Synergism in the wetting properties of ternary surfactant mixtures

It has been shown that ternary surfactant synergism can be predicted on the basis of nonideality parameters of binary subsystems derived from advancing contact angles. Studies with appropriate surfactant mixtures of glucamides, ether sulfates, secondary alkane sulfonates, and alkylamidopropyl betaines were performed on substrates of different polarity.     

Das Scaling‐Down‐Problem bei der Zweistoff‐Gaszerstäubung von Metallschmelzen

The production capacities of plants for metal pulverisation are frequently rated according to the minimum throughput of melt flowing from the distributor crucible to pulverisation. Especially in the case of high‐melting point metals and their alloys deficiencies occur in the thermal balance of the crucible in the exit section as a result of gas expansion at the pulverisation gas jets, which act as heat sinks. Minimum throughputs and associated limiting values of the convective heat transfer of the melt are stipulated in order to prevent "freezing" (solidification of the melt) in the crucible. The pertinent situation is illustrated for copper and steel melts and technical possibilities for compensating for heat deficiencies by inductive heating of the distributor exit are presented. In addition, the demand for minimum throughputs can be abandoned, and there result possibilities of scaling‐down and energy conservation as well as improvement of powder discharge.     

Integrierter Umweltschutz und Biotechnologie: Ökobilanz und Wirtschaftlichkeitsrechnung im Innovationsprozess

The main objectives of integrated approaches to environmental protection in industrial processes are cost reduction and a reduction of environmental impact. Environmental protection measures should be integrated into the innovation processes since it is during the development stage that some 80% of the overall costs arise. Substantial potential for such innovation exists in the chemical industry, especially in the field of fine chemicals. The substitution of traditional chemical industrial procedures by biotechnological methods appears particularly promising. For example, the use of enzymes (extremozymes) or fermentative methods has much to offer. Estimation of the benefits of such procedures critically depends on information instruments such as eco‐balances in combination with analysis of economic efficiency. Since such instruments are not consistent in their approach and application, further considerations concerning the amalgamation are required.     

Regulation of Epigenetic Modifications in the Placenta during Preeclampsia: PPARγ Influences H3K4me3 and H3K9ac in Extravillous Trophoblast Cells

The aim of this study was to analyze the expression of peroxisome proliferator-activated receptor γ (PPARγ) and retinoid X receptor α (RxRα), a binding heterodimer playing a pivotal role in the successful trophoblast invasion, in the placental tissue of preeclamptic patients. Furthermore, we aimed to characterize a possible interaction between PPARγ and H3K4me3 (trimethylated lysine 4 of the histone H3), respectively H3K9ac (acetylated lysine 9 of the histone H3), to illuminate the role of histone modifications in a defective trophoblast invasion in preeclampsia (PE). Therefore, the expression of PPARγ and RxRα was analyzed in 26 PE and 25 control placentas by immunohistochemical peroxidase staining, as well as the co-expression with H3K4me3 and H3K9ac by double immunofluorescence staining. Further, the effect of a specific PPARγ-agonist (Ciglitazone) and PPARγ-antagonist (T0070907) on the histone modifications H3K9ac and H3K4me3 was analyzed in vitro. In PE placentas, we found a reduced expression of PPARγ and RxRα and a reduced co-expression with H3K4me3 and H3K9ac in the extravillous trophoblast (EVT). Furthermore, with the PPARγ-antagonist treated human villous trophoblast (HVT) cells and primary isolated EVT cells showed higher levels of the histone modification proteins whereas treatment with the PPARγ-agonist reduced respective histone modifications. Our results show that the stimulation of PPARγ-activity leads to a reduction of H3K4me3 and H3K9ac in trophoblast cells, but paradoxically decreases the nuclear PPARγ expression. As the importance of PPARγ, being involved in a successful trophoblast invasion has already been investigated, our results reveal a pathophysiologic connection between PPARγ and the epigenetic modulation via H3K4me3 and H3K9ac in PE.     

Constrained accelerated-feedback control for robot motion

Sensing, modeling, control and manufacturing uncertainties make it generally impossible to guarantee the success of high-precision robot tasks. The paper analyzes the relationships among these uncertainty parameters and derives constraints which govern the success of a new form of control strategy: the constrained accelerated-feedback (CAF) control strategy. The CAF control strategy is suitable for high-level control accommodating the use of multiple sensing modalities, and aims at guaranteeing the success of robot motion in spite of uncertainties.     

