Magnetic Shape Memory (MSM) actuators in practical use

International Nuclear Information System (INIS)

Majewska, K; Zak, A; Ostachowicz, W

2009-01-01

Limited practical applications of MSM actuators motivates the authors to start experimental and theoretical research in the field of multifunctional materials. The authors present a concept of using MSM actuators for control, altering and tuning of forced vibrations of a rotor. The main goal of their experimental research is to show how the activation of MSM actuators can influence forced vibration responses of a rotor system in terms of altering and tuning selected rotor resonant frequencies and vibration amplitudes. Experimental results show that MSM actuators can be successfully applied for vibration reduction and vibration control in the case of rotor systems.

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.

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.

Efficient 3D scene modeling and mosaicing

CERN Document Server

Nicosevici, Tudor

2013-01-01

This book proposes a complete pipeline for monocular (single camera) based 3D mapping of terrestrial and underwater environments. The aim is to provide a solution to large-scale scene modeling that is both accurate and efficient. To this end, we have developed a novel Structure from Motion algorithm that increases mapping accuracy by registering camera views directly with the maps. The camera registration uses a dual approach that adapts to the type of environment being mapped.   In order to further increase the accuracy of the resulting maps, a new method is presented, allowing detection of images corresponding to the same scene region (crossovers). Crossovers then used in conjunction with global alignment methods in order to highly reduce estimation errors, especially when mapping large areas. Our method is based on Visual Bag of Words paradigm (BoW), offering a more efficient and simpler solution by eliminating the training stage, generally required by state of the art BoW algorithms.   Also, towards dev...

A hybrid multiview stereo algorithm for modeling urban scenes.

Science.gov (United States)

Lafarge, Florent; Keriven, Renaud; Brédif, Mathieu; Vu, Hoang-Hiep

2013-01-01

We present an original multiview stereo reconstruction algorithm which allows the 3D-modeling of urban scenes as a combination of meshes and geometric primitives. The method provides a compact model while preserving details: Irregular elements such as statues and ornaments are described by meshes, whereas regular structures such as columns and walls are described by primitives (planes, spheres, cylinders, cones, and tori). We adopt a two-step strategy consisting first in segmenting the initial meshbased surface using a multilabel Markov Random Field-based model and second in sampling primitive and mesh components simultaneously on the obtained partition by a Jump-Diffusion process. The quality of a reconstruction is measured by a multi-object energy model which takes into account both photo-consistency and semantic considerations (i.e., geometry and shape layout). The segmentation and sampling steps are embedded into an iterative refinement procedure which provides an increasingly accurate hybrid representation. Experimental results on complex urban structures and large scenes are presented and compared to state-of-the-art multiview stereo meshing algorithms.

Correlates of anal sex roles among Malay and Chinese MSM in Kuala Lumpur, Malaysia.

Science.gov (United States)

Dangerfield, Derek T; Gravitt, Patti; Rompalo, Anne M; Tai, Raymond; Lim, Sin How

2016-03-01

Identifying roles for anal sex is an important issue for populations of MSM. We describe the prevalence of identifying as being 'top', 'bottom', 'versatile', or 'don't know/not applicable' among Malay and Chinese MSM in Kuala Lumpur, Malaysia, and behavioural outcomes according to these labels for sexual role identity. Data analysis was conducted on a survey administered during weekly outreach throughout Kuala Lumpur in 2012. Pearson's Chi square tests were used to compare demographic and behavioural characteristics of MSM who reported roles for anal sex. Binary logistic regression was used to explore the odds of behavioural outcomes among MSM who identified as 'bottom', 'versatile,' and 'don't know' compared to MSM who reported that 'top' was their sexual role. Labels for anal sex roles were significantly associated with condom use for last anal sex. Among MSM who used labels for anal sex roles, MSM who identified as 'bottom' had highest level of not using condoms for last anal sex (24.1%, p = .045). In binary logistic regression model, identifying as 'top' was significantly associated with reporting using a condom during last anal sex and reported consistent condom use for anal sex in the past six months (p = .039 and .017, respectively). With regard to sexual role identity, some MSM may be a part of a special subgroup of at-risk men to be targeted. Future research should evaluate the origins, meanings, and perceptions of these labels, and the developmental process of how these MSM identify with any of these categories. Research should also uncover condom use decision making with regard to these labels for sexual positioning. © The Author(s) 2016.

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.

Long-term nitrite inhalant exposure and cancer risk in MSM

Science.gov (United States)

Dutta, Anupriya; Uno, Hajime; Holman, Alex; Lorenz, David R.; Wolinsky, Steven M.; Gabuzda, Dana

2017-01-01

Objectives: Nitrite inhalants (poppers) are commonly used recreational drugs among MSM and were previously associated with elevated rates of high-risk sexual behavior, HIV and human herpesvirus type 8 (HHV-8) seroconversion, and transient immunosuppressive effects in experimental models. Whether long-term popper use is associated with cancer risk among MSM in the HAART era is unclear. Design: Prospective cohort study of cancer risk in 3223 HIV-infected and uninfected MSM in the Multicenter AIDS Cohort Study from 1996–2010. Methods: Poisson regression models were used to examine the association between heavy popper use (defined as daily or weekly use for at least 1 year) and risk of individual cancers or composite category of virus-associated cancers. Results: Among all participants, heavy popper use was not associated with increased risk of any individual cancers. Among HIV-uninfected men aged 50–70, heavy popper use was associated with increased risk of virus-associated cancer with causes linked to human papillomavirus, HHV-8, and Epstein–Barr virus in models adjusted for demographics, number of sexual partners, immunological parameters (CD4+ cell counts or CD4+/CD8+ ratios), and hepatitis B and C viruses [incidence rate ratio (IRR), 95% confidence interval (CI) 3.24, 1.05–9.96], or sexually transmitted infections (IRR 3.03, 95% CI, 1.01–9.09), as was cumulative use over a 5-year period (IRR 1.012, 95% CI 1.003–1.021; P = 0.007). There was no significant association between heavy popper use and virus-associated cancer in HIV-infected men. Conclusions: Long-term heavy popper use is associated with elevated risk of some virus-associated cancers with causes related to human papillomavirus, HHV-8, and Epstein–Barr virus infections in older HIV-uninfected MSM independent of sexual behavior and immunological parameters. PMID:28441176

Anal squamous intraepithelial lesions in HIV+ MSM

NARCIS (Netherlands)

Siegenbeek van Heukelom, M.L.

2018-01-01

In this thesis we report on several aspects of high-grade anal squamous intraepithelial lesions (HSIL) in HIV+ men who have sex with men (MSM). It is estimated that 10% of HIV+ MSM with anal HSIL will develop anal squamous cell carcinoma (ASCC) over 30 years time. Screening programs similar to

Interactive Procedural Modelling of Coherent Waterfall Scenes

OpenAIRE

Emilien , Arnaud; Poulin , Pierre; Cani , Marie-Paule; Vimont , Ulysse

2015-01-01

International audience; Combining procedural generation and user control is a fundamental challenge for the interactive design of natural scenery. This is particularly true for modelling complex waterfall scenes where, in addition to taking charge of geometric details, an ideal tool should also provide a user with the freedom to shape the running streams and falls, while automatically maintaining physical plausibility in terms of flow network, embedding into the terrain, and visual aspects of...

Research on 3D virtual campus scene modeling based on 3ds Max and VRML

Science.gov (United States)

Kang, Chuanli; Zhou, Yanliu; Liang, Xianyue

2015-12-01

With the rapid development of modem technology, the digital information management and the virtual reality simulation technology has become a research hotspot. Virtual campus 3D model can not only express the real world objects of natural, real and vivid, and can expand the campus of the reality of time and space dimension, the combination of school environment and information. This paper mainly uses 3ds Max technology to create three-dimensional model of building and on campus buildings, special land etc. And then, the dynamic interactive function is realized by programming the object model in 3ds Max by VRML .This research focus on virtual campus scene modeling technology and VRML Scene Design, and the scene design process in a variety of real-time processing technology optimization strategy. This paper guarantees texture map image quality and improve the running speed of image texture mapping. According to the features and architecture of Guilin University of Technology, 3ds Max, AutoCAD and VRML were used to model the different objects of the virtual campus. Finally, the result of virtual campus scene is summarized.

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.

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.

2014-01-01

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. PMID:25381561

People detection in crowded scenes using active contour models

Science.gov (United States)

Sidla, Oliver

2009-01-01

The detection of pedestrians in real-world scenes is a daunting task, especially in crowded situations. Our experience over the last years has shown that active shape models (ASM) can contribute significantly to a robust pedestrian detection system. The paper starts with an overview of shape model approaches, it then explains our approach which builds on top of Eigenshape models which have been trained using real-world data. These models are placed over candidate regions and matched to image gradients using a scoring function which integrates i) point distribution, ii) local gradient orientations iii) local image gradient strengths. A matching and shape model update process is iteratively applied in order to fit the flexible models to the local image content. The weights of the scoring function have a significant impact on the ASM performance. We analyze different settings of scoring weights for gradient magnitude, relative orientation differences, distance between model and gradient in an experiment which uses real-world data. Although for only one pedestrian model in an image computation time is low, the number of necessary processing cycles which is needed to track many people in crowded scenes can become the bottleneck in a real-time application. We describe the measures which have been taken in order to improve the speed of the ASM implementation and make it real-time capable.

Acceptability and Feasibility of a Social-Entrepreneurship Model to Promote HIV Self-testing and linkage to care among MSM

Science.gov (United States)

Zhong, Fei; Tang, Weiming; Cheng, Weibin; Lin, Peng; Wu, Qiongmiao; Cai, Yanshan; Tang, Songyuan; Fan, Lirui; Zhao, Yuteng; Chen, Xi; Mao, Jessica; Meng, Gang; Tucker, Joseph D.; Xu, Huifang

2017-01-01

Background HIV self-testing (HIVST) offers an opportunity to increase HIV testing among people not reached by facility-based services. However, the promotion of HIVST is limited due to insufficient community engagement. We built a Social Entrepreneurship Model (SET) to promote HIVST linkage to care among Chinese MSM in Guangzhou. Method SET model includes a few key steps: Each participant first completed an online survey, and paid a $23 USD (refundable) deposit to get a HIVST kit and a syphilis self-testing (SST) kit. After the testing, the results were sent to the platform by the participants and interpreted by CDC staff. Meanwhile, the deposit was returned to each participant. Finally, the CBO contacted the participants to provide counseling services, confirmation testing and linkage to care. Result During April–June of 2015, a total of 198 MSM completed a preliminary survey and purchased self-testing kits. Among them, the majority were aged under 34 (84.4%) and met partners online (93.1%). In addition, 68.9% of participants ever tested for HIV, and 19.5% had ever performed HIVST. Overall, feedback was received from 192 (97.0%) participants. Among these, 14 people did not use kits, and the HIV and syphilis prevalence among these users were of 4.5% (8/178) and 3.7% (6/178), respectively. All of the screened HIV-positive cases sought further confirmation testing and were linked to care. Conclusion Using an online SET model to promote HIV and syphilis among Chinese MSM is acceptable and feasible, and this model adds a new testing platform to the current testing service system. PMID:27601301

Registration of eye reflection and scene images using an aspherical eye model.

Science.gov (United States)

Nakazawa, Atsushi; Nitschke, Christian; Nishida, Toyoaki

2016-11-01

This paper introduces an image registration algorithm between an eye reflection and a scene image. Although there are currently a large number of image registration algorithms, this task remains difficult due to nonlinear distortions at the eye surface and large amounts of noise, such as iris texture, eyelids, eyelashes, and their shadows. To overcome this issue, we developed an image registration method combining an aspherical eye model that simulates nonlinear distortions considering eye geometry and a two-step iterative registration strategy that obtains dense correspondence of the feature points to achieve accurate image registrations for the entire image region. We obtained a database of eye reflection and scene images featuring four subjects in indoor and outdoor scenes and compared the registration performance with different asphericity conditions. Results showed that the proposed approach can perform accurate registration with an average accuracy of 1.05 deg by using the aspherical cornea model. This work is relevant for eye image analysis in general, enabling novel applications and scenarios.

Disassortative Age-Mixing Does Not Explain Differences in HIV Prevalence between Young White and Black MSM: Findings from Four Studies.

Directory of Open Access Journals (Sweden)

Jeremy Alexander Grey

Full Text Available Age disassortativity is one hypothesis for HIV disparities between Black and White MSM. We examined differences in age mixing by race and the effect of partner age difference on the association between race and HIV status.We used data from four studies of MSM. Participants reported information about recent sexual partners, including age, race, and sexual behavior. Two studies were online with a US sample and two focused on MSM in Atlanta.We computed concordance correlation coefficients (CCCs by race across strata of partner type, participant HIV status, condom use, and number of partners. We used Wilcoxon rank-sum tests to compare Black and White MSM on partner age differences across five age groups. Finally, we used logistic regression models using race, age, and partner age difference to determine the odds ratio of HIV-positive serostatus.Of 48 CCC comparisons, Black MSM were more age-disassortative than White MSM in only two. Furthermore, of 20 comparisons of median partner age, Black and White MSM differed in two age groups. One indicated larger age gaps among the Black MSM (18-19. Prevalent HIV infection was associated with race and age. Including partner age difference in the model resulted in a 2% change in the relative odds of infection among Black MSM.Partner age disassortativity and partner age differences do not differ by race. Partner age difference offers little predictive value in understanding prevalent HIV infection among Black and White MSM, including diagnosis of HIV-positive status among self-reported HIV-negative individuals.

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)

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...

2. Wochenbericht MSM35

OpenAIRE

Schwalenberg, Katrin

2014-01-01

FS Maria S. Merian Reise MSM 35, Warna, Bulgarien - Istanbul, Türkei, 20.01.-07.02.2014 - Untersuchung von Gashydratvorkommen im Donau-Tiefseefächer des Schwarzen Meers mit mariner Elektromagnetik - (27.01.-02.02.2014)

1. Wochenbericht MSM35

OpenAIRE

Schwalenberg, Katrin

2014-01-01

FS Maria S. Merian Reise MSM 35, Warna, Bulgarien - Istanbul, Türkei, 20.01.-07.02.2014 - Untersuchung von Gashydratvorkommen im Donau-Tiefseefächer des Schwarzen Meers mit mariner Elektromagnetik - (20.01.-26.01.2014)

Imaging infrared: Scene simulation, modeling, and real image tracking; Proceedings of the Meeting, Orlando, FL, Mar. 30, 31, 1989

Science.gov (United States)

Triplett, Milton J.; Wolverton, James R.; Hubert, August J.

1989-09-01

Various papers on scene simulation, modeling, and real image tracking using IR imaging are presented. Individual topics addressed include: tactical IR scene generator, dynamic FLIR simulation in flight training research, high-speed dynamic scene simulation in UV to IR spectra, development of an IR sensor calibration facility, IR celestial background scene description, transmission measurement of optical components at cryogenic temperatures, diffraction model for a point-source generator, silhouette-based tracking for tactical IR systems, use of knowledge in electrooptical trackers, detection and classification of target formations in IR image sequences, SMPRAD: simplified three-dimensional cloud radiance model, IR target generator, recent advances in testing of thermal imagers, generic IR system models with dynamic image generation, modeling realistic target acquisition using IR sensors in multiple-observer scenarios, and novel concept of scene generation and comprehensive dynamic sensor test.

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.

Terrain Simplification Research in Augmented Scene Modeling

Institute of Scientific and Technical Information of China (English)

无

2001-01-01

environment. As one of the most important tasks in augmented scene modeling, terrain simplification research has gained more and more attention. In this paper, we mainly focus on point selection problem in terrain simplification using triangulated irregular network. Based on the analysis and comparison of traditional importance measures for each input point, we put forward a new importance measure based on local entropy. The results demonstrate that the local entropy criterion has a better performance than any traditional methods. In addition, it can effectively conquer the "short-sight" problem associated with the traditional methods.

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

Scene-Based Contextual Cueing in Pigeons

Science.gov (United States)

Wasserman, Edward A.; Teng, Yuejia; Brooks, Daniel I.

2014-01-01

Repeated pairings of a particular visual context with a specific location of a target stimulus facilitate target search in humans. We explored an animal model of such contextual cueing. Pigeons had to peck a target which could appear in one of four locations on color photographs of real-world scenes. On half of the trials, each of four scenes was consistently paired with one of four possible target locations; on the other half of the trials, each of four different scenes was randomly paired with the same four possible target locations. In Experiments 1 and 2, pigeons exhibited robust contextual cueing when the context preceded the target by 1 s to 8 s, with reaction times to the target being shorter on predictive-scene trials than on random-scene trials. Pigeons also responded more frequently during the delay on predictive-scene trials than on random-scene trials; indeed, during the delay on predictive-scene trials, pigeons predominately pecked toward the location of the upcoming target, suggesting that attentional guidance contributes to contextual cueing. In Experiment 3, involving left-right and top-bottom scene reversals, pigeons exhibited stronger control by global than by local scene cues. These results attest to the robustness and associative basis of contextual cueing in pigeons. PMID:25546098

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

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; Hav Lyon Study Group; Cotte, Laurent

2017-11-01

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.

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.

Sex in public and private settings among Latino MSM

Science.gov (United States)

Reisen, Carol A; Iracheta, Miguel A.; Zea, Maria Cecilia; Bianchi, Fernanda T.; Poppen, Paul J.

2009-01-01

Latino men who have sex with men (MSM) constitute a group at high risk for HIV. Recent approaches to understanding sexual risk have emphasized the role that contextual factors can play in shaping behavior. This study examined sexual behavior of Latino MSM in private and public settings. First, a within-person comparison of behaviors performed in sexual encounters that occurred in public and private settings was conducted. Unprotected anal intercourse and other sexual behaviors involving anal stimulation were more common in private settings; group sex was more likely in public settings. Second, a between-person analysis compared sexual behaviors of MSM who went to three different types of public sex settings during the previous six months. The types were: 1) commercial sex venues (CSVs), which were defined as businesses with the function of providing a space where MSM can go to have sexual encounters, such as gay bathhouses; 2) commercial sex environments (CSEs), which were defined as businesses with another apparent function, but in which MSM sometimes have sexual encounters, such as gay bars or pornographic movie houses; and 3) public sex environments (PSEs), which were defined as free public areas where MSM can go to find partners for anonymous sex, such as parks or public restrooms. Results indicated that anal sexual behavior was most likely to occur in CSVs and least likely in PSEs, but the probability of unprotected anal intercourse was not found to differ among the three types of settings. Behavioral differences were discussed in terms of structural conditions related to privacy and safety, and psychological factors related to intimacy. PMID:20461575

Phylodynamics of HIV-1 subtype B among the men-having-sex-with-men (MSM population in Hong Kong.

Directory of Open Access Journals (Sweden)

Jonathan Hon-Kwan Chen

Full Text Available The men-having-sex-with-men (MSM population has become one of the major risk groups for HIV-1 infection in the Asia Pacific countries. Hong Kong is located in the centre of Asia and the transmission history of HIV-1 subtype B transmission among MSM remained unclear. The aim of this study was to investigate the transmission dynamics of HIV-1 subtype B virus in the Hong Kong MSM population. Samples of 125 HIV-1 subtype B infected MSM patients were recruited in this study. Through this study, the subtype B epidemic in the Hong Kong MSM population was identified spreading mainly among local Chinese who caught infection locally. On the other hand, HIV-1 subtype B infected Caucasian MSM caught infection mainly outside Hong Kong. The Bayesian phylogenetic analysis also indicated that 3 separate subtype B epidemics with divergence dates in the 1990s had occurred. The first and latest epidemics were comparatively small-scaled; spreading among the local Chinese MSM while sauna-visiting was found to be the major sex partner sourcing reservoir for the first subtype B epidemic. However, the second epidemic was spread in a large-scale among local Chinese MSM with a number of them having sourced their sex partners through the internet. The epidemic virus was estimated to have a divergence date in 1987 and the infected population in Hong Kong had a logistic growth throughout the past 20 years. Our study elucidated the evolutionary and demographic history of HIV-1 subtype B virus in Hong Kong MSM population. The understanding of transmission and growth model of the subtype B epidemic provides more information on the HIV-1 transmission among MSM population in other Asia Pacific high-income countries.

HIV intertest interval among MSM in King County, Washington.

Science.gov (United States)

Katz, David A; Dombrowski, Julia C; Swanson, Fred; Buskin, Susan E; Golden, Matthew R; Stekler, Joanne D

2013-02-01

The authors examined temporal trends and correlates of HIV testing frequency among men who have sex with men (MSM) in King County, Washington. The authors evaluated data from MSM testing for HIV at the Public Health-Seattle & King County (PHSKC) STD Clinic and Gay City Health Project (GCHP) and testing history data from MSM in PHSKC HIV surveillance. The intertest interval (ITI) was defined as the number of days between the last negative HIV test and the current testing visit or first positive test. Correlates of the log(10)-transformed ITI were determined using generalised estimating equations linear regression. Between 2003 and 2010, the median ITI among MSM seeking HIV testing at the STD Clinic and GCHP were 215 (IQR: 124-409) and 257 (IQR: 148-503) days, respectively. In multivariate analyses, younger age, having only male partners and reporting ≥10 male sex partners in the last year were associated with shorter ITIs at both testing sites (pGCHP attendees, having a regular healthcare provider, seeking a test as part of a regular schedule and inhaled nitrite use in the last year were also associated with shorter ITIs (pGCHP (median 359 vs 255 days, p=0.02). Although MSM in King County appear to be testing at frequent intervals, further efforts are needed to reduce the time that HIV-infected persons are unaware of their status.

Superpixel-Based Feature for Aerial Image Scene Recognition

Directory of Open Access Journals (Sweden)

Hongguang Li

2018-01-01

Full Text Available Image scene recognition is a core technology for many aerial remote sensing applications. Different landforms are inputted as different scenes in aerial imaging, and all landform information is regarded as valuable for aerial image scene recognition. However, the conventional features of the Bag-of-Words model are designed using local points or other related information and thus are unable to fully describe landform areas. This limitation cannot be ignored when the aim is to ensure accurate aerial scene recognition. A novel superpixel-based feature is proposed in this study to characterize aerial image scenes. Then, based on the proposed feature, a scene recognition method of the Bag-of-Words model for aerial imaging is designed. The proposed superpixel-based feature that utilizes landform information establishes top-task superpixel extraction of landforms to bottom-task expression of feature vectors. This characterization technique comprises the following steps: simple linear iterative clustering based superpixel segmentation, adaptive filter bank construction, Lie group-based feature quantification, and visual saliency model-based feature weighting. Experiments of image scene recognition are carried out using real image data captured by an unmanned aerial vehicle (UAV. The recognition accuracy of the proposed superpixel-based feature is 95.1%, which is higher than those of scene recognition algorithms based on other local features.

Ethnicity moderates the relationship between perceived stress and benefit finding in HIV+ men who have sex with men (MSM).

Science.gov (United States)

Seay, Julia S; Fekete, Erin M; Antoni, Michael H; Ironson, Gail; Fletcher, MaryAnn; Schneiderman, Neil

2014-04-01

Numerous studies conducted within the USA demonstrate higher levels of benefit finding in ethnic minority individuals compared to nonminority individuals living with chronic disease. As benefit finding may be a salient buffer for the effects of stress, the current study examined the association between perceived stress and benefit finding in human immunodeficiency virus (HIV)+ men who have sex with men (MSM) living in the southeast USA and investigated whether ethnicity was a moderator of this relationship. We hypothesized that benefit finding would be greater in ethnic minority MSM than in white MSM and that ethnic minority MSM with high levels of stress would experience greater benefit finding than their white MSM counterparts. The current study utilized baseline (T1) and 3-month follow-up (T2) data drawn from a previous trial of a psychosocial intervention in HIV+ MSM. Participants were 130 HIV+ MSM; 52 % were white and 48 % belonged to minority ethnic groups (African-American, Caribbean-American, Hispanic). Analyses revealed that benefit finding was greater in ethnic minority MSM at baseline; however, this difference became nonsignificant when age, education level, highly active antiretroviral therapy adherence, and CD4 count were added to the model. Moderated regression analyses revealed a significant interaction between T1 perceived stress and ethnicity in predicting T2 benefit finding, such that higher levels of T1 perceived stress predicted lower levels of T2 benefit finding in ethnic minority MSM only. This association was independent of intervention group assignment. The current study's results highlight potential differences in the relationship between stress and benefit finding processes in white and ethnic minority HIV+ MSM.

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.

3D Traffic Scene Understanding From Movable Platforms.

Science.gov (United States)

Geiger, Andreas; Lauer, Martin; Wojek, Christian; Stiller, Christoph; Urtasun, Raquel

2014-05-01

In this paper, we present a novel probabilistic generative model for multi-object traffic scene understanding from movable platforms which reasons jointly about the 3D scene layout as well as the location and orientation of objects in the scene. In particular, the scene topology, geometry, and traffic activities are inferred from short video sequences. Inspired by the impressive driving capabilities of humans, our model does not rely on GPS, lidar, or map knowledge. Instead, it takes advantage of a diverse set of visual cues in the form of vehicle tracklets, vanishing points, semantic scene labels, scene flow, and occupancy grids. For each of these cues, we propose likelihood functions that are integrated into a probabilistic generative model. We learn all model parameters from training data using contrastive divergence. Experiments conducted on videos of 113 representative intersections show that our approach successfully infers the correct layout in a variety of very challenging scenarios. To evaluate the importance of each feature cue, experiments using different feature combinations are conducted. Furthermore, we show how by employing context derived from the proposed method we are able to improve over the state-of-the-art in terms of object detection and object orientation estimation in challenging and cluttered urban environments.

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.

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)

Visual search in scenes involves selective and non-selective pathways

Science.gov (United States)

Wolfe, Jeremy M; Vo, Melissa L-H; Evans, Karla K; Greene, Michelle R

2010-01-01

How do we find objects in scenes? For decades, visual search models have been built on experiments in which observers search for targets, presented among distractor items, isolated and randomly arranged on blank backgrounds. Are these models relevant to search in continuous scenes? This paper argues that the mechanisms that govern artificial, laboratory search tasks do play a role in visual search in scenes. However, scene-based information is used to guide search in ways that had no place in earlier models. Search in scenes may be best explained by a dual-path model: A “selective” path in which candidate objects must be individually selected for recognition and a “non-selective” path in which information can be extracted from global / statistical information. PMID:21227734

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.

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.

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.

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.

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.

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.

Correlates of sexual violence among Men who have sex with Men (MSM) in Tijuana, Mexico

Science.gov (United States)

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

2016-01-01

Sexual violence against men who have sex with men (MSM) is prevalent in developing countries and is associated with increased HIV/STI risk. Despite high HIV prevalence (20%) among MSM in Tijuana, Mexico, little attention has been paid to the occurrence of sexual violence in this high-risk group. The present study used a syndemic conditions framework to examine correlates of sexual violence victimization in a sample of 201 MSM surveyed in Tijuana, Mexico during 2012 and 2013. Participants were recruited through respondent-driven sampling (RDS) and underwent a two-hour baseline interview and testing for HIV and syphilis. Sexual violence was defined as any incident during the past year in which the participant had been raped, sexually molested, or sexually harassed. The majority of participants self-identified as gay or bisexual, had never married, were employed, and had a high school education or greater. The average age was 29.7 years. Thirty-nine percent reported sexual violence in the past year. A hierarchical multiple linear regression model predicting more experiences of sexual violence was tested. In a final model, a higher number of experiences of sexual violence was associated with a history of childhood sexual abuse, more adult experiences of homophobia, more depression and hostility symptoms, and not living with a spouse or steady partner. The findings from this study support a model of co-occurring psychosocial factors that increase the likelihood of sexual violence experiences among MSM. Multi-level approaches to the prevention of childhood and adult experiences of sexual violence and homophobia are needed to avert the development of adverse mental and physical health outcomes associated with sexual violence victimization. PMID:27178173

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

A Multi-Wavelength Thermal Infrared and Reflectance Scene Simulation Model

Science.gov (United States)

Ballard, J. R., Jr.; Smith, J. A.; Smith, David E. (Technical Monitor)

2002-01-01

Several theoretical calculations are presented and our approach discussed for simulating overall composite scene thermal infrared exitance and canopy bidirectional reflectance of a forest canopy. Calculations are performed for selected wavelength bands of the DOE Multispectral Thermal Imagery and comparisons with atmospherically corrected MTI imagery are underway. NASA EO-1 Hyperion observations also are available and the favorable comparison of our reflective model results with these data are reported elsewhere.

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.

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.

Marketing the HIV test to MSM: ethnic differences in preferred venues and sources.

Science.gov (United States)

Lechuga, Julia; Owczarzak, Jill T; Petroll, Andrew E

2013-05-01

Lack of awareness of HIV status is associated with an increased likelihood of HIV transmission. We surveyed 633 men who have sex with men (MSM) from diverse ethnic groups recruited from a variety of community venues in a U.S. Midwestern city with rising HIV infection rates. Our first aim was to describe patterns of sexual risk, annual HIV testing frequency, and venues where information about HIV and HIV testing could be disseminated to inner-city MSM. Our second aim was to identify preferred sources to receive information about HIV testing and determine whether these preferences differed by ethnic background. Results indicated that despite similar proportions of high-sexual risk behaviors, compared with African American and Latino MSM, smaller proportions of non-Hispanic White MSM had received an HIV test in the last 12 months. Despite ethnic differences in health care access, a physician's office was the most common HIV testing site. Overall, a majority conveyed a preference to see advertisements in mainstream media outlets. However, when preferences were stratified by ethnicity, African American MSM were the least likely to prefer receiving information from mainstream media and conveyed a stronger preference to receive information from authority figures than non-Hispanic White and Hispanic MSM.

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.

HIV Among MSM and Heterosexual Women in the United States: An Ecologic Analysis.

Science.gov (United States)

Raymond, H Fisher; Al-Tayyib, Alia; Neaigus, Alan; Reilly, Kathleen H; Braunstein, Sarah; Brady, Kathleen A; Sey, Ekow; Risser, Jan; Padget, Paige; Lalota, Marlene; Schacht, John-Mark; Forrest, David W; Macomber, Katie; Griffin, Vivian; Higgins, Emily; Robinson, William T; Zarwell, Meagan C; Opoku, Jenevieve; Magnus, Manya; Kuo, Irene; Burt, Richard; Thiede, Hanne; Glick, Sara; Flynn, Colin; German, Danielle

2017-07-01

Phylogenetic studies show links between heterosexual women and men who have sex with men (MSM) that are more numerous than from heterosexual men to women suggesting that HIV infections among heterosexual women may stem from MSM. Poor communities have been associated with high rates of HIV among heterosexual women. Our analysis investigates potential transmission of HIV between MSM and female heterosexuals. National HIV Behavioral Surveillance data describe transmission risk behaviors of MSM, and HIV case reporting data describe the percentages of cases that are attributed to transmission risk categories. We examined correlations between the percentages of men who were MSM who also have sex with women and female heterosexual cases. We also examined census data to characterize each city in terms of poverty level and race/ethnicity makeup. There was a high correlation (0.93) between the percentage of reported living HIV cases attributed to male heterosexual contact and female heterosexual contact and a moderate nonsignificant correlation (0.49) between the percentage of MSM who were men who have sex with men and women (MSMW) in National HIV Behavioral Surveillance and the percentage of reported cases that were attributed to female heterosexual contact suggesting some potential overlap. Cities with high levels of poverty and African American/Black residents had higher levels of MSMW and higher levels of heterosexual female cases. Addressing HIV in cities with high levels of MSMW may have the dual effect of improving the health of MSM populations that have a high burden of HIV and to improve the health of their larger communities.

Scene incongruity and attention.

Science.gov (United States)

Mack, Arien; Clarke, Jason; Erol, Muge; Bert, John

2017-02-01

Does scene incongruity, (a mismatch between scene gist and a semantically incongruent object), capture attention and lead to conscious perception? We explored this question using 4 different procedures: Inattention (Experiment 1), Scene description (Experiment 2), Change detection (Experiment 3), and Iconic Memory (Experiment 4). We found no differences between scene incongruity and scene congruity in Experiments 1, 2, and 4, although in Experiment 3 change detection was faster for scenes containing an incongruent object. We offer an explanation for why the change detection results differ from the results of the other three experiments. In all four experiments, participants invariably failed to report the incongruity and routinely mis-described it by normalizing the incongruent object. None of the results supports the claim that semantic incongruity within a scene invariably captures attention and provide strong evidence of the dominant role of scene gist in determining what is perceived. Copyright © 2016 Elsevier Inc. All rights reserved.

Disclosure appraisal mediating the association between perceived stigma and HIV disclosure to casual sex partners among HIV+ MSM: a path model analysis.

Science.gov (United States)

Li, Haochu; Chen, Xinguang; Yu, Bin

2016-01-01

HIV stigma is widely believed to be related to HIV disclosure. However, there is a dearth of studies examining the mechanisms that link stigma to disclosure. This is a specific study to assess the relationship between perceived stigma and HIV disclosure to casual sex partners based on a social cognitive theory. HIV+ men who have sex with men (MSM) from two US cities (N = 297) completed questionnaires administered using audio computer-assisted self-interviewing. Path modeling analysis was used to assess the theory-based structural relationships. Perceived stigma was negatively associated with attitudes, intention and behavior of HIV disclosure to casual sex partners. The association was fully mediated by disclosure appraisal, including disclosure outcome expectations, costs and self-efficacy. Findings of this study add new knowledge regarding HIV stigma and disclosure, and provide timely data supporting more effective behavioral interventions to encourage HIV disclosure among MSM.

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.

PC Scene Generation

Science.gov (United States)

Buford, James A., Jr.; Cosby, David; Bunfield, Dennis H.; Mayhall, Anthony J.; Trimble, Darian E.

2007-04-01

AMRDEC has successfully tested hardware and software for Real-Time Scene Generation for IR and SAL Sensors on COTS PC based hardware and video cards. AMRDEC personnel worked with nVidia and Concurrent Computer Corporation to develop a Scene Generation system capable of frame rates of at least 120Hz while frame locked to an external source (such as a missile seeker) with no dropped frames. Latency measurements and image validation were performed using COTS and in-house developed hardware and software. Software for the Scene Generation system was developed using OpenSceneGraph.

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

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

count 350/μl. We investigated what would be required to reduce HIV incidence in MSM to below 1 per 1000 person-years (i.e. cost-effective. METHODS: A dynamic, individual-based simulation model was calibrated to multiple data sources...... with viral suppression to 80%, and it would be 90%, if ART is initiated at diagnosis. The scenarios required for such a policy to be cost-effective are presented. CONCLUSION: This analysis provides targets for the proportion of all HIV-positive MSM with viral suppression required to achieve substantial......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...

Statistics of high-level scene context.

Science.gov (United States)

Greene, Michelle R

2013-01-01

CONTEXT IS CRITICAL FOR RECOGNIZING ENVIRONMENTS AND FOR SEARCHING FOR OBJECTS WITHIN THEM: contextual associations have been shown to modulate reaction time and object recognition accuracy, as well as influence the distribution of eye movements and patterns of brain activations. However, we have not yet systematically quantified the relationships between objects and their scene environments. Here I seek to fill this gap by providing descriptive statistics of object-scene relationships. A total of 48, 167 objects were hand-labeled in 3499 scenes using the LabelMe tool (Russell et al., 2008). From these data, I computed a variety of descriptive statistics at three different levels of analysis: the ensemble statistics that describe the density and spatial distribution of unnamed "things" in the scene; the bag of words level where scenes are described by the list of objects contained within them; and the structural level where the spatial distribution and relationships between the objects are measured. The utility of each level of description for scene categorization was assessed through the use of linear classifiers, and the plausibility of each level for modeling human scene categorization is discussed. Of the three levels, ensemble statistics were found to be the most informative (per feature), and also best explained human patterns of categorization errors. Although a bag of words classifier had similar performance to human observers, it had a markedly different pattern of errors. However, certain objects are more useful than others, and ceiling classification performance could be achieved using only the 64 most informative objects. As object location tends not to vary as a function of category, structural information provided little additional information. Additionally, these data provide valuable information on natural scene redundancy that can be exploited for machine vision, and can help the visual cognition community to design experiments guided by statistics

[Study on the modeling of earth-atmosphere coupling over rugged scenes for hyperspectral remote sensing].

Science.gov (United States)

Zhao, Hui-Jie; Jiang, Cheng; Jia, Guo-Rui

2014-01-01

Adjacency effects may introduce errors in the quantitative applications of hyperspectral remote sensing, of which the significant item is the earth-atmosphere coupling radiance. However, the surrounding relief and shadow induce strong changes in hyperspectral images acquired from rugged terrain, which is not accurate to describe the spectral characteristics. Furthermore, the radiative coupling process between the earth and the atmosphere is more complex over the rugged scenes. In order to meet the requirements of real-time processing in data simulation, an equivalent reflectance of background was developed by taking into account the topography and the geometry between surroundings and targets based on the radiative transfer process. The contributions of the coupling to the signal at sensor level were then evaluated. This approach was integrated to the sensor-level radiance simulation model and then validated through simulating a set of actual radiance data. The results show that the visual effect of simulated images is consistent with that of observed images. It was also shown that the spectral similarity is improved over rugged scenes. In addition, the model precision is maintained at the same level over flat scenes.

Structural barriers to HIV prevention among men who have sex with men (MSM) in Vietnam: Diversity, stigma, and healthcare access.

Science.gov (United States)

Philbin, Morgan M; Hirsch, Jennifer S; Wilson, Patrick A; Ly, An Thanh; Giang, Le Minh; Parker, Richard G

2018-01-01

Men who have sex with men (MSM) in Vietnam experience disproportionate rates of HIV infection. To advance understanding of how structural barriers may shape their engagement with HIV prevention services, we draw on 32 in-depth interviews and four focus groups (n = 31) conducted with MSM in Hanoi between October 2015- March 2016. Three primary factors emerged: (1) Diversity, both in relation to identity and income; Vietnamese MSM described themselves as segregated into Bóng kín (hidden, often heterosexually-identified MSM) and Bóng lộ ('out,' transgender, or effeminate MSM). Lower-income, 'hidden' MSM from rural areas were reluctant to access MSM-targeted services; (2) Stigma: MSM reported being stigmatized by the healthcare system, family, and other MSM; and (3) Healthcare access: this was limited due to economic barriers and lack of MSM-friendly services. Our research suggests the need for multiple strategies to reach diverse types of MSM as well as to address barriers in access to health services such as stigma and costs. While a great deal has been written about the diversity of MSM in relation to gender performance and sexual identities, our research points to the substantial structural-level barriers that must be addressed in order to achieve meaningful and effective HIV prevention for MSM worldwide.

