On biembedding an idempotent latin square with its transpose

Let L be an idempotent Latin square of side n, thought of as a set of ordered triples (i, j, k) where L(I, j) = k. Let I be the set of triples (i, I, i). We consider the problem of biembedding the triples of L\I, with the triples of L'\ I, where L' is the transpose of L, in an orientable surface. We construct such embeddings for all doubly even values of n

The effect of acute fatigue on countermovement jump performance in rugby union players during preseason training

This study aims to capture and explore my personal experiences of trust whilst working as a performance analyst. I began working as a PhD research student and a high performance Paralympic sport performance analyst in April 2014. To critically analyse my role within the team as the sole sports performance analyst, an autoethnographic approach was adopted. Following ethical approval, I maintained a self-reflective diary drawing on my thoughts, opinions and experiences during a fifteen-month period between April 2014 and June 2015. I conducted an inductive thematic content analysis on the recorded reflections whereby the phenomenon of trust emerged as a key theme. To explore the importance of trust, I engage with key theoretical concepts (Hoy and Tschannen-Moran, 1999, Journal of School Leadership, 9, 184-208; Day, 2009, Journal of Educational Administration, 47 (6), 719-730; Sztompka, 2000, Trust: A sociological theory, Cambridge, UK: Cambridge University Press; Hardin, 2002, Trust and Trustworthiness, New York: Russell Sage Foundation) and draw upon the key personality traits and characteristics identified for effective sport science practitioner to excel within their respected discipline (Partington and Orlick, 1987, The Sport Psychologist, 1, 309-317; Lubker et al., 2008, Journal of Sport Behaviour, 31 (2), 147-165). Four essential components for establishing trust between myself, and the athletes and staff were identified: appearance and visibility, confidence, honesty and integrity, and self-care. Stronger athlete-coach-analyst relationships were established once each team member articulated the four components. Athletes and coaches became attuned to the importance of performance analysis and a greater utilisation of the discipline was observed within the team’s practice. Trust therefore must be established by a performance analyst between athletes and coaches in order to advance the provision of performance analysis within a high performance sport system

Plant responses to an edaphic gradient across an active sand dune/desert boundary in the great basin desert.

In arid ecosystems, variation in precipitation causes broad-scale spatial heterogeneity in soil moisture, but differences in soil texture, development, and plant cover can also create substantial local soil moisture heterogeneity. The boundary between inland desert sand dunes and adjacent desert habitats exhibits abrupt changes in soil and vegetation characteristics that may be associated with differences in plant-available water and nutrients. We hypothesized that differences in plant water status between habitats would mirror changes in soil texture and vegetation cover. Because the dunes have higher water availability, we predicted that plants on dunes would have higher plant water potential () and be less water use efficient than plants off dunes. We tested these predictions for three speciesPsoralidium lanceolatum (a C3 perennial N-fixing subshrub), Stipa hymenoides (a C3 perennial bunchgrass), and Salsola iberica (a C4 annual)on actively moving desert dunes and adjacent stabilized dunes at Little Sahara Dunes, Utah. Plants on the dunes maintained higher predawn (pd) water potentials (>-1.5 MPa) throughout the summer season, whereas off-dune plants were water stressed from July on (p

New Hosts for Equine Herpesvirus 9

Equine herpesvirus 9 was detected in a polar bear with progressive encephalitis; the source was traced to 2 members of a potential equid reservoir species, Grevy’s zebras. The virus was also found in an aborted Persian onager. Thus, the natural host range is extended to 6 species in 3 mammalian orders

Counterfactual Thinking and Entrepreneurial Self‐Efficacy: The Moderating Role of Self‐Esteem and Dispositional Affect

