Comments on the CASIA version 1.0 iris data set.

PubMed

Phillips, P Jonathon; Bowyer, Kevin W; Flynn, Patrick J

2007-10-01

We note that the images in the CASIA version 1.0 iris dataset have been edited so that the pupil area is replaced by a circular region of uniform intensity. We recommend that this dataset is no longer used in iris biometrics research, unless there this a compelling reason that takes into account the nature of the images. In addition, based on our experience with the Iris Challenge Evaluation (ICE) 2005 technology development project, we make recommendations for reporting results of iris recognition experiments.

Computational cameras for moving iris recognition

NASA Astrophysics Data System (ADS)

McCloskey, Scott; Venkatesha, Sharath

2015-05-01

Iris-based biometric identification is increasingly used for facility access and other security applications. Like all methods that exploit visual information, however, iris systems are limited by the quality of captured images. Optical defocus due to a small depth of field (DOF) is one such challenge, as is the acquisition of sharply-focused iris images from subjects in motion. This manuscript describes the application of computational motion-deblurring cameras to the problem of moving iris capture, from the underlying theory to system considerations and performance data.

Early Career Investigator Opportunities in Geophysics with IRIS

NASA Astrophysics Data System (ADS)

Colella, H.; Sumy, D. F.; Schutt, D.

2016-12-01

Early career geoscientists face many challenges as they transition from senior level graduate students into postdoctoral researchers, tenure-track faculty positions, or the vast array of employment opportunities outside of academia. However, few receive adequate mentoring or guidance on how to successfully make the leap from graduate school to a fulfilling career. In recognition of these hurdles and challenges, the Incorporated Research Institutions for Seismology (IRIS) created an early-career investigator (ECI) program in 2011 to help reduce barriers for newly minted scientists, researchers, and educators on their path to success. The core mission of the ECI program is to organize practical resources and professional development opportunities for ECIs. The initiative has encouraged and supported collaboration between ECIs and senior scientists through colloquium lectureships and visiting scientist collaborations, which aimed to increase the visibility of ECIs and their research and to promote interaction between junior and senior scientists outside of their home institutions. Additionally, ECI-centric events are held at various national meetings to showcase the range of career paths available in geophysics, openly discuss the challenges ECIs face (e.g., work-life balance, job search difficulties, teaching challenges), expose participants to the ECI program's initiatives and resources, and better inform IRIS about the needs of the community. Post-workshop evaluations reveal ECIs are eager to have exposure to a variety of workforce options and a forum in which to ask difficult questions. Of note, there is a variety of cultural knowledge and expectations assumed in both the academic and professional worlds that is often not formally disseminated. The ECI program aims to better understand and facilitate transfer of this knowledge and reduce barriers to success for ECIs from both traditional and non-traditional backgrounds. The program also features webinars focused on a range of research and career topics, which can be attended in real-time or viewed on YouTube, with over 6,000 total views to date. Moving forward, an additional focus will be on intentional mentorship opportunities as we continue to build a productive, supportive, and successful early career community.

Next-Generation Ground Network Architecture for Communications and Tracking of Interplanetary Smallsats

NASA Astrophysics Data System (ADS)

Cheung, K.-M.; Abraham, D.; Arroyo, B.; Basilio, E.; Babuscia, A.; Duncan, C.; Lee, D.; Oudrhiri, K.; Pham, T.; Staehle, R.; Waldherr, S.; Welz, G.; Wyatt, J.; Lanucara, M.; Malphrus, B.; Bellardo, J.; Puig-Suari, J.; Corpino, S.

2015-08-01

As small spacecraft venture out of Earth orbit, they will encounter challenges not experienced or addressed by the numerous low Earth orbit (LEO) CubeSat and smallsat missions staged to date. The LEO CubeSats typically use low-cost, proven CubeSat radios, antennas, and university ground stations with small apertures. As more ambitious yet cost-constrained space mission concepts to the Moon and beyond are being developed, CubeSats and smallsats have the potential to provide a more affordable platform for exploring deep space and performing the associated science. Some of the challenges that have, so far, slowed the proliferation of small interplanetary spacecraft are those of communications and navigation. Unlike Earth-orbiting spacecraft that navigate via government services such as North American Aerospace Defense Command's (NORAD's) tracking elements or the Global Positioning Satellite (GPS) system, interplanetary spacecraft would have to operate in a fundamentally different manner that allows the deep-space communications link to provide both command/telemetry and the radiometric data needed for navigation. Another challenge occurs when smallsat and CubeSat missions would involve multiple spacecraft that require near-simultaneous communication and/or navigation, but have a very limited number of ground antenna assets, as well as available spectrum, to support their links. To address these challenges, the Jet Propulsion Laboratory (JPL) and the Deep Space Network (DSN) it operates for NASA are pursuing the following efforts: (1) Developing a CubeSat-compatible, DSN-compatible transponder -- Iris -- which a commercial vendor can then make available as a product line. (2) Developing CubeSat-compatible high-gain antennas -- deployable reflectors, reflectarrays, and inflatable antennas. (3) Streamlining access and utilization processes for DSN and related services such as the Advanced Multi-Mission Operations System (AMMOS). (4) Developing methodologies for tracking and operating multiple spacecraft simultaneously, including spectrum coordination. (5) Coordination and collaboration with non-DSN facilities. This article further describes the communications and tracking challenges facing interplanetary smallsats and CubeSats, and the next-generation ground network architecture being evolved to mitigate those challenges.

Inertial Movements of the Iris as the Origin of Postsaccadic Oscillations.

PubMed

Bouzat, S; Freije, M L; Frapiccini, A L; Gasaneo, G

2018-04-27

Recent studies on the human eye indicate that the pupil moves inside the eyeball due to deformations of the iris. Here we show that this phenomenon can be originated by inertial forces undergone by the iris during the rotation of the eyeball. Moreover, these forces affect the iris in such a way that the pupil behaves effectively as a massive particle. To show this, we develop a model based on the Newton equation on the noninertial reference frame of the eyeball. The model allows us to reproduce and interpret several important findings of recent eye-tracking experiments on saccadic movements. In particular, we get correct results for the dependence of the amplitude and period of the postsaccadic oscillations on the saccade size and also for the peak velocity. The model developed may serve as a tool for characterizing eye properties of individuals.

Inertial Movements of the Iris as the Origin of Postsaccadic Oscillations

NASA Astrophysics Data System (ADS)

Bouzat, S.; Freije, M. L.; Frapiccini, A. L.; Gasaneo, G.

2018-04-01

Recent studies on the human eye indicate that the pupil moves inside the eyeball due to deformations of the iris. Here we show that this phenomenon can be originated by inertial forces undergone by the iris during the rotation of the eyeball. Moreover, these forces affect the iris in such a way that the pupil behaves effectively as a massive particle. To show this, we develop a model based on the Newton equation on the noninertial reference frame of the eyeball. The model allows us to reproduce and interpret several important findings of recent eye-tracking experiments on saccadic movements. In particular, we get correct results for the dependence of the amplitude and period of the postsaccadic oscillations on the saccade size and also for the peak velocity. The model developed may serve as a tool for characterizing eye properties of individuals.

A new phase-correlation-based iris matching for degraded images.

PubMed

Krichen, Emine; Garcia-Salicetti, Sonia; Dorizzi, Bernadette

2009-08-01

In this paper, we present a new phase-correlation-based iris matching approach in order to deal with degradations in iris images due to unconstrained acquisition procedures. Our matching system is a fusion of global and local Gabor phase-correlation schemes. The main originality of our local approach is that we do not only consider the correlation peak amplitudes but also their locations in different regions of the images. Results on several degraded databases, namely, the CASIA-BIOSECURE and Iris Challenge Evaluation 2005 databases, show the improvement of our method compared to two available reference systems, Masek and Open Source for Iris (OSRIS), in verification mode.

Under the hood of IRIS's Distributed REU Site

NASA Astrophysics Data System (ADS)

Hubenthal, M.; Taber, J.

2014-12-01

Since 1998 the IRIS Undergraduate Internship Program has provided research experiences for up to 15 students each summer. Through this 9 to 11 week internship program, students take part in an intensive week-long preparatory course, and work with leaders in seismological research, in both lab-base and field-based settings, to produce research products worthy of presentation and recognition at large professional conferences. The IRIS internship program employs a distributed REU model that has been demonstrated to bond students into a cohort, and maintain group cohesion despite students conducting their research at geographically distributed sites. Over the past 16 years the program has encountered numerous anticipated and unanticipated challenges. The primary challenges have involved exploring how to modify the REU-system to produce outcomes that are better aligned with our programmatic goals. For example, some questions we have attempted to address include: How can the success of an REU site be measured? How do you find, interest, and recruit under-represented minorities into a geophysics program? Can the program increase the probability of interns receiving some minimal level of mentoring across the program? While it is likely that no single answer to these questions exists, we have developed and piloted a number of strategies. These approaches have been developed through a process of identifying relevant research results from other REUs and combing this information with data from our own programmatic evaluations. This data informs the development of specific changes within our program which are then measured as a feedback. We will present our current strategies to address each questions along with measures of their effectiveness. In addition to broad scale systematic issues, we have also placed significant effort into responding to smaller, process challenges that all REU sites face. These range from simple logistical issues (e.g. liability), to educational issues (e.g. what "assignments" are meaningful but not so overwhelming as to take away from research time), to longer term issues such as building an effective alumni network, tracking participants, and maintaining funding. While each REU is unique, we will share our approaches to dealing with these issues, as such topics may be of use to other REUs.

Exploring the feasibility of iris recognition for visible spectrum iris images obtained using smartphone camera

NASA Astrophysics Data System (ADS)

Trokielewicz, Mateusz; Bartuzi, Ewelina; Michowska, Katarzyna; Andrzejewska, Antonina; Selegrat, Monika

2015-09-01

In the age of modern, hyperconnected society that increasingly relies on mobile devices and solutions, implementing a reliable and accurate biometric system employing iris recognition presents new challenges. Typical biometric systems employing iris analysis require expensive and complicated hardware. We therefore explore an alternative way using visible spectrum iris imaging. This paper aims at answering several questions related to applying iris biometrics for images obtained in the visible spectrum using smartphone camera. Can irides be successfully and effortlessly imaged using a smartphone's built-in camera? Can existing iris recognition methods perform well when presented with such images? The main advantage of using near-infrared (NIR) illumination in dedicated iris recognition cameras is good performance almost independent of the iris color and pigmentation. Are the images obtained from smartphone's camera of sufficient quality even for the dark irides? We present experiments incorporating simple image preprocessing to find the best visibility of iris texture, followed by a performance study to assess whether iris recognition methods originally aimed at NIR iris images perform well with visible light images. To our best knowledge this is the first comprehensive analysis of iris recognition performance using a database of high-quality images collected in visible light using the smartphones flashlight together with the application of commercial off-the-shelf (COTS) iris recognition methods.

Challenges in diagnosis and management of Cryptococcal immune reconstitution inflammatory syndrome (IRIS) in resource limited settings.

PubMed

Musubire, A K; Meya, B D; Mayanja-Kizza, H; Lukande, R; Wiesner, L D; Bohjanen, P; R Boulware, R D

2012-06-01

In many resource-limited settings, cryptococcal meningitis (CM) contributes up to 20% of all deaths with further complications due to Immune Reconstitution Inflammatory Syndrome (IRIS). We present a case report on a patient who developed CM-IRIS and then subsequent CM-relapse with a fluconazole-resistant organism and then later CM-IRIS once again, manifesting as cystic cryptococcomas, hydrocephalus, and sterile CSF. In this case we, demonstrate that CM-IRIS and persistent low level cryptococcal infection are not mutually exclusive phenomena. The management of IRIS with corticosteroids may increase the risk of culture positive CM-relapse which may further increase the risk of recurrent IRIS and resulting complications including death. We also highlight the role of imaging and fluconazole resistance testing in patients with recurrent meningitis and the importance of CSF cultures in guiding treatment decisions.

IRIS TOXICOLOGICAL REVIEW AND SUMMARY ...

EPA Pesticide Factsheets

The known toxic effects of perchloroethylene will be summarized, with citations from current scientific literature. The critical effects will be identified, and from this the RfD and RfC and cancer unit risk factors will be derived. The RfD and RfC are reference doses and air concentrations that are generally regarded as safe under conditions of chronic exposure. The cancer unit risks in air and drinking water are the estimated lifetime cancer risks expected to occur from a lifetime exposure to a concentration of 1 microgram per cubic meter in the air and to a drinking water concentration of 1 microgram per liter. This summary document will be peer reviewed within the Agency and by experts outside the Agency according to the standard IRIS procedures. For up-to-date project schedules see IRIS Track at http://cfpub.epa.gov/iristrac/index.cfm The U.S. EPA is conducting a new health assessment of tetrachloroethylene that will appear on the Agency's online database, the Integrated Risk Information System (IRIS). IRIS is an EPA database containing Agency scientific positions on potential adverse human health effects that may result from chronic (or lifetime) exposure to chemicals in the environment. IRIS contains chemical-specific summaries of qualitative and quantitative health information in support of two steps of the risk assessment process, i.e., hazard identification and dose-response evaluation. IRIS assessments are used in combination with specific sit

Multi-Patches IRIS Based Person Authentication System Using Particle Swarm Optimization and Fuzzy C-Means Clustering

NASA Astrophysics Data System (ADS)

Shekar, B. H.; Bhat, S. S.

2017-05-01

Locating the boundary parameters of pupil and iris and segmenting the noise free iris portion are the most challenging phases of an automated iris recognition system. In this paper, we have presented person authentication frame work which uses particle swarm optimization (PSO) to locate iris region and circular hough transform (CHT) to device the boundary parameters. To undermine the effect of the noise presented in the segmented iris region we have divided the candidate region into N patches and used Fuzzy c-means clustering (FCM) to classify the patches into best iris region and not so best iris region (noisy region) based on the probability density function of each patch. Weighted mean Hammimng distance is adopted to find the dissimilarity score between the two candidate irises. We have used Log-Gabor, Riesz and Taylor's series expansion (TSE) filters and combinations of these three for iris feature extraction. To justify the feasibility of the proposed method, we experimented on the three publicly available data sets IITD, MMU v-2 and CASIA v-4 distance.

Toward accurate and fast iris segmentation for iris biometrics.

PubMed

He, Zhaofeng; Tan, Tieniu; Sun, Zhenan; Qiu, Xianchao

2009-09-01

Iris segmentation is an essential module in iris recognition because it defines the effective image region used for subsequent processing such as feature extraction. Traditional iris segmentation methods often involve an exhaustive search of a large parameter space, which is time consuming and sensitive to noise. To address these problems, this paper presents a novel algorithm for accurate and fast iris segmentation. After efficient reflection removal, an Adaboost-cascade iris detector is first built to extract a rough position of the iris center. Edge points of iris boundaries are then detected, and an elastic model named pulling and pushing is established. Under this model, the center and radius of the circular iris boundaries are iteratively refined in a way driven by the restoring forces of Hooke's law. Furthermore, a smoothing spline-based edge fitting scheme is presented to deal with noncircular iris boundaries. After that, eyelids are localized via edge detection followed by curve fitting. The novelty here is the adoption of a rank filter for noise elimination and a histogram filter for tackling the shape irregularity of eyelids. Finally, eyelashes and shadows are detected via a learned prediction model. This model provides an adaptive threshold for eyelash and shadow detection by analyzing the intensity distributions of different iris regions. Experimental results on three challenging iris image databases demonstrate that the proposed algorithm outperforms state-of-the-art methods in both accuracy and speed.

Managing distributed software development in the Virtual Astronomical Observatory

NASA Astrophysics Data System (ADS)

Evans, Janet D.; Plante, Raymond L.; Boneventura, Nina; Busko, Ivo; Cresitello-Dittmar, Mark; D'Abrusco, Raffaele; Doe, Stephen; Ebert, Rick; Laurino, Omar; Pevunova, Olga; Refsdal, Brian; Thomas, Brian

2012-09-01

The U.S. Virtual Astronomical Observatory (VAO) is a product-driven organization that provides new scientific research capabilities to the astronomical community. Software development for the VAO follows a lightweight framework that guides development of science applications and infrastructure. Challenges to be overcome include distributed development teams, part-time efforts, and highly constrained schedules. We describe the process we followed to conquer these challenges while developing Iris, the VAO application for analysis of 1-D astronomical spectral energy distributions (SEDs). Iris was successfully built and released in less than a year with a team distributed across four institutions. The project followed existing International Virtual Observatory Alliance inter-operability standards for spectral data and contributed a SED library as a by-product of the project. We emphasize lessons learned that will be folded into future development efforts. In our experience, a well-defined process that provides guidelines to ensure the project is cohesive and stays on track is key to success. Internal product deliveries with a planned test and feedback loop are critical. Release candidates are measured against use cases established early in the process, and provide the opportunity to assess priorities and make course corrections during development. Also key is the participation of a stakeholder such as a lead scientist who manages the technical questions, advises on priorities, and is actively involved as a lead tester. Finally, frequent scheduled communications (for example a bi-weekly tele-conference) assure issues are resolved quickly and the team is working toward a common vision.

An iris recognition algorithm based on DCT and GLCM

NASA Astrophysics Data System (ADS)

Feng, G.; Wu, Ye-qing

2008-04-01

With the enlargement of mankind's activity range, the significance for person's status identity is becoming more and more important. So many different techniques for person's status identity were proposed for this practical usage. Conventional person's status identity methods like password and identification card are not always reliable. A wide variety of biometrics has been developed for this challenge. Among those biologic characteristics, iris pattern gains increasing attention for its stability, reliability, uniqueness, noninvasiveness and difficult to counterfeit. The distinct merits of the iris lead to its high reliability for personal identification. So the iris identification technique had become hot research point in the past several years. This paper presents an efficient algorithm for iris recognition using gray-level co-occurrence matrix(GLCM) and Discrete Cosine transform(DCT). To obtain more representative iris features, features from space and DCT transformation domain are extracted. Both GLCM and DCT are applied on the iris image to form the feature sequence in this paper. The combination of GLCM and DCT makes the iris feature more distinct. Upon GLCM and DCT the eigenvector of iris extracted, which reflects features of spatial transformation and frequency transformation. Experimental results show that the algorithm is effective and feasible with iris recognition.

VASIR: An Open-Source Research Platform for Advanced Iris Recognition Technologies.

PubMed

Lee, Yooyoung; Micheals, Ross J; Filliben, James J; Phillips, P Jonathon

2013-01-01

The performance of iris recognition systems is frequently affected by input image quality, which in turn is vulnerable to less-than-optimal conditions due to illuminations, environments, and subject characteristics (e.g., distance, movement, face/body visibility, blinking, etc.). VASIR (Video-based Automatic System for Iris Recognition) is a state-of-the-art NIST-developed iris recognition software platform designed to systematically address these vulnerabilities. We developed VASIR as a research tool that will not only provide a reference (to assess the relative performance of alternative algorithms) for the biometrics community, but will also advance (via this new emerging iris recognition paradigm) NIST's measurement mission. VASIR is designed to accommodate both ideal (e.g., classical still images) and less-than-ideal images (e.g., face-visible videos). VASIR has three primary modules: 1) Image Acquisition 2) Video Processing, and 3) Iris Recognition. Each module consists of several sub-components that have been optimized by use of rigorous orthogonal experiment design and analysis techniques. We evaluated VASIR performance using the MBGC (Multiple Biometric Grand Challenge) NIR (Near-Infrared) face-visible video dataset and the ICE (Iris Challenge Evaluation) 2005 still-based dataset. The results showed that even though VASIR was primarily developed and optimized for the less-constrained video case, it still achieved high verification rates for the traditional still-image case. For this reason, VASIR may be used as an effective baseline for the biometrics community to evaluate their algorithm performance, and thus serves as a valuable research platform.

VASIR: An Open-Source Research Platform for Advanced Iris Recognition Technologies

PubMed Central

Lee, Yooyoung; Micheals, Ross J; Filliben, James J; Phillips, P Jonathon

2013-01-01

The performance of iris recognition systems is frequently affected by input image quality, which in turn is vulnerable to less-than-optimal conditions due to illuminations, environments, and subject characteristics (e.g., distance, movement, face/body visibility, blinking, etc.). VASIR (Video-based Automatic System for Iris Recognition) is a state-of-the-art NIST-developed iris recognition software platform designed to systematically address these vulnerabilities. We developed VASIR as a research tool that will not only provide a reference (to assess the relative performance of alternative algorithms) for the biometrics community, but will also advance (via this new emerging iris recognition paradigm) NIST’s measurement mission. VASIR is designed to accommodate both ideal (e.g., classical still images) and less-than-ideal images (e.g., face-visible videos). VASIR has three primary modules: 1) Image Acquisition 2) Video Processing, and 3) Iris Recognition. Each module consists of several sub-components that have been optimized by use of rigorous orthogonal experiment design and analysis techniques. We evaluated VASIR performance using the MBGC (Multiple Biometric Grand Challenge) NIR (Near-Infrared) face-visible video dataset and the ICE (Iris Challenge Evaluation) 2005 still-based dataset. The results showed that even though VASIR was primarily developed and optimized for the less-constrained video case, it still achieved high verification rates for the traditional still-image case. For this reason, VASIR may be used as an effective baseline for the biometrics community to evaluate their algorithm performance, and thus serves as a valuable research platform. PMID:26401431

On techniques for angle compensation in nonideal iris recognition.

PubMed

Schuckers, Stephanie A C; Schmid, Natalia A; Abhyankar, Aditya; Dorairaj, Vivekanand; Boyce, Christopher K; Hornak, Lawrence A

2007-10-01

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.

Secure and Robust Iris Recognition Using Random Projections and Sparse Representations.

PubMed

Pillai, Jaishanker K; Patel, Vishal M; Chellappa, Rama; Ratha, Nalini K

2011-09-01

Noncontact biometrics such as face and iris have additional benefits over contact-based biometrics such as fingerprint and hand geometry. However, three important challenges need to be addressed in a noncontact biometrics-based authentication system: ability to handle unconstrained acquisition, robust and accurate matching, and privacy enhancement without compromising security. In this paper, we propose a unified framework based on random projections and sparse representations, that can simultaneously address all three issues mentioned above in relation to iris biometrics. Our proposed quality measure can handle segmentation errors and a wide variety of possible artifacts during iris acquisition. We demonstrate how the proposed approach can be easily extended to handle alignment variations and recognition from iris videos, resulting in a robust and accurate system. The proposed approach includes enhancements to privacy and security by providing ways to create cancelable iris templates. Results on public data sets show significant benefits of the proposed approach.

Challenging ocular image recognition

NASA Astrophysics Data System (ADS)

Pauca, V. Paúl; Forkin, Michael; Xu, Xiao; Plemmons, Robert; Ross, Arun A.

2011-06-01

Ocular recognition is a new area of biometric investigation targeted at overcoming the limitations of iris recognition performance in the presence of non-ideal data. There are several advantages for increasing the area beyond the iris, yet there are also key issues that must be addressed such as size of the ocular region, factors affecting performance, and appropriate corpora to study these factors in isolation. In this paper, we explore and identify some of these issues with the goal of better defining parameters for ocular recognition. An empirical study is performed where iris recognition methods are contrasted with texture and point operators on existing iris and face datasets. The experimental results show a dramatic recognition performance gain when additional features are considered in the presence of poor quality iris data, offering strong evidence for extending interest beyond the iris. The experiments also highlight the need for the direct collection of additional ocular imagery.

Limbus Impact on Off-angle Iris Degradation

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

Karakaya, Mahmut; Barstow, Del R; Santos-Villalobos, Hector J

The accuracy of iris recognition depends on the quality of data capture and is negatively affected by several factors such as angle, occlusion, and dilation. Off-angle iris recognition is a new research focus in biometrics that tries to address several issues including corneal refraction, complex 3D iris texture, and blur. In this paper, we present an additional significant challenge that degrades the performance of the off-angle iris recognition systems, called the limbus effect . The limbus is the region at the border of the cornea where the cornea joins the sclera. The limbus is a semitransparent tissue that occludes amore » side portion of the iris plane. The amount of occluded iris texture on the side nearest the camera increases as the image acquisition angle increases. Without considering the role of the limbus effect, it is difficult to design an accurate off-angle iris recognition system. To the best of our knowledge, this is the first work that investigates the limbus effect in detail from a biometrics perspective. Based on results from real images and simulated experiments with real iris texture, the limbus effect increases the hamming distance score between frontal and off-angle iris images ranging from 0.05 to 0.2 depending upon the limbus height.« less

Iris ultrastructure in patients with synechiae as revealed by in vivo laser scanning confocal microscopy : In vivo iris ultrastructure in patients with Synechiae by Laser Scanning Confocal Microscopy.

PubMed

Li, Ming; Cheng, Hongbo; Guo, Ping; Zhang, Chun; Tang, Song; Wang, Shusheng

2016-04-26

Iris plays important roles in ocular physiology and disease pathogenesis. Currently it is technically challenging to noninvasively examine the human iris ultrastructure in vivo. The purpose of the current study is to reveal human iris ultrastructure in patients with synechiae by using noninvasive in vivo laser scanning confocal microscopy (LSCM). The ultrastructure of iris in thirty one patients, each with synechiae but transparent cornea, was examined by in vivo LSCM. Five characteristic iris ultrastructures was revealed in patients with synechiae by in vivo LSCM, which include: 1. tree trunk-like structure; 2. tree branch/bush-like structure; 3. Fruit-like structure; 4. Epithelioid-like structure; 5. deep structure. Pigment granules can be observed as a loose structure on the top of the arborization structure. In iris-associated diseases with Tyndall's Phenomenon and keratic precipitates, the pigment particles are more likely to fall off from the arborization structure. The ultrastructure of iris in patients with synechiae has been visualized using in vivo LSCM. Five iris ultrastructures can be clearly observed, with some of the structures maybe disease-associated. The fall-off of the pigment particles may cause the Tyndall's Phenomenon positive. In vivo LSCM provides a non-invasive approach to observe the human iris ultrastructure under certain eye disease conditions, which sets up a foundation to visualize certain iris-associated diseases in the future.

Enhanced way of securing automated teller machine to track the misusers using secure monitor tracking analysis

NASA Astrophysics Data System (ADS)

Sadhasivam, Jayakumar; Alamelu, M.; Radhika, R.; Ramya, S.; Dharani, K.; Jayavel, Senthil

2017-11-01

Now a days the people's attraction towards Automated Teller Machine(ATM) has been increasing even in rural areas. As of now the security provided by all the bank is ATM pin number. Hackers know the way to easily identify the pin number and withdraw money if they haven stolen the ATM card. Also, the Automated Teller Machine is broken and the money is stolen. To overcome these disadvantages, we propose an approach “Automated Secure Tracking System” to secure and tracking the changes in ATM. In this approach, while creating the bank account, the bank should scan the iris known (a part or movement of our eye) and fingerprint of the customer. The scanning can be done with the position of the eye movements and fingerprints identified with the shortest measurements. When the card is swiped then ATM should request the pin, scan the iris and recognize the fingerprint and then allow the customer to withdraw money. If somebody tries to break the ATM an alert message is given to the nearby police station and the ATM shutter is automatically closed. This helps in avoiding the hackers who withdraw money by stealing the ATM card and also helps the government in identifying the criminals easily.

The Changing Landscape of Chemical Toxicity Values and Challenges Presented with Trichloroethylene

DTIC Science & Technology

2012-12-11

become Risk Management Actions (RMAs) BUILDING STRONG® IRIS Documents Reviewed by DoD Services  Benzo(a)pyrene  Trimethylbenzenes  Dioxin ...4 BUILDING STRONG® Other Chemicals of DoD Interest Undergoing IRIS Reassessment  1,4-Dioxane  Dioxin (cancer)  RDX  Arsenic

On a methodology for robust segmentation of nonideal iris images.

PubMed

Schmid, Natalia A; Zuo, Jinyu

2010-06-01

Iris biometric is one of the most reliable biometrics with respect to performance. However, this reliability is a function of the ideality of the data. One of the most important steps in processing nonideal data is reliable and precise segmentation of the iris pattern from remaining background. In this paper, a segmentation methodology that aims at compensating various nonidealities contained in iris images during segmentation is proposed. The virtue of this methodology lies in its capability to reliably segment nonideal imagery that is simultaneously affected with such factors as specular reflection, blur, lighting variation, occlusion, and off-angle images. We demonstrate the robustness of our segmentation methodology by evaluating ideal and nonideal data sets, namely, the Chinese Academy of Sciences iris data version 3 interval subdirectory, the iris challenge evaluation data, the West Virginia University (WVU) data, and the WVU off-angle data. Furthermore, we compare our performance to that of our implementation of Camus and Wildes's algorithm and Masek's algorithm. We demonstrate considerable improvement in segmentation performance over the formerly mentioned algorithms.

Results of the IRIS UV Burst Survey, Part I: Active Regions Tracked Limb to Limb

NASA Astrophysics Data System (ADS)

Madsen, C. A.; DeLuca, E.

2017-12-01

We present results from the first phase of an effort to thoroughly characterize UV bursts within the Interface Region Imaging Spectrograph (IRIS) data catalogue. The observational signatures of these phenomena include dramatically intensified and broadened NUV/FUV emission line profiles with absorption features from cool metallic ions. These properties suggest that UV bursts originate from plasma at transition region temperatures (≥ 80,000 K) which is deeply embedded in the cool lower chromosphere ( 5,000 K). Rigorously characterizing the energetic and dynamical properties of UV bursts is crucial since they have considerable potential to heat active region chromospheres and could provide critical constraints for models of magnetic reconnection in these regions. The survey first focuses on IRIS observations of active regions tracked from limb to limb. All observations consist of large field-of-view raster scans of 320 or 400 steps each, which allow for widespread detection of many burst profiles at the expense of having limited short-term time evolution information. We detect bursts efficiently by applying a semi-automated single-Gaussian fitting technique to Si IV 1393.8 Å emission profiles that isolates the distinct burst population in a 4-D parameter space. The robust sample of NUV/FUV burst spectra allows for precise constraints of properties critical for modeling reconnection in the chromosphere, including outflow kinetic energy, density estimates from intensity ratios of Si IV 1402.8 Å and O IV 1401.2 Å emission lines, and coincident measures of emission in other wavelengths. We also track burst properties throughout the lifetimes of their host active regions, noting changes in detection rate and preferential location as the active regions evolve. Finally, the tracked active region observations provide a unique opportunity to investigate line-of-sight effects on observed UV burst spectral properties, particularly the strength of Ni II 1393.3 Å absorption, a feature that may be important in identifying the upward conduction of burst thermal energy through the chromosphere.

Examples of Level Products Possible from Existing Assets

NASA Technical Reports Server (NTRS)

Quattrochi, Dale A.

2012-01-01

How do patterns of human environmental and infectious diseases respond to leading environmental changes, particularly to urban growth and change and the associated impacts of urbanization? We use HyspIRI high spatial resolution, multispectral, and multitemporal TIR data to track energy balance and energy flux characteristics for changing land covers/land uses through time to provide synoptic views of impacts on surface energy fluxes, emissivity and temperature and HyspIRI data in conjunction with spatial growth models to project land cover/land use changes in the future to assess impacts on natural and human ecosystems. We use multispectral thermal IR land cover maps at a high spatial resolution (60m) on a weekly basis for long-term validation of surface energy responses and changes in emissivity and integration of HyspIRI TIR data with spatial modeling to assess changes in land cover/land use through time and subsequent changes in thermal energy responses

Iris recognition: on the segmentation of degraded images acquired in the visible wavelength.

PubMed

Proença, Hugo

2010-08-01

Iris recognition imaging constraints are receiving increasing attention. There are several proposals to develop systems that operate in the visible wavelength and in less constrained environments. These imaging conditions engender acquired noisy artifacts that lead to severely degraded images, making iris segmentation a major issue. Having observed that existing iris segmentation methods tend to fail in these challenging conditions, we present a segmentation method that can handle degraded images acquired in less constrained conditions. We offer the following contributions: 1) to consider the sclera the most easily distinguishable part of the eye in degraded images, 2) to propose a new type of feature that measures the proportion of sclera in each direction and is fundamental in segmenting the iris, and 3) to run the entire procedure in deterministically linear time in respect to the size of the image, making the procedure suitable for real-time applications.

Development of Fiber Reinforced Track Pad Materials

DTIC Science & Technology

1986-04-01

Transfer and Vulcanization of Rubber , I.R.I. Monograph, Elsevier, 1971. 12 Bergstrom, E.W., " Wear Resistant Rubber Tank Track Pads," Rock Island Arsenal...Fracture Mechanics to Rubber Articles, Including Tyres ," Phil. Trans. R. Soc. Lond. A299,,189-202 (1981). 10 Gent, Fielding-Russell, Livingston, and...System for Rubber Bonded to Brass-Plated Steel Tyre Cord," NR Technology, vol 11, Part 2, 1980, pp 21-27. 16 Lindley, P.B., Engineering Design with

Analysis of West African Drug Trafficking: The Dynamics of Interdiction and State Capacity

DTIC Science & Technology

2011-03-01

www.unodc.org/southerncone/en/frontpage/2010/05/21-cooperacao-internacional-brasil- forma - oficiais-que-irao-administrar-academia-de-policia-na-guine...Side of Globalization. Tracking Globalization. Bloomington: Indiana University Press, 2005. Vaz, Nuno and Iris Cordelia Rotzoll. “Presidential

Excimer Laser Surgery: Biometrical Iris Eye Recognition with Cyclorotational Control Eye Tracker System.

PubMed

Pajic, Bojan; Cvejic, Zeljka; Mijatovic, Zoran; Indjin, Dragan; Mueller, Joerg

2017-05-25

A prospective comparative study assessing the importance of the intra-operative dynamic rotational tracking-especially in the treatment of astigmatisms in corneal refractive Excimer laser correction-concerning clinical outcomes is presented. The cyclotorsion from upright to supine position was measured using iris image comparison. The Group 1 of patients was additionally treated with cyclorotational control and Group 2 only with X-Y control. Significant differences were observed between the groups regarding the mean postoperative cylinder refraction ( p < 0.05). The mean cyclotorsion can be calculated to 3.75° with a standard deviation of 3.1°. The total range of torsion was from -14.9° to +12.6°. Re-treatment rate was 2.2% in Group 1 and 8.2% in Group 2, which is highly significant ( p < 0.01). The investigation confirms that the dynamic rotational tracking system used for LASIK results in highly predictable refraction quality with significantly less postoperative re-treatments.

A new method for generating an invariant iris private key based on the fuzzy vault system.

PubMed

Lee, Youn Joo; Park, Kang Ryoung; Lee, Sung Joo; Bae, Kwanghyuk; Kim, Jaihie

2008-10-01

Cryptographic systems have been widely used in many information security applications. One main challenge that these systems have faced has been how to protect private keys from attackers. Recently, biometric cryptosystems have been introduced as a reliable way of concealing private keys by using biometric data. A fuzzy vault refers to a biometric cryptosystem that can be used to effectively protect private keys and to release them only when legitimate users enter their biometric data. In biometric systems, a critical problem is storing biometric templates in a database. However, fuzzy vault systems do not need to directly store these templates since they are combined with private keys by using cryptography. Previous fuzzy vault systems were designed by using fingerprint, face, and so on. However, there has been no attempt to implement a fuzzy vault system that used an iris. In biometric applications, it is widely known that an iris can discriminate between persons better than other biometric modalities. In this paper, we propose a reliable fuzzy vault system based on local iris features. We extracted multiple iris features from multiple local regions in a given iris image, and the exact values of the unordered set were then produced using the clustering method. To align the iris templates with the new input iris data, a shift-matching technique was applied. Experimental results showed that 128-bit private keys were securely and robustly generated by using any given iris data without requiring prealignment.

Texture Feature Extraction and Classification for Iris Diagnosis

NASA Astrophysics Data System (ADS)

Ma, Lin; Li, Naimin

Appling computer aided techniques in iris image processing, and combining occidental iridology with the traditional Chinese medicine is a challenging research area in digital image processing and artificial intelligence. This paper proposes an iridology model that consists the iris image pre-processing, texture feature analysis and disease classification. To the pre-processing, a 2-step iris localization approach is proposed; a 2-D Gabor filter based texture analysis and a texture fractal dimension estimation method are proposed for pathological feature extraction; and at last support vector machines are constructed to recognize 2 typical diseases such as the alimentary canal disease and the nerve system disease. Experimental results show that the proposed iridology diagnosis model is quite effective and promising for medical diagnosis and health surveillance for both hospital and public use.

[Correction of aphakia with the implantation of the retropupillary iris clip intraocular artificial lens].

PubMed

Szabó, Antal; Papp, András; Borbándy, Ágnes; D Géhl, Zsuzsanna; Nagy, Zoltán Zsolt; Resch, Miklós

2017-01-01

The correction of aphakia might be a challenge for the surgeon. The aim of this study is to describe the authors' experience with the implantation of the retropupillary iris clip intraocular lens. Patients between January 2014 and December 2015 were included in the retrospective study. Retropupillary implantation of iris clip intraocular lens VRSA 54 (AMO Advanced Medical Optics, USA) was performed in all cases. The minimum follow up period was three months. The stability of the intraocular lens and the intraoperative and postoperative complications and the visual acuity were evaluated. During this time period 11 cases (1 female, 10 males) were included in the study. The mean age at the time of the implantation was 57.7 years (between 25-74 years). In 4 cases the iris clip lens was implanted during the first intervention, in 7 cases during the secondary procedure. In all cases the lens was fixated onto the iris posteriorly. The best corrected visual acuity before the iris clip implantation was 0.43 (0.1-1.0) and postoperatively at the time of the follow up 0.49 (0.04-1.0). With the use of the retropupillary implanted iris clip intraocular lens all of the patients could have been rehabilitated without major complications. Orv. Hetil., 2017, 158(1), 20-24.

Management of complications of cosmetic iris implants in a phakic eye: a case report and literature review.

PubMed

Bore, Millicent; Choudhari, Nikhil; Chaurasia, Sunita

2018-03-21

To report the intricacies of managing complications that arose out of cosmetic iris implants (BrightOcular) placement. Interventional case report. A thirty-year-old gentleman presented with complaint of progressive loss of vision after having cosmetic iris implant surgery to change his eye colour. He then developed raised intraocular pressures and had a right eye trabeculectomy conducted with the implants in situ. Subsequently, he had implant removal surgery because of persistent implant-associated complications. The vision was impaired due to progressive corneal oedema and glaucoma. Various considerations were taken while planning for surgical intervention because of the extensive structural damage to the anterior segment of the eye. This case report highlights that cosmetic iris implants are dangerous intraocular devices and management of the associated complications is also challenging. As these devices cause irreversible structural and functional damage, their use should be discouraged in normal eyes.

Propagating wave in active region-loops, located over the solar disk observed by the Interface Region Imaging Spectrograph

NASA Astrophysics Data System (ADS)

Zhang, B.; Hou, Y. J.; Zhang, J.

2018-03-01

Aims: We aim to ascertain the physical parameters of a propagating wave over the solar disk detected by the Interface Region Imaging Spectrograph (IRIS). Methods: Using imaging data from the IRIS and the Solar Dynamic Observatory (SDO), we tracked bright spots to determine the parameters of a propagating transverse wave in active region (AR) loops triggered by activation of a filament. Deriving the Doppler velocity of Si IV line from spectral observations of IRIS, we have determined the rotating directions of active region loops which are relevant to the wave. Results: On 2015 December 19, a filament was located on the polarity inversion line of the NOAA AR 12470. The filament was activated and then caused a C1.1 two-ribbon flare. Between the flare ribbons, two rotation motions of a set of bright loops were observed to appear in turn with opposite directions. Following the end of the second rotation, a propagating wave and an associated transverse oscillation were detected in these bright loops. In 1400 Å channel, there was bright material flowing along the loops in a wave-like manner, with a period of 128 s and a mean amplitude of 880 km. For the transverse oscillation, we tracked a given loop and determine the transverse positions of the tracking loop in a limited longitudinal range. In both of 1400 Å and 171 Å channels, approximately four periods are distinguished during the transverse oscillation. The mean period of the oscillation is estimated as 143 s and the displacement amplitude as between 1370 km and 690 km. We interpret these oscillations as a propagating kink wave and obtain its speed of 1400 km s-1. Conclusions: Our observations reveal that a flare associated with filament activation could trigger a kink propagating wave in active region loops over the solar disk. Movies associated to Figs. 1-4 are available at http://https://www.aanda.org

Spectra Handling from AIRS and IRIS for Climate Change Research

NASA Astrophysics Data System (ADS)

Jiang, Y.; Lau, M.; Aumann, H. H.; Yung, Y. L.

2010-12-01

Outgoing longwave radiation (OLR) measurements over a long period from satellites provide valuable information for the climate change research. Due to the different coverage, spectral resolution and instrument sensitivities, the data comparisons between different satellites could be problematic and possible artifacts could be easily introduced. In this paper, we have analyzed the data taken by IRIS in 1970 and by AIRS from 2002 to 2010. IRIS (Prabhakara, 1988) was a Fourier transform spectrometer (FTS) and it flew on the NASA Nimbus 4 satellite which was launched in April 1970 into an 1100km altitude sun-synchronous polar orbit. It collected data from the nadir track between 400cm-1 and 1600 cm-1 from April 1970 until January 1971. AIRS (Aumann, 2003) is a grating spectrometer launched on the EOS-Aqua satellite in May 2002 and it measures spectra from 650cm-1 to 2700cm-1. AIRS scans to ±49.5o cross track as the satellite moves forwards taking 90 spectra each with an instantaneous field of view of 1.1o in a row perpendicular to the direction of motion of the satellite. This results in a ground footprint of 13km diameter at nadir. In this paper, we analyzed the spectra between 650 cm-1 and 1350 cm-1 for nadir view footprints in order to match the IRIS’s measurements. Most of the possible sources of error or biases have been carefully handled, these include the errors from the data editing, spatial coverage, missing data (spatial gap), and spectral resolution, spectra frequency shift due to the fields of view, sea surface temperature fluctuations, clear sky determination, and spectra response function symmetry. It is extremely important when comparing spectra in the high slope spectra regions where possible large artifacts could be introduced. We have used a radiative model to simulate the spectra as observed in both IRIS and AIRS by using US Standard Atmospheric Profiles. The tropospheric warming and stratospheric warming are introduced in the model as well. The model shows consistent spectra for both clear sky and low cloud with both AIRS and IRIS by introducing water vapor in the model. The model results indicate the CO2 and CH4 increase which is consistent with the IPCC report. Due to the broad emission range of the water vapor in the troposphere, it plays a significant role in the model simulations.

Integrated radiotherapy imaging system (IRIS): design considerations of tumour tracking with linac gantry-mounted diagnostic x-ray systems with flat-panel detectors

NASA Astrophysics Data System (ADS)

Berbeco, Ross I.; Jiang, Steve B.; Sharp, Gregory C.; Chen, George T. Y.; Mostafavi, Hassan; Shirato, Hiroki

2004-01-01

The design of an integrated radiotherapy imaging system (IRIS), consisting of gantry mounted diagnostic (kV) x-ray tubes and fast read-out flat-panel amorphous-silicon detectors, has been studied. The system is meant to be capable of three main functions: radiographs for three-dimensional (3D) patient set-up, cone-beam CT and real-time tumour/marker tracking. The goal of the current study is to determine whether one source/panel pair is sufficient for real-time tumour/marker tracking and, if two are needed, the optimal position of each relative to other components and the isocentre. A single gantry-mounted source/imager pair is certainly capable of the first two of the three functions listed above and may also be useful for the third, if combined with prior knowledge of the target's trajectory. This would be necessary because only motion in two dimensions is visible with a single imager/source system. However, with previously collected information about the trajectory, the third coordinate may be derived from the other two with sufficient accuracy to facilitate tracking. This deduction of the third coordinate can only be made if the 3D tumour/marker trajectory is consistent from fraction to fraction. The feasibility of tumour tracking with one source/imager pair has been theoretically examined here using measured lung marker trajectory data for seven patients from multiple treatment fractions. The patients' selection criteria include minimum mean amplitudes of the tumour motions greater than 1 cm peak-to-peak. The marker trajectory for each patient was modelled using the first fraction data. Then for the rest of the data, marker positions were derived from the imager projections at various gantry angles and compared with the measured tumour positions. Our results show that, due to the three dimensionality and irregular trajectory characteristics of tumour motion, on a fraction-to-fraction basis, a 'monoscopic' system (single source/imager) is inadequate for consistent real-time tumour tracking, even with prior knowledge. We found that, among the seven patients studied with peak-to-peak marker motion greater than 1 cm, five cases have mean localization errors greater than 2 mm and two have mean errors greater than 3 mm. Because of this uncertainty associated with a monoscopic system, two source/imager pairs are necessary for robust 3D target localization. Dual orthogonal x-ray source/imager pairs mounted on the linac gantry are chosen for the IRIS. We further studied the placement of the x-ray sources/panel based on the geometric specifications of the Varian 21EX Clinac. The best configuration minimizes the localization error while maintaining a large field of view and avoiding collisions with the floor/ceiling or couch.

Global Real-Time Nowcasting of Ionosphere with Giro-Driven Assimilative IRI

NASA Astrophysics Data System (ADS)

Galkin, I. A.; Reinisch, B. W.; Huang, X. A.; Vesnin, A.; Bilitza, D.; Song, P.

2014-12-01

Real-time prediction of the ionosphere beyond its quiet-time median behavior has proved to be a great challenge: low-latency sensor data streams are scarce, and early comparisons conducted within the CEDAR ETI Assessment framework showed that, on average, the assimilative physics-based models perform on par with the long-term empirical predictions. This rather surprising result led to the formation of the Real-Time Task Force of the International Reference Ionosphere (IRI) science team in 2011, with a simple objective to develop a method for correcting the IRI long-term climatology definitions on the fly, i.e., in near real-time, using suitable observations. Three years later, a pilot version of the IRI-based Real-Time Assimilative Model "IRTAM" started its continuous operations at the Global Ionosphere Radio Observatory (GIRO) Data Center, using online feeds from the ionosondes contributing data to GIRO. The IRTAM version 0.1B builds and publishes every 15-minutes an updated "global weather" map of the peak density and height in the ionosphere, as well as a map of deviations from the classic IRI climate. Incidentally, the IRTAM verification and validation efforts shed light on the forecasting capabilities of the assimilative IRI extension, even though it has not yet involved external activity indicators. At the core of the assimilative computations, a Non-linear Error Compensation Technique for Associative Restoration (NECTAR) seeks agreement between IRI prediction and the 24-hour history of latest observations at GIRO sensor sites to produce the one map frame. The NECTAR first evaluates the diurnal harmonics of the observed deviations from the IRI climatology at each GIRO site to then independently compute the spatial maps for each diurnal harmonic. Thus obtained "corrective" coefficients of the spatial-diurnal expansion are added to the original IRI set of coefficients to obtain the IRTAM specification. We are intrigued by the IRTAM capability to glean ionospheric dynamics over no-data areas, and the potential for short-term forecasting.

How Big Data Informs Us About Cataract Surgery: The LXXII Edward Jackson Memorial Lecture.

PubMed

Coleman, Anne Louise

2015-12-01

To characterize the role of Big Data in evaluating quality of care in ophthalmology, to highlight opportunities for studying quality improvement using data available in the American Academy of Ophthalmology Intelligent Research in Sight (IRIS) Registry, and to show how Big Data informs us about rare events such as endophthalmitis after cataract surgery. Review of published studies, analysis of public-use Medicare claims files from 2010 to 2013, and analysis of IRIS Registry from 2013 to 2014. Statistical analysis of observational data. The overall rate of endophthalmitis after cataract surgery was 0.14% in 216 703 individuals in the Medicare database. In the IRIS Registry the endophthalmitis rate after cataract surgery was 0.08% among 511 182 individuals. Endophthalmitis rates tended to be higher in eyes with combined cataract surgery and anterior vitrectomy (P = .051), although only 0.08% of eyes had this combined procedure. Visual acuity (VA) in the IRIS Registry in eyes with and without postoperative endophthalmitis measured 1-7 days postoperatively were logMAR 0.58 (standard deviation [SD]: 0.84) (approximately Snellen acuity of 20/80) and logMAR 0.31 (SD: 0.34) (approximately Snellen acuity of 20/40), respectively. In 33 547 eyes with postoperative VA after cataract surgery, 18.3% had 1-month-postoperative VA worse than 20/40. Big Data drawing on Medicare claims and IRIS Registry records can help identify additional areas for quality improvement, such as in the 18.3% of eyes in the IRIS Registry having 1-month-postoperative VA worse than 20/40. The ability to track patient outcomes in Big Data sets provides opportunities for further research on rare complications such as postoperative endophthalmitis and outcomes from uncommon procedures such as cataract surgery combined with anterior vitrectomy. But privacy and data-security concerns associated with Big Data should not be taken lightly. Copyright © 2015 Elsevier Inc. All rights reserved.

Cyberinfrastructure at IRIS: Challenges and Solutions Providing Integrated Data Access to EarthScope and Other Earth Science Data

NASA Astrophysics Data System (ADS)

Ahern, T. K.; Barga, R.; Casey, R.; Kamb, L.; Parastatidis, S.; Stromme, S.; Weertman, B. T.

2008-12-01

While mature methods of accessing seismic data from the IRIS DMC have existed for decades, the demands for improved interdisciplinary data integration call for new approaches. Talented software teams at the IRIS DMC, UNAVCO and the ICDP in Germany, have been developing web services for all EarthScope data including data from USArray, PBO and SAFOD. These web services are based upon SOAP and WSDL. The EarthScope Data Portal was the first external system to access data holdings from the IRIS DMC using Web Services. EarthScope will also draw more heavily upon products to aid in cross-disciplinary data reuse. A Product Management System called SPADE allows archive of and access to heterogeneous data products, presented as XML documents, at the IRIS DMC. Searchable metadata are extracted from the XML and enable powerful searches for products from EarthScope and other data sources. IRIS is teaming with the External Research Group at Microsoft Research to leverage a powerful Scientific Workflow Engine (Trident) and interact with the web services developed at centers such as IRIS to enable access to data services as well as computational services. We believe that this approach will allow web- based control of workflows and the invocation of computational services that transform data. This capability will greatly improve access to data across scientific disciplines. This presentation will review some of the traditional access tools as well as many of the newer approaches that use web services, scientific workflow to improve interdisciplinary data access.

Toxoplasmosis-associated IRIS involving the CNS: a case report with longitudinal analysis of T cell subsets.

PubMed

Rb-Silva, Rita; Nobrega, Claudia; Reiriz, Eugénia; Almeida, Soraia; Sarmento-Castro, Rui; Correia-Neves, Margarida; Horta, Ana

2017-01-13

HIV-infected patients may present an unforeseen clinical worsening after initiating antiretroviral therapy known as immune reconstitution inflammatory syndrome (IRIS). This syndrome is characterized by a heightened inflammatory response toward infectious or non-infectious triggers, and it may affect different organs. Diagnosis of IRIS involving the central nervous system (CNS-IRIS) is challenging due to heterogeneous manifestations, absence of biomarkers to identify this condition, risk of long-term sequelae and high mortality. Hence, a deeper knowledge of CNS-IRIS pathogenesis is needed. A 37-year-old man was diagnosed with AIDS and cerebral toxoplasmosis. Anti-toxoplasma treatment was initiated immediately, followed by active antiretroviral therapy (HAART) 1 month later. At 2 months of HAART, he presented with progressive hyposensitivity of the right lower limb associated with brain and dorsal spinal cord lesions, compatible with paradoxical toxoplasmosis-associated CNS-IRIS, a condition with very few reported cases. A stereotactic biopsy was planned but was postponed based on its inherent risks. Patient showed clinical improvement with no requirement of corticosteroid therapy. Routine laboratorial analysis was complemented with longitudinal evaluation of blood T cell subsets at 0, 1, 2, 3 and 6 months upon HAART initiation. A control group composed by 9 HIV-infected patients from the same hospital but with no IRIS was analysed for comparison. The CNS-IRIS patient showed lower percentage of memory CD4 + T cells and higher percentage of activated CD4 + T cells at HAART initiation. The percentage of memory CD4 + T cells drastically increased at 1 month after HAART initiation and became higher in comparison to the control group until clinical recovery onset; the percentage of memory CD8 + T cells was consistently lower throughout follow-up. Interestingly, the percentage of regulatory T cells (Treg) on the CNS-IRIS patient reached a minimum around 1 month before symptoms onset. Although both stereotactic biopsies and steroid therapy might be of use in CNS-IRIS cases and should be considered for these patients, they might be unnecessary to achieve clinical improvement as shown in this case. Immunological characterization of more CNS-IRIS cases is essential to shed some light on the pathogenesis of this condition.

Determination of irinotecan and its metabolite SN-38 in dried blood spots using high-performance liquid-chromatography with fluorescence detection.

PubMed

Hahn, Roberta Z; Arnhold, Priscila C; Andriguetti, Natália B; Schneider, Anelise; Klück, Helena M; Dos Reis, Simone L; Bastiani, Marcos Frank; Kael, Igor; da Silva, Anne Caroline Cezimbra; Schwartsmann, Gilberto; Antunes, Marina V; Linden, Rafael

2018-02-20

Irinotecan (IRI) is an antineoplastic drug widely used for the treatment of colorectal and advanced pancreatic cancer. Despite its clinical utility, the clinical use of IRI is associated with potentially severe hematopoietic and gastrointestinal toxicities. The quantification of IRI and its active metabolite SN-38 in dried blood spots (DBS) may be an alternative to individualize the drug dose through a minimally invasive and easy collection method. The aim of this study was to develop and validate a simple and fast HPLC-FL assay for simultaneous IRI and SN-38 measurement in DBS, with adequate analytical performance for clinical use. The method employs liquid extraction of one 8mm disk of whole blood, followed by separation in a reversed phase Eclipse Plus C8 column (150×4.6mm, 5μm). Detection was performed with a fluorescence detector, with excitation wavelength of 370 and emission of 420 for IRI and 540nm for SN-38 and internal standard (camptothecin). Total analytical run time was 17min. Mobile phase was a mixture of 0.1M phosphate buffer pH 4.0 and acetonitrile (80:20, v/v), at 1mLmin -1 . The assay was linear in the range 10-3,000ngmL -1 and from 0.5 to 300ngmL -1 for IRI and SN-38, respectively. Precision assays presented CV% of 2.71-5.65 and 2.15-10.07 for IRI and SN-38, respectively, and accuracy in the range of 94.26-100.93 and 94.24-99.33%. IRI and SN-38 were stable at 25 and 42°C for 14days in DBS samples. The method was applied to DBS samples obtained from fingerpicks from 19 volunteers receiving IRI in single or combined chemotherapy regimens, collected 1 and 24h after beginning of the infusion. The estimated plasma concentration of IRI and SN-38 in sample collected 1h after star of infusion had 16 of 19 values within the ±20% range of the measured plasma concentrations. On the other hand, predictions of IRI and SN-38 plasma concentrations from DBS measurements obtained 24h after the beginning of the infusion were poor. AUC of IRI that was calculated using plasma and DBS-estimated concentrations, with a high correlation (r=0.918). The method presented suitable characteristics for the clinical use. However, translation of IRI and SN-38 DBS to plasma concentrations is challenging due to the compound's variable plasma/blood partition. Copyright © 2017 Elsevier B.V. All rights reserved.

Assessing for domestic violence in sexual health environments: a qualitative study.

PubMed

Horwood, Jeremy; Morden, Andrew; Bailey, Jayne E; Pathak, Neha; Feder, Gene

2018-03-01

Domestic violence and abuse (DVA) is a major clinical challenge and public health issue. Sexual health services are an important potential site of DVA intervention. The Assessing for Domestic Violence in Sexual Health Environments (ADViSE) intervention aimed to improve identification and management of DVA in sexual healthcare settings and is a modified version of the Identification and Referral to Improve Safety (IRIS) general practice programme. Our qualitative evaluation aimed to explore the experiences of staff participating in an IRIS ADViSE pilot. Interviews were conducted with 17 sexual health clinic staff and DVA advocate workers. Interviews were audio recorded, transcribed, anonymised and analysed thematically. Staff prioritised enquiring about DVA and tailored their style of enquiry to the perceived characteristics of patients, current workload and individual clinical judgements. Responding to disclosures of abuse was divided between perceived low-risk cases (with quick onwards referral) and high-risk cases (requiring deployment of institution safeguarding procedures), which were viewed as time consuming and could create tensions with patients. Ongoing training and feedback, commissioner recognition, adequate service-level agreements and reimbursements are required to ensure sustainability and wider implementation of IRIS ADViSE. Challenges of delivering and sustaining IRIS ADViSE included the varied styles of enquiry, as well as tensions and additional time pressure arising from disclosure of abuse. These can be overcome by modifying initial training, providing regular updates and stronger recognition (and resources) at policy and commissioning levels. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Infrared Imagery of Shuttle (IRIS). Task 2, summary report

NASA Technical Reports Server (NTRS)

Chocol, C. J.

1978-01-01

End-to-end tests of a 16 element indium antimonide sensor array and 10 channels of associated electronic signal processing were completed. Quantitative data were gathered on system responsivity, frequency response, noise, stray capacitance effects, and sensor paralleling. These tests verify that the temperature accuracies, predicted in the Task 1 study, can be obtained with a very carefully designed electro-optical flight system. Pre-flight and inflight calibration of a high quality are mandatory to obtain these accuracies. Also, optical crosstalk in the array-dewar assembly must be carefully eliminated by its design. Tests of the scaled up tracking system reticle also demonstrate that the predicted tracking system accuracies can be met in the flight system. In addition, improvements in the reticle pattern and electronics are possible, which will reduce the complexity of the flight system and increase tracking accuracy.

High-Speed Noninvasive Eye-Tracking System

NASA Technical Reports Server (NTRS)

Talukder, Ashit; LaBaw, Clayton; Michael-Morookian, John; Monacos, Steve; Serviss, Orin

2007-01-01

The figure schematically depicts a system of electronic hardware and software that noninvasively tracks the direction of a person s gaze in real time. Like prior commercial noninvasive eye-tracking systems, this system is based on (1) illumination of an eye by a low-power infrared light-emitting diode (LED); (2) acquisition of video images of the pupil, iris, and cornea in the reflected infrared light; (3) digitization of the images; and (4) processing the digital image data to determine the direction of gaze from the centroids of the pupil and cornea in the images. Relative to the prior commercial systems, the present system operates at much higher speed and thereby offers enhanced capability for applications that involve human-computer interactions, including typing and computer command and control by handicapped individuals,and eye-based diagnosis of physiological disorders that affect gaze responses.

Developing virtual REU cohorts: Reflections from the IRIS Undergraduate Internship Program

NASA Astrophysics Data System (ADS)

Hubenthal, M.; Taber, J.; Aster, R.; Frassetto, A.

2007-12-01

Beginning in 2006, the IRIS Education and Outreach program received funding from the National Science Foundation (EAR-0453427) to explore a novel approach to the traditional Research Experience for Undergraduates (REU) model. This model blends the spirit of an REU program, which traditionally hosts participants in one location with successful prior IRIS experience hosting students at widely separated institutions to participate in summer research. A unique feature the IRIS Undergraduate Internship Program is that throughout the summer, interns form and sustain a virtual community, offering assistance, sharing ideas, asking questions, and relaying life experiences while conducting their research at diverse institutions. Key to IRIS's REU model is a combination of: one-on-one mentoring by researchers at IRIS institutions across the US, developing a strong unity among interns through both face-to-face and on-line interactions, participation of an IRIS REU alumni mentor to provide both group and intern-specific guidance developing interns' abilities to self-evaluate and work independently, through carefully designed web-based tools, and increasing interns' awareness of the IRIS and broader Earth Science community; demonstrating the role they will play in this larger community. Virtual interaction is facilitated by 1) bringing students together for face-to-face contact, through a week long orientation held annually at the IRIS PASSCAL Instrument Center on the campus of the New Mexico Institute of Mining and Technology, and 2) the community enabling web infrastructure at http://www.iris.edu/internship/. During the orientation students engage in classes in geophysics basics, career preparation, as well as training to communicate virtually. Our experiences and evaluations from the 2006 and 2007 field seasons have:shown the increasing demand for electronic advertising of REU programs, provided support for several assumptions of the model including the key role of both the orientation week and the alumni mentor, revealed the important role of blogs and discussion forums in the mentoring and self-reflection process, as well as additional technical enhancements to improve the virtual cohort, produced concrete examples of the model applied at its best, and helped the program identify challenges the model faces, e.g communicating during remote fieldwork and sustaining intern's attention and participation in the virtual community.

PHyTIR - A Prototype Thermal Infrared Radiometer

NASA Technical Reports Server (NTRS)

Jau, Bruno M.; Hook, Simon J.; Johnson, William R.; Foote, Marc C.; Paine, Christopher G.; Pannell, Zack W.; Smythe, Robert F.; Kuan, Gary M.; Jakoboski, Julie K.; Eng, Bjorn T.

2013-01-01

This paper describes the PHyTIR (Prototype HyspIRI Thermal Infrared Radiometer) instrument, which is the engineering model for the proposed HyspIRI (Hyperspectral Infrared Imager) earth observing instrument. The HyspIRI mission would be comprised of the HyspIRI TIR (Thermal Infrared Imager), and a VSWIR (Visible Short-Wave Infra-Red Imaging Spectrometer). Both instruments would be used to address key science questions related to the earth's carbon cycle, ecosystems, climate, and solid earth properties. Data gathering of volcanic activities, earthquakes, wildfires, water use and availability, urbanization, and land surface compositions and changes, would aid the predictions and evaluations of such events and the impact they create. Even though the proposed technology for the HyspIRI imager is mature, the PHyTIR prototype is needed to advance the technology levels for several of the instrument's key components, and to reduce risks, in particular to validate 1) the higher sensitivity, spatial resolution, and higher throughput required for this focal plane array, 2) the pointing accuracy, 2) the characteristics of several spectral channels, and 4) the use of ambient temperature optics. The PHyTIR telescope consists of the focal plane assembly that is housed within a cold housing located inside a vacuum enclosure; all mounted to a bulkhead, and an optical train that consists of 3 powered mirrors; extending to both sides of the bulkhead. A yoke connects the telescope to a scan mirror. The rotating mirror enables to scan- a large track on the ground. This structure is supported by kinematic mounts, linking the telescope assembly to a base plate that would also become the spacecraft interface for HyspIRI. The focal plane's cooling units are also mounted to the base plate, as is an overall enclosure that has two viewing ports with large exterior baffles, shielding the focal plane from incoming stray light. PHyTIR's electronics is distributed inside and near the vacuum enclosure, and in a nearby rack. The data acquisition technique would be to take measurements over a 51deg wide swath in the cross spacecraft velocity direction, which is brought into view through the rotating scan mirror. A landscape mosaic thus can be assembled by overlaying rows of measurements. The paper briefly outlines the proposed HyspIRI mission and its data acquisition technique; it then describes the prototype PHyTIR instrument.

Design and performance of a cryogenic iris aperture mechanism

NASA Astrophysics Data System (ADS)

de Jonge, C.; Laauwen, W. M.; de Vries, E. A.; Smit, H. P.; Detrain, A.; Eggens, M. J.; Ferrari, L.; Dieleman, P.

2014-07-01

A cryogenic iris mechanism is under development as part of the ground calibration source for the SAFARI instrument. The iris mechanism is a variable aperture used as an optical shutter to fine-tune and modulate the absolute power output of the calibration source. It has 4 stainless steel blades that create a near-circular aperture in every position. The operating temperature is 4.5 Kelvin to provide a negligible background to the SAFARI detectors, and `hot spots' above 9K should be prevented. Cryogenic testing proved that the iris works at 4K. It can be used in a broad range of cryogenic optical instruments where optical throughput needs to be controlled. Challenges in the design include the low cooling power available (5mW) and low friction at cryogenic temperatures. The actuator is an `arc-type' rotary voice-coil motor. The use of flexural pivots creates a mono-stable mechanism with a resonance frequency at 26Hz. Accurate and fast position control with disturbance rejection is managed by a PID servo loop using a hall-sensor as input. At 4 Kelvin, the frequency is limited to 4Hz to avoid excess dissipation and heating. In this paper, the design and performance of the iris are discussed. The design was optimized using a thermal, magnetic and mechanical model made with COMSOL Finite Element Analysis software. The dynamical and state-space modeling of the mechanism and the concept of the electrical control are presented. The performance of the iris show good agreement to the analytical and COMSOL modeling.

Cardiac Ischemia/Reperfusion Injury: The Beneficial Effects of Exercise.

PubMed

Borges, Juliana Pereira; da Silva Verdoorn, Karine

2017-01-01

Cardiac ischemia reperfusion injury (IRI) occurs when the myocardium is revascularized after an episode of limited or absent blood supply. Many changes, including free radical production, calcium overload, protease activation, altered membrane lipids and leukocyte activation, contribute to IRI-induced myocardium damage. Aerobic exercise is the only countermeasure against IRI that can be sustained on a regular basis in clinical practice. Interestingly, both short-term (3-5 days) and long-term (several weeks) exercise increase myocardial tolerance, reduce infarct size area and arrhythmias induced by IRI. Exercise protects the heart against IRI in a biphasic manner. The early phase of cardioprotection occurs between 30 min and 3 h following an acute exercise bout, whilst the late phase is achieved within 24 h after the exercise bout and persists for several days. As for the exercise intensity, although controversial data exists, it is feasible that the amount of cardioprotection is proportional to exercise intensity and only achieved above a critical threshold. It is known that aerobic exercise produces a cardioprotective phenotype, however the mechanisms responsible for this phenomenon remain unclear. Apparently, aerobic exercise-induced preconditioning is dependent on several factors that work together to protect the heart. Altered nitric oxide (NO) signaling, increased levels of heat shock proteins (HSPs), enhanced function of ATP-sensitive potassium channels, increased activation of opioids system, and enhanced antioxidant capacity may contribute to exercise-induced cardioprotection. Much has been discovered from animal models involving exercise-induced cardioprotection against cardiac IRI, however translating these findings to clinical practice still represents the major challenge in this field.

Accuracy of student performance while reading leveled books rated at their instructional level by a reading inventory.

PubMed

Burns, Matthew K; Pulles, Sandra M; Maki, Kathrin E; Kanive, Rebecca; Hodgson, Jennifer; Helman, Lori A; McComas, Jennifer J; Preast, June L

2015-12-01

Identifying a student's instructional level is necessary to ensure that students are appropriately challenged in reading. Informal reading inventories (IRIs) purport to assess the highest reading level at which a student can accurately decode and comprehend text. However, the use of IRIs in determining a student's instructional level has been questioned because of a lack of research. The current study examined the percentage of words read correctly with 64 second- and third-grade students while reading from texts at their instructional level as determined by an IRI. Students read for 1 min from three leveled texts that corresponded to their instructional level as measured by an IRI, and the percentage of words read correctly was recorded. The percentage read correctly correlated across the three books from r=.47 to r=.68 and instructional level categories correlated from tau=.59 to tau=.65. Percent agreement calculations showed that the categorical scores (frustration, instructional, and independent) for the three readings agreed approximately 67% to 70% of the time, which resulted in a kappa estimate of less than .50. Kappa coefficients of .70 are considered strong indicators of agreement. Moreover, more than half of the students with the lowest reading skills read at a frustration level when attempting to read books rated at their instructional level by an IRI. The current study questions how reliably and accurately IRIs identify students' instructional level for reading. Copyright © 2015 Society for the Study of School Psychology. Published by Elsevier Ltd. All rights reserved.

Six years after the NRC review of EPA's Draft IRIS Toxicological Review of Formaldehyde: Regulatory implications of new science in evaluating formaldehyde leukemogenicity.

PubMed

Mundt, Kenneth A; Gentry, P Robinan; Dell, Linda D; Rodricks, Joseph V; Boffetta, Paolo

2018-02-01

Shortly after the International Agency for Research on Cancer (IARC) determined that formaldehyde causes leukemia, the United States Environmental Protection Agency (EPA) released its Draft IRIS Toxicological Review of Formaldehyde ("Draft IRIS Assessment"), also concluding that formaldehyde causes leukemia. Peer review of the Draft IRIS Assessment by a National Academy of Science committee noted that "causal determinations are not supported by the narrative provided in the draft" (NRC 2011). They offered recommendations for improving the Draft IRIS assessment and identified several important research gaps. Over the six years since the NRC peer review, significant new science has been published. We identify and summarize key recommendations made by NRC and map them to this new science, including extended analysis of epidemiological studies, updates of earlier occupational cohort studies, toxicological experiments using a sensitive mouse strain, mechanistic studies examining the role of exogenous versus endogenous formaldehyde in bone marrow, and several critical reviews. With few exceptions, new findings are consistently negative, and integration of all available evidence challenges the earlier conclusions that formaldehyde causes leukemia. Given formaldehyde's commercial importance, environmental ubiquity and endogenous production, accurate hazard classification and risk evaluation of whether exposure to formaldehyde from occupational, residential and consumer products causes leukemia are critical. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Immune Reconstitution Reactions in Human Immunodeficiency Virus–Negative Patients

PubMed Central

Scharschmidt, Tiffany C.; Amerson, Erin H.; Rosenberg, Oren S.; Jacobs, Richard A.; McCalmont, Timothy H.; Shinkai, Kanade

2013-01-01

Background Immune reconstitution inflammatory syndrome (IRIS) is a phenomenon initially described in patients with human immunodeficiency virus. Upon initiation of combination antiretroviral therapy, recovery of cellular immunity triggers inflammation to a preexisting infection or antigen that causes paradoxical worsening of clinical disease. A similar phenomenon can occur in human immunodeficiency virus–negative patients, including pregnant women, neutropenic hosts, solidorgan or stem cell transplant recipients, and patients receiving tumor necrosis factor inhibitors. Observations We report a case of leprosy unmasking and downgrading reaction after stem cell transplantation that highlights some of the challenges inherent to the diagnosis of IRIS, especially in patients without human immunodeficiency virus infection, as well as review the spectrum of previously reported cases of IRIS reactions in this population. Conclusions The mechanism of immune reconstitution reactions is complex and variable, depending on the underlying antigen and the mechanism of immunosuppression or shift in immune status. Use of the term IRIS can aid our recognition of an important phenomenon that occurs in the setting of immunosuppression or shifts in immunity but should not deter us from thinking critically about the distinct processes that underlie this heterogeneous group of conditions. PMID:23324760

Ice and anti-nucleating activities of an ice-binding protein from the annual grass, Brachypodium distachyon.

PubMed

Bredow, Melissa; Tomalty, Heather E; Smith, Lindsay; Walker, Virginia K

2018-05-01

Plants exposed to sub-zero temperatures face unique challenges that threaten their survival. The growth of ice crystals in the extracellular space can cause cellular dehydration, plasma membrane rupture and eventual cell death. Additionally, some pathogenic bacteria cause tissue damage by initiating ice crystal growth at high sub-zero temperatures through the use of ice-nucleating proteins (INPs), presumably to access nutrients from lysed cells. An annual species of brome grass, Brachypodium distachyon (Bd), produces an ice-binding protein (IBP) that shapes ice with a modest depression of the freezing point (~0.1 °C at 1 mg/mL), but high ice-recrystallization inhibition (IRI) activity, allowing ice crystals to remain small at near melting temperatures. This IBP, known as BdIRI, is unlike other characterized IBPs with a single ice-binding face, as mutational analysis indicates that BdIRI adsorbs to ice on two faces. BdIRI also dramatically attenuates the nucleation of ice by bacterial INPs (up to -2.26 °C). This 'anti-nucleating' activity is significantly higher than previously documented for any IBP. © 2016 John Wiley & Sons Ltd.

