV and CRV of the ensemble features, respectively. The results indicate that the classification accuracy obtained with the ensemble features was higher than those obtained with the energy and entropy features.

Scaffolding software: How does it influence student conceptual understanding and motivation?

NASA Astrophysics Data System (ADS)

Butler, Kyle A.

The purpose of this study was to determine the influence of scaffolding software on student conceptual understanding and motivation. This study also provides insight on how students use the scaffolding features found in Artemis and the extent to which features show a relationship to student conceptual understanding and motivation. A Randomized Solomon Four Group Design was used in this study. As students worked through a project based unit over photosynthesis, the students performed information seeking activities that were based on their own inquiry. For this purpose, the students in the experimental group used an example of scaffolding software called Artemis, while the students in the control group used a search engine of their choice. To measure conceptual understanding, the researcher analyzed student generated concept maps on photosynthesis using three different methods (quantitative, qualitative, hierarchical). To measure motivation, the researcher used a survey that measured motivation on five different indicators: intrinsic goal orientation, extrinsic goal orientation, task value, control of learning beliefs, self-efficacy for learning and performance. Finally, the researcher looked at the relationship and influence of the scaffolding features on two student performance scores at the end of the unit. This created a total of ten dependent variables in relationship to the treatment. Overall, the students used the collaborative features 25% of the time, the maintenance features 0.84% of the time, the organizational features 16% of the time, the saving/viewing features 7% of the time and the searching features 51% of the time. There were significant correlations between the saving/viewing features hits and the students' task value (r = .499, p < .05), the searching features hits and the students' self-efficacy for learning and performance (r = .553, p < .01), the collaborative features hits and the students' essay performance scores (r = .519, p < .05) and the maintenance features time and the qualitative analysis of the concept maps (r = .576, p < .01). Finally, the results indicated that the scaffolding features in Artemis did not influence student conceptual understanding and motivation.

Local multifractal detrended fluctuation analysis for non-stationary image's texture segmentation

NASA Astrophysics Data System (ADS)

Wang, Fang; Li, Zong-shou; Li, Jin-wei

2014-12-01

Feature extraction plays a great important role in image processing and pattern recognition. As a power tool, multifractal theory is recently employed for this job. However, traditional multifractal methods are proposed to analyze the objects with stationary measure and cannot for non-stationary measure. The works of this paper is twofold. First, the definition of stationary image and 2D image feature detection methods are proposed. Second, a novel feature extraction scheme for non-stationary image is proposed by local multifractal detrended fluctuation analysis (Local MF-DFA), which is based on 2D MF-DFA. A set of new multifractal descriptors, called local generalized Hurst exponent (Lhq) is defined to characterize the local scaling properties of textures. To test the proposed method, both the novel texture descriptor and other two multifractal indicators, namely, local Hölder coefficients based on capacity measure and multifractal dimension Dq based on multifractal differential box-counting (MDBC) method, are compared in segmentation experiments. The first experiment indicates that the segmentation results obtained by the proposed Lhq are better than the MDBC-based Dq slightly and superior to the local Hölder coefficients significantly. The results in the second experiment demonstrate that the Lhq can distinguish the texture images more effectively and provide more robust segmentations than the MDBC-based Dq significantly.

Beyond Correlation: Do Color Features Influence Attention in Rainforest?

PubMed Central

Frey, Hans-Peter; Wirz, Kerstin; Willenbockel, Verena; Betz, Torsten; Schreiber, Cornell; Troscianko, Tomasz; König, Peter

2011-01-01

Recent research indicates a direct relationship between low-level color features and visual attention under natural conditions. However, the design of these studies allows only correlational observations and no inference about mechanisms. Here we go a step further to examine the nature of the influence of color features on overt attention in an environment in which trichromatic color vision is advantageous. We recorded eye-movements of color-normal and deuteranope human participants freely viewing original and modified rainforest images. Eliminating red–green color information dramatically alters fixation behavior in color-normal participants. Changes in feature correlations and variability over subjects and conditions provide evidence for a causal effect of red–green color-contrast. The effects of blue–yellow contrast are much smaller. However, globally rotating hue in color space in these images reveals a mechanism analyzing color-contrast invariant of a specific axis in color space. Surprisingly, in deuteranope participants we find significantly elevated red–green contrast at fixation points, comparable to color-normal participants. Temporal analysis indicates that this is due to compensatory mechanisms acting on a slower time scale. Taken together, our results suggest that under natural conditions red–green color information contributes to overt attention at a low-level (bottom-up). Nevertheless, the results of the image modifications and deuteranope participants indicate that evaluation of color information is done in a hue-invariant fashion. PMID:21519395

Texture analysis on the fluence map to evaluate the degree of modulation for volumetric modulated arc therapy.

PubMed

Park, So-Yeon; Kim, Il Han; Ye, Sung-Joon; Carlson, Joel; Park, Jong Min

2014-11-01

Texture analysis on fluence maps was performed to evaluate the degree of modulation for volumetric modulated arc therapy (VMAT) plans. A total of six textural features including angular second moment, inverse difference moment, contrast, variance, correlation, and entropy were calculated for fluence maps generated from 20 prostate and 20 head and neck VMAT plans. For each of the textural features, particular displacement distances (d) of 1, 5, and 10 were adopted. To investigate the deliverability of each VMAT plan, gamma passing rates of pretreatment quality assurance, and differences in modulating parameters such as multileaf collimator (MLC) positions, gantry angles, and monitor units at each control point between VMAT plans and dynamic log files registered by the Linac control system during delivery were acquired. Furthermore, differences between the original VMAT plan and the plan reconstructed from the dynamic log files were also investigated. To test the performance of the textural features as indicators for the modulation degree of VMAT plans, Spearman's rank correlation coefficients (rs) with the plan deliverability were calculated. For comparison purposes, conventional modulation indices for VMAT including the modulation complexity score for VMAT, leaf travel modulation complexity score, and modulation index supporting station parameter optimized radiation therapy (MISPORT) were calculated, and their correlations were analyzed in the same way. There was no particular textural feature which always showed superior correlations with every type of plan deliverability. Considering the results comprehensively, contrast (d = 1) and variance (d = 1) generally showed considerable correlations with every type of plan deliverability. These textural features always showed higher correlations to the plan deliverability than did the conventional modulation indices, except in the case of modulating parameter differences. The rs values of contrast to the global gamma passing rates with criteria of 2%/2 mm, 2%/1 mm, and 1%/2 mm were 0.536, 0.473, and 0.718, respectively. The respective values for variance were 0.551, 0.481, and 0.688. In the case of local gamma passing rates, the rs values of contrast were 0.547, 0.578, and 0.620, respectively, and those of variance were 0.519, 0.527, and 0.569. All of the rs values in those cases were statistically significant (p < 0.003). In the cases of global and local gamma passing rates, MISPORT showed the highest correlations among the conventional modulation indices. For global passing rates, rs values of MISPORT were -0.420, -0.330, and -0.632, respectively, and those for local passing rates were -0.455, -0.490 and -0.502. The values of rs of contrast, variance, and MISPORT with the MLC errors were -0.863, -0.828, and 0.795, respectively, all with statistical significances (p < 0.001). The correlations with statistical significances between variance and dose-volumetric differences were observed more frequently than the others. The contrast (d = 1) and variance (d = 1) calculated from fluence maps of VMAT plans showed considerable correlations with the plan deliverability, indicating their potential use as indicators for assessing the degree of modulation of VMAT plans. Both contrast and variance consistently showed better performance than the conventional modulation indices for VMAT.

The Mariner 6 and 7 pictures of Mars

NASA Technical Reports Server (NTRS)

Collins, S. A., Jr.

1971-01-01

A comprehensive set of high quality reproductions of the final, computer-processed television pictures of Mars is presented. The genesis and unique characteristics of the pictures are explained, interesting features are pointed out, and some indication of their significance in the history of Mars investigations is provided.

Balmer and Metal Absorption Feature Gradients in M32

NASA Astrophysics Data System (ADS)

Worthey, Guy

2004-12-01

New data sources are used to assess Lick/IDS feature strength gradients inside the half-light radius Re of the compact Local Group elliptical galaxy M32. A Hubble Space Telescope (HST) STIS spectrum seemed to indicate ionized gas and a very young central stellar population. In fact, this conclusion is entirely spurious because of incomplete removal of ion hits. More robust ground-based spectra taken at the MDM Observatory are, in contrast, the most accurate measurements of Lick/IDS indices yet obtained for M32. All but a few (of 24 measured) indices show a statistically significant gradient. The CN indices show a maximum at 4" radius, dropping off both toward the nucleus and away from it. At 2" radius there is a discontinuity in the surface brightness profile, but this feature is not reflected in any spectral feature. Comparing with models, the index gradients indicate a mean age and abundance gradient in the sense that the nucleus is a factor of 2.5 younger and a factor of 0.3 dex more metal-rich than at 1Re. This conclusion is only weakly dependent on which index combinations are used and is robust to high accuracy. Stars near the M32 nucleus have a mean age and heavy element abundance [M/H] of (4.7 Gyr, +0.02), judging from models by Worthey with variable abundance ratios. This result has very small formal random errors, although, of course, there is significant age-metallicity degeneracy along an (age, abundance) line segment from (5.0 Gyr, 0.00) to (4.5 Gyr, +0.05). An abundance pattern of [C/M]=+0.077 (carbon abundance affects CN, C24668, and the bluer Balmer features), [N/M]=-0.13, [Mg/M]=-0.18, [Fe/M]~0.0, and [Na/M]=+0.12 is required to fit the feature data, with a fitting precision of about 0.01 dex (with two caveats: the [Fe/M] guess has about twice this precision because of the relative insensitivity of the Fe5335 feature to iron, and the [Na/M] value may be falsely amplified because of interstellar absorption). Model uncertainties make the accuracies of these values at least twice the magnitude of the precision. Forcing scaled-solar abundances does not change the age very much, but it increases the rms goodness of model-data fit by a factor of 3 and broadens the allowed range of age to +/-1 Gyr. The abundance ratios do not show strong trends with radius, except for the nuclear weakening of CN (measuring mainly N) mentioned above, which needs reconfirming with better data. The overall abundance pattern contrasts with larger elliptical galaxies, in which all measurable lighter elements are enhanced relative to iron and calcium. Nucleosynthetic theory does not provide a ready explanation for these mixtures.

Stratification of medulloblastoma on the basis of histopathological grading.

PubMed

Giangaspero, Felice; Wellek, Stefan; Masuoka, Jun; Gessi, Marco; Kleihues, Paul; Ohgaki, Hiroko

2006-07-01

Medulloblastoma (WHO grade IV) is an embryonal tumour of the cerebellum and the most common malignant central nervous system tumour in children. Despite significant advances in treatment, 5-year survival rates are still less than 70%, suggesting the presence of subgroups with different response to radio/chemotherapy. In the present study, we re-evaluated a series of 347 medulloblastomas from the SIOP II clinical trial of the International Society of Paediatric Oncology to identify features predictive of clinical outcome. Relapse free survival for medulloblastomas with severe anaplasia [5-year rate: S(60)=49.5%], was significantly shorter than for tumours with moderate or mild anaplasia S(60)=65.4%; P=0.001). The difference between both groups was even larger when the presence or absence of extensive apoptosis was included (46.5 vs. 66.7%; P=0.0216). Other histological features including nodularity, necrosis, vascular proliferation and the presence of beta-catenin mutations (7% of cases) were not predictive for relapse free survival. These findings indicate that degree of anaplasia is the most significant histologic feature predictive of the survival of medulloblastoma patients.

Object recognition of real targets using modelled SAR images

NASA Astrophysics Data System (ADS)

Zherdev, D. A.

2017-12-01

In this work the problem of recognition is studied using SAR images. The algorithm of recognition is based on the computation of conjugation indices with vectors of class. The support subspaces for each class are constructed by exception of the most and the less correlated vectors in a class. In the study we examine the ability of a significant feature vector size reduce that leads to recognition time decrease. The images of targets form the feature vectors that are transformed using pre-trained convolutional neural network (CNN).

Application of ERTS-1 imagery to the study of caribou movements and winter dispersal in relation to prevailing snowcover

NASA Technical Reports Server (NTRS)

Lent, P. C. (Principal Investigator)

1973-01-01

The author has identified the following significant results. Step-wise discriminate analysis has demonstrated the feasibility of feature identification using linear discriminate functions of ERTS-1 MSS band densities and their ratios. The analysis indicated that features such as small streams can be detected even when they are in dark mountain shadow. The potential utility of this and similar analytic techniques appears considerable, and the limits it can be applied to analysis of ERTS-1 imagery are not yet fully known.

Frontal-parietal synchrony in elderly EEG for visual search.

PubMed

Phillips, Steven; Takeda, Yuji

2010-01-01

Aging involves selective changes in attentional control. However, its precise effect on visual attention is difficult to discern from behavioural studies alone. In this paper, we employ a recently developed phase-locking measure of synchrony as an indicator of top-down/bottom-up control of attention to assess attentional control in the elderly. Fourteen participants (63-74 years) searched for a target item (coloured, oriented rectangular bar) among a display set of distractors. For the feature search condition, where none of the distractors shared a feature with the target, search time did not increase with display set size (two, or four items). For the conjunctive search condition, where each distractor shared either a colour or orientation feature with the target, search time increased with display size. Phase-locking analysis revealed a significant increase in high gamma-band (36-56 Hz) synchrony indicating greater bottom-up control for feature than conjunctive search. In view of our earlier study on younger (21-32 years) adults (Phillips and Takeda, 2009), these results suggest that older participants are more likely to use bottom-up control of attention, possibly triggered by their greater susceptibility to attentional capture, than younger participants. Copyright (c) 2009 Elsevier B.V. All rights reserved.

Variability of total ozone at Arosa, Switzerland, since 1931 related to atmospheric circulation indices

NASA Astrophysics Data System (ADS)

Brönnimann, S.; Luterbacher, J.; Schmutz, C.; Wanner, H.; Staehelin, J.

2000-08-01

Atmospheric circulation determines to a considerable extent the variability of lower stratospheric ozone and can modulate its long-term trends in Europe and the North Atlantic Region. Due to dynamical stratosphere-troposphere coupling, important features of the variability of the surface pressure field are reflected in the long-term total ozone record from Arosa, Switzerland. Significant (p<0.01) correlations between total ozone and different atmospheric circulation indices (NAOI, AOI, EU1, EU2) are found in all months except for April, June, July, and November for the period 1931 to 1997. An analysis of geopotential heights for the period 1958 to 1997 shows that these circulation anomaly patterns have upper tropospheric features over the North Atlantic-European sector that are consistent with a dynamical influence on total ozone.

40 CFR 258.15 - Unstable areas.

Code of Federal Regulations, 2014 CFR

2014-07-01

... determining whether an area is unstable: (1) On-site or local soil conditions that may result in significant... releases from a landfill. Unstable areas can include poor foundation conditions, areas susceptible to mass... conditions means those areas where features exist which indicate that a natural or man-induced event may...

40 CFR 258.15 - Unstable areas.

Code of Federal Regulations, 2013 CFR

2013-07-01

... determining whether an area is unstable: (1) On-site or local soil conditions that may result in significant... releases from a landfill. Unstable areas can include poor foundation conditions, areas susceptible to mass... conditions means those areas where features exist which indicate that a natural or man-induced event may...

40 CFR 258.15 - Unstable areas.

Code of Federal Regulations, 2012 CFR

2012-07-01

... determining whether an area is unstable: (1) On-site or local soil conditions that may result in significant... releases from a landfill. Unstable areas can include poor foundation conditions, areas susceptible to mass... conditions means those areas where features exist which indicate that a natural or man-induced event may...

Computation of reliable textural indices from multimodal brain MRI: suggestions based on a study of patients with diffuse intrinsic pontine glioma.

PubMed

Goya-Outi, Jessica; Orlhac, Fanny; Calmon, Raphael; Alentorn, Agusti; Nioche, Christophe; Philippe, Cathy; Puget, Stéphanie; Boddaert, Nathalie; Buvat, Irène; Grill, Jacques; Frouin, Vincent; Frouin, Frederique

2018-05-10

Few methodological studies regarding widely used textural indices robustness in MRI have been reported. In this context, this study aims to propose some rules to compute reliable textural indices from multimodal 3D brain MRI. Diagnosis and post-biopsy MR scans including T1, post-contrast T1, T2 and FLAIR images from thirty children with diffuse intrinsic pontine glioma (DIPG) were considered. The hybrid white stripe method was adapted to standardize MR intensities. Sixty textural indices were then computed for each modality in different regions of interest (ROI), including tumor and white matter (WM). Three types of intensity binning were compared [Formula: see text]: constant bin width and relative bounds; [Formula: see text] constant number of bins and relative bounds; [Formula: see text] constant number of bins and absolute bounds. The impact of the volume of the region was also tested within the WM. First, the mean Hellinger distance between patient-based intensity distributions decreased by a factor greater than 10 in WM and greater than 2.5 in gray matter after standardization. Regarding the binning strategy, the ranking of patients was highly correlated for 188/240 features when comparing [Formula: see text] with [Formula: see text], but for only 20 when comparing [Formula: see text] with [Formula: see text], and nine when comparing [Formula: see text] with [Formula: see text]. Furthermore, when using [Formula: see text] or [Formula: see text] texture indices reflected tumor heterogeneity as assessed visually by experts. Last, 41 features presented statistically significant differences between contralateral WM regions when ROI size slightly varies across patients, and none when using ROI of the same size. For regions with similar size, 224 features were significantly different between WM and tumor. Valuable information from texture indices can be biased by methodological choices. Recommendations are to standardize intensities in MR brain volumes, to use intensity binning with constant bin width, and to define regions with the same volumes to get reliable textural indices.

Before you see it, you see its parts: evidence for feature encoding and integration in preschool children and adults.

PubMed

Thompson, L A; Massaro, D W

1989-07-01

Preschool children and adults were compared in two experiments examining the basic issue of whether perceptual representations of objects are built-up from independent features along the dimensions of size and brightness. Experiment 1 was a visual search experiment. Subjects searched for targets which differed from distractors either by a single feature or by a conjunction of features. Results from preschoolers were comparable to those from adults, and were consistent with Treisman and Gelade's (1980, Cognitive Psychology, 12, 97-136) feature-integration theory of attention. Their theory states that independent features are encoded in parallel and are later combined with a spatial attention mechanism. However, children's significantly steeper conjunctive search slope indicated a slower speed of feature integration. In Experiment 2, four mathematical models of pattern recognition were tested against classification task data. The findings from both age groups were again consistent with a model assuming that size and brightness features are initially registered, and then integrated. Moreover, the data from Experiment 2 imply that perceptual growth entails small changes in the discriminability of featural representations; however, both experiments show that the operations performed on these representations are the same developmentally.

Characterizing trabecular bone structure for assessing vertebral fracture risk on volumetric quantitative computed tomography

NASA Astrophysics Data System (ADS)

Nagarajan, Mahesh B.; Checefsky, Walter A.; Abidin, Anas Z.; Tsai, Halley; Wang, Xixi; Hobbs, Susan K.; Bauer, Jan S.; Baum, Thomas; Wismüller, Axel

2015-03-01

While the proximal femur is preferred for measuring bone mineral density (BMD) in fracture risk estimation, the introduction of volumetric quantitative computed tomography has revealed stronger associations between BMD and spinal fracture status. In this study, we propose to capture properties of trabecular bone structure in spinal vertebrae with advanced second-order statistical features for purposes of fracture risk assessment. For this purpose, axial multi-detector CT (MDCT) images were acquired from 28 spinal vertebrae specimens using a whole-body 256-row CT scanner with a dedicated calibration phantom. A semi-automated method was used to annotate the trabecular compartment in the central vertebral slice with a circular region of interest (ROI) to exclude cortical bone; pixels within were converted to values indicative of BMD. Six second-order statistical features derived from gray-level co-occurrence matrices (GLCM) and the mean BMD within the ROI were then extracted and used in conjunction with a generalized radial basis functions (GRBF) neural network to predict the failure load of the specimens; true failure load was measured through biomechanical testing. Prediction performance was evaluated with a root-mean-square error (RMSE) metric. The best prediction performance was observed with GLCM feature `correlation' (RMSE = 1.02 ± 0.18), which significantly outperformed all other GLCM features (p < 0.01). GLCM feature correlation also significantly outperformed MDCTmeasured mean BMD (RMSE = 1.11 ± 0.17) (p< 10-4). These results suggest that biomechanical strength prediction in spinal vertebrae can be significantly improved through characterization of trabecular bone structure with GLCM-derived texture features.

Determining Image Processing Features Describing the Appearance of Challenging Mitotic Figures and Miscounted Nonmitotic Objects

PubMed Central

Gandomkar, Ziba; Brennan, Patrick C.; Mello-Thoms, Claudia

2017-01-01

Context: Previous studies showed that the agreement among pathologists in recognition of mitoses in breast slides is fairly modest. Aims: Determining the significantly different quantitative features among easily identifiable mitoses, challenging mitoses, and miscounted nonmitoses within breast slides and identifying which color spaces capture the difference among groups better than others. Materials and Methods: The dataset contained 453 mitoses and 265 miscounted objects in breast slides. The mitoses were grouped into three categories based on the confidence degree of three pathologists who annotated them. The mitoses annotated as “probably a mitosis” by the majority of pathologists were considered as the challenging category. The miscounted objects were recognized as a mitosis or probably a mitosis by only one of the pathologists. The mitoses were segmented using k-means clustering, followed by morphological operations. Morphological, intensity-based, and textural features were extracted from the segmented area and also the image patch of 63 × 63 pixels in different channels of eight color spaces. Holistic features describing the mitoses' surrounding cells of each image were also extracted. Statistical Analysis Used: The Kruskal–Wallis H-test followed by the Tukey-Kramer test was used to identify significantly different features. Results: The results indicated that challenging mitoses were smaller and rounder compared to other mitoses. Among different features, the Gabor textural features differed more than others between challenging mitoses and the easily identifiable ones. Sizes of the non-mitoses were similar to easily identifiable mitoses, but nonmitoses were rounder. The intensity-based features from chromatin channels were the most discriminative features between the easily identifiable mitoses and the miscounted objects. Conclusions: Quantitative features can be used to describe the characteristics of challenging mitoses and miscounted nonmitotic objects. PMID:28966834

Processing, Microstructures, and Properties of Nb-Based Metal/Silicide Alloys

DTIC Science & Technology

2003-07-01

Fig 15. (a) Fracture features at 800°C also indicated brittle failure, (b) indication of limited microplasticity in the Nbss phase...magnification, Fig. 15(b), there are some indication of microplasticity of the Nbss phase (arrows) but it was not sufficient to provide macroscopic...features at 800°C also indicated brittle failure, (b) indication of limited microplasticity in the Nbss phase (bright features) at

Eating disorder features and quality of life: Does gender matter?

PubMed

Wagner, Allison F; Stefano, Emily C; Cicero, David C; Latner, Janet D; Mond, Jonathan M

2016-10-01

This study examined whether gender moderates the associations between eating disorder features and quality-of-life impairment and whether eating disorder features can explain gender differences in quality of life in a sample of undergraduate students. The SF-12 Physical and Mental Component Summary Scales were used to measure health-related quality of life (HRQoL), and the Eating Disorders Examination Questionnaire (EDE-Q) was used to quantify eating disorder behaviors and cognitions. These self-report forms were completed by undergraduate men and women (n = 709). Gender was a significant predictor of mental HRQoL, such that women in this sample reported poorer mental HRQoL than men. Eating disorder cognitions were the strongest predictor of undergraduate students' mental and physical HRQoL, while binge eating negatively predicted their physical HRQoL only. Gender was not found to moderate the associations between eating disorder features and HRQoL, and eating disorder cognitions were found to mediate the association between gender and mental HRQoL such that a proportion of the difference between undergraduate men and women's mental HRQoL was attributable to eating disorder cognitions. This study provided further evidence of the significant impact of eating disorder features, particularly eating disorder cognitions, on HRQoL. The finding that gender did not moderate the relationships between eating disorder features and HRQoL indicates the importance of investigating these features in both men and women in future research.

Rigorous assessment and integration of the sequence and structure based features to predict hot spots

PubMed Central

2011-01-01

Background Systematic mutagenesis studies have shown that only a few interface residues termed hot spots contribute significantly to the binding free energy of protein-protein interactions. Therefore, hot spots prediction becomes increasingly important for well understanding the essence of proteins interactions and helping narrow down the search space for drug design. Currently many computational methods have been developed by proposing different features. However comparative assessment of these features and furthermore effective and accurate methods are still in pressing need. Results In this study, we first comprehensively collect the features to discriminate hot spots and non-hot spots and analyze their distributions. We find that hot spots have lower relASA and larger relative change in ASA, suggesting hot spots tend to be protected from bulk solvent. In addition, hot spots have more contacts including hydrogen bonds, salt bridges, and atomic contacts, which favor complexes formation. Interestingly, we find that conservation score and sequence entropy are not significantly different between hot spots and non-hot spots in Ab+ dataset (all complexes). While in Ab- dataset (antigen-antibody complexes are excluded), there are significant differences in two features between hot pots and non-hot spots. Secondly, we explore the predictive ability for each feature and the combinations of features by support vector machines (SVMs). The results indicate that sequence-based feature outperforms other combinations of features with reasonable accuracy, with a precision of 0.69, a recall of 0.68, an F1 score of 0.68, and an AUC of 0.68 on independent test set. Compared with other machine learning methods and two energy-based approaches, our approach achieves the best performance. Moreover, we demonstrate the applicability of our method to predict hot spots of two protein complexes. Conclusion Experimental results show that support vector machine classifiers are quite effective in predicting hot spots based on sequence features. Hot spots cannot be fully predicted through simple analysis based on physicochemical characteristics, but there is reason to believe that integration of features and machine learning methods can remarkably improve the predictive performance for hot spots. PMID:21798070

Exploring the optimal integration levels between SAR and optical data for better urban land cover mapping in the Pearl River Delta

NASA Astrophysics Data System (ADS)

Zhang, Hongsheng; Xu, Ru

2018-02-01

Integrating synthetic aperture radar (SAR) and optical data to improve urban land cover classification has been identified as a promising approach. However, which integration level is the most suitable remains unclear but important to many researchers and engineers. This study aimed to compare different integration levels for providing a scientific reference for a wide range of studies using optical and SAR data. SAR data from TerraSAR-X and ENVISAT ASAR in both WSM and IMP modes were used to be combined with optical data at pixel level, feature level and decision levels using four typical machine learning methods. The experimental results indicated that: 1) feature level that used both the original images and extracted features achieved a significant improvement of up to 10% compared to that using optical data alone; 2) different levels of fusion required different suitable methods depending on the data distribution and data resolution. For instance, support vector machine was the most stable at both the feature and decision levels, while random forest was suitable at the pixel level but not suitable at the decision level. 3) By examining the distribution of SAR features, some features (e.g., homogeneity) exhibited a close-to-normal distribution, explaining the improvement from the maximum likelihood method at the feature and decision levels. This indicated the benefits of using texture features from SAR data when being combined with optical data for land cover classification. Additionally, the research also shown that combining optical and SAR data does not guarantee improvement compared with using single data source for urban land cover classification, depending on the selection of appropriate fusion levels and fusion methods.

Asymmetric statistical features of the Chinese domestic and international gold price fluctuation

NASA Astrophysics Data System (ADS)

Cao, Guangxi; Zhao, Yingchao; Han, Yan

2015-05-01

Analyzing the statistical features of fluctuation is remarkably significant for financial risk identification and measurement. In this study, the asymmetric detrended fluctuation analysis (A-DFA) method was applied to evaluate asymmetric multifractal scaling behaviors in the Shanghai and New York gold markets. Our findings showed that the multifractal features of the Chinese and international gold spot markets were asymmetric. The gold return series persisted longer in an increasing trend than in a decreasing trend. Moreover, the asymmetric degree of multifractals in the Chinese and international gold markets decreased with the increase in fluctuation range. In addition, the empirical analysis using sliding window technology indicated that multifractal asymmetry in the Chinese and international gold markets was characterized by its time-varying feature. However, the Shanghai and international gold markets basically shared a similar asymmetric degree evolution pattern. The American subprime mortgage crisis (2008) and the European debt crisis (2010) enhanced the asymmetric degree of the multifractal features of the Chinese and international gold markets. Furthermore, we also make statistical tests for the results of multifractatity and asymmetry, and discuss the origin of them. Finally, results of the empirical analysis using the threshold autoregressive conditional heteroskedasticity (TARCH) and exponential generalized autoregressive conditional heteroskedasticity (EGARCH) models exhibited that good news had a more significant effect on the cyclical fluctuation of the gold market than bad news. Moreover, good news exerted a more significant effect on the Chinese gold market than on the international gold market.

Landscape scale controls on the vascular plant component of dissolved organic carbon across a freshwater delta

USGS Publications Warehouse

Eckard, Robert S.; Hernes, Peter J.; Bergamaschi, Brian A.; Stepanauskas, Ramunas; Kendall, Carol

2007-01-01

Lignin phenol concentrations and compositions were determined on dissolved organic carbon (DOC) extracts (XAD resins) within the Sacramento-San Joaquin River Delta (the Delta), the tidal freshwater portion of the San Francisco Bay Estuary, located in central California, USA. Fourteen stations were sampled, including the following habitats and land-use types: wetland, riverine, channelized waterway, open water, and island drains. Stations were sampled approximately seasonally from December, 1999 through May, 2001. DOC concentrations ranged from 1.3 mg L-1 within the Sacramento River to 39.9 mg L-1 at the outfall from an island drain (median 3.0 mg L-1), while lignin concentrations ranged from 3.0 μL-1 within the Sacramento River to 111 μL-1 at the outfall from an island drain (median 11.6 μL-1). Both DOC and lignin concentrations varied significantly among habitat/land-use types and among sampling stations. Carbon-normalized lignin yields ranged from 0.07 mg (100 mg OC)-1 at an island drain to 0.84 mg (100 mg OC)-1 for a wetland (median 0.36 mg (100 mg OC)-1), and also varied significantly among habitat/land-use types. A simple mass balance model indicated that the Delta acted as a source of lignin during late autumn through spring (10-83% increase) and a sink for lignin during summer and autumn (13-39% decrease). Endmember mixing models using S:V and C:V signatures of landscape scale features indicated strong temporal variation in sources of DOC export from the Delta, with riverine source signatures responsible for 50% of DOC in summer and winter, wetland signatures responsible for 40% of DOC in summer, winter, and late autumn, and island drains responsible for 40% of exported DOC in late autumn. A significant negative correlation was observed between carbon-normalized lignin yields and DOC bioavailability in two of the 14 sampling stations. This study is, to our knowledge, the first to describe organic vascular plant DOC sources at the level of localized landscape features, and is also the first to indicate a significant negative correlation between lignin and DOC bioavailability within environmental samples. Based upon observed trends: (1) Delta features exhibit significant spatial variability in organic chemical composition, and (2) localized Delta features appear to exert strong controls on terrigenous DOC as it passes through the Delta and is exported into the Pacific Ocean.

The role of psychological processes in estimates of stuttering severity.

PubMed

Manning, Walter; Gayle Beck, J

2013-12-01

To examine the associations of trait anxiety (STAI), social anxiety (SIAS), depression (BDI-II), and personality features (ADP-IV) with three measures of stuttering severity: %SS, Stuttering Severity, Instrument, and the Overall Assessment of the Speaker's Experience of Stuttering. Fifty adults with a history of stuttering served as participants. Participant scores on trait, anxiety, social anxiety, depression, and personality features were entered into a regression analysis, with the criterion variables (DVs) being: %SS, SSI-3, OASES total score. In order to explore the OASES, further, each of the four OASES subscales were also examined. A separate regression was conducted for, each dependent variable. The OASES total score model was significant (p<.0001) and revealed that social anxiety and, trait anxiety were the only significant predictors, with medium effect sizes noted for both variables. In contrast, percent syllables stuttered and the SSI were not significantly associated with psychological, variables, suggesting that anxiety may not always be related to overt indicators of stuttering. Depression and personality dysfunction were not significantly associated with any measure of, stuttering severity. Anxiety in the form of social and trait anxiety are significantly associated with stuttering, severity as indicated by the OASES. Traditional procedures for assigning severity ratings to individuals, who stutter based on percent syllables stuttered and the Stuttering Severity Instrument are not, significantly related to psychological processes central to the stuttering experience. Depression and, personality characteristics do not meaningfully account for stuttering. The reader will be able to: (a) differentiate forms of anxiety that are likely to be associated with stuttering (b) understand the importance of determining features of stuttering that go beyond the obvious, surface characteristics of stuttering frequency, and (c) discuss the important clinical and theoretical implications for understanding the degree of psychological dysfunction that is likely to be characteristic of those who stutter. Copyright © 2013 Elsevier Inc. All rights reserved.

Classifying the Indication for Colonoscopy Procedures: A Comparison of NLP Approaches in a Diverse National Healthcare System.

PubMed

Patterson, Olga V; Forbush, Tyler B; Saini, Sameer D; Moser, Stephanie E; DuVall, Scott L

2015-01-01

In order to measure the level of utilization of colonoscopy procedures, identifying the primary indication for the procedure is required. Colonoscopies may be utilized not only for screening, but also for diagnostic or therapeutic purposes. To determine whether a colonoscopy was performed for screening, we created a natural language processing system to identify colonoscopy reports in the electronic medical record system and extract indications for the procedure. A rule-based model and three machine-learning models were created using 2,000 manually annotated clinical notes of patients cared for in the Department of Veterans Affairs. Performance of the models was measured and compared. Analysis of the models on a test set of 1,000 documents indicates that the rule-based system performance stays fairly constant as evaluated on training and testing sets. However, the machine learning model without feature selection showed significant decrease in performance. Therefore, rule-based classification system appears to be more robust than a machine-learning system in cases when no feature selection is performed.

Cuticular features as indicators of environmental pollution

Treesearch

G. K. Sharma

1976-01-01

Several leaf cuticular features such as stomatal frequency, stomatal size, trichome length, type, and frequency, and subsidiary cell complex respond to environmental pollution in different ways and hence can be used as indicators of environmental pollution in an area. Several modifications in cuticular features under polluted environments seem to indicate ecotypic or...

Caudate nucleus reactivity predicts perceptual learning rate for visual feature conjunctions.

PubMed

Reavis, Eric A; Frank, Sebastian M; Tse, Peter U

2015-04-15

Useful information in the visual environment is often contained in specific conjunctions of visual features (e.g., color and shape). The ability to quickly and accurately process such conjunctions can be learned. However, the neural mechanisms responsible for such learning remain largely unknown. It has been suggested that some forms of visual learning might involve the dopaminergic neuromodulatory system (Roelfsema et al., 2010; Seitz and Watanabe, 2005), but this hypothesis has not yet been directly tested. Here we test the hypothesis that learning visual feature conjunctions involves the dopaminergic system, using functional neuroimaging, genetic assays, and behavioral testing techniques. We use a correlative approach to evaluate potential associations between individual differences in visual feature conjunction learning rate and individual differences in dopaminergic function as indexed by neuroimaging and genetic markers. We find a significant correlation between activity in the caudate nucleus (a component of the dopaminergic system connected to visual areas of the brain) and visual feature conjunction learning rate. Specifically, individuals who showed a larger difference in activity between positive and negative feedback on an unrelated cognitive task, indicative of a more reactive dopaminergic system, learned visual feature conjunctions more quickly than those who showed a smaller activity difference. This finding supports the hypothesis that the dopaminergic system is involved in visual learning, and suggests that visual feature conjunction learning could be closely related to associative learning. However, no significant, reliable correlations were found between feature conjunction learning and genotype or dopaminergic activity in any other regions of interest. Copyright © 2015 Elsevier Inc. All rights reserved.

Indications for axillary ultrasound use in breast cancer patients.

PubMed

Joh, Jennifer E; Han, Gang; Kiluk, John V; Laronga, Christine; Khakpour, Nazanin; Lee, M Catherine

2012-12-01

Axillary ultrasound has been adopted for preoperative planning in breast cancer. Our objective was to determine features predictive of abnormal AUS and/or positive axillary node needle biopsy (NBx). Single-institution database of breast cancer patients identified patients with preoperative AUS. Patient characteristics and outcomes were correlated with AUS and NBx. Significant features were identified using univariable and multivariable analysis and correlative statistics. Three hundred thirteen breast cancers were evaluated. Abnormal AUS was demonstrated in 250 cases (80%). Node needle biopsy was performed in 247 cases (79%). Sensitivity and specificity was 93% and 48% for AUS and 86% and 100% for NBx, respectively. Palpable axillary adenopathy was significant in logistic regression model (P < .05). There were positive correlations between tumor grade, clinical T and tumor-node-metastasis stage, invasive ductal carcinoma histology, and inflammatory breast carcinoma with AUS and NBx (P < .05). Clinicopathologic features (grade, histology, tumor size) might help guide judicious use of AUS. Copyright © 2012 Elsevier Inc. All rights reserved.

TU-F-CAMPUS-J-02: Evaluation of Textural Feature Extraction for Radiotherapy Response Assessment of Early Stage Breast Cancer Patients Using Diffusion Weighted MRI and Dynamic Contrast Enhanced MRI

DOE Office of Scientific and Technical Information (OSTI.GOV)

Xie, Y; Wang, C; Horton, J

Purpose: To investigate the feasibility of using classic textural feature extraction in radiotherapy response assessment, we studied a unique cohort of early stage breast cancer patients with paired pre - and post-radiation Diffusion Weighted MRI (DWI-MRI) and Dynamic Contrast Enhanced MRI (DCE-MRI). Methods: 15 female patients from our prospective phase I trial evaluating preoperative radiotherapy were included in this retrospective study. Each patient received a single-fraction radiation treatment, and DWI and DCE scans were conducted before and after the radiotherapy. DWI scans were acquired using a spin-echo EPI sequence with diffusion weighting factors of b = 0 and b =more » 500 mm{sup 2} /s, and the apparent diffusion coefficient (ADC) maps were calculated. DCE-MRI scans were acquired using a T{sub 1}-weighted 3D SPGR sequence with a temporal resolution of about 1 minute. The contrast agent (CA) was intravenously injected with a 0.1 mmol/kg bodyweight dose at 2 ml/s. Two parameters, volume transfer constant (K{sup trans} ) and k{sub ep} were analyzed using the two-compartment Tofts kinetic model. For DCE parametric maps and ADC maps, 33 textural features were generated from the clinical target volume (CTV) in a 3D fashion using the classic gray level co-occurrence matrix (GLCOM) and gray level run length matrix (GLRLM). Wilcoxon signed-rank test was used to determine the significance of each texture feature’s change after the radiotherapy. The significance was set to 0.05 with Bonferroni correction. Results: For ADC maps calculated from DWI-MRI, 24 out of 33 CTV features changed significantly after the radiotherapy. For DCE-MRI pharmacokinetic parameters, all 33 CTV features of K{sup trans} and 33 features of k{sub ep} changed significantly. Conclusion: Initial results indicate that those significantly changed classic texture features are sensitive to radiation-induced changes and can be used for assessment of radiotherapy response in breast cancer.« less

Hyperspectral Features of Oil-Polluted Sea Ice and the Response to the Contamination Area Fraction

PubMed Central

Li, Ying; Liu, Chengyu; Xie, Feng

2018-01-01

Researchers have studied oil spills in open waters using remote sensors, but few have focused on extracting reflectance features of oil pollution on sea ice. An experiment was conducted on natural sea ice in Bohai Bay, China, to obtain the spectral reflectance of oil-contaminated sea ice. The spectral absorption index (SAI), spectral peak height (SPH), and wavelet detail coefficient (DWT d5) were calculated using stepwise multiple linear regression. The reflectances of some false targets were measured and analysed. The simulated false targets were sediment, iron ore fines, coal dust, and the melt pool. The measured reflectances were resampled using five common sensors (GF-2, Landsat8-OLI, Sentinel3-OLCI, MODIS, and AVIRIS). Some significant spectral features could discriminate between oil-polluted and clean sea ice. The indices correlated well with the oil area fractions. All of the adjusted R2 values exceeded 0.9. The SPH model1, based on spectral features at 507–670 and 1627–1746 nm, displayed the best fitting. The resampled data indicated that these multi-spectral and hyper-spectral sensors could be used to detect crude oil on the sea ice if the effect of noise and spatial resolution are neglected. The spectral features and their identified changes may provide reference on sensor design and band selection. PMID:29342945

Differential Contributions of Polycystic Ovary Syndrome (PCOS) Manifestations to Psychological Symptoms.

PubMed

McCook, Judy G; Bailey, Beth A; Williams, Stacey L; Anand, Sheeba; Reame, Nancy E

2015-07-01

The purpose of this study was to investigate the relative contributions of previously identified Polycystic ovary syndrome (PCOS) manifestations (infertility, hirsutism, obesity, menstrual problems) to multiple psychological symptoms. Participants were 126 female endocrinology patient volunteers diagnosed with PCOS who completed a cross-sectional study of PCOS manifestations and psychological symptoms. Participants had significantly elevated scores on nine subscales of psychological symptoms. Menstrual problems were significantly associated with all symptom subscales as well as the global indicator, while hirsutism and obesity were significantly related to five or more subscales. After controlling for demographic factors, menstrual problems were the strongest predictor of psychological symptoms. Findings suggest features of excess body hair, obesity, and menstrual abnormalities carry unique risks for adverse psychologic symptoms, but menstrual problems may be the most salient of these features and deserve particular attention as a marker for psychological risk among women with PCOS.

Modeling Age-Friendly Environment, Active Aging, and Social Connectedness in an Emerging Asian Economy.

PubMed

Lai, Ming-Ming; Lein, Shi-Ying; Lau, Siok-Hwa; Lai, Ming-Ling

2016-01-01

This paper empirically tested eight key features of WHO guidelines to age-friendly community by surveying 211 informal caregivers and 402 self-care adults (aged 45 to 85 and above) in Malaysia. We examined the associations of these eight features with active aging and social connectedness through exploratory and confirmatory factor analyses. A structural model with satisfactory goodness-of-fit indices (CMIN/df = 1.11, RMSEA = 0.02, NFI = 0.97, TLI = 1.00, CFI = 1.00, and GFI = 0.96) indicates that transportation and housing, community support and health services, and outdoor spaces and buildings are statistically significant in creating an age-friendly environment. We found a statistically significant positive relationship between an age-friendly environment and active aging. This relationship is mediated by social connectedness. The results indicate that built environments such as accessible public transportations and housing, affordable and accessible healthcare services, and elderly friendly outdoor spaces and buildings have to be put into place before social environment in building an age-friendly environment. Otherwise, the structural barriers would hinder social interactions for the aged. The removal of the environmental barriers and improved public transportation services provide short-term solutions to meet the varied and growing needs of the older population.

Modeling Age-Friendly Environment, Active Aging, and Social Connectedness in an Emerging Asian Economy

PubMed Central

Lai, Ming-Ming; Lein, Shi-Ying; Lau, Siok-Hwa; Lai, Ming-Ling

2016-01-01

This paper empirically tested eight key features of WHO guidelines to age-friendly community by surveying 211 informal caregivers and 402 self-care adults (aged 45 to 85 and above) in Malaysia. We examined the associations of these eight features with active aging and social connectedness through exploratory and confirmatory factor analyses. A structural model with satisfactory goodness-of-fit indices (CMIN/df = 1.11, RMSEA = 0.02, NFI = 0.97, TLI = 1.00, CFI = 1.00, and GFI = 0.96) indicates that transportation and housing, community support and health services, and outdoor spaces and buildings are statistically significant in creating an age-friendly environment. We found a statistically significant positive relationship between an age-friendly environment and active aging. This relationship is mediated by social connectedness. The results indicate that built environments such as accessible public transportations and housing, affordable and accessible healthcare services, and elderly friendly outdoor spaces and buildings have to be put into place before social environment in building an age-friendly environment. Otherwise, the structural barriers would hinder social interactions for the aged. The removal of the environmental barriers and improved public transportation services provide short-term solutions to meet the varied and growing needs of the older population. PMID:27293889

Texture analysis on the fluence map to evaluate the degree of modulation for volumetric modulated arc therapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Park, So-Yeon; Institute of Radiation Medicine, Seoul National University Medical Research Center, Seoul 110-744; Biomedical Research Institute, Seoul National University College of Medicine, Seoul 110-744

Purpose: Texture analysis on fluence maps was performed to evaluate the degree of modulation for volumetric modulated arc therapy (VMAT) plans. Methods: A total of six textural features including angular second moment, inverse difference moment, contrast, variance, correlation, and entropy were calculated for fluence maps generated from 20 prostate and 20 head and neck VMAT plans. For each of the textural features, particular displacement distances (d) of 1, 5, and 10 were adopted. To investigate the deliverability of each VMAT plan, gamma passing rates of pretreatment quality assurance, and differences in modulating parameters such as multileaf collimator (MLC) positions, gantrymore » angles, and monitor units at each control point between VMAT plans and dynamic log files registered by the Linac control system during delivery were acquired. Furthermore, differences between the original VMAT plan and the plan reconstructed from the dynamic log files were also investigated. To test the performance of the textural features as indicators for the modulation degree of VMAT plans, Spearman’s rank correlation coefficients (r{sub s}) with the plan deliverability were calculated. For comparison purposes, conventional modulation indices for VMAT including the modulation complexity score for VMAT, leaf travel modulation complexity score, and modulation index supporting station parameter optimized radiation therapy (MI{sub SPORT}) were calculated, and their correlations were analyzed in the same way. Results: There was no particular textural feature which always showed superior correlations with every type of plan deliverability. Considering the results comprehensively, contrast (d = 1) and variance (d = 1) generally showed considerable correlations with every type of plan deliverability. These textural features always showed higher correlations to the plan deliverability than did the conventional modulation indices, except in the case of modulating parameter differences. The r{sub s} values of contrast to the global gamma passing rates with criteria of 2%/2 mm, 2%/1 mm, and 1%/2 mm were 0.536, 0.473, and 0.718, respectively. The respective values for variance were 0.551, 0.481, and 0.688. In the case of local gamma passing rates, the r{sub s} values of contrast were 0.547, 0.578, and 0.620, respectively, and those of variance were 0.519, 0.527, and 0.569. All of the r{sub s} values in those cases were statistically significant (p < 0.003). In the cases of global and local gamma passing rates, MI{sub SPORT} showed the highest correlations among the conventional modulation indices. For global passing rates, r{sub s} values of MI{sub SPORT} were −0.420, −0.330, and −0.632, respectively, and those for local passing rates were −0.455, −0.490 and −0.502. The values of r{sub s} of contrast, variance, and MI{sub SPORT} with the MLC errors were −0.863, −0.828, and 0.795, respectively, all with statistical significances (p < 0.001). The correlations with statistical significances between variance and dose-volumetric differences were observed more frequently than the others. Conclusions: The contrast (d = 1) and variance (d = 1) calculated from fluence maps of VMAT plans showed considerable correlations with the plan deliverability, indicating their potential use as indicators for assessing the degree of modulation of VMAT plans. Both contrast and variance consistently showed better performance than the conventional modulation indices for VMAT.« less

Substantial soil organic carbon retention along floodplains of mountain streams

NASA Astrophysics Data System (ADS)

Sutfin, Nicholas A.; Wohl, Ellen

2017-07-01

Small, snowmelt-dominated mountain streams have the potential to store substantial organic carbon in floodplain sediment because of high inputs of particulate organic matter, relatively lower temperatures compared with lowland regions, and potential for increased moisture conditions. This work (i) quantifies mean soil organic carbon (OC) content along 24 study reaches in the Colorado Rocky Mountains using 660 soil samples, (ii) identifies potential controls of OC content based on soil properties and spatial position with respect to the channel, and (iii) and examines soil properties and OC across various floodplain geomorphic features in the study area. Stepwise multiple linear regression (adjusted r2 = 0.48, p < 0.001) indicates that percentage of silt and clay, sample depth, percent sand, distance from the channel, and relative elevation from the channel are significant predictors of OC content in the study area. Principle component analysis indicates limited separation between geomorphic floodplain features based on predictors of OC content. A lack of significant differences among floodplain features suggests that the systematic random sampling employed in this study can capture the variability of OC across floodplains in the study area. Mean floodplain OC (6.3 ± 0.3%) is more variable but on average greater than values in uplands (1.5 ± 0.08% to 2.2 ± 0.14%) of the Colorado Front Range and higher than published values from floodplains in other regions, particularly those of larger rivers.

Interactive object recognition assistance: an approach to recognition starting from target objects

NASA Astrophysics Data System (ADS)

Geisler, Juergen; Littfass, Michael

1999-07-01

Recognition of target objects in remotely sensed imagery required detailed knowledge about the target object domain as well as about mapping properties of the sensing system. The art of object recognition is to combine both worlds appropriately and to provide models of target appearance with respect to sensor characteristics. Common approaches to support interactive object recognition are either driven from the sensor point of view and address the problem of displaying images in a manner adequate to the sensing system. Or they focus on target objects and provide exhaustive encyclopedic information about this domain. Our paper discusses an approach to assist interactive object recognition based on knowledge about target objects and taking into account the significance of object features with respect to characteristics of the sensed imagery, e.g. spatial and spectral resolution. An `interactive recognition assistant' takes the image analyst through the interpretation process by indicating step-by-step the respectively most significant features of objects in an actual set of candidates. The significance of object features is expressed by pregenerated trees of significance, and by the dynamic computation of decision relevance for every feature at each step of the recognition process. In the context of this approach we discuss the question of modeling and storing the multisensorial/multispectral appearances of target objects and object classes as well as the problem of an adequate dynamic human-machine-interface that takes into account various mental models of human image interpretation.

Survey on the novel hybrid aquatic-aerial amphibious aircraft: Aquatic unmanned aerial vehicle (AquaUAV)

NASA Astrophysics Data System (ADS)

Yang, Xingbang; Wang, Tianmiao; Liang, Jianhong; Yao, Guocai; Liu, Miao

2015-04-01

The aquatic unmanned aerial vehicle (AquaUAV), a kind of vehicle that can operate both in the air and the water, has been regarded as a new breakthrough to broaden the application scenario of UAV. Wide application prospects in military and civil field are more than bright, therefore many institutions have focused on the development of such a vehicle. However, due to the significant difference of the physical properties between the air and the water, it is rather difficult to design a fully-featured AquaUAV. Until now, majority of partially-featured AquaUAVs have been developed and used to verify the feasibility of an aquatic-aerial vehicle. In the present work, we classify the current partially-featured AquaUAV into three categories from the scope of the whole UAV field, i.e., the seaplane UAV, the submarine-launched UAV, and the submersible UAV. Then the recent advancements and common characteristics of the three kinds of AquaUAVs are reviewed in detail respectively. Then the applications of bionics in the design of AquaUAV, the transition mode between the air and the water, the morphing wing structure for air-water adaptation, and the power source and the propulsion type are summarized and discussed. The tradeoff analyses for different transition methods between the air and the water are presented. Furthermore, it indicates that applying the bionics into the design and development of the AquaUAV will be essential and significant. Finally, the significant technical challenges for the AquaUAV to change from a conception to a practical prototype are indicated.

The Influence of Changes in Size and Proportion of Selected Facial Features (Eyes, Nose, Mouth) on Assessment of Similarity between Female Faces.

PubMed

Lewandowski, Zdzisław

2015-09-01

The project aimed at finding the answers to the following two questions: to what extent does a change in size, height or width of the selected facial features influence the assessment of likeness between an original female composite portrait and a modified one? And how does the sex of the person who judges the images have an impact on the perception of likeness of facial features? The first stage of the project consisted of creating the image of the averaged female faces. Then the basic facial features like eyes, nose and mouth were cut out of the averaged face and each of these features was transformed in three ways: its size was changed by reduction or enlargement, its height was modified through reduction or enlargement of the above-mentioned features and its width was altered through widening or narrowing. In each out of six feature alternation methods, intensity of modification reached up to 20% of the original size with changes every 2%. The features altered in such a way were again stuck onto the original faces and retouched. The third stage consisted of the assessment, performed by the judges of both sexes, of the extent of likeness between the averaged composite portrait (without any changes) and the modified portraits. The results indicate that there are significant differences in the assessment of likeness of the portraits with some features modified to the original ones. The images with changes in the size and height of the nose received the lowest scores on the likeness scale, which indicates that these changes were perceived by the subjects as the most important. The photos with changes in the height of lip vermillion thickness (the lip height), lip width and the height and width of eye slit, in turn, received high scores of likeness, in spite of big changes, which signifies that these modifications were perceived as less important when compared to the other features investigated.

Defect detection of helical gears based on time-frequency analysis and using multi-layer fusion network

NASA Astrophysics Data System (ADS)

Ebrahimi Orimi, H.; Esmaeili, M.; Refahi Oskouei, A.; Mirhadizadehd, S. A.; Tse, P. W.

2017-10-01

Condition monitoring of rotary devices such as helical gears is an issue of great significance in industrial projects. This paper introduces a feature extraction method for gear fault diagnosis using wavelet packet due to its higher frequency resolution. During this investigation, the mother wavelet Daubechies 10 (Db-10) was applied to calculate the coefficient entropy of each frequency band of 5th level (32 frequency bands) as features. In this study, the peak value of the signal entropies was selected as applicable features in order to improve frequency band differentiation and reduce feature vectors' dimension. Feature extraction is followed by the fusion network where four different structured multi-layer perceptron networks are trained to classify the recorded signals (healthy/faulty). The robustness of fusion network outputs is greater compared to perceptron networks. The results provided by the fusion network indicate a classification of 98.88 and 97.95% for healthy and faulty classes, respectively.

Archaeological investigations at a toolstone source area and temporary camp: Sample Unit 19-25, Nevada Test Site, Nye County, Nevada. Technical report No. 77

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jones, R.C.; DuBarton, A.; Edwards, S.

1993-12-31

Archaeological investigations were initiated at Sample Unit 19--25 to retrieve information concerning settlement and subsistence data on the aboriginal hunter and gatherers in the area. Studies included collection and mapping of 35.4 acres at site 26NY1408 and excavation and mapping of 0.02 acres at site 26NY7847. Cultural resources include two rock and brush structures and associated caches and a large lithic toolstone source area and lithic artifact scatter. Temporally diagnostic artifacts indicate periodic use throughout the last 12,000 years; however dates associated with projectile points indicate most use was in the Middle and Late Archaic. Radiocarbon dates from the rockmore » and brush structures at site 26NY7847 indicate a construction date of A.D. 1640 and repair between A.D. 1800 and 1950 for feature 1 and between A.D. 1330 and 1390 and repair at A.D. 1410 for feature 2. The dates associated with feature 2 place its construction significantly earlier than similar structures found elsewhere on Pahute Mesa. Activity areas appear to reflect temporary use of the area for procurement of available lithic and faunal resources and the manufacture of tools.« less

A comparison study of image features between FFDM and film mammogram images

PubMed Central

Jing, Hao; Yang, Yongyi; Wernick, Miles N.; Yarusso, Laura M.; Nishikawa, Robert M.

2012-01-01

Purpose: This work is to provide a direct, quantitative comparison of image features measured by film and full-field digital mammography (FFDM). The purpose is to investigate whether there is any systematic difference between film and FFDM in terms of quantitative image features and their influence on the performance of a computer-aided diagnosis (CAD) system. Methods: The authors make use of a set of matched film-FFDM image pairs acquired from cadaver breast specimens with simulated microcalcifications consisting of bone and teeth fragments using both a GE digital mammography system and a screen-film system. To quantify the image features, the authors consider a set of 12 textural features of lesion regions and six image features of individual microcalcifications (MCs). The authors first conduct a direct comparison on these quantitative features extracted from film and FFDM images. The authors then study the performance of a CAD classifier for discriminating between MCs and false positives (FPs) when the classifier is trained on images of different types (film, FFDM, or both). Results: For all the features considered, the quantitative results show a high degree of correlation between features extracted from film and FFDM, with the correlation coefficients ranging from 0.7326 to 0.9602 for the different features. Based on a Fisher sign rank test, there was no significant difference observed between the features extracted from film and those from FFDM. For both MC detection and discrimination of FPs from MCs, FFDM had a slight but statistically significant advantage in performance; however, when the classifiers were trained on different types of images (acquired with FFDM or SFM) for discriminating MCs from FPs, there was little difference. Conclusions: The results indicate good agreement between film and FFDM in quantitative image features. While FFDM images provide better detection performance in MCs, FFDM and film images may be interchangeable for the purposes of training CAD algorithms, and a single CAD algorithm may be applied to either type of images. PMID:22830771

Diagnostic standards for dopaminergic augmentation of restless legs syndrome: report from a World Association of Sleep Medicine-International Restless Legs Syndrome Study Group consensus conference at the Max Planck Institute.

PubMed

García-Borreguero, Diego; Allen, Richard P; Kohnen, Ralf; Högl, Birgit; Trenkwalder, Claudia; Oertel, Wolfgang; Hening, Wayne A; Paulus, Walter; Rye, David; Walters, Arthur; Winkelmann, Juliane; Earley, Christopher J

2007-08-01

Augmentation of symptom severity is the main complication of dopaminergic treatment of restless legs syndrome (RLS). The current article reports on the considerations of augmentation that were made during a European Restless Legs Syndrome Study Group (EURLSSG)-sponsored Consensus Conference in April 2006 at the Max Planck Institute (MPI) in Munich, Germany, the conclusions of which were endorsed by the International RLS Study Group (IRLSSG) and the World Association of Sleep Medicine (WASM). The Consensus Conference sought to develop a better understanding of augmentation and generate a better operational definition for its clinical identification. Current concepts of the pathophysiology, clinical features, and therapy of RLS augmentation were evaluated by subgroups who presented a summary of their findings for general consideration and discussion. Recent data indicating sensitivity and specificity of augmentation features for identification of augmentation were also evaluated. The diagnostic criteria of augmentation developed at the National Institutes of Health (NIH) conference in 2002 were reviewed in light of current data and theoretical understanding of augmentation. The diagnostic value and criteria for each of the accepted features of augmentation were considered by the group. A consensus was then developed for a revised statement of the diagnostic criteria for augmentation. Five major diagnostic features of augmentation were identified: usual time of RLS symptom onset each day, number of body parts with RLS symptoms, latency to symptoms at rest, severity of the symptoms when they occur, and effects of dopaminergic medication on symptoms. The quantitative data available relating the time of RLS onset and the presence of other features indicated optimal augmentation criteria of either a 4-h advance in usual starting time for RLS symptoms or a combination of the occurrence of other features. A paradoxical response to changes in medication dose also indicates augmentation. Clinical significance of augmentation is defined. The Consensus Conference agreed upon new operational criteria for the clinical diagnosis of RLS augmentation: the MPI diagnostic criteria for augmentation. Areas needing further consideration for validating these criteria and for understanding the underlying biology of RLS augmentation are indicated.

Humidity-dependent bacterial cells functional morphometry investigations using atomic force microscope.

PubMed

Nikiyan, Hike; Vasilchenko, Alexey; Deryabin, Dmitry

2010-01-01

The effect of a relative humidity (RH) in a range of 93-65% on morphological and elastic properties of Bacillus cereus and Escherichia coli cells was evaluated using atomic force microscopy. It is shown that gradual dehumidification of bacteria environment has no significant effect on cell dimensional features and considerably decreases them only at 65% RH. The increasing of the bacteria cell wall roughness and elasticity occurs at the same time. Observed changes indicate that morphological properties of B. cereus are rather stable in wide range of relative humidity, whereas E. coli are more sensitive to drying, significantly increasing roughness and stiffness parameters at RH

Syntheses and characterization of liposome-incorporated adamantyl aminoguanidines.

PubMed

Šekutor, Marina; Štimac, Adela; Mlinarić-Majerski, Kata; Frkanec, Ruža

2014-08-21

A series of mono and bis-aminoguanidinium adamantane derivatives has been synthesized and incorporated into liposomes. They combine two biomedically significant molecules, the adamantane moiety and the guanidinium group. The adamantane moiety possesses the membrane compatible features while the cationic guanidinium subunit was recognized as a favourable structural feature for binding to complementary molecules comprising phosphate groups. The liposome formulations of adamantyl aminoguanidines were characterized and it was shown that the entrapment efficiency of the examined compounds is significant. In addition, it was demonstrated that liposomes with incorporated adamantyl aminoguanidines effectively recognized the complementary liposomes via the phosphate group. These results indicate that adamantane derivatives bearing guanidinium groups might be versatile tools for biomedical application, from studies of molecular recognition processes to usage in drug formulation and cell targeting.

Temporal analysis of intratumoral metabolic heterogeneity characterized by textural features in cervical cancer.

PubMed

Yang, Fei; Thomas, Maria A; Dehdashti, Farrokh; Grigsby, Perry W

2013-05-01

The aim of this pilot study was to explore heterogeneity in the temporal behavior of intratumoral [(18)F]fluorodeoxyglucose (FDG) accumulation at a regional scale in patients with cervical cancer undergoing chemoradiotherapy. Included in the study were 20 patients with FIGO stages IB1 to IVA cervical cancer treated with combined chemoradiotherapy. Patients underwent FDG PET/CT before treatment, during weeks 2 and 4 of treatment, and 12 weeks after completion of therapy. Patients were classified based on response to therapy as showing a complete metabolic response (CMR), a partial metabolic response (PMR), or residual disease and the development of new disease (NEW). Based on the presence of residual primary tumor following therapy, patients were divided into two groups, CMR and PMR/NEW. Temporal profiles of intratumoral FDG heterogeneity as characterized by textural features at a regional scale were assessed and compared with those of the standardized uptake value (SUV) indices (SUVmax and SUVmean) within the context of differentiating response groups. Textural features at a regional scale with emphasis on characterizing contiguous regions of high uptake in tumors decreased significantly with time (P < 0.001) in the CMR group, while features describing contiguous regions of low uptake along with those measuring the nonuniformity of contiguous isointense regions in tumors exhibited significant temporal changes in the PMR/NEW group (P < 0.03) but showed no persistent trends with time. Both SUV indices showed significant changes during the course of the disease in both patient groups (P < 0.001 for SUVmax and SUVmean in the CMR group; P = 0.0109 and 0.0136, respectively, for SUVmax and SUVmean in the PMR/NEW group), and also decreased at a constant rate in the CMR group and decreased up to the 4th week of treatment and then increased in the PMR/NEW group. The temporal changes in the heterogeneity of intratumoral FDG distribution characterized at a regional scale using image-based textural features may provide an adjunctive or alternative option for understanding tumor response to chemoradiotherapy and interpreting FDG accumulation dynamics in patients with malignant cervical tumors during the course of the disease.

Exploring the relationship between vegetation spectra and eco-geo-environmental conditions in karst region, Southwest China.

PubMed

Yue, Yuemin; Wang, Kelin; Zhang, Bing; Chen, Zhengchao; Jiao, Quanjun; Liu, Bo; Chen, Hongsong

2010-01-01

Remote sensing of local environmental conditions is not accessible if substrates are covered with vegetation. This study explored the relationship between vegetation spectra and karst eco-geo-environmental conditions. Hyperspectral remote sensing techniques showed that there were significant differences between spectral features of vegetation mainly distributed in karst and non-karst regions, and combination of 1,300- to 2,500-nm reflectance and 400- to 680-nm first-derivative spectra could delineate karst and non-karst vegetation groups. Canonical correspondence analysis (CCA) successfully assessed to what extent the variation of vegetation spectral features can be explained by associated eco-geo-environmental variables, and it was found that soil moisture and calcium carbonate contents had the most significant effects on vegetation spectral features in karst region. Our study indicates that vegetation spectra is tightly linked to eco-geo-environmental conditions and CCA is an effective means of studying the relationship between vegetation spectral features and eco-geo-environmental variables. Employing a combination of spectral and spatial analysis, it is anticipated that hyperspectral imagery can be used in interpreting or mapping eco-geo-environmental conditions covered with vegetation in karst region.

Heart Sound Biometric System Based on Marginal Spectrum Analysis

PubMed Central

Zhao, Zhidong; Shen, Qinqin; Ren, Fangqin

2013-01-01

This work presents a heart sound biometric system based on marginal spectrum analysis, which is a new feature extraction technique for identification purposes. This heart sound identification system is comprised of signal acquisition, pre-processing, feature extraction, training, and identification. Experiments on the selection of the optimal values for the system parameters are conducted. The results indicate that the new spectrum coefficients result in a significant increase in the recognition rate of 94.40% compared with that of the traditional Fourier spectrum (84.32%) based on a database of 280 heart sounds from 40 participants. PMID:23429515

The Effects of Legumes on Metabolic Features, Insulin Resistance and Hepatic Function Tests in Women with Central Obesity: A Randomized Controlled Trial

PubMed Central

Alizadeh, Mohammad; Gharaaghaji, Rasool; Gargari, Bahram Pourghassem

2014-01-01

Background: The effect of high-legume hypocaloric diet on metabolic features in women is unclear. This study provided an opportunity to find effects of high-legume diet on metabolic features in women who consumed high legumes at pre-study period. Methods: In this randomized controlled trial after 2 weeks of a run-in period on an isocaloric diet, 42 premenopausal women with central obesity were randomly assigned into two groups: (1) Hypocaloric diet enriched in legumes (HDEL) and (2) hypocaloric diet without legumes (HDWL) for 6 weeks. The following variables were assessed before intervention and 3 and 6 weeks after its beginning: Waist circumference (WC), systolic blood pressure (SBP), diastolic blood pressure (DBP), fasting serum concentrations of triglyceride (TG), high density lipoprotein cholesterol, fasting blood sugar (FBS), insulin, homeostasis model of insulin resistance (HOMA-IR), alanine aminotransferase (ALT) and aspartate aminotransferase (AST). We used multifactor model of nested multivariate analysis of variance repeated measurements and t-test for statistical analysis. Results: HDEL and HDWL significantly reduced the WC. HDEL significantly reduced the SBP and TG. Both HDEL and HDWL significantly increased fasting concentration of insulin and HOMA-IR after 3 weeks, but their significant effects on insulin disappeared after 6 weeks and HDEL returned HOMA-IR to basal levels in the subsequent 3 weeks. In HDEL group percent of decrease in AST and ALT between 3rd and 6th weeks was significant. In HDWL group percent of increase in SBP, DBP, FBS and TG between 3rd and 6th weeks was significant. Conclusions: The study indicated beneficial effects of hypocaloric legumes on metabolic features. PMID:25013690

Cue combination in a combined feature contrast detection and figure identification task.

PubMed

Meinhardt, Günter; Persike, Malte; Mesenholl, Björn; Hagemann, Cordula

2006-11-01

Target figures defined by feature contrast in spatial frequency, orientation or both cues had to be detected in Gabor random fields and their shape had to be identified in a dual task paradigm. Performance improved with increasing feature contrast and was strongly correlated among both tasks. Subjects performed significantly better with combined cues than with single cues. The improvement due to cue summation was stronger than predicted by the assumption of independent feature specific mechanisms, and increased with the performance level achieved with single cues until it was limited by ceiling effects. Further, cue summation was also strongly correlated among tasks: when there was benefit due to the additional cue in feature contrast detection, there was also benefit in figure identification. For the same performance level achieved with single cues, cue summation was generally larger in figure identification than in feature contrast detection, indicating more benefit when processes of shape and surface formation are involved. Our results suggest that cue combination improves spatial form completion and figure-ground segregation in noisy environments, and therefore leads to more stable object vision.

Comparative study of feature selection with ensemble learning using SOM variants

NASA Astrophysics Data System (ADS)

Filali, Ameni; Jlassi, Chiraz; Arous, Najet

2017-03-01

Ensemble learning has succeeded in the growth of stability and clustering accuracy, but their runtime prohibits them from scaling up to real-world applications. This study deals the problem of selecting a subset of the most pertinent features for every cluster from a dataset. The proposed method is another extension of the Random Forests approach using self-organizing maps (SOM) variants to unlabeled data that estimates the out-of-bag feature importance from a set of partitions. Every partition is created using a various bootstrap sample and a random subset of the features. Then, we show that the process internal estimates are used to measure variable pertinence in Random Forests are also applicable to feature selection in unsupervised learning. This approach aims to the dimensionality reduction, visualization and cluster characterization at the same time. Hence, we provide empirical results on nineteen benchmark data sets indicating that RFS can lead to significant improvement in terms of clustering accuracy, over several state-of-the-art unsupervised methods, with a very limited subset of features. The approach proves promise to treat with very broad domains.

Discriminative prediction of mammalian enhancers from DNA sequence

PubMed Central

Lee, Dongwon; Karchin, Rachel; Beer, Michael A.

2011-01-01

Accurately predicting regulatory sequences and enhancers in entire genomes is an important but difficult problem, especially in large vertebrate genomes. With the advent of ChIP-seq technology, experimental detection of genome-wide EP300/CREBBP bound regions provides a powerful platform to develop predictive tools for regulatory sequences and to study their sequence properties. Here, we develop a support vector machine (SVM) framework which can accurately identify EP300-bound enhancers using only genomic sequence and an unbiased set of general sequence features. Moreover, we find that the predictive sequence features identified by the SVM classifier reveal biologically relevant sequence elements enriched in the enhancers, but we also identify other features that are significantly depleted in enhancers. The predictive sequence features are evolutionarily conserved and spatially clustered, providing further support of their functional significance. Although our SVM is trained on experimental data, we also predict novel enhancers and show that these putative enhancers are significantly enriched in both ChIP-seq signal and DNase I hypersensitivity signal in the mouse brain and are located near relevant genes. Finally, we present results of comparisons between other EP300/CREBBP data sets using our SVM and uncover sequence elements enriched and/or depleted in the different classes of enhancers. Many of these sequence features play a role in specifying tissue-specific or developmental-stage-specific enhancer activity, but our results indicate that some features operate in a general or tissue-independent manner. In addition to providing a high confidence list of enhancer targets for subsequent experimental investigation, these results contribute to our understanding of the general sequence structure of vertebrate enhancers. PMID:21875935

Graphical augmentations to the funnel plot assess the impact of additional evidence on a meta-analysis.

PubMed

Langan, Dean; Higgins, Julian P T; Gregory, Walter; Sutton, Alexander J

2012-05-01

We aim to illustrate the potential impact of a new study on a meta-analysis, which gives an indication of the robustness of the meta-analysis. A number of augmentations are proposed to one of the most widely used of graphical displays, the funnel plot. Namely, 1) statistical significance contours, which define regions of the funnel plot in which a new study would have to be located to change the statistical significance of the meta-analysis; and 2) heterogeneity contours, which show how a new study would affect the extent of heterogeneity in a given meta-analysis. Several other features are also described, and the use of multiple features simultaneously is considered. The statistical significance contours suggest that one additional study, no matter how large, may have a very limited impact on the statistical significance of a meta-analysis. The heterogeneity contours illustrate that one outlying study can increase the level of heterogeneity dramatically. The additional features of the funnel plot have applications including 1) informing sample size calculations for the design of future studies eligible for inclusion in the meta-analysis; and 2) informing the updating prioritization of a portfolio of meta-analyses such as those prepared by the Cochrane Collaboration. Copyright © 2012 Elsevier Inc. All rights reserved.

Evaluating a bilingual voluntary community-based healthcare organization.

PubMed

Jason, Leonard A; Digangi, Julia A; Alvarez, Josefina; Contreras, Richard; Lopez-Tamayo, Roberto; Gallardo, Stephanie; Flores, Samantha

2013-01-01

The current study compared traditional recovery homes for individuals with substance use disorders with homes that had been modified to feature culturally congruent communication styles. Findings indicated significant increases in employment income, with the size of the change significantly greater in the culturally modified houses. Significant decreases in alcohol use over time were also found, with larger decreases over time in the traditional recovery homes. Use of prescribed medications and days using drugs significantly decreased over time, but not differentially for those in the two types of recovery homes. The implications of these findings are discussed.

Community Perceptions of Specific Skin Features of Possible Melanoma

ERIC Educational Resources Information Center

Baade, Peter D.; Balanda, Kevin P.; Stanton, Warren R.; Lowe, John B.; Del Mar, Chris B.

2004-01-01

Background: Melanoma can be curable if detected early. One component of detecting melanoma is an awareness of the important features of the disease. It is currently not clear which features the community view as indicative of melanoma. Objective: To investigate which features of the skin members of an urban community believe may indicate skin…

Selected PET radiomic features remain the same.

