Interoperable manufacturing knowledge systems

For many years now, the importance of semantic technologies, that provide a formal, logic-based route to sharing meaning, has been recognised as offering the potential to support interoperability across multiple-related applications and hence, drive manufacturing competitiveness in the digital manufacturing age. However, progress in support of manufacturing enterprise interoperability has tended to be limited to fairly narrow domains of applicability. This paper presents a progression of research and understanding, culminating in the work undertaken in the recent EU FLEXINET project, to develop a comprehensive manufacturing reference ontology that can (a) support the clarification of understanding across domains, (b) support the ability to flexibly share information across interacting software systems and (c) provide the ability to readily configure company knowledge bases to support interoperable manufacturing systems.     

VerifyThis 2019: a program verification competition

VerifyThis is a series of program verification competitions that emphasize the human aspect: participants tackle the verification of detailed behavioral properties—something that lies beyond the capabilities of fully automatic verification and requires instead human expertise to suitably encode programs, specifications, and invariants. This paper describes the 8th edition of VerifyThis, which took place at ETAPS 2019 in Prague. Thirteen teams entered the competition, which consisted of three verification challenges and spanned 2 days of work. This report analyzes how the participating teams fared on these challenges, reflects on what makes a verification challenge more or less suitable for the typical VerifyThis participants, and outlines the difficulties of comparing the work of teams using wildly different verification approaches in a competition focused on the human aspect.

     

Assessment of the removal and inactivation of influenza viruses H5N1 and H1N1 by drinking water treatment

Since 2003, there has been significant concern about the possibility of an outbreak of avian influenza virus subtype H5N1. Moreover, in the last few months, a pandemic of a novel swine-origin influenza A virus, namely A(H1N1), has already caused hundreds of thousands of human cases of illness and thousands of deaths. As those viruses could possibly contaminate water resources through wild birds excreta or through sewage, the aim of our work was to find out whether the treatment processes in use in the drinking water industry are suitable for eradicating them. The effectiveness of physical treatments (coagulation-flocculation-settling, membrane ultrafiltration and ultraviolet) was assessed on H5N1, and that of disinfectants (monochloramine, chlorine dioxide, chlorine, and ozone) was established for both the H5N1 and H1N1 viruses.Natural water samples were spiked with human H5N1/H1N1 viruses. For the coagulation-settling experiments, raw surface water was treated in jar-test pilots with 3 different coagulating agents (aluminum sulfate, ferric chloride, aluminum polychorosulfate). Membrane performance was quantified using a hollow-fiber ultrafiltration system. Ultraviolet irradiation experiments were conducted with a collimated beam that made it possible to assess the effectiveness of various UV doses (25-60 mJ/cm²). In the case of ozone, 0.5 mg/L and 1 mg/L residual concentrations were tested with a contact time of 10 min. Finally, for chlorine, chlorine dioxide and monochloramine treatments, several residual oxidant target levels were tested (from 0.3 to 3 mg/L) with contact times of 5-120 min. The infectivity of the H5N1 and H1N1 viruses in water samples was quantified in cell culture using a microtiter endpoint titration.The impact of coagulation-settling on the H5N1 subtype was quite low and variable. In contrast, ultrafiltration achieved more than a 3-log reduction (and more than a 4-log removal in most cases), and UV treatment was readily effective on its inactivation (more than a 5-log inactivation with a UV dose of 25 mJ/cm²). Of the chemical disinfection treatments, ozone, chlorine and chlorine dioxide were all very effective in inactivating H5N1 and H1N1, whereas monochloramine treatment required higher doses and longer contact times to achieve significant reductions.Our findings suggest that the water treatment strategies that are currently used for surface water treatment are entirely suitable for removing and/or inactivating influenza A viruses. Appropriate preventive actions can be defined for single disinfection treatment plants.     

