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[Display omitted] Cannabidiol (CBD) suffers from poor oral bioavailability due to poor aqueous solubility and high metabolism, and is generally administered in liquid lipid vehicles. Solid-state formulations of CBD have been developed, but their ability to increase the oral bioavailability has not yet been proven in vivo. Various approaches are investigated to increase this bioavailability. This study aimed to demonstrate the enhancement of the oral bioavailability of oral solid dosage forms of amorphous CBD and lipid-based CBD formulation compared to crystalline CBD. Six piglets received the three formulations, in a cross-over design. CBD and 7 − COOH − CBD, a secondary metabolite used as an indicator of hepatic degradation, were analyzed in plasma. A 10.9-fold and 6.8-fold increase in oral bioavailability was observed for the amorphous and lipid formulations, respectively. However, the lipid-based formulation allowed reducing the inter-variability when administered to fasted animals. An entero-hepatic cycle was confirmed for amorphous formulations. Finally, this study showed that the expected protective effect of lipids against hepatic degradation of the lipid-based formulation did not occur, since the ratio CBD/metabolite was higher than that of the amorphous one. [ABSTRACT FROM AUTHOR]

[Display omitted] Among the various 3D printing techniques, FDM is the most studied in pharmaceutical research. However, it requires the fabrication of filaments with suitable mechanical properties using HME, which can be laborious and time-consuming. DPE has emerged as a single-step printing technique that can overcome FDM limits as it enables the direct printing of powder blends without the need of filaments. This study demonstrated the manufacturing of cylindrical-shaped printed tablets containing CBD, a BCS II molecule, with an immediate release. Different blends of PEO/E100 and PEO/SOL, each with 10 % of CBD, were printed and tested according to the Eur. Ph. for uncoated tablets. Each printed cylinder met the Eur. Ph. specifications for friability, mass variation and mass uniformity. However, only the E100-based formulations enabled a CBD immediate release, as formulations containing SOL formed a gel once in contact with the dissolution medium, reducing the drug dissolution rate. [ABSTRACT FROM AUTHOR]

Many palaeontological studies have investigated the evolution of entire body plans, generally relying on discrete character-taxon matrices. In contrast, macroevolutionary studies performed by neontologists have mostly focused on morphometric traits. Although these data types are very different, some studies have suggested that they capture common patterns. Nonetheless, the tests employed to support this claim have not explicitly incorporated a phylogenetic framework and may therefore be susceptible to confounding effects due to the presence of common phylogenetic structure. We address this question using the scorpion genus Brachistosternus Pocock 1893 as case study. We make use of a time-calibrated multilocus molecular phylogeny, and compile discrete and traditional morphometric data sets, both capturing the overall morphology of the organisms. We find that morphospaces derived from these matrices are significantly different, and that the degree of discordance cannot be replicated by simulations of random character evolution. Moreover, we find strong support for contrasting modes of evolution, with discrete characters being congruent with an 'early burst' scenario whereas morphometric traits suggest species-specific adaptations to have driven morphological evolution. The inferred macroevolutionary dynamics are therefore contingent on the choice of character type. Finally, we confirm that metrics of correlation fail to detect these profound differences given common phylogenetic structure in both data sets, and that methods incorporating a phylogenetic framework and accounting for expected covariance should be favoured. [ABSTRACT FROM AUTHOR]

The energy level alignment at interfaces between organic semiconductors is of direct relevance to understand charge carrier generation and recombination in organic electronic devices. Commonly, work function changes observed upon interface formation are interpreted as interface dipoles. In this study, using ultraviolet and X-ray photoelectron spectroscopy, complemented by electrostatic calculations, we find a huge work function decrease of up to 1.4eV at the C60 (bottom layer)/zinc phthalocyanine (ZnPc, top layer) interface prepared on a molybdenum trioxide (MoO3) substrate. However, detailed measurements of the energy level shifts and electrostatic calculations reveal that no interface dipole occurs. Instead, upon ZnPc deposition, a linear electrostatic potential gradient is generated across the C60 layer due to Fermi level pinning of ZnPc on the high work function C60/MoO3 substrate, and associated band-bending within the ZnPc layer. This finding is generally of importance for understanding organic heterojunctions when Fermi level pinning is involved, as induced electrostatic fields alter the energy level alignment significantly. [ABSTRACT FROM AUTHOR]

