Joint United States-Brazil Billfish Research in the Western South Atlantic

A joint research project between Brazilian and U.S. scientists was initiated in 2004 to investigate the interaction of istiophorid billfishes with pelagic longline fisheries in the western equatorial South Atlantic Ocean. This project incorporates two general themes (1) an investigation into several aspects of pelagic longline operations by comparing catch results between circle and “J” style hooks, time-of-capture with hook time recorders, and by direct monitoring of pelagic longline gear behavior, and (2) an additional evaluation of billfish trophic ecology using a combination of satellite tag technology and traditional analyses (e.g., gut contents and ageing). Data obtained from this research will provide additional data for the evaluation of habitat-based stock assessment modeling efforts for billfish and other pelagic fish species

Construction and Performance of Highway Soil Subgrades Modified with Atmospheric Fluidized Bed Combustion Residue and Multicone Kiln Dust

In an effort to increase the utilization of by-product materials in highway construction projects, the Kentucky Transportation Cabinet authorized the experimental use of reside from an atmospheric fluidized bed combustion (AFBC) process and multicone kiln dust (MKD), a by-product resulting from the production of lime, as subgrade soil modifiers. This report presents information relative to preconstruction and post-construction laboratory evaluations, construction procedures, construction monitoring activities, and performance evaluations of a highway subgrade solid modified using AFBC spent lime, MKD, Type IP cement, and hydrated lime. An untreated section served as a control section for the project located on Kentucky Route 11 in Lee and Wolfe Counties. The laboratory testing program consisted of determining select engineering properties of the solid in a natural state and in a state altered by the chemical admixtures. Index tests were performed, moisture density relationships were determined, and bearing ratio and swell tests were performed. Based on the laboratory unconfined compression tests and bearing capacity tests, the two waste by-products significantly improved the shear strength and bearing strength of the subgrade soil. Field monitoring activities were comprised of both construction monitoring and post-construction monitoring. Construction procedures were essentially the same for all admixture types and no significant problems were encountered. Satisfactory moisture and density were achieved. Construction activities were documented through moisture content and density compliance tests. In-place bearing capacity tests and Road Rater deflection tests were performed on the untreated subgrade and again after modification. The analyses indicated significant improvement in subgrade strength after admixture modification. Post-construction monitoring included determining in-site bearing capacities, assessing moisture conditions and determining soil classifications of the treated and untreated subgrade layers. Road Rater deflection tests were conducted to assess the structural condition of the pavement structure. Results of the field monitoring program confirmed that each chemically modified subgrade continued to exhibit greater strengths than the untreated subgrade section. However, because of non-uniform mixing, the soil-AFBC subgrade sections exhibited severe differential swelling shortly after construction. The bituminous pavement required milling the eliminate humps on the pavement surface. The pavement was overlaid and apparently the subgrade swelling has ceased. However, due to the expansive nature of the AFBC spent lime, future use as a soil modifier could not be recommended. Results of field monitoring activities indicated that MKD was a suitable solid modifier and future use was recommended

The DEEP2 Galaxy Redshift Survey: Mean Ages and Metallicities of Red Field Galaxies at z ~ 0.9 from Stacked Keck/DEIMOS Spectra

As part of the DEEP2 galaxy redshift survey, we analyze absorption line strengths in stacked Keck/DEIMOS spectra of red field galaxies with weak to no emission lines, at redshifts 0.7 <= z <= 1. Comparison with models of stellar population synthesis shows that red galaxies at z ~ 0.9 have mean luminosity-weighted ages of the order of only 1 Gyr and at least solar metallicities. This result cannot be reconciled with a scenario where all stars evolved passively after forming at very high z. Rather, a significant fraction of stars can be no more than 1 Gyr old, which means that star formation continued to at least z ~ 1.2. Furthermore, a comparison of these distant galaxies with a local SDSS sample, using stellar populations synthesis models, shows that the drop in the equivalent width of Hdelta from z ~ 0.9 to 0.1 is less than predicted by passively evolving models. This admits of two interpretations: either each individual galaxy experiences continuing low-level star formation, or the red-sequence galaxy population from z ~ 0.9 to 0.1 is continually being added to by new galaxies with younger stars.Comment: A few typos were corrected and numbers in Table 1 were revise

