Towards understanding balancing in exertion games

Playing exertion games with others can be engaging. However, players with different physical skill levels competing against each other can experience reduced engagement because they are either not challenged enough, or challenged too much. Balancing methods can address this; however, there is only limited understanding of balancing in exertion games. In this paper, we identify two distinct dimensional balancing techniques: "internal adjustment" and "external adjustment". We report results from a study where we measured player engagement after applying these adjustments to a digital table tennis game and the traditional table tennis game, finding two disengagement factors: "unexpected physical challenges" and "unacceptable competitive advantage". Based on these factors we derived a set of exertion game design considerations. We conclude that applying digital technology to a physical game can change the required skill level to play the game, and this can affect the impact of these adjustments on player engagement. These results enhances our understanding of balancing in exertion games, supporting the benefits of playing exertion games with others

CD8αα intestinal intraepithelial lymphocytes derived from two thymic precursors seed the intestine in early life

TCRαβ CD4 CD8αα intestinal intraepithelial lymphocytes (CD8αα IEL) descend from thymic precursors. To better define this IEL precursor (IELp) population, we analyzed their maturation, localization, and emigration. Using rigorous lineage exclusion criteria, we defined two precursors among DN TCRβ thymocytes: a nascent PD-1 population and a T-bet population that accumulates with age. Both gave rise to intestinal CD8αα IEL upon adoptive transfer. In adult mice, PD-1 cells contained more self-reactive clones, localized to the cortex, and were dominant in S1PR1-dependent thymic egress. Gut homing α4β7 was already expressed by these IELp at a thymic stage. To understand the kinetics of CD8αα IEL seeding the intestine, we performed "timestamp" experiments: We crossed Cd4 with Rosa26 (stop-floxed tdTomato) mice. In these mice, tamoxifen or its metabolite 4-OHT permanently labels every CD4 expressing cell. As TCRαβ T cells (including CD8αα IEL) go through a CD4 CD8 stage during thymic development, a single dose of tamoxifen or 4-OHT will label thymic IEL precursors permanently, so that they can be tracked when seeding the gut. Our results indicate that these cells enter the intestine during a narrow time window in early life and that this influx is almost completely shut down by the age of 3 weeks. These data provide an important foundation for understanding the biology of this abundant population of barrier surface T cells

Increasing the Quantity of Silver in Zinc-Based Glass Polyalkenoate Cement: is There an Improvement in Antibacterial Efficacy?

Bone cements should have the ability to chemically bond to both bone and surgical metals, exhibit no chemical or thermal necrosis, and have no significant shrinkage or exotherm upon setting. Taking these properties into consideration, glass polyalkenoate cements (GPCs) have potential as bone cements. GPCs are formed by the reaction between an ion-leachable glass and an aqueous solution of polyacrylic acid (PAA) [1] and have proven antibacterial and cariostatic properties [2], which are related to their ability to release beneficial amounts of ions over time [3, 4]. The GPCs can be formulated to release ions that can have a therapeutic benefit in a chosen application such as fluoride release in dental applications [5], which assists in the prevention of secondary caries [6]. Recently, GPCs have been formulated with zinc (Zn) replacing Al; a more biologically acceptable ion [7]. The authors have previously shown that GPCs based on a glass phase containing both Zn and silver (Ag) have the ability to release ions which are antibacterial against both Staphylococcus aureus (Oxford strain) [8] and Pseudomonas aeruginosa (a clinical isolate) [9, 10] in vitro and methicillin-resistant S. aureus (MRSA) both in vitro and in vivo [11]. The authors have also shown that their cements have the ability to inhibit proliferation of a biofilm of P. aeruginosa (PA01) [9]. The objective of the study reported herein is to build on the authors previous publications in order to determine if increases in Ag content of the glass phase of these cements will result in a concomitant increase in antibacterial efficacy of the resultant Ag-Zn GPCs formulated from them. © 2012 IEEE

By hook or by crook? Morphometry, competition and cooperation in rodent sperm

Background Sperm design varies enormously across species and sperm competition is thought to be a major factor influencing this variation. However, the functional significance of many sperm traits is still poorly understood. The sperm of most murid rodents are characterised by an apical hook of the sperm head that varies markedly in extent across species. In the European woodmouse Apodemus sylvaticus (Muridae), the highly reflected apical hook of sperm is used to form sperm groups, or “trains,” which exhibited increased swimming velocity and thrusting force compared to individual sperm. Methodology/Principal Findings Here we use a comparative study of murine rodent sperm and demonstrate that the apical hook and sperm cooperation are likely to be general adaptations to sperm competition in rodents. We found that species with relatively larger testes, and therefore more intense sperm competition, have a longer, more reflected apical sperm hook. In addition, we show that sperm groups also occur in rodents other than the European woodmouse. Conclusions Our results suggest that in rodents sperm cooperation is more widespread than assumed so far and highlight the importance of diploid versus haploid selection in the evolution of sperm design and function

