Nonchronological Video Synopsis and Indexing Pritch, Y.; Rav-Acha, A.; Peleg, S.
IEEE transactions on pattern analysis and machine intelligence,
11/2008, Volume:
30, Issue:
11
Journal Article
Peer reviewed
The amount of captured video is growing with the increased numbers of video cameras, especially the increase of millions of surveillance cameras that operate 24 hours a day. Since video browsing and ...retrieval is time consuming, most captured video is never watched or examined. Video synopsis is an effective tool for browsing and indexing of such a video. It provides a short video representation, while preserving the essential activities of the original video. The activity in the video is condensed into a shorter period by simultaneously showing multiple activities, even when they originally occurred at different times. The synopsis video is also an index into the original video by pointing to the original time of each activity. Video synopsis can be applied to create a synopsis of an endless video streams, as generated by Webcams and by surveillance cameras. It can address queries like "show in one minute the synopsis of this camera broadcast during the past day''. This process includes two major phases: (i) an online conversion of the endless video stream into a database of objects and activities (rather than frames). (ii) A response phase, generating the video synopsis as a response to the user's query.
Spectral Matting Levin, A.; Rav Acha, A.; Lischinski, D.
IEEE transactions on pattern analysis and machine intelligence,
10/2008, Volume:
30, Issue:
10
Journal Article
Peer reviewed
We present spectral matting: a new approach to natural image matting that automatically computes a basis set of fuzzy matting components from the smallest eigenvectors of a suitably defined Laplacian ...matrix. Thus, our approach extends spectral segmentation techniques, whose goal is to extract hard segments, to the extraction of soft matting components. These components may then be used as building blocks to easily construct semantically meaningful foreground mattes, either in an unsupervised fashion, or based on a small amount of user input.
Motion blur is a smearing of the image due to a long aperture time. We show that when two motion-blurred images are available, having different blur directions, image restoration can be improved ...substantially. In particular, the direction of the motion blur and the PSF (Point Spread Function) of the blur can be computed robustly.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Objective
To assess the prevalence of the frailty syndrome and its associated variables among the older adult population in the province of Toledo (Spain).
Methods
Data were taken from the Toledo ...Study for Healthy Aging, a population-based study conducted on 2,488 individuals aged 65 years and older. Study participants were selected by a two-stage random sampling from the municipal census of Toledo, covering both institutionalized and community dwelling persons from rural and urban settings. Data were collected from 2006 to 2009, and included information on social support, activities of daily living, comorbidity, physical activity, quality of life, depressive symptoms, and cognitive function. In addition, a nurse collected anthropometric data, conducted tests of physical performance (walk speed, upper and lower extremities strength, and the stand-and-sit from a chair test) and obtained a blood sample. The diagnosis of the frailty syndrome was based on the Fried criteria (weakness, low speed, low physical activity, exhaustion, and weight loss).
Results
In total, 41.8% (95% confidence interval CI 39.4–44.2%) of the study participants were prefrail, and 8.4% (95% CI 7.1–9.8%) were frail. There were no differences in the prevalence of frailty by sex, level of education, occupation, marital status, or place of residence. The frequency of the frailty syndrome increased with age, and was higher in those with disability, depression, hip fracture and other comorbidity, such as cardiovascular disease and disorders of the central nervous system.
Conclusions
The prevalence of the frailty syndrome in older Spanish adults is high and similar to that reported in other populations in the Mediterranean basin.
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EMUNI, GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UILJ, UL, UM, UPCLJ, UPUK, VSZLJ, ZAGLJ, ZRSKP
Degradation of the mechanical properties of vinylester and epoxy matrix composites exposed to water has been approached by monitoring the strengths of glass and carbon fibers and resins. In addition, ...the fiber/matrix (F/M) interface strengths and debond lengths of single-fiber composites were determined and test results were compared to test results of macroscopic composite specimens. The single-fiber tensile test results indicate a substantial loss of the tensile strength of glass fibers and the fragmentation tests reveal loss of F/M shear strength and substantial debonding for both glass and carbon fiber composites after water exposure. The transverse strengths of the composites are also degraded to large extents. The tests results identify water degradation of the F/M interface as a major strength limiting mechanism.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, SIK, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Seemingly normal tissues progressively become populated by mutant clones over time. Most of these clones bear mutations in well-known cancer genes but only rarely do they transform into cancer. This ...poses questions on what triggers cancer initiation and what implications somatic variation has for cancer early detection.
We analyzed recent mutational screens of healthy and cancer-free diseased tissues to compare somatic drivers and the causes of somatic variation across tissues. We then reviewed the mechanisms of clonal expansion and their relationships with age and diseases other than cancer. We finally discussed the relevance of somatic variation for cancer initiation and how it can help or hinder cancer detection and prevention.
