Studies on Carbohydrate Metabolism in Normal and Diabetic Rats.

The specific activities of phosphofructokinase, aldolase, and pyruvate kinase was diminished in crude extracts from skeletal muscle of streptozotocin diabetic rats, whereas the activities of glucosephosphate isomerase and phosphoglucomutase were not changed. The decreased phosphofructokinase activity was shown to be independent of allosteric control, and it could be reversed by insulin treatment. A rapid and mild method for the purification of phosphofructokinase from rat skeletal muscle were developed. The partially purified enzyme from muscle of normal and streptozotocin diabetic rats showed identical Michaelis constants for ATP and equal sensitivity to inhibition by excess of ATP. Extracts of quick-frozen muscle from diabetic rats had higher levels of citrate, and lower levels of fructose 1,6-bisphosphate and glucose 1,6-bisphosphate. The levels of fructose 6-phosphate, glucose 6-phosphate, ATP, ADP, and AMP were the same for the two groups. These data suggest that phosphofructokinase activity is decreased in muscle of diabetic animals due to (a) a decrease in extractable activity, when assayed under optimum conditions, and (b) an unfavorable change in the levels of some of its allosteric modulators. A precise and reproducible gas chromatographic procedure for the determination of anomeric composition of glucose in biological fluids was developed. When applied to blood, peaks of the silylated glucose anomers were well resolved and were the only two major peaks found in blood. Blood glucose of normal and alloxan-diabetic rats, fed or fasted, was found statistically to have an anomeric composition slightly favoring the (beta) anomer over the thermodynamic equilibrium composition in water (39.1 (+OR-) 0.6% (alpha)- and 60.9 (+OR-) 0.6% (beta)-). The anomeric composition of glucose in plasma as well as in whole blood remained close to equilibrium after the administration of insulin to normal or diabetic rats. However, there was a statistically noticeable decrease in the percentage of blood (beta)-glucose as a result of insulin treatment of normal animals. A spin echo nuclear magnetic resonance technique for the non-invasive measurement of glycolytic activity in red blood cells from normal and diabetic rats was used. No differences were seen between the two groups. Proton magnetic resonance spectra of serum from normal and diabetic rats were also similar

A Magnet System Implementation of the Hester Davis Fall Reduction Program

A Magnet-recognized academic hospital system experienced an increase in patient falls and patient falls with injury after transitioning to a new electronic health record. The purpose of the project was to evaluate the effectiveness of a system-wide quality improvement practice change. The practice-focused question addressed a Magnet model implementation of a standardized, system-wide, evidence-based Hester Davis Scale (HDS) fall risk assessment and intervention tool and the impact on the nursing-sensitive indicators of patient fall rates and fall rates with injury. Successful implementation and sustained, correct use of the HDS fall risk assessment and targeted fall-prevention-intervention tools added to the evidence of multifactorial fall-intervention-prevention strategies designed to reduce patient falls and patient injury associated with falls. Two models were used to inform the project: the American Nurses Credentialing Center next-generation Magnet model and the Institute for Healthcare Improvement framework for spread. The primary source of evidence was the National Database of Nursing Quality Indicators. A run chart approach to process improvement was determined to be the best method to assess the effectiveness of the HDS Falls Prevention Program for 28 months post implementation. The run chart for patient fall rates and fall with injury rates demonstrated a reduction in falls and sustained improvement over 28 months. The decreases in falls and fall with injury rates of this project have implications for positive social change. Magnet recognition supports the implementation of the evidence-based HDS Fall Reduction Program, thereby improving the quality of life for patients and families and reducing the burden and cost of health care associated with falls

High-throughput dissolution/permeation screening : a 96-well two-compartment microplate approach

Early formulation screening can alleviate development of advanced oral drug formulations, such as amorphous solid dispersions (ASDs). Traditionally, dissolution is used to predict ASD performance. Here, a high-throughput approach is described that simultaneously screens drug dissolution and permeation employing a two-compartment 96-well plate. Freeze-drying from hydro-alcoholic solutions was used to prepare amorphous formulations. The screening approach was tested on amorphous and crystalline tadalafil formulations with and without Soluplus®. The workflow consisted of: 1) dispersion of the formulations; 2) incubation within the two-compartment plate, where a dialysis membrane separated donor (dispersed formulation) and acceptor; 3) sampling (donor and acceptor), where donor samples were centrifuged to remove non-dissolved material; and 4) quantification by UHPLC-UV. To identify optimal screening conditions, the following parameters were varied: dispersion medium (buffer / biomimetic media), acceptor medium (buffer / surfactant solutions), and incubation time (1, 3, and 6 h). Surfactants (acceptor) increased tadalafil permeation. Biomimetic medium (donor) enhanced dissolution, but not permeation, except for freeze-dried tadalafil, for which the permeated amount increased. The predictiveness was evaluated by comparing dissolution-/permeation-results with in vivo bioavailability. In general, both dissolution and permeation reflected bioavailability, whereof the latter was a better predictor. High-throughput dissolution/permeation is regarded promising for formulation screening

