Noise characterization and exposure of indoor sporting events

2012 Spring.Includes bibliographical references.Noise, as a hazard in the work place, has long been recognized as an issue facing workers. The National Institute for Occupational Safety and Health (NIOSH) recognizes that control of noise is a critical issue facing today's employers and employees. Occupational hearing loss was identified as one of the 21 priority areas for research in the next century. A report from the EPA in 1981 estimates that over 9 million Americans are exposed to occupational noise greater than 85 decibels (dB) and more recent estimates from NIOSH indicate excessive noise exposures upwards of 30 million. Occupational and recreational noise exposures were evaluated at a two sporting arenas hosting hockey games at the collegiate and semi-professional level. Between the two facilities studied, a total of 54 personal noise dosimetry samples were taken over the course of seven home hockey games, three at Venue 1 and four at Venue 2. This included 15 worker personal noise samples and nine fan personal noise samples at Venue 1; and 19 worker personal noise samples and 11 fan personal noise samples at Venue 2. Extensive area monitoring was conducted at each venue to further characterize the stadium noise on a location by location basis. These data are useful in characterizing occupational exposure of indoor arena support staff and may also provide a foundation for future research No workers or fans from either venue were exposed to noise in excess of the Occupational Safety and Health Administration (OSHA) permissible exposure limit of an eight-hour time-weighted average (TWA) of 90 A-weighted decibels (dBA) or the eight-hour TWA action limit of 85 dBA. However, six of 15 (40%) workers and three of nine (33%) fans sampled at Venue 1 were exposed to noise in excess of the American Conference of Governmental Industrial Hygienists (ACGIH) recommended threshold limit value (TLV) of 85dBA. In addition, eleven of 19 (57%) workers and ten of 11 (90%) fans sampled at Venue 2 were exposed to noise in excess of the ACGIH noise TLV. A two-way analysis of variance (ANOVA) was conducted on the personal noise dosimetry data from workers and fans to determine if there were significant differences between noise exposures to workers and fans within and between the venues investigated. At a 95% confidence level, it was determined that there were significant noise exposure differences between nearly all groups in evaluating both OSHA and ACGIH criteria. However, no significant noise exposure differences were detected between workers at the different venues

Soluble pre-fibrillar tau and β-amyloid species emerge in early human Alzheimer’s disease and track disease progression and cognitive decline

Acknowledgments We would like to gratefully acknowledge all donors and their families for the tissue provided for this study. Human tissue samples were supplied by the Brains for Dementia Research programme, jointly funded by Alzheimer’s Research UK, the Alzheimer’s Society and the Medical Research Council, and sourced from the MRC London Neurodegenerative Diseases Brain Bank, the Manchester Brain Bank, the South West Dementia Brain Bank (SWDBB), the Newcastle Brain Tissue Resource and the Oxford Brain Bank. The Newcastle Brain Tissue Resource and Oxford Brain Bank are also supported by the National Institute for Health Research (NIHR) Units. The South West Dementia Brain Bank (SWDBB) receives additional support from BRACE (Bristol Research into Alzheimer’s and Care of the Elderly). Alz-50, CP13, MC-1 and PHF-1 antibodies were gifted from Dr. Peter Davies and brain lystates from BACE1−/−mice were obtained from Prof Mike Ashford. The work presented here was funded by Alzheimer’s Research UK (Grant refs: ARUKPPG2014A-21 and ARUK-NSG2015-1 to BP and DK and NIH/NIA grants NIH/NINDS R01 NS082730 and R01 AG044372 to NK)Peer reviewedPublisher PD