Overt attention in natural scenes: objects dominate features.

Science.gov (United States)

Stoll, Josef; Thrun, Michael; Nuthmann, Antje; Einhäuser, Wolfgang

2015-02-01

Whether overt attention in natural scenes is guided by object content or by low-level stimulus features has become a matter of intense debate. Experimental evidence seemed to indicate that once object locations in a scene are known, salience models provide little extra explanatory power. This approach has recently been criticized for using inadequate models of early salience; and indeed, state-of-the-art salience models outperform trivial object-based models that assume a uniform distribution of fixations on objects. Here we propose to use object-based models that take a preferred viewing location (PVL) close to the centre of objects into account. In experiment 1, we demonstrate that, when including this comparably subtle modification, object-based models again are at par with state-of-the-art salience models in predicting fixations in natural scenes. One possible interpretation of these results is that objects rather than early salience dominate attentional guidance. In this view, early-salience models predict fixations through the correlation of their features with object locations. To test this hypothesis directly, in two additional experiments we reduced low-level salience in image areas of high object content. For these modified stimuli, the object-based model predicted fixations significantly better than early salience. This finding held in an object-naming task (experiment 2) and a free-viewing task (experiment 3). These results provide further evidence for object-based fixation selection--and by inference object-based attentional guidance--in natural scenes. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

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

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.

Hierarchy-associated semantic-rule inference framework for classifying indoor scenes

Science.gov (United States)

Yu, Dan; Liu, Peng; Ye, Zhipeng; Tang, Xianglong; Zhao, Wei

2016-03-01

Typically, the initial task of classifying indoor scenes is challenging, because the spatial layout and decoration of a scene can vary considerably. Recent efforts at classifying object relationships commonly depend on the results of scene annotation and predefined rules, making classification inflexible. Furthermore, annotation results are easily affected by external factors. Inspired by human cognition, a scene-classification framework was proposed using the empirically based annotation (EBA) and a match-over rule-based (MRB) inference system. The semantic hierarchy of images is exploited by EBA to construct rules empirically for MRB classification. The problem of scene classification is divided into low-level annotation and high-level inference from a macro perspective. Low-level annotation involves detecting the semantic hierarchy and annotating the scene with a deformable-parts model and a bag-of-visual-words model. In high-level inference, hierarchical rules are extracted to train the decision tree for classification. The categories of testing samples are generated from the parts to the whole. Compared with traditional classification strategies, the proposed semantic hierarchy and corresponding rules reduce the effect of a variable background and improve the classification performance. The proposed framework was evaluated on a popular indoor scene dataset, and the experimental results demonstrate its effectiveness.

Crystal Structure and Biochemical Characterization of a Mycobacterium smegmatis AAA-Type Nucleoside Triphosphatase Phosphohydrolase (Msm0858).

Science.gov (United States)

Unciuleac, Mihaela-Carmen; Smith, Paul C; Shuman, Stewart

2016-05-15

AAA proteins (ATPases associated with various cellular activities) use the energy of ATP hydrolysis to drive conformational changes in diverse macromolecular targets. Here, we report the biochemical characterization and 2.5-Å crystal structure of a Mycobacterium smegmatis AAA protein Msm0858, the ortholog of Mycobacterium tuberculosis Rv0435c. Msm0858 is a magnesium-dependent ATPase and is active with all nucleoside triphosphates (NTPs) and deoxynucleoside triphosphates (dNTPs) as substrates. The Msm0858 structure comprises (i) an N-terminal domain (amino acids [aa] 17 to 201) composed of two β-barrel modules and (ii) two AAA domains, D1 (aa 212 to 473) and D2 (aa 476 to 744), each of which has ADP in the active site. Msm0858-ADP is a monomer in solution and in crystallized form. Msm0858 domains are structurally homologous to the corresponding modules of mammalian p97. However, the position of the N-domain modules relative to the AAA domains in the Msm0858-ADP tertiary structure is different and would impede the formation of a p97-like hexameric quaternary structure. Mutational analysis of the A-box and B-box motifs indicated that the D1 and D2 AAA domains are both capable of ATP hydrolysis. Simultaneous mutations of the D1 and D2 active-site motifs were required to abolish ATPase activity. ATPase activity was effaced by mutation of the putative D2 arginine finger, suggesting that Msm0858 might oligomerize during the ATPase reaction cycle. A truncated variant Msm0858 (aa 212 to 745) that lacks the N domain was characterized as a catalytically active homodimer. Recent studies have underscored the importance of AAA proteins (ATPases associated with various cellular activities) in the physiology of mycobacteria. This study reports the ATPase activity and crystal structure of a previously uncharacterized mycobacterial AAA protein, Msm0858. Msm0858 consists of an N-terminal β-barrel domain and two AAA domains, each with ADP bound in the active site. Msm0858 is a

Explicit Foreground and Background Modeling in The Classification of Text Blocks in Scene Images

NARCIS (Netherlands)

Sriman, Bowornrat; Schomaker, Lambertus

2015-01-01

Achieving high accuracy for classifying foreground and background is an interesting challenge in the field of scene image analysis because of the wide range of illumination, complex background, and scale changes. Classifying fore- ground and background using bag-of-feature model gives a good result.

The primal scene and symbol formation.

Science.gov (United States)

Niedecken, Dietmut

2016-06-01

This article discusses the meaning of the primal scene for symbol formation by exploring its way of processing in a child's play. The author questions the notion that a sadomasochistic way of processing is the only possible one. A model of an alternative mode of processing is being presented. It is suggested that both ways of processing intertwine in the "fabric of life" (D. Laub). Two clinical vignettes, one from an analytic child psychotherapy and the other from the analysis of a 30 year-old female patient, illustrate how the primal scene is being played out in the form of a terzet. The author explores whether the sadomasochistic way of processing actually precedes the "primal scene as a terzet". She discusses if it could even be regarded as a precondition for the formation of the latter or, alternatively, if the "combined parent-figure" gives rise to ways of processing. The question is being left open. Finally, it is shown how both modes of experiencing the primal scene underlie the discoursive and presentative symbol formation, respectively. Copyright © 2015 Institute of Psychoanalysis.

Advanced radiometric and interferometric milimeter-wave scene simulations

Science.gov (United States)

Hauss, B. I.; Moffa, P. J.; Steele, W. G.; Agravante, H.; Davidheiser, R.; Samec, T.; Young, S. K.

1993-01-01

Smart munitions and weapons utilize various imaging sensors (including passive IR, active and passive millimeter-wave, and visible wavebands) to detect/identify targets at short standoff ranges and in varied terrain backgrounds. In order to design and evaluate these sensors under a variety of conditions, a high-fidelity scene simulation capability is necessary. Such a capability for passive millimeter-wave scene simulation exists at TRW. TRW's Advanced Radiometric Millimeter-Wave Scene Simulation (ARMSS) code is a rigorous, benchmarked, end-to-end passive millimeter-wave scene simulation code for interpreting millimeter-wave data, establishing scene signatures and evaluating sensor performance. In passive millimeter-wave imaging, resolution is limited due to wavelength and aperture size. Where high resolution is required, the utility of passive millimeter-wave imaging is confined to short ranges. Recent developments in interferometry have made possible high resolution applications on military platforms. Interferometry or synthetic aperture radiometry allows the creation of a high resolution image with a sparsely filled aperture. Borrowing from research work in radio astronomy, we have developed and tested at TRW scene reconstruction algorithms that allow the recovery of the scene from a relatively small number of spatial frequency components. In this paper, the TRW modeling capability is described and numerical results are presented.

Dynamics of scene representations in the human brain revealed by magnetoencephalography and deep neural networks

Science.gov (United States)

Cichy, Radoslaw Martin; Khosla, Aditya; Pantazis, Dimitrios; Oliva, Aude

2017-01-01

Human scene recognition is a rapid multistep process evolving over time from single scene image to spatial layout processing. We used multivariate pattern analyses on magnetoencephalography (MEG) data to unravel the time course of this cortical process. Following an early signal for lower-level visual analysis of single scenes at ~100 ms, we found a marker of real-world scene size, i.e. spatial layout processing, at ~250 ms indexing neural representations robust to changes in unrelated scene properties and viewing conditions. For a quantitative model of how scene size representations may arise in the brain, we compared MEG data to a deep neural network model trained on scene classification. Representations of scene size emerged intrinsically in the model, and resolved emerging neural scene size representation. Together our data provide a first description of an electrophysiological signal for layout processing in humans, and suggest that deep neural networks are a promising framework to investigate how spatial layout representations emerge in the human brain. PMID:27039703

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.

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.

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.

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.

Scene Integration Without Awareness: No Conclusive Evidence for Processing Scene Congruency During Continuous Flash Suppression.

Science.gov (United States)

Moors, Pieter; Boelens, David; van Overwalle, Jaana; Wagemans, Johan

2016-07-01

A recent study showed that scenes with an object-background relationship that is semantically incongruent break interocular suppression faster than scenes with a semantically congruent relationship. These results implied that semantic relations between the objects and the background of a scene could be extracted in the absence of visual awareness of the stimulus. In the current study, we assessed the replicability of this finding and tried to rule out an alternative explanation dependent on low-level differences between the stimuli. Furthermore, we used a Bayesian analysis to quantify the evidence in favor of the presence or absence of a scene-congruency effect. Across three experiments, we found no convincing evidence for a scene-congruency effect or a modulation of scene congruency by scene inversion. These findings question the generalizability of previous observations and cast doubt on whether genuine semantic processing of object-background relationships in scenes can manifest during interocular suppression. © The Author(s) 2016.

HIV-positive MSM's knowledge of HPV and anal cancer self-sampling: A scoping review.

Science.gov (United States)

Poon, M K L; Wong, J P H; Li, A T W; Manuba, M; Bisignano, A; Owino, M; Vahabi, M

2018-02-01

Human papillomavirus (hpv) infection is the cause of anal squamous cell cancer (ascc) in 80% of cases. Available research has also shown high prevalence of anal hpv infection among men who have sex with men (msm). However, hpv vaccination is low among msm in Canada. In light of this information, we conducted a scoping review with the aim of exploring (1) the knowledge of hpv and anal cancer among hiv-positive msm and (2) the acceptability of hpv and anal cancer self-sampling in this population. In conducting the review, we searched five electronic databases for peer-reviewed articles and abstracts published in English, between 2007 and 2017. A total of 803 articles were retrieved; after accounting for duplicates ( n= 40) and unmet criteria ( n= 754), a total of 794 articles were excluded. A final total of nine articles were used in this review. Results of this review show that hiv-positive msm have limited knowledge regarding the risks of anal cancer associated with hiv and hpv coinfection. Furthermore, there is limited research on hpv and anal cancer self-sampling in this population. However, the review of available studies suggested that hiv-positive msm were open to anal cancer self-sampling. It also identified potential barriers to self-sampling. In conclusion, we provide suggestions and future directions for policy-makers and educators to develop inclusive and accessible strategies to reach hiv-positive msm regarding anal cancer education and self-screening.

Anal microbiota profiles in HIV-positive and HIV-negative MSM.

Science.gov (United States)

Yu, Guoqin; Fadrosh, Doug; Ma, Bing; Ravel, Jacques; Goedert, James J

2014-03-13

Because differences in anal microbial populations (microbiota) could affect acquisition of HIV or other conditions, especially among MSM, we profiled the microbiota of the anal canal, assessed its stability, and investigated associations with diversity and composition. Microbiota profiles in anal swabs collected from 76 MSM (52 in 1989, swab-1; 66 1-5 years later, swab-2) were compared by HIV status (25 HIV-positive), T-cell subsets, and questionnaire data. Bacterial 16S rRNA genes were amplified, sequenced (Illumina MiSeq), and clustered into species-level operational taxonomic units (QIIME and Greengenes). Regression models and Wilcoxon tests were used for associations with alpha diversity (unique operational taxonomic units, Shannon's index). Composition was compared by Adonis (QIIME). Most anal bacteria were Firmicutes (mean 60.6%, range 21.1-91.1%) or Bacteroidetes (29.4%, 4.1-70.8%). Alpha diversity did not change between the two swabs (N = 42 pairs). In swab-2, HIV-positives had lower alpha diversity (P ≤ 0.04) and altered composition, with fewer Firmicutes and more Fusobacteria taxa (P ≤ 0.03), not completely attributable to very low CD4(+) cell count (median 232 cells/μl), prior AIDS clinical diagnosis (N = 17), or trimethoprim-sulfamethoxazole use (N = 6). Similar but weaker differences were observed in swab-1 (HIV-positive median 580 CD4(+) cells/μl; no trimethoprim-sulfamethoxazole). Associations with T-cell subsets, smoking, and sexual practices were null or inconsistent. The anal microbiota of MSM was relatively stable over 1-5 years. However, with uncontrolled, advanced HIV infection, the microbiota had altered composition and reduced diversity partially attributable to antibiotics. Investigations of microbial community associations with other immune perturbations and clinical abnormalities are needed.

What drives the US and Peruvian HIV epidemics in men who have sex with men (MSM?

Directory of Open Access Journals (Sweden)

Steven M Goodreau

Full Text Available In this work, we estimate the proportions of transmissions occurring in main vs. casual partnerships, and by the sexual role, infection stage, and testing and treatment history of the infected partner, for men who have sex with men (MSM in the US and Peru. We use dynamic, stochastic models based in exponential random graph models (ERGMs, obtaining inputs from multiple large-scale MSM surveys. Parallel main partnership and casual sexual networks are simulated. Each man is characterized by age, race, circumcision status, sexual role behavior, and propensity for unprotected anal intercourse (UAI; his history is modeled from entry into the adult population, with potential transitions including HIV infection, detection, treatment, AIDS diagnosis, and death. We implemented two model variants differing in assumptions about acute infectiousness, and assessed sensitivity to other key inputs. Our two models suggested that only 4-5% (Model 1 or 22-29% (Model 2 of HIV transmission results from contacts with acute-stage partners; the plurality (80-81% and 49%, respectively stem from chronic-stage partners and the remainder (14-16% and 27-35%, respectively from AIDS-stage partners. Similar proportions of infections stem from partners whose infection is undiagnosed (24-31%, diagnosed but untreated (36-46%, and currently being treated (30-36%. Roughly one-third of infections (32-39% occur within main partnerships. Results by country were qualitatively similar, despite key behavioral differences; one exception was that transmission from the receptive to insertive partner appears more important in Peru (34% than the US (21%. The broad balance in transmission contexts suggests that education about risk, careful assessment, pre-exposure prophylaxis, more frequent testing, earlier treatment, and risk-reduction, disclosure, and adherence counseling may all contribute substantially to reducing the HIV incidence among MSM in the US and Peru.

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

Scene construction in schizophrenia.

Science.gov (United States)

Raffard, Stéphane; D'Argembeau, Arnaud; Bayard, Sophie; Boulenger, Jean-Philippe; Van der Linden, Martial

2010-09-01

Recent research has revealed that schizophrenia patients are impaired in remembering the past and imagining the future. In this study, we examined patients' ability to engage in scene construction (i.e., the process of mentally generating and maintaining a complex and coherent scene), which is a key part of retrieving past experiences and episodic future thinking. 24 participants with schizophrenia and 25 healthy controls were asked to imagine new fictitious experiences and described their mental representations of the scenes in as much detail as possible. Descriptions were scored according to various dimensions (e.g., sensory details, spatial reference), and participants also provided ratings of their subjective experience when imagining the scenes (e.g., their sense of presence, the perceived similarity of imagined events to past experiences). Imagined scenes contained less phenomenological details (d = 1.11) and were more fragmented (d = 2.81) in schizophrenia patients compared to controls. Furthermore, positive symptoms were positively correlated to the sense of presence (r = .43) and the perceived similarity of imagined events to past episodes (r = .47), whereas negative symptoms were negatively related to the overall richness of the imagined scenes (r = -.43). The results suggest that schizophrenic patients' impairments in remembering the past and imagining the future are, at least in part, due to deficits in the process of scene construction. The relationships between the characteristics of imagined scenes and positive and negative symptoms could be related to reality monitoring deficits and difficulties in strategic retrieval processes, respectively. Copyright 2010 APA, all rights reserved.

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…

The {nu}MSM and muon to electron conversion experiments

Energy Technology Data Exchange (ETDEWEB)

Canetti, Laurent, E-mail: laurent.canetti@epfl.ch; Shaposhnikov, Mikhail, E-mail: mikhail.shaposhnikov@epfl.ch [EPFL, ITP (Switzerland)

2013-03-15

We review briefly the different constraints on the three right-handed neutrinos of the {nu}MSM, an extension of the Standard Model that can explain baryon asymmetry, dark matter and neutrino masses. We include in the discussion the proposed experiments on muon to electron conversion Mu2e (Carey et al., Mu2e Collaboration, 2012), COMET and PRISM (Hungerford, COMET Collaboration, AIP Conf Proc 1182:694, 2009; Cui et al., COMET Collaboration, 2012). We find that the expected sensitivity of these experiments is weaker by about two orders of magnitude than the constraints coming from successful baryogenesis.

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,

Estimating the HIV undiagnosed population in Catalonia, Spain: descriptive and comparative data analysis to identify differences in MSM stratified by migrant and Spanish-born population

Science.gov (United States)

Campbell, Colin N J; Vives, Núria; Esteve, Anna; Ambrosioni, Juan; Tural, Cristina; Ferrer, Elena; Navarro, Gemma; Force, Lluis; García, Isabel; Masabeu, Àngels; Vilaró, Josep M; García de Olalla, Patricia; Caylà, Joan Artur; Miró, Josep M; Casabona, Jordi

2018-01-01

Objective Undiagnosed HIV continues to be a hindrance to efforts aimed at reducing incidence of HIV. The objective of this study was to provide an estimate of the HIV undiagnosed population in Catalonia and compare the HIV care cascade with this step included between high-risk populations. Methods To estimate HIV incidence, time between infection and diagnosis and the undiagnosed population stratified by CD4 count, we used the ECDC HIV Modelling Tool V.1.2.2. This model uses data on new HIV and AIDS diagnoses from the Catalan HIV/AIDS surveillance system from 2001 to 2013. Data used to estimate the proportion of people enrolled, on ART and virally suppressed in the HIV care cascade were derived from the PISCIS cohort. Results The total number of people living with HIV (PLHIV) in Catalonia in 2013 was 34 729 (32 740 to 36 827), with 12.3% (11.8 to 18.1) of whom were undiagnosed. By 2013, there were 8458 (8101 to 9079) Spanish-born men who have sex with men (MSM) and 2538 (2334 to 2918) migrant MSM living with HIV in Catalonia. A greater proportion of migrant MSM than local MSM was undiagnosed (32% vs 22%). In the subsequent steps of the HIV care cascade, migrants MSM experience greater losses than the Spanish-born MSM: in retention in care (74% vs 55%), in the proportion on combination antiretroviral treatment (70% vs 50%) and virally suppressed (65% vs 46%). Conclusions By the end of 2013, there were an estimated 34 729 PLHIV in Catalonia, of whom 4271 were still undiagnosed. This study shows that the Catalan epidemic of HIV has continued to expand with the key group sustaining HIV transmission being MSM living with undiagnosed HIV. PMID:29490955

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.

Limited overlap between phylogenetic HIV and hepatitis C virus clusters illustrates the dynamic sexual network structure of Dutch HIV-infected MSM.

Science.gov (United States)

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

2017-09-24

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? A HIV phylogenetic tree was constructed for 5038 HIV-1 subtype B polymerase (pol) sequences obtained from MSM in the AIDS therapy evaluation in the Netherlands cohort. We investigated the existence of HIV clusters with increased HCV prevalence, the HIV phylogenetic density (i.e. the number of potential HIV transmission partners) of HIV/HCV-coinfected MSM compared with HIV-infected MSM without HCV, and the overlap in HIV and HCV phylogenies using HCV nonstructural protein 5B sequences from 183 HIV-infected MSM with acute HCV infection. Five hundred and sixty-three of 5038 (11.2%) HIV-infected MSM tested HCV positive. Phylogenetic analysis revealed 93 large HIV clusters (≥10 MSM), 370 small HIV clusters (2-9 MSM), and 867 singletons with a median HCV prevalence of 11.5, 11.6, and 9.3%, respectively. We identified six large HIV clusters with elevated HCV prevalence (range 23.5-46.2%). Median HIV phylogenetic densities for MSM with HCV (3, interquartile range 1-7) and without HCV (3, interquartile range 1-8) were similar. HCV phylogeny showed 12 MSM-specific HCV clusters (clustersize: 2-39 HCV sequences); 12.7% of HCV infections were part of the same HIV and HCV cluster. We observed few HIV clusters with elevated HCV prevalence, no increase in the HIV phylogenetic density of HIV/HCV-coinfected MSM compared to HIV-infected MSM without HCV, and limited overlap between HIV and HCV phylogenies among HIV/HCV-coinfected MSM. Our data do not support the existence of MSM-specific sexual networks that fuel both the HIV and HCV epidemic.

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.

The νMSM, dark matter and neutrino masses

International Nuclear Information System (INIS)

Asaka, Takehiko; Blanchet, Steve; Shaposhnikov, Mikhail

2005-01-01

We investigate an extension of the Minimal Standard Model by right-handed neutrinos (the νMSM) to incorporate neutrino masses consistent with oscillation experiments. Within this theory, the only candidates for dark matter particles are sterile right-handed neutrinos with masses of a few keV. Requiring that these neutrinos explain entirely the (warm) dark matter, we find that their number is at least three. We show that, in the minimal choice of three sterile neutrinos, the mass of the lightest active neutrino is smaller than O(10 -5 ) eV, which excludes the degenerate mass spectra of three active neutrinos and fixes the absolute mass scale of the other two active neutrinos

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....

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.

Underwater Scene Composition

Science.gov (United States)

Kim, Nanyoung

2009-01-01

In this article, the author describes an underwater scene composition for elementary-education majors. This project deals with watercolor with crayon or oil-pastel resist (medium); the beauty of nature represented by fish in the underwater scene (theme); texture and pattern (design elements); drawing simple forms (drawing skill); and composition…

Increasing condom use and declining STI prevalence in high-risk MSM and TGs: evaluation of a large-scale prevention program in Tamil Nadu, India.

Science.gov (United States)

Subramanian, Thilakavathi; Ramakrishnan, Lakshmi; Aridoss, Santhakumar; Goswami, Prabuddhagopal; Kanguswami, Boopathi; Shajan, Mathew; Adhikary, Rajat; Purushothaman, Girish Kumar Chethrapilly; Ramamoorthy, Senthil Kumar; Chinnaswamy, Eswaramurthy; Veeramani, Ilaya Bharathy; Paranjape, Ramesh Shivram

2013-09-17

This paper presents an evaluation of Avahan, a large scale HIV prevention program that was implemented using peer-mediated strategies, condom distribution and sexually transmitted infection (STI) clinical services among high-risk men who have sex with men (HR-MSM) and male to female transgender persons (TGs) in six high-prevalence state of Tamil Nadu, in southern India. Two rounds of large scale cross-sectional bio-behavioural surveys among HR-MSM and TGs and routine program monitoring data were used to assess changes in program coverage, condom use and prevalence of STIs (including HIV) and their association to program exposure. The Avahan program for HR-MSM and TGs in Tamil Nadu was significantly scaled up and contacts by peer educators reached 77 percent of the estimated denominator by the end of the program's fourth year. Exposure to the program increased between the two rounds of surveys for both HR-MSM (from 66 percent to 90 percent; AOR = 4.6; p Tamil Nadu achieved a high coverage, resulting in improved condom use by HR-MSM with their regular and commercial male partners. Declining STI prevalence and stable HIV prevalence reflect the positive effects of the prevention strategy. Outcomes from the program logic model indiacte the effectiveness of the program for HR-MSM and TGs in Tamil Nadu.

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

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.

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.

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. .

Hepatitis C virus reinfection incidence and treatment outcome among HIV-positive MSM.

Science.gov (United States)

Martin, Thomas C S; Martin, Natasha K; Hickman, Matthew; Vickerman, Peter; Page, Emma E; Everett, Rhiannon; Gazzard, Brian G; Nelson, Mark

2013-10-23

Liver disease secondary to hepatitis C virus (HCV) infection in the context of HIV infection is one of the leading non-AIDS causes of death. Sexual transmission of HCV infection among HIV-positive MSM appears to be leading to increased reports of acute HCV infection. Reinfection after successful treatment or spontaneous clearance is reported among HIV-positive MSM but the scale of reinfection is unknown. We calculate and compare HCV reinfection rates among HIV-positive MSM after spontaneous clearance and successful medical treatment of infection. Retrospective analysis of HIV-positive MSM with sexually acquired HCV who subsequently spontaneously cleared or underwent successful HCV treatment between 2004 and 2012. Among 191 individuals infected with HCV, 44 were reinfected over 562 person-years (py) of follow-up with an overall reinfection rate of 7.8/100 py [95% confidence interval (CI) 5.8-10.5]. Eight individuals were subsequently reinfected a second time at a rate of 15.5/100 py (95% CI 7.7-31.0). Combining all reinfections, 20% resulted in spontaneous clearance and treatment sustained viral response rates were 73% (16/22) for genotypes one and four and 100% (2/2) for genotypes two and three. Among 145 individuals with a documented primary infection, the reinfection rate was 8.0 per 100 py (95% CI 5.7-11.3) overall, 9.6/100 py (95% CI 6.6-14.1) among those successfully treated and 4.2/100 py (95% CI 1.7-10.0) among those who spontaneously cleared. The secondary reinfection rate was 23.2/100 py (95% CI 11.6-46.4). Despite efforts at reducing risk behaviour, HIV-positive MSM who clear HCV infection remain at high risk of reinfection. This emphasizes the need for increased sexual education, surveillance and preventive intervention work.

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.

Substance use and sexual risk behaviors among Peruvian MSM social media users.

Science.gov (United States)

Young, Sean D; Nianogo, Roch A; Chiu, ChingChe J; Menacho, Lucho; Galea, Jerome

2016-01-01

Peru is experiencing a concentrated HIV epidemic among men who have sex with men (MSM). Substance use (alcohol and drug use) has been found to be associated with HIV-related sexual risk behaviors. A recent surge in the number of social media users in Peru has enabled these technologies to be potential tools for reaching HIV at-risk individuals. This study sought to assess the relationship between substance use and sexual risk behaviors among Peruvian MSM who use social media. A total of 556 Peruvian MSM Facebook users (ages 18-59) were recruited to complete a 92-item survey on demographics, sexual risk behaviors, and substance use. We performed a logistic regression of various sexual risk behaviors (e.g., unprotected sex, casual sex) on substance abuse, including alcohol, adjusting for potential covariates. Drinking more than five alcoholic drinks a day in the past three months was associated with an increased odds of having unprotected sex (vaginal and anal) (aOR: 1.52; 95% CL: 1.01, 2.28), casual sex (1.75; 1.17, 2.62), and sex with unknown persons (1.82; 1.23, 2.71). Drug use was not significantly associated with sexual risk behaviors. Among Peruvian MSM social media users, findings suggest that alcohol use was associated with increased HIV-related sexual risk behaviors.

Multiple vehicle routing and dispatching to an emergency scene

OpenAIRE

M S Daskin; A Haghani

1984-01-01

A model of the distribution of arrival time at the scene of an emergency for the first of many vehicles is developed for the case in which travel times on the links of the network are normally distributed and the path travel times of different vehicles are correlated. The model suggests that the probability that the first vehicle arrives at the scene within a given time may be increased by reducing the path time correlations, even if doing so necessitates increasing the mean path travel time ...

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.

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.

Personality traits and mental health states of methamphetamine-dependent and methamphetamine non-using MSM.

Science.gov (United States)

Solomon, Todd M; Kiang, Mathew V; Halkitis, Perry N; Moeller, Robert W; Pappas, Molly K

2010-02-01

This analysis considers the relation between personality traits, mental health states and methamphetamine (MA) use in 60 men who have sex with men (MSM). Thirty MA-dependent and 30 MA non-using MSM were assessed on the Neo Five Factor Inventory, the Brief Symptom Inventory, the Perceived Stress Scale, and the Posttraumatic Stress Disorder Checklist-Civilian Version tests. Our results indicate differences between groups on a variety of measures of personality traits and mental states. Specifically, MA-dependent participants were found to be more Neurotic, less Open, less Agreeable, and less Conscientious. Further, MA-dependent participants were found to have higher levels of Paranoid Ideation and higher levels of Interpersonal Sensitivity. Given the high prevalence of MA use in the MSM community and the association between MA use and sexual risk taking, our findings provided a clearer understanding of how individual personality traits may be a factor in the continued use of this drug among MSM. Further research should seek to incorporate individual personality traits into the development of efficacious MA-specific treatment interventions.

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.

HAART slows progression to anal cancer in HIV-infected MSM.

Science.gov (United States)

Duncan, Katrina C; Chan, Keith J; Chiu, Connie G; Montaner, Julio S G; Coldman, Andy J; Cescon, Angela; Au-Yeung, Christopher G; Wiseman, Sam M; Hogg, Robert S; Press, Natasha M

2015-01-28

Antiretrovirals do not prevent anal intraepithelial neoplasia. However, the influence of antiretrovirals in the natural history of invasive anal cancer is less clear. The objective is to investigate the impact of antiretrovirals in the time to the development of anal cancer in HIV-positive MSM. A retrospective analysis of cases of anal cancer in a cohort of HIV-positive MSM receiving antiretrovirals between 1988 and 2008. Time from first CD4 cell count or HIV RNA viral load test to anal cancer diagnosis was analysed using Cox regression and Kaplan-Meier curves. Anal cancer cases treated in the era prior to HAART (cancer cases (n = 37) were compared with a cohort of 1654 HIV-positive MSM on antiretrovirals. Antiretrovirals were started in the pre-HAART era by 70% of cancer cases, and median CD4 cell count nadir was 70 cells/μl (10-130). Time to development of anal cancer was shorter for cases treated during the pre-HAART era [adjusted hazard ratio (AHR) 3.04, 95% confidence interval (95% CI) 1.48-6.24, P = 0.002], with a CD4 cell count nadir less than 100 cells/μl (AHR 2.21, 95% CI 1.06-4.62, P = 0.035) and longer duration of CD4 cell count less than 100 cells/μl (AHR 1.33, 95% CI 1.11-1.58, P = 0.002). Results show that severe immunosuppression and starting therapy pre-HAART are associated with an increased risk of anal cancer. HIV-positive MSM initiating antiretrovirals during the HAART era (1996-2008) had a longer time to the development of anal cancer than those treated pre-HAART. Our results suggest that early use of HAART may delay progression to anal cancer.

Modular Subsea Monitoring Network (MSM) - Realizing Integrated Environmental Monitoring Solutions

Science.gov (United States)

Mosch, Thomas; Fietzek, Peer

2016-04-01

In a variety of scientific and industrial application areas, ranging i.e. from the supervision of hydrate fields over the detection and localization of fugitive emissions from subsea oil and gas production to fish farming, fixed point observatories are useful and applied means. They monitor the water column and/or are placed at the sea floor over long periods of time. They are essential oceanographic platforms for providing valuable long-term time series data and multi-parameter measurements. Various mooring and observatory endeavors world-wide contribute valuable data needed for understanding our planet's ocean systems and biogeochemical processes. Continuously powered cabled observatories enable real-time data transmission from spots of interest close to the shore or to ocean infrastructures. Independent of the design of the observatories they all rely on sensors which demands for regular maintenance. This work is in most cases associated with cost-intensive maintenance on a regular time basis for the entire sensor carrying fixed platform. It is mandatory to encounter this asset for long-term monitoring by enhancing hardware efficiency. On the basis of two examples of use from the area of hydrate monitoring (off Norway and Japan) we will present the concept of the Modular Subsea Monitoring Network (MSM). The modular, scalable and networking capabilities of the MSM allow for an easy adaptation to different monitoring tasks. Providing intelligent power management, combining chemical and acoustical sensors, adaptation of the payload according to the monitoring tasks, autonomous powering, modular design for easy transportation, storage and mobilization, Vessel of Opportunity-borne launching and recovery capability with a video-guided launcher system and a rope recovery system are key facts addressed during the development of the MSM. Step by step the MSM concept applied to the observatory hardware will also be extended towards the gathered data to maximize the

Estimating the HIV undiagnosed population in Catalonia, Spain: descriptive and comparative data analysis to identify differences in MSM stratified by migrant and Spanish-born population.

Science.gov (United States)

Reyes-Urueña, Juliana Maria; Campbell, Colin N J; Vives, Núria; Esteve, Anna; Ambrosioni, Juan; Tural, Cristina; Ferrer, Elena; Navarro, Gemma; Force, Lluis; García, Isabel; Masabeu, Àngels; Vilaró, Josep M; García de Olalla, Patricia; Caylà, Joan Artur; Miró, Josep M; Casabona, Jordi

2018-02-28

Undiagnosed HIV continues to be a hindrance to efforts aimed at reducing incidence of HIV. The objective of this study was to provide an estimate of the HIV undiagnosed population in Catalonia and compare the HIV care cascade with this step included between high-risk populations. To estimate HIV incidence, time between infection and diagnosis and the undiagnosed population stratified by CD4 count, we used the ECDC HIV Modelling Tool V.1.2.2. This model uses data on new HIV and AIDS diagnoses from the Catalan HIV/AIDS surveillance system from 2001 to 2013. Data used to estimate the proportion of people enrolled, on ART and virally suppressed in the HIV care cascade were derived from the PISCIS cohort. The total number of people living with HIV (PLHIV) in Catalonia in 2013 was 34 729 (32 740 to 36 827), with 12.3% (11.8 to 18.1) of whom were undiagnosed. By 2013, there were 8458 (8101 to 9079) Spanish-born men who have sex with men (MSM) and 2538 (2334 to 2918) migrant MSM living with HIV in Catalonia. A greater proportion of migrant MSM than local MSM was undiagnosed (32% vs 22%). In the subsequent steps of the HIV care cascade, migrants MSM experience greater losses than the Spanish-born MSM: in retention in care (74% vs 55%), in the proportion on combination antiretroviral treatment (70% vs 50%) and virally suppressed (65% vs 46%). By the end of 2013, there were an estimated 34 729 PLHIV in Catalonia, of whom 4271 were still undiagnosed. This study shows that the Catalan epidemic of HIV has continued to expand with the key group sustaining HIV transmission being MSM living with undiagnosed HIV. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Prevalence of drug use during sex amongst MSM in Europe: Results from a multi-site bio-behavioural survey.

Science.gov (United States)

Rosińska, Magdalena; Gios, Lorenzo; Nöstlinger, Christiana; Vanden Berghe, Wim; Marcus, Ulrich; Schink, Susanne; Sherriff, Nigel; Jones, Anna-Marie; Folch, Cinta; Dias, Sonia; Velicko, Inga; Mirandola, Massimo

2018-05-01

Substance use has been consistently reported to be more prevalent amongst Men who have Sex with Men (MSM) compared to the general population. Substance use, in particular polydrug use, has been found to be influenced by social and contextual factors and to increase the risk of unprotected intercourse among MSM. The objective of this analysis was to investigate the prevalence and predictors of drug use during a sexual encounter and to identify specific prevention needs. A multi-site bio-behavioural cross-sectional survey was implemented in 13 European cities, targeting MSM and using Time-Location Sampling and Respondent-Driven Sampling methods Multivariable multi-level logistic random-intercept model (random effect of study site) was estimated to identify factors associated with the use of alcohol, cannabis, party drugs, sexual performance enhancement drugs and chemsex drugs. Overall, 1261 (30.0%) participants reported drug use, and 436 of 3706 (11.8%) reported the use of two or more drugs during their last sexual encounter. By drug class, 966 (23.0%) reported using sexual performance enhancement drugs, 353 (8.4%) - party drugs, and 142 (3.4%) the use of chemsex drugs. Respondents who reported drug use were more frequently diagnosed with HIV (10.5% vs. 3.9%) before and with other STIs during the 12 months prior to the study (16.7% vs. 9.2%). The use of all the analysed substances was significantly associated with sexual encounter with more than one partner. Substance and polydrug use during sexual encounters occurred amongst sampled MSM across Europe although varying greatly between study sites. Different local social norms within MSM communities may be important contextual drivers of drug use, highlighting the need for innovative and multi-faceted prevention measures to reduce HIV/STI risk in the context of drug use. Copyright © 2018 Elsevier B.V. All rights reserved.

What is in a label? Multiple meanings of 'MSM' among same-gender-loving Black men in Mississippi.

Science.gov (United States)

Truong, Nhan; Perez-Brumer, Amaya; Burton, Melissa; Gipson, June; Hickson, DeMarc

2016-01-01

Men who have sex with men (MSM) and other same-gender-loving (SGL) men continue to be disproportionately affected by HIV and AIDS, particularly among the Black population. Innovative strategies are needed to support the health of this community; however, public health efforts primarily approach MSM as a monolithic population erasing the diverse identities, practices, and sexualities within and beyond this category. To better understand diversity within MSM in a geographic region with the largest proportion of Black Americans in the U.S.A. and among the most heavily affected by the epidemic, the Deep South, we conducted four focus groups (n = 29) with Black men who reported having sex with other men residing in Jackson, Mississippi. Results suggest multiple overlapping usages of MSM as identity and behaviour, reflecting internalisation of behavioural categories and co-creation of identities unique to the Black community. These narratives contribute to the literature by documenting the evolving understandings of the category 'MSM' among Black men to reflect intersections between race, socioeconomic status, sexual behaviour, sexuality, subjectivities, and social context. Findings suggest the current monolithic approach to treating MSM may limit public health efforts in developing effective HIV prevention and promotion programmes targeting SGL Black men in the Deep South.

