Lossy Image Compression with Compressive Autoencoders

We propose a new approach to the problem of optimizing autoencoders for lossy image compression. New media formats, changing hardware technology, as well as diverse requirements and content types create a need for compression algo- rithms which are more flexible than existing codecs. Autoencoders have the po- tential to address this need, but are difficult to optimize directly due to the inherent non-differentiabilty of the compression loss. We here show that minimal changes to the loss are sufficient to train deep autoencoders competitive with JPEG 2000 and outperforming recently proposed approaches based on RNNs. Our network is furthermore computationally efficient thanks to a sub-pixel architecture, which makes it suitable for high-resolution images. This is in contrast to previous work on autoencoders for compression using coarser approximations, shallower archi- tectures, computationally expensive methods, or focusing on small image

A Systematic Mapping Review of Health Promotion and Well-being Concepts in Physical Therapy

BACKGROUND AND PURPOSE: The American Physical Therapy Association adopted the International Classification of Functioning, Disability, and Health (ICF) in 2008. ICF provided universal terminology for health professions, defined health in bio-psychosocial terms, and introduced neutral language and contextual influences on health (World Health Organization, 2001). The primary purpose of this study was to create a descriptive map of the physical therapy (PT) literature specific to the areas of health promotion (HP), prevention, and well-being and the use of ICF terminology. The secondary intent was to explore the status of research and topics of interest physical therapy pertaining to these areas. METHODS: A systematic mapping review aims to evaluate the knowledge of or evidence for specific areas (Evidence for Policy and Practice Information Centre, 2010). It allows researchers to conduct an in-depth review and construct a descriptive map of the literature, gain an understanding of the state of affairs pertaining to scholarship of a particular concept or topic, and identify gaps and directions for future study (Grant & Booth, 2009). Comprehensive database searches were conducted using combinations of the search terms “physical therapy,” “health promotion,” “wellness,” and “well-being.” Ultimately, 132 articles met study criteria and were analyzed. A coding sheet was created using ICF terminology and tested for inter-rater reliability, and each article was reviewed. Articles were classified as primary prevention for healthy populations or secondary/tertiary prevention for those with a diagnosis. The coded articles were charted for further descriptive analysis and identification of themes. RESULTS: Four major subcategories were identified in the articles: wellness, well-being, quality of life (QOL), or HP. The distribution of articles for well-being, wellness, and HP were fairly even for primary prevention, and only 10% of the articles involved QOL. However, the majority of articles related to secondary/tertiary prevention coded for well-being (48.4%) or QOL (45.3%). Both primary prevention and secondary/tertiary prevention articles most commonly coded for exercise (75% and 87.5, respectively) and mood (55% and 81%, respectively). Other recurring primary prevention article codes were balance (32%), musculoskeletal (29%), and neuromuscular (26%). Secondary/tertiary prevention articles had common codes of neuromuscular (53%), pain (50%), and mobility (47%). CONCLUSIONS: The composition of PT literature on primary prevention in healthy individuals and secondary/tertiary prevention in individuals with diagnosis is markedly different. It appears that researchers associate HP and wellness with healthy populations, and QOL and well-being with populations with a diagnosis. The inconsistent and interchangeable use of language was a challenge for systematic analysis

Photo-Realistic Single Image Super-Resolution Using a Generative Adversarial Network

Despite the breakthroughs in accuracy and speed of single image super-resolution using faster and deeper convolutional neural networks, one central problem remains largely unsolved: how do we recover the finer texture details when we super-resolve at large upscaling factors? The behavior of optimization-based super-resolution methods is principally driven by the choice of the objective function. Recent work has largely focused on minimizing the mean squared reconstruction error. The resulting estimates have high peak signal-to-noise ratios, but they are often lacking high-frequency details and are perceptually unsatisfying in the sense that they fail to match the fidelity expected at the higher resolution. In this paper, we present SRGAN, a generative adversarial network (GAN) for image super-resolution (SR). To our knowledge, it is the first framework capable of inferring photo-realistic natural images for 4x upscaling factors. To achieve this, we propose a perceptual loss function which consists of an adversarial loss and a content loss. The adversarial loss pushes our solution to the natural image manifold using a discriminator network that is trained to differentiate between the super-resolved images and original photo-realistic images. In addition, we use a content loss motivated by perceptual similarity instead of similarity in pixel space. Our deep residual network is able to recover photo-realistic textures from heavily downsampled images on public benchmarks. An extensive mean-opinion-score (MOS) test shows hugely significant gains in perceptual quality using SRGAN. The MOS scores obtained with SRGAN are closer to those of the original high-resolution images than to those obtained with any state-of-the-art method

