The purpose of this three-essay dissertation is to synthesize and extend the effects of decentralization in decision-making and supply chain complexity in the context of supply chain resilience (SCRES).First essay contributes to theory and practice by expanding resilience thinking into including supply chain orientation and organizational structure and their implications and also responds to prior research arguing for the importance of identifying organizational factors that improve supply chain resilience. Second essay contributes to the supply chain organizational structure and SCRES literature by not just providing empirical support for decentralization of decision making in times of disruptions but more precisely by showing the factors that either impede or facilitate decentralization at the organizational level. Understanding the interplay among these factors is critical to explaining the lack of success for decentralization in the context of SCRES. Third essay contributes to practice by reviewing some of the major complexity drivers present in the supply chains and providing strategies along with a four-step process that practitioners can use to manage complexity.

<p> Although nearly one third of the Canadian population is projected to be over the age of 65 by the year 2030, we know relatively little about how aging affects brain function generally, let alone how aging affects visual perception. The current dissertation was conducted as part of a research programme designed to better characterize how aging affects visual perception. </p> <p> Older persons exhibit a variety of deficits for perception of complex visual forms. The perception of these complex forms-including everyday forms such as faces and objects-is subserved by low-level channels that are selective, or tuned, for the orientation and spatial frequency of luminance-defined contours in the visual scene. The bandwidth of these channels is inversely related to the amount of information that they can pass on to higher visual processes; narrowly-tuned channels are better. Single-cell physiological investigations of primates suggest that visual cortex neurons thought to subserve these channels exhibit broader tuning in senescence. If these channels become broadly-tuned in older aging, this could explain age-related deficits for complex form perception. In Chapters 2 and 3 of the current thesis, I measured the tuning of these channels in otherwise healthy, older humans using psychophysical masking techniques. In Chapters 4 and 5, I measured the average tuning of the neurons thought to underlie these channels in older human adults, physiologically, using electroencephalography (EEG). Despite the aforementioned reports of functional decline in senescent neurons, psychophysical and physiological orientation and spatial frequency tuning did not differ between younger and older adults. One explanation for this discrepancy is that there is a methodological issue in the single-cell primate literature wherein anesthetics interact with senescence to produce seemingly broader neural tuning. Another explanation is that older humans do have otherwise detuned neurons and channels, but are able to tune their neurons and channels by the action of consciousness, attention, or age-related compensatory brain reorganization. </p> / Thesis / Doctor of Philosophy (PhD)

