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Sample records for scene modeler msm

  1. Macro System Model (MSM) User Guide, Version 1.3

    Energy Technology Data Exchange (ETDEWEB)

    Ruth, M.; Diakov, V.; Sa, T.; Goldsby, M.

    2011-09-01

    This user guide describes the macro system model (MSM). The MSM has been designed to allow users to analyze the financial, environmental, transitional, geographical, and R&D issues associated with the transition to a hydrogen economy. Basic end users can use the MSM to answer cross-cutting questions that were previously difficult to answer in a consistent and timely manner due to various assumptions and methodologies among different models.

  2. A mathematical model of syphilis transmission in an MSM population.

    Science.gov (United States)

    Saad-Roy, C M; Shuai, Zhisheng; van den Driessche, P

    2016-07-01

    Syphilis is caused by the bacterium Treponema pallidum subspecies pallidum, and is a sexually transmitted disease with multiple stages. A model of transmission of syphilis in an MSM population (there has recently been a resurgence of syphilis in such populations) that includes infection stages and treatment is formulated as a system of ordinary differential equations. The control reproduction number is calculated, and it is proved that if this threshold parameter is below one, syphilis dies out; otherwise, if it is greater than one, it is shown that there exists a unique endemic equilibrium and that for certain special cases, this equilibrium is globally asymptotically stable. Using data from the literature on MSM populations, numerical methods are used to determine the variation and robustness of the control reproduction number with respect to the model parameters, and to determine adequate treatment rates for syphilis eradication. By assuming a closed population and no return to susceptibility, an epidemic model is obtained. Final outbreak sizes are numerically determined for various parameter values, and its variation and robustness to parameter value changes is also investigated. Results quantify the importance of early treatment for syphilis control. Copyright © 2016 Elsevier Inc. All rights reserved.

  3. Applying artificial vision models to human scene understanding.

    Science.gov (United States)

    Aminoff, Elissa M; Toneva, Mariya; Shrivastava, Abhinav; Chen, Xinlei; Misra, Ishan; Gupta, Abhinav; Tarr, Michael J

    2015-01-01

    How do we understand the complex patterns of neural responses that underlie scene understanding? Studies of the network of brain regions held to be scene-selective-the parahippocampal/lingual region (PPA), the retrosplenial complex (RSC), and the occipital place area (TOS)-have typically focused on single visual dimensions (e.g., size), rather than the high-dimensional feature space in which scenes are likely to be neurally represented. Here we leverage well-specified artificial vision systems to explicate a more complex understanding of how scenes are encoded in this functional network. We correlated similarity matrices within three different scene-spaces arising from: (1) BOLD activity in scene-selective brain regions; (2) behavioral measured judgments of visually-perceived scene similarity; and (3) several different computer vision models. These correlations revealed: (1) models that relied on mid- and high-level scene attributes showed the highest correlations with the patterns of neural activity within the scene-selective network; (2) NEIL and SUN-the models that best accounted for the patterns obtained from PPA and TOS-were different from the GIST model that best accounted for the pattern obtained from RSC; (3) The best performing models outperformed behaviorally-measured judgments of scene similarity in accounting for neural data. One computer vision method-NEIL ("Never-Ending-Image-Learner"), which incorporates visual features learned as statistical regularities across web-scale numbers of scenes-showed significant correlations with neural activity in all three scene-selective regions and was one of the two models best able to account for variance in the PPA and TOS. We suggest that these results are a promising first step in explicating more fine-grained models of neural scene understanding, including developing a clearer picture of the division of labor among the components of the functional scene-selective brain network.

  4. Applying artificial vision models to human scene understanding

    Directory of Open Access Journals (Sweden)

    Elissa Michele Aminoff

    2015-02-01

    Full Text Available How do we understand the complex patterns of neural responses that underlie scene understanding? Studies of the network of brain regions held to be scene-selective – the parahippocampal/lingual region (PPA, the retrosplenial complex (RSC, and the occipital place area (TOS – have typically focused on single visual dimensions (e.g., size, rather than the high-dimensional feature space in which scenes are likely to be neurally represented. Here we leverage well-specified artificial vision systems to explicate a more complex understanding of how scenes are encoded in this functional network. We correlated similarity matrices within three different scene-spaces arising from: 1 BOLD activity in scene-selective brain regions; 2 behavioral measured judgments of visually-perceived scene similarity; and 3 several different computer vision models. These correlations revealed: 1 models that relied on mid- and high-level scene attributes showed the highest correlations with the patterns of neural activity within the scene-selective network; 2 NEIL and SUN – the models that best accounted for the patterns obtained from PPA and TOS – were different from the GIST model that best accounted for the pattern obtained from RSC; 3 The best performing models outperformed behaviorally-measured judgments of scene similarity in accounting for neural data. One computer vision method – NEIL (Never-Ending-Image-Learner, which incorporates visual features learned as statistical regularities across web-scale numbers of scenes – showed significant correlations with neural activity in all three scene-selective regions and was one of the two models best able to account for variance in the PPA and TOS. We suggest that these results are a promising first step in explicating more fine-grained models of neural scene understanding, including developing a clearer picture of the division of labor among the components of the functional scene-selective brain network.

  5. Toward a full test of the ν MSM sterile neutrino dark matter model with Athena

    Science.gov (United States)

    Neronov, A.; Malyshev, D.

    2016-03-01

    We discuss the potential of Athena x-ray telescope, in particular of its x-ray integral field unit (X-IFU), for detection of the signal from the light-weight decaying dark matter with mass in the keV range. We show that high energy resolution and large collection area of X-IFU will provide an improvement of sensitivity which will be sufficient for the full test of the neutrino minimal extension of the standard modelMSM ). Search for the narrow spectral line produced by the decay of the dark matter sterile neutrino in the spectra of dwarf spheroidal galaxies with X-IFU will explore the whole allowed range masses and mixing angles of the ν MSM lightest sterile neutrino and in this way either to find the dark matter signal or rule out the ν MSM model.

  6. Psychometric assessment of HIV/STI sexual risk scale among MSM: A Rasch model approach

    Directory of Open Access Journals (Sweden)

    Liu Hui

    2011-10-01

    Full Text Available Abstract Background Little research has assessed the degree of severity and ordering of different types of sexual behaviors for HIV/STI infection in a measurement scale. The purpose of this study was to apply the Rasch model on psychometric assessment of an HIV/STI sexual risk scale among men who have sex with men (MSM. Methods A cross-sectional study using respondent driven sampling was conducted among 351 MSM in Shenzhen, China. The Rasch model was used to examine the psychometric properties of an HIV/STI sexual risk scale including nine types of sexual behaviors. Results The Rasch analysis of the nine items met the unidimensionality and local independence assumption. Although the person reliability was low at 0.35, the item reliability was high at 0.99. The fit statistics provided acceptable infit and outfit values. Item difficulty invariance analysis showed that the item estimates of the risk behavior items were invariant (within error. Conclusions The findings suggest that the Rasch model can be utilized for measuring the level of sexual risk for HIV/STI infection as a single latent construct and for establishing the relative degree of severity of each type of sexual behavior in HIV/STI transmission and acquisition among MSM. The measurement scale provides a useful measurement tool to inform, design and evaluate behavioral interventions for HIV/STI infection among MSM.

  7. Religion and Spirituality's Influences on HIV Syndemics Among MSM: A Systematic Review and Conceptual Model.

    Science.gov (United States)

    Lassiter, Jonathan M; Parsons, Jeffrey T

    2016-02-01

    This paper presents a systematic review of the quantitative HIV research that assessed the relationships between religion, spirituality, HIV syndemics, and individual HIV syndemics-related health conditions (e.g. depression, substance abuse, HIV risk) among men who have sex with men (MSM) in the United States. No quantitative studies were found that assessed the relationships between HIV syndemics, religion, and spirituality. Nine studies, with 13 statistical analyses, were found that examined the relationships between individual HIV syndemics-related health conditions, religion, and spirituality. Among the 13 analyses, religion and spirituality were found to have mixed relationships with HIV syndemics-related health conditions (6 nonsignificant associations; 5 negative associations; 2 positive associations). Given the overall lack of inclusion of religion and spirituality in HIV syndemics research, a conceptual model that hypothesizes the potential interactions of religion and spirituality with HIV syndemics-related health conditions is presented. The implications of the model for MSM's health are outlined.

  8. Picture models for 2-scene comics creating system

    Directory of Open Access Journals (Sweden)

    Miki UENO

    2015-03-01

    Full Text Available Recently, computer understanding pictures and stories becomes one of the most important research topics in computer science. However, there are few researches about human like understanding by computers because pictures have not certain format and contain more lyric aspect than that of natural laguage. For picture understanding, a comic is the suitable target because it is consisted by clear and simple plot of stories and separated scenes.In this paper, we propose 2 different types of picture models for 2-scene comics creating system. We also show the method of the application of 2-scene comics creating system by means of proposed picture model.

  9. Digital forensics: an analytical crime scene procedure model (ACSPM).

    Science.gov (United States)

    Bulbul, Halil Ibrahim; Yavuzcan, H Guclu; Ozel, Mesut

    2013-12-10

    In order to ensure that digital evidence is collected, preserved, examined, or transferred in a manner safeguarding the accuracy and reliability of the evidence, law enforcement and digital forensic units must establish and maintain an effective quality assurance system. The very first part of this system is standard operating procedures (SOP's) and/or models, conforming chain of custody requirements, those rely on digital forensics "process-phase-procedure-task-subtask" sequence. An acceptable and thorough Digital Forensics (DF) process depends on the sequential DF phases, and each phase depends on sequential DF procedures, respectively each procedure depends on tasks and subtasks. There are numerous amounts of DF Process Models that define DF phases in the literature, but no DF model that defines the phase-based sequential procedures for crime scene identified. An analytical crime scene procedure model (ACSPM) that we suggest in this paper is supposed to fill in this gap. The proposed analytical procedure model for digital investigations at a crime scene is developed and defined for crime scene practitioners; with main focus on crime scene digital forensic procedures, other than that of whole digital investigation process and phases that ends up in a court. When reviewing the relevant literature and interrogating with the law enforcement agencies, only device based charts specific to a particular device and/or more general perspective approaches to digital evidence management models from crime scene to courts are found. After analyzing the needs of law enforcement organizations and realizing the absence of crime scene digital investigation procedure model for crime scene activities we decided to inspect the relevant literature in an analytical way. The outcome of this inspection is our suggested model explained here, which is supposed to provide guidance for thorough and secure implementation of digital forensic procedures at a crime scene. In digital forensic

  10. Early HAART Initiation May Not Reduce Actual Reproduction Number and Prevalence of MSM Infection: Perspectives from Coupled within- and between-Host Modelling Studies of Chinese MSM Populations: e0150513

    National Research Council Canada - National Science Library

    Xiaodan Sun; Yanni Xiao; Sanyi Tang; Zhihang Peng; Jianhong Wu; Ning Wang

    2016-01-01

    ...) on disease transmission at the population level. We proposed an individual based model by coupling within-host dynamics and between-host dynamics and conduct stochastic simulation in the group of men who have sex with men (MSM...

  11. Early HAART Initiation May Not Reduce Actual Reproduction Number and Prevalence of MSM Infection: Perspectives from Coupled within- and between-Host Modelling Studies of Chinese MSM Populations.

    Directory of Open Access Journals (Sweden)

    Xiaodan Sun

    Full Text Available Having a thorough understanding of the infectivity of HIV, time of initiating treatment and emergence of drug resistant virus variants is crucial in mitigating HIV infection. There are many challenges to evaluating the long-term effect of the Highly Active Antiretroviral Therapy (HAART on disease transmission at the population level. We proposed an individual based model by coupling within-host dynamics and between-host dynamics and conduct stochastic simulation in the group of men who have sex with men (MSM. The mean actual reproduction number is estimated to be 3.6320 (95% confidence interval: [3.46, 3.80] for MSM group without treatment. Stochastic simulations show that given relatively high (low level of drug efficacy after emergence of drug resistant variants, early initiation of treatment leads to a less (greater actual reproduction number, lower (higher prevalence and less (more incidences, compared to late initiation of treatment. This implies early initiation of HAART may not always lower the actual reproduction number and prevalence of infection, depending on the level of treatment efficacy after emergence of drug resistant virus variants, frequency of high-risk behaviors and etc. This finding strongly suggests early initiation of HAART should be implemented with great care especially in the settings where the effective drugs are limited. Coupling within-host dynamics with between-host dynamics can provide critical information about impact of HAART on disease transmission and thus help to assist treatment strategy design and HIV/AIDS prevention and control.

  12. Modelling Technology for Building Fire Scene with Virtual Geographic Environment

    Science.gov (United States)

    Song, Y.; Zhao, L.; Wei, M.; Zhang, H.; Liu, W.

    2017-09-01

    Building fire is a risky activity that can lead to disaster and massive destruction. The management and disposal of building fire has always attracted much interest from researchers. Integrated Virtual Geographic Environment (VGE) is a good choice for building fire safety management and emergency decisions, in which a more real and rich fire process can be computed and obtained dynamically, and the results of fire simulations and analyses can be much more accurate as well. To modelling building fire scene with VGE, the application requirements and modelling objective of building fire scene were analysed in this paper. Then, the four core elements of modelling building fire scene (the building space environment, the fire event, the indoor Fire Extinguishing System (FES) and the indoor crowd) were implemented, and the relationship between the elements was discussed also. Finally, with the theory and framework of VGE, the technology of building fire scene system with VGE was designed within the data environment, the model environment, the expression environment, and the collaborative environment as well. The functions and key techniques in each environment are also analysed, which may provide a reference for further development and other research on VGE.

  13. Dynamic scene stitching driven by visual cognition model.

    Science.gov (United States)

    Zou, Li-hui; Zhang, Dezheng; Wulamu, Aziguli

    2014-01-01

    Dynamic scene stitching still has a great challenge in maintaining the global key information without missing or deforming if multiple motion interferences exist in the image acquisition system. Object clips, motion blurs, or other synthetic defects easily occur in the final stitching image. In our research work, we proceed from human visual cognitive mechanism and construct a hybrid-saliency-based cognitive model to automatically guide the video volume stitching. The model consists of three elements of different visual stimuli, that is, intensity, edge contour, and scene depth saliencies. Combined with the manifold-based mosaicing framework, dynamic scene stitching is formulated as a cut path optimization problem in a constructed space-time graph. The cutting energy function for column width selections is defined according to the proposed visual cognition model. The optimum cut path can minimize the cognitive saliency difference throughout the whole video volume. The experimental results show that it can effectively avoid synthetic defects caused by different motion interferences and summarize the key contents of the scene without loss. The proposed method gives full play to the role of human visual cognitive mechanism for the stitching. It is of high practical value to environmental surveillance and other applications.

  14. Dynamic Scene Stitching Driven by Visual Cognition Model

    Directory of Open Access Journals (Sweden)

    Li-hui Zou

    2014-01-01

    Full Text Available Dynamic scene stitching still has a great challenge in maintaining the global key information without missing or deforming if multiple motion interferences exist in the image acquisition system. Object clips, motion blurs, or other synthetic defects easily occur in the final stitching image. In our research work, we proceed from human visual cognitive mechanism and construct a hybrid-saliency-based cognitive model to automatically guide the video volume stitching. The model consists of three elements of different visual stimuli, that is, intensity, edge contour, and scene depth saliencies. Combined with the manifold-based mosaicing framework, dynamic scene stitching is formulated as a cut path optimization problem in a constructed space-time graph. The cutting energy function for column width selections is defined according to the proposed visual cognition model. The optimum cut path can minimize the cognitive saliency difference throughout the whole video volume. The experimental results show that it can effectively avoid synthetic defects caused by different motion interferences and summarize the key contents of the scene without loss. The proposed method gives full play to the role of human visual cognitive mechanism for the stitching. It is of high practical value to environmental surveillance and other applications.

  15. Toward Holistic Scene Understanding: Feedback Enabled Cascaded Classification Models.

    Science.gov (United States)

    Li, Congcong; Kowdle, Adarsh; Saxena, Ashutosh; Chen, Tsuhan

    2012-07-01

    Scene understanding includes many related subtasks, such as scene categorization, depth estimation, object detection, etc. Each of these subtasks is often notoriously hard, and state-of-the-art classifiers already exist for many of them. These classifiers operate on the same raw image and provide correlated outputs. It is desirable to have an algorithm that can capture such correlation without requiring any changes to the inner workings of any classifier. We propose Feedback Enabled Cascaded Classification Models (FE-CCM), that jointly optimizes all the subtasks while requiring only a "black box" interface to the original classifier for each subtask. We use a two-layer cascade of classifiers, which are repeated instantiations of the original ones, with the output of the first layer fed into the second layer as input. Our training method involves a feedback step that allows later classifiers to provide earlier classifiers information about which error modes to focus on. We show that our method significantly improves performance in all the subtasks in the domain of scene understanding, where we consider depth estimation, scene categorization, event categorization, object detection, geometric labeling, and saliency detection. Our method also improves performance in two robotic applications: an object-grasping robot and an object-finding robot.

  16. A corticothalamic circuit model for sound identification in complex scenes.

    Directory of Open Access Journals (Sweden)

    Gonzalo H Otazu

    Full Text Available The identification of the sound sources present in the environment is essential for the survival of many animals. However, these sounds are not presented in isolation, as natural scenes consist of a superposition of sounds originating from multiple sources. The identification of a source under these circumstances is a complex computational problem that is readily solved by most animals. We present a model of the thalamocortical circuit that performs level-invariant recognition of auditory objects in complex auditory scenes. The circuit identifies the objects present from a large dictionary of possible elements and operates reliably for real sound signals with multiple concurrently active sources. The key model assumption is that the activities of some cortical neurons encode the difference between the observed signal and an internal estimate. Reanalysis of awake auditory cortex recordings revealed neurons with patterns of activity corresponding to such an error signal.

  17. A combined feature latent semantic model for scene classification

    Science.gov (United States)

    Jiang, Yue; Wang, Runsheng

    2009-10-01

    Due to vast growth of image databases, scene image classification methods have become increasingly important in computer vision areas. We propose a new scene image classification framework based on combined feature and a latent semantic model which is based on the Latent Dirichlet Allocation (LDA) in the statistical text literature. Here the model is applied to visual words representation for images. We use Gibbs sampling for parameter estimation and use several different numbers of topics at the same time to obtain the latent topic representation of images. We densely extract multi-scale patches from images and get the combined feature on these patches. Our method is unsupervised. It can also well represent semantic characteristic of images. We demonstrate the effectiveness of our approach by comparing it to those used in previous work in this area. Experiments were conducted on three often used image databases, and our method got better results than the others.

  18. Human supervisory approach to modeling industrial scenes using geometric primitives

    Energy Technology Data Exchange (ETDEWEB)

    Luck, J.P.; Little, C.Q.; Roberts, R.S.

    1997-11-19

    A three-dimensional world model is crucial for many robotic tasks. Modeling techniques tend to be either fully manual or autonomous. Manual methods are extremely time consuming but also highly accurate and flexible. Autonomous techniques are fast but inflexible and, with real-world data, often inaccurate. The method presented in this paper combines the two, yielding a highly efficient, flexible, and accurate mapping tool. The segmentation and modeling algorithms that compose the method are specifically designed for industrial environments, and are described in detail. A mapping system based on these algorithms has been designed. It enables a human supervisor to quickly construct a fully defined world model from unfiltered and unsegmented real-world range imagery. Examples of how industrial scenes are modeled with the mapping system are provided.

  19. Adapting Andersen's Behavioral Model of Health Service Use to Examine Risk Factors for Hypertension Among U.S. MSM.

    Science.gov (United States)

    Hirshfield, Sabina; Downing, Martin J; Horvath, Keith J; Swartz, James A; Chiasson, Mary Ann

    2016-04-19

    Hypertension affects nearly a third of U.S. adult males and is a leading risk factor for cardiovascular disease, but there is a paucity of hypertension research among men who have sex with men (MSM). Andersen's model of health service use was adapted to examine factors associated with hypertension among MSM. In 2008, 7,454 U.S. MSM completed an online survey. Overall, 16.5% of the sample reported a lifetime diagnosis of hypertension. In hierarchical logistic regression, Black MSM had increased odds of reporting hypertension (adjusted odds ratio [AOR] = 1.79, 95% confidence interval [CI] [1.24, 2.60]) compared with White MSM, as did men aged 30 years and older (age 30-39: AOR = 2.46, 95% CI [1.84, 3.29]; age 40-49: AOR = 3.76, 95% CI [2.85, 4.97]; age 50+: AOR = 6.40, 95% CI [4.78, 8.58]; Reference: 18-29 years). Health conditions associated with hypertension included diabetes (AOR = 3.62, 95% CI [2.81, 4.68]), heart disease (AOR = 5.19, 95% CI [3.99, 6.75]), depression (AOR = 1.38, 95% CI [1.17, 1.63]), anxiety (AOR = 1.30, 95% CI [1.09, 1.57]), and being overweight (AOR = 2.23, 95% CI [1.91, 2.59]). Having a primary care provider (AOR = 2.19, 95% CI [1.64, 2.93]) and residing in South Atlantic (AOR = 1.39, 95% CI [1.12, 1.74]) or South Central (AOR = 1.59, 95% CI [1.27, 2.00]) regions was also associated with reporting hypertension. Study findings are consistent with those in the literature for the general population. To address health care inequities, the Internet could serve as a potential access point for health screening and referral for care. © The Author(s) 2016.

  20. CRISP: A Computational Model of Fixation Durations in Scene Viewing

    Science.gov (United States)

    Nuthmann, Antje; Smith, Tim J.; Engbert, Ralf; Henderson, John M.

    2010-01-01

    Eye-movement control during scene viewing can be represented as a series of individual decisions about where and when to move the eyes. While substantial behavioral and computational research has been devoted to investigating the placement of fixations in scenes, relatively little is known about the mechanisms that control fixation durations.…

  1. STAC: a comprehensive sensor fusion model for scene characterization

    Science.gov (United States)

    Kira, Zsolt; Wagner, Alan R.; Kennedy, Chris; Zutty, Jason; Tuell, Grady

    2015-05-01

    We are interested in data fusion strategies for Intelligence, Surveillance, and Reconnaissance (ISR) missions. Advances in theory, algorithms, and computational power have made it possible to extract rich semantic information from a wide variety of sensors, but these advances have raised new challenges in fusing the data. For example, in developing fusion algorithms for moving target identification (MTI) applications, what is the best way to combine image data having different temporal frequencies, and how should we introduce contextual information acquired from monitoring cell phones or from human intelligence? In addressing these questions we have found that existing data fusion models do not readily facilitate comparison of fusion algorithms performing such complex information extraction, so we developed a new model that does. Here, we present the Spatial, Temporal, Algorithm, and Cognition (STAC) model. STAC allows for describing the progression of multi-sensor raw data through increasing levels of abstraction, and provides a way to easily compare fusion strategies. It provides for unambiguous description of how multi-sensor data are combined, the computational algorithms being used, and how scene understanding is ultimately achieved. In this paper, we describe and illustrate the STAC model, and compare it to other existing models.

  2. METRIC EVALUATION PIPELINE FOR 3D MODELING OF URBAN SCENES

    Directory of Open Access Journals (Sweden)

    M. Bosch

    2017-05-01

    Full Text Available Publicly available benchmark data and metric evaluation approaches have been instrumental in enabling research to advance state of the art methods for remote sensing applications in urban 3D modeling. Most publicly available benchmark datasets have consisted of high resolution airborne imagery and lidar suitable for 3D modeling on a relatively modest scale. To enable research in larger scale 3D mapping, we have recently released a public benchmark dataset with multi-view commercial satellite imagery and metrics to compare 3D point clouds with lidar ground truth. We now define a more complete metric evaluation pipeline developed as publicly available open source software to assess semantically labeled 3D models of complex urban scenes derived from multi-view commercial satellite imagery. Evaluation metrics in our pipeline include horizontal and vertical accuracy and completeness, volumetric completeness and correctness, perceptual quality, and model simplicity. Sources of ground truth include airborne lidar and overhead imagery, and we demonstrate a semi-automated process for producing accurate ground truth shape files to characterize building footprints. We validate our current metric evaluation pipeline using 3D models produced using open source multi-view stereo methods. Data and software is made publicly available to enable further research and planned benchmarking activities.

  3. Metric Evaluation Pipeline for 3d Modeling of Urban Scenes

    Science.gov (United States)

    Bosch, M.; Leichtman, A.; Chilcott, D.; Goldberg, H.; Brown, M.

    2017-05-01

    Publicly available benchmark data and metric evaluation approaches have been instrumental in enabling research to advance state of the art methods for remote sensing applications in urban 3D modeling. Most publicly available benchmark datasets have consisted of high resolution airborne imagery and lidar suitable for 3D modeling on a relatively modest scale. To enable research in larger scale 3D mapping, we have recently released a public benchmark dataset with multi-view commercial satellite imagery and metrics to compare 3D point clouds with lidar ground truth. We now define a more complete metric evaluation pipeline developed as publicly available open source software to assess semantically labeled 3D models of complex urban scenes derived from multi-view commercial satellite imagery. Evaluation metrics in our pipeline include horizontal and vertical accuracy and completeness, volumetric completeness and correctness, perceptual quality, and model simplicity. Sources of ground truth include airborne lidar and overhead imagery, and we demonstrate a semi-automated process for producing accurate ground truth shape files to characterize building footprints. We validate our current metric evaluation pipeline using 3D models produced using open source multi-view stereo methods. Data and software is made publicly available to enable further research and planned benchmarking activities.

  4. Using the Information-Motivation-Behavioral Skills Model to Guide the Development of an HIV Prevention Smartphone Application for High-Risk MSM.

    Science.gov (United States)

    Aliabadi, Negar; Carballo-Dieguez, Alex; Bakken, Suzanne; Rojas, Marlene; Brown, William; Carry, Monique; Mosley, Jocelyn Patterson; Gelaude, Deborah; Schnall, Rebecca

    2015-12-01

    HIV remains a significant public health problem among men who have sex with men (MSM). MSM comprise 2% of the U.S. population, but constitute 56% of persons living with HIV. Mobile health technology is a promising tool for HIV prevention. The purpose of this study was to identify the desired content, features and functions of a mobile application (app) for HIV prevention in high-risk MSM. We conducted five focus group sessions with 33 MSM. Focus group recordings were transcribed and coded using themes informed by the information-motivation-behavioral (IMB) skills model. Participants identified information needs related to HIV prevention: HIV testing and prophylaxis distribution centers, support groups/peers, and HIV/STI disease/treatment information. Areas of motivation to target for the app included: attitudes and intentions. Participants identified behavioral skills to address with an app: using condoms correctly, negotiating safer sex, recognizing signs of HIV/STI. Findings from this work provide insight into the desired content of a mobile app for HIV prevention in high-risk MSM.

  5. Virtual simulation-based scene modeling of helicopter earthquake search and rescue

    Science.gov (United States)

    Sun, Xue; Liu, Hu; Yang, Chenguang; Wang, Ning

    2017-05-01

    The characteristics of helicopter earthquake search and rescue (HESAR) oriented virtual simulation scene are summarized to guide the modeling of virtual simulation scene. Then a method of scene modeling which can satisfy the simulation requirements and simplify the modeling is proposed. The seismic influence field is first determined by inversion to get the distribution of buildings with different damage grades. And then, the division of different levels of detail (LOD) regions where the intricacy requirements of modeling are different is obtained to simplify the modeling. Besides, Unity3D is used for the three-dimensional terrain construction and scene rendering. Finally, a sample case was shown to verify the effectiveness of the proposed method.

  6. The SEM Risk Behavior (SRB) Model: A New Conceptual Model of how Pornography Influences the Sexual Intentions and HIV Risk Behavior of MSM.

    Science.gov (United States)

    Wilkerson, J Michael; Iantaffi, Alex; Smolenski, Derek J; Brady, Sonya S; Horvath, Keith J; Grey, Jeremy A; Rosser, B R Simon

    2012-01-01

    While the effects of sexually explicit media (SEM) on heterosexuals' sexual intentions and behaviors have been studied, little is known about the consumption and possible influence of SEM among men who have sex with men (MSM). Importantly, conceptual models of how Internet-based SEM influences behavior are lacking. Seventy-nine MSM participated in online focus groups about their SEM viewing preferences and sexual behavior. Twenty-three participants reported recent exposure to a new behavior via SEM. Whether participants modified their sexual intentions and/or engaged in the new behavior depended on three factors: arousal when imagining the behavior, pleasure when attempting the behavior, and trust between sex partners. Based on MSM's experience, we advance a model of how viewing a new sexual behavior in SEM influences sexual intentions and behaviors. The model includes five paths. Three paths result in the maintenance of sexual intentions and behaviors. One path results in a modification of sexual intentions while maintaining previous sexual behaviors, and one path results in a modification of both sexual intentions and behaviors. With this model, researchers have a framework to test associations between SEM consumption and sexual intentions and behavior, and public health programs have a framework to conceptualize SEM-based HIV/STI prevention programs.

  7. Hierarchical Model for the Similarity Measurement of a Complex Holed-Region Entity Scene

    Directory of Open Access Journals (Sweden)

    Zhanlong Chen

    2017-11-01

    Full Text Available Complex multi-holed-region entity scenes (i.e., sets of random region with holes are common in spatial database systems, spatial query languages, and the Geographic Information System (GIS. A multi-holed-region (region with an arbitrary number of holes is an abstraction of the real world that primarily represents geographic objects that have more than one interior boundary, such as areas that contain several lakes or lakes that contain islands. When the similarity of the two complex holed-region entity scenes is measured, the number of regions in the scenes and the number of holes in the regions are usually different between the two scenes, which complicates the matching relationships of holed-regions and holes. The aim of this research is to develop several holed-region similarity metrics and propose a hierarchical model to measure comprehensively the similarity between two complex holed-region entity scenes. The procedure first divides a complex entity scene into three layers: a complex scene, a micro-spatial-scene, and a simple entity (hole. The relationships between the adjacent layers are considered to be sets of relationships, and each level of similarity measurements is nested with the adjacent one. Next, entity matching is performed from top to bottom, while the similarity results are calculated from local to global. In addition, we utilize position graphs to describe the distribution of the holed-regions and subsequently describe the directions between the holes using a feature matrix. A case study that uses the Great Lakes in North America in 1986 and 2015 as experimental data illustrates the entire similarity measurement process between two complex holed-region entity scenes. The experimental results show that the hierarchical model accounts for the relationships of the different layers in the entire complex holed-region entity scene. The model can effectively calculate the similarity of complex holed-region entity scenes, even if the

  8. Religion and Spirituality’s Influences on HIV Syndemics Among MSM: A Systematic Review and Conceptual Model

    Science.gov (United States)

    Parsons, Jeffrey T.

    2015-01-01

    This paper presents a systematic review of the quantitative HIV research that assessed the relationships between religion, spirituality, HIV syndemics, and individual HIV syndemics-related health conditions (e.g. depression, substance abuse, HIV risk) among men who have sex with men (MSM) in the United States. No quantitative studies were found that assessed the relationships between HIV syndemics, religion, and spirituality. Nine studies, with 13 statistical analyses, were found that examined the relationships between individual HIV syndemics-related health conditions, religion, and spirituality. Among the 13 analyses, religion and spirituality were found to have mixed relationships with HIV syndemics-related health conditions (6 nonsignificant associations; 5 negative associations; 2 positive associations). Given the overall lack of inclusion of religion and spirituality in HIV syndemics research, a conceptual model that hypothesizes the potential interactions of religion and spirituality with HIV syndemics-related health conditions is presented. The implications of the model for MSM’s health are outlined. PMID:26319130

  9. Real-time mid-wavelength infrared scene rendering with a feasible BRDF model

    Science.gov (United States)

    Wu, Xin; Zhang, Jianqi; Chen, Yang; Huang, Xi

    2015-01-01

    Practically modeling and rendering the surface-leaving radiance of large-scale scenes in mid-wavelength infrared (MWIR) is an important feature of Battlefield Environment Simulation (BES). Since radiation transfer in realistic scenes is complex, it is difficult to develop real-time simulations directly from first principle. Nevertheless, it is crucial to minimize distortions in the rendering of virtual scenes. This paper proposes a feasible bidirectional reflectance distribution function (BRDF) model to deal with a large-scale scene in the MWIR band. Our BRDF model is spectrally dependent and evolved from previous BRDFs, and meets both Helmholtz reciprocity and energy conservation. We employ our BRDF model to calculate the direct solar and sky contributions. Both of them are added to the surface thermal emission in order to give the surface-leaving radiance. Atmospheric path radiance and transmission are pre-calculated to speed up the programming for rendering large scale scenes. Quantitative and qualitative comparisons with MWIR field data are made to assess the render results of our proposed method.

  10. Desensitization and Modeling Treatments of Spider Fear Using Two Types of Scenes

    Science.gov (United States)

    Denney, Douglas R.; Sullivan, Bernard J.

    1976-01-01

    Three types of therapy were combined with two types of scenes. Spider-phobic subjects were assigned to one of the six treatment conditions or to an untreated control group. In general, (a) Desensitization and modeling therapies were equally effective; (b) modeling alone was more effective than mere exposure to the phobic object. (Author)

  11. Walk This Way: Improving Pedestrian Agent-Based Models through Scene Activity Analysis

    Directory of Open Access Journals (Sweden)

    Andrew Crooks

    2015-09-01

    Full Text Available Pedestrian movement is woven into the fabric of urban regions. With more people living in cities than ever before, there is an increased need to understand and model how pedestrians utilize and move through space for a variety of applications, ranging from urban planning and architecture to security. Pedestrian modeling has been traditionally faced with the challenge of collecting data to calibrate and validate such models of pedestrian movement. With the increased availability of mobility datasets from video surveillance and enhanced geolocation capabilities in consumer mobile devices we are now presented with the opportunity to change the way we build pedestrian models. Within this paper we explore the potential that such information offers for the improvement of agent-based pedestrian models. We introduce a Scene- and Activity-Aware Agent-Based Model (SA2-ABM, a method for harvesting scene activity information in the form of spatiotemporal trajectories, and incorporate this information into our models. In order to assess and evaluate the improvement offered by such information, we carry out a range of experiments using real-world datasets. We demonstrate that the use of real scene information allows us to better inform our model and enhance its predictive capabilities.

  12. Fourier power, subjective distance and object categories all provide plausible models of BOLD responses in scene-selective visual areas

    Directory of Open Access Journals (Sweden)

    Mark Daniel Lescroart

    2015-11-01

    Full Text Available Perception of natural visual scenes activates several functional areas in the human brain, including the Parahippocampal Place Area (PPA, Retrosplenial Complex (RSC, and the Occipital Place Area (OPA. It is currently unclear what specific scene-related features are represented in these areas. Previous studies have suggested that PPA, RSC, and/or OPA might represent at least three qualitatively different classes of features: (1 2D features related to Fourier power; (2 3D spatial features such as the distance to objects in a scene; or (3 abstract features such as the categories of objects in a scene. To determine which of these hypotheses best describes the visual representation in scene-selective areas, we applied voxel-wise modeling (VM to BOLD fMRI responses elicited by a set of 1,386 images of natural scenes. VM provides an efficient method for testing competing hypotheses by comparing predictions of brain activity based on encoding models that instantiate each hypothesis. Here we evaluated three different encoding models that instantiate each of the three hypotheses listed above. We used linear regression to fit each encoding model to the fMRI data recorded from each voxel, and we evaluated each fit model by estimating the amount of variance it predicted in a withheld portion of the data set. We found that voxel-wise models based on Fourier power or the subjective distance to objects in each scene predicted much of the variance predicted by a model based on object categories. Furthermore, the response variance explained by these three models is largely shared, and the individual models explain little unique variance in responses. Based on an evaluation of previous studies and the data we present here, we conclude that there is currently no good basis to favor any one of the three alternative hypotheses about visual representation in scene-selective areas. We offer suggestions for further studies that may help resolve this issue.

  13. Fourier power, subjective distance, and object categories all provide plausible models of BOLD responses in scene-selective visual areas

    Science.gov (United States)

    Lescroart, Mark D.; Stansbury, Dustin E.; Gallant, Jack L.

    2015-01-01

    Perception of natural visual scenes activates several functional areas in the human brain, including the Parahippocampal Place Area (PPA), Retrosplenial Complex (RSC), and the Occipital Place Area (OPA). It is currently unclear what specific scene-related features are represented in these areas. Previous studies have suggested that PPA, RSC, and/or OPA might represent at least three qualitatively different classes of features: (1) 2D features related to Fourier power; (2) 3D spatial features such as the distance to objects in a scene; or (3) abstract features such as the categories of objects in a scene. To determine which of these hypotheses best describes the visual representation in scene-selective areas, we applied voxel-wise modeling (VM) to BOLD fMRI responses elicited by a set of 1386 images of natural scenes. VM provides an efficient method for testing competing hypotheses by comparing predictions of brain activity based on encoding models that instantiate each hypothesis. Here we evaluated three different encoding models that instantiate each of the three hypotheses listed above. We used linear regression to fit each encoding model to the fMRI data recorded from each voxel, and we evaluated each fit model by estimating the amount of variance it predicted in a withheld portion of the data set. We found that voxel-wise models based on Fourier power or the subjective distance to objects in each scene predicted much of the variance predicted by a model based on object categories. Furthermore, the response variance explained by these three models is largely shared, and the individual models explain little unique variance in responses. Based on an evaluation of previous studies and the data we present here, we conclude that there is currently no good basis to favor any one of the three alternative hypotheses about visual representation in scene-selective areas. We offer suggestions for further studies that may help resolve this issue. PMID:26594164

  14. DETECTION OF TEXT OBJECTS IN IMAGES OF REAL SCENES BASED ON CONVOLUTIONAL NEURAL NETWORK MODEL

    Directory of Open Access Journals (Sweden)

    N. N. Kuzmitsky

    2015-01-01

    Full Text Available A model of text image detector based on a convolutional neural network architecture is presented, capable of synthesizing high-level features of images in the «black box» mode. An implementation of the detector application, based on algorithms of multi-scale scanning and local responses interpretation is described, allowing to find out text samples on images of real scenes. Advantages in comparison with analogs are shown and efficiency evaluation on an example of a known database is conducted.

  15. Modelling a crime scene in 3D and adding thermal information

    NARCIS (Netherlands)

    Iersel, M. van; Veerman, H.E.T.; Mark, W. van der

    2009-01-01

    Once a crime has been perpetrated, forensic traces will only be persevered in the crime scene for a limited time frame. It is therefore necessary to record a crime scene meticulously. Usually, photographs and/or videos are taken at the scene to document it, so that later on one will know the exact

  16. Depth-color fusion strategy for 3-D scene modeling with Kinect.

    Science.gov (United States)

    Camplani, Massimo; Mantecon, Tomas; Salgado, Luis

    2013-12-01

    Low-cost depth cameras, such as Microsoft Kinect, have completely changed the world of human-computer interaction through controller-free gaming applications. Depth data provided by the Kinect sensor presents several noise-related problems that have to be tackled to improve the accuracy of the depth data, thus obtaining more reliable game control platforms and broadening its applicability. In this paper, we present a depth-color fusion strategy for 3-D modeling of indoor scenes with Kinect. Accurate depth and color models of the background elements are iteratively built, and used to detect moving objects in the scene. Kinect depth data is processed with an innovative adaptive joint-bilateral filter that efficiently combines depth and color by analyzing an edge-uncertainty map and the detected foreground regions. Results show that the proposed approach efficiently tackles main Kinect data problems: distance-dependent depth maps, spatial noise, and temporal random fluctuations are dramatically reduced; objects depth boundaries are refined, and nonmeasured depth pixels are interpolated. Moreover, a robust depth and color background model and accurate moving objects silhouette are generated.

  17. Data for MSM example application for MSM manuscript

    Data.gov (United States)

    U.S. Environmental Protection Agency — Input data used by the MSM and HSPF for QMRA application to the Manitowoc Basin. This dataset is associated with the following publication: Whelan, G., K. Kim, R....

  18. SCENE CLASSFICATION BASED ON THE SEMANTIC-FEATURE FUSION FULLY SPARSE TOPIC MODEL FOR HIGH SPATIAL RESOLUTION REMOTE SENSING IMAGERY

    Directory of Open Access Journals (Sweden)

    Q. Zhu

    2016-06-01

    Full Text Available Topic modeling has been an increasingly mature method to bridge the semantic gap between the low-level features and high-level semantic information. However, with more and more high spatial resolution (HSR images to deal with, conventional probabilistic topic model (PTM usually presents the images with a dense semantic representation. This consumes more time and requires more storage space. In addition, due to the complex spectral and spatial information, a combination of multiple complementary features is proved to be an effective strategy to improve the performance for HSR image scene classification. But it should be noticed that how the distinct features are fused to fully describe the challenging HSR images, which is a critical factor for scene classification. In this paper, a semantic-feature fusion fully sparse topic model (SFF-FSTM is proposed for HSR imagery scene classification. In SFF-FSTM, three heterogeneous features – the mean and standard deviation based spectral feature, wavelet based texture feature, and dense scale-invariant feature transform (SIFT based structural feature are effectively fused at the latent semantic level. The combination of multiple semantic-feature fusion strategy and sparse based FSTM is able to provide adequate feature representations, and can achieve comparable performance with limited training samples. Experimental results on the UC Merced dataset and Google dataset of SIRI-WHU demonstrate that the proposed method can improve the performance of scene classification compared with other scene classification methods for HSR imagery.

  19. Scene Classfication Based on the Semantic-Feature Fusion Fully Sparse Topic Model for High Spatial Resolution Remote Sensing Imagery

    Science.gov (United States)

    Zhu, Qiqi; Zhong, Yanfei; Zhang, Liangpei

    2016-06-01

    Topic modeling has been an increasingly mature method to bridge the semantic gap between the low-level features and high-level semantic information. However, with more and more high spatial resolution (HSR) images to deal with, conventional probabilistic topic model (PTM) usually presents the images with a dense semantic representation. This consumes more time and requires more storage space. In addition, due to the complex spectral and spatial information, a combination of multiple complementary features is proved to be an effective strategy to improve the performance for HSR image scene classification. But it should be noticed that how the distinct features are fused to fully describe the challenging HSR images, which is a critical factor for scene classification. In this paper, a semantic-feature fusion fully sparse topic model (SFF-FSTM) is proposed for HSR imagery scene classification. In SFF-FSTM, three heterogeneous features - the mean and standard deviation based spectral feature, wavelet based texture feature, and dense scale-invariant feature transform (SIFT) based structural feature are effectively fused at the latent semantic level. The combination of multiple semantic-feature fusion strategy and sparse based FSTM is able to provide adequate feature representations, and can achieve comparable performance with limited training samples. Experimental results on the UC Merced dataset and Google dataset of SIRI-WHU demonstrate that the proposed method can improve the performance of scene classification compared with other scene classification methods for HSR imagery.

  20. Modulation transfer function characterization and modeling of a Scophony infrared scene projector

    Science.gov (United States)

    Schildwachter, Eric F.; Boreman, Glenn D.

    1991-11-01

    A Scophony-configuration infrared scene projector, consisting of a raster-scanned CO2 laser and an acoustooptic (AO) modulator, was characterized for modulation transfer function (MTF) performance. The MTF components considered in the model were the Gaussian beam input to the AO cell, the finite aperture of the scan mirror, the width of the detector in the image plane, the transfer function of the amplifier electronics, and a term caused by Bragg-angle detuning over the bandwidth of the AM video signal driving the AO cell. The finite bandwidth of the input video signal caused a spread in the Bragg angle required for maximum diffraction efficiency. In the Scophony configuration, a collimated laser beam enters the AO cell at only one particular angle, so a falloff of diffraction efficiency (and hence MTF) resulted as the modulation frequency was increased. The Bragg-angle detuning term was found to dominate the measured system MTF.

  1. Bag of Visual Words Model with Deep Spatial Features for Geographical Scene Classification

    Directory of Open Access Journals (Sweden)

    Jiangfan Feng

    2017-01-01

    Full Text Available With the popular use of geotagging images, more and more research efforts have been placed on geographical scene classification. In geographical scene classification, valid spatial feature selection can significantly boost the final performance. Bag of visual words (BoVW can do well in selecting feature in geographical scene classification; nevertheless, it works effectively only if the provided feature extractor is well-matched. In this paper, we use convolutional neural networks (CNNs for optimizing proposed feature extractor, so that it can learn more suitable visual vocabularies from the geotagging images. Our approach achieves better performance than BoVW as a tool for geographical scene classification, respectively, in three datasets which contain a variety of scene categories.

  2. A Graphical Model for Online Auditory Scene Modulation Using EEG Evidence for Attention.

    Science.gov (United States)

    Haghighi, Marzieh; Moghadamfalahi, Mohammad; Akcakaya, Murat; Shinn-Cunningham, Barbara G; Erdogmus, Deniz

    2017-11-01

    Recent findings indicate that brain interfaces have the potential to enable attention-guided auditory scene analysis and manipulation in applications, such as hearing aids and augmented/virtual environments. Specifically, noninvasively acquired electroencephalography (EEG) signals have been demonstrated to carry some evidence regarding, which of multiple synchronous speech waveforms the subject attends to. In this paper, we demonstrate that: 1) using data- and model-driven cross-correlation features yield competitive binary auditory attention classification results with at most 20 s of EEG from 16 channels or even a single well-positioned channel; 2) a model calibrated using equal-energy speech waveforms competing for attention could perform well on estimating attention in closed-loop unbalanced-energy speech waveform situations, where the speech amplitudes are modulated by the estimated attention posterior probability distribution; 3) such a model would perform even better if it is corrected (linearly, in this instance) based on EEG evidence dependence on speech weights in the mixture; and 4) calibrating a model based on population EEG could result in acceptable performance for new individuals/users; therefore, EEG-based auditory attention classifiers may generalize across individuals, leading to reduced or eliminated calibration time and effort.

  3. Treefrogs as animal models for research on auditory scene analysis and the cocktail party problem.

    Science.gov (United States)

    Bee, Mark A

    2015-02-01

    The perceptual analysis of acoustic scenes involves binding together sounds from the same source and separating them from other sounds in the environment. In large social groups, listeners experience increased difficulty performing these tasks due to high noise levels and interference from the concurrent signals of multiple individuals. While a substantial body of literature on these issues pertains to human hearing and speech communication, few studies have investigated how nonhuman animals may be evolutionarily adapted to solve biologically analogous communication problems. Here, I review recent and ongoing work aimed at testing hypotheses about perceptual mechanisms that enable treefrogs in the genus Hyla to communicate vocally in noisy, multi-source social environments. After briefly introducing the genus and the methods used to study hearing in frogs, I outline several functional constraints on communication posed by the acoustic environment of breeding "choruses". Then, I review studies of sound source perception aimed at uncovering how treefrog listeners may be adapted to cope with these constraints. Specifically, this review covers research on the acoustic cues used in sequential and simultaneous auditory grouping, spatial release from masking, and dip listening. Throughout the paper, I attempt to illustrate how broad-scale, comparative studies of carefully considered animal models may ultimately reveal an evolutionary diversity of underlying mechanisms for solving cocktail-party-like problems in communication. Copyright © 2014 Elsevier B.V. All rights reserved.

  4. Multistep modeling (MSM) of biomolecular structure application to the A-G mispair in the B-DNA environment

    Science.gov (United States)

    Srinivasan, S.; Raghunathan, G.; Shibata, M.; Rein, R.

    1986-01-01

    A multistep modeling procedure has been evolved to study the structural changes introduced by lesions in DNA. We report here the change in the structure of regular B-DNA geometry due to the incorporation of Ganti-Aanti mispair in place of a regular G-C pair, preserving the helix continuity. The energetics of the structure so obtained is compared with the Ganti-Asyn configuration under similar constrained conditions. We present the methodology adopted and discuss the results.

  5. The denominator problem: estimating MSM-specific incidence of sexually transmitted infections and prevalence of HIV using population sizes of MSM derived from Internet surveys.

    Science.gov (United States)

    Marcus, Ulrich; Schmidt, Axel J; Kollan, Christian; Hamouda, Osamah

    2009-06-11

    Measuring prevalence and incidence of sexually transmitted infections in hard to reach populations like men who have sex with men (MSM) is hampered by unknown size and regional distribution of this population. Community sample- and study-based measurements are often fraught with participation biases and do not allow generalization of the results for other regions or the whole population group of MSM. We used the proportional regional distribution of participants of large internet-based surveys among MSM from Germany together with a general population survey-derived estimate of the MSM population to estimate regional population sizes. Based on transmission group category from surveillance data and regional MSM population size we calculated regional population-specific incidence rates of newly diagnosed HIV infection and syphilis. For HIV prevalence we compared estimates of prevalent HIV infections in MSM from a surveillance data-based model with a mixed model in which we used the proportional regional distribution of HIV positive participants from surveys and the estimated total number of prevalent HIV infections from the surveillance based model. Assuming a similar regional distribution of survey participants and the MSM population as a whole, the regional proportion of MSM in the general population can be estimated. Regional incidence calculated with the estimated MSM population as denominator and national surveillance data as numerator results in regional peak incidence rates of 7-8 per 1,000 MSM for newly diagnosed HIV infection and syphilis. The gradient between metropolitan and rural areas narrows considerably compared with calculations which use the total (male) population as denominator. Regional HIV prevalence estimates are comparable in the two models. Considering the difficulties to obtain regionally representative data by other sampling methods for MSM, in Western post-industrialized countries internet-based surveys may provide an easy and low cost tool

  6. The denominator problem: Estimating MSM-specific incidence of sexually transmitted infections and prevalence of HIV using population sizes of MSM derived from Internet surveys

    Directory of Open Access Journals (Sweden)

    Marcus Ulrich

    2009-06-01

    Full Text Available Abstract Background Measuring prevalence and incidence of sexually transmitted infections in hard to reach populations like men who have sex with men (MSM is hampered by unknown size and regional distribution of this population. Community sample – and study-based measurements are often fraught with participation biases and do not allow generalization of the results for other regions or the whole population group of MSM. Methods We used the proportional regional distribution of participants of large internet-based surveys among MSM from Germany together with a general population survey-derived estimate of the MSM population to estimate regional population sizes. Based on transmission group category from surveillance data and regional MSM population size we calculated regional population-specific incidence rates of newly diagnosed HIV infection and syphilis. For HIV prevalence we compared estimates of prevalent HIV infections in MSM from a surveillance data-based model with a mixed model in which we used the proportional regional distribution of HIV positive participants from surveys and the estimated total number of prevalent HIV infections from the surveillance based model. Results Assuming a similar regional distribution of survey participants and the MSM population as a whole, the regional proportion of MSM in the general population can be estimated. Regional incidence calculated with the estimated MSM population as denominator and national surveillance data as numerator results in regional peak incidence rates of 7–8 per 1,000 MSM for newly diagnosed HIV infection and syphilis. The gradient between metropolitan and rural areas narrows considerably compared with calculations which use the total (male population as denominator. Regional HIV prevalence estimates are comparable in the two models. Conclusion Considering the difficulties to obtain regionally representative data by other sampling methods for MSM, in Western post

  7. Sexually transmitted infections screening at HIV treatment centers for MSM can be cost-effective

    NARCIS (Netherlands)

    Vriend, Henrike J.; Lugnér, Anna K.; Xiridou, Maria; Van Der Loeff, Maarten F. Schim; Prins, Maria; De Vries, Henry J.C.; Geerlings, Suzanne E.; Prins, Jan M.; Rijnders, Bart J.A.; Van Veen, Maaike G.; Fennema, Johannes S.A.; Postma, Maarten J.; Van Der Sande, Marianne A.B.

    2013-01-01

    Objective:To estimate the cost-effectiveness of anorectal chlamydia screening among men who have sex with men (MSM) in care at HIV treatment centers. Design:Transmission model combined with economic analysis over a 20-year period. Setting and participants:MSM in care at HIV treatment centers.

  8. The development of hand-centred visual representations in the primate brain: a computer modelling study using natural visual scenes.

    Directory of Open Access Journals (Sweden)

    Juan Manuel Galeazzi

    2015-12-01

    Full Text Available Neurons that respond to visual targets in a hand-centred frame of reference have been found within various areas of the primate brain. We investigate how hand-centred visual representations may develop in a neural network model of the primate visual system called VisNet, when the model is trained on images of the hand seen against natural visual scenes. The simulations show how such neurons may develop through a biologically plausible process of unsupervised competitive learning and self-organisation. In an advance on our previous work, the visual scenes consisted of multiple targets presented simultaneously with respect to the hand. Three experiments are presented. First, VisNet was trained with computerized images consisting of a realistic image of a hand and and a variety of natural objects, presented in different textured backgrounds during training. The network was then tested with just one textured object near the hand in order to verify if the output cells were capable of building hand-centered representations with a single localised receptive field. We explain the underlying principles of the statistical decoupling that allows the output cells of the network to develop single localised receptive fields even when the network is trained with multiple objects. In a second simulation we examined how some of the cells with hand-centred receptive fields decreased their shape selectivity and started responding to a localised region of hand-centred space as the number of objects presented in overlapping locations during training increases. Lastly, we explored the same learning principles training the network with natural visual scenes collected by volunteers. These results provide an important step in showing how single, localised, hand-centered receptive fields could emerge under more ecologically realistic visual training conditions.

  9. MSM and HIV/AIDS in China.

    Science.gov (United States)

    Zhang, Bei Chuan; Chu, Quan Sheng

    2005-01-01

    This article profiles current status of spread and control of HIV/AIDS in China. China has a significant population of MSM (men who have sex with men) and they have been becoming very much alive in many ways since 1990s due to recent social changes. Some surveys indicate that great many of MSM are engaged in high-risk behaviors. In addition, majority of MSM have also experienced sexual encounters with women sometimes in their lives, which possibly contribute to spread of HIV to women. Some reports documented that HIV is becoming rampant among MSM since more than 1% of them are now infected. Political, cultural and custom elements could hinder intervention activities against HIV spread among MSM. Fortunately, many cities in China have seen that MSM were in cooperation with responsible institutions carrying out certain intervention measures. The general situation is promising. The authors forecast that the fast HIV spread among MSM of China could possibly be halted within several years when the authorities become more sensible to this issue, health service institutions offer unswerving efforts toward the MSM community and those who involve in MSM undertakes necessary responsibilities.

  10. 3-D model-based frame interpolation for distributed video coding of static scenes.

    Science.gov (United States)

    Maitre, Matthieu; Guillemot, Christine; Morin, Luce

    2007-05-01

    This paper addresses the problem of side information extraction for distributed coding of videos captured by a camera moving in a 3-D static environment. Examples of targeted applications are augmented reality, remote-controlled robots operating in hazardous environments, or remote exploration by drones. It explores the benefits of the structure-from-motion paradigm for distributed coding of this type of video content. Two interpolation methods constrained by the scene geometry, based either on block matching along epipolar lines or on 3-D mesh fitting, are first developed. These techniques are based on a robust algorithm for sub-pel matching of feature points, which leads to semi-dense correspondences between key frames. However, their rate-distortion (RD) performances are limited by misalignments between the side information and the actual Wyner-Ziv (WZ) frames due to the assumption of linear motion between key frames. To cope with this problem, two feature point tracking techniques are introduced, which recover the camera parameters of the WZ frames. A first technique, in which the frames remain encoded separately, performs tracking at the decoder and leads to significant RD performance gains. A second technique further improves the RD performances by allowing a limited tracking at the encoder. As an additional benefit, statistics on tracks allow the encoder to adapt the key frame frequency to the video motion content.

  11. The application of three-mode factor analysis (TMFA) to receptor modeling of SCENES particle data

    Science.gov (United States)

    Zeng, Yousheng; Hopke, Philip K.

    In the previous applications of eigenvector mathematical methods such as factor analysis, principal components analysis, and empirical orthogonal function analysis, the analysis has been made on a two-dimensional set of data. These data sets could be the chemical composition of a series of particle samples taken at a single location over time or the concentration of a single species measured over multiple locations at multiple times. However, there have not been methods previously available to examine a data set of chemical compositions measured at multiple sites over a series of sampling time intervals. Three-mode factor analysis permits the reduction of a three-dimensional data set into three two-dimensional matrices and a three-dimensional core matrix that presents how the system variance is partitioned among the three modes (chemical specie, location and time). The technique will be illustrated with data from the SCENES program that is measuring particle compositions at a number of sites in the southwestern United States.

  12. HPV infections among MSM in Shenzhen, China.

    Directory of Open Access Journals (Sweden)

    Dong-Yan Zhang

    Full Text Available BACKGROUND: An increasing incidence of anal cancer among men, especially men who have sex with men (MSM suggests a need to better understand anal human papillomavirus (HPV infection among this group. METHODS: A cross-sectional study was conducted among MSM in Shenzhen, China. Blood was collected for HIV serological testing and syphilis serological screening, and anal swabs were collected for HPV genotyping. Difference of HPV prevalence between HIV seropositive and HIV seronegative MSM was assessed by chi-square test. Factors associated with anal canal HPV infection were assessed by univariate and multivariate logistic regression. RESULTS: A total of 408 MSM were recruited. HIV and HPV prevalence were 6.9% and 36.4%, respectively. HPV was detected in the anal canal in 71.4% of the HIV-positive MSM and in 33.8% of the HIV-negative MSM (P<0.001. Oncogenic types were seen more often in anal specimens of HIV-positive MSM than in specimens of HIV-negative MSM (P = 0.001. The HPV genotypes detected most frequently were HPV06 (8.2%, HPV16 (7.2%, HPV11 (6.4%, HPV18 (4.7%, HPV58 (4.7%, and HPV52 (4.2%. CONCLUSIONS: In this study, HIV positive MSM had a higher burden of HPV infection, especially oncogenic HPV infection. HPV types 52 and 58 were as popular as those types designed for the currently available vaccine (HPV6, 11, 16, 18.

  13. An optimal design of magnetostrictive material (MsM) based energy harvester

    Science.gov (United States)

    Hu, Jingzhen; Yuan, Fuh-Gwo; Xu, Fujun; Huang, Alex Q.

    2010-04-01

    In this study, an optimal vibration-based energy harvesting system using magnetostrictive material (MsM) has been designed to power the Wireless Intelligent Sensor Platform (WISP), developed at North Carolina State University. A linear MsM energy harvesting device has been modeled and optimized to maximize the power output. The effects of number of MsM layers and glue layers, and load matching on the output power of the MsM energy harvester have been analyzed. From the measurement, the open circuit voltage can reach 1.5 V when the MsM cantilever beam operates at the 2nd natural frequency 324 Hz. The AC output power is 0.97 mW, giving power density 279 μW/cm3. Since the MsM device has low open circuit output voltage characteristics, a full-wave quadrupler has been designed to boost the rectified output voltage. To deliver the maximum output power to the load, a complex conjugate impedance matching between the load and the MsM device has been implemented using a discontinuous conduction mode (DCM) buck-boost converter. The maximum output power after the voltage quadrupler is now 705 μW and power density reduces to 202.4 μW/cm3, which is comparable to the piezoelectric energy harvesters given in the literature. The output power delivered to a lithium rechargeable battery is around 630 μW, independent of the load resistance.

  14. [Deficits in STI diagnosis for men who have sex with men (MSM) in German-speaking cities: results of the European MSM Internet Survey (EMIS)].

    Science.gov (United States)

    Schmidt, A J; Marcus, U

    2013-12-01

    Sexually transmitted infections (STIs) such as anal/genital warts, syphilis, and genital/rectal gonorrheal/chlamydial infections compromise the health of men who have sex with men (MSM), and increase the per-contact risk of HIV infection. Early detection of asymptomatic STIs requires regular screening including physical examinations and collection of clinical specimens that allow for the detection of infections at sites common to men's same-sex practices. From June to August 2010, the European MSM Internet Survey (EMIS) recruited 174,209 MSM from 38 European countries to an anonymous online questionnaire in 25 languages. As sexual health care for MSM in most countries is organized locally, we chose cities for comparison. Multivariable regression models were used to compare accessibility of services and applied diagnostic procedures across 1 Dutch, 1 Swiss, 1 Austrian, 3 English, and 19 German cities (N = 29,962). The proportion of respondents tested for STIs in the last 12 months in the absence of symptoms ranged from 13 % in Magdeburg to 48.0 % in Amsterdam. At a city level, low STI screening correlated with inaccessible services (R(2) = 0.72). At an individual level, anal/penile inspection and anal swabbing was most common in English cities and in Amsterdam. Compared to London, MSM in German-speaking cities had an adjusted odds ratio (AOR) of 0.06-0.20 for anal/penile inspection, and of 0.05-0.17 for anal swabbing (p < 0.001). Anal/genital warts and rectal infections are likely to be profoundly underdiagnosed among MSM in all German-speaking cities. This has implications for the sexual health of MSM, for HIV prevention, and for comparing European surveillance data. There is an urgent need to implement or improve sexual health care tailored to MSM at risk for STIs.

  15. A Neural Model of How the Brain Computes Heading from Optic Flow in Realistic Scenes

    Science.gov (United States)

    Browning, N. Andrew; Grossberg, Stephen; Mingolla, Ennio

    2009-01-01

    Visually-based navigation is a key competence during spatial cognition. Animals avoid obstacles and approach goals in novel cluttered environments using optic flow to compute heading with respect to the environment. Most navigation models try either explain data, or to demonstrate navigational competence in real-world environments without regard…

  16. On hierarchical models for visual recognition and learning of objects, scenes, and activities

    CERN Document Server

    Spehr, Jens

    2015-01-01

    In many computer vision applications, objects have to be learned and recognized in images or image sequences. This book presents new probabilistic hierarchical models that allow an efficient representation of multiple objects of different categories, scales, rotations, and views. The idea is to exploit similarities between objects and object parts in order to share calculations and avoid redundant information. Furthermore inference approaches for fast and robust detection are presented. These new approaches combine the idea of compositional and similarity hierarchies and overcome limitations of previous methods. Besides classical object recognition the book shows the use for detection of human poses in a project for gait analysis. The use of activity detection is presented for the design of environments for ageing, to identify activities and behavior patterns in smart homes. In a presented project for parking spot detection using an intelligent vehicle, the proposed approaches are used to hierarchically model...

  17. (YIP-09) Improving Synthesis and Recognition of Crowded Scenes using Statistical Models of Group Behavior

    Science.gov (United States)

    2013-05-01

    prisoner’s dilemma. In Proceedings of Florida Artifical Intelligence Research Society, pages 2–7, Day- tona Beach, FL, May 2010. [6] M. Maghami* and...A. Shah*, P. Bell*, and G. Sukthankar. A destination recommendation system for virtual worlds. In Proceedings of Florida Artifical Intelligence ...question convey? Leveraging help-seeking behavior for improved modeling in a simulation- based intelligent tutor. In Proceedings of SpringSim Military

  18. An On-line Variational Bayesian Model for Multi-Person Tracking from Cluttered Scenes

    OpenAIRE

    Ba, Sileye; Alameda-Pineda, Xavier; Xompero, Alessio; Horaud, Radu

    2016-01-01

    Object tracking is an ubiquitous problem that appears in many applications such as remote sensing, audio processing, computer vision, human-machine interfaces, human-robot interaction, etc. Although thoroughly investigated in computer vision, tracking a time-varying number of persons remains a challenging open problem. In this paper, we propose an on-line variational Bayesian model for multi-person tracking from cluttered visual observations provided by person detectors. The contributions of ...

  19. Depression and Social Stigma Among MSM in Lesotho: Implications for HIV and Sexually Transmitted Infection Prevention.

    Science.gov (United States)

    Stahlman, Shauna; Grosso, Ashley; Ketende, Sosthenes; Sweitzer, Stephanie; Mothopeng, Tampose; Taruberekera, Noah; Nkonyana, John; Baral, Stefan

    2015-08-01

    Social stigma is common among men who have sex with men (MSM) across Sub-Saharan Africa, and may influence risks for HIV and sexually transmitted infections (STIs) via its association with depression. We conducted a cross-sectional study of 530 MSM in Lesotho accrued via respondent-driven sampling. Using generalized structural equation models we examined associations between stigma, social capital, and depression with condom use and testing positive for HIV/STIs. Depression was positively associated with social stigma experienced or perceived as a result of being MSM. In contrast, increasing levels of social cohesion were negatively associated with depression. Social stigma was associated with testing positive for HIV; however, this association did not appear to be mediated by depression or condom use. These data suggest a need for integrated HIV and mental health care that addresses stigma and discrimination and facilitates positive social support for MSM.

  20. Sensing Urban Land-Use Patterns by Integrating Google Tensorflow and Scene-Classification Models

    Science.gov (United States)

    Yao, Y.; Liang, H.; Li, X.; Zhang, J.; He, J.

    2017-09-01

    With the rapid progress of China's urbanization, research on the automatic detection of land-use patterns in Chinese cities is of substantial importance. Deep learning is an effective method to extract image features. To take advantage of the deep-learning method in detecting urban land-use patterns, we applied a transfer-learning-based remote-sensing image approach to extract and classify features. Using the Google Tensorflow framework, a powerful convolution neural network (CNN) library was created. First, the transferred model was previously trained on ImageNet, one of the largest object-image data sets, to fully develop the model's ability to generate feature vectors of standard remote-sensing land-cover data sets (UC Merced and WHU-SIRI). Then, a random-forest-based classifier was constructed and trained on these generated vectors to classify the actual urban land-use pattern on the scale of traffic analysis zones (TAZs). To avoid the multi-scale effect of remote-sensing imagery, a large random patch (LRP) method was used. The proposed method could efficiently obtain acceptable accuracy (OA = 0.794, Kappa = 0.737) for the study area. In addition, the results show that the proposed method can effectively overcome the multi-scale effect that occurs in urban land-use classification at the irregular land-parcel level. The proposed method can help planners monitor dynamic urban land use and evaluate the impact of urban-planning schemes.

  1. Practical bomb scene investigation

    National Research Council Canada - National Science Library

    Thurman, James T

    2006-01-01

    .... The book also uses examples of chain of custody and scene administration forms, diagrams and tables, methods of equipment decontamination, explosives residue collection procedures and spread sheets...

  2. MSM actuators: design rules and control strategies

    Energy Technology Data Exchange (ETDEWEB)

    Holz, Benedikt; Janocha, Hartmut [Laboratory of Process Automation (LPA), Saarland University, Saarbruecken (Germany); Riccardi, Leonardo; Naso, David [Department of Electronics and Electrical Science (DEE), Politecnico di Bari (Italy)

    2012-08-15

    Magnetic shape memory (MSM) alloys are comparatively new active materials which can be used for several industrial applications, ranging from precise positioning systems to advanced robotics. Beyond the material research, which deals with the basic thermo-magneto-mechanical properties of the crystals, the design as well as the control of the actuators displacement is an essential challenge. This paper addresses those two topics, trying to give to the reader a useful overview of existing results, but also presents new ideas. First, it introduces and discusses in details some possible designs, with a special emphasis on innovative actuator design concepts which are able to exploit the particular potentialities of MSM elements. The second focus of the paper is on the problem of designing a controller, i.e., an algorithm that allows to obtain a required performance from the actuator. The proposed control strategies try to take into account two main characteristics of MSM elements: the hysteresis and the temperature dependence. The effectiveness of the strategies is emphasized by experimental results performed on a commercially available MSM actuator demonstrator. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  3. Sexual orientation- and race-based discrimination and sexual HIV risk behavior among urban MSM.

    Science.gov (United States)

    Frye, Victoria; Nandi, Vijay; Egan, James; Cerda, Magdalena; Greene, Emily; Van Tieu, Hong; Ompad, Danielle C; Hoover, Donald R; Lucy, Debbie; Baez, Eduardo; Koblin, Beryl A

    2015-02-01

    Understanding what social factors are associated with risk of HIV acquisition and transmission among gay, bisexual and other men who have sex with men (MSM) is a critical public health goal. Experiencing discrimination may increase risk of HIV infection among MSM. This analysis assessed relations between experiences of sexual orientation- and race-based discrimination and sexual HIV risk behavior among MSM in New York City. 1,369 MSM completed a self-administered computerized assessment of past 3-month sexual behavior, experience of social discrimination and other covariates. Regression models assessed relations between recent experience of discrimination and sexual HIV risk behavior. Mean age was 32 years; 32 % were white; 32 % Latino/Hispanic; 25 % African American/Black. Of MSM who self-reported HIV-positive or unknown status (377), 7 % (N = 27) reported having unprotected insertive anal intercourse with an HIV-negative or unknown status partner ("HIV transmission risk"). Of MSM who self-reported HIV-negative status (992), 11 % (110) reported unprotected receptive anal intercourse with an HIV-positive or unknown status partner ("HIV acquisition risk"). HIV acquisition risk was positively associated with sexual orientation-based discrimination in home or social neighborhoods, but not race-based discrimination. We observed that sexual orientation-based discrimination was associated with sexual HIV risk behavior among urban-dwelling MSM. Addressing environmental sources of this form of discrimination, as well as the psychological distress that may result, should be prioritized in HIV prevention efforts.

  4. The Relationship of Religiosity, Spirituality, Substance Abuse, and Depression Among Black Men Who Have Sex with Men (MSM).

    Science.gov (United States)

    Watkins, Tommie L; Simpson, Cathy; Cofield, Stacey S; Davies, Susan; Kohler, Connie; Usdan, Stuart

    2016-02-01

    HIV infection rates continue to disproportionately affect Black men who have sex with men (Black MSM) compared to other groups. Research has shown that higher rates of substance use and higher levels of depression are positively correlated with higher sexual risk behavior, and little research has examined relationships between high levels of religiosity and spirituality prevalent in Black culture and issues of substance use and depression among Black MSM. This study did just that and found a relationship between religiosity, spirituality, and risk behavior. These relationships suggest that future HIV prevention models might incorporate religiosity and spirituality to increase the efficacy of risk reduction interventions for Black MSM.

  5. Policy Changes and Improvements in Health Insurance Coverage Among MSM: 20 U.S. Cities, 2008-2014.

    Science.gov (United States)

    Cooley, Laura A; Hoots, Brooke; Wejnert, Cyprian; Lewis, Rashunda; Paz-Bailey, Gabriela

    2017-03-01

    Recent policy changes have improved the ability of gay, bisexual, and other men who have sex with men (MSM) to secure health insurance. We wanted to assess changes over time in self-reported health insurance status among MSM participating in CDC's National HIV Behavioral Surveillance (NHBS) in 2008, 2011, and 2014. We analyzed NHBS data from sexually active MSM interviewed at venues in 20 U.S. cities. To determine if interview year was associated with health insurance status, we used a Poisson model with robust standard errors. Among included MSM, the overall percentage of MSM with health insurance rose 16 % from 2008 (68 %) to 2014 (79 %) (p value for trend health insurance coverage all three interview years, by age, education, and income. Corresponding with recent policy changes, health insurance improved among MSM participating in NHBS, with greater improvements in historically underinsured demographic segments. Despite these increases, improved coverage is still needed. Improved access to health insurance could lead to a reduction in health disparities among MSM over time.

