Nonlinear Taylor rules: evidence from a large dataset

In this paper we estimate nonlinear Taylor rules over the 1986-2008 sample time period and augment the traditional Taylor rule by including principal components to better model Federal Reserve policy. Including principal components is useful in that they extract information about the overall economy from multiple economic indicators in a statistically optimal way. Additionally, given that uncertainty may influence Federal Reserve decisions, we incorporate an uncertainty index in the reaction function of the Federal Reserve. We find substantial evidence that the Federal Reserve responded to increases in macroeconomic uncertainty by cutting the Federal Funds rate over the sample period. We also find evidence that the Federal Reserve responded aggressively to increases in capacity utilization, especially when the inflation rate was above 2%

Mannual of CATUR : Devanagari Edition (An invitation to desk top publishing)

Differentially expressed cellular components. (XLSX 25 kb

An unobserved components model that yields business and medium-run cycles

We generalize the unobserved components (UC) model to allow the permanent component to have different dynamics than the transitory components when decomposing U.S. economic activity using a multivariate UC model of (log) output, consumption, and investment. We find that these proposed dynamics in the permanent component are statistically significant and distinct from those of the transitory components. Our approach provides an alternative explanation for the growth cycles identified by Comin and Gertler (2006) that is related to the cyclical movements in technology, in a framework consistent with the Beveridge and Nelson (1981) decomposition

Pattern Selection in Network of Coupled Multi-Scroll Attractors

<div><p>Multi-scroll chaotic attractor makes the oscillator become more complex in dynamic behaviors. The collective behaviors of coupled oscillators with multi-scroll attractors are investigated in the regular network in two-dimensional array, which the local kinetics is described by an improved Chua circuit. A feasible scheme of negative feedback with diversity is imposed on the network to stabilize the spatial patterns. Firstly, the Chua circuit is improved by replacing the nonlinear term with Sine function to generate infinite aquariums so that multi-scroll chaotic attractors could be generated under appropriate parameters, which could be detected by calculating the Lyapunov exponent in the parameter region. Furthermore, negative feedback with different gains (<i>D</i>₁, <i>D</i>₂) is imposed on the local square center area A₂ and outer area A₁ of the network, it is found that spiral wave, target wave could be developed in the network under appropriate feedback gain with diversity and size of controlled area. Particularly, homogeneous state could be reached after synchronization by selecting appropriate feedback gain and controlled size in the network. Finally, the distribution for statistical factors of synchronization is calculated in the two-parameter space to understand the transition of pattern region. It is found that developed spiral waves, target waves often are associated with smaller factor of synchronization. These results show that emergence of sustained spiral wave and continuous target wave could be effective for further suppression of spatiotemporal chaos in network by generating stable pacemaker completely.</p></div

Uncovering a Dynamic Feature of the Transcriptional Regulatory Network for Anterior-Posterior Patterning in the <i>Drosophila</i> Embryo

<div><p>Anterior-posterior (AP) patterning in the <i>Drosophila</i> embryo is dependent on the Bicoid (Bcd) morphogen gradient. However, most target genes of Bcd also require additional inputs to establish their expression domains, reflective of the operation of a cross-regulatory network and contributions of other maternal signals. This is in contrast to <i>hunchback</i> (<i>hb</i>), which has an anterior expression domain driven by an enhancer that appears to respond primarily to the Bcd input. To gain a better understanding of the regulatory logic of the AP patterning network, we perform quantitative studies that specifically investigate the dynamics of <i>hb</i> transcription during development. We show that Bcd-dependent <i>hb</i> transcription, monitored by the intron-containing nascent transcripts near the P2 promoter, is turned off quickly–on the order of a few minutes–upon entering the interphase of nuclear cycle 14A. This shutdown contrasts with earlier cycles during which active <i>hb</i> transcription can persist until the moment when the nucleus enters mitosis. The shutdown takes place at a time when the nuclear Bcd gradient profile in the embryo remains largely intact, suggesting that this is a process likely subject to control of a currently unknown regulatory mechanism. We suggest that this dynamic feature offers a window of opportunity for <i>hb</i> to faithfully interpret, and directly benefit from, Bcd gradient properties, including its scaling properties, to help craft a robust AP patterning outcome.</p></div

Spatial point pattern of nuclear transcriptional states.

