Chlamydial pneumonia of infancy: further clinical observations

Two patients with chlamydial pneumonia of infancy are described. One recovered spontaneously without any specific antichlamydial treatment. The other, prior to a belated antimicrobial therapy, developed a persistent and protracted respiratory illness characterized by wheezing. Our observations suggest that: (1) untreated chlamydial pneumonia of infancy may spontaneously resolve, or may become a persistent and protracted disease, and (2) wheezing may be a very prominent manifestation of the disease and should be differentiated from wheezing due to bronchiolitis and bronchial asthma.     

Operant escape learning in decerebrate duck embryos.

Trained 192 Peking duck embryos (Anas platythynchos) in an operant escape task on Day 25 of incubation (total incubation period of 27 days) following decerebration on Day 24. Experimental embryos successfully acquired the operant response, which involved the performance of a discrete foot flexion to terminate a shock applied to the wing. The decerebrate embryos resembled normal unoperated embryos of this age in their acquisition of the operant behavior. Results demonstrate that this form of learning can be acquired without benefit of telencephalic structures, at least at this point in development. Differences in the consequences of decerebration during prenatal or neonatal vs adult stages are discussed. (13 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Analysis of time-gated imaging through scattering media by a Fourier optics approach

The method of Fourier optics is applied to the problem of time-gated imaging through scattering media. Tb adapt the problem to this treatment, appropriate alterations are made: The continuous medium is replaced by a cascade of thin scatterers, and a spatial filtering process is substituted for the conventional gating processes. Closed-form solutions are derived.     

(Ba,Ca)TiO3 PTCR Ceramics with LaNiO3 Thin-Film Electrodes: Preparation and Characterization of the Interface

Conductive LaNiO₃ thin film electrodes were deposited by chemical solution deposition (CSD) from nitrate solutions onto polycrystalline Al₂O₃ and (Ba,Ca)TiO₃ PTCR ceramic substrates. The electrical properties of the LaNiO₃ thin film on Al₂O₃ and of the interface consisting of LaNiO₃ and the semiconductive oxide ceramic were investigated. The deposited LaNiO₃ films were about 250 nm thick and consisted of nanosized particles. The resistivity of the LaNiO₃ film was about 3 × 10^-3cm at 20°C. The PTCR ceramic consisted of m sized particles and exhibited an electronic resistivity of about 10 cm at 20°C and a steep increase of the resistivity of a few orders of magnitude above the Curie point at about 120°C. The electrical properties of the LaNiO₃/PTCR interface were dominated by the properties of a barrier layer between the PTCR ceramic and the LaNiO₃ electrode. The potential dependence of the impedance indicated that the barrier layer consisted of a depletion layer within the PTCR ceramic, when the flat band potential of LaNiO₃ on the PTCR ceramic at about –250 mV was exceeded. Additionally the formation of an insulating layer at the LaNiO₃ electrode has to be taken into account.     

Single-channel EEG measurement of engagement in virtual rehabilitation: a validation study

Virtual Reality - Stroke rehabilitation suffers from low levels of patient engagement, impeding recovery. Virtual rehabilitation (VR) approaches can improve patient outcomes; however, there is...     

Conditions for the equivalence between IQC and graph separation stability results

This paper provides a link between time-domain and frequency-domain stability results in the literature. Specifically, we focus on the comparison between stability results for a feedback interconnection of two nonlinear systems stated in terms of frequency-domain conditions. While the integral quadratic constrain (IQC) theorem can cope with them via a homotopy argument for the Lurye problem, graph separation results require the transformation of the frequency-domain conditions into truncated time-domain conditions. To date, much of the literature focuses on ‘hard’ factorisations of the multiplier, considering only one of the two frequency-domain conditions. Here it is shown that a symmetric, ‘doubly-hard’ factorisation is required to convert both frequency-domain conditions into truncated time-domain conditions. By using the appropriate factorisation, a novel comparison between the results obtained by IQC and separation theories is then provided. As a result, we identify under what conditions the IQC theorem may provide some advantage.     

Neural Networks Approach to the Random Walk Dilemma of Financial Time Series

Predictions of financial time series often show a characteristic one step shift relative to the original data as in a random walk. This has been the cause for opposing views whether such time series do contain information that can be extracted for predictions, or are simply random walks. In this case study, we show that NNs that are capable of extracting weak low frequency periodic signals buried in a strong high frequency signal, consistently predict the next value in the series to be the current value, as in a random walk, when used for one-step-ahead predictions of the detrended S&P 500 time series. In particular for the Time Delay Feed Forward Networks and Elman Networks of various configurations, our study supports the view of the detrended S&P 500 being a random walk series. This is consistent with the long standing hypothesis that some financial time series are random walk series.     

Output feedback and dynamical sliding-mode control of power converters

Using the underlying idea of the most widely accepted controller for power converters, the current-mode control, a new dynamical and sliding-mode control for dc–dc power converters, is proposed. The controller requires only voltage measurements; is easy to design; is robust under load and input voltage variations, exhibits fast response and does not depend on the load (although a knowledge of the load range is necessary to tune the controller). In spite of these features, it can be easily implemented using standard electronics components. The stability analysis is carried out using the discontinuous (large signal) nonlinear model. This analysis provides a set of controller admissible parameters to keep closed-loop system stability.     

Wetting of the (0001) <Emphasis Type="Italic">α</Emphasis>-Al<Subscript>2</Subscript>O<Subscript>3</Subscript> Sapphire Surface by Molten Aluminum: Effect of Surface Roughness

The wetting of molten aluminum on the “c”-plane (0001) of single-crystal α-Al₂O₃ (sapphire) was studied by the sessile drop technique from 800 °C (1073 K) to 1200 °C (1473 K). Systematically increasing the (0001) surface roughness by SiC abrasion increased the wetting contact angle, resulting in reduced wetting. The surface roughness factor R originally defined by Wenzel, was determined as a function of the abrasion, temperature, and time. The wetting decreases as the surface roughness increases. Rough surfaces also create time and temperature effects on wetting, changing those for a smoothly polished surface. The existence of a high-temperature surface structural transition for (0001) of α-Al₂O₃, which has been previously suggested, was confirmed. Increased roughness R accents the effect of the surface structural transition, increasing the wetting contact angle changes during the transition.