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Here, we investigate separately the dependence of the mixing time on the size and velocity of micro-droplets moving through serpentine channels. We find that the mixing time scales linearly with droplet size. All experimental data collapse on a master-line, when the convective time scale is multiplied by the dimensionless droplet size.

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 piezoelectric positioning systems the achievable bandwidth is often limited by weakly damped resonant modes. System performance may be improved by avoiding the excitation of these modes. If sufficient mechanical damping is present this can be done by shifting resonant modes towards anti-resonant modes through manipulation of the mechanical boundary conditions. In a second approach the anti-resonances may be shifted towards the resonances by the application of modal actuation. Using this method the excitation of the second and higher order modes can be avoided by adjusting the distribution of actuation forces. This paper investigates and compares the application of modal control techniques in systems that are based on piezoelectric tube actuators such as atomic force microscopes.

Weather Research and Forecasting (WRF) model predictions using different boundary layer schemes and horizontal grid spacings were compared with observational and numerical large-eddy simulation data for conditions corresponding to a dry atmospheric convective boundary layer (CBL) over the southern Great Plains (SGP). The first studied case exhibited a dryline passage during the simulation window, and the second studied case was used to examine the CBL in a post-cold-frontal environment. The model runs were conducted with three boundary layer parameterization schemes (Yonsei University, Mellor–Yamada–Janjić, and asymmetrical convective) commonly employed within the WRF model environment to represent effects of small-scale turbulent transport. A study domain was centered over the Atmospheric Radiation Measurement Program SGP site in Lamont, Oklahoma. Results show that near-surface flow and turbulence parameters are predicted reasonably well with all tested horizontal grid spacings (1, 2, and 4 km) and that value added through refining grid spacing was minimal at best for conditions considered in this study. In accord with this result, it was suggested that the 16-fold increase in computing overhead associated with changing from 4- to 1-km grid spacing was not justified. Therefore, only differences among schemes at 4-km spacing were presented in detail. WRF model predictions generally overestimated the contribution to turbulence generation by mechanical forcing over buoyancy forcing in both studied CBL cases. Nonlocal parameterization schemes were found to match observational data more closely than did the local scheme, although differences among the predictions with all three schemes were relatively small.

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.

Mastering high‐density optical disks, like the Blu‐ray™ disk, requires new equipment design. Active magnetic bearing technology seem well suitable for this purpose, but challenges arise in obtaining the required extreme accuracy. Creating a very low mechanical coupling between the system and the external world is the potential solution to this challenge pursued in this paper. Design considerations on actuators, amplifiers, sensors and overall design are discussed and the system performance is predicted using an error‐budgeting estimation. This prediction indicates the feasibility of the concept, while the first prototype has been assembled and is being tested.

The SeaCluse computer code calculates the nonlinear interactions between sea spray droplet concentrations and the scalar fields of water vapor concentration and temperature in the marine atmospheric surface layer. The code simulates most of the dynamics of the evaporating sea spray droplets in the turbulent air flow over a wavy surface, the thelmodynamic transformations of the spray droplets, and the influence of the droplets on the structure of the lower marine atmosphere. The main processor computes along the vertical the horizontally averaged budgets of droplet concentration, water vapor concentration, and sensible heat, including the dynamic and thermodynamic air-droplet interactions. This paper presents the first simulations of evaporating sea spray droplets made with the SeaCluse model. It is shown that common assumptions such as exponential vertical concentration profiles and the evaporation of all droplets to their equilibrium radius do not necessarily hold for droplets with a radius larger than ~30 µm. The present results also demonstrate the importance of the nonlinear interactions between sea spray droplets and the scalar fields of water vapor and temperature. Most droplets evaporate close to the surface, in a layer of ~2-3 times the wave height. The impact of evaporating sea spray droplets increases rapidly with increasing wind speed.

Checking the functional equivalence of sequential circuits is an important practical problem. Because general algorithms for solving this problem require a state-space traversal of the product machine, they are computationally expensive. In this paper, we present a new method for sequential equivalence checking which utilizes functionally equivalent signals to prove the equivalence of both circuits, thereby avoiding the state-space traversal. The effectiveness of the proposed method is confirmed by experimental results on retimed and optimized ISCAS'89 benchmarks.

