Layer-by-layer nanostructured hybrid films of polyaniline and vanadium oxide

Supramolecular structures of polyaniline (PANI) and vanadium oxide (V2O5) have been assembled via the electrostatic layer-by-layer (ELBL) technique. Strong ionic interactions and H-bonding impart unique features to the ELBL films, which are distinct from cast films obtained with the same materials. The interactions were manifested in UV-vis and Fourier transform infrared spectroscopy data. They are enhanced by the intimate contact between the components, as the films are molecularly thin, with 25 A per PANI/V2O5 bilayer.     

Compositional specification of commercial contracts

We present a declarative language for compositional specification of contracts governing the exchange of resources. It extends Eber and Peyton Jones’s declarative language for specifying financial contracts (Jones et al. in The Fun of Programming. 2003) to the exchange of money, goods and services amongst multiple parties and complements McCarthy’s Resources, Events and Agents (REA) accounting model (McCarthy in Account Rev. LVII(3), 554–578, 1982) with a view- independent formal contract model that supports definition of user-defined contracts, automatic monitoring under execution and user-definable analysis of their state before, during and after execution. We provide several realistic examples of commercial contracts and their analyses. A variety of (real) contracts can be expressed in such a fashion as to support their integration, management and analysis in an operational environment that registers events. The language design is driven by both domain considerations and semantic language design methods: a contract denotes a set of traces of events, each of which is an alternative way of concluding the contract successfully, which gives rise to a CSP-style (Brooker et al. in J.ACM 31(3), 560–599, 1984; Hoare in Communicating Sequential Processes, 1985) denotational semantics. The denotational semantics drives the development of a sound and complete small-step operational semantics, where a partially executed contract is represented as a (full) contract that represents the remaining contractual commitments. This operational semantics is then systematically refined in two stages to an instrumented operational semantics that reflects the bookkeeping practice of identifying the specific contractual commitment a particular event matches at the time the event occurs, as opposed to delaying this matching until the contract is concluded.     

Vertical integration in distributed automation environment

Over past decades industrial IT evolved separately in the field automation and office automation domains. Nowadays increasing complexity of manufacturing requires more advanced control, which can be achieved only by integrating these, formerly separated, areas. This article focuses on two aspects of such integration: communication-related, interconnecting networks of different kinds, and functional, establishing a link between business and manufacturing processes.      

Characterization of electroplated nickel

 Properties of electroplated nickel such as crystallographic texture, Young's modulus, strength and microstructure strongly depend on the parameter mean current density used for electrodeposition. By means of micro tensile testing mechanical material parameters were determined. At low mean current density (2 mA/cm²) brittle layers with high Young's modulus and high strength were obtained, whereas at high current density (15 mA/cm²) ductile layers with low Young's modulus and low strength were deposited. Received: 10 August 2001/Accepted: 24 September 2001 Parts of the work were carried out within the project ELMINOS, which is supported by the state of North Rhine-Westphalia, Germany. The equipment used for the experiments was funded by the state of North Rhine-Westphalia. We would like to express our sincere gratitude to Mirko Hofmann for his assistance in performing the measurements of indentation hardness. The participation of Cho and Hemker was sponsored by the Defense Advanced Research Projects Agency (DARPA) and Air Force Research Laboratory, Air Force Material Command, USAF, under agreement number F30602-99-2-0553. This paper was presented at the Fourth International Workshop on High Aspect Ratio Microstructure Technology HARMST 2001 in June 2001.     

Dealing with Data Privacy Protection: An Issue for the 21st Century

In many surveys, Americans identify invasion of privacy as a primary concern. Nonetheless, newer electronic technologies, such as biometric monitoring, Web site tracking, vehicle tracking, basket-level purchase tracking, charge card usage recording, personal information database sales, release of government data to private corporations, facial identification, DNA testing and record keeping, smart card usage, telephone records, e-mail monitoring, and the like, intrude themselves into our private lives on an ever-expanding basis. It seems that every company and every governmental agency has an interest in knowing what we do, what we like and dislike, what we read, how long we sustain interest in something, which stores we frequent, and what we ignore. the European Union (EU) and other countries outside the EU are taking an approach to privacy that companies with an international presence must address to maintain compliance with that approach.     

