Functionalized polymers of intrinsic microporosity for highly energy- intensive gas separations

Membrane-based gas separation is a rapidly emerging technology that has been established in the purification of air and hydrogen streams and is showing an increasingly larger role in natural gas sweetening and vapor/gas separations. One strategy actively pursued to generate polymers with combinations of high permeability and high selectivity is the introduction of microporosity (pores \u3c 20 Å) in the polymer matrix. It has been shown that rigid ladder-type chains comprising fused rings joined by sites of contortion pack inefficiently in the solid state to produce polymers of intrinsic microporosity (PIMs). Recently, a successful integration of monomers contorted by spirobisindane, ethanoanthracene, Tröger’s base and triptycene moieties into polyimide structures has also generated highly permeable intrinsically microporous polyimides (PIM-PIs). Some of these PIM-PIs have shown significantly enhanced performance for O2/N2, H2/N2 and H2/CH4 separations with properties defining the most recent 2015 permeability/selectivity upper bounds. Here, we will discuss several series of novel PIM-PIs and ladder PIMs based on rigid and bicyclic moieties, which are solution processable to form mechanically robust films with high internal surface areas (up to 1100 m2/g). Gas permeation and physisorption data indicate the development of an ultramicroporous structure that is tunable for different gas separation applications. Specific emphasis will be placed on the potential use of hydroxyl- and carboxyl-functionalized PIMs for highly-energy demanding applications for natural gas treatment and olefin/paraffin separation

High Cyclin E Staining Index in Blastemal, Stromal or Epithelial Cells Is Correlated with Tumor Aggressiveness in Patients with Nephroblastoma

PURPOSE: Identifying among nephroblastoma those with a high propensity for distant metastases using cell cycle markers: cyclin E as a regulator of progression through the cell cycle and Ki-67 as a tumor proliferation marker, since both are often deregulated in many human malignancies. METHODOLOGY/PRINCIPAL FINDINGS: A staining index (SI) was obtained by immunohistochemistry using anti-cyclin E and anti-Ki-67 antibodies in paraffin sections of 54 postchemotherapy nephroblastoma including 42 nephroblastoma without metastasis and 12 with metastases. Median cyclin E and Ki-67 SI were 46% and 33% in blastemal cells, 30% and 10% in stromal cells, 37% and 29.5% in epithelial cells. The highest values were found for anaplastic nephroblastoma. A correlation between cyclin E and Ki-67 SI was found for the blastemal component and for the epithelial component. Univariate analysis showed prognostic significance for metastases with cyclin E SI in stromal cells, epithelial cells and blastemal cells (p = 0.03, p = 0.01 and p = 0.002, respectively) as well as with Ki-67 SI in blastema (p<10(-4)). The most striking data were that both cyclin E SI and blastemal Ki-67 SI discriminated between patients with metastases and patients without metastasis among intermediate-risk nephroblastoma. CONCLUSIONS: Our findings show that a high cyclin E SI in all components of nephroblastoma is correlated with tumor aggressiveness and metastases, and that assessment of its expression may have prognostic value in the categorization of nephroblastoma

病院紹介

Purpose: Posterior urethral valves are the most common cause of congenital obstructive uropathy leading to renal failure in childhood. We investigate the influence of bladder dysfunction on renal function impairment. Materials and Methods: We retrospectively reviewed the records of 116 patients with posterior urethral valves. After valve ablation urodynamic studies were performed in all patients. The presence of vesicoureteral reflux (VUR), renal dysplasia, serum creatinine during followup as well as urodynamic abnormalities were recorded. Mean followup was 10.3 years after valve ablation. Results: All patients underwent endoscopic valve ablation and urinary diversion was performed in 32. Renal dysplasia was found in 9 patients. Renal function impairment at the end of followup was present in 35 patients. Urodynamic studies showed poor compliance in 30 boys, detrusor overactivity in 44, and poor compliance and detrusor overactivity in 17. Bilateral VUR was found in 17 boys at the time of diagnosis. Urodynamic studies were normal in 23 (20%) patients, of whom 4 had renal failure. Univariate analysis showed that poor compliance and detrusor overactivity had a significant correlation to renal function impairment in addition to bilateral VUR and renal dysplasia. In a multivariate analysis bilateral VUR was an independent prognostic factor for poor prognosis. Conclusions: Bladder dysfunction may contribute to renal function impairment eventually but normal urodynamic findings do not preclude renal deterioration. It is likely that loss of compliance and detrusor overactivity would actually result in a valve bladder reaching its end point function

The Depiction of China in the Poem “The Roofs are Raised at the Edges …” by Olga Sedakova

