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A subject of continuing debate is how the Earth's lithospheric portion of the upper mantle has remained the thickest (> 200 km) and oldest (> 3 Gy) beneath cratons and is yet surrounded by a vigorously convecting asthenosphere. It is generally admitted that water is a key parameter in the strength and longevity of cratonic roots, because olivine, the main phase of the lithospheric mantle, becomes stronger if its water content decreases. Expanding upon the work presented in Novella et al. (2015) and Taylor et al. (2016), we report new water contents for additional olivine inclusions in diamonds together with the trace-element composition for all olivine inclusions, as well as for mantle xenoliths from various kimberlite pipes located on the Siberian craton. The olivine diamond inclusions from this study have systematically low-water contents (< 50 ppmw H2O), moderate to high forsterite (e.g., Fo91–94) contents and low Ni, Co, and Zn ppm contents (e.g., < 2848, < 108, and < 47 ppm, respectively). In contrast, olivines from Siberian craton mantle xenoliths have a wide range of water contents (6–323 ppmw H2O) and extend to lower-Fo (91–92), Ni, Co, and Zn-rich compositions, compared to the diamond inclusions. Depleted incompatible trace-element concentrations in olivine (0.1–0.001 × Primitive Mantle) advance our hypothesis for the protogenetic origins for the majority of Siberian diamond inclusions. These observations are consistent with the peridotite xenoliths as representing a part of the cratonic lithosphere that has experienced melt re-fertilization, which has also transported water. The olivine diamond inclusions, on the other hand, preserve “micro-samples” of an initial, dry cratonic lithosphere, mostly resulting from melting events. These inclusions are likely sourced from the initial cratonic mantle lithosphere, which thereby, resisted delamination over time, due to its buoyancy and strength, imparted from melt and water depletion, respectively. And thus, our d

Current treatments for inflammatory bowel disease (IBD) are relatively ineffective. Recently, probiotics have emerged as a potential treatment modality for numerous gastrointestinal disorders, including IBD. Few probiotics, however, have undergone appropriate preclinical screening in vivo. The current study compared the effects of four candidate probiotics on development of dextran sulfate sodium (DSS)-induced colitis in rats. Sprague Dawley rats were gavaged 1 mL of the potential probiotic (1 × 1010 CFU/mL), or vehicle, twice daily for 14 days. Strains tested were Lactobacillus rhamnosus GG (LGG), Streptococcus thermophilus TH-4 (TH-4), Bifidobacterium lactis Bb12 (Bb12) and Lactobacillus fermentum BR11 (BR11). Colitis was induced from day 7 to 14 via administration of 2% DSS in drinking water. Disease activity index (DAI) was monitored daily until rats were killed at day 14. DAI decreased in DSS + Bb12 and DSS + BR11 compared to DSS + Vehicle. Colon length increased in DSS + BR11 (10%) and DSS + LGG (10%) compared to DSS + Vehicle. DSS + Bb12 and DSS + BR11 prevented the distal colon crypt hyperplasia evident in DSS + Vehicle, DSS + LGG and DSS + TH-4. BR11 was most effective at reducing colitic symptoms. Bb12 had minimal effects, whilst TH-4 did not prevent DSS-colitis and LGG actually exacerbated some indicators of colitis. Further studies into the potential benefits of L. fermentum BR11 are indicated.