The extent of somatic variation is highly variable across tissues and depends on intrinsic features, such as tissue architecture and turnover, as well as the exposure to endogenous and exogenous insults. Most somatic mutations driving clonal expansion are tissue-specific and inactivate tumor suppressor genes involved in chromatin modification and cell growth signaling. Some of these genes are more frequently mutated in normal tissues than cancer, indicating a context-dependent cancer-promoting or -protective role. Mutant clones can persist over a long time or disappear rapidly, suggesting that their fitness depends on the dynamic equilibrium with the environment. The disruption of this equilibrium is likely responsible for their transformation into malignant clones and knowing what triggers this process is key for cancer prevention and early detection. Somatic variation should be considered in liquid biopsy, where it may contribute cancer-independent mutations, and in the identification of cancer drivers, since not all mutated genes favoring clonal expansion also drive tumorigenesis.
Somatic variation and the factors governing homeostasis of normal tissues should be taken into account when devising strategies for cancer prevention and early detection.
•Somatic tissues become a patchwork of mutant clones as we age.•The extent of somatic variation depends on tissue features and exposure to insults.•Ninety percent of genes driving somatic clonal expansion are well-known cancer drivers.•Mutations in multiple drivers and chromosomal instability are needed for cancer transformation.•Somatic variation poses challenges but also provides promising opportunities for cancer early detection.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Introduction
The executive function is a complex set of skills affected during the aging process and translate into subclinical cerebrovascular disease. Postural instability or motor slowness are ...some clinical manifestations, being consubstantial with the frailty phenotype, genuine expression of aging. Executive dysfunction is also considered a predictor of adverse health events in the elderly.
Aim
To study whether the executive dysfunction can be used as an early marker for frailty and the viability of use as a predictor of mortality, hospitalization and/or disability in a Mediterranean population.
Design
A population-based cohort study using data from the Toledo Study for Healthy Aging (TSHA).
Methods
1690 Spanish elders aged ≥65 years underwent a neuropsychological evaluation in order to measure executive function. To assess whether the accumulation of dysfunctions (in severity and amplitude) could increase the predictive value of adverse health events in relation to each dimension separately an executive dysfunction cumulative index was constructed. Cox proportional hazards model was used to examine mortality and hospitalization over 5.02 and 3.1 years of follow-up, respectively.
Results
Executive dysfunction is a powerful predictor of mortality, frailty and disability. Cumulative differences in executive function are associated with high risk of frailty and disability, thus, for each one point increment in the executive function index, the risk of death increased by 7 %, frailty by 13% and disability by 11% (P<0.05). Moreover, the executive impairment exhibits a strong positive tendency with age, comorbidity and mortality.
Conclusions
Cumulative differences in four executive dimensions widely used in clinical practice improves the ability to predict frailty and disability compared to each dimension separately.
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EMUNI, GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UILJ, UL, UM, UPCLJ, UPUK, VSZLJ, ZAGLJ, ZRSKP
A fracture mechanics model was developed for determining the fracture toughness of the fiber/matrix (F/M) interface based on a modified test procedure for the single fiber fragmentation test (SFFT). ...After loading the specimen until the first fiber fracture and instantaneous debonding events occur, the specimen is unloaded and loaded again until the debond propagates. The critical load for debond propagation is measured and is used with a fracture mechanics analysis to determine the interface fracture toughness. The analysis considers also friction between the fiber and matrix in the debonded region. To obtain the necessary data for calculation of residual radial stress at the F/M interface due to matrix cure shrinkage, simultaneous measurements of dynamic modulus and cure shrinkage were conducted on the matrix (vinylester) during cure. Tests employing E-glass/vinylester SFFT specimens provided fracture toughness values of
G
cd
=
62
J/m
2 (frictionless) and 48
J/m
2 (friction).
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
In this work, the feasibility of using lignin as a compatibilizer for composites made from jute fiber fabric and polypropylene (PP) was studied. Since lignin contains polar (hydroxyl) groups and ...nonpolar hydrocarbon, it was expected to be able to improve the compatibility between the two components of the composite. It was found that lignin acted as β nucleation, fire retardant, and toughening agent for PP matrix. Jute composites exhibit higher stiffness, tensile strength, and impact behavior in respect to those of neat PP. Although scanning electron micrographic observations indicate that PP-jute adhesion was slightly improved by lignin addition, additional benefits were only obtained from impact behavior.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
10.
Dynamosaicing: Mosaicing of Dynamic Scenes Rav-Acha, A.; Pritch, Y.; Lischinski, D. ...
IEEE transactions on pattern analysis and machine intelligence,
10/2007, Volume:
29, Issue:
10
Journal Article
Peer reviewed
This paper explores the manipulation of time in video editing, which allows us to control the chronological time of events. These time manipulations include slowing down (or postponing) some dynamic ...events while speeding up (or advancing) others. When a video camera scans a scene, aligning all the events to a single time interval will result in a panoramic movie. Time manipulations are obtained by first constructing an aligned space-time volume from the input video, and then sweeping a continuous 2D slice (time front) through that volume, generating a new sequence of images. For dynamic scenes, aligning the input video frames poses an important challenge. We propose to align dynamic scenes using a new notion of "dynamics constancy," which is more appropriate for this task than the traditional assumption of "brightness constancy." Another challenge is to avoid visual seams inside moving objects and other visual artifacts resulting from sweeping the space-time volumes with time fronts of arbitrary geometry. To avoid such artifacts, we formulate the problem of finding optimal time front geometry as one of finding a minimal cut in a 4D graph, and solve it using max-flow methods.
