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Bottom trawling grounds have been expanding to deeper areas of the oceans since the mid‐XXth century, and mitigating strategies aimed to protect fish stocks, such as temporal trawling closures, have recently been implemented. Here we investigated the biogeochemical properties of sediment from a deep‐sea trawling ground in Palamós Canyon (NW Mediterranean) to assess the effects of a 2‐months trawling closure in the recovery of sedimentary organic matter. In comparison to untrawled areas, the continuous erosion and sediment mixing in trawling grounds led to coarser reworked sediments impoverished in organic carbon (∼30% loss) and promoted the degradation of labile compounds (52–70% loss). These impacts persisted after the temporal trawling closure, highlighting that this management strategy is insufficient to restore the seafloor. Considering the continuous expansion of bottom trawling grounds, this activity could have significant and irreversible biogeochemical impacts on ocean margins at a global scale, hampering their carbon burial capacity. Plain Language Summary: Bottom trawling grounds have been expanding to deeper areas of the oceans since the mid‐XXth century, causing substantial effects to fish populations. In order to reduce this impact, new management strategies have been introduced, such as establishing temporal trawling closures to allow fish populations to recover. Bottom trawling not only poses a threat to fish populations but also to the seafloor, since the continuous contact of trawling gear on the bottom erodes large volumes of sediment and reduces the amount and quality of organic matter. In this study, we assessed the effect of a 2‐months trawling closure in deep‐sea bottom trawling grounds in Palamós Canyon (NW Mediterranean) by collecting sediment samples in trawled and untrawled areas during different seasons. Our results show that sediment samples in the trawled site had substantially lower organic matter contents than in the untrawled site, and the remaining organic matter had poor nutritional quality. These impacts persisted after the temporal trawling closure, highlighting that this management strategy is insufficient to restore the seafloor. Considering the continuous expansion of bottom trawling grounds, this activity could have significant and irreversible impacts in organic matter available for benthic species in ocean margins at a global scale. Key Points: Bottom trawling disturbance on the deep seafloor depletes organic matter through erosion and degradation, hampering its preservationA 2‐month seasonal trawling closure is insufficient to restore the seafloor and it is estimated that it would take decades to recoverBottom trawling causes organic carbon losses from the seafloor comparable to those generated on land by tillage of agricultural fields [ABSTRACT FROM AUTHOR]

In this study, an individual (NG) with the semantic varient of primary progressive aphasis (svPPA) was assessed with tasks designed to investigate the recognition and activation of semantic knowledge about unique entities. NG had significant difficulties in the recognition of brand names and famous names but was largely unimpaired in the recognition of logos and famous faces. However, she was impaired in tasks requiring the activation of semantic representations of logos, brand names, famous faces, and famous names. These results suggest that the recognition of unique entities results from the interaction of perceptual and conceptual processes and, that the ability to activate semantic information about these entities can be affected in svPPA. [ABSTRACT FROM AUTHOR]