Revolutionaries and spies: Spy-good and spy-bad graphs

We study a game on a graph $G$ played by $r$ {\it revolutionaries} and $s$ {\it spies}. Initially, revolutionaries and then spies occupy vertices. In each subsequent round, each revolutionary may move to a neighboring vertex or not move, and then each spy has the same option. The revolutionaries win if $m$ of them meet at some vertex having no spy (at the end of a round); the spies win if they can avoid this forever. Let $\sigma(G,m,r)$ denote the minimum number of spies needed to win. To avoid degenerate cases, assume |V(G)|\ge r-m+1\ge\floor{r/m}\ge 1. The easy bounds are then \floor{r/m}\le \sigma(G,m,r)\le r-m+1. We prove that the lower bound is sharp when $G$ has a rooted spanning tree $T$ such that every edge of $G$ not in $T$ joins two vertices having the same parent in $T$. As a consequence, \sigma(G,m,r)\le\gamma(G)\floor{r/m}, where $\gamma(G)$ is the domination number; this bound is nearly sharp when $\gamma(G)\le m$. For the random graph with constant edge-probability $p$, we obtain constants $c$ and $c'$ (depending on $m$ and $p$) such that $\sigma(G,m,r)$ is near the trivial upper bound when $r<c\ln n$ and at most $c'$ times the trivial lower bound when $r>c'\ln n$. For the hypercube $Q_d$ with $d\ge r$, we have $\sigma(G,m,r)=r-m+1$ when $m=2$, and for $m\ge 3$ at least $r-39m$ spies are needed. For complete $k$-partite graphs with partite sets of size at least $2r$, the leading term in $\sigma(G,m,r)$ is approximately $\frac{k}{k-1}\frac{r}{m}$ when $k\ge m$. For $k=2$, we have \sigma(G,2,r)=\bigl\lceil{\frac{\floor{7r/2}-3}5}\bigr\rceil and \sigma(G,3,r)=\floor{r/2}, and in general $\frac{3r}{2m}-3\le \sigma(G,m,r)\le\frac{(1+1/\sqrt3)r}{m}$.Comment: 34 pages, 2 figures. The most important changes in this revision are improvements of the results on hypercubes and random graphs. The proof of the previous hypercube result has been deleted, but the statement remains because it is stronger for m<52. In the random graph section we added a spy-strategy resul

Making it work: identifying the challenges of collaborative international research

In this article, we explore the challenges – and benefits – of conducting collaborative research on an international scale. The authors – from Australia, Canada, and New Zealand – draw upon their experiences in designing and conducting a three-country study. The growing pressures on scholars to work in collaborative research teams are described, and key findings and reflections are presented. It is claimed that such work is a highly complex and demanding extension to the academic’s role. The authors conclude that, despite the somewhat negative sense that this reflection may convey, the synergies gained and the valuable comparative learning that took place make overcoming these challenges a worthwhile process. The experiences as outlined in this paper suggest that developing understandings of the challenges inherent in undertaking international collaborative research might well be a required component of the professional development opportunities afforded to new scholars

Game saturation of intersecting families

We consider the following combinatorial game: two players, Fast and Slow, claim $k$-element subsets of $[n]=\{1,2,...,n\}$ alternately, one at each turn, such that both players are allowed to pick sets that intersect all previously claimed subsets. The game ends when there does not exist any unclaimed $k$-subset that meets all already claimed sets. The score of the game is the number of sets claimed by the two players, the aim of Fast is to keep the score as low as possible, while the aim of Slow is to postpone the game's end as long as possible. The game saturation number is the score of the game when both players play according to an optimal strategy. To be precise we have to distinguish two cases depending on which player takes the first move. Let $gsat_F(\mathbb{I}_{n,k})$ and $gsat_S(\mathbb{I}_{n,k})$ denote the score of the saturation game when both players play according to an optimal strategy and the game starts with Fast's or Slow's move, respectively. We prove that $\Omega_k(n^{k/3-5}) \le gsat_F(\mathbb{I}_{n,k}),gsat_S(\mathbb{I}_{n,k}) \le O_k(n^{k-\sqrt{k}/2})$ holds

Effects of alternative forages on nitrate leaching under intensive sheep grazing

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Up-regulation of delta-like 4 ligand in human tumor vasculature and the role of basal expression in endothelial cell function.

The Notch signaling pathway and the delta-like 4 ligand (DLL4) play key roles in embryonic vascular development. Many of the pathways involved in embryonic vascular development also play important roles in tumor angiogenesis. In this study, we assessed the expression of DLL4 in primary renal cancer and investigated the biological function of DLL4 in primary endothelial cells. Using real-time quantitative PCR and in situ hybridization, we showed that the expression of DLL4 was up-regulated within the vasculature of clear cell-renal cell carcinoma almost 9-fold more than normal kidney and was correlated with the expression of vascular endothelial growth factor (VEGF). The expression of DLL4 in endothelial cells was up-regulated by VEGF and basic fibroblast growth factor synergistically, and by hypoxia through hypoxia-inducible factor 1alpha. Down-regulation of DLL4 expression with RNA interference led to decreased expression of HEY1 and EphrinB2, and the inhibition of endothelial cell proliferation, migration, and network formation, all of which are important processes in tumor angiogenesis. The inhibition of proliferation occurred via the induction of cell cycle arrest in G0-G1 by increased expression of p21 and decreased phosphorylation of retinoblastoma. We conclude that an optimal window of the DLL4 expression is essential for tumor angiogenesis and that selective modulation of the DLL4 expression within human tumors may represent a potential novel antiangiogenic therapy

Respiratory medicine and thoracic surgery

The document attached has been archived with permission from the editor of the Medical Journal of Australia. An external link to the publisher’s copy is included.John H Alpers, Josephine M Cranston and Alan J Crocket