Wet Slip Resistance of Plastic Based Material Flooring (PBM Flooring)

Tile Council of North America Product Performance Testing Laboratory, under the direction of Dr. John Sanders of the Bishop Materials Laboratory at Clemson University, measured the wet Dynamic Coefficient of Friction (DCOF) of 22 plastic based material (PBM1) flooring products that manufacturers2 advertise or claim to be waterproof, water resistant, or depict being used in areas where flooring gets wet.3 The claims suggest that such PBM products can be used where exposed to water. However, product literature for only five products tested in this report cautioned the products can be potentially slippery when wet, and no measurements of wet DCOF are provided by the product manufacturers for any of the PBM flooring products studied.4 This research examines whether the tested products are suitable for wet use, or instead should carry a dry use-only caution. ANSI A326.3, American National Standard Test Method for Measuring Dynamic Coefficient of Friction of Hard Surface Materials, was used to measure the wet DCOF of each PBM product. The ANSI A326.3 test method was developed through a broad consensus of stakeholders across the flooring industry and is widely used in the ceramic tile, polished concrete, and stone industries.5 The ANSI A326.3 testing showed 16 out of the 22 product specimens tested in this report had an average wet DCOF value below 0.42. Per ANSI A326.3, those 16 specimens are not suitable for wet use,6 although each tested product was advertised as waterproof, water resistant, or was depicted being used in areas where flooring gets wet. In addition, two out of 22 product specimens’ DCOF measured below 0.42 when tested parallel to the plank length, but above 0.42 when tested perpendicular to the plank length. These two products exhibited a potentially dangerous level of directionality (See Section 3.6.3) with a significant change in DCOF occurring depending on the direction of measurement. Further, four other products exhibited directionality. In total, 20 of the 22 products tested for this report exhibited either a low level of wet DCOF for products that are advertised for wet applications (18 of 22) or directionality when wet (6 of 22)7, and should be considered for a dry use-only cautionary statement

Genetic alterations and cancer formation in a European flatfish at sites of different contamination burdens

Fish diseases are an indicator for marine ecosystem health since they provide a biological end-point of historical exposure to stressors. Liver cancer has been used to monitor the effects of exposure to anthropogenic pollution in flatfish for many years. The prevalence of liver cancer can exceed 20%. Despite the high prevalence and the opportunity of using flatfish to study environmentally induced cancer, the genetic and environmental factors driving tumor prevalence across sites are poorly understood. This study aims to define the link between genetic deterioration, liver disease progression, and anthropogenic contaminant exposures in the flatfish dab (Limanda limanda). We assessed genetic changes in a conserved cancer gene, Retinoblastoma (Rb), in association with histological diagnosis of normal, pretumor, and tumor pathologies in the livers of 165 fish from six sites in the North Sea and English Channel. The highest concentrations of metals (especially cadmium) and organic chemicals correlated with the presence of tumor pathology and with defined genetic profiles of the Rb gene, from these sites. Different Rb genetic profiles were found in liver tissue near each tumor phenotype, giving insight into the mechanistic molecular-level cause of the liver pathologies. Different Rb profiles were also found at sampling sites of differing contaminant burdens. Additionally, profiles indicated that histological “normal” fish from Dogger sampling locations possessed Rb profiles associated with pretumor disease. This study highlights an association between Rb and specific contaminants (especially cadmium) in the molecular etiology of dab liver tumorigenesis

BIOECONOMIC MODELING OF THE GULF SHRIMP FISHERY: AN APPLICATION TO GALVESTON BAY AND ADJACENT OFFSHORE AREAS

Resource /Energy Economics and Policy,

New Radiocarbon-Dated Vertebrate Fossils from Herschel Island: Implications for the Palaeoenvironments and Glacial Chronology of the Beaufort Sea Coastlands