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Handheld (portable) X-ray fluorescence (pXRF) instruments are designed for use in the exploration for base metals, precious metals, and specialty metals (e.g. rare earth elements (REE), Ta, and Nb) and allow rapid decision-making directly in the field. This paper evaluates the technical merits and limitations of pXRF technology in the exploration for specialty metals using data generated from the analysis of three geochemical standards and a silica blank: Standard Reference Material NIST 2780 from the National Institute of Standards and Technology, Gaithersburg; the Certified Reference Material 'TRLK' Rare Earth Ore 'CGL 124' from the Mongolia Central Geological Laboratory; the Reference Niobium Ore OKA-1 (CANMET); and a silica blank described as Si (IV) oxide (99.8 % on metal basis) from Alpha Aesar (Ward Hill, MA, USA). The data was acquired over a period of nearly 2 years as a by-product of several distinct specialty metal-related projects using the same pXRF instrument and the same settings. Instrumental analytical accuracy was determined using the percent difference (%diff) between the average concentrations of the pXRF instrument readings and the reported certified values of the standard. Percent relative standard deviation (%RSD) was used as a measure of precision. Smaller %diff and %RSD indicate more accurate and precise data, and the accuracy and precision of the pXRF depended strongly on the elemental concentrations in the standards used. Box and whisker diagrams were used to illustrate characteristics of pXRF data sets (mean, lower and upper quartiles, and range) corresponding to individual standards. The bias of the pXRF determinations (under/overestimation) relative to certified values of individual standards are also depicted on these diagrams. This study indicates that the pXRF was capable of producing readings for Si, K, Al, Fe, Ca, Ti, Pb, Zn, Sr, Ag, Cd, Th, Sb, P, S, Mo, Mn, Mg, As, Nb, Rb, La, Ce, Pr, Nd, and Y within 10 %RSD of the reported certified value in at least one of the three standards measured, depending on the concentrations within that standard. The instrument was able to provide relatively accurate and precise data for Nd, Pr, Ce, La, and Y (%diff, ≤17; %RSD, ≤3.7) when the concentrations were greater than 1,000 ppm (e.g., rare earth ore CGL 124). It generated lower quality data (in terms of %diff and %RSD) when concentrations of these elements were in the hundreds parts per million range or lower (NIST 2780). As for Nb, the best %RSD (2.2) was obtained on the Nb Ore OKA-1 with an accompanying %diff of 34. This indicates that the instrument is suitable for use in the exploration and development of carbonatite-related REE deposits such as: Mountain Pass (California), Bayan Obo (Inner Mongolia), Wicheeda Lake (British Columbia), St Honoré, Oka, and Eldor (Quebec). By extension, the instrument is also suitable for the exploration of apatite-monazite veins (Steenkampskraal) and peralkaline intrusion-related deposits such as Kipawa, Nechalacho (Northwest Territories), or Strange Lake (Quebec; Labrador, Newfoundland). A pXRF without a radioactive source cannot be used to analyze for most of the heavy lanthanides; however, Y can be used as a pathfinder for these elements. Limited but effective use of the pXRF in exploration for ion adsorption clay deposits with grades as low as 500 ppm total REE appears possible. The pXRF could also be used in the exploration for carbonatite-related Nb-bearing deposits such as St Honoré (Quebec) and Aley (British Columbia), or in the exploration for lower-grade Nb-Ta deposits such as Upper Fir (British Columbia), justifying the need for future case studies. [ABSTRACT FROM AUTHOR]

The authors have successfully fabricated stationary micro-optical shutter arrays based on the well-known transmitting semiconductor (on) to the reflecting metallic (off) phase transition of thermochromic W-doped VO2 active layers operating at room temperature and driven by an external voltage. This shutter consists of 16 active planar micro-optical slits for which the optical switching (either transmittance or reflectance) can be controlled individually. This allows performing any desirable on-off switching combinations. The current-voltage characteristic of the micro-slit shows that the current jumps when the phase transition occurs. Transmittance switching as high as 25 dB and reflectance switching of about 6 dB were achieved with this device at λ=1.55 μm. Therefore, this electrically controllable VO2-array can be used as a stationary Hadamard shutter to increase the sensitivity of infrared spectrometers. [ABSTRACT FROM AUTHOR]