  6. Scene content is predominantly conveyed by high spatial frequencies in scene-selective visual cortex.

    Science.gov (United States)

    Berman, Daniel; Golomb, Julie D; Walther, Dirk B

    2017-01-01

    In complex real-world scenes, image content is conveyed by a large collection of intertwined visual features. The visual system disentangles these features in order to extract information about image content. Here, we investigate the role of one integral component: the content of spatial frequencies in an image. Specifically, we measure the amount of image content carried by low versus high spatial frequencies for the representation of real-world scenes in scene-selective regions of human visual cortex. To this end, we attempted to decode scene categories from the brain activity patterns of participants viewing scene images that contained the full spatial frequency spectrum, only low spatial frequencies, or only high spatial frequencies, all carefully controlled for contrast and luminance. Contrary to the findings from numerous behavioral studies and computational models that have highlighted how low spatial frequencies preferentially encode image content, decoding of scene categories from the scene-selective brain regions, including the parahippocampal place area (PPA), was significantly more accurate for high than low spatial frequency images. In fact, decoding accuracy was just as high for high spatial frequency images as for images containing the full spatial frequency spectrum in scene-selective areas PPA, RSC, OPA and object selective area LOC. We also found an interesting dissociation between the posterior and anterior subdivisions of PPA: categories were decodable from both high and low spatial frequency scenes in posterior PPA but only from high spatial frequency scenes in anterior PPA; and spatial frequency was explicitly decodable from posterior but not anterior PPA. Our results are consistent with recent findings that line drawings, which consist almost entirely of high spatial frequencies, elicit a neural representation of scene categories that is equivalent to that of full-spectrum color photographs. Collectively, these findings demonstrate the

  7. Scene content is predominantly conveyed by high spatial frequencies in scene-selective visual cortex.

    Directory of Open Access Journals (Sweden)

    Daniel Berman

    Full Text Available In complex real-world scenes, image content is conveyed by a large collection of intertwined visual features. The visual system disentangles these features in order to extract information about image content. Here, we investigate the role of one integral component: the content of spatial frequencies in an image. Specifically, we measure the amount of image content carried by low versus high spatial frequencies for the representation of real-world scenes in scene-selective regions of human visual cortex. To this end, we attempted to decode scene categories from the brain activity patterns of participants viewing scene images that contained the full spatial frequency spectrum, only low spatial frequencies, or only high spatial frequencies, all carefully controlled for contrast and luminance. Contrary to the findings from numerous behavioral studies and computational models that have highlighted how low spatial frequencies preferentially encode image content, decoding of scene categories from the scene-selective brain regions, including the parahippocampal place area (PPA, was significantly more accurate for high than low spatial frequency images. In fact, decoding accuracy was just as high for high spatial frequency images as for images containing the full spatial frequency spectrum in scene-selective areas PPA, RSC, OPA and object selective area LOC. We also found an interesting dissociation between the posterior and anterior subdivisions of PPA: categories were decodable from both high and low spatial frequency scenes in posterior PPA but only from high spatial frequency scenes in anterior PPA; and spatial frequency was explicitly decodable from posterior but not anterior PPA. Our results are consistent with recent findings that line drawings, which consist almost entirely of high spatial frequencies, elicit a neural representation of scene categories that is equivalent to that of full-spectrum color photographs. Collectively, these findings

  8. Scene Integration for Online VR Advertising Clouds

    Directory of Open Access Journals (Sweden)

    Michael Kalochristianakis

    2014-12-01

    Full Text Available This paper presents a scene composition approach that allows the combinational use of standard three dimensional objects, called models, in order to create X3D scenes. The module is an integral part of a broader design aiming to construct large scale online advertising infrastructures that rely on virtual reality technologies. The architecture addresses a number of problems regarding remote rendering for low end devices and last but not least, the provision of scene composition and integration. Since viewers do not keep information regarding individual input models or scenes, composition requires the consideration of mechanisms that add state to viewing technologies. In terms of this work we extended a well-known, open source X3D authoring tool.

  9. Baseline data from the MSM Neurocog study

    Directory of Open Access Journals (Sweden)

    T Barber

    2012-11-01

    Full Text Available We present baseline data (follow up due w24–48 from MSM Neurocog - prospective cohort study describing neurocognitive (NC function in men who have sex with men (MSM 18–50y. Objectives Describe prevalence of positive screen for NC impairment (NCI using Brief Neurocognitive Screen (BNCS; follow NC function over time. Data collected Demographics, medical history, current/nadir CD4, current/peak viral load, antiretroviral (ART use, recreational drug/tobacco/alcohol use. Subjects screen for depression (PHQ9, anxiety (GAD7, subjective memory problems (Everyday Memory Questionnaire [EMQ]. PHQ9, GAD7, EMQ, IHDS have fixed numerical cut-offs. BNCS interpreted by calculating composite z score for each subject based on distance from mean in three component tests. Comparing to population norms may overcall NCI. We used participants to construct HIV+ normal ranges after exclusion of anxiety/depression, comparing individuals to this range. 235 screened (205 HIV+, 30 HIV−. In HIV+group 59 (28.8% excluded as GAD7>10, PHQ9>15 or both (2 no data. 144 HIV+ analysed. 124 (86.1% had normal z score (within 1 SD of mean. 20 (13.9% had abnormal z: 7 (35% asymptomatic, 13 (65% symptomatic (analysed together. Not enough cognitive domains assessed by BNCS to formally diagnose HIV-related NCI. BNCS abnormals less likely to be educated at university level/beyond (40% vs. 62.1%, p=0.02 or in skilled work (45% vs. 81.5%, p<0.0001. Current/ex-recreational drug use similar (~80%; no significant association to score. All patients with abnormal z receiving ART; individual agents not associated with abnormality. IHDS correlated with abnormal BNCS (60% abnormal z had abnormal IHDS vs. 15.3% of normal, p<0.0001. No CD4 association with abnormal z (median nadir 244 in both, p=0.38. Of note, group median age was statistically different but actual difference small (normal 41y vs. abnormal 44y p<0.0001; HIV− 33y. BNCS outcome is age-related but stratification of results would

  10. The hepatitis C epidemic among HIV-positive MSM

    DEFF Research Database (Denmark)

    van der Helm, Jannie J; Prins, Maria; del Amo, Julia

    2011-01-01

    Outbreaks of acute hepatitis C virus (HCV) infection among HIV-infected MSM have been described since 2000. However, phylogenetic analysis suggests that the spread of HCV started around 1996. We estimated the incidence of HCV in HIV-infected MSM with well estimated dates of HIV seroconversion from...

  11. Imaging spectroscopy for scene analysis

    CERN Document Server

    Robles-Kelly, Antonio

    2012-01-01

    This book presents a detailed analysis of spectral imaging, describing how it can be used for the purposes of material identification, object recognition and scene understanding. The opportunities and challenges of combining spatial and spectral information are explored in depth, as are a wide range of applications. Features: discusses spectral image acquisition by hyperspectral cameras, and the process of spectral image formation; examines models of surface reflectance, the recovery of photometric invariants, and the estimation of the illuminant power spectrum from spectral imagery; describes

  12. Electrical Properties of MWCNT/HDPE Composite-Based MSM Structure Under Neutron Irradiation

    Science.gov (United States)

    Kasani, H.; Khodabakhsh, R.; Taghi Ahmadi, M.; Rezaei Ochbelagh, D.; Ismail, Razali

    2017-04-01

    Because of their low cost, low energy consumption, high performance, and exceptional electrical properties, nanocomposites containing carbon nanotubes are suitable for use in many applications such as sensing systems. In this research work, a metal-semiconductor-metal (MSM) structure based on a multiwall carbon nanotube/high-density polyethylene (MWCNT/HDPE) nanocomposite is introduced as a neutron sensor. Scanning electron microscopy, Fourier-transform infrared, and infrared spectroscopy techniques were used to characterize the morphology and structure of the fabricated device. Current-voltage ( I- V) characteristic modeling showed that the device can be assumed to be a reversed-biased Schottky diode, if the voltage is high enough. To estimate the depletion layer length of the Schottky contact, impedance spectroscopy was employed. Therefore, the real and imaginary parts of the impedance of the MSM system were used to obtain electrical parameters such as the carrier mobility and dielectric constant. Experimental observations of the MSM structure under irradiation from an americium-beryllium (Am-Be) neutron source showed that the current level in the device decreased significantly. Subsequently, current pulses appeared in situ I- V and current-time ( I- t) curve measurements when increasing voltage was applied to the MSM system. The experimentally determined depletion region length as well as the space-charge-limited current mechanism for carrier transport were compared with the range for protons calculated using Monte Carlo n-particle extended (MCNPX) code, yielding the maximum energy of recoiled protons detectable by the device.

  13. Investigating Recent Testing among MSM: Results from Community-Based HIV Rapid Testing Attendees in France

    Directory of Open Access Journals (Sweden)

    Nicolas Lorente

    2013-01-01

    Full Text Available Background. We aimed to identify factors associated with recent HIV testing in MSM who attended two experimental community-based and nonmedicalized voluntary counselling and testing programmes (CB-VCT targeting MSM in France. Methods. This analysis was based on data collected in 2009–2011 through a self-administered pretesting questionnaire. An index measuring the level of participants’ sexual orientation disclosure was built: the higher the index, the greater the disclosure. Factors associated with recent HIV testing (last test ≤ 1 year were identified using a multivariate logistic regression model adjusted for the CB-VCT programme of enrolment. Results. 716 MSM provided data on testing history. Overall, 49% were recently tested for HIV and 51% were not. Recently tested MSM had a higher homosexuality disclosure index (adjusted OR [95% confidence interval]: aOR = 1.2 [1.1–1.4], reported more inconsistent condom use during anal sex with men (aOR = 1.6 [1.2–2.1], and were less likely to have sex under the influence of club drugs (aOR = 0.6 [0.4–1.0]. Conclusion. New testing strategies should focus on those who live their homosexuality relatively secretly and those who use club drugs before sex. Governments should develop policies which encourage improved social acceptance of homosexuality as concealment of sexual orientation represents a major barrier to testing.

  14. Correlated Topic Vector for Scene Classification.

    Science.gov (United States)

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

    2017-07-01

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

  15. Young drug addicts and the drug scene.

    Science.gov (United States)

    Lucchini, R

    1985-01-01

    The drug scene generally comprises the following four distinct categories of young people: neophytes, addicts who enjoy a high status vis-à-vis other addicts, multiple drug addicts, and non-addicted drug dealers. It has its own evolution, hierarchy, structure and criteria of success and failure. The members are required to conform to the established criteria. The integration of the young addict into the drug scene is not voluntary in the real sense of the word, for he is caught between the culture that he rejects and the pseudo-culture of the drug scene. To be accepted into the drug scene, the neophyte must furnish proof of his reliability, which often includes certain forms of criminal activities. The addict who has achieved a position of importance in the drug world serves as a role model for behaviour to the neophyte. In a more advanced phase of addiction, the personality of the addict and the social functions of the drug scene are overwhelmed by the psychoactive effects of the drug, and this process results in the social withdrawal of the addict. The life-style of addicts and the subculture they develop are largely influenced by the type of drug consumed. For example, it is possible to speak of a heroin subculture and a cocaine subculture. In time, every drug scene deteriorates so that it becomes fragmented into small groups, which is often caused by legal interventions or a massive influx of new addicts. The fragmentation of the drug scene is followed by an increase in multiple drug abuse, which often aggravates the medical and social problems of drug addicts.

  16. Optimal design of a vibration-based energy harvester using magnetostrictive material (MsM)

    Science.gov (United States)

    Hu, J.; Xu, F.; Huang, A. Q.; Yuan, F. G.

    2011-01-01

    In this study, an optimal vibration-based energy harvesting system using magnetostrictive material (MsM) was designed and tested to enable the powering of a wireless sensor. In particular, the conversion efficiency, converting from magnetic to electric energy, is approximately modeled from the magnetic field induced by the beam vibration. A number of factors that affect the output power such as the number of MsM layers, coil design and load matching are analyzed and explored in the design optimization. From the measurements, the open-circuit voltage can reach 1.5 V when the MsM cantilever beam operates at the second natural frequency 324 Hz. The AC output power is 970 µW, giving a power density of 279 µW cm - 3. The attempt to use electrical reactive components (either inductors or capacitors) to resonate the system at any frequency has also been analyzed and tested experimentally. The results showed that this approach is not feasible to optimize the power. Since the MsM device has low output voltage characteristics, a full-wave quadrupler has been designed to boost the rectified output voltage. To deliver the maximum output power to the load, a complex conjugate impedance matching between the load and the MsM device is implemented using a discontinuous conduction mode (DCM) buck-boost converter. The DC output power after the voltage quadrupler reaches 705 µW and the corresponding power density is 202 µW cm - 3. The output power delivered to a lithium rechargeable battery is around 630 µW, independent of the load resistance.

  17. Influence of metal contacts on the electrical properties of a UV-MSM photodetector

    OpenAIRE

    Harzallah G.; Benmohammed Z.; Remram M.

    2013-01-01

    We have developed a two-dimensional theoretical model. This model allowed us to characterize the MSM photodetector based ZnO. It also allowed us to simulate the dark current and photocurrent of the device with different dimensions of the metal contact of structure. The simulation results were agreed with those of the experiment. We have identified the influence of geometry parameters of the metal contact on the dark current and also on the photocurrent. Calculating the ratio (photocurrent / d...

  18. Syphilis and MSM (Men Who Have Sex with Men)

    Science.gov (United States)

    ... Twitter STD on Facebook Sexually Transmitted Diseases (STDs) Syphilis & MSM (Men Who Have Sex With Men) - CDC ... Share Compartir Once nearly eliminated in the U.S., syphilis is increasing, especially among gay, bisexual, and other ...

  19. Psychological characteristics in high-risk MSM in China

    National Research Council Canada - National Science Library

    Chen, Guanzhi; Li, Yang; Zhang, Beichuan; Yu, Zengzhao; Li, Xiufang; Wang, Lixin; Yu, Ziming

    2012-01-01

    .... To date, little is known regarding the behavioral, social and psychological characteristics in Chinese MSM, which makes the implementation of preventive and therapeutic strategies for this high-risk...

  20. Psychological characteristics in high-risk MSM in China.

    Science.gov (United States)

    Chen, Guanzhi; Li, Yang; Zhang, Beichuan; Yu, Zengzhao; Li, Xiufang; Wang, Lixin; Yu, Ziming

    2012-01-20

    Men who have sex with men (MSM) have become a high-risk group of HIV infection in China. To date, little is known regarding the behavioral, social and psychological characteristics in Chinese MSM, which makes the implementation of preventive and therapeutic strategies for this high-risk subpopulation of people extremely difficult. A total of 714 questionnaires were retrieved from the database of a Chinese government-sponsored National Key Research Project titled "Risk Analysis and Strategic Prevention of HIV Transmission from MSM to the General Population in China". The respondents were categorized into a high-risk group and a control group. Their behavioral, social and psychological characteristics were comparatively analyzed. Of the 714 MSM analyzed, 59 (8.26%) had high-risk homosexual behaviors. This sub-group of MSM had a higher in-marriage rate, a higher monthly income, heavier alcohol consumption and more serious problems with sexual abuse in childhood, intentional suicide attempts and mistaken assumption on condom's role in protecting HIV infection, as compared with the control group (P discrimination (P > 0.05). A vast majority of the individuals in both behavior categories expressed support of legally protected gay clubs as well as gay marriage legislation in China. There was a strong correlation between high-risk behaviors and sexual abuse in childhood, alcohol drinking, income level and a mistaken belief in perfect HIV protection through the use of condoms. MSM with and without high-risk homosexual behaviors have different social and psychological characteristics, which should be taken into account when implementing behavioral and therapeutic interventions aimed at preventing HIV/AIDS transmission among MSM as well as from MSM to the general population in China.

  1. Psychological characteristics in high-risk MSM in China

    Directory of Open Access Journals (Sweden)

    Chen Guanzhi

    2012-01-01

    Full Text Available Abstract Background Men who have sex with men (MSM have become a high-risk group of HIV infection in China. To date, little is known regarding the behavioral, social and psychological characteristics in Chinese MSM, which makes the implementation of preventive and therapeutic strategies for this high-risk subpopulation of people extremely difficult. Methods A total of 714 questionnaires were retrieved from the database of a Chinese government-sponsored National Key Research Project titled "Risk Analysis and Strategic Prevention of HIV Transmission from MSM to the General Population in China". The respondents were categorized into a high-risk group and a control group. Their behavioral, social and psychological characteristics were comparatively analyzed. Results Of the 714 MSM analyzed, 59 (8.26% had high-risk homosexual behaviors. This sub-group of MSM had a higher in-marriage rate, a higher monthly income, heavier alcohol consumption and more serious problems with sexual abuse in childhood, intentional suicide attempts and mistaken assumption on condom's role in protecting HIV infection, as compared with the control group (P P > 0.05. A vast majority of the individuals in both behavior categories expressed support of legally protected gay clubs as well as gay marriage legislation in China. There was a strong correlation between high-risk behaviors and sexual abuse in childhood, alcohol drinking, income level and a mistaken belief in perfect HIV protection through the use of condoms. Conclusions MSM with and without high-risk homosexual behaviors have different social and psychological characteristics, which should be taken into account when implementing behavioral and therapeutic interventions aimed at preventing HIV/AIDS transmission among MSM as well as from MSM to the general population in China.

  2. Hydrological AnthropoScenes

    Science.gov (United States)

    Cudennec, Christophe

    2016-04-01

    The Anthropocene concept encapsulates the planetary-scale changes resulting from accelerating socio-ecological transformations, beyond the stratigraphic definition actually in debate. The emergence of multi-scale and proteiform complexity requires inter-discipline and system approaches. Yet, to reduce the cognitive challenge of tackling this complexity, the global Anthropocene syndrome must now be studied from various topical points of view, and grounded at regional and local levels. A system approach should allow to identify AnthropoScenes, i.e. settings where a socio-ecological transformation subsystem is clearly coherent within boundaries and displays explicit relationships with neighbouring/remote scenes and within a nesting architecture. Hydrology is a key topical point of view to be explored, as it is important in many aspects of the Anthropocene, either with water itself being a resource, hazard or transport force; or through the network, connectivity, interface, teleconnection, emergence and scaling issues it determines. We will schematically exemplify these aspects with three contrasted hydrological AnthropoScenes in Tunisia, France and Iceland; and reframe therein concepts of the hydrological change debate. Bai X., van der Leeuw S., O'Brien K., Berkhout F., Biermann F., Brondizio E., Cudennec C., Dearing J., Duraiappah A., Glaser M., Revkin A., Steffen W., Syvitski J., 2016. Plausible and desirable futures in the Anthropocene: A new research agenda. Global Environmental Change, in press, http://dx.doi.org/10.1016/j.gloenvcha.2015.09.017 Brondizio E., O'Brien K., Bai X., Biermann F., Steffen W., Berkhout F., Cudennec C., Lemos M.C., Wolfe A., Palma-Oliveira J., Chen A. C-T. Re-conceptualizing the Anthropocene: A call for collaboration. Global Environmental Change, in review. Montanari A., Young G., Savenije H., Hughes D., Wagener T., Ren L., Koutsoyiannis D., Cudennec C., Grimaldi S., Blöschl G., Sivapalan M., Beven K., Gupta H., Arheimer B., Huang Y

  3. The Rectal Mucosa and Condomless Receptive Anal Intercourse in HIV Negative MSM: Implications for HIV Transmission and Prevention

    Science.gov (United States)

    Kelley, Colleen F.; Kraft, Colleen S.; de Man, Tom J.B.; Duphare, Chandni; Lee, Hyun-Woo; Yang, Jing; Easley, Kirk A.; Tharp, Gregory K.; Mulligan, Mark J.; Sullivan, Patrick S.; Bosinger, Steven E.; Amara, Rama R.

    2016-01-01

    Most HIV transmissions among men who have sex with men (MSM), the group that accounted for 67% of new US infections in 2014, occur via exposure to the rectal mucosa. However, it is unclear how the act of condomless receptive anal intercourse (CRAI) may alter the mucosal immune environment in HIV negative MSM. Here, we performed a comprehensive characterization of the rectal mucosal immune environment for the phenotype and production of pro-inflammatory cytokines by CD4 and CD8 T cells, global transcriptomic analyses, and the composition of microbiota in HIV negative MSM. Our results show that compared to men who had never engaged in anal intercourse, the rectal mucosa of MSM engaging in CRAI has a distinct phenotype characterized by higher levels of Th17 cells, greater CD8+ T cell proliferation and production of pro-inflammatory cytokines, molecular signatures associated with mucosal injury and repair likely mediated by innate immune cells, and a microbiota enriched for the Prevotellaceae family. These data provide a high-resolution model of the immunological, molecular, and microbiological perturbations induced by CRAI, will have direct utility in understanding rectal HIV transmission among MSM, and will enhance the design of future biomedical prevention interventions, including candidate HIV vaccines. PMID:27848950

  4. Target recognition and scene interpretation in image/video understanding systems based on network-symbolic models

    Science.gov (United States)

    Kuvich, Gary

    2004-08-01

    Vision is only a part of a system that converts visual information into knowledge structures. These structures drive the vision process, resolving ambiguity and uncertainty via feedback, and provide image understanding, which is an interpretation of visual information in terms of these knowledge models. These mechanisms provide a reliable recognition if the object is occluded or cannot be recognized as a whole. It is hard to split the entire system apart, and reliable solutions to the target recognition problems are possible only within the solution of a more generic Image Understanding Problem. Brain reduces informational and computational complexities, using implicit symbolic coding of features, hierarchical compression, and selective processing of visual information. Biologically inspired Network-Symbolic representation, where both systematic structural/logical methods and neural/statistical methods are parts of a single mechanism, is the most feasible for such models. It converts visual information into relational Network-Symbolic structures, avoiding artificial precise computations of 3-dimensional models. Network-Symbolic Transformations derive abstract structures, which allows for invariant recognition of an object as exemplar of a class. Active vision helps creating consistent models. Attention, separation of figure from ground and perceptual grouping are special kinds of network-symbolic transformations. Such Image/Video Understanding Systems will be reliably recognizing targets.

  5. Automatic structural scene digitalization.

    Science.gov (United States)

    Tang, Rui; Wang, Yuhan; Cosker, Darren; Li, Wenbin

    2017-01-01

    In this paper, we present an automatic system for the analysis and labeling of structural scenes, floor plan drawings in Computer-aided Design (CAD) format. The proposed system applies a fusion strategy to detect and recognize various components of CAD floor plans, such as walls, doors, windows and other ambiguous assets. Technically, a general rule-based filter parsing method is fist adopted to extract effective information from the original floor plan. Then, an image-processing based recovery method is employed to correct information extracted in the first step. Our proposed method is fully automatic and real-time. Such analysis system provides high accuracy and is also evaluated on a public website that, on average, archives more than ten thousands effective uses per day and reaches a relatively high satisfaction rate.

  6. Recreational Drug Use among Chinese MSM and Transgender Individuals: Results from a National Online Cross-Sectional Study.

    Directory of Open Access Journals (Sweden)

    Peizhen Zhao

    Full Text Available Recreational drug use has increased considerably among Chinese men who have sex with men (MSM. The phenomenon has the potentially to increase HIV transmission among Chinese MSM. The aims of this study were: 1 to investigate the prevalence of recreational drug use among Chinese MSM, and 2 to explore the correlation between gay smartphone based sex-seeking applications (gay apps, HIV/STIs testing, group sex, commercial sex, sexual roles and poppers use among Chinese MSM.MSM who were born biologically male, were at least 16 years of age and had engaged in anal sex with a man at least once were recruited through a nation-wide online survey in 2014. Information regarding socio-demographics, risk behaviors, recreational drug use, HIV and other STIs testing history and gay app use were collected. Univariate and multivariate analysis were used to determine factors associated with recreational drug use among Chinese MSM.Among 1424 participating MSM, 1100 (77.3% reported ever using recreational drugs in their lifetime. In the last 12 months, 303 (21.3% used poppers, 34 (2.4% used crystal meth and 15 (1.0% used ecstasy. The mean age of respondents was 25.6±6.8 years, 72.9% identified as gay, 41.3% were students, and 83.8% had never been married. Multiple logistic regression models revealed that compared with non-popper users, popper users were more likely to have been tested for HIV (adjusted OR (aOR = 1.50, 95% CI: 1.15-1.96 and other STIs (aOR = 1.65, 95% CI: 1.26-2.17. In addition, popper users were more likely to engage in group sex (aOR = 2.63, 95% CI:1.80-3.86, commercial sex (aOR = 1.86, 95% CI:1.13-3.06 and used gay mobile apps to seek sexual partners (aOR = 2.10, 95% CI:1.58-2.80.Chinese MSM has a high rate of recreational drug use, including poppers. Public health programs serving MSM may consider integrating intervention programs to decrease recreational drug use related harms.

  7. Recreational Drug Use among Chinese MSM and Transgender Individuals: Results from a National Online Cross-Sectional Study.

    Science.gov (United States)

    Zhao, Peizhen; Tang, Songyuan; Wang, Cheng; Zhang, Ye; Best, John; Tangthanasup, Thitikarn May; Huang, Shujie; Yang, Bin; Wei, Chongyi; Tucker, Joseph D; Tang, Weiming

    2017-01-01

    Recreational drug use has increased considerably among Chinese men who have sex with men (MSM). The phenomenon has the potentially to increase HIV transmission among Chinese MSM. The aims of this study were: 1) to investigate the prevalence of recreational drug use among Chinese MSM, and 2) to explore the correlation between gay smartphone based sex-seeking applications (gay apps), HIV/STIs testing, group sex, commercial sex, sexual roles and poppers use among Chinese MSM. MSM who were born biologically male, were at least 16 years of age and had engaged in anal sex with a man at least once were recruited through a nation-wide online survey in 2014. Information regarding socio-demographics, risk behaviors, recreational drug use, HIV and other STIs testing history and gay app use were collected. Univariate and multivariate analysis were used to determine factors associated with recreational drug use among Chinese MSM. Among 1424 participating MSM, 1100 (77.3%) reported ever using recreational drugs in their lifetime. In the last 12 months, 303 (21.3%) used poppers, 34 (2.4%) used crystal meth and 15 (1.0%) used ecstasy. The mean age of respondents was 25.6±6.8 years, 72.9% identified as gay, 41.3% were students, and 83.8% had never been married. Multiple logistic regression models revealed that compared with non-popper users, popper users were more likely to have been tested for HIV (adjusted OR (aOR) = 1.50, 95% CI: 1.15-1.96) and other STIs (aOR = 1.65, 95% CI: 1.26-2.17). In addition, popper users were more likely to engage in group sex (aOR = 2.63, 95% CI:1.80-3.86), commercial sex (aOR = 1.86, 95% CI:1.13-3.06) and used gay mobile apps to seek sexual partners (aOR = 2.10, 95% CI:1.58-2.80). Chinese MSM has a high rate of recreational drug use, including poppers. Public health programs serving MSM may consider integrating intervention programs to decrease recreational drug use related harms.

  8. Semantic Reasoning for Scene Interpretation

    DEFF Research Database (Denmark)

    Jensen, Lars Baunegaard With; Baseski, Emre; Pugeault, Nicolas

    2008-01-01

    In this paper, we propose a hierarchical architecture for representing scenes, covering 2D and 3D aspects of visual scenes as well as the semantic relations between the different aspects. We argue that labeled graphs are a suitable representational framework for this representation and demonstrat...

  9. Advanced Techniques for Scene Analysis

    Science.gov (United States)

    2010-06-01

    example, 3D movies . The change of demand results in an attention for smooth visual quality of the reconstructed scene. In this case, visual quality of the...Vergauwen, and L. Van Gool, “Automated reconstruction of 3D scenes from sequences of images,” ISPRS Journal Of Photogrammetry And Remote Sensing, vol. 55

  10. Dynamic Frames Based Generation of 3D Scenes and Applications

    Directory of Open Access Journals (Sweden)

    Danijel Radošević

    2015-05-01

    Full Text Available Modern graphic/programming tools like Unity enables the possibility of creating 3D scenes as well as making 3D scene based program applications, including full physical model, motion, sounds, lightning effects etc. This paper deals with the usage of dynamic frames based generator in the automatic generation of 3D scene and related source code. The suggested model enables the possibility to specify features of the 3D scene in a form of textual specification, as well as exporting such features from a 3D tool. This approach enables higher level of code generation flexibility and the reusability of the main code and scene artifacts in a form of textual templates. An example of the generated application is presented and discussed.

  11. How social stigma sustains the HIV treatment gap for MSM in Mpumalanga, South Africa.

    Science.gov (United States)

    Maleke, Kabelo; Daniels, Joseph; Lane, Tim; Struthers, Helen; McIntyre, James; Coates, Thomas

    2017-11-01

    There are gaps in HIV care for men who have sex with men (MSM) in African settings, and HIV social stigma plays a significant role in sustaining these gaps. We conducted a three-year research project with 49 HIV-positive MSM in two districts in Mpumalanga Province, South Africa, to understand the factors that inform HIV care seeking behaviors. Semi-structured focus group discussions and interviews were conducted in IsiZulu, SiSwati, and some code-switching into English, and these were audio-recorded, transcribed, and translated into English. We used a constant comparison approach to analyze these data. HIV social stigma centered around gossip that sustained self-diagnosis and delayed clinical care with decisions to use traditional healers to mitigate the impact of gossip on their lives. More collaboration models are needed between traditional healers and health professionals to support the global goals for HIV testing and treatment.

  12. Neural Representation of Concurrent Harmonic Sounds in Monkey Primary Auditory Cortex: Implications for Models of Auditory Scene Analysis

    Science.gov (United States)

    Steinschneider, Mitchell; Micheyl, Christophe

    2014-01-01

    The ability to attend to a particular sound in a noisy environment is an essential aspect of hearing. To accomplish this feat, the auditory system must segregate sounds that overlap in frequency and time. Many natural sounds, such as human voices, consist of harmonics of a common fundamental frequency (F0). Such harmonic complex tones (HCTs) evoke a pitch corresponding to their F0. A difference in pitch between simultaneous HCTs provides a powerful cue for their segregation. The neural mechanisms underlying concurrent sound segregation based on pitch differences are poorly understood. Here, we examined neural responses in monkey primary auditory cortex (A1) to two concurrent HCTs that differed in F0 such that they are heard as two separate “auditory objects” with distinct pitches. We found that A1 can resolve, via a rate-place code, the lower harmonics of both HCTs, a prerequisite for deriving their pitches and for their perceptual segregation. Onset asynchrony between the HCTs enhanced the neural representation of their harmonics, paralleling their improved perceptual segregation in humans. Pitches of the concurrent HCTs could also be temporally represented by neuronal phase-locking at their respective F0s. Furthermore, a model of A1 responses using harmonic templates could qualitatively reproduce psychophysical data on concurrent sound segregation in humans. Finally, we identified a possible intracortical homolog of the “object-related negativity” recorded noninvasively in humans, which correlates with the perceptual segregation of concurrent sounds. Findings indicate that A1 contains sufficient spectral and temporal information for segregating concurrent sounds based on differences in pitch. PMID:25209282

  13. The San Francisco MSM Epidemic: A Retrospective Analysis

    Directory of Open Access Journals (Sweden)

    Brandy L. Rapatski

    2015-11-01

    Full Text Available We investigate various scenarios for ending the San Francisco MSM (men having sex with men HIV/AIDS epidemic (1978–1984. We use our previously developed model and explore changes due to prevention strategies such as testing, treatment and reduction of the number of contacts. Here we consider a “what-if” scenario, by comparing different treatment strategies, to determine which factor has the greatest impact on reducing the HIV/AIDS epidemic. The factor determining the future of the epidemic is the reproduction number R0; if R0 < 1, the epidemic is stopped. We show that treatment significantly reduces the total number of infected people. We also investigate the effect a reduction in the number of contacts after seven years, when the HIV/AIDS threat became known, would have had in the population. Both reduction of contacts and treatment alone, however, would not have been enough to bring R0 below one; but when combined, we show that the effective R0 becomes less than one, and therefore the epidemic would have been eradicated.

  14. System and method for extracting dominant orientations from a scene

    Science.gov (United States)

    Straub, Julian; Rosman, Guy; Freifeld, Oren; Leonard, John J.; Fisher, III; , John W.

    2017-05-30

    In one embodiment, a method of identifying the dominant orientations of a scene comprises representing a scene as a plurality of directional vectors. The scene may comprise a three-dimensional representation of a scene, and the plurality of directional vectors may comprise a plurality of surface normals. The method further comprises determining, based on the plurality of directional vectors, a plurality of orientations describing the scene. The determined plurality of orientations explains the directionality of the plurality of directional vectors. In certain embodiments, the plurality of orientations may have independent axes of rotation. The plurality of orientations may be determined by representing the plurality of directional vectors as lying on a mathematical representation of a sphere, and inferring the parameters of a statistical model to adapt the plurality of orientations to explain the positioning of the plurality of directional vectors lying on the mathematical representation of the sphere.

  15. Research in interactive scene analysis

    Science.gov (United States)

    Tenenbaum, J. M.; Barrow, H. G.; Weyl, S. A.

    1976-01-01

    Cooperative (man-machine) scene analysis techniques were developed whereby humans can provide a computer with guidance when completely automated processing is infeasible. An interactive approach promises significant near-term payoffs in analyzing various types of high volume satellite imagery, as well as vehicle-based imagery used in robot planetary exploration. This report summarizes the work accomplished over the duration of the project and describes in detail three major accomplishments: (1) the interactive design of texture classifiers; (2) a new approach for integrating the segmentation and interpretation phases of scene analysis; and (3) the application of interactive scene analysis techniques to cartography.

  16. Suicidal ideation among MSM in three West African countries: Associations with stigma and social capital.

    Science.gov (United States)

    Stahlman, Shauna; Grosso, Ashley; Ketende, Sosthenes; Pitche, Vincent; Kouanda, Seni; Ceesay, Nuha; Ouedraogo, Henri G; Ky-Zerbo, Odette; Lougue, Marcel; Diouf, Daouda; Anato, Simplice; Tchalla, Jules; Baral, Stefan

    2016-09-01

    Suicidal ideation is understudied among men who have sex with men (MSM) across Sub-Saharan Africa. This study aimed to explore social capital and sexual behavior stigma associated with suicidal ideation among MSM in the West African nations of The Gambia, Burkina Faso and Togo. Participants were recruited using respondent-driven sampling and snowball sampling across multiple cities (n = 1555) from July 2011 to August 2013. During a single study visit, participants completed a survey. Logistic regression models were used to assess bivariate and multivariable associations with suicidal ideation. The prevalence of lifetime suicidal ideation was 13% overall and ranged 6%-17% across study sites. After adjusting for potential confounders, MSM who reported stigma as a result of having sex with men were more likely to report suicidal ideation. Physical and sexual violence was strongly associated with suicidal ideation, including being physically harmed (adjusted odds ratio (aOR) = 2.94, 95% confidence interval (CI) = 1.91, 4.52), tortured (aOR = 3.86, 95% CI = 2.17, 6.86) and raped (aOR = 3.07, 95% CI = 2.05, 4.60). In contrast, increasing social participation with the broader community was associated with decreased report of suicidal ideation (aOR = 0.91, 95% CI = 0.85, 0.99). Sexual behavior stigma should be addressed to improve mental health among MSM in Western Sub-Saharan Africa. © The Author(s) 2016.

  17. Sex parties among urban MSM: an emerging culture and HIV risk environment.

    Science.gov (United States)

    Mimiaga, Matthew J; Reisner, Sari L; Bland, Sean E; Driscoll, Maura A; Cranston, Kevin; Isenberg, Deborah; VanDerwarker, Rodney; Mayer, Kenneth H

    2011-02-01

    Private sex parties are an emerging risk environment for HIV among men who have sex with men (MSM). In 2009, 103 participants who reported attending at least one sex party in Massachusetts in the prior 12 months completed an in-depth, interviewer-administered quantitative assessment. Multivariable logistic regression analyses were conducted to examine associations with having engaged in one or more serodiscordant unprotected anal sex (SDUAS) acts at the most recent sex party attended. Nearly one-third (32%) of the sample reported engaging in SDUAS at the most recent sex party attended. Adjusting for age, race/ethnicity, and educational attainment, variables associated with an increased odds of engaging in SDUAS at the most recent sex party were: total number of unprotected anal receptive sex acts at sex parties in the past 12 months, self-perception of being at-risk for transmitting or acquiring HIV, and sexual sensation seeking. Examined in the same model, if condoms were provided/available at the most recent sex party attended, participants were at a decreased odds of engaging in SDUAS at that sex party. The majority (80%) expressed an interest in HIV prevention activities for MSM who attend sex parties. HIV prevention interventions are needed to reach MSM who attend sex parties and should take into account individual and contextual factors that may contribute to sexual risk. Environmental factors in the sex party setting, in particular the presence and availability of condoms, may potentially mitigate individual-level factors such as unprotected anal sex.

  18. HIV Prevention Messages Targeting Young Latino Immigrant MSM

    Directory of Open Access Journals (Sweden)

    Rosa Solorio

    2014-01-01

    Full Text Available Young Latino immigrant men who have sex with men (MSM are at risk for HIV and for delayed diagnosis. A need exists to raise awareness about HIV prevention in this population, including the benefits of timely HIV testing. This project was developed through collaboration between University of WA researchers and Entre Hermanos, a community-based organization serving Latinos. Building from a community-based participatory research approach, the researchers developed a campaign that was executed by Activate Brands, based in Denver, Colorado. The authors (a describe the development of HIV prevention messages through the integration of previously collected formative data; (b describe the process of translating these messages into PSAs, including the application of a marketing strategy; (c describe testing the PSAs within the Latino MSM community; and (c determine a set of important factors to consider when developing HIV prevention messages for young Latino MSM who do not identify as gay.

  19. Race/ethnicity, education, and age are associated with engagement in ecological momentary assessment text messaging among substance-using MSM in San Francisco.

    Science.gov (United States)

    Turner, Caitlin M; Coffin, Phillip; Santos, Deirdre; Huffaker, Shannon; Matheson, Tim; Euren, Jason; DeMartini, Anna; Rowe, Chris; Batki, Steven; Santos, Glenn-Milo

    2017-04-01

    Ecological momentary assessments (EMA) are data collection approaches that characterize behaviors in real-time. However, EMA is underutilized in alcohol and substance use research among men who have sex with men (MSM). The aim of this analysis is to explore the correlates of engagement in EMA text messages among substance-using MSM in San Francisco. The present analysis uses data collected from the Project iN pilot study (n=30). Over a two-month period, participants received and responded to EMA daily text messages inquiring about their study medication, alcohol, and methamphetamine use. Baseline characteristics including demographics, alcohol use, and substance use were examined as potential correlates of engagement in EMA text messages in logistic regression and proportional hazards models. Participants had a 74% response rate to EMA text messages over the study period. MSM of color had significantly lower adjusted odds of responding to EMA texts 80% of the time or more, compared to white MSM (adjusted odds ratio=0.05, 95%CI=0.01-0.38). College-educated MSM had a lower adjusted hazard of week-long discontinuation in EMA texts (adjusted hazard ratio=0.12, 95%CI=0.02-0.63). Older MSM had a higher adjusted hazard of week-long discontinuation in EMA texts (adjusted hazard ratio=1.15, 95%CI=1.01-1.31). Differences in engagement in EMA text prompts were discovered for MSM with different racial/ethnic backgrounds, ages, and education levels. Substance use variables were not correlated with engagement in text messages, suggesting that EMA may be a useful research tool among actively substance-using MSM in San Francisco. Published by Elsevier Inc.

  20. Forensic 3D Scene Reconstruction

    Energy Technology Data Exchange (ETDEWEB)

    LITTLE,CHARLES Q.; PETERS,RALPH R.; RIGDON,J. BRIAN; SMALL,DANIEL E.

    1999-10-12

    Traditionally law enforcement agencies have relied on basic measurement and imaging tools, such as tape measures and cameras, in recording a crime scene. A disadvantage of these methods is that they are slow and cumbersome. The development of a portable system that can rapidly record a crime scene with current camera imaging, 3D geometric surface maps, and contribute quantitative measurements such as accurate relative positioning of crime scene objects, would be an asset to law enforcement agents in collecting and recording significant forensic data. The purpose of this project is to develop a feasible prototype of a fast, accurate, 3D measurement and imaging system that would support law enforcement agents to quickly document and accurately record a crime scene.

  1. Cultural differences in scene perception

    OpenAIRE

    Alotaibi, Albandari

    2016-01-01

    Do individuals from different cultures perceive scenes differently? Does culture have an influence on visual attention processes? This thesis investigates not only what these influences are, and how they affect eye movements, but also examines some of the proposed mechanisms that underlie the cultural influence in scene perception. Experiments 1 & 2 showed that Saudi participants directed a higher number of fixations to the background of images, in comparison to the British participants. Brit...

  2. Fixations on objects in natural scenes: dissociating importance from salience

    Directory of Open Access Journals (Sweden)

    Bernard Marius e’t Hart

    2013-07-01

    Full Text Available The relation of selective attention to understanding of natural scenes has been subject to intense behavioral research and computational modeling, and gaze is often used as a proxy for such attention. The probability of an image region to be fixated typically correlates with its contrast. However, this relation does not imply a causal role of contrast. Rather, contrast may relate to an object’s importance for a scene, which in turn drives attention. Here we operationalize importance by the probability that an observer names the object as characteristic for a scene. We modify luminance contrast of either a frequently named (common/important or a rarely named (rare/unimportant object, track the observers’ eye movements during scene viewing and ask them to provide keywords describing the scene immediately after.When no object is modified relative to the background, important objects draw more fixations than unimportant ones. Increases of contrast make an object more likely to be fixated, irrespective of whether it was important for the original scene, while decreases in contrast have little effect on fixations. Any contrast modification makes originally unimportant objects more important for the scene. Finally, important objects are fixated more centrally than unimportant objects, irrespective of contrast.Our data suggest a dissociation between object importance (relevance for the scene and salience (relevance for attention. If an object obeys natural scene statistics, important objects are also salient. However, when natural scene statistics are violated, importance and salience are differentially affected. Object salience is modulated by the expectation about object properties (e.g., formed by context or gist, and importance by the violation of such expectations. In addition, the dependence of fixated locations within an object on the object’s importance suggests an analogy to the effects of word frequency on landing positions in reading.

  3. Adolescent Characters and Alcohol Use Scenes in Brazilian Movies, 2000-2008.

    Science.gov (United States)

    Castaldelli-Maia, João Mauricio; de Andrade, Arthur Guerra; Lotufo-Neto, Francisco; Bhugra, Dinesh

    2016-04-01

    Quantitative structured assessment of 193 scenes depicting substance use from a convenience sample of 50 Brazilian movies was performed. Logistic regression and analysis of variance or multivariate analysis of variance models were employed to test for two different types of outcome regarding alcohol appearance: The mean length of alcohol scenes in seconds and the prevalence of alcohol use scenes. The presence of adolescent characters was associated with a higher prevalence of alcohol use scenes compared to nonalcohol use scenes. The presence of adolescents was also associated with a higher than average length of alcohol use scenes compared to the nonalcohol use scenes. Alcohol use was negatively associated with cannabis, cocaine, and other drugs use. However, when the use of cannabis, cocaine, or other drugs was present in the alcohol use scenes, a higher average length was found. This may mean that most vulnerable group may see drinking as a more attractive option leading to higher alcohol use. © The Author(s) 2016.

  4. Additional Crime Scenes for Projectile Motion Unit

    Science.gov (United States)

    Fullerton, Dan; Bonner, David

    2011-12-01

    Building students' ability to transfer physics fundamentals to real-world applications establishes a deeper understanding of underlying concepts while enhancing student interest. Forensic science offers a great opportunity for students to apply physics to highly engaging, real-world contexts. Integrating these opportunities into inquiry-based problem solving in a team environment provides a terrific backdrop for fostering communication, analysis, and critical thinking skills. One such activity, inspired jointly by the museum exhibit "CSI: The Experience"2 and David Bonner's TPT article "Increasing Student Engagement and Enthusiasm: A Projectile Motion Crime Scene,"3 provides students with three different crime scenes, each requiring an analysis of projectile motion. In this lesson students socially engage in higher-order analysis of two-dimensional projectile motion problems by collecting information from 3-D scale models and collaborating with one another on its interpretation, in addition to diagramming and mathematical analysis typical to problem solving in physics.

  5. MSM starting preexposure prophylaxis are at risk of hepatitis C virus infection

    NARCIS (Netherlands)

    Hoornenborg, Elske; Achterbergh, Roel C. A.; Schim van der Loeff, Maarten F.; Davidovich, Udi; Hogewoning, Arjan; de Vries, Henry J. C.; Schinkel, Janke; Prins, Maria; van de Laar, Thijs J. W.

    2017-01-01

    Objectives and design:Hepatitis C virus (HCV) has been recognized as an emerging sexually transmitted infection (STI) among HIV-positive MSM. However, HIV-negative MSM at high risk for HIV might also be at increased risk for HCV. We studied the HCV prevalence in HIV-negative MSM who start

  6. MSM starting preexposure prophylaxis are at risk of hepatitis C virus infection.

    NARCIS (Netherlands)

    Hoornenborg, Elske; Achterbergh, Roel C A; Schim van der Loeff, Maarten F; Davidovich, Udi; Hogewoning, Arjan; de Vries, Henry J C; Schinkel, Janke; Prins, Maria; van de Laar, Thijs J W

    2017-01-01

    Hepatitis C virus (HCV) has been recognized as an emerging sexually transmitted infection (STI) among HIV-positive MSM. However, HIV-negative MSM at high risk for HIV might also be at increased risk for HCV. We studied the HCV prevalence in HIV-negative MSM who start preexposure prophylaxis (PrEP)

  7. Crime Scenes as Augmented Reality

    DEFF Research Database (Denmark)

    Sandvik, Kjetil

    2010-01-01

    , physical damage: they are all readable and interpretable signs. As augmented reality the crime scene carries a narrative which at first is hidden and must be revealed. Due to the process of investigation and the detective's ability to reason and deduce, the crime scene as place is reconstructed as virtual......Using the concept of augmented reality, this article will investigate how places in various ways have become augmented by means of different mediatization strategies. Augmentation of reality implies an enhancement of the places' emotional character: a certain mood, atmosphere or narrative surplus...... of meaning has been implemented. This may take place at different levels, which will be presented and investigated in this article and exemplified by some cases from the fields of tourism and computer games.                       The article suggests that we may use the forensic term crime scene in order...

  8. Functional imaging of auditory scene analysis.

    Science.gov (United States)

    Gutschalk, Alexander; Dykstra, Andrew R

    2014-01-01

    Our auditory system is constantly faced with the task of decomposing the complex mixture of sound arriving at the ears into perceptually independent streams constituting accurate representations of individual sound sources. This decomposition, termed auditory scene analysis, is critical for both survival and communication, and is thought to underlie both speech and music perception. The neural underpinnings of auditory scene analysis have been studied utilizing invasive experiments with animal models as well as non-invasive (MEG, EEG, and fMRI) and invasive (intracranial EEG) studies conducted with human listeners. The present article reviews human neurophysiological research investigating the neural basis of auditory scene analysis, with emphasis on two classical paradigms termed streaming and informational masking. Other paradigms - such as the continuity illusion, mistuned harmonics, and multi-speaker environments - are briefly addressed thereafter. We conclude by discussing the emerging evidence for the role of auditory cortex in remapping incoming acoustic signals into a perceptual representation of auditory streams, which are then available for selective attention and further conscious processing. This article is part of a Special Issue entitled Human Auditory Neuroimaging. Copyright © 2013 Elsevier B.V. All rights reserved.

  9. Categorization of natural dynamic audiovisual scenes.

    Directory of Open Access Journals (Sweden)

    Olli Rummukainen

    Full Text Available This work analyzed the perceptual attributes of natural dynamic audiovisual scenes. We presented thirty participants with 19 natural scenes in a similarity categorization task, followed by a semi-structured interview. The scenes were reproduced with an immersive audiovisual display. Natural scene perception has been studied mainly with unimodal settings, which have identified motion as one of the most salient attributes related to visual scenes, and sound intensity along with pitch trajectories related to auditory scenes. However, controlled laboratory experiments with natural multimodal stimuli are still scarce. Our results show that humans pay attention to similar perceptual attributes in natural scenes, and a two-dimensional perceptual map of the stimulus scenes and perceptual attributes was obtained in this work. The exploratory results show the amount of movement, perceived noisiness, and eventfulness of the scene to be the most important perceptual attributes in naturalistically reproduced real-world urban environments. We found the scene gist properties openness and expansion to remain as important factors in scenes with no salient auditory or visual events. We propose that the study of scene perception should move forward to understand better the processes behind multimodal scene processing in real-world environments. We publish our stimulus scenes as spherical video recordings and sound field recordings in a publicly available database.

  10. Psychosocial and Behavioral Characteristics of High-Risk Men Who Have Sex with Men (MSM) of Unknown HIV Positive Serostatus in Bangkok, Thailand.

    Science.gov (United States)

    Sapsirisavat, Vorapot; Phanuphak, Nittaya; Keadpudsa, Siriwan; Egan, James E; Pussadee, Kanitta; Klaytong, Preeyarach; Reuel Friedman, M; van Griensven, Frits; Stall, Ron

    2016-12-01

    HIV prevalence remains high in men who have sex with men (MSM) in Bangkok. Even though resources for HIV testing and treatment are available for all, a large proportion of MSM still do not get HIV tested. We studied high risk MSM who are unaware of their HIV status to help maximize effectiveness of our resources. Convenience sampling was conducted among MSM who came for HIV testing at the Thai Red Cross Anonymous Clinic and two popular drop-in centers in Bangkok. Inclusion criteria were MSM aged >18 years, have not been tested positive for HIV, who reported ≥1 of the following in the previous 6 months: condomless sex with a male, being a sex worker, or having a sexual transmitted infection diagnosis. Audio-Computer-Assisted Self-Interview was used to assess psychosocial profile, sexual risks, and HIV testing patterns prior to being informed of their HIV positive status. Among 499 high-risk MSM enrolled, the median age was 24.8 years and 112 (22 %) tested HIV-positive. Among the HIV-positive participants, 92 % self-identified as gay (versus bisexual), 39 % attained a bachelors degree or higher, 65 % had monthly income 10,000-29,999 baht ($280-830 USD), 10 % had vaginal or anal sex with a woman in the past 12 months, 39 % had condomless receptive sex with men and 21 % went to Lat Phrao to find a sexual partner. Compared to HIV negative MSM, HIV-positive MSM had less HIV testing: 31 % had ever been tested for HIV, 12 % had been tested in the past 6 months; but were more likely to guess correctly their positive status (31 %). Regarding psychosocial variables among HIV-positive MSM, 7 % had regular methamphetamine use in the past 3 months, 10 % had >2 sources of discrimination, and 8 % had >2 sources of discrimination due to being MSM. In multivariable model, age2 sources of discrimination because of being MSM, did not get HIV test in past 6 months, and guess of positive HIV were significantly associated with HIV positive status. Young MSM with

  11. Multiagent architecture for scene interpretation

    Science.gov (United States)

    Ealet, Fabienne; Collin, Bertrand; Sella, G.; Garbay, Catherine

    2000-06-01

    Scene interpretation is a crucial problem for navigation and guidance systems. The necessary integration of a large variety of heterogeneous knowledge leads us to design an architecture that distributes knowledge and that performs parallel and concurrent processing. We choose a multi- agent approach which specialized agents implementation is based on incrementality, distribution, cooperation, attention mechanism and adaptability.

  12. Synchronous contextual irregularities affect early scene processing: replication and extension.

    Science.gov (United States)

    Mudrik, Liad; Shalgi, Shani; Lamy, Dominique; Deouell, Leon Y

    2014-04-01

    Whether contextual regularities facilitate perceptual stages of scene processing is widely debated, and empirical evidence is still inconclusive. Specifically, it was recently suggested that contextual violations affect early processing of a scene only when the incongruent object and the scene are presented a-synchronously, creating expectations. We compared event-related potentials (ERPs) evoked by scenes that depicted a person performing an action using either a congruent or an incongruent object (e.g., a man shaving with a razor or with a fork) when scene and object were presented simultaneously. We also explored the role of attention in contextual processing by using a pre-cue to direct subjects׳ attention towards or away from the congruent/incongruent object. Subjects׳ task was to determine how many hands the person in the picture used in order to perform the action. We replicated our previous findings of frontocentral negativity for incongruent scenes that started ~ 210 ms post stimulus presentation, even earlier than previously found. Surprisingly, this incongruency ERP effect was negatively correlated with the reaction times cost on incongruent scenes. The results did not allow us to draw conclusions about the role of attention in detecting the regularity, due to a weak attention manipulation. By replicating the 200-300 ms incongruity effect with a new group of subjects at even earlier latencies than previously reported, the results strengthen the evidence for contextual processing during this time window even when simultaneous presentation of the scene and object prevent the formation of prior expectations. We discuss possible methodological limitations that may account for previous failures to find this an effect, and conclude that contextual information affects object model selection processes prior to full object identification, with semantic knowledge activation stages unfolding only later on. Copyright © 2014 Elsevier Ltd. All rights reserved.

  13. Experiencing simultanagnosia through windowed viewing of complex social scenes.

    Science.gov (United States)

    Dalrymple, Kirsten A; Birmingham, Elina; Bischof, Walter F; Barton, Jason J S; Kingstone, Alan

    2011-01-07

    Simultanagnosia is a disorder of visual attention, defined as an inability to see more than one object at once. It has been conceived as being due to a constriction of the visual "window" of attention, a metaphor that we examine in the present article. A simultanagnosic patient (SL) and two non-simultanagnosic control patients (KC and ES) described social scenes while their eye movements were monitored. These data were compared to a group of healthy subjects who described the same scenes under the same conditions as the patients, or through an aperture that restricted their vision to a small portion of the scene. Experiment 1 demonstrated that SL showed unusually low proportions of fixations to the eyes in social scenes, which contrasted with all other participants who demonstrated the standard preferential bias toward eyes. Experiments 2 and 3 revealed that when healthy participants viewed scenes through a window that was contingent on where they looked (Experiment 2) or where they moved a computer mouse (Experiment 3), their behavior closely mirrored that of patient SL. These findings suggest that a constricted window of visual processing has important consequences for how simultanagnosic patients explore their world. Our paradigm's capacity to mimic simultanagnosic behaviors while viewing complex scenes implies that it may be a valid way of modeling simultanagnosia in healthy individuals, providing a useful tool for future research. More broadly, our results support the thesis that people fixate the eyes in social scenes because they are informative to the meaning of the scene. Copyright © 2010 Elsevier B.V. All rights reserved.

  14. ROBOT TASK SCENE ANALYZER

    Energy Technology Data Exchange (ETDEWEB)

    William R. Hamel; Steven Everett

    2000-08-01

    Environmental restoration and waste management (ER and WM) challenges in the United States Department of Energy (DOE), and around the world, involve radiation or other hazards which will necessitate the use of remote operations to protect human workers from dangerous exposures. Remote operations carry the implication of greater costs since remote work systems are inherently less productive than contact human work due to the inefficiencies/complexities of teleoperation. To reduce costs and improve quality, much attention has been focused on methods to improve the productivity of combined human operator/remote equipment systems; the achievements to date are modest at best. The most promising avenue in the near term is to supplement conventional remote work systems with robotic planning and control techniques borrowed from manufacturing and other domains where robotic automation has been used. Practical combinations of teleoperation and robotic control will yield telerobotic work systems that outperform currently available remote equipment. It is believed that practical telerobotic systems may increase remote work efficiencies significantly. Increases of 30% to 50% have been conservatively estimated for typical remote operations. It is important to recognize that the basic hardware and software features of most modern remote manipulation systems can readily accommodate the functionality required for telerobotics. Further, several of the additional system ingredients necessary to implement telerobotic control--machine vision, 3D object and workspace modeling, automatic tool path generation and collision-free trajectory planning--are existent.

  15. Trauma symptoms, internalized stigma, social support, and sexual risk behavior among HIV-positive gay and bisexual MSM who have sought sex partners online.

    Science.gov (United States)

    Burnham, Kaylee E; Cruess, Dean G; Kalichman, Moira O; Grebler, Tamar; Cherry, Chauncey; Kalichman, Seth C

    2016-01-01

    Gay, bisexual, and other men who have sex with men (MSM) remain the highest risk group for HIV infection. One reason is the increased use of the Internet to meet potential sex partners, which is associated with greater sexual risk behavior. To date, few studies have investigated psychosocial predictors of sexual risk behavior among gay and bisexual men seeking sex partners online. The purpose of the current study was to test a conceptual model of the relationships between trauma symptoms indexed on the event of HIV diagnosis, internalized HIV stigma, and social support on sexual risk behavior among gay and bisexual MSM who seek sex partners online. A sample of 142 gay and bisexual MSM recruited on- and offline completed a comprehensive online assessment battery assessing the factors noted above. A number of associations emerged; most notably internalized HIV stigma mediated the relationship between trauma-related symptoms indexed on the event of HIV diagnosis and sexual risk behavior with HIV-negative and unknown serostatus sex partners. This suggests that gay and bisexual MSM who are in greater distress over their HIV diagnosis and who are more sensitive to HIV stigma engage in more HIV transmission risk behavior. As sexual risk environments expand with the increasing use of the Internet to connect with others for sex, it is important to understand the predictors of sexual risk behavior so that tailored interventions can promote sexual health for gay and bisexual MSM seeking sex online.

  16. The Australian solar scene

    Energy Technology Data Exchange (ETDEWEB)

    Cowley, Paul [IT Power Australia (Australia)

    2007-06-15

    This presentation mainly talks about the actions taken by the Australian country concerning the use of renewable energy and the reduction of the peak load in some areas. In the first part, there are found both the geographical aspects as well as the major political, e.g. Asia-Pacific Partnership on Clean development and Climate. There are also explained the issues related to peak load growth and it is shown a comparison graphic having information about the most used photovoltaic systems. Then, there are mentioned the communities that are testing one of the model photovoltaic systems in order to: reduce the peak load, use the energy in a properly way, reduce the energy cost, among others. Finally, it is succinctly explained the photovoltaic rebate program as well as the use of the off-grid systems, besides, it is given relevant information about those remote communities of Australia and the benefits of the implementation of Bushlight. [Spanish] Esta presentacion trata primordialmente de las acciones, referentes al uso de energia renovable, tomadas por Australia y creadas con el fin de reducir la maxima demanda en algunas regiones de este pais. En la primera parte, se encuentran tanto los aspectos geograficos como los principales aspectos politicos; por ejemplo, la Sociedad Asia-Pacifico para el Desarrollo no Contaminante y el Clima. Asimismo, se da una explicacion acerca de las cuestiones relacionadas al crecimiento de la maxima demanda; ademas, se muestra un cuadro comparativo, que contiene informacion relacionada con los sistemas fotovoltaicos mas utilizados. Despues, se mencionan aquellas comunidades que tienen en periodo de prueba alguno de los modelos fotovoltaicos con el fin de: reducir la maxima demanda, utilizar eficientemente la energia, reducir el costo de la misma, entre otros aspectos mas. Finalmente, se explica escuetamente el programa de reembolso centrado en el uso de sistemas fotovoltaicos, asi como el uso de sistemas asilados de la red; ademas, se

  17. Client and provider perspectives on new HIV prevention tools for MSM in the Americas.

    Directory of Open Access Journals (Sweden)

    Sheri A Lippman

    Full Text Available Men who have sex with men (MSM in the Americas require targeted, combination HIV prevention approaches. We solicited client and provider perspectives on emerging prevention interventions including HIV pre-exposure prophylaxis (PrEP and HIV self-tests through focus groups and in-depth interviews with 130 MSM and 41 providers across four sites: New York, San Francisco, Lima, and Rio de Janeiro. Among the MSM participants, we identified three prevention typologies: non-condom users, inconsistent condom users, and consistent condom users. Northern and Southern MSM differed in the variety of harm reduction strategies utilized: where U.S. MSM relied on condom use as well as disclosure and seroadaptive behaviors for prevention, condom use without disclosure or serostatus discussions was the norm in South America. Interest in new prevention technologies was shaped by the social context. U.S. MSM preferences differed by typology, such that non-condom users were interested in taking PrEP and using home HIV tests. MSM in Brazil, regardless of typology, were interested in exploring new prevention options. MSM in Peru demonstrated moderate interest but were less comfortable with adopting new strategies. MSM and providers' opinions differed substantially with respect to new prevention options. Across sites, most providers were reticent to engage with new prevention options, though some NGO-based providers were more supportive of exploring new prevention tools. Both clients and providers will need to be engaged in developing integrated prevention strategies for MSM.

  18. PrEP awareness and decision-making for Latino MSM in San Antonio, Texas.

    Science.gov (United States)

    García, Moctezuma; Harris, Allyssa L

    2017-01-01

    Pre-Exposure Prophylaxis (PrEP) has been promoted among high-risk populations as an effective HIV biomedical intervention. However, limited research is available on the significance of culturally informed biomedical interventions for Latino MSM. A total of 159 self-administered Internet surveys were completed by Latino MSM ages 21-30 in San Antonio, Texas. The purpose of this research was to develop an instrument that measured Latino MSM attitudes and beliefs towards PrEP, identify associations between demographic factors and PrEP related factors and to suggest culturally appropriate strategies for the promotion of PrEP among the Latino MSM population. Research findings revealed implications for PrEP at the structural and individual level for Latino MSM. Structural level indicators emphasized the importance for raising PrEP awareness among Latino MSM in regards to PrEP related expenses, ameliorating stigmatization of high-risk populations, enhancing access to PrEP informed medical providers, and address mistrust of the government and medical providers role on addressing health disparities among Latino MSM. Overall, the findings for individual factors emphasize the need for patient-centered interventions for Latino MSM. Latino MSM currently on PrEP require supplemental resources to enhance PrEP adherence. Latino MSM not on PrEP require alternate options for PrEP delivery and/or cognitive behavioral approaches minimizing HIV risk behavior for Latino MSM concerned with PrEP toxicity, which may require non-biomedical interventions. Integration of Latino MSM currently on PrEP as peer educators provides a valuable resource for developing culturally informed PrEP interventions for Latino MSM. Peer educators are able to share their experiential knowledge of PrEP contextualized through cultural norms, beliefs, and values.

  19. PrEP awareness and decision-making for Latino MSM in San Antonio, Texas.

    Directory of Open Access Journals (Sweden)

    Moctezuma García

    Full Text Available Pre-Exposure Prophylaxis (PrEP has been promoted among high-risk populations as an effective HIV biomedical intervention. However, limited research is available on the significance of culturally informed biomedical interventions for Latino MSM. A total of 159 self-administered Internet surveys were completed by Latino MSM ages 21-30 in San Antonio, Texas. The purpose of this research was to develop an instrument that measured Latino MSM attitudes and beliefs towards PrEP, identify associations between demographic factors and PrEP related factors and to suggest culturally appropriate strategies for the promotion of PrEP among the Latino MSM population. Research findings revealed implications for PrEP at the structural and individual level for Latino MSM. Structural level indicators emphasized the importance for raising PrEP awareness among Latino MSM in regards to PrEP related expenses, ameliorating stigmatization of high-risk populations, enhancing access to PrEP informed medical providers, and address mistrust of the government and medical providers role on addressing health disparities among Latino MSM. Overall, the findings for individual factors emphasize the need for patient-centered interventions for Latino MSM. Latino MSM currently on PrEP require supplemental resources to enhance PrEP adherence. Latino MSM not on PrEP require alternate options for PrEP delivery and/or cognitive behavioral approaches minimizing HIV risk behavior for Latino MSM concerned with PrEP toxicity, which may require non-biomedical interventions. Integration of Latino MSM currently on PrEP as peer educators provides a valuable resource for developing culturally informed PrEP interventions for Latino MSM. Peer educators are able to share their experiential knowledge of PrEP contextualized through cultural norms, beliefs, and values.

  20. The anatomy of the crime scene

    DEFF Research Database (Denmark)

    Sandvik, Kjetil

    2010-01-01

    Crime scenes are constituted by a combination of a plot and a place. The crime scene is a place which has been in a certain state of transformation at a certain moment in time, the moment at which the place constituted the scene for some kind of criminal activity. As such the place has been encod...

  1. Multiwavelength Scophony Infrared Scene Projector

    Science.gov (United States)

    Killius, Jim; Elder, Brent; Siegel, Larry; Allweiss, Michael B.

    1990-09-01

    A Scophony Infrared Scene Projector (IRSP) is being developed for use in evaluating thermal-imaging guidance systems. The Scophony IRSP is configured to be a very high frame rate laser-scanned projection system incorporating Scophony modulation. Scophony modulation offers distinct advantages over conventional flying-spot scanning, for example, longer pixel dwell times and multiple pixel projection. The Scophony IRSP serves as the image projection system in a 'hardware in the loop' therminal-phase guidance simulation. It is capable of projecting multiband, target engagement scenarios with high fidelity using Aura's proprietary software/electronic control system. The Scophony IRSP utilizes acoustooptical (AO) devices to produce the required imagery at four separate wavelengths simultaneously. The four separate scenes are then combined and projected into the imaging guidance system.

  2. Laser scophony infrared scene project

    Science.gov (United States)

    Kircher, James R.; Marlow, Steven A.; Bastow, Michael

    1994-06-01

    A scophony infrared scene projector (IRSP) was developed by AURA Systems Inc. for use in evaluating thermal imaging guidance systems. The IRSP is a laser-scanned projector system incorporating scophony modulation with acousto-optical devices to produce multiband 96 X 96 image frames. A description of the system and preliminary test results with the Seeker Endo/Exo Demonstration Development breadboard interceptor are addressed.

  3. Sexual health of ethnic minority MSM in Britain (MESH project: design and methods

    Directory of Open Access Journals (Sweden)

    Low Nicola

    2010-07-01

    Full Text Available Abstract Background Men who have sex with men (MSM remain the group most at risk of acquiring HIV infection in Britain. HIV prevalence appears to vary widely between MSM from different ethnic minority groups in this country for reasons that are not fully understood. The aim of the MESH project was to examine in detail the sexual health of ethnic minority MSM living in Britain. Methods/Design The main objectives of the MESH project were to explore among ethnic minority MSM living in Britain: (i sexual risk behaviour and HIV prevalence; (ii their experience of stigma and discrimination; (iii disclosure of sexuality; (iv use of, and satisfaction with sexual health services; (v the extent to which sexual health services (for treatment and prevention are aware of the needs of ethnic minority MSM. The research was conducted between 2006 and 2008 in four national samples: (i ethnic minority MSM living in Britain; (ii a comparison group of white British MSM living in Britain; (iii NHS sexual health clinic staff in 15 British towns and cities with significant ethnic minority communities and; (iv sexual health promotion/HIV prevention service providers. We also recruited men from two "key migrant" groups living in Britain: MSM born in Central or Eastern Europe and MSM born in Central or South America. Internet-based quantitative and qualitative research methods were used. Ethnic minority MSM were recruited through advertisements on websites, in community venues, via informal networks and in sexual health clinics. White and "key migrant" MSM were recruited mostly through Gaydar, one of the most popular dating sites used by gay men in Britain. MSM who agreed to take part completed a questionnaire online. Ethnic minority MSM who completed the online questionnaire were asked if they would be willing to take part in an online qualitative interview using email. Service providers were identified through the British Association of Sexual Health and HIV (BASHH and

  4. Childhood Sexual Abuse Is Highly Associated With HIV Risk–Taking Behavior and Infection Among MSM in the EXPLORE Study

    Science.gov (United States)

    Mimiaga, Matthew J.; Noonan, Elizabeth; Donnell, Deborah; Safren, Steven A.; Koenen, Karestan C.; Gortmaker, Steven; O’Cleirigh, Conall; Chesney, Margaret A.; Coates, Thomas J.; Koblin, Beryl A.; Mayer, Kenneth H.

    2012-01-01

    Background Previous studies have found high rates of childhood sexual abuse (CSA) among US men who have sex with men (MSM). CSA history has been associated with a variety of negative effects later in life including behaviors that place MSM at greater risk for HIV acquisition and transmission. The present analysis is the first to examine the longitudinal association between CSA and HIV infection, unprotected anal sex, and serodiscordant unprotected anal sex, as well as mediators of these relationships among a large sample of HIV-uninfected MSM. Methods The EXPLORE Study was a behavioral intervention trial conducted in 6 US cities over 48 months with HIV infection as the primary efficacy outcome. Behavioral assessments were done every 6 months via confidential computerized assessments. Longitudinal regression models were constructed, adjusting for randomization arm, geographical location of study site, age at enrollment, education, and race/ethnicity. Results Of the 4295 participants enrolled, 39.7% had a history of CSA. Participants with a history of CSA [adjusted hazards ratio = 1.30, 95% confidence interval (CI): 1.02 to 1.69] were at increased risk for HIV infection over study follow-up. A significant association was seen between history of CSA and unprotected anal sex (adjusted odds ratio = 1.24, 95% CI: 1.12 to 1.36) and serodiscordant unprotected anal sex (adjusted odds ratio = 1.30, 95% CI: 1.18 to 1.43). Among participants reporting CSA, the EXPLORE intervention had no effect in reducing HIV infection rates. Participants reporting CSA were significantly more likely to have symptoms of depression and use nonprescription drugs. Conclusions A predictive relationship between a history of CSA and subsequent HIV infection was observed among this large sample of HIV-uninfected MSM. Findings indicate that HIV-uninfected MSM with CSA histories are at greater risk for HIV infection, report higher rates of HIV sexual risk behavior, and may derive less benefit from

  5. Social Network Support and Decreased Risk of Seroconversion in Black MSM: Results of the Brothers (HPTN 061) Study.

    Science.gov (United States)

    Hermanstyne, Keith A; Green, Harold D; Cook, Ryan; Tieu, Hong-Van; Dyer, Typhanye V; Hucks-Ortiz, Christopher; Wilton, Leo; Latkin, Carl; Shoptaw, Steven

    2018-02-07

    and SettingBlack men who have sex with men (MSM) in the United States (U.S.) have disproportionately high HIV infection rates. Social networks have been shown to influence HIV risk behavior; however, little is known about whether they affect the risk of HIV seroconversion. This study uses data from the BROTHERS (HPTN 061) study to test whether contextual factors related to social networks are associated with HIV seroconversion among black MSM.MethodsWe analyzed data from the BROTHERS study (2009-2011), which examined a multi-component intervention for black MSM in 6 U.S. cities. We ran a series of Cox regression analyses to examine associations between time-dependent measures of network support (personal/emotional, financial, medical, and social participation) and time to HIV seroconversion. We ran unadjusted models followed by models adjusted for participant age at enrollment and study location.ResultsA total of 1000 black MSM tested HIV negative at baseline and were followed at 6- and 12-month study visits. Twenty-eight men tested HIV positive. In adjusted hazard ratio models, study participants who remained HIV negative had higher proportions of social network members who provided personal/emotional (0.92 [95% CI = (0.85, 0.99)]), medical (0.92 [95% CI = (0.85, 0.99)]), or social participation (0.91 [95% CI = (0.86, 0.97)]) support.ConclusionFindings suggest that the increased presence of social network support can be protective against HIV acquisition. Future research should explore the processes that link social network support with sexual and other transmission risk behaviors as a basis to inform HIV prevention efforts.

  6. SAR Raw Data Generation for Complex Airport Scenes

    Directory of Open Access Journals (Sweden)

    Jia Li

    2014-10-01

    Full Text Available The method of generating the SAR raw data of complex airport scenes is studied in this paper. A formulation of the SAR raw signal model of airport scenes is given. Via generating the echoes from the background, aircrafts and buildings, respectively, the SAR raw data of the unified SAR imaging geometry is obtained from their vector additions. The multipath scattering and the shadowing between the background and different ground covers of standing airplanes and buildings are analyzed. Based on the scattering characteristics, coupling scattering models and SAR raw data models of different targets are given, respectively. A procedure is given to generate the SAR raw data of airport scenes. The SAR images from the simulated raw data demonstrate the validity of the proposed method.

