Fractality of tics as a quantitative assessment tool for Tourette syndrome

Tics manifest as brief, purposeless and unintentional movements or noises that, for many individuals, can be suppressed temporarily with effort. Previous work has hypothesized that the chaotic temporal nature of tics could possess an inherent fractality, that is, have neighbour-to-neighbour correlation at all levels of timescale. However, demonstrating this phenomenon has eluded researchers for more than two decades, primarily because of the challenges associated with estimating the scale-invariant, power law exponent—called the fractal dimension D_f—from fractional Brownian noise. Here, we confirm this hypothesis and establish the fractality of tics by examining two tic time series datasets collected 6–12 months apart in children with tics, using random walk models and directional statistics. We find that D_f is correlated with tic severity as measured by the YGTTS total tic score, and that D_f is a sensitive parameter in examining the effect of several tic suppression conditions on the tic time series. Our findings pave the way for using the fractal nature of tics as a robust quantitative tool for estimating tic severity and treatment effectiveness, as well as a possible marker for differentiating typical from functional tics.     

A cathode support structure for use in a magnetron oscillator experiment

A low temperature co-fired ceramic (LTCC) material system has been used to develop a protype field emission cathode structure for use in an experimental magnetron oscillator. The structure is designed for used with 30 gated field emission array (GFEA) die electrically connected through silver metal traces and electrical vias. To approximate a cylinder, the cathode structure (48 mm long and 13.7 mm in diameter) is comprised of 10 faceted plates which cover the GFEA dies. Slits in the facet plates allow electron injection. The GFEA die (3 mm × 8 mm) are placed in axial columns of 3 and spaced azimuthally around a cylindrical support structure in a staggered configuration resulting in 10 azimuthal locations. LTCC manufacturing techniques were developed in order to fabricate the newly designed cathode with seven layers wrapped to form the cylinder with electrical traces and vias. Two different cathode wrapping techniques and two different via filling techniques were studied and compared. Two different facet plate manufacturing techniques were studied. Finally, four different support stand configurations for firing the cylindrical structure were also compared with a square post stand having the best circularity and linearity measurements of the fired structure.     

Docosahexaenoic acid and other dietary polyunsaturated fatty acids suppress leukotriene synthesis by mouse peritoneal macrophages

The efficacy of individual ω-t-3 polyunsaturated fatty acids (PUFA) in altering eicosanoid synthesis in peritoneal macrophages was studied by feeding mice for 10 days a diet containing 2 wt% fat, which included 0.5 wt% ethyl esters of eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA) or linolenic acid (LNA). Upon stimulation with calcium ionophore A23187, macrophages from these animals produced significantly lower amounts of leukotriene C₄, leukotriene B₄ and 12-hydroxyeicosatetraenoic acid, prostaglandin E₂ and 6-keto prostaglandin F_1α compared with those obtained from animals on the diets containing olive oil or safflower oil. The decrease in leukotriene synthesis was similar in the animals fed DHA, EPA or LNA diets. This depression of eicosanoids by DHA and EPA was associated with decreased levels of arachidonic acid (AA); however, LA that altered eicosanoids did not have the same effect on AA levels.     

Stability of wood fast pyrolysis oil

This study evaluates the effects of storage conditions on physical and chemical properties of biomass fast pyrolysis oils exposed to elevated temperatures over extended periods of time. It was performed on oak pyrolysis oil generated in the NREL vortex reactor. Oil samples were stored at three temperatures: 37, 60 and 90°C in glass vessels. Properties of the oils were measured after hours of storage at 90°C, and after days or weeks at lower temperatures. Chemical changes in the oils were measured using GPC (molecular weight distribution) and FTIR spectroscopy. The oil remained a single phase throughout the studied conditions. Its pH was not affected by storage. The water content, viscosity and molecular weight of the oil increased with the time and temperature of storage. First-order reaction kinetics were successfully used to predict changes in molecular weight of the stored oil. FTIR provided evidence that etherification or esterification are mechanisms for condensation of the oil during storage.     

Interferometric measurement of instantaneous local heat transfer from a horizontally vibrating isothermal cylinder

Local instantaneous heat-transfer coefficients were measured for free convection from an isothermal cylinder vibrating sinusoidally in a horizontal plane. The results show that the heat-transfer coefficient is strongly dependent upon the ratio of amplitude of vibration to cylinder diameter, $\text{A}\text{D}$. For values of $\text{A}\text{D}$less than approximately 0·25, a critical vibration intensity was observed below which vibration caused only small increases in the heat-transfer rate; however, at $\text{A}\text{D}$ greater than 0·25, the critical vibrational intensity did not appear to exist because the heat transfer from the cylinder increased as soon as the vibrational speed increased from zero. A correlation of the data is presented which predicts the increase in average heat transfer from the cylinder to air above the free convective rate.The correlation also applies to data for much larger vibrational intensities.     

丹尼尔斯大厦 加拿大多伦多

正多伦多大学丹尼尔斯建筑、景观和设计学院的设计采用了分期的方法,包括修复和扩建以前称为知识学院的标志性建筑,将现有建筑物改造成与教学和需求更相关的框架体系。这个十九世纪遗址的总体规划是通过对预期用途模式和场地生态的分析而制定的,目的是重新定位校园西南角与安大略湖的轴线,并为学院创造新的特性。丹尼尔斯建筑、景观和设计学院需要一个可持续发展的新型工     

A Step toward Molecular Evolution of RNA: Ribose Binds to Prebiotic Fatty Acid Membranes,and Nucleosides Bind Better than Individual Bases Do

A major challenge in understanding how biological cells arose on the early Earth is explaining how RNA and membranes originally colocalized. We propose that the building blocks of RNA (nucleobases and ribose) bound to self-assembled prebiotic membranes. We have previously demonstrated that the bases bind to membranes composed of a prebiotic fatty acid, but evidence for the binding of sugars has remained a technical challenge. Here, we used pulsed-field gradient NMR spectroscopy to demonstrate that ribose and other sugars bind to membranes of decanoic acid. Moreover, the binding of some bases is strongly enhanced when they are linked to ribose to form a nucleoside or – with the addition of phosphate – a nucleotide. This enhanced binding could have played a role in the molecular evolution leading to the production of RNA.     

News: "Greener" dry-cleaning alternative pushed by industry, environmental groups

Technology.     

Bacterial Killing by Light‐Triggered Release of Silver from Biomimetic Metal Nanorods

Illumination of noble metal nanoparticles at the plasmon resonance causes substantial heat generation, and the transient and highly localized temperature increases that result from this energy conversion can be exploited for photothermal therapy by plasmonically heating gold nanorods (NRs) bound to cell surfaces. Here, plasmonic heating is used for the first time to locally release silver from gold core/silver shell (Au@Ag) NRs targeted to bacterial cell walls. A novel biomimetic method of preparing Au@Ag core–shell NRs is employed, involving deposition of a thin organic polydopamine (PD) primer onto Au NR surfaces, followed by spontaneous electroless silver metallization, and conjugation of antibacterial antibodies and passivating polymers for targeting to gram‐negative and gram‐positive bacteria. Dramatic cytotoxicity of S. epidermidis and E. coli cells targeted with Au@Ag NRs is observed upon exposure to light as a result of the combined antibacterial effects of plasmonic heating and silver release. The antibacterial effect is much greater than with either plasmonic heating or silver alone, implying a strong therapeutic synergy between cell‐targeted plasmonic heating and the associated silver release upon irradiation. The findings suggest a potential antibacterial use of Au@Ag NRs when coupled with light irradiation, which has not been previously described.