38 research outputs found

    History and heritage at James Madison’s Montpelier: significance and privileged narratives at historic sites

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    Masters final project submitted to the Faculty of the Historic Preservation Program, School of Architecture, Planning and Preservation, University of Maryland, College Park, in partial fulfillment of the requirements for the degree of Master of Historic Preservation. HISP 710/711 final project, May 2012.In 2003, the Montpelier Foundation began a massive restoration of the Montpelier mansion, the lifelong home of James Madison, founding father, fourth president, and architect of the Constitution. But there had also been eight subsequent owners in the 150 years that had passed, including members of the duPont family, who had made extensive changes to the house and landscape. The restoration removed all the non-Madison fabric from the house, but left the landscape as it was. This study examines the reasons why restoration was ultimately chosen over the preservation of the site at Montpelier. I explore the questions of why the Madison narrative was selected as most important and why the stories of our presidents are privileged over all others? After examining the vast duPont landscape, I create a walking tour to interpret the duPont narrative. The project concludes with recommendations for how Montpelier’s story can be more inclusive of the site’s multiple narratives, and how these ideas can be used more broadly for interpretation at other historic sites

    Evaluacija citotoksičnosti resveratrola i piceatanola u makrofazima, T-stanicama i stanicama kože

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    The cytotoxicity of resveratrol and of piceatannol, a structural analog of resveratrol, was examined in cultured cells. Using a MTT-based assay, which measures the conversion of 3-[4,5-dimethylthiazol-2- yl]-2,5-diphenyl tetrazolium bromide (MTT) to a colored formazan product in living cells, resveratrol was found to inhibit the viability of transformed mouse macrophages, tumor-derived human T cells and human epidermoid carcinoma cells in a concentration-dependent manner, with the effect decreasing in the order: T cells (LC50 ~27 µmol L-1, 24 h; ~9 µmol L-1; 48h) > macrophages (LC50 ~29 µmol L-1, 24 h; 39 µmol L-1, 48 h) > skin cells (LC50 ~91 µmol L-1, 24 h ; ~66 µmol L-1, 48 h). Paradoxically, a high concentration of resveratrol (50 µmol L-1) inhibited the proliferation of all three cell types, and a low concentration (5 µmol L-1) stimulated the proliferation of macrophages. The viability of macrophages was also decreased by piceatannol in a concentration-dependent manner. The stimulation of macrophages with zymosan lowered the cytotoxicity of both resveratrol and piceatannol. Scanning electron microscopy of cells treated with resveratrol revealed changes in cellular morphology that were consistent with toxicity. In macrophages and skin cells, resveratrol (50 µmol L-1) induced a time-dependent increase in reduced glutathione levels but did not alter the background levels of thiobarbituric acid-reactive substances. Taken together, the present data indicate that resveratrol is toxic to cultured macrophages, T cells and skin cells at concentrations ≥25 µmol L-1, and that the cytotoxicity occurs via a mechanism that does not involve oxidative stress. Furthermore, the degree of toxicity of both resveratrol and piceatannol towards macrophages depends on the activation status of these cells, with zymosan-activated cells appearing more resistant than nonstimulated cells.Citotoksičnost resveratrola i piceatanola, strukturnog analoga resveratrola, ispitivana je u uzgojenim stanicama. Primjenom MTT-testa koji mjeri pretvorbu 3-[4,5-dimetiltiazol-2-il]2,5-difenil-tetrazolijeva bromida (MTT) u obojeni formazan produkt u živim stanicama, na|eno je da resveratrol inhibira preživljavanje transformiranih makrofaga miša, ljudskih tumorskih T-stanica i humanih stanica epidermoidnog karcinoma u ovisnosti o koncentraciji, a učinak opada redom: T-stanice (LC50 ~27 µmol L-1, 24 h; ~9 µmol L-1; 48 h) > makrofazi (LC50 ~29 µmol L-1, 24 h; 39 µmol L-1, 48 h) >stanice kože (LC50 ~91 µmol L-1, 24 h; ~66 µmol L-1, 48 h). Paradoksalno, pri visokoj koncentraciji resveratrola (50 µmol L-1) inhibirana je proliferacija svih triju tipova stanica, a pri niskim koncentracijma (5 µmol L-1) stimulirana je proliferacija makrofaga. Preživljavanje makrofaga bilo je tako|er smanjeno primjenom piceatanola ovisno o koncentraciji. Stimulacija makrofaga zimosanom smanjila je citotoksičnost i resveratrola i piceatanola. Skenirajuća elektronska mikroskopija stanica tretiranih resveratrolom pokazala je promjene u morfologiji stanica, što je bilo u skladu s toksičnosti. U makrofazima i stanicama kože resveratrol (50 µmol L-1) inducirao je porast smanjenja razina glutationa ovisan o vremenu, ali nije mijenjao osnovne razine reaktivnih spojeva tiobarbiturne kiseline. Gledajući skupno, prikazani rezultati indiciraju da je resveratrol toksičan za uzgojene makrofage, T-stanice i stanice kože pri koncentracijama ≥25 µmol L-1 i da se citotoksičnost zbiva mehanizmom koji ne uključuje oksidativni stres. Nadalje, stupanj toksičnosti resveratrola i piceatanola prema makrofagima ovisi o aktivacijskom statusu tih stanica, pri čemu su stanice aktivirane zimosanom rezistentnije od nestimuliranih stanica

