Vortex dynamics

Vortex flows of interest to aerodynamicists cover a wide range of scales from a fraction of an inch in boundary layer flows to many feet in wake flows. In many applications these flows are poorly understood and, due to their complexity, present a challenge both analytically and experimentally. Four topics representing the spectrum of experimental and analytical vortex research are presented

Audit of antenatal clinic for high-risk obstetric patients; activity and outcomes

A specialised clinic for the antenatal care of high-risk patients was established in Cork in January 2004. It is led by 2 specialists in materno-fetal medicine and provides care for patients from a large catchment area. Small clinic numbers, specialised midwives, ready access to medical experts and fetal assessment facilities, facilitate an efficient use of resources. We report on the experience and outcomes of this clinic after the first year in operation. A database was set up to store relevant information on patients who attended the clinic in 2004. 143 patients attended. Risk categories included maternal medical disease (62%); multiple pregnancy (11%); previous poor obstetric history (10%); fetal anomaly (8%). Average gestation; 35.9 weeks, average birth weight; 2598g. Caesarean section rate; 41%. Perinatal mortality rate 67 per 1000 (uncorrected); and 20% neonates required NICU care. This approach to highrisk obstetric care resulted in favourable outcomes. The management strategy applied in Cork may be a suitable prototype for comparable areas throughout Ireland

Along-margin variations in breakup volcanism at the Eastern North American Margin

Author Posting. © American Geophysical Union, 2020. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Journal of Geophysical Research: Solid Earth 125(12),(2020): e2020JB020040, https://doi.org/10.1029/2020JB020040.We model the magnetic signature of rift‐related volcanism to understand the distribution and volume of magmatic activity that occurred during the breakup of Pangaea and early Atlantic opening at the Eastern North American Margin (ENAM). Along‐strike variations in the amplitude and character of the prominent East Coast Magnetic Anomaly (ECMA) suggest that the emplacement of the volcanic layers producing this anomaly similarly varied along the margin. We use three‐dimensional magnetic forward modeling constrained by seismic interpretations to identify along‐margin variations in volcanic thickness and width that can explain the observed amplitude and character of the ECMA. Our model results suggest that the ECMA is produced by a combination of both first‐order (~600–1,000 km) and second‐order (~50–100 km) magmatic segmentation. The first‐order magmatic segmentation could have resulted from preexisting variations in crustal thickness and rheology developed during the tectonic amalgamation of Pangaea. The second‐order magmatic segmentation developed during continental breakup and likely influenced the segmentation and transform fault spacing of the initial, and modern, Mid‐Atlantic Ridge. These variations in magmatism show how extension and thermal weakening was distributed at the ENAM during continental breakup and how this breakup magmatism was related to both previous and subsequent Wilson cycle stages.Thanks to Anne Bécel, Dan Lizarralde, Collin Brandl, Brandon Shuck, and Mark Everett for beneficial discussion and assistance in compiling the archived data used in this study. We thank Debbie Hutchinson (USGS Woods Hole Coastal and Marine Science Center) for passing along her vast breadth of knowledge on the ENAM through numerous constructive suggestions to greatly strengthen our manuscript. We greatly appreciate the insightful comments from two reviewers, the Associate Editor, and the Editor that significantly improved the manuscript. Thanks to Maurice Tivey for providing codes that aided our magnetic modeling efforts. Project completed as part of J.A.G.'s Ph.D. dissertation at Texas A&M University.2021-05-1

Representative bureaucracy: does female police leadership affect gender-based violence arrests?

Representative bureaucracy theory postulates that passive representation leads to active representation of minority groups. This article investigates the passive representation of female police officers at leadership levels and the active representation of women vis-a-vis gender-based violence arrest rates in the UK. Much of the extant research on representative bureaucracy is located at street level, with evidence showing that discretionary power of minority bureaucrats can lead to active representation. This article is focused on leadership levels of a public bureaucracy. The empirical research is based upon a panel dataset of female police officers as an independent variable and gender-based violence arrest rates as a dependent variable. The analysis reveals that there is little evidence of active representation of women by female police leadership

Refining the formation and early evolution of the Eastern North American Margin : new insights from multiscale magnetic anomaly analyses

Author Posting. © American Geophysical Union, 2017. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Journal of Geophysical Research: Solid Earth 122 (2017): 8724–8748, doi:10.1002/2017JB014308.To investigate the oceanic lithosphere formation and early seafloor spreading history of the North Atlantic Ocean, we examine multiscale magnetic anomaly data from the Jurassic/Early Cretaceous age Eastern North American Margin (ENAM) between 31 and 40°N. We integrate newly acquired sea surface magnetic anomaly and seismic reflection data with publicly available aeromagnetic and composite magnetic anomaly grids, satellite-derived gravity anomaly, and satellite-derived and shipboard bathymetry data. We evaluate these data sets to (1) refine magnetic anomaly correlations throughout the ENAM and assign updated ages and chron numbers to M0–M25 and eight pre-M25 anomalies; (2) identify five correlatable magnetic anomalies between the East Coast Magnetic Anomaly (ECMA) and Blake Spur Magnetic Anomaly (BSMA), which may document the earliest Atlantic seafloor spreading or synrift magmatism; (3) suggest preexisting margin structure and rifting segmentation may have influenced the seafloor spreading regimes in the Atlantic Jurassic Quiet Zone (JQZ); (4) suggest that, if the BSMA source is oceanic crust, the BSMA may be M series magnetic anomaly M42 (~168.5 Ma); (5) examine the along and across margin variation in seafloor spreading rates and spreading center orientations from the BSMA to M25, suggesting asymmetric crustal accretion accommodated the straightening of the ridge from the bend in the ECMA to the more linear M25; and (6) observe anomalously high-amplitude magnetic anomalies near the Hudson Fan, which may be related to a short-lived propagating rift segment that could have helped accommodate the crustal alignment during the early Atlantic opening.J. A. G. and M. T. thank the Department of Geology and Geophysics at Texas A&M University for their support of J. A. G.’s PhD program. M. T. and M. R. K. thank the Department of Earth and Environmental Sciences at Michigan State University for their support during M. R. K.’s MS thesis project, included in this study.2018-05-1

Air Traffic Management Technology Demonstration-1 Concept of Operations (ATD-1 ConOps)

The operational goal of the ATD-1 ConOps is to enable aircraft, using their onboard FMS capabilities, to fly Optimized Profile Descents (OPDs) from cruise to the runway threshold at a high-density airport, at a high throughput rate, using primarily speed control to maintain in-trail separation and the arrival schedule. The three technologies in the ATD-1 ConOps achieve this by calculating a precise arrival schedule, using controller decision support tools to provide terminal controllers with speeds for aircraft to fly to meet times at a particular meter points, and onboard software providing flight crews with speeds for the aircraft to fly to achieve a particular spacing behind preceding aircraft

Direct Picosecond Measurement of Photoinduced Cooper Pair Breaking in Lead

We report on a direct kinetic measurement of Cooper-pair breaking in superconducting lead. A 100-fs pulse of visible light was used to excite a thin-film lead sample, while the Cooper-pair density was optically probed using an ultrashort pulse of broadband far-infrared radiation. Subsequent to the absorption of the visible light, a rapid (ps) change in the far-infrared optical transmission was observed, corresponding to the breaking of Cooper pairs and the collapse of the superconducting gap