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S Prevost

Publications and source records attributed to S Prevost.

12 recordsLinked to original sources
PubMed2006

Aqueous block copolymer-surfactant mixtures and their ability in solubilizing chlorinated organic compounds. A thermodynamic and SANS study.

Within the topic of surfactant enhanced solubilization of additives sparingly soluble in water, volumetric, solubility, conductivity, and small-angle neutron scattering (SANS) experiments on mixtures composed of alpha,omega-dichloroalkane, surfactant, copolymer, and water were carried out at 298 K. The triblock copolymers (ethylene oxide)132(propylene oxide)50(ethylene oxide)132 (F108) and (ethylene oxide)76(propylene oxide)29(ethylene oxide)76 (F68) were chosen to investigate the role of the molecular weight keeping constant the hydrophilic/hydrophobic ratio. The selected surfactants are sodium decanoate (NaDec) and decyltrimethylammonium bromide (DeTAB) with comparable hydrophobicity and different charged heads. The alpha,omega-dichloroalkanes were chosen as contaminant prototypes. For the water + surfactant + copolymer mixtures, both the volume and the SANS results straightforwardly evidenced that (1) monomers of NaDec and copolymer unimers generate small mixed aggregates, (2) monomers of DeTAB combined with copolymer unimers do not form aggregates, and (3) unimeric copolymer is solubilized into NaDec and DeTAB micelles. The alpha,omeaga-dichloroalkanes presence induces the F108 aggregation even at very low copolymer composition. The addition of surfactant disintegrates the F108 aggregates and, consequently, the additive is expelled into the aqueous phase. Once F108 is in the unimeric state, it forms copolymer-micelle aggregates which incorporate the oil. In the case of F68 both the volumetric and the SANS data reveal that the additive does not alter the copolymer unimeric state. Moreover, they show that for the aqueous DeTAB-F68 system the additive trapping in both the copolymer-micelle aggregate and the pure micelles takes place being enhanced in the former aggregate in agreement with solubility experiments. For the NaDec-F68 mixtures, an additional solubilization process in the premicellar copolymer-surfactant microstructures occurs. SANS and conductivity data show that the additive incorporation into the mixed and the pure micelles does not essentially influence the structural properties of the aggregates.

Journal Article↗
PubMed2005

Application of stable carbon isotope analysis to the detection of 17beta-estradiol administration to cattle.

The use of anabolic agents in food producing animals is prohibited within the EU since 1988 (96/22/EC directive). The control of the illegal use of natural steroid hormones in cattle is still an exciting analytical challenge as far as no definitive method and non-ambiguous analytical criteria are available. The ability of gas chromatography/combustion/isotope ratio mass spectrometry (GC/C/IRMS) to demonstrate the administration of 17beta-estradiol to bovine has been investigated in this paper. By comparison of 13C/12C isotopic ratio of main urinary estradiol metabolite, i.e. 17alpha-estradiol, with two endogenous reference compounds (ERCs), i.e. dehydroepiandrosterone (DHEA) and 5-androstene-3beta,17alpha-diol, the differentiation of estradiol metabolite origin, either endogenous or exogenous, has been proved to be achievable. After treatment, the delta(13)C(VPDB)-values of 17alpha-estradiol reached -27 per thousand to -29 per thousand, whereas delta13CVPDB-values of DHEA remained between -13 per thousand and -20 per thousand depending on the diet, maize and grass, respectively. A significant difference of delta13CVPDB between ERCs and 17alpha-estradiol was measurable over a period of 2 weeks after estradiol ester administration to the animal.

Androstenediol↗
PubMed1997

Case management of critically ill elders: a case study.

As the number of elderly increase, new challenges for the management of their health care arise. Elders who become critically ill are one of the most complex subsets of this population. Their special needs, risk factors, and diminished resources create a demand for comprehensive and creative approaches to care management. The purpose of this article is to explore the needs of the critically ill elderly and the role of nursing case management in meeting these needs. A case study approach is used to illustrate typical needs, interventions, and outcomes.

