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How to Directly Measure Floquet Topological Invariants in Optical Lattices
No full textThe classification of topological Floquet systems with time-periodic Hamiltonians transcends that of static systems. For example, spinless fermions in periodically driven two-dimensional lattices are not completely characterized by the Chern numbers of the quasienergy bands, but rather by a set of winding numbers associated with the gaps. We propose a feasible scheme for measuring these winding numbers in a periodically driven optical lattice efficiently and directly. It is based on the construction of a one-parameter family of drives, continuously connecting the Floquet system of interest to a trivial reference system. The winding numbers are then determined by the identification and the tomography of the band-touching singularities occurring on the way. As a by-product, we also propose a method for probing spectral properties of time evolution operators via a time analog of crystallography
Stand Up, Show Respect: Athlete Activism, Nationalistic Attitudes, and Emotional Response
No full textThe number of athlete social protests has risen over the past several years, but no protest has touched a collective national nerve as kneeling for the national anthem has. Using the theoretical framework of social identity theory, this study examined how nationalistic attitudes affect participants’ perceptions of athletes who engage in a form of activism. A 2 × 3 between-subjects factorial design was used for a manipulated newspaper article focusing on the issue of a college quarterback kneeling for the national anthem. Results found no significant effects with respect to implicit and explicit racial cues. Data did support the notion that individuals who displayed higher levels of nationalism would respond with more negative emotions to the athlete activism. On a theoretical level, this study lends support to the ideas of social identity theory and social identity threat management. Broader social and practical implications are also discussed
Neural organization of speech production: A lesion-based study of error patterns in connected speech
No full textWhile numerous studies have explored single-word naming, few have evaluated the behavioral and neural correlates of more naturalistic language, like connected speech, which we produce every day. Here, in a retrospective analysis of 120 participants at least six months following left hemisphere stroke, we evaluated the distribution of word errors (paraphasias) and associated brain damage during connected speech (picture description) and object naming. While paraphasias in connected speech and naming shared underlying neural substrates, analysis of the distribution of paraphasias suggested that lexical-semantic load is likely reduced during connected speech. Using voxelwise lesion-symptom mapping (VLSM), we demonstrated that verbal (real word: semantically related and unrelated) and sound (phonemic and neologistic) paraphasias during both connected speech and naming loaded onto the left hemisphere ventral and dorsal streams of language, respectively. Furthermore, for the first time using both connected speech and naming data, we localized semantically related paraphasias to more anterior left hemisphere temporal cortex and unrelated paraphasias to more posterior left temporal and temporoparietal cortex. The connected speech results, in particular, highlight a gradient of specificity as one translates visual recognition from left temporo-occipital cortex to posterior and subsequently anterior temporal cortex. The robustness of VLSM results for sound paraphasias derived during connected speech was notable, in that analyses performed on sound paraphasias from the connected speech task, and not the naming task, demonstrated significant results following removal of lesion volume variance and related apraxia of speech variance. Therefore, connected speech may be a particularly sensitive task on which to evaluate further lexical-phonological processing in the brain. The results presented here demonstrate the related, though different, distribution of paraphasias during connected speech, confirm that paraphasias arising in connected speech and single-word naming likely share neural origins, and endorse the need for continued evaluation of the neural substrates of connected speech processes
Overview of HOMEChem: House Observations of Microbial and Environmental Chemistry
No full textThe House Observations of Microbial and Environmental Chemistry (HOMEChem) study is a collaborative field investigation designed to probe how everyday activities influence the emissions, chemical transformations and removal of trace gases and particles in indoor air. Sequential and layered experiments in a research house included cooking, cleaning, variable occupancy, and window-opening. This paper describes the overall design of HOMEChem and presents preliminary case studies investigating the concentrations of reactive trace gases, aerosol particles, and surface films. Cooking was a large source of VOCs, CO, NO, and particles. By number, cooking particles were predominantly in the ultrafine mode. Organic aerosol dominated the submicron mass, and, while variable between meals and throughout the cooking process, was dominated by components of hydrocarbon character and low oxygen content, similar to cooking oil. Air exchange in the house ensured that cooking particles were present for only short periods. During unoccupied background intervals, particle concentrations were lower indoors than outdoors. The cooling coils of the house ventilation system induced cyclic changes in water soluble gases. Even during unoccupied periods, concentrations of many organic trace gases were higher indoors than outdoors, consistent with housing materials being potential sources of these compounds to the outdoor environment. Organic material accumulated on indoor surfaces, and exhibited chemical signatures similar to indoor organic aerosol
Young adult US-born Latina women's thoughts, feelings and beliefs about unintended pregnancy
No full textCurrent measures of unintended pregnancy underestimate the co-occurring, complex set of social, cultural, economic and structural factors that influence how women interpret unintended pregnancy. The purpose of this study was to prospectively explore young adult US-born Latinas’ thoughts, feelings and beliefs about pregnancy, specifically unintended pregnancies and the sociocultural factors identified as contributors to those beliefs. In-depth interviews (n = 20) were conducted with US-born, English-speaking Latinas aged 18–25 years in south Florida. Seventeen participants did not intend to get pregnant, while the remaining participants (n = 3) reported that their intentions kept changing. Participants’ beliefs regarding their unintended pregnancy were influenced by social and economic hardship and cultural factors such as fatalism and familismo. Ideas and the meaning of pregnancy differed based on the woman’s pregnancy resolution decision. Many women felt the term ‘unintended pregnancy’ placed blame on women and was stigmatising. When discussing pregnancy planning, most participants felt that women should not plan their pregnancies and doing so was going against fate. Findings suggest that salient influences such as culture and the social determinants related to unintended pregnancy should be incorporated into measurements examining unintended pregnancy