“Electric” Zip Tips™, Preliminary Results

Induction based fluidics (IBF), a new, simple patented approach for transporting liquids in the micro and the macro world, is discussed. Electric fields are shown to energize liquid/s in a container/s to execute an array of purposes. IBF is shown uniquely to energize N liquids in simple off the shelf devices, inductively. We discuss calibration and other issues, as we demonstrate how simple devices can dispense nanoliters and microliters with high precision and accuracy. Furthermore, we show preliminary single and eight channel data for the Zip Tip™ made by Millipore where the device transports liquids “electrically.” We briefly consider how such new devices, “electric” Zip Tips™, might automate desalting and the placement of digests for MALDI TOF analysis.     

Numerically optimized hard pulse sequences for fast frequency selective excitation and inversion

Numerically optimized hard pulse sequences were developed providing a frequency selective response of the transverse and longitudinal magnetization for several applicationsin vivo. The sequences are based on pulse trains with binomial ratios of the pulse angles and constant time intervals between the pulses. These pulse trains were systematically optimized to obtain broad Larmor frequency ranges in which the magnetization is not markedly influenced by the pulse sequence. In addition, the sequences had to provide maximum transverse magnetization or complete inversion of the magnetization beside the suppression range. Such behaviour is needed for chemical shift selective imaging, pulsed magnetization transfer, and frequency selective spectroscopyin vivo. The phase of the magnetization response is shown and adequate rephasing conditions are discussed as well as the actual phase duration. Short optimized hard pulse sequences for water and fat-selective imaging provide lowT ₂-sensitivity of the resulting magnetization. The new optimized hard pulse sequences are suitable, if optimum suppression of signals at one single point in the Larmor frequency spectrum is less important than good suppression in a larger frequency range.     

On numerical cubatures of nearly singular surface integrals arising in BEM collocation

In this paper we present efficient methods to approximate nearly singular surface integrals arising massively when discretizing boundary integral equations via the collocation method. The idea is to introduce local polar coordinates centred at a corner of the triangle. Thus it is possible to perform the inner integration analytically, where either the corresponding formulae can be evaluated numerically stable or can be replaced by simple (rational) approximation quite efficiently. We show that the outer integration can be performed by simple Gauß-Legendre quadrature and how to adapt the order of the Gauß formulae to a required order of consistency. Numerical tests will emphasize the efficiency of our method.     

Preliminary characterization of glial-secreted factors responsible for the induction of high electrical resistances across endothelial monolayers in a blood-brain barrier model

Low levels of sex hormone-binding globulin (SHBG) are considered to be an indirect index of hyperinsulinemia, predicting the later onset of diabetes mellitus type 2. In the insulin resistance state and in the presence of an increased pancreatic beta-cell demand (e.g. obesity) both absolute and relative increases in proinsulin secretion occur. In the present study we investigated the correlation between SHBG and pancreatic beta-cell secretion in men with different body compositions. Eighteen young men (30.0 +/- 2.4 years) with normal glucose tolerance and body mass indexes (BMI) ranging from 22.6 to 43.2 kg/m2 were submitted to an oral glucose tolerance test (75 g) and baseline and 120-min blood samples were used to determine insulin, proinsulin and C-peptide by specific immunoassays. Baseline SHBG values were significantly correlated with baseline insulin (r = -0.58, P < 0.05), proinsulin (r = -0.47, P < 0.05), C-peptide (r = -0.55, P < 0.05) and also with proinsulin at 120 min after glucose load (r = -0.58, P < 0.05). Stepwise regression analysis revealed that proinsulin values at 120 min were the strongest predictor of SHBG (r = -0.58, P < 0.05). When subjects were divided into obese (BMI > 28 kg/m2, N = 8) and nonobese (BMI < or = 25 kg/m2, N = 10) groups, significantly lower levels of SHBG were found in the obese subjects. The obese group had significantly higher baseline proinsulin, C-peptide and 120-min proinsulin and insulin levels. For the first time using a specific assay for insulin determination, a strong inverse correlation between insulinemia and SHBG levels was confirmed. The finding of a strong negative correlation between SHBG levels and pancreatic beta-cell secretion, mainly for the 120-min post-glucose load proinsulin levels, reinforces the concept that low SHBG levels are a suitable marker of increased pancreatic beta-cell demand.