Synthesis and Biological Evaluation of Nipecotic Acid and Guvacine Derived 1,3-Disubstituted Allenes as Inhibitors of Murine GABA Transporter mGAT1

A new class of nipecotic acid and guvacine derivatives has been synthesized and characterized for their inhibitory potency at mGAT1–4 and binding affinity for mGAT1. Compounds of the described class are defined by a four-carbon-atom allenyl spacer connecting the nitrogen atom of the nipecotic acid or guvacine head with an aromatic residue. Among the compounds investigated, the mixture of nipecotic acid derivatives rac-{(R_a)-1-[4-([1,1′:2′,1′′-terphenyl]-2-yl)buta-2,3-dien-1-yl](3R)-piperidine-3-carboxylic acid} and rac-{(S_a)-1-[4-([1,1′:2′,1′′-terphenyl]-2-yl)buta-2,3-dien-1-yl](3R)-piperidine-3-carboxylic acid} ( 21 p ), possessing an o-terphenyl residue, was identified as highly selective and the most potent mGAT1 inhibitor in this study. For the (R)-nipecotic acid derived form of 21 p , the inhibitory potency in [³H]GABA uptake assays was determined as pIC₅₀=6.78±0.08, and the binding affinity in MS Binding Assays as pK_i=7.10±0.12. The synthesis of the designed compounds was carried out by a two-step procedure, generating the allene moiety via allenylation of terminal alkynes which allows broad variation of the terminal phenyl and biphenyl subunit.     

Source proximity and outdoor-residential VOC concentrations: results from the RIOPA study

Ambient volatile organic compound concentrations outside residences were measured in Elizabeth, New Jersey as part of the Relationship of Indoor, Outdoor, and Personal A:r (RIOPA) study to assess the influence of proximity of the residences to known ambient emissions sources. The closest distances between the outdoor samplers and emission sources were determined using Geographic Information Systems (GIS)techniques. Multiple regression models were developed for residential ambient concentrations of aromatic hydrocarbons (BTEX), methyl tert butyl ether (MTBE), and tetrachloroethylene (PCE). The natural log transformed ambient concentrations of BTEX were inversely associated with distances to major roadways with high traffic densities and gasoline stations, atmospheric stability, temperature, and wind speed. Ambient MTBE levels were associated with inverse distance to gas stations and interstate highways. Residential ambient PCE concentration was inversely associated with distance to dry cleaning facilities, atmospheric stability, temperature, wind speed, and relative humidity. The linear regression models that include proximity to emission sources and meteorological variables explained 16-45% of the overall variation of ambient residential VOC concentrations. Meteorological conditions, especially atmospheric stability and temperature, explained 60-90% of the total variation in the regression models. The residential ambient air concentrations were 1.5-4 times higher than the urban background levels outside homes very close (<50 m) to ambient emission sources where approximately 7% of the population live. However, the relative increase of risk for disease is small and variations in air concentration in the background urban atmosphere are greater than those from the proximity to roadways.     

Achieving High Efficiency and Improved Stability in ITO‐Free Transparent Organic Light‐Emitting Diodes with Conductive Polymer Electrodes

Efficient transparent organic light‐emitting diodes (OLEDs) with improved stability based on conductive, transparent poly(3,4‐ethylenedioxythiophene): poly(styrenesulfonate) (PEDOT:PSS) electrodes are reported. Based on optical simulations, the device structures are carefully optimized by tuning the thickness of doped transport layers and electrodes. As a result, the performance of PEDOT:PSS‐based OLEDs reaches that of indium tin oxide (ITO)‐based reference devices. The efficiency and the long‐term stability of PEDOT:PSS‐based OLEDs are significantly improved. The structure engineering demonstrated in this study greatly enhances the overall performances of ITO‐free transparent OLEDs in terms of efficiency, lifetime, and transmittance. These results indicate that PEDOT:PSS‐based OLEDs have a promising future for practical applications in low‐cost and flexible device manufacturing.     

Exergy analysis of PEM fuel cells for marine applications

Fuel cells have a promising potential use in stationary and mobile power generation systems, as well as in automotive, aerospace or marine industries. At present, the main field of marine applications of fuel cells is submarines. Hydrogen/oxygen polymer electrolyte membrane (PEM) fuel cells are commonly used in this field. Storage of oxygen in liquid form is the optimal solution. Hydrogen can be stored in carbon-nanofibres or metallic hydrides, for example, or in liquid fuels, as alcohols, with further generation of the hydrogen required on-board. The objective of this study is to perform an exergetic analysis of two possibilities of using PEM fuel cells on surface ships and submarines: hydrogen/oxygen PEM fuel cells fed with hydrogen generated by reforming of methanol, and Direct Methanol Fuel Cells directly fed with liquid methanol. To do this, exergy losses and exergetic efficiencies are calculated for both configurations at selected optimal operation points.     

