262 research outputs found
Deformation of dual Leibniz algebra morphisms
An algebraic deformation theory of morphisms of dual Leibniz algebras is
obtained.Comment: 10 pages. To appear in Communications in Algebr
Discrete and Continuous-time Soft-Thresholding with Dynamic Inputs
There exist many well-established techniques to recover sparse signals from
compressed measurements with known performance guarantees in the static case.
However, only a few methods have been proposed to tackle the recovery of
time-varying signals, and even fewer benefit from a theoretical analysis. In
this paper, we study the capacity of the Iterative Soft-Thresholding Algorithm
(ISTA) and its continuous-time analogue the Locally Competitive Algorithm (LCA)
to perform this tracking in real time. ISTA is a well-known digital solver for
static sparse recovery, whose iteration is a first-order discretization of the
LCA differential equation. Our analysis shows that the outputs of both
algorithms can track a time-varying signal while compressed measurements are
streaming, even when no convergence criterion is imposed at each time step. The
L2-distance between the target signal and the outputs of both discrete- and
continuous-time solvers is shown to decay to a bound that is essentially
optimal. Our analyses is supported by simulations on both synthetic and real
data.Comment: 18 pages, 7 figures, journa
Manin products, Koszul duality, Loday algebras and Deligne conjecture
In this article we give a conceptual definition of Manin products in any
category endowed with two coherent monoidal products. This construction can be
applied to associative algebras, non-symmetric operads, operads, colored
operads, and properads presented by generators and relations. These two
products, called black and white, are dual to each other under Koszul duality
functor. We study their properties and compute several examples of black and
white products for operads. These products allow us to define natural
operations on the chain complex defining cohomology theories. With these
operations, we are able to prove that Deligne's conjecture holds for a general
class of operads and is not specific to the case of associative algebras.
Finally, we prove generalized versions of a few conjectures raised by M. Aguiar
and J.-L. Loday related to the Koszul property of operads defined by black
products. These operads provide infinitely many examples for this generalized
Deligne's conjecture.Comment: Final version, a few references adde
Cost-Effectiveness of Web-Based Patient-Reported Outcome Surveillance in Patients With Lung Cancer
INTRODUCTION: A multicenter randomized clinical trial in France found an overall survival benefit of web-based patient-reported outcome (PRO)-based surveillance after initial treatment for lung cancer compared with conventional surveillance. The aim of this study was to assess the cost-effectiveness of this PRO-based surveillance in lung cancer patients.
METHODS: This medico-economic analysis used data from the clinical trial, augmented by abstracted chart data and costs of consultations, imaging, transportations, information technology, and treatments. Costs were calculated based on actual reimbursement rates in France, and health utilities were estimated based on scientific literature review. Willingness-to-pay thresholds of €30,000 per quality-adjusted life year (QALY) and €90,000 per QALY were used to define a very cost-effective and cost-effective strategy, respectively. Average annual costs of experimental and control surveillance approaches were calculated. The incremental cost-effectiveness ratio was expressed as cost per life-year gained and QALY gained, from the health insurance payer perspective. One-way and multivariate probabilistic sensitivity analyses were performed.
RESULTS: Average annual cost of surveillance follow-up was €362 lower per patient in the PRO arm (€941/year/patient) compared to control (€1,304/year/patient). The PRO approach presented an incremental cost-effectiveness ratio of €12,127 per life-year gained and €20,912 per QALY gained. The probabilities that the experimental strategy is very cost-effective and cost-effective were 97% and 100%, respectively.
CONCLUSIONS: Surveillance of lung cancer patients using web-based PRO reduced the follow-up costs. Compared to conventional monitoring, this surveillance modality represents a cost-effective strategy and should be considered in cancer care delivery
Rapid Publication Prostaglandin E2 and Collagenase Production by Fibroblasts and Synovial Cells Is Regulated by Urine-derived Human Interleukin 1 and Inhibitor(s)
Abstract Interleukin 1 (IL-1) possesses multiple biological activities that may be blocked selectively by different inhibitors. Some known inhibitors block the lymphocyte activating factor (LAF/IL-1) but not the mononuclear cell factor (MCF/IL-1) measured by its capacity to stimulate prostaglandin E2 (PGE2) and colingenase production. The presence of IL-1 in vivo may be difficult to detect due to the presence of inhibitor(s) and the level of the inhibitor(s) may vary depending upon pathological conditions. We have found that urine from three patients with monocytic leukemia (M5) contained high levels of inhibitor(s) of MCF/II-1, whereas urine of normal subjects did not contain significant amounts. Urine from two patients with other blood neoplasic diseases also contained little inhibitory activity. The MCF/IL-1 inhibitor(s), which also acts on human recombinant IL-1 ft, is -25-35 kD, is not retained on concanavalin A-Sepharose column and can be partially destroyed with urea and boiling. At this stage of the purification the fraction containing the MCF/IL-1 inhibitor(s) also inhibits the LAF/IL-1 assay. However, this inhibitor(s) is probably distinct from other inhibitors already described