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

The relationship between gender role conflict and condom use among black MSM.

Science.gov (United States)

Malebranche, David J; Gvetadze, Roman; Millett, Gregorio A; Sutton, Madeline Y

2012-10-01

Gender role conflict may influence condom use among black MSM. We examined relationships between the Gender Role Conflict Scale (GRCS), social/demographic variables and condom use among 456 black MSM. Higher total GRCS scores did not predict unprotected insertive anal intercourse (UIAI) or unprotected receptive anal intercourse (URAI) with men, but were associated with unprotected vaginal or anal intercourse (UVI/UAI) with women among bisexually active participants (n = 69). Higher perceived HIV risk reduced the likelihood of both UIAI and URAI with men. Internet recruitment venues, sexual discrimination experiences, higher numbers of sex partners and UVI/UAI with women all increased the likelihood of UIAI with men, while education (college/technical school or college degree) was associated with URAI with men. Future sexual health interventions for black MSM should emphasize broader social/demographic and alternative gender role variables with male sexual partners, while traditional GRCS variables may prove useful among those with female sexual partners.

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.

HIV testing as prevention among MSM in China: the business of scaling-up.

Science.gov (United States)

Fan, Elsa L

2014-01-01

In this paper, I examine the emergence of goumai fuwu, or contracting with social organisations to provide social services, in the HIV/AIDS sector in China. In particular, I interrogate the outsourcing of HIV testing to community-based organisations (CBOs) serving men who have sex with men (MSM) as a means of scaling-up testing in this population, and how the commodification of testing enables new forms of surveillance and citizenship to emerge. In turn, I tie the scaling-up of testing and its commodification to the sustainability of CBOs as they struggle to survive. In recent years, the HIV/AIDS response in China has shifted to expanding testing among MSM in order to reduce new infections. This response has been catalysed by the transition to sexual contact as the primary transmission route for HIV and the rising rates of infection among MSM, leading government institutions and international donors to mobilise CBOs to expand testing. These efforts to scale-up are as much about testing as they are about making visible this hidden population. CBOs, in facilitating testing, come to rely on outsourcing as a long-term funding base and in doing so, unintentionally extend the reach of the state into the everyday lives of MSM.

Research on hyperspectral dynamic scene and image sequence simulation

Science.gov (United States)

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

2016-10-01

This paper presents a simulation method of hyperspectral dynamic scene and image sequence for hyperspectral equipment evaluation and target detection algorithm. Because of high spectral resolution, strong band continuity, anti-interference and other advantages, in recent years, hyperspectral 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 hyperspectral 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 hyperspectral 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, hyperspectral 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 hyperspectral images are consistent with the theoretical analysis results.

The Cannabis Expectancy Questionnaire for Men who have Sex with Men (CEQ-MSM): A measure of substance-related beliefs.

Science.gov (United States)

Mullens, A B; Young, R McD; Dunne, M; Norton, G

2010-06-01

Substance-related expectancies are associated with substance use and post-substance use thoughts, feelings and behaviours. The expectancies held by specific cultural or sub-cultural groups have rarely been investigated. This research maps expectancies specific to gay and other men who have sex with men (MSM) and their relationship with substance patterns and behaviours following use, including sexual practices (e.g., unprotected anal intercourse). This study describes the development of a measure of such beliefs for cannabis, the Cannabis Expectancy Questionnaire for Men who have Sex with Men (CEQ-MSM). Items selected through a focus group and interviews were piloted on 180 self-identified gay or other MSM via an online questionnaire. Factor analysis revealed six distinct substance reinforcement domains ("Enhanced sexual experience", "Sexual negotiation", "Cognitive impairment", "Social and emotional facilitation", "Enhanced sexual desire", and "Sexual inhibition"). The scale was associated with consumption patterns of cannabis, and in a crucial test of discriminant validity not with the consumption of alcohol or stimulants. The CEQ-MSM represents a reliable and valid measure of outcome expectancies, related to cannabis among MSM. Future applications of the CEQ-MSM in health promotion, clinical settings and research may contribute to reducing harm associated with substance use among MSM, including HIV transmission. Copyright 2010 Elsevier Ltd. All rights reserved.

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.

Explaining the Timing of Natural Scene Understanding with a Computational Model of Perceptual Categorization

Science.gov (United States)

Sofer, Imri; Crouzet, Sébastien M.; Serre, Thomas

2015-01-01

Observers can rapidly perform a variety of visual tasks such as categorizing a scene as open, as outdoor, or as a beach. Although we know that different tasks are typically associated with systematic differences in behavioral responses, to date, little is known about the underlying mechanisms. Here, we implemented a single integrated paradigm that links perceptual processes with categorization processes. Using a large image database of natural scenes, we trained machine-learning classifiers to derive quantitative measures of task-specific perceptual discriminability based on the distance between individual images and different categorization boundaries. We showed that the resulting discriminability measure accurately predicts variations in behavioral responses across categorization tasks and stimulus sets. We further used the model to design an experiment, which challenged previous interpretations of the so-called “superordinate advantage.” Overall, our study suggests that observed differences in behavioral responses across rapid categorization tasks reflect natural variations in perceptual discriminability. PMID:26335683

Harassment and Violence Among Men Who Have Sex with Men (MSM) and Hijras After Reinstatement of India's "Sodomy Law".

Science.gov (United States)

Li, Dennis H; Rawat, Shruta; Rhoton, Jayson; Patankar, Pallav; Ekstrand, Maria L; Simon Rosser, B R; Wilkerson, J Michael

2017-09-01

On December 11, 2013, the Indian Supreme Court recriminalized non-peno-vaginal sex under Sec. 377 of the Indian Penal Code (IPC), overturning a 2009 ruling that deemed IPC Sec. 377 unconstitutional. Similar "sodomy laws" in other countries have been associated with increased violence, harassment, and other discrimination against men who have sex with men (MSM) and transgender women. However, few studies have looked at the effects of such a law in an Indian context. This study examined experiences of victimization among MSM and hijra/transgender women (MSM-H) in the State of Maharashtra using a mixed-method approach. Data came from a quantitative survey and qualitative focus groups and interviews from an HIV prevention study as well as qualitative media and case reports from a local MSM-H-serving community-based organization. MSM-H in Maharashtra reported experiencing a high frequency of harassment, violence, and extortion, particularly from male sex partners met online and police. IPC Sec. 377 was implicated across qualitative sources as creating a culture of protection for harassment against MSM-H by being used directly as a tool for harassment, hindering victims of harassment from seeking legal recourse, and adversely impacting HIV and healthcare services. The reinstated IPC Sec. 377 may directly and indirectly facilitate negative health outcomes among MSM-H. Health agencies and advocates should continue to monitor the impact of IPC Sec. 377, incorporate rights-based approaches to protect MSM-H identities while addressing their health and well-being, and explore avenues to initiate discussions with the government to work toward repealing the law.

[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 sexual partners (r = 0.265, χ(2) = 11.422, P sexual behavior in the past 6 months (r = 0.513, χ(2) = 7.442, P sexual orientation in avoidance of being 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.

Measuring population transmission risk for HIV: an alternative metric of exposure risk in men who have sex with men (MSM in the US.

Directory of Open Access Journals (Sweden)

Colleen F Kelley

Full Text Available Various metrics for HIV burden and treatment success [e.g. HIV prevalence, community viral load (CVL, population viral load (PVL, percent of HIV-positive persons with undetectable viral load] have important public health limitations for understanding disparities.Using data from an ongoing HIV incidence cohort of black and white men who have sex with men (MSM, we propose a new metric to measure the prevalence of those at risk of transmitting HIV and illustrate its value. MSM with plasma VL>400 copies/mL were defined as having 'transmission risk'. We calculated HIV prevalence, CVL, PVL, percent of HIV-positive with undetectable viral loads, and prevalence of plasma VL>400 copies/ml (%VL400 for black and white MSM. We used Monte Carlo simulation incorporating data on sexual mixing by race to estimate exposure of black and white HIV-negative MSM to a partner with transmission risk via unprotected anal intercourse (UAI. Of 709 MSM recruited, 42% (168/399 black and 14% (44/310 white MSM tested HIV-positive (p<.0001. No significant differences were seen in CVL, PVL, or percent of HIV positive with undetectable viral loads. The %VL400 was 25% (98/393 for black vs. 8% (25/310 for white MSM (p<.0001. Black MSM with 2 UAI partners were estimated to have 40% probability (95% CI: 35%, 45% of having ≥1 UAI partner with transmission risk vs. 20% for white MSM (CI: 15%, 24%.Despite similarities in other metrics, black MSM in our cohort are three times as likely as white MSM to have HIV transmission risk. With comparable risk behaviors, HIV-negative black MSM have a substantially higher likelihood of encountering a UAI partner at risk of transmitting HIV. Our results support increasing HIV testing, linkage to care, and antiretroviral treatment of HIV-positive MSM to reduce prevalence of those with transmission risk, particularly for black MSM.

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

Directory of Open Access Journals (Sweden)

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.

Distinct contributions of functional and deep neural network features to representational similarity of scenes in human brain and behavior.

Science.gov (United States)

Groen, Iris Ia; Greene, Michelle R; Baldassano, Christopher; Fei-Fei, Li; Beck, Diane M; Baker, Chris I

2018-03-07

Inherent correlations between visual and semantic features in real-world scenes make it difficult to determine how different scene properties contribute to neural representations. Here, we assessed the contributions of multiple properties to scene representation by partitioning the variance explained in human behavioral and brain measurements by three feature models whose inter-correlations were minimized a priori through stimulus preselection. Behavioral assessments of scene similarity reflected unique contributions from a functional feature model indicating potential actions in scenes as well as high-level visual features from a deep neural network (DNN). In contrast, similarity of cortical responses in scene-selective areas was uniquely explained by mid- and high-level DNN features only, while an object label model did not contribute uniquely to either domain. The striking dissociation between functional and DNN features in their contribution to behavioral and brain representations of scenes indicates that scene-selective cortex represents only a subset of behaviorally relevant scene information.

Associative Processing Is Inherent in Scene Perception

Science.gov (United States)

Aminoff, Elissa M.; Tarr, Michael J.

2015-01-01

How are complex visual entities such as scenes represented in the human brain? More concretely, along what visual and semantic dimensions are scenes encoded in memory? One hypothesis is that global spatial properties provide a basis for categorizing the neural response patterns arising from scenes. In contrast, non-spatial properties, such as single objects, also account for variance in neural responses. The list of critical scene dimensions has continued to grow—sometimes in a contradictory manner—coming to encompass properties such as geometric layout, big/small, crowded/sparse, and three-dimensionality. We demonstrate that these dimensions may be better understood within the more general framework of associative properties. That is, across both the perceptual and semantic domains, features of scene representations are related to one another through learned associations. Critically, the components of such associations are consistent with the dimensions that are typically invoked to account for scene understanding and its neural bases. Using fMRI, we show that non-scene stimuli displaying novel associations across identities or locations recruit putatively scene-selective regions of the human brain (the parahippocampal/lingual region, the retrosplenial complex, and the transverse occipital sulcus/occipital place area). Moreover, we find that the voxel-wise neural patterns arising from these associations are significantly correlated with the neural patterns arising from everyday scenes providing critical evidence whether the same encoding principals underlie both types of processing. These neuroimaging results provide evidence for the hypothesis that the neural representation of scenes is better understood within the broader theoretical framework of associative processing. In addition, the results demonstrate a division of labor that arises across scene-selective regions when processing associations and scenes providing better understanding of the functional

Beyond scene gist: Objects guide search more than scene background.

Science.gov (United States)

Koehler, Kathryn; Eckstein, Miguel P

2017-06-01

Although the facilitation of visual search by contextual information is well established, there is little understanding of the independent contributions of different types of contextual cues in scenes. Here we manipulated 3 types of contextual information: object co-occurrence, multiple object configurations, and background category. We isolated the benefits of each contextual cue to target detectability, its impact on decision bias, confidence, and the guidance of eye movements. We find that object-based information guides eye movements and facilitates perceptual judgments more than scene background. The degree of guidance and facilitation of each contextual cue can be related to its inherent informativeness about the target spatial location as measured by human explicit judgments about likely target locations. Our results improve the understanding of the contributions of distinct contextual scene components to search and suggest that the brain's utilization of cues to guide eye movements is linked to the cue's informativeness about the target's location. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

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.

Scene text recognition in mobile applications by character descriptor and structure configuration.

Science.gov (United States)

Yi, Chucai; Tian, Yingli

2014-07-01

Text characters and strings in natural scene can provide valuable information for many applications. Extracting text directly from natural scene images or videos is a challenging task because of diverse text patterns and variant background interferences. This paper proposes a method of scene text recognition from detected text regions. In text detection, our previously proposed algorithms are applied to obtain text regions from scene image. First, we design a discriminative character descriptor by combining several state-of-the-art feature detectors and descriptors. Second, we model character structure at each character class by designing stroke configuration maps. Our algorithm design is compatible with the application of scene text extraction in smart mobile devices. An Android-based demo system is developed to show the effectiveness of our proposed method on scene text information extraction from nearby objects. The demo system also provides us some insight into algorithm design and performance improvement of scene text extraction. The evaluation results on benchmark data sets demonstrate that our proposed scheme of text recognition is comparable with the best existing methods.

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. PMID:24925371

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

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.

When Does Repeated Search in Scenes Involve Memory? Looking at versus Looking for Objects in Scenes

Science.gov (United States)

Vo, Melissa L. -H.; Wolfe, Jeremy M.

2012-01-01

One might assume that familiarity with a scene or previous encounters with objects embedded in a scene would benefit subsequent search for those items. However, in a series of experiments we show that this is not the case: When participants were asked to subsequently search for multiple objects in the same scene, search performance remained…

Driving factors of retention in care among HIV-positive MSM and transwomen in Indonesia: A cross-sectional study

Science.gov (United States)

Erasmus, Vicki; Coulter, Robert W. S.; Koirala, Sushil; Nampaisan, Oranuch; Pamungkas, Wirastra; Richardus, Jan Hendrik

2018-01-01

Little is known about the prevalence of and factors that influence retention in HIV-related care among Indonesian men who have sex with men (MSM) and transgender women (transwomen, or waria in Indonesian term). Therefore, we explored the driving factors of retention in care among HIV-positive MSM and waria in Indonesia. This cross-sectional study involved 298 self-reported HIV-positive MSM (n = 165) and waria (n = 133). Participants were recruited using targeted sampling and interviewed using a structured questionnaire. We applied a four-step model building process using multivariable logistic regression to examine how sociodemographic, predisposing, enabling, and reinforcing factors were associated with retention in care. Overall, 78.5% of participants were linked to HIV care within 3 months after diagnosis or earlier, and 66.4% were adequately retained in care (at least one health care visit every three months once a person is diagnosed with HIV). Being on antiretroviral therapy (adjusted odds ratio [AOR] = 6.00; 95% confidence interval [CI]: 2.93–12.3), using the Internet to find HIV-related information (AOR = 2.15; 95% CI: 1.00–4.59), and having medical insurance (AOR = 2.84; 95% CI: 1.27–6.34) were associated with adequate retention in care. Involvement with an HIV-related organization was associated negatively with retention in care (AOR = 0.47; 95% CI: 0.24–0.95). Future interventions should increase health insurance coverage and utilize the Internet to help MSM and waria to remain in HIV-related care, thereby assisting them in achieving viral suppression. PMID:29342172

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 e-mail (if they were to receive an e-mail notifying them of possible STD 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 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.

The conflation of gender and sex: Gaps and opportunities in HIV data among transgender women and MSM.

Science.gov (United States)

Poteat, Tonia; German, Danielle; Flynn, Colin

2016-01-01

Historically, HIV studies have conflated men who have sex with men (MSM) with transgender (trans) women, explicitly excluded trans individuals, or included sample sizes of trans people that are too small to reach meaningful conclusions. Despite the heavy burden of HIV among trans women, conflation of this population with MSM has limited the information available on the social and behavioural factors that increase HIV vulnerability among trans women and how these factors may differ from MSM. Using data sets from quantitative studies among MSM (n = 645) and trans women (n = 89), as well as qualitative in-depth interviews with 30 trans women in Baltimore, we explore what these data tell us about similarities and differences in HIV vulnerability between the two groups and where they leave gaps in our understanding. We conclude with implications for data collection and intervention development.

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; peffect 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 behaviour at follow-up. The direct effect, however, was not significant. SOLVE is the first intervention to: (1) significantly reduce shame for MSM; and (2) demonstrate that

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.

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.

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

Integrated MSM-FET photoreceiver fabricated on MOCVD grown Hg2-xCdxTe

International Nuclear Information System (INIS)

Leech, P.W.; Gwynn, P.J.; Pain, G.N.; Petkovic, N.R.; Thompson, J.; Jamieson, D.N.

1991-01-01

This paper reports on progress in the monolithic integration of a metal-semiconductor-metal (MSM) detector and transimpedance amplifier and of a photoconductive detector (PCD) with a metal-semiconductor field effect transistor (MESFET) in Hg 1-x Cd x Te. The layers of CdTe/n-type Hg 1-x Cd x Te were grown by MOCVD on semi-insulating GaAs substrates (2 0 misoriented 100). Fabrication of the devices was by an FET planar process; with a standard lift-off used to form Schottky metallization on both the interdigitated electrodes of the MSM detector (2 μm width, 2 μm spacing) and the gate of the MESFETs (5μm length, 100μm width). The MSM photodetectors exhibited breakdown voltages in the range 60 to 80V, a dark current of 10na at 5V bias, and responsivities of >1.0 A/W measured at 40V using CW 1.3 μm illumination

Forensic 3D Scene Reconstruction

International Nuclear Information System (INIS)

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

1999-01-01

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

Remote data acquisition system based on MSM7512B8

International Nuclear Information System (INIS)

Jiang Junfeng

2003-01-01

This paper introduces a remote data acquisition system based on MC68HC908GP32 and MSM7512B, which can accomplish remote data communications on telephone network, and realize remote data acquisition. (authors)

Gordon Craig's Scene Project: a history open to revision

Directory of Open Access Journals (Sweden)

Luiz Fernando

2014-09-01

Full Text Available The article proposes a review of Gordon Craig’s Scene project, an invention patented in 1910 and developed until 1922. Craig himself kept an ambiguous position whether it was an unfulfilled project or not. His son and biographer Edward Craig sustained that Craig’s original aims were never achieved because of technical limitation, and most of the scholars who examined the matter followed this position. Departing from the actual screen models saved in the Bibliothèque Nationale de France, Craig’s original notebooks, and a short film from 1963, I defend that the patented project and the essay published in 1923 mean, indeed, the materialisation of the dreamed device of the thousand scenes in one scene

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.

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 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.

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

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.

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.

Wall grid structure for interior scene synthesis

KAUST Repository

Xu, Wenzhuo; Wang, Bin; Yan, Dongming

2015-01-01

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

Mental health and suicidal ideation among Chinese women who have sex with men who have sex with men (MSM).

Science.gov (United States)

Li, Xianhong; Zhang, Beichuan; Li, Yang; Antonio, Anna Liza Malazarte; Chen, Yunliang; Williams, Ann Bartley

2016-01-01

In China, men who have sex with men (MSM) are the fastest growing population at risk for HIV. They face social stigma due to both MSM behavior and HIV. In addition, concern has been raised about the mental health of wives of MSM. In this cross-sectional study, the authors examine the mental health status of a sample of 135 of these women. Participants completed an Internet-administered questionnaire in Xi'an from April to June, 2012. Most were unaware at the time of marriage that their husbands were MSM. Physical abuse was frequently reported; depressive symptom and mental health (Symptom Checklist, SCL-90) scores were significantly higher than those of the general Chinese adult female population. A majority (59.8%) of women reported suicidal thoughts after discovering their husbands' MSM behavior; about 10% had attempted suicide. Multiple logistic regression revealed that women's experience with anal sex was associated with 7.8 times (95% CI: 1.3-65.9) greater odds of suicidal ideation. Also, women who demonstrated mental symptoms on the SCL-90 had 2.3 times (95% CI: 1.04-5.2) the odds of suicidal ideation. These results suggest that wives of MSM have a significant need for mental health care, suicide prevention, HIV education, and social support.

Eye movements and attention in reading, scene perception, and visual search.

Science.gov (United States)

Rayner, Keith

2009-08-01

Eye movements are now widely used to investigate cognitive processes during reading, scene perception, and visual search. In this article, research on the following topics is reviewed with respect to reading: (a) the perceptual span (or span of effective vision), (b) preview benefit, (c) eye movement control, and (d) models of eye movements. Related issues with respect to eye movements during scene perception and visual search are also reviewed. It is argued that research on eye movements during reading has been somewhat advanced over research on eye movements in scene perception and visual search and that some of the paradigms developed to study reading should be more widely adopted in the study of scene perception and visual search. Research dealing with "real-world" tasks and research utilizing the visual-world paradigm are also briefly discussed.

Range sections as rock models for intensity rock scene segmentation

CSIR Research Space (South Africa)

Mkwelo, S

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...

Substance use in the MSM population of New York City during the era of HIV/AIDS.

Science.gov (United States)

Halkitis, Perry N; Pollock, James A; Pappas, Molly K; Dayton, Alex; Moeller, Robert W; Siconolfi, Daniel; Solomon, Todd

2011-01-01

This literature review considers the historical significance, emergence of, and interplay between the HIV and illicit drug use epidemics among gay, bisexual, and other men who have sex with men (MSM) in New York City (NYC). The continual rise in HIV infections in recent years among MSM, particularly among young MSM (YMSM), commands a need for the examination of the effectiveness of current HIV prevention strategies and a more comprehensive understanding of the complex biopsychosocial influences that place YMSM at risk. A chronological perspective of both the HIV and illicit drug use epidemics affecting NYC MSM is presented, followed by a review of the existing research on the synergistic relation between the two. Special consideration is given to the patterns and interconnectivity between HIV, substance use, and housing instability specific to YMSM, as they represent the demographic currently at greatest risk for HIV transmission in NYC. Thereafter, an overview of treatment research is provided. We conclude by offering recommendations for future research and best practices as we move forward in an attempt to reduce the incidence of HIV transmission.

Reconstruction of measurable three-dimensional point cloud model based on large-scene archaeological excavation sites

Science.gov (United States)

Zhang, Chun-Sen; Zhang, Meng-Meng; Zhang, Wei-Xing

2017-01-01

This paper outlines a low-cost, user-friendly photogrammetric technique with nonmetric cameras to obtain excavation site digital sequence images, based on photogrammetry and computer vision. Digital camera calibration, automatic aerial triangulation, image feature extraction, image sequence matching, and dense digital differential rectification are used, combined with a certain number of global control points of the excavation site, to reconstruct the high precision of measured three-dimensional (3-D) models. Using the acrobatic figurines in the Qin Shi Huang mausoleum excavation as an example, our method solves the problems of little base-to-height ratio, high inclination, unstable altitudes, and significant ground elevation changes affecting image matching. Compared to 3-D laser scanning, the 3-D color point cloud obtained by this method can maintain the same visual result and has advantages of low project cost, simple data processing, and high accuracy. Structure-from-motion (SfM) is often used to reconstruct 3-D models of large scenes and has lower accuracy if it is a reconstructed 3-D model of a small scene at close range. Results indicate that this method quickly achieves 3-D reconstruction of large archaeological sites and produces heritage site distribution of orthophotos providing a scientific basis for accurate location of cultural relics, archaeological excavations, investigation, and site protection planning. This proposed method has a comprehensive application value.

Lateralized discrimination of emotional scenes in peripheral vision.

Science.gov (United States)

Calvo, Manuel G; Rodríguez-Chinea, Sandra; Fernández-Martín, Andrés

2015-03-01

This study investigates whether there is lateralized processing of emotional scenes in the visual periphery, in the absence of eye fixations; and whether this varies with emotional valence (pleasant vs. unpleasant), specific emotional scene content (babies, erotica, human attack, mutilation, etc.), and sex of the viewer. Pairs of emotional (positive or negative) and neutral photographs were presented for 150 ms peripherally (≥6.5° away from fixation). Observers judged on which side the emotional picture was located. Low-level image properties, scene visual saliency, and eye movements were controlled. Results showed that (a) correct identification of the emotional scene exceeded the chance level; (b) performance was more accurate and faster when the emotional scene appeared in the left than in the right visual field; (c) lateralization was equivalent for females and males for pleasant scenes, but was greater for females and unpleasant scenes; and (d) lateralization occurred similarly for different emotional scene categories. These findings reveal discrimination between emotional and neutral scenes, and right brain hemisphere dominance for emotional processing, which is modulated by sex of the viewer and scene valence, and suggest that coarse affective significance can be extracted in peripheral vision.

Training Small Networks for Scene Classification of Remote Sensing Images via Knowledge Distillation

Directory of Open Access Journals (Sweden)

Guanzhou Chen

2018-05-01

Full Text Available Scene classification, aiming to identify the land-cover categories of remotely sensed image patches, is now a fundamental task in the remote sensing image analysis field. Deep-learning-model-based algorithms are widely applied in scene classification and achieve remarkable performance, but these high-level methods are computationally expensive and time-consuming. Consequently in this paper, we introduce a knowledge distillation framework, currently a mainstream model compression method, into remote sensing scene classification to improve the performance of smaller and shallower network models. Our knowledge distillation training method makes the high-temperature softmax output of a small and shallow student model match the large and deep teacher model. In our experiments, we evaluate knowledge distillation training method for remote sensing scene classification on four public datasets: AID dataset, UCMerced dataset, NWPU-RESISC dataset, and EuroSAT dataset. Results show that our proposed training method was effective and increased overall accuracy (3% in AID experiments, 5% in UCMerced experiments, 1% in NWPU-RESISC and EuroSAT experiments for small and shallow models. We further explored the performance of the student model on small and unbalanced datasets. Our findings indicate that knowledge distillation can improve the performance of small network models on datasets with lower spatial resolution images, numerous categories, as well as fewer training samples.

Estimating cotton canopy ground cover from remotely sensed scene reflectance

International Nuclear Information System (INIS)

Maas, S.J.

1998-01-01

Many agricultural applications require spatially distributed information on growth-related crop characteristics that could be supplied through aircraft or satellite remote sensing. A study was conducted to develop and test a methodology for estimating plant canopy ground cover for cotton (Gossypium hirsutum L.) from scene reflectance. Previous studies indicated that a relatively simple relationship between ground cover and scene reflectance could be developed based on linear mixture modeling. Theoretical analysis indicated that the effects of shadows in the scene could be compensated for by averaging the results obtained using scene reflectance in the red and near-infrared wavelengths. The methodology was tested using field data collected over several years from cotton test plots in Texas and California. Results of the study appear to verify the utility of this approach. Since the methodology relies on information that can be obtained solely through remote sensing, it would be particularly useful in applications where other field information, such as plant size, row spacing, and row orientation, is unavailable

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

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.

Binary patterns encoded convolutional neural networks for texture recognition and remote sensing scene classification

Science.gov (United States)

Anwer, Rao Muhammad; Khan, Fahad Shahbaz; van de Weijer, Joost; Molinier, Matthieu; Laaksonen, Jorma

2018-04-01

Designing discriminative powerful texture features robust to realistic imaging conditions is a challenging computer vision problem with many applications, including material recognition and analysis of satellite or aerial imagery. In the past, most texture description approaches were based on dense orderless statistical distribution of local features. However, most recent approaches to texture recognition and remote sensing scene classification are based on Convolutional Neural Networks (CNNs). The de facto practice when learning these CNN models is to use RGB patches as input with training performed on large amounts of labeled data (ImageNet). In this paper, we show that Local Binary Patterns (LBP) encoded CNN models, codenamed TEX-Nets, trained using mapped coded images with explicit LBP based texture information provide complementary information to the standard RGB deep models. Additionally, two deep architectures, namely early and late fusion, are investigated to combine the texture and color information. To the best of our knowledge, we are the first to investigate Binary Patterns encoded CNNs and different deep network fusion architectures for texture recognition and remote sensing scene classification. We perform comprehensive experiments on four texture recognition datasets and four remote sensing scene classification benchmarks: UC-Merced with 21 scene categories, WHU-RS19 with 19 scene classes, RSSCN7 with 7 categories and the recently introduced large scale aerial image dataset (AID) with 30 aerial scene types. We demonstrate that TEX-Nets provide complementary information to standard RGB deep model of the same network architecture. Our late fusion TEX-Net architecture always improves the overall performance compared to the standard RGB network on both recognition problems. Furthermore, our final combination leads to consistent improvement over the state-of-the-art for remote sensing scene classification.

Learning object-to-class kernels for scene classification.

Science.gov (United States)

Zhang, Lei; Zhen, Xiantong; Shao, Ling

2014-08-01

High-level image representations have drawn increasing attention in visual recognition, e.g., scene classification, since the invention of the object bank. The object bank represents an image as a response map of a large number of pretrained object detectors and has achieved superior performance for visual recognition. In this paper, based on the object bank representation, we propose the object-to-class (O2C) distances to model scene images. In particular, four variants of O2C distances are presented, and with the O2C distances, we can represent the images using the object bank by lower-dimensional but more discriminative spaces, called distance spaces, which are spanned by the O2C distances. Due to the explicit computation of O2C distances based on the object bank, the obtained representations can possess more semantic meanings. To combine the discriminant ability of the O2C distances to all scene classes, we further propose to kernalize the distance representation for the final classification. We have conducted extensive experiments on four benchmark data sets, UIUC-Sports, Scene-15, MIT Indoor, and Caltech-101, which demonstrate that the proposed approaches can significantly improve the original object bank approach and achieve the state-of-the-art performance.

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.

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

Iconic memory for the gist of natural scenes.

Science.gov (United States)

Clarke, Jason; Mack, Arien

2014-11-01

Does iconic memory contain the gist of multiple scenes? Three experiments were conducted. In the first, four scenes from different basic-level categories were briefly presented in one of two conditions: a cue or a no-cue condition. The cue condition was designed to provide an index of the contents of iconic memory of the display. Subjects were more sensitive to scene gist in the cue condition than in the no-cue condition. In the second, the scenes came from the same basic-level category. We found no difference in sensitivity between the two conditions. In the third, six scenes from different basic level categories were presented in the visual periphery. Subjects were more sensitive to scene gist in the cue condition. These results suggest that scene gist is contained in iconic memory even in the visual periphery; however, iconic representations are not sufficiently detailed to distinguish between scenes coming from the same category. Copyright © 2014 Elsevier Inc. All rights reserved.

Poppers use and Sexual Partner Concurrency Increase the HIV Incidence of MSM: a 24-month Prospective Cohort Survey in Shenyang, China.

Science.gov (United States)

Chu, Zhen-Xing; Xu, Jun-Jie; Zhang, Yong-Hui; Zhang, Jing; Hu, Qing-Hai; Yun, Ke; Wang, Hong-Yi; Jiang, Yong-Jun; Geng, Wen-Qing; Shang, Hong

2018-01-08

The use of poppers is highly prevalent in MSM, but little is known about the association between their use and HIV incidence in China. A prospective cohort study was conducted from 2011 to 2013 in MSM in Shenyang. 475(79.6%) of eligible HIV-negative MSM participated in this prospective survey and near one fourth MSM (23.4%) ever used poppers. About one-third of the participants had condomless anal intercourse, half had multiple sexual partners and 10.5% were syphilis positive. The HIV incidence densities were15.5 (95% CI:9.4-23.4)/100 PY[person-years]) and 4.6 (95% CI:2.9-7.0)/100 PY in poppers-users and non-poppers-users, respectively. Predictors of HIV seroconversion included poppers-using-behavior, having had more than two male partners, practicing group sex, unprotected anal intercourse(UAI) with male partners, and baseline syphilis positivity (all P poppers, high-risk-sexual behaviors and syphilis infection significantly increase the HIV incidence among Shenyang MSM. It is essential for policy makers to add poppers to the official controlled illicit drug list to reduce HIV transmission among the MSM community. A comprehensive strategy should also be implemented to control both their high-risk-sexual behaviors and risk of syphilis infection, since these may represent novel ways to prevent new HIV infections in these MSM.

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

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.

Narrative Collage of Image Collections by Scene Graph Recombination.

Science.gov (United States)

Fang, Fei; Yi, Miao; Feng, Hui; Hu, Shenghong; Xiao, Chunxia

2017-10-04

Narrative collage is an interesting image editing art to summarize the main theme or storyline behind an image collection. We present a novel method to generate narrative images with plausible semantic scene structures. To achieve this goal, we introduce a layer graph and a scene graph to represent relative depth order and semantic relationship between image objects, respectively. We firstly cluster the input image collection to select representative images, and then extract a group of semantic salient objects from each representative image. Both Layer graphs and scene graphs are constructed and combined according to our specific rules for reorganizing the extracted objects in every image. We design an energy model to appropriately locate every object on the final canvas. Experiment results show that our method can produce competitive narrative collage result and works well on a wide range of image collections.

Virtual environments for scene of crime reconstruction and analysis

Science.gov (United States)

Howard, Toby L. J.; Murta, Alan D.; Gibson, Simon

2000-02-01

This paper describes research conducted in collaboration with Greater Manchester Police (UK), to evalute the utility of Virtual Environments for scene of crime analysis, forensic investigation, and law enforcement briefing and training. We present an illustrated case study of the construction of a high-fidelity virtual environment, intended to match a particular real-life crime scene as closely as possible. We describe and evaluate the combination of several approaches including: the use of the Manchester Scene Description Language for constructing complex geometrical models; the application of a radiosity rendering algorithm with several novel features based on human perceptual consideration; texture extraction from forensic photography; and experiments with interactive walkthroughs and large-screen stereoscopic display of the virtual environment implemented using the MAVERIK system. We also discuss the potential applications of Virtual Environment techniques in the Law Enforcement and Forensic communities.

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.

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...

Significance of perceptually relevant image decolorization for scene classification

Science.gov (United States)

Viswanathan, Sowmya; Divakaran, Govind; Soman, Kutti Padanyl

2017-11-01

Color images contain luminance and chrominance components representing the intensity and color information, respectively. The objective of this paper is to show the significance of incorporating chrominance information to the task of scene classification. An improved color-to-grayscale image conversion algorithm that effectively incorporates chrominance information is proposed using the color-to-gray structure similarity index and singular value decomposition to improve the perceptual quality of the converted grayscale images. The experimental results based on an image quality assessment for image decolorization and its success rate (using the Cadik and COLOR250 datasets) show that the proposed image decolorization technique performs better than eight existing benchmark algorithms for image decolorization. In the second part of the paper, the effectiveness of incorporating the chrominance component for scene classification tasks is demonstrated using a deep belief network-based image classification system developed using dense scale-invariant feature transforms. The amount of chrominance information incorporated into the proposed image decolorization technique is confirmed with the improvement to the overall scene classification accuracy. Moreover, the overall scene classification performance improved by combining the models obtained using the proposed method and conventional decolorization methods.

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.

Signature modelling and radiometric rendering equations in infrared scene simulation systems

CSIR Research Space (South Africa)

Willers, CJ

2011-09-01

Full Text Available The development and optimisation of modern infrared systems necessitates the use of simulation systems to create radiometrically realistic representations (e.g. images) of infrared scenes. Such simulation systems are used in signature prediction...

Albedo estimation for scene segmentation

Energy Technology Data Exchange (ETDEWEB)

Lee, C H; Rosenfeld, A

1983-03-01

Standard methods of image segmentation do not take into account the three-dimensional nature of the underlying scene. For example, histogram-based segmentation tacitly assumes that the image intensity is piecewise constant, and this is not true when the scene contains curved surfaces. This paper introduces a method of taking 3d information into account in the segmentation process. The image intensities are adjusted to compensate for the effects of estimated surface orientation; the adjusted intensities can be regarded as reflectivity estimates. When histogram-based segmentation is applied to these new values, the image is segmented into parts corresponding to surfaces of constant reflectivity in the scene. 7 references.

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

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...... are in accordance with findings in other European outbreaks. As the general immunity to hepatitis A decreases and the outbreak potential increases, we recommend health education and hepatitis A vaccination to all MSM not living in monogamous relationships, especially if they visit gay saunas or other places...

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.

Pooling Objects for Recognizing Scenes without Examples

NARCIS (Netherlands)

Kordumova, S.; Mensink, T.; Snoek, C.G.M.

2016-01-01

In this paper we aim to recognize scenes in images without using any scene images as training data. Different from attribute based approaches, we do not carefully select the training classes to match the unseen scene classes. Instead, we propose a pooling over ten thousand of off-the-shelf object

The trouble with "MSM" and "WSW": erasure of the sexual-minority person in public health discourse.

Science.gov (United States)

Young, Rebecca M; Meyer, Ilan H

2005-07-01

Men who have sex with men (MSM) and women who have sex with women (WSW) are purportedly neutral terms commonly used in public health discourse. However, they are problematic because they obscure social dimensions of sexuality; undermine the self-labeling of lesbian, gay, and bisexual people; and do not sufficiently describe variations in sexual behavior.MSM and WSW often imply a lack of lesbian or gay identity and an absence of community, networks, and relationships in which same-gender pairings mean more than merely sexual behavior. Overuse of the terms MSM and WSW adds to a history of scientific labeling of sexual minorities that reflects, and inadvertently advances, heterosexist notions. Public health professionals should adopt more nuanced and culturally relevant language in discussing members of sexual-minority groups.

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.

Review of On-Scene Management of Mass-Casualty Attacks

Directory of Open Access Journals (Sweden)

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

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.

Neural Scene Segmentation by Oscillatory Correlation

National Research Council Canada - National Science Library

Wang, DeLiang

2000-01-01

The segmentation of a visual scene into a set of coherent patterns (objects) is a fundamental aspect of perception, which underlies a variety of important tasks such as figure/ground segregation, and scene analysis...

