15 research outputs found
Increased sensitivity and discrimination in screening through an immobilized-resin microbiological assay method
Problems with present bioactive microbial product screening techniques include low sensitivity and insufficient discrimination capabilities. These problems are addressed by our new immobilized-resin microbiological assay. This technique concentrates bioactive samples on macroporous polymeric resins that are immobilized in hydrogel beads. These beads are then subjected to elution in the wells of an agar diffusion microbiological assay medium. With a strong base anion exchanger, the sensitivity to ampicillin of the ÎČ-lactam-supersensitive Escherichia coli mutant ESS-22-31 was increased 10-fold. Similar increases in sensitivity were obtained in the detection of streptomycin using a weak acid cation exchanger with Bacillus subtilis and for cycloheximide by a neutral resin and Saccharomyces cerevisiae NRRL-Y-139. A judicious choice of resin type and eluent permitted a selective sensitivity increase based on the charge or hydrophobic nature of the desired product. This selectivity imparts a discrimination capability to the technique.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/47948/1/10295_2005_Article_BF01569546.pd
The James Webb Space Telescope Mission
Twenty-six years ago a small committee report, building on earlier studies,
expounded a compelling and poetic vision for the future of astronomy, calling
for an infrared-optimized space telescope with an aperture of at least .
With the support of their governments in the US, Europe, and Canada, 20,000
people realized that vision as the James Webb Space Telescope. A
generation of astronomers will celebrate their accomplishments for the life of
the mission, potentially as long as 20 years, and beyond. This report and the
scientific discoveries that follow are extended thank-you notes to the 20,000
team members. The telescope is working perfectly, with much better image
quality than expected. In this and accompanying papers, we give a brief
history, describe the observatory, outline its objectives and current observing
program, and discuss the inventions and people who made it possible. We cite
detailed reports on the design and the measured performance on orbit.Comment: Accepted by PASP for the special issue on The James Webb Space
Telescope Overview, 29 pages, 4 figure
Odorous childhoods and scent(ed) worlds of learning: A sensory history of health and outdoor education initiatives in Western Europe (1900s-1960s)
This paper develops a sensory history of health and outdoor education initiatives which featured (non-)formal schooling, analyzing these as belonging to (a) scent(ed) and more generally sense(d) world(s) of learning. Working with photographs as sensory objects of affect, and using as examples Belgian and Luxembourg open-air schools and associated sanitary and social welfare provisions, the paper explores issues so far under-researched in sensuous scholarship internationally: those of precise educational purposes, methods, processes and effects of sensory engagement, particularly pertaining to âsmellâ. Sensory practices and experiences and uses of senses generally are thereby traced in/as âsituated, embodiedâ movements inextricably âenmeshedâ with symbolism. The paper argues that while the educational goals underpinning the initiatives investigated and the approaches and practices characterizing these have changed, some (un)intended effects still have an impact today, for instance through Forest School as given shape in the United Kingdom. The concept of âodorousâ, or rather âsensuous childhoodsâ, is proposed to denote ways that particular target groups have come to be imagined as in need of explicitly sensorial health and outdoor education
Daily Forecasts of Columbia River Plume Circulation: A Tale of Spring/Summer Cruises
Semi-operational daily forecasts of circulation from an observatory for the Columbia River estuary-plume-shelf system routinely support oceanographic cruises, by providing 24h-ahead estimates of plume location and structure for planning purposes and for near real-time interpretation of observations. This paper analyzes forecast skill during spring/summer cruises in 2004-2007. Assessment addresses both qualitative descriptions of major plume trends and features and quantitative representation of data from (primarily) vessel-based flow-through, cast and towed systems. Forecasts emerge as robust predictors of plume location and variability, with skill that has grown over time, at least in part due to improvements in model algorithms. When the same version of SELFE is used as the common computational engine, forecast skill is very comparable to the skill of multi-year simulation databases, which are computed retrospectively. As a measure of forecast skill, 55% of the predictions of surface salinities came within 2 km of observations, and directional shifts in response to coastal winds were well predicted. Quantitative skills for other aspects of the plume structure vary. Skill is highest for flow-through (and near-surface TRIAXUS) salinities. Forecasts also capture aspects of the vertical structure of the plume as represented by CTD casts (undulating TRIAXUS). Sub-tidal velocities, as compared against fixed station data, are least well described among examined variables. Overall, circulation forecasts help level the playing field among chief scientists with diverse disciplinary expertise. The chief scientist?s expertise on plume physics determines whether forecasts should be used for training and land-assisted planning, or as a sophisticated en route planning and interpretation tool. Effective interpretation of vessel observations in context of forecasts requires understanding of physical processes and modeling limitations
Artemisinin-acetylenedicarboxylic acid cocrystal: screening, structure determination, and physicochemical property characterisation
The file attached to this record is the author's final peer reviewed version. The Publisher's final version can be found by following the DOI link.Artemisinin is used to treat malaria, even when caused by multi-drug resistant strains of the Plasmodium parasite; the compound also shows good promise as an anti-cancer drug. However, the usage of artemisinin is limited due to its low aqueous solubility. Herein a large scale of cocrystal screening of artemisinin was conducted using both computational and experimental approaches, resulting in a new 2:1 artemisinin and acetylenedicarboxylic acid (ART2-ACA) cocrystal. ART2-ACA crystallises in the P 212121 space group of an orthorhombic system with the cell parameters a = 10.5089 Ă
, b = 24.083 Ă
, c = 6.4952 Ă
. The asymmetric unit of the cocrystal contains two ART molecules and a single ACA molecule, assembled into discrete trimeric units held together by two supramolecular heterosynthons. It was shown that ART2-ACA cocrystals are of higher solubility and faster dissolution rate compared to the parent drug of artemisinin
Short-Term Impacts of Military Overflights on Caribou During Calving Season
The Fortymile Caribou Herd (FCH) is the most prominent caribou herd in interior Alaska. A large portion of the FCH calving and summer range lies beneath heavily used Military Operations Areas (MOA) that are important for flight training. We observed the behavior of Grantâs cow caribou (Rangifer tarandus granti) and their calves before, during, and immediately following low-level military jet overflights. We also monitored movements of radiocollared cow caribou and survival of their calves. We conducted fieldwork from mid May through early June 2002. We concluded that military jet overflights did not cause deaths of caribou calves in the FCH during the calving period nor result in increased movements of cowâcalf pairs over the 24-hour period following exposure to overflights. Short-term responses to overflights were generally mild in comparison to caribou reactions to predators or perceived predators. Caribou responses to overflights were variable, but responses were generally greater as slant distances decreased and jet speeds increased. A-10 jets caused less reaction than F-15s and F-16s. Although we found that short-term reactions of caribou to jet overflights were mild, we advise against assuming there are no long-term effects on calving caribou from jet overflights