6,645 research outputs found
Remembering Democracy in the Debate over Election Reform
In FEC v. Wisconsin Right to Life, Inc., the United States Supreme Court held that the federal Bipartisan Campaign Reform Act violated the First Amendment right to free speech because the statute restricted a form of political speech known as issue advocacy. In attempting to protect this right from government intrusion, however, the Court improperly excluded considerations of democracy from its free speech analysis. The opinion consequently misrepresented the nature of the right to free speech for two independent but related reasons. First, because preserving a well-functioning democracy is the primary reason free speech is protected, the right to free speech does not exist when it is not justified by-nor when it conflicts with-the interest in preserving a healthy democracy. Second, an inductive review of American history and law shows that democracy is an independent right. The Court was therefore responsible for determining whether the political speech in question conflicted with the right to democracy and adjudicating between these two rights. By explicitly deciding not to weigh the impact that issue advocacy has on democracy, the Court set the dangerous precedent that courts can decide free speech cases without considering whether the speech in question tramples on the interests and rights that define it and determine its scope
Experimental tests on a pre-heated combustion chamber for ultra micro gas turbine device: air/fuel ratio evaluation
Current portable power generators are mainly based on internal combustion engine since they present higher values of efficiency comparing to other engines; the main reason why internal combustion engine is not convenient for micro power generation (5 - 30 kW) is because of their heaviness. Micro and ultra micro gas turbine devices, based on a micro compressor and a micro turbine installed on the same shaft, are more suitable for this scope for several reasons. Micro turbine systems have many advantages over reciprocating engine generators, such as higher power density (with respect to size and weight), extremely low emissions and few, or just one, moving part. Those designed with foil bearings and air-cooling operate without oil, coolants or other hazardous materials. Micro turbines also have the advantage of having the majority of their waste heat contained in their relatively high temperature exhaust. Micro turbines offer several potential advantages compared to other technologies for small-scale power generation, including: a small number of moving parts, compact size, lightweight, greater efficiency, lower emissions, lower electricity costs, and opportunities to utilize waste fuels. The object of this study is the experimental tests on a stand-alone gas turbine device with a pre-heated combustion chamber (CC), to validate the fuel consumption reduction, compared to an actual and commercial device, used on air models
Resilient hemp shiv aggregates with engineered hygroscopic properties for the building industry
This study focuses on the surface treatment of an extremely hydrophilic natural plant material, hemp shiv, using a functionalised silica based coating to provide hydrophobicity while retaining its moisture buffering ability. The chemical composition and physical structure of bio-based materials results in their extremely hydrophilic behaviour. In this work, a simple one step coating process was used to enhance the water-repellence of hemp shiv without compromising its ability to adsorb and release moisture. The coating modified the morphology and surface roughness of hemp shiv providing a hydrophobic surface having a water contact angle of 118° and reduced the bulk water absorption by 250% over 24 h. Mercury intrusion porosimetry (MIP) showed that the treatment refined the pore size distribution of hemp shiv, reducing the size of larger pores but not completely blocking the smaller pores thereby allowing hemp shiv to buffer moisture. Fourier-transform infrared spectroscopy (FTIR) revealed the chemical composition was modified by the coating, reducing the hydroxyl groups. Hemp shiv aggregates treated with functionalised silica based coating show potential for the development of robust lightweight building materials with enhanced hydrophobicity
Modification of hemp shiv properties using water-repellent solâgel coatings
For the first time, the hydrophilicity of hemp shiv was modified without the compromise of its hygroscopic properties. This research focused on the use of solâgel method in preparation of coatings on the natural plant material, hemp shiv, that has growing potential in the construction industry as a thermal insulator. The solâgel coatings were produced by cohydrolysis and polycondensation of tetraethyl orthosilicate (TEOS) using an acidic catalyst. Methyltriethoxysilane (MTES) was added as the hydrophobic precursor to provide water resistance to the bio-based material. Scanning electron microscopy (SEM) and focused ion beam (FIB) have been used to determine the morphological changes on the surface as well as within the hemp shiv. It was found that the solâgel coatings caused a reduction in water uptake but did not strongly influence the moisture sorption behaviour of hemp shiv. Fourier transformed infrared (FTIR) spectroscopy shows that the coating layer on hemp shiv acts a shield, thereby lowering peak intensity in the wavelength range 1200â1800 cmâ1. The solâgel coating affected pore size distribution and cumulative pore volume of the shiv resulting in tailored porosity. The overall porosity of shiv decreased with a refinement in diameter of the larger pores. Thermal analysis was performed using TGA and stability of coated and uncoated hemp shiv have been evaluated. Hemp shiv modified with solâgel coating can potentially develop sustainable heat insulating composites with better hygrothermal properties
