Although many studies have assessed the diagnostic utility of endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) in the context of a specific disease, few studies have ...assessed the overall diagnostic yield, sensitivity, and negative predictive value in patients with isolated mediastinal and hilar lymphadenopathy (IMHL).
We evaluated the performance of EBUS-TBNA for diagnosing IMHL in a population with a high prevalence of concurrent or preexisting non-pulmonary malignancy.
A retrospective chart review of patients who underwent EBUS-TBNA from October 2008 to April 2014 was performed to identify patients with IMHL. Patients with known or suspected primary pulmonary malignancy were excluded. When available, EBUS-TBNA results were cross-referenced with further diagnostic investigation or clinical diagnosis based on follow-up.
EBUS-TBNA was used to sample 765 lymph nodes from 350 patients. One hundred and fourteen (33.3%) patients had a concurrent or preexisting non-pulmonary malignancy. The overall yield of EBUS-TBNA for specific diagnosis was 300/350 (86%). The diagnostic yield for sarcoidosis, lymphoproliferative disease, metastatic lymphadenopathy from extrathoracic malignancy, and necrotizing granuloma was 123/149 (83%), 27/33 (82%), 20/25 (80%), and 13/19 (68%), respectively. Amongst 50 patients with non-diagnostic EBUS-TBNA, 25 yielded an insufficient sample and another 25 yielded only benign lymphoid material which was not representative of the underlying pathology. Overall, EBUS-TBNA had a sensitivity of 89%, a diagnostic yield of 86%, and a negative predictive value of 79%.
For patients with isolated hilar or mediastinal lymphadenopathy and a high background prevalence of concurrent and preexisting non-pulmonary malignancy, EBUS-TBNA is a reliable first-line diagnostic investigation.
An approach which employs pentameric porphyrin arrays as building blocks toward larger porphyrin arrays is described. Two flexible, and one relatively rigid, Ru-centered porphyrin pentamers (1 − 3) ...were synthesized and fully characterized. Their potential as building blocks toward larger porphyrin arrays has been studied via their coordination chemistry using bidentate and tetradentate ligands. DABCO (diazabicyclo2.2.2octane) can bind two monomeric porphyrins but was found to be too small to allow the complete formation of a 10-porphyrin array. On the other hand, titration of a larger bridging dipyridyl porphyrin ligand 17 (0.5 equiv) with 1 or 2 and tetrapyridyl ligand 18 (0.25 equiv) with 3 results in the formation of the 11-porphyrin and 21-porphyrin arrays, respectively, with the 21-porphyrin array containing porphyrins in three different metalation states. Changes in the chemical shift of the inner NH protons as well as the ortho- and meso-protons of the pyridyl groups of the porphyrin ligand clearly indicate the formation of large multiple porphyrin complexes. These studies demonstrate that by use of carefully designed building blocks and suitable bridging ligands, porphyrin arrays can be constructed with a dramatic increase in size in relatively few steps. Exploiting the fact that the strength of binding of pyridyl ligands is Ru > Zn > Ni, intra- vs intermolecular competition has been used to investigate aspects of the folding of the array. The photophysical properties of 3 are also described.
The synthesis of linear multiporphyrin arrays with mono- and bisphosphine-substituted porphyrins as ligand donors and ruthenium(II) or rhodium(III) porphyrins as ligand acceptors is described. With ...appropriate amounts of the building blocks mixed, linear dimeric and trimeric arrays have been synthesized and analyzed by 1H NMR and 31P NMR spectroscopy. The Ru/Rh acceptor porphyrins can be located either at the periphery or in the center of the array. Likewise, the monophosphine porphyrins can be positioned at the periphery, thus allowing a high degree of freedom in the overall composition of the arrays. This way, both donor and acceptor porphyrins can act as chain extenders or terminators. One of the trimeric complexes with two nickel and one ruthenium porphyrin has also been analyzed by X-ray crystallography. Attempts have also been made to synthesize higher order arrays by mixing appropriate amounts of the porphyrins; however, from the NMR data it cannot be concluded if monodisperse five, seven, or nine porphyrin arrays are present or if the solutions are composed of a statistical mixture of smaller and larger arrays.
