Spliced DNA sequences in the Paramecium germline: their properties and evolutionary potential

Despite playing a crucial role in germline-soma differentiation, the evolutionary significance of developmentally regulated genome rearrangements (DRGRs) has received scant attention. An example of DRGR is DNA splicing, a process that removes segments of DNA interrupting genic and/or intergenic sequences. Perhaps, best known for shaping immune-system genes in vertebrates, DNA splicing plays a central role in the life of ciliated protozoa, where thousands of germline DNA segments are eliminated after sexual reproduction to regenerate a functional somatic genome. Here, we identify and chronicle the properties of 5,286 sequences that putatively undergo DNA splicing (i.e., internal eliminated sequences [IESs]) across the genomes of three closely related species of the ciliate Paramecium (P. tetraurelia, P. biaurelia, and P. sexaurelia). The study reveals that these putative IESs share several physical characteristics. Although our results are consistent with excision events being largely conserved between species, episodes of differential IES retention/excision occur, may have a recent origin, and frequently involve coding regions. Our findings indicate interconversion between somatic—often coding—DNA sequences and noncoding IESs, and provide insights into the role of DNA splicing in creating potentially functional genetic innovation

Measurement of the Noise Resulting from the Interaction of Turbulence with a Lifting Surface

An experimental study of the noise resulting from the interaction of an airfoil with incident turbulence is presented. The test models include NACA0015 airfoils of different chord lengths, a flat plate with a sharp leading edge, and an airfoil of same section as a reference Fowler flap. The airfoils are immersed in nearly isotropic turbulence. Two approaches for performing the noise measurements are used and compared. The effects that turbulence intensity and scales, airfoil geometry, velocity and angle of attack have on the incident turbulence interaction noise are examined. Detailed directivity measurements are presented. It is found that noise spectral levels beyond the peak frequency decrease more with decreasing airfoil leading edge sharpness, and that spectral peak level (at 0 deg. angle of attack) appears to be mostly controlled by the airfoil fs thickness and chord. Increase in turbulence scale and intensity are observed to lead to a uniform increase of the noise spectral levels with an LI(sup 2) dependence (where L is the turbulence longitudinal integral scale and I is the turbulence intensity). Noise levels are found to scale with the 6th power of velocity and the 2nd power of the airfoil chord. Sensitivity to changes in angle of attack appears to have a turbulence longitudinal integral scale to chord (C) ratio dependence, with large effects on noise for L/C greater than or equal to 1 and decreased effects as L/C becomes smaller than 1. For all L/C values, the directivity pattern of the noise resulting from the incident turbulence is seen to remain symmetric with respect to the direction of the mean flow until stall, at which point, the directivity becomes symmetric with respect to the airfoil chord. It is also observed that sensitivity to angle of attack changes is more pronounced on the model suction side than on the model pressure side, and in the higher frequency range of the spectra for the largest airfoils tested (L/C less than 0.24)

ANOPP Landing Gear Noise Prediction Comparisons to Model-scale Data

The NASA Aircraft NOise Prediction Program (ANOPP) includes two methods for computing the noise from landing gear: the "Fink" method and the "Guo" method. Both methods have been predominately validated and used to predict full-scale landing gear noise. The two methods are compared, and their ability to predict the noise for model-scale landing gear is investigated. Predictions are made using both the Fink and Guo methods and compared to measured acoustic data obtained for a high-fidelity, 6.3%-scale, Boeing 777 main landing gear. A process is developed by which full-scale predictions can be scaled to compare with model-scale data. The measurements were obtained in the NASA Langley Quiet Flow Facility for a range of Mach numbers at a large number of observer polar (flyover) and azimuthal (sideline) observer angles. Spectra and contours of the measured sound pressure levels as a function of polar and azimuthal angle characterize the directivity of landing gear noise. Comparisons of predicted noise spectra and contours from each ANOPP method are made. Both methods predict comparable amplitudes and trends for the flyover locations, but deviate at the sideline locations. Neither method fully captures the measured noise directivity. The availability of these measured data provides the opportunity to further understand and advance noise prediction capabilities, particularly for noise directivity

Carrying Little Sticks: Is There a ‘Deterrence Gap’ in Employment Standards Enforcement in Ontario, Canada?

This article assesses whether a deterrence gap exists in the enforcement of the Ontario Employment Standards Act (ESA), which sets minimum conditions of employment in areas such as minimum wage, overtime pay and leaves. Drawing on a unique administrative data set, the article measures the use of deterrence in Ontario’s ESA enforcement regime against the role of deterrence within two influential models of enforcement: responsive regulation and strategic enforcement. The article finds that the use of deterrence is below its prescribed role in either model of enforcement. We conclude that there is a deterrence gap in Ontario

Sensory and motor properties of bulboreticular and raphe neurons in awake and anesthetized cats

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/24587/1/0000870.pd

Improving Employment Standards and their Enforcement in Ontario: A Research Brief Addressing Options Identified in the Interim Report of the Changing Workplaces Review

The quality of employment available to Ontarians is a growing concern among legislators, policymakers, and the general public alike. There is widespread recognition that precarious employment and the challenges posed by the associated realignment of risks, costs and power relations between employees and employers require improvements to employees’ legislative protection. Ontario’s Changing Workplaces Review (CWR) affords us an opportunity to take stock of important changes taking place the province’s labour market. As the Terms of Reference introduced at the outset of the CWR note, “far too many workers are experiencing greater precariousness” in employment in Ontario today than in the recent past. Accordingly, with the aim of “creating decent work in Ontario, particularly [for] those who have been made vulnerable by changes in our economy and workplaces,” such terms directed the Special Advisors to investigate the dynamics underlying the magnitude of precariousness in the province’s labour market and to pose options for mitigating this fundamental social and economic problem through reforms to Ontario’s Labour Relations Act (LRA) and Employment Standards Act (ESA)

An unidentified Fermi source emitting radio bursts in the Galactic bulge

We report on the detection of radio bursts from the Galactic bulge using the real-time transient detection and localization system, realfast. The pulses were detected commensally on the Karl G. Jansky Very Large Array during a survey of unidentified Fermi $\gamma$-ray sources. The bursts were localized to subarcsecond precision using realfast fast-sampled imaging. Follow-up observations with the Green Bank Telescope detected additional bursts from the same source. The bursts do not exhibit periodicity in a search up to periods of 480s, assuming a duty cycle of < 20%. The pulses are nearly 100% linearly polarized, show circular polarization up to 12%, have a steep radio spectral index of -2.7, and exhibit variable scattering on timescales of months. The arcsecond-level realfast localization links the source confidently with the Fermi $\gamma$-ray source and places it nearby (though not coincident with) an XMM-Newton X-ray source. Based on the source's overall properties, we discuss various options for the nature of this object and propose that it could be a young pulsar, magnetar, or a binary pulsar system.Comment: Submitted to The Astrophysical Journa

Closing the Employment Standards Enforcement Gap, An Agenda for Change

Precarious employment is increasing in Ontario. A growing share of Ontario’s private sector employees earns low wages while a shrinking portion belongs to unions. These trends are fueled by changes in the structure of Ontario’s labour force. In many industries, including accommodation and food services, administrative services, and cleaning, workplaces are being transformed through greater use of contracting out, franchising, and extended supply chains. These ways of structuring work contribute to driving working conditions downward