Preliminary Results of Circle and J-Style Hook Comparisons in the Brazilian Pelagic Longline Fishery

Preliminary studies in western North Atlantic pelagic longline fisheries indicate that a change in terminal gear from J-style hooks to circle hooks may reduce bycatch mortality. However, such studies have not examined the impact of this change in the equatorial fishery. Catch composition, catch rates, hooking location, and condition at haulback were monitored during 26 sets in the commercial longline fishery operating in the western equatorial South Atlantic where circle (size 18/0, non-offset) and J-style (size 9/0 and 10/0, 10° offset) hooks were deployed in an alternating fashion. Catch rates for yellowfin tuna, swordfish, and a composite “all fishes” category were significantly (P \u3c 0.05) higher for circle hooks. Bigeye tuna, swordfish, sailfish, and yellowfin tuna were hooked significantly more often externally than internally. Yellowfin tuna were over eight times more likely to be hooked in the mouth with circle hooks than with J-style hooks. Bigeye tuna and sailfish showed significantly higher rates of survival at haulback with circle hooks. The results suggest that the use of size 18/0 non-offset circle hooks in the equatorial pelagic longline fishery may increase the survival of bycatch species at haulback with minimal detrimental effects on the catches of target species

A higher order perfectly matched layer formulation for finite-difference time-domain seismic wave modeling

We have developed a higher order perfectly matched layer (PML) formulation to improve the absorption performance for finite-difference time-domain seismic modeling. First, we outlined a new unsplit “correction” approach, which allowed for traditional, first-order PMLs to be added directly to existing codes in a straightforward manner. Then, using this framework, we constructed a PML formulation that can be used to construct higher order PMLs of arbitrary order. The greater number of degrees of freedom associated with the higher order PML allow for enhanced flexibility of the PML stretching functions, thus potentially facilitating enhanced absorption performance. We found that the new approach can offer increased elastodynamic absorption, particularly for evanescent waves. We also discovered that the extra degrees of freedom associated with the higher order PML required careful optimization if enhanced absorption was to be achieved. Furthermore, these extra degrees of freedom increased the computational requirements in comparison with first-order schemes. We reached our formulations using one compact equation thus increasing the ease of implementation. Additionally, the formulations are based on a recursive integration approach that reduce PML memory requirements, and do not require special consideration for corner regions. We tested the new formulations to determine their ability to absorb body waves and surface waves. We also tested standard staggered grid stencils and rotated staggered grid stencils

Amniotic fluid volume: Rapid MR-based assessment at 28-32 weeks gestation

Objectives: This work evaluates rapid magnetic resonance projection hydrography (PH) based amniotic fluid volume (AFV) estimates against established routine ultrasound single deepest vertical pocket (SDVP) and amniotic fluid index (AFI) measurements, in utero, at 28-32 weeks gestation. Manual multi-section planimetry (MSP) based measurement of AFV is used as a proxy reference standard. Methods: 35 women with a healthy singleton pregnancy (20-41 years) attending routine antenatal ultrasound were recruited. SDVP and AFI were measured using ultrasound, with same day MRI assessing AFV with PH and MSP. The relationships between the respective techniques were assessed using linear regression analysis and Bland-Altman method comparison statistics. Results: When comparing estimated AFV, a highly significant relationship was observed between PH and the reference standard MSP (R2=0.802, p<0.001). For the US measurements, SDVP measurement related most closely to amniotic fluid volume, (R2=0.470, p<0.001), with AFI demonstrating a weaker relationship (R2=0.208, p=0.007). Conclusion: This study shows that rapid MRI based PH measurement is a better predictor of AFV, relating more closely to our proxy standard than established US techniques. Although larger validation studies across a range of gestational ages are required this approach could form part of MR fetal assessment, particularly where poly or oligohydramnios is suspected.This study was supported by the National Institute of Health Research, Cambridge Biomedical Research Centre. The authors also acknowledge the support of Addenbrooke’s Charitable Trust and thank the participants for their contribution to the study.This is the author accepted manuscript. The final version is available from Springer via http://dx.doi.org/10.1007/s00330-015-4179-

