Carbon Removal of Organohalides in Drinking Water

Drinking water samples provided by Orlando Utilities from various locations and from Florida Technological University were analyzed for organohalides. Compounds tentatively identified were 0.0024 mg/l DDT, 0.003 mg/l phosdrin, 0.00036 mg/l BHC, and 0.000095 mg/l endosulfan. These concentrations are well below recommended limits for drinking water. Two water samples were mixed with 10 mg/l of 20-40 mesh granular activated carbon, agitated for 2 minutes and then allowed to settle in the flask for 45 minutes. A reduction in the organohalide concentration varied from 25 to 98 percent of the original concentration. Also, a solution of seven common pesticides of 0.1 mg/l each were mixed with 1, 5, 10, 25, and 50 mg/l of carbon. The results indicate a reduction of 99 percent or better for all pesticides with 5 ppm carbon concentration

Creating Digital Content for the Individual Learner: A Personalized Approach to Online Learning

Online learning programs are becoming more and more popular; however, they are challenged with creating digital content catered to individual students’ needs and interests (Ziphorah, 2014). The concept of personalized learning is not new but advancements in educational technology have increased the potential for online learning programs to implement personalized learning courses to meet the needs of individual learners. A review of the literature reveals that teachers can use technology to customize the learning experience for each student (Collins and Halverson, 2010), yet the school principal holds the power to execute new school-wide initiatives to embrace personalized learning through online courses (McLeod, Bathon, and Richardson, 2011). The purpose of this study was to examine the process of redeveloping digital content with personalized learning pathways with a focus on the role of the school principal. This study was guided by the following research questions: (1) what are the instructional leadership decisions and actions of an online school principal to launch the creation and development of personalized digital content? (2) what are the course developers’ perceptions of the impact of leadership behaviors on designing and implementing personalized digital content? This qualitative case study was conducted in one district-led online school in a large urban school district in the Southeast region of the United States. Data were collected through interviews, observations, and a review of documents. Participants included the principal, an assistant principal, three technology coordinators, and three teacher/course developers. Data were organized into three pre-determined categories based on Hallinger and Murphy’s (1985) instructional leadership framework - defining the school’s mission, managing the instructional program, and promoting a positive school learning climate. Three key themes emerged from the data – (1) aligning the initiative with the school’s goals, (2) providing necessary resources, and (3) empowering teachers and students. These three themes highlight the potential impact of online school principals on creating digital content with a personalized learning approach. Findings from this study contribute to the research on online learning, personalized learning, and instructional leadership

New approaches to fiber optic chemical sensors for ions

Two problems of current fiber optic chemical sensors (FOCS) were addressed in this research. First, an immobilized ligand was characterized as a possible reagent for detecting anions selectively. Second, a new approach to fiber optic chemical sensing based on polymer swelling was demonstrated. The immobilized reagent explored for selective detection of anions is marketed as tris(carboxymethyl) ethylenediaminediacetic acid (TED). Characterization of this reagent showed that it is actually a mixture of ligands with ethylenediaminediacetic acid (EDDA) being the major species. Conclusive evidence was found in the EPR spectra. Several model ligands including a sample of TED from a private source were compared to the commercial product. EPR spectrum of the commercial reagent most resembled the EDDA spectrum. Theoretical and experimental capacities and conditional complexation constant of immobilized ligand for Cu(II) were measured and found to be consistent with this interpretation. A new type of sensor based on polymer swelling coupled to optical displacement was demonstrated. Two commercially available bead polymers, Dowex 50W and SP Sephadex served as reagent phases for sensing ions. When the sensor is placed into an ionic solution the bead contracts. This brings a reflector in contact with the bead closer to the end of the fiber or fibers such that the intensity of the reflected light reaching the detector changes. Response is both rapid, on the order of seconds, and reversible. Both reagents detect a change in concentration of ions in solution, but the sensor based on SP Sephadex is more sensitive. Total change in the normalized reflected intensity at 400 nm for Dowex 50W is 48% and for SP Sephadex is 93%. Dynamic range was 0.100 to 1.0 M for Dowex 50W and 0.001 to 0.1 for SP Sephadex. A CM Sephadex bead polymer serves as a sensor for pH. Response is both reversible and rapid. Relative intensity changes are on the order of 10% for a pH change of 1.0 unit at 0.01 M ionic strength. An ionic strength of 0.1 reduces the response due to the change in pH. Parameters which affect the performance of the sensors include number of fibers employed, degree of crosslinking of the bead, bead diameter and salt type

Relationship of body measurements, weight, age and fatness to size and performance in beef cattle

