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Taking its cue from the combination of life-size and miniature re-enactment that takes place in living history settings, this paper explores human play with scale, focusing in particular on what happens when historical and fantasy figures are made to dwell in miniature landscapes. I discuss relations between modellers and the miniatures that they display in dioramas or manipulate in war games, drawing on multi-sited fieldwork leading up to a small-scale exhibition I organised in Aberdeen in 2008. Taking issue with a discourse of disenchantment in modernity, which has led to a renewed interest in embodied human presence in a material world, I argue that the pleasure that modellers derive from miniature landscaping is a quintessentially contemporary pleasure that owes as much to contact and immersion in materials as to a distancing and abstracting from the miniature terrain through different forms of measurement and layers of representation. This interplay between closeness and distance is brought into sharper focus through discussion with an artist who has made playful use of railway modelling materials in his artwork. [ABSTRACT FROM PUBLISHER]

Abstract: MFCs are becoming a stronger contender in the area of alternative energy sources and show great promise in utilising a wide variety of organic sources. This paper describes the utilisation of neat undiluted urine as the main feedstock for different types of individual MFCs and stacks of small-scale MFCs, for direct electricity production, with conversion efficiencies of >50%. The smallest MFC (1.4 mL total volume) produced equal amounts of power to that produced by larger MFCs (6.25 mL), resulting in increased power densities. Power densities of 4.93 mW/m2 (absolute power of 1.5 mW) were recorded when 48 small-scale MFCs were connected as a stack and fed with urine. This study demonstrates the feasibility of using urine as an untreated fuel and that improved power outputs can be achieved through MFC miniaturisation and multiplication into stacks. [Copyright &y& Elsevier]

Documenting instances of model-rendering amongst the Gurung communities of central Nepal (and, also, now in London), the article considers issues relating to information-transfer in non-/subliterate and past archaeological circumstances. It variously reflects upon ‘play’, craft reproduction and the limitations of memory, as well as scientific/technological representation and, particularly, Himalayan modes of ritual substitution. [ABSTRACT FROM PUBLISHER]

Abstract: A new design of miniaturised free flow electrophoresis device has been produced. The design contains a separation chamber that is 45mm long by 31.7mm wide with a depth of 50μm and has nine inlet and nine outlet holes to allow for fraction collection. The devices were formed of polystyrene with carbon fibre loaded polystyrene drive electrodes and produced using injection moulding. This means that the devices are low cost and can potentially be mass produced. The devices were used for free flow isotachophoresis (FFITP), a technique that can be used for focussing and concentrating analytes contained within complex sample matrices. The operation of the devices was demonstrated by performing separations of dyes and bacterial samples. Analysis of the output from FFITP separations of samples containing the bacterium Erwinia herbicola, a biological pathogen, by cell culturing and counting showed that fractionation of the output was achieved. [Copyright &y& Elsevier]

Abstract: Micromachined Joule-Thomson (JT) coolers can be used for cooling small electronic devices. For this application, two types of micromachined JT cold stages with dimensions of 60.0 × 10.0 × 0.7 mm3 were developed and tested that were designed for operation with nitrogen at 100 K. A theoretical analysis is developed to investigate the application of these cold stages in the temperature range 80–250 K. This analysis shows that the cold stages can be operated with various working fluids. Experiments of both JT cold stages operating with nitrogen and methane as working fluids were done to validate this analysis. The cooling power and the temperature profile along the length of the counter-flow heat exchanger were measured. In this paper, the theoretical analysis is described and the measuring results are presented and discussed. [Copyright &y& Elsevier]

Abstract: Contamination of drinking water with the protozoan pathogen, Cryptosporidium, represents a serious risk to human health due to the low infectious dose and the resistance of this parasite to chlorine disinfection. Therefore, several countries have legislated for the frequent monitoring of drinking water for Cryptosporidium presence. Existing approved monitoring protocols are however time-consuming and do not provide essential information on the species, virulence or viability of detected oocysts. Rapid, more information-rich and automatable systems for Cryptosporidium detection are highly sought-after, and numerous miniaturised devices have been developed to address this need. This review article aims to summarise the state-of-the-art and compare the performance of these systems in terms of detection limit, ability to determine species, viability and performance in the presence of interferents. Finally, conclusions are drawn with regard to the most promising methods and directions of future research. [Copyright &y& Elsevier]

