92 research outputs found
Baseline environmental radon survey at Lake Way, Western Australia, September 1979.
A survey of radon and radon daughters in the air has been made at and within a few kilometres of the possible uranium mine near Millbillillie at the northern edge of Lake Way, Western Australia. The data have been correlated with meteorological measurements taken concurrently with the radon survey. In addition radon emanation rates and radon levels in water have been measured at a broad range of sites to define more closely the magnitude and extent of radon in the environment
222Rn calibrated mercury fluxes from terrestrial surfaces of southern Africa derived from observations at Cape Point, South Africa
Gaseous elemental mercury (GEM) and 222Rn, a radioactive gas of primarily terrestrial origin with a half-life of 3.8 days, have been measured simultaneously at Cape Point, South Africa, since March 2007. Between March 2007 and December 2009 altogether 59 events with high 222Rn concentrations were
identified. GEM correlated with 222Rn in 41 of the events and was constant during the remaining events without significant correlation. The average GEM/222Rn emission ratio of all events was -0.0047 ± 0.0054 pg
mBq-1, with ± 0.0054 being the standard error of the average. With an emission rate of 1.1 222Rn atoms cm-2 s-1 and a correction for the transport duration, this emission ratio corresponds to a radon calibrated flux of about -0.53 ± 0.62 ng m-2 h-1 which is statistically not distinguishable from zero. With wet deposition, which is not included in this estimate, the terrestrial surface of southern Africa appears to be a net mercury sink. © Owned by the authors, published by EDP Sciences, 201
222Rn-calibrated mercury fluxes from terrestrial surface of southern Africa
Gaseous elemental mercury (GEM) and 222Rn, a radioactive gas of primarily terrestrial origin with a half-life of 3.8 days, have been measured simultaneously at Cape Point, South Africa, since March 2007. Between March 2007 and December 2011, altogether 191 events with high 222Rn concentrations were identified. GEM correlated with 222Rn in 94 of the events and was constant during almost all the remaining events without significant correlation. The average GEM / 222Rn flux ratio of all events including the non-significant ones was −0.0001 with a standard error of ±0.0030 pg mBq−1. Weighted with the event duration, the average GEM / 222Rn flux ratio was −0.0048 ± 0.0011 pg mBq−1. With an emission rate of 1.1 222Rn atoms cm−2 s−1 and a correction for the transport time, this flux ratio corresponds to a radon-calibrated flux of about −0.54 ng GEM m−2 h−1 with a standard error of ±0.13 ng GEM m−2 h−1 (n = 191). With wet deposition, which is not included in this estimate, the terrestrial surface of southern Africa seems to be a net mercury sink of about −1.55 ng m−2 h−1. The additional contribution of an unknown but presumably significant deposition of reactive gaseous mercury would further increase this sink.© 2013, European Geosciences Unio
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Overcoming Barriers to Cross-cultural Cooperation in AI Ethics and Governance
Abstract: Achieving the global benefits of artificial intelligence (AI) will require international cooperation on many areas of governance and ethical standards, while allowing for diverse cultural perspectives and priorities. There are many barriers to achieving this at present, including mistrust between cultures, and more practical challenges of coordinating across different locations. This paper focuses particularly on barriers to cooperation between Europe and North America on the one hand and East Asia on the other, as regions which currently have an outsized impact on the development of AI ethics and governance. We suggest that there is reason to be optimistic about achieving greater cross-cultural cooperation on AI ethics and governance. We argue that misunderstandings between cultures and regions play a more important role in undermining cross-cultural trust, relative to fundamental disagreements, than is often supposed. Even where fundamental differences exist, these may not necessarily prevent productive cross-cultural cooperation, for two reasons: (1) cooperation does not require achieving agreement on principles and standards for all areas of AI; and (2) it is sometimes possible to reach agreement on practical issues despite disagreement on more abstract values or principles. We believe that academia has a key role to play in promoting cross-cultural cooperation on AI ethics and governance, by building greater mutual understanding, and clarifying where different forms of agreement will be both necessary and possible. We make a number of recommendations for practical steps and initiatives, including translation and multilingual publication of key documents, researcher exchange programmes, and development of research agendas on cross-cultural topics
What's wrong with the murals at the Mogao Grottoes : a near-infrared hyperspectral imaging method
Although a significant amount of work has been performed to preserve the ancient murals in the Mogao Grottoes by Dunhuang Cultural Research, non-contact methods need to be developed to effectively evaluate the degree of flaking of the murals. In this study, we propose to evaluate the flaking by automatically analyzing hyperspectral images that were scanned at the site. Murals with various degrees of flaking were scanned in the 126th cave using a near-infrared (NIR) hyperspectral camera with a spectral range of approximately 900 to 1700 nm. The regions of interest (ROIs) of the murals were manually labeled and grouped into four levels: normal, slight, moderate, and severe. The average spectral data from each ROI and its group label were used to train our classification model. To predict the degree of flaking, we adopted four algorithms: deep belief networks (DBNs), partial least squares regression (PLSR), principal component analysis with a support vector machine (PCA + SVM) and principal component analysis with an artificial neural network (PCA + ANN). The experimental results show the effectiveness of our method. In particular, better results are obtained using DBNs when the training data contain a significant amount of striping noise
Investigating porcine parvoviruses genogroup 2 infection using in situ polymerase chain reaction
Abstract Background Porcine parvovirus 2 (PPV2) was detected in swine serum without showing any relationship with disease. The emergence of the virus seemed to be a unique event until other genetically highly similar parvoviruses were identified in China and, later in 2012, the presence of the virus was also described in Europe. PPV2 is widely distributed in pig populations where it is suspected to be involved in respiratory conditions, based on its frequent detection in lung samples. In order to investigate the potential pathogenic involvement of PPV2, 60 dead pigs were examined from two farms. They were necropsied and tested for PPV2 and PCV2 (Porcine circovirus type 2) by PCR; by Brown and Brenn (B&B) staining for bacteria; by immunohistochemistry (IHC) to detect CD3, Swine leukocyte antigen class II DQ (SLAIIDQ), lysozyme, porcine reproductive and respiratory syndrome virus (PRRSV), swine influenza (SIV), Mycoplasma hyopneumoniae (Mhyo); and by in situ hybridization (ISH) to detect ssDNA and dsDNA of PCV2. PPV2 positive samples were subjected to in situ polymerase chain reaction (IS-PCR) including double staining method to detect PPV2 and host cell markers. To calculate statistical difference we used GENMOD or LOGISTIC procedures in Statistical Analysis System (SAS®). Results We found that the PPV2 was localized mostly in lymphocytes in lungs, lymph nodes and liver. Neither CD3 antigen nor lysozyme was expressed by these infected cells. In contrast, low levels of SLAIIDQ were expressed by infected cells, suggesting that PPV2 may have a specific tropism for immature B lymphocytes and/or NK lymphocytes though possibly not T lymphocytes. Conclusion The overall conclusion of this study indicates that PPV2 may contribute to the pathogenesis of pneumonia
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