Preparation and Properties of Si Substituted Akaganéite (β-FeOOH)

Crystals of akaganéite containing up to 4 mole % Si in the structure have been synthesized from ferric solutions. The crystals are a mixture of somatoids and twins. The presence of Si strongly promotes twinning of akaganéite. The acid dissolution behaviour of Si-akaganéite is similar to that of unsubstituted akaganéite. The dissolution data indicated that 20% Si is located on the surfaces of the crystals and the remainder is distributed uniformly in the crystal structure. Possible sites for Si in the structure of akaganéite have been considered.     

Penetrating metallic foreign bodies as a cause of peritonitis in 3 horses

Three cases of penetrating metallic foreign bodies causing peritonitis in horses are reported. These cases were presented with varying clinical complaints and duration of clinical signs. Entry of foreign bodies into the abdominal cavity through the skin and body wall is reported for the first time.     

Sulfur retention at intensively studied sites in the U.S. and Canada

We compiled and summarized current literature on S input/output budgets for intensively studied sites and soil plots in the U.S. and Canada and found S retention to be related to both soil order and extent of the last glaciation (Wisconsinan). Zero net retention is associated with Spodosols and was found only at sites north of the limit of Wisconsinan glaciation. Sites south of the limit of glaciation appear to be retaining from 20 to 90% of incoming S. These findings support the hypothesis that there exist regional variations in S retention in North America. Such variations are important in determining and predicting effects of acidic deposition on surface water chemistry.     

Regional patterns of sulfur retention in watersheds of the Eastern US

Retention of S was estimated in watersheds of the Eastern US by calculating S input-output budgets for 678 lake and reservoir watershed systems in the Northeast (NE), 98 lake and reservoir and 61 stream systems of the Southern Blue Ridge Province (SBRP) and 56 stream systems of Shenandoah National Park (SNP). Budgets were determined based on estimates of deposition and output (as surface water) for each of the sites. A variety of estimates of total S deposition were used. Percent S retention is high for sites in the SBRP and SNP but is distributed around zero for sites in the NE. These findings lend support to the hypothesis that patterns exist in S retention relative to the extent of the Late Wisconsinan glaciation.     

DNA synthesis generates terminal duplications that seal end-to-end chromosome fusions

End-to-end chromosome fusions that occur in the context of telomerase deficiency can trigger genomic duplications. For more than 70 years, these duplications have been attributed solely to breakage-fusion-bridge cycles. To test this hypothesis, we examined end-to-end fusions isolated from Caenorhabditis elegans telomere replication mutants. Genome-level rearrangements revealed fused chromosome ends having interrupted terminal duplications accompanied by template-switching events. These features are very similar to disease-associated duplications of interstitial segments of the human genome. A model termed Fork Stalling and Template Switching has been proposed previously to explain such duplications, where promiscuous replication of large, noncontiguous segments of the genome occurs. Thus, a DNA synthesis-based process may create duplications that seal end-to-end fusions, in the absence of breakage-fusion-bridge cycles.     

The effect of grazing versus cutting on dry matter production of multispecies and perennial ryegrass‐only swards

Dry matter (DM) production of multispecies swards compared to perennial ryegrass (Lolium perenne; PRG) swards under intensive grazing warrants investigation as it is relatively unknown. A 5 × 2 factorial experiment, with five sward types and two defoliation methods, was used to investigate the effect of grazing versus cutting on dry matter (DM) production of multispecies and PRG‐only swards. Five sward types were established namely: a PRG‐only sward, receiving 250 kg N ha^?1 year^?1 (PRG250), and a PRG‐only sward (PRG90), a two‐species sward with PRG and white clover (Trifolium repens; PRGWC), a six‐species sward (6S) and a nine‐species sward (9S), each receiving 90 kg N ha^?1 year^?1. Cutting plots measured 1.95 × 10 m and grazing plots measured 10 × 10 m. All plots were harvested concurrently every 21–30 days from April‐November for two years (2015 and 2016). A strip from the grazing plots was cut for DM yield determination prior to turning in cattle for grazing. There was an interaction between sward type and defoliation method (p < .01), whereby there was no effect of defoliation method on the PRG‐only swards, however, the annual DM production of PRGWC, 6S and 9S swards reduced under grazing compared to cutting (p < .001; on average 1,929 kg DM/ha lower). Multispecies swards had lower DM production under grazing compared to cutting, while the DM yield of PRG‐only swards was unaffected by defoliation method.