Ten years of intraoperative floppy iris syndrome in the era of α-blockers

PubMed Central

Mohamad Al-Ali, Badereddin; Radmayr, Christian; Weber, Maria; Horninger, Wolfgang; Findl, Oliver; Plas, Eugen

2017-01-01

Introduction The use of alpha-1 receptor antagonists in the treatment of benign prostatic hyperplasia (BPH) has created a problem in ophthalmic surgery, the so-called intraoperative floppy iris syndrome (IFIS). This consists of a billowing iris, insufficient pupillary dilation with progressive intraoperative miosis, and protrusion of iris tissue through the tunnel and side port incision that are made for access to the anterior chamber during surgery. IFIS presents particular difficulties in cataract surgery which is carried out through the pupil with manipulations in the immediate vicinity of the iris. The complications range from poor visibility of the operative field to iris damage with the surgical instruments and to rupture of the posterior capsule, with loss of lens material into the vitreous body. Material and methods A comprehensive literature review was performed using MEDLINE with MeSH terms and keywords ‘benign prostatic hyperplasia’, ‘intraoperative floppy iris syndrome’, ‘adrenergic alpha-antagonist’ and ‘cataract surgery’. In addition, reference lists from identified publications were reviewed to identify reports and studies of interest from 2001 to 2017. Results The A total of 95% of experienced ophthalmologic surgeons reported that systematic treatment with tamsulosin represents a challenging surgical condition increasing the risk of complications. Alpha-blockers are commonly prescribed, with 1,079,505 packages of tamsulosin prescribed each month in 2014 in Austria. Dose modification may be one way to reduce the risk of IFIS. A lower incidence of IFIS was reported in patients on tamsulosin in Japan, but the recommended dosage was lower than that used in Europe and the US (0.2 mg vs. 0.4 mg). Conclusions We showed that not all patients taking tamsulosin experience IFIS. Moreover, larger investigations with a prospective design are needed, including studies to monitor the pre- and post-therapeutic ophthalmologic changes under tamsulosin, as well as urodynamic improvements resulting from this therapy. PMID:29732214

Development of Camera Model and Geometric Calibration/validation of Xsat IRIS Imagery

NASA Astrophysics Data System (ADS)

Kwoh, L. K.; Huang, X.; Tan, W. J.

2012-07-01

XSAT, launched on 20 April 2011, is the first micro-satellite designed and built in Singapore. It orbits the Earth at altitude of 822 km in a sun synchronous orbit. The satellite carries a multispectral camera IRIS with three spectral bands - 0.52~0.60 mm for Green, 0.63~0.69 mm for Red and 0.76~0.89 mm for NIR at 12 m resolution. In the design of IRIS camera, the three bands were acquired by three lines of CCDs (NIR, Red and Green). These CCDs were physically separated in the focal plane and their first pixels not absolutely aligned. The micro-satellite platform was also not stable enough to allow for co-registration of the 3 bands with simple linear transformation. In the camera model developed, this platform stability was compensated with 3rd to 4th order polynomials for the satellite's roll, pitch and yaw attitude angles. With the camera model, the camera parameters such as the band to band separations, the alignment of the CCDs relative to each other, as well as the focal length of the camera can be validated or calibrated. The results of calibration with more than 20 images showed that the band to band along-track separation agreed well with the pre-flight values provided by the vendor (0.093° and 0.046° for the NIR vs red and for green vs red CCDs respectively). The cross-track alignments were 0.05 pixel and 5.9 pixel for the NIR vs red and green vs red CCDs respectively. The focal length was found to be shorter by about 0.8%. This was attributed to the lower operating temperature which XSAT is currently operating. With the calibrated parameters and the camera model, a geometric level 1 multispectral image with RPCs can be generated and if required, orthorectified imagery can also be produced.

SeisCode: A seismological software repository for discovery and collaboration

NASA Astrophysics Data System (ADS)

Trabant, C.; Reyes, C. G.; Clark, A.; Karstens, R.

2012-12-01

SeisCode is a community repository for software used in seismological and related fields. The repository is intended to increase discoverability of such software and to provide a long-term home for software projects. Other places exist where seismological software may be found, but none meet the requirements necessary for an always current, easy to search, well documented, and citable resource for projects. Organizations such as IRIS, ORFEUS, and the USGS have websites with lists of available or contributed seismological software. Since the authors themselves do often not maintain these lists, the documentation often consists of a sentence or paragraph, and the available software may be outdated. Repositories such as GoogleCode and SourceForge, which are directly maintained by the authors, provide version control and issue tracking but do not provide a unified way of locating geophysical software scattered in and among countless unrelated projects. Additionally, projects are hosted at language-specific sites such as Mathworks and PyPI, in FTP directories, and in websites strewn across the Web. Search engines are only partially effective discovery tools, as the desired software is often hidden deep within the results. SeisCode provides software authors a place to present their software, codes, scripts, tutorials, and examples to the seismological community. Authors can choose their own level of involvement. At one end of the spectrum, the author might simply create a web page that points to an existing site. At the other extreme, an author may choose to leverage the many tools provided by SeisCode, such as a source code management tool with integrated issue tracking, forums, news feeds, downloads, wikis, and more. For software development projects with multiple authors, SeisCode can also be used as a central site for collaboration. SeisCode provides the community with an easy way to discover software, while providing authors a way to build a community around their software packages. IRIS invites the seismological community to browse and to submit projects to https://seiscode.iris.washington.edu/

Onboard Science and Applications Algorithm for Hyperspectral Data Reduction

NASA Technical Reports Server (NTRS)

Chien, Steve A.; Davies, Ashley G.; Silverman, Dorothy; Mandl, Daniel

2012-01-01

An onboard processing mission concept is under development for a possible Direct Broadcast capability for the HyspIRI mission, a Hyperspectral remote sensing mission under consideration for launch in the next decade. The concept would intelligently spectrally and spatially subsample the data as well as generate science products onboard to enable return of key rapid response science and applications information despite limited downlink bandwidth. This rapid data delivery concept focuses on wildfires and volcanoes as primary applications, but also has applications to vegetation, coastal flooding, dust, and snow/ice applications. Operationally, the HyspIRI team would define a set of spatial regions of interest where specific algorithms would be executed. For example, known coastal areas would have certain products or bands downlinked, ocean areas might have other bands downlinked, and during fire seasons other areas would be processed for active fire detections. Ground operations would automatically generate the mission plans specifying the highest priority tasks executable within onboard computation, setup, and data downlink constraints. The spectral bands of the TIR (thermal infrared) instrument can accurately detect the thermal signature of fires and send down alerts, as well as the thermal and VSWIR (visible to short-wave infrared) data corresponding to the active fires. Active volcanism also produces a distinctive thermal signature that can be detected onboard to enable spatial subsampling. Onboard algorithms and ground-based algorithms suitable for onboard deployment are mature. On HyspIRI, the algorithm would perform a table-driven temperature inversion from several spectral TIR bands, and then trigger downlink of the entire spectrum for each of the hot pixels identified. Ocean and coastal applications include sea surface temperature (using a small spectral subset of TIR data, but requiring considerable ancillary data), and ocean color applications to track biological activity such as harmful algal blooms. Measuring surface water extent to track flooding is another rapid response product leveraging VSWIR spectral information.

Correlation peak analysis applied to a sequence of images using two different filters for eye tracking model

NASA Astrophysics Data System (ADS)

Patrón, Verónica A.; Álvarez Borrego, Josué; Coronel Beltrán, Ángel

2015-09-01

Eye tracking has many useful applications that range from biometrics to face recognition and human-computer interaction. The analysis of the characteristics of the eyes has become one of the methods to accomplish the location of the eyes and the tracking of the point of gaze. Characteristics such as the contrast between the iris and the sclera, the shape, and distribution of colors and dark/light zones in the area are the starting point for these analyses. In this work, the focus will be on the contrast between the iris and the sclera, performing a correlation in the frequency domain. The images are acquired with an ordinary camera, which with were taken images of thirty-one volunteers. The reference image is an image of the subjects looking to a point in front of them at 0° angle. Then sequences of images are taken with the subject looking at different angles. These images are processed in MATLAB, obtaining the maximum correlation peak for each image, using two different filters. Each filter were analyzed and then one was selected, which is the filter that gives the best performance in terms of the utility of the data, which is displayed in graphs that shows the decay of the correlation peak as the eye moves progressively at different angle. This data will be used to obtain a mathematical model or function that establishes a relationship between the angle of vision (AOV) and the maximum correlation peak (MCP). This model will be tested using different input images from other subject not contained in the initial database, being able to predict angle of vision using the maximum correlation peak data.

Remote Sensing of Ionosphere by IONOLAB Group

NASA Astrophysics Data System (ADS)

Arikan, Feza

2016-07-01

Ionosphere is a temporally and spatially varying, dispersive, anisotropic and inhomogeneous medium that is characterized primarily by its electron density distribution. Electron density is a complex function of spatial and temporal variations of solar, geomagnetic, and seismic activities. Ionosphere is the main source of error for navigation and positioning systems and satellite communication. Therefore, characterization and constant monitoring of variability of the ionosphere is of utmost importance for the performance improvement of these systems. Since ionospheric electron density is not a directly measurable quantity, an important derivable parameter is the Total Electron Content (TEC), which is used widely to characterize the ionosphere. TEC is proportional to the total number of electrons on a line crossing the atmosphere. IONOLAB is a research group is formed by Hacettepe University, Bilkent University and Kastamonu University, Turkey gathered to handle the challenges of the ionosphere using state-of-the-art remote sensing and signal processing techniques. IONOLAB group provides unique space weather services of IONOLAB-TEC, International Reference Ionosphere extended to Plasmasphere (IRI-Plas) model based IRI-Plas-MAP, IRI-Plas-STEC and Online IRI-Plas-2015 model at www.ionolab.org. IONOLAB group has been working for imaging and monitoring of ionospheric structure for the last 15 years. TEC is estimated from dual frequency GPS receivers as IONOLAB-TEC using IONOLAB-BIAS. For high spatio-temporal resolution 2-D imaging or mapping, IONOLAB-MAP algorithm is developed that uses automated Universal Kriging or Ordinary Kriging in which the experimental semivariogram is fitted to Matern Function with Particle Swarm Optimization (PSO). For 3-D imaging of ionosphere and 1-D vertical profiles of electron density, state-of-the-art IRI-Plas model based IONOLAB-CIT algorithm is developed for regional reconstruction that employs Kalman Filters for state/temporal transition. IONOLAB group contributes to remote sensing of upper atmosphere, ionosphere and plasmasphere with continuing TUBITAK projects. IONOLAB group is open to joint research and collaboration with researchers from all disciplines that investigate the challenges of ionosphere and space weather. This study is supported by TUBITAK 114E541, 115E915 and Joint TUBITAK 114E092 and AS CR 14/001 projects.

Facilitate, Collaborate, Educate: the Role of the IRIS Consortium in Supporting National and International Research in Seismology (Invited)

NASA Astrophysics Data System (ADS)

Simpson, D. W.; Beck, S. L.

2009-12-01

Over the twenty-five years since its founding in 1984, the IRIS Consortium has contributed in fundamental ways to change the practice and culture of research in seismology in the US and worldwide. From an original founding group of twenty-two U.S. academic institutions, IRIS membership has now grown to 114 U.S. Member Institutions, 20 Educational Affiliates and 103 Foreign Affiliates. With strong support from the National Science Foundation, additional resources provided by other federal agencies, close collaboration with the U.S. Geological Survey and many international partners, the technical resources of the core IRIS programs - the Global Seismographic Network (GSN), the Program for Array Seismic Studies of the Continental Lithosphere (PASSCAL), the Data Management System (DMS) and Education and Outreach - have grown to become a major national and international source of experimental data for research on earthquakes and Earth structure, and a resource to support education and outreach to the public. While the primary operational focus of the Consortium is to develop and maintain facilities for the collection of seismological data for basic research, IRIS has become much more than an instrument facility. It has become a stimulus for collaboration between academic seismological programs and a focus for their interactions with national and international partners. It has helped establish the academic community as a significant contributor to the collection of data and an active participant in global research and monitoring. As a consortium of virtually all of the Earth science research institutions in the US, IRIS has helped coordinate the academic community in the development of new initiatives, such as EarthScope, to strengthen the support for science and argue for the relevance of seismology and its use in hazard mitigation. The early IRIS pioneers had the foresight to carefully define program goals and technical standards for the IRIS facilities that have stood the test of time. Many of these technical standards for equipment and data exchange have extended to become de-facto global standards and influenced instrument development and network practices throughout the world. A governance structure for the Consortium was created that continues to encourage strong community guidance in the operation and evolution of IRIS programs. From the outset, there was a commitment to maintaining a complete archive of all IRIS data, with significant emphasis on metadata and quality control. Building on long-standing traditions of collaboration in seismological research, an explicit IRIS policy of free and open data exchange has expanded the culture of data sharing among it members, which, through example, encouragement and support, has extended to influence the data policies of numerous other organizations in seismology and the Earth sciences. The technical revolution in sensors, communications and data collection that accompanied the early development of IRIS is now available to the entire world. The challenge for IRIS and the seismology community in the decades ahead will be to encourage the implementation of these technologies, along with appropriate training and resources, to further the research community’s endeavors to understand the structure and evolution of our planet and apply that knowledge to the mitigation of earthquake hazards.

Evolution-Based Methods for Selecting Point Data for Object Localization: Applications to Computer-Assisted Surgery.

DTIC Science & Technology

1996-11-01

being evaluated in cadaver trials. Shumeet Baluja was supported by a National Science Foundation Graduate Student Fellowship and a Graduate Student...partially supported by a National Science Foundation National Challenge grant (award IRI-9422734).

Molecular Dynamics at the Interface between Ice and Poly(vinyl alcohol) and Ice Recrystallization Inhibition.

PubMed

Weng, Lindong; Stott, Shannon L; Toner, Mehmet

2018-05-01

Ice formation is a ubiquitous process that poses serious challenges for many areas. Nature has evolved a variety of different mechanisms to regulate ice formation. For example, many cold-adapted species produce antifreeze proteins (AFPs) and/or antifreeze glycoproteins (AFGPs) to inhibit ice recrystallization. Although several synthetic substitutes for AF(G)Ps have been developed, the fundamental principles of designing AF(G)P mimics are still missing. In this study, we explored the molecular dynamics of ice recrystallization inhibition (IRI) by poly(vinyl alcohol) (PVA), a well-recognized ice recrystallization inhibitor, to shed light on the otherwise hidden ice-binding mechanisms of chain polymers. Our molecular dynamics simulations revealed a stereoscopic, geometrical match between the hydroxyl groups of PVA and the water molecules of ice, and provided microscopic evidence of the adsorption of PVA to both the basal and prism faces of ice and the incorporation of short-chain PVA into the ice lattice. The length of PVA, i.e., the number of hydroxyl groups, seems to be a key factor dictating the performance of IRI, as the PVA molecule must be large enough to prevent the joining together of adjacent curvatures in the ice front. The findings in this study will help pave the path for addressing a pressing challenge in designing synthetic ice recrystallization inhibitors rationally, by enriching our mechanistic understanding of IRI process by macromolecules.

The Multicultural Challenge in Health Education.

ERIC Educational Resources Information Center

Matiella, Ana Consuelo, Ed.

This collection offers strategies for making health education culturally relevant. The volume is organized into five sections. The first section, "Foundations for Multicultural Health Education," includes chapters: (1) "Who Are the Children and How Is Their Health?" (Iris M. Tropp, Marie J. Montrose); (2) "The…

Challenges in Building Robots that Imitate People

DTIC Science & Technology

2000-01-01

pages 25 40, 1998. R. Brooks, C. Breazeal (Ferrell), R. Irie, C. Kemp, M. Marjanovic , B. Scassellati, & M. Williamson. Alternative essences of...Breazeal (Ferrell), M. Marjanovic , B. Scassellati, and M. Williamson. The Cog project: building a humanoid robot. In C. Nehaniv, editor, Computationjbr

Excimer Laser Surgery: Biometrical Iris Eye Recognition with Cyclorotational Control Eye Tracker System

PubMed Central

Pajic, Bojan; Cvejic, Zeljka; Mijatovic, Zoran; Indjin, Dragan; Mueller, Joerg

2017-01-01

A prospective comparative study assessing the importance of the intra-operative dynamic rotational tracking—especially in the treatment of astigmatisms in corneal refractive Excimer laser correction—concerning clinical outcomes is presented. The cyclotorsion from upright to supine position was measured using iris image comparison. The Group 1 of patients was additionally treated with cyclorotational control and Group 2 only with X-Y control. Significant differences were observed between the groups regarding the mean postoperative cylinder refraction (p < 0.05). The mean cyclotorsion can be calculated to 3.75° with a standard deviation of 3.1°. The total range of torsion was from −14.9° to +12.6°. Re-treatment rate was 2.2% in Group 1 and 8.2% in Group 2, which is highly significant (p < 0.01). The investigation confirms that the dynamic rotational tracking system used for LASIK results in highly predictable refraction quality with significantly less postoperative re-treatments. PMID:28587100

Management of dislocated intraocular lenses with iris suture.

PubMed

Faria, Mun Y; Ferreira, Nuno P; Canastro, Mario

2017-01-19

Subluxated or malpositioned intraocular lenses (IOLs) and inadequate capsular support is a challenge for every ophthalmic surgeon. Iris suture of an IOL seems to be an easy technique for the management of dislocated 3-piece IOL, allowing the IOL to be placed behind the iris, far from the trabecular meshwork and corneal endothelium. The purpose of this study is to assess the results of pars plana vitrectomy (PPV) and iris suture of dislocated 3-piece acrylic IOLs. In this retrospective, nonrandomized, interventional case consecutive study, of a total of 103 dislocated IOLs, 36 eyes were considered for analysis. All 36 eyes had subluxated or totally luxated 3-piece IOL and underwent iris suture at the Ophthalmology Department of Santa Maria Hospital-North Lisbon Hospital Center, Portugal, from January 2011 until November 2015. All patients underwent 3-port 23-G PPV. The optic zone of the dislocated IOL was placed anterior to the iris with the haptics behind, in the posterior chamber. Haptics were sutured to iris followed by placement of the optics behind iris plane. Postoperative measures included best-corrected visual acuity (BCVA), IOL position, intraocular pressure, pigment dispersion, clinical signs of endothelial cell loss, and development of macular edema. A total of 36 eyes of 36 patients were included. All underwent successful iris fixation of dislocated 3-piece IOL. Mean overall follow-up was 15.9 months (range 3-58 months). At presentation, 16 eyes (44.4%) had a luxated IOL and 20 eyes (55.6%) a subluxated IOL. As underlying cause, 17 eyes (47.2%) had a history of complicated cataract surgery, 5 eyes (13.9%) had a traumatic dislocation of the IOL, and 6 eyes (16.7%) had a previous vitreoretinal surgery. A total of 8 eyes (22.2%) had late spontaneous IOL dislocation after uneventful cataract surgery. The mean preoperative BCVA was 1.09 ± 0.70 logarithm of the minimal angle of resolution (logMAR) units and mean postoperative BCVA was 0.48 ± 0.58 of logMAR units. The mean visual acuity improvement was 4.08 ± 5.33 lines on the logMAR scale. In this study, every IOL was stable at the last follow-up. As late complications, macular edema occurred in 1 patient and retinal detachment occurred in 2 patients. There were no cases of endophthalmitis. Iris suture fixation of subluxated IOL is a good treatment option for eyes with dislocated IOLs, leading to long-term stability of the IOL. The advantage of this procedure is using the same IOL in a closed eye surgery. No astigmatic difference is expected as no large corneal incision is needed.

The GEON Integrated Data Viewer (IDV) and IRIS DMC Services Illustrate CyberInfrastructure Support for Seismic Data Visualization and Interpretation

NASA Astrophysics Data System (ADS)

Meertens, C.; Wier, S.; Ahern, T.; Casey, R.; Weertman, B.; Laughbon, C.

2008-12-01

UNAVCO and the IRIS DMC are data service partners for seismic visualization, particularly for hypocentral data and tomography. UNAVCO provides the GEON Integrated Data Viewer (IDV), an extension of the Unidata IDV, a free, interactive, research-level, software display and analysis tool for data in 3D (latitude, longitude, depth) and 4D (with time), located on or inside the Earth. The GEON IDV is designed to meet the challenge of investigating complex, multi-variate, time-varying, three- dimensional geoscience data in the context of new remote and shared data sources. The GEON IDV supports data access from data sources using HTTP and FTP servers, OPeNDAP servers, THREDDS catalogs, RSS feeds, and WMS (web map) servers. The IRIS DMC (Data Management System) has developed web services providing data for earthquake hypocentral data and seismic tomography model grids. These services can be called by the GEON IDV to access data at IRIS without copying files. The IRIS Earthquake Browser (IEB) is a web-based query tool for hypocentral data. The IEB combines the DMC's large database of more than 1,900,000 earthquakes with the Google Maps web interface. With the IEB you can quickly find earthquakes in any region of the globe and then import this information into the GEON Integrated Data Viewer where the hypocenters may be visualized. You can select earthquakes by location region, time, depth, and magnitude. The IEB gives the IDV a URL to the selected data. The IDV then shows the data as maps or 3D displays, with interactive control of vertical scale, area, map projection, with symbol size and color control by magnitude or depth. The IDV can show progressive time animation of, for example, aftershocks filling a source region. The IRIS Tomoserver converts seismic tomography model output grids to NetCDF for use in the IDV. The Tomoserver accepts a tomographic model file as input from a user and provides an equivalent NetCDF file as output. The service supports NA04, S3D, A1D and CUB input file formats, contributed by their respective creators. The NetCDF file is saved to a location that can be referenced with a URL on an IRIS server. The URL for the NetCDF file is provided to the user. The user can download the data from IRIS, or copy the URL into IDV directly for interpretation, and the IDV will access the data at IRIS. The Tomoserver conversion software was developed by Instrumental Software Technologies, Inc. Use cases with the GEON IDV and IRIS DMC data services will be shown.

Missing iris effect as a possible cause of muted hydrological change and high climate sensitivity in models

NASA Astrophysics Data System (ADS)

Mauritsen, T.; Stevens, B. B.

2015-12-01

Current climate models exhibit equilibrium climate sensitivities to a doubling of CO2 of 2.0-4.6 K and a weak increase of global mean precipitation. But inferences from the observational record place climate sensitivity near the lower end of the range, and indicate that models underestimate changes in certain aspects of the hydrological cycle under warming. Here we show that both these discrepancies can be explained by a controversial hypothesis of missing negative tropical feedbacks in climate models, known as the iris-effect: Expanding dry and clear regions in a warming climate yield a negative feedback as more infrared radiation can escape to space through this metaphorical opening iris. At the same time the additional infrared cooling of the atmosphere must be balanced by latent heat release thereby accelerating the hydrological cycle. Alternative suggestions of too little aerosol cooling, missing volcanic eruptions, or insufficient ocean heat uptake in models may explain a slow observed transient warming, but are not able to explain the observed enhanced hydrological cycle. We propose that a temperature-dependency of the extent to which precipitating convective clouds cluster or aggregate into larger clouds constitutes a plausible physical mechanism for the iris-effect. On a large scale, organized convective states are dryer than disorganized convection and therefore radiate more in the longwave to space. Thus, if a warmer atmosphere can host more organized convection, then this represents one possible mechanism for an iris-effect. The challenges in modeling, understanding and possibly quantifying a temperature-dependency of convection are, however, substantial.

Efficient quantitative assessment of facial paralysis using iris segmentation and active contour-based key points detection with hybrid classifier.

PubMed

Barbosa, Jocelyn; Lee, Kyubum; Lee, Sunwon; Lodhi, Bilal; Cho, Jae-Gu; Seo, Woo-Keun; Kang, Jaewoo

2016-03-12

Facial palsy or paralysis (FP) is a symptom that loses voluntary muscles movement in one side of the human face, which could be very devastating in the part of the patients. Traditional methods are solely dependent to clinician's judgment and therefore time consuming and subjective in nature. Hence, a quantitative assessment system becomes apparently invaluable for physicians to begin the rehabilitation process; and to produce a reliable and robust method is challenging and still underway. We introduce a novel approach for a quantitative assessment of facial paralysis that tackles classification problem for FP type and degree of severity. Specifically, a novel method of quantitative assessment is presented: an algorithm that extracts the human iris and detects facial landmarks; and a hybrid approach combining the rule-based and machine learning algorithm to analyze and prognosticate facial paralysis using the captured images. A method combining the optimized Daugman's algorithm and Localized Active Contour (LAC) model is proposed to efficiently extract the iris and facial landmark or key points. To improve the performance of LAC, appropriate parameters of initial evolving curve for facial features' segmentation are automatically selected. The symmetry score is measured by the ratio between features extracted from the two sides of the face. Hybrid classifiers (i.e. rule-based with regularized logistic regression) were employed for discriminating healthy and unhealthy subjects, FP type classification, and for facial paralysis grading based on House-Brackmann (H-B) scale. Quantitative analysis was performed to evaluate the performance of the proposed approach. Experiments show that the proposed method demonstrates its efficiency. Facial movement feature extraction on facial images based on iris segmentation and LAC-based key point detection along with a hybrid classifier provides a more efficient way of addressing classification problem on facial palsy type and degree of severity. Combining iris segmentation and key point-based method has several merits that are essential for our real application. Aside from the facial key points, iris segmentation provides significant contribution as it describes the changes of the iris exposure while performing some facial expressions. It reveals the significant difference between the healthy side and the severe palsy side when raising eyebrows with both eyes directed upward, and can model the typical changes in the iris region.

A Conformational Change in C-Reactive Protein Enhances Leukocyte Recruitment and Reactive Oxygen Species Generation in Ischemia/Reperfusion Injury.

PubMed

Thiele, Jan R; Zeller, Johannes; Kiefer, Jurij; Braig, David; Kreuzaler, Sheena; Lenz, Yvonne; Potempa, Lawrence A; Grahammer, Florian; Huber, Tobias B; Huber-Lang, M; Bannasch, Holger; Stark, G Björn; Peter, Karlheinz; Eisenhardt, Steffen U

2018-01-01

C-reactive protein circulates as a pentameric protein (pCRP). pCRP is a well-established diagnostic marker as plasma levels rise in response to tissue injury and inflammation. We recently described pro-inflammatory properties of CRP, which are mediated by conformational changes from pCRP to bioactive isoforms expressing pro-inflammatory neo-epitopes [pCRP* and monomeric C-reactive protein (mCRP)]. Here, we investigate the role of CRP isoforms in renal ischemia/reperfusion injury (IRI). Rat kidneys in animals with and without intraperitoneally injected pCRP were subjected to IRI by the time of pCRP exposure and were subsequently analyzed for monocyte infiltration, caspase-3 expression, and tubular damage. Blood urea nitrogen (BUN) was analyzed pre-ischemia and post-reperfusion. CRP effects on leukocyte recruitment were investigated via intravital imaging of rat-striated muscle IRI. Localized conformational CRP changes were analyzed by immunohistochemistry using conformation specific antibodies. 1,6-bis(phosphocholine)-hexane (1,6-bisPC), which stabilizes CRP in its native pentameric form was used to validate CRP effects. Leukocyte activation was assessed by quantification of reactive oxygen species (ROS) induction by CRP isoforms ex vivo and in vitro through electron spin resonance spectroscopy. Signaling pathways were analyzed by disrupting lipid rafts with nystatin and subsequent ROS detection. In order to confirm the translational relevance of our findings, biopsies of microsurgical human free tissue transfers before and after IRI were examined by immunofluorescence for CRP deposition and co-localization of CD68 + leukocytes. The application of pCRP aggravates tissue damage in renal IRI. 1,6-bisPC reverses these effects via inhibition of the conformational change that leads to exposure of pro-inflammatory epitopes in CRP (pCRP* and mCRP). Structurally altered CRP induces leukocyte-endothelial interaction and induces ROS formation in leukocytes, the latter can be abrogated by blocking lipid raft-dependent signaling pathways with Nystatin. Stabilizing pCRP in its native pentameric state abrogates these pro-inflammatory effects. Importantly, these findings are confirmed in human IRI challenged muscle tissue. These results suggest that CRP is a potent modulator of IRI. Stabilizing the native pCRP conformation represents a promising anti-inflammatory therapeutic strategy by attenuation of leukocyte recruitment and ROS formation, the primary pathomechanisms of IRI.

Real-Time IRI driven by GIRO data

NASA Astrophysics Data System (ADS)

Galkin, Ivan; Huang, Xueqin; Reinisch, Bodo; Bilitza, Dieter; Vesnin, Artem

Real-time extensions of the empirical International Reference Ionosphere (IRI) model are based on assimilative techniques that preserve the IRI formalism which is optimized for the description of climatological ionospheric features. The Global Ionosphere Radio Observatory (GIRO) team has developed critical parts of an IRI Real Time Assimilative Model (IRTAM) for the global ionospheric plasma distribution using measured data available in real time from ~50 ionosondes of the GIRO network, The current assimilation results present global assimilative maps of foF2 and hmF2 that reproduce available data at the sensor sites and smoothly return to the climatological specifications when and where the data are missing, and are free from artificial sharp gradients and short-lived artifacts when viewed in time progression. Animated real-time maps of foF2 and hmF2 are published with a few minutes latency at http://giro.uml.edu/IRTAM/. Our real-time IRI modeling uses morphing, a technique that transforms the climatological ionospheric specifications to match the observations by iteratively computing corrections to the original coefficients of the diurnal/spatial expansions, used in IRI to map the key ionospheric characteristics, while keeping the IRI expansion basis formalism intact. Computation of the updated coefficient set for a given point in time includes analysis of the latest 24-hour history of observations, which allows the morphing technique to sense evolving ionospheric dynamics even with a sparse sensor network. A Non-linear Error Compensation Technique for Associative Restoration (NECTAR), one of the features in our morphing approach, has been in operation at the Lowell GIRO Data Center since 2013. The cornerstone of NECTAR is a recurrent neural network optimizer that is responsible for smoothing the transitions between the grid cells where observations are available. NECTAR has proved suitable for real-time operations that require the assimilation code to be considerate of data uncertainties (noise) and immune to data errors. Future IRTAM work is directed toward accepting a greater diversity of near-real-time sensor data, and the paper discusses potential new data sources and challenges associated with their assimilation.

Promoting seismology education and research via the IRIS Education and Public Outreach Program

NASA Astrophysics Data System (ADS)

Taber, J. J.; Bravo, T. K.; Dorr, P. M.; Hubenthal, M.; Johnson, J. A.; McQuillan, P.; Sumy, D. F.; Welti, R.

2015-12-01

The Incorporated Research Institutions for Seismology's Education and Public Outreach (EPO) program is committed to advancing awareness and understanding of seismology and geophysics, while inspiring careers in the Earth sciences. To achieve this mission, IRIS EPO combines content and research expertise of consortium membership with educational and outreach expertise of IRIS staff to create a portfolio of programs, products, and services that target a range of audiences, including grades 6-12 students and teachers, undergraduate and graduate students, faculty, and the general public. IRIS also partners with UNAVCO and other organizations in support of EarthScope where the facilities are well-suited for sustained engagement of multiple audiences. Examples of research-related EPO products and services include the following resources. Tools developed in collaboration with IRIS Data Services provide public and educational access to data, and to a suite of data products. Teachers can stream seismic data from educational or research sensors into their classroom, and the Active Earth Monitor display, designed for visitor centers, universities and small museums, provides views of recent data along with animations that explain seismology concepts, and stories about recent research. Teachable Moment slide sets, created in collaboration with the University of Portland within 24 hours of major earthquakes, provide interpreted USGS tectonic maps and summaries, animations, visualizations, and other event-specific information so educators can explore newsworthy earthquakes with their students. Intro undergraduate classroom activities have been designed to introduce students to some grand challenges in seismological research, while our Research Experiences for Undergraduates program pairs students with seismology researchers throughout the Consortium and provides the opportunity for the students to present their research at a national meeting. EPO activities are evaluated via a combination of internal and external assessments, with an emphasis on formative evaluation and regular review by an advisory committee of community members. Results from our assessments inform the program's decision-making process, which has allowed IRIS to significantly enhance its EPO activities over time.

FAQs about IRIs.

ERIC Educational Resources Information Center

Paris, Scott G.; Carpenter, Robert D.

2003-01-01

Provides information about informal reading inventories (IRI), an early reading assessment. Explains what IRIs are; who should administer an IRI; when and how to administer an IRI; the reliability of data from IRIs; and the limitations of IRIs. (PM)

Climate information for public health: the role of the IRI climate data library in an integrated knowledge system.

PubMed

del Corral, John; Blumenthal, M Benno; Mantilla, Gilma; Ceccato, Pietro; Connor, Stephen J; Thomson, Madeleine C

2012-09-01

Public health professionals are increasingly concerned about the potential impact of climate variability and change on health outcomes. Protecting public health from the vagaries of climate requires new working relationships between the public health sector and the providers of climate data and information. The Climate Information for Public Health Action initiative at the International Research Institute for Climate and Society (IRI) is designed to increase the public health community's capacity to understand, use and demand appropriate climate data and climate information to mitigate the public health impacts of the climate. Significant challenges to building the capacity of health professionals to use climate information in research and decision-making include the difficulties experienced by many in accessing relevant and timely quality controlled data and information in formats that can be readily incorporated into specific analysis with other data sources. We present here the capacities of the IRI climate data library and show how we have used it to build an integrated knowledge system in the support of the use of climate and environmental information in climate-sensitive decision-making with respect to health. Initiated as an aid facilitating exploratory data analysis for climate scientists, the IRI climate data library has emerged as a powerful tool for interdisciplinary researchers focused on topics related to climate impacts on society, including health.

Antifreeze (glyco)protein mimetic behavior of poly(vinyl alcohol): detailed structure ice recrystallization inhibition activity study.

PubMed

Congdon, Thomas; Notman, Rebecca; Gibson, Matthew I

2013-05-13

This manuscript reports a detailed study on the ability of poly(vinyl alcohol) to act as a biomimetic surrogate for antifreeze(glyco)proteins, with a focus on the specific property of ice-recrystallization inhibition (IRI). Despite over 40 years of study, the underlying mechanisms that govern the action of biological antifreezes are still poorly understood, which is in part due to their limited availability and challenging synthesis. Poly(vinyl alcohol) (PVA) has been shown to display remarkable ice recrystallization inhibition activity despite its major structural differences to native antifreeze proteins. Here, controlled radical polymerization is used to synthesize well-defined PVA, which has enabled us to obtain the first quantitative structure-activity relationships, to probe the role of molecular weight and comonomers on IRI activity. Crucially, it was found that IRI activity is "switched on" when the polymer chain length increases from 10 and 20 repeat units. Substitution of the polymer side chains with hydrophilic or hydrophobic units was found to diminish activity. Hydrophobic modifications to the backbone were slightly more tolerated than side chain modifications, which implies an unbroken sequence of hydroxyl units is necessary for activity. These results highlight that, although hydrophobic domains are key components of IRI activity, the random inclusion of addition hydrophobic units does not guarantee an increase in activity and that the actual polymer conformation is important.

Iris Image Classification Based on Hierarchical Visual Codebook.

PubMed

Zhenan Sun; Hui Zhang; Tieniu Tan; Jianyu Wang

2014-06-01

Iris recognition as a reliable method for personal identification has been well-studied with the objective to assign the class label of each iris image to a unique subject. In contrast, iris image classification aims to classify an iris image to an application specific category, e.g., iris liveness detection (classification of genuine and fake iris images), race classification (e.g., classification of iris images of Asian and non-Asian subjects), coarse-to-fine iris identification (classification of all iris images in the central database into multiple categories). This paper proposes a general framework for iris image classification based on texture analysis. A novel texture pattern representation method called Hierarchical Visual Codebook (HVC) is proposed to encode the texture primitives of iris images. The proposed HVC method is an integration of two existing Bag-of-Words models, namely Vocabulary Tree (VT), and Locality-constrained Linear Coding (LLC). The HVC adopts a coarse-to-fine visual coding strategy and takes advantages of both VT and LLC for accurate and sparse representation of iris texture. Extensive experimental results demonstrate that the proposed iris image classification method achieves state-of-the-art performance for iris liveness detection, race classification, and coarse-to-fine iris identification. A comprehensive fake iris image database simulating four types of iris spoof attacks is developed as the benchmark for research of iris liveness detection.

An Engineered Organoid Culture Model That Incorporates Human Mesenchymal and Epithelial Cells to Model Palatal Fusion.

EPA Science Inventory

During embryonic development, fusion events are critical to morphogenesis of organs and tissues, including the iris, urethra, heart, neural tube, and secondary palate. Modeling this process in vitro is challenging as the interactions of mesenchymal and epithelial cells can be cr...

Application synergies between the NASA Pre- Aerosol Cloud and ocean Ecosystem (PACE) and Hyperspectral Infrared Imager (HyspIRI) missions

NASA Astrophysics Data System (ADS)

Lee, C. M.; Omar, A. H.; Hook, S. J.; Tzortziou, M.; Luvall, J. C.; Turner, W. W.

2016-02-01

Observations from the Pre-Aerosol Cloud and ocean Ecosystem (PACE) and Hyperspectral InfraRed Imager (HyspIRI) satellite missions are highly complementary and have the potential to significantly advance understanding of various science and applications challenges in the ocean sciences and water quality communities. Scheduled for launch in the 2022 timeframe, PACE is designed to make climate-quality global measurements essential for understanding ocean biology, biogeochemistry and ecology, and determining the role of the ocean in global biogeochemical cycling and ocean ecology, and how it affects and is affected by climate change. PACE will provide high signal-to-noise, hyperspectral observations over an extended spectral range (UV to SWIR) and will have global coverage every 1-2 days, at approximately 1 km spatial resolution; furthermore, PACE is currently designed to include a polarimeter, which will vastly improve atmospheric correction algorithms over water bodies. The PACE mission will enable advances in applications across a range of areas, including oceans, climate, water resources, ecological forecasting, disasters, human health and air quality. HyspIRI, with contiguous measurements in VSWIR, and multispectral measurements in TIR, will be able to provide detailed spectral observations and higher spatial resolution (30 to 60-m) over aquatic systems, but at a temporal resolution that is approximately 5-16 days. HyspIRI would enable improved, detailed studies of aquatic ecosystems, including benthic communities, algal blooms, coral reefs, and wetland species distribution as well as studies of water quality indicators or pollutants such as oil spills, suspended sediment, and colored dissolved organic matter. Together, PACE and HyspIRI will be able to address numerous applications and science priorities, including improving and extending climate data records, and studies of inland, coastal and ocean environments.

Anisometropic amblyopia in a case of type 2 Waardenburg syndrome.

PubMed

Akal, Ali; Göncü, Tugba; Boyaci, Nurefsan; Yılmaz, Ömer Faruk

2013-12-18

This study presents a case of an 8-year-old boy with iris heterochromia and anisometropic amblyopia who was diagnosed with Waardenburg syndrome (WS) type 2. An ophthalmic examination revealed iris heterochromia and anisometropic amblyopia in our patient. In the systemic examination, a white forelock and vitiligo on the arms and body were observed and neurosensory hearing loss was revealed, for which the patient used hearing aids. Identification and typing of patients with WS is crucial to address neurosensory hearing loss, glaucoma and fundus changes. While it might be challenging to communicate with a patient with speech and hearing problems, visual acuity should be examined carefully and probable amblyopia should be identified. Anterior segment changes and signs of glaucoma should also be evaluated in detail.

Iris Matching Based on Personalized Weight Map.

PubMed

Dong, Wenbo; Sun, Zhenan; Tan, Tieniu

2011-09-01

Iris recognition typically involves three steps, namely, iris image preprocessing, feature extraction, and feature matching. The first two steps of iris recognition have been well studied, but the last step is less addressed. Each human iris has its unique visual pattern and local image features also vary from region to region, which leads to significant differences in robustness and distinctiveness among the feature codes derived from different iris regions. However, most state-of-the-art iris recognition methods use a uniform matching strategy, where features extracted from different regions of the same person or the same region for different individuals are considered to be equally important. This paper proposes a personalized iris matching strategy using a class-specific weight map learned from the training images of the same iris class. The weight map can be updated online during the iris recognition procedure when the successfully recognized iris images are regarded as the new training data. The weight map reflects the robustness of an encoding algorithm on different iris regions by assigning an appropriate weight to each feature code for iris matching. Such a weight map trained by sufficient iris templates is convergent and robust against various noise. Extensive and comprehensive experiments demonstrate that the proposed personalized iris matching strategy achieves much better iris recognition performance than uniform strategies, especially for poor quality iris images.

Antigen-Specific Interferon-Gamma Responses and Innate Cytokine Balance in TB-IRIS

PubMed Central

Goovaerts, Odin; Jennes, Wim; Massinga-Loembé, Marguerite; Ceulemans, Ann; Worodria, William; Mayanja-Kizza, Harriet; Colebunders, Robert; Kestens, Luc

2014-01-01

Background Tuberculosis-associated immune reconstitution inflammatory syndrome (TB-IRIS) remains a poorly understood complication in HIV-TB patients receiving antiretroviral therapy (ART). TB-IRIS could be associated with an exaggerated immune response to TB-antigens. We compared the recovery of IFNγ responses to recall and TB-antigens and explored in vitro innate cytokine production in TB-IRIS patients. Methods In a prospective cohort study of HIV-TB co-infected patients treated for TB before ART initiation, we compared 18 patients who developed TB-IRIS with 18 non-IRIS controls matched for age, sex and CD4 count. We analyzed IFNγ ELISpot responses to CMV, influenza, TB and LPS before ART and during TB-IRIS. CMV and LPS stimulated ELISpot supernatants were subsequently evaluated for production of IL-12p70, IL-6, TNFα and IL-10 by Luminex. Results Before ART, all responses were similar between TB-IRIS patients and non-IRIS controls. During TB-IRIS, IFNγ responses to TB and influenza antigens were comparable between TB-IRIS patients and non-IRIS controls, but responses to CMV and LPS remained significantly lower in TB-IRIS patients. Production of innate cytokines was similar between TB-IRIS patients and non-IRIS controls. However, upon LPS stimulation, IL-6/IL-10 and TNFα/IL-10 ratios were increased in TB-IRIS patients compared to non-IRIS controls. Conclusion TB-IRIS patients did not display excessive IFNγ responses to TB-antigens. In contrast, the reconstitution of CMV and LPS responses was delayed in the TB-IRIS group. For LPS, this was linked with a pro-inflammatory shift in the innate cytokine balance. These data are in support of a prominent role of the innate immune system in TB-IRIS. PMID:25415590

Iris reconstruction combined with iris-claw intraocular lens implantation for the management of iris-lens injured patients.

PubMed

Hu, Shufang; Wang, Mingling; Xiao, Tianlin; Zhao, Zhenquan

2016-03-01

To study the efficiency and safety of iris reconstruction combined with iris-claw intraocular lens (IOL) implantation in the patients with iris-lens injuries. Retrospective, noncomparable consecutive case series study. Eleven patients (11 eyes) following iris-lens injuries underwent iris reconstructions combined with iris-claw IOL implantations. Clinical data, such as cause and time of injury, visual acuity (VA), iris and lens injuries, surgical intervention, follow-up period, corneal endothelial cell count, and optical coherence tomography, were collected. Uncorrected VA (UCVA) in all injured eyes before combined surgery was equal to or <20/1000. Within a 1.1-4.2-year follow-up period, a significant increase, equal to or better than 20/66, in UCVA was observed in six (55%) cases, and in best-corrected VA (BCVA) was observed in nine (82%) cases. Postoperative BCVA was 20/40 or better in seven cases (64%). After combined surgery, the iris returned to its natural round shape or smaller pupil, and the iris-claw IOLs in the 11 eyes were well-positioned on the anterior surface of reconstructed iris. No complications occurred in those patients. Iris reconstruction combined with iris-claw IOL implantation is a safe and efficient procedure for an eye with iris-lens injury in the absence of capsular support.

EMERALD: Coping with the Explosion of Seismic Data

NASA Astrophysics Data System (ADS)

West, J. D.; Fouch, M. J.; Arrowsmith, R.

2009-12-01

The geosciences are currently generating an unparalleled quantity of new public broadband seismic data with the establishment of large-scale seismic arrays such as the EarthScope USArray, which are enabling new and transformative scientific discoveries of the structure and dynamics of the Earth’s interior. Much of this explosion of data is a direct result of the formation of the IRIS consortium, which has enabled an unparalleled level of open exchange of seismic instrumentation, data, and methods. The production of these massive volumes of data has generated new and serious data management challenges for the seismological community. A significant challenge is the maintenance and updating of seismic metadata, which includes information such as station location, sensor orientation, instrument response, and clock timing data. This key information changes at unknown intervals, and the changes are not generally communicated to data users who have already downloaded and processed data. Another basic challenge is the ability to handle massive seismic datasets when waveform file volumes exceed the fundamental limitations of a computer’s operating system. A third, long-standing challenge is the difficulty of exchanging seismic processing codes between researchers; each scientist typically develops his or her own unique directory structure and file naming convention, requiring that codes developed by another researcher be rewritten before they can be used. To address these challenges, we are developing EMERALD (Explore, Manage, Edit, Reduce, & Analyze Large Datasets). The overarching goal of the EMERALD project is to enable more efficient and effective use of seismic datasets ranging from just a few hundred to millions of waveforms with a complete database-driven system, leading to higher quality seismic datasets for scientific analysis and enabling faster, more efficient scientific research. We will present a preliminary (beta) version of EMERALD, an integrated, extensible, standalone database server system based on the open-source PostgreSQL database engine. The system is designed for fast and easy processing of seismic datasets, and provides the necessary tools to manage very large datasets and all associated metadata. EMERALD provides methods for efficient preprocessing of seismic records; large record sets can be easily and quickly searched, reviewed, revised, reprocessed, and exported. EMERALD can retrieve and store station metadata and alert the user to metadata changes. The system provides many methods for visualizing data, analyzing dataset statistics, and tracking the processing history of individual datasets. EMERALD allows development and sharing of visualization and processing methods using any of 12 programming languages. EMERALD is designed to integrate existing software tools; the system provides wrapper functionality for existing widely-used programs such as GMT, SOD, and TauP. Users can interact with EMERALD via a web browser interface, or they can directly access their data from a variety of database-enabled external tools. Data can be imported and exported from the system in a variety of file formats, or can be directly requested and downloaded from the IRIS DMC from within EMERALD.

Three-Dimensional Morphometric Analysis of the Iris by Swept-Source Anterior Segment Optical Coherence Tomography in a Caucasian Population.

PubMed

Invernizzi, Alessandro; Giardini, Piero; Cigada, Mario; Viola, Francesco; Staurenghi, Giovanni

2015-07-01

We analyzed by swept-source anterior segment optical coherence tomography (SS-ASOCT) the three-dimensional iris morphology in a Caucasian population, and correlated the findings with iris color, iris sectors, subject age, and sex. One eye each from consecutive healthy emmetropic (refractive spherical equivalent ± 3 diopters) volunteers were selected for the study. The enrolled eye underwent standardized anterior segment photography to assess iris color. Iris images were assessed by SS-ASOCT for volume, thickness, width, and pupil size. Sectoral variations of morphometric data among the superior, nasal, inferior, and temporal sectors were recorded. A total of 135 eyes from 57 males and 78 females, age 49 ± 17 years, fulfilled the inclusion criteria. All iris morphometric parameters varied significantly among the different sectors (all P < 0.0001). Iris total volume and thickness were significantly correlated with increasingly darker pigmentation (P < 0.0001, P = 0.0384, respectively). Neither width nor pupil diameter was influenced by iris color. Age did not affect iris volume or thickness; iris width increased and pupil diameter decreased with age (rs = 0.52, rs = -0.58, respectively). There was no effect of sex on iris volume, thickness, or pupil diameter; iris width was significantly greater in males (P = 0.007). Morphology of the iris varied by iris sector, and iris color was associated with differences in iris volume and thickness. Morphological parameter variations associated with iris color, sector, age, and sex can be used to identify pathological changes in suspect eyes. To be effective in clinical settings, construction of iris morphological databases for different ethnic and racial populations is essential.

Overview of the NASA Wallops Flight Facility Mobile Range Control System

NASA Technical Reports Server (NTRS)

Davis, Rodney A.; Semancik, Susan K.; Smith, Donna C.; Stancil, Robert K.

1999-01-01

The NASA GSFC's Wallops Flight Facility (WFF) Mobile Range Control System (MRCS) is based on the functionality of the WFF Range Control Center at Wallops Island, Virginia. The MRCS provides real time instantaneous impact predictions, real time flight performance data, and other critical information needed by mission and range safety personnel in support of range operations at remote launch sites. The MRCS integrates a PC telemetry processing system (TELPro), a PC radar processing system (PCDQS), multiple Silicon Graphics display workstations (IRIS), and communication links within a mobile van for worldwide support of orbital, suborbital, and aircraft missions. This paper describes the MRCS configuration; the TELPro's capability to provide single/dual telemetry tracking and vehicle state data processing; the PCDQS' capability to provide real time positional data and instantaneous impact prediction for up to 8 data sources; and the IRIS' user interface for setup/display options. With portability, PC-based data processing, high resolution graphics, and flexible multiple source support, the MRCS system is proving to be responsive to the ever-changing needs of a variety of increasingly complex missions.

Iris reconstruction combined with iris-claw intraocular lens implantation for the management of iris-lens injured patients

PubMed Central

Hu, Shufang; Wang, Mingling; Xiao, Tianlin; Zhao, Zhenquan

2016-01-01

Aim: To study the efficiency and safety of iris reconstruction combined with iris-claw intraocular lens (IOL) implantation in the patients with iris-lens injuries. Settings and Design: Retrospective, noncomparable consecutive case series study. Materials and Methods: Eleven patients (11 eyes) following iris-lens injuries underwent iris reconstructions combined with iris-claw IOL implantations. Clinical data, such as cause and time of injury, visual acuity (VA), iris and lens injuries, surgical intervention, follow-up period, corneal endothelial cell count, and optical coherence tomography, were collected. Results: Uncorrected VA (UCVA) in all injured eyes before combined surgery was equal to or <20/1000. Within a 1.1–4.2-year follow-up period, a significant increase, equal to or better than 20/66, in UCVA was observed in six (55%) cases, and in best-corrected VA (BCVA) was observed in nine (82%) cases. Postoperative BCVA was 20/40 or better in seven cases (64%). After combined surgery, the iris returned to its natural round shape or smaller pupil, and the iris-claw IOLs in the 11 eyes were well-positioned on the anterior surface of reconstructed iris. No complications occurred in those patients. Conclusions: Iris reconstruction combined with iris-claw IOL implantation is a safe and efficient procedure for an eye with iris-lens injury in the absence of capsular support. PMID:27146932

An investigation of kV CBCT image quality and dose reduction for volume-of-interest imaging using dynamic collimation

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

Parsons, David, E-mail: david.parsons@dal.ca, E-mail: james.robar@cdha.nshealth.ca; Robar, James L., E-mail: david.parsons@dal.ca, E-mail: james.robar@cdha.nshealth.ca

2015-09-15

Purpose: The focus of this work was to investigate the improvements in image quality and dose reduction for volume-of-interest (VOI) kilovoltage-cone beam CT (CBCT) using dynamic collimation. Methods: A prototype iris aperture was used to track a VOI during a CBCT acquisition. The current aperture design is capable of 1D translation as a function of gantry angle and dynamic adjustment of the iris radius. The aperture occupies the location of the bow-tie filter on a Varian On-Board Imager system. CBCT and planar image quality were investigated as a function of aperture radius, while maintaining the same dose to the VOI,more » for a 20 cm diameter cylindrical water phantom with a 9 mm diameter bone insert centered on isocenter. Corresponding scatter-to-primary ratios (SPR) were determined at the detector plane with Monte Carlo simulation using EGSnrc. Dose distributions for various sizes VOI were modeled using a dynamic BEAMnrc library and DOSXYZnrc. The resulting VOI dose distributions were compared to full-field distributions. Results: SPR was reduced by a factor of 8.4 when decreasing iris diameter from 21.2 to 2.4 cm (at isocenter). Depending upon VOI location and size, dose was reduced to 16%–90% of the full-field value along the central axis plane and down to 4% along the axis of rotation, while maintaining the same dose to the VOI compared to full-field techniques. When maintaining constant dose to the VOI, this change in iris diameter corresponds to a factor increase of approximately 1.6 in image contrast and a factor decrease in image noise of approximately 1.2. This results in a measured gain in contrast-to-noise ratio by a factor of approximately 2.0. Conclusions: The presented VOI technique offers improved image quality for image-guided radiotherapy while sparing the surrounding volume of unnecessary dose compared to full-field techniques.« less

Optical Coherence Tomography Angiography Features of Iris Racemose Hemangioma in 4 Cases.

PubMed

Chien, Jason L; Sioufi, Kareem; Ferenczy, Sandor; Say, Emil Anthony T; Shields, Carol L

2017-10-01

Optical coherence tomography angiography (OCTA) allows visualization of iris racemose hemangioma course and its relation to the normal iris microvasculature. To describe OCTA features of iris racemose hemangioma. Descriptive, noncomparative case series at a tertiary referral center (Ocular Oncology Service of Wills Eye Hospital). Patients diagnosed with unilateral iris racemose hemangioma were included in the study. Features of iris racemose hemangioma on OCTA. Four eyes of 4 patients with unilateral iris racemose hemangioma were included in the study. Mean patient age was 50 years, all patients were white, and Snellen visual acuity was 20/20 in each case. All eyes had sectoral iris racemose hemangioma without associated iris or ciliary body solid tumor on clinical examination and ultrasound biomicroscopy. By anterior segment OCT, the racemose hemangioma was partially visualized in all cases. By OCTA, the hemangioma was clearly visualized as a uniform large-caliber vascular tortuous loop with intense flow characteristics superimposed over small-caliber radial iris vessels against a background of low-signal iris stroma. The vascular course on OCTA resembled a light bulb filament (filament sign), arising from the peripheral iris (base of light bulb) and forming a tortuous loop on reaching its peak (midfilament) near the pupil (n = 3) or midzonal iris (n = 1), before returning to the peripheral iris (base of light bulb). Intravenous fluorescein angiography performed in 1 eye depicted the iris hemangioma; however, small-caliber radial iris vessels were more distinct on OCTA than intravenous fluorescein angiography. Optical coherence tomography angiography is a noninvasive vascular imaging modality that clearly depicts the looping course of iris racemose hemangioma. Optical coherence tomography angiography depicted fine details of radial iris vessels, not distinct on intravenous fluorescein angiography.

Iris Crypts Influence Dynamic Changes of Iris Volume.

PubMed

Chua, Jacqueline; Thakku, Sri Gowtham; Tun, Tin A; Nongpiur, Monisha E; Tan, Marcus Chiang Lee; Girard, Michael J A; Wong, Tien Yin; Quah, Joanne Hui Min; Aung, Tin; Cheng, Ching-Yu

2016-10-01

To determine the association of iris surface features with iris volume change after physiologic pupil dilation in adults. Cross-sectional observational study. Chinese adults aged ≥ 50 years without ocular diseases. Digital iris photographs were taken from eyes of each participant and graded for crypts (by number and size) and furrows (by number and circumferential extent) following a standardized grading scheme. Iris color was measured objectively, using the Commission Internationale de l'Eclairage (CIE) L* color parameter (higher value denoting lighter iris). The anterior segment was imaged by swept-source optical coherence tomography (SS-OCT) (Casia; Tomey, Nagoya, Japan) under bright light and dark room conditions. Iris volumes in light and dark conditions were measured with custom semiautomated software, and the change in iris volume was quantified. Associations of the change in iris volume after pupil dilation with underlying iris surface features in right eyes were assessed using linear regression analysis. Iris volume change after physiologic pupil dilation from light to dark condition. A total of 65 Chinese participants (mean age, 59.8±5.7 years) had gradable data for iris surface features. In light condition, higher iris crypt grade was associated independently with smaller iris volume (β [change in iris volume in millimeters per crypt grade increment] = -1.43, 95% confidence interval [CI], -2.26 to -0.59; P = 0.001) and greater reduction of iris volume on pupil dilation (β [change in iris volume in millimeters per crypt grade increment] = 0.23, 95% CI, 0.06-0.40; P = 0.010), adjusting for age, gender, presence of corneal arcus, and change in pupil size. Iris furrows and iris color were not associated with iris volume in light condition or change in iris volume (all P > 0.05). Although few Chinese persons have multiple crypts on their irides, irides with more crypts were significantly thinner and lost more volume on pupil dilation. In view that the latter feature is known to be protective for acute angle-closure attack, it is likely that the macroscopic and microscopic composition of the iris is a contributing feature to angle-closure disease. Copyright © 2016 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

Fuzzy difference-of-Gaussian-based iris recognition method for noisy iris images

NASA Astrophysics Data System (ADS)

Kang, Byung Jun; Park, Kang Ryoung; Yoo, Jang-Hee; Moon, Kiyoung

2010-06-01

Iris recognition is used for information security with a high confidence level because it shows outstanding recognition accuracy by using human iris patterns with high degrees of freedom. However, iris recognition accuracy can be reduced by noisy iris images with optical and motion blurring. We propose a new iris recognition method based on the fuzzy difference-of-Gaussian (DOG) for noisy iris images. This study is novel in three ways compared to previous works: (1) The proposed method extracts iris feature values using the DOG method, which is robust to local variations of illumination and shows fine texture information, including various frequency components. (2) When determining iris binary codes, image noises that cause the quantization error of the feature values are reduced with the fuzzy membership function. (3) The optimal parameters of the DOG filter and the fuzzy membership function are determined in terms of iris recognition accuracy. Experimental results showed that the performance of the proposed method was better than that of previous methods for noisy iris images.

Enhanced iris recognition method based on multi-unit iris images

NASA Astrophysics Data System (ADS)

Shin, Kwang Yong; Kim, Yeong Gon; Park, Kang Ryoung

2013-04-01

For the purpose of biometric person identification, iris recognition uses the unique characteristics of the patterns of the iris; that is, the eye region between the pupil and the sclera. When obtaining an iris image, the iris's image is frequently rotated because of the user's head roll toward the left or right shoulder. As the rotation of the iris image leads to circular shifting of the iris features, the accuracy of iris recognition is degraded. To solve this problem, conventional iris recognition methods use shifting of the iris feature codes to perform the matching. However, this increases the computational complexity and level of false acceptance error. To solve these problems, we propose a novel iris recognition method based on multi-unit iris images. Our method is novel in the following five ways compared with previous methods. First, to detect both eyes, we use Adaboost and a rapid eye detector (RED) based on the iris shape feature and integral imaging. Both eyes are detected using RED in the approximate candidate region that consists of the binocular region, which is determined by the Adaboost detector. Second, we classify the detected eyes into the left and right eyes, because the iris patterns in the left and right eyes in the same person are different, and they are therefore considered as different classes. We can improve the accuracy of iris recognition using this pre-classification of the left and right eyes. Third, by measuring the angle of head roll using the two center positions of the left and right pupils, detected by two circular edge detectors, we obtain the information of the iris rotation angle. Fourth, in order to reduce the error and processing time of iris recognition, adaptive bit-shifting based on the measured iris rotation angle is used in feature matching. Fifth, the recognition accuracy is enhanced by the score fusion of the left and right irises. Experimental results on the iris open database of low-resolution images showed that the averaged equal error rate of iris recognition using the proposed method was 4.3006%, which is lower than that of other methods.

Results in Combined Cataract Surgery With Prosthetic Iris Implantation in Patients With Previous Iridocyclectomy for Iris Melanoma.

PubMed

Snyder, Michael E; Osher, Robert H; Wladecki, Trisha M; Perez, Mauricio A; Augsburger, James J; Corrêa, Zélia

2017-03-01

To present visual and functional results following implantation of iris prosthesis combined with cataract surgery in eyes with previous iridocyclectomy for iris melanoma or presumed iris melanoma. Retrospective noncomparative case series. Sixteen patients (16 eyes) with iris defects after iridocyclectomy for iris melanoma in 15 cases and iris adenoma in 1 case underwent prosthetic iris device implantation surgery. Prosthetic iris implantation was combined with phacoemulsification and intraocular lens (IOL) implantation. The visual acuity, subjective glare and photophobia reduction, anatomic outcome, and complications were reviewed. Best-corrected visual acuity was improved in 13 eyes (81.25%), remained stable in 2 eyes (12.25%), and decreased in 1 eye (6.25%). Photophobia and glare improved in every case except for 1 (93.75%). Notably, after surgery 12 patients (75.00%) reported no photophobia and 10 patients (62.50%) reported no glare. The median postoperative follow-up was 29.5 months, with a minimum of 5 months and a maximum of 189 months. All iris devices were in the correct position, and all eyes achieved the desired anatomic result. The IOL optic edges were covered in all areas by either residual iris or opaque portions of a prosthetic iris device. In patients who have undergone previous iridocyclectomy for presumed iris melanoma, combined cataract surgery and iris prosthesis placement, with or without iris reconstruction, can lead to visual improvement as well as reduction of both glare and photophobia. Copyright © 2016 Elsevier Inc. All rights reserved.

Trade off between variable and fixed size normalization in orthogonal polynomials based iris recognition system.

PubMed

Krishnamoorthi, R; Anna Poorani, G

2016-01-01

Iris normalization is an important stage in any iris biometric, as it has a propensity to trim down the consequences of iris distortion. To indemnify the variation in size of the iris owing to the action of stretching or enlarging the pupil in iris acquisition process and camera to eyeball distance, two normalization schemes has been proposed in this work. In the first method, the iris region of interest is normalized by converting the iris into the variable size rectangular model in order to avoid the under samples near the limbus border. In the second method, the iris region of interest is normalized by converting the iris region into a fixed size rectangular model in order to avoid the dimensional discrepancies between the eye images. The performance of the proposed normalization methods is evaluated with orthogonal polynomials based iris recognition in terms of FAR, FRR, GAR, CRR and EER.

Anisometropic amblyopia in a case of type 2 Waardenburg syndrome

PubMed Central

Akal, Ali; Göncü, Tugba; Boyaci, Nurefsan; Yılmaz, Ömer Faruk

2013-01-01

This study presents a case of an 8-year-old boy with iris heterochromia and anisometropic amblyopia who was diagnosed with Waardenburg syndrome (WS) type 2. An ophthalmic examination revealed iris heterochromia and anisometropic amblyopia in our patient. In the systemic examination, a white forelock and vitiligo on the arms and body were observed and neurosensory hearing loss was revealed, for which the patient used hearing aids. Identification and typing of patients with WS is crucial to address neurosensory hearing loss, glaucoma and fundus changes. While it might be challenging to communicate with a patient with speech and hearing problems, visual acuity should be examined carefully and probable amblyopia should be identified. Anterior segment changes and signs of glaucoma should also be evaluated in detail. PMID:24351514

Toward More Accurate Iris Recognition Using Cross-Spectral Matching.

PubMed

Nalla, Pattabhi Ramaiah; Kumar, Ajay

2017-01-01

Iris recognition systems are increasingly deployed for large-scale applications such as national ID programs, which continue to acquire millions of iris images to establish identity among billions. However, with the availability of variety of iris sensors that are deployed for the iris imaging under different illumination/environment, significant performance degradation is expected while matching such iris images acquired under two different domains (either sensor-specific or wavelength-specific). This paper develops a domain adaptation framework to address this problem and introduces a new algorithm using Markov random fields model to significantly improve cross-domain iris recognition. The proposed domain adaptation framework based on the naive Bayes nearest neighbor classification uses a real-valued feature representation, which is capable of learning domain knowledge. Our approach to estimate corresponding visible iris patterns from the synthesis of iris patches in the near infrared iris images achieves outperforming results for the cross-spectral iris recognition. In this paper, a new class of bi-spectral iris recognition system that can simultaneously acquire visible and near infra-red images with pixel-to-pixel correspondences is proposed and evaluated. This paper presents experimental results from three publicly available databases; PolyU cross-spectral iris image database, IIITD CLI and UND database, and achieve outperforming results for the cross-sensor and cross-spectral iris matching.

Infrared Imagery of Shuttle (IRIS). Task 1

NASA Technical Reports Server (NTRS)

Chocol, C. J.

1977-01-01

Assessment of available IR sensor technology showed that the four aerothermodynamic conditions of interest during the entry trajectory of space shuttle can be accommodated by an aircraft flying parallel to the orbiter reentry ground track. Thermal information from the sides of the vehicle can be obtained with degraded performance (temperatures below 800 K) by flying the C-141 aircraft on the opposite side of the shuttle ground track and in the direction opposite that which is optimum for lower surface viewing. An acquisition system using a 6.25-cm aperture telescope and a single indium antimonide detector were designed to meet the acquisition requirements and interface with the 91.5-cm telescope with minimum modification. An image plane system using 600 indium antimonide detectors in two arrays which requires no modification to the existing telescope was also designed. Currently available components were used in a data handling system with interfaces with the experimentors station and the HP2100 computer.

A Model-Based Approach for the Measurement of Eye Movements Using Image Processing

NASA Technical Reports Server (NTRS)

Sung, Kwangjae; Reschke, Millard F.

1997-01-01

This paper describes a video eye-tracking algorithm which searches for the best fit of the pupil modeled as a circular disk. The algorithm is robust to common image artifacts such as the droopy eyelids and light reflections while maintaining the measurement resolution available by the centroid algorithm. The presented algorithm is used to derive the pupil size and center coordinates, and can be combined with iris-tracking techniques to measure ocular torsion. A comparison search method of pupil candidates using pixel coordinate reference lookup tables optimizes the processing requirements for a least square fit of the circular disk model. This paper includes quantitative analyses and simulation results for the resolution and the robustness of the algorithm. The algorithm presented in this paper provides a platform for a noninvasive, multidimensional eye measurement system which can be used for clinical and research applications requiring the precise recording of eye movements in three-dimensional space.

PANEL LIBRARY AND EDITOR

NASA Technical Reports Server (NTRS)

Raible, E.

1994-01-01

The Panel Library and Editor is a graphical user interface (GUI) builder for the Silicon Graphics IRIS workstation family. The toolkit creates "widgets" which can be manipulated by the user. Its appearance is similar to that of the X-Windows System. The Panel Library is written in C and is used by programmers writing user-friendly mouse-driven applications for the IRIS. GUIs built using the Panel Library consist of "actuators" and "panels." Actuators are buttons, dials, sliders, or other mouse-driven symbols. Panels are groups of actuators that occupy separate windows on the IRIS workstation. The application user can alter variables in the graphics program, or fire off functions with a click on a button. The evolution of data values can be tracked with meters and strip charts, and dialog boxes with text processing can be built. Panels can be stored as icons when not in use. The Panel Editor is a program used to interactively create and test panel library interfaces in a simple and efficient way. The Panel Editor itself uses a panel library interface, so all actions are mouse driven. Extensive context-sensitive on-line help is provided. Programmers can graphically create and test the user interface without writing a single line of code. Once an interface is judged satisfactory, the Panel Editor will dump it out as a file of C code that can be used in an application. The Panel Library (v9.8) and Editor (v1.1) are written in C-Language (63%) and Scheme, a dialect of LISP, (37%) for Silicon Graphics 4D series workstations running IRIX 3.2 or higher. Approximately 10Mb of disk space is required once compiled. 1.5Mb of main memory is required to execute the panel editor. This program is available on a .25 inch streaming magnetic tape cartridge in UNIX tar format for an IRIS, and includes a copy of XScheme, the public-domain Scheme interpreter used by the Panel Editor. The Panel Library Programmer's Manual is included on the distribution media. The Panel Library and Editor were released to COSMIC in 1991. Silicon Graphics, IRIS, and IRIX are trademarks of Silicon Graphics, Inc. X-Window System is a trademark of Massachusetts Institute of Technology.

Diagnosis and Management of Iridocorneal Endothelial Syndrome

PubMed Central

Sacchetti, Marta; Mantelli, Flavio; Macchi, Ilaria; Ambrosio, Oriella; Rama, Paolo

2015-01-01

The iridocorneal endothelial (ICE) syndrome is a rare ocular disorder that includes a group of conditions characterized by structural and proliferative abnormalities of the corneal endothelium, the anterior chamber angle, and the iris. Common clinical features include corneal edema, secondary glaucoma, iris atrophy, and pupillary anomalies, ranging from distortion to polycoria. The main subtypes of this syndrome are the progressive iris atrophy, the Cogan-Reese syndrome, and the Chandler syndrome. ICE syndrome is usually diagnosed in women in the adult age. Clinical history and complete eye examination including tonometry and gonioscopy are necessary to reach a diagnosis. Imaging techniques, such as in vivo confocal microscopy and ultrasound biomicroscopy, are used to confirm the diagnosis by revealing the presence of “ICE-cells” on the corneal endothelium and the structural changes of the anterior chamber angle. An early diagnosis is helpful to better manage the most challenging complications such as secondary glaucoma and corneal edema. Treatment of ICE-related glaucoma often requires glaucoma filtering surgery with antifibrotic agents and the use of glaucoma drainage implants should be considered early in the management of these patients. Visual impairment and pain associated with corneal edema can be successfully managed with endothelial keratoplasty. PMID:26451377

Knowing what the brain is seeing in three dimensions: A novel, noninvasive, sensitive, accurate, and low-noise technique for measuring ocular torsion.

PubMed

Otero-Millan, Jorge; Roberts, Dale C; Lasker, Adrian; Zee, David S; Kheradmand, Amir

2015-01-01

Torsional eye movements are rotations of the eye around the line of sight. Measuring torsion is essential to understanding how the brain controls eye position and how it creates a veridical perception of object orientation in three dimensions. Torsion is also important for diagnosis of many vestibular, neurological, and ophthalmological disorders. Currently, there are multiple devices and methods that produce reliable measurements of horizontal and vertical eye movements. Measuring torsion, however, noninvasively and reliably has been a longstanding challenge, with previous methods lacking real-time capabilities or suffering from intrusive artifacts. We propose a novel method for measuring eye movements in three dimensions using modern computer vision software (OpenCV) and concepts of iris recognition. To measure torsion, we use template matching of the entire iris and automatically account for occlusion of the iris and pupil by the eyelids. The current setup operates binocularly at 100 Hz with noise <0.1° and is accurate within 20° of gaze to the left, to the right, and up and 10° of gaze down. This new method can be widely applicable and fill a gap in many scientific and clinical disciplines.

Knowing what the brain is seeing in three dimensions: A novel, noninvasive, sensitive, accurate, and low-noise technique for measuring ocular torsion

PubMed Central

Otero-Millan, Jorge; Roberts, Dale C.; Lasker, Adrian; Zee, David S.; Kheradmand, Amir

2015-01-01

Torsional eye movements are rotations of the eye around the line of sight. Measuring torsion is essential to understanding how the brain controls eye position and how it creates a veridical perception of object orientation in three dimensions. Torsion is also important for diagnosis of many vestibular, neurological, and ophthalmological disorders. Currently, there are multiple devices and methods that produce reliable measurements of horizontal and vertical eye movements. Measuring torsion, however, noninvasively and reliably has been a longstanding challenge, with previous methods lacking real-time capabilities or suffering from intrusive artifacts. We propose a novel method for measuring eye movements in three dimensions using modern computer vision software (OpenCV) and concepts of iris recognition. To measure torsion, we use template matching of the entire iris and automatically account for occlusion of the iris and pupil by the eyelids. The current setup operates binocularly at 100 Hz with noise <0.1° and is accurate within 20° of gaze to the left, to the right, and up and 10° of gaze down. This new method can be widely applicable and fill a gap in many scientific and clinical disciplines. PMID:26587699

Iris Location Algorithm Based on the CANNY Operator and Gradient Hough Transform

NASA Astrophysics Data System (ADS)

Zhong, L. H.; Meng, K.; Wang, Y.; Dai, Z. Q.; Li, S.

