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Perineuronal nets (PNNs) are specialized extracellular matrix structures that surround subsets of neurons throughout the central nervous system (CNS). They are made up of chondroitin sulfate proteoglycans (CSPGs), hyaluronan, tenascin-R, and many other link proteins that together make up their rigid and lattice-like structure. Modulation of PNNs can alter synaptic plasticity and thereby affect learning, memory, and cognition. In the present study, we degraded PNNs in the medial prefrontal (mPFC) and posterior parietal (PPC) cortices of Long-Evans rats using the enzyme chondroitinase ABC (ChABC), which cleaves apart CSPGs. We then measured the consequences of PNN degradation on spatial working memory (WM) with a trial-unique, non-matching-to location (TUNL) automated touchscreen task. All rats were trained with a standard 6 sec delay and 20 sec inter-trial interval (ITI) and then tested under four different conditions: a 6 sec delay, a variable 2 or 6 sec delay, a 2 sec delay with a 1 sec ITI (interference condition), and a 20 sec delay. Rats that received mPFC ChABC treatment initially performed TUNL with higher accuracy, more selection trials completed, and fewer correction trials completed compared to controls in the 20 sec delay condition but did not perform differently from controls in any other condition. Rats that received PPC ChABC treatment did not perform significantly differently from controls in any condition. Posthumous immunohistochemistry confirmed an increase in CSPG degradation products (C4S stain) in the mPFC and PPC following ChABC infusions while WFA staining intensity and parvalbumin positive neuron number were decreased following mPFC, but not PPC, ChABC infusions. These findings suggest that PNNs in the mPFC play a subtle role in spatial WM, but PNNs in the PPC do not. Furthermore, it appears that PNNs in the mPFC are involved in adapting to a challenging novel delay, but that they do not play an essential role in spatial WM function.

Understory plants are often inadequately represented or neglected within analyses of forest ecosystem productivity. Further, the potential impacts of the biological factors of age class and growth form on carbon cycling physiology, and how it may vary across the growing season and amongst species of different native/non-native status, have not been thoroughly considered. Our study examines photosynthesis and associated physical leaf traits in two understory woody species, Rhamnus cathartica , introduced and invasive in North America, and Prunus serotina , a common subcanopy species native to North America. We estimated leaf-level photosynthesis as measured through light and carbon dioxide response curves, dark-adapted chlorophyll fluorescence and leaf traits (leaf mass per area and stomatal density) for each combination of species and age class at plots in the understory of a temperate deciduous research forest in the US Upper Midwest at two time points during the growing season, late spring (late May) and mid-summer (mid-July). Carbon assimilation rates from light response curves (A sat, A 400) and fluorescence capacity estimate F v/ F m all increased between the two measurement points in both species and age class. Estimates of carbon reaction capacity (V cmax and J max) exhibited a different directional response to seasonal development, declining in seedlings of both species and P. serotina trees (~8–37 % reduction in V cmax, ~9–34 % reduction in J max), though increased in trees of R. cathartica (+24 % in V cmax, +9 % in J max). Divergent responses in photosynthetic parameters amongst these factors may be explained by species differences in leaf mass per area and stomatal density, which together are likely influenced by both growth form, canopy position and ontogeny. Overall, we believe our findings suggest complex, varied influences on photosynthesis that indicate environmental and biological plasticity which may contribute to the historic and continued expansion of R. cathartica in the US Upper Midwest region. [ABSTRACT FROM AUTHOR]

This paper focuses on analyzing traffic facilities for an intermediate time frame. There are two methodologies examined in this work, the first uses extrapolated, historical traffic count data and the second uses an urban transportation model. Using several intersections within Huntsville, Ala., as case study intersection locations, this paper applies both methodologies to forecast near-future traffic and compares the forecasted results with the actual traffic counts to determine which methodology better replicated actual volumes. The results of this work indicate that a properly validated and applied urban transportation planning model has the ability to provide more accurate traffic forecasts to support the traffic engineering analysis decision than the commonly used extrapolated traffic trends. CE Database subject headings: Traffic models; Traffic engineering; Forecasting; Traffic analysis; Urban planning.

This paper examines a new methodology to predict external trip exchanges in small urban communities. The paper documents a study performed on several small communities in Alabama and includes a video surveillance data collection methodology, data analysis, model development, and test versus existing models. The new model presented in this paper is shown to provide more accurate results when compared to existing models and demonstrated transferability to a similar city. DOI: 10.1061/(ASCE)0733-9488(2006) 132:2(112) CE Database subject headings: Methodology; Urban areas; Alabama; Traffic surveillance; Transportation management.