    On determination of statistical properties of spectra from parametric level dynamics

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    We analyze an approach aiming at determining statistical properties of spectra of time-periodic quantum chaotic system based on the parameter dynamics of their quasienergies. In particular we show that application of the methods of statistical physics, proposed previously in the literature, taking into account appropriate integrals of motion of the parametric dynamics is fully justified, even if the used integrals of motion do not determine the invariant manifold in a unique way. The indetermination of the manifold is removed by applying Dirac's theory of constrained Hamiltonian systems and imposing appropriate primary, first-class constraints and a gauge transformation generated by them in the standard way. The obtained results close the gap in the whole reasoning aiming at understanding statistical properties of spectra in terms of parametric dynamics.Comment: 9 pages without figure

    Feasibility study for future use of the Bostwick property

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    University of Maryland School of Architecture, Planning & Preservation, Graduate Program in Historic Preservation, December 2011. HISP 650Since its construction in 1746, Bostwick has been a constant presence in Bladensburg, Maryland. It has survived as a standing structure with several acres of intact historic landscape, while the built environment of the surrounding area has evolved. The original structure, many of the historic outbuildings, and the landscape remain, but throughout its history Bostwick’s buildings and landscape have changed in appearance, function, and its relationship to the local community. Today, the property is physically deteriorating, and damage from the August 2011 earthquake has only made the situation worse. It has become a problem for both its owner, the Town of Bladensburg, and the greater preservation community. All involved are interested in Bostwick’s survival, and all agree that its potential future use could be the cornerstone in Bladensburg’s continuing development. As part of an ongoing relationship between the University of Maryland and the Town, this studio project was developed to explore recommendations for a new use of Bostwick. The recommended scenario builds upon the strengths of the Bladensburg community and the unique heritage of Bostwick. This report is divided into two parts: (1) Research & Assessment and (2) Recommendations. Part 1 details all of our research, including the past and present context of both Bostwick and greater Bladensburg, previous preservation efforts and studies, stakeholder values, and comparable sites. All of this data informs Part 2 of this report, which contains our recommendations for the future use of Bostwick

    Effect of raw and purified carbon nanotubes and iron oxide nanoparticles on the growth of wheatgrass prepared from the cotyledons of common wheat (triticum aestivum)