PubMed

Tsujikawa, Tetsuya; Tsuyoshi, Hideaki; Kanno, Masafumi; Yamada, Shizuka; Kobayashi, Masato; Narita, Norihiko; Kimura, Hirohiko; Fujieda, Shigeharu; Yoshida, Yoshio; Okazawa, Hidehiko

2018-04-17

We investigated whether PET radiomic features are affected by differences in the scanner, scan protocol, and lesion location using 18 F-FDG PET/CT and PET/MR scans. SUV, TMR, skewness, kurtosis, entropy, and homogeneity strongly correlated between PET/CT and PET/MR images. SUVs were significantly higher on PET/MR 0-2 min and PET/MR 0-10 min than on PET/CT in gynecological cancer ( p = 0.008 and 0.008, respectively), whereas no significant difference was observed between PET/CT, PET/MR 0-2 min , and PET/MR 0-10 min images in oral cavity/oropharyngeal cancer. TMRs on PET/CT, PET/MR 0-2 min , and PET/MR 0-10 min increased in this order in gynecological cancer and oral cavity/oropharyngeal cancer. In contrast to conventional and histogram indices, 4 textural features (entropy, homogeneity, SRE, and LRE) were not significantly different between PET/CT, PET/MR 0-2 min , and PET/MR 0-10 min images. 18 F-FDG PET radiomic features strongly correlated between PET/CT and PET/MR images. Dixon-based attenuation correction on PET/MR images underestimated tumor tracer uptake more significantly in oral cavity/oropharyngeal cancer than in gynecological cancer. 18 F-FDG PET textural features were affected less by differences in the scanner and scan protocol than conventional and histogram features, possibly due to the resampling process using a medium bin width. Eight patients with gynecological cancer and 7 with oral cavity/oropharyngeal cancer underwent a whole-body 18 F-FDG PET/CT scan and regional PET/MR scan in one day. PET/MR scans were performed for 10 minutes in the list mode, and PET/CT and 0-2 min and 0-10 min PET/MR images were reconstructed. The standardized uptake value (SUV), tumor-to-muscle SUV ratio (TMR), skewness, kurtosis, entropy, homogeneity, short-run emphasis (SRE), and long-run emphasis (LRE) were compared between PET/CT, PET/MR 0-2 min , and PET/MR 0-10 min images.

Aeolian Rat Tails (ARTs): A New Morphological Indicator of Abrasion Direction

NASA Astrophysics Data System (ADS)

Favaro, E. A.; Hugenholtz, C.; Barchyn, T.

2016-12-01

Aeolian rat tails (ARTs) are a previously undocumented aeolian abrasion feature observed on ignimbrite surfaces in the Puna Plateau of Northwest Argentina and bare morphological similarity to small-scale features on Mars. We describe the terrestrial features and present an evolutionary sequence from inception to demise. ARTs are regionally-ubiquitous and characterized by a windward abrasion-resistant lithic clast and a downwind-tapering tail. The size of ARTs is controlled by the diameter of the windward lithic clast, observed on the sub-decimeter to meter scale. Their distribution throughout the Campo de Piedra Pómez, and adjacent regions is determined by the ignimbrite clast content. ARTs develop under a uni-modal abrasion direction when lithic clasts are eroded out of the ignimbrite matrix, protrude from the surface, and shelter material directly behind the clast. As the surrounding material is eroded away, a downwind-tapered tail develops. Continued erosion of the adjacent surface leads to the undercutting of clasts, liberating them from the feature where, if small enough, the clasts can be transported downwind, leading to the destruction of the tail and ultimately the feature. This evolutionary sequence accounts not only for the morphology of the feature, but also the presence of loose clasts on the ignimbrite surface, which plays a role in the development of other enigmatic landforms in the area, such as periodic bedrock ridges, yardangs, and megaripples. The significance of the identification of ARTs is due to the necessity of uni-modal abrasion direction for their development, thereby making their orientation a diagnostic indicator of long-term aeolian abrasion direction. ARTs are likely analogs of features identified by MSL Curiosity Rover on Mars, possibly providing information on past and present wind regimes.

Pollenkitt wetting mechanism enables species-specific tunable pollen adhesion.

PubMed

Lin, Haisheng; Gomez, Ismael; Meredith, J Carson

2013-03-05

Plant pollens are microscopic particles exhibiting a remarkable breadth of complex solid surface features. In addition, many pollen grains are coated with a viscous liquid, "pollenkitt", thought to play important roles in pollen dispersion and adhesion. However, there exist no quantitative studies of the effects of solid surface features or pollenkitt on adhesion of pollen grains, and it remains unclear what role these features play in pollen adhesion and transport. We report AFM adhesion measurements of five pollen species with a series of test surfaces in which each pollen has a unique solid surface morphology and pollenkitt volume. The results indicate that the combination of surface morphology (size and shape of echinate or reticulate features) with the pollenkitt volume provides pollens with a remarkably tunable adhesion to surfaces. With pollenkitt removed, pollen grains had relatively low adhesion strengths that were independent of surface chemistry and scalable with the tip radius of the pollen's ornamentation features, according to the Hamaker model. With the pollenkitt intact, adhesion was up to 3-6 times higher than the dry grains and exhibited strong substrate dependence. The adhesion enhancing effect of pollenkitt was driven by the formation of pollenkitt capillary bridges and was surprisingly species-dependent, with echinate insect-pollinated species (dandelion and sunflower) showing significantly stronger adhesion and higher substrate dependence than wind-pollinated species (ragweed, poplar, and olive). The combination of high pollenkitt volume and large convex, spiny surface features in echinate entomophilous varieties appears to enhance the spreading area of the liquid pollenkitt relative to varieties of pollen with less pollenkitt volume and less pronounced surface features. Measurements of pollenkitt surface energy indicate that the adhesive strength of capillary bridges is primarily dependent on nonpolar van der Waals interactions, with some contribution from the Lewis basic component of surface energy.

Distinct roles of arginases 1 and 2 in diabetic nephropathy.

PubMed

Morris, Sidney M; You, Hanning; Gao, Ting; Vacher, Jean; Cooper, Timothy K; Awad, Alaa S

2017-10-01

Diabetes is the leading cause of end-stage renal disease, resulting in a significant health care burden and loss of economic productivity by affected individuals. Because current therapies for progression of diabetic nephropathy (DN) are only moderately successful, identification of underlying mechanisms of disease is essential to develop more effective therapies. We showed previously that inhibition of arginase using S -(2-boronoethyl)-l-cysteine (BEC) or genetic deficiency of the arginase-2 isozyme was protective against key features of nephropathy in diabetic mouse models. However, those studies did not determine whether all markers of DN were dependent only on arginase-2 expression. The objective of this study was to identify features of DN that are associated specifically with expression of arginase-1 or -2. Elevated urinary albumin excretion rate and plasma urea levels, increases in renal fibronectin mRNA levels, and decreased renal medullary blood flow were associated almost completely and specifically with arginase-2 expression, indicating that arginase-2 selectively mediates major aspects of diabetic renal injury. However, increases in renal macrophage infiltration and renal TNF-α mRNA levels occurred independent of arginase-2 expression but were almost entirely abolished by treatment with BEC, indicating a distinct role for arginase-1. We therefore generated mice with a macrophage-specific deletion of arginase-1 ( CD11b Cre / Arg1 fl/fl ). CD11b Cre / Arg1 fl/fl mice had significantly reduced macrophage infiltration but had no effect on albuminuria compared with Arg1 fl/fl mice after 12 wk of streptozotocin-induced diabetes. These results indicate that selective inhibition of arginase-2 would be effective in preventing or ameliorating major features of diabetic renal injury. Copyright © 2017 the American Physiological Society.

Multiple approaches to valuation of conservation design and low-impact development features in residential subdivisions.

PubMed

Bowman, Troy; Tyndall, John C; Thompson, Janette; Kliebenstein, James; Colletti, Joe P

2012-08-15

Residents, developers and civic officials are often faced with difficult decisions about appropriate land uses in and around metropolitan boundaries. Urban expansion brings with it the potential for negative environmental impacts, but there are alternatives, such as conservation subdivision design (CSD) or low-impact development (LID), which offer the possibility of mitigating some of these effects at the development site. Many urban planning jurisdictions across the Midwest do not currently have any examples of these designs and lack information to identify public support or barriers to use of these methods. This is a case study examining consumer value for conservation and low-impact design features in one housing market by using four different valuation techniques to estimate residents' willingness to pay for CSD and LID features in residential subdivisions. A contingent valuation survey of 1804 residents in Ames, IA assessed familiarity with and perceptions of subdivision development and used an ordered value approach to estimate willingness to pay for CSD and LID features. A majority of residents were not familiar with CSD or LID practices. Residents indicated a willingness to pay for most CSD and LID features with the exception of clustered housing. Gender, age, income, familiarity with LID practices, perceptions of attractiveness of features and the perceived effect of CSD and LID features on ease of future home sales were important factors influencing residents' willingness to pay. A hypothetical referendum measured willingness to pay for tax-funded conservation land purchases and estimated that a property tax of around $50 would be the maximum increase that would pass. Twenty-seven survey respondents participated in a subsequent series of experimental real estate negotiations that used an experimental auction mechanism to estimate willingness to pay for CSD and LID features. Participants indicated that clustered housing (with interspersed preserved forest or open space areas), rain gardens, and neighborhood streams with a forested buffer were the features they were most willing to pay for. Participants were not willing to pay for neighborhood streams without buffers. Finally, a spatial hedonic price model using 2093 homes in Ames, IA was used to estimate the effect of public and private open space on housing values. The model indicated that presence of neighborhood association-owned forest and water features as well as proximity to public parks had significant positive effects on housing prices. However, proximity to a public lake had a negative effect on home values. The four methods used in this study include both stated and revealed preference techniques. Although the relative magnitude of value expressed varied, all methods indicated that residents value CSD and LID subdivision features. Subdivision features that included explicit environmental benefits were also consistently preferred over features that did not. Familiarity with alternative designs was an important factor influencing resident willingness to pay for neighborhood features, and developers and civic officials should consider ways to educate citizens about CSD and LID development techniques to increase interest in these designs. Published by Elsevier Ltd.

Origin of the Hadži ABC structure: An ab initio study

DOE Office of Scientific and Technical Information (OSTI.GOV)

Van Hoozen, Brian L.; Petersen, Poul B.

2015-11-14

Medium and strong hydrogen bonds are well known to give rise to broad features in the vibrational spectrum often spanning several hundred wavenumbers. In some cases, these features can span over 1000 cm{sup −1} and even contain multiple broad peaks. One class of strongly hydrogen-bonded dimers that includes many different phosphinic, phosphoric, sulfinic, and selenic acid homodimers exhibits a three-peaked structure over 1500 cm{sup −1} broad. This unusual feature is often referred to as the Hadži ABC structure. The origin of this feature has been debated since its discovery in the 1950s. Only a couple of theoretical studies have attemptedmore » to interpret the origin of this feature; however, no previous study has been able to reproduce this feature from first principles. Here, we present the first ab initio calculation of the Hadži ABC structure. Using a reduced dimensionality calculation that includes four vibrational modes, we are able to reproduce the three-peak structure and much of the broadness of the feature. Our results indicate that Fermi resonances of the in-plane bend, out-of-plane bend, and combination of these bends play significant roles in explaining this feature. Much of the broadness of the feature and the ability of the OH stretch mode to couple with many overtone bending modes are captured by including an adiabatically separated dimer stretch mode in the model. This mode modulates the distance between the monomer units and accordingly the strength of the hydrogen-bonds causing the OH stretch frequency to shift from 2000 to 3000 cm{sup −1}. Using this model, we were also able to reproduce the vibrational spectrum of the deuterated isotopologue which consists of a single 500 cm{sup −1} broad feature. Whereas previous empirical studies have asserted that Fermi resonances contribute very little to this feature, our study indicates that while not appearing as a separate peak, a Fermi resonance of the in-plane bend contributes substantially to the feature.« less

Estimating local scaling properties for the classification of interstitial lung disease patterns

NASA Astrophysics Data System (ADS)

Huber, Markus B.; Nagarajan, Mahesh B.; Leinsinger, Gerda; Ray, Lawrence A.; Wismueller, Axel

2011-03-01

Local scaling properties of texture regions were compared in their ability to classify morphological patterns known as 'honeycombing' that are considered indicative for the presence of fibrotic interstitial lung diseases in high-resolution computed tomography (HRCT) images. For 14 patients with known occurrence of honeycombing, a stack of 70 axial, lung kernel reconstructed images were acquired from HRCT chest exams. 241 regions of interest of both healthy and pathological (89) lung tissue were identified by an experienced radiologist. Texture features were extracted using six properties calculated from gray-level co-occurrence matrices (GLCM), Minkowski Dimensions (MDs), and the estimation of local scaling properties with Scaling Index Method (SIM). A k-nearest-neighbor (k-NN) classifier and a Multilayer Radial Basis Functions Network (RBFN) were optimized in a 10-fold cross-validation for each texture vector, and the classification accuracy was calculated on independent test sets as a quantitative measure of automated tissue characterization. A Wilcoxon signed-rank test was used to compare two accuracy distributions including the Bonferroni correction. The best classification results were obtained by the set of SIM features, which performed significantly better than all the standard GLCM and MD features (p < 0.005) for both classifiers with the highest accuracy (94.1%, 93.7%; for the k-NN and RBFN classifier, respectively). The best standard texture features were the GLCM features 'homogeneity' (91.8%, 87.2%) and 'absolute value' (90.2%, 88.5%). The results indicate that advanced texture features using local scaling properties can provide superior classification performance in computer-assisted diagnosis of interstitial lung diseases when compared to standard texture analysis methods.

A new machine-learning method to prognosticate paraquat poisoned patients by combining coagulation, liver, and kidney indices.

PubMed

Hu, Lufeng; Li, Huaizhong; Cai, Zhennao; Lin, Feiyan; Hong, Guangliang; Chen, Huiling; Lu, Zhongqiu

2017-01-01

The prognosis of paraquat (PQ) poisoning is highly correlated to plasma PQ concentration, which has been identified as the most important index in PQ poisoning. This study investigated the predictive value of coagulation, liver, and kidney indices in prognosticating PQ-poisoning patients, when aligned with plasma PQ concentrations. Coagulation, liver, and kidney indices were first analyzed by variance analysis, receiver operating characteristic curves, and Fisher discriminant analysis. Then, a new, intelligent, machine learning-based system was established to effectively provide prognostic analysis of PQ-poisoning patients based on a combination of the aforementioned indices. In the proposed system, an enhanced extreme learning machine wrapped with a grey wolf-optimization strategy was developed to predict the risk status from a pool of 103 patients (56 males and 47 females); of these, 52 subjects were deceased and 51 alive. The proposed method was rigorously evaluated against this real-life dataset, in terms of accuracy, Matthews correlation coefficients, sensitivity, and specificity. Additionally, the feature selection was investigated to identify correlating factors for risk status. The results demonstrated that there were significant differences in the coagulation, liver, and kidney indices between deceased and surviving subjects (p<0.05). Aspartate aminotransferase, prothrombin time, prothrombin activity, total bilirubin, direct bilirubin, indirect bilirubin, alanine aminotransferase, urea nitrogen, and creatinine were the most highly correlated indices in PQ poisoning and showed statistical significance (p<0.05) in predicting PQ-poisoning prognoses. According to the feature selection, the most important correlated indices were found to be associated with aspartate aminotransferase, the aspartate aminotransferase to alanine ratio, creatinine, prothrombin time, and prothrombin activity. The method proposed here showed excellent results that were better than that produced based on blood-PQ concentration alone. These promising results indicated that the combination of these indices can provide a new avenue for prognosticating the outcome of PQ poisoning.

Structural lineament and pattern analysis of Missouri, using LANDSAT imagery

NASA Technical Reports Server (NTRS)

Martin, J. A.; Kisvarsanyi, G. (Principal Investigator)

1977-01-01

The author has identified the following significant results. Major linear, circular, and arcuate traces were observed on LANDSAT imagery of Missouri. Lineaments plotted within the state boundaries range from 20 to nearly 500 km in length. Several extend into adjoining states. Lineaments plots indicate a distinct pattern and in general reflect structural features of the Precambrian basement of the platform. Coincidence of lineaments traced from the imagery and known structural features in Missouri is high, thus supporting a causative relation between them. The lineament pattern apparently reveals a fundamental style of the deformation of the intracontinental craton. Dozens of heretofore unknown linear features related to epirogenic movements and deformation of this segment of the continental crust were delineated. Lineaments and mineralization are interrelated in a geometrically classifiable pattern.

An alternative mechanism for production of emission features in some infrared objects

NASA Technical Reports Server (NTRS)

Apruzese, J. P.

1975-01-01

Two dust-envelope models of the M supergiant VX Sgr, which exhibits a prominent emission feature at 10 microns, are presented. The models indicate that, for certain envelope sizes, the presence of the observed emission feature does not necessarily indicate that the emitting grains possess a similar feature in their emissivity profile. The mechanism which may in some cases be producing the observed emission feature is discussed.

Student Perceptions of the Value of Career Development Learning to a Work-Integrated Learning Course in Exercise Science

ERIC Educational Resources Information Center

Reddan, Gregory; Rauchle, Maja

2012-01-01

Work-integrated learning has become a significant feature of Australian universities over the past decade. Earlier research indicates that some form of career development is essential to prepare undergraduate students for a competitive employment market. The 2008 National Association of Graduate Careers Advisory Services (NAGCAS) Symposium sought…

Developing regeneration in woodlots at Gettysburg National Military Park

Treesearch

Todd W. Bowersox; Gerald L. Storm; Walter M. Tzilkowski

1993-01-01

Woodlots are significant features of the historic scene at Gettysburg National Military Park, Pennsylvania. Recent inventories of these historic woodlots indicated a general lack of seedling recruitment in the uneven-aged stands with a mature mixed oak overstory and a midstory of ash-cherry-dogwood-hickory. Seedling-sized stems of shrub and tree species were abundant,...

Exploration of the canyon-incised continental margin of the northeastern United States reveals dynamic habitats and diverse communities

USGS Publications Warehouse

Quattrini, Andrea; Nizinski, Martha S.; Chaytor, Jason; Demopoulos, Amanda W.J.; Roark, E. Brendan; France, Scott; Moore, Jon A.; Heyl, Taylor P.; Auster, Peter J.; Ruppel, Carolyn D.; Elliott, Kelley P.; Kennedy, Brian R.C.; Lobecker, Elizabeth A.; Skarke, Adam; Shank, Timothy M.

2015-01-01

The continental margin off the northeastern United States (NEUS) contains numerous, topographically complex features that increase habitat heterogeneity across the region. However, the majority of these rugged features have never been surveyed, particularly using direct observations. During summer 2013, 31 Remotely-Operated Vehicle (ROV) dives were conducted from 494 to 3271 m depth across a variety of seafloor features to document communities and to infer geological processes that produced such features. The ROV surveyed six broad-scale habitat features, consisting of shelf-breaching canyons, slope-sourced canyons, inter-canyon areas, open-slope/landslide-scar areas, hydrocarbon seeps, and Mytilus Seamount. Four previously unknown chemosynthetic communities dominated by Bathymodiolus mussels were documented. Seafloor methane hydrate was observed at two seep sites. Multivariate analyses indicated that depth and broad-scale habitat significantly influenced megafaunal coral (58 taxa), demersal fish (69 taxa), and decapod crustacean (34 taxa) assemblages. Species richness of fishes and crustaceans significantly declined with depth, while there was no relationship between coral richness and depth. Turnover in assemblage structure occurred on the middle to lower slope at the approximate boundaries of water masses found previously in the region. Coral species richness was also an important variable explaining variation in fish and crustacean assemblages. Coral diversity may serve as an indicator of habitat suitability and variation in available niche diversity for these taxonomic groups. Our surveys added 24 putative coral species and three fishes to the known regional fauna, including the black coral Telopathes magna, the octocoral Metallogorgia melanotrichosand the fishes Gaidropsarus argentatus, Guttigadus latifrons, and Lepidion guentheri. Marine litter was observed on 81% of the dives, with at least 12 coral colonies entangled in debris. While initial exploration revealed the NEUS region to be both geologically dynamic and biologically diverse, further research into the abiotic conditions and the biotic interactions that influence species abundance and distribution is needed.

Exploration of the Canyon-Incised Continental Margin of the Northeastern United States Reveals Dynamic Habitats and Diverse Communities.

PubMed

Quattrini, Andrea M; Nizinski, Martha S; Chaytor, Jason D; Demopoulos, Amanda W J; Roark, E Brendan; France, Scott C; Moore, Jon A; Heyl, Taylor; Auster, Peter J; Kinlan, Brian; Ruppel, Carolyn; Elliott, Kelley P; Kennedy, Brian R C; Lobecker, Elizabeth; Skarke, Adam; Shank, Timothy M

2015-01-01

The continental margin off the northeastern United States (NEUS) contains numerous, topographically complex features that increase habitat heterogeneity across the region. However, the majority of these rugged features have never been surveyed, particularly using direct observations. During summer 2013, 31 Remotely-Operated Vehicle (ROV) dives were conducted from 494 to 3271 m depth across a variety of seafloor features to document communities and to infer geological processes that produced such features. The ROV surveyed six broad-scale habitat features, consisting of shelf-breaching canyons, slope-sourced canyons, inter-canyon areas, open-slope/landslide-scar areas, hydrocarbon seeps, and Mytilus Seamount. Four previously unknown chemosynthetic communities dominated by Bathymodiolus mussels were documented. Seafloor methane hydrate was observed at two seep sites. Multivariate analyses indicated that depth and broad-scale habitat significantly influenced megafaunal coral (58 taxa), demersal fish (69 taxa), and decapod crustacean (34 taxa) assemblages. Species richness of fishes and crustaceans significantly declined with depth, while there was no relationship between coral richness and depth. Turnover in assemblage structure occurred on the middle to lower slope at the approximate boundaries of water masses found previously in the region. Coral species richness was also an important variable explaining variation in fish and crustacean assemblages. Coral diversity may serve as an indicator of habitat suitability and variation in available niche diversity for these taxonomic groups. Our surveys added 24 putative coral species and three fishes to the known regional fauna, including the black coral Telopathes magna, the octocoral Metallogorgia melanotrichos and the fishes Gaidropsarus argentatus, Guttigadus latifrons, and Lepidion guentheri. Marine litter was observed on 81% of the dives, with at least 12 coral colonies entangled in debris. While initial exploration revealed the NEUS region to be both geologically dynamic and biologically diverse, further research into the abiotic conditions and the biotic interactions that influence species abundance and distribution is needed.

Exploration of the Canyon-Incised Continental Margin of the Northeastern United States Reveals Dynamic Habitats and Diverse Communities

PubMed Central

Quattrini, Andrea M.; Nizinski, Martha S.; Chaytor, Jason D.; Demopoulos, Amanda W. J.; Roark, E. Brendan; France, Scott C.; Moore, Jon A.; Heyl, Taylor; Auster, Peter J.; Kinlan, Brian; Ruppel, Carolyn; Elliott, Kelley P.; Kennedy, Brian R.C.; Lobecker, Elizabeth; Skarke, Adam; Shank, Timothy M.

2015-01-01

The continental margin off the northeastern United States (NEUS) contains numerous, topographically complex features that increase habitat heterogeneity across the region. However, the majority of these rugged features have never been surveyed, particularly using direct observations. During summer 2013, 31 Remotely-Operated Vehicle (ROV) dives were conducted from 494 to 3271 m depth across a variety of seafloor features to document communities and to infer geological processes that produced such features. The ROV surveyed six broad-scale habitat features, consisting of shelf-breaching canyons, slope-sourced canyons, inter-canyon areas, open-slope/landslide-scar areas, hydrocarbon seeps, and Mytilus Seamount. Four previously unknown chemosynthetic communities dominated by Bathymodiolus mussels were documented. Seafloor methane hydrate was observed at two seep sites. Multivariate analyses indicated that depth and broad-scale habitat significantly influenced megafaunal coral (58 taxa), demersal fish (69 taxa), and decapod crustacean (34 taxa) assemblages. Species richness of fishes and crustaceans significantly declined with depth, while there was no relationship between coral richness and depth. Turnover in assemblage structure occurred on the middle to lower slope at the approximate boundaries of water masses found previously in the region. Coral species richness was also an important variable explaining variation in fish and crustacean assemblages. Coral diversity may serve as an indicator of habitat suitability and variation in available niche diversity for these taxonomic groups. Our surveys added 24 putative coral species and three fishes to the known regional fauna, including the black coral Telopathes magna, the octocoral Metallogorgia melanotrichos and the fishes Gaidropsarus argentatus, Guttigadus latifrons, and Lepidion guentheri. Marine litter was observed on 81% of the dives, with at least 12 coral colonies entangled in debris. While initial exploration revealed the NEUS region to be both geologically dynamic and biologically diverse, further research into the abiotic conditions and the biotic interactions that influence species abundance and distribution is needed. PMID:26509818

Neural Architecture for Feature Binding in Visual Working Memory.

PubMed

Schneegans, Sebastian; Bays, Paul M

2017-04-05

Binding refers to the operation that groups different features together into objects. We propose a neural architecture for feature binding in visual working memory that employs populations of neurons with conjunction responses. We tested this model using cued recall tasks, in which subjects had to memorize object arrays composed of simple visual features (color, orientation, and location). After a brief delay, one feature of one item was given as a cue, and the observer had to report, on a continuous scale, one or two other features of the cued item. Binding failure in this task is associated with swap errors, in which observers report an item other than the one indicated by the cue. We observed that the probability of swapping two items strongly correlated with the items' similarity in the cue feature dimension, and found a strong correlation between swap errors occurring in spatial and nonspatial report. The neural model explains both swap errors and response variability as results of decoding noisy neural activity, and can account for the behavioral results in quantitative detail. We then used the model to compare alternative mechanisms for binding nonspatial features. We found the behavioral results fully consistent with a model in which nonspatial features are bound exclusively via their shared location, with no indication of direct binding between color and orientation. These results provide evidence for a special role of location in feature binding, and the model explains how this special role could be realized in the neural system. SIGNIFICANCE STATEMENT The problem of feature binding is of central importance in understanding the mechanisms of working memory. How do we remember not only that we saw a red and a round object, but that these features belong together to a single object rather than to different objects in our environment? Here we present evidence for a neural mechanism for feature binding in working memory, based on encoding of visual information by neurons that respond to the conjunction of features. We find clear evidence that nonspatial features are bound via space: we memorize directly where a color or an orientation appeared, but we memorize which color belonged with which orientation only indirectly by virtue of their shared location. Copyright © 2017 Schneegans and Bays.

Lipidomic profiling reveals distinct differences in plasma lipid composition in healthy, prediabetic, and type 2 diabetic individuals

PubMed Central

Zhong, Huanzi; Fang, Chao; Fan, Yanqun; Lu, Yan; Wen, Bo; Ren, Huahui; Hou, Guixue; Yang, Fangming; Xie, Hailiang; Jie, Zhuye; Peng, Ye; Ye, Zhiqiang; Wu, Jiegen; Zi, Jin; Zhao, Guoqing; Chen, Jiayu; Bao, Xiao; Hu, Yihe; Gao, Yan; Zhang, Jun; Yang, Huanming; Wang, Jian; Madsen, Lise; Kristiansen, Karsten

2017-01-01

Abstract The relationship between dyslipidemia and type 2 diabetes mellitus (T2D) has been extensively reported, but the global lipid profiles, especially in the East Asia population, associated with the development of T2D remain to be characterized. Liquid chromatography coupled to tandem mass spectrometry was applied to detect the global lipidome in the fasting plasma of 293 Chinese individuals, including 114 T2D patients, 81 prediabetic subjects, and 98 individuals with normal glucose tolerance (NGT). Both qualitative and quantitative analyses revealed a gradual change in plasma lipid features with T2D patients exhibiting characteristics close to those of prediabetic individuals, whereas they differed significantly from individuals with NGT. We constructed and validated a random forest classifier with 28 lipidomic features that effectively discriminated T2D from NGT or prediabetes. Most of the selected features significantly correlated with diabetic clinical indices. Hydroxybutyrylcarnitine was positively correlated with fasting plasma glucose, 2-hour postprandial glucose, glycated hemoglobin, and insulin resistance index (HOMA-IR). Lysophosphatidylcholines such as lysophosphatidylcholine (18:0), lysophosphatidylcholine (18:1), and lysophosphatidylcholine (18:2) were all negatively correlated with HOMA-IR. The altered plasma lipidome in Chinese T2D and prediabetic subjects suggests that lipid features may play a role in the pathogenesis of T2D and that such features may provide a basis for evaluating risk and monitoring disease development. PMID:28505362

MiRNA-miRNA synergistic network: construction via co-regulating functional modules and disease miRNA topological features.

PubMed

Xu, Juan; Li, Chuan-Xing; Li, Yong-Sheng; Lv, Jun-Ying; Ma, Ye; Shao, Ting-Ting; Xu, Liang-De; Wang, Ying-Ying; Du, Lei; Zhang, Yun-Peng; Jiang, Wei; Li, Chun-Quan; Xiao, Yun; Li, Xia

2011-02-01

Synergistic regulations among multiple microRNAs (miRNAs) are important to understand the mechanisms of complex post-transcriptional regulations in humans. Complex diseases are affected by several miRNAs rather than a single miRNA. So, it is a challenge to identify miRNA synergism and thereby further determine miRNA functions at a system-wide level and investigate disease miRNA features in the miRNA-miRNA synergistic network from a new view. Here, we constructed a miRNA-miRNA functional synergistic network (MFSN) via co-regulating functional modules that have three features: common targets of corresponding miRNA pairs, enriched in the same gene ontology category and close proximity in the protein interaction network. Predicted miRNA synergism is validated by significantly high co-expression of functional modules and significantly negative regulation to functional modules. We found that the MFSN exhibits a scale free, small world and modular architecture. Furthermore, the topological features of disease miRNAs in the MFSN are distinct from non-disease miRNAs. They have more synergism, indicating their higher complexity of functions and are the global central cores of the MFSN. In addition, miRNAs associated with the same disease are close to each other. The structure of the MFSN and the features of disease miRNAs are validated to be robust using different miRNA target data sets.

Lipid-lowering drugs (statins) and peripheral neuropathy.

PubMed

Emad, Mohammadreza; Arjmand, Hosein; Farpour, Hamid Reza; Kardeh, Bahareh

2018-03-01

Peripheral neuropathy is a disorder with often unknown causes. Some drugs, including statins, are proposed to be among the causes of peripheral neuropathy. This study aimed at evaluating this condition by electrodiagnostic study among patients who had received statins. This case-control study was conducted in Shiraz, Iran in 2015, and included 39 patients aged 35-55 who had received statins for at least 6 months, and 39 healthy matched controls. Using electrodiagnosis, the sensory and motor wave features (amplitude, latency and nerve conduction velocity) of the peripheral nerves (Median, Ulnar, Tibial, Sural, and Peroneal) were evaluated among the subjects. Data were analyzed using SPSS software and p<0.05 was considered statistically significant. Regarding the occurrence of neuropathy, there were no significant differences in any of the definitions presented for peripheral neuropathy. However, the difference was close to significance for one definition [2 abnormalities in 2 nerves (p=0.055)]. Regarding mean values of the features, significant differences were observed in two features: amplitude of the peroneal motor nerve (p=0.048) and amplitude of the sural sensory nerve (p=0.036). Since statins are widely used, awareness regarding their side-effects would lead to better treatment. Even though no significant differences were found between the groups regarding the occurrence of peripheral neuropathy, there were significant differences in amplitudes of the sural sensory response and the peroneal motor response. This indicates the involvement of peripheral nerves. Therefore, we recommend that patients and physicians should be informed about the possible symptoms of this condition.

The applicability of ERTS-1 data covering the major landforms of Kenya. [landforms, vegetation, soils, forests

NASA Technical Reports Server (NTRS)

Omino, J. H. O. (Principal Investigator)

1973-01-01

The author has identified the following significant results. Five investigators report on the applicability of ERTS-1 data covering the major landforms of Kenya. Deficiencies due to lack of equipment, repetitive coverage and interpretation know-how are also reported on. Revision of lake shorelines is an immediate benefit. Basement system metasediments are rapidly differentiated, but dune areas are not readily distinguishable from sandy soils. Forest, moorland, high altitude grass, tea, and conifer plantations are readily distinguished, with podocarpus forest especially distinguishable from podocarpus/juniperus forest. In the arid areas physiographic features, indicating the major soil types, are readily identified and mapped. Preliminary vegetation type analysis in the Mara Game Reserve indicates that in a typical savannah area about 36% of the vegetation types are distinguishable at a scale of 1:1 million as well as drainage patterns and terrain features.

Multitasking: Effects of processing multiple auditory feature patterns

PubMed Central

Miller, Tova; Chen, Sufen; Lee, Wei Wei; Sussman, Elyse S.

2016-01-01

ERPs and behavioral responses were measured to assess how task-irrelevant sounds interact with task processing demands and affect the ability to monitor and track multiple sound events. Participants listened to four-tone sequential frequency patterns, and responded to frequency pattern deviants (reversals of the pattern). Irrelevant tone feature patterns (duration and intensity) and respective pattern deviants were presented together with frequency patterns and frequency pattern deviants in separate conditions. Responses to task-relevant and task-irrelevant feature pattern deviants were used to test processing demands for irrelevant sound input. Behavioral performance was significantly better when there were no distracting feature patterns. Errors primarily occurred in response to the to-be-ignored feature pattern deviants. Task-irrelevant elicitation of ERP components was consistent with the error analysis, indicating a level of processing for the irrelevant features. Task-relevant elicitation of ERP components was consistent with behavioral performance, demonstrating a “cost” of performance when there were two feature patterns presented simultaneously. These results provide evidence that the brain tracked the irrelevant duration and intensity feature patterns, affecting behavioral performance. Overall, our results demonstrate that irrelevant informational streams are processed at a cost, which may be considered a type of multitasking that is an ongoing, automatic processing of taskirrelevant sensory events. PMID:25939456

HCMM: Soil moisture in relation to geologic structure and lithology, northern California. [Sacremento Valley

NASA Technical Reports Server (NTRS)

Rich, E. I. (Principal Investigator)

1979-01-01

The author has identified the following significant results. A preliminary analysis of the HCMM imagery of the project area indicated that locally some differentiation of lithologic units within the Northern Coast Range may be possible. Of significance, however, was a thermally cool linear area that appeared on the 30 May 1978 Nite-IR. This linear feature seemed to coincide with the Bear Mt. Fault and with the axis of the Chico Monocline along the eastern margin of the Sacramento Valley.

Use of Nintendo Wii Balance Board for posturographic analysis of Multiple Sclerosis patients with minimal balance impairment.

PubMed

Severini, Giacomo; Straudi, Sofia; Pavarelli, Claudia; Da Roit, Marco; Martinuzzi, Carlotta; Di Marco Pizzongolo, Laura; Basaglia, Nino

2017-03-11

The Wii Balance Board (WBB) has been proposed as an inexpensive alternative to laboratory-grade Force Plates (FP) for the instrumented assessment of balance. Previous studies have reported a good validity and reliability of the WBB for estimating the path length of the Center of Pressure. Here we extend this analysis to 18 balance related features extracted from healthy subjects (HS) and individuals affected by Multiple Sclerosis (MS) with minimal balance impairment. Eighteen MS patients with minimal balance impairment (Berg Balance Scale 53.3 ± 3.1) and 18 age-matched HS were recruited in this study. All subjects underwent instrumented balance tests on the FP and WBB consisting of quiet standing with the eyes open and closed. Linear correlation analysis and Bland-Altman plots were used to assess relations between path lengths estimated using the WBB and the FP. 18 features were extracted from the instrumented balance tests. Statistical analysis was used to assess significant differences between the features estimated using the WBB and the FP and between HS and MS. The Spearman correlation coefficient was used to evaluate the validity and the Intraclass Correlation Coefficient was used to assess the reliability of WBB measures with respect to the FP. Classifiers based on Support Vector Machines trained on the FP and WBB features were used to assess the ability of both devices to discriminate between HS and MS. We found a significant linear relation between the path lengths calculated from the WBB and the FP indicating an overestimation of these parameters in the WBB. We observed significant differences in the path lengths between FP and WBB in most conditions. However, significant differences were not found for the majority of the other features. We observed the same significant differences between the HS and MS populations across the two measurement systems. Validity and reliability were moderate-to-high for all the analyzed features. Both the FP and WBB trained classifier showed similar classification performance (>80%) when discriminating between HS and MS. Our results support the observation that the WBB, although not suitable for obtaining absolute measures, could be successfully used in comparative analysis of different populations.

Humidity-Dependent Bacterial Cells Functional Morphometry Investigations Using Atomic Force Microscope

PubMed Central

Nikiyan, Hike; Vasilchenko, Alexey; Deryabin, Dmitry

2010-01-01

The effect of a relative humidity (RH) in a range of 93–65% on morphological and elastic properties of Bacillus cereus and Escherichia coli cells was evaluated using atomic force microscopy. It is shown that gradual dehumidification of bacteria environment has no significant effect on cell dimensional features and considerably decreases them only at 65% RH. The increasing of the bacteria cell wall roughness and elasticity occurs at the same time. Observed changes indicate that morphological properties of B. cereus are rather stable in wide range of relative humidity, whereas E. coli are more sensitive to drying, significantly increasing roughness and stiffness parameters at RH ≤ 84% RH. It is discussed the dependence of the response features on differences in cell wall structure of gram-positive and gram-negative bacterial cells. PMID:20652040

Evaluation of TV commercials using neurophysiological responses.

PubMed

Yang, Taeyang; Lee, Do-Young; Kwak, Youngshin; Choi, Jinsook; Kim, Chajoong; Kim, Sung-Phil

2015-04-24

In recent years, neuroscientific knowledge has been applied to marketing as a novel and efficient means to comprehend the cognitive and behavioral aspects of consumers. A number of studies have attempted to evaluate media contents, especially TV commercials using various neuroimaging techniques such as electroencephalography (EEG). Yet neurophysiological examination of detailed cognitive and affective responses in viewers is still required to provide practical information to marketers. Here, this study develops a method to analyze temporal patterns of EEG data and extract affective and cognitive indices such as happiness, surprise, and attention for TV commercial evaluation. Twenty participants participated in the study. We developed the neurophysiological indices for TV commercial evaluation using classification model. Specifically, these model-based indices were customized using individual EEG features. We used a video game for developing the index of attention and four video clips for developing indices of happiness and surprise. Statistical processes including one-way analyses of variance (ANOVA) and the cross validation scheme were used to select EEG features for each index. The EEG features were composed of the combinations of spectral power at selected channels from the cross validation for each individual. The Fisher's linear discriminant classifier (FLDA) was used to estimate each neurophysiological index during viewing four different TV commercials. Post hoc behavioral responses of preference, short-term memory, and recall were measured. Behavioral results showed significant differences for all preference, short-term memory rates, and recall rates between commercials, leading to a 'high-ranked' commercial group and a 'low-ranked' group (P < 0.05). Neural estimation of happiness results revealed a significant difference between the high-ranked and the low-ranked commercials in happiness index (P < 0.01). The order of rankings based on happiness and attention matched well with the order of behavioral response rankings. In the elapsed-time analysis of the highest-ranked commercial, we could point to visual and auditory semantic structures of the commercial that induced increases in the happiness index. Our results demonstrated that the neurophysiological indices developed in this study may provide a useful tool for evaluating TV commercials.

Oxygen cost of treadmill and over-ground walking in mildly disabled persons with multiple sclerosis

PubMed Central

Suh, Yoojin; Dlugonski, Deirdre; Weikert, Madeline; Agiovlasitis, Stamatis; Fernhall, Bo; Goldman, Myla

2011-01-01

Walking impairment is a ubiquitous feature of multiple sclerosis (MS) and the O2 cost of walking might quantify this dysfunction in mild MS. This paper examined the difference in O2 cost of walking between persons with MS who have mild disability and healthy controls and the correlation between the O2 cost of walking and disability. Study 1 included 18 persons with mild MS and 18 controls and indicated that the O2 cost of walking was significantly higher in MS than controls and that disability was significantly associated with the O2 cost of slow, moderate, and fast treadmill walking. Study 2 included 24 persons with mild MS and indicated that disability was significantly correlated with O2 cost of comfortable, fast, and slow over-ground walking. We provide evidence that the O2 cost of walking is an indicator of walking dysfunction in mildly disabled persons with MS and should be considered in clinical research and practice. PMID:20798968

Oxygen cost of treadmill and over-ground walking in mildly disabled persons with multiple sclerosis.

PubMed

Motl, Robert W; Suh, Yoojin; Dlugonski, Deirdre; Weikert, Madeline; Agiovlasitis, Stamatis; Fernhall, Bo; Goldman, Myla

2011-04-01

Walking impairment is a ubiquitous feature of multiple sclerosis (MS) and the O(2) cost of walking might quantify this dysfunction in mild MS. This paper examined the difference in O(2) cost of walking between persons with MS who have mild disability and healthy controls and the correlation between the O(2) cost of walking and disability. Study 1 included 18 persons with mild MS and 18 controls and indicated that the O(2) cost of walking was significantly higher in MS than controls and that disability was significantly associated with the O(2) cost of slow, moderate, and fast treadmill walking. Study 2 included 24 persons with mild MS and indicated that disability was significantly correlated with O(2) cost of comfortable, fast, and slow over-ground walking. We provide evidence that the O(2) cost of walking is an indicator of walking dysfunction in mildly disabled persons with MS and should be considered in clinical research and practice.

Mass movement and storms in the drainage basin of Redwood Creek, Humboldt County, California: a progress report

USGS Publications Warehouse

Harden, Deborah Reid; Janda, Richard J.; Nolan, K. Michael

1978-01-01

Numerous active landslides are clearly significant contributors to high sediment loads in the Redwood Creek basin. Field and aerial-photograph inspections indicate that large mass-movement features, such as earthflows and massive streamside debris slides, occur primarily in terrain underlain by unmetamorphosed or slightly metamorphosed sedimentary rocks. These features cannot account for stream sediment derived from schist. Observed lithologic heterogeneity of stream sediment therefore suggests that large-scale mass movement is only one part of a complex suite of processes supplying sediment to streams in this basin. Other significant sediment contributors include various forms of fluvial erosion and small-scale discrete mass failures, particularly on oversteepened hillslopes adjacent to perennial streams. Photo-interpretive studies of landslide and timber-harvest history adjacent to Redwood Creek, together with analysis of regional precipitation and runoff records for six flood-producing storms between 1953 and 1975, indicate that loci and times of significant streamside landsliding are influenced by both local storm intensity and streamside logging. Analysis of rainfall records and historic accounts indicates that the individual storms comprising a late-19th-century series of storms in northwestern California were similar in magnitude and spacing to those of the past 25 years. The recent storms apparently initiated more streamside landslides than comparable earlier storms, which occurred prior to extensive road construction and timber harvest. Field observations and repeated surveys of stake arrays at 10 sites in the basin indicate that earthflows are especially active during prolonged periods of moderate rainfall; but that during brief intense storms, fluvial processes are the dominant erosion mechanism. Stake movement occurs mostly during wet winter months. Spring and summer movement was detected at some moist streamside sites. Surveys of stake arrays in two recently logged areas did not indicate exceptionally rapid rates of movement in three years following timber harvest.

TU-CD-BRB-04: Automated Radiomic Features Complement the Prognostic Value of VASARI in the TCGA-GBM Dataset

DOE Office of Scientific and Technical Information (OSTI.GOV)

Velazquez, E Rios; Narayan, V; Grossmann, P

2015-06-15

Purpose: To compare the complementary prognostic value of automated Radiomic features to that of radiologist-annotated VASARI features in TCGA-GBM MRI dataset. Methods: For 96 GBM patients, pre-operative MRI images were obtained from The Cancer Imaging Archive. The abnormal tumor bulks were manually defined on post-contrast T1w images. The contrast-enhancing and necrotic regions were segmented using FAST. From these sub-volumes and the total abnormal tumor bulk, a set of Radiomic features quantifying phenotypic differences based on the tumor intensity, shape and texture, were extracted from the post-contrast T1w images. Minimum-redundancy-maximum-relevance (MRMR) was used to identify the most informative Radiomic, VASARI andmore » combined Radiomic-VASARI features in 70% of the dataset (training-set). Multivariate Cox-proportional hazards models were evaluated in 30% of the dataset (validation-set) using the C-index for OS. A bootstrap procedure was used to assess significance while comparing the C-Indices of the different models. Results: Overall, the Radiomic features showed a moderate correlation with the radiologist-annotated VASARI features (r = −0.37 – 0.49); however that correlation was stronger for the Tumor Diameter and Proportion of Necrosis VASARI features (r = −0.71 – 0.69). After MRMR feature selection, the best-performing Radiomic, VASARI, and Radiomic-VASARI Cox-PH models showed a validation C-index of 0.56 (p = NS), 0.58 (p = NS) and 0.65 (p = 0.01), respectively. The combined Radiomic-VASARI model C-index was significantly higher than that obtained from either the Radiomic or VASARI model alone (p = <0.001). Conclusion: Quantitative volumetric and textural Radiomic features complement the qualitative and semi-quantitative annotated VASARI feature set. The prognostic value of informative qualitative VASARI features such as Eloquent Brain and Multifocality is increased with the addition of quantitative volumetric and textural features from the contrast-enhancing and necrotic tumor regions. These results should be further evaluated in larger validation cohorts.« less

A PCA aided cross-covariance scheme for discriminative feature extraction from EEG signals.

PubMed

Zarei, Roozbeh; He, Jing; Siuly, Siuly; Zhang, Yanchun

2017-07-01

Feature extraction of EEG signals plays a significant role in Brain-computer interface (BCI) as it can significantly affect the performance and the computational time of the system. The main aim of the current work is to introduce an innovative algorithm for acquiring reliable discriminating features from EEG signals to improve classification performances and to reduce the time complexity. This study develops a robust feature extraction method combining the principal component analysis (PCA) and the cross-covariance technique (CCOV) for the extraction of discriminatory information from the mental states based on EEG signals in BCI applications. We apply the correlation based variable selection method with the best first search on the extracted features to identify the best feature set for characterizing the distribution of mental state signals. To verify the robustness of the proposed feature extraction method, three machine learning techniques: multilayer perceptron neural networks (MLP), least square support vector machine (LS-SVM), and logistic regression (LR) are employed on the obtained features. The proposed methods are evaluated on two publicly available datasets. Furthermore, we evaluate the performance of the proposed methods by comparing it with some recently reported algorithms. The experimental results show that all three classifiers achieve high performance (above 99% overall classification accuracy) for the proposed feature set. Among these classifiers, the MLP and LS-SVM methods yield the best performance for the obtained feature. The average sensitivity, specificity and classification accuracy for these two classifiers are same, which are 99.32%, 100%, and 99.66%, respectively for the BCI competition dataset IVa and 100%, 100%, and 100%, for the BCI competition dataset IVb. The results also indicate the proposed methods outperform the most recently reported methods by at least 0.25% average accuracy improvement in dataset IVa. The execution time results show that the proposed method has less time complexity after feature selection. The proposed feature extraction method is very effective for getting representatives information from mental states EEG signals in BCI applications and reducing the computational complexity of classifiers by reducing the number of extracted features. Copyright © 2017 Elsevier B.V. All rights reserved.

Obsessive-compulsive personality disorder features and response to behavioral therapy for insomnia among patients with hypnotic-dependent insomnia.

PubMed

Petrov, Megan E; Emert, Sarah E; Lichstein, Kenneth L

2018-06-05

To compare therapeutic response to behavioral therapy for insomnia (BT-I) among hypnotic-dependent insomnia (HDI) patients with and without Cluster C personality disorders. Twenty-three adults with HDI (17 females), aged between 33 and 68 (M = 53; SD = 9.9) were included in the study. Participants completed a personality disorder assessment (baseline), as well as sleep diaries, polysomnography (PSG), and an insomnia severity assessment (baseline, posttreatment, and one-year follow-up). Treatment consisted of eight weeks of individual BT-I and gradual hypnotic medication withdrawal. Multilevel mixed-effects linear regression models examined the interaction between study visit and Cluster C personality disorders status on treatment response to BT-I. Obsessive-compulsive personality disorder (OCPD) was the most prevalent of the Cluster C personality disorders with 38% (n = 8) of participants meeting criteria. There were no significant treatment differences by OCPD status across time as measured by sleep diaries and insomnia severity status. However, there were significant treatment differences by OCPD status by one-year follow-up on PSG outcomes, indicating that patients with OCPD status had shorter and more disrupted sleep than patients without OCPD status. Based on self-reported sleep measures, patients with insomnia and features of OCPD responded equivalently to BT-I at one-year follow-up compared to patients without features of OCPD. However, polysomnography outcomes indicated objective sleep deteriorated in these patients, which may suggest greater vulnerability to relapse.

Dark matter phenomenology of high-speed galaxy cluster collisions

DOE PAGES

Mishchenko, Yuriy; Ji, Chueng-Ryong

2017-07-29

Here, we perform a general computational analysis of possible post-collision mass distributions in high-speed galaxy cluster collisions in the presence of self-interacting dark matter. Using this analysis, we show that astrophysically weakly self-interacting dark matter can impart subtle yet measurable features in the mass distributions of colliding galaxy clusters even without significant disruptions to the dark matter halos of the colliding galaxy clusters themselves. Most profound such evidence is found to reside in the tails of dark matter halos’ distributions, in the space between the colliding galaxy clusters. Such features appear in our simulations as shells of scattered dark mattermore » expanding in alignment with the outgoing original galaxy clusters, contributing significant densities to projected mass distributions at large distances from collision centers and large scattering angles of up to 90°. Our simulations indicate that as much as 20% of the total collision’s mass may be deposited into such structures without noticeable disruptions to the main galaxy clusters. Such structures at large scattering angles are forbidden in purely gravitational high-speed galaxy cluster collisions.Convincing identification of such structures in real colliding galaxy clusters would be a clear indication of the self-interacting nature of dark matter. Our findings may offer an explanation for the ring-like dark matter feature recently identified in the long-range reconstructions of the mass distribution of the colliding galaxy cluster CL0024+017.« less

Dark matter phenomenology of high-speed galaxy cluster collisions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mishchenko, Yuriy; Ji, Chueng-Ryong

Here, we perform a general computational analysis of possible post-collision mass distributions in high-speed galaxy cluster collisions in the presence of self-interacting dark matter. Using this analysis, we show that astrophysically weakly self-interacting dark matter can impart subtle yet measurable features in the mass distributions of colliding galaxy clusters even without significant disruptions to the dark matter halos of the colliding galaxy clusters themselves. Most profound such evidence is found to reside in the tails of dark matter halos’ distributions, in the space between the colliding galaxy clusters. Such features appear in our simulations as shells of scattered dark mattermore » expanding in alignment with the outgoing original galaxy clusters, contributing significant densities to projected mass distributions at large distances from collision centers and large scattering angles of up to 90°. Our simulations indicate that as much as 20% of the total collision’s mass may be deposited into such structures without noticeable disruptions to the main galaxy clusters. Such structures at large scattering angles are forbidden in purely gravitational high-speed galaxy cluster collisions.Convincing identification of such structures in real colliding galaxy clusters would be a clear indication of the self-interacting nature of dark matter. Our findings may offer an explanation for the ring-like dark matter feature recently identified in the long-range reconstructions of the mass distribution of the colliding galaxy cluster CL0024+017.« less

Bulk Hydrogen Content OF High-Silica Rocks in Gale Crater With the Active Dynamic Albedo of Neutrons Experiment

NASA Technical Reports Server (NTRS)

Gabriel, T. S. J.; Hardgrove, C.; Litvak, M.; Mitrofanov, I.; Boynton, W. V.; Fedosov, F.; Golovin, D.; Jun, I.; Mischna, M.; Tate, C. G.;

Development of an active boring bar for increased chatter immunity

DOE Office of Scientific and Technical Information (OSTI.GOV)

Redmond, J.; Barney, P.; Smith, D.

The development and initial evaluation of a prototype boring bar featuring active vibration control for increased chatter immunity is described. The significance of active damping both normal and tangential to the workpiece surface is evaluated, indicating the need for two axis control to ensure adequate performance over expected variations in tool mounting procedures. The prototype tool features a commercially available boring bar modified to accommodate four PZT stack actuators for two axis bending control. Measured closed-loop dynamics are combined with a computer model of the boring process to simulate increased metal removal rate and improved workpiece surface finish through activemore » control.« less

Comparison of psychotic bipolar disorder, schizoaffective disorder, and schizophrenia: an international, multisite study.

PubMed

Tondo, L; Vázquez, G H; Baethge, C; Baronessa, C; Bolzani, L; Koukopoulos, A; Mazzarini, L; Murru, A; Pacchiarotti, I; Pinna, M; Salvatore, P; Sani, G; Selle, V; Spalletta, G; Girardi, P; Tohen, M; Vieta, E; Baldessarini, R J

2016-01-01

Nosological distinctions among schizoaffective disorder (SA), bipolar I disorder with psychotic features (BDp), and schizophrenia (SZ) remain unresolved. We compared 2269 subjects with psychotic features in DSM-IV-TR diagnoses (1435 BDp, 463 SZ, 371 SA) from 8 collaborating international sites, by 12 sociodemographic and clinical measures, all between diagnostic pairs. In bivariate comparisons, SA was consistently intermediate between BDp and SZ for 11/12 features (except onset stressors), and SZ vs. BDp differed in all 12 factors. SA differed from both BDp and SZ in 9/12 factors: SA and BDp were similar in education and suicidal ideation or acts; SA and SZ were similar in education, onset stressors, and substance abuse. Meta-analytic comparisons of diagnostic pairs for 10 categorical factors indicated similar differences of SA from both SZ and BDp. Multivariate modeling indicated significantly independent differences between BDp and SZ (8 factors), SA vs. SZ (5), and BDp vs. SA (3). Measurement variance was similar for all diagnoses. SA was consistently intermediate between BDp and SZ. The three diagnostic groups ranked: BDp > SA > SZ related to lesser morbidity or disability. The findings are not consistent with a dyadic Kraepelinian categorization, although the considerable overlap among the three DSM-IV diagnostic groups indicates uncertain boundaries if they represent distinct disorders. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Waveform fitting and geometry analysis for full-waveform lidar feature extraction

NASA Astrophysics Data System (ADS)

Tsai, Fuan; Lai, Jhe-Syuan; Cheng, Yi-Hsiu

2016-10-01

This paper presents a systematic approach that integrates spline curve fitting and geometry analysis to extract full-waveform LiDAR features for land-cover classification. The cubic smoothing spline algorithm is used to fit the waveform curve of the received LiDAR signals. After that, the local peak locations of the waveform curve are detected using a second derivative method. According to the detected local peak locations, commonly used full-waveform features such as full width at half maximum (FWHM) and amplitude can then be obtained. In addition, the number of peaks, time difference between the first and last peaks, and the average amplitude are also considered as features of LiDAR waveforms with multiple returns. Based on the waveform geometry, dynamic time-warping (DTW) is applied to measure the waveform similarity. The sum of the absolute amplitude differences that remain after time-warping can be used as a similarity feature in a classification procedure. An airborne full-waveform LiDAR data set was used to test the performance of the developed feature extraction method for land-cover classification. Experimental results indicate that the developed spline curve- fitting algorithm and geometry analysis can extract helpful full-waveform LiDAR features to produce better land-cover classification than conventional LiDAR data and feature extraction methods. In particular, the multiple-return features and the dynamic time-warping index can improve the classification results significantly.

Study of recreational land and open space using Skylab imagery. [Michigan

NASA Technical Reports Server (NTRS)

Sattinger, I. J. (Principal Investigator)

1974-01-01

The author has identified the following significant results. Sl90B color photography has adequate resolution to detect or identify many natural and cultural features which are significant for the evaluation of recreational land and open space. The effectiveness of the interpretation could be improved if coverage were obtained at two or three different seasons so that indicators such as seasonal changes in vegetation cover or snow enhancement could aid the interpretation of land use and land cover. The degree of detail which can be observed from Sl90B photography makes it useful for the following purposes: (1) Photography can be used to obtain general familiarity with a large regional area, and to study interrelationships of major natural and cultural features within the area. (2) Existing recreational facilities such as golf courses, parks, stadiums, race tracks, and marinas can be detected and identified. (3) The photography can be used for initial selection of recreation sites. (4) It would also indicate trends in population growth, which constitute one type of information needed in estimating the growth of recreation demand. The photography has only limited use for planning individual site planning of parks, golf courses, and other recreation facilities.

The ties that bind what is known to the recall of what is new.

PubMed

Nelson, D L; Zhang, N

2000-12-01

Cued recall success varies with what people know and with what they do during an episode. This paper focuses on prior knowledge and disentangles the relative effects of 10 features of words and their relationships on cued recall. Results are reported for correlational and multiple regression analyses of data obtained from free association norms and from 29 experiments. The 10 features were only weakly correlated with each other in the norms and, with notable exceptions, in the experiments. The regression analysis indicated that forward cue-to-target strength explained the most variance, followed by backward target-to-cue strength. Target connectivity and set size explained the next most variance, along with mediated cue-to-target strength. Finally, frequency, concreteness, shared associate strength, and cue set size also contributed significantly to recall. Taken together, indices of prior word knowledge explain 49% of the recall variance. Theoretically driven equations that use free association to predict cued recall were also evaluated. Each equation was designed to condense multiple indices of word interconnectivity into a single predictor.

Data-Science Analysis of the Macro-scale Features Governing the Corrosion to Crack Transition in AA7050-T7451

NASA Astrophysics Data System (ADS)

Co, Noelle Easter C.; Brown, Donald E.; Burns, James T.

2018-05-01

This study applies data science approaches (random forest and logistic regression) to determine the extent to which macro-scale corrosion damage features govern the crack formation behavior in AA7050-T7451. Each corrosion morphology has a set of corresponding predictor variables (pit depth, volume, area, diameter, pit density, total fissure length, surface roughness metrics, etc.) describing the shape of the corrosion damage. The values of the predictor variables are obtained from white light interferometry, x-ray tomography, and scanning electron microscope imaging of the corrosion damage. A permutation test is employed to assess the significance of the logistic and random forest model predictions. Results indicate minimal relationship between the macro-scale corrosion feature predictor variables and fatigue crack initiation. These findings suggest that the macro-scale corrosion features and their interactions do not solely govern the crack formation behavior. While these results do not imply that the macro-features have no impact, they do suggest that additional parameters must be considered to rigorously inform the crack formation location.

Exploiting Acoustic and Syntactic Features for Automatic Prosody Labeling in a Maximum Entropy Framework

PubMed Central

Sridhar, Vivek Kumar Rangarajan; Bangalore, Srinivas; Narayanan, Shrikanth S.

2009-01-01

In this paper, we describe a maximum entropy-based automatic prosody labeling framework that exploits both language and speech information. We apply the proposed framework to both prominence and phrase structure detection within the Tones and Break Indices (ToBI) annotation scheme. Our framework utilizes novel syntactic features in the form of supertags and a quantized acoustic–prosodic feature representation that is similar to linear parameterizations of the prosodic contour. The proposed model is trained discriminatively and is robust in the selection of appropriate features for the task of prosody detection. The proposed maximum entropy acoustic–syntactic model achieves pitch accent and boundary tone detection accuracies of 86.0% and 93.1% on the Boston University Radio News corpus, and, 79.8% and 90.3% on the Boston Directions corpus. The phrase structure detection through prosodic break index labeling provides accuracies of 84% and 87% on the two corpora, respectively. The reported results are significantly better than previously reported results and demonstrate the strength of maximum entropy model in jointly modeling simple lexical, syntactic, and acoustic features for automatic prosody labeling. PMID:19603083

An evaluation of the suitability of ERTS data for the purposes of petroleum exploration

NASA Technical Reports Server (NTRS)

Collins, R. J., Jr. (Principal Investigator); Mccown, F. P.; Stonis, L. P.; Petzel, G.

1973-01-01

The author has identified the following significant results. ERTS-1 imagery seems to be good to excellent for reconnaissance level investigations of large sedimentary basins such as the Anadarko Basin. Many lithologic boundaries, and geomorphic features, and linear features inferred to be indicative of geologic structure are visible in the imagery. This imagery in conjunction with high altitude photography seems to be useful as a tool for intermediate level geologic exploration. Several types of crudely circular anomalous features, such as geomorphic/structural anomalies, hazy areas and tonal anomalies, are identifiable in the imagery. There seems to be a strong correlation between the geomorphic/structural and hazy anomalies and known structurally controlled oil and gas fields. The features recognizable on ERTS-1 imagery and their ease of recognition vary from area to area even in imagery acquired at the same time under essentially uniform atmospheric conditions. Repeated coverage is exceedingly valuable in geologic applications. One time complete coverage even for the various seasons does not reveal all the features that ERTS-1 can reveal.

Rough-Fuzzy Clustering and Unsupervised Feature Selection for Wavelet Based MR Image Segmentation

PubMed Central

Maji, Pradipta; Roy, Shaswati

2015-01-01

Image segmentation is an indispensable process in the visualization of human tissues, particularly during clinical analysis of brain magnetic resonance (MR) images. For many human experts, manual segmentation is a difficult and time consuming task, which makes an automated brain MR image segmentation method desirable. In this regard, this paper presents a new segmentation method for brain MR images, integrating judiciously the merits of rough-fuzzy computing and multiresolution image analysis technique. The proposed method assumes that the major brain tissues, namely, gray matter, white matter, and cerebrospinal fluid from the MR images are considered to have different textural properties. The dyadic wavelet analysis is used to extract the scale-space feature vector for each pixel, while the rough-fuzzy clustering is used to address the uncertainty problem of brain MR image segmentation. An unsupervised feature selection method is introduced, based on maximum relevance-maximum significance criterion, to select relevant and significant textural features for segmentation problem, while the mathematical morphology based skull stripping preprocessing step is proposed to remove the non-cerebral tissues like skull. The performance of the proposed method, along with a comparison with related approaches, is demonstrated on a set of synthetic and real brain MR images using standard validity indices. PMID:25848961

The reliability of continuous brain responses during naturalistic listening to music.

PubMed

Burunat, Iballa; Toiviainen, Petri; Alluri, Vinoo; Bogert, Brigitte; Ristaniemi, Tapani; Sams, Mikko; Brattico, Elvira

2016-01-01

Low-level (timbral) and high-level (tonal and rhythmical) musical features during continuous listening to music, studied by functional magnetic resonance imaging (fMRI), have been shown to elicit large-scale responses in cognitive, motor, and limbic brain networks. Using a similar methodological approach and a similar group of participants, we aimed to study the replicability of previous findings. Participants' fMRI responses during continuous listening of a tango Nuevo piece were correlated voxelwise against the time series of a set of perceptually validated musical features computationally extracted from the music. The replicability of previous results and the present study was assessed by two approaches: (a) correlating the respective activation maps, and (b) computing the overlap of active voxels between datasets at variable levels of ranked significance. Activity elicited by timbral features was better replicable than activity elicited by tonal and rhythmical ones. These results indicate more reliable processing mechanisms for low-level musical features as compared to more high-level features. The processing of such high-level features is probably more sensitive to the state and traits of the listeners, as well as of their background in music. Copyright © 2015 Elsevier Inc. All rights reserved.

Comparison of Different Features and Classifiers for Driver Fatigue Detection Based on a Single EEG Channel

PubMed Central

2017-01-01

Driver fatigue has become an important factor to traffic accidents worldwide, and effective detection of driver fatigue has major significance for public health. The purpose method employs entropy measures for feature extraction from a single electroencephalogram (EEG) channel. Four types of entropies measures, sample entropy (SE), fuzzy entropy (FE), approximate entropy (AE), and spectral entropy (PE), were deployed for the analysis of original EEG signal and compared by ten state-of-the-art classifiers. Results indicate that optimal performance of single channel is achieved using a combination of channel CP4, feature FE, and classifier Random Forest (RF). The highest accuracy can be up to 96.6%, which has been able to meet the needs of real applications. The best combination of channel + features + classifier is subject-specific. In this work, the accuracy of FE as the feature is far greater than the Acc of other features. The accuracy using classifier RF is the best, while that of classifier SVM with linear kernel is the worst. The impact of channel selection on the Acc is larger. The performance of various channels is very different. PMID:28255330

Comparison of Different Features and Classifiers for Driver Fatigue Detection Based on a Single EEG Channel.

PubMed

Hu, Jianfeng

2017-01-01

Driver fatigue has become an important factor to traffic accidents worldwide, and effective detection of driver fatigue has major significance for public health. The purpose method employs entropy measures for feature extraction from a single electroencephalogram (EEG) channel. Four types of entropies measures, sample entropy (SE), fuzzy entropy (FE), approximate entropy (AE), and spectral entropy (PE), were deployed for the analysis of original EEG signal and compared by ten state-of-the-art classifiers. Results indicate that optimal performance of single channel is achieved using a combination of channel CP4, feature FE, and classifier Random Forest (RF). The highest accuracy can be up to 96.6%, which has been able to meet the needs of real applications. The best combination of channel + features + classifier is subject-specific. In this work, the accuracy of FE as the feature is far greater than the Acc of other features. The accuracy using classifier RF is the best, while that of classifier SVM with linear kernel is the worst. The impact of channel selection on the Acc is larger. The performance of various channels is very different.

Long-term memory for temporal structure: evidence form the identification of well-known and novel songs.

PubMed

Schulkind, M D

1999-09-01

In three experiments, long-term memory for temporal structure was examined by having participants identify both well-known (e.g., "I've Been Working on the Railroad") and novel songs. The target songs were subjected to a number of rhythmic alterations, to assess the importance of four critical features of identification performance. The four critical features were meter, phrasing, rhythmic contour (ordinal scaling of note durations), and the ratio of successive durations. In contrast with previous work, the unaltered version of each song was identified significantly better than any altered version. This indicates that rhythm is stored in long-term memory. Furthermore, the results demonstrated that all four critical features play a role in the identification of songs. These results held for both well-known and novel tunes.

Research on driver fatigue detection

NASA Astrophysics Data System (ADS)

Zhang, Ting; Chen, Zhong; Ouyang, Chao

2018-03-01

Driver fatigue is one of the main causes of frequent traffic accidents. In this case, driver fatigue detection system has very important significance in avoiding traffic accidents. This paper presents a real-time method based on fusion of multiple facial features, including eye closure, yawn and head movement. The eye state is classified as being open or closed by a linear SVM classifier trained using HOG features of the detected eye. The mouth state is determined according to the width-height ratio of the mouth. The head movement is detected by head pitch angle calculated by facial landmark. The driver's fatigue state can be reasoned by the model trained by above features. According to experimental results, drive fatigue detection obtains an excellent performance. It indicates that the developed method is valuable for the application of avoiding traffic accidents caused by driver's fatigue.

Silicate Emission in the TW Hydrae Association

NASA Astrophysics Data System (ADS)

Sitko, Michael L.; Lynch, David K.; Russell, Ray W.

2000-11-01

The TW Hydrae association is the nearest young stellar association. Among its members are HD 98800, HR 4796A, and TW Hydrae itself, the nearest known classical T Tauri star. We have observed these three stars spectroscopically between 3 and 13 μm. In TW Hya, the spectrum shows a silicate emission feature that is similar to many other young stars' with protostellar disks. The 11.2 μm feature indicative of significant amounts of crystalline olivine is not as strong as in some young stars and solar system comets. In HR 4796A, the thermal emission in the silicate feature is very weak, suggesting little in the way of (small silicate) grains near the star. The silicate band of HD 98800 (observed by us, but also reported by Sylvester & Skinner) is intermediate in strength between TW Hya and HR 4796A.

A Machine Learning Approach to Discover Rules for Expressive Performance Actions in Jazz Guitar Music.

PubMed

Giraldo, Sergio I; Ramirez, Rafael

2016-01-01

Expert musicians introduce expression in their performances by manipulating sound properties such as timing, energy, pitch, and timbre. Here, we present a data driven computational approach to induce expressive performance rule models for note duration, onset, energy, and ornamentation transformations in jazz guitar music. We extract high-level features from a set of 16 commercial audio recordings (and corresponding music scores) of jazz guitarist Grant Green in order to characterize the expression in the pieces. We apply machine learning techniques to the resulting features to learn expressive performance rule models. We (1) quantitatively evaluate the accuracy of the induced models, (2) analyse the relative importance of the considered musical features, (3) discuss some of the learnt expressive performance rules in the context of previous work, and (4) assess their generailty. The accuracies of the induced predictive models is significantly above base-line levels indicating that the audio performances and the musical features extracted contain sufficient information to automatically learn informative expressive performance patterns. Feature analysis shows that the most important musical features for predicting expressive transformations are note duration, pitch, metrical strength, phrase position, Narmour structure, and tempo and key of the piece. Similarities and differences between the induced expressive rules and the rules reported in the literature were found. Differences may be due to the fact that most previously studied performance data has consisted of classical music recordings. Finally, the rules' performer specificity/generality is assessed by applying the induced rules to performances of the same pieces performed by two other professional jazz guitar players. Results show a consistency in the ornamentation patterns between Grant Green and the other two musicians, which may be interpreted as a good indicator for generality of the ornamentation rules.

Very high resolution Earth observation features for monitoring plant and animal community structure across multiple spatial scales in protected areas

NASA Astrophysics Data System (ADS)

Mairota, Paola; Cafarelli, Barbara; Labadessa, Rocco; Lovergine, Francesco; Tarantino, Cristina; Lucas, Richard M.; Nagendra, Harini; Didham, Raphael K.

2015-05-01

Monitoring the status and future trends in biodiversity can be prohibitively expensive using ground-based surveys. Consequently, significant effort is being invested in the use of satellite remote sensing to represent aspects of the proximate mechanisms (e.g., resource availability) that can be related to biodiversity surrogates (BS) such as species community descriptors. We explored the potential of very high resolution (VHR) satellite Earth observation (EO) features as proxies for habitat structural attributes that influence spatial variation in habitat quality and biodiversity change. In a semi-natural grassland mosaic of conservation concern in southern Italy, we employed a hierarchical nested sampling strategy to collect field and VHR-EO data across three spatial extent levels (landscape, patch and plot). Species incidence and abundance data were collected at the plot level for plant, insect and bird functional groups. Spectral and textural VHR-EO image features were derived from a Worldview-2 image. Three window sizes (grains) were tested for analysis and computation of textural features, guided by the perception limits of different organisms. The modelled relationships between VHR-EO features and BS responses differed across scales, suggesting that landscape, patch and plot levels are respectively most appropriate when dealing with birds, plants and insects. This research demonstrates the potential of VHR-EO for biodiversity mapping and habitat modelling, and highlights the importance of identifying the appropriate scale of analysis for specific taxonomic groups of interest. Further, textural features are important in the modelling of functional group-specific indices which represent BS in high conservation value habitat types, and provide a more direct link to species interaction networks and ecosystem functioning, than provided by traditional taxonomic diversity indices.

A Machine Learning Approach to Discover Rules for Expressive Performance Actions in Jazz Guitar Music

PubMed Central

Giraldo, Sergio I.; Ramirez, Rafael

2016-01-01

Expert musicians introduce expression in their performances by manipulating sound properties such as timing, energy, pitch, and timbre. Here, we present a data driven computational approach to induce expressive performance rule models for note duration, onset, energy, and ornamentation transformations in jazz guitar music. We extract high-level features from a set of 16 commercial audio recordings (and corresponding music scores) of jazz guitarist Grant Green in order to characterize the expression in the pieces. We apply machine learning techniques to the resulting features to learn expressive performance rule models. We (1) quantitatively evaluate the accuracy of the induced models, (2) analyse the relative importance of the considered musical features, (3) discuss some of the learnt expressive performance rules in the context of previous work, and (4) assess their generailty. The accuracies of the induced predictive models is significantly above base-line levels indicating that the audio performances and the musical features extracted contain sufficient information to automatically learn informative expressive performance patterns. Feature analysis shows that the most important musical features for predicting expressive transformations are note duration, pitch, metrical strength, phrase position, Narmour structure, and tempo and key of the piece. Similarities and differences between the induced expressive rules and the rules reported in the literature were found. Differences may be due to the fact that most previously studied performance data has consisted of classical music recordings. Finally, the rules' performer specificity/generality is assessed by applying the induced rules to performances of the same pieces performed by two other professional jazz guitar players. Results show a consistency in the ornamentation patterns between Grant Green and the other two musicians, which may be interpreted as a good indicator for generality of the ornamentation rules. PMID:28066290

A new method for enhancer prediction based on deep belief network.

