1,500 research outputs found
USING BIOLOGY TO BETTER INFORM MARESTAIL [\u3cem\u3eConyza canadensis\u3c/em\u3e (L.) Cronq.] MANAGEMENT
The importance of sustainable weed management practices continues to grow as farmers are increasingly faced with herbicide resistant weed populations. Marestail (Conyza canadensis), also known as horseweed, is a problematic weed in soybean cropping systems that has developed resistance to multiple herbicide modes of action. A two year study was conducted in Lexington, KY, examining timing patterns of marestail emergence and different integrated weed management strategies for marestail prior to no-till soybean. Treatments contained fall and spring applied herbicides with different levels of residual activities, cover crops and combinations of the two. Additionally, yields and partial budget net returns of each management strategy were compared to a resistance weed management treatment and a common weed management program that many soybean farmers are employing. Excluding the control population in year one, in both site years, marestail emergence was significantly higher during the fall in all populations. Treatments containing a cover crop suppressed marestail emergence equivalently to treatments using herbicides in both years. There were no significant differences in yields when a cover crop was present in either year. Partial budget net returns varied in treatments using cover crops and synthetic herbicides. A treatment using a cover crop had the highest net returns in both years
An enhanced CRISPR repressor for targeted mammalian gene regulation.
The RNA-guided endonuclease Cas9 can be converted into a programmable transcriptional repressor, but inefficiencies in target-gene silencing have limited its utility. Here we describe an improved Cas9 repressor based on the C-terminal fusion of a rationally designed bipartite repressor domain, KRAB-MeCP2, to nuclease-dead Cas9. We demonstrate the system's superiority in silencing coding and noncoding genes, simultaneously repressing a series of target genes, improving the results of single and dual guide RNA library screens, and enabling new architectures of synthetic genetic circuits
The Grizzly, May 6, 2010
Students in Free Enterprise Wins Regional Competition • Ursinus Celebrates Student Artwork with Annual Exhibit • Students Volunteer with UCARE\u27s Community Week • Gala to Benefit Education in Haiti • Ursinus Bike Share Goes National • Seniors Reflect on UC Memories • Senior Spotlight: UC Softball\u27s Lauren Davis-Macedonia; Track and Field\u27s Travis Youngshttps://digitalcommons.ursinus.edu/grizzlynews/1814/thumbnail.jp
Realising the Ambition - Being Me : National Practice Guidance for Early Years in Scotland
Since 2013 there has been a determined focus by the Scottish Government to work towards realising the ambition for Scotland to be the best place for children to grow up in and learn. Changes to the Children and Young People (Scotland) Act 2014, have resulted in our youngest children, particularly those from birth to starting school, being at the heart of significant new developments. In 2014 Scottish Government started to increase the number of hours of funded provision to 600 hours for 3 and 4 year olds and some two year olds. The national practice guidance, “Building the Ambition” was commissioned at this time to complement the new policy developments and to support practitioners. The further expansion of funded Early Learning and Childcare (ELC) to 1140 hours per year for all 3 and 4 year olds, and for around a quarter of 2 year olds will be available from August 2020. This expansion to 1140 hours seeks not only to extend funded places, but to also improve the quality of our ELC provision across Scotland. We know that the earliest years of life are crucial for every child. Evidence tells us that, if our early learning and childcare offer is to help children fulfil their potential and contribute to closing the poverty related gap in children’s outcomes, it has to be high quality. To support the expansion it was decided to refresh the original Building the Ambition, incorporating and updating relevant aspects of the Pre-Birth to Three guidance and extending across the child’s learning journey into the early years of primary school. This new guidance, Realising the Ambition: Being Me, reflects the original principles and philosophy of Building the Ambition and complements the current policy direction of ELC and early primary education. It aspires to support practitioners in delivering what babies and young children need most and how we can most effectively deliver this in Scotland to give children the best start in life. The practice guidance aims to support anyone who works with and for babies and young children across all areas of Scotland. It has been designed to: build confidence and capability of those who work with children and families from pre-birth to starting school and beyond; make links between practice, theory and policy guidance to reinforce aspects of high quality provision and the critical role practitioners play; clarify some aspects of current practice and provide a reference which practitioners can easily use; support improvement and quality by encouraging discussion, self reflection and questioning about relevant practice in each setting, and; provide advice on achieving the highest quality of ELC and early primary provision that will enable young children to experience and to play their own part in Scotland being the best place in the world to grow up
Daily changes in phytoplankton lipidomes reveal mechanisms of energy storage in the open ocean
© The Author(s), 2018. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Nature Communications 9 (2018): 5179, doi:10.1038/s41467-018-07346-z.Sunlight is the dominant control on phytoplankton biosynthetic activity, and darkness deprives them of their primary external energy source. Changes in the biochemical composition of phytoplankton communities over diel light cycles and attendant consequences for carbon and energy flux in environments remain poorly elucidated. Here we use lipidomic data from the North Pacific subtropical gyre to show that biosynthesis of energy-rich triacylglycerols (TAGs) by eukaryotic nanophytoplankton during the day and their subsequent consumption at night drives a large and previously uncharacterized daily carbon cycle. Diel oscillations in TAG concentration comprise 23 ± 11% of primary production by eukaryotic nanophytoplankton representing a global flux of about 2.4 Pg C yr−1. Metatranscriptomic analyses of genes required for TAG biosynthesis indicate that haptophytes and dinoflagellates are active members in TAG production. Estimates suggest that these organisms could contain as much as 40% more calories at sunset than at sunrise due to TAG production.This work was supported by a grant from the Simons Foundation, and is a contribution of the Simons Collaboration on Ocean Processes and Ecology (SCOPE award # 329108, B.A.S.V.M.). K.W.B. was further supported by the Postdoctoral Scholarship Program at Woods Hole Oceanographic Institution & U.S. Geological Survey
Initial Conditions in String Cosmology
We take a critical look at a recent conjecture concerning the past attractor
in the pre-big-bang scenario. We argue that the Milne universe is unlikely to
be a general past attractor for such models and support this with a number of
examples.Comment: 10 pages standard Latex format, no figures. Submitted to Phys. Rev.
