923 resultados para Oriskany, Battle of, N.Y., 1777.
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Unique electrical and mechanical properties of single-walled carbon nanotubes (SWNTs) have made them one of the most promising candidates for next-generation nanoelectronics. Efficient utilization of the exceptional properties of SWNTs requires controlling their growth direction (e.g., vertical, horizontal) and morphologies (e.g., straight, junction, coiled). ^ In this dissertation, the catalytic effect on the branching of SWNTs, Y-shaped SWNTs (Y-SWNTs), was investigated. The formation of Y-shaped branches was found to be dependent on the composition of the catalysts. Easier carbide formers have a strong tendency to attach to the sidewall of SWNTs and thus enhance the degree of branching. Y-SWNTs based field-effect transistors (FETs) were fabricated and modulated by the metallic branch of the Y-SWNTs, exhibiting ambipolar characteristics at room temperature. A subthreshold swing of 700 mV/decade and an on/off ratio of 105 with a low off-state current of 10-13 A were obtained. The transport phenomena associated with Y- and cross-junction configurations reveals that the conduction mechanism in the SWNT junctions is governed by thermionic emission at T > 100 K and by tunneling at T < 100 K. ^ Furthermore, horizontally aligned SWNTs were synthesized by the controlled modification of external fields and forces. High performance carbon nanotube FETs and logic circuit were demonstrated utilizing the aligned SWNTs. It is found that the hysteresis in CNTFETs can be eliminated by removing absorbed water molecules on the CNT/SiO2 interface by vacuum annealing, hydrophobic surface treatment, and surface passivation. SWNT “serpentines” were synthesized by utilization of the interaction between drag force from gas flow and Van der Waals force with substrates. The curvature of bent SWNTs could be tailored by adjusting the gas flow rate, and changing the gas flow direction with respect to the step-edges on a single-crystal quartz substrate. Resistivity of bent SWNTs was observed to increase with curvature, which can be attributed to local deformations and possible chirality shift at curved part. ^ Our results show the successful synthesis of SWNTs having controllable morphologies and directionality. The capability of tailoring the electrical properties of SWNTs makes it possible to build an all-nanotube device by integrating SWNTs, having different functionalities, into complex circuits. ^
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This article will acquaint you with ten of the more important leftwing films I have reviewed over the past sixteen years as a member of New York Film Critics Online. You will not see listed familiar works such as “The Battle of Algiers” but instead those that deserve wider attention, the proverbial neglected masterpieces. They originate from different countries and are available through Internet streaming, either freely from Youtube or through Netflix or Amazon rental. In several instances you will be referred to film club websites that like the films under discussion deserve wider attention since they are the counterparts to the small, independent theaters where such films get premiered. The country of origin, date and director will be identified next to the title, followed by a summary of the film, and finally by its availability.
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Regarding General Valencia's conduct in the battle of Contreras.
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Wetland ecosystems provide many valuable ecosystem services, including carbon (C) storage and improvement of water quality. Yet, restored and managed wetlands are not frequently evaluated for their capacity to function in order to deliver on these values. Specific restoration or management practices designed to meet one set of criteria may yield unrecognized biogeochemical costs or co-benefits. The goal of this dissertation is to improve scientific understanding of how wetland restoration practices and waterfowl habitat management affect critical wetland biogeochemical processes related to greenhouse gas emissions and nutrient cycling. I met this goal through field and laboratory research experiments in which I tested for relationships between management factors and the biogeochemical responses of wetland soil, water, plants and trace gas emissions. Specifically, I quantified: (1) the effect of organic matter amendments on the carbon balance of a restored wetland; (2) the effectiveness of two static chamber designs in measuring methane (CH4) emissions from wetlands; (3) the impact of waterfowl herbivory on the oxygen-sensitive processes of methane emission and coupled nitrification-denitrification; and (4) nitrogen (N) exports caused by prescribed draw down of a waterfowl impoundment.
