Update: An Efficient Synthesis of Poly(ethylene glycol)‐Supported Iron(II) Porphyrin Using a Click Reaction and its Application for the Catalytic Olefination of Aldehydes

The facile synthesis of polyethylene glycol (PEG)‐immobilized iron(II) porphyrin using a copper‐catalyzed azide‐alkyne [3+2] cycloaddition “click” reaction is reported. The prepared complex 5 (PEG‐C₅₁H₃₉FeN₇O) was found to be an efficient catalyst for the selective olefination of aldehydes with ethyl diazoacetate in the presence of triphenylphosphine, and afforded excellent olefin yields with high (E) selectivities. The PEG‐supported catalyst 5 was readily recovered by precipitation and filtration, and was recycled through ten runs without significant activity loss.     

Genetic Analysis of Quantitative Signs of White Lupin (Lupinus albus L.) Genotypes

Genetic variability in the base population plays an important role in crop-breeding program. A comprehensive assessment on the quantitative signs of white lupin genotypes was performed to be included in the selection process. Two limits of the environment were applied, i.e., dense and sparse sowing. Positive true heterosis was established in PI533704×Zuter and PI533704×Lucky801 crosses by using the traits of the weight of nodules and fresh root mass weight at both limits of the environment. In more favorable growing conditions, the number and weight of nodules, as well as fresh aboveground mass weight had greater influence on the inheritance of epistatic gene interactions. In the case of dense sowing, the dominant gene actions for the weight of seeds were found more significant. With a high coefficient of inheritance in both environments, the hybrids of PI533704×Zuter and Lucky801×PI533704 were characterized by number and weight of nodules, Zuter×PI533704 by fresh root and aboveground mass weight, and almost all hybrids by seed weight per plant. The assessment of the initial material makes it highly likely to speed up the process of creating new varieties of white lupin.     

Transcranial Doppler for early identification of potential organ transplant donors

BACKGROUND: Encouraging results in transplant medicine create a growing demand for organ transplant donors. Transcranial Doppler (TCD) has been used by several investigators to assess arrest of the cerebral circulation in brain dead patients. We report on TCD as a monitoring tool for early identification of potential organ transplant donors. DESIGN: A prospective clinical study. SETTING: Intensive care unit (ICU) of a 900-bed community hospital (primary and tertiary care center) in Vienna, Austria. SUBJECTS AND METHODS: All patients with acute intracranial lesions admitted to our intensive care unit underwent TCD examination at least once daily. In patients with Glasgow Coma Scores < 7, TCD waveforms with high resistance profiles unchanged by therapeutic attempts to lower intracranial pressure indicated the need for repeated TCD up to four times a day. TCD waveform abnormality consisting of absent or reversed diastolic flow or small early systolic spikes in at least two intracranial arteries was considered to constitute intracranial circulatory arrest. Brain death was confirmed by clinical criteria, an isoelectric electroencephalography (EEG) or non filling of the intracerebral arteries on arteriography. RESULTS: From January 1994 to July 1996 we identified 11 comatose patients as potential organ transplant donors with typical TCD findings indicating intracranial circulatory arrest. Diagnosis was subarachnoid hemorrhage in 7 and intracerebral hemorrhage in 4 patients. Brain death diagnosis according to the criteria of Austrian law was initiated immediately after the TCD findings suggested intracranial circulatory arrest. Confirmation of brain death was obtained by clinical criteria and either EEG (6 patients) or cerebral angiography (5 patients). CONCLUSION: TCD examinations on a daily routine basis offer a noninvasive monitoring method for early assessment of intracranial circulatory arrest. TCD enables quick identification and further diagnosis of candidates for organ transplant donation.     