A hierarchical inferential method for indoor scene classification

Directory of Open Access Journals (Sweden)

Jiang Jingzhe

2017-12-01

Full Text Available Indoor scene classification forms a basis for scene interaction for service robots. The task is challenging because the layout and decoration of a scene vary considerably. Previous studies on knowledge-based methods commonly ignore the importance of visual attributes when constructing the knowledge base. These shortcomings restrict the performance of classification. The structure of a semantic hierarchy was proposed to describe similarities of different parts of scenes in a fine-grained way. Besides the commonly used semantic features, visual attributes were also introduced to construct the knowledge base. Inspired by the processes of human cognition and the characteristics of indoor scenes, we proposed an inferential framework based on the Markov logic network. The framework is evaluated on a popular indoor scene dataset, and the experimental results demonstrate its effectiveness.

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.

Visual search for arbitrary objects in real scenes

Science.gov (United States)

Alvarez, George A.; Rosenholtz, Ruth; Kuzmova, Yoana I.; Sherman, Ashley M.

2011-01-01

How efficient is visual search in real scenes? In searches for targets among arrays of randomly placed distractors, efficiency is often indexed by the slope of the reaction time (RT) × Set Size function. However, it may be impossible to define set size for real scenes. As an approximation, we hand-labeled 100 indoor scenes and used the number of labeled regions as a surrogate for set size. In Experiment 1, observers searched for named objects (a chair, bowl, etc.). With set size defined as the number of labeled regions, search was very efficient (~5 ms/item). When we controlled for a possible guessing strategy in Experiment 2, slopes increased somewhat (~15 ms/item), but they were much shallower than search for a random object among other distinctive objects outside of a scene setting (Exp. 3: ~40 ms/item). In Experiments 4–6, observers searched repeatedly through the same scene for different objects. Increased familiarity with scenes had modest effects on RTs, while repetition of target items had large effects (>500 ms). We propose that visual search in scenes is efficient because scene-specific forms of attentional guidance can eliminate most regions from the “functional set size” of items that could possibly be the target. PMID:21671156

Visual search for arbitrary objects in real scenes.

Science.gov (United States)

Wolfe, Jeremy M; Alvarez, George A; Rosenholtz, Ruth; Kuzmova, Yoana I; Sherman, Ashley M

2011-08-01

How efficient is visual search in real scenes? In searches for targets among arrays of randomly placed distractors, efficiency is often indexed by the slope of the reaction time (RT) × Set Size function. However, it may be impossible to define set size for real scenes. As an approximation, we hand-labeled 100 indoor scenes and used the number of labeled regions as a surrogate for set size. In Experiment 1, observers searched for named objects (a chair, bowl, etc.). With set size defined as the number of labeled regions, search was very efficient (~5 ms/item). When we controlled for a possible guessing strategy in Experiment 2, slopes increased somewhat (~15 ms/item), but they were much shallower than search for a random object among other distinctive objects outside of a scene setting (Exp. 3: ~40 ms/item). In Experiments 4-6, observers searched repeatedly through the same scene for different objects. Increased familiarity with scenes had modest effects on RTs, while repetition of target items had large effects (>500 ms). We propose that visual search in scenes is efficient because scene-specific forms of attentional guidance can eliminate most regions from the "functional set size" of items that could possibly be the target.

An Examination of HPV16 Natural Immunity in Men Who Have Sex with Men (MSM) in the HPV in Men (HIM) Study.

Science.gov (United States)

Beachler, Daniel C; Pinto, Ligia A; Kemp, Troy J; Nyitray, Alan G; Hildesheim, Allan; Viscidi, Raphael; Schussler, John; Kreimer, Aimée R; Giuliano, Anna R

2018-04-01

Background: Evidence suggests that natural antibodies developed after HPV16 infection may protect some women but not men against subsequent HPV16 reacquisition. Less is known whether antibodies developed following HPV16 infection are protective among men who have sex with men (MSM). Methods: Four hundred seventy-five MSM from the Human Papillomavirus Infection in Men (HIM) study were tested for serum antibodies to HPV16 L1 using enzyme-linked immunosorbent assays, and for anal and genital HPV16 DNA using PCR consensus primer system (PGMY 09/11). Adjusted Cox regression was used to evaluate whether baseline HPV16 seropositivity impacts subsequent genital or anal HPV16 DNA. Results: The risk of subsequent genital HPV16 [aHR = 1.05, 95% confidence interval (CI) = 0.66-1.68] and anal HPV16 infections among MSM (aHR = 2.34, 95% CI = 0.92-5.98) was similar or nonsignificantly higher in HPV16-seropositive than HPV16-seronegative MSM. The risk of genital HPV16 was also similar between HPV16-seronegative and HPV16-seropositive MSM in the highest tertile of HPV16 antibody levels and when restricting to those with new sex partners during follow-up ( P > 0.20). Among the 118 MSM who were HPV16 seropositive, 90% remained HPV16 seropositive up to 4 years later. When tested together, MSM with the highest antibody titers (top tertile) had similar levels to females (mean = 130.3 vs. 134.5 EU/mL, P = 0.84). Conclusions: Despite years of HPV16 seropositivity persistence and antibody titers comparable with females, this study suggested no evidence of HPV16 natural antibodies protecting against subsequent genital or anal HPV16 infection in MSM. Impact: This could help partially explain the high incidence of genital and anal HPV16 infection and related anal cancer seen in middle-aged and older MSM. Cancer Epidemiol Biomarkers Prev; 27(4); 496-502. ©2018 AACR . ©2018 American Association for Cancer Research.

Land-use Scene Classification in High-Resolution Remote Sensing Images by Multiscale Deeply Described Correlatons

Science.gov (United States)

Qi, K.; Qingfeng, G.

2017-12-01

With the popular use of High-Resolution Satellite (HRS) images, more and more research efforts have been placed on land-use scene classification. However, it makes the task difficult with HRS images for the complex background and multiple land-cover classes or objects. This article presents a multiscale deeply described correlaton model for land-use scene classification. Specifically, the convolutional neural network is introduced to learn and characterize the local features at different scales. Then, learnt multiscale deep features are explored to generate visual words. The spatial arrangement of visual words is achieved through the introduction of adaptive vector quantized correlograms at different scales. Experiments on two publicly available land-use scene datasets demonstrate that the proposed model is compact and yet discriminative for efficient representation of land-use scene images, and achieves competitive classification results with the state-of-art methods.

Scene analysis in the natural environment

DEFF Research Database (Denmark)

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

2014-01-01

The problem of scene analysis has been studied in a number of different fields over the past decades. These studies have led to important insights into problems of scene analysis, but not all of these insights are widely appreciated, and there remain critical shortcomings in current approaches th...... 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 toward behavioral goals....

The time course of natural scene perception with reduced attention.

Science.gov (United States)

Groen, Iris I A; Ghebreab, Sennay; Lamme, Victor A F; Scholte, H Steven

2016-02-01

Attention is thought to impose an informational bottleneck on vision by selecting particular information from visual scenes for enhanced processing. Behavioral evidence suggests, however, that some scene information is extracted even when attention is directed elsewhere. Here, we investigated the neural correlates of this ability by examining how attention affects electrophysiological markers of scene perception. In two electro-encephalography (EEG) experiments, human subjects categorized real-world scenes as manmade or natural (full attention condition) or performed tasks on unrelated stimuli in the center or periphery of the scenes (reduced attention conditions). Scene processing was examined in two ways: traditional trial averaging was used to assess the presence of a categorical manmade/natural distinction in event-related potentials, whereas single-trial analyses assessed whether EEG activity was modulated by scene statistics that are diagnostic of naturalness of individual scenes. The results indicated that evoked activity up to 250 ms was unaffected by reduced attention, showing intact categorical differences between manmade and natural scenes and strong modulations of single-trial activity by scene statistics in all conditions. Thus initial processing of both categorical and individual scene information remained intact with reduced attention. Importantly, however, attention did have profound effects on later evoked activity; full attention on the scene resulted in prolonged manmade/natural differences, increased neural sensitivity to scene statistics, and enhanced scene memory. These results show that initial processing of real-world scene information is intact with diminished attention but that the depth of processing of this information does depend on attention. Copyright © 2016 the American Physiological Society.

[Molecular epidemiological characteristics of HIV-1 strains isolated from newly diagnosed MSM subjects (2006-2010) in Beijing, China].

Science.gov (United States)

Ye, Jing-Rong; Zang, Wan-Chun; Su, Xue-Li; Lu, Hong-Yan; Hao, Ming-Qiang; Xin, Ruo-Lei; Chen, Guo-Min; He, Xiong; Zeng, Yi

2014-03-01

This study aims to analyze the molecular epidemiological characteristics of HIV-1 strains prevailing among men who have sex with men (MSM) in Beijing, China. The pol gene fragments from 250 newly diagnosed HIV-1-infected MSM individuals during 2006-2010 in Beijing were amplified by RT-nested PCR, sequenced, and phylogenetically analyzed. HIV-1 pol gene from 189 individuals were amplified and analyzed; 81 (42. 9%), 3 (1. 6%), 2 (1.0%), 88 (46. 6%), and 15 (7.9%) individuals were infected with HIV-1 subtypes B, B', C, CRF01_AE, and CRF07_BC, respectively. The subtypes B and CRF01_AE could both be grouped into two clusters, and CRFO7_BC strains shared high homology and were presumed to originate from a common ancestor. The HIV-1 circulating in MSM in Beijing had a lower genetic diversity than in heterosexuals. The HIV-1 epidemic (2006-2010) in MSM in Beijing was actually a rapid spread of HIV-1 CRF01 AE and B, or rather native strains of the two viruses.

Self-Perceived Viral Load and Sexual Risk Behavior Among Known HIV-Positive MSM in San Francisco, 2014.

Science.gov (United States)

Guigayoma, John; Chen, Yea-Hung; Snowden, Jonathan M; Santos, Glenn-Milo; Hecht, Jennifer; Raymond, H Fisher

2017-07-01

Self-perceived viral suppression status among men who have sex with men (MSM) may impact HIV risk transmission behaviors. We conducted a 2014 cross-sectional survey of MSM in San Francisco and assessed differences in sexual risk behavior among known HIV-positive MSM based on viral suppression of HIV. We collected demographics, self-perceived viral load status, and sexual risk behavior and tested for viral load levels through laboratory assays. Men were categorized in a hierarchical schema of sexual risk behavior categories based on responses to questions regarding recent partners' HIV status, condom use, and sexual positioning. We used Fisher exact tests to assess for differences based on self-perceived viral load status. Out of a sample of 96 known HIV-positive men, 59 men self-reported an undetectable HIV viral load and 9 men self-reported a detectable viral load consented to confirmatory laboratory testing. The sample of self-reported undetectable men had gradually larger proportions of higher-risk sexual practices, whereas the sample of detectable men was evenly distributed across sexual practices. This association was not statistically significant (P = 0.91). Self-perceived viral suppression may influence sexual practices of known HIV-positive MSM, but small sample size, especially within the detectable category, hinders our ability to determine statistical significance. More research is necessary to assess how HIV-positive men account for viral load in sexual decision-making practices, and this research may inform resource allocation and clinical recommendations to maintain the health of MSM populations.

Scene recognition based on integrating active learning with dictionary learning

Science.gov (United States)

Wang, Chengxi; Yin, Xueyan; Yang, Lin; Gong, Chengrong; Zheng, Caixia; Yi, Yugen

2018-04-01

Scene recognition is a significant topic in the field of computer vision. Most of the existing scene recognition models require a large amount of labeled training samples to achieve a good performance. However, labeling image manually is a time consuming task and often unrealistic in practice. In order to gain satisfying recognition results when labeled samples are insufficient, this paper proposed a scene recognition algorithm named Integrating Active Learning and Dictionary Leaning (IALDL). IALDL adopts projective dictionary pair learning (DPL) as classifier and introduces active learning mechanism into DPL for improving its performance. When constructing sampling criterion in active learning, IALDL considers both the uncertainty and representativeness as the sampling criteria to effectively select the useful unlabeled samples from a given sample set for expanding the training dataset. Experiment results on three standard databases demonstrate the feasibility and validity of the proposed IALDL.

Interaction between scene-based and array-based contextual cueing.

Science.gov (United States)

Rosenbaum, Gail M; Jiang, Yuhong V

2013-07-01

Contextual cueing refers to the cueing of spatial attention by repeated spatial context. Previous studies have demonstrated distinctive properties of contextual cueing by background scenes and by an array of search items. Whereas scene-based contextual cueing reflects explicit learning of the scene-target association, array-based contextual cueing is supported primarily by implicit learning. In this study, we investigated the interaction between scene-based and array-based contextual cueing. Participants searched for a target that was predicted by both the background scene and the locations of distractor items. We tested three possible patterns of interaction: (1) The scene and the array could be learned independently, in which case cueing should be expressed even when only one cue was preserved; (2) the scene and array could be learned jointly, in which case cueing should occur only when both cues were preserved; (3) overshadowing might occur, in which case learning of the stronger cue should preclude learning of the weaker cue. In several experiments, we manipulated the nature of the contextual cues present during training and testing. We also tested explicit awareness of scenes, scene-target associations, and arrays. The results supported the overshadowing account: Specifically, scene-based contextual cueing precluded array-based contextual cueing when both were predictive of the location of a search target. We suggest that explicit, endogenous cues dominate over implicit cues in guiding spatial attention.

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.

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...... is a promising method for distinction of MSM types, but further validation is needed. In order to improve methods for MSM identification, specifically designed studies for the collection of data obtained by standardised methods on indicators such as calcium and cholesterol should be undertaken, while studies...

The Mpumalanga Men's Study (MPMS: results of a baseline biological and behavioral HIV surveillance survey in two MSM communities in South Africa.

Directory of Open Access Journals (Sweden)

Tim Lane

Full Text Available The Mpumalanga Men's Study (MPMS is the assessment of the Project Boithato HIV prevention intervention for South African MSM. Boithato aims to increase consistent condom use, regular testing for HIV-negative MSM, and linkage to care for HIV-positive MSM. The MPMS baseline examined HIV prevalence and associated risk behaviors, and testing, care, and treatment behaviors among MSM in Gert Sibande and Ehlanzeni districts in Mpumalanga province, South Africa in order to effectively target intervention activities. We recruited 307 MSM in Gert Sibande and 298 in Ehlanzeni through respondent-driven sampling (RDS between September 2012-March 2013. RDS-adjusted HIV prevalence estimates are 28.3% (95% CI 21.1%-35.3% in Gert Sibande, and 13.7% (95% CI 9.1%-19.6% in Ehlanzeni. Prevalence is significantly higher among MSM over age 25 [57.8% (95% CI 43.1%-72.9% vs. 17.9% (95% CI 10.6%-23.9%, P<0.001 in Gert Sibande; 34.5% (95%CI 20.5%-56.0% vs. 9.1% (95% CI 4.6%-13.9%, P<0.001 in Ehlanzeni]. In Gert Sibande, prevalence is higher among self-identified gay and transgender MSM vs. other MSM [39.3% (95%CI, 28.3%-47.9%, P<0.01], inconsistent condom users [38.1% (18.1%-64.2%, P<0.05], those with a current regular male partner [35.0% (27.1%-46.4%, P<0.05], and those with lifetime experience of intimate partner violence with men [40.4%, (95%CI 28.9%-50.9%, P<0.05]. Prevalence of previous HIV testing was 65.8% (95%CI 58.8%-74.0% in Gert Sibande, and 69.3% (95%CI 61.9%-76.8% in Ehlanzeni. Regular HIV testing was uncommon [(34.6%, (95%CI 27.9%-41.4% in Gert Sibande; 31.0% (95%CI 24.9%-37.8% in Ehlanzeni]. Among HIV-positive participants, few knew their status (28.1% in Gert Sibande and 14.5% in Ehlanzeni, or were appropriately linked to care (18.2% and 11.3%, respectively, or taking antiretroviral therapy (13.6% and 9.6% respectively. MPMS results demonstrate the importance of implementing interventions for MSM to increase consistent condom use, regular HIV testing, and

Primal scene derivatives in the work of Yukio Mishima: the primal scene fantasy.

Science.gov (United States)

Turco, Ronald N

2002-01-01

This article discusses the preoccupation with fire, revenge, crucifixion, and other fantasies as they relate to the primal scene. The manifestations of these fantasies are demonstrated in a work of fiction by Yukio Mishima. The Temple of the Golden Pavillion. As is the case in other writings of Mishima there is a fusion of aggressive and libidinal drives and a preoccupation with death. The primal scene is directly connected with pyromania and destructive "acting out" of fantasies. This article is timely with regard to understanding contemporary events of cultural and national destruction.

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.

Knowledge Guided Disambiguation for Large-Scale Scene Classification With Multi-Resolution CNNs

Science.gov (United States)

Wang, Limin; Guo, Sheng; Huang, Weilin; Xiong, Yuanjun; Qiao, Yu

2017-04-01

Convolutional Neural Networks (CNNs) have made remarkable progress on scene recognition, partially due to these recent large-scale scene datasets, such as the Places and Places2. Scene categories are often defined by multi-level information, including local objects, global layout, and background environment, thus leading to large intra-class variations. In addition, with the increasing number of scene categories, label ambiguity has become another crucial issue in large-scale classification. This paper focuses on large-scale scene recognition and makes two major contributions to tackle these issues. First, we propose a multi-resolution CNN architecture that captures visual content and structure at multiple levels. The multi-resolution CNNs are composed of coarse resolution CNNs and fine resolution CNNs, which are complementary to each other. Second, we design two knowledge guided disambiguation techniques to deal with the problem of label ambiguity. (i) We exploit the knowledge from the confusion matrix computed on validation data to merge ambiguous classes into a super category. (ii) We utilize the knowledge of extra networks to produce a soft label for each image. Then the super categories or soft labels are employed to guide CNN training on the Places2. We conduct extensive experiments on three large-scale image datasets (ImageNet, Places, and Places2), demonstrating the effectiveness of our approach. Furthermore, our method takes part in two major scene recognition challenges, and achieves the second place at the Places2 challenge in ILSVRC 2015, and the first place at the LSUN challenge in CVPR 2016. Finally, we directly test the learned representations on other scene benchmarks, and obtain the new state-of-the-art results on the MIT Indoor67 (86.7\\%) and SUN397 (72.0\\%). We release the code and models at~\\url{https://github.com/wanglimin/MRCNN-Scene-Recognition}.

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.

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.

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.

iTunes song-gifting is a low-cost, efficient recruitment tool to engage high-risk MSM in internet research.

Science.gov (United States)

Holland, Christine M; Ritchie, Natalie D; Du Bois, Steve N

2015-10-01

This brief report describes methodology and results of a novel, efficient, and low-cost recruitment tool to engage high-risk MSM in online research. We developed an incentivization protocol using iTunes song-gifting to encourage participation of high-risk MSM in an Internet-based survey of HIV status, childhood sexual abuse, and adult behavior and functioning. Our recruitment methodology yielded 489 participants in 4.5 months at a total incentive cost of $1.43USD per participant. The sample comprised a critically high-risk group of MSM, including 71.0 % who reported recent condomless anal intercourse. We offer a "how-to" guide to aid future investigators in using iTunes song-gifting incentives.

The roles of scene gist and spatial dependency among objects in the semantic guidance of attention in real-world scenes.

Science.gov (United States)

Wu, Chia-Chien; Wang, Hsueh-Cheng; Pomplun, Marc

2014-12-01

A previous study (Vision Research 51 (2011) 1192-1205) found evidence for semantic guidance of visual attention during the inspection of real-world scenes, i.e., an influence of semantic relationships among scene objects on overt shifts of attention. In particular, the results revealed an observer bias toward gaze transitions between semantically similar objects. However, this effect is not necessarily indicative of semantic processing of individual objects but may be mediated by knowledge of the scene gist, which does not require object recognition, or by known spatial dependency among objects. To examine the mechanisms underlying semantic guidance, in the present study, participants were asked to view a series of displays with the scene gist excluded and spatial dependency varied. Our results show that spatial dependency among objects seems to be sufficient to induce semantic guidance. Scene gist, on the other hand, does not seem to affect how observers use semantic information to guide attention while viewing natural scenes. Extracting semantic information mainly based on spatial dependency may be an efficient strategy of the visual system that only adds little cognitive load to the viewing task. Copyright © 2014 Elsevier Ltd. All rights reserved.

The Relationship Between Online Social Network Use, Sexual Risk Behaviors, and HIV Sero-Status Among a Sample of Predominately African American and Latino Men Who have Sex with Men (MSM) Social Media Users.

Science.gov (United States)

Chiu, ChingChe J; Young, Sean D

2015-06-01

Social networking technologies have emerged as potential platforms to reach HIV(+) MSM in HIV interventions. This study sought to compare use of online social networking sites (SNSs) and sexual risk behaviors between HIV(+) and HIV(-) individuals among a sample of predominately African American and Latino SNS-using MSM. A total of 112 MSM Facebook users were recruited online and offline and completed an online survey. We performed regression models to assess the association between HIV status, SNS use, and sexual risk behaviors. After adjusting for age, race, and employment status, being HIV positive was significantly associated with a greater number of sexual partners (ARR = 2.84, p = 0.0017) and lower comfort levels of discussing HIV/STI status on SNSs (AOR: 0.23, p = 0.011). Findings suggest that HIV status is associated with sexual risk behaviors and SNS use among SNS-using MSM. We discuss the implications for online HIV prevention.

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'.

Contextualizing willingness to participate: recommendations for engagement, recruitment & enrolment of Kenyan MSM in future HIV prevention trials

Directory of Open Access Journals (Sweden)

Monika Doshi

2017-05-01

Full Text Available Abstract Background The HIV epidemic among men who have sex with men (MSM continues to expand globally. The addition of an efficacious, prophylactic vaccine to combination prevention offers immense hope, particularly in low- and middle- income countries which bear the greatest global impact. However, in these settings, there is a paucity of vaccine preparedness studies that specifically pertain to MSM. Our study is the first vaccine preparedness study among MSM and female sex workers (FSWs in Kenya. In this paper, we explore willingness of Kenyan MSM to participate in HIV vaccine efficacy trials. In addition to individual and socio-cultural motivators and barriers that influence willingness to participate (WTP, we explore the associations or linkages that participants draw between their experiences with or knowledge of medical research both generally and within the context of HIV/AIDS, their perceptions of a future HIV vaccine and their willingness to participate in HIV vaccine trials. Methods Using a social network-based approach, we employed snowball sampling to recruit MSM into the study from Kisumu, Mombasa, and Nairobi. A field team consisting of seven community researchers conducted in-depth interviews with a total of 70 study participants. A coding scheme for transcribed and translated data was developed and the data was then analysed thematically. Results Most participants felt that an HIV vaccine would bring a number of benefits to self, as well as to MSM communities, including quelling personal fears related to HIV acquisition and reducing/eliminating stigma and discrimination shouldered by their community. Willingness to participate in HIV vaccine efficacy trials was highly motivated by various forms of altruism. Specific researcher responsibilities centred on safe-guarding the rights and well-being of participants were also found to govern WTP, as were reflections on the acceptability of a future preventive HIV vaccine. Conclusion

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.; Holland, Claire E.; Katterl, Rachel; Rosman, Lori; Baral, Stefan D.

2017-01-01

Background 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. Methods and findings 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. Conclusions 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. PMID:29190642

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.

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.

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.

MSM enhances GH signaling via the Jak2/STAT5b pathway in osteoblast-like cells and osteoblast differentiation through the activation of STAT5b in MSCs.

Directory of Open Access Journals (Sweden)

Youn Hee Joung

Full Text Available Methylsulfonylmethane (MSM is a naturally occurring sulfur compound with well-known anti-oxidant properties and anti-inflammatory activities. But, its effects on bone are unknown. Growth hormone (GH is regulator of bone growth and bone metabolism. GH activates several signaling pathways such as the Janus kinase (Jak/signal transducers and activators of transcription (STAT pathway, thereby regulating expression of genes including insulin-like growth factor (IGF-1. GH exerts effects both directly and via IGF-1, which signals by activating the IGF-1 receptor (IGF-1R. In this study, we investigated the effects of MSM on the GH signaling via the Jak/STAT pathway in osteoblasts and the differentiation of primary bone marrow mesenchymal stem cells (MSCs. MSM was not toxic to osteoblastic cells and MSCs. MSM increased the expression of GH-related proteins including IGF-1R, p-IGF-1R, STAT5b, p-STAT5b, and Jak2 in osteoblastic cells and MSCs. MSM increased IGF-1R and GHR mRNA expression in osteoblastic cells. The expression of MSM-induced IGF-1R and GHR was inhibited by AG490, a Jak2 kinase inhibitor. MSM induced binding of STAT5 to the IGF-1R and increased IGF-1 and IGF-1R promoter activities. Analysis of cell extracts by immunoprecipitation and Western blot showed that MSM enhanced GH-induced activation of Jak2/STAT5b. We found that MSM and GH, separately or in combination, activated GH signaling via the Jak2/STAT5b pathway in UMR-106 cells. Using siRNA analysis, we found that STAT5b plays an essential role in GH signaling activation in C3H10T1/2 cells. Osteogenic marker genes (ALP, ON, OCN, BSP, OSX, and Runx2 were activated by MSM, and siRNA-mediated STAT5b knockdown inhibited MSM-induced expression of osteogenic markers. Furthermore, MSM increased ALP activity and the mineralization of MSCs. Taken together, these results indicated that MSM can promote osteogenic differentiation of MSCs through activation of STAT5b.

ViCoMo : visual context modeling for scene understanding in video surveillance

NARCIS (Netherlands)

Creusen, I.M.; Javanbakhti, S.; Loomans, M.J.H.; Hazelhoff, L.; Roubtsova, N.S.; Zinger, S.; With, de P.H.N.

2013-01-01

The use of contextual information can significantly aid scene understanding of surveillance video. Just detecting people and tracking them does not provide sufficient information to detect situations that require operator attention. We propose a proof-of-concept system that uses several sources of

ZnSe MSM photodetectors prepared on GaAs and ZnSe substrates

International Nuclear Information System (INIS)

Lin, T.K.; Chang, S.J.; Su, Y.K.; Chiou, Y.Z.; Wang, C.K.; Chang, S.P.; Chang, C.M.; Tang, J.J.; Huang, B.R.

2005-01-01

Homoepitaxial and heteroepitaxial ZnSe metal-semiconductor-metal (MSM) photodetectors were both fabricated and characterized. It was found that homoepitaxial ZnSe MSM photodetector could provide us smaller dark current and large photocurrent. With an incident wavelength of 448 nm, it was found that the maximum responsivities for the homoepitaxial and heteroepitaxial ZnSe photodetectors were 0.128 and 0.045 A/W, which corresponds to a quantum efficiency of 36 and 12%, respectively. Furthermore, it was found that we achieved the minimum noise equivalent power (NEP) of 7.6 x 10 -13 W and the maximum normalized detectivity (D *) of 9.3 x 10 11 cm Hz 0.5 W -1 from our homoepitaxial ZnSe photodetector. In contrast, NEP and D * of the heteroepitaxial ZnSe photodetector were 2.9 x 10 -12 W and 2.44 x 10 11 cm Hz 0.5 W -1 , respectively

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

Association of human papillomavirus infection and abnormal anal cytology among HIV-infected MSM in Beijing, China.

Directory of Open Access Journals (Sweden)

Yu Yang

Full Text Available 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.

Mapping Invasive Tamarisk (Tamarix: A Comparison of Single-Scene and Time-Series Analyses of Remotely Sensed Data

Directory of Open Access Journals (Sweden)

Paul H. Evangelista

2009-08-01

Full Text Available In this study, we tested the Maximum Entropy model (Maxent for its application and performance in remotely sensing invasive Tamarix sp. Six Landsat 7 ETM+ satellite scenes and a suite of vegetation indices at different times of the growing season were selected for our study area along the Arkansas River in Colorado. Satellite scenes were selected for April, May, June, August, September, and October and tested in single-scene and time-series analyses. The best model was a time-series analysis fit with all spectral variables, which had an AUC = 0.96, overall accuracy = 0.90, and Kappa = 0.79. The top predictor variables were June tasselled cap wetness, September tasselled cap wetness, and October band 3. A second time-series analysis, where the variables that were highly correlated and demonstrated low predictive strengths were removed, was the second best model. The third best model was the October single-scene analysis. Our results may prove to be an effective approach for mapping Tamarix sp., which has been a challenge for resource managers. Of equal importance is the positive performance of the Maxent model in handling remotely sensed datasets.

Presentation of 3D Scenes Through Video Example.

Science.gov (United States)

Baldacci, Andrea; Ganovelli, Fabio; Corsini, Massimiliano; Scopigno, Roberto

2017-09-01

Using synthetic videos to present a 3D scene is a common requirement for architects, designers, engineers or Cultural Heritage professionals however it is usually time consuming and, in order to obtain high quality results, the support of a film maker/computer animation expert is necessary. We introduce an alternative approach that takes the 3D scene of interest and an example video as input, and automatically produces a video of the input scene that resembles the given video example. In other words, our algorithm allows the user to "replicate" an existing video, on a different 3D scene. We build on the intuition that a video sequence of a static environment is strongly characterized by its optical flow, or, in other words, that two videos are similar if their optical flows are similar. We therefore recast the problem as producing a video of the input scene whose optical flow is similar to the optical flow of the input video. Our intuition is supported by a user-study specifically designed to verify this statement. We have successfully tested our approach on several scenes and input videos, some of which are reported in the accompanying material of this paper.

MSM, an Efficient Workflow for Metabolite Identification Using Hybrid Linear Ion Trap Orbitrap Mass Spectrometer

Science.gov (United States)

Cho, Robert; Huang, Yingying; Schwartz, Jae C.; Chen, Yan; Carlson, Timothy J.; Ma, Ji

2012-05-01

Identification of drug metabolites can often yield important information regarding clearance mechanism, pharmacologic activity, or toxicity for drug candidate molecules. Additionally, the identification of metabolites can provide beneficial structure-activity insight to help guide lead optimization efforts towards molecules with optimal metabolic profiles. There are challenges associated with detecting and identifying metabolites in the presence of complex biological matrices, and new LC-MS technologies have been developed to meet these challenges. In this report, we describe the development of an experimental approach that applies unique features of the hybrid linear ion trap Orbitrap mass spectrometer to streamline in vitro and in vivo metabolite identification experiments. The approach, referred to as MSM, utilizes multiple collision cells, dissociation methods, mass analyzers, and detectors. With multiple scan types and different dissociation modes built into one experimental method, along with flexible post-acquisition analysis options, the MSM workflow offers an attractive option to fast and reliable identification of metabolites in different kinds of in vitro and in vivo samples. The MSM workflow was successfully applied to metabolite identification analysis of verapamil in both in vitro rat hepatocyte incubations and in vivo rat bile samples.

47 CFR 80.1127 - On-scene communications.

Science.gov (United States)

2010-10-01

....1127 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES STATIONS IN THE MARITIME SERVICES Global Maritime Distress and Safety System (GMDSS) Operating Procedures for Distress and Safety Communications § 80.1127 On-scene communications. (a) On-scene communications...

Alcohol Use and HIV Risk Within Social Networks of MSM Sex Workers in the Dominican Republic.

Science.gov (United States)

Tan, Diane; Holloway, Ian W; Gildner, Jennifer; Jauregui, Juan C; Garcia Alvarez, Rafael; Guilamo-Ramos, Vincent

2017-11-01

To examine how alcohol-related HIV risk behaviors within MSM sex workers' social networks (SN) may be associated with individual risk behaviors, respondent-driven and venue-based sampling were used to collect demographic, behavioral and SN characteristics among MSM sex workers in Santo Domingo and Boca Chica (N = 220). The majority of participants reported problem drinking (71.0%) or alcohol use at their last sexual encounter (71.4%). Self-reported problem drinking was associated with SN characteristics (at least one member who recently got drunk aOR = 7.5, no religious/spiritual adviser aOR = 3.0, non-sexual network density aOR = 0.9), while self-reported alcohol use at last sex was associated with individual (drug use at last sex aOR = 4.4) and SN characteristics (at least one member with previous HIV/STI testing aOR = 4.7). Dominican MSM sex workers reported high alcohol use, which may increase their risk for HIV. A better understanding of SN factors associated with individual risk behaviors can help guide appropriate intervention development.

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

2018-07-01

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.

Boys must be men, and men must have sex with women: a qualitative CBPR study to explore sexual risk among African American, Latino, and White gay men and MSM.

Science.gov (United States)

Rhodes, Scott D; Hergenrather, Kenneth C; Vissman, Aaron T; Stowers, Jason; Davis, A Bernard; Hannah, Anthony; Alonzo, Jorge; Marsiglia, Flavio F

2011-03-01

Men who have sex with men (MSM) continue to be disproportionately affected by HIV and sexually transmitted diseases. This study was designed to explore sexual risk among MSM using community-based participatory research (CBPR). An academic-community partnership conducted nine focus groups with 88 MSM. Participants self-identified as African American/Black (n=28), Hispanic/Latino (n=33), White (n=21), and biracial/ethnic (n=6). The mean age was 27 years (range=18-60 years). Grounded theory was used. Twelve themes related to HIV risk emerged, including low knowledge of HIV and sexually transmitted diseases, particularly among Latino MSM and MSM who use the Internet for sexual networking; stereotyping of African American MSM as sexually "dominant" and Latino MSM as less likely to be HIV infected; and the eroticization of "barebacking." Twelve intervention approaches also were identified, including developing culturally congruent programming using community-identified assets, harnessing social media used by informal networks of MSM, and promoting protection within the context of intimate relationships. A community forum was held to develop recommendations and move these themes to action. © The Author(s) 2011

The occipital place area represents the local elements of scenes.

Science.gov (United States)

Kamps, Frederik S; Julian, Joshua B; Kubilius, Jonas; Kanwisher, Nancy; Dilks, Daniel D

2016-05-15

Neuroimaging studies have identified three scene-selective regions in human cortex: parahippocampal place area (PPA), retrosplenial complex (RSC), and occipital place area (OPA). However, precisely what scene information each region represents is not clear, especially for the least studied, more posterior OPA. Here we hypothesized that OPA represents local elements of scenes within two independent, yet complementary scene descriptors: spatial boundary (i.e., the layout of external surfaces) and scene content (e.g., internal objects). If OPA processes the local elements of spatial boundary information, then it should respond to these local elements (e.g., walls) themselves, regardless of their spatial arrangement. Indeed, we found that OPA, but not PPA or RSC, responded similarly to images of intact rooms and these same rooms in which the surfaces were fractured and rearranged, disrupting the spatial boundary. Next, if OPA represents the local elements of scene content information, then it should respond more when more such local elements (e.g., furniture) are present. Indeed, we found that OPA, but not PPA or RSC, responded more to multiple than single pieces of furniture. Taken together, these findings reveal that OPA analyzes local scene elements - both in spatial boundary and scene content representation - while PPA and RSC represent global scene properties. Copyright © 2016 Elsevier Inc. All rights reserved.

Fundamental remote sensing science research program. Part 1: Scene radiation and atmospheric effects characterization project

Science.gov (United States)

Murphy, R. E.; Deering, D. W.

1984-01-01

Brief articles summarizing the status of research in the scene radiation and atmospheric effect characterization (SRAEC) project are presented. Research conducted within the SRAEC program is focused on the development of empirical characterizations and mathematical process models which relate the electromagnetic energy reflected or emitted from a scene to the biophysical parameters of interest.

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.

Accumulating and remembering the details of neutral and emotional natural scenes.

Science.gov (United States)

Melcher, David

2010-01-01

In contrast to our rich sensory experience with complex scenes in everyday life, the capacity of visual working memory is thought to be quite limited. Here our memory has been examined for the details of naturalistic scenes as a function of display duration, emotional valence of the scene, and delay before test. Individual differences in working memory and long-term memory for pictorial scenes were examined in experiment 1. The accumulation of memory for emotional scenes and the retention of these details in long-term memory were investigated in experiment 2. Although there were large individual differences in performance, memory for scene details generally exceeded the traditional working memory limit within a few seconds. Information about positive scenes was learned most quickly, while negative scenes showed the worst memory for details. The overall pattern of results was consistent with the idea that both short-term and long-term representations are mixed together in a medium-term 'online' memory for scenes.

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

The probability of object-scene co-occurrence influences object identification processes.

Science.gov (United States)

Sauvé, Geneviève; Harmand, Mariane; Vanni, Léa; Brodeur, Mathieu B

2017-07-01

Contextual information allows the human brain to make predictions about the identity of objects that might be seen and irregularities between an object and its background slow down perception and identification processes. Bar and colleagues modeled the mechanisms underlying this beneficial effect suggesting that the brain stocks information about the statistical regularities of object and scene co-occurrence. Their model suggests that these recurring regularities could be conceptualized along a continuum in which the probability of seeing an object within a given scene can be high (probable condition), moderate (improbable condition) or null (impossible condition). In the present experiment, we propose to disentangle the electrophysiological correlates of these context effects by directly comparing object-scene pairs found along this continuum. We recorded the event-related potentials of 30 healthy participants (18-34 years old) and analyzed their brain activity in three time windows associated with context effects. We observed anterior negativities between 250 and 500 ms after object onset for the improbable and impossible conditions (improbable more negative than impossible) compared to the probable condition as well as a parieto-occipital positivity (improbable more positive than impossible). The brain may use different processing pathways to identify objects depending on whether the probability of co-occurrence with the scene is moderate (rely more on top-down effects) or null (rely more on bottom-up influences). The posterior positivity could index error monitoring aimed to ensure that no false information is integrated into mental representations of the world.

“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

Directory of Open Access Journals (Sweden)

Sameer Kushwaha

2017-10-01

Full Text Available Abstract Background 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. Methods 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. Results 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. Conclusion 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

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.

Feature diagnosticity and task context shape activity in human scene-selective cortex.