The structure of precursors is used to control the formation of six possible structural isomers that contain four structural units of PbSe and four structural units of NbSe2: [(PbSe)1.14]4[NbSe2]4, [(PbSe)1.14]3[NbSe2]3[(PbSe)1.14]1[NbSe2]1, [(PbSe)1.14]3[NbSe2]2[(PbSe)1.14]1[NbSe2]2, [(PbSe)1.14]2[NbSe2]3[(PbSe)1.14]2[NbSe2]1, [(PbSe)1.14]2[NbSe2]2[(PbSe)1.14]1[NbSe2]1[(PbSe)1.14]1[NbSe2]1, [(PbSe)1.14]2[NbSe2]1[(PbSe)1.14]1[NbSe2]2[(PbSe)1.14]1[NbSe2]1. The electrical properties of these compounds vary with the nanoarchitecture. For each pair of constituents, over 20 000 new compounds, each with a specific nanoarchitecture, are possible with the number of structural units equal to 10 or less. This provides opportunities to systematically correlate structure with properties and hence optimize performance. [ABSTRACT FROM AUTHOR]

The ability to determine the volumes of freight (specifically trucks) passing through a state or metropolitan area is difficult to determine/forecast because transportation professionals have no direct survey mechanism to collect this data. This paper documents various procedures developed to utilize the Freight Analysis Framework Version 2 Database to determine the number of trucks passing through the entire state and an urban area in Alabama. The procedures developed in this research focus on national level pass through data, trips from one state to another that pass through a state only because of that state's location; pass through from a port of entry to the country where an urbanized area is located on a major corridor; and statewide level through trip data, trips from one part of a state to another that pass through an urbanized area because of its geographic location. The need for, and application of, the pass through freight forecasting is evident in the transportation planning models each metropolitan area and state are expected to develop and maintain for evaluating transportation projects. The ability to accurately forecast the pass through freight movements will benefit transportation planners by identifying freight volumes that must be accommodated by existing and proposed infrastructure, but for which the state or metropolitan area has no direct method to survey. [ABSTRACT FROM AUTHOR]

Preparingnew ternary compounds via traditional high temperaturesynthesis techniques is essentially limited to ternary compounds thatare thermodynamically more stable than any mixture of binary compoundsbecause binary compounds typically form as reaction intermediates.By using a precursor having elemental layers thinner than a criticalthickness, it is possible to decrease diffusion times such that thelayers interdiffuse before nucleation of binary compounds occurs atreacting interfaces. To nucleate the ternary compounds CuInSe2and CuCr2Se4directly from amorphousreaction intermediates, however, it is shown to be necessary to usethe order of the elemental layers to control of the order of mixingof the elemental layers. Controlling layer thickness and layer sequenceis a general strategy for avoiding binary compounds as reaction intermediates,providing a general approach to preparing kinetically stable ternarycompounds. [ABSTRACT FROM AUTHOR]

Anorganische Nanokristalle: Die Strukturen der Verbindungen [(PbSe)1.00]m(MoSe2)n und [(PbSe)0.99]m(WSe2)n (m≥1 und n≤5) wurden mit Röntgenbeugung und Raster ‐ Transmissionselektronenmikroskopie untersucht. Sie weisen eine Paarungsverzerrung der PbSe ‐ Komponente auf, die abhängig ist von der Dicke der PbSe ‐ Schicht (m), aber unabhängig von Dicke des Dichalkogenids (n). [ABSTRACT FROM AUTHOR]