Hydrogeologic Investigations of Pavement Subsidence in the Cumberland Gap Tunnel

Cumberland Gap Tunnel was constructed under Cumberland Gap National Historical Park in 1996 to improve transportation on a segment of U.S. 25E, connecting Kentucky and Tennessee and restoring Cumberland Gap to its historical appearance. The concrete pavement in the tunnel started to subside in 2001. Ground penetrating radar surveys revealed voids in many areas of the limestone roadbed aggregate beneath the pavement. To investigate possible hydrogeologic processes that may have caused favorable conditions for voids to form in the aggregate, we studied geology, groundwater flow, and groundwater chemistry in the tunnel using a variety of methods, including bore drilling, packer test, dye tracing, groundwater- and surface-flow monitoring, water-chemistry modeling, and an aggregate dissolution experiment. The study revealed that the aggregate receives a large volume of groundwater from much of the bedrock invert, but the flow velocity is too slow to transport small particles out of the aggregate. Calcite saturation indices calculated from water-chemistry data suggest that the groundwater was capable of continuously dissolving calcite, the primary mineral in the limestone aggregate. Water samples taken during different flow conditions indicate that groundwater under low-flow conditions. The dissolution experiment showed that all the limestone aggregate placed beneath the roadbed and in contact with groundwater lost mass; the highest mass loss was 3.4 percent during a 178-day period. The experiment also suggested that water with higher calcite-dissolving potential removed limestone mass quicker than water with low calcite-dissolving potential. We recommend that the limestone aggregate be replaced with noncarbonate aggregate, such as granite, to prevent dissolution and future road subsidence

Potential strategies for strengthening surveillance of lymphatic filariasis in American Samoa after mass drug administration: reducing ‘number needed to test’ by targeting older age groups, hotspots, and household members of infected persons

Under the Global Programme to Eliminate Lymphatic Filariasis (LF), American Samoa conducted mass drug administration (MDA) from 2000–2006. Despite passing Transmission Assessment Surveys (TAS) in 2011/2012 and 2015, American Samoa failed TAS-3 in 2016, with antigen (Ag) prevalence of 0.7% (95%CI 0.3–1.8%) in 6–7 year-olds. A 2016 community survey (Ag prevalence 6.2% (95%CI 4.4–8.5%) in age ≥8 years) confirmed resurgence. Using data from the 2016 survey, this study aims to i) investigate antibody prevalence in TAS-3 and the community survey, ii) identify risk factors associated with being seropositive for Ag and anti-filarial antibodies, and iii) compare the efficiency of different sampling strategies for identifying seropositive persons in the post-MDA setting. Antibody prevalence in TAS-3 (n = 1143) were 1.6% for Bm14 (95%CI 0.9–2.9%), 7.9% for Wb123 (95%CI 6.4–9.6%), and 20.2% for Bm33 (95%CI 16.7–24.3%); and in the community survey (n = 2507), 13.9% for Bm14 (95%CI 11.2–17.2%), 27.9% for Wb123 (95%CI 24.6–31.4%), and 47.3% for Bm33 (95%CI 42.1–52.6%). Multivariable logistic regression was used to identify risk factors for being seropositive for Ag and antibodies. Higher Ag prevalence was found in males (adjusted odds ratio [aOR] 3.01), age ≥18 years (aOR 2.18), residents of Fagali’i (aOR 15.81), and outdoor workers (aOR 2.61). Ag prevalence was 20.7% (95%CI 9.7–53.5%) in households of Ag-positive children identified in TAS-3. We used NNTestav (average number needed to test to identify one positive) to compare the efficiency of the following strategies for identifying persons who were seropositive for Ag and each antibody: i) TAS of 6–7 year-old children, ii) population representative surveys of older age groups, and iii) targeted surveillance of subpopulations at higher risk of being seropositive (older ages, householders of Ag-positive TAS children, and known hotspots). For Ag, NNTestav ranged from 142.5 for TAS, to <5 for households of index children. NNTestav was lower in older ages, and highest for Ag, followed by Bm14, Wb123 and Bm33 antibodies. We propose a multi-stage surveillance strategy, starting with population-representative sampling (e.g. TAS or population representative survey of older ages), followed by strategies that target subpopulations and/or locations with low NNTestav. This approach could potentially improve the efficiency of identifying remaining infected persons and residual hotspots. Surveillance programs should also explore the utility of antibodies as indicators of transmission

