Polyamido amine (PAMAM)-grafted magnetic nanotubes as emerging platforms for the delivery and sustained release of silibinin

This work reports the synthesis of surface-modified iron oxide magnetic nanotubes (Fe₃O₄NT) with poly(amido amine) dendrimers of the third generation (PAMAM-G3) as novel nanomaterials for potential drug-delivery applications. Fe₃O₄NT were obtained by reduction of α-Fe₂O₃ nanotubes, which were synthesized following a hydrothermal strategy using SO₄ ^2?/H₂PO₄ ^? to control the size and morphology of the prepared materials. Fe₃O₄NT were further functionalized with PAMAM-G3 moieties using a silane coupling agent. Pristine and PAMAM-modified Fe₃O₄NT were characterized through TEM, FTIR, XRD, N₂ adsorption–desorption isotherms and VSM measurements, which confirmed the nanotubular morphology and magnetic behavior for both systems, and TGA analyses, which revealed a PAMAM grafting percentage of 16.8%. The effect of PAMAM conjugation on the adsorption and release properties of Fe₃O₄NT was examined using silibinin as model poorly soluble drug compound. Our results revealed that PAMAM grafting increased the maximum amount of adsorbed drug from 675 mg g^?1 in pristine Fe₃O₄NT to 825 mg g^?1 in PAMAM-Fe₃O₄NT. These quantities exceed by far the drug-loading capacity of other pristine and PAMAM-modified nanotubular systems, which constitutes a relevant outcome for the present study.     

Maurice Rotival: French planning on a world-scale (Part II)

This paper analyses the life and work of the French planner Maurice Rotival through his practical and theoretical work as well as his teachings in cities and regions in Europe, Africa and the Americas. Rotival's plans and projects reflect the influence of major events and changes of the twentieth century - two world wars and the advances in technology and research they promoted, the advent of the automobile, the subsequent urban transformations and large-scale demolitions - and influenced the development of planning in the twentieth century. Through five major steps of Rotival's international career, this article analyses the development of Rotival's pragmatic organic planning doctrine and his regional approach from his experience and training in France at the eve of the First World War, to his subsequent regional and urban planning work in Caracas, New Haven, Europe, Reims and other French cities until the 1980s. By considering Rotival's career as a part of economic globalization at a time when the colonial context was dismantled, the present article highlights the planner's role in societal transformation in collaboration with the e´lite and demonstrates the growing international exchange of planning ideas in the twentieth century.     

Mechanical alloying and subsequent heat treatment of Ag–Zn powders

Microstructural evolution during mechanical alloying of Ag and Zn, and subsequent heat treatments were investigated. The mechanical alloying was carried out in a SPEX 8000D miller. The microstructural characterization was obtained by X-ray diffraction (XRD), transmission electron microscopy (TEM) and scanning electron microscopy (SEM). The thermal behavior was studied using differential scanning calorimetry (DSC). Based on the results obtained, it can be concluded that at the early stages of milling was possible to detect the ?, β, β′, α solid solutions and remaining Zn. Later, the ?, β, β′ and Zn phases disappeared while the Zn concentration of the α solid solution was strongly increased. After 7.2 ks of milling, the mechanical alloying process reached a steady state. During this period, both the composition and crystallite size of the α solid solution remained practically unchanged. On the other hand, subsequent heat treatments of milled powders showed that the α solid solution could also be obtained by the combination of mechanical alloying and heat treatment. Finally, the evolution of the microstructure during milling and annealing was combined to propose an optimal processing route in order to obtain a α solid solution.     