Male and LGBT survivors of sexual violence in conflict situations: a realist review of health interventions in low-and middle-income countries

Conflict-related sexual violence (CRSV) against women and girls has been the subject of increasing research and scholarship. Less is known about the health of men, boys and lesbian, gay, bisexual, transgender (LGBT) and other gender non-binary persons who survive CRSV. This paper is the first systematic realist review on medical, mental health and psychosocial support (MHPSS) interventions that focusses on male and LGBT survivors of CRSV. The review explores the gender differences in context, mechanisms and outcomes that underpin interventions addressing the health and psychosocial wellbeing of male and LGBT survivors. The aim is to contribute to the design and delivery of gender-sensitive and, when needed, gender-specific approaches for interventions that respond to specific needs of different groups of all survivors. We conducted a systematic search of academic and grey literature to identify medical and MHPSS interventions that included men, boys and LGBT survivors. We identified interventions specifically targeting women and girls that we used as comparators. We then purposively sampled studies from the fields of gender and health, and sexual abuse against men and LGBT people for theory building and testing. We identified 26 evaluations of interventions for survivors of CRSV. Nine studies included male survivors, twelve studies focussed exclusively on female survivors and one study targeted children and adolescents. No intervention evaluation focussed on LGBT survivors of CRSV. The interventions that included male survivors did not describe specific components for this population. Results of intervention evaluations that included male survivors were not disaggregated by gender, and some studies did not report the gender composition. Although some mental health and psychosocial consequences of sexual violence against men and boys may be similar among male and female survivors, the way each process trauma, display symptoms, seek help, adhere to treatment and improve their mental health differ by gender. Initiatives targeting male and LGBT survivors of CRSV need to be designed to actively address specific gender differences in access, adherence and response to MHPSS interventions. Models of care that are gender-sensitive and integrated to local resources are promising avenues to promote the health of male and LGBT survivors of CRSV

Applying the causal roadmap to longitudinal national Danish registry data: a case study of second-line diabetes medication and dementia

The causal roadmap is a formal framework for causal and statistical inference that supports clear specification of the causal question, interpretable and transparent statement of required causal assumptions, robust inference, and optimal precision. The roadmap is thus particularly well-suited to evaluating longitudinal causal effects using large scale registries; however, application of the roadmap to registry data also introduces particular challenges. In this paper we provide a detailed case study of the longitudinal causal roadmap applied to the Danish National Registry to evaluate the comparative effectiveness of second-line diabetes drugs on dementia risk. Specifically, we evaluate the difference in counterfactual five-year cumulative risk of dementia if a target population of adults with type 2 diabetes had initiated and remained on GLP-1 receptor agonists (a second-line diabetes drug) compared to a range of active comparator protocols. Time-dependent confounding is accounted for through use of the iterated conditional expectation representation of the longitudinal g-formula as a statistical estimand. Statistical estimation uses longitudinal targeted maximum likelihood, incorporating machine learning. We provide practical guidance on the implementation of the roadmap using registry data, and highlight how rare exposures and outcomes over long-term follow up can raise challenges for flexible and robust estimators, even in the context of the large sample sizes provided by the registry. We demonstrate how simulations can be used to help address these challenges by supporting careful estimator pre-specification. We find a protective effect of GLP-1RAs compared to some but not all other second-line treatments

