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Copyright of Hydrogeology Journal is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

High‐resolution shallow sub‐bottom seismic survey data obtained for the Dudgeon windfarm site located 50 km offshore of the north Norfolk coast in the southern North Sea have revealed that the chalk bedrock in this area is overlain by sediments deposited during the Elsterian and Weichselian glacial periods. A buried N–S‐trending subglacial drainage channel (tunnel valley) filled with Swarte Bank Formation (MIS 12) sediments indicates that the maximum extent of the Elsterian ice‐sheet margin occurred further to the south. Detailed cross‐sections constructed from the seismic data reveal the presence of buried thrust‐block moraine system composed of deformed (folded and thrusted) Swarte Bank Formation sediments, lying beneath a younger sequence of sediments dominated by the glacigenic Bolders Bank Formation (MIS 2). The geometry of the folds and sense of offset on the thrusts, coupled with the morphology of the ridge‐like landforms within this buried moraine system, are consistent with deformation having occurred in response to ice‐push from the N/NE. The chalk bedrock that underlies the glaciotectonized sequence is thought to have provided an antecedent control on the location and preservation of this moraine system. A three‐phase model is proposed to explain the evolution of this thrust‐moraine complex that formed at the oscillating ice margin during the overall active retreat of the Elsterian ice sheet. [ABSTRACT FROM AUTHOR]

The southern North Sea is a particularly important area for understanding the behaviour of the British-Irish Ice Sheet (BIIS) during the last glacial cycle. It preserves a record of the maximum extent of the eastern sector of the BIIS as well as evidence for multiple different ice flow phases and the dynamic re-organisation of the BIIS. This paper explores the origin and age of the Dogger Bank (DB); re-assesses the extent and age of the glaciogenic deposits across the shallow areas of the North Sea adjacent to the Dogger Bank and; re-examines the dynamic behaviour of the BIIS in the southern North Sea between 30 – 19 ka.The DB is composed predominantly by glaciolacustrine sediment deposited between 31.6 – 25.8 ka. Following its formation the western end of the Dogger lake was overridden with initial ice override and retreat northwards back across the Dogger lake complete by 23.1 ka. This resulted in widespread compressive glaciotectonism of the lake sediments and the formation of thrust moraine complexes. Along the northern edge of the DB, moraines are on-lapped by later phase glaciolacustrine and marine sediments but do not show evidence of subsequent ice override.The seafloor to the west/southwest of the DB records several later phases of ice advance and retreat as the North Sea Lobe (NSL) flowed between the DB and the Yorkshire/Lincolnshire coast. New OSL ages limit the arrival of the BIIS on the Norfolk coast to 22.8 – 21.5 ka, after which multiple till sheets and moraines on the seafloor mark northwards retreat of the NSL. This pattern of behaviour is broadly synchronous with the terrestrial sedimentary record along the Yorkshire coast which relates to post Dimlington Stadial NSL oscillation and retreat (~ 21.5 ka)With respect to forcing mechanisms it is likely that during the early phases of the LGM (~30-23ka) the interaction between the southern margin of the BIIS and the Dogger Lake was critical in influencing flow instability and rapid ice advance and retreat. However, during the latter part of the LGM (22 - 21 ka) late-phase ice advance in the southern North Sea became restricted to the western side of the DB which was a substantial topographic feature by this time. This topographic confinement, in addition to decoupling of the BIIS and the Fennoscandian Ice Sheet further north, enabled ice to reach the Norfolk coast, subsequently overprinting the seabed with late-phase tills of the Bolders Bank Fm. [ABSTRACT FROM AUTHOR]

Information about the topics discussed at the 2010 Technical Association of the Pulp and Paper Industry (TAPPI) Pulping, Engineering, Environmental, Recycling and Sustainability (PEERS) Conference and the 9th Research Forum on Recycling held on October 17-21 in Norfolk, Virginia is presented. The topics included sustainability efforts by the companies and how they impact business. Moreover, there was discussion on hemicellulose extraction and pulp mill repurposing for ethanol production.

