A New Phase Speciation Leaching Procedure for the Determination of Metals in Oxic and Anoxic Sediments

Toxic trace elements such as cadmium, lead, chromium, and arsenic released by human activities can accumulate in marine and estuarine sediments, where these metals are often sequestered until local environmental changes (e.g., redox, salinity, and/or pH) allow these elements to be reintroduced into the food web. In order to assess the extent of toxic trace element contamination in sediment, numerous leaching schemes have been developed that separate sediment-bound trace metals into operationally defined geochemical phases. These phase speciation leaching schemes are typically designed with the purpose of being used on either oxic or anoxic sediments. However, natural sediments often contain prominent redox boundaries; therefore, it is useful to develop a single phase speciation leaching scheme which can be used on both oxic and anoxic sediments. A six step leaching scheme was developed in order to separate sediment-bound trace elements into five operationally defined phases: exchangeable, oxide, acid volatile sulfide (AVS), organic, and pyrite. The efficacy of five of the six leaching steps (oxide, AVS, organic #1 and #2, and pyrite) was evaluated using standard reference sediments (NIST 2702 and BCR-701) and actual sediment samples. Overall, the results show that the six step leaching process compared well with other frequently utilized phase speciation leaching schemes ( Tessier and optimized BCR ). With the exception of some surface sediment oxides carrying over into the AVS phase, the leach AVS and pyrite results compared well with H2S generation sediment sulfide analysis methods. The organic phase extractions were about three times more effective (∼60% removal efficiency) at removing labile organic material (e.g., proteins and humic and fulvic acids) in sediment than refractory organics (e.g., protokerogens) (∼20% removal efficiency). The six step leach method was applied to bulk sediments obtained from three estuaries with differing geochemical environments (salinity and sediment C and S concentrations). The sediment phase speciation results for the major (Fe, Mn, and Ca) and trace metals (Cd, Pb, Cr, and As) of interest are similar to those reported by other workers for similar environments, with the majority of the trace metals being located in the oxide and organic phases

Consumer Preferences for Cluster Raisins: A Focus Group Investigation

The U.S. raisin industry has experienced a decline in acreage and in number of growers in recent years. One firm is trying a novel approach to marketing raisins, namely, by marketing them still attached to the vine. This product is called cluster raisins. In order to explore consumer preferences related to cluster raisins, and to generate new product ideas and preferred marketing methods, two focus group interviews were implemented. Findings included that a young (i.e., 18 - 25 years) market segment would be a recommended target market. Also included are recommendations regarding price, packaging, and methods of increasing consumer awareness. Recommended marketing channels include specialty markets (e.g., Trader Joe's or Whole Foods) and gift baskets.Marketing,

Vacuum energy in a spherically symmetric background field

The vacuum energy of a scalar field in a spherically symmetric background field is considered. It is expressed through the Jost function of the corresponding scattering problem. The renormalization is discussed in detail and performed using the uniform asymptotic expansion of the Jost function. The method is demonstrated in a simple explicit example.Comment: 14 pages, 1 Postscript figur

Savannah Hockey Classic Attendance Motivation

The Savannah Hockey Classic has become a very successful annual university club hockey team tournament. The 21st edition of the tournament was held in January 2020 in Savannah, Ga. featuring the Georgia Institute of Technology, University of Florida, Florida State University, and University of Georgia club hockey teams—the same teams that have comprised the tournament for many years. This study utilized Personal Investment Theory (Braskamp, 1986) and the SPEED scale (Funk, Filo, Beaton, & Pritchard, 2009) for attendance motivation assessment. Social interaction motivations were significantly higher for county residents, spectators attending with friends, spectators attending with family, and past Savannah Hockey Classic attendees. Motivations related to athlete performance were significantly higher for those who had attended the event in the past. Excitement based motivations were greater for those who had attended the event in the past as well as for those who identified as a fan of one of the teams. There were significant differences related to the esteem and diversion constructs for those who had a team rooting interest. The article fills a gap in the literature by providing the first study of club hockey attendance motivations

Cognitive improvement in children with CKD after transplant

Icard P, Hooper SR, Gipson DS, Ferris ME. Cognitive improvement in children with CKD after transplant. Pediatr Transplantation 2010: 14:887–890. © 2010 John Wiley & Sons A/S.The primary purpose of this paper was to examine the cognitive functioning of children with CKD receiving transplantation to children with CKD not receiving transplantation, and a healthy control group. The sample included six children with CKD receiving transplant, 28 children with CKD being treated conservatively, and 23 healthy controls. All participants were administered intellectual (IQ) or developmental assessments at baseline and at a one-yr follow-up. Results revealed that children with CKD who had received transplant showed a significant increase in their intellectual/developmental functioning post transplant compared to children with CKD not receiving transplant. Although their overall intellectual/developmental level was not fully normalized, when compared with the healthy control group, the change scores for the transplant group reflected over a 12 point increase, moving the group from the borderline range to the low average range of functioning. In this regard, pediatric transplantation appears to have a positive impact on the intellectual and developmental functioning of children with CKD.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/79239/1/j.1399-3046.2010.01359.x.pd

The nervous system and chronic kidney disease in children

This paper provides a review of the literature on the nervous system involvement incurred by children and adolescents with chronic kidney disease (CKD), with a particular focus on neuropsychological functioning. In addition to an historical overview of earlier literature, published studies from the past 14 years that address both central and peripheral nervous system function in children with CKD are reviewed (1990–2003). These studies span work in neuroimaging, electrophysiology, and neuropsychology. A key focus for this review is on variables that might affect neurodevelopmental status in these children. The paper concludes with suggestions for achieving progress in the understanding of this complication of kidney disease in children

Print & (Pedagogical Issues in Printmaking)

This panel addresses how the contemporary printmaker must adapt traditional approaches to making, collaborating, teaching, and networking to an increasingly digital landscape. With creative adaptation a necessity for artists and the medium of printmaking\u27s sustained relevance, panelists will discuss their experiences: transforming traditional journals into digital archives, seeking innovative approaches to portfolio exchanges, pursuing alternative vocations, and readying the next generation of artists for these challenges

Cougars in Kansas

The presence of the cougar (Puma concolor) in the state of Kansas is a controversial issue. Since 1999, 234 cougar sightings have been reported to the Extension Wildlife Specialist at Kansas State University. To those who have reported such sightings, the existence of cougars in Kansas is undeniable. Others, however, question the validity of such sightings as providing evidence of cougars. After surveying other governmental agencies and organizations, we discovered that acceptable identification criteria for rare or unusual felines included things beside sightings: voucher specimens, DNA from hair or scat, tracks, prey carcasses, and photographs or videos. The cougar sightings from Kansas were plotted on a map using ArcGIS 9.1, and the Spatial Analyst Tool was used to test the 3 hypotheses of: 1) cougar sightings are located near rivers, as cover is provided; 2) sightings of cougars are located around captive felines that may be potential breeding partners; and 3) cougar sightings are located within the vicinity of cities with populations greater than or equal to 35,000 people, as the higher densities of observers may be associated with more opportunities for sightings. Our data led us to accept all 3 hypotheses