Investigating the selectivity of weed harrowing with new methods

In six field experiments it was investigated whether row spacing, timing, direction and orientation of post-emergence weed harrowing in spring barley influenced the selectivity and whether it is important that increasing intensities of harrowing are generated either by increasing number of passes or increasing driving speed. Selectivity was defined as the relationship between crop burial in soil immediately after treatment and weed control. To estimate crop burial, digital image analysis was used in order to make the estimations objective. The study showed that narrow row spacing decreased selectivity in a late growth stage (21) whereas row spacing in the range of 5.3 cm to 24 cm had no effects in an early growth stage (12). Harrowing across rows decreased selectivity in one out of two experiments. Whether repeated passes with the harrowing were carried out in the same orientation along the rows or in alternative orientations forth and back was unimportant. There were indications that high driving speed decreases selectivity and that repeated passes with low driving speed are better than single treatments with high driving speed. Impacts on selectivity, however, were small and only significant at high degrees of weed control. Timing had no significant impact on selectivity

Langsigtet balance i ukrudtsbestanden

Dokumentet beskriver hvorledes den langsigtede balance i ukrudtsbestanden kan simuleres ved hjælp af en populationsdynamisk model, samt hvordan balancen kan rykkes til landmandens fordel. f.eks ved hjælp af konkurrencestærke sorte

Hearts + Minds Knowledge Round up: Co-Creating Civic Connections for Indigenous and Black Young People in Peel

This knowledge round-up addresses the question: What ought to be prioritized by non-profit organizations for meaningful civic connections for Indigenous and Black young people? The answer to this question is our Hearts + Minds theory of change mapped out in this paper

Nye danske resultater med bekæmpelse af Kveke (Elytrigia repens), Hestehov (Tussilago farfara) og Åkertistel (Cirsium arvense) i økologisk jordbrug

Resultater med rodukrudtsbekæmpelse i økologisk jordbrug i Danmar

Recent advances in weed management in cereals in Denmark

Cultural methods for prevention and improved crop competitiveness against weeds and mechanical weed control

Ethics and Wolf Management: Attitudes Toward and Tolerance of Wolves in Washington State

Approximately seventy-five years after extirpation from Washington State, gray wolves (Canis lupus) returned. As of December 2012, eight packs had arrived from adjacent states and provinces. Delisted from the Federal Endangered Species List in the eastern one-third of Washington, state wildlife managers now have the authority to manage wolves without federal supervision. As a result, one seven-wolf pack has been destroyed. The current study was developed to provide information for managers and policymakers to modify wolf management policies to fit the new regulatory context. Effects of a range of cultural and demographic factors on attitudes toward wolves and tolerance of wolf-human interactions were assessed using surveys mailed to 1,500 residents in Washington State. Factors included risk perception, experience with and knowledge of wolves, socio-demographic factors, and cultural attributes. Unexpectedly, 48.3% of respondents approved of wolves; only 18.1% disapproved of them in the area. Most respondents (57.2%) also indicated that danger to humans was not a reason to disapprove. Disapproval of wolves by suburban respondents (53.7%) was surprisingly greater than by citizens living in rural regions (39.0%). Wildlife managers must avoid preconceived stereotypes and guide differing groups to unite to minimize wolf-human conflicts, building bridges among stakeholders believed to hold irreconcilable differences, in order to support sustainable recovery of wolves

Numerical renormalization group of vortex aggregation in 2D decaying turbulence: the role of three-body interactions

In this paper, we introduce a numerical renormalization group procedure which permits long-time simulations of vortex dynamics and coalescence in a 2D turbulent decaying fluid. The number of vortices decreases as $N\sim t^{-\xi}$, with $\xi\approx 1$ instead of the value $\xi=4/3$ predicted by a na\"{\i}ve kinetic theory. For short time, we find an effective exponent $\xi\approx 0.7$ consistent with previous simulations and experiments. We show that the mean square displacement of surviving vortices grows as $\sim t^{1+\xi/2}$. Introducing effective dynamics for two-body and three-body collisions, we justify that only the latter become relevant at small vortex area coverage. A kinetic theory consistent with this mechanism leads to $\xi=1$. We find that the theoretical relations between kinetic parameters are all in good agreement with experiments.Comment: 23 RevTex pages including 7 EPS figures. Submitted to Phys. Rev. E (Some typos corrected; see also cond-mat/9911032

A novel rare CUBN variant and three additional genes identified in Europeans with and without diabetes : results from an exome-wide association study of albuminuria

Aims/hypothesisIdentifying rare coding variants associated with albuminuria may open new avenues for preventing chronic kidney disease and end-stage renal disease, which are highly prevalent in individuals with diabetes. Efforts to identify genetic susceptibility variants for albuminuria have so far been limited, with the majority of studies focusing on common variants.MethodsWe performed an exome-wide association study to identify coding variants in a two-stage (discovery and replication) approach. Data from 33,985 individuals of European ancestry (15,872 with and 18,113 without diabetes) and 2605 Greenlanders were included.ResultsWe identified a rare (minor allele frequency [MAF]: 0.8%) missense (A1690V) variant in CUBN (rs141640975, =0.27, p=1.3x10(-11)) associated with albuminuria as a continuous measure in the combined European meta-analysis. The presence of each rare allele of the variant was associated with a 6.4% increase in albuminuria. The rare CUBN variant had an effect that was three times stronger in individuals with type 2 diabetes compared with those without (p(interaction)=7.0x10(-4), with diabetes=0.69, without diabetes=0.20) in the discovery meta-analysis. Gene-aggregate tests based on rare and common variants identified three additional genes associated with albuminuria (HES1, CDC73 and GRM5) after multiple testing correction (p(Bonferroni)Peer reviewe

Glycaemic control, disease duration and beta-cell function in patients with Type 2 diabetes in a Swedish community. Skaraborg Hypertension and Diabetes Project.

AimsTo examine determinants for glycaemic control in primary care patients with Type 2 diabetes. MethodsIn a community-based surveillance of primary care patients with Type 2 diabetes, 190 men and 186 women were consecutively identified and examined for cardiovascular risk factors. Insulin resistance and beta-cell function were estimated using homeostasis model assessment (HOMA). Good glycaemic control was defined as HbA1c = 6.5% was associated with duration of diabetes (10.6 vs. 6.4 years, P = 6.5% by 5 years diabetes duration = 1.7; 95% confidence interval (CI) 1.4-2.1) but was lost following additional adjustment for beta-cell function (OR for HbA1c>= 6.5% = 1.3; 95% CI 0.96-1.7). In a separate linear regression with beta-cell function as the dependent variable there was a significant association with HbA1c after adjustments for differences in age, gender, WHR, serum triglyceride levels and diabetes duration (P < 0.001). ConclusionsIncreasing HbA1c by time was associated with declining beta-cell function