Purpose: Cone beam computed tomography (CBCT) imaging has been implemented on the Leksell Gamma Knife® Icon™ for assessing patient positioning in mask‐based Gamma Knife radiosurgery. The purpose of this study was to evaluate the performance of the CBCT‐based patient positioning system as a tool for frameless Gamma Knife radiosurgery. Methods: Daily quality assurance (QA) CBCT precision test results from a 12‐month period were analyzed for the geometric accuracy and the stability of the imager. The performance of the image acquisition module and the image registration algorithm was evaluated using an anthropomorphic head phantom (CIRS Inc., Norfolk, VA) and a XYZR axis manual positioning stage (TOAUTO Inc., Guangdong, China). The head phantom was fixed on a mask adaptor and manually translated in the X, Y, Z directions or rotated around the X, Y, Z axes in the range of ±10 mm or ±10º. A CBCT scan was performed after each manual position setup followed by an image registration to the reference scan. To assess the overall setup uncertainties in fractionated treatment, two cylindrical Presage phantoms (Heuris Inc., Skillman, NJ) of 15 cm diameter and 10 cm height were irradiated with identical prescription dose and shot placement following standard mask‐based treatment workflow according to two different fraction schedules: a single fraction treatment of 7.5 Gy and a 5‐fraction treatment with 1.5 Gy per fraction. Results: The averaged vector deviations of the four marks from their preset values are 0.087, 0.085, 0.095, and 0.079 mm from the 212 daily QA tests. The averaged displacements in the X, Y, Z coordinates and the pitch, yaw, roll angles from the image registration tests are 0.23, 0.27, 0.14, 0.32º, 0.19º, 0.31º from the manual setup. The corresponding maximum differences are 0.41, 0.33, 0.29 mm, 0.45º, 0.31º, and 0.43º, respectively. Compared to the treatment plan using the 2% & 1 mm criteria, the averaged 2D Gamma passing rate is 98.25% for the measured dose distribution from the Presage phantom with 1‐fraction irradiation and 95.12% for the 5‐fraction irradiation. The averaged Gamma passing rates are 99.53% and 98.16% for the 1‐fraction and 5‐fraction irradiations using the 2% & 2 mm criteria. Conclusions: The CBCT imager and the image registration algorithm can reproduce phantom position with <0.5 mm/0.5º uncertainty. A systematic contribution from the interfraction phantom repositioning procedure was observed in the Gamma analysis over the irradiated volumes of two end‐to‐end test phantoms. [ABSTRACT FROM AUTHOR]

Chemosynthetic environments support distinct benthic communities capable of utilizing reduced chemical compounds for nutrition. Hundreds of methane seeps have been documented along the U.S. Atlantic margin (USAM), and detailed investigations at a few seeps have revealed distinct environments containing mussels, microbial mats, authigenic carbonates, and soft sediments. The dominant mussel, Bathymodiolus childressi , contains methanotrophic endosymbionts but is also capable of filter feeding, and stable isotope analysis (SIA) of mussel-shell periostracum suggests that these mussels are mixotrophic, assimilating multiple food resources. However, it is unknown whether mixotrophy is widespread or varies spatially and temporally. We used SIA (δ13C, δ15N, and δ34S) and an isotope mixing model (MixSIAR) to estimate resource contribution to B. childressi and characterize food webs at two seep sites (Baltimore Seep; 400 m and Norfolk Seep; 1500 m depths) along the USAM, and applied a linear mixed-effects model to explore the role of mussel population density and tissue type in influencing SIA variance. After controlling for location and temporal variation, isotopic variability was a function of proportion of live mussels present and tissue type. Isotopic differences were also spatially discrete, possibly reflecting variations in the underlying carbon source at the two sites. Low mussel δ13C values (∼−63‰) are consistent with a dependence on microbial methane. However, MixSIAR results revealed mixotrophy for mussels at both sites, implying a reliance on a mixture of methane and phytoplankton-derived particulate organic material. The mixing model results also reveal population density-driven patterns, suggesting that resource use is a function of live mussel abundance. Mussel isotopes differed by tissue type, with gill having the lowest δ15N values relative to muscle and mantle tissues. Based on mass balance equations, up to 79% of the dissolved inorganic carbon (DIC) of the pore fluids within the anaerobic oxidation of the methane zone is derived from methane and available to fuel upper slope deep-sea communities, such as fishes (Dysommina rugosa and Symphurus nebulosus), echinoderms (Odontaster robustus , Echinus wallisi , and Gracilechinus affinis), and shrimp, (Alvinocaris markensis). The presence of these seeps thereby increases the overall trophic and community diversity of the USAM continental slope. Given the presence of hundreds of seeps within the region, primary production at seeps may serve as an important, yet unquantified, energy source to the USAM deep-sea environment. • First analysis of food webs within recently discovered seeps in the U.S. Atlantic. • First application of MixSIAR to estimate resource contribution to seep mussels. • Mussel tissue isotope variability was influenced by mussel densities and tissue type. • Seep associates relied on a mixture of seep-derived carbon and phytodetritus. • Seep presence increases the trophic and community diversity of the US Atlantic Margin. [ABSTRACT FROM AUTHOR]

