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This paper presents the development of a comprehensive self-assessment safety culture toolkit for the U.S. offshore oil and gas industry. Safety culture impacts organizational safety performance. Measuring safety culture will help an organization better understand the room for safety improvement. The major components of this toolkit are safety culture surveys, interviews, site safety walkthroughs, a review of previous incident investigations, a review of potential leading indicators (accident precursors), and a Safety and Environmental Management System (SEMS) review. This multi-component toolkit is expected to allow a comprehensive assessment of the offshore safety culture at single or multiple facilities. With careful wording of survey questions, safety culture surveys can provide insight into employee perceptions of safety. The paper discusses how safety culture surveys can be incorporated with all other key components to give a more complete picture of an organization's safety culture. A safety maturity model is proposed to incorporate the results from these safety culture measurements to describe an organization's safety maturity level. Like many safety maturity models, the model in this toolkit describes the safety culture maturity in a range from a reaction to events to continual improvement. The analysis of crucial safety culture-related assessment components supports the identification of a safety culture maturity level. [ABSTRACT FROM AUTHOR]

Highlights: [•] Mine and Mill costs for a giving mining operation are approximately equal. [•] Mining techniques influence the distribution of mine operating costs. [•] Savings in milling costs will significantly affect total mine operating cost. [•] Coarse particle flotation may reduce the impact of mill costs. [Copyright &y& Elsevier]

Abstract: Non-negative matrix factorization (NMF) has been proposed as a mathematical tool for identifying the components of a dataset. However, popular NMF algorithms tend to operate slowly and do not always identify the components which are most representative of the data. In this paper, an alternative algorithm for performing NMF is developed using the geometry of the problem. The computational costs of the algorithm are explored, and it is shown to successfully identify the components of a simulated dataset. The development of the geometric algorithm framework illustrates the ill-posedness of the NMF problem and suggests that NMF is not sufficiently constrained to be applied successfully outside of a particular class of problems. [Copyright &y& Elsevier]

Abstract: Earthworm (Lumbricidae) populations were assessed in three replicated, field experiments with different management intensities conducted on grassland research farms on medium-textured mineral soils, located at Solohead (Co. Tipperary), Grange (Co. Meath) and Johnstown Castle (Co. Wexford), Ireland. The experiment at Solohead involved four levels of mineral fertilizer application (80, 175, 225 and 350kgNha−1), and the plots were rotationally grazed by dairy cows. Three levels of mineral fertilizer application were compared at Johnstown Castle (0, 225 and 390kgNha−1) and two at Grange (100 and 225kgNha−1), and the plots at these sites were rotationally grazed by suckler cows and followers or dry cattle. Between 10 and 15 earthworm species were recorded per site, with Allolobophora chlorotica and Aporrectodea caliginosa being dominant. Other abundant species included Aporrectodea rosea, Aporrectodea longa, Lumbricus terrestris, Lumbricus friendi, Lumbricus festivus, Lumbricus rubellus and Satchellius mammalis. Mean earthworm population densities per treatment ranged from 203 to 324individualsm−2 and biomass from 60 to 176gm−2. ANCOVA revealed significant overall positive relationships between management intensity (as indicated by N application rate) and earthworm abundance (F =4.47, p <0.05) and biomass (F =17.32, p <0.001). While there was considerable variation in earthworm response to treatments both within and between sites, populations were not adversely affected by intensive management in any of the sites. It appears that any adverse effect of trampling at higher stocking rates was more than compensated for by increased food supply in the form of dung and plant litter. The presence of high earthworm populations is potentially an important factor in counteracting adverse impacts of intensive grazing on pasture soils, especially on heavy soils liable to poaching. [Copyright &y& Elsevier]

Summary: Current knowledge of earthworm feeding ecology is reviewed, with particular reference to food selection, ingestion, digestion and assimilation, and the use of novel techniques to advance understanding of the functional significance of these processes. Traditional research methods including direct observation of feeding behaviour, gut content analysis, choice tests, and litter bags have provided a wealth of information on earthworm feeding. However, there is a lack of the mechanistic, quantitative information required to characterise adequately their functional role in soil ecosystem processes such as soil C sequestration and loss, decomposition of organic residues, the maintenance of soil structure and trophic interactions with plants and microorganisms. Stable isotope ratio analysis of light elements (C, N, and S) offers a powerful research tool to reveal and quantify trophic relationships of earthworms in soil food webs, while molecular techniques can further enhance understanding of the interactions between earthworms and microorganisms and their functional significance. [Copyright &y& Elsevier]

In this paper we explore a recent iterative compression technique called non-negative matrix factorization (NMF). Several special properties are obtained as a result of the constrained optimization problem of NMF. For facial images, the additive nature of NMF results in a basis of features, such as eyes, noses, and lips. We explore various methods for efficiently computing NMF, placing particular emphasis on the initialization of current algorithms. We propose using Spherical K-Means clustering to produce a structured initialization for NMF. We demonstrate some of the properties that result from this initialization and develop an efficient way of choosing the rank of the low-dimensional NMF representation. [Copyright &y& Elsevier]

