Asymmetric Dark Matter and the hadronic spectra of hidden QCD

The idea that dark matter may be a composite state of a hidden nonabelian gauge sector has received great attention in recent years. Frameworks such as asymmetric dark matter motivate the idea that dark matter may have similar mass to the proton, while mirror matter and $G \times G$ grand unified theories provide rationales for additional gauge sectors which may have minimal interactions with standard model particles. In this work we explore the hadronic spectra that these dark QCD models can allow. The effects of the number of light colored particles and the value of the confinement scale on the lightest stable state, the dark matter candidate, are examined in the hyperspherical constituent quark model for baryonic and mesonic states.Comment: 22 pages, 11 figures. Additional discussion, matches published versio

One-electron self-interaction error and its relationship to geometry and higher orbital occupation

Density Functional Theory (DFT) sees prominent use in computational chemistry and physics, however, problems due to the self-interaction error (SIE) pose additional challenges to obtaining qualitatively correct results. An unphysical energy an electron exerts on itself, the SIE impacts most practical DFT calculations. We conduct an in-depth analysis of the one-electron SIE in which we replicate delocalization effects for simple geometries. We present a simple visualization of such effects, which may help in future qualitative analysis of the one-electron SIE. By increasing the number of nuclei in a linear arrangement, the SIE increases dramatically. We also show how molecular shape impacts the SIE. Two and three dimensional shapes show an even greater SIE stemming mainly from the exchange functional with some error compensation from the one-electron error, which we previously defined [Phys. Chem. Chem. Phys. 22, 15805 (2020)]. Most tested geometries are affected by the functional error, while some suffer from the density error. For the latter we establish a potential connection with electrons being unequally delocalized by the DFT methods. We also show how the the SIE increases if electrons occupy higher-lying atomic orbitals; seemingly one-electron SIE free methods in a ground are no longer SIE free in excited states, which is an important insight for some popular, non-empirical DFAs. We conclude that the erratic behavior of the SIE in even the simplest geometries shows that robust density functional approximations are needed. Our test systems can be used as a future benchmark or contribute towards DFT development

Are the psychological benefits of choral singing unique to choirs? A comparison of six activity groups

The present study compared the psychological well-being of choral singers to those who took part in five other activities: solo singers, band / orchestra members, solo musicians, team sport players and solo sport players. These comparison groups were chosen because they each share (or lack) three key features of choral singing: (1) singing; (2) the production of music; and (3) membership of a social group or team. 194 participants completed an online questionnaire to assess their well-being and the extent to which their chosen activity satisfies their psychological needs for autonomy, competence and relatedness. Analysis indicated that participants who sang in a choir reported similar levels of psychological well-being, happiness, anxiety, depression and self-esteem to those who took part in the other five leisure activities. Significant differences were found on measures of autonomy and relatedness, but participants in all six groups also reported experiencing similar levels of competence when engaged in their chosen leisure activity. These findings suggest choral singing may not be uniquely beneficial and any leisure activity that offers opportunities for improvement, mastery of a new skill or a sense of accomplishment might have a positive effect on our psychological well-being

The In Vitro Permeability Of Skin And Buccal Mucosa To Selected Drugs And Tritiated Water

The permeability of whole human skin, human dermis, whole pig skin, and canine buccal mucosa have been determined for four chemically different solutes: tritiated water, amphetamine, estradiol, and ouabain. Several new in vitro techniques for isolation, preservation, and permeability determination of these membranous tissues are described. Water permeabilities of human epidermis and dermis using these techniques agree well with published results. Human and porcine skins are very similar with respect to water permeability, while buccal mucosa is similar to dermis in its permeability characteristics to the four representative test agents. The permeability of hydrated whole skin is determined by the permeability of the epidermis, and the dermis and buccal mucosa behave as if they are water barriers exhibiting a permeability of about 30% of the diffusion through pure water, a difference that can be ascribed to the porosity and/or tortuosity of the tissue matrix

Scarcely visible? Analysing initial teacher education research and the Research Excellence Framework