Abstract: Sample preparation procedures in use in many application areas are still tedious and manually intensive protocols. These characteristics mean that sample treatment is considered the most time-consuming and error-prone part of the analytical scheme. The increasing demand for faster, more cost-effective and environmental friendly analytical methods is a major incentive to improve these conventional procedures and has spurred research in this field during the last decades. This review provides an overview of the most relevant developments and successful approaches proposed in recent years concerning sample preparation. The current state-of-the-art is discussed on the basis of examples selected from representative application areas and involving conventional instrumental techniques for the final determination of the target compounds. Emphasis will be on those techniques and approaches that have already demonstrated their practicality by the analysis of real-life samples, and in particular on those dealing with the determination of minor organic components. The potential of the latest developments in this field for sample treatment simplification and complete hyphenation and integration of analytical process is discussed and the most pressing remaining limitations evaluated. [Copyright &y& Elsevier]

Abstract: In miniaturized objects fabricated by modern technology the smallest linear size may be of a few nanometers. In the field of microelectronics, the advantages of such a miniaturization are huge (increased complexity and reliability, reduced costs). The technology is now approaching the limits where further size reduction will be impossible, except for very novel techniques such as molecular electronics. Miniaturization research has also led to the discovery of nanometric objects such as carbon nanotubes, which turn out to be particularly appropriate for inventing new materials. Miniaturization techniques have been progressively applied in other fields, with the hope of obtaining improvements similar to those encountered in microelectronics. Examples are biochips, which concentrate on a few cm2 the recognition of ADN sequences, or ‘lab-on-a-chip’ devices, each of which constitutes a whole laboratory of chemical analysis, or MEMs (Micro Electro Mechanical Systems). New therapies will use miniaturized objects with multiple functions: For instance a nanoparticle can both recognize the target organ thanks to an appropriate protein, and deliver the therapeutic molecule to this target. These results have only been possible through new observation instruments, able to observe and manipulate nano objects. Is the observed evolution really a revolution of science and techniques? This is a point discussed in the conclusion, which also deals with risks associated to nanotechnologies, while the need for a social regulation is stressed. [Copyright &y& Elsevier]

Abstract: Several procedures are available for simulating and optimising separations in ion chromatography (IC), based on the application of retention models to an extensive database of analyte retention times on a wide range of columns. These procedures are subject to errors arising from batch-to-batch variability in the synthesis of stationary phases, or when using a column having a different diameter to that used when the database was acquired originally. Approaches are described in which the retention database can be recalibrated to accommodate changes in the stationary phase (ion-exchange selectivity coefficient and ion-exchange capacity) or in the column diameter which lead to changes in phase ratio. The entire database can be recalibrated for all analytes on a particular column by performing three isocratic separations with two analyte ions. The retention data so obtained are then used to derive a “porting” equation which is employed to generate the required simulated separation. Accurate prediction of retention times is demonstrated for both anions and cations on 2mm and 0.4mm diameter columns under elution conditions which consist of up to five sequential isocratic or linear gradient elution steps. The proposed approach gives average errors in retention time prediction of less than 3% and the correlation coefficient was 0.9849 between predicted and observed retention times for 344 data points comprising 33 anionic or cationic analytes, 5 column internal diameters and 8 complex elution profiles. [Copyright &y& Elsevier]

Abstract: The effects of the fluid friction acting on the endfaces of the revolving vane (RV) machine, where the cylinder rotates together with the rotor, are investigated analytically with closed form solutions. It was found that the endface losses of the RV machine are generally affected by both the relative velocity and the eccentricity between the rotor and the cylinder. The endface loss of an RV machine with the simply supported bearing arrangement is found to be always lower than that with the cantilever arrangement. When compared to a similar rotary machine but with a stationary cylinder, the RV machine used in this study exhibits a 95% decrease in the endface loss, while in the wider practical dimensions range, an RV machine consistently shows at least a 50% lower in endface loss. These findings supply more proof to the claim of the suitability of the employment of the RV mechanism in high-speed and high-pressure applications. [Copyright &y& Elsevier]

