Beyond Flicker, Beyond Blur: View-coherent Metameric Light Fields for Foveated Display

Ventral metamers, pairs of images which may differ substantially in the periphery, but are perceptually identical, offer exciting new possibilities in foveated rendering and image compression, as well as offering insights into the human visual system. However, existing lit-erature has mainly focused on creating metamers of static images. In this work, we develop a method for creating sequences of metameric frames, specifically light fields, with enforced consistency along the temporal, or angular, dimension. This greatly expands the potential applications for these metamers, and expanding metamers along the third dimension offers further new potential for compression

Perceptually guided Computer-Generated Holography

Computer-Generated Holography (CGH) promises to deliver genuine, high-quality visuals at any depth. We argue that combining CGH and perceptually guided graphics can soon lead to practical holographic display systems that deliver perceptually realistic images. We propose a new CGH method called metameric varifocal holograms. Our CGH method generates images only at a user’s focus plane while displayed images are statistically correct and indistinguishable from actual targets across peripheral vision (metamers). Thus, a user observing our holograms is set to perceive a high quality visual at their gaze location. At the same time, the integrity of the image follows a statistically correct trend in the remaining peripheral parts. We demonstrate our differentiable CGH optimization pipeline on modern GPUs, and we support our findings with a display prototype. Our method will pave the way towards realistic visuals free from classical CGH problems, such as speckle noise or poor visual quality

Beyond blur: real-time ventral metamers for foveated rendering

To peripheral vision, a pair of physically different images can look the same. Such pairs are metamers relative to each other, just as physically-different spectra of light are perceived as the same color. We propose a real-time method to compute such ventral metamers for foveated rendering where, in particular for near-eye displays, the largest part of the framebuffer maps to the periphery. This improves in quality over state-of-the-art foveation methods which blur the periphery. Work in Vision Science has established how peripheral stimuli are ventral metamers if their statistics are similar. Existing methods, however, require a costly optimization process to find such metamers. To this end, we propose a novel type of statistics particularly well-suited for practical real-time rendering: smooth moments of steerable filter responses. These can be extracted from images in time constant in the number of pixels and in parallel over all pixels using a GPU. Further, we show that they can be compressed effectively and transmitted at low bandwidth. Finally, computing realizations of those statistics can again be performed in constant time and in parallel. This enables a new level of quality for foveated applications such as such as remote rendering, level-of-detail and Monte-Carlo denoising. In a user study, we finally show how human task performance increases and foveation artifacts are less suspicious, when using our method compared to common blurring

Measuring Nepotism through Shared Last Names: The Case of Italian Academia

Nepotistic practices are detrimental for academia. Here I show how disciplines with a high likelihood of nepotism can be detected using standard statistical techniques based on shared last names among professors. As an example, I analyze the set of all 61,340 Italian academics. I find that nepotism is prominent in Italy, with particular disciplinary sectors being detected as especially problematic. Out of 28 disciplines, 9 – accounting for more than half of Italian professors – display a significant paucity of last names. Moreover, in most disciplines a clear north-south trend emerges, with likelihood of nepotism increasing with latitude. Even accounting for the geographic clustering of last names, I find that for many disciplines the probability of name-sharing is boosted when professors work in the same institution or sub-discipline. Using these techniques policy makers can target cuts and funding in order to promote fair practices

Preparation, structural characterisation and antibacterial properties of Ga-doped sol-gel phosphate-based glass

A sol-gel preparation of Ga-doped phosphate-based glass with potential application in antimicrobial devices has been developed. Samples of composition (CaO)(0.30)(Na2O)(0.20-x) (Ga2O3) (x) (P2O5)(0.50) where x = 0 and 0.03 were prepared, and the structure and properties of the gallium-doped sample compared with those of the sample containing no gallium. Analysis of the P-31 MAS NMR data demonstrated that addition of gallium to the sol-gel reaction increases the connectivity of the phosphate network at the expense of hydroxyl groups. This premise is supported by the results of the elemental analysis, which showed that the gallium-free sample contains significantly more hydrogen and by FTIR spectroscopy, which revealed a higher concentration of -OH groups in that sample. Ga K-edge extended X-ray absorption fine structure and X-ray absorption near-edge structure data revealed that the gallium ions are coordinated by six oxygen atoms. In agreement with the X-ray absorption data, the high-energy XRD results also suggest that the Ga3+ ions are octahedrally coordinated with respect to oxygen. Antimicrobial studies demonstrated that the sample containing Ga3+ ions had significant activity against Staphylococcus aureus compared to the control