The potency of CH4 emissions from wetlands raises the concern that widespread restoration and/or creation of freshwater wetlands may present a radiative forcing hazard. Yet data on greenhouse gas emissions from restored wetlands are sparse and there has been little investigation into the greenhouse gas effects of amending wetland soils with organic matter, a recent practice used to improve function of mitigation wetlands in the Eastern United States. I measured trace gas emissions across an organic matter gradient at a restored wetland in the coastal plain of Virginia to test the hypothesis that added C substrate would increase the emission of CH4. I found soils heavily loaded with organic matter emitted significantly more carbon dioxide than those that have received little or no organic matter. CH4 emissions from the wetland were low compared to reference wetlands and contrary to my hypothesis, showed no relationship with the loading rate of added organic matter or total soil C. The addition of moderate amounts of organic matter (< 11.2 kg m-2) to the wetland did not greatly increase greenhouse gas emissions, while the addition of high amounts produced additional carbon dioxide, but not CH4.
I found that the static chambers I used for sampling CH4 in wetlands were highly sensitive to soil disturbance. Temporary compression around chambers during sampling inflated the initial chamber CH4 headspace concentration and/or lead to generation of nonlinear, unreliable flux estimates that had to be discarded. I tested an often-used rubber-gasket sealed static chamber against a water-filled-gutter seal chamber I designed that could be set up and sampled from a distance of 2 m with a remote rod sampling system to reduce soil disturbance. Compared to the conventional design, the remotely-sampled static chambers reduced the chance of detecting inflated initial CH4 concentrations from 66 to 6%, and nearly doubled the proportion of robust linear regressions from 45 to 86%. The new system I developed allows for more accurate and reliable CH4 sampling without costly boardwalk construction.
I explored the relationship between CH4 emissions and aquatic herbivores, which are recognized for imposing top-down control on the structure of wetland ecosystems. The biogeochemical consequences of herbivore-driven disruption of plant growth, and in turn, mediated oxygen transport into wetland sediments, were not previously known. Two growing seasons of herbivore exclusion experiments in a major waterfowl overwintering wetland in the Southeastern U.S. demonstrate that waterfowl herbivory had a strong impact on the oxygen-sensitive processes of CH4 emission and nitrification. Denudation by herbivorous birds increased cumulative CH4 flux by 233% (a mean of 63 g CH4 m-2 y-1) and inhibited coupled nitrification-denitrification, as indicated by nitrate availability and emissions of nitrous oxide. The recognition that large populations of aquatic herbivores may influence the capacity for wetlands to emit greenhouse gases and cycle nitrogen is particularly salient in the context of climate change and nutrient pollution mitigation goals. For example, our results suggest that annual emissions of 23 Gg of CH4 y-1 from ~55,000 ha of publicly owned waterfowl impoundments in the Southeastern U.S. could be tripled by overgrazing.
Hydrologically controlled moist-soil impoundment wetlands provide critical habitat for high densities of migratory bird populations, thus their potential to export nitrogen (N) to downstream waters may contribute to the eutrophication of aquatic ecosystems. To investigate the relative importance of N export from these built and managed habitats, I conducted a field study at an impoundment wetland that drains into hypereutrophic Lake Mattamuskeet. I found that prescribed hydrologic drawdowns of the impoundment exported roughly the same amount of N (14 to 22 kg ha-1) as adjacent fertilized agricultural fields (16 to 31 kg ha-1), and contributed approximately one-fifth of total N load (~45 Mg N y-1) to Lake Mattamuskeet. Ironically, the prescribed drawdown regime, designed to maximize waterfowl production in impoundments, may be exacerbating the degradation of habitat quality in the downstream lake. Few studies of wetland N dynamics have targeted impoundments managed to provide wildlife habitat, but a similar phenomenon may occur in some of the 36,000 ha of similarly-managed moist-soil impoundments on National Wildlife Refuges in the southeastern U.S. I suggest early drawdown as a potential method to mitigate impoundment N pollution and estimate it could reduce N export from our study impoundment by more than 70%.