Abstract: A novel miniaturization technology for binary-fluid heat and mass exchange was developed and numerous components were fabricated for demonstration as different parts of an ammonia/water absorption heat pump. Short lengths of microchannel tubes are placed in an array, with several such arrays stacked vertically. The ammonia/water solution flows in falling film/droplet mode on the outside of the tubes while coupling fluid flows through the microchannels. Coupling fluid heat transfer coefficients are extremely high due to the use of microchannel tubes. Effective vapor–solution contact on the absorption side minimizes heat and mass transfer resistances. This concept addresses all the requirements for absorber design in an extremely compact geometry. The technology is suitable for almost all absorption heat pump components (absorbers, desorbers, condensers, rectifiers, and evaporators) and for a wide range of binary-fluid processes. The development of several components for absorption and desorption at different capacities using this technology is reported here. [Copyright &y& Elsevier]

Abstract: This paper presents the results of an experimentally validated model for the prediction of local heat and mass transfer rates in a microchannel ammonia–water desorber. The desorber is an extremely compact 178mm×178mm×0.508m tall component capable of transferring the required heat load (∼17.5kW) for a residential heat pump system. The model predicts temperature, concentration and mass flow rate profiles through the desorber, as well as the effective wetted area of the heat transfer surface. Previous experimental and analytical research by the authors demonstrated the performance of this same microchannel geometry as an absorber. Together, these studies show that this compact geometry is suitable for all components in an absorption heat pump, which would enable the increased use of absorption technology in the small-capacity heat pump market. [Copyright &y& Elsevier]

In this article, by replacing the series quarter-wavelength connecting line of conventional open-stub bandstop filter (BSF) with the equivalent P-shaped line, a compact dual-band BSF is proposed and designed. Furthermore, it suppresses a lot of spurious passbands of the open-stub BSF. Design equations of P-shaped line are achieved by ABCD matrixes. To validate the design concept, two full-wave electromagnetic simulators are used and the proposed filter is fabricated. The simulate results are in excellent agreement with measurement results. The circuit area of the dual-band BSF is only 50% of the conventional open-stub BSF. [ABSTRACT FROM AUTHOR]

The application of miniaturised separation techniques such as capillary LC, nano LC or capillary electrophoresis offers a number of advantages in terms of analytical performance, solvent consumption and the ability to analyse very small sample amounts. These features make them attractive for various bioanalytical tasks, in particular those related to the analysis of proteins and peptides. The skillful combination of such techniques with inductively coupled plasma mass spectrometry (ICP-MS) has recently permitted the design of combined analytical approaches utilising either elemental or molecule-specific detection techniques such as electrospray ionisation (ESI) or matrix-assisted laser desorption/ionisation (MALDI) mass spectrometry in a highly complementary manner for, as an example, proteomics-orientated research (heteroatom-tagged proteomics). Such hybrid approaches are, in particular, providing promising new options for the fast screening of complex samples for specific metal-containing or-more generally speaking-heteroatom-containing biomolecules, as well as the accurate absolute quantification of biomolecules, which is still an unsolved problem in bioanalysis. Here, progress in as well as the potential and the special requirements of hyphenating miniaturised separation techniques with ICP-MS are reviewed and critically discussed. In addition, selected applications are highlighted to indicate current and possible future trends within this emerging area of research. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Abstract: This study reports on a quantitative study of the influence of the most important geometrical design parameters for micro-machined flow distributors with uniform cross-section and filled with diamond-shaped pillars having their longest dimension oriented perpendicular to the axial flow direction. It was found that the shape of the bands eluting from the distributor improves with increasing aspect ratio (AR) of the pillars, both in terms of global warp and local axial dispersion. Increasing the AR from 5 to 25 reduces the distributor length needed to bring the maximal transversal velocity difference below 5% from 170μm to 15μm when using pillars with axial width of 5μm. To solve the problem that high AR pillar distributors only have a limited number of exit points, and therefore produce bands with a strong local warp, one can conceive mixed size distributors, wherein a zone filled with several rows of very high AR pillars is followed by one or more zones consisting of pillars with a smaller AR. With such a design, the variance of the eluting bands can be reduced to only 30% of the variance of a single size distributor. [ABSTRACT FROM AUTHOR]

