Mixture ratio modeling of dynamic systems

Any knowledge extraction relies (possibly implicitly) on a hypothesis about the modelled-data dependence. The extracted knowledge ultimately serves to a decision-making (DM). DM always faces uncertainty and this makes probabilistic modelling adequate. The inspected black-box modeling deals with “universal” approximators of the relevant probabilistic model. Finite mixtures with components in the exponential family are often exploited. Their attractiveness stems from their flexibility, the cluster interpretability of components and the existence of algorithms for processing high-dimensional data streams. They are even used in dynamic cases with mutually dependent data records while regression and auto-regression mixture components serve to the dependence modeling. These dynamic models, however, mostly assume data-independent component weights, that is, memoryless transitions between dynamic mixture components. Such mixtures are not universal approximators of dynamic probabilistic models. Formally, this follows from the fact that the set of finite probabilistic mixtures is not closed with respect to the conditioning, which is the key estimation and predictive operation. The paper overcomes this drawback by using ratios of finite mixtures as universally approximating dynamic parametric models. The paper motivates them, elaborates their approximate Bayesian recursive estimation and reveals their application potential.     

Semantic Mediation for Standard-Based B2B Interoperability

The authors discuss a semantic-mediation architecture to advance traditional approaches for standards-based business-to-business (B2B) interoperability. The architecture is supported by the Athena Knowledge Representation and Semantics Mediation tool suite. Initial experimentations with the architecture and the toolset offer discussions of key architectural and functional aspects and suggest directions for future tools enhancements.     

Internalization and Accumulation in Dendritic Cells of a Small pH‐Activatable Glycomimetic Fluorescent Probe as Revealed by Spectral Detection

DC‐SIGN, an antigen‐uptake receptor in dendritic cells (DCs), has a clear role in the immune response but, conversely, can also facilitate infection by providing entry of pathogens into DCs. The key action in both processes is internalization into acidic endosomes and lysosomes. Molecular probes that bind to DC‐SIGN could thus provide a useful tool to study internalization and constitute potential antagonists against pathogens. So far, only large molecules have been used to directly observe DC‐SIGN‐mediated internalization into DCs by fluorescence visualization. We designed and synthesized an appropriate small glycomimetic probe. Two particular properties of the probe were exploited: activation in a low‐pH environment and an aggregation‐induced spectral shift. Our results indicate that small glycomimetic molecules could compete with antigen/pathogen for binding not only outside but also inside the DC, thus preventing the harmful action of pathogens that are able to intrude into DCs, for example, HIV‐1.     

Large‐Scale Experiments on the Formation of Surface Vortices with and without Vortex Suppression

Experiments were carried out in a 50‐m³ cylindrical tank to determine the influence of strong momentum on the formation of large‐scale gas‐core vortices. Gas‐core lengths were measured for varying volume flow rates and submergence depths. The critical Froude numbers were also determined and the efficiency of different vortex suppressors on the gas‐core formation was investigated. The horizontal velocity field inside the vortex core region was additionally recorded using particle image velocimetry. The experimental results were used to verify numerical simulations and compared to vortex models and correlations from literature.     

A Pyropheophorbide Analogue Containing a Fused Methoxy Cyclohexenone Ring System Shows Promising Cancer-Imaging Ability

Herein we report the synthesis, photophysical properties, positron emission tomography (PET) imaging and photodynamic therapy (PDT) efficacy of methyl 3-(1′-m-iodobenzyloxy)ethyl-3-devinyl-verdin 4 (with or without the ¹²⁴I isotope). The PET imaging ability and ex vivo biodistribution of [¹²⁴I] 4 were compared with the well-studied methyl [3-(¹²⁴1′-m-iodobenzyloxy)ethyl]-3-devinyl-pyropheophorbide-a methyl ester (PET-ONCO or [¹²⁴I] 2 ) and [¹⁸F]fluorodeoxyglucose ([¹⁸F]FDG) in BALB/c mice bearing colon-26 tumors. Whole-body PET images of [¹²⁴I] 4 containing a fused methoxy cyclohexenone ring system showed excellent tumor contrast with time (72>48>24 h post-injection). Ex vivo biodistribution results indicate that relative to the current clinical standard [¹⁸F]FDG and [¹²⁴I] 2 in 2 % ethanol formulation, [¹²⁴I] 4 , at the same radioactive dose (25 μCi per mouse), showed higher tumor uptake at 24 h post-injection and longer tumor retention. In biological environments, compound 4 showed lower fluorescence and lower singlet oxygen yield than 2 , which is possibly due to higher aggregation caused by the presence of a fused cyclohexenone ring system, resulting in limited in vitro/in vivo PDT efficacy. Therefore, the chlorophyll-a analogue [¹²⁴I] 4 provides easy access to a novel PET imaging agent (with no skin phototoxicity) to image cancer types—brain, renal carcinomas, pancreas—in which [¹⁸F]FDG shows limitations.     

