The exchange of planning ideas from Europe to the USA after the Second World War: introductory thoughts and a call for further research

The transnational exchange of planning ideas after the Second World War was multi-directional. As this special issue demonstrates, while American concepts spread globally there was also a steady transfer of European ideas to the USA. European émigrés in the USA and American professionals explored the reconstruction of European downtowns, particularly in Northern Europe. This special issue builds on a growing interest in transnational planning history, including a desire to develop research and writing methods. The current issue contains an overview of secondary literature (Wakeman), a careful investigation of post-war professional transatlantic dialogue (Joch), research on the International Federation for Housing and Planning conference held in The Hague in 1958 (Wagner), and an examination of the term and concept of urban design throughout the Anglophone world (Orillard). The introduction also proposes further directions for research that consciously engages with changing global contexts, and studies their impact on planning beyond physical, theoretical, temporal or other boundaries, for example, discussing planners and plans that crossed the schism of the Cold War. It also calls for global integration of research tools and collaboration among researchers in the field.     

Novel nano-composite biomimetic biomaterial allows chondrogenic and osteogenic differentiation of bone marrow concentrate derived cells

In clinical orthopedics suitable materials that induce and restore biological functions together with the right mechanical properties are particularly needed for the regeneration of osteochondral lesions. For this purpose, the ideal scaffold should possess the right properties with respect to degradation, cell binding, cellular uptake, non-immunogenicity, mechanical strength, and flexibility. In addition, it should be easy to handle and serve as a template for chondrocyte and bone cells guiding both cartilage and bone formation. The aim of the present study was to estimate the chondrogenic and osteogenic capability of bone marrow concentrated derived cells seeded onto a novel nano-composite biomimetic material. These properties have been evaluated by means of histological, immunohistochemical and electron microscopy analyses. The data obtained demonstrated that freshly harvested cells obtained from bone marrow were able, once seeded onto the biomaterial, to differentiate either down the chondrogenic and osteogenic pathways as evaluated by the expression and production of specific matrix molecules. These findings support the use, for the repair of osteochondral lesions, of this new nano-composite biomimetic material together with bone marrow derived cells in a “one step” transplantation procedure.     

Simple and optimal randomized fault-tolerant rumor spreading

We revisit the classic problem of spreading a piece of information in a group of \(n\) fully connected processors. By suitably adding a small dose of randomness to the protocol of Gasieniec and Pelc (Parallel Comput 22:903–912, 1996), we derive for the first time protocols that (i) use a linear number of messages, (ii) are correct even when an arbitrary number of adversarially chosen processors does not participate in the process, and (iii) with high probability have the asymptotically optimal runtime of \(O(\log n)\) when at least an arbitrarily small constant fraction of the processors are working. In addition, our protocols do not require that the system is synchronized nor that all processors are simultaneously woken up at time zero, they are fully based on push-operations, and they do not need an a priori estimate on the number of failed nodes. Our protocols thus overcome the typical disadvantages of the two known approaches, algorithms based on random gossip (typically needing a large number of messages due to their unorganized nature) and algorithms based on fair workload splitting (which are either not time-efficient or require intricate preprocessing steps plus synchronization).     

Ranking-Based Black-Box Complexity

Randomized search heuristics such as evolutionary algorithms, simulated annealing, and ant colony optimization are a broadly used class of general-purpose algorithms. Analyzing them via classical methods of theoretical computer science is a growing field. While several strong runtime analysis results have appeared in the last 20 years, a powerful complexity theory for such algorithms is yet to be developed. We enrich the existing notions of black-box complexity by the additional restriction that not the actual objective values, but only the relative quality of the previously evaluated solutions may be taken into account by the black-box algorithm. Many randomized search heuristics belong to this class of algorithms. We show that the new ranking-based model can give more realistic complexity estimates. The class of all binary-value functions has a black-box complexity of O(logn) in the previous black-box models, but has a ranking-based complexity of Θ(n). On the other hand, for the class of all OneMax functions, we present a ranking-based black-box algorithm that has a runtime of Θ(n/logn), which shows that the OneMax problem does not become harder with the additional ranking-basedness restriction.     

