Variable Sweep Transition Flight Experiment (VSTFE): Unified Stability System (USS). Description and Users' Manual

NASA initiated the Variable Sweep Transition Flight Experiment (VSTFE) to establish a boundary layer transition database for laminar flow wing design. For this experiment, full-span upper surface gloves were fitted to a variable sweep F-14 aircraft. The development of an improved laminar boundary layer stability analysis system called the Unified Stability System (USS) is documented and results of its use on the VSTFE flight data are shown. The USS consists of eight computer codes. The theoretical background of the system is described, as is the input, output, and usage hints. The USS is capable of analyzing boundary layer stability over a wide range of disturbance frequencies and orientations, making it possible to use different philosophies in calculating the growth of disturbances on sweptwings

Group life insurance in Kuwait : problems and prospects

The Kuwaiti government obliged firms to cover part of employee's risks through legislation in 1965 and 1977. Employers should cover risks as death or job injury due to or during work. This had affected the group life insurance (GLI) market. The thesis examines the economics of this market. Problem of choosing the right life table with respect to Kuwaiti mortality rates is tested. The efficiency of using English life tables to estimate mortality rates in Kuwait GLI market is examined. The effects of GLI underwriters on the market are investigated. The Social Security Services (SSS) are offered for Kuwaitis only, Non-Kuwaitis face more economical insecurity than Kuwaitis do. Therefore, the demand for employees' group investment plan to cover future security facing Kuwaiti and non-Kuwaiti workers, in particular, is also considered. The thesis suggests several methods to solve the problems facing the Kuwait GLI market. Kuwaiti Mortality rates are estimated using data from both the Social Security Association (SSA) and a sample of term group life insurees to be compared with English and American life tables. Methods of avoiding lack of information, adverse selection, and moral hazard in Kuwait GLI market are proposed. Finally, the advantages of introducing group investment plan are examined, and it was shown that these could alleviate SSS problems. Use of group investment plan should reduce the cost of the SSS for Kuwaitis, secure part of Non-Kuwaitis risks, and assist insurers to avoid or reduce their economic problems

The role of institutional logics in shaping firm practices: the case of corporate governance and corporate social responsibility

This thesis investigates the role of institutional logics, as hidden drivers of firm behaviour, in shaping firm practices and decisions on corporate governance configurations and engagement in corporate social responsibility. It adopts a quantitative approach to identify and assess the embeddedness of family and market (non-family) logics in firm decision making, incorporating several behavioural dimensions in terms of real firm practices that are empirically proven to differ between family and non-family firms. The thesis builds on the socioemotional wealth preservation perspective regarding displaying family or non-family firm-like behaviour, and develops a new, institutional-based classification of firms, comprising family logic-driven and market logic-driven firms that draw from the notion of firm logic orientation – a latent explanatory, institutional factor. This institutional-based approach suggests a distinct view of the familiness and non-familiness, or marketness, of firms irrespective of ownership status (family or not). Particularly, this thesis emphasises that it is not family ownership status (or not), but the firm practices and behaviour that characterise and define firms in terms of their distinctive culture and nature. Using US-based data of firms listed on the S&P 1500 index in the period of 2006–2016, it tests the main and moderation effects of firm logic orientation through the empirical windows of corporate governance and corporate social responsibility. The analysis finds that family logic-driven firms differ from market logic-driven firms regarding the firm choice of internal corporate governance configurations and the magnitude of the established corporate governance determinant-configuration relationships. Specifically, relative to market logic-driven firms, family logic-driven firms appoint smaller and less independent boards and pay top managers lower total and equity-based compensation. Moreover, compared with the marketness logic orientation, the familiness of firms mitigates the effect of corporate governance determinants, including firm-specific, managerial and governance characteristics, on corporate governance configurations concerning the structure of the board of directors and the design of executive compensation. The findings also show that family logic-driven and market logic-driven firms vary in terms of the firm social performance of corporate social responsibility and the magnitude of the relationship between strategic conformity ¬– a legitimacy-seeking activity – and corporate social responsibility performance. Particularly, relative to market logic-driven firms, family logic-driven firms perform worse regarding firm engagement in corporate social responsibility. However, relative to the marketness logic orientation, the familiness of firms amplifies the social gains derived from firm legitimacy in relation to improving the perception of firms’ corporate social responsibility. This mitigates the otherwise negative impact of familiness logic orientation on corporate social responsibility performance. The findings indicate that, driving firm behaviour, the familiness logic orientation of firms presents a distinct, family-oriented business form that, apart from family ownership status (or not), differentiates firms from the standard, shareholder-oriented view of firms – so-called marketness logic orientation – in terms of firm practices and decisions. This implies that the latent institutional factor of firm logic orientation matters at least as much as the facet of ownership status for firm practices and behaviour. This thesis is one of the first to quantitatively measure the embeddedness of institutional logics – an intangible construct – in firm decision making based on the level of observed firm practices as a tangible manifestation of namely family and market logics, and to empirically examine the influence of family and market logics on firm practices and behaviour in the contexts of corporate governance and corporate social responsibility