The rapidly growing eighteenth-century port city of Norfolk, Virginia, occupied an unusual position. It was the largest city in a colony known for its rural gentry culture and also a formally incorporated borough in an era when urban corporate independence was increasingly unusual in the British Atlantic. This essay explores Norfolk's corporate political identity and argues that it was crucial to the city's position in a planter-dominated society. The charter helped reconcile the city's need for local authority over trade and urban policing with the planter elite's suspicion of commerce by effectively quarantining the port city outside the planters' political world. As tensions rose within the British Empire during the 1760s, however, the borough's corporate authority became a contentious issue, as planters asserted their civic authority to regulate trade. The planter revolutionaries' suspicion of Norfolk's corporate status led to the showdown between the borough and the new revolutionary government and eventually to the destruction of the city in January 1776. These experiences informed the efforts of Virginia's new state government to craft a unique subsidiary status for municipal government in the 1780s. Norfolk's corporate status is therefore crucial to understanding the republican political economic vision of Virginia's planter class. [ABSTRACT FROM AUTHOR]

Copyright of Southeastern Geographer is the property of University of North Carolina Press and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A novel application of web-based virtual laboratories to prepare students for physical experiments is explored in some detail. The pedagogy of supplementing physical laboratory with web-based virtual laboratories is implemented by developing a web-based tool, designated in this work as "eLIVE", an acronym for Engineering Laboratory Instruction in Virtual Environment. Two physical experiments, one each from the thermo-fluids laboratory and the solid mechanics laboratory in the undergraduate mechanical engineering curriculum, are transformed into web-based virtual experiments for application as pre-lab practice sessions. The key question answered here is as follows: Do the web-based virtual experiments developed for supplementation of physical laboratory instruction enhance students' knowledge of experimental procedure and data acquisition? This question is answered by assessing the performance of a "control" group of students that did not use "eLIVE" and comparing it with the performance of an "experimental" group that availed "eLIVE" prior to the physical experiment sessions. Students' performance in tests and quizzes administered to both the groups prior to the physical experiments was analyzed, using a non-parametric statistical method, to establish the statistical significance of assessed results with respect to "eLIVE" intervention, and demographic parameters such as gender, ethnicity, academic achievement, age, course load etc. Statistical results as well as students' response to surveys presented in this work point to "eLIVE" as being a very useful technology- enhanced interactive learning tool. The present study clearly establishes the pedagogy of physical laboratory supplementation with web-based virtual laboratories on a firm ground for possible extension to other engineering laboratory courses at ODU as well as at other institutions. [ABSTRACT FROM AUTHOR]

The nursing department at Norfolk State University (NSU), a historically Black university located in Norfolk, Virginia, designed a program to increase the retention and success of foreign-born students challenged with English as a Second Language (ESL). Through strategies designed to address language, social, academic, and personal challenges, the program has led to improvements in student satisfaction and performance. This article reviews the literature related to educating foreign-born nursing students in the United States, discusses unique considerations for these students within minority-serving institutions, describes key components of program development, and evaluates NSU's program. To increase the diversity of the nursing workforce, other institutions are encouraged to consider replicating NSU's model for ESL-student retention and success. [ABSTRACT FROM AUTHOR]

Soil samples were collected from Norfolk, Virginia in order to examine the extent of particulate coal, and associated arsenic (As) deposition to local soils. The particulate coal originates from the adjacent coal shipping terminal at the Lambert’s Point Docks, which is the largest marine coal shipping terminal in the Northern Hemisphere. Particulate coal was separated from soil samples using heavy liquid (i.e., sodium polytungstate) extraction. Sand-sized coal separates isolated from the soil samples were subsequently digested using concentrated nitric and sulfuric acid, and analyzed for As by high-resolution inductively coupled plasma mass spectrometry (HR-ICP-MS). Selected total soil digests were also analyzed for As by HR-ICP-MS. Results indicate particulate coal ranges from less than 1% up to ∼20%, by weight, of the soil samples analyzed. Arsenic concentrations in sand-sized particulate coal extracted from these sediments range from undetectable levels (i.e., <3 ng/kg) up to 17.4 mg/kg, whereas total As concentrations in the soils range from 3 to 30.5 mg/kg. The data indicate that particulate coal originating at the Lambert’s Point Docks is an additional source of As to local soils, especially sites proximal to the shipping terminal. Although the particulate coal itself likely poses only minor health hazards (if any), the environmental consequences of As transported with the particulate coal is not known. [ABSTRACT FROM AUTHOR]

