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Glyphosate-resistant (GR) Italian ryegrass is one of the most troublesome weeds in Mississippi row crop production. Fall-applied residual herbicide applications are recommended for control of GR Italian ryegrass. However, carryover of residual herbicides applied in fields for rice production can have a negative impact on rice performance. Field studies were conducted in Stoneville, MS, to determine the effects of fall-applied residual herbicides on rice growth and yield. Herbicide treatments included suggested use rates (1×) of clomazone at 840 g ai ha–1, pyroxasulfone 170 g ai ha–1, S-metolachlor 1,420 g ai ha–1, and trifluralin 1,680 g ai ha–1, and two times (2×) the suggested use rates in the fall before rice seeding. Pooled across application rate, pyroxasulfone, S-metolachlor, and trifluralin injured rice to an extent 28% to 36% greater than clomazone 14 d after emergence (DAE). Rice seedling density and height 14 DAE and rice maturity were negatively affected by all fall-applied herbicides except clomazone. Applications at 2× rates reduced rough rice yields in plots treated with pyroxasulfone, S-metolachlor, and trifluralin compared with clomazone. Pyroxasulfone applied at the 2× rate reduced rough rice yield 22% compared with the 1× rate. Rough rice yield was 90% or greater of the nontreated control in plots treated with either rate of S-metolachlor, and these were comparable with rough rice yields from plots treated with both rates of trifluralin and the 1× rate of pyroxasulfone. Early-season injury and reductions in seedling density and height 14 DAE, would preclude even 1× applications of pyroxasulfone, S-metolachlor, and trifluralin from being viable options for residual herbicide treatments targeting GR Italian ryegrass in the fall before rice seeding. Of the herbicides evaluated, only clomazone should be utilized as a fall-applied residual herbicide treatment targeting GR Italian ryegrass before seeding rice.
With the ban on the use of mammalian protein in the EU and the implementation of restrictive use of fishmeal in animal diets coupled with the increased legislative pressures to reduce nitrogen output from animal production, there is an increased requirement for an alternative protein source, which is lower in overall crude protein percentage while still meeting the animal’s optimum amino acid requirement. Natupro is an alternative nutritionally enhanced GMO free vegetable protein, which carefully matches all of the above criteria, as it is low in crude protein (36%) with a controlled release of amino acid mechanism (Natupro amino acid analysis Table 2). Glucosamine is the inspiration behind Natupro, the combination of sugars and amine moites gave rise to the concept of a sugar carrier, which is the mechanism Natupro uses for the consistent controlled release of amino acids over time. The objective of this current experiment is to access the effect of inclusion of Natupro in the grower pigs diet on nitrogen retention, utilisation, excretion and digestibility.
Phosphorus (P) is an essential mineral for pigs and deficiency can cause rickets, osteomalacia or osteoporosis and has been associated with poor fertility and production performance. Traditionally P has been supplied in the inorganic form as the organic form found in cereal grain (phytic acid) is unavailable to pigs as they lack endogenous phytase. Dietary phytases have been shown to play a major role in pig diets, releasing P from phytic acid thus decreasing the need for supplementary P and reducing P excretion (Harper et al 1997). Phytase supplementation has also been reported to improve digestibility of nitrogen, calcium, magnesium, zinc and copper (Jongbloed et al 1993). Some researchers (e.g. Jongbloed and Kemme 1990) suggest that diet processing may reduce enzyme activity and therefore liquid enzyme products have been developed which can be applied after processing. The aims of this study were to examine the effectiveness of several phytase products (including dry vs. liquid) in improving overall digestibility and reducing excretion of P and other nutrients.
There is considerable literature on phosphorus requirements of pigs and on the use of phytase to improve phosphorus digestibility and reduce P excretion. However, much of this has been concentrated on weaned pigs (eg Beers and Jongbloed, 1992), the finishing stage (eg Russo et al, 1995) or the diets used were synthetic (eg Ketaren et al, 1993). The available P requirement for pigs between 20-50 kg was estimated at 3 g/kg by ARC (1981) but the NRC (1998) estimate is 2.3 g/kg. This paper reports digestibility and P utilisation data on 40 kg pigs using the grower diets employed in a study on the impact of commercially feasible reductions in dietary P content and of phytase inclusion on growth and bone strength (Weatherup et al, 1999).