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/97291/1/etap472.pd

Risk prioritisation of stormwater pollutant sources

This paper describes the development of a pollutant risk prioritisation methodology for the comparative assessment of stormwater pollutants discharged from differing land use types and activities. Guidelines are presented which evaluate available data with respect to ‘likelihood of occurrence’ and ‘severity of impact’. The use of the developed approach is demonstrated through its application to total suspended solids, biochemical oxygen demand, lead and cadmium. The proposed benchmarking scheme represents a transparent and auditable mechanism to support the synthesis of data from a variety of sources and is sufficiently flexible to incorporate the use of chemical, physical and/or ecological data sets. Practitioners involved in developing and implementing pollutant mitigation programmes are assisted in two key ways. Firstly through enabling the risks to receiving waters from diffuse pollution on a source-by-source and/or pollutant-by-pollutant basis at a catchment scale to be comparatively assessed and prioritised. Secondly, the methodology informs the selection of appropriate diffuse pollution control strategies

Prevalence and Predictors of Substance Use Disorders Among HIV Care Enrollees in the United States

Prior efforts to estimate U.S. prevalence of substance use disorders (SUDs) in HIV care have been undermined by caveats common to single-site trials. The current work reports on a cohort of 10,652 HIV-positive adults linked to care at seven sites, with available patient data including geography, demography, and risk factor indices, and with substance-specific SUDs identified via self-report instruments with validated diagnostic thresholds. Generalized estimating equations also tested patient indices as SUD predictors. Findings were: (1) a 48 % SUD prevalence rate (between-site range of 21–71 %), with 20 % of the sample evidencing polysubstance use disorder; (2) substance-specific SUD rates of 31 % for marijuana, 19 % alcohol, 13 % methamphetamine, 11 % cocaine, and 4 % opiate; and (3) emergence of younger age and male gender as robust SUD predictors. Findings suggest high rates at which SUDs occur among patients at these urban HIV care sites, detail substance-specific SUD rates, and identify at-risk patient subgroups

Identifying HIV care enrollees at-risk for cannabis use disorder

Increased scientific attention given to cannabis in the United States has particular relevance for its domestic HIV care population, given that evidence exists for both cannabis as a therapeutic agent and cannabis use disorder (CUD) as a barrier to antiretroviral medication adherence. It is critical to identify relative risk for CUD among demographic subgroups of HIV patients, as this will inform detection and intervention efforts. A Center For AIDS Research Network of Integrated Clinical Systems cohort (N = 10,652) of HIV-positive adults linked to care at seven United State sites was examined for this purpose. Based on a patient-report instrument with validated diagnostic threshold for CUD, the prevalence of recent cannabis use and corresponding conditional probabilities for CUD were calculated for the aggregate sample and demographic subgroups. Generalized estimating equations then tested models directly examining patient demographic indices as predictors of CUD, while controlling for history and geography. Conditional probability of CUD among cannabis-using patients was 49%, with the highest conditional probabilities among demographic subgroups of young adults and those with non-specified sexual orientation (67–69%) and the lowest conditional probability among females and those 50+ years of age (42% apiece). Similarly, youthful age and male gender emerged as robust multivariate model predictors of CUD. In the context of increasingly lenient policies for use of cannabis as a therapeutic agent for chronic conditions like HIV/AIDS, current study findings offer needed direction in terms of specifying targeted patient groups in HIV care on whom resources for enhanced surveillance and intervention efforts will be most impactful

Influence of Substance Use Disorders on 2-Year HIV Care Retention in the United States

Substance use disorders (SUDs) are thought to predict care discontinuity, though magnitude and substance-specific variance of effects are unclear. This report of analytic work undertaken with a multi-regional American cohort of 9153 care enrollees addresses these gaps. Care retention was computed from 24-month post-linkage clinic visit documentation, with SUD cases identified from patient-report screening instruments. Two generalized estimating equations tested binary and hierarchial SUD predictors of retention, and potential effect modification by patient age-group, sex, and care site. Findings demonstrate: (1) detrimental SUD effect, equivalent to a nine percentage-point decrease in retention, with independent effects of age-group and care site; (2) substance-specific effect of marijuana UD associated with lower retention; and (3) age-modification of each effect on care discontinuity, with SUDs serving as a risk factor among 18–29 year-olds and protective factor among 60+ year-olds. Collective findings document patient attributes as influences that place particular subgroups at-risk to discontinue care