Sequence heterogeneity of bovine mitochondrial DNA

The displacement-loop (D-loop) region of bovine mitochondrial DNA (mtDNA) isolated from blood leukocytes was studied. A method was devised for the isolation of mtDNA from blood leukocytes based on detergent lysis of the plasma membrane and removal of cell nuclei by centrifugation. Nucleic acids extracted from the residual cytoplasmic fraction contained mtDNA in quantities sufficient for restriction enzyme analysis and for DNA cloning and sequencing;MtDNA was from a herd of Holstein cattle that was established 1968 from diverse genetic sources. Maternal lineages were traced by pedigree analysis to their earliest origins in the late 1800s. MtDNA was isolated from blood leukocytes and nucleotide sequences were determined for the light strand of the 910 base-pair (bp) D-loop region. Fifty-one sites of sequence variation in 38 maternal lineages were identified. Nucleotide substitutions were found at 48 sites (38 transitions and 10 transversions); one nine-bp deletion, and two variable-length poly G/poly C regions of 6-8 bp and of 11-16 bp were found. Nucleotide substitutions were distributed nonrandomly across the D-loop region with avoidance of the 5[superscript]\u27 end (100 bp), a central GC-rich region (80 bp), and the 3[superscript]\u27 end that contains light and heavy strand transcriptional promoters and the origin of heavy strand replication. Variation within maternal lineages was observed at two sites: One G-to-C transversion at nucleotide (nt) 363 and in the length of a poly G/poly C region that extends from nt 351 to nt 363. A cytoplasmic gene tree constructed from the sequence data revealed a bifurcation in the mtDNA of cattle into two major groups based on a transition at nt 169. Sufficient variation seems to exist in mtDNA of cattle for the assignment of animals to cytoplasmic lineages

L843

Gary R. Ross & H. Leroy Brooks, Africanized honey bees, Kansas State University, August 1991

A Messy, but Instructive, Case Study in Design of Experiments

A company manufacturing fans wished to conduct an experimental design to determine the best combination of three factors affecting the breaking torque of the fans. Analysis of the data ceased to be straightforward when the authors found that the data failed the test for homogeneity of variances. After unsuccessfully attempting to transform the data and thereby meet the assumptions necessary to carry on the analysis, the authors relied upon a graphical analysis and a careful study of the means for each design point. This paper describes a statistically sound but novel strategy used to complete the analysis

Military fortifications, weaponry, warfare and military strategy in ancient Syro-Palestine (Iron Age II A)

he title above comprises elements of the strategic studies concept 'foundations of military force'. Military force has been the final arbiter between the political entities of mankind throughout all ages. The prevalence of this social scourge has left a footprint in every dispensation of man's efforts at civilisation. Regrettably, warfare was and remains one of the core characteristics of human nature. The artefacts of antiquity are catalogued in archaeological periods. In nearly every instance each layer of human settlement is separated by the effects of warfare. Rather than a sub-discipline on the periphery it is demonstrated herein that military archaeology, refined with the post-World War Two scientific discipline of polemology, can and ought to be moved onto the centre stage of archaeology. The application of core polemological concepts to IA IIa accurately describes the unfolding of the United Monarchy's capacity to pursue political goals commensurate with its evolutionary war potential.Religious Studies and ArabicM.A. (Biblical Studies

A Development of Concept Structure

A concept, in the context of each of my works, is both intellectual and visual in character. Once a conceptual order is initiated into the work itself the artist becomes accountable for each successive decision and attitude. A realization of the extent to which the artist can distinguish his own expressive world comes out of a personal structuring in one&rsquo;s methods of recognizing and confronting the issues of each concept. In the working process cues for further development are often taken from the concept rather than the pictorial image. The artist takes a stance in the conscious control and development of the interaction between concept and image. The artist&rsquo;s primary opportunity and responsibility in relation to contemporary developments in art is in making use of them as reference points and concept stimulators. The idea behind the piece, the physical activity involved in making it, and the product itself, all may be seen to amplify, modify, and parody one another.</h4

Identification of RecQL1 as a Holliday junction processing enzyme in human cell lines

Homologous recombination provides an effective way to repair DNA double-strand breaks (DSBs) and is required for genetic recombination. During the process of homologous recombination, a heteroduplex DNA structure, or a ‘Holliday junction’ (HJ), is formed. The movement, or branch migration, of this junction is necessary for recombination to proceed correctly. In prokaryotes, the RecQ protein or the RuvA/RuvB protein complex can promote ATP-dependent branch migration of Holliday junctions. Much less is known about the processing of Holliday junctions in eukaryotes. Here, we identify RecQL1 as a predominant ATP-dependent, HJ branch migrator present in human nuclear extracts. A reduction in the level of RecQL1 induced by RNA interference in HeLa cells leads to an increase in sister chromatid exchange. We propose that RecQL1 is involved in the processing of Holliday junctions in human cells