An intercomparison experiment on preconcentration of monoterpenes from air samples was carried out by three European laboratories (Technische Universitat Munchen [TUM], Institut National Polytechnique de Toulouse [INP], Joint Research Center Isprs [JRC]) using Tenax porous polymer as an adsorbent. Sampling procedures, gas chromatographic analysis and standardisation methods differed in each laboratory and were compared in this study. Tenax adsorption tubes loaded with up to 10 monoterpenes (tricyclene, α-pinene, β-pinene, camphene, sabinene, myrcene, δ3-carene, p-cymene, 1,8-cineole and limonene) were created independently and exchanged for analysis between the working groups. For most monoterpenes the recoveries found by the different laboratories were 100%. The precision of analyses was better than 20%. Independent determinations of α-pinene mixing ratios in the air of the crown region in a natural spruce stand corresponded satisfactorily. Monoterpene emission rates of attached twigs in the sun...

Delirium is a frequent problem in the intensive care unit (ICU) associated with poor prognosis. Delirium in the ICU is underdiagnosed by nursing and medical staff. Several detection methods have been developed for use in ICU patients. The aim of this study was to compare the value of three detection methods (the Confusion Assessment Method for the ICU [CAM-ICU], the Intensive Care Delirium Screening Checklist [ICDSC] and the impression of the ICU physician with the diagnosis of a psychiatrist, neurologist, or geriatrician).Prospective study.During an 8-month period, 126 patients (mean age 62.4 years, sd 15.0; mean Acute Physiology and Chronic Health Evaluation II score 20.9, sd 7.5) admitted to a 32-bed mixed medical and surgical ICU were studied.The included patients were assessed independently by trained ICU nurses using either the CAM-ICU or the ICDSC. Furthermore, the ICU physician was asked whether a patient was delirious or not. A psychiatrist, geriatrician, or neurologist serving as reference rater diagnosed delirium using established criteria.The CAM-ICU showed superior sensitivity and negative predictive value (64% and 83%) compared with the ICDSC (43% and 75%). The ICDSC showed higher specificity and positive predictive value (95% and 82% vs. 88% and 72%). The sensitivity of the physicians view was only 29%.ICU physicians underdiagnose delirium in the ICU, which underlines the necessity of standard evaluation in all critically ill patients. In our mixed ICU population, the CAM-ICU had a higher sensitivity than the ICDSC.

Cumulus oocyte complexes (COCs) and cumulus oocyte complexes connected to a piece of the membrane granulosa (COCGs) were isolated from bovine antral follicles with a diameter of 2 to 8 mm. After culture of COCGs without gonadotrophic hormones for 22 hr approximately 50% of the oocytes were still in the germinal vesicle (GV) stage. Histology of the COCGs showed that the pieces of the membrana granulosa were free of thecal cells and parts of the basal membrane. This indicates that the membrana granulosa solely inhibits the progression of meiosis. To investigate the effect of gonadotropins on the resumption of meiosis of oocytes from small and medium sized antral follicles, COCs and COCGs were cultured with or without rec-hFSH or hCG. Addition of 0.05 IU rec-hFSH to the culture medium of COCGs resulted in germinal vesicle breakdown in 97.8% of the oocytes compared to 46% in the control group, and an increase of the diameter of the COCs (479 microns vs. 240 microns in the control group). Addition of 0.05 IU hCG to the culture medium had no effect on nuclear maturation (47.2% GV vs. 48.5% GV in the control group) nor on cumulus expansion (246 microns vs. 240 microns in the control group). RT-PCR on cDNA of the follicular wall, cumulus cells, granulosa cells, COCs, and oocytes revealed that mRNA for FSH receptor was present in all cell types except oocytes. mRNA of the LH receptor was detected exclusively in thecal cells. Nucleotide sequence analysis and alignment of the cloned PCR products showed the presence of two isoforms of the FSH receptor mRNA and two isoforms of the LH receptor mRNA. It is concluded that, in vitro, resumption of meiosis of oocytes, originating from small and medium sized antral follicles and meiotically arrested by the membrana granulosa, is triggered by FSH and not by LH. This is supported by the fact that receptors for FSH, but not for LH, are transcribed in the cumulus and granulosa cells of these follicles.

The performance assessment of electro-optical (EO) systems with propagation prediction codes requires accurate atmospheric models. The model that is most frequently used for the prediction of aerosols and their effect on extinction in the marine atmosphere is the U.S. Navy aerosol model (NAM) (Gathman, 1983). The NAM was developed for open ocean applications, where it works well. In coastal areas, however, the performance of the NAM may be reduced (Tanguy et al., 1991; De Leeuw, 1993). Based on an extensive series of measurements on the Irish Atlantic coast, an extension of the NAM for the coastal zone is proposed. As in the NAM, the dependence of the aerosol concentration on meteorological parameters is parameterized using empirical coefficients. The effect of the coastal zone is modeled as a function of fetch. A reasonable agreement is found between the model and the aerosol size distributions as measured on the island Inisheer, west of Galway Bay, Ireland.