[Display omitted] The objective of this work was to evaluate the impact of physico-chemical properties of pharmaceutical drugs on the optimal mesoporous silica loading methods. Indeed, a good combination between drug and loading process has to be studied to promote the deepest penetration of the drug inside the mesopores, allowing high drug amorphization. Six molecules, namely lidocaine and its hydrochloride, ibuprofen, ketoprofen, artemether and miconazole, with different physico-chemical properties (the ionized character, the acid-base character, the HBDA number, the solubility in sc-CO 2 and the behavior under subcritical CO 2) were used to produce drug-silica formulations. Different impregnation processes (physical mixing, melting, wetting, sc-CO 2 and subcritical CO 2 impregnations) have been compared for each drug, in terms of drug recovery and crystallinity. Formulations showed drug percentage close to 100% except for supercritical soluble drug formulations impregnated by using sc-CO 2. However, the basic drug character provided less or no drug loss during impregnation. Processing insoluble sc-CO 2 molecule under supercritical conditions led to less crystallinity than the correspondent physical mixture suggesting an interesting repulsive effect that forces the drug penetration within the mesopores. Besides, it has been also highlighted that the HBDA number is not sufficient to predict the final drug loading. Melting methods have high interest considering the drugs tested and subcritical CO 2 could increase the loading, especially for drugs with high molten viscosity. This study showed that a plethora of loading methods can be used to provide high drug loaded MS formulations with a wide choice of equipment. [ABSTRACT FROM AUTHOR]

Software development techniques are continuously evolving with the goal of solving the main problems that still affect the building and maintenance of software systems: time, costs and error-proneness. Model-driven engineering (MDE) approaches aim to reduce at least some of these problems providing techniques for the construction of models and the specification of transformation rules, tool support and automatic generation of code and documentation. The method of resolution of MDE is to first build models, which are independent of the platform, transforming them in later stages to technological-dependent models, and to achieve automatic model and code generation based on transformation rules. Web engineering is a domain where model-driven approaches can be used to address evolution and adaptation of Web software to continuously emerging new platforms and changes in technologies. We present an overview of the development process of the Unified Modelling Language (UML)-based Web engineering (UWE) defined as an MDE approach. The main characteristic of UWE is the use of standards including the UML, XML metadata interchange as model exchange, meta-object facility for metamodelling, model-driven architecture and the transformation language query-view-transformation. We focus on the model transformation aspects of the UWE process. [ABSTRACT FROM AUTHOR]

Abstract: We used ultraviolet photoelectron spectroscopy (UPS) to investigate the energy level alignment at contacts between pentacene and Ag(111) in the presence of interfacial 6,13-pentacenequinone (PQ). Depending on the metal pre-coverage with PQ, we found evidence for three distinctly different interface morphologies and molecular orientations, accompanied by significant changes of the energy level alignment. Consequently, the hole injection barrier between pentacene and Ag(111) varied between 1.1eV (pristine Ag) and 0.45eV (5.4nm PQ pre-coverage on Ag). In addition, our UPS results suggest that PQ can act as deep trap for electrons in a pentacene matrix. Depending on the exact mutual orientation of PQ and pentacene, the depth of these traps can be in the range of 0.2–0.75eV. [Copyright &y& Elsevier]

Abstract: The diagnostics of focal nodular hyperplasia is reached through the use of imaging. When the diagnostic is certain, surgical abstention is the rule. Nevertheless, we were confronted with two cases of a rare complication; that of intraperitoneal rupture. In this situation, we suggest to first do an arteriography to control the bleeding, then to perform surgery when the patient has reached hemodynamic stability. Spontaneous rupture as a complication of benign nodular hyperplasia remains a rare event and only five cases were reported in litterature. [Copyright &y& Elsevier]

Abstract: We present ultraviolet photoelectron spectroscopy studies on alkali metal-intercalated thin films of electroluminescent p-sexiphenyl (6P) and the organic hole transporting material N,N′-bis-(1-naphthyl)-N,N′-diphenyl1-1,1-biphenyl1-4,4′-diamine (α-NPD). The formation of new occupied electronic states in the otherwise empty energy gap of 6P and α-NPD is observed, accompanied by a significant shift of the Fermi-level. Depending on the work function ϕ of the substrate used for the organic thin films, we observe two different scenarios at low intercalation levels: the new electronic states are observed at (and even above) E F for high ϕ substrates, whereas they are observed below E F for low ϕ substrates. At high intercalation levels, all the states are observed below E F. The observation of states at and above E F is attributed to a lack of thermodynamic equilibrium across the organic thin film. [Copyright &y& Elsevier]