2017-12-01

In the iris recognition system, the accuracy of the localization of the inner and outer edges of the iris directly affects the performance of the recognition system, so iris localization has important research meaning. Our iris data contain eyelid, eyelashes, light spot and other noise, even the gray transformation of the images is not obvious, so the general methods of iris location are unable to realize the iris location. The method of the iris location based on Canny operator and gradient Hough transform is proposed. Firstly, the images are pre-processed; then, calculating the gradient information of images, the inner and outer edges of iris are coarse positioned using Canny operator; finally, according to the gradient Hough transform to realize precise localization of the inner and outer edge of iris. The experimental results show that our algorithm can achieve the localization of the inner and outer edges of the iris well, and the algorithm has strong anti-interference ability, can greatly reduce the location time and has higher accuracy and stability.

The Immune Pathogenesis of Immune Reconstitution Inflammatory Syndrome Associated with Highly Active Antiretroviral Therapy in AIDS

PubMed Central

Zhou, Huaying; He, Yan; Chen, Zi; He, Bo; He, Mei

2014-01-01

Abstract The present study investigated the immunological pathogenesis of immune reconstitution inflammatory syndrome (IRIS) in acquired immunodeficiency syndrome (AIDS) patients undergoing highly active antiretroviral therapy (HAART). A total of 238 patients with AIDS who received initial HAART were included in this prospective cohort study. Blood samples were collected immediately, at baseline, at week 12, and at week 24 after initial HAART and at the onset of IRIS. Lymphocyte subsets, Th1 and Th2 cytokines, and interleukin (IL)-7 levels were measured by flow cytometry or ELISA. Among the 238 patients with AIDS who received HAART, 47 patients developed IRIS. The percentages of CD4+ and CD8+ naive, memory, and activated cells exhibited no significant differences between AIDS patients with and without IRIS 24 weeks after initial HAART. The percentage of CD4+CD25+Foxp3+ regulatory T cells was lower in IRIS patients than in non-IRIS patients before HAART, 12 weeks after HAART, 24 weeks after HAART, and at the onset of IRIS. IL-2 and interferon (IFN)-γ levels were significantly higher at week 4 and at the onset of IRIS in IRIS patients than in non-IRIS patients. In contrast, IL-4 and IL-10 levels were significantly lower at week 4 and at the onset of IRIS in IRIS patients than in non-IRIS patients. Plasma IL-7 decreased gradually with the progression of HAART. The level of IL-7 was higher in IRIS patients than in non-IRIS patients at all follow-up time points. An imbalance of Th1/Th2 cytokines, a consistently low CD+CD25+Fox3+ percentage, and a high IL-7 level may be crucial in the pathogenesis of IRIS in AIDS patients who had received HAART. PMID:25131160

An automatic iris occlusion estimation method based on high-dimensional density estimation.

PubMed

Li, Yung-Hui; Savvides, Marios

2013-04-01

Iris masks play an important role in iris recognition. They indicate which part of the iris texture map is useful and which part is occluded or contaminated by noisy image artifacts such as eyelashes, eyelids, eyeglasses frames, and specular reflections. The accuracy of the iris mask is extremely important. The performance of the iris recognition system will decrease dramatically when the iris mask is inaccurate, even when the best recognition algorithm is used. Traditionally, people used the rule-based algorithms to estimate iris masks from iris images. However, the accuracy of the iris masks generated this way is questionable. In this work, we propose to use Figueiredo and Jain's Gaussian Mixture Models (FJ-GMMs) to model the underlying probabilistic distributions of both valid and invalid regions on iris images. We also explored possible features and found that Gabor Filter Bank (GFB) provides the most discriminative information for our goal. Finally, we applied Simulated Annealing (SA) technique to optimize the parameters of GFB in order to achieve the best recognition rate. Experimental results show that the masks generated by the proposed algorithm increase the iris recognition rate on both ICE2 and UBIRIS dataset, verifying the effectiveness and importance of our proposed method for iris occlusion estimation.

The fast iris image clarity evaluation based on Tenengrad and ROI selection

NASA Astrophysics Data System (ADS)

Gao, Shuqin; Han, Min; Cheng, Xu

2018-04-01

In iris recognition system, the clarity of iris image is an important factor that influences recognition effect. In the process of recognition, the blurred image may possibly be rejected by the automatic iris recognition system, which will lead to the failure of identification. Therefore it is necessary to evaluate the iris image definition before recognition. Considered the existing evaluation methods on iris image definition, we proposed a fast algorithm to evaluate the definition of iris image in this paper. In our algorithm, firstly ROI (Region of Interest) is extracted based on the reference point which is determined by using the feature of the light spots within the pupil, then Tenengrad operator is used to evaluate the iris image's definition. Experiment results show that, the iris image definition algorithm proposed in this paper could accurately distinguish the iris images of different clarity, and the algorithm has the merit of low computational complexity and more effectiveness.

A gallery approach for off-angle iris recognition

NASA Astrophysics Data System (ADS)

Karakaya, Mahmut; Yoldash, Rashiduddin; Boehnen, Christopher

2015-05-01

It has been proven that hamming distance score between frontal and off-angle iris images of same eye differs in iris recognition system. The distinction of hamming distance score is caused by many factors such as image acquisition angle, occlusion, pupil dilation, and limbus effect. In this paper, we first study the effect of the angle variations between iris plane and the image acquisition systems. We present how hamming distance changes for different off-angle iris images even if they are coming from the same iris. We observe that increment in acquisition angle of compared iris images causes the increment in hamming distance. Second, we propose a new technique in off-angle iris recognition system that includes creating a gallery of different off-angle iris images (such as, 0, 10, 20, 30, 40, and 50 degrees) and comparing each probe image with these gallery images. We will show the accuracy of the gallery approach for off-angle iris recognition.

Intercomparison Of Approaches For Modeling Second Order Ionospheric Corrections Using Gnss Measurements

NASA Astrophysics Data System (ADS)

Garcia Fernandez, M.; Butala, M.; Komjathy, A.; Desai, S. D.

2012-12-01

Correcting GNSS tracking data for the effects of second order ionospheric effects have been shown to cause a southward shift in GNSS-based precise point positioning solutions by as much as 10 mm, depending on the solar cycle conditions. The most commonly used approaches for modeling the higher order ionospheric effect include, (a) the use of global ionosphere maps to determine vertical total electron content (VTEC) and convert to slant TEC (STEC) assuming a thin shell ionosphere, and (b) using the dual-frequency measurements themselves to determine STEC. The latter approach benefits from not requiring ionospheric mapping functions between VTEC and STEC. However, this approach will require calibrations with receiver and transmitter Differential Code Biases (DCBs). We present results from comparisons of the two approaches. For the first approach, we also compare the use of VTEC observations from IONEX maps compared to climatological model-derived VTEC as provided by the International Reference Ionosphere (IRI2012). We consider various metrics to evaluate the relative performance of the different approaches, including station repeatability, GNSS-based reference frame recovery, and post-fit measurement residuals. Overall, the GIM-based approaches tend to provide lower noise in second order ionosphere correction and positioning solutions. The use of IONEX and IRI2012 models of VTEC provide similar results, especially in periods of low solar activity periods. The use of the IRI2012 model provides a convenient approach for operational scenarios by eliminating the dependence on routine updates of the GIMs, and also serves as a useful source of VTEC when IONEX maps may not be readily available.

Iris segmentation using an edge detector based on fuzzy sets theory and cellular learning automata.

PubMed

Ghanizadeh, Afshin; Abarghouei, Amir Atapour; Sinaie, Saman; Saad, Puteh; Shamsuddin, Siti Mariyam

2011-07-01

Iris-based biometric systems identify individuals based on the characteristics of their iris, since they are proven to remain unique for a long time. An iris recognition system includes four phases, the most important of which is preprocessing in which the iris segmentation is performed. The accuracy of an iris biometric system critically depends on the segmentation system. In this paper, an iris segmentation system using edge detection techniques and Hough transforms is presented. The newly proposed edge detection system enhances the performance of the segmentation in a way that it performs much more efficiently than the other conventional iris segmentation methods.

An Iris Segmentation Algorithm based on Edge Orientation for Off-angle Iris Recognition

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

Karakaya, Mahmut; Barstow, Del R; Santos-Villalobos, Hector J

Iris recognition is known as one of the most accurate and reliable biometrics. However, the accuracy of iris recognition systems depends on the quality of data capture and is negatively affected by several factors such as angle, occlusion, and dilation. In this paper, we present a segmentation algorithm for off-angle iris images that uses edge detection, edge elimination, edge classification, and ellipse fitting techniques. In our approach, we first detect all candidate edges in the iris image by using the canny edge detector; this collection contains edges from the iris and pupil boundaries as well as eyelash, eyelids, iris texturemore » etc. Edge orientation is used to eliminate the edges that cannot be part of the iris or pupil. Then, we classify the remaining edge points into two sets as pupil edges and iris edges. Finally, we randomly generate subsets of iris and pupil edge points, fit ellipses for each subset, select ellipses with similar parameters, and average to form the resultant ellipses. Based on the results from real experiments, the proposed method shows effectiveness in segmentation for off-angle iris images.« less

PLATEAU IRIS SYNDROME--CASE SERIES.

PubMed

Feraru, Crenguta Ioana; Pantalon, Anca Delia; Chiselita, Dorin; Branisteanu, Daniel

2015-01-01

Plateau iris is characterized by closing the anterior chamber angle due to a large ciliary body or due to its anterior insertion that alters the position of iris periphery in respect to the trabecular meshwork. There are two aspects that need to be differentiated: plateau iris configuration and plateau iris syndrome. The first describes a situation when the iris root is flat and the anterior chamber is not shallow, the latter refers to a post laser iridotomy condition in which a patent iridotomy has removed the relative pupillary block, but goniscopically confirmed angle closure recurs without central shallowing of the anterior chamber. Isolated plateau iris syndrome is rare compared to plateau iris configuration. We hereby present two case reports of plateau iris syndrome in young patients who came to an ophthalmologic consult by chance.

Iris texture traits show associations with iris color and genomic ancestry.

PubMed

Quillen, Ellen E; Guiltinan, Jenna S; Beleza, Sandra; Rocha, Jorge; Pereira, Rinaldo W; Shriver, Mark D

2011-01-01

This study seeks to identify associations among genomic biogeographic ancestry (BGA), quantitative iris color, and iris texture traits contributing to population-level variation in these phenotypes. DNA and iris photographs were collected from 300 individuals across three variably admixed populations (Portugal, Brazil, and Cape Verde). Two raters scored the photos for pigmentation spots, Fuchs' crypts, contraction furrows, and Wolflinn nodes. Iris color was quantified from RGB values. Maximum likelihood estimates of individual BGA were calculated from 176 ancestry informative markers. Pigmentation spots, Fuchs' crypts, contraction furrows, and iris color show significant positive correlation with increasing European BGA. Only contraction furrows are correlated with iris color. The relationship between BGA and iris texture illustrates a genetic contribution to this population-level variation. Copyright © 2011 Wiley-Liss, Inc.

The best bits in an iris code.

PubMed

Hollingsworth, Karen P; Bowyer, Kevin W; Flynn, Patrick J

2009-06-01

Iris biometric systems apply filters to iris images to extract information about iris texture. Daugman's approach maps the filter output to a binary iris code. The fractional Hamming distance between two iris codes is computed and decisions about the identity of a person are based on the computed distance. The fractional Hamming distance weights all bits in an iris code equally. However, not all the bits in an iris code are equally useful. Our research is the first to present experiments documenting that some bits are more consistent than others. Different regions of the iris are compared to evaluate their relative consistency, and contrary to some previous research, we find that the middle bands of the iris are more consistent than the inner bands. The inconsistent-bit phenomenon is evident across genders and different filter types. Possible causes of inconsistencies, such as segmentation, alignment issues, and different filters are investigated. The inconsistencies are largely due to the coarse quantization of the phase response. Masking iris code bits corresponding to complex filter responses near the axes of the complex plane improves the separation between the match and nonmatch Hamming distance distributions.

Immune reconstitution inflammatory syndrome associated with toxoplasmic encephalitis in HIV-infected patients.

PubMed

van Bilsen, Ward P H; van den Berg, Charlotte H S B; Rijnders, Bart J A; Brinkman, Kees; Mulder, Jan W; Gelinck, Luc B S; Hoepelman, Andy I M; Wit, Ferdinand W N M; van de Beek, Diederik; Prins, Jan M

2017-06-19

To investigate the incidence and risk factors of immune reconstitution inflammatory syndrome (IRIS) associated with toxoplasmic encephalitis (TE) in patients starting combination antiretroviral therapy (cART). A historical multicenter cohort study. We included all HIV-infected patients diagnosed with toxoplasmic encephalitis in six Dutch hospitals between 1996 and 2016. Diagnosis of TE-IRIS was made using predefined IRIS criteria. We distinguished paradoxical TE-IRIS (worsening of underlying treated infection) from unmasking TE-IRIS (unmasking of subclinical infection after start of cART). We compared CD4 cell count, plasma viral load and timing of cART initiation between patients with and without paradoxical TE-IRIS. A total of 211 toxoplasmic encephalitis cases were included. Among 143 cases at risk for paradoxical TE-IRIS, we identified five cases of paradoxical TE-IRIS (3.5%). In six other cases, we could not differentiate paradoxical TE-IRIS from recurrence of disease due to inadequate secondary Toxoplasma prophylaxis. There was no difference in time between start of toxoplasmic encephalitis treatment and cART initiation for patients who did or did not develop paradoxical TE-IRIS (P = 0.50). Within the group of 2228 patients who started cART while having a CD4 cell count below 200 × 10 cells/l and receiving adequate primary prophylaxis, we identified eight cases of unmasking TE-IRIS (0.36%). Unmasking TE-IRIS could not be differentiated from a newly occurring toxoplasmic encephalitis in six other patients, as they were not receiving adequate primary prophylaxis against Toxoplasma. Unmasking TE-IRIS was rare in this cohort, whereas paradoxical TE-IRIS did occur more often. We found no relationship between the timing of cART initiation and the occurrence of paradoxical TE-IRIS.

The International Reference Ionosphere - Climatological Standard for the Ionosphere

NASA Technical Reports Server (NTRS)

Bilitza, Dieter

2006-01-01

The International Reference Ionosphere (IRI) a joint project of URSI and COSPAR is the defacto standard for a climatological specification of ionospheric parameters. IRI is based on a wide range of ground and space data and has been steadily improved since its inception in 1969 with the ever-increasing volume of ionospheric data and with better mathematical descriptions of the observed global and temporal variation patterns. The IRI model has been validated with a large amount of data including data from the most recent ionospheric satellites (KOMPSAT, ROCSAT and TIMED) and data from global network of ionosondes. Several IRI teams are working on specific aspects of the IRI modeling effort including an improved representation of the topside ionosphere with a seamless transition to the plasmasphere, a new effort to represent the global variation of F2 peak parameters using the Neural Network (NN) technique, and the inclusion of several additional parameters in IRI, e.g., spread-F probability and ionospheric variability. Annual IRI workshops are the forum for discussions of these efforts and for all science activities related to IRI as well as applications of the IRI model in engineering and education. In this paper I will present a status report about the IRI effort with special emphasis on the presentations and results from the most recent IRI Workshops (Paris, 2004; Tortosa, 2005) and on the most important ongoing IRI activities. I will discuss the latest version of the IRI model, IRI-2006, highlighting the most recent changes and additions. Finally, the talk will review some of the applications of the IRI model with special emphasis on the use for radiowave propagation studies and communication purposes.

Association of iris surface features with iris parameters assessed by swept-source optical coherence tomography in Asian eyes.

PubMed

Tun, Tin A; Chua, Jacqueline; Shi, Yuan; Sidhartha, Elizabeth; Thakku, Sri Gowtham; Shei, William; Tan, Marcus Chiang Lee; Quah, Joanne Hui Min; Aung, Tin; Cheng, Ching-Yu

2016-12-01

To characterise the association of iris surface features (crypts, furrows and colour) with iris volume and curvature assessed by swept-source optical coherence tomography (SSOCT) in Asian eyes. Iris crypts (by number and size) and furrows (by number and circumferential extent) were graded from iris photographs. Iris colour was measured by a customised algorithm written on MATLAB (MathWorks, Natick, Massachusetts, USA). The iris was imaged by SSOCT (SS-1000, CASIA, Tomey, Nagoya, Japan). The associations of surface features with iris parameters were analysed using a generalised estimating equation. A total of 1704 subjects (3297 eyes) were included in the analysis. The majority was Chinese (86.4%), and 63.2% were females, and their mean age (±SD) was 61.4±6.6 years. After adjusting for age, sex, ethnicity, pupil size and corneal arcus, higher iris crypt grade was independently associated with smaller iris volume (β=-0.54, p<0.001), whereas darker irides and higher iris furrow grade were associated with larger iris volume (β=-0.041, p<0.001) and (β=0.233, p<0.001), respectively. Lighter coloured irides with more crypts and/or more furrows were also associated with less convexity (crypts: β=-0.003, p=0.03; furrows: β=-0.004, p=0.007; and colour: β=-0.001, p=0.005). Iris surface features were highly correlated with iris volume and curvature. Irides with more crypts have a smaller volume; and darker irides with more furrows have a larger volume. Lighter irides with more crypts and/or furrows have less convexity. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

ISO Technical Specification for the Ionosphere -IRI Recent Activities

NASA Astrophysics Data System (ADS)

Bilitza, Dieter; Reinisch, Bodo; Tamara, Gulyaeva

ISO Technical Specification TS 16457 recommends the International Reference Ionosphere (IRI) for the specification of ionospheric densities and temperatures. We review the latest develop-ments towards improving the IRI model and the newest version of the model IRI-2010. IRI-2010 includes several important improvements and additions. This presentation introduces these changes and discusses their benefits. The changes affect primarily the density profiles in the bottomside ionosphere and the density and height of the F2 peak, the point of highest density in the ionosphere. An important new addition to the model is the inclusion of auroral boundaries and their movement with magnetic activity. We will also discuss the status of other ongoing IRI activities and some of the recent applications of the IRI model. The homepage for the IRI project is at http://IRI.gsfc.nasa.gov/.

Activation of Ice Recrystallization Inhibition Activity of Poly(vinyl alcohol) using a Supramolecular Trigger.

PubMed

Phillips, Daniel J; Congdon, Thomas R; Gibson, Matthew I

2016-03-07

Antifreeze (glyco)proteins (AF(G)Ps) have potent ice recrystallisation inhibition (IRI) activity - a desirable phenomenon in applications such as cryopreservation, frozen food and more. In Nature AF(G)P activity is regulated by protein expression levels in response to an environmental stimulus; temperature. However, this level of regulation is not possible in synthetic systems. Here, a synthetic macromolecular mimic is introduced, using supramolecular assembly to regulate activity. Catechol-terminated poly(vinyl alcohol) was synthesised by RAFT polymerization. Upon addition of Fe 3+ , larger supramolecular star polymers form by assembly with two or three catechols. This increase in molecular weight effectively 'switches on' the IRI activity and is the first example of external control over the function of AFP mimetics. This provides a simple but elegant solution to the challenge of external control of AFP-mimetic function.

Optical Coherence Tomography Angiography Characteristics of Iris Melanocytic Tumors

PubMed Central

Skalet, Alison H.; Li, Yan; Lu, Chen D.; Jia, Yali; Lee, ByungKun; Husvogt, Lennart; Maier, Andreas; Fujimoto, James G.; Thomas, Charles R.; Huang, David

2016-01-01

Objective To evaluate tumor vasculature with optical coherence tomography (OCT) angiography (OCTA) in malignant iris melanomas and benign iris lesions. Design Cross-sectional observational clinical study. Participants Patients with iris lesions and healthy volunteers. Methods Eyes were imaged using OCTA systems operating at 1050 and 840 nm wavelengths. Three-dimensional OCTA scans were acquired. Iris melanomas patients treated with radiation therapy were imaged again after I-125 plaque brachytherapy at 6 and 18 months. Main Outcome Measures OCT and OCTA images, qualitative evaluation of iris and tumor vasculature and quantitative vessel density. Results One eye each of eight normal volunteers and nine patients with iris melanomas or benign iris lesions including freckles, nevi, and an iris pigment epithelial (IPE) cyst were imaged. The normal iris has radially-oriented vessels within the stroma on OCTA. Penetration of flow signal in normal iris depended on iris color, with best penetration seen in light to moderately pigmented irides. Iris melanomas demonstrated tortuous and disorganized intratumoral vasculature. In two eyes with nevi there was no increased vascularity; in another, fine vascular loops were noted near an area of ectropion uveae. Iris freckles and the IPE cyst did not have intrinsic vascularity. The vessel density was significantly higher within iris melanomas (34.5%±9.8%, p<0.05) than in benign iris nevi (8.0%±1.4%) or normal irides (8.0%±1.2%). Tumor regression after radiation therapy for melanomas was associated with decreased vessel density. OCTA at 1050 nm provided better visualization of tumor vasculature and penetration through thicker tumors than at 840 nm. But in very thick tumors and highly pigmented lesions even 1050 nm OCTA could not visualize their full thickness. Interpretable OCTA images were obtained in 82% participants in whom imaging was attempted. Conclusions This is the first demonstration of OCTA in iris tumors. OCTA may provide a dye-free, no-injection, cost-effective method for monitoring a variety of tumors including iris melanocytic lesions for growth and vascularity. This could be helpful in evaluating tumors for malignant transformation and response to treatment. Penetration of the OCT beam remains a limitation for highly pigmented tumors, as does the inability to image the entire iris in a single field. PMID:27856029

Optical Coherence Tomography Angiography Characteristics of Iris Melanocytic Tumors.

PubMed

Skalet, Alison H; Li, Yan; Lu, Chen D; Jia, Yali; Lee, ByungKun; Husvogt, Lennart; Maier, Andreas; Fujimoto, James G; Thomas, Charles R; Huang, David

2017-02-01

To evaluate tumor vasculature with optical coherence tomography angiography (OCTA) in malignant iris melanomas and benign iris lesions. Cross-sectional observational clinical study. Patients with iris lesions and healthy volunteers. Eyes were imaged using OCTA systems operating at 1050- and 840-nm wavelengths. Three-dimensional OCTA scans were acquired. Iris melanoma patients treated with radiation therapy were imaged again after I-125 plaque brachytherapy at 6 and 18 months. OCT and OCTA images, qualitative evaluation of iris and tumor vasculature, and quantitative vessel density. One eye each of 8 normal volunteers and 9 patients with iris melanomas or benign iris lesions, including freckles, nevi, and an iris pigment epithelial (IPE) cyst, were imaged. The normal iris has radially oriented vessels within the stroma on OCTA. Penetration of flow signal in normal iris depended on iris color, with best penetration seen in light to moderately pigmented irides. Iris melanomas demonstrated tortuous and disorganized intratumoral vasculature. In 2 eyes with nevi there was no increased vascularity; in another, fine vascular loops were noted near an area of ectropion uveae. Iris freckles and the IPE cyst did not have intrinsic vascularity. The vessel density was significantly higher within iris melanomas (34.5%±9.8%, P < 0.05) than in benign iris nevi (8.0%±1.4%) or normal irides (8.0%±1.2%). Tumor regression after radiation therapy for melanomas was associated with decreased vessel density. OCTA at 1050 nm provided better visualization of tumor vasculature and penetration through thicker tumors than at 840 nm. But in very thick tumors and highly pigmented lesions even 1050-nm OCTA could not visualize their full thickness. Interpretable OCTA images were obtained in 82% of participants in whom imaging was attempted. This is the first demonstration of OCTA in iris tumors. OCTA may provide a dye-free, no-injection, cost-effective method for monitoring a variety of tumors, including iris melanocytic lesions, for growth and vascularity. This could be helpful in evaluating tumors for malignant transformation and response to treatment. Penetration of the OCT beam remains a limitation for highly pigmented tumors, as does the inability to image the entire iris in a single field. Copyright © 2016 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

Improved Iris Recognition through Fusion of Hamming Distance and Fragile Bit Distance.

PubMed

Hollingsworth, Karen P; Bowyer, Kevin W; Flynn, Patrick J

2011-12-01

The most common iris biometric algorithm represents the texture of an iris using a binary iris code. Not all bits in an iris code are equally consistent. A bit is deemed fragile if its value changes across iris codes created from different images of the same iris. Previous research has shown that iris recognition performance can be improved by masking these fragile bits. Rather than ignoring fragile bits completely, we consider what beneficial information can be obtained from the fragile bits. We find that the locations of fragile bits tend to be consistent across different iris codes of the same eye. We present a metric, called the fragile bit distance, which quantitatively measures the coincidence of the fragile bit patterns in two iris codes. We find that score fusion of fragile bit distance and Hamming distance works better for recognition than Hamming distance alone. To our knowledge, this is the first and only work to use the coincidence of fragile bit locations to improve the accuracy of matches.

Clinicopathological correlates in HIV seropositive tuberculosis cases presenting with jaundice after initiating antiretroviral therapy with a structured review of the literature.

PubMed

Barr, David A; Ramdial, Pravistadevi K

2012-10-14

The development of jaundice after initiation of HAART in HIV-TB co-infected patients is a challenging presentation in resource constrained settings, and is often attributed to drug induced liver injury (DILI).Some investigators have described hepatic tuberculosis Immune Reconstitution Inflammatory Syndrome (TB-IRIS) as a cause of liver disease in patients initiating HAART, which could also cause jaundice. We report the clinical and histopathological features of five HIV-TB co-infected patients presenting with a syndrome of jaundice, tender hepatomegaly, bile canalicular enzyme rise and return of constitutional symptoms within 8 weeks of initiation of highly active antiretroviral therapy (HAART) for advanced HIV infection at a rural clinic in KwaZulu Natal, South Africa.All five patients had been diagnosed with tuberculosis infection prior to HAART initiation and were on antituberculous medication at time of developing jaundice. There was evidence of multiple aetiologies of liver injury in all patients. However, based on clinical course and pathological findings, predominant hepatic injury was thought to be drug induced in one case and hepatic tuberculosis associated immune reconstitution inflammatory syndrome (TB-IRIS) in the other four.In these later 4 patients, liver biopsy findings included necrotising and non-necrotising granulomatous inflammation in the lobules and portal tracts. The granulomas demonstrated - in addition to epithelioid histiocytes and Langhans giant cells - neutrophils, plasma cells and large numbers of lymphocytes, which are not features of a conventional untreated tuberculous response. In this high TB prevalent, low resource setting, TB-IRIS may be an important cause of jaundice post-HAART initiation. Clinicopathological correlation is essential for optimal diagnosis. Further multi-organ based histopathological studies in the context of immune reconstitution would be useful to clinicians in low resource settings dealing with this challenging presentation.

A young Botswana patient with congenital iris ectropion uvea.

PubMed

Shifa, Jemal Zeberga; Nkomazana, Othokawa; Bekele, Negussie Alula; Kassa, Mamo Woldu

2016-01-01

Congenital iris ectropion is a rare condition; non-progressive anomaly characterised by the presence of iris pigment epithelium on the anterior surface of the iris stroma and is frequently associated with anterior iris insertion, dysgenesis of the drainage angle and glaucoma. This paper describes unusual case of bilateral case of congenital iris ectropion in adult patient with pupillary abnormality, normal anterior chamber angle structure and with no evidence of glaucoma.

Relationship of the Van Herick Grading System with Peripheral Iris Configuration and Level of Iris Insertion.

PubMed

Khan, Faisal Aziz; Niazi, Shafaq Pervez Khan; Khan, Assad Zaman

2017-09-01

To determine the relationship of the van Herick angle grading system with the level of iris insertion and peripheral iris configuration. Observational study. Eye department, Combined Military Hospital, Malir Cantt., Karachi, from May to October 2015. Sixty-five eyes of 65 patients were recruited. Anterior chamber depth at the temporal limbus was measured as a fraction of corneal section thickness using van Herick technique and graded on the standard 4-point scale of the van Herick grading system. Gonioscopy of the temporal quadrant was performed with a Posner 4 mirror goniolens and both the true level of iris insertion and peripheral iris configuration were recorded on a 4-point scale so as to equate with the van Herick 4-point grading system. Spearman's rho test was applied to determine the relationship of the van Herick grading system with level of iris root insertion and peripheral iris configuration. Amoderate positive correlation between van Herick grade and peripheral iris configuration was found which was statistically significant (rs=0.42, p < 0.001). Astatistically significant and moderate positive correlation was also detected between van Herick grade and the level of iris insertion (rs=0.45, p < 0.001). The van Herick grade has a moderately positive relationship with the peripheral iris configuration and true level of iris insertion.

Monocyte Phenotype and IFN-γ-Inducible Cytokine Responses Are Associated with Cryptococcal Immune Reconstitution Inflammatory Syndrome

PubMed Central

Meya, David B.; Okurut, Samuel; Zziwa, Godfrey; Cose, Stephen; Bohjanen, Paul R.; Mayanja-Kizza, Harriet; Joloba, Moses; Boulware, David R.; Yukari Manabe, Carol; Wahl, Sharon; Janoff, Edward N.

2017-01-01

A third of adults with AIDS and cryptococcal meningitis (CM) develop immune reconstitution inflammatory syndrome (IRIS) after initiating antiretroviral therapy (ART), which is thought to result from exaggerated inflammatory antigen-specific T cell responses. The contribution of monocytes to the immunopathogenesis of cryptococcal IRIS remains unclear. We compared monocyte subset frequencies and immune responses in HIV-infected Ugandans at time of CM diagnosis (IRIS-Baseline) for those who later developed CM-IRIS, controls who did not develop CM-IRIS (Control-Baseline) at CM-IRIS (IRIS-Event), and for controls at a time point matched for ART duration (Control-Event) to understand the association of monocyte distribution and immune responses with cryptococcal IRIS. At baseline, stimulation with IFN-γ ex vivo induced a higher frequency of TNF-α- and IL-6-producing monocytes among those who later developed IRIS. Among participants who developed IRIS, ex vivo IFN-γ stimulation induced higher frequencies of activated monocytes, IL-6+, TNF-α+ classical, and IL-6+ intermediate monocytes compared with controls. In conclusion, we have demonstrated that monocyte subset phenotype and cytokine responses prior to ART are associated with and may be predictive of CM-IRIS. Larger studies to further delineate innate immunological responses and the efficacy of immunomodulatory therapies during cryptococcal IRIS are warranted. PMID:29371546

Development of the Informing Relatives Inventory (IRI): Assessing Index Patients' Knowledge, Motivation and Self-Efficacy Regarding the Disclosure of Hereditary Cancer Risk Information to Relatives.

PubMed

de Geus, Eveline; Aalfs, Cora M; Menko, Fred H; Sijmons, Rolf H; Verdam, Mathilde G E; de Haes, Hanneke C J M; Smets, Ellen M A

2015-08-01

Despite the use of genetic services, counselees do not always share hereditary cancer information with at-risk relatives. Reasons for not informing relatives may be categorized as a lack of: knowledge, motivation, and/or self-efficacy. This study aims to develop and test the psychometric properties of the Informing Relatives Inventory, a battery of instruments that intend to measure counselees' knowledge, motivation, and self-efficacy regarding the disclosure of hereditary cancer risk information to at-risk relatives. Guided by the proposed conceptual framework, existing instruments were selected and new instruments were developed. We tested the instruments' acceptability, dimensionality, reliability, and criterion-related validity in consecutive index patients visiting the Clinical Genetics department with questions regarding hereditary breast and/or ovarian cancer or colon cancer. Data of 211 index patients were included (response rate = 62%). The Informing Relatives Inventory (IRI) assesses three barriers in disclosure representing seven domains. Instruments assessing index patients' (positive) motivation and self-efficacy were acceptable and reliable and suggested good criterion-related validity. Psychometric properties of instruments assessing index patients knowledge were disputable. These items were moderately accepted by index patients and the criterion-related validity was weaker. This study presents a first conceptual framework and associated inventory (IRI) that improves insight into index patients' barriers regarding the disclosure of genetic cancer information to at-risk relatives. Instruments assessing (positive) motivation and self-efficacy proved to be reliable measurements. Measuring index patients knowledge appeared to be more challenging. Further research is necessary to ensure IRI's dimensionality and sensitivity to change.

IRIS TOXICOLOGICAL REVIEW AND SUMMARY DOCUMENTS FOR 2-HEXANONE

EPA Science Inventory

EPA will conduct an assessment of the noncancer health effects of 2-hexanone. The IRIS program will prepare an IRIS assessment for 2-hexanone. The IRIS assessment for 2-hexanone will consist of a Toxicological Review and an IRIS Summary. The Toxicological Review is a critical ...

Presentation Attack Detection for Iris Recognition System Using NIR Camera Sensor

PubMed Central

Nguyen, Dat Tien; Baek, Na Rae; Pham, Tuyen Danh; Park, Kang Ryoung

2018-01-01

Among biometric recognition systems such as fingerprint, finger-vein, or face, the iris recognition system has proven to be effective for achieving a high recognition accuracy and security level. However, several recent studies have indicated that an iris recognition system can be fooled by using presentation attack images that are recaptured using high-quality printed images or by contact lenses with printed iris patterns. As a result, this potential threat can reduce the security level of an iris recognition system. In this study, we propose a new presentation attack detection (PAD) method for an iris recognition system (iPAD) using a near infrared light (NIR) camera image. To detect presentation attack images, we first localized the iris region of the input iris image using circular edge detection (CED). Based on the result of iris localization, we extracted the image features using deep learning-based and handcrafted-based methods. The input iris images were then classified into real and presentation attack categories using support vector machines (SVM). Through extensive experiments with two public datasets, we show that our proposed method effectively solves the iris recognition presentation attack detection problem and produces detection accuracy superior to previous studies. PMID:29695113

Improving iris recognition performance using segmentation, quality enhancement, match score fusion, and indexing.

PubMed

Vatsa, Mayank; Singh, Richa; Noore, Afzel

2008-08-01

This paper proposes algorithms for iris segmentation, quality enhancement, match score fusion, and indexing to improve both the accuracy and the speed of iris recognition. A curve evolution approach is proposed to effectively segment a nonideal iris image using the modified Mumford-Shah functional. Different enhancement algorithms are concurrently applied on the segmented iris image to produce multiple enhanced versions of the iris image. A support-vector-machine-based learning algorithm selects locally enhanced regions from each globally enhanced image and combines these good-quality regions to create a single high-quality iris image. Two distinct features are extracted from the high-quality iris image. The global textural feature is extracted using the 1-D log polar Gabor transform, and the local topological feature is extracted using Euler numbers. An intelligent fusion algorithm combines the textural and topological matching scores to further improve the iris recognition performance and reduce the false rejection rate, whereas an indexing algorithm enables fast and accurate iris identification. The verification and identification performance of the proposed algorithms is validated and compared with other algorithms using the CASIA Version 3, ICE 2005, and UBIRIS iris databases.

Presentation Attack Detection for Iris Recognition System Using NIR Camera Sensor.

PubMed

Nguyen, Dat Tien; Baek, Na Rae; Pham, Tuyen Danh; Park, Kang Ryoung

2018-04-24

Among biometric recognition systems such as fingerprint, finger-vein, or face, the iris recognition system has proven to be effective for achieving a high recognition accuracy and security level. However, several recent studies have indicated that an iris recognition system can be fooled by using presentation attack images that are recaptured using high-quality printed images or by contact lenses with printed iris patterns. As a result, this potential threat can reduce the security level of an iris recognition system. In this study, we propose a new presentation attack detection (PAD) method for an iris recognition system (iPAD) using a near infrared light (NIR) camera image. To detect presentation attack images, we first localized the iris region of the input iris image using circular edge detection (CED). Based on the result of iris localization, we extracted the image features using deep learning-based and handcrafted-based methods. The input iris images were then classified into real and presentation attack categories using support vector machines (SVM). Through extensive experiments with two public datasets, we show that our proposed method effectively solves the iris recognition presentation attack detection problem and produces detection accuracy superior to previous studies.

IRIS COLOUR CLASSIFICATION SCALES – THEN AND NOW

PubMed Central

Grigore, Mariana; Avram, Alina

2015-01-01

Eye colour is one of the most obvious phenotypic traits of an individual. Since the first documented classification scale developed in 1843, there have been numerous attempts to classify the iris colour. In the past centuries, iris colour classification scales has had various colour categories and mostly relied on comparison of an individual’s eye with painted glass eyes. Once photography techniques were refined, standard iris photographs replaced painted eyes, but this did not solve the problem of painted/ printed colour variability in time. Early clinical scales were easy to use, but lacked objectivity and were not standardised or statistically tested for reproducibility. The era of automated iris colour classification systems came with the technological development. Spectrophotometry, digital analysis of high-resolution iris images, hyper spectral analysis of the human real iris and the dedicated iris colour analysis software, all accomplished an objective, accurate iris colour classification, but are quite expensive and limited in use to research environment. Iris colour classification systems evolved continuously due to their use in a wide range of studies, especially in the fields of anthropology, epidemiology and genetics. Despite the wide range of the existing scales, up until present there has been no generally accepted iris colour classification scale. PMID:27373112

IRIS COLOUR CLASSIFICATION SCALES--THEN AND NOW.

PubMed

Grigore, Mariana; Avram, Alina

2015-01-01

Eye colour is one of the most obvious phenotypic traits of an individual. Since the first documented classification scale developed in 1843, there have been numerous attempts to classify the iris colour. In the past centuries, iris colour classification scales has had various colour categories and mostly relied on comparison of an individual's eye with painted glass eyes. Once photography techniques were refined, standard iris photographs replaced painted eyes, but this did not solve the problem of painted/ printed colour variability in time. Early clinical scales were easy to use, but lacked objectivity and were not standardised or statistically tested for reproducibility. The era of automated iris colour classification systems came with the technological development. Spectrophotometry, digital analysis of high-resolution iris images, hyper spectral analysis of the human real iris and the dedicated iris colour analysis software, all accomplished an objective, accurate iris colour classification, but are quite expensive and limited in use to research environment. Iris colour classification systems evolved continuously due to their use in a wide range of studies, especially in the fields of anthropology, epidemiology and genetics. Despite the wide range of the existing scales, up until present there has been no generally accepted iris colour classification scale.

Iris Recognition Using Feature Extraction of Box Counting Fractal Dimension

NASA Astrophysics Data System (ADS)

Khotimah, C.; Juniati, D.

2018-01-01

Biometrics is a science that is now growing rapidly. Iris recognition is a biometric modality which captures a photo of the eye pattern. The markings of the iris are distinctive that it has been proposed to use as a means of identification, instead of fingerprints. Iris recognition was chosen for identification in this research because every human has a special feature that each individual is different and the iris is protected by the cornea so that it will have a fixed shape. This iris recognition consists of three step: pre-processing of data, feature extraction, and feature matching. Hough transformation is used in the process of pre-processing to locate the iris area and Daugman’s rubber sheet model to normalize the iris data set into rectangular blocks. To find the characteristics of the iris, it was used box counting method to get the fractal dimension value of the iris. Tests carried out by used k-fold cross method with k = 5. In each test used 10 different grade K of K-Nearest Neighbor (KNN). The result of iris recognition was obtained with the best accuracy was 92,63 % for K = 3 value on K-Nearest Neighbor (KNN) method.

Accurate Iris Recognition at a Distance Using Stabilized Iris Encoding and Zernike Moments Phase Features.

PubMed

Tan, Chun-Wei; Kumar, Ajay

2014-07-10

Accurate iris recognition from the distantly acquired face or eye images requires development of effective strategies which can account for significant variations in the segmented iris image quality. Such variations can be highly correlated with the consistency of encoded iris features and the knowledge that such fragile bits can be exploited to improve matching accuracy. A non-linear approach to simultaneously account for both local consistency of iris bit and also the overall quality of the weight map is proposed. Our approach therefore more effectively penalizes the fragile bits while simultaneously rewarding more consistent bits. In order to achieve more stable characterization of local iris features, a Zernike moment-based phase encoding of iris features is proposed. Such Zernike moments-based phase features are computed from the partially overlapping regions to more effectively accommodate local pixel region variations in the normalized iris images. A joint strategy is adopted to simultaneously extract and combine both the global and localized iris features. The superiority of the proposed iris matching strategy is ascertained by providing comparison with several state-of-the-art iris matching algorithms on three publicly available databases: UBIRIS.v2, FRGC, CASIA.v4-distance. Our experimental results suggest that proposed strategy can achieve significant improvement in iris matching accuracy over those competing approaches in the literature, i.e., average improvement of 54.3%, 32.7% and 42.6% in equal error rates, respectively for UBIRIS.v2, FRGC, CASIA.v4-distance.

A novel iris patterns matching algorithm of weighted polar frequency correlation

NASA Astrophysics Data System (ADS)

Zhao, Weijie; Jiang, Linhua

2014-11-01

Iris recognition is recognized as one of the most accurate techniques for biometric authentication. In this paper, we present a novel correlation method - Weighted Polar Frequency Correlation(WPFC) - to match and evaluate two iris images, actually it can also be used for evaluating the similarity of any two images. The WPFC method is a novel matching and evaluating method for iris image matching, which is complete different from the conventional methods. For instance, the classical John Daugman's method of iris recognition uses 2D Gabor wavelets to extract features of iris image into a compact bit stream, and then matching two bit streams with hamming distance. Our new method is based on the correlation in the polar coordinate system in frequency domain with regulated weights. The new method is motivated by the observation that the pattern of iris that contains far more information for recognition is fine structure at high frequency other than the gross shapes of iris images. Therefore, we transform iris images into frequency domain and set different weights to frequencies. Then calculate the correlation of two iris images in frequency domain. We evaluate the iris images by summing the discrete correlation values with regulated weights, comparing the value with preset threshold to tell whether these two iris images are captured from the same person or not. Experiments are carried out on both CASIA database and self-obtained images. The results show that our method is functional and reliable. Our method provides a new prospect for iris recognition system.

Immunopathology of immune reconstitution inflammatory syndrome in Whipple's disease.

PubMed

Moos, Verena; Feurle, Gerhard E; Schinnerling, Katina; Geelhaar, Anika; Friebel, Julian; Allers, Kristina; Moter, Annette; Kikhney, Judith; Loddenkemper, Christoph; Kühl, Anja A; Erben, Ulrike; Fenollar, Florence; Raoult, Didier; Schneider, Thomas

2013-03-01

During antimicrobial treatment of classic Whipple's disease (CWD), the chronic systemic infection with Tropheryma whipplei, immune reconstitution inflammatory syndrome (IRIS), is a serious complication. The aim of our study was to characterize the immunological processes underlying IRIS in CWD. Following the definition of IRIS, we describe histological features of IRIS and immunological parameters of 24 CWD IRIS patients, 189 CWD patients without IRIS, and 89 healthy individuals. T cell reconstitution, Th1 reactivity, and the phenotype of T cells were described in the peripheral blood, and infiltration of CD4(+) T cells and regulatory T cells in the duodenal mucosa was determined. During IRIS, tissues were heavily infiltrated by CD3(+), predominantly CD45RO(+)CD4(+) T cells. In the periphery, initial reduction of CD4(+) cell counts and their reconstitution on treatment was more pronounced in CWD patients with IRIS than in those without IRIS. The ratio of activated and regulatory CD4(+) T cells, nonspecific Th1 reactivity, and the proportion of naive among CD4(+) T cells was high, whereas serum IL-10 was low during IRIS. T. whipplei-specific Th1 reactivity remained suppressed before and after emergence of IRIS. The findings that IRIS in CWD mainly are mediated by nonspecific activation of CD4(+) T cells and that it is not sufficiently counterbalanced by regulatory T cells indicate that flare-up of pathogen-specific immunoreactivity is not instrumental in the pathogenesis of IRIS in CWD.

Incidence and Predictors of Immune Reconstitution Inflammatory Syndrome in a Rural Area of Mozambique

PubMed Central

Letang, Emilio; Miró, José M.; Nhampossa, Tacilta; Ayala, Edgar; Gascon, Joaquim; Menéndez, Clara; Alonso, Pedro L.; Naniche, Denise

2011-01-01

Background There is limited data on the epidemiology of Immune Reconstitution Inflammatory Syndrome (IRIS) in rural sub-Saharan Africa. A prospective observational cohort study was conducted to assess the incidence, clinical characteristics, outcome and predictors of IRIS in rural Mozambique. Methods One hundred and thirty-six consecutive antiretroviral treatment (ART)-naïve HIV-1-infected patients initiating ART at the Manhiça district hospital were prospectively followed for development of IRIS over 16 months. Survival analysis by Cox regression was performed to identify pre-ART predictors of IRIS development. Results Thirty-six patients developed IRIS [26.5%, incidence rate 3.1 cases/100 persons-month of ART (95% CI 2.2–4.3)]. Median time to IRIS onset was 62 days from ART initiation (IQR 35.5–93.5). Twenty-five cases (69.4%) were “unmasking”, 10 (27.8%) were “paradoxical”, and 1 (2.8%) developed a paradoxical worsening followed by the unmasking of another condition. Systemic OI (OI-IRIS) accounted for 47% (17/36) of IRIS cases, predominantly of KS (8 cases) and TB (6 cases) IRIS. Mucocutaneous IRIS manifestations (MC-IRIS) accounted for 53% (19/36) of IRIS events, mostly tinea (9 cases) and herpes simplex infection (3 cases). Multivariate analysis identified two independent predictors of IRIS development: pre-ART CD4 count <50 cells/µl (HR 2.3, 95% CI 1.19–4.44, p = 0.01) and body mass index (BMI) <18.5 (HR 2.15, 95% CI 1.07–4.3, p = 0.03). The pre-cART proportion of activated T-cells, as well as the immunologic and virologic response to ART were not associated with IRIS development. All patients continued on ART, 7 (19.4%) required hospitalization and there were 3 deaths (8.3%) attributable to IRIS. Conclusions IRIS is common in patients initiating ART in rural Mozambique. Pre-ART CD4 counts and BMI can easily be assessed at ART initiation in rural sub-Saharan Africa to identify patients at high risk of IRIS, for whom close supervision is warranted. PMID:21386993

Alouette and ISIS topside sounder measurements -A data source for improvements of the IRI model in the topside ionosphere

NASA Astrophysics Data System (ADS)

Bilitza, Dieter; Benson, Robert; Reinisch, Bodo; Huang, Xueqin

The Alouette and ISIS topside sounder satellites recorded a great wealth of information about the topside ionosphere during their long period of operations (from 1962 to 1990). So much though that only a small percentage was analyzed during the mission life time. The soundings were stored on more than 100,000 seven-track analog telemetry tapes. In the mid-nineties space limitations and storage costs threatened an imminent loss of these tapes. Only a last minute intervention spear-headed by NASA's Ionosphere, Thermosphere, Mesosphere (ITM) Data Evaluation Panel saved a significant portion of these tapes and with funding from the AISRP program these data were first digitized and then converted into electron density profiles. This data restoration effort more than tripled the Alouette/ISIS topside sounder data base and has led to significant improvements of models for the topside ionosphere, e.g., about a factor of 2 improvement in the case of the IRI-2007 topside electron density profile. We will present a brief history of this successful data restoration effort and its current status. The homepage for the ISIS project is at http://nssdc.gsfc.nasa.gov/space/isis/isis-status.html.

Effect of iris registration on outcomes of FEMTOLASIK for myopia and myopic astigmatism.

PubMed

Ghoreishi, Mohammad; Beni, Zahra Naderi; Beni, Afsaneh Naderi; Kianersi, Farzan

2017-09-05

To compare the visual and refractive outcomes after FEMTOLASIK with and without iris registration. In this randomized, prospective, comparative, contralateral eye study, 118 eyes of 59 patients with myopia and myopic astigmatism underwent LASIK using the Femto LDV femtosecond laser (160 µm) and the MEL80 with or without iris registration. For each patient, iris registration FEMTOLASIK was performed on one eye and non-iris registration FEMTOLASIK was performed on the other eye, assigned at random. Patients were evaluated before and 12 months. Uncorrected visual acuity, best-corrected visual acuity, manifest refraction, contrast sensitivity, and higher-order aberrations (HOAs) were evaluated. At 12 months, the mean UDVA was 0.002 ± 0.07 logMAR (20/19) in iris registration eyes and 0.00 ± 0.06 logMAR (20/24) in non-iris registration eyes (P = 0.9). 61% of iris registration eyes and 71.2% of non-iris registration eyes achieved a UDVA of 20/20 or better (P = 0.31); 98.3% of eyes with the iris registration FEMTOLASIK and 94.9% with the non-iris registration FEMTOLASIK were within ±0.50 D from emmetropia (P = 0.71). No statistically significant difference was found in postoperative contrast sensitivity between groups at 3, 6, 12, or 18 cycles/degree (P > 0.05). There was significant increase in total HOA root mean square in two groups. The mean error magnitude of surgically induced astigmatism 12 months postoperatively was -0.33 in iris registration eyes and -0.24 in the non-iris registration eyes (P = 0.36). FEMTOLASIK with and without iris registration provides similar results in myopic and myopic astigmatism patients.

Steatotic livers are susceptible to normothermic ischemia-reperfusion injury from mitochondrial Complex-I dysfunction

PubMed Central

Chu, Michael JJ; Premkumar, Rakesh; Hickey, Anthony JR; Jiang, Yannan; Delahunt, Brett; Phillips, Anthony RJ; Bartlett, Adam SJR

2016-01-01

AIM: To assess the effects of ischemic preconditioning (IPC, 10-min ischemia/10-min reperfusion) on steatotic liver mitochondrial function after normothermic ischemia-reperfusion injury (IRI). METHODS: Sixty male Sprague-Dawley rats were fed 8-wk with either control chow or high-fat/high-sucrose diet inducing > 60% mixed steatosis. Three groups (n = 10/group) for each dietary state were tested: (1) the IRI group underwent 60 min partial hepatic ischemia and 4 h reperfusion; (2) the IPC group underwent IPC prior to same standard IRI; and (3) sham underwent the same surgery without IRI or IPC. Hepatic mitochondrial function was analyzed by oxygraphs. Mitochondrial Complex-I, Complex-II enzyme activity, serum alanine aminotransferase (ALT), and histological injury were measured. RESULTS: Steatotic-IRI livers had a greater increase in ALT (2476 ± 166 vs 1457 ± 103 IU/L, P < 0.01) and histological injury following IRI compared to the lean liver group. Steatotic-IRI demonstrated lower Complex-I activity at baseline [78.4 ± 2.5 vs 116.4 ± 6.0 nmol/(min.mg protein), P < 0.001] and following IRI [28.0 ± 6.2 vs 104.3 ± 12.6 nmol/(min.mg protein), P < 0.001]. Steatotic-IRI also demonstrated impaired Complex-I function post-IRI compared to the lean liver IRI group. Complex-II activity was unaffected by hepatic steatosis or IRI. Lean liver mitochondrial function was unchanged following IRI. IPC normalized ALT and histological injury in steatotic livers but had no effect on overall steatotic liver mitochondrial function or individual mitochondrial complex enzyme activities. CONCLUSION: Warm IRI impairs steatotic liver Complex-I activity and function. The protective effects of IPC in steatotic livers may not be mediated through mitochondria. PMID:27217699

IRIS Toxicological Review and Summary Documents for N ...

EPA Pesticide Factsheets

EPA's assessment of the noncancer health effects and carcinogenic potential of n-hexane was last prepared and added to the IRIS data base in 1990. The IRIS program is updating the IRIS assessment for n-hexane; this update will incorporate health effects information published since the last assessment was prepared as well as new risk assessment methods. The IRIS assessment for n-hexane will consist of a Toxicological Review and IRIS Summary. The Toxicological Review is a critical review of the physicochemical and toxicokinetic properties of the chemical and its toxicity in humans and experimental systems. The assessment will present reference values for noncancer effects of n-hexane (RfD and RfC) and a cancer assessment, where supported by available data. The Toxicological Review and IRIS Summary will be subject to internal peer consultation, Agency review, and external scientific peer review. EPA is undertaking an update of the Integrated Risk Information System (IRIS) health assessment for n-hexane. The outcome of this project is an updated Toxicological Review and IRIS Summary for n-Hexane that will be entered into the IRIS database. IRIS is an EPA data base containing Agency scientific positions on potential adverse human health effects that may result from chronic (or lifetime) exposure to chemicals in the environment. IRIS contains chemical-specific summaries of qualitative and quantitative health information in support of two steps of the risk assessment

A Statistical Analysis of IrisCode and Its Security Implications.

PubMed

Kong, Adams Wai-Kin

2015-03-01

IrisCode has been used to gather iris data for 430 million people. Because of the huge impact of IrisCode, it is vital that it is completely understood. This paper first studies the relationship between bit probabilities and a mean of iris images (The mean of iris images is defined as the average of independent iris images.) and then uses the Chi-square statistic, the correlation coefficient and a resampling algorithm to detect statistical dependence between bits. The results show that the statistical dependence forms a graph with a sparse and structural adjacency matrix. A comparison of this graph with a graph whose edges are defined by the inner product of the Gabor filters that produce IrisCodes shows that partial statistical dependence is induced by the filters and propagates through the graph. Using this statistical information, the security risk associated with two patented template protection schemes that have been deployed in commercial systems for producing application-specific IrisCodes is analyzed. To retain high identification speed, they use the same key to lock all IrisCodes in a database. The belief has been that if the key is not compromised, the IrisCodes are secure. This study shows that even without the key, application-specific IrisCodes can be unlocked and that the key can be obtained through the statistical dependence detected.

IRIS TOXICOLOGICAL REVIEW AND SUMMARY DOCUMENTS FOR 1,1,1-TRICHLOROETHANE (PEER REVIEW PLAN)

EPA Science Inventory

EPA's assessment of the carcinogenic potential of 1,1,1-trichloroethane was entered into the IRIS database in 1988, and the assessment of noncancer effects following oral exposure was withdrawn from IRIS in 1991. The IRIS program prepared an update of the IRIS assessment for 1,1,...

Iris double recognition based on modified evolutionary neural network

NASA Astrophysics Data System (ADS)

Liu, Shuai; Liu, Yuan-Ning; Zhu, Xiao-Dong; Huo, Guang; Liu, Wen-Tao; Feng, Jia-Kai

2017-11-01

Aiming at multicategory iris recognition under illumination and noise interference, this paper proposes a method of iris double recognition based on a modified evolutionary neural network. An equalization histogram and Laplace of Gaussian operator are used to process the iris to suppress illumination and noise interference and Haar wavelet to convert the iris feature to binary feature encoding. Calculate the Hamming distance for the test iris and template iris , and compare with classification threshold, determine the type of iris. If the iris cannot be identified as a different type, there needs to be a secondary recognition. The connection weights in back-propagation (BP) neural network use modified evolutionary neural network to adaptively train. The modified neural network is composed of particle swarm optimization with mutation operator and BP neural network. According to different iris libraries in different circumstances of experimental results, under illumination and noise interference, the correct recognition rate of this algorithm is higher, the ROC curve is closer to the coordinate axis, the training and recognition time is shorter, and the stability and the robustness are better.

Ordinal measures for iris recognition.

PubMed

Sun, Zhenan; Tan, Tieniu

2009-12-01

Images of a human iris contain rich texture information useful for identity authentication. A key and still open issue in iris recognition is how best to represent such textural information using a compact set of features (iris features). In this paper, we propose using ordinal measures for iris feature representation with the objective of characterizing qualitative relationships between iris regions rather than precise measurements of iris image structures. Such a representation may lose some image-specific information, but it achieves a good trade-off between distinctiveness and robustness. We show that ordinal measures are intrinsic features of iris patterns and largely invariant to illumination changes. Moreover, compactness and low computational complexity of ordinal measures enable highly efficient iris recognition. Ordinal measures are a general concept useful for image analysis and many variants can be derived for ordinal feature extraction. In this paper, we develop multilobe differential filters to compute ordinal measures with flexible intralobe and interlobe parameters such as location, scale, orientation, and distance. Experimental results on three public iris image databases demonstrate the effectiveness of the proposed ordinal feature models.

Multiple local feature representations and their fusion based on an SVR model for iris recognition using optimized Gabor filters

NASA Astrophysics Data System (ADS)

He, Fei; Liu, Yuanning; Zhu, Xiaodong; Huang, Chun; Han, Ye; Dong, Hongxing

2014-12-01

Gabor descriptors have been widely used in iris texture representations. However, fixed basic Gabor functions cannot match the changing nature of diverse iris datasets. Furthermore, a single form of iris feature cannot overcome difficulties in iris recognition, such as illumination variations, environmental conditions, and device variations. This paper provides multiple local feature representations and their fusion scheme based on a support vector regression (SVR) model for iris recognition using optimized Gabor filters. In our iris system, a particle swarm optimization (PSO)- and a Boolean particle swarm optimization (BPSO)-based algorithm is proposed to provide suitable Gabor filters for each involved test dataset without predefinition or manual modulation. Several comparative experiments on JLUBR-IRIS, CASIA-I, and CASIA-V4-Interval iris datasets are conducted, and the results show that our work can generate improved local Gabor features by using optimized Gabor filters for each dataset. In addition, our SVR fusion strategy may make full use of their discriminative ability to improve accuracy and reliability. Other comparative experiments show that our approach may outperform other popular iris systems.

Effects of Iris Surface Curvature on Iris Recognition

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

Thompson, Joseph T; Flynn, Patrick J; Bowyer, Kevin W

To focus on objects at various distances, the lens of the eye must change shape to adjust its refractive power. This change in lens shape causes a change in the shape of the iris surface which can be measured by examining the curvature of the iris. This work isolates the variable of iris curvature in the recognition process and shows that differences in iris curvature degrade matching ability. To our knowledge, no other work has examined the effects of varying iris curvature on matching ability. To examine this degradation, we conduct a matching experiment across pairs of images with varyingmore » degrees of iris curvature differences. The results show a statistically signi cant degradation in matching ability. Finally, the real world impact of these ndings is discussed« less

IRIS Toxicological Review of Benzo[a]pyrene (Interagency ...

EPA Pesticide Factsheets

In January 2017, EPA finalized the IRIS assessment of Benzo[a]pyrene. The Toxicological Review was reviewed internally by EPA and by other federal agencies and White House Offices before public release. Consistent with the May 2009 IRIS assessment development process, all written comments on IRIS assessments submitted by other federal agencies and White House Offices are made publicly available. Accordingly, interagency comments and the interagency science discussion materials provided to other agencies, including interagency review drafts of the IRIS Toxicological Review of Benzo[a]pyrene are posted on this site. EPA is undertaking an update of the Integrated Risk Information System (IRIS) health assessment for benzo[a]pyrene (BaP). The outcome of this project is an updated Toxicological Review and IRIS Summary for BaP that will be entered into the IRIS database.

The International Reference Ionosphere Today and in the Future

NASA Technical Reports Server (NTRS)

Bilitza, Dieter; McKinnell, Lee-Ane; Reinisch, Bodo; Fuller-Rowell,Tim

2010-01-01

The international reference ionosphere (IRI) is the internationally recognized and recommended standard for the specification of plasma parameters in Earth's ionosphere. It describes monthly averages of electron density, electron temperature, ion temperature, ion composition, and several additional parameters in the altitude range from 60 to 1,500 km. A joint working group of the Committee on Space Research (COSPAR) and the International Union of Radio Science (URSI) is in charge of developing and improving the IRI model. As requested by COSPAR and URSI, IRI is an empirical model being based on most of the available and reliable data sources for the ionospheric plasma. The paper describes the latest version of the model and reviews efforts towards future improvements, including the development of new global models for the F2 peak density and height, and a new approach to describe the electron density in the topside and plasmasphere. Our emphasis will be on the electron density because it is the IRI parameter most relevant to geodetic techniques and studies. Annual IRI meetings are the main venue for the discussion of IRI activities, future improvements, and additions to the model. A new special IRI task force activity is focusing on the development of a real-time IRI (RT-IRI) by combining data assimilation techniques with the IRI model. A first RT-IRI task force meeting was held in 2009 in Colorado Springs. We will review the outcome of this meeting and the plans for the future. The IRI homepage is at http://www.IRI.gsfc.nasa.gov

Lattice-like collagen fiber meshwork in the iris stroma of the cat: a possible mechanism to generate the tension directed towards the iris root which is required for pupillary dilatation in the sympathectomized eye.

PubMed

Sakuraba, M; Yun, S; Ichinohe, N; Yonekura, H; Shoumura, K

1999-10-01

NaOH digestion technique for collagen fiber dissection and scanning electron microscopy demonstrated a lattice-like meshwork in the anterior surface of the iris stroma of the cat. The mesh threads were made of collagen fibril bundles. In the constricted pupil, the meshes were square to rhomboid with the diagonals in the direction of the radius or circumference of the iris. In the dilated pupil, however, the meshes were strongly flattened rhomboid or ellipse with a longer diagnoal or axis in the circumferential direction. At the mesh corners facing the pupillary margin or the iris root, the collagen fibril bundles were strongly bent in the iris of the constricted pupil, while they were almost straight or slightly wavy in the iris of the dilated pupil. Accumulation of elasticity tension generated by this small distortion of the iris-mesh threads in the constricted pupil was considered to generate a tension directed towards the iris root, which is required for pupillary dilatation in the sympathectomized eye. On the posterior surface of the iris stroma, numerous thin pleats tightly woven with collagen fibrils traversed straightway through the radial length of the ciliary zone of the iris in both constricted and dilated pupils. The structural changes of these pleats in miosis and mydriasis were very small compared with the meshwork of the anterior aspect of the iris. Therefore, they were considered to work mainly as an iris skeleton.

IRIS Toxicological Review of Hexahydro-1,3,5-Trinitro-1,3,5 ...

EPA Pesticide Factsheets

EPA is developing an Integrated Risk Information System (IRIS) assessment of hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) and has released the draft assessment for public comment. When final, the assessment will appear on the IRIS database. EPA is undertaking an update of the Integrated Risk Information System (IRIS) health assessment for RDX. The outcome of this project is an updated Toxicological Review and IRIS Summary for RDX that will be entered into the IRIS database.

IRIS Toxicological Review of Benzo[a]pyrene (Public ...

EPA Pesticide Factsheets

EPA is developing an Integrated Risk Information System (IRIS) assessment of benzo[a]pyrene and has released the draft assessment for public comment and external peer review. When final, the assessment will appear on the IRIS database. EPA is undertaking an update of the Integrated Risk Information System (IRIS) health assessment for benzo[a]pyrene (BaP). The outcome of this project is an updated Toxicological Review and IRIS Summary for BaP that will be entered into the IRIS database.

A novel iris localization algorithm using correlation filtering

NASA Astrophysics Data System (ADS)

Pohit, Mausumi; Sharma, Jitu

2015-06-01

Fast and efficient segmentation of iris from the eye images is a primary requirement for robust database independent iris recognition. In this paper we have presented a new algorithm for computing the inner and outer boundaries of the iris and locating the pupil centre. Pupil-iris boundary computation is based on correlation filtering approach, whereas iris-sclera boundary is determined through one dimensional intensity mapping. The proposed approach is computationally less extensive when compared with the existing algorithms like Hough transform.

IRIS Toxicological Review of Tert-Butyl Alcohol (Tert-Butanol) ...

EPA Pesticide Factsheets

On April 29, 2016, the Toxicological Review of tert-Butyl Alcohol (tert-Butanol) (Public Comment Draft) was released for public comment. The draft Toxicological Review and charge were reviewed internally by EPA and by other federal agencies and the Executive Office of the President during Step 3 (Interagency Science Consultation) before public release. As part of the IRIS process, all written interagency comments on IRIS assessments will be made publicly available. Accordingly, interagency comments with EPA's response and the interagency science consultation drafts of the IRIS Toxicological Review of tert-Butanol and charge to external peer reviewers are posted on this site. EPA is undertaking a new health assessment for t-butyl alcohol (tert-butanol) for the Integrated Risk Information System (IRIS). The outcome of this project will be a Toxicological Review and IRIS and IRIS Summary of TBA that will be entered on the IRIS database. IRIS is an EPA database containing Agency scientific positions on potential adverse human health effects that may result from chronic (or lifetime) exposure to chemicals in the environment. IRIS contains chemical-specific summaries of qualitative and quantitative health information to evaluate potential public health risks associated with environmental contaminants. The IRIS database is relied on for the development of risk assessments, site-specific environmental decisions, and rule making.

IRIS Toxicological Review of Ethyl Tertiary Butyl Ether (Etbe) ...

EPA Pesticide Factsheets

In September 2016, EPA released the draft IRIS Toxicological Review of Ethyl Tertiary Butyl Ether (ETBE) for public comment and discussion. The draft assessment was reviewed internally by EPA and by other federal agencies and White House Offices before public release. Consistent with the May 2009 IRIS assessment development process, all written comments on IRIS assessments submitted by other federal agencies and White House Offices are made publicly available. Accordingly, interagency comments and the interagency science consultation materials provided to other agencies, including interagency review drafts of the IRIS Toxicological Review of Ethyl Tertiary Butyl Ether are posted on this site. EPA is undertaking an new health assessment for ethyl tertiary butyl ether (ETBE) for the Integrated Risk Information System (IRIS). The outcome of this project will be a Toxicological Review and IRIS Summary of ETBE that will be entered on the IRIS database. IRIS is an EPA database containing Agency scientific positions on potential adverse human health effects that may result from chronic (or lifetime) exposure to chemicals in the environment. IRIS contains chemical-specific summaries of qualitative and quantitative health information in support of two steps of the risk assessment process, i.e., hazard identification and dose-response evaluation. IRIS assessments are used nationally and internationally in combination with specific situational exposure assessment infor

IRIS Toxicological Review of Biphenyl (Interagency Science ...

EPA Pesticide Factsheets

On September 30, 2011, the draft Toxicological Review of Biphenyl and the charge to external peer reviewers were released for external peer review and public comment. The Toxicological Review and charge were reviewed internally by EPA and by other federal agencies and White House Offices before public release. In the new IRIS process (May 2009), introduced by the EPA Administrator, all written comments on IRIS assessments submitted by other federal agencies and White House Offices will be made publicly available. Accordingly, interagency comments and the interagency science consultation draft of the IRIS Toxicological Review of Biphenyl and the charge to external peer reviewers are posted on this site. EPA is undertaking a new health assessment for biphenyl for the Integrated Risk Information System (IRIS). The outcome of this project will be a Toxicological Review and IRIS and IRIS Summary of biohenyl that will be entered on the IRIS database. IRIS is an EPA database containing Agency scientific positions on potential adverse human health effects that may result from chronic (or lifetime) exposure to chemicals in the environment. IRIS contains chemical-specific summaries of qualitative and quantitative health information to evaluate potential public health risks associated with exposure assessment information to evaluate potential public health risks associated with environmental contaminants. The IRIS database is relied on for the development of risk ass

IRIS TOXICOLOGICAL REVIEW AND SUMMARY ...

EPA Pesticide Factsheets

EPA's assessment of the noncancer health effects and carcinogenic potential of 1,2,3-trichloropropane (TCP) was added to the IRIS database in 1990. The IRIS program is updating the IRIS assessment for TCP. This update will incorporate health effects information published since the last assessment was prepared as well as new risk assessment methods. The IRIS assessment for TCP will consist of a Toxicological Review and IRIS Summary. The Toxicological Review is a critical review of the physicochemical and toxicokinetic properties of the chemical and its toxicity in humans and experimental systems. The assessment will present reference values for noncancer effects of TCP (RfD and RfC) and a cancer assessment. The Toxicological Review and IRIS Summary will be subject to internal peer consultation, Agency review, and external scientific peer review. The final products will constitute the Agency's opinion on the toxicity of TCP. EPA is undertaking an Integrated Risk Information System (IRIS) health assessment for 1,2,3-trichloropropane. IRIS is an EPA database containing the Agency's consensus scientific positions on potential adverse human effects that may result from chronic (or lifetime) exposure to chemicals in the environment. IRIS contains chemical-specific summaries of qualitative and quantitative health information in support of two steps of the risk assessment process, i.e., hazard identification and dose-response evaluation. IRIS assessments are used in

Matrix metalloproteinases and tissue damage in HIV-tuberculosis immune reconstitution inflammatory syndrome

PubMed Central

Tadokera, Rebecca; Meintjes, Graeme A; Wilkinson, Katalin A; Skolimowska, Keira H; Walker, Naomi; Friedland, Jon S; Maartens, Gary; Elkington, Paul T G; Wilkinson, Robert J

2014-01-01

The HIV-TB-associated immune reconstitution inflammatory syndrome (TB-IRIS) can complicate combined treatments for HIV-1 and TB. Little is known about tissue damage in TB-IRIS. Matrix metalloproteinases (MMPs) degrade components of the extracellular matrix and consequently may play a role in such immunopathology. Here we investigated the involvement of MMPs in TB-IRIS. We determined MMP transcript abundance and secreted protein in Mycobacterium tuberculosis stimulated PBMCs from 22 TB-IRIS patients and 22 non-IRIS controls. We also measured MMP protein levels in corresponding serum and the effect of prednisone — which reduces the duration of symptoms in IRIS patients — or placebo treatment on MMP transcript and circulating MMP protein levels. PBMCs from TB-IRIS had increased MMP-1,-3,-7, and-10 transcript levels when compared with those of controls at either 6 or 24 h. Similarly, MMP-1,-3,-7, and-10 protein secretion in stimulated cultures was higher in TB-IRIS than in controls. Serum MMP-7 concentration was elevated in TB-IRIS and 2 weeks of corticosteroid therapy decreased this level, although not significantly. TB-IRIS is associated with a distinct pattern of MMP gene and protein activation. Modulation of dysregulated MMP activity may represent a novel therapeutic approach to alleviate TB-IRIS in HIV-TB patients undergoing treatment. PMID:24136296

[Moxiflaxin and iris transillumination].

PubMed

Broens, A; Collignon, N

2016-07-01

Bilateral Acute Iris Transillumination (BAIT) is a new clinical entity characterized by acute onset of pigment dispersion in the anterior chamber and angle, depigmentation of the iris stroma and permanent iris transillumination, masquerading as uveitis. An association with oral moxifloxacin is reported in some articles. We describe one case of bilateral acute iris transillumination, following the use of systemic moxifloxacin.

Design method of ARM based embedded iris recognition system

NASA Astrophysics Data System (ADS)

Wang, Yuanbo; He, Yuqing; Hou, Yushi; Liu, Ting

2008-03-01

With the advantages of non-invasiveness, uniqueness, stability and low false recognition rate, iris recognition has been successfully applied in many fields. Up to now, most of the iris recognition systems are based on PC. However, a PC is not portable and it needs more power. In this paper, we proposed an embedded iris recognition system based on ARM. Considering the requirements of iris image acquisition and recognition algorithm, we analyzed the design method of the iris image acquisition module, designed the ARM processing module and its peripherals, studied the Linux platform and the recognition algorithm based on this platform, finally actualized the design method of ARM-based iris imaging and recognition system. Experimental results show that the ARM platform we used is fast enough to run the iris recognition algorithm, and the data stream can flow smoothly between the camera and the ARM chip based on the embedded Linux system. It's an effective method of using ARM to actualize portable embedded iris recognition system.

