Synthesis and characterization of poly[styrene-block-n-butyl methacrylate]

Thesis (B.S.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 1998.Includes bibliographical references (leaf 32).by Douglas J. Harris.B.S

Short chain fatty acid production from mycoprotein and mycoprotein fibre in an in vitro fermentation model

Dietary mycoprotein (marketed as QuornTM) has many health benefits, including reductions in energy intake. The majority of studies evaluating mycoprotein focus on the protein content and very few consider the fibre content. Fibre consumption is also associated with decreased energy intake, which is partly attributed to short chain fatty acids (SCFAs) from fibre fermentation by colonic bacteria. To study the SCFA-producing capability of mycoprotein, in vitro batch fermentations were conducted, and SCFA production compared with that from extracted mycoprotein fibre, oligofructose (OF), rhamnose, and laminarin. Mycoprotein and mycoprotein fibre were both fermentable, resulting in a total SCFA production of 24.9 (1.7) and 61.2 (15.7) mmol/L, respectively. OF led to a significantly higher proportion of acetate compared to all other substrates tested (92.6 (2.8)%, p < 0.01). Rhamnose generated the highest proportion of propionate (45.3 (2.0)%, p < 0.01), although mycoprotein and mycoprotein fibre yielded a higher proportion of propionate compared with OF and laminarin. Butyrate proportion was the highest with laminarin (28.0 (10.0)although mycoprotein fibre led to a significantly higher proportion than OF (p < 0.01). Mycoprotein is a valuable source of dietary protein, but its fibre content is also of interest. Further evaluation of the potential roles of the fibre content of mycoprotein is required

Black Hole Production at the Large Hadron Collider

Black hole production at the Large Hadron Collider (LHC) is an interesting consequence of TeV-scale gravity models. The predicted values, or lower limits, for the fundamental Planck scale and number of extra dimensions will depend directly on the accuracy of the black hole production cross-section. We give a range of lower limits on the fundamental Planck scale that could be obtained at LHC energies. In addition, we examine the effects of parton electric charge on black hole production using the trapped-surface approach of general relativity. Accounting for electric charge of the partons could reduce the black hole cross-section by one to four orders of magnitude at the LHC.Comment: CTP Symposium on Supersymmetry at LHC: Theoretical and Experimental Perspectives at the British University in Egypt 11-14 March 200

Black Hole Cross Section at the Large Hadron Collider

Black hole production at the Large Hadron Collider (LHC) was first discussed in 1999. Since then, much work has been performed in predicting the black hole cross section. In light of the start up of the LHC, it is now timely to review the state of these calculations. We review the uncertainties in estimating the black hole cross section in higher dimensions. One would like to make this estimate as precise as possible since the predicted values, or lower limits, obtain for the fundamental Planck scale and number of extra dimensions from experiments will depend directly on the accuracy of the cross section. Based on the current knowledge of the cross section, we give a range of lower limits on the fundamental Planck scale that could be obtained at LHC energies.Comment: 28 pages, 9 figures, LaTeX; added references, corrected typos, expanded discussio

The Application of Building Modifications and their Effects on Energy Consumption in Buildings

A huge amount of energy is used for air-conditioning in residential buildings in hot climates. Passive design features such as shading and advanced glazing can help to reduce energy use and carbon emissions, and thus mitigate the impact on climate change. This paper aimed at demonstrating how the application of selected modification devices such as solar films and shading devices affects the energy consumption patterns and levels in a residential building. A model of a building was constructed with VE using “Model IT” module, which was then analysed in a variety of different ways. A Virtual Integrated Environmental Solutions (IES-VE) was used to assess the energy gain and consumption parameters such as solar gains, shading devices, solar cloud and chilli clouds in residential buildings in Tripoli, Libya. The findings indicate that the best way to control and reduce the energy gains pattern in a building is to introduce energy modification devices such as shading device, solar films, emissivity paints and roof slab absorbers among others. In specific terms, the best device would be the application of external solar film, follow by shading device and internal solar film. An application of emissivity paints and roof slab absorbers does not contribute significantly to the energy reduction in the building. The study concludes that the application of modification devices in buildings can reduces the heat gain significantly. This study underscores the need and importance of the applications of energy modification devices in buildings in order to reduce their energy gains in the context of tropical regions. Though the climatological characteristics of tropical regions are similar, the generalisation of the findings in this study requires caution since the findings are limited in geographical context. Future research should also explore the impact of urban forms, street layout and orientation on solar penetration and energy use in buildings. Keywords: Architecture, Buildings, Climate change, Energy consumption, Energy gains, Liby

Microcanonical treatment of black hole decay at the Large Hadron Collider

This study of corrections to the canonical picture of black hole decay in large extra dimensions examines the effects of back-reaction corrected and microcanonical emission at the LHC. We provide statistical interpretations of the different multiparticle number densities in terms of black hole decay to standard model particles. Provided new heavy particles of mass near the fundamental Planck scale are not discovered, differences between these corrections and thermal decay will be insignificant at the LHC.Comment: small additions and clarifications, format for J. Phys.

