Propagation velocity and rate of attenuation of surface waves on a homogeneously fluidized bed

Surface waves with a frequency of 0.5¿2.5 Hz were generated on a homogeneously fluidized bed. The propagation velocity and rate of attenuation of the induced pressure fluctuations were measured using signal averaging techniques. The measured wave velocity and attenuation rate correlated well with predictions based on a theory which considers the bed as an incompressible liquid with low viscosity. From the rate of attenuation an effective bed viscosity was calculated between 1.2 and 6.0 Pa · s. At high frequencies the wave generator produced high-amplitude density waves

Public Reactions to People with HIV/AIDS in the Netherlands

A national telephone survey was conducted (1) to assess present-day public reactions to people with HIV/AIDS in the Netherlands, (2) to measure how knowledge about highly active antiretroviral therapy (HAART) is related to public reactions to people with HIV/AIDS, and (3) to investigate determinants of willingness to have personal contact with people with HIV/AIDS. Dutch adults (N = 751) participated in a telephone interview conducted to measure cognitive, emotional and behavioral reactions to people with HIV/AIDS. This study has shown that public reactions to people with HIV/AIDS seem to be moderately positive in the Netherlands. Knowledge about HAART is related to lower risk perceptions, a positive attitude towards homosexuals, less fear and more willingness to have personal contact with people with HIV/AIDS. In particular cognitive, but also emotional factors are meaningfully related to willingness to have personal contact with people with HIV/AIDS. Implications for Dutch AIDS educational campaigns aimed at stigma reduction are discussed

Creation of NOON states by double Fock-state/Bose-Einstein condensates

NOON states (states of the form $|N>_{a}|0>_{b}+|0>_{a}|N>_{b}$ where $a$ and $b$ are single particle states) have been used for predicting violations of hidden-variable theories (Greenberger-Horne-Zeilinger violations) and are valuable in metrology for precision measurements of phase at the Heisenberg limit. We show theoretically how the use of two Fock state/Bose-Einstein condensates as sources in a modified Mach Zender interferometer can lead to the creation of the NOON state in which $a$ and $b$ refer to arms of the interferometer and $N$ is the total number of particles in the two condensates. The modification of the interferometer involves making conditional ``side'' measurements of a few particles near the sources. These measurements put the remaining particles in a superposition of two phase states, which are converted into NOON states by a beam splitter. The result is equivalent to the quantum experiment in which a large molecule passes through two slits. The NOON states are combined in a final beam splitter and show interference. Attempts to detect through which ``slit'' the condensates passed destroys the interference.Comment: 8 pages 5 figure

A Locus for Hereditary Sensory Neuropathy with Cough and Gastroesophageal Reflux on Chromosome 3p22-p24

Hereditary sensory neuropathy type I (HSN I) is a group of dominantly inherited degenerative disorders of peripheral nerve in which sensory features are more prominent than motor involvement. We have described a new form of HSN I that is associated with cough and gastroesophageal reflux. To map the chromosomal location of the gene causing the disorder, a 10-cM genome screen was undertaken in a large Australian family. Two-point analysis showed linkage to chromosome 3p22-p24 (Zmax=3.51 at recombination fraction (θ) 0.0 for marker D3S2338). A second family with a similar phenotype shares a different disease haplotype but segregates at the same locus. Extended haplotype analysis has refined the region to a 3.42-cM interval, flanked by markers D3S2336 and D3S1266

41 Pharmacokinetics of nasally administered tobramycin, colistin sulphomethate sodium and a combination of tobramycin and colistin sulphomethate sodium

The paranasal sinuses can constitute a niche for bacteria which can migrate to the lungs. Nasal administration of antibiotics may be effective, but safety of this treatment has to be established first. Objectives: Investigation of the pharmacokinetics (PK) of nasally administered tobramycin (T), colistin sulphomethate sodium (CSS) and a combination of both drugs using systemic absorption, expressed as % absorbed, as surrogate for safety. In addition, tolerability of the nasal irrigations was examined. Methods: Ten adult CF patients performed three different nasal irrigations: 300 mg of T, 2 million IU of CSS and 300 mg of T combined with 2 million IU of CSS. Serum concentrations T and CSS were analysed using a validated assay. Individual PK parameters were calculated and assimilated with T and colistin serum values using a computerized CF-based population model. Maximum serum level (Cmax), trough serum level (Ctrough ) and bioavailability (F) were calculated. T Cmax >30 mg/L and Ctrough >0.5 mg/L were considered to be toxic. For colistin toxic levels are not known. Tolerability was measured using a Visual Analog Scale (VAS). Results: Following the T and the combined irrigation only 2 patients had detectable tobramycin serum levels with a Cma