Tropical traditional fermented food,a field full of promise. Examples from the Tropical Bioresources and Biotechnology programme and other related French–Vietnamese programmes on fermented food

In tropical countries, traditional fermented foods are usually home‐made products obtained through spontaneous fermentation or backslopping. They are now facing an evolution aiming at responding to quality, safety and mass production issues. This requires acquisition of knowledge on raw materials, microbial ecosystems and fermentation processes. Vietnam is a laboratory for such studies as traditional fermented foods play an important role in the diet of Vietnamese and as these foods are very diverse. Among the most popular are nem chua (sausage reminding Thai Nham), dua muoi (cabbage reminding Kimchi), tom chua (shrimps) and the well‐known nuoc mam. The challenge for these products to enter the industrial era is to reach a level of quality and safety without losing their character. Beside the research for starters to elaborate these products, the world of fermented products is also a world of innovation and the microbial ecosystem of traditional products can also be used for the adaptation of fermented products from other regions, such as wines (from grape or other fruits), for cross‐cultural innovations such as soy‐yogurts, for technology transfer from one fermentation (soy sauce) to another one (fish sauce) and for evolution of traditional products towards higher nutritional qualities such as nem chua nam (replacing part of the sausage meat by mushrooms). Finally, these complex microbial ecosystems are a source of probiotic, antimicrobial compounds and biocatalysts, which can benefit health and improve food processes worldwide. After a presentation of Vietnamese traditional fermented foods, this article aims at illustrating the diverse applications of research on fermented products through examples obtained in past research and in the Tropical Bioresources and Biotechnology project.     

Selectivity analysis in electrochemical reactors. I. Experimental study of an electro-organic reaction coupled with parasitic homogeneous chemical reactions

The electrochemical reduction ofN-nitroso-2-methylindoline toN-amino-2-methylindoline is studied experimentally using a batch stirred-tank electrochemical reactor. The influence of important parameters such as temperature, specific electrode area, hydrodynamics of the electrolyte, and initial reactant concentration are examined to quantify their effect on the overall process selectivity. It is shown that the product yield is very sensitive to these parameters due to the complex chemical reaction sequence coupled with the desired heterogeneous electrochemical reaction.     

Supported titanium–magnesium catalysts with different titanium content: Kinetic peculiarities at ethylene homopolymerization and copolymerization and molecular weight characteristics of polyethylene

The effect of Ti content on the activity of titanium–magnesium catalysts (TMC) and molecular weight distribution (MWD) of polyethylene (PE) produced has been studied. It was found that the activity enhances sharply as Ti content decreases from 0.6 to 0.07 wt %, and shows no significant changes in the Ti content range of 0.6–5.0 wt %. The maximum activity (36 kg PE/mmol Ti × h × bar C₂H₄) was observed for TMC with the lowest Ti content. The catalyst with low titanium content (～ 0.1 wt % of Ti) produced PE with narrower MWD (M_w/M_n = 3.1–3.5) as compared to catalysts with higher titanium content (3–5 wt % of Ti; M_w/M_n = 4.8–5.0). New data on the effect of hydrogen on MWD of PE have been found. Increasing hydrogen concentration results in broadening the MWD of PE, especially in the case of TMC with high titanium content. The data presented indicate the heterogeneity of active centers of TMC in the reaction of chain transfer with hydrogen. The data on the ethylene–hexene‐1 copolymerization over TMC with different titanium content are presented. Comonomer reactivity ratios were shown to be independent of the Ti content in TMC. Presumably the difference in activity of these catalysts is mainly caused by the difference in the number of active centers. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102:5436–5442, 2006     

Computing Conformal Maps of Finitely Connected Domains onto Canonical Slit Domains

We continue the research initiated in Andreev et al. (Computing conformal maps onto circular domains, 2010, submitted) on the computability of conformal mappings of multiply connected domains by showing that the conformal maps of a finitely connected domain onto the canonical slit domains can be computed uniformly from the domain and its boundary. Along the way, we demonstrate the computability of finding analytic extensions of harmonic functions and solutions to Neuman problems. These results on conformal mapping then follow easily from M. Schiffer’s constructions (Dirichlet Principle, Conformal Mapping and Minimal Surfaces, Interscience, New York, 1950).