From Events to Reactions: A Progress Report

Syndicate is a new coordinated, concurrent programming language. It occupies a novel point on the spectrum between the shared-everything paradigm of threads and the shared-nothing approach of actors. Syndicate actors exchange messages and share common knowledge via a carefully controlled database that clearly scopes conversations. This approach clearly simplifies coordination of concurrent activities. Experience in programming with Syndicate, however, suggests a need to raise the level of linguistic abstraction. In addition to writing event handlers and managing event subscriptions directly, the language will have to support a reactive style of programming. This paper presents event-oriented Syndicate programming and then describes a preliminary design for augmenting it with new reactive programming constructs.Comment: In Proceedings PLACES 2016, arXiv:1606.0540

Reading and arithmetic in adolescents with autism spectrum disorders: Peaks and dips in attainment

In describing academic attainment in autism spectrum disorders (ASD), results are typically reported at the group mean level. This may mask subgroups of individuals for whom academic achievement is incommensurate with intellectual ability. The authors tested the IQ, literacy, and mathematical abilities of a large group (N = 100) of adolescents (14–16 years old) with ASD. Seventy-three percent of the sample had at least one area of literacy or mathematical achievement that was highly discrepant (approximately 14 standard score points) from full-scale IQ (FSIQ). The authors focused on four subgroups with either word reading (“Reading Peak” and “Reading Dip”) or arithmetic (“Arithmetic Peak” and “Arithmetic Dip”) higher or lower than FSIQ. These subgroups were largely mutually exclusive and were characterized by distinct intellectual profiles. The largest was the “Arithmetic Peak” subgroup of participants, who presented with average intellectual ability alongside superior arithmetic skills and who were predominantly in a mainstream educational setting. Overall, the most pervasive profile was discrepantly poor reading comprehension, which associated with severity of social and communication difficulties. The high rate of uneven academic attainment in ASD has implications for educational practice

Auditory Discrimination and Auditory Sensory Behaviours in Autism Spectrum Disorders

It has been hypothesised that auditory processing may be enhanced in autism spectrum disorders (ASD). We tested auditory discrimination ability in 72 adolescents with ASD (39 childhood autism; 33 other ASD) and 57 IQ and age-matched controls, assessing their capacity for successful discrimination of the frequency, intensity and duration differences in pairs of sounds.At the group level, auditory discrimination ability did not differ between the adolescents with and without ASD. However, we found a subgroup of 20% of individuals in the ASD group who showed ‘exceptional’ frequency discrimination skills (defined as 1.65 SDs above the control mean) and who were characterised by average intellectual ability and delayed language onset. Auditory sensory behaviours (i.e. behaviours in response to auditory sensory input) are common in ASD and we hypothesised that these would relate to auditory discrimination ability. For the ASD group, poor performers on the intensity discrimination task reported more auditory sensory behaviours associated with coping with loudness levels. Conversely, those who performed well on the duration discrimination task reported more auditory sensory behaviours across the full range measured. Frequency discrimination ability did not associate with auditory sensory behaviours. We therefore conclude that (i) enhanced frequency discrimination is present in around 1 in 5 individuals with ASD and may represent a specific phenotype; and (ii) individual differences in auditory discrimination ability in ASD may influence the expression of auditory sensory behaviours by modulating the degree to which sounds are detected or missed in the environment

Evaluation of a multi-point method for determining acoustic impedance

An investigation was conducted to explore potential improvements provided by a Multi-Point Method (MPM) over the Standing Wave Method (SWM) and Two-Microphone Method (TMM) for determining acoustic impedance. A wave propagation model was developed to model the standing wave pattern in an impedance tube. The acoustic impedance of a test specimen was calculated from a best fit of this standing wave pattern to pressure measurements obtained along the impedance tube centerline. Three measurement spacing distributions were examined: uniform, random, and selective. Calculated standing wave patterns match the point pressure measurement distributions with good agreement for a reflection factor magnitude range of 0.004 to 0.999. Comparisons of results using 2, 3, 6, and 18 measurement points showed that the most consistent results are obtained when using at least 6 evenly spaced pressure measurements per half-wavelength. Also, data were acquired with broadband noise added to the discrete frequency noise and impedances were calculated using the MPM and TMM algorithms. The results indicate that the MPM will be superior to the TMM in the presence of significant broadband noise levels associated with mean flow

