Controlling broad-leaved dock (Rumex obtusifolius) in grass clover mixtures

This article describes three experiments on the control of broad-leaved dock. Experiment 1: Dock seeds were ensiled in grass silages of different dry matter percentages; 23, 34 and 60% respectively. All silages showed a decline of seed vitality in time. Grass clover with dock seeds should be ensiled at a low dry matter percentage or remain in the silage bin for a longer period than 8 weeks. Experiment 2: In a potassium fertilisation trial on grass clover the development of dock was followed. After two years of potassium fertilisation, the number of dock and the root mass was not significant different between the fertilised and the unfertilised plots. It is concluded that potassium fertilisation at a low potassium status does not positively influence the dock development. Experiment 3: In a resown grass clover, dock seedlings were cut at three frequencies; 2, 4 and 6 weeks. After 3 months the number of seedlings had decreased the same in all treatments. However the root biomass of the seedlings was significantly affected. It is concluded that frequent cutting has a negative effect on root biomass but should be practised for a longer period than 12 weeks to have an effect on seedling numbers

Binding of small interfering RNA molecules is crucial for RNA interference suppressor activity of rice hoja blanca virus NS3 in plants

The NS3 protein of rice hoja blanca tenuivirus represents a viral suppressor of RNAi that sequesters small interfering (si)RNAs in vitro. To determine whether this siRNA binding property is the critical determinant for the suppressor activity of NS3, an alanine point mutational analysis was performed and the resulting mutant proteins were tested for both siRNA binding ability and RNAi suppressor activity in plants. Alanine substitutions of lysine residues at position 173-175 resulted in mutant proteins that lost both their affinity for siRNAs and their RNAi suppressor activity in planta. This indicates that siRNA binding of NS3 is indeed essential for the suppressor function of NS3 and that residues at position 173-175 are involved in the siRNA binding and suppressor activit

Environmental factors influencing the spread of the highly pathogenic avian influenza H5N1 virus in wild birds in Europe

A large number of occurrences of the highly pathogenic avian influenza (HPAI) H5N1 virus in wild birds were reported in Europe. The relationship between the occurrence pattern and environmental factors has, however, not yet been explored. This research uses logistic regression to quantify the relationships between anthropogenic or physical environmental factors and HPAI H5N1 occurrences. Our results indicate that HPAI H5N1 occurrences are highly correlated with the following: the increased normalized difference vegetation index (NDVI) in December; intermediate NDVI in March; lower elevations; increased minimum temperatures in January; and reduced precipitation in January. A predictive risk map of HPAI H5N1 occurrences in wild birds in Europe was generated on the basis of five key environmental factors. Independent validation of the risk map showed the predictive model to be of high accuracy (79%). The analysis suggests that HPAI H5N1 occurrences in wild birds are strongly influenced by the availability of food resources and are facilitated by increased temperatures and reduced precipitation. We therefore deduced that HPAI H5N1 occurrences in wild birds in Europe are probably caused by contact with other wild birds and not by contact with domestic poultry. These findings are important considerations for the global surveillance of HPAI H5N1 occurrences in wild birds

[Review of] Stewart Culin. Games of North America Indians

About a dozen years ago, I had the opportunity to buy Stewart Culin\u27s classic work, Garnes of tile North American Indians, published in the 1902-1903 annual report of the Bureau of American Ethnology (BAE), Smithsonian Institution. The original edition numbered 9,682 copies, of which almost half went to the United States Congress. Beautifully illustrated with more than one thousand figures (mainly drawings of recreative artifacts, plus 21 photographic plates), the heavy and gold-embossed volume was offered for $175 by an antique dealer in Maine. Because I knew the fellow, he was willing to shave$50 from the price. Although this was still a fortune for me at the time, I made the purchase, and the book continues to serve me as a reference. Today, this original edition is difficult to get and, no doubt, even more expensive. Because of its ongoing significance as a rich source of detailed information about traditional native entertainment, I welcome its republication by the University of Nebraska Press. The moderate price of this new edition puts Culin\u27s treasure within financial reach of many

On Linear Maps and Seed Sets of Beidleman Near-Vector Spaces

We studied linear mappings in Beidleman near-vector spaces and explored their matrix representations using $R$-bases of $R$-subgroups. Additionally, we developed algorithms for determining the seed number and seed sets of $R$-subgroups within finite-dimensional Beidleman near-vector spaces.Comment: arXiv admin note: text overlap with arXiv:1810.0722

A meta-analysis of transdiagnostic cognitive behavioural therapy in the treatment of child and young person anxiety disorders

Background: Previous meta-analyses of cognitive-behavioural therapy (CBT) for children and young people with anxiety disorders have not considered the efficacy of transdiagnostic CBT for the remission of childhood anxiety. Aim: To provide a meta-analysis on the efficacy of transdiagnostic CBT for children and young people with anxiety disorders. Methods: The analysis included randomized controlled trials using transdiagnostic CBT for children and young people formally diagnosed with an anxiety disorder. An electronic search was conducted using the following databases: ASSIA, Cochrane Controlled Trials Register, Current Controlled Trials, Medline, PsycArticles, PsychInfo, and Web of Knowledge. The search terms included “anxiety disorder(s)”, “anxi∗”, “cognitive behavio∗, “CBT”, “child∗”, “children”, “paediatric”, “adolescent(s)”, “adolescence”, “youth” and “young pe∗”. The studies identified from this search were screened against the inclusion and exclusion criteria, and 20 studies were identified as appropriate for inclusion in the current meta-analysis. Pre- and posttreatment (or control period) data were used for analysis. Results: Findings indicated significantly greater odds of anxiety remission from pre- to posttreatment for those engaged in the transdiagnostic CBT intervention compared with those in the control group, with children in the treatment condition 9.15 times more likely to recover from their anxiety diagnosis than children in the control group. Risk of bias was not correlated with study effect sizes. Conclusions: Transdiagnostic CBT seems effective in reducing symptoms of anxiety in children and young people. Further research is required to investigate the efficacy of CBT for children under the age of 6

Life in the Polar Winter - Strategies of Survival

The perception of the polar winter as a period in which organisms have to struggle for survival is common among people living almost exclusively outside the polar regions, even if sometimes in areas with winter resembling the polar winter. ... For arctic organisms, endemic to and wintering in the far North, the polar winter possibly has a different significance. For these organisms it is often a period of rest, during which they conserve energy and prepare for reproduction in the coming feeding season. Until the last decades of this century, we knew little about the significance of the polar winter for organisms that live there year-round. For migratory species it is obviously a rather intolerable season, but how resident species survive and live through the winter was unknown. ... The series of eight papers presented here ... stem from a multidisciplinary symposium organized by the Arctic Centre of the University of Groningen on the occasion of the 375th anniversary of this university of 1989. ... The guiding question of this symposium was: How do humans and their living resources survive the polar winter? As the resources are both terrestrial and marine, both are discussed when presenting organisms from different trophic levels. ... This series of papers concludes with a study of the successes and misfortunes of western Europeans wintering in the High Arctic in the 16th and 17th centuries and an article about Russian trappers during the 18th and 19th centuries wintering in Spitsburgen. ..