Large scale tracking algorithms

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

Hansen, Ross L.; Love, Joshua Alan; Melgaard, David Kennett

2015-01-01

Low signal-to-noise data processing algorithms for improved detection, tracking, discrimination and situational threat assessment are a key research challenge. As sensor technologies progress, the number of pixels will increase signi cantly. This will result in increased resolution, which could improve object discrimination, but unfortunately, will also result in a significant increase in the number of potential targets to track. Many tracking techniques, like multi-hypothesis trackers, suffer from a combinatorial explosion as the number of potential targets increase. As the resolution increases, the phenomenology applied towards detection algorithms also changes. For low resolution sensors, "blob" tracking is the norm. For highermore » resolution data, additional information may be employed in the detection and classfication steps. The most challenging scenarios are those where the targets cannot be fully resolved, yet must be tracked and distinguished for neighboring closely spaced objects. Tracking vehicles in an urban environment is an example of such a challenging scenario. This report evaluates several potential tracking algorithms for large-scale tracking in an urban environment.« less

Human iris three-dimensional imaging at micron resolution by a micro-plenoptic camera

PubMed Central

Chen, Hao; Woodward, Maria A.; Burke, David T.; Jeganathan, V. Swetha E.; Demirci, Hakan; Sick, Volker

2017-01-01

A micro-plenoptic system was designed to capture the three-dimensional (3D) topography of the anterior iris surface by simple single-shot imaging. Within a depth-of-field of 2.4 mm, depth resolution of 10 µm can be achieved with accuracy (systematic errors) and precision (random errors) below 20%. We demonstrated the application of our micro-plenoptic imaging system on two healthy irides, an iris with naevi, and an iris with melanoma. The ridges and folds, with height differences of 10~80 µm, on the healthy irides can be effectively captured. The front surface on the iris naevi was flat, and the iris melanoma was 50 ± 10 µm higher than the surrounding iris. The micro-plenoptic imaging system has great potential to be utilized for iris disease diagnosis and continuing, simple monitoring. PMID:29082081

Human iris three-dimensional imaging at micron resolution by a micro-plenoptic camera.

PubMed

Chen, Hao; Woodward, Maria A; Burke, David T; Jeganathan, V Swetha E; Demirci, Hakan; Sick, Volker

2017-10-01

A micro-plenoptic system was designed to capture the three-dimensional (3D) topography of the anterior iris surface by simple single-shot imaging. Within a depth-of-field of 2.4 mm, depth resolution of 10 µm can be achieved with accuracy (systematic errors) and precision (random errors) below 20%. We demonstrated the application of our micro-plenoptic imaging system on two healthy irides, an iris with naevi, and an iris with melanoma. The ridges and folds, with height differences of 10~80 µm, on the healthy irides can be effectively captured. The front surface on the iris naevi was flat, and the iris melanoma was 50 ± 10 µm higher than the surrounding iris. The micro-plenoptic imaging system has great potential to be utilized for iris disease diagnosis and continuing, simple monitoring.

Toward noncooperative iris recognition: a classification approach using multiple signatures.

PubMed

Proença, Hugo; Alexandre, Luís A

2007-04-01

This paper focuses on noncooperative iris recognition, i.e., the capture of iris images at large distances, under less controlled lighting conditions, and without active participation of the subjects. This increases the probability of capturing very heterogeneous images (regarding focus, contrast, or brightness) and with several noise factors (iris obstructions and reflections). Current iris recognition systems are unable to deal with noisy data and substantially increase their error rates, especially the false rejections, in these conditions. We propose an iris classification method that divides the segmented and normalized iris image into six regions, makes an independent feature extraction and comparison for each region, and combines each of the dissimilarity values through a classification rule. Experiments show a substantial decrease, higher than 40 percent, of the false rejection rates in the recognition of noisy iris images.

Validation of a published case definition for tuberculosis-associated immune reconstitution inflammatory syndrome.

PubMed

Haddow, Lewis J; Moosa, Mahomed-Yunus S; Easterbrook, Philippa J

2010-01-02

To evaluate the International Network for the Study of HIV-associated IRIS (INSHI) case definitions for tuberculosis (TB)-associated immune reconstitution inflammatory syndrome (IRIS) in a South African cohort. Prospective cohort of 498 adult HIV-infected patients initiating antiretroviral therapy. Patients were followed up for 24 weeks and all clinical events were recorded. Events with TB-IRIS as possible cause were assessed by consensus expert opinion and INSHI case definition. Positive, negative, and chance-corrected agreement (kappa) were calculated, and reasons for disagreement were assessed. One hundred and two (20%) patients were receiving TB therapy at antiretroviral therapy initiation. Three hundred and thirty-three events were evaluated (74 potential paradoxical IRIS, 259 potential unmasking IRIS). Based on expert opinion, there were 18 cases of paradoxical IRIS associated with TB and/or other opportunistic disease. The INSHI criteria for TB-IRIS agreed in 13 paradoxical cases, giving positive agreement of 72.2%, negative agreement in 52/56 non-TB-IRIS events (92.9%), and kappa of 0.66. There were 19 unmasking TB-IRIS cases based on expert opinion, of which 12 were considered IRIS using the INSHI definition (positive agreement 63.2%). There was agreement in all 240 non-TB-IRIS events (negative agreement 100%) and kappa was 0.76. There was good agreement between the INSHI case definition for both paradoxical and unmasking TB-IRIS and consensus expert opinion. These results support the use of this definition in clinical and research practice, with minor caveats in its application.

Engineering a Light-Attenuating Artificial Iris

PubMed Central

Shareef, Farah J.; Sun, Shan; Kotecha, Mrignayani; Kassem, Iris; Azar, Dimitri; Cho, Michael

2016-01-01

Purpose Discomfort from light exposure leads to photophobia, glare, and poor vision in patients with congenital or trauma-induced iris damage. Commercial artificial iris lenses are static in nature to provide aesthetics without restoring the natural iris's dynamic response to light. A new photo-responsive artificial iris was therefore developed using a photochromic material with self-adaptive light transmission properties and encased in a transparent biocompatible polymer matrix. Methods The implantable artificial iris was designed and engineered using Photopia, a class of photo-responsive materials (termed naphthopyrans) embedded in polyethylene. Photopia was reshaped into annular disks that were spin-coated with polydimethylsiloxane (PDMS) to form our artificial iris lens of controlled thickness. Results Activated by UV and blue light in approximately 5 seconds with complete reversal in less than 1 minute, the artificial iris demonstrates graded attenuation of up to 40% of visible and 60% of UV light. There optical characteristics are suitable to reversibly regulate the incident light intensity. In vitro cell culture experiments showed up to 60% cell death within 10 days of exposure to Photopia, but no significant cell death observed when cultured with the artificial iris with protective encapsulation. Nuclear magnetic resonance spectroscopy confirmed these results as there was no apparent leakage of potentially toxic photochromic material from the ophthalmic device. Conclusions Our artificial iris lens mimics the functionality of the natural iris by attenuating light intensity entering the eye with its rapid reversible change in opacity and thus potentially providing an improved treatment option for patients with iris damage. PMID:27116547

Engineering a Light-Attenuating Artificial Iris.

PubMed

Shareef, Farah J; Sun, Shan; Kotecha, Mrignayani; Kassem, Iris; Azar, Dimitri; Cho, Michael

2016-04-01

Discomfort from light exposure leads to photophobia, glare, and poor vision in patients with congenital or trauma-induced iris damage. Commercial artificial iris lenses are static in nature to provide aesthetics without restoring the natural iris's dynamic response to light. A new photo-responsive artificial iris was therefore developed using a photochromic material with self-adaptive light transmission properties and encased in a transparent biocompatible polymer matrix. The implantable artificial iris was designed and engineered using Photopia, a class of photo-responsive materials (termed naphthopyrans) embedded in polyethylene. Photopia was reshaped into annular disks that were spin-coated with polydimethylsiloxane (PDMS) to form our artificial iris lens of controlled thickness. Activated by UV and blue light in approximately 5 seconds with complete reversal in less than 1 minute, the artificial iris demonstrates graded attenuation of up to 40% of visible and 60% of UV light. There optical characteristics are suitable to reversibly regulate the incident light intensity. In vitro cell culture experiments showed up to 60% cell death within 10 days of exposure to Photopia, but no significant cell death observed when cultured with the artificial iris with protective encapsulation. Nuclear magnetic resonance spectroscopy confirmed these results as there was no apparent leakage of potentially toxic photochromic material from the ophthalmic device. Our artificial iris lens mimics the functionality of the natural iris by attenuating light intensity entering the eye with its rapid reversible change in opacity and thus potentially providing an improved treatment option for patients with iris damage.

SU-E-T-453: A Novel Daily QA System for Robotic Image Guided Radiosurgery with Variable Aperture Collimator

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

Wang, L; Nelson, B

Purpose: A novel end-to-end system using a CCD camera and a scintillator based phantom that is capable of measuring the beam-by-beam delivery accuracy of Robotic Radiosurgery has been developed and reported in our previous work. This work investigates its application to end-to-end type daily QA for Robotic Radiosurgery (Cyberknife) with Variable Aperture Collimator (Iris). Methods: The phantom was first scanned with a CT scanner at 0.625 slice thickness and exported to the Cyberknife Muliplan (v4.6) treatment planning system. An isocentric treatment plan was created consisting of ten beams of 25 Monitor Units each using Iris apertures of 7.5, 10, 15,more » 20, and 25 mm. The plan was delivered six times in two days on the Cyberknife G4 system with fiducial tracking on the four metal fiducials embedded in phantom with re-positioning between the measurements. The beam vectors (X, Y, Z) are measured and compared with the plan from the machine delivery file (XML file). The Iris apertures (FWHM) were measured from the beam flux map and compared with the commissioning data. Results: The average beam positioning accuracies of the six deliveries are 0.71 ± 0.40 mm, 0.72 ± 0.44 mm, 0.74 ± 0.42 mm, 0.70 ± 0.40 mm, 0.79 ± 0.44 mm and 0.69 ± 0.41 mm respectively. Radiation beam width (FWHM) variations are within ±0.05 mm, and they agree with the commissioning data within 0.22 mm. The delivery time for the plan is about 7 minutes and the results are given instantly. Conclusion: The experimental results agree with stated sub-millimeter delivery accuracy of Cyberknife system. Beam FWHM variations comply with the 0.2 mm accuracy of the Iris collimator at SAD. The XRV-100 system has proven to be a powerful tool in performing end-to-end type tests for Robotic Image Guided Radiosurgery Daily QA.« less

Multi-instrument study of chromospheric jets

NASA Astrophysics Data System (ADS)

Vanninathan, Kamalam; Madjarska, Maria; Doyle, Gerry

2012-03-01

The contribution to coronal heating by jets of various kinds like spicules, mottles, surges etc. originating in the solar chromosphere is an issue which is being currently largely explored. We analyse multi-instrument data taken in the plage area of active regions during dedicated observing runs with ROSA, IBIS at Sac Peak, USA, SOT, EIS/XRT/Hinode and AIA/SDO. The high-resolution and high-cadence data allow us to track chromospheric jets through the solar atmosphere and thus helps us to understand the dynamics and plasma properties of these features. The study is a forward step towards the exploration of the forthcoming state-of-art IRIS observations.

Infrared Imagery of Shuttle (IRIS). Task 2. [indium antimonide sensors

NASA Technical Reports Server (NTRS)

Chocol, C. J.

1978-01-01

An opto-electronic breadboard of 10 channels of the IR temperature measuring system was produced as well as a scaled up portion of the tracking system reticle in order to verify Task 1 assumptions. The breadboards and the tests performed on them are described and both raw and reduced data are presented. Tests show that the electronics portion of the imaging system will provide a dc to 10,000 Hz bandwidth that is flat and contributes no more than 0.4% of full-scale uncertainty to the measurement. Conventional packaging is adequate for the transresistance amplifier design. Measurement errors expected from all sources tested are discussed.

Video-based noncooperative iris image segmentation.

PubMed

Du, Yingzi; Arslanturk, Emrah; Zhou, Zhi; Belcher, Craig

2011-02-01

In this paper, we propose a video-based noncooperative iris image segmentation scheme that incorporates a quality filter to quickly eliminate images without an eye, employs a coarse-to-fine segmentation scheme to improve the overall efficiency, uses a direct least squares fitting of ellipses method to model the deformed pupil and limbic boundaries, and develops a window gradient-based method to remove noise in the iris region. A remote iris acquisition system is set up to collect noncooperative iris video images. An objective method is used to quantitatively evaluate the accuracy of the segmentation results. The experimental results demonstrate the effectiveness of this method. The proposed method would make noncooperative iris recognition or iris surveillance possible.

Iris Recognition: The Consequences of Image Compression

NASA Astrophysics Data System (ADS)

Ives, Robert W.; Bishop, Daniel A.; Du, Yingzi; Belcher, Craig

2010-12-01

Iris recognition for human identification is one of the most accurate biometrics, and its employment is expanding globally. The use of portable iris systems, particularly in law enforcement applications, is growing. In many of these applications, the portable device may be required to transmit an iris image or template over a narrow-bandwidth communication channel. Typically, a full resolution image (e.g., VGA) is desired to ensure sufficient pixels across the iris to be confident of accurate recognition results. To minimize the time to transmit a large amount of data over a narrow-bandwidth communication channel, image compression can be used to reduce the file size of the iris image. In other applications, such as the Registered Traveler program, an entire iris image is stored on a smart card, but only 4 kB is allowed for the iris image. For this type of application, image compression is also the solution. This paper investigates the effects of image compression on recognition system performance using a commercial version of the Daugman iris2pi algorithm along with JPEG-2000 compression, and links these to image quality. Using the ICE 2005 iris database, we find that even in the face of significant compression, recognition performance is minimally affected.

A novel in vivo model of puncture-induced iris neovascularization.

PubMed

Beaujean, Ophélie; Locri, Filippo; Aronsson, Monica; Kvanta, Anders; André, Helder

2017-01-01

To assess iris neovascularization by uveal puncture of the mouse eye and determine the role of angiogenic factors during iris neovascularization. Uveal punctures were performed on BalbC mouse eyes to induce iris angiogenesis. VEGF-blockage was used as an anti-angiogenic treatment, while normoxia- and hypoxia-conditioned media from retinal pigment epithelium (RPE) cells was used as an angiogenic-inducer in this model. Iris vasculature was determined in vivo by noninvasive methods. Iris blood vessels were stained for platelet endothelial cell adhesion molecule-1 and vascular sprouts were counted as markers of angiogenesis. Expression of angiogenic and inflammatory factors in the puncture-induced model were determined by qPCR and western blot. Punctures led to increased neovascularization and sprouting of the iris. qPCR and protein analysis showed an increase of angiogenic factors, particularly in the plasminogen-activating receptor and inflammatory systems. VEGF-blockage partly reduced iris neovascularization, and treatment with hypoxia-conditioned RPE medium led to a statistically significant increase in iris neovascularization. This study presents the first evidence of a puncture-induced iris angiogenesis model in the mouse. In a broader context, this novel in vivo model of neovascularization has the potential for noninvasive evaluation of angiogenesis modulating substances.

Iris recognition in the presence of ocular disease

PubMed Central

Aslam, Tariq Mehmood; Tan, Shi Zhuan; Dhillon, Baljean

2009-01-01

Iris recognition systems are among the most accurate of all biometric technologies with immense potential for use in worldwide security applications. This study examined the effect of eye pathology on iris recognition and in particular whether eye disease could cause iris recognition systems to fail. The experiment involved a prospective cohort of 54 patients with anterior segment eye disease who were seen at the acute referral unit of the Princess Alexandra Eye Pavilion in Edinburgh. Iris camera images were obtained from patients before treatment was commenced and again at follow-up appointments after treatment had been given. The principal outcome measure was that of mathematical difference in the iris recognition templates obtained from patients' eyes before and after treatment of the eye disease. Results showed that the performance of iris recognition was remarkably resilient to most ophthalmic disease states, including corneal oedema, iridotomies (laser puncture of iris) and conjunctivitis. Problems were, however, encountered in some patients with acute inflammation of the iris (iritis/anterior uveitis). The effects of a subject developing anterior uveitis may cause current recognition systems to fail. Those developing and deploying iris recognition should be aware of the potential problems that this could cause to this key biometric technology. PMID:19324690

Iris recognition in the presence of ocular disease.

PubMed

Aslam, Tariq Mehmood; Tan, Shi Zhuan; Dhillon, Baljean

2009-05-06

Iris recognition systems are among the most accurate of all biometric technologies with immense potential for use in worldwide security applications. This study examined the effect of eye pathology on iris recognition and in particular whether eye disease could cause iris recognition systems to fail. The experiment involved a prospective cohort of 54 patients with anterior segment eye disease who were seen at the acute referral unit of the Princess Alexandra Eye Pavilion in Edinburgh. Iris camera images were obtained from patients before treatment was commenced and again at follow-up appointments after treatment had been given. The principal outcome measure was that of mathematical difference in the iris recognition templates obtained from patients' eyes before and after treatment of the eye disease. Results showed that the performance of iris recognition was remarkably resilient to most ophthalmic disease states, including corneal oedema, iridotomies (laser puncture of iris) and conjunctivitis. Problems were, however, encountered in some patients with acute inflammation of the iris (iritis/anterior uveitis). The effects of a subject developing anterior uveitis may cause current recognition systems to fail. Those developing and deploying iris recognition should be aware of the potential problems that this could cause to this key biometric technology.

Tuberculosis immune reconstitution inflammatory syndrome in A5221 STRIDE: timing, severity, and implications for HIV-TB programs.

PubMed

Luetkemeyer, Anne F; Kendall, Michelle A; Nyirenda, Mulinda; Wu, Xingye; Ive, Prudence; Benson, Constance A; Andersen, Janet W; Swindells, Susan; Sanne, Ian M; Havlir, Diane V; Kumwenda, Johnstone

2014-04-01

Earlier initiation of antiretroviral therapy (ART) in HIV-tuberculosis (TB) is associated with increased immune reconstitution inflammatory syndrome (IRIS). The severity, frequency, and complications of TB IRIS were evaluated in A5221, a randomized trial of earlier ART (within 2 weeks after TB treatment initiation) vs. later ART (8-12 weeks after TB treatment) in HIV-infected patients starting TB treatment. In 806 participants, TB IRIS was defined using published clinical criteria. Cases were classified as severe (hospitalization/death), moderate (corticosteroid use/invasive procedure), or mild (no hospitalization/procedures/steroids). Fisher exact, Wilcoxon, and log-rank tests were used for comparisons. TB IRIS occurred in 61 (7.6%) patients: 10.4% in earlier vs. 4.7% in later ART, 11.5% with CD4 <50 vs. 5.4% with CD4 ≥50 cells per cubic millimeter. The CD4/ART arm interaction was significant, P = 0.014, with 44.3% of TB IRIS occurring with CD4 <50 and earlier ART. TB IRIS occurred sooner with earlier vs. later ART initiation, at a median of 29 vs. 82 days after TB treatment initiation (P < 0.001). IRIS manifestations included lymphadenopathy (59.0%), constitutional symptoms (54.1%), and radiographic changes (41.0%); central nervous system TB IRIS was uncommon (6.6%). TB IRIS was mild in 27.9%, moderate in 41.0%, and severe in 31.1%. No TB IRIS-associated deaths occurred. IRIS management required ≥1 invasive procedures in 34.4%, hospitalization in 31.1%, and corticosteroids in 54.1%. TB IRIS was more frequent with earlier ART initiation and CD4 <50 cells per cubic millimeter. As ART is implemented earlier in HIV-TB coinfection, programs will require the diagnostic capabilities, clinical resources, and training necessary to manage TB IRIS.

Quantitative study of the microvasculature and its endothelial cells in the porcine iris.

PubMed

Yang, Hongfang; Yu, Paula K; Cringle, Stephen J; Sun, Xinghuai; Yu, Dao-Yi

2015-03-01

The roles of the iris microvasculature have been increasingly recognised in the pathogenesis of glaucoma and cataract; however limited information exists regarding the iris microvasculature and its endothelium. This study quantitatively assessed the iris microvascular network and its endothelium using intra-luminal micro-perfusion, fixation, and staining of the porcine iris. The temporal long posterior ciliary artery of 11 isolated porcine eyes was cannulated, perfusion-fixed and labelled using silver nitrate. The iris microvasculature was studied for its distribution, orders and endothelial morphometrics. The density of three layers of microvasculature was measured. Endothelial cell length and width were measured for each vessel order. The iris has an unusual vascular distribution which consisted of abundant large vessels in the middle of the iris stroma, branching over a relatively short distance to the microvasculature located in the superficial and deep stroma as well as the pupil edge. The average vascular density of the middle, superficial, and deep layers were 38.9 ± 1.93%, 10.9 ± 1.61% and 8.0 ± 0.79% respectively. Multiple orders of iris vessels (capillary, 6 orders of arteries, and 4 orders of veins) with relatively large capillary and input arteries (319.5 ± 25.6 μm) were found. Significant heterogeneity of vascular diameter and shape of the endothelia was revealed in different orders of the iris vasculature. Detailed information of topography and endothelium of the iris microvasculature combined with unique structural features of the iris may help us to further understand the physiological and pathogenic roles of the iris in relevant ocular diseases. Copyright © 2015 Elsevier Ltd. All rights reserved.

Lower Pre-Treatment T Cell Activation in Early- and Late-Onset Tuberculosis-Associated Immune Reconstitution Inflammatory Syndrome

PubMed Central

Goovaerts, Odin; Jennes, Wim; Massinga-Loembé, Marguerite; Ondoa, Pascale; Ceulemans, Ann; Vereecken, Chris; Worodria, William; Mayanja-Kizza, Harriet; Colebunders, Robert; Kestens, Luc

2015-01-01

Background Tuberculosis-associated immune reconstitution inflammatory syndrome (TB-IRIS) is an inflammatory complication in HIV-TB co-infected patients receiving antiretroviral therapy (ART). The role of disturbed T cell reconstitution in TB-IRIS is not well understood. We investigated T cell activation and maturation profiles in patients who developed TB-IRIS at different intervals during ART. Methods Twenty-two HIV-TB patients who developed early-onset TB-IRIS and 10 who developed late-onset TB-IRIS were matched for age, sex and CD4 count to equal numbers of HIV-TB patients who did not develop TB-IRIS. Flow cytometry analysis was performed on fresh blood, drawn before and after ART initiation and during TB-IRIS events. T cell activation and maturation was measured on CD4+ and CD8+ T cells using CD45RO, CD38, HLA-DR, CCR7 and CD27 antibodies. Results CD8+ T cell activation before ART was decreased in both early-onset (77% vs. 82%, p = 0.014) and late-onset (71% vs. 83%, p = 0.012) TB-IRIS patients compared to non-IRIS controls. After ART initiation, the observed differences in T cell activation disappeared. During late-onset, but not early-onset TB-IRIS, we observed a skewing from memory to terminal effector CD4+ and CD8+ T cell populations (p≤0.028). Conclusion Our data provide evidence of reduced CD8+ T cell activation before ART as a common predisposing factor of early- and late-onset TB-IRIS. The occurrence of TB-IRIS itself was not marked by an over-activated CD8+ T cell compartment. Late- but not early-onset TB-IRIS was characterized by a more terminally differentiated T cell phenotype. PMID:26208109

A VidEo-Based Intelligent Recognition and Decision System for the Phacoemulsification Cataract Surgery.

PubMed

Tian, Shu; Yin, Xu-Cheng; Wang, Zhi-Bin; Zhou, Fang; Hao, Hong-Wei

2015-01-01

The phacoemulsification surgery is one of the most advanced surgeries to treat cataract. However, the conventional surgeries are always with low automatic level of operation and over reliance on the ability of surgeons. Alternatively, one imaginative scene is to use video processing and pattern recognition technologies to automatically detect the cataract grade and intelligently control the release of the ultrasonic energy while operating. Unlike cataract grading in the diagnosis system with static images, complicated background, unexpected noise, and varied information are always introduced in dynamic videos of the surgery. Here we develop a Video-Based Intelligent Recognitionand Decision (VeBIRD) system, which breaks new ground by providing a generic framework for automatically tracking the operation process and classifying the cataract grade in microscope videos of the phacoemulsification cataract surgery. VeBIRD comprises a robust eye (iris) detector with randomized Hough transform to precisely locate the eye in the noise background, an effective probe tracker with Tracking-Learning-Detection to thereafter track the operation probe in the dynamic process, and an intelligent decider with discriminative learning to finally recognize the cataract grade in the complicated video. Experiments with a variety of real microscope videos of phacoemulsification verify VeBIRD's effectiveness.

A VidEo-Based Intelligent Recognition and Decision System for the Phacoemulsification Cataract Surgery

PubMed Central

Yin, Xu-Cheng; Wang, Zhi-Bin; Zhou, Fang; Hao, Hong-Wei

2015-01-01

The phacoemulsification surgery is one of the most advanced surgeries to treat cataract. However, the conventional surgeries are always with low automatic level of operation and over reliance on the ability of surgeons. Alternatively, one imaginative scene is to use video processing and pattern recognition technologies to automatically detect the cataract grade and intelligently control the release of the ultrasonic energy while operating. Unlike cataract grading in the diagnosis system with static images, complicated background, unexpected noise, and varied information are always introduced in dynamic videos of the surgery. Here we develop a Video-Based Intelligent Recognitionand Decision (VeBIRD) system, which breaks new ground by providing a generic framework for automatically tracking the operation process and classifying the cataract grade in microscope videos of the phacoemulsification cataract surgery. VeBIRD comprises a robust eye (iris) detector with randomized Hough transform to precisely locate the eye in the noise background, an effective probe tracker with Tracking-Learning-Detection to thereafter track the operation probe in the dynamic process, and an intelligent decider with discriminative learning to finally recognize the cataract grade in the complicated video. Experiments with a variety of real microscope videos of phacoemulsification verify VeBIRD's effectiveness. PMID:26693249

Chromospheric impact of an exploding solar granule

NASA Astrophysics Data System (ADS)

Fischer, C. E.; Bello González, N.; Rezaei, R.

2017-06-01

Context. Observations of multi-wavelength and therefore height-dependent information following events throughout the solar atmosphere and unambiguously assigning a relation between these rapidly evolving layers are rare and difficult to obtain. Yet, they are crucial for our understanding of the physical processes that couple the different regimes in the solar atmosphere. Aims: We characterize the exploding granule event with simultaneous observations of Hinode spectroplarimetric data in the solar photosphere and Hinode broadband Ca II H images combined with Interface Region Imaging Spectrograph (IRIS) slit spectra. We follow the evolution of an exploding granule and its connectivity throughout the atmosphere and analyze the dynamics of a magnetic element that has been affected by the abnormal granule. Methods: In addition to magnetic flux maps we use a local correlation tracking method to infer the horizontal velocity flows in the photosphere and apply a wavelet analysis on several IRIS chromospheric emission features such as Mg II k2v and Mg II k3 to detect oscillatory phenomena indicating wave propagation. Results: During the vigorous expansion of the abnormal granule we detect radially outward horizontal flows, causing, together with the horizontal flows from the surrounding granules, the magnetic elements in the bordering intergranular lanes to be squeezed and elongated. In reaction to the squeezing, we detect a chromospheric intensity and velocity oscillation pulse which we identify as an upward traveling hot shock front propagating clearly through the IRIS spectral line diagnostics of Mg II h&k. Conclusions: Exploding granules can trigger upward-propagating shock fronts that dissipate in the chromosphere. Movies associated to Figs. A.1 and A.2 are available in electronic form at http://www.aanda.org

Seasonal and Inter-Annual Patterns of Chlorophyll and Phytoplankton Community Structure in Monterey Bay, CA Derived from AVIRIS Data During the 2013-2015 HyspIRI Airborne Campaign

NASA Astrophysics Data System (ADS)

Palacios, S. L.; Thompson, D. R.; Kudela, R. M.; Negrey, K.; Guild, L. S.; Gao, B. C.; Green, R. O.; Torres-Perez, J. L.

2016-02-01

There is a need in the ocean color community to discriminate among phytoplankton groups within the bulk chlorophyll pool to understand ocean biodiversity, track energy flow through ecosystems, and identify and monitor for harmful algal blooms. Imaging spectrometer measurements enable the use of sophisticated spectroscopic algorithms for applications such as differentiating among coral species and discriminating phytoplankton taxa. These advanced algorithms rely on the fine scale, subtle spectral shape of the atmospherically corrected remote sensing reflectance (Rrs) spectrum of the ocean surface. Consequently, these algorithms are sensitive to inaccuracies in the retrieved Rrs spectrum that may be related to the presence of nearby clouds, inadequate sensor calibration, low sensor signal-to-noise ratio, glint correction, and atmospheric correction. For the HyspIRI Airborne Campaign, flight planning considered optimal weather conditions to avoid flights with significant cloud/fog cover. Although best suited for terrestrial targets, the Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) has enough signal for some coastal chlorophyll algorithms and meets sufficient calibration requirements for most channels. The coastal marine environment has special atmospheric correction needs due to error introduced by aerosols and terrestrially sourced atmospheric dust and riverine sediment plumes. For this HyspIRI campaign, careful attention has been given to the correction of AVIRIS imagery of the Monterey Bay to optimize ocean Rrs retrievals to estimate chlorophyll (OC3) and phytoplankton functional type (PHYDOTax) data products. This new correction method has been applied to several image collection dates during two oceanographic seasons in 2013 and 2014. These two periods are dominated by either diatom blooms or red tides. Results to be presented include chlorophyll and phytoplankton community structure and in-water validation data for these dates during the two seasons.

Activation of Ice Recrystallization Inhibition Activity of Poly(vinyl alcohol) using a Supramolecular Trigger†

PubMed Central

Phillips, Daniel J.; Congdon, Thomas R.; Gibson, Matthew I.

2016-01-01

Antifreeze (glyco)proteins (AF(G)Ps) have potent ice recrystallisation inhibition (IRI) activity – a desirable phenomenon in applications such as cryopreservation, frozen food and more. In Nature AF(G)P activity is regulated by protein expression levels in response to an environmental stimulus; temperature. However, this level of regulation is not possible in synthetic systems. Here, a synthetic macromolecular mimic is introduced, using supramolecular assembly to regulate activity. Catechol-terminated poly(vinyl alcohol) was synthesised by RAFT polymerization. Upon addition of Fe3+, larger supramolecular star polymers form by assembly with two or three catechols. This increase in molecular weight effectively ‘switches on’ the IRI activity and is the first example of external control over the function of AFP mimetics. This provides a simple but elegant solution to the challenge of external control of AFP-mimetic function. PMID:28003855

The iris – a window into the genetics of common and rare eye diseases

PubMed Central

Morrison, Patrick J

2010-01-01

Visual examination, without instruments, of the eye allows inspection of the iris, sclera, cornea and, through the iris, some abnormalities of the lens and retina. Several hereditary disorders can easily be recognised by characteristic iris changes. This review discusses changes in the iris, visible lens anomalies, and changes in the cornea surrounding the iris. A genetic diagnosis can help with management of diseases. Some conditions are single gene disorders, some are chromosomal rearrangements, and some are abnormalities of fetal development. PMID:20844723

Iris Freckles a Potential Biomarker for Chronic Sun Damage.

PubMed

Schwab, Christoph; Mayer, Christoph; Zalaudek, Iris; Riedl, Regina; Richtig, Markus; Wackernagel, Werner; Hofmann-Wellenhof, Rainer; Richtig, Georg; Langmann, Gerald; Tarmann, Lisa; Wedrich, Andreas; Richtig, Erika

2017-05-01

To investigate the role of sunlight exposure in iris freckles formation. We prospectively examined volunteers attending a skin cancer screening program conducted by ophthalmologists and dermatologists. Frequency and topographical variability of iris freckles were noted and associated with behavioral and dermatologic characteristics indicating high sun exposure. Six hundred thirty-two participants (n = 360; 57% female) were examined. Mean age of all participants was 38.4 ± 18.4 years (range, 4-84 years). Of all individuals, 76.1% (n = 481) exhibited at least one iris freckle. Most freckles were observed in the inferior temporal quadrant. The presence of iris freckles was associated with higher age (participants with iris freckles: 41.8 ± 16.8 years versus participants without iris freckles: 27.6 ± 19.2 years), a high number of sunburns during lifetime (>10: 31% vs. 19%), sunlight-damaged skin (26% vs. 11%), presence of actinic lentigines (72% vs. 45%), and a high total nevus body count (>10; 78% vs. 67%). The association of iris freckles, behavioral factors, and dermatologic findings, as well as the topographical distribution, indicate that sunlight exposure may trigger the formation of iris freckles. The evaluation of iris freckles offers an easily accessible potential biomarker, which might be helpful in indicating sun damage on the skin associated with cutaneous malignancies. Furthermore, the evaluation of iris freckles could also be helpful in understanding the role of sunlight in several ophthalmologic diseases.

Morphological Alterations Within the Peripheral Fixation of the Iris Dilator Muscle in Eyes With Pigmentary Glaucoma

PubMed Central

Flügel-Koch, Cassandra M.; Tektas, Ozan Y.; Kaufman, Paul L.; Paulsen, Friedrich P.; Lütjen-Drecoll, Elke

2014-01-01

Purpose. To analyze the peripheral fixation of the iris dilator muscle in normal eyes and in eyes with pigmentary glaucoma (PG). Methods. Using 63 control eyes (age 18 months–99 years), the peripheral iris dilator was investigated by light microscopy, immunohistochemistry, and electron microscopy. Development was studied using 18 differently aged fetal eyes stained immunohistochemically against α-smooth muscle (SM) actin. The peripheral iris dilator muscle in PG was analyzed using semithin and ultrathin sections of six glutaraldehyde-fixed eyes from three donors aged 38, 62, and 74 years. Results. In normal eyes, the peripheral end of the iris dilator muscle is arranged in a sphincter-like manner. Arcade-shaped tendinous connections associated with myofibroblasts (iridial strands) anchor the iris dilator within the elastic–fibromuscular ciliary meshwork that also serves as fixation area for the elastic tendons of the inner ciliary muscle portions. The iridial strands are innervated and can adapt their length during accommodation. The PG eyes show incomplete circular bundles and iridial strands that are mainly anchored to the iris stroma and the flexible uveal parts of the trabecular meshwork. Conclusions. The normal anchorage of the peripheral iris dilator and its presumably neuronally regulated length adaptation stabilize the peripheral iris during accommodation. Insufficient fixation in PG could promote posterior bowing of the iris with rubbing against the zonular fibers and pigment liberation from the iris pigmented epithelium. PMID:24938519

The voices of Iris: Cinematic representations of the aged woman and Alzheimer's disease in Iris (2001).

PubMed

Graham, Megan E

2016-09-01

Audiences must be critical of film representations of the aged woman living with Alzheimer's disease and of dangerous reinscriptions of stereotypical equations about ageing as deterioration. This paper analyses the representation and decline of the aged woman through the different voices of Iris Murdoch in Richard Eyre's film Iris (2001). Key vocal scenes are considered: On-screen encounters between young and aged Iris, vocal representations of dementia symptoms and silencing Iris as her disease progresses. Further, Iris' recurrent unaccompanied song, "The Lark in the Clear Air," compels audiences to "see" Iris with their ears more than with their eyes, exemplifying the representational power of sound in film. This paper is an appeal for increased debate about sonic representations of aged women, ageing and Alzheimer's disease and dementia in film. The significance of audiences' critical awareness and understanding about the social implications of these representations is discussed. © The Author(s) 2014.

Iris Segmentation and Normalization Algorithm Based on Zigzag Collarette

NASA Astrophysics Data System (ADS)

Rizky Faundra, M.; Ratna Sulistyaningrum, Dwi

2017-01-01

In this paper, we proposed iris segmentation and normalization algorithm based on the zigzag collarette. First of all, iris images are processed by using Canny Edge Detection to detect pupil edge, then finding the center and the radius of the pupil with the Hough Transform Circle. Next, isolate important part in iris based zigzag collarette area. Finally, Daugman Rubber Sheet Model applied to get the fixed dimensions or normalization iris by transforming cartesian into polar format and thresholding technique to remove eyelid and eyelash. This experiment will be conducted with a grayscale eye image data taken from a database of iris-Chinese Academy of Sciences Institute of Automation (CASIA). Data iris taken is the data reliable and widely used to study the iris biometrics. The result show that specific threshold level is 0.3 have better accuracy than other, so the present algorithm can be used to segmentation and normalization zigzag collarette with accuracy is 98.88%

Iris metastasis of gastric adenocarcinoma.

PubMed

Celebi, Ali Riza Cenk; Kilavuzoglu, Ayse Ebru; Altiparmak, U Emrah; Cosar, C Banu; Ozkiris, Abdullah

2016-03-08

Iris metastasis in patients with gastric cancer is extremely rare. Herein, it is aimed to report on a patient with gastric adenocarcinoma and iris metastasis. A 65-year-old patient with the history of gastric cancer was admitted for eye pain and eye redness on his left eye. There was ciliary injection, severe +4 cells with hypopyon in the anterior chamber and a solitary, friable, yellow-white, fleshy-creamy vascularized 2 mm × 4 mm mass on the upper nasal part of the iris within the left eye. The presented patient's mass lesion in the iris fulfilled the criteria of the metastatic iris lesion's appearance. The ocular metastasis occurred during chemotherapy. Iris metastasis can masquerade as iridocyclitis with pseudohypopyon or glaucoma. In patients with a history of gastric cancer that present with an iris mass, uveitis, and high intraocular pressure, ocular metastasis of gastric cancer should be a consideration.

Comparison of GPS derived TEC with the TEC predicted by IRI 2012 model in the southern Equatorial Ionization Anomaly crest within the Eastern Africa region

NASA Astrophysics Data System (ADS)

Sulungu, Emmanuel D.; Uiso, Christian B. S.; Sibanda, Patrick

2018-04-01

We have compared the TEC obtained from the IRI-2012 model with the GPS derived TEC data recorded within southern crest of the EIA in the Eastern Africa region using the monthly means of the 5 international quiet days for equinoxes and solstices months for the period of 2012 - 2013. GPS-derived TEC data have been obtained from the Africa array and IGS network of ground based dual-frequency GPS receivers from four stations (Kigali (1.95°S, 30.09°E; Geom. Lat. 11.63°S), Malindi (2.99°S, 40.19°E; Geom. Lat. 12.42°S), Mbarara (0.60°S, 30.74°E; Geom. Lat. 10.22°S) and Nairobi (1.22°S, 36.89°E; Geom. Lat. 10.69°S)) located within the EIA crest in this region. All the three options for topside Ne of IRI-2012 model and ABT-2009 for bottomside thickness have been used to compute the IRI TEC. Also URSI coefficients were considered in this study. These results are compared with the TEC estimated from GPS measurements. Correlation Coefficients between the two sets of data, the Root-Mean Square Errors (RMSE) of the IRI-TEC from the GPS-TEC, and the percentage RMSE of the IRI-TEC from the GPS-TEC have been computed. Our general results show that IRI-2012 model with all three options overestimates the GPS-TEC for all seasons and at all stations, and IRI-2001 overestimates GPS-TEC more compared with other options. IRI-Neq and IRI-01-corr are closely matching in most of the time. The observation also shows that, GPS TEC are underestimated by TEC from IRI model during noon hours, especially during equinoctial months. Further, GPS-TEC values and IRI-TEC values using all the three topside Ne options show very good correlation (above 0.8). On the other hand, the TEC using IRI-Neq and IRI-01- corr had smaller deviations from the GPS-TEC compared to the IRI-2001.

PLATEAU IRIS--DIAGNOSIS AND TREATMENT.

PubMed

Stefan, Cornel; Iliescu, Daniela Adriana; Batras, Mehdi; Timaru, Cristina Mihaela; De Simone, Algerino

2015-01-01

The objective of our study was to review the current knowledge on the diagnosis and treatment options of plateau iris configuration and syndrome. Relevant publications on plateau iris that were published until 2014. Plateau iris syndrome is a form of primary angle closure glaucoma caused by a large or anteriorly positioned ciliary body that leads to mechanical obstruction of trabecular meshwork. This condition is most often found in younger patients. Plateau iris has been considered an abnormal anatomic variant of the iris that can be diagnosed on ultrasound biomicroscopy or optical coherence tomography of anterior segment. Patients with plateau iris syndrome can be recognized by the lack of response in angle opening after iridotomy. The treatment of choice in these cases is argon laser peripheral iridoplasty.

[Implantation of an Artificial Iris in 11 Patients].

PubMed

Kniestedt, C; Eberhard, R; Fleischhauer, J

2016-04-01

Background. Iris defects are mostly acquired after injury, or may be iatrogenic after surgical excision of iris tumours or the result of collateral trauma after anterior segment surgery. They cause severe visual disability, e.g. glare, loss of contrast sensitivity, and loss of best corrected visual acuity. The foldable Koch iris prosthesis has a customised iris design and may be used to reconstruct the anterior segment in patients with partial or complete aniridia. History and Signs. We present the surgical management and clinical course of 6 patients with traumatic iris defects, together with 3 patients with partial aniridia after cataract surgery. Cataract surgery and implantation of an artificial iris were performed in 2 female patients (3 eyes) with congenital aniridia syndrome. Therapy and Outcome. No patient exhibited complications in the postoperative course, with the exception of various intraocular pressure peaks due to secondary glaucoma, that were all corrected by medication to lower topical pressure. Conclusions. In patients with major iris defects, the artificial iris allows functionally and aesthetically satisfactory reconstruction of the anterior segment. Georg Thieme Verlag KG Stuttgart · New York.

Feature Vector Construction Method for IRIS Recognition

NASA Astrophysics Data System (ADS)

Odinokikh, G.; Fartukov, A.; Korobkin, M.; Yoo, J.

2017-05-01

One of the basic stages of iris recognition pipeline is iris feature vector construction procedure. The procedure represents the extraction of iris texture information relevant to its subsequent comparison. Thorough investigation of feature vectors obtained from iris showed that not all the vector elements are equally relevant. There are two characteristics which determine the vector element utility: fragility and discriminability. Conventional iris feature extraction methods consider the concept of fragility as the feature vector instability without respect to the nature of such instability appearance. This work separates sources of the instability into natural and encodinginduced which helps deeply investigate each source of instability independently. According to the separation concept, a novel approach of iris feature vector construction is proposed. The approach consists of two steps: iris feature extraction using Gabor filtering with optimal parameters and quantization with separated preliminary optimized fragility thresholds. The proposed method has been tested on two different datasets of iris images captured under changing environmental conditions. The testing results show that the proposed method surpasses all the methods considered as a prior art by recognition accuracy on both datasets.

IRiS: construction of ARG networks at genomic scales.

PubMed

Javed, Asif; Pybus, Marc; Melé, Marta; Utro, Filippo; Bertranpetit, Jaume; Calafell, Francesc; Parida, Laxmi

2011-09-01

Given a set of extant haplotypes IRiS first detects high confidence recombination events in their shared genealogy. Next using the local sequence topology defined by each detected event, it integrates these recombinations into an ancestral recombination graph. While the current system has been calibrated for human population data, it is easily extendible to other species as well. IRiS (Identification of Recombinations in Sequences) binary files are available for non-commercial use in both Linux and Microsoft Windows, 32 and 64 bit environments from https://researcher.ibm.com/researcher/view_project.php?id = 2303 parida@us.ibm.com.

A new approach for cancelable iris recognition

NASA Astrophysics Data System (ADS)

Yang, Kai; Sui, Yan; Zhou, Zhi; Du, Yingzi; Zou, Xukai

2010-04-01

The iris is a stable and reliable biometric for positive human identification. However, the traditional iris recognition scheme raises several privacy concerns. One's iris pattern is permanently bound with him and cannot be changed. Hence, once it is stolen, this biometric is lost forever as well as all the applications where this biometric is used. Thus, new methods are desirable to secure the original pattern and ensure its revocability and alternatives when compromised. In this paper, we propose a novel scheme which incorporates iris features, non-invertible transformation and data encryption to achieve "cancelability" and at the same time increases iris recognition accuracy.

Iris indexing based on local intensity order pattern

NASA Astrophysics Data System (ADS)

Emerich, Simina; Malutan, Raul; Crisan, Septimiu; Lefkovits, Laszlo

2017-03-01

In recent years, iris biometric systems have increased in popularity and have been proven that are capable of handling large-scale databases. The main advantage of these systems is accuracy and reliability. A proper iris patterns classification is expected to reduce the matching time in huge databases. This paper presents an iris indexing technique based on Local Intensity Order Pattern. The performance of the present approach is evaluated on UPOL database and is compared with other recent systems designed for iris indexing. The results illustrate the potential of the proposed method for large scale iris identification.

Iris recognition based on key image feature extraction.

PubMed

Ren, X; Tian, Q; Zhang, J; Wu, S; Zeng, Y

2008-01-01

In iris recognition, feature extraction can be influenced by factors such as illumination and contrast, and thus the features extracted may be unreliable, which can cause a high rate of false results in iris pattern recognition. In order to obtain stable features, an algorithm was proposed in this paper to extract key features of a pattern from multiple images. The proposed algorithm built an iris feature template by extracting key features and performed iris identity enrolment. Simulation results showed that the selected key features have high recognition accuracy on the CASIA Iris Set, where both contrast and illumination variance exist.

The Priority of Road Rehabilitation in Karanganyar Regency Using IRI Estimation from Roadroid

NASA Astrophysics Data System (ADS)

Achmadi, F.; Suprapto, M.; Setyawan, A.

2017-02-01

The IRI (International Roughness Index) is a road roughness index commonly obtained from measured longitudinal road profiles. This is one of the functional performance a surface of road pavement. Therefore, needs to be done evaluation and monitoring periodically to getting priority of road rehabilitation right on target. The IRI standard has commonly been used worldwide for evaluating road system. The Roadroid is an application to measure road quality with a website to view road quality. It is designed for Android smartphones, so we can easily measure and monitor the road and also use the camera for GPS-tagged photo. By using the built-in vibration sensor in smartphones, it is possible to collect IRI value which can be an indicator road conditions. This study attempts to explain the priority of road rehabilitation in Karanganyar Regency. The location of the study focused on a collector street (primary, secondary and locally road). The result of IRI estimation will be combined with other aspects that influences; land use, policy, the connectivity of road and traffic average daily. Based on IRI estimation using Roadroid, the road conditions in Karanganyar Regency can be described 59,60% were good (IRI<4,5) 21,30% fair (4,512).

Simultaneous observations of Ellerman bombs by NST and IRIS

NASA Astrophysics Data System (ADS)

Kim, Y. H.; Yurchyshyn, V.; Cho, I. H.; Lee, J.; Park, Y. D.; Yang, H.; Ahn, K.; Goode, P.

2015-12-01

In this study, we present the simultaneous observations of Ellerman bombs made by New Solar Telescope (NST) of Big Bear Solar Observatory (BBSO) and Interface Region Imaging Spectrograph (IRIS) in space. The data obtained during joint NST-IRIS observations on 30 and 31 in July 2014. We observed two representative events on both days. The first one was a relatively weak Ellerman bomb occurred around 19:20 UT on 30 July 2014. IRIS observed this event by sit-and-stare mode thus we analyzed high cadence spectral data and slit-jaw data simultaneously. We found that this event was a hot explosion that occurred by magnetic reconnection in the lower atmosphere of the Sun. The second event was quite strong Ellerman bomb (20:20 UT on 31 July 2014) that is well observed by NST FISS (Fast Imaging Solar Spectrograph), while there was no IRIS spectral data. We had IRIS slit-jaw data only. The Ellerman bomb was clearly coincident with the IRIS brightening at the same location. Since the Ellerman bombs are usually believed to occur in the photosphere with no coronal emission, it should be explained its higher atmospheric emission in IRIS data. We will present the result of simultaneous observations by IRIS and NST instruments and discuss physical connection between Ellerman bombs and IRIS brightenings.

A novel in vivo model of puncture-induced iris neovascularization

PubMed Central

Aronsson, Monica; Kvanta, Anders

2017-01-01

Purpose To assess iris neovascularization by uveal puncture of the mouse eye and determine the role of angiogenic factors during iris neovascularization. Methods Uveal punctures were performed on BalbC mouse eyes to induce iris angiogenesis. VEGF-blockage was used as an anti-angiogenic treatment, while normoxia- and hypoxia-conditioned media from retinal pigment epithelium (RPE) cells was used as an angiogenic-inducer in this model. Iris vasculature was determined in vivo by noninvasive methods. Iris blood vessels were stained for platelet endothelial cell adhesion molecule-1 and vascular sprouts were counted as markers of angiogenesis. Expression of angiogenic and inflammatory factors in the puncture-induced model were determined by qPCR and western blot. Results Punctures led to increased neovascularization and sprouting of the iris. qPCR and protein analysis showed an increase of angiogenic factors, particularly in the plasminogen-activating receptor and inflammatory systems. VEGF-blockage partly reduced iris neovascularization, and treatment with hypoxia-conditioned RPE medium led to a statistically significant increase in iris neovascularization. Conclusions This study presents the first evidence of a puncture-induced iris angiogenesis model in the mouse. In a broader context, this novel in vivo model of neovascularization has the potential for noninvasive evaluation of angiogenesis modulating substances. PMID:28658313

Iris recognition as a biometric method after cataract surgery

PubMed Central

Roizenblatt, Roberto; Schor, Paulo; Dante, Fabio; Roizenblatt, Jaime; Belfort, Rubens

2004-01-01

Background Biometric methods are security technologies, which use human characteristics for personal identification. Iris recognition systems use iris textures as unique identifiers. This paper presents an analysis of the verification of iris identities after intra-ocular procedures, when individuals were enrolled before the surgery. Methods Fifty-five eyes from fifty-five patients had their irises enrolled before a cataract surgery was performed. They had their irises verified three times before and three times after the procedure, and the Hamming (mathematical) distance of each identification trial was determined, in a controlled ideal biometric environment. The mathematical difference between the iris code before and after the surgery was also compared to a subjective evaluation of the iris anatomy alteration by an experienced surgeon. Results A correlation between visible subjective iris texture alteration and mathematical difference was verified. We found only six cases in which the eye was no more recognizable, but these eyes were later reenrolled. The main anatomical changes that were found in the new impostor eyes are described. Conclusions Cataract surgeries change iris textures in such a way that iris recognition systems, which perform mathematical comparisons of textural biometric features, are able to detect these changes and sometimes even discard a pre-enrolled iris considering it an impostor. In our study, re-enrollment proved to be a feasible procedure. PMID:14748929

Iris recognition as a biometric method after cataract surgery.

PubMed

Roizenblatt, Roberto; Schor, Paulo; Dante, Fabio; Roizenblatt, Jaime; Belfort, Rubens

2004-01-28

Biometric methods are security technologies, which use human characteristics for personal identification. Iris recognition systems use iris textures as unique identifiers. This paper presents an analysis of the verification of iris identities after intra-ocular procedures, when individuals were enrolled before the surgery. Fifty-five eyes from fifty-five patients had their irises enrolled before a cataract surgery was performed. They had their irises verified three times before and three times after the procedure, and the Hamming (mathematical) distance of each identification trial was determined, in a controlled ideal biometric environment. The mathematical difference between the iris code before and after the surgery was also compared to a subjective evaluation of the iris anatomy alteration by an experienced surgeon. A correlation between visible subjective iris texture alteration and mathematical difference was verified. We found only six cases in which the eye was no more recognizable, but these eyes were later reenrolled. The main anatomical changes that were found in the new impostor eyes are described. Cataract surgeries change iris textures in such a way that iris recognition systems, which perform mathematical comparisons of textural biometric features, are able to detect these changes and sometimes even discard a pre-enrolled iris considering it an impostor. In our study, re-enrollment proved to be a feasible procedure.

Role of LTA4H Polymorphism in Tuberculosis-Associated Immune Reconstitution Inflammatory Syndrome Occurrence and Clinical Severity in Patients Infected with HIV.

PubMed

Narendran, Gopalan; Kavitha, Dhanasekaran; Karunaianantham, Ramesh; Gil-Santana, Leonardo; Almeida-Junior, Jilson L; Reddy, Sirasanambatti Devarajulu; Kumar, Marimuthu Makesh; Hemalatha, Haribabu; Jayanthi, Nagesh Nalini; Ravichandran, Narayanan; Krishnaraja, Raja; Prabhakar, Angamuthu; Manoharan, Tamizhselvan; Nithyananthan, Lokeswaran; Arjunan, Gunasundari; Natrajan, Mohan; Swaminathan, Soumya; Andrade, Bruno B

2016-01-01

Paradoxical tuberculosis-associated immune reconstitution inflammatory syndrome (TB-IRIS) is an inflammatory phenomenon complicating HIV management in coincidental tuberculosis (TB) infection, upon immune reconstitution driven by antiretroviral therapy (ART). Leukotriene A4 hydroxylase (LTA4H), an enzyme which converts LTA4 to LTB4, regulates the balance between the anti-inflammatory lipoxins and pro-inflammatory LTB4, with direct implications in TB-driven inflammation. In humans, a single nucleotide polymorphism (SNP) in the LTA4H promoter which regulates its transcriptional activity (rs17525495) has been identified and described to impact clinical severity of TB presentation and response to corticosteroid therapy. Notably, the role of LTA4H on TB-IRIS has not been previously evaluated. Here, we performed an exploratory investigation testing the association of LTA4H polymorphism with respect to frequency of TB-IRIS occurrence and severity of TB-IRIS presentation in HIV-TB co-infected individuals. Genotypic evaluation of the LTA4H enzyme from available samples was retrospectively correlated with clinical data captured in case sheets including IRIS details. The cohort included patients recruited from a prospective cohort study nested within a randomized clinical trial (NCT0933790) of ART-naïve HIV+ patients with newly diagnosed rifampicin sensitive pulmonary TB in South India. Frequency of the wild type genotype (CC), as well as of the mutant genotypes (CT or TT) in the IRIS and non-IRIS patients was estimated. Comparative analyses were performed between wild genotype (CC) and the mutant genotypes (CT or TT) and tested for association between the LTA4H polymorphisms and IRIS incidence and clinical severity. A total of 142 eligible ART-naïve patients were included in the analyses. Eighty-six individuals exhibited the wild genotype (CC) while 56 had mutant genotypes (43-CT and only 13-TT). Variant allele frequency was 0.23 and 0.26 in non-IRIS group and in IRIS group, respectively. Upon ART initiation, 51 patients developed IRIS while 91 did not. IRIS incidence was 34% and 37% in the wild (CC) and mutant type (CT/TT), respectively (p = 0.858) with a higher frequency of severe IRIS presentation in the mutant genotype group compared to the wild type genotype (p = 0.0006). A logistic regression model confirmed the association between the presence of CT/TT genotypes and occurrence of severe IRIS. Corticosteroid therapy successfully resolved IRIS in all cases irrespective of the LTA4H genotype. A higher incidence of severe IRIS among patients with mutant LTA4H genotypes (CT and TT) was observed compared to the wild type, despite similar IRIS incidence and immune restoration in both groups. Steroids were effective in alleviating IRIS in all the genotypes.

The role of BRCA1-IRIS in the development and progression of triple negative breast cancers in Egypt: possible link to disease early lesion.

PubMed

Bogan, Danielle; Meile, Lucio; El Bastawisy, Ahmed; Yousef, Hend F; Zekri, Abdel-Rahman N; Bahnassy, Abeer A; ElShamy, Wael M

2017-05-12

Breast cancer is the most globally diagnosed female cancer, with the triple negative breast cancer (TNBC) being the most aggressive subtype of the disease. In this study we aimed at comparing the effect of BRCA1-IRIS overexpression on the clinico-pathological characteristics in breast cancer patients with TNBC or non-TNBC in the largest comprehensive cancer center in Egypt. To reach this goal, we conducted an observational study at the National Cancer Institute (NCI), Cairo University (Cairo, Egypt). The data on all diagnosed breast cancer patients, between 2009 and 2012, were reviewed. BRCA1-IRIS expression measured using real time RT/PCR in these patients' tumor samples was correlated to tumor characteristics, such as to clinico-pathological features, therapeutic responses, and survival outcomes. 96 patients were enrolled and of these 45% were TNBC, and 55% were of other subtypes (hereafter, non-TNBC). All patients presented with invasive ductal carcinomas. No significant difference was observed for risk factors, such as age and menopausal status between the TNBC and the non-TNBC groups except after BRCA1-IRIS expression was factored in. The majority of the tumors in both groups were ≤5 cm at surgery (p = 0.013). However, in the TNBC group, ≤5 cm tumors were BRCA1-IRIS-overexpressing, whereas in the non-TNBC group they were BRCA1-IRIS-negative (p = 0.00007). Most of the TNBC patients diagnosed with grade 1 or 2 were BRCA1-IRIS-overexpressing, whereas non-TNBCs were IRIS-negative (p = 0.00035). No statistical significance was measured in patients diagnosed with grade 3 tumors. Statistically significant difference between TNBCs and non-TNBCs and tumor stage with regard to BRCA1-IRIS-overexpression was observed. Presence of axillary lymph node metastases was positively associated with BRCA1-IRIS overexpression in TNBC group, and with BRCA1-IRIS-negative status in the non-TNBC group (p = 0.00009). Relapse after chemotherapy (p < 0.00001), and local recurrence/distant metastasis after surgery (p = 0.0028) were more pronounced in TNBC patients with BRCA1-IRIS-overexpressing tumors compared to non-TNBC patients. Finally, decreased disease-free survival in TNBC/BRCA1-IRIS-overexpressing patients compared to TNBC/BRCA1-IRIS-negative patients, and decreased overall survival in TNBC as well as non-TNBC patients was driven by BRCA1-IRIS overexpression. TNBC/BRCA1-IRIS-overexpressing tumors are more aggressive than TNBC/BRCA1-IRIS-negative or non-TNBC/BRCA1-IRIS-overexpressing or both negative tumors. Further studies are warranted to define whether BRCA1-IRIS drives the early TNBC lesions growth and dissemination and whether it could be used as a diagnostic biomarker and/or therapeutic target for these lesions at an early stage setting.

An objective comparison of cell-tracking algorithms.

PubMed

Ulman, Vladimír; Maška, Martin; Magnusson, Klas E G; Ronneberger, Olaf; Haubold, Carsten; Harder, Nathalie; Matula, Pavel; Matula, Petr; Svoboda, David; Radojevic, Miroslav; Smal, Ihor; Rohr, Karl; Jaldén, Joakim; Blau, Helen M; Dzyubachyk, Oleh; Lelieveldt, Boudewijn; Xiao, Pengdong; Li, Yuexiang; Cho, Siu-Yeung; Dufour, Alexandre C; Olivo-Marin, Jean-Christophe; Reyes-Aldasoro, Constantino C; Solis-Lemus, Jose A; Bensch, Robert; Brox, Thomas; Stegmaier, Johannes; Mikut, Ralf; Wolf, Steffen; Hamprecht, Fred A; Esteves, Tiago; Quelhas, Pedro; Demirel, Ömer; Malmström, Lars; Jug, Florian; Tomancak, Pavel; Meijering, Erik; Muñoz-Barrutia, Arrate; Kozubek, Michal; Ortiz-de-Solorzano, Carlos

2017-12-01

We present a combined report on the results of three editions of the Cell Tracking Challenge, an ongoing initiative aimed at promoting the development and objective evaluation of cell segmentation and tracking algorithms. With 21 participating algorithms and a data repository consisting of 13 data sets from various microscopy modalities, the challenge displays today's state-of-the-art methodology in the field. We analyzed the challenge results using performance measures for segmentation and tracking that rank all participating methods. We also analyzed the performance of all of the algorithms in terms of biological measures and practical usability. Although some methods scored high in all technical aspects, none obtained fully correct solutions. We found that methods that either take prior information into account using learning strategies or analyze cells in a global spatiotemporal video context performed better than other methods under the segmentation and tracking scenarios included in the challenge.

Morphological alterations within the peripheral fixation of the iris dilator muscle in eyes with pigmentary glaucoma.

PubMed

Flügel-Koch, Cassandra M; Tektas, Ozan Y; Kaufman, Paul L; Paulsen, Friedrich P; Lütjen-Drecoll, Elke

2014-06-17

To analyze the peripheral fixation of the iris dilator muscle in normal eyes and in eyes with pigmentary glaucoma (PG). Using 63 control eyes (age 18 months-99 years), the peripheral iris dilator was investigated by light microscopy, immunohistochemistry, and electron microscopy. Development was studied using 18 differently aged fetal eyes stained immunohistochemically against α-smooth muscle (SM) actin. The peripheral iris dilator muscle in PG was analyzed using semithin and ultrathin sections of six glutaraldehyde-fixed eyes from three donors aged 38, 62, and 74 years. In normal eyes, the peripheral end of the iris dilator muscle is arranged in a sphincter-like manner. Arcade-shaped tendinous connections associated with myofibroblasts (iridial strands) anchor the iris dilator within the elastic-fibromuscular ciliary meshwork that also serves as fixation area for the elastic tendons of the inner ciliary muscle portions. The iridial strands are innervated and can adapt their length during accommodation. The PG eyes show incomplete circular bundles and iridial strands that are mainly anchored to the iris stroma and the flexible uveal parts of the trabecular meshwork. The normal anchorage of the peripheral iris dilator and its presumably neuronally regulated length adaptation stabilize the peripheral iris during accommodation. Insufficient fixation in PG could promote posterior bowing of the iris with rubbing against the zonular fibers and pigment liberation from the iris pigmented epithelium. Copyright 2014 The Association for Research in Vision and Ophthalmology, Inc.

Coloboma of the iris

MedlinePlus

... enable JavaScript. Coloboma of the iris is a hole or defect of the iris of the eye. Most colobomas are present since birth (congenital). Considerations Coloboma of the iris can look like a second pupil or a black notch at the edge of the pupil. This ...

PLATEAU IRIS – DIAGNOSIS AND TREATMENT

PubMed Central

Stefan, Cornel; Iliescu, Daniela Adriana; Batras, Mehdi; Timaru, Cristina Mihaela; De Simone, Algerino

2015-01-01

Objectives: The objective of our study was to review the current knowledge on the diagnosis and treatment options of plateau iris configuration and syndrome. Systematic review methodology: Relevant publications on plateau iris that were published until 2014. Conclusions: Plateau iris syndrome is a form of primary angle closure glaucoma caused by a large or anteriorly positioned ciliary body that leads to mechanical obstruction of trabecular meshwork. This condition is most often found in younger patients. Plateau iris has been considered an abnormal anatomic variant of the iris that can be diagnosed on ultrasound biomicroscopy or optical coherence tomography of anterior segment. Patients with plateau iris syndrome can be recognized by the lack of response in angle opening after iridotomy. The treatment of choice in these cases is argon laser peripheral iridoplasty PMID:27373109

Self-tracking for Mental Wellness: Understanding Expert Perspectives and Student Experiences

PubMed Central

Kelley, Christina; Lee, Bongshin; Wilcox, Lauren

2017-01-01

Previous research suggests an important role for self-tracking in promoting mental wellness. Recent studies with college student populations have examined the feasibility of collecting everyday mood, activity, and social data. However, these studies do not account for students’ experiences and challenges adopting self-tracking technologies to support mental wellness goals. We present two studies conducted to better understand self-tracking for stress management and mental wellness in student populations. First, focus groups and card sorting activities with 14 student health professionals reveal expert perspectives on the usefulness of tracking for three scenarios. Second, an online survey of 297 students examines personal experiences with self-tracking and attitudes toward sharing self-tracked data with others. We draw on findings from these studies to characterize students’ motivations, challenges, and preferences in collecting and viewing self-tracked data related to mental wellness, and we compare findings between students with diagnosed mental illnesses and those without. We conclude with a discussion of challenges and opportunities in leveraging self-tracking for mental wellness, highlighting several design considerations. PMID:28920106

Transient expansion of activated CD8+ T cells characterizes tuberculosis-associated immune reconstitution inflammatory syndrome in patients with HIV: a case control study

PubMed Central

2013-01-01

Background CD4+ T cell activation indicators have been reported to be a common phenomenon underlying diverse manifestations of immune reconstitution inflammatory syndrome (IRIS). However, we have found that a high frequency of circulating CD8+ T cells is a specific risk factor for mycobacterial IRIS. Therefore, we investigated whether CD8+ T cells from patients who develop TB IRIS were specifically activated. Methods We obtained PBMCs from HIV+ patients prior to and 4, 8, 12, 24, 52 and 104 weeks after initiating antiretroviral therapy. CD38 and HLADR expression on naive, central memory and effector memory CD8+ and CD4+ T cells were determined by flow cytometry. Absolute counts and frequencies of CD8+ T cell subsets were compared between patients who developed TB IRIS, who developed other IRIS forms and who remained IRIS-free. Results TB IRIS patients showed significantly higher counts of naive CD8+ T cells than the other groups at most time points, with a contraction of the effector memory subpopulation occurring later in the follow-up period. Activated (CD38+ HLADR+) CD8+ T cells from all groups decreased with treatment but transiently peaked in TB IRIS patients. This increase was due to an increase in activated naive CD8+ T cell counts during IRIS. Additionally, the CD8+ T cell subpopulations of TB IRIS patients expressed HLADR without CD38 more frequently and expressed CD38 without HLADR less frequently than cells from other groups. Conclusions CD8+ T cell activation is specifically relevant to TB IRIS. Different IRIS forms may involve different alterations in T cell subsets, suggesting different underlying inflammatory processes. PMID:23688318

Comparison of anterior segment optical coherence tomography angiography and fluorescein angiography for iris vasculature analysis.

PubMed

Zett, Claudio; Stina, Deborah M Rosa; Kato, Renata Tiemi; Novais, Eduardo Amorim; Allemann, Norma

2018-04-01

The aim of this study is to perform imaging of irises of different colors using spectral domain anterior segment optical coherence tomography angiography (AS-OCTA) and iris fluorescein angiography (IFA) and compare their effectiveness in examining iris vasculature. This is a cross-sectional observational clinical study. Patients with no vascular iris alterations and different pigmentation levels were recruited. Participants were imaged using OCTA adapted with an anterior segment lens and IFA with a confocal scanning laser ophthalmoscope (cSLO) adapted with an anterior segment lens. AS-OCTA and IFA images were then compared. Two blinded readers classified iris pigmentation and compared the percentage of visible vessels between OCTA and IFA images. Twenty eyes of 10 patients with different degrees of iris pigmentation were imaged using AS-OCTA and IFA. Significantly more visible iris vessels were observed using OCTA than using FA (W = 5.22; p < 0.001). Iris pigmentation was negatively correlated to the percentage of visible vessels in both imaging methods (OCTA, rho = - 0.73, p < 0.001; IFA, rho = - 0.77, p < 0.001). Unlike FA, AS-OCTA could not detect leakage of dye, delay, or impregnation. Nystagmus and inadequate fixation along with motion artifacts resulted in lower quality images in AS-OCTA than in IFA. AS-OCTA is a new imaging modality which allows analysis of iris vasculature. In both AS-OCTA and IFA, iris pigmentation caused vasculature imaging blockage, but AS-OCTA provided more detailed iris vasculature images than IFA. Additional studies including different iris pathologies are needed to determine the most optimal scanning parameters in OCTA of the anterior segment.

[Comparative clinical study of wavefront-guided laser in situ keratomileusis with versus without iris recognition for myopia or myopic astigmatism].

PubMed

Wang, Wei-qun; Zhang, Jin-song; Zhao, Xiao-jin

2011-10-01

To explore the postoperative visual acuity results of wavefront-guided LASIK with iris recognition for myopia or myopic astigmatism and the changes of higher-order aberrations and contrast sensitivity function (CSF). Series of prospective case studies, 158 eyes (85 cases) of myopia or myopic astigmatism were divided into two groups: one group underwent wavefront-guided LASIK with iris recognition (iris recognition group); another group underwent wavefront-guided LASIK treatment without iris recognition through the limbus maring point (non-iris recognition group). To comparative analyze the postoperative visual acuity, residual refraction, the RMS of higher-order aberrations and CSF of two groups. There was no statistical significance difference between two groups of the average uncorrected visual acuity (t = 0.039, 0.058, 0.898; P = 0.844, 0.810, 0.343), best corrected visual acuity (t = 0.320, 0.440, 1.515; P = 0.572, 0.507, 0.218), and residual refraction [spherical equivalent (t = 0.027, 0.215, 0.238; P = 0.869, 0.643, 0.626), spherical (t = 0.145, 0.117, 0.038; P = 0.704, 0.732, 0.845) and cylinder (t = 1.676, 1.936, 0.334; P = 0.195, 0.164, 0.563)] at postoperative 10 days, 1 month and 3 month. The security index of iris recognition group at postoperative 3 month was 1.06 and non-iris recognition group was 1.03; the efficacy index of iris recognition group is 1.01 and non-iris recognition group was 1.00. Postoperative 3 month iris recognition group 93.83% eyes and non-iris recognition group of 90.91% eyes spherical equivalent within ± 0.50 D (χ(2) = 0.479, P = 0.489), iris recognition group of 98.77% eyes and non-iris recognition group of 97.40% eyes spherical equivalent within ± 1.00 D (Fisher test, P = 0.613). There was no significance difference between the two groups of security, efficacy and predictability. Non-iris recognition group postoperative 1 month and postoperative 3 months 3-order order aberrations root mean square value (RMS) higher than the iris recognition group increased (t = 3.414, -2.870; P = 0.027, 0.045), in particular of coma; the general higher-order aberrations (t = 0.386, 1.132; P = 0.719, 0.321), 4-order aberrations (t = 0.808, 2.720; P = 0.464, 0.063), and 5-order aberrations (t = 0.148, -1.717; P = 0.890, 0.161) show no statistically significant difference. Three months after surgery, two groups have recovered at all spatial frequencies of CSF, iris recognition group at 3.0 c/d (t = 3.209, P = 0.002) and 6.0 c/d (t = 2.997, P = 0.004) spatial frequencies of CSF under mesopic condition was better than non-iris recognition group, glare contrast sensitivity function (GCSF) for 3.0 c/d (t = 3.423, P = 0.001) and 6.0 c/d (t = 6.986, P = 0.000) spatial frequencies under mesopic condition and 1.5 c/d (t = 9.839, P = 0.000) and 3.0 c/d (t = 7.367, P = 0.000) spatial frequencies under photopic condition in iris recognition group were better than non-iris recognition group, there were no significant difference between two groups at the other spatial frequencies. Wavefront-guided LASIK with or without iris recognition both acquired better postoperative visual acuity, but in comparison with without iris recognition, wavefront-guided LASIK with iris recognition is efficient to reduce coma and enhance contrast sensitivity of postoperative.

Improved iris localization by using wide and narrow field of view cameras for iris recognition

NASA Astrophysics Data System (ADS)

Kim, Yeong Gon; Shin, Kwang Yong; Park, Kang Ryoung

2013-10-01

Biometrics is a method of identifying individuals by their physiological or behavioral characteristics. Among other biometric identifiers, iris recognition has been widely used for various applications that require a high level of security. When a conventional iris recognition camera is used, the size and position of the iris region in a captured image vary according to the X, Y positions of a user's eye and the Z distance between a user and the camera. Therefore, the searching area of the iris detection algorithm is increased, which can inevitably decrease both the detection speed and accuracy. To solve these problems, we propose a new method of iris localization that uses wide field of view (WFOV) and narrow field of view (NFOV) cameras. Our study is new as compared to previous studies in the following four ways. First, the device used in our research acquires three images, one each of the face and both irises, using one WFOV and two NFOV cameras simultaneously. The relation between the WFOV and NFOV cameras is determined by simple geometric transformation without complex calibration. Second, the Z distance (between a user's eye and the iris camera) is estimated based on the iris size in the WFOV image and anthropometric data of the size of the human iris. Third, the accuracy of the geometric transformation between the WFOV and NFOV cameras is enhanced by using multiple matrices of the transformation according to the Z distance. Fourth, the searching region for iris localization in the NFOV image is significantly reduced based on the detected iris region in the WFOV image and the matrix of geometric transformation corresponding to the estimated Z distance. Experimental results showed that the performance of the proposed iris localization method is better than that of conventional methods in terms of accuracy and processing time.

