947 resultados para Isolated attosecond pulses
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Idiomarina sp. strain 28-8 is an aerobic, Gram-negative, flagellar bacterium isolated from the bodies of ark shells (Scapharca broughtonii) collected from underwater sediments in Gangjin Bay, South Korea. Here, we present the draft genome sequence of Idiomarina sp. 28-8 (2,971,606 bp, with a G+C content of 46.9%), containing 2,795 putative coding sequences.
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Sugarcane bagasse pretreatment processes using acidified aqueous ethylene glycol (EG) and ionic liquids (ILs) have been reported recently. In this study, recovery of lignins from these processes was conducted, as well as determination of their physico-chemical properties. The amount of lignins recovered from 1-butyl-3-methylimidazolium chloride ([bmim]Cl) with HCl as a catalyst and [bmim][CH3SO3] was ∼42%, and ∼35%–36% by EG with HCl or H2SO4 as a catalyst, respectively. The isolated lignins were characterised using wet chemistry, spectroscopy and thermogravimetry analysis (TGA), and the results compared to soda lignin from NaOH pretreatment of bagasse. The IL and EG lignins contained no or trace amounts of carbohydrates, slightly lower hydrogen content but slightly higher oxygen contents than soda lignin. The IL and EG lignins contained more C-3 and C-5 reactive sites for Mannich reaction and had more p-hydroxypheny propane unit structures than soda lignin. Two-dimensional heteronuclear single quantum coherence (2D HSQC) nuclear magnetic resonance (NMR) identified the major substructural units in the lignins, and allowed differences among them to be studied. As EG lignins were extracted in very reactive environment, intermediate enol ethers were formed and led to cleavage reactions which were not apparent in the other lignins. 31P NMR and infra-red spectroscopy results showed that IL and EG lignins had lower total hydroxyl content than soda lignin, probably indicating that a higher degree of self-polymerisation occurred during bagasse pretreatment, despite the use of lower temperature and shorter reaction time. On the basis of the salient features of these lignins, potential applications were proposed.
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In this paper two nonlinear model based control algorithms have been developed to monitor the magnetorheological (MR) damper voltage. The main advantage of the proposed algorithms is that it is possible to directly monitor the voltage required to control the structural vibration considering the effect of the supplied and commanded voltage dynamics of the damper. The efficiency of the proposed techniques has been shown and compared taking an example of a base isolated three-storey building under a set of seismic excitations. Comparison of the performances with a fuzzy based intelligent control algorithm and a widely used clipped optimal strategy has also been shown.
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Reaction of the title compound (1a) with anhydrous MeOH-HCl gave 2-endo-(2,6-dimethoxyphenyl)-2-exo-methyl-5-methylbicyclo[3.2.1]octane-6,8-dione (3a), 1,5,14-timethoxy-5,8-seco-6,7-dinorestra-1,3,5(10),9(11)-tetraen-17-one (4), 1,5-dimethoxy-5,8-seco-6,7-dinorestra-1,3,5(10),8,14-pentaen-17-one (5), and 3,4,5,6-tetrahydro-2,7-dimethoxy-3,6-dimethyl-3,2,6-(13-oxopropan[1]yI[3]ylidene)-2H-1-benzoxocin (6). Structures assigned to compounds (3a), (4), and (6) are based on spectral data. The exo-tricyclic acetal structure (6) was further confirmed by the analysis of the 1H n.m.r. spectra of the isomeric alcohols (11) and (12), obtained by sodium borohydride reduction of (6).