Ecological risk assessment of lead contamination at rifle and pistol ranges using techniques to account for site characteristics

Spent ammunition at outdoor rifle and pistol (RP) firing ranges creates a characteristic pattern of contamination, whereby small areas surrounding backstop berms exhibit extremely high soil lead (Pb) concentrations. We characterized sources, pathways and uncertainty in contaminant accumulation for receptors at two RP ranges in southeastern Ontario. Based on these results, we performed risk calculations using kriging to estimate risk across "worst-case" species foraging ranges. Range-normalized hazard quotients (RNHQ) were then calculated to estimate risk across each receptor's foraging range. Monte Carlo simulation was used to provide +2 standard deviation (SD) risk estimates, in order to account for uncertainty in risk parameters. The American robin was found to be most at risk (RNHQ=4.10; +2SD=9.24), followed by the short-tailed shrew (RNHQ=0.113; +2SD=0.243) and the eastern cottontail (RNHQ=0.109; +2SD=0.703). Elevated risk for the American robin and short-tailed shrew was due to their small foraging ranges and habit of eating earthworms, which bioaccumulate Pb. Elevated risk for the eastern cottontail was due to vegetation accumulating Pb to levels that were considerably higher than conventional bioaccumulation models would indicate. The results of this study clearly emphasize the importance of specific characteristics of RP ranges, such as contamination patterns, dust accumulation on plant tissues, and contaminant bioaccessibility. These characteristics should be accounted for, not only in performing risk assessments, but also in choosing remedial options and in routine management practices.     

Overview of the beam emission spectroscopy diagnostic system on the National Spherical Torus Experiment

A beam emission spectroscopy (BES) system has been installed on the National Spherical Torus Experiment (NSTX) to study ion gyroscale fluctuations. The BES system measures D(α) emission from a deuterium neutral heating beam. The system includes two optical views centered at r/a≈0.45 and 0.85 and aligned to magnetic field pitch angles at the neutral beam. f/1.5 collection optics produce 2-3 cm spot sizes at the neutral beam. The initial channel layout includes radial arrays, poloidal arrays, and two-dimensional grids. Radial arrays provide coverage from r/a≈0.1 to beyond the last-closed flux surface. Photodetectors and digital filters provide high-sensitivity, low-noise measurements at frequencies of up to 1 MHz. The BES system will be a valuable tool for investigating ion gyroscale turbulence and Alfve?n/energetic particle modes on NSTX.     

Portable fiber sensors based on surface-enhanced Raman scattering

Two portable molecular sensing systems based on surface-enhanced Raman scattering (SERS) have been experimentally demonstrated using either a tip-coated multimode fiber (TCMMF) or a liquid core photonic crystal fiber (LCPCF) as the SERS probe. With Rhodamine 6G as a test molecule, the TCMMF-portable SERS system achieved 2-3 times better sensitivity than direct sampling (focusing the laser light directly into the sample without the fiber probe), and a highly sensitive LCPCF-portable SERS system reached a sensitivity up to 59 times that of direct sampling, comparable to the sensitivity enhancement achieved using fiber probes in the bulky Renishaw system. These fiber SERS probes integrated with a portable Raman spectrometer provide a promising scheme for a compact and flexible molecular sensing system with high sensitivity and portability.     

Comparison of functional connectivity in default mode and sensorimotor networks at 3 and 7T

Object

The objective of this work was to assess functional connectivity measurements at ultra-high field (7T), given BOLD contrast to noise ratio increases with magnetic field strength but physiological noise also increases.

Materials and methods

Resting state BOLD data were acquired at 3 and 7T to assess connectivity in the sensorimotor network (SMN) and default mode network (DMN) at different spatial smoothing levels.

Results

At 3 and 7T positive correlation is observed between a right sensorimotor seed and left sensorimotor cortex. For the DMN, a seed in posterior cingulate cortex results in a high correlation in inferior parietal lobes and medial prefrontal cortex. We show higher temporal correlation coefficients for both the SMN and DMN at 7T compared to 3T for all smoothing levels. A spatial correlation between connectivity maps revealed no significant differences for the SMN, whilst the DMN showed increased spatial correlation dependent on SNR. The maximum physiological noise contribution was found to be higher at 7T, but noise in both seed and network nodes was not significantly increased, as shown by no significant difference in the spatial correlation of maps following physiological correction.

