Estimating Structural Change with Smooth Transition Regressions: an Application to Meat Demand

This paper explores the role of structural change in systems of demand equations. Specifically, we adapt the time—varying regression framework of Lin and Teräsvirta (1994), which in turn is related to the dynamic smooth transition models introduced by Teräsvirta (1994). Unlike previous efforts at modeling structural change in demand systems, we do not impose the nature of the change to be monotonic—several non-monotonic alternatives are considered. An application is presented using the Almost Ideal Inverse Demand System (IAIDS) applied to U.S. meat demand data, 1960-2004. Results show the importance of modeling structural change and that, moreover, the best-fitting model is associated with a form of symmetric, non-monotonic structural change.Inverse Almost Ideal Demand System; Meat Demand; Structural Change; Time-Varying Regression

Development of CNS-type Primitive Neuroectodermal Tumor in Metastatic Testicular Mixed Germ Cell Tumor.

A 29-year-old man presenting with a retroperitoneal mass was found to have a testis lesion consistent with mixed germ cell tumor and the RPLND specimen showed teratoma with an area of central nervous system-type primitive neuroectodermal tumor (PNET) not present in the testis. Whether such primitive tumor components represent a de novo tumor component or represent progression from existing neuroepithelial teratomatous elements is unclear. Given the high likelihood of residual tumor and possibility of malignant transformation, post-chemotherapy RPLND remains vital in treating patients with testis cancer. PNET is chemo-resistant and lesions should be resected, without clear evidence for adjuvant chemotherapy

A Wide Field, Low Frequency Radio Survey of the Field of M31: I. Construction and Statistical Analysis of the Source Catalog

We present here the results of a 325 MHz radio survey of M31, conducted with the A-configuration of the Very Large Array. The survey covered an area of 7.6 deg$^2$, and a total of 405 radio sources between \la6\arcsec and 170\arcsec in extent were mapped with a resolution of 6\arcsec and a 1$\sigma$ sensitivity of $\sim$0.6 \mjyb. For each source, its morphological class, major axis $\theta_M$, minor axis $\theta_m$, position angle $\theta_{PA}$, peak flux $I$, integrated flux density $S$, spectral index $\alpha$ and spectral curvature parameter $\phi$ were calculated. A comparison of the flux and radial distribution -- both in the plane of the sky and in the plane of M31 -- of these sources with those of the XMM--LSS and WENSS radio surveys revealed that a vast majority of sources detected are background radio galaxies. As a result of this analysis, we expect that only a few sources are intrinsic to M31. These sources are identified and discussed in an accompanying paper.Comment: 29 pages with 4 tables and 10 figures (JPEGs), accepted for publication in ApJS. Full-resolution images available on reques

Parametric Representation of Rank d Tensorial Group Field Theory: Abelian Models with Kinetic Term ∑s∣ps∣+μ\sum_{s}|p_s| + \mu

We consider the parametric representation of the amplitudes of Abelian models in the so-called framework of rank $d$ Tensorial Group Field Theory. These models are called Abelian because their fields live on $U(1)^D$. We concentrate on the case when these models are endowed with particular kinetic terms involving a linear power in momenta. New dimensional regularization and renormalization schemes are introduced for particular models in this class: a rank 3 tensor model, an infinite tower of matrix models $\phi^{2n}$ over $U(1)$, and a matrix model over $U(1)^2$. For all divergent amplitudes, we identify a domain of meromorphicity in a strip determined by the real part of the group dimension $D$. From this point, the ordinary subtraction program is applied and leads to convergent and analytic renormalized integrals. Furthermore, we identify and study in depth the Symanzik polynomials provided by the parametric amplitudes of generic rank $d$ Abelian models. We find that these polynomials do not satisfy the ordinary Tutte's rules (contraction/deletion). By scrutinizing the "face"-structure of these polynomials, we find a generalized polynomial which turns out to be stable only under contraction.Comment: 69 pages, 35 figure

Stable Electromyographic Sequence Prediction During Movement Transitions using Temporal Convolutional Networks

