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Archaeologists evince a strong tendency to impute significance to the material traces they study, a propensity that has been especially marked since the post-processual emphasis on meaning and that has taken on renewed vigour with the turn to materiality. But are there not situations in which things are rather incidental or insignificant? This set of essays emerged from a workshop held in Berlin in April 2018, in which a group of scholars was invited to discuss the place of the incidental in social life in general and in archaeology in particular. Rather than lengthy formal papers, we offer an introduction that presents a general set of reflections on the issue of the incidentalness of things, followed by essays that pursue particular directions raised by that introduction as well as our discussions in Berlin. It is our hope that these brief forays into a complex topic will stimulate further work on this subject.
Background: Adults are at risk of being exposed to influenza from many sources. Healthcare personnel (HCP) have the additional risk of being exposed to ill patients.
To determine whether HCP were at higher risk than adults working in nonhealthcare roles (non-HCP).
Prospective cohort study.
Acute-care hospitals and other businesses in Toronto, Ontario, Canada.
Adults aged 18–69 years were enrolled for 1 or more of the 2010/2011, 2011/2012, and 2012/2013 influenza seasons. Swabs collected during acute respiratory illnesses were tested for influenza and pre- and postseason blood samples were tested for influenza-specific immune response.
The adjusted odds of influenza were similar for HCP and non-HCP (odds ratio [OR], 1.29; 95% confidence interval [CI], 0.63–2.63). Older adults and those vaccinated against influenza had lower odds, and those who shared their workspace and who used corrective eyewear had higher odds of influenza.
HCP and other working adults are at similar risk of influenza infection.
Identical and fraternal twin pairs reared together have been key to understanding the genetic and environmental etiology of dyslexia and of individual differences in reading. In this chapter, we begin with a brief overview of the methods of twin research, and the historical development and application of these methods to understanding the etiology of individual differences and deficits in reading and related skills. Then we examine results from predominantly English-language twin research on dyslexia. The next section on twin studies of individual differences in reading ability introduces a broader cross-language perspective that includes comparisons of findings from studies in the United States, the United Kingdom, Australia, Norway, Sweden, the Netherlands, and China. Then we expand the reading phenotype beyond word recognition to reading comprehension, the ultimate goal of reading.
The English auxiliary system exhibits many lexical exceptions and subregularities, and considerable dialectal variation, all of which are frequently omitted from generative analyses and discussions. This paper presents a detailed, movement-free account of the English Auxiliary System within Sign-Based Construction Grammar (Sag 2010, Michaelis 2011, Boas & Sag 2012) that utilizes techniques of lexicalist and construction-based analysis. The resulting conception of linguistic knowledge involves constraints that license hierarchical structures directly (as in context-free grammar), rather than by appeal to mappings over such structures. This allows English auxiliaries to be modeled as a class of verbs whose behavior is governed by general and class-specific constraints. Central to this account is a novel use of the feature aux, which is set both constructionally and lexically, allowing for a complex interplay between various grammatical constraints that captures a wide range of exceptional patterns, most notably the vexing distribution of unstressed do, and the fact that Ellipsis can interact with other aspects of the analysis to produce the feeding and blocking relations that are needed to generate the complex facts of EAS. The present approach, superior both descriptively and theoretically to existing transformational approaches, also serves to undermine views of the biology of language and acquisition such as Berwick et al. (2011), which are centered on mappings that manipulate hierarchical phrase structures in a structure-dependent fashion.
Because of rapid solidification involved in the laser or e-beam based additive manufacturing (AM) process, solution treatable metallic parts made by these methods usually possess a unique nonequilibrium microstructure which changes significantly during subsequent thermal treatment. Such evolution alters the size, morphology, length scale, and distribution of microstructural features and has a substantial impact on thermal properties and possibly on electrical properties as well. This study focuses on effects of microstructural evolution on thermal properties of an additively manufactured AlSi10Mg part. The changes of thermal properties such as thermal expansion, heat capacity, thermal diffusivity, and thermal conductivity as a function of thermal treatment are reported. The results show that the formation of supersaturated primary α aluminum and unique cellular structure imparted by fast solidification in the AM process are the major cause for the low thermal diffusivity and low thermal conductivity observed in this solution treatable, as-built part. A correlation between microstructural evolution and changes in thermal properties is established. Advantages and tailoring of the thermal properties of additively built parts are discussed. Implications of these results are important for other additively manufactured components based on popular solution treatable alloys.
