Seafloor seismicity, Antarctic ice-sounds, cetacean vocalizations and long-term ambient sound in the Indian Ocean basin

International audienceThis paper presents the results from the Deflo-hydroacoustic experiment in the Southern Indian Ocean using three autonomous underwater hydrophones, complemented by two permanent hydroacoustic stations. The array monitored for 14 months, from November 2006 to December 2007, a 3000 x 3000 km wide area, encompassing large segments of the three Indian spreading ridges that meet at the Indian Triple Junction. A catalogue of 11 105 acoustic events is derived from the recorded data, of which 55 per cent are located from three hydrophones, 38 per cent from 4, 6 per cent from five and less than 1 per cent by six hydrophones. From a comparison with land-based seismic catalogues, the smallest detected earthquakes are m(b) 2.6 in size, the range of recorded magnitudes is about twice that of land-based networks and the number of detected events is 5-16 times larger. Seismicity patterns vary between the three spreading ridges, with activity mainly focused on transform faults along the fast spreading Southeast Indian Ridge and more evenly distributed along spreading segments and transforms on the slow spreading Central and ultra-slow spreading Southwest Indian ridges; the Central Indian Ridge is the most active of the three with an average of 1.9 events/100 km/month. Along the Sunda Trench, acoustic events mostly radiate from the inner wall of the trench and show a 200-km-long seismic gap between 2 degrees S and the Equator. The array also detected more than 3600 cryogenic events, with different seasonal trends observed for events from the Antarctic margin, compared to those from drifting icebergs at lower (up to 50 degrees S) latitudes. Vocalizations of five species and subspecies of large baleen whales were also observed and exhibit clear seasonal variability. On the three autonomous hydrophones, whale vocalizations dominate sound levels in the 20-30 and 100 Hz frequency bands, whereas earthquakes and ice tremor are a dominant source of ambient sound at frequencies < 20 Hz

Measuring Segmented Primary Mirror WFE in the Presence of Vibration and Thermal Drift on the Light-Weighted JWST

The light-weighted design of the Optical Telescope Element (OTE) of the James Webb Telescope (JWST) leads to additional sensitivity to vibration from the ground - an important consideration to the measurement uncertainty of the wavefront error (WFE) in the primary mirror. Furthermore, segmentation of the primary mirror leads to rigid-body movements of segment areas in the WFE. The ground vibrations are minimized with modifications to the test facility, and by the architecture of the equipment supporting the load. Additional special test equipment (including strategically placed isolators, tunable mass dampers, and cryogenic magnetic dampers) mitigates the vibration and the response sensitivity before reaching the telescope. A multi-wavelength interferometer is designed and operated to accommodate the predicted residual vibration. Thermal drift also adds to the measurement variation. Test results of test equipment components, measurement theory, and finite element analysis combine to predict the test uncertainty in the future measurement of the primary mirror. The vibration input to the finite element model comes from accelerometer measurements of the facility with the environmental control pumps operating. One of the isolators have been built and tested to validate the dynamic performance. A preliminary model of the load support equipment and the OTE with the Integrated Science Instrument Module (ISIM) is complete. The performance of the add-on dampers have been established in previous applications. And operation of the multi-wavelength interferometer was demonstrated on a scaled hardware version of the JWST in an environment with vibration and thermal drift

Modeling of Large Pharmacokinetic Data Using Nonlinear Mixed-Effects: A Paradigm Shift in Veterinary Pharmacology. A Case Study With Robenacoxib in Cats

The objective of this study was to model the pharmacokinetics (PKs) of robenacoxib in cats using a nonlinear mixed‐effects (NLME) approach, leveraging all available information collected from cats receiving robenacoxib s.c. and/or i.v.: 47 densely sampled laboratory cats and 36 clinical cats sparsely sampled preoperatively. Data from both routes were modeled sequentially using Monolix 4.3.2. Influence of parameter correlations and available covariates (age, gender, bodyweight, and anesthesia) on population parameter estimates were evaluated by using multiple samples from the posterior distribution of the random effects. A bicompartmental disposition model with simultaneous zero and first‐order absorption best described robenacoxib PKs in blood. Clearance was 0.502 L/kg/h and the bioavailability was high (78%). The absorption constant point estimate (Ka = 0.68 h−1) was lower than beta (median, 1.08 h−1), unveiling flip‐flop kinetics. No dosing adjustment based on available covariates information is advocated. This modeling work constitutes the first application of NLME in a large feline population

The Italians: Communicating in a Discourse Community

For a discourse community assignment, I decided that I would write about something that I am proud to be called: an Italian. Being only part Italian, I grew up on many different aspects and traditions that I still use in my lifetime, whether it would be food, art, or how I celebrate the holidays. It is a big part of my culture that I am proud to write about