Science.gov (United States)

Lowe, Matthew X; Gallivan, Jason P; Ferber, Susanne; Cant, Jonathan S

2016-01-15

Scenes are constructed from multiple visual features, yet previous research investigating scene processing has often focused on the contributions of single features in isolation. In the real world, features rarely exist independently of one another and likely converge to inform scene identity in unique ways. Here, we utilize fMRI and pattern classification techniques to examine the interactions between task context (i.e., attend to diagnostic global scene features; texture or layout) and high-level scene attributes (content and spatial boundary) to test the novel hypothesis that scene-selective cortex represents multiple visual features, the importance of which varies according to their diagnostic relevance across scene categories and task demands. Our results show for the first time that scene representations are driven by interactions between multiple visual features and high-level scene attributes. Specifically, univariate analysis of scene-selective cortex revealed that task context and feature diagnosticity shape activity differentially across scene categories. Examination using multivariate decoding methods revealed results consistent with univariate findings, but also evidence for an interaction between high-level scene attributes and diagnostic visual features within scene categories. Critically, these findings suggest visual feature representations are not distributed uniformly across scene categories but are shaped by task context and feature diagnosticity. Thus, we propose that scene-selective cortex constructs a flexible representation of the environment by integrating multiple diagnostically relevant visual features, the nature of which varies according to the particular scene being perceived and the goals of the observer. Copyright © 2015 Elsevier Inc. All rights reserved.

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.

Maxwellian Eye Fixation during Natural Scene Perception

Science.gov (United States)

Duchesne, Jean; Bouvier, Vincent; Guillemé, Julien; Coubard, Olivier A.

2012-01-01

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. PMID:23226987

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.

Selective scene perception deficits in a case of topographical disorientation.

Science.gov (United States)

Robin, Jessica; Lowe, Matthew X; Pishdadian, Sara; Rivest, Josée; Cant, Jonathan S; Moscovitch, Morris

2017-07-01

Topographical disorientation (TD) is a neuropsychological condition characterized by an inability to find one's way, even in familiar environments. One common contributing cause of TD is landmark agnosia, a visual recognition impairment specific to scenes and landmarks. Although many cases of TD with landmark agnosia have been documented, little is known about the perceptual mechanisms which lead to selective deficits in recognizing scenes. In the present study, we test LH, a man who exhibits TD and landmark agnosia, on measures of scene perception that require selectively attending to either the configural or surface properties of a scene. Compared to healthy controls, LH demonstrates perceptual impairments when attending to the configuration of a scene, but not when attending to its surface properties, such as the pattern of the walls or whether the ground is sand or grass. In contrast, when focusing on objects instead of scenes, LH demonstrates intact perception of both geometric and surface properties. This study demonstrates that in a case of TD and landmark agnosia, the perceptual impairments are selective to the layout of scenes, providing insight into the mechanism of landmark agnosia and scene-selective perceptual processes. Copyright © 2017 Elsevier Ltd. All rights reserved.

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.

Crime Scenes as Augmented Reality

DEFF Research Database (Denmark)

Sandvik, Kjetil

2010-01-01

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......, 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...

Evolutionary history of HIV-1 subtype B and CRF01_AE transmission clusters among men who have sex with men (MSM) in Kuala Lumpur, Malaysia.

Science.gov (United States)

Ng, Kim Tien; Ong, Lai Yee; Lim, Sin How; Takebe, Yutaka; Kamarulzaman, Adeeba; Tee, Kok Keng

2013-01-01

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.

Use of respondent driven sampling (RDS generates a very diverse sample of men who have sex with men (MSM in Buenos Aires, Argentina.

Directory of Open Access Journals (Sweden)

Alex Carballo-Diéguez

Full Text Available Prior research focusing on men who have sex with men (MSM conducted in Buenos Aires, Argentina, used convenience samples that included mainly gay identified men. To increase MSM sample representativeness, we used Respondent Driven Sampling (RDS for the first time in Argentina. Using RDS, under certain specified conditions, the observed estimates for the percentage of the population with a specific trait are asymptotically unbiased. We describe, the diversity of the recruited sample, from the point of view of sexual orientation, and contrast the different subgroups in terms of their HIV sexual risk behavior.500 MSM were recruited using RDS. Behavioral data were collected through face-to-face interviews and Web-based CASI.In contrast with prior studies, RDS generated a very diverse sample of MSM from a sexual identity perspective. Only 24.5% of participants identified as gay; 36.2% identified as bisexual, 21.9% as heterosexual, and 17.4% were grouped as "other." Gay and non-gay identified MSM differed significantly in their sexual behavior, the former having higher numbers of partners, more frequent sexual contacts and less frequency of condom use. One third of the men (gay, 3%; bisexual, 34%, heterosexual, 51%; other, 49% reported having had sex with men, women and transvestites in the two months prior to the interview. This population requires further study and, potentially, HIV prevention strategies tailored to such diversity of partnerships. Our results highlight the potential effectiveness of using RDS to reach non-gay identified MSM. They also present lessons learned in the implementation of RDS to recruit MSM concerning both the importance and limitations of formative work, the need to tailor incentives to circumstances of the less affluent potential participants, the need to prevent masking, and the challenge of assessing network size.

Factors associated with self-reported HBV vaccination among HIV-negative MSM participating in an online sexual health survey: a cross-sectional study.

Directory of Open Access Journals (Sweden)

Jonathan E Matthews

Full Text Available A substantial proportion of men who have sex with men (MSM in the United States remain unvaccinated against hepatitis B. We sought to understand which factors are associated with vaccination among HIV-negative MSM.Data were from a 2010 web-based survey of adult MSM. We calculated the prevalence of self-reported hepatitis B vaccination among 1,052 HIV-negative or HIV-untested men who knew their hepatitis B vaccination status, and used multivariate logistic regression to determine associated factors. 679 (64.5% MSM reported being vaccinated. Younger men were more likely to report being vaccinated than older men, and there was a significant interaction between age and history of hepatitis B testing. Men with at least some college education were at least 2.1 times as likely to be vaccinated as men with a high school education or less (95% CI = 1.4-3.1. Provider recommendation for vaccination (aOR = 4.2, 95% CI = 2.4-7.4 was also significantly associated with receipt of vaccination.Providers should assess sexual histories of male patients and offer those patients with male sex partners testing for hepatitis infection and vaccinate susceptible patients. There may be particular opportunities for screening and vaccination among older and more socioeconomically disadvantaged MSM.

Relation between HIV status, risky sexual behavior, and mental health in an MSM sample from three Chilean cities

Directory of Open Access Journals (Sweden)

Fabiola Gómez

2017-04-01

Full Text Available ABSTRACT Objective 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. Methods 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. Results 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. Conclusions 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.

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...... are in accordance with findings in other European outbreaks. As the general immunity to hepatitis A decreases and the outbreak potential increases, we recommend health education and hepatitis A vaccination to all MSM not living in monogamous relationships, especially if they visit gay saunas or other places...

Using 3D range cameras for crime scene documentation and legal medicine

Science.gov (United States)

Cavagnini, Gianluca; Sansoni, Giovanna; Trebeschi, Marco

2009-01-01

Crime scene documentation and legal medicine analysis are part of a very complex process which is aimed at identifying the offender starting from the collection of the evidences on the scene. This part of the investigation is very critical, since the crime scene is extremely volatile, and once it is removed, it can not be precisely created again. For this reason, the documentation process should be as complete as possible, with minimum invasiveness. The use of optical 3D imaging sensors has been considered as a possible aid to perform the documentation step, since (i) the measurement is contactless and (ii) the process required to editing and modeling the 3D data is quite similar to the reverse engineering procedures originally developed for the manufacturing field. In this paper we show the most important results obtained in the experimentation.

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.

Prevalence of HIV, STIs, and risk behaviors in a cross-sectional community- and clinic-based sample of men who have sex with men (MSM) in Lima, Peru.

Science.gov (United States)

Perez-Brumer, Amaya G; Konda, Kelika A; Salvatierra, H Javier; Segura, Eddy R; Hall, Eric R; Montano, Silvia M; Coates, Thomas J; Klausner, Jeff D; Caceres, Carlos F; Clark, Jesse L

2013-01-01

Further research is necessary to understand the factors contributing to the high prevalence of HIV/STIs among men who have sex with men (MSM) in Peru. We compared HIV/STI prevalence and risk factors between two non-probability samples of MSM, one passively enrolled from an STI clinic and the other actively enrolled from community venues surrounding the clinic in Lima, Peru. A total of 560 self-identified MSM were enrolled between May-December, 2007. 438 subjects enrolled from a municipal STI clinic and 122 subjects enrolled during community outreach visits. All participants underwent screening for HIV, syphilis, HSV-2, gonorrhoea, and chlamydia and completed a survey assessing their history of HIV/STIs, prior HIV testing, and sexual behavior. HIV prevalence was significantly higher among MSM enrolled from the clinic, with previously undiagnosed HIV identified in 9.1% compared with 2.6% of community participants. 15.4 % of all MSM screened were infected with ≥ 1 curable STI, 7.4% with early syphilis (RPR ≥ 1:16) and 5.5% with urethral gonorrhoea and/or chlamydia. No significant differences between populations were reported in prevalence of STIs, number of male sex partners, history of unprotected anal intercourse, or alcohol and/or drug use prior to sex. Exchange of sex for money or goods was reported by 33.5% of MSM enrolled from the clinic and 21.2% of MSM from the community (p = 0.01). Our data demonstrate that the prevalence of HIV and STIs, including syphilis, gonorrhoea, and chlamydia are extremely high among MSM enrolled from both clinic and community venues in urban Peru. New strategies are needed to address differences in HIV/STI epidemiology between clinic- and community-enrolled samples of MSM.

Alarming incidence of hepatitis C virus re-infection after treatment of sexually acquired acute hepatitis C virus infection in HIV-infected MSM

NARCIS (Netherlands)

Lambers, Femke A. E.; Prins, Maria; Thomas, Xiomara; Molenkamp, Richard; Kwa, David; Brinkman, Kees; van der Meer, Jan T. M.; Schinkel, Janke; Countinho, R.; Reesink, H.; van Baarle, D.; Smit, C.; Gras, L.; van der Veldt, W.

2011-01-01

Recent data indicate that seroprevalence of sexually transmitted hepatitis C virus (HCV) infection among MSM is stabilizing in Amsterdam. However, little is known about the incidence of HCV re-infection in MSM who have cleared their HCV infection. We, therefore, studied the incidence of re-infection

Political conservatism predicts asymmetries in emotional scene memory.

Science.gov (United States)

Mills, Mark; Gonzalez, Frank J; Giuseffi, Karl; Sievert, Benjamin; Smith, Kevin B; Hibbing, John R; Dodd, Michael D

2016-06-01

Variation in political ideology has been linked to differences in attention to and processing of emotional stimuli, with stronger responses to negative versus positive stimuli (negativity bias) the more politically conservative one is. As memory is enhanced by attention, such findings predict that memory for negative versus positive stimuli should similarly be enhanced the more conservative one is. The present study tests this prediction by having participants study 120 positive, negative, and neutral scenes in preparation for a subsequent memory test. On the memory test, the same 120 scenes were presented along with 120 new scenes and participants were to respond whether a scene was old or new. Results on the memory test showed that negative scenes were more likely to be remembered than positive scenes, though, this was true only for political conservatives. That is, a larger negativity bias was found the more conservative one was. The effect was sizeable, explaining 45% of the variance across subjects in the effect of emotion. These findings demonstrate that the relationship between political ideology and asymmetries in emotion processing extend to memory and, furthermore, suggest that exploring the extent to which subject variation in interactions among emotion, attention, and memory is predicted by conservatism may provide new insights into theories of political ideology. Published by Elsevier B.V.

Being There: (Re)Making the Assessment Scene

Science.gov (United States)

Gallagher, Chris W.

2011-01-01

I use Burkean analysis to show how neoliberalism undermines faculty assessment expertise and underwrites testing industry expertise in the current assessment scene. Contending that we cannot extricate ourselves from our limited agency in this scene until we abandon the familiar "stakeholder" theory of power, I propose a rewriting of the…

[Perception of objects and scenes in age-related macular degeneration].

Science.gov (United States)

Tran, T H C; Boucart, M

2012-01-01

Vision related quality of life questionnaires suggest that patients with AMD exhibit difficulties in finding objects and in mobility. In the natural environment, objects seldom appear in isolation. They appear in a spatial context which may obscure them in part or place obstacles in the patient's path. Furthermore, the luminance of a natural scene varies as a function of the hour of the day and the light source, which can alter perception. This study aims to evaluate recognition of objects and natural scenes by patients with AMD, by using photographs of such scenes. Studies demonstrate that AMD patients are able to categorize scenes as nature scenes or urban scenes and to discriminate indoor from outdoor scenes with a high degree of precision. They detect objects better in isolation, in color, or against a white background than in their natural contexts. These patients encounter more difficulties than normally sighted individuals in detecting objects in a low-contrast, black-and-white scene. These results may have implications for rehabilitation, for layout of texts and magazines for the reading-impaired and for the rearrangement of the spatial environment of older AMD patients in order to facilitate mobility, finding objects and reducing the risk of falls. Copyright © 2011 Elsevier Masson SAS. All rights reserved.

Motives and barriers to safer sex and regular STI testing among MSM soon after HIV diagnosis.

Science.gov (United States)

Heijman, Titia; Zuure, Freke; Stolte, Ineke; Davidovich, Udi

2017-03-07

Understanding why some recently with HIV diagnosed men who have sex with men (MSM) choose for safer sex and regular STI testing, whereas others do not, is important for the development of interventions that aim to improve the sexual health of those newly infected. To gain insight into motives and barriers to condom use and regular STI testing among MSM soon after HIV diagnosis, 30 HIV-positive MSM participated in semi-structured qualitative interviews on sexual health behaviours in the first year after HIV diagnosis. Typical barriers to condom use soon after diagnosis were emotions such as anger, relief, and feelings of vulnerability. Additional barriers were related to pre-diagnosis patterns of sexual-social behaviour that were difficult to change, communication difficulties, and substance use. Barriers to STI testing revolved around perceptions of low STI risk, faulty beliefs, and burdensome testing procedures. The great diversity of motives and barriers to condom use and STI testing creates a challenge to accommodate newly infected men with information, motivation, and communication skills to match their personal needs. An adaptive, tailored intervention can be a promising tool of support.

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.

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.

A Knowledge Base for Automatic Feature Recognition from Point Clouds in an Urban Scene

Directory of Open Access Journals (Sweden)

Xu-Feng Xing

2018-01-01

Full Text Available LiDAR technology can provide very detailed and highly accurate geospatial information on an urban scene for the creation of Virtual Geographic Environments (VGEs for different applications. However, automatic 3D modeling and feature recognition from LiDAR point clouds are very complex tasks. This becomes even more complex when the data is incomplete (occlusion problem or uncertain. In this paper, we propose to build a knowledge base comprising of ontology and semantic rules aiming at automatic feature recognition from point clouds in support of 3D modeling. First, several modules for ontology are defined from different perspectives to describe an urban scene. For instance, the spatial relations module allows the formalized representation of possible topological relations extracted from point clouds. Then, a knowledge base is proposed that contains different concepts, their properties and their relations, together with constraints and semantic rules. Then, instances and their specific relations form an urban scene and are added to the knowledge base as facts. Based on the knowledge and semantic rules, a reasoning process is carried out to extract semantic features of the objects and their components in the urban scene. Finally, several experiments are presented to show the validity of our approach to recognize different semantic features of buildings from LiDAR point clouds.

Construction and Optimization of Three-Dimensional Disaster Scenes within Mobile Virtual Reality

Directory of Open Access Journals (Sweden)

Ya Hu

2018-06-01

Full Text Available Because mobile virtual reality (VR is both mobile and immersive, three-dimensional (3D visualizations of disaster scenes based in mobile VR enable users to perceive and recognize disaster environments faster and better than is possible with other methods. To achieve immersion and prevent users from feeling dizzy, such visualizations require a high scene-rendering frame rate. However, the existing related visualization work cannot provide a sufficient solution for this purpose. This study focuses on the construction and optimization of a 3D disaster scene in order to satisfy the high frame-rate requirements for the rendering of 3D disaster scenes in mobile VR. First, the design of a plugin-free browser/server (B/S architecture for 3D disaster scene construction and visualization based in mobile VR is presented. Second, certain key technologies for scene optimization are discussed, including diverse modes of scene data representation, representation optimization of mobile scenes, and adaptive scheduling of mobile scenes. By means of these technologies, smartphones with various performance levels can achieve higher scene-rendering frame rates and improved visual quality. Finally, using a flood disaster as an example, a plugin-free prototype system was developed, and experiments were conducted. The experimental results demonstrate that a 3D disaster scene constructed via the methods addressed in this study has a sufficiently high scene-rendering frame rate to satisfy the requirements for rendering a 3D disaster scene in mobile VR.

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.

The neural bases of spatial frequency processing during scene perception

Science.gov (United States)

Kauffmann, Louise; Ramanoël, Stephen; Peyrin, Carole

2014-01-01

Theories on visual perception agree that scenes are processed in terms of spatial frequencies. Low spatial frequencies (LSF) carry coarse information whereas high spatial frequencies (HSF) carry fine details of the scene. However, how and where spatial frequencies are processed within the brain remain unresolved questions. The present review addresses these issues and aims to identify the cerebral regions differentially involved in low and high spatial frequency processing, and to clarify their attributes during scene perception. Results from a number of behavioral and neuroimaging studies suggest that spatial frequency processing is lateralized in both hemispheres, with the right and left hemispheres predominantly involved in the categorization of LSF and HSF scenes, respectively. There is also evidence that spatial frequency processing is retinotopically mapped in the visual cortex. HSF scenes (as opposed to LSF) activate occipital areas in relation to foveal representations, while categorization of LSF scenes (as opposed to HSF) activates occipital areas in relation to more peripheral representations. Concomitantly, a number of studies have demonstrated that LSF information may reach high-order areas rapidly, allowing an initial coarse parsing of the visual scene, which could then be sent back through feedback into the occipito-temporal cortex to guide finer HSF-based analysis. Finally, the review addresses spatial frequency processing within scene-selective regions areas of the occipito-temporal cortex. PMID:24847226

Detection of chromatic and luminance distortions in natural scenes.

Science.gov (United States)

Jennings, Ben J; Wang, Karen; Menzies, Samantha; Kingdom, Frederick A A

2015-09-01

A number of studies have measured visual thresholds for detecting spatial distortions applied to images of natural scenes. In one study, Bex [J. Vis.10(2), 1 (2010)10.1167/10.2.231534-7362] measured sensitivity to sinusoidal spatial modulations of image scale. Here, we measure sensitivity to sinusoidal scale distortions applied to the chromatic, luminance, or both layers of natural scene images. We first established that sensitivity does not depend on whether the undistorted comparison image was of the same or of a different scene. Next, we found that, when the luminance but not chromatic layer was distorted, performance was the same regardless of whether the chromatic layer was present, absent, or phase-scrambled; in other words, the chromatic layer, in whatever form, did not affect sensitivity to the luminance layer distortion. However, when the chromatic layer was distorted, sensitivity was higher when the luminance layer was intact compared to when absent or phase-scrambled. These detection threshold results complement the appearance of periodic distortions of the image scale: when the luminance layer is distorted visibly, the scene appears distorted, but when the chromatic layer is distorted visibly, there is little apparent scene distortion. We conclude that (a) observers have a built-in sense of how a normal image of a natural scene should appear, and (b) the detection of distortion in, as well as the apparent distortion of, natural scene images is mediated predominantly by the luminance layer and not chromatic layer.

Sexual identities and sexual health within the Celtic nations: An exploratory study of men who have sex with men recruited through social media.

Science.gov (United States)

McAloney-Kocaman, Kareena; Lorimer, Karen; Flowers, Paul; Davis, Mark; Knussen, Christina; Frankis, Jamie

2016-01-01

Associations of sexual identity with a range of sexual and sexual health behaviours were investigated amongst men who have sex with men (MSM). Data from 1816 MSM recruited from 4 Celtic nations (Scotland, Wales, Northern Ireland and the Republic of Ireland) were collected via a cross-sectional online survey advertised via social media. About 18.3% were non-gay identified MSM (NGI-MSM). In the last year, 30% of NGI-MSM reported high-risk unprotected anal intercourse and 45% reported never having had an sexually transmitted infection (STI) test. When compared to MSM who were gay identified (GI-MSM), NGI-MSM were more likely to be older, have a female partner, fewer sex partners, fewer anal sex partners, STI diagnoses and less likely to be HIV positive, more likely to never use the gay scene and be geographically further from a gay venue. NGI-MSM were also less likely to report STI and HIV testing behaviours. The findings highlight variations in risk by sexual identities, and unmet sexual health needs amongst NGI-MSM across Celtic nations. Innovative research is required regarding the utility of social media for reaching populations of MSM and developing interventions which target the heterogeneity of MSM and their specific sexual health needs.

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.

Evolutionary History of HIV-1 Subtype B and CRF01_AE Transmission Clusters among Men Who Have Sex with Men (MSM) in Kuala Lumpur, Malaysia

Science.gov (United States)

Ng, Kim Tien; Ong, Lai Yee; Lim, Sin How; Takebe, Yutaka; Kamarulzaman, Adeeba; Tee, Kok Keng

2013-01-01

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. PMID:23840653

Visual search for changes in scenes creates long-term, incidental memory traces.

Science.gov (United States)

Utochkin, Igor S; Wolfe, Jeremy M

2018-05-01

Humans are very good at remembering large numbers of scenes over substantial periods of time. But how good are they at remembering changes to scenes? In this study, we tested scene memory and change detection two weeks after initial scene learning. In Experiments 1-3, scenes were learned incidentally during visual search for change. In Experiment 4, observers explicitly memorized scenes. At test, after two weeks observers were asked to discriminate old from new scenes, to recall a change that they had detected in the study phase, or to detect a newly introduced change in the memorization experiment. Next, they performed a change detection task, usually looking for the same change as in the study period. Scene recognition memory was found to be similar in all experiments, regardless of the study task. In Experiment 1, more difficult change detection produced better scene memory. Experiments 2 and 3 supported a "depth-of-processing" account for the effects of initial search and change detection on incidental memory for scenes. Of most interest, change detection was faster during the test phase than during the study phase, even when the observer had no explicit memory of having found that change previously. This result was replicated in two of our three change detection experiments. We conclude that scenes can be encoded incidentally as well as explicitly and that changes in those scenes can leave measurable traces even if they are not explicitly recalled.

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

of the lighting environment. This enables pixelwise comparison of photographs of the real scene with renderings of the digital version of the scene. Such quantitative evaluation is useful for verifying acquired material appearance and reconstructed surface geometry, which is an important aspect of digital content......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...

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

No evidence for a protective effect of naturally induced HPV antibodies on subsequent anogenital 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.; Coutinho, Roel A.; van Eeden, Arne; van Rooijen, Martijn S.; Meijer, Chris J. L. M.; Schim van der Loeff, Maarten F.

2014-01-01

To assess whether HPV serum antibodies detected after natural infection protect against subsequent anal or penile infection with the same HPV type 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

Two Distinct Scene-Processing Networks Connecting Vision and Memory.

Science.gov (United States)

Baldassano, Christopher; Esteva, Andre; Fei-Fei, Li; Beck, Diane M

2016-01-01

A number of regions in the human brain are known to be involved in processing natural scenes, but the field has lacked a unifying framework for understanding how these different regions are organized and interact. We provide evidence from functional connectivity and meta-analyses for a new organizational principle, in which scene processing relies upon two distinct networks that split the classically defined parahippocampal place area (PPA). The first network of strongly connected regions consists of the occipital place area/transverse occipital sulcus and posterior PPA, which contain retinotopic maps and are not strongly coupled to the hippocampus at rest. The second network consists of the caudal inferior parietal lobule, retrosplenial complex, and anterior PPA, which connect to the hippocampus (especially anterior hippocampus), and are implicated in both visual and nonvisual tasks, including episodic memory and navigation. We propose that these two distinct networks capture the primary functional division among scene-processing regions, between those that process visual features from the current view of a scene and those that connect information from a current scene view with a much broader temporal and spatial context. This new framework for understanding the neural substrates of scene-processing bridges results from many lines of research, and makes specific functional predictions.

Cognitive organization of roadway scenes : an empirical study.

NARCIS (Netherlands)

Gundy, C.M.

1995-01-01

This report describes six studies investigating the cognitive organization of roadway scenes. These scenes were represented by still photographs taken on a number of roads outside of built-up areas. Seventy-eight drivers, stratified by age and sex to simulate the Dutch driving population,

A view not to be missed: Salient scene content interferes with cognitive restoration

Science.gov (United States)

Van der Jagt, Alexander P. N.; Craig, Tony; Brewer, Mark J.; Pearson, David G.

2017-01-01

Attention Restoration Theory (ART) states that built scenes place greater load on attentional resources than natural scenes. This is explained in terms of "hard" and "soft" fascination of built and natural scenes. Given a lack of direct empirical evidence for this assumption we propose that perceptual saliency of scene content can function as an empirically derived indicator of fascination. Saliency levels were established by measuring speed of scene category detection using a Go/No-Go detection paradigm. Experiment 1 shows that built scenes are more salient than natural scenes. Experiment 2 replicates these findings using greyscale images, ruling out a colour-based response strategy, and additionally shows that built objects in natural scenes affect saliency to a greater extent than the reverse. Experiment 3 demonstrates that the saliency of scene content is directly linked to cognitive restoration using an established restoration paradigm. Overall, these findings demonstrate an important link between the saliency of scene content and related cognitive restoration. PMID:28723975

A view not to be missed: Salient scene content interferes with cognitive restoration.

Directory of Open Access Journals (Sweden)

Alexander P N Van der Jagt

Full Text Available Attention Restoration Theory (ART states that built scenes place greater load on attentional resources than natural scenes. This is explained in terms of "hard" and "soft" fascination of built and natural scenes. Given a lack of direct empirical evidence for this assumption we propose that perceptual saliency of scene content can function as an empirically derived indicator of fascination. Saliency levels were established by measuring speed of scene category detection using a Go/No-Go detection paradigm. Experiment 1 shows that built scenes are more salient than natural scenes. Experiment 2 replicates these findings using greyscale images, ruling out a colour-based response strategy, and additionally shows that built objects in natural scenes affect saliency to a greater extent than the reverse. Experiment 3 demonstrates that the saliency of scene content is directly linked to cognitive restoration using an established restoration paradigm. Overall, these findings demonstrate an important link between the saliency of scene content and related cognitive restoration.

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.

Application of the Modified Source Multiplication (MSM) Technique to Subcritical Reactivity Worth Measurements in Thermal and Fast Reactor Systems

International Nuclear Information System (INIS)

Blaise, P.; Fougeras, Ph.; Mellier, F.

2011-01-01

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. (authors)

Who Will Use Pre-Exposure Prophylaxis (PrEP) and Why?: Understanding PrEP Awareness and Acceptability amongst Men Who Have Sex with Men in the UK – A Mixed Methods Study

Science.gov (United States)

Frankis, Jamie; Young, Ingrid; Flowers, Paul; McDaid, Lisa

2016-01-01

Background Recent clinical trials suggest that pre-exposure prophylaxis (PrEP) may reduce HIV transmission by up to 86% for men who have sex with men (MSM), whilst relatively high levels of PrEP acceptability have been reported to date. This study examines PrEP awareness amongst sub-groups of MSM communities and acceptability amongst MSM in a low prevalence region (Scotland, UK), using a mixed methods design. Methods Quantitative surveys of n = 690 MSM recruited online via social and sociosexual media were analysed using descriptive statistics and multivariate logistic regression. In addition, n = 10 in-depth qualitative interviews with MSM were analysed thematically. Results Under one third (29.7%) of MSM had heard of PrEP, with awareness related to living in large cities, degree level education, commercial gay scene use and reporting an HIV test in the last year. Just under half of participants (47.8%) were likely to use PrEP if it were available but there was no relationship between PrEP acceptability and previous PrEP awareness. Younger men (18–25 years) and those who report higher risk UAI were significantly more likely to say they would use PrEP. Qualitative data described specific PrEP scenarios, illustrating how risk, patterns of sexual practice and social relationships could affect motivation for and nature of PrEP use. Conclusion These findings suggest substantial interest PrEP amongst MSM reporting HIV risk behaviours in Scotland. Given the Proud results, there is a strong case to investigate PrEP implementation within the UK. However, it appears that disparities in awareness have already emerged along traditional indicators of inequality. Our research identifies the need for comprehensive support when PrEP is introduced, including a key online component, to ensure equity of awareness across diverse MSM communities (e.g. by geography, education, gay scene use and HIV proximity), as well as to responding to the diverse informational and sexual health

Who Will Use Pre-Exposure Prophylaxis (PrEP) and Why?: Understanding PrEP Awareness and Acceptability amongst Men Who Have Sex with Men in the UK--A Mixed Methods Study.

Science.gov (United States)

Frankis, Jamie; Young, Ingrid; Flowers, Paul; McDaid, Lisa

2016-01-01

Recent clinical trials suggest that pre-exposure prophylaxis (PrEP) may reduce HIV transmission by up to 86% for men who have sex with men (MSM), whilst relatively high levels of PrEP acceptability have been reported to date. This study examines PrEP awareness amongst sub-groups of MSM communities and acceptability amongst MSM in a low prevalence region (Scotland, UK), using a mixed methods design. Quantitative surveys of n = 690 MSM recruited online via social and sociosexual media were analysed using descriptive statistics and multivariate logistic regression. In addition, n = 10 in-depth qualitative interviews with MSM were analysed thematically. Under one third (29.7%) of MSM had heard of PrEP, with awareness related to living in large cities, degree level education, commercial gay scene use and reporting an HIV test in the last year. Just under half of participants (47.8%) were likely to use PrEP if it were available but there was no relationship between PrEP acceptability and previous PrEP awareness. Younger men (18-25 years) and those who report higher risk UAI were significantly more likely to say they would use PrEP. Qualitative data described specific PrEP scenarios, illustrating how risk, patterns of sexual practice and social relationships could affect motivation for and nature of PrEP use. These findings suggest substantial interest PrEP amongst MSM reporting HIV risk behaviours in Scotland. Given the Proud results, there is a strong case to investigate PrEP implementation within the UK. However, it appears that disparities in awareness have already emerged along traditional indicators of inequality. Our research identifies the need for comprehensive support when PrEP is introduced, including a key online component, to ensure equity of awareness across diverse MSM communities (e.g. by geography, education, gay scene use and HIV proximity), as well as to responding to the diverse informational and sexual health needs of all MSM communities.

Who Will Use Pre-Exposure Prophylaxis (PrEP and Why?: Understanding PrEP Awareness and Acceptability amongst Men Who Have Sex with Men in the UK--A Mixed Methods Study.

Directory of Open Access Journals (Sweden)

Jamie Frankis

Full Text Available Recent clinical trials suggest that pre-exposure prophylaxis (PrEP may reduce HIV transmission by up to 86% for men who have sex with men (MSM, whilst relatively high levels of PrEP acceptability have been reported to date. This study examines PrEP awareness amongst sub-groups of MSM communities and acceptability amongst MSM in a low prevalence region (Scotland, UK, using a mixed methods design.Quantitative surveys of n = 690 MSM recruited online via social and sociosexual media were analysed using descriptive statistics and multivariate logistic regression. In addition, n = 10 in-depth qualitative interviews with MSM were analysed thematically.Under one third (29.7% of MSM had heard of PrEP, with awareness related to living in large cities, degree level education, commercial gay scene use and reporting an HIV test in the last year. Just under half of participants (47.8% were likely to use PrEP if it were available but there was no relationship between PrEP acceptability and previous PrEP awareness. Younger men (18-25 years and those who report higher risk UAI were significantly more likely to say they would use PrEP. Qualitative data described specific PrEP scenarios, illustrating how risk, patterns of sexual practice and social relationships could affect motivation for and nature of PrEP use.These findings suggest substantial interest PrEP amongst MSM reporting HIV risk behaviours in Scotland. Given the Proud results, there is a strong case to investigate PrEP implementation within the UK. However, it appears that disparities in awareness have already emerged along traditional indicators of inequality. Our research identifies the need for comprehensive support when PrEP is introduced, including a key online component, to ensure equity of awareness across diverse MSM communities (e.g. by geography, education, gay scene use and HIV proximity, as well as to responding to the diverse informational and sexual health needs of all MSM communities.

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

Science.gov (United States)

Godbole, Sheela; Sane, Suvarna; Kamble, Pranil; Raj, Yujwal; Dulhani, Nisha; Venkatesh, Srinivasan; Reddy, D. C. S.; Chavan, Laxmikant; Bhattacharya, Madhulekha; Bindoria, Suchitra; Kadam, Dilip; Thakur, Savita; Narwani, Prakash; Pereira, Elmira; Paranjape, Ramesh; Risbud, Arun

2014-01-01

Background 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. Methods 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. Results 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), pbehaviour’ [AOR = 2.7, 95% CI(2.3, 3.1) pbehaviour with other men, could help in reaching this population. PMID:25211511

Performance Benefits with Scene-Linked HUD Symbology: An Attentional Phenomenon?

Science.gov (United States)

Levy, Jonathan L.; Foyle, David C.; McCann, Robert S.; Null, Cynthia H. (Technical Monitor)

1999-01-01

Previous research has shown that in a simulated flight task, navigating a path defined by ground markers while maintaining a target altitude is more accurate when an altitude indicator appears in a virtual "scenelinked" format (projected symbology moving as if it were part of the out-the-window environment) compared to the fixed-location, superimposed format found on present-day HUDs (Foyle, McCann & Shelden, 1995). One explanation of the scene-linked performance advantage is that attention can be divided between scene-linked symbology and the outside world more efficiently than between standard (fixed-position) HUD symbology and the outside world. The present study tested two alternative explanations by manipulating the location of the scene-linked HUD symbology relative to the ground path markers. Scene-linked symbology yielded better ground path-following performance than standard fixed-location superimposed symbology regardless of whether the scene-linked symbology appeared directly along the ground path or at various distances off the path. The results support the explanation that the performance benefits found with scene-linked symbology are attentional.

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.

Crime Scene Investigation.

Science.gov (United States)

Harris, Barbara; Kohlmeier, Kris; Kiel, Robert D.

Casting students in grades 5 through 12 in the roles of reporters, lawyers, and detectives at the scene of a crime, this interdisciplinary activity involves participants in the intrigue and drama of crime investigation. Using a hands-on, step-by-step approach, students work in teams to investigate a crime and solve a mystery. Through role-playing…

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.

SCEGRAM: An image database for semantic and syntactic inconsistencies in scenes.

Science.gov (United States)

Öhlschläger, Sabine; Võ, Melissa Le-Hoa

2017-10-01

Our visual environment is not random, but follows compositional rules according to what objects are usually found where. Despite the growing interest in how such semantic and syntactic rules - a scene grammar - enable effective attentional guidance and object perception, no common image database containing highly-controlled object-scene modifications has been publically available. Such a database is essential in minimizing the risk that low-level features drive high-level effects of interest, which is being discussed as possible source of controversial study results. To generate the first database of this kind - SCEGRAM - we took photographs of 62 real-world indoor scenes in six consistency conditions that contain semantic and syntactic (both mild and extreme) violations as well as their combinations. Importantly, always two scenes were paired, so that an object was semantically consistent in one scene (e.g., ketchup in kitchen) and inconsistent in the other (e.g., ketchup in bathroom). Low-level salience did not differ between object-scene conditions and was generally moderate. Additionally, SCEGRAM contains consistency ratings for every object-scene condition, as well as object-absent scenes and object-only images. Finally, a cross-validation using eye-movements replicated previous results of longer dwell times for both semantic and syntactic inconsistencies compared to consistent controls. In sum, the SCEGRAM image database is the first to contain well-controlled semantic and syntactic object-scene inconsistencies that can be used in a broad range of cognitive paradigms (e.g., verbal and pictorial priming, change detection, object identification, etc.) including paradigms addressing developmental aspects of scene grammar. SCEGRAM can be retrieved for research purposes from http://www.scenegrammarlab.com/research/scegram-database/ .

Changing scenes: memory for naturalistic events following change blindness.

Science.gov (United States)

Mäntylä, Timo; Sundström, Anna

2004-11-01

Research on scene perception indicates that viewers often fail to detect large changes to scene regions when these changes occur during a visual disruption such as a saccade or a movie cut. In two experiments, we examined whether this relative inability to detect changes would produce systematic biases in event memory. In Experiment 1, participants decided whether two successively presented images were the same or different, followed by a memory task, in which they recalled the content of the viewed scene. In Experiment 2, participants viewed a short video, in which an actor carried out a series of daily activities, and central scenes' attributes were changed during a movie cut. A high degree of change blindness was observed in both experiments, and these effects were related to scene complexity (Experiment 1) and level of retrieval support (Experiment 2). Most important, participants reported the changed, rather than the initial, event attributes following a failure in change detection. These findings suggest that attentional limitations during encoding contribute to biases in episodic memory.

Sensory substitution: the spatial updating of auditory scenes ‘mimics’ the spatial updating of visual scenes

Directory of Open Access Journals (Sweden)

Achille ePasqualotto

2016-04-01

Full Text Available Visual-to-auditory sensory substitution is used to convey visual information through audition, and it was initially created to compensate for blindness; it consists of software converting the visual images captured by a video-camera into the equivalent auditory images, or ‘soundscapes’. Here, it was used by blindfolded sighted participants to learn the spatial position of simple shapes depicted in images arranged on the floor. Very few studies have used sensory substitution to investigate spatial representation, while it has been widely used to investigate object recognition. Additionally, with sensory substitution we could study the performance of participants actively exploring the environment through audition, rather than passively localising sound sources. Blindfolded participants egocentrically learnt the position of six images by using sensory substitution and then a judgement of relative direction task (JRD was used to determine how this scene was represented. This task consists of imagining being in a given location, oriented in a given direction, and pointing towards the required image. Before performing the JRD task, participants explored a map that provided allocentric information about the scene. Although spatial exploration was egocentric, surprisingly we found that performance in the JRD task was better for allocentric perspectives. This suggests that the egocentric representation of the scene was updated. This result is in line with previous studies using visual and somatosensory scenes, thus supporting the notion that different sensory modalities produce equivalent spatial representation(s. Moreover, our results have practical implications to improve training methods with sensory substitution devices.

Influence of 3D effects on 1D aerosol retrievals in synthetic, partially clouded scenes

International Nuclear Information System (INIS)

Stap, F.A.; Hasekamp, O.P.; Emde, C.; Röckmann, T.

