Sustained-release of Cyclosporin A pellets: preparation,in vitro release,pharmacokinetic studies and in vitro–in vivo correlation in beagle dogs

The aim of this study was to develop Cyclosporin A (CsA) sustained-release pellets which could maintain CsA blood concentration within the therapeutic window throughout dosing interval and to investigate the in vitro–in vivo correlation (IVIVC) in beagle dogs. The CsA sustained-release pellets (CsA pellets) were prepared by a double coating method and characterized in vitro as well as in vivo. Consequently, the CsA pellets obtained were spherical in shape, with a desirable drug loading (7.18?±?0.17?g/100?g), good stability and showed a sustained-release effect. The C_max, T_max and AUC_0–24 of CsA pellets from the in vivo pharmacokinetics evaluation was 268.22?±?15.99?ng/ml, 6?±?0?h and 3205.00?±?149.55?ng·h/ml, respectively. Compared with Neoral®, CsA pellets significantly prolonged the duration of action, reduced the peak blood concentration and could maintain a relatively high concentration level till 24?h. The relative bioavailability of CsA pellets was 125.68?±?5.37% that of Neoral®. Moreover, there was a good correlation between the in vitro dissolution and in vivo absorption of the pellets. In conclusion, CsA pellets which could ensure a constant systemic blood concentration within the therapeutic window for 24?h were prepared successfully. Meanwhile, this formulation possessed a good IVIVC.     

Fluid–solid transition in unsteady,homogeneous, granular shear flows

Discrete element numerical simulations of unsteady, homogeneous flows have been performed by shearing a fixed volume of identical, soft, frictional spheres. A constant, global, shear rate was instantly applied to particles that are initially at rest, non interacting, and randomly distributed. The granular material exhibits either large or small fluctuations in the evolving pressure, depending whether the average number of contacts per particle (coordination number) is less or larger than a critical value. When the coordination number is less than the critical value, the amplitude of the pressure fluctuations is dependent on the shear rate, whereas, it is rate-independent in the opposite case, signatures, according to the case, of fluid-like and solid-like behaviour. The same critical coordination number has been previously found to represent the minimum value at which rate-independent components of stresses develop in steady, simple shearing and the jamming transition in isotropic random packings. The observed complex behaviour of the measured pressure in the fluid–solid transition can be predicted with a constitutive model involving the coordination number, the particle stiffness and the intensity of particle agitation.     

Fatigue damage in aircraft structures,not wanted,but tolerated?

It has been a long way to arrive at the present state of the art about fatigue of structures and materials. Aircraft accidents and incidents were milestones. New concepts were proposed related to structural design, material selection, production techniques, inspection procedures and load spectra. Extensive research efforts have been spent. Our understanding of fatigue damage problems increased significantly. Simultaneously our tools to tackle problems have been developed to a high potential efficiency. And still, there are problems. The present paper is a personal impression of evaluating experience, design aspects, predictions and experiments associated with damage tolerance of aircraft structures.     

Hot Photo–Carriers, Excitons, Desorption, and Surface Diffusion in Rare Gas Solids

The dynamics of valence excitations of rare gas solids were studied with time–and spectrally resolved luminescence experiments. From the decay curves of the free–exciton luminescence in solid X _e , information concerning exciton transport and electron–hole recombination was deduced. The peculiar role of excitons stimulating the luminescence of surface centers and of desorption phenomena was analysed in a simple model system (Kr doped solid Ar). From a time–resolved analysis of the luminescence of surface centers, thermally activated lateral diffusion of Kr* metastables on the surface of the Ar host was established.     

Orbital Degeneracy, Jahn–Teller Effect, and Superconductivity in Transition-Metal Chalcogenides

We have studied the electronic structure of FeSe_1?x Te _x and Ir_1?x Pt _x Te₂ using photoemission spectroscopy. For FeSe_1?x Te _x , angle-resolved photoemission results indicate that the Fe 3d yz/zx orbital degeneracy at ?? point and orbitally induced Peierls effect in the tetragonal lattice play important roles for the superconductivity. It is suggested that the Jahn-Teller instability of the yz/zx states couples with local lattice distortion derived from the Te substitution for Se and provides an inhomogeneous electronic state. Photoemission results of IrTe₂ with triangular lattice are also consistent with the orbitally induced Peierls scenario. The Pt substitution for Ir suppresses the static band Jahn?CTeller effect and induces an inhomogeneous electronic state in which orbital (or bond or nematic) fluctuations may help superconductivity through the Peierls effect.     