The structures of three new misfit layer compounds, [(PbSe)0.99]1[WSe2]1, [(PbSe)1.00]1[MoSe2]1, and [(SnSe)1.03]1[MoSe2]1, prepared as thin films from designed elementally modulated reactant precursors, have been investigated by synchrotron X-ray diffraction and scanning transmission electron microscopy. This is the second report of a misfit layer compound based on tin selenide and the first structure determinations of tungsten- and molybdenum-containing misfit layer compounds. The compounds have mismatches in both the a- and b-axis (in-plane) lattice parameters of the component structural units, which result in misfit parameters, δ, both greater and smaller than zero. Pole figures of hk0-type reflections indicate that c-axis-oriented (basal plane) dichalcogenide-structured units are randomly oriented within the a- b plane. The widths of diffraction peaks of type hk0, 00 l, and hkl ( h, k ≠ 0; l ≠ 0) indicate coherence lengths of approximately (6 to 7) nm within the a- b plane, the full thickness of the film along the c-axis, and (1 to 2) nm in mixed-index directions, respectively, consistent with random rotational disorder between the constituents, commonly termed turbostratic disorder in the clay literature. The intensities of 00 l- and hk0-type diffraction peaks were modeled to determine the structure of atomic planes along the c axis and the projection of the constituent structures onto the a- b plane, respectively. [ABSTRACT FROM AUTHOR]

Recently there has been interest in developing imaging contrast media for magnetic resonance imaging (MRI) that contain biologically rare, magnetically active nuclei such as fluorine. In principle, fluorinated contrast agents can be used to generate highly selective 19F magnetic resonance images that can be superimposed over complimentary 1H magnetic resonance images to provide an anatomical context for the fluorinated contrast agent. Additionally, nanoparticles can be made to target various pathological sites via active and passive targeting mechanisms. In this study, fluorinated nanoparticles were produced using a free radical polymerization of vinyl formamide monomers with two different fluorinated monomers. The nanoparticles showed a clear, single 19F-NMR signal. Additionally, surface amide groups were hydrolyzed to primary amines to yield additional surface reactivity. Fluorinated nanoparticles produced using a free-radial polymerization method yield a new nanoparticle for 19F-MRI applications with potential for facile functionalization. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 [ABSTRACT FROM AUTHOR]

Abstract: Atomized silver spheres (≤53μm diameter) were coated with a 1μm thick layer of (La0.6Sr0.4)0.98Co0.2Fe0.8O3−δ via a mechanofusion dry processing method. The material was successfully utilized as an SOFC cathode on anode-supported YSZ electrolytes at 700°C, producing >500mWcm−2 (at 0.7V) and exhibiting relatively stable performance (∼3% power degradation per 1000h at 0.7V) during >2000h of operation. [Copyright &y& Elsevier]

(La0.8Sr0.2)0.98Fe0.98Cu0.02O3-δ can be sintered directly onto YSZ (without the need for a protective ceria interlayer). Though subject to an extended ‘burn-in’ period (∼200 h), anode-supported YSZ cells using the Cu-doped LSF achieve power densities ranging from 1.3 to 1.7 W/cm2 at 750°C and 0.7 V. These cells have also demonstrated 500 h of stable performance. The results are somewhat surprising given that XRD indicates an interaction between (La0.8Sr0.2)0.98Fe0.98-Cu0.02O3-δ and YSZ resulting in the formation of strontium zirconate and/or monoclinic zirconia. The amount and type of reaction product was found to be dependent on cathode and electrolyte powder precalcination temperatures. [ABSTRACT FROM AUTHOR]

This paper examines the practically of using a single internal trip purpose to generate the production and attraction values for traffic analysis zones in small urban community travel models. In previous research efforts, Quick-Response techniques, originally developed for cities with populations between 50,000 and 199,999, have been successfully applied to perform trip generation in small urban community travel models. Focusing on the reduction of data requirements and complexity of the trip generation analysis, a single trip purpose technique, based solely on aggregate numbers of households and businesses in a traffic analysis zone, has been proposed as a method to simplify the trip generation computation and reduce data requirements. This paper presents the fundamentals of the Quick-Response and single trip purpose techniques, tests the advantage of multiple trip purposes in a small sample network, and applies the two methodologies in a small urban community within Alabama to determine if significant differences exist when performing trip generation. The paper concludes that, for smaller urban community travel models, where different trip purposes are assumed to have similar trip lengths, both the Quick-Response and the single trip purpose technique produce similar results for the total productions and attractions in a traffic analysis zone. This similarity, and the results of the test showing that different trip purposes are not vital for trip distribution in small networks, substantiate the use of the simplified single trip purpose technique for trip generation. [ABSTRACT FROM AUTHOR]