2016-01-01

An important challenge in aerosol remote sensing is to retrieve aerosol properties in the vicinity of clouds and in cloud contaminated scenes. Satellite based multi-wavelength, multi-angular, photo-polarimetric instruments are particularly suited for this task as they have the ability to separate scattering by aerosol and cloud particles. Simultaneous aerosol/cloud retrievals using 1D radiative transfer codes cannot account for 3D effects such as shadows, cloud induced enhancements and darkening of cloud edges. In this study we investigate what errors are introduced on the retrieved optical and micro-physical aerosol properties, when these 3D effects are neglected in retrievals where the partial cloud cover is modeled using the Independent Pixel Approximation. To this end a generic, synthetic data set of PARASOL like observations for 3D scenes with partial, liquid water cloud cover is created. It is found that in scenes with random cloud distributions (i.e. broken cloud fields) and either low cloud optical thickness or low cloud fraction, the inversion algorithm can fit the observations and retrieve optical and micro-physical aerosol properties with sufficient accuracy. In scenes with non-random cloud distributions (e.g. at the edge of a cloud field) the inversion algorithm can fit the observations, however, here the retrieved real part of the refractive indices of both modes is biased. - Highlights: • An algorithm for retrieval of both aerosol and cloud properties is presented. • Radiative transfer models of 3D, partially clouded scenes are simulated. • Errors introduced in the retrieved aerosol properties are discussed.

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.

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),…

Engagement of Gay Men and Other Men Who Have Sex with Men (MSM) in the Response to HIV: A Critical Step in Achieving an AIDS-Free Generation.

Science.gov (United States)

Stahlman, Shauna; Beyrer, Chris; Sullivan, Patrick S; Mayer, Kenneth H; Baral, Stefan D

2016-12-01

Men who have sex with men (MSM) continue to be at elevated risk for HIV acquisition and transmission secondary to biological and behavioral characteristics, social and sexual network characteristics, community environmental factors, and structural factors. HIV incidence rates remain high among MSM in both low- and high-income settings, and in both concentrated and more generalized HIV epidemic settings. While data quality tends to be poorer, the best estimates collectively suggest that MSM have up to 20 times the odds of living with HIV as compared to other reproductive aged adults across low- and middle-income countries. Recent prevention strategies to lower biological HIV transmission and acquisition risks, including the early use of antiretrovirals to decrease infectiousness for those living with HIV, and pre-exposure prophylaxis for those at significant risk of HIV acquisition, have demonstrated the potential to change the trajectory of the HIV epidemics among MSM. However, the coverage and effectiveness of these approaches is limited by structural factors including the punitive legal frameworks and institutional discrimination that contribute to limited uptake, challenges to adherence, and suboptimal health-seeking behaviors among MSM. More intensive efforts will be required to reach MSM who do not currently have access to relevant and effective prevention and treatment services or elect not to access these services given enacted and/or perceived stigma. Respect for human rights, including efforts to aggressively confront and combat the forms of stigma that are preventing us from achieving an AIDS-Free generation, are needed for all people including gay men and other MSM.

Barriers, Motivators, and Facilitators to Engagement in HIV Care Among HIV-Infected Ghanaian Men Who have Sex with Men (MSM).

Science.gov (United States)

Ogunbajo, Adedotun; Kershaw, Trace; Kushwaha, Sameer; Boakye, Francis; Wallace-Atiapah, Nii-Dromo; Nelson, LaRon E

2018-03-01

In Ghana, men who have sex with men (MSM) bear a high burden of HIV. Identifying factors that influence engagement in HIV care among HIV-infected Ghanaian MSM is critical to devising novel interventions and strengthening existing programs aimed at improving outcomes across the HIV care continuum. Consequently, we conducted an exploratory qualitative research study with 30 HIV-infected Ghanaian MSM between May 2015 and July 2015. Common barriers were fear of being seen in HIV-related health facility, financial difficulties, and health system challenges. Major motivators for engagement in care included social support, fear of mortality from HIV, and knowledge of effectiveness of HIV treatment. Key facilitators were enrollment in health insurance, prior relationship and familiarity with hospital personnel, and positive experience in healthcare setting. Our findings highlight the need for new and innovative care delivery mediums, affirming and competent healthcare providers, and increased access to health insurance.

Colour agnosia impairs the recognition of natural but not of non-natural scenes.

Science.gov (United States)

Nijboer, Tanja C W; Van Der Smagt, Maarten J; Van Zandvoort, Martine J E; De Haan, Edward H F

2007-03-01

Scene recognition can be enhanced by appropriate colour information, yet the level of visual processing at which colour exerts its effects is still unclear. It has been suggested that colour supports low-level sensory processing, while others have claimed that colour information aids semantic categorization and recognition of objects and scenes. We investigated the effect of colour on scene recognition in a case of colour agnosia, M.A.H. In a scene identification task, participants had to name images of natural or non-natural scenes in six different formats. Irrespective of scene format, M.A.H. was much slower on the natural than on the non-natural scenes. As expected, neither M.A.H. nor control participants showed any difference in performance for the non-natural scenes. However, for the natural scenes, appropriate colour facilitated scene recognition in control participants (i.e., shorter reaction times), whereas M.A.H.'s performance did not differ across formats. Our data thus support the hypothesis that the effect of colour occurs at the level of learned associations.

Using data from a behavioural survey of men who have sex with men (MSM) to estimate the number likely to present for HIV pre-exposure prophylaxis (PrEP) in Ireland, 2017.

Science.gov (United States)

Nic Lochlainn, Laura; O'Donnell, Kate; Hurley, Caroline; Lyons, Fiona; Igoe, Derval

2017-11-01

In Ireland, men who have sex with men (MSM) have increased HIV risk. Pre-exposure prophylaxis (PrEP), combined with safe sex practices, can reduce HIV acquisition. We estimated MSM numbers likely to present for PrEP by applying French PrEP criteria to Irish MSM behavioural survey data. We adjusted for survey bias, calculated proportions accessing testing services and those likely to take PrEP. We estimated 1-3% of MSM in Ireland were likely to present for PrEP.

Graphics processing unit (GPU) real-time infrared scene generation

Science.gov (United States)

Christie, Chad L.; Gouthas, Efthimios (Themie); Williams, Owen M.

2007-04-01

VIRSuite, the GPU-based suite of software tools developed at DSTO for real-time infrared scene generation, is described. The tools include the painting of scene objects with radiometrically-associated colours, translucent object generation, polar plot validation and versatile scene generation. Special features include radiometric scaling within the GPU and the presence of zoom anti-aliasing at the core of VIRSuite. Extension of the zoom anti-aliasing construct to cover target embedding and the treatment of translucent objects is described.

Semantic guidance of eye movements in real-world scenes

OpenAIRE

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

2011-01-01

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 movemen...

[Study on HIV prevention related knowledge-motivation-psychological model in men who have sex with men, based on a structural equation model].

Science.gov (United States)

Jiang, Y; Dou, Y L; Cai, A J; Zhang, Z; Tian, T; Dai, J H; Huang, A L

2016-02-01

Knowledge-motivation-psychological model was set up and tested through structural equation model to provide evidence on HIV prevention related strategy in Men who have Sex with Men (MSM). Snowball sampling method was used to recruit a total of 550 MSM volunteers from two MSM Non-Governmental Organizations in Urumqi, Xinjiang province. HIV prevention related information on MSM was collected through a questionnaire survey. A total of 477 volunteers showed with complete information. HIV prevention related Knowledge-motivation-psychological model was built under related experience and literature. Relations between knowledge, motivation and psychological was studied, using a ' structural equation model' with data from the fitting questionnaires and modification of the model. Structural equation model presented good fitting results. After revising the fitting index: RMSEA was 0.035, NFI was 0.965 and RFI was 0.920. Thereafter the exogenous latent variables would include knowledge, motivation and psychological effects. The endogenous latent variable appeared as prevention related behaviors. The standardized total effects of motivation, knowledge, psychological on prevention behavior were 0.44, 0.41 and 0.17 respectively. Correlation coefficient of motivation and psychological effects was 0.16. Correlation coefficient on knowledge and psychological effects was -0.17 (Pmotivation did not show statistical significance. Knowledge of HIV and motivation of HIV prevention did not show any accordance in MSM population. It was necessary to increase the awareness and to improve the motivation of HIV prevention in MSM population.

Scene Categorization in Alzheimer's Disease: A Saccadic Choice Task

Directory of Open Access Journals (Sweden)

Quentin Lenoble

2015-01-01

Full Text Available Aims: We investigated the performance in scene categorization of patients with Alzheimer's disease (AD using a saccadic choice task. Method: 24 patients with mild AD, 28 age-matched controls and 26 young people participated in the study. The participants were presented pairs of coloured photographs and were asked to make a saccadic eye movement to the picture corresponding to the target scene (natural vs. urban, indoor vs. outdoor. Results: The patients' performance did not differ from chance for natural scenes. Differences between young and older controls and patients with AD were found in accuracy but not saccadic latency. Conclusions: The results are interpreted in terms of cerebral reorganization in the prefrontal and temporo-occipital cortex of patients with AD, but also in terms of impaired processing of visual global properties of scenes.

Defining spatial relations in a specific ontology for automated scene creation

Directory of Open Access Journals (Sweden)

D. Contraş

2013-06-01

Full Text Available This paper presents the approach of building an ontology for automatic scene generation. Every scene contains various elements (backgrounds, characters, objects which are spatially interrelated. The article focuses on these spatial and temporal relationships of the elements constituting a scene.

"Booze is the main factor that got me where I am today": alcohol use and HIV risk for MSM in rural South Africa.

Science.gov (United States)

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

2018-05-28

Excessive alcohol consumption has been shown to increase HIV risk for men who have sex with men (MSM) and compromise HIV prevention behaviors. However, there is limited contextual understanding of alcohol use for MSM in rural sub-Saharan African settings, which can inform and direct HIV interventions. Applying an adaptation of PhotoVoice, we worked with 35 HIV-positive MSM who created photo-essays about alcohol and HIV in Mpumalanga. A semi-structured protocol was used in focus group discussions that were audio-recorded, translated and transcribed. Transcript data and visual data of 24 photo-essays were analyzed using a constant comparison approach. We found that participants used alcohol to build and sustain social networks, meet sexual partners, and enhance sexual experience. Excessive alcohol use was common, which was associated with increased HIV risk behaviors within a community of MSM who maintained multiple partnerships. Our study suggests that HIV interventions need to address excessive alcohol use to mitigate the associated HIV risk at both the individual and community levels.

Complex scenes and situations visualization in hierarchical learning algorithm with dynamic 3D NeoAxis engine

Science.gov (United States)

Graham, James; Ternovskiy, Igor V.

2013-06-01

We applied a two stage unsupervised hierarchical learning system to model complex dynamic surveillance and cyber space monitoring systems using a non-commercial version of the NeoAxis visualization software. The hierarchical scene learning and recognition approach is based on hierarchical expectation maximization, and was linked to a 3D graphics engine for validation of learning and classification results and understanding the human - autonomous system relationship. Scene recognition is performed by taking synthetically generated data and feeding it to a dynamic logic algorithm. The algorithm performs hierarchical recognition of the scene by first examining the features of the objects to determine which objects are present, and then determines the scene based on the objects present. This paper presents a framework within which low level data linked to higher-level visualization can provide support to a human operator and be evaluated in a detailed and systematic way.

Scene perception in posterior cortical atrophy: categorization, description and fixation patterns.

Science.gov (United States)

Shakespeare, Timothy J; Yong, Keir X X; Frost, Chris; Kim, Lois G; Warrington, Elizabeth K; Crutch, Sebastian J

2013-01-01

Partial or complete Balint's syndrome is a core feature of the clinico-radiological syndrome of posterior cortical atrophy (PCA), in which individuals experience a progressive deterioration of cortical vision. Although multi-object arrays are frequently used to detect simultanagnosia in the clinical assessment and diagnosis of PCA, to date there have been no group studies of scene perception in patients with the syndrome. The current study involved three linked experiments conducted in PCA patients and healthy controls. Experiment 1 evaluated the accuracy and latency of complex scene perception relative to individual faces and objects (color and grayscale) using a categorization paradigm. PCA patients were both less accurate (faces < scenes < objects) and slower (scenes < objects < faces) than controls on all categories, with performance strongly associated with their level of basic visual processing impairment; patients also showed a small advantage for color over grayscale stimuli. Experiment 2 involved free description of real world scenes. PCA patients generated fewer features and more misperceptions than controls, though perceptual errors were always consistent with the patient's global understanding of the scene (whether correct or not). Experiment 3 used eye tracking measures to compare patient and control eye movements over initial and subsequent fixations of scenes. Patients' fixation patterns were significantly different to those of young and age-matched controls, with comparable group differences for both initial and subsequent fixations. Overall, these findings describe the variability in everyday scene perception exhibited by individuals with PCA, and indicate the importance of exposure duration in the perception of complex scenes.

Scene perception in Posterior Cortical Atrophy: categorisation, description and fixation patterns

Directory of Open Access Journals (Sweden)

Timothy J Shakespeare

2013-10-01

Full Text Available Partial or complete Balint’s syndrome is a core feature of the clinico-radiological syndrome of posterior cortical atrophy (PCA, in which individuals experience a progressive deterioration of cortical vision. Although multi-object arrays are frequently used to detect simultanagnosia in the clinical assessment and diagnosis of PCA, to date there have been no group studies of scene perception in patients with the syndrome. The current study involved three linked experiments conducted in PCA patients and healthy controls. Experiment 1 evaluated the accuracy and latency of complex scene perception relative to individual faces and objects (colour and greyscale using a categorisation paradigm. PCA patients were both less accurate (faces<scenesscenesscenes. PCA patients generated fewer features and more misperceptions than controls, though perceptual errors were always consistent with the patient’s global understanding of the scene (whether correct or not. Experiment 3 used eye tracking measures to compare patient and control eye movements over initial and subsequent fixations of scenes. Patients’ fixation patterns were significantly different to those of young and age-matched controls, with comparable group differences for both initial and subsequent fixations. Overall, these findings describe the variability in everyday scene perception exhibited by individuals with PCA, and indicate the importance of exposure duration in the perception of complex scenes.

AR goggles make crime scene investigation a desk job

OpenAIRE

Aron, Jacob; NORTHFIELD, Dean

2012-01-01

CRIME scene investigators could one day help solve murders without leaving the office. A pair of augmented reality glasses could allow local police to virtually tag objects in a crime scene, and build a clean record of the scene in 3D video before evidence is removed for processing.\\ud The system, being developed by Oytun Akman and colleagues at the Delft University of Technology in the Netherlands, consists of a head-mounted display receiving 3D video from a pair of attached cameras controll...

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.

Hebbian learning in a model with dynamic rate-coded neurons: an alternative to the generative model approach for learning receptive fields from natural scenes.

Science.gov (United States)

Hamker, Fred H; Wiltschut, Jan

2007-09-01

Most computational models of coding are based on a generative model according to which the feedback signal aims to reconstruct the visual scene as close as possible. We here explore an alternative model of feedback. It is derived from studies of attention and thus, probably more flexible with respect to attentive processing in higher brain areas. According to this model, feedback implements a gain increase of the feedforward signal. We use a dynamic model with presynaptic inhibition and Hebbian learning to simultaneously learn feedforward and feedback weights. The weights converge to localized, oriented, and bandpass filters similar as the ones found in V1. Due to presynaptic inhibition the model predicts the organization of receptive fields within the feedforward pathway, whereas feedback primarily serves to tune early visual processing according to the needs of the task.

Oculomotor capture during real-world scene viewing depends on cognitive load.

Science.gov (United States)

Matsukura, Michi; Brockmole, James R; Boot, Walter R; Henderson, John M

2011-03-25

It has been claimed that gaze control during scene viewing is largely governed by stimulus-driven, bottom-up selection mechanisms. Recent research, however, has strongly suggested that observers' top-down control plays a dominant role in attentional prioritization in scenes. A notable exception to this strong top-down control is oculomotor capture, where visual transients in a scene draw the eyes. One way to test whether oculomotor capture during scene viewing is independent of an observer's top-down goal setting is to reduce observers' cognitive resource availability. In the present study, we examined whether increasing observers' cognitive load influences the frequency and speed of oculomotor capture during scene viewing. In Experiment 1, we tested whether increasing observers' cognitive load modulates the degree of oculomotor capture by a new object suddenly appeared in a scene. Similarly, in Experiment 2, we tested whether increasing observers' cognitive load modulates the degree of oculomotor capture by an object's color change. In both experiments, the degree of oculomotor capture decreased as observers' cognitive resources were reduced. These results suggest that oculomotor capture during scene viewing is dependent on observers' top-down selection mechanisms. Copyright © 2011 Elsevier Ltd. All rights reserved.

Gay and Lesbian Scene in Metelkova

Directory of Open Access Journals (Sweden)

Nataša Velikonja

2013-09-01

Full Text Available The article deals with the development of the gay and lesbian scene in ACC Metelkova, while specifying the preliminary aspects of establishing and building gay and lesbian activism associated with spatial issues. The struggle for space or occupying public space is vital for the gay and lesbian scene, as it provides not only the necessary socializing opportunities for gays and lesbians, but also does away with the historical hiding of homosexuality in the closet, in seclusion and silence. Because of their autonomy and long-term, continuous existence, homo-clubs at Metelkova contributed to the consolidation of the gay and lesbian scene in Slovenia and significantly improved the opportunities for cultural, social and political expression of gays and lesbians. Such a synthesis of the cultural, social and political, further intensified in Metelkova, and characterizes the gay and lesbian community in Slovenia from the very outset of gay and lesbian activism in 1984. It is this long-term synthesis that keeps this community in Slovenia so vital and politically resilient.

Detecting anomalies in crowded scenes via locality-constrained affine subspace coding

Science.gov (United States)

Fan, Yaxiang; Wen, Gongjian; Qiu, Shaohua; Li, Deren

2017-07-01

Video anomaly event detection is the process of finding an abnormal event deviation compared with the majority of normal or usual events. The main challenges are the high structure redundancy and the dynamic changes in the scenes that are in surveillance videos. To address these problems, we present a framework for anomaly detection and localization in videos that is based on locality-constrained affine subspace coding (LASC) and a model updating procedure. In our algorithm, LASC attempts to reconstruct the test sample by its top-k nearest subspaces, which are obtained by segmenting the normal samples space using a clustering method. A sample with a large reconstruction cost is detected as abnormal by setting a threshold. To adapt to the scene changes over time, a model updating strategy is proposed. We experiment on two public datasets: the UCSD dataset and the Avenue dataset. The results demonstrate that our method achieves competitive performance at a 700 fps on a single desktop PC.

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.

The Role of Ge Wetting Layer and Ge Islands in Si MSM Photodetectors

International Nuclear Information System (INIS)

Mahmodi, H.; Hashim, M. R.

2010-01-01

In this work, Ge thin films were deposited on silicon substrates by radio frequency magnetron sputtering to form Ge islands from Ge layer on Si substrate during post-growth rapid thermal annealing (RTA). The size of the islands decreases from 0.6 to 0.1 as the rapid thermal annealing time increases from 30 s to 60 s at 900 deg. C. Not only that the annealing produces Ge islands but also wetting layer. Energy Dispersive X-ray Spectroscopy (EDX) and Scanning Electron Microscopy (SEM) were employed for structural analysis of Ge islands. Metal-Semiconductor-Metal photodetectors (MSM PDs) were fabricated on Ge islands (and wetting layer)/Si. The Ge islands and wetting layer between the contacts of the fabricated devices are etched in order to see their effects on the device. The performance of the Ge islands MSM-PD was evaluated by dark and photo current-voltage (I-V) measurements at room temperature (RT). It was found that the device with island and wetting layer significantly enhance the current gain (ratio of photo current to dark current) of the device.

Integration of heterogeneous features for remote sensing scene classification

Science.gov (United States)

Wang, Xin; Xiong, Xingnan; Ning, Chen; Shi, Aiye; Lv, Guofang

2018-01-01

Scene classification is one of the most important issues in remote sensing (RS) image processing. We find that features from different channels (shape, spectral, texture, etc.), levels (low-level and middle-level), or perspectives (local and global) could provide various properties for RS images, and then propose a heterogeneous feature framework to extract and integrate heterogeneous features with different types for RS scene classification. The proposed method is composed of three modules (1) heterogeneous features extraction, where three heterogeneous feature types, called DS-SURF-LLC, mean-Std-LLC, and MS-CLBP, are calculated, (2) heterogeneous features fusion, where the multiple kernel learning (MKL) is utilized to integrate the heterogeneous features, and (3) an MKL support vector machine classifier for RS scene classification. The proposed method is extensively evaluated on three challenging benchmark datasets (a 6-class dataset, a 12-class dataset, and a 21-class dataset), and the experimental results show that the proposed method leads to good classification performance. It produces good informative features to describe the RS image scenes. Moreover, the integration of heterogeneous features outperforms some state-of-the-art features on RS scene classification tasks.

Simulator scene display evaluation device

Science.gov (United States)

Haines, R. F. (Inventor)

1986-01-01

An apparatus for aligning and calibrating scene displays in an aircraft simulator has a base on which all of the instruments for the aligning and calibrating are mounted. Laser directs beam at double right prism which is attached to pivoting support on base. The pivot point of the prism is located at the design eye point (DEP) of simulator during the aligning and calibrating. The objective lens in the base is movable on a track to follow the laser beam at different angles within the field of vision at the DEP. An eyepiece and a precision diopter are movable into a position behind the prism during the scene evaluation. A photometer or illuminometer is pivotable about the pivot into and out of position behind the eyepiece.

Parallel programming of saccades during natural scene viewing: evidence from eye movement positions.

Science.gov (United States)

Wu, Esther X W; Gilani, Syed Omer; van Boxtel, Jeroen J A; Amihai, Ido; Chua, Fook Kee; Yen, Shih-Cheng

2013-10-24

Previous studies have shown that saccade plans during natural scene viewing can be programmed in parallel. This evidence comes mainly from temporal indicators, i.e., fixation durations and latencies. In the current study, we asked whether eye movement positions recorded during scene viewing also reflect parallel programming of saccades. As participants viewed scenes in preparation for a memory task, their inspection of the scene was suddenly disrupted by a transition to another scene. We examined whether saccades after the transition were invariably directed immediately toward the center or were contingent on saccade onset times relative to the transition. The results, which showed a dissociation in eye movement behavior between two groups of saccades after the scene transition, supported the parallel programming account. Saccades with relatively long onset times (>100 ms) after the transition were directed immediately toward the center of the scene, probably to restart scene exploration. Saccades with short onset times (programming of saccades during scene viewing. Additionally, results from the analyses of intersaccadic intervals were also consistent with the parallel programming hypothesis.

Motivational Objects in Natural Scenes (MONS: A Database of >800 Objects

Directory of Open Access Journals (Sweden)

Judith Schomaker

2017-09-01

Full Text Available In daily life, we are surrounded by objects with pre-existing motivational associations. However, these are rarely controlled for in experiments with natural stimuli. Research on natural stimuli would therefore benefit from stimuli with well-defined motivational properties; in turn, such stimuli also open new paths in research on motivation. Here we introduce a database of Motivational Objects in Natural Scenes (MONS. The database consists of 107 scenes. Each scene contains 2 to 7 objects placed at approximately equal distance from the scene center. Each scene was photographed creating 3 versions, with one object (“critical object” being replaced to vary the overall motivational value of the scene (appetitive, aversive, and neutral, while maintaining high visual similarity between the three versions. Ratings on motivation, valence, arousal and recognizability were obtained using internet-based questionnaires. Since the main objective was to provide stimuli of well-defined motivational value, three motivation scales were used: (1 Desire to own the object; (2 Approach/Avoid; (3 Desire to interact with the object. Three sets of ratings were obtained in independent sets of observers: for all 805 objects presented on a neutral background, for 321 critical objects presented in their scene context, and for the entire scenes. On the basis of the motivational ratings, objects were subdivided into aversive, neutral, and appetitive categories. The MONS database will provide a standardized basis for future studies on motivational value under realistic conditions.

Motivational Objects in Natural Scenes (MONS): A Database of >800 Objects.

Science.gov (United States)

Schomaker, Judith; Rau, Elias M; Einhäuser, Wolfgang; Wittmann, Bianca C

2017-01-01

In daily life, we are surrounded by objects with pre-existing motivational associations. However, these are rarely controlled for in experiments with natural stimuli. Research on natural stimuli would therefore benefit from stimuli with well-defined motivational properties; in turn, such stimuli also open new paths in research on motivation. Here we introduce a database of Motivational Objects in Natural Scenes (MONS). The database consists of 107 scenes. Each scene contains 2 to 7 objects placed at approximately equal distance from the scene center. Each scene was photographed creating 3 versions, with one object ("critical object") being replaced to vary the overall motivational value of the scene (appetitive, aversive, and neutral), while maintaining high visual similarity between the three versions. Ratings on motivation, valence, arousal and recognizability were obtained using internet-based questionnaires. Since the main objective was to provide stimuli of well-defined motivational value, three motivation scales were used: (1) Desire to own the object; (2) Approach/Avoid; (3) Desire to interact with the object. Three sets of ratings were obtained in independent sets of observers: for all 805 objects presented on a neutral background, for 321 critical objects presented in their scene context, and for the entire scenes. On the basis of the motivational ratings, objects were subdivided into aversive, neutral, and appetitive categories. The MONS database will provide a standardized basis for future studies on motivational value under realistic conditions.

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

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

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

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.

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...... structures of the type-scene in order to show how Jesus’ true identity can be recognized behind the half-mask of his human appearance....

Memory for sound, with an ear toward hearing in complex auditory scenes.

Science.gov (United States)

Snyder, Joel S; Gregg, Melissa K

2011-10-01

An area of research that has experienced recent growth is the study of memory during perception of simple and complex auditory scenes. These studies have provided important information about how well auditory objects are encoded in memory and how well listeners can notice changes in auditory scenes. These are significant developments because they present an opportunity to better understand how we hear in realistic situations, how higher-level aspects of hearing such as semantics and prior exposure affect perception, and the similarities and differences between auditory perception and perception in other modalities, such as vision and touch. The research also poses exciting challenges for behavioral and neural models of how auditory perception and memory work.

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.

Problem drinking is associated with increased prevalence of sexual risk behaviors among men who have sex with men (MSM) in Lima, Peru.

Science.gov (United States)

Deiss, Robert G; Clark, Jesse L; Konda, Kelika A; Leon, Segundo R; Klausner, Jeffrey D; Caceres, Carlos F; Coates, Thomas J

2013-09-01

Alcohol use is an important but understudied HIV risk factor among men who have sex with men (MSM), particularly in Latin America. We studied the relationship between problem drinking and sexual risk among MSM in Lima, Peru. We recruited 718 participants from 24 neighborhoods for a study on sexually transmitted infections and community-building among MSM. Multivariate analysis was used to identify factors independently associated with problem drinking, which was defined via the CAGE Questionnaire. Of 718 participants, 58% met criteria for problem drinking. In univariate analysis, problem drinkers were significantly more likely to report failing to always use condoms, use alcohol or drugs prior to their most recent sexual encounter, report a history of sexual coercion and to engage in transactional sex. Problem drinkers also reported significantly higher numbers of recent and lifetime sexual partners. In multivariate analysis, factors independently associated with problem drinking included a history of sexual coercion [OR 1.8 95%, CI 1.2-2.6], having consumed alcohol prior to the most recent sexual encounter [OR 2.1 95%, CI 1.5-2.9], receiving compensation for sex in the last six months [OR 1.6, 95% CI 1.1-2.2] or having reported a prior HIV+ test [OR 0.5, 95% CI 0.2-0.9]. We found a high prevalence of problem drinking among MSM in Lima, Peru, which was associated with increased sexual risk in our study. Of note, individuals who were already HIV-infected were less likely to be problem drinkers. Further studies and targeted interventions to reduce problem drinking among MSM are warranted. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Effects of aging on neural connectivity underlying selective memory for emotional scenes.

Science.gov (United States)

Waring, Jill D; Addis, Donna Rose; Kensinger, Elizabeth A

2013-02-01

Older adults show age-related reductions in memory for neutral items within complex visual scenes, but just like young adults, older adults exhibit a memory advantage for emotional items within scenes compared with the background scene information. The present study examined young and older adults' encoding-stage effective connectivity for selective memory of emotional items versus memory for both the emotional item and its background. In a functional magnetic resonance imaging (fMRI) study, participants viewed scenes containing either positive or negative items within neutral backgrounds. Outside the scanner, participants completed a memory test for items and backgrounds. Irrespective of scene content being emotionally positive or negative, older adults had stronger positive connections among frontal regions and from frontal regions to medial temporal lobe structures than did young adults, especially when items and backgrounds were subsequently remembered. These results suggest there are differences between young and older adults' connectivity accompanying the encoding of emotional scenes. Older adults may require more frontal connectivity to encode all elements of a scene rather than just encoding the emotional item. Published by Elsevier Inc.

Unconscious analyses of visual scenes based on feature conjunctions.

Science.gov (United States)

Tachibana, Ryosuke; Noguchi, Yasuki

2015-06-01

To efficiently process a cluttered scene, the visual system analyzes statistical properties or regularities of visual elements embedded in the scene. It is controversial, however, whether those scene analyses could also work for stimuli unconsciously perceived. Here we show that our brain performs the unconscious scene analyses not only using a single featural cue (e.g., orientation) but also based on conjunctions of multiple visual features (e.g., combinations of color and orientation information). Subjects foveally viewed a stimulus array (duration: 50 ms) where 4 types of bars (red-horizontal, red-vertical, green-horizontal, and green-vertical) were intermixed. Although a conscious perception of those bars was inhibited by a subsequent mask stimulus, the brain correctly analyzed the information about color, orientation, and color-orientation conjunctions of those invisible bars. The information of those features was then used for the unconscious configuration analysis (statistical processing) of the central bars, which induced a perceptual bias and illusory feature binding in visible stimuli at peripheral locations. While statistical analyses and feature binding are normally 2 key functions of the visual system to construct coherent percepts of visual scenes, our results show that a high-level analysis combining those 2 functions is correctly performed by unconscious computations in the brain. (c) 2015 APA, all rights reserved).

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.

The provider perception inventory: psychometrics of a scale designed to measure provider stigma about HIV, substance abuse, and MSM behavior.

Science.gov (United States)

Windsor, Liliane C; Benoit, Ellen; Ream, Geoffrey L; Forenza, Brad

2013-01-01

Nongay identified men who have sex with men and women (NGI MSMW) and who use alcohol and other drugs are a vulnerable, understudied, and undertreated population. Little is known about the stigma faced by this population or about the way that health service providers view and serve these stigmatized clients. The provider perception inventory (PPI) is a 39-item scale that measures health services providers' stigma about HIV/AIDS, substance use, and MSM behavior. The PPI is unique in that it was developed to include service provider stigma targeted at NGI MSMW individuals. PPI was developed through a mixed methods approach. Items were developed based on existing measures and findings from focus groups with 18 HIV and substance abuse treatment providers. Exploratory factor analysis using data from 212 health service providers yielded a two dimensional scale: (1) individual attitudes (19 items) and (2) agency environment (11 items). Structural equation modeling analysis supported the scale's predictive validity (N=190 sufficiently complete cases). Overall findings indicate initial support for the psychometrics of the PPI as a measure of service provider stigma pertaining to the intersection of HIV/AIDS, substance use, and MSM behavior. Limitations and implications to future research are discussed.

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.

The influence of perception and peer support on STI prevention behavior (syphilis case study) in group of MSM at veterans STI-VCT clinic in Medan year 2016

Science.gov (United States)

Sukatendel, K.; Napitupulu, T. E.; Rusmalawati; Andayani, L. S.; Yustina, I.

2018-03-01

According to Behavioral and Biological Integrated Surveillance (BBIS) in Indonesia, 2011, there was an increase in syphilis surveillance in men who like to commit sexual intercourse with other men (MSM). It was 13% of the 3% in BBIS 2007 in bad STI prevention behavior. There were 478 MSM have visited STI-VCT clinic in Medan throughout 2015, and syphilis-infected 59 men. This study aims to analyze the influence of perception and peer support on prevention of STI in MSM at Veteran STI-VCT Clinic in Medan, 2016. It was a mixed method quantitative and qualitative study with the cross-sectional approach, enrolled 50 respondents. Data were collected and analyzed with SPSS 19. There was the influence of perception and peer support on STI prevention behavior of MSM group at STI-VCT Veteran Clinic in Medan.

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…

SAMPEG: a scene-adaptive parallel MPEG-2 software encoder

NARCIS (Netherlands)

Farin, D.S.; Mache, N.; With, de P.H.N.; Girod, B.; Bouman, C.A.; Steinbach, E.G.

2001-01-01

This paper presents a fully software-based MPEG-2 encoder architecture, which uses scene-change detection to optimize the Group-of-Picture (GOP) structure for the actual video sequence. This feature enables easy, lossless edit cuts at scene-change positions and it also improves overall picture

Community-based prevention leads to an increase in condom use and a reduction in sexually transmitted infections (STIs among men who have sex with men (MSM and female sex workers (FSW: the Frontiers Prevention Project (FPP evaluation results

Directory of Open Access Journals (Sweden)

Gutierrez Juan-Pablo

2010-08-01

Full Text Available Abstract Background India has an estimated 2.0 million to 3.1 million people living with HIV; it has the highest number of HIV-positive people in Asia and ranks third in the world. The Frontiers Prevention Project (FPP was implemented in 2002 to conduct targeted prevention intervention geared towards female sex workers (FSW and men who have sex with men (MSM in the state of Andhra Pradesh (AP. This paper reports the overall changes in behaviour and STI outcomes between 2003/4 and 2007 and also describes the changes attributed to the FPP. Methods The evaluation used two cross-sectional surveys among MSM and FSW at 24 sites in AP. Surveys were implemented using a similar methodology. Univariate analyses were conducted by comparing means: baseline vs. four-year follow-up and FPP vs. non-FPP. For both MSM and FSW, random and fixed-effects logit regression models at the site level were estimated for condom use with last partner, syphilis sero-positivity and HSV 2 sero-positivity. In addition, for FSW we estimated models for condom use with regular partner, and for MSM we estimated models for condom use with last female partner. Results Among MSM, fixed-effects analysis revealed that FPP was positively correlated with the probability of condom use with last female sexual partner and negatively correlated with the individual probability of sero-positivity to syphilis and HSV 2. Among FSW, the FPP intervention was significantly correlated with increased condom use with regular partners and with lower probability of STI sero-positivity. Discussion Important changes in behaviours related to an increase in prevention activities translated to reductions in STI sero-prevalence in AP, India. In contrast with non-FPP sites, the FPP sites experienced an intense community approach as part of the FPP intervention, and the general increase in condom use and its effect on STI sero-prevalence reflected the efficacy of these intense prevention activities focused on

Clandestine laboratory scene investigation and processing using portable GC/MS

Science.gov (United States)

Matejczyk, Raymond J.

1997-02-01

This presentation describes the use of portable gas chromatography/mass spectrometry for on-scene investigation and processing of clandestine laboratories. Clandestine laboratory investigations present special problems to forensic investigators. These crime scenes contain many chemical hazards that must be detected, identified and collected as evidence. Gas chromatography/mass spectrometry performed on-scene with a rugged, portable unit is capable of analyzing a variety of matrices for drugs and chemicals used in the manufacture of illicit drugs, such as methamphetamine. Technologies used to detect various materials at a scene have particular applications but do not address the wide range of samples, chemicals, matrices and mixtures that exist in clan labs. Typical analyses performed by GC/MS are for the purpose of positively establishing the identity of starting materials, chemicals and end-product collected from clandestine laboratories. Concerns for the public and investigator safety and the environment are also important factors for rapid on-scene data generation. Here is described the implementation of a portable multiple-inlet GC/MS system designed for rapid deployment to a scene to perform forensic investigations of clandestine drug manufacturing laboratories. GC/MS has long been held as the 'gold standard' in performing forensic chemical analyses. With the capability of GC/MS to separate and produce a 'chemical fingerprint' of compounds, it is utilized as an essential technique for detecting and positively identifying chemical evidence. Rapid and conclusive on-scene analysis of evidence will assist the forensic investigators in collecting only pertinent evidence thereby reducing the amount of evidence to be transported, reducing chain of custody concerns, reducing costs and hazards, maintaining sample integrity and speeding the completion of the investigative process.

Viewing nature scenes positively affects recovery of autonomic function following acute-mental stress.

Science.gov (United States)

Brown, Daniel K; Barton, Jo L; Gladwell, Valerie F

2013-06-04

A randomized crossover study explored whether viewing different scenes prior to a stressor altered autonomic function during the recovery from the stressor. The two scenes were (a) nature (composed of trees, grass, fields) or (b) built (composed of man-made, urban scenes lacking natural characteristics) environments. Autonomic function was assessed using noninvasive techniques of heart rate variability; in particular, time domain analyses evaluated parasympathetic activity, using root-mean-square of successive differences (RMSSD). During stress, secondary cardiovascular markers (heart rate, systolic and diastolic blood pressure) showed significant increases from baseline which did not differ between the two viewing conditions. Parasympathetic activity, however, was significantly higher in recovery following the stressor in the viewing scenes of nature condition compared to viewing scenes depicting built environments (RMSSD; 50.0 ± 31.3 vs 34.8 ± 14.8 ms). Thus, viewing nature scenes prior to a stressor alters autonomic activity in the recovery period. The secondary aim was to examine autonomic function during viewing of the two scenes. Standard deviation of R-R intervals (SDRR), as change from baseline, during the first 5 min of viewing nature scenes was greater than during built scenes. Overall, this suggests that nature can elicit improvements in the recovery process following a stressor.

Predicting top-of-atmosphere radiance for arbitrary viewing geometries from the visible to thermal infrared: generalization to arbitrary average scene temperatures

Science.gov (United States)

Florio, Christopher J.; Cota, Steve A.; Gaffney, Stephanie K.