A numerical model detailing the functioning and emergent behaviour of an eroding coastal system is described. Model output from a 50-km study region centred on the soft-rock shore of northeast Norfolk was verified through comparison with cliff recession rates that were extracted from historical maps spanning more than a century. Predictions were then made for the period 2000 to 2100 under combined climatic change and management scenarios. For the scenarios evaluated, the model was relatively insensitive to increases in offshore wave height and moderately sensitive to changes in wave direction, but the most important effects were associated with accelerated sea-level rise (SLR). In contrast to predictions made using a modified version of the Bruun rule, the systems model predicted rather complex responses to SLR. For instance, on some sectors of coast, whereas the Bruun rule predicted increased recession under accelerated SLR, the systems model actually predicted progradation owing to the delivery of sediment from eroding coasts up-drift. By contrast, on coasts where beaches are underlain by shore platforms, both the Bruun rule and the systems model predicted accelerated recession rates. However, explicit consideration of the interaction between beach and shore platform within the systems model indicates that these coasts have a broader range of responses and lower overall vulnerability to SLR than predicted by the Bruun rule. [ABSTRACT FROM AUTHOR]

Poor air quality represents a significant health risk for individuals engaging in recreation activities outdoors in urban parks and trails. This study investigated temporal variability in particulate matter (PM) exposure along an urban waterfront trail. We also used recreation choice frameworks to examine the effects of visitors' perceptions of air quality (AQ) and health benefits on trail use. Average air quality during the collection period was "good" (PM10) to "moderate" (PM2.5). We found that PM density was significantly higher (p < 0.001), though still in the "moderate" range, at 7–9 a.m., 11 a.m.–1 p.m., and 3–5 p.m., and on weekends. Visitors' self-reported perceptions of health outcomes, but not air quality, significantly predicted trail use. Results suggest that these experiential factors may affect recreational choices depending on other factors, such as salience. Further research is merited to determine how experiential factors can be integrated with other theories of motivation to understand recreational decision-making. [ABSTRACT FROM AUTHOR]

The article discusses the U.S. Navy squadrons with the focus on the VAW-12, a Carrier Airborne Early Warning (AEW) squadron established at naval air station (NAS) in Norfolk, Virginia. It mentions the Replacement Air Group Squadron RVAW-120 established to train aviators and enlisted personnel in carrier-based AEW aircraft. It adds views of former U.S. Navy lieutenant commander (LCDR) Henry G. Bozeman on flying a WF-1 Tracer plane.

Explores the implications of full-text electronic journals in libraries. Investigation if electronic-for-print journal substitutions have an impact on print subscriptions; Pilot project held at the Old Dominion University Library in Norfolk, Virginia; Real and potential cost savings for libraries.

Features the Public School Restructuring for Innovative Mainstream Education (PRIME) school reform initiative of Old Dominion University and Norfolk, Virginia Public Schools. Goals of PRIME; Components of PRIME; Other attributes of PRIME: Evaluation system of PRIME.

The article investigates the problem-solving strategies of sixth-grade students who are superior problem solvers by researchers from Norfolk, Virigina. In this study, the researchers attempt to find common problem-solving behaviors and strategies used by the subjects across several types of problems. The use of audiotaped problem-solving sessions appear to be an effective method for discovering how subjects solve problems. The use of predesigned behaviors classification scheme, such as the one employed in this study, makes it possible to discover the problem-solving behaviors and strategies of individuals and groups.

The article profiles John F. Oliviera Fernandez, an immigrant Portuguese physician and lay trustee of St. Mary's congregation in Norfolk, Virginia. He has been influenced by the effects of the Enlightenment on the European Catholic church that provided a fertile ground for theological reflection and ecclesiastical adaptation in American Catholicism. Fernandez has also been involved in the immigrant Catholic congregation's affairs and became the congregation's chief spokesman in 1820.

