A diverse collection of 14 metal−organic frameworks (MOFs) was screened for CO2 capture from flue gas using a combined experimental and modeling approach. Adsorption measurements are reported for the ...screened MOFs at room temperature up to 1 bar. These data are used to validate a generalized strategy for molecular modeling of CO2 and other small molecules in MOFs. MOFs possessing a high density of open metal sites are found to adsorb significant amounts of CO2 even at low pressure. An excellent correlation is found between the heat of adsorption and the amount of CO2 adsorbed below 1 bar. Molecular modeling can aid in selection of adsorbents for CO2 capture from flue gas by screening a large number of MOFs.
Samples prepared from H3Re3(CO)12 adsorbed on porous γ-Al2O3 were decarbonylated at 773 K in flowing H2 and characterized by X-ray absorption spectroscopy (XAS). X-ray absorption near-edge spectra ...show that rhenium in the treated sample was cationic, and extended X-ray absorption fine structure spectra show a Re−Re first-shell coordination number of approximately 2, consistent with trirhenium clusters bonded to the support. The samples were tested as catalysts for the conversion of methylcyclohexane in the presence of H2 at atmospheric pressure and at 723 and at 773 K in a flow reactor. A range of hydrocarbon products was observed, indicating the occurrence of dehydrogenation, isomerization, ring opening, and hydrocracking reactions. The catalyst used at 723 K underwent deactivation over a period of several hours, during which the selectivity for the major dehydrogenation product (toluene) increased significantly. At 773 K, the catalyst underwent activation, during which the product distribution changed. This increase in activity was retained when the temperature was reduced to 723 K, resulting in higher activity and different selectivity relative to what had been observed before at this temperature. The fresh and used catalyst samples were characterized by X-ray absorption spectroscopy, which showed that the trirhenium framework remained intact after catalysis, although changes in the rhenium coordination were observed. The catalytically active species are inferred to be trirhenium.
To determine the impact of lung transplantation on patients' function and quality of life (QOL), 10 lung transplant patients were followed from before transplantation to 3 months after ...transplantation. The following variables were examined: (1) perceived functional status; (2) respiratory function; (3) moods; (4) satisfaction with overall QOL and health; and (5) thoughts about the decision to undergo lung transplantation.
A longitudinal, small-group, repeated-measures design.
A large Midwest university medical center.
Several instruments were used to measure perceived health, QOL, functional status, and respiratory function. The perceived improvement in physical function after transplantation was accompanied by increased satisfaction with physical strength, current health, and QOL. In addition, dramatic improvements in pulmonary function were seen after transplantation (FVC, FEV1, and forced expiratory flow at 25 to 75% of FVC); however, only the FEV1 values significantly improved between 1 and 3 months after transplantation. For example, the FEV1 (mean ± SD) increased from 22 ± 11% of predicted before transplantation to 46 ± 12% and 55 ± 14% of predicted at 1 month and 3 months after transplantation, respectively. Although the total number of psychological symptoms did not decrease significantly over time, the intensity and distress associated with the symptoms did. Psychological function scores did not change significantly. Ninety percent of the subjects reported being very satisfied with their transplant decision.
Lung transplantation significantly improved the subjects' overall function and their satisfaction with their QOL and health status. However, since this report only addressed data for the first 3 months after transplantation, additional longitudinal research is needed to further elucidate the experiences and outcomes associated with lung transplantation.
Cardiothoracic transplantation's success at prolonging life--and its economic costs--must be considered relative to its psychosocial benefits and costs. Moreover, psychosocial outcomes themselves ...influence long-term post-transplant morbidity and mortality rates. Although psychosocial outcomes--encompassing patients' physical, psychologic and social functioning, their management of their medical regimen and global quality of life--are the focus of many recent studies, these investigations have yet to yield many evidence-based interventions that are routinely applied to improve patient outcomes. Our goals were to summarize existing work on psychosocial outcomes, delineate areas requiring attention, offer recommendations for steps to advance the field, and thereby provide an impetus for the conduct of clinical trials of interventions to improve these outcomes. We concluded that research must generally shift away from descriptive studies and toward prospective and clinical trial designs to: (a) examine a full range of risk factors and clinical sequelae of patients' psychosocial status; and (b) evaluate the effectiveness of psychosocial interventions. In addition, these issues must be considered across all cardiothoracic recipients, including not only heart recipients but the less-studied populations of lung and heart-lung recipients, and must include longer-term (5+ years) outcomes than is typical in most work. The importance of adequately sized samples to ensure statistical power, and the need to construct study samples representative of the larger cardiothoracic transplant population, cannot be overestimated. Implementing these changes in research design and substantive focus will ensure that psychosocial outcomes research will have maximum impact on transplant recipients' clinical care.
Purposes: To investigate symptom experiences of patients who have single and bilateral-sequential lung transplantation and to determine whether differences exist according to gender, ...pretransplantation diagnosis, and type of transplantation procedure.
Design And Methods: In the context of a descriptive, comparative survey design, surviving recipients of single and bilateral-sequential lung transplants (n = 56) were mailed a symptom frequency and distress questionnaire. The response rate was 85.7% (n = 48). The average time since the recipients’ lung transplantations was 1.5 ± 0.7 years.
Results: Recipients of lung transplants reported that several symptoms (eg, muscle weakness, shortness of breath with activity, and changed appearance) were both frequently occurring and quite distressing. Other symptoms were identified as being distressing, but not frequently occurring, or vice versa. Significant (
P < .05) differences were found for symptom experiences among pretransplant diagnostic groups and between genders and types of transplant procedures.
Conclusions: These findings elucidate the symptom experiences of recipients of lung transplants and suggest that subgroup differences exist. The data provide a basis for strengthening patient and family education and for developing symptom management strategies. Further investigation of the symptom experiences of the recipients of lung transplants is needed, especially in relation to subgroups. (Heart Lung® 1999;28:429-37)
Lung transplantation is a growing surgical option for patients with end-stage lung and pulmonary vascular diseases. After completing an extensive evaluation and meeting the selection criteria, ...patients are listed for either single or bilateral-sequential lung transplantation. Immediate postoperative management requires detailed attention to fluid management, monitoring for infection, reperfusion injury, pulmonary hygiene, and pain management. Length of stay depends on the patient's condition before transplant and postoperative complications. Discharge from the hospital can be as early as 7 days after transplantation. Newer immunosuppressive medications offer more options for treating and preventing rejection. Advanced practice nurses, such as coordinators, case managers, nurse practitioners, and clinical nurse specialists, are uniquely positioned to play key roles in coordinating the care of transplant patients across settings and both before and after the transplant procedure. The perioperative needs of lung transplant patients and the impact of this complex procedure on the recipients' and family's quality of life merit further investigation by clinicians and researchers.