Cell wall fermentation kinetics are impacted more by lignin content and ferulate cross‐linking than by lignin composition

BACKGROUND: We used a biomimetic model system to ascertain how reductions in ferulate–lignin cross‐linking and shifts in lignin composition influence ruminal cell wall fermentation. Primary walls from maize cell suspensions with normal or reduced feruloylation were artificially lignified with various monolignols previously identified in normal, mutant, and transgenic plants. Cell wall fermentability was determined from gas production during in vitro incubation with rumen microflora and by analysis of non‐fermented polysaccharides. RESULTS: Hemicellulose fermentation lag time increased by 37%, rate decreased by 37%, and the extent declined by 18% as cell wall lignin content increased from 0.5 to 124 mg g^?1. Lignification increased lag time for cellulose fermentation by 12‐fold. Ferulate–lignin cross‐linking accounted for at least one‐half of the inhibitory effect of lignin on cell wall fermentation. Incorporating sinapyl p‐coumarate, a precursor of p‐coumaroylated grass lignin, increased the extent of hemicellulose fermentation by 5%. Polymerizing varying ratios of coniferyl and sinapyl alcohols or incorporating 5‐hydroxyconiferyl alcohol, coniferaldehyde, sinapyl acetate, or dihydroconiferyl alcohol into lignin did not alter the kinetics of cell wall fermentation. CONCLUSION: The results indicate that selection or engineering of plants for reduced lignification or ferulate–lignin cross‐linking will improve fiber fermentability more than current approaches for shifting lignin composition. Copyright © 2008 Society of Chemical Industry     

Cure kinetics and physical characterization of epoxy/modified boehmite nanocomposites

Nanocomposites based on a cross-linked epoxy matrix with the addition of a reinforcing organically modified boehmite nano-phase were realized and characterized with the aim to produce systems possessing enhanced properties over commercial epoxy systems. Different amounts of a commercially available organically modified boehmite were added to a diglycidyl ether of bisphenol A (DGEBA) epoxy matrix. The rheological characteristic and kinetic behavior of the liquid nano-filled mixtures were analyzed and compared to those displayed by the un-filled resin. A mathematical model was applied to the experimental rheological data in order to assess the aspect ratio of the nano-filler. A proper equation was employed to model the cure kinetics of the nano-filled epoxy systems. The nanocomposites were heat-cured in the presence of an aromatic amine hardener. They were, then, characterized by scanning electron microscopy with EDS analysis, dynamic mechanical thermal analysis, differential scanning calorimetry, and Flexural and Hardness tests. Significant increase in the glass transition temperature, Shore D hardness and maximum flexural strength was found. The experimental results demonstrated the effectiveness of the o-boehmite nano-filler to improve the physical and mechanical properties of the epoxy resin. Further studies are in progress to verify the protective efficiency of the epoxy-boehmite nanocomposite when applied on different substrates as adhesive or coating for construction materials, such as porous stones, concrete, wood, and metal.     

Antimicrobial and Antioxidant Potentials of Essential Oil and Acetone Extract of Myristica fragrans Houtt. (Aril Part)

ABSTRACT: The antifungal, antibacterial, and antioxidant potentials of essential oil and acetone extract were carried out by different techniques. In poison food medium method, the essential oil showed complete zones of inhibition against Fusarium graminearum at the all tested doses. For other tested fungi and bacteria, they gave good to moderate zone inhibition. The antioxidant activity was evaluated by measuring peroxide, thiobarbituric acid and total carbonyl values of rapeseed oil at fixed time intervals. Both the extract and essential oil showed strong antioxidant activity in comparison with butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT). In addition, their inhibitory action in linoleic acid system was studied by monitoring peroxide concentration in emulsion during incubation. The results were well correlated with above values. Their radical scavenging capacity was carried out on 2,2'-diphenyl-1-picrylhydracyl (DPPH) radicalm, and they showed strong scavenging activity in comparison with synthetic antioxidants. Their reducing power was also determined, which also proved strong antioxidant capacity of essential oil and extract. Gas chromatographic-mass spectroscopy studies on essential oil resulted in the identification of 49 components representing 96.49% of the total amount, and the major component was sabinene (20.22%), followed by terpinen-4-ol (12.08%), safrole (10.32%), αpinene (9.7%), β-phellandrene (6.56%), and γ-terpinene (5.93%). The acetone extract showed the presence of 23 components representing 71.66% of the total amount. The major components were isocroweacin (18.92%), elemicin (17.68%), methoxyeugenol (8.13%), linoleic acid (4.12%), dehydrodiisoeugenol (4.06%), palmitic acid (2.8%), and trans-isoeugenol (2.76%).     