  7. Review network for scene text recognition

    Science.gov (United States)

    Li, Shuohao; Han, Anqi; Chen, Xu; Yin, Xiaoqing; Zhang, Jun

    2017-09-01

    Recognizing text in images captured in the wild is a fundamental preprocessing task for many computer vision and machine learning applications and has gained significant attention in recent years. This paper proposes an end-to-end trainable deep review neural network for scene text recognition, which is a combination of feature extraction, feature reviewing, feature attention, and sequence recognition. Our model can generate the predicted text without any segmentation or grouping algorithm. Because the attention model in the feature attention stage lacks global modeling ability, a review network is applied to extract the global context of sequence data in the feature reviewing stage. We perform rigorous experiments across a number of standard benchmarks, including IIIT5K, SVT, ICDAR03, and ICDAR13 datasets. Experimental results show that our model is comparable to or outperforms state-of-the-art techniques.

  8. Wall grid structure for interior scene synthesis

    KAUST Repository

    Xu, Wenzhuo

    2015-02-01

    We present a system for automatically synthesizing a diverse set of semantically valid, and well-arranged 3D interior scenes for a given empty room shape. Unlike existing work on layout synthesis, that typically knows potentially needed 3D models and optimizes their location through cost functions, our technique performs the retrieval and placement of 3D models by discovering the relationships between the room space and the models\\' categories. This is enabled by a new analytical structure, called Wall Grid Structure, which jointly considers the categories and locations of 3D models. Our technique greatly reduces the amount of user intervention and provides users with suggestions and inspirations. We demonstrate the applicability of our approach on three types of scenarios: conference rooms, living rooms and bedrooms.

  9. The role of discrimination in alcohol-related problems in samples of heavy drinking HIV-negative and positive men who have sex with men (MSM).

    Science.gov (United States)

    Wray, Tyler B; Pantalone, David W; Kahler, Christopher W; Monti, Peter M; Mayer, Kenneth H

    2016-09-01

    Heavy drinking is a major public health concern among men who have sex with men (MSM), as it is in many other populations. However, the consequences of heavy drinking among MSM may be particularly severe, especially for sexual risk behavior, due to the relatively high prevalence of HIV. Minority stress models suggest that, among members of marginalized groups, discrimination may be associated with heavier alcohol use as these individuals increasingly drink to cope with such experiences. Past studies have provided some support for this association. However, they have not explored the role other drinking motives play, how these relationships might differ across MSM who are HIV-positive versus HIV-negative, or how this relationship extends to alcohol-related problems. In this study, we used path modeling to explore associations between perceived discrimination experiences, drinking motives, alcohol use, and alcohol-related problems in samples of heavy drinking MSM with and without HIV. In both HIV-negative and positive MSM, perceived discrimination was significantly positively associated with alcohol problems. Drinking to cope appears to play an important role in this relationship in both samples. Reporting more discrimination experiences was associated with drinking more frequently for sexual reasons among both groups. While the total effect of drinking to facilitate sex was positively associated with alcohol-related problems, sex motives did not mediate associations between discrimination and either drinking outcome. These results suggest that interventions addressing discrimination and specific drinking motivations may be useful in helping reduce alcohol use of heavy drinking MSM. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  10. Inferring epidemiological parameters from phylogenetic information for the HIV-1 epidemic among MSM

    Science.gov (United States)

    Quax, Rick; van de Vijver, David A. M. C.; Frentz, Dineke; Sloot, Peter M. A.

    2013-09-01

    The HIV-1 epidemic in Europe is primarily sustained by a dynamic topology of sexual interactions among MSM who have individual immune systems and behavior. This epidemiological process shapes the phylogeny of the virus population. Both fields of epidemic modeling and phylogenetics have a long history, however it remains difficult to use phylogenetic data to infer epidemiological parameters such as the structure of the sexual network and the per-act infectiousness. This is because phylogenetic data is necessarily incomplete and ambiguous. Here we show that the cluster-size distribution indeed contains information about epidemiological parameters using detailed numberical experiments. We simulate the HIV epidemic among MSM many times using the Monte Carlo method with all parameter values and their ranges taken from literature. For each simulation and the corresponding set of parameter values we calculate the likelihood of reproducing an observed cluster-size distribution. The result is an estimated likelihood distribution of all parameters from the phylogenetic data, in particular the structure of the sexual network, the per-act infectiousness, and the risk behavior reduction upon diagnosis. These likelihood distributions encode the knowledge provided by the observed cluster-size distrbution, which we quantify using information theory. Our work suggests that the growing body of genetic data of patients can be exploited to understand the underlying epidemiological process.

  11. AUTOMATIC POWERLINE SCENE CLASSIFICATION AND RECONSTRUCTION USING AIRBORNE LIDAR DATA

    Directory of Open Access Journals (Sweden)

    G. Sohn

    2012-07-01

    Full Text Available This study aims to introduce new methods for classifying key features (power lines, pylons, and buildings comprising utility corridor scene using airborne LiDAR data and modelling power lines in 3D object space. The proposed approach starts from PL scene segmentation using Markov Random Field (MRF, which emphasizes on the roles of spatial context of linear and planar features as in a graphical model. The MRF classifier identifies power line features from linear features extracted from given corridor scenes. The non-power line objects are then investigated in a planar space to sub-classify them into building and non-building class. Based on the classification results, precise localization of individual pylons is conducted through investigating a prior knowledge of contextual relations between power line and pylon. Once the pylon localization is accomplished, a power line span is identified, within which power lines are modelled with catenary curve models in 3D. Once a local catenary curve model is established, this initial model progressively extends to capture entire power line points by adopting model hypothesis and verification. The model parameters are adjusted using a stochastic non-linear square method for producing 3D power line models. An evaluation of the proposed approach is performed over an urban PL corridor area that includes a complex PL scene.

  12. Antiretroviral therapy and reasons for not taking it among men having sex with men (MSM)--results from the European MSM Internet Survey (EMIS).

    Science.gov (United States)

    Marcus, Ulrich; Hickson, Ford; Weatherburn, Peter; Furegato, Martina; Breveglieri, Michele; Berg, Rigmor C; Schmidt, Axel J

    2015-01-01

    The preventive effects of antiretroviral treatment (ART) on onward transmission of HIV are a major reason for broadening eligibility for ART. In the WHO European Region, surveillance reveals substantial differences in access to ART across regions and sub-populations. We analysed self-reported data on ART and reasons for not taking ART from EMIS, a large Pan-European Internet survey among men-who-have-sex-with-men (MSM). Respondents from 38 European countries reported their last HIV test result and, if diagnosed with HIV, their treatment status, and reasons for not taking or having stopped ART from a 7 item multiple choice list and/ or answered an open-ended question to give other reasons. Responses were classified as fear of consequences, perceived lack of need, and ART inaccessibility based on factor analysis. Associations between not taking ART because of fear of consequences, and demographic, behavioural and contextual indicators were identified in a multivariable regression model. 13,353 (7.7%) of 174,209 respondents had been diagnosed with HIV. Among them 3,391 (25.4%) had never received ART, and 278 (2.1%) had stopped taking ART. Perceived lack of need was by far the most common reason for not taking or stopping ART (mentioned by 3259 (88.8%) respondents), followed by fear of consequences (428 (11.7%)), and ART inaccessibility (86 (2.3%)). For all reasons, an East-West gradient could be seen, with larger proportions of men living in Central and Eastern Europe reporting reasons other than medical advice for not taking ART. A minority of men were reluctant to start ART independent of medical advice and this was associated with experiences of discrimination in health care systems. ART is widely available for MSM diagnosed with HIV across Europe. Not being on treatment is predominantly due to treatment not being recommended by their physician and/or not perceived to be needed by the respondent.

  13. PrEP awareness and decision-making for Latino MSM in San Antonio, Texas

    OpenAIRE

    García, Moctezuma; Harris, Allyssa L.

    2017-01-01

    Pre-Exposure Prophylaxis (PrEP) has been promoted among high-risk populations as an effective HIV biomedical intervention. However, limited research is available on the significance of culturally informed biomedical interventions for Latino MSM. A total of 159 self-administered Internet surveys were completed by Latino MSM ages 21–30 in San Antonio, Texas. The purpose of this research was to develop an instrument that measured Latino MSM attitudes and beliefs towards PrEP, identify associatio...

  14. Randomized Probabilistic Latent Semantic Analysis for Scene Recognition

    Science.gov (United States)

    Rodner, Erik; Denzler, Joachim

    The concept of probabilistic Latent Semantic Analysis (pLSA) has gained much interest as a tool for feature transformation in image categorization and scene recognition scenarios. However, a major issue of this technique is overfitting. Therefore, we propose to use an ensemble of pLSA models which are trained using random fractions of the training data. We analyze empirically the influence of the degree of randomization and the size of the ensemble on the overall classification performance of a scene recognition task. A thoughtful evaluation shows the benefits of this approach compared to a single pLSA model.

  15. Video Pedestrian Detection Based on Orthogonal Scene Motion Pattern

    Directory of Open Access Journals (Sweden)

    Jianming Qu

    2014-01-01

    Full Text Available In fixed video scenes, scene motion patterns can be a very useful prior knowledge for pedestrian detection which is still a challenge at present. A new approach of cascade pedestrian detection using an orthogonal scene motion pattern model in a general density video is developed in this paper. To statistically model the pedestrian motion pattern, a probability grid overlaying the whole scene is set up to partition the scene into paths and holding areas. Features extracted from different pattern areas are classified by a group of specific strategies. Instead of using a unitary classifier, the employed classifier is composed of two directional subclassifiers trained, respectively, with different samples which are selected by two orthogonal directions. Considering that the negative images from the detection window scanning are much more than the positive ones, the cascade AdaBoost technique is adopted by the subclassifiers to reduce the negative image computations. The proposed approach is proved effectively by static classification experiments and surveillance video experiments.

  16. Radio Wave Propagation Scene Partitioning for High-Speed Rails

    Directory of Open Access Journals (Sweden)

    Bo Ai

    2012-01-01

    Full Text Available Radio wave propagation scene partitioning is necessary for wireless channel modeling. As far as we know, there are no standards of scene partitioning for high-speed rail (HSR scenarios, and therefore we propose the radio wave propagation scene partitioning scheme for HSR scenarios in this paper. Based on our measurements along the Wuhan-Guangzhou HSR, Zhengzhou-Xian passenger-dedicated line, Shijiazhuang-Taiyuan passenger-dedicated line, and Beijing-Tianjin intercity line in China, whose operation speeds are above 300 km/h, and based on the investigations on Beijing South Railway Station, Zhengzhou Railway Station, Wuhan Railway Station, Changsha Railway Station, Xian North Railway Station, Shijiazhuang North Railway Station, Taiyuan Railway Station, and Tianjin Railway Station, we obtain an overview of HSR propagation channels and record many valuable measurement data for HSR scenarios. On the basis of these measurements and investigations, we partitioned the HSR scene into twelve scenarios. Further work on theoretical analysis based on radio wave propagation mechanisms, such as reflection and diffraction, may lead us to develop the standard of radio wave propagation scene partitioning for HSR. Our work can also be used as a basis for the wireless channel modeling and the selection of some key techniques for HSR systems.

  17. Research on hyperspectral dynamic scene and image sequence simulation

    Science.gov (United States)

    Sun, Dandan; Gao, Jiaobo; Sun, Kefeng; Hu, Yu; Li, Yu; Xie, Junhu; Zhang, Lei

    2016-10-01

    This paper presents a simulation method of hyper-spectral dynamic scene and image sequence for hyper-spectral equipment evaluation and target detection algorithm. Because of high spectral resolution, strong band continuity, anti-interference and other advantages, in recent years, hyper-spectral imaging technology has been rapidly developed and is widely used in many areas such as optoelectronic target detection, military defense and remote sensing systems. Digital imaging simulation, as a crucial part of hardware in loop simulation, can be applied to testing and evaluation hyper-spectral imaging equipment with lower development cost and shorter development period. Meanwhile, visual simulation can produce a lot of original image data under various conditions for hyper-spectral image feature extraction and classification algorithm. Based on radiation physic model and material characteristic parameters this paper proposes a generation method of digital scene. By building multiple sensor models under different bands and different bandwidths, hyper-spectral scenes in visible, MWIR, LWIR band, with spectral resolution 0.01μm, 0.05μm and 0.1μm have been simulated in this paper. The final dynamic scenes have high real-time and realistic, with frequency up to 100 HZ. By means of saving all the scene gray data in the same viewpoint image sequence is obtained. The analysis results show whether in the infrared band or the visible band, the grayscale variations of simulated hyper-spectral images are consistent with the theoretical analysis results.

  18. Hepatitis A outbreak in HIV-infected MSM and in PrEP-using MSM despite a high level of immunity, Lyon, France, January to June 2017

    Science.gov (United States)

    Charre, Caroline; Ramière, Christophe; Roque-Afonso, Anne-Marie; Chidiac, Christian; Zoulim, Fabien; Godinot, Matthieu; Koffi, Joseph; Scholtès, Caroline; Livrozet, Jean-Michel; Cotte, Laurent

    2017-01-01

    Since 2016, an increase in the number of hepatitis A cases affecting mainly men who have sex with men (MSM) has been reported in low endemic countries in Europe. We calculated the attack rate in Lyon, France, in populations considered at high-risk: HIV-infected MSM and HIV-negative MSM receiving HIV pre-exposure prophylaxis (PrEP). In these populations, high level of immunity did not prevent the outbreak, indicating that vaccination should be reinforced, particularly in younger individuals. PMID:29208161

  19. Finding edges in noisy scenes

    Science.gov (United States)

    Machuca, R.; Gilbert, A. L.

    1981-01-01

    Edge detection in the presence of noise is a well-known problem. This paper examines an applications-motivated approach for solving the problem using novel techniques and presents a method developed by the authors that performs well on a large class of targets. ROC curves are used to compare this method with other well-known edge detection operators, with favorable results. A theoretical argument is presented that favors LMMSE filtering over median filtering in extremely noisy scenes. Simulated results of the research are presented.

  20. 3D scene reconstruction based on 3D laser point cloud combining UAV images

    Science.gov (United States)

    Liu, Huiyun; Yan, Yangyang; Zhang, Xitong; Wu, Zhenzhen

    2016-03-01

    It is a big challenge capturing and modeling 3D information of the built environment. A number of techniques and technologies are now in use. These include GPS, and photogrammetric application and also remote sensing applications. The experiment uses multi-source data fusion technology for 3D scene reconstruction based on the principle of 3D laser scanning technology, which uses the laser point cloud data as the basis and Digital Ortho-photo Map as an auxiliary, uses 3DsMAX software as a basic tool for building three-dimensional scene reconstruction. The article includes data acquisition, data preprocessing, 3D scene construction. The results show that the 3D scene has better truthfulness, and the accuracy of the scene meet the need of 3D scene construction.

  1. Young, Online and in the Dark: Scaling Up HIV Testing among MSM in ASEAN.

    Science.gov (United States)

    Guadamuz, Thomas E; Cheung, Doug H; Wei, Chongyi; Koe, Stuart; Lim, Sin How

    2015-01-01

    Poor HIV testing uptake by MSM may be attributable to unique challenges that are localized in Southeast Asia. To characterize MSM who never tested for HIV, to identify correlates of never testing, and to elucidate the perceived barriers to HIV testing. The present study used data from the Asian Internet MSM Sex Survey (AIMSS) and restricted the analysis to 4,310 MSM from the ten member countries of the Association of South East Asian Nations (ASEAN). Among MSM participants from ASEAN in our sample, 1290 (29.9%) reported having never been tested for HIV, 471 (10.9%) tested for HIV more than 2 years ago, and 2186 (50.7%) reported their last test date was between 6 months and two years ago, with only 363 (8.4%) of these men having been tested in the past 6 months. In multivariable logistic regression, younger MSM (age 15-22 years old [AOR: 4.60, 95% CI: 3.04-6.96]), MSM with lower education (secondary school or lower [AOR: 1.37, 95% CI: 1.03-1.83]), MSM who identify as bisexual or heterosexual (compared to gay-identified) (AOR: 1.94, 95% CI: 1.60-2.35), and MSM who had never used a condom with male partners (AOR: 1.61, 95% CI: 1.32-1.97) had higher odds of never been HIV tested. Main reason for not being tested was a low risk perception of HIV exposure (n = 390, 30.2%). Current HIV prevention response must not leave MSM "in the dark," but instead meet them where they are by utilizing the Internet creatively through social media and smart phones. As ASEAN Economic Community (AEC) is quickly becoming a reality, so must there be an equally fast and united response to slowing down the HIV epidemics among MSM in ASEAN.

  2. Young, Online and in the Dark: Scaling Up HIV Testing among MSM in ASEAN.

    Directory of Open Access Journals (Sweden)

    Thomas E Guadamuz

    Full Text Available Poor HIV testing uptake by MSM may be attributable to unique challenges that are localized in Southeast Asia.To characterize MSM who never tested for HIV, to identify correlates of never testing, and to elucidate the perceived barriers to HIV testing.The present study used data from the Asian Internet MSM Sex Survey (AIMSS and restricted the analysis to 4,310 MSM from the ten member countries of the Association of South East Asian Nations (ASEAN.Among MSM participants from ASEAN in our sample, 1290 (29.9% reported having never been tested for HIV, 471 (10.9% tested for HIV more than 2 years ago, and 2186 (50.7% reported their last test date was between 6 months and two years ago, with only 363 (8.4% of these men having been tested in the past 6 months. In multivariable logistic regression, younger MSM (age 15-22 years old [AOR: 4.60, 95% CI: 3.04-6.96], MSM with lower education (secondary school or lower [AOR: 1.37, 95% CI: 1.03-1.83], MSM who identify as bisexual or heterosexual (compared to gay-identified (AOR: 1.94, 95% CI: 1.60-2.35, and MSM who had never used a condom with male partners (AOR: 1.61, 95% CI: 1.32-1.97 had higher odds of never been HIV tested. Main reason for not being tested was a low risk perception of HIV exposure (n = 390, 30.2%.Current HIV prevention response must not leave MSM "in the dark," but instead meet them where they are by utilizing the Internet creatively through social media and smart phones. As ASEAN Economic Community (AEC is quickly becoming a reality, so must there be an equally fast and united response to slowing down the HIV epidemics among MSM in ASEAN.

  3. Emergence of visual saliency from natural scenes via context-mediated probability distributions coding.

    Directory of Open Access Journals (Sweden)

    Jinhua Xu

    Full Text Available Visual saliency is the perceptual quality that makes some items in visual scenes stand out from their immediate contexts. Visual saliency plays important roles in natural vision in that saliency can direct eye movements, deploy attention, and facilitate tasks like object detection and scene understanding. A central unsolved issue is: What features should be encoded in the early visual cortex for detecting salient features in natural scenes? To explore this important issue, we propose a hypothesis that visual saliency is based on efficient encoding of the probability distributions (PDs of visual variables in specific contexts in natural scenes, referred to as context-mediated PDs in natural scenes. In this concept, computational units in the model of the early visual system do not act as feature detectors but rather as estimators of the context-mediated PDs of a full range of visual variables in natural scenes, which directly give rise to a measure of visual saliency of any input stimulus. To test this hypothesis, we developed a model of the context-mediated PDs in natural scenes using a modified algorithm for independent component analysis (ICA and derived a measure of visual saliency based on these PDs estimated from a set of natural scenes. We demonstrated that visual saliency based on the context-mediated PDs in natural scenes effectively predicts human gaze in free-viewing of both static and dynamic natural scenes. This study suggests that the computation based on the context-mediated PDs of visual variables in natural scenes may underlie the neural mechanism in the early visual cortex for detecting salient features in natural scenes.

  4. Adaptively Combining Local with Global Information for Natural Scenes Categorization

    Science.gov (United States)

    Liu, Shuoyan; Xu, De; Yang, Xu

    This paper proposes the Extended Bag-of-Visterms (EBOV) to represent semantic scenes. In previous methods, most representations are bag-of-visterms (BOV), where visterms referred to the quantized local texture information. Our new representation is built by introducing global texture information to extend standard bag-of-visterms. In particular we apply the adaptive weight to fuse the local and global information together in order to provide a better visterm representation. Given these representations, scene classification can be performed by pLSA (probabilistic Latent Semantic Analysis) model. The experiment results show that the appropriate use of global information improves the performance of scene classification, as compared with BOV representation that only takes the local information into account.

  5. Validation of the ‘Drinking Expectancy Questionnaire for Men Who Have Sex with Men’ (DEQ-MSM) in Peru

    Science.gov (United States)

    Vagenas, Panagiotis; Wickersham, Jeffrey A.; Calabrese, Sarah K.; Lama, Javier R.; Benites, Carlos M.; Pun, Monica; Sanchez, Jorge; Altice, Frederick L.

    2016-01-01

    Introduction and Aims Alcohol use disorders are highly prevalent among men who have sex with men (MSM) in Peru where the HIV epidemic is concentrated 100-fold greater among MSM, than in the general population. Drinking expectancies have been associated with the intent to drink and engage in high-risk behaviors. Assessing them in this population may uncover attractive intervention targets that in turn can be used to reduce problematic drinking and risky sexual behaviors. The drinking expectancy questionnaire for MSM (DEQ-MSM) was developed to accurately measure drinking expectancies, specifically among MSM. This study aimed to validate this instrument for the first time in Spanish, in South America and among MSM in Peru. Design and Methods To validate the DEQ-MSM among Spanish-speaking MSM in Peru, we used exploratory and confirmatory factor analysis in a sample of 5,148 MSM, including 700 transgender women (TGW). Results Exploratory factor analysis showed a 2-factor structure to the Spanish version of the DEQ-MSM (DEQ-MSM-S), which was similar for MSM and TGW. The reliability of the translated DEQ-MSM was excellent (α=0.91). Discussion and Conclusions The DEQ-MSM-S was shown to be highly reliable in a large population of Peruvian MSM and TGW. This short instrument can be effectively integrated into research or clinical practice, in order to identify alcohol-consuming, high-risk MSM, who can then be directed for further screening and/or intervention. Future research should aim to associate the Spanish version of the DEQ-MSM with risky sexual behaviors among this population, in order to identify potential intervention targets. PMID:26120824

  6. Scene and object vision in rats.

    Science.gov (United States)

    Simpson, E L; Gaffan, E A

    1999-02-01

    Dark Agouti rats learned to discriminate large visual displays ("scenes") in a computer-controlled Y-maze. Each scene comprised several shapes ("objects") against a contrasting background. The constant-negative paradigm was used; in each problem, one constant scene was presented on every trial together with a trial-unique variable scene, and rats were rewarded for approaching the variable scene. By varying the manner in which variables differed from the constant, we investigated what aspects of scenes and the objects comprising them were salient. In Experiment 1, rats discriminated constant scenes more easily if they contained four objects rather than six, and they showed a slight attentional bias towards the lower halves of the screens. That bias disappeared in Experiment 2. Experiments 3 and 4 showed that rats could discriminate scenes even if the objects that comprised them were closely matched in position, luminance, and area. Therefore, they encoded the form of individual objects. Rats perceived shapes of the same class (e.g. two ellipses) as more similar than shapes from different classes (e.g. ellipse and polygon) regardless of whether they also differed in area. This paradigm is suitable for studying the neuropsychology of perceiving spatial relationships in multi-object scenes and of identifying visual objects.

  7. Audiovisual integration facilitates unconscious visual scene processing.

    Science.gov (United States)

    Tan, Jye-Sheng; Yeh, Su-Ling

    2015-10-01

    Meanings of masked complex scenes can be extracted without awareness; however, it remains unknown whether audiovisual integration occurs with an invisible complex visual scene. The authors examine whether a scenery soundtrack can facilitate unconscious processing of a subliminal visual scene. The continuous flash suppression paradigm was used to render a complex scene picture invisible, and the picture was paired with a semantically congruent or incongruent scenery soundtrack. Participants were asked to respond as quickly as possible if they detected any part of the scene. Release-from-suppression time was used as an index of unconscious processing of the complex scene, which was shorter in the audiovisual congruent condition than in the incongruent condition (Experiment 1). The possibility that participants adopted different detection criteria for the 2 conditions was excluded (Experiment 2). The audiovisual congruency effect did not occur for objects-only (Experiment 3) and background-only (Experiment 4) pictures, and it did not result from consciously mediated conceptual priming (Experiment 5). The congruency effect was replicated when catch trials without scene pictures were added to exclude participants with high false-alarm rates (Experiment 6). This is the first study demonstrating unconscious audiovisual integration with subliminal scene pictures, and it suggests expansions of scene-perception theories to include unconscious audiovisual integration. (c) 2015 APA, all rights reserved).

  8. Experiences of Black MSM at an HBCU Regarding Stigma and HIV Risk Behavior

    Science.gov (United States)

    Jeter, Natasha Harden

    2016-01-01

    Black men who have sex with men (MSM) on Historically Black College/University (HBCU) campuses face a unique set of challenges. In addition to being disproportionately affected by HIV, Black MSM are impacted by risk behavior, stigma, and environmental policies and practices that adversely influence their experiences. The purpose of this study was…

  9. The hepatitis C epidemic among HIV-positive MSM: incidence estimates from 1990 to 2007

    NARCIS (Netherlands)

    van der Helm, Jannie J.; Prins, Maria; del Amo, Julia; Bucher, Heiner C.; Chêne, Geneviève; Dorrucci, Maria; Gill, John; Hamouda, Osamah; Sannes, Mette; Porter, Kholoud; Geskus, Ronald B.; Meyer, Laurence; Pillay, Deenan; Rosinska, Magda; Sabin, Caroline; Touloumi, Giota; Lodi, Sara; Coughlin, Kate; Walker, Sarah; Babiker, Abdel; de Luca, Andrea; Fisher, Martin; Muga, Roberto; Zangerle, Robert; Kelleher, Tony; Ramacciotti, Tim; Gelgor, Linda; Cooper, David; Smith, Don; Bruun Jørgensen, Louise; Nielsen, Claus; Pedersen, Court; Lutsar, Irja; Dabis, Francois; Thiebaut, Rodolphe; Masquelier, Bernard; Costagliola, Dominique; Guiguet, Marguerite; Vanhems, Philippe; Chaix, Marie-Laure; Ghosn, Jade; Boufassa, Faroudy; Kücherer, Claudia; Bartmeyer, Barbara; Pantazis, Nikos; Hatzakis, Angelos; Paraskevis, Dimitrios; Karafoulidou, Anastasia; Rezza, Giovanni; Balotta, Claudia; D'Arminio Monforte, Antonella; Cozzi-Lepri, Alessandro; Schuitemaker, Hanneke; Brubakk, Oddbjorn; Kran, Anne-Marte B.; Rosinska, Magdalena; Tor, Jordi; de Olalla, Patricia G.; Cayla, Joan; del Romero, Jorge; Pérez-Hoyos, Santiago; Rickenbach, Martin; Francioli, Patrick; Malyuta, Ruslan; Brettle, Ray; Murphy, Gary; Johnson, Anne; Phillips, Andrew; Delpech, Valerie; Jaffe, Harold; Morrison, Charles; Salata, Robert; Mugerwa, Roy; Chipato, Tsungai; Amornkul, Pauli

    2011-01-01

    Outbreaks of acute hepatitis C virus (HCV) infection among HIV-infected MSM have been described since 2000. However, phylogenetic analysis suggests that the spread of HCV started around 1996. We estimated the incidence of HCV in HIV-infected MSM with well estimated dates of HIV seroconversion from

  10. Stable incidence of HIV diagnoses among Danish MSM despite increased engagement in unsafe sex

    DEFF Research Database (Denmark)

    Cowan, Susan Alice; Gerstoft, Jan; Haff, Jakob

    2012-01-01

    Since introduction of highly active antiretroviral therapy (HAART), the prevalence of Danish HIV-positive men who have sex with men (MSM) has increased substantially. In contrast, the incidence of MSM diagnosed with HIV has not increased, and this paradox has been the focus of intensive debate....

  11. Semi-Supervised Multitask Learning for Scene Recognition.

    Science.gov (United States)

    Lu, Xiaoqiang; Li, Xuelong; Mou, Lichao

    2015-09-01

    Scene recognition has been widely studied to understand visual information from the level of objects and their relationships. Toward scene recognition, many methods have been proposed. They, however, encounter difficulty to improve the accuracy, mainly due to two limitations: 1) lack of analysis of intrinsic relationships across different scales, say, the initial input and its down-sampled versions and 2) existence of redundant features. This paper develops a semi-supervised learning mechanism to reduce the above two limitations. To address the first limitation, we propose a multitask model to integrate scene images of different resolutions. For the second limitation, we build a model of sparse feature selection-based manifold regularization (SFSMR) to select the optimal information and preserve the underlying manifold structure of data. SFSMR coordinates the advantages of sparse feature selection and manifold regulation. Finally, we link the multitask model and SFSMR, and propose the semi-supervised learning method to reduce the two limitations. Experimental results report the improvements of the accuracy in scene recognition.

  12. Eye Movement Control during Scene Viewing: Immediate Effects of Scene Luminance on Fixation Durations

    Science.gov (United States)

    Henderson, John M.; Nuthmann, Antje; Luke, Steven G.

    2013-01-01

    Recent research on eye movements during scene viewing has primarily focused on where the eyes fixate. But eye fixations also differ in their durations. Here we investigated whether fixation durations in scene viewing are under the direct and immediate control of the current visual input. Subjects freely viewed photographs of scenes in preparation…

  13. Latent class analysis of substance use among men who have sex with men in Malaysia: Findings from the Asian Internet MSM Sex Survey.

    Science.gov (United States)

    Lim, Sin How; Cheung, Doug H; Guadamuz, Thomas E; Wei, Chongyi; Koe, Stuart; Altice, Frederick L

    2015-06-01

    High prevalence of substance use among men who have sex with men (MSM) may drive the HIV epidemic in Malaysia but patterns of substance use among Malaysian MSM have not been examined. Our study investigated specific Malaysian MSM risk groups to determine the association between their substance use and sexual risk behaviors. Data from Malaysian respondents (n=1235) in a large, multinational online survey of Asian MSM in 2010 were used to identify latent classes of substance use. Subsequent covariates were included in a joint model to predict class membership. The 3-class model was identified as the best fitting model, which included: (1) 'negligible substance use' for those reporting none or using any substance sparingly; (2) 'soft substance use' for those using poppers, ecstasy and drinking before sex; and (3) 'amphetamine-type stimulant (ATS) use' for those using stimulants (methamphetamine, ecstasy), erectile dysfunction drugs and recreational drug use before sex. Men in the 'ATS use' category were significantly less likely to not know their HIV status (AOR: 0.30, 95%CI: 0.14,0.66), more likely to have had more than 6 male sex partners (AOR: 4.83, 95% CI: 1.92-12.2), to have group sex (AOR:4.07, 95% CI: 2.31-7.15), to report inconsistent condom use (AOR:2.01, 95% CI: 1.12-3.60), to be HIV-infected (AOR:3.92, 95% CI: 1.63-8.42) and to have had any sexually transmitted infections (AOR:3.92, 95% CI:1.70, 9.08), compared to men in the 'negligible substance use' category. Our study identified subgroups of Malaysian MSM with distinct substance use patterns and HIV-related risk profiles, which provides implication for targeting HIV prevention in this subpopulation. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  14. HPV vaccine acceptability in HIV-infected and HIV negative men who have sex with men (MSM) in Ireland

    OpenAIRE

    C. Sadlier; Lynam, A.; O'Dea, S; Delamere, S.; Quinlan, M.; Clarke, S.; Sheils, O; Bergin, C.

    2016-01-01

    Background Men who have sex with men (MSM), particularly HIV-infected MSM are disproportionately affected by HPV infection and associated disease. The HPV vaccine has potential to greatly reduce the burden of HPV-associated disease including anal cancer in MSM. The efficacy of the HPV vaccine is dependent on high levels of vaccine uptake. The aim of this study was to examine HPV vaccine acceptability and factors influencing vaccine acceptability in MSM in Ireland. Methods A self-administered ...

  15. Intimacy motivations and pre-exposure prophylaxis (PrEP) adoption intentions among HIV-negative men who have sex with men (MSM) in romantic relationships.

    Science.gov (United States)

    Gamarel, Kristi E; Golub, Sarit A

    2015-04-01

    In the USA, men who have sex with men (MSM) in primary partnerships are at elevated risk for human immunodeficiency virus (HIV) infection. Pre-exposure prophylaxis (PrEP), a new biomedical prevention strategy, has potential to reduce HIV transmission. This study examined predictors of PrEP adoption intentions among HIV-negative MSM in primary partnerships. The sample included HIV-negative MSM (n = 164) who participated in an ongoing cross-sectional study with an in-person interview examining PrEP adoption intentions. Higher HIV risk perception, intimacy motivations for condomless sex, recent condomless anal sex with outside partners, education, and age were each independently associated with PrEP adoption intentions. In a multivariate model, only age, education, and intimacy motivations for condomless sex were significantly associated with PrEP adoption intentions. Intimacy motivations may play a central role in PrEP adoption for MSM couples. Incorporating relationship dynamics into biomedical strategies is a promising avenue for research and intervention.

  16. History Scene Investigations: From Clues to Conclusions

    Science.gov (United States)

    McIntyre, Beverly

    2011-01-01

    In this article, the author introduces a social studies lesson that allows students to learn history and practice reading skills, critical thinking, and writing. The activity is called History Scene Investigation or HSI, which derives its name from the popular television series based on crime scene investigations (CSI). HSI uses discovery learning…

  17. The visual light field in real scenes

    NARCIS (Netherlands)

    Xia, L.; Pont, S.C.; Heynderickx, I.E.J.R.

    2014-01-01

    Human observers’ ability to infer the light field in empty space is known as the “visual light field.” While most relevant studies were performed using images on computer screens, we investigate the visual light field in a real scene by using a novel experimental setup. A “probe” and a scene were

  18. Seroepidemiology of high-risk HPV in HIV-negative and HIV-infected MSM: the H2M study

    NARCIS (Netherlands)

    Mooij, Sofie H.; van der Klis, Fiona R. M.; van der Sande, Marianne A. B.; Schepp, Rutger M.; Speksnijder, Arjen G. C. L.; Bogaards, Johannes A.; de Melker, Hester E.; de Vries, Henry J. C.; Snijders, Peter J. F.; van der Loeff, Maarten F. Schim

    2013-01-01

    Men who have sex with men (MSM), in particular HIV-infected MSM, are at increased risk for diseases related to human papilloma virus (HPV). Our goal was to assess the effect of HIV status on the presence of type-specific antibodies against seven high-risk HPV types in HPV-unvaccinated MSM. Moreover,

  19. High HIV incidence among MSM prescribed postexposure prophylaxis, 2000-2009: indications for ongoing sexual risk behaviour

    NARCIS (Netherlands)

    Heuker, José; Sonder, Gerard J. B.; Stolte, Ineke; Geskus, Ronald; van den Hoek, Anneke

    2012-01-01

    Objective: To determine (trends in) HIV incidence among MSM who have recently had postexposure prophylaxis (PEP) prescribed in Amsterdam, compared with MSM participating in the Amsterdam Cohort Studies (ACS). Design and methods: We used data from MSM who were prescribed PEP in Amsterdam between 2000

  20. Anal and penile high-risk human papillomavirus prevalence in HIV-negative and HIV-infected MSM

    NARCIS (Netherlands)

    van Aar, Fleur; Mooij, Sofie H.; van der Sande, Marianne A. B.; Speksnijder, Arjen G. C. L.; Stolte, Ineke G.; Meijer, Chris J. L. M.; Verhagen, Dominique W. M.; King, Audrey J.; de Vries, Henry J. C.; Schim van der Loeff, Maarten F.

    2013-01-01

    Anal and penile high-risk human papillomavirus (HPV) infection is associated with anogenital cancer, which is especially common in HIV-infected MSM. We assessed HPV prevalence and determinants in MSM. Analysis of baseline data from a prospective cohort study. MSM aged 18 years or older were

  1. Emergence in Japan of an HIV-1 variant associated with transmission among men who have sex with men (MSM) in China: first indication of the International Dissemination of the Chinese MSM lineage.

    Science.gov (United States)

    Kondo, Makiko; Lemey, Philippe; Sano, Takako; Itoda, Ichiro; Yoshimura, Yukihiro; Sagara, Hiroko; Tachikawa, Natsuo; Yamanaka, Ko; Iwamuro, Shinya; Matano, Tetsuro; Imai, Mitsunobu; Kato, Shingo; Takebe, Yutaka

    2013-05-01

    A survey of HIV-1 strains circulating in the Tokyo-Kanagawa metropolitan area of Japan during 2004 to 2011 (n = 477) identified six Japanese males (patients 1 to 6), who harbored viruses with genome segments derived from a distinct CRF01_AE variant uniquely found among men who have sex with men (MSM) in China (designated CN.MSM.01-1). These six HIV infections were diagnosed in 2010 and 2011 among MSM (3 of 75) and men with unknown risk factors (3 of 63) and differed from the vast majority of HIV infections among MSM in Japan, which are overwhelmingly characterized by subtype B (239 of 246 [97.2%]). Approximately one-third (91 of 239 [38.1%]) of subtype B strains from MSM in Japan belong to a large monophyletic cluster (designated JP.MSM.B-1). In addition, we identified a smaller subtype B cluster (n = 8) (designated JP.MSM.B-2) that also contains strains from two Chinese MSM living in Japan. Interestingly, patients 5 and 6 were found to be coinfected with CRF01_AE (CN.MSM.01-1) and subtype B (JP.MSM.B-2 or JP.MSM.B-1) variants that are unique to the HIV-1 epidemics among MSM in China and Japan, respectively. Our study demonstrates for the first time the effect of the expanding HIV epidemic among MSM in China on transmission in neighboring countries and shows the ongoing mixing of CRF01_AE and subtype B lineages unique to HIV-1 that cocirculate in MSM populations in East Asia. This finding highlights the importance of strengthening epidemiological surveillance in the region and the need for effective measures to limit transmission among MSM in East Asia.

  2. Emergence in Japan of an HIV-1 Variant Associated with Transmission among Men Who Have Sex with Men (MSM) in China: First Indication of the International Dissemination of the Chinese MSM Lineage

    Science.gov (United States)

    Kondo, Makiko; Lemey, Philippe; Sano, Takako; Itoda, Ichiro; Yoshimura, Yukihiro; Sagara, Hiroko; Tachikawa, Natsuo; Yamanaka, Ko; Iwamuro, Shinya; Matano, Tetsuro; Imai, Mitsunobu; Kato, Shingo

    2013-01-01

    A survey of HIV-1 strains circulating in the Tokyo-Kanagawa metropolitan area of Japan during 2004 to 2011 (n = 477) identified six Japanese males (patients 1 to 6), who harbored viruses with genome segments derived from a distinct CRF01_AE variant uniquely found among men who have sex with men (MSM) in China (designated CN.MSM.01-1). These six HIV infections were diagnosed in 2010 and 2011 among MSM (3 of 75) and men with unknown risk factors (3 of 63) and differed from the vast majority of HIV infections among MSM in Japan, which are overwhelmingly characterized by subtype B (239 of 246 [97.2%]). Approximately one-third (91 of 239 [38.1%]) of subtype B strains from MSM in Japan belong to a large monophyletic cluster (designated JP.MSM.B-1). In addition, we identified a smaller subtype B cluster (n = 8) (designated JP.MSM.B-2) that also contains strains from two Chinese MSM living in Japan. Interestingly, patients 5 and 6 were found to be coinfected with CRF01_AE (CN.MSM.01-1) and subtype B (JP.MSM.B-2 or JP.MSM.B-1) variants that are unique to the HIV-1 epidemics among MSM in China and Japan, respectively. Our study demonstrates for the first time the effect of the expanding HIV epidemic among MSM in China on transmission in neighboring countries and shows the ongoing mixing of CRF01_AE and subtype B lineages unique to HIV-1 that cocirculate in MSM populations in East Asia. This finding highlights the importance of strengthening epidemiological surveillance in the region and the need for effective measures to limit transmission among MSM in East Asia. PMID:23365432

  3. Audio scene segmentation for video with generic content

    Science.gov (United States)

    Niu, Feng; Goela, Naveen; Divakaran, Ajay; Abdel-Mottaleb, Mohamed

    2008-01-01

    In this paper, we present a content-adaptive audio texture based method to segment video into audio scenes. The audio scene is modeled as a semantically consistent chunk of audio data. Our algorithm is based on "semantic audio texture analysis." At first, we train GMM models for basic audio classes such as speech, music, etc. Then we define the semantic audio texture based on those classes. We study and present two types of scene changes, those corresponding to an overall audio texture change and those corresponding to a special "transition marker" used by the content creator, such as a short stretch of music in a sitcom or silence in dramatic content. Unlike prior work using genre specific heuristics, such as some methods presented for detecting commercials, we adaptively find out if such special transition markers are being used and if so, which of the base classes are being used as markers without any prior knowledge about the content. Our experimental results show that our proposed audio scene segmentation works well across a wide variety of broadcast content genres.

  4. Una implementación computacional de un modelo de atención visual Bottom-up aplicado a escenas naturales/A Computational Implementation of a Bottom-up Visual Attention Model Applied to Natural Scenes

    Directory of Open Access Journals (Sweden)

    Juan F. Ramírez Villegas

    2011-12-01

    Full Text Available El modelo de atención visual bottom-up propuesto por Itti et al., 2000 [1], ha sido un modelo popular en tanto exhibe cierta evidencia neurobiológica de la visión en primates. Este trabajo complementa el modelo computacional de este fenómeno desde la dinámica realista de una red neuronal. Asimismo, esta aproximación se basa en la existencia de mapas topográficos que representan la prominencia de los objetos del campo visual para la formación de una representación general (mapa de prominencia, esta representación es la entrada de una red neuronal dinámica con interacciones locales y globales de colaboración y competencia que convergen sobre las principales particularidades (objetos de la escena.The bottom-up visual attention model proposed by Itti et al. 2000 [1], has been a popular model since it exhibits certain neurobiological evidence of primates’ vision. This work complements the computational model of this phenomenon using a neural network with realistic dynamics. This approximation is based on several topographical maps representing the objects saliency that construct a general representation (saliency map, which is the input for a dynamic neural network, whose local and global collaborative and competitive interactions converge to the main particularities (objects presented by the visual scene as well.

  5. Real-time scene generator

    Science.gov (United States)

    Lord, Eric; Shand, David J.; Cantle, Allan J.

    1996-05-01

    This paper describes the techniques which have been developed for an infra-red (IR) target, countermeasure and background image generation system working in real time for HWIL and Trial Proving applications. Operation is in the 3 to 5 and 8 to 14 micron bands. The system may be used to drive a scene projector (otherwise known as a thermal picture synthesizer) or for direct injection into equipment under test. The provision of realistic IR target and countermeasure trajectories and signatures, within representative backgrounds, enables the full performance envelope of a missile system to be evaluated. It also enables an operational weapon system to be proven in a trials environment without compromising safety. The most significant technique developed has been that of line by line synthesis. This minimizes the processing delays to the equivalent of 1.5 frames from input of target and sightline positions to the completion of an output image scan. Using this technique a scene generator has been produced for full closed loop HWIL performance analysis for the development of an air to air missile system. Performance of the synthesis system is as follows: 256 * 256 pixels per frame; 350 target polygons per frame; 100 Hz frame rate; and Gouraud shading, simple reflections, variable geometry targets and atmospheric scaling. A system using a similar technique has also bee used for direct insertion into the video path of a ground to air weapon system in live firing trials. This has provided realistic targets without degrading the closed loop performance. Delay of the modified video signal has been kept to less than 5 lines. The technique has been developed using a combination of 4 high speed Intel i860 RISC processors in parallel with the 4000 series XILINX field programmable gate arrays (FPGA). Start and end conditions for each line of target pixels are prepared and ordered in the I860. The merging with background pixels and output shading and scaling is then carried out in

  6. Antiretroviral therapy and reasons for not taking it among men having sex with men (MSM--results from the European MSM Internet Survey (EMIS.

    Directory of Open Access Journals (Sweden)

    Ulrich Marcus

    Full Text Available The preventive effects of antiretroviral treatment (ART on onward transmission of HIV are a major reason for broadening eligibility for ART. In the WHO European Region, surveillance reveals substantial differences in access to ART across regions and sub-populations. We analysed self-reported data on ART and reasons for not taking ART from EMIS, a large Pan-European Internet survey among men-who-have-sex-with-men (MSM.Respondents from 38 European countries reported their last HIV test result and, if diagnosed with HIV, their treatment status, and reasons for not taking or having stopped ART from a 7 item multiple choice list and/ or answered an open-ended question to give other reasons. Responses were classified as fear of consequences, perceived lack of need, and ART inaccessibility based on factor analysis. Associations between not taking ART because of fear of consequences, and demographic, behavioural and contextual indicators were identified in a multivariable regression model.13,353 (7.7% of 174,209 respondents had been diagnosed with HIV. Among them 3,391 (25.4% had never received ART, and 278 (2.1% had stopped taking ART. Perceived lack of need was by far the most common reason for not taking or stopping ART (mentioned by 3259 (88.8% respondents, followed by fear of consequences (428 (11.7%, and ART inaccessibility (86 (2.3%. For all reasons, an East-West gradient could be seen, with larger proportions of men living in Central and Eastern Europe reporting reasons other than medical advice for not taking ART. A minority of men were reluctant to start ART independent of medical advice and this was associated with experiences of discrimination in health care systems.ART is widely available for MSM diagnosed with HIV across Europe. Not being on treatment is predominantly due to treatment not being recommended by their physician and/or not perceived to be needed by the respondent.

  7. Antiretroviral Therapy and Reasons for Not Taking It among Men Having Sex with Men (MSM)—Results from the European MSM Internet Survey (EMIS)

    Science.gov (United States)

    Marcus, Ulrich; Hickson, Ford; Weatherburn, Peter; Furegato, Martina; Breveglieri, Michele; Berg, Rigmor C.; Schmidt, Axel J.

    2015-01-01

    Background The preventive effects of antiretroviral treatment (ART) on onward transmission of HIV are a major reason for broadening eligibility for ART. In the WHO European Region, surveillance reveals substantial differences in access to ART across regions and sub-populations. We analysed self-reported data on ART and reasons for not taking ART from EMIS, a large Pan-European Internet survey among men-who-have-sex-with-men (MSM). Methods Respondents from 38 European countries reported their last HIV test result and, if diagnosed with HIV, their treatment status, and reasons for not taking or having stopped ART from a 7 item multiple choice list and/ or answered an open-ended question to give other reasons. Responses were classified as fear of consequences, perceived lack of need, and ART inaccessibility based on factor analysis. Associations between not taking ART because of fear of consequences, and demographic, behavioural and contextual indicators were identified in a multivariable regression model. Results 13,353 (7.7%) of 174,209 respondents had been diagnosed with HIV. Among them 3,391 (25.4%) had never received ART, and 278 (2.1%) had stopped taking ART. Perceived lack of need was by far the most common reason for not taking or stopping ART (mentioned by 3259 (88.8%) respondents), followed by fear of consequences (428 (11.7%)), and ART inaccessibility (86 (2.3%)). For all reasons, an East-West gradient could be seen, with larger proportions of men living in Central and Eastern Europe reporting reasons other than medical advice for not taking ART. A minority of men were reluctant to start ART independent of medical advice and this was associated with experiences of discrimination in health care systems. Conclusions ART is widely available for MSM diagnosed with HIV across Europe. Not being on treatment is predominantly due to treatment not being recommended by their physician and/or not perceived to be needed by the respondent. PMID:25793882

  8. Multimodal computational attention for scene understanding and robotics

    CERN Document Server

    Schauerte, Boris

    2016-01-01

    This book presents state-of-the-art computational attention models that have been successfully tested in diverse application areas and can build the foundation for artificial systems to efficiently explore, analyze, and understand natural scenes. It gives a comprehensive overview of the most recent computational attention models for processing visual and acoustic input. It covers the biological background of visual and auditory attention, as well as bottom-up and top-down attentional mechanisms and discusses various applications. In the first part new approaches for bottom-up visual and acoustic saliency models are presented and applied to the task of audio-visual scene exploration of a robot. In the second part the influence of top-down cues for attention modeling is investigated. .

  9. Is the HIV epidemic stable among MSM in Mexico? HIV prevalence and risk behavior results from a nationally representative survey among men who have sex with men.

    Directory of Open Access Journals (Sweden)

    Sergio Bautista-Arredondo

    Full Text Available BACKGROUND: Recent evidence points to the apparent increase of HIV prevalence among men who have sex with men (MSM in different settings with concentrated epidemics, including the Latin American region. In 2011, Mexico implemented an ambitious HIV prevention program in all major cities, funded by the Global Fund to Fight Aids, Tuberculosis and Malaria. The program was intended to strengthen the prevention response for the most at risk populations: MSM and injecting drug users. This paper presents the HIV prevalence results of a nationally representative baseline survey in 24 Mexican cities throughout the 5 regions in the country and reports the socio-demographic and sexual risk behaviors that predict the probability of infection. METHODS: The survey was implemented in two phases. We first identified and characterized places where MSM gather in each city and then conducted in a second phase, a seroprevalence survey that included rapid HIV testing and a self-administered questionnaire. The prevalence of HIV was estimated by adjusting for positive predicted value. We applied a probit model to estimate the probability of having a positive result from the HIV test as a function of socio-demographic characteristics and self-reported sexual risk behaviors. RESULTS: We found an overall HIV prevalence among MSM gathering in meeting points of 16.9% [95% CI: 15.6-18.3], significantly higher than previously reported estimates. Our regression results suggest that the risk of infection increases with age, with the number of sexual partners, and among those who play a receptive sexual role, and the risk decreases with higher education. DISCUSSION: Our findings suggest a higher HIV prevalence among MSM than previously acknowledged and that a significant regional variability exist throughout the country. These two findings combined, signal an important dynamic in the epidemic that should be better understood and promptly addressed with strong prevention efforts

  10. Intimate Partner Violence, Minority Stress, and Sexual Risk-Taking Among US MSM.

    Science.gov (United States)

    Finneran, Catherine; Stephenson, Rob

    2013-11-18

    Abstract This paper examines the prevalence of intimate partner violence (IPV) among a national sample of internet-recruited U.S. MSM (n = 1,575), and examines associations between reporting of IPV, minority stress, and sexual risk-taking. Five outcomes are examined: experiences of physical and sexual violence, perpetration of physical and sexual violence, and unprotected anal intercourse (UAI) at last sexual encounter. MSM who reported experiencing more homophobic discrimination and internalized homophobia were more likely to report experiences of IPV. The results point to the need for prevention messages to address the external and internal stressors that influence both violence and sexual risk among MSM.

  11. Physical and Psychological Abuse among Seropositive African American MSM 50 Aged Years and Older.

    Science.gov (United States)

    Coleman, Christopher Lance

    2018-01-01

    Little is known about abuse experienced among African American men who have sex with men (MSM) who are 50 years and older. A series of focus groups were conducted to examine perspectives of seropositive African American MSM age 50 years and older who reported experiencing some form of psychological or physical abuse. Thirty African American MSM were divided into four focus groups and four themes emerged: "Fear Being Gay," "No One Else to Love Me," "Nowhere to Turn," and "Sexual Risk & Control." The data suggest there is a need to develop culturally tailored interventions for this population.

  12. The Influence of Content Meaningfulness on Eye Movements across Tasks: Evidence from Scene Viewing and Reading

    Directory of Open Access Journals (Sweden)

    Steven G Luke

    2016-03-01

    Full Text Available The present study investigated the influence of content meaningfulness on eye-movement control in reading and scene viewing. Texts and scenes were manipulated to make them uninterpretable, and then eye-movements in reading and scene-viewing were compared to those in pseudo-reading and pseudo-scene viewing. Fixation durations and saccade amplitudes were greater for pseudo-stimuli. The effect of the removal of meaning was seen exclusively in the tail of the fixation duration distribution in both tasks, and the size of this effect was the same across tasks. These findings suggest that eye movements are controlled by a common mechanism in reading and scene viewing. They also indicate that not all eye movements are responsive to the meaningfulness of stimulus content. Implications for models of eye movement control are discussed.

  13. Scenes of the self, and trance

    Directory of Open Access Journals (Sweden)

    Jan M. Broekman

    2014-02-01

    Full Text Available Trance shows the Self as a process involved in all sorts and forms of life. A Western perspective on a self and its reifying tendencies is only one (or one series of those variations. The process character of the self does not allow any coherent theory but shows, in particular when confronted with trance, its variability in all regards. What is more: the Self is always first on the scene of itself―a situation in which it becomes a sign for itself. That particular semiotic feature is again not a unified one but leads, as the Self in view of itself does, to series of scenes with changing colors, circumstances and environments. Our first scene “Beyond Monotheism” shows semiotic importance in that a self as determining component of a trance-phenomenon must abolish its own referent and seems not able to answer the question, what makes trance a trance. The Pizzica is an example here. Other social features of trance appear in the second scene, US post traumatic psychological treatments included. Our third scene underlines structures of an unfolding self: beginning with ‘split-ego’ conclusions, a self’s engenderment appears dependent on linguistic events and on spoken words in the first place. A fourth scene explores that theme and explains modern forms of an ego ―in particular those inherent to ‘citizenship’ or a ‘corporation’. The legal consequences are concentrated in the fifth scene, which considers a legal subject by revealing its ‘standing’. Our sixth and final scene pertains to the relation between trance and commerce. All scenes tie together and show parallels between Pizzica, rights-based behavior, RAVE music versus disco, commerce and trance; they demonstrate the meaning of trance as a multifaceted social phenomenon.

  14. Scene analysis in the natural environment

    DEFF Research Database (Denmark)

    Lewicki, Michael S; Olshausen, Bruno A; Surlykke, Annemarie

    2014-01-01

    that hinder further progress. Here we take the view that scene analysis is a universal problem solved by all animals, and that we can gain new insight by studying the problems that animals face in complex natural environments. In particular, the jumping spider, songbird, echolocating bat, and electric fish......, all exhibit behaviors that require robust solutions to scene analysis problems encountered in the natural environment. By examining the behaviors of these seemingly disparate animals, we emerge with a framework for studying scene analysis comprising four essential properties: (1) the ability to solve...

  15. Anomaly detection and localization in crowded scenes.

    Science.gov (United States)

    Li, Weixin; Mahadevan, Vijay; Vasconcelos, Nuno

    2014-01-01

    The detection and localization of anomalous behaviors in crowded scenes is considered, and a joint detector of temporal and spatial anomalies is proposed. The proposed detector is based on a video representation that accounts for both appearance and dynamics, using a set of mixture of dynamic textures models. These models are used to implement 1) a center-surround discriminant saliency detector that produces spatial saliency scores, and 2) a model of normal behavior that is learned from training data and produces temporal saliency scores. Spatial and temporal anomaly maps are then defined at multiple spatial scales, by considering the scores of these operators at progressively larger regions of support. The multiscale scores act as potentials of a conditional random field that guarantees global consistency of the anomaly judgments. A data set of densely crowded pedestrian walkways is introduced and used to evaluate the proposed anomaly detector. Experiments on this and other data sets show that the latter achieves state-of-the-art anomaly detection results.

  16. UPSCALING OF SOLAR INDUCED CHLOROPHYLL FLUORESCENCE FROM LEAF TO CANOPY USING THE DART MODEL AND A REALISTIC 3D FOREST SCENE

    Directory of Open Access Journals (Sweden)

    W. Liu

    2017-10-01

    Full Text Available Solar induced chlorophyll a fluorescence (SIF has been shown to be an excellent proxy of photosynthesis at multiple scales. However, the mechanical linkages between fluorescence and photosynthesis at the leaf level cannot be directly applied at canopy or field scales, as the larger scale SIF emission depends on canopy structure. This is especially true for the forest canopies characterized by high horizontal and vertical heterogeneity. While most of the current studies on SIF radiative transfer in plant canopies are based on the assumption of a homogeneous canopy, recently codes have been developed capable of simulation of fluorescence signal in explicit 3-D forest canopies. Here we present a canopy SIF upscaling method consisting of the integration of the 3-D radiative transfer model DART and a 3-D object model BLENDER. Our aim was to better understand the effect of boreal forest canopy structure on SIF for a spatially explicit forest canopy.

  17. Upscaling of Solar Induced Chlorophyll Fluorescence from Leaf to Canopy Using the Dart Model and a Realistic 3d Forest Scene

    Science.gov (United States)

    Liu, W.; Atherton, J.; Mõttus, M.; MacArthur, A.; Teemu, H.; Maseyk, K.; Robinson, I.; Honkavaara, E.; Porcar-Castell, A.

    2017-10-01

    Solar induced chlorophyll a fluorescence (SIF) has been shown to be an excellent proxy of photosynthesis at multiple scales. However, the mechanical linkages between fluorescence and photosynthesis at the leaf level cannot be directly applied at canopy or field scales, as the larger scale SIF emission depends on canopy structure. This is especially true for the forest canopies characterized by high horizontal and vertical heterogeneity. While most of the current studies on SIF radiative transfer in plant canopies are based on the assumption of a homogeneous canopy, recently codes have been developed capable of simulation of fluorescence signal in explicit 3-D forest canopies. Here we present a canopy SIF upscaling method consisting of the integration of the 3-D radiative transfer model DART and a 3-D object model BLENDER. Our aim was to better understand the effect of boreal forest canopy structure on SIF for a spatially explicit forest canopy.

  18. Risk factors for HIV infection in males who have sex with males (MSM) in Bangladesh.

    Science.gov (United States)

    Chan, Philip A; Khan, Omar A

    2007-07-12

    Recent surveillance data from Bangladesh indicate rising HIV infection among intravenous drug users (IDU) in the country. We suggest a likely association between HIV risk factors in this group and other groups, such as males who have sex with males (MSM). Data on MSM in Bangladesh was collected and analyzed from numerous primary and secondary sources, including government ministries, non-profit health organizations, and personal communications. The overall prevalence of HIV in Bangladesh is relatively low, but surveillance data indicate that infection has reached significant proportions in certain high-risk groups and may soon spread to other groups, specifically MSM. The epidemiology of HIV infection in other countries suggests that increasing rates of HIV in higher-risk populations can precede an epidemic in the general population. We review the data concerning MSM, IDU and HIV in Bangladesh from a variety of sources and propose ways to prevent HIV transmission.

  19. Top2btm symposium on health care for men who have sex with men (MSM

    Directory of Open Access Journals (Sweden)

    K Rebe

    2011-09-01

    Full Text Available Men who have sex with men (MSM are at high risk of HIV acquisition and transmission, and country-specific HIV prevalence rates are always higher in MSM than among heterosexual men. South African data confirm this, with reported HIV prevalences of 10.4 - 33.9% across various studies. Donors and government health planners have recognised the need for targeted programmes that address the high burden of HIV transmission and disease in stigmatised populations such as MSM, as well as other ‘most at risk populations’ (MARPS such as commercial sex workers, drug users and displaced refugees. Specific programmes targeting MSM and other MARPS have been included in the South African government’s current National Strategic Plan for health care and will feature in the new plan under development.

  20. Hepatitis A outbreak among MSM linked to casual sex and gay saunas in Copenhagen, Denmark

    DEFF Research Database (Denmark)

    Mazick, A; Howitz, Michael Frantz; Rex, S

    2005-01-01

    .2-26.9). Eleven of 18 cases and 14/62 controls had sex in gay saunas (ORMH 4.2, 95% CI 1.5-11.5). Sex at private homes appeared to be protective (ORMH 0.2, 95% CI 0.1-0.7). Casual sex including sex in gay saunas was an important risk factor for the spread of HAV among MSM in Copenhagen. The results......During an outbreak of hepatitis A predominantly among men who have sex with men (MSM) in Copenhagen, Denmark, in 2004, we did a case-control study to determine risk factors for infection. A case was an MSM >17 years, living in Copenhagen, with IgM positive hepatitis A infection diagnosed between...... with frequent partner change. To stop spread of hepatitis A among MSM in Europe, a European consensus on prevention and control measures may be required....

  1. Risk factors for HIV infection in Males who have Sex with Males (MSM in Bangladesh

    Directory of Open Access Journals (Sweden)

    Khan Omar A

    2007-07-01

    Full Text Available Abstract Background Recent surveillance data from Bangladesh indicate rising HIV infection among intravenous drug users (IDU in the country. We suggest a likely association between HIV risk factors in this group and other groups, such as males who have sex with males (MSM. Methods Data on MSM in Bangladesh was collected and analyzed from numerous primary and secondary sources, including government ministries, non-profit health organizations, and personal communications. Results The overall prevalence of HIV in Bangladesh is relatively low, but surveillance data indicate that infection has reached significant proportions in certain high-risk groups and may soon spread to other groups, specifically MSM. Conclusion The epidemiology of HIV infection in other countries suggests that increasing rates of HIV in higher-risk populations can precede an epidemic in the general population. We review the data concerning MSM, IDU and HIV in Bangladesh from a variety of sources and propose ways to prevent HIV transmission.

  2. Comparison of Two Team Learning and Team Entrepreneurship Models at a Finnish University of Applied Sciences. Setting the Scene for Future Development

    Directory of Open Access Journals (Sweden)

    Pasi Juvonen

    2017-02-01

    Full Text Available This team learning and team entre-preneurship model of education has been deployed at the Bachelor’s level in the degree programmes of IT and Business Administration (BA. In BA studies the students who take part in team learning have specialized in marketing since 2009 at the Saimaa University of Applied Sciences (SUAS. The model called ICT entrepreneurship study path (ICT-ESP has been developed for IT education. The ICT-ESP has been built on the theory of experien-tal learning and theories of knowledge creation and knowledge management. The students study and complete their degree as team entrepreneurs. The model has been further developed in the Business Administration Degree Programme with students who specialize in marketing. The Degree Programme in IT at the Bachelor’s level was terminated in 2011 by Finnish Min-istry of Education and Culture. Cur-rently, there are severe discussions on bringing it back – not as an IT but as an ICT Degree Programme. This article makes a cross-section of what has already been explored with the team learning and team entrepreneurship model and what the next steps will be. It makes a comparison of two originally sep-arately developed models and dis-cusses their best practices. The arti-cle also argues whether the upcom-ing ICT education should be orga-nized in a conventional way – as curriculum of courses, or as expan-sion of the current team learning and team entrepreneurship model. The data consists of field notes, meeting memos, and dozens of un-official discussions with colleagues and company representatives. Liter-ature studies made during the ongo-ing research, development, and in-novation (RDI projects offered an extra view of how the business con-text is changing and what should be done to make benefit out of the change. The results suggest that the up-coming ICT Degree Programme at SUAS should be integrated into the existing deployment of team learning and team entrepreneurship learning

  3. Three interactive scenes of The Crystal Cabinet

    OpenAIRE

    Unander-Scharin, Åsa

    2010-01-01

    The interactive scenes of The Crystal Cabinet (2008) constitute the first part in my choreographic research project exploring volatile bodies and multistable corporealities. This performance took the form of a dream play opera in twelve scenes including texts and images from William Blake’s (1757-1827) illuminated books. To create his books Blake invented a printing-machine with which he could print his handwritten poems and images. We transformed this idea into an interactive stage area wher...

  4. Unsupervised Moving Target Detection in Dynamic Scenes

    Science.gov (United States)

    2008-12-01

    training the algorithm to learn the background parameters. The need to train such algorithms for each scene separately limits their ability to be...deployed for automatic surveillance tasks, where manual re- training of the module to operate in each new scene is not feasible. A further shortcoming in...and (b). The camera panning is such that the objects of interest, viz. the two cyclists , undergo very small motion in the image coordinates. Figure 1

  5. Risk factors for HIV infection in Males who have Sex with Males (MSM) in Bangladesh

    OpenAIRE

    Chan, Philip A.; Khan, Omar A

    2007-01-01

    Background Recent surveillance data from Bangladesh indicate rising HIV infection among intravenous drug users (IDU) in the country. We suggest a likely association between HIV risk factors in this group and other groups, such as males who have sex with males (MSM). Methods Data on MSM in Bangladesh was collected and analyzed from numerous primary and secondary sources, including government ministries, non-profit health organizations, and personal communications. Results The overall prevalenc...

  6. Risk factors for HIV infection in Males who have Sex with Males (MSM) in Bangladesh

    OpenAIRE

    Khan Omar A; Chan Philip A

    2007-01-01

    Abstract Background Recent surveillance data from Bangladesh indicate rising HIV infection among intravenous drug users (IDU) in the country. We suggest a likely association between HIV risk factors in this group and other groups, such as males who have sex with males (MSM). Methods Data on MSM in Bangladesh was collected and analyzed from numerous primary and secondary sources, including government ministries, non-profit health organizations, and personal communications. Results The overall ...

  7. Scene change detection based on multimodal integration

    Science.gov (United States)

    Zhu, Yingying; Zhou, Dongru

    2003-09-01

    Scene change detection is an essential step to automatic and content-based video indexing, retrieval and browsing. In this paper, a robust scene change detection and classification approach is presented, which analyzes audio, visual and textual sources and accounts for their inter-relations and coincidence to semantically identify and classify video scenes. Audio analysis focuses on the segmentation of audio stream into four types of semantic data such as silence, speech, music and environmental sound. Further processing on speech segments aims at locating speaker changes. Video analysis partitions visual stream into shots. Text analysis can provide a supplemental source of clues for scene classification and indexing information. We integrate the video and audio analysis results to identify video scenes and use the text information detected by the video OCR technology or derived from transcripts available to refine scene classification. Results from single source segmentation are in some cases suboptimal. By combining visual, aural features adn the accessorial text information, the scence extraction accuracy is enhanced, and more semantic segmentations are developed. Experimental results are proven to rather promising.

  8. Prevalence of HIV among MSM in Europe: comparison of self-reported diagnoses from a large scale internet survey and existing national estimates.

    Science.gov (United States)

    Marcus, Ulrich; Hickson, Ford; Weatherburn, Peter; Schmidt, Axel J

    2012-11-14

    Country level comparisons of HIV prevalence among men having sex with men (MSM) is challenging for a variety of reasons, including differences in the definition and measurement of the denominator group, recruitment strategies and the HIV detection methods. To assess their comparability, self-reported data on HIV diagnoses in a 2010 pan-European MSM internet survey (EMIS) were compared with pre-existing estimates of HIV prevalence in MSM from a variety of European countries. The first pan-European survey of MSM recruited more than 180,000 men from 38 countries across Europe and included questions on the year and result of last HIV test. HIV prevalence as measured in EMIS was compared with national estimates of HIV prevalence based on studies using biological measurements or modelling approaches to explore the degree of agreement between different methods. Existing estimates were taken from Dublin Declaration Monitoring Reports or UNAIDS country fact sheets, and were verified by contacting the nominated contact points for HIV surveillance in EU/EEA countries. The EMIS self-reported measurements of HIV prevalence were strongly correlated with existing estimates based on biological measurement and modelling studies using surveillance data (R(2)=0.70 resp. 0.72). In most countries HIV positive MSM appeared disproportionately likely to participate in EMIS, and prevalences as measured in EMIS are approximately twice the estimates based on existing estimates. Comparison of diagnosed HIV prevalence as measured in EMIS with pre-existing estimates based on biological measurements using varied sampling frames (e.g. Respondent Driven Sampling, Time and Location Sampling) demonstrates a high correlation and suggests similar selection biases from both types of studies. For comparison with modelled estimates the self-selection bias of the Internet survey with increased participation of men diagnosed with HIV has to be taken into account. For most countries self-reported EMIS

  9. Prevalence of HIV among MSM in Europe: comparison of self-reported diagnoses from a large scale internet survey and existing national estimates

    Directory of Open Access Journals (Sweden)

    Marcus Ulrich

    2012-11-01

    Full Text Available Abstract Background Country level comparisons of HIV prevalence among men having sex with men (MSM is challenging for a variety of reasons, including differences in the definition and measurement of the denominator group, recruitment strategies and the HIV detection methods. To assess their comparability, self-reported data on HIV diagnoses in a 2010 pan-European MSM internet survey (EMIS were compared with pre-existing estimates of HIV prevalence in MSM from a variety of European countries. Methods The first pan-European survey of MSM recruited more than 180,000 men from 38 countries across Europe and included questions on the year and result of last HIV test. HIV prevalence as measured in EMIS was compared with national estimates of HIV prevalence based on studies using biological measurements or modelling approaches to explore the degree of agreement between different methods. Existing estimates were taken from Dublin Declaration Monitoring Reports or UNAIDS country fact sheets, and were verified by contacting the nominated contact points for HIV surveillance in EU/EEA countries. Results The EMIS self-reported measurements of HIV prevalence were strongly correlated with existing estimates based on biological measurement and modelling studies using surveillance data (R2=0.70 resp. 0.72. In most countries HIV positive MSM appeared disproportionately likely to participate in EMIS, and prevalences as measured in EMIS are approximately twice the estimates based on existing estimates. Conclusions Comparison of diagnosed HIV prevalence as measured in EMIS with pre-existing estimates based on biological measurements using varied sampling frames (e.g. Respondent Driven Sampling, Time and Location Sampling demonstrates a high correlation and suggests similar selection biases from both types of studies. For comparison with modelled estimates the self-selection bias of the Internet survey with increased participation of men diagnosed with HIV has to be

  10. Willingness of US men who have sex with men (MSM to participate in Couples HIV Voluntary Counseling and Testing (CVCT.

    Directory of Open Access Journals (Sweden)

    Bradley H Wagenaar

    Full Text Available We evaluated willingness to participate in CVCT and associated factors among MSM in the United States.5,980 MSM in the US, recruited through MySpace.com, completed an online survey March-April, 2009. A multivariable logistic regression model was built using being "willing" or "unwilling" to participate in CVCT in the next 12 months as the outcome.Overall, 81.5% of respondents expressed willingness to participate in CVCT in the next year. Factors positively associated with willingness were: being of non-Hispanic Black (adjusted odds ratio [aOR]: 1.5, 95% confidence interval [CI]: 1.2-1.8, Hispanic (aOR: 1.3, CI: 1.1-1.6, or other (aOR: 1.4, CI: 1.1-1.8 race/ethnicity compared to non-Hispanic White; being aged 18-24 (aOR: 2.5, CI: 1.7-3.8, 25-29 (aOR: 2.3, CI: 1.5-3.6, 30-34 (aOR: 1.9, CI: 1.2-3.1, and 35-45 (aOR: 2.3, CI: 1.4-3.7 years, all compared to those over 45 years of age; and having had a main male sex partner in the last 12 months (aOR: 1.9, CI: 1.6-2.2. Factors negatively associated with willingness were: not knowing most recent male sex partner's HIV status (aOR: 0.81, CI: 0.69-0.95 compared to knowing that the partner was HIV-negative; having had 4-7 (aOR: 0.75, CI: 0.61-0.92 or >7 male sex partners in the last 12 months (aOR: 0.62, CI: 0.50-0.78 compared to 1 partner; and never testing for HIV (aOR: 0.38, CI: 0.31-0.46, having been tested over 12 months ago (aOR: 0.63, CI: 0.50-0.79, or not knowing when last HIV tested (aOR: 0.67, CI: 0.51-0.89, all compared to having tested 0-6 months previously.Young MSM, men of color, and those with main sex partners expressed a high level of willingness to participate in couples HIV counseling and testing with a male partner in the next year. Given this willingness, it is likely feasible to scale up and evaluate CVCT interventions for US MSM.