Abstract: Ultraviolet photoemission spectroscopy was used to determine the work function φ and the hole injection barriers Δh of interfaces formed between pentacene and two fundamentally different electrode materials: (i) conductive polymers comprising poly(3,4-ethylenedioxythiophene) and sulfonate moieties, and (ii) Au with chemisorbed Cl. φ of these substrates before pentacene deposition covers a wide range of 4.25–5.15eV for the polymers, and extends to 5.8eV for Au–Cl. Despite this huge variation in φ, Δh after pentacene deposition is found to be almost identical for all cases (≉0.35eV). The mechanism responsible for Δh being independent of initial surface φ is proposed to be an interfacial charge transfer reaction leading to cationic pentacene species. These findings are compared to interfaces between pentacene and clean metal surfaces, where Δh was found to decrease with increasing substrate φ. [Copyright &y& Elsevier]

The effect of the grain-shape (`morphological') texture of a polycrystal on the mechanical elastic constants and diffraction (X-ray) stress factors is investigated. To this end, the Eshelby-Kröner grain interaction model originally devised for polycrystals consisting of spherical grains is extended to ellipsoidal grain morphology. Results obtained for the mechanical elastic constants show that a polycrystal consisting of ellipsoidal grains with their principal axes aligned along common directions (i.e. when an ideal grain-shape texture occurs) is macroscopically elastically anisotropic. Also the diffraction (X-ray) stress factors are affected by the grain-shape texture; they reflect the macroscopic elastic anisotropy by resulting in nonlinear so-called sin² ψ plots. In general, a grain-shape texture can have a moderate effect on the mechanical elastic constants and a pronounced effect on the diffraction elastic constants, depending on the crystal symmetry and single-crystal elastic a nisotropy. [ABSTRACT FROM AUTHOR]

The formation of small gold clusters at the initial stage of the metal growth on a thin film of the conjugated organic semiconductor diindenoperylene (DIP) leads to charging during ultraviolet photoemission spectroscopy (UPS) investigations. Additional irradiation of the sample with visible light was successfully applied to re-establish charge neutrality on the sample surface. By varying the light energy, we demonstrate that the optical formation of excitons and/or polarons results in efficient electron transfer from DIP to the positively charged Au clusters and thus the elimination of charging in UPS. This allows the collection of reliable information on the interface electronic structure. [Copyright &y& Elsevier]

Discusses a source of highly dissociated, intense, cold hydrogen and deuterium atomic beams to be used as a dissociator in polarized gas targets for storage ring experiments. Plasma source that couples a surface wave to the discharge; Formation of a cold atomic beam by means of a cooled nozzle; Optimization of the system to obtain a beam with a high atomic fraction.

The barley yellow dwarf virus (BYDV) epidemics, which occurred predominantly in northern Germany in 1988-90 and caused unusual yield losses of wheat, prompted our study on interactions of BYDV and Fusarium culmorum. At the late stages of plant development (EC 55/65) infections with BYDV resulted in a lower yield reduction of wheat plants than infections with F. culmorum. Combined infections at flowering resulted in severer yield reduction, indicating additive effects of the two pathogens. However, if wheat infected by BYDV at stage EC 25/35 was secondarily inoculated with the fungus at EC 55/65 the yield was less reduced than in combined infections at EC 55/65. Our results proved that the susceptibility of wheat plants to F. culmorum is increased when infection by BYDV takes place during the late stages of growth. These results correspond to observations during 3 years of the epidemic in Germany. In these years BYDV was spread mainly during the late spring, resulting in a severe secondary infection by the fungus. From the results of these investigations it may be concluded that during the years of BYDV epidemic the yield of wheat was reduced to an economically important extent because of the fungal infection, which was favoured by the virus infection. [ABSTRACT FROM AUTHOR]

Interface formation between the organic semiconductor α-sexithiophene (6T) and polar as well as nonpolar ZnO surfaces is investigated. The growth mode of the organic layer is strongly influenced by the orientation of the ZnO surface. No indication for chemisorption of 6T on ZnO is found by photoelectron spectroscopy. The energy level alignment at the 6T/ZnO interface is of type-II facilitating electron transfer from the organic to the inorganic part and hole transfer in the other direction, rendering this heterostructure interesting for photovoltaic applications. [ABSTRACT FROM AUTHOR]