Palaeontological research on Herschel Island, Yukon, has yielded a diverse collection of Quaternary marine and terrestrial vertebrate fossils. The terrestrial faunal remains, which have largely been collected as allochthonous beach debris at Pauline Cove, are dominated by Yukon horse (Equus sp.), with fewer specimens of steppe bison (Bison priscus), proboscideans (Mammuthus primigenius and a single Mammut americanum specimen), and other large and medium-sized mammals. This pattern of a horse-dominated Late Pleistocene fauna is consistent with those from the North Slope of Alaska and further demonstrates that conditions in northernmost Beringia were more arid than those in interior areas such as Fairbanks or the Klondike. This paper presents new AMS radiocarbon dates on terrestrial vertebrate fossils and peat from the island that span the range from greater than 53 000 to modern 14C yr BP. When considered with other data from the region, our new radiocarbon-dated fauna cannot adequately resolve whether the Herschel Island ice-thrust ridge was formed during the Early Wisconsinan or the Late Wisconsinan advance of the Laurentide Ice Sheet over the Yukon Coastal Plain.Des fouilles paléontologiques réalisées sur l’île Herschel, au Yukon, ont permis de prélever une collection variée de fossiles marins et de fossiles vertébrés terrestres du quaternaire. Les restes de faune terrestre, qui ont surtout été ramassés sous la forme de débris de plage allochtones à Pauline Cove, prennent la forme de restes de chevaux du Yukon en prédominance (Equus sp.), parsemés de quelques spécimens de bisons priscus (Bison priscus), de proboscidiens (Mammuthus primigenius et d’un seul spécimen de Mammut americanum), ainsi que d’autres mammifères de taille moyenne et de grande taille. La prédominance de faune du type cheval du Pléistocène tardif correspond à celle enregistrée sur le versant nord de l’Alaska et montre encore une fois que les conditions qui régnaient dans la partie la plus au nord de la Béringie étaient plus arides que les conditions qui prévalaient dans les régions de l’intérieur, comme à Fairbanks ou au Klondike. Dans ce document, nous présentons de nouvelles dates établies par le radiocarbone SMAquant aux fossiles de vertébrés terrestres et à la tourbe de l’île, dates allant de plus de 53 000 14C années BP à l’ère moderne. Lorsque ces données sont considérées à la lumière d’autres données de la région, la nouvelle faune datée par le radiocarbone ne nous permet pas de déterminer adéquatement si la dorsale découlant de la poussée des glaces de l’île Herschel a été formée pendant la progression du Wisconsinien précoce ou du Wisconsinien tardif de la nappe glaciaire laurentienne sur la plaine côtière du Yukon

TREX1 is expressed by microglia in normal human brain and increases in regions affected by ischemia

BACKGROUND: Mutations in the three-prime repair exonuclease 1 (TREX1) gene have been associated with neurological diseases, including Retinal Vasculopathy with Cerebral Leukoencephalopathy (RVCL). However, the endogenous expression of TREX1 in human brain has not been studied. METHODS: We produced a rabbit polyclonal antibody (pAb) to TREX1 to characterize TREX1 by Western blotting (WB) of cell lysates from normal controls and subjects carrying an RVCL frame-shift mutation. Dual staining was performed to determine cell types expressing TREX1 in human brain tissue. TREX1 distribution in human brain was further evaluated by immunohistochemical analyses of formalin-fixed, paraffin-embedded samples from normal controls and patients with RVCL and ischemic stroke. RESULTS: After validating the specificity of our anti-TREX1 rabbit pAb, WB analysis was utilized to detect the endogenous wild-type and frame-shift mutant of TREX1 in cell lysates. Dual staining in human brain tissues from patients with RVCL and normal controls localized TREX1 to a subset of microglia and macrophages. Quantification of immunohistochemical staining of the cerebral cortex revealed that TREX1 CONCLUSIONS: TREX1 is expressed by a subset of microglia in normal human brain, often in close proximity to the microvasculature, and increases in the setting of ischemic lesions. These findings suggest a role for TREX