  11. Genetic mapping of escalated aggression in wild-derived mouse strain MSM/Ms: association with serotonin-related genes

    Directory of Open Access Journals (Sweden)

    Aki eTakahashi

    2014-06-01

    Full Text Available The Japanese wild-derived mouse strain MSM/Ms (MSM retains a wide range of traits related to behavioral wildness, including high levels of emotionality and avoidance of humans. In this study, we observed that MSM showed a markedly higher level of aggression than the standard laboratory strain C57BL/6J. Whereas almost all MSM males showed high frequencies of attack bites and pursuit in the resident-intruder test, only a few C57BL/6J males showed aggressive behaviors, with these behaviors observed at only a low frequency. Sexually mature MSM males in their home cages killed their littermates, or sometimes female pair-mates. To study the genetic and neurobiological mechanisms that underlie the escalated aggression observed in MSM mice, we analyzed reciprocal F1 crosses and five consomic strains of MSM (Chr 4, 13, 15, X and Y against the background of C57BL/6J. We identified two chromosomes, Chr 4 and Chr 15, which were involved in the heightened aggression observed in MSM. These chromosomes had different effects on aggression: whereas MSM Chr 15 increased agitation and initiation of aggressive events, MSM Chr 4 induced a maladaptive level of aggressive behavior. Expression analysis of mRNAs of serotonin receptors, serotonin transporter and Tph2, an enzyme involved in serotonin synthesis in seven brain areas, indicated several differences among MSM, C57BL/6J, and their consomic strains. We found that Tph2 expression in the midbrain was increased in the Chr 4 consomic strain, as well as in MSM, and that there was a strong positive genetic correlation between aggressive behavior and Tph2 expression at the mRNA level. Therefore, it is possible that increased expression of the Tph2 gene is related to escalated aggression observed in MSM.

  12. Describing visual scenes: towards a neurolinguistics based on construction grammar.

    Science.gov (United States)

    Arbib, Michael A; Lee, Jinyong

    2008-08-15

    The present paper is part of a larger effort to locate the production and perception of language within the broader context of brain mechanisms for action and perception more generally. Here we model function in terms of the competition and cooperation of schemas. We use the task of describing visual scenes to explore the suitability of Construction Grammar as an appropriate framework for a schema-based linguistics. We recall the early VISIONS model of schema-based computer analysis of static visual scenes and then introduce SemRep as a graphical representation of dynamic visual scenes designed to support the generation of varied descriptions of episodes. We report preliminary results on implementing the production of sentences using Template Construction Grammar (TCG), a new form of construction grammar distinguished by its use of SemRep to express semantics. We summarize data on neural correlates relevant to future work on TCG within the context of neurolinguistics, and show how the relation between SemRep and TCG can serve as the basis for modeling language comprehension.

  13. Geographic Data Bases Supporting Scene Generation

    Science.gov (United States)

    Lukes, George E.

    1980-12-01

    Recent activity in synthetic reference scene generation from geographic data bases has lead to new and expanding production responsibilities for the mapping community. It has also spawned a new and growing population of geographic data base users. Optimum utilization of this data requires an understanding of the natural and cultural patterns represented as well as knowledge of the conventions and specifications which guide data base preparation. Prudence dictates effective mechanisms for data base inspection by the user. Appropriate implementation of data display procedures can provide this capability while also supporting routine analysis of data base content. This paper first illustrates a set of convenient mechanisms for the display of the elevation and planimetric components of geographic data files. Then, a new USAETL program in Computer-Assisted Photo Interpretation Research (CAPIR) is introduced. The CAPIR program will explore issues of direct data entry to create geographic data bases from stereo aerial photography. CAPIR also provides a technique for displaying geographic data base contents in corresponding three-dimensional photo models. This capability, termed superposition, will impact on the critical tasks of data validation, revision and intensification which are essential for effective management of geographic files.

  14. Representations and Techniques for 3D Object Recognition and Scene Interpretation

    CERN Document Server

    Hoiem, Derek

    2011-01-01

    One of the grand challenges of artificial intelligence is to enable computers to interpret 3D scenes and objects from imagery. This book organizes and introduces major concepts in 3D scene and object representation and inference from still images, with a focus on recent efforts to fuse models of geometry and perspective with statistical machine learning. The book is organized into three sections: (1) Interpretation of Physical Space; (2) Recognition of 3D Objects; and (3) Integrated 3D Scene Interpretation. The first discusses representations of spatial layout and techniques to interpret physi

  15. Assessing the feasibility of harm reduction services for MSM: the late night breakfast buffet study

    Directory of Open Access Journals (Sweden)

    Kellogg Timothy A

    2006-10-01

    Full Text Available Abstract Background Despite the leveling off in new HIV infections among men who have sex with men (MSM in San Francisco, new evidence suggests that many recent HIV infections are linked with the use of Methamphetamine (MA. Among anonymous HIV testers in San Francisco, HIV incidence among MA users was 6.3% compared to 2.1% among non-MA users. Of particular concern for prevention programs are frequent users and HIV positive men who use MA. These MSM pose a particular challenge to HIV prevention efforts due to the need to reach them during very late night hours. Methods The purpose of the Late Night Breakfast Buffet (LNBB was to determine the feasibility and uptake of harm reduction services by a late night population of MSM. The "buffet" of services included: needle exchange, harm reduction information, oral HIV testing, and urine based sexually transmitted infection (STI testing accompanied by counseling and consent procedures. The study had two components: harm reduction outreach and a behavioral survey. For 4 months during 2004, we provided van-based harm reduction services in three neighborhoods in San Francisco from 1 – 5 a.m. for anyone out late at night. We also administered a behavioral risk and service utilization survey among MSM. Results We exchanged 2000 needles in 233 needle exchange visits, distributed 4500 condoms/lubricants and provided 21 HIV tests and 12 STI tests. Fifty-five MSM enrolled in the study component. The study population of MSM was characterized by low levels of income and education whose ages ranged from 18 – 55. Seventy-eight percent used MA in the last 3 months; almost 25% used MA every day in the same time frame. Of the 65% who ever injected, 97% injected MA and 13% injected it several times a day. MA and alcohol were strong influences in the majority of unprotected sexual encounters among both HIV negative and HIV positive MSM. Conclusion We reached a disenfranchised population of MA-using MSM who are at

  16. Community engagement in sexual health and uptake of HIV testing and syphilis testing among MSM in China: a cross-sectional online survey.

    Science.gov (United States)

    Zhang, Tiange P; Liu, Chuncheng; Han, Larry; Tang, Weiming; Mao, Jessica; Wong, Terrence; Zhang, Ye; Tang, Songyuan; Yang, Bin; Wei, Chongyi; Tucker, Joseph D

    2017-04-03

    HIV and syphilis testing rates remain low among men who have sex with men (MSM) in low- and middle-income countries (LMICs). Community engagement has been increasingly used to promote HIV testing among key populations in high-income countries, often in settings with stronger civil society. This study aimed to assess socio-demographic, behavioural, and community engagement factors associated with HIV and syphilis testing among MSM in China. MSM ≥16 years old who had condomless sex in the past three months were recruited nationwide to complete a cross-sectional online survey in November 2015. Data were collected on socio-demographics, sexual behaviours, HIV testing, syphilis testing, and community engagement in sexual health. We defined community engagement in sexual health using six items assessing awareness and advocacy of sexual health programmes. The underlying factor structure of a 6-item community engagement scale was determined through exploratory factor analysis. Univariate and multivariable logistic regressions identified correlates of HIV and syphilis testing. 1189 MSM were recruited. 54% (647/1189) of men had ever tested for HIV and 30% (354/1189) had ever tested for syphilis. Factor analysis suggested three levels of community engagement (minimal, moderate, and substantial) and this model explained 79.5% of observed variance. A quarter (26%, 312/1189) reported none to minimal engagement, over one half (54%, 644/1189) reported moderate engagement, and a fifth (20%, 233/1189) reported substantial engagement. Multivariable logistic regression showed that MSM with greater community engagement in sexual health were more likely to have ever tested for HIV (substantial vs. no engagement: aOR 7.91, 95% CI 4.98-12.57) and for syphilis (substantial vs. no engagement: aOR 5.35, 95% CI 3.16-9.04). HIV and syphilis testing are suboptimal among MSM in China. Community engagement may be useful for promoting testing in China and should be considered in intervention

  17. Structural and environmental factors are associated with internalised homonegativity in men who have sex with men: findings from the European MSM Internet Survey (EMIS) in 38 countries.

    Science.gov (United States)

    Berg, Rigmor C; Ross, Michael W; Weatherburn, Peter; Schmidt, Axel J

    2013-02-01

    Internalised homonegativity refers to a gay person's negative feelings about homosexuality and is believed to stem from negative societal stereotypes and attitudes towards homosexuality. Surprisingly, little research has centred on this link. In this research, we aimed to examine the associations between internalised homonegativity and structural forces, cultural influence, and access to sexual health promotion measures among a sample of 144,177 men who have sex with men (MSM) in 38 European countries. Participants were recruited as part of the European MSM Internet Survey (EMIS) during 2010. It was a self-completion, multilingual Internet-based survey for men living in Europe who have sex with men and/or feel attracted to men. Assumed causal relations were tested through multiple regression models. Variables at the structure of rule-systems (macro-level) that were significantly and negatively associated with internalised homonegativity were the presence of laws recognising same-sex relationships and same-sex adoption. In the meso-level model, greater proportions of the population expressing that they would not like to have homosexuals as neighbours predicted higher internalised homonegativity. In the last model, five variables were significantly and negatively associated with internalised homonegativity: being exposed to HIV/STI information for MSM, access to HIV testing, access to STI testing, access to condoms, and experience of gay-related hostility. In turn, men who had tested for HIV in the past year evidenced lower internalised homonegativity. This is the largest and certainly most geographically diverse study to date to examine structural and environmental predictors of internalised homonegativity among MSM. Our results show that one insidious consequence of society's stigma towards homosexuals is the internalisation of that stigma by gay and bisexual men themselves, thus, drawing attention to the importance of promoting social equity for self

  18. Sociodemographic and sexual behavior characteristics of an online MSM sample in Guangdong, China.

    Science.gov (United States)

    Huang, L; Nehl, E J; Lin, L; Meng, G; Liu, Q; Ross, M W; Wong, F Y

    2014-01-01

    Public health research and interventions often assume that men who have sex with men (MSM) who use the Internet in China have similar characteristics to those in Western countries, though with little empirical evidence. This study aimed to describe and examine the sociodemographic and basic sexual behavioral characteristics of an online sample of MSM in Guangdong, China. In 2010, a total of 1100 MSM were recruited from an lesbian, gay, bisexual, and transgender (LGBT)-oriented website and were asked about their sociodemographic and sexual behavior characteristics. The majority of the participants (77.9%) self-identified as homosexual, and the mean age was 30.0 years (SD = 6.7). About 80% of the participants had attained a college degree and only 4.8% were unemployed. About 60% had a monthly salary of more than CNY 3000 (476 USD), and more than 10% were married. The majority (71.7%) had used condoms in the last anal sex. Nearly half of the participants have never been tested for HIV or other sexually transmitted infections (STIs) (47.3% and 47.7%, respectively). More than 80% were willing to be contacted by researchers after the survey. Findings indicate that the sociodemographic characteristics of Chinese MSM who use the Internet are relatively similar to those in the Western countries. However, Chinese MSM are less likely to self-identify as homosexual and be tested for HIV and other STIs than Western MSM. On a positive note, Chinese MSM would be likely to engage in e-technology research showing potential feasibility of an online HIV/STI intervention.

  19. Nonvolitional sex and HIV-related sexual risk behaviours among MSM in the United States.

    Science.gov (United States)

    Nasrullah, Muazzam; Oraka, Emeka; Chavez, Pollyanna R; Valverde, Eduardo; Dinenno, Elizabeth

    2015-08-24

    We estimated the prevalence of lifetime nonvolitional sex (NVS) among MSM by demographic characteristics, and characterized its association with HIV-related sexual risk behaviours among MSM in the United States. The National Survey of Family Growth (NSFG) is a nationally representative cross-sectional survey of the United States. NSFG data from recent cycles 2002, and 2006-2010 were weighted and analysed for men aged 18-44 years who reported ever having anal or oral intercourse with another male. Associations of lifetime NVS (forced sex by men or women) and age of first NVS experience (sexual risk behaviour outcomes in the past 12 months (i.e. sex with two or more male sex partners; exchanged sex for money or drugs; sex with IDU; sex with HIV-positive person; sex with two or more female sex partners) were assessed using adjusted prevalence ratios (aPR). An estimated 3 226 872 or 5.8% of men aged 18-44 years were identified as MSM with 24.6% of them reporting ever experiencing NVS. MSM reporting NVS at age 18 years or older were more likely to have had sex with an IDU [aPR = 4.40; 95% confidence interval (95% CI) 1.78-10.88] and exchanged sex for money or drugs (aPR = 2.52; 95% CI 1.17-5.43) in the past 12 months compared with those not reporting NVS. NVS for MSM less than 18 years of age was associated with exchanging sex for money or drugs. Effective interventions to raise awareness of NVS among MSM and to offer support for MSM who have experienced NVS are needed.

  20. A prospective study of anal cancer screening in HIV-positive and negative MSM.

    Science.gov (United States)

    Schofield, Alice M; Sadler, Laura; Nelson, Linsey; Gittins, Matthew; Desai, Mina; Sargent, Alex; McMahon, Raymond F T; Hill, James; Crosbie, Emma J; Patnick, Julietta; Kitchener, Henry C

    2016-06-01

    The study sought to establish the feasibility and acceptability of anal screening among men MSM. Prospective cohort study. Sexual health clinics in tertiary care. Known HIV-positive and negative MSM who have anoreceptive intercourse. Anal screening with human papilloma virus (HPV) testing, liquid-based cytology and high-resolution anoscopy with biopsy of anoscopic abnormalities. Participants completed questionnaires at baseline and at 6 months. Anal HPV was highly prevalent in MSM (HIV-positive, 88% and HIV-negative, 78%). Despite the high prevalence of cytological abnormality in both HIV-positive (46.2%) and negative (35.0%) MSM, almost half of anal intraepithelial neoplasia (AIN) of all grades were associated with negative cytology. Anoscopically directed biopsies detected AIN3 or worse (AIN3+) in 14 of 203 (6.9%) of HIV-positive MSM and three of 81 (3.7%) HIV-negative MSM. The corresponding prevalence of AIN2+ was 26.6 and 20.9%, respectively. One case of AIN3 was detected at the second visit. Screening was considered to be highly acceptable by participants. The high prevalence of high-risk-HPV and frequency of false negative cytology in this study suggest that high-resolution anoscopy would have most clinical utility, as a primary screening tool for anal cancer in a high-risk group. The prevalence of AIN3+ in HIV-positive MSM lends support for a policy of screening this group, but the high prevalence of lower grade lesions which do not warrant immediate treatment and the limitations of treating high-grade lesions requires careful consideration in terms of a screening policy.

  1. Determinants of never having tested for HIV among MSM in the Netherlands

    Science.gov (United States)

    den Daas, Chantal; Doppen, Martine; Schmidt, Axel J; Op de Coul, Eline

    2016-01-01

    Objectives Men who have sex with men (MSM) who are unaware of their HIV infection are more likely to infect others, and unable to receive treatment. Therefore, we aimed to identify the proportion and characteristics of Dutch MSM who never tested for HIV. Methods In 2010, the European MSM Internet Survey (EMIS) recruited 174 209 men from 38 countries through an anonymous online questionnaire in 25 languages. We analysed data from participants living in the Netherlands (N=3787). The outcome we investigated was having never (lifetime) been tested for HIV. Results A total of 770 MSM (20.4%) had never been tested for HIV. In multivariate regression analyses, not being from Amsterdam (adjusted OR, aOR 1.54, CI 1.17 to 2.03), with low education (aOR 1.28, CI 1.04 to 1.57) and low knowledge on HIV-testing (aOR 2.23, CI 1.37 to 3.64) were significantly associated with never having tested. Lower sexual risk (including having fewer sexual partners (aOR 2.19, CI 1.57 to 3.04) and no anal intercourse (aOR 5.99, CI 3.04 to 11.77)), and less social engagement (including being less out (aOR 1.93, CI 1.55 to 2.40)) were also associated with having never been tested. Additionally, 36.1% of MSM who never tested for HIV reported high-risk sexual behaviour that may have put them at HIV risk. Conclusions MSM make their own risk assessments that inform their choices about HIV-testing. Nevertheless, MSM who were never tested may have been at risk for HIV, and remain important to target for HIV interventions. PMID:26758261

  2. Maxwellian Eye Fixation during Natural Scene Perception

    Directory of Open Access Journals (Sweden)

    Jean Duchesne

    2012-01-01

    Full Text Available When we explore a visual scene, our eyes make saccades to jump rapidly from one area to another and fixate regions of interest to extract useful information. While the role of fixation eye movements in vision has been widely studied, their random nature has been a hitherto neglected issue. Here we conducted two experiments to examine the Maxwellian nature of eye movements during fixation. In Experiment 1, eight participants were asked to perform free viewing of natural scenes displayed on a computer screen while their eye movements were recorded. For each participant, the probability density function (PDF of eye movement amplitude during fixation obeyed the law established by Maxwell for describing molecule velocity in gas. Only the mean amplitude of eye movements varied with expertise, which was lower in experts than novice participants. In Experiment 2, two participants underwent fixed time, free viewing of natural scenes and of their scrambled version while their eye movements were recorded. Again, the PDF of eye movement amplitude during fixation obeyed Maxwell’s law for each participant and for each scene condition (normal or scrambled. The results suggest that eye fixation during natural scene perception describes a random motion regardless of top-down or of bottom-up processes.

  3. Moving through a multiplex holographic scene

    Science.gov (United States)

    Mrongovius, Martina

    2013-02-01

    This paper explores how movement can be used as a compositional element in installations of multiplex holograms. My holographic images are created from montages of hand-held video and photo-sequences. These spatially dynamic compositions are visually complex but anchored to landmarks and hints of the capturing process - such as the appearance of the photographer's shadow - to establish a sense of connection to the holographic scene. Moving around in front of the hologram, the viewer animates the holographic scene. A perception of motion then results from the viewer's bodily awareness of physical motion and the visual reading of dynamics within the scene or movement of perspective through a virtual suggestion of space. By linking and transforming the physical motion of the viewer with the visual animation, the viewer's bodily awareness - including proprioception, balance and orientation - play into the holographic composition. How multiplex holography can be a tool for exploring coupled, cross-referenced and transformed perceptions of movement is demonstrated with a number of holographic image installations. Through this process I expanded my creative composition practice to consider how dynamic and spatial scenes can be conveyed through the fragmented view of a multiplex hologram. This body of work was developed through an installation art practice and was the basis of my recently completed doctoral thesis: 'The Emergent Holographic Scene — compositions of movement and affect using multiplex holographic images'.

  4. Scene analysis in the natural environment

    Directory of Open Access Journals (Sweden)

    Michael S Lewicki

    2014-04-01

    Full Text Available The problem of scene analysis has been studied in a number of different fields over the past decades. These studies have led to a number of important insights into problems of scene analysis, but not all of these insights are widely appreciated. Despite this progress, there are also critical shortcomings in current approaches that hinder further progress. Here we take the view that scene analysis is a universal problem solved by all animals, and that we can gain new insight by studying the problems that animals face in complex natural environments. In particular, the jumping spider, songbird, echolocating bat, and electric fish, all exhibit behaviors that require robust solutions to scene analysis problems encountered in the natural environment. By examining the behaviors of these seemingly disparate animals, we emerge with a framework for studying analysis comprising four essential properties: 1 the ability to solve ill-posed problems, 2 the ability to integrate and store information across time and modality, 3 efficient recovery and representation of 3D scene structure, and 4 the use of optimal motor actions for acquiring information to progress towards behavioral goals.

  5. Estimating changes in lighting direction in binocularly viewed three-dimensional scenes

    Science.gov (United States)

    Gerhard, Holly E.; Maloney, Laurence T.

    2010-01-01

    We examine human ability to detect changes in scene lighting. Thirteen observers viewed three-dimensional rendered scenes stereoscopically. Each scene consisted of a randomly generated three-dimensional “Gaussian bump” surface rendered under a combination of collimated and diffuse light sources. During each trial, the collimated source underwent a small, quick change of position in one of four directions. The observer's task was to classify the direction of the lighting change. All observers were above chance in performing the task. We developed a model that combined two sources of information, a shape map and a shading map, to predict lighting change direction. We used this model to predict patterns of errors both across observers and across scenes differing in shape. We found that errors in estimating lighting direction were primarily the result of errors in representing surface shape. We characterized the surface features that affected performance in the classification task. PMID:21106676

  6. Diffraction analysis for digital micromirror device scene projectors in the long-wave infrared

    Science.gov (United States)

    Han, Qing; Wang, Jian; Zhang, Jianzhong; Sun, Qiang

    2016-08-01

    Diffraction effects play a significant role in scene projectors by digital micromirror devices (DMDs) in the long-wave infrared (IR) band (8 to 12 μm). The contrast provided by these projector systems can become noticeably worse because of the diffraction characteristics of the DMD. The actual diffraction characteristics of the DMD deviate significantly from the predictions of scalar diffraction theory in the long-wave IR. To address this issue, we built a vector diffraction-grating model of the DMD; the diffraction grating model is simulated with MATLAB. Furthermore, we analyze the effect of incident angle and polarization, which are the main factors that decrease the contrast of DMD-based scene projectors in the long-wave IR. Finally, an effective method to improve the contrast of the scene projector system is given, and the maximum contrast of the scene projector system is ˜0.7.

  7. HIV Testing Among Internet-Using MSM in the United States: Systematic Review.

    Science.gov (United States)

    Noble, Meredith; Jones, Amanda M; Bowles, Kristina; DiNenno, Elizabeth A; Tregear, Stephen J

    2017-02-01

    Regular HIV testing enables early identification and treatment of HIV among at-risk men who have sex with men (MSM). Characterizing HIV testing needs for Internet-using MSM informs development of Internet-facilitated testing interventions. In this systematic review we analyze HIV testing patterns among Internet-using MSM in the United States who report, through participation in an online study or survey, their HIV status as negative or unknown and identify demographic or behavioral risk factors associated with testing. We systematically searched multiple electronic databases for relevant English-language articles published between January 1, 2005 and December 16, 2014. Using meta-analysis, we summarized the proportion of Internet-using MSM who had ever tested for HIV and the proportion who tested in the 12 months preceding participation in the online study or survey. We also identified factors predictive of these outcomes using meta-regression and narrative synthesis. Thirty-two studies that enrolled 83,186 MSM met our inclusion criteria. Among the studies reporting data for each outcome, 85 % (95 % CI 82-87 %) of participants had ever tested, and 58 % (95 % CI 53-63 %) had tested in the year preceding enrollment in the study, among those for whom those data were reported. Age over 30 years, at least a college education, use of drugs, and self-identification as being homosexual or gay were associated with ever having tested for HIV. A large majority of Internet-using MSM indicated they had been tested for HIV at some point in the past. A smaller proportion-but still a majority-reported they had been tested within the year preceding study or survey participation. MSM who self-identify as heterosexual or bisexual, are younger, or who use drugs (including non-injection drugs) may be less likely to have ever tested for HIV. The overall findings of our systematic review are encouraging; however, a subpopulation of MSM may benefit from targeted outreach. These

  8. Impact of perceived HIV stigma within men who have sex with men community on mental health of seropositive MSM.

    Science.gov (United States)

    Chong, Eddie S K; Mak, Winnie W S; Tam, Terence C Y; Zhu, Chen; Chung, Rita W Y

    2017-01-01

    Emerging evidence has suggested that seropositive men who have sex with men (MSM) do not only face biased treatment from the general public but also from members of the MSM community. We conceptualized such biases perpetuated within the MSM community as human immunodeficiency virus (HIV) in-group stigma. This study examined the pathways by which perceived HIV in-group stigma impacted the mental health of seropositive MSM in Hong Kong. Internalized HIV stigma, serostatus disclosure concerns, and negative reactions towards HIV stigma were hypothesized as intermediate factors. Based on 100 Chinese seropositive MSM who were on antiretroviral therapy, results of a path analysis partially supported our hypotheses. Only negative reactions towards HIV stigma within the MSM community was a significant intermediate factor. The findings highlight the importance of understanding seropositive MSM's different reactions to HIV stigma perpetuated within the MSM community. On top of stigma reduction research, further research may explore ways that help seropositive MSM cope with HIV in-group stigma and foster resilience.

  9. EFSA Panel on Biological Hazards (BIOHAZ); Scientific Opinion on the public health risks related to mechanically separated meat (MSM) derived from poultry and swine

    DEFF Research Database (Denmark)

    Hald, Tine; Baggesen, Dorte Lau

    The purpose of this assessment was to identify public health risks linked to mechanically separated meat (MSM) types from pork and poultry and compare them with fresh meat, minced meat and meat preparations (non-MSM); and to select, rank and suggest objective measurement methods and values...... for parameters to distinguish MSM types. Microbial hazards in MSM are expected to be similar to those in non-MSM, although the risk of microbial growth increases with the degree of muscle fibre degradation, thus with the separation pressure. For the distinction between the different types of MSM and non-MSM...... chemical, histological, molecular, textural and rheological parameters were considered as potential indicators. The analysis of available published data suggested that calcium and, if confirmed cholesterol content, was the only appropriate chemical parameters which could be used to distinguish MSM from non-MSM...

  10. HIV Testing Preferences Among MSM Members of an LGBT Community Organization in Los Angeles.

    Science.gov (United States)

    Medline, Alexandra; Daniels, Joseph; Marlin, Robert; Young, Sean; Wilson, Greg; Huang, Emily; Klausner, Jeffrey D

    Lack of regular HIV testing puts African American, Asian, and Latino men who have sex with men (MSM) at high risk for HIV infection. Rapid self-testing may be an effective option for these men. We explored acceptability, preferences, and usability of HIV self-test kits with MSM of color using semi-structured focus groups to discuss HIV testing history, reasons for testing, and self-testing preferences. Participants (n = 21) lived in Los Angeles, identified as MSM of color, and were 18-35 years of age. Discussions were audio-recorded, transcribed, and analyzed using grounded theory. Participants expressed needs for (a) accessibility, (b) privacy, (c) local support, and (d) access to testing professionals. Self-testing for HIV infection may be an effective method for high-risk MSM. Effective self-testing programs need to consider accessibility, confidentiality, and support to increase routine testing. Community-based organizations have an opportunity to increase HIV testing for MSM of color. Copyright © 2017 Association of Nurses in AIDS Care. Published by Elsevier Inc. All rights reserved.

  11. Recent mobile health interventions to support medication adherence among HIV-positive MSM.

    Science.gov (United States)

    Muessig, Kathryn E; LeGrand, Sara; Horvath, Keith J; Bauermeister, José A; Hightow-Weidman, Lisa B

    2017-09-01

    We describe recent mobile health (mHealth) interventions supporting antiretroviral therapy (ART) medication adherence among HIV-positive MSM. Keyword searches (1 January 2016-13 May 2017) identified 721 citations. Seven publications reporting on six studies met inclusion criteria. Five studies focused on MSM. Interventions primarily employed text messaging (n = 4), whereas two focused on smartphone apps and one on social media. Three studies measured intervention impact on adherence and found increased ART use intentions (n = 1), self-reported adherence (n = 1), and viral suppression (n = 1, no control group). Other mHealth interventions for HIV-positive MSM focused on status disclosure and reducing sexual risk. mHealth interventions to support ART adherence among MSM show acceptability, feasibility, and preliminary efficacy. No recent mHealth interventions for MSM measured impact on viral suppression compared with a control condition despite earlier (pre-2015) evidence for efficacy. Studies are underway that include multiple features designed to improve adherence within complex smartphone or internet-based platforms. Areas for future growth include overcoming measurement and engagement challenges, developing tools for coordinating patient and provider adherence data, testing combination interventions, and adapting efficacious interventions for new languages and geographic settings.

  12. The MsmX ATPase plays a crucial role in pectin mobilization by Bacillus subtilis.

    Directory of Open Access Journals (Sweden)

    Mário J Ferreira

    Full Text Available Carbohydrates from plant cell walls are often found as heteropolysaccharides intertwined with each other. For competitive advantage against other microorganisms, and ability to fully exploit available carbon and energy sources, Bacillus subtilis possesses a high number of proteins dedicated to the uptake of mono- and oligosaccharides. Here, we characterize transporter complexes, belonging to the ATP-binding cassette (ABC superfamily, involved in the uptake of oligosaccharides commonly found in pectin. The uptake of these carbohydrates is shown to be MsmX-dependent, assigning a key role in pectin mobilization for MsmX, a multipurpose ATPase serving several distinct ABC-type I sugar importers. Mutagenesis analysis of the transmembrane domains of the AraNPQ MsmX-dependent importer revealed putative residues for MsmX interaction. Interestingly however, although MsmX is shown to be essential for energizing various ABC transporters we found that a second B. subtilis ATPase, YurJ, is able to complement its function when placed in trans at a different locus of the chromosome.

  13. Cross-cultural differences in item and background memory: examining the influence of emotional intensity and scene congruency.

    Science.gov (United States)

    Mickley Steinmetz, Katherine R; Sturkie, Charlee M; Rochester, Nina M; Liu, Xiaodong; Gutchess, Angela H

    2017-11-25

    After viewing a scene, individuals differ in what they prioritise and remember. Culture may be one factor that influences scene memory, as Westerners have been shown to be more item-focused than Easterners (see Masuda, T., & Nisbett, R. E. (2001). Attending holistically versus analytically: Comparing the context sensitivity of Japanese and Americans. Journal of Personality and Social Psychology, 81, 922-934). However, cultures may differ in their sensitivity to scene incongruences and emotion processing, which may account for cross-cultural differences in scene memory. The current study uses hierarchical linear modeling (HLM) to examine scene memory while controlling for scene congruency and the perceived emotional intensity of the images. American and East Asian participants encoded pictures that included a positive, negative, or neutral item placed on a neutral background. After a 20-min delay, participants were shown the item and background separately along with similar and new items and backgrounds to assess memory specificity. Results indicated that even when congruency and emotional intensity were controlled, there was evidence that Americans had better item memory than East Asians. Incongruent scenes were better remembered than congruent scenes. However, this effect did not differ by culture. This suggests that Americans' item focus may result in memory changes that are robust despite variations in scene congruency and perceived emotion.

  14. Acoustic simulation in realistic 3D virtual scenes

    Science.gov (United States)

    Gozard, Patrick; Le Goff, Alain; Naz, Pierre; Cathala, Thierry; Latger, Jean

    2003-09-01

    The simulation workshop CHORALE developed in collaboration with OKTAL SE company for the French MoD is used by government services and industrial companies for weapon system validation and qualification trials in the infrared domain. The main operational reference for CHORALE is the assessment of the infrared guidance system of the Storm Shadow missile French version, called Scalp. The use of CHORALE workshop is now extended to the acoustic domain. The main objective is the simulation of the detection of moving vehicles in realistic 3D virtual scenes. This article briefly describes the acoustic model in CHORALE. The 3D scene is described by a set of polygons. Each polygon is characterized by its acoustic resistivity or its complex impedance. Sound sources are associated with moving vehicles and are characterized by their spectra and directivities. A microphone sensor is defined by its position, its frequency band and its sensitivity. The purpose of the acoustic simulation is to calculate the incoming acoustic pressure on microphone sensors. CHORALE is based on a generic ray tracing kernel. This kernel possesses original capabilities: computation time is nearly independent on the scene complexity, especially the number of polygons, databases are enhanced with precise physical data, special mechanisms of antialiasing have been developed that enable to manage very accurate details. The ray tracer takes into account the wave geometrical divergence and the atmospheric transmission. The sound wave refraction is simulated and rays cast in the 3D scene are curved according to air temperature gradient. Finally, sound diffraction by edges (hill, wall,...) is also taken into account.

  15. Combined influence of visual scene and body tilt on arm pointing movements: gravity matters!

    Science.gov (United States)

    Scotto Di Cesare, Cécile; Sarlegna, Fabrice R; Bourdin, Christophe; Mestre, Daniel R; Bringoux, Lionel

    2014-01-01

    Performing accurate actions such as goal-directed arm movements requires taking into account visual and body orientation cues to localize the target in space and produce appropriate reaching motor commands. We experimentally tilted the body and/or the visual scene to investigate how visual and body orientation cues are combined for the control of unseen arm movements. Subjects were asked to point toward a visual target using an upward movement during slow body and/or visual scene tilts. When the scene was tilted, final pointing errors varied as a function of the direction of the scene tilt (forward or backward). Actual forward body tilt resulted in systematic target undershoots, suggesting that the brain may have overcompensated for the biomechanical movement facilitation arising from body tilt. Combined body and visual scene tilts also affected final pointing errors according to the orientation of the visual scene. The data were further analysed using either a body-centered or a gravity-centered reference frame to encode visual scene orientation with simple additive models (i.e., 'combined' tilts equal to the sum of 'single' tilts). We found that the body-centered model could account only for some of the data regarding kinematic parameters and final errors. In contrast, the gravity-centered modeling in which the body and visual scene orientations were referred to vertical could explain all of these data. Therefore, our findings suggest that the brain uses gravity, thanks to its invariant properties, as a reference for the combination of visual and non-visual cues.

  16. Combined influence of visual scene and body tilt on arm pointing movements: gravity matters!

    Directory of Open Access Journals (Sweden)

    Cécile Scotto Di Cesare

    Full Text Available Performing accurate actions such as goal-directed arm movements requires taking into account visual and body orientation cues to localize the target in space and produce appropriate reaching motor commands. We experimentally tilted the body and/or the visual scene to investigate how visual and body orientation cues are combined for the control of unseen arm movements. Subjects were asked to point toward a visual target using an upward movement during slow body and/or visual scene tilts. When the scene was tilted, final pointing errors varied as a function of the direction of the scene tilt (forward or backward. Actual forward body tilt resulted in systematic target undershoots, suggesting that the brain may have overcompensated for the biomechanical movement facilitation arising from body tilt. Combined body and visual scene tilts also affected final pointing errors according to the orientation of the visual scene. The data were further analysed using either a body-centered or a gravity-centered reference frame to encode visual scene orientation with simple additive models (i.e., 'combined' tilts equal to the sum of 'single' tilts. We found that the body-centered model could account only for some of the data regarding kinematic parameters and final errors. In contrast, the gravity-centered modeling in which the body and visual scene orientations were referred to vertical could explain all of these data. Therefore, our findings suggest that the brain uses gravity, thanks to its invariant properties, as a reference for the combination of visual and non-visual cues.

  17. Correlates of condomless anal sex among men who have sex with men (MSM) in Tijuana, Mexico: The role of public sex venues.

    Science.gov (United States)

    Semple, Shirley J; Pitpitan, Eileen V; Goodman-Meza, David; Strathdee, Steffanie A; Chavarin, Claudia V; Rangel, Gudelia; Torres, Karla; Patterson, Thomas L

    2017-01-01

    Condomless anal sex between male partners is the primary risk factor for HIV transmission among men who have sex with men (MSM). Correlates of condomless anal sex have been well-studied in developed countries, but they have received less attention in lower-to-middle income countries (LMIC), where MSM are often subject to stigma, discrimination, intolerance, and even the criminalization of same sex behavior. In Mexico, a LMIC where traditional views on homosexuality are common, HIV prevalence among MSM is high (16.9%), yet little research has been conducted on the correlates of condomless anal sex in this high-risk population. The present study examined correlates of condomless anal sex among 201 MSM recruited in Tijuana, Mexico, with a focus on the role of public sex venues in relation to sexual risk behavior. Eligibility requirements were: biologically male, 18 years of age or older, resident of Tijuana, and self-reported anal or oral sex with a male partner in the past year. Participants completed an interviewer-administered, demographic and psychosocial survey, and were tested for HIV and syphilis. A hierarchical multiple linear regression model was tested to identify correlates of condomless anal sex. Thirty-eight percent of participants (N = 76) reported condomless anal sex with a male partner in the past 2 months. Higher levels of condomless anal sex were associated with higher levels of depressive symptoms, greater sexual compulsivity, and more frequent seeking out of sex partners in a public venue in the past 2 months. In view of these findings, we recommend the development of multi-level, "combination" interventions, which in the Mexican context should include enhanced condom promotion and distribution, improved availability and access to mental health treatment and counseling services, and expanded HIV/STI testing in public venues.

  18. A time-critical adaptive approach for visualizing natural scenes on different devices.

    Science.gov (United States)

    Dong, Tianyang; Liu, Siyuan; Xia, Jiajia; Fan, Jing; Zhang, Ling

    2015-01-01

    To automatically adapt to various hardware and software environments on different devices, this paper presents a time-critical adaptive approach for visualizing natural scenes. In this method, a simplified expression of a tree model is used for different devices. The best rendering scheme is intelligently selected to generate a particular scene by estimating the rendering time of trees based on their visual importance. Therefore, this approach can ensure the reality of natural scenes while maintaining a constant frame rate for their interactive display. To verify its effectiveness and flexibility, this method is applied in different devices, such as a desktop computer, laptop, iPad and smart phone. Applications show that the method proposed in this paper can not only adapt to devices with different computing abilities and system resources very well but can also achieve rather good visual realism and a constant frame rate for natural scenes.

  19. Serosorting and HIV/STI Infection among HIV-Negative MSM and Transgender People: A Systematic Review and Meta-Analysis to Inform WHO Guidelines

    Science.gov (United States)

    Kennedy, Caitlin E.; Bernard, Laura J.; Muessig, Kathryn E.; Konda, Kelika A.; Akl, Elie A.; Lo, Ying-Ru; Gerbase, Antonio; O'Reilly, Kevin R.

    2013-01-01

    We conducted a systematic review and meta-analysis to assess the association between serosorting and HIV infection, sexually transmitted infections (STIs), and quality of life among men who have sex with men (MSM) and transgender people. Two reviewers independently screened abstracts and abstracted data. Meta-analyses were conducted using random effects models. Of 310 citations reviewed, 4 observational studies, all with MSM, met inclusion criteria. Compared to consistent condom use, serosorting was associated with increased risk of HIV (3 studies, odds ratio (OR): 1.80, 95% confidence interval (CI):1.21–2.70) and bacterial STIs (1 study, OR: 1.62, 95% CI: 1.44–1.83). Compared to no condom use, serosorting was associated with reduced risk of HIV (3 studies, OR: 0.46, 95% CI: 0.25–0.83) and bacterial STIs (1 study, OR: 0.81, 95% CI: 0.73–0.91). Among HIV-negative MSM, condom use appears to be more protective against HIV and STIs than serosorting and should be encouraged. However, serosorting may be better than no condom use as a harm reduction strategy. PMID:26316960

  20. Psychological and behavioral moderators of the relationship between trauma severity and HIV transmission risk behavior among MSM with a history of childhood sexual abuse.

    Science.gov (United States)

    Batchelder, Abigail W; Ehlinger, Peter P; Boroughs, Michael S; Shipherd, Jillian C; Safren, Steven A; Ironson, Gail H; O'Cleirigh, Conall

    2017-10-01

    Childhood sexual abuse (CSA) is associated with post-traumatic stress disorder (PTSD), which can be associated with condomless sex among men who have sex with men (MSM). However, the impact of moderating factors on the relationship between PTSD symptom severity and condomless sex is poorly understood. We examined whether PTSD symptom severity was associated with condomless sex among MSM with CSA histories, and whether substance dependence, self-esteem, and distress tolerance moderated that relationship (n = 288). Notably, no direct relationship between PTSD symptom severity and condomless sex was found. Adjusted models indicated that condomless sex was differentially impacted by PTSD symptom severity among those without substance dependence (ΔR 2  = 0.03, p = 0.034) and, counterintuitively, those with high self-esteem (ΔR 2  = 0.07, p = 0.005). PTSD symptom severity was associated with condomless sex across levels of distress tolerance. Findings indicate that substance use, self-esteem, and distress tolerance should be targeted in high-risk MSM with CSA even if they do not have PTSD.

  1. Serosorting and HIV/STI Infection among HIV-Negative MSM and Transgender People: A Systematic Review and Meta-Analysis to Inform WHO Guidelines

    Directory of Open Access Journals (Sweden)

    Caitlin E. Kennedy

    2013-01-01

    Full Text Available We conducted a systematic review and meta-analysis to assess the association between serosorting and HIV infection, sexually transmitted infections (STIs, and quality of life among men who have sex with men (MSM and transgender people. Two reviewers independently screened abstracts and abstracted data. Meta-analyses were conducted using random effects models. Of 310 citations reviewed, 4 observational studies, all with MSM, met inclusion criteria. Compared to consistent condom use, serosorting was associated with increased risk of HIV (3 studies, odds ratio (OR: 1.80, 95% confidence interval (CI:1.21–2.70 and bacterial STIs (1 study, OR: 1.62, 95% CI: 1.44–1.83. Compared to no condom use, serosorting was associated with reduced risk of HIV (3 studies, OR: 0.46, 95% CI: 0.25–0.83 and bacterial STIs (1 study, OR: 0.81, 95% CI: 0.73–0.91. Among HIV-negative MSM, condom use appears to be more protective against HIV and STIs than serosorting and should be encouraged. However, serosorting may be better than no condom use as a harm reduction strategy.

  2. The Associations of Resilience and HIV Risk Behaviors Among Black Gay, Bisexual, Other Men Who Have Sex with Men (MSM) in the Deep South: The MARI Study.

    Science.gov (United States)

    McNair, Obie S; Gipson, June A; Denson, Damian; Thompson, Darwin V; Sutton, Madeline Y; Hickson, DeMarc A

    2017-08-30

    Resilience is an understudied intrapersonal factor that may reduce HIV risk among men who have sex with men (MSM). Multivariable Poisson regression models were used to estimate the prevalence ratio (PR) of sexual risk behaviors, HIV prevalence, and history of sexually transmitted infections (STIs) with resilience scores in a population-based study among 364 black MSM in the Deep South. Participants with higher resilience scores had a lower prevalence of condomless anal sex with casual sexual partners in past 12 months (PR = 0.80, p value = 0.001) and during their last sexual encounter (PR = 0.81; p value = 0.009). Resilience was inversely associated with a lower prevalence of condomless anal sex with main sexual partners, participating in a sex party/orgy and having a STI in the past 12 months. Resilience may have a protective effect on HIV among black MSM, especially in the Deep South, and should be further explored in studies with prospective designs.

  3. HIV knowledge and associated factors among internet-using men who have sex with men (MSM in South Africa and the United States.

    Directory of Open Access Journals (Sweden)

    Bradley H Wagenaar

    Full Text Available We compared factors associated with low HIV/AIDS knowledge among internet-using MSM in South Africa and the United States.1,154 MSM in the US and 439 MSM in South Africa, recruited through Facebook.com, completed an online survey using a US-validated HIV knowledge scale (HIV-KQ-18. Separate multivariable logistic regression models were built, one for the US and one for South Africa, using a dichotomized variable of scoring less than and equal to 13/18 ("low knowledge" on the HIV-KQ-18 as outcome.Median knowledge scores were 16/18 for both groups of respondents. For South African MSM, factors associated with low knowledge were: a high school education or less (adjusted odds ratio [aOR]: 2.5, 95% confidence interval [CI]: 1.4–4.6, not using condom-compatible lubrication during last anal sex with another man (aOR: 1.9, CI: 1.0–3.5, number of gay or bisexual acquaintances (aOR: 0.89, CI: 0.81–0.99, being unemployed (aOR: 2.2, CI: 1.0–4.6, and testing HIV negative (aOR: 0.30, CI: 0.16–0.59 or testing HIV positive (aOR: 0.15, CI: 0.03–0.74 compared to those never HIV tested. For US MSM, associated factors were: a high school education or less (aOR: 2.7, CI: 1.9–3.8, low pride and acceptance of homosexuality (aOR: 1.3, CI: 1.2–1.5, age 18–24 (aOR: 2.3, CI: 1.3–3.8 or age 50+ (aOR: 3.2, CI: 1.6–6.3 compared to age 25–29, Hispanic ethnicity compared to white non-Hispanic (aOR: 1.9, CI: 1.1–3.2, and testing HIV positive (aOR: 0.34, CI: 0.16–0.69 or testing HIV negative (aOR: 0.59, CI: 0.39–0.89 compared to those never HIV tested [corrected].Those developing programs for MSM in South Africa should weigh these data and other relevant factors, and might consider focusing education services towards MSM with limited education, less integration into gay/bisexual communities, no HIV testing history, limited use of condom-compatible lube, and the unemployed. In the United States, Hispanic MSM, those with limited education, no HIV

  4. Gay Apps for Seeking Sex Partners in China: Implications for MSM Sexual Health.

    Science.gov (United States)

    Bien, Cedric H; Best, John M; Muessig, Kathryn E; Wei, Chongyi; Han, Larry; Tucker, Joseph D

    2015-06-01

    Anti-gay stigma and harsh local environments in many low and middle-income countries (LMIC) encourage men who have sex with men (MSM) partner-seeking mobile application (gay app) use. To investigate the sexual risk profiles of gay app users and guide future HIV prevention programs, we conducted a cross-sectional online survey among 1,342 MSM in China examining associations between gay app use and sexual behaviors, including HIV and sexually transmitted disease testing. Compared to non-app users, app users were more likely to be younger, better educated, "out" about their sexual orientation, and single. They were also more likely to report multiple recent sex partners and HIV testing, but there was no difference in condomless sex between the two groups. Future research among MSM in LMIC is needed to characterize gay app use and explore its potential for future public health interventions.

  5. MTF characteristics of a Scophony scene projector

    Science.gov (United States)

    Schildwachter, Eric F.; Boreman, Glenn D.

    1991-09-01

    The Scophony scene projector has been examined in detail. Modulation transfer function was measured and found to be significantly lower than expected. The discrepancy is shown to be due to variation in the Bragg angle with input frequency. Experimental data is compared with calculated performance.

  6. 3-D Scene Reconstruction from Aerial Imagery

    Science.gov (United States)

    2012-03-01

    navigate along interstate routes at speeds in excess of 110 mph, and the inclusion of the first down line in televised football games [28]. These...roughly 2000 feet above the target based on the Sadr City scene dimensions and scaling fac - tors. Images were rendered at a resolution of 1000×1000 as

  7. Vocational Guidance Requests within the International Scene

    Science.gov (United States)

    Goodman, Jane; Gillis, Sarah

    2009-01-01

    This article summarizes the work of a diverse group of researchers and practitioners from 5 continents on "Vocational Guidance Requests Within the International Scene" presented in the discussion group at a symposium of the International Association for Educational and Vocational Guidance, the Society for Vocational Psychology, and the…

  8. Behind the scenes at the LHC inauguration

    CERN Multimedia

    2008-01-01

    On 21 October the LHC inauguration ceremony will take place and people from all over CERN have been busy preparing. With delegations from 38 countries attending, including ministers and heads of state, the Bulletin has gone behind the scenes to see what it takes to put together an event of this scale.

  9. Parafoveal Semantic Processing of Emotional Visual Scenes

    Science.gov (United States)

    Calvo, Manuel G.; Lang, Peter J.

    2005-01-01

    The authors investigated whether emotional pictorial stimuli are especially likely to be processed in parafoveal vision. Pairs of emotional and neutral visual scenes were presented parafoveally (2.1[degrees] or 2.5[degrees] of visual angle from a central fixation point) for 150-3,000 ms, followed by an immediate recognition test (500-ms delay).…

  10. Perceived glossiness in high dynamic range scenes.

    Science.gov (United States)

    Doerschner, Katja; Maloney, Laurence T; Boyaci, Huseyin

    2010-01-01

    We investigated how spatial pattern, background, and dynamic range affect perceived gloss in brightly lit real scenes. Observers viewed spherical objects against uniform backgrounds. There were three possible objects. Two were black matte spheres with circular matte white dots painted on them (matte-dot spheres). The third sphere was painted glossy black (glossy black sphere). Backgrounds were either black or white matte, and observers saw each of the objects in turn on each background. Scenes were illuminated by an intense collimated source. On each trial, observers matched the apparent albedo of the sphere to an albedo reference scale and its apparent gloss to a gloss reference scale. We found that matte-dot spheres and the black glossy sphere were perceived as glossy on both backgrounds. All spheres were judged to be significantly glossier when in front of the black background. In contrast with previous research using conventional computer displays, we find that background markedly affects perceived gloss. This finding is surprising because darker surfaces are normally perceived as glossier (F. Pellacini, J. A. Ferwerda, & D. P. Greenberg, 2000). We conjecture that there are cues to surface material signaling glossiness present in high dynamic range scenes that are absent or weak in scenes presented using conventional computer displays.

  11. OpenSceneGraph 3 Cookbook

    CERN Document Server

    Wang, Rui

    2012-01-01

    This is a cookbook full of recipes with practical examples enriched with code and the required screenshots for easy and quick comprehension. You should be familiar with the basic concepts of the OpenSceneGraph API and should be able to write simple programs. Some OpenGL and math knowledge will help a lot, too.

  12. High HIV Prevalence among MSM in Jamaica is associated with Social Vulnerability and other Sexually Transmitted Infections

    Science.gov (United States)

    Figueroa, JP; Weir, SS; Jones-Cooper, C; Byfield, L; Hobbs, MM; McKnight, I; Cummings, S

    2013-01-01

    Background HIV prevalence among men who have sex with men (MSM) is thought to be high in Jamaica. The objective of this study was to estimate HIV prevalence and identify risk factors in order to improve prevention approaches. Methods With the help of influential MSM, an experienced research nurse approached MSM in four parishes to participate in a cross-sectional survey in 2007. MSM were interviewed and blood taken for HIV and syphilis tests, and urine taken for gonorrhoea, Chlamydia and Trichomonas testing using transcription-mediated amplification assays. A structured questionnaire was administered by the nurse. Results One third (65 of 201; 32%, 95% Confidence Interval (CI) 25.2% – 47.9%) of MSM were HIV positive. Prevalence of other sexually transmitted infections (STI) was: Chlamydia 11%, syphilis 6%, gonorrhea 3.5% and Trichomonas 0%. One third (34%) of MSM identified themselves as being homosexual, 64% as bisexual and 1.5% as heterosexual. HIV positive MSM were significantly more likely to have ever been told by a doctor that they had a STI (48% vs. 27%, OR 2.48 CI 1.21 – 5.04, p=0.01) and to be the receptive sexual partner at last sex (41% vs. 23%, OR 2.41 CI 1.21 – 4.71, p=0.008). MSM who were of low socio-economic status, ever homeless and victims of physical violence were twice as likely to be HIV positive. The majority (60%) of HIV positive MSM had not disclosed their status to their partner and over 50% were not comfortable disclosing their status to anyone. Conclusions The high HIV prevalence among MSM is an important factor driving the HIV epidemic in Jamaica. More effective ways need to be found to reduce the high prevalence of HIV among MSM including measures to reduce their social vulnerability, combat stigma and discrimination and empower them to practice safe sex. PMID:24756602

  13. Hepatitis C virus infection and its relationship to certain sexual practices in men-who-have-sex-with-men in Spain: results from the European MSM internet survey (EMIS).

    Science.gov (United States)

    Fernández-Dávila, Percy; Folch, Cinta; Ferrer, Laia; Soriano, Raúl; Diez, Mercedes; Casabona, Jordi

    2015-05-01

    To compare sexual practices and risk behaviours between MSM who were first diagnosed with hepatitis C (HCV) in the previous 12 months and those who were never diagnosed; and, to identify factors associated with a diagnosis of HCV. The European-MSM-Internet-Survey (EMIS) was implemented for 3 months during 2010, mainly on websites for MSM. Data on socio-demographic characteristics, sexual behaviour, drug use, STI history, and other sexual health variables were collected. The Chi-square test and logistic regression analysis were used to analyse the data. Data from 13,111 respondents were analysed. The proportion of MSM who had ever been diagnosed with HCV infection was 1.9% (n=250), and of those currently infected with the virus was 0.6% (n=78). The percentage of those first diagnosed in the last 12 months was 0.4% (n=46), of whom 70% were HIV-negative and 22% had HIV coinfection. Having a first diagnosis of HCV in the last 12 months was more common among HIV-positive than among HIV-negative MSM (0.9% vs 0.4%) and among MSM born abroad than among Spanish-born (0.7% vs 0.3%). MSM diagnosed with HCV in the last 12 months were more likely to have had: more than 10 sexual partners, sex abroad, receptive anal intercourse, insertive/receptive fisting, and unprotected anal intercourse with non-steady partners of unknown or discordant HIV-status. Likewise, they reported more frequent visits to sex-focused venues, higher drug use, as well as a higher proportion of STI diagnosis. In the multivariate model, visiting a public sex-focused venue, practicing receptive fisting, using erection enhancing medication and having a diagnosis of syphilis were independently associated with a first diagnosis of HCV in the last 12 months. HCV infection does not seem to be restricted to HIV-infected MSM. Certain sexual behaviour (fisting, visiting sex-focused venues), drug use, and ulcerative STI seem to be associated with a diagnosis of HCV. Copyright © 2014 Elsevier España, S.L.U. y

  14. Negotiating exclusion: MSM, identity, and blood policy in the age of AIDS.

    Science.gov (United States)

    Martucci, Jessica

    2010-04-01

    In the US, blood donors face a variety of restrictions that leave many people excluded entirely from the donor pool. This paper explores the specific circumstances and meanings surrounding the donor ban on Men-who-have-Sex-with-Men (MSM). The ban on MSM is one of the few existing donor guidelines to receive considerable criticism on grounds that it effectively prohibits any sexually active gay man from donating blood and thus discriminates against gays. Due in part to these questions of fairness, the Blood Products Advisory Committee (BPAC) of the Food and Drug Administration (FDA) met to reconsider the decades-old policy, first in 1997 and again in 2000. The FDA asked its advisory committee to address the efficacy and utility of the MSM ban in light of technological developments in blood-banking, epidemiological data on the spread of HIV, and mounting pressures from gay rights and blood-banking organizations to update the policy. Through a detailed reading of meeting and conference transcripts that took place between 1997 and 2000, I argue that 'MSM' became a contested definitional category during the FDA's reappraisal of the policy. During and between the Committee's discussions, presenters and experts debated the differences between sexual behavior and sexual identity in relation to HIV and, eventually, HHV-8, a virus known to cause Kaposi's sarcoma in immunosuppressed individuals. I argue that the underlying flexibility in the meanings behind the term 'MSM' allowed Committee members, in the end, to retract their more nuanced discussions of human behavior and HIV and to uphold the contested policy. Finally, I suggest how the debates surrounding the MSM donor ban can help us to better understand the place of sexuality in discussions and claims of biopolitical citizenship in early 21st-century America.

  15. The experiences of ethnic minority MSM using NHS sexual health clinics in Britain.

    Science.gov (United States)

    McKeown, Eamonn; Doerner, Rita; Nelson, Simon; Low, Nicola; Robinson, Angela; Anderson, Jane; Elford, Jonathan

    2012-12-01

    To compare the experiences of ethnic minority and white British men who have sex with men (MSM) who attend NHS sexual health clinics in Britain. In 2007-2008, a national sample of MSM living in Britain was recruited through websites, in sexual health clinics, bars, clubs and other venues. Men completed an online survey, which included questions about their experience of attending an NHS sexual health clinic. Analysis is restricted to 363 ethnic minority MSM and 4776 white British MSM who had attended an NHS sexual health clinic in the 12 months before the survey. Compared with white British men, men from an Indian, Pakistani or Bangladeshi background were more likely to be very anxious about attending the clinic (adjusted OR (aOR) 2.58, 95% CI 1.63 to 4.07), express concerns about being overheard at reception (aOR 1.68, 95% CI 1.10 to 2.58), be uncomfortable in the waiting area (aOR 2.08, 95% CI 1.35 to 3.22) or be afraid that people in their community would find out that they have sex with men (aOR 7.70, 95% CI 4.49 to 13.22). The adjusted ORs for being afraid that people in their community would find out that they have sex with men were also elevated for black Caribbean, black African, Chinese and other Asian men. Sexual health clinics should be aware that some ethnic minority MSM, particularly those from an Indian, Pakistani or Bangladeshi background, have heightened concerns about clinic attendance and confidentiality compared with white British MSM.

  16. HIV and STD status among MSM and attitudes about Internet partner notification for STD exposure.

    Science.gov (United States)

    Mimiaga, Matthew J; Tetu, Ashley M; Gortmaker, Steven; Koenen, Karestan C; Fair, Andrew D; Novak, David S; Vanderwarker, Rodney; Bertrand, Thomas; Adelson, Stephan; Mayer, Kenneth H

    2008-02-01

    This study assessed the acceptability and perceived utility of Internet-based partner notification (PN) of sexually transmitted disease (STD) exposure for men who have sex with men (MSM) by human immunodeficiency virus (HIV) serostatus. We recruited 1848 US MSM via a banner advertisement posted on an MSM website for meeting sexual partners between October and November 2005. Even though there was broad acceptance of a PN e-mail across HIV serostatus groups, HIV-infected men rated the importance of each component (e.g., information about where to get tested/treated, additional education regarding the STD exposed to, a mechanism for verifying the authenticity of the PN e-mail) lower than HIV-uninfected or status-unknown participants (all P's exposure in the future), and were less likely to inform their partners of possible STD exposure via an Internet notification system in the future (all P's <0.01). A similar trend emerged about men who reported not having a previous STD compared with those who did. Men who reported no previous STD found Internet PN more acceptable. Overall, this study documents broad acceptance of Internet PN by at-risk MSM, regardless of HIV serostatus, including a willingness to receive or initiate PN-related e-mail. If public health officials consider using Internet notification services, they may need to anticipate and address concerns of HIV-infected MSM, and will need to use a culturally-sensitive, social marketing campaign to ensure that those who may benefit from these services are willing to use this modality for PN. Internet PN should be considered as a tool to decrease rising STD and HIV rates among MSM who use the Internet to meet sexual partners.

  17. Caliber Corrected Markov Modeling (C2M2): Correcting Equilibrium Markov models

    OpenAIRE

    Dixit, Purushottam D.; Dill, Ken A

    2017-01-01

    Rate processes are often modeled using Markov-State Models (MSM). Suppose you know a prior MSM, and then learn that your prediction of some particular observable rate is wrong. What is the best way to correct the whole MSM? For example, molecular dynamics simulations of protein folding may sample many microstates, possibly giving correct pathways through them, while also giving the wrong overall folding rate, when compared to experiment. Here, we describe Caliber Corrected Markov Modeling (C2...

  18. A graph theoretic approach to scene matching

    Science.gov (United States)

    Ranganath, Heggere S.; Chipman, Laure J.

    1991-08-01

    The ability to match two scenes is a fundamental requirement in a variety of computer vision tasks. A graph theoretic approach to inexact scene matching is presented which is useful in dealing with problems due to imperfect image segmentation. A scene is described by a set of graphs, with nodes representing objects and arcs representing relationships between objects. Each node has a set of values representing the relations between pairs of objects, such as angle, adjacency, or distance. With this method of scene representation, the task in scene matching is to match two sets of graphs. Because of segmentation errors, variations in camera angle, illumination, and other conditions, an exact match between the sets of observed and stored graphs is usually not possible. In the developed approach, the problem is represented as an association graph, in which each node represents a possible mapping of an observed region to a stored object, and each arc represents the compatibility of two mappings. Nodes and arcs have weights indicating the merit or a region-object mapping and the degree of compatibility between two mappings. A match between the two graphs corresponds to a clique, or fully connected subgraph, in the association graph. The task is to find the clique that represents the best match. Fuzzy relaxation is used to update the node weights using the contextual information contained in the arcs and neighboring nodes. This simplifies the evaluation of cliques. A method of handling oversegmentation and undersegmentation problems is also presented. The approach is tested with a set of realistic images which exhibit many types of sementation errors.

  19. Simulation of optimum parameters for GaN MSM UV photodetector

    Energy Technology Data Exchange (ETDEWEB)

    Alhelfi, Mohanad A., E-mail: mhad12344@gmail.com; Ahmed, Naser M., E-mail: nas-tiji@yahoo.com; Hashim, M. R., E-mail: roslan@usm.my; Hassan, Z., E-mail: zai@usm.my [Institue of Nano-Optoelectronics Research and Technology (INOR), School of Physics, Universiti Sains Malaysia 11800 Penang (Malaysia); Al-Rawi, Ali Amer, E-mail: aliamer@unimap.edu.my [School of Computer and Communication Eng. 3st Floor, Pauh Putra Main Campus 02600 Arau, Perlis Malaysia (Malaysia)

    2016-07-06

    In this study the optimum parameters of GaN M-S-M photodetector are discussed. The evaluation of the photodetector depends on many parameters, the most of the important parameters the quality of the GaN film and others depend on the geometry of the interdigited electrode. In this simulation work using MATLAB software with consideration of the reflection and absorption on the metal contacts, a detailed study involving various electrode spacings (S) and widths (W) reveals conclusive results in device design. The optimum interelectrode design for interdigitated MSM-PD has been specified and evaluated by effect on quantum efficiency and responsivity.

  20. PRACE resources to study extreme natural events: the SCENE project

    Science.gov (United States)

    Fiori, Elisabetta; Galizia, Antonella; Danovaro, Emanuele; Clematis, Andrea; Bedrina, Tatiana; Parodi, Antonio

    2014-05-01

    Forecasting severe storms and floods is one of the main challenges of 21th century. Floods are the most dangerous meteorological hazard in the Mediterranean basins due to both the number of people affected and to the relatively high frequency by which human activities and goods suffer damages and losses. The numerical simulations of extreme events which happen over small basins as the Mediterranean ones are need a very fine-resolution in space and time and as a consequence considerable memory and computational power are required. Since the resources provided by the PRACE project represent the solution for satisfying such requirements, the Super Computing of Extreme Natural Events (SCENE) project has been proposed. SCENE aims to provide an advanced understanding of the intrinsic predictability of severe precipitation processes and the associated predictive ability of high-resolution meteorological models with a special focus on flash flood-producing storms in regions of complex orography (e.g. Mediterranean area) through the assessment of the role of both the convective and microphysical processes. The meteorological model considered in the project is the Weather Research and Forecasting (WRF) model, a state of the art mesoscale numerical weather prediction system designed to serve both operational forecasting and atmospheric research needs. Thus, among all the parameterizations available in the WRF model, the WRF Single-Moment 6-Class Scheme and the Thompson microphysics scheme will be adopted for the numerical simulations in combination with three different approaches for the treatment of the convective processes, that is the use of explicit method, Betts-Miller-Janjic Scheme and Kain-Fritsch. As for flash-flood producing storms, the project considers the recent sequence of extreme events occurred in the north-western portion of the Mediterranean sea; some of these events are the so-called critical cases of the DRIHM project (www.drihm.eu), i.e. selected severe

  1. HPV vaccine acceptability in HIV-infected and HIV negative men who have sex with men (MSM) in Ireland.

    Science.gov (United States)

    Sadlier, C; Lynam, A; O'Dea, S; Delamere, S; Quinlan, M; Clarke, S; Sheils, O; Bergin, C

    2016-06-02

    Background Men who have sex with men (MSM), particularly HIV-infected MSM are disproportionately affected by HPV infection and associated disease. The HPV vaccine has potential to greatly reduce the burden of HPV-associated disease including anal cancer in MSM. The efficacy of the HPV vaccine is dependent on high levels of vaccine uptake. The aim of this study was to examine HPV vaccine acceptability and factors influencing vaccine acceptability in MSM in Ireland. Methods A self-administered survey was distributed to HIV-infected and HIV negative MSM examining HPV vaccine acceptability and factors associated with vaccine acceptability. Logistic regression was used to identify key variables and predictors of HPV vaccine acceptability. Results 302 MSM participated in the study. Acceptability of HPV vaccine was 31% (unconditional), 51% (conditional on stated efficacy and a cost of €300), 65% (conditional on stated efficacy and a cost of €100) and 78% (conditional on stated efficacy and no cost). Cost was negatively associated with HPV vaccine acceptability (pHPV vaccine efficacy was significantly associated with vaccine acceptability, even in the context of associated cost (pHPV vaccine in MSM in Ireland is high based on no cost vaccine and on stated vaccine efficacy (78%). Cost is negatively associated with vaccine acceptability. Understanding levels of knowledge of HPV infection, HPV associated disease and attitudes toward HPV vaccination are important as they will contribute to HPV vaccine acceptability among MSM and will help guide effective preventive programs.

  2. Anal HPV 16 and 18 viral load: A comparison between HIV-negative and -positive MSM and association with persistence

    NARCIS (Netherlands)

    Marra, Elske; King, Audrey; van Logchem, Elske; van der Weele, Pascal; Mooij, Sofie H.; Heijman, Titia; Meijer, Chris J. L. M.; Verhagen, Dominique W. M.; van der Sande, Marianne A. B.; Schim van der Loeff, Maarten F.

    2018-01-01

    Does anal HPV viral load explain the difference in anal HPV persistence between HIV-negative and -positive men who have sex with men (MSM)? MSM 18 years were recruited in Amsterdam, the Netherlands, in 2010-2011. Anal self-swabs were collected every 6 months and genotyped

  3. Development and pilot testing of an intervention to promote care engagement and adherence among HIV-positive Kenyan MSM

    NARCIS (Netherlands)

    Graham, Susan M.; Micheni, Murugi; Kombo, Bernadette; van der Elst, Elisabeth M.; Mugo, Peter M.; Kivaya, Esther; Aunon, Frances; Kutner, Bryan; Sanders, Eduard J.; Simoni, Jane M.

    2015-01-01

    In many African settings, MSM are a stigmatized group whose access to and engagement in HIV care may be challenging. Our aim was to design a targeted, culturally appropriate intervention to promote care engagement and antiretroviral therapy (ART) adherence for MSM in coastal Kenya, and describe

  4. HPV seroconversion following anal and penile HPV infection in HIV-negative and HIV-infected MSM

    NARCIS (Netherlands)

    Mooij, Sofie H.; Landén, Olivia; van der Klis, Fiona R. M.; van der Sande, Marianne A. B.; de Melker, Hester E.; Xiridou, Maria; van Eeden, Arne; Heijman, Titia; Speksnijder, Arjen G. C. L.; Snijders, Peter J. F.; Schim van der Loeff, Maarten F.

    2014-01-01

    We assessed human papillomavirus (HPV) seroconversion following anal and penile HPV infection in HIV-negative and HIV-infected men who have sex with men (MSM). MSM aged ≥18 years were recruited in Amsterdam, the Netherlands (2010-2011), and followed up semiannually. Antibodies against 7 high-risk

  5. Accelerative and decelerative effects of hedonic valence and emotional arousal during visual scene processing.

    Science.gov (United States)

    Ihssen, Niklas; Keil, Andreas

    2013-01-01

    Perceptual processing of natural scene pictures is enhanced when the scene conveys emotional content. Such "motivated attention" to pleasant and unpleasant pictures has been shown to improve identification accuracy in non-speeded behavioural tasks. An open question is whether emotional content also modulates the speed of visual scene processing. In the present studies we show that unpleasant content reliably slowed two-choice categorization of pictures, irrespective of physical image properties, perceptual complexity, and categorization instructions. Conversely, pleasant content did not slow or even accelerated choice reactions, relative to neutral scenes. As indicated by lateralized readiness potentials, these effects occurred at cognitive processing rather than motor preparation/execution stages. Specifically, analysis of event-related potentials showed a prolongation of early scene discrimination for stimuli perceived as emotionally arousing, regardless of valence, and reflected in delayed peaks of the N1 component. In contrast, the timing of other processing steps, reflected in the P2 and late positive potential components and presumably related to post-discriminatory processes such as stimulus-response mapping, appeared to be determined by hedonic valence, with more pleasant scenes eliciting faster processing. Consistent with this model, varying arousal (low/high) within the emotional categories mediated the effects of valence on choice reaction speed. Functionally, arousal may prolong stimulus analysis in order to prevent erroneous and potentially harmful decisions. Pleasantness may act as a safety signal allowing rapid initiation of overt responses.

  6. Behind the scenes at Microcosm

    CERN Multimedia

    Emma Sanders

    2015-01-01

    Works advance at Microcosm in preparation for a progressive opening of the new exhibitions from mid-July onwards.   Construction of the section on the LHC experiments (mid-June 2015).   The Microcosm exhibition space is undergoing a total revamp and will feature many new objects. Old favourites, such as the LHC tunnel model and the Linac module, will be brought up to date with more modern exhibition techniques. Another main thrust of the new exhibitions will be the focus on the people that make CERN work. This is both to show the huge diversity of expertise needed at CERN and also to help students envisage where a career in physics or engineering might take them. With the project getting the go-ahead last autumn and the closure of the Globe for building works starting from May this year, the new Microcosm exhibition areas will open progressively as and when installations are completed to ensure that summer visitors who haven’t booked a guided tour will have something to ...

  7. Emotional and neutral scenes in competition: orienting, efficiency, and identification.

    Science.gov (United States)

    Calvo, Manuel G; Nummenmaa, Lauri; Hyönä, Jukka

    2007-12-01

    To investigate preferential processing of emotional scenes competing for limited attentional resources with neutral scenes, prime pictures were presented briefly (450 ms), peripherally (5.2 degrees away from fixation), and simultaneously (one emotional and one neutral scene) versus singly. Primes were followed by a mask and a probe for recognition. Hit rate was higher for emotional than for neutral scenes in the dual- but not in the single-prime condition, and A' sensitivity decreased for neutral but not for emotional scenes in the dual-prime condition. This preferential processing involved both selective orienting and efficient encoding, as revealed, respectively, by a higher probability of first fixation on--and shorter saccade latencies to--emotional scenes and by shorter fixation time needed to accurately identify emotional scenes, in comparison with neutral scenes.

  8. Computational Auditory Scene Analysis Based Perceptual and Neural Principles

    National Research Council Canada - National Science Library

    Wang, DeLiang

    2004-01-01

    .... This fundamental process of auditory perception is called auditory scene analysis. of particular importance in auditory scene analysis is the separation of speech from interfering sounds, or speech segregation...

  9. The Fisher Kernel Coding Framework for High Spatial Resolution Scene Classification

    Directory of Open Access Journals (Sweden)

    Bei Zhao

    2016-02-01

    Full Text Available High spatial resolution (HSR image scene classification is aimed at bridging the semantic gap between low-level features and high-level semantic concepts, which is a challenging task due to the complex distribution of ground objects in HSR images. Scene classification based on the bag-of-visual-words (BOVW model is one of the most successful ways to acquire the high-level semantic concepts. However, the BOVW model assigns local low-level features to their closest visual words in the “visual vocabulary” (the codebook obtained by k-means clustering, which discards too many useful details of the low-level features in HSR images. In this paper, a feature coding method under the Fisher kernel (FK coding framework is introduced to extend the BOVW model by characterizing the low-level features with a gradient vector instead of the count statistics in the BOVW model, which results in a significant decrease in the codebook size and an acceleration of the codebook learning process. By considering the differences in the distributions of the ground objects in different regions of the images, local FK (LFK is proposed for the HSR image scene classification method. The experimental results show that the proposed scene classification methods under the FK coding framework can greatly reduce the computational cost, and can obtain a better scene classification accuracy than the methods based on the traditional BOVW model.

  10. Simulating hyperspectral images for Martian 3D scenes.

    Science.gov (United States)

    Douté, S.

    2017-09-01

    We present a tool for simulating hyperspectral images for 3D Martian scenes. Several lines of development are considered for achieving a high degree of realism : high resolution digital elevation models, description of material distribution with fractal characteristics, bidirectional reflectance measured in the laboratory as a function of geometry and wavelength for a series analogue materials, mixing of spectral signatures at different scales, 3D radiative transfer between atmosphere and surface. The simulator addresses two main needs (i) developing and testing methods for the correction of atmospheric and photometric effects images taken by orbiter around Mars (ii) developing and testing methods for the linear and nonlinear spectral unmixing applied to hyperspectral images.