2010-08-01

In a companion paper presented at this conference we described how The Aerospace Corporation's Parameterized Image Chain Analysis & Simulation SOftware (PICASSO) may be used in conjunction with a limited number of runs of AFRL's MODTRAN4 radiative transfer code, to quickly predict the top-of-atmosphere (TOA) radiance received in the visible through midwave IR (MWIR) by an earth viewing sensor, for any arbitrary combination of solar and sensor elevation angles. The method is particularly useful for large-scale scene simulations where each pixel could have a unique value of reflectance/emissivity and temperature, making the run-time required for direct prediction via MODTRAN4 prohibitive. In order to be self-consistent, the method described requires an atmospheric model (defined, at a minimum, as a set of vertical temperature, pressure and water vapor profiles) that is consistent with the average scene temperature. MODTRAN4 provides only six model atmospheres, ranging from sub-arctic winter to tropical conditions - too few to cover with sufficient temperature resolution the full range of average scene temperatures that might be of interest. Model atmospheres consistent with intermediate temperature values can be difficult to come by, and in any event, their use would be too cumbersome for use in trade studies involving a large number of average scene temperatures. In this paper we describe and assess a method for predicting TOA radiance for any arbitrary average scene temperature, starting from only a limited number of model atmospheres.

Syphilis and HIV/Syphilis Co-infection Among Men Who Have Sex With Men (MSM) in Ecuador.

Science.gov (United States)

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

2017-07-01

There is a reemergence of syphilis in the Latin American and Caribbean region. There is also very little information about HIV/Syphilis co-infection and its determinants. The aim of this study is to investigate knowledge, attitudes, and practices regarding sexually transmitted infections (STIs), in particular syphilis infection and HIV/Syphilis co-infection, as well as to estimate the prevalence of syphilis among men who have sex with men (MSM) in a city with one of the highest HIV prevalence rates in Ecuador. In this study, questionnaires were administered to 291 adult MSM. Questions included knowledge about STIs and their sexual practices. Blood samples were taken from participants to estimate the prevalence of syphilis and HIV/syphilis co-infection. In this population, the prevalence of HIV/syphilis co-infection was 4.8%, while the prevalence of syphilis as mono-infection was 6.5%. Participants who had syphilis mono-infection and HIV/syphilis co-infection were older. Men who had multiple partners and those who were forced to have sex had increased odds of syphilis and HIV/syphilis co-infection. A high prevalence of syphilis and self-reported STI was observed, which warrants targeted behavioral interventions. Co-infections are a cause for concern when treating a secondary infection in a person who is immunocompromised. These data suggest that specific knowledge, attitudes, and behaviors among MSM are associated with increased odds of STIs (including HIV/syphilis co-infections) in this region of Ecuador.

Real-time maritime scene simulation for ladar sensors

Science.gov (United States)

Christie, Chad L.; Gouthas, Efthimios; Swierkowski, Leszek; Williams, Owen M.

2011-06-01

Continuing interest exists in the development of cost-effective synthetic environments for testing Laser Detection and Ranging (ladar) sensors. In this paper we describe a PC-based system for real-time ladar scene simulation of ships and small boats in a dynamic maritime environment. In particular, we describe the techniques employed to generate range imagery accompanied by passive radiance imagery. Our ladar scene generation system is an evolutionary extension of the VIRSuite infrared scene simulation program and includes all previous features such as ocean wave simulation, the physically-realistic representation of boat and ship dynamics, wake generation and simulation of whitecaps, spray, wake trails and foam. A terrain simulation extension is also under development. In this paper we outline the development, capabilities and limitations of the VIRSuite extensions.

Open and scalable analytics of large Earth observation datasets: From scenes to multidimensional arrays using SciDB and GDAL

Science.gov (United States)

Appel, Marius; Lahn, Florian; Buytaert, Wouter; Pebesma, Edzer

2018-04-01

Earth observation (EO) datasets are commonly provided as collection of scenes, where individual scenes represent a temporal snapshot and cover a particular region on the Earth's surface. Using these data in complex spatiotemporal modeling becomes difficult as soon as data volumes exceed a certain capacity or analyses include many scenes, which may spatially overlap and may have been recorded at different dates. In order to facilitate analytics on large EO datasets, we combine and extend the geospatial data abstraction library (GDAL) and the array-based data management and analytics system SciDB. We present an approach to automatically convert collections of scenes to multidimensional arrays and use SciDB to scale computationally intensive analytics. We evaluate the approach in three study cases on national scale land use change monitoring with Landsat imagery, global empirical orthogonal function analysis of daily precipitation, and combining historical climate model projections with satellite-based observations. Results indicate that the approach can be used to represent various EO datasets and that analyses in SciDB scale well with available computational resources. To simplify analyses of higher-dimensional datasets as from climate model output, however, a generalization of the GDAL data model might be needed. All parts of this work have been implemented as open-source software and we discuss how this may facilitate open and reproducible EO analyses.

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.

Multi-view 3D scene reconstruction using ant colony optimization techniques

International Nuclear Information System (INIS)

Chrysostomou, Dimitrios; Gasteratos, Antonios; Nalpantidis, Lazaros; Sirakoulis, Georgios C

2012-01-01

This paper presents a new method performing high-quality 3D object reconstruction of complex shapes derived from multiple, calibrated photographs of the same scene. The novelty of this research is found in two basic elements, namely: (i) a novel voxel dissimilarity measure, which accommodates the elimination of the lighting variations of the models and (ii) the use of an ant colony approach for further refinement of the final 3D models. The proposed reconstruction procedure employs a volumetric method based on a novel projection test for the production of a visual hull. While the presented algorithm shares certain aspects with the space carving algorithm, it is, nevertheless, first enhanced with the lightness compensating image comparison method, and then refined using ant colony optimization. The algorithm is fast, computationally simple and results in accurate representations of the input scenes. In addition, compared to previous publications, the particular nature of the proposed algorithm allows accurate 3D volumetric measurements under demanding lighting environmental conditions, due to the fact that it can cope with uneven light scenes, resulting from the characteristics of the voxel dissimilarity measure applied. Besides, the intelligent behavior of the ant colony framework provides the opportunity to formulate the process as a combinatorial optimization problem, which can then be solved by means of a colony of cooperating artificial ants, resulting in very promising results. The method is validated with several real datasets, along with qualitative comparisons with other state-of-the-art 3D reconstruction techniques, following the Middlebury benchmark. (paper)

Cybersickness in the presence of scene rotational movements along different axes.

Science.gov (United States)

Lo, W T; So, R H

2001-02-01

Compelling scene movements in a virtual reality (VR) system can cause symptoms of motion sickness (i.e., cybersickness). A within-subject experiment has been conducted to investigate the effects of scene oscillations along different axes on the level of cybersickness. Sixteen male participants were exposed to four 20-min VR simulation sessions. The four sessions used the same virtual environment but with scene oscillations along different axes, i.e., pitch, yaw, roll, or no oscillation (speed: 30 degrees/s, range: +/- 60 degrees). Verbal ratings of the level of nausea were taken at 5-min intervals during the sessions and sickness symptoms were also measured before and after the sessions using the Simulator Sickness Questionnaire (SSQ). In the presence of scene oscillation, both nausea ratings and SSQ scores increased at significantly higher rates than with no oscillation. While individual participants exhibited different susceptibilities to nausea associated with VR simulation containing scene oscillations along different rotational axes, the overall effects of axis among our group of 16 randomly selected participants were not significant. The main effects of, and interactions among, scene oscillation, duration, and participants are discussed in the paper.

Framework of passive millimeter-wave scene simulation based on material classification

Science.gov (United States)

Park, Hyuk; Kim, Sung-Hyun; Lee, Ho-Jin; Kim, Yong-Hoon; Ki, Jae-Sug; Yoon, In-Bok; Lee, Jung-Min; Park, Soon-Jun

2006-05-01

Over the past few decades, passive millimeter-wave (PMMW) sensors have emerged as useful implements in transportation and military applications such as autonomous flight-landing system, smart weapons, night- and all weather vision system. As an efficient way to predict the performance of a PMMW sensor and apply it to system, it is required to test in SoftWare-In-the-Loop (SWIL). The PMMW scene simulation is a key component for implementation of this simulator. However, there is no commercial on-the-shelf available to construct the PMMW scene simulation; only there have been a few studies on this technology. We have studied the PMMW scene simulation method to develop the PMMW sensor SWIL simulator. This paper describes the framework of the PMMW scene simulation and the tentative results. The purpose of the PMMW scene simulation is to generate sensor outputs (or image) from a visible image and environmental conditions. We organize it into four parts; material classification mapping, PMMW environmental setting, PMMW scene forming, and millimeter-wave (MMW) sensorworks. The background and the objects in the scene are classified based on properties related with MMW radiation and reflectivity. The environmental setting part calculates the following PMMW phenomenology; atmospheric propagation and emission including sky temperature, weather conditions, and physical temperature. Then, PMMW raw images are formed with surface geometry. Finally, PMMW sensor outputs are generated from PMMW raw images by applying the sensor characteristics such as an aperture size and noise level. Through the simulation process, PMMW phenomenology and sensor characteristics are simulated on the output scene. We have finished the design of framework of the simulator, and are working on implementation in detail. As a tentative result, the flight observation was simulated in specific conditions. After implementation details, we plan to increase the reliability of the simulation by data collecting

Joint Multi-scale Convolution Neural Network for Scene Classification of High Resolution Remote Sensing Imagery

Directory of Open Access Journals (Sweden)

ZHENG Zhuo

2018-05-01

Full Text Available High resolution remote sensing imagery scene classification is important for automatic complex scene recognition, which is the key technology for military and disaster relief, etc. In this paper, we propose a novel joint multi-scale convolution neural network (JMCNN method using a limited amount of image data for high resolution remote sensing imagery scene classification. Different from traditional convolutional neural network, the proposed JMCNN is an end-to-end training model with joint enhanced high-level feature representation, which includes multi-channel feature extractor, joint multi-scale feature fusion and Softmax classifier. Multi-channel and scale convolutional extractors are used to extract scene middle features, firstly. Then, in order to achieve enhanced high-level feature representation in a limit dataset, joint multi-scale feature fusion is proposed to combine multi-channel and scale features using two feature fusions. Finally, enhanced high-level feature representation can be used for classification by Softmax. Experiments were conducted using two limit public UCM and SIRI datasets. Compared to state-of-the-art methods, the JMCNN achieved improved performance and great robustness with average accuracies of 89.3% and 88.3% on the two datasets.

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

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.

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.

HDR IMAGING FOR FEATURE DETECTION ON DETAILED ARCHITECTURAL SCENES

Directory of Open Access Journals (Sweden)

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.

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…

Barriers to Access and Adoption of Pre-Exposure Prophylaxis for the Prevention of HIV Among Men Who Have Sex With Men (MSM) in a Relatively Rural State.

Science.gov (United States)

Hubach, Randolph D; Currin, Joseph M; Sanders, Carissa A; Durham, André R; Kavanaugh, Katherine E; Wheeler, Denna L; Croff, Julie M

2017-08-01

Biomedical intervention approaches, including antiretroviral pre-exposure prophylaxis (PrEP), have been demonstrated to reduce HIV incidence among several at-risk populations and to be cost effective. However, there is limited understanding of PrEP access and uptake among men who have sex with men (MSM) residing in relatively rural states. Twenty semistructured interviews were conducted (August-November 2016) to assess opinions of and perceived barriers to accessing and adopting PrEP among MSM residing in Oklahoma. Participants perceived substantial barriers to accessing PrEP including a stigmatizing environment and less access to quality, LGBT-sensitive medical care. Overall, geographic isolation limits access to health providers and resources that support sexual health for Oklahoma MSM. Addressing stigma situated across ecological levels in an effort to increase adoption of PrEP by MSM residing in rural states remains necessary. Without this, social determinants may continue to negatively influence PrEP adoption and sexual health outcomes.

HIV/AIDS stigma among a sample of primarily African American and Latino men who have sex with men (MSM) social media users

OpenAIRE

Garett, Renee; Smith, Justin; Chiu, Jason; Young, Sean D.

2016-01-01

The recent increase in social media use allows these technologies to rapidly reach communities with higher HIV prevalence, such as African American and Latino men who have sex with men (MSM). However, no studies have looked at HIV/AIDS stigma among social media users from African American and Latino MSM communities, or the association between stigma and social media use among these groups. This study sought to assess the level of HIV/AIDS stigma among a sample of social media-using African Am...

The time course of natural scene perception with reduced attention

NARCIS (Netherlands)

Groen, I.I.A.; Ghebreab, S.; Lamme, V.A.F.; Scholte, H.S.

Attention is thought to impose an informational bottleneck on vision by selecting particular information from visual scenes for enhanced processing. Behavioral evidence suggests, however, that some scene information is extracted even when attention is directed elsewhere. Here, we investigated the

Uptake of PrEP and condom and sexual risk behavior among MSM during the ANRS IPERGAY trial.

Science.gov (United States)

Sagaon-Teyssier, Luis; Suzan-Monti, Marie; Demoulin, Baptiste; Capitant, Catherine; Lorente, Nicolas; Préau, Marie; Mora, Marion; Rojas Castro, Daniela; Chidiac, Christian; Chas, Julie; Meyer, Laurence; Molina, Jean-Michel; Spire, Bruno

2016-01-01

The double-blind phase of the randomized ANRS IPERGAY trial, evaluating sexual activity-based oral HIV pre-exposure prophylaxis (PrEP), was conducted among high-risk men who have sex with men (MSM). Results showed an 86% (95% CI: 40-98) relative reduction in HIV incidence among participants with tenofovir disoproxil fumarate-emtricitabine vs. placebo. The present pooled analysis aimed to analyze (i) participants' adherence to the prescribed treatment and/or condom use during sexual intercourse and (ii) sexual behavior during the double-blind phase of the study. Four hundred MSM were enrolled in the trial. Every 2 months they completed online questionnaires collecting sexual behavior and PrEP adherence data regarding their most recent sexual intercourse. A total of 2232 questionnaires (M0-M24) were analyzed. Changes over time were evaluated using a mixed model accounting for multiple measures. Irrespective of sexual partner and practice type, on average, 42.6% (min: 32.1-max: 45.8%) reported PrEP use only during their most recent episode of sexual intercourse; 29% (22.9-35.6%) reported both PrEP and condom use; 11.7% (7.2-18.9%) reported condom-use only, and 16.7% (10.8-29.6%) reported no PrEP or condom use with no significant change during the study. Scheduled (i.e., correct) PrEP use was reported on average by 59.0% (47.2-68.5%) of those reporting PrEP use during their most recent sexual intercourse. Overall, 70.3% (65.3-79.4%) and 69.3% (58.3-75.4%) of participants reported, respectively, condomless anal and condomless receptive anal intercourse during their most recent sexual encounter without significant change during follow-up. Overall, on average 83.3% (min: 70.4-max: 89.2%) of participants protected themselves by PrEP intake or condom use or both during the trial, and no increase in at-risk sexual practices was observed. None of these indicators showed significant trend during the follow-up, although we found a tendency toward decrease (p = .19) of the

Research shows 'poppers' use in connected with infection among MSM. Little is done to address problem.

Science.gov (United States)

2004-06-01

Researchers and experts on the use of inhaled nitrates among men who have sex with men (MSM) say clinicians, public health officials, and AIDS groups are ignoring the impact of poppers, a popular party inhalant, on HIV risk behaviors and even seroconversion.

A Two-Stream Deep Fusion Framework for High-Resolution Aerial Scene Classification

Directory of Open Access Journals (Sweden)

Yunlong Yu

2018-01-01

Full Text Available One of the challenging problems in understanding high-resolution remote sensing images is aerial scene classification. A well-designed feature representation method and classifier can improve classification accuracy. In this paper, we construct a new two-stream deep architecture for aerial scene classification. First, we use two pretrained convolutional neural networks (CNNs as feature extractor to learn deep features from the original aerial image and the processed aerial image through saliency detection, respectively. Second, two feature fusion strategies are adopted to fuse the two different types of deep convolutional features extracted by the original RGB stream and the saliency stream. Finally, we use the extreme learning machine (ELM classifier for final classification with the fused features. The effectiveness of the proposed architecture is tested on four challenging datasets: UC-Merced dataset with 21 scene categories, WHU-RS dataset with 19 scene categories, AID dataset with 30 scene categories, and NWPU-RESISC45 dataset with 45 challenging scene categories. The experimental results demonstrate that our architecture gets a significant classification accuracy improvement over all state-of-the-art references.

Recognition and attention guidance during contextual cueing in real-world scenes: evidence from eye movements.

Science.gov (United States)

Brockmole, James R; Henderson, John M

2006-07-01

When confronted with a previously encountered scene, what information is used to guide search to a known target? We contrasted the role of a scene's basic-level category membership with its specific arrangement of visual properties. Observers were repeatedly shown photographs of scenes that contained consistently but arbitrarily located targets, allowing target positions to be associated with scene content. Learned scenes were then unexpectedly mirror reversed, spatially translating visual features as well as the target across the display while preserving the scene's identity and concept. Mirror reversals produced a cost as the eyes initially moved toward the position in the display in which the target had previously appeared. The cost was not complete, however; when initial search failed, the eyes were quickly directed to the target's new position. These results suggest that in real-world scenes, shifts of attention are initially based on scene identity, and subsequent shifts are guided by more detailed information regarding scene and object layout.

Experiences of HIV postexposure prophylaxis (PEP) among highly exposed men who have sex with men (MSM).

Science.gov (United States)

Palich, Romain; Martin-Blondel, Guillaume; Cuzin, Lise; Le Talec, Jean-Yves; Boyer, Pierre; Massip, Patrice; Delobel, Pierre

2017-11-01

HIV postexposure prophylaxis (PEP) is indicated after sexual exposure with high risk of transmission. Men who have sex with men (MSM) are the main target of PEP. The aim of our study was to investigate the experience and shortcomings of PEP among people with a high risk of HIV exposure. Subjects with ongoing follow-up for HIV infection and PEP history were selected for the qualitative study. Semistructured interviews were conducted at the patients' homes. They were audio-recorded, transcribed and deidentified before data analysis, double coding and thematic analysis with an inductive approach. Twenty-three patients were eligible for the qualitative study. Thirteen interviews were carried out. All patients were 20-60-year-old MSM. The median time between PEP and HIV diagnosis was 3.3 years (interquartile range (IQR) 25-75 =0.9-4.9). Many participants reported negative PEP experiences: awkward access to the PEP clinic, uneasiness and shame in the hospital setting, unpleasant interaction and moral disapprobation from the medical staff, treatment intolerance and prevention messages that were 'inconsistent with real life' CONCLUSION: Our data highlight PEP management failures among its target population that may have compromised any subsequent attempts to seek out PEP. Practitioners should be more aware of MSM sexual contexts and practices. PEP consultations should provide the opportunity to discuss prevention strategies with highly exposed HIV-negative subjects, which may include pre-exposure prophylaxis. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Amphetamine-Type-Stimulants (ATS) Use and Homosexuality-Related Enacted Stigma Are Associated With Depression Among Men Who Have Sex With Men (MSM) in Two Major Cities in Vietnam in 2014.

Science.gov (United States)

Vu, Nga Thi Thu; Holt, Martin; Phan, Huong Thi Thu; La, Lan Thi; Tran, Gioi Minh; Doan, Tung Thanh; Nguyen, Trang Nguyen Nhu; de Wit, John

2017-09-19

Men who have sex with men (MSM) are disproportionately affected by mental health concerns, including depression. Amphetamine-type-stimulants (ATS) use and homosexuality-related stigma and discrimination have been found associated with depression among MSM. To assess the prevalence of depression and its associations with ATS use and homosexuality-related stigma and discrimination among MSM in Vietnam. 622 MSM were conveniently recruited in Hanoi and Ho Chi Minh city, Vietnam, from September to December 2014. We collected information on demographic characteristics, ATS, alcohol and other drug use, sexual behaviors, homosexuality-related and discrimination stigma, and sexual sensation-seeking. Depression and suicidal thoughts were assessed by the Patient Health Questionnaire (PHQ-9). We assessed associations of depression with ATS use and homosexuality-related stigma and discrimination using logistic regression. Of 622 sampled MSM, 11.3% were classified as having major depression, 9.8% reported any suicidal thoughts in the last two weeks, 30.4% ever had used any ATS, 88.8% ever ad drank alcohol and 21.5% had ever used any other drugs. In multivariate analysis, depression was significantly associated with ATS use (Adjusted Odds Ratio [AOR: 2.20; (95% Confidence Interval (CI): 1.32-3.67], younger age of sexual debut with another man (AOR: 0.09; 95% CI: 0.02-0.50), and greater enacted homosexuality-related stigma (AOR: 1.97; 95% CI: 1.19-3.26). We found a moderate prevalence of depression among sampled MSM, which was associated with ATS use and enacted homosexuality-related stigma. We recommend integrating assessment and interventions regarding depression and methamphetamine use into gay-friendly, culturally adapted holistic HIV prevention for MSM in Vietnam.

Review of infrared scene projector technology-1993

Science.gov (United States)

Driggers, Ronald G.; Barnard, Kenneth J.; Burroughs, E. E.; Deep, Raymond G.; Williams, Owen M.

1994-07-01

The importance of testing IR imagers and missile seekers with realistic IR scenes warrants a review of the current technologies used in dynamic infrared scene projection. These technologies include resistive arrays, deformable mirror arrays, mirror membrane devices, liquid crystal light valves, laser writers, laser diode arrays, and CRTs. Other methods include frustrated total internal reflection, thermoelectric devices, galvanic cells, Bly cells, and vanadium dioxide. A description of each technology is presented along with a discussion of their relative benefits and disadvantages. The current state of each methodology is also summarized. Finally, the methods are compared and contrasted in terms of their performance parameters.

Use of AFIS for linking scenes of crime.

Science.gov (United States)

Hefetz, Ido; Liptz, Yakir; Vaturi, Shaul; Attias, David

2016-05-01

Forensic intelligence can provide critical information in criminal investigations - the linkage of crime scenes. The Automatic Fingerprint Identification System (AFIS) is an example of a technological improvement that has advanced the entire forensic identification field to strive for new goals and achievements. In one example using AFIS, a series of burglaries into private apartments enabled a fingerprint examiner to search latent prints from different burglary scenes against an unsolved latent print database. Latent finger and palm prints coming from the same source were associated with over than 20 cases. Then, by forensic intelligence and profile analysis the offender's behavior could be anticipated. He was caught, identified, and arrested. It is recommended to perform an AFIS search of LT/UL prints against current crimes automatically as part of laboratory protocol and not by an examiner's discretion. This approach may link different crime scenes. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

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...

Tracking Control of a Magnetic Shape Memory Actuator Using an Inverse Preisach Model with Modified Fuzzy Sliding Mode Control

Directory of Open Access Journals (Sweden)

Jhih-Hong Lin

2016-08-01

Full Text Available Magnetic shape memory (MSM alloys are a new class of smart materials with extraordinary strains up to 12% and frequencies in the range of 1 to 2 kHz. The MSM actuator is a potential device which can achieve high performance electromagnetic actuation by using the properties of MSM alloys. However, significant non-linear hysteresis behavior is a significant barrier to control the MSM actuator. In this paper, the Preisach model was used, by capturing experiments from different input signals and output responses, to model the hysteresis of MSM actuator, and the inverse Preisach model, as a feedforward control, provided compensational signals to the MSM actuator to linearize the hysteresis non-linearity. The control strategy for path tracking combined the hysteresis compensator and the modified fuzzy sliding mode control (MFSMC which served as a path controller. Based on the experimental results, it was verified that a tracking error in the order of micrometers was achieved.

Tracking Control of a Magnetic Shape Memory Actuator Using an Inverse Preisach Model with Modified Fuzzy Sliding Mode Control.

Science.gov (United States)

Lin, Jhih-Hong; Chiang, Mao-Hsiung

2016-08-25

Magnetic shape memory (MSM) alloys are a new class of smart materials with extraordinary strains up to 12% and frequencies in the range of 1 to 2 kHz. The MSM actuator is a potential device which can achieve high performance electromagnetic actuation by using the properties of MSM alloys. However, significant non-linear hysteresis behavior is a significant barrier to control the MSM actuator. In this paper, the Preisach model was used, by capturing experiments from different input signals and output responses, to model the hysteresis of MSM actuator, and the inverse Preisach model, as a feedforward control, provided compensational signals to the MSM actuator to linearize the hysteresis non-linearity. The control strategy for path tracking combined the hysteresis compensator and the modified fuzzy sliding mode control (MFSMC) which served as a path controller. Based on the experimental results, it was verified that a tracking error in the order of micrometers was achieved.

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…

Comparing three cohorts of MSM sampled via sex parties, bars/clubs, and Craigslist.org: implications for researchers and providers.

Science.gov (United States)

Grov, Christian; Rendina, H Jonathon; Parsons, Jeffrey T

2014-08-01

With limited exceptions, few studies have systematically reported on psychosocial and demographic characteristic differences in samples of men who have sex with men (MSM) based on where they were recruited. This study compared three sexually active cohorts of MSM recruited via Craigslist.org (recruited via modified time-space sampling), gay bars and clubs (recruited via time-space sampling), and private sex parties (identified via passive recruitment and listserves), finding mixed results with regard to differences in demographic characteristics, STI history, and psychosocial measures. Men recruited from sex parties were significantly older, reported more symptoms of sexual compulsivity, more likely to be HIV-positive, more likely to report a history of STIs, and more likely to self-identify as a barebacker, than men recruited from the other two venues. In contrast, men from Craigslist.org reported the lowest levels of attachment to the gay and bisexual community and were the least likely to self-identify as gay. Men from bars and clubs were significantly younger, and were more likely to report use of hallucinogens and crack or cocaine. Our findings highlight that the venues in which MSM are recruited have meaningful consequences in terms of the types of individuals who are reached.

A view not to be missed: Salient scene content interferes with cognitive restoration

NARCIS (Netherlands)

van der Jagt, A.P.N.; Craig, Tony; Brewer, Mark J.; Pearson, David G.

2017-01-01

Attention Restoration Theory (ART) states that built scenes place greater load on attentional resources than natural scenes. This is explained in terms of "hard" and "soft" fascination of built and natural scenes. Given a lack of direct empirical evidence for this assumption we propose that

Places in the Brain: Bridging Layout and Object Geometry in Scene-Selective Cortex.

Science.gov (United States)

Dillon, Moira R; Persichetti, Andrew S; Spelke, Elizabeth S; Dilks, Daniel D

2017-06-13

Diverse animal species primarily rely on sense (left-right) and egocentric distance (proximal-distal) when navigating the environment. Recent neuroimaging studies with human adults show that this information is represented in 2 scene-selective cortical regions-the occipital place area (OPA) and retrosplenial complex (RSC)-but not in a third scene-selective region-the parahippocampal place area (PPA). What geometric properties, then, does the PPA represent, and what is its role in scene processing? Here we hypothesize that the PPA represents relative length and angle, the geometric properties classically associated with object recognition, but only in the context of large extended surfaces that compose the layout of a scene. Using functional magnetic resonance imaging adaptation, we found that the PPA is indeed sensitive to relative length and angle changes in pictures of scenes, but not pictures of objects that reliably elicited responses to the same geometric changes in object-selective cortical regions. Moreover, we found that the OPA is also sensitive to such changes, while the RSC is tolerant to such changes. Thus, the geometric information typically associated with object recognition is also used during some aspects of scene processing. These findings provide evidence that scene-selective cortex differentially represents the geometric properties guiding navigation versus scene categorization. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Medial Temporal Lobe Contributions to Episodic Future Thinking: Scene Construction or Future Projection?

Science.gov (United States)

Palombo, D J; Hayes, S M; Peterson, K M; Keane, M M; Verfaellie, M

2018-02-01

Previous research has shown that the medial temporal lobes (MTL) are more strongly engaged when individuals think about the future than about the present, leading to the suggestion that future projection drives MTL engagement. However, future thinking tasks often involve scene processing, leaving open the alternative possibility that scene-construction demands, rather than future projection, are responsible for the MTL differences observed in prior work. This study explores this alternative account. Using functional magnetic resonance imaging, we directly contrasted MTL activity in 1) high scene-construction and low scene-construction imagination conditions matched in future thinking demands and 2) future-oriented and present-oriented imagination conditions matched in scene-construction demands. Consistent with the alternative account, the MTL was more active for the high versus low scene-construction condition. By contrast, MTL differences were not observed when comparing the future versus present conditions. Moreover, the magnitude of MTL activation was associated with the extent to which participants imagined a scene but was not associated with the extent to which participants thought about the future. These findings help disambiguate which component processes of imagination specifically involve the MTL. Published by Oxford University Press 2016.

Dynamical scene analysis with a moving camera: mobile targets detection system

International Nuclear Information System (INIS)

Hennebert, Christine

1996-01-01

This thesis work deals with the detection of moving objects in monocular image sequences acquired with a mobile camera. We propose a method able to detect small moving objects in visible or infrared images of real outdoor scenes. In order to detect objects of very low apparent motion, we consider an analysis on a large temporal interval. We have chosen to compensate for the dominant motion due to the camera displacement for several consecutive images in order to form a sub-sequence of images for which the camera seems virtually static. We have also developed a new approach allowing to extract the different layers of a real scene in order to deal with cases where the 2D motion due to the camera displacement cannot be globally compensated for. To this end, we use a hierarchical model with two levels: the local merging step and the global merging one. Then, an appropriate temporal filtering is applied to registered image sub-sequence to enhance signals corresponding to moving objects. The detection issue is stated as a labeling problem within a statistical regularization based on Markov Random Fields. Our method has been validated on numerous real image sequences depicting complex outdoor scenes. Finally, the feasibility of an integrated circuit for mobile object detection has been proved. This circuit could lead to an ASIC creation. (author) [fr

Affective salience can reverse the effects of stimulus-driven salience on eye movements in complex scenes

Directory of Open Access Journals (Sweden)

Yaqing eNiu

2012-09-01

Full Text Available In natural vision both stimulus features and cognitive/affective factors influence an observer's attention. However, the relationship between stimulus-driven (bottom-up and cognitive/affective (top-down factors remains controversial: Can affective salience counteract strong visual stimulus signals and shift attention allocation irrespective of bottom-up features? Is there any difference between negative and positive scenes in terms of their influence on attention deployment? Here we examined the impact of affective factors on eye movement behavior, to understand the competition between visual stimulus-driven salience and affective salience and how they affect gaze allocation in complex scene viewing. Building on our previous research, we compared predictions generated by a visual salience model with measures indexing participant-identified emotionally meaningful regions of each image. To examine how eye movement behaviour differs for negative, positive, and neutral scenes, we examined the influence of affective salience in capturing attention according to emotional valence. Taken together, our results show that affective salience can override stimulus-driven salience and overall emotional valence can determine attention allocation in complex scenes. These findings are consistent with the hypothesis that cognitive/affective factors play a dominant role in active gaze control.

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

2008-06-01

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 free-viewing condition, and a scene-learning goal (ad memorization), a scene-evaluation goal (ad appreciation), a target-learning goal (product learning), or a target-evaluation goal (product evaluation). The model reflects how attention switches between two states--local and global--expressed in saccades of shorter and longer amplitude on a spatial grid with 48 cells overlaid on the ads. During the 5- to 6-s duration of self-controlled exposure to ads in the magazine context, attention predominantly started in the local state and ended in the global state, and rapidly switched about 5 times between states. The duration of the local attention state was much longer than the duration of the global state. Goals affected the frequency of switching between attention states and the duration of the local, but not of the global, state. (c) 2008 APA, all rights reserved

Robotic Discovery of the Auditory Scene

National Research Council Canada - National Science Library

Martinson, E; Schultz, A

2007-01-01

.... Motivated by the large negative effect of ambient noise sources on robot audition, the long-term goal is to provide awareness of the auditory scene to a robot, so that it may more effectively act...

Developmental Changes in Attention to Faces and Bodies in Static and Dynamic Scenes

Directory of Open Access Journals (Sweden)

Brenda M Stoesz

2014-03-01

Full Text Available Typically developing individuals show a strong visual preference for faces and face-like stimuli; however, this may come at the expense of attending to bodies or to other aspects of a scene. The primary goal of the present study was to provide additional insight into the development of attentional mechanisms that underlie perception of real people in naturalistic scenes. We examined the looking behaviours of typical children, adolescents, and young adults as they viewed static and dynamic scenes depicting one or more people. Overall, participants showed a bias to attend to faces more than on other parts of the scenes. Adding motion cues led to a reduction in the number, but an increase in the average duration of face fixations in single-character scenes. When multiple characters appeared in a scene, motion-related effects were attenuated and participants shifted their gaze from faces to bodies, or made off-screen glances. Children showed the largest effects related to the introduction of motion cues or additional characters, suggesting that they find dynamic faces difficult to process, and are especially prone to look away from faces when viewing complex social scenes – a strategy that could reduce the cognitive and the affective load imposed by having to divide one’s attention between multiple faces. Our findings provide new insights into the typical development of social attention during natural scene viewing, and lay the foundation for future work examining gaze behaviours in typical and atypical development.

Category-length and category-strength effects using images of scenes.

Science.gov (United States)

Baumann, Oliver; Vromen, Joyce M G; Boddy, Adam C; Crawshaw, Eloise; Humphreys, Michael S

2018-06-21

Global matching models have provided an important theoretical framework for recognition memory. Key predictions of this class of models are that (1) increasing the number of occurrences in a study list of some items affects the performance on other items (list-strength effect) and that (2) adding new items results in a deterioration of performance on the other items (list-length effect). Experimental confirmation of these predictions has been difficult, and the results have been inconsistent. A review of the existing literature, however, suggests that robust length and strength effects do occur when sufficiently similar hard-to-label items are used. In an effort to investigate this further, we had participants study lists containing one or more members of visual scene categories (bathrooms, beaches, etc.). Experiments 1 and 2 replicated and extended previous findings showing that the study of additional category members decreased accuracy, providing confirmation of the category-length effect. Experiment 3 showed that repeating some category members decreased the accuracy of nonrepeated members, providing evidence for a category-strength effect. Experiment 4 eliminated a potential challenge to these results. Taken together, these findings provide robust support for global matching models of recognition memory. The overall list lengths, the category sizes, and the number of repetitions used demonstrated that scene categories are well-suited to testing the fundamental assumptions of global matching models. These include (A) interference from memories for similar items and contexts, (B) nondestructive interference, and (C) that conjunctive information is made available through a matching operation.

Amphetamine-Type-Stimulants (ATS) Use and Homosexuality-Related Enacted Stigma Are Associated With Depression Among Men Who Have Sex With Men (MSM) in Two Major Cities in Vietnam in 2014

NARCIS (Netherlands)

Vu, Nga Thi Thu; Holt, Martin; Phan, Huong Thi Thu; La, Lan Thi; Tran, Gioi Minh; Doan, Tung Thanh; Nguyen, Trang Nhu Nguyen; de Wit, John

2017-01-01

BACKGROUND: Men who have sex with men (MSM) are disproportionately affected by mental health concerns, including depression. Amphetamine-type-stimulants (ATS) use and homosexuality-related stigma and discrimination have been found associated with depression among MSM. OBJECTIVES: To assess the

Adaptive attunement of selective covert attention to evolutionary-relevant emotional visual scenes.

Science.gov (United States)

Fernández-Martín, Andrés; Gutiérrez-García, Aída; Capafons, Juan; Calvo, Manuel G

2017-05-01

We investigated selective attention to emotional scenes in peripheral vision, as a function of adaptive relevance of scene affective content for male and female observers. Pairs of emotional-neutral images appeared peripherally-with perceptual stimulus differences controlled-while viewers were fixating on a different stimulus in central vision. Early selective orienting was assessed by the probability of directing the first fixation towards either scene, and the time until first fixation. Emotional scenes selectively captured covert attention even when they were task-irrelevant, thus revealing involuntary, automatic processing. Sex of observers and specific emotional scene content (e.g., male-to-female-aggression, families and babies, etc.) interactively modulated covert attention, depending on adaptive priorities and goals for each sex, both for pleasant and unpleasant content. The attentional system exhibits domain-specific and sex-specific biases and attunements, probably rooted in evolutionary pressures to enhance reproductive and protective success. Emotional cues selectively capture covert attention based on their bio-social significance. Copyright © 2017 Elsevier Inc. All rights reserved.

Adaptive attunement of selective covert attention to evolutionary-relevant emotional visual scenes

OpenAIRE

Fernández-Martín, Andrés (UNIR); Gutiérrez-García, Aida; Capafons, Juan; Calvo, Manuel G

2017-01-01

We investigated selective attention to emotional scenes in peripheral vision, as a function of adaptive relevance of scene affective content for male and female observers. Pairs of emotional neutral images appeared peripherally with perceptual stimulus differences controlled while viewers were fixating on a different stimulus in central vision. Early selective orienting was assessed by the probability of directing the first fixation towards either scene, and the time until first fixation. Emo...

"Bareback" pornography consumption and safe-sex intentions of men having sex with men

NARCIS (Netherlands)

Jonas, K.J.; Hawk, S.T.; Vastenburg, D.; de Groot, P.

2014-01-01

Men having sex with men (MSM) commonly consume "bareback" pornography, which includes scenes of unprotected anal intercourse. Prior research on human imitative behavior suggests that these media might counteract efforts to promote safe-sex behaviors. To date, no studies have demonstrated a causal

Scene recognition and colorization for vehicle infrared images

Science.gov (United States)

Hou, Junjie; Sun, Shaoyuan; Shen, Zhenyi; Huang, Zhen; Zhao, Haitao

2016-10-01

In order to make better use of infrared technology for driving assistance system, a scene recognition and colorization method is proposed in this paper. Various objects in a queried infrared image are detected and labelled with proper categories by a combination of SIFT-Flow and MRF model. The queried image is then colorized by assigning corresponding colors according to the categories of the objects appeared. The results show that the strategy here emphasizes important information of the IR images for human vision and could be used to broaden the application of IR images for vehicle driving.