Moral enhancement: do means matter morally?

One of the reasons why moral enhancement may be controversial, is because the advantages of moral enhancement may fall upon society rather than on those who are enhanced. If directed at individuals with certain counter-moral traits it may have direct societal benefits by lowering immoral behavior and increasing public safety, but it is not directly clear if this also benefits the individual in question. In this paper, we will discuss what we consider to be moral enhancement, how different means may be used to achieve it and whether the means we employ to reach moral enhancement matter morally. Are certain means to achieve moral enhancement wrong in themselves? Are certain means to achieve moral enhancement better than others, and if so, why? More specifically, we will investigate whether the difference between direct and indirect moral enhancement matters morally. Is it the case that indirect means are morally preferable to direct means of moral enhancement and can we indeed pinpoint relevant intrinsic, moral differences between both? We argue that the distinction between direct and indirect means is indeed morally relevant, but only insofar as it tracks an underlying distinction between active and passive interventions. Although passive interventions can be ethical provided specific safeguards are put in place, these interventions exhibit a greater potential to compromise autonomy and disrupt identity

Evaluation of First-Order Actuator Dynamics and Linear Controller for a Bio-Inspired Rotating Empennage Fighter Aircraft

This paper considers the problem of stabilizing a bio-inspired fighter aircraft variant at its Air Combat Maneuver Condition. The aircraft equations of motion are linearized, and an infinite-horizon linear quadratic regulator design is conducted for this aircraft. Included in the dynamics are first-order actuator models, which have the effect of slowing actuator responses. This is particularly important for the bio-inspired variant because it requires rotation of the empennage, which has relatively large inertia. The bio-inspired variant open-loop system is unstable in the short period and Dutch roll modes, which is mitigated in the closed-loop system. Monte Carlo simulation responses to initial condition dispersions, aerodynamic model errors, and atmospheric turbulence are presented for the controlled aircraft system. These simulations demonstrate the robust properties of the presented control design. Discussion is dedicated to control designs neglecting input from throttle and the rotating tail, and corresponding successes. Whereas the bio-inspired variant aircraft can be successfully controlled without rotating tail input, effects from neglecting throttle input show throttle should be included, but perhaps in an alternate loop such as a speed controller

Vertebrate Hosts as Islands: Dynamics of Selection, Immigration, Loss, Persistence, and Potential Function of Bacteria on Salamander Skin.

Skin bacterial communities can protect amphibians from a fungal pathogen; however, little is known about how these communities are maintained. We used a neutral model of community ecology to identify bacteria that are maintained on salamanders by selection or by dispersal from a bacterial reservoir (soil) and ecological drift. We found that 75% (9/12) of bacteria that were consistent with positive selection, <1% of bacteria that were consistent with random dispersal and none of the bacteria that were consistent under negative selection had a 97% or greater match to antifungal isolates. Additionally we performed an experiment where salamanders were either provided or denied a bacterial reservoir and estimated immigration and loss (emigration and local extinction) rates of bacteria on salamanders in both treatments. Loss was strongly related to bacterial richness, suggesting competition is important for structuring the community. Bacteria closely related to antifungal isolates were more likely to persist on salamanders with or without a bacterial reservoir, suggesting they had a competitive advantage. Furthermore, over-represented and under-represented operational taxonomic units (OTUs) had similar persistence on salamanders when a bacterial reservoir was present. However, under-represented OTUs were less likely to persist in the absence of a bacterial reservoir, suggesting that the over-represented and under-represented bacteria were selected against or for on salamanders through time. Our findings from the neutral model, migration and persistence analyses show that bacteria that exhibit a high similarity to antifungal isolates persist on salamanders, which likely protect hosts against pathogens and improve fitness. This research is one of the first to apply ecological theory to investigate assembly of host associated-bacterial communities, which can provide insights for probiotic bioaugmentation as a conservation strategy against disease