PubMed

Bu, Hongda; Gan, Yanglan; Wang, Yang; Zhou, Shuigeng; Guan, Jihong

2017-10-16

Studies have shown that enhancers are significant regulatory elements to play crucial roles in gene expression regulation. Since enhancers are unrelated to the orientation and distance to their target genes, it is a challenging mission for scholars and researchers to accurately predicting distal enhancers. In the past years, with the high-throughout ChiP-seq technologies development, several computational techniques emerge to predict enhancers using epigenetic or genomic features. Nevertheless, the inconsistency of computational models across different cell-lines and the unsatisfactory prediction performance call for further research in this area. Here, we propose a new Deep Belief Network (DBN) based computational method for enhancer prediction, which is called EnhancerDBN. This method combines diverse features, composed of DNA sequence compositional features, DNA methylation and histone modifications. Our computational results indicate that 1) EnhancerDBN outperforms 13 existing methods in prediction, and 2) GC content and DNA methylation can serve as relevant features for enhancer prediction. Deep learning is effective in boosting the performance of enhancer prediction.

A malware detection scheme based on mining format information.

PubMed

Bai, Jinrong; Wang, Junfeng; Zou, Guozhong

2014-01-01

Malware has become one of the most serious threats to computer information system and the current malware detection technology still has very significant limitations. In this paper, we proposed a malware detection approach by mining format information of PE (portable executable) files. Based on in-depth analysis of the static format information of the PE files, we extracted 197 features from format information of PE files and applied feature selection methods to reduce the dimensionality of the features and achieve acceptable high performance. When the selected features were trained using classification algorithms, the results of our experiments indicate that the accuracy of the top classification algorithm is 99.1% and the value of the AUC is 0.998. We designed three experiments to evaluate the performance of our detection scheme and the ability of detecting unknown and new malware. Although the experimental results of identifying new malware are not perfect, our method is still able to identify 97.6% of new malware with 1.3% false positive rates.

A Malware Detection Scheme Based on Mining Format Information

PubMed Central

Bai, Jinrong; Wang, Junfeng; Zou, Guozhong

2014-01-01

Malware has become one of the most serious threats to computer information system and the current malware detection technology still has very significant limitations. In this paper, we proposed a malware detection approach by mining format information of PE (portable executable) files. Based on in-depth analysis of the static format information of the PE files, we extracted 197 features from format information of PE files and applied feature selection methods to reduce the dimensionality of the features and achieve acceptable high performance. When the selected features were trained using classification algorithms, the results of our experiments indicate that the accuracy of the top classification algorithm is 99.1% and the value of the AUC is 0.998. We designed three experiments to evaluate the performance of our detection scheme and the ability of detecting unknown and new malware. Although the experimental results of identifying new malware are not perfect, our method is still able to identify 97.6% of new malware with 1.3% false positive rates. PMID:24991639

A Multifeatures Fusion and Discrete Firefly Optimization Method for Prediction of Protein Tyrosine Sulfation Residues.

PubMed

Guo, Song; Liu, Chunhua; Zhou, Peng; Li, Yanling

2016-01-01

Tyrosine sulfation is one of the ubiquitous protein posttranslational modifications, where some sulfate groups are added to the tyrosine residues. It plays significant roles in various physiological processes in eukaryotic cells. To explore the molecular mechanism of tyrosine sulfation, one of the prerequisites is to correctly identify possible protein tyrosine sulfation residues. In this paper, a novel method was presented to predict protein tyrosine sulfation residues from primary sequences. By means of informative feature construction and elaborate feature selection and parameter optimization scheme, the proposed predictor achieved promising results and outperformed many other state-of-the-art predictors. Using the optimal features subset, the proposed method achieved mean MCC of 94.41% on the benchmark dataset, and a MCC of 90.09% on the independent dataset. The experimental performance indicated that our new proposed method could be effective in identifying the important protein posttranslational modifications and the feature selection scheme would be powerful in protein functional residues prediction research fields.

A Multifeatures Fusion and Discrete Firefly Optimization Method for Prediction of Protein Tyrosine Sulfation Residues

PubMed Central

Liu, Chunhua; Zhou, Peng; Li, Yanling

2016-01-01

Tyrosine sulfation is one of the ubiquitous protein posttranslational modifications, where some sulfate groups are added to the tyrosine residues. It plays significant roles in various physiological processes in eukaryotic cells. To explore the molecular mechanism of tyrosine sulfation, one of the prerequisites is to correctly identify possible protein tyrosine sulfation residues. In this paper, a novel method was presented to predict protein tyrosine sulfation residues from primary sequences. By means of informative feature construction and elaborate feature selection and parameter optimization scheme, the proposed predictor achieved promising results and outperformed many other state-of-the-art predictors. Using the optimal features subset, the proposed method achieved mean MCC of 94.41% on the benchmark dataset, and a MCC of 90.09% on the independent dataset. The experimental performance indicated that our new proposed method could be effective in identifying the important protein posttranslational modifications and the feature selection scheme would be powerful in protein functional residues prediction research fields. PMID:27034949

Study of morphological and mechanical features of multinuclear and mononuclear SW480 cells by atomic force microscopy.

PubMed

Liu, Jinyun; Qu, Yingmin; Wang, Guoliang; Wang, Xinyue; Zhang, Wenxiao; Li, Jingmei; Wang, Zuobin; Li, Dayou; Jiang, Jinlan

2018-01-01

This article studies the morphological and mechanical features of multinuclear and mononuclear SW480 colon cancer cells by atomic force microscopy to understand their drug-resistance. The SW480 cells were incubated with the fullerenol concentrations of 1 mg/ml and 2 mg/ml. Morphological and mechanical features including the height, length, width, roughness, adhesion force and Young's modulus of three multinuclear cell groups and three mononuclear cell groups were imaged and analyzed. It was observed that the features of multinuclear cancer cells and mononuclear cancer cells were significantly different after the treatment with fullerenol. The experiment results indicated that the mononuclear SW480 cells were more sensitive to fullerenol than the multinuclear SW480 cells, and the multinuclear SW480 cells exhibited a stronger drug-resistance than the mononuclear SW480 cells. This work provides a guideline for the treatments of multinuclear and mononuclear cancer cells with drugs. © 2017 Wiley Periodicals, Inc.

Subtyping depression by clinical features: the Australasian database.

PubMed

Parker, G; Roy, K; Hadzi-Pavlovic, D; Mitchell, P; Wilhelm, K; Menkes, D B; Snowdon, J; Loo, C; Schweitzer, I

2000-01-01

To distinguish psychotic, melancholic and a residual non-melancholic class on the basis of clinical features alone. Previous studies at our Mood Disorders Unit (MDU) favour a hierarchical model, with the classes able to be distinguished by two specific clinical features, but any such intramural study risks rater bias and requires external replication. This replication study involved 27 Australasian psychiatrist raters, thus extending the sample and raters beyond the MDU facility. They collected clinical feature data using a standardized assessment with precoded rating options. A psychotic depression (PD) class was derived by respecting DSM-IV decision rules while a cluster analysis distinguished melancholic (MEL) and non-melancholic classes. The MELs were distinguished virtually entirely by the presence of significant psychomotor disturbance (PMD), as rated by the observationally based CORE measure, with over-representation on only three of an extensive set of 'endogeneity symptoms'. In comparison to PMD, endogeneity symptoms appear to be poor indicators of 'melancholic' type, confounding typology with severity. Results again support the hierarchical model.

New insights into the biology and origin of mature aggressive B-cell lymphomas by combined epigenomic, genomic, and transcriptional profiling.

PubMed

Martín-Subero, José I; Kreuz, Markus; Bibikova, Marina; Bentink, Stefan; Ammerpohl, Ole; Wickham-Garcia, Eliza; Rosolowski, Maciej; Richter, Julia; Lopez-Serra, Lidia; Ballestar, Esteban; Berger, Hilmar; Agirre, Xabier; Bernd, Heinz-Wolfram; Calvanese, Vincenzo; Cogliatti, Sergio B; Drexler, Hans G; Fan, Jian-Bing; Fraga, Mario F; Hansmann, Martin L; Hummel, Michael; Klapper, Wolfram; Korn, Bernhard; Küppers, Ralf; Macleod, Roderick A F; Möller, Peter; Ott, German; Pott, Christiane; Prosper, Felipe; Rosenwald, Andreas; Schwaenen, Carsten; Schübeler, Dirk; Seifert, Marc; Stürzenhofecker, Benjamin; Weber, Michael; Wessendorf, Swen; Loeffler, Markus; Trümper, Lorenz; Stein, Harald; Spang, Rainer; Esteller, Manel; Barker, David; Hasenclever, Dirk; Siebert, Reiner

2009-03-12

Lymphomas are assumed to originate at different stages of lymphocyte development through chromosomal aberrations. Thus, different lymphomas resemble lymphocytes at distinct differentiation stages and show characteristic morphologic, genetic, and transcriptional features. Here, we have performed a microarray-based DNA methylation profiling of 83 mature aggressive B-cell non-Hodgkin lymphomas (maB-NHLs) characterized for their morphologic, genetic, and transcriptional features, including molecular Burkitt lymphomas and diffuse large B-cell lymphomas. Hierarchic clustering indicated that methylation patterns in maB-NHLs were not strictly associated with morphologic, genetic, or transcriptional features. By supervised analyses, we identified 56 genes de novo methylated in all lymphoma subtypes studied and 22 methylated in a lymphoma subtype-specific manner. Remarkably, the group of genes de novo methylated in all lymphoma subtypes was significantly enriched for polycomb targets in embryonic stem cells. De novo methylated genes in all maB-NHLs studied were expressed at low levels in lymphomas and normal hematopoietic tissues but not in nonhematopoietic tissues. These findings, especially the enrichment for polycomb targets in stem cells, indicate that maB-NHLs with different morphologic, genetic, and transcriptional background share a similar stem cell-like epigenetic pattern. This suggests that maB-NHLs originate from cells with stem cell features or that stemness was acquired during lymphomagenesis by epigenetic remodeling.

Personal recognition using hand shape and texture.

PubMed

Kumar, Ajay; Zhang, David

2006-08-01

This paper proposes a new bimodal biometric system using feature-level fusion of hand shape and palm texture. The proposed combination is of significance since both the palmprint and hand-shape images are proposed to be extracted from the single hand image acquired from a digital camera. Several new hand-shape features that can be used to represent the hand shape and improve the performance are investigated. The new approach for palmprint recognition using discrete cosine transform coefficients, which can be directly obtained from the camera hardware, is demonstrated. None of the prior work on hand-shape or palmprint recognition has given any attention on the critical issue of feature selection. Our experimental results demonstrate that while majority of palmprint or hand-shape features are useful in predicting the subjects identity, only a small subset of these features are necessary in practice for building an accurate model for identification. The comparison and combination of proposed features is evaluated on the diverse classification schemes; naive Bayes (normal, estimated, multinomial), decision trees (C4.5, LMT), k-NN, SVM, and FFN. Although more work remains to be done, our results to date indicate that the combination of selected hand-shape and palmprint features constitutes a promising addition to the biometrics-based personal recognition systems.

Humor drawings evoked temporal and spectral EEG processes

PubMed Central

Kuo, Hsien-Chu; Chuang, Shang-Wen

2017-01-01

Abstract The study aimed to explore the humor processing elicited through the manipulation of artistic drawings. Using the Comprehension–Elaboration Theory of humor as the main research background, the experiment manipulated the head portraits of celebrities based on the independent variables of facial deformation (large/small) and addition of affective features (positive/negative). A 64-channel electroencephalography was recorded in 30 participants while viewing the incongruous drawings of celebrities. The electroencephalography temporal and spectral responses were measured during the three stages of humor which included incongruity detection, incongruity comprehension and elaboration of humor. Analysis of event-related potentials indicated that for humorous vs non-humorous drawings, facial deformation and the addition of affective features significantly affected the degree of humor elicited, specifically: large > small deformation; negative > positive affective features. The N170, N270, N400, N600-800 and N900-1200 components showed significant differences, particularly in the right prefrontal and frontal regions. Analysis of event-related spectral perturbation showed significant differences in the theta band evoked in the anterior cingulate cortex, parietal region and posterior cingulate cortex; and in the alpha and beta bands in the motor areas. These regions are involved in emotional processing, memory retrieval, and laughter and feelings of amusement induced by elaboration of the situation. PMID:28402573

Application of Fuzzy c-Means and Joint-Feature-Clustering to Detect Redundancies of Image-Features in Drug Combinations Studies of Breast Cancer

NASA Astrophysics Data System (ADS)

Brandl, Miriam B.; Beck, Dominik; Pham, Tuan D.

2011-06-01

The high dimensionality of image-based dataset can be a drawback for classification accuracy. In this study, we propose the application of fuzzy c-means clustering, cluster validity indices and the notation of a joint-feature-clustering matrix to find redundancies of image-features. The introduced matrix indicates how frequently features are grouped in a mutual cluster. The resulting information can be used to find data-derived feature prototypes with a common biological meaning, reduce data storage as well as computation times and improve the classification accuracy.

Indicators of walking speed in rheumatoid arthritis: relative influence of articular, psychosocial, and body composition characteristics.

PubMed

Lusa, Amanda L; Amigues, Isabelle; Kramer, Henry R; Dam, Thuy-Tien; Giles, Jon T

2015-01-01

To explore the contributions from and interactions between articular swelling and damage, psychosocial factors, and body composition characteristics on walking speed in rheumatoid arthritis (RA). RA patients underwent the timed 400-meter long-corridor walk. Demographics, self-reported levels of depressive symptoms and fatigue, RA characteristics, and body composition (using whole-body dual X-ray absorptiometry, and abdominal and thigh computed tomography) were assessed and their associations with walking speed explored. A total of 132 RA patients had data for the 400-meter walk, among whom 107 (81%) completed the full 400 meters. Significant multivariable indicators of slower walking speed were older age, higher depression scores, higher reported pain and fatigue, higher swollen and replaced joint counts, higher cumulative prednisone exposure, nontreatment with disease-modifying antirheumatic drugs, and worse body composition. These features accounted for 60% of the modeled variability in walking speed. Among specific articular features, slower walking speed was primarily correlated with large/medium lower-extremity joint involvement. However, these articular features accounted for only 21% of the explainable variability in walking speed. Having any relevant articular characteristic was associated with a 20% lower walking speed among those with worse body composition (P < 0.001), compared with only a 6% lower speed among those with better body composition (P = 0.010 for interaction). Psychosocial factors and body composition are potentially reversible contributors to walking speed in RA. Relative to articular disease activity and damage, nonarticular indicators were collectively more potent indicators of an individual's mobility limitations. Copyright © 2015 by the American College of Rheumatology.

CT texture features of liver parenchyma for predicting development of metastatic disease and overall survival in patients with colorectal cancer.

PubMed

Lee, Scott J; Zea, Ryan; Kim, David H; Lubner, Meghan G; Deming, Dustin A; Pickhardt, Perry J

2018-04-01

To determine if identifiable hepatic textural features are present at abdominal CT in patients with colorectal cancer (CRC) prior to the development of CT-detectable hepatic metastases. Four filtration-histogram texture features (standard deviation, skewness, entropy and kurtosis) were extracted from the liver parenchyma on portal venous phase CT images at staging and post-treatment surveillance. Surveillance scans corresponded to the last scan prior to the development of CT-detectable CRC liver metastases in 29 patients (median time interval, 6 months), and these were compared with interval-matched surveillance scans in 60 CRC patients who did not develop liver metastases. Predictive models of liver metastasis-free survival and overall survival were built using regularised Cox proportional hazards regression. Texture features did not significantly differ between cases and controls. For Cox models using all features as predictors, all coefficients were shrunk to zero, suggesting no association between any CT texture features and outcomes. Prognostic indices derived from entropy features at surveillance CT incorrectly classified patients into risk groups for future liver metastases (p < 0.001). On surveillance CT scans immediately prior to the development of CRC liver metastases, we found no evidence suggesting that changes in identifiable hepatic texture features were predictive of their development. • No correlation between liver texture features and metastasis-free survival was observed. • Liver texture features incorrectly classified patients into risk groups for liver metastases. • Standardised texture analysis workflows need to be developed to improve research reproducibility.

Application of infrared thermal imaging in the study of preventing cardiovascular and cerebrovascular diseases with Chinese medicine health food

NASA Astrophysics Data System (ADS)

Li, Ziru; Zhang, Xusheng

2009-08-01

To explore the assessing technique which could objectively reflect the characteristics of Chinese medicine in the prevention of cardiovascular and cerebrovascular diseases, four balance features of infrared thermal images (ITI) corresponding to the up and down, left and right, proximal and distal balance of blood circulation of human body were studied. First, the ITI features of the middle-aged and elderly people with lipid abnormality history were compared with those of the healthy youth. It was found that the balance state of the youth was significantly better than that of the middle-aged and elderly, P<=0.01 for all the balance features. For the youth, the balance state of females was better than that of the males. But this sexual difference disappeared for the middle-aged and elderly group. Second, a double-blind randomized trial was carried out to study the influences of Shengyi capsule, a Chinese medicine health food with the function of helping to decrease serum lipid, on the balance features. The subjects were middle-aged and elderly people with lipid abnormality history. Shengyi capsule was taken by the trial group while Xuezhikang capsule (with lovastatin as the main effective component) by the control group for 108 days. The balance features of ITI showed that Shengyi was significantly better than Xuezhikang in improving the whole body balance of blood circulation (including the up and down, left and right, proximal and distal balance). The relative efficacy rate was 81.0% for the trial group and 33.3% for the control group, there was significant difference between the two groups (P=0.002). Shengyi could effectively decrease the low density lipoprotein cholesterol (LDL-C) but the effect of Xuezhikang in decreasing total cholesterol (TC) and LDL-C was better than Shengyi. Though the lipid-lowering effect of Shengyi was not as good as Xuezhikang, ITI reflected the obvious advantage of Shengyi in improving the whole body balance of blood circulation which indicated that helping to decrease serum lipid is only part of the health function of Shengyi. The physiology and pathology basis of the influences of Shengyi on the four balance features and its relationship with the clinical outcome deserves further study. So the prospect of infrared thermal imaging is indicated as the suitable evaluation technique which could objectively reflect the whole balance regulation advantage of Chinese medicinal compounds.

Deriving leaf mass per area (LMA) from foliar reflectance across a variety of plant species using continuous wavelet analysis

NASA Astrophysics Data System (ADS)

Cheng, Tao; Rivard, Benoit; Sánchez-Azofeifa, Arturo G.; Féret, Jean-Baptiste; Jacquemoud, Stéphane; Ustin, Susan L.

2014-01-01

Leaf mass per area (LMA), the ratio of leaf dry mass to leaf area, is a trait of central importance to the understanding of plant light capture and carbon gain. It can be estimated from leaf reflectance spectroscopy in the infrared region, by making use of information about the absorption features of dry matter. This study reports on the application of continuous wavelet analysis (CWA) to the estimation of LMA across a wide range of plant species. We compiled a large database of leaf reflectance spectra acquired within the framework of three independent measurement campaigns (ANGERS, LOPEX and PANAMA) and generated a simulated database using the PROSPECT leaf optical properties model. CWA was applied to the measured and simulated databases to extract wavelet features that correlate with LMA. These features were assessed in terms of predictive capability and robustness while transferring predictive models from the simulated database to the measured database. The assessment was also conducted with two existing spectral indices, namely the Normalized Dry Matter Index (NDMI) and the Normalized Difference index for LMA (NDLMA). Five common wavelet features were determined from the two databases, which showed significant correlations with LMA (R2: 0.51-0.82, p < 0.0001). The best robustness (R2 = 0.74, RMSE = 18.97 g/m2 and Bias = 0.12 g/m2) was obtained using a combination of two low-scale features (1639 nm, scale 4) and (2133 nm, scale 5), the first being predominantly important. The transferability of the wavelet-based predictive model to the whole measured database was either better than or comparable to those based on spectral indices. Additionally, only the wavelet-based model showed consistent predictive capabilities among the three measured data sets. In comparison, the models based on spectral indices were sensitive to site-specific data sets. Integrating the NDLMA spectral index and the two robust wavelet features improved the LMA prediction. One of the bands used by this spectral index, 1368 nm, was located in a strong atmospheric water absorption region and replacing it with the next available band (1340 nm) led to lower predictive accuracies. However, the two wavelet features were not affected by data quality in the atmospheric absorption regions and therefore showed potential for canopy-level investigations. The wavelet approach provides a different perspective into spectral responses to LMA variation than the traditional spectral indices and holds greater promise for implementation with airborne or spaceborne imaging spectroscopy data for mapping canopy foliar dry biomass.

Visual imagery processing and knowledge of famous names in Alzheimer's disease and MCI.

PubMed

Borg, Céline; Thomas-Antérion, Catherine; Bogey, Soline; Davier, Karine; Laurent, Bernard

2010-09-01

The study of memory for famous people and visual imagery retrieval was investigated in patients in the early stages of Alzheimer's disease (AD) and in the prodromal stage of AD, so-called Mild Cognitive Impairment (MCI). Fifteen patients with AD (MMSE > or = 23), 15 patients with amnestic MCI (a-MCI) and 15 normal controls (NC) performed a famous names test designed to evaluate the semantic and distinctive physical features knowledge of famous persons. Results indicated that patients with AD and a-MCI generated significantly less physical features and semantic biographical knowledge about famous persons than did normal control participants. Additionally, significant differences were observed between a-MCI and AD patients in all tasks. The present findings confirm recent studies reporting semantic memory impairment in MCI. Moreover, the current findings show that mental imagery is lowered in a-MCI and AD and is likely related to the early semantic impairment.

Late Holocene liquefaction features in the Dominican Republic: A powerful tool for earthquake hazard assessment in the northeastern Caribbean

USGS Publications Warehouse

Tuttle, M.P.; Prentice, C.S.; Dyer-Williams, K.; Pena, L.R.; Burr, G.

2003-01-01

Several generations of sand blows and sand dikes, indicative of significant and recurrent liquefaction, are preserved in the late Holocene alluvial deposits of the Cibao Valley in northern Dominican Republic. The Cibao Valley is structurally controlled by the Septentrional fault, an onshore section of the North American-Caribbean strike-slip plate boundary. The Septentrional fault was previously studied in the central part of the valley, where it sinistrally offsets Holocene terrace risers and soil horizons. In the eastern and western parts of the valley, the Septentrional fault is buried by Holocene alluvial deposits, making direct study of the structure difficult. Liquefaction features that formed in these Holocene deposits as a result of strong ground shaking provide a record of earthquakes in these areas. Liquefaction features in the eastern Cibao Valley indicate that at least one historic earthquake, probably the moment magnitude, M 8, 4 August 1946 event, and two to four prehistoric earthquakes of M 7 to 8 struck this area during the past 1100 yr. The prehistoric earthquakes appear to cluster in time and could have resulted from rupture of the central and eastern sections of the Septentrional fault circa A.D. 1200. Liquefaction features in the western Cibao Valley indicate that one historic earthquake, probably the M 8, 7 May 1842 event, and two prehistoric earthquakes of M 7-8 struck this area during the past 1600 yr. Our findings suggest that rupture of the Septentrional fault circa A.D. 1200 may have extended beyond the central Cibao Valley and generated an earthquake of M 8. Additional information regarding the age and size distribution of liquefaction features is needed to reconstruct the prehistoric earthquake history of Hispaniola and to define the long-term behavior and earthquake potential of faults associated with the North American-Caribbean plate boundary.

Predict drug permeability to blood–brain-barrier from clinical phenotypes: drug side effects and drug indications

PubMed Central

Gao, Zhen; Chen, Yang; Cai, Xiaoshu; Xu, Rong

2017-01-01

Abstract Motivation: Blood–Brain-Barrier (BBB) is a rigorous permeability barrier for maintaining homeostasis of Central Nervous System (CNS). Determination of compound’s permeability to BBB is prerequisite in CNS drug discovery. Existing computational methods usually predict drug BBB permeability from chemical structure and they generally apply to small compounds passing BBB through passive diffusion. As abundant information on drug side effects and indications has been recorded over time through extensive clinical usage, we aim to explore BBB permeability prediction from a new angle and introduce a novel approach to predict BBB permeability from drug clinical phenotypes (drug side effects and drug indications). This method can apply to both small compounds and macro-molecules penetrating BBB through various mechanisms besides passive diffusion. Results: We composed a training dataset of 213 drugs with known brain and blood steady-state concentrations ratio and extracted their side effects and indications as features. Next, we trained SVM models with polynomial kernel and obtained accuracy of 76.0%, AUC 0.739, and F1 score (macro weighted) 0.760 with Monte Carlo cross validation. The independent test accuracy was 68.3%, AUC 0.692, F1 score 0.676. When both chemical features and clinical phenotypes were available, combining the two types of features achieved significantly better performance than chemical feature based approach (accuracy 85.5% versus 72.9%, AUC 0.854 versus 0.733, F1 score 0.854 versus 0.725; P < e−90). We also conducted de novo prediction and identified 110 drugs in SIDER database having the potential to penetrate BBB, which could serve as start point for CNS drug repositioning research. Availability and Implementation: https://github.com/bioinformatics-gao/CASE-BBB-prediction-Data Contact: rxx@case.edu Supplementary information: Supplementary data are available at Bioinformatics online. PMID:27993785

Clinicopathological features and clinical outcomes associated with TP53 and BRAFNon-V600 mutations in cutaneous melanoma patients.

PubMed

Kim, Dae Won; Haydu, Lauren E; Joon, Aron Y; Bassett, Roland L; Siroy, Alan E; Tetzlaff, Michael T; Routbort, Mark J; Amaria, Rodabe N; Wargo, Jennifer A; McQuade, Jennifer L; Kemnade, Jan; Hwu, Patrick; Woodman, Scott E; Roszik, Jason; Kim, Kevin B; Gershenwald, Jeffrey E; Lazar, Alexander J; Davies, Michael A

2017-04-15

BRAF V600 , NRAS, TP53, and BRAF Non-V600 are among the most common mutations detected in non-acral cutaneous melanoma patients. Although several studies have identified clinical and pathological features associated with BRAF V600 and NRAS mutations, limited data are available regarding the correlates and significance of TP53 and BRAF Non-V600 mutations. This study analyzed the patient demographics, primary tumor features, and clinical outcomes of a large cohort of non-acral cutaneous melanoma patients who had undergone clinically indicated molecular testing (n = 926). The prevalence of BRAF V600 , NRAS, TP53, and BRAF Non-V600 mutations was 43%, 21%, 19%, and 7%, respectively. The presence of a TP53 mutation was associated with older age (P = .019), a head and neck primary tumor site (P = .0001), and longer overall survival (OS) from the diagnosis of stage IV disease in univariate (P = .039) and multivariate analyses (P = .015). BRAF Non-V600 mutations were associated with older age (P = .005) but not with primary tumor features or OS from stage IV. Neither TP53 nor BRAF Non-V600 mutations correlated significantly with OS with frontline ipilimumab treatment, and the TP53 status was not significantly associated with outcomes with frontline BRAF inhibitor therapy. Eleven patients with BRAF Non-V600 mutations were treated with a BRAF inhibitor. Three patients were not evaluable for a response because of treatment cessation for toxicities; the remaining patients had disease progression as the best response to therapy. These results add to the understanding of the clinical features associated with TP53 and BRAF Non-V600 mutations in advanced cutaneous melanoma patients, and they support the rationale for evaluating the prognostic significance of TP53 in other cohorts of melanoma patients. Cancer 2017;123:1372-1381. © 2016 American Cancer Society. © 2016 American Cancer Society.

New breast cancer prognostic factors identified by computer-aided image analysis of HE stained histopathology images

PubMed Central

Chen, Jia-Mei; Qu, Ai-Ping; Wang, Lin-Wei; Yuan, Jing-Ping; Yang, Fang; Xiang, Qing-Ming; Maskey, Ninu; Yang, Gui-Fang; Liu, Juan; Li, Yan

2015-01-01

Computer-aided image analysis (CAI) can help objectively quantify morphologic features of hematoxylin-eosin (HE) histopathology images and provide potentially useful prognostic information on breast cancer. We performed a CAI workflow on 1,150 HE images from 230 patients with invasive ductal carcinoma (IDC) of the breast. We used a pixel-wise support vector machine classifier for tumor nests (TNs)-stroma segmentation, and a marker-controlled watershed algorithm for nuclei segmentation. 730 morphologic parameters were extracted after segmentation, and 12 parameters identified by Kaplan-Meier analysis were significantly associated with 8-year disease free survival (P < 0.05 for all). Moreover, four image features including TNs feature (HR 1.327, 95%CI [1.001 - 1.759], P = 0.049), TNs cell nuclei feature (HR 0.729, 95%CI [0.537 - 0.989], P = 0.042), TNs cell density (HR 1.625, 95%CI [1.177 - 2.244], P = 0.003), and stromal cell structure feature (HR 1.596, 95%CI [1.142 - 2.229], P = 0.006) were identified by multivariate Cox proportional hazards model to be new independent prognostic factors. The results indicated that CAI can assist the pathologist in extracting prognostic information from HE histopathology images for IDC. The TNs feature, TNs cell nuclei feature, TNs cell density, and stromal cell structure feature could be new prognostic factors. PMID:26022540

Permafrost features on Earth and Mars: Similarities, differences

NASA Technical Reports Server (NTRS)

Joens, H. P.

1985-01-01

Typical permafrost features on Earth are polygonal structures, pingos and soli-/gelifluxion features. In areas around the poles and in mountain ranges the precipitation accumulates to inland ice or ice streams. On Mars the same features were identified: polygonal features cover the larger part of the northern lowlands indicating probably an ice wedge-/sand wedge system or desiccation cracks. These features indicate the extend of large mud accumulations which seem to be related to large outflow events of the chaotic terrains. The shore line of this mud accumulation is indicated by a special set of relief types. In some areas large pingo-like hills were identified. In the vicinity of the largest martian volcano, Olympus Mons, the melting of underlying permafrost and/or ground ice led to the downslope sliding of large parts of the primary shield which formed the aureole around Olympus Mons. Glacier-like features are identified along the escarpment which separates the Southern Uplands from the Northern Lowlands.

Multisite accelerometry for sleep and wake classification in children.

PubMed

Lamprecht, Marnie L; Bradley, Andrew P; Tran, Tommy; Boynton, Alison; Terrill, Philip I

2015-01-01

Actigraphy is a useful alternative to the gold standard polysomnogram for non-invasively measuring sleep and wakefulness. However, it is unable to accurately assess sleep fragmentation due to its inability to differentiate restless sleep from wakefulness and quiet wake from sleep. This presents significant limitations in the assessment of sleep-related breathing disorders where sleep fragmentation is a common symptom. We propose that this limitation may be caused by hardware constraints and movement representation techniques. Our objective was to determine if multisite tri-axial accelerometry improves sleep and wake classification. Twenty-four patients aged 6-15 years (median: 8 years, 16 male) underwent a diagnostic polysomnogram while simultaneously recording motion from the left wrist and index fingertip, upper thorax and left ankle and great toe using a custom accelerometry system. Movement was quantified using several features and two feature selection techniques were employed to select optimal features for restricted feature set sizes. A heuristic was also applied to identify movements during restless sleep. The sleep and wake classification performance was then assessed and validated against the manually scored polysomnogram using discriminant analysis. Tri-axial accelerometry measured at the wrist significantly improved the wake detection when compared to uni-axial accelerometry (specificity at 85% sensitivity: 71.3(14.2)% versus 55.2(24.7)%, p < 0.01). Multisite accelerometry significantly improved the performance when compared to the single wrist placement (specificity at 85% sensitivity: 82.1(12.5)% versus 71.3(14.2)%, p < 0.05). Our results indicate that multisite accelerometry offers a significant performance benefit which could be further improved by analysing movement in raw multisite accelerometry data.

Roles of Tunneling, Multiphoton Ionization, and Cascade Ionization for Femtosecond Optical Breakdown in Aqueous Media

DTIC Science & Technology

2009-09-01

observed in the wavelength dependence of femtosecond breakdown would indicate a significant role of multiphoton ionization compared to tunneling ...relevant for femtosecond breakdown, and tunnel ionization featuring no Ith() dependence becomes ever more with decreasing pulse duration. However, it...c) Figure 4.22 Wavelength dependence of ionization probabilities by a) avalanche, b) multiphoton, and c) tunneling ionization. 1

The Pathology of Chronic Obstructive Pulmonary Disease: Progress in the 20th and 21st Centuries.

PubMed

Berg, Kyra; Wright, Joanne L

2016-12-01

Chronic obstructive pulmonary disease (COPD) is a major cause of morbidity and is the fourth leading cause of death worldwide. There has been significant progress in the pathologic description and pathophysiologic analysis of COPD in the 20th and 21st centuries. We review the history, progression, and significance of pathologic alterations in COPD, including emphysematous changes, airway alterations, and vascular alterations. We also indicate what pathologic features of COPD the practicing pathologist should be describing in standard surgical and autopsy specimens.

Using the Theoretical Domains Framework (TDF) to understand adherence to multiple evidence-based indicators in primary care: a qualitative study.

PubMed

Lawton, Rebecca; Heyhoe, Jane; Louch, Gemma; Ingleson, Emma; Glidewell, Liz; Willis, Thomas A; McEachan, Rosemary R C; Foy, Robbie

2016-08-08

There are recognised gaps between evidence and practice in general practice, a setting posing particular implementation challenges. We earlier screened clinical guideline recommendations to derive a set of 'high-impact' indicators based upon criteria including potential for significant patient benefit, scope for improved practice and amenability to measurement using routinely collected data. Here, we explore health professionals' perceived determinants of adherence to these indicators, examining the degree to which determinants were indicator-specific or potentially generalisable across indicators. We interviewed 60 general practitioners, practice nurses and practice managers in West Yorkshire, the UK, about adherence to four indicators: avoidance of risky prescribing; treatment targets in type 2 diabetes; blood pressure targets in treated hypertension; and anticoagulation in atrial fibrillation. Interview questions drew upon the Theoretical Domains Framework (TDF). Data were analysed using framework analysis. Professional role and identity and environmental context and resources featured prominently across all indicators whilst the importance of other domains, for example, beliefs about consequences, social influences and knowledge varied across indicators. We identified five meta-themes representing more general organisational and contextual factors common to all indicators. The TDF helped elicit a wide range of reported determinants of adherence to 'high-impact' indicators in primary care. It was more difficult to pinpoint which determinants, if targeted by an implementation strategy, would maximise change. The meta-themes broadly underline the need to align the design of interventions targeting general practices with higher level supports and broader contextual considerations. However, our findings suggest that it is feasible to develop interventions to promote the uptake of different evidence-based indicators which share common features whilst also including content-specific adaptations.

Mobilization and degradation of particulate organic carbon from retrogressive thaw slumps in the western Canadian Arctic

NASA Astrophysics Data System (ADS)

Shakil, S.; Tank, S. E.; Kokelj, S.

2016-12-01

Rapid arctic climate warming has contributed to a significant intensification in the rate and occurrence of thermokarst features which can cause large quantities of frozen organic carbon to suddenly become an active part of the contemporary carbon cycle. Mobilized organic carbon becomes susceptible to bacterial decomposition to CO2, which can then act as a significant positive feedback to climate change. Increasingly, studies are showing dissolved organic carbon (DOC) released from thawing permafrost is highly biodegradable, however, we know little about the biodegradability of permafrost-derived particulate organic carbon (POC). On the Peel Plateau, NWT, Canada, where a warming and wetting climate has intensified the activity of massive retrogressive thaw slumps (RTS), and where some of the Arctic's largest RTS features occur, POC can be more than an order of magnitude greater in streams impacted by an RTS feature when compared to upstream, un-impacted locations, and this mobilization causes POC concentrations to be more than 200 times greater than DOC downstream of slumps. Furthermore, POC released from RTS features can be 6,000 to 13,000 years older than POC in un-impacted streams, indicating a significant mobilization of permafrost carbon in the particulate form. To determine the biodegradability of RTS-released POC in this region, incubations using water samples collected upstream, at, and downstream of RTS sites were conducted during the summer of 2015. Dissolved oxygen measurements were taken 1-2 times per day, and samples for POC and DOC concentration, SUVA254, and bacterial abundance were collected at 0 days, 7 days, and 11 days. Treatments containing a spike of RTS-runoff in filtered water declined in oxygen at a rate as much as 10 times greater than treatments containing filtered DOC controls and unfiltered upstream water indicating that the released of RTS-derived POC substantially increases carbon mineralization in impacted streams. This pool of organic carbon could therefore substantially contribute to the transfer of organic carbon from permafrost soils to the atmospheric carbon pool. Ongoing work is examining the balance between POC decomposition during downstream transport and re-sequestration into streambed sediments.

Nonlinear, non-stationary image processing technique for eddy current NDE

NASA Astrophysics Data System (ADS)

Yang, Guang; Dib, Gerges; Kim, Jaejoon; Zhang, Lu; Xin, Junjun; Udpa, Lalita

2012-05-01

Automatic analysis of eddy current (EC) data has facilitated the analysis of large volumes of data generated in the inspection of steam generator tubes in nuclear power plants. The traditional procedure for analysis of EC data includes data calibration, pre-processing, region of interest (ROI) detection, feature extraction and classification. Accurate ROI detection has been enhanced by pre-processing, which involves reducing noise and other undesirable components as well as enhancing defect indications in the raw measurement. This paper presents the Hilbert-Huang Transform (HHT) for feature extraction and support vector machine (SVM) for classification. The performance is shown to significantly better than the existing rule based classification approach used in industry.

Lithium Ion Battery (LIB) Charger: Spacesuit Battery Charger Design with 2-Fault Tolerance to Catastrophic Hazards

NASA Technical Reports Server (NTRS)

Darcy, Eric; Davies, Frank

2009-01-01

Charger design that is 2-fault tolerant to catastrophic has been achieved for the Spacesuit Li-ion Battery with key features. Power supply control circuit and 2 microprocessors independently control against overcharge. 3 microprocessor control against undercharge (false positive: Go for EVA) conditions. 2 independent channels provide functional redundancy. Capable of charge balancing cell banks in series. Cell manufacturing and performance uniformity is excellent with both designs. Once a few outliers are removed, LV cells are slightly more uniform than MoliJ cells. If cell balance feature of charger is ever invoked, it will be an indication of a significant degradation issue, not a nominal condition.

Bearing performance degradation assessment based on time-frequency code features and SOM network

NASA Astrophysics Data System (ADS)

Zhang, Yan; Tang, Baoping; Han, Yan; Deng, Lei

2017-04-01

Bearing performance degradation assessment and prognostics are extremely important in supporting maintenance decision and guaranteeing the system’s reliability. To achieve this goal, this paper proposes a novel feature extraction method for the degradation assessment and prognostics of bearings. Features of time-frequency codes (TFCs) are extracted from the time-frequency distribution using a hybrid procedure based on short-time Fourier transform (STFT) and non-negative matrix factorization (NMF) theory. An alternative way to design the health indicator is investigated by quantifying the similarity between feature vectors using a self-organizing map (SOM) network. On the basis of this idea, a new health indicator called time-frequency code quantification error (TFCQE) is proposed to assess the performance degradation of the bearing. This indicator is constructed based on the bearing real-time behavior and the SOM model that is previously trained with only the TFC vectors under the normal condition. Vibration signals collected from the bearing run-to-failure tests are used to validate the developed method. The comparison results demonstrate the superiority of the proposed TFCQE indicator over many other traditional features in terms of feature quality metrics, incipient degradation identification and achieving accurate prediction. Highlights • Time-frequency codes are extracted to reflect the signals’ characteristics. • SOM network served as a tool to quantify the similarity between feature vectors. • A new health indicator is proposed to demonstrate the whole stage of degradation development. • The method is useful for extracting the degradation features and detecting the incipient degradation. • The superiority of the proposed method is verified using experimental data.

Analysis of DCE-MRI features in tumor and the surrounding stroma for prediction of Ki-67 proliferation status in breast cancer

NASA Astrophysics Data System (ADS)

Li, Hui; Fan, Ming; Zhang, Peng; Li, Yuanzhe; Cheng, Hu; Zhang, Juan; Shao, Guoliang; Li, Lihua

2018-03-01

Breast cancer, with its high heterogeneity, is the most common malignancies in women. In addition to the entire tumor itself, tumor microenvironment could also play a fundamental role on the occurrence and development of tumors. The aim of this study is to investigate the role of heterogeneity within a tumor and the surrounding stromal tissue in predicting the Ki-67 proliferation status of oestrogen receptor (ER)-positive breast cancer patients. To this end, we collected 62 patients imaged with preoperative dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) for analysis. The tumor and the peritumoral stromal tissue were segmented into 8 shells with 5 mm width outside of tumor. The mean enhancement rate in the stromal shells showed a decreasing order if their distances to the tumor increase. Statistical and texture features were extracted from the tumor and the surrounding stromal bands, and multivariate logistic regression classifiers were trained and tested based on these features. An area under the receiver operating characteristic curve (AUC) were calculated to evaluate performance of the classifiers. Furthermore, the statistical model using features extracted from boundary shell next to the tumor produced AUC of 0.796+/-0.076, which is better than that using features from the other subregions. Furthermore, the prediction model using 7 features from the entire tumor produced an AUC value of 0.855+/-0.065. The classifier based on 9 selected features extracted from peritumoral stromal region showed an AUC value of 0.870+/-0.050. Finally, after fusion of the predictive model obtained from entire tumor and the peritumoral stromal regions, the classifier performance was significantly improved with AUC of 0.920. The results indicated that heterogeneity in tumor boundary and peritumoral stromal region could be valuable in predicting the indicator associated with prognosis.

Authenticity in Obesity Public Service Announcements: Influence of Spokesperson Type, Viewer Weight, and Source Credibility on Diet, Exercise, Information Seeking, and Electronic Word-of-Mouth Intentions.

PubMed

Phua, Joe; Tinkham, Spencer

2016-01-01

This study examined the joint influence of spokesperson type in obesity public service announcements (PSAs) and viewer weight on diet intention, exercise intention, information seeking, and electronic word-of-mouth (eWoM) intention. Results of a 2 (spokesperson type: real person vs. actor) × 2 (viewer weight: overweight vs. non-overweight) between-subjects experiment indicated that overweight viewers who saw the PSA featuring the real person had the highest diet intention, exercise intention, information seeking, and eWoM intention. Parasocial interaction was also found to mediate the relationships between spokesperson type/viewer weight and two of the dependent variables: diet intention and exercise intention. In addition, viewers who saw the PSA featuring the real person rated the spokesperson as significantly higher on source credibility (trustworthiness, competence, and goodwill) than those who saw the PSA featuring the actor.

Automatic identification of land uses from ERTS-1 data obtained over Milwaukee, Wisconsin

NASA Technical Reports Server (NTRS)

Baumgardner, M. F.; Landgrebe, D. A. (Principal Investigator); Kramer, H. H.

1972-01-01

The author has identified the following significant results. Spectrally, thirteen classes of ground cover were identified within Milwaukee County: five classes of water, grassy open areas, beach, two classes of road, woods, suburban, inner city, and industry. A distinct concentric pattern of land use was identified in the county radiating outward from the central business district. The first ring has a principal feature, termed the inner city, which is indicative of the older part of the county. In the second ring, the land use becomes more complex, consisting of suburban areas, parks, and varied institutional features. The third general ring consists primarily of open, grassy land, with scattered residential subdivisions, wood lots, and small water bodies. The five classes of water identified suggest differences in depth, turbidity, and/or color. A number of major roads were identified. Other spectrally identifiable features included the larger county parks and larger cemeteries.

'Athlete's heart' in prepubertal children.

PubMed

Rowland, T W; Delaney, B C; Siconolfi, S F

1987-05-01

Bradycardia, cardiomegaly, heart murmurs, and ECG changes are typically observed in adult endurance athletes, but frequency of such changes among children involved in sports training is unclear. Pediatricians need to be aware of whether these features of the "athlete's heart" occur in their patients, because such features may mimic those of cardiac disease. Fourteen prepubertal competitive male swimmers were evaluated by physical examination, ECG and echocardiogram, and findings were compared to those of a group of active but nontrained control boys. Lower resting heart rates and echocardiographic manifestations of chronic left ventricular volume overload were observed among the swimmers. These changes were not manifest on physical examination, however, and no significant ECG alterations were identified among the athletes. These findings indicate that, although features of the athlete's heart are present in children involved in endurance training, seldom will these findings simulate heart disease or be apparent on routine clinical examination.

Effect of diesel exhaust pollution on cuticular and epidermal features of Lantana camara L. and Syzygium cuminii L. (Skeels. )

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kulshreshtha, K.; Farooqui, A.; Srivastava, K.

1994-02-01

Cuticular and epidermal features of leaves of two common plant species namely, Lantana camara L. and Syzygium cuminii L. (Skeel.) growing in polluted and healthy (control) environments were studied under light and scanning electron microscopes. Polluted leaf samples were collected from the plants growing near a diesel generating set used in running a tube well. The study shows that in polluted populations of Lantana camara, the trichome frequency had increased four fold. In Syzygium cuminii, the stomatal openings were filled with dust and a tendency towards callus formation was also observed. The epidermal cells were comparatively thick walled and weremore » broken at certain places. The changes observed in the cuticular and epidermal features of polluted populations of the investigated species indicate their significance as bioindicators of atmospheric pollution. 9 refs., 2 figs., 1 tab.« less

Utilizing ERTS-A imagery for tectonic analysis through study of Big Horn Mountains Region

NASA Technical Reports Server (NTRS)

Hoppin, R. A. (Principal Investigator)

1973-01-01

The author has identified the following significant results. NASA-provided color composite (1048-17234) which includes the southeastern portion of the Bighorn Mountains and the western Powder River basin is of excellent quality. The considerable variations in the red hues indicate that vegetational mapping will be enhanced over the black and white. Some additional delineation of rock units can be made, particularly the Chugwater formation. Preliminary look at just received winter scenes indicates that topographic features are enhanced both due to the snow cover and to the lower sun angle.

Parsec-Scale Kinematic and Polarization Properties of MOJAVE AGN Jets

NASA Astrophysics Data System (ADS)

Lister, Matthew L.

2013-12-01

We describe the parsec-scale kinematics and statistical polarization properties of 200 AGN jets based on 15 GHz VLBA data obtained between 1994 Aug 31 and 2011 May 1. Nearly all of the 60 most heavily observed jets show significant changes in their innermost position angle over a 12 to 16 year interval, ranging from 10° to 150° on the sky, corresponding to intrinsic variations of ~ 0.5° to ~ 2°. The BL Lac jets show smaller variations than quasars. Roughly half of the heavily observed jets show systematic position angle trends with time, and 20 show indications of oscillatory behavior. The time spans of the data sets are too short compared to the fitted periods (5 to 12 y), however, to reliably establish periodicity. The rapid changes and large jumps in position angle seen in many cases suggest that the superluminal AGN jet features occupy only a portion of the entire jet cross section, and may be energized portions of thin instability structures within the jet. We have derived vector proper motions for 887 moving features in 200 jets having at least five VLBA epochs. For 557 well-sampled features, there are sufficient data to additionally study possible accelerations. The moving features are generally non-ballistic, with 70% of the well-sampled features showing either significant accelerations or non-radial motions. Inward motions are rare (2% of all features), are slow (< 0.1 mas per y), are more prevalent in BL Lac jets, and are typically found within 1 mas of the unresolved core feature. There is a general trend of increasing apparent speed with distance down the jet for both radio galaxies and BL Lac objects. In most jets, the speeds of the features cluster around a characteristic value, yet there is a considerable dispersion in the distribution. Orientation variations within the jet cannot fully account for the dispersion, implying that the features have a range of Lorentz factor and/or pattern speed. Very slow pattern speed features are rare, comprising only 4% of the sample, and are more prevalent in radio galaxy and BL Lac jets. We confirm a previously reported upper envelope to the distribution of speed versus beamed luminosity for moving jet features. Below 1026 W Hz-1 there is a fall-off in maximum speed with decreasing 15 GHz radio luminosity. A preliminary analysis of the multi-epoch jet polarization properties indicates a wide range of behavior in the core electric vector position angles over time, with the latter remaining relatively stable in some jets, and varying rapidly in others. The fractional polarization level generally increases down the jet, and high-synchrotron peaked (HSP) blazars tend to have lower core fractional polarization levels. A general trend of decreasing maximum jet speed for higher synchrotron peaked blazars further suggests lower Doppler factors in the radio-emitting jets of HSP BL Lac objects.

A comparative study of hematological parameters of α and β thalassemias in a high prevalence zone: Saudi Arabia.

PubMed

Mehdi, Syed Riaz; Al Dahmash, Badr Abdullah

2011-09-01

Saudi Arabia falls in the high prevalent zone of αα and β thalassemias. Early screening for the type of thalassemia is essential for further investigations and management. The study was carried out to differentiate the type of thalassemia based on red cell indices and other hematological parameters. The study was carried out on 991 clinically suspected cases of thalassemias in Riyadh, Saudi Arabia. The hematological parameters were studied on Coulter STKS. Cellulose acetate hemoglobin electrophoresis and high-performance liquid chromatography (HPLC) were performed on all the blood samples. Gene deletion studies were carried out by restriction fragment length polymorphism (RFLP) technique using the restriction endonucleases Bam HI. Statistical analysis was performed on SPSS 11.5 version. The hemoglobin electrophoresis and gene studies revealed that there were 406 (40.96%) and 59 (5.95 %) cases of β thalassemia trait and β thalassemia major respectively including adults and children. 426 cases of various deletion forms of α thalassemias were seen. Microcytosis was a common feature in β thalassemias trait and (-α/-α) and (--/αα) types of α thalassemias. MCH was a more significant distinguishing feature among thalassemias. β thalassemia major and α thalassemia (-α/αα) had almost normal hematological parameters. MCV and RBC counts are not statistically significant features for discriminating between α and β thalassemias. There is need for development of a discrimination index to differentiate between α and β thalassemias traits on the lines of discriminatory Indices available for distinguishing β thalassemias trait from iron deficiency anemia.

Understanding the usage of content in a mental health intervention for depression: an analysis of log data.

PubMed

Van Gemert-Pijnen, Julia Ewc; Kelders, Saskia M; Bohlmeijer, Ernst T

2014-01-31

Web-based interventions for the early treatment of depressive symptoms can be considered effective in reducing mental complaints. However, there is a limited understanding of which elements in an intervention contribute to effectiveness. For efficiency and effectiveness of interventions, insight is needed into the use of content and persuasive features. The aims of this study were (1) to illustrate how log data can be used to understand the uptake of the content of a Web-based intervention that is based on the acceptance and commitment therapy (ACT) and (2) to discover how log data can be of value for improving the incorporation of content in Web-based interventions. Data from 206 participants (out of the 239) who started the first nine lessons of the Web-based intervention, Living to the Full, were used for a secondary analysis of a subset of the log data of the parent study about adherence to the intervention. The log files used in this study were per lesson: login, start mindfulness, download mindfulness, view success story, view feedback message, start multimedia, turn on text-message coach, turn off text-message coach, and view text message. Differences in usage between lessons were explored with repeated measures ANOVAs (analysis of variance). Differences between groups were explored with one-way ANOVAs. To explore the possible predictive value of the login per lesson quartiles on the outcome measures, four linear regressions were used with login quartiles as predictor and with the outcome measures (Center for Epidemiologic Studies-Depression [CES-D] and the Hospital Anxiety and Depression Scale-Anxiety [HADS-A] on post-intervention and follow-up) as dependent variables. A significant decrease in logins and in the use of content and persuasive features over time was observed. The usage of features varied significantly during the treatment process. The usage of persuasive features increased during the third part of the ACT (commitment to value-based living), which might indicate that at that stage motivational support was relevant. Higher logins over time (9 weeks) corresponded with a higher usage of features (in most cases significant); when predicting depressive symptoms at post-intervention, the linear regression yielded a significant model with login quartile as a significant predictor (explained variance is 2.7%). A better integration of content and persuasive features in the design of the intervention and a better intra-usability of features within the system are needed to identify which combination of features works best for whom. Pattern recognition can be used to tailor the intervention based on usage patterns from the earlier lessons and to support the uptake of content essential for therapy. An adaptable interface for a modular composition of therapy features supposes a dynamic approach for Web-based treatment; not a predefined path for all, but a flexible way to go through all features that have to be used.

Understanding the Usage of Content in a Mental Health Intervention for Depression: An Analysis of Log Data

PubMed Central

2014-01-01

Background Web-based interventions for the early treatment of depressive symptoms can be considered effective in reducing mental complaints. However, there is a limited understanding of which elements in an intervention contribute to effectiveness. For efficiency and effectiveness of interventions, insight is needed into the use of content and persuasive features. Objective The aims of this study were (1) to illustrate how log data can be used to understand the uptake of the content of a Web-based intervention that is based on the acceptance and commitment therapy (ACT) and (2) to discover how log data can be of value for improving the incorporation of content in Web-based interventions. Methods Data from 206 participants (out of the 239) who started the first nine lessons of the Web-based intervention, Living to the Full, were used for a secondary analysis of a subset of the log data of the parent study about adherence to the intervention. The log files used in this study were per lesson: login, start mindfulness, download mindfulness, view success story, view feedback message, start multimedia, turn on text-message coach, turn off text-message coach, and view text message. Differences in usage between lessons were explored with repeated measures ANOVAs (analysis of variance). Differences between groups were explored with one-way ANOVAs. To explore the possible predictive value of the login per lesson quartiles on the outcome measures, four linear regressions were used with login quartiles as predictor and with the outcome measures (Center for Epidemiologic Studies—Depression [CES-D] and the Hospital Anxiety and Depression Scale—Anxiety [HADS-A] on post-intervention and follow-up) as dependent variables. Results A significant decrease in logins and in the use of content and persuasive features over time was observed. The usage of features varied significantly during the treatment process. The usage of persuasive features increased during the third part of the ACT (commitment to value-based living), which might indicate that at that stage motivational support was relevant. Higher logins over time (9 weeks) corresponded with a higher usage of features (in most cases significant); when predicting depressive symptoms at post-intervention, the linear regression yielded a significant model with login quartile as a significant predictor (explained variance is 2.7%). Conclusions A better integration of content and persuasive features in the design of the intervention and a better intra-usability of features within the system are needed to identify which combination of features works best for whom. Pattern recognition can be used to tailor the intervention based on usage patterns from the earlier lessons and to support the uptake of content essential for therapy. An adaptable interface for a modular composition of therapy features supposes a dynamic approach for Web-based treatment; not a predefined path for all, but a flexible way to go through all features that have to be used. PMID:24486914

Spatial analysis of vector-borne infectious diseases and ecological indicators using GIS and remote sensing

NASA Astrophysics Data System (ADS)

Anh, N. K.; Liou, Y. A.

2017-12-01

Ecological and climate indicators play a vital role in defining patterns of human activities and behaviors, such as seasonal features, migration, winter-summer lifestyles, which in turn might be associated with vector-borne disease habitats and transmission risks. Remote sensing has been instrumental in deriving environmental variables and indicators. GIS is shown to be a powerful tool in spatiotemporal visualization and distribution of vector-borne diseases and for analysis of associations between environmental conditions and characteristics of vector-borne habitats. Vietnam is in the sub-tropical climate zone with high humidity and abundant precipitation, while the distribution of precipitation is uneven leading to frequently annual occurrence of drought and flood disasters. Moreover, urban heat island effect is significantly enhanced in urbanized areas in recent years. The increase in the frequency and magnitude of severity of weather extremes that are potentially linked to climate change and anthropogenic processes have highlighted the demand of research into health risk assessment and adaptive capacity. This research focuses on the analysis of physical features of environmental indicators and its association with vector-borne diseases as well as adaptive capacity. The study illustrates how remotely sensed data has been utilized in geohealth applications, surveillance, and health risk mapping. In addition, promising possibilities of allowing disease early-warning systems with citizen participation platform will be proposed. Keywords: Vector-borne diseases; environmental indicators; remote sensing; GIS; Vietnam.

Visual Feature Integration Indicated by pHase-Locked Frontal-Parietal EEG Signals

PubMed Central

Phillips, Steven; Takeda, Yuji; Singh, Archana

2012-01-01

The capacity to integrate multiple sources of information is a prerequisite for complex cognitive ability, such as finding a target uniquely identifiable by the conjunction of two or more features. Recent studies identified greater frontal-parietal synchrony during conjunctive than non-conjunctive (feature) search. Whether this difference also reflects greater information integration, rather than just differences in cognitive strategy (e.g., top-down versus bottom-up control of attention), or task difficulty is uncertain. Here, we examine the first possibility by parametrically varying the number of integrated sources from one to three and measuring phase-locking values (PLV) of frontal-parietal EEG electrode signals, as indicators of synchrony. Linear regressions, under hierarchical false-discovery rate control, indicated significant positive slopes for number of sources on PLV in the 30–38 Hz, 175–250 ms post-stimulus frequency-time band for pairs in the sagittal plane (i.e., F3-P3, Fz-Pz, F4-P4), after equating conditions for behavioural performance (to exclude effects due to task difficulty). No such effects were observed for pairs in the transverse plane (i.e., F3-F4, C3-C4, P3-P4). These results provide support for the idea that anterior-posterior phase-locking in the lower gamma-band mediates integration of visual information. They also provide a potential window into cognitive development, seen as developing the capacity to integrate more sources of information. PMID:22427847

Visual feature integration indicated by pHase-locked frontal-parietal EEG signals.

PubMed

Phillips, Steven; Takeda, Yuji; Singh, Archana

2012-01-01

The capacity to integrate multiple sources of information is a prerequisite for complex cognitive ability, such as finding a target uniquely identifiable by the conjunction of two or more features. Recent studies identified greater frontal-parietal synchrony during conjunctive than non-conjunctive (feature) search. Whether this difference also reflects greater information integration, rather than just differences in cognitive strategy (e.g., top-down versus bottom-up control of attention), or task difficulty is uncertain. Here, we examine the first possibility by parametrically varying the number of integrated sources from one to three and measuring phase-locking values (PLV) of frontal-parietal EEG electrode signals, as indicators of synchrony. Linear regressions, under hierarchical false-discovery rate control, indicated significant positive slopes for number of sources on PLV in the 30-38 Hz, 175-250 ms post-stimulus frequency-time band for pairs in the sagittal plane (i.e., F3-P3, Fz-Pz, F4-P4), after equating conditions for behavioural performance (to exclude effects due to task difficulty). No such effects were observed for pairs in the transverse plane (i.e., F3-F4, C3-C4, P3-P4). These results provide support for the idea that anterior-posterior phase-locking in the lower gamma-band mediates integration of visual information. They also provide a potential window into cognitive development, seen as developing the capacity to integrate more sources of information.

Diagnosing Autism Spectrum Disorder from Brain Resting-State Functional Connectivity Patterns Using a Deep Neural Network with a Novel Feature Selection Method.

PubMed

Guo, Xinyu; Dominick, Kelli C; Minai, Ali A; Li, Hailong; Erickson, Craig A; Lu, Long J

2017-01-01

The whole-brain functional connectivity (FC) pattern obtained from resting-state functional magnetic resonance imaging data are commonly applied to study neuropsychiatric conditions such as autism spectrum disorder (ASD) by using different machine learning models. Recent studies indicate that both hyper- and hypo- aberrant ASD-associated FCs were widely distributed throughout the entire brain rather than only in some specific brain regions. Deep neural networks (DNN) with multiple hidden layers have shown the ability to systematically extract lower-to-higher level information from high dimensional data across a series of neural hidden layers, significantly improving classification accuracy for such data. In this study, a DNN with a novel feature selection method (DNN-FS) is developed for the high dimensional whole-brain resting-state FC pattern classification of ASD patients vs. typical development (TD) controls. The feature selection method is able to help the DNN generate low dimensional high-quality representations of the whole-brain FC patterns by selecting features with high discriminating power from multiple trained sparse auto-encoders. For the comparison, a DNN without the feature selection method (DNN-woFS) is developed, and both of them are tested with different architectures (i.e., with different numbers of hidden layers/nodes). Results show that the best classification accuracy of 86.36% is generated by the DNN-FS approach with 3 hidden layers and 150 hidden nodes (3/150). Remarkably, DNN-FS outperforms DNN-woFS for all architectures studied. The most significant accuracy improvement was 9.09% with the 3/150 architecture. The method also outperforms other feature selection methods, e.g., two sample t -test and elastic net. In addition to improving the classification accuracy, a Fisher's score-based biomarker identification method based on the DNN is also developed, and used to identify 32 FCs related to ASD. These FCs come from or cross different pre-defined brain networks including the default-mode, cingulo-opercular, frontal-parietal, and cerebellum. Thirteen of them are statically significant between ASD and TD groups (two sample t -test p < 0.05) while 19 of them are not. The relationship between the statically significant FCs and the corresponding ASD behavior symptoms is discussed based on the literature and clinician's expert knowledge. Meanwhile, the potential reason of obtaining 19 FCs which are not statistically significant is also provided.

Breaking Open the Black Box: Isolating the Most Potent Features of a Web and Mobile Phone-Based Intervention for Depression, Anxiety, and Stress.

PubMed

Whitton, Alexis E; Proudfoot, Judith; Clarke, Janine; Birch, Mary-Rose; Parker, Gordon; Manicavasagar, Vijaya; Hadzi-Pavlovic, Dusan

2015-01-01

Internet-delivered mental health (eMental Health) interventions produce treatment effects similar to those observed in face-to-face treatment. However, there is a large degree of variation in treatment effects observed from program to program, and eMental Health interventions remain somewhat of a black box in terms of the mechanisms by which they exert their therapeutic benefit. Trials of eMental Health interventions typically use large sample sizes and therefore provide an ideal context within which to systematically investigate the therapeutic benefit of specific program features. Furthermore, the growth and impact of mobile phone technology within eMental Health interventions provides an opportunity to examine associations between symptom improvement and the use of program features delivered across computer and mobile phone platforms. The objective of this study was to identify the patterns of program usage associated with treatment outcome in a randomized controlled trial (RCT) of a fully automated, mobile phone- and Web-based self-help program, "myCompass", for individuals with mild-to-moderate symptoms of depression, anxiety, and/or stress. The core features of the program include interactive psychotherapy modules, a symptom tracking feature, short motivational messages, symptom tracking reminders, and a diary, with many of these features accessible via both computer and mobile phone. Patterns of program usage were recorded for 231 participants with mild-to-moderate depression, anxiety, and/or stress, and who were randomly allocated to receive access to myCompass for seven weeks during the RCT. Depression, anxiety, stress, and functional impairment were examined at baseline and at eight weeks. Log data indicated that the most commonly used components were the short motivational messages (used by 68.4%, 158/231 of participants) and the symptom tracking feature (used by 61.5%, 142/231 of participants). Further, after controlling for baseline symptom severity, increased use of these alert features was associated with significant improvements in anxiety and functional impairment. Associations between use of symptom tracking reminders and improved treatment outcome remained significant after controlling for frequency of symptom tracking. Although correlations were not statistically significant, reminders received via SMS (ie, text message) were more strongly associated with symptom reduction than were reminders received via email. These findings indicate that alerts may be an especially potent component of eMental Health interventions, both via their association with enhanced program usage, as well as independently. Although there was evidence of a stronger association between symptom improvement and use of alerts via the mobile phone platform, the degree of overlap between use of email and SMS alerts may have precluded identification of alert delivery modalities that were most strongly associated with symptom reduction. Future research using random assignment to computer and mobile delivery is needed to fully determine the most ideal platform for delivery of this and other features of online interventions. Australian New Zealand Clinical Trials Registry (ACTRN): 12610000625077; http://www.anzctr.org.au/TrialSearch.aspx? (Archived by WebCite http://www.webcitation.org/6WPqHK0mQ).

Breaking Open the Black Box: Isolating the Most Potent Features of a Web and Mobile Phone-Based Intervention for Depression, Anxiety, and Stress

PubMed Central

Proudfoot, Judith; Clarke, Janine; Birch, Mary-Rose; Parker, Gordon; Manicavasagar, Vijaya; Hadzi-Pavlovic, Dusan

2015-01-01

Background Internet-delivered mental health (eMental Health) interventions produce treatment effects similar to those observed in face-to-face treatment. However, there is a large degree of variation in treatment effects observed from program to program, and eMental Health interventions remain somewhat of a black box in terms of the mechanisms by which they exert their therapeutic benefit. Trials of eMental Health interventions typically use large sample sizes and therefore provide an ideal context within which to systematically investigate the therapeutic benefit of specific program features. Furthermore, the growth and impact of mobile phone technology within eMental Health interventions provides an opportunity to examine associations between symptom improvement and the use of program features delivered across computer and mobile phone platforms. Objective The objective of this study was to identify the patterns of program usage associated with treatment outcome in a randomized controlled trial (RCT) of a fully automated, mobile phone- and Web-based self-help program, “myCompass”, for individuals with mild-to-moderate symptoms of depression, anxiety, and/or stress. The core features of the program include interactive psychotherapy modules, a symptom tracking feature, short motivational messages, symptom tracking reminders, and a diary, with many of these features accessible via both computer and mobile phone. Methods Patterns of program usage were recorded for 231 participants with mild-to-moderate depression, anxiety, and/or stress, and who were randomly allocated to receive access to myCompass for seven weeks during the RCT. Depression, anxiety, stress, and functional impairment were examined at baseline and at eight weeks. Results Log data indicated that the most commonly used components were the short motivational messages (used by 68.4%, 158/231 of participants) and the symptom tracking feature (used by 61.5%, 142/231 of participants). Further, after controlling for baseline symptom severity, increased use of these alert features was associated with significant improvements in anxiety and functional impairment. Associations between use of symptom tracking reminders and improved treatment outcome remained significant after controlling for frequency of symptom tracking. Although correlations were not statistically significant, reminders received via SMS (ie, text message) were more strongly associated with symptom reduction than were reminders received via email. Conclusions These findings indicate that alerts may be an especially potent component of eMental Health interventions, both via their association with enhanced program usage, as well as independently. Although there was evidence of a stronger association between symptom improvement and use of alerts via the mobile phone platform, the degree of overlap between use of email and SMS alerts may have precluded identification of alert delivery modalities that were most strongly associated with symptom reduction. Future research using random assignment to computer and mobile delivery is needed to fully determine the most ideal platform for delivery of this and other features of online interventions. Trial Registration Australian New Zealand Clinical Trials Registry (ACTRN): 12610000625077; http://www.anzctr.org.au/TrialSearch.aspx? (Archived by WebCite http://www.webcitation.org/6WPqHK0mQ). PMID:26543909

A land use regression application into assessing spatial variation of intra-urban fine particulate matter (PM2.5) and nitrogen dioxide (NO2) concentrations in City of Shanghai, China.

PubMed

Liu, Chao; Henderson, Barron H; Wang, Dongfang; Yang, Xinyuan; Peng, Zhong-Ren

2016-09-15

Intra-urban assessment of air pollution exposure has become a priority study while international attention was attracted to PM2.5 pollution in China in recent years. Land Use Regression (LUR), which has previously been proved to be a feasible way to describe the relationship between land use and air pollution level in European and American cities, was employed in this paper to explain the correlations and spatial variations in Shanghai, China. PM2.5 and NO2 concentrations at 35-45 monitoring locations were selected as dependent variables, and a total of 44 built environmental factors were extracted as independent variables. Only five factors showed significant explanatory value for both PM2.5 and NO2 models: longitude, distance from monitors to the ocean, highway intensity, waterbody area, and industrial land area for PM2.5 model; residential area, distance to the coast, industrial area, urban district, and highway intensity for NO2 model. Respectively, both PM2.5 and NO2 showed anti-correlation with coastal proximity (an indicator of clean air dilution) and correlation with highway and industrial intensity (source indicators). NO2 also showed significant correlation with local indicators of population density (residential intensity and urban classification), while PM2.5 showed significant correlation with regional dilution (longitude as a indicator of distance from polluted neighbors and local water features). Both adjusted R squared values were strong with PM2.5 (0.88) being higher than NO2 (0.62). The LUR was then used to produce continuous concentration fields for NO2 and PM2.5 to illustrate the features and, potentially, for use by future studies. Comparison to PM2.5 studies in New York and Beijing show that Shanghai PM2.5 pollutant distribution was more sensitive to geographic location and proximity to neighboring regions. Copyright © 2015. Published by Elsevier B.V.

Mentoring Programs to Affect Delinquency and Associated Outcomes of Youth At-Risk: A Comprehensive Meta-Analytic Reviewi

PubMed Central

Tolan, Patrick H.; Henry, David B.; Schoeny, Michael S.; Lovegrove, Peter; Nichols, Emily

2013-01-01

Objectives To conduct a meta-analytic review of selective and indicated mentoring interventions for effects for youth at risk on delinquency and key associated outcomes (aggression, drug use, academic functioning). We also undertook the first systematic evaluation of intervention implementation features and organization and tested for effects of theorized key processes of mentor program effects. Methods Campbell Collaboration review inclusion criteria and procedures were used to search and evaluate the literature. Criteria included a sample defined as at-risk for delinquency due to individual behavior such as aggression or conduct problems or environmental characteristics such as residence in high-crime community. Studies were required to be random assignment or strong quasi-experimental design. Of 163 identified studies published 1970 - 2011, 46 met criteria for inclusion. Results Mean effects sizes were significant and positive for each outcome category (ranging form d =.11 for Academic Achievement to d = .29 for Aggression). Heterogeneity in effect sizes was noted for all four outcomes. Stronger effects resulted when mentor motivation was professional development but not by other implementation features. Significant improvements in effects were found when advocacy and emotional support mentoring processes were emphasized. Conclusions This popular approach has significant impact on delinquency and associated outcomes for youth at-risk for delinquency. While evidencing some features may relate to effects, the body of literature is remarkably lacking in details about specific program features and procedures. This persistent state of limited reporting seriously impedes understanding about how mentoring is beneficial and ability to maximize its utility. PMID:25386111

Computer-aided diagnostic system for detection of Hashimoto thyroiditis on ultrasound images from a Polish population.

PubMed

Acharya, U Rajendra; Sree, S Vinitha; Krishnan, M Muthu Rama; Molinari, Filippo; Zieleźnik, Witold; Bardales, Ricardo H; Witkowska, Agnieszka; Suri, Jasjit S

2014-02-01

Computer-aided diagnostic (CAD) techniques aid physicians in better diagnosis of diseases by extracting objective and accurate diagnostic information from medical data. Hashimoto thyroiditis is the most common type of inflammation of the thyroid gland. The inflammation changes the structure of the thyroid tissue, and these changes are reflected as echogenic changes on ultrasound images. In this work, we propose a novel CAD system (a class of systems called ThyroScan) that extracts textural features from a thyroid sonogram and uses them to aid in the detection of Hashimoto thyroiditis. In this paradigm, we extracted grayscale features based on stationary wavelet transform from 232 normal and 294 Hashimoto thyroiditis-affected thyroid ultrasound images obtained from a Polish population. Significant features were selected using a Student t test. The resulting feature vectors were used to build and evaluate the following 4 classifiers using a 10-fold stratified cross-validation technique: support vector machine, decision tree, fuzzy classifier, and K-nearest neighbor. Using 7 significant features that characterized the textural changes in the images, the fuzzy classifier had the highest classification accuracy of 84.6%, sensitivity of 82.8%, specificity of 87.0%, and a positive predictive value of 88.9%. The proposed ThyroScan CAD system uses novel features to noninvasively detect the presence of Hashimoto thyroiditis on ultrasound images. Compared to manual interpretations of ultrasound images, the CAD system offers a more objective interpretation of the nature of the thyroid. The preliminary results presented in this work indicate the possibility of using such a CAD system in a clinical setting after evaluating it with larger databases in multicenter clinical trials.

