Exact solution of a 2D interacting fermion model

We study an exactly solvable quantum field theory (QFT) model describing interacting fermions in 2+1 dimensions. This model is motivated by physical arguments suggesting that it provides an effective description of spinless fermions on a square lattice with local hopping and density-density interactions if, close to half filling, the system develops a partial energy gap. The necessary regularization of the QFT model is based on this proposed relation to lattice fermions. We use bosonization methods to diagonalize the Hamiltonian and to compute all correlation functions. We also discuss how, after appropriate multiplicative renormalizations, all short- and long distance cutoffs can be removed. In particular, we prove that the renormalized two-point functions have algebraic decay with non-trivial exponents depending on the interaction strengths, which is a hallmark of Luttinger-liquid behavior.Comment: 59 pages, 3 figures, v2: further references added; additional subsections elaborating mathematical details; additional appendix with details on the relation to lattice fermion

Lymphedema, musculoskeletal events and arm function in older patients receiving adjuvant chemotherapy for breast cancer (Alliance A171302)

Purpose: Musculoskeletal events (MEs) resulting from breast cancer treatment can significantly interfere with the quality of life (QOL) of older adults. We evaluated the incidence of MEs in women 65 years and older who had surgery and adjuvant chemotherapy for breast cancer, and the impact of treatment on MEs and arm function. Patients and methods: Patient-reported data in Alliance/CALGB 49907 were collected using the EORTC QLQ-BR23 and physician-reported adverse events to characterize self-reported MEs and incidence of lymphedema. EORTC QLQ-BR23 items related to musculoskeletal events were analyzed in this study and data collected at study entry (post-operative) and 12 and 24 months post-entry. Results: Lymphedema, arm function, and ME data were available for 321 patients. One or more MEs were reported by 87% (median number = 3) and 64% (median number = 1) of patients post-operatively and at 24 months. At 24 months 2% had persistence of six MEs. Seventy-four percent experienced at least ≥3/6 types of MEs over the 24-month period. Detection of lymphedema at any time during the study was noted in 7.5% of the patients and appeared to be associated with the type of chemotherapy given: CMF 16.4%, capecitabine 5.8%, and AC 4%. Mastectomy and axillary node dissection were associated with the most MEs. LROM correlated with poorer arm function at all time periods. Conclusion: Potentially debilitating MEs occur in three-fourths of elderly women undergoing standard therapy for breast cancer. Emphasis should be placed on prevention, identification, and treatment of these MEs to improve QOL

Genotype-Phenotype Correlation in NF1: Evidence for a More Severe Phenotype Associated with Missense Mutations Affecting NF1 Codons 844–848

Neurofibromatosis type 1 (NF1), a common genetic disorder with a birth incidence of 1:2,000–3,000, is characterized by a highly variable clinical presentation. To date, only two clinically relevant intragenic genotype-phenotype correlations have been reported for NF1 missense mutations affecting p.Arg1809 and a single amino acid deletion p.Met922del. Both variants predispose to a distinct mild NF1 phenotype with neither externally visible cutaneous/plexiform neurofibromas nor other tumors. Here, we report 162 individuals (129 unrelated probands and 33 affected relatives) heterozygous for a constitutional missense mutation affecting one of five neighboring NF1 codons—Leu844, Cys845, Ala846, Leu847, and Gly848—located in the cysteine-serine-rich domain (CSRD). Collectively, these recurrent missense mutations affect ∼0.8% of unrelated NF1 mutation-positive probands in the University of Alabama at Birmingham (UAB) cohort. Major superficial plexiform neurofibromas and symptomatic spinal neurofibromas were more prevalent in these individuals compared with classic NF1-affected cohorts (both p < 0.0001). Nearly half of the individuals had symptomatic or asymptomatic optic pathway gliomas and/or skeletal abnormalities. Additionally, variants in this region seem to confer a high predisposition to develop malignancies compared with the general NF1-affected population (p = 0.0061). Our results demonstrate that these NF1 missense mutations, although located outside the GAP-related domain, may be an important risk factor for a severe presentation. A genotype-phenotype correlation at the NF1 region 844–848 exists and will be valuable in the management and genetic counseling of a significant number of individuals

The evolving SARS-CoV-2 epidemic in Africa: Insights from rapidly expanding genomic surveillance

