Effect of mechanical shear on the thin‐film properties of base oil‐polymer mixtures

The thickness and frictional characteristics of thin lubricant films are known to affect the fuel economy properties of oils. The base oil and polymer compositions of the lubricant are generally considered to be critical chemical factors that can influence these thin‐film lubricant properties in new oils. However, it is important to produce lubricants with good fuel economy properties that are maintained after the lubricant is degraded. Lubricants in use can undergo oxidation and mechanical shear degradation. The effect of oxidation degradation on thin‐film physical properties has previously been studied. This paper investigates the effect of mechanical shearing on thin‐film properties. Dispersant olefin copolymers are found to reduce thin‐film friction in simple mixtures and in fully formulated oils. In simple mixtures, shearing the dispersant olefin copolymers does not affect the friction‐reducing ability of these polymers. In fully formulated oils, even though shearing diminishes to a degree the friction‐reducing ability of dispersant olefin copolymers, these copolymers can still provide significant friction reduction.     

Exploiting a novel algorithm and GPUs to break the ten quadrillion pairwise comparisons barrier for time series motifs and joins

Time series motifs are approximately repeated subsequences found within a longer time series. They have been in the literature since 2002, but recently they have begun to receive significant attention in research and industrial communities. This is perhaps due to the growing realization that they implicitly offer solutions to a host of time series problems, including rule discovery, anomaly detection, density estimation, semantic segmentation, summarization, etc. Recent work has improved the scalability so exact motifs can be computed on datasets with up to a million data points in tenable time. However, in some domains, for example seismology or climatology, there is an immediate need to address even larger datasets. In this work, we demonstrate that a combination of a novel algorithm and a high-performance GPU allows us to significantly improve the scalability of motif discovery. We demonstrate the scalability of our ideas by finding the full set of exact motifs on a dataset with one hundred and forty-three million subsequences, which is by far the largest dataset ever mined for time series motifs/joins; it requires ten quadrillion pairwise comparisons. Furthermore, we demonstrate that our algorithm can produce actionable insights into seismology and ethology.     

Time-dependent changes of inflammatory mediators in the lungs of humans exposed to 0.4 ppm ozone for 2 hr: a comparison of mediators found in bronchoalveolar lavage fluid 1 and 18 hr after exposure

Acute exposure of humans to ozone results in reversible respiratory function decrements and cellular and biochemical changes leading to the production of substances which can mediate inflammation and acute lung injury. While pulmonary function decrements occur almost immediately after ozone exposure, it is not known how quickly the cellular and biochemical changes indicative of inflammation occur in humans. Increased bronchoalveolar lavage (BAL) fluid levels of neutrophils (PMNs) and prostaglandins (PGE2) have been reported in humans as early as 3 hr and as late as 18 hr after exposure. The purpose of this study was to determine whether a broad range of inflammatory mediators are elevated in BAl fluid within 1 hr of exposure. We exposed eight healthy volunteers twice: once to 0.4 ppm ozone and once to filtered air. Each exposure lasted for 2 hr during which the subjects underwent intermittent heavy exercise (66 liters/min). BAL was performed 1 hr after the exposure. Ozone induced rapid increases in PMNs, total protein, LDH, alpha-1 antitrypsin, fibronectin, PGE2, thromboxane B2, C3a, tissue factor, and clotting factor VII. In addition, there was a decrease in the recovery of total cells and alveolar macrophages, and decreased ability of alveolar macrophages to phagocytize Candida albicans. A comparison of these changes with changes observed in an earlier study in which subjects underwent BAL 18 hr after an identical exposure regimen indicates that IL-6 and PGE2 levels were higher 1 hr after exposure than 18 hr after exposure, fibronectin and tissue-plasminogen activator levels were higher 18 hr after exposure, and that PMNs, protein, and C3a were present at essentially the same levels at both times. These results indicate that (i) several inflammatory mediators are already elevated 1 hr after exposure; (ii) some mediators achieve their maximal levels in BAL fluid at different times following exposure. These data suggest that the inflammatory response is complex, depending on a cascade of timed events, and that depending on the mediator of interest one must choose an appropriate sampling time.     