Sources of decline, turnaround strategy and HR strategies and practices: The case of Iberia Airlines

This study investigates the coevolution of the sources of decline, the turnaround strategy and the human resource strategy (HRS) at Iberia Airlines, together with the influence of employee responses to these strategies. The analysis of several moments of organisational decline at Iberia, comparing measures adopted in pre- and post-financial crisis periods, shows that, in a sector experiencing a fiercely competitive transformation that negatively affects established companies, the use of downsizing in an organisation with internal deficiencies may create further problems within the company, while an HRS based on flexibility-oriented practices and a fostering approach to strategic negotiations will improve the requisite recovery strategy.Management and Marketing Department (University of Pablo de Olavide

ENIGMA and global neuroscience: A decade of large-scale studies of the brain in health and disease across more than 40 countries.

This review summarizes the last decade of work by the ENIGMA (Enhancing NeuroImaging Genetics through Meta Analysis) Consortium, a global alliance of over 1400 scientists across 43 countries, studying the human brain in health and disease. Building on large-scale genetic studies that discovered the first robustly replicated genetic loci associated with brain metrics, ENIGMA has diversified into over 50 working groups (WGs), pooling worldwide data and expertise to answer fundamental questions in neuroscience, psychiatry, neurology, and genetics. Most ENIGMA WGs focus on specific psychiatric and neurological conditions, other WGs study normal variation due to sex and gender differences, or development and aging; still other WGs develop methodological pipelines and tools to facilitate harmonized analyses of "big data" (i.e., genetic and epigenetic data, multimodal MRI, and electroencephalography data). These international efforts have yielded the largest neuroimaging studies to date in schizophrenia, bipolar disorder, major depressive disorder, post-traumatic stress disorder, substance use disorders, obsessive-compulsive disorder, attention-deficit/hyperactivity disorder, autism spectrum disorders, epilepsy, and 22q11.2 deletion syndrome. More recent ENIGMA WGs have formed to study anxiety disorders, suicidal thoughts and behavior, sleep and insomnia, eating disorders, irritability, brain injury, antisocial personality and conduct disorder, and dissociative identity disorder. Here, we summarize the first decade of ENIGMA's activities and ongoing projects, and describe the successes and challenges encountered along the way. We highlight the advantages of collaborative large-scale coordinated data analyses for testing reproducibility and robustness of findings, offering the opportunity to identify brain systems involved in clinical syndromes across diverse samples and associated genetic, environmental, demographic, cognitive, and psychosocial factors

Priority setting in developing countries health care institutions: the case of a Ugandan hospital

BACKGROUND: Because the demand for health services outstrips the available resources, priority setting is one of the most difficult issues faced by health policy makers, particularly those in developing countries. However, there is lack of literature that describes and evaluates priority setting in these contexts. The objective of this paper is to describe priority setting in a teaching hospital in Uganda and evaluate the description against an ethical framework for fair priority setting processes – Accountability for Reasonableness. METHODS: A case study in a 1,500 bed national referral hospital receiving 1,320 out patients per day and an average budget of US$ 13.5 million per year. We reviewed documents and carried out 70 in-depth interviews (14 health planners, 40 doctors, and 16 nurses working at the hospital). Interviews were recorded and transcribed. Data analysis employed the modified thematic approach to describe priority setting, and the description was evaluated using the four conditions of Accountability for Reasonableness: relevance, publicity, revisions and enforcement. RESULTS: Senior managers, guided by the hospital strategic plan make the hospital budget allocation decisions. Frontline practitioners expressed lack of knowledge of the process. Relevance: Priority is given according to a cluster of factors including need, emergencies and patient volume. However, surgical departments and departments whose leaders "make a lot of noise" are also prioritized. Publicity: Decisions, but not reasons, are publicized through general meetings and circulars, but this information does not always reach the frontline practitioners. Publicity to the general public was through ad hoc radio programs and to patients who directly ask. Revisions: There were no formal mechanisms for challenging the reasoning. Enforcement: There were no mechanisms to ensure adherence to the four conditions of a fair process. CONCLUSION: Priority setting decisions at this hospital do not satisfy the conditions of fairness. To improve, the hospital should: (i) engage frontline practitioners, (ii) publicize the reasons for decisions both within the hospital and to the general public, and (iii) develop formal mechanisms for challenging the reasoning. In addition, capacity strengthening is required for senior managers who must accept responsibility for ensuring that the above three conditions are met

