70 research outputs found
An Abstraction of Whitney's Broken Circuit Theorem
We establish a broad generalization of Whitney's broken circuit theorem on
the chromatic polynomial of a graph to sums of type
where is a finite set and is a mapping from the power set of into
an abelian group. We give applications to the domination polynomial and the
subgraph component polynomial of a graph, the chromatic polynomial of a
hypergraph, the characteristic polynomial and Crapo's beta invariant of a
matroid, and the principle of inclusion-exclusion. Thus, we discover several
known and new results in a concise and unified way. As further applications of
our main result, we derive a new generalization of the maximums-minimums
identity and of a theorem due to Blass and Sagan on the M\"obius function of a
finite lattice, which generalizes Rota's crosscut theorem. For the classical
M\"obius function, both Euler's totient function and its Dirichlet inverse, and
the reciprocal of the Riemann zeta function we obtain new expansions involving
the greatest common divisor resp. least common multiple. We finally establish
an even broader generalization of Whitney's broken circuit theorem in the
context of convex geometries (antimatroids).Comment: 18 page
Hepatitis C virus pharmacogenomics in Latin American populations: implications in the era of direct-acting antivirals
In recent years, great progress has been made in the field of new therapeutic options for hepatitis C virus (HCV) infection. The new direct-acting antiviral agents (DAAs) represent a great hope for millions of chronically infected individuals because their use may lead to excellent cure rates with fewer side effects. In Latin America, the high prevalence of HCV genotype 1 infection and the significant association of Native American ancestry with risk predictive single-nucleotide polymorphisms (SNPs) in IFNL4 and ITPA genes highlight the need to implement new treatment regimens in these populations. However, the universal accessibility to DAAs is still not a reality in the region as their high cost is one of the major, although not the only, limiting factors for their broad implementation. Therefore, under these circumstances, could the assessment of host genetic markers be a useful tool to prioritize DAA treatment until global access to these new drugs can be achieved? This review will summarize the scientific evidences and the potential implications of HCV pharmacogenomics in this rapidly evolving era of anti-HCV drug development.Fil: Trinks, Julieta. Hospital Italiano. Instituto de Ciencias Básicas y Medicina Experimental; Argentina. Consejo Nacional de Investigaciones CientÃficas y Técnicas; ArgentinaFil: Caputo, Mariela. Universidad de Buenos Aires. Facultad de Farmacia y BioquÃmica. Servicio de Huellas Digitales Genéticas; Argentina. Consejo Nacional de Investigaciones CientÃficas y Técnicas; ArgentinaFil: Hulaniuk, MarÃa L.. Hospital Italiano. Instituto de Ciencias Básicas y Medicina Experimental; ArgentinaFil: Corach, Daniel. Universidad de Buenos Aires. Facultad de Farmacia y BioquÃmica. Servicio de Huellas Digitales Genéticas; Argentina. Consejo Nacional de Investigaciones CientÃficas y Técnicas; ArgentinaFil: Flichman, Diego Martin. Universidad de Buenos Aires. Facultad de Farmacia y BioquÃmica; Argentina. Consejo Nacional de Investigaciones CientÃficas y Técnicas; Argentin
Multidisciplinary investigation of the pit circuit at Durrington Walls, UK
ISBN: 9782753585874.– Comprehensive geophysical assessment of huge pits; ERT, GPR, mag and EM. – Novel approach to testing and interpreting pits via coring. – Largest pit circuit confirmed in both the Stonehenge landscape and the UK.Publisher PDFPeer reviewe
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