Differences in iris thickness among African Americans, Caucasian Americans, Hispanic Americans, Chinese Americans, and Filipino-Americans.

PubMed

Lee, Roland Y; Huang, Guofu; Porco, Travis C; Chen, Yi-Chun; He, Mingguang; Lin, Shan C

2013-12-01

To evaluate the capability of iris thickness parameters to explain the difference in primary angle-closure glaucoma prevalence among the different racial groups. In this prospective study, 436 patients with open and narrow angles that met inclusion criteria were consecutively recruited from the UCSF general ophthalmology and glaucoma clinics to receive anterior segment optical coherence tomography imaging under standardized dark conditions. Images from 11 patients were removed due to poor visibility of the scleral spurs and the remaining images were analyzed using the Zhongshan Angle Assessment Program to assess the following measurements for the nasal and temporal angle of the anterior chamber: iris thickness at 750 and 2000 μm from the scleral spurs and the maximum iris thickness at middle one third of the iris. Iris thickness parameters were compared among and within the following 5 different racial groups: African Americans, Caucasian Americans, Hispanic Americans, Chinese Americans, and Filipino-Americans. In comparing iris parameters among the open-angle racial groups, significant differences were found for nasal iris thickness at 750 and 2000 μm from the scleral spurs in which Chinese Americans displayed the highest mean value (P=0.01, P<0.0001). Among the narrow-angle racial groups, significant difference was found for nasal iris thickness at 2000 μm from the scleral in which Chinese Americans showed the highest mean value (P<0.0001). Significant difference was also found for temporal maximum iris thickness at middle one third of the iris in which African Americans exhibited the highest mean value (P=0.021). Iris thickness was modeled as a function of angle status using linear mixed-effects regression, adjusting for age, sex, pupil diameter, spherical equivalent, ethnicity, and the use of both eyes in patients. The iris thickness difference between the narrow-angle and open-angle groups was significant (P=0.0007). Racial groups that historically showed higher prevalence of primary angle-closure glaucoma possess thicker irides.

Iris Damage Is Associated With Elevated Cytokine Levels in Aqueous Humor.

PubMed

Aketa, Naohiko; Yamaguchi, Takefumi; Suzuki, Terumasa; Higa, Kazunari; Yagi-Yaguchi, Yukari; Satake, Yoshiyuki; Tsubota, Kazuo; Shimazaki, Jun

2017-05-01

To evaluate the association between iris damage and cytokine levels in the aqueous humor (AqH). A total of 201 AqH samples from 201 consecutive patients (mean age 73.7 ± 10.6) were collected at the beginning of corneal transplantation or cataract surgery. Iris damage of each case was assessed from preoperative slit-lamp findings based on its severity. The subjects were classified into three groups: eyes without iris damage (126 eyes), eyes with mild iris damage (51 eyes), and eyes with severe iris damage (24 eyes). The levels of cytokines (IL-1α, IL-1β, IL-4, IL-6, IL-8, IL-10, IL-12p70, IL-13, IL-17a, interferon gamma-induced protein [IP]-10, monocyte chemotactic protein [MCP]-1, IFN-α, IFN-γ, macrophage inflammatory protein [MIP]-1α, MIP-1β, P-selectin, E-selectin, soluble intercellular adhesion molecule [sICAM]-1, TNF-α, and granulocyte-macrophage colony-stimulating factor [GM-CSF]) in AqH were measured by multiplex beads immunoassay. The levels of aqueous protein, IL-1α, IL-1β, IL-4, IL-6, IL-8, IL-10, IL-17A, MCP-1, TNF-α, E-selectin, P-selectin, and sICAM-1 in eyes with mild and severe iris damage were higher than in those without iris damage (P < 0.033). Multivariate analyses of clinical factors revealed that iris damage was associated with the history of complicated glaucoma, and the number of previous intraocular surgeries. The levels of AqH IL-6, IL-8, IL-13, MIP-1α, TNF-α, and sICAM-1 were significantly elevated in eyes with mild and severe iris damage in phakic eyes, and the levels of AqH IL-8 and sICAM-1 were significantly elevated in eyes with severe iris damage in pseudophakic eyes, compared with the eyes without iris damage (P < 0.045). Iris damage was associated with the elevation in the levels of aqueous protein and cytokines.

IRIS Toxicological Review of Ethyl Tertiary Butyl Ether (ETBE) (Public Comment Draft)

EPA Science Inventory

In September 2016, the U.S. Environmental Protection Agency's (USEPA) released the draft Integrated Risk Information System (IRIS) Toxicological Review of Ethyl Tertiary Butyl Ether (ETBE). Consistent with the 2013 IRIS Enhancements, draft IRIS assessments are released prior to e...

IRIS TOXICOLOGICAL REVIEW AND SUMMARY DOCUMENTS FOR BERYLLIUM AND COMPOUNDS

EPA Science Inventory

EPA's assessment of the noncancer health effects and carcinogenic potential of Beryllium was added to the IRIS database in 1998. The IRIS program is updating the IRIS assessment for Beryllium. This update will incorporate health effects information published since the last assess...

78 FR 18426 - Proposed Information Collection (IRIS) Activity; Comment Request

Federal Register 2010, 2011, 2012, 2013, 2014

2013-03-26

... DEPARTMENT OF VETERANS AFFAIRS [OMB Control No. 2900-0619] Proposed Information Collection (IRIS... through the Inquiry Routing and Information System (IRIS). DATES: Written comments and recommendations on... information technology. Title: Inquiry Routing and Information System (IRIS), VA Form 0873. OMB Control Number...

Deep learning architecture for iris recognition based on optimal Gabor filters and deep belief network

NASA Astrophysics Data System (ADS)

He, Fei; Han, Ye; Wang, Han; Ji, Jinchao; Liu, Yuanning; Ma, Zhiqiang

2017-03-01

Gabor filters are widely utilized to detect iris texture information in several state-of-the-art iris recognition systems. However, the proper Gabor kernels and the generative pattern of iris Gabor features need to be predetermined in application. The traditional empirical Gabor filters and shallow iris encoding ways are incapable of dealing with such complex variations in iris imaging including illumination, aging, deformation, and device variations. Thereby, an adaptive Gabor filter selection strategy and deep learning architecture are presented. We first employ particle swarm optimization approach and its binary version to define a set of data-driven Gabor kernels for fitting the most informative filtering bands, and then capture complex pattern from the optimal Gabor filtered coefficients by a trained deep belief network. A succession of comparative experiments validate that our optimal Gabor filters may produce more distinctive Gabor coefficients and our iris deep representations be more robust and stable than traditional iris Gabor codes. Furthermore, the depth and scales of the deep learning architecture are also discussed.

The International Reference Ionosphere - Status 2013

NASA Astrophysics Data System (ADS)

Bilitza, Dieter

2015-04-01

This paper describes the latest version of the International Reference Ionosphere (IRI) model. IRI-2012 includes new models for the electron density and ion densities in the region below the F-peak, a storm-time model for the auroral E-region, an improved electron temperature model that includes variations with solar activity, and for the first time a description of auroral boundaries. In addition, the thermosphere model required for baseline neutral densities and temperatures was upgraded from MSIS-86 to the newer NRLMSIS-00 model and Corrected Geomagnetic coordinates (CGM) were included in IRI as an additional coordinate system for a better representation of auroral and polar latitudes. Ongoing IRI activities towards the inclusion of an improved model for the F2 peak height hmF2 are discussed as are efforts to develop a "Real-Time IRI". The paper is based on an IRI status report presented at the 2013 IRI Workshop in Olsztyn, Poland. The IRI homepage is at

[Evaluation of Iris Morphology Viewed through Stromal Edematous Corneas by Infrared Camera].

PubMed

Kobayashi, Masaaki; Morishige, Naoyuki; Morita, Yukiko; Yamada, Naoyuki; Kobayashi, Motomi; Sonoda, Koh-Hei

2016-02-01

We reported that the application of infrared camera enables us to observe iris morphology in Peters' anomaly through edematous corneas. To observe the iris morphology in bullous keratopathy or failure grafts with an infrared camera. Eleven bullous keratopathy or failure grafts subjects (6 men and 5 women, mean age ± SD; 72.7 ± 13.0 years old) were enrolled in this study. The iris morphology was observed by applying visible light mode and near infrared light mode of infrared camera (MeibomPen). The detectability of pupil shapes, iris patterns and presence of iridectomy was evaluated. Infrared mode observation enabled us to detect the pupil shapes in 11 out of 11 cases, iris patterns in 3 out of 11 cases, and presence of iridetomy in 9 out of 11 cases although visible light mode observation could not detect any iris morphological changes. Applying infrared optics was valuable for observation of the iris morphology through stromal edematous corneas.

Intracellular cytoskeleton and junction proteins of endothelial cells in the porcine iris microvasculature.

PubMed

Yang, Hongfang; Yu, Paula K; Cringle, Stephen J; Sun, Xinghuai; Yu, Dao-Yi

2015-11-01

Recently we reported studies of the iris microvasculature and its endothelial cells using intra-luminal micro-perfusion, fixation, and silver staining, suggesting that the iris vascular endothelium may be crucial for maintaining homeostasis in the ocular anterior segment. Here we present information regarding the intracellular structure and cell junctions of the iris endothelium. Thirty-seven porcine eyes were used for this study. The temporal long posterior ciliary artery was cannulated to assess the iris microvascular network and its endothelium using intra-luminal micro-perfusion, fixation, and staining with phalloidin for intracellular cytoskeleton f-actin, and with antibodies against claudin-5 and VE-cadherin for junction proteins. Nuclei were counterstained with Hoechst. The iris was flat-mounted for confocal imaging. The iris microvasculature was studied for its distribution, branch orders and endothelial morphometrics with endothelial cell length measured for each vessel order. Our results showed that morphometrics of the iris microvasculature was comparable with our previous silver staining. Abundant stress fibres and peripheral border staining were seen within the endothelial cells in larger arteries. An obvious decrease in cytoplasmic stress fibres was evident further downstream in the smaller arterioles, and they tended to be absent from capillaries and veins. Endothelial intercellular junctions throughout the iris vasculature were VE-cadherin and claudin-5 immuno-positive, indicating the presence of both adherent junctions and tight junctions between vascular endothelial cells throughout the iris microvasculature. Unevenness of claudin-5 staining was noted along the endothelial cell borders in almost every order of vessels, especially in veins and small arterioles. Our results suggest that significant heterogeneity of intracellular structure and junction proteins is present in different orders of the iris vasculature in addition to vascular diameter and shape of the endothelia. Detailed information of the topography and intracellular structure and junction proteins of the endothelium of the iris microvasculature combined with unique structural features of the iris may help us to further understand the physiological and pathogenic roles of the iris vasculature in relevant ocular diseases. Copyright © 2015 Elsevier Ltd. All rights reserved.

In vivo analysis of the iris thickness by spectral domain optical coherence tomography.

PubMed

Invernizzi, Alessandro; Cigada, Mario; Savoldi, Luisa; Cavuto, Silvio; Fontana, Luigi; Cimino, Luca

2014-09-01

To assess the effectiveness of spectral domain optical coherence tomography (SD-OCT) in providing in vivo measurements of iris thickness in healthy and pathological subjects. 14 healthy volunteers and 14 patients with unilateral Fuchs' uveitis were enrolled in the study. The two groups were comparable for age, gender and race. Each subject underwent complete clinical examination and anterior segment SD-OCT imaging in both eyes. SD-OCT scans of the iris were performed following a cross-sectional pattern. Iris thickness values were obtained using a purposely developed software-based analysis of OCT images. Measurements were carried out twice by two trained independent operators to assess intraobserver and interobserver repeatability. Analysis of iris thickness was conducted in four main quadrants: superior, inferior, nasal and temporal. Iris thickness values from normal subjects were compared with the ones measured in the affected and fellow eyes of patients with Fuchs' uveitis. Iris thickness measurements showed good intraobserver and interobserver repeatability (intraclass correlation coefficient >0.971). Superior and temporal iris sectors showed respectively thickest and thinnest values in all groups. In healthy eyes, iris thickness ranged from 327.92±37.29 μm temporally to 405.25±48.49 μm superiorly. Iris thickness measurements in the affected eyes of Fuchs' uveitis patients ranged from 285.48±56.02 μm temporally to 376.12±60.97 μm superiorly. Multiple comparison analysis showed iris thickness values to be significantly lower in eyes affected by Fuchs' uveitis than both in fellow eyes (p<0.001) of the same patients and in healthy eyes (p=0.0074). SD-OCT is a suitable technique for iris thickness assessment. Thickness analysis must be carried out using a sectorial approach, taking into consideration anatomical variations existing between different iris regions. SD-OCT is a potentially useful tool for detecting iris thickness variations induced by pathological conditions such as Fuchs' uveitis. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Porcine cadaver iris model for iris heating during corneal surgery with a femtosecond laser

NASA Astrophysics Data System (ADS)

Sun, Hui; Fan, Zhongwei; Wang, Jiang; Yan, Ying; Juhasz, Tibor; Kurtz, Ron

2015-03-01

Multiple femtosecond lasers have now been cleared for use for ophthalmic surgery, including for creation of corneal flaps in LASIK surgery. Preliminary study indicated that during typical surgical use, laser energy may pass beyond the cornea with potential effects on the iris. As a model for laser exposure of the iris during femtosecond corneal surgery, we simulated the temperature rise in porcine cadaver iris during direct illumination by the femtosecond laser. Additionally, ex-vivo iris heating due to femtosecond laser irradiation was measured with an infrared thermal camera (Fluke corp. Everett, WA) as a validation of the simulation.

Extending Iris: The VAO SED Analysis Tool

NASA Astrophysics Data System (ADS)

Laurino, O.; Busko, I.; Cresitello-Dittmar, M.; D'Abrusco, R.; Doe, S.; Evans, J.; Pevunova, O.

2013-10-01

Iris is a tool developed by the Virtual Astronomical Observatory (VAO) for building and analyzing Spectral Energy Distributions (SEDs). Iris was designed to be extensible, so that new components and models can be developed by third parties and then included at runtime. Iris can be extended in different ways: new file readers allow users to integrate data in custom formats into Iris SEDs; new models can be fitted to the data, in the form of template libraries for template fitting, data tables, and arbitrary Python functions. The interoperability-centered design of Iris and the Virtual Observatory standards and protocols can enable new science functionalities involving SED data.

Using crypts as iris minutiae

NASA Astrophysics Data System (ADS)

Shen, Feng; Flynn, Patrick J.

2013-05-01

Iris recognition is one of the most reliable biometric technologies for identity recognition and verification, but it has not been used in a forensic context because the representation and matching of iris features are not straightforward for traditional iris recognition techniques. In this paper we concentrate on the iris crypt as a visible feature used to represent the characteristics of irises in a similar way to fingerprint minutiae. The matching of crypts is based on their appearances and locations. The number of matching crypt pairs found between two irises can be used for identity verification and the convenience of manual inspection makes iris crypts a potential candidate for forensic applications.

IRIS Toxicological Review of Ammonia Noncancer Inhalation ...

EPA Pesticide Factsheets

In September 2016, EPA finalized the IRIS assessment of Ammonia (Noncancer Inhalation). The Toxicological Review was reviewed internally by EPA and by other federal agencies and White House Offices before public release in June 2016. Consistent with the May 2009 IRIS assessment development process, all written comments on IRIS assessments submitted by other federal agencies and White House Offices are made publicly available. Accordingly, interagency comments and the interagency science discussion materials provided to other agencies, including interagency review drafts of the IRIS Toxicological Review of Ammonia (Noncancer Inhalation) are posted on this site. Note: No major science comments were received on the Interagency Science Discussion Draft. EPA is undertaking an Integrated Risk Information System (IRIS) health assessment for ammonia. IRIS is an EPA database containing Agency scientific positions on potential adverse human health effects that may result from chronic (or lifetime) exposure to chemicals in the environment. IRIS contains chemical-specific summaries of qualitative and quantitative health information in support of two steps of the risk assessment paradigm, i.e., hazard identification and dose-response evaluation. IRIS assessments are used in combination with specific situational exposure assessment information to evaluate potential public health risk associated with environmental contaminants.

Iridoschisis: high frequency ultrasound imaging. Evidence for a genetic defect?

PubMed Central

Danias, J; Aslanides, I M; Eichenbaum, J W; Silverman, R H; Reinstein, D Z; Coleman, D J

1996-01-01

AIMS: To elucidate changes in the anatomy of the anterior chamber associated with iridoschisis, a rare form of iris atrophy, and their potential contribution to angle closure glaucoma. METHODS: Both eyes of a 71-year-old woman with bilateral iridoschisis and fibrous dysplasia and her asymptomatic 50-year-old daughter were scanned with a very high frequency (50 MHz) ultrasound system. RESULTS: The symptomatic patient exhibited diffuse changes in the iris stoma with an intact posterior iris pigmented layer in both eyes. These changes were clinically compatible with the lack of iris transillumination defects. Additionally, iris bowing with a resultant narrowing of the angle occurred. The asymptomatic daughter showed discrete, but less severe iris stromal changes. CONCLUSION: This is the first detailed study of high frequency ultrasonic imaging of the iris in iridoschisis. The observed structural changes suggest angle narrowing by forward bowing of the anterior iris stroma may be a mechanism of IOP elevation in this condition. The ultrasonic detection of iris changes in the asymptomatic daughter of the symptomatic patient and the association of iridoschisis with fibrous dysplasia suggest a possible genetic component in the pathogenesis of this condition. Images PMID:9059271

Iris-based medical analysis by geometric deformation features.

PubMed

Ma, Lin; Zhang, D; Li, Naimin; Cai, Yan; Zuo, Wangmeng; Wang, Kuanguan

2013-01-01

Iris analysis studies the relationship between human health and changes in the anatomy of the iris. Apart from the fact that iris recognition focuses on modeling the overall structure of the iris, iris diagnosis emphasizes the detecting and analyzing of local variations in the characteristics of irises. This paper focuses on studying the geometrical structure changes in irises that are caused by gastrointestinal diseases, and on measuring the observable deformations in the geometrical structures of irises that are related to roundness, diameter and other geometric forms of the pupil and the collarette. Pupil and collarette based features are defined and extracted. A series of experiments are implemented on our experimental pathological iris database, including manual clustering of both normal and pathological iris images, manual classification by non-specialists, manual classification by individuals with a medical background, classification ability verification for the proposed features, and disease recognition by applying the proposed features. The results prove the effectiveness and clinical diagnostic significance of the proposed features and a reliable recognition performance for automatic disease diagnosis. Our research results offer a novel systematic perspective for iridology studies and promote the progress of both theoretical and practical work in iris diagnosis.

Iris: Constructing and Analyzing Spectral Energy Distributions with the Virtual Observatory

NASA Astrophysics Data System (ADS)

Laurino, O.; Budynkiewicz, J.; Busko, I.; Cresitello-Dittmar, M.; D'Abrusco, R.; Doe, S.; Evans, J.; Pevunova, O.

2014-05-01

We present Iris 2.0, the latest release of the Virtual Astronomical Observatory application for building and analyzing Spectral Energy Distributions (SEDs). With Iris, users may read in and display SEDs inspect and edit any selection of SED data, fit models to SEDs in arbitrary spectral ranges, and calculate confidence limits on best-fit parameters. SED data may be loaded into the application from VOTable and FITS files compliant with the International Virtual Observatoy Alliance interoperable data models, or retrieved directly from NED or the Italian Space Agency Science Data Center; data in non-standard formats may also be converted within the application. Users may seamlessy exchange data between Iris and other Virtual Observatoy tools using the Simple Application Messaging Protocol. Iris 2.0 also provides a tool for redshifting, interpolating, and measuring integratd fluxes, and allows simple aperture corrections for individual points and SED segments. Custom Python functions, template models and template libraries may be imported into Iris for fitting SEDs. Iris may be extended through Java plugins; users can install third-party packages, or develop their own plugin using Iris' Software Development Kit. Iris 2.0 is available for Linux and Mac OS X systems.

Eclipse-Free-Time Assessment Tool for IRIS

NASA Technical Reports Server (NTRS)

Eagle, David

2012-01-01

IRIS_EFT is a scientific simulation that can be used to perform an Eclipse-Free- Time (EFT) assessment of IRIS (Infrared Imaging Surveyor) mission orbits. EFT is defined to be those time intervals longer than one day during which the IRIS spacecraft is not in the Earth s shadow. Program IRIS_EFT implements a special perturbation of orbital motion to numerically integrate Cowell's form of the system of differential equations. Shadow conditions are predicted by embedding this integrator within Brent s method for finding the root of a nonlinear equation. The IRIS_EFT software models the effects of the following types of orbit perturbations on the long-term evolution and shadow characteristics of IRIS mission orbits. (1) Non-spherical Earth gravity, (2) Atmospheric drag, (3) Point-mass gravity of the Sun, and (4) Point-mass gravity of the Moon. The objective of this effort was to create an in-house computer program that would perform eclipse-free-time analysis. of candidate IRIS spacecraft mission orbits in an accurate and timely fashion. The software is a suite of Fortran subroutines and data files organized as a "computational" engine that is used to accurately predict the long-term orbit evolution of IRIS mission orbits while searching for Earth shadow conditions.

IRIS TOXICOLOGICAL REVIEW AND SUMMARY DOCUMENTS FOR 1,2,3-TRICHLOROPROPANE

EPA Science Inventory

EPA's assessment of the noncancer health effects and carcinogenic potential of 1,2,3-trichloropropane (TCP) was added to the IRIS database in 1990. The IRIS program is updating the IRIS assessment for TCP. This update will incorporate health effects information published since t...

75 FR 28856 - Agency Information Collection (IRIS) Activities Under OMB Review

Federal Register 2010, 2011, 2012, 2013, 2014

2010-05-24

... DEPARTMENT OF VETERANS AFFAIRS [OMB Control No. 2900-0619] Agency Information Collection (IRIS... Information System (IRIS). OMB Control Number: 2900-0619. Type of Review: Extension of a currently approved... veterans, dependents, and active duty personnel worldwide. IRIS allows a customer to submit questions...

75 FR 13208 - Proposed Information Collection (IRIS) Activity; Comment Request

Federal Register 2010, 2011, 2012, 2013, 2014

2010-03-18

... DEPARTMENT OF VETERANS AFFAIRS [OMB Control No. 2900-0619] Proposed Information Collection (IRIS... submitted to VA through the Inquiry Routing and Information System (IRIS). DATES: Written comments and... (IRIS), VA Form 0873. OMB Control Number: 2900-0619. Type of Review: Extension of a currently approved...

Implantation of ArtificialIris, a CustomFlex irisprosthesis, in a trauma patient with an Artisan lens

PubMed Central

Doroodgar, Farideh; Jabbarvand, Mahmoud; Niazi, Feizollah; Niazi, Sana; Sanginabadi, Azad

2017-01-01

Abstract Purpose: To evaluate probable complications of ArtificialIris implantation with iris fixated intraocular lens. Method: Development of photophobia, glare, and psychological strain during face-to-face communication in a 23-year-old man with a widespread traumatic iris defect terminate to make a decision for performing implantation of an ArtificialIris (Humanoptics, Erlangen, Germany) under the remnant iris without removing the patient's existing Artisan lens. Results: Without any intraoperative or postoperative complications, the patient's visual acuity increased by 1 line, the endothelial cell loss was comparable with the cell loss associated with standard cataract surgery, and the anterior-chamber depth and anterior-chamber anatomy did not change. At the final follow-up examination, the mean intraocular pressure did not differ from baseline, and we achieved high level of patient satisfaction and subjective vision improvement. We discuss the particular importance of considering the patient's expectations, the appropriate measurements, ways to perfect color evaluation, and the types of ArtificialIris products. Conclusion: The implantation of the ArtificialIris in patients with aphakic iris-supported lenses (ie, pre-existing Artisan lenses) is a feasible approach and a useful option for patients with thin irises and iris hypoplasia who are at risk of subluxation or the dislocation of the posterior-chamber intraocular lens (PCIOL), and also those with sclerally fixed PCIOLs. PMID:29137026

Role of LTA4H Polymorphism in Tuberculosis-Associated Immune Reconstitution Inflammatory Syndrome Occurrence and Clinical Severity in Patients Infected with HIV

PubMed Central

Narendran, Gopalan; Kavitha, Dhanasekaran; Karunaianantham, Ramesh; Gil-Santana, Leonardo; Almeida-Junior, Jilson L.; Reddy, Sirasanambatti Devarajulu; Kumar, Marimuthu Makesh; Hemalatha, Haribabu; Jayanthi, Nagesh Nalini; Ravichandran, Narayanan; Krishnaraja, Raja; Prabhakar, Angamuthu; Manoharan, Tamizhselvan; Nithyananthan, Lokeswaran; Arjunan, Gunasundari; Natrajan, Mohan; Swaminathan, Soumya

2016-01-01

Background Paradoxical tuberculosis-associated immune reconstitution inflammatory syndrome (TB-IRIS) is an inflammatory phenomenon complicating HIV management in coincidental tuberculosis (TB) infection, upon immune reconstitution driven by antiretroviral therapy (ART). Leukotriene A4 hydroxylase (LTA4H), an enzyme which converts LTA4 to LTB4, regulates the balance between the anti-inflammatory lipoxins and pro-inflammatory LTB4, with direct implications in TB-driven inflammation. In humans, a single nucleotide polymorphism (SNP) in the LTA4H promoter which regulates its transcriptional activity (rs17525495) has been identified and described to impact clinical severity of TB presentation and response to corticosteroid therapy. Notably, the role of LTA4H on TB-IRIS has not been previously evaluated. Here, we performed an exploratory investigation testing the association of LTA4H polymorphism with respect to frequency of TB-IRIS occurrence and severity of TB-IRIS presentation in HIV-TB co-infected individuals. Methods Genotypic evaluation of the LTA4H enzyme from available samples was retrospectively correlated with clinical data captured in case sheets including IRIS details. The cohort included patients recruited from a prospective cohort study nested within a randomized clinical trial (NCT0933790) of ART-naïve HIV+ patients with newly diagnosed rifampicin sensitive pulmonary TB in South India. Frequency of the wild type genotype (CC), as well as of the mutant genotypes (CT or TT) in the IRIS and non-IRIS patients was estimated. Comparative analyses were performed between wild genotype (CC) and the mutant genotypes (CT or TT) and tested for association between the LTA4H polymorphisms and IRIS incidence and clinical severity. Results A total of 142 eligible ART-naïve patients were included in the analyses. Eighty-six individuals exhibited the wild genotype (CC) while 56 had mutant genotypes (43-CT and only 13-TT). Variant allele frequency was 0.23 and 0.26 in non-IRIS group and in IRIS group, respectively. Upon ART initiation, 51 patients developed IRIS while 91 did not. IRIS incidence was 34% and 37% in the wild (CC) and mutant type (CT/TT), respectively (p = 0.858) with a higher frequency of severe IRIS presentation in the mutant genotype group compared to the wild type genotype (p = 0.0006). A logistic regression model confirmed the association between the presence of CT/TT genotypes and occurrence of severe IRIS. Corticosteroid therapy successfully resolved IRIS in all cases irrespective of the LTA4H genotype. Conclusion A higher incidence of severe IRIS among patients with mutant LTA4H genotypes (CT and TT) was observed compared to the wild type, despite similar IRIS incidence and immune restoration in both groups. Steroids were effective in alleviating IRIS in all the genotypes. PMID:27643598

Qualitative Assessment of Ultrasound Biomicroscopic Images Using Standard Photographs: The Liwan Eye Study

PubMed Central

Jiang, Yuzhen; Huang, Wenyong; Huang, Qunxiao; Zhang, Jian; Foster, Paul J.

2010-01-01

Objective. To classify anatomic features related to anterior chamber angles by a qualitative assessment system based on ultrasound biomicroscopy (UBM) images. Methods. Cases of primary angle-closure suspect (PACS), defined by pigmented trabecular meshwork that is not visible in two or more quadrants on static gonioscopy (cases) and systematically selected subjects (1 of every 10) who did not meet this criterion (controls) were enrolled during a population-based survey in Guangzhou, China. All subjects underwent UBM examination. A set of standard UBM images was used to qualitatively classify anatomic features related to the angle configuration, including iris thickness, iris convexity, iris angulation, ciliary body size, and ciliary process position. All analysis was conducted on right eye images. Results. Based on the qualitative grades, the difference in overall iris thickness between gonioscopically narrow eyes (n = 117) and control eyes (n = 57) was not statistically significant. The peripheral one third of the iris tended to be thicker in all quadrants of the PACS eyes, although the difference was statistically significant only in the superior quadrant (P = 0.008). No significant differences were found in the qualitative classifications of iris insertion, iris angulation, ciliary body size, and ciliary process position. The findings were similar when compared with the control group of eyes with wide angles in all quadrants. Conclusions. Basal iris thickness seems to be more relevant to narrow angle configuration than to overall iris thickness. Otherwise, the anterior rotation and size of the ciliary body, the iris insertion, and the overall iris thickness are comparable in narrow- and wide-angle eyes. PMID:19834039

The concave iris in pigment dispersion syndrome.

PubMed

Liu, Lance; Ong, Ee Lin; Crowston, Jonathan

2011-01-01

To visualize the changes of the iris contour in patients with pigment dispersion syndrome after blinking, accommodation, and pharmacologic miosis using anterior segment optical coherence tomography. Observational case series. A total of 33 eyes of 20 patients with pigment dispersion syndrome. Each eye was imaged along the horizontal 0- to 180-degree meridian using the Visante Anterior Segment Imaging System (Carl Zeiss Meditec, Dublin, CA). Scans were performed at baseline and after focusing on an internal fixation target for 5 minutes, forced blinking, accommodation, and pharmacologic miosis with pilocarpine 2%. Quantitative analysis of the changes in the iris configuration. After 5 minutes of continual fixation, the iris became planar with the mean ± standard deviation curvature decreasing from 214 ± 74 μm to 67 ± 76 μm (P < 0.05). The iris remained planar in all patients with pigment dispersion syndrome after forced blinking, but the iris concavity recovered to 227 ± 113 μm (P = 0.34) and 238 ± 119 μm (P = 0.19) with the -3.0 and -6.0 diopter lenses, respectively. Pilocarpine-induced miosis caused the iris to assume a planar configuration in all subjects. This study shows that the iris in pigment dispersion syndrome assumes a planar configuration when fixating and that the concavity of the iris surface is not restored by blinking. Accommodation restored the iris concavity, suggesting that the posterior curvature of the iris in pigment dispersion syndrome is induced and probably maintained, at least in part, by accommodation. Copyright © 2011 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

Qualitative evaluation of the iris and ciliary body by ultrasound biomicroscopy in subjects with angle closure.

PubMed

Ku, Judy Y; Nongpiur, Monisha E; Park, Judy; Narayanaswamy, Arun K; Perera, Shamira A; Tun, Tin A; Kumar, Rajesh S; Baskaran, Mani; Aung, Tin

2014-12-01

To qualitatively analyze anterior chamber structures imaged by ultrasound biomicroscopy (UBM) in primary angle-closure patients. Subjects diagnosed as primary angle-closure suspect (PACS), primary angle-closure glaucoma (PACG), and previous acute primary angle closure (APAC) were recruited prospectively along with a group of normal controls. UBM was performed under standardized dark room conditions and qualitative assessment was carried out using a set of reference photographs of standard UBM images to categorize the various anatomic features related to angle configuration. These included overall and basal iris thicknesses, iris convexity, iris angulation, ciliary body size, and ciliary sulcus. A total of 60 PACS, 114 PACG, 41 APAC, and 33 normal controls were included. Patients were predominantly older Chinese females. After controlling the confounding effect of age and sex, eyes with overall thicker irides [medium odds ratio (OR) 3.58, thick OR 2.84] when compared with thin irides have a significantly higher likelihood of having PACS/PACG/APAC versus controls. Thicker basal iris component (medium OR 4.13, thick OR 3.39) also have higher likelihood of having angle closure when compared with thin basal iris thickness. Subjects with basal iris insertion, mild iris angulation, and large ciliary body have a higher OR of having angle closure. In contrast, the presence/absence of a ciliary sulcus did not influence the likelihood of angle closure. Eyes with thicker overall and basal iris thicknesses are more likely to have angle closure than controls. Other features that increase the likelihood of angle closure include basal iris insertion, mild iris angulation, and large ciliary body.

TREATMENT WITH THIDIAZURON IMPROVES OPENING AND VASE LIFE OF IRIS FLOWERS

USDA-ARS?s Scientific Manuscript database

The marketability of Dutch iris (Iris × hollandica) cut flowers is limited by their short display life and frequent failure to open fully. We tested the ability of thidiazuron (TDZ), a phenyl urea compound with cytokinin-like activity, to improve iris flower opening and longevity. A postharvest pu...

An experimental comparison of online object-tracking algorithms

NASA Astrophysics Data System (ADS)

Wang, Qing; Chen, Feng; Xu, Wenli; Yang, Ming-Hsuan

2011-09-01

This paper reviews and evaluates several state-of-the-art online object tracking algorithms. Notwithstanding decades of efforts, object tracking remains a challenging problem due to factors such as illumination, pose, scale, deformation, motion blur, noise, and occlusion. To account for appearance change, most recent tracking algorithms focus on robust object representations and effective state prediction. In this paper, we analyze the components of each tracking method and identify their key roles in dealing with specific challenges, thereby shedding light on how to choose and design algorithms for different situations. We compare state-of-the-art online tracking methods including the IVT,1 VRT,2 FragT,3 BoostT,4 SemiT,5 BeSemiT,6 L1T,7 MILT,8 VTD9 and TLD10 algorithms on numerous challenging sequences, and evaluate them with different performance metrics. The qualitative and quantitative comparative results demonstrate the strength and weakness of these algorithms.

A Survey of Recent Advances in Particle Filters and Remaining Challenges for Multitarget Tracking

PubMed Central

Wang, Xuedong; Sun, Shudong; Corchado, Juan M.

2017-01-01

We review some advances of the particle filtering (PF) algorithm that have been achieved in the last decade in the context of target tracking, with regard to either a single target or multiple targets in the presence of false or missing data. The first part of our review is on remarkable achievements that have been made for the single-target PF from several aspects including importance proposal, computing efficiency, particle degeneracy/impoverishment and constrained/multi-modal systems. The second part of our review is on analyzing the intractable challenges raised within the general multitarget (multi-sensor) tracking due to random target birth and termination, false alarm, misdetection, measurement-to-track (M2T) uncertainty and track uncertainty. The mainstream multitarget PF approaches consist of two main classes, one based on M2T association approaches and the other not such as the finite set statistics-based PF. In either case, significant challenges remain due to unknown tracking scenarios and integrated tracking management. PMID:29168772

2014 Summer Series - Robert Carvalho - Pursuing the Mysteries of the Sun: The IRIS Mission

NASA Image and Video Library

2014-06-19

Pursuing the Mysteries of the Sun: The Interface Region Imaging Spectrograph (IRIS) Mission. Flight controllers from the IRIS mission will present their individual experiences on IRIS from development through the first year of flight. This will begin with a discussion of the unique nature of IRIS's mission and science, and how it fits into NASA's fleet of solar observatories. Next will be a discussion of the critical roles Ames contributed in the mission including spacecraft and flight software development, ground system development, and training for launch. This will be followed by experiences from launch, early operations, ongoing operations, and unusual operations experiences. The presentation will close with IRIS science imagery and questions.

An Improved Iris Recognition Algorithm Based on Hybrid Feature and ELM

NASA Astrophysics Data System (ADS)

Wang, Juan

2018-03-01

The iris image is easily polluted by noise and uneven light. This paper proposed an improved extreme learning machine (ELM) based iris recognition algorithm with hybrid feature. 2D-Gabor filters and GLCM is employed to generate a multi-granularity hybrid feature vector. 2D-Gabor filter and GLCM feature work for capturing low-intermediate frequency and high frequency texture information, respectively. Finally, we utilize extreme learning machine for iris recognition. Experimental results reveal our proposed ELM based multi-granularity iris recognition algorithm (ELM-MGIR) has higher accuracy of 99.86%, and lower EER of 0.12% under the premise of real-time performance. The proposed ELM-MGIR algorithm outperforms other mainstream iris recognition algorithms.

Blinking supervision in a working environment

NASA Astrophysics Data System (ADS)

Morcego, Bernardo; Argilés, Marc; Cabrerizo, Marc; Cardona, Genís; Pérez, Ramon; Pérez-Cabré, Elisabet; Gispets, Joan

2016-02-01

The health of the ocular surface requires blinks of the eye to be frequent in order to provide moisture and to renew the tear film. However, blinking frequency has been shown to decrease in certain conditions such as when subjects are conducting tasks with high cognitive and visual demands. These conditions are becoming more common as people work or spend their leisure time in front of video display terminals. Supervision of blinking frequency in such environments is possible, thanks to the availability of computer-integrated cameras. Therefore, the aim of the present study is to develop an algorithm for the detection of eye blinks and to test it, in a number of videos captured, while subjects are conducting a variety of tasks in front of the computer. The sensitivity of the algorithm for blink detection was found to be of 87.54% (range 30% to 100%), with a mean false-positive rate of 0.19% (range 0% to 1.7%), depending on the illumination conditions during which the image was captured and other computer-user spatial configurations. The current automatic process is based on a partly modified pre-existing eye detection and image processing algorithms and consists of four stages that are aimed at eye detection, eye tracking, iris detection and segmentation, and iris height/width ratio assessment.

Introduction of digital object identifiers (DOI) for seismic networks

NASA Astrophysics Data System (ADS)

Evans, Peter; Strollo, Angelo; Clark, Adam; Ahern, Tim; Newman, Rob; Clinton, John; Pequegnat, Catherine; Pedersen, Helle

2015-04-01

Proper attribution for scientific source data is important in promoting transparency and recognising the role of data providers in science. Data sets such as those produced by seismic networks now need to be citable and permanently locatable for research users. Recently the EIDA and IRIS-DMC communities have worked together on development of methods for generation, maintenance and promotion of persistent identifiers for seismic networks. This resulted in a 2014 Recommendation by the International Federation of Digital Seismograph Networks (FDSN) on the use of Digital Object Identifiers (DOI) for seismic networks. These can be cited equivalently to scientific papers, and tools such as DataCite allow the tracking of citations to these datasets. The GEOFON, IRIS and RESIF data centres have now begun to roll-out of these seismic network DOIs. This has involved working with principal investigators to prepare metadata consistent with the FDSN recommendation, preparation of landing pages, and changes to the web sites to promote DOIs where available. This has involved preparing improved descriptions of the data (metadata) and clarifying how individuals and institutions should best be recognised for their contributions to making the data available. We illustrate this process for a few representative networks. We will be in contact with additional network operators to help them establish DOIs for their networks in future.

Applications of the IRI in Southern Africa

NASA Astrophysics Data System (ADS)

Coetzee, P. J.

2004-01-01

The IRI forms the basis of the Single Site Location Direction Finding networks of the South African Defence Force as well as theNational Intelligence Agency. It is also used in "Path Analysis" applications where the possible transmitter coverage is calculated. Another application of the IRI is in HF frequency predictions, especially for the South African Defence Force involved in peace keeping duties in Africa. The IRI is either used independently or in conjunction with vertical ionosondes. In the latter case the scaled F2 peak parameters (foF2, hmF2) are used as inputs to the IRI. The IRI thus gets "calibrated" to extend the area covered by the ionosonde(s). The IRI has proved to be a very important tool in South Africa and Africa in the fight against crime, drug trafficking, political instability and maintaining the peace in potentially unstable countries.

IRIS Toxicological Review of Benzo[a]pyrene (Interagency ...

EPA Pesticide Factsheets

On August 21, 2013, the draft Toxicological Review of Benzo[a]pyrene and the draft charge to external peer reviewers were released for public review and comment. The Toxicological Review and charge were reviewed internally by EPA and by other federal agencies and White House Offices before public release. Consistent with the May 2009 IRIS assessment development process, all written comments on IRIS assessments submitted by other federal agencies and White House Offices are made publicly available. Accordingly, interagency comments and the interagency science consultation materials provided to other agencies, including interagency review drafts of the IRIS Toxicological Review of Benzo[a]pyrene and the charge to external peer reviewers, are posted on this site. EPA is undertaking an update of the Integrated Risk Information System (IRIS) health assessment for benzo[a]pyrene (BaP). The outcome of this project is an updated Toxicological Review and IRIS Summary for BaP that will be entered into the IRIS database.

Optimal wavelength band clustering for multispectral iris recognition.

PubMed

Gong, Yazhuo; Zhang, David; Shi, Pengfei; Yan, Jingqi

2012-07-01

This work explores the possibility of clustering spectral wavelengths based on the maximum dissimilarity of iris textures. The eventual goal is to determine how many bands of spectral wavelengths will be enough for iris multispectral fusion and to find these bands that will provide higher performance of iris multispectral recognition. A multispectral acquisition system was first designed for imaging the iris at narrow spectral bands in the range of 420 to 940 nm. Next, a set of 60 human iris images that correspond to the right and left eyes of 30 different subjects were acquired for an analysis. Finally, we determined that 3 clusters were enough to represent the 10 feature bands of spectral wavelengths using the agglomerative clustering based on two-dimensional principal component analysis. The experimental results suggest (1) the number, center, and composition of clusters of spectral wavelengths and (2) the higher performance of iris multispectral recognition based on a three wavelengths-bands fusion.

IRIS Assessment Plan for Ammonia and Ammonium Salts Noncancer Oral (Scoping and Problem Formulation Materials)

EPA Science Inventory

In April 2018, EPA released the draft IRIS Assessment Plan for Ammonia and Ammonium Salts Noncancer Oral. An IRIS Assessment Plan (IAP) communicates to the public the plan for assessing each individual chemical and includes summary information on the IRIS Program’s sco...

78 FR 53138 - Notice of Extension of Public Comment Period on the Draft IRIS Carcinogenicity Assessment for...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-08-28

... Extension of Public Comment Period on the Draft IRIS Carcinogenicity Assessment for Ethylene Oxide and Addition of Ethylene Oxide to October IRIS Bimonthly Meeting Agenda AGENCY: Environmental Protection Agency... Ethylene Oxide to October IRIS Bimonthly Meeting Agenda. SUMMARY: EPA is announcing an extension of the...

Cross-sensor iris recognition through kernel learning.

PubMed

Pillai, Jaishanker K; Puertas, Maria; Chellappa, Rama

2014-01-01

Due to the increasing popularity of iris biometrics, new sensors are being developed for acquiring iris images and existing ones are being continuously upgraded. Re-enrolling users every time a new sensor is deployed is expensive and time-consuming, especially in applications with a large number of enrolled users. However, recent studies show that cross-sensor matching, where the test samples are verified using data enrolled with a different sensor, often lead to reduced performance. In this paper, we propose a machine learning technique to mitigate the cross-sensor performance degradation by adapting the iris samples from one sensor to another. We first present a novel optimization framework for learning transformations on iris biometrics. We then utilize this framework for sensor adaptation, by reducing the distance between samples of the same class, and increasing it between samples of different classes, irrespective of the sensors acquiring them. Extensive evaluations on iris data from multiple sensors demonstrate that the proposed method leads to improvement in cross-sensor recognition accuracy. Furthermore, since the proposed technique requires minimal changes to the iris recognition pipeline, it can easily be incorporated into existing iris recognition systems.

Mycobacterial Antigen Driven Activation of CD14++CD16− Monocytes Is a Predictor of Tuberculosis-Associated Immune Reconstitution Inflammatory Syndrome

PubMed Central

Andrade, Bruno B.; Singh, Amrit; Narendran, Gopalan; Schechter, Melissa E.; Nayak, Kaustuv; Subramanian, Sudha; Anbalagan, Selvaraj; Jensen, Stig M. R.; Porter, Brian O.; Antonelli, Lis R.; Wilkinson, Katalin A.; Wilkinson, Robert J.; Meintjes, Graeme; van der Plas, Helen; Follmann, Dean; Barber, Daniel L.; Swaminathan, Soumya; Sher, Alan; Sereti, Irini

2014-01-01

Paradoxical tuberculosis-associated immune reconstitution inflammatory syndrome (TB-IRIS) is an aberrant inflammatory response occurring in a subset of TB-HIV co-infected patients initiating anti-retroviral therapy (ART). Here, we examined monocyte activation by prospectively quantitating pro-inflammatory plasma markers and monocyte subsets in TB-HIV co-infected patients from a South Indian cohort at baseline and following ART initiation at the time of IRIS, or at equivalent time points in non-IRIS controls. Pro-inflammatory biomarkers of innate and myeloid cell activation were increased in plasma of IRIS patients pre-ART and at the time of IRIS; this association was confirmed in a second cohort in South Africa. Increased expression of these markers correlated with elevated antigen load as measured by higher sputum culture grade and shorter duration of anti-TB therapy. Phenotypic analysis revealed the frequency of CD14++CD16− monocytes was an independent predictor of TB-IRIS, and was closely associated with plasma levels of CRP, TNF, IL-6 and tissue factor during IRIS. In addition, production of inflammatory cytokines by monocytes was higher in IRIS patients compared to controls pre-ART. These data point to a major role of mycobacterial antigen load and myeloid cell hyperactivation in the pathogenesis of TB-IRIS, and implicate monocytes and monocyte-derived cytokines as potential targets for TB-IRIS prevention or treatment. PMID:25275318

Double hump sign in indentation gonioscopy is correlated with presence of plateau iris configuration regardless of patent iridotomy.

PubMed

Kiuchi, Yoshiaki; Kanamoto, Takashi; Nakamura, Takao

2009-02-01

A plateau iris is one of the clinical forms of angle closure glaucoma. In patients with a patent iridotomy, the double hump sign detected during indentation gonioscopy has been reported to indicate the existence of a plateau iris configuration. The purpose of this study was to determine whether the double hump sign is correlated with the presence of the plateau iris syndrome regardless of the patency of the iridotomy. Five women and 3 men without a patent iridotomy presented with narrow angles on gonioscopy and a double hump sign on indentation gonioscopy. Ultrasound biomicroscopy (UBM) imaging was performed to determine the etiology of the narrow angle and double hump sign, and to determine the appropriate treatment to prevent the progression of visual field damage. Ten patients with narrow angles and without a double hump sign were also examined by UBM to serve as a control group. All 8 patients who showed double hump sign had a short iris root, which was inserted anterior to the ciliary face, a typical anatomic appearance of a plateau iris. On the other hand, only 1 eye of 10 eyes in control group appeared to have a plateau iris. A double hump sign observed on indentation gonioscopy is strongly correlated with the presence of a plateau iris, and therefore a useful indicator of a plateau iris configuration regardless of the patency of a laser iridotomy. Thus, a plateau iris configuration can be detected without using a UBM in many cases.

Iris reconstruction using autologous iris preserved in cold balanced salt solution for 8 hours in iatrogenic total iridodialysis during cataract surgery: a case report.

PubMed

Bang, Seung Pil; Jun, Jong Hwa

2017-04-04

A large iris defect or extensive iridodialysis can be an intractable cause of visual disturbance, photophobia, glare, monocular diplopia, or cosmetic deformity. The implantation of an artificial iris substitute could be an effective option, but this can cause a reduction in endothelial cell density. We succeeded in the anatomical restoration of iris tissue that was totally dialyzed out of the eye, and was preserved in cold balanced salt solution for 8 h. Engrafted iris tissue was maintained within the aqueous humor. A 71-year-old man was referred to our clinic for management of an iatrogenic total iridodialysis. The totally dialyzed iris tissue was immediately preserved in sterile cold balanced salt solution and packed in a sterile biopsy bottle that was surrounded with ice cubes. Under general anesthesia, a pars plana vitrectomy was performed to remove the remaining lens cortex and vitreous fiber anterior to the equator. A sulcus-positioned intraocular lens (IOL) was repositioned and fixed by ab externo scleral sutures. Preserved iris tissue was inserted and ironed using both iris spatula and ocular viscoelastic devices. Five-point ab interno scleral sutures were made 1.0 mm posterior to the limbus. The engrafted iris was successfully maintained for 6 months and did not undergo any atrophic change or depigmentation, which may be caused by primary implantation failure due to a blocked blood supply.

Potential roles for BMP and Pax genes in the development of iris smooth muscle.

PubMed

Jensen, Abbie M

2005-02-01

The embryonic optic cup generates four types of tissue: neural retina, pigmented epithelium, ciliary epithelium, and iris smooth muscle. Remarkably little attention has focused on the development of the iris smooth muscle since Lewis ([1903] J. Am. Anat. 2:405-416) described its origins from the anterior rim of the optic cup neuroepithelium. As an initial step toward understanding iris smooth muscle development, I first determined the spatial and temporal pattern of the development of the iris smooth muscle in the chick by using the HNK1 antibody, which labels developing iris smooth muscle. HNK1 labeling shows that iris smooth muscle development is correlated in time and space with the development of the ciliary epithelial folds. Second, because neural crest is the only other neural tissue that has been shown to generate smooth muscle (Le Lievre and Le Douarin [1975] J. Embryo. Exp. Morphol. 34:125-154), I sought to determine whether iris smooth muscle development shares similarities with neural crest development. Two members of the BMP superfamily, BMP4 and BMP7, which may regulate neural crest development, are highly expressed by cells at the site of iris smooth muscle generation. Third, because humans and mice that are heterozygous for Pax6 mutations have no irides (Hill et al. [1991] Nature 354:522-525; Hanson et al. [1994] Nat. Genet. 6:168-173), I determined the expression of Pax6. I also examined the expression of Pax3 in the developing anterior optic cup. The developing iris smooth muscle coexpresses Pax6 and Pax3. I suggest that some of the eye defects caused by mutations in Pax6, BMP4, and BMP7 may be due to abnormal iris smooth muscle. Copyright 2004 Wiley-Liss, Inc.

Irigenin sensitizes TRAIL-induced apoptosis via enhancing pro-apoptotic molecules in gastric cancer cells.

PubMed

Xu, Ying; Gao, Cheng-Cheng; Pan, Zhen-Guo; Zhou, Chuan-Wen

2018-02-12

Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) holds promising value for cancer therapy due to its capacity to induce apoptosis in cancer cells. Nevertheless, TRAIL therapy is greatly hampered by its resistance. Irigenin (Iri), isoflavonoids, can be isolated from the rhizome of Belamcanda chinensis, and has been shown anti-cancer properties. In this study, we explored if Iri could enhance TRAIL-regulated apoptosis in TRAIL resistant gastric cancer cells. Iri significantly potentiated TRAIL-triggered cytotoxicity. Iri alone and TRAIL alone showed no effective role in apoptosis induction, whereas combined treatment with Iri and TRAIL markedly induced apoptosis in cancer cells, as evidenced by the up-regulation of cleaved Caspase-8/-9/-3 and PARP. Additionally, the sensitization to TRAIL was along with the enhancement of pro-apoptotic proteins, including FAS-associated protein with death domain (FADD), death receptor 5 (DR5) and Bax. And suppressing FADD, DR5 and Bax by si RNA significantly reduced the apoptosis and enhanced the cell viability induced by the co-application of Iri and TRAIL. Moreover, the sensitization to TRAIL was accompanied by the decrease of Cellular-FLICE inhibitory protein (c-FLIP), Bcl-2 and Survivin. Additionally, Iri could sensitize TRAIL to produce reactive oxygen species (ROS). Pre-treatment of N-acetyl-cysteine (NAC), ROS scavenger, attenuated Iri plus TRAIL-induced apoptosis and improved cell viability. Finally, combination of Iri and TRAIL inhibited tumor growth in the xenograft model. Collectively, our present study gave new insights into the effects of Iri on potentiating TRAIL-sensitivity, and suggested that Iri could be a potential candidate for sensitizer of TRAIL-resistant cancer cell treatment. Copyright © 2018. Published by Elsevier Inc.

Real-time image restoration for iris recognition systems.

PubMed

Kang, Byung Jun; Park, Kang Ryoung

2007-12-01

In the field of biometrics, it has been reported that iris recognition techniques have shown high levels of accuracy because unique patterns of the human iris, which has very many degrees of freedom, are used. However, because conventional iris cameras have small depth-of-field (DOF) areas, input iris images can easily be blurred, which can lead to lower recognition performance, since iris patterns are transformed by the blurring caused by optical defocusing. To overcome these problems, an autofocusing camera can be used. However, this inevitably increases the cost, size, and complexity of the system. Therefore, we propose a new real-time iris image-restoration method, which can increase the camera's DOF without requiring any additional hardware. This paper presents five novelties as compared to previous works: 1) by excluding eyelash and eyelid regions, it is possible to obtain more accurate focus scores from input iris images; 2) the parameter of the point spread function (PSF) can be estimated in terms of camera optics and measured focus scores; therefore, parameter estimation is more accurate than it has been in previous research; 3) because the PSF parameter can be obtained by using a predetermined equation, iris image restoration can be done in real-time; 4) by using a constrained least square (CLS) restoration filter that considers noise, performance can be greatly enhanced; and 5) restoration accuracy can also be enhanced by estimating the weight value of the noise-regularization term of the CLS filter according to the amount of image blurring. Experimental results showed that iris recognition errors when using the proposed restoration method were greatly reduced as compared to those results achieved without restoration or those achieved using previous iris-restoration methods.

Paradoxical Tuberculosis Immune Reconstitution Inflammatory Syndrome (TB-IRIS) in HIV Patients with Culture Confirmed Pulmonary Tuberculosis in India and the Potential Role of IL-6 in Prediction

PubMed Central

Porter, Brian O.; Chandrasekhar, Chockalingam; Venkatesan, Perumal; Menon, Pradeep A.; Subramanian, Sudha; Anbalagan, Selvaraj; Bhavani, Kannabiran P.; Sekar, Sathiyavelu; Padmapriyadarshini, Chandrasekaran; Kumar, Satagopan; Ravichandran, Narayanan; Raja, Krishnaraj; Bhanu, Kesavamurthy; Mahilmaran, Ayyamperumal; Sekar, Lakshmanan; Sher, Alan; Sereti, Irini; Swaminathan, Soumya

2013-01-01

Background The incidence, manifestations, outcome and clinical predictors of paradoxical TB-IRIS in patients with HIV and culture confirmed pulmonary tuberculosis (PTB) in India have not been studied prospectively. Methods HIV+ patients with culture confirmed PTB started on anti-tuberculosis therapy (ATT) were followed prospectively after anti-retroviral therapy (ART) initiation. Established criteria for IRIS diagnosis were used including decline in plasma HIV RNA at IRIS event. Pre-ART plasma levels of interleukin (IL)-6 and C-reactive protein (CRP) were measured. Univariate and multivariate logistic regression models were used to evaluate associations between baseline variables and IRIS. Results Of 57 patients enrolled, 48 had complete follow up data. Median ATT-ART interval was 28 days (interquartile range, IQR 14–47). IRIS events occurred in 26 patients (54.2%) at a median of 11 days (IQR: 7–16) after ART initiation. Corticosteroids were required for treatment of most IRIS events that resolved within a median of 13 days (IQR: 9–23). Two patients died due to CNS TB-IRIS. Lower CD4+ T-cell counts, higher plasma HIV RNA levels, lower CD4/CD8 ratio, lower hemoglobin, shorter ATT to ART interval, extra-pulmonary or miliary TB and higher plasma IL-6 and CRP levels at baseline were associated with paradoxical TB-IRIS in the univariate analysis. Shorter ATT to ART interval, lower hemoglobin and higher IL-6 and CRP levels remained significant in the multivariate analysis. Conclusion Paradoxical TB–IRIS frequently complicates HIV-TB therapy in India. IL-6 and CRP may assist in predicting IRIS events and serve as potential targets for immune interventions. PMID:23691062

Interleukin-1 receptor antagonist, a biomarker of response to anti-TB treatment in HIV/TB co-infected patients.

PubMed

Nouhin, Janin; Pean, Polidy; Madec, Yoann; Chevalier, Mathieu F; Didier, Celine; Borand, Laurence; Blanc, François-Xavier; Scott-Algara, Daniel; Laureillard, Didier; Weiss, Laurence

2017-05-01

Despite the high frequency of tuberculosis-associated immune reconstitution inflammatory syndrome (TB-IRIS) in human immunodeficiency virus (HIV)/TB co-infected patients, no diagnostic test is available. Here, we investigated whether monocyte/macrophage activation markers can predict TB-IRIS occurrence and if they are modulated by anti-TB treatment. Frozen plasma was obtained from 127 HIV/TB co-infected adults naïve for antiretroviral therapy, enrolled in the CAMELIA trial, 36 of whom developed TB-IRIS. Concentrations of IL-1Ra, sCD14, and sCD163 were measured at anti-TB treatment onset (baseline), after 8 weeks of anti-TB treatment and at TB-IRIS time. At baseline, IL-1Ra and sCD14 concentrations were similar in TB-IRIS and non-IRIS patients. sCD163 concentrations, although significantly higher in TB-IRIS patients, did not remain associated with TB-IRIS occurrence in multivariate analysis. At the time of TB-IRIS, patients displayed higher concentrations of IL-1Ra (p = 0.002) and sCD14 (p < 0.001). The most striking result was the significant decrease in IL-1Ra after 8 weeks of anti-TB treatment (median reduction: -63% (p < 0.0001)). None of the biomarkers tested was associated with TB-IRIS occurrence. However, repeated measurement of IL-1Ra could help for the diagnosis of TB-IRIS. The substantial reduction of IL-1Ra under treatment suggests that IL-1Ra could be a surrogate biomarker of anti-TB treatment response in HIV-infected patients. Copyright © 2017 The British Infection Association. Published by Elsevier Ltd. All rights reserved.

Assessment of IRI-2012, NeQuick-2 and IRI-Plas 2015 models with observed equatorial ionization anomaly in Africa during 2009 sudden stratospheric warming event

NASA Astrophysics Data System (ADS)

Bolaji, O. S.; Oyeyemi, E. O.; Adewale, A. O.; Wu, Q.; Okoh, D.; Doherty, P. H.; Kaka, R. O.; Abbas, M.; Owolabi, C.; Jidele, P. A.

2017-11-01

In Africa, we assessed the performance of all the three options of International Reference Ionosphere 2012, IRI-2012 (i.e. IRI-2001, IRI-2001COR and IRI-NeQuick), NeQuick-2 and IRI-Plas 2015 models prior to and during 2009 sudden stratospheric warming (SSW) event to predict equatorial ionization anomaly (EIA) crest locations and their magnitudes using total electron content (TEC) from experimental records of Global Positioning System (GPS). We confirmed that the IRI-Plas 2015 that appeared as the best compared to all of the models as regard prediction of the EIA crest locations in the northern hemisphere of Africa is due to discontinuities in the GPS data between ∼8° N and 22° N. As regard the predictions of EIA crest magnitudes and the location of EIA crests in the southern hemisphere of Africa, they are not present in all the models. The NeQuick-2 model does not have the capability to predict either the EIA crest location in the northern or southern hemisphere. The SSW effect on the low latitude was able to modify a single EIA crest to pre-noon and post noon EIA crests in the northern hemisphere during the SSW peak phase and significantly reduced the GPS TEC magnitudes over the hemispheres as well. These SSW effects and delays of plasma transportation to higher latitudes in GPS TEC were absent in all the models. For future improvements of IRI-2012, NeQuick-2 and IRI-Plas 2015 models, SSW conditions should be included in order to characterize the effect of lower atmosphere on the ionosphere. The EIA trough modeling is only present in IRI-2001COR and IRI-2001NeQuick options. In the middle latitude, all the model could not predict the location of highest TEC magnitudes found at RBAY (Richardsbay, South Africa).

Contribution of Different Anatomical and Physiologic Factors to Iris Contour and Anterior Chamber Angle Changes During Pupil Dilation: Theoretical Analysis

PubMed Central

Jouzdani, Sara; Amini, Rouzbeh; Barocas, Victor H.

2013-01-01

Purpose. To investigate the contribution of three anatomical and physiologic factors (dilator thickness, dynamic pupillary block, and iris compressibility) to changes in iris configuration and anterior chamber angle during pupil dilation. Methods. A mathematical model of the anterior segment based on the average values of ocular dimensions was developed to simulate pupil dilation. To change the pupil diameter from 3.0 to 5.4 mm in 10 seconds, active dilator contraction was applied by imposing stress in the dilator region. Three sets of parameters were varied in the simulations: (1) a thin (4 μm, 1% of full thickness) versus a thick dilator (covering the full thickness iris) to quantify the effects of dilator anatomy, (2) in the presence (+PB) versus absence of pupillary block (−PB) to quantify the effect of dynamic motion of aqueous humor from the posterior to the anterior chamber, and (3) a compressible versus an incompressible iris to quantify the effects of iris volume change. Changes in the apparent iris–lens contact and angle open distance (AOD500) were calculated for each case. Results. The thin case predicted a significant increase (average 700%) in iris curvature compared with the thick case (average 70%), showing that the anatomy of dilator plays an important role in iris deformation during dilation. In the presence of pupillary block (+PB), AOD500 decreased 25% and 36% for the compressible and incompressible iris, respectively. Conclusions. Iris bowing during dilation was driven primarily by posterior location of the dilator muscle and by dynamic pupillary block, but the effect of pupillary block was not as large as that of the dilator anatomy according to the quantified values of AOD500. Incompressibility of the iris, in contrast, had a relatively small effect on iris curvature but a large effect on AOD500; thus, we conclude that all three effects are important. PMID:23482467

Establishing Age-Adjusted Reference Ranges for Iris-Related Parameters in Open Angle Eyes with Anterior Segment Optical Coherence Tomography

PubMed Central

Peterson, Jeffrey R.; Blieden, Lauren S.; Chuang, Alice Z.; Baker, Laura A.; Rigi, Mohammed; Feldman, Robert M.; Bell, Nicholas P.

2016-01-01

Purpose Define criteria for iris-related parameters in an adult open angle population as measured with swept source Fourier domain anterior segment optical coherence tomography (ASOCT). Methods Ninety-eight eyes of 98 participants with open angles were included and stratified into 5 age groups (18–35, 36–45, 46–55, 56–65, and 66–79 years). ASOCT scans with 3D mode angle analysis were taken with the CASIA SS-1000 (Tomey Corporation, Nagoya, Japan) and analyzed using the Anterior Chamber Analysis and Interpretation software. Anterior iris surface length (AISL), length of scleral spur landmark (SSL) to pupillary margin (SSL-to-PM), iris contour ratio (ICR = AISL/SSL-to-PM), pupil radius, radius of iris centroid (RICe), and iris volume were measured. Outcome variables were summarized for all eyes and age groups, and mean values among age groups were compared using one-way analysis of variance. Stepwise regression analysis was used to investigate demographic and ocular characteristic factors that affected each iris-related parameter. Results Mean (±SD) values were 2.24 mm (±0.46), 4.06 mm (±0.27), 3.65 mm (±0.48), 4.16 mm (±0.47), 1.14 (±0.04), 1.51 mm2 (±0.23), and 38.42 μL (±4.91) for pupillary radius, RICe, SSL-to-PM, AISL, ICR, iris cross-sectional area, and iris volume, respectively. Both pupillary radius (P = 0.002) and RICe (P = 0.027) decreased with age, while SSL-to-PM (P = 0.002) and AISL increased with age (P = 0.001). ICR (P = 0.54) and iris volume (P = 0.49) were not affected by age. Conclusion This study establishes reference values for iris-related parameters in an adult open angle population, which will be useful for future studies examining the role of iris changes in pathologic states. PMID:26815917

Establishing Age-Adjusted Reference Ranges for Iris-Related Parameters in Open Angle Eyes with Anterior Segment Optical Coherence Tomography.

PubMed

Peterson, Jeffrey R; Blieden, Lauren S; Chuang, Alice Z; Baker, Laura A; Rigi, Mohammed; Feldman, Robert M; Bell, Nicholas P

2016-01-01

Define criteria for iris-related parameters in an adult open angle population as measured with swept source Fourier domain anterior segment optical coherence tomography (ASOCT). Ninety-eight eyes of 98 participants with open angles were included and stratified into 5 age groups (18-35, 36-45, 46-55, 56-65, and 66-79 years). ASOCT scans with 3D mode angle analysis were taken with the CASIA SS-1000 (Tomey Corporation, Nagoya, Japan) and analyzed using the Anterior Chamber Analysis and Interpretation software. Anterior iris surface length (AISL), length of scleral spur landmark (SSL) to pupillary margin (SSL-to-PM), iris contour ratio (ICR = AISL/SSL-to-PM), pupil radius, radius of iris centroid (RICe), and iris volume were measured. Outcome variables were summarized for all eyes and age groups, and mean values among age groups were compared using one-way analysis of variance. Stepwise regression analysis was used to investigate demographic and ocular characteristic factors that affected each iris-related parameter. Mean (±SD) values were 2.24 mm (±0.46), 4.06 mm (±0.27), 3.65 mm (±0.48), 4.16 mm (±0.47), 1.14 (±0.04), 1.51 mm2 (±0.23), and 38.42 μL (±4.91) for pupillary radius, RICe, SSL-to-PM, AISL, ICR, iris cross-sectional area, and iris volume, respectively. Both pupillary radius (P = 0.002) and RICe (P = 0.027) decreased with age, while SSL-to-PM (P = 0.002) and AISL increased with age (P = 0.001). ICR (P = 0.54) and iris volume (P = 0.49) were not affected by age. This study establishes reference values for iris-related parameters in an adult open angle population, which will be useful for future studies examining the role of iris changes in pathologic states.

Clinicopathological correlates in HIV seropositive tuberculosis cases presenting with jaundice after initiating antiretroviral therapy with a structured review of the literature

PubMed Central

2012-01-01

Background The development of jaundice after initiation of HAART in HIV-TB co-infected patients is a challenging presentation in resource constrained settings, and is often attributed to drug induced liver injury (DILI).Some investigators have described hepatic tuberculosis Immune Reconstitution Inflammatory Syndrome (TB-IRIS) as a cause of liver disease in patients initiating HAART, which could also cause jaundice. Case presentations We report the clinical and histopathological features of five HIV-TB co-infected patients presenting with a syndrome of jaundice, tender hepatomegaly, bile canalicular enzyme rise and return of constitutional symptoms within 8 weeks of initiation of highly active antiretroviral therapy (HAART) for advanced HIV infection at a rural clinic in KwaZulu Natal, South Africa. All five patients had been diagnosed with tuberculosis infection prior to HAART initiation and were on antituberculous medication at time of developing jaundice. There was evidence of multiple aetiologies of liver injury in all patients. However, based on clinical course and pathological findings, predominant hepatic injury was thought to be drug induced in one case and hepatic tuberculosis associated immune reconstitution inflammatory syndrome (TB-IRIS) in the other four. In these later 4 patients, liver biopsy findings included necrotising and non-necrotising granulomatous inflammation in the lobules and portal tracts. The granulomas demonstrated – in addition to epithelioid histiocytes and Langhans giant cells – neutrophils, plasma cells and large numbers of lymphocytes, which are not features of a conventional untreated tuberculous response. Conclusion In this high TB prevalent, low resource setting, TB-IRIS may be an important cause of jaundice post-HAART initiation. Clinicopathological correlation is essential for optimal diagnosis. Further multi-organ based histopathological studies in the context of immune reconstitution would be useful to clinicians in low resource settings dealing with this challenging presentation. PMID:23061403

Spatula scaffold: An iris-sparing technique for lensectomy.

PubMed

Narang, Priya; Agarwal, Amar

2017-12-01

Lensectomy with vitrectomy is often performed for crystalline lenticular subluxation. We report a new technique and a practical approach that involves the placement of a spatula beneath the iris tissue that facilitates retroiridial removal of subluxated lens and acts as a scaffold by protecting the iris tissue from being accidentally trapped into the vitrectomy cutter port. Our technique facilitates management of the lens and vitreous without any trauma to the iris and secondarily obviates the need to perform an iris repair procedure that may arise due to iatrogenic reasons.

IRIS Toxicological Review of Ammonia (External Review Draft ...

EPA Pesticide Factsheets

EPA is conducting a peer review of the scientific basis supporting the human health hazard and dose-response assessment of ammonia that will appear in the Integrated Risk Information System (IRIS) database. EPA is undertaking an Integrated Risk Information System (IRIS) health assessment for ammonia. IRIS is an EPA database containing Agency scientific positions on potential adverse human health effects that may result from chronic (or lifetime) exposure to chemicals in the environment. IRIS contains chemical-specific summaries of qualitative and quantitative health information in support of two steps of the risk assessment paradigm, i.e., hazard identification and dose-response evaluation. IRIS assessments are used in combination with specific situational exposure assessment information to evaluate potential public health risk associated with environmental contaminants.

On-instrument wavefront sensor design for the TMT infrared imaging spectrograph (IRIS) update

NASA Astrophysics Data System (ADS)

Dunn, Jennifer; Reshetov, Vladimir; Atwood, Jenny; Pazder, John; Wooff, Bob; Loop, David; Saddlemyer, Leslie; Moore, Anna M.; Larkin, James E.

2014-08-01

The first light instrument on the Thirty Meter Telescope (TMT) project will be the InfraRed Imaging Spectrograph (IRIS). IRIS will be mounted on a bottom port of the facility AO instrument NFIRAOS. IRIS will report guiding information to the NFIRAOS through the On-Instrument Wavefront Sensor (OIWFS) that is part of IRIS. This will be in a self-contained compartment of IRIS and will provide three deployable wavefront sensor probe arms. This entire unit will be rotated to provide field de-rotation. Currently in our preliminary design stage our efforts have included: prototyping of the probe arm to determine the accuracy of this critical component, handling cart design and reviewing different types of glass for the atmospheric dispersion.

IRIS Toxicological Review of 2-Hexanone (Interagency ...

EPA Pesticide Factsheets

On September 25, 2009, the IRIS Summary and Toxicological Review of 2-hexanone was finalized and loaded onto the IRIS database. The Toxicological Review of 2-hexanone was reviewed internally by EPA, by other federal agencies and White House Offices, by expert external peer reviewers, and by the public. In the new IRIS process, introduced by the EPA Administrator, all written comments on IRIS assessments submitted by other federal agencies and White House Offices will be made publicly available. Accordingly, interagency comments and the interagency draft of the 2-hexanone IRIS assessment are posted on this site. The draft Toxicological Review of 2-hexanone provides scientific support and rationale for the hazard identification and dose-response assessment pertaining to chronic exposure to 2-hexanone.

IRIS Toxicological Review of n-Butanol (External Review Draft ...

EPA Pesticide Factsheets

EPA is conducting a peer review of the scientific basis supporting the human health hazard and dose-response assessment of n-butanol that will appear in the Integrated Risk Information System (IRIS) database. EPA is undertaking an Integrated Risk Information System (IRIS) health assessment for n-butanol. IRIS is an EPA database containing Agency scientific positions on potential adverse human health effects that may result from chronic (or lifetime) exposure to chemicals in the environment. IRIS contains chemical-specific summaries of qualitative and quantitative health information in support of two steps of the risk assessment paradigm, i.e., hazard identification and dose-response evaluation. IRIS assessments are used in combination with specific situational exposure assessment information to evaluate potential public health risk associated with environmental contaminants.

IRIS Toxicological Review of 1,2,3-trichloropropane ...