Conclusion

7T can improve spatial specificity of connectivity maps and facilitate measurement of connectivity in areas of lower intrinsic network correlation.     

Zebrafish Motile Cilia as a Model for Primary Ciliary Dyskinesia

Zebrafish is a vertebrate teleost widely used in many areas of research. As embryos, they develop quickly and provide unique opportunities for research studies owing to their transparency for at least 48 h post fertilization. Zebrafish have many ciliated organs that include primary cilia as well as motile cilia. Using zebrafish as an animal model helps to better understand human diseases such as Primary Ciliary Dyskinesia (PCD), an autosomal recessive disorder that affects cilia motility, currently associated with more than 50 genes. The aim of this study was to validate zebrafish motile cilia, both in mono and multiciliated cells, as organelles for PCD research. For this purpose, we obtained systematic high-resolution data in both the olfactory pit (OP) and the left–right organizer (LRO), a superficial organ and a deep organ embedded in the tail of the embryo, respectively. For the analysis of their axonemal ciliary structure, we used conventional transmission electron microscopy (TEM) and electron tomography (ET). We characterised the wild-type OP cilia and showed, for the first time in zebrafish, the presence of motile cilia (9 + 2) in the periphery of the pit and the presence of immotile cilia (still 9 + 2), with absent outer dynein arms, in the centre of the pit. In addition, we reported that a central pair of microtubules in the LRO motile cilia is common in zebrafish, contrary to mouse embryos, but it is not observed in all LRO cilia from the same embryo. We further showed that the outer dynein arms of the microtubular doublet of both the OP and LRO cilia are structurally similar in dimensions to the human respiratory cilia at the resolution of TEM and ET. We conclude that zebrafish is a good model organism for PCD research but investigators need to be aware of the specific physical differences to correctly interpret their results.     

Monolithic integration of microfluidic channels, liquid-core waveguides, and silica waveguides on silicon

The fabrication of embedded microchannels monolithically integrated with optical waveguides by plasma-enhanced chemical vapor deposition of doped silica glass is reported. Both waveguide ridges and template ridges for microchannel formation are patterned in a single photolithography step. The microchannels are formed within an overlay of borophosphosilicate glass (BPSG), which also serves as the top cladding layer of the silica waveguides. No top sealing of the channels is required. Surface accessible fluid input ports are formed in a BPSG layer, with no additional steps, by appropriate design of template layers. By tightly controlling the refractive index of the waveguide layer and the microchannel-forming layer, fully integrated structures facilitating optical coupling between solid waveguides and liquids segments in various geometries are demonstrated. Applications in liquid-filled photonic device elements for novel nonlinear optical devices and in optical sensors and on-chip spectroscopy are outlined.     

High-throughput and high-resolution flow cytometry in molded microfluidic devices

We describe the design, fabrication, and operation of two types of flow cytometers based on microfluidic devices made of a single cast of poly(dimethylsiloxane). The stream of particles or cells injected into the devices is hydrodynamically focused in both transverse and lateral directions, has a uniform velocity, and has adjustable diameter and shape. The cytometry system built around the first microfluidic device has fluorescence detection accuracy comparable with that of a commercial flow cytometer and can analyze as many as 17 000 particles/s. This high-throughput microfluidic device could be used in inexpensive stand-alone cytometers or as a part of integrated microanalysis systems. In the second device, a stream of particles is focused to a flow layer of a submicrometer thickness that allows imaging the particles with a high numerical aperture microscope objective. To take long-exposure, low-light fluorescence images of live cells, the device is placed on a moving stage, which accurately balances the translational motion of particles in the flow. The achieved resolution is comparable to that of still micrographs. This high-resolution device could be used for analysis of morphology and fluorescence distribution in cells in continuous flow.