Psychosocial Work Quality, Work-Family Conflict, and Psychological Distress: A Comparison of Single and Partnered Mothers

Research suggests that single mothers experience poorer mental and physical health than their partnered counterparts. This health differential has been attributed, in large part, to the chronic economic and social stressors to which many single mothers are exposed. Less research, however, has focused on the well-being of single mothers who are employed, despite their growing presence in the Canadian labour force. Using data from a telephone survey of employed parents in a mid-sized Western Canadian city conducted in 2005, the aim of this study was to: (1) compare the mental health of employed, single mothers relative to partnered mothers; and (2) explore the potential role of work-family conflict and psychosocial job characteristics as explanations for any observed differences in psychological distress. Analyses were restricted to 674 employed mothers (438 partnered and 236 single), who were 25-50 years old, with at least one child in the household under the age of 20 years. Bivariate analysis indicated that compared to partnered mothers, employed single mothers reported significantly higher levels of psychological distress, work-to-family conflict and family-to-work conflict. Single mothers were also more likely to be employed in a high-strain psychosocial work environment (i.e., high demand and low control). Multiple linear regression revealed that after adjusting for key sociodemographic characteristics, psychosocial work quality and work-family conflict, single parenthood was no longer statistically significantly associated with psychological distress. These findings suggest that being a single mother in and of itself need not result in poorer mental health, but greater attention needs to be paid to the economic and psychosocial work environment of single mothers, including policies to facilitate work-family balance

Spatiotemporal distribution of the seismicity along the Mid-Atlantic Ridge north of the Azores from hydroacoustic data: Insights into seismogenic processes in a ridge-hot spot context

The seismicity of the North Atlantic was monitored from May 2002 to September 2003 by the 'SIRENA array' of autonomous hydrophones. The hydroacoustic signals provide a unique data set documenting numerous low-magnitude earthquakes along the section of the Mid-Atlantic Ridge (MAR) located in a ridge-hot spot interaction context. During the experiment, 1696 events were detected along the MAR axis between 40 degrees N and 51 degrees N, with a magnitude of completeness level of m(b) approximate to 2.4. Inside the array, location errors are in the order of 2 km, and errors in the origin time are less than 1 s. From this catalog, 15 clusters were detected. The distribution of source level (SL) versus time within each cluster is used to discriminate clusters occurring in a tectonic context from those attributed to non-tectonic (i.e. volcanic or hydrothermal) processes. The location of tectonic and non-tectonic sequences correlates well with regions with positive and negative Mantle Bouguer Anomalies (MBAs), indicating the presence of thinner/colder and thicker/warmer crust respectively. At the scale of the entire array, both the complete and declustered catalogs derived from the hydroacoustic signals show an increase of the seismicity rate from the Azores up to 43 degrees 30'N suggesting a diminishing influence of the Azores hot spot on the ridge-axis temperature, and well correlated with a similar increase in the along-axis MBAs. The comparison of the MAR seismicity with the Residual MBA (RMBA) at different scales leads us to think that the low-magnitude seismicity rates are directly related to along-axis variations in lithosphere rheology and temperatures.info:eu-repo/semantics/publishedVersio

Finding Oneself Through Her, Through Him: An Exploration of Rosalind’s Gender Fluidity in As You Like It

This senior project involved performing the role of Rosalind in an original adaptation of William Shakespeare’s As You Like It, performed outdoors with a gender-diverse cast, with the intent to convey queer gender struggle and express the theme of love surpassing all barriers. This work was supported by research into previous queer interpretations of the play and its impact on our understanding of Shakespeare, analyzing the portrayal of Rosalind in three contemporary productions: Cheek by Jowl (1991), Baltimore Center Stage (2016), and La Jolla Playhouse (2022).Purchase College SUNYTheatre and PerformanceBachelor of ArtsSchildcrout, Jordan R

Use of measurement theory for operationalization and quantification of psychological constructs in systems dynamics modelling

The analytical tools available to social scientists have traditionally been adapted from tools originally designed for analysis of natural science phenomena. This article discusses the applicability of systems dynamics - a qualitative based modelling approach, as a possible analysis and simulation tool that bridges the gap between social and natural sciences. After a brief overview of the systems dynamics modelling methodology, the advantages as well as limiting factors of systems dynamics to the potential applications in the field of social sciences and human interactions are discussed. The issues arise with regards to operationalization and quantification of latent constructs at the simulation building stage of the systems dynamics methodology and measurement theory is proposed as a ready and waiting solution to the problem of dynamic model calibration, with a view of improving simulation model reliability and validity and encouraging the development of standardised, modular system dynamics models that can be used in social science research