More research is required to validate and refine natural abundance stable isotope ratio techniques as a tool for the investigation of the feeding ecology of soil animals and trophic relations in soil food webs. Isotope ratios of C (δ13C) and N (δ15N) were measured in herbivorous and detritivorous invertebrate groups, namely lumbricid earthworms (7 species), enchytraeid worms (3 species), slugs (3 taxa), and their potential food sources in an arable system. Intrapopulation δ15N variation in the slug Deroceras reticulatum (n=52) was large (range 4.2‰), possibly reflecting spatial variability in the food sources. Significant correlations between C:N ratios and isotope ratios in earthworms suggest that factors other than feeding may influence isotopic patterns. One enchytraeid species, Enchytraeus buchholzi, was enriched in 13C and strongly depleted in 15N compared to all other groups. Invertebrates formed a continuum when considered in relation to C and N separately, but fell into two distinct groups on the basis of combined C and N isotope ratios. The less enriched group represents herbivorous and litter-feeding species, while the more enriched group represents soil feeders. It is concluded that δ13C measurements could provide a means of assigning separate baseline δ15N values to primary and secondary decomposers, which in turn could improve the inference of higher trophic levels, omnivory and intraguild predation. [Copyright &y& Elsevier]

The impact of intensive cultivation for potato production on the earthworm populations was assessed in two adjacent large field plots. Three successive winter wheat crops had been grown in one plot while winter wheat was grown with minimum cultivation in an understorey of white clover in the other. Both plots were ploughed in spring 1998 and intensively cultivated (grubbing, ridging, bed-tilling, destoning, ridging) prior to planting potatoes. Earthworm populations were reduced from a mean density of 319 individuals m–2 and 55 g m–2 biomass in the conventional wheat plot, and from 1160 individuals and 175 g m–2 biomass in the wheat–clover plot in the 1996/1997 cropping season, to 40–82 individuals and 4–19 g m–2 in June–October 1998 following potato planting. Populations declined to virtually undetectable levels following mechanical potato harvesting in late autumn 1998 and spring cultivation for barley in 1999, remained at very low levels throughout 1999 and had shown no sign of recovering by May 2000. The results show that earthworm populations can be virtually eliminated within a single season by drastic forms of soil cultivation. [Copyright &y& Elsevier]

Background Electroencephalography (EEG) invariably contains extra-cranial artifacts that are commonly dealt with based on qualitative and subjective criteria. Failure to account for EEG artifacts compromises data interpretation. New Method We have developed a quantitative and automated support vector machine (SVM)-based algorithm to accurately classify artifactual EEG epochs in awake rodent, canine and humans subjects. An embodiment of this method also enables the determination of ‘eyes open/closed’ states in human subjects. Results The levels of SVM accuracy for artifact classification in humans, Sprague Dawley rats and beagle dogs were 94.17%, 83.68%, and 85.37%, respectively, whereas 'eyes open/closed' states in humans were labeled with 88.60% accuracy. Each of these results was significantly higher than chance. Comparison with Existing Methods Other existing methods, like those dependent on Independent Component Analysis, have not been tested in non-human subjects, and require full EEG montages, instead of only single channels, as this method does. Conclusions We conclude that our EEG artifact detection algorithm provides a valid and practical solution to a common problem in the quantitative analysis and assessment of EEG in pre-clinical research settings across evolutionary spectra. [ABSTRACT FROM AUTHOR]

We evaluated a 32-year-old woman whose oculocutaneous albinism (OCA), bleeding diathesis, neutropenia, and history of recurrent infections prompted consideration of the diagnosis of Hermansky-Pudlak syndrome type 2. This was ruled out because of the presence of platelet δ-granules and absence of AP3B1 mutations. As parental consanguinity suggested an autosomal recessive mode of inheritance, we employed homozygosity mapping, followed by whole-exome sequencing, to identify two candidate disease-causing genes, SLC45A2 and G6PC3. Conventional dideoxy sequencing confirmed pathogenic mutations in SLC45A2, associated with OCA type 4 (OCA-4), and G6PC3, associated with neutropenia. The substantial reduction of SLC45A2 protein in the patient's melanocytes caused the mislocalization of tyrosinase from melanosomes to the plasma membrane and also led to the incorporation of tyrosinase into exosomes and secretion into the culture medium, explaining the hypopigmentation in OCA-4. Our patient's G6PC3 mRNA expression level was also reduced, leading to increased apoptosis of her fibroblasts under endoplasmic reticulum stress. To our knowledge, this report describes the first North American patient with OCA-4, the first culture of human OCA-4 melanocytes, and the use of homozygosity mapping, followed by whole-exome sequencing, to identify disease-causing mutations in multiple genes in a single affected individual. [ABSTRACT FROM AUTHOR]