Hybrider statischer Nachweis für einen Stahlbeton‐Großsilo – Bausubstanzerhaltung versus Abriss und Neubau

Hybrid structural design of a large reinforced concrete slurry silo. Building preservation versus demolition and new construction. The owner of a building or engineering plant is responsible for the requirement of confidence. He must guard against foreseeable hazardous reasons. The commitment includes both its own operations, as well as the environment. In this case a precautionary clarification of the load of predamaged liquid silos is remarkable because of its complexity, of the chosen solution path and the result.     

Lipochitin Oligosaccharides Immobilized through Oximes in Glycan Microarrays Bind LysM Proteins

Glycan microarrays have emerged as novel tools to study carbohydrate–protein interactions. Here we describe the preparation of a covalent microarray with lipochitin oligosaccharides and its use in studying proteins containing LysM domains. The glycan microarray was assembled from glycoconjugates that were synthesized by using recently developed bifunctional chemoselective aminooxy reagents without the need for transient carbohydrate protecting groups. We describe for the first time the preparation of a covalent microarray with lipochitin oligosaccharides and its use for studying proteins containing LysM domains. Lipochitin oligosaccharides (also referred to as Nod factors) were isolated from bacterial strains or chemoenzymatically synthesized. The glycan microarray also included peptidoglycan‐related compounds, as well as chitin oligosaccharides of different lengths. In total, 30 ligands were treated with the aminooxy linker molecule. The identity of the glycoconjugates was verified by mass spectrometry, and they were then immobilized on the array. The presence of the glycoconjugates on the array surface was confirmed by use of lectins and human sera (IgG binding). The functionality of our array was tested with a bacterial LysM domain‐containing protein, autolysin p60, which is known to act on the bacterial cell wall peptidoglycan. P60 showed specific binding to Nod factors and to chitin oligosaccharides. Increasing affinity was observed with increasing chitin oligomer length.     

Regional and distant metastases in laryngeal and hypopharyngeal sarcomas

OBJECTIVE: To determine risk of failure of the Synthes 4.5-mm cannulated screw system instrumentation in equine bone and to compare its application with the Synthes 4.5-mm standard cortex screw system. STUDY DESIGN: The maximum insertion torque of the cannulated and standard cortex screw systems were compared with the ultimate torsional strengths of the equipment. Pullout strength and ultimate tensile load of cannulated and standard cortex screws were also determined. SAMPLE POPULATION: Paired equine cadaver third metacarpal and third carpal bones. METHODS: Maximum insertion torque and ultimate torsional strengths were determined by using an axial-torsional, servohydraulic materials testing system and a hand-held torquometer. Pullout tests were performed by using a servohydraulic materials testing system. RESULTS: Maximum insertion torque of all cannulated instrumentation was less than ultimate torsional strength at all locations (P < .05). Maximum insertion torques of cannulated taps and screws were greater than for standard taps and screws in the third carpal bone (P < .002). Pullout strength of the cannulated screws was less than the standard cortex screws at all sites (P < .001). Cannulated screws broke before bone failure in all but one bone specimen. CONCLUSIONS: The risk of cannulated instrument or screw failure during insertion into bone is theoretically low. The relatively low pullout strength of the cannulated screws implies that the interfragmentary compression achievable is likely to be less than with standard cortex screws. CLINICAL RELEVANCE: The relatively low pullout strength of the cannulated screw suggests that its risk of failure during fracture repair is greater than with the standard cortex screw.     

Clustering of Y chromosome deletions in subinterval E of interval 6 supports the existence of an oligozoospermia critical region outside the DAZ gene

Y chromosome molecular analysis was performed using the STS-PCR technique in 50 patients with oligozoospermia. Microdeletions of interval 6 of the Y chromosome were detected in seven patients, in six of whom subinterval E was affected. All patients retained the RBM1 and DAZ genes, while in one deletion involved the SPGY gene. The size of the deletion was not apparently related to the severity of the disease. These results suggest the presence of an oligozoospermia critical region on the Y chromosome within subinterval E of interval 6.     

Enantioselective rhodium-catalyzed C-C bond activations

The catalytic activation of carbon-carbon single bonds represents a major challenge in organometallic chemistry. Strained ring substrates occupy in this respect a privileged role as their inherent ring strain facilitates the desired metal insertion. Employing symmetrically substituted tert-cyclobutanols, an enantioselective rhodium(I)-catalyzed beta-carbon elimination creates alkyl-rhodium species bearing all-carbon quaternary stereogenic centers. Downstream reactions enable access to a wide range of synthetically versatile products such as substituted cyclohexenones, lactones and indanols with excellent enantioselectivities of up to 99% ee.     

