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We fabricated arrays of cantilever sensors suspended deep inside fluid wells. To eliminate critical alignment and assembling steps during encapsulation of the cantilevers, these 3-D MEMS devices are realized in a single-side, single-wafer process by employing photolithography on bulk micromachined substrates. Silicon nitride cantilevers with varying geometries are suspended up to [email protected] below the wafer surface, and a structured gold layer is patterned on top. After calibrating the cantilevers in an optical lever setup, the formation of a DNA monolayer on the cantilever surface is detected.

In this paper a new contactless transport system for thin, flat products, such as silicon wafers, is introduced. The product is carried on a thin aerostatic film between the product and the transport system and transported along the system using viscous traction on the product surface. This viscous traction is the result of pressure driven air flow in an array of actuator cells. Several possible industrial applications are discussed, followed by an explanation of the operating principles. Furthermore an analytical model of the system is presented, together with computational results. Numerical modeling using FEA, solving for the incompressible Navier–Stokes equations, shows results that are in good agreement with the described analytical model and some experimental results. The maximum acceleration and vertical bearing stiffness that can be obtained for the considered actuator geometry meet the requirements for the considered industrial applications.

Summary Objective Delirium is a frequent and serious problem in the Intensive Care Unit (ICU). Several international guidelines recommend daily monitoring for ICU-delirium. The purpose of this article is to give an up-to-date overview of the current status of monitoring and treatment of ICU-delirium in the Netherlands. Design Nation-wide, telephone-based questionnaire survey. Participants Head nurse of all ICUs and a random sample of intensivists. Results Only 14% (n = 14) of all Dutch ICUs (n = 103) monitored for ICU-delirium. Of these, only half (7%) used a tool that is validated in ICU patients. In 31% of Dutch ICUs, a protocol was used to treat ICU-delirium. Responses were obtained from 100% of ICUs. Conclusion Despite an international guideline, not more than 7% of ICUs in our study routinely evaluated the presence of delirium with a validated instrument. Fewer than one-third of Dutch ICUs use a protocol to treat ICU-delirium.

A method is described to integrate particle filters inside a silicon wafer by creating pores in a recessed membrane. The filters are created in either a silicon or a silicon nitride membrane located 100@mm below the wafer surface. The fabrication process involves anisotropic etching of front- and back-side of a (100) silicon wafer, deposition of a silicon nitride layer, spraycoating of photoresist and reactive ion etching of the pores. The filters may serve as a well or reaction chamber at the same time. We have patterned pore diameters in the 10-50@mm range in 100@mm recessed membranes that are suitable for application in stacked systems such as in an integrated inkjet nozzle.

This paper presents GreyHound, a new methodology to improve cell placement of logic netlists in standard design flows by utilizing the regular structure of datapath circuitry. Key features of the methodology are automatic extraction of regular structures and utilization of regularity even after extensive logic optimization. The latter is important because logic optimization tends to introduce significant non-regularities even though the underlying structural regularity is largely preserved. In the proposed methodology, the structural regularity in the initial gate netlist produced by module generators is extracted automatically. This results in alignment specs for the regular logic, which are used to drive the subsequent placement of the netlist. After each customary iteration through placement and logic optimization, a logic correspondence extractor is used to identify functional correspondences between the optimized and the original netlist. Along these correspondences, the extracted structural alignment cell attributes are inherited from the initial to the optimized circuit so that its cells can be aligned accordingly.

In order to investigate the impact of plant physiology on emissions of biogenic volatile organic compounds monoterpene emission rates from Rosmarinus officinalis (L.) and Pistacia lentiscus (L.) and isoprene emission rates from Erica arborea (L.) and Myrtus communis (L.) were determined. The study, an activity in the framework of BEMA (Biogenic Emissions in the Mediterranean Area), was carried out in May 1994 at Castelporziano near Rome in Italy, using a dynamic enclosure technique combined with recording CO2 gas exchange, temperature and irradiance data. The monoterpenes dominating the emission pattern were 1,8-cineol, α-pinene and β-pinene for rosemary and α-pinene, linalool and β-pinene + sabinene for pistachio. Total monoterpene emission rates standardized to 30°C of 1.84 ± 0.24 and 0.35 ± 0.04 μg Cg−1 dw h−1 were found for rosemary and pistachio, respectively (on a leaf dry weight basis). Myrtle emitted 22.2 ± 4.9 μg C g−1 dw h−1 at standard conditions (30°C, PAR 1000 μmol photons m−2 s−1 as isoprene and erica 5.61 μg C g−1 dw h−1 The carbon loss due to terpenoid emissions per photosynthetically carbon uptake was about 0.01–0.1% for the monoterpene emitters. The isoprene emitting shrubs lost 0–0.9% of the assimilated carbon. The rapid induction of emissions in the sun after temporary shading indicates that isoprene emissions were closely linked to photosynthesis. A higher proportion of the assimilated carbon was lost as isoprene under conditions of high light and temperature compared to the morning and evening hours.

Experiments were carried out to characterize FEP (fluorinated ethylene-propylene copolymers) Teflon®bags as reactors for studies of photochemical reactions in sunlight of pollutants at low concentrations. Measurements of toluene loss, carbon monoxide oxidation and ozone formation in zero air in sun irradiated bags demonstrated a significant reactivity caused by the Teflon®film. The results indicate that such bags can be unsuitable for photochemical experiments at low (ppb) concentration levels.

For mechanisms to guide small rotations and translations in instruments the use of elastic elements, such as torsion wires, membranes and plate springs, is widely accepted. In general the loads, necessary to move the body guided by an elastic element to a desired position, contain components which cause undesired motions. To minimize motions in directions, other than the desired rotation or translation, large values of the stiffnesses in these directions are required. These stiffnesses involve a certain stiffness in the direction of the desired motion. If this stiffness is too large it is possible to decrease this stiffness to an acceptable value by fitting a mechanism with negative stiffness parallel to the elastic element. In this paper a mechanism with negative spring stiffness will be discussed of which the action is based on the instability of the second order buckling state of a flat plate spring clamped at both ends. The action of the negative “spring” is independent of gravity. Moreover, a special advantage is that the mechanism contains no sliding parts.