Impact of Black Shale Weathering on Sediment Quality

Weathering of black shales leads to elevated metal concentrations in both surface water and stream sediments. In spite of the recent focus on black shales, few data exist on the ecological impacts of this process particularly on aquatic organisms. The key objective of this study was to determine the impact of trace metal concentrations in sediments upon aquatic organisms. To achieve the above objective, stream sediment samples were collected from streams draining black shale and limestone (used as a reference stream) lithologies located in central Arkansas between June 2003 and January 2004. Trace metal concentrations were measured by the dynamic reaction cell inductively coupled plasma mass spectrometry (ICPMS; Perkin Elmer DRC II) following EPA 6020 methodology. Sediment samples were tested for toxicity using standard EPA protocols. The trace metal concentrations in sediments and acute toxicity test findings using midge larvae, Chironomus tentans with endpoints measured as growth and survival is presented. Our results showed that there are significant differences in survival of the midge larvae among the study sites and also among the different sampling occasions. Percent survival of the midge larvae in the sediments derived from black shales was lower than that observed in the limestone-derived stream sediments. Significant differences in growth of the midge larvae were also observed among the sites with the control and reference stream sediments having higher growth than the black shale stream sediments. Though our measured metal concentrations in the black shale-derived sediments were below the Effects Range-Low, there is a great potential of metal accumulation in the fine sediment fraction particularly during baseflow regimes. At the time, metals can be concentrated in the fine sediment fraction due to the low discharge and less dilution. The study thus far has shown that the black shale metal-enriched stream sediments have both lethal and sublethal effects on aquatic organisms and higher organisms through food chain transfer

Marine Toads in the Wild

This is where the abstract of this record would appear. This is only demonstration data

A hemispherical, high-solid-angle optical micro-cavity for cavity-QED studies

We report a novel hemispherical micro-cavity that is comprised of a planar integrated semiconductor distributed Bragg reflector (DBR) mirror, and an external, concave micro-mirror having a radius of curvature $50\mathrm{\mu m}$. The integrated DBR mirror containing quantum dots (QD), is designed to locate the QDs at an antinode of the field in order to maximize the interaction between the QD and the cavity. The concave micro-mirror, with high-reflectivity over a large solid-angle, creates a diffraction-limited (sub-micron) mode-waist at the planar mirror, leading to a large coupling constant between cavity mode and QD. The half-monolithic design gives more spatial and spectral tuning abilities, relatively to fully monolithic structures. This unique micro-cavity design will potentially enable us to both reach the cavity quantum electrodynamics (QED) strong coupling regime and realize the deterministic generation of single photons on demand.Comment: 15 pages, 17 figures, final versio

Bacterial Mutagenicity of Urban Organic Aerosol Sources in Comparison to Atmospheric Samples

The bacterial mutagenicity of a comprehensive set of urban particulate air pollution source samples is examined using the Salmonella typhimurium forward mutation assay. Each of the combustion source samples examined, including the exhaust from catalyst-equipped autos, noncatalyst autos, heavy-duty diesel trucks, plus natural gas, distillate oil, and wood combustion sources, is mutagenic in this assay, with a response per microgram of organic carbon in these samples generally greater than that of cigarette smoke aerosol. The noncombustion source samples tested generally are not mutagenic at the levels examined. The specific mutagenicity (mutant fraction per microgram of organic carbon) of ambient aerosol samples collected in southern California is compared to a weighted average of the specific mutagenicity of the primary source samples assembled in proportion to their emission rates in the Los Angeles area. In most cases where a comparison can be made, the specific mutagenicity of the source composites and the ambient samples are of similar magnitude, with the exception that the -PMS mutagenicity of the aerosol at Long Beach, CA, during the first half of the calendar year 1982 and at Azusa, CA, during the April-June 1982 period is much higher than can be explained by direct emissions from the sources studied here

Analysis of ozone and nitric acid in spring and summer Arctic pollution using aircraft, ground-based, satellite observations and MOZART-4 model: source attribution and partitioning

