Modified superposition: A simple time series approach to closed-loop manual controller identification

Single-channel pilot manual control output in closed-tracking tasks is modeled in terms of linear discrete transfer functions which are parsimonious and guaranteed stable. The transfer functions are found by applying a modified super-position time series generation technique. A Levinson-Durbin algorithm is used to determine the filter which prewhitens the input and a projective (least squares) fit of pulse response estimates is used to guarantee identified model stability. Results from two case studies are compared to previous findings, where the source of data are relatively short data records, approximately 25 seconds long. Time delay effects and pilot seasonalities are discussed and analyzed. It is concluded that single-channel time series controller modeling is feasible on short records, and that it is important for the analyst to determine a criterion for best time domain fit which allows association of model parameter values, such as pure time delay, with actual physical and physiological constraints. The purpose of the modeling is thus paramount

Effectiveness and Limitations of Unsupervised Home-Based Balance Rehabilitation with Nintendo Wii in People with Multiple Sclerosis

Balance training represents a critical part of the rehabilitation process of individuals living with multiple sclerosis (MS) since impaired postural control is a distinctive symptom of the disease. In recent years, the use of the Nintendo Wii system has become widespread among rehabilitation specialists for this purpose, but few studies have verified the effectiveness of such an approach using quantitative measures of balance. In this study, we analyzed the postural sway features of a cohort of twenty-seven individuals with MS before and after 5 weeks of unsupervised home-based balance training with the Wii system. Center of pressure (COP) time-series were recorded using a pressure platform and processed to calculate sway area, COP path length, displacements, and velocities in mediolateral (ML) and anteroposterior (AP) directions. Although the results show a significant reduction in sway area, COP displacements, and velocity, such improvements are essentially restricted to the ML direction, as the Wii platform appears to properly stimulate the postural control system in the frontal plane but not in the sagittal one. Available Wii games, although somewhat beneficial, appear not fully suitable for rehabilitation in MS owing to scarce flexibility and adaptability to MS needs and thus specific software should be developed

Surface finishes by mechanically induced wood surface fusion

Mechanically induced vibration wood fusion welding techniques can also be used to obtain wood surface finishes of increased surface hardness and performance in presence of polymerizing unsaturated oils such as sunflower oil, or other polymerizing finishes. Wood surface hardness values more than double than those for the untreated control timber can be obtained by this method. This result is obtained due to two effects induced by the sharp increase in temperature induced by the mechanical welding vibration (i) the polymerization to a hardened network of the unsaturated oil and (ii) the densification proven to occur in the surface layer of the timber during mechanically-induced vibration-welding. The first of these effects predominates at shorter welding times while at slightly longer welding times both effects occur with the second one progressively becoming the bigger contributor. In the latter case the some μm thin densified surface is a surface composite formed by the networked unsaturated oil permeating the wood fibre/fused lignin composite. © Springer-Verlag 2005

Aedesin : structure and antimicrobial activity against multidrug resistant bacterial strains

Multidrug resistance, which is acquired by both Gram-positive and Gram-negative bacteria, causes infections that are associated with significant morbidity and mortality in many clinical settings around the world. Because of the rapidly increasing incidence of pathogens that have become resistant to all or nearly all available antibiotics, there is a need for a new generation of antimicrobials with a broad therapeutic range for specific applications against infections. Aedesin is a cecropin-like anti-microbial peptide that was recently isolated from dengue virus-infected salivary glands of the Aedes aegypti mosquito. In the present study, we have refined the analysis of its structural characteristics and have determined its antimicrobial effects against a large panel of multidrug resistant bacterial strains, directly isolated from infected patients. Based the results from nuclear magnetic resonance spectroscopy analysis, Aedesin has a helix-bend-helix structure typical for a member of the family of α-helix anti-microbial peptides. Aedesin efficiently killed Gram-negative bacterial strains that display the most worrisome resistance mechanisms encountered in the clinic, including resistance to carbapenems, aminoglycosides, cephalosporins, 4th generation fluoroquinolones, folate inhibitors and monobactams. In contrast, Gram-positive strains were insensitive to the lytic effects of the peptide. The anti-bacterial activity of Aedesin was found to be salt-resistant, indicating that it is active under physiological conditions encountered in body fluids characterized by ionic salt concentrations. In conclusion, because of its strong lytic activity against multidrug resistant Gram-negative bacterial strains displaying all types of clinically relevant resistance mechanisms known today, Aedesin might be an interesting candidate for the development of alternative treatment for infections caused by these types of bacteria