Deciphering petrogenic processes using Pb isotope ratios from time-series samples at Bezymianny and Klyuchevskoy volcanoes, Central Kamchatka Depression

The Klyuchevskoy group of volcanoes in the Kamchatka arc erupts compositionally diverse magmas (high-Mg basalts to dacites) over small spatial scales. New high-precision Pb isotope data from modern juvenile (1956–present) erupted products and hosted enclaves and xenoliths from Bezymianny volcano reveal that Bezymianny and Klyuchevskoy volcanoes, separated by only 9 km, undergo varying degrees of crustal processing through independent crustal columns. Lead isotope compositions of Klyuchevskoy basalts–basaltic andesites are more radiogenic than Bezymianny andesites ([superscript 208]Pb/[superscript 204]Pb = 37.850–37.903, [superscript 207]Pb/[superscript 204]Pb = 15.468–15.480, and [superscript 206]Pb/[superscript 204]Pb = 18.249–18.278 at Bezymianny; [superscript 208]Pb/[superscript 204]Pb = 37.907–37.949, [superscript 207]Pb/[superscript 204]Pb = 15.478–15.487, and [superscript 206]Pb/[superscript 204]Pb = 18.289–18.305 at Klyuchevskoy). A mid-crustal xenolith with a crystallization pressure of 5.2 ± 0.6 kbars inferred from two-pyroxene geobarometry and basaltic andesite enclaves from Bezymianny record less radiogenic Pb isotope compositions than their host magmas. Hence, assimilation of such lithologies in the middle or lower crust can explain the Pb isotope data in Bezymianny andesites, although a component of magma mixing with less radiogenic mafic recharge magmas and possible mantle heterogeneity cannot be excluded. Lead isotope compositions for the Klyuchevskoy Group are less radiogenic than other arc segments (Karymsky—Eastern Volcanic Zone; Shiveluch—Northern Central Kamchatka Depression), which indicate increased lower-crustal assimilation beneath the Klyuchevskoy Group. Decadal timescale Pb isotope variations at Klyuchevskoy demonstrate rapid changes in the magnitude of assimilation at a volcanic center. Lead isotope data coupled with trace element data reflect the influence of crustal processes on magma compositions even in thin mafic volcanic arcs.University of Washington. Department of Earth and Space Science

Correction to “Isotopic characterization of aerosol organic carbon components over the eastern United States”

Author Posting. © American Geophysical Union, 2012. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Journal of Geophysical Research 117 (2012): D15399, doi:10.1029/2012JD018478.2013-01-0

Small-volume Lu-Hf and U-Pb isotope determination of complex zircons by solution and laser ablation MC-ICP-MS

This study presents solution and laser ablation analysis methods suited to the determination of the Lu-Hf and U-Pb isotope signatures of small volumes of zircon corresponding to sub-nanogram amounts of Hf. A reduced-volume approach to laser ablation is taken with consecutive U-Pb and Lu-Hf isotopic analyses resulting in a total pit depth of 18 μm using a 25 μm laser ablation spot. This results in excavation of ~ 40 ng of zircon, equating to ~ 0.3 ng of Hf and uncertainties ~ 1 εHf (2s). The laser technique presented here is ideally suited to complex, finely-zoned zircons for which drilling to depth would intersect different zones. The possibility of reducing the total laser ablation pit depth to ~ 10 μm is demonstrated by decreasing the integration time for Hf isotope analysis without serious compromise of the uncertainty. Furthermore, the capability to determine the Hf isotope composition of the same amount of Hf using solution MC-ICP-MS is also demonstrated, as is the suitability of analyzing solutions not subject to Hf-HREE separation. For both solution and laser ablation methods, this study investigates possible methods of Yb interference correction, the potential for matrix effects, and the accurate determination of 176Lu/177Hf. Using the approaches described here, acceptable uncertainty levels are achieved to resolve complexity at the level of 25 × 18 μm (diameter × depth), and therefore this method has the potential to yield geologically meaningful results for rocks containing complexly-zoned zircons

Group Analysis in Practice: Narrative Approaches

This is the final version of the article. Available from Institut für Qualitative Forschung via the URL in this record.Working in groups is increasingly regarded as fruitful for the process of analyzing qualitative data. It has been reported to build research skills, make the analytic process visible, reduce inequalities and social distance particularly between researchers and participants, and broaden and intensify engagement with the material. This article contributes to the burgeoning literature on group qualitative data analysis by presenting a worked example of a group data analysis of a short extract from an interview on serial migration from the Caribbean to the UK. It describes the group's working practices and the different analytic resources drawn upon to conduct a narrative analysis. We demonstrate the ways in which an initial line-by-line analysis followed by analysis of larger extracts generated insights that would have been less available to individual researchers. Additionally, we discuss the positioning of group members in relation to the data and reflect on the porous boundary between primary and secondary analysis of qualitative data.With grateful thanks to the participants, without whose generosity in sharing their stories, the study would not have been possible. We are also pleased to acknowledge funding of the NOVELLA research node from the Economic and Social Research Council that enabled engagement with methodological, theoretical and substantive issues