Extremal Results for Peg Solitaire on Graphs

In a 2011 paper by Beeler and Hoilman, the game of peg solitaire is generalized to arbitrary boards. These boards are treated as graphs in the combinatorial sense. An open problem from that paper is to determine the minimum number of edges necessary for a graph with a fixed number of vertices to be solvable. This thesis provides new bounds on this number. It also provides necessary and sufficient conditions for two families of graphs to be solvable, along with criticality results, and the maximum number of pegs that can be left in each of the two graph families

Innovativeness and Innovation: Implications for the Renewable Materials Supply Chain

innovativeness, innovation, supply chain management, triple bottom line, corporate social responsibility, Agribusiness, Agricultural Finance, Demand and Price Analysis, Financial Economics, Q10, Q27, Q42, Q47,

Beaconless Optical Communication System Constraints

Deep-space optical communication will enable increased science return and public engagement for robotic and manned missions. The IROC project is studying a beaconless optical communication system for Mars data downlink. A star tracker provides the optical communications pointing information in place of an uplink targeting beacon. The configuration presented in this paper includes a star tracker that is aligned co-boresighted with the optical communication axis. This co-boresight configuration was not discussed in prior work, as it was assumed that large Sun-Probe-Earth keep-out angle requirements for operation of the star tracker would cause significant communication outages. In this paper it is shown that the use of an optimal mechanical mounting angle combined with an advanced star tracker has the capability to yield up to 92% communication availability for an example five-year Mars mission

A Community-based Boxing Program is Associated with Improved Balance in Individuals with Parkinson’s Disease

International Journal of Exercise Science 14(3): 876-884, 2021. In alignment with efforts to mitigate the negative health consequences of Parkinson’s Disease (PD), the purpose of this investigation was to examine if participation in a community-based boxing program (CBP) was associated with improvements in balance and fall risk reduction among individuals with PD. In this retrospective cross-sectional study, de-identified data from 12 individuals with PD participating in a CBP was examined. Participants included those with a Hoehn and Yahr stage between 1 and 3, averaging 2.8 ± 0.8 CBP sessions per week for 6.1 ± 0.8 months between testing. Baseline and re-evaluation testing included the Fullerton Advanced Balance (FAB) Scale and Timed Up and Go (TUG) to quantify balance and fall risk. Sessions were 90-minutes in length involving a warm-up, boxing drills, strength and endurance exercises, and cool down. Sessions included multiple bouts of 30-60 second high-intensity exercise intervals (RPE between 15/20 to 17/20). Paired t-tests were used to determine if differences existed between the FAB and TUG from baseline to re-evaluation, with statistical significance accepted at p \u3c 0.05 and \u3e 0.8 interpreted as a large effect using Cohen’s d. Results indicated a statistically significant increase and large effect in FAB performance, with a mean increase in score above previously reported minimal detectable change (MDC). While participation in CBP was associated with a statistically significant improvement and medium effect in the TUG, this did not demonstrate a population specific MDC. This study found that participation in a CBP was associated with improved balance among clients with PD

The Epidemiology of Severe Injuries Sustained by National Collegiate Athletic Association Student-Athletes, 2009–2010 Through 2014–2015

Few researchers have described the incidence of the most severe injuries sustained by student-athletes at the collegiate level

The Ecology of a Keystone Seed Disperser, the Ant Rhytidoponera violacea

Rhytidoponera violacea (Forel) (Hymenoptera: Formicidae) is a keystone seed disperser in Kwongan heathl and habitats of southwestern Australia. Like many myrmecochorous ants, little is known about the basic biology of this species. In this study various aspects of the biology of R. violacea were examined and the researchers evaluated how these characteristics may influence seed dispersal. R. violacea nesting habits (relatively shallow nests), foraging behavior (scramble competitor and lax food selection criteria), and other life history characteristics complement their role as a mutualist that interacts with the seeds of many plant species

Iridium Corroles

This work reports the synthesis and full characterization of 5,10,15-tris-pentafluorophenylcorrolato-iridium(III) bis-trimethylamine 1 and its octabromo derivative 2. The corrole is planar in both cases (the mean deviation from the plane is as low as 0.0371 Å for 1 and 0.0325 Å for 2), the UV−vis spectra display a split Soret band with a shoulder attributable to an MLCT transition, and cyclic voltammetry reveals that the iridium(II) oxidation state cannot be accessed, while the oxidation to formal iridium(IV) complexes is achieved at much lower potentials than in other coordination environments

Use of injectable hormonal contraception and women’s risk of herpes simplex virus type 2 acquisition: a prospective study of couples in Rakai, Uganda

Background The injectable hormonal contraceptive depo-medroxyprogesterone acetate (DMPA) has been associated with increased risk of HIV acquisition, but fi ndings are inconsistent. Whether DMPA increases the risk of other sexually transmitted viral infections is unknown. We assessed the association between DMPA use and incident herpes simplex virus type 2 (HSV2) infection in women. Methods In this prospective study, we enrolled HIV-negative and HSV2-negative women aged 15–49 years whose HIV-negative male partners were concurrently enrolled in a randomised trial of male circumcision in Rakai, Uganda. We excluded women if either they or their male partners HIV seroconverted. The primary outcome was HSV2 seroconversion, assessed annually. The male circumcision trial was registered with ClinicalTrials.gov, number NCT00425984. Findings Between Aug 11, 2003, and July 6, 2006, we enrolled 682 women in this study. We noted HSV2 seroconversions in 70 (10%) women. Incidence was 13·5 per 100 person-years in women consistently using DMPA (nine incident infections per 66·5 person-years), 4·3 per 100 person-years in pregnant women who were not using hormonal contraception (18 incident infections per 423·5 person-years), and 6·6 per 100 person-years in women who were neither pregnant nor using hormonal contraception (35 incident infections per 529·5 person-years). Women consistently using DMPA had an adjusted hazard ratio for HSV2 seroconversion of 2·26 (95% CI 1·09–4·69; p=0·029) compared with women who were neither pregnant nor using hormonal contraception. Of 132 women with HSV2-seropositive partners, seroconversion was 36·4 per 100 person-years in consistent DMPA users (four incident infections per 11 person-years) and 10·7 per 100 person-years in women who were neither pregnant nor using hormonal contraception (11 incident infections per 103 person-years; adjusted hazard ratio 6·23, 95% CI 1·49–26·3; p=0·012). Interpretation Consistent DMPA use might increase risk of HSV2 seroconversion; however, study power was low. These fi ndings should be assessed in larger populations with more frequent follow-up than in this study, and other contraceptive methods should also be assessed. Access to a wide range of highly eff ective contraceptive methods is needed for women, particularly in sub-Saharan Africa