The influence of water exposure on the work function ([lowercase_phi_synonym]) and surface composition of conducting poly(3,4-ethylenedioxythiophene)/poly(styrenesulfonate) (PEDT:PSS) was investigated with ultraviolet and x-ray photoelectron spectroscopies. It was found that annealing PEDT:PSS in vacuum to 220 °C yields a high [lowercase_phi_synonym] of 5.65 eV. Subsequent exposure to water vapor or air reduces [lowercase_phi_synonym] to ∼5.15 eV, and the film surface becomes enriched with PEDT. These observations were fully reversible for repeated annealing–water exposure cycles. The reduction in [lowercase_phi_synonym] is attributed to (i) the inclusion of water leading to a larger dielectric constant and (ii) polymer swelling-induced rearrangements of surface dipoles. [ABSTRACT FROM AUTHOR]

Recently, mesoporous silica (MS) has been used as a material able to maintain amorphous state of active compounds and therefore, enhance the oral bioavailability of BCSII drugs. Among impregnation methods of MS, techniques using supercritical carbon dioxide (Sc-CO 2) are promising tools. Solubility of compounds in Sc-CO 2 is reported as one of the most critical parameters, which usually limits its use in drug formulation. Indeed, most of compounds have poor solubility in Sc-CO 2. The aim of this work is to compare different MS and to study alternative processes using pressurized CO 2 for insoluble molecule in Sc-CO 2. By using high pressure reactor, DSC, HPLC and in vitro dissolution tests, the crystallinity and dissolution profiles of MS with different pore size (6.6 nm, 25.0 nm and 2.5 nm) impregnated with fenofibrate (FF) under Sc-CO 2 were compared to select the most appropriate carrier. Then, the selected MS has been impregnated under supercritical, subcritical and atmospheric conditions. We have shown that the MS pore size of 6.6 nm provides the higher amorphous drug loading capacity as well as the faster and higher drug dissolution. In addition, FF-MS formulations produced with pressurized CO 2 as fusion medium, both in subcritical and supercritical conditions; give similar crystallinity and dissolution results compared to those produced with supercritical fluids as solvent. Through this study, we show new possibilities of using CO 2 for insoluble compounds in this fluid. [ABSTRACT FROM AUTHOR]

Contacts between two molecular organic semiconductors [p-sexiphenyl (6P) and pentacene] and conducting polymers (CPs) were investigated with photoemission spectroscopy. The dependence of the hole injection barrier (HIB) at 6P/CP interfaces on substrate work function ([lowercase_phi_synonym]) exhibited a transition from almost Schottky-Mott limit-like behavior to Fermi-level pinning. For pentacene, no significant variation of the HIB as function of [lowercase_phi_synonym] was observed, despite the large range of [lowercase_phi_synonym] spanned by the CPs (4.4–5.9 eV). The results on contacts with CPs are compared to those with metals, where none of the two limiting cases for HIBs as a function of [lowercase_phi_synonym] was observed. [ABSTRACT FROM AUTHOR]

The current-voltage characteristics I(V) of model organic devices are studied under ultra-high-vacuum conditions. Active materials are N,N'-bis-(1-naphthyl)-N,N'-diphenyll - 1,1-biphenyl1-4,4'- diamine (α-NPD) and pentacene, electrode materials are polycrystalline Au and the conductive polymer poly(3,4-ethylenedioxythiophene)/poly(styrenesulfonate) (PEDOT/ PSS). Despite a similar work function of electrode material surfaces (∼ 5 eV), hole injection from PEDOT/PSS is significantly more efficient than from Au, due to a smaller hole injection barrier. Hole injection characteristics from Au electrodes for devices made from α-NPD are independent of deposition sequence and substrate used. Pentacene devices exhibit serious asymmetries in that respect. These are caused by a strong dependence of morphology and preferred molecular orientation on the substrate for the crystalline material. [ABSTRACT FROM AUTHOR]

Ultraviolet photoemission spectroscopy is used to determine the energy level alignment at interfaces between three electroactive conjugated organic molecular materials, i.e., N,N'-bis-(1-naphthyl)-N,N'-diphenyll-1,1-biphenyll-4,4' -diamine; para-sexiphenyl; pentacene, and two high work function electrode materials, i.e., gold and poly(3,4-ethylenedioxythiophene)/ poly(styrenesulfonate). Although both electrode surfaces have a similar work function (∼ 5 eV), the hole injection barrier and the interfacial dipole barrier are found to be significantly smaller for all the interfaces formed on the polymer as compared to the metal. This important and very general result is linked to one of the basic mechanisms that control molecular level alignment at interfaces with metals, i.e., the reduction of the electronic surface dipole contribution to the metal work function by adsorbed molecules. [ABSTRACT FROM AUTHOR]

Demonstrates that highly efficient single-layer light emitting devices can be realized by better control in the device production process. Cross section of the device studied using Auger depth profiling and spectroscopy; Interface between the active material and the metal cathode; Concentration of oxygen at the cathode interface.