EPA Pesticide Factsheets

On September 30, 2009, the IRIS Summary and Toxicological Review of 1,2,3-trichloropropane (TCP) was finalized and loaded onto the IRIS database. The Toxicological Review of TCP was reviewed internally by EPA, by other federal agencies and White House Offices, by expert external peer reviewers, and by the public. In the new IRIS process, introduced by the EPA Administrator, all written comments on IRIS assessments submitted by other federal agencies and White House Offices will be made publicly available. Accordingly, interagency comments and the interagency draft of the TCP IRIS assessment are posted on this site. This Tox Review provides scientific support and rationale for the hazard and dose-response assessment pertaining to chronic exposure to 1,2,3-trichloropropane.

Iris unwrapping using the Bresenham circle algorithm for real-time iris recognition

NASA Astrophysics Data System (ADS)

Carothers, Matthew T.; Ngo, Hau T.; Rakvic, Ryan N.; Broussard, Randy P.

2015-02-01

An efficient parallel architecture design for the iris unwrapping process in a real-time iris recognition system using the Bresenham Circle Algorithm is presented in this paper. Based on the characteristics of the model parameters this algorithm was chosen over the widely used polar conversion technique as the iris unwrapping model. The architecture design is parallelized to increase the throughput of the system and is suitable for processing an inputted image size of 320 × 240 pixels in real-time using Field Programmable Gate Array (FPGA) technology. Quartus software is used to implement, verify, and analyze the design's performance using the VHSIC Hardware Description Language. The system's predicted processing time is faster than the modern iris unwrapping technique used today∗.

Medical information security in the era of artificial intelligence.

PubMed

Wang, Yufeng; Wang, Liwei; Xue, Chang-Ao

2018-06-01

In recent years, biometric technologies, such as iris, facial, and finger vein recognition, have reached consumers and are being increasingly applied. However, it remains unknown whether these highly specific biometric technologies are as safe as declared by their manufacturers. As three-dimensional (3D) reconstruction based on medical imaging and 3D printing are being developed, these biometric technologies may face severe challenges. Copyright © 2018 Elsevier Ltd. All rights reserved.

Mitigation of autophagy ameliorates hepatocellular damage following ischemia-reperfusion injury in murine steatotic liver

PubMed Central

Kolachala, Vasantha L.; Jiang, Rong; Abramowsky, Carlos; Shenoi, Asha; Kosters, Astrid; Pavuluri, Haritha; Anania, Frank; Kirk, Allan D.

2014-01-01

Ischemia-reperfusion injury (IRI) is a common clinical consequence of hepatic surgery, cardiogenic shock, and liver transplantation. A steatotic liver is particularly vulnerable to IRI, responding with extensive hepatocellular injury. Autophagy, a lysosomal pathway balancing cell survival and cell death, is engaged in IRI, although its role in IRI of a steatotic liver is unclear. The role of autophagy was investigated in high-fat diet (HFD)-fed mice exposed to IRI in vivo and in steatotic hepatocytes exposed to hypoxic IRI (HIRI) in vitro. Two inhibitors of autophagy, 3-methyladenine and bafilomycin A1, protected the steatotic hepatocytes from HIRI. Exendin 4 (Ex4), a glucagon-like peptide 1 analog, also led to suppression of autophagy, as evidenced by decreased autophagy-associated proteins [microtubule-associated protein 1A/1B-light chain 3 (LC3) II, p62, high-mobility group protein B1, beclin-1, and autophagy-related protein 7], reduced hepatocellular damage, and improved mitochondrial structure and function in HFD-fed mice exposed to IRI. Decreased autophagy was further demonstrated by reversal of a punctate pattern of LC3 and decreased autophagic flux after IRI in HFD-fed mice. Under the same conditions, the effects of Ex4 were reversed by the competitive antagonist exendin 9-39. The present study suggests that, in IRI of hepatic steatosis, treatment of hepatocytes with Ex4 mitigates autophagy, ameliorates hepatocellular injury, and preserves mitochondrial integrity. These data suggest that therapies targeting autophagy, by Ex4 treatment in particular, may ameliorate the effects of IRI in highly prevalent steatotic liver. PMID:25258410

Iris alterations after DSAEK.

PubMed

Del Hierro Zarzuelo, A; Boto de Los Bueis, A

2016-09-01

To evaluate a series of case that developed iris changes after performing Descemet's stripping automated endothelial keratoplasty (DSAEK). Retrospective study of eyes that developed iris abnormalities, such as pupil ovalisation, iris atrophy, iridocorneal synechiae, mydriatic pupil, and pigmentary changes after performing DSAEK in a tertiary hospital. In a series of the first 32 DSAEK procedures performed, new single or mixed iris alterations were observed in 12 eyes (37.5%). Iris-corneal synechiae were observed in 7 eyes, corectopias in 9 eyes, iris atrophy in 3 cases, and one case developed an areflexic mydriatic pupil. Long-term pigment dispersion at the edge of the lenticule was observed in 12 eyes. The alterations occurred after three months from the surgery. In the evaluation of the associated factors, malignant glaucoma had occurred in 1 case, 2 eyes had required a second surgery, one case by re-DSAEK, and the other one by removing the intraocular lens due to lens opacification. Two cases had a shallow anterior chamber. No relationship was found between the thickness of the peripheral lenticule and the presence of synechiae. Iris changes regarding DSAEK are possible. A discussion is presented on the relationship between increased intraocular pressure due to air in anterior chamber and its relationship with ischaemia and secondary alterations in the iris. Copyright © 2016 Sociedad Española de Oftalmología. Published by Elsevier España, S.L.U. All rights reserved.

Gaze Estimation for Off-Angle Iris Recognition Based on the Biometric Eye Model

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

Karakaya, Mahmut; Barstow, Del R; Santos-Villalobos, Hector J

Iris recognition is among the highest accuracy biometrics. However, its accuracy relies on controlled high quality capture data and is negatively affected by several factors such as angle, occlusion, and dilation. Non-ideal iris recognition is a new research focus in biometrics. In this paper, we present a gaze estimation method designed for use in an off-angle iris recognition framework based on the ANONYMIZED biometric eye model. Gaze estimation is an important prerequisite step to correct an off-angle iris images. To achieve the accurate frontal reconstruction of an off-angle iris image, we first need to estimate the eye gaze direction frommore » elliptical features of an iris image. Typically additional information such as well-controlled light sources, head mounted equipment, and multiple cameras are not available. Our approach utilizes only the iris and pupil boundary segmentation allowing it to be applicable to all iris capture hardware. We compare the boundaries with a look-up-table generated by using our biologically inspired biometric eye model and find the closest feature point in the look-up-table to estimate the gaze. Based on the results from real images, the proposed method shows effectiveness in gaze estimation accuracy for our biometric eye model with an average error of approximately 3.5 degrees over a 50 degree range.« less

The International Reference Ionosphere 2012 - a model of international collaboration

NASA Astrophysics Data System (ADS)

Bilitza, Dieter; Altadill, David; Zhang, Yongliang; Mertens, Chris; Truhlik, Vladimir; Richards, Phil; McKinnell, Lee-Anne; Reinisch, Bodo

2014-02-01

The International Reference Ionosphere (IRI) project was established jointly by the Committee on Space Research (COSPAR) and the International Union of Radio Science (URSI) in the late sixties with the goal to develop an international standard for the specification of plasma parameters in the Earth's ionosphere. COSPAR needed such a specification for the evaluation of environmental effects on spacecraft and experiments in space, and URSI for radiowave propagation studies and applications. At the request of COSPAR and URSI, IRI was developed as a data-based model to avoid the uncertainty of theory-based models which are only as good as the evolving theoretical understanding. Being based on most of the available and reliable observations of the ionospheric plasma from the ground and from space, IRI describes monthly averages of electron density, electron temperature, ion temperature, ion composition, and several additional parameters in the altitude range from 60 km to 2000 km. A working group of about 50 international ionospheric experts is in charge of developing and improving the IRI model. Over time as new data became available and new modeling techniques emerged, steadily improved editions of the IRI model have been published. This paper gives a brief history of the IRI project and describes the latest version of the model, IRI-2012. It also briefly discusses efforts to develop a real-time IRI model. The IRI homepage is at http://IRImodel.org.

IRIS: Supporting & Managing the Research Life-Cycle

ERIC Educational Resources Information Center

Bollini, Andrea; Mennielli, Michele; Mornati, Susanna; Palmer, David T.

2016-01-01

IRIS is a new Current Research Information System (CRIS) developed by Cineca to upgrade and replace two previous solutions that have been used by Italian universities in the last 10 years. At the end of 2015, sixty-three Italian institutions are using IRIS. One of the main components of IRIS is DSpace-CRIS, an open source solution that can also be…

[The automatic iris map overlap technology in computer-aided iridiagnosis].

PubMed

He, Jia-feng; Ye, Hu-nian; Ye, Miao-yuan

2002-11-01

In the paper, iridology and computer-aided iridiagnosis technologies are briefly introduced and the extraction method of the collarette contour is then investigated. The iris map can be overlapped on the original iris image based on collarette contour extraction. The research on collarette contour extraction and iris map overlap is of great importance to computer-aided iridiagnosis technologies.

IRIS Toxicological Review of Ammonia (Interagency Science ...

EPA Pesticide Factsheets

On June 1, 2012, the draft Toxicological Review of Ammonia and the draft charge to external peer reviewers were released for external peer review and public comment. The Toxicological Review and charge were reviewed internally by EPA and by other federal agencies and White House Offices before public release. Consistent with the May 2009 IRIS assessment development process, all written comments on IRIS assessments submitted by other federal agencies and White House Offices are made publicly available. Accordingly, interagency comments and the interagency science consultation materials provided to other agencies, including interagency review drafts of the IRIS Toxicological Review of Ammonia and the charge to external peer reviewers, are posted on this site. EPA is undertaking an Integrated Risk Information System (IRIS) health assessment for ammonia. IRIS is an EPA database containing Agency scientific positions on potential adverse human health effects that may result from chronic (or lifetime) exposure to chemicals in the environment. IRIS contains chemical-specific summaries of qualitative and quantitative health information in support of two steps of the risk assessment paradigm, i.e., hazard identification and dose-response evaluation. IRIS assessments are used in combination with specific situational exposure assessment information to evaluate potential public health risk associated with environmental contaminants.

IRIS Toxicological Review of n-Butanol (Interagency Science ...

EPA Pesticide Factsheets

On September 8, 2011, the Toxicological Review of n-Butanol (External Review Draft) was released for external peer review and public comment. The Toxicological Review and charge were reviewed internally by EPA and by other federal agencies and White House Offices before public release. In the new IRIS process, introduced by the EPA Administrator, all written comments on IRIS assessments submitted by other federal agencies and White House Offices will be made publicly available. Accordingly, interagency comments with EPA's response and the interagency science consultation draft of the IRIS Toxicological Review of n-Butanol and the charge to external peer reviewers are posted on this site. EPA is undertaking an Integrated Risk Information System (IRIS) health assessment for n-butanol. IRIS is an EPA database containing Agency scientific positions on potential adverse human health effects that may result from chronic (or lifetime) exposure to chemicals in the environment. IRIS contains chemical-specific summaries of qualitative and quantitative health information in support of two steps of the risk assessment paradigm, i.e., hazard identification and dose-response evaluation. IRIS assessments are used in combination with specific situational exposure assessment information to evaluate potential public health risk associated with environmental contaminants.

Fluorescein angiography of the iris in anterior segment pigment dispersal syndrome.

PubMed Central

Gillies, W E; Tangas, C

1986-01-01

The results are presented of fluorescein angiography of the iris in 11 patients with anterior segment pigment dispersal syndrome. These show a general hypovascularity of the iris with fine neovascularisation at the pupil margin and the peripupillary area. Hypoplasia of the iris stroma was also present in many cases. When the condition was virtually unilateral, the vascular changes were present though less marked in the relatively unaffected eye. It is postulated that the anterior segment pigment dispersal syndrome is secondary to a congenital mesodermal deficiency of the iris stroma with hypovascularity of the iris, which forms a poor support tissue for the pigment epithelium of the iris, resulting in shedding of pigment granules particularly in the region of the attachment of the dilator muscle to the pigment epithelium. The condition may be hereditary. Because of the hypovascularity the mesodermal hypoplasia may be progressive, but pigment release may diminish in later life with treatment, with consequent diminution of pupil activity. Images PMID:2421760

Feature and Score Fusion Based Multiple Classifier Selection for Iris Recognition

PubMed Central

Islam, Md. Rabiul

2014-01-01

The aim of this work is to propose a new feature and score fusion based iris recognition approach where voting method on Multiple Classifier Selection technique has been applied. Four Discrete Hidden Markov Model classifiers output, that is, left iris based unimodal system, right iris based unimodal system, left-right iris feature fusion based multimodal system, and left-right iris likelihood ratio score fusion based multimodal system, is combined using voting method to achieve the final recognition result. CASIA-IrisV4 database has been used to measure the performance of the proposed system with various dimensions. Experimental results show the versatility of the proposed system of four different classifiers with various dimensions. Finally, recognition accuracy of the proposed system has been compared with existing N hamming distance score fusion approach proposed by Ma et al., log-likelihood ratio score fusion approach proposed by Schmid et al., and single level feature fusion approach proposed by Hollingsworth et al. PMID:25114676

IRIS Toxicological Review of Hexahydro-1,3,5-Trinitro-1,3,5 ...

EPA Pesticide Factsheets

On March 10, 2016, the public comment draft Toxicological Review of Hexahydro-1,3,5-trinitro-1,3,5-triazine and the draft charge to external peer reviewers were released for public review and comment. The Toxicological Review and charge were reviewed internally by EPA and by other federal agencies and White House Offices before public release. Consistent with the May 2009 IRIS assessment development process, all written comments on IRIS assessments submitted by other federal agencies and White House Offices are made publicly available. Accordingly, interagency comments and the interagency science consultation materials provided to other agencies, including interagency review drafts of the IRIS Toxicological Review of Hexahydro-1,3,5-trinitro-1,3,5-triazine and the charge to external peer reviewers, are posted on this site. EPA is undertaking an update of the Integrated Risk Information System (IRIS) health assessment for RDX. The outcome of this project is an updated Toxicological Review and IRIS Summary for RDX that will be entered into the IRIS database.

A hyperspectral imaging system for the evaluation of the human iris spectral reflectance

NASA Astrophysics Data System (ADS)

Di Cecilia, Luca; Marazzi, Francesco; Rovati, Luigi

2017-02-01

According to previous studies, the measurement of the human iris pigmentation can be exploited to detect certain eye pathological conditions in their early stage. In this paper, we propose an instrument and a method to perform hyperspectral quantitative measurements of the iris spectral reflectance. The system is based on a simple imaging setup, which includes a monochrome camera mounted on a standard ophthalmic microscope movement controller, a monochromator, and a flashing LED-based slit lamp. To assure quantitative measurements, the system is properly calibrated against a NIST reflectance standard. Iris reflectance images can be obtained in the spectral range 495-795 nm with a resolution of 25 nm. Each image consists of 1280 x 1024 pixels having a spatial resolution of 18 μm. Reflectance spectra can be calculated both from discrete areas of the iris and as the average of the whole iris surface. Preliminary results suggest that hyperspectral imaging of the iris can provide much more morphological and spectral information with respect to conventional qualitative colorimetric methods.

A multi-approach feature extractions for iris recognition

NASA Astrophysics Data System (ADS)

Sanpachai, H.; Settapong, M.

2014-04-01

Biometrics is a promising technique that is used to identify individual traits and characteristics. Iris recognition is one of the most reliable biometric methods. As iris texture and color is fully developed within a year of birth, it remains unchanged throughout a person's life. Contrary to fingerprint, which can be altered due to several aspects including accidental damage, dry or oily skin and dust. Although iris recognition has been studied for more than a decade, there are limited commercial products available due to its arduous requirement such as camera resolution, hardware size, expensive equipment and computational complexity. However, at the present time, technology has overcome these obstacles. Iris recognition can be done through several sequential steps which include pre-processing, features extractions, post-processing, and matching stage. In this paper, we adopted the directional high-low pass filter for feature extraction. A box-counting fractal dimension and Iris code have been proposed as feature representations. Our approach has been tested on CASIA Iris Image database and the results are considered successful.

Characterization of iris pattern stretches and application to the measurement of roll axis eye movements.

PubMed

Nishiyama, Junpei; Hashimoto, Tsutomu; Sakashita, Yusuke; Fujiyoshi, Hironobu; Hirata, Yutaka

2008-01-01

Eye movements are utilized in many scientific studies as a probe that reflects the neural representation of 3 dimensional extrapersonal space. This study proposes a method to accurately measure the roll component of eye movements under the conditions in which the pupil diameter changes. Generally, the iris pattern matching between a reference and a test iris image is performed to estimate roll angle of the test image. However, iris patterns are subject to change when the pupil size changes, thus resulting in less accurate roll angle estimation if the pupil sizes in the test and reference images are different. We characterized non-uniform iris pattern contraction/expansion caused by pupil dilation/constriction, and developed an algorithm to convert an iris pattern with an arbitrary pupil size into that with the same pupil size as the reference iris pattern. It was demonstrated that the proposed method improved the accuracy of the measurement of roll eye movement by up to 76.9%.

Feature and score fusion based multiple classifier selection for iris recognition.

PubMed

Islam, Md Rabiul

2014-01-01

The aim of this work is to propose a new feature and score fusion based iris recognition approach where voting method on Multiple Classifier Selection technique has been applied. Four Discrete Hidden Markov Model classifiers output, that is, left iris based unimodal system, right iris based unimodal system, left-right iris feature fusion based multimodal system, and left-right iris likelihood ratio score fusion based multimodal system, is combined using voting method to achieve the final recognition result. CASIA-IrisV4 database has been used to measure the performance of the proposed system with various dimensions. Experimental results show the versatility of the proposed system of four different classifiers with various dimensions. Finally, recognition accuracy of the proposed system has been compared with existing N hamming distance score fusion approach proposed by Ma et al., log-likelihood ratio score fusion approach proposed by Schmid et al., and single level feature fusion approach proposed by Hollingsworth et al.

Engineering challenges of operating year-round portable seismic stations at high-latitude

NASA Astrophysics Data System (ADS)

Beaudoin, Bruce; Carpenter, Paul; Hebert, Jason; Childs, Dean; Anderson, Kent

2017-04-01

Remote portable seismic stations are, in most cases, constrained by logistics and cost. High latitude operations introduce environmental, technical and logistical challenges that require substantially more engineering work to ensure robust, high quality data return. Since 2006, IRIS PASSCAL has been funded by NSF to develop, deploy, and maintain a pool of polar specific seismic stations. Here, we describe our latest advancements to mitigate the challenges of high-latitude, year-round station operation. The IRIS PASSCAL program has supported high-latitude deployments since the late 1980s. These early deployments were largely controlled source, summer only experiments. In early 2000 PASSCAL users began proposing year-round deployments of broadband stations in some of the harshest environments on the planet. These early year-round deployments were stand-alone (no telemetry) stations largely designed to operate during summer months and then run as long as possible during the winter with hopes the stations would revive come following summer. In 2006 and in collaboration with UNAVCO, we began developing communications, power systems, and enclosures to extend recording to year-round. Since this initial effort, PASSCAL continued refinement to power systems, enclosure design and manufacturability, and real-time data communications. Several sensor and data logger manufacturers have made advances in cold weather performance and delivered newly designed instruments that have furthered our ability to successfully run portable stations at high-latitude with minimal logistics - reducing size and weight of instruments and infrastructure. All PASSCAL polar engineering work is openly shared through our website: www.passcal.nmt.edu/content/polar

IRIS Toxicological Review of Tetrahydrofuran (THF) (External ...

EPA Pesticide Factsheets

EPA is conducting a peer review and public comment of the scientific basis supporting the human health hazard and dose-response assessment of tetrahydrofuran (THF) that when finalized will appear on the Integrated Risk Information System (IRIS) database. EPA is undertaking an Integrated Risk Information System (IRIS) health assessment for tetrahydrofuran. IRIS is an EPA database containing Agency scientific positions on potential adverse human health effects that may result from chronic (or lifetime) exposure to chemicals in the environment. IRIS contains chemical-specific summaries of qualitative and quantitative health information in support of two steps of the risk assessment paradigm, i.e., hazard identification and dose-response evaluation. IRIS assessments are used in combination with specific situational exposure assessment information to evaluate potential public health risk associated with environmental contaminants.

New methods in iris recognition.

PubMed

Daugman, John

2007-10-01

This paper presents the following four advances in iris recognition: 1) more disciplined methods for detecting and faithfully modeling the iris inner and outer boundaries with active contours, leading to more flexible embedded coordinate systems; 2) Fourier-based methods for solving problems in iris trigonometry and projective geometry, allowing off-axis gaze to be handled by detecting it and "rotating" the eye into orthographic perspective; 3) statistical inference methods for detecting and excluding eyelashes; and 4) exploration of score normalizations, depending on the amount of iris data that is available in images and the required scale of database search. Statistical results are presented based on 200 billion iris cross-comparisons that were generated from 632500 irises in the United Arab Emirates database to analyze the normalization issues raised in different regions of receiver operating characteristic curves.

COMGEN - A PROGRAM FOR GENERATING FINITE ELEMENT MODELS OF COMPOSITE MATERIALS AT THE MICRO LEVEL (SGI IRIS VERSION)

NASA Technical Reports Server (NTRS)

Melis, M. E.

1994-01-01

A significant percentage of time spent in a typical finite element analysis is taken up in the modeling and assignment of loads and constraints. This process not only requires the analyst to be well-versed in the art of finite element modeling, but also demands familiarity with some sort of preprocessing software in order to complete the task expediently. COMGEN (COmposite Model GENerator) is an interactive FORTRAN program which can be used to create a wide variety of finite element models of continuous fiber composite materials at the micro level. It quickly generates batch or "session files" to be submitted to the finite element pre- and post-processor program, PATRAN. (PDA Engineering, Costa Mesa, CA.) In modeling a composite material, COMGEN assumes that its constituents can be represented by a "unit cell" of a fiber surrounded by matrix material. Two basic cell types are available. The first is a square packing arrangement where the fiber is positioned in the center of a square matrix cell. The second type, hexagonal packing, has the fiber centered in a hexagonal matrix cell. Different models can be created using combinations of square and hexagonal packing schemes. Variations include two- and three- dimensional cases, models with a fiber-matrix interface, and different constructions of unit cells. User inputs include fiber diameter and percent fiber-volume of the composite to be analyzed. In addition, various mesh densities, boundary conditions, and loads can be assigned to the models within COMGEN. The PATRAN program then uses a COMGEN session file to generate finite element models and their associated loads which can then be translated to virtually any finite element analysis code such as NASTRAN or MARC. COMGEN is written in FORTRAN 77 and has been implemented on DEC VAX series computers under VMS and SGI IRIS series workstations under IRIX. If the user has the PATRAN package available, the output can be graphically displayed. Without PATRAN, the output is tabular. The VAX VMS version is available on a 5.25 inch 360K MS-DOS format diskette (standard distribution media) or a 9-track 1600 BPI DEC VAX FILES-11 format magnetic tape, and it requires about 124K of main memory. The standard distribution media for the IRIS version is a .25 inch streaming magnetic tape cartridge in UNIX tar format. The memory requirement for the IRIS version is 627K. COMGEN was developed in 1990. DEC, VAX and VMS are trademarks of Digital Equipment Corporation. PATRAN is a registered trademark of PDA Engineering. SGI IRIS and IRIX are trademarks of Silicon Graphics, Inc. MS-DOS is a registered trademark of Microsoft Corporation. UNIX is a registered trademark of AT&T.

IRIS Toxicological Review of Tert-Butyl Alcohol (Tert-Butanol) ...

EPA Pesticide Factsheets

The IRIS Toxicological Review of tert-Butyl Alcohol (tert-Butanol) was released for external peer review in June 2017. EPA’s Science Advisory Board’s (SAB) Chemical Assessment Advisory Committee (CAAC) will conduct a peer review of the scientific basis supporting the tert-butanol assessment and release a final report of their review. Information regarding the peer review can be found on the SAB website. EPA is conducting an Integrated Risk Information System (IRIS) health assessment for tert-butanol. The outcome of this project is a Toxicological Review and IRIS Summary for tert-butanol that will be entered into the IRIS database.

Iris metastasis as a first manifestation of lung adenocarcinoma.

PubMed

Hernández-Da Mota, S E; Ulaje-Nuñez, J M; Salinas-Gallegos, J L; Rodríguez-Reyes, A

2018-03-23

To describe a case of lung adenocarcinoma for which the first clinical manifestation was an iris metastasis. A 76-year-old male patient came for consultation referring a «pinkish speck» on his right eye. On biomicroscopy examination, a mass was found on the iris of the right eye. Subsequent systemic work-up of the patient revealed a left lung adenocarcinoma. Although uncommon, iris metastasis secondary to lung cancer should be part of differential diagnosis in iris tumours. Copyright © 2018 Sociedad Española de Oftalmología. Publicado por Elsevier España, S.L.U. All rights reserved.

Iris coloboma in one eye and pigment dispersion syndrome in the fellow eye.

PubMed

Galvis, Virgilio; Tello, Alejandro; Valarezo, Paul; Prada, Angélica M

2013-05-22

We report a case of a 43-year-old patient with coloboma of the iris, zonule, ciliary body, choroid and retina in the right eye and pigment dispersion syndrome in the left eye. Considering the hypothesis of the pigment dispersion syndrome pathogenesis in which a difference of pressures in the anterior and posterior chambers creates a posterior convexity of the iris leading to reverse pupillary block, iris touch and consequently causing pigment dispersion, we suggest that the presence of an iris coloboma, by equalising the pressures in the two chambers, prevented the onset of syndrome in that eye.

Pigment dispersion syndrome and pigmentary glaucoma--a major review.

PubMed

Niyadurupola, Nuwan; Broadway, David C

2008-12-01

Pigment dispersion syndrome (PDS) is an interesting condition that can lead to secondary open angle glaucoma. Pigmentary glaucoma is primarily a disease of young people, myopes and men. PDS is characterized by the presence of Krukenberg spindles, iris trans-illumination defects, trabecular meshwork pigmentation and backward bowing of the iris. Posterior bowing of the iris causes rubbing of the pigmented iris epithelium against lens structures, liberation of pigment and trabecular meshwork changes that result in reduced aqueous outflow with the risk of glaucoma. Peripheral laser iridotomy can reverse backward bowing of the iris and may prevent progression of pigmentary glaucoma.

Iris Transponder-Communications and Navigation for Deep Space

NASA Technical Reports Server (NTRS)

Duncan, Courtney B.; Smith, Amy E.; Aguirre, Fernando H.

2014-01-01

The Jet Propulsion Laboratory has developed the Iris CubeSat compatible deep space transponder for INSPIRE, the first CubeSat to deep space. Iris is 0.4 U, 0.4 kg, consumes 12.8 W, and interoperates with NASA's Deep Space Network (DSN) on X-Band frequencies (7.2 GHz uplink, 8.4 GHz downlink) for command, telemetry, and navigation. This talk discusses the Iris for INSPIRE, it's features and requirements; future developments and improvements underway; deep space and proximity operations applications for Iris; high rate earth orbit variants; and ground requirements, such as are implemented in the DSN, for deep space operations.

Extending the imaging volume for biometric iris recognition.

PubMed

Narayanswamy, Ramkumar; Johnson, Gregory E; Silveira, Paulo E X; Wach, Hans B

2005-02-10

The use of the human iris as a biometric has recently attracted significant interest in the area of security applications. The need to capture an iris without active user cooperation places demands on the optical system. Unlike a traditional optical design, in which a large imaging volume is traded off for diminished imaging resolution and capacity for collecting light, Wavefront Coded imaging is a computational imaging technology capable of expanding the imaging volume while maintaining an accurate and robust iris identification capability. We apply Wavefront Coded imaging to extend the imaging volume of the iris recognition application.

Jupiter's para-H2 distribution from SOFIA/FORCAST and Voyager/IRIS 17-37 μm spectroscopy

NASA Astrophysics Data System (ADS)

Fletcher, Leigh N.; de Pater, I.; Reach, W. T.; Wong, M.; Orton, G. S.; Irwin, P. G. J.; Gehrz, R. D.

2017-04-01

Spatially resolved maps of Jupiter's far-infrared 17-37 μm hydrogen-helium collision-induced spectrum were acquired by the FORCAST instrument on the Stratospheric Observatory for Infrared Astronomy (SOFIA) in May 2014. Spectral scans in two grisms covered the broad S(0) and S(1) absorption lines, in addition to contextual imaging in eight broad-band filters (5-37 μm) with spatial resolutions of 2-4″. The spectra were inverted to map the zonal-mean temperature and para-H2 distribution (fp, the fraction of the para spin isomer with respect to the ortho spin isomer) in Jupiter's upper troposphere (the 100-700 mbar range). We compared these to a reanalysis of Voyager-1 and -2 IRIS spectra covering the same spectral range. Tropospheric temperature contrasts match those identified by Voyager in 1979, within the limits of temporal variability consistent with previous investigations. Para-H2 increases from equator to pole, with low-fp air at the equator representing sub-equilibrium conditions (i.e., less para-H2 than expected from thermal equilibration), and high-fp air and possible super-equilibrium at higher latitudes. In particular, we confirm the continued presence of a region of high-fp air at high northern latitudes discovered by Voyager/IRIS, and an asymmetry with generally higher fp in the north than in the south. Far-IR aerosol opacity is not required to fit the data, but cannot be completely ruled out. We note that existing collision-induced absorption databases lack opacity from (H2)2 dimers, leading to under-prediction of the absorption near the S(0) and S(1) peaks. There appears to be no spatial correlation between para-H2 and tropospheric ammonia, phosphine and cloud opacity derived from Voyager/IRIS at mid-infrared wavelengths (7-15 μm). We note, however, that para-H2 tracks the similar latitudinal distribution of aerosols within Jupiter's upper tropospheric and stratospheric hazes observed in reflected sunlight, suggesting that catalysis of hydrogen equilibration within the hazes (and not the main clouds) may govern the equator-to-pole gradient, with conditions closer to equilibrium at higher latitudes. This gradient is superimposed onto smaller-scale variations associated with regional advection of para-H2 at the equator and poles.

4D computerized ionospheric tomography by using GPS measurements and IRI-Plas model

NASA Astrophysics Data System (ADS)

Tuna, Hakan; Arikan, Feza; Arikan, Orhan

2016-07-01

Ionospheric imaging is an important subject in ionospheric studies. GPS based TEC measurements provide very accurate information about the electron density values in the ionosphere. However, since the measurements are generally very sparse and non-uniformly distributed, computation of 3D electron density estimation from measurements alone is an ill-defined problem. Model based 3D electron density estimations provide physically feasible distributions. However, they are not generally compliant with the TEC measurements obtained from GPS receivers. In this study, GPS based TEC measurements and an ionosphere model known as International Reference Ionosphere Extended to Plasmasphere (IRI-Plas) are employed together in order to obtain a physically accurate 3D electron density distribution which is compliant with the real measurements obtained from a GPS satellite - receiver network. Ionospheric parameters input to the IRI-Plas model are perturbed in the region of interest by using parametric perturbation models such that the synthetic TEC measurements calculated from the resultant 3D electron density distribution fit to the real TEC measurements. The problem is considered as an optimization problem where the optimization parameters are the parameters of the parametric perturbation models. Proposed technique is applied over Turkey, on both calm and storm days of the ionosphere. Results show that the proposed technique produces 3D electron density distributions which are compliant with IRI-Plas model, GPS TEC measurements and ionosonde measurements. The effect of the GPS receiver station number on the performance of the proposed technique is investigated. Results showed that 7 GPS receiver stations in a region as large as Turkey is sufficient for both calm and storm days of the ionosphere. Since the ionization levels in the ionosphere are highly correlated in time, the proposed technique is extended to the time domain by applying Kalman based tracking and smoothing approaches onto the obtained results. Combining Kalman methods with the proposed 3D CIT technique creates a robust 4D ionospheric electron density estimation model, and has the advantage of decreasing the computational cost of the proposed method. Results applied on both calm and storm days of the ionosphere show that, new technique produces more robust solutions especially when the number of GPS receiver stations in the region is small. This study is supported by TUBITAK 114E541, 115E915 and Joint TUBITAK 114E092 and AS CR 14/001 projects.

Three-dimensional modeling of the neutron spectrum to infer plasma conditions in cryogenic inertial confinement fusion implosions

NASA Astrophysics Data System (ADS)

Weilacher, F.; Radha, P. B.; Forrest, C.

2018-04-01

Neutron-based diagnostics are typically used to infer compressed core conditions such as areal density and ion temperature in deuterium-tritium (D-T) inertial confinement fusion (ICF) implosions. Asymmetries in the observed neutron-related quantities are important to understanding failure modes in these implosions. Neutrons from fusion reactions and their subsequent interactions including elastic scattering and neutron-induced deuteron breakup reactions are tracked to create spectra. It is shown that background subtraction is important for inferring areal density from backscattered neutrons and is less important for the forward-scattered neutrons. A three-dimensional hydrodynamic simulation of a cryogenic implosion on the OMEGA Laser System [Boehly et al., Opt. Commun. 133, 495 (1997)] using the hydrodynamic code HYDRA [Marinak et al., Phys. Plasmas 8, 2275 (2001)] is post-processed using the tracking code IRIS3D. It is shown that different parts of the neutron spectrum from the view can be mapped into different regions of the implosion, enabling an inference of an areal-density map. It is also shown that the average areal-density and an areal-density map of the compressed target can be reconstructed with a finite number of detectors placed around the target chamber. Ion temperatures are inferred from the width of the D-D and D-T fusion neutron spectra. Backgrounds can significantly alter the inferred ion temperatures from the D-D reaction, whereas they insignificantly influence the inferred D-T ion temperatures for the areal densities typical of OMEGA implosions. Asymmetries resulting in fluid flow in the core are shown to influence the absolute inferred ion temperatures from both reactions, although relative inferred values continue to reflect the underlying asymmetry pattern. The work presented here is part of the wide range of the first set of studies performed with IRIS3D. This code will continue to be used for post-processing detailed hydrodynamic simulations and interpreting observed neutron spectra in ICF implosions.

Immune Reconstitution Inflammatory Syndrome Unmasking or Worsening AIDS-Related Progressive Multifocal Leukoencephalopathy: A Literature Review.

PubMed

Fournier, Anna; Martin-Blondel, Guillaume; Lechapt-Zalcman, Emmanuèle; Dina, Julia; Kazemi, Apolline; Verdon, Renaud; Mortier, Emmanuel; de La Blanchardière, Arnaud

2017-01-01

Incidence of progressive multifocal leukoencephalopathy (PML) in HIV-infected patients has declined in the combined antiretroviral therapy (cART) era although a growing number of acquired immunodeficiency syndrome (AIDS)-related PML-immune reconstitution inflammatory syndromes (PML-IRIS) have been published during the same period. Therapeutic management of PML-IRIS is not consensual and mainly relies on corticosteroids. Our main aim was, in addition to provide a thoughtful analysis of published PML-IRIS cases, to assess the benefit of corticosteroids in the management of PML-IRIS, focusing on confirmed cases. We performed a literature review of the 46 confirmed cases of PML-IRIS cases occurring in HIV-infected patients from 1998 to September 2016 (21 unmasking and 25 paradoxical PML-IRIS). AIDS-related PML-IRIS patients were mostly men (sex ratio 4/1) with a median age of 40.5 years (range 12-66). Median CD4 T cell count before cART and at PML-IRIS onset was 45/μl (0-301) and 101/μl (20-610), respectively. After cART initiation, PML-IRIS occurred within a median timescale of 38 days (18-120). Clinical signs were motor deficits (69%), speech disorders (36%), cognitive disorders (33%), cerebellar ataxia (28%), and visual disturbances (23%). Brain MRI revealed hyperintense areas on T2-weighted sequences and FLAIR images (76%) and suggestive contrast enhancement (87%). PCR for John Cunningham virus (JCV) in cerebrospinal fluid (CSF) was positive in only 84% of cases; however, when performed, brain biopsy confirmed diagnosis of PML in 90% of cases and demonstrated histological signs of IRIS in 95% of cases. Clinical worsening related to PML-IRIS and leading to death was observed in 28% of cases. Corticosteroids were prescribed in 63% of cases and maraviroc in one case. Statistical analysis failed to demonstrate significant benefit from steroid treatment, despite spectacular improvement in certain cases. Diagnosis of PML-IRIS should be considered in HIV-infected patients with worsening neurological symptoms after initiation or resumption of effective cART, independently of CD4 cell count prior to cART. If PCR for JCV is negative in CSF, brain biopsy should be discussed. Only large multicentric randomized trials could potentially demonstrate the possible efficacy of corticosteroids and/or CCR5 antagonists in the management of PML-IRIS.

Immune Reconstitution Inflammatory Syndrome Unmasking or Worsening AIDS-Related Progressive Multifocal Leukoencephalopathy: A Literature Review

PubMed Central

Fournier, Anna; Martin-Blondel, Guillaume; Lechapt-Zalcman, Emmanuèle; Dina, Julia; Kazemi, Apolline; Verdon, Renaud; Mortier, Emmanuel; de La Blanchardière, Arnaud

2017-01-01

Incidence of progressive multifocal leukoencephalopathy (PML) in HIV-infected patients has declined in the combined antiretroviral therapy (cART) era although a growing number of acquired immunodeficiency syndrome (AIDS)-related PML-immune reconstitution inflammatory syndromes (PML-IRIS) have been published during the same period. Therapeutic management of PML-IRIS is not consensual and mainly relies on corticosteroids. Our main aim was, in addition to provide a thoughtful analysis of published PML-IRIS cases, to assess the benefit of corticosteroids in the management of PML-IRIS, focusing on confirmed cases. We performed a literature review of the 46 confirmed cases of PML-IRIS cases occurring in HIV-infected patients from 1998 to September 2016 (21 unmasking and 25 paradoxical PML-IRIS). AIDS-related PML-IRIS patients were mostly men (sex ratio 4/1) with a median age of 40.5 years (range 12–66). Median CD4 T cell count before cART and at PML-IRIS onset was 45/μl (0–301) and 101/μl (20–610), respectively. After cART initiation, PML-IRIS occurred within a median timescale of 38 days (18–120). Clinical signs were motor deficits (69%), speech disorders (36%), cognitive disorders (33%), cerebellar ataxia (28%), and visual disturbances (23%). Brain MRI revealed hyperintense areas on T2-weighted sequences and FLAIR images (76%) and suggestive contrast enhancement (87%). PCR for John Cunningham virus (JCV) in cerebrospinal fluid (CSF) was positive in only 84% of cases; however, when performed, brain biopsy confirmed diagnosis of PML in 90% of cases and demonstrated histological signs of IRIS in 95% of cases. Clinical worsening related to PML-IRIS and leading to death was observed in 28% of cases. Corticosteroids were prescribed in 63% of cases and maraviroc in one case. Statistical analysis failed to demonstrate significant benefit from steroid treatment, despite spectacular improvement in certain cases. Diagnosis of PML-IRIS should be considered in HIV-infected patients with worsening neurological symptoms after initiation or resumption of effective cART, independently of CD4 cell count prior to cART. If PCR for JCV is negative in CSF, brain biopsy should be discussed. Only large multicentric randomized trials could potentially demonstrate the possible efficacy of corticosteroids and/or CCR5 antagonists in the management of PML-IRIS. PMID:28588577

BRCA1-IRIS Overexpression Promotes Formation of Aggressive Breast Cancers

PubMed Central

Shimizu, Yoshiko; Luk, Hugh; Horio, David; Miron, Penelope; Griswold, Michael; Iglehart, Dirk; Hernandez, Brenda; Killeen, Jeffrey; ElShamy, Wael M.

2012-01-01

Introduction Women with HER2+ or triple negative/basal-like (TN/BL) breast cancers succumb to their cancer rapidly due, in part to acquired Herceptin resistance and lack of TN/BL-targeted therapies. BRCA1-IRIS is a recently discovered, 1399 residue, BRCA1 locus alternative product, which while sharing 1365 residues with the full-length product of this tumor suppressor gene, BRCA1/p220, it has oncoprotein-like properties. Here, we examine whether BRCA1-IRIS is a valuable treatment target for HER2+ and/or TN/BL tumors. Methodology/Principal Findings Immunohistochemical staining of large cohort of human breast tumor samples using new monoclonal anti-BRCA1-IRIS antibody, followed by correlation of BRCA1-IRIS expression with that of AKT1, AKT2, p-AKT, survivin and BRCA1/p220, tumor status and age at diagnosis. Generation of subcutaneous tumors in SCID mice using human mammary epithelial (HME) cells overexpressing TERT/LT/BRCA1-IRIS, followed by comparing AKT, survivin, and BRCA1/p220 expression, tumor status and aggressiveness in these tumors to that in tumors developed using TERT/LT/RasV12-overexpressing HME cells. Induction of primary and invasive rat mammary tumors using the carcinogen N-methyl-N-nitrosourea (NMU), followed by analysis of rat BRCA1-IRIS and ERα mRNA levels in these tumors. High BRCA1-IRIS expression was detected in the majority of human breast tumors analyzed, which was positively correlated with that of AKT1-, AKT2-, p-AKT-, survivin, but negatively with BRCA1/p220 expression. BRCA1-IRIS-positivity induced high-grade, early onset and metastatic HER2+ or TN/BL tumors. TERT/LT/BRCA1-IRIS overexpressing HME cells formed invasive subcutaneous tumors that express high AKT1, AKT2, p-AKT and vimentin, but no CK19, p63 or BRCA1/p220. NMU-induced primary and invasive rat breast cancers expressed high levels of rat BRCA1-IRIS mRNA but low levels of rat ERα mRNA. Conclusion/Significance BRCA1-IRIS overexpression triggers aggressive breast tumor formation, especially in patients with HER2+ or TN/BL subtypes. We propose that BRCA1-IRIS inhibition may be pursued as a novel therapeutic option to treat these aggressive breast tumor subtypes. PMID:22511931

HyspIRI Low Latency Concept and Benchmarks

NASA Technical Reports Server (NTRS)

Mandl, Dan

2010-01-01

Topics include HyspIRI low latency data ops concept, HyspIRI data flow, ongoing efforts, experiment with Web Coverage Processing Service (WCPS) approach to injecting new algorithms into SensorWeb, low fidelity HyspIRI IPM testbed, compute cloud testbed, open cloud testbed environment, Global Lambda Integrated Facility (GLIF) and OCC collaboration with Starlight, delay tolerant network (DTN) protocol benchmarking, and EO-1 configuration for preliminary DTN prototype.

Iridium Interfacial Stack (IRIS)

NASA Technical Reports Server (NTRS)

Spry, David James (Inventor)

2015-01-01

An iridium interfacial stack ("IrIS") and a method for producing the same are provided. The IrIS may include ordered layers of TaSi.sub.2, platinum, iridium, and platinum, and may be placed on top of a titanium layer and a silicon carbide layer. The IrIS may prevent, reduce, or mitigate against diffusion of elements such as oxygen, platinum, and gold through at least some of its layers.

Long-term results after artificial iris implantation in patients with aniridia.

PubMed

Rickmann, Annekatrin; Szurman, Peter; Januschowski, Kai; Waizel, Maria; Spitzer, Martin S; Boden, Karl T; Szurman, Gesine B

2016-07-01

The custom-made, flexible artificial iris developed by HumanOptics and Koch can reconstruct the anterior segment of patients with aniridia. The aim of this study was to evaluate the long-term clinical outcome and complication spectrum after artificial iris implantation and the role of the embedded fiber mesh in view of specific complications. In this retrospective interventional case series, patients received an artificial iris between 2004 and 2013. Only eyes with a minimum follow-up period of 2 years were included. Indications were congenital, traumatic, or iatrogenic aniridia. The artificial iris was used either with or without embedded fiber mesh for partial or full prostheses. We included 34 patients (mean age 48.8 years; SD ±17.2) with a mean follow-up of 50.0 months (SD ±18.9 months). No repositioning of prostheses was necessary. In cases of keratopathy (17.6 %) visual function increased from baseline mean 1.6 logMAR (SD ±0.7) to 1.2 logMAR (SD ±0.7) after artificial iris implantation. The remaining iris tissue darkened during the follow-up in 23.5 % (83.3 % with and 10.7 % without mesh), 8.8 % developed glaucoma (50 % with and 0 % without mesh) and 14.7 % needed consecutive surgery after prostheses implantation (50 % with and 7.1 % without mesh). In three out of seven trauma cases (42.9 %) silicone oil was spilled into the anterior chamber after 2.5 years on average. The artificial iris prosthesis revealed a good clinical outcome in terms of long-term stability, cosmetic appearance, visual function, and represents a good functional iris diaphragm for compartmentalisation. Complications such as glaucoma, darkening of iris tissue, and need for consecutive anterior segment surgery are clearly associated with implants with integrated fiber mesh, but not to those without. Hence, the use of full iris prostheses without embedded fiber mesh, even in cases with remnant iris, and the use of slightly smaller implants than officially recommended may be beneficial.

Comparison of GPS TEC variations with Holt-Winter method and IRI-2012 over Langkawi, Malaysia

NASA Astrophysics Data System (ADS)

Elmunim, N. A.; Abdullah, M.; Hasbi, A. M.; Bahari, S. A.

2017-07-01

The Total Electron Content (TEC) is the ionospheric parameter that has the main effect on radio wave propagation. Therefore, it is crucial to evaluate the performance of the TEC models for the further improvement of the ionospheric modelling in equatorial regions. This work presents an analysis of the TEC, derived from the GPS Ionospheric Scintillation and TEC Monitor (GISTM) receiver at the Langkawi station, Malaysia, located at the geographic coordinates of 6.19°N, 99.51°E and the geomagnetic coordinates of 3.39°S, 172.42°E. The diurnal, monthly and seasonal variations in 2014 of the observed GPS-TEC were compared with the statistical Holt-Winter method and a recent version of the International Reference Ionosphere model (IRI-2012), using three different topside options of an electron density, which are the IRI-2001, IRI01-corr and NeQuick. The maximum peaks of the GPS-TEC were observed in the post-noon time and the minimum was observed during the early morning time. In addition, in monthly variations the Holt-Winter and the IRI-2012 topside options showed an underestimation that was in agreement with the GPS-TEC, except for the IRI-2001 model which showed an overestimation in June, July and August. Regarding the seasonal variation of the GPS-TEC, the lowest values were observed during summer and it reached its maximum value during the equinox season. The IRI-2001 showed the highest value of percentage deviation compared to the IRI01-corr, NeQuick and Holt-Winter method. Therefore, the accuracy of the models was found to be approximately 95% in the Holt-Winter method, 75% in the IRI01-corr, 73% in the NeQuick and 66% in the IRI-2001 model. Hence, it can be inferred that the Holt-Winter method showed a higher performance and better estimates of the TEC compared to the IRI01-corr and NeQuick, while the IRI-2001 showed a poor predictive performance in the equatorial region over Malaysia.

Comparison of GPS-derived TEC with IRI-2012 and IRI-2007 TEC predictions at Surat, a location around the EIA crest in the Indian sector, during the ascending phase of solar cycle 24

NASA Astrophysics Data System (ADS)

Patel, N. C.; Karia, S. P.; Pathak, K. N.

2017-07-01

This paper presents a comparison of GPS-derived TEC with IRI-2012 and IRI-2007 TEC Predictions at Surat (21.16°N Geographic latitude, 72.78°E Geographic longitude, 12.90°N Geomagnetic latitude) a location around the Equatorial Ionisation Anomaly (EIA) crest in the Indian sector, during the Ascending Phase of Solar Cycle 24, for a period of three years (January 2010-December 2012). In this comparison, plasmaspheric electron content (PEC) contribution to the GPS-TEC has been removed. It is observed that percentage PEC contribution to the GPS-TEC varies from about ∼15% (at the noon local time) to about ∼30% (at the morning local time). From the monthly comparison of GPS-TEC with IRI-TEC, it is observed that, TEC predicted by both the models overestimates in June-2012 and underestimates TEC in November-2011, December-2011 and March-2011. For all other months IRI estimates the TEC well. From the seasonal comparison, it is observed that the peak time appears ∼1-h later than the actual peak time in Winter 2010, Summer 2011, and Equinox 2010 and 2012 (the result suggest that it may be due to discrepancies/disagreement of both the versions of the IRI model in estimating the peak density as well as the thickness and shape parameters of the electron density profiles). For the Summer season, the IRI-TEC estimates the TEC well for all the years. Further, the seasonal variation of the GPS-TEC for all the three years matches well with IRI-2012 model compared to IRI-2007 model. Also, the mean annual TEC is predicted well by both the versions of the IRI model.

Head-to-head comparison of structurally unrelated dipeptidyl peptidase 4 inhibitors in the setting of renal ischemia reperfusion injury.

PubMed

Reichetzeder, Christoph; von Websky, Karoline; Tsuprykov, Oleg; Mohagheghi Samarin, Azadeh; Falke, Luise Gabriele; Dwi Putra, Sulistyo Emantoko; Hasan, Ahmed Abdallah; Antonenko, Viktoriia; Curato, Caterina; Rippmann, Jörg; Klein, Thomas; Hocher, Berthold

2017-07-01

Results regarding protective effects of dipeptidyl peptidase 4 (DPP4) inhibitors in renal ischaemia-reperfusion injury (IRI) are conflicting. Here we have compared structurally unrelated DPP4 inhibitors in a model of renal IRI. IRI was induced in uninephrectomized male rats by renal artery clamping for 30 min. The sham group was uninephrectomized but not subjected to IRI. DPP4 inhibitors or vehicle were given p.o. once daily on three consecutive days prior to IRI: linagliptin (1.5 mg·kg -1 ·day -1 ), vildagliptin (8 mg·kg -1 ·day -1 ) and sitagliptin (30 mg·kg -1 ·day -1 ). An additional group received sitagliptin until study end (before IRI: 30 mg·kg -1 ·day -1 ; after IRI: 15 mg·kg -1 ·day -1 ). Plasma-active glucagon-like peptide type 1 (GLP-1) increased threefold to fourfold in all DPP4 inhibitor groups 24 h after IRI. Plasma cystatin C, a marker of GFR, peaked 48 h after IRI. Compared with the placebo group, DPP4 inhibition did not reduce increased plasma cystatin C levels. DPP4 inhibitors ameliorated histopathologically assessed tubular damage with varying degrees of drug-specific efficacies. Renal osteopontin expression was uniformly reduced by all DPP4 inhibitors. IRI-related increased renal cytokine expression was not decreased by DPP4 inhibition. Renal DPP4 activity at study end was significantly inhibited in the linagliptin group, but only numerically reduced in the prolonged/dose-adjusted sitagliptin group. Active GLP-1 plasma levels at study end were increased only in the prolonged/dose-adjusted sitagliptin treatment group. In rats with renal IRI, DPP4 inhibition did not alter plasma cystatin C, a marker of glomerular function, but may protect against tubular damage. © 2017 The Authors. British Journal of Pharmacology published by John Wiley & Sons Ltd on behalf of British Pharmacological Society.

An inverse method to determine the mechanical properties of the iris in vivo

PubMed Central

2014-01-01

Background Understanding the mechanical properties of the iris can help to have an insight into the eye diseases with abnormalities of the iris morphology. Material parameters of the iris were simply calculated relying on the ex vivo experiment. However, the mechanical response of the iris in vivo is different from that ex vivo, therefore, a method was put forward to determine the material parameters of the iris using the optimization method in combination with the finite element method based on the in vivo experiment. Material and methods Ocular hypertension was induced by rapid perfusion to the anterior chamber, during perfusion intraocular pressures in the anterior and posterior chamber were record by sensors, images of the anterior segment were captured by the ultrasonic system. The displacement of the characteristic points on the surface of the iris was calculated. A finite element model of the anterior chamber was developed using the ultrasonic image before perfusion, the multi-island genetic algorithm was employed to determine the material parameters of the iris by minimizing the difference between the finite element simulation and the experimental measurements. Results Material parameters of the iris in vivo were identified as the iris was taken as a nearly incompressible second-order Ogden solid. Values of the parameters μ1, α1, μ2 and α2 were 0.0861 ± 0.0080 MPa, 54.2546 ± 12.7180, 0.0754 ± 0.0200 MPa, and 48.0716 ± 15.7796 respectively. The stability of the inverse finite element method was verified, the sensitivity of the model parameters was investigated. Conclusion Material properties of the iris in vivo could be determined using the multi-island genetic algorithm coupled with the finite element method based on the experiment. PMID:24886660

Conventional alpha beta (αβ) T cells do not contribute to acute intestinal ischemia-reperfusion injury in mice.

PubMed

Yu, Yi; Feng, Xiaoyan; Vieten, Gertrud; Dippel, Stephanie; Imvised, Tawan; Gueler, Faikah; Ure, Benno M; Kuebler, Jochen F; Klemann, Christian

2017-01-01

Ischemia-reperfusion injury (IRI) is associated with significant patient mortality and morbidity. The complex cascade of IRI is incompletely understood, but inflammation is known to be a key mediator. In addition to the predominant innate immune responses, previous research has also indicated that αβ T cells contribute to IRI in various organ models. The aim of this study was to clarify the role αβ T cells play in IRI to the gut. Adult wild-type (WT) and αβ T cell-deficient mice were subjected to acute intestinal IRI with 30min ischemia followed by 4h reperfusion. The gene expression of pro-inflammatory cytokines was measured by qPCR, and the influx of leukocyte subpopulations in the gut was assessed via flow cytometry and histology. Pro-inflammatory cytokines in the serum were measured, and transaminases were assessed as an indicator of distant organ IRI. Intestinal IRI led to an increased expression of pro-inflammatory cytokines in the gut tissue and an influx of leukocytes that predominantly consisted of neutrophils and macrophages. Furthermore, intestinal IRI increased serum IL-6, TNF-α, and ALT/AST levels. The αβ T cell-deficient mice did not exhibit a more significant increase in pro-inflammatory cytokines in the gut or serum following IR than the WT mice. There was also no difference between WT- and αβ T cell-deficient mice in terms of neutrophil infiltration or macrophage activation. Furthermore, the increase in transaminases was equal in both groups indicating that the level of distant organ injury was comparable. An increasing body of evidence demonstrates that αβ T cells play a key role in IRI. In the gut, however, αβ T cells are not pivotal in the first hours following acute IRI as deficiency does not impact cytokine production, neutrophil recruitment, macrophage activation, or distant organ injury. Thus, αβ T cells may be considered innocent bystanders during the acute phase of intestinal IRI.

Clinical case definition and manifestations of paradoxical tuberculosis-associated immune reconstitution inflammatory syndrome.

PubMed

Manosuthi, Weerawat; Van Tieu, Hong; Mankatitham, Wiroj; Lueangniyomkul, Aroon; Ananworanich, Jintanat; Avihingsanon, Anchalee; Siangphoe, Umaporn; Klongugkara, Sukonsri; Likanonsakul, Sirirat; Thawornwan, Unchana; Suntisuklappon, Bussakorn; Sungkanuparph, Somnuek

2009-11-27

The International Network for the Study of HIV-associated IRIS (INSHI) recently published criteria for tuberculosis-associated immune reconstitution inflammatory syndrome (TB-IRIS) diagnosis. The performance of this definition and clinical manifestations of TB-IRIS were studied. Antiretroviral therapy-naive HIV/TB Thai patients receiving antituberculous therapy were enrolled during 2006-2007 and prospectively followed through 24 weeks of antiretroviral therapy. Patients were defined as having paradoxical TB-IRIS if they fulfilled the 'study definition' by French 2004 and were confirmed by an external reviewer. All were later compared by the classification according to 'INSHI-2008'. For the 126 patients, median baseline CD4 cell count was 43 cells/microl and HIV-1 RNA was 5.9 log(10) Y copies/ml. Seventy-three (58%) had extrapulmonary/disseminated TB. Twenty-two (18%) and 21 (17%) fulfilled TB-IRIS criteria according to the study definition and INSHI-2008 definition, respectively. Two (2%) were diagnosed by study definition only and one (1%) by INSHI-2008 definition only. Twenty (16%) were concordantly diagnosed by both definitions and 103 (82%) were consistently negative. Eighteen (82%) had worsening of a preexisting site, whereas four (18%) had TB-IRIS in a new location. Lymph node enlargement (73%) and fever (59%) were common in TB-IRIS. Sensitivity and specificity of INSHI-2008 was 91% (95% confidence interval, 72-98%) and 99% (95% confidence interval, 95-99.8%), respectively. Positive predictive value was 95% and negative predictive value was 98%. By multivariate analysis, factors predicting TB-IRIS were extrapulmonary TB (odds ratio, 8.63) and disseminated TB (odds ratio, 4.17). There was high concordance between the INSHI-2008 and French 2004 definition for TB-IRIS diagnosis in HIV/TB patients with relatively high rate of paradoxical TB-IRIS. This suggests that lack of HIV-1 RNA and CD4 cell count monitoring does not impede the ability to diagnose TB-IRIS.

TB-IRIS and remodelling of the T cell compartment in highly immunosuppressed HIV+ patients with TB: the CAPRI T (ANRS-12614) study

PubMed Central

Haridas, V.; Pean, P.; Jasenosky, L.D.; Madec, Y.; Laureillard, D.; Sok, T.; Sath, S.; Borand, L.; Marcy, O.; Chan, S.; Tsitsikov, E.; Delfraissy, J.-F.; Blanc, F.-X.; Goldfeld, A.E.

2015-01-01

Objective To investigate the impact of tuberculosis (TB)-associated immune reconstitution syndrome (IRIS) upon immunological recovery and the T cell compartment after initiation of TB and antiretroviral therapy (ART). Design and methods We prospectively evaluated T cell immunophenotypes by flow cytometry and cytokines by Luminex assays in a subset (n=154) of highly immunosuppressed HIV+ patients with TB from the CAMELIA randomized clinical trial. We compared findings from patients who developed TB-IRIS to findings from patients who did not develop TB-IRIS. Data were evaluated with mixed effect linear regression, Kaplan-Meier estimates, and Wilcoxon rank sum tests, and q-values were calculated to control for multiple comparisons. Results Development of TB-IRIS was associated with significantly greater pre-ART frequencies of HLA-DR+CD45RO+CD4+, CCR5+CD4+, OX40+CD4+, and Fas+ effector memory (EM) CD8+ T cells, and significantly elevated levels of plasma IL-6, IL-1β, IL-8, and IL-10 and viral load. Post-ART initiation, EM CD4+ and Fas+ EM CD4+ T cell frequencies significantly expanded, and central memory (CM) CD4+ T cell frequencies significantly contracted in patients who experienced TB-IRIS. By week 34 post-TB treatment initiation, EM/CM CD4+ T cell ratios were markedly higher in TB-IRIS versus non-TB-IRIS patients. Conclusions A distinct pattern of pre-ART T cell and cytokine markers appear to poise the immune response to develop TB-IRIS. Experience of TB-IRIS is then associated with long-term remodeling of the CD4+ T cell memory compartment towards an EM-dominated phenotype. We speculate that these pre- and post-ART TB-IRIS-associated immune parameters may contribute to superior immune control of TB/HIV co-infection and better clinical outcome. PMID:25486415

Comparison of clinical outcomes of iris fixation and scleral fixation as treatment for intraocular lens dislocation.

PubMed

Kim, Kyeong Hwan; Kim, Wan Soo

2015-09-01

To compare the efficacy and safety of iris fixation with scleral fixation in surgical repositioning of dislocated intraocular lenses (IOLs). Retrospective, consecutive, comparative interventional case series. setting: Referral hospital. Seventy-eight consecutive patients who underwent surgical repositioning of dislocated intraocular lenses using suturing to the sclera or iris. Forty-four eyes of 44 patients underwent scleral fixation and 35 eyes of 34 patients underwent iris fixation of dislocated intraocular lenses. Visual acuity, refractive stability, operation time, and perioperative complications, including recurrence of IOL dislocation. Corrected distance visual acuity (CDVA) improved significantly 1 month postoperatively in both groups (P < .01 each), and remained stable for 12 months. One week postoperatively, however, CDVA improved significantly in the scleral fixation (P = .040) but not in the iris fixation (P = .058) group. The amount of refractive error significantly diminished 1 day after surgery (P = .028 in the scleral fixation and P = .046 in the iris fixation group). For the astigmatic components, Jackson crossed cylinders equivalent to conventional cylinders of positive power at axes of 0 degrees (J0) and 45 degrees (J45), J45 differed significantly in the scleral fixation and iris fixation groups (P = .009), whereas J0 was similar (P > .05). Operation time was significantly shorter (P = .0007), while immediate postoperative inflammation was significantly more severe (P = .001), in the iris fixation than in the scleral fixation group. Recurrence rates were similar (P > .05), but the mean time to recurrence was significantly shorter in the iris fixation than in the scleral fixation group (P = .031). Iris fixation and scleral fixation techniques had similar efficacy in the repositioning of dislocated intraocular lenses. Although operation time was shorter for iris fixation, it had several disadvantages, including induced astigmatism, immediate postoperative inflammation, earlier recurrence, and less stable refraction. Copyright © 2015 Elsevier Inc. All rights reserved.

Spectral analysis software improves confidence in plant and soil water stable isotope analyses performed by isotope ratio infrared spectroscopy (IRIS).

PubMed

West, A G; Goldsmith, G R; Matimati, I; Dawson, T E

2011-08-30

Previous studies have demonstrated the potential for large errors to occur when analyzing waters containing organic contaminants using isotope ratio infrared spectroscopy (IRIS). In an attempt to address this problem, IRIS manufacturers now provide post-processing spectral analysis software capable of identifying samples with the types of spectral interference that compromises their stable isotope analysis. Here we report two independent tests of this post-processing spectral analysis software on two IRIS systems, OA-ICOS (Los Gatos Research Inc.) and WS-CRDS (Picarro Inc.). Following a similar methodology to a previous study, we cryogenically extracted plant leaf water and soil water and measured the δ(2)H and δ(18)O values of identical samples by isotope ratio mass spectrometry (IRMS) and IRIS. As an additional test, we analyzed plant stem waters and tap waters by IRMS and IRIS in an independent laboratory. For all tests we assumed that the IRMS value represented the "true" value against which we could compare the stable isotope results from the IRIS methods. Samples showing significant deviations from the IRMS value (>2σ) were considered to be contaminated and representative of spectral interference in the IRIS measurement. Over the two studies, 83% of plant species were considered contaminated on OA-ICOS and 58% on WS-CRDS. Post-analysis, spectra were analyzed using the manufacturer's spectral analysis software, in order to see if the software correctly identified contaminated samples. In our tests the software performed well, identifying all the samples with major errors. However, some false negatives indicate that user evaluation and testing of the software are necessary. Repeat sampling of plants showed considerable variation in the discrepancies between IRIS and IRMS. As such, we recommend that spectral analysis of IRIS data must be incorporated into standard post-processing routines. Furthermore, we suggest that the results from spectral analysis be included when reporting stable isotope data from IRIS. Copyright © 2011 John Wiley & Sons, Ltd.

S-Adenosylmethionine attenuates bile duct early warm ischemia reperfusion injury after rat liver transplantation.

PubMed

Tang, Yong; Chu, Hongpeng; Cao, Guojun; Du, Xiaolong; Min, Xiaobo; Wan, Chidan

2018-03-01

Warm ischemia reperfusion injury (IRI) plays a key role in biliary complication, which is a substantial vulnerability of liver transplantation. The early pathophysiological changes of IRI are characterized by an excessive inflammatory response. S-Adenosylmethionine (SAM) is an important metabolic intermediate that modulates inflammatory reactions; however, its role in bile duct warm IRI is not known. In this study, male rats were treated with or without SAM (170 μmol/kg body weight) after orthotopic autologous liver transplantation. The histopathological observations showed that bile duct injury in the IRI group was more serious than in the SAM group. The alanine aminotransferase (ALT), alkaline phosphatase (ALP) and direct bilirubin (DBIL) levels in the serum of the IRI group were significantly increased compared to the SAM group (P < .05). Simultaneously, SAM effectively improved the survival of the transplant recipients. Furthermore, the H 2 O 2 and malondialdehyde (MDA) of the IRI group were much higher compared to the SAM group (P < .05). The GSH/GSSG ratio in the SAM group was significantly increased by SAM treatment compared to the IRI group (P < .05). SAM administration significantly inhibited macrophage infiltration in liver and bile duct tissues, down-regulated TNF-α levels and up-regulated IL-10 expression in bile duct tissues compared to the IRI group (P < .05). The number of apoptotic biliary epithelial cells and caspase-3-positive cells in IRI rat livers were much higher compared to those in SAM-treated rats at 24 h after liver transplantation (P < .05). These data suggested that SAM protected bile ducts against warm IRI by suppressing oxidative stress, inflammatory reactions and apoptosis of biliary epithelial cells after liver transplantation.α. Copyright © 2018 Elsevier Ltd. All rights reserved.

Ice-binding proteins confer freezing tolerance in transgenic Arabidopsis thaliana.

PubMed

Bredow, Melissa; Vanderbeld, Barbara; Walker, Virginia K

2017-01-01

Lolium perenne is a freeze-tolerant perennial ryegrass capable of withstanding temperatures below -13 °C. Ice-binding proteins (IBPs) presumably help prevent damage associated with freezing by restricting the growth of ice crystals in the apoplast. We have investigated the expression, localization and in planta freezing protection capabilities of two L. perenne IBP isoforms, LpIRI2 and LpIRI3, as well as a processed IBP (LpAFP). One of these isoforms, LpIRI2, lacks a conventional signal peptide and was assumed to be a pseudogene. Nevertheless, both LpIRI2 and LpIRI3 transcripts were up-regulated following cold acclimation. LpIRI2 also demonstrated ice-binding activity when produced recombinantly in Escherichia coli. Both the LpIRI3 and LpIRI2 isoforms appeared to accumulate in the apoplast of transgenic Arabidopsis thaliana plants. In contrast, the fully processed isoform, LpAFP, remained intracellular. Transgenic plants expressing either LpIRI2 or LpIRI3 showed reduced ion leakage (12%-39%) after low-temperature treatments, and significantly improved freezing survival, while transgenic LpAFP-expressing lines did not confer substantial subzero protection. Freeze protection was further enhanced by with the introduction of more than one IBP isoform; ion leakage was reduced 26%-35% and 10% of plants survived temperatures as low as -8 °C. Our results demonstrate that apoplastic expression of multiple L. perenne IBP isoforms shows promise for providing protection to crops susceptible to freeze-induced damage. © 2016 The Authors. Plant Biotechnology Journal published by Society for Experimental Biology and The Association of Applied Biologists and John Wiley & Sons Ltd.

Cardiac-Specific SOCS3 Deletion Prevents In Vivo Myocardial Ischemia Reperfusion Injury through Sustained Activation of Cardioprotective Signaling Molecules.

PubMed

Nagata, Takanobu; Yasukawa, Hideo; Kyogoku, Sachiko; Oba, Toyoharu; Takahashi, Jinya; Nohara, Shoichiro; Minami, Tomoko; Mawatari, Kazutoshi; Sugi, Yusuke; Shimozono, Koutatsu; Pradervand, Sylvain; Hoshijima, Masahiko; Aoki, Hiroki; Fukumoto, Yoshihiro; Imaizumi, Tsutomu

2015-01-01

Myocardial ischemia reperfusion injury (IRI) adversely affects cardiac performance and the prognosis of patients with acute myocardial infarction. Although myocardial signal transducer and activator of transcription (STAT) 3 is potently cardioprotective during IRI, the inhibitory mechanism responsible for its activation is largely unknown. The present study aimed to investigate the role of the myocardial suppressor of cytokine signaling (SOCS)-3, an intrinsic negative feedback regulator of the Janus kinase (JAK)-STAT signaling pathway, in the development of myocardial IRI. Myocardial IRI was induced in mice by ligating the left anterior descending coronary artery for 1 h, followed by different reperfusion times. One hour after reperfusion, the rapid expression of JAK-STAT-activating cytokines was observed. We precisely evaluated the phosphorylation of cardioprotective signaling molecules and the expression of SOCS3 during IRI and then induced myocardial IRI in wild-type and cardiac-specific SOCS3 knockout mice (SOCS3-CKO). The activation of STAT3, AKT, and ERK1/2 rapidly peaked and promptly decreased during IRI. This decrease correlated with the induction of SOCS3 expression up to 24 h after IRI in wild-type mice. The infarct size 24 h after reperfusion was significantly reduced in SOCS3-CKO compared with wild-type mice. In SOCS3-CKO mice, STAT3, AKT, and ERK1/2 phosphorylation was sustained, myocardial apoptosis was prevented, and the expression of anti-apoptotic Bcl-2 family member myeloid cell leukemia-1 (Mcl-1) was augmented. Cardiac-specific SOCS3 deletion led to the sustained activation of cardioprotective signaling molecules including and prevented myocardial apoptosis and injury during IRI. Our findings suggest that SOCS3 may represent a key factor that exacerbates the development of myocardial IRI.

Cardiac-Specific SOCS3 Deletion Prevents In Vivo Myocardial Ischemia Reperfusion Injury through Sustained Activation of Cardioprotective Signaling Molecules

PubMed Central

Nagata, Takanobu; Yasukawa, Hideo; Kyogoku, Sachiko; Oba, Toyoharu; Takahashi, Jinya; Nohara, Shoichiro; Minami, Tomoko; Mawatari, Kazutoshi; Sugi, Yusuke; Shimozono, Koutatsu; Pradervand, Sylvain; Hoshijima, Masahiko; Aoki, Hiroki; Fukumoto, Yoshihiro; Imaizumi, Tsutomu

2015-01-01

Myocardial ischemia reperfusion injury (IRI) adversely affects cardiac performance and the prognosis of patients with acute myocardial infarction. Although myocardial signal transducer and activator of transcription (STAT) 3 is potently cardioprotective during IRI, the inhibitory mechanism responsible for its activation is largely unknown. The present study aimed to investigate the role of the myocardial suppressor of cytokine signaling (SOCS)-3, an intrinsic negative feedback regulator of the Janus kinase (JAK)-STAT signaling pathway, in the development of myocardial IRI. Myocardial IRI was induced in mice by ligating the left anterior descending coronary artery for 1 h, followed by different reperfusion times. One hour after reperfusion, the rapid expression of JAK-STAT–activating cytokines was observed. We precisely evaluated the phosphorylation of cardioprotective signaling molecules and the expression of SOCS3 during IRI and then induced myocardial IRI in wild-type and cardiac-specific SOCS3 knockout mice (SOCS3-CKO). The activation of STAT3, AKT, and ERK1/2 rapidly peaked and promptly decreased during IRI. This decrease correlated with the induction of SOCS3 expression up to 24 h after IRI in wild-type mice. The infarct size 24 h after reperfusion was significantly reduced in SOCS3-CKO compared with wild-type mice. In SOCS3-CKO mice, STAT3, AKT, and ERK1/2 phosphorylation was sustained, myocardial apoptosis was prevented, and the expression of anti-apoptotic Bcl-2 family member myeloid cell leukemia-1 (Mcl-1) was augmented. Cardiac-specific SOCS3 deletion led to the sustained activation of cardioprotective signaling molecules including and prevented myocardial apoptosis and injury during IRI. Our findings suggest that SOCS3 may represent a key factor that exacerbates the development of myocardial IRI. PMID:26010537

Customized humanoptics silicone iris prosthesis in eyes with posttraumatic iris loss: outcomes and complications.

