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Glyphosate-resistant (GR) canola is a widely grown crop across western Canada and has quickly become a prolific volunteer weed. Glyphosate-resistant soybean is rapidly gaining acreage in western Canada. Thus, there is a need to evaluate herbicide options to manage volunteer GR canola in GR soybean crops. The present experiment was conducted to evaluate the efficacy of various PRE- and POST- emergence herbicides applied sequentially to volunteer GR canola, and to evaluate soybean injury caused by these herbicides. Trials were conducted across Saskatchewan and Manitoba in 2014 and 2015. All treatments provided a range of suppression (>70%) to control (>80%) of volunteer canola. All treatments with the exception of the glyphosate treated control reduced aboveground canola biomass by 96% (on average). As well, canola seed contamination was reduced from 36% to less than 5% when a PRE and POST herbicide were both used. Moreover, all combinations of herbicides used had excellent crop safety (<10%). All Pre and Post herbicide combinations provided better control of volunteer canola compared to the glyphosate only control, but tribenuron fb bentazon and tribenuron fb imazamox+bentazon provided solutions that were low cost, currently available (registered in western Canada) and had the potential to minimize development of herbicide resistance in other weeds.
In recent years, soybean acreage has increased significantly in western Canada. One of the challenges associated with growing soybean in western Canada is the control of volunteer glyphosate-resistant (GR) canola, because most soybean cultivars are also glyphosate resistant. The objective of this research was to determine the impact of soybean seeding rate and planting date on competition with volunteer canola. We also attempted to determine how high seeding rate could be raised while still being economically feasible for producers. Soybean was seeded at five different seeding rates (targeted 10, 20, 40, 80, and 160 plants m−2) and three planting dates (targeted mid-May, late May, and early June) at four sites across western Canada in 2014 and 2015. Soybean yield consistently increased with higher seeding rates, whereas volunteer canola biomass decreased. Planting date generally produced variable results across site-years. An economic analysis determined that the optimal rate was 40 to 60 plants m−2, depending on market price, and the optimal planting date range was from May 20 to June 1.
Urban slum environments in the tropics are conducive to the proliferation and the spread of rodent-borne zoonotic pathogens to humans. Calodium hepaticum (Brancroft, 1893) is a zoonotic nematode known to infect a variety of mammalian hosts, including humans. Norway rats (Rattus norvegicus) are considered the most important mammalian host of C. hepaticum and are therefore a potentially useful species to inform estimates of the risk to humans living in urban slum environments. There is a lack of studies systematically evaluating the role of demographic and environmental factors that influence both carriage and intensity of infection of C. hepaticum in rodents from urban slum areas within tropical regions. Carriage and the intensity of infection of C. hepaticum were studied in 402 Norway rats over a 2-year period in an urban slum in Salvador, Brazil. Overall, prevalence in Norway rats was 83% (337/402). Independent risk factors for C. hepaticum carriage in R. norvegicus were age and valley of capture. Of those infected the proportion with gross liver involvement (i.e. >75% of the liver affected, a proxy for a high level intensity of infection), was low (8%, 26/337). Sixty soil samples were collected from ten locations to estimate levels of environmental contamination and provide information on the potential risk to humans of contracting C. hepaticum from the environment. Sixty percent (6/10) of the sites were contaminated with C. hepaticum. High carriage levels of C. hepaticum within Norway rats and sub-standard living conditions within slum areas may increase the risk to humans of exposure to the infective eggs of C. hepaticum. This study supports the need for further studies to assess whether humans are becoming infected within this community and whether C. hepaticum is posing a significant risk to human health.
The purpose of the present study was to investigate the associations of family sociodemographic characteristics with children’s weight status and whether these potential associations are mediated by children’s breakfast habits.
A school-based survey among 10–12-year-old children was conducted in eight European countries. Children’s weight and height were measured and breakfast habits and family sociodemographic characteristics were self-reported by 5444 children and their parents. International Obesity Task Force cut-off points were used to categorize children as overweight/obese or normal weight. Mediation analyses were used to test the potential mediating effect of children’s breakfast consumption on the associations between family sociodemographic characteristics and children’s overweight/obesity.
Schools in eight European countries participating in the ENERGY (EuropeaN Energy balance Research to prevent excessive weight Gain among Youth) project.
Children aged 10–12 years and their parents (n 5444).
Children’s reported daily breakfast consumption varied from 56 % in Slovenia to 92 % in Spain on weekdays and from 79 % in Greece to 93 % in Norway on weekends. Children of native parents, with both parents employed and with at least one parent having more than 14 years of education were more likely to consume breakfast daily and less likely to be overweight/obese. Finally, mediation analyses revealed that the association of parental nationality and parental educational status with children’s overweight/obesity was partially mediated by children’s daily breakfast consumption.
