Coherent backscattering of ultrasound without a source

Coherent backscattering is due to constructive interferences of reciprocal paths and leads to an enhancement of the intensity of a multiply scattered field near its source. To observe this enhancement an array of receivers is conventionally placed close to the source. Our approach here is different. In a first experiment, we recover the coherent backscattering effect (CBE) within an array of sources and a distant receiver using time correlation of diffuse fields. The enhancement cone has an excellent spatial resolution. The dynamics of the enhancement factor is studied in a second experiment using correlation of thermal phonons at the same ultrasonic frequencies, without any active source

The Impact of Obesity on Employment Participation and Earnings among Working-Age Women in Canada: Evidence from the NPHS Longitudinal Data

Background: The direct medical care costs attributable to obesity are well-known, but little is known about the indirect costs of obesity. In particular, less is known about the impact of obesity on employment participation and earnings, especially among women in Canada. Objectives: The objectives of this study are to examine the association between obesity and employment participation and earnings, if employed, among Canadian women. Methods: Data were taken from the last six cycles of the National Population Health Survey from 2000/01-2010/11 longitudinal cohort data from women aged 18-53 years. The association between obesity and labour market participation was analyzed using pooled, random-effects and fixed-effects regression modeling techniques. The association between obesity and earnings (wage and income) was analyzed using pooled, truncated random-effects and truncated fixed-effects regression models. Results: Wage rate and annual income were found to be negatively associated with obesity. The negative association persisted between obesity and annual income even after accounting for individual-specific effects in the regression analysis. The effect of obesity on employment participation was not significant once health and lifestyle variables were controlled for. Conclusions: This longitudinal analysis of Canadian women demonstrated that obesity has a negative effect on earnings and this effect remains statistically significant even after controlling for individual-specific heterogeneity

The relationship between body mass index, binge eating disorder and suicidality

Abstract Background While restrictive and compensatory eating disorders (e.g. anorexia and bulimia) are associated with elevated risk of suicide, less is known about binge eating disorder (BED). There is suggestive evidence of a U-shaped relationship between body mass index (BMI) and completed suicide, but fewer studies on suicidal ideation or attempts. This study examined the association between BED, BMI, and suicidality, and assessed whether these relationships varied by gender. Methods Data come from the Collaborative Psychiatric Epidemiologic Surveys (N = 14,497). Binge episodes and BED were assessed using the Composite International Diagnostic Inventory (CIDI). BMI was calculated from self-reported height and weight. Suicidal ideation/attempts were assessed using the CIDI. Weighted logistic regression was used to assess the association between binging/BED, BMI and suicidality. Interaction terms were used to assess whether the relationship between BMI and suicidality was moderated by binging/BED, and whether the relationships between binging/BED and BMI differed by gender. Results One-third of adults with BED had a history of suicidality, compared to 19% of those without. Both binging (OR: 1.95, 95% CI: 1.50–2.53) and BED (OR: 2.01, 95% CI: 1.41–2.86) were associated with suicidality in fully-adjusted models. BMI was associated with suicidality in a curvilinear manner, and this relationship was exacerbated by binging/BED (ORBinge eating x BMI: 1.04, 95% CI: 1.01–1.09, p < 0.05). The relationship between BMI and suicidality did not differ by gender (ORgender x BMI: 1.00, p < 0.770). However, the relationship between binge eating and suicidality was stronger for women relative to men (ORgender X binge: 1.87, p < 0.012). Conclusions Binge eating, even below the threshold for BED, is associated with suicidality. BMI is associated with suicidality in a curvilinear manner, and the BMI-suicidality relationship is potentiated by binge eating/BED. Findings support the thoughtful integration of psychiatric care into weight loss programs for adults with a history of binging behavior.https://deepblue.lib.umich.edu/bitstream/2027.42/144500/1/12888_2018_Article_1766.pd

On the precision of noise correlation interferometry.