В тезисах рассматривается восьмое стихотворение поэтического цикла Ольги Седаковой «Китайское путешествие» «Крыши, поднятые по краям», анализируется особенности изображения пространства, проводятся параллели с техникой древнекитайских живописцев.The paper focuses on the eighth poem “The roofs are raised at the edges” of the poetic cycle “The Chinese Travelogue” by Olga Sedakova. We analyze some features of the landscape and draw parallels between Sedakova’s poem and traditional Chinese paintings

A non-adapted sparse approximation of PDEs with stochastic inputs

We propose a method for the approximation of solutions of PDEs with stochastic coefficients based on the direct, i.e., non-adapted, sampling of solutions. This sampling can be done by using any legacy code for the deterministic problem as a black box. The method converges in probability (with probabilistic error bounds) as a consequence of sparsity and a concentration of measure phenomenon on the empirical correlation between samples. We show that the method is well suited for truly high-dimensional problems (with slow decay in the spectrum)

Parameter Identification in a Probabilistic Setting

Parameter identification problems are formulated in a probabilistic language, where the randomness reflects the uncertainty about the knowledge of the true values. This setting allows conceptually easily to incorporate new information, e.g. through a measurement, by connecting it to Bayes's theorem. The unknown quantity is modelled as a (may be high-dimensional) random variable. Such a description has two constituents, the measurable function and the measure. One group of methods is identified as updating the measure, the other group changes the measurable function. We connect both groups with the relatively recent methods of functional approximation of stochastic problems, and introduce especially in combination with the second group of methods a new procedure which does not need any sampling, hence works completely deterministically. It also seems to be the fastest and more reliable when compared with other methods. We show by example that it also works for highly nonlinear non-smooth problems with non-Gaussian measures.Comment: 29 pages, 16 figure

The synthesis, chain-packing simulation and long-term gas permeability of highly selective spirobifluorene-based polymers of intrinsic microporosity

Membranes composed of Polymers of Intrinsic Microporosity (SBF-PIMs) have potential for commercial gas separation. Here we report a combined simulation and experimental study to investigate the effect on polymer microporosity and gas permeability by placing simple substituents such as methyl, t-butyl and fused benzo groups onto PIMs derived from spirobifluorene (PIM-SBFs). It is shown that methyl or t-butyl substituents both cause a large increase in gas permeabilities with four methyl groups enhancing the concentration of ultramicropores (1.0 nm). Long-term ageing studies (>3.5 years) demonstrate the potential of PIM-SBFs as high-performance membrane materials for gas separations. In particular, the data for the PIM derived from tetramethyl substituted SBF reaches the proposed 2015 Robeson upper bound for O2/N2 and, hence, hold promise for the oxygen or nitrogen enrichment of air. Mixed gas permeation measurements for CO2/CH4 of the aged PIM-SBFs also demonstrate their potential for natural gas or biogas upgrading

Apoptosis and Bax Expression are Increased by Coal Dust in the Polycyclic Aromatic Hydrocarbon-Exposed Lung

BACKGROUND: Miners inhaling respirable coal dust (CD) frequently develop coal workers’ pneumoconiosis, a dust-associated pneumoconiosis characterized by lung inflammation and variable fibrosis. Many coal miners are also exposed to polycyclic aromatic hydrocarbon (PAH) components of diesel engine exhaust and cigarette smoke, which may contribute to lung disease in these workers. Recently, apoptosis was reported to play a critical role in the development of another pneumoconiosis of miners, silicosis. In addition, CD was reported to suppress cytochrome P450 1A1 (CYP1A1) induction by PAHs. METHODS: We investigated the hypothesis that apoptosis plays a critical role in lung injury and down-regulation of CYP1A1 induction in mixed exposures to CD and PAHs. We exposed rats intratracheally to 0.0, 2.5, 10.0, 20.0, or 40.0 mg/rat CD and, 11 days later, to intraperitoneal β-naphthoflavone (BNF), a PAH. In another group of rats exposed to CD and BNF, caspase activity was inhibited by injection of the pan-caspase inhibitor Q-VD-OPH [quinoline-Val-Asp (OMe)-CH(2)-OPH]. RESULTS: In rats exposed to BNF, CD exposure increased alveolar expression of the proapoptotic mediator Bax but decreased CYP1A1 induction relative to BNF exposure alone. Pan-caspase inhibition decreased CD-associated Bax expression and apoptosis but did not restore CYP1A1 activity. Further, CD-induced lung inflammation and alveolar epithelial cell hypertrophy and hyperplasia were not suppressed by caspase inhibition. CONCLUSIONS: Combined BNF and CD exposure increased Bax expression and apoptosis in the lung, but Bax and apoptosis were not the major determinants of early lung injury in this model