Data-driven non-Markovian closure models

Science.gov (United States)

Kondrashov, Dmitri; Chekroun, Mickaël D.; Ghil, Michael

2015-03-01

This paper has two interrelated foci: (i) obtaining stable and efficient data-driven closure models by using a multivariate time series of partial observations from a large-dimensional system; and (ii) comparing these closure models with the optimal closures predicted by the Mori-Zwanzig (MZ) formalism of statistical physics. Multilayer stochastic models (MSMs) are introduced as both a generalization and a time-continuous limit of existing multilevel, regression-based approaches to closure in a data-driven setting; these approaches include empirical model reduction (EMR), as well as more recent multi-layer modeling. It is shown that the multilayer structure of MSMs can provide a natural Markov approximation to the generalized Langevin equation (GLE) of the MZ formalism. A simple correlation-based stopping criterion for an EMR-MSM model is derived to assess how well it approximates the GLE solution. Sufficient conditions are derived on the structure of the nonlinear cross-interactions between the constitutive layers of a given MSM to guarantee the existence of a global random attractor. This existence ensures that no blow-up can occur for a broad class of MSM applications, a class that includes non-polynomial predictors and nonlinearities that do not necessarily preserve quadratic energy invariants. The EMR-MSM methodology is first applied to a conceptual, nonlinear, stochastic climate model of coupled slow and fast variables, in which only slow variables are observed. It is shown that the resulting closure model with energy-conserving nonlinearities efficiently captures the main statistical features of the slow variables, even when there is no formal scale separation and the fast variables are quite energetic. Second, an MSM is shown to successfully reproduce the statistics of a partially observed, generalized Lotka-Volterra model of population dynamics in its chaotic regime. The challenges here include the rarity of strange attractors in the model's parameter

Sexual risk taking in relation to sexual identification, age, and education in a diverse sample of African American men who have sex with men (MSM) in New York City.

Science.gov (United States)

Hampton, Melvin C; Halkitis, Perry N; Storholm, Erik D; Kupprat, Sandra A; Siconolfi, Daniel E; Jones, Donovan; Steen, Jeff T; Gillen, Sara; McCree, Donna Hubbard

2013-03-01

HIV disproportionately affects African American men who have sex with men (MSM) in the United States. To inform this epidemiological pattern, we examined cross-sectional sexual behavior data in 509 African American MSM. Bivariate logistic regression analyses were conducted to examine the extent to which age, education,and sexual identity explain the likelihood of engaging in sex with a partner of a specific gender and the likelihood of engaging in unprotected sexual behaviors based on partner gender. Across all partner gender types,unprotected sexual behaviors were more likely to be reported by men with lower education. Younger, non-gay identified men were more likely to engage in unprotected sexual behaviors with transgender partners, while older, non-gay identified men were more likely to engage in unprotected sexual behaviors with women. African American MSM do not represent a monolithic group in their sexual behaviors, highlighting the need to target HIV prevention efforts to different subsets of African American MSM communities as appropriate.

Automating the construction of scene classifiers for content-based video retrieval

NARCIS (Netherlands)

Khan, L.; Israël, Menno; Petrushin, V.A.; van den Broek, Egon; van der Putten, Peter

2004-01-01

This paper introduces a real time automatic scene classifier within content-based video retrieval. In our envisioned approach end users like documentalists, not image processing experts, build classifiers interactively, by simply indicating positive examples of a scene. Classification consists of a

Motives and barriers to safer sex and regular STI testing among MSM soon after HIV diagnosis

NARCIS (Netherlands)

Heijman, Titia; Zuure, Freke; Stolte, Ineke; Davidovich, Udi

2017-01-01

Understanding why some recently with HIV diagnosed men who have sex with men (MSM) choose for safer sex and regular STI testing, whereas others do not, is important for the development of interventions that aim to improve the sexual health of those newly infected. To gain insight into motives and

Number of perceptually distinct surface colors in natural scenes.

Science.gov (United States)

Marín-Franch, Iván; Foster, David H

2010-09-30

The ability to perceptually identify distinct surfaces in natural scenes by virtue of their color depends not only on the relative frequency of surface colors but also on the probabilistic nature of observer judgments. Previous methods of estimating the number of discriminable surface colors, whether based on theoretical color gamuts or recorded from real scenes, have taken a deterministic approach. Thus, a three-dimensional representation of the gamut of colors is divided into elementary cells or points which are spaced at one discrimination-threshold unit intervals and which are then counted. In this study, information-theoretic methods were used to take into account both differing surface-color frequencies and observer response uncertainty. Spectral radiances were calculated from 50 hyperspectral images of natural scenes and were represented in a perceptually almost uniform color space. The average number of perceptually distinct surface colors was estimated as 7.3 × 10(3), much smaller than that based on counting methods. This number is also much smaller than the number of distinct points in a scene that are, in principle, available for reliable identification under illuminant changes, suggesting that color constancy, or the lack of it, does not generally determine the limit on the use of color for surface identification.

Characteristics of nontrauma scene flights for air medical transport.

Science.gov (United States)

Krebs, Margaret G; Fletcher, Erica N; Werman, Howard; McKenzie, Lara B

2014-01-01

Little is known about the use of air medical transport for patients with medical, rather than traumatic, emergencies. This study describes the practices of air transport programs, with respect to nontrauma scene responses, in several areas throughout the United States and Canada. A descriptive, retrospective study was conducted of all nontrauma scene flights from 2008 and 2009. Flight information and patient demographic data were collected from 5 air transport programs. Descriptive statistics were used to examine indications for transport, Glasgow Coma Scale Scores, and loaded miles traveled. A total of 1,785 nontrauma scene flights were evaluated. The percentage of scene flights contributed by nontraumatic emergencies varied between programs, ranging from 0% to 44.3%. The most common indication for transport was cardiac, nonST-segment elevation myocardial infarction (22.9%). Cardiac arrest was the indication for transport in 2.5% of flights. One air transport program reported a high percentage (49.4) of neurologic, stroke, flights. The use of air transport for nontraumatic emergencies varied considerably between various air transport programs and regions. More research is needed to evaluate which nontraumatic emergencies benefit from air transport. National guidelines regarding the use of air transport for nontraumatic emergencies are needed. Copyright © 2014 Air Medical Journal Associates. Published by Elsevier Inc. All rights reserved.

Data-based Non-Markovian Model Inference

Science.gov (United States)

Ghil, Michael

2015-04-01

This talk concentrates on obtaining stable and efficient data-based models for simulation and prediction in the geosciences and life sciences. The proposed model derivation relies on using a multivariate time series of partial observations from a large-dimensional system, and the resulting low-order models are compared with the optimal closures predicted by the non-Markovian Mori-Zwanzig formalism of statistical physics. Multilayer stochastic models (MSMs) are introduced as both a very broad generalization and a time-continuous limit of existing multilevel, regression-based approaches to data-based closure, in particular of empirical model reduction (EMR). We show that the multilayer structure of MSMs can provide a natural Markov approximation to the generalized Langevin equation (GLE) of the Mori-Zwanzig formalism. A simple correlation-based stopping criterion for an EMR-MSM model is derived to assess how well it approximates the GLE solution. Sufficient conditions are given for the nonlinear cross-interactions between the constitutive layers of a given MSM to guarantee the existence of a global random attractor. This existence ensures that no blow-up can occur for a very broad class of MSM applications. The EMR-MSM methodology is first applied to a conceptual, nonlinear, stochastic climate model of coupled slow and fast variables, in which only slow variables are observed. The resulting reduced model with energy-conserving nonlinearities captures the main statistical features of the slow variables, even when there is no formal scale separation and the fast variables are quite energetic. Second, an MSM is shown to successfully reproduce the statistics of a partially observed, generalized Lokta-Volterra model of population dynamics in its chaotic regime. The positivity constraint on the solutions' components replaces here the quadratic-energy-preserving constraint of fluid-flow problems and it successfully prevents blow-up. This work is based on a close

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.

STREAM PROCESSING ALGORITHMS FOR DYNAMIC 3D SCENE ANALYSIS

Science.gov (United States)

2018-02-15

PROCESSING ALGORITHMS FOR DYNAMIC 3D SCENE ANALYSIS 5a. CONTRACT NUMBER FA8750-14-2-0072 5b. GRANT NUMBER N/A 5c. PROGRAM ELEMENT NUMBER 62788F 6...of Figures 1 The 3D processing pipeline flowchart showing key modules. . . . . . . . . . . . . . . . . 12 2 Overall view (data flow) of the proposed...pipeline flowchart showing key modules. from motion and bundle adjustment algorithm. By fusion of depth masks of the scene obtained from 3D

Children's Development of Analogical Reasoning: Insights from Scene Analogy Problems

Science.gov (United States)

Richland, Lindsey E.; Morrison, Robert G.; Holyoak, Keith J.

2006-01-01

We explored how relational complexity and featural distraction, as varied in scene analogy problems, affect children's analogical reasoning performance. Results with 3- and 4-year-olds, 6- and 7-year-olds, 9- to 11-year-olds, and 13- and 14-year-olds indicate that when children can identify the critical structural relations in a scene analogy…

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…

Emotional event-related potentials are larger to figures than scenes but are similarly reduced by inattention

Directory of Open Access Journals (Sweden)

Nordström Henrik

2012-05-01

Full Text Available Abstract Background In research on event-related potentials (ERP to emotional pictures, greater attention to emotional than neutral stimuli (i.e., motivated attention is commonly indexed by two difference waves between emotional and neutral stimuli: the early posterior negativity (EPN and the late positive potential (LPP. Evidence suggests that if attention is directed away from the pictures, then the emotional effects on EPN and LPP are eliminated. However, a few studies have found residual, emotional effects on EPN and LPP. In these studies, pictures were shown at fixation, and picture composition was that of simple figures rather than that of complex scenes. Because figures elicit larger LPP than do scenes, figures might capture and hold attention more strongly than do scenes. Here, we showed negative and neutral pictures of figures and scenes and tested first, whether emotional effects are larger to figures than scenes for both EPN and LPP, and second, whether emotional effects on EPN and LPP are reduced less for unattended figures than scenes. Results Emotional effects on EPN and LPP were larger for figures than scenes. When pictures were unattended, emotional effects on EPN increased for scenes but tended to decrease for figures, whereas emotional effects on LPP decreased similarly for figures and scenes. Conclusions Emotional effects on EPN and LPP were larger for figures than scenes, but these effects did not resist manipulations of attention more strongly for figures than scenes. These findings imply that the emotional content captures attention more strongly for figures than scenes, but that the emotional content does not hold attention more strongly for figures than scenes.

Emotional event-related potentials are larger to figures than scenes but are similarly reduced by inattention

Science.gov (United States)

2012-01-01

Background In research on event-related potentials (ERP) to emotional pictures, greater attention to emotional than neutral stimuli (i.e., motivated attention) is commonly indexed by two difference waves between emotional and neutral stimuli: the early posterior negativity (EPN) and the late positive potential (LPP). Evidence suggests that if attention is directed away from the pictures, then the emotional effects on EPN and LPP are eliminated. However, a few studies have found residual, emotional effects on EPN and LPP. In these studies, pictures were shown at fixation, and picture composition was that of simple figures rather than that of complex scenes. Because figures elicit larger LPP than do scenes, figures might capture and hold attention more strongly than do scenes. Here, we showed negative and neutral pictures of figures and scenes and tested first, whether emotional effects are larger to figures than scenes for both EPN and LPP, and second, whether emotional effects on EPN and LPP are reduced less for unattended figures than scenes. Results Emotional effects on EPN and LPP were larger for figures than scenes. When pictures were unattended, emotional effects on EPN increased for scenes but tended to decrease for figures, whereas emotional effects on LPP decreased similarly for figures and scenes. Conclusions Emotional effects on EPN and LPP were larger for figures than scenes, but these effects did not resist manipulations of attention more strongly for figures than scenes. These findings imply that the emotional content captures attention more strongly for figures than scenes, but that the emotional content does not hold attention more strongly for figures than scenes. PMID:22607397

Application of the Modified Source Multiplication (MSM) technique to subcritical reactivity worth measurements in thermal and fast reactor systems

International Nuclear Information System (INIS)

Blaise, P.; Fougeras, P.; Mellier, F.

2009-01-01

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. They have been successfully applied to absorber (single or clusters) worth measurement in both thermal and fast spectra, or for (sodium or water) void reactivity worths. The ASM methodology, which is the basic technique to estimate a reactivity worth, uses relatively simple relationships between count rates of efficient miniature fission chambers located in slightly subcritical reference and perturbed configurations. If this method works quite well for small reactivity variation (a few effective delayed neutron fraction), its raw results needs to be corrected to take into account the flux perturbation in the fission chamber. This is performed by applying to the measurement a correction factor called MSM. Its characteristics is to take into account the local space and energy variation of the spectrum in the fission chamber, through standard perturbation theory applied to neutron transport calculation in the perturbed configuration. The proposed paper describes in details 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 data. (authors)

Short report: the effect of expertise in hiking on recognition memory for mountain scenes.

Science.gov (United States)

Kawamura, Satoru; Suzuki, Sae; Morikawa, Kazunori

2007-10-01

The nature of an expert memory advantage that does not depend on stimulus structure or chunking was examined, using more ecologically valid stimuli in the context of a more natural activity than previously studied domains. Do expert hikers and novice hikers see and remember mountain scenes differently? In the present experiment, 18 novice hikers and 17 expert hikers were presented with 60 photographs of scenes from hiking trails. These scenes differed in the degree of functional aspects that implied some action possibilities or dangers. The recognition test revealed that the memory performance of experts was significantly superior to that of novices for scenes with highly functional aspects. The memory performance for the scenes with few functional aspects did not differ between novices and experts. These results suggest that experts pay more attention to, and thus remember better, scenes with functional meanings than do novices.

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.

The Anthropo-scene: A guide for the perplexed.

Science.gov (United States)

Lorimer, Jamie

2017-02-01

The scientific proposal that the Earth has entered a new epoch as a result of human activities - the Anthropocene - has catalysed a flurry of intellectual activity. I introduce and review the rich, inchoate and multi-disciplinary diversity of this Anthropo-scene. I identify five ways in which the concept of the Anthropocene has been mobilized: scientific question, intellectual zeitgeist, ideological provocation, new ontologies and science fiction. This typology offers an analytical framework for parsing this diversity, for understanding the interactions between different ways of thinking in the Anthropo-scene, and thus for comprehending elements of its particular and peculiar sociabilities. Here I deploy this framework to situate Earth Systems Science within the Anthropo-scene, exploring both the status afforded science in discussions of this new epoch, and the various ways in which the other means of engaging with the concept come to shape the conduct, content and politics of this scientific enquiry. In conclusion the paper reflects on the potential of the Anthropocene for new modes of academic praxis.

A Virtual Environments Editor for Driving Scenes

Directory of Open Access Journals (Sweden)

Ronald R. Mourant

2003-12-01

Full Text Available The goal of this project was to enable the rapid creation of three-dimensional virtual driving environments. We designed and implemented a high-level scene editor that allows a user to construct a driving environment by pasting icons that represent 1 road segments, 2 road signs, 3 trees and 4 buildings. These icons represent two- and three-dimensional objects that have been predesigned. Icons can be placed in the scene at specific locations (x, y, and z coordinates. The editor includes the capability of a user to "drive" a vehicle using a computer mouse for steering, accelerating and braking. At any time during the process of building a virtual environment, a user may switch to "Run Mode" and inspect the three-dimensional scene by "driving" through it using the mouse. Adjustments and additions can be made to the virtual environment by going back to "Build Mode". Once a user is satisfied with the threedimensional virtual environment, it can be saved in a file. The file can used with Java3D software that enables the traversing of three-dimensional environments. The process of building virtual environments from predesigned icons can be applied to many other application areas. It will enable novice computer users to rapidly construct and use three-dimensional virtual environments.

Where and when Do Objects Become Scenes?

Directory of Open Access Journals (Sweden)

Jiye G. Kim

2011-05-01

Full Text Available Scenes can be understood with extraordinary speed and facility, not merely as an inventory of individual objects but in the coding of the relations among them. These relations, which can be readily described by prepositions or gerunds (e.g., a hand holding a pen, allows the explicit representation of complex structures. Where in the brain are inter-object relations specified? In a series of fMRI experiments, we show that pairs of objects shown as interacting elicit greater activity in LOC than when the objects are depicted side-by-side (e.g., a hand beside a pen. Other visual areas, PPA, IPS, and DLPFC, did not show this sensitivity to scene relations, rendering it unlikely that the relations were computed in these regions. Using EEG and TMS, we further show that LOC's sensitivity to object interactions arises around 170ms post stimulus onset and that disruption of normal LOC activity—but not IPS activity—is detrimental to the behavioral sensitivity of inter-object relations. Insofar as LOC is the earliest cortical region where shape is distinguished from texture, our results provide strong evidence that scene-like relations are achieved simultaneously with the perception of object shape and not inferred at some stage following object identification.

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

Science.gov (United States)

2012-09-01

its effect on the optical beam. Computer Tunable optical source Detectors Test MSM detector Lock-in- amplifier Multiplexer Transimpedance ... amplifier Three-way beam splitter L3 sample L1 Light source L4 L2 Reference Detector Reflectance Detector

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.

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.

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.

Single-View 3D Scene Reconstruction and Parsing by Attribute Grammar.

Science.gov (United States)

Liu, Xiaobai; Zhao, Yibiao; Zhu, Song-Chun

2018-03-01

In this paper, we present an attribute grammar for solving two coupled tasks: i) parsing a 2D image into semantic regions; and ii) recovering the 3D scene structures of all regions. The proposed grammar consists of a set of production rules, each describing a kind of spatial relation between planar surfaces in 3D scenes. These production rules are used to decompose an input image into a hierarchical parse graph representation where each graph node indicates a planar surface or a composite surface. Different from other stochastic image grammars, the proposed grammar augments each graph node with a set of attribute variables to depict scene-level global geometry, e.g., camera focal length, or local geometry, e.g., surface normal, contact lines between surfaces. These geometric attributes impose constraints between a node and its off-springs in the parse graph. Under a probabilistic framework, we develop a Markov Chain Monte Carlo method to construct a parse graph that optimizes the 2D image recognition and 3D scene reconstruction purposes simultaneously. We evaluated our method on both public benchmarks and newly collected datasets. Experiments demonstrate that the proposed method is capable of achieving state-of-the-art scene reconstruction of a single image.

Effects of scene content and layout on the perceived light direction in 3D spaces.

Science.gov (United States)

Xia, Ling; Pont, Sylvia C; Heynderickx, Ingrid

2016-08-01

The lighting and furnishing of an interior space (i.e., the reflectance of its materials, the geometries of the furnishings, and their arrangement) determine the appearance of this space. Conversely, human observers infer lighting properties from the space's appearance. We conducted two psychophysical experiments to investigate how the perception of the light direction is influenced by a scene's objects and their layout using real scenes. In the first experiment, we confirmed that the shape of the objects in the scene and the scene layout influence the perceived light direction. In the second experiment, we systematically investigated how specific shape properties influenced the estimation of the light direction. The results showed that increasing the number of visible faces of an object, ultimately using globally spherical shapes in the scene, supported the veridicality of the estimated light direction. Furthermore, symmetric arrangements in the scene improved the estimation of the tilt direction. Thus, human perception of light should integrally consider materials, scene content, and layout.

Neural Correlates of Divided Attention in Natural Scenes.

Science.gov (United States)

Fagioli, Sabrina; Macaluso, Emiliano

2016-09-01

Individuals are able to split attention between separate locations, but divided spatial attention incurs the additional requirement of monitoring multiple streams of information. Here, we investigated divided attention using photos of natural scenes, where the rapid categorization of familiar objects and prior knowledge about the likely positions of objects in the real world might affect the interplay between these spatial and nonspatial factors. Sixteen participants underwent fMRI during an object detection task. They were presented with scenes containing either a person or a car, located on the left or right side of the photo. Participants monitored either one or both object categories, in one or both visual hemifields. First, we investigated the interplay between spatial and nonspatial attention by comparing conditions of divided attention between categories and/or locations. We then assessed the contribution of top-down processes versus stimulus-driven signals by separately testing the effects of divided attention in target and nontarget trials. The results revealed activation of a bilateral frontoparietal network when dividing attention between the two object categories versus attending to a single category but no main effect of dividing attention between spatial locations. Within this network, the left dorsal premotor cortex and the left intraparietal sulcus were found to combine task- and stimulus-related signals. These regions showed maximal activation when participants monitored two categories at spatially separate locations and the scene included a nontarget object. We conclude that the dorsal frontoparietal cortex integrates top-down and bottom-up signals in the presence of distractors during divided attention in real-world scenes.

Gist in time: Scene semantics and structure enhance recall of searched objects.

Science.gov (United States)

Josephs, Emilie L; Draschkow, Dejan; Wolfe, Jeremy M; Võ, Melissa L-H

2016-09-01

Previous work has shown that recall of objects that are incidentally encountered as targets in visual search is better than recall of objects that have been intentionally memorized (Draschkow, Wolfe, & Võ, 2014). However, this counter-intuitive result is not seen when these tasks are performed with non-scene stimuli. The goal of the current paper is to determine what features of search in a scene contribute to higher recall rates when compared to a memorization task. In each of four experiments, we compare the free recall rate for target objects following a search to the rate following a memorization task. Across the experiments, the stimuli include progressively more scene-related information. Experiment 1 provides the spatial relations between objects. Experiment 2 adds relative size and depth of objects. Experiments 3 and 4 include scene layout and semantic information. We find that search leads to better recall than explicit memorization in cases where scene layout and semantic information are present, as long as the participant has ample time (2500ms) to integrate this information with knowledge about the target object (Exp. 4). These results suggest that the integration of scene and target information not only leads to more efficient search, but can also contribute to stronger memory representations than intentional memorization. Copyright © 2016 Elsevier B.V. All rights reserved.

The development of brain systems associated with successful memory retrieval of scenes.

Science.gov (United States)

Ofen, Noa; Chai, Xiaoqian J; Schuil, Karen D I; Whitfield-Gabrieli, Susan; Gabrieli, John D E

2012-07-18

Neuroanatomical and psychological evidence suggests prolonged maturation of declarative memory systems in the human brain from childhood into young adulthood. Here, we examine functional brain development during successful memory retrieval of scenes in children, adolescents, and young adults ages 8-21 via functional magnetic resonance imaging. Recognition memory improved with age, specifically for accurate identification of studied scenes (hits). Successful retrieval (correct old-new decisions for studied vs unstudied scenes) was associated with activations in frontal, parietal, and medial temporal lobe (MTL) regions. Activations associated with successful retrieval increased with age in left parietal cortex (BA7), bilateral prefrontal, and bilateral caudate regions. In contrast, activations associated with successful retrieval did not change with age in the MTL. Psychophysiological interaction analysis revealed that there were, however, age-relate changes in differential connectivity for successful retrieval between MTL and prefrontal regions. These results suggest that neocortical regions related to attentional or strategic control show the greatest developmental changes for memory retrieval of scenes. Furthermore, these results suggest that functional interactions between MTL and prefrontal regions during memory retrieval also develop into young adulthood. The developmental increase of memory-related activations in frontal and parietal regions for retrieval of scenes and the absence of such an increase in MTL regions parallels what has been observed for memory encoding of scenes.

Image Chunking: Defining Spatial Building Blocks for Scene Analysis.

Science.gov (United States)

1987-04-01

mumgs0.USmusa 7.AUWOJO 4. CIUTAC Rm6ANT Wuugme*j James V/. Mlahoney DACA? 6-85-C-00 10 NOQ 1 4-85-K-O 124 Artificial Inteligence Laboratory US USS 545...0197 672 IMAGE CHUWING: DEINING SPATIAL UILDING PLOCKS FOR 142 SCENE ANRLYSIS(U) MASSACHUSETTS INST OF TECH CAIIAIDGE ARTIFICIAL INTELLIGENCE LAO J...Technical Report 980 F-Image Chunking: Defining Spatial Building Blocks for Scene DTm -Analysis S ELECTED James V. Mahoney’ MIT Artificial Intelligence

Analysis of the crime scene model using three objects from the collection of the Hans Gross Museum of Criminology of the University of Graz.

Science.gov (United States)

Elek, Lydia

2016-01-01

As part of the collection in the Hans Gross Museum of Criminology in Graz there are still three crime scene reliefs; two of which were made by Hans Gross himself. The practical purpose of these criminal landscape models is something one could speculate about, but such models may have been useful in two fields: in the criminal lab and in the courtroom. To see the reliefs in a scientific experimental context as well as under the aspects of artwork and topography is as essential as emphasizing their genuine military character.

Neural representation of anxiety and personality during exposure to anxiety-provoking and neutral scenes from scary movies.

Science.gov (United States)

Straube, Thomas; Preissler, Sandra; Lipka, Judith; Hewig, Johannes; Mentzel, Hans-Joachim; Miltner, Wolfgang H R

2010-01-01

Some people search for intense sensations such as being scared by frightening movies while others do not. The brain mechanisms underlying such inter-individual differences are not clear. Testing theoretical models, we investigated neural correlates of anxiety and the personality trait sensation seeking in 40 subjects who watched threatening and neutral scenes from scary movies during functional magnetic resonance imaging. Threat versus neutral scenes induced increased activation in anterior cingulate cortex, insula, thalamus, and visual areas. Movie-induced anxiety correlated positively with activation in dorsomedial prefrontal cortex, indicating a role for this area in the subjective experience of being scared. Sensation seeking-scores correlated positively with brain activation to threat versus neutral scenes in visual areas and in thalamus and anterior insula, i.e. regions involved in the induction and representation of arousal states. For the insula and thalamus, these outcomes were partly due to an inverse relation between sensation seeking scores and brain activation during neutral film clips. These results support models predicting cerebral hypoactivation in high sensation seekers during neutral stimulation, which may be compensated by more intense sensations such as watching scary movies. 2009 Wiley-Liss, Inc.

Global Transsaccadic Change Blindness During Scene Perception

National Research Council Canada - National Science Library

Henderson, John

2003-01-01

.... The results from two experiments demonstrated a global transsaccadic change-blindness effect, suggesting that point-by-point visual representations are not functional across saccades during complex scene perception. Ahstract.

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.

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.

Lymphogranuloma venereum in an Italian MSM: concurrent pharyngeal and rectal infection.

Science.gov (United States)

Foschi, Claudio; Filippini, Andrea; D'Antuono, Antonietta; Compri, Monica; Macca, Francesca; Banzola, Nicoletta; Marangoni, Antonella

2014-07-01

An Italian HIV-positive man having sex with men (MSM) attended the STIs Outpatients Clinic of Sant'Orsola Hospital in Bologna complaining of anal pain and constipation. According to patient's sexual history and repertoires, NAAT testing for Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (GC) was performed. Pharyngeal and anal swabs resulted positive for CT DNA detection and the following molecular genotyping identified a L2 serovar, coming to the final diagnosis of pharyngeal and rectal lymphogranuloma venereum (LGV) infection. After an antibiotic therapy with doxycycline 100 mg twice a day for 3 weeks, the patient completely recovered and the test of cure was negative for LGV infection.

Preparedness for use of the rapid result HIV self-test by gay men and other men who have sex with men (MSM): a mixed methods exploratory study among MSM and those involved in HIV prevention and care.

Science.gov (United States)

Flowers, P; Riddell, J; Park, C; Ahmed, B; Young, I; Frankis, J; Davis, M; Gilbert, M; Estcourt, C; Wallace, L; McDaid, L M

2017-04-01

The aim of the study was to explore preparedness for the HIV self-test among men who have sex with men (MSM) and those involved in HIV prevention and care. A mixed methods exploratory research design was employed, detailing awareness and willingness to use the self-test and the perceived barriers and facilitators to implementation. Quantitative and qualitative data collection and analysis were completed in parallel. Descriptive and inferential analysis of cross-sectional bar-based survey data collected from MSM through a self-completed questionnaire and oral fluid specimen collection (n = 999) was combined with qualitative, thematic, analysis of data collected through 12 expert focus groups (n = 55) consisting of gay men, National Health Service (NHS) staff, community organizations, entrepreneurs and activists. Findings were subsequently combined and assessed for synergies. Among MSM, self-test awareness was moderate (55%). Greater awareness was associated with increased educational attainment [adjusted odds ratio 1.51; 95% confidence interval (CI) 1.00-2.30; P = 0.05] and previous history of sexually transmitted infection (STI) testing (adjusted odds ratio 1.63; 95% CI 1.11-2.39; P = 0.01). Willingness to use the test was high (89%) and associated with meeting sexual partners online (unadjusted odds ratio 1.96; 95% CI 1.31-2.94; P self-testing; it was understood as convenient, discreet, accessible, and with a low burden to services. However, some ambivalence towards self-testing was reported; it could reduce opportunities to engage with wider services, wider health issues and the determinants of risk. Self-testing represents an opportunity to reduce barriers to HIV testing and enhance prevention and access to care. Levels of awareness are moderate but willingness to use is high. Self-testing may amplify health inequalities. © 2016 The Authors. HIV Medicine published by John Wiley & Sons Ltd on behalf of British HIV Association.

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.

Guidance of Attention to Objects and Locations by Long-Term Memory of Natural Scenes

Science.gov (United States)

Becker, Mark W.; Rasmussen, Ian P.

2008-01-01

Four flicker change-detection experiments demonstrate that scene-specific long-term memory guides attention to both behaviorally relevant locations and objects within a familiar scene. Participants performed an initial block of change-detection trials, detecting the addition of an object to a natural scene. After a 30-min delay, participants…

Generation of binary holograms for deep scenes captured with a camera and a depth sensor

Science.gov (United States)

Leportier, Thibault; Park, Min-Chul

2017-01-01

This work presents binary hologram generation from images of a real object acquired from a Kinect sensor. Since hologram calculation from a point-cloud or polygon model presents a heavy computational burden, we adopted a depth-layer approach to generate the holograms. This method enables us to obtain holographic data of large scenes quickly. Our investigations focus on the performance of different methods, iterative and noniterative, to convert complex holograms into binary format. Comparisons were performed to examine the reconstruction of the binary holograms at different depths. We also propose to modify the direct binary search algorithm to take into account several reference image planes. Then, deep scenes featuring multiple planes of interest can be reconstructed with better efficiency.

Semantic memory for contextual regularities within and across scene categories: evidence from eye movements.

Science.gov (United States)

Brockmole, James R; Le-Hoa Võ, Melissa

2010-10-01

When encountering familiar scenes, observers can use item-specific memory to facilitate the guidance of attention to objects appearing in known locations or configurations. Here, we investigated how memory for relational contingencies that emerge across different scenes can be exploited to guide attention. Participants searched for letter targets embedded in pictures of bedrooms. In a between-subjects manipulation, targets were either always on a bed pillow or randomly positioned. When targets were systematically located within scenes, search for targets became more efficient. Importantly, this learning transferred to bedrooms without pillows, ruling out learning that is based on perceptual contingencies. Learning also transferred to living room scenes, but it did not transfer to kitchen scenes, even though both scene types contained pillows. These results suggest that statistical regularities abstracted across a range of stimuli are governed by semantic expectations regarding the presence of target-predicting local landmarks. Moreover, explicit awareness of these contingencies led to a central tendency bias in recall memory for precise target positions that is similar to the spatial category effects observed in landmark memory. These results broaden the scope of conditions under which contextual cuing operates and demonstrate how semantic memory plays a causal and independent role in the learning of associations between objects in real-world scenes.

The elephant in the room: Inconsistency in scene viewing and representation.

Science.gov (United States)

Spotorno, Sara; Tatler, Benjamin W

2017-10-01

We examined the extent to which semantic informativeness, consistency with expectations and perceptual salience contribute to object prioritization in scene viewing and representation. In scene viewing (Experiments 1-2), semantic guidance overshadowed perceptual guidance in determining fixation order, with the greatest prioritization for objects that were diagnostic of the scene's depicted event. Perceptual properties affected selection of consistent objects (regardless of their informativeness) but not of inconsistent objects. Semantic and perceptual properties also interacted in influencing foveal inspection, as inconsistent objects were fixated longer than low but not high salience diagnostic objects. While not studied in direct competition with each other (each studied in competition with diagnostic objects), we found that inconsistent objects were fixated earlier and for longer than consistent but marginally informative objects. In change detection (Experiment 3), perceptual guidance overshadowed semantic guidance, promoting detection of highly salient changes. A residual advantage for diagnosticity over inconsistency emerged only when selection prioritization could not be based on low-level features. Overall these findings show that semantic inconsistency is not prioritized within a scene when competing with other relevant information that is essential to scene understanding and respects observers' expectations. Moreover, they reveal that the relative dominance of semantic or perceptual properties during selection depends on ongoing task requirements. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Fuzzy Classification of High Resolution Remote Sensing Scenes Using Visual Attention Features

Directory of Open Access Journals (Sweden)

Linyi Li

2017-01-01

Full Text Available In recent years the spatial resolutions of remote sensing images have been improved greatly. However, a higher spatial resolution image does not always lead to a better result of automatic scene classification. Visual attention is an important characteristic of the human visual system, which can effectively help to classify remote sensing scenes. In this study, a novel visual attention feature extraction algorithm was proposed, which extracted visual attention features through a multiscale process. And a fuzzy classification method using visual attention features (FC-VAF was developed to perform high resolution remote sensing scene classification. FC-VAF was evaluated by using remote sensing scenes from widely used high resolution remote sensing images, including IKONOS, QuickBird, and ZY-3 images. FC-VAF achieved more accurate classification results than the others according to the quantitative accuracy evaluation indices. We also discussed the role and impacts of different decomposition levels and different wavelets on the classification accuracy. FC-VAF improves the accuracy of high resolution scene classification and therefore advances the research of digital image analysis and the applications of high resolution remote sensing images.

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…

A methodological framework for detecting ulcers' risk in diabetic foot subjects by combining gait analysis, a new musculoskeletal foot model and a foot finite element model.

Science.gov (United States)

Scarton, Alessandra; Guiotto, Annamaria; Malaquias, Tiago; Spolaor, Fabiola; Sinigaglia, Giacomo; Cobelli, Claudio; Jonkers, Ilse; Sawacha, Zimi

2018-02-01

Diabetic foot is one of the most debilitating complications of diabetes and may lead to plantar ulcers. In the last decade, gait analysis, musculoskeletal modelling (MSM) and finite element modelling (FEM) have shown their ability to contribute to diabetic foot prevention and suggested that the origin of the plantar ulcers is in deeper tissue layers rather than on the plantar surface. Hence the aim of the current work is to develop a methodology that improves FEM-derived foot internal stresses prediction, for diabetic foot prevention applications. A 3D foot FEM was combined with MSM derived force to predict the sites of excessive internal stresses on the foot. In vivo gait analysis data, and an MRI scan of a foot from a healthy subject were acquired and used to develop a six degrees of freedom (6 DOF) foot MSM and a 3D subject-specific foot FEM. Ankle kinematics were applied as boundary conditions to the FEM together with: 1. only Ground Reaction Forces (GRFs); 2. OpenSim derived extrinsic muscles forces estimated with a standard OpenSim MSM; 3. extrinsic muscle forces derived through the (6 DOF) foot MSM; 4. intrinsic and extrinsic muscles forces derived through the 6 DOF foot MSM. For model validation purposes, simulated peak pressures were extracted and compared with those measured experimentally. The importance of foot muscles in controlling plantar pressure distribution and internal stresses is confirmed by the improved accuracy in the estimation of the peak pressures obtained with the inclusion of intrinsic and extrinsic muscle forces. Copyright © 2017 Elsevier B.V. All rights reserved.

Smoking scenes in popular Japanese serial television dramas: descriptive analysis during the same 3-month period in two consecutive years.

Science.gov (United States)

Kanda, Hideyuki; Okamura, Tomonori; Turin, Tanvir Chowdhury; Hayakawa, Takehito; Kadowaki, Takashi; Ueshima, Hirotsugu

2006-06-01

Japanese serial television dramas are becoming very popular overseas, particularly in other Asian countries. Exposure to smoking scenes in movies and television dramas has been known to trigger initiation of habitual smoking in young people. Smoking scenes in Japanese dramas may affect the smoking behavior of many young Asians. We examined smoking scenes and smoking-related items in serial television dramas targeting young audiences in Japan during the same season in two consecutive years. Fourteen television dramas targeting the young audience broadcast between July and September in 2001 and 2002 were analyzed. A total of 136 h 42 min of television programs were divided into unit scenes of 3 min (a total of 2734 unit scenes). All the unit scenes were reviewed for smoking scenes and smoking-related items. Of the 2734 3-min unit scenes, 205 (7.5%) were actual smoking scenes and 387 (14.2%) depicted smoking environments with the presence of smoking-related items, such as ash trays. In 185 unit scenes (90.2% of total smoking scenes), actors were shown smoking. Actresses were less frequently shown smoking (9.8% of total smoking scenes). Smoking characters in dramas were in the 20-49 age group in 193 unit scenes (94.1% of total smoking scenes). In 96 unit scenes (46.8% of total smoking scenes), at least one non-smoker was present in the smoking scenes. The smoking locations were mainly indoors, including offices, restaurants and homes (122 unit scenes, 59.6%). The most common smoking-related items shown were ash trays (in 45.5% of smoking-item-related scenes) and cigarettes (in 30.2% of smoking-item-related scenes). Only 3 unit scenes (0.1 % of all scenes) promoted smoking prohibition. This was a descriptive study to examine the nature of smoking scenes observed in Japanese television dramas from a public health perspective.

Technicolor/INRIA team at the MediaEval 2013 Violent Scenes Detection Task

OpenAIRE

Penet , Cédric; Demarty , Claire-Hélène; Gravier , Guillaume; Gros , Patrick

2013-01-01

International audience; This paper presents the work done at Technicolor and INRIA regarding the MediaEval 2013 Violent Scenes Detection task, which aims at detecting violent scenes in movies. We participated in both the objective and the subjective subtasks.

?The Devil has entered you?: A qualitative study of Men Who Have Sex With Men (MSM) and the stigma and discrimination they experience from healthcare professionals and the general community in Bosnia and Herzegovina

OpenAIRE

Stojisavljevic, Stela; Djikanovic, Bosiljka; Matejic, Bojana

2017-01-01

Men who have sex with men (MSM) are often exposed to unequal treatment in societies worldwide as well as to various forms of stigma and discrimination in healthcare services. Bosnia and Herzegovina (B&H) is a postconflict developing country located in Southeast Europe and the Western Balkans, where little is known about the experiences of MSM regarding their communities and interactions with healthcare services. The aim of this study was to explore the types of experiences MSM face and to ass...

Do object refixations during scene viewing indicate rehearsal in visual working memory?