International audienceLong duration noisy-looking waveforms such as those obtained in randomly multiple scattering and reverberant media are complex; they resist direct interpretation. Nevertheless, such waveforms are sensitive to small changes in the source of the waves or in the medium in which they propagate. Monitoring such waveforms, whether obtained directly or obtained indirectly by noise correlation, is emerging as a technique for detecting changes in media. Interpretation of changes is in principle problematic; it is not always clear whether a change is due to sources or to the medium. Of particular interest is the detection of small changes in propagation speeds. An expression is derived here for the apparent, but illusory, waveform dilation due to a change of source. The expression permits changes in waveforms due to changes in wave speed to be distinguished with high precision from changes due to other reasons. The theory is successfully compared with analysis of a laboratory ultrasonic data set and a seismic data set from Parkfield California

Tumors in Space: Preparation for Spaceflight

Tumors in Space is a cutting-edge cancer research experiment at the intersection of stem-cell biology and space technology selected by the United Nations Office for Outer Space Affairs and the China Manned Space Agency for a 31-day space mission on board the China Space Station. Anchored in Norway, Tumors in Space includes an international team of exceptional scientists at several European partner organizations including the University of Oslo and the Norwegian University of Science and Technology in Norway, the International Space University in France, the Belgian Nuclear Research Center in Belgium, and Vrije University Amsterdam as well as the Hubrecht Institute in The Netherlands. This chapter first presents our two novel hypotheses including the current state of scientific evidence upon which our hypotheses are based. Following, the seven main steps of our spaceflight preparation are discussed within the context of our 2025 launch date from China. Finally, some thoughts on impact, including support for the United Nation’s Sustainable Development Goals and commitment to science communication in the public domain, are given. Tumors is Space is under a programme of, and funded by the European Space Agency with the support of the Norwegian Space Agency

On the reduction of the CSP dichotomy conjecture to digraphs

It is well known that the constraint satisfaction problem over general relational structures can be reduced in polynomial time to digraphs. We present a simple variant of such a reduction and use it to show that the algebraic dichotomy conjecture is equivalent to its restriction to digraphs and that the polynomial reduction can be made in logspace. We also show that our reduction preserves the bounded width property, i.e., solvability by local consistency methods. We discuss further algorithmic properties that are preserved and related open problems.Comment: 34 pages. Article is to appear in CP2013. This version includes two appendices with proofs of claims omitted from the main articl

Examination of Urinary Pesticide Concentrations, Protective Behaviors, and Risk Perceptions Among Latino and Latina Farmworkers in Southwestern Idaho

Introduction: Studies have documented high levels of pesticide exposure among men farmworkers; however, few have examined exposures or the experiences of women farmworkers. Data gaps also exist regarding farmworkers’ perceived risk and control related to pesticides, information that is critical to develop protective interventions. Objective: We aimed to compare urinary pesticide biomarker concentrations between Latino and Latina farmworkers and examine associations with occupational characteristics, risk perceptions, perceived control, and protective behaviors. Methods: We enrolled a convenience sample of 62 farmworkers (30 men and 32 women) during the pesticide spray season from April–July 2022 in southwestern Idaho. Participants were asked to complete two visits within a seven-day period; at each visit, we collected a urine sample and administered a questionnaire assessing demographic and occupational information. Urine samples were composited and analyzed for 17 biomarkers of herbicides and of organophosphate (OP) and pyrethroid insecticides. Results: Ten pesticide biomarkers (TCPy, MDA, PNP, 3-PBA, 4-F-3-PBA, cis- and trans-DCCA, 2,4-D, Glyphosate, AMPA) were detected in \u3e80% of samples. Men and women had similar urinary biomarker concentrations (p = 0.19–0.94); however, women worked significantly fewer hours than men (p = 0.01), wore similar or greater levels of Personal Protective Equipment (PPE), and were slightly more likely to report having experienced an Acute Pesticide Poisoning (26% of women vs. 14% of men; p = 0.25). We observed inconsistencies in risk perceptions, perceived control, and protective behaviors among men. Discussion: Our study is one the first to examine pesticide exposure and risk perceptions among a cohort of farmworkers balanced on gender. Taken with previous findings, our results suggest that factors such as job tasks, biological susceptibility, or access to trainings and protective equipment might uniquely impact women farmworkers’ exposure and/or vulnerability to pesticides. Women represent an increasing proportion of the agricultural workforce, and larger studies are needed to disentangle these findings