Abstract: In this work the implementation of a histamine ion-selective electrode for fish freshness control is described. The solid-contact electrode is based on a polymeric membrane incorporating, respectively, α-cyclodextrin as an ionophore, 2-fluorophenyl 2-nitrophenyl ether as a plasticiser and potassium tetrakis(p-chlorophenyl) borate as an ionic additive. The conventionally shaped histamine electrode responded to histamine cation in the pH operational range of 3.5–5.5 with a slope of 31.7±1.3mVdec−1, and with a practical detection limit of (1.6±0.2)×10−6 molL−1. The miniaturisation of the above-described electrode enabled its use as a detector in a sequential-injection lab-on-valve system, yet with a useful lifetime shortened from 10months to approximately 1month under continuous operation. The optimised flow conditions were achieved for sample injection volumes of 70μL propelled towards the detection cell at the flow-rate of 12μLs−1 during 20s followed by a flow-rate of 15μLs−1 during 50s. The potentiometric analysis of histamine in different kinds of fish furnished results similar to those provided by the chromatographic method. The low cost of the analysis, the speed of the method and the use of a smaller volume and non pollutant reagents justify the use of potentiometry as an alternative analytical technique for this food control. [Copyright &y& Elsevier]

Abstract: Thoracic structures of the extremely small first instar larva of the strepsipteran species Mengenilla chobauti (ca. 200μm) were examined, described and reconstructed 3-dimensionally. The focus is on the skeletomuscular system. The characters were compared to conditions found in other insect larvae of very small (Ptiliidae) or large (Dytiscus) size (both Coleoptera) and features of “triungulin” larvae, first instar larvae of Rhipiphoridae, Meloidae (both Coleoptera), and Mantispidae (Neuroptera). The specific lifestyle and the extreme degree of miniaturisation result in numerous thoracic modifications. Many sclerites of the exo- and endoskeleton are reduced. Cervical sclerites, pleural ridges, furcae and spinae are absent. Most of the longitudinal muscles are connected within the thorax, and a pair of ventral longitudinal muscles is present in the pleural region of the meso- and metathorax. This results in a high intersegmental flexibility. Due to the size reduction and the correlated shift of the brain to the thorax, with 94 identified muscles the thoracic musculature appears highly compact. Compared to larger larvae the number of both the individual muscles and the muscle bundles are distinctly reduced. The thorax of the first instar larvae displays many additional strepsipteran autapomorphies. At least partly due to the highly specialised condition, potential synapomorphies with other groups were not found. [Copyright &y& Elsevier]

Abstract: A new methodology is proposed for monitoring 16 priority polycyclic aromatic hydrocarbons, using tree leaves as passive samplers, by means of a mini-ultrasonic probe coupled with reversed-phase liquid chromatography (RP-LC) and fluorescence (FL) detection. Separation and detection of the 16 PAHs were completed in 19min, using a 3μm (particle size) C18 column RP-LC with acetonitrile–water gradient elution. The ultrasonic probe device used was equipped with a 2mm titanium tip, and sample and solvent amounts used were just 50mg and 1mL, respectively. Multivariate optimisation of the variables affecting extraction was conducted by means of full factorial analysis to determine which of the variables were significant. A central composite design was applied to define surface responses and to calculate optimal values for the variables. The accuracy of the method was determined by both analysis of a Certified Reference Material with a similar matrix (IAEA-140 OC, seaweed) and by comparison of the results obtained with those from a previously developed method. The proposed analytical method avoids some of the main problems encountered in the determination of PAH in complex matrices; no clean-up step is necessary, consequently sample preparation time and costs can be significantly reduced. The developed method was applied to determine PAH in leaf samples from medlar and red and white mangrove trees, situated near PAH pollution sources. [Copyright &y& Elsevier]

Experimental and theoretical research on the wire flat rolling process as well as plane strain compression tests have proven that the rolling of small and thin strip out of wire is affected by size effects on yielding due to a changing ratio of grain size to characteristic specimen dimension and by size effects on friction due to the changing share of open lubricant pockets. These size effects have to be taken into account for future optimisation of the wire flat rolling process deployed for the manufacturing of microstrip. [ABSTRACT FROM AUTHOR]

A miniaturised implantable antenna with dual‐band operation the Medical Implant Communications Service (MICS) (402–405 MHz) and Industrial, Scientific, and Medical (ISM) (2400.0–2483.5 MHz) bands is presented. The size of the proposed antenna is 31.5 mm3 (8.75 mm × 7.2 mm × 0.5 mm) which is the smallest size compared to previous implantable antennas. A serpentine‐shaped radiating patch and open‐end slot placed on the ground plane are used for miniaturisation. The performance of the antenna was evaluated from measurements and is based on good agreement with simulations. [ABSTRACT FROM AUTHOR]