In this paper, we analyze tropospheric O_3 together with HNO_3 during the POLARCAT (Polar Study using Aircraft, Remote Sensing, Surface Measurements and Models, of Climate, Chemistry, Aerosols, and Transport) program, combining observations and model results. Aircraft observations from the NASA ARCTAS (Arctic Research of the Composition of the Troposphere from Aircraft and Satellites) and NOAA ARCPAC (Aerosol, Radiation and Cloud Processes affecting Arctic Climate) campaigns during spring and summer of 2008 are used together with the Model for Ozone and Related Chemical Tracers, version 4 (MOZART-4) to assist in the interpretation of the observations in terms of the source attribution and transport of O_3 and HNO_3 into the Arctic (north of 60° N). The MOZART-4 simulations reproduce the aircraft observations generally well (within 15%), but some discrepancies in the model are identified and discussed. The observed correlation of O_3 with HNO_3 is exploited to evaluate the MOZART-4 model performance for different air mass types (fresh plumes, free troposphere and stratospheric-contaminated air masses). Based on model simulations of O_3 and HNO_3 tagged by source type and region, we find that the anthropogenic pollution from the Northern Hemisphere is the dominant source of O3 and HNO3 in the Arctic at pressures greater than 400 hPa, and that the stratospheric influence is the principal contribution at pressures less 400 hPa. During the summer, intense Russian fire emissions contribute some amount to the tropospheric columns of both gases over the American sector of the Arctic. North American fire emissions (California and Canada) also show an important impact on tropospheric ozone in the Arctic boundary layer. Additional analysis of tropospheric O_3 measurements from ground-based FTIR and from the IASI satellite sounder made at the Eureka (Canada) and Thule (Greenland) polar sites during POLARCAT has been performed using the tagged contributions. It demonstrates the capability of these instruments for observing pollution at northern high latitudes. Differences between contributions from the sources to the tropospheric columns as measured by FTIR and IASI are discussed in terms of vertical sensitivity associated with these instruments. The first analysis of O_3 tropospheric columns observed by the IASI satellite instrument over the Arctic is also provided. Despite its limited vertical sensitivity in the lowermost atmospheric layers, we demonstrate that IASI is capable of detecting low-altitude pollution transported into the Arctic with some limitations

Recovery-focused mental health care planning and co-ordination in acute inpatient mental health settings: a cross national comparative mixed methods study

BACKGROUND: Involving mental health service users in planning and reviewing their care can help personalised care focused on recovery, with the aim of developing goals specific to the individual and designed to maximise achievements and social integration. We aimed to ascertain the views of service users, carers and staff in acute inpatient wards on factors that facilitated or acted as barriers to collaborative, recovery-focused care. METHODS: A cross-national comparative mixed-methods study involving 19 mental health wards in six service provider sites in England and Wales. This included a survey using established standardised measures of service users (n = 301) and staff (n = 290) and embedded case studies involving interviews with staff, service users and carers (n = 76). Quantitative and qualitative data were analysed within and across sites using descriptive and inferential statistics, and framework method. RESULTS: For service users, when recovery-oriented focus was high, the quality of care was rated highly, as was the quality of therapeutic relationships. For staff, there was a moderate correlation between recovery orientation and quality of therapeutic relationships, with considerable variability. Staff members rated the quality of therapeutic relationships higher than service users did. Staff accounts of routine collaboration contrasted with a more mixed picture in service user accounts. Definitions and understandings of recovery varied, as did views of hospital care in promoting recovery. Managing risk was a central issue for staff, and service users were aware of measures taken to keep them safe, although their involvement in discussions was less apparent. CONCLUSIONS: There is positive practice within acute inpatient wards, with evidence of commitment to safe, respectful, compassionate care. Recovery ideas were evident but there remained ambivalence on their relevance to inpatient care. Service users were aware of efforts taken to keep them safe, but despite measures described by staff, they did not feel routinely involved in care planning or risk management decisions. Research on increasing therapeutic contact time, shared decision making in risk assessment and using recovery focused tools could further promote personalised and recovery-focused care planning. This paper arises from a larger study published by National Institute for Health Research (Simpson A, et al, Health Serv Deliv Res 5(26), 2017)

Seasonal and Spatial Variation of the Bacterial Mutagenicity of Fine Organic Aerosol in Southern California