In this dissertation research I found direct relationships between wetland restoration and impoundment management practices, and biogeochemical responses of greenhouse gas emission and nutrient cycling. Elevated soil C at a restored wetland increased CO2 losses even ten years after the organic matter was originally added and intensive herbivory impact on emergent aquatic vegetation resulted in a ~230% increase in CH4 emissions and impaired N cycling and removal. These findings have important implications for the basic understanding of the biogeochemical functioning of wetlands and practical importance for wetland restoration and impoundment management in the face of pressure to mitigate the environmental challenges of global warming and aquatic eutrophication.
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Major- and trace-element analyses, mineral chemistry, and Sr-Nd isotopic determinations were obtained on representative igneous rocks drilled from the Nankai accretionary complex (Site 808) during Ocean Drilling Program Leg 131. For the first time, the oceanic basement of the subducting plate below an accretionary prism has been reached. The Nankai Trough basement was encountered at a depth of 1289.9 mbsf and a total of 37.1 m of igneous rocks, middle Miocene (15.6 Ma) in age, was penetrated. Two main lithological units have been distinguished from the top downward; sill-like rocks (Unit I: Cores 105, 106, 107) and pillow lavas (Unit II: Core 108). Basalts are predominantly nonvesicular, hypocrystalline, aphyric to slightly phyric with intersertal to intergranular textures. Alteration is generally slight to moderate. All the basaltic rocks are cut by ramifying veins of varying widths. Secondary mineral assemblages (including vein fillings) are typical of submarine alteration and zeolite to low greenschist facies metamorphism. The order of crystallization of primary minerals is: olivine, plagioclase, clinopyroxene. This, together with mineral chemistry, characterized by forsteritic olivine (Fo 84-85), highly anorthitic Plagioclase (up to An 90), and in particular the composition of clinopyroxene, are typical of normal mid-ocean ridge basalts (MORB). In terms of Zr/Y (2.9-3.8) and Zr/Nb (21-58), all the analyzed samples plot in the normal MORB field. The chondrite-normalized REE patterns confirm the close affinity with normal MORB type (LaN/SmN: 0.6-0.8). Note that such magmatism does not reveal any evidence of subduction-related geochemical components. The 87Sr/86Sr isotopic ratios range from 0.70339 in pillow lavas to 0.70317 in the least-altered basalts of sill units (ratios reduced to 0.70265-0.70271 by HC1 2.5 N hot leaching), whereas 143Nd/144Nd ratios are 0.51314-0.51326. These values conform with those of normal MORB. Stratigraphy, petrography, and geochemistry of the basaltic rocks recovered at Site 808 appear very similar to those from the Shikoku Basin basement (particularly Sites 442 and 443, DSDP Leg 58), analogously identified as normal MORB.
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A high resolution marine pollen record from site GeoB1023, west of the northern Namib desert provides data on vegetation and climate change for the last 21 ka at an average resolution of 185 y. Pollen and spores are mainly delivered to the site by the Cunene river and by surface and mid-tropospheric wind systems. The main pollen source areas are located between 13°S and 21°S, which includes the northern Namib desert and semi-desert, the Angola-northern Namibian highland, and the north-western Kalahari. The pollen spectra reflect environmental changes in the region. The last glacial maximum (LGM) was characterised by colder and more arid conditions than at present, when a vegetation with temperate elements such as Asteroideae, Ericaceae, and Restionaceae grew north of 21°S. At 17.5 ka cal. B.P., an amelioration both in temperature and humidity terminated the LGM but, in the northern Kalahari, mean annual rainfall in the interval 17.5-14.4 ka cal. B.P. was probably 100-150 mm lower than at present (400-500 mm/y). The Late-glacial to early Holocene transition includes two arid periods, i.e. 14.4-12.5 and 10.9-9.3 ka cal. B.P. The last part of the former period may be correlated with the Younger Dryas. The warmest and most humid period in the Holocene occurred between 6.3 and 4.8 ka cal. B.P. During the last 2000 years, human impact, as reflected by indications of deforestation, enhanced burning and overgrazing, progressively intensified.