Opposing effects of the prebiotic, fructooligosaccharide, have been reported in experimental colitis. We compared the effects of the prebiotic, fructooligosaccharide, alone and in synbiotic combination with Lactobacillus fermentum BR11, on the development of dextran sulfate sodium-induced colitis in rats. Rats consumed an 18 percent casein-based diet or diet supplemented with 6 percent fructooligosaccharide or maltodextrin for 14 days. The synbiotic group was gavaged 1 ml of L. fermentum BR11 (1 × 109 cfu/ml) twice daily. From Days 7 to 14, colitis was induced via 3 percent dextran sulfate sodium in drinking water. Disease activity was assessed daily, and at killing, gastrointestinal organs were measured, weighed, and examined by quantitative histology, proliferating cell nuclear antigen immunohistochemistry, and colonic myeloperoxidase activity. Administration of dextran sulfate sodium resulted in an increased colitic disease activity, and an increased colon and cecum weight compared with normal controls. Colon and cecum weights were further increased in dextran sulfate sodium+fructooligosaccharide (colon: 19 percent; cecum: 48 percent) and dextran sulfate sodium+fructooligosaccharide/L. fermentum BR11-treated rats (16 and 62 percent) compared with dextran sulfate sodium+vehicle-treatment. Dextran sulfate sodium+fructooligosaccharide-treated rats displayed an 81 percent increase in colonic myeloperoxidase activity compared with dextran sulfate sodium-treated controls. Histologic damage severity scores increased in dextran sulfate sodium+vehicle, dextran sulfate sodium+fructooligosaccharide, and dextran sulfate sodium+fructooligosaccharide/L. fermentum BR11-treated rats compared with normal controls (P < 0.05). Crypt depth increased in all treatments compared with normal controls (P < 0.01). No protection from dextran sulfate sodium-colitis was accorded by fructooligosaccharide alone or in synbiotic combination w

Supplemental fat is routinely included in young pig diets but often removed with increasing weight to match the perceived declining need for high energy as pigs grow and thus to prevent excessive fat deposition during finishing. However, recent results suggest that early positive effects on growth may be lost if fat is removed from subsequent diets and that, for reasons yet to be established, older pigs may be more responsive to supplemental fat than younger pigs (Campbell, 2005). This project was designed to characterize the effects of added fat on performance, carcass quality and the possible mechanisms of why the pig responds like it does to added fat.

Group II and Group I kimberlite diatremes were studied for upper crustal xenoliths in order to estimate the extent of various lithological units of the Karoo Supergroup in the main Karoo basin at times of kimberlite eruption, the Cretaceous erosional history of the area and the approximate vertical extent of the kimberlite diatremes prior to erosion. The results indicated that at the time of Group II kimberlite eruption basaltic lavas of the Drakensberg Group covered the entire area, but by the time of Group I kimberlite eruption they were restricted to the south- eastern half of the area. At the latter time an escarpment is proposed to have existed at the basalt outcrop limit, about 180 km west of its current position. Sandstones of the Stormberg Group had a restricted original distribution in the north and east of the area, while sandstones from all other Karoo groups occurred throughout the entire area. Both Group I and II kimberlite diatremes had vertical extents of about 1 350 m at eruption. Models for kimberlite pipes in the Kimberley cluster should exclude the presence of rocks of the Drakensberg and Stormberg groups, reducing the extent of the diatreme/crater previously proposed from 1 900 to 1 350 m and significantly lowering estimations of the diamond budget provided by the Cretaceous kimberlite pipes to the younger alluvial and marine deposits., Group II and Group I kimberlite diatremes were studied for upper crustal xenoliths in order to estimate the extent of various lithological units of the Karoo Supergroup in the main Karoo basin at times of kimberlite eruption, the Cretaceous erosional history of the area and the approximate vertical extent of the kimberlite diatremes prior to erosion. The results indicated that at the time of Group II kimberlite eruption basaltic lavas of the Drakensberg Group covered the entire area, but by the time of Group I kimberlite eruption they were restricted to the south- eastern half of the area. At the latter time an escarpment is proposed to have existed at the basalt outcrop limit, about 180 km west of its current position. Sandstones of the Stormberg Group had a restricted original distribution in the north and east of the area, while sandstones from all other Karoo groups occurred throughout the entire area. Both Group I and II kimberlite diatremes had vertical extents of about 1 350 m at eruption. Models for kimberlite pipes in the Kimberley cluster should exclude the presence of rocks of the Drakensberg and Stormberg groups, reducing the extent of the diatreme/crater previously proposed from 1 900 to 1 350 m and significantly lowering estimations of the diamond budget provided by the Cretaceous kimberlite pipes to the younger alluvial and marine deposits.