<p> An electrically conductive thermoplastic composite (ECTPC) consists of electrically conductive filler(s) at a concentration above percolation threshold distributed in an insulating polymer matrix. The high concentration of the filler required to achieve high electrical conductivity for ECTPC is usually accompanied with the deterioration of mechanical properties and a large increase in the viscosity which prevents feasible processing of these materials in common polymer processing equipments such as injection molding machinery. The initial focus of this work was to control these drawbacks by using combinations of conductive fillers namely carbon fiber (CF) and carbon black (CB) to create a hybrid-filler composite. Cyclic olefin copolymer (COC), an amorphous polyolefin, was used as the matrix material. It was found that carbon black and carbon fiber synergistically contribute to the transport of electrons through the matrix. The synergism exists at various filler concentrations including when one of the fillers was present below its percolation threshold, but not at high carbon fiber content. Results showed that where the concentration of CF was several fold higher than carbon black a good trade-off between viscosity and conductivity can be achieved so that the obtained composites can be reasonably processed tn common processing equipment e.g. in an injection molding machine </p> <p> Carbon fiber is preferred to carbon black as it leads to ECTPC with higher electrical conductivity and lower viscosity. However, the high aspect ratio fibers preferentially align in the flow direction leading to ECTPCs which have electrical conductivity several orders of magnitude greater in the in-plane rather than through-plane. We focused on foaming as a strategy to reorient the fibers toward the through-plane direction in foam injection molding. Through a fractional factorial experimental design, the effect of injection rate, melt temperature and mold temperature on electrical conductivity was screened at two levels for foam and nonfoam COC/CF(lO vol%)-CB(2 vol%) injection molded composites. It was found that foaming significantly enhanced the through-plane fiber orientation and through-plane conductivity of the hybrid composite at low injection rate and high melt temperature. The concurrence of the melt flow and bubble growth was considered to be the key mechanism for fiber reorientation while the cell size and shape should not disrupt the conductive path spanning the bulk of the material. </p> <p> The importance of the relative length scale of the fillers on cell size and subsequently, electrical conductivity was investigated by injection molding. Results showed that where the length scale of the filler was comparable to the cell size, as for foamed COC/CF composites, the conductivity considerably decreases with foaming. The drop was greater in the through plane direction and smaller in the in-plane direction for the composites with larger average fiber length. Also smaller cells led to a larger drop in the composite conductivity. It was observed that where the length scale of the filler was much smaller than the cell size as such for COC/CB composites, foaming enhanced the electrical conductivity particularly in the through-plane directions and its effects became more pronounced at lower carbon black concentrations. It was proposed that induced carbon black coagulation by foaming was the main reason for the observed improvement in conductivity. For COC/CF-CB hybrid composites, enhancement in through-plane conductivity, particularly at CB concentration below percolation, via foaming inferred that CB aggregates significantly contributed in improving fiber-fiber contacts. </p> <p> Reorientation of the fibers by foaming was found to be very dependent on processing conditions. High viscosity and fiber- fiber interactions can hinder fiber rotation. The general understanding of the investigation was that fiber reorientation may occur where the cells are much larger than the fibers. In comparison, a series of nonfoam injection molded composites containing CF, CB and CF-CB were foamed in a batch process to avoid flow effects. The insignificant change in fiber orientation with foaming proved that fibers can not rotate by the growth of an adjacent cell in the absence of shear. Also, a large drop in electrical conductivity with foaming as compared to the foam injection molded composites suggested that particle relocalization can not occur in batch foaming. </p> / Thesis / Doctor of Philosophy (PhD)

The domestic chick (Gallus gallus domesticus) has been widely used as an animal model to investigate spatial orientation and the neural mechanisms underlying this function. In all vertebrate species the hippocampus plays an essential role in spatial orientation. Since the hippocampus is a bilateral structure, it is important to investigate the specific role of the left and the right hippocampi in spatial processing. Although, the domestic chick has been often used as animal model to assess cognitive lateralization, the involvement of the left and the right hippocampal formation in spatial orientation has been poorly investigated in this model. Behavioral studies using monocular eye occlusion have shown that in chicks the left eye-system (right hemisphere) is involved in the elaboration of spatial relational information, while the right eye-system (left hemisphere) processes local information. However, while visual lateralization in chicks had been traditionally considered to be induced by embryonic light exposure, recent studies suggest the presence of structural and behavioural asymmetries also in dark-incubated chicks. Thus, the main aim of this thesis was to test the lateralization of hippocampal functions in dark incubated chicks, both in spatial and non-spatial tasks. In the first study dark-incubated chicks were trained to orient in a large circular arena using spatial relational information provided by free-standing objects. Once chicks reached a learning criterion they were tested binocularly or under a monocular eye-occlusion condition. This study provided the first demonstration that domestic chicks are able to orient by relational spatial information provided by free-standing objects, in binocular vision conditions. However, if either one of the two eyes was occluded, chicks failed the orientation task. These results show that at least in dark-incubated chicks binocular integration is needed to solve this spatial orientation task. We also investigated if chicks have a preference to orient by local or spatial information provided by free-standing objects and if this ability is influenced by eye occlusion. Chicks preferred to use local over spatial cues to orient, both in binocular and monocular conditions (independently of which eye was occluded). These results indicate that local cues are processed by both eye-systems and do not require access to information from both eyes, contrary to relational spatial cues. Using the same setup, in the second study we directly investigated the involvement of chicks’ left and right hippocampal formation during orientation by free-standing objects. For this purpose we performed an immunohistochemical staining of the immediate early gene product c-Fos (a neural activity marker). Two independent groups of dark-incubated chicks were trained to find food in the large circular arena and the level of hippocampal activation was compared between the two groups. One group was trained to orient exclusively by local cues, while the other was orienting by spatial relational information provided by free-standing objects. This revealed selective activation of the right hippocampus during orientation by spatial relational information in dark-incubated chicks. While monocular occlusion has often been used to test lateralization of spatial functions in chicks, it is still unclear whether this manipulation affects hippocampal activation. The aim of the third study was to clarify this issue, by exposing dark-incubated chicks to a novel environment in conditions of monocular occlusion or binocular vision. Activation of the hippocampal formation was once again measured by c-Fos expression. Exposure to a novel environment is known to trigger hippocampal activation in different animals, including domestic chicks. As expected, exposure to the novel environment activated the hippocampus in binocular vision conditions. However, if either one of the eyes was occluded, the hippocampal c-Fos expression did not rise above what observed in the baseline condition (chicks maintained in a familiar environment). Thus, successful hippocampal response to a novel environment requires input from both eyes. Our results also suggest that monocular occlusion equally affects the left and the right hippocampus. Overall, access to information from both eyes plays a crucial role for the acquisition of a spatial map of a novel environment, in line with the behavioral results of the first study. Moreover, a task independent lateralization effect, with higher c-Fos expression in the left compared to the right hippocampus, could be observed in all the experimental conditions. This confirms the presence of neuroanatomical lateralization in dark-incubated chicks. The last study investigated whether chicks’ hippocampus would also respond to novel social stimuli, in line with the activation observed in this structure after exposure to a novel environment. Only few studies have directly investigated the involvement of birds’ hippocampal formation in social functions. Here, the hippocampal activation was compared between chicks exposed to an unfamiliar conspecific vs. chicks exposed to a familiar one. We found that the ventral and dorsomedial portion of the right hippocampus of dark-incubated chicks responds to an unfamiliar individual. This provides the first demonstration of hippocampal sensitivity to social novelty in birds. Overall the studies performed in this thesis indicate a selective lateralized involvement of domestic chicks’ hippocampal formation not only in spatial, but also in social functions.