Differential transcriptomic responses of Biomphalaria glabrata (Gastropoda, Mollusca) to bacteria and metazoan parasites, Schistosoma mansoni and Echinostoma paraensei (Digenea, Platyhelminthes)

PubMed Central

Adema, Coen M; Hanington, Patrick C.; Lun, Cheng-Man; Rosenberg, George H.; Aragon, Anthony D; Stout, Barbara A; Richard, Mara L. Lennard; Gross, Paul S.; Loker, Eric S

2009-01-01

A 70-mer oligonucleotide-based microarray (1152 features) that emphasizes stress and immune responses factors was constructed to study transcriptomic responses of the snail Biomphalaria glabrata to different immune challenges. In addition to sequences with relevant putative ID and Gene Ontology (GO) annotation, the array features non-immune factors and unknown B. glabrata ESTs for functional gene discovery. The transcription profiles of B. glabrata (3 biological replicates, each a pool of 5 snails) were recorded at 12 hours post wounding, exposure to Gram negative or Gram positive bacteria (Escherichia coli and Micrococcus luteus, respectively), or infection with compatible trematode parasites (S. mansoni or E. paraensei, 20 miracidia/snail), relative to controls, using universal reference RNA. The data were subjected to Significance Analysis for Microarrays (SAM), with a false positive rate (FPR) ≤10%. Wounding yielded a modest differential expression profile (27 up/21 down) with affected features mostly dissimilar from other treatments. Partially overlapping, yet distinct expression profiles were recorded from snails challenged with E. coli (83 up/20 down) or M. luteus (120 up/42 down), mostly showing up-regulation of defense and stress-related features. Significantly altered expression of selected immune features indicates that B. glabrata detects and responds differently to compatible trematodes. Echinostoma paraensei infection was associated mostly with down regulation of many (immune-) transcripts (42 up/68 down), whereas S. mansoni exposure yielded a preponderance of up-regulated features (140 up/23 down), with only few known immune genes affected. These observations may reflect the divergent strategies developed by trematodes during their evolution as specialized pathogens of snails to negate host defense responses. Clearly, the immune defenses of B. glabrata distinguish and respond differently to various immune challenges. PMID:19962194

Accelerating object detection via a visual-feature-directed search cascade: algorithm and field programmable gate array implementation

NASA Astrophysics Data System (ADS)

Kyrkou, Christos; Theocharides, Theocharis

2016-07-01

Object detection is a major step in several computer vision applications and a requirement for most smart camera systems. Recent advances in hardware acceleration for real-time object detection feature extensive use of reconfigurable hardware [field programmable gate arrays (FPGAs)], and relevant research has produced quite fascinating results, in both the accuracy of the detection algorithms as well as the performance in terms of frames per second (fps) for use in embedded smart camera systems. Detecting objects in images, however, is a daunting task and often involves hardware-inefficient steps, both in terms of the datapath design and in terms of input/output and memory access patterns. We present how a visual-feature-directed search cascade composed of motion detection, depth computation, and edge detection, can have a significant impact in reducing the data that needs to be examined by the classification engine for the presence of an object of interest. Experimental results on a Spartan 6 FPGA platform for face detection indicate data search reduction of up to 95%, which results in the system being able to process up to 50 1024×768 pixels images per second with a significantly reduced number of false positives.

Accent on communication: the impact of regional and foreign accent on comprehension in adults with aphasia.

PubMed

Bruce, Carolyn; To, Cinn-Teng; Newton, Caroline

2012-01-01

This study explored whether an unfamiliar non-native accent, differing in both segmental and prosodic features was more difficult for individuals with aphasia to understand than an unfamiliar native accent, which differed in segmental features only. Comprehension, which was determined by accuracy judgments on true/false sentences, and speed of response were assessed in the following three conditions: a familiar Southern Standard British English (SSBE) accent, an unfamiliar native Grimsby accent, and an unfamiliar non-native Chinese accent. Thirty-four English speaking adults (17 people with and 17 people without aphasia) served as listeners for this study. All listeners made significantly more errors in the unfamiliar non-native accent, although this difficulty was more marked for those with aphasia. While there was no affect of speaker accent on the response times of listeners with aphasia, listeners without aphasia were significantly slower with the unfamiliar non-native accent. The results indicate that non-native accented speech affects comprehension even on simple tasks in ideal listening conditions. The findings suggest that speaker accent, especially accents varying in both segmental and prosodic features, can be a barrier to successful interactions between non-native accented speakers and native listeners, particularly those with aphasia.

Drug Target Protein-Protein Interaction Networks: A Systematic Perspective

PubMed Central

2017-01-01

The identification and validation of drug targets are crucial in biomedical research and many studies have been conducted on analyzing drug target features for getting a better understanding on principles of their mechanisms. But most of them are based on either strong biological hypotheses or the chemical and physical properties of those targets separately. In this paper, we investigated three main ways to understand the functional biomolecules based on the topological features of drug targets. There are no significant differences between targets and common proteins in the protein-protein interactions network, indicating the drug targets are neither hub proteins which are dominant nor the bridge proteins. According to some special topological structures of the drug targets, there are significant differences between known targets and other proteins. Furthermore, the drug targets mainly belong to three typical communities based on their modularity. These topological features are helpful to understand how the drug targets work in the PPI network. Particularly, it is an alternative way to predict potential targets or extract nontargets to test a new drug target efficiently and economically. By this way, a drug target's homologue set containing 102 potential target proteins is predicted in the paper. PMID:28691014

A continuous scale-space method for the automated placement of spot heights on maps

NASA Astrophysics Data System (ADS)

Rocca, Luigi; Jenny, Bernhard; Puppo, Enrico

2017-12-01

Spot heights and soundings explicitly indicate terrain elevation on cartographic maps. Cartographers have developed design principles for the manual selection, placement, labeling, and generalization of spot height locations, but these processes are work-intensive and expensive. Finding an algorithmic criterion that matches the cartographers' judgment in ranking the significance of features on a terrain is a difficult endeavor. This article proposes a method for the automated selection of spot heights locations representing natural features such as peaks, saddles and depressions. A lifespan of critical points in a continuous scale-space model is employed as the main measure of the importance of features, and an algorithm and a data structure for its computation are described. We also introduce a method for the comparison of algorithmically computed spot height locations with manually produced reference compilations. The new method is compared with two known techniques from the literature. Results show spot height locations that are closer to reference spot heights produced manually by swisstopo cartographers, compared to previous techniques. The introduced method can be applied to elevation models for the creation of topographic and bathymetric maps. It also ranks the importance of extracted spot height locations, which allows for a variation in the size of symbols and labels according to the significance of represented features. The importance ranking could also be useful for adjusting spot height density of zoomable maps in real time.

Exogenous determinants of early-life conditions, and mortality later in life.

PubMed

van den Berg, Gerard J; Doblhammer, Gabriele; Christensen, Kaare

2009-05-01

We analyze causal effects of conditions early in life on the individual mortality rate later in life. Conditions early in life are captured by transitory features of the macro-environment around birth, notably the state of the business cycle around birth, but also food price deviations, weather indicators, and demographic indicators. We argue that these features can only affect high-age mortality by way of the individual early-life conditions. Moreover, they are exogenous from the individual point of view, which is a methodological advantage compared to the use of unique characteristics of the newborn individual or his or her family or household as early-life indicators. We collected national annual time-series data on the above-mentioned indicators, and we combine these to the individual data records from the Danish Twin Registry covering births in 1873-1906. The empirical analyses (mostly based on the estimation of duration models) indicate a significant negative causal effect of economic conditions early in life on individual mortality rates at higher ages. If the national economic performance in the year of birth exceeds its trend value (i.e., if the business cycle is favorable) then the mortality rate later in life is lower. The implied effect on the median lifetime of those who survive until age 35 is about 10 months. A systematic empirical exploration of all macro-indicators reveals that economic conditions in the first years after birth also affect mortality rates later in life.

Kinematic measurements of the vocal-fold displacement waveform in typical children and adult populations: quantification of high-speed endoscopic videos.

PubMed

Patel, Rita; Donohue, Kevin D; Unnikrishnan, Harikrishnan; Kryscio, Richard J

2015-04-01

This article presents a quantitative method for assessing instantaneous and average lateral vocal-fold motion from high-speed digital imaging, with a focus on developmental changes in vocal-fold kinematics during childhood. Vocal-fold vibrations were analyzed for 28 children (aged 5-11 years) and 28 adults (aged 21-45 years) without voice disorders. The following kinematic features were analyzed from the vocal-fold displacement waveforms: relative velocity-based features (normalized average and peak opening and closing velocities), relative acceleration-based features (normalized peak opening and closing accelerations), speed quotient, and normalized peak displacement. Children exhibited significantly larger normalized peak displacements, normalized average and peak opening velocities, normalized average and peak closing velocities, peak opening and closing accelerations, and speed quotient compared to adult women. Values of normalized average closing velocity and speed quotient were higher in children compared to adult men. When compared to adult men, developing children typically have higher estimates of kinematic features related to normalized displacement and its derivatives. In most cases, the kinematic features of children are closer to those of adult men than adult women. Even though boys experience greater changes in glottal length and pitch as they mature, results indicate that girls experience greater changes in kinematic features compared to boys.

Texture Feature Analysis for Different Resolution Level of Kidney Ultrasound Images

NASA Astrophysics Data System (ADS)

Kairuddin, Wan Nur Hafsha Wan; Mahmud, Wan Mahani Hafizah Wan

2017-08-01

Image feature extraction is a technique to identify the characteristic of the image. The objective of this work is to discover the texture features that best describe a tissue characteristic of a healthy kidney from ultrasound (US) image. Three ultrasound machines that have different specifications are used in order to get a different quality (different resolution) of the image. Initially, the acquired images are pre-processed to de-noise the speckle to ensure the image preserve the pixels in a region of interest (ROI) for further extraction. Gaussian Low- pass Filter is chosen as the filtering method in this work. 150 of enhanced images then are segmented by creating a foreground and background of image where the mask is created to eliminate some unwanted intensity values. Statistical based texture features method is used namely Intensity Histogram (IH), Gray-Level Co-Occurance Matrix (GLCM) and Gray-level run-length matrix (GLRLM).This method is depends on the spatial distribution of intensity values or gray levels in the kidney region. By using One-Way ANOVA in SPSS, the result indicated that three features (Contrast, Difference Variance and Inverse Difference Moment Normalized) from GLCM are not statistically significant; this concludes that these three features describe a healthy kidney characteristics regardless of the ultrasound image quality.

Self-esteem and other-esteem in college students with borderline and avoidant personality disorder features: An experimental vignette study.

PubMed

Bowles, David P; Armitage, Chris J; Drabble, Jennifer; Meyer, Björn

2013-11-01

An experimental study investigated self-esteem and other-esteem responses to either fully supportive or less supportive interpersonal feedback in college students with avoidant and borderline personality disorder features (APD and BPD respectively). Disturbances in self-esteem and in evaluations of others are central to definitions of both APD and BPD, but the extent to which such interpersonal appraisals are responsive to contextual features, such as evaluative feedback from others, is not yet clear. In theory, we would expect that individuals with pronounced PD features would show more inflexible and more negative self-evaluations and others- evaluations than those without PD features. In this study with 169 undergraduates, APD but not BPD features were associated with other-contingent state self-esteem and other-esteem. A significant interaction indicated that highly avoidant respondents felt particularly negatively about themselves and their close others in situations that conveyed subtle criticism but not in situations signalling unequivocal support. This suggests that their self-esteem and other-esteem, rather than being rigidly negative, are instead highly contingent upon interpersonal feedback. Such context contingency has implications for the trait-like description of diagnostic characteristics within current taxonomies and is in line with contemporary dynamic models of personality structure and process. Copyright © 2013 John Wiley & Sons, Ltd.

Classification of Microarray Data Using Kernel Fuzzy Inference System

PubMed Central

Kumar Rath, Santanu

2014-01-01

The DNA microarray classification technique has gained more popularity in both research and practice. In real data analysis, such as microarray data, the dataset contains a huge number of insignificant and irrelevant features that tend to lose useful information. Classes with high relevance and feature sets with high significance are generally referred for the selected features, which determine the samples classification into their respective classes. In this paper, kernel fuzzy inference system (K-FIS) algorithm is applied to classify the microarray data (leukemia) using t-test as a feature selection method. Kernel functions are used to map original data points into a higher-dimensional (possibly infinite-dimensional) feature space defined by a (usually nonlinear) function ϕ through a mathematical process called the kernel trick. This paper also presents a comparative study for classification using K-FIS along with support vector machine (SVM) for different set of features (genes). Performance parameters available in the literature such as precision, recall, specificity, F-measure, ROC curve, and accuracy are considered to analyze the efficiency of the classification model. From the proposed approach, it is apparent that K-FIS model obtains similar results when compared with SVM model. This is an indication that the proposed approach relies on kernel function. PMID:27433543

Borderline Personality Features, Anger, and Intimate Partner Violence: An Experimental Manipulation of Rejection.

PubMed

Armenti, Nicholas A; Babcock, Julia C

2018-04-01

Individuals with borderline personality features may be susceptible to react to situational stressors with negative and interpersonally maladaptive emotionality (e.g., anger) and aggression. The current study attempted to test two moderated mediation models to investigate dispositional risk factors associated with borderline personality features and intimate partner violence (IPV). Results from an experimental rejection induction paradigm were examined using moderated regression to observe contextual reactions to imagined romantic rejection from a current romantic partner among individuals with borderline personality features. An ethnically diverse sample of 218 undergraduates at a large public university in the southwestern United States was recruited. Participants responded to demographic questions and self-report measures, and engaged in an experimental rejection induction paradigm. Borderline personality features was positively associated with rejection sensitivity, physical assault, and psychological aggression. Contrary to initial hypotheses, rejection sensitivity did not serve as a mediator of the relations between borderline personality features and physical assault and psychological aggression. However, trait anger mediated the relation between borderline personality features and psychological aggression. As such, trait anger may be an important explanatory variable in the relation between borderline personality features and psychological aggression specifically. Results of the rejection induction paradigm indicated that, for individuals who were asked to imagine an ambiguous rejection, the relation between borderline personality features and state anger post-rejection was strengthened. For individuals who imagined a critical rejection, there was no significant relation between borderline personality features and state anger post-rejection. Findings suggest that trait anger may be an important dispositional factor in the link between borderline personality features and IPV. In addition, contextual factors, such as ambiguous rejection by an intimate partner, may be especially relevant in activating anger or aggression in individuals with borderline personality features.

An exploration of subgroups of mild cognitive impairment based on cognitive, neuropsychiatric and functional features: analysis of data from the National Alzheimer's Coordinating Center.

PubMed

Hanfelt, John J; Wuu, Joanne; Sollinger, Ann B; Greenaway, Melanie C; Lah, James J; Levey, Allan I; Goldstein, Felicia C

2011-11-01

To empirically expand the existing subtypes of mild cognitive impairment (MCI) by incorporating information on neuropsychiatric and functional features, and to assess whether cerebrovascular disease (CVD) risk factors are associated with any of these subgroups. Latent class analysis using 1,655 patients with MCI. Participants in the Uniform Data Set (UDS) from 29 National Institutes of Health-supported Alzheimer's Disease Centers. Patients with a consensus diagnosis of MCI from each center and with a Mini-Mental State Examination score of 22 or greater. UDS cognitive battery, Neuropsychiatric Inventory Questionnaire, and Functional Assessment Questionnaire administered at initial visit. Seven empirically based subgroups of MCI were identified: 1) minimally impaired (relative frequency, 12%); 2) amnestic only (16%); 3) amnestic with functional and neuropsychiatric features (16%); 4) amnestic multidomain (12%); 5) amnestic multidomain with functional and neuropsychiatric features (12%); 6) functional and neuropsychiatric features (15%); and 7) executive function and language impairments (18%). Two of these subgroups with functional and neuropsychiatric features were at least 3.8 times more likely than the minimally impaired subgroup to have a Rosen-Hachinski score of 4 or greater, an indicator of probable CVD. Findings suggest that there are several distinct phenotypes of MCI characterized by prominent cognitive features, prominent functional features, and neuropsychiatric features or a combination of all three. Subgroups with functional and neuropsychiatric features are significantly more likely to have CVD, which suggests that there may be distinct differences in disease etiology from the other phenotypes.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pasyanos, M

We study the lithospheric structure of Africa, Arabia and adjacent oceanic regions with fundamental-mode surface waves over a wide period range. Including short period group velocities allows us to examine shallower features than previous studies of the whole continent. In the process, we have developed a crustal thickness map of Africa. Main features include crustal thickness increases under the West African, Congo, and Kalahari cratons. We find crustal thinning under Mesozoic and Cenozoic rifts, including the Benue Trough, Red Sea, and East, Central, and West African rift systems. Crustal shear wave velocities are generally faster in oceanic regions and cratons,more » and slower in more recent crust and in active and formerly active orogenic regions. Deeper structure, related to the thickness of cratons and modern rifting, is generally consistent with previous work. Under cratons we find thick lithosphere and fast upper mantle velocities, while under rifts we find thinned lithosphere and slower upper mantle velocities. There are no consistent effects in areas classified as hotspots, indicating that there seem to be numerous origins for these features. Finally, it appears that the African Superswell has had a significantly different impact in the north and the south, indicating specifics of the feature (temperature, time of influence, etc.) to be dissimilar between the two regions. Factoring in other information, it is likely that the southern portion has been active in the past, but that shallow activity is currently limited to the northern portion of the superswell.« less

A Multi Agent System for Flow-Based Intrusion Detection

DTIC Science & Technology

2013-03-01

Student t-test, as it is less likely to spuriously indicate significance because of the presence of outliers [128]. We use the MATLAB ranksum function [77...effectiveness of self-organization and “ entangled hierarchies” for accomplishing scenario objectives. One of the interesting features of SOMAS is the ability...cross-validation and automatic model selection. It has interfaces for Java, Python, R, Splus, MATLAB , Perl, Ruby, and LabVIEW. Kernels: linear

Memristor-integrated voltage-stabilizing supercapacitor system.

PubMed

Liu, Bin; Liu, Boyang; Wang, Xianfu; Wu, Xinghui; Zhao, Wenning; Xu, Zhimou; Chen, Di; Shen, Guozhen

2014-08-06

Voltage-stabilized supercapacitors: A single supercapacitor formed with PCBM/Pt/IPS nanorod-array electrodes is designed and delivers enhanced areal capacitance, capacitance retention, and excellent electrical stability under bending, while a significant voltage-decrease is observed during the discharging process. Once integrated with the memristor, the memristor-integrated supercapacitor systems deliver an extremely low voltage-drop, indicating greatly enhanced voltage-stabilizing features. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Periocular hemangiomas: what every physician should know.

PubMed

Ceisler, Emily J; Santos, Laura; Blei, Francine

2004-01-01

Hemangiomas are the most common benign tumor of infancy. Most hemangiomas remain asymptomatic and can be managed by close observation; however, immediate treatment is indicated for hemangiomas that may cause significant complications. Periocular hemangiomas warrant close evaluation and early, active treatment of those with the potential to threaten or permanently compromise vision. Herein we review the clinical features of periocular hemangiomas, differential diagnosis, possible ophthalmologic complications and sequelae, and therapeutic modalities.

Engineering geologic and geotechnical analysis of paleoseismic shaking using liquefaction effects: Field examples

USGS Publications Warehouse

Green, R.A.; Obermeier, S.F.; Olson, S.M.

2005-01-01

The greatest impediments to the widespread acceptance of back-calculated ground motion characteristics from paleoliquefaction studies typically stem from three uncertainties: (1) the significance of changes in the geotechnical properties of post-liquefied sediments (e.g., "aging" and density changes), (2) the selection of appropriate geotechnical soil indices from individual paleoliquefaction sites, and (3) the methodology for integration of back-calculated results of strength of shaking from individual paleoliquefaction sites into a regional assessment of paleoseismic strength of shaking. Presented herein are two case studies that illustrate the methods outlined by Olson et al. [Engineering Geology, this issue] for addressing these uncertainties. The first case study is for a site near Memphis, Tennessee, wherein cone penetration test data from side-by-side locations, one of liquefaction and the other of no liquefaction, are used to readily discern that the influence of post-liquefaction "aging" and density changes on the measured in situ soil indices is minimal. In the second case study, 12 sites that are at scattered locations in the Wabash Valley and that exhibit paleoliquefaction features are analyzed. The features are first provisionally attributed to the Vincennes Earthquake, which occurred around 6100 years BP, and are used to illustrate our proposed approach for selecting representative soil indices of the liquefied sediments. These indices are used in back-calculating the strength of shaking at the individual sites, the results from which are then incorporated into a regional assessment of the moment magnitude, M, of the Vincennes Earthquake. The regional assessment validated the provisional assumption that the paleoliquefaction features at the scattered sites were induced by the Vincennes Earthquake, in the main, which was determined to have M ??? 7.5. The uncertainties and assumptions used in the assessment are discussed in detail. ?? 2004 Elsevier B.V. All rights reserved.

Evaluating Heavy Metal Stress Levels in Rice Based on Remote Sensing Phenology.

PubMed

Liu, Tianjiao; Liu, Xiangnan; Liu, Meiling; Wu, Ling

2018-03-14

Heavy metal pollution of croplands is a major environmental problem worldwide. Methods for accurately and quickly monitoring heavy metal stress have important practical significance. Many studies have explored heavy metal stress in rice in relation to physiological function or physiological factors, but few studies have considered phenology, which can be sensitive to heavy metal stress. In this study, we used an integrated Normalized Difference Vegetation Index (NDVI) time-series image set to extract remote sensing phenology. A phenological indicator relatively sensitive to heavy metal stress was chosen from the obtained phenological periods and phenological parameters. The Dry Weight of Roots (WRT), which directly affected by heavy metal stress, was simulated by the World Food Study (WOFOST) model; then, a feature space based on the phenological indicator and WRT was established for monitoring heavy metal stress. The results indicated that the feature space can distinguish the heavy metal stress levels in rice, with accuracy greater than 95% for distinguishing the severe stress level. This finding provides scientific evidence for combining rice phenology and physiological characteristics in time and space, and the method is useful to monitor heavy metal stress in rice.

The ultrastructural features of the premalignant oral lesions.

PubMed

Olinici, Doiniţa; Cotrutz, Carmen Elena; Mihali, Ciprian Valentin; Grecu, Vasile Bogdan; Botez, Emanuela Ana; Stoica, Laura; Onofrei, Pavel; Condurache, Oana; Dimitriu, Daniela Cristina

2018-01-01

Premalignant oral lesions are among the most important risk factors for the development of oral squamocellular carcinoma. Recent population studies indicate a significant rise in the prevalence of leukoplakia, erythroplakia/erythroleukoplakia, actinic cheilitis, submucous fibrosis and erosive lichen planus. Since standard histopathological examination has numerous limitations regarding the accurate appreciation of potential malignant transformation, the present study aims to aid these evaluations using the transmission electron microscopy (TEM) technique, which emphasizes ultrastructural changes pertaining to this pathology. Oral mucosa fragments collected from 43 patients that were clinically and histopathologically diagnosed with leukoplakia, erosive actinic cheilitis and erosive lichen planus have been processed through the classic technique for the examination using TEM and were examined using a Philips CM100 transmission electron microscope. The electron microscopy study has confirmed the histopathological diagnosis of the tissue samples examined using photonic microscopy and has furthermore revealed a series of ultrastructural details that on the one hand indicate the tendency for malignant transformation, and on the other reveal characteristic features of tumor development. All the details furnished by TEM complete the overall picture of morphological changes, specific to these lesions, indicating the importance of using these techniques in establishing both a correct diagnosis and prognosis.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Syracuse, E. M.; Maceira, M.; Zhang, H.

Joint inversions of seismic data recover models that simultaneously fit multiple constraints while playing upon the strengths of each data type. Here, we jointly invert 14 years of local earthquake body wave arrival times from the Alaska Volcano Observatory catalog and Rayleigh wave dispersion curves based upon ambient noise measurements for local V p, V s, and hypocentral locations at Akutan and Makushin Volcanoes using a new joint inversion algorithm.The velocity structure and relocated seismicity of both volcanoes are significantly more complex than many other volcanoes studied using similar techniques. Seismicity is distributed among several areas beneath or beyond themore » flanks of both volcanoes, illuminating a variety of volcanic and tectonic features. The velocity structures of the two volcanoes are exemplified by the presence of narrow high-V p features in the near surface, indicating likely current or remnant pathways of magma to the surface. A single broad low-V p region beneath each volcano is slightly offset from each summit and centered at approximately 7 km depth, indicating a potential magma chamber, where magma is stored over longer time periods. Differing recovery capabilities of the Vp and Vs datasets indicate that the results of these types of joint inversions must be interpreted carefully.« less

Multivariate analysis of full-term neonatal polysomnographic data.

PubMed

Gerla, V; Paul, K; Lhotska, L; Krajca, V

2009-01-01

Polysomnography (PSG) is one of the most important noninvasive methods for studying maturation of the child brain. Sleep in infants is significantly different from sleep in adults. This paper addresses the problem of computer analysis of neonatal polygraphic signals. We applied methods designed for differentiating three important neonatal behavioral states: quiet sleep, active sleep, and wakefulness. The proportion of these states is a significant indicator of the maturity of the newborn brain in clinical practice. In this study, we used data provided by the Institute for Care of Mother and Child, Prague (12 newborn infants of similar postconceptional age). The data were scored by an experienced physician to four states (wake, quiet sleep, active sleep, movement artifact). For accurate classification, it was necessary to determine the most informative features. We used a method based on power spectral density (PSD) applied to each EEG channel. We also used features derived from electrooculogram (EOG), electromyogram (EMG), ECG, and respiration [pneumogram (PNG)] signals. The most informative feature was the measure of regularity of respiration from the PNG signal. We designed an algorithm for interpreting these characteristics. This algorithm was based on Markov models. The results of automatic detection of sleep states were compared to the "sleep profiles" determined visually. We evaluated both the success rate and the true positive rate of the classification, and statistically significant agreement of the two scorings was found. Two variants, for learning and for testing, were applied, namely learning from the data of all 12 newborns and tenfold cross-validation, and learning from the data of 11 newborns and testing on the data from the 12th newborn. We utilized information obtained from several biological signals (EEG, ECG, PNG, EMG, EOG) for our final classification. We reached the final success rate of 82.5%. The true positive rate was 81.8% and the false positive rate was 6.1%. The most important step in the whole process is feature extraction and feature selection. In this process, we used visualization as an additional tool that helped us to decide which features to select. Proper selection of features may significantly influence the success rate of the classification. We made a visual comparison of the computed features with the manual scoring provided by the expert. A hidden Markov model was used for classification. The advantage of this model is that it determines the future behavior of the process by its present state. In this way, it preserves information about temporal development.

Left nucleus accumbens atrophy in deficit schizophrenia: A preliminary study.

PubMed

De Rossi, Pietro; Dacquino, Claudia; Piras, Fabrizio; Caltagirone, Carlo; Spalletta, Gianfranco

2016-08-30

A question that remains to be answered is whether schizophrenia can be characterized by a single etiopathophysiology or whether separate sub-syndromes should be differentiated to define specific mechanisms for each sub-type. Individuals affected by the deficit subtype of schizophrenia (DSZ) display avolitional/amotivational features that respond poorly to conventional treatments. Characterizing DSZ from a neuroanatomical point of view may help clarify this issue and develop new treatment strategies. To determine if DSZ is associated with structural alterations in specific deep grey matter structures linked to its key clinical features, 22 DSZ patients, 22 non-deficit schizophrenia (NDSZ) patients and 22 healthy controls (HC) were recruited for a case-control cross-sectional study. High-resolution magnetic resonance imaging was performed in all subjects and volumes of deep grey matter structures were measured using FreeSurfer. DSZ patients displayed smaller left accumbens volumes compared to both NDSZ patients and HC. Moreover, age and duration of illness were significantly associated with lower volume of the left accumbens in DSZ but not in NDSZ. Findings indicate that DSZ is associated with lower volume of the nucleus accumbens in the dominant hemisphere. This is consistent with the psychopathological features and functional impairments present in DSZ and thus indicates a potential mechanism. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Investigation of relationships between linears, total and hazy areas, and petroleum production in the Williston Basin: An ERTS approach

NASA Technical Reports Server (NTRS)

Erickson, J. M.; Street, J. S. (Principal Investigator); Munsell, C. J.; Obrien, D. E.

1975-01-01

The author has identified the following significant results. ERTS-1 imagery in a variety of formats was used to locate linear, tonal, and hazy features and to relate them to areas of hydrocarbon production in the Williston Basin of North Dakota, eastern Montana, and northern South Dakota. Derivative maps of rectilinear, curvilinear, tonal, and hazy features were made using standard laboratory techniques. Mapping of rectilinears on both bands 5 and 7 over the entire region indicated the presence of a northeast-southwest and a northwest-southeast regional trend which is indicative of the bedrock fracture pattern in the basin. Curved lines generally bound areas of unique tone, maps of tonal patterns repeat many of the boundaries seen on curvilinear maps. Tones were best analyzed on spring and fall imagery in the Williston Basin. It is postulated that hazy areas are caused by atmospheric phenomena. The ability to use ERTS imagery as an exploration tool was examined where petroleum and gas are presently produced (Bottineau Field, Nesson and Antelope anticlines, Redwing Creek, and Cedar Creek anticline). It is determined that some tonal and linear features coincide with location of present production in Redwing and Cedar Creeks. In the remaining cases, targets could not be sufficiently well defined to justify this method.

Flow Around a Crater on Ceres

NASA Image and Video Library

2017-05-02

Ceres surface shows evidence for different types of flows that indicate the presence of ice in the regolith. One type of flow encircles the large impact crater at right in this image taken by NASA Dawn spacecraft. One type of flow encircles the large impact crater at right in this image. Scientists see features in this flow that indicate a low degree of internal friction within its material, meaning it was able to flow easily and far from its source. This could be due to the incorporation of a significant amount of liquid water or water vapor into the ejecta blanket. This flow also shows a large ridge along its edge (seen most clearly just to the left of the large crater). These features are commonly associated with flows on Mars called "fluidized ejecta blankets." This feature is located southwest of Kerwan crater at 40 degrees south latitude, 109 degrees east longitude. This is in the vicinity of the latitudes where Dawn's gamma ray and neutron spectrometer (GRaND) instrument sensed the presence of ice in the first meter of Ceres' regolith. The image was taken on August, 7, 2016 from an altitude of about 240 miles (390 kilometers) above Ceres. The image resolution is about 120 feet (35 meters) per pixel. https://photojournal.jpl.nasa.gov/catalog/PIA21404

Influence of habitat heterogeneity on distribution, occupancy patterns, and productivity of breeding peregrine falcons in central west Greenland

USGS Publications Warehouse

Wightman, C.; Fuller, Mark R.

2006-01-01

We used occupancy and productivity data collected at 67 cliffs used for nesting from 1972 to 1999 to assess patterns of distribution and nest-site selection in an increasing population of Peregrine Falcons (Falco peregrinus) in central West Greenland. Peregrine Falcons breeding at traditionally occupied cliffs used for nesting had significantly lower variation in productivity and thus these cliffs were better quality sites. This indicates that Peregrine Falcons occupied cliffs according to a pattern of despotic distribution. Falcons breeding at cliffs that were consistently occupied during the breeding season had higher average productivity and lower variation in productivity than falcons at inconsistently occupied cliffs, and thus consistent occupancy also was indicative of cliff quality. Features of high quality habitat included tall cliffs, greater change in elevation from the lowest point within 3 km of the cliff to the cliff top (elevation gain), and protection from weather on the eyrie ledge. Spacing of suitable and occupied cliffs also was an important feature, and the best cliffs generally were more isolated. Increased spacing was likely a mechanism for reducing intraspecific competition. Our results suggest that Peregrine Falcons use a resource defense strategy to compete for better quality habitats and may use spacing and physical features of a nest site to identify good quality breeding habitat.

The effect of recording site on extracted features of motor unit action potential.

PubMed

Artuğ, N Tuğrul; Goker, Imran; Bolat, Bülent; Osman, Onur; Kocasoy Orhan, Elif; Baslo, M Baris

2016-06-01

Motor unit action potential (MUAP), which consists of individual muscle fiber action potentials (MFAPs), represents the electrical activity of the motor unit. The values of the MUAP features are changed by denervation and reinnervation in neurogenic involvement as well as muscle fiber loss with increased diameter variability in myopathic diseases. The present study is designed to investigate how increased muscle fiber diameter variability affects MUAP parameters in simulated motor units. In order to detect this variation, simulated MUAPs were calculated both at the innervation zone where the MFAPs are more synchronized, and near the tendon, where they show increased temporal dispersion. Reinnervation in neurogenic state increases MUAP amplitude for the recordings at both the innervation zone and near the tendon. However, MUAP duration and the number of peaks significantly increased in a case of myopathy for recordings near the tendon. Furthermore, of the new features, "number of peaks×spike duration" was found as the strongest indicator of MFAP dispersion in myopathy. MUAPs were also recorded from healthy participants in order to investigate the biological counterpart of the simulation data. MUAPs which were recorded near to tendon revealed significantly prolonged duration and decreased amplitude. Although the number of peaks was increased by moving the needle near to tendon, this was not significant. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Assessment of seasonal features based on Landsat time series for tree crown cover mapping in Burkina Faso

NASA Astrophysics Data System (ADS)

Liu, Jinxiu; Heiskanen, Janne; Aynekuly, Ermias; Pellikka, Petri

2016-04-01

Tree crown cover (CC) is an important vegetation attribute for land cover characterization, and for mapping and monitoring forest cover. Free data from Landsat and Sentinel-2 allow construction of fine resolution satellite image time series and extraction of seasonal features for predicting vegetation attributes. In the savannas, surface reflectance vary distinctively according to the rainy and dry seasons, and seasonal features are useful information for CC mapping. However, it is unclear if it is better to use spectral bands or vegetation indices (VI) for computation of seasonal features, and how feasible different VI are for CC prediction in the savanna woodlands and agroforestry parklands of West Africa. In this study, the objective was to compare seasonal features based on spectral bands and VI for CC mapping in southern Burkina Faso. A total of 35 Landsat images from November 2013 to October 2014 were processed. Seasonal features were computed using a harmonic model with three parameters (mean, amplitude and phase), and spectral bands, normalized difference vegetation index (NDVI), green normalized difference vegetation index (GNDVI), normalized difference water index (NDWI), tasseled cap (TC) indices (brightness, greenness, wetness) as input data. The seasonal features were employed to predict field estimated CC (n = 160) using Random Forest algorithm. The most accurate results were achieved when using seasonal features based on TC indices (R2: 0.65; RMSE: 10.7%) and spectral bands (R2: 0.64; RMSE: 10.8%). GNDVI performed better than NDVI or NDWI, and NDWI resulted in the poorest results (R2: 0.56; RMSE: 11.9%). The results indicate that spectral features should be carefully selected for CC prediction as shown by relatively poor performance of commonly used NDVI. The seasonal features based on three TC indices and all the spectral bands provided superior accuracy in comparison to single VI. The method presented in this study provides a feasible method to map CC based on seasonal features with possibility to integrate medium resolution satellite observation from several sensors (e.g. Landsat and Sentinel-2) in the future.

An automated decision-tree approach to predicting protein interaction hot spots.

PubMed

Darnell, Steven J; Page, David; Mitchell, Julie C

2007-09-01

Protein-protein interactions can be altered by mutating one or more "hot spots," the subset of residues that account for most of the interface's binding free energy. The identification of hot spots requires a significant experimental effort, highlighting the practical value of hot spot predictions. We present two knowledge-based models that improve the ability to predict hot spots: K-FADE uses shape specificity features calculated by the Fast Atomic Density Evaluation (FADE) program, and K-CON uses biochemical contact features. The combined K-FADE/CON (KFC) model displays better overall predictive accuracy than computational alanine scanning (Robetta-Ala). In addition, because these methods predict different subsets of known hot spots, a large and significant increase in accuracy is achieved by combining KFC and Robetta-Ala. The KFC analysis is applied to the calmodulin (CaM)/smooth muscle myosin light chain kinase (smMLCK) interface, and to the bone morphogenetic protein-2 (BMP-2)/BMP receptor-type I (BMPR-IA) interface. The results indicate a strong correlation between KFC hot spot predictions and mutations that significantly reduce the binding affinity of the interface. 2007 Wiley-Liss, Inc.

Diagnostic and prognostic value of amyloid PET textural and shape features: comparison with classical semi-quantitative rating in 760 patients from the ADNI-2 database.

PubMed

Ben Bouallègue, Fayçal; Vauchot, Fabien; Mariano-Goulart, Denis; Payoux, Pierre

2018-02-09

We evaluated the performance of amyloid PET textural and shape features in discriminating normal and Alzheimer's disease (AD) subjects, and in predicting conversion to AD in subjects with mild cognitive impairment (MCI) or significant memory concern (SMC). Subjects from the Alzheimer's Disease Neuroimaging Initiative with available baseline 18 F-florbetapir and T1-MRI scans were included. The cross-sectional cohort consisted of 181 controls and 148 AD subjects. The longitudinal cohort consisted of 431 SMC/MCI subjects, 85 of whom converted to AD during follow-up. PET images were normalized to MNI space and post-processed using in-house software. Relative retention indices (SUVr) were computed with respect to pontine, cerebellar, and composite reference regions. Several textural and shape features were extracted then combined using a support vector machine (SVM) to build a predictive model of AD conversion. Diagnostic and prognostic performance was evaluated using ROC analysis and survival analysis with the Cox proportional hazard model. The three SUVr and all the tested features effectively discriminated AD subjects in cross-sectional analysis (all p < 0.001). In longitudinal analysis, the variables with the highest prognostic value were composite SUVr (AUC 0.86; accuracy 81%), skewness (0.87; 83%), local minima (0.85; 79%), Geary's index (0.86; 81%), gradient norm maximal argument (0.83; 82%), and the SVM model (0.91; 86%). The adjusted hazard ratio for AD conversion was 5.5 for the SVM model, compared with 4.0, 2.6, and 3.8 for cerebellar, pontine and composite SUVr (all p < 0.001), indicating that appropriate amyloid textural and shape features predict conversion to AD with at least as good accuracy as classical SUVr.

Coupled binary embedding for large-scale image retrieval.

PubMed

Zheng, Liang; Wang, Shengjin; Tian, Qi

2014-08-01

Visual matching is a crucial step in image retrieval based on the bag-of-words (BoW) model. In the baseline method, two keypoints are considered as a matching pair if their SIFT descriptors are quantized to the same visual word. However, the SIFT visual word has two limitations. First, it loses most of its discriminative power during quantization. Second, SIFT only describes the local texture feature. Both drawbacks impair the discriminative power of the BoW model and lead to false positive matches. To tackle this problem, this paper proposes to embed multiple binary features at indexing level. To model correlation between features, a multi-IDF scheme is introduced, through which different binary features are coupled into the inverted file. We show that matching verification methods based on binary features, such as Hamming embedding, can be effectively incorporated in our framework. As an extension, we explore the fusion of binary color feature into image retrieval. The joint integration of the SIFT visual word and binary features greatly enhances the precision of visual matching, reducing the impact of false positive matches. Our method is evaluated through extensive experiments on four benchmark datasets (Ukbench, Holidays, DupImage, and MIR Flickr 1M). We show that our method significantly improves the baseline approach. In addition, large-scale experiments indicate that the proposed method requires acceptable memory usage and query time compared with other approaches. Further, when global color feature is integrated, our method yields competitive performance with the state-of-the-arts.

Face detection on distorted images using perceptual quality-aware features

NASA Astrophysics Data System (ADS)

Gunasekar, Suriya; Ghosh, Joydeep; Bovik, Alan C.

2014-02-01

We quantify the degradation in performance of a popular and effective face detector when human-perceived image quality is degraded by distortions due to additive white gaussian noise, gaussian blur or JPEG compression. It is observed that, within a certain range of perceived image quality, a modest increase in image quality can drastically improve face detection performance. These results can be used to guide resource or bandwidth allocation in a communication/delivery system that is associated with face detection tasks. A new face detector based on QualHOG features is also proposed that augments face-indicative HOG features with perceptual quality-aware spatial Natural Scene Statistics (NSS) features, yielding improved tolerance against image distortions. The new detector provides statistically significant improvements over a strong baseline on a large database of face images representing a wide range of distortions. To facilitate this study, we created a new Distorted Face Database, containing face and non-face patches from images impaired by a variety of common distortion types and levels. This new dataset is available for download and further experimentation at www.ideal.ece.utexas.edu/˜suriya/DFD/.

Correlated Topic Vector for Scene Classification.

PubMed

Wei, Pengxu; Qin, Fei; Wan, Fang; Zhu, Yi; Jiao, Jianbin; Ye, Qixiang

2017-07-01

Scene images usually involve semantic correlations, particularly when considering large-scale image data sets. This paper proposes a novel generative image representation, correlated topic vector, to model such semantic correlations. Oriented from the correlated topic model, correlated topic vector intends to naturally utilize the correlations among topics, which are seldom considered in the conventional feature encoding, e.g., Fisher vector, but do exist in scene images. It is expected that the involvement of correlations can increase the discriminative capability of the learned generative model and consequently improve the recognition accuracy. Incorporated with the Fisher kernel method, correlated topic vector inherits the advantages of Fisher vector. The contributions to the topics of visual words have been further employed by incorporating the Fisher kernel framework to indicate the differences among scenes. Combined with the deep convolutional neural network (CNN) features and Gibbs sampling solution, correlated topic vector shows great potential when processing large-scale and complex scene image data sets. Experiments on two scene image data sets demonstrate that correlated topic vector improves significantly the deep CNN features, and outperforms existing Fisher kernel-based features.

Combining functional and structural tests improves the diagnostic accuracy of relevance vector machine classifiers

PubMed Central

Racette, Lyne; Chiou, Christine Y.; Hao, Jiucang; Bowd, Christopher; Goldbaum, Michael H.; Zangwill, Linda M.; Lee, Te-Won; Weinreb, Robert N.; Sample, Pamela A.

2009-01-01

Purpose To investigate whether combining optic disc topography and short-wavelength automated perimetry (SWAP) data improves the diagnostic accuracy of relevance vector machine (RVM) classifiers for detecting glaucomatous eyes compared to using each test alone. Methods One eye of 144 glaucoma patients and 68 healthy controls from the Diagnostic Innovations in Glaucoma Study were included. RVM were trained and tested with cross-validation on optimized (backward elimination) SWAP features (thresholds plus age; pattern deviation (PD); total deviation (TD)) and on Heidelberg Retina Tomograph II (HRT) optic disc topography features, independently and in combination. RVM performance was also compared to two HRT linear discriminant functions (LDF) and to SWAP mean deviation (MD) and pattern standard deviation (PSD). Classifier performance was measured by the area under the receiver operating characteristic curves (AUROCs) generated for each feature set and by the sensitivities at set specificities of 75%, 90% and 96%. Results RVM trained on combined HRT and SWAP thresholds plus age had significantly higher AUROC (0.93) than RVM trained on HRT (0.88) and SWAP (0.76) alone. AUROCs for the SWAP global indices (MD: 0.68; PSD: 0.72) offered no advantage over SWAP thresholds plus age, while the LDF AUROCs were significantly lower than RVM trained on the combined SWAP and HRT feature set and on HRT alone feature set. Conclusions Training RVM on combined optimized HRT and SWAP data improved diagnostic accuracy compared to training on SWAP and HRT parameters alone. Future research may identify other combinations of tests and classifiers that can also improve diagnostic accuracy. PMID:19528827

Expression of HIWI in human esophageal squamous cell carcinoma is significantly associated with poorer prognosis

PubMed Central

2009-01-01

Background HIWI, the human homologue of Piwi family, is present in CD34+ hematopoietic stem cells and germ cells, but not in well-differentiated cell populations, indicating that HIWI may play an impotent role in determining or maintaining stemness of these cells. That HIWI expression has been detected in several type tumours may suggest its association with clinical outcome in cancer patients. Methods With the methods of real-time PCR, western blot, immunocytochemistry and immunohistochemistry, the expression of HIWI in three esophageal squamous cancer cell lines KYSE70, KYSE140 and KYSE450 has been characterized. Then, we investigated HIWI expression in a series of 153 esophageal squamous cell carcinomas using immunohistochemistry and explored its association with clinicopathological features. Results The expression of HIWI was observed in tumour cell nuclei or/and cytoplasm in 137 (89.5%) cases, 16 (10.5%) cases were negative in both nuclei and cytoplasm. 86 (56.2%) were strongly positive in cytoplasm, while 49 (32.0%) were strongly positive in nuclei. The expression level of HIWI in cytoplasm of esophageal cancer cells was significantly associated with histological grade (P = 0.011), T stage (P = 0.035), and clinic outcome (P < 0.001), while there was no correlation between the nuclear HIWI expression and clinicopathological features. Conclusion The expression of HIWI in the cytoplasm of esophageal cancer cells is significantly associated with higher histological grade, clinical stage and poorer clinical outcome, indicating its possible involvement in cancer development. PMID:19995427

Visual Prediction Error Spreads Across Object Features in Human Visual Cortex

PubMed Central

Summerfield, Christopher; Egner, Tobias

2016-01-01

Visual cognition is thought to rely heavily on contextual expectations. Accordingly, previous studies have revealed distinct neural signatures for expected versus unexpected stimuli in visual cortex. However, it is presently unknown how the brain combines multiple concurrent stimulus expectations such as those we have for different features of a familiar object. To understand how an unexpected object feature affects the simultaneous processing of other expected feature(s), we combined human fMRI with a task that independently manipulated expectations for color and motion features of moving-dot stimuli. Behavioral data and neural signals from visual cortex were then interrogated to adjudicate between three possible ways in which prediction error (surprise) in the processing of one feature might affect the concurrent processing of another, expected feature: (1) feature processing may be independent; (2) surprise might “spread” from the unexpected to the expected feature, rendering the entire object unexpected; or (3) pairing a surprising feature with an expected feature might promote the inference that the two features are not in fact part of the same object. To formalize these rival hypotheses, we implemented them in a simple computational model of multifeature expectations. Across a range of analyses, behavior and visual neural signals consistently supported a model that assumes a mixing of prediction error signals across features: surprise in one object feature spreads to its other feature(s), thus rendering the entire object unexpected. These results reveal neurocomputational principles of multifeature expectations and indicate that objects are the unit of selection for predictive vision. SIGNIFICANCE STATEMENT We address a key question in predictive visual cognition: how does the brain combine multiple concurrent expectations for different features of a single object such as its color and motion trajectory? By combining a behavioral protocol that independently varies expectation of (and attention to) multiple object features with computational modeling and fMRI, we demonstrate that behavior and fMRI activity patterns in visual cortex are best accounted for by a model in which prediction error in one object feature spreads to other object features. These results demonstrate how predictive vision forms object-level expectations out of multiple independent features. PMID:27810936

Image processing for hazard recognition in on-board weather radar

NASA Technical Reports Server (NTRS)

Kelly, Wallace E. (Inventor); Rand, Timothy W. (Inventor); Uckun, Serdar (Inventor); Ruokangas, Corinne C. (Inventor)

2003-01-01

A method of providing weather radar images to a user includes obtaining radar image data corresponding to a weather radar image to be displayed. The radar image data is image processed to identify a feature of the weather radar image which is potentially indicative of a hazardous weather condition. The weather radar image is displayed to the user along with a notification of the existence of the feature which is potentially indicative of the hazardous weather condition. Notification can take the form of textual information regarding the feature, including feature type and proximity information. Notification can also take the form of visually highlighting the feature, for example by forming a visual border around the feature. Other forms of notification can also be used.

Vector computer memory bank contention

NASA Technical Reports Server (NTRS)

Bailey, D. H.

1985-01-01

A number of vector supercomputers feature very large memories. Unfortunately the large capacity memory chips that are used in these computers are much slower than the fast central processing unit (CPU) circuitry. As a result, memory bank reservation times (in CPU ticks) are much longer than on previous generations of computers. A consequence of these long reservation times is that memory bank contention is sharply increased, resulting in significantly lowered performance rates. The phenomenon of memory bank contention in vector computers is analyzed using both a Markov chain model and a Monte Carlo simulation program. The results of this analysis indicate that future generations of supercomputers must either employ much faster memory chips or else feature very large numbers of independent memory banks.

Smooth polishing of femtosecond laser induced craters on cemented carbide by ultrasonic vibration method

NASA Astrophysics Data System (ADS)

Wang, H. P.; Guan, Y. C.; Zheng, H. Y.

2017-12-01

Rough surface features induced by laser irradiation have been a challenging for the fabrication of micro/nano scale features. In this work, we propose hybrid ultrasonic vibration polishing method to improve surface quality of microcraters produced by femtosecond laser irradiation on cemented carbide. The laser caused rough surfaces are significantly smoothened after ultrasonic vibration polishing due to the strong collision effect of diamond particles on the surfaces. 3D morphology, SEM and AFM analysis has been conducted to characterize surface morphology and topography. Results indicate that the minimal surface roughness of Ra 7.60 nm has been achieved on the polished surfaces. The fabrication of microcraters with smooth surfaces is applicable to molding process for mass production of micro-optical components.

Hyperspectral imaging with wavelet transform for classification of colon tissue biopsy samples

NASA Astrophysics Data System (ADS)

Masood, Khalid

2008-08-01

Automatic classification of medical images is a part of our computerised medical imaging programme to support the pathologists in their diagnosis. Hyperspectral data has found its applications in medical imagery. Its usage is increasing significantly in biopsy analysis of medical images. In this paper, we present a histopathological analysis for the classification of colon biopsy samples into benign and malignant classes. The proposed study is based on comparison between 3D spectral/spatial analysis and 2D spatial analysis. Wavelet textural features in the wavelet domain are used in both these approaches for classification of colon biopsy samples. Experimental results indicate that the incorporation of wavelet textural features using a support vector machine, in 2D spatial analysis, achieve best classification accuracy.

The relationship between impulse control disorders and obsessive-compulsive disorder: a current understanding and future research directions

PubMed Central

Potenza, Marc Nicholas; Koran, Lorrin Michael; Pallanti, Stefano

2009-01-01

Impulse control disorders (ICDs) constitute a heterogeneous group of conditions linked diagnostically by difficulties in resisting “the impulse, drive, or temptation to perform an act that is harmful to the person or to others.” Specific ICDs share clinical, phenomenological and biological features with obsessive-compulsive disorder (OCD) that have suggested that these disorders might be categorized together. However, other data suggest significant differences between OCD and ICDs. In this article, clinical, phenomenological and biological features of the formal ICDs are reviewed and compared and contrasted with those of OCD. Available data indicate substantial differences between ICDs and OCD that suggest independent categorizations. Existing research gaps are identified and avenues for future research suggested. PMID:19811840

Airborne and groundbased spectrophotometry of comet P/Halley from 5-13 micrometers

NASA Technical Reports Server (NTRS)

Bregman, J. D.; Witteborn, F. C.; Allamandola, L. J.; Campins, H.; Wooden, D. H.; Rank, D. M.; Cohen, M.; Tielens, A. G. G. M.

1987-01-01

Spectrophotometry of comet Halley from 5-13 microns was obtained from the Kuiper Airborne Observatory and from the Lick Observatory Nickel Telescope, revealing a strong broad emission band at 10 microns and a weak feature at 6.8 microns. The 10-micron band is identified with silicate materials, and the primary component of the silicate emission is suggested to be due to olivine. The 6.8 micron feature may be due either to carbonates or the C-H deformation mode in organic molecules. The data indicate that small particles are abundant in the coma and that the dust contains at least two physically separate components. Significant spatial and temporal variations are also noted in the spectrum.

An application of locally linear model tree algorithm with combination of feature selection in credit scoring

NASA Astrophysics Data System (ADS)

Siami, Mohammad; Gholamian, Mohammad Reza; Basiri, Javad

2014-10-01

Nowadays, credit scoring is one of the most important topics in the banking sector. Credit scoring models have been widely used to facilitate the process of credit assessing. In this paper, an application of the locally linear model tree algorithm (LOLIMOT) was experimented to evaluate the superiority of its performance to predict the customer's credit status. The algorithm is improved with an aim of adjustment by credit scoring domain by means of data fusion and feature selection techniques. Two real world credit data sets - Australian and German - from UCI machine learning database were selected to demonstrate the performance of our new classifier. The analytical results indicate that the improved LOLIMOT significantly increase the prediction accuracy.

Polymyxins and quinazolines are LSD1/KDM1A inhibitors with unusual structural features.

PubMed

Speranzini, Valentina; Rotili, Dante; Ciossani, Giuseppe; Pilotto, Simona; Marrocco, Biagina; Forgione, Mariantonietta; Lucidi, Alessia; Forneris, Federico; Mehdipour, Parinaz; Velankar, Sameer; Mai, Antonello; Mattevi, Andrea

2016-09-01

Because of its involvement in the progression of several malignant tumors, the histone lysine-specific demethylase 1 (LSD1) has become a prominent drug target in modern medicinal chemistry research. We report on the discovery of two classes of noncovalent inhibitors displaying unique structural features. The antibiotics polymyxins bind at the entrance of the substrate cleft, where their highly charged cyclic moiety interacts with a cluster of positively charged amino acids. The same site is occupied by quinazoline-based compounds, which were found to inhibit the enzyme through a most peculiar mode because they form a pile of five to seven molecules that obstruct access to the active center. These data significantly indicate unpredictable strategies for the development of epigenetic inhibitors.

Vector computer memory bank contention

NASA Technical Reports Server (NTRS)

Bailey, David H.

1987-01-01

A number of vector supercomputers feature very large memories. Unfortunately the large capacity memory chips that are used in these computers are much slower than the fast central processing unit (CPU) circuitry. As a result, memory bank reservation times (in CPU ticks) are much longer than on previous generations of computers. A consequence of these long reservation times is that memory bank contention is sharply increased, resulting in significantly lowered performance rates. The phenomenon of memory bank contention in vector computers is analyzed using both a Markov chain model and a Monte Carlo simulation program. The results of this analysis indicate that future generations of supercomputers must either employ much faster memory chips or else feature very large numbers of independent memory banks.

A machine learning approach to identify functional biomarkers in human prefrontal cortex for individuals with traumatic brain injury using functional near-infrared spectroscopy.

PubMed

Karamzadeh, Nader; Amyot, Franck; Kenney, Kimbra; Anderson, Afrouz; Chowdhry, Fatima; Dashtestani, Hadis; Wassermann, Eric M; Chernomordik, Victor; Boccara, Claude; Wegman, Edward; Diaz-Arrastia, Ramon; Gandjbakhche, Amir H

2016-11-01

We have explored the potential prefrontal hemodynamic biomarkers to characterize subjects with Traumatic Brain Injury (TBI) by employing the multivariate machine learning approach and introducing a novel task-related hemodynamic response detection followed by a heuristic search for optimum set of hemodynamic features. To achieve this goal, the hemodynamic response from a group of 31 healthy controls and 30 chronic TBI subjects were recorded as they performed a complexity task. To determine the optimum hemodynamic features, we considered 11 features and their combinations in characterizing TBI subjects. We investigated the significance of the features by utilizing a machine learning classification algorithm to score all the possible combinations of features according to their predictive power. The identified optimum feature elements resulted in classification accuracy, sensitivity, and specificity of 85%, 85%, and 84%, respectively. Classification improvement was achieved for TBI subject classification through feature combination. It signified the major advantage of the multivariate analysis over the commonly used univariate analysis suggesting that the features that are individually irrelevant in characterizing the data may become relevant when used in combination. We also conducted a spatio-temporal classification to identify regions within the prefrontal cortex (PFC) that contribute in distinguishing between TBI and healthy subjects. As expected, Brodmann areas (BA) 10 within the PFC were isolated as the region that healthy subjects (unlike subjects with TBI), showed major hemodynamic activity in response to the High Complexity task. Overall, our results indicate that identified temporal and spatio-temporal features from PFC's hemodynamic activity are promising biomarkers in classifying subjects with TBI.

Content and Functionality of Alcohol and Other Drug Websites: Results of an Online Survey

PubMed Central

White, Angela; Kavanagh, David; Shandley, Kerrie; Kay-Lambkin, Frances; Proudfoot, Judith; Drennan, Judy; Connor, Jason; Baker, Amanda; Young, Ross

2010-01-01

Background There is a growing trend for individuals to seek health information from online sources. Alcohol and other drug (AOD) use is a significant health problem worldwide, but access and use of AOD websites is poorly understood. Objective To investigate content and functionality preferences for AOD and other health websites. Methods An anonymous online survey examined general Internet and AOD-specific usage and search behaviors, valued features of AOD and health-related websites (general and interactive website features), indicators of website trustworthiness, valued AOD website tools or functions, and treatment modality preferences. Results Surveys were obtained from 1214 drug (n = 766) and alcohol website users (n = 448) (mean age 26.2 years, range 16-70). There were no significant differences between alcohol and drug groups on demographic variables, Internet usage, indicators of website trustworthiness, or on preferences for AOD website functionality. A robust website design/navigation, open access, and validated content provision were highly valued by both groups. While attractiveness and pictures or graphics were also valued, high-cost features (videos, animations, games) were minority preferences. Almost half of respondents in both groups were unable to readily access the information they sought. Alcohol website users placed greater importance on several AOD website tools and functions than did those accessing other drug websites: online screening tools (χ²2 = 15.8, P < .001, n = 985); prevention programs (χ²2 = 27.5, P < .001, n = 981); tracking functions (χ²2 = 11.5, P = .003, n = 983); self help treatment programs (χ²2 = 8.3, P = .02, n = 984); downloadable fact sheets for friends (χ²2 = 11.6, P = .003, n = 981); or family (χ²2 = 12.7, P = .002, n = 983). The most preferred online treatment option for both the user groups was an Internet site with email therapist support. Explorations of demographic differences were also performed. While gender did not affect survey responses, younger respondents were more likely to value interactive and social networking features, whereas downloading of credible information was most highly valued by older respondents. Conclusions Significant deficiencies in the provision of accessible information on AOD websites were identified, an important problem since information seeking was the most common reason for accessing these websites, and, therefore, may be a key avenue for engaging website users in behaviour change. The few differences between AOD website users suggested that both types of websites may have similar features, although alcohol website users may more readily be engaged in screening, prevention and self-help programs, tracking change, and may value fact sheets more highly. While the sociodemographic differences require replication and clarification, these differences support the notion that the design and features of AOD websites should target specific audiences to have maximal impact. PMID:21169168

Intracranial EEG fluctuates over months after implanting electrodes in human brain

NASA Astrophysics Data System (ADS)

Ung, Hoameng; Baldassano, Steven N.; Bink, Hank; Krieger, Abba M.; Williams, Shawniqua; Vitale, Flavia; Wu, Chengyuan; Freestone, Dean; Nurse, Ewan; Leyde, Kent; Davis, Kathryn A.; Cook, Mark; Litt, Brian

2017-10-01

Objective. Implanting subdural and penetrating electrodes in the brain causes acute trauma and inflammation that affect intracranial electroencephalographic (iEEG) recordings. This behavior and its potential impact on clinical decision-making and algorithms for implanted devices have not been assessed in detail. In this study we aim to characterize the temporal and spatial variability of continuous, prolonged human iEEG recordings. Approach. Intracranial electroencephalography from 15 patients with drug-refractory epilepsy, each implanted with 16 subdural electrodes and continuously monitored for an average of 18 months, was included in this study. Time and spectral domain features were computed each day for each channel for the duration of each patient’s recording. Metrics to capture post-implantation feature changes and inflexion points were computed on group and individual levels. A linear mixed model was used to characterize transient group-level changes in feature values post-implantation and independent linear models were used to describe individual variability. Main results. A significant decline in features important to seizure detection and prediction algorithms (mean line length, energy, and half-wave), as well as mean power in the Berger and high gamma bands, was observed in many patients over 100 d following implantation. In addition, spatial variability across electrodes declines post-implantation following a similar timeframe. All selected features decreased by 14-50% in the initial 75 d of recording on the group level, and at least one feature demonstrated this pattern in 13 of the 15 patients. Our findings indicate that iEEG signal features demonstrate increased variability following implantation, most notably in the weeks immediately post-implant. Significance. These findings suggest that conclusions drawn from iEEG, both clinically and for research, should account for spatiotemporal signal variability and that properly assessing the iEEG in patients, depending upon the application, may require extended monitoring.

Dependence of RNA:DNA ratios and Fulton’s K condition indices on environmental characteristics of plaice and dab nursery grounds

NASA Astrophysics Data System (ADS)

De Raedemaecker, F.; Brophy, D.; O'Connor, I.; O'Neill, B.

2012-02-01

This field study showed a lack of a correlation between a morphometric (Fulton's K) and biochemical (RNA:DNA ratio) condition index in juvenile plaice ( Pleuronectes platessa) and dab ( Limanda limanda) studied to assess habitat quality in four sandy beach nursery grounds in Galway Bay, Ireland. Based on monthly surveys from June to September in 2008 and 2009, fish growth, indicated by RNA:DNA ratios and Fulton's K, displayed considerable spatio-temporal variability. Site-related patterns in Fulton's K for plaice and dab were consistent between years whereas RNA:DNA ratios displayed annual and interspecific variability among nursery habitats. This indicates a higher sensitivity of RNA:DNA ratios to short-term environmental fluctuations which is not apparent in Fulton's K measurements of juvenile flatfish. Generalized Additive Modelling (GAM) revealed non-linear relationships between the condition indices and (biotic and abiotic) habitat characteristics as well as diet features, derived from gut content analyses. Density of predators, sediment grain size and salinity were the most important predictors of both condition indices. Temperature also affected condition indices in dab whereas plaice condition indices varied with depth. Diet features did not contribute to the explained variability in the models predicting RNA:DNA ratios whereas certain prey groups significantly improved the explained variability in the models predicting Fulton's K of plaice and dab. The value of both indices for assessing fish condition and habitat quality in field studies is discussed. These findings aid understanding of the biological and physical mechanisms promoting fast growth and high survival which will help to identify high quality nursery areas for juvenile plaice and dab.

Promoting stair use: single versus multiple stair-riser messages.

PubMed

Webb, Oliver J; Eves, Frank F

2005-09-01

Message banners attached to stair risers produced a significant increase in pedestrian stair use, exceeding effects previously reported for conventional posters. Multiple instances of the same message banner, however, were as effective as banners featuring different messages. Therefore, greater visibility, rather than message variety, appears to account for the superiority of the banner format. Our findings indicate the feasibility of simple stair-use promotion campaigns based around the repetition of a single message.

Automated EEG sleep staging in the term-age baby using a generative modelling approach

NASA Astrophysics Data System (ADS)

Pillay, Kirubin; Dereymaeker, Anneleen; Jansen, Katrien; Naulaers, Gunnar; Van Huffel, Sabine; De Vos, Maarten

2018-06-01

Objective. We develop a method for automated four-state sleep classification of preterm and term-born babies at term-age of 38-40 weeks postmenstrual age (the age since the last menstrual cycle of the mother) using multichannel electroencephalogram (EEG) recordings. At this critical age, EEG differentiates from broader quiet sleep (QS) and active sleep (AS) stages to four, more complex states, and the quality and timing of this differentiation is indicative of the level of brain development. However, existing methods for automated sleep classification remain focussed only on QS and AS sleep classification. Approach. EEG features were calculated from 16 EEG recordings, in 30 s epochs, and personalized feature scaling used to correct for some of the inter-recording variability, by standardizing each recording’s feature data using its mean and standard deviation. Hidden Markov models (HMMs) and Gaussian mixture models (GMMs) were trained, with the HMM incorporating knowledge of the sleep state transition probabilities. Performance of the GMM and HMM (with and without scaling) were compared, and Cohen’s kappa agreement calculated between the estimates and clinicians’ visual labels. Main results. For four-state classification, the HMM proved superior to the GMM. With the inclusion of personalized feature scaling, mean kappa (±standard deviation) was 0.62 (±0.16) compared to the GMM value of 0.55 (±0.15). Without feature scaling, kappas for the HMM and GMM dropped to 0.56 (±0.18) and 0.51 (±0.15), respectively. Significance. This is the first study to present a successful method for the automated staging of four states in term-age sleep using multichannel EEG. Results suggested a benefit in incorporating transition information using an HMM, and correcting for inter-recording variability through personalized feature scaling. Determining the timing and quality of these states are indicative of developmental delays in both preterm and term-born babies that may lead to learning problems by school age.

Exploring the Time Evolution of Cool Metallic Absorption Features in UV Burst Spectra

NASA Astrophysics Data System (ADS)

Belmes, K.; Madsen, C. A.; DeLuca, E.

2017-12-01

UV bursts are compact brightenings in active regions that appear in UV images. They are identified through three spectroscopic features: (1) broadening and intensification of NUV/FUV emission lines, (2) the presence of optically thin Si IV emission, and (3) the presence of absorption features from cool metallic ions. Properties (2) and (3) imply that bursts exist at transition region temperatures (≥ 80,000 K) but are located in the cooler lower chromosphere ( 5,000 K). Their energetic and dynamical properties remain poorly constrained. Improving our understanding of this phenomena could help us further constrain the energetic and dynamical properties of the chromosphere, as well as give us insight into whether or not UV bursts contribute to chromospheric and/or coronal heating. We analyzed the time evolution of UV bursts using spectral data from the Interface Region Imaging Spectrograph (IRIS). We inspected Si IV 1393.8 Å line profiles for Ni II 1393.3 Å absorption features to look for signs of heating. Weakening of absorption features over time could indicate heating of the cool ions above the burst, implying that thermal energy from the burst could rapidly conduct upward through the chromosphere. To detect the spectral profiles corresponding to bursts, we applied a four-parameter Gaussian fit to every profile in each observation and took cuts in parameter space to isolate the bursts. We then manually reviewed the remaining profiles by looking for a statistically significant appearance of Ni II 1393.3 Å absorption. We quantified these absorption features by normalizing the Si IV 1393.8 Å emission profiles and measuring the maximum fractional extinction in each. Our preliminary results indicate that Ni II 1393.3 Å absorption may undergo a cycle of strengthening and weakening throughout a burst's lifetime. However, further investigation is needed for confirmation. This work is supported by the NSF-REU solar physics program at SAO, grant number AGS-1560313.

A comparative study of hematological parameters of α and β thalassemias in a high prevalence zone: Saudi Arabia

PubMed Central

Mehdi, Syed Riaz; Al Dahmash, Badr Abdullah

2011-01-01

BACKGROUND AND AIMS: Saudi Arabia falls in the high prevalent zone of αα and β thalassemias. Early screening for the type of thalassemia is essential for further investigations and management. The study was carried out to differentiate the type of thalassemia based on red cell indices and other hematological parameters. MATERIALS AND METHODS: The study was carried out on 991 clinically suspected cases of thalassemias in Riyadh, Saudi Arabia. The hematological parameters were studied on Coulter STKS. Cellulose acetate hemoglobin electrophoresis and high-performance liquid chromatography (HPLC) were performed on all the blood samples. Gene deletion studies were carried out by restriction fragment length polymorphism (RFLP) technique using the restriction endonucleases Bam HI. STATISTICAL ANALYSIS: Statistical analysis was performed on SPSS 11.5 version. RESULTS: The hemoglobin electrophoresis and gene studies revealed that there were 406 (40.96%) and 59 (5.95 %) cases of β thalassemia trait and β thalassemia major respectively including adults and children. 426 cases of various deletion forms of α thalassemias were seen. Microcytosis was a common feature in β thalassemias trait and (-α/-α) and (--/αα) types of α thalassemias. MCH was a more significant distinguishing feature among thalassemias. β thalassemia major and α thalassemia (-α/αα) had almost normal hematological parameters. CONCLUSION: MCV and RBC counts are not statistically significant features for discriminating between α and β thalassemias. There is need for development of a discrimination index to differentiate between α and β thalassemias traits on the lines of discriminatory Indices available for distinguishing β thalassemias trait from iron deficiency anemia. PMID:22345994

Sand ramps as palaeoenvironmental archives: Integrating general principles and regional contexts through reanalysis of the Klipkraal Sands, South Africa

NASA Astrophysics Data System (ADS)

Rowell, Alexandra L. K.; Thomas, David S. G.; Bailey, Richard M.; Holmes, Peter J.

2018-06-01

Sand ramps occur on a continuum of topographically-controlled landforms, ranging from purely aeolian features (climbing/falling dunes) to talus cones and alluvial fans. Sand ramps have been identified as potentially important palaeoenvironmental archives in dryland regions that possess relatively few Quaternary proxy records. Their utility however requires not only good age control of depositional phases but clear identification of process regimes, determined through morphological and sedimentological analyses, with several recent studies indicating the complexities of palaeoenvironmental interpretations and the controls of ramp development (Bateman et al., 2012; Rowell et al., 2018). Klipkraal Sands is a sand ramp on the north-eastern margin of the semi-arid Karoo that has been important for inferences of the extent of southern African Late Quaternary aeolian activity (Thomas et al., 2002). We reanalyse this feature, in the light of both its significance and other recent studies that have inferred extensive southern African LGM aeolian activity (Telfer et al., 2012, 2014). New sedimentological data and twelve OSL dates indicate the Klipkraal Sands formed episodically between 100-0.14 ka, rather than accumulating rapidly, while sedimentological data question the aeolian affinities of the bulk of the feature. Therefore, Klipkraal is reinterpreted as showing no particular affinity to the LGM, with sediments locally sourced with a significant colluvial component. Only the upper historical sediments can be clearly interpreted as aeolian deposits. A complex interplay of processes is suggested, for which a meaningful palaeoenvironmental interpretation cannot be easily defined. This implies that the local geomorphic processes and controls operating on sand ramps need to be established before they can be fully utilised as palaeoenvironmental archives, with implications for their interpretation worldwide.

Why Some Women Look Young for Their Age

PubMed Central

Gunn, David A.; Rexbye, Helle; Griffiths, Christopher E. M.; Murray, Peter G.; Fereday, Amelia; Catt, Sharon D.; Tomlin, Cyrena C.; Strongitharm, Barbara H.; Perrett, Dave I.; Catt, Michael; Mayes, Andrew E.; Messenger, Andrew G.; Green, Martin R.; van der Ouderaa, Frans; Vaupel, James W.; Christensen, Kaare

2009-01-01

The desire of many to look young for their age has led to the establishment of a large cosmetics industry. However, the features of appearance that primarily determine how old women look for their age and whether genetic or environmental factors predominately influence such features are largely unknown. We studied the facial appearance of 102 pairs of female Danish twins aged 59 to 81 as well as 162 British females aged 45 to 75. Skin wrinkling, hair graying and lip height were significantly and independently associated with how old the women looked for their age. The appearance of facial sun-damage was also found to be significantly correlated to how old women look for their age and was primarily due to its commonality with the appearance of skin wrinkles. There was also considerable variation in the perceived age data that was unaccounted for. Composite facial images created from women who looked young or old for their age indicated that the structure of subcutaneous tissue was partly responsible. Heritability analyses of the appearance features revealed that perceived age, pigmented age spots, skin wrinkles and the appearance of sun-damage were influenced more or less equally by genetic and environmental factors. Hair graying, recession of hair from the forehead and lip height were influenced mainly by genetic factors whereas environmental factors influenced hair thinning. These findings indicate that women who look young for their age have large lips, avoid sun-exposure and possess genetic factors that protect against the development of gray hair and skin wrinkles. The findings also demonstrate that perceived age is a better biomarker of skin, hair and facial aging than chronological age. PMID:19956599

Using listener-based perceptual features as intermediate representations in music information retrieval.

PubMed

Friberg, Anders; Schoonderwaldt, Erwin; Hedblad, Anton; Fabiani, Marco; Elowsson, Anders

2014-10-01

The notion of perceptual features is introduced for describing general music properties based on human perception. This is an attempt at rethinking the concept of features, aiming to approach the underlying human perception mechanisms. Instead of using concepts from music theory such as tones, pitches, and chords, a set of nine features describing overall properties of the music was selected. They were chosen from qualitative measures used in psychology studies and motivated from an ecological approach. The perceptual features were rated in two listening experiments using two different data sets. They were modeled both from symbolic and audio data using different sets of computational features. Ratings of emotional expression were predicted using the perceptual features. The results indicate that (1) at least some of the perceptual features are reliable estimates; (2) emotion ratings could be predicted by a small combination of perceptual features with an explained variance from 75% to 93% for the emotional dimensions activity and valence; (3) the perceptual features could only to a limited extent be modeled using existing audio features. Results clearly indicated that a small number of dedicated features were superior to a "brute force" model using a large number of general audio features.

A System-Level Pathway-Phenotype Association Analysis Using Synthetic Feature Random Forest

PubMed Central

Pan, Qinxin; Hu, Ting; Malley, James D.; Andrew, Angeline S.; Karagas, Margaret R.; Moore, Jason H.

2015-01-01

As the cost of genome-wide genotyping decreases, the number of genome-wide association studies (GWAS) has increased considerably. However, the transition from GWAS findings to the underlying biology of various phenotypes remains challenging. As a result, due to its system-level interpretability, pathway analysis has become a popular tool for gaining insights on the underlying biology from high-throughput genetic association data. In pathway analyses, gene sets representing particular biological processes are tested for significant associations with a given phenotype. Most existing pathway analysis approaches rely on single-marker statistics and assume that pathways are independent of each other. As biological systems are driven by complex biomolecular interactions, embracing the complex relationships between single-nucleotide polymorphisms (SNPs) and pathways needs to be addressed. To incorporate the complexity of gene-gene interactions and pathway-pathway relationships, we propose a system-level pathway analysis approach, synthetic feature random forest (SF-RF), which is designed to detect pathway-phenotype associations without making assumptions about the relationships among SNPs or pathways. In our approach, the genotypes of SNPs in a particular pathway are aggregated into a synthetic feature representing that pathway via Random Forest (RF). Multiple synthetic features are analyzed using RF simultaneously and the significance of a synthetic feature indicates the significance of the corresponding pathway. We further complement SF-RF with pathway-based Statistical Epistasis Network (SEN) analysis that evaluates interactions among pathways. By investigating the pathway SEN, we hope to gain additional insights into the genetic mechanisms contributing to the pathway-phenotype association. We apply SF-RF to a population-based genetic study of bladder cancer and further investigate the mechanisms that help explain the pathway-phenotype associations using SEN. The bladder cancer associated pathways we found are both consistent with existing biological knowledge and reveal novel and plausible hypotheses for future biological validations. PMID:24535726

Distribution features of biological hazardous pollutants in residential environments in Korea.

