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51.
Stephanie A C Schuckers Natalia A Schmid Aditya Abhyankar Vivekanand Dorairaj Christopher K Boyce Lawrence A Hornak 《IEEE transactions on systems, man, and cybernetics. Part B, Cybernetics》2007,37(5):1176-1190
The popularity of the iris biometric has grown considerably over the past two to three years. Most research has been focused on the development of new iris processing and recognition algorithms for frontal view iris images. However, a few challenging directions in iris research have been identified, including processing of a nonideal iris and iris at a distance. In this paper, we describe two nonideal iris recognition systems and analyze their performance. The word "nonideal" is used in the sense of compensating for off-angle occluded iris images. The system is designed to process nonideal iris images in two steps: 1) compensation for off-angle gaze direction and 2) processing and encoding of the rotated iris image. Two approaches are presented to account for angular variations in the iris images. In the first approach, we use Daugman's integrodifferential operator as an objective function to estimate the gaze direction. After the angle is estimated, the off-angle iris image undergoes geometric transformations involving the estimated angle and is further processed as if it were a frontal view image. The encoding technique developed for a frontal image is based on the application of the global independent component analysis. The second approach uses an angular deformation calibration model. The angular deformations are modeled, and calibration parameters are calculated. The proposed method consists of a closed-form solution, followed by an iterative optimization procedure. The images are projected on the plane closest to the base calibrated plane. Biorthogonal wavelets are used for encoding to perform iris recognition. We use a special dataset of the off-angle iris images to quantify the performance of the designed systems. A series of receiver operating characteristics demonstrate various effects on the performance of the nonideal-iris-based recognition system. 相似文献
52.
The focus of this article is to review recent techniques in proteomic analysis of ocular fluids. These fluids include tears, aqueous humor, and vitreous, they will also be compared to serum analysis. Furthermore, we attempt to summarize some disease correlated biomarkers in ocular fluids that were discovered through different proteomic techniques in eye diseases like dry eye, glaucoma, age-related macular degeneration, uveitis, or diabetic retinopathy. This review is trying to point out the importance of these biomarkers for clinical applications. 相似文献
53.
Dos Santos A Thiers V Sar S Derian N Bensalem N Yilmaz F Bralet MP Ducot B Bréchot C Demaugre F 《Proteomics. Clinical applications》2007,1(6):545-554
Hepatocellular carcinoma (HCC) is a major cause of cancer worldwide. Proteomic studies provide opportunities to uncover targets for the diagnosis and treatment of this disease. However, in HCC developing in a setting of cirrhosis, the detection of proteome alterations may be hampered by the increased cellular heterogeneity of tissue when analysing global liver homogenates. The aim of this study was to evaluate whether the identification of proteome alterations in these HCC cases was improved when the differential protein profile between tumour and non-tumour areas of liver was determined using hepatocytes isolated by laser microdissection (LM). Differential profiles established with LM-hepatocytes and liver section homogenates using 2-DE and MS exhibited noticeable differences: 30% of the protein spots with deregulated expression in tumorous LM-samples did not display any modification in homogenates; conversely 15% of proteins altered in tumorous homogenates were not impaired in LM-hepatocytes. These alterations resulted from the presence in cirrhotic liver of fibrotic stroma which displayed a protein pattern different from that determined in LM-hepatocytes. In conclusion, our data demonstrate the interest of LM in distinguishing between fibrotic and hepatocyte proteome alterations and thus the benefit of LM to proteome studies of HCC developing in a context of cirrhosis. 相似文献
54.
H. Buggisch H. Bucka F. Reutter H. G. Hahn F. Kolberg H. Unbehauen M. Biermann M. Ziegner H. Kilger H. Brüggemann H. Regenbogen 《Forschung im Ingenieurwesen》1978,44(6):197-200
Ohne Zusammenfassung 相似文献
55.
Emotions have a political dimension in that judgments regarding when and how emotion should be felt and shown are interpreted in the interests of regulating the organization and functioning of social groups. This article argues that claims to authenticity and legitimacy of one's self-identity or group identity are at stake in the everyday politics of emotion. A brief discussion of the study of sex differences in the 19th century illustrates how emotion politics can saturate even scientific inquiry. Three ways in which there is a political dimension to socially appropriate emotion in contemporary life are then discussed: (a) Is the emotion the "wrong" emotion for the situation? (b) How are competing standards for emotional experience and expression managed? and (c) What constitutes the boundary between "too much" and "too little" emotion? The author concludes by considering the relevance of emotion politics to research on emotion. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
56.