Tony Lynn Jones in a Senior Baritone Recital

This is the program for the senior baritone recital of Tony Lynn Jones. Mr. Jones was accompanied on the piano by Susan Atkinson. This recital took place on April 29, 2002, in the McBeth Recital Hall in the Mabee Fine Arts Center

Fluctuating pressures measured beneath a high-temperature, turbulent boundary layer on a flat plate at Mach number of 5

Fluctuating pressures were measured beneath a Mach 5, turbulent boundary layer on a flat plate with an array of piezoresistive sensors. The data were obtained with a digital signal acquisition system during a test run of 4 seconds. Data sampling rate was such that frequency analysis up to 62.5 kHz could be performed. To assess in situ frequency response of the sensors, a specially designed waveguide calibration system was employed to measure transfer functions of all sensors and related instrumentation. Pressure time histories were approximated well by a Gaussian prohibiting distribution. Pressure spectra were very repeatable over the array span of 76 mm. Total rms pressures ranged from 0.0017 to 0.0046 of the freestream dynamic pressure. Streamwise, space-time correlations exhibited expected decaying behavior of a turbulence generated pressure field. Average convection speed was 0.87 of freestream velocity. The trendless behavior with sensor separation indicated possible systematic errors

Experimental validation of a two-dimensional shear-flow model for determining acoustic impedance

Tests were conducted to validate a two-dimensional shear-flow analytical model for determining the acoustic impedance of a liner test specimen in a grazing-incidence, grazing-flow environment. The tests were limited to a test specimen chosen to exhibit minimal effects of grazing flow so that the results obtained by using the shear-flow analytical model would be expected to match those obtained from normal-incidence impedance measurements. Impedances for both downstream and upstream sound propagation were generally consistent with those from normal-incidence measurements. However, sensitivity of the grazing-incidence impedance to small measurement or systematic errors in propagation constant varied dramatically over the range of test frequencies

Single-step flask to 250 L cell culture with a hybrid mixing single-use bioreactor

The process of scaling suspended cell cultures from frozen stocks through a large single-use bioreactor (SUB) includes numerous processing steps and operations. These steps, or seed train, involve vessel transfers and associated connections that increase the potential for contamination and human error. Of the multiple methods available for inoculating a 250 L SUB with sufficient cell quanitites, including multiple shake flasks, tabletop stirred tank bioreactor, or a 50L SUBs. Over the past decade tilting-type single-use bioreactor has been particularly attractive. Such wave-inducing systems implement tilting or rocking motion to agitate cultures which provides gas transfer and maintains cell suspension. Additionally, these rocking systems capitalize on single-use bioprocess containers (BPCs) which facilitate rapid deployment and cleanup when compared to reusable alternatives. Unfortunately, while rocking systems are simpler than other options, they still require connection and transfer steps. In an effort to further streamline the scale-up process, a tilting mechanism and bottom heating jacket have been added to a standard 250 L SUB to provide rocking motion and bottom temperature control to the BPC. This hybrid system can thus utilize rocking motion to mix small volumes of liquid (10-20L) and maintains standard impeller-based stirring functionality for volumes around 50 L and above. As designed, proliferating cells in 500 mL of media from flasks could be directly added to small volumes of media in the tilting SUB. Additional expansions with media addition are supported with rocking and bottom heating. An example expansion sequence would take cells in 500 mL media in a flask to 1.5 L of fresh media to form 2 L in the hybrid SUB. This would be followed by 8 L of fresh media addition after sufficient growth to form 10 L of media. 40 L of fresh media could then be added after cell growth and once media volume has reached 50 L. At this point, mixing via rocking will be discontinued and operation would follow well defined 5:1 turndown settings using a standard pitched blade impeller and drilled hole sparger (DHS) for the remaining SUB culture process. Currently, overhead gassing coupled with liquid rocking is used primarily for expanding cultures. As low cell density shake flask and scale-up process do not often feature active feedback control, future cell-specific processing could be optimized as the 250 L SUB already equipped with integrated monitoring and controls for gassing, mixing, pH, dO2, dCO2, cell mass, and/or other emerging process analytical technologies (PAT). Implementation of such a hybrid SUB would reduce expenses, manual operations, and potential risk of process contamination. The 250L working volume SUB cultured to high density is sufficient for seeding multiple 1000L or 2000L SUBs in a production environment using a 5:1 turn-down. Alternatively, this concept should be of particular interest to those possessing high productivity cell lines that have need to generate clinical grade and quantities of materials, while only investing in only one piece of bioreactor equipment or they desire a scale-up solution that optimizes limited facility work spac