The Experts below are selected from a list of 42081 Experts worldwide ranked by ideXlab platform

Shuai Huang - One of the best experts on this subject based on the ideXlab platform.

  • selective sensing of a Heterogeneous Population of units with dynamic health conditions
    IISE Transactions, 2018
    Co-Authors: Shuai Huang
    Abstract:

    AbstractMonitoring a large number of units whose health conditions follow complex dynamic evolution is a challenging problem in many healthcare and engineering applications. For instance, a unit ma...

  • A Collaborative Learning Framework for Estimating Many Individualized Regression Models in a Heterogeneous Population
    IEEE Transactions on Reliability, 2018
    Co-Authors: Eunshin Byon, Xiaoning Qian, Shuai Huang
    Abstract:

    Mixed-effect models (MEMs) have been found very useful for modeling complex dataset where many similar individualized regression models should be estimated. Like many statistical models, the success of these models builds on the assumption that a central tendency can effectively establish the Population-level characteristics and covariates are sufficient to characterize the individual variation as derivation from the center. In many real-world problems, however, the dataset is collected from a rather Heterogeneous Population, where each individual has a distinct model. To fill in this gap, we propose a collaborative learning framework that provides a generic methodology for estimating a Heterogeneous Population of individualized regression models by exploiting the idea of “canonical models” and model regularization. By using a set of canonical models to represent the Heterogeneous Population characteristics, the canonical models span the modeling space for the individuals' models, e.g., although each individual model is distinct, its model parameter vector can be represented by the parameter vectors of the canonical models. Theoretical analysis is also conducted to reveal a connection between the proposed method and the MEMs. Both simulation studies and applications on Alzheimer's disease and degradation modeling of turbofan engines demonstrate the efficacy of the proposed method.

Peter S Zammit - One of the best experts on this subject based on the ideXlab platform.

  • muscle satellite cells are a functionally Heterogeneous Population in both somite derived and branchiomeric muscles
    Developmental Biology, 2010
    Co-Authors: Luisa Boldrin, Paul Knopp, Jennifer E Morgan, Peter S Zammit
    Abstract:

    Skeletal muscles of body and limb are derived from somites, but most head muscles originate from cranial mesoderm. The resident stem cells of muscle are satellite cells, which have the same embryonic origin as the muscle in which they reside. Here, we analysed satellite cells with a different ontology, comparing those of the extensor digitorum longus (EDL) of the limb with satellite cells from the masseter of the head. Satellite cell-derived myoblasts from MAS and EDL muscles had distinct gene expression profiles and masseter cells usually proliferated more and differentiated later than those from EDL. When transplanted, however, masseter-derived satellite cells regenerated limb muscles as efficiently as those from EDL. Clonal analysis showed that functional properties differed markedly between satellite cells: ranging from clones that proliferated extensively and gave rise to both differentiated and self-renewed progeny, to others that divided minimally before differentiating completely. Generally, masseter-derived clones were larger and took longer to differentiate than those from EDL. This distribution in cell properties was preserved in both EDL-derived and masseter-derived satellite cells from old mice, although clones were generally less proliferative. Satellite cells, therefore, are a functionally Heterogeneous Population, with many occupants of the niche exhibiting stem cell characteristics in both somite-derived and branchiomeric muscles.

Cesar Alvarezgonzalez - One of the best experts on this subject based on the ideXlab platform.

  • cord blood lin cd45 embryonic like stem cells are a Heterogeneous Population that lack self renewal capacity
    PLOS ONE, 2013
    Co-Authors: Cesar Alvarezgonzalez, Richard Duggleby, Barbora Vagaska, Sergio Querol, Susana Gomez, Patrizia Ferretti, Alejandro Madrigal
    Abstract:

    Human umbilical cord blood (hUCB) has been proposed to contain not only haematopoietic stem cells, but also a rare pluripotent embryonic-like stem cell (ELSc) Population that is negative for hematopoietic markers (Lin−CD45−) and expresses markers typical of pluripotent cells. The aim of this work was to isolate, characterise and expand this ELSc fraction from hUCB, as it may provide a valuable cell source for regenerative medicine applications. We found that we could indeed isolate a Lin−CD45− Population of small cells (3–10 µm diameter) with a high nucleus to cytoplasm ratio that expressed the stem cell markers CD34 and CXCR4. However, in contrast to some previous reports, this fraction was not positive for CD133. Furthermore, although these cells expressed transcripts typical of pluripotent cells, such as SOX2, OCT3/4, and NANOG, they were not able to proliferate in any of the culture media known to support stem cell growth that we tested. Further analysis of the Lin−CD45− Population by flow cytometry showed the presence of a Lin−CD45−Nestin+ Population that were also positive for CD34 (20%) but negative for CXCR4. These data suggest that the Lin−CD45− stem cell fraction present in the cord blood represents a small Heterogeneous Population with phenotypic characteristics of stem cells, including a Lin−CD45−Nestin+ Population not previously described. This study also suggests that heterogeneity within the Lin−CD45− cell fraction is the likely explanation for differences in the hUCB cell Populations described by different groups that were isolated using different methods. These Populations have been widely called “embryonic-like stem cell” on the basis of their phenotypical similarity to embryonic stem cells. However, the fact they do not seem to be able to self-renew casts some doubt on their identity, and warns against defining them as “embryonic-like stem cell” at this stage.

Abdullah M Althiabi - One of the best experts on this subject based on the ideXlab platform.

  • Heterogeneous Population dynamics of active particles progression mutations and selection dynamics
    Mathematical Models and Methods in Applied Sciences, 2017
    Co-Authors: L Gibelli, A M Elaiw, Mohammed A Alghamdi, Abdullah M Althiabi
    Abstract:

    This paper proposes a conceptual revisiting of Population dynamics to include Heterogeneous behaviors of individuals, mutations, and selection. The first part of the paper focuses on the derivation of a general mathematical structure which permits to describe systems composed of individuals whose interactions are stochastic. Hybrid models where some of the Populations follow a deterministic dynamics are also discussed. The second part deals with two specific applications, namely the effect of the cellular aging in the virus infection process and the dynamics of virus mutation and competition with the immune system. Sample simulations are presented and classical models of Population dynamics are critically analyzed in light of the proposed approach.

Peter Kristensen - One of the best experts on this subject based on the ideXlab platform.

  • Selection of antibodies against a single rare cell present in a Heterogeneous Population using phage display
    Nature Protocols, 2011
    Co-Authors: Morten Dræby Sørensen, Peter Kristensen
    Abstract:

    Here we describe a new method applying phage-displayed antibody libraries to the selection of antibodies against a single identified cell on a glass slide. This is the only described method that has successfully achieved selection of antibodies against a single rare cell in a Heterogeneous Population of cells. The phage library is incubated with the slide containing the identified rare cell of interest; incubation is followed by UV irradiation while protecting the target cell with a minute disc. The UV light inactivates all phages outside the shielded area by cross-linking the DNA constituting their genomes. The expected yield is between one and ten phage particles from a single cell selection. The encoded antibodies are subsequently produced monoclonally and tested for specificity. This method can be applied within a week to carry out ten or more individual cell selections. Including subsequent testing of antibody specificity, a specific antibody can be identified within 2 months.