Gray matter (GM) ‘pseudoatrophy’ is well-documented in patients with anorexia nervosa (AN), but changes in white matter (WM) are less well understood. Here we investigated the dynamics of microstructural WM brain changes in AN patients during short-term weight restoration in a combined longitudinal and cross-sectional study design.
Diffusion-weighted images were acquired in young AN patients before (acAN-Tp1, n = 56) and after (acAN-Tp2, n = 44) short-term weight restoration as well as in age-matched healthy controls (HC, n = 60). Images were processed using Tract-Based-Spatial-Statistics to compare fractional anisotropy (FA) across groups and timepoints.
In the cross-sectional comparison, FA was significantly reduced in the callosal body in acAN-Tp1 compared with HC, while no differences were found between acAN-Tp2 and HC. In the longitudinal arm, FA increased with weight gain in acAN-Tp2 relative to acAN-Tp1 in large parts of the callosal body and the fornix, while it decreased in the right corticospinal tract.
Our findings reveal that dynamic, bidirectional changes in WM microstructure in young underweight patients with AN can be reversed with brief weight restoration therapy. These results parallel those previously observed in GM and suggest that alterations in WM in non-chronic AN are also state-dependent and rapidly reversible with successful intervention.
We develop a theory of electoral competition in multidistrict legislative elections when nomination decisions are made by local policy-motivated party members, and voters care about both local and national positions. We show that the asymmetry generated by different national party positions reduces or even entirely removes the competitive pressure to nominate moderate candidates. The model has important implications for our understanding of policy divergence and, in particular, of the effects of gerrymandering.
The powder-bed laser additive manufacturing (AM) process is widely used in the fabrication of three-dimensional metallic parts with intricate structures, where kinetically controlled diffusion and microstructure ripening can be hindered by fast melting and rapid solidification. Therefore, the microstructure and physical properties of parts made by this process will be significantly different from their counterparts produced by conventional methods. This work investigates the microstructure evolution for an AM fabricated AlSi10Mg part from its nonequilibrium state toward equilibrium state. Special attention is placed on silicon dissolution, precipitate formation, collapsing of a divorced eutectic cellular structure, and microstructure ripening in the thermal annealing process. These events alter the size, morphology, length scale, and distribution of the beta silicon phase in the primary aluminum, and changes associated with elastic properties and microhardness are reported. The relationship between residual stress and silicon dissolution due to changes in lattice spacing is also investigated and discussed.
Pseudoelastic NiTi-based shape-memory alloys (SMAs) have recently received attention as candidate materials for solid-state refrigeration. The elastocaloric effect in SMAs exploits stress-induced martensitic transformation, which is associated with large latent heat. Most importantly, cyclic mechanical loading/unloading provides large adiabatic temperature drops exceeding 25 K at high process efficiencies. This article summarizes the underlying principles, important material parameters and process requirements, and reviews recent progress in the development of pseudoelastic SMAs with large coefficients of performance, as well as very good functional fatigue resistance. The application potential of SMA film and bulk materials is demonstrated for the case of cyclic tensile loading/unloading in prototypes ranging from miniature-scale devices to large-scale cooling units.
Maternal vitamin D deficiency may increase risk of autism spectrum disorder (ASD), but direct evidence is lacking.
To clarify the relationship between maternal vitamin D deficiency and offspring risk of ASD with and without intellectual disability.
Using a register-based total population study (N=509 639), we calculated adjusted odds ratios (aORs) and 95% confidence intervals (CIS) of ASD with and without intellectual disability in relation to lifetime diagnoses of maternal vitamin D deficiency. Although rare, such deficiency was associated with offspring risk of ASD with, but not without, intellectual disability (aORs 2.51, 95% CI 1.22–5.16 and 1.28, 0.68–2.42). Relationships were stronger in non-immigrant children.
If reflecting associations for prenatal hypovitaminosis, these findings imply gestational vitamin D substitution as a means of ASD prevention.
The 1994 sale of radio spectrum for “personal communication services” (PCS) marked a sharp change in policy by the US Federal Communications Commission (FCC). Before turning to auctions the FCC had allocated valuable spectrum on the basis of comparative hearings (also known as “beauty contests”) and lotteries. Nobel laureate Ronald Coase long advocated that market-based mechanisms would improve the allocation of scarce spectrum resources, but his early insights were ignored for decades . The PCS auction raised over six hundred million dollars for the US treasury and it was widely considered a success. Several authors discuss the advantages and disadvantages of auctions and beauty contests for allocating scarce spectrum [2, 3, 4]. For example, some argue that financially strong bidders might have advantages over weaker bidders in an auction, while others argue that with efficient capital markets such differences should be less of a concern. Nowadays, spectrum is predominantly assigned by auction, both in the US and elsewhere [5, 6], and in this paper we focus on questions of auction design.