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    The increase in global production of nanomaterials has raised concern as to their possible effects on plants that could ultimately affect the human population. The effects on the hydroponic growth of wheatgrass of four types of nanomaterials were studied: raw-single walled carbon nanotubes (SWCNTs), purified-SWCNTs, multi walled carbon nanotubes (MWCNTs), and iron oxide nanoparticles (n-FeOx) as a model of the catalyst residue typically present in CNTs. The germination rate (GR), mean germination time (MGT), shoot length, and a visual score of the plants' growth were determined for wheatgrass over the course of two weeks as a function of exposure to the nanomaterials dispersed in either water or THF (as well as appropriate controls). Raw-SWCNTs, MWCNTs, and n-FeOx show little impact suggesting that the catalyst residue (iron oxide) present in CNTs has little effect. Exposure to purified-SWCNTs dispersed in water shows increased GR (and shoot length), while wheatgrass exposed to purified-SWCNT dispersed in THF had retarded GR, suggesting that SWCNTs act as a carrier for adsorbed organic solvents whose effects are detrimental. A similar but lesser effect was observed for MWCNTs. Interestingly raw-SWCNTs showed no solvent effect, suggesting that the reduction of hydrophobicity of the SWCNTs through functionalisation enables the adsorption and subsequent release of harmful organic solvents. The positive effect of purified SWCNTs when dispersed in water is likely a function of their highly hydrophobic nature facilitating enhanced uptake of water

    Ecological and hydrological values of small water reservoirs in the Białowieża Forest

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    W ostatnich latach na terenie Puszczy Białowieskiej notuje się stałe obniżanie się zwierciadła wód gruntowych. Proces ten jest spowodowany m.in. pracami melioracyjnymi wykonanymi w latach 50. i 60. ubiegłego wieku. Regulacja cieków oraz budowa rowów melioracyjnych przyśpieszyły odpływ wody. Efektem zaburzenia warunków wodnych na tym obszarze jest przesuszenie mokradłowych siedlisk leśnych, a w rezultacie grądowienie olsów i łęgów. W celu poprawy warunków wodnych mokradłowych obszarów leśnych na terenie Puszczy Białowieskiej (poza obszarem parku narodowego), z inicjatywy PTOP (Północnopodlaskie Towarzystwo Ochrony Ptaków), wybudowano kilkadziesiąt małych zbiorników wodnych różnych typów. Zbiorniki w zlewniach zalesionych powstały poprzez przegrodzenie naturalnych cieków bądź rowów progiem-bystrotokiem, natomiast zbiorniki śródpolne wykopano. Oczekuje się, że powyższe działania wpłyną korzystnie na wydłużenie okresu stagnacji wód roztopowych, co zapobiegnie wysychaniu niektórych cieków w okresie lata. Umożliwią one również przywrócenie i powstanie nowych miejsc rozrodu płazów oraz utrzymanie bazy pokarmowej dla ptaków obszarów mokradłowych, m.in. bociana czarnego (Ciconia nigra L.). W pracy przedstawiono ocenę warunków ekologicznych i hydrologicznych zbiorników w zlewni Narewki. Przeprowadzono podstawowe pomiary jakości wody i stanu roślinności ekotopu oraz lustra wody wybranych zbiorników. W wielu przypadkach stwierdzono wkraczanie roślinności siedlisk mokradłowych oraz wypadanie gatunków grądowych i borowych. W okresie wiosennym zaobserwowano wykorzystanie stworzonych miejsc lęgowych przez płazy oraz obecność bociana czarnego (Ciconia nigra L.). W wyniku budowy małych zbiorników wodnych poprawiły się warunki do istnienia siedlisk olsowych i łęgowych.Constant decline of groundwater levels has recently been observed in the Białowieża Forest . This process is due to drainage which took place in the 1950s and 1960s. Regulation of watercourses and construction of drainage canals and ditches caused the increase of water discharge from the area and drying of wetland forest habitats: riparian forests and alder carr. In order to improve water conditions for wetland forests in the area of the Białowieża Forest (outside the Białowieża National Park ) several dozen small water reservoirs were built by PTOP (North-Podlasie Association of Bird Protection). Some of them were made by damming watercourses and the midfield ponds were just dug out. These actions were expected to prolong the stagnation period of melting waters in the bed of watercourses, to create breeding places for amphibians and to provide food resources for waterfowl like e.g. black stork (Ciconia nigra L.). The study was focussed on ecological and hydrological conditions of small water reservoirs in the Narewka river catchment. The paper presents the description of plants, which have overgrown water reservoirs and their neighbourhood, the size of reservoirs and basic analyses of water quality. In most cases typical species for wetlands forest were observed, which was the evidence for the improvement of hydrologic conditions for riparian forests and alder carr. Moreover, water reservoirs were inhabited by waterfowl and used as breeding places by amphibians
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