Pre-clinical evaluation of advanced nerve guide conduits using a novel 3D in vitro testing model

Autografts are the current gold standard for large peripheral nerve defects in clinics despite the frequentlyoccurring side effects like donor site morbidity. Hollow nerve guidance conduits (NGC) are proposed alternatives toautografts, but failed to bridge gaps exceeding 3 cm in humans. Internal NGC guidance cues like microfibresare believed to enhance hollow NGCs by giving additional physical support for directed regeneration of Schwann cellsand axons. In this study, we report a new 3D in vitro model that allows the evaluation of different intraluminal fibrescaffolds inside a complete NGC. The performance of electrospun polycaprolactone (PCL) microfibres inside 5 mmlong polyethylene glycol (PEG) conduits were investigated in neuronal cell and dorsal root ganglion (DRG) cultures invitro. Z-stack confocal microscopy revealed the aligned orientation of neuronal cells along the fibres throughout thewhole NGC length and depth. The number of living cells in the centre of the scaffold was not significantly different tothe tissue culture plastic (TCP) control. For ex vivo analysis, DRGs were placed on top of fibre-filled NGCs to simulatethe proximal nerve stump. In 21 days of culture, Schwann cells and axons infiltrated the conduits along the microfibreswith 2.2 ± 0.37 mm and 2.1 ± 0.33 mm, respectively. We conclude that this in vitro model can help define internal NGCscaffolds in the future by comparing different fibre materials, composites and dimensions in one setup prior to animaltesting

The effect of aluminium nanocoating and water pH value on the wettability behavior of an aluminium surface

Experimental investigation was performed to highlight the influence of ionic bounding and surface roughness effects on the surface wettability. Nanocoating technique via e-beam physical vapor deposition process was used to fabricate aluminium (Al) film of 50, 100, and 150 nm on the surface of an Al substrate. Microstructures of the samples before and after deposition were observed using an atomic force microscopy. A goniometer device was later on used to examine the influence of surface topography on deionised water of pH 4, 7 and 9 droplets at a temperature ranging from 10 °C to 60 °C through their contact angles with the substrate surface, for both coated and uncoated samples. It was found that, although the coated layer has reduced the mean surface roughness of the sample from 10.7 nm to 4.23 nm, by filling part of the microstructure gaps with Al nanoparticles, the wettability is believed to be effected by the ionic bounds between the surface and the free anions in the fluid. As the deionised water of pH 4, and 9 gave an increase in the average contact angles with the increase of the coated layer thickness. On the other hand, the deionised water of pH 7 has showed a negative relation with the film thickness, where the contact angle reduced as the thickness of the coated layer was increased. The results from the aforementioned approach had showed that nanocoating can endorse the hydrophobicity (unwitting) nature of the surface when associated with free ions hosted by the liquid

A Comparative Interaction between Copper Ions with Alzheimer's β

The interaction of Cu2+ with the first 16 residues of the Alzheimer's amyliod β peptide, Aβ(1–16), and human serum albumin (HSA) were studied in vitro by isothermal titration calorimetry at pH 7.2 and 310 K in aqueous solution. The solvation parameters recovered from the extended solvation model indicate that HSA is involved in the transport of copper ion. Complexes between Aβ(1–16) and copper ions have been proposed to be an aberrant interaction in the development of Alzheimer's disease, where Cu2+ is involved in Aβ(1–16) aggregation. The indexes of stability indicate that HSA removed Cu2+ from Aβ(1–16), rapidly, decreased Cu-induced aggregation of Aβ(1–16), and reduced the toxicity of Aβ(1–16) + Cu2+ significantly

Relationship between the procoagulatory activity and the lung maturity in amniotic fluid

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