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Manganese deposits are abundant in various places in the Oshima Peninsula southwest of Hokkaido. This is particular the case of Todoroki Mine situated about 25 kilometers to the south-east of the Ginzan railway station in Siribesi Province. It consists of manganese beds intermixed with a tertiary volcanic tuff complex overlaying granite.
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El carácter innovador y feminista del mediometraje Margarita y el lobo (1969) supuso la censura total de la película y el ostracismo hacia su directora, la entonces estudiante de la EOC, Cecilia Bartolomé. En este artículo repasamos sus anteriores cortometrajes para desgranar los primeros matices de protesta así como la utilización de la expresión musical como vehículo del discurso feminista en Margarita y el lobo. A través de los planteamientos de la musicóloga Susan McClary que abordan sexualidad, género y feminismo concluimos con una visión del análisis de género en las obras musicales, al vincular sus estudios al film de Bartolomé. Del mismo modo, analizamos la función que cumple la música en el mediometraje. Para ello, examinamos el repertorio de canciones presente en Margarita y el lobo para terminar reconociendo la función discursiva y referencial como piezas claves en la película de la directora.
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Ageing of the population is a worldwide phenomenon. Numerous ICT-based solutions have been developed for elderly care but mainly connected to the physiological and nursing aspects in services for the elderly. Social work is a profession that should pay attention to the comprehensive wellbeing and social needs of the elderly. Many people experience loneliness and depression in their old age, either as a result of living alone or due to a lack of close family ties and reduced connections with their culture of origin, which results in an inability to participate actively in community activities (Singh & Misra, 2009). Participation in society would enhance the quality of life. With the development of information technology, the use of technology in social work practice has risen dramatically. The aim of this literature review is to map out the state of the art of knowledge about the usage of ICT in elderly care and to figure out research-based knowledge about the usability of ICT for the prevention of loneliness and social isolation of elderly people. The data for the current research comes from the core collection of the Web of Science and the data searching was performed using Boolean? The searching resulted in 216 published English articles. After going through the topics and abstracts, 34 articles were selected for the data analysis that is based on a multi approach framework. The analysis of the research approach is categorized according to some aspects of using ICT by older adults from the adoption of ICT to the impact of usage, and the social services for them. This literature review focused on the function of communication by excluding the applications that mainly relate to physical nursing. The results show that the so-called ‘digital divide’ still exists, but the older adults have the willingness to learn and utilise ICT in daily life, especially for communication. The data shows that the usage of ICT can prevent the loneliness and social isolation of older adults, and they are eager for technical support in using ICT. The results of data analysis on theoretical frames and concepts show that this research field applies different theoretical frames from various scientific fields, while a social work approach is lacking. However, a synergic frame of applied theories will be suggested from the perspective of social work.
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Las TIC son inseparables de la museografía in situ e imprescindibles en la museografía en red fija y móvil. En demasiados casos se han instalado prótesis tecnológicas para barnizar de modernidad el espacio cultural, olvidando que la tecnología debe estar al servicio de los contenidos de manera que resulte invisible y perfectamente imbricada con la museografía tradicional. Las interfaces móviles pueden fusionar museo in situ y en red y acompañar a las personas más allá del espacio físico. Esa fusión debe partir de una base de datos narrativa y abierta a obras materiales e inmateriales de otros museos de manera que no se trasladen las limitaciones del museo físico al virtual. En el museo in situ tienen sentido las instalaciones hipermedia inmersivas que faciliten experiencias culturales innovadoras. La interactividad (relaciones virtuales) debe convivir con la interacción (relaciones físicas y personales) y estar al servicio de todas las personas, partiendo de que todas, todos tenemos limitaciones. Trabajar interdisciplinarmente ayuda a comprender mejor el museo para ponerlo al servicio de las personas.
