ABSTRACT
BACKGROUND: Lung transplantation has long been the accepted therapy for end-stage pulmonary fibrotic disease. Presently, there is an ongoing debate over whether single or bilateral transplantation is the most appropriate treatment for end-stage disease, with a paucity of high-quality evidence comparing the two approaches head-to-head. METHODS: This review was performed in accordance with PRISMA recommendations and guidance. Searches were performed on PubMed Central, Scopus and Medline from dates of database inception to September 2019. For the assessed papers, data was extracted from the reviewed text, tables and figures, by two independent authors. Estimated survival was analyzed using the Kaplan-Meier method for studies where time-to-event data was provided. RESULTS: Overall, 4,212 unique records were identified from the literature search. Following initial screening and the addition of reference list findings, 83 full-text articles were assessed for eligibility, of which 17 were included in the final analysis, with a total of 5,601 patients. Kaplan-Meier survival analysis illustrated improved survival in patients receiving bilateral lung transplantation (BLTx) than in those receiving unilateral transplantation for idiopathic pulmonary fibrosis at all time intervals, with aggregated survival for BLTx at 57%, 35.3% and 24% at 5-, 10- and 15-year follow-up, respectively. Survival rates for SLTx were 50%, 27.8% and 13.9%, respectively. CONCLUSIONS: Whilst a number of studies present conflicting results with respect to short-term transplantation outcomes, BLTx confers improved long-term survival over SLTx, with large-scale registries supporting findings from single- and multi-center studies. Through an aggregation of published survival data, this meta-analysis identified improved survival in patients receiving BLTx versus SLTx at all time intervals.
ABSTRACT
Macro-porous tin oxide was prepared as an enhanced sensing material for sulfur compounds, such as hydrogen sulfide. Poly-methyl-methacrylate (PMMA) was used as a template for the formation of macro-pores. Tin chloride was used as a precursor for the synthesis of tin oxide, and was impregnated over PMMA beads using a rotary vacuum evaporator. The solid Sn/PMMA material was treated thermally for 4 h at 600 degrees C. The porous morphology of tin oxide prepared in this study was observed by scanning electron microscopy. The surface area of this material measured by the nitrogen adsorption method was approximately 56 m2/g. The crystal structure of the porous material analyzed by XRD was a typical structure of tin oxide. The response of macro-porous tin oxide as a chemical gas sensor was measured using an I-V source meter and the change in signal was observed with the repeated injection of hydrogen sulfide and air. The sensing tests for macro-porous tin oxide were carried out at 200 degrees C and the fast response of macro-porous sensing material was also confirmed.
Subject(s)
Sulfur Compounds/analysis , Tin Compounds/chemistry , Microscopy, Electron, Scanning , Porosity , X-Ray DiffractionABSTRACT
Macro-porous Al2O3 as the catalytic support material was synthesized using colloidal polystyrene spheres over a micro-channel plate. The colloidal polystyrene spheres were used as a template for the production of an ordered macro porous material using an alumina nitrate solution as the precursor for Al2O3. The close-packed colloidal crystal array template method was applied to the formulation of ordered macro-porous Al2O3 used as a catalytic support material over a micro-channel plate. The solvent in the mixture solution, which also contained the colloidal polystyrene solution, aluminum nitrate solution and the precursor of the catalytic active materials (Rh), was evaporated in a vacuum oven at 50 degrees C. The ordered polystyrene spheres and aluminum salt of the solid state were deposited over a micro channel plate, and macro-porous Al2O3 was formed after calcination at 600 degrees C to remove the polystyrene spheres. The catalytic activity of the Rh/macro-porous alumina supported over the micro-channel plate was tested for diesel reforming.
ABSTRACT
A macro-porous silica layer, consisting of a silica layer with macro-sized pores, was formed as an antireflective material on glass substrates. The silica layer and macro-pores were formed by the oxidative thermal decomposition of tetra-ethylorthorsilicate (TEOS) used as the precursor and polystyrene (PS) spherical beads used as the polymer template for the macro-pores at high temperatures. The size of pores was determined by the size of PS beads in the antireflective agent solution. The size of the PS spherical beads can be controlled by changing the concentration of styrene monomer, and the porosity of the macro pore in the silica layer could be controlled by the TEOS/PS ratio. The optimal thermal treating temperature for the formation of a macro-porous silica layer was found to be 650 degrees C. The size of the spherical type macro pores formed in the silica layer on the glass substrate was 100-150 nm. UV-Vis spectrophotometry confirmed the improved antireflective properties of the glass substrate with the macro-porous silica layer.
