Browsing by Subject "Absorption"

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    Evaluation of water sorption and solubility behavior of nine different polymeric luting materials
    (2009) Alsheikh, Rasha N.; Platt, Jeffrey A.; Lund, Melvin R., 1922-; Cochran, Michael A. (Michael Alan), 1944-; Moore, B. Keith; Matis, Bruce A.
    The cementation procedure is the key to long-term success of fixed restorations. The prognosis of prosthetic restoration is largely impacted by the maintenance of the luting cement and the adhesive bond. When exposed to water or saliva, most restorative materials undergo hydrolytic degradation. The purpose of this study is to evaluate the water solubility and water sorption characteristics of newly introduced acidic polymeric luting agents over a 180-day water-storage period. Nine different luting agents were tested. Fifty-two disc specimens of each material were fabricated using a mold with an internal dimension of 15[plus-minus]0.1 mm in diameter and 1.0 [plus-minus]0.1 mm deep. A constant weight, W0 [subscript zero], was reached after desiccating the specimens. Then, 13 specimens were assigned randomly to one of the four testing periods in the water for seven, 30, 90 and 180 days. After each period, the specimens were removed from the water and weighed to get W1 [subscript one]. A second period of desiccating the samples provided a constant weight W2 [subscript two]. The water sorption and solubility were determined by the following equations: WSP [subscript SP](%) = (W1 [subscript one] W2 [subscript two] ) X 100/ W0 [subscript zero] ,WSL [subscript SL](%) = (W0 [subscript zero] W2 [subscript two) X 100/ W0 [subscript zero]. The resin-modified glass-ionomers showed the highest water sorption/solubility results. The resin luting agents had the lowest sorption/solubility results. The self-adhesives showed a wide range of solubility/sorption; in general, they showed lower results compared with the resin-modified glass-ionomers. All the materials reached some sort of equilibrium after 90-days. Based on the results of our study, we conclude that self-adhesive luting materials were not all alike. Rely X Unicem was the most comparable to the resin luting materials. The resin luting materials had the lowest solubility and sorption. Resin-modified glass-ionomers showed the highest sorption/solubility results.
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    Factors that Facilitate and Inhibit Engagement of Registered Nurses: An Analysis and Evaluation of Magnet versus Non-Magnet Designated Hospitals
    (2012-03-16) Wonder, Amy C.; Fisher, Mary L., Ph.D.; Pesut, Daniel J.; Ebright, Patricia; Halstead, Judith A.
    Work engagement of registered nurses (RNs) has gained attention in health care, as an organizational process that is requisite to promoting optimal patient outcomes. Improving patient outcomes has caused a movement to examine what can be done to bridge the disparity between good and excellent care. Standards that enhance RN engagement to promote professional care are seen as vital to excellence. Magnet designation, awarded by the American Nurses Credentialing Center, signifies an organization meets such standards. Therefore, the purpose of this study was to evaluate whether a correlation exists between RN engagement and the organizational structures common to Magnet designation. This study also evaluated the influence of social and institutional demographics on the relationship between engagement and Magnet designation. The variables in this study included: age (generation), gender, nursing degree, years of RN experience, years of unit longevity, shift, hours scheduled and worked per week, percentage of time in direct patient care, nursing unit, and shared governance council participation. Finally, this study evaluated the influence of RN perception related to organizational support for work on the relationship between engagement and Magnet designation. A total of 370 RNs in Magnet (n = 220) and non-Magnet (n = 150) designated hospitals completed a 17-item engagement survey and a 15-item demographic survey. Major findings of the study indicated no significant difference in RN engagement between nurses who work at Magnet versus non-Magnet designated hospitals. Within the Magnet sample, significant relationships were found between engagement and shift, years of RN experience in any clinical setting, and RN perceptions related to organizational support for work. Scatter plots for nursing experience showed positive slopes for total engagement, vigor, dedication, and absorption. Post-hoc results for RN perception related to organizational support for work identified the significant areas of engagement were total engagement, vigor, and absorption. No significant post-hoc results were noted for the variable of shift. Through significant and non-significant findings, several insights were gained about engagement. As a result of this study, leadership can better assess the needs of the RN workforce to provide what RNs perceive to be important to professional practice and RN engagement.