POSIX file store in Z/Eves: An experiment in the verified software repository

We present results from the second pilot project in the international Verification Grand Challenge: a formally verified specification of a POSIX-compliant file store using the Z/Eves theorem prover. The project’s overall objective is to build a verified file store for space-flight missions. Our specification of the file store is based on Morgan and Sufrin’s specification of the UNIX filing system; the proof and its mechanisation in Z/Eves are novel. We show how our work contributes towards building a verified software repository: a set of general theories, proof techniques, and experiments reusable across different domains.     

Towards the derivation of verbal content relations from patent claims using deep syntactic structures

Research on the extraction of content relations from text corpora is a high-priority topic in natural language processing. This is not surprising since content relations form the backbone of any ontology, and ontologies are increasingly made use of in knowledge-based applications. However, so far most of the works focus on the detection of a restricted number of prominent verbal relations, including in particular is-a, has-part and cause. Our application, which aims to provide comprehensive, easy-to-understand content representations of complex functional objects described in patent claims, faces the need to derive a large number of content relations that cannot be limited a priori. To cope with this problem, we take advantage of the fact that deep syntactic dependency structures of sentences capture all relevant content relations—although without any abstraction. We implement thus a three-step strategy. First, we parse the claims to retrieve the deep syntactic dependency structures from which we then derive the content relations. Second, we generalize the obtained relations by clustering them according to semantic criteria, with the goal to unite all sufficiently similar relations. Finally, we identify a suitable name for each generalized relation. To keep the scope of the article within reasonable limits and to allow for a comparison with state-of-the-art techniques, we focus on verbal relations.     

Hydrofluoroethers as heat-transfer fluids for OLEDs: Operational range, stability, and efficiency improvement

In this work we introduce a simple yet very efficient method of heat dissipation by immersing OLED device into hydrofluoroether (HFE) fluids. It is shown that due to highly fluorous nature of this class of fluids, HFE do not damage organic semiconductors which are comprised in the OLED stack and therefore can be used as encapsulation media. HFE also have high thermal conductivity, low viscosity and can efficiently dissipate the heat by means of natural convection with laminar flow. By employing HFE we were able to significantly improve the OLED operating dynamic range. Lifetimes of OLEDs operating in HFE at high currents can be improved by about a factor of 8. Furthermore, HFE fluid significantly improves the light outcoupling by a factor of 70% due to higher than air refractive index (n = 1.3).     

Expanding a multilingual media monitoring and information extraction tool to a new language: Swahili

The Europe Media Monitor (EMM) family of applications is a set of multilingual tools that gather, cluster and classify news in currently fifty languages and that extract named entities and quotations (reported speech) from twenty languages. In this paper, we describe the recent effort of adding the African Bantu language Swahili to EMM. EMM is designed in an entirely modular way, allowing plugging in a new language by providing the language-specific resources for that language. We thus describe the type of language-specific resources needed, the effort involved, and ways of boot-strapping the generation of these resources in order to keep the effort of adding a new language to a minimum. The text analysis applications pursued in our efforts include clustering, classification, recognition and disambiguation of named entities (persons, organisations and locations), recognition and normalisation of date expressions, as well as the identification of reported speech quotations by and about people.     

OH and CH luminescence in opposed flow methane oxy-flames

Emission spectroscopy is a 2-D nonintrusive diagnostic technique that offers spatially resolved data for combustion optimization and control. The UV and visible chemiluminescence of the excited radicals CH(A²Δ,B²Σ⁻) and OH(A²Σ⁺) is studied experimentally and numerically in opposed-flow diffusion flames of methane and oxygen-enriched air. The oxidized oxygen content is varied from 21 to 100% while the range of the studied strain rates spans from 20 to 40 s⁻¹. The spectrally resolved imaging is obtained by two different methods: scattering through a grating monochromator and interposition of interference filters along the optical path. Absolute measured chemiluminescence intensities, coupled with a numerical model based on the opposed flow flame code, are used to evaluate the chemical kinetics of the excited species. The predictions of the selected model are in good agreement with the experimental data over the range of the studied flame conditions.     

Highly Conductive PEDOT:PSS Electrode with Optimized Solvent and Thermal Post‐Treatment for ITO‐Free Organic Solar Cells

Highly conductive poly(3,4‐ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) films as stand‐alone electrodes for organic solar cells have been optimized using a solvent post‐treatment method. The treated PEDOT:PSS films show enhanced conductivities up to 1418 S cm^?1, accompanied by structural and chemical changes. The effect of the solvent treatment on PEDOT:PSS has been investigated in detail and is shown to cause a reduction of insulating PSS in the conductive polymer layer. Using these optimized electrodes, ITO‐free, small molecule organic solar cells with a zinc phthalocyanine (ZnPc):fullerene C₆₀ bulk heterojunction have been produced on glass and PET substrates. The system was further improved by pre‐heating the PEDOT:PSS electrodes, which enhanced the power conversion efficiency to the values obtained for solar cells on ITO electrodes. The results show that optimized PEDOT:PSS with solvent and thermal post‐treatment can be a very promising electrode material for highly efficient flexible ITO‐free organic solar cells.