Abstract: Current results will be presented on developing and miniaturising a novel laser-assisted forming process to manufacture microstructures in metals such as stainless steel and aluminum. Due to its mechanical and optical properties, sapphire is a well-suited material for the micro-forming tool. Because of its high band gap, radiation with small wavelengths in the UV range is required to reach the ablation threshold. Thus, excimer lasers are used for manufacturing the microstructures. On the other hand, its high transmittance for higher wavelengths allows heating of the work-piece through the sapphire die during the micro-forming process, which allows a better form filling. The main goal of these investigations is to identify the scaling effects on micro-formed structures that result from miniaturising microstructures on dies for the development of strategies to overcome obstacles caused by these miniaturisation effects. [Copyright &y& Elsevier]

A miniaturised pressurised liquid technique has been applied to the extraction of volatile compounds present in oak wood samples used in making wine. The solvent extraction performed at high pressure and temperature has allowed the detection of a large number of compounds some of which present sensory and antioxidant properties. The effect of the main process variables on the efficiency of extraction has been studied: the composition of the extracted fraction depended mainly on the polarity of the solvent and the extraction temperature had a high influence on the extracted amount, while the effect of static extraction time and pressure were almost negligible. The highest recoveries were obtained for dichloromethane, for two static 10-min extraction cycles at 60 °C. Among the solvent extraction techniques, miniaturised pressurised liquid extraction presents several advantages, such as the use of reduced amounts of both sample and solvent and high extraction efficiency. [ABSTRACT FROM AUTHOR]

The use of malonic acid as a complexing agent has enabled a new method to be devised to allow the determination of magnesium to be made using miniaturised isotachophoresis. Using a leading electrolyte of 10 mmol L−1 caesium hydroxide and 2 mmol L−1 malonic acid at pH 5.1 gave the method a high specificity towards magnesium. Investigations using a poly(methyl methacrylate) chip device with an integrated conductivity detector showed that no interference from calcium, strontium, barium and sodium should occur. The method was found to be linear over the range of magnesium concentrations from 0.625 to 75 mg L−1 and the limit of detection was calculated to be 0.45 mg L−1. Separations were demonstrated with water samples but the procedure should also be applicable to more complex sample matrices such as inorganic explosive residues, blood or urine. [ABSTRACT FROM AUTHOR]

Abstract: We present the first morphological study of larvae and adults of Mikado sp. – one of the smallest known beetles and free-living insects (body length of adult is 390–455μm). Morphological and developmental consequences of miniaturisation in Mikado and insects in general are discussed. We used histological sectioning, scanning electron microscopy, laser confocal microscopy and 3D-computer reconstruction. For the first time we report that according to the morphometric data of Mikado sp., at least some ptiliid beetles have three larval stages. We studied the muscular system of adults and larval stages. It is shown that ptiliid beetles have nearly the complete set of muscles found in larger staphyliniform beetles. Developmental and size dependent changes in the relative volume of different organs are addressed. All organ systems change allometrically in the development of Mikado sp. as well as in comparison with larger representatives of Ptiliidae and closely related groups of beetles, such as Staphylinidae. We conclude that the factors limiting miniaturisation are the size of the neural system, associated with the number and size of neurons, the mass of the skeleton, the egg size (free-living insects), and consequently the volume of the reproductive system. [Copyright &y& Elsevier]

Herein, we summarize the current status of native fluorescence detection in microchannel electrophoresis, with a strong focus on chip-based systems. Fluorescence detection is a powerful technique with unsurpassed sensitivity down to the single-molecule level. Accordingly fluorescence detection is attractive in combination with miniaturised separation techniques. A drawback is, however, the need to derivatize most analytes prior to analysis. This can often be circumvented by utilising excitation light in the UV spectral range in order to excite intrinsic fluorescence. As sensitive absorbance detection is challenging in chip-based systems, deep-UV fluorescence detection is currently one of the most general optical detection techniques in microchip electrophoresis, which is especially attractive for the detection of unlabelled proteins. This review gives an overview of research on native fluorescence detection in capillary (CE) and microchip electrophoresis (MCE) between 1998 and 2008. It discusses material aspects of native fluorescence detection and the instrumentation used, with particular focus on the detector design. Newer developments, featured techniques, and their prospects in the future are also included. In the last section, applications in bioanalysis, drug determination, and environmental analysis are reviewed with regard to limits of detection. [ABSTRACT FROM AUTHOR]