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The increasing demands of efficiency and effectiveness in the public sector encourage political leaders and policy makers to adopt and apply advanced techniques and solutions to overcome flaws in public organizational performance. Entrepreneurship was introduced in several Western countries as a way to improve their processes and management through adopting private sector management principles and market-oriented techniques. In 2015, Saudi Arabia announced its 2030 vision, which introduced hundreds of innovative and creative initiatives aiming to overcome issues of the turbulent environment, future oil depletion, budgetary pressures, and public demands for efficiency and effectiveness. Building on interdisciplinary perspectives, this study investigates entrepreneurial orientation among Saudi public employees from all administrative regions across the country. Building on McClelland's theory of motivation, this study hypothesizes that the motives of need for achievement, need for affiliation, and need for power are positively associated with entrepreneurial behavior. It also hypothesizes that excessive organizational hierarchy, formalization, and lack of autonomy constrain employees' entrepreneurial activities. Moreover, this study adopts a sociological perspective in proposing solutions for facilitating entrepreneurial orientation among public employees by hypothesizing that human and social capital promote an entrepreneurial orientation. Multiple regression analysis reveals that Saudi public employees with a higher level of need for achievement and need for power tend to be more entrepreneurial, while need for affiliation fails to predict entrepreneurial orientation. Furthermore, the findings suggest that a high level of hierarchy and formalization in public organizations is negatively associated to entrepreneurial orientation, while a high level of autonomy is positively associated with entrepreneurial orientation. Finally, the study finds that employees with a high level of breadth and depth of experience (human capital) are more likely to be entrepreneurial, while a high level of bonding social capital and bridging social capital promote a negative and a positive entrepreneurial orientation, respectively.

