Twisted C*-algebras associated to finitely aligned higher-rank graphs

We introduce twisted relative Cuntz-Krieger algebras associated to finitely aligned higher-rank graphs and give a comprehensive treatment of their fundamental structural properties. We establish versions of the usual uniqueness theorems and the classification of gauge-invariant ideals. We show that all twisted relative Cuntz-Krieger algebras associated to finitely aligned higher-rank graphs are nuclear and satisfy the UCT, and that for twists that lift to real-valued cocycles, the K-theory of a twisted relative Cuntz-Krieger algebra is independent of the twist. In the final section, we identify a sufficient condition for simplicity of twisted Cuntz-Krieger algebras associated to higher-rank graphs which are not aperiodic. Our results indicate that this question is significantly more complicated than in the untwisted setting.Comment: Version 2: This paper has now appeared in Documenta Mathematica. This version on arXiv exactly matches the pagination and format of the published version. Original published version available from http://www.math.uni-bielefeld.de/documenta/vol-19/28.htm

Repairing Infrastructures

An investigation of the causes and consequences of the strange, ambivalent, and increasingly central role of infrastructure repair in modern life. Infrastructures—communication, food, transportation, energy, and information—are all around us, and their enduring function and influence depend on the constant work of repair. In this book, Christopher Henke and Benjamin Sims explore the causes and consequences of the strange, ambivalent, and increasingly central role of infrastructure repair in modern life. Henke and Sims offer examples, from local to global, to investigate not only the role of repair in maintaining infrastructures themselves but also the social and political orders that are created and sustained through them. Repair can encompass not only the kind of work we most commonly associate with the term but also any set of practices aimed at restoring a sense of normalcy or credibility to the places and institutions we inhabit in everyday life. From cases as diverse as the repair of building systems on a university campus, a conflict over retrofitting a bridge while protecting murals painted on it, and the global challenge posed by climate change, Henke and Sims assemble a range of examples to illustrate key conceptual points about the role of repair. They show that repair is an essential if often overlooked aspect of understanding the broader impact and politics of infrastructures. Understanding repair helps us better understand infrastructures and the scope of their influence on our lives

Emittance Mapping in rf Guns

This paper discusses the trends and trade-offs between transverse {\sigma}x and longitudinal {\sigma}z bunch dimensions, rf injector gradient, bunch charge, and intrinsic electron mean transverse energy (MTE), where all can be chosen to be independent, and the resulting effects on emittance and transverse brightness. Using a practical example of a quarter wave normal conducting photoinjector, it is computationally found that regardless of MTE and bunch charge, there is a universal relation between the gradient E and the aspect ratio of the bunch ({\sigma}x/{\sigma}z ) leading to the highest brightness. This computational result is understood using an analytical formalism consisting of K J Kim's emittance formulation and a two-dimensional space charge model. The results, obtained computationally and interpreted in a robust physical framework, could therefore provide the basis for an express mapping approach for emittance forecasting when used with practical injector system design requirements and limitations

Good housekeeping: Safety and order in the scientific laboratory

Laboratory safety might not seem, at first, to be very profoundly related to scientific knowledge. Of course safety is a relatively trivial issue in many scientific settings, especially in comparison to the kind of safety concerns found, say, at a construction site or a chemical plant. However, as scientific work has come to involve more exotic chemicals, biological organisms, and forms of radiation, and generally become more industrial in character, safety has become more of a concern. This has occurred alongside a general expansion of government regulation of workplace safety during the 20thc entury, and a recent trend toward extending work lace safety efforts to new kinds of work, including administrative and professional tasks. As a result of these trends, scientists find that they are increasingly being held responsible for following safety regulations in their re{approx}ear

Papers Read At a Session of the Twenty-First Annual Meeting of the Southern Historical Association, Memphis Tennessee. November 10,1955

MS/134 Civil Rights Papers. Segregation, Jim Crow, 1950s, US South, Southern States, American South Scanned from original prints. Processed by Dallas Suttles ([email protected]) on 6/21/2016. 600 DPI. OCR Abbyy FineReader 11.0. Pages cropped to size.Three Views of the Segregation Decisions Papers Read At a Session of the Twenty-First Annual Meeting of the Southern Historical Association, Memphis Tennessee. November 10,1955 by William Faulkner, Benjamin Mays, Cecil Sims. Introduction by Bell Wiley. Significant because of essay by Faulkner, but Benjamin Mays is often called the spiritual mentor of Martin Luther King, Jr. Important document showing how prominent Southerners viewed early Court decisions concerning desegregation and how they viewed the future

Tumor-associated T cell receptor repertoires in low- and high-grade gliomas

Glioblastoma (GBM) remains prognostically dismal, with care centered on resection, motivating research into novel therapies. Although inducing anti-tumor immunity remains an attractive target for therapeutic and preventative intervention, the interplay between evolving dysregulation of the glioma microenvironment and T cell inefficacy remains poorly understood. In our murine model of proneural glioma, retroviral delivery of PDGF and cre-mediated knockout of PTEN in glial progenitors of adult C57BL/6 gives rise to slow-growing tumors, which were harvested at early- mid- and late-stage progression timepoints following induction, along with peripheral blood. From human patients, tissue from low- and high-grade glioma resections and corresponding peripheral lymphocytes were cryofrozen during surgery at New York Presbyterian-CUMC. For both species, we employed a commercially available primer set (iRepertoire) for nested PCR of the complementarity-determining region 3 (CDR3) of the TCR-alpha and TCR-beta chains from the T cell RNA, followed by next-generation sequencing on an Illumina MiSeq. We developed a computational pipeline for mapping TCR cassettes, in silico translation, pairwise analysis of tissue/periphery per subject, and error analysis. In the murine model, we observe that at late-stage, the intratumoral TCR repertoire diverges significantly from the peripheral, including dramatic expansion of single tumor-associated CDR3s, while the peripheral repertoire itself diverges from those of healthy mice. In both human patients and mice, we observed tumor-associated CDR3s, disproportionately abundant in tumor tissue compared to the corresponding peripheral blood, at both the amino acid and nucleotide level. In human samples we observed tumor-specific TCR expansions that were associated with particular functional subsets (CD8+, CD4+, Treg, NKT). Sequence-level study of the TCR repertoire promises new insight into the scope of glioma immunosuppression, especially systemic effects which remain elusive and the origins of intratumoral suppressive populations, and holds the potential for immunotherapeutic interventions, non-invasive diagnostics, and direct assessment of global responses to immunotherapy