94 research outputs found
Statistical Properties of the Interbeat Interval Cascade in Human Subjects
Statistical properties of interbeat intervals cascade are evaluated by
considering the joint probability distribution for two interbeat increments and of
different time scales and . We present evidence that the
conditional probability distribution
may obey a Chapman-Kolmogorov equation. The corresponding Kramers-Moyal (KM)
coefficients are evaluated. It is shown that while the first and second KM
coefficients, i.e., the drift and diffusion coefficients, take on well-defined
and significant values, the higher-order coefficients in the KM expansion are
very small. As a result, the joint probability distributions of the increments
in the interbeat intervals obey a Fokker-Planck equation. The method provides a
novel technique for distinguishing the two classes of subjects in terms of the
drift and diffusion coefficients, which behave differently for two classes of
the subjects, namely, healthy subjects and those with congestive heart failure.Comment: 5 pages, 6 figure
A Forward-Design Approach to Increase the Production of Poly-3-Hydroxybutyrate in Genetically Engineered Escherichia coli
Biopolymers, such as poly-3-hydroxybutyrate (P(3HB)) are produced as a carbon store in an array of organisms and exhibit characteristics which are similar to oil-derived plastics, yet have the added advantages of biodegradability and biocompatibility. Despite these advantages, P(3HB) production is currently more expensive than the production of oil-derived plastics, and therefore, more efficient P(3HB) production processes would be desirable. In this study, we describe the model-guided design and experimental validation of several engineered P(3HB) producing operons. In particular, we describe the characterization of a hybrid phaCAB operon that consists of a dual promoter (native and J23104) and RBS (native and B0034) design. P(3HB) production at 24 h was around six-fold higher in hybrid phaCAB engineered Escherichia coli in comparison to E. coli engineered with the native phaCAB operon from Ralstonia eutropha H16. Additionally, we describe the utilization of non-recyclable waste as a low-cost carbon source for the production of P(3HB)
Scale Invariance in the Nonstationarity of Physiological Signals
We introduce a segmentation algorithm to probe temporal organization of
heterogeneities in human heartbeat interval time series. We find that the
lengths of segments with different local values of heart rates follow a
power-law distribution. This scale-invariant structure is not a simple
consequence of the long-range correlations present in the data. We also find
that the differences in mean heart rates between consecutive segments display a
common functional form, but with different parameters for healthy individuals
and for patients with heart failure. This finding may provide information into
the way heart rate variability is reduced in cardiac disease.Comment: 13 pages, 5 figures, corrected typo
Building a global alliance of biofoundries (vol 10, 2040, 2019)
The original version of this Comment contained errors in the legend of Figure 2, in which the locations of the fifteenth and sixteenth GBA members were incorrectly given as '(15) Australian Genome Foundry, Macquarie University; (16) Australian Foundry for Advanced Biomanufacturing, University of Queensland.'. The correct version replaces this with '(15) Australian Foundry for Advanced Biomanufacturing (AusFAB), University of Queensland and (16) Australian Genome Foundry, Macquarie University'. This has been corrected in both the PDF and HTML versions of the Comment
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