Amoebae of strain CL of Physarum polycephalum undergo apogamic development to form multinucleate plasmodia. During the amoebal-plasmodial transition, large uninucleate cells become irreversibly committed to plasmodium development. The transformation of an amoeba to a plasmodium involves a change in the tubulin isotypes expressed and a radical restructuring of cellular microtubules. During the transition the amoebal cytoplasmic microtubules, centrioles and cytoplasmic MTOC must disappear and the plasmodial-specific tubulin isotypes and intranuclear microtubule organising centre (MTOC) must be acquired. In developing cultures, amoebae lose the ability to flagellate before they become committed. Enriched suspensions of committed cells can be obtained by inducing asynchronous differentiating cultures to flagellate and passing the cells through a glass bead column. The resulting committed cells can be cultured, with some synchrony, to form plasmodia on bacterial lawns or in axenic liquid medium but cannot be cultured on axenic agar medium. During mating, cells lose the ability to flagellate early in plasmodium development. Committed cells from mating mixtures can be enriched in a similar way to committed cells of CL and have similar growth characteristics. Uninucleate committed cells of CL have the same DNA content as amoebae and plasmodia but have 6-10 times the amount of RNA. Apogamic committed cells express tubulin isotypes characteristic of amoebae, but after culture in axenic liquid medium, the cells express plasmodial-specific tubulin isotypes. Results suggest that plasmodial-specific tubulin isotypes are switched on in quadrinucleate cells. The amoebal cytoskeleton persists in binucleate and quadrinucleate cells but has disappeared in larger multinucleate cells. Mitosis in uninucleate committed cells is intranuclear (plasmodial-type). The amoebal MTOCs are eliminated during the first few mitotic cycles after commitment and do not become the plasmodial intranuclear MTOCs. Centriole loss apparently occurs before MTOC loss.

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A study has been made of the effects of various treatments on the phagocytosis of 14C-labelled E.coli by amoebae of Dictyostelium discoideum. An assay was also developed for the adhesion of amoebae to glass and the effects of a number of inhibitors on this process have been investigated. The phagocytosis of bacteria was inhibited by chelating agents at millimolar concentrations. The effect of chelators was not apparent in the presence of added divalent cations. However, only a small reduction in cell-glass adhesion was seen with EDTA concentrations that caused large reductions in phagocytosis. The calcium ionophore, A23187 abolished phagocytosis at 40 ug/ml. Pretreatment of amoebae with lanthanum ions completely inhibited both phagocytosis and cell-glass adhesion at low concentrations. Both phagocytosis and adhesion to glass are also strongly inhibited by calmodulin antagonists. Neither cytochalasin B or colchicine affected phagocytosis. Concanavalin A strongly inhibited phagocytosis presumably due to a direct interaction with cell surface glycoproteins, since the effect did not occur in the presence of alpha-methyl mannoside. Both phagocytosis and adhesion to glass were greatly reduced on treatment of the amoebae with tunicamycin, again suggesting glycoprotein involvement. Pretreatment of amoebae for 30 min with 1 mg/ml trypsin or pronase had no effect on phagocytosis, although pretreatment with papain at the same concentration caused some reduction. However, phagocytosis became pronase sensitive on exposure to tunicamycin. Beta-glucosidase also caused a small but consistent reduction in phagocytosis and cell-glass adhesion. Phagosomes were isolated from amoebae by two procedures. In the first, cells were allowed to phagocytose 1 um diameter polystyrene beads. The endocytosed beads were then isolated by flotation on a discontinuous sucrose density gradient. In a second procedure, devised during the course of this work, an attempt was made to isolate phagosomes from ingested glutaraldehyde-fixed E.coli. Analysis of these preparations by SDS-polyacrylamide gel electrophoresis showed a number of differences between them. A comparison of these preparations with "bulk" plasma membrane revealed a considerable similarity of the polypeptide profile with that isolated using fixed E. coli.