Aged↗
PubMed1997

Experiences of a nursing ethics forum. Case studies and outcomes.

Nursing staff members should need few rules and should focus on using critical thinking to guide nursing practice and care. Nurses are decision makers participating in collaborative practice. A high degree of professionalism, responsibility, and accountability is expected. We feel that this program has succeeded not only in meeting the mission and vision of the department of nursing but also that of the hospital. It also has developed to promote the philosophy that nurses must be committed to providing excellence in patient care. In addition to developing this group concept as a model, our intention is to assist staff members with the continued expansion of the group and its tenets. As Uustal asserted, the knowledge of ethical theories and principles can stimulate the nurse's thinking, and ethical decision making can offer direction; however, only you can make ethical decisions. We hope to continue the development of clinical, ethical decision-making skills and to promote the value of this program to the ongoing growth and development of professionalism in nursing.

Decision Making↗
PubMed1995

The relationship of the 6-min walk test to maximal oxygen consumption in transplant candidates with end-stage lung disease.

STUDY OBJECTIVE: To assess the relationship of distance ambulated during the 6-min walk test (6'WT) to maximal oxygen consumption (VO2 max). DESIGN: Multivariate analysis of patient characteristics to VO2 max. SETTING: Pre-lung transplant evaluation. PATIENTS: 60 patients (22 men, 38 women; mean age, 44 years) with end-stage lung disease (mean FEV1 and forced vital capacity of 0.97 and 1.93, respectively). MEASUREMENTS AND RESULTS: The 6'WT was performed on a level hallway surface, and VO2 max was obtained during maximal cycle ergometry exercise testing with respiratory gas analysis. Multivariate analysis of patient characteristics (age, sex, weight, FEV1, FVC, diffusing capacity for carbon monoxide (DCO), 6'WT distance ambulated, number of rests per 6'WT, and the maximal heart rate, blood pressure, rate-pressure product, respiratory rate, oxygen saturation, rating of perceived exertion, and amount of supplemental oxygen used during the 6'WT) was performed on two groups of 30 patients each (group A or B) who were randomly assigned to either group by a process of random selection using a computer-generated random numbers program. Distance ambulated was the strongest independent predictor of VO2 max (r = 0.73; p < 0.0001) in both groups, and adding age, weight, and pulmonary function test results (FVC, FEV1, and DCO) to the regression equation increased the correlation coefficient to 0.83. Because of the significant correlation of distance ambulated during the 6'WT to VO2 max, the prediction equation obtained from the multivariate analysis of group A, VO2 max = 0.006 x distance (feet) +3.38, was used to estimate the VO2 max of the group B patients. No significant difference was observed between the estimated (x +/- SD = 8.9 +/- 2.4 mL/kg/min) and observed (x +/- SD = 9.4 +/- 3.8 mL/kg/min) VO2 max (mean difference, 0.5 mL/kg/min; SD of the difference = 2.88). CONCLUSIONS: The distance ambulated during a 6'WT can predict VO2 max in patients with end-stage lung disease. The addition of several patient characteristics can increase the ability to predict VO2 max and account for more of the variability. Such information is valuable when assessing patient response to therapeutic intervention if respiratory gas analysis is unavailable or impractical.

Blood Gas Analysis↗
PubMed1994

Reviews and summaries of research related to AACN 1980 research priorities: contextual topics.

This article reviews and summarizes the research conducted following publication of the 1980s American Association of Critical-Care Nurses' contextual research priorities. Reports of original research conducted on the contextual priority topics between 1981 and 1991 were included. Review articles, doctoral dissertations, theses, and abstracts were excluded unless judged to provide important information on the topic. Following the statement of each priority, progress in the area is summarized. Limitations and measurement issues are discussed as appropriate. Recommendations for future research are provided, and progress in the area is summarized.

Academic Dissertations as Topic↗
PubMed1993

Reviews and summaries of research related to AACN 1980 research priorities: clinical topics.