The objectives of this study were to determine effects of cow weight, cow wither height, cow body volume, cow fat thickness, calf fat thickness, and cow size and shape indexes on 205-day weaning weight, adjusted wither height, approximate body volume, and size and shape indexes of calves. Indexes of size and shape were the result of principal-component analysis. The data consisted of weight, body measurements and fat thickness measurements of 318 Hereford and 516 Angus cows and their progeny maintained at the Alcoa Farm, The University of Tennessee, Knoxville. Body measurements collected were wither height, body length, body depth and body width. Weaning weight and all body measurements collected on calves were statistically adjusted to a 205-day age basis and were adjusted for sex of calf effects with least-squares estimates of regression obtained directly from these data. Principal-component analysis, a multivariate technique, was studied as a method to define animal size and shape. The first component for both cows and calves contrasted animals according to general size. It accounted for 56.2 and 46.9 percent of the total variation in cows and calves, respectively. The second component contrasted animals according to body shape. Total variation explained by the first two principal components was 72.5 and 67.2 percent for cows and calves, respectively. All correlations among cow body measurements and measures of size, and among calf body measurements and measures of size were highly significant (P\u3c.01). Adjusted 205-day weight and calf wither height were highly correlated (P\u3c.01) with the cow measurements and measures of size. Calf volume was significantly (P\u3c.01) correlated with the cow variables. Principal component indexes for size and shape of calves were generally highly correlated (P\u3c.01) with the cow variables. Calf fat thickness was correlated (P\u3c.01) with all cow variables except cow fat thickness, however the correlations were not as large as those with indicators of calf size. Stepwise multiple regression analysis indicated that calf fat thickness and cow weight controlled the most variation in 205- day weaning weight. Effects of year, breed and cow age also were included in the model as discrete variables, as they were in all regression equations. Independent variables exhibiting the most pronounced effects on calf wither height were calf fat thickness and cow wither height. Calf fat thickness was indicated as the only significant effect on calf volume. Coefficients of determination (R2) of calf weight, wither height, and volume ranged from 39.7 to 42.9 percent. Independent variables with the greatest effects on calf size index were calf fat thickness, cow weight and cow shape index. Calf fat thickness and cow height were the first effects to enter the equation describing the regression of calf shape index on the cow variables. Coefficients of determination from analyses of calf size and shape indexes were 55.7 and 67.0 percent, respectively. These analyses indicated that cow weight, cow wither height and calf fat thickness had the most pronounced effects on the measures of calf size and performance

Beauty Through Control: Forming Pro-Anorexic Identities in Digital Spaces

Pro-anorexia is a complex, multi-layered phenomenon that exists only online. The women who participate in these websites are learning to negotiate how to manage an identity that is normalized within the group but stigmatized within larger society. Using an open-ended survey, distributed online directly to pro-ana website users, I aim to illustrate pro-anorexic experience. After a brief demographic sketch of typical pro-anorexic spaces, I examine pro-anorexia in depth by asking three primary research questions: 1) how do pro-anorexics craft their online identities within the community; 2) how do individuals interact with one another in a highly contested and heavily policed online social world; and 3) how does a counterculture negotiate its relationship with larger society? In asking these three questions, I am extending current academic understandings of pro-anorexia by spotlighting what pro-ana is in the words of the women who use these websites and engage in disordered eating behaviors

Monocyte-Derived Dendritic Cells Exhibit Increased Levels of Lysosomal Proteolysis as Compared to Other Human Dendritic Cell Populations

Fine control of lysosomal degradation for limited processing of internalized antigens is a hallmark of professional antigen presenting cells. Previous work in mice has shown that dendritic cells (DCs) contain lysosomes with remarkably low protease content. Combined with the ability to modulate lysosomal pH during phagocytosis and maturation, murine DCs enhance their production of class II MHC-peptide complexes for presentation to T cells.In this study we extend these findings to human DCs and distinguish between different subsets of DCs based on their ability to preserve internalized antigen. Whereas DCs derived in vitro from CD34+ hematopoietic progenitor cells or isolated from peripheral blood of healthy donors are protease poor, DCs derived in vitro from monocytes (MDDCs) are more similar to macrophages (M Phis) in protease content. Unlike other DCs, MDDCs also fail to reduce their intralysosomal pH in response to maturation stimuli. Indeed, functional characterization of lysosomal proteolysis indicates that MDDCs are comparable to M Phis in the rapid degradation of antigen while other human DC subtypes are attenuated in this capacity.Human DCs are comparable to murine DCs in exhibiting a markedly reduced level of lysosomal proteolysis. However, as an important exception to this, human MDDCs stand apart from all other DCs by a heightened capacity for proteolysis that resembles that of M Phis. Thus, caution should be exercised when using human MDDCs as a model for DC function and cell biology

LaTeX, metadata, and publishing workflows

The field of scientific publishing that is served by LaTeX is increasingly dependent on the availability of metadata about publications. We discuss how to use LaTeX classes and BibTeX styles to curate metadata throughout the life cycle of a published article. Our focus is on streamlining and automating much of publishing workflow. We survey the various options and drawbacks of the existing approaches and outline our approach as applied in a new LaTeX style file where we have as main goal to make it easier for authors to specify their metadata only once and use this throughout the entire publishing pipeline. We believe this can help to reduce the cost of publishing, by reducing the amount of human effort required for editing and providing of publication metadata