Geometry and Construction of Ribbed Vaults: Choir of the Braga Cathedral
The study takes into account the choir vault of the Braga Cathedral as a paradigmatic example of the evolution process of Portuguese multi-ribbed vaults. In fact, it can be considered the first step of the features transmigration occurred throughout the Iberian Peninsula and evolved in a continuous transformation from building to building. The stylistic/typological interpretation, as it is often conducted, is not exhaustive for what concerns stone vaults: conception and meaning of subtended space, construction processes and methods of form definition are essential to read the structure. The study of late Gothic ribbed vaults fits into the research field of structural interpretation from the perspective of âform generatorsâ: this type of construction realizes a strict correspondence between the two aspects, materializing system stress lines through the rib. We analyze one of the first work attributed to Joao de Castilho. The cabeceira of the Braga Cathedral clearly shows traits inherited from ribbed vaults with petal flowers design, typical of Seville and Burgos areas. The various aspects that define the shape are mutually interpenetrating and inseparable: geometric definition, surfaces analysis, underlying spatiality and, finally, the way in which these three are connected to the constructive process. The possibilities of the ribbed lattices are achieved here by a sort of "sphericity research", as if to mediate Gothic reminiscences with the desire to absorb new Renaissance influences. The spatiality research is not an end in itself but can be considered, at the same time, result and assumption of precise constructive methods, giving rise to a logical sequence of steps connected to the building site economy
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Oral histories of the Nottinghamshire mental hospitals: exploring memories of giving and receiving care
The closure of the mental hospitals in the UK in the twentieth century has potentially obscured the relevance of psychiatric hospitals as therapeutic environments. The thesis explores the impact of closing the large-scale mental hospitals in the latter part of the twentieth century and the move to care in the community on service users and staff 30 years since their closure. This research has gathered the oral histories of older mental health service users who received care in Nottinghamâs mental hospitals and those of the staff that provided it in order to understand what has been lost through the modernisation of mental health services, where the relationships between staff and patients are typically short-term and veer towards crisis management. Participatory Action Research has informed the overall research involving participants in all stages of the research project in order to co-construct a history of giving and receiving care with former patients and staff in the now closed psychiatric hospitals in Nottinghamshire. The findings provide new insights into the value of inpatient care within psychiatric institutions and how it has been affected in the shift away from asylum care. Despite elements of social control within the mental hospitals reported by participants, the Nottingham mental hospitals were largely perceived as therapeutic environments, providing rich sources of social, emotional and practical support through the social networks that existed therein, including the social and spatial value of internal and external spaces in the provision of structured rehabilitation for recovery. Participants experienced a sense of dispossession with the advent of care in the community,which did away with the hospital communities that offered valuable occupation, structured social activities, refuge, asylum, and a place of belonging for many
EFFECTS OF IMPERVIOUSNESS ON FAMILY BIOTIC INDEX VALUES IN THE SOUTHERN APPALACHIAN HEADWATERS AND RESULTING EXTENSION EDUCATION
Clear, cool headwater streams in the mountains of North Carolina are inextricably linked to the surrounding landscape. Trickling perennial streams drain precipitation from their catchment and are capable of sustaining excellent water quality to support rich aquatic biodiversity that feeds and beneficially contributes to the stream network below. However, headwater ecosystems can be easily compromised by even seemingly insignificant anthropogenic impacts. Small headwater streams were not mapped until recently, and are now known to be ubiquitous. Although the NC Mountains contain some of the highest headwater streams densities in the nation, they remain very susceptible to changes in the catchments that sustain them. Understanding effects from changes in the catchment can ameliorate future impacts, prioritize preservation efforts and inform restoration trajectories. Although a variety of stakeholders have preserved and passively managed unimpaired stream systems, others have attempted to enhance or restore streams with limited success. Without consideration to the surrounding landscape, these efforts may not be successful. This dissertation offers a starting point for determining thresholds of anthropogenic impacts to sustain biological integrity in headwater streams and offers examples of successful Extension education outreach efforts