PubMed

Spitzer, Martin Stephan; Nessmann, Anja; Wagner, Julia; Yoeruek, Efdal; Bartz-Schmidt, Karl Ulrich; Szurman, Peter; Szurman, Gesine B

2016-05-01

Posttraumatic partial or total iris defects often cause significant debilitating glare, photophobia, decreased vision and cosmetic problems. Currently, the best cosmetic results can be obtained with a customized silicone iris prosthesis. However, little is known about the functional results and the rate of complication if this type of iris prosthesis is implanted into severely traumatized eyes. The aim of this study is to analyse the functional and cosmetic outcomes as well as complications after Artificial Iris implantation. A consecutive series of 34 patients who received a customized silicone iris prosthesis after severe globe injury with total or sub-total iris loss was analysed retrospectively. Additionally, patients were interviewed regarding change in subjective complaints. Median follow-up was 24 months (range 12.0-48.8). Mean visual acuity prior to Artificial Iris implantation was 1.1 logMAR (range 0.3-2.6). Five patients (15%) had pre-existing glaucoma and eight patients (24%) had pre-existing hypotony. Visual acuity 12 months after surgery was 1.4 logMAR (range 0.2-2.6). Complications included newly diagnosed glaucoma in three eyes (9%) and hypotony in three eyes (9%), persisting intraocular inflammation or macular oedema in seven patients (21%), and corneal endothelial decompensation requiring corneal transplantation in six patients (18%). Patients' satisfaction increased by reducing glare and enhanced cosmetic appearance. The customized silicone iris prosthesis is an individualized treatment approach with appealing cosmetic results. Therefore, especially traumatized eyes with highly different posttraumatic conditions could benefit. However, in some patients, the implantation of this device may cause an increase of intraocular pressure, corneal endothelial decompensation or persisting inflammation. © 2016 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

Anterior Segment Optical Coherence Tomography Angiography for Identification of Iris Vasculature and Staging of Iris Neovascularization: A Pilot Study.

PubMed

Roberts, Philipp K; Goldstein, Debra A; Fawzi, Amani A

2017-08-01

Purpose/Aim of the study: To assess the ability of optical coherence tomographic angiography (OCTA) to visualize the normal iris vasculature as well as neovascularization of the iris (NVI). Study participants with healthy eyes, patients at risk of NVI development and patients with active or regressed NVI were consecutively included in this cross-sectional observational study. Imaging was performed using a commercially available OCTA system (RTVue- XR Avanti, Optovue Inc., Fremont, CA, USA). Abnormal iris vessels were graded on OCTA according to a modified clinical staging system and compared to slitlamp and gonioscopic findings. Fifty eyes of 26 study participants (16 healthy eyes, 19 eyes at risk, 15 eyes with different stages of NVI) were imaged using OCTA. In 11 out of 16 healthy eyes (69%) with light or moderately dark iris pigmentation, we observed physiological, radially aligned iris vasculature on OCTA imaging, which could not be visualized in five eyes (31%) with darkly pigmented irides. One eye in the "eyes at risk" group was diagnosed with NVI based on OCTA, which was not observed clinically. Fifteen eyes with clinically active or regressed NVI were imaged. Different stages of NVI could be differentiated by OCTA, corresponding well to an established clinical grading system. Four eyes showed regressed NVI by OCTA, not seen clinically, and were graded as a newly defined stage 4. This pilot clinical study showed that OCTA for imaging of the iris vasculature in health and disease is highly dependent on iris pigmentation. Fine, clinically invisible iris vessels can be visualized by OCTA in the very early stages as well as in the regressed stage of NVI.

Iris concavity, corneal biomechanics, and their correlations with ocular biometry in a cohort of 10- to 12-year-old UK school boys: baseline data.

PubMed

Shah, Ameet; Low, Sancy; Garway-Heath, David F; Foster, Paul J; Barton, Keith

2014-04-17

Pigment dispersion syndrome is associated with iris concavity. This study investigated the prevalence of iris concavity, defined as a measurement of ≤-0.1 mm, in a cohort of 10- to 12-year-old boys, and explored the relationship between iris curvature and anterior segment biometry. Associations with corneal biomechanical parameters also were explored. A cohort of school boys (n = 96) was recruited from a local school. Anterior segment optical coherence tomography (AS-OCT) was performed under accommodative and nonaccommodative conditions, and iris curvature quantified. Corneal hysteresis (CH) and corneal resistance factor (CRF) were measured with the ocular response analyzer (ORA). Noncontact axial biometry was performed using laser interferometry. The prevalence of iris concavity was 24% on distance fixation, increasing to 65% on accommodation. Variables significantly associated with nonaccommodating iris curvature were lens vault (P = 0.02) and mean keratometry (P = 0.02). For both variables acting jointly, R(2) = 0.30. Variables associated significantly with accommodating iris curvature were anterior chamber depth (P = 0.009), lens vault (P = 0.049), and mean scleral spur angle (P < 0.0001). For these three variables acting jointly, R(2) = 0.33. Significant association was found between CH and spur-to-spur distance (R(2) = 0.07, P = 0.025). Iris concavity was a common finding in this cohort and related to anterior segment biometric parameters. Further work is required to clarify whether anatomical differences exist between iris concavity seen in the adolescent eye and that found in adults with pigment dispersion syndrome. Copyright 2014 The Association for Research in Vision and Ophthalmology, Inc.

Relationship between iris surface features and angle width in Asian eyes.

PubMed

Sidhartha, Elizabeth; Nongpiur, Monisha Esther; Cheung, Carol Y; He, Mingguang; Wong, Tien Yin; Aung, Tin; Cheng, Ching-Yu

2014-10-23

To examine the associations between iris surface features with anterior chamber angle width in Asian eyes. In this prospective cross-sectional study, we recruited 600 subjects from a large population-based study, the Singapore Epidemiology of Eye Diseases (SEED) study. We obtained standardized digital slit-lamp iris photographs and graded the iris crypts (by number and size), furrows (by number and circumferential extent), and color (higher grade denoting darker iris). Vertical and horizontal cross-sections of anterior chamber were imaged using anterior segment optical coherence tomography. Angle opening distance (AOD), angle recess area (ARA), and trabecular-iris space area (TISA) were measured using customized software. Associations of the angle width with the iris surface features in the subject's right eyes were assessed using linear regression analysis. A total of 464 eyes of the 464 subjects (mean age: 57.5 ± 8.6 years) had complete and gradable data for crypts and color, and 423 eyes had gradable data for furrows. After adjustment for age, sex, ethnicity, pupil size, and corneal arcus, higher crypt grade was independently associated with wider AOD750 (β [change in angle width per grade higher] = 0.018, P = 0.023), ARA750 (β = 0.022, P = 0.049), and TISA750 (β = 0.011, P = 0.019), and darker iris was associated narrower ARA750 (β = -0.025, P = 0.044) and TISA750 (β = -0.013, P = 0.011). Iris surface features, assessed and measured from slit-lamp photographs, correlated well with anterior chamber angle width; irises with more crypts and lighter color were associated with wider angle. These findings may provide another imaging modality to assess angle closure risk based on iris surface features. Copyright 2014 The Association for Research in Vision and Ophthalmology, Inc.

Anterior Segment Optical Coherence Tomography Angiography for Identification of Iris Vasculature and Staging of Iris Neovascularization: A Pilot Study

PubMed Central

Roberts, Philipp K.; Goldstein, Debra A.; Fawzi, Amani A.

2017-01-01

Purpose/Aim of the study To assess the ability of optical coherence tomographic angiography (OCTA) to visualize the normal iris vasculature as well as neovascularization of the iris (NVI). Materials and Methods Study participants with healthy eyes, patients at risk of NVI development and patients with active or regressed NVI were consecutively included in this cross-sectional observational study. Imaging was performed using a commercially available OCTA system (RTVue- XR Avanti, Optovue Inc., Fremont, CA, USA). Abnormal iris vessels were graded on OCTA according to a modified clinical staging system and compared to slitlamp and gonioscopic findings. Results Fifty eyes of 26 study participants (16 healthy eyes, 19 eyes at risk, 15 eyes with different stages of NVI) were imaged using OCTA. In 11 out of 16 healthy eyes (69%) with light or moderately dark iris pigmentation, we observed physiological, radially aligned iris vasculature on OCTA imaging, which could not be visualized in five eyes (31%) with darkly pigmented irides. One eye in the “eyes at risk” group was diagnosed with NVI based on OCTA, which was not observed clinically. Fifteen eyes with clinically active or regressed NVI were imaged. Different stages of NVI could be differentiated by OCTA, corresponding well to an established clinical grading system. Four eyes showed regressed NVI by OCTA, not seen clinically, and were graded as a newly defined stage 4. Conclusions This pilot clinical study showed that OCTA for imaging of the iris vasculature in health and disease is highly dependent on iris pigmentation. Fine, clinically invisible iris vessels can be visualized by OCTA in the very early stages as well as in the regressed stage of NVI. PMID:28441067

Real-time image-guided nasogastric feeding tube placement: A case series using Kangaroo with IRIS Technology in an ICU.

PubMed

Mizzi, Anna; Cozzi, Silvano; Beretta, Luigi; Greco, Massimiliano; Braga, Marco

2017-05-01

Pulmonary misplacement during the blind insertion of enteral feeding tubes is frequent, particularly in ventilated and neurologically impaired patients. This is probably the first clinical study using the Kangaroo Feeding Tube with IRIS technology (IRIS) which incorporates a camera designed to provide anatomic landmark visualization during insertion. The study aim was to evaluate IRIS performance during bedside gastric placement. This is the first prospective study to collect data on the use of IRIS. Twenty consecutive unconscious patients requiring enteral nutrition were recruited at a single center. IRIS placement was considered complete when a clear image of the gastric mucosa appeared. Correct placement was confirmed using a contrast-enhanced abdominal X-ray. To evaluate the device performance over time, the camera was activated every other day up to 17 d postplacement. In 7 (35%) patients, the trachea was initially visualized, requiring a second placement attempt with the same tube. The IRIS camera allowed recognition of the gastric mucosa in 18 (90%) patients. The esophagogastric junction was identified in one patient, while in a second patient the quality of visualization was poor. Contrast-enhanced X-ray confirmed the gastric placement of IRIS in all patients. IRIS allowed identification of gastric mucosa in 14 (70%) patients 3 d after placement. Performance progressively declined with time (P = 0.006, chi-square for trend). IRIS placement could have spared X-ray confirmation in almost all patients and prevented misplacement into the airway in about one third. Visualization quality needs to be improved, particularly after the first week. Copyright © 2016 Elsevier Inc. All rights reserved.

Glufosinate-ammonium

Integrated Risk Information System (IRIS)

Integrated Risk Information System ( IRIS ) Chemical Assessment Summary U.S . Environmental Protection Agency National Center for Environmental Assessment This IRIS Summary has been removed from the IRIS database and is available for historical reference purposes . ( July 2016 ) Glufosinate - ammoni

Fomesafen

Integrated Risk Information System (IRIS)

Integrated Risk Information System ( IRIS ) Chemical Assessment Summary U.S . Environmental Protection Agency National Center for Environmental Assessment This IRIS Summary has been removed from the IRIS database and is available for historical reference purposes . ( July 2016 ) Fomesafen ; CASRN 72

Pirimiphos-methyl

Integrated Risk Information System (IRIS)

Integrated Risk Information System ( IRIS ) Chemical Assessment Summary U.S . Environmental Protection Agency National Center for Environmental Assessment This IRIS Summary has been removed from the IRIS database and is available for historical reference purposes . ( July 2016 ) Pirimiphos - methyl

Bromoxynil

Integrated Risk Information System (IRIS)

Integrated Risk Information System ( IRIS ) Chemical Assessment Summary U.S . Environmental Protection Agency National Center for Environmental Assessment This IRIS Summary has been removed from the IRIS database and is available for historical reference purposes . ( July 2016 ) Bromoxynil ; CASRN 1

Prometryn

Integrated Risk Information System (IRIS)

Integrated Risk Information System ( IRIS ) Chemical Assessment Summary U.S . Environmental Protection Agency National Center for Environmental Assessment This IRIS Summary has been removed from the IRIS database and is available for historical reference purposes . ( July 2016 ) Prometryn ; CASRN 72

Linuron

Integrated Risk Information System (IRIS)

Integrated Risk Information System ( IRIS ) Chemical Assessment Summary U.S . Environmental Protection Agency National Center for Environmental Assessment This IRIS Summary has been removed from the IRIS database and is available for historical reference purposes . ( July 2016 ) Linuron ; CASRN 330

Dimethoate

Integrated Risk Information System (IRIS)

Integrated Risk Information System ( IRIS ) Chemical Assessment Summary U.S . Environmental Protection Agency National Center for Environmental Assessment This IRIS Summary has been removed from the IRIS database and is available for historical reference purposes . ( July 2016 ) Dimethoate ; CASRN 6

Methidathion

Integrated Risk Information System (IRIS)

Integrated Risk Information System ( IRIS ) Chemical Assessment Summary U.S . Environmental Protection Agency National Center for Environmental Assessment This IRIS Summary has been removed from the IRIS database and is available for historical reference purposes . ( July 2016 ) Methidathion ; CASRN

Phenmedipham

Integrated Risk Information System (IRIS)

Integrated Risk Information System ( IRIS ) Chemical Assessment Summary U.S . Environmental Protection Agency National Center for Environmental Assessment This IRIS Summary has been removed from the IRIS database and is available for historical reference purposes . ( July 2016 ) Phenmedipham ; CASRN

Pendimethalin

Integrated Risk Information System (IRIS)

Integrated Risk Information System ( IRIS ) Chemical Assessment Summary U.S . Environmental Protection Agency National Center for Environmental Assessment This IRIS Summary has been removed from the IRIS database and is available for historical reference purposes . ( July 2016 ) Pendimethalin ; CASR

Chlorsulfuron

Integrated Risk Information System (IRIS)

Integrated Risk Information System ( IRIS ) Chemical Assessment Summary U.S . Environmental Protection Agency National Center for Environmental Assessment This IRIS Summary has been removed from the IRIS database and is available for historical reference purposes . ( July 2016 ) Chlorsulfuron ; CASR

Thiophanate-methyl

Integrated Risk Information System (IRIS)

Integrated Risk Information System ( IRIS ) Chemical Assessment Summary U.S . Environmental Protection Agency National Center for Environmental Assessment This IRIS Summary has been removed from the IRIS database and is available for historical reference purposes . ( July 2016 ) Thiophanate - methyl

Thiram

Integrated Risk Information System (IRIS)

Integrated Risk Information System ( IRIS ) Chemical Assessment Summary U.S . Environmental Protection Agency National Center for Environmental Assessment This IRIS Summary has been removed from the IRIS database and is available for historical reference purposes . ( July 2016 ) Thiram ; CASRN 137 -

Benefin

Integrated Risk Information System (IRIS)

Integrated Risk Information System ( IRIS ) Chemical Assessment Summary U.S . Environmental Protection Agency National Center for Environmental Assessment This IRIS Summary has been removed from the IRIS database and is available for historical reference purposes . ( July 2016 ) Benefin ; CASRN 1861

Cyhalothrin/Karate

Integrated Risk Information System (IRIS)

Integrated Risk Information System ( IRIS ) Chemical Assessment Summary U.S . Environmental Protection Agency National Center for Environmental Assessment This IRIS Summary has been removed from the IRIS database and is available for historical reference purposes . ( July 2016 ) Cyhalothrin / Karate

Triallate

Integrated Risk Information System (IRIS)

Integrated Risk Information System ( IRIS ) Chemical Assessment Summary U.S . Environmental Protection Agency National Center for Environmental Assessment This IRIS Summary has been removed from the IRIS database and is available for historical reference purposes . ( July 2016 ) Triallate ; CASRN 23

Propiconazole

Integrated Risk Information System (IRIS)

Integrated Risk Information System ( IRIS ) Chemical Assessment Summary U.S . Environmental Protection Agency National Center for Environmental Assessment This IRIS Summary has been removed from the IRIS database and is available for historical reference purposes . ( July 2016 ) Propiconazole ; CASR

Chlorimuron-ethyl

Integrated Risk Information System (IRIS)

Integrated Risk Information System ( IRIS ) Chemical Assessment Summary U.S . Environmental Protection Agency National Center for Environmental Assessment This IRIS Summary has been removed from the IRIS database and is available for historical reference purposes . ( July 2016 ) Chlorimuron - ethyl

Cypermethrin

Integrated Risk Information System (IRIS)

Integrated Risk Information System ( IRIS ) Chemical Assessment Summary U.S . Environmental Protection Agency National Center for Environmental Assessment This IRIS Summary has been removed from the IRIS database and is available for historical reference purposes . ( July 2016 ) Cypermethrin ; CASRN

Napropamide

Integrated Risk Information System (IRIS)

Integrated Risk Information System ( IRIS ) Chemical Assessment Summary U.S . Environmental Protection Agency National Center for Environmental Assessment This IRIS Summary has been removed from the IRIS database and is available for historical reference purposes . ( July 2016 ) Napropamide ; CASRN

Difenzoquat

Integrated Risk Information System (IRIS)

Integrated Risk Information System ( IRIS ) Chemical Assessment Summary U.S . Environmental Protection Agency National Center for Environmental Assessment This IRIS Summary has been removed from the IRIS database and is available for historical reference purposes . ( July 2016 ) Difenzoquat ; CASRN

Diphenylamine

Integrated Risk Information System (IRIS)

Integrated Risk Information System ( IRIS ) Chemical Assessment Summary U.S . Environmental Protection Agency National Center for Environmental Assessment This IRIS Summary has been removed from the IRIS database and is available for historical reference purposes . ( July 2016 ) Diphenylamine ; CASR

Harmony

Integrated Risk Information System (IRIS)

Integrated Risk Information System ( IRIS ) Chemical Assessment Summary U.S . Environmental Protection Agency National Center for Environmental Assessment This IRIS Summary has been removed from the IRIS database and is available for historical reference purposes . ( July 2016 ) Harmony ; CASRN 7927

Bidrin

Integrated Risk Information System (IRIS)

Integrated Risk Information System ( IRIS ) Chemical Assessment Summary U.S . Environmental Protection Agency National Center for Environmental Assessment This IRIS Summary has been removed from the IRIS database and is available for historical reference purposes . ( July 2016 ) Bidrin ; CASRN 141 -

Pursuit

Integrated Risk Information System (IRIS)

Integrated Risk Information System ( IRIS ) Chemical Assessment Summary U.S . Environmental Protection Agency National Center for Environmental Assessment This IRIS Summary has been removed from the IRIS database and is available for historical reference purposes . ( July 2016 ) Pursuit ; CASRN 8133

Imazalil

Integrated Risk Information System (IRIS)

Integrated Risk Information System ( IRIS ) Chemical Assessment Summary U.S . Environmental Protection Agency National Center for Environmental Assessment This IRIS Summary has been removed from the IRIS database and is available for historical reference purposes . ( July 2016 ) Imazalil ; CASRN 355

Vinclozolin

Integrated Risk Information System (IRIS)

Integrated Risk Information System ( IRIS ) Chemical Assessment Summary U.S . Environmental Protection Agency National Center for Environmental Assessment This IRIS Summary has been removed from the IRIS database and is available for historical reference purposes . ( July 2016 ) Vinclozolin ; CASRN

Chlorpropham

Integrated Risk Information System (IRIS)

Integrated Risk Information System ( IRIS ) Chemical Assessment Summary U.S . Environmental Protection Agency National Center for Environmental Assessment This IRIS Summary has been removed from the IRIS database and is available for historical reference purposes . ( July 2016 ) Chlorpropham ; CASRN

Bayleton

Integrated Risk Information System (IRIS)

Integrated Risk Information System ( IRIS ) Chemical Assessment Summary U.S . Environmental Protection Agency National Center for Environmental Assessment This IRIS Summary has been removed from the IRIS database and is available for historical reference purposes . ( July 2016 ) Bayleton ; CASRN 431

Propargite

Integrated Risk Information System (IRIS)

Integrated Risk Information System ( IRIS ) Chemical Assessment Summary U.S . Environmental Protection Agency National Center for Environmental Assessment This IRIS Summary has been removed from the IRIS database and is available for historical reference purposes . ( July 2016 ) Propargite ; CASRN 2

Oxyfluorfen

Integrated Risk Information System (IRIS)

Integrated Risk Information System ( IRIS ) Chemical Assessment Summary U.S . Environmental Protection Agency National Center for Environmental Assessment This IRIS Summary has been removed from the IRIS database and is available for historical reference purposes . ( July 2016 ) Oxyfluorfen ; CASRN

Amdro

Integrated Risk Information System (IRIS)

Integrated Risk Information System ( IRIS ) Chemical Assessment Summary U.S . Environmental Protection Agency National Center for Environmental Assessment This IRIS Summary has been removed from the IRIS database and is available for historical reference purposes . ( July 2016 ) Amdro ; CASRN 67485

Sethoxydim

Integrated Risk Information System (IRIS)

Integrated Risk Information System ( IRIS ) Chemical Assessment Summary U.S . Environmental Protection Agency National Center for Environmental Assessment This IRIS Summary has been removed from the IRIS database and is available for historical reference purposes . ( July 2016 ) Sethoxydim ; CASRN 7

Asulam

Integrated Risk Information System (IRIS)

Integrated Risk Information System ( IRIS ) Chemical Assessment Summary U.S . Environmental Protection Agency National Center for Environmental Assessment This IRIS Summary has been removed from the IRIS database and is available for historical reference purposes . ( July 2016 ) Asulam ; CASRN 3337

Norflurazon

Integrated Risk Information System (IRIS)

Integrated Risk Information System ( IRIS ) Chemical Assessment Summary U.S . Environmental Protection Agency National Center for Environmental Assessment This IRIS Summary has been removed from the IRIS database and is available for historical reference purposes . ( July 2016 ) Norflurazon ; CASRN

Dodine

Integrated Risk Information System (IRIS)

Integrated Risk Information System ( IRIS ) Chemical Assessment Summary U.S . Environmental Protection Agency National Center for Environmental Assessment This IRIS Summary has been removed from the IRIS database and is available for historical reference purposes . ( July 2016 ) Dodine ; CASRN 2439

Dimethipin

Integrated Risk Information System (IRIS)

Integrated Risk Information System ( IRIS ) Chemical Assessment Summary U.S . Environmental Protection Agency National Center for Environmental Assessment This IRIS Summary has been removed from the IRIS database and is available for historical reference purposes . ( July 2016 ) Dimethipin ; CASRN 5

Bromoxynil octanoate

Integrated Risk Information System (IRIS)

Integrated Risk Information System ( IRIS ) Chemical Assessment Summary U.S . Environmental Protection Agency National Center for Environmental Assessment This IRIS Summary has been removed from the IRIS database and is available for historical reference purposes . ( July 2016 ) Bromoxynil octanoate

Folpet

Integrated Risk Information System (IRIS)

Integrated Risk Information System ( IRIS ) Chemical Assessment Summary U.S . Environmental Protection Agency National Center for Environmental Assessment This IRIS Summary has been removed from the IRIS database and is available for historical reference purposes . ( July 2016 ) Folpet ; CASRN 133 -

Flurprimidol

Integrated Risk Information System (IRIS)

Integrated Risk Information System ( IRIS ) Chemical Assessment Summary U.S . Environmental Protection Agency National Center for Environmental Assessment This IRIS Summary has been removed from the IRIS database and is available for historical reference purposes . ( July 2016 ) Flurprimidol ; CASRN

Oryzalin

Integrated Risk Information System (IRIS)

Integrated Risk Information System ( IRIS ) Chemical Assessment Summary U.S . Environmental Protection Agency National Center for Environmental Assessment This IRIS Summary has been removed from the IRIS database and is available for historical reference purposes . ( July 2016 ) Oryzalin ; CASRN 190

Lactofen

Integrated Risk Information System (IRIS)

Integrated Risk Information System ( IRIS ) Chemical Assessment Summary U.S . Environmental Protection Agency National Center for Environmental Assessment This IRIS Summary has been removed from the IRIS database and is available for historical reference purposes . ( July 2016 ) Lactofen ; CASRN 775

Flutolanil

Integrated Risk Information System (IRIS)

Integrated Risk Information System ( IRIS ) Chemical Assessment Summary U.S . Environmental Protection Agency National Center for Environmental Assessment This IRIS Summary has been removed from the IRIS database and is available for historical reference purposes . ( July 2016 ) Flutolanil ; CASRN 6

Acephate

Integrated Risk Information System (IRIS)

Integrated Risk Information System ( IRIS ) Chemical Assessment Summary U.S . Environmental Protection Agency National Center for Environmental Assessment This IRIS Summary has been removed from the IRIS database and is available for historical reference purposes . ( July 2016 ) Acephate ; CASRN 305

IRIS and the National Research Council (NRC)

EPA Pesticide Factsheets

Since the 2011 National Academies’ National Research Council (NRC) review of the IRIS Program's assessment of Formaldehyde, EPA and NRC have had an ongoing relationship into the improvements of developing the IRIS Assessments.

Development of IR imaging system simulator

NASA Astrophysics Data System (ADS)

Xiang, Xinglang; He, Guojing; Dong, Weike; Dong, Lu

2017-02-01

To overcome the disadvantages of the tradition semi-physical simulation and injection simulation equipment in the performance evaluation of the infrared imaging system (IRIS), a low-cost and reconfigurable IRIS simulator, which can simulate the realistic physical process of infrared imaging, is proposed to test and evaluate the performance of the IRIS. According to the theoretical simulation framework and the theoretical models of the IRIS, the architecture of the IRIS simulator is constructed. The 3D scenes are generated and the infrared atmospheric transmission effects are simulated using OGRE technology in real-time on the computer. The physical effects of the IRIS are classified as the signal response characteristic, modulation transfer characteristic and noise characteristic, and they are simulated on the single-board signal processing platform based on the core processor FPGA in real-time using high-speed parallel computation method.

IRIS Toxicological Review of Cerium Oxide and Cerium ...

EPA Pesticide Factsheets

On September 29, 2009, the IRIS Summary and Toxicological Review of Cerium Oxide and Cerium Compounds was finalized and loaded onto the IRIS database. The Toxicological Review of Cerium Oxide and Cerium Compounds was reviewed internally by EPA, by other federal agencies and White House Offices, by expert external peer reviewers, and by the public. In the new IRIS process, introduced by the EPA Administrator, all written comments on IRIS assessments submitted by other federal agencies and White House Offices will be made publicly available. Accordingly, interagency comments and the interagency draft of the Cerium Oxide and Cerium Compounds IRIS assessment are posted on this site. The draft Toxicological Review of Cerium Oxide and Cerium Compounds provides scientific support and rationale for the hazard identification and dose-response assessment pertaining to chronic exposure to cerium oxide and cerium compounds.

Does Iris Change Over Time?

PubMed Central

Mehrotra, Hunny; Vatsa, Mayank; Singh, Richa; Majhi, Banshidhar

2013-01-01

Iris as a biometric identifier is assumed to be stable over a period of time. However, some researchers have observed that for long time lapse, the genuine match score distribution shifts towards the impostor score distribution and the performance of iris recognition reduces. The main purpose of this study is to determine if the shift in genuine scores can be attributed to aging or not. The experiments are performed on the two publicly available iris aging databases namely, ND-Iris-Template-Aging-2008–2010 and ND-TimeLapseIris-2012 using a commercial matcher, VeriEye. While existing results are correct about increase in false rejection over time, we observe that it is primarily due to the presence of other covariates such as blur, noise, occlusion, and pupil dilation. This claim is substantiated with quality score comparison of the gallery and probe pairs. PMID:24244305

Retrospective Evaluation of Topical Bimatoprost and Iris Pigmentation Change.

PubMed

Zaleski-Larsen, Lisa A; Ruth, Nadine H; Fabi, Sabrina G

2017-12-01

Topical bimatoprost is a topical prostaglandin analog originally used to treat glaucoma and more recently used to cosmetically induce hypertrichosis of the eyelashes. Iris pigmentation change has been noted in the treatment of glaucoma but has not been assessed with the cosmetic periorbital application of bimatoprost. To evaluate for iris pigmentation change with the long-term cosmetic use of topical bimatoprost. A retrospective chart review in a cosmetic dermatology practice of women (N = 50) who consistently purchased topical bimatoprost over an average of 4.59 years was compared with that of age-matched non-bimatoprost patients (N = 50). A blinded evaluator assessed each patient for iris pigmentary change. No iris pigmentation change was noted with the cutaneous application of bimatoprost. The cutaneous application of bimatoprost appears to be safe with minimal risk for iris pigmentation change.

Does iris change over time?

PubMed

Mehrotra, Hunny; Vatsa, Mayank; Singh, Richa; Majhi, Banshidhar

2013-01-01

Iris as a biometric identifier is assumed to be stable over a period of time. However, some researchers have observed that for long time lapse, the genuine match score distribution shifts towards the impostor score distribution and the performance of iris recognition reduces. The main purpose of this study is to determine if the shift in genuine scores can be attributed to aging or not. The experiments are performed on the two publicly available iris aging databases namely, ND-Iris-Template-Aging-2008-2010 and ND-TimeLapseIris-2012 using a commercial matcher, VeriEye. While existing results are correct about increase in false rejection over time, we observe that it is primarily due to the presence of other covariates such as blur, noise, occlusion, and pupil dilation. This claim is substantiated with quality score comparison of the gallery and probe pairs.

IRIS Toxicological Review of Tetrahydrofuran (THF) ...

EPA Pesticide Factsheets

EPA is releasing the draft report, Toxicological Review of Tetrahydrofuran, that was distributed to Federal agencies and White House Offices for comment during the Science Discussion step of the IRIS Assessment Development Process. Comments received from other Federal agencies and White House Offices are provided below with external peer review panel comments. EPA is undertaking an Integrated Risk Information System (IRIS) health assessment for tetrahydrofuran. IRIS is an EPA database containing Agency scientific positions on potential adverse human health effects that may result from chronic (or lifetime) exposure to chemicals in the environment. IRIS contains chemical-specific summaries of qualitative and quantitative health information in support of two steps of the risk assessment paradigm, i.e., hazard identification and dose-response evaluation. IRIS assessments are used in combination with specific situational exposure assessment information to evaluate potential public health risk associated with environmental contaminants.

Comparison with IRI-PLUS and IRI-2012-TEC values of GPS-TEC values

NASA Astrophysics Data System (ADS)

Atıcı, Ramazan; Saǧır, Selçuk

2016-07-01

This study presents a comparison with IRI-PLUS and IRI-2012 Total Electron Content (TEC) values of Total Electron Content (TEC) values obtained from Ankara station (39,7 N; 32,76 E) of Global Position System (GPS) of Turkey on equinox and solstice days of 2009 year. For all days, it is observed that GPS-TEC values are greater than IRI-2012-TEC values, while IRI-PLUS-TEC values are very close to GPS-TEC values. When GPS-TEC values for both equinoxes are compared, it is seen that TEC values on September equinox are greater than one on March equinox. However, it is observed that GPS-TEC values on June solstice are greater than one on December solstice. Also, the relationship between GPS-TEC values and geomagnetic indexes is investigated.

Heparin binding epidermal growth factor in renal ischaemia/reperfusion injury.

PubMed

Mulder, Gemma M; Nijboer, Willemijn N; Seelen, Marc A; Sandovici, Maria; Bos, Eelke M; Melenhorst, Wynand B W H; Trzpis, Monika; Kloosterhuis, Niels J; Visser, Lydia; Henning, Rob H; Leuvenink, Henri G D; Ploeg, Rutger J; Sunnarborg, Susan W; van Goor, Harry

2010-06-01

The epidermal growth factor (EGF) receptor and its ligands are crucially involved in the renal response to ischaemia. We studied the heparin binding-epidermal growth factor (HB-EGF), a major ligand for the EGF receptor, in experimental and human ischaemia/reperfusion injury (IRI). HB-EGF mRNA and protein expression was studied in rat kidneys and cultured human tubular (HK-2) cells that were subjected to IRI and in human donor kidneys during transplantation. The effect of EGF receptor inhibition was investigated in vivo and in vitro. Furthermore, urinary HB-EGF protein excretion was studied after renal transplantation. Finally, HB-EGF KO and WT mice were subjected to IRI to study the role of HB-EGF in renal injury. HB-EGF mRNA was significantly up-regulated in the early phase of IRI in rats, cells, and human donor biopsies. Treatment with PKI-166 reduces macrophage accumulation and interstitial alpha-SMA in the early phase of IRI in rats. In vitro, PKI-166 causes a marked reduction in HB-EGF-induced cellular proliferation. Urinary HB-EGF is increased after transplantation compared with control urines from healthy subjects. HB-EGF KO mice subjected to IRI revealed significantly less morphological damage after IRI, compared with WT mice. We conclude that IRI results in early induction of HB-EGF mRNA and protein in vivo and in vitro. Absence of HB-EGF and inhibition of the EGF receptor in the early phase of IRI has protective effects, suggesting a modulating role for HB-EGF.

Measurement of the temperature increase in the porcine cadaver iris during direct illumination by femtosecond laser pulses

NASA Astrophysics Data System (ADS)

Sun, Hui; Kurtz, Ronald M.; Juhasz, Tibor

2010-02-01

Multiple femtosecond lasers have now been cleared for use for ophthalmic surgery, including for creation of corneal flaps in LASIK surgery. Preliminary measurements indicated that during typical surgical use, 50-60% of laser energy may pass beyond the cornea with potential effects on the iris. To further evaluate iris laser exposure during femtosecond corneal surgery, we measured the temperature increase in porcine cadaver iris in situ during direct illumination by the iFS Advanced Femtoosecond Laser (AMO Inc. Santa Ana, CA) with an infrared thermal imaging camera. To replicate the illumination geometry of the eye during the surgery, an excised porcine cadaver iris was placed 1.5 mm from the flat glass contact lens. The temperature field was observed in twenty cadaver iris at laser pulse energy levels ranging from 1 to 2 μJ (corresponding approximately to surgical energies of 2 to 4 μJ per pulse). Temperature increases up to 2.3 °C (corresponding to 2 μJ per pulse and 24 second procedure time) were observed in the cadaver iris with little variation in temperature profiles between specimens for the same laser energy illumination. For laser pulse energy and procedure time characteristic to the iFS Advanced Femtoosecond Laser the temperature increase was measured to be 1.2 °C. Our studies suggest that the magnitude of iris heating that occurs during such femtosecond laser corneal surgery is small and does not present a safety hazard to the iris.

Modeling IrisCode and its variants as convex polyhedral cones and its security implications.

PubMed

Kong, Adams Wai-Kin

2013-03-01

IrisCode, developed by Daugman, in 1993, is the most influential iris recognition algorithm. A thorough understanding of IrisCode is essential, because over 100 million persons have been enrolled by this algorithm and many biometric personal identification and template protection methods have been developed based on IrisCode. This paper indicates that a template produced by IrisCode or its variants is a convex polyhedral cone in a hyperspace. Its central ray, being a rough representation of the original biometric signal, can be computed by a simple algorithm, which can often be implemented in one Matlab command line. The central ray is an expected ray and also an optimal ray of an objective function on a group of distributions. This algorithm is derived from geometric properties of a convex polyhedral cone but does not rely on any prior knowledge (e.g., iris images). The experimental results show that biometric templates, including iris and palmprint templates, produced by different recognition methods can be matched through the central rays in their convex polyhedral cones and that templates protected by a method extended from IrisCode can be broken into. These experimental results indicate that, without a thorough security analysis, convex polyhedral cone templates cannot be assumed secure. Additionally, the simplicity of the algorithm implies that even junior hackers without knowledge of advanced image processing and biometric databases can still break into protected templates and reveal relationships among templates produced by different recognition methods.

PROTECTIVE EFFECT OF IRIS GERMANICA L. IN Β-AMYLOID-INDUCED ANIMAL MODEL OF ALZHEIMER'S DISEASE.

PubMed

Borhani, Mona; Sharifzadeh, Mohammad; Farzaei, Mohammad Hosein; Narimani, Zahra; Sabbaghziarani, Fatemeh; Gholami, Mahdi; Rahimi, Roja

2017-01-01

Alzheimer's disease (AD) is the most common cause of dementia that is an irretrievable chronic neurodegenerative disease. In the current study, we have examined the therapeutic effects of Iris germanica extract on Amyloid β (Aβ) induced memory impairment. Wistar rats were divided into five groups of 8 per each. Groups were as followed: control group which were normal rats without induction of AD, Aβ group which received Aβ (50 ng/side), iris 100 group which received Aβ + Iris (100 mg/kg), iris 200 group which received Aβ + Iris (200 mg/kg), and iris 400 group which received Aβ + Iris (400 mg/kg). AD was established by intrahippocampal injection of 50 ng/μl/side Aβ1-42. The day after surgery, animals in treatment groups received different doses of the aqueous extract of Iris by gavage for 30 days. Morris water maze test (MWM) was performed to assess the effects of I. germanica on learning and memory of rats with Aβ induced AD. Data from MWM tests, including escape latency and traveled distance, demonstrated that I. germanica extract could markedly improve spatial memory in comparison to control. Moreover, the plant had a significantly better effect on the performance of AD rats in the probe test. I. germanica extract can successfully reverse spatial learning dysfunction in an experimental model of AD. Further neuro psyco-pharmacological studies are mandatory to reveal the mechanism of action of this natural remedy in the management of AD symptoms.

Technical note: quantitative measures of iris color using high resolution photographs.

PubMed

Edwards, Melissa; Gozdzik, Agnes; Ross, Kendra; Miles, Jon; Parra, Esteban J

2012-01-01

Our understanding of the genetic architecture of iris color is still limited. This is partly related to difficulties associated with obtaining quantitative measurements of eye color. Here we introduce a new automated method for measuring iris color using high resolution photographs. This method extracts color measurements in the CIE 1976 L*a*b* (CIELAB) color space from a 256 by 256 pixel square sampled from the 9:00 meridian of the iris. Color is defined across three dimensions: L* (the lightness coordinate), a* (the red-green coordinate), and b* (the blue-yellow coordinate). We applied this method to a sample of individuals of diverse ancestry (East Asian, European and South Asian) that was genotyped for the HERC2 rs12913832 polymorphism, which is strongly associated with blue eye color. We identified substantial variation in the CIELAB color space, not only in the European sample, but also in the East Asian and South Asian samples. As expected, rs12913832 was significantly associated with quantitative iris color measurements in subjects of European ancestry. However, this SNP was also strongly associated with iris color in the South Asian sample, although there were no participants with blue irides in this sample. The usefulness of this method is not restricted only to the study of iris pigmentation. High-resolution pictures of the iris will also make it possible to study the genetic variation involved in iris textural patterns, which show substantial heritability in human populations. Copyright © 2011 Wiley Periodicals, Inc.

Potentiating Tissue-Resident Type 2 Innate Lymphoid Cells by IL-33 to Prevent Renal Ischemia-Reperfusion Injury.

PubMed

Cao, Qi; Wang, Yiping; Niu, Zhiguo; Wang, Chengshi; Wang, Ruifeng; Zhang, Zhiqiang; Chen, Titi; Wang, Xin Maggie; Li, Qing; Lee, Vincent W S; Huang, Qingsong; Tan, Jing; Guo, Minghao; Wang, Yuan Min; Zheng, Guoping; Yu, Di; Alexander, Stephen I; Wang, Hui; Harris, David C H

2018-03-01

The IL-33-type 2 innate lymphoid cell (ILC2) axis has an important role in tissue homeostasis, inflammation, and wound healing. However, the relative importance of this innate immune pathway for immunotherapy against inflammation and tissue damage remains unclear. Here, we show that treatment with recombinant mouse IL-33 prevented renal structural and functional injury and reduced mortality in mice subjected to ischemia-reperfusion injury (IRI). Compared with control-treated IRI mice, IL-33-treated IRI mice had increased levels of IL-4 and IL-13 in serum and kidney and more ILC2, regulatory T cells (Tregs), and anti-inflammatory (M2) macrophages. Depletion of ILC2, but not Tregs, substantially abolished the protective effect of IL-33 on renal IRI. Adoptive transfer of ex vivo -expanded ILC2 prevented renal injury in mice subjected to IRI. This protective effect associated with induction of M2 macrophages in kidney and required ILC2 production of amphiregulin. Treatment of mice with IL-33 or ILC2 after IRI was also renoprotective. Furthermore, in a humanized mouse model of renal IRI, treatment with human IL-33 or transfer of ex vivo -expanded human ILC2 ameliorated renal IRI. This study has uncovered a major protective role of the IL-33-ILC2 axis in renal IRI that could be potentiated as a therapeutic strategy. Copyright © 2018 by the American Society of Nephrology.

An Objective Comparison of Cell Tracking Algorithms

PubMed Central

Ulman, Vladimír; Maška, Martin; Magnusson, Klas E. G.; Ronneberger, Olaf; Haubold, Carsten; Harder, Nathalie; Matula, Pavel; Matula, Petr; Svoboda, David; Radojevic, Miroslav; Smal, Ihor; Rohr, Karl; Jaldén, Joakim; Blau, Helen M.; Dzyubachyk, Oleh; Lelieveldt, Boudewijn; Xiao, Pengdong; Li, Yuexiang; Cho, Siu-Yeung; Dufour, Alexandre C.; Olivo-Marin, Jean-Christophe; Reyes-Aldasoro, Constantino C.; Solis-Lemus, Jose A.; Bensch, Robert; Brox, Thomas; Stegmaier, Johannes; Mikut, Ralf; Wolf, Steffen; Hamprecht, Fred. A.; Esteves, Tiago; Quelhas, Pedro; Demirel, Ömer; Malmström, Lars; Jug, Florian; Tomancak, Pavel; Meijering, Erik; Muñoz-Barrutia, Arrate; Kozubek, Michal; Ortiz-de-Solorzano, Carlos

2017-01-01

We present a combined report on the results of three editions of the Cell Tracking Challenge, an ongoing initiative aimed at promoting the development and objective evaluation of cell tracking algorithms. With twenty-one participating algorithms and a data repository consisting of thirteen datasets of various microscopy modalities, the challenge displays today’s state of the art in the field. We analyze the results using performance measures for segmentation and tracking that rank all participating methods. We also analyze the performance of all algorithms in terms of biological measures and their practical usability. Even though some methods score high in all technical aspects, not a single one obtains fully correct solutions. We show that methods that either take prior information into account using learning strategies or analyze cells in a global spatio-temporal video context perform better than other methods under the segmentation and tracking scenarios included in the challenge. PMID:29083403

Spatial Light Modulator Would Serve As Electronic Iris

NASA Technical Reports Server (NTRS)

Gutow, David A.

1991-01-01

In proposed technique for controlling brightness of image formed by lens, spatial light modulator serves as segmented, electronically variable aperture. Offers several advantages: spatial light modulator controlled remotely and responds faster than motorized iris or other remotely controlled mechanical iris. Unlike iris, modulator also configured so as not to vary depth of field appreciably. Unlike lead lanthanum zirconate titanate crystal, spatial light modulator does not require high voltage.

Risk factors and frequency of tuberculosis-associated immune reconstitution inflammatory syndrome among HIV/Tuberculosis co-infected patients in Southern India.

PubMed

Vignesh, Ramachandran; Swathirajan, Chinnambedu R; Solomon, Sunil S; Shankar, Esaki Muthu; Murugavel, Kailapuri G

2017-01-01

Immune reconstitution inflammatory syndrome (IRIS) continues to be a complication in HIV/tuberculosis (TB) co-infected patients initiating highly active antiretroviral therapy (HAART). The aim of this study was to evaluate the risk factors associated with developing IRIS to identify a possible biomarker to predict or diagnose IRIS in patients initiating HAART. A total of 175 HIV/TB co-infected patients initiating HAART were followed up longitudinally during September 2010 to May 2013 attending a HIV care clinic in Chennai. Patients were followed up longitudinally after HAART initiation and baseline demographic, laboratory parameters and treatment characteristics between patients with IRIS events and those without IRIS events were compared. Chi-square or Fisher's exact test for categorical variables and a Wilcoxon rank-sum test for continuous variables were performed using SPSS, version 12.0 software. Patients with IRIS had a significantly lower median baseline CD4+ T-cell count (P = 0.0039). There were no differences in terms of sex, CD4 T-cell %, plasma viral load, time interval between initiating ATT and HAART between the IRIS and non-IRIS patients. Low CD4+ T-cell count (<100 cells/μL) could be used as a marker to screen and monitor patients initiating HAART.

The infrared imaging spectrograph (IRIS) for TMT: overview of innovative science programs

NASA Astrophysics Data System (ADS)

Wright, Shelley A.; Larkin, James E.; Moore, Anna M.; Do, Tuan; Simard, Luc; Adamkovics, Maté; Armus, Lee; Barth, Aaron J.; Barton, Elizabeth; Boyce, Hope; Cooke, Jeffrey; Cote, Patrick; Davidge, Timothy; Ellerbroek, Brent; Ghez, Andrea M.; Liu, Michael C.; Lu, Jessica R.; Macintosh, Bruce A.; Mao, Shude; Marois, Christian; Schoeck, Matthias; Suzuki, Ryuji; Tan, Jonathan C.; Treu, Tommaso; Wang, Lianqi; Weiss, Jason

2014-07-01

IRIS (InfraRed Imaging Spectrograph) is a first light near-infrared diffraction limited imager and integral field spectrograph being designed for the future Thirty Meter Telescope (TMT). IRIS is optimized to perform astronomical studies across a significant fraction of cosmic time, from our Solar System to distant newly formed galaxies (Barton et al. [1]). We present a selection of the innovative science cases that are unique to IRIS in the era of upcoming space and ground-based telescopes. We focus on integral field spectroscopy of directly imaged exoplanet atmospheres, probing fundamental physics in the Galactic Center, measuring 104 to 1010 M supermassive black hole masses, resolved spectroscopy of young star-forming galaxies (1 < z < 5) and first light galaxies (6 < z < 12), and resolved spectroscopy of strong gravitational lensed sources to measure dark matter substructure. For each of these science cases we use the IRIS simulator (Wright et al. [2], Do et al. [3]) to explore IRIS capabilities. To highlight the unique IRIS capabilities, we also update the point and resolved source sensitivities for the integral field spectrograph (IFS) in all five broadband filters (Z, Y, J, H, K) for the finest spatial scale of 0.004" per spaxel. We briefly discuss future development plans for the data reduction pipeline and quicklook software for the IRIS instrument suite.

[Neuropathology of Natalizumab-Associated Progressive Multifocal Leukoencephalopathy].

PubMed

Kanda, Takashi

2015-07-01

The pathological findings of natalizumab-associated progressive multifocal leukoencephalopathy (PML) are reviewed. In addition to the classical pathology of PML including the presence of enlarged abnormal astrocytes, intranuclear inclusions mainly found within large swollen oligodendrocytes and abundant myelin-laden macrophages/microglia, massive perivascular and parenchymal mononuclear cell infiltration was observed. The latter pathologic picture is that of immune reconstitution inflammatory syndrome (IRIS), and most of these infiltrating cells are CD8-positive T cells. Because IRIS inevitably occurs after the cessation of natalizumab therapy due to the development of PML and subsequent plasma exchange, most of the published pathologic pictures of natalizumab-associated PML patients were a mixture of PML and PML-IRIS. PML-IRIS is also characterized by fewer oligodendroglial viral inclusions and fewer cells that are immunoreactive against anti-JCV antibodies. These findings suggest the effective removal of JCV after the return of normal immune-surveillance in the central nervous system, but clinicians should be aware that JCV elimination is not complete under the IRIS condition, and the immunosuppressive therapy against IRIS should be carefully performed. Mononuclear cell infiltration in natalizumab-associated PML-IRIS patients was much more prominent than that in HIV-associated PML-IRIS patients, reflecting the retained, even enhanced, systemic immunities in patients treated by natalizumab.

Effect of Γ-aminobutyric acid on kidney injury induced by renal ischemia-reperfusion in male and female rats: Gender-related difference.

PubMed

Vafapour, Marzieh; Nematbakhsh, Mehdi; Monajemi, Ramesh; Mazaheri, Safoora; Talebi, Ardeshir; Talebi, Nahid; Shirdavani, Soheyla

2015-01-01

The most important cause of kidney injury is renal ischemia/reperfusion injury (IRI), which is gender-related. This study was designed to investigate the protective role of Γ-aminobutyric acid (GABA (against IRI in male and female rats. Thirty-six female and male wistar rats were assigned to six experimental groups. The IRI was induced by clamping renal vessels for 45 min then was performed reperfusion for 24 h. The group sex posed to IRI were pretreated with GABA and were compared with the control groups. Serum levels of creatinine and blood urea nitrogen, kidney weight, and kidney tissue damage score increased in the IRI alone groups, (P < 0.05), while GABA decreased these parameters in female significantly (P < 0.05), but not in male rats. Uterus weight decreased significantly in female rats treated with GABA. Testis weight did not alter in male rats. Serum level of nitrite and kidney level of malondialdehyde (MDA) had no significant change in both female and male rats. Kidney level of nitrite increased significantly in female rats experienced IRI and serum level of MDA increased significantly in males that were exposed to IRI (P < 0.05). GABA could ameliorate kidney injury induced by renal IRI in a gender dependent manner.

IRIS Toxicological Review of Thallium and Compounds ...

EPA Pesticide Factsheets

Thallium compounds are used in the semiconductor industry, the manufacture of optic lenses and low-melting glass, low-temperature thermometers, alloys, electronic devices, mercury lamps, fireworks, and imitation germs, and clinically as an imaging agent in the diagnosis of certain tumors. EPA's assessment of noncancer health effects and carcinogenic potential of thallium compounds was last prepared and added to the IRIS database between 1988 and 1990. The IRIS program is preparing an assessment that will incorporate current health effects information available for thallium and compounds, and current risk assessment methods. The IRIS assessment for thallium compounds will consist of a Toxicological Review and IRIS Summary. The Toxicological Review is a critical review of the physiochemical and toxicokinetic properties of a chemical, and its toxicity in humans and experimental systems. The assessment will present reference values for the noncancer effects of thallium compounds (RfD and Rfc), and a cancer assessment. The Toxicological Review and IRIS Summary have been subject to Agency review, Interagency review, and external scientific peer review. The final product will reflect the Agency opinion on the overall toxicity of thallium and compounds. EPA is undertaking an Integrated Risk Information System (IRIS) health assessment for thallium and compounds. IRIS is an EPA database containing Agency scientific positions on potential adverse human health effec

Appropriate Objective Functions for Quantifying Iris Mechanical Properties Using Inverse Finite Element Modeling.

PubMed

Pant, Anup D; Dorairaj, Syril K; Amini, Rouzbeh

2018-07-01

Quantifying the mechanical properties of the iris is important, as it provides insight into the pathophysiology of glaucoma. Recent ex vivo studies have shown that the mechanical properties of the iris are different in glaucomatous eyes as compared to normal ones. Notwithstanding the importance of the ex vivo studies, such measurements are severely limited for diagnosis and preclude development of treatment strategies. With the advent of detailed imaging modalities, it is possible to determine the in vivo mechanical properties using inverse finite element (FE) modeling. An inverse modeling approach requires an appropriate objective function for reliable estimation of parameters. In the case of the iris, numerous measurements such as iris chord length (CL) and iris concavity (CV) are made routinely in clinical practice. In this study, we have evaluated five different objective functions chosen based on the iris biometrics (in the presence and absence of clinical measurement errors) to determine the appropriate criterion for inverse modeling. Our results showed that in the absence of experimental measurement error, a combination of iris CL and CV can be used as the objective function. However, with the addition of measurement errors, the objective functions that employ a large number of local displacement values provide more reliable outcomes.

The International Reference Ionosphere: Rawer's IRI and its status today

NASA Astrophysics Data System (ADS)

Bilitza, D.

2014-11-01

When the Committee on Space Research (COSPAR) initiated the International Reference Ionosphere (IRI) project in 1968 it wisely selected K. Rawer as its first Chairperson. With a solid footing and good contacts in both the ground-based and space-based ionospheric communities he was ideally suited to pull together colleagues and data from both communities to help build the first version of the IRI. He assembled a team of 20+ international ionospheric experts in the IRI Working Group and chaired and directed the group from 1968 to 1984. The working group has now grown to 63 members and the IRI model has undergone many revisions as new data became available and new modeling techniques were applied. This paper was presented during a special session of the Kleinheubach Tagung 2013 in honor of K. Rawer's 100th birthday. It will review the current status of the IRI model and project and the international recognition it has achieved. It is quite fitting that this year we not only celebrate K. Rawer's 100th birthday but also the exciting news that his favorite science endeavor, IRI, has been internationally recognized as an ISO (International Standardization Organization) standard. The IRI homepage is at http://irimodel.org.

Shape Adaptive, Robust Iris Feature Extraction from Noisy Iris Images

PubMed Central

Ghodrati, Hamed; Dehghani, Mohammad Javad; Danyali, Habibolah

2013-01-01

In the current iris recognition systems, noise removing step is only used to detect noisy parts of the iris region and features extracted from there will be excluded in matching step. Whereas depending on the filter structure used in feature extraction, the noisy parts may influence relevant features. To the best of our knowledge, the effect of noise factors on feature extraction has not been considered in the previous works. This paper investigates the effect of shape adaptive wavelet transform and shape adaptive Gabor-wavelet for feature extraction on the iris recognition performance. In addition, an effective noise-removing approach is proposed in this paper. The contribution is to detect eyelashes and reflections by calculating appropriate thresholds by a procedure called statistical decision making. The eyelids are segmented by parabolic Hough transform in normalized iris image to decrease computational burden through omitting rotation term. The iris is localized by an accurate and fast algorithm based on coarse-to-fine strategy. The principle of mask code generation is to assign the noisy bits in an iris code in order to exclude them in matching step is presented in details. An experimental result shows that by using the shape adaptive Gabor-wavelet technique there is an improvement on the accuracy of recognition rate. PMID:24696801

Shape adaptive, robust iris feature extraction from noisy iris images.

PubMed

Ghodrati, Hamed; Dehghani, Mohammad Javad; Danyali, Habibolah

2013-10-01

In the current iris recognition systems, noise removing step is only used to detect noisy parts of the iris region and features extracted from there will be excluded in matching step. Whereas depending on the filter structure used in feature extraction, the noisy parts may influence relevant features. To the best of our knowledge, the effect of noise factors on feature extraction has not been considered in the previous works. This paper investigates the effect of shape adaptive wavelet transform and shape adaptive Gabor-wavelet for feature extraction on the iris recognition performance. In addition, an effective noise-removing approach is proposed in this paper. The contribution is to detect eyelashes and reflections by calculating appropriate thresholds by a procedure called statistical decision making. The eyelids are segmented by parabolic Hough transform in normalized iris image to decrease computational burden through omitting rotation term. The iris is localized by an accurate and fast algorithm based on coarse-to-fine strategy. The principle of mask code generation is to assign the noisy bits in an iris code in order to exclude them in matching step is presented in details. An experimental result shows that by using the shape adaptive Gabor-wavelet technique there is an improvement on the accuracy of recognition rate.

Comparative analysis of classification based algorithms for diabetes diagnosis using iris images.

PubMed

Samant, Piyush; Agarwal, Ravinder

2018-01-01

Photo-diagnosis is always an intriguing area for the researchers, with the advancement of image processing and computer machine vision techniques it have become more reliable and popular in recent years. The objective of this paper is to study the change in the features of iris, particularly irregularities in the pigmentation of certain areas of the iris with respect to diabetic health of an individual. Apart from the point that iris recognition concentrates on the overall structure of the iris, diagnostic techniques emphasises the local variations in the particular area of iris. Pre-image processing techniques have been applied to extract iris and thereafter, region of interest from the extracted iris have been cropped out. In order to observe the changes in the tissue pigmentation of region of interest, statistical, texture textural and wavelet features have been extracted. At the end, a comparison of accuracies of five different classifiers has been presented to classify two subject groups of diabetic and non-diabetic. Best classification accuracy has been calculated as 89.66% by the random forest classifier. Results have been shown the effectiveness and diagnostic significance of the proposed methodology. Presented piece of work offers a novel systemic perspective of non-invasive and automatic diabetic diagnosis.

A benchmark for comparison of cell tracking algorithms

PubMed Central

Maška, Martin; Ulman, Vladimír; Svoboda, David; Matula, Pavel; Matula, Petr; Ederra, Cristina; Urbiola, Ainhoa; España, Tomás; Venkatesan, Subramanian; Balak, Deepak M.W.; Karas, Pavel; Bolcková, Tereza; Štreitová, Markéta; Carthel, Craig; Coraluppi, Stefano; Harder, Nathalie; Rohr, Karl; Magnusson, Klas E. G.; Jaldén, Joakim; Blau, Helen M.; Dzyubachyk, Oleh; Křížek, Pavel; Hagen, Guy M.; Pastor-Escuredo, David; Jimenez-Carretero, Daniel; Ledesma-Carbayo, Maria J.; Muñoz-Barrutia, Arrate; Meijering, Erik; Kozubek, Michal; Ortiz-de-Solorzano, Carlos

2014-01-01

Motivation: Automatic tracking of cells in multidimensional time-lapse fluorescence microscopy is an important task in many biomedical applications. A novel framework for objective evaluation of cell tracking algorithms has been established under the auspices of the IEEE International Symposium on Biomedical Imaging 2013 Cell Tracking Challenge. In this article, we present the logistics, datasets, methods and results of the challenge and lay down the principles for future uses of this benchmark. Results: The main contributions of the challenge include the creation of a comprehensive video dataset repository and the definition of objective measures for comparison and ranking of the algorithms. With this benchmark, six algorithms covering a variety of segmentation and tracking paradigms have been compared and ranked based on their performance on both synthetic and real datasets. Given the diversity of the datasets, we do not declare a single winner of the challenge. Instead, we present and discuss the results for each individual dataset separately. Availability and implementation: The challenge Web site (http://www.codesolorzano.com/celltrackingchallenge) provides access to the training and competition datasets, along with the ground truth of the training videos. It also provides access to Windows and Linux executable files of the evaluation software and most of the algorithms that competed in the challenge. Contact: codesolorzano@unav.es Supplementary information: Supplementary data are available at Bioinformatics online. PMID:24526711

Innate resistance of New Zealand paua to abalone viral ganglioneuritis.

PubMed

Corbeil, Serge; McColl, Kenneth A; Williams, Lynette M; Slater, Joanne; Crane, Mark St J

2017-06-01

The susceptibility of New Zealand paua (Haliotis iris) to infection by abalone herpesvirus (Haliotid herpesvirus 1; HaHV) and to the disease abalone viral ganglioneuritis (AVG) was determined. Infection challenges performed by intra-muscular injection and by immersion in infectious water containing HaHV demonstrated that New Zealand paua were highly resistant to infection by Haliotid herpesvirus 1 and were fully resistant to the disease AVG. Copyright © 2017 Elsevier Inc. All rights reserved.

IRIS Toxicological Review of Ethyl Tertiary Butyl Ether (Etbe) ...

EPA Pesticide Factsheets

The IRIS Toxicological Review of Ethyl Tertiary Butyl Ether (ETBE) was released for external peer review in June 2017. EPA’s Science Advisory Board’s (SAB) Chemical Assessment Advisory Committee (CAAC) will conduct a peer review of the scientific basis supporting the ETBE assessment and release a final report of their review. Information regarding the peer review can be found on the SAB website. EPA is conducting an Integrated Risk Information System (IRIS) health assessment for Ethyl Tertiary Butyl Ether (ETBE). The outcome of this project is a Toxicological Review and IRIS Summary for ETBE that will be entered into the IRIS database.

IRIS Toxicological Review of Benzo[a]pyrene (Final Report) ...

EPA Pesticide Factsheets

EPA has finalized the Integrated Risk Information System (IRIS) assessment of benzo[a]pyrene. This assessment addresses the potential cancer and noncancer human health effects from long-term exposure to benzo[a]pyrene. Now final, this assessment will update the toxicological information on benzo[a]pyrene posted in 1987. EPA’s program and regional offices may use this assessment to inform decisions to protect human health. EPA is undertaking an update of the Integrated Risk Information System (IRIS) health assessment for benzo[a]pyrene (BaP). The outcome of this project is an updated Toxicological Review and IRIS Summary for BaP that will be entered into the IRIS database.

IRIS Mission Operations Director's Colloquium

NASA Technical Reports Server (NTRS)

Carvalho, Robert; Mazmanian, Edward A.

2014-01-01

Pursuing the Mysteries of the Sun: The Interface Region Imaging Spectrograph (IRIS) Mission. Flight controllers from the IRIS mission will present their individual experiences on IRIS from development through the first year of flight. This will begin with a discussion of the unique nature of IRISs mission and science, and how it fits into NASA's fleet of solar observatories. Next will be a discussion of the critical roles Ames contributed in the mission including spacecraft and flight software development, ground system development, and training for launch. This will be followed by experiences from launch, early operations, ongoing operations, and unusual operations experiences. The presentation will close with IRIS science imagery and questions.

Multispectral iris recognition based on group selection and game theory

NASA Astrophysics Data System (ADS)

Ahmad, Foysal; Roy, Kaushik

2017-05-01

A commercially available iris recognition system uses only a narrow band of the near infrared spectrum (700-900 nm) while iris images captured in the wide range of 405 nm to 1550 nm offer potential benefits to enhance recognition performance of an iris biometric system. The novelty of this research is that a group selection algorithm based on coalition game theory is explored to select the best patch subsets. In this algorithm, patches are divided into several groups based on their maximum contribution in different groups. Shapley values are used to evaluate the contribution of patches in different groups. Results show that this group selection based iris recognition

From Revolution to Evolution: 21 Years of the IRIS Data Management Facility

NASA Astrophysics Data System (ADS)

Benson, R. B.; Ahern, T. K.; Trabant, C. M.; Casey, R.

2009-12-01

A revolution is defined as a "drastic and far-reaching change in the way of thinking and behaving", and this describes the effect that the IRIS Data Management System (DMS) has had in the framework of seismological research. The IRIS Data Management Center (DMC) prototype began operation at theUniversity of Texas at Austin in 1988 and has evolved to to a fully functioning facility at the University of Washington in Seattle. The focus of this submission is to share an historical timeline of events related to the DMC, a bit of scrap-booking perhaps, centered around the business of waveform data management conducted by IRIS and it's partners. We hope to illustrate how the successful philosophy of sharing unrestricted data, openly collaborating with a global network of networks, and partnering with computer and software industry vendors that have supported our community's academic research, has enabled generations of seismologists to both curate and continually "mine" the ever-growing 45 years of digital data currently stored in the perpetual archive located in Seattle, WA. At the time that the Loma Prieta Earthquake shook and burned San Francisco on October 17, 1989, there were only 3 stations which had dial-up modems enabling what then was considered "fast access" to waveform data delivery from them back to the DMC. This was considered the first test of the DMC, since waveform data were collected and distributed within days of this event. But this was only a foretelling of things to come, since the rates of archiving and distribution have continually grown to a current 1900+ stations and a 17,000+ channel count of real-time data streaming in and out of the DMC daily, totaling 50 Terabytes of data shipped in 2009 alone. We will attempt to summarize the important technological challenges, solutions, and growth of the DMC with the goal of illustrating that "if you build it, they will come", and how this could be useful to other organizations.

The IRIS Data Management Center: Enabling Access to Observational Time Series Spanning Decades

NASA Astrophysics Data System (ADS)

Ahern, T.; Benson, R.; Trabant, C.

2009-04-01

The Incorporated Research Institutions for Seismology (IRIS) is funded by the National Science Foundation (NSF) to operate the facilities to generate, archive, and distribute seismological data to research communities in the United States and internationally. The IRIS Data Management System (DMS) is responsible for the ingestion, archiving, curation and distribution of these data. The IRIS Data Management Center (DMC) manages data from more than 100 permanent seismic networks, hundreds of temporary seismic deployments as well as data from other geophysical observing networks such as magnetotelluric sensors, ocean bottom sensors, superconducting gravimeters, strainmeters, surface meteorological measurements, and in-situ atmospheric pressure measurements. The IRIS DMC has data from more than 20 different types of sensors. The IRIS DMC manages approximately 100 terabytes of primary observational data. These data are archived in multiple distributed storage systems that insure data availability independent of any single catastrophic failure. Storage systems include both RAID systems of greater than 100 terabytes as well as robotic tape robots of petabyte capacity. IRIS performs routine transcription of the data to new media and storage systems to insure the long-term viability of the scientific data. IRIS adheres to the OAIS Data Preservation Model in most cases. The IRIS data model requires the availability of metadata describing the characteristics and geographic location of sensors before data can be fully archived. IRIS works with the International Federation of Digital Seismographic Networks (FDSN) in the definition and evolution of the metadata. The metadata insures that the data remain useful to both current and future generations of earth scientists. Curation of the metadata and time series is one of the most important activities at the IRIS DMC. Data analysts and an automated quality assurance system monitor the quality of the incoming data. This insures data are of acceptably high quality. The formats and data structures used by the seismological community are esoteric. IRIS and its FDSN partners are developing web services that can transform the data holdings to structures that are more easily used by broader scientific communities. For instance, atmospheric scientists are interested in using global observations of microbarograph data but that community does not understand the methods of applying instrument corrections to the observations. Web processing services under development at IRIS will transform these data in a manner that allows direct use within such analysis tools as MATLAB® already in use by that community. By continuing to develop web-service based methods of data discovery and access, IRIS is enabling broader access to its data holdings. We currently support data discovery using many of the Open Geospatial Consortium (OGC) web mapping services. We are involved in portal technologies to support data discovery and distribution for all data from the EarthScope project. We are working with computer scientists at several universities including the University of Washington as part of a DataNet proposal and we intend to enhance metadata, further develop ontologies, develop a Registry Service to aid in the discovery of data sets and services, and in general improve the semantic interoperability of the data managed at the IRIS DMC. Finally IRIS has been identified as one of four scientific organizations that the External Research Division of Microsoft wants to work with in the development of web services and specifically with the development of a scientific workflow engine. More specific details of current and future developments at the IRIS DMC will be included in this presentation.

Fosetyl-al

Integrated Risk Information System (IRIS)

Integrated Risk Information System ( IRIS ) Chemical Assessment Summary U.S . Environmental Protection Agency National Center for Environmental Assessment This IRIS Summary has been removed from the IRIS database and is available for historical reference purposes . ( July 2016 ) Fosetyl - al ; CASRN

NuStar

Integrated Risk Information System (IRIS)

Integrated Risk Information System ( IRIS ) Chemical Assessment Summary U.S . Environmental Protection Agency National Center for Environmental Assessment This IRIS Summary has been removed from the IRIS database and is available for historical reference purposes . ( July 2016NuStar ; CASRN 85509 -

Merphos oxide

Integrated Risk Information System (IRIS)

Integrated Risk Information System ( IRIS ) Chemical Assessment Summary U.S . Environmental Protection Agency National Center for Environmental Assessment This IRIS Summary has been removed from the IRIS database and is available for historical reference purposes . ( July 2016 ) Merphos oxide ; CASR

78 FR 55290 - Approved Recovery Plan for the Dwarf Lake Iris

Federal Register 2010, 2011, 2012, 2013, 2014

2013-09-10

... plans. Additional efforts will focus on improving the baseline understanding of dwarf lake iris ecology... protection and management; (6) Improve understanding of baseline dwarf lake iris ecology; and (7) Review and...

Human tracking over camera networks: a review

NASA Astrophysics Data System (ADS)

Hou, Li; Wan, Wanggen; Hwang, Jenq-Neng; Muhammad, Rizwan; Yang, Mingyang; Han, Kang

2017-12-01

In recent years, automated human tracking over camera networks is getting essential for video surveillance. The tasks of tracking human over camera networks are not only inherently challenging due to changing human appearance, but also have enormous potentials for a wide range of practical applications, ranging from security surveillance to retail and health care. This review paper surveys the most widely used techniques and recent advances for human tracking over camera networks. Two important functional modules for the human tracking over camera networks are addressed, including human tracking within a camera and human tracking across non-overlapping cameras. The core techniques of human tracking within a camera are discussed based on two aspects, i.e., generative trackers and discriminative trackers. The core techniques of human tracking across non-overlapping cameras are then discussed based on the aspects of human re-identification, camera-link model-based tracking and graph model-based tracking. Our survey aims to address existing problems, challenges, and future research directions based on the analyses of the current progress made toward human tracking techniques over camera networks.

Multi-Beam Approach for Accelerating Alignment and Calibration of HyspIRI-Like Imaging Spectrometers

NASA Technical Reports Server (NTRS)

Eastwood, Michael L.; Green, Robert O.; Mouroulis, Pantazis; Hochberg, Eric B.; Hein, Randall C.; Kroll, Linley A.; Geier, Sven; Coles, James B.; Meehan, Riley

2012-01-01

A paper describes an optical stimulus that produces more consistent results, and can be automated for unattended, routine generation of data analysis products needed by the integration and testing team assembling a high-fidelity imaging spectrometer system. One key attribute of the system is an arrangement of pick-off mirrors that provides multiple input beams (five in this implementation) to simultaneously provide stimulus light to several field angles along the field of view of the sensor under test, allowing one data set to contain all the information that previously required five data sets to be separately collected. This stimulus can also be fed by quickly reconfigured sources that ultimately provide three data set types that would previously be collected separately using three different setups: Spectral Response Function (SRF), Cross-track Response Function (CRF), and Along-track Response Function (ARF), respectively. This method also lends itself to expansion of the number of field points if less interpolation across the field of view is desirable. An absolute minimum of three is required at the beginning stages of imaging spectrometer alignment.

IRIS TOXICOLOGICAL REVIEW AND SUMMARY ...

EPA Pesticide Factsheets

EPA's assessment of the noncancer health effects and carcinogenic potential of Beryllium was added to the IRIS database in 1998. The IRIS program is updating the IRIS assessment for Beryllium. This update will incorporate health effects information published since the last assessment was prepared as well as new risk assessment methods. The IRIS assessment for Beryllium will consist of an updated Toxicological Review and IRIS Summary. The Toxicological Review is a critical review of the physicochemical and toxicokinetic properties of the chemical and its toxicity in humans and experimental systems. The assessment will present reference values for noncancer effects of Beryllium (RfD and RfC) and a cancer assessment. The Toxicological Review and IRIS Summary will be subject to internal peer consultation, Agency and Interagency review, and external scientific peer review. The final products will constitute the Agency's opinion on the toxicity of Beryllium. Beryllium is a light alkaline earth metal used in metal alloys and in high-performance products in the metallurgical, aerospace, and nuclear industries. According to the Superfund database, beryllium is found in over 300 NPL sites

Three-dimensional orientation of iris in an ocular prosthesis using a customized scale.

PubMed

Gupta, Lokendra; Aparna, I N; Dhanasekar, B; Prabhu, Nayana; Malla, Nirjalla; Agarwal, Priyanka

2014-04-01

The success of an ocular prosthesis depends largely on the correct orientation of the iris disk. Various methods have been put forth to achieve this. This article emphasizes one such simplified method, wherein a customized scale has been used to orient the iris disk mediolaterally, superoinferiorly, and anteroposteriorly in an ocular prosthesis. A scleral wax pattern was fabricated. The customized scale was used to measure the dimension and orientation of the natural iris. These measurements were then transferred to the scleral wax pattern with the customized scale. An iris disk was fabricated using black crayon on the scleral wax pattern according to the measurements. The scleral wax pattern, including the iris disk, was then placed in the eye socket to verify its dimension and orientation. A prefabricated iris disk was modified according to the measured dimensions and transferred to the final scleral wax pattern. The transfer of these dimensions to the definitive prosthesis was achieved successfully, ultimately improving the patient's social and psychological well being. © 2013 by the American College of Prosthodontists.

Unified framework for automated iris segmentation using distantly acquired face images.