  11. Relaxation with Immersive Natural Scenes Presented Using Virtual Reality.

    Science.gov (United States)

    Anderson, Allison P; Mayer, Michael D; Fellows, Abigail M; Cowan, Devin R; Hegel, Mark T; Buckey, Jay C

    2017-06-01

    Virtual reality (VR) can provide exposure to nature for those living in isolated confined environments. We evaluated VR-presented natural settings for reducing stress and improving mood. There were 18 participants (9 men, 9 women), ages 32 ± 12 yr, who viewed three 15-min 360° scenes (an indoor control, rural Ireland, and remote beaches). Subjects were mentally stressed with arithmetic before scenes. Electrodermal activity (EDA) and heart rate variability measured psycho-physiological arousal. The Positive and Negative Affect Schedule and the 15-question Modified Reality Judgment and Presence Questionnaire (MRJPQ) measured mood and scene quality. Reductions in EDA from baseline were greater at the end of the natural scenes compared to the control scene (-0.59, -0.52, and 0.32 μS, respectively). The natural scenes reduced negative affect from baseline ( 1.2 and 1.1 points), but the control scene did not ( 0.4 points). MRJPQ scores for the control scene were lower than both natural scenes (4.9, 6.7, and 6.5 points, respectively). Within the two natural scenes, the preferred scene reduced negative affect ( 2.4 points) more than the second choice scene ( 1.8 points) and scored higher on the MRJPQ (6.8 vs. 6.4 points). Natural scene VR provided relaxation both objectively and subjectively, and scene preference had a significant effect on mood and perception of scene quality. VR may enable relaxation for people living in isolated confined environments, particularly when matched to personal preferences.Anderson AP, Mayer MD, Fellows AM, Cowan DR, Hegel MT, Buckey JC. Relaxation with immersive natural scenes presented using virtual reality. Aerosp Med Hum Perform. 2017; 88(6):520526.

  12. Scene-aware joint global and local homographic video coding

    Science.gov (United States)

    Peng, Xiulian; Xu, Jizheng; Sullivan, Gary J.

    2016-09-01

    Perspective motion is commonly represented in video content that is captured and compressed for various applications including cloud gaming, vehicle and aerial monitoring, etc. Existing approaches based on an eight-parameter homography motion model cannot deal with this efficiently, either due to low prediction accuracy or excessive bit rate overhead. In this paper, we consider the camera motion model and scene structure in such video content and propose a joint global and local homography motion coding approach for video with perspective motion. The camera motion is estimated by a computer vision approach, and camera intrinsic and extrinsic parameters are globally coded at the frame level. The scene is modeled as piece-wise planes, and three plane parameters are coded at the block level. Fast gradient-based approaches are employed to search for the plane parameters for each block region. In this way, improved prediction accuracy and low bit costs are achieved. Experimental results based on the HEVC test model show that up to 9.1% bit rate savings can be achieved (with equal PSNR quality) on test video content with perspective motion. Test sequences for the example applications showed a bit rate savings ranging from 3.7 to 9.1%.

  13. Collaborating Filtering Community Image Recommendation System Based on Scene

    Directory of Open Access Journals (Sweden)

    He Tao

    2017-01-01

    Full Text Available With the advancement of smart city, the development of intelligent mobile terminal and wireless network, the traditional text information service no longer meet the needs of the community residents, community image service appeared as a new media service. “There are pictures of the truth” has become a community residents to understand and master the new dynamic community, image information service has become a new information service. However, there are two major problems in image information service. Firstly, the underlying eigenvalues extracted by current image feature extraction techniques are difficult for users to understand, and there is a semantic gap between the image content itself and the user’s understanding; secondly, in community life of the image data increasing quickly, it is difficult to find their own interested image data. Aiming at the two problems, this paper proposes a unified image semantic scene model to express the image content. On this basis, a collaborative filtering recommendation model of fusion scene semantics is proposed. In the recommendation model, a comprehensiveness and accuracy user interest model is proposed to improve the recommendation quality. The results of the present study have achieved good results in the pilot cities of Wenzhou and Yan'an, and it is applied normally.

  14. HIV Testing among Men Who Have Sex with Men (MSM): Systematic Review of Qualitative Evidence

    Science.gov (United States)

    Lorenc, Theo; Marrero-Guillamon, Isaac; Llewellyn, Alexis; Aggleton, Peter; Cooper, Chris; Lehmann, Angela; Lindsay, Catriona

    2011-01-01

    We conducted a systematic review of qualitative evidence relating to the views and attitudes of men who have sex with men (MSM) concerning testing for HIV. Studies conducted in high-income countries (Organisation for Economic Co-operation and Development members) since 1996 were included. Seventeen studies were identified, most of gay or bisexual…

  15. Prevalence of HIV, syphilis, and other sexually transmitted infections among MSM from three cities in Panama.

    Science.gov (United States)

    Hakre, Shilpa; Arteaga, Griselda B; Núñez, Aurelio E; Arambu, Nelson; Aumakhan, Bulbulgul; Liu, Michelle; Peel, Sheila A; Pascale, Juan M; Scott, Paul T

    2014-08-01

    Respondent-driven sampling (RDS) was used to conduct a biobehavioral survey among men who have sex with men (MSM) in three cities in the Republic of Panama. We estimated the prevalence of HIV, syphilis, and other sexually transmitted infections (STIs), sociodemographic characteristics, and sexual risk behaviors. Among 603 MSM recruited, RDS-adjusted seroprevalences (95 % confidence intervals) were: HIV-David 6.6 % (2.2-11.4 %), Panama 29.4 % (19.7-39.7 %), and Colon 32.6 % (18.0-47.8 %); active syphilis-David 16.0 % (8.9-24.2 %), Panama 24.7 % (16.7-32.9 %), Colon 31.6 % (14.8-47.5 %); resolved HBV infection-David 10.0 % (4.8-16.8 %), Panama 29.4 % (20.0-38.3 %), and Colon 40.6 % (21.9-54.4 %); herpes simplex virus type 2-David 38.4 % (27.9-48.9 %), Panama 62.6 % (52.8-71.0 %), and Colon 72.9 % (57.4-85.8 %). At least a third of MSM in each city self-identified as heterosexual or bisexual. HIV prevalence is concentrated among MSM. Preventive interventions should focus on increasing HIV and syphilis testing, and increasing promotion of condom awareness and use.

  16. High Incidence of Asymptomatic Syphilis in HIV-Infected MSM Justifies Routine Screening

    NARCIS (Netherlands)

    Branger, Judith; van der Meer, Jan T. M.; van Ketel, Ruud J.; Jurriaans, Suzanne; Prins, Jan M.

    2009-01-01

    Background: Recently, the incidence of syphilis has risen, mainly among men having sex with men (MSM), many of whom are coinfected with HIV. Current guidelines recommend at least yearly syphilis testing in this group. In this study, we assessed the yield of routine syphilis screening in outpatient

  17. MSM optical detector on the basis of II-type ZnSe/ZnTe superlattice

    Energy Technology Data Exchange (ETDEWEB)

    Kuznetzov, P. I., E-mail: pik218@ire216.msk.su; Averin, S. V., E-mail: sva278@ire216.msk.su; Zhitov, V. A.; Zakharov, L. Yu.; Kotov, V. M. [Russian Academy of Sciences, Kotel’nikov Institute of Radioengineering and Electronics (Fryazino Branch) (Russian Federation)

    2017-02-15

    On the basis of a type-II ZnSe/ZnTe superlattice, a MSM (metal—semiconductor–metal) photodetector is fabricated and investigated. The detector features low dark currents and a high sensitivity. The spectral characteristic of the detector provides the possibility of the selective detection of three separate spectral portions of visible and near-infrared radiation.

  18. Responsivity Dependent Anodization Current Density of Nanoporous Silicon Based MSM Photodetector

    Directory of Open Access Journals (Sweden)

    Batool Eneaze B. Al-Jumaili

    2016-01-01

    Full Text Available Achieving a cheap and ultrafast metal-semiconductor-metal (MSM photodetector (PD for very high-speed communications is ever-demanding. We report the influence of anodization current density variation on the response of nanoporous silicon (NPSi based MSM PD with platinum (Pt contact electrodes. Such NPSi samples are grown from n-type Si (100 wafer using photoelectrochemical etching with three different anodization current densities. FESEM images of as-prepared samples revealed the existence of discrete pores with spherical and square-like shapes. XRD pattern displayed the growth of nanocrystals with (311 lattice orientation. The nanocrystallite sizes obtained using Scherrer formula are found to be between 20.8 nm and 28.6 nm. The observed rectifying behavior in the I-V characteristics is ascribed to the Pt/PSi/n-Si Schottky barrier formation, where the barrier height at the Pt/PSi interface is estimated to be 0.69 eV. Furthermore, this Pt/PSi/Pt MSM PD achieved maximum responsivity of 0.17 A/W and quantum efficiency as much as 39.3%. The photoresponse of this NPSi based MSM PD demonstrated excellent repeatability, fast response, and enhanced saturation current with increasing anodization current density.

  19. Risky Trade: Individual and Neighborhood-Level Socio-Demographics Associated with Transactional Sex among Urban African American MSM.

    Science.gov (United States)

    Stevens, Robin; Icard, Larry; Jemmott, John B; O'Leary, Ann; Rutledge, Scott; Hsu, Janet; Stephens-Shields, Alisa

    2017-08-01

    There is a clear, persistent association between poverty and HIV risk and HIV infection. Low educational attainment, neighborhood disadvantage, and residential instability are ways in which poverty is instrumentally experienced in urban America. We investigated the role of lived poverty at both the individual and neighborhood levels in transactional sex behavior among African American men who have sex with men (MSM) residing in urban neighborhoods. Using population-averaged models estimated by generalized estimating equation (GEE) models, we identified individual-level and neighborhood-level factors that are associated with exchanging sex for drugs and/or money. We tested the association between neighborhood and individual-level socioeconomic status and HIV risk behavior by combining area-based measures of neighborhood quality from the US Census with individual survey data from 542 low-income African American MSM. The primary outcome measure was self-reported transactional sex defined as exchanging sex for drugs or money. Individual-level covariates included high school non-completion, income, and problem drug use. Neighborhood-level covariates were high school non-completion and poverty rates. The findings suggested that educational attainment is associated with both the individual level and neighborhood level. Participants were more likely to engage in transactional sex if they did not complete high school (OR = 1.78), and similarly if their neighbors did not complete high school (OR = 7.70). These findings suggest potential leverage points for both community-level interventions and advocacy for this population, particularly related to transactional sex and education, and will aid HIV prevention efforts that seek to address the contextual constraints on individual risk behavior.

  20. Memory, scene construction, and the human hippocampus.

    Science.gov (United States)

    Kim, Soyun; Dede, Adam J O; Hopkins, Ramona O; Squire, Larry R

    2015-04-14

    We evaluated two different perspectives about the function of the human hippocampus--one that emphasizes the importance of memory and another that emphasizes the importance of spatial processing and scene construction. We gave tests of boundary extension, scene construction, and memory to patients with lesions limited to the hippocampus or large lesions of the medial temporal lobe. The patients were intact on all of the spatial tasks and impaired on all of the memory tasks. We discuss earlier studies that associated performance on these spatial tasks to hippocampal function. Our results demonstrate the importance of medial temporal lobe structures for memory and raise doubts about the idea that these structures have a prominent role in spatial cognition.

  1. The scene and the unseen: Manipulating photographs for experiments on change blindness and scene memory: Image manipulation for change blindness

    National Research Council Canada - National Science Library

    Ball, Felix; Elzemann, Anne; Busch, Niko A

    2014-01-01

    The change blindness paradigm, in which participants often fail to notice substantial changes in a scene, is a popular tool for studying scene perception, visual memory, and the link between awareness and attention...

  2. Benzodiazepine dependence among multidrug users in the club scene.

    Science.gov (United States)

    Kurtz, Steven P; Surratt, Hilary L; Levi-Minzi, Maria A; Mooss, Angela

    2011-12-01

    Benzodiazepines (BZs) are among the most frequently prescribed drugs with the potential for abuse. Young adults ages 18-29 report the highest rates of BZ misuse in the United States. The majority of club drug users are also in this age group, and BZ misuse is prevalent in the nightclub scene. BZ dependence, however, is not well documented. This paper examines BZ dependence and its correlates among multidrug users in South Florida's nightclub scene. Data were drawn from structured interviews with men and women (N=521) who reported regular attendance at large dance clubs and recent use of both club drugs and BZs. Prevalences of BZ-related problems were 7.9% for BZ dependence, 22.6% BZ abuse, and 25% BZ abuse and/or dependence. In bivariate logistic regression models, heavy cocaine use (OR 2.27; 95% CI 1.18, 4.38), severe mental distress (OR 2.63; 95% CI 1.33, 5.21), and childhood victimization history (OR 2.43; 95% CI 1.10, 5.38) were associated with BZ dependence. Heavy cocaine use (OR 2.14; 95% CI 1.10, 4.18) and severe mental distress (OR 2.16; 95% CI 1.07, 4.37) survived as predictors in the multivariate model. BZ misuse is widespread among multidrug users in the club scene, who also exhibit high levels of other health and social problems. BZ dependence appears to be more prevalent in this sample than in other populations described in the literature. Recommendations for intervention and additional research are described. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  3. Static Scene Statistical Non-Uniformity Correction

    Science.gov (United States)

    2015-03-01

    Error NUC Non-Uniformity Correction RMSE Root Mean Squared Error RSD Relative Standard Deviation S3NUC Static Scene Statistical Non-Uniformity...Deviation ( RSD ) which normalizes the standard deviation, σ, to the mean estimated value, µ using the equation RS D = σ µ × 100. The RSD plot of the gain...estimates is shown in Figure 4.1(b). The RSD plot shows that after a sample size of approximately 10, the different photocount values and the inclusion

  4. Using Ignorance in 3D Scene Understanding

    OpenAIRE

    Bogdan Harasymowicz-Boggio; Barbara Siemiątkowska

    2014-01-01

    Awareness of its own limitations is a fundamental feature of the human sight, which has been almost completely omitted in computer vision systems. In this paper we present a method of explicitly using information about perceptual limitations of a 3D vision system, such as occluded areas, limited field of view, loss of precision along with distance increase, and imperfect segmentation for a better understanding of the observed scene. The proposed mechanism integrates metric and semantic infere...

  5. Age biases in a large HIV and sexual behaviour-related internet survey among MSM.

    Science.gov (United States)

    Marcus, Ulrich; Hickson, Ford; Weatherburn, Peter; Schmidt, Axel J

    2013-09-10

    Behavioural data from MSM are usually collected in non-representative convenience samples, increasingly on the internet. Epidemiological data from such samples might be useful for comparisons between countries, but are subject to unknown participation biases. Self-reported HIV diagnoses from participants of the European MSM Internet Survey (EMIS) living in the Czech Republic, Germany, The Netherlands, Portugal, Sweden and the United Kingdom were compared with surveillance data, for both the overall diagnosed prevalence and for new diagnoses made in 2009. Country level prevalence and new diagnoses rates per 100 MSM were calculated based on an assumed MSM population size of 3% of the adult male population. Survey-surveillance discrepancies (SSD) for survey participation, diagnosed HIV prevalence and new HIV diagnoses were determined as ratios of proportions. Results are calculated and presented by 5-year age groups for MSM aged 15-64. Surveillance derived estimates of diagnosed HIV prevalence among MSM aged 15-64 ranged from 0.63% in the Czech Republic to 4.93% in The Netherlands. New HIV diagnoses rates ranged between 0.10 per 100 MSM in the Czech Republic and 0.48 per 100 in The Netherlands. Self-reported rates from EMIS were consistently higher, with prevalence ranging from 2.68% in the Czech Republic to 12.72% in The Netherlands, and new HIV diagnoses rates from 0.36 per 100 in Sweden to 1.44 per 100 in The Netherlands. Across age groups, the survey surveillance discrepancies (SSD) for new HIV diagnoses were between 1.93 in UK and 5.95 in the Czech Republic, and for diagnosed prevalence between 1.80 in Germany and 4.26 in the Czech Republic.Internet samples of MSM were skewed towards younger age groups when compared to an age distribution of the general adult male population. Survey-surveillance discrepancies (SSD) for EMIS participation were inverse u-shaped across the age range. The two HIV-related SSD were u- or j-shaped with higher values for the very young

  6. Estimating perception of scene layout properties from global image features.

    Science.gov (United States)

    Ross, Michael G; Oliva, Aude

    2010-01-08

    The relationship between image features and scene structure is central to the study of human visual perception and computer vision, but many of the specifics of real-world layout perception remain unknown. We do not know which image features are relevant to perceiving layout properties, or whether those features provide the same information for every type of image. Furthermore, we do not know the spatial resolutions required for perceiving different properties. This paper describes an experiment and a computational model that provides new insights on these issues. Humans perceive the global spatial layout properties such as dominant depth, openness, and perspective, from a single image. This work describes an algorithm that reliably predicts human layout judgments. This model's predictions are general, not specific to the observers it trained on. Analysis reveals that the optimal spatial resolutions for determining layout vary with the content of the space and the property being estimated. Openness is best estimated at high resolution, depth is best estimated at medium resolution, and perspective is best estimated at low resolution. Given the reliability and simplicity of estimating the global layout of real-world environments, this model could help resolve perceptual ambiguities encountered by more detailed scene reconstruction schemas.

  7. Enhancement of a locally developed HIV prevention intervention for Hispanic/Latino MSM: A partnership of community-based organizations, a university, and the Centers for Disease Control and Prevention

    Science.gov (United States)

    Rhodes, Scott D.; Alonzo, Jorge; Mann, Lilli; Freeman, Arin; Sun, Christina J.; Garcia, Manuel; Painter, Thomas M.

    2015-01-01

    Hispanic/Latino men who have sex with men (MSM) in the United States are disproportionately affected by HIV and other sexually transmitted diseases (STDs); however, no efficacious behavioral interventions are currently available for use with this vulnerable population. We describe the development and enhancement of HOLA en Grupos, a community-based behavioral HIV/STD prevention intervention for Spanish-speaking Hispanic/Latino MSM that is currently being implemented and evaluated. Our enhancement process included incorporating local data on risks and context; identifying community priorities; defining intervention core elements and key characteristics; developing a logic model; developing an intervention logo; enhancing intervention activities and materials; scripting intervention delivery; expanding the comparison intervention; and establishing a materials review committee. If efficacious, HOLA en Grupos will be the first behavioral intervention to be identified for potential use with Hispanic/Latino MSM, thereby contributing to the body of evidence-based resources that may be used for preventing HIV/STD infection among these MSM and their sex partners. PMID:26241382

  8. Enhancement of a Locally Developed HIV Prevention Intervention for Hispanic/Latino MSM: A Partnership of Community-Based Organizations, a University, and the Centers for Disease Control and Prevention.

    Science.gov (United States)

    Rhodes, Scott D; Alonzo, Jorge; Mann, Lilli; Freeman, Arin; Sun, Christina J; Garcia, Manuel; Painter, Thomas M

    2015-08-01

    Hispanic/Latino men who have sex with men (MSM) in the United States are disproportionately affected by HIV and other sexually transmitted diseases (STDs); however, no efficacious behavioral HIV/STD prevention interventions are currently available for use with this vulnerable population. We describe the enhancement of HOLA en Grupos, a community-based behavioral HIV/STD prevention intervention for Spanish-speaking Hispanic/Latino MSM that is currently being implemented and evaluated in North Carolina with support from the Centers of Disease Control and Prevention (CDC). Our intervention enhancement process included incorporating local data on risks and context; identifying community needs and priorities; defining intervention core elements and key characteristics; developing a logic model; developing an intervention logo; enhancing intervention activities and materials; scripting intervention delivery; expanding the comparison intervention; and establishing a materials review committee. If the CDC-sponsored evaluation determines that HOLA en Grupos is efficacious, it will be the first such behavioral HIV/STD prevention intervention to be identified for potential use with Hispanic/Latino MSM, thereby contributing to the body of evidence-based resources that may be used for preventing HIV/STD infection among these MSM and their sex partners.

  9. [Relations between self-discrimination of MSM and sexual behavior and psychological factors].

    Science.gov (United States)

    Wang, Yi; Zhang, Hong-bo; Xu, Jie; Zhang, Guang-gui; Yang, Hong-wu; Fan, Jing

    2010-07-01

    To understand the self-discrimination experience of MSM and its relationship with sexual behavior and psychological factors. By respondent-driven sampling (RDS) method, a call-for action and anonymous self-administration questionnaire investigation was carried out in Mianyang city on experience of self-discriminations, sexual partners and behaviors and depression symptom, etc. The first 12 qualified people were designated as the "root" in the whole investigation from different MSM subgroups. Every "root" would get 3 recruit cards after their own investigation, then cards could be promoted to another 3 qualified people who were willing to accept questionnaires. And this process would go on till the sample size was accomplished. χ(2) test, rank correlation and contingency coefficient would be applied for the statistical analysis. In total, 201 persons were investigated. Within the past 6 months, 59.2% (119/201) persons felt they did harm to their family or made the family down as gays, 79.6% (160/201) had to disguise their real sexual orientation in avoidance of being discriminated, 39.3% (79/201) were humiliated for having gay sex. It showed correlation between humiliation or harm to family and frequency to disco balls/night clubs (r = 0.196, χ(2) = 7.95, P discriminated and the frequency of show up in the cybercafé (r = 0.272, χ(2) = 15.932, P discrimination was connected to entrance into gay-welcome places, acceptance of HIV consultancy and tests, posting gay information among MSM friends and hold of many sexual partners. Meanwhile, the pressure was rising when depression was checked out. Self-discrimination was prevalent among MSM, which had brought critical influence on the individual behavior, MSM psychological health and prevalence of AIDS.

  10. Towards preparedness for PrEP: PrEP awareness and acceptability among MSM at high risk of HIV transmission who use sociosexual media in four Celtic nations: Scotland, Wales, Northern Ireland and The Republic of Ireland: an online survey.

    Science.gov (United States)

    Frankis, Jamie S; Young, Ingrid; Lorimer, Karen; Davis, Mark; Flowers, Paul

    2016-06-01

    To assess the awareness and acceptability of pre-exposure prophylaxis (PrEP) among men who have sex with men (MSM) and use sociosexual media at high risk of HIV infection in four Celtic nations. Cross-sectional study. Online self-complete survey of 386 HIV-negative/status unknown MSM who reported condomless anal intercourse (CAI) with ≥2 men in the last year, recruited from gay sociosexual media. One-third (34.5%, 132/386) of the participants were aware of PrEP but over half (58.5%, 226/356) reported that they would be willing to use PrEP if it were available to them. Only men who regularly tested for HIV every 6 months (adjusted OR 2.89, 95% CI 1.54 to 5.42) were more likely to be aware of PrEP. PrEP acceptability was only associated with reporting ≥5 CAI partners (OR 2.04, 95% CI 1.2 to 3.46) in the last year. Low levels of PrEP awareness were reported across these Celtic nations. Only one-third of high-risk MSM had heard of PrEP but over one-half would be willing to take a daily pill to prevent HIV infection. Sociodemographic factors, commercial gay scene proximity and social network use were unrelated to considering PrEP use. However, those reporting most CAI partners were more likely to consider PrEP use. 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/

  11. Study on general design of dual-DMD based infrared two-band scene simulation system

    Science.gov (United States)

    Pan, Yue; Qiao, Yang; Xu, Xi-ping

    2017-02-01

    Mid-wave infrared(MWIR) and long-wave infrared(LWIR) two-band scene simulation system is a kind of testing equipment that used for infrared two-band imaging seeker. Not only it would be qualified for working waveband, but also realize the essence requests that infrared radiation characteristics should correspond to the real scene. Past single-digital micromirror device (DMD) based infrared scene simulation system does not take the huge difference between targets and background radiation into account, and it cannot realize the separated modulation to two-band light beam. Consequently, single-DMD based infrared scene simulation system cannot accurately express the thermal scene model that upper-computer built, and it is not that practical. To solve the problem, we design a dual-DMD based, dual-channel, co-aperture, compact-structure infrared two-band scene simulation system. The operating principle of the system is introduced in detail, and energy transfer process of the hardware-in-the-loop simulation experiment is analyzed as well. Also, it builds the equation about the signal-to-noise ratio of infrared detector in the seeker, directing the system overall design. The general design scheme of system is given, including the creation of infrared scene model, overall control, optical-mechanical structure design and image registration. By analyzing and comparing the past designs, we discuss the arrangement of optical engine framework in the system. According to the main content of working principle and overall design, we summarize each key techniques in the system.

  12. Influence of a psychological perspective on scene viewing and memory for scenes.

    Science.gov (United States)

    Kaakinen, Johanna K; Hyönä, Jukka; Viljanen, Minna

    2011-07-01

    In the study, 33 participants viewed photographs from either a potential homebuyer's or a burglar's perspective, or in preparation for a memory test, while their eye movements were recorded. A free recall and a picture recognition task were performed after viewing. The results showed that perspective had rapid effects, in that the second fixation after the scene onset was more likely to land on perspective-relevant than on perspective-irrelevant areas within the scene. Perspective-relevant areas also attracted longer total fixation time, more visits, and longer first-pass dwell times than did perspective-irrelevant areas. As for the effects of visual saliency, the first fixation was more likely to land on a salient than on a nonsalient area; salient areas also attracted more visits and longer total fixation time than did nonsalient areas. Recall and recognition performance reflected the eye fixation results: Both were overall higher for perspective-relevant than for perspective-irrelevant scene objects. The relatively low error rates in the recognition task suggest that participants had gained an accurate memory for scene objects. The findings suggest that the role of bottom-up versus top-down factors varies as a function of viewing task and the time-course of scene processing. © 2011 The Experimental Psychology Society

  13. HIV testing among Portuguese men who have sex with men--results from the European MSM Internet Survey (EMIS).

    Science.gov (United States)

    Carvalho, C; Fuertes, R; Lucas, R; Martins, A; Campos, M J; Mendão, L; Schmidt, A J; Barros, H

    2013-10-01

    To describe HIV testing behaviour and context of MSM in Portugal participating in the European MSM Internet Survey (EMIS). Data for the Portuguese sample were extracted and those for 5187 participants were analysed. Multivariate logistic regression models were fitted to quantify the association between participants' characteristics and HIV testing behaviour and context. Seventy-two percent of the participants had ever been tested for HIV and among those ever tested, 11% were diagnosed with HIV. Primary care was the most common testing setting for HIV-negative men (37%). Compared to those never tested, men who had ever taken an HIV test had higher educational level (aOR 1.89, 95% CI 1.67-2.14) and identified themselves as gay/homosexual more frequently (aOR 1.94 , 95% CI 1.70-2.20). HIV testing odds significantly increased with the number of sexual partners in the previous 12 months. Those who reported unprotected anal intercourse (UAI) with a partner of unknown or serodiscordant HIV status in the previous 12 months were less likely to report an HIV test (aOR 0.38, 95% CI 0.33-0.44). Among those never tested or who tested negative, 41% and 22% reported UAI with a partner of unknown or serodiscordant status in the previous 12 months, respectively. Among men with diagnosed HIV, 72% were currently on antiretroviral therapy and 58% reported an undetectable viral load. More than one third (38%) of those who had detectable or unknown/undisclosed viral load reported at least one episode of UAI with a partner of unknown or serodiscordant HIV status in the last 12 months. Actual interventions should focus on: improving testing uptake and counselling; increasing treatment coverage; achieving and maintaining an undetectable viral load; and intensifying prevention efforts focused on consistent condom use. © 2013 British HIV Association.

  14. Functional neuroanatomy of auditory scene analysis in Alzheimer's disease.

    Science.gov (United States)

    Golden, Hannah L; Agustus, Jennifer L; Goll, Johanna C; Downey, Laura E; Mummery, Catherine J; Schott, Jonathan M; Crutch, Sebastian J; Warren, Jason D

    2015-01-01

    Auditory scene analysis is a demanding computational process that is performed automatically and efficiently by the healthy brain but vulnerable to the neurodegenerative pathology of Alzheimer's disease. Here we assessed the functional neuroanatomy of auditory scene analysis in Alzheimer's disease using the well-known 'cocktail party effect' as a model paradigm whereby stored templates for auditory objects (e.g., hearing one's spoken name) are used to segregate auditory 'foreground' and 'background'. Patients with typical amnestic Alzheimer's disease (n = 13) and age-matched healthy individuals (n = 17) underwent functional 3T-MRI using a sparse acquisition protocol with passive listening to auditory stimulus conditions comprising the participant's own name interleaved with or superimposed on multi-talker babble, and spectrally rotated (unrecognisable) analogues of these conditions. Name identification (conditions containing the participant's own name contrasted with spectrally rotated analogues) produced extensive bilateral activation involving superior temporal cortex in both the AD and healthy control groups, with no significant differences between groups. Auditory object segregation (conditions with interleaved name sounds contrasted with superimposed name sounds) produced activation of right posterior superior temporal cortex in both groups, again with no differences between groups. However, the cocktail party effect (interaction of own name identification with auditory object segregation processing) produced activation of right supramarginal gyrus in the AD group that was significantly enhanced compared with the healthy control group. The findings delineate an altered functional neuroanatomical profile of auditory scene analysis in Alzheimer's disease that may constitute a novel computational signature of this neurodegenerative pathology.

  15. Functional neuroanatomy of auditory scene analysis in Alzheimer's disease

    Directory of Open Access Journals (Sweden)

    Hannah L. Golden

    2015-01-01

    Full Text Available Auditory scene analysis is a demanding computational process that is performed automatically and efficiently by the healthy brain but vulnerable to the neurodegenerative pathology of Alzheimer's disease. Here we assessed the functional neuroanatomy of auditory scene analysis in Alzheimer's disease using the well-known ‘cocktail party effect’ as a model paradigm whereby stored templates for auditory objects (e.g., hearing one's spoken name are used to segregate auditory ‘foreground’ and ‘background’. Patients with typical amnestic Alzheimer's disease (n = 13 and age-matched healthy individuals (n = 17 underwent functional 3T-MRI using a sparse acquisition protocol with passive listening to auditory stimulus conditions comprising the participant's own name interleaved with or superimposed on multi-talker babble, and spectrally rotated (unrecognisable analogues of these conditions. Name identification (conditions containing the participant's own name contrasted with spectrally rotated analogues produced extensive bilateral activation involving superior temporal cortex in both the AD and healthy control groups, with no significant differences between groups. Auditory object segregation (conditions with interleaved name sounds contrasted with superimposed name sounds produced activation of right posterior superior temporal cortex in both groups, again with no differences between groups. However, the cocktail party effect (interaction of own name identification with auditory object segregation processing produced activation of right supramarginal gyrus in the AD group that was significantly enhanced compared with the healthy control group. The findings delineate an altered functional neuroanatomical profile of auditory scene analysis in Alzheimer's disease that may constitute a novel computational signature of this neurodegenerative pathology.

  16. Validation of the ASTER instrument level 1A scene geometry

    Science.gov (United States)

    Kieffer, H.H.; Mullins, K.F.; MacKinnon, D.J.

    2008-01-01

    An independent assessment of the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) instrument geometry was undertaken by the U.S. ASTER Team, to confirm the geometric correction parameters developed and applied to Level 1A (radiometrically and geometrically raw with correction parameters appended) ASTER data. The goal was to evaluate the geometric quality of the ASTER system and the stability of the Terra spacecraft. ASTER is a 15-band system containing optical instruments with resolutions from 15- to 90-meters; all geometrically registered products are ultimately tied to the 15-meter Visible and Near Infrared (VNIR) sub-system. Our evaluation process first involved establishing a large database of Ground Control Points (GCP) in the mid-western United States; an area with features of an appropriate size for spacecraft instrument resolutions. We used standard U.S. Geological Survey (USGS) Digital Orthophoto Quads (DOQS) of areas in the mid-west to locate accurate GCPs by systematically identifying road intersections and recording their coordinates. Elevations for these points were derived from USGS Digital Elevation Models (DEMS). Road intersections in a swath of nine contiguous ASTER scenes were then matched to the GCPs, including terrain correction. We found no significant distortion in the images; after a simple image offset to absolute position, the RMS residual of about 200 points per scene was less than one-half a VNIR pixel. Absolute locations were within 80 meters, with a slow drift of about 10 meters over the entire 530-kilometer swath. Using strictly simultaneous observations of scenes 370 kilometers apart, we determined a stereo angle correction of 0.00134 degree with an accuracy of one microradian. The mid-west GCP field and the techniques used here should be widely applicable in assessing other spacecraft instruments having resolutions from 5 to 50-meters. ?? 2008 American Society for Photogrammetry and Remote Sensing.

  17. Evaluation methodology for query-based scene understanding systems

    Science.gov (United States)

    Huster, Todd P.; Ross, Timothy D.; Culbertson, Jared L.

    2015-05-01

    In this paper, we are proposing a method for the principled evaluation of scene understanding systems in a query-based framework. We can think of a query-based scene understanding system as a generalization of typical sensor exploitation systems where instead of performing a narrowly defined task (e.g., detect, track, classify, etc.), the system can perform general user-defined tasks specified in a query language. Examples of this type of system have been developed as part of DARPA's Mathematics of Sensing, Exploitation, and Execution (MSEE) program. There is a body of literature on the evaluation of typical sensor exploitation systems, but the open-ended nature of the query interface introduces new aspects to the evaluation problem that have not been widely considered before. In this paper, we state the evaluation problem and propose an approach to efficiently learn about the quality of the system under test. We consider the objective of the evaluation to be to build a performance model of the system under test, and we rely on the principles of Bayesian experiment design to help construct and select optimal queries for learning about the parameters of that model.

  18. Study of magnetic field distribution in anisotropic single twin-boundary magnetic shape memory (MSM) element in actuators

    Science.gov (United States)

    Gabdullin, N.; Khan, S. H.

    2017-10-01

    Magnetic shape memory effect exhibited by certain alloys at room temperature is known for almost 20 years. The most studied MSM alloys are Ni-Mn-Ga alloys which exhibit up to 12% magnetic field-induced strain (change in shape) depending on microstructure. A multibillion cycle operation without malfunction along with their “smart” properties make them very promising for application in electromagnetic (EM) actuators and sensors. However, considerable twinning stress of MSM crystals resulting in magneto-mechanical hysteresis decreases the efficiency and output force of MSM actuators. Whereas twinning stress of conventional MSM crystals has been significantly decreased over the years, novel crystals with Type II twin boundaries (TBs) possess even lower twinning stress. Unfortunately, the microstructure of MSM crystals with very low twinning stress tends to be unstable leading to their rapid crack growth. Whilst this phenomenon has been studied experimentally, the magnetic field distribution in anisotropic single twin-boundary MSM elements has not been considered yet. This paper analyses the magnetic field distribution in two-variant single twin-boundary MSM elements and discusses its effects on magnetic field-induced stress acting on the twin boundary.

  19. Prevalence of prior HIV testing and associated factors among MSM in Zhejiang Province, China: a cross-sectional study

    Directory of Open Access Journals (Sweden)

    Runhua Li

    2016-11-01

    Full Text Available Abstract Background Men who have sex with men (MSM have become one of high-risk population for human immunodeficiency virus (HIV infection, due to their multiple sex partners and unprotected anal intercourse. Promoting HIV testing is an effective strategy for the prevention and control of HIV infection. We assessed the factors associated with a prior HIV testing history, which could provide guidance for implementation of future HIV intervention programs. Methods A cross-sectional study was conducted in three cities of Zhejiang Province, namely, Hangzhou, Ningbo and Wenzhou, using respondent-driven sampling, between December 2013 and June 2014. A face-to-face questionnaire survey was employed to collect relevant information about HIV testing. Univariate and multivariate logistic regression analyses were used to identify the factors associated with a prior HIV testing history. Results The adjusted rate of prior HIV testing among MSM in Zhejiang Province was 55.9 %. The adjusted rates of HIV and syphilis infections among MSM in Zhejiang Province were 14.0 % and 11.4 %, respectively. A weighted multivariate analysis showed that MSM of older age were more likely to be tested, as were MSM with higher level of education, self-reported homosexuality and a higher frequency of receiving AIDS/sexually transmitted infections educational intervention in the past year. MSM with suicidal inclination and self-perceived lower possibility of HIV infection were less likely to report ever having undergone an HIV test. Conclusions The prevalence of prior HIV testing among MSM in Zhejiang Province, China is low. Effective and more frequent interventional measures should be adopted to improve risk awareness and psychosocial support for younger, less educated MSM, and to encourage more MSM to undergo HIV testing.

  20. Scene Recognition for Indoor Localization Using a Multi-Sensor Fusion Approach.

    Science.gov (United States)

    Liu, Mengyun; Chen, Ruizhi; Li, Deren; Chen, Yujin; Guo, Guangyi; Cao, Zhipeng; Pan, Yuanjin

    2017-12-08

    After decades of research, there is still no solution for indoor localization like the GNSS (Global Navigation Satellite System) solution for outdoor environments. The major reasons for this phenomenon are the complex spatial topology and RF transmission environment. To deal with these problems, an indoor scene constrained method for localization is proposed in this paper, which is inspired by the visual cognition ability of the human brain and the progress in the computer vision field regarding high-level image understanding. Furthermore, a multi-sensor fusion method is implemented on a commercial smartphone including cameras, WiFi and inertial sensors. Compared to former research, the camera on a smartphone is used to "see" which scene the user is in. With this information, a particle filter algorithm constrained by scene information is adopted to determine the final location. For indoor scene recognition, we take advantage of deep learning that has been proven to be highly effective in the computer vision community. For particle filter, both WiFi and magnetic field signals are used to update the weights of particles. Similar to other fingerprinting localization methods, there are two stages in the proposed system, offline training and online localization. In the offline stage, an indoor scene model is trained by Caffe (one of the most popular open source frameworks for deep learning) and a fingerprint database is constructed by user trajectories in different scenes. To reduce the volume requirement of training data for deep learning, a fine-tuned method is adopted for model training. In the online stage, a camera in a smartphone is used to recognize the initial scene. Then a particle filter algorithm is used to fuse the sensor data and determine the final location. To prove the effectiveness of the proposed method, an Android client and a web server are implemented. The Android client is used to collect data and locate a user. The web server is developed for

  1. Scene Recognition for Indoor Localization Using a Multi-Sensor Fusion Approach

    Directory of Open Access Journals (Sweden)

    Mengyun Liu

    2017-12-01

    Full Text Available After decades of research, there is still no solution for indoor localization like the GNSS (Global Navigation Satellite System solution for outdoor environments. The major reasons for this phenomenon are the complex spatial topology and RF transmission environment. To deal with these problems, an indoor scene constrained method for localization is proposed in this paper, which is inspired by the visual cognition ability of the human brain and the progress in the computer vision field regarding high-level image understanding. Furthermore, a multi-sensor fusion method is implemented on a commercial smartphone including cameras, WiFi and inertial sensors. Compared to former research, the camera on a smartphone is used to “see” which scene the user is in. With this information, a particle filter algorithm constrained by scene information is adopted to determine the final location. For indoor scene recognition, we take advantage of deep learning that has been proven to be highly effective in the computer vision community. For particle filter, both WiFi and magnetic field signals are used to update the weights of particles. Similar to other fingerprinting localization methods, there are two stages in the proposed system, offline training and online localization. In the offline stage, an indoor scene model is trained by Caffe (one of the most popular open source frameworks for deep learning and a fingerprint database is constructed by user trajectories in different scenes. To reduce the volume requirement of training data for deep learning, a fine-tuned method is adopted for model training. In the online stage, a camera in a smartphone is used to recognize the initial scene. Then a particle filter algorithm is used to fuse the sensor data and determine the final location. To prove the effectiveness of the proposed method, an Android client and a web server are implemented. The Android client is used to collect data and locate a user. The web

  2. Review of On-Scene Management of Mass-Casualty Attacks

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    Annelie Holgersson

    2016-02-01

    Full Text Available Background: The scene of a mass-casualty attack (MCA entails a crime scene, a hazardous space, and a great number of people needing medical assistance. Public transportation has been the target of such attacks and involves a high probability of generating mass casualties. The review aimed to investigate challenges for on-scene responses to MCAs and suggestions made to counter these challenges, with special attention given to attacks on public transportation and associated terminals. Methods: Articles were found through PubMed and Scopus, “relevant articles” as defined by the databases, and a manual search of references. Inclusion criteria were that the article referred to attack(s and/or a public transportation-related incident and issues concerning formal on-scene response. An appraisal of the articles’ scientific quality was conducted based on an evidence hierarchy model developed for the study. Results: One hundred and five articles were reviewed. Challenges for command and coordination on scene included establishing leadership, inter-agency collaboration, multiple incident sites, and logistics. Safety issues entailed knowledge and use of personal protective equipment, risk awareness and expectations, cordons, dynamic risk assessment, defensive versus offensive approaches, and joining forces. Communication concerns were equipment shortfalls, dialoguing, and providing information. Assessment problems were scene layout and interpreting environmental indicators as well as understanding setting-driven needs for specialist skills and resources. Triage and treatment difficulties included differing triage systems, directing casualties, uncommon injuries, field hospitals, level of care, providing psychological and pediatric care. Transportation hardships included scene access, distance to hospitals, and distribution of casualties. Conclusion: Commonly encountered challenges during unintentional incidents were added to during MCAs, implying

  3. Diffraction analysis for DMD-based scene projectors in the long-wave infrared.

    Science.gov (United States)

    Han, Qing; Zhang, Jianzhong; Wang, Jian; Sun, Qiang

    2016-10-01

    Diffraction effects play a significant role in the digital micromirror device (DMD)-based scene projectors in the long-wave infrared (IR) band (8-12 μm). The contrast provided by these projector systems can become noticeably worse because of the diffraction characteristics of the DMD. We apply a diffraction grating model of the DMD based on the scalar diffraction theory and the Fourier transform to address this issue. In addition, a simulation calculation is conducted with MATLAB. Finally, the simulation result is verified with an experiment. The simulation and experimental results indicate that, when the incident azimuth angle is 0° and the zenith angle is between 42°and 46°, the scene projectors will have a good imaging contrast in the long-wave IR. The diffraction grating model proposed in this study provides a method to improve the contrast of DMD-based scene projectors in the long-wave IR.

  4. High Prevalence and Genotype Diversity of Anal HPV Infection among MSM in Northern Thailand.

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    Taweewat Supindham

    Full Text Available HPV infection is common and may cause cancer among men who have sex with men (MSM. Anal HPV infection (HPV+ was found in 85% of HIV-positive (HIV+ and 59% of HIV-negative (HIV- MSM in Bangkok, central Thailand. As little is known about HPV in this group in northern Thailand, we studied MSM subgroups comprised of gay men (GM, bisexual men (BM, and transgender women (TGW.From July 2012 through January 2013, 85 (42.5% of 200 GM, 30 (15% BM, and 85 (42.5% TGW who practiced receptive anal intercourse were recruited after informed consent, followed by self-assisted computer interview, HIV testing, and anal swabs for HPV genotyping.Of 197 adequate specimens, the overall prevalence of any HPV was 157 (80%. Prevalence was 89% (76/85 in GM, 48% (14/29 in BM, and 81% (67/83 in TGW. The most common high-risk types were HPV16 (27% of 197, HPV58 (23%, and HPV51 (18%. Prevalence of high-risk types was 74% in 85 GM, 35% in 29 BM, and 71% in 83 TGW. Prevalence of any HPV type, or high-risk type, was 100% and 94%, respectively, among 48 HIV+ MSM, 70% and 54% among 120 HIV- MSM. Of the 197 specimens, 36% (70 had HPV types 16 and/or 18 in the bivalent vaccine, compared to 48% (95 with ≥1 of types 16/18/06/11 in the quadrivalent, 56% (111 for 16/18/31/33/45/52/58 in the 7-valent, and 64% (126 for 16/18/31/33/45/52/58/06/11 in the 9-valent. HIV+, GM, and TGW were independently associated with HPV infection.We found higher rates of both any HPV and high-risk types than previous studies. Among the heretofore unstudied TGW, their equivalent HPV rates were comparable to GM. Current and investigational HPV vaccines could substantially protect GM, BM, and TGW from the serious consequences of HPV infection especially among HIV + MSM.

  5. Risk factors for anal HSIL in HIV-positive MSM: is targeted screening possible?

    Science.gov (United States)

    van Heukelom, Matthijs L Siegenbeek; Marra, Elske; de Vries, Henry J C; van der Loeff, Maarten F Schim; Prins, Jan M

    2017-09-18

    HIV-positive men-who-have-sex-with-men (MSM) are at increased risk for developing anal squamous cell carcinoma (aSCC). Detection of precursor lesions of anal cancer (anal high-grade squamous intraepithelial lesions; HSIL) is cumbersome and expensive. Our objective was to identify potential risk factors for anal HSIL in HIV-positive MSM to develop more stringent screening criteria. We studied a cohort of MSM screened by high-resolution anoscopy (HRA) at three HIV clinics in Amsterdam, the Netherlands. For every first HRA performed in a patient we analyzed five demographic- and seven HIV-related potential risk factors for 4 different outcome measures: histologically proven anal HSIL vs. no SIL, HSIL-AIN2 vs. no SIL, HSIL-AIN3 vs. no SIL and HSIL vs. no HSIL. We used univariable and multi-level, multivariable logistic regression. From 2008 through 2015, 497 out of 1678 (30%) screened HIV-positive MSM had anal HSIL. The mean age was 49 years (SD 9.6), 96% used cART, median duration of cART use was 7.8 years (IQR 4.0-12.4). Increasing age (aOR 0.82, 95% CI 0.70-0.94, P=0.006) and years living with suppressed viral load (1 to 5 years suppressed aOR 0.52 [95% CI 0.34-0.80], 5.01 to 10 years aOR 0.47 [95% CI 0.29-0.74], >10 years aOR 0.54 [0.34-0.87], all compared to < 1 year suppressed, P = 0.009) were found to be protective for HSIL vs. no SIL. Young HIV-positive MSM without viral suppression are statistically at highest risk for anal HSIL, but given the high prevalence among all virally suppressed men, we advise that all HIV-positive MSM should be screened for HSIL.

  6. TMS to object cortex affects both object and scene remote networks while TMS to scene cortex only affects scene networks.

    Science.gov (United States)

    Rafique, Sara A; Solomon-Harris, Lily M; Steeves, Jennifer K E

    2015-12-01

    Viewing the world involves many computations across a great number of regions of the brain, all the while appearing seamless and effortless. We sought to determine the connectivity of object and scene processing regions of cortex through the influence of transient focal neural noise in discrete nodes within these networks. We consecutively paired repetitive transcranial magnetic stimulation (rTMS) with functional magnetic resonance-adaptation (fMR-A) to measure the effect of rTMS on functional response properties at the stimulation site and in remote regions. In separate sessions, rTMS was applied to the object preferential lateral occipital region (LO) and scene preferential transverse occipital sulcus (TOS). Pre- and post-stimulation responses were compared using fMR-A. In addition to modulating BOLD signal at the stimulation site, TMS affected remote regions revealing inter and intrahemispheric connections between LO, TOS, and the posterior parahippocampal place area (PPA). Moreover, we show remote effects from object preferential LO to outside the ventral perception network, in parietal and frontal areas, indicating an interaction of dorsal and ventral streams and possibly a shared common framework of perception and action. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. Performativity and Genesis of the Scene

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    Sílvia Fernandes

    2013-07-01

    Full Text Available From the recognition of the tension between reality and fiction in contemporary theatre, generally defined as theatre of the real, we intend to make an intersection of this phenomenon with the theoretical field of performativity, which focuses on the work in process, dynamic transformation and experience. The intention is to associate the theory of performativity to observations about the latest work of Theatre Vertigo, directed by Antonio Araujo, Bom Retiro 958 metros. The use of genetic ways to approach theatre will serve as a motto to interpret some aspects of the creative process and the scene.

  8. Image policy, subjectivation and argument scenes

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    Ângela Cristina Salgueiro Marques

    2014-12-01

    Full Text Available This paper is aimed at discussing, with focus on Jacques Rancière, how an image policy can be noticed in the creative production of scenes of dissent from which the political agent emerge, appears and constitute himself in a process of subjectivation. The political and critical power of the image is linked to survival acts: operations and attempts that enable to resist to captures, silences and excesses comitted by the media discourses, by the social institutions and by the State.

  9. The gay bashing scene chez Proust.

    Science.gov (United States)

    Campbell, T

    1993-01-01

    This essay presents a contemporary translation of and brief commentary on the gay bashing scene found in Marcel Proust's A la Recherche du Temps perdu: Le Côté de Guermantes, Tome I. The paper notes that Proust argues in this passage for the acceptance of homosexuality for two main reasons: because gay bashing won't eradicate it; and because gayness is the simple, direct movement of a being toward perceived beauty. The paper suggests that Proust reveals his own gayness (and that of his protagonist) by employing the latter argument in defense of homosexuality whereas, throughout the novel, he presents heterosexual attraction as an immensely indirect, artistically manufactured construct.

  10. HDR IMAGING FOR FEATURE DETECTION ON DETAILED ARCHITECTURAL SCENES

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    G. Kontogianni

    2015-02-01

    Full Text Available 3D reconstruction relies on accurate detection, extraction, description and matching of image features. This is even truer for complex architectural scenes that pose needs for 3D models of high quality, without any loss of detail in geometry or color. Illumination conditions influence the radiometric quality of images, as standard sensors cannot depict properly a wide range of intensities in the same scene. Indeed, overexposed or underexposed pixels cause irreplaceable information loss and degrade digital representation. Images taken under extreme lighting environments may be thus prohibitive for feature detection/extraction and consequently for matching and 3D reconstruction. High Dynamic Range (HDR images could be helpful for these operators because they broaden the limits of illumination range that Standard or Low Dynamic Range (SDR/LDR images can capture and increase in this way the amount of details contained in the image. Experimental results of this study prove this assumption as they examine state of the art feature detectors applied both on standard dynamic range and HDR images.

  11. Scene construction in developmental amnesia: An fMRI study☆

    Science.gov (United States)

    Mullally, Sinéad L.; Vargha-Khadem, Faraneh; Maguire, Eleanor A.

    2014-01-01

    Amnesic patients with bilateral hippocampal damage sustained in adulthood are generally unable to construct scenes in their imagination. By contrast, patients with developmental amnesia (DA), where hippocampal damage was acquired early in life, have preserved performance on this task, although the reason for this sparing is unclear. One possibility is that residual function in remnant hippocampal tissue is sufficient to support basic scene construction in DA. Such a situation was found in the one amnesic patient with adult-acquired hippocampal damage (P01) who could also construct scenes. Alternatively, DA patients’ scene construction might not depend on the hippocampus, perhaps being instead reliant on non-hippocampal regions and mediated by semantic knowledge. To adjudicate between these two possibilities, we examined scene construction during functional MRI (fMRI) in Jon, a well-characterised patient with DA who has previously been shown to have preserved scene construction. We found that when Jon constructed scenes he activated many of the regions known to be associated with imagining scenes in control participants including ventromedial prefrontal cortex, posterior cingulate, retrosplenial and posterior parietal cortices. Critically, however, activity was not increased in Jon's remnant hippocampal tissue. Direct comparisons with a group of control participants and patient P01, confirmed that they activated their right hippocampus more than Jon. Our results show that a type of non-hippocampal dependent scene construction is possible and occurs in DA, perhaps mediated by semantic memory, which does not appear to involve the vivid visualisation of imagined scenes. PMID:24231038

  12. Semantic guidance of eye movements in real-world scenes.

    Science.gov (United States)

    Hwang, Alex D; Wang, Hsueh-Cheng; Pomplun, Marc

    2011-05-25

    The perception of objects in our visual world is influenced by not only their low-level visual features such as shape and color, but also their high-level features such as meaning and semantic relations among them. While it has been shown that low-level features in real-world scenes guide eye movements during scene inspection and search, the influence of semantic similarity among scene objects on eye movements in such situations has not been investigated. Here we study guidance of eye movements by semantic similarity among objects during real-world scene inspection and search. By selecting scenes from the LabelMe object-annotated image database and applying latent semantic analysis (LSA) to the object labels, we generated semantic saliency maps of real-world scenes based on the semantic similarity of scene objects to the currently fixated object or the search target. An ROC analysis of these maps as predictors of subjects' gaze transitions between objects during scene inspection revealed a preference for transitions to objects that were semantically similar to the currently inspected one. Furthermore, during the course of a scene search, subjects' eye movements were progressively guided toward objects that were semantically similar to the search target. These findings demonstrate substantial semantic guidance of eye movements in real-world scenes and show its importance for understanding real-world attentional control. Copyright © 2011 Elsevier Ltd. All rights reserved.

  13. Friends, Sisters, and Wives: Social Support and Social Risks in Peer Relationships Among Men Who Have Sex With Men (MSM) in India.

    Science.gov (United States)

    Tomori, Cecilia; Srikrishnan, Aylur K; Ridgeway, Kathleen; Solomon, Sunil S; Mehta, Shruti H; Solomon, Suniti; Celentano, David D

    2016-04-01

    Globally, men who have sex with men (MSM) are at high risk for HIV. Many HIV-prevention efforts rely on community outreach and mobilization to engage MSM. This study examines peer relationships and their potential role in HIV prevention through 31 focus group discussions (FGDS) and 121 in-depth interviews (IDIs) with 363 MSM across 15 sites in India. Results indicate that MSM receive social support in friendships, sex-worker collaborations, constructed kin relationships, and romantic partnerships. Access to these relationships, however, is uneven across MSM, and can carry risks of disclosure of same-sex behavior and exclusion based on HIV- positive status. Positive peer relationships can serve as the basis of community empowerment, education, and couple-based interventions for MSM, and peer counselors can also provide a buffer against the social risks of peer relationships and facilitate linkage to care and continued engagement in treatment. These insights can improve HIV interventions for MSM in India and elsewhere.

  14. Manipulating the content of dynamic natural scenes to characterize response in human MT/MST.

    Science.gov (United States)

    Durant, Szonya; Wall, Matthew B; Zanker, Johannes M

    2011-09-09

    Optic flow is one of the most important sources of information for enabling human navigation through the world. A striking finding from single-cell studies in monkeys is the rapid saturation of response of MT/MST areas with the density of optic flow type motion information. These results are reflected psychophysically in human perception in the saturation of motion aftereffects. We began by comparing responses to natural optic flow scenes in human visual brain areas to responses to the same scenes with inverted contrast (photo negative). This changes scene familiarity while preserving local motion signals. This manipulation had no effect; however, the response was only correlated with the density of local motion (calculated by a motion correlation model) in V1, not in MT/MST. To further investigate this, we manipulated the visible proportion of natural dynamic scenes and found that areas MT and MST did not increase in response over a 16-fold increase in the amount of information presented, i.e., response had saturated. This makes sense in light of the sparseness of motion information in natural scenes, suggesting that the human brain is well adapted to exploit a small amount of dynamic signal and extract information important for survival.

  15. The green shoots of a novel training programme: progress and identified key actions to providing services to MSM at Kenyan health facilities

    Directory of Open Access Journals (Sweden)

    Elise M van der Elst

    2015-10-01

    Full Text Available Introduction: Although men who have sex with men (MSM in sub-Saharan Africa are at high risk for HIV acquisition, access to and quality of health and HIV services within this population are negatively affected by stigma and capacity within the health sector. A recently developed online MSM training programme (www.marps-africa.org was shown to contribute to reductions in MSM prejudice among healthcare providers (HCPs in coastal Kenya. In this study, we used qualitative methods to explore the provision of MSM healthcare services two years post-training in coastal Kenya. Methods: From February to July 2014, we held 10 focus group discussions (FGD with 63 participants, including HCP from 25 facilities, county AIDS coordinators and MSM from local support groups. Participants discussed availability, acceptability and accessibility of HIV healthcare for MSM. HCP also discussed changes in their health service practices after completing the training. FGD were recorded, transcribed verbatim and analyzed using Ritchie and Spencer's “framework approach” for qualitative data. Results: HCPs described continued improvements in their ability to provide service in a non-stigmatizing way to MSM patients since completing the training programme and expressed comfort engaging MSM patients in care. Four additional recommendations for improving MSM healthcare services were identified: 1 expanding the reach of MSM sensitivity training across the medical education continuum; 2 establishing guidelines to manage sexually transmitted anal infections; 3 promoting legal and policy reforms to support integration of MSM-appropriate services into healthcare; and 4 including MSM information in national reporting tools for HIV services. Conclusions: Positive impacts of this sensitivity and skills training programme were reflected in HCP attitudes two years post-intervention. Scaling-up of efforts will rely on continued policies to include MSM in healthcare programmes to

  16. Integration and segregation in auditory scene analysis

    Science.gov (United States)

    Sussman, Elyse S.

    2005-03-01

    Assessment of the neural correlates of auditory scene analysis, using an index of sound change detection that does not require the listener to attend to the sounds [a component of event-related brain potentials called the mismatch negativity (MMN)], has previously demonstrated that segregation processes can occur without attention focused on the sounds and that within-stream contextual factors influence how sound elements are integrated and represented in auditory memory. The current study investigated the relationship between the segregation and integration processes when they were called upon to function together. The pattern of MMN results showed that the integration of sound elements within a sound stream occurred after the segregation of sounds into independent streams and, further, that the individual streams were subject to contextual effects. These results are consistent with a view of auditory processing that suggests that the auditory scene is rapidly organized into distinct streams and the integration of sequential elements to perceptual units takes place on the already formed streams. This would allow for the flexibility required to identify changing within-stream sound patterns, needed to appreciate music or comprehend speech..

  17. Recognition and Memory for Briefly Presented Scenes

    Science.gov (United States)

    Potter, Mary C.

    2012-01-01

    Three times per second, our eyes make a new fixation that generates a new bottom-up analysis in the visual system. How much is extracted from each glimpse? For how long and in what form is that information remembered? To answer these questions, investigators have mimicked the effect of continual shifts of fixation by using rapid serial visual presentation of sequences of unrelated pictures. Experiments in which viewers detect specified target pictures show that detection on the basis of meaning is possible at presentation durations as brief as 13 ms, suggesting that understanding may be based on feedforward processing, without feedback. In contrast, memory for what was just seen is poor unless the viewer has about 500 ms to think about the scene: the scene does not need to remain in view. Initial memory loss after brief presentations occurs over several seconds, suggesting that at least some of the information from the previous few fixations persists long enough to support a coherent representation of the current environment. In contrast to marked memory loss shortly after brief presentations, memory for pictures viewed for 1 s or more is excellent. Although some specific visual information persists, the form and content of the perceptual and memory representations of pictures over time indicate that conceptual information is extracted early and determines most of what remains in longer-term memory. PMID:22371707

  18. Inferring mass in complex scenes by mental simulation.

    Science.gov (United States)

    Hamrick, Jessica B; Battaglia, Peter W; Griffiths, Thomas L; Tenenbaum, Joshua B

    2016-12-01

    After observing a collision between two boxes, you can immediately tell which is empty and which is full of books based on how the boxes moved. People form rich perceptions about the physical properties of objects from their interactions, an ability that plays a crucial role in learning about the physical world through our experiences. Here, we present three experiments that demonstrate people's capacity to reason about the relative masses of objects in naturalistic 3D scenes. We find that people make accurate inferences, and that they continue to fine-tune their beliefs over time. To explain our results, we propose a cognitive model that combines Bayesian inference with approximate knowledge of Newtonian physics by estimating probabilities from noisy physical simulations. We find that this model accurately predicts judgments from our experiments, suggesting that the same simulation mechanism underlies both peoples' predictions and inferences about the physical world around them. Copyright © 2016 Elsevier B.V. All rights reserved.

  19. Determinants of condom use with occasional partners among MSM in Ukraine

    Directory of Open Access Journals (Sweden)

    Nadiya Klymenko

    2012-05-01

    Full Text Available BACKGROUND: Men who have sex with men (MSM are considered a high-risk group for HIV. As condom use prevents HIV transmission, a study of factors associated with condom use with occasional partners (CUWOP among MSM was undertaken.METHODS: Case-control study with 866 participants was nested in a cross-sectional survey among MSM conducted in 2007. Controls were those who used a condom during the most recent sexual contact with an occasional partner, and cases – those who did not. Independent variables included socio-demographic characteristics, other risky behaviors, HIV knowledge and sources of information. Bivariate analysis used chi-square test and multivariate – binary logistic regression.RESULTS: Better knowledge and use of harm reduction services (HRS was associated with safer behaviors. Those respondents, who were unaware whether HIV testing was available to them, had a greater risk of unprotected sex: OR = 2.344 (95%CI 1.09-5.00 as well as those who were unclear about the quality of condoms they get from HRS. Among those not covered by HRS, older MSM and those who have multiple commercial partners are at higher risk of unprotected sex. Among those attending HRS, a major barrier to use condoms is their perception as diminishing sensitivity: OR=4.143 (95%CI 1.305-13.152. The dose-dependent association was found with frequency of alcohol consumption – unsafe sexual contacts were more likely in daily alcohol users compared to those who used alcohol on a monthly basis: OR=2.264 (95%CI 1.041-4.923. DISCUSSION: Low CUWOP is typical for those MSMs who practice other risky behaviors including frequent alcohol use, contacts with multiple commercial sex partners and non-use of HRS which include provision of information, condoms and testing. Thus HIV prevention depends not only on the fact whether preventive services are provided but whether they are used by the target group.

  20. Sexual behaviour reported by a sample of Italian MSM before and after HIV diagnosis

    Directory of Open Access Journals (Sweden)

    Laura Camoni

    2011-01-01

    Full Text Available In 2006 we conducted a cross-sectional study involving hospital clinical centres in five Italian cities to compare the sexual behaviour of HIV-positive MSM (men who have sex with men before and after the diagnosis of HIV infection. Each centre was asked to enrol 30 HIV-positive persons aged > 18 years. The questionnaire was administered to 143 MSM on average 9 years after HIV diagnosis. After diagnosis there was a decrease in the number of sexual partners: the percentage of persons who reported having had more than 2 partners decreased from 95.8% before diagnosis to 76.2% after diagnosis. After diagnosis, there was a significant decrease in the percentage of persons who had never (or not always used a condom with their stable partner for anal sex from 69.2% before diagnosis to 26.6% after diagnosis and for oral-genital sex from 74.8% before diagnosis to 51.7% after diagnosis. Though at-risk behaviour seems to decrease after diagnosis, seropositive MSM continue to engage in at-risk practices: one fourth of them did not use a condom during sexually transmitted infections (STI episodes, 12.5% of the participants had had sex for money, and 8.4% had paid for sex. The study shows that our sample of Italian HIV-positive MSM, though aware of being infected, engage in sexual behaviours that could sustain transmission of HIV and other STIs. The results could constitute the first step in implementing national prevention programs for persons living with HIV.

  1. Screening for precancerous anal lesions with P16/Ki67 immunostaining in HIV-infected MSM.

    Directory of Open Access Journals (Sweden)

    Sergio Serrano-Villar

    Full Text Available Screening of anal cancer in HIV-infected MSM with anal cytology results in high rates of false positive results and elevated burden of high-resolution anoscopies. High-risk HPV up-regulates p16 and Ki67 expression in epithelial cells. We assessed the usefulness of P16/Ki-67 immunostaining cytology for the diagnosis of precancerous anal lesions.Cross-sectional multicenter study. Concomitant anal liquid cytology with p16/Ki-67 immunostaining and HRA with biopsy of acetowhite lugol-negative lesions was performed in HIV-infected MSM. We compared the diagnostic performance of an abnormal anal cytology and p16/Ki-67 immunostaining relative to HRA-guided biopsy by logistic regression and comparison of ROC areas.We included 328 HIV-infected MSM. HSIL was histologically diagnosed in 72 subjects (25.1%, and 2 (0.6% were diagnosed with anal cancer. An abnormal cytology showed a sensitivity of 95.6% and a specificity of 58.8% for the diagnosis of biopsy-proven HSIL. P16/Ki67 positivity was associated with the presence of biopsy-proven HSIL (P trend = 0.004 but with low sensitivity (41.2% and specificity (71%. The combination of standard cytology with P16/Ki67 immunostaining did not increment the predictive value of standard cytology alone (AUC 0.685 vs. 0.673, respectively, P = 0.688.In HIV-infected MSM P16/Ki67 immunostaining does not improve the diagnostic accuracy of anal cytology, which shows a high sensitivity yet poor specificity. Other approaches aimed at improving the diagnostic accuracy of current techniques for the diagnostic of precancerous HSIL are warranted.

  2. Risk Factors Associated With HIV Among Men Who Have Sex With Men (MSM) in Ecuador.

    Science.gov (United States)

    Hernandez, Isabel; Reina-Ortiz, Miguel; Johnson, Ayesha; Rosas, Carlos; Sharma, Vinita; Teran, Santiago; Naik, Eknath; Salihu, Hamisu M; Teran, Enrique; Izurieta, Ricardo

    2017-09-01

    The Joint United Nations Program on HIV/AIDS estimates that between 0.3% and 0.7% of adults aged 15 to 49 years were living with HIV in Ecuador in 2013. However, very little is known about the HIV prevalence rate among men who have sex with men (MSM) in that country. A cross-sectional survey was conducted to investigate the knowledge, attitudes, and practices regarding HIV/AIDS as well as to estimate the prevalence of HIV among MSM in one of the cities with high HIV prevalence rates in Ecuador. In this study, questionnaires were administered to 307 adult MSM. An HIV prevalence of 10% was observed. Knowledge about HIV was high; 91% of participants could identify how HIV is transmitted. Although consistent condom use for anal sex was relatively high (89%) among participants who reported having pay-for-service clients, only 64% reported using a condom during oral sex with a client. Participants who had multiple male sexual partners (i.e., their stable male partners plus other partner[s]) had 3.7 times higher odds of testing positive for HIV compared with those who did not. They also had reduced odds of condom use. Participants who were forced to have anal receptive sex had 3 times higher odds of testing positive for HIV. Despite the finding that participants exhibited high knowledge about HIV/AIDS, a high prevalence rate of HIV was observed, which warrants targeted behavioral interventions. These data are consistent with MSM being one of the highest at-risk population groups for HIV in this region of Ecuador.

  3. A Systematic Review of Behavioral Interventions to Reduce Condomless Sex and Increase HIV Testing for Latino MSM.

    Science.gov (United States)

    Pérez, Ashley; Santamaria, E Karina; Operario, Don

    2017-12-15

    Latino men who have sex with men (MSM) in the United States are disproportionately affected by HIV, and there have been calls to improve availability of culturally sensitive HIV prevention programs for this population. This article provides a systematic review of intervention programs to reduce condomless sex and/or increase HIV testing among Latino MSM. We searched four electronic databases using a systematic review protocol, screened 1777 unique records, and identified ten interventions analyzing data from 2871 Latino MSM. Four studies reported reductions in condomless anal intercourse, and one reported reductions in number of sexual partners. All studies incorporated surface structure cultural features such as bilingual study recruitment, but the incorporation of deep structure cultural features, such as machismo and sexual silence, was lacking. There is a need for rigorously designed interventions that incorporate deep structure cultural features in order to reduce HIV among Latino MSM.

  4. MsmK, an ATPase, Contributes to Utilization of Multiple Carbohydrates and Host Colonization of Streptococcus suis.

    Science.gov (United States)

    Tan, Mei-Fang; Gao, Ting; Liu, Wan-Quan; Zhang, Chun-Yan; Yang, Xi; Zhu, Jia-Wen; Teng, Mu-Ye; Li, Lu; Zhou, Rui

    2015-01-01

    Acquisition and metabolism of carbohydrates are essential for host colonization and pathogenesis of bacterial pathogens. Different bacteria can uptake different lines of carbohydrates via ABC transporters, in which ATPase subunits energize the transport though ATP hydrolysis. Some ABC transporters possess their own ATPases, while some share a common ATPase. Here we identified MsmK, an ATPase from Streptococcus suis, an emerging zoonotic bacterium causing dead infections in pigs and humans. Genetic and biochemistry studies revealed that the MsmK was responsible for the utilization of raffinose, melibiose, maltotetraose, glycogen and maltotriose. In infected mice, the msmK-deletion mutant showed significant defects of survival and colonization when compared with its parental and complementary strains. Taken together, MsmK is an ATPase that contributes to multiple carbohydrates utilization and host colonization of S. suis. This study gives new insight into our understanding of the carbohydrates utilization and its relationship to the pathogenesis of this zoonotic pathogen.

  5. The scene and the unseen: manipulating photographs for experiments on change blindness and scene memory: image manipulation for change blindness.

    Science.gov (United States)

    Ball, Felix; Elzemann, Anne; Busch, Niko A

    2014-09-01

    The change blindness paradigm, in which participants often fail to notice substantial changes in a scene, is a popular tool for studying scene perception, visual memory, and the link between awareness and attention. Some of the most striking and popular examples of change blindness have been demonstrated with digital photographs of natural scenes; in most studies, however, much simpler displays, such as abstract stimuli or "free-floating" objects, are typically used. Although simple displays have undeniable advantages, natural scenes remain a very useful and attractive stimulus for change blindness research. To assist researchers interested in using natural-scene stimuli in change blindness experiments, we provide here a step-by-step tutorial on how to produce changes in natural-scene images with a freely available image-processing tool (GIMP). We explain how changes in a scene can be made by deleting objects or relocating them within the scene or by changing the color of an object, in just a few simple steps. We also explain how the physical properties of such changes can be analyzed using GIMP and MATLAB (a high-level scientific programming tool). Finally, we present an experiment confirming that scenes manipulated according to our guidelines are effective in inducing change blindness and demonstrating the relationship between change blindness and the physical properties of the change and inter-individual differences in performance measures. We expect that this tutorial will be useful for researchers interested in studying the mechanisms of change blindness, attention, or visual memory using natural scenes.

  6. Error Detection, Factorization and Correction for Multi-View Scene Reconstruction from Aerial Imagery

    Energy Technology Data Exchange (ETDEWEB)

    Hess-Flores, Mauricio [Univ. of California, Davis, CA (United States)

    2011-11-10

    reconstruction pre-processing, where an algorithm detects and discards frames that would lead to inaccurate feature matching, camera pose estimation degeneracies or mathematical instability in structure computation based on a residual error comparison between two different match motion models. The presented algorithms were designed for aerial video but have been proven to work across different scene types and camera motions, and for both real and synthetic scenes.

  7. Generation of Variations on Theme Music Based on Impressions of Story Scenes Considering Human's Feeling of Music and Stories

    Directory of Open Access Journals (Sweden)

    Kenkichi Ishizuka

    2008-01-01

    Full Text Available This paper describes a system which generates variations on theme music fitting to story scenes represented by texts and/or pictures. Inputs to the present system are original theme music and numerical information on given story scenes. The present system varies melodies, tempos, tones, tonalities, and accompaniments of given theme music based on impressions of story scenes. Genetic algorithms (GAs using modular neural network (MNN models as fitness functions are applied to music generation in order to reflect user's feeling of music and stories. The present system adjusts MNN models for each user on line. This paper also describes the evaluation experiments to confirm whether the generated variations on theme music reflect impressions of story scenes appropriately or not.

  8. The Role of Binocular Disparity in Rapid Scene and Pattern Recognition

    Directory of Open Access Journals (Sweden)

    Matteo Valsecchi

    2013-04-01

    Full Text Available We investigated the contribution of binocular disparity to the rapid recognition of scenes and simpler spatial patterns using a paradigm combining backward masked stimulus presentation and short-term match-to-sample recognition. First, we showed that binocular disparity did not contribute significantly to the recognition of briefly presented natural and artificial scenes, even when the availability of monocular cues was reduced. Subsequently, using dense random dot stereograms as stimuli, we showed that observers were in principle able to extract spatial patterns defined only by disparity under brief, masked presentations. Comparing our results with the predictions from a cue-summation model, we showed that combining disparity with luminance did not per se disrupt the processing of disparity. Our results suggest that the rapid recognition of scenes is mediated mostly by a monocular comparison of the images, although we can rely on stereo in fast pattern recognition.

