The qutC gene encoding dehydroshikimate dehydratase has been constitutively overexpressed in Aspergillus nidulans from a range of 1-30-fold over the normal wild-type level. This overexpression leads ...to impaired growth in minimal medium which can be alleviated by the addition of aromatic amino acids to the medium. Overexpression of the qutC gene in mutant strains lacking protocatechuic acid (PCA) oxygenase leads to the build up of PCA in the medium, which can be measured by a simple assay. Measuring the rate of production of PCA in strains overproducing dehydroshikimate dehydratase and correlating this with the level of overproduction and impaired ability to grow in minimal medium lacking aromatic amino acids leads to the conclusion that (a) the metabolites 3-dehydroquinate and dehydroshikimate leak from the AROM protein at a rate comparable with the extent of flux catalysed by the AROM protein, (b) the AROM protein has a low-level channelling function probably as a result of the close juxtaposition of five active sites and (c) this channelling function is only physiologically significant under non-optimal conditions of nutrient supply and oxygenation, when the organism is in situ in its natural environment.
By matching infrared-selected, massive young stellar objects (MYSOs) and compact H ii regions in the Red MSX Source survey to massive clumps found in the submillimetre ATLASGAL (APEX Telescope Large ...Area Survey of the Galaxy) survey, we have identified ∼1000 embedded young massive stars between 280° < ℓ < 350° and 10° < ℓ < 60° with | b | < 1
$_{.}^{\circ}$
5. Combined with an existing sample of radio-selected methanol masers and compact H ii regions, the result is a catalogue of ∼1700 massive stars embedded within ∼1300 clumps located across the inner Galaxy, containing three observationally distinct subsamples, methanol-maser, MYSO and H ii-region associations, covering the most important tracers of massive star formation, thought to represent key stages of evolution. We find that massive star formation is strongly correlated with the regions of highest column density in spherical, centrally condensed clumps. We find no significant differences between the three samples in clump structure or the relative location of the embedded stars, which suggests that the structure of a clump is set before the onset of star formation, and changes little as the embedded object evolves towards the main sequence. There is a strong linear correlation between clump mass and bolometric luminosity, with the most massive stars forming in the most massive clumps. We find that the MYSO and H ii-region subsamples are likely to cover a similar range of evolutionary stages and that the majority are near the end of their main accretion phase. We find few infrared-bright MYSOs associated with the most massive clumps, probably due to very short pre-main-sequence lifetimes in the most luminous sources.
The genes necessary for the correctly regulated catabolism of quinate in Aspergillus nidulans and Neurospora crassa are controlled at the level of transcription by a DNA-binding activator protein and ...a repressor protein that directly interact with one another. The repressor protein is homologous throughout its length with the three C-terminal domains of a pentafunctional enzyme catalysing five consecutive steps in the related anabolic shikimate pathway. We now report that the activator protein is homologous to the two N-terminal domains of the same pentafunctional enzyme and that this proposed structural similarity suggests a molecular mechanism by which the repressor recognises the activator protein. We believe that this is the first report of the genesis of a pair of interacting eukaryotic regulatory proteins by the splitting of a multidomain anabolic enzyme. The recruitment of preformed enzymatically active domains to a regulatory role may represent a general mechanism for the evolution of pathway-specific regulator proteins in dispensible pathways.
The prevalence of erectile dysfunction (ED) increases with age. However, it may emerge at any time during the adult years, and may bear a close relationship to ongoing psychosocial issues affecting ...the patient and his partner. The present study examined ED symptomatology and its associated psychosocial context in 560 men aged 19-87 attending a urology clinic for erectile difficulties. We divided participants into three age groups: early adulthood (age 19-39); middle adulthood (40-59); and late adulthood (60+). They completed a self-report assessment battery evaluating medical, psychological, and lifestyle factors empirically or theoretically related to ED. Results showed that although younger men reported more positive overall ratings of their sex life and better overall erectile functioning relative to older men, they also reported comparatively less relationship satisfaction, greater depressive symptomatology, more negative reactions from partners, and less job satisfaction. Results suggest that older men experience less difficulty than younger men adjusting to life with ED.
This paper summarizes the experience of the Real-Time Outbreak and Disease Surveillance (RODS) project in collecting and analyzing free-text emergency department (ED) chief complaints. The technical ...approach involves real-time transmission of chief-complaint data as Health Level 7 messages from hospitals to a regional data center, where a Bayesian text classifier assigns each chief complaint to one of eight syndrome categories. Time-series algorithms analyze the syndrome data and generate alerts. Authorized public health users review the syndrome data by using Internet interfaces with timelines and maps. Deployments in Pennsylvania, Utah, Atlantic City, and Ohio have demonstrated feasibility of real-time collection of chief complaints. Retrospective experiments that measured case-classification accuracy demonstrated that the Bayesian classifier can discriminate between different syndrome presentations. Retrospective experiments that measured outbreak-detection accuracy determined that the classifier's performance was adequate to support accurate and timely detection of seasonal disease outbreaks. Prospective evaluation revealed that a cluster of carbon monoxide exposures was detected by RODS within 4 hours of the presentation of the first case to an emergency department.
Laser spectroscopy was performed on the {sup 72,74,76,78}Ga isotopes at On-Line Isotope Mass Separator (ISOLDE) facility, CERN. Ground-state nuclear spins and moments were extracted from the measured ...hyperfine spectra. The results are compared to shell-model calculations, which provide a detailed probe of the nuclear wave function. The spin is established from the shape of the hyperfine structure and the parity inferred from a comparison of shell-model calculations with the measured nuclear moments. The ground states of {sup 76,78}Ga are both assigned a spin and parity of I{sup {pi}=}2{sup -}, while {sup 74}Ga is tentatively assigned as I{sup {pi}=}3{sup -}. For {sup 72}Ga, the results are consistent with the previous I=3 assignment.
Using high statistics samples of charged-current numu interactions, the MiniBooNE corrected Collaboration reports a measurement of the single-charged-pion production to quasielastic cross section ...ratio on mineral oil (CH2), both with and without corrections for hadron reinteractions in the target nucleus. The result is provided as a function of neutrino energy in the range 0.4 GeV<Enu<2.4 GeV with 11% precision in the region of highest statistics. The results are consistent with previous measurements and the prediction from historical neutrino calculations.
We report two novel determinations of | V u b | with reduced model dependence, based on measurements of the mass distribution of the hadronic system in semileptonic B decays. Events are selected by ...fully reconstructing the decay of one B meson and identifying a charged lepton from the decay of the other B meson from Υ ( 4 S ) → B ¯¯¯ B events. In one approach, we combine the inclusive ¯¯¯ B → X u ℓ ¯ ν rate, integrated up to a maximum hadronic mass m X < 1.67 GeV / c 2 , with a measurement of the inclusive B → X s γ photon energy spectrum. We obtain | V u b | = ( 4.43 ± 0.38 stat ± 0.25 syst ± 0.29 theo ) × 10 − 3 . In another approach we measure the total ¯¯¯ B → X u ℓ ¯ ν rate over the full phase space and find | V u b | = ( 3.84 ± 0.70 stat ± 0.30 syst ± 0.10 theo ) × 10 − 3 .
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