Effects of Adding Sodium and Fluoride Ions to Glass Ionomer on its Interactions with Sodium Fluoride Solution

This investigates the effects of the addition of Na and F ions to a glass ionomer cement in which those ions are not inherently present on its interactions with dilute (0.2%) NaF solution. Both the effect of the solution on the cement\u27s surface morphology and the effect of the cement on the solution in terms of take up of Na+ and F- and of change in pH are to be investigated. These results are to be compared to previous results obtained with glasses which contained both, one, or neither of the ions as components of their glasses. NaF (1.3% by weight in the mixed cement) was added to the powder components of a glass ionomer based on LG30 glass (which contains Al, Si, Ca, P, and O only). Discs of cement were set in moulds at 37°C for 1h then stored in water at 37°C for 3 days. Each test disc was then immersed in 10ml 0.2% NaF solution whereas controls remained immersed in water (N=3 for test and control). Test and control disc surfaces were assessed both qualitatively by electron microscopy and quantitatively by linear profilometry (R(a) values). Potentiometry was used to measure solution pH and Na and F concentrations using a pH electrode and suitable ion selective electrodes both before and after cement immersion. The surface of test specimens was subject considerable disruption with the polysalt cement matrix being removed and residual glass particles being disclosed. The controls showed no such disruption. This effect was reflected in a significant difference of R(a). Such an effect was not shown by test and control surfaces of LG30 but a similar effect was to that shown by LG26 (which contains F as a glass component). Solution pH changed by 1 unit which was much more than the change shown by LG30 or LG26 but is similar to that of AH2 and MP4 cements which both contain Na. The Na and F uptake was much lower than for LG30 whereas that of LG26 was higher than LG30. The Na:F ratio was 0.29:1 compared to 1.26:1 for LG30 (LG26=1.01:1, AH2=1.02:1, MP4=1.04:1). Fluoride addition to a F-free glass ionomer renders it vulnerable to surface disruption by NaF solution showing that fluoride complexes produced in glass dissolution are not necessarily involved in this process. Sodium addition to a Na-free glass ionomer confirms the role of this cement in enhancing pH change in NaF solution. The level of uptake of F- from a NaF solution in much lower than that for the F-free glass ionomer which shows there is no direct relationship between F- uptake and surface disruption. The ratio of Na:F uptake is below 0.3:1, but the pH change is similar to cements where the ratio is close to unity which indicates that F-/OH- interchange is not a significant mechanism even when anion/cation uptake is not balanced. Copyright (C) 2000

New England Intercollegiate Geological Excursion: Littleton, New Hampshire, October 10, 11 and 12, 1936

Trip A: Littleton quadrangle and northwest corner of the Moosilauke quadrangle; Trip B: Moosilauke quadrangle; Trip C: Mt. Hale, northeast corner of the Franconia quadrangl

The osteological evidence for execution in Anglo-Saxon England

YesThis paper reviews the osteological evidence for execution in Anglo-Saxon England, which, in the cases of modern analysis, can reveal considerable detail about the methods of decapitation, in particular, and it also provides a critical appraisal of the considerably less reliable antiquarian reports. We suggest that secure evidence for execution, principally decapitation, can be identified through modern osteological analysis but it is limited, and we also argue that assertions made in antiquarian excavation reports about apparent examples of execution need to be treated with caution

Partnerships and Public Service: Normative Issues for Journalists in Converged Newsrooms

As media companies test and implement newsroom “convergence,” growing numbers of journalists are producing content not only for their own employer but also for other media outlets with which that employer has a business relationship. This article, based on case studies in four converged news markets, explores journalists’ perceptions of normative pressures in this new media environment, particularly in relation to the overarching concept of public service. The findings suggest that although journalists do not see convergence itself as posing significant ethical problems, they do raise concerns related to specific components of public service, including a devotion to accuracy, an avoidance of sensationalism, and independence from economic pressures

The Effect of Increasing Valine, Isoleucine, and Tryptophan:Lysine Ratios on Pigs’ Growth Performance and Carcass Characteristics When Fed Diets with Increased Levels of Dietary Leucine:Lysine

A total of 4,076 pigs (initially 86.5 ± 1.24 lb) were used across 2 experiments to evaluate the effect of increasing ratios of Val, Ile, and Trp to Lys on pig growth performance and carcass characteristics in corn-soybean meal-DDGS-based diets containing increased levels of dietary Leu:Lys. In both experiments, the 4 dietary treatments were as follows: 1) high soybean meal and low feed grade amino acids (control); 2) low soybean meal and high feed grade amino acids, with Val:Lys, Ile:Lys, and Trp:Lys at 67, 55, and 18, respectively, (low ratio); 3) same as diet 2 except Val:Lys, Ile:Lys, and Trp:Lys increased to 72, 60, and 21, respectively, (medium ratio); and 4) same as diet 2 except Val:Lys, Ile:Lys, and Trp:Lys increased to 80, 65, and 23, respectively (high ratio). All diets contained 30% DDGS until pigs reached approximately 220 lb, and then 20% DDGS until trial completion. Overall ADG and average ADFI increased (AA ratio; linear, P \u3c 0.05) as Val, Ile, and Trp ratios increased from low to high. Pigs fed the control diet exhibited increased ADG when compared to pigs fed low ratio diets, while pigs fed medium and high ratio diets showed intermediate performance. In summary, the soybean meal level can be reduced, and synthetic amino acid levels increased in high DDGS diets as long as ratios of Val, Ile, and Trp to Lys are increased

