Homogeneous links, Seifert surfaces, digraphs and the reduced Alexander polynomial

We give a geometric proof of the following result of Juhasz. \emph{Let $a_g$ be the leading coefficient of the Alexander polynomial of an alternating knot $K$. If $|a_g|<4$ then $K$ has a unique minimal genus Seifert surface.} In doing so, we are able to generalise the result, replacing `minimal genus' with `incompressible' and `alternating' with `homogeneous'. We also examine the implications of our proof for alternating links in general.Comment: 37 pages, 28 figures; v2 Main results generalised from alternating links to homogeneous links. Title change

Prrx1b restricts fibrosis and promotes Nrg1-dependent cardiomyocyte proliferation during zebrafish heart regeneration

Therapeutic cell differentiatio

Heart regeneration in the Mexican cavefish.

Although Astyanax mexicanus surface fish regenerate their hearts after injury, their Pachón cave-dwelling counterparts cannot and, instead, form a permanent fibrotic scar, similar to the human heart. Myocardial proliferation peaks at similar levels in both surface fish and Pachón 1 week after injury. However, in Pachón, this peak coincides with a strong scarring and immune response, and ultimately, cavefish cardiomyocytes fail to replace the scar. We identified lrrc10 to be upregulated in surface fish compared with Pachón after injury. Similar to cavefish, knockout of lrrc10 in zebrafish impairs heart regeneration without affecting wound cardiomyocyte proliferation. Furthermore, using quantitative trait locus (QTL) analysis, we have linked the degree of heart regeneration to three loci in the genome, identifying candidate genes fundamental to the difference between scarring and regeneration. Our study provides evidence that successful heart regeneration entails a delicate interplay between cardiomyocyte proliferation and scarring

Dynamic Bioluminescence Imaging: Development of a Physiological Pharmacokinetic Model of Tumor Metabolism

poster abstractBioluminescence (BLI) is a technology which has been studied extensively across multiple genera for more than 90 years. Over this period, BLI has emerged as a powerful noninvasive tool to study tumor localization, growth, and response to therapy due to the relatively recent technological advancements in instrumentation and molecular biology. This technology takes advantage of molecular transfection of the luciferase (LUC) gene from the North American firefly, Photinus pyralis, into human cancer cells, which are then implanted (ectopic or orthotopic) in mice. Oxidation of the exogenously administered substrate D-luciferin by the LUC gene product results in emission of green-yellow photons which are then evaluated in the context of tumor growth and development. Despite the more than 30 years of characterization, there exists a fundamental gap in our knowledge of the underlying PK/PD processes which are at the heart of nearly all BLI interpretation, and has lead to a dogmatic adherence in the literature to numerical methods which are at best simple corollaries of tumor metabolic rate. In an attempt to fill this void, this paper will present a new PK/PD model which takes advantage of the temporal nature of both substrate transport and light evolution. In addition, we will compare these results to traditional non-model based analyses and show how they differ. Lastly we will present OATS (One at A Time) Parameter Sensitivity and Monte Carlo Noise Analysis to characterize the numerical stability and sensitivity of this new model

Single Spin Asymmetry ANA_N in Polarized Proton-Proton Elastic Scattering at s=200\sqrt{s}=200 GeV

We report a high precision measurement of the transverse single spin asymmetry $A_N$ at the center of mass energy $\sqrt{s}=200$ GeV in elastic proton-proton scattering by the STAR experiment at RHIC. The $A_N$ was measured in the four-momentum transfer squared $t$ range $0.003 \leqslant |t| \leqslant 0.035$ \GeVcSq, the region of a significant interference between the electromagnetic and hadronic scattering amplitudes. The measured values of $A_N$ and its $t$-dependence are consistent with a vanishing hadronic spin-flip amplitude, thus providing strong constraints on the ratio of the single spin-flip to the non-flip amplitudes. Since the hadronic amplitude is dominated by the Pomeron amplitude at this $\sqrt{s}$, we conclude that this measurement addresses the question about the presence of a hadronic spin flip due to the Pomeron exchange in polarized proton-proton elastic scattering.Comment: 12 pages, 6 figure

Schuldig landschap. Over de toeristische aantrekkingskracht van Baantjer, Wallander en Inspector Morse

De opnamelokaties van tv-detectives genieten een toenemende populariteit onder toeristen. In dit artikel wordt, op basis van een tekstuele analyse van ‘Baantjer’, ‘Inspector Morse’ en ‘Wallander’, onderzocht welke inhoudelijke kenmerken van deze tv-detectives mogelijk als ‘trigger’ fungeren. Uit de analyse blijkt dat plaats en beweging een centrale rol vervullen binnen de narratieve structuur van dit genre. Door zelf de lokaties te bezoeken, kunnen toeristen het spoor nalopen van hun geliefde detective om aldaar, vanuit een veilige positie, tijdelijk op te gaan in het schemergebied tussen fictie en werkelijkheid

Stratification of asthma phenotypes by airway proteomic signatures

© 2019 Background: Stratification by eosinophil and neutrophil counts increases our understanding of asthma and helps target therapy, but there is room for improvement in our accuracy in prediction of treatment responses and a need for better understanding of the underlying mechanisms. Objective: We sought to identify molecular subphenotypes of asthma defined by proteomic signatures for improved stratification. Methods: Unbiased label-free quantitative mass spectrometry and topological data analysis were used to analyze the proteomes of sputum supernatants from 246 participants (206 asthmatic patients) as a novel means of asthma stratification. Microarray analysis of sputum cells provided transcriptomics data additionally to inform on underlying mechanisms. Results: Analysis of the sputum proteome resulted in 10 clusters (ie, proteotypes) based on similarity in proteomic features, representing discrete molecular subphenotypes of asthma. Overlaying granulocyte counts onto the 10 clusters as metadata further defined 3 of these as highly eosinophilic, 3 as highly neutrophilic, and 2 as highly atopic with relatively low granulocytic inflammation. For each of these 3 phenotypes, logistic regression analysis identified candidate protein biomarkers, and matched transcriptomic data pointed to differentially activated underlying mechanisms. Conclusion: This study provides further stratification of asthma currently classified based on quantification of granulocytic inflammation and provided additional insight into their underlying mechanisms, which could become targets for novel therapies

J/ψ polarization in p+p collisions at s=200 GeV in STAR

AbstractWe report on a polarization measurement of inclusive J/ψ mesons in the di-electron decay channel at mid-rapidity at 2<pT<6 GeV/c in p+p collisions at s=200 GeV. Data were taken with the STAR detector at RHIC. The J/ψ polarization measurement should help to distinguish between different models of the J/ψ production mechanism since they predict different pT dependences of the J/ψ polarization. In this analysis, J/ψ polarization is studied in the helicity frame. The polarization parameter λθ measured at RHIC becomes smaller towards high pT, indicating more longitudinal J/ψ polarization as pT increases. The result is compared with predictions of presently available models

Measurements of differential production cross sections for a Z boson in association with jets in pp collisions at root s=8 TeV

Peer reviewe