  9. Acoustic Classification and Optimization for Multi-Modal Rendering of Real-World Scenes.

    Science.gov (United States)

    Schissler, Carl; Loftin, Christian; Manocha, Dinesh

    2018-03-01

    We present a novel algorithm to generate virtual acoustic effects in captured 3D models of real-world scenes for multimodal augmented reality. We leverage recent advances in 3D scene reconstruction in order to automatically compute acoustic material properties. Our technique consists of a two-step procedure that first applies a convolutional neural network (CNN) to estimate the acoustic material properties, including frequency-dependent absorption coefficients, that are used for interactive sound propagation. In the second step, an iterative optimization algorithm is used to adjust the materials determined by the CNN until a virtual acoustic simulation converges to measured acoustic impulse responses. We have applied our algorithm to many reconstructed real-world indoor scenes and evaluated its fidelity for augmented reality applications.

  10. Places: A 10 million Image Database for Scene Recognition.

    Science.gov (United States)

    Zhou, Bolei; Lapedriza, Agata; Khosla, Aditya; Oliva, Aude; Torralba, Antonio

    2017-07-04

    The rise of multi-million-item dataset initiatives has enabled data-hungry machine learning algorithms to reach near-human semantic classification performance at tasks such as visual object and scene recognition. Here we describe the Places Database, a repository of 10 million scene photographs, labeled with scene semantic categories, comprising a large and diverse list of the types of environments encountered in the world. Using the state-of-the-art Convolutional Neural Networks (CNNs), we provide scene classification CNNs (Places-CNNs) as baselines, that significantly outperform the previous approaches. Visualization of the CNNs trained on Places shows that object detectors emerge as an intermediate representation of scene classification. With its high-coverage and high-diversity of exemplars, the Places Database along with the Places-CNNs offer a novel resource to guide future progress on scene recognition problems.

  11. Stimulant use among African American and Latino MSM social networking users.

    Science.gov (United States)

    Young, Sean D; Shoptaw, Steve

    2013-01-01

    High stimulant-using and at-risk HIV populations, such as African American and Latino men who have sex with men (MSM), are increasingly using social networking technologies. However, no known research has explored associations between stimulant use, sexual risk behaviors, and social networking among these populations. Participants were recruited using the Facebook Connect software application, which narrowed the sample to 118 (primarily African American and Latino MSM) active Facebook users. Participants completed demographic, Internet and social media use, and drug use survey items. Participants reported high rates of cocaine and methamphetamine use (both more than 15% within the past 12 months). More than 70% of participants reported using social networking technologies to meet people, and more than 30% used them to find sexual partners. A multivariate logistic regression showed that (1) participants using social networks to find sexual partners were more likely to have used methamphetamines within the past 12 months and (2) those who were more comfortable talking online compared to face-to-face had over 4 times the odds of methamphetamine use and over 6 times the odds of cocaine use within the past 12 months. Minority MSM who used social networks to meet men and find sexual partners had high risk for stimulant use. Understanding drug use among minority social networking users will provide insights to incorporate these technologies into drug prevention interventions.

  12. Hepatitis A outbreak among MSM linked to casual sex and gay saunas in Copenhagen, Denmark

    DEFF Research Database (Denmark)

    Mazick, A; Howitz, M; Rex, S

    2005-01-01

    .2-26.9). Eleven of 18 cases and 14/62 controls had sex in gay saunas (ORMH 4.2, 95% CI 1.5-11.5). Sex at private homes appeared to be protective (ORMH 0.2, 95% CI 0.1-0.7). Casual sex including sex in gay saunas was an important risk factor for the spread of HAV among MSM in Copenhagen. The results......During an outbreak of hepatitis A predominantly among men who have sex with men (MSM) in Copenhagen, Denmark, in 2004, we did a case-control study to determine risk factors for infection. A case was an MSM >17 years, living in Copenhagen, with IgM positive hepatitis A infection diagnosed between...... June and August 2004, and without a household contact with a hepatitis A case before onset of illness. Controls were selected at the Copenhagen Pride Festival. The study included 18 cases and 64 controls. Sixteen of 18 cases and 36/63 controls had sex with casual partners (ORMH 5.6, 95% CI 1...

  13. Challenges in Providing Counselling to MSM in Highly Stigmatized Contexts: Results of a Qualitative Study from Kenya

    Science.gov (United States)

    Taegtmeyer, Miriam; Davies, Alun; Mwangome, Mary; van der Elst, Elisabeth M.; Graham, Susan M.; Price, Matt A.; Sanders, Eduard J.

    2013-01-01

    The role of men who have sex with men (MSM) in the African HIV epidemic is gaining recognition yet capacity to address the HIV prevention needs of this group is limited. HIV testing and counselling is not only a critical entry point for biomedical HIV prevention interventions, such as pre-exposure prophylaxis, rectal microbicides and early treatment initiation, but is also an opportunity for focused risk reduction counselling that can support individuals living in difficult circumstances. For prevention efforts to succeed, however, MSM need to access services and they will only do so if these are non-judgmental, informative, focused on their needs, and of clear benefit. This study aimed to understand Kenyan providers' attitudes towards and experiences with counselling MSM in a research clinic targeting this group for HIV prevention. We used in-depth interviews to explore values, attitudes and cognitive and social constructs of 13 counsellors and 3 clinicians providing services to MSM at this clinic. Service providers felt that despite their growing experience, more targeted training would have been helpful to improve their effectiveness in MSM-specific risk reduction counselling. They wanted greater familiarity with MSM in Kenya to better understand the root causes of MSM risk-taking (e.g., poverty, sex work, substance abuse, misconceptions about transmission, stigma, and sexual desire) and felt frustrated at the perceived intractability of some of their clients' issues. In addition, they identified training needs on how to question men about specific risk behaviours, improved strategies for negotiating risk reduction with counselling clients, and improved support supervision from senior counsellors. This paper describes the themes arising from these interviews and makes practical recommendations on training and support supervision systems for nascent MSM HIV prevention programmes in Africa. PMID:23762241

  14. Estimating the Size of the MSM Population in Metro Vancouver, Canada, Using Multiple Methods and Diverse Data Sources.

    Science.gov (United States)

    Rich, Ashleigh J; Lachowsky, Nathan J; Sereda, Paul; Cui, Zishan; Wong, Jason; Wong, Stanley; Jollimore, Jody; Raymond, Henry Fisher; Hottes, Travis Salway; Roth, Eric A; Hogg, Robert S; Moore, David M

    2017-06-19

    Men who have sex with men (MSM) are disproportionately affected by HIV globally, regionally in Canada, and locally in Vancouver. Lack of reliable population size estimates of MSM impedes effective implementation of health care services and limits our understanding of the HIV epidemic. We estimated the population size of MSM residing in Metro Vancouver drawing on four data sources: the Canadian Community Health Survey (CCHS), a cross-sectional bio-behavioural MSM survey, HIV testing services data from sexually transmitted infection (STI) clinics serving MSM, and online social networking site Facebook. Estimates were calculated using (1) direct estimates from the CCHS, (2) "Wisdom of the Crowds" (WOTC), and (3) the multiplier method using data from a bio-behavioural MSM survey, clinic-based HIV testing, and online social media network site Facebook. Data sources requiring greater public disclosure of sexual orientation resulted in our mid-range population estimates (Facebook 23,760, CCHS 30,605). The WOTC method produced the lowest estimate, 10,000. The multiplier method using STI clinic HIV testing data produced the largest estimate, 41,777. The median of all estimates was 27,183, representing 2.9% of the Metro Vancouver census male adult population, with an interquartile range of 1.1-4.5%. Using multiple data sources, our estimates of the MSM population in Metro Vancouver are similar to population prevalence estimates based on population data from other industrialized nations. These findings will support understanding of the HIV burden among MSM and corresponding public health and health services planning for this key population.

  15. Hidden from health: structural stigma, sexual orientation concealment, and HIV across 38 countries in the European MSM Internet Survey.

    Science.gov (United States)

    Pachankis, John E; Hatzenbuehler, Mark L; Hickson, Ford; Weatherburn, Peter; Berg, Rigmor C; Marcus, Ulrich; Schmidt, Axel J

    2015-06-19

    Substantial country-level variation exists in prejudiced attitudes towards male homosexuality and in the extent to which countries promote the unequal treatment of MSM through discriminatory laws. The impact and underlying mechanisms of country-level stigma on odds of diagnosed HIV, sexual opportunities, and experience of HIV-prevention services, needs and behaviours have rarely been examined, however. Data come from the European MSM Internet Survey (EMIS), which was administered between June and August 2010 across 38 European countries (N = 174 209). Country-level stigma was assessed using a combination of national laws and policies affecting sexual minorities and a measure of attitudes held by the citizens of each country. We also assessed concealment, HIV status, number of past 12-month male sex partners, and eight HIV-preventive services, knowledge, and behavioural outcomes. MSM living in countries with higher levels of stigma had reduced odds of diagnosed HIV and fewer partners but higher odds of sexual risk behaviour, unmet prevention needs, not using testing services, and not discussing their sexuality in testing services. Sexual orientation concealment mediated associations between country-level stigma and these outcomes. Country-level stigma may have historically limited HIV transmission opportunities among MSM, but by restricting MSM's public visibility, it also reduces MSM's ability to access HIV-preventive services, knowledge and precautionary behaviours. These findings suggest that MSM in European countries with high levels of stigma are vulnerable to HIV infection. Although they have less opportunity to identify and contact other MSM, this might change with emerging technologies.

  16. The effect of time gaining on chemical composition and technological characteristics of mechanically separated turkey meat (MSM)

    OpenAIRE

    Aneta Cegiełka; Urszula Zakrzewska; Elżbieta Hać-Szymańczuk

    2016-01-01

    Mechanically separated meat (MSM) of poultry is a raw material widely used in the meat industry in Poland and most European Union countries. The manner and conditions for the production of this raw material cause, however, that it has limited technological usefulness. In this study the effect of time of obtaining turkey MSM produced by pressure separation on selected quality characteristics of this raw material: basic chemical composition, pH, thermal loss, water binding capacity and colour w...

  17. Challenges in providing counselling to MSM in highly stigmatized contexts: results of a qualitative study from Kenya.

    Directory of Open Access Journals (Sweden)

    Miriam Taegtmeyer

    Full Text Available The role of men who have sex with men (MSM in the African HIV epidemic is gaining recognition yet capacity to address the HIV prevention needs of this group is limited. HIV testing and counselling is not only a critical entry point for biomedical HIV prevention interventions, such as pre-exposure prophylaxis, rectal microbicides and early treatment initiation, but is also an opportunity for focused risk reduction counselling that can support individuals living in difficult circumstances. For prevention efforts to succeed, however, MSM need to access services and they will only do so if these are non-judgmental, informative, focused on their needs, and of clear benefit. This study aimed to understand Kenyan providers' attitudes towards and experiences with counselling MSM in a research clinic targeting this group for HIV prevention. We used in-depth interviews to explore values, attitudes and cognitive and social constructs of 13 counsellors and 3 clinicians providing services to MSM at this clinic. Service providers felt that despite their growing experience, more targeted training would have been helpful to improve their effectiveness in MSM-specific risk reduction counselling. They wanted greater familiarity with MSM in Kenya to better understand the root causes of MSM risk-taking (e.g., poverty, sex work, substance abuse, misconceptions about transmission, stigma, and sexual desire and felt frustrated at the perceived intractability of some of their clients' issues. In addition, they identified training needs on how to question men about specific risk behaviours, improved strategies for negotiating risk reduction with counselling clients, and improved support supervision from senior counsellors. This paper describes the themes arising from these interviews and makes practical recommendations on training and support supervision systems for nascent MSM HIV prevention programmes in Africa.

  18. Fast Binary Coding for the Scene Classification of High-Resolution Remote Sensing Imagery

    Directory of Open Access Journals (Sweden)

    Fan Hu

    2016-06-01

    Full Text Available Scene classification of high-resolution remote sensing (HRRS imagery is an important task in the intelligent processing of remote sensing images and has attracted much attention in recent years. Although the existing scene classification methods, e.g., the bag-of-words (BOW model and its variants, can achieve acceptable performance, these approaches strongly rely on the extraction of local features and the complicated coding strategy, which are usually time consuming and demand much expert effort. In this paper, we propose a fast binary coding (FBC method, to effectively generate efficient discriminative scene representations of HRRS images. The main idea is inspired by the unsupervised feature learning technique and the binary feature descriptions. More precisely, equipped with the unsupervised feature learning technique, we first learn a set of optimal “filters” from large quantities of randomly-sampled image patches and then obtain feature maps by convolving the image scene with the learned filters. After binarizing the feature maps, we perform a simple hashing step to convert the binary-valued feature map to the integer-valued feature map. Finally, statistical histograms computed on the integer-valued feature map are used as global feature representations of the scenes of HRRS images, similar to the conventional BOW model. The analysis of the algorithm complexity and experiments on HRRS image datasets demonstrate that, in contrast with existing scene classification approaches, the proposed FBC has much faster computational speed and achieves comparable classification performance. In addition, we also propose two extensions to FBC, i.e., the spatial co-occurrence matrix and different visual saliency maps, for further improving its final classification accuracy.

  19. Fixed Pattern Noise pixel-wise linear correction for crime scene imaging CMOS sensor

    Science.gov (United States)

    Yang, Jie; Messinger, David W.; Dube, Roger R.; Ientilucci, Emmett J.

    2017-05-01

    Filtered multispectral imaging technique might be a potential method for crime scene documentation and evidence detection due to its abundant spectral information as well as non-contact and non-destructive nature. Low-cost and portable multispectral crime scene imaging device would be highly useful and efficient. The second generation crime scene imaging system uses CMOS imaging sensor to capture spatial scene and bandpass Interference Filters (IFs) to capture spectral information. Unfortunately CMOS sensors suffer from severe spatial non-uniformity compared to CCD sensors and the major cause is Fixed Pattern Noise (FPN). IFs suffer from "blue shift" effect and introduce spatial-spectral correlated errors. Therefore, Fixed Pattern Noise (FPN) correction is critical to enhance crime scene image quality and is also helpful for spatial-spectral noise de-correlation. In this paper, a pixel-wise linear radiance to Digital Count (DC) conversion model is constructed for crime scene imaging CMOS sensor. Pixel-wise conversion gain Gi,j and Dark Signal Non-Uniformity (DSNU) Zi,j are calculated. Also, conversion gain is divided into four components: FPN row component, FPN column component, defects component and effective photo response signal component. Conversion gain is then corrected to average FPN column and row components and defects component so that the sensor conversion gain is uniform. Based on corrected conversion gain and estimated image incident radiance from the reverse of pixel-wise linear radiance to DC model, corrected image spatial uniformity can be enhanced to 7 times as raw image, and the bigger the image DC value within its dynamic range, the better the enhancement.

  20. Non-disclosure of Sexual Orientation to Parents Associated with Sexual Risk Behaviors Among Gay and Bisexual MSM in China.

    Science.gov (United States)

    Zhao, Ye; Ma, Ying; Chen, Ren; Li, Feng; Qin, Xia; Hu, Zhi

    2016-01-01

    The objective of this study was to explore the relationship between non-disclosure of sexual orientation to parents and sexual risk behaviors among gay and bisexual men who have sex with men (MSM) in China. A total of 295 eligible participants (gay n = 179, bisexual n = 116) were recruited from MSM venues and MSM organizations in Anhui Province, China. Overall, 16.6 % of participants chose to disclose their sexual orientation to parents. Fewer bisexual participants chose to disclose their sexual orientation than gay participants (9.5 vs. 21.2 %, p gay and bisexual MSM (AOR = 2.91), non-disclosure of sexual orientation to parents was positively associated with the number of female sex partners (AOR = 3.40) and with engagement in unprotected anal intercourse with men (AOR = 2.49) among gay MSM, in the past 6 months. Our findings indicated that HIV/AIDS intervention programs should promote the disclosure of sexual orientation and should design interventions specific to gay and bisexual MSM separately.

  1. The network structure of sex partner meeting places reported by HIV-infected MSM: Opportunities for HIV targeted control.

    Science.gov (United States)

    Brantley, Meredith; Schumacher, Christina; Fields, Errol L; Perin, Jamie; Safi, Amelia Greiner; Ellen, Jonathan M; Muvva, Ravikiran; Chaulk, Patrick; Jennings, Jacky M

    2017-06-01

    Baltimore, Maryland ranks among U.S. cities with the highest incidence of HIV infection among men who have sex with men (MSM). HIV screening at sex partner meeting places or venues frequented by MSM with new diagnoses and/or high HIV viral load may reduce transmission by identifying and linking infected individuals to care. We investigated venue-based clustering of newly diagnosed MSM to identify high HIV transmission venues. HIV surveillance data from MSM diagnosed between October 2012-June 2014 and reporting ≥1 sex partner meeting place were examined. Venue viral load was defined according to the geometric mean viral load of the cluster of cases that reported the venue and classified as high (>50,000 copies/mL), moderate (1500-50,000 copies/mL), and low (place, accounting for 132 unique venues. Twenty-six venues were reported by > 1 MSM; of these, a tightly connected cluster of six moderate viral load sex partner meeting places emerged, representing 66% of reports. Small, dense networks of moderate to high viral load venues may be important for targeted HIV control among MSM. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. Estimating the size of the MSM populations for 38 European countries by calculating the survey-surveillance discrepancies (SSD) between self-reported new HIV diagnoses from the European MSM internet survey (EMIS) and surveillance-reported HIV diagnoses among MSM in 2009.

    Science.gov (United States)

    Marcus, Ulrich; Hickson, Ford; Weatherburn, Peter; Schmidt, Axel J

    2013-10-03

    Comparison of rates of newly diagnosed HIV infections among MSM across countries is challenging for a variety of reasons, including the unknown size of MSM populations. In this paper we propose a method of triangulating surveillance data with data collected in a pan-European MSM Internet Survey (EMIS) to estimate the sizes of the national MSM populations and the rates at which HIV is being diagnosed amongst them by calculating survey-surveillance discrepancies (SSD) as a measure of selection biases of survey participants. In 2010, the first EMIS collected self-reported data on HIV diagnoses among more than 180,000 MSM in 38 countries of Europe. These data were compared with data from national HIV surveillance systems to explore possible sampling and reporting biases in the two approaches. The Survey-Surveillance Discrepancy (SSD) represents the ratio of survey members diagnosed in 2009 (HIVsvy) to total survey members (Nsvy), divided by the ratio of surveillance reports of diagnoses in 2009 (HIVpop) to the estimated total MSM population (Npop). As differences in household internet access may be a key component of survey selection biases, we analysed the relationship between household internet access and SSD in countries conducting consecutive MSM internet surveys at different time points with increasing levels of internet access. The empirically defined SSD was used to calculate the respective MSM population sizes (Npop), using the formula Npop = HIVpop*Nsvy*SSD/HIVsvy. Survey-surveillance discrepancies for consecutive MSM internet surveys between 2003 and 2010 with different levels of household internet access were best described by a potential equation, with high SSD at low internet access, declining to a level around 2 with broad access. The lowest SSD was calculated for the Netherlands with 1.8, the highest for Moldova with 9.0. Taking the best available estimate for surveillance reports of HIV diagnoses among MSM in 2009 (HIVpop), the relative MSM population

  3. Global scene layout modulates contextual learning in change detection.

    Science.gov (United States)

    Conci, Markus; Müller, Hermann J

    2014-01-01

    Change in the visual scene often goes unnoticed - a phenomenon referred to as "change blindness." This study examined whether the hierarchical structure, i.e., the global-local layout of a scene can influence performance in a one-shot change detection paradigm. To this end, natural scenes of a laid breakfast table were presented, and observers were asked to locate the onset of a new local object. Importantly, the global structure of the scene was manipulated by varying the relations among objects in the scene layouts. The very same items were either presented as global-congruent (typical) layouts or as global-incongruent (random) arrangements. Change blindness was less severe for congruent than for incongruent displays, and this congruency benefit increased with the duration of the experiment. These findings show that global layouts are learned, supporting detection of local changes with enhanced efficiency. However, performance was not affected by scene congruency in a subsequent control experiment that required observers to localize a static discontinuity (i.e., an object that was missing from the repeated layouts). Our results thus show that learning of the global layout is particularly linked to the local objects. Taken together, our results reveal an effect of "global precedence" in natural scenes. We suggest that relational properties within the hierarchy of a natural scene are governed, in particular, by global image analysis, reducing change blindness for local objects through scene learning.

  4. Global scene layout modulates contextual learning in change detection

    Directory of Open Access Journals (Sweden)

    Markus eConci

    2014-02-01

    Full Text Available Change in the visual scene often goes unnoticed – a phenomenon referred to as ‘change blindness’. This study examined whether the hierarchical structure, i.e., the global-local layout of a scene can influence performance in a one-shot change detection paradigm. To this end, natural scenes of a laid breakfast table were presented, and observers were asked to locate the onset of a new local object. Importantly, the global structure of the scene was manipulated by varying the relations among objects in the scene layouts. The very same items were either presented as global-congruent (typical layouts or as global-incongruent (random arrangements. Change blindness was less severe for congruent than for incongruent displays, and this congruency benefit increased with the duration of the experiment. These findings show that global layouts are learned, supporting detection of local changes with enhanced efficiency. However, performance was not affected by scene congruency in a subsequent control experiment that required observers to localize a static discontinuity (i.e., an object that was missing from the repeated layouts. Our results thus show that learning of the global layout is particularly linked to the local objects. Taken together, our results reveal an effect of global precedence in natural scenes. We suggest that relational properties within the hierarchy of a natural scene are governed, in particular, by global image analysis, reducing change blindness for local objects through scene learning.

  5. Scenes as Micro-Cultures: Examining Heterogeneity of HIV Risk Behavior Among Gay, Bisexual, and Other Men Who Have Sex with Men in Toronto, Canada.

    Science.gov (United States)

    Noor, Syed W; Adam, Barry D; Brennan, David J; Moskowitz, David A; Gardner, Sandra; Hart, Trevor A

    2018-01-01

    Using latent class analysis (LCA), we examined patterns of participation in multiple scenes, how sexual risk practices vary by scene, and psychosocial factors associated with these patterns among 470 gay, bisexual, and other men who have sex with men (GBM) recruited from Toronto. We calculated posterior probability of being in a class from participation in nine separate scenes. We used Entropy, the Bayesian information criterion and the Lo-Mendel-Rubin likelihood ratio test to identify the best fit model. Fit indices suggested a four-class solution. Half (50%) of the GBM reported no or minimal participation in any scene, 28% reported participating in the dance club scene, 16% reported participating in the BDSM, bear, and leather scenes, and 6% reported participating in circuit, party and play, and sex party scenes. Compared to GBM who did not participate in scenes, GBM participating in the BDSM-Bear-Leather scene were more likely to be older, white, to report higher sexual self-esteem, and to engage in condomless anal sex; Party and Play scene members were more likely to be of Asian origin, and to use drugs before and during sex, whereas Dance Club scene members were more likely to be younger and to report lower self-esteem but higher hope. LCA allowed us to identify distinct social niches or micro-cultures and factors characterizing these micro-cultures. GBM differ in their risk for HIV and STIs according to characteristics associated with participation in distinct micro-cultures associated with scenes. Tailored interventions may be needed that focus on reducing HIV risk and promoting sexual health in specific contexts such as the BDSM-Bear-Leather and Party and Play.

  6. Attention Switching during Scene Perception: How Goals Influence the Time Course of Eye Movements across Advertisements

    Science.gov (United States)

    Wedel, Michel; Pieters, Rik; Liechty, John

    2008-01-01

    Eye movements across advertisements express a temporal pattern of bursts of respectively relatively short and long saccades, and this pattern is systematically influenced by activated scene perception goals. This was revealed by a continuous-time hidden Markov model applied to eye movements of 220 participants exposed to 17 ads under a…

  7. Crosstalk Analysis of a Deformable-Mirror Infrared Scene Projector.

    Science.gov (United States)

    Barnard, Kenneth J.

    The design of an infrared scene projector that incorporates a deformable mirror device (DMD) as an infrared spatial light modulator (SLM) is presented. A numerical model is developed to determine crosstalk effects in the projected image. Partial-coherence effects due to the physical layout of the projection system are included in the development. It is shown both analytically and numerically that under quasimonochromatic illumination the system behaves coherently and can be modeled as such. Polychromatic image formation is approximated as a summation of quasimonochromatic images over the wavelength band. Crosstalk is determined by defining a contrast ratio in the projected image. Contrast -ratio calculations are carried out for monochromatic and blackbody projection sources over the 3- to 5- μm wavelength band. The results predict contrast ratios of 265:1, 1217:1, and 2437:1 for deformable -mirror pixels of 50 mum, 100 mum, and 150 mum. The derivation of the contrast-ratio model leads to the determination of an upper limit on the system aperture-stop diameter for optimum contrast performance. Diffraction effects are the fundamental cause of crosstalk, and it is shown that crosstalk performance improves with shorter wavelengths and for larger deformable-mirror pixels. The effects of angular misalignment of the illumination source are also investigated. The results show that the reduced contrast ratio resulting from a small angular misalignment Deltatheta along the DMD-pixel-tilt direction can be approximated by computing the contrast ratio for a reduced-diameter aperture stop. The results of a proof-of-principle demonstration that verifies the feasibility of a deformable-mirror-based infrared scene projection system are also included.

  8. Using Ignorance in 3D Scene Understanding

    Directory of Open Access Journals (Sweden)

    Bogdan Harasymowicz-Boggio

    2014-01-01

    Full Text Available Awareness of its own limitations is a fundamental feature of the human sight, which has been almost completely omitted in computer vision systems. In this paper we present a method of explicitly using information about perceptual limitations of a 3D vision system, such as occluded areas, limited field of view, loss of precision along with distance increase, and imperfect segmentation for a better understanding of the observed scene. The proposed mechanism integrates metric and semantic inference using Dempster-Shafer theory, which makes it possible to handle observations that have different degrees and kinds of uncertainty. The system has been implemented and tested in a real indoor environment, showing the benefits of the proposed approach.

  9. Algorithms for Graph Rigidity and Scene Analysis

    DEFF Research Database (Denmark)

    Berg, Alex Rune; Jordán, Tibor

    2003-01-01

    We investigate algorithmic questions and structural problems concerning graph families defined by `edge-counts'. Motivated by recent developments in the unique realization problem of graphs, we give an efficient algorithm to compute the rigid, redundantly rigid, M-connected, and globally rigid...... components of a graph. Our algorithm is based on (and also extends and simplifies) the idea of Hendrickson and Jacobs, as it uses orientations as the main algorithmic tool. We also consider families of bipartite graphs which occur in parallel drawings and scene analysis. We verify a conjecture of Whiteley...... by showing that 2d-connected bipartite graphs are d-tight. We give a new algorithm for finding a maximal d-sharp subgraph. We also answer a question of Imai and show that finding a maximum size d-sharp subgraph is NP-hard....

  10. [A doctor's action within possible crime scene].

    Science.gov (United States)

    Sowizdraniuk, Joanna

    2016-01-01

    Every doctor regardless of specialization in his practice may meet the need to provide assistance to victims of crime-related action. In this article there were disscused the issues of informing the investigative authorities about the crime, ensuring the safety of themselves and the environment at the scene. It also shows the specific elements of necessary procedures and practice to deal with the victims designed to securing any evidence present of potential or committed crime in proper manner. Special attention has been given to medical operation and other, necessary in case of certain criminal groups, among the latter we need to underline: actions against sexual freedom and decency, bodily integrity, life and well-being of human, and specially homicide, infanticide and suicide.

  11. The scene is set for ALICE

    CERN Multimedia

    2008-01-01

    Now that the electromagnetic calorimeter support and the mini space frame have been installed, practically all ALICE’s infrastructure is in place. The calorimeter support, an austenitic stainless steel shell weighing 30 tonnes, was slid gently inside the detector, in between the face of the magnet and the space frame. With the completion of two major installation projects, the scene is finally set for the ALICE experiment…or at least it nearly is, as a few design studies, minor installation jobs and measurements still need to be carried out before the curtain can finally be raised. The experiment’s chief engineer Diego Perini confirms: "All the heavy infrastructure for ALICE has been in place and ready for the grand opening since December 2007." The next step will be the installation of additional modules on the TOF and TRD detectors between January and March 2008, and physicists have already started testing the equipment with co...

  12. The cost-effectiveness in the use of HIV counselling and testing-mobile outreaches in reaching men who have sex with men (MSM) in northern Nigeria.

    Science.gov (United States)

    Ifekandu, Chiedu; Suleiman, Aliyu; Aniekwe, Ogechukwu

    2014-01-01

    Men who have sex with men (MSM) are at increased risk of HIV and other STI infections in Nigeria. This is because MSM are afraid to seek medical help because the healthcare workers in various facilities are afraid of the consequences if they provide services for MSM citing the law as a reason not to intervene. MSM in northern states of Nigeria are facing double-jeopardy because the few international partners working in MSM in Nigeria are pulling out of these volatile areas because of the fear of attacks by the Boko Haram and the Nigerian law enforcement agencies. The intervention was conducted to promote affordable and sustainable HIV care and treatment for MSM in Nigeria. This intervention was conducted in the Boko Haram ravaged cities of Kano and Maiduguri (North-East Nigeria). Twenty MSM-key influencers from the two cities were identified and trained on HIV counselling and testing, caregivers, case managers and on initiation process for ARV treatment for new HIV+MSM as well as ethical considerations. The mean age of the key influencers was 24 years +/-SD. Each of the trained 20 key influencers reached 20 MSM-peer with condom promotion, HCT, referral to identified MSM-community health centers and follow-up/caregiving within the space of one month. The project was able to reach 400 MSM in the two cities. 89% of the peers consented to HCT. HIV prevalence among the participants was at 18%. The project recorded ARV-successful referral to healthcare facilities for the respondents that tested positive. The key influencers have been following up for ARV-adherence. Use of community members should be promoted for sustainability and ownership. It also helps in eradicating socio-cultural barrier to HIV intervention for MSM. Moreover, this proves to be one of the safest and affordable methods of reaching MSM in Nigeria in this ugly time of legalization of homophobia in the country's constitution.

  13. Applying horizontal diffusion on pressure surface to mesoscale models on terrain-following coordinates

    Science.gov (United States)

    Hann-Ming Henry Juang; Ching-Teng Lee; Yongxin Zhang; Yucheng Song; Ming-Chin Wu; Yi-Leng Chen; Kevin Kodama; Shyh-Chin Chen

    2005-01-01

    The National Centers for Environmental Prediction regional spectral model and mesoscale spectral model (NCEP RSM/MSM) use a spectral computation on perturbation. The perturbation is defined as a deviation between RSM/MSM forecast value and their outer model or analysis value on model sigma-coordinate surfaces. The horizontal diffusion used in the models applies...

  14. Contrast analysis for DMD-based IR scene projector

    Science.gov (United States)

    Rentz Dupuis, Julia; Mansur, David J.; Grant, Samuel; Newbry, Scott P.

    2012-06-01

    OPTRA has developed a two-band midwave infrared (MWIR) scene projector based on digital micromirror device (DMD) technology; the projector is intended for training various IR tracking systems that exploit the relative intensities of two separate MWIR spectral bands. Next generation tracking systems have increasing dynamic range requirements which current DMD-based projector test equipment is not capable of meeting. While sufficient grayscale digitization can be achieved with current drive electronics, commensurate contrast is not currently available. It is towards this opportunity that OPTRA has initiated a dynamic range design improvement effort. In this paper we present our work towards the measurement and analysis of contrast limiting factors including substrate scattering, diffraction, and flat state emissivity. We summarize the results of an analytical model which indicates the largest contributions to background energy in the off state. We present the methodology and results from a series of breadboard tests designed to characterize these contributions. Finally, we suggest solutions to counter these contributions.

  15. Sound Classification in Hearing Aids Inspired by Auditory Scene Analysis

    Science.gov (United States)

    Büchler, Michael; Allegro, Silvia; Launer, Stefan; Dillier, Norbert

    2005-12-01

    A sound classification system for the automatic recognition of the acoustic environment in a hearing aid is discussed. The system distinguishes the four sound classes "clean speech," "speech in noise," "noise," and "music." A number of features that are inspired by auditory scene analysis are extracted from the sound signal. These features describe amplitude modulations, spectral profile, harmonicity, amplitude onsets, and rhythm. They are evaluated together with different pattern classifiers. Simple classifiers, such as rule-based and minimum-distance classifiers, are compared with more complex approaches, such as Bayes classifier, neural network, and hidden Markov model. Sounds from a large database are employed for both training and testing of the system. The achieved recognition rates are very high except for the class "speech in noise." Problems arise in the classification of compressed pop music, strongly reverberated speech, and tonal or fluctuating noises.

  16. Fixation and saliency during search of natural scenes: the case of visual agnosia.

    Science.gov (United States)

    Foulsham, Tom; Barton, Jason J S; Kingstone, Alan; Dewhurst, Richard; Underwood, Geoffrey

    2009-07-01

    Models of eye movement control in natural scenes often distinguish between stimulus-driven processes (which guide the eyes to visually salient regions) and those based on task and object knowledge (which depend on expectations or identification of objects and scene gist). In the present investigation, the eye movements of a patient with visual agnosia were recorded while she searched for objects within photographs of natural scenes and compared to those made by students and age-matched controls. Agnosia is assumed to disrupt the top-down knowledge available in this task, and so may increase the reliance on bottom-up cues. The patient's deficit in object recognition was seen in poor search performance and inefficient scanning. The low-level saliency of target objects had an effect on responses in visual agnosia, and the most salient region in the scene was more likely to be fixated by the patient than by controls. An analysis of model-predicted saliency at fixation locations indicated a closer match between fixations and low-level saliency in agnosia than in controls. These findings are discussed in relation to saliency-map models and the balance between high and low-level factors in eye guidance.

  17. Visualizing fMRI BOLD responses to diverse naturalistic scenes using retinotopic projection.

    Science.gov (United States)

    Zipser, Karl

    2017-06-01

    To view brain activity in register with visual stimuli, a technique here referred to as "retinotopic projection," which translates functional measurements into retinotopic space, is employed. Retinotopic projection is here first applied to a previously acquired fMRI dataset in which a large set of grayscale photos of real scenes were presented to three subjects. A simple model of local contrast integration accounts for much of the data in early visual areas (V1 and V2). However, consistent discrepancies were discovered: Human faces tend to evoke stronger responses relative to other scene elements than predicted by the model, whereas periodic patterns evoke weaker responses than predicted by the model. Next, in new fMRI experiments, three subjects directed attention toward various elements of naturalistic scenes (Vermeer paintings). Retinotopic projection applied to these data showed that attending to an object increased activation in cortex corresponding to the location of that object. Together the results suggest that even during passive viewing, the visual system differentially processes natural scenes in a manner consistent with deployment of visual attention to salient elements.

  18. Characterization, propagation, and simulation of infrared scenes; Proceedings of the Meeting, Orlando, FL, Apr. 16-20, 1990

    Science.gov (United States)

    Watkins, Wendell R.; Zegel, Ferdinand H.; Triplett, Milton J.

    1990-09-01

    Various papers on the characterization, propagation, and simulation of IR scenes are presented. Individual topics addressed include: total radiant exitance measurements, absolute measurement of diffuse and specular reflectance using an FTIR spectrometer with an integrating sphere, fundamental limits in temperature estimation, incorporating the BRDF into an IR scene-generation system, characterizing IR dynamic response for foliage backgrounds, modeling sea surface effects in FLIR performance codes, automated imaging IR seeker performance evaluation system, generation of signature data bases with fast codes, background measurements using the NPS-IRST system. Also discussed are: naval ocean IR background analysis, camouflage simulation and effectiveness assessment for the individual soldier, discussion of IR scene generators, multiwavelength Scophony IR scene projector, LBIR target generator and calibrator for preflight seeker tests, dual-mode hardware-in-the-loop simulation facility, development of the IR blackbody source of gravity-type heat pipe and study of its characteristic.

  19. Pleasure, affection, and love among Black men who have sex with men (MSM) versus MSM of other races: countering dehumanizing stereotypes via cross-race comparisons of reported sexual experience at last sexual event.

    Science.gov (United States)

    Calabrese, Sarah K; Rosenberger, Joshua G; Schick, Vanessa R; Novak, David S

    2015-10-01

    Black men have historically been stereotyped as hedonistic, aggressive, and animalistic in their sexual interactions. This study sought to describe pleasure, affection, and love experienced by Black men who have sex with men (MSM) during their last male-partnered sexual event and to examine differences relative to White, Latino, and Asian MSM. A total of 21,696 (793 Black, 18,905 White, 1,451 Latino, and 547 Asian) U.S. men ages 18-87 (M Age = 39) were recruited from social/sexual networking sites targeting MSM in 2010-2011. Participants reported multiple dimensions of sexual experience (pleasure, affection, and love) occurring at their last male-partnered sexual event, partner relationship, and sociodemographic characteristics. Across relationship categories, a sizeable percentage of Black MSM reported pleasure (72-87  % orgasmed, 57-82 % experienced high subjective pleasure) and affection (70-91 % kissed, 47-90 % cuddled). Love was primarily reported for events involving main partners (felt love for partner: 96 %; felt loved by partner: 97 %; verbalized love to partner: 89 %). Latent class analysis with MSM of all races, adjusting for partner relationship and sociodemographic characteristics, revealed three distinct profiles of sexual experience: affection and love (Class 1); affection in the absence of love (Class 2); and neither affection nor love (Class 3). Pleasure was probable across profiles. Some racial differences in profile probability were present, but no overall pattern emerged. Contrary to Black male stereotypes, Black MSM commonly reported pleasure, affection, and love at their last male-partnered sexual event and did not show a meaningful pattern of difference from other-race MSM in their likelihood of experiencing all three.

  20. Informational factors in identifying environmental sounds in natural auditory scenes.

    Science.gov (United States)

    Leech, Robert; Gygi, Brian; Aydelott, Jennifer; Dick, Frederic

    2009-12-01

    In a non-linguistic analog of the "cocktail-party" scenario, informational and contextual factors were found to affect the recognition of everyday environmental sounds embedded in naturalistic auditory scenes. Short environmental sound targets were presented in a dichotic background scene composed of either a single stereo background scene or a composite background scene created by playing different background scenes to the different ears. The side of presentation, time of onset, and number of target sounds were varied across trials to increase the uncertainty for the participant. Half the sounds were contextually congruent with the background sound (i.e., consistent with the meaningful real-world sound environment represented in the auditory scene) and half were incongruent. The presence of a single competing background scene decreased identification accuracy, suggesting an informational masking effect. In tandem, there was a contextual pop-out effect, with contextually incongruent sounds identified more accurately. However, when targets were incongruent with the real-world context of the background scene, informational masking was reduced. Acoustic analyses suggested that this contextual pop-out effect was driven by a mixture of perceptual differences between the target and background, as well as by higher-level cognitive factors. These findings indicate that identification of environmental sounds in naturalistic backgrounds is an active process that requires integrating perceptual, attentional, and cognitive resources.

  1. Developing Scene Understanding Neural Software for Realistic Autonomous Outdoor Missions

    Science.gov (United States)

    2017-09-01

    salient objects and environments providing mutual context (i.e., a primary or key object in an outdoor scene embedded in a realistic environmental ...tracking: a two part vision system for small robot navigation in forested environment . Proc. SPIE 8387, Unmanned Systems Technology XIV Conference; 2012...of realistic autonomous outdoor missions in complex and changing environments . Scene understanding for realistic outdoor missions has been

  2. The Influence of Color on the Perception of Scene Gist

    Science.gov (United States)

    Castelhano, Monica S.; Henderson, John M.

    2008-01-01

    In 3 experiments the authors used a new contextual bias paradigm to explore how quickly information is extracted from a scene to activate gist, whether color contributes to this activation, and how color contributes, if it does. Participants were shown a brief presentation of a scene followed by the name of a target object. The target object could…

  3. Mental Layout Extrapolations Prime Spatial Processing of Scenes

    Science.gov (United States)

    Gottesman, Carmela V.

    2011-01-01

    Four experiments examined whether scene processing is facilitated by layout representation, including layout that was not perceived but could be predicted based on a previous partial view (boundary extension). In a priming paradigm (after Sanocki, 2003), participants judged objects' distances in photographs. In Experiment 1, full scenes (target),…

  4. Emotional Scene Content Drives the Saccade Generation System Reflexively

    Science.gov (United States)

    Nummenmaa, Lauri; Hyona, Jukka; Calvo, Manuel G.

    2009-01-01

    The authors assessed whether parafoveal perception of emotional content influences saccade programming. In Experiment 1, paired emotional and neutral scenes were presented to parafoveal vision. Participants performed voluntary saccades toward either of the scenes according to an imperative signal (color cue). Saccadic reaction times were faster…

  5. Toward seamless multiview scene analysis from satellite to street level

    NARCIS (Netherlands)

    Lefevre, Sebastien; Tuia, Devis; Wegner, Jan Dirk; Produit, Timothee; Nassar, Ahmed Samy

    2017-01-01

    In this paper, we discuss and review how combined multiview imagery from satellite to street level can benefit scene analysis. Numerous works exist that merge information from remote sensing and images acquired from the ground for tasks such as object detection, robots guidance, or scene

  6. Robust Scene Categorization by Learning Image Statistics in Context

    NARCIS (Netherlands)

    van Gemert, J.C.; Geusebroek, J.M.; Veenman, C.J.; Snoek, C.G.M.; Smeulders, A.W.M.

    2006-01-01

    We present a generic and robust approach for scene categorization. A complex scene is described by proto-concepts like vegetation, water, fire, sky etc. These proto-concepts are represented by low level features, where we use natural images statistics to compactly represent color invariant texture

  7. Predisposing, Enabling and Reinforcing Factors of the Utilization of VCT by Men Who Have Sex with Men (MSM

    Directory of Open Access Journals (Sweden)

    Risanita Diah Fatmala

    2016-11-01

    Full Text Available MSM have a higher risk of HIV infection due to their multiple sexual partner behaviour and the anal intercourse practices. The incidence of HIV and AIDS by MSM is increasing compared to the years before. VCT is one of the effective strategies of HIV and AIDS prevention and treatment. Whereas the access to VCT services by MSM is still considered as low by the reason of the stigma and stereotypes against MSM and HIV and AIDS itself. The study is intended to explore the factors related to the MSM willingness to conduct VCT. This study used a qualitative method. We identified 9 key informants through snowball sampling method at IGAMA Malang. Data was collected by in-depth interview, analyzing descriptively, and presenting in a narrative. The results show that most of the informants has an adequate of knowledge concerning the VCT, HIV and AIDS. However, access to VCT services is still constrained by the schedule since most of the services are in the work days. The impetus for accessing VCT derived largely from community friends. With respect to the societal stigma and discrimination towards homosexuals, we did not recognize personal stigmatizing attitude and discriminatory behaviors by health workers. It makes them feel convenient because they are familiar to the health workers. The conclusion was that factors associated with the utilization of VCT service by MSM includes knowledge, perception, information, availability of the services, peer supports, and the attitudes or behavior of health workers. We suggested that VCT services would be better if could be performed also in the weekends. Keywords: HIV and AIDS, Men Who Have Sex with Men (MSM, VCT utilization

  8. Risk factors for HIV and unprotected anal intercourse among men who have sex with men (MSM in Almaty, Kazakhstan.

    Directory of Open Access Journals (Sweden)

    Mark Berry

    Full Text Available INTRODUCTION: Men who have sex with men (MSM are at high risk for HIV infection. MSM in Central Asia, however, are not adequately studied to assess their risk of HIV transmission. METHODS: This study used respondent driven sampling methods to recruit 400 MSM in Almaty, the largest city in Kazakhstan, into a cross-sectional study. Participation involved a one-time interviewer-administered questionnaire and rapid HIV screening test. Prevalence data were adjusted for respondent network size and recruitment patterns. Multivariate logistic regression was used to investigate the association between HIV and selected risk factors, and unprotected anal intercourse (UAI and selected risk factors. RESULTS: After respondent driven sampling (RDS weighted analysis, 20.2% of MSM were HIV-positive, and 69.0% had unprotected sex with at least one male partner in the last 12 months. Regression analysis showed that HIV infection was associated with unprotected receptive anal sex (AOR: 2.00; 95% CI: 1.04-3.84. Having unprotected anal intercourse with male partners, a measure of HIV risk behaviors, was associated with being single (AOR: 0.38; 95% CI: 0.23-0.64; very difficult access to lubricants (AOR: 11.08; 95% CI: 4.93-24.91; STI symptoms (AOR: 3.45; 95% CI: 1.42-8.40; transactional sex (AOR: 3.21; 95% CI: 1.66-6.22; and non-injection drug use (AOR: 3.10; 95% CI: 1.51-6.36. CONCLUSIONS: This study found a high HIV prevalence among MSM in Almaty, and a population of MSM engaging in multiple high-risk behavior in Almaty. Greater access to HIV education and prevention interventions is needed to limit the HIV epidemic among MSM in Almaty.

  9. High acceptability of rapid HIV self-testing among a diverse sample of MSM from Buenos Aires, Argentina.

    Directory of Open Access Journals (Sweden)

    Maria A Pando

    Full Text Available The objective of this study was to explore the acceptability of rapid HIV self-testing (RHST among men who have sex with men (MSM.During 2006-2009, a sample of 500 MSM was recruited through Respondent Driven Sampling for an HIV prevalence/incidence study. Attitude toward RHST was explored among HIV negative MSM. Data were weighted prior to analyses.Participants reported they were likely to buy RHST (74%, test themselves more frequently than they currently do (77%, and that the procedure would simplify testing (70%. Furthermore, 71% reported they would probably use it alone, 66% would use it with a steady partner, and 56% with a friend/partner. While a majority acknowledged that RHST use would deprive them of receiving counseling (61%, 74% declared they would go for help if they tested positive; 57% would use an RHST in order to avoid condoms. Probability of use surpassed 70% among gay and non-gay identified MSM as well as those with and without a previous HIV test. Those likely to buy RHST were older (p = 0.025 and more likely to identify as gay (p = 0.036. A total of 17% said they would think about killing themselves and 9% would attempt suicide if they tested positive. These MSM were more likely to be younger (p<0.001, with lower mood level (p<0.001 and greater feelings of loneliness (p = 0.026.The high acceptability of RHST found among MSM should encourage the authorities to consider the possibility of offering it for self-testing, as it can improve early diagnosis and prevention of future transmissions. However, further research is needed to understand how to best disseminate RHST among MSM who wish to use it and to offer support and linkage to care for those who test HIV-positive.

  10. Indoor scene classification of robot vision based on cloud computing

    Science.gov (United States)

    Hu, Tao; Qi, Yuxiao; Li, Shipeng

    2016-07-01

    For intelligent service robots, indoor scene classification is an important issue. To overcome the weak real-time performance of conventional algorithms, a new method based on Cloud computing is proposed for global image features in indoor scene classification. With MapReduce method, global PHOG feature of indoor scene image is extracted in parallel. And, feature eigenvector is used to train the decision classifier through SVM concurrently. Then, the indoor scene is validly classified by decision classifier. To verify the algorithm performance, we carried out an experiment with 350 typical indoor scene images from MIT LabelMe image library. Experimental results show that the proposed algorithm can attain better real-time performance. Generally, it is 1.4 2.1 times faster than traditional classification methods which rely on single computation, while keeping stable classification correct rate as 70%.

  11. Improving text recognition by distinguishing scene and overlay text

    Science.gov (United States)

    Quehl, Bernhard; Yang, Haojin; Sack, Harald

    2015-02-01

    Video texts are closely related to the content of a video. They provide a valuable source for indexing and interpretation of video data. Text detection and recognition task in images or videos typically distinguished between overlay and scene text. Overlay text is artificially superimposed on the image at the time of editing and scene text is text captured by the recording system. Typically, OCR systems are specialized on one kind of text type. However, in video images both types of text can be found. In this paper, we propose a method to automatically distinguish between overlay and scene text to dynamically control and optimize post processing steps following text detection. Based on a feature combination a Support Vector Machine (SVM) is trained to classify scene and overlay text. We show how this distinction in overlay and scene text improves the word recognition rate. Accuracy of the proposed methods has been evaluated by using publicly available test data sets.

  12. [Factors Influencing Post Traumatic Stress Disorder in Crime Scene Investigators].

    Science.gov (United States)

    Nho, Seon Mi; Kim, Eun A

    2017-02-01

    The purpose of this study was to verify the relationships among social support, resilience and post traumatic stress disorder (PTSD), and especially to identify factors influencing PTSD in police crime scene investigators. A cross-sectional design was used, with a convenience sample of 226 police crime scene investigators from 7 Metropolitan Police Agencies. Data were collected through self-report questionnaires during July and August, 2015. Data were analyzed using t-test, χ²-test, Fisher's exact test, and binary logistic regression analysis with SPSS/WIN 21.0 program. The mean score for PTSD in police crime scene investigators was 13.69. 11 points. Of the crime scene investigators 181 (80.1%) were in the low-risk group and 45 (19.9%) in high-risk group. Social support (t=5.68, pcrime scene investigators, intervention programs including social support and strategies to increase should be established.

  13. Tu Amigo Pepe: Evaluation of a Multi-media Marketing Campaign that Targets Young Latino Immigrant MSM with HIV Testing Messages.

    Science.gov (United States)

    Solorio, Rosa; Norton-Shelpuk, Pamela; Forehand, Mark; Montaño, Daniel; Stern, Joshua; Aguirre, Joel; Martinez, Marcos

    2016-09-01

    Latino immigrant men who have sex with men (MSM) are at risk for HIV and delayed diagnosis in the United States. This paper describes the evaluation of a pilot of the Tu Amigo Pepe, a multimedia HIV testing campaign aimed at Latino MSM in Seattle, WA particularly targeting immigrants who may not identify as gay, ages 18-30 years old. The 16-week campaign included Spanish-language radio public service announcements (PSAs), a Web site, social media outreach, a reminder system using mobile technology, print materials and a toll-free hotline. In developing the PSAs, the Integrated Behavioral Model was used as a framework to reframe negative attitudes, beliefs and norms towards HIV testing with positive ones as well as to promote self-efficacy towards HIV testing. The campaign had a significant and immediate impact on attitudes, beliefs, norms and self-efficacy towards HIV testing as well as on actual behavior, with HIV testing rates increasing over time.

  14. Examining levels of risk behaviors among black men who have sex with Men (MSM and the association with HIV acquisition.

    Directory of Open Access Journals (Sweden)

    Risha Irvin

    Full Text Available Seroadaptation is defined as the practice of modifying sexual behavior based on one's own HIV serostatus, the perceived HIV serostatus of sexual partners, and differences in risk of HIV transmission by sexual acts. Because this definition implies intent, we use the term "seroprotection" to describe HIV negative participants reporting condomless anal sex (CAS either exclusively with seronegative partners, or only as the insertive partner with HIV positive or unknown serostatus partners. Little is known about seroprotection in Black men who have sex with men (MSM. We evaluated the independent association of seroprotection and HIV acquisition among the 1144 HIV-negative Black MSM enrolled in HPTN 061 using Cox models; we stratified by city of enrollment, and controlled for number of partners, age, and drug use. Behaviors reported at 0, 6, and 12 months were assigned to three mutually exclusive categories: (1 No CAS; (2 Seroprotection; and (3 CAS without seroprotection. In 2,861 six-month intervals; 28 HIV seroconversions occurred. No CAS was reported at 33.3% of visits, seroprotection at 46.6% of visits, and CAS without seroprotection at 20.1% of visits. The seroconversion rate per 100 person-years for no CAS was 0.98 (95% CI: 0.27, 2.51, compared with 2.39 (95% CI: 1.03, 4.71 and 13.33 (95% CI: 7.62, 21.66 for seroprotection and CAS without seroprotection, respectively. Compared to CAS without seroprotection, intervals without CAS were associated with an 87% reduction (aHR: 0.13, 95% CI: 0.03-0.46 in HIV acquisition and intervals with seroprotection with a 78% reduction (aHR: 0.22, 95% CI: 0.09-0.57. No CAS is the safest behavior to prevent HIV acquisition. Seroprotective behaviors significantly reduced risk, but HIV incidence was still >2/100 person-years, suggesting that additional strategies, such as pre-exposure prophylaxis, are warranted for this population.

  15. Scene construction in developmental amnesia: an fMRI study.

    Science.gov (United States)

    Mullally, Sinéad L; Vargha-Khadem, Faraneh; Maguire, Eleanor A

    2014-01-01

    Amnesic patients with bilateral hippocampal damage sustained in adulthood are generally unable to construct scenes in their imagination. By contrast, patients with developmental amnesia (DA), where hippocampal damage was acquired early in life, have preserved performance on this task, although the reason for this sparing is unclear. One possibility is that residual function in remnant hippocampal tissue is sufficient to support basic scene construction in DA. Such a situation was found in the one amnesic patient with adult-acquired hippocampal damage (P01) who could also construct scenes. Alternatively, DA patients' scene construction might not depend on the hippocampus, perhaps being instead reliant on non-hippocampal regions and mediated by semantic knowledge. To adjudicate between these two possibilities, we examined scene construction during functional MRI (fMRI) in Jon, a well-characterised patient with DA who has previously been shown to have preserved scene construction. We found that when Jon constructed scenes he activated many of the regions known to be associated with imagining scenes in control participants including ventromedial prefrontal cortex, posterior cingulate, retrosplenial and posterior parietal cortices. Critically, however, activity was not increased in Jon's remnant hippocampal tissue. Direct comparisons with a group of control participants and patient P01, confirmed that they activated their right hippocampus more than Jon. Our results show that a type of non-hippocampal dependent scene construction is possible and occurs in DA, perhaps mediated by semantic memory, which does not appear to involve the vivid visualisation of imagined scenes. © 2013 Published by Elsevier Ltd.

  16. One high performance technology of infrared scene projection

    Science.gov (United States)

    Wang, Hong-jie; Qian, Li-xun; Cao, Chun; Li, Zhuo

    2014-11-01

    Infrared scenes generation technologies are used to simulate the infrared radiation characteristics of target and background in the laboratory. They provide synthetic infrared imagery for thermal imager test and evaluation application in the infrared imaging systems. At present, many Infrared scenes generation technologies have been widely used, and they make a lot of achievements. In this paper, we design and manufacture one high performance IR scene generation technology, and the whole thin film type transducer is the key, which is fabricated based on micro electro mechanical systems (MEMS). The specific MEMS technological process parameters are obtained from a large number of experiments. The properties of infrared scene generation chip are investigated experimentally. It achieves high resolution, high frame, and reliable performance, which can meet the requirements of most simulation system. The radiation coefficient of the thin film transducer is measured to be 0.86. The frame rate is 160 Hz. The emission spectrum is from 2μm to 12μm in infrared band. Illuminated by the visible light with different intensities the equivalent black body temperature of transducer could be varied in the range of 290K to 440K. The spatial resolution is more than 256×256.The geometric distortion and the uniformity of the generated infrared scene is 5 percent. The infrared scene generator based on the infrared scene generation chip include three parts, which are visual image projector, visual to thermal transducer and the infrared scene projector. The experimental results show that this thin film type infrared scene generation chip meets the requirements of most of hardware-in-the-loop scene simulation systems for IR sensors testing.

  17. MSM-Metal Semiconductor Metal Photo-detector Using Black Silicon Germanium (SiGe) for Extended Wavelength Near Infrared Detection

    Science.gov (United States)

    2012-09-01

    due to metal catalysis and wet etching. Using the blackened SiGe/Si, MSM photodiodes were fabricated and tested. The lowering of reflection using a...MSM- Metal Semiconductor Metal Photo-detector Using Black Silicon Germanium (SiGe) for Extended Wavelength Near Infrared Detection by Fred...Do not return it to the originator. Army Research Laboratory Adelphi, MD 20783-1197 ARL-TR-6176 September 2012 MSM- Metal

  18. Hierarchical 3D structural matching in aerospace photographs and indoor scenes

    Science.gov (United States)

    Lutsiv, Vadim; Potapov, Alexey; Novikova, Tatiana; Lapina, Nina

    2005-05-01

    The investigation presented in this article continues our long-term efforts directed towards the automatic structural matching of aerospace photographs. An efficient target independent hierarchical structural matching tool was described in our previous paper, which, however, was aimed mostly for the analysis of 2D scenes. It applied the same geometric transformation model to the whole area of image, thus it was nice for the space photographs taken from rather high orbits, but it often failed in the cases when the sensors were positioned near the 3D scenes being observed. Different transformation models should be applied to different parts of images in the last case, and finding a correct separation of image into the areas of homogeneous geometric transformations was the main problem. Now we succeeded in separating the images of scenes into the surfaces of different objects on the base of their textural and spectral features, thus we have got a possibility of separate matching the sub-images corresponding to such objects applying different transformation model to each such sub-image. Some additional limitations were used in the course of such separation and matching. In particular, the a priory assumptions were applied in different cases about the possible geometry of scenes, rules of illumination and shadowing, thus the aerospace photographs, indoor scenes, or images of aircrafts were analyzed in slightly differing ways. However the additional limitations applied could be considered as very general and are worth to be used in a wide sphere of practical tasks. The automatic image analysis was successful in all considered practical cases.

  19. The role of distress intolerance in the relationship between childhood sexual abuse and problematic alcohol use among Latin American MSM.

    Science.gov (United States)

    Wang, Katie; White Hughto, Jaclyn M; Biello, Katie B; O'Cleirigh, Conall; Mayer, Kenneth H; Rosenberger, Joshua G; Novak, David S; Mimiaga, Matthew J

    2017-06-01

    Despite the high prevalence of childhood sexual abuse (CSA) among men who have sex with men (MSM) and its well-documented association with substance use in adulthood, little research has examined the psychological mechanisms underlying this association. The current study utilized a large, multinational sample of MSM in Latin America to examine the role of distress intolerance (i.e., decreased capacity to withstand negative psychological states) in the relationship between childhood sexual abuse history and problematic alcohol use. As part of an online survey conducted among members of the largest social/sexual networking website for MSM in Latin America, participants (n=19,451) completed measures of childhood sexual abuse history, distress intolerance, and problematic alcohol use (CAGE score>=2). Participants who reported a history of childhood sexual abuse indicated higher levels of distress intolerance, which was in turn associated with greater odds of engaging in problematic alcohol use. A mediation analysis further showed that distress intolerance partially accounted for the significant association between childhood sexual abuse history and problematic alcohol use. These findings provide initial evidence for the role of distress intolerance as a process through which early trauma shapes MSM health later in life. These findings also underscore the potential utility of addressing distress intolerance in alcohol use prevention and intervention efforts that target MSM with a history of childhood sexual abuse. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. Art Toys in the contemporary art scene

    Directory of Open Access Journals (Sweden)

    Laura Sernissi

    2014-03-01

    Full Text Available The Art Toys phenomenon, better known as Art Toy Movement, was born in China in the mid-nineties and quickly spread out to the rest of the world. The toys are an artistic production of serial sculpture, made by handcrafts or on an industrial scale. There are several types of toys, such as custom toys and canvas toys, synonyms of designer toys, although they are often defined according to the constituent material, such as vinyl toys (plastic and plush toys (fabric. Art toys are the heirs of an already pop-surrealist and neo-pop circuit, which since the eighties of the twentieth century has pervaded the Japanese-American art scene, winking to the playful spirit of the avant-garde of the early century. Some psychoanalytic, pedagogical and anthropological studies about “play theories”, may also help us to understand and identify these heterogeneous products as real works of art and not simply as collectible toys.

  1. Crime scene investigation (as seen on TV).

    Science.gov (United States)

    Durnal, Evan W

    2010-06-15

    A mysterious green ooze is injected into a brightly illuminated and humming machine; 10s later, a printout containing a complete biography of the substance is at the fingertips of an attractive young investigator who exclaims "we found it!" We have all seen this event occur countless times on any and all of the three CSI dramas, Cold Cases, Crossing Jordans, and many more. With this new style of "infotainment" (Surette, 2007), comes an increasingly blurred line between the hard facts of reality and the soft, quick solutions of entertainment. With these advances in technology, how can crime rates be anything but plummeting as would-be criminals cringe at the idea of leaving the smallest speck of themselves at a crime scene? Surely there are very few serious crimes that go unpunished in today's world of high-tech, fast-paced gadgetry. Science and technology have come a great distance since Sir Arthur Conan Doyle first described the first famous forensic scientist (Sherlock Holmes), but still have light-years to go. (c) 2010. Published by Elsevier Ireland Ltd.

  2. Medical Monitoring During Firefighter Incident Scene Rehabilitation.

    Science.gov (United States)

    Barr, David A; Haigh, Craig A; Haller, Jeannie M; Smith, Denise L

    2016-01-01

    The objective of this study was to retrospectively investigate aspects of medical monitoring, including medical complaints, vital signs at entry, and vital sign recovery, in firefighters during rehabilitation following operational firefighting duties. Incident scene rehabilitation logs obtained over a 5-year span that included 53 incidents, approximately 40 fire departments, and more than 530 firefighters were reviewed. Only 13 of 694 cases involved a firefighter reporting a medical complaint. In most cases, vital signs were similar between firefighters who registered a complaint and those who did not. On average, heart rate was 104 ± 23 beats·min(-1), systolic blood pressure was 132 ± 17 mmHg, diastolic blood pressure was 81 ± 12 mmHg, and respiratory rate was 19 ± 3 breaths·min(-1) upon entry into rehabilitation. At least two measurements of heart rate, systolic blood pressure, diastolic blood pressure, and respiratory rate were obtained for 365, 383, 376, and 160 cases, respectively. Heart rate, systolic and diastolic blood pressures, and respiratory rate decreased significantly (p firefighters recovered from the physiological stress of firefighting without any medical complaint or symptoms. Furthermore, vital signs were within fire service suggested guidelines for release within 10 or 20 minutes of rehabilitation. The data suggested that vital signs of firefighters with medical symptoms were not significantly different from vital signs of firefighters who had an unremarkable recovery.

  3. Scan patterns during real-world scene viewing predict individual differences in cognitive capacity.

    Science.gov (United States)

    Hayes, Taylor R; Henderson, John M

    2017-05-01

    From the earliest recordings of eye movements during active scene viewing to the present day, researchers have commonly reported individual differences in eye movement scan patterns under constant stimulus and task demands. These findings suggest viewer individual differences may be important for understanding gaze control during scene viewing. However, the relationship between scan patterns and viewer individual differences during scene viewing remains poorly understood because scan patterns are difficult to analyze. The present study uses a powerful technique called Successor Representation Scanpath Analysis (Hayes, Petrov, & Sederberg, 2011, 2015) to quantify the strength of the association between individual differences in scan patterns during real-world scene viewing and individual differences in viewer intelligence, working memory capacity, and speed of processing. The results of this analysis revealed individual differences in scan patterns that explained more than 40% of the variance in viewer intelligence and working memory capacity measures, and more than a third of the variance in speed of processing measures. The theoretical implications of our findings for models of gaze control and avenues for future individual differences research are discussed.

  4. -The Influence of Scene Context on Parafoveal Processing of Objects.

    Science.gov (United States)

    Castelhano, Monica S; Pereira, Effie J

    2017-04-21

    Many studies in reading have shown the enhancing effect of context on the processing of a word before it is directly fixated (parafoveal processing of words; Balota et al., 1985; Balota & Rayner, 1983; Ehrlich & Rayner, 1981). Here, we examined whether scene context influences the parafoveal processing of objects and enhances the extraction of object information. Using a modified boundary paradigm (Rayner, 1975), the Dot-Boundary paradigm, participants fixated on a suddenly-onsetting cue before the preview object would onset 4° away. The preview object could be identical to the target, visually similar, visually dissimilar, or a control (black rectangle). The preview changed to the target object once a saccade toward the object was made. Critically, the objects were presented on either a consistent or an inconsistent scene background. Results revealed that there was a greater processing benefit for consistent than inconsistent scene backgrounds and that identical and visually similar previews produced greater processing benefits than other previews. In the second experiment, we added an additional context condition in which the target location was inconsistent, but the scene semantics remained consistent. We found that changing the location of the target object disrupted the processing benefit derived from the consistent context. Most importantly, across both experiments, the effect of preview was not enhanced by scene context. Thus, preview information and scene context appear to independently boost the parafoveal processing of objects without any interaction from object-scene congruency.

  5. A Method of Sharing Tacit Knowledge by a Bulletin Board Link to Video Scene and an Evaluation in the Field of Nursing Skill

    Science.gov (United States)

    Shimada, Satoshi; Azuma, Shouzou; Teranaka, Sayaka; Kojima, Akira; Majima, Yukie; Maekawa, Yasuko

    We developed the system that knowledge could be discovered and shared cooperatively in the organization based on the SECI model of knowledge management. This system realized three processes by the following method. (1)A video that expressed skill is segmented into a number of scenes according to its contents. Tacit knowledge is shared in each scene. (2)Tacit knowledge is extracted by bulletin board linked to each scene. (3)Knowledge is acquired by repeatedly viewing the video scene with the comment that shows the technical content to be practiced. We conducted experiments that the system was used by nurses working for general hospitals. Experimental results show that the nursing practical knack is able to be collected by utilizing bulletin board linked to video scene. Results of this study confirmed the possibility of expressing the tacit knowledge of nurses' empirical nursing skills sensitively with a clue of video images.

  6. Three-dimensional measurement system for crime scene documentation

    Science.gov (United States)

    Adamczyk, Marcin; Hołowko, Elwira; Lech, Krzysztof; Michoński, Jakub; MÄ czkowski, Grzegorz; Bolewicki, Paweł; Januszkiewicz, Kamil; Sitnik, Robert

    2017-10-01

    Three dimensional measurements (such as photogrammetry, Time of Flight, Structure from Motion or Structured Light techniques) are becoming a standard in the crime scene documentation process. The usage of 3D measurement techniques provide an opportunity to prepare more insightful investigation and helps to show every trace in the context of the entire crime scene. In this paper we would like to present a hierarchical, three-dimensional measurement system that is designed for crime scenes documentation process. Our system reflects the actual standards in crime scene documentation process - it is designed to perform measurement in two stages. First stage of documentation, the most general, is prepared with a scanner with relatively low spatial resolution but also big measuring volume - it is used for the whole scene documentation. Second stage is much more detailed: high resolution but smaller size of measuring volume for areas that required more detailed approach. The documentation process is supervised by a specialised application CrimeView3D, that is a software platform for measurements management (connecting with scanners and carrying out measurements, automatic or semi-automatic data registration in the real time) and data visualisation (3D visualisation of documented scenes). It also provides a series of useful tools for forensic technicians: virtual measuring tape, searching for sources of blood spatter, virtual walk on the crime scene and many others. In this paper we present our measuring system and the developed software. We also provide an outcome from research on metrological validation of scanners that was performed according to VDI/VDE standard. We present a CrimeView3D - a software-platform that was developed to manage the crime scene documentation process. We also present an outcome from measurement sessions that were conducted on real crime scenes with cooperation with Technicians from Central Forensic Laboratory of Police.

  7. Differences Between Men Who Have Sex with Men (MSM) with Low CD4 Cell Counts at Their First HIV Test and MSM with Higher CD4 Counts in Bangkok, Thailand.

    Science.gov (United States)

    Sapsirisavat, Vorapot; Phanuphak, Nittaya; Sophonphan, Jiratchaya; Egan, James E; Langevattana, Kamonthip; Avihingsanon, Anchalee; Friedman, M Reuel; Stall, Ron

    2016-12-01

    Although HIV prevalence remains high among Bangkok's MSM early HIV testing as an entry point to ART has not been successfully implemented among in this population. Men who present late for initial HIV testing are a particular concern in the context of the Bangkok HIV epidemic, in that if long-term positives have had condomless sex during the time that they remained untreated they are likely to have been efficient transmitters of infection, to say nothing of the implications for their own health. A sequential sample of MSM who tested HIV positive, and CD4 counts, was taken at the Thai Red Cross Anonymous Clinic and two drop-in centers in Bangkok. Inclusion criteria were MSM aged >18 years, having not tested HIV positive earlier, who reported ≥1 of the following in the previous 6 months: condomless sex with a male, being a sex worker, or having a sexual transmitted infection (STI) diagnosis. Analysis was conducted by distinguishing between three groups of CD4 counts: 500 cells/μ to identify the social and behavioral characteristics of the men who presented late for HIV testing. Median CD4 was 325 cells/μ(n = 95). MSM with initial CD4work. MSM with CD4HIV testing. Main barriers to HIV testing included being afraid of finding out that they were HIV positive and concerns about efficacy and side effects of HIV treatment. HIV stigma and concerns about treatment are still widespread and are potential barriers to HIV care among MSM in Bangkok. These barriers may work to keep men from finding out their positive HIV status in a timely manner. Thai MSM need to be made aware of the current availability of friendly HIV testing and ART services, and public health programs need to work to change their perceptions regarding ART itself. These same types of strategies might also work to destigmatize HIV and MSM within Thai society as a whole.

  8. Psycho-social Correlates of Condom Use and HIV Testing among MSM Refugees in Beirut, Lebanon.

    Science.gov (United States)

    Tohme, Johnny; Egan, James E; Friedman, Mackey R; Stall, Ron

    2016-12-01

    MSM refugees have to deal with personal challenges and social/structural adversaries based on their refugee status on top of their sexual identity. To better customize interventions beside this population, we explored psycho-social and structural correlates of condom use and HIV testing in Lebanon by surveying and testing 150 participants. 67 % self-identified as gay. 84.6 % reported any unprotected anal intercourse (UAI) with men in the prior 3 months. Those who engaged in UAI, were lest comfortable with a doctor, didn't know where to get free HIV testing, experienced discrimination based on their refugee status and spent more time with their refugee peers, were less inclined to have seen a doctor in the past 12 month or knew where to get free HIV testing. Ever having been HIV tested was associated with being comfortable with medical doctors, knowing where to get HIV testing and spending time with other peer refugees. HIV prevention and testing promotion efforts targeting MSM refugees need to account for structural barriers, while fighting discrimination is crucial for a healthy sexual identity development.

  9. HIV testing practices of South African township MSM in the era of expanded access to ART.

    Science.gov (United States)

    Sandfort, Theo G M; Knox, Justin; Collier, Kate L; Lane, Tim; Reddy, Vasu

    2015-03-01

    While men who have sex with men (MSM) in Africa are at high risk for HIV infection, few of those already infected know their status. Effectively promoting frequent HIV testing-of increasing importance with the expanding accessibility of antiretroviral treatment-requires an understanding of the testing practices in this population. To understand men's HIV testing practices, including their behavior, experiences, and perceptions, we conducted in-depth interviews with 81 black South African MSM (ages 20-39), purposively recruited from four townships. Many men in the sample had tested for HIV. While ever having tested seemed to facilitate repeat testing, men still expressed a high level of discomfort with testing. It was common to test after having engaged in risky behavior, thus increasing anxiety about testing that was already present. Fear that they might test HIV positive caused some men to avoid testing until they were clearly sick, and others to avoid testing completely. HIV testing may increase in this population if it becomes a routine practice, instead of being driven by anxiety-inducing incidents. Mobilization through social support might facilitate frequent testing while education about current treatment options is needed.

  10. Application of the Modified Source Multiplication (MSM) Technique to Subcritical Reactivity Worth Measurements in Thermal and Fast Reactor Systems

    Science.gov (United States)

    Blaise, Patrick; Mellier, Frédéric; Fougeras, Philippe

    2011-06-01

    The Amplified Source Multiplication (ASM) method and its improved Modified Source Multiplication (MSM) method have been widely used in the CEA's EOLE and MASURCA critical facilities over the past decades for the determination of reactivity worths by using fission chambers in subcritical configurations. The ASM methodology uses relatively simple relationships between count rates of efficient miniature fission chambers located in slightly subcritical reference and perturbed configurations. While this method works quite well for small reactivity variations, the raw results need to be corrected to take into account the flux perturbation at the fission chamber location. This is performed by applying to the measurement a correction factor called MSM. This paper describes in detail both methodologies, with their associated uncertainties. Applications on absorber cluster worth in the MISTRAL-4 full MOX mock-up core and the last core loaded in MASURCA show the importance of the MSM correction on raw ASM data.