We present preliminary analysis of new HST observations of the transiting extrasolar planet HD 209458b. Photometric observations were obtained with the Fine Guidance Sensor (FGS) on the Hubble Space Telescope (HST), providing milli-mag precision and high time resolution (40 Hz). The FGS photometry allows us to derive precise stellar/orbital parameters (ephemeris, inclination, limb darkening) and planetary radius, and also allows a search for the presence of planetary rings and satellites. We discuss preliminary results and two approaches to modelling the observations.
Escherichia coli O157 are zoonotic bacteria for which cattle are an important reservoir. Prevalence estimates for E. coli O157 in British cattle for human consumption are over 10 years old. A new baseline is needed to inform current human health risk. The British E. coli O157 in Cattle Study (BECS) ran between September 2014 and November 2015 on 270 farms across Scotland and England & Wales. This is the first study to be conducted contemporaneously across Great Britain, thus enabling comparison between Scotland and England & Wales. Herd-level prevalence estimates for E. coli O157 did not differ significantly for Scotland (0·236, 95% CI 0·166–0·325) and England & Wales (0·213, 95% CI 0·156–0·283) (P = 0·65). The majority of isolates were verocytotoxin positive. A higher proportion of samples from Scotland were in the super-shedder category, though there was no difference between the surveys in the likelihood of a positive farm having at least one super-shedder sample. E. coli O157 continues to be common in British beef cattle, reaffirming public health policy that contact with cattle and their environments is a potential infection source.
The spatial distribution of interstellar dust is clearly important in understanding not only galactic dynamics but also the processing of the dust and the interstellar medium in general. Probably the best spectral region for investigating interstellar dust is the infrared (IR), where the cool dust is likely to radiate. Indeed, one of the most prominent features of the IRAS sky is the ubiquitous cirrus emission, thought to be due to interstellar dust heated by the interstellar radiation field (ISRF), seen at 60 and 100 μm (Low 1984). However, it is difficult to use the cirrus to probe the dust distribution, both because we have no depth information and also because the cirrus, due to its low temperatures (~20 K), is a probe of high-density dust regions. A far more sensitive search could be made if the dust were hotter, that is, in the presence of a greater ultraviolet (UV) flux. We have made use of this fact to search for dust in the vicinity of hot, bright stars, where even a small amount of dust will dominate the total emission along that line of sight.
We have combined observations of about 30 sunlike stars from Mount Wilson, Lowell, and Fairborn Observatories to extend our joint time series from 12 to 17 years. The full range of variation on the decadal timescale has probably now been observed for most of our program stars. Statistical relationships between chromospheric and brightness variability derived earlier by us are confirmed. Young active stars become fainter as their chromospheric Ca II HK emission increases, while older less active stars such as the Sun become brighter as their HK emission increases. The Sun's photometric variation still appears somewhat small in amplitude compared to the other stars in this sample with similar mean chromospheric activity.
Light curve analysis by MDW of the photometry and RV data accumulated to date on HD 209458 has made use of a simulations database created for an 8-day HST observing project led by RLG to look for transits in 47 Tuc. We report progress in developing a consistent set of parameters obtained with our versions of the Wilson-Devinney program, WD98 and wd98k93, specially modified to treat large grid sizes, corresponding to objects with radii exceeding 0.7RJ and masses greater than 0.1 MJ.
This work is supported in part by grants to EFM by Canadian NSERC and by the Univ. of Calgary Research Grants Committee.
Bipolar disorder is a highly heritable polygenic disorder. Recent
enrichment analyses suggest that there may be true risk variants for
bipolar disorder in the expression quantitative trait loci (eQTL) in the
We sought to assess the impact of eQTL variants on bipolar disorder risk
by combining data from both bipolar disorder genome-wide association
studies (GWAS) and brain eQTL.