Benzeneselenenyl Reagents in Organic Synthesis

An account of the most commonly used reagents for the introduction of the benzeneselenyl (phenyl seleno) group is given. The review focuses on the various methods of its introduction as auxiliary, modifying or protective entity, and its subsequent removal, thereby often promoting other reactions as cyclizations or double bond formation. Less emphasis is laid on reactions of the phenylselenenylated intermediates with the PhSe-group left intact utilizing its stabilizing properties on charged intermediates, on reagents with a modified phenyl group, e.g. chiral derivatives, or on reactions not involving intermediate C Se-bond formation.     

Primary Cilia Structure Is Prolonged in Enteric Neurons of 5xFAD Alzheimer’s Disease Model Mice

Neurodegenerative diseases such as Alzheimer’s disease (AD) have long been acknowledged as mere disorders of the central nervous system (CNS). However, in recent years the gut with its autonomous nervous system and the multitude of microbial commensals has come into focus. Changes in gut properties have been described in patients and animal disease models such as altered enzyme secretion or architecture of the enteric nervous system. The underlying cellular mechanisms have so far only been poorly investigated. An important organelle for integrating potentially toxic signals such as the AD characteristic A-beta peptide is the primary cilium. This microtubule-based signaling organelle regulates numerous cellular processes. Even though the role of primary cilia in a variety of developmental and disease processes has recently been recognized, the contribution of defective ciliary signaling to neurodegenerative diseases such as AD, however, has not been investigated in detail so far. The AD mouse model 5xFAD was used to analyze possible changes in gut functionality by organ bath measurement of peristalsis movement. Subsequently, we cultured primary enteric neurons from mutant mice and wild type littermate controls and assessed for cellular pathomechanisms. Neurite mass was quantified within transwell culturing experiments. Using a combination of different markers for the primary cilium, cilia number and length were determined using fluorescence microscopy. 5xFAD mice showed altered gut anatomy, motility, and neurite mass of enteric neurons. Moreover, primary cilia could be demonstrated on the surface of enteric neurons and exhibited an elongated phenotype in 5xFAD mice. In parallel, we observed reduced β-Catenin expression, a key signaling molecule that regulates Wnt signaling, which is regulated in part via ciliary associated mechanisms. Both results could be recapitulated via in vitro treatments of enteric neurons from wild type mice with A-beta. So far, only a few reports on the probable role of primary cilia in AD can be found. Here, we reveal for the first time an architectural altered phenotype of primary cilia in the enteric nervous system of AD model mice, elicited potentially by neurotoxic A-beta. Potential changes on the sub-organelle level—also in CNS-derived neurons—require further investigations.     

Poly(pent‐1‐ene) Synthesized with the Syndiospecific Catalyst i‐Pr(Cp)(9‐Flu)ZrCl2/MAO

1‐Pentene was polymerized with the syndiospecific catalyst system i‐PrC(Cp)(9‐fluorenyl)ZrCl₂/MAO. The molar mass of the resulting polymers depends strongly on the reaction temperature and decreases from M̄_w = 126 000 at 0°C to M̄_w = 46 000 at 100°C, but is more or less independent of the monomer and the MAO concentration. The influence of reaction temperature and concentrations of MAO and monomer on the type of end‐groups generated during the chain termination, as well as on the type of stereoerror, was investigated. The degree of tacticity was dependent on the polymerization temperature with [rrrr] > 0.99 at 0°C and [rrrr] = 0.75 at 100°C.     

A new planar chiral bipyridine-ligand: pyrid-2-yl[2](1,4)benzeno[2](5,8)quinolino-phane

The synthesis of the new planar chiral heterocyclic nitrogen ligand pyrid-2-yl[2](1,4)benzeno[2](5,8)quinolino-phane ( 1 with [2.2]paracyclophane-skeleton is described. The enantiomeric resolution is achieved by HPLC. The CD-spectra of 1 and of its chiral quinoline precursor are recorded. The enantiomerically pure title compound 1 is used in copper-catalyzed asymmetric cyclopropanation of styrene and in asymmetric iridium-catalyzed transfer-hydrogenation of acetophenone.