Looking Back, Looking Forward: A New Look at the Historic Resources of the Maryland Port Towns

This document has had referenced material removed in respect for the owner's copyright. A complete version of this document, which includes said referenced material, resides in the University of Maryland, College Park's library collection.During the fall of 2008, the historic preservation studio of the University of Maryland’s Graduate Program in Historic Preservation developed a heritage resource study for the Maryland Port Towns, a group of four individual municipalities located on the Anacostia River in Prince George’s County, Maryland. The client, the Port Towns Community Development Corporation, made it clear from the beginning that the study was to dovetail with their already extensive efforts for social and economic development in the Port Towns. The study that follows is the culmination of the efforts of the nine-member studio team. Titled Looking Back, Looking Forward: A New Look at the Heritage Resources of the Maryland Port Towns, the study initially developed from two principal questions: • What existing historic resources are located in the Port Towns? • What can be done to preserve, enhance, and highlight the existing historic resources located in the Port Towns to meet the socioeconomic goals set by the Port Towns Community Development Corporation

Mapping Groundwater Dependent Ecosystems in California

BACKGROUND: Most groundwater conservation and management efforts focus on protecting groundwater for drinking water and for other human uses with little understanding or focus on the ecosystems that depend on groundwater. However, groundwater plays an integral role in sustaining certain types of aquatic, terrestrial and coastal ecosystems, and their associated landscapes. Our aim was to illuminate the connection between groundwater and surface ecosystems by identifying and mapping the distribution of groundwater dependent ecosystems (GDEs) in California. METHODOLOGY/PRINCIPAL FINDINGS: To locate where groundwater flow sustains ecosystems we identified and mapped groundwater dependent ecosystems using a GIS. We developed an index of groundwater dependency by analyzing geospatial data for three ecosystem types that depend on groundwater: (1) springs and seeps; (2) wetlands and associated vegetation alliances; and (3) stream discharge from groundwater sources (baseflow index). Each variable was summarized at the scale of a small watershed (Hydrologic Unit Code-12; mean size = 9,570 ha; n = 4,621), and then stratified and summarized to 10 regions of relative homogeneity in terms of hydrologic, ecologic and climatic conditions. We found that groundwater dependent ecosystems are widely, although unevenly, distributed across California. Although different types of GDEs are clustered more densely in certain areas of the state, watersheds with multiple types of GDEs are found in both humid (e.g. coastal) and more arid regions. Springs are most densely concentrated in the North Coast and North Lahontan, whereas groundwater dependent wetlands and associated vegetation alliances are concentrated in the North and South Lahontan and Sacramento River hydrologic regions. The percentage of land area where stream discharge is most dependent on groundwater is found in the North Coast, Sacramento River and Tulare Lake regions. GDE clusters are located at the highest percentage in the North Coast (an area of the highest annual rainfall totals), North Lahontan (an arid, high desert climate with low annual rainfall), and Sacramento River hydrologic regions. That GDEs occur in such distinct climatic and hydrologic settings reveals the widespread distribution of these ecosystems. CONCLUSIONS/SIGNIFICANCE: Protection and management of groundwater-dependent ecosystems are hindered by lack of information on their diversity, abundance and location. By developing a methodology that uses existing datasets to locate GDEs, this assessment addresses that knowledge gap. We report here on the application of this method across California, but believe the method can be expanded to regions where spatial data exist

A Comprehensive Spectral and Variability Study of Narrow-Line Seyfert 1 Galaxies Observed by ASCA: I. Observations and Time Series Analysis

(Abridged) I present a comprehensive and uniform analysis of 25 {\it ASCA} observations from 23 Narrow-line Seyfert 1 galaxies. The time series analysis is presented in this paper, Part 1, and the spectral analysis and correlations are presented in the companion paper, Part 2.Comment: 51 pages, 32 figures, accepted for publication in ApJS. Report also available also at http://www.astro.columbia.edu/~leighly/research.htm

The Inner-Shelf Dynamics Experiment

17 USC 105 interim-entered record; under review.The article of record as published may be found at http://dx.doi.org/10.1175/BAMS-D-19-0281.1The inner shelf, the transition zone between the surfzone and the midshelf, is a dynamically complex region with the evolution of circulation and stratification driven by multiple physical processes. Cross-shelf exchange through the inner shelf has important implications for coastal water quality, ecological connectivity, and lateral movement of sediment and heat. The Inner-Shelf Dynamics Experiment (ISDE) was an intensive, coordinated, multi-institution field experiment from September–October 2017, conducted from the midshelf, through the inner shelf, and into the surfzone near Point Sal, California. Satellite, airborne, shore- and ship-based remote sensing, in-water moorings and ship-based sampling, and numerical ocean circulation models forced by winds, waves, and tides were used to investigate the dynamics governing the circulation and transport in the inner shelf and the role of coastline variability on regional circulation dynamics. Here, the following physical processes are highlighted: internal wave dynamics from the midshelf to the inner shelf; flow separation and eddy shedding off Point Sal; offshore ejection of surfzone waters from rip currents; and wind-driven subtidal circulation dynamics. The extensive dataset from ISDE allows for unprecedented investigations into the role of physical processes in creating spatial heterogeneity, and nonlinear interactions between various inner-shelf physical processes. Overall, the highly spatially and temporally resolved oceanographic measurements and numerical simulations of ISDE provide a central framework for studies exploring this complex and fascinating region of the ocean.U.S. Office of Naval Research (ONR)ONR Departmental Research Initiative (DRI)Inner-Shelf Dynamics Experiment (ISDE

A comparison of the gobiid fauna between a shoal and an island habitat in the central Visayas (Philippines)

We surveyed the marine gobies of Malapascua island (Philippines), the surrounding islets and the nearby Monad shoal. We found 59 species in 19 genera, including 2 undescribed species of the genus Trimma, and 3 geographic and 6 depth range expansions. Furthermore we describe a new type of mimicry between the goby Koumasetta hectori and the cardinalfish Apogon nigrofasciatus. The comparison of the island versus shoal goby fauna showed a lesser species richness of shrimpassociated gobies at the shoal. This likely reflects the fact that hydrodynamic features of the environment play a dominant role in selecting which gobiid species, or their symbiotic shrimp, will be found in a certain location. We also observed a bias towards hovering species (of the genus Trimma) and away from shrimp-associated gobies at greater depths. These findings are in accord with the suspected shift of gobies towards planctotrophy with increasing depth. We furthermore compare this study to previous surveys of goby faunas, and plot the recorded species numbers against the survey areas. This species-area plot provides support for the notion of high speciation rates in gobies due to their low mobility.</jats:p

Experimental investigation of the effect of steps and gaps on hypersonic vehicles

The design of hypersonic vehicles typically incorporates the use of simple, geometric shapes with smooth surfaces. There are many reasons why aircraft cannot have perfectly smooth surfaces with small, unavoidable imperfections frequently being present. These can appear in many forms, such as gaps between tiles and rivets joining different panels. Surface features like this are mainly detrimental to aircraft performance for two reasons: they can cause premature boundary layer transition, leading to higher integrated heat loads and unexpected aerodynamic loads; and they cause highly localised areas of heat flux augmentation – up to many times the undisturbed level. This work is part of a project which aims to characterise some of these effects using a combination of experimental and numerical techniques with the overall aim being to produce useful engineering level correlations for use in vehicle design. This paper presents initial experiments performed in the Oxford High Density Tunnel (HDT). Heat flux and pressure data have been acquired for a range of step and cavity geometries, and capability of a sophisticated experimental model has been shown