PubMed

Lee, Cheol Min; Hong, Soo Jong; Kim, Yoon Shin; Park, Gee Yong; Nam Goung, Sun Ju; Kim, Kyung Hwan

2014-01-01

This research has been conducted continuously since 2009 as part of a cohort of studies examining relationships between asthma and genetic factors, dietary habits, and environmental factors. Based on data from environmental research on house dust mites and endotoxins, which are widely known as pollutants in bedding that cause asthma in pregnant women and children, this work was conducted to obtain basic data that can be used in future cohort studies that analyze links between distribution of biological hazards and physical features of residential environments. The detection rates of house dust mite allergens, Der p1 and Der f1, were 52.7 and 86.5%, respectively, indicating that Der f1 is a dominant species in domestic indoor environments. According to comparisons between concentrations of house dust mites and endotoxins in bedding of pregnant women and children, Der p1 and endotoxins showed significantly lower concentrations in bedding of pregnant women compared with those in bedding of children, whereas Der f1 showed no significant difference in concentration according to bedding.

Clarifying Interpersonal Heterogeneity in Borderline Personality Disorder Using Latent Mixture Modeling

PubMed Central

Wright, Aidan G.C.; Hallquist, Michael N.; Morse, Jennifer Q.; Scott, Lori N.; Stepp, Stephanie D.; Nolf, Kimberly A.; Pilkonis, Paul A.

2013-01-01

Significant interpersonal impairment is a cardinal feature of borderline personality disorder (BPD). However, past research has demonstrated that the interpersonal profile associated with BPD varies across samples, evidence for considerable interpersonal heterogeneity. The current study used Inventory of Interpersonal Problems – Circumplex (IIP-C; Alden, Wiggins, & Pincus, 1990) scale scores to investigate interpersonal inhibitions and excesses in a large sample (N = 255) selected for significant borderline pathology. Results indicated that BPD symptom counts were unrelated to the primary dimensions of the IIP-C, but were related to generalized interpersonal distress. A latent class analysis clarified this finding by revealing six homogeneous interpersonal classes with prototypical profiles associated with Intrusive, Vindictive, Avoidant, Nonassertive, and moderate and severe Exploitable interpersonal problems. These classes differed in clinically relevant features (e.g., antisocial behaviors, self-injury, past suicide attempts). Findings are discussed in terms of the incremental clinical utility of the interpersonal circumplex model and the implications for developmental and nosological models of BPD. PMID:23514179

Regulation of osteogenesis by micro/nano hierarchical titanium surfaces through a Rock-Wnt5a feedback loop.

PubMed

Yu, Yonglin; Shen, Xinkun; Liu, Junjie; Hu, Yan; Ran, Qichun; Mu, Caiyun; Cai, Kaiyong

2018-05-28

Titanium substrates with micro/nano hierarchical features could positively mediate the osteogenesis of a titanium implant; nevertheless, the underlying molecular mechanism needs to be further revealed. In this work, we fabricated a micro/nano hierarchically structured Ti (MNT) sample and attempted to evaluate its topography-mediated biological effects and potential molecular mechanisms in vitro. The results proved that MNT could not only affect cell morphology and osteogenic differentiation, but also regulate ROCK activity cell biological functions of osteoblasts involved in ROCK activation, β-catenin accumulation, and high-Wnt5a expression in respect to topographical features. Moreover, blockade of ROCK activation resulted in significant inhibition of cell differentiation and Wnt5a expression. Furthermore, the anti-Wnt5a significantly down-regulated ROCK activity. In short, these results indicate the important role of ROCK-Wnt5a feedback loop in regulating cell differentiation by topographies. Copyright © 2018. Published by Elsevier B.V.

Single- and double-row repair for rotator cuff tears - biology and mechanics.

PubMed

Papalia, Rocco; Franceschi, Francesco; Vasta, Sebastiano; Zampogna, Biagio; Maffulli, Nicola; Denaro, Vincenzo

2012-01-01

We critically review the existing studies comparing the features of single- and double-row repair, and discuss suggestions about the surgical indications for the two repair techniques. All currently available studies comparing the biomechanical, clinical and the biological features of single and double row. Biomechanically, the double-row repair has greater performances in terms of higher initial fixation strength, greater footprint coverage, improved contact area and pressure, decreased gap formation, and higher load to failure. Results of clinical studies demonstrate no significantly better outcomes for double-row compared to single-row repair. Better results are achieved by double-row repair for larger lesions (tear size 2.5-3.5 cm). Considering the lack of statistically significant differences between the two techniques and that the double row is a high cost and a high surgical skill-dependent technique, we suggest using the double-row technique only in strictly selected patients. Copyright © 2012 S. Karger AG, Basel.

Detecting Eating Psychopathology in Female Athletes by Asking About Exercise: Use of the Compulsive Exercise Test.

PubMed

Plateau, Carolyn R; Arcelus, Jon; Meyer, Caroline

2017-11-01

The present study assessed the suitability of the Compulsive Exercise Test (athlete version; CET-A) for identifying female athletes with clinically significant features related to or comparable with eating psychopathology. Three hundred and sixty-one female athletes (including 12 with a clinically diagnosed eating disorder) completed the Eating Disorders Examination Questionnaire and the CET-A. Receiver operating curve analysis was employed to identify a cut-off value on the CET-A, which could indicate clinically significant features related to or comparable with eating psychopathology among female athletes. The analysis demonstrated that a CET-A score of 10 successfully discriminated female athletes with a current eating disorder. The results suggest that the CET-A may be a suitable tool for detecting eating psychopathology in female athletes. Additional longitudinal research is needed to evaluate the predictive value of the CET-A. Copyright © 2017 John Wiley & Sons, Ltd and Eating Disorders Association. Copyright © 2017 John Wiley & Sons, Ltd and Eating Disorders Association.

Clinical significance of rare copy number variations in epilepsy: a case-control survey using microarray-based comparative genomic hybridization.

PubMed

Striano, Pasquale; Coppola, Antonietta; Paravidino, Roberta; Malacarne, Michela; Gimelli, Stefania; Robbiano, Angela; Traverso, Monica; Pezzella, Marianna; Belcastro, Vincenzo; Bianchi, Amedeo; Elia, Maurizio; Falace, Antonio; Gazzerro, Elisabetta; Ferlazzo, Edoardo; Freri, Elena; Galasso, Roberta; Gobbi, Giuseppe; Molinatto, Cristina; Cavani, Simona; Zuffardi, Orsetta; Striano, Salvatore; Ferrero, Giovanni Battista; Silengo, Margherita; Cavaliere, Maria Luigia; Benelli, Matteo; Magi, Alberto; Piccione, Maria; Dagna Bricarelli, Franca; Coviello, Domenico A; Fichera, Marco; Minetti, Carlo; Zara, Federico

2012-03-01

To perform an extensive search for genomic rearrangements by microarray-based comparative genomic hybridization in patients with epilepsy. Prospective cohort study. Epilepsy centers in Italy. Two hundred seventy-nine patients with unexplained epilepsy, 265 individuals with nonsyndromic mental retardation but no epilepsy, and 246 healthy control subjects were screened by microarray-based comparative genomic hybridization. Identification of copy number variations (CNVs) and gene enrichment. Rare CNVs occurred in 26 patients (9.3%) and 16 healthy control subjects (6.5%) (P = .26). The CNVs identified in patients were larger (P = .03) and showed higher gene content (P = .02) than those in control subjects. The CNVs larger than 1 megabase (P = .002) and including more than 10 genes (P = .005) occurred more frequently in patients than in control subjects. Nine patients (34.6%) among those harboring rare CNVs showed rearrangements associated with emerging microdeletion or microduplication syndromes. Mental retardation and neuropsychiatric features were associated with rare CNVs (P = .004), whereas epilepsy type was not. The CNV rate in patients with epilepsy and mental retardation or neuropsychiatric features is not different from that observed in patients with mental retardation only. Moreover, significant enrichment of genes involved in ion transport was observed within CNVs identified in patients with epilepsy. Patients with epilepsy show a significantly increased burden of large, rare, gene-rich CNVs, particularly when associated with mental retardation and neuropsychiatric features. The limited overlap between CNVs observed in the epilepsy group and those observed in the group with mental retardation only as well as the involvement of specific (ion channel) genes indicate a specific association between the identified CNVs and epilepsy. Screening for CNVs should be performed for diagnostic purposes preferentially in patients with epilepsy and mental retardation or neuropsychiatric features.

Cascade detection for the extraction of localized sequence features; specificity results for HIV-1 protease and structure-function results for the Schellman loop.

PubMed

Newell, Nicholas E

2011-12-15

The extraction of the set of features most relevant to function from classified biological sequence sets is still a challenging problem. A central issue is the determination of expected counts for higher order features so that artifact features may be screened. Cascade detection (CD), a new algorithm for the extraction of localized features from sequence sets, is introduced. CD is a natural extension of the proportional modeling techniques used in contingency table analysis into the domain of feature detection. The algorithm is successfully tested on synthetic data and then applied to feature detection problems from two different domains to demonstrate its broad utility. An analysis of HIV-1 protease specificity reveals patterns of strong first-order features that group hydrophobic residues by side chain geometry and exhibit substantial symmetry about the cleavage site. Higher order results suggest that favorable cooperativity is weak by comparison and broadly distributed, but indicate possible synergies between negative charge and hydrophobicity in the substrate. Structure-function results for the Schellman loop, a helix-capping motif in proteins, contain strong first-order features and also show statistically significant cooperativities that provide new insights into the design of the motif. These include a new 'hydrophobic staple' and multiple amphipathic and electrostatic pair features. CD should prove useful not only for sequence analysis, but also for the detection of multifactor synergies in cross-classified data from clinical studies or other sources. Windows XP/7 application and data files available at: https://sites.google.com/site/cascadedetect/home. nacnewell@comcast.net Supplementary information is available at Bioinformatics online.

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

NASA Astrophysics Data System (ADS)

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.

Structure and Function in Homodimeric Enzymes: Simulations of Cooperative and Independent Functional Motions.

PubMed

Wells, Stephen A; van der Kamp, Marc W; McGeagh, John D; Mulholland, Adrian J

2015-01-01

Large-scale conformational change is a common feature in the catalytic cycles of enzymes. Many enzymes function as homodimers with active sites that contain elements from both chains. Symmetric and anti-symmetric cooperative motions in homodimers can potentially lead to correlated active site opening and/or closure, likely to be important for ligand binding and release. Here, we examine such motions in two different domain-swapped homodimeric enzymes: the DcpS scavenger decapping enzyme and citrate synthase. We use and compare two types of all-atom simulations: conventional molecular dynamics simulations to identify physically meaningful conformational ensembles, and rapid geometric simulations of flexible motion, biased along normal mode directions, to identify relevant motions encoded in the protein structure. The results indicate that the opening/closure motions are intrinsic features of both unliganded enzymes. In DcpS, conformational change is dominated by an anti-symmetric cooperative motion, causing one active site to close as the other opens; however a symmetric motion is also significant. In CS, we identify that both symmetric (suggested by crystallography) and asymmetric motions are features of the protein structure, and as a result the behaviour in solution is largely non-cooperative. The agreement between two modelling approaches using very different levels of theory indicates that the behaviours are indeed intrinsic to the protein structures. Geometric simulations correctly identify and explore large amplitudes of motion, while molecular dynamics simulations indicate the ranges of motion that are energetically feasible. Together, the simulation approaches are able to reveal unexpected functionally relevant motions, and highlight differences between enzymes.

Structure and Function in Homodimeric Enzymes: Simulations of Cooperative and Independent Functional Motions

PubMed Central

McGeagh, John D.; Mulholland, Adrian J.

2015-01-01

Large-scale conformational change is a common feature in the catalytic cycles of enzymes. Many enzymes function as homodimers with active sites that contain elements from both chains. Symmetric and anti-symmetric cooperative motions in homodimers can potentially lead to correlated active site opening and/or closure, likely to be important for ligand binding and release. Here, we examine such motions in two different domain-swapped homodimeric enzymes: the DcpS scavenger decapping enzyme and citrate synthase. We use and compare two types of all-atom simulations: conventional molecular dynamics simulations to identify physically meaningful conformational ensembles, and rapid geometric simulations of flexible motion, biased along normal mode directions, to identify relevant motions encoded in the protein structure. The results indicate that the opening/closure motions are intrinsic features of both unliganded enzymes. In DcpS, conformational change is dominated by an anti-symmetric cooperative motion, causing one active site to close as the other opens; however a symmetric motion is also significant. In CS, we identify that both symmetric (suggested by crystallography) and asymmetric motions are features of the protein structure, and as a result the behaviour in solution is largely non-cooperative. The agreement between two modelling approaches using very different levels of theory indicates that the behaviours are indeed intrinsic to the protein structures. Geometric simulations correctly identify and explore large amplitudes of motion, while molecular dynamics simulations indicate the ranges of motion that are energetically feasible. Together, the simulation approaches are able to reveal unexpected functionally relevant motions, and highlight differences between enzymes. PMID:26241964

Portable automatic text classification for adverse drug reaction detection via multi-corpus training.

PubMed

Sarker, Abeed; Gonzalez, Graciela

2015-02-01

Automatic detection of adverse drug reaction (ADR) mentions from text has recently received significant interest in pharmacovigilance research. Current research focuses on various sources of text-based information, including social media-where enormous amounts of user posted data is available, which have the potential for use in pharmacovigilance if collected and filtered accurately. The aims of this study are: (i) to explore natural language processing (NLP) approaches for generating useful features from text, and utilizing them in optimized machine learning algorithms for automatic classification of ADR assertive text segments; (ii) to present two data sets that we prepared for the task of ADR detection from user posted internet data; and (iii) to investigate if combining training data from distinct corpora can improve automatic classification accuracies. One of our three data sets contains annotated sentences from clinical reports, and the two other data sets, built in-house, consist of annotated posts from social media. Our text classification approach relies on generating a large set of features, representing semantic properties (e.g., sentiment, polarity, and topic), from short text nuggets. Importantly, using our expanded feature sets, we combine training data from different corpora in attempts to boost classification accuracies. Our feature-rich classification approach performs significantly better than previously published approaches with ADR class F-scores of 0.812 (previously reported best: 0.770), 0.538 and 0.678 for the three data sets. Combining training data from multiple compatible corpora further improves the ADR F-scores for the in-house data sets to 0.597 (improvement of 5.9 units) and 0.704 (improvement of 2.6 units) respectively. Our research results indicate that using advanced NLP techniques for generating information rich features from text can significantly improve classification accuracies over existing benchmarks. Our experiments illustrate the benefits of incorporating various semantic features such as topics, concepts, sentiments, and polarities. Finally, we show that integration of information from compatible corpora can significantly improve classification performance. This form of multi-corpus training may be particularly useful in cases where data sets are heavily imbalanced (e.g., social media data), and may reduce the time and costs associated with the annotation of data in the future. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.

Portable Automatic Text Classification for Adverse Drug Reaction Detection via Multi-corpus Training

PubMed Central

Gonzalez, Graciela

2014-01-01

Objective Automatic detection of Adverse Drug Reaction (ADR) mentions from text has recently received significant interest in pharmacovigilance research. Current research focuses on various sources of text-based information, including social media — where enormous amounts of user posted data is available, which have the potential for use in pharmacovigilance if collected and filtered accurately. The aims of this study are: (i) to explore natural language processing approaches for generating useful features from text, and utilizing them in optimized machine learning algorithms for automatic classification of ADR assertive text segments; (ii) to present two data sets that we prepared for the task of ADR detection from user posted internet data; and (iii) to investigate if combining training data from distinct corpora can improve automatic classification accuracies. Methods One of our three data sets contains annotated sentences from clinical reports, and the two other data sets, built in-house, consist of annotated posts from social media. Our text classification approach relies on generating a large set of features, representing semantic properties (e.g., sentiment, polarity, and topic), from short text nuggets. Importantly, using our expanded feature sets, we combine training data from different corpora in attempts to boost classification accuracies. Results Our feature-rich classification approach performs significantly better than previously published approaches with ADR class F-scores of 0.812 (previously reported best: 0.770), 0.538 and 0.678 for the three data sets. Combining training data from multiple compatible corpora further improves the ADR F-scores for the in-house data sets to 0.597 (improvement of 5.9 units) and 0.704 (improvement of 2.6 units) respectively. Conclusions Our research results indicate that using advanced NLP techniques for generating information rich features from text can significantly improve classification accuracies over existing benchmarks. Our experiments illustrate the benefits of incorporating various semantic features such as topics, concepts, sentiments, and polarities. Finally, we show that integration of information from compatible corpora can significantly improve classification performance. This form of multi-corpus training may be particularly useful in cases where data sets are heavily imbalanced (e.g., social media data), and may reduce the time and costs associated with the annotation of data in the future. PMID:25451103

Electron Microscopy and Analytical X-ray Characterization of Compositional and Nanoscale Structural Changes in Fossil Bone

NASA Astrophysics Data System (ADS)

Boatman, Elizabeth Marie

The nanoscale structure of compact bone contains several features that are direct indicators of bulk tissue mechanical properties. Fossil bone tissues represent unique opportunities to understand the compact bone structure/property relationships from a deep time perspective, offering a possible array of new insights into bone diseases, biomimicry of composite materials, and basic knowledge of bioapatite composition and nanoscale bone structure. To date, most work with fossil bone has employed microscale techniques and has counter-indicated the survival of bioapatite and other nanoscale structural features. The obvious disconnect between the use of microscale techniques and the discernment of nanoscale structure has prompted this work. The goal of this study was to characterize the nanoscale constituents of fossil compact bone by applying a suite of diffraction, microscopy, and spectrometry techniques, representing the highest levels of spatial and energy resolution available today, and capable of complementary structural and compositional characterization from the micro- to the nanoscale. Fossil dinosaur and crocodile long bone specimens, as well as modern ratite and crocodile femurs, were acquired from the UC Museum of Paleontology. Preserved physiological features of significance were documented with scanning electron microscopy back-scattered imaging. Electron microprobe wavelength-dispersive X-ray spectroscopy (WDS) revealed fossil bone compositions enriched in fluorine with a complementary loss of oxygen. X-ray diffraction analyses demonstrated that all specimens were composed of apatite. Transmission electron microscopy (TEM) imaging revealed preserved nanocrystallinity in the fossil bones and electron diffraction studies further identified these nanocrystallites as apatite. Tomographic analyses of nanoscale elements imaged by TEM and small angle X-ray scattering were performed, with the results of each analysis further indicating that nanoscale structure is highly conserved in these four fossil specimens. Finally, the results of this study indicate that bioapatite can be preserved in even the most ancient vertebrate specimens, further supporting the idea that fossilization is a preservational process. This work also underlines the importance of using appropriately selected characterization and analytical techniques for the study of fossil bone, especially from the perspective of spatial resolution and the scale of the bone structural features in question.

Identification of features in indexed data and equipment therefore

DOEpatents

Jarman, Kristin H [Richland, WA; Daly, Don Simone [Richland, WA; Anderson, Kevin K [Richland, WA; Wahl, Karen L [Richland, WA

2002-04-02

Embodiments of the present invention provide methods of identifying a feature in an indexed dataset. Such embodiments encompass selecting an initial subset of indices, the initial subset of indices being encompassed by an initial window-of-interest and comprising at least one beginning index and at least one ending index; computing an intensity weighted measure of dispersion for the subset of indices using a subset of responses corresponding to the subset of indices; and comparing the intensity weighted measure of dispersion to a dispersion critical value determined from an expected value of the intensity weighted measure of dispersion under a null hypothesis of no transient feature present. Embodiments of the present invention also encompass equipment configured to perform the methods of the present invention.

Kinematic Measurements of the Vocal-Fold Displacement Waveform in Typical Children and Adult Populations: Quantification of High-Speed Endoscopic Videos

PubMed Central

Donohue, Kevin D.; Unnikrishnan, Harikrishnan; Kryscio, Richard J.

2015-01-01

Purpose This article presents a quantitative method for assessing instantaneous and average lateral vocal-fold motion from high-speed digital imaging, with a focus on developmental changes in vocal-fold kinematics during childhood. Method Vocal-fold vibrations were analyzed for 28 children (aged 5–11 years) and 28 adults (aged 21–45 years) without voice disorders. The following kinematic features were analyzed from the vocal-fold displacement waveforms: relative velocity-based features (normalized average and peak opening and closing velocities), relative acceleration-based features (normalized peak opening and closing accelerations), speed quotient, and normalized peak displacement. Results Children exhibited significantly larger normalized peak displacements, normalized average and peak opening velocities, normalized average and peak closing velocities, peak opening and closing accelerations, and speed quotient compared to adult women. Values of normalized average closing velocity and speed quotient were higher in children compared to adult men. Conclusions When compared to adult men, developing children typically have higher estimates of kinematic features related to normalized displacement and its derivatives. In most cases, the kinematic features of children are closer to those of adult men than adult women. Even though boys experience greater changes in glottal length and pitch as they mature, results indicate that girls experience greater changes in kinematic features compared to boys. PMID:25652615

Features of the Correlation Structure of Price Indices

PubMed Central

Gao, Xiangyun; An, Haizhong; Zhong, Weiqiong

2013-01-01

What are the features of the correlation structure of price indices? To answer this question, 5 types of price indices, including 195 specific price indices from 2003 to 2011, were selected as sample data. To build a weighted network of price indices each price index is represented by a vertex, and a positive correlation between two price indices is represented by an edge. We studied the features of the weighted network structure by applying economic theory to the analysis of complex network parameters. We found that the frequency of the price indices follows a normal distribution by counting the weighted degrees of the nodes, and we identified the price indices which have an important impact on the network's structure. We found out small groups in the weighted network by the methods of k-core and k-plex. We discovered structure holes in the network by calculating the hierarchy of the nodes. Finally, we found that the price indices weighted network has a small-world effect by calculating the shortest path. These results provide a scientific basis for macroeconomic control policies. PMID:23593399

Identifying key radiogenomic associations between DCE-MRI and micro-RNA expressions for breast cancer

NASA Astrophysics Data System (ADS)

Samala, Ravi K.; Chan, Heang-Ping; Hadjiiski, Lubomir; Helvie, Mark A.; Kim, Renaid

2017-03-01

Understanding the key radiogenomic associations for breast cancer between DCE-MRI and micro-RNA expressions is the foundation for the discovery of radiomic features as biomarkers for assessing tumor progression and prognosis. We conducted a study to analyze the radiogenomic associations for breast cancer using the TCGA-TCIA data set. The core idea that tumor etiology is a function of the behavior of miRNAs is used to build the regression models. The associations based on regression are analyzed for three study outcomes: diagnosis, prognosis, and treatment. The diagnosis group consists of miRNAs associated with clinicopathologic features of breast cancer and significant aberration of expression in breast cancer patients. The prognosis group consists of miRNAs which are closely associated with tumor suppression and regulation of cell proliferation and differentiation. The treatment group consists of miRNAs that contribute significantly to the regulation of metastasis thereby having the potential to be part of therapeutic mechanisms. As a first step, important miRNA expressions were identified and their ability to classify the clinical phenotypes based on the study outcomes was evaluated using the area under the ROC curve (AUC) as a figure-of-merit. The key mapping between the selected miRNAs and radiomic features were determined using least absolute shrinkage and selection operator (LASSO) regression analysis within a two-loop leave-one-out cross-validation strategy. These key associations indicated a number of radiomic features from DCE-MRI to be potential biomarkers for the three study outcomes.

Contingent capture can occur at specific feature values: behavioral and electrophysiological evidence.

PubMed

Jiao, Jun; Zhao, Guang; Wang, Qi; Zhang, Kan; Li, Hong; Sun, Hong-Jin; Liu, Qiang

2013-02-01

The notion that attentional top-down control can be tuned to a stimulus feature is widely accepted. Although previous studies suggested that the stimulus-driven attentional capture could be contingent on top-down attentional control settings, it was uncertain whether contingent capture can occur at a specific feature value. Three experiments were conducted to address this issue using both behavioral and ERPs measures. Participants were required to respond to one color singleton in the search display (target) but refrain from responding to the search display containing another color singleton (nontarget). When target and nontarget belonged to different color categories (Experiment 1), only the target-color cue and within category irrelevant-color cue elicited the significant cue validity effect (i.e. RTs were shorter when the target was presented at the same location as the preceding cue rather than at a different location); they also lead to a robust N2pc effect, indicative of attention-capture. In addition, these two cue types had similar attention-capturing capacity. However, when target and nontarget belonged to the same color category (Experiments 2 and 3), only the target-color cue elicited the significant cue validity effect and the robust N2pc effect. The same within category irrelevant-color cue no longer elicited the cue validity effect, and the N2pc effect was also attenuated. Present findings suggest that contingent capture can occur at a specific feature value. Copyright © 2012 Elsevier B.V. All rights reserved.

Clinical application of modified bag-of-features coupled with hybrid neural-based classifier in dengue fever classification using gene expression data.

PubMed

Chatterjee, Sankhadeep; Dey, Nilanjan; Shi, Fuqian; Ashour, Amira S; Fong, Simon James; Sen, Soumya

2018-04-01

Dengue fever detection and classification have a vital role due to the recent outbreaks of different kinds of dengue fever. Recently, the advancement in the microarray technology can be employed for such classification process. Several studies have established that the gene selection phase takes a significant role in the classifier performance. Subsequently, the current study focused on detecting two different variations, namely, dengue fever (DF) and dengue hemorrhagic fever (DHF). A modified bag-of-features method has been proposed to select the most promising genes in the classification process. Afterward, a modified cuckoo search optimization algorithm has been engaged to support the artificial neural (ANN-MCS) to classify the unknown subjects into three different classes namely, DF, DHF, and another class containing convalescent and normal cases. The proposed method has been compared with other three well-known classifiers, namely, multilayer perceptron feed-forward network (MLP-FFN), artificial neural network (ANN) trained with cuckoo search (ANN-CS), and ANN trained with PSO (ANN-PSO). Experiments have been carried out with different number of clusters for the initial bag-of-features-based feature selection phase. After obtaining the reduced dataset, the hybrid ANN-MCS model has been employed for the classification process. The results have been compared in terms of the confusion matrix-based performance measuring metrics. The experimental results indicated a highly statistically significant improvement with the proposed classifier over the traditional ANN-CS model.

Dyadic differences in friendships of adolescents with chronic pain compared with pain-free peers.

PubMed

Forgeron, Paula A; Chambers, Christine T; Cohen, Janice; Dick, Bruce D; Finley, G Allen; Lamontagne, Christine

2018-06-01

A multisite cross-sectional study was conducted to examine dyadic friendship features between adolescents with chronic pain (ACP) and their friends compared with non-pain adolescent friendship dyads and the association of these friendship features with loneliness and depressive symptoms. Participants completed a battery of standardized measures to capture friendship features (friendship quality, closeness, and perceived social support from friends) and indices of social-emotional well-being. Sixty-one same sex friendship dyads (122 adolescents) participated; 30 friendship dyads included an adolescent with chronic pain and 52 dyads were female. Adolescents with chronic pain scored significantly higher on measures of loneliness and depressive symptoms compared with all other participants. Hierarchical Multiple Regression analysis revealed that friendship features predicted loneliness and depressive symptoms. Chronic pain predicted loneliness and depressive symptoms above and beyond friendship features. Actor Partner Interdependence Modeling found perceived social support from friends had differing associations on loneliness and depressive symptoms for dyads with a chronic pain member compared with pain-free control dyads. Friendship features were associated with loneliness and depressive symptoms for adolescents, but friendship features alone did not explain loneliness and depressive symptoms for ACP. Further research is needed to understand whether pain-related social support improves loneliness and depressive symptoms for ACP. Furthermore, a more nuanced understanding of loneliness in this population is warranted. Strategies to help ACP garner needed social support from friends are needed to decrease rates of loneliness to improve long-term outcomes.

A Radio-genomics Approach for Identifying High Risk Estrogen Receptor-positive Breast Cancers on DCE-MRI: Preliminary Results in Predicting OncotypeDX Risk Scores

PubMed Central

Wan, Tao; Bloch, B. Nicolas; Plecha, Donna; Thompson, CheryI L.; Gilmore, Hannah; Jaffe, Carl; Harris, Lyndsay; Madabhushi, Anant

2016-01-01

To identify computer extracted imaging features for estrogen receptor (ER)-positive breast cancers on dynamic contrast en-hanced (DCE)-MRI that are correlated with the low and high OncotypeDX risk categories. We collected 96 ER-positivebreast lesions with low (<18, N = 55) and high (>30, N = 41) OncotypeDX recurrence scores. Each lesion was quantitatively charac-terize via 6 shape features, 3 pharmacokinetics, 4 enhancement kinetics, 4 intensity kinetics, 148 textural kinetics, 5 dynamic histogram of oriented gradient (DHoG), and 6 dynamic local binary pattern (DLBP) features. The extracted features were evaluated by a linear discriminant analysis (LDA) classifier in terms of their ability to distinguish low and high OncotypeDX risk categories. Classification performance was evaluated by area under the receiver operator characteristic curve (Az). The DHoG and DLBP achieved Az values of 0.84 and 0.80, respectively. The 6 top features identified via feature selection were subsequently combined with the LDA classifier to yield an Az of 0.87. The correlation analysis showed that DHoG (ρ = 0.85, P < 0.001) and DLBP (ρ = 0.83, P < 0.01) were significantly associated with the low and high risk classifications from the OncotypeDX assay. Our results indicated that computer extracted texture features of DCE-MRI were highly correlated with the high and low OncotypeDX risk categories for ER-positive cancers. PMID:26887643

Hitomi X-ray observation of the pulsar wind nebula G21.5-0.9

NASA Astrophysics Data System (ADS)

Aharonian, Felix; Akamatsu, Hiroki; Akimoto, Fumie; Allen, Steven W.; Angelini, Lorella; Audard, Marc; Awaki, Hisamitsu; Axelsson, Magnus; Bamba, Aya; Bautz, Marshall W.; Blandford, Roger; Brenneman, Laura W.; Brown, Gregory V.; Bulbul, Esra; Cackett, Edward M.; Chernyakova, Maria; Chiao, Meng P.; Coppi, Paolo S.; Costantini, Elisa; de Plaa, Jelle; de Vries, Cor P.; den Herder, Jan-Willem; Done, Chris; Dotani, Tadayasu; Ebisawa, Ken; Eckart, Megan E.; Enoto, Teruaki; Ezoe, Yuichiro; Fabian, Andrew C.; Ferrigno, Carlo; Foster, Adam R.; Fujimoto, Ryuichi; Fukazawa, Yasushi; Furuzawa, Akihiro; Galeazzi, Massimiliano; Gallo, Luigi C.; Gandhi, Poshak; Giustini, Margherita; Goldwurm, Andrea; Gu, Liyi; Guainazzi, Matteo; Haba, Yoshito; Hagino, Kouichi; Hamaguchi, Kenji; Harrus, Ilana M.; Hatsukade, Isamu; Hayashi, Katsuhiro; Hayashi, Takayuki; Hayashida, Kiyoshi; Hiraga, Junko S.; Hornschemeier, Ann; Hoshino, Akio; Hughes, John P.; Ichinohe, Yuto; Iizuka, Ryo; Inoue, Hajime; Inoue, Yoshiyuki; Ishida, Manabu; Ishikawa, Kumi; Ishisaki, Yoshitaka; Iwai, Masachika; Kaastra, Jelle; Kallman, Tim; Kamae, Tsuneyoshi; Kataoka, Jun; Katsuda, Satoru; Kawai, Nobuyuki; Kelley, Richard L.; Kilbourne, Caroline A.; Kitaguchi, Takao; Kitamoto, Shunji; Kitayama, Tetsu; Kohmura, Takayoshi; Kokubun, Motohide; Koyama, Katsuji; Koyama, Shu; Kretschmar, Peter; Krimm, Hans A.; Kubota, Aya; Kunieda, Hideyo; Laurent, Philippe; Lee, Shiu-Hang; Leutenegger, Maurice A.; Limousin, Olivier; Loewenstein, Michael; Long, Knox S.; Lumb, David; Madejski, Greg; Maeda, Yoshitomo; Maier, Daniel; Makishima, Kazuo; Markevitch, Maxim; Matsumoto, Hironori; Matsushita, Kyoko; McCammon, Dan; McNamara, Brian R.; Mehdipour, Missagh; Miller, Eric D.; Miller, Jon M.; Mineshige, Shin; Mitsuda, Kazuhisa; Mitsuishi, Ikuyuki; Miyazawa, Takuya; Mizuno, Tsunefumi; Mori, Hideyuki; Mori, Koji; Mukai, Koji; Murakami, Hiroshi; Mushotzky, Richard F.; Nakagawa, Takao; Nakajima, Hiroshi; Nakamori, Takeshi; Nakashima, Shinya; Nakazawa, Kazuhiro; Nobukawa, Kumiko K.; Nobukawa, Masayoshi; Noda, Hirofumi; Odaka, Hirokazu; Ohashi, Takaya; Ohno, Masanori; Okajima, Takashi; Ota, Naomi; Ozaki, Masanobu; Paerels, Frits; Paltani, Stéphane; Petre, Robert; Pinto, Ciro; Porter, Frederick S.; Pottschmidt, Katja; Reynolds, Christopher S.; Safi-Harb, Samar; Saito, Shinya; Sakai, Kazuhiro; Sasaki, Toru; Sato, Goro; Sato, Kosuke; Sato, Rie; Sawada, Makoto; Schartel, Norbert; Serlemtsos, Peter J.; Seta, Hiromi; Shidatsu, Megumi; Simionescu, Aurora; Smith, Randall K.; Soong, Yang; Stawarz, Łukasz; Sugawara, Yasuharu; Sugita, Satoshi; Szymkowiak, Andrew; Tajima, Hiroyasu; Takahashi, Hiromitsu; Takahashi, Tadayuki; Takeda, Shin'ichiro; Takei, Yoh; Tamagawa, Toru; Tamura, Takayuki; Tanaka, Takaaki; Tanaka, Yasuo; Tanaka, Yasuyuki T.; Tashiro, Makoto S.; Tawara, Yuzuru; Terada, Yukikatsu; Terashima, Yuichi; Tombesi, Francesco; Tomida, Hiroshi; Tsuboi, Yohko; Tsujimoto, Masahiro; Tsunemi, Hiroshi; Tsuru, Takeshi Go; Uchida, Hiroyuki; Uchiyama, Hideki; Uchiyama, Yasunobu; Ueda, Shutaro; Ueda, Yoshihiro; Uno, Shin'ichiro; Urry, C. Megan; Ursino, Eugenio; Watanabe, Shin; Werner, Norbert; Wilkins, Dan R.; Williams, Brian J.; Yamada, Shinya; Yamaguchi, Hiroya; Yamaoka, Kazutaka; Yamasaki, Noriko Y.; Yamauchi, Makoto; Yamauchi, Shigeo; Yaqoob, Tahir; Yatsu, Yoichi; Yonetoku, Daisuke; Zhuravleva, Irina; Zoghbi, Abderahmen; Sato, Toshiki; Nakaniwa, Nozomu; Murakami, Hiroaki; Guest, Benson

2018-04-01

We present results from the Hitomi X-ray observation of a young composite-type supernova remnant (SNR) G21.5-0.9, whose emission is dominated by the pulsar wind nebula (PWN) contribution. The X-ray spectra in the 0.8-80 keV range obtained with the Soft X-ray Spectrometer (SXS), Soft X-ray Imager, and Hard X-ray Imager (HXI) show a significant break in the continuum as previously found with the NuSTAR observation. After taking into account all known emissions from the SNR other than the PWN itself, we find that the Hitomi spectra can be fitted with a broken power law with photon indices of Γ1 = 1.74 ± 0.02 and Γ2 = 2.14 ± 0.01 below and above the break at 7.1 ± 0.3 keV, which is significantly lower than the NuSTAR result (˜9.0 keV). The spectral break cannot be reproduced by time-dependent particle injection one-zone spectral energy distribution models, which strongly indicates that a more complex emission model is needed, as suggested by recent theoretical models. We also search for narrow emission or absorption lines with the SXS, and perform a timing analysis of PSR J1833-1034 with the HXI and the Soft Gamma-ray Detector. No significant pulsation is found from the pulsar. However, unexpectedly, narrow absorption line features are detected in the SXS data at 4.2345 keV and 9.296 keV with a significance of 3.65 σ. While the origin of these features is not understood, their mere detection opens up a new field of research and was only possible with the high resolution, sensitivity, and ability to measure extended sources provided by an X-ray microcalorimeter.

Important LiDAR metrics for discriminating forest tree species in Central Europe

NASA Astrophysics Data System (ADS)

Shi, Yifang; Wang, Tiejun; Skidmore, Andrew K.; Heurich, Marco

2018-03-01

Numerous airborne LiDAR-derived metrics have been proposed for classifying tree species. Yet an in-depth ecological and biological understanding of the significance of these metrics for tree species mapping remains largely unexplored. In this paper, we evaluated the performance of 37 frequently used LiDAR metrics derived under leaf-on and leaf-off conditions, respectively, for discriminating six different tree species in a natural forest in Germany. We firstly assessed the correlation between these metrics. Then we applied a Random Forest algorithm to classify the tree species and evaluated the importance of the LiDAR metrics. Finally, we identified the most important LiDAR metrics and tested their robustness and transferability. Our results indicated that about 60% of LiDAR metrics were highly correlated to each other (|r| > 0.7). There was no statistically significant difference in tree species mapping accuracy between the use of leaf-on and leaf-off LiDAR metrics. However, combining leaf-on and leaf-off LiDAR metrics significantly increased the overall accuracy from 58.2% (leaf-on) and 62.0% (leaf-off) to 66.5% as well as the kappa coefficient from 0.47 (leaf-on) and 0.51 (leaf-off) to 0.58. Radiometric features, especially intensity related metrics, provided more consistent and significant contributions than geometric features for tree species discrimination. Specifically, the mean intensity of first-or-single returns as well as the mean value of echo width were identified as the most robust LiDAR metrics for tree species discrimination. These results indicate that metrics derived from airborne LiDAR data, especially radiometric metrics, can aid in discriminating tree species in a mixed temperate forest, and represent candidate metrics for tree species classification and monitoring in Central Europe.

Hitomi X-ray observation of the pulsar wind nebula G21.5-0.9

NASA Astrophysics Data System (ADS)

Hitomi Collaboration; Aharonian, Felix; Akamatsu, Hiroki; Akimoto, Fumie; Allen, Steven W.; Angelini, Lorella; Audard, Marc; Awaki, Hisamitsu; Axelsson, Magnus; Bamba, Aya; Bautz, Marshall W.; Blandford, Roger; Brenneman, Laura W.; Brown, Gregory V.; Bulbul, Esra; Cackett, Edward M.; Chernyakova, Maria; Chiao, Meng P.; Coppi, Paolo S.; Costantini, Elisa; de Plaa, Jelle; de Vries, Cor P.; den Herder, Jan-Willem; Done, Chris; Dotani, Tadayasu; Ebisawa, Ken; Eckart, Megan E.; Enoto, Teruaki; Ezoe, Yuichiro; Fabian, Andrew C.; Ferrigno, Carlo; Foster, Adam R.; Fujimoto, Ryuichi; Fukazawa, Yasushi; Furuzawa, Akihiro; Galeazzi, Massimiliano; Gallo, Luigi C.; Gandhi, Poshak; Giustini, Margherita; Goldwurm, Andrea; Gu, Liyi; Guainazzi, Matteo; Haba, Yoshito; Hagino, Kouichi; Hamaguchi, Kenji; Harrus, Ilana M.; Hatsukade, Isamu; Hayashi, Katsuhiro; Hayashi, Takayuki; Hayashida, Kiyoshi; Hiraga, Junko S.; Hornschemeier, Ann; Hoshino, Akio; Hughes, John P.; Ichinohe, Yuto; Iizuka, Ryo; Inoue, Hajime; Inoue, Yoshiyuki; Ishida, Manabu; Ishikawa, Kumi; Ishisaki, Yoshitaka; Iwai, Masachika; Kaastra, Jelle; Kallman, Tim; Kamae, Tsuneyoshi; Kataoka, Jun; Katsuda, Satoru; Kawai, Nobuyuki; Kelley, Richard L.; Kilbourne, Caroline A.; Kitaguchi, Takao; Kitamoto, Shunji; Kitayama, Tetsu; Kohmura, Takayoshi; Kokubun, Motohide; Koyama, Katsuji; Koyama, Shu; Kretschmar, Peter; Krimm, Hans A.; Kubota, Aya; Kunieda, Hideyo; Laurent, Philippe; Lee, Shiu-Hang; Leutenegger, Maurice A.; Limousin, Olivier; Loewenstein, Michael; Long, Knox S.; Lumb, David; Madejski, Greg; Maeda, Yoshitomo; Maier, Daniel; Makishima, Kazuo; Markevitch, Maxim; Matsumoto, Hironori; Matsushita, Kyoko; McCammon, Dan; McNamara, Brian R.; Mehdipour, Missagh; Miller, Eric D.; Miller, Jon M.; Mineshige, Shin; Mitsuda, Kazuhisa; Mitsuishi, Ikuyuki; Miyazawa, Takuya; Mizuno, Tsunefumi; Mori, Hideyuki; Mori, Koji; Mukai, Koji; Murakami, Hiroshi; Mushotzky, Richard F.; Nakagawa, Takao; Nakajima, Hiroshi; Nakamori, Takeshi; Nakashima, Shinya; Nakazawa, Kazuhiro; Nobukawa, Kumiko K.; Nobukawa, Masayoshi; Noda, Hirofumi; Odaka, Hirokazu; Ohashi, Takaya; Ohno, Masanori; Okajima, Takashi; Ota, Naomi; Ozaki, Masanobu; Paerels, Frits; Paltani, Stéphane; Petre, Robert; Pinto, Ciro; Porter, Frederick S.; Pottschmidt, Katja; Reynolds, Christopher S.; Safi-Harb, Samar; Saito, Shinya; Sakai, Kazuhiro; Sasaki, Toru; Sato, Goro; Sato, Kosuke; Sato, Rie; Sawada, Makoto; Schartel, Norbert; Serlemtsos, Peter J.; Seta, Hiromi; Shidatsu, Megumi; Simionescu, Aurora; Smith, Randall K.; Soong, Yang; Stawarz, Łukasz; Sugawara, Yasuharu; Sugita, Satoshi; Szymkowiak, Andrew; Tajima, Hiroyasu; Takahashi, Hiromitsu; Takahashi, Tadayuki; Takeda, Shin'ichiro; Takei, Yoh; Tamagawa, Toru; Tamura, Takayuki; Tanaka, Takaaki; Tanaka, Yasuo; Tanaka, Yasuyuki T.; Tashiro, Makoto S.; Tawara, Yuzuru; Terada, Yukikatsu; Terashima, Yuichi; Tombesi, Francesco; Tomida, Hiroshi; Tsuboi, Yohko; Tsujimoto, Masahiro; Tsunemi, Hiroshi; Tsuru, Takeshi Go; Uchida, Hiroyuki; Uchiyama, Hideki; Uchiyama, Yasunobu; Ueda, Shutaro; Ueda, Yoshihiro; Uno, Shin'ichiro; Urry, C. Megan; Ursino, Eugenio; Watanabe, Shin; Werner, Norbert; Wilkins, Dan R.; Williams, Brian J.; Yamada, Shinya; Yamaguchi, Hiroya; Yamaoka, Kazutaka; Yamasaki, Noriko Y.; Yamauchi, Makoto; Yamauchi, Shigeo; Yaqoob, Tahir; Yatsu, Yoichi; Yonetoku, Daisuke; Zhuravleva, Irina; Zoghbi, Abderahmen; Sato, Toshiki; Nakaniwa, Nozomu; Murakami, Hiroaki; Guest, Benson

2018-06-01

We present results from the Hitomi X-ray observation of a young composite-type supernova remnant (SNR) G21.5-0.9, whose emission is dominated by the pulsar wind nebula (PWN) contribution. The X-ray spectra in the 0.8-80 keV range obtained with the Soft X-ray Spectrometer (SXS), Soft X-ray Imager, and Hard X-ray Imager (HXI) show a significant break in the continuum as previously found with the NuSTAR observation. After taking into account all known emissions from the SNR other than the PWN itself, we find that the Hitomi spectra can be fitted with a broken power law with photon indices of Γ1 = 1.74 ± 0.02 and Γ2 = 2.14 ± 0.01 below and above the break at 7.1 ± 0.3 keV, which is significantly lower than the NuSTAR result (˜9.0 keV). The spectral break cannot be reproduced by time-dependent particle injection one-zone spectral energy distribution models, which strongly indicates that a more complex emission model is needed, as suggested by recent theoretical models. We also search for narrow emission or absorption lines with the SXS, and perform a timing analysis of PSR J1833-1034 with the HXI and the Soft Gamma-ray Detector. No significant pulsation is found from the pulsar. However, unexpectedly, narrow absorption line features are detected in the SXS data at 4.2345 keV and 9.296 keV with a significance of 3.65 σ. While the origin of these features is not understood, their mere detection opens up a new field of research and was only possible with the high resolution, sensitivity, and ability to measure extended sources provided by an X-ray microcalorimeter.

High-Temperature Magnetism as a Probe for Structural and Compositional Uniformity in Ligand-Capped Magnetite Nanoparticles

PubMed Central

2015-01-01

To investigate magnetostructural relationships in colloidal magnetite (Fe3O4) nanoparticles (NPs) at high temperature (300–900 K), we measured the temperature dependence of magnetization (M) of oleate-capped magnetite NPs ca. 20 nm in size. Magnetometry revealed an unusual irreversible high-temperature dependence of M for these NPs, with dip and loop features observed during heating–cooling cycles. Detailed characterizations of as-synthesized and annealed Fe3O4 NPs as well as reference ligand-free Fe3O4 NPs indicate that both types of features in M(T) are related to thermal decomposition of the capping ligands. The ligand decomposition upon the initial heating induces a reduction of Fe3+ to Fe2+ and the associated dip in M, leading to more structurally and compositionally uniform magnetite NPs. Having lost the protective ligands, the NPs continually sinter during subsequent heating cycles, resulting in divergent M curves featuring loops. The increase in M with sintering proceeds not only through elimination of a magnetically dead layer on the particle surface, as a result of a decrease in specific surface area with increasing size, but also through an uncommonly invoked effect resulting from a significant change in Fe3+/Fe2+ ratio with heat treatment. The interpretation of irreversible features in M(T) indicates that reversible M(T) behavior, conversely, can be expected only for ligand-free, structurally and compositionally uniform magnetite NPs, suggesting a general applicability of high-temperature M(T) measurements as an analytical method for probing the structure and composition of magnetic nanomaterials. PMID:25506407

Factors Affecting Journal Quality Indicator in Scopus (SCImago Journal Rank) in Obstetrics and Gynecology Journals: a Longitudinal Study (1999-2013).

PubMed

Jamali, Jamshid; Salehi-Marzijarani, Mohammad; Ayatollahi, Seyyed Mohammad Taghi

2014-12-01

Awareness of the latest scientific research and publishing articles in top journals is one of the major concerns of health researchers. In this study, we first introduced top journals of obstetrics and gynecology field based on their Impact Factor (IF), Eigenfactor Score (ES) and SCImago Journal Rank (SJR) indicator indexed in Scopus databases and then the scientometric features of longitudinal changes of SJR in this field were presented. In our analytical and bibiliometric study, we included all the journals of obstetrics and gynecology field which were indexed by Scopus from 1999 to 2013. The scientometric features in Scopus were derived from SCImago Institute and IF and ES were obtained from Journal Citation Report through the Institute for Scientific Information. Generalized Estimating Equation was used to assess the scientometric features affecting SJR. From 256 journals reviewed, 54.2% and 41.8% were indexed in the Pubmed and the Web of Sciences, respectively. Human Reproduction Update based on the IF (5.924±2.542) and SJR (2.682±1.185), and American Journal of obstetrics and gynecology based on the ES (0.05685±0.00633) obtained the first rank among the other journals. Time, Index in Pubmed, H_index, Citable per Document, Cites per Document, and IF affected changes of SJR in the period of study. Our study showed a significant association between SJR and scientometric features in obstetrics and gynecology journals. According to this relationship, SJR may be an appropriate index for assessing journal quality.

Factors Affecting Journal Quality Indicator in Scopus (SCImago Journal Rank) in Obstetrics and Gynecology Journals: a Longitudinal Study (1999-2013)

PubMed Central

Jamali, Jamshid; Salehi-Marzijarani, Mohammad; Ayatollahi, Seyyed Mohammad Taghi

2014-01-01

Introduction: Awareness of the latest scientific research and publishing articles in top journals is one of the major concerns of health researchers. In this study, we first introduced top journals of obstetrics and gynecology field based on their Impact Factor (IF), Eigenfactor Score (ES) and SCImago Journal Rank (SJR) indicator indexed in Scopus databases and then the scientometric features of longitudinal changes of SJR in this field were presented. Method and material: In our analytical and bibiliometric study, we included all the journals of obstetrics and gynecology field which were indexed by Scopus from 1999 to 2013. The scientometric features in Scopus were derived from SCImago Institute and IF and ES were obtained from Journal Citation Report through the Institute for Scientific Information. Generalized Estimating Equation was used to assess the scientometric features affecting SJR. Result: From 256 journals reviewed, 54.2% and 41.8% were indexed in the Pubmed and the Web of Sciences, respectively. Human Reproduction Update based on the IF (5.924±2.542) and SJR (2.682±1.185), and American Journal of obstetrics and gynecology based on the ES (0.05685±0.00633) obtained the first rank among the other journals. Time, Index in Pubmed, H_index, Citable per Document, Cites per Document, and IF affected changes of SJR in the period of study. Discussion: Our study showed a significant association between SJR and scientometric features in obstetrics and gynecology journals. According to this relationship, SJR may be an appropriate index for assessing journal quality. PMID:25684846

Stress assessment based on EEG univariate features and functional connectivity measures.

PubMed

Alonso, J F; Romero, S; Ballester, M R; Antonijoan, R M; Mañanas, M A

2015-07-01

The biological response to stress originates in the brain but involves different biochemical and physiological effects. Many common clinical methods to assess stress are based on the presence of specific hormones and on features extracted from different signals, including electrocardiogram, blood pressure, skin temperature, or galvanic skin response. The aim of this paper was to assess stress using EEG-based variables obtained from univariate analysis and functional connectivity evaluation. Two different stressors, the Stroop test and sleep deprivation, were applied to 30 volunteers to find common EEG patterns related to stress effects. Results showed a decrease of the high alpha power (11 to 12 Hz), an increase in the high beta band (23 to 36 Hz, considered a busy brain indicator), and a decrease in the approximate entropy. Moreover, connectivity showed that the high beta coherence and the interhemispheric nonlinear couplings, measured by the cross mutual information function, increased significantly for both stressors, suggesting that useful stress indexes may be obtained from EEG-based features.

The relationship between psychosocial features of emerging adulthood and substance use change motivation in youth.

PubMed

Goodman, Ilana; Henderson, Joanna; Peterson-Badali, Michele; Goldstein, Abby L

2015-05-01

Despite the peak prevalence of substance use and comorbid mental health problems during emerging adulthood little research has focused on understanding behavior change processes during this transitional period. This study extended Arnett's (2004) theory of the psychosocial features of emerging adulthood to explore how they may relate to treatment motivation (e.g., readiness to comply with treatment) and motivation to change (e.g., problem recognition and taking steps towards change). One hundred sixty-four youth presenting to outpatient substance abuse treatment completed questionnaires investigating problematic substance use, mental health, psychosocial features of emerging adulthood and motivation. Results of hierarchical regression analyses indicated that youth who perceived themselves as having greater responsibility towards others were more intrinsically motivated, recognized their substance use as problematic and were taking steps towards change. None of the other dimensions of emerging adulthood accounted for significant variance beyond relevant controls. Limitations, directions for future research and treatment implications are discussed. Copyright © 2015 Elsevier Inc. All rights reserved.

Large-scale Topographical Screen for Investigation of Physical Neural-Guidance Cues

NASA Astrophysics Data System (ADS)

Li, Wei; Tang, Qing Yuan; Jadhav, Amol D.; Narang, Ankit; Qian, Wei Xian; Shi, Peng; Pang, Stella W.

2015-03-01

A combinatorial approach was used to present primary neurons with a large library of topographical features in the form of micropatterned substrate for high-throughput screening of physical neural-guidance cues that can effectively promote different aspects of neuronal development, including axon and dendritic outgrowth. Notably, the neuronal-guidance capability of specific features was automatically identified using a customized image processing software, thus significantly increasing the screening throughput with minimal subjective bias. Our results indicate that the anisotropic topographies promote axonal and in some cases dendritic extension relative to the isotropic topographies, while dendritic branching showed preference to plain substrates over the microscale features. The results from this work can be readily applied towards engineering novel biomaterials with precise surface topography that can serve as guidance conduits for neuro-regenerative applications. This novel topographical screening strategy combined with the automated processing capability can also be used for high-throughput screening of chemical or genetic regulatory factors in primary neurons.

Identifying predictive features in drug response using machine learning: opportunities and challenges.

PubMed

Vidyasagar, Mathukumalli

2015-01-01

This article reviews several techniques from machine learning that can be used to study the problem of identifying a small number of features, from among tens of thousands of measured features, that can accurately predict a drug response. Prediction problems are divided into two categories: sparse classification and sparse regression. In classification, the clinical parameter to be predicted is binary, whereas in regression, the parameter is a real number. Well-known methods for both classes of problems are briefly discussed. These include the SVM (support vector machine) for classification and various algorithms such as ridge regression, LASSO (least absolute shrinkage and selection operator), and EN (elastic net) for regression. In addition, several well-established methods that do not directly fall into machine learning theory are also reviewed, including neural networks, PAM (pattern analysis for microarrays), SAM (significance analysis for microarrays), GSEA (gene set enrichment analysis), and k-means clustering. Several references indicative of the application of these methods to cancer biology are discussed.

An evaluation of the suitability of ERTS data for the purposes of petroleum exploration. [lithology and geological structure of Anadarko Basin of Oklahoma and Texas

NASA Technical Reports Server (NTRS)

Collins, R. J. (Principal Investigator); Mccown, F. P.; Stonis, L. P.; Petzel, G. J.; Everett, J. R.

1974-01-01

The author has identified the following significant results. ERTS-1 data give exploration geologists a new perspective for looking at the earth. The data are excellent for interpreting regional lithologic and structural relationships and quickly directing attention to areas of greatest exploration interest. Information derived from ERTS data useful for petroleum exploration include: linear features, general lithologic distribution, identification of various anomalous features, some details of structures controlling hydrocarbon accumulation, overall structural relationships, and the regional context of the exploration province. Many anomalies (particularly geomorphic anomalies) correlate with known features of petroleum exploration interest. Linears interpreted from the imagery that were checked in the field correlate with fractures. Bands 5 and 7 and color composite imagery acquired during the periods of maximum and minimum vegetation vigor are best for geologic interpretation. Preliminary analysis indicates that use of ERTS imagery can substantially reduce the cost of petroleum exploration in relatively unexplored areas.

BRIEF REPORT: Beyond Clinical Experience: Features of Data Collection and Interpretation That Contribute to Diagnostic Accuracy

PubMed Central

Nendaz, Mathieu R; Gut, Anne M; Perrier, Arnaud; Louis-Simonet, Martine; Blondon-Choa, Katherine; Herrmann, François R; Junod, Alain F; Vu, Nu V

2006-01-01

BACKGROUND Clinical experience, features of data collection process, or both, affect diagnostic accuracy, but their respective role is unclear. OBJECTIVE, DESIGN Prospective, observational study, to determine the respective contribution of clinical experience and data collection features to diagnostic accuracy. METHODS Six Internists, 6 second year internal medicine residents, and 6 senior medical students worked up the same 7 cases with a standardized patient. Each encounter was audiotaped and immediately assessed by the subjects who indicated the reasons underlying their data collection. We analyzed the encounters according to diagnostic accuracy, information collected, organ systems explored, diagnoses evaluated, and final decisions made, and we determined predictors of diagnostic accuracy by logistic regression models. RESULTS Several features significantly predicted diagnostic accuracy after correction for clinical experience: early exploration of correct diagnosis (odds ratio [OR] 24.35) or of relevant diagnostic hypotheses (OR 2.22) to frame clinical data collection, larger number of diagnostic hypotheses evaluated (OR 1.08), and collection of relevant clinical data (OR 1.19). CONCLUSION Some features of data collection and interpretation are related to diagnostic accuracy beyond clinical experience and should be explicitly included in clinical training and modeled by clinical teachers. Thoroughness in data collection should not be considered a privileged way to diagnostic success. PMID:17105525

Variability In Long-Wave Runup as a Function of Nearshore Bathymetric Features

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dunkin, Lauren McNeill

Beaches and barrier islands are vulnerable to extreme storm events, such as hurricanes, that can cause severe erosion and overwash to the system. Having dunes and a wide beach in front of coastal infrastructure can provide protection during a storm, but the influence that nearshore bathymetric features have in protecting the beach and barrier island system is not completely understood. The spatial variation in nearshore features, such as sand bars and beach cusps, can alter nearshore hydrodynamics, including wave setup and runup. The influence of bathymetric features on long-wave runup can be used in evaluating the vulnerability of coastal regionsmore » to erosion and dune overtopping, evaluating the changing morphology, and implementing plans to protect infrastructure. In this thesis, long-wave runup variation due to changing bathymetric features as determined with the numerical model XBeach is quantified (eXtreme Beach behavior model). Wave heights are analyzed to determine the energy through the surfzone. XBeach assumes that coastal erosion at the land-sea interface is dominated by bound long-wave processes. Several hydrodynamic conditions are used to force the numerical model. The XBeach simulation results suggest that bathymetric irregularity induces significant changes in the extreme long-wave runup at the beach and the energy indicator through the surfzone.« less

SSVEP recognition using common feature analysis in brain-computer interface.

PubMed

Zhang, Yu; Zhou, Guoxu; Jin, Jing; Wang, Xingyu; Cichocki, Andrzej

2015-04-15

Canonical correlation analysis (CCA) has been successfully applied to steady-state visual evoked potential (SSVEP) recognition for brain-computer interface (BCI) application. Although the CCA method outperforms the traditional power spectral density analysis through multi-channel detection, it requires additionally pre-constructed reference signals of sine-cosine waves. It is likely to encounter overfitting in using a short time window since the reference signals include no features from training data. We consider that a group of electroencephalogram (EEG) data trials recorded at a certain stimulus frequency on a same subject should share some common features that may bear the real SSVEP characteristics. This study therefore proposes a common feature analysis (CFA)-based method to exploit the latent common features as natural reference signals in using correlation analysis for SSVEP recognition. Good performance of the CFA method for SSVEP recognition is validated with EEG data recorded from ten healthy subjects, in contrast to CCA and a multiway extension of CCA (MCCA). Experimental results indicate that the CFA method significantly outperformed the CCA and the MCCA methods for SSVEP recognition in using a short time window (i.e., less than 1s). The superiority of the proposed CFA method suggests it is promising for the development of a real-time SSVEP-based BCI. Copyright © 2014 Elsevier B.V. All rights reserved.

Diagnosing Autism Spectrum Disorder from Brain Resting-State Functional Connectivity Patterns Using a Deep Neural Network with a Novel Feature Selection Method

PubMed Central

Guo, Xinyu; Dominick, Kelli C.; Minai, Ali A.; Li, Hailong; Erickson, Craig A.; Lu, Long J.

2017-01-01

The whole-brain functional connectivity (FC) pattern obtained from resting-state functional magnetic resonance imaging data are commonly applied to study neuropsychiatric conditions such as autism spectrum disorder (ASD) by using different machine learning models. Recent studies indicate that both hyper- and hypo- aberrant ASD-associated FCs were widely distributed throughout the entire brain rather than only in some specific brain regions. Deep neural networks (DNN) with multiple hidden layers have shown the ability to systematically extract lower-to-higher level information from high dimensional data across a series of neural hidden layers, significantly improving classification accuracy for such data. In this study, a DNN with a novel feature selection method (DNN-FS) is developed for the high dimensional whole-brain resting-state FC pattern classification of ASD patients vs. typical development (TD) controls. The feature selection method is able to help the DNN generate low dimensional high-quality representations of the whole-brain FC patterns by selecting features with high discriminating power from multiple trained sparse auto-encoders. For the comparison, a DNN without the feature selection method (DNN-woFS) is developed, and both of them are tested with different architectures (i.e., with different numbers of hidden layers/nodes). Results show that the best classification accuracy of 86.36% is generated by the DNN-FS approach with 3 hidden layers and 150 hidden nodes (3/150). Remarkably, DNN-FS outperforms DNN-woFS for all architectures studied. The most significant accuracy improvement was 9.09% with the 3/150 architecture. The method also outperforms other feature selection methods, e.g., two sample t-test and elastic net. In addition to improving the classification accuracy, a Fisher's score-based biomarker identification method based on the DNN is also developed, and used to identify 32 FCs related to ASD. These FCs come from or cross different pre-defined brain networks including the default-mode, cingulo-opercular, frontal-parietal, and cerebellum. Thirteen of them are statically significant between ASD and TD groups (two sample t-test p < 0.05) while 19 of them are not. The relationship between the statically significant FCs and the corresponding ASD behavior symptoms is discussed based on the literature and clinician's expert knowledge. Meanwhile, the potential reason of obtaining 19 FCs which are not statistically significant is also provided. PMID:28871217

Quantitative diffusion weighted imaging parameters in tumor and peritumoral stroma for prediction of molecular subtypes in breast cancer

NASA Astrophysics Data System (ADS)

He, Ting; Fan, Ming; Zhang, Peng; Li, Hui; Zhang, Juan; Shao, Guoliang; Li, Lihua

2018-03-01

Breast cancer can be classified into four molecular subtypes of Luminal A, Luminal B, HER2 and Basal-like, which have significant differences in treatment and survival outcomes. We in this study aim to predict immunohistochemistry (IHC) determined molecular subtypes of breast cancer using image features derived from tumor and peritumoral stroma region based on diffusion weighted imaging (DWI). A dataset of 126 breast cancer patients were collected who underwent preoperative breast MRI with a 3T scanner. The apparent diffusion coefficients (ADCs) were recorded from DWI, and breast image was segmented into regions comprising the tumor and the surrounding stromal. Statistical characteristics in various breast tumor and peritumoral regions were computed, including mean, minimum, maximum, variance, interquartile range, range, skewness, and kurtosis of ADC values. Additionally, the difference of features between each two regions were also calculated. The univariate logistic based classifier was performed for evaluating the performance of the individual features for discriminating subtypes. For multi-class classification, multivariate logistic regression model was trained and validated. The results showed that the tumor boundary and proximal peritumoral stroma region derived features have a higher performance in classification compared to that of the other regions. Furthermore, the prediction model using statistical features, difference features and all the features combined from these regions generated AUC values of 0.774, 0.796 and 0.811, respectively. The results in this study indicate that ADC feature in tumor and peritumoral stromal region would be valuable for estimating the molecular subtype in breast cancer.

Looking at faces from different angles: Europeans fixate different features in Asian and Caucasian faces.

PubMed

Brielmann, Aenne A; Bülthoff, Isabelle; Armann, Regine

2014-07-01

Race categorization of faces is a fast and automatic process and is known to affect further face processing profoundly and at earliest stages. Whether processing of own- and other-race faces might rely on different facial cues, as indicated by diverging viewing behavior, is much under debate. We therefore aimed to investigate two open questions in our study: (1) Do observers consider information from distinct facial features informative for race categorization or do they prefer to gain global face information by fixating the geometrical center of the face? (2) Does the fixation pattern, or, if facial features are considered relevant, do these features differ between own- and other-race faces? We used eye tracking to test where European observers look when viewing Asian and Caucasian faces in a race categorization task. Importantly, in order to disentangle centrally located fixations from those towards individual facial features, we presented faces in frontal, half-profile and profile views. We found that observers showed no general bias towards looking at the geometrical center of faces, but rather directed their first fixations towards distinct facial features, regardless of face race. However, participants looked at the eyes more often in Caucasian faces than in Asian faces, and there were significantly more fixations to the nose for Asian compared to Caucasian faces. Thus, observers rely on information from distinct facial features rather than facial information gained by centrally fixating the face. To what extent specific features are looked at is determined by the face's race. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

[Spectral features analysis of sea ice in the Arctic Ocean].

PubMed

Ke, Chang-qing; Xie, Hong-jie; Lei, Rui-bo; Li, Qun; Sun, Bo

2012-04-01

Sea ice in the Arctic Ocean plays an important role in the global climate change, and its quick change and impact are the scientists' focus all over the world. The spectra of different kinds of sea ice were measured with portable ASD FieldSpec 3 spectrometer during the long-term ice station of the 4th Chinese national Arctic Expedition in 2010, and the spectral features were analyzed systematically. The results indicated that the reflectance of sea ice covered by snow is the highest one, naked sea ice the second, and melted sea ice the lowest. Peak and valley characteristics of spectrum curves of sea ice covered by thick snow, thin snow, wet snow and snow crystal are very significant, and the reflectance basically decreases with the wavelength increasing. The rules of reflectance change with wavelength of natural sea ice, white ice and blue ice are basically same, the reflectance of them is medium, and that of grey ice is far lower than natural sea ice, white ice and blue ice. It is very significant for scientific research to analyze the spectral features of sea ice in the Arctic Ocean and to implement the quantitative remote sensing of sea ice, and to further analyze its response to the global warming.

Surface cytologic features on intraocular lenses: can increased biocompatibility have disadvantages?

PubMed

Hollick, E J; Spalton, D J; Ursell, P G

1999-07-01

To compare the anterior surface cytologic features and effect on blood-aqueous barrier of polymethyl methacrylate, silicone, and hydrogel intraocular lens (IOL) implants to give an indication of their biocompatibility. This prospective study was performed at an English-teaching hospital. Ninety eyes were randomized to receive a polymethyl methacrylate, silicone, or hydrogel implant. A standardized surgical protocol was performed by a single surgeon using phacoemulsification. Patients were seen at intervals for 1 year. Measurements of visual acuity, contrast sensitivity, and anterior chamber laser flare and cells were obtained; and an assessment of lens cytologic features using specular microscopy of the anterior IOL surface was performed. Visual acuity and contrast sensitivity were not significantly different among the 3 groups. Hydrogel IOLs were associated with fewer inflammatory cells on their surface than polymethyl methacrylate and silicone IOLs (P<.001), but with significantly more lens epithelial cells (LECs) (P<.001). Patients with hydrogel implants without LECs had greater blood-aqueous barrier breakdown than those with LECs. The hydrogel IOLs were associated with a reduced inflammatory cell reaction but had many more LECs on their anterior surface. Those IOLs associated with increased blood-aqueous barrier damage did not develop LECs. If an IOL is too biocompatible, then it may incite the growth of LECs over its surface, which could have disadvantages.

Biomass enzymatic saccharification is determined by the non-KOH-extractable wall polymer features that predominately affect cellulose crystallinity in corn.

PubMed

Jia, Jun; Yu, Bin; Wu, Leiming; Wang, Hongwu; Wu, Zhiliang; Li, Ming; Huang, Pengyan; Feng, Shengqiu; Chen, Peng; Zheng, Yonglian; Peng, Liangcai

2014-01-01

Corn is a major food crop with enormous biomass residues for biofuel production. Due to cell wall recalcitrance, it becomes essential to identify the key factors of lignocellulose on biomass saccharification. In this study, we examined total 40 corn accessions that displayed a diverse cell wall composition. Correlation analysis showed that cellulose and lignin levels negatively affected biomass digestibility after NaOH pretreatments at p<0.05 & 0.01, but hemicelluloses did not show any significant impact on hexoses yields. Comparative analysis of five standard pairs of corn samples indicated that cellulose and lignin should not be the major factors on biomass saccharification after pretreatments with NaOH and H2SO4 at three concentrations. Notably, despite that the non-KOH-extractable residues covered 12%-23% hemicelluloses and lignin of total biomass, their wall polymer features exhibited the predominant effects on biomass enzymatic hydrolysis including Ara substitution degree of xylan (reverse Xyl/Ara) and S/G ratio of lignin. Furthermore, the non-KOH-extractable polymer features could significantly affect lignocellulose crystallinity at p<0.05, leading to a high biomass digestibility. Hence, this study could suggest an optimal approach for genetic modification of plant cell walls in bioenergy corn.

Spectral characteristics of the iron oxides with application to the Martian bright region mineralogy

NASA Technical Reports Server (NTRS)

Sherman, D. M.; Burns, R. G.; Mee Burns, V.

1982-01-01

Reflectance spectra of eight polymorphs of FeOOH and Fe2O3 are determined in order to clarify the nature and significance of the iron oxide mineralogy on Mars. The effect of other components that might interfere with iron oxide absorption features is qualitatively constrained through the use of the Kebulka-Munk theory. It is found that the effect of temperature complicates the identification of a given Fe(3+) phase based on the position of the 6A1-4T1 absorption feature. While the Fe(3+) crystal field transitions are spin forbidden, most of the iron oxide polymorphs exhibit anomalously intense crystal field absorption features due to magnetic coupling between adjacent FeO6 octahedra. It is suggested that the resulting deviations from observed remotely sensed reflectance spectra of Mars may provide a basis for the exclusion of many iron oxide phases as significant components of the Martian Fe(3+) mineralogy. A comparison of these results with the visible region spectra of Martian bright regions indicates that the predominant Fe(3+)-bearing phase may be a magnetically disordered material, such as amorphous gels, some ferric sulphates, and other minerals in which Fe(3+) ions in the crystal structure are not magnetically coupled.

Clinical value of the neutrophil/lymphocyte ratio in diagnosing adult strangulated inguinal hernia.

PubMed

Zhou, Huanhao; Ruan, Xiaojiao; Shao, Xia; Huang, Xiaming; Fang, Guan; Zheng, Xiaofeng

2016-12-01

Diagnosis of incarcerated inguinal hernia (IIH) is not difficult, but currently, there are no diagnostic criteria that can be used to differentiate it from strangulated inguinal hernia (SIH). This research aimed to evaluate the clinical value of the neutrophil/lymphocyte ratio (NLR) in diagnosing SIH. We retrospectively analyzed 263 patients with IIH who had undergone emergency operation. The patients were divided into two groups according to IIH severity: group A, patients with pure IIH validated during operation as having no bowel ischemia; group B, patients with SIH validated during operation as having obvious bowel ischemia, including bowel necrosis. We statistically evaluated the relation between several clinical features and SIH. The accuracy of different indices was then evaluated and compared using receiver operating characteristic (ROC) curve analyses, and the corresponding cutoff values were calculated. Univariate analysis showed eight clinical features that were significantly different between the two groups. They were then subjected to multivariate analysis, which showed that the NLR, type of hernia, and incarcerated organ were significantly related to SIH. ROC curve analysis showed that the NLR had the largest area under the ROC curve. Among the different clinical features, the NLR appears to be the best index in diagnosing SIH. Copyright © 2016 IJS Publishing Group Ltd. Published by Elsevier Ltd. All rights reserved.

Modeling the development of martian sublimation thermokarst landforms

USGS Publications Warehouse

Dundas, Colin M.; Byrne, Shane; McEwen, Alfred S.

2015-01-01

Sublimation-thermokarst landforms result from collapse of the surface when ice is lost from the subsurface. On Mars, scalloped landforms with scales of decameters to kilometers are observed in the mid-latitudes and considered likely thermokarst features. We describe a landscape evolution model that couples diffusive mass movement and subsurface ice loss due to sublimation. Over periods of tens of thousands of Mars years under conditions similar to the present, the model produces scallop-like features similar to those on the Martian surface, starting from much smaller initial disturbances. The model also indicates crater expansion when impacts occur in surfaces underlain by excess ice to some depth, with morphologies similar to observed landforms on the Martian northern plains. In order to produce these landforms by sublimation, substantial quantities of excess ice are required, at least comparable to the vertical extent of the landform, and such ice must remain in adjacent terrain to support the non-deflated surface. We suggest that Martian thermokarst features are consistent with formation by sublimation, without melting, and that significant thicknesses of very clean excess ice (up to many tens of meters, the depth of some scalloped depressions) are locally present in the Martian mid-latitudes. Climate conditions leading to melting at significant depth are not required.

