356,665 research outputs found
A resampling-based test to detect person-to-person transmission of infectious disease
Early detection of person-to-person transmission of emerging infectious
diseases such as avian influenza is crucial for containing pandemics. We
developed a simple permutation test and its refined version for this purpose. A
simulation study shows that the refined permutation test is as powerful as or
outcompetes the conventional test built on asymptotic theory, especially when
the sample size is small. In addition, our resampling methods can be applied to
a broad range of problems where an asymptotic test is not available or fails.
We also found that decent statistical power could be attained with just a small
number of cases, if the disease is moderately transmissible between humans.Comment: Published at http://dx.doi.org/10.1214/07-AOAS105 in the Annals of
Applied Statistics (http://www.imstat.org/aoas/) by the Institute of
Mathematical Statistics (http://www.imstat.org
A Relational Approach to Quantum Mechanics, Part I: Formulation
Non-relativistic quantum mechanics is reformulated here based on the idea
that relational properties among quantum systems, instead of the independent
properties of a quantum system, are the most fundamental elements to construct
quantum mechanics. This idea, combining with the emphasis that measurement of a
quantum system is a bidirectional interaction process, leads to a new framework
to calculate the probability of an outcome when measuring a quantum system. In
this framework, the most basic variable is the relational probability
amplitude. Probability is calculated as summation of weights from the
alternative measurement configurations. The properties of quantum systems, such
as superposition and entanglement, are manifested through the rules of counting
the alternatives. Wave function and reduced density matrix are derived from the
relational probability amplitude matrix. They are found to be secondary
mathematical tools that equivalently describe a quantum system without
explicitly calling out the reference system. Schr\"{o}dinger Equation is
obtained when there is no entanglement in the relational probability amplitude
matrix. Feynman Path Integral is used to calculate the relational probability
amplitude, and is further generalized to formulate the reduced density matrix.
In essence, quantum mechanics is reformulated as a theory that describes
physical systems in terms of relational properties.Comment: 19 pages, 2 figures, article split into 3 parts during refereeing,
minor correction. Adding journal reference for part
Roles of tumor suppressors in regulating tumor-associated inflammation.
Loss or silencing of tumor suppressors (TSs) promotes neoplastic transformation and malignant progression. To date, most work on TS has focused on their cell autonomous effects. Recent evidence, however, demonstrates an important noncell autonomous role for TS in the control of tumor-associated inflammation. We review evidence from clinical data sets and mouse model studies demonstrating enhanced inflammation and altered tumor microenvironment (TME) upon TS inactivation. We discuss clinical correlations between tumor-associated inflammation and inactivation of TS, and their therapeutic implications. This review sets forth the concept that TS can also suppress tumor-associated inflammation, a concept that provides new insights into tumor-host interactions. We also propose that in some cases the loss of TS function in cancer can be overcome through inhibition of the resulting inflammatory response, regardless whether it is a direct or an indirect consequence of TS loss
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