Light stability in cyan and magenta tones using standard and highly chromatic toner particles

An increasing requisite regarding the reproduction quality of electrophotographic printing machines demands improvement of new electrophotographic toner formulation, especially used pigments. The subject of this paper is a comparison of prints realised by depositing high chroma (HC) and standard emulsion aggregation (EA) toner on gloss fine art paper. HC toner has a different composition of the cyan and magenta tones compared with the corresponding standard EA toner tones and therefore behaves differently under real conditions. The patches used for this experiment were cyan and magenta tone prints with tone values (TVs) of 0, 20, 60 and 100%. Ultraviolet (UV) degradation was measured over time intervals of 0, 6, 12, 24, 48, 96, 144 and 240 h for all patches. Results (laboratory values) were calculated using colorimetric difference. Values were plotted as a function of time in tonal degradation graphs. A model was created using non‐linear regression‐based modelling. The experiment demonstrates that magenta patches are more susceptible to degradation in comparison with cyan patches. With the increase in tonal value, it is noticeable that the colorimetric difference is higher. Colorimetric differences calculated using HC magenta toner and standard EA cyan toner (100% TV) were higher than ?E = 5, starting to appear after 6 h of exposure to UV radiance. After 12 h of exposure, colorimetric differences of standard magenta tones that were greater than ?E = 5 also started to appear. Cyan patches (100% TV) printed with HC toner were more stable than the other patches, and after 240 h of exposure had not crossed the boundary of ?E = 5.     

Stationary and Progressive Phenotypes Caused by the p.G90D Mutation in Rhodopsin Gene

Mutations in rhodopsin gene (RHO) are a frequent cause of retinitis pigmentosa (RP) and less often, congenital stationary night blindness (CSNB). Mutation p.G90D has previously been associated with CSNB based on the examination of one family. This study screened 60 patients. Out of these 60 patients, 32 were affected and a full characterization was conducted in 15 patients. We described the clinical characteristics of these 15 patients (12 male, median age 42 years, range 8–71) from three families including visual field (Campus Goldmann), fundus autofluorescence (FAF), optical coherence tomography (OCT) and electrophysiology. Phenotypes were classified into four categories: CSNB (N = 3, 20%) sector RP (N = 3, 20%), pericentral RP (N = 1, 6.7%) and classic RP (N = 8, 53.3% (8/15)). The phenotypes were not associated with family, sex or age (Kruskal–Wallis, p > 0.05), however, cystoid macular edema (CME) was observed only in one family. Among the subjects reporting nyctalopia, 69% (22/32) were male. The clinical characteristics of the largest p.G90D cohort so far showed a large frequency of progressive retinal degeneration with 53.3% developing RP, contrary to the previous report.     

Involvement of IL-4, IL-13 and Their Receptors in Pancreatic Cancer

Interleukin (IL)-4 and IL-13 are known as pleiotropic Th2 cytokines with a wide range of biological properties and functions especially in immune responses. In addition, increasing activities have also been determined in oncogenesis and tumor progression of several malignancies. It is now generally accepted that IL-4 and IL-13 can exert effects on epithelial tumor cells through corresponding receptors. Type II IL-4 receptor (IL-4Rα/IL-13Rα1), predominantly expressed in non-hematopoietic cells, is identified to be the main target for both IL-4 and IL-13 in tumors. Moreover, IL-13 can also signal by binding to the IL-13Rα2 receptor. Structural similarity due to the use of the same receptor complex generated in response to IL-4/IL-13 results in overlapping but also distinct signaling pathways and functions. The aim of this review was to summarize knowledge about IL-4 and IL-13 and their receptors in pancreatic cancer in order understand the implication of IL-4 and IL-13 and their receptors for pancreatic tumorigenesis and progression and for developing possible new diagnostic and therapeutic targets.     

Recombination and loss mechanisms in low-threshold InAs-GaAs 1.3-/spl mu/m quantum-dot lasers

We show that even in quantum-dot (QD) lasers with very low threshold current densities (J/sub th/=40--50 A/cm/sup 2/ at 300 K), the temperature sensitivity of the threshold current arises from nonradiative recombination that comprises /spl sim/60% to 70% of J/sub th/ at 300 K, whereas the radiative part of J/sub th/ is almost temperature insensitive. The influence of the nonradiative recombination mechanism decreases with increasing hydrostatic pressure and increasing band gap, which leads to a decrease of the threshold current. We also studied, for the first time, the band gap dependence of the radiative part of J/sub th/, which in contrast increases strongly with increasing band gap. These results suggest that Auger recombination is an important intrinsic recombination mechanism for 1.3-/spl mu/m lasers, even in a very low threshold QD device, and that it is responsible for the temperature sensitivity of the threshold current.