A strain of the methylotrophic yeast Hansenula polymorpha, A16, has been developed that expresses the guar alpha-galactosidase gene to 22.4 mg/g dry cell weight in chemostat cultures at a dilution rate of 0.1 h(-1). This corresponds to more than 13.1% of soluble cell protein, of which 56-62% is secreted into the medium. The alpha-galactosidase gene was flanked by the promoter and terminator sequences of the H.polymorpha mox gene, which can direct expression of the mox gene itself more than 30% of total cell protein under methanol growth. The expression cassette (pUR3510) based on the Saccharomyces cerevisiae plasmid, YEp13, was integrated into the genome. Such transformants were stable in chemostat cultures and exhibited 100% stability for both alpha-galactosidase+ and leu+ phenotypes. Chemostat cultures produced higher levels of alpha-galactosidase with higher specific productivities expressed as mg alpha-galactosidase g(-1) h(-1) compared to batch cultures.

In methanol-utilizing yeasts, catalase is an essential enzyme for the destruction of hydrogen peroxide generated by methanol oxidase (E.C. 1.1.3.13). It was found however that a catalase-negative mutant of Hansenula polymorpha is able to consume methanol in the presence of glucose in continuous cultures. At a dilution rate of 0.1 h-1, stable continuous cultures could be obtained during growth on methanol/glucose mixtures with a molar ratio of methanol/glucose between 0 to 2.4. In these cultures methanol oxidase was induced up to a level of 40% of that obtained in the wild-type strain. The hydrogen peroxide-decomposition activity of the mutant was studied in more detail by pulsing methanol to samples of steady-state cultures. Only after the addition of excess methanol the hydrogen peroxide-decomposing system became saturated, and the cells excreted hydrogen peroxide. This was accompanied by excretion of formaldehyde and a rapid loss of viability. The presence of extracellular catalase during a methanol pulse prevented the loss of viability. The nature of the alternative hydrogen peroxide-decomposing enzyme system remains to be elucidated. Its capacity strongly depended on the cultivation conditions and pretreatment of the cells. Cells grown on formaldehyde/glucose mixtures showed a lower methanol tolerance than those grown on the methanol/glucose mixtures. Freeze-drying of cells drastically enhanced the excretion of hydrogen peroxide, probably as a result of an inactivation of the decomposing system.

The changes in cell wall strength of Hansenula polymorpha have been investigated in continuous cultures with respect to the recovery of methanol oxidase (MOX). Cultures grown on several substrate mixtures that enable induction of MOX have been compared with cultures grown on methanol as the sole inducer. The effects of dilution rate (D) on lysis properties have been studied. The cell wall strength was consistently influenced by growth media and D. Media containing glycerol/methanol showed the slowest lysis kinetics, with a large fraction of non-degradable cell wall material. In continuous cultures grown on a mixture of glucose and methanol both the resistance to zymolyase and the mean cell wall thickness increased at D 0.2 h−1, both protein and MOX release rates increase, reflecting a change in lysis mechanism due to the increased fraction of thin daughter cells. Kinetic analysis of zymolyase lysis using both physical and enzymatic methods provides information for achieving optimal recovery of MOX.

Many analyses of the depressed economy leave out of consideration the fact that many consumers and producers and probably also the government are now paralysed by fixation on the rationing they feel in their sales markets. Policies should be directed towards the destruction of the restrictions by which consumers', producers' and government behaviour is bounded. The increased attention since 1981 to an aggressive industry policy, specificly directed towards rein du strialization, and for the institutions required for designing and implementing such a policy, fit into the conviction that the current difficulties are due to market failures which prevent markets from generating and seminating the sufficiently accurate information required for efficiently allocating production factors.