In the UK, the Research Excellence Framework is a mechanism used for ranking the quality of research in higher education institutions. While there has been analysis of the entire Research Excellence Framework, and of the Education unit of assessment more generally, analysis of how research on initial teacher education featured in the Research Excellence Framework has been minimal. In this article, we report on Phase I of an 18-month project that mapped the extent to which initial teacher education-focused research was included in the 2014 Research Excellence Framework. Employing a novel methodology and a theoretical framework based on policy as text and discourse, we identify a sample of 12 higher education institutions that provided initial teacher education programmes and returned outputs to the 2014 Research Excellence Framework. Analysis of over 1,600 outputs suggest that in the 2014 Research Excellence Framework only 5.5 per cent of these were focused on initial teacher education. We discuss the methodological approach, some headline findings and areas for future research, arguing that these add evidence to the literature of initial teacher education-focused research and, in doing so, can inform policy at the levels of schools, higher education institutions, Research Excellence Framework and the government. We conclude that although the Research Excellence Framework only concerns the UK, similar exercises are becoming increasingly prevalent globally, and therefore the extent to which research on initial teacher education was marginalised in the 2014 Research Excellence Framework is of interest to all concerned with teacher education

Large-scale structure in a new deep IRAS galaxy redshift survey

We present here the first results from two recently completed, fully sampled redshift surveys comprising 3703 IRAS Faint Source Survey (FSS) galaxies. An unbiased counts-in-cells analysis finds a clustering strength in broad agreement with other recent redshift surveys and at odds with the standard cold dark matter model. We combine our data with those from the QDOT and 1.2 Jy surveys, producing a single estimate of the IRAS galaxy clustering strength. We compare the data with the power spectrum derived from a mixed dark matter universe. Direct comparison of the clustering strength seen in the IRAS samples with that seen in the APM-Stromlo survey suggests b_O/b_I=1.20+/-0.05 assuming a linear, scale independent biasing. We also perform a cell by cell comparison of our FSS-z sample with galaxies from the first CfA slice, testing the viability of a linear-biasing scheme linking the two. We are able to rule out models in which the FSS-z galaxies identically trace the CfA galaxies on scales 5-20h^{-1}Mpc. On scales of 5 and 10h^{-1}Mpc no linear-biasing model can be found relating the two samples. We argue that this result is expected since the CfA sample includes more elliptical galaxies which have different clustering properties from spirals. On scales of 20h^{-1}Mpc no linear-biasing model with b_O/b_I < 1.70 is acceptable. When comparing the FSS-z galaxies to the CfA spirals, however, the two populations trace the same structures within our uncertaintie

Increasing girls’ physical activity during an organised youth sport basketball program: a randomised controlled trial protocol

Background: Participation in organised youth sports (OYS) has been recommended as an opportunity to increase young peoples’ moderate-to-vigorous physical activity (MVPA) levels. Participants, however, spend a considerable proportion of time during OYS inactive. The purpose of this study, therefore, was to investigate whether coaches who attended coach education sessions (where education on increasing MVPA and decreasing inactivity during training was delivered) can increase players’ MVPA during training sessions over a 5-day basketball program compared to coaches who did not receive coach education sessions. Methods/design: A convenience sample of 80 female players and 8 coaches were recruited into the UWS School Holiday Basketball Program in Greater Western Sydney, Australia. A two-arm, parallel-group randomised controlled trial was employed to investigate whether coaches who attended 2 coach education sessions (compared with a no-treatment control) can increase their players’ MVPA during training sessions over a 5-day basketball program. Objectively measured physical activity, directly observed lesson context and leader behaviour, player motivation, players’ perceived autonomy support, and coaching information (regarding training session planning, estimations on player physical activity and lesson context during training, perceived ability to modify training sessions, perceived importance of physical activity during training, intention to increase physical activity/reduce inactivity, and likelihood of increasing physical activity/reducing inactivity) were assessed at baseline (day 1) and at follow-up (day 5). Linear mixed models will be used to analyse between arm differences in changes from baseline to follow-up on all outcomes. Discussion: The current trial protocol describes, to our knowledge, the first trial conducted in an OYS context to investigate the efficacy of an intervention, relative to a control, in increasing MVPA. This study’s findings will provide evidence to inform strategies targeting coaches to increase MVPA in OYS, which could have major public health implications, given the high proportion of children and adolescents who participate in OYS globally