Heterologous Processing and Export of the Bacteriocins Pediocin PA-1 and Lactococcin A in Lactococcus Lactis:A Study with Leader Exchange

The bacteriocins pediocin PA-1 and lactococcin A are synthesized as precursors carrying N-terminal extensions with a conserved cleavage site preceded by two glycine residues in positions -2 and -1. Each bacteriocin is translocated through the cytoplasmic membrane by an integral membrane protein of the ABC cassette superfamily which, in the case of pediocin PA-1, has been shown to possess peptidase activity responsible for proteolytic cleavage of the pre-bacteriocin. In each case, another integral membrane protein is essential for bacteriocin production. In this study, a two-step PCR approach was used to permutate the leaders of pediocin PA-1 and lactococcin A. Wild-type and chimeric pre-bacteriocins were assayed for maturation by the processing/export machinery of pediocin PA-1 and lactococcin A. The results show that pediocin PA-1 can be efficiently exported by the lactococcin machinery whether it carries the lactococcin or the pediocin leader. It can also compete with wild-type lactococcin A for the lactococcin machinery. Pediocin PA-1 carrying the lactococcin A leader or lactococcin A carrying that of pediocin PA-1 was poorly secreted when complemented with the pediocin PA-1 machinery, showing that the pediocin machinery is more specific for its bacteriocin substrate. Wild-type pre-pediocin and chimeric pre-pediocin were shown to be processed by the lactococcin machinery at or near the double-glycine cleavage site. These results show the potential of the lactococcin LcnC/LcnD machinery as a maturation system for peptides carrying double-glycine-type amino-terminal leaders

Bloementeelt Lelie: Kleine volumes substraat

Bloementeelt van lelies in bakken met potgrond kost enorme bergen (schaarser wordende) potgrond en staat de voortgang van de mechanisatie op de bedrijven in de weg. Lelietelers willen de handmatige oogst en het tilwerk van de bakken graag kwijt en mechaniseren. Daarom is er de vraag naar alternatieve manieren van bloemen telen. De teelt op water is een alternatief, maar ook de teelt in kleine volumes substraat zou een goede optie kunnen zijn. In de winter van 2002 is het onderzoek naar de bloementeelt van lelies op water afgesloten. Het bleek goed mogelijk om lelies op alleen water te telen. In de proeven op PPO leverde de teelt op water vergelijkbare resultaten op met de teelt in potgrond. Op Proeftuin Zwaagdijk leverde de teelt op water met wortelbesproeiing betere resultaten op in vergelijking met de teelt op potgrond. Omdat de opdrachtgevers echter twijfelen aan de haalbaarheid van deze nieuwe teeltmethode is het onderzoek gestopt. In de laatste proef van dit project werd op verzoek van de begeleidingsgroep ook geëxperimenteerd met substraten in kleine hoeveelheden per bol. Dit oriënterende onderzoek leverde veelbelovende resultaten op. In opdracht van Productschap Tuinbouw en aangestuurd door de studiegroep lelie 01 van LTO Groeiservice hebben PPO Bloembollen en Proeftuin Zwaagdijk gezamenlijk gezocht naar het meest geschikte substraat, de methode van watergeven, het minimale potvolume en naar de meest geschikte afmetingen van de pot (of tray) de lelie het beste groeit. PPO sloot het onderzoek af met een economische evaluatie. Uit het onderzoek van beide onderzoeksinstellingen is gebleken dat de broei van lelies op klein volume substraat goed mogelijk is mits de vochtvoorziening goed is. Naarmate het volume substraat waarop wordt geteeld kleiner is wordt de teelt kwetsbaarder. Een korte periode van uitdroging kan al desastreuse gevolgen hebben voor de takkwaliteit