Childhood and Current Autistic Features in Adolescents with Schizotypal Personality Disorder

PubMed Central

Esterberg, Michelle L.; Trotman, Hanan D.; Brasfield, Joy L.; Compton, Michael T.; Walker, Elaine F.

2008-01-01

The diagnostic boundaries between autistic- and schizophrenia-spectrum disorders have varied over the years, and some overlap in diagnostic criteria persists. The present study examined childhood and current signs of autistic disorder (AD) in adolescents with schizotypal personality disorder (SPD) or other personality disorders, as well as healthy controls. A structured interview was administered to rate participants’ current symptoms. Participants’ guardians were interviewed with the Autism Diagnostic Inventory-Revised (ADI-R), a clinical assessment of childhood and current autistic signs. Compared to both the other personality-disordered and healthy groups, adolescents with SPD were rated as having significantly more impairment on childhood and current social functioning, and having more unusual interests and behaviors. For the entire sample, impaired childhood social functioning and unusual interests and behaviors were associated with higher negative symptom scores. Current impairments in social functioning, unusual interests and behaviors, and communication were also linked with greater negative symptoms. However, neither childhood nor current autistic features significantly predicted later conversion to an Axis I psychotic disorder over the course of three years of follow-up. The findings indicate that past and current autistic signs are more common in adolescents with SPD, but neither current nor childhood autistic features are linked with conversion to psychosis. PMID:18554872

Feature Extraction and Classification of EHG between Pregnancy and Labour Group Using Hilbert-Huang Transform and Extreme Learning Machine.

PubMed

Chen, Lili; Hao, Yaru

2017-01-01

Preterm birth (PTB) is the leading cause of perinatal mortality and long-term morbidity, which results in significant health and economic problems. The early detection of PTB has great significance for its prevention. The electrohysterogram (EHG) related to uterine contraction is a noninvasive, real-time, and automatic novel technology which can be used to detect, diagnose, or predict PTB. This paper presents a method for feature extraction and classification of EHG between pregnancy and labour group, based on Hilbert-Huang transform (HHT) and extreme learning machine (ELM). For each sample, each channel was decomposed into a set of intrinsic mode functions (IMFs) using empirical mode decomposition (EMD). Then, the Hilbert transform was applied to IMF to obtain analytic function. The maximum amplitude of analytic function was extracted as feature. The identification model was constructed based on ELM. Experimental results reveal that the best classification performance of the proposed method can reach an accuracy of 88.00%, a sensitivity of 91.30%, and a specificity of 85.19%. The area under receiver operating characteristic (ROC) curve is 0.88. Finally, experimental results indicate that the method developed in this work could be effective in the classification of EHG between pregnancy and labour group.

Biomass Enzymatic Saccharification Is Determined by the Non-KOH-Extractable Wall Polymer Features That Predominately Affect Cellulose Crystallinity in Corn

PubMed Central

Wu, Leiming; Wang, Hongwu; Wu, Zhiliang; Li, Ming; Huang, Pengyan; Feng, Shengqiu; Chen, Peng; Zheng, Yonglian; Peng, Liangcai

2014-01-01

Corn is a major food crop with enormous biomass residues for biofuel production. Due to cell wall recalcitrance, it becomes essential to identify the key factors of lignocellulose on biomass saccharification. In this study, we examined total 40 corn accessions that displayed a diverse cell wall composition. Correlation analysis showed that cellulose and lignin levels negatively affected biomass digestibility after NaOH pretreatments at p<0.05 & 0.01, but hemicelluloses did not show any significant impact on hexoses yields. Comparative analysis of five standard pairs of corn samples indicated that cellulose and lignin should not be the major factors on biomass saccharification after pretreatments with NaOH and H2SO4 at three concentrations. Notably, despite that the non-KOH-extractable residues covered 12%–23% hemicelluloses and lignin of total biomass, their wall polymer features exhibited the predominant effects on biomass enzymatic hydrolysis including Ara substitution degree of xylan (reverse Xyl/Ara) and S/G ratio of lignin. Furthermore, the non-KOH-extractable polymer features could significantly affect lignocellulose crystallinity at p<0.05, leading to a high biomass digestibility. Hence, this study could suggest an optimal approach for genetic modification of plant cell walls in bioenergy corn. PMID:25251456

Identification of landscape features influencing gene flow: How useful are habitat selection models?

USGS Publications Warehouse

Roffler, Gretchen H.; Schwartz, Michael K.; Pilgrim, Kristy L.; Talbot, Sandra L.; Sage, Kevin; Adams, Layne G.; Luikart, Gordon

2016-01-01

Understanding how dispersal patterns are influenced by landscape heterogeneity is critical for modeling species connectivity. Resource selection function (RSF) models are increasingly used in landscape genetics approaches. However, because the ecological factors that drive habitat selection may be different from those influencing dispersal and gene flow, it is important to consider explicit assumptions and spatial scales of measurement. We calculated pairwise genetic distance among 301 Dall's sheep (Ovis dalli dalli) in southcentral Alaska using an intensive noninvasive sampling effort and 15 microsatellite loci. We used multiple regression of distance matrices to assess the correlation of pairwise genetic distance and landscape resistance derived from an RSF, and combinations of landscape features hypothesized to influence dispersal. Dall's sheep gene flow was positively correlated with steep slopes, moderate peak normalized difference vegetation indices (NDVI), and open land cover. Whereas RSF covariates were significant in predicting genetic distance, the RSF model itself was not significantly correlated with Dall's sheep gene flow, suggesting that certain habitat features important during summer (rugged terrain, mid-range elevation) were not influential to effective dispersal. This work underscores that consideration of both habitat selection and landscape genetics models may be useful in developing management strategies to both meet the immediate survival of a species and allow for long-term genetic connectivity.

Acoustic Features Influence Musical Choices Across Multiple Genres.

PubMed

Barone, Michael D; Bansal, Jotthi; Woolhouse, Matthew H

2017-01-01

Based on a large behavioral dataset of music downloads, two analyses investigate whether the acoustic features of listeners' preferred musical genres influence their choice of tracks within non-preferred, secondary musical styles. Analysis 1 identifies feature distributions for pairs of genre-defined subgroups that are distinct. Using correlation analysis, these distributions are used to test the degree of similarity between subgroups' main genres and the other music within their download collections. Analysis 2 explores the issue of main-to-secondary genre influence through the production of 10 feature-influence matrices, one per acoustic feature, in which cell values indicate the percentage change in features for genres and subgroups compared to overall population averages. In total, 10 acoustic features and 10 genre-defined subgroups are explored within the two analyses. Results strongly indicate that the acoustic features of people's main genres influence the tracks they download within non-preferred, secondary musical styles. The nature of this influence and its possible actuating mechanisms are discussed with respect to research on musical preference, personality, and statistical learning.

Sparse feature selection for classification and prediction of metastasis in endometrial cancer.

PubMed

Ahsen, Mehmet Eren; Boren, Todd P; Singh, Nitin K; Misganaw, Burook; Mutch, David G; Moore, Kathleen N; Backes, Floor J; McCourt, Carolyn K; Lea, Jayanthi S; Miller, David S; White, Michael A; Vidyasagar, Mathukumalli

2017-03-27

Metastasis via pelvic and/or para-aortic lymph nodes is a major risk factor for endometrial cancer. Lymph-node resection ameliorates risk but is associated with significant co-morbidities. Incidence in patients with stage I disease is 4-22% but no mechanism exists to accurately predict it. Therefore, national guidelines for primary staging surgery include pelvic and para-aortic lymph node dissection for all patients whose tumor exceeds 2cm in diameter. We sought to identify a robust molecular signature that can accurately classify risk of lymph node metastasis in endometrial cancer patients. 86 tumors matched for age and race, and evenly distributed between lymph node-positive and lymph node-negative cases, were selected as a training cohort. Genomic micro-RNA expression was profiled for each sample to serve as the predictive feature matrix. An independent set of 28 tumor samples was collected and similarly characterized to serve as a test cohort. A feature selection algorithm was designed for applications where the number of samples is far smaller than the number of measured features per sample. A predictive miRNA expression signature was developed using this algorithm, which was then used to predict the metastatic status of the independent test cohort. A weighted classifier, using 18 micro-RNAs, achieved 100% accuracy on the training cohort. When applied to the testing cohort, the classifier correctly predicted 90% of node-positive cases, and 80% of node-negative cases (FDR = 6.25%). Results indicate that the evaluation of the quantitative sparse-feature classifier proposed here in clinical trials may lead to significant improvement in the prediction of lymphatic metastases in endometrial cancer patients.

TU-G-204-05: The Effects of CT Acquisition and Reconstruction Conditions On Computed Texture Feature Values of Lung Lesions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lo, P; Young, S; Kim, G

2015-06-15

Purpose: Texture features have been investigated as a biomarker of response and malignancy. Because these features reflect local differences in density, they may be influenced by acquisition and reconstruction parameters. The purpose of this study was to investigate the effects of radiation dose level and reconstruction method on features derived from lung lesions. Methods: With IRB approval, 33 lung tumor cases were identified from clinically indicated thoracic CT scans in which the raw projection (sinogram) data were available. Based on a previously-published technique, noise was added to the raw data to simulate reduced-dose versions of each case at 25%, 10%more » and 3% of the original dose. Original and simulated reduced dose projection data were reconstructed with conventional and two iterative-reconstruction settings, yielding 12 combinations of dose/recon conditions. One lesion from each case was contoured. At the reference condition (full dose, conventional recon), 17 lesions were randomly selected for repeat contouring (repeatability). For each lesion at each dose/recon condition, 151 texture measures were calculated. A paired differences approach was employed to compare feature variation from repeat contours at the reference condition to the variation observed in other dose/recon conditions (reproducibility). The ratio of standard deviation of the reproducibility to repeatability was used as the variation measure for each feature. Results: The mean variation (standard deviation) across dose levels and kernel was significantly different with a ratio of 2.24 (±5.85) across texture features (p=0.01). The mean variation (standard deviation) across dose levels with conventional recon was also significantly different with 2.30 (7.11) (p=0.025). The mean variation across reconstruction settings of original dose has a trend in showing difference with 1.35 (2.60) among all features (p=0.09). Conclusion: Texture features varied considerably with variations in dose and reconstruction condition. Care should be taken to standardize these conditions when using texture as a quantitative feature. This effort supported in part by a grant from the National Cancer Institute’s Quantitative Imaging Network (QIN): U01 CA181156; The UCLA Department of Radiology has a Master Research Agreement with Siemens Healthcare; Dr. McNitt-Gray has previously received research support from Siemens Healthcare.« less

Ground-based observation of the cyclic nature and temporal variability of planetary-scale UV features at the Venus cloud top level

NASA Astrophysics Data System (ADS)

Imai, Masataka; Takahashi, Yukihiro; Watanabe, Makoto; Kouyama, Toru; Watanabe, Shigeto; Gouda, Shuhei; Gouda, Yuya

2016-11-01

A planetary-scale bright and dark UV feature, known as the ;Y-feature,; rotates around Venus with a period of 4-5 days and has been long-time interpreted as planetary waves. When assuming this, its rotation period and spatial structure might help to understand the propagation of the planetary-scale waves and find out their role in the acceleration-deceleration of the zonal wind speed, which is essential for understanding the super-rotation of the planet. The rotation period of the UV feature varied over the course of observation by the Pioneer Venus orbiter. However, in previous explorations of Venus such as Pioneer Venus and Venus Express, the spacecraft were operated in nearly fixed inertial space. As a result, the periodicity variations on sub-yearly timescales (one Venusian year is ∼224 Earth days) were obscured by the limitations of continuous dayside observations. We newly conducted six periods of ground-based Venus imaging observations at 365 nm from mid-August 2013 to the end of June 2014. Each observation period spanned over half or one month, enabling long-term monitoring of Venus' atmosphere above the equator region. Distributions of the relative brightness were obtained from the equatorial (EQ) to mid-latitudinal regions in both hemispheres, and from the cyclical variations of these distributions we deduced the rotation periods of the UV features of the cloud tops brightness. The relative brightness exhibited periods of 5.2 and 3.5 days above 90% of significance. The relative intensities of these two significant components also seemed subject to temporal variations. Although the 3.5-day component considered persists throughout the observation periods, its dominance over the longer period varied in a cyclic fashion. The prevailing first significant mode seems to change from 5.2-day waves to 3.5-day waves in about nine months, which is clearly inconsistent with the Venusian year. Clear periodic perturbations, indicating stability of the planetary-scale UV-feature, were observed only in the presence of single longer or shorter periodic waves. During the transition periods of dominant-wave changing, the amplitude of the relative brightness was largely changed. This can be explained by the deformation of the Y-shaped UV feature as observed by Pioneer Venus in 1979.

Visual acuity of the honey bee retina and the limits for feature detection.

PubMed

Rigosi, Elisa; Wiederman, Steven D; O'Carroll, David C

2017-04-06

Visual abilities of the honey bee have been studied for more than 100 years, recently revealing unexpectedly sophisticated cognitive skills rivalling those of vertebrates. However, the physiological limits of the honey bee eye have been largely unaddressed and only studied in an unnatural, dark state. Using a bright display and intracellular recordings, we here systematically investigated the angular sensitivity across the light adapted eye of honey bee foragers. Angular sensitivity is a measure of photoreceptor receptive field size and thus small values indicate higher visual acuity. Our recordings reveal a fronto-ventral acute zone in which angular sensitivity falls below 1.9°, some 30% smaller than previously reported. By measuring receptor noise and responses to moving dark objects, we also obtained direct measures of the smallest features detectable by the retina. In the frontal eye, single photoreceptors respond to objects as small as 0.6° × 0.6°, with >99% reliability. This indicates that honey bee foragers possess significantly better resolution than previously reported or estimated behaviourally, and commonly assumed in modelling of bee acuity.

Photosynthetic Mediterranean meadow orchids feature partial mycoheterotrophy and specific mycorrhizal associations.

PubMed

Girlanda, Mariangela; Segreto, Rossana; Cafasso, Donata; Liebel, Heiko Tobias; Rodda, Michele; Ercole, Enrico; Cozzolino, Salvatore; Gebauer, Gerhard; Perotto, Silvia

2011-07-01

We investigated whether four widespread, photosynthetic Mediterranean meadow orchids (Ophrys fuciflora, Anacamptis laxiflora, Orchis purpurea, and Serapias vomeracea) had either nutritional dependency on mycobionts or mycorrhizal fungal specificity. Nonphotosynthetic orchids generally engage in highly specific interactions with fungal symbionts that provide them with organic carbon. By contrast, fully photosynthetic orchids in sunny, meadow habitats have been considered to lack mycorrhizal specificity. We performed both culture-dependent and culture-independent ITS sequence analysis to identify fungi from orchid roots. By analyzing stable isotope ((13)C and (15)N) natural abundances, we also determined the degree of autotrophy and mycoheterotrophy in the four orchid species. Phylogenetic and multivariate comparisons indicated that Or. purpurea and Oph. fuciflora featured lower fungal diversity and more specific mycobiont spectra than A. laxiflora and S. vomeracea. All orchid species were significantly enriched in (15)N compared with neighboring non-orchid plants. Orchis purpurea had the most pronounced N gain from fungi and differed from the other orchids in also obtaining C from fungi. These results indicated that even in sunny Mediterranean meadows, orchids may be mycoheterotrophic, with correlated mycorrhizal fungal specificity.

Mean platelet volume is elevated in patients with patent foramen ovale.

PubMed

Demir, Bulent; Caglar, Ilker Murat; Ungan, Ismail; Ugurlucan, Murat; Tureli, Hande Oktay; Karakaya, Osman

2013-12-30

Platelets play a major role in thromboembolic events. Increased mean platelet volume (MPV) indicates higher platelet reactivity and also a tendency to thrombosis. Patent foramen ovale (PFO), persistence of the fetal anatomic shunt between right and left atria, is strongly associated with cryptogenic stroke. The aim of this study is to determine the relationship between MPV and PFO and if such an association exists, whether higher MPV levels may require antiplatelet therapy before a thromboembolic event happens, together with a literature review. Thirty patients (15 women, 15 men), free of any cerebrovascular events, were diagnosed with PFO by transesophageal echocardiography (TEE), enrolled as the study group. Thirty consecutive patients (16 women and 14 men), who were diagnosed as normal in TEE, were enrolled as the control group. These two groups were compared according to MPV and anatomical features of the right atrium. There was no significant difference between study and control groups in clinical features and also no difference was observed in platelet counts; however, MPV in the PFO group was significantly higher than the control group (8.38 ±0.93 fl and 7.45 ±0.68 fl respectively). Our results indicate that elevated MPV may be detected in patients with PFO. This might be one of the explanations for the relationship between PFO and cryptogenic stroke; however, larger cohorts are warranted in order to define further mechanisms.

Imaging features of TSCT predict the classification of pulmonary preinvasive lesion, minimally and invasive adenocarcinoma presented as ground glass nodules.

PubMed

Liu, Yinan; Sun, Hui; Zhou, Fei; Su, Chunxia; Gao, Guanghui; Ren, Shengxiang; Zhou, Caicun; Zhang, Zhemin; Shi, Jingyun

2017-06-01

To comprehensively investigate the role of thin section computed tomography(TSCT) features to distinguish invasive adenocarcinoma(IA) from preinvasive or minimally invasive adenocarcinoma(MIA) appearing as pure or mixed ground glass nodules (pGGNs, mGGNs), and to distinguish adenocarcinoma in situ (AIS) from atypical adenomatous hyperplasia (AAH) in pGGNs. Three hundred thirteen patients with 334 pathologically diagnosed GGNs according to the 2011 IASLC/ATS/ERS classification were included into this study. The TSCT features of the AAH-MIAs and IAs were compared and analyzed respectively in pGGNs (158 cases) and mGGNs (176 cases). Additionally, AIS (30 cases) and AAH (33 cases) were further analyzed in pGGNs. Receiver operating characteristic(ROC) analysis were performed to determine the cutoff values for the qualitative variables and their diagnostic performances. In pGGNs, significant differences were found in the tumor volume(p=0.017, OR=4.98, 95%CI 1.33-18.62) and tumor mass(p=0.03, OR=5.04, 95%CI 1.17-21.59) between AAH-MIAs (AAH, AIS, MIA) group and IAs group, and tumor mass(p=0.037, OR=4.32, 95%CI 1.09-17.10) and standard deviation(SD) (p=0.019, OR=13.92, 95%CI 1.53-126.57) could distinguish AIS from AAH. In mGGNs, significant differences were found in consolidation size (p=0.006, OR=21.98, 95%CI 2.46-196.67) and consolidation mean CT value (p=0.011, OR=18.20, 95%CI1.96-168.88) between AAH-MIAs group and IAs group. Multivariate and ROC analyses revealed that in pGGNs, tumor size (≥1125mm) and mass (>386) were significantly associated with IAs. SD (≥68) and mass (≥70) were significant in distinguishing AIS from AAH. Larger consolidation of nodules (≥8.1mm) and higher CT values of the solid components (≥-222 HU) in mGGNs were significantly associated with IAs. TSCT features can help distinguish IAs from AAH-MIAs both in pGGNs and mGGNs, and identify AIS from AAH in pGGNs, which indicated that imaging features may be helpful to guide the therapeutic choice for patients with GGNs which were considered as high risk of malignant diseases. Copyright © 2017 Elsevier B.V. All rights reserved.

Medical image retrieval system using multiple features from 3D ROIs

NASA Astrophysics Data System (ADS)

Lu, Hongbing; Wang, Weiwei; Liao, Qimei; Zhang, Guopeng; Zhou, Zhiming

2012-02-01

Compared to a retrieval using global image features, features extracted from regions of interest (ROIs) that reflect distribution patterns of abnormalities would benefit more for content-based medical image retrieval (CBMIR) systems. Currently, most CBMIR systems have been designed for 2D ROIs, which cannot reflect 3D anatomical features and region distribution of lesions comprehensively. To further improve the accuracy of image retrieval, we proposed a retrieval method with 3D features including both geometric features such as Shape Index (SI) and Curvedness (CV) and texture features derived from 3D Gray Level Co-occurrence Matrix, which were extracted from 3D ROIs, based on our previous 2D medical images retrieval system. The system was evaluated with 20 volume CT datasets for colon polyp detection. Preliminary experiments indicated that the integration of morphological features with texture features could improve retrieval performance greatly. The retrieval result using features extracted from 3D ROIs accorded better with the diagnosis from optical colonoscopy than that based on features from 2D ROIs. With the test database of images, the average accuracy rate for 3D retrieval method was 76.6%, indicating its potential value in clinical application.

Change of the image of the city in process of using traffic infrastructure

NASA Astrophysics Data System (ADS)

Alihodžić, Rifat; Vasiljević Tomić, Dragana; Iablonskii, Leonid

2017-10-01

Unique urban image cannot be experienced without moving within its structure. This paper deals with phenomenology considering changes of images of the city and influential factors closely related to it. Infrastructure gives basic structural scheme of every city, so its planning requires a high level proficiency. Some changes in these images can be observed during longer period of time. Sometimes it includes rapid changes of temporal layers, generated by building new urban elements on the exact same place where the old ones existed; while lighter change during the time passing is a regular occurrence. Creating completely new urban frames, caused by expanding the city, represents its dynamical variant. Topography is a significant factor, giving distinctive feature to the urbanity. This paper considers factors identified as generators of the change of the urban image, based on research so far. The structural elements are considered with the utmost attention. The importance of the city landmark, monumental complexes not possessing these features but having the importance in image of the city stability (as well as the inhabitants’ memory) are crucial elements of identifying its picture. Another significant factor is related to individual personal experience. However, there are also certain factors of significance features, but not considered within this paper. One such factor is change in coloring, being the special topic itself. The purpose of this work is to indicate that urban planning requires special attention in order to keep continuous nature of the urban image for the city to preserve its visual identity.

Tidal interaction, star formation and chemical evolution in blue compact dwarf galaxy Mrk 22

NASA Astrophysics Data System (ADS)

Paswan, A.; Omar, A.; Jaiswal, S.

2018-02-01

The optical spectroscopic and radio interferometric H I 21 cm-line observations of the blue compact dwarf galaxy Mrk 22 are presented. The Wolf-Rayet (WR) emission-line features corresponding to high ionization lines of He II λ4686 and C IV λ5808 from young massive stars are detected. The ages of two prominent star-forming regions in the galaxy are estimated as ∼10 and ∼ 4 Myr. The galaxy has non-thermal radio deficiency, which also indicates a young starburst and lack of supernovae events from the current star formation activities, consistent with the detection of WR emission-line features. A significant N/O enrichment is seen in the fainter star-forming region. The gas-phase metallicities [12 + log(O/H)] for the bright and faint regions are estimated as 7.98±0.07 and 7.46±0.09, respectively. The galaxy has a large diffuse H I envelop. The H I images reveal disturbed gas kinematics and H I clouds outside the optical extent of the galaxy, indicating recent tidal interaction or merger in the system. The results strongly indicate that Mrk 22 is undergoing a chemical and morphological evolution due to ongoing star formation, most likely triggered by a merger.

Retrieval of spheroid particle size distribution from spectral extinction data in the independent mode using PCA approach

NASA Astrophysics Data System (ADS)

Tang, Hong; Lin, Jian-Zhong

2013-01-01

An improved anomalous diffraction approximation (ADA) method is presented for calculating the extinction efficiency of spheroids firstly. In this approach, the extinction efficiency of spheroid particles can be calculated with good accuracy and high efficiency in a wider size range by combining the Latimer method and the ADA theory, and this method can present a more general expression for calculating the extinction efficiency of spheroid particles with various complex refractive indices and aspect ratios. Meanwhile, the visible spectral extinction with varied spheroid particle size distributions and complex refractive indices is surveyed. Furthermore, a selection principle about the spectral extinction data is developed based on PCA (principle component analysis) of first derivative spectral extinction. By calculating the contribution rate of first derivative spectral extinction, the spectral extinction with more significant features can be selected as the input data, and those with less features is removed from the inversion data. In addition, we propose an improved Tikhonov iteration method to retrieve the spheroid particle size distributions in the independent mode. Simulation experiments indicate that the spheroid particle size distributions obtained with the proposed method coincide fairly well with the given distributions, and this inversion method provides a simple, reliable and efficient method to retrieve the spheroid particle size distributions from the spectral extinction data.

HMM-based lexicon-driven and lexicon-free word recognition for online handwritten Indic scripts.

PubMed

Bharath, A; Madhvanath, Sriganesh

2012-04-01

Research for recognizing online handwritten words in Indic scripts is at its early stages when compared to Latin and Oriental scripts. In this paper, we address this problem specifically for two major Indic scripts--Devanagari and Tamil. In contrast to previous approaches, the techniques we propose are largely data driven and script independent. We propose two different techniques for word recognition based on Hidden Markov Models (HMM): lexicon driven and lexicon free. The lexicon-driven technique models each word in the lexicon as a sequence of symbol HMMs according to a standard symbol writing order derived from the phonetic representation. The lexicon-free technique uses a novel Bag-of-Symbols representation of the handwritten word that is independent of symbol order and allows rapid pruning of the lexicon. On handwritten Devanagari word samples featuring both standard and nonstandard symbol writing orders, a combination of lexicon-driven and lexicon-free recognizers significantly outperforms either of them used in isolation. In contrast, most Tamil word samples feature the standard symbol order, and the lexicon-driven recognizer outperforms the lexicon free one as well as their combination. The best recognition accuracies obtained for 20,000 word lexicons are 87.13 percent for Devanagari when the two recognizers are combined, and 91.8 percent for Tamil using the lexicon-driven technique.

Interactions between natural-occurring landscape conditions and land use influencing the abundance of riverine smallmouth bass, micropterus dolomieu

USGS Publications Warehouse

Brewer, S.K.; Rabeni, C.F.

2011-01-01

This study examined how interactions between natural landscape features and land use influenced the abundance of smallmouth bass, Micropterus dolomieu, in Missouri, USA, streams. Stream segments were placed into one of four groups based on natural-occurring watershed characteristics (soil texture and soil permeability) predicted to relate to smallmouth bass abundance. Within each group, stream segments were assigned forest (n = 3), pasture (n = 3), or urban (n = 3) designations based on the percentages of land use within each watershed. Analyses of variance indicated smallmouth bass densities differed between land use and natural conditions. Decision tree models indicated abundance was highest in forested stream segments and lowest in urban stream segments, regardless of group designation. Land use explained the most variation in decision tree models, but in-channel features of temperature, flow, and sediment also contributed significantly. These results are unique and indicate the importance of natural-occurring watershed conditions in defining the potential of populations and how finer-scale filters interact with land use to further alter population potential. Smallmouth bass has differing vulnerabilities to land-use attributes, and the better the natural watershed conditions are for population success, the more resilient these populations will be when land conversion occurs.

Seismicity and structure of Akutan and Makushin Volcanoes, Alaska, using joint body and surface wave tomography

DOE PAGES

Syracuse, E. M.; Maceira, M.; Zhang, H.; ...

2015-02-18

Joint inversions of seismic data recover models that simultaneously fit multiple constraints while playing upon the strengths of each data type. Here, we jointly invert 14 years of local earthquake body wave arrival times from the Alaska Volcano Observatory catalog and Rayleigh wave dispersion curves based upon ambient noise measurements for local V p, V s, and hypocentral locations at Akutan and Makushin Volcanoes using a new joint inversion algorithm.The velocity structure and relocated seismicity of both volcanoes are significantly more complex than many other volcanoes studied using similar techniques. Seismicity is distributed among several areas beneath or beyond themore » flanks of both volcanoes, illuminating a variety of volcanic and tectonic features. The velocity structures of the two volcanoes are exemplified by the presence of narrow high-V p features in the near surface, indicating likely current or remnant pathways of magma to the surface. A single broad low-V p region beneath each volcano is slightly offset from each summit and centered at approximately 7 km depth, indicating a potential magma chamber, where magma is stored over longer time periods. Differing recovery capabilities of the Vp and Vs datasets indicate that the results of these types of joint inversions must be interpreted carefully.« less

Comparison of hand laid-up tape and filament wound composite cylinders and panels with and without impact damage

NASA Technical Reports Server (NTRS)

Jegley, Dawn C.; Lopez, Osvaldo F.

1991-01-01

Experimentally determined axial compressive failure loads, strains and failure modes of composite flat panels and cylinders are presented. A comparison of two types of filament wound flat graphite-epoxy panels indicates that the winding pattern can influence structural response. A comparison of hand laid-up tape and filament wound composite cylinders indicates that fabrication method may not significantly influence the failure mode or average failure strain of thick-walled (radius-to-thickness ratio less than 15) graphite-epoxy cylinders. The interaction of manufacturing-induced features (fiber cross-overs) and low-speed impact damage for graphite-epoxy specimens is also presented. Filament would flat panels with many fiber cross-overs exhibited lower failure strains than filament wound panels without fiber cross-overs for all impact speeds examined. Graphite-thermoplastic cylinders exhibited a significantly different failure mode from the graphite-epoxy cylinders.

Effect of age and gender on the surface electromyogram during various levels of isometric contraction.

PubMed

Arjunan, Sridhar; Kumar, Dinesh; Kalra, Chandan; Burne, John; Bastos, Teodiano

2011-01-01

This study reports the effects of age and gender on the surface electromyogram while performing isometric contraction. Experiments were conducted with two age groups--Young (Age: 20-29) and Old (Age: 60-69) where they performed sustained isometric contractions at various force levels (50%, 75%, 100% of maximum voluntary contraction). Traditional features such as root mean square (RMS) and median frequency (MDF) were computed from the recorded sEMG. The result indicates that the MDF of sEMG was not significantly affected by age, but was impacted by gender in both age groups. Also there was a significant change in the RMS of sEMG with age and gender at all levels of contraction. The results also indicate a large inter-subject variation. This study will provide an understanding of the underlying physiological effects of muscle contraction and muscle fatigue in different cohorts.

Influence of habitat heterogeneity on distribution, occupancy patterns, and productivity of breeding peregrine falcons in central West Greenland

USGS Publications Warehouse

Wightman, C.S.; Fuller, M.R.

2006-01-01

We used occupancy and productivity data collected at 67 cliffs used for nesting from 1972 to 1999 to assess patterns of distribution and nest-site selection in an increasing population of Peregrine Falcons (Falco peregrinus) in central West Greenland. Peregrine Falcons breeding at traditionally occupied cliffs used for nesting had significantly lower variation in productivity and thus these cliffs were better quality sites. This indicates that Peregrine Falcons occupied cliffs according to a pattern of despotic distribution. Falcons breeding at cliffs that were consistently occupied during the breeding season had higher average productivity and lower variation in productivity than falcons at inconsistently occupied cliffs, and thus consistent occupancy also was indicative of cliff quality. Features of high quality habitat included tall cliffs, greater change in elevation from the lowest point within 3 km of the cliff to the cliff top (elevation gain), and protection from weather on the eyrie ledge. Spacing of suitable and occupied cliffs also was an important feature, and the best cliffs generally were more isolated. Increased spacing was likely a mechanism for reducing intraspecific competition. Our results suggest that Peregrine Falcons use a resource defense strategy to compete for better quality habitats and may use spacing and physical features of a nest site to identify good quality breeding habitat. ?? The Cooper Ornithological Society 2006.

Mapping the information landscape: Discerning peaks and valleys for ecological monitoring

USGS Publications Warehouse

Moniz, L.J.; Nichols, J.D.; Nichols, J.M.

2007-01-01

We investigate previously unreported phenomena that have a potentially significant impact on the design of surveillance monitoring programs for ecological systems. Ecological monitoring practitioners have long recognized that different species are differentially informative of a system?s dynamics, as codified in the well-known concepts of indicator or keystone species. Using a novel combination of analysis techniques from nonlinear dynamics, we describe marked variation among spatial sites in information content with respect to system dynamics in the entire region. We first observed these phenomena in a spatially extended predator?prey model, but we observed strikingly similar features in verified water-level data from a NOAA/NOS Great Lakes monitoring program. We suggest that these features may be widespread and the design of surveillance monitoring programs should reflect knowledge of their existence.

Child-mother and child-father attachment security: links to internalizing adjustment among children with learning disabilities.

PubMed

Al-Yagon, Michal

2014-02-01

The study examined the unique role of children's attachment with the father and with the mother, in explaining differences in internalizing features (i.e., loneliness, sense of coherence, hope and effort, and internalizing behavior syndrome) among 107 children with learning disabilities (LD) versus 98 children with typical development ages 8-12. Preliminary analyses yielded significant group differences on most measures. SEM analysis indicated high fit between the theoretical model and empirical findings, and different patterns of relations among the model's components for the two populations. As hypothesized, child-father and child-mother attachment contributed differently to children's internalizing features for the two subgroups. Discussion focused on understanding unique and complementary roles of attachment relations with fathers versus mothers among children with and without LD.

Predicting mutational change in the speaking voice of boys.

PubMed

Fuchs, Michael; Fröehlich, Matthias; Hentschel, Bettina; Stuermer, Ingo W; Kruse, Eberhard; Knauft, Daniel

2007-03-01

The authors investigated whether acoustic speaking voice analyses can be used to predict the beginning of mutation in 21 male members of a professional boys' choir. Over a period of 3 years before mutation, children were examined every 3 months by ear, nose, and throat (ENT) and phoniatric specialists. At the same time, the voice was evaluated acoustically using analysis features of the Goettingen Hoarseness Diagram (GHD). Irregularity component and noise component, jitter, shimmer, mean waveform correlation coefficient, and fundamental frequency were determined from recordings of the speaking voice. Significant changes of acoustic features appeared 7 and 5 months before mutation onset, which indicates that vocal function is already restricted 6 months before mutation onset. This acoustic voice analysis is therefore suitable to support the care of the professional singing voice.

Child maltreatment, personality pathology, and stalking victimization among male and female college students.

PubMed

Ménard, Kim S; Pincus, Aaron L

2014-01-01

Self-report college student surveys on childhood maltreatment, and borderline and narcissistic personality features are examined to determine their influence on stalking victimization vulnerability. Stalking victimization was measured using Spitzberg and Cupach's (2008) Obsessive Relational Intrusion scale. Ordinary least squares (OLS) regression models were run separately for men (N = 677) and women (N = 1,017). Results indicated childhood sexual maltreatment and borderline traits were associated with stalking victimization among both men and women. These were the only significant relationships for men (R2 = .10). For women, stalking victimization was also associated with narcissistic grandiosity and vulnerability and with a child sexual abuse by borderline features interaction (R2 = .13), demonstrating women reporting prior sexual abuse and borderline personality pathology are especially vulnerable. Methodological and policy implications are discussed.

Discrimination of rectal cancer through human serum using surface-enhanced Raman spectroscopy

NASA Astrophysics Data System (ADS)

Li, Xiaozhou; Yang, Tianyue; Li, Siqi; Zhang, Su; Jin, Lili

2015-05-01

In this paper, surface-enhanced Raman spectroscopy (SERS) was used to detect the changes in blood serum components that accompany rectal cancer. The differences in serum SERS data between rectal cancer patients and healthy controls were examined. Postoperative rectal cancer patients also participated in the comparison to monitor the effects of cancer treatments. The results show that there are significant variations at certain wavenumbers which indicates alteration of corresponding biological substances. Principal component analysis (PCA) and parameters of intensity ratios were used on the original SERS spectra for the extraction of featured variables. These featured variables then underwent linear discriminant analysis (LDA) and classification and regression tree (CART) for the discrimination analysis. Accuracies of 93.5 and 92.4 % were obtained for PCA-LDA and parameter-CART, respectively.

Bearing monitoring

NASA Astrophysics Data System (ADS)

Xu, Roger; Stevenson, Mark W.; Kwan, Chi-Man; Haynes, Leonard S.

2001-07-01

At Ford Motor Company, thrust bearing in drill motors is often damaged by metal chips. Since the vibration frequency is several Hz only, it is very difficult to use accelerometers to pick up the vibration signals. Under the support of Ford and NASA, we propose to use a piezo film as a sensor to pick up the slow vibrations of the bearing. Then a neural net based fault detection algorithm is applied to differentiate normal bearing from bad bearing. The first step involves a Fast Fourier Transform which essentially extracts the significant frequency components in the sensor. Then Principal Component Analysis is used to further reduce the dimension of the frequency components by extracting the principal features inside the frequency components. The features can then be used to indicate the status of bearing. Experimental results are very encouraging.

Coronal Holes and Solar f -Mode Wave Scattering Off Linear Boundaries

NASA Astrophysics Data System (ADS)

Hess Webber, Shea A.

2016-11-01

Coronal holes (CHs) are solar atmospheric features that have reduced emission in the extreme ultraviolet (EUV) spectrum due to decreased plasma density along open magnetic field lines. CHs are the source of the fast solar wind, can influence other solar activity, and track the solar cycle. Our interest in them deals with boundary detection near the solar surface. Detecting CH boundaries is important for estimating their size and tracking their evolution through time, as well as for comparing the physical properties within and outside of the feature. In this thesis, we (1) investigate CHs using statistical properties and image processing techniques on EUV images to detect CH boundaries in the low corona and chromosphere. SOHO/EIT data is used to locate polar CH boundaries on the solar limb, which are then tracked through two solar cycles. Additionally, we develop an edge-detection algorithm that we use on SDO/AIA data of a polar hole extension with an approximately linear boundary. These locations are used later to inform part of the helioseismic investigation; (2) develop a local time-distance (TD) helioseismology technique that can be used to detect CH boundary signatures at the photospheric level. We employ a new averaging scheme that makes use of the quasi-linear topology of elongated scattering regions, and create simulated data to test the new technique and compare results of some associated assumptions. This method enhances the wave propagation signal in the direction perpendicular to the linear feature and reduces the computational time of the TD analysis. We also apply a new statistical analysis of the significance of differences between the TD results; and (3) apply the TD techniques to solar CH data from SDO/HMI. The data correspond to the AIA data used in the edge-detection algorithm on EUV images. We look for statistically significant differences between the TD results inside and outside the CH region. In investigation (1), we found that the polar CH areas did not change significantly between minima, even though the magnetic field strength weakened. The results of (2) indicate that TD helioseismology techniques can be extended to make use of feature symmetry in the domain. The linear technique used here produces results that differ between a linear scattering region and a circular scattering region, shown using the simulated data algorithm. This suggests that using usual TD methods on scattering regions that are radially asymmetric may produce results with signatures of the anisotropy. The results of (1) and (3) indicate that the TD signal within our CH is statistically significantly different compared to unrelated quiet sun results. Surprisingly, the TD results in the quiet sun near the CH boundary also show significant differences compared to the separate quiet sun.

Academic writing in a corpus of 4th grade science notebooks: An analysis of student language use and adult expectations of the genres of school science

NASA Astrophysics Data System (ADS)

Esquinca, Alberto

This is a study of language use in the context of an inquiry-based science curriculum in which conceptual understanding ratings are used split texts into groups of "successful" and "unsuccessful" texts. "Successful" texts could include known features of science language. 420 texts generated by students in 14 classrooms from three school districts, culled from a prior study on the effectiveness of science notebooks to assess understanding, in addition to the aforementioned ratings are the data sources. In science notebooks, students write in the process of learning (here, a unit on electricity). The analytical framework is systemic functional linguistics (Halliday and Matthiessen, 2004; Eggins, 2004), specifically the concepts of genre, register and nominalization. Genre classification involves an analysis of the purpose and register features in the text (Schleppegrell, 2004). The use of features of the scientific academic register, namely the use relational processes and nominalization (Halliday and Martin, 1993), requires transitivity analysis and noun analysis. Transitivity analysis, consisting of the identification of the process type, is conducted on 4737 ranking clauses. A manual count of each noun used in the corpus allows for a typology of nouns. Four school science genres, procedures, procedural recounts reports and explanations, are found. Most texts (85.4%) are factual, and 14.1% are classified as explanations, the analytical genre. Logistic regression analysis indicates that there is no significant probability that the texts classified as explanation are placed in the group of "successful" texts. In addition, material process clauses predominate in the corpus, followed by relational process clauses. Results of a logistic regression analysis indicate that there is a significant probability (Chi square = 15.23, p < .0001) that texts with a high rate of relational processes are placed in the group of "successful" texts. In addition, 59.5% of 6511 nouns are references to physical materials, followed by references to abstract concepts (35.54%). Only two of the concept nouns were found to be nominalized referents in definition model sentences. In sum, the corpus has recognizable genres and features science language, and relational processes are more prevalent in "successful" texts. However, the pervasive feature of science language, nominalization, is scarce.

An interdisciplinary analysis of multispectral satellite data for selected cover types in the Colorado mountains, using automatic data processing techniques

NASA Technical Reports Server (NTRS)

Hoffer, R. M. (Principal Investigator)

1974-01-01

The author has identified the following significant results. In the San Juan Mountains there exists a group of structural and topographic features which suggest a common origin. The relative positions of the San Juan Depression with the Silverton and Lake City Calderas indicate they are possibly on the edge of a large circular feature. Comparison with the 1:250,000 scale Durango Geologic Map reveals a series of radial and arcuate faults concentric with the major circular feature. Such a fracture pattern implies that the circular feature may represent the extent of a major domal uplift in the area. The uplift was very likely due to the sub-crustal emplacement of the parent magma of the San Juan volcanics and intrusives. The broad doming led to the formation of a zone of tensional ring fractures which acted as conduits of release for the magma and the eventual development of the various calderas. The ring fracturing was probably incomplete with hinging occurring in the southern and southwestern portions of the dome accounting for the lack of development of caldera structures in that portion of the area.

LMD Based Features for the Automatic Seizure Detection of EEG Signals Using SVM.

PubMed

Zhang, Tao; Chen, Wanzhong

2017-08-01

Achieving the goal of detecting seizure activity automatically using electroencephalogram (EEG) signals is of great importance and significance for the treatment of epileptic seizures. To realize this aim, a newly-developed time-frequency analytical algorithm, namely local mean decomposition (LMD), is employed in the presented study. LMD is able to decompose an arbitrary signal into a series of product functions (PFs). Primarily, the raw EEG signal is decomposed into several PFs, and then the temporal statistical and non-linear features of the first five PFs are calculated. The features of each PF are fed into five classifiers, including back propagation neural network (BPNN), K-nearest neighbor (KNN), linear discriminant analysis (LDA), un-optimized support vector machine (SVM) and SVM optimized by genetic algorithm (GA-SVM), for five classification cases, respectively. Confluent features of all PFs and raw EEG are further passed into the high-performance GA-SVM for the same classification tasks. Experimental results on the international public Bonn epilepsy EEG dataset show that the average classification accuracy of the presented approach are equal to or higher than 98.10% in all the five cases, and this indicates the effectiveness of the proposed approach for automated seizure detection.

Radiological features for the approach in trans-sphenoidal pituitary surgery.

PubMed

Twigg, Victoria; Carr, Simon D; Balakumar, Ramkishan; Sinha, Saurabh; Mirza, Showkat

2017-08-01

In order to perform trans-sphenoidal endoscopic pituitary surgery safely and efficiently it is important to identify anatomical and pituitary disease features on the pre-operative CT and MRI scans; thereby minimising the risk to surrounding structures and optimising outcomes. We aim to create a checklist to streamline pre-operative planning. We retrospectively reviewed pre-operative CT and MRI scans of 100 adults undergoing trans-sphenoidal endoscopic pituitary surgery. Radiological findings and their incidence included deviated nasal septum (62%), concha bullosa (32%), bony dehiscence of the carotid arteries (18%), sphenoid septation overlying the internal carotid artery (24% at the sella) and low lying CSF (32%). The mean distance of the sphenoid ostium to the skull base was 10 mm (range 2.7-17.6 mm). We also describe the 'teddy bear' sign which when present on an axial CT indicates the carotid arteries will be identifiable intra-operatively. There are significant variations in the anatomical and pituitary disease features between patients. We describe a number of features on pre-operative scans and have devised a checklist including a new 'teddy bear' sign to aid the surgeon in the anatomical assessment of patients undergoing trans-sphenoidal pituitary surgery.

Clinical utility of histological features of polyomavirus allograft nephropathy.

PubMed

Gaber, Lillian W; Egidi, M Francesca; Stratta, Robert J; Lo, Agnes; Moore, Linda W; Gaber, A Osama

2006-07-27

The purpose of this study was to determine if histological features of polyomavirus allograft nephropathy (PVAN) are associated with the clinical presentation and outcomes of PVAN. We examined the histological features of initial and follow-up biopsies of 20 kidney and kidney-pancreas transplant recipients with PVAN during a time prior to routine surveillance. The subjects' demographics, clinical characteristics, and outcomes were compared based upon classification of histological features of PVAN on initial biopsy. Diabetes mellitus (45%) and a history of tacrolimus-induced nephrotoxicity (35%) appeared to be prevalent in subjects with PVAN. Although histological severity of PVAN did not predict or correlate with the clinical course of PVAN, subjects with pattern C on initial PVAN biopsy presented later posttransplant, had higher serum creatinine level at presentation, and had significant allograft deterioration at follow-up than subjects with either pattern A or B on initial biopsy. Resolution of PVAN was noted in 60% of follow-up biopsies and occurred more frequently in subjects with pattern B on initial biopsy. Most subjects developed chronic allograft nephropathy after PVAN and viral clearance did not abrogate the progression to chronic allograft nephropathy. These data indicate that histologic patterns of PVAN may have clinical correlation to disease presentation and prognosis.

An iterated Laplacian based semi-supervised dimensionality reduction for classification of breast cancer on ultrasound images.

PubMed

Liu, Xiao; Shi, Jun; Zhou, Shichong; Lu, Minhua

2014-01-01

The dimensionality reduction is an important step in ultrasound image based computer-aided diagnosis (CAD) for breast cancer. A newly proposed l2,1 regularized correntropy algorithm for robust feature selection (CRFS) has achieved good performance for noise corrupted data. Therefore, it has the potential to reduce the dimensions of ultrasound image features. However, in clinical practice, the collection of labeled instances is usually expensive and time costing, while it is relatively easy to acquire the unlabeled or undetermined instances. Therefore, the semi-supervised learning is very suitable for clinical CAD. The iterated Laplacian regularization (Iter-LR) is a new regularization method, which has been proved to outperform the traditional graph Laplacian regularization in semi-supervised classification and ranking. In this study, to augment the classification accuracy of the breast ultrasound CAD based on texture feature, we propose an Iter-LR-based semi-supervised CRFS (Iter-LR-CRFS) algorithm, and then apply it to reduce the feature dimensions of ultrasound images for breast CAD. We compared the Iter-LR-CRFS with LR-CRFS, original supervised CRFS, and principal component analysis. The experimental results indicate that the proposed Iter-LR-CRFS significantly outperforms all other algorithms.

Biometric sample extraction using Mahalanobis distance in Cardioid based graph using electrocardiogram signals.

PubMed

Sidek, Khairul; Khali, Ibrahim

2012-01-01

In this paper, a person identification mechanism implemented with Cardioid based graph using electrocardiogram (ECG) is presented. Cardioid based graph has given a reasonably good classification accuracy in terms of differentiating between individuals. However, the current feature extraction method using Euclidean distance could be further improved by using Mahalanobis distance measurement producing extracted coefficients which takes into account the correlations of the data set. Identification is then done by applying these extracted features to Radial Basis Function Network. A total of 30 ECG data from MITBIH Normal Sinus Rhythm database (NSRDB) and MITBIH Arrhythmia database (MITDB) were used for development and evaluation purposes. Our experimentation results suggest that the proposed feature extraction method has significantly increased the classification performance of subjects in both databases with accuracy from 97.50% to 99.80% in NSRDB and 96.50% to 99.40% in MITDB. High sensitivity, specificity and positive predictive value of 99.17%, 99.91% and 99.23% for NSRDB and 99.30%, 99.90% and 99.40% for MITDB also validates the proposed method. This result also indicates that the right feature extraction technique plays a vital role in determining the persistency of the classification accuracy for Cardioid based person identification mechanism.

Novel Features for Brain-Computer Interfaces

PubMed Central

Woon, W. L.; Cichocki, A.

2007-01-01

While conventional approaches of BCI feature extraction are based on the power spectrum, we have tried using nonlinear features for classifying BCI data. In this paper, we report our test results and findings, which indicate that the proposed method is a potentially useful addition to current feature extraction techniques. PMID:18364991

Variations in algorithm implementation among quantitative texture analysis software packages

NASA Astrophysics Data System (ADS)

Foy, Joseph J.; Mitta, Prerana; Nowosatka, Lauren R.; Mendel, Kayla R.; Li, Hui; Giger, Maryellen L.; Al-Hallaq, Hania; Armato, Samuel G.

2018-02-01

Open-source texture analysis software allows for the advancement of radiomics research. Variations in texture features, however, result from discrepancies in algorithm implementation. Anatomically matched regions of interest (ROIs) that captured normal breast parenchyma were placed in the magnetic resonance images (MRI) of 20 patients at two time points. Six first-order features and six gray-level co-occurrence matrix (GLCM) features were calculated for each ROI using four texture analysis packages. Features were extracted using package-specific default GLCM parameters and using GLCM parameters modified to yield the greatest consistency among packages. Relative change in the value of each feature between time points was calculated for each ROI. Distributions of relative feature value differences were compared across packages. Absolute agreement among feature values was quantified by the intra-class correlation coefficient. Among first-order features, significant differences were found for max, range, and mean, and only kurtosis showed poor agreement. All six second-order features showed significant differences using package-specific default GLCM parameters, and five second-order features showed poor agreement; with modified GLCM parameters, no significant differences among second-order features were found, and all second-order features showed poor agreement. While relative texture change discrepancies existed across packages, these differences were not significant when consistent parameters were used.

Evaluation of High Density Surface Observations in Complex Terrain and Their Contribution to the MM5 Model

DTIC Science & Technology

2007-03-01

westerly surface winds, the existence of a dry-adiabatic lapse rate, and often the appearance of wave cloud features (Oard, 1993). For a long time...indicate that a large-scale mountain wave feature was present across almost the entire western United States. The GFS indicates this was a standing 31... wave and not a propagating feature since it persisted with very little movement from about 0600 UTC 6 Mar until about 0000 UTC 7 Mar. A cross

Speech recognition features for EEG signal description in detection of neonatal seizures.

PubMed

Temko, A; Boylan, G; Marnane, W; Lightbody, G

2010-01-01

In this work, features which are usually employed in automatic speech recognition (ASR) are used for the detection of neonatal seizures in newborn EEG. Three conventional ASR feature sets are compared to the feature set which has been previously developed for this task. The results indicate that the thoroughly-studied spectral envelope based ASR features perform reasonably well on their own. Additionally, the SVM Recursive Feature Elimination routine is applied to all extracted features pooled together. It is shown that ASR features consistently appear among the top-rank features.

An Automated and Intelligent Medical Decision Support System for Brain MRI Scans Classification.

PubMed

Siddiqui, Muhammad Faisal; Reza, Ahmed Wasif; Kanesan, Jeevan

2015-01-01

A wide interest has been observed in the medical health care applications that interpret neuroimaging scans by machine learning systems. This research proposes an intelligent, automatic, accurate, and robust classification technique to classify the human brain magnetic resonance image (MRI) as normal or abnormal, to cater down the human error during identifying the diseases in brain MRIs. In this study, fast discrete wavelet transform (DWT), principal component analysis (PCA), and least squares support vector machine (LS-SVM) are used as basic components. Firstly, fast DWT is employed to extract the salient features of brain MRI, followed by PCA, which reduces the dimensions of the features. These reduced feature vectors also shrink the memory storage consumption by 99.5%. At last, an advanced classification technique based on LS-SVM is applied to brain MR image classification using reduced features. For improving the efficiency, LS-SVM is used with non-linear radial basis function (RBF) kernel. The proposed algorithm intelligently determines the optimized values of the hyper-parameters of the RBF kernel and also applied k-fold stratified cross validation to enhance the generalization of the system. The method was tested by 340 patients' benchmark datasets of T1-weighted and T2-weighted scans. From the analysis of experimental results and performance comparisons, it is observed that the proposed medical decision support system outperformed all other modern classifiers and achieves 100% accuracy rate (specificity/sensitivity 100%/100%). Furthermore, in terms of computation time, the proposed technique is significantly faster than the recent well-known methods, and it improves the efficiency by 71%, 3%, and 4% on feature extraction stage, feature reduction stage, and classification stage, respectively. These results indicate that the proposed well-trained machine learning system has the potential to make accurate predictions about brain abnormalities from the individual subjects, therefore, it can be used as a significant tool in clinical practice.

Large Erosional Features on the Cascadia Accretionary Wedge Imaged with New High-Resolution Multibeam Bathymetry and Seismic Datasets

NASA Astrophysics Data System (ADS)

Beeson, J. W.; Goldfinger, C.

2013-12-01

Utilizing new high resolution multibeam bathymetric data along with chirp sub-bottom and multichannel seismic reflection (MCS) data, we identified remarkable erosional features on the toe of the Cascadia accretionary wedge near Willapa Canyon, offshore Washington, USA. Bathymetric data was compiled from the Cascadia Open-Access Seismic Transects (COAST) cruise and from the site survey cruise for the Cascadia Initiative. These features loosely resemble slope failures of the frontal thrust, but can be distinguished from such failures by several key features: They incise the crest of the frontal thrust and encompass the landward limb; They have floors below the level of the abyssal plain, similar to plunge pool morphology; They show no evidence of landslide blocks at the base of the slope indicative of block sliding. The features where likely formed during the latest Pleistocene based on post event deposition, cross-cutting relationships with Juan de Fuca Channel and the Willapa Channel levees and wave field, and post event slip on the frontal thrust of the Cascadia accretionary prism. The Holocene levees of both Willapa Channel and Juan de Fuca Channel overlap these older features, and clearly place an upper bound on the age of the erosional features in the latest Pleistocene. A lower bound is estimated from a sub-bottom profile that images ~30 meters of post scour sediment fill. Using existing literature of Holocene and Pleistocene sedimentation rates we estimate a lower age bound between ~23,000 - 56,000 y.b.p. We also map a fault scarp within the erosional feature, with ~60 m of vertical offset. Using multi-channel seismic reflection profiles from the COAST cruise we interpret this scarp as the surface expression of the landward vergent frontal thrust fault. The apparent short duration of the erosional event along the seaward margin of the accretionary wedge, coupled with the presence of the fresh fault scarp within the erosion zone, are indicative of a dormant feature with significant time required to develop the scarp after cessation of the causative process. Based on morphology, dissimilarity with other submarine features, and available age constraints, we infer that these features were most likely formed during the glacial lake outpouring in the Pacific Northwest known as the Missoula floods which occurred 13,000-19,500 y.b.p. The features themselves bear a strong resemblance to 'coulees' formed during the same glacial events onshore, and the outpourings through Willapa Channel are consistent with previous inferences of the deposition of Missoula Flood deposits in Escanaba Trough. If this timing is correct, the slip rate along the Cascadia frontal thrust can be estimated using fault geometry and scarp height as 2.8 - 4.1 mm/yr.

Distinct contributions of functional and deep neural network features to representational similarity of scenes in human brain and behavior

PubMed Central

Greene, Michelle R; Baldassano, Christopher; Fei-Fei, Li; Beck, Diane M; Baker, Chris I

2018-01-01

Inherent correlations between visual and semantic features in real-world scenes make it difficult to determine how different scene properties contribute to neural representations. Here, we assessed the contributions of multiple properties to scene representation by partitioning the variance explained in human behavioral and brain measurements by three feature models whose inter-correlations were minimized a priori through stimulus preselection. Behavioral assessments of scene similarity reflected unique contributions from a functional feature model indicating potential actions in scenes as well as high-level visual features from a deep neural network (DNN). In contrast, similarity of cortical responses in scene-selective areas was uniquely explained by mid- and high-level DNN features only, while an object label model did not contribute uniquely to either domain. The striking dissociation between functional and DNN features in their contribution to behavioral and brain representations of scenes indicates that scene-selective cortex represents only a subset of behaviorally relevant scene information. PMID:29513219

Distinct contributions of functional and deep neural network features to representational similarity of scenes in human brain and behavior.

PubMed

Groen, Iris Ia; Greene, Michelle R; Baldassano, Christopher; Fei-Fei, Li; Beck, Diane M; Baker, Chris I

2018-03-07

Inherent correlations between visual and semantic features in real-world scenes make it difficult to determine how different scene properties contribute to neural representations. Here, we assessed the contributions of multiple properties to scene representation by partitioning the variance explained in human behavioral and brain measurements by three feature models whose inter-correlations were minimized a priori through stimulus preselection. Behavioral assessments of scene similarity reflected unique contributions from a functional feature model indicating potential actions in scenes as well as high-level visual features from a deep neural network (DNN). In contrast, similarity of cortical responses in scene-selective areas was uniquely explained by mid- and high-level DNN features only, while an object label model did not contribute uniquely to either domain. The striking dissociation between functional and DNN features in their contribution to behavioral and brain representations of scenes indicates that scene-selective cortex represents only a subset of behaviorally relevant scene information.

Automatically measuring the effect of strategy drawing features on pupils' handwriting and gender

NASA Astrophysics Data System (ADS)

Tabatabaey-Mashadi, Narges; Sudirman, Rubita; Guest, Richard M.; Khalid, Puspa Inayat

2013-12-01

Children's dynamic drawing strategies have been recently recognized as indicators of handwriting ability. However the influence of each feature in predicting handwriting is unknown due to lack of a measuring system. An automated measuring algorithm suitable for psychological assessment and non-subjective scoring is presented here. Using the weight vector and classification rate of a machine learning algorithm, an overall feature's effect is calculated which is comparable in different groupings. In this study thirteen previously detected drawing strategy features are measured for their influence on handwriting and gender. Features are extracted from drawing a triangle, Beery VMI and Bender Gestalt tangent patterns. Samples are related to 203 pupils (77 below average writers, and 101 female). The results show that the number of strokes in drawing the triangle pattern plays a major role in both groupings; however Left Tendency flag feature is affected by children's handwriting about 2.5 times greater than their gender. Experiments indicate that different forms of a feature sometimes show different influences.

Green Infrastructure Increases Biogeochemical Responsiveness, Vegetation Growth and Decreases Runoff in a Semi-Arid City, Tucson, AZ, USA

NASA Astrophysics Data System (ADS)

Meixner, T.; Papuga, S. A.; Luketich, A. M.; Rockhill, T.; Gallo, E. L.; Anderson, J.; Salgado, L.; Pope, K.; Gupta, N.; Korgaonkar, Y.; Guertin, D. P.

2017-12-01

Green Infrastructure (GI) is often viewed as a mechanism to minimize the effects of urbanization on hydrology, water quality, and other ecosystem services (including the urban heat island). Quantifying the effects of GI requires field measurements of the dimensions of biogeochemical, ecosystem, and hydrologic function that we expect GI to impact. Here we investigated the effect of GI features in Tucson, Arizona which has a low intensity winter precipitation regime and a high intensity summer regime. We focused on understanding the effect of GI on soil hydraulic and biogeochemical properties as well as the effect on vegetation and canopy temperature. Our results demonstrate profound changes in biogeochemical and hydrologic properties and vegetation growth between GI systems and nearby control sites. In terms of hydrologic properties GI soils had increased water holding capacity and hydraulic conductivity. GI soils also have higher total carbon, total nitrogen, and organic matter in general than control soils. Furthermore, we tested the sampled soils (control and GI) for differences in biogeochemical response upon wetting. GI soils had larger respiration responses indicating greater biogeochemical activity overall. Long-term Lidar surveys were used to investigate the differential canopy growth of GI systems versus control sites. The results of this analysis indicate that while a significant amount of time is needed to observe differences in canopy growth GI features due increase tree size and thus likely impact street scale ambient temperatures. Additionally monitoring of transpiration, soil moisture, and canopy temperature demonstrates that GI features increase vegetation growth and transpiration and reduce canopy temperatures. These biogeochemical and ecohydrologic results indicate that GI can increase the biogeochemical processing of soils and increase tree growth and thus reduce urban ambient temperatures.

Multidetector CT features of pulmonary focal ground-glass opacity: differences between benign and malignant

PubMed Central

Fan, L; Liu, S-Y; Li, Q-C; Yu, H; Xiao, X-S

2012-01-01

Objective To evaluate different features between benign and malignant pulmonary focal ground-glass opacity (fGGO) on multidetector CT (MDCT). Methods 82 pathologically or clinically confirmed fGGOs were retrospectively analysed with regard to demographic data, lesion size and location, attenuation value and MDCT features including shape, margin, interface, internal characteristics and adjacent structure. Differences between benign and malignant fGGOs were analysed using a χ2 test, Fisher's exact test or Mann–Whitney U-test. Morphological characteristics were analysed by binary logistic regression analysis to estimate the likelihood of malignancy. Results There were 21 benign and 61 malignant lesions. No statistical differences were found between benign and malignant fGGOs in terms of demographic data, size, location and attenuation value. The frequency of lobulation (p=0.000), spiculation (p=0.008), spine-like process (p=0.004), well-defined but coarse interface (p=0.000), bronchus cut-off (p=0.003), other air-containing space (p=0.000), pleural indentation (p=0.000) and vascular convergence (p=0.006) was significantly higher in malignant fGGOs than that in benign fGGOs. Binary logistic regression analysis showed that lobulation, interface and pleural indentation were important indicators for malignant diagnosis of fGGO, with the corresponding odds ratios of 8.122, 3.139 and 9.076, respectively. In addition, a well-defined but coarse interface was the most important indicator of malignancy among all interface types. With all three important indicators considered, the diagnostic sensitivity, specificity and accuracy were 93.4%, 66.7% and 86.6%, respectively. Conclusion An fGGO with lobulation, a well-defined but coarse interface and pleural indentation gives a greater than average likelihood of being malignant. PMID:22128130

Structural features based genome-wide characterization and prediction of nucleosome organization

PubMed Central

2012-01-01

Background Nucleosome distribution along chromatin dictates genomic DNA accessibility and thus profoundly influences gene expression. However, the underlying mechanism of nucleosome formation remains elusive. Here, taking a structural perspective, we systematically explored nucleosome formation potential of genomic sequences and the effect on chromatin organization and gene expression in S. cerevisiae. Results We analyzed twelve structural features related to flexibility, curvature and energy of DNA sequences. The results showed that some structural features such as DNA denaturation, DNA-bending stiffness, Stacking energy, Z-DNA, Propeller twist and free energy, were highly correlated with in vitro and in vivo nucleosome occupancy. Specifically, they can be classified into two classes, one positively and the other negatively correlated with nucleosome occupancy. These two kinds of structural features facilitated nucleosome binding in centromere regions and repressed nucleosome formation in the promoter regions of protein-coding genes to mediate transcriptional regulation. Based on these analyses, we integrated all twelve structural features in a model to predict more accurately nucleosome occupancy in vivo than the existing methods that mainly depend on sequence compositional features. Furthermore, we developed a novel approach, named DLaNe, that located nucleosomes by detecting peaks of structural profiles, and built a meta predictor to integrate information from different structural features. As a comparison, we also constructed a hidden Markov model (HMM) to locate nucleosomes based on the profiles of these structural features. The result showed that the meta DLaNe and HMM-based method performed better than the existing methods, demonstrating the power of these structural features in predicting nucleosome positions. Conclusions Our analysis revealed that DNA structures significantly contribute to nucleosome organization and influence chromatin structure and gene expression regulation. The results indicated that our proposed methods are effective in predicting nucleosome occupancy and positions and that these structural features are highly predictive of nucleosome organization. The implementation of our DLaNe method based on structural features is available online. PMID:22449207

Study of Advanced Propulsion Systems for Small Transport Aircraft Technology (STAT) Program

NASA Technical Reports Server (NTRS)

Baerst, C. F.; Heldenbrand, R. W.; Rowse, J. H.

1981-01-01

Definitions of takeoff gross weight, performance, and direct operating cost for both a 30 and 50 passenger airplane were established. The results indicate that a potential direct operating cost benefit, resulting from advanced technologies, of approximately 20 percent would be achieved for the 1990 engines. Of the numerous design features that were evaluated, only maintenance-related items contributed to a significant decrease in direct operating cost. Recommendations are made to continue research and technology programs for advanced component and engine development.

Ice sheet topography by satellite altimetry

USGS Publications Warehouse

Brooks, R.L.; Campbell, W.J.; Ramseier, R.O.; Stanley, H.R.; Zwally, H.J.

1978-01-01

The surface elevation of the southern Greenland ice sheet and surface features of the ice flow are obtained from the radar altimeter on the GEOS 3 satellite. The achieved accuracy in surface elevation is ???2 m. As changes in surface elevation are indicative of changes in ice volume, the mass balance of the present ice sheets could be determined by repetitive mapping of the surface elevation and the surface could be monitored to detect surging or significant changes in ice flow. ?? 1978 Nature Publishing Group.

The coupled effects of chemistry and diffusion on the stratospheric ozone reduction

NASA Technical Reports Server (NTRS)

Gupta, R. N.; Grose, W. L.

1980-01-01

The effect of diffusive-mixing on O3-depletion is estimated using the five-step chemistry model. The coupled treatment uses an equilibrium turbulence field and retains the key features of the kinetics while keeping the chemistry simple. Results indicate that those calculations of Hilst and Donaldson (1973) employing the conservation of NO2/NO will yield erroneous results, and it is found that any significant level of turbulence will reduce the severity of the NOx catalytic cycle for O3 destruction.

The value of anthropometric indices for identifying women with features of metabolic syndrome

USDA-ARS?s Scientific Manuscript database

BMI is a widely used anthropometric measure for identifying CVD and metabolic syndrome (MetS) risk. Two new anthropometric indices are A Body Shape Index (ABSI) and Body Roundness Index (BRI) that may provide better correlations to features of MetS. Methods: Subject data were obtained from 91 over...

You shall know an object by the company it keeps: An investigation of semantic representations derived from object co-occurrence in visual scenes.

PubMed

Sadeghi, Zahra; McClelland, James L; Hoffman, Paul

2015-09-01

An influential position in lexical semantics holds that semantic representations for words can be derived through analysis of patterns of lexical co-occurrence in large language corpora. Firth (1957) famously summarised this principle as "you shall know a word by the company it keeps". We explored whether the same principle could be applied to non-verbal patterns of object co-occurrence in natural scenes. We performed latent semantic analysis (LSA) on a set of photographed scenes in which all of the objects present had been manually labelled. This resulted in a representation of objects in a high-dimensional space in which similarity between two objects indicated the degree to which they appeared in similar scenes. These representations revealed similarities among objects belonging to the same taxonomic category (e.g., items of clothing) as well as cross-category associations (e.g., between fruits and kitchen utensils). We also compared representations generated from this scene dataset with two established methods for elucidating semantic representations: (a) a published database of semantic features generated verbally by participants and (b) LSA applied to a linguistic corpus in the usual fashion. Statistical comparisons of the three methods indicated significant association between the structures revealed by each method, with the scene dataset displaying greater convergence with feature-based representations than did LSA applied to linguistic data. The results indicate that information about the conceptual significance of objects can be extracted from their patterns of co-occurrence in natural environments, opening the possibility for such data to be incorporated into existing models of conceptual representation. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

Discerning mild cognitive impairment and Alzheimer Disease from normal aging: morphologic characterization based on univariate and multivariate models.

PubMed

Liao, Weiqi; Long, Xiaojing; Jiang, Chunxiang; Diao, Yanjun; Liu, Xin; Zheng, Hairong; Zhang, Lijuan

2014-05-01

Differentiating mild cognitive impairment (MCI) and Alzheimer Disease (AD) from healthy aging remains challenging. This study aimed to explore the cerebral structural alterations of subjects with MCI or AD as compared to healthy elderly based on the individual and collective effects of cerebral morphologic indices using univariate and multivariate analyses. T1-weighted images (T1WIs) were retrieved from Alzheimer Disease Neuroimaging Initiative database for 116 subjects who were categorized into groups of healthy aging, MCI, and AD. Analysis of covariance (ANCOVA) and multivariate analysis of covariance (MANCOVA) were performed to explore the intergroup morphologic alterations indexed by surface area, curvature index, cortical thickness, and subjacent white matter volume with age and sex controlled as covariates, in 34 parcellated gyri regions of interest (ROIs) for both cerebral hemispheres based on the T1WI. Statistical parameters were mapped on the anatomic images to facilitate visual inspection. Global rather than region-specific structural alterations were revealed in groups of MCI and AD relative to healthy elderly using MANCOVA. ANCOVA revealed that the cortical thickness decreased more prominently in entorhinal, temporal, and cingulate cortices and was positively correlated with patients' cognitive performance in AD group but not in MCI. The temporal lobe features marked atrophy of white matter during the disease dynamics. Significant intercorrelations were observed among the morphologic indices with univariate analysis for given ROIs. Significant global structural alterations were identified in MCI and AD based on MANCOVA model with improved sensitivity. The intercorrelation among the morphologic indices may dampen the use of individual morphological parameter in featuring cerebral structural alterations. Decrease in cortical thickness is not reflective of the cognitive performance at the early stage of AD. Copyright © 2014 AUR. Published by Elsevier Inc. All rights reserved.

Lithospheric rheological heterogeneity across an intraplate rift basin (Linfen Basin, North China) constrained from magnetotelluric data: Implications for seismicity and rift evolution

NASA Astrophysics Data System (ADS)

Yin, Yaotian; Jin, Sheng; Wei, Wenbo; Ye, Gaofeng; Jing, Jian'en; Zhang, Letian; Dong, Hao; Xie, Chengliang; Liang, Hongda

2017-10-01

We take the Linfen Basin, which is the most active segment of the Cenozoic intraplate Shanxi Rift, as an example, showing how to use magnetotelluric data to constrain lithospheric rheological heterogeneities of intraplate tectonic zones. Electrical resistivity models, combined with previous rheological numerical simulation, show a good correlation between resistivity and rheological strength, indicating the mechanisms of enhanced conductivity could also be reasons of reduced viscosity. The crust beneath the Linfen Basin shows overall stratified features in both electrical resistivity and rheology. The uppermost crustal conductive layer is dominated by friction sliding-type brittle fracturing. The high-resistivity mid-crust is inferred to be high-viscosity metamorphic basement being intersected by deep fault. The plastic lower crust show significantly high-conductivity feature. Seismicity appears to be controlled by crustal rheological heterogeneity. Micro-earthquakes mainly distribute at the brittle-ductile transition zones as indicated by high- to low-resistivity interfaces or the high pore pressure fault zones while the epicenters of two giant destructive historical earthquakes occur within the high-resistivity and therefore high-strength blocks near the inferred rheological interfaces. The lithosphere-scale lateral rheological heterogeneity along the profile can also be illustrated. The crust and upper mantle beneath the Ordos Block, Lüliang Mountains and Taihang Mountains are of high rheological strength as indicated by large-scale high-resistivity zones while a significant high-conductivity, lithosphere-scale weak zone exists beneath the eastern margin of the Linfen Basin. According to previous geodynamic modeling works, we suggest that this kind of lateral rheological heterogeneity may play an essential role for providing driving force for the formation and evolution of the Shanxi Rift, regional lithospheric deformation and earthquake activities under the far-field effects of the India-Eurasian Collision.

Spectral dependence of texture features integrated with hyperspectral data for area target classification improvement

NASA Astrophysics Data System (ADS)

Bangs, Corey F.; Kruse, Fred A.; Olsen, Chris R.

2013-05-01

Hyperspectral data were assessed to determine the effect of integrating spectral data and extracted texture feature data on classification accuracy. Four separate spectral ranges (hundreds of spectral bands total) were used from the Visible and Near Infrared (VNIR) and Shortwave Infrared (SWIR) portions of the electromagnetic spectrum. Haralick texture features (contrast, entropy, and correlation) were extracted from the average gray-level image for each of the four spectral ranges studied. A maximum likelihood classifier was trained using a set of ground truth regions of interest (ROIs) and applied separately to the spectral data, texture data, and a fused dataset containing both. Classification accuracy was measured by comparison of results to a separate verification set of test ROIs. Analysis indicates that the spectral range (source of the gray-level image) used to extract the texture feature data has a significant effect on the classification accuracy. This result applies to texture-only classifications as well as the classification of integrated spectral data and texture feature data sets. Overall classification improvement for the integrated data sets was near 1%. Individual improvement for integrated spectral and texture classification of the "Urban" class showed approximately 9% accuracy increase over spectral-only classification. Texture-only classification accuracy was highest for the "Dirt Path" class at approximately 92% for the spectral range from 947 to 1343nm. This research demonstrates the effectiveness of texture feature data for more accurate analysis of hyperspectral data and the importance of selecting the correct spectral range to be used for the gray-level image source to extract these features.