Comment on “Worldwide evidence of a unimodal relationship between productivity and plant species richness”
Fraser et al. (Reports, 17 July 2015, p. 302) report a unimodal relationship between productivity and species richness at regional and global scales, which they contrast with the results of Adler et al. (Reports, 23 September 2011, p. 1750). However, both data sets, when analyzed correctly, show clearly and consistently that productivity is a poor predictor of local species richness
The Angular Correlation Function of Galaxies from Early SDSS Data
The Sloan Digital Sky Survey is one of the first multicolor photometric and
spectroscopic surveys designed to measure the statistical properties of
galaxies within the local Universe. In this Letter we present some of the
initial results on the angular 2-point correlation function measured from the
early SDSS galaxy data. The form of the correlation function, over the
magnitude interval 18<r*<22, is shown to be consistent with results from
existing wide-field, photographic-based surveys and narrower CCD galaxy
surveys. On scales between 1 arcminute and 1 degree the correlation function is
well described by a power-law with an exponent of ~ -0.7. The amplitude of the
correlation function, within this angular interval, decreases with fainter
magnitudes in good agreement with analyses from existing galaxy surveys. There
is a characteristic break in the correlation function on scales of
approximately 1-2 degrees. On small scales, < 1', the SDSS correlation function
does not appear to be consistent with the power-law form fitted to the 1'<
theta <0.5 deg data. With a data set that is less than 2% of the full SDSS
survey area, we have obtained high precision measurements of the power-law
angular correlation function on angular scales 1' < theta < 1 deg, which are
robust to systematic uncertainties. Because of the limited area and the highly
correlated nature of the error covariance matrix, these initial results do not
yet provide a definitive characterization of departures from the power-law form
at smaller and larger angles. In the near future, however, the area of the SDSS
imaging survey will be sufficient to allow detailed analysis of the small and
large scale regimes, measurements of higher-order correlations, and studies of
angular clustering as a function of redshift and galaxy type
The relationship between insecticide resistance, mosquito age and malaria prevalence in Anopheles gambiae s.l. from Guinea.
Insecticide resistance across sub-Saharan Africa may impact the continued effectiveness of malaria vector control. We investigated the association between carbamate and pyrethroid resistance with Anopheles gambiae s.l. parity, Plasmodium falciparum infection, and molecular insecticide resistance mechanisms in Guinea. Pyrethroid resistance was intense, with field populations surviving ten times the insecticidal concentration required to kill susceptible individuals. The L1014F kdr-N1575Y haplotype and I1527T mutation were significantly associated with mosquito survival following permethrin exposure (Prevalence Ratio; PR = 1.92, CI = 1.09-3.37 and PR = 2.80, CI = 1.03-7.64, respectively). Partial restoration of pyrethroid susceptibility following synergist pre-exposure suggests a role for mixed-function oxidases. Carbamate resistance was lower and significantly associated with the G119S Ace-1 mutation. Oocyst rates were 6.8% and 4.2% among resistant and susceptible mosquitoes, respectively; survivors of bendiocarb exposure were significantly more likely to be infected. Pyrethroid resistant mosquitoes had significantly lower parity rates than their susceptible counterparts (PR = 1.15, CI = 1.10-1.21). Our findings emphasize the need for additional studies directly assessing the influence of insecticide resistance on mosquito fitness
Genetic variants affecting cross-sectional lung function in adults show little or no effect on longitudinal lung function decline
Background: Genome-wide association studies have identified numerous genetic regions that influence cross-sectional lung function. Longitudinal decline in lung function also includes a heritable component but the genetic determinants have yet to be defined.
Objectives: We aimed to determine whether regions associated with cross-sectional lung function were also associated with longitudinal decline and to seek novel variants which influence decline.
Methods: We analysed genome-wide data from 4167 individuals from the Busselton Health Study cohort, who had undergone spirometry (12 695 observations across eight time points). A mixed model was fitted and weighted risk scores were calculated for the joint effect of 26 known regions on baseline and longitudinal changes in FEV1 and FEV1/FVC. Potential additional regions of interest were identified and followed up in two independent cohorts.
Results: The 26 regions previously associated with cross-sectional lung function jointly showed a strong effect on baseline lung function (p=4.44×10−16 for FEV1/FVC) but no effect on longitudinal decline (p=0.160 for FEV1/FVC). This was replicated in an independent cohort. 39 additional regions of interest (48 variants) were identified; these associations were not replicated in two further cohorts.
Conclusions: Previously identified genetic variants jointly have a strong effect on cross-sectional lung function in adults but little or no effect on the rate of decline of lung function. It is possible that they influence COPD risk through lung development. Although no genetic variants have yet been associated with lung function decline at stringent genome-wide significance, longitudinal change in lung function is heritable suggesting that there is scope for future discoveries
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