Schopp Laura H.; Johnstone Brick; Reid-Arndt Stephanie 《Canadian Metallurgical Quarterly》2005,36(2):158
Rural psychologists are frontline primary behavioral health care providers for nearly 60 million Americans, but they face limited access to peer consultation and continuing education. This article describes a program that matched 70 rehabilitation inpatients who had new brain injury with rural clinicians from patients' home communities. Neuropsychologists provided one-on-one training for clinicians through telehealth video teleconferencing. Clinicians showed gains in brain injury knowledge, and clients rated trained providers higher than untrained providers. Families seeking brain injury services can connect with these trained rural providers through a Web site, which receives more than 800 hits per month. Telehealth offers potential for rural clinicians to receive support, reduce professional isolation, gain working knowledge of specialty conditions, and deliver high-quality services for their rural clients. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
57.
A real-time vision module for interactive perceptual agents 总被引:2,自引:0,他引:2
Bruce A. Maxwell Nathaniel Fairfield Nikolas Johnson Pukar Malla Paul Dickson Suor Kim Stephanie Wojtkowski Thomas Stepleton 《Machine Vision and Applications》2003,14(1):72-82
Abstract. Interactive robotics demands real-time visual information about the environment. Real-time vision processing, however, places
a heavy load on the robot's limited resources, which must accommodate multiple other processes running simultaneously. This
paper describes a vision module capable of providing real-time information from ten or more operators while maintaining at
least a 20-Hz frame rate and leaving sufficient processor time for a robot's other capabilities. The vision module uses a
probabilistic scheduling algorithm to ensure both timely information flow and a fast frame capture. In addition, it tightly
integrates the vision operators with control of a pan-tilt-zoom camera. The vision module makes its information available
to other modules in the robot architecture through a shared memory structure. The information provided by the vision module
includes the operator information along with a time stamp indicating information relevance. Because of this design, our robots
are able to react in a timely manner to a wide variety of visual events. 相似文献
58.
The Challenges of Cross-Modal Translation: English-to-Sign-Language Translation in the Zardoz System
The sign languages used by deaf communities around the world represent a linguistic challenge that natural-language researchers in AI have only recently begun to take up. This challenge is particularly relevant to research in Machine Translation (MT), as natural sign languages have evolved in deaf communities into efficient modes of gestural communication, which differ from English not only in modality but in grammatical structure, exploiting a higher dimensionality of spatial expression. In this paper we describe Zardoz, an on-going AI research system that tackles the cross-modal MT problem, translating English text into fluid sign language. The paper presents an architectural overview of Zardoz, describing its central blackboard organization, the nature of its interlingual representation, and the major components which interact through this blackboard both to analyze the verbal input and generate the corresponding gestural output in one of a number of sign variants. 相似文献
59.
Infant rats exhibit sensitive-period odor learning characterized by olfactory bulb neural changes and odor preference acquisitions critical for survival. This sensitive period is coincident with low endogenous corticosterone (CORT) levels and stress hyporesponsivity. The authors hypothesized that low corticosterone levels modulate sensitive-period learning. They assessed the effects of manipulating CORT levels by increasing and removing CORT during (Postnatal Day 8) and after (Postnatal Day 12) the sensitive period. Results show that (a) exogenous CORT prematurely ends sensitive-period odor-shock-induced preferences; (b) adrenalectomy developmentally extends the sensitive period as indicated by odor-shock-induced odor-preference learning in older pups, whereas CORT replacement can reinstate fear learning; and (c) CORT manipulation modulates olfactory bulb correlates of sensitive-period odor learning in a manner consistent with behavior. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
60.
Sabine Schulze Christin Neuber Stephanie Mller Ute Hempel Lorenz C. Hofbauer Klaus-Dieter Schaser Jens Pietzsch Stefan Rammelt 《International journal of molecular sciences》2022,23(23)
Bone in diabetes mellitus is characterized by an altered microarchitecture caused by abnormal metabolism of bone cells. Together with diabetic neuropathy, this is associated with serious complications including impaired bone healing culminating in complicated fractures and dislocations, especially in the lower extremities, so-called Charcot neuroarthropathy (CN). The underlying mechanisms are not yet fully understood, and treatment of CN is challenging. Several in vitro and in vivo investigations have suggested positive effects on bone regeneration by modifying biomaterials with sulfated glycosaminoglycans (sGAG). Recent findings described a beneficial effect of sGAG for bone healing in diabetic animal models compared to healthy animals. We therefore aimed at studying the effects of low- and high-sulfated hyaluronan derivatives on osteoclast markers as well as gene expression patterns of osteoclasts and osteoblasts from patients with diabetic CN compared to non-diabetic patients with arthritis at the foot and ankle. Exposure to sulfated hyaluronan (sHA) derivatives reduced the exaggerated calcium phosphate resorption as well as the expression of genes associated with bone resorption in both groups, but more pronounced in patients with CN. Moreover, sHA derivatives reduced the release of pro-inflammatory cytokines in osteoclasts of patients with CN. The effects of sHA on osteoblasts differed only marginally between patients with CN and non-diabetic patients with arthritis. These results suggest balancing effects of sHA on osteoclastic bone resorption parameters in diabetes. 相似文献