797 research outputs found
Messenger RNA translation in Saccharomyces cerevisiae
The aims of this study were to investigate the effects of mRNA abundance, codon bias, and secondary structure formation upon the translation of the PYK mRNA in yeast. A method has been devised to analyse translation in vivo in the yeast S. cerevisiae. The method involves fractionation of yeast polysomes on sucrose density gradients, followed by analysis of the distribution of specific mRNAs across these polysome gradients. Experiments showed that the PYK gene of S. cerevisiae appears to be subject to dosage compensation at the translational level; the PYK mRNA carries significantly fewer ribosomes when it is present at elevated levels within the yeast cell. Experiments were also devised to analyse the effects of codon bias on the translation of the PYK mRNA. The insertion of 13 non-preferred codons into the N-terminus of the coding region of the PYK gene appeared to have no effect on the translation of this mRNA. However, the ribosome loading of a beta-galactosidase coding sequence (codon bias index = -0.05%) was shown to decrease on increasing the abundance of a beta-galactosidase/PYK fusion mRNA. This appears to be due to the detrimental effects of poor codon bias, since the translation of an mRNA with poor codon bias (TRP2) was also affected. Therefore, poor codon bias seems to have a significant influence upon the translation of an mRNA only under "extreme circumstances" (for example, when abnormally high levels of an mRNA with extremely poor codon bias are present). Increasing the secondary structure formation at the 5'-end of the PYK mRNA was also shown to decrease its ribosome loading in vivo. This is thought to be due to inhibition of translational initiation on this mRNA
A comparison of broad-spectrum and narrow-spectrum dry cow therapy used alone and in combination with a teat sealant
The dry period is a critical time in the lactation cycle, offering the optimum time for cure of existing intramammary infection (IMI), while also encompassing the periods of highest susceptibility to new intramammary infection. Until recent years, intramammary infection in the dry period has been controlled with the use of antibiotic dry cow therapy. The aim of this study was to investigate 3 different dry cow therapy regimens, in low-somatic cell count (SCC; bulk milk SCC < 250,000 cells/mL) herds in southwest England. A total of 489 cows was recruited to the study and randomly allocated to receive either the broad-spectrum antibiotic cefquinome, a combination treatment comprising the narrow-spectrum antibiotic cloxacillin and an internal teat sealant, or the narrow-spectrum antibiotic cloxacillin alone. All quarters were sampled for bacteriology at drying off and again in the week immediately postcalving; 2 quarters were also sampled 2 wk before the estimated calving date to allow an assessment of infection dynamics during the dry period. Quarters were subsequently monitored for clinical mastitis for the first 100 d of lactation. Conventional multilevel (random effects) models were constructed to assess the efficacy of products in preventing IMI. Survival analysis was used to examine factors that influenced the risk of clinical mastitis using conventional Cox proportional hazards models. No differences were identified between the treatment groups in terms of cure of IMI caused by the major pathogens. Quarters in both the combination and cefquinome-treated groups were more likely to be free of a major pathogen or enterobacterial pathogen postcalving. With respect to clinical mastitis, the cefquinome-treated group was less likely to develop clinical mastitis than was the cloxacillin treated group
Measurement of CP Violation at the without Time Ordering or
I derive the expressions for the CP-violating asymmetry arising from
interference between mixed and direct decays in the Upsilon(4S) system, for the
case in which only one of the B decay times is observed, integrating over the
decay time of the other B. I observe that neither the difference of the decay
times Delta t, nor even their time-ordering, need be detected. A technique for
measurement of the CP-violating weak decay parameter sin(2beta) is described
which exploits this observation.Comment: 9 pages postscript, also available through
http://w4.lns.cornell.edu/public/CLN
Strain transfer and partitioning between the Panamint Valley, Searles Valley, and Ash Hill fault zones, California
We report new geologic and geomorphic observations that bear on the interpretation of connectivity and strain transfer among the Panamint Valley, Searles Valley, and Ash Hill fault zones, southern Walker Lane belt of California. Although these faults partition strain regionally onto dominantly normal and strike-slip structures, strain transfer occurs in a complex way not typical of linked strike-slip and extensional faults. The Searles Valley fault (W-directed normal fault) transfers slip onto the Panamint Valley zone, which changes from dominantly NNW-trending dextral strike-slip to more normal motion where they join. The Ash Hill fault (mostly right-lateral strike slip) transfers strain into the northern continuation of the Searles Valley zone, via a complex array of hanging-wall normal and strike-slip faults. These complex interactions, based on the age of structurally offset markers, appear to be stable over~105 years
UK and Twenty Comparable Countries GDP-Expenditureon-Health 1980-2013: The Historic and Continued Low Priority of UK Health-Related Expenditure
It is well-established that for a considerable period the United Kingdom has spent proportionally less of its
gross domestic product (GDP) on health-related services than almost any other comparable country. Average
European spending on health (as a % of GDP) in the period 1980 to 2013 has been 19% higher than the United
Kingdom, indicating that comparable countries give far greater fiscal priority to its health services, irrespective
of its actual fiscal value or configuration. While the UK National Health Service (NHS) is a comparatively lean
healthcare system, it is often regarded to be at a âcrisisâ point on account of low levels of funding. Indeed, many
state that currently the NHS has a sizeable funding gap, in part due to its recently reduced GDP devoted to
health but mainly the challenges around increases in longevity, expectation and new medical costs. The right
level of health funding is a political value judgement. As the data in this paper outline, if the UK âaffordedâ the
same proportional level of funding as the mean average European country, total expenditure would currently
increase by one-fifth
General and age-specific fertility rates in non-affective psychosis : population-based analysis of Scottish women
The study was funded by Chief Scientist Office, Scottish Government Health and Social Care Directorate (Grant CZH/4/951), NHS Research Scotland (NHS Research Scotland Career Research Fellowship).Peer reviewedPublisher PD
Construction management and lean thinking in highways maintenance
To realize the benefits of BIM in construction management using (4D and 5D applications), it has to be implemented first. There are various BIM implementation plans to select from; with BIM features and guides, companies better understand BIM concepts and can easily choose a plan to apply in their operations. A literature review was conducted and 15 different definitions of BIM were encountered. Twelve different BIM implementation plans were found in publications by academics, software vendors and Architecture/Engineering/Construction (AEC) industry professionals. Those implementation plans were compared using a matrix which covers the complete building lifecycle. This research concludes that out of the 12 implementations plans, three were equipped with additional guides attached to their plans, simplifying project data collection; namely those by Autodesk, Penn State University and Indiana University. One implementation plan that scored very highly (based on 16 key issues identified from the three categories of stakeholders specified in this project) was the implementation plan proposed by a major software vendor. BIM is poised to solve many of the shortcomings reported in the construction industry. However, before realizing the full potential of BIM in construction management, it needs to be systematically implemented
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