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The mcrB (rglB) locus of Escherichia coli K-12 mediates sequence-specific restriction of cytosine-modifled DNA. Genetic and sequence analysis shows that the locus actually comprises two genes, mcrB and mcrC. We show here that in vivo, McrC modifies the specificity of McrB restriction by expanding the range of modified sequences restricted. That is, the sequences sensitive to McrB+-dependent The locus known as mcrB was one of the first restriction systems to be discovered (33), by virtue of its action on special variants of T-even bacteriophage that incorporate 5-hydroxymethylcytosine (hm`C) into their DNA without further modification (see reference 50 for a review). This locus, formerly known as rglB (or r2,4) (48), was rediscovered because of difficulties encountered in cloning the genes for site-specific modification methylases associated with type II restriction-modification systems (7,26,40,49). In addition to hm5C-DNA, many but not all sequences methylated by site-specific cytosine modification methylases are restricted by the system in vivo, and the consensus recognition sequence 5'GmC was proposed (49). McrB is thus a sequence-specific, modification-requiring restriction system. We show here that the mcrB locus described above actually comprises two genes and that both are required for restriction of most the sequences previously characterized as sensitive. Thus, we will refer to the complete system as the McrBC system.The genes encoding the system are contained within the immigration control region of the Escherichia coli K-12 genome. Three restriction systems are encoded within 14 kilobases (kb) here (48). The well-studied hsdRMS locus (20, 31, 55) encodes the multisubunit type I system EcoK, which recognizes a seven-base sequence and cleaves the target when the sequence is not modified. The other two systems are the flanking loci mcrBC, described above, and mrr, which mediates site-specific restriction of adenine-modified DNA (22). The sequence organization of this region, judged by Southern blot analysis of chromosomal DNA, is highly variable in enteric bacteria (12), both in the hsd genes specifically and in the flanking sequences. Sequence analysis presented here is consistent with recent acquisition of the mcrBC genes by E. coli, possible accounting for some of the observed variability. * Corresponding author.At the molecular level, restriction systems consist of sequence-specific double-stranded endonucleases, usually accompanied by a sequence-specific modification methylase. So far, four classes of endonucleases have been described. The simplest are the type II enzymes, in which the endonuclease and protective methylase activities reside in separate enzymes. These endonucleases typically act as dimers of identical subunits and require only Mg2" for activity (38).One group of type II isoschizomers, typified by DpnI, recognizes a modified site (28), as McrBC appears to do. In contrast, type I and type III enzymes have separate specificity subunits that recognize the DNA site and require ATP in a...

Shifting Burdens explores the process and features of mental patient deinstitutionalization as it occurred in America in the 1950s and 1960s. This paper examines the disillusionments American society had with mental institutions, such as faltering standards of care, staff failures, and inadequate treatment options. These issues resulted in the movement towards deinstitutionalization, resulting in the burden of care for displaced mental patients being shifted onto community homes and patients families. Shifting Burdens challenges the notion that deinstitutionalization at the time was a successful endeavour, as the question of care for mental patients continues to exist today.

The articles published in our Winter 2016 edition are connected loosely under the themes of pop culture and public memory. Our annual conference, held in late April, featured Dr. Kelly MacFarlane as our keynote lecture to speak on the interplay between history, public memory, and pop culture. We are thrilled to present to you eight excellent articles in our Winter 2016 edition: An ideological examination of the US-Russian Space Race and public memory of the event during the cold war is offered in "Narrative Memory in the Space Race"; The article "The Swastika and the Maple Leaf: National-socialism and anti-semitism in Canada" returns to the 1930s to explore anti-semitist ideologies in our country preceeding the second world war;"The Monumentalization of our Disgrace" is a captivating look at the manner in which concentration and death camps standing after the Holocaust are memorialized today and the local residents' public perception of such memorials; "Hegemony without Tears: Defenitions and uses of hegemony from Gramsci onwards" explores the works of Marxist writer Antonio Gramsci and his influence upon other writers through several case studies, ultimately commenting on the subsequent reinterpretation of Gramsci's definition of hegemony; "Confrontation and Cooperation: the hidden history of national parks and Indigenous groups in Canada" takes the reader through a historical analysis of Canada's national parks and the indigenous groups originally inhabiting them, arguing the erasure of these groups by the National Parks system; "War and Faith: Memories of the Great Patriotic War in the Russian Orthodox church" examines the Church's modern conceptualization of the Soviet Union as a "holy battle for survival; "Administering State Legislation: The kirk and witchcraft in early modern Scotland" is a fascinating look at the relationship between the duties performed by the Royal Court and the Calivinist church in Scotland; and finally, we have "The Limits of Rationalism: Early modern geography and the idea of Europe", an investigation of cartogropher's contributions in the 16th and 17th century towards the concept of 'Europe' and the growth of a scientific worldview. We wholly hope you enjoy our Winter 2016  edition as much as our staff has enjoyed curating it. Editors Emily Kaliel Ellen Sutherland Assistant Editors Jean Middleton Kayla Pituka Senior Reviewers Kyler Chittick Emily Hoven Katarina Hoven Faculty Advisor Jeremy Caradonna

This year, Constellations is pleased to welcome two new editors and an entirely new senior review board. This transition has resulted in an exciting new demographic of individuals responsible for the production of this edition: our 2015/2016 senior review board is composed of students majoring from history to philosophy to native studies, all of whom come together under their love for historiographical research. Our Fall 2015 edition reflects the diverse nature of our student staff. We begin our edition in the 1600s with Nicholas Smit-Keding's "'Absurd' Rationalist Cosmology: Copernicus, Kepler, Descartes and the Religious Basis for the end to Aristotelian Dogma" offers a historical look at the shift from the Aristotelian geocentric model to the heliocentric model, a critical moment in scientific history. From there, we travel back to the time of Nero in Faisal Afridi's "Defense of Nero in the Style of Seneca and Genre of Biography", an entirely new type of publication to Constellations: this article presents its defense of Nero in the form of a narrative, as written from Nero's tutor Seneca. Our third article, Letitia Johnson's "Gender and Medical Inspections at Ellis Island" is the most historically recent of our fall edition and offers a critical examination of the difficulties of immigrants as they passed over the American boarder in the late 19 th and early 20 th century. Finally, we move to the Ottoman Empire in Thisaranie Herath's "Women and Orientalism: 19th century Representations of the Harem by European female travellers and Ottoman women", offering a rethinking of the depiction of the Harem space as a cross-cultural dialogue. We wholly hope you enjoy our Fall 2015 edition as much as our staff has enjoyed curating it.