Inferring diagnosis and trajectory of wet age-related macular degeneration from OCT imagery of retina

NASA Astrophysics Data System (ADS)

Irvine, John M.; Ghadar, Nastaran; Duncan, Steve; Floyd, David; O'Dowd, David; Lin, Kristie; Chang, Tom

2017-03-01

Quantitative biomarkers for assessing the presence, severity, and progression of age-related macular degeneration (AMD) would benefit research, diagnosis, and treatment. This paper explores development of quantitative biomarkers derived from OCT imagery of the retina. OCT images for approximately 75 patients with Wet AMD, Dry AMD, and no AMD (healthy eyes) were analyzed to identify image features indicative of the patients' conditions. OCT image features provide a statistical characterization of the retina. Healthy eyes exhibit a layered structure, whereas chaotic patterns indicate the deterioration associated with AMD. Our approach uses wavelet and Frangi filtering, combined with statistical features that do not rely on image segmentation, to assess patient conditions. Classification analysis indicates clear separability of Wet AMD from other conditions, including Dry AMD and healthy retinas. The probability of correct classification of was 95.7%, as determined from cross validation. Similar classification analysis predicts the response of Wet AMD patients to treatment, as measured by the Best Corrected Visual Acuity (BCVA). A statistical model predicts BCVA from the imagery features with R2 = 0.846. Initial analysis of OCT imagery indicates that imagery-derived features can provide useful biomarkers for characterization and quantification of AMD: Accurate assessment of Wet AMD compared to other conditions; image-based prediction of outcome for Wet AMD treatment; and features derived from the OCT imagery accurately predict BCVA; unlike many methods in the literature, our techniques do not rely on segmentation of the OCT image. Next steps include larger scale testing and validation.

Acoustic Features Influence Musical Choices Across Multiple Genres

PubMed Central

Barone, Michael D.; Bansal, Jotthi; Woolhouse, Matthew H.

2017-01-01

Based on a large behavioral dataset of music downloads, two analyses investigate whether the acoustic features of listeners' preferred musical genres influence their choice of tracks within non-preferred, secondary musical styles. Analysis 1 identifies feature distributions for pairs of genre-defined subgroups that are distinct. Using correlation analysis, these distributions are used to test the degree of similarity between subgroups' main genres and the other music within their download collections. Analysis 2 explores the issue of main-to-secondary genre influence through the production of 10 feature-influence matrices, one per acoustic feature, in which cell values indicate the percentage change in features for genres and subgroups compared to overall population averages. In total, 10 acoustic features and 10 genre-defined subgroups are explored within the two analyses. Results strongly indicate that the acoustic features of people's main genres influence the tracks they download within non-preferred, secondary musical styles. The nature of this influence and its possible actuating mechanisms are discussed with respect to research on musical preference, personality, and statistical learning. PMID:28725200

Oropharyngeal Dysphagia in Dermatomyositis: Associations with Clinical and Laboratory Features Including Autoantibodies

PubMed Central

Mugii, Naoki; Hasegawa, Minoru; Matsushita, Takashi; Hamaguchi, Yasuhito; Oohata, Sacihe; Okita, Hirokazu; Yahata, Tetsutarou; Someya, Fujiko; Inoue, Katsumi; Murono, Shigeyuki; Fujimoto, Manabu; Takehara, Kazuhiko

2016-01-01

Objective Dysphagia develops with low frequency in patients with dermatomyositis. Our objective was to determine the clinical and laboratory features that can estimate the development of dysphagia in dermatomyositis. Methods This study included 92 Japanese patients with adult-onset dermatomyositis. The associations between dysphagia and clinical and laboratory features including disease-specific autoantibodies determined by immunoprecipitation assays were analyzed. Results Videofluoroscopy swallow study (VFSS) was performed for all patients with clinical dysphagia (n = 13, 14.1%) but not for patients without clinical dysphagia. Typical findings of dysphagia (pharyngeal pooling, n = 11 and/or nasal regurgitation, n = 4) was detected by VFSS in all patients with clinical dysphagia. Eleven patients with dysphagia (84.6%) had anti-transcription intermediary factor 1γ (TIF-1γ) antibody. By univariate analysis, the average age and the male to female ratio, internal malignancy, and anti-TIF-1γ antibody were significantly higher and the frequency of interstitial lung diseases and manual muscle testing (MMT) scores of sternomastoid and dertoid muscles were significantly lower in patients with dysphagia than in patients without dysphagia. Among patients with anti-TIF-1γ antibody, the mean age, the ratios of male to female and internal malignancy were significantly higher and mean MMT scores of sternomastoid muscle were significantly lower in patients with dysphagia compared with patients without dysphagia. By multivariable analysis, the risk of dysphagia was strongly associated with the existence of internal malignancy and ant-TIF-1γ antibody and was also associated with reduced scores of manual muscle test of sternomastoid muscle. Dysphagia was markedly improved after the treatment against myositis in all 13 patients. Conclusion These findings indicate that dysphagia can develop frequently in patients with internal malignancy, anti-TIF-1γ antibody, or severe muscle weakness of sternomastoid muscle. PMID:27167831

Oropharyngeal Dysphagia in Dermatomyositis: Associations with Clinical and Laboratory Features Including Autoantibodies.

PubMed

Mugii, Naoki; Hasegawa, Minoru; Matsushita, Takashi; Hamaguchi, Yasuhito; Oohata, Sacihe; Okita, Hirokazu; Yahata, Tetsutarou; Someya, Fujiko; Inoue, Katsumi; Murono, Shigeyuki; Fujimoto, Manabu; Takehara, Kazuhiko

2016-01-01

Dysphagia develops with low frequency in patients with dermatomyositis. Our objective was to determine the clinical and laboratory features that can estimate the development of dysphagia in dermatomyositis. This study included 92 Japanese patients with adult-onset dermatomyositis. The associations between dysphagia and clinical and laboratory features including disease-specific autoantibodies determined by immunoprecipitation assays were analyzed. Videofluoroscopy swallow study (VFSS) was performed for all patients with clinical dysphagia (n = 13, 14.1%) but not for patients without clinical dysphagia. Typical findings of dysphagia (pharyngeal pooling, n = 11 and/or nasal regurgitation, n = 4) was detected by VFSS in all patients with clinical dysphagia. Eleven patients with dysphagia (84.6%) had anti-transcription intermediary factor 1γ (TIF-1γ) antibody. By univariate analysis, the average age and the male to female ratio, internal malignancy, and anti-TIF-1γ antibody were significantly higher and the frequency of interstitial lung diseases and manual muscle testing (MMT) scores of sternomastoid and dertoid muscles were significantly lower in patients with dysphagia than in patients without dysphagia. Among patients with anti-TIF-1γ antibody, the mean age, the ratios of male to female and internal malignancy were significantly higher and mean MMT scores of sternomastoid muscle were significantly lower in patients with dysphagia compared with patients without dysphagia. By multivariable analysis, the risk of dysphagia was strongly associated with the existence of internal malignancy and ant-TIF-1γ antibody and was also associated with reduced scores of manual muscle test of sternomastoid muscle. Dysphagia was markedly improved after the treatment against myositis in all 13 patients. These findings indicate that dysphagia can develop frequently in patients with internal malignancy, anti-TIF-1γ antibody, or severe muscle weakness of sternomastoid muscle.

Solution pans and linear sand bedforms on the bare-rock limestone shelf of the Campeche Bank, Yucatán Peninsula, Mexico

NASA Astrophysics Data System (ADS)

Goff, John A.; Gulick, Sean P. S.; Cruz, Ligia Perez; Stewart, Heather A.; Davis, Marcy; Duncan, Dan; Saustrup, Steffen; Sanford, Jason; Fucugauchi, Jaime Urrutia

2016-04-01

A high-resolution, near-surface geophysical survey was conducted in 2013 on the Campeche Bank, a carbonate platform offshore of Yucatán, Mexico, to provide a hazard assessment for future scientific drilling into the Chicxulub impact crater. It also provided an opportunity to obtain detailed information on the seafloor morphology and shallow stratigraphy of this understudied region. The seafloor exhibited two morphologies: (1) small-scale (<2 m) bare-rock karstic features, and (2) thin (<1 m) linear sand accumulations overlying the bedrock. Solution pans, circular to oblong depressions featured flat bottoms and steep sides, were the dominant karstic features; they are known to form subaerially by the pooling of rainwater and dissolution of carbonate. Observed pans were 10-50 cm deep and generally 1-8 m wide, but occasionally reach 15 m, significantly larger than any solution pan observed on land (maximum 6 m). These features likely grew over the course of many 10's of thousands of years in an arid environment while subaerially exposed during lowered sea levels. Surface sands are organized into linear bedforms oriented NE-SW, 10's to 100's meters wide, and kilometers long. These features are identified as sand ribbons (longitudinal bedforms), and contained asymmetric secondary transverse bedforms that indicate NE-directed flow. This orientation is incompatible with the prevalent westward current direction; we hypothesize that these features are storm-generated.

Perceptual representation and effectiveness of local figure–ground cues in natural contours

PubMed Central

Sakai, Ko; Matsuoka, Shouhei; Kurematsu, Ken; Hatori, Yasuhiro

2015-01-01

A contour shape strongly influences the perceptual segregation of a figure from the ground. We investigated the contribution of local contour shape to figure–ground segregation. Although previous studies have reported local contour features that evoke figure–ground perception, they were often image features and not necessarily perceptual features. First, we examined whether contour features, specifically, convexity, closure, and symmetry, underlie the perceptual representation of natural contour shapes. We performed similarity tests between local contours, and examined the contribution of the contour features to the perceptual similarities between the contours. The local contours were sampled from natural contours so that their distribution was uniform in the space composed of the three contour features. This sampling ensured the equal appearance frequency of the factors and a wide variety of contour shapes including those comprised of contradictory factors that induce figure in the opposite directions. This sampling from natural contours is advantageous in order to randomly pickup a variety of contours that satisfy a wide range of cue combinations. Multidimensional scaling analyses showed that the combinations of convexity, closure, and symmetry contribute to perceptual similarity, thus they are perceptual quantities. Second, we examined whether the three features contribute to local figure–ground perception. We performed psychophysical experiments to judge the direction of the figure along the local contours, and examined the contribution of the features to the figure–ground judgment. Multiple linear regression analyses showed that closure was a significant factor, but that convexity and symmetry were not. These results indicate that closure is dominant in the local figure–ground perception with natural contours when the other cues coexist with equal probability including contradictory cases. PMID:26579057

Automatic brain MR image denoising based on texture feature-based artificial neural networks.

PubMed

Chang, Yu-Ning; Chang, Herng-Hua

2015-01-01

Noise is one of the main sources of quality deterioration not only for visual inspection but also in computerized processing in brain magnetic resonance (MR) image analysis such as tissue classification, segmentation and registration. Accordingly, noise removal in brain MR images is important for a wide variety of subsequent processing applications. However, most existing denoising algorithms require laborious tuning of parameters that are often sensitive to specific image features and textures. Automation of these parameters through artificial intelligence techniques will be highly beneficial. In the present study, an artificial neural network associated with image texture feature analysis is proposed to establish a predictable parameter model and automate the denoising procedure. In the proposed approach, a total of 83 image attributes were extracted based on four categories: 1) Basic image statistics. 2) Gray-level co-occurrence matrix (GLCM). 3) Gray-level run-length matrix (GLRLM) and 4) Tamura texture features. To obtain the ranking of discrimination in these texture features, a paired-samples t-test was applied to each individual image feature computed in every image. Subsequently, the sequential forward selection (SFS) method was used to select the best texture features according to the ranking of discrimination. The selected optimal features were further incorporated into a back propagation neural network to establish a predictable parameter model. A wide variety of MR images with various scenarios were adopted to evaluate the performance of the proposed framework. Experimental results indicated that this new automation system accurately predicted the bilateral filtering parameters and effectively removed the noise in a number of MR images. Comparing to the manually tuned filtering process, our approach not only produced better denoised results but also saved significant processing time.

Evaluation of correlation between CT image features and ERCC1 protein expression in assessing lung cancer prognosis

NASA Astrophysics Data System (ADS)

Tan, Maxine; Emaminejad, Nastaran; Qian, Wei; Sun, Shenshen; Kang, Yan; Guan, Yubao; Lure, Fleming; Zheng, Bin

2014-03-01

Stage I non-small-cell lung cancers (NSCLC) usually have favorable prognosis. However, high percentage of NSCLC patients have cancer relapse after surgery. Accurately predicting cancer prognosis is important to optimally treat and manage the patients to minimize the risk of cancer relapse. Studies have shown that an excision repair crosscomplementing 1 (ERCC1) gene was a potentially useful genetic biomarker to predict prognosis of NSCLC patients. Meanwhile, studies also found that chronic obstructive pulmonary disease (COPD) was highly associated with lung cancer prognosis. In this study, we investigated and evaluated the correlations between COPD image features and ERCC1 gene expression. A database involving 106 NSCLC patients was used. Each patient had a thoracic CT examination and ERCC1 genetic test. We applied a computer-aided detection scheme to segment and quantify COPD image features. A logistic regression method and a multilayer perceptron network were applied to analyze the correlation between the computed COPD image features and ERCC1 protein expression. A multilayer perceptron network (MPN) was also developed to test performance of using COPD-related image features to predict ERCC1 protein expression. A nine feature based logistic regression analysis showed the average COPD feature values in the low and high ERCC1 protein expression groups are significantly different (p < 0.01). Using a five-fold cross validation method, the MPN yielded an area under ROC curve (AUC = 0.669±0.053) in classifying between the low and high ERCC1 expression cases. The study indicates that CT phenotype features are associated with the genetic tests, which may provide supplementary information to help improve accuracy in assessing prognosis of NSCLC patients.

Perceptual representation and effectiveness of local figure-ground cues in natural contours.

PubMed

Sakai, Ko; Matsuoka, Shouhei; Kurematsu, Ken; Hatori, Yasuhiro

2015-01-01

A contour shape strongly influences the perceptual segregation of a figure from the ground. We investigated the contribution of local contour shape to figure-ground segregation. Although previous studies have reported local contour features that evoke figure-ground perception, they were often image features and not necessarily perceptual features. First, we examined whether contour features, specifically, convexity, closure, and symmetry, underlie the perceptual representation of natural contour shapes. We performed similarity tests between local contours, and examined the contribution of the contour features to the perceptual similarities between the contours. The local contours were sampled from natural contours so that their distribution was uniform in the space composed of the three contour features. This sampling ensured the equal appearance frequency of the factors and a wide variety of contour shapes including those comprised of contradictory factors that induce figure in the opposite directions. This sampling from natural contours is advantageous in order to randomly pickup a variety of contours that satisfy a wide range of cue combinations. Multidimensional scaling analyses showed that the combinations of convexity, closure, and symmetry contribute to perceptual similarity, thus they are perceptual quantities. Second, we examined whether the three features contribute to local figure-ground perception. We performed psychophysical experiments to judge the direction of the figure along the local contours, and examined the contribution of the features to the figure-ground judgment. Multiple linear regression analyses showed that closure was a significant factor, but that convexity and symmetry were not. These results indicate that closure is dominant in the local figure-ground perception with natural contours when the other cues coexist with equal probability including contradictory cases.

Discriminant Features and Temporal Structure of Nonmanuals in American Sign Language

PubMed Central

Benitez-Quiroz, C. Fabian; Gökgöz, Kadir; Wilbur, Ronnie B.; Martinez, Aleix M.

2014-01-01

To fully define the grammar of American Sign Language (ASL), a linguistic model of its nonmanuals needs to be constructed. While significant progress has been made to understand the features defining ASL manuals, after years of research, much still needs to be done to uncover the discriminant nonmanual components. The major barrier to achieving this goal is the difficulty in correlating facial features and linguistic features, especially since these correlations may be temporally defined. For example, a facial feature (e.g., head moves down) occurring at the end of the movement of another facial feature (e.g., brows moves up), may specify a Hypothetical conditional, but only if this time relationship is maintained. In other instances, the single occurrence of a movement (e.g., brows move up) can be indicative of the same grammatical construction. In the present paper, we introduce a linguistic–computational approach to efficiently carry out this analysis. First, a linguistic model of the face is used to manually annotate a very large set of 2,347 videos of ASL nonmanuals (including tens of thousands of frames). Second, a computational approach is used to determine which features of the linguistic model are more informative of the grammatical rules under study. We used the proposed approach to study five types of sentences – Hypothetical conditionals, Yes/no questions, Wh-questions, Wh-questions postposed, and Assertions – plus their polarities – positive and negative. Our results verify several components of the standard model of ASL nonmanuals and, most importantly, identify several previously unreported features and their temporal relationship. Notably, our results uncovered a complex interaction between head position and mouth shape. These findings define some temporal structures of ASL nonmanuals not previously detected by other approaches. PMID:24516528

Opinion comparison concerning future information technology in Finnish community pharmacies.

PubMed

Westerling, Anna Marietta; Hynninen, Jaana Tuulikki; Haikala, Veikko Ewald; Airaksinen, Marja S

2010-12-01

To compare the opinions of community pharmacy owners, managers and personnel concerning the key features of the future information technology system needed in Finnish community pharmacies. The study was targeted to the pharmacists working in community pharmacies as managers (owners and staff pharmacists with M.Sc. degree) or personnel responsible for dispensing and patient counselling (pharmacists with B.Sc. degree). A national cross-sectional survey to all of Finnish community pharmacy owners (n = 580) and staff pharmacists (B.Sc. and M.Sc. degrees, n = 1709) working in community pharmacies, was conducted in order to determine differences in opinions between these occupation groups with different professional duties. The response rates were 53% for pharmacy owners (n = 308) and 22% for staff pharmacists (n = 373). The main outcome measure was the perceived importance of 89 potential features for a new IT system ranked by using a five-point Likert scale. The responding community pharmacy managers and staff pharmacists had differences in their ranking of more than half (52%) of the potential features listed in the survey questionnaire. The features related to the pharmacy's internal processes, such as financial management, sales and marketing management and stock holding, were ranked significantly higher by the managers, while the personnel prioritized the features supporting pharmaceutical service provision and personnel management. The managers and personnel shared their opinion on the importance of features supporting drug information and patient counselling, medication safety and interprofessional collaboration. The managers and staff pharmacists have different views of the importance of IT features, reflecting their different professional duties in the community pharmacy. A high priority was given for the features familiar to the users and needed in their daily practice. This indicates the need for involving different occupation groups in planning the new IT systems for community pharmacies.

EEG source space analysis of the supervised factor analytic approach for the classification of multi-directional arm movement

NASA Astrophysics Data System (ADS)

Shenoy Handiru, Vikram; Vinod, A. P.; Guan, Cuntai

2017-08-01

Objective. In electroencephalography (EEG)-based brain-computer interface (BCI) systems for motor control tasks the conventional practice is to decode motor intentions by using scalp EEG. However, scalp EEG only reveals certain limited information about the complex tasks of movement with a higher degree of freedom. Therefore, our objective is to investigate the effectiveness of source-space EEG in extracting relevant features that discriminate arm movement in multiple directions. Approach. We have proposed a novel feature extraction algorithm based on supervised factor analysis that models the data from source-space EEG. To this end, we computed the features from the source dipoles confined to Brodmann areas of interest (BA4a, BA4p and BA6). Further, we embedded class-wise labels of multi-direction (multi-class) source-space EEG to an unsupervised factor analysis to make it into a supervised learning method. Main Results. Our approach provided an average decoding accuracy of 71% for the classification of hand movement in four orthogonal directions, that is significantly higher (>10%) than the classification accuracy obtained using state-of-the-art spatial pattern features in sensor space. Also, the group analysis on the spectral characteristics of source-space EEG indicates that the slow cortical potentials from a set of cortical source dipoles reveal discriminative information regarding the movement parameter, direction. Significance. This study presents evidence that low-frequency components in the source space play an important role in movement kinematics, and thus it may lead to new strategies for BCI-based neurorehabilitation.

Measuring how typical and atypical minds read other's intentions. Comment on "Seeing mental states: An experimental strategy for measuring the observability of other minds" by Cristina Becchio et al.

NASA Astrophysics Data System (ADS)

Parma, Valentina; Sartori, Luisa; Castiello, Umberto

2018-03-01

Becchio et al. [1] propose a model to render other's minds observable against the Unobservability Principle. Such model develops over four, distinct steps. First, it provides experimental evidence indicating that mental states (i.e., intentions) can be encoded in behavioral patterns (e.g., movement kinematics). Second, it provides strategies to test the efficiency of the quantification of such intention-related behavioral manifestations (i.e., resolution of the uncertainty between two intentions based on different patterns of accumulation of kinematic parameters). Third, it indicates specific features of the observed behavior that viewers use to detect different intentions (i.e., a series of decision rules based on kinematic features through which intention categorization occurs). Fourth, it proposes a manner to manipulate such specific behavioral features so that an observer can detect different intentions, based on how informative such behavioral features are. We see in this operational/experimental approach a significant contribution to the theoretical debate on the possibility to observe mental states, allowing the direct testing of the unobservability principle and therefore providing falsifiable hypotheses. Besides this already central aspect, we believe this approach holds promise to the elucidation of clinical open questions, such as those posed by autism spectrum disorders (ASD). Indeed, experimentally evaluating the ability to observe and manipulate other's intentions allow us to quantify with high accuracy the deficits in the representation of other people's minds that so chiefly characterize ASD as well as the outcomes of treatment options focusing on this aspect. Here we suggest a few clarifications and extensions of the proposed model which will make it possibly tailored for clinical applications.

Identifying and Prioritizing Greater Sage-Grouse Nesting and Brood-Rearing Habitat for Conservation in Human-Modified Landscapes

PubMed Central

Dzialak, Matthew R.; Olson, Chad V.; Harju, Seth M.; Webb, Stephen L.; Mudd, James P.; Winstead, Jeffrey B.; Hayden-Wing, L.D.

2011-01-01

Background Balancing animal conservation and human use of the landscape is an ongoing scientific and practical challenge throughout the world. We investigated reproductive success in female greater sage-grouse (Centrocercus urophasianus) relative to seasonal patterns of resource selection, with the larger goal of developing a spatially-explicit framework for managing human activity and sage-grouse conservation at the landscape level. Methodology/Principal Findings We integrated field-observation, Global Positioning Systems telemetry, and statistical modeling to quantify the spatial pattern of occurrence and risk during nesting and brood-rearing. We linked occurrence and risk models to provide spatially-explicit indices of habitat-performance relationships. As part of the analysis, we offer novel biological information on resource selection during egg-laying, incubation, and night. The spatial pattern of occurrence during all reproductive phases was driven largely by selection or avoidance of terrain features and vegetation, with little variation explained by anthropogenic features. Specifically, sage-grouse consistently avoided rough terrain, selected for moderate shrub cover at the patch level (within 90 m2), and selected for mesic habitat in mid and late brood-rearing phases. In contrast, risk of nest and brood failure was structured by proximity to anthropogenic features including natural gas wells and human-created mesic areas, as well as vegetation features such as shrub cover. Conclusions/Significance Risk in this and perhaps other human-modified landscapes is a top-down (i.e., human-mediated) process that would most effectively be minimized by developing a better understanding of specific mechanisms (e.g., predator subsidization) driving observed patterns, and using habitat-performance indices such as those developed herein for spatially-explicit guidance of conservation intervention. Working under the hypothesis that industrial activity structures risk by enhancing predator abundance or effectiveness, we offer specific recommendations for maintaining high-performance habitat and reducing low-performance habitat, particularly relative to the nesting phase, by managing key high-risk anthropogenic features such as industrial infrastructure and water developments. PMID:22022587

Features of Inner Structure of Placer Gold of the North-Eastern Part Siberian Platform

NASA Astrophysics Data System (ADS)

Gerasimov, Boris; Zhuravlev, Anatolii; Ivanov, Alexey

2017-12-01

Mineral and raw material base of placer and ore gold is based on prognosis evaluation, which allows to define promising areas regarding gold-bearing deposit prospecting. But there are some difficulties in gold primary source predicting and prospecting at the North-east Siberian platform, because the studied area is overlapped by thick cover of the Cenozoic deposits, where traditional methods of gold deposit prospecting are ineffective. In this connection, detailed study of typomorphic features of placer gold is important, because it contains key genetic information, necessary for development of mineralogical criteria of prognosis evaluation of ore gold content. Authors studied mineralogical-geochemical features of placer gold of the Anabar placer area for 15 years, with a view to identify indicators of gold, typical for different formation types of primary sources. This article presents results of these works. In placer regions, where primary sources of gold are not identified, there is need to study typomorphic features of placer gold, because it contains important genetic information, necessary for the development of mineralogical criteria of prognosis evaluation of ore gold content. Inner structures of gold from the Anabar placer region are studied, as one of the diagnostic typomorphic criteria as described in prominent method, developed by N.V. Petrovskaya [1980]. Etching of gold was carried out using reagent: HCl + HNO3 + FeCl3 × 6H2O + CrO3 +thioureat + water. Identified inner structures wer studied in details by means of scanning electron microscope JEOL JSM-6480LV. Two types of gold are identified according to the features of inner structure of placer gold of the Anabar region. First type - medium-high karat fine, well processed gold with significantly changed inner structure. This gold is allochthonous, which was redeposited many times from ancient intermediate reservoirs to younger deposits. Second type - low-medium karat, poorly rounded gold with unchanged inner structure. Poor roundness of gold particles and preservation of their primary inner structures indicate close proximity of primary source.

General geology and geomorphology of the Mars Pathfinder landing site

USGS Publications Warehouse

Ward, A.W.; Gaddis, L.R.; Kirk, R.L.; Soderblom, L.A.; Tanaka, K.L.; Golombek, M.P.; Parker, T.J.; Greeley, Ronald; Kuzmin, R.O.

1999-01-01

The Mars Pathfinder (MPF) spacecraft landed on relatively young (late Hesperian-early Amazonian; 3.1-0.7 Ga) plains in Chryse Planitia near the mouth of Ares Vallis. Images returned from the spacecraft reveal a complex landscape of ridges and troughs, large hills and crater rims, rocks and boulders of various sizes and shapes, and surficial deposits, indicating a complex, multistage geologic history of the landing site. After the deposition of one or more bedrock units, depositional and erosional fluvial processes shaped much of the present landscape. Multiple erosional events are inferred on the basis of observations of numerous channels, different orientations of many streamlined tails from their associated knobs and hills, and superposition of lineations and streamlines. Medium- and small-scale features, interpreted to be related to late-stage drainage of floodwaters, are recognized in several areas at the landing site. Streamlined knobs and hills seen in Viking orbiter images support this inference, as they seem to be complex forms, partly erosional and partly depositional, and may also indicate a series of scouring and depositional events that, in some cases, further eroded or partially buried these landforms. Although features such as these are cited as evidence for catastrophic flooding at Ares Vallis, some of these features may also be ascribed to alternative primary or secondary depositional processes, such as glacial or mass-wasting processes. Close inspection of the landing site reveals rocks that are interpreted to be volcanic in origin and others that may be conglomeratic. If such sedimentary rocks are confirmed, fluvial processes have had a greater significance on Mars than previously thought. For the last several hundred million to few billion years, eolian processes have been dominant. Dunes and dune-like features, ventifacts, and deflation and exhumation features around several rocks probably are the most recent landforms. The relatively pristine nature of the overall landscape at the MPF site suggests weathering and erosion processes on Mars are exceptionally slow.

Features of asthma which provide meaningful insights for understanding the disease heterogeneity.

PubMed

Deliu, M; Yavuz, T S; Sperrin, M; Belgrave, D; Sahiner, U M; Sackesen, C; Kalayci, O; Custovic, A

2018-01-01

Data-driven methods such as hierarchical clustering (HC) and principal component analysis (PCA) have been used to identify asthma subtypes, with inconsistent results. To develop a framework for the discovery of stable and clinically meaningful asthma subtypes. We performed HC in a rich data set from 613 asthmatic children, using 45 clinical variables (Model 1), and after PCA dimensionality reduction (Model 2). Clinical experts then identified a set of asthma features/domains which informed clusters in the two analyses. In Model 3, we reclustered the data using these features to ascertain whether this improved the discovery process. Cluster stability was poor in Models 1 and 2. Clinical experts highlighted four asthma features/domains which differentiated the clusters in two models: age of onset, allergic sensitization, severity, and recent exacerbations. In Model 3 (HC using these four features), cluster stability improved substantially. The cluster assignment changed, providing more clinically interpretable results. In a 5-cluster model, we labelled the clusters as: "Difficult asthma" (n = 132); "Early-onset mild atopic" (n = 210); "Early-onset mild non-atopic: (n = 153); "Late-onset" (n = 105); and "Exacerbation-prone asthma" (n = 13). Multinomial regression demonstrated that lung function was significantly diminished among children with "Difficult asthma"; blood eosinophilia was a significant feature of "Difficult," "Early-onset mild atopic," and "Late-onset asthma." Children with moderate-to-severe asthma were present in each cluster. An integrative approach of blending the data with clinical expert domain knowledge identified four features, which may be informative for ascertaining asthma endotypes. These findings suggest that variables which are key determinants of asthma presence, severity, or control may not be the most informative for determining asthma subtypes. Our results indicate that exacerbation-prone asthma may be a separate asthma endotype and that severe asthma is not a single entity, but an extreme end of the spectrum of several different asthma endotypes. © 2017 The Authors. Clinical & Experimental Allergy published by John Wiley & Sons Ltd.

DEVELOPMENT OF RIPARIAN ZONE INDICATORS (INT. GRANT)

EPA Science Inventory

Landscape features (e.g., land use) influence water quality characteristics on a variety of spatial scales. For example, while land use is controlled by anthropogenic features at a local scale, geologic features are set at larger spatial, and longer temporal scales. Individual ...

Assessing the performance of quantitative image features on early stage prediction of treatment effectiveness for ovary cancer patients: a preliminary investigation

NASA Astrophysics Data System (ADS)

Zargari, Abolfazl; Du, Yue; Thai, Theresa C.; Gunderson, Camille C.; Moore, Kathleen; Mannel, Robert S.; Liu, Hong; Zheng, Bin; Qiu, Yuchen

2018-02-01

The objective of this study is to investigate the performance of global and local features to better estimate the characteristics of highly heterogeneous metastatic tumours, for accurately predicting the treatment effectiveness of the advanced stage ovarian cancer patients. In order to achieve this , a quantitative image analysis scheme was developed to estimate a total of 103 features from three different groups including shape and density, Wavelet, and Gray Level Difference Method (GLDM) features. Shape and density features are global features, which are directly applied on the entire target image; wavelet and GLDM features are local features, which are applied on the divided blocks of the target image. To assess the performance, the new scheme was applied on a retrospective dataset containing 120 recurrent and high grade ovary cancer patients. The results indicate that the three best performed features are skewness, root-mean-square (rms) and mean of local GLDM texture, indicating the importance of integrating local features. In addition, the averaged predicting performance are comparable among the three different categories. This investigation concluded that the local features contains at least as copious tumour heterogeneity information as the global features, which may be meaningful on improving the predicting performance of the quantitative image markers for the diagnosis and prognosis of ovary cancer patients.

Flat Terahertz Reflective Focusing Metasurface with Scanning Ability.

PubMed

Yi, Huan; Qu, Shi-Wei; Chen, Bao-Jie; Bai, Xue; Ng, Kung Bo; Chan, Chi Hou

2017-06-14

The ability to manipulate the propagation properties of electromagnetic waves, e.g., divergence, focusing, holography or deflection, is very significant in terahertz applications. Metasurfaces with flat structures are attractive for achieving such manipulations in terahertz band, as they feature low profile, lightweight, and ease of design and installation. Several types of terahertz reflective or transmitting metasurfaces with focusing function have been implemented recently, but none of them can provide scanning ability with controllable focus. Here, a flat reflective metasurface featuring controllable focal shift is proposed and experimentally demonstrated. Furthermore, the principle of designing a focus scanning reflective metasurface is presented and the focusing characteristics are discussed, including focus scanning along a line parallel or orthogonal to the metasurface with a large bandwidth. These interesting properties indicate that this flat reflective metasurface could play a key role in many terahertz imaging and detection systems.

Effect of auditory presentation of words on color naming: the intermodal Stroop effect.

PubMed

Shimada, H

1990-06-01

To verify two hypotheses (the automatic parallel-processing model vs the feature integration theory) using the Stroop effect, an intermodal presentation method was introduced. The intermodal presentation (auditory presentation of the distractor word and visual presentation of color patch) separates completely the color and word information. Subjects were required to name the color patch on the CRT and to ignore the auditory color-word in the present experiment. A 5 (stimulus onset asynchronies) x 4 (levels of congruency) analysis of variance with repeated measures was performed on the response times. Two main effects and an interactive effect were significant. The findings indicate that without the presentation of color and word component in the same spatial location the Stroop effect occurs. These results suggest that the feature-integration theory cannot explain the mechanisms underlying the Stroop effect.

[EEG-correlates of pilots' functional condition in simulated flight dynamics].

PubMed

Kiroy, V N; Aslanyan, E V; Bakhtin, O M; Minyaeva, N R; Lazurenko, D M

2015-01-01

The spectral characteristics of the EEG recorded on two professional pilots in the simulator TU-154 aircraft in flight dynamics, including takeoff, landing and horizontal flight (in particular during difficult conditions) were analyzed. EEG recording was made with frequency band 0.1-70 Hz continuously from 15 electrodes. The EEG recordings were evaluated using analysis of variance and discriminant analysis. Statistical significant of the identified differences and the influence of the main factors and their interactions were evaluated using Greenhouse - Gaiser corrections. It was shown that the spectral characteristics of the EEG are highly informative features of the state of the pilots, reflecting the different flight phases. High validity ofthe differences including individual characteristic, indicates their non-random nature and the possibility of constructing a system of pilots' state control during all phases of flight, based on EEG features.

Experimental hypo/hyperthyroidism in rats and the perinatal development of the hypothalamo-neurohypophysial system in comparison with the thyroid gland state and external features.

PubMed

Kiessig, R; Wolf, G; Dietzmann, K

1983-05-01

Neurophysin was detected immunohistochemically in the hypothalamo-neurohypophysial system of Wistar rats not before fetal day 18. Formerly, neurophysin was identified on day 16 of intrauterine life using another breeding stock of Wistar rats, but the same immunohistochemical reagents. In pregnant rats, experimentally induced hypo/hyperthyroidism beginning with day 13 of gestation failed to show any evident influence on the first appearance of immunohistochemically detectable neurophysin during the fetal development. Otherwise, significant effects on fetal body growth and other external features as well as the fetal thyroid state and histochemically demonstrable thyroid peroxidase activity were shown. The influence of thiamazol on the fetal thyroid peroxidase points out a primary effect and indicates the permeability of the placenta to this antithyroid drug.

WebLogo: A Sequence Logo Generator

PubMed Central

Crooks, Gavin E.; Hon, Gary; Chandonia, John-Marc; Brenner, Steven E.

2004-01-01

WebLogo generates sequence logos, graphical representations of the patterns within a multiple sequence alignment. Sequence logos provide a richer and more precise description of sequence similarity than consensus sequences and can rapidly reveal significant features of the alignment otherwise difficult to perceive. Each logo consists of stacks of letters, one stack for each position in the sequence. The overall height of each stack indicates the sequence conservation at that position (measured in bits), whereas the height of symbols within the stack reflects the relative frequency of the corresponding amino or nucleic acid at that position. WebLogo has been enhanced recently with additional features and options, to provide a convenient and highly configurable sequence logo generator. A command line interface and the complete, open WebLogo source code are available for local installation and customization. PMID:15173120

Endoglin (CD105) expression on microvessel endothelial cells in juvenile nasopharyngeal angiofibroma: tissue microarray analysis and association with prognostic significance.

PubMed

Wang, Jing-Jing; Sun, Xi-Cai; Hu, Li; Liu, Zhuo-Fu; Yu, Hua-Peng; Li, Han; Wang, Shu-Yi; Wang, De-Hui

2013-12-01

The purpose of this study was to examine endoglin (CD105) expression on microvessel endothelial cells (ECs) in juvenile nasopharyngeal angiofibroma (JNA) and its relationship with recurrence. Immunohistochemistry was performed to detect CD105 expression in a tissue microarray from 70 patients with JNA. Correlation between CD105 expression on microvessel ECs and clinicopathological features, as well as tumor recurrence, were analyzed. Immunohistochemistry revealed CD105 expression on ECs but not in stroma of patients with JNA. Chi-square analysis indicated CD105-based microvessel density (MVD) was correlated with JNA recurrence (p = .013). Univariate and multivariate analyses determined that MVD was a significant predictor of time to recurrence (p = .009). The CD105-based MVD was better for predicting disease recurrence (AUROC: 0.673; p = .036) than other clinicopathological features. MVD is a useful predictor for poor prognosis of patients with JNA after curative resection. Angiogenesis, which may play an important role in the occurrence and development of JNA, is therefore a potential therapeutic target for JNA. Copyright © 2013 Wiley Periodicals, Inc., A Wiley Company.

Ambient noise causes independent changes in distinct spectro-temporal features of echolocation calls in horseshoe bats.

PubMed

Hage, Steffen R; Jiang, Tinglei; Berquist, Sean W; Feng, Jiang; Metzner, Walter

2014-07-15

One of the most efficient mechanisms to optimize signal-to-noise ratios is the Lombard effect - an involuntary rise in call amplitude due to ambient noise. It is often accompanied by changes in the spectro-temporal composition of calls. We examined the effects of broadband-filtered noise on the spectro-temporal composition of horseshoe bat echolocation calls, which consist of a constant-frequency component and initial and terminal frequency-modulated components. We found that the frequency-modulated components became larger for almost all noise conditions, whereas the bandwidth of the constant-frequency component increased only when broadband-filtered noise was centered on or above the calls' dominant or fundamental frequency. This indicates that ambient noise independently modifies the associated acoustic parameters of the Lombard effect, such as spectro-temporal features, and could significantly affect the bat's ability to detect and locate targets. Our findings may be of significance in evaluating the impact of environmental noise on echolocation behavior in bats. © 2014. Published by The Company of Biologists Ltd.

Syn-deformational features of Carlin-type Au deposits

USGS Publications Warehouse

Peters, S.G.

2004-01-01

Syn-deformational ore deposition played an important role in some Carlin-type Au deposits according to field and laboratory evidence, which indicates that flow of Au-bearing fluids was synchronous with regional-scale deformation events. Gold-related deformation events linked to ore genesis were distinct from high-level, brittle deformation that is typical of many epithermal deposits. Carlin-type Au deposits, with brittle-ductile features, most likely formed during tectonic events that were accompanied by significant fluid flow. Interactive deformation-fluid processes involved brittle-ductile folding, faulting, shearing, and gouge development that were focused along illite-clay and dissolution zones caused by hydrothermal alteration. Alteration along these deformation zones resulted in increased porosity and enhancement of fluid flow, which resulted in decarbonated, significant dissolution, collapse, and volume and mass reduction. Carlin-type Au deposits commonly are hosted in Paleozoic and Mesozoic sedimentary rocks (limestone, siltstone, argillite, shale, and quartzite) on the margins of cratons. The sedimentary basins containing the host rocks underwent tectonic events that influenced the development of stratabound, structurally controlled orebodies. Published by Elsevier Ltd.

Resolving the homology—function relationship through comparative genomics of membrane-trafficking machinery and parasite cell biology

PubMed Central

Klinger, Christen M.; Ramirez-Macias, Inmaculada; Herman, Emily K.; Turkewitz, Aaron P.; Field, Mark C.; Dacks, Joel B.

2016-01-01

With advances in DNA sequencing technology, it is increasingly common and tractable to informatically look for genes of interest in the genomic databases of parasitic organisms and infer cellular states. Assignment of a putative gene function based on homology to functionally characterized genes in other organisms, though powerful, relies on the implicit assumption of functional homology, i.e. that orthology indicates conserved function. Eukaryotes reveal a dazzling array of cellular features and structural organization, suggesting a concomitant diversity in their underlying molecular machinery. Significantly, examples of novel functions for pre-existing or new paralogues are not uncommon. Do these examples undermine the basic assumption of functional homology, especially in parasitic protists, which are often highly derived? Here we examine the extent to which functional homology exists between organisms spanning the eukaryotic lineage. By comparing membrane trafficking proteins between parasitic protists and traditional model organisms, where direct functional evidence is available, we find that function is indeed largely conserved between orthologues, albeit with significant adaptation arising from the unique biological features within each lineage. PMID:27444378

Biomass saccharification is largely enhanced by altering wall polymer features and reducing silicon accumulation in rice cultivars harvested from nitrogen fertilizer supply.

PubMed

Zahoor; Sun, Dan; Li, Ying; Wang, Jing; Tu, Yuanyuan; Wang, Yanting; Hu, Zhen; Zhou, Shiguang; Wang, Lingqiang; Xie, Guosheng; Huang, Jianliang; Alam, Aftab; Peng, Liangcai

2017-11-01

In this study, two rice cultivars were collected from experimental fields with seven nitrogen fertilizer treatments. All biomass samples contained significantly increased cellulose contents and reduced silica levels, with variable amounts of hemicellulose and lignin from different nitrogen treatments. Under chemical (NaOH, CaO, H 2 SO 4 ) and physical (hot water) pretreatments, biomass samples exhibited much enhanced hexoses yields from enzymatic hydrolysis, with high bioethanol production from yeast fermentation. Notably, both degree of polymerization (DP) of cellulose and xylose/arabinose (Xyl/Ara) ratio of hemicellulose were reduced in biomass residues, whereas other wall polymer features (cellulose crystallinity and monolignol proportion) were variable. Integrative analysis indicated that cellulose DP, hemicellulosic Xyl/Ara and silica are the major factors that significantly affect cellulose crystallinity and biomass saccharification. Hence, this study has demonstrated that nitrogen fertilizer supply could largely enhance biomass saccharification in rice cultivars, mainly by reducing cellulose DP, hemicellulosic Xyl/Ara and silica in cell walls. Copyright © 2017 Elsevier Ltd. All rights reserved.

Driver fatigue detection through multiple entropy fusion analysis in an EEG-based system.

PubMed

Min, Jianliang; Wang, Ping; Hu, Jianfeng

2017-01-01

Driver fatigue is an important contributor to road accidents, and fatigue detection has major implications for transportation safety. The aim of this research is to analyze the multiple entropy fusion method and evaluate several channel regions to effectively detect a driver's fatigue state based on electroencephalogram (EEG) records. First, we fused multiple entropies, i.e., spectral entropy, approximate entropy, sample entropy and fuzzy entropy, as features compared with autoregressive (AR) modeling by four classifiers. Second, we captured four significant channel regions according to weight-based electrodes via a simplified channel selection method. Finally, the evaluation model for detecting driver fatigue was established with four classifiers based on the EEG data from four channel regions. Twelve healthy subjects performed continuous simulated driving for 1-2 hours with EEG monitoring on a static simulator. The leave-one-out cross-validation approach obtained an accuracy of 98.3%, a sensitivity of 98.3% and a specificity of 98.2%. The experimental results verified the effectiveness of the proposed method, indicating that the multiple entropy fusion features are significant factors for inferring the fatigue state of a driver.

Motor knowledge is one dimension for concept organization: further evidence from a Chinese semantic dementia case.

PubMed

Lin, Nan; Guo, Qihao; Han, Zaizhu; Bi, Yanchao

2011-11-01

Neuropsychological and neuroimaging studies have indicated that motor knowledge is one potential dimension along which concepts are organized. Here we present further direct evidence for the effects of motor knowledge in accounting for categorical patterns across object domains (living vs. nonliving) and grammatical domains (nouns vs. verbs), as well as the integrity of other modality-specific knowledge (e.g., visual). We present a Chinese case, XRK, who suffered from semantic dementia with left temporal lobe atrophy. In naming and comprehension tasks, he performed better at nonliving items than at living items, and better at verbs than at nouns. Critically, multiple regression method revealed that these two categorical effects could be both accounted for by the charade rating, a continuous measurement of the significance of motor knowledge for a concept or a semantic feature. Furthermore, charade rating also predicted his performances on the generation frequency of semantic features of various modalities. These findings consolidate the significance of motor knowledge in conceptual organization and further highlights the interactions between different types of semantic knowledge. Copyright © 2010 Elsevier Inc. All rights reserved.

SSAW: A new sequence similarity analysis method based on the stationary discrete wavelet transform.

PubMed

Lin, Jie; Wei, Jing; Adjeroh, Donald; Jiang, Bing-Hua; Jiang, Yue

2018-05-02

Alignment-free sequence similarity analysis methods often lead to significant savings in computational time over alignment-based counterparts. A new alignment-free sequence similarity analysis method, called SSAW is proposed. SSAW stands for Sequence Similarity Analysis using the Stationary Discrete Wavelet Transform (SDWT). It extracts k-mers from a sequence, then maps each k-mer to a complex number field. Then, the series of complex numbers formed are transformed into feature vectors using the stationary discrete wavelet transform. After these steps, the original sequence is turned into a feature vector with numeric values, which can then be used for clustering and/or classification. Using two different types of applications, namely, clustering and classification, we compared SSAW against the the-state-of-the-art alignment free sequence analysis methods. SSAW demonstrates competitive or superior performance in terms of standard indicators, such as accuracy, F-score, precision, and recall. The running time was significantly better in most cases. These make SSAW a suitable method for sequence analysis, especially, given the rapidly increasing volumes of sequence data required by most modern applications.

Laterality versus jumping performance in men and women.

PubMed

Trzaskoma, Zbigniew; Ilnicka, Lidia; Wiszomirska, Ida; Wit, Andrzej; Wychowański, Michał

2015-01-01

The aim of this study was to investigate relationships between functional asymmetry of lower limbs, taking into account morphological features of the feet, and jumping ability in men and women. The study population consisted of 56 subjects, 30 women (age: 20.29 ± 0.59 years; body mass: 58.13 ± 4.58 kg, body height: 165.60 ± 5.03 cm) and 26 men (age: 20.41 ± 0.78 years, body mass: 78.39 ± 8.42 kg, body height: 181.15 ± 6.52 cm). The measurements of longitudinal arches were performed with the plan- tographic method on the basis of Clarke's angle mapped on a computer foot print. The measurements of jumping performance during bilateral (two legs) and unilateral (single-leg) counter movement jump (CMJ) were done on force plate. All subjects jumped three times each type of jump (total 9 jumps): three right leg, three left leg and three two legs. We put the test results through a detailed statistical analysis with the Statistica 8.0. The t-test for dependent variables and the Wilcoxon signed-rank test for divergent variances of the fea- tures compared. The analysis of relationships between the chosen podometric and plantographic features and jumping performance was conducted on the basis of the Pearson product-moment correlation coefficient (for the features which presented normal distribution, according to the Shapiro-Wilk test). The correlations between values of height of single-leg jumps (right and left) and bilateral jumps, and foot indices were found in few cases only in men who had greater values of jump height with the non-dominant limb. We did not find a significant difference in jumping ability between the dominant limb and the non-dominant limb in women. We found bilateral deficits in jumping ability in the study groups, though we did not find significant differences (P ≤ 0.05) between the values for women (a mean of 6.5%) and for men (a mean of 8.4%). We found significant gender differences of the correlations between the values of height of jumps (single-leg and bilateral jumps) and foot indices.

Automated detection and location of indications in eddy current signals

DOEpatents

Brudnoy, David M.; Oppenlander, Jane E.; Levy, Arthur J.

2000-01-01

A computer implemented information extraction process that locates and identifies eddy current signal features in digital point-ordered signals, signals representing data from inspection of test materials, by enhancing the signal features relative to signal noise, detecting features of the signals, verifying the location of the signal features that can be known in advance, and outputting information about the identity and location of all detected signal features.

Parallel perceptual enhancement and hierarchic relevance evaluation in an audio-visual conjunction task.

PubMed

Potts, Geoffrey F; Wood, Susan M; Kothmann, Delia; Martin, Laura E

2008-10-21

Attention directs limited-capacity information processing resources to a subset of available perceptual representations. The mechanisms by which attention selects task-relevant representations for preferential processing are not fully known. Triesman and Gelade's [Triesman, A., Gelade, G., 1980. A feature integration theory of attention. Cognit. Psychol. 12, 97-136.] influential attention model posits that simple features are processed preattentively, in parallel, but that attention is required to serially conjoin multiple features into an object representation. Event-related potentials have provided evidence for this model showing parallel processing of perceptual features in the posterior Selection Negativity (SN) and serial, hierarchic processing of feature conjunctions in the Frontal Selection Positivity (FSP). Most prior studies have been done on conjunctions within one sensory modality while many real-world objects have multimodal features. It is not known if the same neural systems of posterior parallel processing of simple features and frontal serial processing of feature conjunctions seen within a sensory modality also operate on conjunctions between modalities. The current study used ERPs and simultaneously presented auditory and visual stimuli in three task conditions: Attend Auditory (auditory feature determines the target, visual features are irrelevant), Attend Visual (visual features relevant, auditory irrelevant), and Attend Conjunction (target defined by the co-occurrence of an auditory and a visual feature). In the Attend Conjunction condition when the auditory but not the visual feature was a target there was an SN over auditory cortex, when the visual but not auditory stimulus was a target there was an SN over visual cortex, and when both auditory and visual stimuli were targets (i.e. conjunction target) there were SNs over both auditory and visual cortex, indicating parallel processing of the simple features within each modality. In contrast, an FSP was present when either the visual only or both auditory and visual features were targets, but not when only the auditory stimulus was a target, indicating that the conjunction target determination was evaluated serially and hierarchically with visual information taking precedence. This indicates that the detection of a target defined by audio-visual conjunction is achieved via the same mechanism as within a single perceptual modality, through separate, parallel processing of the auditory and visual features and serial processing of the feature conjunction elements, rather than by evaluation of a fused multimodal percept.

SHBG Is an Important Factor in Stemness Induction of Cells by DHT In Vitro and Associated with Poor Clinical Features of Prostate Carcinomas

PubMed Central

Ma, Yuanyuan; Liang, Dongming; Liu, Jian; Wen, Jian-Guo; Servoll, Einar; Waaler, Gudmund; Sæter, Thorstein; Axcrona, Karol; Vlatkovic, Ljiljana; Axcrona, Ulrika; Paus, Elisabeth; Yang, Yue; Zhang, Zhiqian; Kvalheim, Gunnar; Nesland, Jahn M.; Suo, Zhenhe

2013-01-01

Androgen plays a vital role in prostate cancer development. However, it is not clear whether androgens influence stem-like properties of prostate cancer, a feature important for prostate cancer progression. In this study, we show that upon DHT treatment in vitro, prostate cancer cell lines LNCaP and PC-3 were revealed with higher clonogenic potential and higher expression levels of stemness related factors CD44, CD90, Oct3/4 and Nanog. Moreover, sex hormone binding globulin (SHBG) was also simultaneously upregulated in these cells. When the SHBG gene was blocked by SHBG siRNA knock-down, the induction of Oct3/4, Nanog, CD44 and CD90 by DHT was also correspondingly blocked in these cells. Immunohistochemical evaluation of clinical samples disclosed weakly positive, and areas negative for SHBG expression in the benign prostate tissues, while most of the prostate carcinomas were strongly positive for SHBG. In addition, higher levels of SHBG expression were significantly associated with higher Gleason score, more seminal vesicle invasions and lymph node metastases. Collectively, our results show a role of SHBG in upregulating stemness of prostate cancer cells upon DHT exposure in vitro, and SHBG expression in prostate cancer samples is significantly associated with poor clinicopathological features, indicating a role of SHBG in prostate cancer progression. PMID:23936228

Morphological texture assessment of oral bone as a screening tool for osteoporosis

NASA Astrophysics Data System (ADS)

Analoui, Mostafa; Eggertsson, Hafsteinn; Eckert, George

2001-07-01

Three classes of texture analysis approaches have been employed to assess the textural characteristic of oral bone. A set of linear structuring elements was used to compute granulometric features of trabecular bone. Multifractal analysis was also used to compute the fractal dimension of the corresponding tissues. In addition, some statistical features and histomorphometric parameters were computed. To assess the proposed approach we acquired digital intraoral radiographs of 47 subjects (14 males and 33 females). All radiographs were captured at 12 bits/pixel. Images were converted to binary form through a sliding locally adaptive thresholding approach. Each subject was scanned by DEXA for bone dosimetry. Subject were classified into one of the following three categories according World Health Organization (WHO) standard (1) healthy, (2) with osteopenia and (3) osteoporosis. In this study fractal dimension showed very low correlation with bone mineral density (BMD) measurements, which did not reach a level of statistical significance (p<0.5). However, entropy of pattern spectrum (EPS), along with statistical features and histomorphometric parameters, has shown correlation coefficients ranging from low to high, with statistical significance for both males and females. The results of this study indicate the utility of this approach for bone texture analysis. It is conjectured that designing a 2-D structuring element, specially tuned to trabecular bone texture, will increase the efficacy of the proposed method.

Repetition Is the Feature Behind the Attentional Bias for Recognizing Threatening Patterns.

PubMed

Shabbir, Maryam; Zon, Adelynn M Y; Thuppil, Vivek

2018-01-01

Animals attend to what is relevant in order to behave in an effective manner and succeed in their environments. In several nonhuman species, there is an evolved bias for attending to patterns indicative of threats in the natural environment such as dangerous animals. Because skins of many dangerous animals are typically repetitive, we propose that repetition is the key feature enabling recognition of evolutionarily important threats. The current study consists of two experiments where we measured participants' reactions to pictures of male and female models wearing clothing of various repeating (leopard skin, snakeskin, and floral print) and nonrepeating (camouflage, shiny, and plain) patterns. In Experiment 1, when models wearing patterns were presented side by side with total fixation duration as the measure, the repeating floral pattern was the most provocative, with total fixation duration significantly longer than all other patterns. Leopard and snakeskin patterns had total fixation durations that were significantly longer than the plain pattern. In Experiment 2, we employed a visual-search task where participants were required to find models wearing the various patterns in a setting of a crowded airport terminal. Participants detected leopard skin pattern and repetitive floral pattern significantly faster than two of the nonpatterned clothing styles. Our experimental findings support the hypothesis that repetition of specific visual features might facilitate target detection, especially those characterizing evolutionary important threats. Our findings that intricate, but nonthreatening repeating patterns can have similar attention-grabbing properties to animal skin patterns have important implications for the fashion industry and wildlife trade.

Serum BDNF levels in patients with gambling disorder are associated with the severity of gambling disorder and Iowa Gambling Task indices

PubMed Central

Choi, Sam-Wook; Shin, Young-Chul; Mok, Jung Yeon; Kim, Dai-Jin; Choi, Jung-Seok; Suk-Hyun Hwang, Samuel

2016-01-01

Background and aims Gambling disorder (GD) shares many similarities with substance use disorders (SUDs) in clinical, neurobiological, and neurocognitive features, including decision-making. We evaluated the relationships among, GD, decision-making, and brain-derived neurotrophic factor (BDNF), as measured by serum BDNF levels. Methods Twenty-one male patients with GD and 21 healthy sex- and age-matched control subjects were evaluated for associations between serum BDNF levels and the Problem Gambling Severity Index (PGSI), as well as between serum BDNF levels and Iowa Gambling Task (IGT) indices. Results The mean serum BDNF levels were significantly increased in patients with GD compared to healthy controls. A significant correlation between serum BDNF levels and PGSI scores was found when controlling for age, depression, and duration of GD. A significant negative correlation was obtained between serum BDNF levels and IGT improvement scores. Discussion These findings support the hypothesis that serum BDNF levels constitute a dual biomarker for the neuroendocrine changes and the severity of GD in patients. Serum BDNF level may serve as an indicator of poor decision-making performance and learning processes in GD and help to identify the common physiological underpinnings between GD and SUDs. PMID:28092195

Quantitative Analysis of {sup 18}F-Fluorodeoxyglucose Positron Emission Tomography Identifies Novel Prognostic Imaging Biomarkers in Locally Advanced Pancreatic Cancer Patients Treated With Stereotactic Body Radiation Therapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cui, Yi; Global Institution for Collaborative Research and Education, Hokkaido University, Sapporo; Song, Jie

Purpose: To identify prognostic biomarkers in pancreatic cancer using high-throughput quantitative image analysis. Methods and Materials: In this institutional review board–approved study, we retrospectively analyzed images and outcomes for 139 locally advanced pancreatic cancer patients treated with stereotactic body radiation therapy (SBRT). The overall population was split into a training cohort (n=90) and a validation cohort (n=49) according to the time of treatment. We extracted quantitative imaging characteristics from pre-SBRT {sup 18}F-fluorodeoxyglucose positron emission tomography, including statistical, morphologic, and texture features. A Cox proportional hazard regression model was built to predict overall survival (OS) in the training cohort using 162more » robust image features. To avoid over-fitting, we applied the elastic net to obtain a sparse set of image features, whose linear combination constitutes a prognostic imaging signature. Univariate and multivariate Cox regression analyses were used to evaluate the association with OS, and concordance index (CI) was used to evaluate the survival prediction accuracy. Results: The prognostic imaging signature included 7 features characterizing different tumor phenotypes, including shape, intensity, and texture. On the validation cohort, univariate analysis showed that this prognostic signature was significantly associated with OS (P=.002, hazard ratio 2.74), which improved upon conventional imaging predictors including tumor volume, maximum standardized uptake value, and total legion glycolysis (P=.018-.028, hazard ratio 1.51-1.57). On multivariate analysis, the proposed signature was the only significant prognostic index (P=.037, hazard ratio 3.72) when adjusted for conventional imaging and clinical factors (P=.123-.870, hazard ratio 0.53-1.30). In terms of CI, the proposed signature scored 0.66 and was significantly better than competing prognostic indices (CI 0.48-0.64, Wilcoxon rank sum test P<1e-6). Conclusion: Quantitative analysis identified novel {sup 18}F-fluorodeoxyglucose positron emission tomography image features that showed improved prognostic value over conventional imaging metrics. If validated in large, prospective cohorts, the new prognostic signature might be used to identify patients for individualized risk-adaptive therapy.« less

Constraining Cometary Crystal Shapes from IR Spectral Features

NASA Technical Reports Server (NTRS)

Wooden, Diane H.; Lindsay, Sean; Harker, David E.; Kelley, Michael S. P.; Woodward, Charles E.; Murphy, James Richard

2013-01-01

A major challenge in deriving the silicate mineralogy of comets is ascertaining how the anisotropic nature of forsterite crystals affects the spectral features' wavelength, relative intensity, and asymmetry. Forsterite features are identified in cometary comae near 10, 11.05-11.2, 16, 19, 23.5, 27.5 and 33 microns [1-10], so accurate models for forsterite's absorption efficiency (Qabs) are a primary requirement to compute IR spectral energy distributions (SEDs, lambdaF lambda vs. lambda) and constrain the silicate mineralogy of comets. Forsterite is an anisotropic crystal, with three crystallographic axes with distinct indices of refraction for the a-, b-, and c-axis. The shape of a forsterite crystal significantly affects its spectral features [13-16]. We need models that account for crystal shape. The IR absorption efficiencies of forsterite are computed using the discrete dipole approximation (DDA) code DDSCAT [11,12]. Starting from a fiducial crystal shape of a cube, we systematically elongate/reduce one of the crystallographic axes. Also, we elongate/reduce one axis while the lengths of the other two axes are slightly asymmetric (0.8:1.2). The most significant grain shape characteristic that affects the crystalline spectral features is the relative lengths of the crystallographic axes. The second significant grain shape characteristic is breaking the symmetry of all three axes [17]. Synthetic spectral energy distributions using seven crystal shape classes [17] are fit to the observed SED of comet C/1995 O1 (Hale-Bopp). The Hale-Bopp crystalline residual better matches equant, b-platelets, c-platelets, and b-columns spectral shape classes, while a-platelets, a-columns and c-columns worsen the spectral fits. Forsterite condensation and partial evaporation experiments demonstrate that environmental temperature and grain shape are connected [18-20]. Thus, grain shape is a potential probe for protoplanetary disk temperatures where the cometary crystalline forsterite formed. The forsterite crystal shapes (equant, b-platelets, c-platelets, b-columns - excluding a- and c-columns) derived from our modeling [17] of comet Hale- Bopp, compared to laboratory synthesis experiments [18], suggests that these crystals are high temperature condensates. By observing and modeling the crystalline features in comet ISON, we may constrain forsterite crystal shape(s) and link to their formation temperature(s) and environment(s).

Rootless Cones on Mars: A Consequence of Lava-Ground Ice Interaction

NASA Technical Reports Server (NTRS)

Fagents, S. A.; Greeley, R.; Lanagan, P.

2002-01-01

Fields of small cratered cones on Mars are interpreted to have formed by rootless eruptions due to explosive interaction of lava with ground ice contained within the regolith beneath the flow. Melting and vaporization of the ice, and subsequent explosive expansion of the vapour, act to excavate the lava and construct a rootless cone around the explosion site. Similar features are found in Iceland, where flowing lava encountered water-saturated substrates. The martian cones have basal diameters of c. 30-1000 m and are located predominantly in the northern volcanic plains. High-resolution Mars Orbiter Camera images offer significant improvements over Viking data for interpretation of cone origins. A new model of the dynamics of cone formation indicates that very modest amounts of water ice are required to initiate and sustain the explosive interactions that produced the observed features. This is consistent with the likely low availability of water ice in the martian regolith. The scarcity of impact craters on many of the host lava flows indicates very young ages, suggesting that ground ice was present as recently as less than 10 - l00 Ma, and may persist today. Rootless cones therefore act as a spatial and temporal probe of the distribution of ground ice on Mars, which is of key significance in understanding the evolution of the martian climate. The location of water in liquid or solid form is of great importance to future robotic and human exploration strategies, and to the search for extraterrestrial life.

Quantifying landscape change in an arctic coastal lowland using repeat airborne LiDAR

USGS Publications Warehouse

Jones, Benjamin M.; Stoker, Jason M.; Gibbs, Ann E.; Grosse, Guido; Romanovsky, Vladimir E.; Douglas, Thomas A.; Kinsman, Nichole E.M.; Richmond, Bruce M.

2013-01-01

Increases in air, permafrost, and sea surface temperature, loss of sea ice, the potential for increased wave energy, and higher river discharge may all be interacting to escalate erosion of arctic coastal lowland landscapes. Here we use airborne light detection and ranging (LiDAR) data acquired in 2006 and 2010 to detect landscape change in a 100 km2 study area on the Beaufort Sea coastal plain of northern Alaska. We detected statistically significant change (99% confidence interval), defined as contiguous areas (>10 m2) that had changed in height by at least 0.55 m, in 0.3% of the study region. Erosional features indicative of ice-rich permafrost degradation were associated with ice-bonded coastal, river, and lake bluffs, frost mounds, ice wedges, and thermo-erosional gullies. These features accounted for about half of the area where vertical change was detected. Inferred thermo-denudation and thermo-abrasion of coastal and river bluffs likely accounted for the dominant permafrost-related degradational processes with respect to area (42%) and volume (51%). More than 300 thermokarst pits significantly subsided during the study period, likely as a result of storm surge flooding of low-lying tundra (<1.4 m asl) as well as the lasting impact of warm summers in the late-1980s and mid-1990s. Our results indicate that repeat airborne LiDAR can be used to detect landscape change in arctic coastal lowland regions at large spatial scales over sub-decadal time periods.

Preoperative regional cerebral blood flow and postoperative clinical improvement in patients with Parkinson's disease undergoing subthalamic nucleus deep brain stimulation.

PubMed

Nagai, Toshiya; Kajita, Yasukazu; Maesawa, Satoshi; Nakatsubo, Daisuke; Yoshida, Kota; Kato, Katsuhiko; Wakabayashi, Toshihiko

2012-01-01

Preoperative regional cerebral blood flow (rCBF) was measured in 92 patients with Parkinson's disease (PD) by iodine-123 N-isopropyl-p-iodoamphetamine single-photon emission computed tomography. Quantitative mapping of rCBF was performed using the stereotactic extraction estimation method. The clinical features of the patients were assessed according to the Unified Parkinson Disease Rating Scale (UPDRS). The correlation between rCBF and improvement in the UPDRS score following surgery was examined. rCBF in the fusiform gyrus, superior and inferior parietal gyri, middle occipital gyrus, superior frontal gyrus, and middle temporal gyrus of the Talairach Daemon Level 3 was significantly correlated with UPDRS part II (off stage) and III (on stage) scores (p < 0.05). rCBF in the middle temporal gyrus (p = 0.00147), medial frontal gyrus (p = 0.00713), and cerebellum (p = 0.048) of the Talairach Daemon Level 3 was significantly greater in 47 patients with >60% improvement of UPDRS part III (off stage) score than in 37 patients with 40-60% improvement. The cutoff value of rCBF, which indicated that >40% improvement in the surgical outcome could be expected, was 38.8 ± 6.2 ml/100 g/min in the frontal lobe. This study indicated that rCBF in patients with PD might be related to their clinical features, suggesting that quantitative mapping of rCBF may be useful for predicting surgical outcome.

Utilizing Chinese Admission Records for MACE Prediction of Acute Coronary Syndrome

PubMed Central

Hu, Danqing; Huang, Zhengxing; Chan, Tak-Ming; Dong, Wei; Lu, Xudong; Duan, Huilong

2016-01-01

Background: Clinical major adverse cardiovascular event (MACE) prediction of acute coronary syndrome (ACS) is important for a number of applications including physician decision support, quality of care assessment, and efficient healthcare service delivery on ACS patients. Admission records, as typical media to contain clinical information of patients at the early stage of their hospitalizations, provide significant potential to be explored for MACE prediction in a proactive manner. Methods: We propose a hybrid approach for MACE prediction by utilizing a large volume of admission records. Firstly, both a rule-based medical language processing method and a machine learning method (i.e., Conditional Random Fields (CRFs)) are developed to extract essential patient features from unstructured admission records. After that, state-of-the-art supervised machine learning algorithms are applied to construct MACE prediction models from data. Results: We comparatively evaluate the performance of the proposed approach on a real clinical dataset consisting of 2930 ACS patient samples collected from a Chinese hospital. Our best model achieved 72% AUC in MACE prediction. In comparison of the performance between our models and two well-known ACS risk score tools, i.e., GRACE and TIMI, our learned models obtain better performances with a significant margin. Conclusions: Experimental results reveal that our approach can obtain competitive performance in MACE prediction. The comparison of classifiers indicates the proposed approach has a competitive generality with datasets extracted by different feature extraction methods. Furthermore, our MACE prediction model obtained a significant improvement by comparison with both GRACE and TIMI. It indicates that using admission records can effectively provide MACE prediction service for ACS patients at the early stage of their hospitalizations. PMID:27649220

Changes in task-based effective connectivity in language networks following rehabilitation in post-stroke patients with aphasia

PubMed Central

Kiran, Swathi; Meier, Erin L.; Kapse, Kushal J.; Glynn, Peter A.

2015-01-01

In this study, we examined regions in the left and right hemisphere language network that were altered in terms of the underlying neural activation and effective connectivity subsequent to language rehabilitation. Eight persons with chronic post-stroke aphasia and eight normal controls participated in the current study. Patients received a 10 week semantic feature-based rehabilitation program to improve their skills. Therapy was provided on atypical examples of one trained category while two control categories were monitored; the categories were counterbalanced across patients. In each fMRI session, two experimental tasks were conducted: (a) picture naming and (b) semantic feature verification of trained and untrained categories. Analysis of treatment effect sizes revealed that all patients showed greater improvements on the trained category relative to untrained categories. Results from this study show remarkable patterns of consistency despite the inherent variability in lesion size and activation patterns across patients. Across patients, activation that emerged as a function of rehabilitation on the trained category included bilateral IFG, bilateral SFG, LMFG, and LPCG for picture naming; and bilateral IFG, bilateral MFG, LSFG, and bilateral MTG for semantic feature verification. Analysis of effective connectivity using Dynamic Causal Modeling (DCM) indicated that LIFG was the consistently significantly modulated region after rehabilitation across participants. These results indicate that language networks in patients with aphasia resemble normal language control networks and that this similarity is accentuated by rehabilitation. PMID:26106314

Infrared and visual image fusion method based on discrete cosine transform and local spatial frequency in discrete stationary wavelet transform domain

NASA Astrophysics Data System (ADS)

Jin, Xin; Jiang, Qian; Yao, Shaowen; Zhou, Dongming; Nie, Rencan; Lee, Shin-Jye; He, Kangjian

2018-01-01

In order to promote the performance of infrared and visual image fusion and provide better visual effects, this paper proposes a hybrid fusion method for infrared and visual image by the combination of discrete stationary wavelet transform (DSWT), discrete cosine transform (DCT) and local spatial frequency (LSF). The proposed method has three key processing steps. Firstly, DSWT is employed to decompose the important features of the source image into a series of sub-images with different levels and spatial frequencies. Secondly, DCT is used to separate the significant details of the sub-images according to the energy of different frequencies. Thirdly, LSF is applied to enhance the regional features of DCT coefficients, and it can be helpful and useful for image feature extraction. Some frequently-used image fusion methods and evaluation metrics are employed to evaluate the validity of the proposed method. The experiments indicate that the proposed method can achieve good fusion effect, and it is more efficient than other conventional image fusion methods.

Knee Joint Vibration Signal Analysis with Matching Pursuit Decomposition and Dynamic Weighted Classifier Fusion

PubMed Central

Cai, Suxian; Yang, Shanshan; Zheng, Fang; Lu, Meng; Wu, Yunfeng; Krishnan, Sridhar

2013-01-01

Analysis of knee joint vibration (VAG) signals can provide quantitative indices for detection of knee joint pathology at an early stage. In addition to the statistical features developed in the related previous studies, we extracted two separable features, that is, the number of atoms derived from the wavelet matching pursuit decomposition and the number of significant signal turns detected with the fixed threshold in the time domain. To perform a better classification over the data set of 89 VAG signals, we applied a novel classifier fusion system based on the dynamic weighted fusion (DWF) method to ameliorate the classification performance. For comparison, a single leastsquares support vector machine (LS-SVM) and the Bagging ensemble were used for the classification task as well. The results in terms of overall accuracy in percentage and area under the receiver operating characteristic curve obtained with the DWF-based classifier fusion method reached 88.76% and 0.9515, respectively, which demonstrated the effectiveness and superiority of the DWF method with two distinct features for the VAG signal analysis. PMID:23573175

Extreme ultraviolet explorer satellite observation of Jupiter's Io plasma torus

NASA Technical Reports Server (NTRS)

Hall, D. T; Gladstone, G. R.; Moos, H. W.; Bagenal, F.; Clarke, J. T.; Feldman, P. D.; Mcgrath, M. A.; Schneider, N. M.; Shemansky, D. E.; Strobel, D. F.

1994-01-01

We present the first Extreme Ultraviolet Explorer (EUVE) satellite observation of the Jupiter system, obtained during the 2 day period 1993 March 30 through April 1, which shows a rich emission-line spectrum from the Io plasma torus spanning wavelengths 370 to 735 A. The emission features correspond primarily to known multiplets of oxygen and sulfur ions, but a blended feature near 372 A is a plausible Na II transition. The summed detected energy flux of (7.2 +/- 0.2) x 10(exp -11) ergs/sq cm(s) corresponds to a radiated power of approximately equal to 4 x 10(exp 11) W in this spectral range. All ansa emissions show a distinct dawn-dusk brightness asymmetry and the measured dusk/dawn ratio of the bright S III lambda-680 feature is 2.3 +/- 0.3, significantly larger than the ratio measured by the Voyager spacecraft ultraviolet (UV) instruments. A preliminary estimate of ion partitioning indicates that the oxygen/sulfur ion ratio is approximately equal to 2, compared to the value approximately equal to 1.3 measured by Voyager, and that (Na(+))/(e) greater than 0.01.

Detecting apoptosis in vivo and ex vivo using spectroscopic OCT and dynamic light scattering

NASA Astrophysics Data System (ADS)

Farhat, Golnaz; Giles, Anoja; Mariampillai, Adrian; Yang, Victor X. D.; Czarnota, Gregory J.; Kolios, Michael C.

2014-03-01

We present an in vivo implementation of a multi-parametric technique for detecting apoptosis using optical coherence tomography in a mouse tumor model. Solid tumors were grown from acute myeloid leukemia cells in the hind leg of SCID mice and treated with a single dose of cisplatin and dexamethasone to induce apoptosis. Both spectral features and speckle decorrelation times indicated good consistency between control mice and reasonable agreement with in vitro measurements. The integrated backscatter increased significantly in tumors responding to treatment while the spectral slope and decorrelation time did not show significant changes. This study demonstrates the feasibility of using spectroscopic OCT and dynamic light scattering for treatment monitoring in vivo.