We have investigated the effect of complexation of different phosphorus ligands on the stability, solid state structure, and spectroscopic properties (NMR, IR, UV−vis) of a 5,15-diphenyl-substituted ...ruthenium porphyrin, (MeOH)RuII(CO)(DPP) 2 DPP = 5,15-bis(3‘,5‘-di-tert-butyl)phenyl-2,8,12,18-tetraethyl-3,7,13,17-tetramethylporphyrin. The ligands used are PPh3, diphenyl(phenylacetenyl)phosphine (DPAP), bis(diphenylphosphino)acetylene (DPPA), tris(phenylacetenyl)phosphine (PA)3P, and diethyl (phenylacetenyl)phosphonite PAP(OEt)2. The mono-phosphine complexes (PR3)RuII(CO)(DPP) are readily formed in solution in quantitative yields. The complexes display association constants ranging from 1.2 × 104 M-1 for PPh3 to 4.8 × 106 M-1 for PAP(OEt)2. The weak association of PPh3 does not correlate with its pK a, δ(31P), or cone angle value and is attributed to steric effects. Due to their kinetic lability, which is shown by 2D NMR spectroscopy, and the weakening of the carbonyl ligand via a trans effect, the mono-phosphine complexes could not be isolated. IR spectroscopy gives the relative order of π-acceptor strength as PPh3 < DPAP, DPPA < (PA)3P < PAP(OEt)2, whereas the relative order of the σ-donor strength is PPh3 < (PA)3P < DPAP, DPPA < PAP(OEt)2, based on the calculated pK a values and on the 31P{1H} NMR chemical shifts of the ligands. The chemical shift differences in the 31P{1H} NMR spectra upon ligand binding display a linear correlation with the calculated pK a values of the protonated ligands HPR3 +; we propose that the pK a, and probably other electronic properties, of a specific phosphorus ligand can be estimated on the basis of the chemical shift difference Δδ(31P) upon complexation to a metalloporphyrin. The bis-phosphine complexes can be isolated in pure form by crystallization from CHCl3−MeOH solutions using excess ligand. Association of the second ligand is in the same order of magnitude as the first binding for the phosphines, but the second phosphonite binding is decreased by a factor of about 100. The solid state structures show only marginal differences in the geometrical parameters. The calculated and the crystallographic cone angles of the ligands generally do not match, apart from the values obtained for PAP(OEt)2.
Fossil fuels will likely remain a major energy source for the foreseeable future, leading to the need for power plants including cost-effective CO2 mitigation systems. Oxygen fired CFB boiler ...technology is an advanced and competitive route to offer in a relative short term commercial units addressing the CO2 capture need.
CFB boilers in operation have shown the ability of this technology to fire a wide range of low-cost fuels. A CO2 capture solution based on CFB technology would, hence, provide the plant with the option to utilize these lower cost fuels and as such is a promising option.
Additionally the route of plant efficiency improvement is of great interest because it leads to CO2 mitigation together with energy sources savings and thus to operational cost reduction. Alstom has a long experience of large supercritical PC boilers and has developed a design of large supercritical CFB boilers.
Oxygen firing can be easily applicable to CFB boilers. The oxygen-fired CFB concept has already been validated in Alstom’s bench- and pilot-scale test facilities.
Next step will involve a demonstration of such technology at a medium scale from 100 MWe.
Asia Energizer Darling, Scott L
J.P. Morgan Equities Research Reports,
07/2020
Report
Energy transition continues to be a structural theme in the Asia energy sector this year and continues to build momentum. Recent examples include PTT's possible investment in Indian renewables, see ...note, and PetroChina's potential strategic shift towards new energy, see note. This transition, in ...
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