Binding of pig hemoglobin (Hb) to Actinobacillus pleuropneumoniae lipopolysaccharide (LPS), either extracted or present at the surface of whole cells, was studied. After a short incubation period, pig Hb seemed to cover the bacterial cell surface and enhanced the cells' contrast when examined by transmission electron microscopy (TEM). Energy-dispersive X-ray spectroscopy analysis showed that the amount of elemental iron detected was increased when cells of A. pleuropneumoniae were incubated with pig Hb. Coating with pig Hb, however, did not interfere with the accessibility of O- and capsular antigens to antibodies on the bacterial cell surface. Binding of pig Hb and polymyxin B to lipid A of A. pleuropneumoniae was confirmed with a fluorescent probe (dansylcadaverine) displacement assay. The binding of pig Hb to extracted LPS resulted in a disaggregation of LPS as observed by TEM after negative staining. Additional evidence for a direct physical interaction between pig Hb and A. pleuropneumoniae LPS was demonstrated by a shift in the sedimentation velocity of LPS-Hb complexes determined by sucrose gradient centrifugation. Pig Hb binding to extracted LPS or to bacterial cells resulted in a significant decrease of chromogenic Limulus amebocyte lysate activation. Finally, the capacity of extracted LPS to induce NO2- in the presence of pig Hb was tested by using cell line J774 and determined by the Greiss' reaction. LPS alone induced, as expected, NO2- production, whereas the presence of pig Hb significantly reduced NO2- production by murine macrophages. Taken together, our results indicate that binding of pig Hb affected some physical and biological properties of A. pleuropneumoniae LPS. [ABSTRACT FROM PUBLISHER]

A new cell line, designated SPC G1 13, derived from dorsal vessels of larvae of Gromphadorhina laevigata has been established. The medium used is D. 73. The cells are fibroblastlike cells. Some of them are fixed; others, spindle-shaped or round, are in suspension. Most of the cells have the diploid chromosome number. The SPC G1 13 cell line is permissive to the chlamydia Rickettsiella grylli [ABSTRACT FROM AUTHOR]

The relationship between the consumption of fish containing methylmercury (MeHg) and human MeHg levels has been studied for many years. Although this relationship has been demonstrated and some models have been developed to assess the risks associated with fish consumption, there is still a need for a simple and efficient predicting toot thatcan be applied to community settings. This paper provides such a practical model developed through empirical evidence using two sources of data. In ideal conditions, models used to identify hazardous behaviour in individuals would be derived from theoretical and clinical models, however, these conditions are often technically difficult to meet. To overcome this problem, a more empirically oriented model has been developed, based on the estimation of personal mercury intake and its comparison to the Tolerable Daily Intake. The theory and methodology of the model development, including technical limitations, are presented first. The methodology is then applied to the real data to create the final model and the results given. Finally, a discussion of the model's accuracy, limitations and usefulness as a community health assessment tool is presented. [ABSTRACT FROM AUTHOR]

Health Canada has been collecting data on Inuit and First Nations' methylmercury (MeHg) levels for 25 years. A national overview has beencompleted and more focussed analyses have now been initiated. This paper deals with two interdependent analytical components: 1) a longitudinal overview of the two most extensively sampled communities in Canada: Grassy Narrows and Whitedog, the residents of which were exposed to 'point source' mercury pollution in the 1970's; 2) fetal and post-natal exposure to mercury in these two communities including an outline of the First Nation MeHg child development pilot project in the two communities. A retrospective analysis of Grassy Narrows and Whitedog shows a decreasing MeHg trend in both communities. In Grassy Narrows the average individual annual peak methylmercury level in blood has decreased significantly, from 23.80 ppb (range 1.50-- 322.90) in 1976 to 7.5 ppb (1.7--46.7) in 1995 (r= -0.65, p<0.001). In Whitedog the average peak has also decreased significantly, from 12.87 ppb (1.50--172.00) in 1976 to 6.1 ppb (1.7--33.3) in 1995 (r= -0.59, P<0.005). However, behind these positive trends is the reality of two communities still suffering the effects of disrupted lifestyles and socio-cultural damage. A number of cord blood samples, maternal blood samples, and samples from women of child-bearing age from these communities have been in the 'risk' group (according to the 1990 WHO guidelines).We are therefore now assessing the long term effects of fetal exposure in the communities. Standard clinical examinations in the past failed to prove abnormalities attributable to methylmercury but did not include subtle neuropsychological development tests. Many of the fetally exposed children are now in secondary school. Therefore, we have initiated a pilot project to assess long term effects of methylmercury exposure on the neuropsychological development of these children whose fetal exposure we know. The pilot child development project whichwa [ABSTRACT FROM AUTHOR]