This opportunistic study focussed on the quantification of microplastics in the River Thames water column, the catchment responsible for draining Greater London. Two sites on the tidal Thames were ...sampled; one upstream of the City of London at Putney, and the other downstream at Greenwich. Water column samples were collected from June through to October 2017, being taken on the ebb and flood tides, at the surface and a depth of 2 m. Microplastics (excluding microfibres) were identified to test whether the load varied between the two sites in relation to tide, depth and season. Secondary microplastics, films and fragments, contributed 93.5% of all those found at Putney and Greenwich. Site, tide, depth and month affected density, with the combined interaction of month and site found to have the greatest influence on microplastics. Fourier Transform Infrared Spectroscopy analysis showed that polyethylene and polypropylene were the most common polymers collected from the River, suggesting broken down packaging was the primary source of microplastics in these samples. Excluding microfibres, the estimate of microplastics in the water column was 24.8 per m3 at Putney and 14.2 per m3 at Greenwich. These levels are comparable to some of the highest recorded in the world.
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•Water column microplastics were 24.8 per m3 at Putney and 14.2 per m3 at Greenwich.•Secondary microplastics, films and fragments, contributed 94% of all microplastics.•Combined month/site interaction had greatest influence on microplastic abundance.•Polyethylene and polypropylene were the most common polymers in samples.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Abstract The primary freshwater crab mandibular palp is described as possessing two or three divisions (joints) and its terminal article as being either unbranched (simple) or bilobed. Currently, ...this provides two important familial characters. Addressed here are the long-standing differences in the number of mandibular palp articles between some freshwater crabs and other brachyurans by adopting a standardized terminology based on a generalized brachyuran limb using homology-based terms that allow comparisons with all brachyurans. As a result, the freshwater crab mandible is redescribed as a four-part appendage comprising the coxa (biting jaw) and basis, from which originates a two-articled inner ramus (endopod). A detailed examination of the joint between the basis and the first endopod article of the palp indicates that its expression varies from distinct to obscure, but it is nevertheless present in all freshwater and marine crab families examined here, including those species currently described as possessing a two-articled palp. The coxa, basis, and first endopod articles of the mandibular palp are all uniform and generally not diagnostic within the Brachyura. The terminal endopod article of freshwater crabs, however, is morphologically diverse and provides a familial diagnostic character. The wider implications of these findings for the Brachyura are discussed.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Fuel cells are energy conversion devices that show great potential in numerous applications ranging from automobiles to portable electronics. However, further development of fuel cell components is ...necessary for them to become commercially viable. One component critical to their performance is the polymer electrolyte membrane, which is an ion conductive medium separating the two electrodes. While proton conducting membranes are well established (e.g., Nafion), hydroxide conducting membranes (alkaline anion exchange membranes, AAEMs) have been relatively unexplored by comparison. Operating under alkaline conditions offers significant efficiency benefits, especially for the oxygen reduction reaction; therefore, effective AAEMs could significantly advance fuel cell technologies. Here we demonstrate the use of ring-opening metathesis polymerization to generate new cross-linked membrane materials exhibiting high hydroxide ion conductivity and good mechanical properties. Cross-linking allows for increased ion incorporation, which, in turn supports high conductivities. This facile synthetic approach enables the preparation of cross-linked materials with the potential to meet the demands of hydrogen-powered fuel cells as well as direct methanol fuel cells.
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IJS, KILJ, NUK, PNG, UL, UM
•Sub-surface rubbish items intercepted in fyke-nets in the River Thames.•The trapping of 8490, mainly plastic, items during a three month period.•Over 20% of rubbish items were components of sanitary ...products.•Most contaminated sites were in the vicinity of sewage treatment works.•Evidence for significant sub-surface transport of rubbish in the Thames Estuary.
Although contamination of the marine ecosystems by plastics is becoming recognised as a serious pollution problem, there are few studies that demonstrate the contribution made by freshwater catchments. Over a three month period from September to December 2012, at seven localities in the upper Thames estuary, 8490 submerged plastic items were intercepted in eel fyke nets anchored to the river bed. Whilst there were significant differences in the numbers of items at these locations, the majority were some type of plastic. Additionally in excess of 20% of the litter items were components of sanitary products. The most contaminated sites were in the vicinity of sewage treatment works. While floating litter is visible, this study also demonstrates that a large unseen volume of submerged plastic is flowing into the marine environment. It is therefore important that this sub-surface component is considered when assessing plastic pollution input into the sea.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
This study presents evidence for microplastic contamination in two resident species of brachyuran crab from the Thames Estuary: the native shore crab, Carcinus maenas (Linneaus, 1758) and the ...invasive Chinese mitten crab, Eriocheir sinensis (H. Milne Edwards, 1853). The gills, gastric mill and intestine of 94 C. maenas and 41 E. sinensis were examined. Crabs were sampled periodically (ca. every three months) between December 2018 and October 2019. A total of 874 plastics were recovered, ranging 34 μm–34 mm in length. Overall, 71.3% and 100% of C. maenas and E. sinensis, respectively, contained at least one item (fibre, film, fragment or tangle of fibres) in the gill chamber, gastric mill or gastrointestinal tract. The most common items were fibres (78.5%) but in some cases, particularly in the gastric mill, these were aggregated into tangles (7.8%). Almost all E. sinensis contained tangles of fibres (95.1%), whereas, relatively few C. maenas contained similar tangles (10.6%).