To detect single nucleotide polymorphisms (SNPs) that influence
expression levels of genes associated with bipolar disorder, we jointly
analysed data from a bipolar disorder GWAS (7481 cases and 9250 controls)
and a genome-wide brain (cortical) eQTL (193 healthy controls) using a
Bayesian statistical method, with independent follow-up replications. The
identified risk SNP was then further tested for association with
hippocampal volume (n = 5775) and cognitive performance
(n = 342) among healthy individuals.
Integrative analysis revealed a significant association between a brain
eQTL rs6088662 on chromosome 20q11.22 and bipolar disorder (log Bayes
factor = 5.48; bipolar disorder P =
5.85×10–5). Follow-up studies across multiple independent
samples confirmed the association of the risk SNP (rs6088662) with gene
expression and bipolar disorder susceptibility (P =
3.54×10–8). Further exploratory analysis revealed that
rs6088662 is also associated with hippocampal volume and cognitive
performance in healthy individuals.
Our findings suggest that 20q11.22 is likely a risk region for bipolar
disorder; they also highlight the informative value of integrating
functional annotation of genetic variants for gene expression in
advancing our understanding of the biological basis underlying complex
disorders, such as bipolar disorder.
Solar System dust particles reflect sunlight, producing the so-called zodiacal light (Leinert 1975). The spectrum of the zodiacal light in the far ultraviolet has been a matter of controversy in the past, and remains a subject of great interest.
In this pilot study, we evaluate an algorithm that uses predictive clinical and laboratory parameters to differentiate between patients with hospital-acquired infection (HAI) and patients without HAI. Seventy-four percent of the studied population of surgical patients could be reliably (negative predictive value of 98%) excluded from detailed assessment by the infection control practitioner.
This article represents a systematic effort to answer the question, What are archaeology’s most important scientific challenges? Starting with a crowd-sourced query directed broadly to the professional community of archaeologists, the authors augmented, prioritized, and refined the responses during a two-day workshop focused specifically on this question. The resulting 25 “grand challenges” focus on dynamic cultural processes and the operation of coupled human and natural systems. We organize these challenges into five topics: (1) emergence, communities, and complexity; (2) resilience, persistence, transformation, and collapse; (3) movement, mobility, and migration; (4) cognition, behavior, and identity; and (5) human-environment interactions. A discussion and a brief list of references accompany each question. An important goal in identifying these challenges is to inform decisions on infrastructure investments for archaeology. Our premise is that the highest priority investments should enable us to address the most important questions. Addressing many of these challenges will require both sophisticated modeling and large-scale synthetic research that are only now becoming possible. Although new archaeological fieldwork will be essential, the greatest pay off will derive from investments that provide sophisticated research access to the explosion in systematically collected archaeological data that has occurred over the last several decades.
We carried out an extensive photometric and spectroscopic investigation of the SPB binary, HD 25558 (see Fig. 1 for the time and geographic distribution of the observations). The ~2000 spectra obtained at 13 observatories during 5 observing seasons, the ground-based multi-colour light curves and the photometric data from the MOST satellite revealed that this object is a double-lined spectroscopic binary with a very long orbital period of about 9 years. We determined the physical parameters of the components, and have found that both lie within the SPB instability strip. Accordingly, both components show line-profile variations consistent with stellar pulsations. Altogether, 11 independent frequencies and one harmonic frequency were identified in the data. The observational data do not allow the inference of a reliable orbital solution, thus, disentangling cannot be performed on the spectra. Since the lines of the two components are never completely separated, the analysis is very complicated. Nevertheless, pixel-by-pixel variability analysis of the cross-correlated line profiles was successful, and we were able to attribute all the frequencies to the primary or secondary component. Spectroscopic and photometric mode-identification was also performed for several of these frequencies of both binary components. The spectroscopic mode-identification results suggest that the inclination and rotation of the two components are rather different. While the primary is a slow rotator with ~6 d rotation period, seen at ~60° inclination, the secondary rotates fast with ~1.2 d rotation period, and is seen at ~20° inclination. Our spectropolarimetric measurements revealed that the secondary component has a magnetic field with at least a few hundred Gauss strength, while no magnetic field was detected in the primary.
The detailed analysis and results of this study will be published elsewhere.