421 research outputs found
New evidence for Green's conjecture on syzygies of canonical curves
We prove that two weakened forms of Green's conjectures for canonical curves
are equivalent when the genus is odd.Comment: Tex-type: LaTe
Initiality for Typed Syntax and Semantics
We give an algebraic characterization of the syntax and semantics of a class
of simply-typed languages, such as the language PCF: we characterize
simply-typed binding syntax equipped with reduction rules via a universal
property, namely as the initial object of some category. For this purpose, we
employ techniques developed in two previous works: in [2], we model syntactic
translations between languages over different sets of types as initial
morphisms in a category of models. In [1], we characterize untyped syntax with
reduction rules as initial object in a category of models. In the present work,
we show that those techniques are modular enough to be combined: we thus
characterize simply-typed syntax with reduction rules as initial object in a
category. The universal property yields an operator which allows to specify
translations - that are semantically faithful by construction - between
languages over possibly different sets of types.
We specify a language by a 2-signature, that is, a signature on two levels:
the syntactic level specifies the types and terms of the language, and
associates a type to each term. The semantic level specifies, through
inequations, reduction rules on the terms of the language. To any given
2-signature we associate a category of models. We prove that this category has
an initial object, which integrates the types and terms freely generated by the
2-signature, and the reduction relation on those terms generated by the given
inequations. We call this object the (programming) language generated by the
2-signature.
[1] Ahrens, B.: Modules over relative monads for syntax and semantics (2011),
arXiv:1107.5252, to be published in Math. Struct. in Comp. Science
[2] Ahrens, B.: Extended Initiality for Typed Abstract Syntax. Logical
Methods in Computer Science 8(2), 1-35 (2012)Comment: presented at WoLLIC 2012, 15 page
Pseudoconvex domains spread over complex homogeneous manifolds
Using the concept of inner integral curves defined by Hirschowitz we
generalize a recent result by Kim, Levenberg and Yamaguchi concerning the
obstruction of a pseudoconvex domain spread over a complex homogeneous manifold
to be Stein. This is then applied to study the holomorphic reduction of
pseudoconvex complex homogeneous manifolds X=G/H. Under the assumption that G
is solvable or reductive we prove that X is the total space of a G-equivariant
holomorphic fiber bundle over a Stein manifold such that all holomorphic
functions on the fiber are constant.Comment: 21 page
Plasma PGE-2 levels and altered cytokine profiles in adherent peripheral blood mononuclear cells in non-small cell lung cancer (NSCLC)
INTRODUCTION: PGE-2 is constitutively produced by many non-small cell lung cancers (NSCLC) and its immunosuppressive effects have been linked to altered immune responses in lung cancer. We asked whether elevated levels of plasma PGE-2 correlated with monocyte IL10 production in the NSCLC environment. Looking for correlation in NSCLC patient blood we assayed plasma from NSCLC patients for PGE2 and IL10; we further evaluated production of IL10 by adherent mononuclear cells from a subset of these patients looking for an altered cytokine profile. RESULTS: Our initial in vitro experiments show that monocyte IL10 induction correlates with tumor cell PGE-2 production, confirming similar reports in the literature. Data show plasma PGE-2 levels in 38 NSCLC patients are elevated compared to normal controls. Plasma IL10 levels were not significantly elevated; however, adherent monocytes derived from NSCLC patient blood did produce significantly more IL10 in 24 hr primary culture than those from normal controls (p < 0.01). The association of elevated plasma PGE-2 and monocyte derived IL-10 was not significant. CONCLUSIONS: Elevated plasma PGE-2 and monocyte IL10 production are associated with NSCLC. The biological significance to elevated PGE-2 levels in NSCLC are unclear. Further investigation of each as a nonspecific marker for NSCLC tumor is warranted
Variable binding, symmetric monoidal closed theories, and bigraphs
This paper investigates the use of symmetric monoidal closed (SMC) structure
for representing syntax with variable binding, in particular for languages with
linear aspects. In our setting, one first specifies an SMC theory T, which may
express binding operations, in a way reminiscent from higher-order abstract
syntax. This theory generates an SMC category S(T) whose morphisms are, in a
sense, terms in the desired syntax. We apply our approach to Jensen and
Milner's (abstract binding) bigraphs, which are linear w.r.t. processes. This
leads to an alternative category of bigraphs, which we compare to the original.Comment: An introduction to two more technical previous preprints. Accepted at
Concur '0
Autoantibody Profiling for Lung Cancer Screening Longitudinal Retrospective Analysis of CT Screening Cohorts
Recommendations for lung cancer screening present a tangible opportunity to integrate predictive blood-based assays with radiographic imaging. This study compares performance of autoantibody markers from prior discovery in sample cohorts from two CT screening trials. One-hundred eighty non-cancer and 6 prevalence and 44 incidence cancer cases detected in the Mayo Lung Screening Trial were tested using a panel of six autoantibody markers to define a normal range and assign cutoff values for class prediction. A cutoff for minimal specificity and best achievable sensitivity were applied to 256 samples drawn annually for three years from 95 participants in the Kentucky Lung Screening Trial. Data revealed a discrepancy in quantile distribution between the two apparently comparable sample sets, which skewed the assay’s dynamic range towards specificity. This cutoff offered 43% specificity (102/237) in the control group and accurately classified 11/19 lung cancer samples (58%), which included 4/5 cancers at time of radiographic detection (80%), and 50% of occult cancers up to five years prior to diagnosis. An apparent ceiling in assay sensitivity is likely to limit the utility of this assay in a conventional screening paradigm. Pre-analytical bias introduced by sample age, handling or storage remains a practical concern during development, validation and implementation of autoantibody assays. This report does not draw conclusions about other logical applications for autoantibody profiling in lung cancer diagnosis and management, nor its potential when combined with other biomarkers that might improve overall predictive accuracy
Regina Lectures on Fat Points
These notes are a record of lectures given in the Workshop on Connections
Between Algebra and Geometry at the University of Regina, May 29--June 1, 2012.
The lectures were meant as an introduction to current research problems related
to fat points for an audience that was not expected to have much background in
commutative algebra or algebraic geometry (although sections 8 and 9 of these
notes demand somewhat more background than earlier sections).Comment: 32 pages, 3 figure
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