Leaving Neverland for Narnia: Childhood and Gender in Peter Pan, The Secret Garden, and The Lion, The Witch and The Wardrobe
British gender expectations are often epitomized in mature adults, either in society or within novels, but in Peter Pan, The Secret Garden, and The Lion, The Witch and The Wardrobe gender roles are interpreted by the child protagonists. J. M. Barrieâs Peter Pan inhabits the world of the Neverland, but the gender roles of Victorian England follow them from London to the home below the tree where Peter, Wendy, her brothers, and the Lost Boys reside in a pseudo-domestic sphere. Peter often engages in literal discussion of what it means to become an English man, while Wendy lives out a womanâs motherly responsibilities happily to perfection. Frances Hodgson Burnettâs The Secret Garden also engages with these Victorian roles in combination with the influence of the Romantic ideals of children, set up and furthered in the late 18th century to the Edwardian period. Her novel reveals the interplay between experiencing the best of Romantic ideals as a child and how those ideals come to influence affectively living out the eraâs domestic gender requirements as adults. C. S. Lewisâ The Lion, The Witch and The Wardrobe propels the conversation forward into the World Wars. Through a broadened sense of morality and nationalism, the childrenâs interplay with gender roles encompasses values more prominent in the British society of the wartime periods. Barrie, Burnett, and Lewisâ novels identify the gender roles expected of men and womenâs distinctly differing spheres in the times of Victorian to Wartime England through the application of these evolving concepts onto the boy and girl protagonists
Z â ÏÏ production at CMS
The first measurement of the Z â ÏÏ cross-section reconstructing hadronic and leptonic tau final states is presented. The data collected in 2010 with the CMS detector (CMS Collaboration, JINST 3 (2008) S08004) from p-p collisions at âs = 7TeV, corresponding to an integrated luminosity of about 36 pbâ1, are used. The cross section has been measured to be in good agreement with the
next-to-next-to-leading order electroweak prediction. The production of Z bosons decaying into tau pairs serves as an important benchmark for tau reconstruction and constitutes a reference Standard Model process for searches at the LHC, like the Minimal Supersymmetric Standard Model H â ÏÏ
Conservative non-surgical treatment of medication-related osteonecrosis of the jaws: a long-term prognostic evaluation
BACKGROUND: The conservative non-surgical treatment of medication-related osteonecrosis of the jaws (MRONJ) is generally advisable in patients with poor general health and/or a concomitant malignant disease as the priority is to control signs of infection and symptoms and to prevent a further bone disease progression.
AIMS: the aim of this study is to conduct an exploratory analysis on the long-term outcomes of the exclusive conservative non-surgical treatment on a big sample of MRONJ patients, all having a minimum follow-up of at least 12 months.
METHODS: A retrospective medical record review of patients diagnosed with MRONJ was carried out in three Oral Medicine /Oral Maxillofacial outpatients' departments. The conservative non-surgical treatment consisted of the use of local antiseptics with or without the use of antibiotics cycles. Regardless of stage, mobile fragments of bone were managed with non-surgical sequestrectomy. MRONJ lesions were staged according to both the American Association of Oral/Maxillofacial Surgeons staging system and the SICMF- SIPMO staging system. The primary outcome was the pain remission. Secondary outcomes were remission of signs of infection and complete clinical remission of MRONJ lesion.
RESULTS: One hundred and twenty-six patients were included in the study and observed for a mean time of 39.73 ± 27.38 months. About seventy-one percent of the sample was composed of oncologic patients. 51.1% of the MRONJ lesions had never experienced pain or relapses after the first pain remission, while in 46.8% relapses were successfully treated with medical therapy. Only in the 2.1% pain was persistent. 93% of the patients achieved either complete clinical healing of the lesions (32%), or a clinical stable disease (61%) experiencing pain and signs of infection remission. Only 7% of the patients were refractory to the non-surgical treatment and needed surgical interventions in order to achieve a better pain/infection control.
CONCLUSIONS: Although one third of the patients achieve complete clinical remission of MRONJ lesions, the non-surgical treatment had demonstrated to be effective in controlling pain and signs of infection in almost all the patients. Prospective multicenter, controlled trials are necessary to better determine the relative effectiveness of the non-surgical treatment for a more evidence-based approach to management of MRONJ
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