Transient muscle movements influence the temporal structure of myoelectric signal patterns, often leading to unstable prediction behavior from movement-pattern classification methods. We show that temporal convolutional network sequential models leverage the myoelectric signal's history to discover contextual temporal features that aid in correctly predicting movement intentions, especially during interclass transitions. We demonstrate myoelectric classification using temporal convolutional networks to effect 3 simultaneous hand and wrist degrees-of-freedom in an experiment involving nine human-subjects. Temporal convolutional networks yield significant $(p<0.001)$ performance improvements over other state-of-the-art methods in terms of both classification accuracy and stability.Comment: 4 pages, 5 figures, accepted for Neural Engineering (NER) 2019 Conferenc

Biocontrol of weedy Sporobolus grasses in Australia using fungal pathogens

In Australia there are five weedy Sporobolus grass (WSG) species that heavily impact agricultural industries and native biodiversity. WSG have been the subject of several efforts to find host-specific pathogens with potential for classical and inundative biocontrol. Most of these studies are only discussed in unpublished reports or theses, so in this paper we synthesise the available peer-reviewed and ‘grey’ literature that discuss classical, augmentative and inundative biocontrol of WSG in Australia using fungal pathogens. We consider the hundreds of fungal pathogens previously isolated from Sporobolus hosts on an international and national scale. Of the pathogens investigated for WSG biocontrol previously, the only promising classical biocontrol agent was a smut fungus (Ustilago sporoboli-indici) from South Africa that is now present in Queensland and New South Wales, Australia. Its method of introduction to Australia is unknown. We hence discuss the history and potential for augmentative biocontrol of WSG using U. sporoboli-indici. Next, we summarise inundative biocontrol efforts. Several ascomycetes isolated from Australian WSG populations have been tested in this regard, including species of Nigrospora, Fusarium, Curvularia, Microdochium, Pestalotiopsis, and Neopestalotiopsis. However, a lack of host-specificity or efficacy subsequently precluded their further development, and potential improvements on those inundative biocontrol studies are discussed. Finally, we discuss a collection of endemic fungal taxa isolated from diseased Sporobolus in Australia, which are currently undergoing virulence, pathogenicity, and host-specificity screening as potential inundative biocontrol agents for WSG. Our intention is that the lessons learned from previous studies and summarised herein, will support ongoing development of WSG biocontrol agents in Australia, and more broadly, weed biocontrol using plant pathogens anywhere in the world

Vortex Scattering and Intercommuting Cosmic Strings on a Noncommutative Spacetime

We study the scattering of noncommutative vortices, based on the noncommutative field theory developed in [Phys. Rev. D 75, 045009 (2007)], as a way to understand the interaction of cosmic strings. In the center-of-mass frame, the effects of noncommutativity vanish, and therefore the reconnection of cosmic strings occurs in an identical manner to the commutative case. However, when scattering occurs in a frame other than the center-of-mass frame, strings still reconnect but the well known 90-degree scattering no longer need correspond to the head on collision of the strings, due to the breakdown of Lorentz invariance in the underlying noncommutative field theory.Comment: 18 pages, 2 figure

Linear and Weakly Non-Linear Analyses of Gravity Modulation and Electric Field on the Onset of Rayleigh-Bénard Convection in a Micropolar Fluid

The effect of time periodic body force (or g-jitter or gravity modulation) on the onset of Rayleigh-B©nard electro-convention in a micropolar fluid layer is investigated by making linear and non-linear stability analysis. The stability of the horizontal fluid layer heated from below is examined by assuming time periodic body acceleration. This normally occurs in satellites and in vehicles connected with micro gravity simulation studies. A linear and non-linear analysis is performed to show that gravity modulation can significantly affect the stability limits of the system. The linear theory is based on normal mode analysis and perturbation method. Small amplitude of modulation is used to compute the critical Rayleigh number and wave number. The shift in the critical Rayleigh number is calculated as a function of frequency of modulation. The non-linear analysis is based on the truncated Fourier series representation. The resulting non-autonomous Lorenz model is solved numerically to quantify the heat transport. It is observed that the gravity modulation leads to delayed convection and reduced heat transport