The Flowfield Characteristics of a Mach 2 Diamond Jet

NASA Technical Reports Server (NTRS)

Washington, Donnell; Alvi, Farrukh S.; Krothapalli, Anjanevulu

1997-01-01

The potential for using a novel diamond-shaped nozzle which may allow for superior mixing characteristics of supersonic jets without significant thrust losses is explored. The results of flow visualization and pressure measurements indicate the presence of distinct structures in the shear layers, not normally observed in shear layers of axisymmetric and rectangular jets. As characteristics of these features suggests that they are a manifestation of significant streamwise vorticity in the shear layers. Despite the distinct nature of the flowfield structure of the present shear layer, the global growth rates of this shear layer were found to be very similar to its two-dimensional and axisymmetric counterparts. These and other observations suggest that the presence of streamwise vorticity may not play a significant role in the global development of a compressible shear layer.

Uncoupling of Secretion From Growth in Some Hormone Secretory Tissues

PubMed Central

2014-01-01

Context: Most syndromes with benign primary excess of a hormone show positive coupling of hormone secretion to size or proliferation in the affected hormone secretory tissue. Syndromes that lack this coupling seem rare and have not been examined for unifying features among each other. Evidence Acquisition: Selected clinical and basic features were analyzed from original reports and reviews. We examined indices of excess secretion of a hormone and indices of size of secretory tissue within the following three syndromes, each suggestive of uncoupling between these two indices: familial hypocalciuric hypercalcemia, congenital diazoxide-resistant hyperinsulinism, and congenital primary hyperaldosteronism type III (with G151E mutation of the KCNJ5 gene). Evidence Synthesis: Some unifying features among the three syndromes were different from features present among common tumors secreting the same hormone. The unifying and distinguishing features included: 1) expression of hormone excess as early as the first days of life; 2) normal size of tissue that oversecretes a hormone; 3) diffuse histologic expression in the hormonal tissue; 4) resistance to treatment by subtotal ablation of the hormone-secreting tissue; 5) causation by a germline mutation; 6) low potential of the same mutation to cause a tumor by somatic mutation; and 7) expression of the mutated molecule in a pathway between sensing of a serum metabolite and secretion of hormone regulating that metabolite. Conclusion: Some shared clinical and basic features of uncoupling of secretion from size in a hormonal tissue characterize three uncommon states of hormone excess. These features differ importantly from features of common hormonal neoplasm of that tissue. PMID:25004249

Generation of Kappa Distributions in Solar Wind at 1 au

NASA Astrophysics Data System (ADS)

Livadiotis, G.; Desai, M. I.; Wilson, L. B., III

2018-02-01

We examine the generation of kappa distributions in the solar wind plasma near 1 au. Several mechanisms are mentioned in the literature, each characterized by a specific relationship between the solar wind plasma features, the interplanetary magnetic field (IMF), and the kappa index—the parameter that governs the kappa distributions. This relationship serves as a signature condition that helps the identification of the mechanism in the plasma. In general, a mechanism that generates kappa distributions involves a single or a series of stochastic or physical processes that induces local correlations among particles. We identify three fundamental solar wind plasma conditions that can generate kappa distributions, noted as (i) Debye shielding, (ii) frozen IMF, and (iii) temperature fluctuations, each one prevailing in different scales of solar wind plasma and magnetic field properties. Moreover, our findings show that the kappa distributions, and thus, their generating mechanisms, vary significantly with solar wind features: (i) the kappa index has different dependence on the solar wind speed for slow and fast modes, i.e., slow wind is characterized by a quasi-constant kappa index, κ ≈ 4.3 ± 0.7, while fast wind exhibits kappa indices that increase with bulk speed; (ii) the dispersion of magnetosonic waves is more effective for lower kappa indices (i.e., further from thermal equilibrium); and (iii) the kappa and polytropic indices are positively correlated, as it was anticipated by the theory.

Vesta Mineralogy after Dawn Global Observations

NASA Technical Reports Server (NTRS)

ChristinaDeSanctis, Maria; Ammannito, E.; Capaccioni, F.; Cparia, M. T.; Carraro, F.; Fonte, S.; Frigeri, A.; Longobardo, A.; Marchi, S.; Palomba, E.;

A problematic early tetrapod from the Mississippian of Nevada

USGS Publications Warehouse

Thomson, K.S.; Shubin, N.S.; Poole, F.G.

1998-01-01

We report here the discovery of a new taxon of Paleozoic tetrapod from the Late Mississippian of Nevada (330-340 Ma). It has a unique vertebral column with principal centra having vertical anterior and posterior faces, ventrally incomplete accessory centra located antero-dorsally in each centrum, and enlarged presacral/sacral vertebrae. The head and pectoral girdle were not preserved but the large femur, robust pelvic girdle and enlarged sacral vertebrae possibly indicate a terrestrial mode of life. This new form significantly extends the western geographic range of known Mississippian tetrapods. It presents a mosaic of primitive and derived features, indicating that continued revision of traditional accounts of vertebral homology and the early diversifications of Paleozoic tetrapods will be necessary.

Intrahepatic cholangiocarcinoma prognostic determination using pre-operative serum C-reactive protein levels.

PubMed

Lin, Zi-Ying; Liang, Zhen-Xing; Zhuang, Pei-Lin; Chen, Jie-Wei; Cao, Yun; Yan, Li-Xu; Yun, Jing-Ping; Xie, Dan; Cai, Mu-Yan

2016-10-12

Serum C-reactive protein (CRP), an acute inflammatory response biomarker, has been recognized as an indicator of malignant disease progression. However, the prognostic significance of CRP levels collected before tumor removal in intrahepatic cholangiocarcinoma requires further investigation. We sampled the CRP levels in 140 patients with intrahepatic cholangiocarcinoma who underwent hepatectomies with regional lymphadenectomies between 2006 and 2013. A retrospective analysis of the clinicopathological data was performed. We focused on the impact of serum CRP on the patients' cancer-specific survival and recurrence-free survival rates. High levels of preoperative serum CRP were significantly associated with well-established clinicopathologic features, including gender, advanced tumor stage, and elevated carcinoembryonic antigen and carbohydrate antigen 19-9 levels (P < 0.05). Univariate analysis demonstrated a significant association between high levels of serum CRP and adverse cancer-specific survival (P = 0.001) and recurrence-free survival (P < 0.001). In patients with stage I/II intrahepatic cholangiocarcinoma, the serum CRP level was a prognostic indicator for cancer-specific survival. In patients with stage I/II or stage III/IV, the serum CRP level was a prognostic indicator for recurrence-free survival (P < 0.05). Additionally, multivariate analysis identified serum CRP level in intrahepatic cholangiocarcinoma as an independent prognostic factor (P < 0.05). We confirmed a significant association of elevated pre-operative CRP levels with poor clinical outcomes for the tested patients with intrahepatic cholangiocarcinoma. Our results indicate that the serum CRP level may represent a useful factor for patient stratification in intrahepatic cholangiocarcinoma management.

Ultrahigh-Resolution 3-Dimensional Seismic Imaging of Seeps from the Continental Slope of the Northern Gulf of Mexico: Subsurface, Seafloor and Into the Water Column

NASA Astrophysics Data System (ADS)

Brookshire, B. N., Jr.; Mattox, B. A.; Parish, A. E.; Burks, A. G.

2016-02-01

Utilizing recently advanced ultrahigh-resolution 3-dimensional (UHR3D) seismic tools we have imaged the seafloor geomorphology and associated subsurface aspects of seep related expulsion features along the continental slope of the northern Gulf of Mexico with unprecedented clarity and continuity. Over an area of approximately 400 km2, over 50 discrete features were identified and three general seafloor geomorphologies indicative of seep activity including mounds, depressions and bathymetrically complex features were quantitatively characterized. Moreover, areas of high seafloor reflectivity indicative of mineralization and areas of coherent seismic amplitude anomalies in the near-seafloor water column indicative of active gas expulsion were identified. In association with these features, shallow source gas accumulations and migration pathways based on salt related stratigraphic uplift and faulting were imaged. Shallow, bottom simulating reflectors (BSRs) interpreted to be free gas trapped under near seafloor gas hydrate accumulations were very clearly imaged.

Cosmetics as a feature of the extended human phenotype: modulation of the perception of biologically important facial signals.

PubMed

Etcoff, Nancy L; Stock, Shannon; Haley, Lauren E; Vickery, Sarah A; House, David M

2011-01-01

Research on the perception of faces has focused on the size, shape, and configuration of inherited features or the biological phenotype, and largely ignored the effects of adornment, or the extended phenotype. Research on the evolution of signaling has shown that animals frequently alter visual features, including color cues, to attract, intimidate or protect themselves from conspecifics. Humans engage in conscious manipulation of visual signals using cultural tools in real time rather than genetic changes over evolutionary time. Here, we investigate one tool, the use of color cosmetics. In two studies, we asked viewers to rate the same female faces with or without color cosmetics, and we varied the style of makeup from minimal (natural), to moderate (professional), to dramatic (glamorous). Each look provided increasing luminance contrast between the facial features and surrounding skin. Faces were shown for 250 ms or for unlimited inspection time, and subjects rated them for attractiveness, competence, likeability and trustworthiness. At 250 ms, cosmetics had significant positive effects on all outcomes. Length of inspection time did not change the effect for competence or attractiveness. However, with longer inspection time, the effect of cosmetics on likability and trust varied by specific makeup looks, indicating that cosmetics could impact automatic and deliberative judgments differently. The results suggest that cosmetics can create supernormal facial stimuli, and that one way they may do so is by exaggerating cues to sexual dimorphism. Our results provide evidence that judgments of facial trustworthiness and attractiveness are at least partially separable, that beauty has a significant positive effect on judgment of competence, a universal dimension of social cognition, but has a more nuanced effect on the other universal dimension of social warmth, and that the extended phenotype significantly influences perception of biologically important signals at first glance and at longer inspection.

Cosmetics as a Feature of the Extended Human Phenotype: Modulation of the Perception of Biologically Important Facial Signals

PubMed Central

Etcoff, Nancy L.; Stock, Shannon; Haley, Lauren E.; Vickery, Sarah A.; House, David M.

2011-01-01

Research on the perception of faces has focused on the size, shape, and configuration of inherited features or the biological phenotype, and largely ignored the effects of adornment, or the extended phenotype. Research on the evolution of signaling has shown that animals frequently alter visual features, including color cues, to attract, intimidate or protect themselves from conspecifics. Humans engage in conscious manipulation of visual signals using cultural tools in real time rather than genetic changes over evolutionary time. Here, we investigate one tool, the use of color cosmetics. In two studies, we asked viewers to rate the same female faces with or without color cosmetics, and we varied the style of makeup from minimal (natural), to moderate (professional), to dramatic (glamorous). Each look provided increasing luminance contrast between the facial features and surrounding skin. Faces were shown for 250 ms or for unlimited inspection time, and subjects rated them for attractiveness, competence, likeability and trustworthiness. At 250 ms, cosmetics had significant positive effects on all outcomes. Length of inspection time did not change the effect for competence or attractiveness. However, with longer inspection time, the effect of cosmetics on likability and trust varied by specific makeup looks, indicating that cosmetics could impact automatic and deliberative judgments differently. The results suggest that cosmetics can create supernormal facial stimuli, and that one way they may do so is by exaggerating cues to sexual dimorphism. Our results provide evidence that judgments of facial trustworthiness and attractiveness are at least partially separable, that beauty has a significant positive effect on judgment of competence, a universal dimension of social cognition, but has a more nuanced effect on the other universal dimension of social warmth, and that the extended phenotype significantly influences perception of biologically important signals at first glance and at longer inspection. PMID:21991328

Comparison between users of a new methodology for heart sound auscultation.

PubMed

Castro, Ana; Gomes, Pedro; Mattos, Sandra S; Coimbra, Miguel T

2016-08-01

Auscultation is a routine exam and the first line of screening in heart pathologies. The objective of this study was to assess if using a new data collection system, the DigiScope Collector, with a guided and automatic annotation of heart auscultation, different levels of expertise/experience users could collect similar digital auscultations. Data were collected within the Heart Caravan Initiative (Paraíba, Brasil). Patients were divided into two study groups: Group 1 evaluated by a third year medical student (User 1), and an experienced nurse (User 2); Group 2 evaluated by User 2 and an Information Technology professional (User 3). Patients were auscultated sequentially by the two users, according to the randomization. Features extracted from each data set included the length (HR) of the audio files, the number of repetitions per auscultation area, heart rate, first (S1) and second (S2) heart sound amplitudes, S2/S1, and aortic (A2) and pulmonary (P2) components of the second heart sound and relative amplitudes (P2/A2). Features extracted were compared between users using paired-sample test Wilcoxon test, and Spearman correlations (P<;0.05 considered significant). Twenty-seven patients were included in the study (13 Group 1, and 14 Group 2). No statistical significant differences were found between groups, except in the time of auscultation (User 2 consistently presented longer auscultation time). Correlation analysis showed significant correlations between extracted features from both groups: S2/S1 in Group 1, and S1, S2, A2, P2, P2/A2 amplitudes, and HR in Group 2. Using the DigiScope Collector, we were able to collect similar digital auscultations, according to the features evaluated. This may indicate that in sites with limited access to specialized clinical care, auscultation files may be acquired and used in telemedicine for an expert evaluation.

An Analysis of Activities in Saudi Arabian Middle School Science Textbooks and Workbooks for the Inclusion of Essential Features of Inquiry

ERIC Educational Resources Information Center

Aldahmash, Abdulwali H.; Mansour, Nasser S.; Alshamrani, Saeed M.; Almohi, Saeed

2016-01-01

This study examines Saudi Arabian middle school science textbooks' coverage of the essential features of scientific inquiry. All activities in the middle school science textbooks and workbooks were analyzed by using the scientific inquiry "essential features" rubric. The results indicated that the essential features are included in about…

The relationship between antisocial and borderline features and aggression in young adult men in treatment for substance use disorders

PubMed Central

Shorey, Ryan C.; Elmquist, Joanna; Anderson, Scott; Stuart, Gregory L.

2016-01-01

There is a large literature documenting that adult men in treatment for substance use disorders perpetrate more aggression than men without substance use disorders. Unfortunately, there is minimal research on aggression among young adult men (i.e., 18–25 years of age) in treatment for substance use. Moreover, although aggression is more likely to occur when individuals are acutely intoxicated by alcohol or drugs, research also suggests that antisocial (ASPD) and borderline (BPD) personality features increase the chances an individual will use aggression. The current study therefore examined the associations between ASPD and BPD features, including specific features that are reflective of impulsivity, and aggression in young adult men in treatment for substance use disorders (N = 79). Controlling for age, education, alcohol and drug use, ASPD features were positively associated with various indicators of aggression (e.g., physical, verbal, attitudinal), whereas BPD features were only associated with physical aggression. However, ASPD and BPD features that were specific to impulsivity were robustly related to indicators of aggression. Findings suggest that substance use treatment should attempt to target ASPD and BPD features in young adult men, which may help reduce aggression after treatment. PMID:26941068

Soil features and indoor radon concentration prediction: radon in soil gas, pedology, permeability and 226Ra content.

PubMed

Lara, E; Rocha, Z; Santos, T O; Rios, F J; Oliveira, A H

2015-11-01

This work aims at relating some physicochemical features of soils and their use as a tool for prediction of indoor radon concentrations of the Metropolitan Region of Belo Horizonte (RMBH), Minas Gerais, Brazil. The measurements of soil gas radon concentrations were performed by using an AlphaGUARD monitor. The (226)Ra content analysis was performed by gamma spectrometry (high pure germanium) and permeabilities were performed by using the RADON-JOK permeameter. The GEORP indicator and soil radon index (RI) were also calculated. Approximately 53 % of the Perferric Red Latosols measurement site could be classified as 'high risk' (Swedish criteria). The Litholic Neosols presented the lowest radon concentration mean in soil gas. The Perferric Red Latosols presented significantly high radon concentration mean in soil gas (60.6 ± 8.7 kBq m(-3)), high indoor radon concentration, high RI, (226)Ra content and GEORP. The preliminary results may indicate an influence of iron formations present very close to the Perferric Red Latosols in the retention of uranium minerals. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

A hybrid computational approach for efficient Alzheimer's disease classification based on heterogeneous data.

PubMed

Ding, Xuemei; Bucholc, Magda; Wang, Haiying; Glass, David H; Wang, Hui; Clarke, Dave H; Bjourson, Anthony John; Dowey, Le Roy C; O'Kane, Maurice; Prasad, Girijesh; Maguire, Liam; Wong-Lin, KongFatt

2018-06-27

There is currently a lack of an efficient, objective and systemic approach towards the classification of Alzheimer's disease (AD), due to its complex etiology and pathogenesis. As AD is inherently dynamic, it is also not clear how the relationships among AD indicators vary over time. To address these issues, we propose a hybrid computational approach for AD classification and evaluate it on the heterogeneous longitudinal AIBL dataset. Specifically, using clinical dementia rating as an index of AD severity, the most important indicators (mini-mental state examination, logical memory recall, grey matter and cerebrospinal volumes from MRI and active voxels from PiB-PET brain scans, ApoE, and age) can be automatically identified from parallel data mining algorithms. In this work, Bayesian network modelling across different time points is used to identify and visualize time-varying relationships among the significant features, and importantly, in an efficient way using only coarse-grained data. Crucially, our approach suggests key data features and their appropriate combinations that are relevant for AD severity classification with high accuracy. Overall, our study provides insights into AD developments and demonstrates the potential of our approach in supporting efficient AD diagnosis.

Glaciotectonic deformation associated with the Orient Point-Fishers Island moraine, westernmost Block Island Sound: further evidence of readvance of the Laurentide ice sheet

USGS Publications Warehouse

Poppe, Lawrence J.; Oldale, Robert N.; Foster, David S.; Smith, Shepard M.

2012-01-01

High-resolution seismic-reflection profiles collected across pro-glacial outwash deposits adjacent to the circa 18 ka b.p. Orient Point–Fishers Island end moraine segment in westernmost Block Island Sound reveal extensive deformation. A rhythmic seismic facies indicates the host outwash deposits are composed of fine-grained glaciolacustrine sediments. The deformation is variably brittle and ductile, but predominantly compressive in nature. Brittle deformation includes reverse faults and thrust faults that strike parallel to the moraine, and thrust sheets that extend from beneath the moraine. Ductile deformation includes folded sediments that overlie undisturbed deposits, showing that they are not drape features. Other seismic evidence for compression along the ice front consists of undisturbed glaciolacustrine strata that dip back toward and underneath the moraine, and angular unconformities on the sea floor where deformed sediments extend above the surrounding undisturbed correlative strata. Together, these ice-marginal glaciotectonic features indicate that the Orient Point–Fishers Island moraine marks a significant readvance of the Laurentide ice sheet, consistent with existing knowledge for neighboring coeval moraines, and not simply a stillstand as previously reported.

Believing in paranormal phenomena: relations to asymmetry of body and brain.

PubMed

Schulter, Günter; Papousek, Ilona

2008-01-01

The goal of this study was to investigate the possible relationship between established measures of body and brain asymmetries and individual differences in paranormal beliefs. In addition to behavioural measures of cerebral laterality, measures of facial features and finger length were taken to calculate body asymmetry scores and indicators of fluctuating asymmetry (average absolute differences between left and right body features). Both the direction and degree of laterality measures were used. In addition to that, quantitative measures of inconsistency of cerebral lateralization were obtained. Results indicated that a stronger belief in paranormal phenomena was associated with fluctuating asymmetry of finger length, and that this aspect of body asymmetry may be related to greater intraindividual variability in the degree of 'atypical' functional lateralization. This intraindividual variability index, in turn, significantly predicted strength of belief in the paranormal. Belief in the paranormal was also higher in women than men and it was negatively correlated with the education level. In sum, these findings suggest that a part of the variance of strength of belief in paranormal phenomena can be explained by patterns of functional hemispheric asymmetry that may be related to perturbations during fetal development.

Detection and localization of damage using empirical mode decomposition and multilevel support vector machine

NASA Astrophysics Data System (ADS)

Dushyanth, N. D.; Suma, M. N.; Latte, Mrityanjaya V.

2016-03-01

Damage in the structure may raise a significant amount of maintenance cost and serious safety problems. Hence detection of the damage at its early stage is of prime importance. The main contribution pursued in this investigation is to propose a generic optimal methodology to improve the accuracy of positioning of the flaw in a structure. This novel approach involves a two-step process. The first step essentially aims at extracting the damage-sensitive features from the received signal, and these extracted features are often termed the damage index or damage indices, serving as an indicator to know whether the damage is present or not. In particular, a multilevel SVM (support vector machine) plays a vital role in the distinction of faulty and healthy structures. Formerly, when a structure is unveiled as a damaged structure, in the subsequent step, the position of the damage is identified using Hilbert-Huang transform. The proposed algorithm has been evaluated in both simulation and experimental tests on a 6061 aluminum plate with dimensions 300 mm × 300 mm × 5 mm which accordingly yield considerable improvement in the accuracy of estimating the position of the flaw.

Annoyance from industrial noise: indicators for a wide variety of industrial sources.

PubMed

Alayrac, M; Marquis-Favre, C; Viollon, S; Morel, J; Le Nost, G

2010-09-01

In the study of noises generated by industrial sources, one issue is the variety of industrial noise sources and consequently the complexity of noises generated. Therefore, characterizing the environmental impact of an industrial plant requires better understanding of the noise annoyance caused by industrial noise sources. To deal with the variety of industrial sources, the proposed approach is set up by type of spectral features and based on a perceptive typology of steady and permanent industrial noises comprising six categories. For each perceptive category, listening tests based on acoustical factors are performed on noise annoyance. Various indicators are necessary to predict noise annoyance due to various industrial noise sources. Depending on the spectral features of the industrial noise sources, noise annoyance indicators are thus assessed. In case of industrial noise sources without main spectral features such as broadband noise, noise annoyance is predicted by the A-weighted sound pressure level L(Aeq) or the loudness level L(N). For industrial noises with spectral components such as low-frequency noises with a main component at 100 Hz or noises with spectral components in middle frequencies, indicators are proposed here that allow good prediction of noise annoyance by taking into account spectral features.

Spectroscopic Diagnosis of Arsenic Contamination in Agricultural Soils

PubMed Central

Shi, Tiezhu; Liu, Huizeng; Chen, Yiyun; Fei, Teng; Wang, Junjie; Wu, Guofeng

2017-01-01

This study investigated the abilities of pre-processing, feature selection and machine-learning methods for the spectroscopic diagnosis of soil arsenic contamination. The spectral data were pre-processed by using Savitzky-Golay smoothing, first and second derivatives, multiplicative scatter correction, standard normal variate, and mean centering. Principle component analysis (PCA) and the RELIEF algorithm were used to extract spectral features. Machine-learning methods, including random forests (RF), artificial neural network (ANN), radial basis function- and linear function- based support vector machine (RBF- and LF-SVM) were employed for establishing diagnosis models. The model accuracies were evaluated and compared by using overall accuracies (OAs). The statistical significance of the difference between models was evaluated by using McNemar’s test (Z value). The results showed that the OAs varied with the different combinations of pre-processing, feature selection, and classification methods. Feature selection methods could improve the modeling efficiencies and diagnosis accuracies, and RELIEF often outperformed PCA. The optimal models established by RF (OA = 86%), ANN (OA = 89%), RBF- (OA = 89%) and LF-SVM (OA = 87%) had no statistical difference in diagnosis accuracies (Z < 1.96, p < 0.05). These results indicated that it was feasible to diagnose soil arsenic contamination using reflectance spectroscopy. The appropriate combination of multivariate methods was important to improve diagnosis accuracies. PMID:28471412

Landslide inventory for the Little North Santiam River Basin, Oregon

USGS Publications Warehouse

Sobieszczyk, Steven

2010-01-01

This geodatabase is an inventory of existing landslides in the Little North Santiam River Basin, Oregon (2009). Each landslide feature shown has been classified according to a number of specific characteristics identified at the time recorded in the GIS database. The classification scheme was developed by the Oregon Department of Geology and Mineral Industries (Burns and Madin, 2009). Several significant landslide characteristics recorded in the database are portrayed with symbology on this map. The specific characteristics shown for each landslide are the activity of landsliding, landslide features, deep or shallow failure, type of landslide movement, and confidence of landslide interpretation. These landslide characteristics are determined primarily on the basis of geomorphic features, or landforms, observed for each landslide. This work was completed as part of the Master's thesis "Turbidity Monitoring and LiDAR Imagery Indicate Landslides are Primary Source of Suspended-Sediment Load in the Little North Santiam River Basin, Oregon, Winter 2009-2010" by Steven Sobieszczyk, Portland State University and U.S. Geological Survey. Data layers in this geodatabase include: landslide deposit boundaries (Deposits); field-verfied location imagery (Photos); head scarp or scarp flanks (Scarp_Flanks); and secondary scarp features (Scarps).The geodatabase template was developed by the Oregon Department of Geology and Mineral Industries (Burns and Madin, 2009).

Characteristics of Mild Cognitive Impairment Using the Thai Version of the Consortium to Establish a Registry for Alzheimer's Disease Tests: A Multivariate and Machine Learning Study.

PubMed

Tunvirachaisakul, Chavit; Supasitthumrong, Thitiporn; Tangwongchai, Sookjareon; Hemrunroj, Solaphat; Chuchuen, Phenphichcha; Tawankanjanachot, Itthipol; Likitchareon, Yuthachai; Phanthumchinda, Kamman; Sriswasdi, Sira; Maes, Michael

2018-04-04

The Consortium to Establish a Registry for Alzheimer's Disease (CERAD) developed a neuropsychological battery (CERAD-NP) to screen patients with Alzheimer's dementia. Mild cognitive impairment (MCI) has received attention as a pre-dementia stage. To delineate the CERAD-NP features of MCI and their clinical utility to externally validate MCI diagnosis. The study included 60 patients with MCI, diagnosed using the Clinical Dementia Rating, and 63 normal controls. Data were analysed employing receiver operating characteristic analysis, Linear Support Vector Machine, Random Forest, Adaptive Boosting, Neural Network models, and t-distributed stochastic neighbour embedding (t-SNE). MCI patients were best discriminated from normal controls using a combination of Wordlist Recall, Wordlist Memory, and Verbal Fluency Test. Machine learning showed that the CERAD features learned from MCI patients and controls were not strongly predictive of the diagnosis (maximal cross-validation 77.2%), whilst t-SNE showed that there is a considerable overlap between MCI and controls. The most important features of the CERAD-NP differentiating MCI from normal controls indicate impairments in episodic and semantic memory and recall. While these features significantly discriminate MCI patients from normal controls, the tests are not predictive of MCI. © 2018 S. Karger AG, Basel.

Estimation of age of Dali-Ganis rifting and associated volcanic activity, Venus

NASA Technical Reports Server (NTRS)

Basilevsky, A. T.

1993-01-01

This paper deals with the estimation of age for the Dali and Ganis Chasma rift zones and their associated volcanism based on photogeologic analysis of stratigraphic relations of rift-associated features with impact craters which have associated features indicative of their age. The features are radar-dark and parabolic, and they are believed to be mantles of debris derived from fallout of the craters' ejecta. They are thought to be among the youngest features on the Venusian surface, so their 'parent' craters must also be very young, evidently among the youngest 10 percent of Venus' crater population. Dali Chasma and Ganis Chasma are a part of a system of rift zones contained within eastern Aphrodite and Atla Regio which is a significant component of Venus tectonics. The rifts of this system are fracture belts which dissect typical Venusian plains with rare islands of tessera terrain. The rift zone system consists of several segments following each other (Diane, Dali, Ganis) and forming the major rift zone line, about 10,000 km long, which has junctions with several other rift zones, including Parga Chasma Rift. The junctions are usually locations of rift-associated volcanism in the form of volcanic edifices (Maat and Ozza Montes) or plain-forming flows flooding some areas within the rift zones and the adjacent plains.

An Analysis of Activities in Saudi Arabian Middle School Science Textbooks and Workbooks for the Inclusion of Essential Features of Inquiry

NASA Astrophysics Data System (ADS)

Aldahmash, Abdulwali H.; Mansour, Nasser S.; Alshamrani, Saeed M.; Almohi, Saeed

2016-12-01

This study examines Saudi Arabian middle school science textbooks' coverage of the essential features of scientific inquiry. All activities in the middle school science textbooks and workbooks were analyzed by using the scientific inquiry `essential features' rubric. The results indicated that the essential features are included in about 59 % of the analyzed science activities. However, feature 2, `making learner give priority to evidence in responding to questions' and feature 3, `allowing learner to formulate explanations from evidence' appeared more frequently than the other three features (feature 1: engaging learner in scientifically oriented questions, feature 4: helping learner connect explanations to scientific knowledge, and feature 5: helping learner communicate and justify explanations to others), whether in the activities as a whole, or in the activities included in each of the four science domains (physical science, Earth science, life science and chemistry). These features are represented in almost all activities. This means that almost all activities in the middle school science textbooks and the workbooks include features 2 and 3. Meanwhile, the mean level of inclusion of the five essential features of scientific inquiry found in the middle school science textbooks and workbooks as a whole is 2.55. However, results found for features 1, 4, 5 and for in-level inclusion of the inquiry features in each of the science domains indicate that the inclusion of the essential inquiry features is teacher-centred. As a result, neither science textbooks nor workbooks provide students with the opportunity or encouragement to develop their inquiry skills. Consequently, the results suggest important directions for educational administrators and policy-makers in the preparation and use of science educational content.

Feature Selection Using Information Gain for Improved Structural-Based Alert Correlation

PubMed Central

Siraj, Maheyzah Md; Zainal, Anazida; Elshoush, Huwaida Tagelsir; Elhaj, Fatin

2016-01-01

Grouping and clustering alerts for intrusion detection based on the similarity of features is referred to as structurally base alert correlation and can discover a list of attack steps. Previous researchers selected different features and data sources manually based on their knowledge and experience, which lead to the less accurate identification of attack steps and inconsistent performance of clustering accuracy. Furthermore, the existing alert correlation systems deal with a huge amount of data that contains null values, incomplete information, and irrelevant features causing the analysis of the alerts to be tedious, time-consuming and error-prone. Therefore, this paper focuses on selecting accurate and significant features of alerts that are appropriate to represent the attack steps, thus, enhancing the structural-based alert correlation model. A two-tier feature selection method is proposed to obtain the significant features. The first tier aims at ranking the subset of features based on high information gain entropy in decreasing order. The‏ second tier extends additional features with a better discriminative ability than the initially ranked features. Performance analysis results show the significance of the selected features in terms of the clustering accuracy using 2000 DARPA intrusion detection scenario-specific dataset. PMID:27893821

Using erosion associated with glaciovolcanic features to document the existence of pre-LGM ice-sheets: examples from the Kawdy Plateau, northern British Columbia

NASA Astrophysics Data System (ADS)

Dunnington, Gwen; Edwards, Benjamin R.; Ryane, Chanone; Russell, James K.; Lasher, Gregory K.

2010-05-01

One of the most significant difficulties with understanding terrestrial Pleistocene climate change is that the depositional record of ancient ice sheets is frequently destroyed by successive glaciations. Given their resistance to erosion, glaciovolcanic features provide unique opportunities at which to look for evidence of multiple glaciations. Evidence from the Kawdy Plateau (KP) region of northern British Columbia is consistent with the presence of multiple ice sheets covering the Canadian Cordillera over the past 2 Ma and derives from two sources: features interpreted as having formed by glacial scouring of bedrock, and the state of preservation for six glaciovolcanic edifices (Kawdy Mountain, Tutsingale Mountain, Nuthinaw Mountain, Meehaz Mountain, Tanker tuya, Horseshoe tuya) located on the plateau. Detailed measurements of glacial mega-grooves/striations on bedrock in the eastern part of the plateau, along with similar features on two different edifices (Tutsingale Mountain and Tanker tuya), are consistent with ice movement in three distinctly different azimuths: 21-59 degrees; 60-88 degrees; 88-92 degrees. The scours may indicate the presence of at least three separate glaciers flowing in different directions over the KP, separated by enough time to allow the previous glacier to melt entirely and expose the plateau floor to continued erosion. Cross-cutting relationships and quality of preservation indicate that the group trending between 88-92° across the plateau and tuyas is the oldest, the group trending 21-59° is younger than that, and a group trending 60-88° is the youngest, presumably related to ice flow during the Last Glacial Maximum (LGM). Drumlinoid features on the plateau floor and on top of Horseshoe Tuya indicate that despite this 71° variation in orientation direction of scours across the entire area, the general direction of ice movement across the plateau has always been in an east-to-west or northeast-to-southwest direction. The states of erosion for all six of the KP glaciovolcanic edifices are consistent with extensive glaciation. Besides the glacial features noted above, at least three of the edifices (Kawdy Mountain, Tanker tuya, Horseshoe tuya) show evidence for extensive morphological modification. Although the core of Kawdy Mountain is made of erosion-resistant palagonitized volcanic breccia and intrusions, its core has been eviscerated and now has a long, northeasterly trending cirque-like valley. Horseshoe tuya appears to have lost almost half of its original volume into a north-facing, cirque-like feature. The aerial footprint of Tanker tuya is consistent with erosion of more than half of the original edifice, and its lower stratigraphy may contain at least one pre-LGM glacial diamicton. We believe that these observations indicate that the Cordilleran Ice Sheet (CIS) did not remain constant and intact during the Pleistocene, but fluctuated between periods of thick, low-elevation ice cover and more sparse, high-elevation cover. Evidence for multi-stage continental glaciation has important implications for the reconstruction of the history of the Cordilleran ice sheet, correlation with the marine Pleistocene climate record, and constraints on the paleoclimate factors which influenced terrestrial ice sheet development.

Time irreversibility and intrinsics revealing of series with complex network approach

NASA Astrophysics Data System (ADS)

Xiong, Hui; Shang, Pengjian; Xia, Jianan; Wang, Jing

2018-06-01

In this work, we analyze time series on the basis of the visibility graph algorithm that maps the original series into a graph. By taking into account the all-round information carried by the signals, the time irreversibility and fractal behavior of series are evaluated from a complex network perspective, and considered signals are further classified from different aspects. The reliability of the proposed analysis is supported by numerical simulations on synthesized uncorrelated random noise, short-term correlated chaotic systems and long-term correlated fractal processes, and by the empirical analysis on daily closing prices of eleven worldwide stock indices. Obtained results suggest that finite size has a significant effect on the evaluation, and that there might be no direct relation between the time irreversibility and long-range correlation of series. Similarity and dissimilarity between stock indices are also indicated from respective regional and global perspectives, showing the existence of multiple features of underlying systems.

Copernicus observations of Ly-alpha and Mg II emission from HR 1099 /V711 Tauri/ and UX Ari

NASA Technical Reports Server (NTRS)

Weiler, E. J.

1978-01-01

Ultraviolet observations of two RS CVn binaries obtained with Copernicus are described. High-resolution (0.05 A) U1 observations indicate that both HR 1099 and UX Ari display broad Ly-alpha emission. The Ly-alpha emission strength from HR 1099 is variable and seems to be correlated with orbital phase, while the UX Ari results indicate no significant variation. Moderate resolution (0.51 A) V2 scans of both systems show variable Mg II h and k emission-line profiles which usually matched the velocity of the more active star in each binary. Additionally, displaced emission components were seen at velocities of up to + or - 250 km/s, indicative of high-velocity gas motions. The radial velocities of these emission features from HR 1099 are marginally correlated with orbital phase. Highly active and variable chromospheric phenomena are found to be the most consistent explanation of these results.

Adaptation to suspensory locomotion in Australopithecus sediba.

PubMed

Rein, Thomas R; Harrison, Terry; Carlson, Kristian J; Harvati, Katerina

2017-03-01

Australopithecus sediba is represented by well-preserved fossilized remains from the locality of Malapa, South Africa. Recent work has shown that the combination of features in the limb skeleton of A. sediba was distinct from that of earlier species of Australopithecus, perhaps indicating that this species moved differently. The bones of the arm and forearm indicate that A. sediba was adapted to suspensory and climbing behaviors. We used a geometric morphometric approach to examine ulnar shape, potentially identifying adaptations to forelimb suspensory locomotion in A. sediba. Results indicated suspensory capabilities in this species and a stronger forelimb suspensory signal than has been documented in Australopithecus afarensis. Our study confirms the adaptive significance of functional morphological traits for arboreal movements in the locomotor repertoire of A. sediba and provides important insight into the diversity and mosaic nature of locomotor adaptations among early hominins. Copyright © 2017 Elsevier Ltd. All rights reserved.

F*** Yeah Fluid Dynamics: Lessons from online outreach

NASA Astrophysics Data System (ADS)

Sharp, Nicole

2013-11-01

The fluid dynamics education outreach blog FYFD features photos, videos, and research along with concise, accessible explanations of phenomena every weekday. Over the past three years, the blog has attracted an audience of roughly 200,000 online followers. Reader survey results indicate that over half of the blog's audience works or studies in non-fluids fields. Twenty-nine percent of all survey respondents indicate that FYFD has been a positive influence on their desire to pursue fluid dynamics in their education or career. Of these positively influenced readers, over two-thirds have high-school or undergraduate-level education, indicating a significant audience of potential future fluid dynamicists. This talk will utilize a mixture of reader metrics, web analytics, and anecdotal evidence to discuss what makes science outreach successful and how we, as a community, can benefit from promoting fluid dynamics to a wider audience. http://tinyurl.com/azjjgj2

Inherited Fe and Ti electron transition spectroscopic features in altered ultramafic-carbonatite intrusives

NASA Astrophysics Data System (ADS)

Shavers, E. J.; Ghulam, A.; Encarnacion, J. P.

2016-12-01

Spectroscopic reflectance in the visible to short-wave infrared region is an important tool for remote geologic mapping and is applied at scales from satellite to field measurements. Remote geologic mapping is challenging in regions subject to significant surficial weathering. Here we identify absorption features found in altered volcanic pipes and dikes in the Avon Volcanic District, Missouri, that are inherited from the original ultramafic and carbonatite lithology. Alteration ranges from small degree hydrothermal alteration to extensive laterization. The absorption features are three broad minima centered near 690, 890, and 1100 nm. Features in this region are recognized to be caused by ferric and ferrous Fe minerals including olivine, carbonates, chlorite, and goethite all of which are found among the Avon pipes and dikes that are in various stages of alteration. Iron-related intervalence charge transfer and crystal field perturbations of ions are the principal causes of the spectroscopic features in the visible to near-infrared region yet spectra are also distorted by factors like texture and the presence of opaque minerals known to reduce overall reflectance. In the Avon samples, Fe oxide content can reach >15 wt% leading to prominent absorption features even in the less altered ultramafics with reflectance curve maxima as low as 5%. The exaggerated minima allow the altered intrusive rocks to stand out among other weathered lithologies that will often have clay features in the region yet have lower iron concentration. The absorption feature centered near 690 nm is particularly noteworthy. Broad mineral-related absorption features centered at this wavelength are rare but have been linked to Ti3+ in octahedral coordination. The reduced form of Ti is not common in surface lithologies. Titanium-rich andradite has Ti3+ in the octahedral position, is resistant to weathering, is found among the Avon lithologies including ultramafic, carbonatite, and carbonated breccia, and is identified here as the cause of the 690 nm absorption feature. The Ti3+ absorption feature centered near 690 nm and strong Fe absorption features at 890 and 1100 nm may be useful indicators of rare intrusive lithologies in remote geologic mapping.

Structural MRI-based detection of Alzheimer's disease using feature ranking and classification error.

PubMed

Beheshti, Iman; Demirel, Hasan; Farokhian, Farnaz; Yang, Chunlan; Matsuda, Hiroshi

2016-12-01

This paper presents an automatic computer-aided diagnosis (CAD) system based on feature ranking for detection of Alzheimer's disease (AD) using structural magnetic resonance imaging (sMRI) data. The proposed CAD system is composed of four systematic stages. First, global and local differences in the gray matter (GM) of AD patients compared to the GM of healthy controls (HCs) are analyzed using a voxel-based morphometry technique. The aim is to identify significant local differences in the volume of GM as volumes of interests (VOIs). Second, the voxel intensity values of the VOIs are extracted as raw features. Third, the raw features are ranked using a seven-feature ranking method, namely, statistical dependency (SD), mutual information (MI), information gain (IG), Pearson's correlation coefficient (PCC), t-test score (TS), Fisher's criterion (FC), and the Gini index (GI). The features with higher scores are more discriminative. To determine the number of top features, the estimated classification error based on training set made up of the AD and HC groups is calculated, with the vector size that minimized this error selected as the top discriminative feature. Fourth, the classification is performed using a support vector machine (SVM). In addition, a data fusion approach among feature ranking methods is introduced to improve the classification performance. The proposed method is evaluated using a data-set from ADNI (130 AD and 130 HC) with 10-fold cross-validation. The classification accuracy of the proposed automatic system for the diagnosis of AD is up to 92.48% using the sMRI data. An automatic CAD system for the classification of AD based on feature-ranking method and classification errors is proposed. In this regard, seven-feature ranking methods (i.e., SD, MI, IG, PCC, TS, FC, and GI) are evaluated. The optimal size of top discriminative features is determined by the classification error estimation in the training phase. The experimental results indicate that the performance of the proposed system is comparative to that of state-of-the-art classification models. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Mining the key predictors for event outbreaks in social networks

NASA Astrophysics Data System (ADS)

Yi, Chengqi; Bao, Yuanyuan; Xue, Yibo

2016-04-01

It will be beneficial to devise a method to predict a so-called event outbreak. Existing works mainly focus on exploring effective methods for improving the accuracy of predictions, while ignoring the underlying causes: What makes event go viral? What factors that significantly influence the prediction of an event outbreak in social networks? In this paper, we proposed a novel definition for an event outbreak, taking into account the structural changes to a network during the propagation of content. In addition, we investigated features that were sensitive to predicting an event outbreak. In order to investigate the universality of these features at different stages of an event, we split the entire lifecycle of an event into 20 equal segments according to the proportion of the propagation time. We extracted 44 features, including features related to content, users, structure, and time, from each segment of the event. Based on these features, we proposed a prediction method using supervised classification algorithms to predict event outbreaks. Experimental results indicate that, as time goes by, our method is highly accurate, with a precision rate ranging from 79% to 97% and a recall rate ranging from 74% to 97%. In addition, after applying a feature-selection algorithm, the top five selected features can considerably improve the accuracy of the prediction. Data-driven experimental results show that the entropy of the eigenvector centrality, the entropy of the PageRank, the standard deviation of the betweenness centrality, the proportion of re-shares without content, and the average path length are the key predictors for an event outbreak. Our findings are especially useful for further exploring the intrinsic characteristics of outbreak prediction.

Characterization of coronary plaque regions in intravascular ultrasound images using a hybrid ensemble classifier.

PubMed

Hwang, Yoo Na; Lee, Ju Hwan; Kim, Ga Young; Shin, Eun Seok; Kim, Sung Min

2018-01-01

The purpose of this study was to propose a hybrid ensemble classifier to characterize coronary plaque regions in intravascular ultrasound (IVUS) images. Pixels were allocated to one of four tissues (fibrous tissue (FT), fibro-fatty tissue (FFT), necrotic core (NC), and dense calcium (DC)) through processes of border segmentation, feature extraction, feature selection, and classification. Grayscale IVUS images and their corresponding virtual histology images were acquired from 11 patients with known or suspected coronary artery disease using 20 MHz catheter. A total of 102 hybrid textural features including first order statistics (FOS), gray level co-occurrence matrix (GLCM), extended gray level run-length matrix (GLRLM), Laws, local binary pattern (LBP), intensity, and discrete wavelet features (DWF) were extracted from IVUS images. To select optimal feature sets, genetic algorithm was implemented. A hybrid ensemble classifier based on histogram and texture information was then used for plaque characterization in this study. The optimal feature set was used as input of this ensemble classifier. After tissue characterization, parameters including sensitivity, specificity, and accuracy were calculated to validate the proposed approach. A ten-fold cross validation approach was used to determine the statistical significance of the proposed method. Our experimental results showed that the proposed method had reliable performance for tissue characterization in IVUS images. The hybrid ensemble classification method outperformed other existing methods by achieving characterization accuracy of 81% for FFT and 75% for NC. In addition, this study showed that Laws features (SSV and SAV) were key indicators for coronary tissue characterization. The proposed method had high clinical applicability for image-based tissue characterization. Copyright © 2017 Elsevier B.V. All rights reserved.

The Reconstruction and Failure Analysis of The Space Shuttle Columbia

NASA Technical Reports Server (NTRS)

Russell, Richard W.

2010-01-01

This viewgraph presentation describes a very detailed reconstruction plan and failure analysis of The Space Shuttle Columbia accident. The contents include: 1) STS-107 Timeline; 2) Foam Impact; 3) Recovery; 4) Reconstruction; 5) Reconstruction Plan; 6) Reconstruction Hanger; 7) Pathfinders; 8) Aluminum Pathfinder; 9) Early Analysis - Left MLG Door Area; 10) Emphasis Switched to Left Hand Wing Leading Edge; 11) Wing Leading Edge Subsystem (LESS); 12) 3D Reconstruction of Left WLE; 13) Left Wing Tile Table; 14) LESS Observations; 15) Left Hand Wing Debris Points to RCC 8/9 - Slumped Tile; 16) Reconstructed View of LC/P 9 tile with I/B Tile; 17) Reconstructed View of Lower C/P 9 Tile; 18) Carrier Panel 8 - Upper; 19) Left Hand Wing Debris Points to RCC 8/9 - Erosion and RCC with attach hole intact; 20) Erosion on Panel 8 Upper Outboard Rib; 21) RCC Panels 8 & 9 Erosion Features; 22) Slumping Source for Carrier Panel 9 Tile was Revealed; 23) Debris Indicated Highest Probability Initiation Site; 24) Left Hand Wing Debris Points to RCC 8/9- Metallic Deposits; 25) Relative Metallic Deposition on L/H Wing Materials; 26) Metallic Deposit Example, LH RCC 8; 27) High Level Questions; 28) Analysis Plan Challenges; 29) Analysis Techniques; 30) Analysis Approach; 31) RCC Panel 8 Erosion Features; 32) Radiographic Features; 33) Radiography WLE LH Panel 8; 34) LH RCC 8 Upper Apex; 35) LH RCC 8 - Deposit Feature: Thick Tear Shaped; 36) LH RCC 8 - Deposit Feature: Thick Globules; 37) LH RCC 8 - Deposit Feature: Spheroids; 38) LH RCC 8 - Deposit Feature: Uniform Deposit; 39) Significant Findings - Sampling All Other panels; 40) Proposed Breach Location and Plasma Flow; 41) Corroborating Information - RCC Panel Debris Locations; 42) Corroborating Information - LH OMS Pod Analysis; 43) Corroborating Information - Impact Testing; and 44) Overall Forensic Conclusions.

Observations of hysteresis in solar cycle variations among seven solar activity indicators

NASA Technical Reports Server (NTRS)

Bachmann, Kurt T.; White, Oran R.

1994-01-01

We show that smoothed time series of 7 indices of solar activity exhibit significant solar cycle dependent differences in their relative variations during the past 20 years. In some cases these observed hysteresis patterns start to repeat over more than one solar cycle, giving evidence that this is a normal feature of solar variability. Among the indices we study, we find that the hysteresis effects are approximately simple phase shifts, and we quantify these phase shifts in terms of lag times behind the leading index, the International Sunspot Number. Our measured lag times range from less than one month to greater than four months and can be much larger than lag times estimated from short-term variations of these same activity indices during the emergence and decay of major active regions. We argue that hysteresis represents a real delay in the onset and decline of solar activity and is an important clue in the search for physical processes responsible for changing solar emission at various wavelengths.

Handwriting features of children with developmental coordination disorder--results of triangular evaluation.

PubMed

Rosenblum, Sara; Margieh, Jumana Aassy; Engel-Yeger, Batya

2013-11-01

Developmental coordination disorders (DCD) is one of the most common disorders affecting school-aged children. The study aimed to characterize the handwriting performance of children with DCD who write in Arabic, based on triangular evaluation. Participants included 58 children aged 11-12 years, 29 diagnosed with DCD based on the DSM-IV criteria and the M-ABC, and 29 matched typically developed controls. Children were asked to copy a paragraph on a sheet of paper affixed to a digitizer supplying objective measures of the handwriting process. The handwriting proficiency screening questionnaire (HPSQ) was completed by their teachers while observing their performance and followed by evaluation of their final written product. Results indicated that compared to controls, children with DCD required significantly more on-paper and in-air time per stroke while copying. In addition, global legibility, unrecognizable letters and spatial arrangement measures of their written product were significantly inferior. Significant group differences were also found between the HPSQ subscales scores. Furthermore, 82.8% of all participants were correctly classified into groups based on one discriminate function which included two handwriting performance measures. These study results strongly propose application of triangular standardized evaluation to receive better insight of handwriting deficit features of individual children with DCD who write in Arabic. Copyright © 2013 Elsevier Ltd. All rights reserved.

MR image analytics to characterize upper airway architecture in children with OSAS

NASA Astrophysics Data System (ADS)

Tong, Yubing; Udupa, Jayaram K.; Torigian, Drew A.; Matsumoto, Monica M. S.; Sin, Sanghun; Arens, Raanan

2015-03-01

Mechanisms leading to Obstructive Sleep Apnea Syndrome (OSAS) in obese children are not well understood. We previously analyzed polysomnographic and demographic data to study the anatomical characteristics of the upper airway and body composition in two groups of obese children with and without OSAS, where object volume was evaluated. In this paper, in order to better understand the disease we expand the analysis considering a variety of features that include object-specific features such as size, surface area, sphericity, and image intensity properties of fourteen objects in the vicinity of the upper airway, as well as inter-object relationships such as distance between objects. Our preliminary results indicate several interesting phenomena: volumes and surface areas of adenoid and tonsils increase statistically significantly in OSAS. Standardized T2-weighted MR image intensities differ statistically significantly between the two groups, implying that perhaps intrinsic tissue composition undergoes changes in OSAS. Inter-object distances are significantly different between the two groups for object pairs (skin, oropharynx), (skin, fat pad), (skin, soft palate), (mandible, tongue), (oropharynx, soft palate), (left tonsil, oropharynx), (left tonsil, fat pad) and (left tonsil, right tonsil). We conclude that treatment methods for OSAS such as adenotonsillectomy should respect proportional object size relationships and spatial arrangement of objects as they exist in control subjects.

A comparative intelligibility study of single-microphone noise reduction algorithms.

PubMed

Hu, Yi; Loizou, Philipos C

2007-09-01

The evaluation of intelligibility of noise reduction algorithms is reported. IEEE sentences and consonants were corrupted by four types of noise including babble, car, street and train at two signal-to-noise ratio levels (0 and 5 dB), and then processed by eight speech enhancement methods encompassing four classes of algorithms: spectral subtractive, sub-space, statistical model based and Wiener-type algorithms. The enhanced speech was presented to normal-hearing listeners for identification. With the exception of a single noise condition, no algorithm produced significant improvements in speech intelligibility. Information transmission analysis of the consonant confusion matrices indicated that no algorithm improved significantly the place feature score, significantly, which is critically important for speech recognition. The algorithms which were found in previous studies to perform the best in terms of overall quality, were not the same algorithms that performed the best in terms of speech intelligibility. The subspace algorithm, for instance, was previously found to perform the worst in terms of overall quality, but performed well in the present study in terms of preserving speech intelligibility. Overall, the analysis of consonant confusion matrices suggests that in order for noise reduction algorithms to improve speech intelligibility, they need to improve the place and manner feature scores.

Association between Organizational Commitment and Personality Traits of Faculty Members of Ahvaz Jundishapur University of Medical Sciences.

PubMed

Khiavi, Farzad Faraji; Dashti, Rezvan; Mokhtari, Saeedeh

2016-03-01

Individual characteristics are important factors influencing organizational commitment. Also, committed human resources can lead organizations to performance improvement as well as personal and organizational achievements. This research aimed to determine the association between organizational commitment and personality traits among faculty members of Ahvaz Jundishapur University of Medical Sciences. the research population of this cross-sectional study was the faculty members of Ahvaz Jundishapur University of Medical Sciences (Ahvaz, Iran). The sample size was determined to be 83. Data collection instruments were the Allen and Meyer questionnaire for organizational commitment and Neo for characteristics' features. The data were analyzed through Pearson's product-moment correlation and the independent samples t-test, ANOVA, and simple linear regression analysis (SLR) by SPSS. Continuance commitment showed a significant positive association with neuroticism, extroversion, agreeableness, and conscientiousness. Normative commitment showed a significant positive association with conscientiousness and a negative association with extroversion (p = 0.001). Openness had a positive association with affective commitment. Openness and agreeableness, among the five characteristics' features, had the most effect on organizational commitment, as indicated by simple linear regression analysis. Faculty members' characteristics showed a significant association with their organizational commitment. Determining appropriate characteristic criteria for faculty members may lead to employing committed personnel to accomplish the University's objectives and tasks.

Improving robustness against electrode shift of high density EMG for myoelectric control through common spatial patterns.

PubMed

Pan, Lizhi; Zhang, Dingguo; Jiang, Ning; Sheng, Xinjun; Zhu, Xiangyang

2015-12-02

Most prosthetic myoelectric control studies have concentrated on low density (less than 16 electrodes, LD) electromyography (EMG) signals, due to its better clinical applicability and low computation complexity compared with high density (more than 16 electrodes, HD) EMG signals. Since HD EMG electrodes have been developed more conveniently to wear with respect to the previous versions recently, HD EMG signals become an alternative for myoelectric prostheses. The electrode shift, which may occur during repositioning or donning/doffing of the prosthetic socket, is one of the main reasons for degradation in classification accuracy (CA). HD EMG signals acquired from the forearm of the subjects were used for pattern recognition-based myoelectric control in this study. Multiclass common spatial patterns (CSP) with two types of schemes, namely one versus one (CSP-OvO) and one versus rest (CSP-OvR), were used for feature extraction to improve the robustness against electrode shift for myoelectric control. Shift transversal (ST1 and ST2) and longitudinal (SL1 and SL2) to the direction of the muscle fibers were taken into consideration. We tested nine intact-limb subjects for eleven hand and wrist motions. The CSP features (CSP-OvO and CSP-OvR) were compared with three commonly used features, namely time-domain (TD) features, time-domain autoregressive (TDAR) features and variogram (Variog) features. Compared with the TD features, the CSP features significantly improved the CA over 10 % in all shift configurations (ST1, ST2, SL1 and SL2). Compared with the TDAR features, a. the CSP-OvO feature significantly improved the average CA over 5 % in all shift configurations; b. the CSP-OvR feature significantly improved the average CA in shift configurations ST1, SL1 and SL2. Compared with the Variog features, the CSP features significantly improved the average CA in longitudinal shift configurations (SL1 and SL2). The results demonstrated that the CSP features significantly improved the robustness against electrode shift for myoelectric control with respect to the commonly used features.

Linear indices of the "molecular pseudograph's atom adjacency matrix": definition, significance-interpretation, and application to QSAR analysis of flavone derivatives as HIV-1 integrase inhibitors.

PubMed

Marrero-Ponce, Yovani

2004-01-01

This report describes a new set of molecular descriptors of relevance to QSAR/QSPR studies and drug design, atom linear indices fk(xi). These atomic level chemical descriptors are based on the calculation of linear maps on Rn[fk(xi): Rn--> Rn] in canonical basis. In this context, the kth power of the molecular pseudograph's atom adjacency matrix [Mk(G)] denotes the matrix of fk(xi) with respect to the canonical basis. In addition, a local-fragment (atom-type) formalism was developed. The kth atom-type linear indices are calculated by summing the kth atom linear indices of all atoms of the same atom type in the molecules. Moreover, total (whole-molecule) linear indices are also proposed. This descriptor is a linear functional (linear form) on Rn. That is, the kth total linear indices is a linear map from Rn to the scalar R[ fk(x): Rn --> R]. Thus, the kth total linear indices are calculated by summing the atom linear indices of all atoms in the molecule. The features of the kth total and local linear indices are illustrated by examples of various types of molecular structures, including chain-lengthening, branching, heteroatoms-content, and multiple bonds. Additionally, the linear independence of the local linear indices to other 0D, 1D, 2D, and 3D molecular descriptors is demonstrated by using principal component analysis for 42 very heterogeneous molecules. Much redundancy and overlapping was found among total linear indices and most of the other structural indices presently in use in the QSPR/QSAR practice. On the contrary, the information carried by atom-type linear indices was strikingly different from that codified in most of the 229 0D-3D molecular descriptors used in this study. It is concluded that the local linear indices are an independent indices containing important structural information to be used in QSPR/QSAR and drug design studies. In this sense, atom, atom-type, and total linear indices were used for the prediction of pIC50 values for the cleavage process of a set of flavone derivatives inhibitors of HIV-1 integrase. Quantitative models found are significant from a statistical point of view (R of 0.965, 0.902, and 0.927, respectively) and permit a clear interpretation of the studied properties in terms of the structural features of molecules. A LOO cross-validation procedure revealed that the regression models had a fairly good predictability (q2 of 0.679, 0.543, and 0.721, respectively). The comparison with other approaches reveals good behavior of the method proposed. The approach described in this paper appears to be an excellent alternative or guides for discovery and optimization of new lead compounds.

Associations Between PET Textural Features and GLUT1 Expression, and the Prognostic Significance of Textural Features in Lung Adenocarcinoma.

PubMed

Koh, Young Wha; Park, Seong Yong; Hyun, Seung Hyup; Lee, Su Jin

2018-02-01

We evaluated the association between positron emission tomography (PET) textural features and glucose transporter 1 (GLUT1) expression level and further investigated the prognostic significance of textural features in lung adenocarcinoma. We evaluated 105 adenocarcinoma patients. We extracted texture-based PET parameters of primary tumors. Conventional PET parameters were also measured. The relationships between PET parameters and GLUT1 expression levels were evaluated. The association between PET parameters and overall survival (OS) was assessed using Cox's proportional hazard regression models. In terms of PET textural features, tumors expressing high levels of GLUT1 exhibited significantly lower coarseness, contrast, complexity, and strength, but significantly higher busyness. On univariate analysis, the metabolic tumor volume, total lesion glycolysis, contrast, busyness, complexity, and strength were significant predictors of OS. Multivariate analysis showed that lower complexity (HR=2.017, 95%CI=1.032-3.942, p=0.040) was independently associated with poorer survival. PET textural features may aid risk stratification in lung adenocarcinoma patients. Copyright© 2018, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

Plant phenolics and absorption features in vegetation reflectance spectra near 1.66 μm

NASA Astrophysics Data System (ADS)

Kokaly, Raymond F.; Skidmore, Andrew K.

2015-12-01

Past laboratory and field studies have quantified phenolic substances in vegetative matter from reflectance measurements for understanding plant response to herbivores and insect predation. Past remote sensing studies on phenolics have evaluated crop quality and vegetation patterns caused by bedrock geology and associated variations in soil geochemistry. We examined spectra of pure phenolic compounds, common plant biochemical constituents, dry leaves, fresh leaves, and plant canopies for direct evidence of absorption features attributable to plant phenolics. Using spectral feature analysis with continuum removal, we observed that a narrow feature at 1.66 μm is persistent in spectra of manzanita, sumac, red maple, sugar maple, tea, and other species. This feature was consistent with absorption caused by aromatic Csbnd H bonds in the chemical structure of phenolic compounds and non-hydroxylated aromatics. Because of overlapping absorption by water, the feature was weaker in fresh leaf and canopy spectra compared to dry leaf measurements. Simple linear regressions of feature depth and feature area with polyphenol concentration in tea resulted in high correlations and low errors (% phenol by dry weight) at the dry leaf (r2 = 0.95, RMSE = 1.0%, n = 56), fresh leaf (r2 = 0.79, RMSE = 2.1%, n = 56), and canopy (r2 = 0.78, RMSE = 1.0%, n = 13) levels of measurement. Spectra of leaves, needles, and canopies of big sagebrush and evergreens exhibited a weak absorption feature centered near 1.63 μm, short ward of the phenolic compounds, possibly consistent with terpenes. This study demonstrates that subtle variation in vegetation spectra in the shortwave infrared can directly indicate biochemical constituents and be used to quantify them. Phenolics are of lesser abundance compared to the major plant constituents but, nonetheless, have important plant functions and ecological significance. Additional research is needed to advance our understanding of the spectral influences of plant phenolics and terpenes relative to dominant leaf biochemistry (water, chlorophyll, protein/nitrogen, cellulose, and lignin).

Predicting Future Morphological Changes of Lesions from Radiotracer Uptake in 18F-FDG-PET Images

PubMed Central

Bagci, Ulas; Yao, Jianhua; Miller-Jaster, Kirsten; Chen, Xinjian; Mollura, Daniel J.

2013-01-01

We introduce a novel computational framework to enable automated identification of texture and shape features of lesions on 18F-FDG-PET images through a graph-based image segmentation method. The proposed framework predicts future morphological changes of lesions with high accuracy. The presented methodology has several benefits over conventional qualitative and semi-quantitative methods, due to its fully quantitative nature and high accuracy in each step of (i) detection, (ii) segmentation, and (iii) feature extraction. To evaluate our proposed computational framework, thirty patients received 2 18F-FDG-PET scans (60 scans total), at two different time points. Metastatic papillary renal cell carcinoma, cerebellar hemongioblastoma, non-small cell lung cancer, neurofibroma, lymphomatoid granulomatosis, lung neoplasm, neuroendocrine tumor, soft tissue thoracic mass, nonnecrotizing granulomatous inflammation, renal cell carcinoma with papillary and cystic features, diffuse large B-cell lymphoma, metastatic alveolar soft part sarcoma, and small cell lung cancer were included in this analysis. The radiotracer accumulation in patients' scans was automatically detected and segmented by the proposed segmentation algorithm. Delineated regions were used to extract shape and textural features, with the proposed adaptive feature extraction framework, as well as standardized uptake values (SUV) of uptake regions, to conduct a broad quantitative analysis. Evaluation of segmentation results indicates that our proposed segmentation algorithm has a mean dice similarity coefficient of 85.75±1.75%. We found that 28 of 68 extracted imaging features were correlated well with SUVmax (p<0.05), and some of the textural features (such as entropy and maximum probability) were superior in predicting morphological changes of radiotracer uptake regions longitudinally, compared to single intensity feature such as SUVmax. We also found that integrating textural features with SUV measurements significantly improves the prediction accuracy of morphological changes (Spearman correlation coefficient = 0.8715, p<2e-16). PMID:23431398

Features of color reflection in psychogenic pain in patients with somatoform disorders during psychotherapeutic treatment.

PubMed

Ishinova, Vera A; Svyatogor, Irina A; Reznikova, Tatiana N

2009-11-01

The present work examines the change in color reflection in psychogenic pain in patients with somatoform disorders (SFD) during psychotherapeutic treatment, for which empatho-techniques were used. At the start and end of the course the psychophysiological condition was determined according to psychological parameters and assessment of bioelectrical brain activity. All initial indicators for the patients significantly differed from those for the healthy subjects. At the same time, color reflection in the psychogenic pain was characterised by colors in the longwave part of the spectrum, in contradistinction to healthy subjects for whom achromatic and shortwave colors predominated. After the completed course patients with SFD had a significant improvement of all psychophysiological indicators and a lack of color reflectons in the longwave part of the spectrum. The data obtained permits the proposition that there exists a link between the psychogenic pain, its color reflection and anxiety, and also changes in the functional condition of the CNS.

Pulse oximeter plethysmographic waveform changes in awake, spontaneously breathing, hypovolemic volunteers.

PubMed

McGrath, Susan P; Ryan, Kathy L; Wendelken, Suzanne M; Rickards, Caroline A; Convertino, Victor A

2011-02-01

The primary objective of this study was to determine whether alterations in the pulse oximeter waveform characteristics would track progressive reductions in central blood volume. We also assessed whether changes in the pulse oximeter waveform provide an indication of blood loss in the hemorrhaging patient before changes in standard vital signs. Pulse oximeter data from finger, forehead, and ear pulse oximeter sensors were collected from 18 healthy subjects undergoing progressive reduction in central blood volume induced by lower body negative pressure (LBNP). Stroke volume measurements were simultaneously recorded using impedance cardiography. The study was conducted in a research laboratory setting where no interventions were performed. Pulse amplitude, width, and area under the curve (AUC) features were calculated from each pulse wave recording. Amalgamated correlation coefficients were calculated to determine the relationship between the changes in pulse oximeter waveform features and changes in stroke volume with LBNP. For pulse oximeter sensors on the ear and forehead, reductions in pulse amplitude, width, and area were strongly correlated with progressive reductions in stroke volume during LBNP (R(2) ≥ 0.59 for all features). Changes in pulse oximeter waveform features were observed before profound decreases in arterial blood pressure. The best correlations between pulse features and stroke volume were obtained from the forehead sensor area (R(2) = 0.97). Pulse oximeter waveform features returned to baseline levels when central blood volume was restored. These results support the use of pulse oximeter waveform analysis as a potential diagnostic tool to detect clinically significant hypovolemia before the onset of cardiovascular decompensation in spontaneously breathing patients.

SigFlux: a novel network feature to evaluate the importance of proteins in signal transduction networks.

PubMed

Liu, Wei; Li, Dong; Zhang, Jiyang; Zhu, Yunping; He, Fuchu

2006-11-27

Measuring each protein's importance in signaling networks helps to identify the crucial proteins in a cellular process, find the fragile portion of the biology system and further assist for disease therapy. However, there are relatively few methods to evaluate the importance of proteins in signaling networks. We developed a novel network feature to evaluate the importance of proteins in signal transduction networks, that we call SigFlux, based on the concept of minimal path sets (MPSs). An MPS is a minimal set of nodes that can perform the signal propagation from ligands to target genes or feedback loops. We define SigFlux as the number of MPSs in which each protein is involved. We applied this network feature to the large signal transduction network in the hippocampal CA1 neuron of mice. Significant correlations were simultaneously observed between SigFlux and both the essentiality and evolutionary rate of genes. Compared with another commonly used network feature, connectivity, SigFlux has similar or better ability as connectivity to reflect a protein's essentiality. Further classification according to protein function demonstrates that high SigFlux, low connectivity proteins are abundant in receptors and transcriptional factors, indicating that SigFlux candescribe the importance of proteins within the context of the entire network. SigFlux is a useful network feature in signal transduction networks that allows the prediction of the essentiality and conservation of proteins. With this novel network feature, proteins that participate in more pathways or feedback loops within a signaling network are proved far more likely to be essential and conserved during evolution than their counterparts.

Desired features of smartphone applications promoting physical activity.

PubMed

Rabin, Carolyn; Bock, Beth

2011-12-01

Approximately one-third of adults in the United States are physically inactive. This is a significant public health concern as physical activity (PA) can influence the risk of cardiovascular disease, diabetes, and certain forms of cancer. To minimize these health risks, effective PA interventions must be developed and disseminated to the vast number of individuals who remain sedentary. Smartphone technology presents an exciting opportunity for delivering PA interventions remotely. Although a number of PA applications are currently available for smartphones, these "apps" are not based on established theories of health behavior change and most do not include evidence-based features (e.g., reinforcement and goal setting). Our aim was to collect formative data to develop a smartphone PA app that is empirically and theoretically-based and incorporates user preferences. We recruited 15 sedentary adults to test three currently available PA smartphone apps and provide qualitative and quantitative feedback. Findings indicate that users have a number of specific preferences with regard to PA app features, including that apps provide automatic tracking of PA (e.g., steps taken and calories burned), track progress toward PA goals, and integrate a music feature. Participants also preferred that PA apps be flexible enough to be used with several types of PA, and have well-documented features and user-friendly interfaces (e.g., a one-click main page). When queried by the researcher, most participants endorsed including goal-setting and problem-solving features. These findings provide a blue print for developing a smartphone PA app that incorporates evidence-based components and user preferences.

Major depressive disorder with psychotic features may lead to misdiagnosis of dementia: a case report and review of the literature.

PubMed

Wagner, Gerhardt S; McClintock, Shawn M; Rosenquist, Peter B; McCall, W Vaughn; Kahn, David A

2011-11-01

Major depressive disorder (MDD) with psychotic features is relatively frequent in patients with greater depressive symptom severity and is associated with a poorer course of illness and greater functional impairment than MDD without psychotic features. Multiple studies have found that patients with psychotic mood disorders demonstrate significantly poorer cognitive performance in a variety of areas than those with nonpsychotic mood disorders. The Mini Mental State Examination (MMSE) and the Dementia Rating Scale, Second Edition (DRS-2) are widely used to measure cognitive functions in research on MDD with psychotic features. Established total raw score cut-offs of 24 on the MMSE and 137 on the DRS-2 in published manuals suggest possible global cognitive impairment and dementia, respectively. Limited research is available on these suggested cut-offs for patients with MDD with psychotic features. We document the therapeutic benefit of electroconvulsive therapy (ECT), which is usually associated with short-term cognitive impairment, in a 68-year-old woman with psychotic depression whose MMSE and DRS-2 scores initially suggested possible global cognitive impairment and dementia. Over the course of four ECT treatments, the patient's MMSE scores progressively increased. After the second ECT treatment, the patient no longer met criteria for global cognitive impairment. With each treatment, depression severity, measured by the 24-item Hamilton Rating Scale for Depression, improved sequentially. Thus, the suggested cut-off scores for the MMSE and the DRS-2 in patients with MDD with psychotic features may in some cases produce false-positive indications of dementia.

Exploration of EEG features of Alzheimer's disease using continuous wavelet transform.

PubMed

Ghorbanian, Parham; Devilbiss, David M; Hess, Terry; Bernstein, Allan; Simon, Adam J; Ashrafiuon, Hashem

2015-09-01

We have developed a novel approach to elucidate several discriminating EEG features of Alzheimer's disease. The approach is based on the use of a variety of continuous wavelet transforms, pairwise statistical tests with multiple comparison correction, and several decision tree algorithms, in order to choose the most prominent EEG features from a single sensor. A pilot study was conducted to record EEG signals from Alzheimer's disease (AD) patients and healthy age-matched control (CTL) subjects using a single dry electrode device during several eyes-closed (EC) and eyes-open (EO) resting conditions. We computed the power spectrum distribution properties and wavelet and sample entropy of the wavelet coefficients time series at scale ranges approximately corresponding to the major brain frequency bands. A predictive index was developed using the results from statistical tests and decision tree algorithms to identify the most reliable significant features of the AD patients when compared to healthy controls. The three most dominant features were identified as larger absolute mean power and larger standard deviation of the wavelet scales corresponding to 4-8 Hz (θ) during EO and lower wavelet entropy of the wavelet scales corresponding to 8-12 Hz (α) during EC, respectively. The fourth reliable set of distinguishing features of AD patients was lower relative power of the wavelet scales corresponding to 12-30 Hz (β) followed by lower skewness of the wavelet scales corresponding to 2-4 Hz (upper δ), both during EO. In general, the results indicate slowing and lower complexity of EEG signal in AD patients using a very easy-to-use and convenient single dry electrode device.

Validity and reliability of the attention deficit hyperactivity disorder self-report scale (ASRS-v1.1) in a clinical sample with eating disorders.

PubMed

Carlucci, Samantha; Ivanova, Iryna; Bissada, Hany; Tasca, Giorgio A

2017-08-01

Individuals with eating disorders (EDs) commonly experience comorbid attention deficit hyperactivity disorder (ADHD). The shared features of EDs and ADHD, such as inattention, impulsivity and hyperactivity, may exacerbate ED symptomatology and pose challenges to treatment. It is important to screen patients with EDs for symptoms of ADHD to optimize their treatment outcomes. However, the psychometrics of common measures of ADHD have not yet been examined within an ED population. An example of such a measure is the ADHD self-report scale (ASRS-v1.1) symptom checklist, which identifies the presence of ADHD symptoms. This study reports a psychometric study of the ASRS-v1.1 in a clinical sample of 500 adults with an ED. A confirmatory factor analysis indicated the ASRS-v1.1 maintained its two-factor structure of inattention and impulsivity/hyperactivity. The item loadings demonstrated path invariance across ED diagnostic groups indicating construct validity. Further, the subscales exhibited good internal consistency and they were significantly correlated with other measures of impulsivity indicating convergent validity. The ED sample had significantly higher mean scores than published nonclinical norms indicating predictive validity, but the ASRS-v1.1 scores were not significantly different among ED diagnostic groups. Results suggest the ASRS-v1.1 is a valid and reliable screening tool for identifying symptoms of ADHD among adults seeking treatment for ED. Copyright © 2017 Elsevier Ltd. All rights reserved.