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AIMS: To examine pigs at slaughter in New Zealand for the presence of Pasteurella multocida, and to determine for isolates, their biochemical profi les, somatic and capsular types, and the presence or absence of the HSB and toxA genes, associated with haemorrhagic septicaemia (HS) and progressive atrophic rhinitis (PAR), respectively. METHODS: Swabs from 173 lungs, 158 palatine tonsils and 82 nasal passages of pigs at two abattoirs in New Zealand were cultured for P. multocida using conventional techniques, and isolated colonies were subjected to biochemical tests for identi- fi cation of biovars. Somatic serotyping was conducted using an agar gel immunodiffusion (AGID) test. Polymerase chain reaction (PCR) assays were used to confi rm phenotypic identifi cation of colonies using species-specifi c primers, capsule type using serogroup-specifi c primers and multiplex PCR, and to test for the presence of HSB and toxA genes. RESULTS: Pasteurella multocida was isolated from 11/173 (6.4%) lung, 32/158 (20.2%) palatine tonsil and 5/82 (6.1 %) nasal swab samples, a total of 48 isolates from 413 samples (11.6%). Isolation rates per farm ranged from 1–53% of tissue samples collected from pigs 5–6 months of age. On phenotypic characterisation, isolates were allocated to seven main biovars, viz 1, 2, 3, 5, 9, 12, and a dulcitol-negative variant of Biovar 8, the majority (30/48) being Biovar 3. Of the 42 isolates for which somatic serotyping was conducted, 10% were Serovar 1, 79% were Serovar 3, 2% were Serovar 6,1, 2% were Serovar 12, and 7% could not be typed. All 48 isolates were confi rmed as P. multocida using a species-specifi c PCR. In the capsular multiplex PCR, 92% of isolates were Capsular (Cap) type A, 2% were Cap D, and 6% could not be typed. None of the samples were positive for the HSB or toxA genes. CONCLUSION: Serovars or capsular types of P. multocida associated with HS or PAR in pigs were not detected. Establishment of species-specifi c, capsular and toxin PCR assays allowed the rapid screening of isolates of P. multocida, while serotyping provided an additional tool for epidemiological and tracing purposes.
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Objectives: The aim of this study was to determine the antimicrobial resistance patterns of 125 Campylobacter jejuni and 27 Campylobacter coli isolates from 39 Queensland broiler farms. Methods: Two methods, a disc diffusion assay and an agar-based MIC assay, were used. The disc diffusion was performed and interpreted as previously described (Huysmans MB, Turnidge JD. Disc susceptibility testing for thermophilic campylobacters. Pathology 1997; 29: 209–16), whereas the MIC assay was performed according to CLSI (formerly NCCLS) methods and interpreted using DANMAP criteria. Results: In both assays, no C. jejuni or C. coli isolates were resistant to ciprofloxacin or chloramphenicol, no C. coli were resistant to nalidixic acid, and no C. jejuni were resistant to erythromycin. In the MIC assay, no C. jejuni isolate was resistant to nalidixic acid, whereas three isolates (2.4%) were resistant in the disc assay. The highest levels of resistance of the C. jejuni isolates were recorded for tetracycline (19.2% by MIC and 18.4% by disc) and ampicillin (19.2% by MIC and 17.6% by disc). The C. coli isolates gave very similar results (tetracycline resistance 14.8% by both MIC and disc; ampicillin resistance 7.4% by MIC and 14.8% by disc). Conclusions: This work has shown that the majority of C. jejuni and C. coli isolates were susceptible to the six antibiotics tested by both disc diffusion and MIC methods. Disc diffusion represents a suitable alternative methodology to agar-based MIC methods for poultry Campylobacter isolates.
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Biomineralization of manganese on titanium condenser material exposed to seawater has been illustrated. Biomineralization occurs when the fouling components, namely, the microbes, are able to oxidize minerals present in water and deposit them as insoluble oxides on biofilm surfaces. Extensive biofilm characterization studies Showed that an alarmingly large number of bacteria in these biofilms are capable of oxidizing manganese and are, thereby, capable of causing biomineralization on the condenser material exposed to seawater. This paper addresses studies on understanding the exact role of the microbes in bringing about oxidation of manganese. The kinetics of manganese oxidation by marine Gram-positive manganese oxidizing bacterium Bacillus spp. that was isolated front the titanium surface was studied in detail. Manganese oxidation in the presence of Bacillus cells, by cell free extract (CFE) and heat-treated cell free extract was also studied. The study confirmed that bacteria mediate manganese oxidation and lead to the formation of biogenic oxides of MnO2 eventually leading to biomineralization on titanium surface exposed to seawater.
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This paper reports on a Leptospira isolate of bovine origin and its identification as belonging to a previously unknown serovar, for which the name Topaz is proposed. The isolate (94-79970/3) was cultured from bovine urine from a north Queensland dairy farm in Australia. Strain 94-79970/3 grew at 30 °C in Ellinghausen McCullough Johnson Harris (EMJH) medium but failed to grow at 13 °C in EMJH medium or in the presence of 8-azaguanine. Serologically, strain 94-79970/3 produced titres against the Leptospira borgpetersenii serovar Tarassovi, the reference strain for the Tarassovi serogroup; however, no significant titres to any other serovars within the serogroup were obtained. Using 16S rRNA and DNA gyrase subunit B gene analysis, strain 94-79970/3 was identified as a member of the species Leptospira weilii. We propose that the serovar be named Topaz, after the location where the original isolate was obtained. The reference strain for this serovar is 94-79970/ 3 (=KIT 94-79970/35LT722).