PubMed

Tan, Chun-Wei; Kumar, Ajay

2012-09-01

Remote human identification using iris biometrics has high civilian and surveillance applications and its success requires the development of robust segmentation algorithm to automatically extract the iris region. This paper presents a new iris segmentation framework which can robustly segment the iris images acquired using near infrared or visible illumination. The proposed approach exploits multiple higher order local pixel dependencies to robustly classify the eye region pixels into iris or noniris regions. Face and eye detection modules have been incorporated in the unified framework to automatically provide the localized eye region from facial image for iris segmentation. We develop robust postprocessing operations algorithm to effectively mitigate the noisy pixels caused by the misclassification. Experimental results presented in this paper suggest significant improvement in the average segmentation errors over the previously proposed approaches, i.e., 47.5%, 34.1%, and 32.6% on UBIRIS.v2, FRGC, and CASIA.v4 at-a-distance databases, respectively. The usefulness of the proposed approach is also ascertained from recognition experiments on three different publicly available databases.

Iris pigmentation as a quantitative trait: variation in populations of European, East Asian and South Asian ancestry and association with candidate gene polymorphisms.

PubMed

Edwards, Melissa; Cha, David; Krithika, S; Johnson, Monique; Cook, Gillian; Parra, Esteban J

2016-03-01

In this study, we present a new quantitative method to measure iris colour based on high-resolution photographs. We applied this method to analyse iris colour variation in a sample of individuals of East Asian, European and South Asian ancestry. We show that measuring iris colour using the coordinates of the CIELAB colour space uncovers a significant amount of variation that is not captured using conventional categorical classifications, such as 'brown', 'blue' or 'green'. We tested the association of a selected panel of polymorphisms with iris colour in each population group. Six markers showed significant associations with iris colour in the European sample, three in the South Asian sample and two in the East Asian sample. We also observed that the marker HERC2 rs12913832, which is the main determinant of 'blue' versus 'brown' iris colour in European populations, is also significantly associated with central heterochromia in the European sample. © 2015 The Authors. Pigment Cell & Melanoma Research Published by John Wiley & Sons Ltd.

Pupillary Reconstruction and Outcome after Artificial Iris Implantation.

PubMed

Mayer, Christian S; Reznicek, Lukas; Hoffmann, Andrea E

2016-05-01

Patients with iris defects suffer from severe visual impairment, especially increased glare sensitivity and cosmetic disturbances. This constitutes a great psychological strain for those patients. Until recently, possible treatment options were iris print contact lenses, sunglasses, and simple iris prostheses. The aim of this study was to investigate structural and functional outcome parameters and patient satisfaction after implantation of this new artificial iris prosthesis. Prospective case series investigating functional results and patient satisfaction after surgical iris reconstruction. Thirty-seven consecutive patients with traumatic iris defects presenting from 2011 through 2014 underwent pupillary reconstruction with a new artificial iris implant at the Department of Ophthalmology, Technical University Munich. The custom-made, flexible silicone iris prosthesis ArtificialIris (HumanOptics, Erlangen, Germany) used in this study is a novel and innovative device in the surgical treatment of iris defects. Patients were examined before and after iris reconstruction with the iris implant placed in the ciliary sulcus. Change of best-corrected visual acuity (BCVA), intraocular pressure (IOP), pupillary aperture, glare, contrast sensitivity, endothelial cell density, anterior chamber depth, anterior chamber angle, and patient satisfaction were assessed. Thirty-two eyes of 32 patients (mean age, 52.9±16.0 years) were included. After implantation and during follow-up, BCVA and IOP did not change significantly (BCVA, 0.77±0.62 logarithm of the minimum angle of resolution [logMAR] preoperatively vs. 0.68±0.64 logMAR 1 month postoperatively [P = 0.792]; IOP, 14.94±3.55 mmHg preoperatively vs. 17.72±5.88 mmHg 1 month postoperatively [P = 0.197]). The pupillary aperture was reduced significantly (42.11±20.1 mm(2) to 8.7±0.3 mm(2); P < 0.001). Contrast sensitivity increased significantly (0.80±0.51 to 0.93±0.49; P = 0.014). Endothelial cell count revealed a significant decrease postoperatively (1949±716 per 1 mm(2) to 1841±689 per 1 mm(2); P = 0.003). Anterior chamber depth (4.03±1.06 mm preoperatively vs. 4.29±0.70 mm postoperatively; P = 0.186) and angle (43.2±13.5° preoperatively vs. 40.5±10.8° postoperatively; P = 0.772) showed no significant differences. Subjective impairment through glare (9.12±1.62 preoperatively vs. 3.07±2.29 postoperatively; P < 0.001) and cosmetic disturbance (6.33±3.21 preoperatively vs. 1.58±0.86 postoperatively; P < 0.001) improved significantly. Patient satisfaction with the overall result was 8.91±1.51 of 10 points on an analog scale. The implantation of the artificial iris is a new and effective therapeutic option for the treatment of distinctive traumatic iris defects and results in an individual, aesthetically appealing, and good functional outcome in addition to high patient satisfaction. Copyright © 2016 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

Current progress on GSN data quality evaluation

NASA Astrophysics Data System (ADS)

Davis, J. P.; Gee, L. S.; Anderson, K. R.; Ahern, T. K.

2012-12-01

We discuss ongoing work to assess and improve the quality of data collected from instruments deployed at the 150+ stations of the Global Seismographic Network (GSN). The USGS and the IRIS Consortium are coordinating efforts to emphasize data quality following completion of the major installation phase of the GSN and recapitalization of the network's data acquisition systems, ancillary equipment and many of the secondary seismic sensors. We highlight here procedures adopted by the network's operators, the USGS' Albuquerque Seismological Laboratory (ASL) and UCSD's Project IDA, to ensure that the quality of the waveforms collected is maximized, that published metadata accurately reflect the instrument response of the data acquisitions systems, and that the data users are informed of the status of the GSN data quality. Additional details can be found at the GSN Quality webpage (www.iris.edu/hq/programs/gsn/quality). The GSN network operation teams meet frequently to share information and techniques. While custom software developed by each network operator to identify and track known problems remains important, recent efforts are providing new resources and tools to evaluate waveform quality, including analysis provided by the Lamont Waveform Quality Center (www.ldeo.columbia.edu/~ekstrom/Projects/WQC.html) and synthetic seismograms made available through Princeton University's Near Real Time Global Seismicity Portal ( http://global.shakemovie.princeton.edu/home.jsp ) and developments such as the IRIS DMS's MUSTANG and the ASL's Data Quality Analyzer. We conclude with the concept of station certification, a comprehensive overview of a station's performance that we have developed to communicate to data users the state of data- and metadata quality. As progress is made to verify the response and performance of existing systems as well as analysis of past calibration signals and waveform data, we will update information on the GSN web portals to apprise users of the condition of each GSN station's data.

Seasonal and Inter-Annual Patterns of Phytoplankton Community Structure in Monterey Bay, CA Derived from AVIRIS Data During the 2013-2015 HyspIRI Airborne Campaign

NASA Astrophysics Data System (ADS)

Palacios, S. L.; Thompson, D. R.; Kudela, R. M.; Negrey, K.; Guild, L. S.; Gao, B. C.; Green, R. O.; Torres-Perez, J. L.

2015-12-01

There is a need in the ocean color community to discriminate among phytoplankton groups within the bulk chlorophyll pool to understand ocean biodiversity, to track energy flow through ecosystems, and to identify and monitor for harmful algal blooms. Imaging spectrometer measurements enable use of sophisticated spectroscopic algorithms for applications such as differentiating among coral species, evaluating iron stress of phytoplankton, and discriminating phytoplankton taxa. These advanced algorithms rely on the fine scale, subtle spectral shape of the atmospherically corrected remote sensing reflectance (Rrs) spectrum of the ocean surface. As a consequence, these algorithms are sensitive to inaccuracies in the retrieved Rrs spectrum that may be related to the presence of nearby clouds, inadequate sensor calibration, low sensor signal-to-noise ratio, glint correction, and atmospheric correction. For the HyspIRI Airborne Campaign, flight planning considered optimal weather conditions to avoid flights with significant cloud/fog cover. Although best suited for terrestrial targets, the Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) has enough signal for some coastal chlorophyll algorithms and meets sufficient calibration requirements for most channels. However, the coastal marine environment has special atmospheric correction needs due to error that may be introduced by aerosols and terrestrially sourced atmospheric dust and riverine sediment plumes. For this HyspIRI campaign, careful attention has been given to the correction of AVIRIS imagery of the Monterey Bay to optimize ocean Rrs retrievals for use in estimating chlorophyll (OC3 algorithm) and phytoplankton functional type (PHYDOTax algorithm) data products. This new correction method has been applied to several image collection dates during two oceanographic seasons - upwelling and the warm, stratified oceanic period for 2013 and 2014. These two periods are dominated by either diatom blooms (occasionally toxic) or red tides. Results presented include chlorophyll and phytoplankton community structure and in-water validation data for these dates during these two seasons.

The GSN Data Quality Initiative

NASA Astrophysics Data System (ADS)

Davis, J. P.; Anderson, K. R.; Gee, L. S.

2010-12-01

The Global Seismographic Network (GSN) is undertaking a renewed effort to assess and assure data quality that builds upon completion of the major installation phase of the GSN and recent funding to recapitalize most of the network’s equipment including data acquisition systems, ancillary equipment and secondary sensors. We highlight here work by the network operators, the USGS’ Albuquerque Seismological Lab and UCSD’s Project IDA, to ensure that both the quality of the waveforms collected is maximized, that the published metadata accurately reflect the instrument response of the data acquisitions systems, and that data users are informed of the status of the GSN data quality. Procedures to evaluate waveform quality blend tools made available through the IRIS DMC’s Quality Analysis Control Kit (http://www.iris.washington.edu/QUACK/), analysis results provided by the Lamont Waveform Quality Center (www.ldeo.columbia.edu/~ekstrom/Projects/WQC.html), and custom software developed by each of the operators to identify and track known hardware failure modes. Each operator’s equipment upgrade schedule is updated periodically to address sensors identified as failing or problematic and for which replacements are available. Particular attention is also paid to monitoring the GPS clock signal to guarantee that the data are timed properly. Devices based on GPS technology unavailable when the GSN began 25 years ago are being integrated into operations to verify sensor orientations. Portable, broadband seismometers whose stable response can be verified in the laboratory are now co-located with GSN sensors during field visits to verify the existing GSN sensors’ sensitivity. Additional effort is being made to analyze past calibration signals and to check the system response functions of the secondary broadband sensors at GSN sites. The new generation of data acquisition systems will enable relative calibrations to be performed more frequently than was possible in the past. Additional details of this effort can be found at the GSN Quality webpage (www.iris.edu/hq/programs/gsn/quality).

S-Ethyl dipropylthiocarbamate (EPTC)

Integrated Risk Information System (IRIS)

Integrated Risk Information System ( IRIS ) Chemical Assessment Summary U.S . Environmental Protection Agency National Center for Environmental Assessment This IRIS Summary has been removed from the IRIS database and is available for historical reference purposes . ( July 2016 ) S - Ethyl dipropylth

IRIS Toxicological Review of Ammonia Noncancer Inhalation ...

EPA Pesticide Factsheets

EPA has finalized the Integrated Risk Information System (IRIS) Assessment of Ammonia (Noncancer Inhalation). This assessment addresses the potential noncancer human health effects from long-term inhalation exposure to ammonia. Now final, this assessment will update the current toxicological information on ammonia posted in 1991. EPA’s program and regional offices may use this assessment to inform decisions to protect human health. EPA completed the Integrated Risk Information System (IRIS) health assessment for ammonia. IRIS is an EPA database containing Agency scientific positions on potential adverse human health effects that may result from chronic (or lifetime) exposure to chemicals in the environment. IRIS contains chemical-specific summaries of qualitative and quantitative health information in support of two steps of the risk assessment paradigm, i.e., hazard identification and dose-response evaluation. IRIS assessments are used in combination with specific situational exposure assessment information to evaluate potential public health risk associated with environmental contaminants.

IRIS Toxicological Review of Libby Amphibole Asbestos ...

EPA Pesticide Factsheets

On August 25, 2011, the draft Toxicological Review of Libby Amphibole Asbestos and the charge to external peer reviewers were released for external peer review and public comment. The Toxicological Review and charge were reviewed internally by EPA and by other federal agencies and White House Offices before public release. In the new IRIS process (May 2009), introduced by the EPA Administrator, all written comments on IRIS assessments submitted by other federal agencies and White House Offices will be made publicly available. Accordingly, interagency comments and the interagency science consultation draft of the IRIS Toxicological Review of Libby Amphibole Asbestos and the charge to external peer reviewers are posted on this site. The project supports OSWER and Region 8 site clean-up and related risk management initiatives at this Superfund site. As with all IRIS assessments, the draft document will undergo agency review, OMB/interagency review and independent external peer review before being included on the IRIS data base.

Iris abscess as an unusual presentation of endogenous endophthalmitis in a patient with bacterial endocarditis.

PubMed

Ramonas, Krista M; Freilich, Benjamin D

2003-02-01

To report the clinical findings and management of a case of endogenous endophthalmitis in a patient with bacterial endocarditis presenting with a septic metastasis to the iris. Observational case report. Review of clinical findings and treatment. A 37-year-old intravenous drug user hospitalized with bacterial endocarditis secondary to methicillin-sensitive Staphylococcus aureus bacteremia presented with a painful red left eye, hypopyon, and iris abscess. Roth spots were noted in the fundus of the right eye. Aqueous culture was positive for methicillin-sensitive S aureus. The patient was treated with intravitreal, topical, and intravenous antibiotics. The hypopyon and iris abscess resolved within 2 weeks, and the patient achieved a final visual acuity of 20/25 in the left eye. Septic metastasis to the iris is a rare occurrence. To our knowledge this is the first reported case of an iris abscess secondary to bacterial endocarditis.

Multispectral diagnostic imaging of the iris in pigment dispersion syndrome.

PubMed

Roberts, Daniel K; Lukic, Ana; Yang, Yongyi; Wilensky, Jacob T; Wernick, Miles N

2012-08-01

To determine if wavelength selection with near infrared iris imaging may enhance iris transillumination defects (ITDs) in pigment dispersion syndrome. An experimental apparatus was used to acquire iris images in 6 African-American (AA) and 6 White patients with pigment dispersion syndrome. Light-emitting diode probes of 6 different spectral bands (700 to 950 nm) were used to project light into patients' eyes. Iris patterns were photographed, ITD regions of interest were outlined, and region of interest contrasts were calculated for each spectral band. Contrasts varied as a function of wavelength (P<0.0001) for both groups, but tended to be highest in the 700 to 800 nm range. Contrasts were higher in Whites than AAs at 700 nm but the opposite was found at 810 nm (P<0.001). Optimized near infrared iris imaging may be wavelength dependent. Ideal wavelength to image ITDs in more pigmented eyes may be slightly longer than for less pigmented eyes.

IRIS Toxicological Review of 1,4-Dioxane (with Inhalation ...

EPA Pesticide Factsheets

On September 9, 2011, the Toxicological Review of 1,4-Dioxane (inhalation) (External Review Draft) was posted for external peer review and public comment. Subsequently, the Toxicological Review and IRIS Summary were reviewed internally by EPA and by other federal agencies and Executive Office of the President before final public release. Based on the 2009 IRIS assessment development process, all written comments on IRIS assessments submitted by other federal agencies and the Executive Office of the President will be made publicly available. Accordingly, interagency comments with EPA's response and the interagency science discussion draft of the IRIS Toxicological Review of 1,4-dioxane (with inhalation update) and the draft IRIS Summary are posted on this site. The Toxicological Review of 1,4-dioxane provides scientific support and rationale for the hazard and dose-response assessment pertaining to chronic exposure to 1,4-dioxane.

[Use of computer technologies for studying the morphological characteristics of the iris color in anthropology].

PubMed

Dorofeeva, A A; Khrustalev, A V; Krylov, Iu V; Bocharov, D A; Negasheva, M A

2010-01-01

Digital images of the iris were received for study peculiarities of the iris color during the anthropological examination of 578 students aged 16-24 years. Simultaneously with the registration of the digital images, the visual assessment of the eye color was carried out using the traditional scale of Bunak, based on 12 ocular prostheses. Original software for automatic determination of the iris color based on 12 classes scale of Bunak was designed, and computer version of that scale was developed. The software proposed allows to conduct the determination of the iris color with high validity based on numerical evaluation; its application may reduce the bias due to subjective assessment and methodological divergences of the different researchers. The software designed for automatic determination of the iris color may help develop both theoretical and applied anthropology, it may be used in forensic and emergency medicine, sports medicine, medico-genetic counseling and professional selection.

Final Report from the External Peer Review of the IRIS ...

EPA Pesticide Factsheets

This document is the final report for the 2004 external peer review for the EPA IRIS Reassessment of the Inhalation Carcinogenicity of Naphthalene, prepared by the Office of Research and Development's National Center for Environmental Assessment (NCEA), for the Integrated Risk Information System (IRIS) Database. A panel of external peer reviewers met to discuss the IRIS report and their responses to the charge questions on July 30, 2004. This document contains the final written comments of the external peer reviewers. This document is the final report for the 2004 external peer review for the IRIS Reassessment of the Inhalation Carcinogenicity of Naphthalene, prepared by the U.S. Environmental Protection Agency (EPA), National Center for Environmental Assessment (NCEA), for the Integrated Risk Information System (IRIS). A panel of external peer reviewers met to discuss their responses to the charge questions on July 30, 2004. This document contains the final written comments of the external peer reviewers.

Fluid and structure coupling analysis of the interaction between aqueous humor and iris.

PubMed

Wang, Wenjia; Qian, Xiuqing; Song, Hongfang; Zhang, Mindi; Liu, Zhicheng

2016-12-28

Glaucoma is the primary cause of irreversible blindness worldwide associated with high intraocular pressure (IOP). Elevated intraocular pressure will affect the normal aqueous humor outflow, resulting in deformation of iris. However, the deformation ability of iris is closely related to its material properties. Meanwhile, the passive deformation of the iris aggravates the pupillary block and angle closure. The nature of the interaction mechanism of iris deformation and aqueous humor fluid flow has not been fully understood and has been somewhat a controversial issue. The purpose here was to study the effect of IOP, localization, and temperature on the flow of the aqueous humor and the deformation of iris interacted by aqueous humor fluid flow. Based on mechanisms of aqueous physiology and fluid dynamics, 3D model of anterior chamber (AC) was constructed with the human anatomical parameters as a reference. A 3D idealized standard geometry of anterior segment of human eye was performed. Enlarge the size of the idealization geometry model 5 times to create a simulation device by using 3D printing technology. In this paper, particle image velocimetry technology is applied to measure the characteristic of fluid outflow in different inlet velocity based on the device. Numerically calculations were made by using ANSYS 14.0 Finite Element Analysis. Compare of the velocity distributions to confirm the validity of the model. The fluid structure interaction (FSI) analysis was carried out in the valid geometry model to study the aqueous flow and iris change. In this paper, the validity of the model is verified through computation and comparison. The results indicated that changes of gravity direction of model significantly affected the fluid dynamics parameters and the temperature distribution in anterior chamber. Increased pressure and the vertical position increase the velocity of the aqueous humor fluid flow, with the value increased of 0.015 and 0.035 mm/s. The results act on the iris showed that, gravity direction from horizontal to vertical decrease the equivalent stress in the normal IOP model, while almost invariably in the high IOP model. With the increased of the iris elasticity modulus, the equivalent strain and the total deformation of iris is decreased. The maximal value of equivalent strain of iris in high IOP model is higher than that of in normal IOP model. The maximum deformation of iris is lower in the high IOP model than in the normal IOP model. The valid model of idealization geometry of human eye could be helpful to study the relationship between localization, iris deformation and IOP. So far the FSI analysis was carried out in that idealization geometry model of anterior segment to study aqueous flow and iris change.

Interactive target tracking for persistent wide-area surveillance

NASA Astrophysics Data System (ADS)

Ersoy, Ilker; Palaniappan, Kannappan; Seetharaman, Guna S.; Rao, Raghuveer M.

2012-06-01

Persistent aerial surveillance is an emerging technology that can provide continuous, wide-area coverage from an aircraft-based multiple-camera system. Tracking targets in these data sets is challenging for vision algorithms due to large data (several terabytes), very low frame rate, changing viewpoint, strong parallax and other imperfections due to registration and projection. Providing an interactive system for automated target tracking also has additional challenges that require online algorithms that are seamlessly integrated with interactive visualization tools to assist the user. We developed an algorithm that overcomes these challenges and demonstrated it on data obtained from a wide-area imaging platform.

Real-Time Radar-Based Tracking and State Estimation of Multiple Non-Conformant Aircraft

NASA Technical Reports Server (NTRS)

Cook, Brandon; Arnett, Timothy; Macmann, Owen; Kumar, Manish

2017-01-01

In this study, a novel solution for automated tracking of multiple unknown aircraft is proposed. Many current methods use transponders to self-report state information and augment track identification. While conformant aircraft typically report transponder information to alert surrounding aircraft of its state, vehicles may exist in the airspace that are non-compliant and need to be accurately tracked using alternative methods. In this study, a multi-agent tracking solution is presented that solely utilizes primary surveillance radar data to estimate aircraft state information. Main research challenges include state estimation, track management, data association, and establishing persistent track validity. In an effort to realize these challenges, techniques such as Maximum a Posteriori estimation, Kalman filtering, degree of membership data association, and Nearest Neighbor Spanning Tree clustering are implemented for this application.

The iris signal: blue periphery, tan collaret and freckles pattern - strong indicators for epidermal skin cancer in South-Eastern Europe.

PubMed

Grigore, M; Furtunescu, F; Minca, D; Costache, M; Garbe, C; Simionescu, O

2018-03-10

Eye and skin share the embryological origin. Both are established risk factors in epidermal skin cancer. There are few reports using iris colour classification scales, most of them analyse colour in general or are too complex to use in daily practice. To investigate which iris colour pattern is associated with epidermal skin cancer in a S-E European Caucasian population. A case-control study was conducted on 480 patients: 229 skin cancers patients and 251 controls (dermatological patients free of skin cancers) admitted in two medical clinics of Dermatology in Bucharest, between October 2011 and May 2014. High-resolution iris photographs were taken for each patient. Three parameters of the iris were analysed individually and in association patterns for each patient: periphery, collaret and freckles. The most frequent iris colour pattern associated with epidermal skin cancer was blue periphery with light brown collaret and freckles present. In terms of individual parameters, the strongest indicators for skin cancer patients were blue periphery and blue collaret. The results of this study sustain the hypothesis that blue periphery with light brown collaret and freckles iris pattern is a reliable phenotypic marker for epidermal skin cancer. The results of this study differ from previous reports in which skin cancer risk was associated with a homogeneous blue iris. We account these differences in the characteristics of the recruited patients (S-E European, skin type II and III). The assessment of iris colour patterns is an easy and inexpensive detection tool in skin cancer risk assessment. © 2018 European Academy of Dermatology and Venereology.

IRIS Toxicological Review of Benzo[a]pyrene (Public Comment Draft)

EPA Science Inventory

EPA is developing an Integrated Risk Information System (IRIS) assessment of benzo[a]pyrene and has released the draft assessment for public comment and external peer review. When final, the assessment will appear on the IRIS database.

IRIS Toxicological Review of Naphthalene (1998 Final)

EPA Science Inventory

EPA announced the release of the final report, Toxicological Review of Naphthalene: in support of the Integrated Risk Information System (IRIS). The updated Summary for Naphthalene and accompanying toxicological review have been added to the IRIS Database.

ARCoIRIS | CTIO

Science.gov Websites

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IRIS Toxicological Review of Phosgene (Final Report)

EPA Science Inventory

EPA announced the release of the final report, Toxicological Review of Phosgene: in support of the Integrated Risk Information System (IRIS). The updated Summary for Phosgene and accompanying toxicological review have been added to the IRIS Database.

AHMCT Intelligent Roadway Information System (IRIS) technical support and testing

DOT National Transportation Integrated Search

2011-12-31

This report documents the research project AHMCT IRIS Technical Support and Testing, : performed under contract 65A0275, Task ID 1777. It presents an overview of the Intelligent : Roadway Information System (IRIS), and its design and function. ...

AHMCT Intelligent Roadway Information System (IRIS) technical support and testing.

DOT National Transportation Integrated Search

2011-12-01

This report documents the research project AHMCT IRIS Technical Support and Testing, : performed under contract 65A0275, Task ID 1777. It presents an overview of the Intelligent : Roadway Information System (IRIS), and its design and function. ...

IRIS Toxicological Review of Acrolein (2003 Final)

EPA Science Inventory

EPA announced the release of the final report, Toxicological Review of Acrolein: in support of the Integrated Risk Information System (IRIS). The updated Summary for Acrolein and accompanying toxicological review have been added to the IRIS Database.

IRIS Toxicological Review of Chloroform (Final Report)

EPA Science Inventory

EPA is announcing the release of the final report, Toxicological Review of Chloroform: in support of the Integrated Risk Information System (IRIS). The updated Summary for Chloroform and accompanying Quickview have also been added to the IRIS Database.

ET-1 deletion from endothelial cells protects the kidney during the extension phase of ischemia/reperfusion injury

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

Arfian, Nur; Emoto, Noriaki, E-mail: emoto@med.kobe-u.ac.jp; Department of Clinical Pharmacy, Kobe Pharmaceutical University, Kobe

Highlights: Black-Right-Pointing-Pointer Ischemia/reperfusion injury (IRI) induced increased endothelin-1 (ET-1) expression. Black-Right-Pointing-Pointer IRI was accompanied by tubular injury and remodeling of renal arteries. Black-Right-Pointing-Pointer IRI increased oxidative stress and inflammation. Black-Right-Pointing-Pointer Genetic suppression of ET-1 in endothelial cells attenuates IRI in the kidney. Black-Right-Pointing-Pointer The mechanisms include the inhibition of oxidative stress and inflammation. -- Abstract: Background: The prognosis of patients after acute kidney injury (AKI) is poor and treatment is limited. AKI is mainly caused by renal ischemia/reperfusion injury (IRI). During the extension phase of IRI, endothelial damage may participate in ischemia and inflammation. Endothelin-1 (ET-1) which is mostly secretedmore » by endothelial cells is an important actor of IRI, particularly through its strong vasoconstrictive properties. We aimed to analyze the specific role of ET-1 from the endothelial cells in AKI. Methods: We used mice lacking ET-1 in the vascular endothelial cells (VEETKO). We induced IRI in VEETKO mice and wild type controls by clamping both kidneys for 30 min. Sham operated mice were used as controls. Mice were sacrificed one day after IRI in order to investigate the extension phase of IRI. Kidney function was assessed based on serum creatinine concentration. Levels of expression of ET-1, its receptor ET{sub A}, protein kinase C, eNOS, E-Cadherin and inflammation markers were evaluated by real time PCR or western blot. Tubular injury was scored on periodic acid Schiff stained kidney preparations. Lumen and wall area of small intrarenal arteries were measured on kidney slices stained for alpha smooth muscle cell actin. Oxidative stress, macrophage infiltration and cell proliferation was evaluated on slices stained for 8-hydroxy-2 Prime -deoxyguanosine, F4/80 and PCNA, respectively. Results: IRI induced kidney failure and increased ET-1 and ET{sub A} receptor expression. This was accompanied by tubular injury, wall thickening and reduction of lumen area/wall area ratio of small renal arteries, increased oxidative stress and inflammation. These parameters were attenuated in VEETKO mice. Conclusion: Our results suggest that suppression of ET-1 from the endothelial cells attenuates IRI kidney injury. Blocking ET-1 effects may represent a therapeutic strategy in the management of AKI.« less

Effective Solar Indices for Ionospheric Modeling: A Review and a Proposal for a Real-Time Regional IRI

NASA Astrophysics Data System (ADS)

Pignalberi, A.; Pezzopane, M.; Rizzi, R.; Galkin, I.

2018-01-01

The first part of this paper reviews methods using effective solar indices to update a background ionospheric model focusing on those employing the Kriging method to perform the spatial interpolation. Then, it proposes a method to update the International Reference Ionosphere (IRI) model through the assimilation of data collected by a European ionosonde network. The method, called International Reference Ionosphere UPdate (IRI UP), that can potentially operate in real time, is mathematically described and validated for the period 9-25 March 2015 (a time window including the well-known St. Patrick storm occurred on 17 March), using IRI and IRI Real Time Assimilative Model (IRTAM) models as the reference. It relies on foF2 and M(3000)F2 ionospheric characteristics, recorded routinely by a network of 12 European ionosonde stations, which are used to calculate for each station effective values of IRI indices IG_{12} and R_{12} (identified as IG_{{12{eff}}} and R_{{12{eff}}}); then, starting from this discrete dataset of values, two-dimensional (2D) maps of IG_{{12{eff}}} and R_{{12{eff}}} are generated through the universal Kriging method. Five variogram models are proposed and tested statistically to select the best performer for each effective index. Then, computed maps of IG_{{12{eff}}} and R_{{12{eff}}} are used in the IRI model to synthesize updated values of foF2 and hmF2. To evaluate the ability of the proposed method to reproduce rapid local changes that are common under disturbed conditions, quality metrics are calculated for two test stations whose measurements were not assimilated in IRI UP, Fairford (51.7°N, 1.5°W) and San Vito (40.6°N, 17.8°E), for IRI, IRI UP, and IRTAM models. The proposed method turns out to be very effective under highly disturbed conditions, with significant improvements of the foF2 representation and noticeable improvements of the hmF2 one. Important improvements have been verified also for quiet and moderately disturbed conditions. A visual analysis of foF2 and hmF2 maps highlights the ability of the IRI UP method to catch small-scale changes occurring under disturbed conditions which are not seen by IRI.

A potential protective effect of α-tocopherol on vascular complication in spinal cord reperfusion injury in rats

PubMed Central

2010-01-01

Background Paraplegia remains a potential complication of spinal cord ischemic reperfusion injury (IRI) in which oxidative stress induced cyclooxygenase activities may contribute to ischemic neuronal damage. Prolonged administration of vitamin E (α-TOL), as a potent biological antioxidant, may have a protective role in this oxidative inflammatory ischemic cascade to reduce the incidence of paraplegia. The present study was designed to evaluate the preventive value of α-TOL in IRI of spinal cord. Methods For this study, 50 male Sprague-Dawley rats were used and divided into five experimental groups (n = 10): Control group (C); α-TOL control group (CE) which received intramuscular (i.m.) α-TOL injections (600 mg/kg); Sham operated group (S), IRI rats were subjected to laparotomy and clamping of the aorta just above the bifurcation for 45 min, then the clamp was released for 48 hrs for reperfusion; and IRIE rats group, received 600 mg/kg of α-TOL i.m. twice weekly for 6 weeks, followed by induction of IRI similar to the IRI group. At the end of the experimental protocol; motor, sensory and placing/stepping reflex evaluation was done. Plasma nitrite/nitrate (NOx) was measured. Then animals' spinal cord lumbar segments were harvested and homogenized for measurement of the levels of prostaglandin E2 (PGE2), malondialdehyde (MDA) and advanced oxidation products (AOPP), while superoxide dismutase (SOD) and catalase (CAT) activity were evaluated. Results Induction of IRI in rats resulted in significant increases in plasma levels of nitrite/nitrate (p < 0.001) and spinal cord homogenate levels of PGE2, MDA, advanced oxidation protein products AOPP and SOD with significant reduction (p < 0.001) in CAT homogenate levels. Significant impairment of motor, sensory functions and placing/stepping reflex was observed with IRI induction in the spinal cord (p < 0.001). α-TOL administration in IRIE group significantly improved all the previously measured parameters compared with IRI group. Conclusions α-TOL administration significantly prevents the damage caused by spinal cord IRI in rats with subsequent recovery of both motor and sensory functions. Alpha-tocopherol improves the oxidative stress level with subsequent reduction of the incidence of neurological deficits due to spinal cord IRI conditions. PMID:20609232

Interferometric biosensing platform for multiplexed digital detection of viral pathogens and biomarkers

NASA Astrophysics Data System (ADS)

Daaboul, George

Label-free optical biosensors have been established as proven tools for monitoring specific biomolecular interactions. However, compact and robust embodiments of such instruments have yet to be introduced in order to provide sensitive, quantitative, and high-throughput biosensing for low-cost research and clinical applications. Here we present the interferometric reflectance-imaging sensor (IRIS). IRIS allows sensitive label free analysis using an inexpensive and durable multi-color LED illumination source on a silicon based surface. IRIS monitors biomolecular interaction through measurement of biomass addition to the sensor's surface. We demonstrate the capability of this system to dynamically monitor antigen---antibody interactions with a noise floor of 5.2 pg/mm 2 and DNA single mismatch detection under isothermal melting conditions in an array format. Ensemble detection of binding events using IRIS did not provide the sensitivity needed for detection of infectious disease and biomarkers at clinically relevant concentrations. Therefore, a new approach was adapted to the IRIS platform that allowed the detection and identification of individual nanoparticles on the sensor's surface. The new detection method was termed single-particle IRIS (SP-IRIS). We developed two detection modalities for SP-IRIS. The first modality is when the target is a nanoparticle such as a virus. We verified that SP-IRIS can accurately detect and size individual viral particles. Then we demonstrated that single nanoparticle counting and sizing methodology on SP-IRIS leads to a specific and sensitive virus sensor that can be multiplexed. Finally, we developed an assay for the detection of Ebola and Marburg. A detection limit of 3 x 103 PFU/ml was demonstrated for vesicular stomatitis virus (VSV) pseudotyped with Ebola or Marburg virus glycoprotein. We have demonstrated that virus detection can be done in human whole blood directly without the need for sample preparation. The second modality of SP-IRIS we developed was single molecule counting of biomarkers utilizing a sandwich assay with detection probes labeled with gold nanoparticles. We demonstrated the use of single molecule counting in a nucleic acid assay for melanoma biomarker detection. We showed that a single molecule counting assay can lead to detection limits in the attomolar range. The improved sensitivity of IRIS utilizing single nanoparticle detection holds promise for a simple and low-cost technology for rapid virus detection and multiplexed molecular screening for clinical applications.

Gonioscopy in primary angle closure glaucoma.

PubMed

Bruno, Christina A; Alward, Wallace L M

2002-06-01

Primary angle closure is a condition characterized by obstruction to aqueous humor outflow by the peripheral iris, and results in changes in the iridocorneal angle that are visible through gonioscopic examination. Gonioscopy in these eyes, however, can be difficult. This chapter discusses techniques that might help in the examination. These include beginning the examination with the inferior angle, methods to help in looking over the iris, cycloplegia, locating the corneal wedge, indentation, van Herick estimation, examining the other eye, and topical glycerin. Finally, there is a discussion about the pathology associated with the closed angle, with emphasis on the appearance of iris bombé, plateau iris, and the distinction between iris processes and peripheral anterior synechiae.

IRIS Toxicological Review of Hexahydro-1,3,5-Trinitro-1,3,5 ...

EPA Pesticide Factsheets

The IRIS Toxicological Review of Hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) was released for external peer review in September 2016. The EPA’s Science Advisory Board’s (SAB) Chemical Assessment Advisory Committee (CAAC) will conduct a peer review of the scientific basis supporting the RDX assessment and release a final report of their review. Information regarding the peer review can be found on the SAB website. EPA is undertaking an update of the Integrated Risk Information System (IRIS) health assessment for RDX. The outcome of this project is an updated Toxicological Review and IRIS Summary for RDX that will be entered into the IRIS database.

Iris recognition based on robust principal component analysis

NASA Astrophysics Data System (ADS)

Karn, Pradeep; He, Xiao Hai; Yang, Shuai; Wu, Xiao Hong

2014-11-01

Iris images acquired under different conditions often suffer from blur, occlusion due to eyelids and eyelashes, specular reflection, and other artifacts. Existing iris recognition systems do not perform well on these types of images. To overcome these problems, we propose an iris recognition method based on robust principal component analysis. The proposed method decomposes all training images into a low-rank matrix and a sparse error matrix, where the low-rank matrix is used for feature extraction. The sparsity concentration index approach is then applied to validate the recognition result. Experimental results using CASIA V4 and IIT Delhi V1iris image databases showed that the proposed method achieved competitive performances in both recognition accuracy and computational efficiency.

Robust visual tracking based on deep convolutional neural networks and kernelized correlation filters

NASA Astrophysics Data System (ADS)

Yang, Hua; Zhong, Donghong; Liu, Chenyi; Song, Kaiyou; Yin, Zhouping

2018-03-01

Object tracking is still a challenging problem in computer vision, as it entails learning an effective model to account for appearance changes caused by occlusion, out of view, plane rotation, scale change, and background clutter. This paper proposes a robust visual tracking algorithm called deep convolutional neural network (DCNNCT) to simultaneously address these challenges. The proposed DCNNCT algorithm utilizes a DCNN to extract the image feature of a tracked target, and the full range of information regarding each convolutional layer is used to express the image feature. Subsequently, the kernelized correlation filters (CF) in each convolutional layer are adaptively learned, the correlation response maps of that are combined to estimate the location of the tracked target. To avoid the case of tracking failure, an online random ferns classifier is employed to redetect the tracked target, and a dual-threshold scheme is used to obtain the final target location by comparing the tracking result with the detection result. Finally, the change in scale of the target is determined by building scale pyramids and training a CF. Extensive experiments demonstrate that the proposed algorithm is effective at tracking, especially when evaluated using an index called the overlap rate. The DCNNCT algorithm is also highly competitive in terms of robustness with respect to state-of-the-art trackers in various challenging scenarios.

Remedial Investigation Addendum Report Data Item A009. Volume 4: Appendices I-Z

DTIC Science & Technology

1993-12-01

Impatien~s capensis FACW Yellow Iris Iris pseudoacorus OBL Blueflag Iris Iris versicolor OBL 1 21 I NEW ENGLAND ENVIRONMENTAL, INC. Duckweed Lemna spp...small mammal community in the food web model. American woodcock (Scolopax minor ). This small bird is often j found in forested wetlands and forages...34Drinking Water and Health" Safe Drinking Water Committee, Washington, D.C. Thallium Thallium is a naturally occurring soft metal that is a minor

Ischemia-Reperfusion Injury and Volatile Anesthetics

PubMed Central

Erturk, Engin

2014-01-01

Ischemia-reperfusion injury (IRI) is induced as a result of reentry of the blood and oxygen to ischemic tissue. Antioxidant and some other drugs have protective effect on IRI. In many surgeries and clinical conditions IRI is counteract inevitable. Some anesthetic agents may have a protective role in this procedure. It is known that inhalational anesthetics possess protective effects against IRI. In this review the mechanism of preventive effects of volatile anesthetics and different ischemia-reperfusion models are discussed. PMID:24524079

Modulation of the neurological and vascular complications by grape seed extract in a rat model of spinal cord ischemia-reperfusion injury by downregulation of both osteopontin and cyclooxygenase-2.

PubMed

Sakr, Hussein F; Abbas, Amr M; Bin-Jaliah, Ismaeel

2016-07-01

In this study, we investigated the effects of grape seed extract (GSE) on the expression of osteopontin (OPN) and cyclooxygenase-2 (COX-2) in a rat model of spinal cord ischemia-reperfusion injury (SC-IRI). Fifty male rats were divided into 5 groups: control (CON); control + GSE (CON + GSE) (received GSE for 28 days); sham operated (Sham); IRI; and IRI + GSE. SC-IRI was induced by clamping the aorta just above the bifurcation for 45 min, and then the clamp was released for 48 h for reperfusion. IRI + GSE group received GSE for 28 days before SC-IRI. Sensory, motor, and placing/stepping reflex assessment was performed. Prostaglandin E2 (PGE2), thiobarbituric acid reactive substances (TBARs), and total antioxidant capacity (TAC) were measured in spinal cord homogenate. Immunohistochemical examination of the spinal cord for OPN and COX-2 were carried out. SC-IRI resulted in significant increase in plasma nitrite/nitrate level and spinal cord homogenate levels of TBARs and PGE2, and OPN and COX-2 expression with significant decrease in TAC. GSE improves the sensory and motor functions through decreasing OPN and COX-2 expression with reduction of oxidative stress parameters. We conclude a neuroprotective effect of GSE in SC-IRI through downregulating COX-2 and OPN expression plus its antioxidants effects.

Stem cells and their role in renal ischaemia reperfusion injury.

PubMed

Bagul, Atul; Frost, Jodie H; Drage, Martin

2013-01-01

Ischaemia-reperfusion injury (IRI) remains one of the leading causes of acute kidney injury (AKI). IRI is an underlying multifactorial pathophysiological process which affects the outcome in both native and transplanted patients. The high morbidity and mortality associated with IRI/AKI and disappointing results from current available clinical therapeutic approaches prompt further research. Stem cells (SC) are undifferentiated cells that can undergo both renewal and differentiation into one or more cell types which can possibly ameliorate IRI. To carry out a detailed literature analysis and construct a comprehensive literature review addressing the role of SC in AKI secondary to IRI. Evidence favouring the role of SC in renal IRI and evidence showing no benefits of SC in renal IRI are the two main aspects to be studied. The search strategy was based on an extensive search addressing MESH terms and free text terms. The majority of studies in the field of renal IRI and stem cell therapy show substantial benefits. Studies were mostly conducted in small animal models, thus underscoring the need for further pre-clinical studies in larger animal models, and results should be taken with caution. SC therapy may be promising though controversy exists in the exact mechanism. Thorough scientific exploration is required to assess mechanism, safety profile, reproducibility and methods to monitor administered SC. Copyright © 2012 S. Karger AG, Basel.

The Interface Region Imaging Spectrograph (IRIS) Small Explorer

NASA Astrophysics Data System (ADS)

de Pontieu, B.; Title, A. M.; Schryver, C. J.; Lemen, J. R.; Golub, L.; Kankelborg, C. C.; Carlsson, M.

2009-12-01

The Interface Region Imaging Spectrograph (IRIS) was recently selected as a small explorer mission by NASA. The primary goal of IRIS is to understand how the solar atmosphere is energized. The IRIS investigation combines advanced numerical modeling with a high resolution 20 cm UV imaging spectrograph that will obtain spectra covering temperatures from 4,500 to 10 MK in three wavelength ranges (1332-1358 Angstrom, 1390-1406 Angstrom and 2785-2835 Angstrom) and simultaneous images covering temperatures from 4,500 K to 65,000 K. IRIS will obtain UV spectra and images with high resolution in space (1/3 arcsec) and time (1s) focused on the chromosphere and transition region of the Sun, a complex dynamic interface region between the photosphere and corona. In this region, all but a few percent of the non-radiative energy leaving the Sun is converted into heat and radiation. IRIS fills a crucial gap in our ability to advance Sun-Earth connection studies by tracing the flow of energy and plasma through this foundation of the corona and heliosphere. The IRIS investigation is led by PI Alan Title (LMSAL) with major participation by the Harvard Smithsonian Astrophysical Observatory, Montana State University, NASA Ames Research Center, Stanford University and the University of Oslo (Norway). IRIS is scheduled for launch in late 2012, and will have a nominal two year mission lifetime.

IRIS TOXICOLOGICAL REVIEW AND SUMMARY ...

EPA Pesticide Factsheets

Trichloroacetic acid is a crystalline solid with sharp, pungent odor. It is used as a soil sterilizer; and as a laboratory intermediate or reagent in the synthesis of a variety of medicinal products and organic chemicals. Trichloroacetic acid is also used industrially as an etching and pickling agent for the surface treatment of metals and as a solvent in the plastics industry. Trichloroacetic acid can be formed as a combustion byproduct of organic compounds in the presence of chlorine. It is also formed as a disinfection byproduct during water chlorination. The existing IRIS entry was added to the IRIS data base between 1994 and 1996. No RfD was developed. The IRIS program is updating the IRIS assessment for Trichloroacetic Acid. This update will incorporate health effects information published since the last assessment was prepared as well as new risk assessment methods. The IRIS assessment for Trichloroacetic Acid will consist of a Toxicological Review and IRIS Summary. The Toxicological Review is a critical review of the physicochemical and toxicokinetic properties of the chemical and its toxicity in humans and experimental systems. The assessment will present reference value for noncancer effects of Trichloroacetic Acid (RfD) and a cancer assessment. The Toxicological Review and IRIS Summary will be subject to internal peer consultation, Agency review and external scientific peer review. The final products will constitute the Agency's opinion on the

Analysis of Four Automated Urinalysis Systems Compared to Reference Methods.

PubMed

Bartosova, Kamila; Kubicek, Zdenek; Franekova, Janka; Louzensky, Gustav; Lavrikova, Petra; Jabor, Antonin

2016-11-01

The aim of this study was to compare four automated urinalysis systems: the Iris iQ200 Sprint (Iris Diagnostics, U.S.A.) combined with the Arkray AUTION MAX AX 4030, Iris + AUTION, Arkray AU 4050 (Arkray Global Business, Inc., Japan), Dirui FUS 2000 (Dirui Industrial Co., P.R.C.), and Menarini sediMAX (Menarini, Italy). Urine concentrations of protein and glucose (Iris, Dirui) were compared using reference quantitative analysis on an Abbott Architect c16000. Leukocytes, erythrocytes, epithelia, and casts (Iris, Arkray, Diuri, Menarini) were compared to urine sediment under reference light microscopy, Leica DM2000 (Leica Microsystems GmbH, Germany) with calibrated FastRead plates (Biosigma S.r.l., Italy), using both native and stained preparations. Total protein and glucose levels were measured using the Iris + AUTION system with borderline trueness, while the Dirui analysis revealed worse performances for the protein and glucose measurements. True classifications of leukocytes and erythrocytes were above 85% and 72%, respectively. Kappa statistics revealed a nearly perfect evaluation of leukocytes for all tested systems; the erythrocyte evaluation was nearly perfect for the Iris, Dirui and Arkray analyzers and substantial for the Menarini analyzer. The epithelia identification was connected to high false negativity (above 15%) in the Iris, Arkray, and Menarini analyses. False-negative casts were above 70% for all tested systems. The use of automated urinalysis demonstrated some weaknesses and should be checked by experienced laboratory staff using light microscopy.

Vascular tumors of the iris in 45 patients: the 2009 Helen Keller Lecture.

PubMed

Shields, Jerry A; Bianciotto, Carlos; Kligman, Brad E; Shields, Carol L

2010-09-01

To report on a series of vascular tumors of the iris. Noncomparative case series. A retrospective medical record review of all patients with an iris vascular tumor was performed to identify the clinical features and develop a simple classification of these lesions. Included were demographics, clinical features, systemic associations, complications, management, and histopathology. There were 54 eyes in 45 patients with an iris vascular tumor. These were categorized as racemose hemangioma (41 eyes: 29 simple and 12 complex), cavernous hemangioma (3 eyes: 2 localized and 1 systemic), capillary hemangioma (1 eye, localized), varix (3 eyes, localized), and microhemangiomatosis (6 eyes, localized). The hemangiomas occurred in adults at a median age of 55 years, whereas capillary hemangioma occurred in infancy and cavernous hemangioma with systemic involvement occurred in a child. Of the 41 eyes with iris racemose hemangioma, none showed systemic involvement. Of all 54 eyes, transient hyphema was the main complication, found at some point in 30% or more of each affected eye except for iris capillary and racemose hemangioma. Surgical resection was necessary in 1 cavernous hemangioma and 1 varix. The remainder were managed with observation. There are now well-documented examples of iris racemose hemangioma, cavernous hemangioma, capillary hemangioma, varix, and microhemangiomatosis. Transient hyphema is the main complication. Observation is usually advised. Most are solitary lesions confined to the iris and some (cavernous hemangioma and microhemangiomatosis) can have important systemic associations.

Renal ischemia-reperfusion injury and adenosine 2A receptor-mediated tissue protection: the role of CD4+ T cells and IFN-gamma.

PubMed

Day, Yuan-Ji; Huang, Liping; Ye, Hong; Li, Li; Linden, Joel; Okusa, Mark D

2006-03-01

A(2A) adenosine receptor (A(2A)R)-expressing bone marrow (BM)-derived cells contribute to the renal protective effect of A(2A) agonists in renal ischemia-reperfusion injury (IRI). We performed IRI in mice lacking T and B cells to determine whether A(2A)R expressed in CD4+ cells mediate protection from IRI. Rag-1 knockout (KO) mice were protected in comparison to wild-type (WT) mice when subjected to IRI. ATL146e, a selective A(2A) agonist, did not confer additional protection. IFN-gamma is an important early signal in IRI and is thought to contribute to reperfusion injury. Because IFN-gamma is produced by kidney cells and T cells we performed IRI in BM chimeras in which the BM of WT mice was reconstituted with BM from IFN-gamma KO mice (IFN-gamma KO-->WT chimera). We observed marked reduction in IRI in comparison to WT-->WT chimeras providing additional indirect support for the role of T cells. To confirm the role of CD4+ A(2A)R in mediating protection from IRI, Rag-1 KO mice were subjected to ischemia-reperfusion. The protection observed in Rag-1 KO mice was reversed in Rag-1 KO mice that were adoptively transferred WT CD4+ cells (WT CD4+-->Rag-1 KO) or A(2A) KO CD4+ cells (A(2A) KO CD4+-->Rag-1 KO). ATL146e reduced injury in WT CD4+-->Rag-1 KO mice but not in A(2A) KO CD4+-->Rag-1 KO mice. Rag-1 KO mice reconstituted with CD4+ cells derived from IFN-gamma KO mice (IFN-gamma CD4+-->Rag-1 KO) were protected from IRI; ATL146e conferred no additional protection. These studies demonstrate that CD4+ IFN-gamma contributes to IRI and that A(2A) agonists mediate protection from IRI through action on CD4+ cells.

IRIS Toxicological Review of Decabromodiphenyl Ether (Final Report)

EPA Science Inventory

EPA announced the release of the final report, Toxicological Review of Decabromodiphenyl Ether: in support of the Integrated Risk Information System (IRIS). The updated Summary for Decabromodiphenyl Ether and accompanying toxicological review have been added to the IRIS Da...

4-(2-Methyl-4-chlorophenoxy) butyric acid (MCPB)

Integrated Risk Information System (IRIS)

Integrated Risk Information System ( IRIS ) Chemical Assessment Summary U.S . Environmental Protection Agency National Center for Environmental Assessment This IRIS Summary has been removed from the IRIS database and is available for historical reference purposes . ( July 2016 ) 4 - ( 2 - Methyl - 4

Inertial and inclinometer based profiler repeatability and accuracy using the IRI model : final report.

DOT National Transportation Integrated Search

2012-12-01

Oregon DOT is transitioning to use the International Roughness Index (IRI) for an incentive\\disincentive program for : pavement smoothness evaluation for newly paved roads. The IRI will typically be determined by contractors using inertial : profiler...

Replication of Structure Findings regarding the Interpersonal Reactivity Index.

ERIC Educational Resources Information Center

Carey, John C.; And Others

1988-01-01

Attempted to verify multidimensional nature and item composition of Interpersonal Reactivity Index (IRI) subscales through factor analysis. IRI responses from 365 female clinical dieticians and dietetic interns supported contention that IRI subscales measure four discernibly different empathy dimensions. (NB)

Vocabulary Questions on Informal Reading Inventories.

ERIC Educational Resources Information Center

Duffelmeyer, Fredrick A.; And Others

1989-01-01

Examines the utility of informal reading inventories (IRI) and acknowledges four limitations of the research. Indicates that no validity-enhancing measures were implemented in conjunction with the three IRIs analyzed. Suggests that IRI vocabulary questions do not appear to be useful. (MG)

An object tracking method based on guided filter for night fusion image

NASA Astrophysics Data System (ADS)

Qian, Xiaoyan; Wang, Yuedong; Han, Lei

2016-01-01

Online object tracking is a challenging problem as it entails learning an effective model to account for appearance change caused by intrinsic and extrinsic factors. In this paper, we propose a novel online object tracking with guided image filter for accurate and robust night fusion image tracking. Firstly, frame difference is applied to produce the coarse target, which helps to generate observation models. Under the restriction of these models and local source image, guided filter generates sufficient and accurate foreground target. Then accurate boundaries of the target can be extracted from detection results. Finally timely updating for observation models help to avoid tracking shift. Both qualitative and quantitative evaluations on challenging image sequences demonstrate that the proposed tracking algorithm performs favorably against several state-of-art methods.

IRIS Arrays: Observing Wavefields at Multiple Scales and Frequencies

NASA Astrophysics Data System (ADS)

Sumy, D. F.; Woodward, R.; Frassetto, A.

2014-12-01

The Incorporated Research Institutions for Seismology (IRIS) provides instruments for creating and operating seismic arrays at a wide range of scales. As an example, for over thirty years the IRIS PASSCAL program has provided instruments to individual Principal Investigators to deploy arrays of all shapes and sizes on every continent. These arrays have ranged from just a few sensors to hundreds or even thousands of sensors, covering areas with dimensions of meters to thousands of kilometers. IRIS also operates arrays directly, such as the USArray Transportable Array (TA) as part of the EarthScope program. Since 2004, the TA has rolled across North America, at any given time spanning a swath of approximately 800 km by 2,500 km, and thus far sampling 2% of the Earth's surface. This achievement includes all of the lower-48 U.S., southernmost Canada, and now parts of Alaska. IRIS has also facilitated specialized arrays in polar environments and on the seafloor. In all cases, the data from these arrays are freely available to the scientific community. As the community of scientists who use IRIS facilities and data look to the future they have identified a clear need for new array capabilities. In particular, as part of its Wavefields Initiative, IRIS is exploring new technologies that can enable large, dense array deployments to record unaliased wavefields at a wide range of frequencies. Large-scale arrays might utilize multiple sensor technologies to best achieve observing objectives and optimize equipment and logistical costs. Improvements in packaging and power systems can provide equipment with reduced size, weight, and power that will reduce logistical constraints for large experiments, and can make a critical difference for deployments in harsh environments or other situations where rapid deployment is required. We will review the range of existing IRIS array capabilities with an overview of previous and current deployments and examples of data and results. We will review existing IRIS projects that explore new array capabilities and highlight future directions for IRIS instrumentation facilities.

Honokiol protects against renal ischemia/reperfusion injury via the suppression of oxidative stress, iNOS, inflammation and STAT3 in rats.

PubMed

Yu, Yongwu; Li, Mingxv; Su, Ning; Zhang, Zhiyong; Zhao, Haidan; Yu, Hai; Xu, Yingluan

2016-02-01

Honokiol is the predominant active ingredient in the commonly used traditional Chinese medicine, Magnolia, which has been confirmed in previous studies to exhibit anti-oxidation, antimicrobial, antitumor and other pharmacological effects. However, its effects on renal ischemia/reperfusion injury (IRI) remain to be elucidated. The present study aimed to examine the effects of honokiol on renal IRI, and to investigate its potential protective mechanisms in the heart. Male adult Wistar albino rats were induced into a renal IRI model. Subsequently, the levels of serum creatinine, blood urea nitrogen (BUN), alanine aminotransferase (ALT), aspartate aminotransferase (AST) and alkaline phosphatase (ALP), and the levels of serum nitrite and the kidney nitrite were examined in the IRI group. The levels of oxidative stress, inducible nitric oxide synthase (iNOS), inflammatory factors and caspase-3 were evaluated using a series of commercially available kits. The levels of phosphorylated signal transducer and activator of transcription 3 (p-STAT3) and the protein expression levels of STAT3 were determined using western blotting. Pretreatment with honokiol significantly reduced the levels of serum creatinine, BUN, ALT, AST and ALP, and the level of nitrite in the kidney of the IRI group, compared with the control group. The levels of malondialdehyde, the activity of myeloperoxidase, and the gene expression and activity of iNOS were reduced in the IRI rats, compared with the sham-operated rats, whereas the levels of superoxide dismutase and catalase were increased following treatment with honokiol in the IRI rats. In addition, the expression levels of tumor necrosis factor-α and interleukin-6 in the IRI rats were increased by honokiol. Treatment with honokiol suppressed the protein expression levels of p-STAT3 and caspase-3 in the IRI rats. These findings indicated that honokiol protects against renal IRI via the suppression of oxidative stress, iNOS, inflammation and STAT3 in the rat.

Pharmacokinetic and pharmacogenetic markers of irinotecan toxicity.

PubMed

Hahn, Roberta Zilles; Antunes, Marina Venzon; Verza, Simone Gasparin; Perassolo, Magda Susana; Suyenaga, Edna Sayuri; Schwartsmann, Gilberto; Linden, Rafael

2018-06-22

Irinotecan (IRI) is a widely used chemotherapeutic drug, mostly used for first-line treatment of colorectal and pancreatic cancer. IRI doses are usually established based on patient's body surface area, an approach associated with large inter-individual variability in drug exposure and high incidence of severe toxicity. Toxic and therapeutic effects of IRI are also due to its active metabolite SN-38, reported to be up to 100 times more cytotoxic than IRI. SN-38 is detoxified by the formation of SN-38 glucuronide, through UGT1A1. Genetic polymorphisms in the UGT1A1 gene are associated to higher exposures to SN-38 and severe toxicity. Pharmacokinetic models to describe IRI and SN-38 kinetic profiles are available, with few studies exploring pharmacokinetic and pharmacogenetic-based dose individualization. The aim of this manuscript is to review the available evidence supporting pharmacogenetic and pharmacokinetic dose individualization of IRI in order to reduce the occurrence of severe toxicity during cancer treatment. The PubMed database was searched, considering papers published in the period from 1995-2017, using the keywords irinotecan, pharmacogenetics, metabolic genotyping, dose individualization, therapeutic drug monitoring, pharmacokinetics and pharmacodynamics, either alone or in combination, with original papers being selected based on the presence of relevant data. The findings of this review confirm the importance of considering individual patient characteristics to select IRI doses. Currently, the most straightforward approach for IRI dose individualization is UGT1A1 genotyping. However, this strategy is sub-optimal due to several other genetic and environmental contributions to the variable pharmacokinetics of IRI and its active metabolite. The use of dried blood spot sampling could allow the clinical application of complex sampling for the clinical use of limited sampling and population pharmacokinetic models for IRI doses individualization. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Spermidine rescues proximal tubular cells from oxidative stress and necrosis after ischemic acute kidney injury.

PubMed

Kim, Jinu

2017-10-01

Kidney ischemia and reperfusion injury (IRI) is associated with a high mortality rate, which is attributed to tubular oxidative stress and necrosis; however, an effective approach to limit IRI remains elusive. Spermidine, a naturally occurring polyamine, protects yeast cells against aging through the inhibition of oxidative stress and necrosis. In the present study, spermidine supplementation markedly attenuated increases in plasma creatinine concentration and tubular injury score after IRI. In addition, exogenous spermidine potently inhibited oxidative stress, especially lipid peroxidation after IRI in kidneys and exposure to hydrogen peroxide in kidney proximal tubular cells, suppressing plasma membrane disruption and necrosis. Consistent with spermidine supplementation, upregulation of ornithine decarboxylase (ODC) in human kidney proximal tubular cells significantly diminished lipid peroxidation and necrosis induced by hydrogen peroxide-induced injury. Conversely, ODC deficiency significantly enhanced lipid peroxidation and necrosis after exposure to hydrogen peroxide. Finally, small interfering RNA-mediated ODC inhibition induced functional and histological damage in kidneys as well as it increased lipid hydroperoxide levels after IRI. In conclusion, these data suggest that spermidine level determines kidney proximal tubular damage through oxidative stress and necrosis induced by IRI, and this finding provides a novel target for prevention of tubular damage induced by IRI.

IRI-2016: Description and Introduction

NASA Astrophysics Data System (ADS)

Bilitza, Dieter; Watanabe, Shigeto; Truhlik, Vladimir; Altadill, David

2016-07-01

The International Reference Ionosphere (IRI) is recognized as the official standard for the ionosphere (COSPAR, URSI, ISO) and is widely used for a multitude of different applications as evidenced by the many papers in science and engineering journals that acknowledge the use of IRI (e.g., about 11% of all Radio Science papers each year and citations in 21 different journals in 2015). The improvement process of the model is continuing as new data become fully available and new modeling techniques provide a more optimal representation of the observed variation patterns. We will introduce and present the latest version of the IRI model (IRI-2016) and discuss the impact of the various improvements and new additions. Most importantly, two new models will be introduced for the F2 peak height, hmF2, that were developed based on ionosonde measurements and COSMIC radio occultation data, respectively. In addition IRI-2016 includes an improved representation of the ionosphere during the very low solar activities that were reached during the last solar minimum in 2008/2009. A number of other improvements and corrections were implemented in the model and will be discussed in this presentation. We will also report about recent IRI workshops and their findings and plans for the future.

Pharmacology of Ischemia-Reperfusion. Translational Research Considerations.

PubMed

Prieto-Moure, Beatriz; Lloris-Carsí, José M; Barrios-Pitarque, Carlos; Toledo-Pereyra, Luis-H; Lajara-Romance, José María; Berda-Antolí, M; Lloris-Cejalvo, J M; Cejalvo-Lapeña, Dolores

2016-08-01

Ischemia-reperfusion (IRI) is a complex physiopathological mechanism involving a large number of metabolic processes that can eventually lead to cell apoptosis and ultimately tissue necrosis. Treatment approaches intended to reduce or palliate the effects of IRI are varied, and are aimed basically at: inhibiting cell apoptosis and the complement system in the inflammatory process deriving from IRI, modulating calcium levels, maintaining mitochondrial membrane integrity, reducing the oxidative effects of IRI and levels of inflammatory cytokines, or minimizing the action of macrophages, neutrophils, and other cell types. This study involved an extensive, up-to-date review of the bibliography on the currently most widely used active products in the treatment and prevention of IRI, and their mechanisms of action, in an aim to obtain an overview of current and potential future treatments for this pathological process. The importance of IRI is clearly reflected by the large number of studies published year after year, and by the variety of pathophysiological processes involved in this major vascular problem. A quick study of the evolution of IRI-related publications in PubMed shows that in a single month in 2014, 263 articles were published, compared to 806 articles in the entire 1990.

Update On Ink Jet Proofing

NASA Astrophysics Data System (ADS)

Santos, Richard P.

1989-04-01

IRIS Graphics, Inc., is a new start-up company chartered to develop, manufacture, and market direct digital filmless color imaging systems. IRIS is pleased to have been the recipient of the Graphic Art Technologies Foundation INTERTEC '87 Award for innovative excellence. IRIS is extremely proud to have been given this honor. IRIS was incorporated in April 1984 and received its initial funding of approximately 1 million by September 1984. The first 2044 Beta unit was installed in August 1985, and the first 2044 sales were made in December 1985 to R. R. Donnelley, the largest printer in the United States, and to G. S. Litho, the largest U.S. color separation house. In May 1986, IRIS received an additional 3 million in its second round of financing. A smaller version of the 2044, the 2024 was introduced at Lasers In Graphics in September 1986. IRIS achieved additional financing in July 1987 and completed the introduction of the new breakthrough Series 3000 again at Lasers In Graphics in September 1987 in Orlando, Florida. IRIS occupies 20,000 square feet at its new location in Bedford, Massachusetts, which located off of Route 128 in the high technology area near Boston.

Association between iris constitution and apolipoprotein e gene polymorphism in hypertensives.

PubMed

Um, Jae-Young; Hwang, Chung-Yeon; Hwang, Woo-Jun; Kang, Sung-Do; Do, Keum-Rok; Cho, Ju-Jang; Cho, Jae-Woon; Kim, Sung-Hoon; Shin, Tae-Yong; Kim, Yun-Kyung; Kim, Hyung-Min; Hong, Seung-Heon

2004-12-01

Iridology is a complementary and alternative medicine (CAM) that involves the diagnosis of medical conditions by noting irregularities of the pigmentation in the iris. Iris constitution has a strong familial aggregation and heredity is implicated. Apolipoprotein E (apoE) gene polymorphism is one of the most well-studied genetic markers for vascular diseases, including hypertension. In this study, we investigated the relationship between iris constitution and apoE polymorphism in hypertensives. We classified 87 hypertensives and 79 controls according to iris constitution and determined the apoE genotype of each individual. A significantly higher percentage of individuals with neurogenic constitutions was found in the hypertensive group when compared with the control group (chi(2) = 40.244, p < 0.001). In addition, a neurogenic constitution increased the relative risk for hypertension for subjects with an apo epsilon2 or an epsilon4 allele (chi(2) = 4.086, p = 0.049, odds ratio = 2.633, confidence interval = 1.004-6.905). Our results imply that a neurogenic iris constitution enhances the relative risk for hypertension in subjects with the apo epsilon2 or epsilon4 allele. Furthermore, we attempted to evaluate the efficacy of iris constitutional medicine and to find an association with hypertension.

IRIS Toxicological Review of Acrylonitrile (External Review Draft)

EPA Science Inventory

[UPDATE] New Schedule for IRIS Acrylonitrile Assessment

IRIS Toxicological Review of Trimethylbenzenes (Final Report)

EPA Science Inventory

EPA has finalized the Integrated Risk Information System (IRIS) Assessment of Trimethylbenzenes (TMBs). This assessment addresses the potential non-cancer and cancer human health effects from long-term exposure to TMBs. Now final, this assessment will be the first IRIS a...

IRIS Toxicological Review of Trimethylbenzenes (Interagency Science Discussion Draft)

EPA Science Inventory

In September 2016, EPA finalized the IRIS assessment of Trimethylbenzenes. The Toxicological Review was reviewed internally by EPA and by other federal agencies and White House Offices before public release in June 2016. Consistent with the May 2009 IRIS assessment development pr...

4-(2,4-Dichlorophenoxy)butyric acid (2,4-DB)

Integrated Risk Information System (IRIS)

Integrated Risk Information System ( IRIS ) Chemical Assessment Summary U.S . Environmental Protection Agency National Center for Environmental Assessment This IRIS Summary has been removed from the IRIS database and is available for historical reference purposes . ( July 2016 ) 4 - ( 2,4 - Dichloro

IRIS TOXICOLOGICAL REVIEW OF TETRACHLOROETHYLENE (PERCHLOROETHYLENE) (INTERAGENCY SCIENCE DISCUSSION DRAFT)

EPA Science Inventory

EPA is releasing the draft report, Toxicological Review of Tetrachloroethylene (Perchloroethylene), that was distributed to Federal agencies and White House Offices for comment during the Science Discussion step of the IRIS Assessment...

IRIS Toxicological Review of 2-Methylnaphthalene (2003, Final)

EPA Science Inventory

EPA announced the release of the final report, Toxicological Review of 2-Methylnaphthalene: in support of the Integrated Risk Information System (IRIS). The updated Summary for 2-Methylnaphthalene and accompanying toxicological review have also been added to the IRIS Datab...

IRIS Assessment Plan for Uranium (Scoping and Problem Formulation Materials)

EPA Science Inventory

In January 2018, EPA released the IRIS Assessment Plan for Uranium (Oral Reference Dose) (Scoping and Problem Formulation Materials). An IRIS Assessment Plan (IAP) communicates to the public the plan for assessing each individual chemical and includes summary informatio...

IRIS Toxicological Review of Vinyl Chloride (Final Report, 2000)

EPA Science Inventory

EPA is announcing the release of the final report, Toxicological Review of Vinyl Chloride: in support of the Integrated Risk Information System (IRIS). The updated Summary for Vinyl Chloride and accompanying Quickview have also been added to the IRIS Database.

IRIS thermal balance test within ESTEC LSS

NASA Technical Reports Server (NTRS)

Messidoro, Piero; Ballesio, Marino; Vessaz, J. P.

1988-01-01

The Italian Research Interim Stage (IRIS) thermal balance test was successfully performed in the ESTEC Large Space Simulator (LSS) to qualify the thermal design and to validate the thermal mathematical model. Characteristics of the test were the complexity of the set-up required to simulate the Shuttle cargo bay and allowing IRIS mechanism actioning and operation for the first time in the new LSS facility. Details of the test are presented, and test results for IRIS and the LSS facility are described.

Cysts of the Iris Pigment Epithelium. What Is New and Interesting? The 2016 Jose Rizal International Medal Lecture.

PubMed

Shields, Jerry A; Shields, Carol L

2017-01-01

Cysts of the iris pigment epithelium (IPE) can involve the pupillary margin, midzone, or peripheral location or can be free-floating in the aqueous or vitreous or lodged in the anterior chamber angle. Avariant of IPE cyst, known as iris flocculi, can be a marker for systemic thoracic aneurysm. Review of IPE cysts and description of new observations of the lesions. Review of IPE cysts. Lesions in 672 eyes were classified as of the pupillary margin (n = 49; 7%), midzone (n = 188; 28%), peripheral (n = 424; 63%), or dislodged/free-floating (n = 11; 2%). Cysts of the IPE occurred most often in young adults (21-40 years) (n = 229; 34%) manifesting with peripheral or midzonal cysts. The characteristic clinical features of pupillary margin cyst were teardrop configuration at the pupillary margin, midzonal cyst with fusiform brown appearance, peripheral cyst as iris stromal bulge, dislodged cyst as a brown lesion in the angle, and free-floating cyst with round mass moving by gravitational forces in the aqueous or vitreous. Ultrasound biomicroscopy and anterior segment optical coherence tomography demonstrated the lesions. Surgical intervention for drainage/resection was rarely necessary (<1%). Some (<1%) cysts were associated with iris nevus, iris melanoma, or ciliary body melanoma. Pupillary margin cysts (flocculi) can be found with dissecting thoracic aortic aneurysm, related to genetic mutation in smooth muscle of the iris and aorta. Cysts of the IPE most often affect the peripheral region (iridociliary) and rarely require intervention. These cysts can be associated with underlying iris or ciliary body nevus or melanoma. Patients with iris flocculi should be monitored for dissecting thoracic aneurysm. Copyright© 2017 Asia-Pacific Academy of Ophthalmology.

Intestinal ischemia/reperfusion injury triggers activation of innate toll-like receptor 4 and adaptive chemokine programs.

PubMed

Watson, M J; Ke, B; Shen, X-D; Gao, F; Busuttil, R W; Kupiec-Weglinski, J W; Farmer, D G

2008-12-01

Ischemia/reperfusion injury (IRI) is a major problem in intestinal transplantation. Toll-like receptor 4 (TLR4) has been implicated as a possible link between the innate and adaptive immune systems, however little data exists regarding TLR4 in intestinal IRI. The goal of this study is to evaluate the involvement of TLR4 in intestinal IRI and to assess the effect on T cell related chemokine programs. C57BL6 mice underwent 100 minutes of warm intestinal ischemia by SMA clamping. Control WT mice underwent laparotomy without vascular occlusion. Separate survival and analysis groups were performed, and intestinal tissue was harvested at 1 hour, 2 hours, 4 hours, and 24 hours post-reperfusion. Analysis included histology, CD3 immunostaining, myeloperoxidase activity, Western blot, and PCR. Survival was significantly worse in the IRI group vs control (50% vs. 100%). IRI caused severe histopathological injury including mucosal erosions and villous congestion and hemorrhage. Myeloperoxidase activity increased in a time-dependent manner after IRI (2.71 0.25 at 1 hour, 2.92 0.25 at 2 hours, 4 0.16 at 4 hours, 5.1 0.25 at 24 hours vs 0.47 0.11 controls, P < .05). Protein expression of TLR4 followed by NF-kappaB was increased after IRI. Additionally, mRNA production of IP-10, MIP-2, MCP-1, and RANTES was increased at all time-points, as was mRNA for ICAM-1 and E-selectin. This study is the first to demonstrate increased expression of TLR4 and NF-kappaB after warm intestinal IRI. This detrimental cascade may be initiated by TLR4 via NF-kappaB signaling pathways, implicating TLR4 as a potential therapeutic target for the prevention of intestinal IRI.