Non-Hematopoietic Cells in Lymph Nodes Drive Memory CD8 T Cell Inflation during Murine Cytomegalovirus Infection

During human and murine cytomegalovirus (MCMV) infection an exceptionally large virus-specific CD8 T cell pool is maintained in the periphery lifelong. This anomalous response is only seen for specific subsets of MCMV-specific CD8 T cells which are referred to as 'inflationary T cells'. How memory CD8 T cell inflation is induced and maintained is unclear, though their activated phenotype strongly suggests an involvement of persistent antigen encounter during MCMV latency. To dissect the cellular and molecular requirements for memory CD8 T cell inflation, we have generated a transgenic mouse expressing an MHC class I-restricted T cell receptor specific for an immunodominant inflationary epitope of MCMV. Through a series of adoptive transfer experiments we found that memory inflation was completely dependent on antigen presentation by non-hematopoietic cells, which are also the predominant site of MCMV latency. In particular, non-hematopoietic cells selectively induced robust proliferation of inflationary CD8 T cells in lymph nodes, where a majority of the inflationary CD8 T cells exhibit a central-memory phenotype, but not in peripheral tissues, where terminally differentiated inflationary T cells accumulate. These results indicate that continuous restimulation of central memory CD8 T cells in the lymph nodes by infected non-hematopoietic cells ensures the maintenance of a functional effector CD8 T pool in the periphery, providing protection against viral reactivation events

Turning around an ailing district hospital: a realist evaluation of strategic changes at Ho Municipal Hospital (Ghana)

<p>Abstract</p> <p>Background</p> <p>There is a growing consensus that linear approaches to improving the performance of health workers and health care organisations may only obtain short-term results. An alternative approach premised on the principle of human resource management described as a form of 'High commitment management', builds upon a bundles of balanced practices. This has been shown to contribute to better organisational performance. This paper illustrates an intervention and outcome of high commitment management (HiCom) at an urban hospital in Ghana. Few studies have shown how HiCom management might contribute to better performance of health services and in particular of hospitals in low and middle-income settings.</p> <p>Methods</p> <p>A realist case study design was used to analyse how specific management practices might contribute to improving the performance of an urban district hospital in Ho, Volta Region, in Ghana. Mixed methods were used to collect data, including document review, in-depth interviews, group discussions, observations and a review of routine health information.</p> <p>Results</p> <p>At Ho Municipal Hospital, the management team dealt with the crisis engulfing the ailing urban district hospital by building an alliance between hospital staff to generate a sense of ownership with a focus around participative problem analysis. The creation of an alliance led to improving staff morale and attitude, and contributed also to improvements in the infrastructure and equipment. This in turn had a positive impact on the revenue generating capacity of the hospital. The quick turn around in the state of this hospital showed that change was indeed possible, a factor that greatly motivated the staff.</p> <p>In a second step, the management team initiated the development of a strategic plan for the hospital to maintain the dynamics of change. This was undertaken through participative methods and sustained earlier staff involvement, empowerment and feelings of reciprocity. We found that these factors acted as the core mechanisms underlying the changes taking place at Ho Municipal Hospital.</p> <p>Conclusions</p> <p>This study shows how a hospital management team in Ghana succeeded in resuscitating an ailing hospital. Their high commitment management approach led to the active involvement and empowerment of staff. It also showed how a realist evaluation approach such as this, could be used in the research of the management of health care organisations to explain how management interventions may or may not work.</p