The study shows that the lower likelihood of being overweight/obese among 10–12-year-old children of native background and higher parental educational status was partially mediated by children’s daily breakfast consumption.
To examine the prevalence of human pathogens carried by rats in urban areas in Hanoi and Hai Phong, Vietnam, we live-trapped 100 rats in January 2011 and screened them for a panel of bacteria and viruses. Antibodies against Leptospira interrogans (22·0%), Seoul virus (14·0%) and rat hepatitis E virus (23·0%) were detected in rats, but antibodies against Yersinia pestis were not detected. Antibodies against L. interrogans and Seoul virus were found only in adult rats. In contrast, antibodies to rat hepatitis E virus were also found in juvenile and sub-adult rats, indicating that the transmission mode of rat hepatitis E virus is different from that of L. interrogans and Seoul virus. Moreover, phylogenetic analyses of the S and M segments of Seoul viruses found in Rattus norvegicus showed that Seoul viruses from Hai Phong and Hanoi formed different clades. Human exposure to these pathogens has become a significant public health concern.
This study aimed to compare ‘cool’ [working memory (WM) and response inhibition] and ‘hot’ (delay aversion) executive functions (EFs) in children with and without attention deficit hyperactivity disorder (ADHD).
A total of 100 ADHD children (45 with family history of ADHD and 55 with no family history) and 100 healthy controls, all medication free, were tested on tasks related to the ‘hot’ (i.e. two choice-delay tasks) and ‘cool’ domains of EF (i.e. Digits backward, Corsi Block Task backward, Go/No-Go Task, Stop-Signal Task, and the Stroop).
Compared with the controls, children with ADHD were found to perform significantly worse on one or more measures of response inhibition, WM, and delay aversion after controlling for co-morbidities and estimated IQ. In addition, comparisons between ADHD children with family history of ADHD and those with no family history found significant differences on measures of response inhibition and WM but not delay aversion. These results are largely supported by results of two logistic regressions.
ADHD was found to be associated with deficits on both cool and hot EFs. There is also evidence to suggest that cool EFs impairment is related to a family history of ADHD. Findings of this study have helped to elucidate the nature and extent of EF deficits in children with ADHD.
Affymetrix GeneChip microarrays are a powerful tool to study global gene expression profiles and have been used on many species. However, no sheep-specific Affymetrix GeneChip is currently available and the bovine array is fairly limited in its coverage and annotation. Previously, a probe-selection method based on hybridisation of genomic DNA (gDNA) was developed, which enables GeneChips to be used for species that they were not designed for. This approach can greatly increase the number of potential annotated genes that can be studied beyond that which is currently available, particularly for species that do not have comprehensively characterised genomes. In this study, we demonstrate that gDNA-based probe selection on the Affymetrix Human U133+2 GeneChip array can be used to study gene expression profiles in sheep tissues. More than 20 000 transcripts were detected in triplicate ovine skeletal muscle and liver samples, which is more than would be possible using the commercially available sheep-specific microarray. The majority of the top 15 differentially expressed genes for each tissue were known to either be expressed in a tissue-specific manner or relate to specific functions of that tissue. Gene ontology analysis of the differentially expressed genes revealed the expected differences in gene expression profiles between the two tissues. Besides demonstrating that the probe selection method can be used to study the ovine transcriptome, the benefits of this approach are that it can greatly increase the number of annotated and novel genes that can be studied beyond those currently possible using ovine- or bovine-specific microarrays. This same method also has the potential to allow the study of other species where species-specific microarrays are not available or whose genomes have not been comprehensively characterised.
When solid stands of foxtail millet are cut for swath grazing, the grazing season for cattle is extended and winter feeding costs reduced. The economic success of this practice depends on inexpensive weed control. Eight single- and double-rate herbicide combinations (g ai/ha) were evaluated and compared to a weed-free check: MCPA + bromoxynil (280 + 280 or 560 + 560); MCPA + clopyralid (560 + 100 or 1120 + 200); MCPA + fluroxypyr (562 + 108 or 1124 + 216); and MCPA + clopyralid + fluroxypyr (560 + 100 + 144 or 1120 + 200 + 288). This study was conducted at Indian Head, Saskatchewan (SK) in 2004, 2005, 2006, and 2007 and at Scott, SK, in 2006 and 2007. Crop injury and dry matter yield were measured. Results of the study indicate that crop injury exceeded 20% at only one out of six sites at 7 to 14 d after herbicide treatment. Double-rate MCPA + bromoxynil treatments had higher injury ratings than the weed-free check 7 to 14 d after treatment in all site years. As the growing season progressed, injury ratings tended to decline except at Scott in 2007, where injury ratings at the 21 to 35 d period were numerically greater than the other two rating periods. There were no differences among treatments for crop biomass production. We conclude that all four herbicide combinations at the labeled rate are safe to use on foxtail millet in Saskatchewan, and probably in other areas with similar environmental growing conditions.