Properties of produced in collisions
No full textWe study the production of the exotic charged charmonium-like state in collisions through the sequential process , . Using the subsample of candidates originating from semi-inclusive weak decays of -flavored hadrons, we measure the invariant mass and natural width to be MeV and MeV, respectively. We search for prompt production of the through the same sequential process. No significant signal is observed, and we set an upper limit of 0.66 at the 95% credibility level on the ratio of prompt production to the production via -hadron decays. The study is based on 10.4 fb of collision data collected by the D0 experiment at the Fermilab Tevatron collider
Deep Underground Neutrino Experiment (DUNE), Far Detector Technical Design Report, Volume I: Introduction to DUNE
No full textThe preponderance of matter over antimatter in the early universe, the dynamics of the supernovae that produced the heavy elements necessary for life, and whether protons eventually decay -- these mysteries at the forefront of particle physics and astrophysics are key to understanding the early evolution of our universe, its current state, and its eventual fate. The Deep Underground Neutrino Experiment (DUNE) is an international world-class experiment dedicated to addressing these questions as it searches for leptonic charge-parity symmetry violation, stands ready to capture supernova neutrino bursts, and seeks to observe nucleon decay as a signature of a grand unified theory underlying the standard model. The DUNE far detector technical design report (TDR) describes the DUNE physics program and the technical designs of the single- and dual-phase DUNE liquid argon TPC far detector modules. This TDR is intended to justify the technical choices for the far detector that flow down from the high-level physics goals through requirements at all levels of the Project. Volume I contains an executive summary that introduces the DUNE science program, the far detector and the strategy for its modular designs, and the organization and management of the Project. The remainder of Volume I provides more detail on the science program that drives the choice of detector technologies and on the technologies themselves. It also introduces the designs for the DUNE near detector and the DUNE computing model, for which DUNE is planning design reports. Volume II of this TDR describes DUNE's physics program in detail. Volume III describes the technical coordination required for the far detector design, construction, installation, and integration, and its organizational structure. Volume IV describes the single-phase far detector technology. A planned Volume V will describe the dual-phase technology
The influence of obesity-related factors in the etiology of renal cell carcinoma-A mendelian randomization study
No full textBackground: Several obesity-related factors have been associated with renal cell carcinoma (RCC), but it is unclear which individual factors directly influence risk. We addressed this question using genetic markers as proxies for putative risk factors and evaluated their relation to RCC risk in a mendelian randomization (MR) framework. This methodology limits bias due to confounding and is not affected by reverse causation. Methods and findings: Genetic markers associated with obesity measures, blood pressure, lipids, type 2 diabetes, insulin, and glucose were initially identified as instrumental variables, and their association with RCC risk was subsequently evaluated in a genome-wide association study (GWAS) of 10,784 RCC patients and 20,406 control participants in a 2-sample MR framework. The effect on RCC risk was estimated by calculating odds ratios (OR) for a standard deviation (SD) increment in each risk factor. The MR analysis indicated that higher body mass index increases the risk of RCC (OR: 1.56, 95% confidence interval [CI] 1.44–1.70), with comparable results for waist-to-hip ratio (OR: 1.63, 95% CI 1.40–1.90) and body fat percentage (OR: 1.66, 95% CI 1.44–1.90). This analysis further indicated that higher fasting insulin (OR: 1.82, 95% CI 1.30–2.55) and diastolic blood pressure (DBP; OR: 1.28, 95% CI 1.11–1.47), but not systolic blood pressure (OR: 0.98, 95% CI 0.84–1.14), increase the risk for RCC. No association with RCC risk was seen for lipids, overall type 2 diabetes, or fasting glucose. Conclusions: This study provides novel evidence for an etiological role of insulin in RCC, as well as confirmatory evidence that obesity and DBP influence RCC risk
Search for Sterile Neutrinos in MINOS and MINOS+ Using a Two-Detector Fit
No full textA search for mixing between active neutrinos and light sterile neutrinos has been performed by looking for muon neutrino disappearance in two detectors at baselines of 1.04 and 735 km, using a combined MINOS and MINOS+ exposure of 16.36 x 10 protons on target. A simultaneous fit to the charged-current muon neutrino and neutral-current neutrino energy spectra in the two detectors yields no evidence for sterile neutrino mixing using a 3 + 1model. The most stringent limit to date is set on the mixing parameter sin for most values of the sterile neutrino mass splitting > 10eV
Less is More: A Cross-Generational Analysis of the Nature and Role of Racial Attitudes in the 21st Century
Get PDFAfter landmark Civil Rights legislation was implemented, scholars provided evidence that the nature and structure of whites’ racial attitudes changed from the Jim Crow era. They devised survey questions to capture newer, more acceptable forms of racial animus. One scale that came out of this effort and that receives the most empirical attention today is the racial resentment scale. Given the vast changes the American racial landscape has undergone since that scale was originally developed, we question whether this set of measures is related to racial attitudes in the same way across generational cohorts. We show two key findings: younger whites are not bringing about any meaningful change in the aggregate levels of racial resentment. Second, and more importantly, we show that while younger whites appear to have lower levels of racial resentment, these survey items are more strongly related to old-fashioned antiblack affect among younger whites. Thus, when it comes to millennials’ racial attitudes, “less is more.