Features of the ancestral bilaterian inferred from Platynereis dumerilii ParaHox genes
Background The ParaHox gene cluster is the evolutionary sister to the Hox cluster. Whilst the role of the Hox cluster in patterning the anterior-posterior axis of bilaterian animals is well established, and the organisation of vertebrate Hox clusters is intimately linked to gene regulation, much less is known about the more recently discovered ParaHox cluster. ParaHox gene clustering, and its relationship to expression, has only been described in deuterostomes. Conventional protostome models (Drosophila melanogaster and Caenorhabditis elegans) are secondarily derived with respect to ParaHox genes, suffering gene loss and cluster break-up. Results We provide the first evidence for ParaHox gene clustering from a less-derived protostome animal, the annelid Platynereis dumerilii. Clustering of these genes is thus not a sole preserve of the deuterostome lineage within Bilateria. This protostome ParaHox cluster is not entirely intact however, with Pdu-Cdx being on the opposite end of the same chromosome arm from Pdu-Gsx and Pdu-Xlox. From the genomic sequence around the P. dumerilii ParaHox genes the neighbouring genes are identified, compared with other taxa, and the ancestral arrangement deduced. Conclusion We relate the organisation of the ParaHox genes to their expression, and from comparisons with other taxa hypothesise that a relatively complex pattern of ParaHox gene expression existed in the protostome-deuterostome ancestor, which was secondarily simplified along several invertebrate lineages. Detailed comparisons of the gene content around the ParaHox genes enables the reconstruction of the genome surrounding the ParaHox cluster of the protostome-deuterostome ancestor, which existed over 550 million years ago.Publisher PDFPeer reviewe
Cost-Effectiveness of Web-Based Patient-Reported Outcome Surveillance in Patients With Lung Cancer
Introduction: A multicenter randomized clinical trial in France found an overall survival benefit of web-based patient-reported outcome (PRO)–based surveillance after initial treatment for lung cancer compared with conventional surveillance. The aim of this study was to assess the cost-effectiveness of this PRO-based surveillance in lung cancer patients. Methods: This medico-economic analysis used data from the clinical trial, augmented by abstracted chart data and costs of consultations, imaging, transportations, information technology, and treatments. Costs were calculated based on actual reimbursement rates in France, and health utilities were estimated based on scientific literature review. Willingness-to-pay thresholds of €30,000 per quality-adjusted life year (QALY) and €90,000 per QALY were used to define a very cost-effective and cost-effective strategy, respectively. Average annual costs of experimental and control surveillance approaches were calculated. The incremental cost-effectiveness ratio was expressed as cost per life-year gained and QALY gained, from the health insurance payer perspective. One-way and multivariate probabilistic sensitivity analyses were performed. Results: Average annual cost of surveillance follow-up was €362 lower per patient in the PRO arm (€941/year/patient) compared to control (€1,304/year/patient). The PRO approach presented an incremental cost-effectiveness ratio of €12,127 per life-year gained and €20,912 per QALY gained. The probabilities that the experimental strategy is very cost-effective and cost-effective were 97% and 100%, respectively. Conclusions: Surveillance of lung cancer patients using web-based PRO reduced the follow-up costs. Compared to conventional monitoring, this surveillance modality represents a cost-effective strategy and should be considered in cancer care delivery
Expression of Distal-less, dachshund, and optomotor blind in Neanthes arenaceodentata (Annelida, Nereididae) does not support homology of appendage-forming mechanisms across the Bilateria
The similarity in the genetic regulation of
arthropod and vertebrate appendage formation has been
interpreted as the product of a plesiomorphic gene
network that was primitively involved in bilaterian
appendage development and co-opted to build appendages
(in modern phyla) that are not historically related
as structures. Data from lophotrochozoans are needed to
clarify the pervasiveness of plesiomorphic appendage forming
mechanisms. We assayed the expression of three
arthropod and vertebrate limb gene orthologs, Distal-less
(Dll), dachshund (dac), and optomotor blind (omb), in
direct-developing juveniles of the polychaete Neanthes
arenaceodentata. Parapodial Dll expression marks premorphogenetic
notopodia and neuropodia, becoming restricted
to the bases of notopodial cirri and to ventral
portions of neuropodia. In outgrowing cephalic appendages,
Dll activity is primarily restricted to proximal
domains. Dll expression is also prominent in the brain. dac
expression occurs in the brain, nerve cord ganglia, a pair
of pharyngeal ganglia, presumed interneurons linking a
pair of segmental nerves, and in newly differentiating
mesoderm. Domains of omb expression include the brain,
nerve cord ganglia, one pair of anterior cirri, presumed
precursors of dorsal musculature, and the same pharyngeal
ganglia and presumed interneurons that express dac.
Contrary to their roles in outgrowing arthropod and
vertebrate appendages, Dll, dac, and omb lack comparable
expression in Neanthes appendages, implying independent
evolution of annelid appendage development. We infer
that parapodia and arthropodia are not structurally or
mechanistically homologous (but their primordia might
be), that Dll’s ancestral bilaterian function was in sensory
and central nervous system differentiation, and that
locomotory appendages possibly evolved from sensory
outgrowths
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