Report of the panel on the land surface: Process of change, section 5

The panel defined three main areas of study that are central to the Solid Earth Science (SES) program: climate interactions with the Earth's surface, tectonism as it affects the Earth's surface and climate, and human activities that modify the Earth's surface. Four foci of research are envisioned: process studies with an emphasis on modern processes in transitional areas; integrated studies with an emphasis on long term continental climate change; climate-tectonic interactions; and studies of human activities that modify the Earth's surface, with an emphasis on soil degradation. The panel concluded that there is a clear requirement for global coverage by high resolution stereoscopic images and a pressing need for global topographic data in support of studies of the land surface

The ferric leaching kinetics of arsenopyrite

Abstract In this investigation batch, ferric leaching experiments were carried out in a 100 m l l jacketed vessel maintained at 258C. The parameters varied during the course of the experimental program included the initial redox potential, the total iron concentration, the solids concentration and the pH of the leaching solution. The initial redox potential used ranged from 625 to 470 mV, the overall iron concentration ranged from 8 to 32 g. l l y1 , the mineral concentration ranged from 5 to 20 g. l l y1 and the initial pH used ranged from 1.10 to 1.45. The redox potential of the leach solution was monitored continuously using a redox probe connected to a computer. The leach rates were calculated from the measured change in the redox potential of the leaching solution. The variation in the ferric leaching rate of the arsenopyrite as a function of the solution redox potential displayed similar trends, irrespective of the conditions employed. The ferric leaching rate of the arsenopyrite decreased with decreasing redox potential of the leaching solution and could be accurately described using a modified Butler-Volmer equation; yr s r e y . High concentrations of ferric iron and protons, and a reduction in the solids Ž concentration were found to impede the leach rate. The 'rest potential' i.e., the redox potential at . which the dissolution of arsenopyrite stops of the arsenopyrite was found to be higher under these conditions. However, no occluding sulphur layer could be detected on the surface of mineral particles, hence the results suggest that the reactivity of the mineral decreases with an increase in the effective concentration of the ferric iron species. Therefore, although the results suggest the Ž . PII: S 0 3 0 4 -3 8 6 X 9 9 0 0 0 0 7 -9 ( ) R. Ruitenberg et al.r Hydrometallurgy 52 1999 37-53 38 likelihood of an electrochemical mechanism being operative, it is necessary to modify the Butler-Volmer-based model to account for the above observations in order to obtain a model capable of predicting the ferric leaching rate of arsenopyrite across a broad range of operating conditions.

Classical Correlation-Length Exponent in Non-Universal Quantum Phase Transition of Diluted Heisenberg Antiferromagnet

Critical behavior of the quantum phase transition of a site-diluted Heisenberg antiferromagnet on a square lattice is investigated by means of the quantum Monte Carlo simulation with the continuous-imaginary-time loop algorithm. Although the staggered spin correlation function decays in a power law with the exponent definitely depending on the spin size $S$, the correlation-length exponent is classical, i.e., $\nu=4/3$. This implies that the length scale characterizing the non-universal quantum phase transition is nothing but the mean size of connected spin clusters.Comment: 4 pages, 3 figure

Choreography, controversy and child sex abuse: Theoretical reflections on a cultural criminological analysis of dance in a pop music video

This article was inspired by the controversy over claims of ‘pedophilia!!!!’ undertones and the ‘triggering’ of memories of childhood sexual abuse in some viewers by the dance performance featured in the music video for Sia’s ‘Elastic Heart’ (2015). The case is presented for acknowledging the hidden and/or overlooked presence of dance in social scientific theory and cultural studies and how these can enhance and advance cultural criminological research. Examples of how these insights have been used within other disciplinary frameworks to analyse and address child sex crime and sexual trauma are provided, and the argument is made that popular cultural texts such as dance in pop music videos should be regarded as significant in analysing and tracing public perceptions and epistemologies of crimes such as child sex abuse

Evaluation of ELISA and haemagglutination inhibition as screening tests in serosurveillance for H5/H7 avian influenza in commercial chicken flocks

Avian influenza virus (AIV) subtypes H5 and H7 can infect poultry causing low pathogenicity (LP) AI, but these LPAIVs may mutate to highly pathogenic AIV in chickens or turkeys causing high mortality, hence H5/H7 subtypes demand statutory intervention. Serological surveillance in the European Union provides evidence of H5/H7 AIV exposure in apparently healthy poultry. To identify the most sensitive screening method as the first step in an algorithm to provide evidence of H5/H7 AIV infection, the standard approach of H5/H7 antibody testing by haemagglutination inhibition (HI) was compared with an ELISA, which detects antibodies to all subtypes. Sera (n = 1055) from 74 commercial chicken flocks were tested by both methods. A Bayesian approach served to estimate diagnostic test sensitivities and specificities, without assuming any 'gold standard'. Sensitivity and specificity of the ELISA was 97% and 99.8%, and for H5/H7 HI 43% and 99.8%, respectively, although H5/H7 HI sensitivity varied considerably between infected flocks. ELISA therefore provides superior sensitivity for the screening of chicken flocks as part of an algorithm, which subsequently utilises H5/H7 HI to identify infection by these two subtypes. With the calculated sensitivity and specificity, testing nine sera per flock is sufficient to detect a flock seroprevalence of 30% with 95% probability