Urban travel modeling techniques have not found widespread use in small urban communities because traditional forecasting models, designed for use in large urban cities, are very data intensive. In recent years, however, there has been a greater awareness of transportation problems occurring in small urban areas, which are generally defined as communities with a population less than 50,000. Previous transportation planning research efforts directed towards small urban areas have identified the need for planning techniques that are less data intense and less expensive to implement when compared with traditional transportation modeling methods. This paper presents an application of the urban transportation planning processes that has limited data collection and cost requirements, developed specifically for application in smaller urban areas. The data requirements are reduced through the use of a single internal trip purpose based on the total number of households and businesses in each traffic analysis zone. This single trip purpose forecasting technique was used to develop travel models for 18 Alabama cities with populations ranging between 5,000 and 55,000. Validation and analysis of the travel models show that the single internal trip purpose presented in this paper can accurately be used to forecast traffic in smaller areas without extensive data collection efforts. [ABSTRACT FROM AUTHOR]

The main difficulty in forecasting traffic volumes along a rural bypass is identifying the external traffic, both traffic entering the town from outside and traffic continuing through the town to an ultimate destination. Three methods exist for determining the percentage of external traffic destined for town, external-internal, or through town, external-external: A comprehensive origin-destination study, cordon line origin-destination study, or a regression equation. The objective of this paper is to examine the possibility of using different techniques, based on spatial economic models to determine the traffic percentages. This project will use three different models to determine the activity base for the city of Waverly, Iowa, and compare the models with the results given by the regression equation and a cordon line origin-destination study performed in the 1970s. This paper demonstrates that Huff's probability contour model performs well for the case study and recommends that this model be used in the future to provide estimates that incorporate a community's economic relationship to neighboring towns. [ABSTRACT FROM AUTHOR]

Describes the development and availability of desktop geographic information system (GIS)-based model for urban transportation planning. Applications of GIS in model development; GIS model development methodology; Steps in developing transportation network model.

I/O abstraction is offered as a new high-level approach to interprocess communication. Functional components of a distributed system are written as encapsulated modules that act upon local data structures, some of which may be published for external use. Relationships among modules are specified by logical connections among their published data structures. Whenever a module updates published data, I/O takes place implicitly according to the configuration of logical connections. The Programmers' Playground, a software library and run- time system supporting I/O abstraction, is described. Design goals include the separation of communication from computation, dynamic reconfiguration of the communication structure, and the uniform treatment of discrete and continuous data types. Support for end-user configuration of distributed multimedia applications is the motivation for the work. [ABSTRACT FROM AUTHOR]

A mechanistic understanding of the causes of naturalization in terrestrial plant communities, and the consequences for associated ecosystems, relies on understanding whether and how native and non‐native plant traits differ. Traits of non‐native plants may either help them compete or avoid competition with natives, and depending on their interaction with the native community, the non‐native may act as more or less of an active driver vs. a passive passenger of change in the native ecosystem. Trait comparisons between native and non‐native plants are often laboratory‐based, providing insights that can be difficult to apply to natural communities. Studies of the impacts of non‐native plants, by contrast, are generally performed in natural communities, but usually do not compare observed impacts of the non‐natives with those exerted by dominant natives on each other and the community. Thus, the likely relative disruption of the non‐native to the community is unclear. In a four‐year observational study conducted at the microhabitat scale in the herbaceous layer of a Midwestern oak forest, we compared the non‐native herb Alliaria petiolata (garlic mustard) with dominant native herbaceous species in terms of correlational patterns related to three broad categories of traits: (1) environmental correlates (light, topography, soil nutrients) with presence and cover, (2) inter‐annual regeneration and phenology, and (3) associations with other species (competition and herbivory). We found that Alliaria differed strongly from dominant native herbs in all three categories. Compared with native herbs, Alliaria was more strongly associated with south‐facing slopes and high nutrient levels, displayed earlier phenology and enhanced dispersal ability, and was strongly avoided by the generalist native herbivore, Odocoileus virginianus (white‐tailed deer). Despite well‐described allelopathic effects of Alliaria on mycorrhizae and mycorrhizal plants, we found little evidence to suggest that Alliaria had negative interactions with native plants that were stronger than those of native community members. Overall, our data suggest that naturalization of Alliaria in this site is primarily due to differences from native plants in phenology, dispersal capability, and avoidance of herbivory, and that Alliaria is therefore more likely to be acting as a passenger than as a driver of change in our site. [ABSTRACT FROM AUTHOR]

Extended abstract of a paper presented at Microscopy and Microanalysis 2010 in Portland, Oregon, USA, August 1 – August 5, 2010. [ABSTRACT FROM PUBLISHER]