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Mastreviruses (family Geminiviridae) that infect monocotyledonous plants occur throughout the temperate and tropical regions of Asia, Africa, Europe and Australia. Despite the identification of a very diverse array of mastrevirus species whose members infect African monocots, few such species have been discovered in other parts of the world. For example, the sequence of only a single monocot-infecting mastrevirus, Chloris striate mosaic virus (CSMV), has been reported so far from Australia, even though earlier biological and serological studies suggested that other distinct mastreviruses were present. Here, we have obtained the complete nucleotide sequence of a virus from the grass Digitaria didactyla originating from Australia. Analysis of the sequence shows the virus to be a typical mastrevirus, with four open reading frames, two in each orientation, separated by two non-coding intergenic regions. Although it showed the highest levels of sequence identity to CSMV (68.7%), their sequences are sufficiently diverse for the virus to be considered a member of a new species in the genus Mastrevirus, based on the present species demarcation criteria. We propose that the name first used during the 1980s be used for this species, Digitaria didactyla striate mosaic virus (DDSMV).
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The project aims at improving the productivity and profitability of mung beans, soy beans and peanuts.
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A model has been developed to predict heat transfer rates and sizes of bubbles generated during nucleate pool boiling. This model assumes conduction and a natural convective heat transfer mechanism through the liquid layer under the bubble and transient conduction from the bulk liquid. The temperature of the bulk liquid in the vicinity of the bubble is obtained by assuming a turbulent natural convection process from the hot plate to the liquid bulk. The shape of the bubble is obtained by equilibrium analysis. The bubble departure condition is predicted by a force balance equation. Good agreement has been found between the bubble radii predicted by the present theory and the ones obtained experimentally.
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BACKGROUND: Familial isolated hyperparathyroidism (FIHP) is an autosomal dominantly inherited form of primary hyperparathyroidism. Although comprising only about 1% of cases of primary hyperparathyroidism, identification and functional analysis of a causative gene for FIHP is likely to advance our understanding of parathyroid physiology and pathophysiology. METHODS: A genome-wide screen of DNA from seven pedigrees with FIHP was undertaken in order to identify a region of genetic linkage with the disorder. RESULTS: Multipoint linkage analysis identified a region of suggestive linkage (LOD score 2.68) on chromosome 2. Fine mapping with the addition of three other families revealed significant linkage adjacent to D2S2368 (maximum multipoint LOD score 3.43). Recombination events defined a 1.7 Mb region of linkage between D2S2368 and D2S358 in nine pedigrees. Sequencing of the two most likely candidate genes in this region, however, did not identify a gene for FIHP. CONCLUSIONS: We conclude that a causative gene for FIHP lies within this interval on chromosome 2. This is a major step towards eventual precise identification of a gene for FIHP, likely to be a key component in the genetic regulation of calcium homeostasis.
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Menangle virus (MenPV) is a zoonotic paramyxovirus capable of causing disease in pigs and humans. It was first isolated in 1997 from stillborn piglets at a commercial piggery in New South Wales, Australia, where an outbreak of reproductive disease occurred. Neutralizing antibodies to MenPV were detected in various pteropid bat species in Australia and fruit bats were suspected to be the source of the virus responsible for the outbreak in pigs. However, previous attempts to isolate MenPV from various fruit bat species proved fruitless. Here, we report the isolation of MenPV from urine samples of the black flying fox, Pteropus alecto, using a combination of improved procedures and newly established bat cell lines. The nucleotide sequence of the bat isolate is 94% identical to the pig isolate. This finding provides strong evidence supporting the hypothesis that the MenPV outbreak in pigs originated from viruses in bats roosting near the piggery. © 2012 Printed in Great Britain.
