Recoverable Palladium Catalysts for Suzuki–Miyaura Cross‐ Coupling Reactions Based on Organic‐Inorganic Hybrid Silica Materials Containing Imidazolium and Dihydroimidazolium Salts

The systems formed by palladium acetate [Pd(OAc)₂] and hybrid silica materials prepared by sol‐gel from monosilylated imidazolium and disilylated dihydroimidazolium salts show catalytic activity in Suzuki–Miyaura cross‐couplings with challenging aryl bromides and chlorides. They are very efficient as recoverable catalysts with aryl bromides. Recycling is also possible with aryl chlorides, although with lower conversions. In situ formation of palladium nanoparticles has been observed in recycling experiments.     

Reduced endogenous estrogen delays epididymal development but has no effect on efferent duct morphology in boars

The study presented herein was designed to test the hypothesis that reduced endogenous estrogen in the boar alters efferent duct morphology, epididymal morphology, and steroid receptor expression. Twenty-eight littermate pairs of boars were treated with Letrozole, an aromatase inhibitor, or with vehicle from 1 week of age until castration at 2 through 8 months. Efferent ducts and epididymides were examined for morphological development and steroid receptor expression. Efferent duct morphology was not different between control and Letrozole-treated animals at any examined age. Androgen receptor (AR), estrogen receptor alpha (ERalpha), and beta (ERbeta) were expressed in the epithelial cells of the efferent ducts at all ages; expression was similar in control and treated animals. Morphological development of the caput and corpus was delayed in Letrozole-treated animals, but this delay was transient since morphology was similar between control and treated animals at 8 months. The cauda did not show a delay in development, but was more developed in treated animals at 2 months. AR, ERalpha, and ERbeta were expressed in all three epididymal regions; no difference was observed between control and treated animals. In summary, estrogen appears to be important for development of the epididymis; however, the cauda may be regulated differently than the caput and corpus. Results for the efferent ducts suggest that the normally high endogenous estrogens are not required for regulation of fluid reabsorption in the boar. It also suggests that any ER activation required for maintenance of efferent duct morphology and function is normal in Letrozole-treated boars.     

In vivo copper- and cadmium-binding ability of mammalian metallothionein domain

The ß domain of mouse metallothionein 1 (ßMT) wassynthesized in Escherichia coli cells grown in the presenceof copper or cadmium. Homogenous preparations of Cu–ßMTand Cd–ßMT were used to characterize the correspondingin vivo-conformed metal-clusters, and to compare them with thespecies obtained in vitro by metal replacement to a canonicalZn₃–ßMT structure. The copper-containing ßMTclusters formed inside the cells were very stable. In contrast,the nascent ß peptide, although it showed cadmium bindingability, produced a highly unstable species, whose stoichiometrydepended upon culture conditions. The absence of ßMT proteinin E.coli protease-proficient hosts grown in cadmium-supplementedmedium pointed to drastic proteolysis of a poorly folded ßpeptide, somehow enhanced by the presence of cadmium. Possiblefunctional and evolutionary implications of the bioactivityof mammalian ßMT in the presence of monovalent and divalentmetal ions are discussed.     

Microbial risk and removal--a utility perspective.

In this paper the results of a sampling programme, undertaken as part of the EU MicroRisk project, are described. This project was undertaken to ascertain the occurrence of pathogens and indicators in the River Thames and their subsequent removal through a treatment works. Appropriate physico-chemical surrogates, as determined by statistical correlation are proposed for the microorganisms identified in the raw water. This study shows that under normal raw water conditions the treatment works is able to remove microbial contamination with a significant margin of safety.     

Effluent quality from 200 on-site sewage systems: design values for guidelines.

