21 research outputs found
Military Combat Work: the Reconstitution of the ANC's Armed Underground, 1971–1976
This article describes the African National Congress (ANC) underground in South Africa in the years immediately
preceding the 1976 Soweto uprising, and it makes three main contributions to the existing literature on the topic.
The first is primarily descriptive, and involves providing greater detail than has hitherto been offered on the
ANC’s clandestine organisational presence in neighbouring Swaziland, Mozambique and Tanzania that facilitated
the revival of the underground in South Africa. The other two are of value in analysing the longer history of the
ANC’s armed struggle: firstly, the article describes Military Combat Work, the training regime offered to
Umkhonto we Sizwe cadres in the Soviet Union, and which formed the template that was to guide the prosecution
of the armed struggle in future years. The second involves backdating to the pre-Soweto uprising period, many of
the challenges facing the armed struggle that historians have hitherto characterized as being a post-June 1976
phenomenon. This article describes the Challenges the ANC in exile faced hosting the hundreds of cadres that
joined its ranks after recruiting work within South Africa began in the early to mid-1970s.http://www.tandfonline.com/loi/cast2
Isomerization of Vaccenic Acid to cis and trans C18:1 Isomers During Biohydrogenation by Rumen Microbes
International audienceIn ruminants, cis and trans C18:1 isomers are intermediates of fatty acid transformations in the rumen and their relative amounts shape the nutritional quality of ruminant products. However, their exact synthetic pathways are unclear and their proportions change with the forage:concentrate ratio in ruminant diets. This study traced the metabolism of vaccenic acid, the main trans C18:1 isomer found in the rumen, through the incubation of labeled vaccenic acid with mixed ruminal microbes adapted to different diets. [1-13C]trans-11 C18:1 was added to in vitro cultures with ruminal fluids of sheep fed either a forage or a concentrate diet. 13C enrichment in fatty acids was analyzed by gas-chromatography-mass spectrometry after 0, 5 and 24 h of incubation. 13C enrichment was found in stearic acid and in all cis and trans C18:1 isomers. Amounts of 13C found in fatty acids showed that 95% of vaccenic acid was saturated to stearic acid after 5 h of incubation with the concentrate diet, against 78% with the forage diet. We conclude that most vaccenic acid is saturated to stearic acid, but some is isomerized to all cis and trans C18:1 isomers, with probably more isomerization in sheep fed a forage diet
Impact of subacute ruminal acidosis (SARA) adaptation and recovery on the density and diversity of bacteria in the rumen of dairy cows
Subacute ruminal acidosis (SARA) is characterized by ruminal pH depression and microbial perturbation. The impact of SARA adaptation and recovery on rumen bacterial density and diversity was investigated following high-grain feeding. Four ruminally cannulated dairy cows were fed a hay diet, transitioned to a 65% grain diet for 3 weeks, and returned to the hay diet for 3 weeks. Rumen fluid, rumen solids, and feces were sampled during weeks 0 (hay), 1 and 3 (high grain), and 4 and 6 (hay). SARA was diagnosed during week 1, with a pH below 5.6 for 4.6±1.4 h. Bacterial density was significantly lower in the rumen solids with high grain (P=0.047). Rumen fluid clone libraries from weeks 0, 3, and 6 were assessed at the 98% level and 154 operational taxonomic units were resolved. Week 3 diversity significantly differed from week 0, and community structure differed from weeks 0 and 6 (