Does Stellar Feedback Create HI Holes? An HST/VLA Study of Holmberg II

We use deep HST/ACS F555W and F814W photometry of resolved stars in the M81 Group dwarf irregular galaxy Ho II to study the hypothesis that the holes identified in the neutral ISM (HI) are created by stellar feedback. From the deep photometry, we construct color-magnitude diagrams (CMDs) and measure the star formation histories (SFHs) for stars contained in HI holes from two independent holes catalogs, as well as select control fields, i.e., similar sized regions that span a range of HI column densities. Converting the recent SFHs into stellar feedback energies, we find that enough energy has been generated to have created all holes. However, the required energy is not always produced over a time scale that is less than the estimated kinematic age of the hole. The combination of the CMDs, recent SFHs, and locations of young stars shows that the stellar populations inside HI holes are not coherent, single-aged, stellar clusters, as previously suggested, but rather multi-age populations distributed across each hole. From a comparison of the modeled and observed integrated magnitudes, and the locations and energetics of stars inside of HI holes, we propose a potential new model: a viable mechanism for creating the observed HI holes in Ho II is stellar feedback from multiple generations of SF spread out over tens or hundreds of Myr, and thus, the concept of an age for an HI hole is intrinsically ambiguous. We further find that \halpha and 24 micron emission, tracers of the most recent star formation, do not correlate well with the positions of the HI holes. However, UV emission, which traces star formation over roughly the last 100 Myr, shows a much better correlation with the locations of the HI holes.Comment: Accepted for Publication in The Astrophysical Journal; 28 Pages, 31 Figures, a version of this paper with full resolution figures is available at http://homepages.spa.umn.edu/~dweisz/ho_ii_weisz.pd

Bacteria in the amniotic fluid without inflammation: Early colonization vs. contamination

Objectives: Intra-amniotic infection, defined by the presence of microorganisms in the amniotic cavity, is often accompanied by intra-amniotic inflammation. Occasionally, laboratories report the growth of bacteria or the presence of microbial nucleic acids in amniotic fluid in the absence of intra-amniotic inflammation. This study was conducted to determine the clinical significance of the presence of bacteria in amniotic fluid samples in the absence of intra-amniotic inflammation. Methods: A retrospective cross-sectional study included 360 patients with preterm labor and intact membranes who underwent transabdominal amniocentesis for evaluation of the microbial state of the amniotic cavity as well as intra-amniotic inflammation. Cultivation techniques were used to isolate microorganisms, and broad-range polymerase chain reaction coupled with electrospray ionization mass spectrometry (PCR/ESI-MS) was utilized to detect the nucleic acids of bacteria, viruses, and fungi. Results: Patients whose amniotic fluid samples evinced microorganisms but did not indicate inflammation had a similar perinatal outcome to those without microorganisms or inflammation [amniocentesis-to-delivery interval (p=0.31), spontaneous preterm birth before 34 weeks (p=0.83), acute placental inflammatory lesions (p=1), and composite neonatal morbidity (p=0.8)]. Conclusions: The isolation of microorganisms from a sample of amniotic fluid in the absence of intra-amniotic inflammation is indicative of a benign condition, which most likely represents contamination of the specimen during the collection procedure or laboratory processing rather than early colonization or infection

On the Origin of the Supergiant HI Shell and Putative Companion in NGC 6822

We present new Hubble Space Telescope Advanced Camera for Surveys imaging of six positions spanning 5.8 kpc of the HI major axis of the Local Group dIrr NGC 6822, including both the putative companion galaxy and the large HI hole. The resulting deep color magnitude diagrams show that NGC 6822 has formed >50% of its stars in the last ~5 Gyr. The star formation histories of all six positions are similar over the most recent 500 Myr, including low-level star formation throughout this interval and a weak increase in star formation rate during the most recent 50 Myr. Stellar feedback can create the giant HI hole, assuming that the lifetime of the structure is longer than 500 Myr; such long-lived structures have now been observed in multiple systems and may be the norm in galaxies with solid-body rotation. The old stellar populations (red giants and red clump stars) of the putative companion are consistent with those of the extended halo of NGC 6822; this argues against the interpretation of this structure as a bona fide interacting companion galaxy and against its being linked to the formation of the HI hole via an interaction. Since there is no evidence in the stellar population of a companion galaxy, the most likely explanation of the extended HI structure in NGC 6822 is a warped disk inclined to the line of sight.Comment: The Astrophysical Journal, in press. Full-resolution version available on request from the first autho