Chemical Composition and Antioxidant Activity of Essential Oil and Oleoresins of Nutmeg (Myristica fragrans Houtt.) Fruits

Essential oil and oleoresins (ethanol, ethyl acetate, and iso-propyl alcohol) of Myristica fragrans were extracted by using Clevenger and Soxhlet apparatus, respectively. Gas chromatography-mass spectrometry analysis of essential oil showed the presence of 38 components representing about 99.6% of the total weight. Sabinene (29.4%) was found to be a major component along with beta pinene (10.6%), alpha pinene (10.1%), terpene-4-ol (9.6%), and several other minor components. The major component of all oleoresins contained elemicin. It has been observed that the essential oil and ethanol oleoresin showed better activity compared to other tested oleoresins and synthetic antioxidants, butylated hydroxyl anisole and butylated hydroxyl toluene. Furthermore, the activity of essential oil and oleoresins was measured for the inhibition of primary and secondary oxidation products in mustard oil by using peroxide, thiobarbituric acid, and p-anisidine values. In addition, these experiments were further supported by other complementary antioxidant assays, such as ferric thiocyanate method in a linoleic acid system, reducing power, chelating effect, and scavenging effects on 1,1′-diphenyl-2-picrylhydrazyl radical. Hence, the essential oil and ethanol oleoresin of M. fragrans could be considered as a natural food preservative.     

Assessment of the relevance of sintering in thermoplastic commingled yarn consolidation

The aim of the present article is to study the different phenomena which are at the basis of the consolidation of commingled thermoplastic semi‐pregs made of amorphous polyester fibers and E‐glass reinforcement. The evolution of the void fraction during the consolidation of the composite was monitored by a dynamometer, equipped with parallel plates and a forced convection oven. Different physical changes were associated to the consolidation temperature. Scanning electron microscopy (SEM) and thermomecahnical analysis (TMA) showed that at low temperature, matrix fiber deformation and sintering are responsible of the initial void reduction. At a temperature higher than the onset of the flow region, reinforcement impregnation is responsible of the further void reduction. Dimensionless analysis confirmed that at lower temperatures, corresponding to higher viscosities, consolidation due to viscous flow of the polymer matrix is negligible compared to consolidation due to sintering of matrix fibers. The results indicate that the Darcy law can efficiently represent the consolidation during the microscale impregnation of the reinforcement, but cannot account for the initial stages of consolidation. POLYM. COMPOS., 2011. © 2011 Society of Plastics Engineers     

Designing Multitarget Anti-inflammatory Agents: Chemical Modulation of the Lumiracoxib Structure toward Dual Thromboxane Antagonists-COX-2 Inhibitors

A series of lumiracoxib derivatives were designed to explore the influence of isosteric substitution on balancing COX-2 inhibition and thromboxane A(2) prostanoid (TP) receptor antagonism. The compounds were synthesized through a copper-catalyzed coupling procedure and characterized for their pK(a) values. TP receptor antagonism was assessed on human platelets; COX-2 inhibition was determined on human isolated monocytes and human whole blood. TPα receptor binding of the most promising compounds was evaluated through radioligand binding assays. Some of the isosteric substitutions at the carboxylic acid group afforded compounds with improved TP receptor antagonism; of these, a tetrazole derivative retained good COX-2 inhibitory activity and selectivity. The identification of this tetrazole acting as a balanced dual-acting compound in human whole blood, along with SAR analysis of the synthesized lumiracoxib derivatives, might contribute to the rational design of a new class of cardioprotective anti-inflammatory agents.     

Effects of roasting and boiling of quinoa,kiwicha and kañiwa on composition and availability of minerals in vitro

BACKGOUND: Andean indigenous crops such as quinoa (Chenopodium quinoa), kiwicha (Amaranthus caudatus) and kañiwa (Chenopodium pallidicaule) seeds are good sources of minerals (calcium and iron). Little is known, however, about mineral bioavailability in these grains. Thus the aim of the present study was to determine the iron, calcium and zinc potential availability in raw, roasted and boiled quinoa, kañiwa and kiwicha seeds. Potential availability was estimated by dialyzability. RESULTS: These seeds are good sources of phenolic compounds and kañiwa of dietary fiber. Their calcium, zinc and iron content is higher than in common cereals. In general, roasting did not significantly affect mineral dialyzability. Conversely, in boiled grains there was an increase in dialyzability of zinc and, in the case of kañiwa, also in iron and calcium dialyzability. CONCLUSION: Taking into account the high content of minerals in Andean grains, the potential contribution of these minerals would not differ considerably from that of wheat flour. Further studies are required to research the effect of extrusion on mineral availability in Andean grains. Copyright © 2010 Society of Chemical Industry     

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.