Micro Manufacturing is the production of small components and products, which have not been possible until the recent introduction of ground breaking technologies and techniques in the traditional manufacturing processes. This comprises the manufacture of parts in the micrometer and manometer ranges. This exciting emerging niche, allowing miniaturisation of components particularly in the consumer electronics, medical, pharmaceutical, automotive, aerospace, jewellery, micro optics and defence markets, is now available in all the major traditional groups of manufacturing processes (Macro Manufacturing), providing the production of micro-scale parts. Micro-and Nano Manufacturing Technologies (MNT) make use of a variety of materials, components and knowledge-based technologies providing functionality and intelligence to highly miniaturised systems. This paper presents an updated overview of these emerging manufacturing technologies. [ABSTRACT FROM AUTHOR]

Considered are problems of Micro Air Vehicles (MAV) miniaturization via evolutionary way for the fixed flight task (flight velocity, flight time, range etc.). Peculiarities of aerodynamics, strength, powerplants, and electronic components were analyzed. On the basis of results obtained the main recommendations for scaling of components and aircraft as whole were formulated: frequency of propeller rotation must be increased proportionally the dimensions decrease, magnetic field of electric drive must be increased as square root of dimensions decrease, total mass must be decreased as square of dimensions decrease. For the proportionality of dimensions the accumulator's energy density must be increased proportionally the dimensions decrease. For the scaled model the same materials can be used as for original one. Some extra methods of mass and size decrease have been proposed. Results obtained were verified on two tests Micro Air Vehicles. Flight experiments with these MAVs show that there exists good correlation between the analytical and experimental results. [ABSTRACT FROM AUTHOR]

Abstract: A new method has been developed to allow the determination of the chlorate, chloride and perchlorate anions in inorganic explosive residues to be made using isotachophoresis (ITP). To enable a good separation of these species to be achieved the method involves the use of two complexing agents. Indium(III) is used to allow the determination of chloride whilst using nitrate as the leading ion and α-cyclodextrin is used to allow the separation of chlorate and perchlorate. Separations were carried out using a miniaturised poly(methyl methacrylate) (PMMA) separation device. The method was applied to analysing both model samples and actual inorganic explosive containing residue samples. Successful determinations of these samples were achieved with no interference from other anions typically found in inorganic explosive residues. Limits of detection (LOD) for the species of interest were calculated to be 0.80mgl−1 for chloride, 1.75mgl−1 for chlorate and 1.40mgl−1 for perchlorate. [Copyright &y& Elsevier]

Abstract: The paper presents a new concept of micro-artefact, the fiber gauge, consisting of a set of optical fibers sticking out from a flat surface. The fibers are arranged as a regular array of different height cylinders, with aspect ratios up to 20:1. The artefact is produced taking advantage of optical fibers manufacturing technology, featuring relatively high geometrical accuracy, combined with very good mechanical properties. The fiber gauge can be applied to calibration of most contact or non-contact instruments for characterization of surface topographies and 3D micro-geometries, such as micro- or nano-CMMs, optical instruments, etc. Different designs and dimensions allow for realization of structures that can be adapted to various instruments calibration needs. Development, analysis and application of prototype artefacts are reported. [Copyright &y& Elsevier]