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•Thames Estuary crabs, Carcinus maenas and Eriocheir sinensis, ingest microplastic.•Fibres were the most dominant form recovered (detection limit was 32 μm in length).•Tangles of fibres, many comprising >100 items, had accumulated in the gastric mill.•Tangles were too large to pass beyond the gastric mill and may be retained.•Balloon, sanitary pad, carrier bag and elastic band fragments were also ingested.
This study presents a comparison of microplastic load in two species of brachyuran crab in the Thames Estuary, over 70% of sampled individuals were contaminated.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Macroplastic is a growing concern for marine environments with estuaries providing a major pathway for pollution from land-based sources to the sea. In the Thames Estuary, plastic was abundant ...floating below the surface and on the riverbed, with an average catch per unit effort of 0.57 ± 0.42 and 2.75 ± 2.44 item per minute respectively. Whilst the abundance of litter differed between midwater and benthic zones, the types of products recovered did not. These were identified through visual examination and use of a unique citizen science engagement protocol, allowing for the item age, brand and countries of origin to be established. The majority of litter from the present study (n = 1335) was packaging (40%), some of which was over 30-years old and may have originated from landfill run off. Also abundant was sewage-related debris, the inputs of which was related to heavy or prolonged rainfall. Peaks in this material were recorded in September 2020 following the greatest volume of rain recorded in a single day and in June 2019 after the longest period of continuous rainfall. The Covid-19 pandemic did not influence the abundance or diversity of plastic recovered between December 2018 and September 2020. The durability of plastic ensures it has high potential for harm through entanglement, deoxygenation of sediment and ingestion. The retention in the environment also increases opportunities to fragment into micro- or nanoplastics and, therefore, it is important to monitor plastics at both a macro- and micro-scale.
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•Macrolitter is abundant in the water column and on the riverbed.•Litter is 5 × more likely to be recovered on the riverbed than the water column.•Single-use plastic, including food packaging is most common.•Some of the recovered items are ca. 30 years old.•Sewage outfalls and runoff from landfill are major sources of macrolitter.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The citation of Charles Spence Bate has become a source of uncertainly in the literature. Indeed, for some taxa his authority is given as "Spence Bate", whilst others "Bate" e.g. Artemesia longinaris ...Spence Bate, 1888 compared with Ibacus brevipes Bate, 1888. In order to resolve this inconsistency, a lengthy manual search of selected contemporary journals for the period from ca. 1854 to 1889 was undertaken with special reference to the name Charles Spence Bate being listed alphabetically by family/surname either under "Bate", "Spence Bate" or "Spence-Bate". Overwhelming evidence indicated that his family/surname is Bate. Furthermore, as there are a number of carcinologists also with the family name Bate, therefore it is recommended that taxa described by Charles Spence Bate should be referred to as C.S. Bate, for example Artemesia longinaris C.S. Bate, 1888 and Ibacus brevipes C.S. Bate, 1888.
OBJECTIVE:To estimate the accuracy of endometrial thickness measurement in the detection of endometrial cancer among women with postmenopausal bleeding with individual patient data using different ...meta-analytic strategies.
DATA SOURCES:Original data sets of studies detected after reviewing the included studies of three previous reviews on this subject. An additional literature search of published articles using MEDLINE databases was preformed from January 2000 to December 2006 to identify articles reporting on endometrial carcinoma and sonographic endometrial thickness measurement in women with postmenopausal bleeding.
METHODS OF STUDY SELECTION:We identified 90 studies reporting on endometrial thickness measurements and endometrial carcinoma in women with postmenopausal bleeding.
TABULATION, INTEGRATION, AND RESULTS:We contacted 79 primary investigators to obtain the individual patient data of their reported studies, of which 13 could provide data. Data on 2,896 patients, of which 259 had carcinoma, were included. Several approaches were used in the analyses of the acquired data. First, we performed receiver operator characteristics (ROC) analysis per study, resulting in a summary area under the ROC curve (AUC) calculated as a weighted mean of AUCs from original studies. Second, individual patient data were pooled and analyzed with ROC analyses irrespective of study with standardization of distributional differences across studies using multiples of the median and by random effects logistic regression. Finally, we also used a two-stage procedure, calculating sensitivities and specificities for each study and using the bivariate random effects model to estimate summary estimates for diagnostic accuracy. This resulted in rather comparable ROC curves with AUCs varying between 0.82 and 0.84 and summary estimates for sensitivity and specificity located along these curves. These curves indicated a lower AUC than previously reported meta-analyses using conventional techniques.
CONCLUSION:Previous meta-analyses on endometrial thickness measurement probably have overestimated its diagnostic accuracy in the detection of endometrial carcinoma. We advise the use of cutoff level of 3 mm for exclusion of endometrial carcinoma in women with postmenopausal bleeding.
More than any other labor victory of the 1930s, the emergence of the Steel Workers' Organizing Committee symbolized the rise of organized labor to a position of power in the United States. Yet, as ...the contributors to this volume demonstrate, the unionization of the steel industry, and most notably the role of SWOC and Philip Murray in that process, has received far less attention than it deserves. Beginning with a discussion of why the unionization of steel has been relatively neglected by labor historians, the contributors to this volume analyze early organizing efforts in steel, the major transformations wrought and felt by the union, and the character of the union members and leaders. Critical throughout is discussion of the role of Philip Murray in shaping the United Steelworkers of America into one of the premier economic, social, and political institution of the war years and beyond. Contributors: David Brody, Malvyn Dubovsky, Ronald L. Filippelli, Mark McColloch, Ronald W. Schatz
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