Immediate addition to acrylic partial dentures

The conventional method of adding teeth to an existing prosthesis has the disadvantage that patients must be without their dentures while the teeth are added. Whilst a new immediate denture avoids this, it means that the patient will have to grow accustomed to the shape of a new polished surface. The method described in this paper eliminates these problems by making an immediate addition to the existing partial denture. Additionally, the technique has been found to be beneficial to those patients who are unable to tolerate conventional impression taking procedures.     

Collagen bundle morphometry in skin and scar tissue: a novel distance mapping method provides superior measurements compared to Fourier analysis

Histopathological evaluations of fibrotic processes require the characterization of collagen morphology in terms of geometrical features such as bundle orientation thickness and spacing. However, there are currently no reliable and valid techniques of measuring bundle thickness and spacing. Hence, two objective methods quantifying the collagen bundle thickness and spacing were tested for their reliability and validity: Fourier first-order maximum analysis and Distance Mapping, with the latter constituting a newly developed morphometric technique. Histological slides were constructed and imaged from 50 scar and 50 healthy human skin biopsies and subsequently analyzed by two observers to determine the interobserver reliability via the intraclass correlation coefficient. An intraclass correlation coefficient larger than 0.7 is considered as representing good reliability. The interobserver reliability for the Fourier first-order maximum and for the Distance Mapping algorithms, respectively, showed an intraclass correlation coefficient above 0.72 and 0.89. Additionally, we performed an assessment of validity in the form of responsiveness, in particular, demonstrating medium to excellent results via a calculation of the effect size, highlighting that both methods are sensitive enough to measure a treatment effect in clinical practice. In summary, two reliable and valid measurement methods were demonstrated for collagen bundle morphometry for the first time. Due to its superior reliability and more useful measures (bundle thickness and bundle spacing), Distance Mapping emerges as the preferred and more practical method. Nevertheless, in the future, both methods can be used for reliable and valid collagen morphometry of skin and scars, whereas further applications evaluating the quantitative microscopy of other fibrotic processes are anticipated.     

Scaling and time warping in time series querying

The last few years have seen an increasing understanding that dynamic time warping (DTW), a technique that allows local flexibility in aligning time series, is superior to the ubiquitous Euclidean distance for time series classification, clustering, and indexing. More recently, it has been shown that for some problems, uniform scaling (US), a technique that allows global scaling of time series, may just be as important for some problems. In this work, we note that for many real world problems, it is necessary to combine both DTW and US to achieve meaningful results. This is particularly true in domains where we must account for the natural variability of human actions, including biometrics, query by humming, motion-capture/animation, and handwriting recognition. We introduce the first technique which can handle both DTW and US simultaneously, our techniques involve search pruning by means of a lower bounding technique and multi-dimensional indexing to speed up the search. We demonstrate the utility and effectiveness of our method on a wide range of problems in industry, medicine, and entertainment.     

Type inference in flexible model-driven engineering using classification algorithms

Software and Systems Modeling - Flexible or bottom-up model-driven engineering (MDE) is an emerging approach to domain and systems modelling. Domain experts, who have detailed domain knowledge,...     

3D-ICONS: Digitizing Cultural Heritage Structures

As a partner in the EU co-funded 3D-ICONS project, the Discovery Programme has surveyed a wide range of the iconic cultural heritage sites in Ireland. This project aimed to establish a complete pipeline for the production of 3D replicas of archaeological monuments and historic buildings, and to publish the content to Europeana for public access. Challenges discussed include: making such high resolution data sets available to the public to enable online interaction and via the web, creating suitable and representative metadata and IPR frameworks for 3D cultural heritage data.