The aim of this investigation was to develop a specific modelling approach capable of reducing the size of the fuel injector solenoid device while improving its response time and attraction force. Several developed modelling and simulation procedures have focused on various aspects of solenoid component modifications in order to develop an evolution process of miniaturising a fuel injector solenoid, using the latest finite element method (FEM) tool software. The specific factors that influenced the optimum operation of the fuel injector solenoid were the geometrical shape of individual solenoid components, material properties, air-gap constraints, boundary conditions, current source conditions, mass constants, and damping coefficients of the plunger. The attraction force distribution in the main air-gap was directly influenced by the taper angle of the 2D and 3D plunger pole faces, plunger length and the permanent magnetism. The precise definition of the electro-mechanical motion of plunger was of enormous importance in reducing the fuel injector solenoid response time, closely related to stroke and mass of the plunger, spring characteristics, motion and rebound of the plunger. Using the developed approach, the initial size of the fuel injector has been reduced by 35%, the attraction force increased by 26% and the response time reduced by 76%. However, by frequently repeating the design trials and conducting a thorough experimental investigation, the final minimum response time was achieved by the virtual rebound delay model. The reduction in response time from the 'optimal' experimental to virtual model was by 35%. The simplicity and effectiveness of the developed methods, allowed for quick and accurate evaluation. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents the findings of a feasibility study investigating the behaviour of DNA under conditions of miniaturised isotachophoresis. An electrolyte system comprising a leading electrolyte of 5mM perchloric acid at pH 6.0 and a terminating electrolyte of 10mM gallic acid was devised and used to perform isotachophoresis of DNA containing samples on a miniaturised poly(methyl methacrylate) device. Under such conditions it was found that no separation of DNA fragments was observed with the substance migrating instead as a single isotachophoretic zone. Whilst such a result shows the method is unsuitable for analysis DNA it offers significant potential as a means of sample preparation for subsequent analysis using another method. This is because the single zone of DNA formed is preconcentrated to a constant concentration governed by the leading ion and is separated from all species with different effective electrophoretic mobilities. [Copyright &y& Elsevier]

Abstract: An injection moulded free flow isotachophoresis (FFITP) microdevice with integrated carbon fibre loaded electrodes with a separation chamber of 36.4mm wide, 28.7mm long and 100μm deep is presented. The microdevice was completely fabricated by injection moulding in carbon fibre loaded polystyrene for the electrodes and crystal polystyrene for the remainder of the chip and was bonded together using ultrasonic welding. Two injection moulded electrode designs were compared, one with the electrode surface level with the separation chamber and one with a recessed electrode. Separations of two anionic dyes, 0.2mM each of amaranth and acid green and separations of 0.2mM each of amaranth, bromophenol blue and glutamate were performed on the microdevice. Flow rates of 1.25mlmin−1 for the leading and terminating electrolytes were used and a flow rate of 0.63mlmin−1 for the sample. Electric fields of up to 370Vcm−1 were applied across the separation chamber. Joule heating was not found to be significant although out-gassing was observed at drive currents greater than 3mA. [Copyright &y& Elsevier]

Abstract: Thermoacoustic refrigerators have been developed during the last 15 years, employing quasi-standing resonant acoustic waves inside fluid-filled cavities to transfer heat along a stack region. Because higher efficiency can be reached when a significant travelling wave component exists in the resonator, specific resonant thermoacoustic devices have been designed allowing to adjust more or less the ratio of travelling and standing wave components. However, the acoustic pressure field and the particle velocity field do not appear to be the optimal ones, for the thermal quantities of interest. Thus, it is the aim of the paper to present a new kind of thermoacoustic standing wave-like device which allows to control easily and independently the pressure field and the particle velocity field, after investigating the optimal acoustic field, in the stack region, for the main parameters of interest, i.e. the temperature gradient, the thermoacoustic heat flow and the coefficient of performance. [Copyright &y& Elsevier]

This work explores the building of superconducting left-handed transmission lines (LH-TL) for microwave applications. Low-loss, via-free and miniature LH-TLs are demonstrated on HTS thin film devices. LH-TLs with asymmetrically arranged shunt inductors are discussed. The effects of using bonding-wires to balance the coplanar ground planes are observed. A second configuration of LH-TL with a further miniaturised structure is designed and measured. It shows the capability of enhancing the left-handed bandwidth. [ABSTRACT FROM AUTHOR]

Abstract: Enhanced sensitivity is a well known benefit of miniaturised LC–electrospray (ESI)–MS/MS methods. The suitability of miniaturised LC–MS/MS for quantification of small molecules in dialysates was investigated using the anti-epileptic drug oxcarbazepine, its active metabolite, 10,11-dihydro-10-hydroxycarbamazepine, and the internal standard for microdialysis probe calibration, 2-methyl-5H-dibenz(b,f)azepine-5-carboxamide, as test compounds. ESI–MS detection is sensitive to matrix effects. Therefore, dialysate matrix effects were investigated by comparing the responses of standards made in water, Ringer''s solution (salt solution used as perfusion fluid) and blank dialysate matrix. Due to the occurrence of ion suppression or enhancement, direct injection of dialysis samples onto the analytical column could not be applied for quantification of small molecules in dialysis samples. Column switching was necessary for desalting and preconcentration of the dialysates. However, this approach was not able to completely eliminate salt effects when the injection volume exceeded 1μL. No differences in response between Ringer''s solution and dialysate matrix were detected at capillary and nano-dimensions. Calibration standards should be prepared with Ringer''s solution instead of water for quantitative analysis of microdialysates. A microbore, capillary and nano-LC–ESI–MS/MS method were compared in terms of method feasibility, linearity, sensitivity, accuracy and precision. Downscaling to capillary and nano-dimensions resulted in a gain in detection sensitivity of 5 and 50, respectively. Miniaturised LC–MS/MS was found to be fit for quantification of small molecules in dialysates with acceptable accuracy and method precision. [Copyright &y& Elsevier]