Recent advancement in metal–organic framework: synthesis,activation, functionalisation,and bulk production

Metal–organic framework (MOF) is an emerging hybrid material that possesses high surface area, narrow pore size distribution, and tuneable functionality. In recent years, MOF-based materials have been widely studied in various applications such as gas storage, gas separation, heterogeneous catalysis, and drug delivery. However, less emphasis has been placed on the fundamentals of MOF that are crucial to provide scientific knowledge for tailoring MOFs with desirable properties for commercial applications. This review discusses recent advancement in the MOF chemistry, in particular, synthesis, activation, functionalisation, and bulk production of MOFs. This review will be of great interest to the researchers and chemists actively involved in the field of MOFs production.

Abbreviations: BBR: Building block replacement; BDC: 1,4-benzenedicarboxylate; BET: Brunauer–Emmett–Teller; BTC: 1,3,5-benzenetricarboxylate; B_oc: Tert-butoxycarbonyl; Bpy: 4,4’-bipyridine; CFG: Carboxylic functional group; CTAB: Cetyltrimethylammoniumbromide; DABCO: 1,4-diazabicyclo[2.2.2]octane; DEF: N,N-diethylformamide; DMF: N,N-dimethylformamide; Dhybdc: 2,5-dihydroxy-1,4-benzenedicarboxylate; [EMIm]Br: 1-ethyl-3-methylimidazolium bromide; FIR: Fujian Institute of Research; H₂BDC: 1,4-benzenedicarboxylic acid; H₃BTC: 1,3,5-benzenetricarboxylic acid; H₄TBAPy: 1,3,6,8-tetrakis(p-benzoic acid)pyrene; HKUST: Hong-Kong University of Science and Technology; ICP-MS: Inductively coupled plasma mass spectrometry; ILAG: Ion- and liquid-assisted grinding; Im: Imidazole ; IPA: Isophthalate; IRMOF: Isoreticular metal–organic framework; IUPAC: International Union of Pure and Applied Chemistry; LAG: Liquid-assisted grinding; LBL: Layer-by-layer; LIB: Lithium-ion battery; mesoMOF: Mesoporous metal–organic framework; MeIm: 2-methyimidazole; MIL: Matériaux de l’Institut Lavoisier; MixMOF: Mixed-linker metal–organic framework; MOF: Metal–organic framework; MTBS: Methyltributylammoniummethylsulfate; NH₂BTC: 2-aminobenzene-1,3,5-tricarboxylate; NOTT: University of Nottingham; NU: Northwestern University ; PCD: Protection-complexation-deprotection; PCN: Porous coordination network; PCP: Porous coordination polymer; PIM: Polymer of intrinsic microporosity; PSD: Post-synthetic deprotection; PSM: Post-synthetic modification; PXRD: Powder X-ray diffraction; PyCHO: 2-pyridinecarboxaldehyde; RH: Relative humidity; SALE: Solvent-assisted linker exchange; SALI: Solvent-assisted ligand incorporation; scCO₂: Supercritical carbon dioxide; STEM: Scanning transmission electron microscopy; STY: Space–time yield; TBHP: tert-butyl hydroperoxide; TMU: Tarbiat Modares University; UiO: Universitetet i Oslo; ZIF: Zeolitic imidazolate framework     

Specific heat,pressure, and the Grüneisen relation in solid hydrogen

We report systematic measurements ofC _v and (P/T) _v in solid hydrogen below 1 K and for orthohydrogen molar concentrations 0.58X _ortho0.20. This is the temperature and concentration range associated with a proposed quadrupolar glass phase. The results show no overtly glassy properties such as remanence or hysteresis upon warming and cooling, and there is no evidence of anomalous thermal relaxations. We have calculated the quadrupolar Grüneisen constant from our data and find that is only a slowly varying function of temperature and orthohydrogen concentration. TheC _v results are compared with theoretical models and the behavior of a corresponding classical solid, N₂-argon. There are several similarities between the N₂-argon and H₂ behaviors, but the semiempirical single-particle model does not correspond well with the experimental results.     

Productivity ratings of institutions based on publication in Scientometrics,Informetrics, and Bibliometrics, 1981–2000

The author surveyed a set of ten scholarly journals that publish the mainstream of papers in the field of Scientometrics, Informetrics, and Bibliometrics (SIB). The survey is limited only to the research articles published in the field for the two decades period 1981–2000. Each journal was examined issue by issue for the institutional affiliations of contributing authors. Institutional rankings for the total period and the two decade periods; 1981–1990 and 1991–2000 were determined by awarding credit to the authors" institutions based on authorship. In the composite of ten journals, the University Sheffield (England), the University of North Carolina (USA), the University of Leiden (Netherlands), the City University of London (England), the National Institute of Science, Technology and Development Studies (India), the University of Sussex (England), the University of Illinois (USA), the University of Michigan (USA), the Hungarian Academy of Sciences Library (Hungary), and Indiana University (USA) emerged as the ten most productive institutions for the period 1981–2000. This revised version was published online in June 2006 with corrections to the Cover Date.     