Carbon nanotubes are known as ideal fillers for polymer systems; the main advantage of carbon nanotubes over other nano-reinforcing particles is the combination of superior strength and stiffness with large aspect ratio. Carbon nanotubes may improve the mechanical, electrical and thermal properties of polymers, but to realise their potential in polymer systems uniform dispersion, strong interfacial adhesion and alignment of nanotubes within the polymer matrix are necessary. These properties are not easy to achieve and they are key challenges in producing CNT/Polymer system. This research was carried out in an attempt to understand how the properties of CNT/Polymer composite can be optimised by manipulation of additives, compounding and postcompounding conditions. Polypropylene/Multi-Walled Carbon Nanotube (PP/MCNT) composites were prepared by conventional twin screw extrusion. Dispersants and compatibilisers were used to establish good interaction between filler and polymer. Several different extruder screw configurations were designed and the properties of PP/MCNT composite prepared by each configuration investigated. The results indicated that the addition of carbon nanotubes without additives enhanced mechanical, electrical and thermal properties of polypropylene polymer. Incorporation of compatibilisers into PP/MCNT improved the stiffness but decreased the strength of the nanocomposite, whilst addition of dispersants decreased the mechanical properties of the nanocomposite. Addition of both additives at high concentration improved electrical conductivity and induced electrical percolation in the nanocomposite. Extruder screw configuration was found to have significant effect on the electrical conductivity whilst only slightly affecting mechanical properties of the nanocomposite, possibly due to the competition between dispersion and degradation of polymer chains and possible reduction of carbon nanotube length by intensive shear during compounding. The use of screw configuration with high mixing intensity promoted the dispersion of nanotubes and favoured the conduction process in the nanocomposite. Finally in an attempt to improve dispersion and alignment of carbon nanotubes, compounded PP/MCNT composite was subjected to micromoulding, fibre spinning and biaxial stretching processes and the resultant properties investigated. Application of post-compounding process was found to have significant effect on mechanical and rheological properties of the nanocomposite. Stiffness and strength of the nanocomposites treated by post-compounding processes were found to increase by up to 160% and 300%, respectively. The reinforcement effect of carbon nanotubes in the stretched nanocomposites was found to be the greatest. Rheological analysis suggested that the application of post-compounding processes enhanced dispersion of carbon nanotubes within the nanocomposite. Overall, this finding of this research has shown that carbon nanotubes can be incorporated into polypropylene using conventional equipment to provide significant improvement in properties. By careful choices of additives, compounding and postcompounding conditions, specific properties can be further enhanced. / Ministry of higher education in Kurdistan region in Iraq.

This study examined the relationships among psychological variables of sexual prejudice, psychological adjustment, and identity development. It was hypothesized that sexual orientation prejudice would be negatively related to psychological adjustment. It was further hypothesized that identity formation would moderate the relationship between sexual orientation prejudice and psychological adjustment. Participants were 200 college students, ages ranged from 18-48 (M = 21.96, SD = 4.87). Sexual orientation for the participants included self-identified labels of Heterosexual (88.5%), Homosexual (6.5%), Bisexual (3.5%), Pansexual (1%), and Demisexual (0.5%). Survey data were collected through a Psychology Research Experience website (SONA). Results revealed a negative correlation between Heterophobia, and Life Satisfaction. However, no statistically significant correlation was found between Homophobia and Life Satisfaction. Heterophobia (but not Homophobia) was significantly correlated with identity Exploration in Depth and Identification with Commitment. The measure of sexual adjustment revealed both Heterophobia and Homophobia positively correlated with Sexual Anxiety and Sexual Fear. The identity variables (Sexual Exploration and Sexual Commitment) were found to be related to sexual orientation prejudice. The moderator hypothesis was partially supported in that two moderator variables significantly interacted with sexual orientation prejudice (Heterophobia) and psychological adjustment (Sexual Anxiety and Sexual Fear). However, more research is needed to further elucidate the intricate relationships among psychological variables of sexual orientation prejudice, psychological adjustment, and identity development.

Homophobia plays a significant role in the treatment of individuals who identify as lesbian, gay, bisexual, or transgender (LGBT). The purpose of this study is to explore the presence of these types of negative attitudes as they present themselves in the nursing workforce. 520 registered nurses were contacted via email to partake in a survey assessing homophobic attitudes and perceptions regarding nursing care of LGBT persons. A total of 27 registered nurses responded and the resulting data were analyzed using descriptive statistics. A majority of registered nurses were female (89.3%), greater than 40 years of age (75%), white (75%), heterosexual (96.4%), and Christian (67.9%) with a Bachelor’s degree or less (57.1%). Homophobia scores averaged 27 on a scale from 12-60, higher scores translating to greater homophobia levels. This value is on the lower end of the scale, which interprets to lower levels of homophobia among the participants. While some of these scores did show the existence of negative attitudes toward LGBT individuals among participants, further investigation is needed with a larger, more representative sample. As a result, it is difficult to determine whether LGBT relations are improving with registered nurses.

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