Occurrence and spread of antibiotic resistances in Enterococcus faecium

Enterococci are the second to third most important bacterial genus in hospital infections. Especially Enterococcus (E.) faecium possesses a broad spectrum of natural and acquired antibiotic resistances which are presented in detail in this paper. From medical point of view, the transferable resistances to glycopeptides (e.g., vancomycin, VAN, or teicoplanin, TPL) and streptogramins (e.g., quinupristin/dalfopristin, Q/D) in enterococci are of special interest. The VanA type of enterococcal glycopeptide resistance is the most important one (VAN-r, TPL-r); its main reservoir is E. faecium. Glycopeptide-resistant E. faecium (GREF) can be found in hospitals and outside of them, namely in European commercial animal husbandry in which the glycopeptide avoparcin (AVO) was used as growth promoter in the past. There are identical types of the vanA gene clusters in enterococci from different ecological origins (faecal samples of animals, animal feed, patients in hospitals, persons in the community, waste water samples). Obviously, across the food chain (by GREF-contaminated meat products), these multiple-resistant bacteria or their vanA gene clusters can reach humans. In hospital infections, widespread epidemic-virulent E. faecium isolates of the same clone with or without glycopeptide resistance can occur; these strains often harbour different plasmids and the esp gene. This indicates that hospital-adapted epidemic-virulent E. faecium strains have picked up the vanA gene cluster after they were already widely spread. The streptogramin virginiamycin was also used as feed additive in commercial animal husbandry in Europe for more than 20 years, and it created reservoirs for streptogramin-resistant E. faecium (SREF). In 1998/1999, SREF could be isolated in Germany from waste water of sewage treatment plants, from faecal samples and meat products of animals that were fed virginiamycin (cross resistance to Q/D), from stools of humans in the community, and from clinical samples. These isolations of SREF occurred in a time before the streptogramin combination Q/D was introduced for therapeutic purposes in German hospitals in May 2000, while other streptogramins were not used in German clinics. This seems to indicate that the origin of these SREF or their streptogramin resistance gene(s) originated from other sources outside the hospitals, probably from commercial animal husbandry. In order to prevent the dissemination of multiple antibiotic-resistant enterococci or their transferable resistance genes, a prudent use of antibiotics is necessary in human and veterinary medicine, and in animal husbandry.     

On the temperature dependence of the resistive and surface ionisation response of SnO2 gas sensing layers

Gas sensing experiments have been performed on SnO₂ thin films using a wide range of different analyte gases. In these experiments, the SnO₂ layers were specifically configured to observe the familiar resistive (RES) gas response alongside with the novel surface ionisation (SI) response. It is shown that the RES and SI responses, in general, occur in dissimilar temperature ranges and that both follow very different selectivity criteria. Microscopically, both kinds of response proceed through analyte-specific sequences of adsorption, surface reaction, charge transfer and desorption steps. A generalisation of the Ahlers model [1], originally developed to account for the bell-shaped temperature variation of the RES response of thin film metal oxide layers, is shown to quantitatively account for the whole range of SI data. Fits to experimental SI response vs. temperature curves allow the total energy input into the surface ionisation process to be determined and insights into the ionisation mechanism to be gained.     

Le Kambary酒店

建筑材料包括石头、泥土和砖块。跟建筑师以前的项目一样,他希望不使用稀缺且造价较高的建筑材料木材来完成建筑。石质的园顶和拱门就成为主要的建筑施工部分。这些如同巨大的蜂房一样的圆顶建筑矗立在沙漠中。