Quality of Experience Comparison of Stereoscopic 3D Videos in Different Projection Devices: Flat Screen, Panoramic Screen and Virtual Reality Headset

The use of Stereoscopic 3D (S3D) videos has been popular in commercial markets with ongoing developments in the field of visual entertainment in recent years. A wide variety of projection methods of 3D video content is currently available, such as projection to a panoramic screen and projection of omnidirectional video content from head mounted displays using Virtual Reality (VR) technology. This article investigates the Quality of Experience (QoE) and associated Visually Induced Motion Sickness (VIMS) caused by the viewing of S3D videos. The investigations used three different projection screens: a 3D flat screen, a 3D panoramic screen in a hemispherical shaped room and a VR headset. Several assessment methods including a Simulator Sickness Questionnaire (SSQ), ElectroEncephaloGraphy (EEG), and measurement tools for eye blink rate detection were applied to measure the QoE experienced by viewers. The SSQ scores were also compared with the behavioral data such as attention and meditation levels and enjoyment ratings acquired from different video content and projection screens. The results indicate that the projection screen is a key factor affecting the level of visual fatigue, VIMS and QoE assessments, which are discussed in-depth in the article

The blind men and the AML elephant:can we feel the progress?

The pharmacological therapy of non-promyelocytic acute myeloid leukemia (AML) has remained unchanged for over 40 years with an anthracycline–cytarabine combination forming the backbone of induction treatments. Nevertheless, the survival of younger patients has increased due to improved management of the toxicity of therapies including stem cell transplantation. Older patients and those with infirmity that precludes treatment-intensification have, however, not benefited from improvements in supportive care and continue to experience poor outcomes. An increased understanding of the genomic heterogeneity of AML raises the possibility of treatment-stratification to improve prognosis. Thus, efforts to identify agents with non-conventional anti-leukemic effects have paralleled those aiming to optimize leukemia cell-kill with conventional chemotherapy, resulting in a number of randomized controlled trials (RCT). In the last 18 months, RCTs investigating the effects of vosaroxin, azacitidine and gemtuzumab ozogamycin and daunorubicin dose have been reported with some studies indicating a statistically significant survival benefit with the investigational agent compared with standard therapy and potentially, a new era in AML therapeutics. Given the increasing costs of cancer care, a review of these studies, with particular attention to the magnitude of clinical benefit with the newer agents would be useful, especially for physicians treating patients in single-payer health systems

Load and speed effects on the cervical flexion relaxation phenomenon

<p>Abstract</p> <p>Background</p> <p>The flexion relaxation phenomenon (FRP) represents a well-studied neuromuscular response that occurs in the lumbar and cervical spine. However, the cervical spine FRP has not been investigated extensively, and the speed of movement and loading effects remains to be characterized. The objectives of the present study were to evaluate the influence of load and speed on cervical FRP electromyographic (EMG) and kinematic parameters and to assess the measurement of cervical FRP kinematic and EMG parameter repeatability.</p> <p>Methods</p> <p>Eighteen healthy adults (6 women and 12 men), aged 20 to 39 years, participated in this study. They undertook 2 sessions in which they had to perform a standardized cervical flexion/extension movement in 3 phases: complete cervical flexion; the static period in complete cervical flexion; and extension with return to the initial position. Two different rhythm conditions and 3 different loading conditions were applied to assess load and speed effects. Kinematic and EMG data were collected, and dependent variables included angles corresponding to the onset and cessation of myoelectric silence as well as the root mean square (RMS) values of EMG signals. Repeatability was examined in the first session and between the 2 sessions.</p> <p>Results</p> <p>Statistical analyses revealed a significant load effect (P < 0.001). An augmented load led to increased FRP onset and cessation angles. No load × speed interaction effect was detected in the kinematics data. A significant load effect (P < 0.001) was observed on RMS values in all phases of movement, while a significant speed effect (P < 0.001) could be seen only during the extension phase. Load × speed interaction effect was noted in the extension phase, where higher loads and faster rhythm generated significantly greater muscle activation. Intra-session and inter-session repeatability was good for the EMG and kinematic parameters.</p> <p>Conclusions</p> <p>The load increase evoked augmented FRP onset and cessation angles as well as heightened muscle activation. Such increments may reflect the need to enhance spinal stability under loading conditions. The kinematic and EMG parameters showed promising repeatability. Further studies are needed to assess kinematic and EMG differences between healthy subjects and patients with neck pain.</p

Theorems on existence and global dynamics for the Einstein equations

This article is a guide to theorems on existence and global dynamics of solutions of the Einstein equations. It draws attention to open questions in the field. The local-in-time Cauchy problem, which is relatively well understood, is surveyed. Global results for solutions with various types of symmetry are discussed. A selection of results from Newtonian theory and special relativity that offer useful comparisons is presented. Treatments of global results in the case of small data and results on constructing spacetimes with prescribed singularity structure or late-time asymptotics are given. A conjectural picture of the asymptotic behaviour of general cosmological solutions of the Einstein equations is built up. Some miscellaneous topics connected with the main theme are collected in a separate section.Comment: Submitted to Living Reviews in Relativity, major update of Living Rev. Rel. 5 (2002)

The controversy of patellar resurfacing in total knee arthroplasty: Ibisne in medio tutissimus?