In order to correlate the molecular orientation of organic thin films with charge injection barriers at organic/metal interfaces, the electronic structure and molecular orientation of vacuum sublimed thin films of α,ω-dihexylsexithiophene (DH6T) on the substrates Ag(111), highly oriented pyrolytic graphite (HOPG), and tetratetracontane (TTC) precovered Ag(111) were investigated. Results from metastable atom electron spectroscopy, ultraviolet photoelectron spectroscopy, and x-ray diffraction were used to derive growth models (including molecular orientation and conformation) of DH6T on the different substrates. On Ag(111), DH6T exhibits a transition from lying molecules in the monolayer/bilayer range to almost standing upright molecules in multilayers. This is accompanied by a shift of the molecular energy levels to a lower binding energy by 0.65 eV with respect to the vacuum level. The unit cell of standing DH6T on lying DH6T on Ag(111) is estimated to be similar to the DH6T bulk phase. On HOPG, DH6T grows in the bulk phase with lying orientation, starting already from the monolayer coverage. DH6T on TTC precovered Ag(111) grows in an almost lying orientation and a conformation that allows a strong overlap of the hexyl chains of DH6T with the alkyl chains of TTC. In all cases, the electronic structure and, particulary, the ionization energy of DH6T is dependent on the orientation of DH6T, i.e., lying DH6T has higher ionization energy than standing DH6T. [ABSTRACT FROM AUTHOR]

The formation of the interface between a thin film of a ladder-type poly(para-phenylene) m-LPPP and aluminum was investigated with x-ray and ultraviolet photoemission spectroscopy. The physical properties of this interface are of actual interest as m-LPPP is successfully applied as active material in organic light emitting devices (LED). Almost no changes in the core-level and valence electronic structure of the polymer upon increasing coverage with aluminum (in situ) are found. This gives indication for a weak interaction of Al with m-LPPP, ruling out the formation of chemical bonds between the two materials. The rapid occurrence of metallic aluminum at rather low coverage in the presented experiment is an important finding for the understanding of charge injection and the interfacial electronic structure in organic LEDs. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]

In applications, surface states and bulk doping concentration are important parameters of inorganic semiconductors, as they determine the bulk properties and substantially influence the properties of interfaces in devices, foremost the electron energy level alignment. In this work, we provide a qualitative model to describe the influence of surface state density and bulk donor concentration on the work function increase upon deposition of strong organic molecular acceptors onto the surface of n-doped inorganic semiconductors. This work function increase due to electron transfer to the molecular layer has two contributions: the formation of an interface dipole and a change of the near-surface space charge region inside the inorganic semiconductor, referred to as surface band bending. By using different surface preparation methods, we show how the surface state density limits the surface band bending change and enhances the interface dipole, both measured independently by photoelectron spectroscopy. In addition, we show that bulk donor concentration variation of the inorganic semiconductor has minor influence on the ratio of the two contributions to the work function change, at least for low to moderate donor concentrations up to 1019 cm−3. [ABSTRACT FROM AUTHOR]

An energy analysis was performed on the Eucalyptus grandis production system practiced in Hawaii with a system boundary defined as the edge of the plantation. Mass and energy flows crossing this boundarywere inventoried over a seven year production rotation and unit factors were applied to convert mass and energy flows to a common energy basis, MJ per hectare. Based on a seven year harvest rotation, energy equivalents of production inputs totaled 46.5 GJ ha-1. Energy used in harvesting, primarily diesel fuel, accounted for ~70% of the total energy input to the system. Herbicide and nitrogen fertilizer contributed 16.9% and 7.1% of the total, respectively, and were the second and third largest input energy flow streams. E. grandis wood was the sole energy output from the system and averaged 290 GJ ha-1 yr-1 at the Hamakua plantation site. The total wood energy harvested from the system was estimated at 2.0 TJ ha-1. The input and output energy flows were used to calculate energy ratios for lower altitude and higher altitude plantation sites of 43.7 and 40.8 units of wood energy produced per unit of fossil energy input, respectively. Methods that will be used to harvest plantation E. grandis in Hawaii are currently not well established. Equipment selection, machine productivity (ha harvested h-1), and fuel consumption rates are important factors in the input energy total. Replacing assumptions with data from actual practice will reduce uncertainty and potentially improve energy ratio values. [ABSTRACT FROM AUTHOR]