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The occurrence of hand grindstones at the Cogotas I archaeological sites is considered to be a common feature. Given that a distant-provenance raw material is frequently involved, determination of its source is a basic factor in the search for a better understanding of resource management and for any Political Economy approach. To progress in these directions an overall study should be planned, using selected grindstones with a view to covering diverse sub-zones of the Cogotas I dispersal area, especially because of its considerable distance from the granite basement source. Such a study may today includes diverse analytical procedures combining successive geographic, petrographic, mineralogical and geochemical criteria. To check the plausibility of the proposed methodology, a preliminary test has been carried out on two granite grindstones, obtained at the archaeological excavation at the Castronuño (Valladolid) Cogotian site, which is fifty km away from an inferred source area that was presumably located at Peñausende (Zamora). The result obtained validates the proposed operational process, yielding a generalizable knowledge to other similar situations.
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Jean-Luc Marion’s phenomenology of giveness constitutes one of the most outstanding attempts to set up a universal theory of the phenomenologically given as a whole within the framework of contemporary philosophical thought. The aim of the present study is to apply the main categories of this phenomenological theory concerning gift to the singular type of phenomenon represented by the pure indeterminate and anonymous being to which Emmanuel Levinas refers by the name of il y a (“there is”) in his early writings (and also subsequently). Therefore, this concerns examining the multiple specific modes of giveness proper to the impersonal “there is” and also its paradoxical relationship both with the donor and with the receiver of such gift in order to show the possibility of a “third way” of phenomenological investigation. This is a way equally distant from the western traditional concept of Being as “stable presence” and from Levinas’ proposal geared to substitute ontology for ethics as “first philosophy”.
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Copyright history has long been a subject of intense and contested enquiry. Historical narratives about the early development of copyright were first prominently mobilised in eighteenth century British legal discourse, during the so-called Battle of the Booksellers between Scottish and London publishers. The two landmark copyright decisions of that time – Millar v. Taylor (1769) and Donaldson v. Becket (1774) – continue to provoke debate today. The orthodox reading of Millar and Donaldson presents copyright as a natural proprietary right at common law inherent in authors. Revisionist accounts dispute that traditional analysis. These conflicting perspectives have, once again, become the subject of critical scrutiny with the publication of Copyright at Common Law in 1774 by Prof Tomas Gomez-Arostegui in 2014, in the Connecticut Law Review ((2014) 47 Conn. L. Rev. 1) and as a CREATe Working Paper (No. 2014/16, 3 November 2014).
Taking Prof Gomez-Arostegui’s extraordinary work in this area as a point of departure, Dr Elena Cooper and Professor Ronan Deazley (then both academics at CREATe) organised an event, held at the University of Glasgow on 26th and 27th March 2015, to consider the interplay between copyright history and contemporary copyright policy. Is Donaldson still relevant, and, if so, why? What justificatory goals are served by historical investigation, and what might be learned from the history of the history of copyright? Does the study of copyright history still have any currency within an evidence-based policy context that is increasingly preoccupied with economic impact analysis?
This paper provides a lasting record of these discussions, including an editorial introduction, written comments by each of the panelists and Prof. Gomez-Arostegui and an edited transcript of the Symposium debate.
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First published in 1897.
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Este artículo de investigación propone la aplicación de un modelo de gestión del conocimiento para mejorar el programa de capacitación en el Call Center de la empresa Promociones y Cobranzas Beta S.A., ubicada en la zona centro de Bogotá, Cra. 10 No. 16 -39 piso 13. La investigación se realizó durante el año 2015 utilizando como metodología revisión documental, entrevistas a los coordinadores del área y encuestas con un grupo de asesores del Call Center. La aplicación de dichas herramientas generó información acerca del proceso de capacitación actual. A partir de algunas teorías de gestión del conocimiento se buscó determinar el ciclo de las capacitaciones que mejor se adaptara a la necesidad del Call Center de Promociones y Cobranzas Beta S.A., de tal forma que la comunicación con los asesores de cobranzas fuera más efectiva y el conocimiento mantuviera una actualización permanente. La aplicación del modelo permitirá a la gerencia de la compañía, ampliar el conocimiento y mejorar en el servicio con los clientes atendidos, reflejando cumplimiento de las metas de cobro establecidas en el área. Palabras clave: Gestión del conocimiento, programa de capacitación, Call Center