Shear-induced gelation of associative polyelectrolytes

Copolymer of N,N-dimethylacrylamide (DMA) and acrylic acid (AA) was functionalized with pendant alkyl groups. Their dynamic mechanical properties in aqueous solution were investigated using continuous shear and oscillatory shear. Shear flow showed an abrupt divergence of the viscosity at a critical shear stress (σ_c). Oscillatory shear showed, with increasing applied stress, slight shear thinning followed by strong shear thickening above σ_c. The effect of the polymer concentration and the oscillation frequency (ω) was investigated. The behaviour at all concentrations and frequencies was fully determined by the product of the oscillation frequency and the terminal relaxation time (τ) of the systems at rest. Master curves of the data determined at different concentrations and frequencies were obtained if the reduced shear modulus was plotted versus the reduced applied stress at constant ω.τ. The effect of shear increased with decreasing value of ω.τ. At low frequencies the storage shear modulus crossed the loss modulus with increasing shear. A model is proposed for this phenomenon of shear-induced gelation.     

Synthesis and biological properties of cylindramide derivatives: evidence for calcium-dependent cytotoxicity of tetramic acid lactams

To gain insight into the biological properties of tetramic acid lactam cylindramide 1, the analogues 4 a-d bearing a cyclopentane ring instead of the pentalene unit were prepared by tandem conjugate addition/enolate trapping of cyclopentenone 10; a Sonogashira or Stille coupling, followed by a Julia-Kocienski olefination, macrolactamisation and Lacey-Dieckmann cyclisation were the key steps. The previous NMR structure of cylindramide 1, which was based on NOE and J coupling restraints, could be refined by including residual dipolar coupling data measured for a sample of cylindramide that was aligned in polyacrylonitrile (18 %). Biological screening of cylindramide 1 and its analogues 2-epi-1, 20 and 4 revealed promising antiproliferative activity against several tumour cell lines. It turned out that the activity is strongly correlated to the functionalised pentalene system. The configuration of the cyclopentane ring and an intact tetramic acid lactam with the correct configuration seem to play an equal role in the cytotoxicity. The antiproliferative activity was found to be calcium dependent. Phenotypic characterisation of the mode of action showed vacuolisation and vesicle formation in the endoplasmic reticulum.     

Different Apoptotic Pathways Activated by Oxaliplatin in Primary Astrocytes vs. Colo-Rectal Cancer Cells

Oxaliplatin-based chemotherapy improves the outcomes of metastatic colorectal cancer patients. Its most significant and dose-limiting side effect is the development of a neuropathic syndrome. The mechanism of the neurotoxicity is unclear. The limited knowledge about differences existing between neurotoxic and antitumor effects hinders the discovery of effective and safe adjuvant therapies. In vitro, we suggested cell-specific activation apoptotic pathways in normal nervous cells (astrocytes) vs. colon-cancer cells (HT-29). In the present research we compared the apoptotic signals evoked by oxaliplatin in astrocytes and HT-29 analyzing the intrinsic and extrinsic apoptotic pathways. In astrocytes, oxaliplatin induced a mitochondrial derangement measured as cytosolic release of cytochrome C, increase in superoxide anion levels and decreased expression of the antiapoptotic protein Bcl-2. Caspase-8, a main initiator of the extrinsic process remained unaltered. On the contrary, in HT-29 oxaliplatin increased caspase-8 activity and Bid expression, thus activating the extrinsic apoptosis, while the Bcl-2 increased expression blocked the mitochondrial damage. Data suggest the preferred activation of the intrinsic apoptosis as oxaliplatin damage signaling in normal nervous cells. The extrinsic pathway prevails in tumor cells indicating a possible strategy for planning new molecules to treat oxaliplatin-dependent neurotoxicity without negatively influence chemotherapy.     

Application of dimensionality reduction to visualisation of high-throughput data and building of a classification model in formulated consumer product design

Several dimensionality reduction techniques were applied to two data sets of consumer products formulations in order to infer their intrinsic structure and specific product design rules. High throughput experiments were used to generate the data sets of sufficient size. Supervised isometric feature mapping (S-Isomap) was combined with a k-nearest neighbours (k-NN) classifier and k-means clustering algorithm to perform categorization of viscosity of new formulations, not used to train the model. We compared prediction results of this approach with several well-established classification models. The results show the accuracy of the S-Isomap based approach to be superior and with a potential for further improvement. Compared with other dimensionality reduction techniques, applying S-Isomap has allowed for a superior visualization of category separation within the formulations, for the data sets used.