The effect of monolaurin (0.35 mM) and lauric acid (5.0 mM) alone and in combination has been tested on growth of three cheesebome strains of Listeria monocytogenes and two strains of L. innocna. The Listeria spp. were grown in Tryptose Soya Yeast Glucose Broth (TSGYB) in shake culture at 10 °C and an initial pH of 7.0. The additives were dissolved in butter oil 10 % (w/v). Lauric acid (5.0 mM) increased the doubling time of the five Listeria spp. by 3 - 8 h at 10 °C. Monolaurin by itself was found to slightly increase or decrease the doubling time depending on the microbial strain. Monolaurin had an augmentative effect when combined with lauric acid in the presence of butter oil, where the doubling time increased between 10 to 15 h depending on the strain. Inhibition of Listeria spp. was seen in the model bi-phasic broth system. A model food system was developed to test the antimicrobial properties of lauric acid and monolaurin, where the fat soluble additives were dissolved in cream and milk with 3.6% (w/v) fat. The milk was reconstituted from skim milk and cream 40 % (w/v) fat containing lauric acid or monolaurin. This milk was used to make a soft-ripened cheese of the Brie Camembert type. Two strains of L. innocna were added to the reconstituted milk. During production of the soft-ripened cheese, a draining table was designed to comply with COSHH regulations so that the whey containing L. innocua could be removed and disposed of by heating for 30 min at 121 °C.In cheeses without lauric acid or monolaurin the population of L. innocua increased from 10[3] g[-1] to 10[7] cfu g[-1] on the surface of the cheese. The counts in the centre of the cheese were less at 10[5] cfu g[-1] after ripening for 28 d at 10 °C. Addition of 0.9 mM monolaurin reduced the count to 10[5] cfu g[-1] after 28 d ripening at 10 °C on the surface of the cheese. The effect of increasing the initial draining time at ambient temperature from 24 h to 48 h reduced the population to 0 after 28 d ripening at 10 °C. Unlike experiments in broth culture, addition of lauric acid changed the aroma of the Camembert-type cheese to give a blue cheese aroma. This was due to the conversion of lauric acid to a methyl ketone (2-undecanone) by the starter fungus Penicillium camembertii. Due to lack of stability of lauric acid in this system, lauric acid was omitted from the reconstituted milk in further experiments. During production of cheese, lactose was converted to mainly lactic acid by metabolism of the lactic acid starter. The presence of lactic acid combined with the added monolaurin resulted in a significant reduction in the population of L. innocua particularly when the draining time was increased from 24 h to 48 h. The unusual approach in this study was to dissolve the biocide in the non-aqueous phase, butter oil in the experiments in broth culture and in cream in the model cheese experiments. An untrained taste panel detected monolaurin (0.9 mM) in soft-ripened cheese. Some respondents liked the 'mature' taste whilst others described it as 'farmyard like'. In food systems the use of antimicrobials which result in an increase in the lag phase or a reduction in the overall population of pathogens, has a significant role in promoting the microbiological safety of a product which is eaten without further heat treatment.

Trä har byggnadsfysikaliska egenskaper som skiljer   det från en del andra material som traditionellt har blivit använda som   bärande delar vid byggen. Träets hygroskopiska egenskaper och låga egenvikt   ger andra användningsområden än till exempel betong eller stål. Dess låga   egenvikt ger också spännande konstruktionsmässiga möjligheter och kan göra   det möjligt att bygga på platser som annars inte är tillgängliga utan   användning av mer avancerande tekniker och transportmetoder. I denna rapport har en del av ytterväggen till en   stuga undersökts med avsikt att bedöma huruvida det i väggkonstruktionen   kommer uppstå problem med mögelangrepp. Den undersökta delen av väggen ligger   tre meter under marknivå. Väggen är konstruerad med en ångspärr mot marken   och med ett en meter tjockt lager cellglasgrus mot denna. Innanför   cellglasgruset är det en geotextil, 2 x 100 mm träfiberisolering samt 93 mm   vertikalt timrat limträtimmer vilket också utgör ytskiktet på invändig sida. Undersökningen utfördes som en analys av en   simulering som blev genomförd med mjukvaran WUFI® Pro 6.1. Resultaten av   analysen var kvantitativa data i form av grafer och diagram. Resultatet av simuleringen visade att det inte   kommer uppstå problem med mögel i konstruktionen. Dock är träets   fuktbuffrande egenskaper tydliga och det anses generellt viktigt att se till   att material har en inbyggnadsfukthalt som är under det som är gynnsamt för   växt av mögel. / Wood has physical   properties that makes it different from most other materials that   traditionally has been used as load bearing parts when constructing a   building. The hygroscopic properties and low relative weight of wood makes   room for a different field of application than what is the case with for   instance concrete or steel. Its low relative weight also gives interesting   constructional possibilities and can make it possible to build on sites   otherwise inaccessible without advanced techniques and means of transport. In this report   the lower part of an exterior wall in a mountain cabin has been studied. The   purpose of the study has been to examine whether the cabin will have problems   related to mould or fungus. The examined part of the wall lies three meters   below ground level. It is constructed with a steam barrier towards the ground,   and a one meter thick layer of foam glass fragments on the inside of this.   Further towards the inside of the wall there is a geotextile, two layers of   100 mm wood fibre insulation and one layer of 93 mm thick laminated   vertically timbered timber, which faces the inside of the cabin. The examination   was performed as an analysis of a simulation made with the software WUFI® Pro   6.1. The results of the analysis were quantitative data in the form of graphs   and diagrams that were easily assessed against relevant literature. The results from   the simulation showed that the construction would not have any problems   related mould or fungus. However, the moisture buffering properties of the   wood are obvious, and it is generally considered important that materials have   a built-in moisture that is below what is favourable for mould or fungus   growth. / <p>Betyg 2019-06-05</p>

International Telemetering Conference Proceedings / October 17-20, 1988 / Riviera Hotel, Las Vegas, Nevada / In this paper, a programming parallel real-time process data flow telemetry system is presented. What we developed recently is a advanced telemetry system which can process multi-data-flow of multi-target for mulit-user at the same time. It can be used in RPV, missile and others. Its main characteristics are as follows: Input radio frequency is S wave band (multi-dot frequencies). In telemetry front-end, the chip microprocessor is used to make demodulation and decode. Telemetry preprocessor consists of parallel distributed chip microprocessor mould plates (bus link). There are menu shope man-computer dialogue, figure display, intelligence display and intelligence self-diagnosis in this system. Now, we have developed data compress mould plate, floating-point arithmetic mould plate, derive calculation mould plate and signal process mould plate etc. The main computer is VAX-II.