Scabies prevalence after ivermectin-based mass drug administration for lymphatic filariasis, Samoa 2018–2019

Background: Scabies is a common skin infestation caused by the Sarcoptes scabei mite. Ivermectin, one of three drugs used in mass drug administration (MDA) for lymphatic filariasis, is also effec-tive for treating scabies. Ivermectin-based MDA was first conducted in Samoa in August 2018, with ivermectin being offered to those aged ≥5 years. Here, we report scabies prevalence in Samoa after MDA. Methods: We conducted household surveys 1.5–3.5 months (Survey 1) and 6–8 months (Survey 2) after the 2018 MDA in 35 primary sampling units. We conducted clinical examination for sca-bies-like rash and used International Alliance for the Control of Scabies classification crite-ria. We estimated scabies prevalence by age, gender and region. Multivariable logistic regression was used to assess factors associated with prevalence. Results: We surveyed 2868 people (499 households) and 2796 people (544 households) aged 0–75 years in Surveys 1 and 2, respectively. Scabies prevalence increased from 2.4% (95% CI 2.1–2.7%) to 4.4% (95% CI 4.0–4.9%) between surveys. Scabies was associated with younger age (0–4 years: aOR 3.5 [2.9–4.2]; 5–15 years: aOR 1.6 [1.4–1.8] compared to ≥16 years), female gender (aOR 1.2 [95% CI 1.1–1.4]; region (aOR range from 1.4 [1.1– 1.7] to 2.5 [2.1–3.1] between regions), large households (aOR 2.6 [2.0–3.4] households ≥13), and not taking MDA in 2018 (aOR 1.3 [95% CI 1.1–1.6]). Conclusions: We found moderate prevalence of scabies in two population-representative surveys conducted within 8 months of the 2018 MDA for lymphatic filariasis. Prevalence appeared to increase between the surveys, and ongoing surveillance is recommended, particularly in young children

"On the Spot": travelling artists and Abolitionism, 1770-1830

Until recently the visual culture of Atlantic slavery has rarely been critically scrutinised. Yet in the first decades of the nineteenth century slavery was frequently represented by European travelling artists, often in the most graphic, sometimes voyeuristic, detail. This paper examines the work of several itinerant artists, in particular Augustus Earle (1793-1838) and Agostino Brunias (1730–1796), whose very mobility along the edges of empire was part of a much larger circulatory system of exchange (people, goods and ideas) and diplomacy that characterised Europe’s Age of Expansion. It focuses on the role of the travelling artist, and visual culture more generally, in the development of British abolitionism between 1770 and 1830. It discusses the broad circulation of slave imagery within European culture and argues for greater recognition of the role of such imagery in the abolitionist debates that divided Britain. Furthermore, it suggests that the epistemological authority conferred on the travelling artist—the quintessential eyewitness—was key to the rhetorical power of his (rarely her) images. Artists such as Earle viewed the New World as a boundless source of fresh material that could potentially propel them to fame and fortune. Johann Moritz Rugendas (1802-1858), on the other hand, was conscious of contributing to a global scientific mission, a Humboldtian imperative that by the 1820s propelled him and others to travel beyond the traditional itinerary of the Grand Tour. Some artists were implicated in the very fabric of slavery itself, particularly those in the British West Indies such as William Clark (working 1820s) and Richard Bridgens (1785-1846); others, particularly those in Brazil, expressed strong abolitionist sentiments. Fuelled by evangelical zeal to record all aspects of the New World, these artists recognised the importance of representing the harsh realities of slave life. Unlike those in the metropole who depicted slavery (most often in caustic satirical drawings), many travelling artists believed strongly in the evidential value of their images, a value attributed to their global mobility. The paper examines the varied and complex means by which visual culture played a significant and often overlooked role in the political struggles that beset the period