SDSS-HET Survey of Kepler Eclipsing Binaries. Description of the Survey and First Results

The Kepler mission has provided a treasure trove of eclipsing binaries (EBs), observed at extremely high photometric precision, nearly continuously for several years. We are carrying out a survey of ~100 of these EBs to derive dynamical masses and radii with precisions of 3% or better. We use multiplexed near-infrared H-band spectroscopy from the Sloan Digital Sky Survey-III and -IV APOGEE instrument and optical spectroscopy from the Hobby–Eberly Telescope High-resolution Spectrograph to derive double-lined spectroscopic orbits and dynamical mass ratios (q) for the EB sample, two of which we showcase in this paper. This orbital information is combined with Kepler photometry to derive orbital inclination, dynamical masses of the system components, radii, and temperatures. These measurements are directly applicable for benchmarking stellar models that are integrating the next generation of improvements, such as the magnetic suppression of convection efficiency, updated opacity tables, and fine-tuned equations of state. We selected our EB sample to include systems with low-mass (M ≾ 0.8 M⊙) primary or secondary components, as well as many EBs expected to populate the relatively sparse parameter space below ~0.5 M⊙. In this paper, we describe our EB sample and the analytical techniques we are utilizing, and also present masses and radii for two systems that inhabit particularly underpopulated regions of mass–radius–period space: KIC 2445134 and KIC 3003991. Our joint spectroscopic and photometric analysis of KIC 2445134 (q = 0.411 ± 0.001) yields masses and radii of M_A = 1.29 ± 0.03 M⊙, M_B = 0.53 ± 0.01 M⊙, R_A = 1.42 ± 0.01 R⊙, R_B = 0.510 ± 0.004 R⊙, and a temperature ratio of T_B/T_A = 0.635 ± 0.001; our analysis of KIC 3003991 (q = 0.298 ± 0.006) yields M_A = 0.74 ± 0.04 M⊙, M_B = 0.222 ± 0.007 M⊙, R_A = 0.84 ± 0.01 R⊙, R_B = 0.250 ± 0.004 R⊙, and a temperature ratio of T_B/T_A = 0.662 ± 0.001

The effect of modafinil on the rat dopamine transporter and dopamine receptors D1–D3 paralleling cognitive enhancement in the radial arm maze

A series of drugs have been reported to increase memory performance modulating the dopaminergic system and herein modafinil was tested for its working memory (WM) enhancing properties. Reuptake inhibition of dopamine, serotonin (SERT) and norepinephrine (NET) by modafinil was tested. Sixty male Sprague–Dawley rats were divided into six groups (modafinil-treated 1–5–10 mg/kg body weight, trained and untrained and vehicle treated trained and untrained rats; daily injected intraperitoneally for a period of 10 days) and tested in a radial arm maze (RAM), a paradigm for testing spatial WM. Hippocampi were taken 6 h following the last day of training and complexes containing the unphosphorylated or phosphorylated dopamine transporter (DAT-CC and pDAT-CC) and complexes containing the D1–3 dopamine receptor subunits (D1–D3-CC) were determined. Modafinil was binding to the DAT but insignificantly to SERT or NET and dopamine reuptake was blocked specifically (IC50 = 11.11 μM; SERT 1547 μM; NET 182 μM). From day 8 (day 9 for 1 mg/kg body weight) modafinil was decreasing WM errors (WMEs) in the RAM significantly and remarkably at all doses tested as compared to the vehicle controls. WMEs were linked to the D2R-CC and the pDAT-CC. pDAT and D1–D3-CC levels were modulated significantly and modafinil was shown to enhance spatial WM in the rat in a well-documented paradigm at all the three doses and dopamine reuptake inhibition with subsequent modulation of D1–3-CC is proposed as a possible mechanism of action. © 2015 Karabacak, Sase, Aher, Sase, Saroja, Cicvaric, Höger, Berger, Bakulev, Sitte, Leban, Monje and Lubec