The quality of effluent from an on-site sewage treatment system is a critical factor in designing the disposal area and, hence, ensuring the sustained performance of the system. Contaminant concentrations in effluent are typically specified in regulatory guidelines or standards; however, the accuracy of these guideline values are brought into question due to the poor performance of septic tanks and the high failure rates of disposal systems reported here and elsewhere. Results from studies of septic tank effluent quality indicated that the effluent is of poorer quality than currently suggested by guidelines. Aerated wastewater treatment systems were found to perform to accreditation guidelines; however, insufficient nutrient data is presently available to assess nutrient loads. It is proposed that the 80th percentile of system performance be adopted as the design value for sizing effluent disposal areas to minimise failure associated with overloading. For septic tanks this equates to 660 mg L(-1) SS, 330 mg L(-1) BOD, 250 mg L(-1) TN and 36 mg L(-1) TP.     

Influence of ripening stage and maceration length on the contribution of grape skins,seeds and stems to phenolic composition and astringency in wine-simulated macerations

This paper studies the influence of ripening stage and maceration time (1–23 days) on the contribution of each cluster grape components to phenolic composition and astringency in wine-simulated macerations. In general terms, proanthocyanidin extraction from skins, stems and especially from seeds increased with maceration time. The ripening stage also had a major influence on tannin extraction and astringency. The tannin contribution from skins and stems increased with ripening but the contribution from the seeds decreased. The contribution to astringency from all cluster components was clearly higher when the grapes were unripened. The mean degree of polymerization of the tannins from skin and seed components was unaffected by ripening and maceration length.     

Attention to Science/Environment News Positively Predicts and Attention to Political News Negatively Predicts Global Warming Risk Perceptions and Policy Support

Contemporary science and environmental news coverage of global warming increasingly portrays scientific consensus. Political news coverage of global warming, however, typically portrays controversy. We hypothesize that attention to science and environmental news is associated with beliefs more consistent with the global warming science and higher risk perceptions, and that the opposite is true of attention to political news. Furthermore, we hypothesize that science‐based beliefs and risk perceptions are positively associated with support for policies aiming at reducing global warming. These hypotheses were confirmed by survey data from a nationally representative sample of adults (N = 2,164). These findings support and extend the cognitive mediation model of news learning and have important practical ramifications.     

Hybrid Organic‐Inorganic Materials Derived from a Monosilylated Hoveyda‐type Ligand as Recyclable Diene and Enyne Metathesis Catalysts

The synthesis of a monosilylated Hoveyda‐type monomer is described as well as the preparation of several organic‐inorganic hybrid materials derived from it by sol‐gel processes and by anchoring to commercial silica gel and MCM‐41. The resulting materials were treated with first and/or second generation Grubbs’ catalyst to generate Hoveyda–Grubbs’ type alkylidene ruthenium complexes covalently bonded to the silica matrix. These materials are efficient recyclable catalysts for the ring‐closing metathesis reaction of dienes and enynes, even for the formation of tri‐ and tetrasubstituted olefins.     

Results and consequences of frequent quality control of quantitative clinical 1H-MR-spectroscopy

BACKGROUND: The cut-off point of serum C-reactive protein to differentiate the mild from the severe form of acute pancreatitis is still debated; data concerning the C-reactive protein pattern in assessing the severity of acute biliary pancreatitis are lacking. AIM: To define the best cut-off point in differentiating the severe from the mild form of acute biliary pancreatitis. PATIENTS: Fifty patients with acute biliary pancreatitis: 34 patients with mild pancreatitis and 16 with the severe form of the disease were studied. METHODS: Serum C-reactive protein concentrations were assessed in all patients upon admission and for the following 5 days. RESULTS: No significant difference in serum C-reactive protein levels was found in the first 2 days in patients with mild pancreatitis compared to those with the severe form of the disease. Using a cut-off point of 11 mg/dl, the sensitivity of serum C-reactive protein in assessing the severity of acute pancreatitis during the first two days of the study was 9% and 57%, the specificity, 93% and 81%, and the accuracy 71% and 74%, respectively. CONCLUSIONS: Serum determination of C-reactive protein in the first 48 hours of the disease is not a reliable marker of the severity of acute biliary pancreatitis.