Layered Fabrication of Branched Networks Using Lindenmayer Systems

A current challenge impeding the growth of bone tissue engineering is the lack of functional scaffolds of geometric sizes greater than 10mm due to the inability of cells to survive deep within the scaffold. It is hypothesized that these scaffolds must have an inbuilt nutrient distribution network to sustain the uniform growth of cells. In this paper, we seek to enhance the design and layered fabrication of scaffold internal architecture through the development of Lindenmayer systems, a graphical language based theory to create nutrient delivery networks. The scaffolds are fabricated using the Texas Instruments DLP™ system through UV‐photopolymerization to produce polyethylene glycol hydrogels with internal branch structures. The paper will discuss the Lindenmayer system, process planning algorithms, layered fabrication of samples, challenges and future tasks.Mechanical Engineerin

Using self-categorization theory to uncover the framing of the 2015 Rugby World Cup: a cross-cultural comparison of three nations’ newspapers

Research into the framing of sporting events has been extensively studied to uncover newspaper bias in the coverage of global sporting events. Through discourse, the media attempt to capture, build, and maintain audiences for the duration of sporting events through the use of multiple narratives and/or storylines. Little research has looked at the ways in which the same event is reported across different nations, and media representations of the Rugby World Cup have rarely featured in discussions of the framing of sport events. The present study highlights the different ways in which rugby union is portrayed across the three leading Southern Hemisphere nations in the sport. It also shows the prominence of nationalistic discourse across those nations and importance of self-categorizations in newspaper narratives.</jats:p

Physicians' perceptions of an electronic health record-based clinical trial alert approach to subject recruitment: A survey

<p>Abstract</p> <p>Background</p> <p>Physician participation in clinical research recruitment efforts is critical to many studies' success, but it is often limited. Use of an Electronic Health Record (EHR)-based, point-of-care Clinical Trial Alert (CTA) approach has led to significant increases in physician-generated recruitment and holds promise for wider benefit. However, little is known about physicians' decision-making regarding recruitment in EHR-equipped settings or the use of such EHR-based approaches. We sought to assess physicians' perceptions about recruitment in general and using the CTA approach in particular.</p> <p>Methods</p> <p>We developed and delivered a Web-based survey consisting of 15 multiple-choice and free-text questions. Participants included the 114 physician subjects (10 endocrinologists and 104 general internists) who were exposed to CTAs during our preceding 4-month intervention study. Response data were descriptively analyzed, and key findings were compared between groups using appropriate statistical tests.</p> <p>Results</p> <p>Sixty-nine physicians (61%) responded during the 10-week survey period. Respondents and non-respondents did not differ significantly. Twenty-seven percent of respondents felt very comfortable recruiting patients to trials in general, and 77% appreciated being reminded about a trial via a CTA. Only 11% percent felt the CTA was difficult to use, and 27% felt it was more than somewhat intrusive. Among those who ignored all CTAs, 37% cited a lack of time, 28% knowledge of the patient's ineligibility, and 13% limited knowledge about the trial as their most common reason. Thirty-eight percent wanted more information about the trial presented in the CTA, and 73% were interested in seeing CTAs for future trials. Comments and suggestions were submitted by 33% of respondents and included suggestions for improvement of the CTA approach.</p> <p>Conclusion</p> <p>Most physicians were comfortable recruiting patients for clinical trials at the point-of-care, found the EHR-based CTA approach useful and would like to see it used in the future. These findings provide insight into the perceived utility of this EHR-based approach to subject recruitment, suggest ways it might be improved, and add to the limited body of knowledge regarding physicians' attitudes toward clinical trial recruitment in EHR-equipped settings.</p

Qualitative Freshwater Mussel Survey of the South Fork Spring River, Missouri and Arkansas

A qualitative freshwater mussel survey was performed in the South Fork Spring River, Arkansas between May 13 and June 20, 2006 to assess community composition, density, and the presence of endangered mussel species (Family Unionidae). Twenty-one species from 460 individuals of mussels were collected using qualitative methods. Of those 21 species, 11 were ranked as S1, S2, or S3 using rankings established by the Arkansas Natural Heritage Commission Heritage Program. Three species, Amblema plicata (Say 1817), Lampsilis reeveiana (Call 1887), and Ptychobranchus occidentalis (Conrad 1836), comprised 48% of all mussels collected with 12%, 15%, and 21%, respectively. Mussel abundance within beds ranged between 2 to 33 individuals/site with an overall mean of 13 individuals/site. Selecting mussel beds for long-term monitoring in streams is necessary to assess population status and recruitment and to document success of future stream restoration projects

Cryogenic mechanical loss of a single-crystalline GaP coating layer for precision measurement applications