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Fish collected after a mass mortality at an artificial lake in south-east Queensland, Australia, were examined for the presence of nodularin as the lake had earlier been affected by a Nodularia bloom. Methanol extracts of muscle, liver, peritoneal and stomach contents were analysed by HPLC and tandem mass spectrometry; histological examination was conducted on livers from captured mullet. Livers of sea mullet (Mugil cephalus) involved in the fish kill contained high concentrations of nodularin (median 43.6 mg/kg, range 40.8-47.8 mg/kg dry weight; n = 3) and the toxin was also present in muscle tissue (median 44.0 mu g/kg, range 32.3-56.8 mu g/kg dry weight). Livers of fish occupying higher trophic levels accumulated much lower concentrations. Mullet captured from the lake 10 months later were also found to have high hepatic nodularin levels. DNA sequencing of mullet specimens revealed two species inhabiting the study lake: M. cephalus and an unidentified mugilid. The two mullet species appear to differ in their exposure and/or uptake of nodularin, with M. cephalus demonstrating higher tissue concentrations. The feeding ecology of mullet would appear to explain the unusual capacity of these fish to concentrate nodularin in their livers; these findings may have public health implications for mullet fisheries and aquaculture production where toxic cyanobacteria blooms affect source waters. This report incorporates a systematic review of the literature on nodularin measured in edible fish, shellfish and crustaceans.
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We report here the structures and properties of heat-stable, non-protein, and mammalian cell-toxic compounds produced by spore-forming bacilli isolated from indoor air of buildings and from food. Little information is available on the effects and occurrence of heat-stable non-protein toxins produced by bacilli in moisture-damaged buildings. Bacilli emit spores that move in the air and can serve as the carriers of toxins, in a manner similar to that of the spores of toxic fungi found in contaminated indoor air. Bacillus spores in food cause problems because they tolerate the temperatures applied in food manufacture and the spores later initiate growth when food storage conditions are more favorable. Detection of the toxic compounds in Bacillus is based on using the change in mobility of boar spermatozoa as an indicator of toxic exposure. GC, LC, MS, and nuclear magnetic resonance NMR spectroscopy were used for purification, detection, quantitation, and analysis of the properties and structures of the compounds. Toxicity and the mechanisms of toxicity of the compounds were studied using boar spermatozoa, feline lung cells, human neural cells, and mitochondria isolated from rat liver. The ionophoric properties were studied using the BLM (black-lipid membrane) method. One novel toxin, forming ion channels permeant to K+ > Na+ > Ca2+, was found and named amylosin. It is produced by B. amyloliquefaciens isolated from indoor air of moisture-damaged buildings. Amylosin was purified with an RP-HPLC and a monoisotopic mass of 1197 Da was determined with ESI-IT-MS. Furthermore, acid hydrolysis of amylosin followed by analysis of the amino acids with the GS-MS showed that it was a peptide. The presence of a chromophoric polyene group was found using a NMR spectroscopy. The quantification method developed for amylosin based on RP-HPLC-UV, using the macrolactone polyene, amphotericin B (MW 924), as a reference compound. The B. licheniformis strains isolated from a food poisoning case produced a lipopeptide, lichenysin A, that ruptured mammalian cell membranes and was purified with a LC. Lichenysin A was identified by its protonated molecules and sodium- and potassium- cationized molecules with MALDI-TOF-MS. Its protonated forms were observed at m/z 1007, 1021 and 1035. The amino acids of lichenysin A were analyzed with ESI-TQ-MS/MS and, after acid hydrolysis, the stereoisomeric forms of the amino acids with RP-HPLC. The indoor air isolates of the strain of B. amyloliquefaciens produced not only amylosin but also lipopeptides: the cell membrane-damaging surfactin and the fungicidal fengycin. They were identified with ESI-IT-MS observing their protonated molecules, the sodium- and potassium-cationized molecules and analysing the MS/MS spectra. The protonated molecules of surfactin and fengycin showed m/z values of 1009, 1023, and 1037 and 1450, 1463, 1493, and 1506, respectively. Cereulide (MW 1152) was purified with RP-HPLC from a food poisoning strain of B. cereus. Cereulide was identified with ESI-TQ-MS according to the protonated molecule observed at m/z 1154 and the ammonium-, sodium- and potassium-cationized molecules observed at m/z 1171, 1176, and 1192, respectively. The fragment ions of the MS/MS spectrum obtained from the protonated molecule of cereulide at m/z 1154 were also interpreted. We developed a quantification method for cereulide, using RP-HPLC-UV and valinomycin (MW 1110, which structurally resembles cereulide) as the reference compound. Furthermore, we showed empirically, using the BLM method, that the emetic toxin cereulide is a specific and effective potassium ionophore of whose toxicity target is especially the mitochondria.