This article reviews and summarizes the research conducted following publication of the 1980s American Association of Critical-Care Nurses' clinical research priorities. Original research conducted on the clinical priority topics between 1981 and 1991 was included. Review articles, doctoral dissertations, theses and abstracts were excluded unless judged to provide important information on the topic. Following the statement of each priority, progress in the area is summarized. Limitations and measurement issues are discussed as appropriate. Recommendations for future research are provided, and progress in the area is summarized.

Clinical Nursing Research↗
PubMed1993

Determining AACN's research priorities for the 90s.

The American Association of Critical-Care Nurses completed a three-phased process of priority identification for critical care nursing research. In phase 1, a 78-item survey was generated following a comprehensive review of potential research topics. In phase 2, approximately 1000 critical care nurses rated each item on the survey for importance to critical care nursing. Based on these results, the AACN Research Committee formulated a clinical and a nonclinical (contextual) list of research topics. Each list contained 25 topics. In phase 3, topics were given final rankings at a 1-day Consensus Conference on Research Priorities. Both Likert-type and magnitude estimation scaling were used to determine priority ranking of items on each list. As a result, both clinical and contextual research priorities were established for AACN.

Adult↗
PubMed1993

Quality of life after cardiac surgery.

Tremendous strides have been made in the surgical treatment of cardiac disease. Research has documented many physical and psychologic benefits for the patient, but many questions remain unanswered. The change in quality of life may be the single most important outcome of cardiac surgery. This issue has received considerable attention in professional literature in recent years, particularly in the midst of rapidly expanding technology and soaring health care costs. This article reviews the literature related to the quality of life of cardiac surgical patients. Specific topics, such as physiologic and psychologic outcomes, return to work, family responses, and issues related to transplant patients, are discussed. The article includes a discussion of nursing implications.

Cardiac Surgical Procedures↗
PubMed1992

Infection control practices in cardiac transplant recipients. The Research Committee, Houston-Gulf Coast Chapter of the American Association of Critical-Care Nurses.

Infection is a common cause of morbidity and mortality among transplant recipients. Infection control measures lie within the realm of nursing interventions and involve large expenditures of resources. Because transplantation is such a new specialty, few standards exist. The research question for this study was What nursing interventions are being used to prevent infection in cardiac transplant recipients? A 156-item questionnaire was developed that included isolation procedures, dressings, invasive lines, medications, staffing, staff education, dress codes, unit design, visitation, infections, length of stay, survival, and other demographic data. Content validity was established by a panel of transplant experts. After local piloting, the tool was mailed to 120 cardiac transplant centers, and 68 were returned completed. Data were analyzed using descriptive and correlational statistics. Findings revealed wide diversity in practice. Older and larger transplant programs tended to use fewer precautions. Survival rates appeared unrelated to the number of precautions used.

Heart Transplantation↗
PubMedDate not supplied

Gender differences in perceptions of quality of life in cardiac rehabilitation patients.

PURPOSE: Coronary artery disease remains the leading cause of death in the United States for both men and women. Patients actively participating in cardiac rehabilitation programs obtain both physiological and psychological benefits that have a significant positive impact on their quality of life. However, women have been underrepresented in research on cardiovascular disease and on the rehabilitation process. The purpose of this study was to determine if there were gender differences in perceptions of quality of life in cardiac rehabilitation patients. METHODS: Convenience sampling with blocking for age was used in the selection of 87 women and 87 men from 6 cardiac rehabilitation programs in Louisiana. RESULTS: Using the Ferrans and Powers Quality of Life Index--Cardiac Version, the t-test for independent samples revealed significant gender differences. Men's mean scores were significantly higher than women's mean scores on overall quality of life scores and each of the four subscales. The men's scores were significantly higher as follows: overall (P = .0026), health and functioning (P = .004), socioeconomic (P = .012), psychological/spiritual (P = .026), and family (P = .001). An additional finding indicated that men had a significantly higher number of invasive cardiac procedures (P = .0026). CONCLUSION: From the results of this study, individualized and gender-specific plans of care need to be directed at clients with cardiovascular disease.

Adult↗