The first direct observations of gravitational waves have been made by the Advanced LIGO detectors. However, the quest to improve the sensitivities of these detectors remains, and epitaxially grown single-crystal coatings show considerable promise as alternatives to the ion-beam sputtered amorphous mirror coatings typically used in these detectors and other such precision optical measurements. The mechanical loss of a 1 μm thick single-crystalline gallium phosphide (GaP) coating, incorporating a buffer layer region necessary for the growth of high quality epitaxial coatings, has been investigated over a broad range of frequencies and with fine temperature resolution. It is shown that at 20 K the mechanical loss of GaP is a factor of 40 less than an undoped tantala film heat-treated to 600 °C and is comparable to the loss of a multilayer GaP/AlGaP coating. This is shown to translate into possible reductions in coating thermal noise of a factor of 2 at 120 K and 5 at 20 K over the current best IBS coatings (alternating stacks of silica and titania-doped tantala). There is also evidence of a thermally activated dissipation process between 50 and 70 K

Pkd1 transgenic mice: Adult model of polycystic kidney disease with extrarenal and renal phenotypes

While high levels of Pkd1 expression are detected in tissues of patients with autosomal dominant polycystic kidney disease (ADPKD), it is unclear whether enhanced expression could be a pathogenetic mechanism for this systemic disorder. Three transgenic mouse lines were generated from a Pkd1-BAC modified by introducing a silent tag via homologous recombination to target a sustained wild type genomic Pkd1 expression within the native tissue and temporal regulation. These mice specifically overexpressed the Pkd1 transgene in extrarenal and renal tissues from approximately 2- to 15-fold over Pkd1 endogenous levels in a copy-dependent manner. All transgenic mice reproducibly developed tubular and glomerular cysts leading to renal insufficiency. Interestingly, Pkd1(TAG) mice also exhibited renal fibrosis and calcium deposits in papilla reminiscent of nephrolithiasis as frequently observed in ADPKD. Similar to human ADPKD, these mice consistently displayed hepatic fibrosis and approximately 15% intrahepatic cysts of the bile ducts affecting females preferentially. Moreover, a significant proportion of mice developed cardiac anomalies with severe left ventricular hypertrophy, marked aortic arch distention and/or valvular stenosis and calcification that had profound functional impact. Of significance, Pkd1(TAG) mice displayed occasional cerebral lesions with evidence of ruptured and unruptured cerebral aneurysms. This Pkd1(TAG) mouse model demonstrates that overexpression of wildtype Pkd1 can trigger the typical adult renal and extrarenal phenotypes resembling human ADPKD.This work was supported by the Canadian Institutes of Health Research (CIHR) [MOP-81325 to MT] and a CIHR Frederick Banting and Charles Best studentship to AK and a Fonds de la Recherche en Santé du Québec (FRSQ) studentship to MC

Polysaccharide utilization loci and nutritional specialization in a dominant group of butyrate-producing human colonic Firmicutes

Acknowledgements The Rowett Institute of Nutrition and Health (University of Aberdeen) receives financial support from the Scottish Government Rural and Environmental Sciences and Analytical Services (RESAS). POS is a PhD student supported by the Scottish Government (RESAS) and the Science Foundation Ireland, through a centre award to the APC Microbiome Institute, Cork, Ireland. Data Summary The high-quality draft genomes generated in this work were deposited at the European Nucleotide Archive under the following accession numbers: 1. Eubacterium rectale T1-815; CVRQ01000001–CVRQ0100 0090: http://www.ebi.ac.uk/ena/data/view/PRJEB9320 2. Roseburia faecis M72/1; CVRR01000001–CVRR010001 01: http://www.ebi.ac.uk/ena/data/view/PRJEB9321 3. Roseburia inulinivorans L1-83; CVRS01000001–CVRS0 100 0151: http://www.ebi.ac.uk/ena/data/view/PRJEB9322Peer reviewedPublisher PD

Volatility distribution in the S&P500 Stock Index

We study the volatility of the S&P500 stock index from 1984 to 1996 and find that the volatility distribution can be very well described by a log-normal function. Further, using detrended fluctuation analysis we show that the volatility is power-law correlated with Hurst exponent $\alpha\cong0.9$.Comment: 6 pages, 5 figure

Chandra Discovery of a 300 kpc X-ray Jet in the GPS Quasar PKS1127-145

We have discovered an X-ray jet with Chandra imaging of the z=1.187 radio-loud quasar PKS1127-145. In this paper we present the Chandra X-ray data, follow-up VLA observations, and optical imaging using the HST WFPC2. The X-ray jet contains 273+/-5 net counts in 27ksec and extends ~30 arcsec, from the quasar core, corresponding to a minimum projected linear size of ~330/h_50 kpc. The evaluation of the X-ray emission processes is complicated by the observed offsets between X-ray and radio brightness peaks. We discuss the problems posed by these observations to jet models. In addition, PKS1127-145 is a Giga-Hertz Peaked Spectrum radio source, a member of the class of radio sources suspected to be young or ``frustrated'' versions of FRI radio galaxies. However the discovery of an X-ray and radio jet extending well outside the host galaxy of PKS1127-145 suggests that activity in this and other GPS sources may be long-lived and complex.Comment: 22 pages, 11 ps figures, 1 figure in a JPG file, 3 tables. AASTEX. Accepted by The Astrophysical Journa