  11. Potential impact on HIV incidence of higher HIV testing rates and earlier antiretroviral therapy initiation in MSM

    DEFF Research Database (Denmark)

    Phillips, Andrew N; Cambiano, Valentina; Miners, Alec

    2015-01-01

    BACKGROUND: Increased rates of testing, with early antiretroviral therapy (ART) initiation, represent a key potential HIV-prevention approach. Currently, in MSM in the United Kingdom, it is estimated that 36% are diagnosed by 1 year from infection, and the ART initiation threshold is at CD4 cell...... count 350/μl. We investigated what would be required to reduce HIV incidence in MSM to below 1 per 1000 person-years (i.e. ... on HIV in MSM in the United Kingdom. Outcomes were projected according to future alternative HIV testing and ART initiation scenarios to 2030, considering also potential changes in levels of condomless sex. RESULTS: For ART use to result in an incidence of close to 1/1000 person-years requires...

  12. Intrinsic Scene Decomposition from RGB-D Images

    KAUST Repository

    Hachama, Mohammed

    2015-12-07

    In this paper, we address the problem of computing an intrinsic decomposition of the colors of a surface into an albedo and a shading term. The surface is reconstructed from a single or multiple RGB-D images of a static scene obtained from different views. We thereby extend and improve existing works in the area of intrinsic image decomposition. In a variational framework, we formulate the problem as a minimization of an energy composed of two terms: a data term and a regularity term. The first term is related to the image formation process and expresses the relation between the albedo, the surface normals, and the incident illumination. We use an affine shading model, a combination of a Lambertian model, and an ambient lighting term. This model is relevant for Lambertian surfaces. When available, multiple views can be used to handle view-dependent non-Lambertian reflections. The second term contains an efficient combination of l2 and l1-regularizers on the illumination vector field and albedo respectively. Unlike most previous approaches, especially Retinex-like techniques, these terms do not depend on the image gradient or texture, thus reducing the mixing shading/reflectance artifacts and leading to better results. The obtained non-linear optimization problem is efficiently solved using a cyclic block coordinate descent algorithm. Our method outperforms a range of state-of-the-art algorithms on a popular benchmark dataset.

  13. Fitting boxes to Manhattan scenes using linear integer programming

    KAUST Repository

    Li, Minglei

    2016-02-19

    We propose an approach for automatic generation of building models by assembling a set of boxes using a Manhattan-world assumption. The method first aligns the point cloud with a per-building local coordinate system, and then fits axis-aligned planes to the point cloud through an iterative regularization process. The refined planes partition the space of the data into a series of compact cubic cells (candidate boxes) spanning the entire 3D space of the input data. We then choose to approximate the target building by the assembly of a subset of these candidate boxes using a binary linear programming formulation. The objective function is designed to maximize the point cloud coverage and the compactness of the final model. Finally, all selected boxes are merged into a lightweight polygonal mesh model, which is suitable for interactive visualization of large scale urban scenes. Experimental results and a comparison with state-of-the-art methods demonstrate the effectiveness of the proposed framework.

  14. Embryo disposition and the new death scene

    Directory of Open Access Journals (Sweden)

    Ellison, David

    2011-01-01

    Full Text Available In the IVF clinic - a place designed principally for the production and implantation of embryos - scientists and IVF recipients are faced with decisions regarding the disposition of frozen embryos. At this time there are hundred of thousands of cryopreserved embryos awaiting such determinations. They may be thawed for transfer to the woman herself, they may be donated for research or for use by other infertile couples, they may remain in frozen storage, or they may variously be discarded by being allowed to 'succumb', or 'perish'. Where the choice is discard, some IVF clients have chosen to formalise the process through ceremony. A new language is emerging in response to the desires of the would-be-parents who might wish to characterise the discard experience as a ‘good death’. This article examines the procedure known as ‘compassionate transfer’ where the embryo to be discarded is placed in the woman’s vagina where it is clear that it will not develop further. An alternate method has the embryo transferred in the usual manner but without the benefit of fertility-enhancing hormones at a point in the cycle unreceptive to implantation. The embryo destined for disposal is thus removed from the realm of technological possibility and ‘returned’ to the female body for a homely death. While debates continue about whether or not embryos constitute life, new practices are developing in response to the emotional experience of embryo discard. We argue that compassionate transfer is a death scene taking shape. In this article, we take the measure of this new death scene’s fabrication, and consider the form, significance, and legal complexity of its ceremonies.

  15. Illicit drug use among gay and bisexual men in 44 cities: Findings from the European MSM Internet Survey (EMIS).

    Science.gov (United States)

    Schmidt, Axel J; Bourne, Adam; Weatherburn, Peter; Reid, David; Marcus, Ulrich; Hickson, Ford

    2016-12-01

    Anecdotal evidence suggests that men who have sex with men (MSM) are increasingly combining sex and illicit drugs (an activity referred to as 'chemsex'), in particular GHB/GBL, ketamine, crystal meth, or mephedrone (here called 4-chems). Use of such drugs has been associated with mental health and sexual health harms. We aim to compare patterns of illicit drug use among MSM in 44 European urban centres. In 2010, EMIS recruited 174,209 men from 38 countries to an anonymous online questionnaire in 25 languages. As harm reduction services for drugs and sex are organised at a local level, we chose to compare cities rather than countries. We defined 44 cities based on region/postal code and settlement size. For multivariable regression analyses, three comparison groups of MSM not living in these cities were applied: MSM living in Germany, the UK, and elsewhere in Europe. Data from 55,446 MSM living in 44 urban centres were included. Use of 4-chems (past 4 weeks) was highest in Brighton (16.3%), Manchester (15.5%), London (13.2%), Amsterdam (11.2%), Barcelona (7.9%), Zurich (7.0%) and Berlin (5.3%). It was lowest in Sofia (0.4%). The rank order was largely consistent when controlling for age, HIV diagnosis, and number of sexual partners. City of residence was the strongest demographic predictor of chemsex-drug use. Use of drugs associated with chemsex among MSM varies substantially across European cities. As city is the strongest predictor of chemsex-drug use, effective harm reduction programmes must include structural as well as individual interventions. Copyright © 2016 Elsevier B.V. All rights reserved.

  16. Traffic Command Gesture Recognition for Virtual Urban Scenes Based on a Spatiotemporal Convolution Neural Network

    Directory of Open Access Journals (Sweden)

    Chunyong Ma

    2018-01-01

    Full Text Available Intelligent recognition of traffic police command gestures increases authenticity and interactivity in virtual urban scenes. To actualize real-time traffic gesture recognition, a novel spatiotemporal convolution neural network (ST-CNN model is presented. We utilized Kinect 2.0 to construct a traffic police command gesture skeleton (TPCGS dataset collected from 10 volunteers. Subsequently, convolution operations on the locational change of each skeletal point were performed to extract temporal features, analyze the relative positions of skeletal points, and extract spatial features. After temporal and spatial features based on the three-dimensional positional information of traffic police skeleton points were extracted, the ST-CNN model classified positional information into eight types of Chinese traffic police gestures. The test accuracy of the ST-CNN model was 96.67%. In addition, a virtual urban traffic scene in which real-time command tests were carried out was set up, and a real-time test accuracy rate of 93.0% was achieved. The proposed ST-CNN model ensured a high level of accuracy and robustness. The ST-CNN model recognized traffic command gestures, and such recognition was found to control vehicles in virtual traffic environments, which enriches the interactive mode of the virtual city scene. Traffic command gesture recognition contributes to smart city construction.

  17. Hybrid infrared scene projector (HIRSP): a high dynamic range infrared scene projector, part II

    Science.gov (United States)

    Cantey, Thomas M.; Bowden, Mark; Cosby, David; Ballard, Gary

    2008-04-01

    This paper is a continuation of the merging of two dynamic infrared scene projector technologies to provide a unique and innovative solution for the simulation of high dynamic temperature ranges for testing infrared imaging sensors. This paper will present some of the challenges and performance issues encountered in implementing this unique projector system into a Hardware-in-the-Loop (HWIL) simulation facility. The projection system combines the technologies of a Honeywell BRITE II extended voltage range emissive resistor array device and an optically scanned laser diode array projector (LDAP). The high apparent temperature simulations are produced from the luminescent infrared radiation emitted by the high power laser diodes. The hybrid infrared projector system is being integrated into an existing HWIL simulation facility and is used to provide real-world high radiance imagery to an imaging infrared unit under test. The performance and operation of the projector is presented demonstrating the merit and success of the hybrid approach. The high dynamic range capability simulates a 250 Kelvin apparent background temperature to 850 Kelvin maximum apparent temperature signatures. This is a large increase in radiance projection over current infrared scene projection capabilities.

  18. Attention in natural scenes: Affective-motivational factors guide gaze independently of visual salience.

    Science.gov (United States)

    Schomaker, Judith; Walper, Daniel; Wittmann, Bianca C; Einhäuser, Wolfgang

    2017-04-01

    In addition to low-level stimulus characteristics and current goals, our previous experience with stimuli can also guide attentional deployment. It remains unclear, however, if such effects act independently or whether they interact in guiding attention. In the current study, we presented natural scenes including every-day objects that differed in affective-motivational impact. In the first free-viewing experiment, we presented visually-matched triads of scenes in which one critical object was replaced that varied mainly in terms of motivational value, but also in terms of valence and arousal, as confirmed by ratings by a large set of observers. Treating motivation as a categorical factor, we found that it affected gaze. A linear-effect model showed that arousal, valence, and motivation predicted fixations above and beyond visual characteristics, like object size, eccentricity, or visual salience. In a second experiment, we experimentally investigated whether the effects of emotion and motivation could be modulated by visual salience. In a medium-salience condition, we presented the same unmodified scenes as in the first experiment. In a high-salience condition, we retained the saturation of the critical object in the scene, and decreased the saturation of the background, and in a low-salience condition, we desaturated the critical object while retaining the original saturation of the background. We found that highly salient objects guided gaze, but still found additional additive effects of arousal, valence and motivation, confirming that higher-level factors can also guide attention, as measured by fixations towards objects in natural scenes. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Transferring Deep Convolutional Neural Networks for the Scene Classification of High-Resolution Remote Sensing Imagery

    Directory of Open Access Journals (Sweden)

    Fan Hu

    2015-11-01

    Full Text Available Learning efficient image representations is at the core of the scene classification task of remote sensing imagery. The existing methods for solving the scene classification task, based on either feature coding approaches with low-level hand-engineered features or unsupervised feature learning, can only generate mid-level image features with limited representative ability, which essentially prevents them from achieving better performance. Recently, the deep convolutional neural networks (CNNs, which are hierarchical architectures trained on large-scale datasets, have shown astounding performance in object recognition and detection. However, it is still not clear how to use these deep convolutional neural networks for high-resolution remote sensing (HRRS scene classification. In this paper, we investigate how to transfer features from these successfully pre-trained CNNs for HRRS scene classification. We propose two scenarios for generating image features via extracting CNN features from different layers. In the first scenario, the activation vectors extracted from fully-connected layers are regarded as the final image features; in the second scenario, we extract dense features from the last convolutional layer at multiple scales and then encode the dense features into global image features through commonly used feature coding approaches. Extensive experiments on two public scene classification datasets demonstrate that the image features obtained by the two proposed scenarios, even with a simple linear classifier, can result in remarkable performance and improve the state-of-the-art by a significant margin. The results reveal that the features from pre-trained CNNs generalize well to HRRS datasets and are more expressive than the low- and mid-level features. Moreover, we tentatively combine features extracted from different CNN models for better performance.

  20. Earth Virtual-Environment Immersive Scene Display System Project

    Data.gov (United States)

    National Aeronautics and Space Administration — In response to the NASA need for a free-standing immersive virtual scene display system interfaced with an exercise treadmill to mimic terrestrial exercise...

  1. The influence of color on emotional perception of natural scenes.

    Science.gov (United States)

    Codispoti, Maurizio; De Cesarei, Andrea; Ferrari, Vera

    2012-01-01

    Is color a critical factor when processing the emotional content of natural scenes? Under challenging perceptual conditions, such as when pictures are briefly presented, color might facilitate scene segmentation and/or function as a semantic cue via association with scene-relevant concepts (e.g., red and blood/injury). To clarify the influence of color on affective picture perception, we compared the late positive potentials (LPP) to color versus grayscale pictures, presented for very brief (24 ms) and longer (6 s) exposure durations. Results indicated that removing color information had no effect on the affective modulation of the LPP, regardless of exposure duration. These findings imply that the recognition of the emotional content of scenes, even when presented very briefly, does not critically rely on color information. Copyright © 2011 Society for Psychophysiological Research.

  2. Big visual data analysis scene classification and geometric labeling

    CERN Document Server

    Chen, Chen; Kuo, C -C Jay

    2016-01-01

    This book offers an overview of traditional big visual data analysis approaches and provides state-of-the-art solutions for several scene comprehension problems, indoor/outdoor classification, outdoor scene classification, and outdoor scene layout estimation. It is illustrated with numerous natural and synthetic color images, and extensive statistical analysis is provided to help readers visualize big visual data distribution and the associated problems. Although there has been some research on big visual data analysis, little work has been published on big image data distribution analysis using the modern statistical approach described in this book. By presenting a complete methodology on big visual data analysis with three illustrative scene comprehension problems, it provides a generic framework that can be applied to other big visual data analysis tasks.

  3. Scene construction in developmental amnesia: An fMRI study

    OpenAIRE

    Mullally, Sinéad L.; Vargha-Khadem, Faraneh; Maguire, Eleanor A.

    2014-01-01

    Amnesic patients with bilateral hippocampal damage sustained in adulthood are generally unable to construct scenes in their imagination. By contrast, patients with developmental amnesia (DA), where hippocampal damage was acquired early in life, have preserved performance on this task, although the reason for this sparing is unclear. One possibility is that residual function in remnant hippocampal tissue is sufficient to support basic scene construction in DA. Such a situation was found in the...

  4. Online anomaly detection in crowd scenes via structure analysis.

    Science.gov (United States)

    Yuan, Yuan; Fang, Jianwu; Wang, Qi

    2015-03-01

    Abnormal behavior detection in crowd scenes is continuously a challenge in the field of computer vision. For tackling this problem, this paper starts from a novel structure modeling of crowd behavior. We first propose an informative structural context descriptor (SCD) for describing the crowd individual, which originally introduces the potential energy function of particle's interforce in solid-state physics to intuitively conduct vision contextual cueing. For computing the crowd SCD variation effectively, we then design a robust multi-object tracker to associate the targets in different frames, which employs the incremental analytical ability of the 3-D discrete cosine transform (DCT). By online spatial-temporal analyzing the SCD variation of the crowd, the abnormality is finally localized. Our contribution mainly lies on three aspects: 1) the new exploration of abnormal detection from structure modeling where the motion difference between individuals is computed by a novel selective histogram of optical flow that makes the proposed method can deal with more kinds of anomalies; 2) the SCD description that can effectively represent the relationship among the individuals; and 3) the 3-D DCT multi-object tracker that can robustly associate the limited number of (instead of all) targets which makes the tracking analysis in high density crowd situation feasible. Experimental results on several publicly available crowd video datasets verify the effectiveness of the proposed method.

  5. Willingness of men who have sex with men (MSM in the United States to be circumcised as adults to reduce the risk of HIV infection.

    Directory of Open Access Journals (Sweden)

    Elin B Begley

    Full Text Available BACKGROUND: Circumcision reduces HIV acquisition among heterosexual men in Africa, but it is unclear if circumcision may reduce HIV acquisition among men who have sex with men (MSM in the United States, or whether MSM would be willing to be circumcised if recommended. METHODS: We interviewed presumed-HIV negative MSM at gay pride events in 2006. We asked uncircumcised respondents about willingness to be circumcised if it were proven to reduce risk of HIV among MSM and perceived barriers to circumcision. Multivariate logistic regression was used to identify covariates associated with willingness to be circumcised. RESULTS: Of 780 MSM, 133 (17% were uncircumcised. Of these, 71 (53% were willing to be circumcised. Willingness was associated with black race (exact odds ratio [OR]: 3.4, 95% confidence interval [CI]: 1.3-9.8, non-injection drug use (OR: 6.1, 95% CI: 1.8-23.7 and perceived reduced risk of penile cancer (OR: 4.7, 95% CI: 2.0-11.9. The most commonly endorsed concerns about circumcision were post-surgical pain and wound infection. CONCLUSIONS: Over half of uncircumcised MSM, especially black MSM, expressed willingness to be circumcised. Perceived risks and benefits of circumcision should be a part of educational materials if circumcision is recommended for MSM in the United States.

  6. Demographic and Behavioral Determinants of Self-Reported History of Sexually-Transmitted Diseases (STDs) among Young Migrant Men Who Have Sex with Men (MSM) in Beijing, China

    Science.gov (United States)

    Song, Yan; Li, Xiaoming; Zhang, Liying; Liu, Yingjie; Jiang, Shulin; Stanton, Bonita

    2012-01-01

    Background: Sexually-transmitted disease (STD) is a facilitating cofactor that contributes to human immunodeficiency virus (HIV) transmission. Previous studies indicated a high prevalence of STDs among men who have sex with men (MSM) in China. To date, limited data are available for correlates of STD infection among young migrant MSM in China. The…

  7. Limited overlap between phylogenetic HIV and hepatitis C virus clusters illustrates the dynamic sexual network structure of Dutch HIV-infected MSM

    NARCIS (Netherlands)

    Vanhommerig, Joost W.; Bezemer, Daniela; Molenkamp, Richard; van Sighem, Ard I.; Smit, Colette; Arends, Joop E.; Lauw, Fanny N.; Brinkman, Kees; Rijnders, Bart J.; Newsum, Astrid M.; Bruisten, Sylvia M.; Prins, Maria; van der Meer, Jan T.; van de Laar, Thijs J.; Schinkel, Janke

    2017-01-01

    Objective: MSM are at increased risk for infection with HIV-1 and hepatitis C virus (HCV). Is HIV/HCV coinfection confined to specific HIV transmission networks? Design and methods: A HIV phylogenetic tree was constructed for 5038 HIV-1 subtype B polymerase (pol) sequences obtained from MSM in the

  8. Crime Scene Reconstruction Using a Fully Geomatic Approach

    Directory of Open Access Journals (Sweden)

    Andrea Lingua

    2008-10-01

    Full Text Available This paper is focused on two main topics: crime scene reconstruction, based on a geomatic approach, and crime scene analysis, through GIS based procedures. According to the experience of the authors in performing forensic analysis for real cases, the aforesaid topics will be examined with the specific goal of verifying the relationship of human walk paths at a crime scene with blood patterns on the floor. In order to perform such analyses, the availability of pictures taken by first aiders is mandatory, since they provide information about the crime scene before items are moved or interfered with. Generally, those pictures are affected by large geometric distortions, thus - after a brief description of the geomatic techniques suitable for the acquisition of reference data (total station surveying, photogrammetry and laser scanning - it will be shown the developed methodology, based on photogrammetric algorithms, aimed at calibrating, georeferencing and mosaicking the available images acquired on the scene. The crime scene analysis is based on a collection of GIS functionalities for simulating human walk movements and creating a statistically significant sample. The developed GIS software component will be described in detail, showing how the analysis of this statistical sample of simulated human walks allows to rigorously define the probability of performing a certain walk path without touching the bloodstains on the floor.

  9. EigenScape: A Database of Spatial Acoustic Scene Recordings

    Directory of Open Access Journals (Sweden)

    Marc Ciufo Green

    2017-11-01

    Full Text Available The classification of acoustic scenes and events is an emerging area of research in the field of machine listening. Most of the research conducted so far uses spectral features extracted from monaural or stereophonic audio rather than spatial features extracted from multichannel recordings. This is partly due to the lack thus far of a substantial body of spatial recordings of acoustic scenes. This paper formally introduces EigenScape, a new database of fourth-order Ambisonic recordings of eight different acoustic scene classes. The potential applications of a spatial machine listening system are discussed before detailed information on the recording process and dataset are provided. A baseline spatial classification system using directional audio coding (DirAC techniques is detailed and results from this classifier are presented. The classifier is shown to give good overall scene classification accuracy across the dataset, with 7 of 8 scenes being classified with an accuracy of greater than 60% with an 11% improvement in overall accuracy compared to use of Mel-frequency cepstral coefficient (MFCC features. Further analysis of the results shows potential improvements to the classifier. It is concluded that the results validate the new database and show that spatial features can characterise acoustic scenes and as such are worthy of further investigation.

  10. Separating reflective and fluorescent components for dynamic scenes

    Science.gov (United States)

    Ji, Xiangyang; Miao, Changlong; Zhang, Yongbing; Lin, Xing; Dai, Qionghai

    2017-12-01

    Separating reflective and fluorescent components by hyperspectral (HS) imaging is significant in many applications. This paper designs an imaging system, where both HS reflective images and HS fluorescent images could be obtained from the same scene, even scenes within moving objects. The system consists of a high-frequency-spectra light source and a spatially-spectrally encoded camera. During the capture phase, the light source illuminates the scene with two high-frequency lighting patterns complemented in the spectral domain by turns, then encoded camera captures a image pair accordingly. During the reconstruction phase, sparsity of the natural reflective and fluorescent HS images is utilized to recover reflective and fluorescent spectra from encoded image pair. Benefited from double-shot imaging system, dynamic scene could also be handled. The method is tested in various datasets(including synthetic and real data), and the results demonstrate that the system could achieve high-resolution hyperspectral reflectance and fluorescence recovery with high-accuracy for dynamic scenes, which can be applied for spectral relighting of real scenes.

  11. Scene Text Detection and Segmentation based on Cascaded Convolution Neural Networks.

    Science.gov (United States)

    Tang, Youbao; Wu, Xiangqian

    2017-01-20

    Scene text detection and segmentation are two important and challenging research problems in the field of computer vision. This paper proposes a novel method for scene text detection and segmentation based on cascaded convolution neural networks (CNNs). In this method, a CNN based text-aware candidate text region (CTR) extraction model (named detection network, DNet) is designed and trained using both the edges and the whole regions of text, with which coarse CTRs are detected. A CNN based CTR refinement model (named segmentation network, SNet) is then constructed to precisely segment the coarse CTRs into text to get the refined CTRs. With DNet and SNet, much fewer CTRs are extracted than with traditional approaches while more true text regions are kept. The refined CTRs are finally classified using a CNN based CTR classification model (named classification network, CNet) to get the final text regions. All of these CNN based models are modified from VGGNet-16. Extensive experiments on three benchmark datasets demonstrate that the proposed method achieves state-of-the-art performance and greatly outperforms other scene text detection and segmentation approaches.

  12. 2016 PREP attitudes in Germany: high awareness and acceptance in MSM at risk of HIV.

    Science.gov (United States)

    Spinner, Christoph D; Hanhoff, Nikola; Krznaric, Ivanka; Knecht, Gaby; Kuemmerle, Tim; Ruesenberg, Robin; Schewe, Knud

    2018-02-24

    To examine current risk behavior, awareness, experience, and attitudes towards pre-exposure-prophylaxis (PrEP), and to estimate a potential impact on the prevention of HIV transmission among HIV-negative MSM in Germany. PrEP was not officially licensed at the time of survey. Web-based questionnaire from 03-06/2016. Potential participants were informed through social media, flyers, and advertisements. Risk contacts were defined as unprotected sexual intercourse under the influence of recreational drugs in the past 6 months. In total, 1208 subjects participated, 342 subjects were excluded for being HIV-infected or non-MSM, leaving 866 subjects to be evaluated in this analysis. Mean age was 37.0 ± 10.4 years. 593 participants (68.5%) were tested for HIV within the past 12 months. A total of 206 STDs in the past 6 months were reported by 144 (16.6%). Aware of PrEP was 748 (86.4%) respondents, while 65.1% reported willingness to use it. Risk behavior was significantly associated with higher PrEP acceptance (OR 2.90, 95% CI 2.14-3.90), as was a history of STDs (OR 1.85, 95% CI 1.17-2.91). The use of condoms would forgo 52.3% of subjects if taking PrEP. Sixty-five respondents (7.5%) reported PrEP use. Only 19 (29.2%) had accessed PrEP under medical supervision. PrEP use was reported by 14.8% with > 5 risk contacts in the past 6 months, compared to 6.3% with one risk contact (p awareness and acceptance, especially among subgroups of MSM at highest risk of HIV infection. Structured access and availability of PrEP to this population may have an important impact on the HIV epidemic in Germany.

  13. Reducing shame in a game that predicts HIV risk reduction for young adult MSM: a randomized trial delivered nationally over the web

    Directory of Open Access Journals (Sweden)

    John L Christensen

    2013-11-01

    Full Text Available Introduction: Men who have sex with men (MSM often face socially sanctioned disapproval of sexual deviance from the heterosexual “normal.” Such sexual stigma can be internalized producing a painful affective state (i.e., shame. Although shame (e.g., addiction can predict risk-taking (e.g., alcohol abuse, sexual shame's link to sexual risk-taking is unclear. Socially Optimized Learning in Virtual Environments (SOLVE was designed to reduce MSM's sexual shame, but whether it does so, and if that reduction predicts HIV risk reduction, is unclear. Objectives: To test if at baseline, MSM's reported past unprotected anal intercourse (UAI is related to shame; MSM's exposure to SOLVE compared to a wait-list control (WLC condition reduces MSM's shame; and shame-reduction mediates the link between WLC condition and UAI risk reduction. Methods: HIV-negative, self-identified African American, Latino or White MSM, aged 18–24 years, who had had UAI with a non-primary/casual partner in the past three months were recruited for a national online study. Eligible MSM were computer randomized to either WLC or a web-delivered SOLVE. Retained MSM completed baseline measures (e.g., UAI in the past three months; current level of shame and, in the SOLVE group, viewed at least one level of the game. At the end of the first session, shame was measured again. MSM completed follow-up UAI measures three months later. All data from 921 retained MSM (WLC condition, 484; SOLVE condition, 437 were analyzed, with missing data multiply imputed. Results: At baseline, MSM reporting more risky sexual behaviour reported more shame (r s=0.21; p<0.001. MSM in the SOLVE intervention reported more shame reduction (M=−0.08 than MSM in the control condition (M=0.07; t(919=4.24; p<0.001. As predicted, the indirect effect was significant (point estimate −0.10, 95% bias-corrected CI [−0.01 to −0.23] such that participants in the SOLVE treatment condition reported greater

  14. Reducing shame in a game that predicts HIV risk reduction for young adult MSM: a randomized trial delivered nationally over the Web.

    Science.gov (United States)

    Christensen, John L; Miller, Lynn Carol; Appleby, Paul Robert; Corsbie-Massay, Charisse; Godoy, Carlos Gustavo; Marsella, Stacy C; Read, Stephen J

    2013-11-13

    Men who have sex with men (MSM) often face socially sanctioned disapproval of sexual deviance from the heterosexual "normal." Such sexual stigma can be internalized producing a painful affective state (i.e., shame). Although shame (e.g., addiction) can predict risk-taking (e.g., alcohol abuse), sexual shame's link to sexual risk-taking is unclear. Socially Optimized Learning in Virtual Environments (SOLVE) was designed to reduce MSM's sexual shame, but whether it does so, and if that reduction predicts HIV risk reduction, is unclear. To test if at baseline, MSM's reported past unprotected anal intercourse (UAI) is related to shame; MSM's exposure to SOLVE compared to a wait-list control (WLC) condition reduces MSM's shame; and shame-reduction mediates the link between WLC condition and UAI risk reduction. HIV-negative, self-identified African American, Latino or White MSM, aged 18-24 years, who had had UAI with a non-primary/casual partner in the past three months were recruited for a national online study. Eligible MSM were computer randomized to either WLC or a web-delivered SOLVE. Retained MSM completed baseline measures (e.g., UAI in the past three months; current level of shame) and, in the SOLVE group, viewed at least one level of the game. At the end of the first session, shame was measured again. MSM completed follow-up UAI measures three months later. All data from 921 retained MSM (WLC condition, 484; SOLVE condition, 437) were analyzed, with missing data multiply imputed. At baseline, MSM reporting more risky sexual behaviour reported more shame (r s=0.21; p<0.001). MSM in the SOLVE intervention reported more shame reduction (M=-0.08) than MSM in the control condition (M=0.07; t(919)=4.24; p<0.001). As predicted, the indirect effect was significant (point estimate -0.10, 95% bias-corrected CI [-0.01 to -0.23] such that participants in the SOLVE treatment condition reported greater reductions in shame, which in turn predicted reductions in risky sexual

  15. An outlook on the scenes of paradigmatic changes in Astronomy

    Science.gov (United States)

    Girola, R.

    2009-05-01

    In this introduction I will put forward solutions which have been given to resolve the disagreements about the different models in the history of Astronomy from a didactic point of view. It is also about having a critical and prudent look concerning the risk of combining theories which may turn out apparently valid as it is in the case of the Tycho Brahe historical model. I will particularly focus on four models from a historical and epistemological perspective with the purpose of showing how the conflictive scene moved on to an efficient way out of the problem. To do so I will describe the variables in age, time and space(cognitive space and time of Astronomy) by confronting historical models with contemporary ones about the dispute concerning the Universe dynamic description. The Mond theory explains the difficulties in the interpretation of the rotation of the spiral galaxies claiming that Newton laws are not accurate in great scale, thus denying the solution of the missing matter. At the same time the rival theory refuses the solution given by its opponent Mond theory, through observations of galactic clusters in interaction, stating the existence of Dark Matter. The chosen historical confrontations are the following: (a) Heliocentric and Geocentric Model, (b) The origin of the 1920 debate: Curtis and Shapley, (c) The Red Shift of the Galaxies and the Unchanging Cosmology, and (d) Dark Matter and Newton's Laws as viewed from Mond Theory, which is about the present disagreement. The target focuses on showing the building up of both theories and the risk of combining them as well.

  16. HIV risk among MSM in Senegal: a qualitative rapid assessment of the impact of enforcing laws that criminalize same sex practices.

    Directory of Open Access Journals (Sweden)

    Tonia Poteat

    Full Text Available Men who have sex with men (MSM are at high risk for HIV in Senegal, with a prevalence of 21.5%. In December 2008, nine male HIV prevention workers were imprisoned for "acts against nature" prohibited by Senegalese law. This qualitative study assessed the impact of these arrests on HIV prevention efforts. A purposive sample of MSM in six regions of Senegal was recruited by network referral. 26 in-depth interviews (IDIs and 6 focus group discussions (FGDs were conducted in July-August 2009. 14 key informants were also interviewed. All participants reported pervasive fear and hiding among MSM as a result of the December 2008 arrests and publicity. Service providers suspended HIV prevention work with MSM out of fear for their own safety. Those who continued to provide services noticed a sharp decline in MSM participation. An effective response to the HIV epidemic in Senegal should include active work to decrease enforcement of this law.

  17. Use of geosocial networking (GSN) mobile phone applications to find men for sex by men who have sex with men (MSM) in Washington, DC.

    Science.gov (United States)

    Phillips, Gregory; Magnus, Manya; Kuo, Irene; Rawls, Anthony; Peterson, James; Jia, Yujiang; Opoku, Jenevieve; Greenberg, Alan E

    2014-09-01

    Current advances have added geosocial networking (GSN) mobile phone applications as an option for men who have sex with men (MSM) to meet other men. This is the first study to assess GSN application use and sex-seeking behaviors of MSM recruited using venue-based sampling. Among the 379 MSM in this study, 63.6 % reported using GSN applications to find men in the past year. Nearly one-quarter of MSM had sex with a man met using a GSN application in the prior year; these men were more likely to be under 35 years old and have had sex with a man met on the Internet; they were also less likely to be HIV-positive and have applications are a viable option for use in sampling and delivering interventions to young MSM who are often missed through other methods.

  18. Raise two effects with one scene: scene contexts have two separate effects in visual working memory of target faces

    OpenAIRE

    Tanabe-Ishibashi, Azumi; Ikeda, Takashi; Osaka, Naoyuki

    2014-01-01

    Many people have experienced the inability to recognize a familiar face in a changed context, a phenomenon known as the “butcher-on-the-bus” effect. Whether this context effect is a facilitation of memory by old contexts or a disturbance of memory by novel contexts is of great debate. Here, we investigated how two types of contextual information associated with target faces influence the recognition performance of the faces using meaningful (scene) or meaningless (scrambled scene) backgrounds...

  19. Raise two effects with one scene: Scene contexts have two separate effects in visual working memory of target faces.

    OpenAIRE

    Azumi eTanabe-Ishibashi; Takashi eIkeda; Naoyuki eOsaka

    2014-01-01

    Many people have experienced the inability to recognize a familiar face in a changed context, a phenomenon known as the butcher-on-the-bus effect. Whether this context effect is a facilitation of memory by old contexts or a disturbance of memory by novel contexts is of great debate. Here, we investigated how two types of contextual information associated with target faces influence the recognition performance of the faces using meaningful (scene) or meaningless (scrambled scene) backgrounds. ...

  20. Raise two effects with one scene: scene contexts have two separate effects in visual working memory of target faces.

    Science.gov (United States)

    Tanabe-Ishibashi, Azumi; Ikeda, Takashi; Osaka, Naoyuki

    2014-01-01

    Many people have experienced the inability to recognize a familiar face in a changed context, a phenomenon known as the "butcher-on-the-bus" effect. Whether this context effect is a facilitation of memory by old contexts or a disturbance of memory by novel contexts is of great debate. Here, we investigated how two types of contextual information associated with target faces influence the recognition performance of the faces using meaningful (scene) or meaningless (scrambled scene) backgrounds. The results showed two different effects of contexts: (1) disturbance on face recognition by changes of scene backgrounds and (2) weak facilitation of face recognition by the re-presentation of the same backgrounds, be it scene or scrambled. The results indicate that the facilitation and disturbance of context effects are actually caused by two different subcomponents of the background information: semantic information available from scene backgrounds and visual array information commonly included in a scene and its scrambled picture. This view suggests visual working memory system can control such context information, so that it switches the way to deal with the contexts information; inhibiting it as a distracter or activating it as a cue for recognizing the current target.

  1. Raise two effects with one scene: Scene contexts have two separate effects in visual working memory of target faces.

    Directory of Open Access Journals (Sweden)

    Azumi eTanabe-Ishibashi

    2014-05-01

    Full Text Available Many people have experienced the inability to recognize a familiar face in a changed context, a phenomenon known as the butcher-on-the-bus effect. Whether this context effect is a facilitation of memory by old contexts or a disturbance of memory by novel contexts is of great debate. Here, we investigated how two types of contextual information associated with target faces influence the recognition performance of the faces using meaningful (scene or meaningless (scrambled scene backgrounds. The results showed two different effects of contexts: (1 disturbance on face recognition by changes of scene backgrounds and (2 weak facilitation of face recognition by the re-presentation of the same backgrounds, be it scene or scrambled. The results indicate that the facilitation and disturbance of context effects are actually caused by different two subcomponents of the background information: semantic information available from scene backgrounds and visual-array information commonly included in a scene and its scrambled picture. This view suggests visual working memory system can control such context information, so that it switches the way to deal with the contexts information; inhibiting it as a distracter or activating it as a cue for recognizing the current target.

  2. Prospective cohort study of HIV incidence and molecular characteristics of HIV among men who have sex with men(MSM) in Yunnan Province, China.

    Science.gov (United States)

    Xu, Junjie; An, Minghui; Han, Xiaoxu; Jia, Manhong; Ma, Yanling; Zhang, Min; Hu, Qinghai; Chu, Zhenxing; Zhang, Jing; Jiang, Yongjun; Geng, Wenqing; Lu, Lin; Shang, Hong

    2013-01-04

    Yunnan has the largest number of reported HIV/AIDS cases among all Chinese provinces, the reported prevalence of HIV among Yunnan men who have sex with men (MSM) passed 10%, while HIV incidence epidemic and molecular characteristics of new infected Yunnan MSM were not evaluated before. An 18 months prospective followed up with a frequency of 3 month per visit were conducted among HIV seronegative MSM in Kunming cityduring 2009-2011. Interviewer-administrated questionnaires were carried out. Blood specimens were obtained to test for syphilis and HIV, in which HIV were evaluated by standard HIV enzyme immunoassay (EIA) and HIV nucleic acid amplification testing (NAAT). Near full-length regions of the HIV-1 were evaluated for subtyping, primary drug resistance mutations. During the follow-up 70.1% of the recruited 378 MSM retained in the cohort. Eleven MSM seroconverted to HIV and fifteen MSM seroconverted to syphilis. The HIV incidence and syphilis incidence was 3.5 (95% CI 1.8-6.2) cases /100 person year(PY) and 5.3 (95% CI 3.0-8.7) cases/100 PY, respectively. Multivariate analysis showed that baseline syphilis infection (aHR, 17.7), occupation (students vs. others [aHR, 5.7], retirees vs. others [aHR, 4.1]), bleeding experience after receptive anal intercourse (aHR,7.6), and minority ethnic(vs. Han) [aHR, 5.7] were independent risk factors for HIV seroconversion(each PHIV transmission pairs were detected among seroconverted minority ethnic MSM. HIV incidence was moderately high among Yunnan MSM. Yunnan province need to strengthen both HIV and syphilis screening among MSM population. Some subpopulations of MSM, such as students, retirees and minority ethnic groups require more HIV epidemic surveillance and strengthened behavior interventions. HIV subtypes and primary drug resistance should be continually monitored to track cross-group transmission of HIV strains.

  3. New emerging recombinant HIV-1 strains and close transmission linkage of HIV-1 strains in the Chinese MSM population indicate a new epidemic risk.

    Directory of Open Access Journals (Sweden)

    Jianjun Wu

    Full Text Available In recent years, the population of men who have sex with men (MSM have become the most significant increasing group of HIV-1 transmission in China. To identify new recombinant strains and transmission patterns of HIV-1 in Chinese MSM population, a cross-sectional investigation of MSM in Anhui Province (in south-eastern China was performed in 2011. The diagnosed AIDS case rate, CD4 T-cell counts, HIV subtypes, and origin of the recombinant strains were investigated in 138 collected samples. The phylogenetic and bootscan analyses demonstrated that, apart from three previously reported circulating strains (CRF07_BC, CRF01_AE, subtype B, various recombinant strains among subtype B, subtype C, CRF01_AE, and CRF07_BC were simultaneously identified in Chinese MSM for the first time. The introducing time of B subtype in Chinese MSM populations was estimated in 1985, CRF01_AE in 2000, and CRF07_BC in 2003; the latter two account for more than 85% of MSM infections. Notably, in comparison with B subtype infections in Anhui MSM, CRF01_AE, with the highest prevalence rate, may accelerate AIDS progression. Over half of patients (56% infected with new recombinant strains infection are diagnosed as progression into AIDS. Both Bayes and phylogenetic analyses indicated that there was active HIV transmission among MSM nationwide, which may facilitate the transmission of the new 01B recombinant strains in MSM. In conclusion, new recombinant strains and active transmission were identified in the Chinese MSM population, which may lead to a new alarming HIV pandemic in this population due to the increased pathogenesis of the newly emerging strains.

  4. Association Between Enacted Stigma and HIV-Related Risk Behavior Among MSM, National HIV Behavioral Surveillance System, 2011.

    Science.gov (United States)

    Balaji, Alexandra B; Bowles, Kristina E; Hess, Kristen L; Smith, Justin C; Paz-Bailey, Gabriela

    2017-01-01

    MSM bear a disproportionate burden of the HIV epidemic. Enacted stigma (overt negative actions) against sexual minorities may play an important role in increasing HIV risk among this population. Using data from the 2011 National HIV Behavioral Surveillance system, MSM cycle, we examined the independent associations between three measures of enacted stigma (verbal harassment, discrimination, physical assault) and engagement in each of four HIV-related risk behaviors as outcomes: condomless anal intercourse (CAI) at last sex with a male partner of HIV discordant or unknown status and, in the past 12 months, CAI with a male partner, ≥4 male sex partners, and exchange sex. Of 9819 MSM, 32% experienced verbal harassment in the past 12 months, 23% experienced discrimination, and 8% experienced physical assault. Discordant CAI at last sex with a male partner was associated with previous discrimination and physical assault. Past 12 month CAI with a male partner, ≥4 male sex partners, and exchange sex were each associated with verbal harassment, discrimination, and physical assault. These findings indicate that a sizable proportion of MSM report occurrences of past 12 month enacted stigma and suggest that these experiences may be associated with HIV-related risk behavior. Addressing stigma towards sexual minorities must involve an integrated, multi-faceted approach, including interventions at the individual, community, and societal level.

  5. Does online dating lead to higher sexual risk behaviour? A cross-sectional study among MSM in Amsterdam, the Netherlands

    NARCIS (Netherlands)

    Heijman, Titia; Stolte, Ineke; Geskus, Ronald; Matser, Amy; Davidovich, Udi; Xiridou, Maria; Schim van der Loeff, Maarten

    2016-01-01

    Men having sex with men (MSM) frequently use the Internet to find sex partners. We examined the association between unprotected anal intercourse (UAI) with partners dated online and with partners dated offline (met elsewhere), and examined whether differences can be explained by self-perceived HIV

  6. Behavioral interventions to reduce HIV risk behavior for MSM and transwomen in Southeast Asia: a systematic review.

    Science.gov (United States)

    Nugroho, Adi; Erasmus, Vicki; Zomer, Tizza P; Wu, Qing; Richardus, Jan Hendrik

    2017-01-01

    This systematic review aims to gain insights from existing literature from Southeast Asian countries to improve future HIV prevention programs for men who have sex with men (MSM) and transgender women (transwomen). We conducted a systematic search in six international databases for literature published prior to 1 January 2015. We included studies describing behavioral interventions targeting MSM and/or transwomen, and conducted in at least one Southeast Asian country. Five out of 575 screened studies met the inclusion criteria and reported a significant intervention effect on at least one outcome measure, that is, condom use (with casual or commercial partner), water-based lubricant use, number of sex partners, HIV prevention knowledge, or willingness to use pre-exposure prophylaxis. Peer education/outreach was the most commonly employed type of intervention in the five included studies and was usually delivered as an element of a larger intervention package, together with condom distribution and the provision of drop-in centers. Motivational interviewing was effective, while internet-based interventions appeared to be a viable platform for intervention delivery. Nevertheless, research on behavioral interventions among MSM and transwomen in Southeast Asia is limited. Future interventions should be culturally appropriate, theoretically grounded, and rigorously evaluated. Only then can we best address the HIV epidemic among MSM and transwomen in this region.

  7. Relation between HIV status, risky sexual behavior, and mental health in an MSM sample from three Chilean cities.

    Science.gov (United States)

    Gómez, Fabiola; Barrientos, Jaime; Cárdenas, Manuel

    2017-04-20

    To explore the association among HIV status; negative psychological symptoms (anxiety, depression, and hostility); and risky sexual behaviors (multiple sexual partners and unprotected sexual intercourse) in a Chilean sample of men who have sex with men (MSM). This study had a cross-sectional design and a sample of 325 MSM whose ages ranged from 18 to 64 years (mean: 30.8; standard deviation: 9.8). Association tests (chi-squared) and group mean comparisons (Student's t-tests and F-tests) were performed. No statistically significant differences were found for condom use or for the number of sexual partners between HIV-positive men and those who are not infected. In both groups, about 50% reported sexual encounters without condom use in the past six months. There were statistically significant differences in symptoms associated with depression between the two groups. These results reveal the need to strengthen messages about the importance of condom use, as the only way to prevent HIV, and as a means of preventing HIV infection and reinfection, in national prevention and self-care programs for sexually active subjects. More studies are needed in Latin America to advance HIV prevention efforts for the MSM population. The data generated by this study can be used to inform the development of HIV prevention programming strategies and interventions targeting the MSM population in Latin America.

  8. Risk factors for anal high-grade squamous intraepithelial lesions in HIV-positive MSM: is targeted screening possible?

    NARCIS (Netherlands)

    Siegenbeek van Heukelom, Matthijs L.; Marra, Elske; de Vries, Henry J. C.; Schim van der Loeff, Maarten F.; Prins, Jan M.

    2017-01-01

    HIV-positive MSM are at increased risk for developing anal squamous cell carcinoma. Detection of precursor lesions of anal cancer [anal high-grade squamous intraepithelial lesions (HSIL)] is cumbersome and expensive. Our objective was to identify potential risk factors for anal HSIL in HIV-positive

  9. RONI-based steganographic method for 3D scene

    Science.gov (United States)

    Li, Xiao-Wei; Wang, Qiong-Hua

    2017-06-01

    Image steganography is one way of data hiding which provides data security in digital images. The aim is to embed and deliver secret data in digital images without any suspiciousness. However, most of the existing optical image hiding methods ignore the visual quality of the stego-image for improving the robustness of the secret image. To address this issue, in this paper, we present a Region of Non-Interest (RONI) steganographic algorithm to enhance the visual quality of the stego-image. In the proposed method, the carrier image is segmented into Region of Interest (ROI) and RONI. To enhance the visual quality, the 3D image information is embedded into the RONI of the digital images. In order to find appropriate regions for embedding, we use a visual attention model as a means of measuring the ROI of the digital images. The algorithm employs the computational integral imaging (CII) technique to hide the 3D scene in the carrier image. Comparison results show that the proposed technique performs better than some existing state of art techniques.

  10. Sound Classification in Hearing Aids Inspired by Auditory Scene Analysis

    Directory of Open Access Journals (Sweden)

    Norbert Dillier

    2005-11-01

    Full Text Available A sound classification system for the automatic recognition of the acoustic environment in a hearing aid is discussed. The system distinguishes the four sound classes “clean speech,” “speech in noise,” “noise,” and “music.” A number of features that are inspired by auditory scene analysis are extracted from the sound signal. These features describe amplitude modulations, spectral profile, harmonicity, amplitude onsets, and rhythm. They are evaluated together with different pattern classifiers. Simple classifiers, such as rule-based and minimum-distance classifiers, are compared with more complex approaches, such as Bayes classifier, neural network, and hidden Markov model. Sounds from a large database are employed for both training and testing of the system. The achieved recognition rates are very high except for the class “speech in noise.” Problems arise in the classification of compressed pop music, strongly reverberated speech, and tonal or fluctuating noises.

  11. Object segmentation controls image reconstruction from natural scenes.

    Science.gov (United States)

    Neri, Peter

    2017-08-01

    The structure of the physical world projects images onto our eyes. However, those images are often poorly representative of environmental structure: well-defined boundaries within the eye may correspond to irrelevant features of the physical world, while critical features of the physical world may be nearly invisible at the retinal projection. The challenge for the visual cortex is to sort these two types of features according to their utility in ultimately reconstructing percepts and interpreting the constituents of the scene. We describe a novel paradigm that enabled us to selectively evaluate the relative role played by these two feature classes in signal reconstruction from corrupted images. Our measurements demonstrate that this process is quickly dominated by the inferred structure of the environment, and only minimally controlled by variations of raw image content. The inferential mechanism is spatially global and its impact on early visual cortex is fast. Furthermore, it retunes local visual processing for more efficient feature extraction without altering the intrinsic transduction noise. The basic properties of this process can be partially captured by a combination of small-scale circuit models and large-scale network architectures. Taken together, our results challenge compartmentalized notions of bottom-up/top-down perception and suggest instead that these two modes are best viewed as an integrated perceptual mechanism.

  12. Emerging technologies for HIV prevention for MSM: what we have learned, and ways forward.

    Science.gov (United States)

    Sullivan, Patrick S; Grey, Jeremy A; Simon Rosser, Brian R

    2013-06-01

    Technology-enabled HIV research and prevention has emerged in the past 10 years as an exciting dynamic field that offers great potential to help bring HIV prevention efforts to scale in key risk communities. Evolutions in technologies and in HIV epidemics suggest mutual opportunities to reach most at risk populations in novel ways. New technologies cannot completely replace interventions and services currently delivered by the people. However, we suggest that emerging technologies hold promise to bring services to scale and produce efficiencies in reaching rural populations of men who have sex with men (MSM), connecting with populations who are not reached in current urban outreach efforts, and providing services or research surveys that can be described algorithmically. Furthermore, the types of technologies (eg, internet-based, smartphone-based, text messaging) should be matched with both the content to be delivered and the technology usage patterns of target populations. We suggest several key principles and lessons learned that comprise a framework in which to consider the opportunities of technologies and HIV prevention and research. Future directions include improvement of data quality in online surveying, better characterization of biases, developing improved sampling approaches, working with funders to ensure compatibility of funding mechanisms and online research proposals, and promoting consensus approaches to the duplication and presentation of research and program evaluation results from online research. Given the current calls for comprehensive packages of prevention services for MSM, effective prevention might require an intentional combination of technology-enabled prevention services to achieve scale and strategic use of personally delivered package components in cases where non-algorithmic services, such as individualized counseling, are needed.

  13. Are fixations in static natural scenes a useful predictor of attention in the real world?

    Science.gov (United States)

    Foulsham, Tom; Kingstone, Alan

    2017-06-01

    Research investigating scene perception normally involves laboratory experiments using static images. Much has been learned about how observers look at pictures of the real world and the attentional mechanisms underlying this behaviour. However, the use of static, isolated pictures as a proxy for studying everyday attention in real environments has led to the criticism that such experiments are artificial. We report a new study that tests the extent to which the real world can be reduced to simpler laboratory stimuli. We recorded the gaze of participants walking on a university campus with a mobile eye tracker, and then showed static frames from this walk to new participants, in either a random or sequential order. The aim was to compare the gaze of participants walking in the real environment with fixations on pictures of the same scene. The data show that picture order affects interobserver fixation consistency and changes looking patterns. Critically, while fixations on the static images overlapped significantly with the actual real-world eye movements, they did so no more than a model that assumed a general bias to the centre. Remarkably, a model that simply takes into account where the eyes are normally positioned in the head-independent of what is actually in the scene-does far better than any other model. These data reveal that viewing patterns to static scenes are a relatively poor proxy for predicting real world eye movement behaviour, while raising intriguing possibilities for how to best measure attention in everyday life. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  14. Characteristics of late presentation of HIV infection in MSM and heterosexual adults in Portugal 2011–2013

    Directory of Open Access Journals (Sweden)

    Tara Shivaji

    2014-11-01

    Full Text Available Introduction: It is estimated that over half of newly diagnosed HIV infections in Europe present late. An HIV positive individual presenting late to care represents a missed opportunity to benefit from treatment, increasing the risk of morbidity and mortality at an individual level, and onward disease transmission at population level. Reducing late presentation is a strategic priority of the Portuguese HIV/AIDS program. We set out to describe the characteristics of late presentation in the two largest transmission risk groups currently in Portugal to inform HIV prevention and treatment. Methods: We extracted details of all notified cases from individuals over 15 years with a laboratory confirmed HIV diagnosis made between January 2011 and December 2013 from the Portuguese HIV surveillance database and selected cases from heterosexuals and men who have sex with men (MSM. We defined late presentation as an initial CD4 count <350 cells/mm3 or presence of AIDS-defining disease at time of HIV diagnosis. We calculated adjusted odds ratios (aOR with 95% confidence intervals (CI for characteristics associated with late presentation in separate logistic regression for heterosexuals and MSM. Results: Of 4219 HIV positive cases notified, 2589 (61% were heterosexuals and 1220 (29% were MSM. A total of 1586 (38% cases presented late of which 1037 (40% were heterosexual and 328 (27% were MSM. The median age at late presentation was 40 in heterosexual women, 46 in heterosexual men and 35 in MSM. A total of 1446 (55% of heterosexual HIV positive adults were unaware of having had a high risk sexual contact. Late presentation among heterosexuals was associated with being male (aOR=1.58 95% CI 1.29–1.93, not knowing a partners’ HIV status (OR=1.59 95% CI 1.35–1.87 and age, increasing the odds of late presentation by a factor of 1.02 per year (95% CI 1.01–1.03. Among MSM, only age was associated with late presentation, increasing by 1.04 (95% CI 1.03–1

  15. Utilising E-on Vue and Unity 3D scenes to generate synthetic images and videos for visible signature analysis

    Science.gov (United States)

    Madden, Christopher S.; Richards, Noel J.; Culpepper, Joanne B.

    2016-10-01

    This paper investigates the ability to develop synthetic scenes in an image generation tool, E-on Vue, and a gaming engine, Unity 3D, which can be used to generate synthetic imagery of target objects across a variety of conditions in land environments. Developments within these tools and gaming engines have allowed the computer gaming industry to dramatically enhance the realism of the games they develop; however they utilise short cuts to ensure that the games run smoothly in real-time to create an immersive effect. Whilst these short cuts may have an impact upon the realism of the synthetic imagery, they do promise a much more time efficient method of developing imagery of different environmental conditions and to investigate the dynamic aspect of military operations that is currently not evaluated in signature analysis. The results presented investigate how some of the common image metrics used in target acquisition modelling, namely the Δμ1, Δμ2, Δμ3, RSS, and Doyle metrics, perform on the synthetic scenes generated by E-on Vue and Unity 3D compared to real imagery of similar scenes. An exploration of the time required to develop the various aspects of the scene to enhance its realism are included, along with an overview of the difficulties associated with trying to recreate specific locations as a virtual scene. This work is an important start towards utilising virtual worlds for visible signature evaluation, and evaluating how equivalent synthetic imagery is to real photographs.

  16. Measuring stigma affecting sex workers (SW) and men who have sex with men (MSM): A systematic review.

    Science.gov (United States)

    Fitzgerald-Husek, Alanna; Van Wert, Michael J; Ewing, Whitney F; Grosso, Ashley L; Holland, Claire E; Katterl, Rachel; Rosman, Lori; Agarwal, Arnav; Baral, Stefan D

    2017-01-01

    Stigma involves discrediting a person or group based on a perceived attribute, behaviour or reputation associated with them. Sex workers (SW) and men who have sex with men (MSM) are key populations who are often at increased risk for the acquisition and transmission of HIV and who are affected by stigma that can negatively impact their health and well-being. Although stigma was included as an indicator in the US National HIV/AIDS Strategic Plan and there have been consultations focused on adding a stigma indicator within PEPFAR and the Global Fund in relation to potentiating HIV risks among key populations, there remains limited consensus on the appropriate measurement of SW- or MSM-associated stigma. Consequently, this systematic review summarizes studies using quantitative, qualitative, or mixed methods approaches to measure stigma affecting sex workers and men who have sex with men. This systematic review included English, French, and Spanish peer-reviewed research of any study design measuring SW- or MSM-associated stigma. Articles were published from January 1, 2004 to March 26, 2014 in PsycINFO, PubMed, EMBASE, CINAHL Plus, Global Health, and World Health Organization Global Health Library Regional Indexes. Of the 541 articles reviewed, the majority measured stigma toward MSM (over 97%), were conducted in North America, used quantitative methods, and focused on internalized stigma. With the inclusion of addressing stigma in several domestic and international HIV strategies, there is a need to ensure the use of validated metrics for stigma. The field to date has completed limited measurement of stigma affecting sex workers, and limited measurement of stigma affecting MSM outside of higher income settings. Moving forward requires a concerted effort integrating validated metrics of stigma into health-related surveys and programs for key populations.

  17. Engagement in group sex among geosocial networking (GSN) mobile application-using men who have sex with men (MSM)

    Science.gov (United States)

    Phillips, Gregory; Grov, Christian; Mustanski, Brian

    2015-01-01

    Background Men who have sex with men (MSM) remain the group most affected by the HIV epidemic in the United States. At least one-quarter of MSM report engagement in group sex events (GSEs), which can pose a risk for HIV transmission and acquisition. In this study, we sought to identify event-level correlates of sexual and drug use behaviors at GSEs to better inform prevention activities. Methods For this study, we recruited participants via banner and pop-up advertisements placed on a geosocial networking mobile phone application for MSM to meet. Results Of the 1,997 individuals who completed the study screener, 36.0% reported participating in at least one GSE in the prior year. In multivariable logistic regression, attendance at a GSE in the past year was significantly associated with older age, full/part time employment, and being HIV-positive. Of the men who attended a GSE, more than half reported condomless anal sex (CAS) with at least one of their partners (insertive: 57.7%; receptive: 56.3%). MSM who indicated drug use had significantly higher odds of having insertive CAS (odds ratio (OR) = 2.45; 95% confidence interval (CI): 1.37, 4.39) and receptive CAS (OR = 3.60; 95% CI: 1.96, 6.63) at their last GSE. Conclusions The high prevalence of HIV-positive MSM engaging in group sex, coupled with their greater odds of CAS, poses a significant risk for HIV/STI transmission within the group sex setting. More research is needed to determine patterns of condom use at these events, and whether seroadaptive behaviors are driving CAS. PMID:26255156

  18. Does online dating lead to higher sexual risk behaviour? A cross-sectional study among MSM in Amsterdam, the Netherlands.

    Science.gov (United States)

    Heijman, Titia; Stolte, Ineke; Geskus, Ronald; Matser, Amy; Davidovich, Udi; Xiridou, Maria; Schim van der Loeff, Maarten

    2016-06-14

    Men having sex with men (MSM) frequently use the Internet to find sex partners. We examined the association between unprotected anal intercourse (UAI) with partners dated online and with partners dated offline (met elsewhere), and examined whether differences can be explained by self-perceived HIV status of the index and knowledge of partnership characteristics. MSM were recruited at the Sexually Transmitted Infections Clinic in Amsterdam, in 2008-2009. Participants completed a questionnaire concerning sexual behaviour. Only men reporting both online and offline casual sex partners were included. We assessed the association between online/offline partner dating and UAI, using random-effects logistic regression analysis. Five hundred seventy-seven men (351 HIV-negative, 153 HIV-positive, and 73 HIV-unaware) reported UAI in 26 % of 878 online, and 23 % of 903 offline casual partnerships. The crude OR of online dating for UAI was 1.36 (95 % CI 1.03-1.81). HIV-positive men were more likely to report UAI than HIV-negative men (49 % vs. 28 % of partnerships). Adjusted for demographic characteristics, online dating had no significant effect on UAI among HIV-negative and HIV status-unaware men, but HIV-positive men were more likely to have UAI with online partners (aOR = 1.65 [95 % CI 1.05-2.57]). After correction for partner and partnership characteristics the effect of online/offline dating on UAI among HIV-positive MSM was reduced and no longer significant. Online dating was not significantly associated with UAI among HIV-negative MSM. HIV-positive MSM were more likely to practise UAI with partners dated online; however, after correction for partner and partnership characteristics, online partnership acquisition was not associated with a significantly increased risk of UAI.

  19. Measuring stigma affecting sex workers (SW and men who have sex with men (MSM: A systematic review.

    Directory of Open Access Journals (Sweden)

    Alanna Fitzgerald-Husek

    Full Text Available Stigma involves discrediting a person or group based on a perceived attribute, behaviour or reputation associated with them. Sex workers (SW and men who have sex with men (MSM are key populations who are often at increased risk for the acquisition and transmission of HIV and who are affected by stigma that can negatively impact their health and well-being. Although stigma was included as an indicator in the US National HIV/AIDS Strategic Plan and there have been consultations focused on adding a stigma indicator within PEPFAR and the Global Fund in relation to potentiating HIV risks among key populations, there remains limited consensus on the appropriate measurement of SW- or MSM-associated stigma. Consequently, this systematic review summarizes studies using quantitative, qualitative, or mixed methods approaches to measure stigma affecting sex workers and men who have sex with men.This systematic review included English, French, and Spanish peer-reviewed research of any study design measuring SW- or MSM-associated stigma. Articles were published from January 1, 2004 to March 26, 2014 in PsycINFO, PubMed, EMBASE, CINAHL Plus, Global Health, and World Health Organization Global Health Library Regional Indexes. Of the 541 articles reviewed, the majority measured stigma toward MSM (over 97%, were conducted in North America, used quantitative methods, and focused on internalized stigma.With the inclusion of addressing stigma in several domestic and international HIV strategies, there is a need to ensure the use of validated metrics for stigma. The field to date has completed limited measurement of stigma affecting sex workers, and limited measurement of stigma affecting MSM outside of higher income settings. Moving forward requires a concerted effort integrating validated metrics of stigma into health-related surveys and programs for key populations.

  20. Uncertainty in a Markov state model with missing states and rates: Application to a room temperature kinetic model obtained using high temperature molecular dynamics

    Science.gov (United States)

    Chatterjee, Abhijit; Bhattacharya, Swati

    2015-09-01

    Several studies in the past have generated Markov State Models (MSMs), i.e., kinetic models, of biomolecular systems by post-analyzing long standard molecular dynamics (MD) calculations at the temperature of interest and focusing on the maximally ergodic subset of states. Questions related to goodness of these models, namely, importance of the missing states and kinetic pathways, and the time for which the kinetic model is valid, are generally left unanswered. We show that similar questions arise when we generate a room-temperature MSM (denoted MSM-A) for solvated alanine dipeptide using state-constrained MD calculations at higher temperatures and Arrhenius relation — the main advantage of such a procedure being a speed-up of several thousand times over standard MD-based MSM building procedures. Bounds for rate constants calculated using probability theory from state-constrained MD at room temperature help validate MSM-A. However, bounds for pathways possibly missing in MSM-A show that alternate kinetic models exist that produce the same dynamical behaviour at short time scales as MSM-A but diverge later. Even in the worst case scenario, MSM-A is found to be valid longer than the time required to generate it. Concepts introduced here can be straightforwardly extended to other MSM building techniques.

  1. 3D Road Scene Monitoring Based on Real-Time Panorama

    Directory of Open Access Journals (Sweden)

    Yuezhou Wu

    2014-01-01

    Full Text Available Road monitoring helps to control the regional traffic situation so as to adjust the traffic flow. Real-time panorama is conducive to timely treat traffic accidents and to greatly improve traffic capacity. This paper designs a 3D road scene monitoring framework based on real-time panorama. The system is the combination of large scale panorama, satellite map textures, and 3D scene model, in which users can ramble freely. This paper has the following contributions. Firstly, land-points were extracted followed by motion detection, then comotion algorithm was applied to land-points from adjacent cameras, and homography matrix was constructed. Secondly, reference camera was chosen and transformed to overhead viewpoint; subsequently multiviews were morphed to the same viewpoint and stitched to panorama. Finally, the registration based on high-precision GPS information between 2D road panorama and 3D scene model was also proposed. The proposed framework has been successfully applied to a large road intersection monitoring. Experimental results are furnished at the end of the paper.

  2. Integration of virtual and real scenes within an integral 3D imaging environment

    Science.gov (United States)

    Ren, Jinsong; Aggoun, Amar; McCormick, Malcolm

    2002-11-01

    The Imaging Technologies group at De Montfort University has developed an integral 3D imaging system, which is seen as the most likely vehicle for 3D television avoiding psychological effects. To create real fascinating three-dimensional television programs, a virtual studio that performs the task of generating, editing and integrating the 3D contents involving virtual and real scenes is required. The paper presents, for the first time, the procedures, factors and methods of integrating computer-generated virtual scenes with real objects captured using the 3D integral imaging camera system. The method of computer generation of 3D integral images, where the lens array is modelled instead of the physical camera is described. In the model each micro-lens that captures different elemental images of the virtual scene is treated as an extended pinhole camera. An integration process named integrated rendering is illustrated. Detailed discussion and deep investigation are focused on depth extraction from captured integral 3D images. The depth calculation method from the disparity and the multiple baseline method that is used to improve the precision of depth estimation are also presented. The concept of colour SSD and its further improvement in the precision is proposed and verified.

  3. Special effects used in creating 3D animated scenes-part 1

    Science.gov (United States)

    Avramescu, A. M.

    2015-11-01

    In present, with the help of computer, we can create special effects that look so real that we almost don't perceive them as being different. These special effects are somehow hard to differentiate from the real elements like those on the screen. With the increasingly accesible 3D field that has more and more areas of application, the 3D technology goes easily from architecture to product designing. Real like 3D animations are used as means of learning, for multimedia presentations of big global corporations, for special effects and even for virtual actors in movies. Technology, as part of the movie art, is considered a prerequisite but the cinematography is the first art that had to wait for the correct intersection of technological development, innovation and human vision in order to attain full achievement. Increasingly more often, the majority of industries is using 3D sequences (three dimensional). 3D represented graphics, commercials and special effects from movies are all designed in 3D. The key for attaining real visual effects is to successfully combine various distinct elements: characters, objects, images and video scenes; like all these elements represent a whole that works in perfect harmony. This article aims to exhibit a game design from these days. Considering the advanced technology and futuristic vision of designers, nowadays we have different and multifarious game models. Special effects are decisively contributing in the creation of a realistic three-dimensional scene. These effects are essential for transmitting the emotional state of the scene. Creating the special effects is a work of finesse in order to achieve high quality scenes. Special effects can be used to get the attention of the onlooker on an object from a scene. Out of the conducted study, the best-selling game of the year 2010 was Call of Duty: Modern Warfare 2. This way, the article aims for the presented scene to be similar with many locations from this type of games, more

  4. 3D Aware Correction and Completion of Depth Maps in Piecewise Planar Scenes

    KAUST Repository

    Thabet, Ali Kassem

    2015-04-16

    RGB-D sensors are popular in the computer vision community, especially for problems of scene understanding, semantic scene labeling, and segmentation. However, most of these methods depend on reliable input depth measurements, while discarding unreliable ones. This paper studies how reliable depth values can be used to correct the unreliable ones, and how to complete (or extend) the available depth data beyond the raw measurements of the sensor (i.e. infer depth at pixels with unknown depth values), given a prior model on the 3D scene. We consider piecewise planar environments in this paper, since many indoor scenes with man-made objects can be modeled as such. We propose a framework that uses the RGB-D sensor’s noise profile to adaptively and robustly fit plane segments (e.g. floor and ceiling) and iteratively complete the depth map, when possible. Depth completion is formulated as a discrete labeling problem (MRF) with hard constraints and solved efficiently using graph cuts. To regularize this problem, we exploit 3D and appearance cues that encourage pixels to take on depth values that will be compatible in 3D to the piecewise planar assumption. Extensive experiments, on a new large-scale and challenging dataset, show that our approach results in more accurate depth maps (with 20 % more depth values) than those recorded by the RGB-D sensor. Additional experiments on the NYUv2 dataset show that our method generates more 3D aware depth. These generated depth maps can also be used to improve the performance of a state-of-the-art RGB-D SLAM method.

  5. From (UnWillingness to InvolveMENt: Development of a Successful Study Brand for Recruitment of Diverse MSM to a Longitudinal HIV Research

    Directory of Open Access Journals (Sweden)

    Paula M. Frew

    2013-01-01

    Full Text Available Background. HIV continues to be a major concern among MSM, yet Black MSM have not been enrolled in HIV research studies in proportionate numbers to White MSM. We developed an HIV prevention research brand strategy for MSM. Methods. Questionnaires and focus groups were conducted with 54 participants. Descriptive statistics and chi-square analyses were performed and qualitative data were transcribed and content analyzed to identify common themes. Results. Formative research results indicated that younger Black MSM (18–29 years were less likely to think about joining prevention studies compared to older (≥30 years Black MSM (x2=5.92, P=0.015. Qualitative and quantitative results indicate four prominent themes related to brand development: (1 communication sources (message deliverer, (2 message (impact of public health messaging on perceptions of HIV research, (3 intended audience (underlying issues that influence personal relevance of HIV research, and (4 communication channels (reaching intended audiences. Conclusion. The findings highlight the importance of behavioral communication translational research to effectively engage hard-to-reach populations. Despite reservations, MSM in our formative study expressed a need for active involvement and greater education to facilitate their engagement in HIV prevention research. Thus, the brand concept of “InvolveMENt” emerged.

  6. From (Un)Willingness to InvolveMENt: Development of a Successful Study Brand for Recruitment of Diverse MSM to a Longitudinal HIV Research.

    Science.gov (United States)

    Frew, Paula M; Williams, Victoria A; Shapiro, Eve T; Sanchez, Travis; Rosenberg, Eli S; Fenimore, Vincent L; Sullivan, Patrick S

    2013-11-21

    HIV continues to be a major concern among MSM, yet Black MSM have not been enrolled in HIV research studies in proportionate numbers to White MSM. We developed an HIV prevention research brand strategy for MSM. Questionnaires and focus groups were conducted with 54 participants. Descriptive statistics and chi-square analyses were performed and qualitative data were transcribed and content analyzed to identify common themes. Formative research results indicated that younger Black MSM (18-29 years) were less likely to think about joining prevention studies compared to older (≥30 years) Black MSM (x2 = 5.92, P = 0.015). Qualitative and quantitative results indicate four prominent themes related to brand development: (1) communication sources (message deliverer), (2) message (impact of public health messaging on perceptions of HIV research), (3) intended audience (underlying issues that influence personal relevance of HIV research), and (4) communication channels (reaching intended audiences). The findings highlight the importance of behavioral communication translational research to effectively engage hard-to-reach populations. Despite reservations, MSM in our formative study expressed a need for active involvement and greater education to facilitate their engagement in HIV prevention research. Thus, the brand concept of "InvolveMENt" emerged.

  7. Surface color perception in three-dimensional scenes.

    Science.gov (United States)

    Boyaci, Huseyin; Doerschner, Katja; Snyder, Jacqueline L; Maloney, Laurence T

    2006-01-01

    Researchers studying surface color perception have typically used stimuli that consist of a small number of matte patches (real or simulated) embedded in a plane perpendicular to the line of sight (a "Mondrian," Land & McCann, 1971). Reliable estimation of the color of a matte surface is a difficult if not impossible computational problem in such limited scenes (Maloney, 1999). In more realistic, three-dimensional scenes the difficulty of the problem increases, in part, because the effective illumination incident on the surface (the light field) now depends on surface orientation and location. We review recent work in multiple laboratories that examines (1) the degree to which the human visual system discounts the light field in judging matte surface lightness and color and (2) what illuminant cues the visual system uses in estimating the flow of light in a scene.

  8. A Grouped Threshold Approach for Scene Identification in AVHRR Imagery

    Science.gov (United States)

    Baum, Bryan A.; Trepte, Qing

    1999-01-01

    The authors propose a grouped threshold method for scene identification in Advanced Very High Resolution Radiometer imagery that may contain clouds, fire, smoke, or snow. The philosophy of the approach is to build modules that contain groups of spectral threshold tests that are applied concurrently, not sequentially, to each pixel in an image. The purpose of each group of tests is to identify uniquely a specific class in the image, such as smoke. A strength of this approach is that insight into the limits used in the threshold tests may be gained through the use of radiative transfer theory. Methodology and examples are provided for two different scenes, one containing clouds, forest fires, and smoke; and the other containing clouds over snow in the central United States. For both scenes, a limited amount of supporting information is provided by surface observers.

  9. Color appearance and color rendering of HDR scenes: an experiment

    Science.gov (United States)

    Parraman, Carinna; Rizzi, Alessandro; McCann, John J.

    2009-01-01

    In order to gain a deeper understanding of the appearance of coloured objects in a three-dimensional scene, the research introduces a multidisciplinary experimental approach. The experiment employed two identical 3-D Mondrians, which were viewed and compared side by side. Each scene was subjected to different lighting conditions. First, we used an illumination cube to diffuse the light and illuminate all the objects from each direction. This produced a low-dynamicrange (LDR) image of the 3-D Mondrian scene. Second, in order to make a high-dynamic range (HDR) image of the same objects, we used a directional 150W spotlight and an array of WLEDs assembled in a flashlight. The scenes were significant as each contained exactly the same three-dimensional painted colour blocks that were arranged in the same position in the still life. The blocks comprised 6 hue colours and 5 tones from white to black. Participants from the CREATE project were asked to consider the change in the appearance of a selection of colours according to lightness, hue, and chroma, and to rate how the change in illumination affected appearance. We measured the light coming to the eye from still-life surfaces with a colorimeter (Yxy). We captured the scene radiance using multiple exposures with a number of different cameras. We have begun a programme of digital image processing of these scene capture methods. This multi-disciplinary programme continues until 2010, so this paper is an interim report on the initial phases and a description of the ongoing project.