The simultaneous multi-round auction (SMRA), which was designed for the US FCC in the early 90's has been the standard auction format for selling spectrum world wide for many years. It auctions multiple licenses for sale in parallel and uses simple activity rules which forces bidders to be active from the start. Despite the simplicity of its rules there can be considerable strategic complexity in the SMRA when there are synergies between licenses that cover adjacent geographic regions or between licenses in different frequency bands. Bidders who compete aggressively for a certain combination of licenses risk being exposed when they end up winning an inferior subset at high prices. When bidders rationally anticipate this exposure problem, competition will be suppressed with adverse consequences for the auction's performance. The exposure problem has led auction designers to consider combinatorial auctions, which enable bidders to express their preferences for an entire set of licenses directly. In fact, the design of spectrum auctions is seen as a pivotal problem im multi-object auction design and successful solutions are a likely role-model for other public or private sector auctions such as transportation or industrial procurement.
Since 2008, the combinatorial clock auction (CCA) has been used by regulators in various countries such as the Austria, Australia, Canada, Denmark, Ireland, the Netherlands, and Switzerland to sell spectrum.
Prodiamine is a dinitroaniline herbicide labeled for PRE control of goosegrass in warm- and cool-season turfgrass. In 2013, several golf course roughs in Maryville, TN reported poor goosegrass control (< 20%) following prodiamine treatment at 1,120 g ai ha-1. We harvested suspected prodiamine-resistant (PR) and prodiamine-susceptible (S) goosegrass phenotypes from the field and exposed them to a range of increasing prodiamine concentrations in hydroponic culture. Exposure to prodiamine at 0.001 mM reduced root growth of the S phenotype to 11% of the non-treated check. By comparison, exposure to 0.001 mM prodiamine had minimal effect on the PR phenotype, as root growth was 94% of the non-treated check. Molecular analyses revealed that PR plants contained a threonine (Thr) to isoleucine (Ile) substitution at position 239 on the α-tubulin 1 (TUA1) protein. The substitution, found in all PR plants, is the mechanism of prodiamine resistance in this phenotype. In field studies, topramezone controlled PR goosegrass 72% to 89% by 50 d after treatment (DAT) compared to only 22% to 23% for foramsulfuron. Topramezone treatment injured bermudagrass 34% to 60% from 7 to 14 DAT; however, injury was≤6% 28 DAT and 0% by the end of the study. Our results indicate that POST applications of topramezone can control dinitroaniline-resistant goosegrass. In addition, we established an easy-to-use genotyping assay to quickly screen goosegrass phenotypes for a target-site mutation (Thr-239-Ile) on TUA1 associated with resistance to dinitroaniline herbicides such as prodiamine. Future research should work to expand this assay for use with other weed species and herbicidal modes of action.
Disjunctive Answer Set Programming is a powerful declarative programming paradigm with complexity beyond NP. Identifying classes of programs for which the consistency problem is in NP is of interest from the theoretical standpoint and can potentially lead to improvements in the design of answer set programming solvers. One of such classes consists of dual-normal programs, where the number of positive body atoms in proper rules is at most one. Unlike other classes of programs, dual-normal programs have received little attention so far. In this paper we study this class. We relate dual-normal programs to propositional theories and to normal programs by presenting several inter-translations. With the translation from dual-normal to normal programs at hand, we introduce the novel class of body-cycle free programs, which are in many respects dual to head-cycle free programs. We establish the expressive power of dual-normal programs in terms of SE- and UE-models, and compare them to normal programs. We also discuss the complexity of deciding whether dual-normal programs are strongly and uniformly equivalent.
Cardiovascular imagers are faced with the challenge of interpreting cases that include artifacts, unusual findings, or anatomic variants on an almost daily basis. These studies can result in confusion and may lead to misdiagnosis even for the most experienced imager. This book provides an approachable reference for practising cardiovascular imagers to aid with both commonly and uncommonly encountered entities that can result in inappropriate patient management. Through the focused use of case examples, this book reviews 100 conditions that can be seen in clinical practice, including pseudotumors, artifacts, anatomic variants, mimics, and unusual diagnoses. Each highly illustrated case follows a standard format, allowing readers to learn from real-life examples and provides an accessible and rapid source of reference for the improved interpretation of cardiovascular imaging and enhanced patient care. This text will be invaluable to radiologists, cardiologists, and trainees.