A prospective cohort study estimated the incidence of hepatitis C virus (HCV) in drug injectors in South Wales (UK). In total, 286/481 eligible seronegative individuals were followed up after approximately 12 months. Dried blood spot samples were collected and tested for anti-HCV antibody and behavioural data were collected at baseline and follow-up. HCV incidence was 5·9/100 person-years [95% confidence interval (CI) 3·4–9·5]. HCV incidence was predicted by community size [incident rate ratio (IRR) 6·6, 95% CI 2·11–20·51, P=0·001], homelessness (IRR 2·9, 95% CI 1·02–8·28, P=0·047) and sharing injecting equipment (IRR 12·7, 95% CI 1·62–99·6, P=0·015). HCV incidence was reduced in individuals in opiate substitution treatment (IRR 0·34, 95% CI 0·12–0·99, P=0·047). In order to reduce follow-up bias we used multiple imputation of missing data using switching regression; after imputation estimated HCV incidence was 8·5/100 person-years (95% CI 5·4–12·7). HCV incidence varies with community size, equipment sharing and homelessness are associated with increased HCV incidence and opiate substitution treatment may be protective against HCV.
A microarray is an orderly arrangement of spots printed on an impermeable solid support, usually glass, silicon chips or nylon membrane. Each gene is represented by multiple spots and a single microarray chip can detect thousands of expressed genes simultaneously and in some cases the entire genome of an organism. Microarrays therefore allow high-throughput determination of changes in expression of thousands of genes of both known and unknown function in response to experimental treatment and so aids in the identification of novel genes associated with physiological pathways. For most mammalian species there is currently either a lack of a specific microarray or a limited coverage of the genome, both of which limit the use of microarrays in those species. For humans and rodents, however, there is complete coverage of the expressed genome. The aim of this study was therefore to determine whether the human Affymetrix GeneChip could be used to measure gene expression in a ruminant species and whether this is a viable alternative to species specific microarrays.
Clinical immunity to Plasmodium falciparum malaria develops after repeated exposure to the parasite. At least 2 P. falciparum variant antigens encoded by multicopy gene families (var and rif) are targets of this adaptive antibody-mediated immunity. A third multigene family of variant antigens comprises the stevor genes. Here, 4 different stevor sequences were selected for cloning and expression in Escherichia coli and His6–tagged fusion proteins were used for assessing the development of immunity. In a cross-sectional analysis of clinically immune adults living in a malaria endemic area in Ghana, high levels of anti-STEVOR IgG antibody titres were determined in ELISA. A cross-sectional study of 90 nine-month-old Ghanaian infants using 1 recombinant STEVOR showed that the antibody responses correlated positively with the number of parasitaemia episodes. In a longitudinal investigation of 17 immunologically naïve 9-month-old infants, 3 different patterns of anti-STEVOR antibody responses could be distinguished (high, transient and low). Children with high anti-STEVOR-antibody levels exhibited an elevated risk for developing parasitaemia episodes. Overall, a protective effect could not be attributed to antibodies against the STEVOR proteins chosen for the study presented here.
We report the results of experiments that attempt to deposit n-type CVD diamond in a standard hot filament reactor using 1%CH4/H2 gas mixtures, using (i) AsH3 as a gas phase source of arsenic, and (ii) evaporated Sb or Sb(Ph)3 as a source of antimony. SIMS measurements revealed that under these conditions, neither Sb nor As is incorporated into the diamond film, and the Raman spectra, electrical conductivity and crystallite morphology remain unchanged from that of undoped diamond. These experiments confirm the predicted low incorporation efficiency for As and Sb, and we conclude that doping CVD diamond with these elements cannot readily be achieved in this manner.
We present data showing how the electrical conductivity and Raman spectra of boron doped ‘cauliflower’-type nanocrystalline (c-NCD) CVD diamond films vary as a function of B content. The conductivity is roughly linear as a function of B content between an onset threshold of ∼5×1020 cm−3 up to ∼6×1021 cm−3, with the higher concentrations giving near metallic conductivity values. The onset threshold may be due to compensating donors due to the large number of impurities and defects in these films. The position of the Lorentzian contribution to the 500 cm−1 Raman feature was used to estimate the B content and compared to the value measured using SIMS. We found that the Raman method overestimated the concentration of B by a factor of ∼5 for these c-NCD films. The shortfall may be explained if only a small fraction of the B found in the small-grained films is being incorporated into substitutional sites. We conclude that in diamond films with a high concentration of grain boundaries, the majority of the B (80% in some cases) must be present at or in the grain boundaries.