The article presents an application of motivator-hygiene theory among the black, working poor. Briefly stated, the motivator-hygiene theory demonstrates that man has two separate and independent need systems that do not interact. The hygiene continuum deals with man's need to avoid pain from his environment and is met by increasing extrinsic job factors such as salary, status, company policy and administration, good interpersonal relationships, etc. It is the hygiene factors that keep man from states of dissatisfaction. Thus, explicit to motivator-hygiene theory is the hypothesis that satisfaction and dissatisfaction are separate and independent conditions of job attitudes. The opposite of satisfaction is not dissatisfaction, rather, it is simply no satisfaction. The population sampled for this study consisted of a group of the black working poor in Norfolk, Virginia. This particular sample was chosen for several reasons. Since the study specifically attempts to ascertain attitudes about the work situation, it was only proper that interviews be held with some of those who were working. Poor and black workers were selected so as to ascertain whether or not this replication would further verify the motivator-hygiene theory, which had not yet been tested on such poor or black populations.

The hypothesis that radical segregationist sentiment is unevenly distributed within a city is partially confirmed by a study of attitudes in Norfolk, Virginia. Attitude toward school desegregation is found to differ significantly by social area type as defined by the Shevky-Bell scheme. The study also reveals the large size and stability of the moderate group on this issue. [ABSTRACT FROM AUTHOR]

Flooding in many areas is becoming more prevalent due to factors such as urbanization and climate change, requiring modernization of stormwater infrastructure. Retrofitting standard passive systems with controllable valves/pumps is promising, but requires real-time control (RTC). One method of automating RTC is reinforcement learning (RL), a general technique for sequential optimization and control in uncertain environments. The notion is that an RL algorithm can use inputs of real-time flood data and rainfall forecasts to learn a policy for controlling the stormwater infrastructure to minimize measures of flooding. In real-world conditions, rainfall forecasts and other state information are subject to noise and uncertainty. To account for these characteristics of the problem data, we implemented Deep Deterministic Policy Gradient (DDPG), an RL algorithm that is distinguished by its capability to handle noise in the input data. DDPG implementations were trained and tested against a passive flood control policy. Three primary cases were studied: (i) perfect data, (ii) imperfect rainfall forecasts, and (iii) imperfect water level and forecast data. Rainfall episodes (100) that caused flooding in the passive system were selected from 10 years of observations in Norfolk, Virginia, USA; 85 randomly selected episodes were used for training and the remaining 15 unseen episodes served as test cases. Compared to the passive system, all RL implementations reduced flooding volume by 70.5% on average, and performed within a range of 5%. This suggests that DDPG is robust to noisy input data, which is essential knowledge to advance the real-world applicability of RL for stormwater RTC. [ABSTRACT FROM AUTHOR]

Submarine canyons are often morphologically complex features in the deep sea contributing to habitat heterogeneity. In addition, they act as major conduits of organic matter from the shallow productive shelf to the food deprived deep-sea, promoting gradients in food resources and areas of sediment resuspension and deposition. This study focuses on the Baltimore and Norfolk canyons, in the western North Atlantic Ocean, and investigates how different biogeochemical drivers influence canyon and slope macrofaunal communities. Replicated sediment cores were collected along the main axes (~180–1200 m) of Baltimore and Norfolk canyons and at comparable depths on the adjacent slopes. Cores were sorted, assessing whole community macrofaunal (>300 μm) abundance, diversity and standing stocks. Canyon communities were significantly different from slope communities in terms of diversity, abundance patterns and community assemblages, which were attributed to high levels of organic matter enrichment within canyons. There was a significant departure from the expected density-depth relationship in both canyons, driven by enhanced abundances between 800 and 900 m canyon depths, which was characterised as a deposition zone for organic matter. Bathymetric zonation, sediment dynamics, organic enrichment, and disturbance events were clear factors that structured the benthic communities in both Baltimore and Norfolk canyons. Coupling family-level community data, with sediment grain-size and biogeochemistry data explained community dynamics across depth and biogeochemical gradients, providing further evidence that canyons disrupt macrofaunal diversity and density patterns in the deep-sea benthos. • Canyons are important hotspots of macrofaunal biodiversity. • Sedimentary & organic enrichment processes play important roles ecological patterns within the confines of canyon systems. • Two neighbouring canyons contained distinct macrofaunal communities. • Canyon abundance, diversity and community composition patterns were different from adjacent slopes. • Biomass and average body size were not conclusively shown to be enhanced in the canyons at all depths. [ABSTRACT FROM AUTHOR]