Robert Nozick on nonhuman animals : rights, value and the meaning of life

In his chapter, Josh Milburn argues that Robert Nozick considers nonhuman animals in his philosophical writings, but that these discussions are downplayed in animal ethics and Nozick scholarship. This is regrettable, Milburn proposes, as Nozick is far more sympathetic to animal rights than many other libertarians. Milburn thus offers an analysis of Nozick’s animal ethics. Nozick’s arguments concerning vegetarianism and speciesism are considered, and Milburn argues that tensions in Nozick’s political philosophy potentially open the door to animal rights. Whatever their place in his political philosophy, Milburn contends, nonhuman animals find a comfortable home in Nozick’s axiology and ethics, with their value and the significance of our duties towards them affirmed. Milburn concludes that animal ethicists could learn from Nozick’s distinctive arguments and approaches and find an unexpected ally

Diagnostic Survey of Biological Measurements Used to Determine Bone Mineralization in Pigs Across the US Swine Industry

Pigs from 64 commercial sites across 14 production systems in the Midwest US were used to evaluate the baseline biological measurements used to determine bone mineralization. Three pigs were selected from each commercial site representing: 1) a clinically normal pig (healthy); 2) a pig with evidence of clinical lameness (lame); and 3) a pig from a hospital pen that is assumed to have recent low feed intake (unhealthy). Pigs ranged in age from nursery to market weight, with the three pigs sampled from each site representing the same age or phase of production. Blood, urine, metacarpal, fibula, 2nd rib, and 10th rib were collected and analyzed. Serum was analyzed for Ca, P, and 25(OH)D3, and urine was collected and analyzed for Ca, P, and creatinine. Each bone was measured for density, ash (defatted and non-defatted technique), and breaking strength. A bone × pig type interaction (P \u3c 0.001) was observed for defatted and non-defatted bone ash, density, and breaking strength. For defatted bone ash, there were no differences (P \u3e 0.10) between pig types for the fibulas, 2nd rib, and 10th rib, but metacarpals from healthy pigs had greater (P \u3c 0.05) percentage bone ash compared to unhealthy pigs, with the lame pigs intermediate. For non-defatted bone ash, there were no differences (P \u3e 0.10) between pig types for metacarpals and fibulas, but unhealthy pigs had greater (P \u3c 0.05) non-defatted percentage bone ash for 2nd and 10th ribs compared to healthy pigs, with lame pigs intermediate. Healthy and lame pigs had greater (P \u3c 0.05) bone density than unhealthy pigs for metacarpals and fibulas, with no difference (P \u3e 0.10) observed for ribs. Healthy pigs had bones with increased breaking strength compared to lame and unhealthy pigs for metacarpals and 10th ribs (P \u3c 0.05) with no differences (P \u3e 0.05) between pig types for fibula and 2nd rib. Healthy pigs had greater (P \u3c 0.05) serum Ca and 25(OH)D3 compared to unhealthy pigs, with lame pigs intermediate. Healthy pigs had greater (P \u3e 0.05) serum P compared to unhealthy and lame pigs, with no differences (P \u3e 0.05) between the unhealthy and lame pigs. Unhealthy pigs excreted more (P \u3c 0.05) P and creatinine in the urine compared to healthy pigs, with lame pigs intermediate. In summary, there are differences in serum Ca, P, and vitamin D between healthy, lame, and unhealthy pigs. Differences in bone mineralization between the pig types varied depending on the analytical procedure and bone. There was a considerable range in values within pig type across the 14 production systems sampled

Exercise and Health: Can Biotechnology Confer Similar Benefits?

Education and public policies are largely failing to encourage people to exercise. Could our knowledge of exercise biology lead to pharmaceutical treaments that could confer the same benefits as exercise

Determining the Phosphorus Release Curve for Smizyme TS G5 2,500 Phytase from 500 to 2,500 FTU/kg in Nursery Pig Diets

A total of 320 pigs (DNA 241 × 600; initially 26.2 ± 0.48 lb BW) were used in a 21-d growth study to determine the available P (aP) release curve for Smizyme TS G5 2,500 (Barentz, Woodbury, MN). At approximately 19 d of age, pigs were weaned, randomly allotted to pens, and fed common starter diets. Pigs were blocked by average pen body weight (BW) and randomly allotted to 1 of 8 dietary treatments on d 18 post-weaning, considered d 0 of the study. Dietary treatments were derived from a single basal diet and ingredients including phytase, monocalcium P, limestone, and sand were added to create the treatment diets. Treatments included 3 diets containing increasing (0.11, 0.19, and 0.27%) inorganic P from monocalcium P, or 5 diets with increasing phytase (500, 1,000, 1,500, 2,000, or 2,500 FTU/kg) added to the diet containing 0.11% aP. All diets were corn-soybean meal-canola meal-based and were formulated to contain 1.24% SID Lys and an analyzed Ca:P ratio of 1.10:1. Prior to the beginning of the study, all pigs were fed a diet containing 0.11% aP for a 2-d period (d 16 to 18 post-weaning). At the conclusion of the study, 1 pig, closest to the mean weight of each pen, was euthanized and the right fibula, rib, and metacarpal were collected to determine bone ash, density, and total bone P. For the overall experimental period, pigs fed increasing inorganic P had improved (quadratic, P ≤ 0.053) ADG, ADFI, F/G, and final BW. Pigs fed increasing phytase had improved (quadratic, P ≤ 0.004) ADG, F/G, and final BW and increased (linear, P = 0.019) ADFI. For fibula, rib, and metacarpal characteristics, pigs fed increasing levels of aP from inorganic P had increased (linear, P \u3c 0.001) bone ash weight, bone ash percentage, bone density, and bone P. Additionally, pigs fed increasing phytase had increased (P \u3c 0.05) bone ash weight, bone ash percentage, bone density, and bone P in either a linear or quadratic manner depending upon bone. The available P release curve generated for Smizyme TS G5 2,500 for percentage bone ash is: aP = (0.219 × FTU) ÷ (993.238 + FTU)