<p>Shown is an embryo with nuclei masked according to <i>hb</i> transcriptional states, i.e., the number of <i>hb</i> intron dots detected. Blue: 0-dot nuclei; green: 1-dot nuclei; red: 2-dot nuclei; black: nuclei with over 2 dots. (B) is the cropped experimental field from the solid square in (A). See <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0060876#pone.0060876.s001" target="_blank">Figure S1</a> for locations of the experimental fields in all 14 embryos.</p

Formation of Circular Crack Pattern in Deposition Self-Assembled by Drying Nanoparticle Suspension

Curved cracks widely exist in nanoparticle (NP) deposition produced by drying colloidal suspension. Circular cracks, for example, initiate and propagate along a circular trajectory. One feasible theoretical explanation of a circular crack is the Xia-Hutchinson model, in which a preexisting track (flaw loop) in the film is necessary for initiating and propagating the crack on the circular path. Here, we report the first experimental evidence of dried deposition to support this model. Our results indicate that cracks along the circular trajectory can surprisingly “pass” across a 180 μm air gap. Moreover, two arc-path cracks originate in different areas and propagate to meet, forming a circular trajectory. These unexpected crack initiation and propagation indicate that the crack propagates alone the “preformed” track, experimentally confirming the hypothesis proposed by the Xia–Hutchinson model. The transition of the circular crack to a radial one indicates that the deposition microstructure is the dominant factor for the crack formation

Formation of target wave induced by ion channels blocking in potassium.

<p>The developed state (<i>t</i> = 800 time units) when some potassium ion channels in a square array (90≤<i>i</i> ≤100, 90≤<i>j</i> ≤100) are blocked at <i>x</i>_Ca = 1, coupling intensity <i>D</i> = 4, for <i>x</i>_k = 0.1 (panel a), <i>x</i>_k = 0.2 (panel b),<i>x</i>_k = 0.3 (panel c), <i>x</i>_k = 0.4 (panel d).</p

Intron staining detecting nascent transcripts near the <i>hb</i> P2 promoter.

<p>(<b>A</b>) Shown is a schematic diagram of the <i>hb</i> locus and the locations of the probes used in this study. P1 and P2 are two promoters for <i>hb</i> transcription leading to two types of transcripts, where exons are represented by boxes with coding regions filled in green and non-coding in grey; introns are represented by thin lines. The heavy blue line represents the probe for detecting the mature <i>hb</i> mRNA and the heavy red line represents the intronic probe. (<b>B</b>) Shown is a merged confocal image of an embryo at cycle 13. The detected nuclear envelope is shown in red and the nascent <i>hb</i> transcripts detected (with an intronic probe) as intron dots are in green. Scale bar, 50 µm. (<b>C</b>) Shown is a magnified view of a section of the expression region from panel <b>A</b>. (<b>E</b> and <b>F</b>) Shown are a merged confocal image (<b>E</b>) of an embryo in cycle 14A and a magnified view (<b>F</b>) of a section of the expression region from panel <b>C</b>.</p

Formation of spatial patterns.

<p><b>(a-d)</b> The developed spatial states with different conditions being used at <i>t</i> = 1000 time units; <b>(a)</b> stable target wave at <i>D</i>₁ = 0.2, <i>D</i>₂ = 0.5, <i>A</i>₂ = 11×11(90≤<i>i</i>, <i>j</i>≤100); <b>(b)</b> broken patterns at <i>D</i>₁ = 0.2, <i>D</i>₂ = 0.5, <i>A</i>₂ = 15×15; <b>(c)</b> stable target wave at <i>D</i>₁ = 0.1, <i>D</i>₂ = 0.4, A₂ = 15×15; <b>(d)</b> spiral wave at <i>D</i>₁ = 0.2, <i>D</i>₂ = 0.5, <i>A</i>₂ = 16×16 (90≤<i>i</i>, <i>j</i>≤105).</p