Die in sich gedrehte,sich in sich selbst verbiegende Welle und ihre Stabilität

Zusammenfassung Im Gegensatz zur elastisch verbogenen, ursprünglich geraden Welle ist zum Drehen der im spannungslosen Zustand gekrümmten Welle ein mit dem Drehwinkel periodisch ver?nderliches Drehmoment n?tig. Dieses kommt, z. B. bei freier überbrückung des Lagerabstands, durch die Rürckwirkung der w?hrend des Drehens in der Welle vor sich gehenden Verbiegung auf die Lager zustande. Unter der Voraussetzung, daβ die Wellenmittellinie eine ebene, zur Wellenmitte symmetrische und flache Kurve ist, gelingt es verh?ltnism?βig leicht, die auftretenden Kr?fte und Momente zu berechnen. Die periodische Ver?nderlichkeit des Drehmoments mit dem Drehwinkel bedingt das Auftreten einer neuartigen Ausweicherscheinung, die für die Praxis nutzbar gemacht werden kann. L. F?ppl zum 70. Geburtstag gewidmet. VDI     

Fabrication of large-core, high-Δ optical waveguides in polymers

The realization of polymer optical waveguides that have a large core size and high refractive-index difference (LCHD) Δ transmission characteristics is presented. A fabrication procedure for the waveguide based on vertical dip coating and reactive ion etching has been studied. To achieve the lower propagation loss, this procedure includes two original techniques, i.e., the lamination of thick polymer films and sidewall flattening. With these techniques, Δ of 5.4% and a 80 μm × 83 μm core polymer waveguide with 1.4-dB/cm propagation loss were achieved at 680 nm. The LCHD polymer waveguides are useful for practical power-transmission devices.     

Two-Phase Thermal Transport in Microgap Channels—Theory,Experimental Results,and Predictive Relations

A comprehensive literature review and analysis of recent microchannel/microgap heat transfer data for two-phase flow of refrigerants and dielectric liquids is presented. The flow regime progression in such a microgap channel is shown to be predicted by the traditional flow regime maps. Moreover, Annular flow is shown to be the dominant regime for this thermal transport configuration and to grow in importance as the channel diameter decreases. The results of heat transfer studies of single miniature channels, as well as the analysis and inverse calculation of IR images of a heated microgap channel wall, are used to identify the existence of a characteristic M-shaped heat transfer coefficient variation with quality (or superficial velocity), with inflection points corresponding to transitions in the two-phase cooling modalities. For the high-quality, Annular flow conditions, the venerable Chen correlation is shown to yield predictive agreement for microgap channels that is comparable to that attained for macrochannels and to provide a mechanistic context for the thermal transport rates attained in microgap channels. Results obtained from infrared imaging, revealing previously undetected, large surface temperature variations in Annular flow, are also reviewed and related to the termination of the favorable thin-film evaporation mode in such channels.     

Taki Kōji,Provoke, and the Structuralist Turn in Japanese Image Theory, 1967–70

This article explores the intellectual underpinnings of the late-1960s Japanese photography collective Provoke. It argues that Provoke was more radical and theoretically inflected than is conventionally understood, its project being the forging of a ‘scientific’ photography capable of unveiling the ‘untruth’ of established relations of power and knowledge production in Japan. I present Provoke’s central figure to be Taki Kōji, who in 1967–68 published a series of articles that introduced structuralism into Japanese image discourse and established the basis for Provoke’s theoretically informed practice, or praxis. The article outlines how, in response to a variety of influences (Roland Barthes, Matsumoto Toshio, and Kevin Lynch, among others, but apparently not Antonio Gramsci or Louis Althusser), Taki formulated the notion of a unified and self-regulating ideological ‘environment’ (kankyō) that is made manifest in a variety of seemingly neutral and benign cultural forms. Additionally, he theorised a semiotically transgressive photographic image, derived from Barthes’s early studies of photography, which he believed could escape language and code – and thereby the ideological superstructure. I conclude by showing that Taki’s emancipatory project, while singular in relation to contemporaneous Marxist oppositional endeavours in Europe, was ultimately self-defeating: the efforts of Provoke’s photographers to strip their images of readable codes by deliberately ‘mishandling’ their cameras only worked to create new ones, and the shakiness and blurriness of the resulting photographs became a mere style.