The bacterial mutagenicity of a set of 1993 urban particulate air pollution samples is examined using the Salmonella typhimurium TM677 forward mutation assay. Ambient fine particulate samples were collected for 24 hr every sixth day throughout 1993 at four urban sites, including Long Beach, central Los Angeles, Azusa, and Rubidoux, California, and at an upwind background site on San Nicolas Island. Long Beach and central Los Angeles are congested urban areas where air quality is dominated by fresh emissions from air pollution sources; Azusa and Rubidoux are located farther downwind and receive transported air pollutants plus increased quantities of the products of atmospheric chemical reactions. Fine aerosol samples from Long Beach and Los Angeles show a pronounced seasonal variation in bacterial mutagenicity per cubic meter of ambient air, with maximum in the winter and a minimum in the summer. The downwind smog receptor site at Rubidoux shows peak mutagenicity (with postmitochondrial supernatant but no peak without postmitochondrial supernatant) during the September-October periods when direct transport from upwind sources can be expected. At most sites the mutagenicity per microgram of organic carbon from the aerosol is not obviously higher during the summer photochemical smog period than during the colder months. Significant spatial variation in bacterial mutagenicity is observed: mutagenicity per cubic meter of ambient air, on average, is more than an order of magnitude lower at San Nicolas Island than within the urban area. The highest mutagenicity values per microgram of organics supplied to the assay are found at the most congested urban sites at central Los Angeles and Long Beach. The highest annual average values of mutagenicity per cubic meter of air sampled occur at central Los Angeles. These findings stress the importance of proximity to sources of direct emissions of bacterial mutagens and imply that if important mutagen-forming atmospheric reactions occur, they likely occur in the winter and spring seasons as well as the photochemically more active summer and early fall periods

The moral muteness of managers: an Anglo-American phenomenon? German and British managers and their moral reasoning about environmental sustainability in business

Several studies in the Anglo-American context have indicated that managers present themselves as morally neutral employees who act only in the best interest of the company by employing objective skills. The reluctance of managers to use moral arguments in business is further accentuated in the now common argument presented as a neutral fact that the company must always prioritise shareholder value. These and other commercial aims are seen as an objective reality in business, whilst questions about sustainability, environmental problems or fair trade are seen as emotional or moral ones; a phenomenon described as ‘moral muteness’. This research explores whether this ‘moral muteness’ is an Anglo-American phenomenon and/or whether managers in other countries - in this case Germany - might express themselves in a different way. The focus is on moral arguments around environmental sustainability and the implications of this study for cross-cultural management. This article is based on a qualitative, comparative cross-cultural study of British and German managers in the Food Retail and Energy Sectors. In line with the studies mentioned above, British managers placed a strong emphasis on their moral neutrality. In contrast, German managers tended to use moral arguments when discussing corporate greening, often giving such arguments more weight than financial arguments. Overall, the study suggests that the ‘moral muteness’ of managers is a British phenomenon and quite distinct from the German approach. The article ends in a short exploration of how this understanding can help managers better manage people, organisations and change across cultures

A Model for the Analysis of Caries Occurrence in Primary Molar Tooth Surfaces

Recently methods of caries quantification in the primary dentition have moved away from summary ‘whole mouth’ measures at the individual level to methods based on generalised linear modelling (GLM) approaches or survival analysis approaches. However, GLM approaches based on logistic transformation fail to take into account the time-dependent process of tooth/surface survival to caries. There may also be practical difficulties associated with casting parametric survival-based approaches in a complex multilevel hierarchy and the selection of an optimal survival distribution, while non-parametric survival methods are not generally suitable for the assessment of supplementary information recorded on study participants. In the current investigation, a hybrid semi-parametric approach comprising elements of survival-based and GLM methodologies suitable for modelling of caries occurrence within fixed time periods is assessed, using an illustrative multilevel data set of caries occurrence in primary molars from a cohort study, with clustering of data assumed to occur at surface and tooth levels. Inferences of parameter significance were found to be consistent with previous parametric survival-based analyses of the same data set, with gender, socio-economic status, fluoridation status, tooth location, surface type and fluoridation status-surface type interaction significantly associated with caries occurrence. The appropriateness of the hierarchical structure facilitated by the hybrid approach was also confirmed. Hence the hybrid approach is proposed as a more appropriate alternative to primary caries modelling than non-parametric survival methods or other GLM-based models, and as a practical alternative to more rigorous survival-based methods unlikely to be fully accessible to most researchers