  10. Design of the multiwavelength Scophony infrared scene projector

    Science.gov (United States)

    Thompson, Kevin P.; Kircher, James R.; Marlow, Steven A.; Korniski, Ronald J.; Richwine, Robert A.

    1993-11-01

    An all acousto-optic infrared scene projector (IRSP) has been developed for use in evaluating thermal-imaging guidance systems at the Kinetic Kill Vehicle Hardware-in-the-Loop Simulator (KHILS) facility located at Elgin AFB, Florida. The IRSP is a laser source based projector incorporating Scophony illumination and scanning methods to produce 96 X 96 pixel multi-wavelength images at very high frame rates (400 Hz). The IRSP is composed of five functionally similar optical trains, four of which are fed with a different `color' infrared laser. The separate scenes from each optical train are then combined and projected simultaneously into the imaging guidance system.

  11. Improved content aware scene retargeting for retinitis pigmentosa patients

    Directory of Open Access Journals (Sweden)

    Al-Atabany Walid I

    2010-09-01

    Full Text Available Abstract Background In this paper we present a novel scene retargeting technique to reduce the visual scene while maintaining the size of the key features. The algorithm is scalable to implementation onto portable devices, and thus, has potential for augmented reality systems to provide visual support for those with tunnel vision. We therefore test the efficacy of our algorithm on shrinking the visual scene into the remaining field of view for those patients. Methods Simple spatial compression of visual scenes makes objects appear further away. We have therefore developed an algorithm which removes low importance information, maintaining the size of the significant features. Previous approaches in this field have included seam carving, which removes low importance seams from the scene, and shrinkability which dynamically shrinks the scene according to a generated importance map. The former method causes significant artifacts and the latter is inefficient. In this work we have developed a new algorithm, combining the best aspects of both these two previous methods. In particular, our approach is to generate a shrinkability importance map using as seam based approach. We then use it to dynamically shrink the scene in similar fashion to the shrinkability method. Importantly, we have implemented it so that it can be used in real time without prior knowledge of future frames. Results We have evaluated and compared our algorithm to the seam carving and image shrinkability approaches from a content preservation perspective and a compression quality perspective. Also our technique has been evaluated and tested on a trial included 20 participants with simulated tunnel vision. Results show the robustness of our method at reducing scenes up to 50% with minimal distortion. We also demonstrate efficacy in its use for those with simulated tunnel vision of 22 degrees of field of view or less. Conclusions Our approach allows us to perform content aware video

  12. Recognizing the Stranger: Recognition Scenes in the Gospel of John

    DEFF Research Database (Denmark)

    Larsen, Kasper Bro

    Recognizing the Stranger is the first monographic study of recognition scenes and motifs in the Gospel of John. The recognition type-scene (anagnōrisis) was a common feature in ancient drama and narrative, highly valued by Aristotle as a touching moment of truth, e.g., in Oedipus’ tragic self......-discovery and Odysseus’ happy homecoming. The book offers a reconstruction of the conventions of the genre and argues that it is one of the most recurrent and significant literary forms in the Gospel. When portraying Jesus as the divine stranger from heaven, the Gospel employs and transforms the formal and ideological...

  13. Cortical Representations of Speech in a Multitalker Auditory Scene.

    Science.gov (United States)

    Puvvada, Krishna C; Simon, Jonathan Z

    2017-09-20

    The ability to parse a complex auditory scene into perceptual objects is facilitated by a hierarchical auditory system. Successive stages in the hierarchy transform an auditory scene of multiple overlapping sources, from peripheral tonotopically based representations in the auditory nerve, into perceptually distinct auditory-object-based representations in the auditory cortex. Here, using magnetoencephalography recordings from men and women, we investigate how a complex acoustic scene consisting of multiple speech sources is represented in distinct hierarchical stages of the auditory cortex. Using systems-theoretic methods of stimulus reconstruction, we show that the primary-like areas in the auditory cortex contain dominantly spectrotemporal-based representations of the entire auditory scene. Here, both attended and ignored speech streams are represented with almost equal fidelity, and a global representation of the full auditory scene with all its streams is a better candidate neural representation than that of individual streams being represented separately. We also show that higher-order auditory cortical areas, by contrast, represent the attended stream separately and with significantly higher fidelity than unattended streams. Furthermore, the unattended background streams are more faithfully represented as a single unsegregated background object rather than as separated objects. Together, these findings demonstrate the progression of the representations and processing of a complex acoustic scene up through the hierarchy of the human auditory cortex.SIGNIFICANCE STATEMENT Using magnetoencephalography recordings from human listeners in a simulated cocktail party environment, we investigate how a complex acoustic scene consisting of multiple speech sources is represented in separate hierarchical stages of the auditory cortex. We show that the primary-like areas in the auditory cortex use a dominantly spectrotemporal-based representation of the entire auditory

  14. Scene data fusion: Real-time standoff volumetric gamma-ray imaging

    Energy Technology Data Exchange (ETDEWEB)

    Barnowski, Ross [Department of Nuclear Engineering, UC Berkeley, 4155 Etcheverry Hall, MC 1730, Berkeley, CA 94720, United States of America (United States); Haefner, Andrew; Mihailescu, Lucian [Lawrence Berkeley National Lab - Applied Nuclear Physics, 1 Cyclotron Road, Berkeley, CA 94720, United States of America (United States); Vetter, Kai [Department of Nuclear Engineering, UC Berkeley, 4155 Etcheverry Hall, MC 1730, Berkeley, CA 94720, United States of America (United States); Lawrence Berkeley National Lab - Applied Nuclear Physics, 1 Cyclotron Road, Berkeley, CA 94720, United States of America (United States)

    2015-11-11

    An approach to gamma-ray imaging has been developed that enables near real-time volumetric (3D) imaging of unknown environments thus improving the utility of gamma-ray imaging for source-search and radiation mapping applications. The approach, herein dubbed scene data fusion (SDF), is based on integrating mobile radiation imagers with real-time tracking and scene reconstruction algorithms to enable a mobile mode of operation and 3D localization of gamma-ray sources. A 3D model of the scene, provided in real-time by a simultaneous localization and mapping (SLAM) algorithm, is incorporated into the image reconstruction reducing the reconstruction time and improving imaging performance. The SDF concept is demonstrated in this work with a Microsoft Kinect RGB-D sensor, a real-time SLAM solver, and a cart-based Compton imaging platform comprised of two 3D position-sensitive high purity germanium (HPGe) detectors. An iterative algorithm based on Compton kinematics is used to reconstruct the gamma-ray source distribution in all three spatial dimensions. SDF advances the real-world applicability of gamma-ray imaging for many search, mapping, and verification scenarios by improving the tractiblity of the gamma-ray image reconstruction and providing context for the 3D localization of gamma-ray sources within the environment in real-time.

  15. Scene data fusion: Real-time standoff volumetric gamma-ray imaging

    Science.gov (United States)

    Barnowski, Ross; Haefner, Andrew; Mihailescu, Lucian; Vetter, Kai

    2015-11-01

    An approach to gamma-ray imaging has been developed that enables near real-time volumetric (3D) imaging of unknown environments thus improving the utility of gamma-ray imaging for source-search and radiation mapping applications. The approach, herein dubbed scene data fusion (SDF), is based on integrating mobile radiation imagers with real-time tracking and scene reconstruction algorithms to enable a mobile mode of operation and 3D localization of gamma-ray sources. A 3D model of the scene, provided in real-time by a simultaneous localization and mapping (SLAM) algorithm, is incorporated into the image reconstruction reducing the reconstruction time and improving imaging performance. The SDF concept is demonstrated in this work with a Microsoft Kinect RGB-D sensor, a real-time SLAM solver, and a cart-based Compton imaging platform comprised of two 3D position-sensitive high purity germanium (HPGe) detectors. An iterative algorithm based on Compton kinematics is used to reconstruct the gamma-ray source distribution in all three spatial dimensions. SDF advances the real-world applicability of gamma-ray imaging for many search, mapping, and verification scenarios by improving the tractiblity of the gamma-ray image reconstruction and providing context for the 3D localization of gamma-ray sources within the environment in real-time.

  16. Visual Object Recognition with 3D-Aware Features in KITTI Urban Scenes.

    Science.gov (United States)

    Yebes, J Javier; Bergasa, Luis M; García-Garrido, Miguel Ángel

    2015-04-20

    Driver assistance systems and autonomous robotics rely on the deployment of several sensors for environment perception. Compared to LiDAR systems, the inexpensive vision sensors can capture the 3D scene as perceived by a driver in terms of appearance and depth cues. Indeed, providing 3D image understanding capabilities to vehicles is an essential target in order to infer scene semantics in urban environments. One of the challenges that arises from the navigation task in naturalistic urban scenarios is the detection of road participants (e.g., cyclists, pedestrians and vehicles). In this regard, this paper tackles the detection and orientation estimation of cars, pedestrians and cyclists, employing the challenging and naturalistic KITTI images. This work proposes 3D-aware features computed from stereo color images in order to capture the appearance and depth peculiarities of the objects in road scenes. The successful part-based object detector, known as DPM, is extended to learn richer models from the 2.5D data (color and disparity), while also carrying out a detailed analysis of the training pipeline. A large set of experiments evaluate the proposals, and the best performing approach is ranked on the KITTI website. Indeed, this is the first work that reports results with stereo data for the KITTI object challenge, achieving increased detection ratios for the classes car and cyclist compared to a baseline DPM.

  17. Visual Object Recognition with 3D-Aware Features in KITTI Urban Scenes

    Directory of Open Access Journals (Sweden)

    J. Javier Yebes

    2015-04-01

    Full Text Available Driver assistance systems and autonomous robotics rely on the deployment of several sensors for environment perception. Compared to LiDAR systems, the inexpensive vision sensors can capture the 3D scene as perceived by a driver in terms of appearance and depth cues. Indeed, providing 3D image understanding capabilities to vehicles is an essential target in order to infer scene semantics in urban environments. One of the challenges that arises from the navigation task in naturalistic urban scenarios is the detection of road participants (e.g., cyclists, pedestrians and vehicles. In this regard, this paper tackles the detection and orientation estimation of cars, pedestrians and cyclists, employing the challenging and naturalistic KITTI images. This work proposes 3D-aware features computed from stereo color images in order to capture the appearance and depth peculiarities of the objects in road scenes. The successful part-based object detector, known as DPM, is extended to learn richer models from the 2.5D data (color and disparity, while also carrying out a detailed analysis of the training pipeline. A large set of experiments evaluate the proposals, and the best performing approach is ranked on the KITTI website. Indeed, this is the first work that reports results with stereo data for the KITTI object challenge, achieving increased detection ratios for the classes car and cyclist compared to a baseline DPM.

  18. "But the moment they find out that you are MSM…": a qualitative investigation of HIV prevention experiences among men who have sex with men (MSM) in Ghana's health care system.

    Science.gov (United States)

    Kushwaha, Sameer; Lalani, Yasmin; Maina, Geoffrey; Ogunbajo, Adedotun; Wilton, Leo; Agyarko-Poku, Thomas; Adu-Sarkodie, Yaw; Boakye, Francis; Zhang, Nanhua; Nelson, LaRon E

    2017-10-03

    The prevalence of HIV in Ghana is 1.3%, compared to 17% among men who have sex with men (MSM). There is limited empirical data on the current health care climate and its impact on HIV prevention services for Ghanaian MSM. The purposes of this study were to investigate (1) MSM's experiences using HIV prevention resources, (2) what factors, including health care climate factors, influenced MSM's use of prevention resources and (3) MSM self-identified strategies for improving HIV/sexually transmitted infection (STI) prevention among MSM in Ghanaian communities. We conducted 22 focus groups (n = 137) with peer social networks of MSM drawn from three geographic communities in Ghana (Accra, Kumasi, Manya Krobo). The data were examined using qualitative content analysis. Interviews with individual health care providers were also conducted to supplement the analysis of focus group findings to provide more nuanced illuminations of the experiences reported by MSM. There were four major findings related to MSM experiences using HIV prevention resources: (1) condom quality is low, condom access is poor, and condom use is disruptive, (2) inaccurate information undermines HIV testing (3), stigma undermines HIV testing, and (4) positive attitudes towards HIV prevention exist among MSM. The main healthcare climate factors that affected prevention were that MSM were not free to be themselves, MSM were not understood by healthcare providers, and that MSM did not feel that healthcare providers cared about them. To improve HIV prevention MSM suggested increased education tailored to MSM should be provided to enable self-advocacy and that education and awareness are needed to protect human rights of MSM in Ghana. MSM in Ghana are exposed to negative health care climates. Health care spaces that are unsupportive of MSM's autonomy undermine the uptake of prevention measures such as condoms, HIV testing, and accurate sexual health education. These findings contribute to knowledge to

  19. Gestalt-like constraints produce veridical (Euclidean) percepts of 3D indoor scenes.

    Science.gov (United States)

    Kwon, TaeKyu; Li, Yunfeng; Sawada, Tadamasa; Pizlo, Zygmunt

    2016-09-01

    This study, which was influenced a lot by Gestalt ideas, extends our prior work on the role of a priori constraints in the veridical perception of 3D shapes to the perception of 3D scenes. Our experiments tested how human subjects perceive the layout of a naturally-illuminated indoor scene that contains common symmetrical 3D objects standing on a horizontal floor. In one task, the subject was asked to draw a top view of a scene that was viewed either monocularly or binocularly. The top views the subjects reconstructed were configured accurately except for their overall size. These size errors varied from trial to trial, and were shown most-likely to result from the presence of a response bias. There was little, if any, evidence of systematic distortions of the subjects' perceived visual space, the kind of distortions that have been reported in numerous experiments run under very unnatural conditions. This shown, we proceeded to use Foley's (Vision Research 12 (1972) 323-332) isosceles right triangle experiment to test the intrinsic geometry of visual space directly. This was done with natural viewing, with the impoverished viewing conditions Foley had used, as well as with a number of intermediate viewing conditions. Our subjects produced very accurate triangles when the viewing conditions were natural, but their performance deteriorated systematically as the viewing conditions were progressively impoverished. Their perception of visual space became more compressed as their natural visual environment was degraded. Once this was shown, we developed a computational model that emulated the most salient features of our psychophysical results. We concluded that human observers see 3D scenes veridically when they view natural 3D objects within natural 3D environments. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  20. Risk factors for anal high-grade squamous intraepithelial lesions in HIV-positive MSM: is targeted screening possible?

    Science.gov (United States)

    Siegenbeek van Heukelom, Matthijs L; Marra, Elske; de Vries, Henry J C; Schim van der Loeff, Maarten F; Prins, Jan M

    2017-10-23

    HIV-positive MSM are at increased risk for developing anal squamous cell carcinoma. Detection of precursor lesions of anal cancer [anal high-grade squamous intraepithelial lesions (HSIL)] is cumbersome and expensive. Our objective was to identify potential risk factors for anal HSIL in HIV-positive MSM to develop more stringent screening criteria. We studied a cohort of MSM screened by high-resolution anoscopy at three HIV clinics in Amsterdam, the Netherlands. For every first high-resolution anoscopy performed in a patient, we analyzed five demographic and seven HIV-related potential risk factors for four different outcome measures: histologically proven anal HSIL vs. no squamous intraepithelial lesions (SIL), HSIL-anal intraepithelial neoplasia 2 vs. no SIL, HSIL-anal intraepithelial neoplasia 3 vs. no SIL, and HSIL vs. no HSIL. We used univariable and multilevel, multivariable logistic regression. From 2008 through 2015, 497 out of 1678 (30%) screened HIV-positive MSM had anal HSIL. The mean age was 49 years (SD 9.6), 96% used combination antiretroviral therapy, and median duration of combination antiretroviral therapy use was 7.8 years (interquartile range 4.0-12.4). Increasing age [adjusted odds ratio (aOR) 0.82, 95% confidence interval (CI) 0.70-0.94, P = 0.006] and years living with suppressed viral load [1-5 years suppressed aOR 0.52 (95% CI 0.34-0.80), 5.01-10 years aOR 0.47 (95% CI 0.29-0.74), >10 years aOR 0.54 [0.34-0.87], all compared to less than 1 year suppressed, P = 0.009] were found to be protective for HSIL vs. no SIL. Young HIV-positive MSM without viral suppression are statistically at highest risk for anal HSIL, but given the high prevalence among all virally suppressed men, we advise that all HIV-positive MSM should be screened for HSIL.

  1. Risk factors for anal high-grade squamous intraepithelial lesions in HIV-positive MSM: is targeted screening possible?

    Science.gov (United States)

    Siegenbeek van Heukelom, Matthijs L.; Marra, Elske; de Vries, Henry J.C.; van der Loeff, Maarten F. Schim; Prins, Jan M.

    2017-01-01

    Objective: HIV-positive MSM are at increased risk for developing anal squamous cell carcinoma. Detection of precursor lesions of anal cancer [anal high-grade squamous intraepithelial lesions (HSIL)] is cumbersome and expensive. Our objective was to identify potential risk factors for anal HSIL in HIV-positive MSM to develop more stringent screening criteria. Design: We studied a cohort of MSM screened by high-resolution anoscopy at three HIV clinics in Amsterdam, the Netherlands. Methods: For every first high-resolution anoscopy performed in a patient, we analyzed five demographic and seven HIV-related potential risk factors for four different outcome measures: histologically proven anal HSIL vs. no squamous intraepithelial lesions (SIL), HSIL-anal intraepithelial neoplasia 2 vs. no SIL, HSIL-anal intraepithelial neoplasia 3 vs. no SIL, and HSIL vs. no HSIL. We used univariable and multilevel, multivariable logistic regression. Results: From 2008 through 2015, 497 out of 1678 (30%) screened HIV-positive MSM had anal HSIL. The mean age was 49 years (SD 9.6), 96% used combination antiretroviral therapy, and median duration of combination antiretroviral therapy use was 7.8 years (interquartile range 4.0–12.4). Increasing age [adjusted odds ratio (aOR) 0.82, 95% confidence interval (CI) 0.70–0.94, P = 0.006] and years living with suppressed viral load [1–5 years suppressed aOR 0.52 (95% CI 0.34–0.80), 5.01–10 years aOR 0.47 (95% CI 0.29–0.74), >10 years aOR 0.54 [0.34–0.87], all compared to less than 1 year suppressed, P = 0.009] were found to be protective for HSIL vs. no SIL. Conclusion: Young HIV-positive MSM without viral suppression are statistically at highest risk for anal HSIL, but given the high prevalence among all virally suppressed men, we advise that all HIV-positive MSM should be screened for HSIL. PMID:28991027

  2. How saliency, faces, and sound influence gaze in dynamic social scenes.

    Science.gov (United States)

    Coutrot, Antoine; Guyader, Nathalie

    2014-07-03

    Conversation scenes are a typical example in which classical models of visual attention dramatically fail to predict eye positions. Indeed, these models rarely consider faces as particular gaze attractors and never take into account the important auditory information that always accompanies dynamic social scenes. We recorded the eye movements of participants viewing dynamic conversations taking place in various contexts. Conversations were seen either with their original soundtracks or with unrelated soundtracks (unrelated speech and abrupt or continuous natural sounds). First, we analyze how auditory conditions influence the eye movement parameters of participants. Then, we model the probability distribution of eye positions across each video frame with a statistical method (Expectation-Maximization), allowing the relative contribution of different visual features such as static low-level visual saliency (based on luminance contrast), dynamic low level visual saliency (based on motion amplitude), faces, and center bias to be quantified. Through experimental and modeling results, we show that regardless of the auditory condition, participants look more at faces, and especially at talking faces. Hearing the original soundtrack makes participants follow the speech turn-taking more closely. However, we do not find any difference between the different types of unrelated soundtracks. These eyetracking results are confirmed by our model that shows that faces, and particularly talking faces, are the features that best explain the gazes recorded, especially in the original soundtrack condition. Low-level saliency is not a relevant feature to explain eye positions made on social scenes, even dynamic ones. Finally, we propose groundwork for an audiovisual saliency model. © 2014 ARVO.

  3. Text-Attentional Convolutional Neural Network for Scene Text Detection.

    Science.gov (United States)

    He, Tong; Huang, Weilin; Qiao, Yu; Yao, Jian

    2016-06-01

    Recent deep learning models have demonstrated strong capabilities for classifying text and non-text components in natural images. They extract a high-level feature globally computed from a whole image component (patch), where the cluttered background information may dominate true text features in the deep representation. This leads to less discriminative power and poorer robustness. In this paper, we present a new system for scene text detection by proposing a novel text-attentional convolutional neural network (Text-CNN) that particularly focuses on extracting text-related regions and features from the image components. We develop a new learning mechanism to train the Text-CNN with multi-level and rich supervised information, including text region mask, character label, and binary text/non-text information. The rich supervision information enables the Text-CNN with a strong capability for discriminating ambiguous texts, and also increases its robustness against complicated background components. The training process is formulated as a multi-task learning problem, where low-level supervised information greatly facilitates the main task of text/non-text classification. In addition, a powerful low-level detector called contrast-enhancement maximally stable extremal regions (MSERs) is developed, which extends the widely used MSERs by enhancing intensity contrast between text patterns and background. This allows it to detect highly challenging text patterns, resulting in a higher recall. Our approach achieved promising results on the ICDAR 2013 data set, with an F-measure of 0.82, substantially improving the state-of-the-art results.

  4. Text-Attentional Convolutional Neural Networks for Scene Text Detection.

    Science.gov (United States)

    He, Tong; Huang, Weilin; Qiao, Yu; Yao, Jian

    2016-03-28

    Recent deep learning models have demonstrated strong capabilities for classifying text and non-text components in natural images. They extract a high-level feature computed globally from a whole image component (patch), where the cluttered background information may dominate true text features in the deep representation. This leads to less discriminative power and poorer robustness. In this work, we present a new system for scene text detection by proposing a novel Text-Attentional Convolutional Neural Network (Text-CNN) that particularly focuses on extracting text-related regions and features from the image components. We develop a new learning mechanism to train the Text-CNN with multi-level and rich supervised information, including text region mask, character label, and binary text/nontext information. The rich supervision information enables the Text-CNN with a strong capability for discriminating ambiguous texts, and also increases its robustness against complicated background components. The training process is formulated as a multi-task learning problem, where low-level supervised information greatly facilitates main task of text/non-text classification. In addition, a powerful low-level detector called Contrast- Enhancement Maximally Stable Extremal Regions (CE-MSERs) is developed, which extends the widely-used MSERs by enhancing intensity contrast between text patterns and background. This allows it to detect highly challenging text patterns, resulting in a higher recall. Our approach achieved promising results on the ICDAR 2013 dataset, with a F-measure of 0.82, improving the state-of-the-art results substantially.

  5. Ontology of a scene based on Java 3D architecture.

    Directory of Open Access Journals (Sweden)

    Rubén González Crespo

    2009-12-01

    Full Text Available The present article seeks to make an approach to the class hierarchy of a scene built with the architecture Java 3D, to develop an ontology of a scene as from the semantic essential components for the semantic structuring of the Web3D. Java was selected because the language recommended by the W3C Consortium for the Development of the Web3D oriented applications as from X3D standard is Xj3D which compositionof their Schemas is based the architecture of Java3D In first instance identifies the domain and scope of the ontology, defining classes and subclasses that comprise from Java3D architecture and the essential elements of a scene, as its point of origin, the field of rotation, translation The limitation of the scene and the definition of shaders, then define the slots that are declared in RDF as a framework for describing the properties of the classes established from identifying thedomain and range of each class, then develops composition of the OWL ontology on SWOOP Finally, be perform instantiations of the ontology building for a Iconosphere object as from class expressions defined.

  6. Understanding road scenes using visual cues and GPS information

    NARCIS (Netherlands)

    Alvarez, J.M.; Lumbreras, F.; Lopez, A.M.; Gevers, T.

    2012-01-01

    Understanding road scenes is important in computer vision with different applications to improve road safety (e.g., advanced driver assistance systems) and to develop autonomous driving systems (e.g., Google driver-less vehicle). Current vision-based approaches rely on the robust combination of

  7. Words Matter: Scene Text for Image Classification and Retrieval

    NARCIS (Netherlands)

    Karaoglu, S.; Tao, R.; Gevers, T.; Smeulders, A.W.M.

    Text in natural images typically adds meaning to an object or scene. In particular, text specifies which business places serve drinks (e.g., cafe, teahouse) or food (e.g., restaurant, pizzeria), and what kind of service is provided (e.g., massage, repair). The mere presence of text, its words, and

  8. The value of DNA material recovered from crime scenes.

    Science.gov (United States)

    Bond, John W; Hammond, Christine

    2008-07-01

    DNA material is now collected routinely from crime scenes for a wide range of offenses and its timely processing is acknowledged as a key element to its success in solving crime. An analysis of the processing of approximately 1500 samples of DNA material recovered from the property crime offenses of residential burglary, commercial burglary, and theft of motor vehicle in Northamptonshire, U.K. during 2006 identified saliva and cigarette ends as the main sources of DNA recovered (approximately 63% of samples) with blood, cellular DNA, and chewing gum accounting for the remainder. The conversion of these DNA samples into DNA profiles and then into matches with offender profiles held on the U.K. National DNA database is considered in terms of the ease with which Crime Scene Examiners can recover DNA rich samples of different sources, the location of the DNA at the crime scene, and its mobility. A logistical regression of the DNA material recovered has revealed a number of predictors, other than timeliness, that greatly influence its conversion into a DNA profile. The most significant predictor was found to be Crime Scene Examiner accreditation with offense type and DNA sample condition also being relevant. A similar logistical regression of DNA samples profiled that produced a match with an offender on the U.K. National DNA database showed no significance with any of the predictors considered.

  9. Fuzzy Emotional Semantic Analysis and Automated Annotation of Scene Images

    Directory of Open Access Journals (Sweden)

    Jianfang Cao

    2015-01-01

    Full Text Available With the advances in electronic and imaging techniques, the production of digital images has rapidly increased, and the extraction and automated annotation of emotional semantics implied by images have become issues that must be urgently addressed. To better simulate human subjectivity and ambiguity for understanding scene images, the current study proposes an emotional semantic annotation method for scene images based on fuzzy set theory. A fuzzy membership degree was calculated to describe the emotional degree of a scene image and was implemented using the Adaboost algorithm and a back-propagation (BP neural network. The automated annotation method was trained and tested using scene images from the SUN Database. The annotation results were then compared with those based on artificial annotation. Our method showed an annotation accuracy rate of 91.2% for basic emotional values and 82.4% after extended emotional values were added, which correspond to increases of 5.5% and 8.9%, respectively, compared with the results from using a single BP neural network algorithm. Furthermore, the retrieval accuracy rate based on our method reached approximately 89%. This study attempts to lay a solid foundation for the automated emotional semantic annotation of more types of images and therefore is of practical significance.

  10. Cultural heritage and history in the European metal scene

    NARCIS (Netherlands)

    Klepper, de S.; Molpheta, S.; Pille, S.; Saouma, R.; During, R.; Muilwijk, M.

    2007-01-01

    This paper represents an inquiry on the use of history and cultural heritage in the metal scene. It is an attempt to show how history and cultural heritage can possibly be spread among people using an unconventional way. The followed research method was built on an explorative study that included an

  11. Semantic control of feature extraction from natural scenes.

    Science.gov (United States)

    Neri, Peter

    2014-02-05

    In the early stages of image analysis, visual cortex represents scenes as spatially organized maps of locally defined features (e.g., edge orientation). As image reconstruction unfolds and features are assembled into larger constructs, cortex attempts to recover semantic content for object recognition. It is conceivable that higher level representations may feed back onto early processes and retune their properties to align with the semantic structure projected by the scene; however, there is no clear evidence to either support or discard the applicability of this notion to the human visual system. Obtaining such evidence is challenging because low and higher level processes must be probed simultaneously within the same experimental paradigm. We developed a methodology that targets both levels of analysis by embedding low-level probes within natural scenes. Human observers were required to discriminate probe orientation while semantic interpretation of the scene was selectively disrupted via stimulus inversion or reversed playback. We characterized the orientation tuning properties of the perceptual process supporting probe discrimination; tuning was substantially reshaped by semantic manipulation, demonstrating that low-level feature detectors operate under partial control from higher level modules. The manner in which such control was exerted may be interpreted as a top-down predictive strategy whereby global semantic content guides and refines local image reconstruction. We exploit the novel information gained from data to develop mechanistic accounts of unexplained phenomena such as the classic face inversion effect.

  12. Towards Unsupervised Familiar Scene Recognition in Egocentric Videos

    NARCIS (Netherlands)

    Talavera Martínez, Estefanía

    2015-01-01

    Nowadays, there is an upsurge of interest in using lifelogging devices. Such devices generate huge amounts of image data; consequently, the need for automatic methods for analyzing and summarizing these data is drastically increasing. We present a new method for familiar scene recognition in

  13. The role of memory for visual search in scenes

    Science.gov (United States)

    Võ, Melissa Le-Hoa; Wolfe, Jeremy M.

    2014-01-01

    Many daily activities involve looking for something. The ease with which these searches are performed often allows one to forget that searching represents complex interactions between visual attention and memory. While a clear understanding exists of how search efficiency will be influenced by visual features of targets and their surrounding distractors or by the number of items in the display, the role of memory in search is less well understood. Contextual cueing studies have shown that implicit memory for repeated item configurations can facilitate search in artificial displays. When searching more naturalistic environments, other forms of memory come into play. For instance, semantic memory provides useful information about which objects are typically found where within a scene, and episodic scene memory provides information about where a particular object was seen the last time a particular scene was viewed. In this paper, we will review work on these topics, with special emphasis on the role of memory in guiding search in organized, real-world scenes. PMID:25684693

  14. The role of memory for visual search in scenes.

    Science.gov (United States)

    Le-Hoa Võ, Melissa; Wolfe, Jeremy M

    2015-03-01

    Many daily activities involve looking for something. The ease with which these searches are performed often allows one to forget that searching represents complex interactions between visual attention and memory. Although a clear understanding exists of how search efficiency will be influenced by visual features of targets and their surrounding distractors or by the number of items in the display, the role of memory in search is less well understood. Contextual cueing studies have shown that implicit memory for repeated item configurations can facilitate search in artificial displays. When searching more naturalistic environments, other forms of memory come into play. For instance, semantic memory provides useful information about which objects are typically found where within a scene, and episodic scene memory provides information about where a particular object was seen the last time a particular scene was viewed. In this paper, we will review work on these topics, with special emphasis on the role of memory in guiding search in organized, real-world scenes. © 2015 New York Academy of Sciences.

  15. Fuzzy emotional semantic analysis and automated annotation of scene images.

    Science.gov (United States)

    Cao, Jianfang; Chen, Lichao

    2015-01-01

    With the advances in electronic and imaging techniques, the production of digital images has rapidly increased, and the extraction and automated annotation of emotional semantics implied by images have become issues that must be urgently addressed. To better simulate human subjectivity and ambiguity for understanding scene images, the current study proposes an emotional semantic annotation method for scene images based on fuzzy set theory. A fuzzy membership degree was calculated to describe the emotional degree of a scene image and was implemented using the Adaboost algorithm and a back-propagation (BP) neural network. The automated annotation method was trained and tested using scene images from the SUN Database. The annotation results were then compared with those based on artificial annotation. Our method showed an annotation accuracy rate of 91.2% for basic emotional values and 82.4% after extended emotional values were added, which correspond to increases of 5.5% and 8.9%, respectively, compared with the results from using a single BP neural network algorithm. Furthermore, the retrieval accuracy rate based on our method reached approximately 89%. This study attempts to lay a solid foundation for the automated emotional semantic annotation of more types of images and therefore is of practical significance.

  16. Logical unit and scene detection: a comparative survey

    Science.gov (United States)

    Petersohn, Christian

    2008-01-01

    Logical units are semantic video segments above the shot level. Depending on the common semantics within the unit and data domain, different types of logical unit extraction algorithms have been presented in literature. Topic units are typically extracted for documentaries or news broadcasts while scenes are extracted for narrative-driven video such as feature films, sitcoms, or cartoons. Other types of logical units are extracted from home video and sports. Different algorithms in literature used for the extraction of logical units are reviewed in this paper based on the categories unit type, data domain, features used, segmentation method, and thresholds applied. A detailed comparative study is presented for the case of extracting scenes from narrative-driven video. While earlier comparative studies focused on scene segmentation methods only or on complete news-story segmentation algorithms, in this paper various visual features and segmentation methods with their thresholding mechanisms and their combination into complete scene detection algorithms are investigated. The performance of the resulting large set of algorithms is then evaluated on a set of video files including feature films, sitcoms, children's shows, a detective story, and cartoons.

  17. Coping with Perceived Ethnic Prejudice on the Gay Scene

    Science.gov (United States)

    Jaspal, Rusi

    2017-01-01

    There has been only cursory research into the sociological and psychological aspects of ethnic/racial discrimination among ethnic minority gay and bisexual men, and none that focuses specifically upon British ethnic minority gay men. This article focuses on perceptions of intergroup relations on the gay scene among young British South Asian gay…

  18. Automatic video surveillance of outdoor scenes using track before detect

    DEFF Research Database (Denmark)

    Hansen, Morten; Sørensen, Helge Bjarup Dissing; Birkemark, Christian M.

    2005-01-01

    This paper concerns automatic video surveillance of outdoor scenes using a single camera. The first step in automatic interpretation of the video stream is activity detection based on background subtraction. Usually, this process will generate a large number of false alarms in outdoor scenes due ...... if a detected object shows a pattern of movement consistent with predefined rules. The method is tested on a number of video sequences and a substantial reduction in the number of false alarms is demonstrated.......This paper concerns automatic video surveillance of outdoor scenes using a single camera. The first step in automatic interpretation of the video stream is activity detection based on background subtraction. Usually, this process will generate a large number of false alarms in outdoor scenes due...... to e.g. movement of thicket and changes in illumination. To reduce the number of false alarms a Track Before Detect (TBD) approach is suggested. In this TBD implementation all objects detected in the background subtraction process are followed over a number of frames. An alarm is given only...

  19. The Rescue Mission: Assigning Guilt to a Chaotic Scene.

    Science.gov (United States)

    Procter, David E.

    1987-01-01

    Seeks to identify rhetorical distinctiveness of the rescue mission as a form of belligerency--examining presidential discourse justifying the 1985 Lebanon intervention, the 1965 Dominican intervention, and the 1983 Grenada intervention. Argues that the distinction is in guilt narrowly assigned to a chaotic scene and the concomitant call for…

  20. Range and intensity vision for rock-scene segmentation

    CSIR Research Space (South Africa)

    Mkwelo, SG

    2007-11-01

    Full Text Available This paper presents another approach to segmenting a scene of rocks on a conveyor belt for the purposes of measuring rock size. Rock size estimation instruments are used to monitor, optimize and control milling and crushing in the mining industry...

  1. 3-D Scene Generation On A Shared Memory Parallel Processor

    Science.gov (United States)

    Kelly, R. F.

    1987-06-01

    Realistic 3-D scene generation is now a possibility for many applications. One barrier to increased use of this technique is the large amount of computer processing time needed to render a scene. With the advent of parallel processors that barrier may be overcome if efficient parallel scene generation algorithms can be developed. In general, this has not been true because of restrictions imposed by non-shared memory and limited processor interconnect architectures. In addition, vector processors do not efficiently support the adaptive nature of many of the algorithms. A new parallel computer, the NYU Ultracomputer, has been developed which features a shared memory with a combining network. The com-bining network permits simultaneous reads and writes to the same memory location using a new instruction the Fetch and_Op. These memory references are resolved in the memory access network and result in particularly efficient shared data structures. Basic elements of this architecture are also being used in the design of the gigaflop range RP3 at IBM. Some algorithms typical of image synthesis are explored in the paper and a class of equivalent queue based algorithms are developed. These algorithms are particularly well suited to the Ultra-computer class processor and hold the promise for many new applications of realistic scene generation.

  2. Scene Context Dependency of Pattern Constancy of Time Series Imagery

    Science.gov (United States)

    Woodell, Glenn A.; Jobson, Daniel J.; Rahman, Zia-ur

    2008-01-01

    A fundamental element of future generic pattern recognition technology is the ability to extract similar patterns for the same scene despite wide ranging extraneous variables, including lighting, turbidity, sensor exposure variations, and signal noise. In the process of demonstrating pattern constancy of this kind for retinex/visual servo (RVS) image enhancement processing, we found that the pattern constancy performance depended somewhat on scene content. Most notably, the scene topography and, in particular, the scale and extent of the topography in an image, affects the pattern constancy the most. This paper will explore these effects in more depth and present experimental data from several time series tests. These results further quantify the impact of topography on pattern constancy. Despite this residual inconstancy, the results of overall pattern constancy testing support the idea that RVS image processing can be a universal front-end for generic visual pattern recognition. While the effects on pattern constancy were significant, the RVS processing still does achieve a high degree of pattern constancy over a wide spectrum of scene content diversity, and wide ranging extraneousness variations in lighting, turbidity, and sensor exposure.

  3. FABRICATION, MORPHOLOGICAL AND OPTOELECTRONIC PROPERTIES OF ANTIMONY ON POROUS SILICON AS MSM PHOTODETECTOR

    Directory of Open Access Journals (Sweden)

    H. A. Hadi

    2014-12-01

    Full Text Available We report on the fabrication and characterization of MSM photodetector. We investigated the surface morphological and the structural properties of the porous silicon by optical microscopy, atomic force microscope (AFM and X-ray diffraction. The metal–semiconductor–metal photodetector were fabricated by using Sb as Schottky contact metal.The junction exhibits good rectification ratio of 105 at bias of 2V. A large photocurrent to dark-current contrast ratio higher than 55 orders of magnitude and low dark currents below 0.89 nA .High responsivity of 0.225A/W at 400 nm and 0.15 A/W at 400 and 700nm were observed at an operating bias of less than -2 V, corresponding quantum efficiency of 70% and 26% respectively. The lifetimes are evaluated using OCVD method and the carrier life time is 100 μs. The results show that Sb on porous silicon (PS structures will act as good candidates for making highly efficient photodiodes.

  4. Are Thai MSM willing to take PrEP for HIV prevention? An analysis of attitudes, preferences and acceptance.

    Directory of Open Access Journals (Sweden)

    Ana Wheelock

    Full Text Available We aimed to understand the attitudes, preferences and acceptance of oral and parenteral PrEP among men who have sex with men (MSM in Thailand.Pre-exposure prophylaxis (PrEP, the use of antiretrovirals to prevent HIV acquisition, has shown promising results in recent trials. To assess the potential impact of this new HIV prevention method, in addition to efficacy data, we need to understand which psychosocial factors are likely to determine its uptake among members of potential user groups.Surveys of willingness to use PrEP products were administered to MSM. Spearman's rank tests were used to uncover associations between questionnaire items. Mann-Whitney tests were performed to ascertain differences between groups. Conjoint analysis was used to examine the attitudes and preferences of MSM towards PrEP attributes. Most participants were willing to consider taking PrEP (39.2% "yes, definitely" and 49.2% "yes, probably" and perceived PrEP as giving them new possibilities in their lives (38.5% "a lot of hope" and 55.8% "some hope", even after being instructed of potential side effects and costs. HIV testing was considered the most important attribute and a daily pill and longer lasting injection in the arm were the preferred routes of administration.Despite its multiple challenges, MSM in Thailand would be willing to take PrEP, even if they had to experience inconvenience and expense. If PrEP were to be implemented in Thailand, our findings show that its uptake could be considerable.

  5. Crowdsourcing to promote HIV testing among MSM in China: study protocol for a stepped wedge randomized controlled trial.

    Science.gov (United States)

    Tucker, Joseph D

    2017-10-02

    HIV testing for marginalized populations is critical to controlling the HIV epidemic. However, the HIV testing rate among men who have sex with men (MSM) in China remains low. Crowdsourcing, the process of shifting individual tasks to a group, has been increasingly adopted in public health programs and may be a useful tool for spurring innovation in HIV testing campaigns. We designed a multi-site study to develop a crowdsourced HIV test promotion campaign and evaluate its effectiveness against conventional campaigns among MSM in China. This study will use an adaptation of the stepped wedge, randomized controlled trial design. A total of eight major metropolitan cities in China will be randomized to sequentially initiate interventions at 3-month intervals. The intervention uses crowdsourcing at multiple steps to sustain crowd contribution. Approximately 1280 MSM, who are 16 years of age or over, live in the intervention city, have not been tested for HIV in the past 3 months, and are not living with HIV, will be recruited. Recruitment will take place through banner advertisements on a large gay dating app along with other social media platforms. Participants will complete one follow-up survey every 3 months for 12 months to evaluate their HIV testing uptake in the past 3 months and secondary outcomes including syphilis testing, sex without condoms, community engagement, testing stigma, and other related outcomes. MSM HIV testing rates remain poor in China. Innovative methods to promote HIV testing are urgently needed. With a large-scale, stepped wedge, randomized controlled trial our study can improve understanding of crowdsourcing's long-term effectiveness in public health campaigns, expand HIV testing coverage among a key population, and inform intervention design in related public health fields. ClinicalTrials.gov, NCT02796963 . Registered on 23 May 2016.

  6. Sex partner meeting places over time among newly HIV diagnosed men who have sex with men (MSM) in Baltimore, Maryland

    Science.gov (United States)

    Jennings, Jacky M.; Reilly, Meredith L.; Perin, Jamie; Schumacher, Christina; Sharma, Megha; Safi, Amelia Greiner; Fields, Errol L.; Muvva, Ravikiran; Nganga-Good, Carolyn; Chaulk, Patrick

    2015-01-01

    Background Sex partner meeting places may be important locales to access men who have sex with men (MSM) and implement targeted human immunodeficiency virus (HIV) control strategies. These locales may change over time, but temporal evaluations have not been performed. Methods The objectives of this study were to describe the frequency of report of MSM sex partner meeting places over time, and to compare frequently reported meeting places in the past five years and past year among newly HIV diagnosed MSM in Baltimore City, Maryland. Public health HIV surveillance data including partner services information was obtained for this study from the Baltimore City Health Department from May 2009 to June 2014. Results 869 sex partner meeting places were reported, including 306 unique places. Bars/clubs (31%) and internet-based sites (38%) were the most frequently reported meeting place types. Over the five year period, the percentage of bars/clubs decreased over time and the percentage of internet-based sites increased over time. Among bars/clubs, 4/5 of those most frequently reported in the past five years were also most frequently reported in the most recent year. Among internet-based sites, 3/5 of those most frequently reported in the past five years were also in the top five most frequently reported in the past year. Conclusion This study provides a richer understanding of sex partner meeting places reported by MSM over time and information to health departments on types of places to access a population at high risk for HIV transmission. PMID:26372926

  7. Hepatitis A outbreak in Barcelona among men who have sex with men (MSM), January-June 2017: A hospital perspective.

    Science.gov (United States)

    Rodríguez-Tajes, Sergio; Perpiñán, Elena; Caballol, Berta; Lens, Sabela; Mariño, Zoe; Costa, Josep; Vilella, Anna; Pérez-Del-Pulgar, Sofía; Forns, Xavier; Koutsoudakis, George

    2017-10-04

    Acute hepatitis A is transmitted mainly via the faecal-oral route and/or contaminated aliment. Furthermore, several outbreaks in the men who have sex with men (MSM) population classified hepatitis A as a sexually transmitted disease (STD). We aimed to clarify an ongoing hepatitis A outbreak in Barcelona with respect to patients' characteristics and viral phylogenetic analysis. We prospectively analyzed 46 cases of hepatitis A infection that were registered in our hospital between January and June 2017. We evaluated demographics data, risk factors, presenting symptoms, sexual orientation, comorbidities and further STD infections. The phylogenetic correlation of the current circulating viruses among them and other hepatitis A strains was assessed by sequencing of the VP1/P2A region. Most patients were male (44, 96%) with median age 33.5 years (range 28-50). Thirty-one (67%) were MSM and 18 (39%) required hospitalization. Molecular phylogenetic analyses revealed that all patients were infected by hepatitis A subgenotype IA strains. Moreover, current strains comprised 3 distinct clusters, previously reported in ongoing outbreaks in the United Kingdom, Berlin and the Netherlands. However, these strains were phylogenetically diverse to those previously reported in Barcelona metropolitan region. Ongoing hepatitis A outbreak in Barcelona affects primarily the MSM community and is phylogenetically linked to current hepatitis A outbreaks described in other European countries. As a result of the high admission rate, these outbreaks may impact the admission pattern of referral liver units. Control measures, for example vaccinations programs tailored to the MSM community, must be taken to control further spreading. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  8. Photoelectric properties of MSM structure based on ZnO nanorods, received by thermal evaporation and carbothermal syntesis

    Science.gov (United States)

    Zhilin, D. A.; Lyanguzov, N. V.; Nikolaev, L. A.; Pushkariov, V. I.; Kaidashev, E. M.

    2014-10-01

    Photoelectric characteristics of metal-semiconductor-metal (MSM) structures: Au/ZnO(nanorods)/ZnO(film)/ZnO(nanorods)/Au were investigated. Synthesis of ZnO nanorods (NR's) was carried out by two different methods, such as catalyst-free carbothermal synthesis (t = 950°C, precursor - ZnO:C) and catalyst-free thermal evaporation of metallic Zn (t = 600°C, precursor Zn). Photoluminescence spectra have shown that the ZnO NR's obtained by means of thermal evaporation technique have a lower concentration of point defects related with oxygen vacancies, than ZnO NR's prepared by carbothermal synthesis. MSM structure with ZnO NR's obtained by thermal evaporation technique have photosensitivity 97 mA/W at ~ 325 nm illumination and 44 mA/W at ~ 518 nm illumination at a bias 5V. For MSM structure with ZnO NR's obtained by method of carbothermal synthesis, the photosensitivity values were 22 mA/W, and 103 mA/W, respectively.

  9. The relationship between online social networking and sexual risk behaviors among men who have sex with men (MSM.

    Directory of Open Access Journals (Sweden)

    Sean D Young

    Full Text Available Online social networking usage is growing rapidly, especially among at-risk populations, such as men who have sex with men (MSM. However, little research has studied the relationship between online social networking usage and sexual risk behaviors among at-risk populations. One hundred and eighteen Facebook-registered MSM (60.1% Latino, 28% African American; 11.9% other were recruited from online (social networking websites and banner advertisements and offline (local clinics, restaurants and organizations venues frequented by minority MSM. Inclusion criteria required participants to be men who were 18 years of age or older, had had sex with a man in the past 12 months, were living in Los Angeles, and had a Facebook account. Participants completed an online survey on their social media usage and sexual risk behaviors. Results from a multivariable regression suggest that number of sexual partners met from online social networking technologies is associated with increased: 1 likelihood of having exchanged sex for food, drugs, or a place to stay within the past 3 months; 2 number of new partners within the past 3 months; 3 number of male sex partners within the past 3 months; and 4 frequency of engaging in oral sex within the past 3 months, controlling for age, race, education, and total number of sexual partners. Understanding the relationship between social media sex-seeking and sexual risk behaviors among at-risk populations will help inform population-focused HIV prevention and treatment interventions.

  10. "Hard to crack": experiences of community integration among first- and second-generation Asian MSM in Canada.

    Science.gov (United States)

    Nakamura, Nadine; Chan, Elic; Fischer, Benedikt

    2013-07-01

    Asians are the largest racial minority in Canada making up 11% of the population and represented over 60% of new immigrants between 2001 and 2006. We examined the experiences of community integration for first-generation (n = 27) and second-generation (n = 22) Asian Canadian men who have sex with men (MSM) in their ethnic and gay communities. Through focus group interviews, we explored their level of connectedness and the level of discrimination they experienced in the two communities. Findings indicate that Asian MSM in general perceived their ethnic community as homophobic, stemming from a combination of seeing sex as taboo, stereotypes about being gay, and the affiliation with religion. Although the literature indicates that immigrants rely on the support of their ethnic communities, our finding suggest that this is not the case for Asian immigrant MSM, who in our sample reported feeling less connected compared to their second-generation counterparts. For the gay community, our sample reported mixed experiences as some regarded it as welcoming, whereas others described it as racist. However, these experiences did not differ by generational status. Many were aware of explicit messages stating "No Asians" in dating contexts, while at the same time being aware that some older White men were interested in dating Asians exclusively. Barriers to integration in both communities may contribute to feelings of isolation. Theoretical implications are discussed. PsycINFO Database Record (c) 2013 APA, all rights reserved.

  11. The relationship between online social networking and sexual risk behaviors among men who have sex with men (MSM).

    Science.gov (United States)

    Young, Sean D; Szekeres, Greg; Coates, Thomas

    2013-01-01

    Online social networking usage is growing rapidly, especially among at-risk populations, such as men who have sex with men (MSM). However, little research has studied the relationship between online social networking usage and sexual risk behaviors among at-risk populations. One hundred and eighteen Facebook-registered MSM (60.1% Latino, 28% African American; 11.9% other) were recruited from online (social networking websites and banner advertisements) and offline (local clinics, restaurants and organizations) venues frequented by minority MSM. Inclusion criteria required participants to be men who were 18 years of age or older, had had sex with a man in the past 12 months, were living in Los Angeles, and had a Facebook account. Participants completed an online survey on their social media usage and sexual risk behaviors. Results from a multivariable regression suggest that number of sexual partners met from online social networking technologies is associated with increased: 1) likelihood of having exchanged sex for food, drugs, or a place to stay within the past 3 months; 2) number of new partners within the past 3 months; 3) number of male sex partners within the past 3 months; and 4) frequency of engaging in oral sex within the past 3 months, controlling for age, race, education, and total number of sexual partners. Understanding the relationship between social media sex-seeking and sexual risk behaviors among at-risk populations will help inform population-focused HIV prevention and treatment interventions.

  12. Comparative Analysis of Recruitment Strategies in a Study of Men Who Have Sex with Men (MSM) in Metropolitan Detroit.

    Science.gov (United States)

    Iott, Bradley E; Veinot, Tiffany C; Loveluck, Jimena; Kahle, Erin; Golson, Leon; Benton, Akilah

    2018-02-22

    HIV/AIDS-related research requires recruitment of representative samples of MSM; yet, we know little about the comparative yield, diversity and cost-benefit tradeoffs between different recruitment venues. We compared 11 recruitment venues used for nine HIV prevention-related focus groups with MSM in Metropolitan Detroit. Of the 64 participants, 24 were clients recruited via an HIV/AIDS-focused nonprofit, 20 from Grindr advertisements, 6 from university-student email lists, and 5 from flyers/palmcards. Significantly more African-American, low-income and HIV-positive participants were recruited via the nonprofit. The best cost-benefit tradeoffs were for organizational Facebook posts, email groups, personal networking, and nonprofit recruitment. Grindr increased the size of the sample, though at greater expense. Facebook and Scruff advertisements and gay bar outreach represented greater costs than benefits. Only 11.6% of Grindr respondents attended the focus groups. A mix of online and offline recruitment venues can generate a large and diverse sample of MSM, but venue performance is uneven.

  13. Evolutionary history of HIV-1 subtype B and CRF01_AE transmission clusters among men who have sex with men (MSM in Kuala Lumpur, Malaysia.

    Directory of Open Access Journals (Sweden)

    Kim Tien Ng

    Full Text Available HIV-1 epidemics among men who have sex with men (MSM continue to expand in developed and developing countries. Although HIV infection in MSM is amongst the highest of the key affected populations in many countries in Southeast Asia, comprehensive molecular epidemiological study of HIV-1 among MSM remains inadequate in the region including in Malaysia. Here, we reported the phylodynamic profiles of HIV-1 genotypes circulating among MSM population in Kuala Lumpur, Malaysia. A total of n = 459 newly-diagnosed treatment-naïve consenting subjects were recruited between March 2006 and August 2012, of whom 87 (18.9% were self-reported MSM. Transmitted drug resistance mutations were absent in these isolates. Cumulatively, phylogenetic reconstructions of the pro-rt gene (HXB2∶2253-3275 showed that HIV-1 subtype B and CRF01_AE were predominant and contributed to approximately 80% of the total HIV-1 infection among MSM. In addition to numerous unique transmission lineages within these genotypes, twelve monophyletic transmission clusters of different sizes (2-7 MSM sequences, supported by posterior probability value of 1 were identified in Malaysia. Bayesian coalescent analysis estimated that the divergence times for these clusters were mainly dated between 1995 and 2005 with four major transmission clusters radiating at least 12 years ago suggesting that active spread of multiple sub-epidemic clusters occurred during this period. The changes in effective population size of subtype B showed an exponential growth within 5 years between 1988 and 1993, while CRF01_AE lineage exhibited similar expansion between 1993 and 2003. Our study provides the first insight of the phylodynamic profile of HIV-1 subtype B and CRF01_AE circulating among MSM population in Kuala Lumpur, Malaysia, unravelling the importance of understanding transmission behaviours as well as evolutionary history of HIV-1 in assessing the risk of outbreak or epidemic expansion.

  14. Ongoing outbreaks of hepatitis A among men who have sex with men (MSM), Berlin, November 2016 to January 2017 - linked to other German cities and European countries.

    Science.gov (United States)

    Werber, Dirk; Michaelis, Kai; Hausner, Marius; Sissolak, Dagmar; Wenzel, Jürgen; Bitzegeio, Julia; Belting, Anne; Sagebiel, Daniel; Faber, Mirko

    2017-02-02

    Since 14 November 2016, 38 cases of hepatitis A have been notified in Berlin; of these, 37 were male and 30 reported to have sex with men (MSM). Median age of MSM cases is 31 years (range: 24-52 years). Phylogenetic analysis revealed three distinct sequences, linking cases in Berlin to those in other German cities and to clusters recognised in other European countries in 2016. This article is copyright of The Authors, 2017.

  15. The influence of scene context on object recognition is independent of attentional focus

    Directory of Open Access Journals (Sweden)

    Jaap eMunneke

    2013-08-01

    Full Text Available Humans can quickly and accurately recognize objects within briefly presented natural scenes. Previous work has provided evidence that scene context contributes to this process, demonstrating improved naming of objects that were presented in semantically consistent scenes (e.g., a sandcastle on a beach relative to semantically inconsistent scenes (e.g., a sandcastle on a football field. The current study was aimed at investigating which processes underlie the scene consistency effect. Specifically, we tested: 1 whether the effect is due to increased visual feature and/or shape overlap for consistent relative to inconsistent scene-object pairs; and 2 whether the effect is mediated by attention to the background scene. Experiment 1 replicated the scene consistency effect of a previous report (Davenport & Potter, 2004. Using a new, carefully controlled stimulus set, Experiment 2 showed that the scene consistency effect could not be explained by low-level feature or shape overlap between scenes and target objects. Experiments 3a and 3b investigated whether focused attention modulates the scene consistency effect. By using a location cueing manipulation, participants were correctly informed about the location of the target object on a proportion of trials, allowing focused attention to be deployed towards the target object. Importantly, the effect of scene consistency on target object recognition was independent of spatial attention, and was observed both when attention was focused on the target object and when attention was focused on the background scene. These results indicate that a semantically consistent scene context benefits object recognition independently of the focus of attention. We suggest that the scene consistency effect is primarily driven by global scene properties, or scene gist, that can be processed with minimal attentional resources.

  16. Association of Human Papillomavirus Infection and Abnormal Anal Cytology among HIV-Infected MSM in Beijing, China

    Science.gov (United States)

    Zhang, Zhihui; Qian, Han-Zhu; Ruan, Yuhua; Zhou, Feng; Gao, Cong; Li, Mufei; Jin, Qi; Gao, Lei

    2012-01-01

    Background In the recent years, dramatic increases in HIV transmission among men who have sex with men (MSM) have been observed in China. Human papillomavirus (HPV) infection related anal cancer is more common among HIV-infected MSM as compared to the general population. However, HPV infection and anal cytology has been rarely studied in HIV-infected MSM in China. Methods HIV-infected MSM in Beijing, China were invited to participate in this study between January and April 2011. Anal swabs were collected for examining cytology and HPV genotypes. Results Ninety-five eligible participants with complete questionnaire and laboratory data were included in the analyses. Thirty six of them (37.9%) showed abnormal anal cytology as follows: atypical squamous cells of undetermined significance (ASC-US) in 19 (20.0%), atypical squamous cells but cannot exclude HSIL (ASC-H) in 1 (1.1%), low-grade squamous intraepithelial lesion (LSIL) in 15 (15.8%), and high-grade squamous intraepithelial lesion (HSIL) in 1 (1.1%). HPV6 (20.0%), HPV16 (10.9%), HPV56 (10.9%), HPV52 (9.1%) and HPV39 (9.1%) were observed most frequently among those with normal anal cytology, while different distribution was found in the ones with abnormal anal cytology as HPV6 (19.4%), HPV16 (19.4%), HPV45 (16.7%), HPV52 (16.7%) and HPV18 (11.1%). In addition, HPV16, HPV45, HPV52 and HPV18 were the most frequent high-risk types in patients with abnormal anal cytology. HPV multiplicity was found to be significantly related to the prevalence of abnormal anal cytology (p for trend = 0.04). Conclusions High prevalence of HPV infection and abnormal anal cytology was observed among HIV-infected MSM in China. Infection of multiple HPV types or high-risk types was found to be associated with an increased risk of abnormal anal cytology. PMID:22558293

  17. Range sections as rock models for intensity rock scene segmentation

    CSIR Research Space (South Africa)

    Mkwelo, S

    2007-11-01

    Full Text Available can be used to extract intensity edges of relevance in terms of orientation and position. Conventional polynomial fitting is used to extract the underlying rock shape as a final segmentation. Preliminary results on a small laboratory data set using...

  18. Mission Driven Scene Understanding: Candidate Model Training and Validation

    Science.gov (United States)

    2016-09-01

    manufacturer’s or trade names does not constitute an official endorsement or approval of the use thereof. Destroy this report when it is no longer...Theano-AlexNet6,7) installed on a Windows 10 notebook computer. To the best of our knowledge, an implementation of the open-source, Python -based...public release; distribution unlimited. 3 codes benefit from the flexibility and ease in development using the Python language. In contrast, the

  19. Using GIS to reconcile crime scenes with those indicated by serial criminals

    CSIR Research Space (South Africa)

    Cooper, Antony K

    2001-12-01

    Full Text Available includes revisiting the scenes with a GPS receiver to record their coordinates. This quality assurance highlights discrepancies between the crime scenes described in case dockets and those the suspect pointed out, allowing the investigators to link...

  20. Contextual effects of scene on the visual perception of object orientation in depth.

    Directory of Open Access Journals (Sweden)

    Ryosuke Niimi

    Full Text Available We investigated the effect of background scene on the human visual perception of depth orientation (i.e., azimuth angle of three-dimensional common objects. Participants evaluated the depth orientation of objects. The objects were surrounded by scenes with an apparent axis of the global reference frame, such as a sidewalk scene. When a scene axis was slightly misaligned with the gaze line, object orientation perception was biased, as if the gaze line had been assimilated into the scene axis (Experiment 1. When the scene axis was slightly misaligned with the object, evaluated object orientation was biased, as if it had been assimilated into the scene axis (Experiment 2. This assimilation may be due to confusion between the orientation of the scene and object axes (Experiment 3. Thus, the global reference frame may influence object orientation perception when its orientation is similar to that of the gaze-line or object.

  1. Scene-selectivity and retinotopy in medial parietal cortex

    Directory of Open Access Journals (Sweden)

    Edward Harry Silson

    2016-08-01

    Full Text Available Functional imaging studies in human reliably identify a trio of scene-selective regions, one on each of the lateral (occipital place area, OPA, ventral (parahippocampal place area, PPA, and medial (retrosplenial complex, RSC cortical surfaces. Recently, we demonstrated differential retinotopic biases for the contralateral lower and upper visual fields within OPA and PPA, respectively. Here, using fMRI, we combine detailed mapping of both population receptive fields (pRF and category-selectivity, with independently acquired resting-state functional connectivity analyses, to examine scene and retinotopic processing within medial parietal cortex. We identified a medial scene-selective region, which was contained largely within the posterior and ventral bank of the parieto-occipital sulcus (POS. While this region is typically referred to as RSC, the spatial extent of our scene-selective region typically did not extend into retrosplenial cortex, and thus we adopt the term medial place area (MPA to refer to this visually defined scene-selective region. Intriguingly MPA co-localized with a region identified solely on the basis of retinotopic sensitivity using pRF analyses. We found that MPA demonstrates a significant contralateral visual field bias, coupled with large pRF sizes. Unlike OPA and PPA, MPA did not show a consistent bias to a single visual quadrant. MPA also co-localized with a region identified by strong differential functional connectivity with PPA and FFA, commensurate with its functional selectivity. Functional connectivity with OPA was much weaker than with PPA, and similar to that with face-selective OFA, suggesting a closer link with ventral then lateral cortex. Consistent with prior research, we also observed differential functional connectivity in medial parietal cortex for anterior over posterior PPA, as well as a region on the lateral surface, the caudal inferior parietal lobule (cIPL. However, the differential connectivity in

  2. MARCOnI-ConvNet-Based MARker-Less Motion Capture in Outdoor and Indoor Scenes.

    Science.gov (United States)

    Elhayek, A; de Aguiar, E; Jain, A; Thompson, J; Pishchulin, L; Andriluka, M; Bregler, C; Schiele, B; Theobalt, C

    2017-03-01

    Marker-less motion capture has seen great progress, but most state-of-the-art approaches fail to reliably track articulated human body motion with a very low number of cameras, let alone when applied in outdoor scenes with general background. In this paper, we propose a method for accurate marker-less capture of articulated skeleton motion of several subjects in general scenes, indoors and outdoors, even from input filmed with as few as two cameras. The new algorithm combines the strengths of a discriminative image-based joint detection method with a model-based generative motion tracking algorithm through an unified pose optimization energy. The discriminative part-based pose detection method is implemented using Convolutional Networks (ConvNet) and estimates unary potentials for each joint of a kinematic skeleton model. These unary potentials serve as the basis of a probabilistic extraction of pose constraints for tracking by using weighted sampling from a pose posterior that is guided by the model. In the final energy, we combine these constraints with an appearance-based model-to-image similarity term. Poses can be computed very efficiently using iterative local optimization, since joint detection with a trained ConvNet is fast, and since our formulation yields a combined pose estimation energy with analytic derivatives. In combination, this enables to track full articulated joint angles at state-of-the-art accuracy and temporal stability with a very low number of cameras. Our method is efficient and lends itself to implementation on parallel computing hardware, such as GPUs. We test our method extensively and show its advantages over related work on many indoor and outdoor data sets captured by ourselves, as well as data sets made available to the community by other research labs. The availability of good evaluation data sets is paramount for scientific progress, and many existing test data sets focus on controlled indoor settings, do not feature much variety

  3. Surgical scene generation for virtual reality-based training in medicine

    CERN Document Server

    Harders, Matthias

    2008-01-01

    Provides an extensive overview of related work in the three different directions of scene generation and introduces specific solutions in detailIdeal reference for any reader involved in generating training scenarios, as well as in VR-based training in generalDiscusses theoeretically unlimited automatic generation of healthy anatomy within natural variability allowing tedious and time-intensive manual segmentation to be avoidedPresents high-quality synthesis of new textures based on samples and automatic mapping to complex geometries enabling the drawing and mapping of textures to 3D models to

  4. What do We Learn by Semantic Scene Understanding for Remote Sensing imagery in CNN framework?

    OpenAIRE

    Li, Haifeng; Peng, Jian; Tao, Chao; Chen, Jie; Deng, Min

    2017-01-01

    Recently, deep convolutional neural network (DCNN) achieved increasingly remarkable success and rapidly developed in the field of natural image recognition. Compared with the natural image, the scale of remote sensing image is larger and the scene and the object it represents are more macroscopic. This study inquires whether remote sensing scene and natural scene recognitions differ and raises the following questions: What are the key factors in remote sensing scene recognition? Is the DCNN r...

  5. Scene reassembly after multimodal digitization and pipeline evaluation using photorealistic rendering

    DEFF Research Database (Denmark)

    Stets, Jonathan Dyssel; Dal Corso, Alessandro; Nielsen, Jannik Boll

    2017-01-01

    Transparent objects require acquisition modalities that are very different from the ones used for objects with more diffuse reflectance properties. Digitizing a scene where objects must be acquired with different modalities requires scene reassembly after reconstruction of the object surfaces....... This reassembly of a scene that was picked apart for scanning seems unexplored. We contribute with a multimodal digitization pipeline for scenes that require this step of reassembly. Our pipeline includes measurement of bidirectional reflectance distribution functions and high dynamic range imaging...

  6. Ritual Scenes in the Iliad: Rote, Hallowed, or Encrypted as Ancient Art?

    Directory of Open Access Journals (Sweden)

    Margo Kitts

    2011-03-01

    Full Text Available Based in oral poetic and ritual theory, this article proposes that ritual scenes in Homer’s Iliad reflect unique compositional constraints beyond those found in other kinds of typical scenes. The focus is on oath-sacrifices and commensal sacrifices. Both ritual scene types exhibit strong identifying features, although they differ in their formal particulars and cultural implications. It is argued that both sorts of sacrificial scenes preserve especially ancient ritual patterns that may have parallels in Anatolian texts.

  7. Image-based 3D scene analysis for navigation of autonomous airborne systems

    Science.gov (United States)

    Jaeger, Klaus; Bers, Karl-Heinz

    2001-10-01

    In this paper we describe a method for automatic determination of sensor pose (position and orientation) related to a 3D landmark or scene model. The method is based on geometrical matching of 2D image structures with projected elements of the associated 3D model. For structural image analysis and scene interpretation, a blackboard-based production system is used resulting in a symbolic description of image data. Knowledge of the approximated sensor pose measured for example by IMU or GPS enables to estimate an expected model projection used for solving the correspondence problem of image structures and model elements. These correspondences are presupposed for pose computation carried out by nonlinear numerical optimization algorithms. We demonstrate the efficiency of the proposed method by navigation update approaching a bridge scenario and flying over urban area, whereas data were taken with airborne infrared sensors in high oblique view. In doing so we simulated image-based navigation for target engagement and midcourse guidance suited for the concepts of future autonomous systems like missiles and drones.

  8. Detecting Damaged Building Regions Based on Semantic Scene Change from Multi-Temporal High-Resolution Remote Sensing Images

    Directory of Open Access Journals (Sweden)

    Jihui Tu

    2017-04-01

    Full Text Available The detection of damaged building regions is crucial to emergency response actions and rescue work after a disaster. Change detection methods using multi-temporal remote sensing images are widely used for this purpose. Differing from traditional methods based on change detection for damaged building regions, semantic scene change can provide a new point of view since it can indicate the land-use variation at the semantic level. In this paper, a novel method is proposed for detecting damaged building regions based on semantic scene change in a visual Bag-of-Words model. Pre- and post-disaster scene change in building regions are represented by a uniform visual codebook frequency. The scene change of damaged and non-damaged building regions is discriminated using the Support Vector Machine (SVM classifier. An evaluation of experimental results, for a selected study site of the Longtou hill town of Yunnan, China, which was heavily damaged in the Ludian earthquake of 14 March 2013, shows that this method is feasible and effective for detecting damaged building regions. For the experiments, WorldView-2 optical imagery and aerial imagery is used.

  9. Separate and simultaneous adjustment of light qualities in a real scene

    NARCIS (Netherlands)

    Xia, L.; Pont, S.C.; Heynderickx, I.E.J.R.

    2017-01-01

    Humans are able to estimate light field properties in a scene in that they have expectations of the objects' appearance inside it. Previously, we probed such expectations in a real scene by asking whether a "probe object" fitted a real scene with regard to its lighting. But how well are observers

  10. Visual search of traffic scenes : on the effect of location expectations.

    NARCIS (Netherlands)

    Theeuwes, J. & Hagenzieker, M.P.

    1993-01-01

    The present study investigates top-down governed visual selection in natural traffic scenes. The subjects had to search for a target object (for example, a traffic sign, or other road users) which was embedded in a natural traffic scene. Given a particular prototypical scene, the target was located

  11. Scene complexity: influence on perception, memory, and development in the medial temporal lobe

    Directory of Open Access Journals (Sweden)

    Xiaoqian J Chai

    2010-03-01

    Full Text Available Regions in the medial temporal lobe (MTL and prefrontal cortex (PFC are involved in memory formation for scenes in both children and adults. The development in children and adolescents of successful memory encoding for scenes has been associated with increased activation in PFC, but not MTL, regions. However, evidence suggests that a functional subregion of the MTL that supports scene perception, located in the parahippocampal gyrus (PHG, goes through a prolonged maturation process. Here we tested the hypothesis that maturation of scene perception supports the development of memory for complex scenes. Scenes were characterized by their levels of complexity defined by the number of unique object categories depicted in the scene. Recognition memory improved with age, in participants ages 8-24, for high, but not low, complexity scenes. High-complexity compared to low-complexity scenes activated a network of regions including the posterior PHG. The difference in activations for high- versus low- complexity scenes increased with age in the right posterior PHG. Finally, activations in right posterior PHG were associated with age-related increases in successful memory formation for high-, but not low-, complexity scenes. These results suggest that functional maturation of the right posterior PHG plays a critical role in the development of enduring long-term recollection for high-complexity scenes.

  12. Mirth and Murder: Crime Scene Investigation as a Work Context for Examining Humor Applications

    Science.gov (United States)

    Roth, Gene L.; Vivona, Brian

    2010-01-01

    Within work settings, humor is used by workers for a wide variety of purposes. This study examines humor applications of a specific type of worker in a unique work context: crime scene investigation. Crime scene investigators examine death and its details. Members of crime scene units observe death much more frequently than other police officers…

  13. Predictors of bisexual behaviour among MSM attending intervention sites may help in prevention interventions for this bridge to the heterosexual epidemic in India: data from HIV sentinel surveillance.

    Directory of Open Access Journals (Sweden)

    Sheela Godbole

    Full Text Available Indian cultural tradition demanding marriage, many MSM howsoever they self-identify are likely to be married or have sex with women. To consolidate India's HIV prevention gains, it is important to understand and address the interaction between the MSM and heterosexual epidemics in India and create specific interventions for bisexual MSM. The challenge is to identify and intervene this hard to reach population. Data from HIV Sentinel Surveillance 2011 among MSM in four Indian states were analyzed to assess predictors and prevalence of bisexual behaviour in MSM.Between March-May 2011, 4682 men (15-49 years who had anal/oral sex with a male partner in the past month, attending intervention sites and consenting for an un-linked anonymous survey answered an 11- item questionnaire and provided blood for HIV test by finger stick at 19 designated surveillance sites.Of 4682 MSM tested overall, 5% were illiterate, 51% reported only receptive anal intercourse, 21% only penetrative and 28% both. 36% MSM had ever received money for sex. Overall 6.8% were HIV infected. 44% MSM were bisexual in the last six months. On multivariate analysis, 'being bisexual' was found to be independently associated with 'older age': 26-30 years [AOR = 3.1, 95% CI(2.7, 3.7], >30 years [AOR = 6.5, 95% CI(5.5, 7.7]; 'reporting penetrative behaviour alone' with other men [AOR = 5.8, 95% CI(4.8, 7.0, p<0.01] and 'reporting both penetrative and receptive behaviour' [AOR = 2.7, 95% CI(2.3, 3.1 p<0.01]. Those who both paid and received money for sex [AOR = 0.49, 95% CI (0.38, 0.62] were significantly less likely to be bisexual.A substantial proportion of men receiving