At ambient temperatures, hydrogen chloride is a strong bactericide. At a partial hydrogen chloride pressure of 30 mm Hg, the number of spore-bearing colony forming units present in straw dust particles of 0–32 μm was reduced by a factor-of more than 50 000 within 60 s. Naked spores of Bacillus subtilis were reduced in viability by a factor of 100 000 within only 10 s. Viability of vegetative cells of various kinds of bacteria was reduced by a factor of more than 107 within 10 s. The method of administration of the gas influenced the sterilization and had to be adapted to the geometry of the surfaces to be sterilized. The smaller the dust particles, the better the sterilization, seemingly due to the lower degree of inhibition of diffusion of gas to the microorganisms enclosed in the particles. Increases in treatment time and concentration of hydrogen chloride enhanced the sterilizing effect to a lesser extent when large dust particles were involved. The partial water vapour pressure did not influence the sterilization between 0.3 and 6 mm Hg. An increase in temperature decreased the sterilizing effect.

Many of the potential technical applications of alcohol oxidase (MOX; EC 1.1.3.13) are limited by the presence of high activities of catalase in the enzyme preparations. In order to circumvent laborious and costly purification or inactivation procedures, the induction of MOX in a catalase-negative mutant of Hansenula polymorpha has been studied. Emphasis was laid on the induction of activities of MOX and the dissimilatory enzymes in continuous cultures grown on various mixtures of formate/glucose and formaldehyde/glucose. In continuous cultures of the catalase-negative mutant grown on these mixtures, MOX can be induced efficiently. To obtain a stable and productive process, the ratio of the substrates is of critical importance. The optimal ratios of the mixtures for the catalase-negative strain for formate/glucose and formaldehyde/glucose were 3:1 and 1–2:1, respectively. Under identical cultivation conditions the wild-type strain showed similar induction patterns for MOX and the dissimilatory enzymes formaldehyde dehydrogenase (FaDH) and formate dehydrogenase (FoDH). The MOX levels in the catalase-negative strain were approx. 50% of those in the wild-type strain.

The CO stretching vibration dominates the ground-state Raman spectrum of 2-naphthaldehyde. The present study of the resonance Raman spectra of 2-naphthaldehyde and of various isotopically labelled 2-naphthaldehydes in the lowest ππ* triplet state, reveals the absence of lines due to vibrational modes involving displacements of atoms in the aldehyde group. All the lines in the triplet-state Raman spectra may be assigned satisfactorily to modes involving only displacements of atoms in the naphthyl group of the triplet-state molecule. This result supports the view that there is no conjugation between the naphthyl and the aldehyde group in the triplet state concerned. The synthesis of the isotopically labelled compounds is described.

A new arrangement for five-pass interferometry is presented together with a holder for wavelength scanning and mirror alignment. The parallelism of the mirror surfaces can be controlled precisely through independent rotations around two mutually perpendicular axes and the distance between the mirrors can be varied by 860 nm independently of the angular controls. Necessary modifications in the design for scanning in other wavelength ranges are outlined.

This investigation focuses on the effect of the death of a family member on the number and type of diagnosed illnesses of the remaining members. The data on mortality and morbidity were obtained from a continuous morbidity register. A total of 225 cases of death were selected, involving 313 family members. A control group of 4909 people who had not been confronted with a death of a family member were selected. A comparison of morbidity rates for the two groups showed that morbidity rates, both for minor and serious illnesses, were affected by the death of a family member. Increases in minor illnesses occurred more often when people had been confronted with death after a chronic illness; increases in serious illnesses were mainly found among people confronted with sudden death. Surprisingly, people with nervous disorders in their medical history showed fewer diagnoses for minor illnesses after a sudden death of a family member. An explanation may be found in the basic principles of family medicine.

The molecular basis of interindividual clinical variability upon infection withStaphylococcus aureusis unclear. We describe patients with haploinsufficiency for the linear deubiquitinase OTULIN, encoded by a gene on chromosome 5p. Patients suffer from episodes of life-threatening necrosis, typically triggered byS. aureusinfection. The disorder is phenocopied in patients with the 5p− (Cri-du-Chat) chromosomal deletion syndrome. OTULIN haploinsufficiency causes an accumulation of linear ubiquitin in dermal fibroblasts, but tumor necrosis factor receptor–mediated nuclear factor κB signaling remains intact. Blood leukocyte subsets are unaffected. The OTULIN-dependent accumulation of caveolin-1 in dermal fibroblasts, but not leukocytes, facilitates the cytotoxic damage inflicted by the staphylococcal virulence factor α-toxin. Naturally elicited antibodies against α-toxin contribute to incomplete clinical penetrance. Human OTULIN haploinsufficiency underlies life-threatening staphylococcal disease by disrupting cell-intrinsic immunity to α-toxin in nonleukocytic cells.