INTRODUCTION Investment in Africa over the past year with regard to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) sequencing has led to a massive increase in the number of sequences, which, to date, exceeds 100,000 sequences generated to track the pandemic on the continent. These sequences have profoundly affected how public health officials in Africa have navigated the COVID-19 pandemic. RATIONALE We demonstrate how the first 100,000 SARS-CoV-2 sequences from Africa have helped monitor the epidemic on the continent, how genomic surveillance expanded over the course of the pandemic, and how we adapted our sequencing methods to deal with an evolving virus. Finally, we also examine how viral lineages have spread across the continent in a phylogeographic framework to gain insights into the underlying temporal and spatial transmission dynamics for several variants of concern (VOCs). RESULTS Our results indicate that the number of countries in Africa that can sequence the virus within their own borders is growing and that this is coupled with a shorter turnaround time from the time of sampling to sequence submission. Ongoing evolution necessitated the continual updating of primer sets, and, as a result, eight primer sets were designed in tandem with viral evolution and used to ensure effective sequencing of the virus. The pandemic unfolded through multiple waves of infection that were each driven by distinct genetic lineages, with B.1-like ancestral strains associated with the first pandemic wave of infections in 2020. Successive waves on the continent were fueled by different VOCs, with Alpha and Beta cocirculating in distinct spatial patterns during the second wave and Delta and Omicron affecting the whole continent during the third and fourth waves, respectively. Phylogeographic reconstruction points toward distinct differences in viral importation and exportation patterns associated with the Alpha, Beta, Delta, and Omicron variants and subvariants, when considering both Africa versus the rest of the world and viral dissemination within the continent. Our epidemiological and phylogenetic inferences therefore underscore the heterogeneous nature of the pandemic on the continent and highlight key insights and challenges, for instance, recognizing the limitations of low testing proportions. We also highlight the early warning capacity that genomic surveillance in Africa has had for the rest of the world with the detection of new lineages and variants, the most recent being the characterization of various Omicron subvariants. CONCLUSION Sustained investment for diagnostics and genomic surveillance in Africa is needed as the virus continues to evolve. This is important not only to help combat SARS-CoV-2 on the continent but also because it can be used as a platform to help address the many emerging and reemerging infectious disease threats in Africa. In particular, capacity building for local sequencing within countries or within the continent should be prioritized because this is generally associated with shorter turnaround times, providing the most benefit to local public health authorities tasked with pandemic response and mitigation and allowing for the fastest reaction to localized outbreaks. These investments are crucial for pandemic preparedness and response and will serve the health of the continent well into the 21st century

Perspectives on ‘the lens of risk’ interview series: interviews with Tom Horlick-Jones, Paul Slovic and Andy Alaszewski

This article is the fourth and final of an interview series with a selection of significant contributors to the social science of risk. It provides quasi-verbatim interviews with Tom Horlick-Jones, Paul Slovic and Andy Alaszewski. Tom Horlick-Jones contributed to Chapter 6 of the Royal Society Risk monograph, on risk management. He offers further insights into the debates which underlay its production to those given by Nick Pidgeon in the first article of this series. Paul Slovic provides a North American perspective on risk social science. Andy Alaszewski, in the last of the eight interviews, discusses his views about risk in relation to the evolution of his journal, Health, Risk & Society

Researching the social impact of the arts : literature, fiction and the novel

This paper offers a contribution to current debates in the field of cultural policy about the social impact of the arts. It explores the conceptual difficulties that arise in the notion of ‘the arts’ and the implications of these difficulties for attempts to generalise about their value, function and impact. It considers both ‘essentialist’ and ‘institutional’ perspectives, first on ‘the arts’ in toto and then on literature, fiction and the novel with the view of making an innovative intellectual connection between aesthetic theories and contemporary cultural policy discourse. The paper shows how literature sits uneasily in the main systems of classifying the arts and how the novel and fiction itself are seen as problematic categories. The position of the novel in the literary canon is also discussed, with particular reference to the shifting instability of the canon. The paper suggests that the dilemmas thrown up in trying to define or classify the novel are likely to be encountered in attempting to define other art forms. The implications of these findings for the interpretation and conduct of traditional ‘impact studies’ are explored