Early arthroplasty designs were associated with a high level of anterior knee pain as they failed to cater for the patello-femoral joint. Patellar resurfacing was heralded as the saviour safeguarding patient satisfaction and success but opinion on its necessity has since deeply divided the scientific community and has become synonymous to topics of religion or politics. Opponents of resurfacing contend that the native patella provides better patellar tracking, improved clinical function, and avoids implant-related complications, whilst proponents argue that patients have less pain, are overall more satisfied, and avert the need for secondary resurfacing. The question remains whether complications associated with patellar resurfacing including those arising from future component revision outweigh the somewhat increased incidence of anterior knee pain recorded in unresurfaced patients. The current scientific literature, which is often affected by methodological limitations and observer bias, remains confusing as it provides evidence in support of both sides of the argument, whilst blinded satisfaction studies comparing resurfaced and non-resurfaced knees generally reveal equivalent results. Even national arthroplasty register data show wide variations in the proportion of patellar resurfacing between countries that cannot be explained by cultural differences alone. Advocates who always resurface or never resurface indiscriminately expose the patella to a random choice. Selective resurfacing offers a compromise by providing a decision algorithm based on a propensity for improved clinical success, whilst avoiding potential complications associated with unnecessary resurfacing. Evidence regarding the validity of selection criteria, however, is missing, and the decision when to resurface is often based on intuitive reasoning. Our lack of understanding why, irrespective of pre-operative symptoms and patellar resurfacing, some patients may suffer pain following TKA and others may not have so far stifled our efforts to make the strategy of selective resurfacing succeed. We should hence devote our efforts in defining predictive criteria and indicators that will enable us to reliably identify those individuals who might benefit from a resurfacing procedure. Level of evidence V

Caspase-3 Mediates the Pathogenic Effect of \u3cem\u3e Yersinia pestis \u3c/em\u3e YopM in Liver of C57BL/6 Mice and Contributes to YopM\u27s Function in Spleen

The virulence protein YopM of the plague bacterium Yersinia pestis has different dominant effects in liver and spleen. Previous studies focused on spleen, where YopM inhibits accumulation of inflammatory dendritic cells. In the present study we focused on liver, where PMN function may be directly undermined by YopM without changes in inflammatory cell numbers in the initial days of infection, and foci of inflammation are easily identified. Mice were infected with parent and ΔyopM-1 Y. pestis KIM5, and effects of YopM were assessed by immunohistochemistry and determinations of bacterial viable numbers in organs. The bacteria were found associated with myeloid cells in foci of inflammation and in liver sinusoids. A new in-vivo phenotype of YopM was revealed: death of inflammatory cells, evidenced by TUNEL staining beginning at d 1 of infection. Based on distributions of Ly6G+, F4/80+, and iNOS+ cells within foci, the cells that were killed could have included both PMNs and macrophages. By 2 d post-infection, YopM had no effect on distribution of these cells, but by 3 d cellular decomposition had outstripped acute inflammation in foci due to parent Y. pestis, while foci due to the Δ-1yopM strain still contained many inflammatory cells. The destruction depended on the presence of both PMNs in the mice and YopM in the bacteria. In mice that lacked the apoptosis mediator caspase-3 the infection dynamics were novel: the parent Y. pestis was limited in growth comparably to the ΔyopM-1 strain in liver, and in spleen a partial growth limitation for parent Y. pestis was seen. This result identified caspase-3 as a co-factor or effector in YopM\u27s action and supports the hypothesis that in liver YopM\u27s main pathogenic effect is mediated by caspase-3 to cause apoptosis of PMNs

Vocal Accuracy and Neural Plasticity Following Micromelody-Discrimination Training

Recent behavioral studies report correlational evidence to suggest that non-musicians with good pitch discrimination sing more accurately than those with poorer auditory skills. However, other studies have reported a dissociation between perceptual and vocal production skills. In order to elucidate the relationship between auditory discrimination skills and vocal accuracy, we administered an auditory-discrimination training paradigm to a group of non-musicians to determine whether training-enhanced auditory discrimination would specifically result in improved vocal accuracy.We utilized micromelodies (i.e., melodies with seven different interval scales, each smaller than a semitone) as the main stimuli for auditory discrimination training and testing, and we used single-note and melodic singing tasks to assess vocal accuracy in two groups of non-musicians (experimental and control). To determine if any training-induced improvements in vocal accuracy would be accompanied by related modulations in cortical activity during singing, the experimental group of non-musicians also performed the singing tasks while undergoing functional magnetic resonance imaging (fMRI). Following training, the experimental group exhibited significant enhancements in micromelody discrimination compared to controls. However, we did not observe a correlated improvement in vocal accuracy during single-note or melodic singing, nor did we detect any training-induced changes in activity within brain regions associated with singing.Given the observations from our auditory training regimen, we therefore conclude that perceptual discrimination training alone is not sufficient to improve vocal accuracy in non-musicians, supporting the suggested dissociation between auditory perception and vocal production

Understanding the Role of the Josephin Domain in the PolyUb Binding and Cleavage Properties of Ataxin-3

Ataxin-3, the disease protein in the neurodegenerative disorder Spinocerebellar Ataxia Type 3 or Machado Joseph disease, is a cysteine protease implicated in the ubiquitin proteasome pathway. It contains multiple ubiquitin binding sites through which it anchors polyubiquitin chains of different linkages that are then cleaved by the N-terminal catalytic (Josephin) domain. The properties of the ubiquitin interacting motifs (UIMs) in the C-terminus of ataxin-3 are well established. Very little is known, however, about how two recently identified ubiquitin-binding sites in the Josephin domain contribute to ubiquitin chain binding and cleavage. In the current study, we sought to define the specific contribution of the Josephin domain to the catalytic properties of ataxin-3 and assess how the topology and affinity of these binding sites modulate ataxin-3 activity. Using NMR we modeled the structure of diUb/Josephin complexes and showed that linkage preferences are imposed by the topology of the two binding sites. Enzymatic studies further helped us to determine a precise hierarchy between the sites. We establish that the structure of Josephin dictates specificity for K48-linked chains. Site 1, which is close to the active site, is indispensable for cleavage. Our studies open the way to understand better the cellular function of ataxin-3 and its link to pathology