Abstract: Several analytical methods have been used to determine whether ligands bind to bovine β-lactoglobulin (βLG). The most common methods are based on fluorescence quenching. We have miniaturised this method from a quartz cell to a 96-well plate. The miniaturisation was evaluated using retinol. The binding constants between the two methods demonstrated a good correlation. The 96-well plate method is much faster and allows many references to be used in the same analysis. The miniaturised method was used to study the binding of three different ligands (4-HPR, arotinoid, warfarinyl palmitate) modelled to bind to βLG. The binding data showed that all of these ligands bound to βLG. The method was further used to demonstrate that reindeer βLG could also bind the four ligands in the same way as bovine βLG. Because one aim is to use bovine and reindeer βLG as a binder molecule for aliments in e.g. functional food or for drugs, the influence of pH was also studied and demonstrated that short-term acidic conditions had only a slight effect on the binding properties. [Copyright &y& Elsevier]

Abstract: Hepatocyte assays, routinely used to assess the metabolic stability of new chemical entities, were recently improved by using hepatocytes in suspension instead of primary cultures [N. Blanchard, L. Richert, B. Notter, F. Delobel, P. David, P. Coassolo, T. Lavé, Impact of serum on clearance predictions obtained from suspensions and primary cultures of rat hepatocytes, Eur. J. Pharm. Sci. 23 (2004) 189–199]. The aim of the present study was to investigate miniaturising the suspension assay by using cryopreserved human hepatocytes, i.e., 150,000cells/well in 96-well plates, to predict hepatic clearance (CLH) in order to increase compound throughput and decrease cost and tissue requirements. For this, an evaluation was first carried out with rat hepatocytes. Then, human hepatocytes from various donors were used under these predetermined conditions, either immediately after isolation, either after a 20-h-cold storage period in UW or after cryopreservation. The values of CLint and CLH determined using human hepatocytes in suspension in 96-well plates, immediately after isolation, after cold storage or after cryopreservation, were comparable to those obtained with hepatocytes in primary culture. In particular, the use of cryopreserved human hepatocytes in suspension in a 96-well format appeared to be largely satisfactory as a tool for screening and ranking of compounds in the early phase of the drug discovery process. [Copyright &y& Elsevier]

Abstract: A new design of miniaturised separation device for performing isotachophoresis (ITP) has been produced. The device contains a simple arrangement of channels comprising a single separation channel with a ‘double T’ injection geometry. The device was produced in poly(methyl methacrylate) and incorporates an on-column conductivity detector. A new electrolyte system was developed to enable the rapid determination of chloride to be made. This electrolyte system uses a leading ion of 3.5mM nitrate at pH 3.0 with 0.5mM indium(III) added as a complexing agent. Use of this electrolyte system with the new separation device allowed chloride samples to be analysed in under 100s, with a limit of detection (LOD) calculated to be 2.2mgl−1. [Copyright &y& Elsevier]

A new method allowing the simultaneous determination of arsenic(V), selenium(IV) and selenium(VI) using miniaturised isotachophoresis has been developed. The method uses 0.02 M nitric acid buffered to pH 5.5 with histidine as the leading electrolyte. Using a miniaturised poly(methyl methacrylate) chip device with an integrated conductivity detector, separations of model samples and an industrial process stream sample were achieved. Limits of detection were calculated to be 0.85 mg L−1 for arsenic(V), 0.95 mg L−1 for selenium(IV) and 1.0 mg L−1 for selenium(VI). A method for the analysis of arsenic(III), using a glycolic acid based leading electrolyte to eliminate carbonate interference is also presented. [ABSTRACT FROM AUTHOR]