1,574 research outputs found
Beyond the notion of performance anxiety: a phenomenological exploration of the lived experiences of anxiety for elite Egyptian tennis athletes
The purpose of this research is to gain a deeper understanding of the anxiety experiences of elite Egyptian tennis athletes before and during competition. This research proposes an alternative approach that offers a new insight into the notion of anxiety with athletes. It relates existential anxiety to athletes, using an Interpretative Phenomenological Approach to gain a more in-depth view of the phenomena of anxiety for these athletes. Eight elite Egyptian tennis athletes, 2 males and 6 females, between the ages of 18-25 were interviewed on their experiences of anxiety before and during competition. Four themes emerged from the transcript analysis including: the emotional and physical manifestations and sensations of anxiety, the meaning of competition for these athletes and how loss and identity are involved, the internal world of athletes with their expectations, over-thinking, selfconfidence and their routines, and the inter-relational world that involves how others influence these athletes’ anxiety and how being alone on the court is also part of their anxiety experience. These four themes reveal the complexity, multi-dimensionality and individuality of the anxiety experience for these athletes that opens up the rite de passage for incorporating counselling psychology using an existential approach to meet the existential needs of athletes. Its implications and recommendations for further research are also discussed to advocate integrating Existential psychology with Mental Skills Training to work with athletes as a whole being instead of only just a performer
Towards a clearer understanding of craving for alcohol
This thesis sought to gain a greater understanding of factors that motivate cravings for alcohol in problem drinkers. The research revealed that levels of mindfulness might play a crucial role in explaining how personality traits influence attentional processes and cravings underlying alcohol use
Polarized Localization Microscopy (plm) Detects Nanoscale Membrane Curvature And Induced Budding By Cholera Toxin Subunit B (ctxb)
The curvature of biological membranes at the nanometer scale is critically important for vesicle trafficking, organelle morphology, and disease propagation. Many proteins and lipids interact with diverse curvature sensing and curvature generating mechanisms. Deciphering the molecular mechanisms of toxin-membrane interactions has been limited by the resolution and drawbacks of conventional experimental techniques. This study reveals the inherent membrane bending capability of cholera toxin subunit B (CTxB) through the development and implementation of Polarized Localization Microscopy (PLM). PLM is a pointillist optical imaging technique for the detection of nanoscale membrane curvature in correlation with single-molecule dynamics and molecular sorting.
PLM combines polarized total internal reflection fluorescence microscopy and fluorescence localization microscopy to reveal membrane orientation without reducing localization precision by point spread function manipulation. Further, membrane curvature detection with PLM requires ≤19% of the localization density required with 3D fluorescence localization microscopy (e.g., PALM or STORM). Engineered hemispherical membrane curvature with varying radii of 24, 51, and 70 nm were detected with PLM while surrounded by planar supported lipid bilayers. Nanoscale membrane bud growth was spontaneously induced by CTxB on otherwise planar, quasi-one component lipid bilayers, revealing a mechanism of cholera immobilization and cellular internalization. The single lipid and single protein trajectories further quantified the effects of nanoscale membrane curvature and protein-lipid interactions. CTxB sorting to high membrane curvatures was detected and quantified.
Nanoscale membrane budding and tubulation was mainly driven by CTxB valency and structure. We demonstrated that varying either GM1 or CTxB concentrations on the membrane affects the budding structures. The number of crosslinked GM1s to a single CTxB affected the toxin behavior and mechanism on the membrane. Changing the lipid structure altered the bending mechanism and the eventual size and density of induced buds. Through future incorporation of single-particle tracking and live cells, PLM is poised to image the diverse molecular mechanisms that regulate nanoscale membrane bending
Magnetohydrodynamics in microchannels and adhesion properties of nanoporous alumina films
In the first part of this dissertation, RedOx-based magnetohydrodynamic (MHD) flows in three-dimensional (3D) microfluidic channels are investigated theoretically with a coupled mathematical model consisting of the Nernst-Planck equations for the concentrations of ionic species, the local electroneutrality condition of the electric potential, and the Navier-Stokes equations for the flow field. The induced currents and flow rates in 3D planar channels are compared with the experimental data obtained from the literature and those obtained from the previous two-dimensional mathematical model. Then a new approximate closed form solution for the velocity profile of steady incompressible MHD flows in a rectangular micro-channel is proposed. It can be used to optimize the dimensions of the channel and to determine the magnitudes and polarities of the prescribed currents in MHD networks so as to achieve the desired flow patterns and flow rates; In the second part of the dissertation, the adhesive properties of thin nanoporous alumina templates are investigated. Such templates are important in fabricating an array of nanopores that will be used in the Lab on a Chip technology
Entrepreneurship and the integration of refugees and migrants: A case study of Syrian refugees in Egypt
The Syrian Exodus is the biggest assemblage of refugees affecting not just neighboring countries of Jordan, Lebanon, Iraq, Egypt, and Turkey, comprising 95% of the Syrian refugees, but also European states, following refugees\u27 decisions to undertake the Death Journey by crossing the Mediterranean Sea (Pierini & Hackenbroich, 2015). Since the beginning of the Syrian conflict in 2011 the refugee crisis involves at least 11 million Syrians, from which 6.3 million are displaced and 13.5 million are in dire need of humanitarian assistance due to inexorable conditions (Mercy Corps, 2017) Protracted refugees situations take from five to twenty years. Numbers of Syrian refugees, who are hosted in Egypt, are ranging from 500,000 to two million, where only a fraction of them, 115,204, is registered (United Nations High Commissioner for Refugees (UNHCR) , 2017). Despite guarantees for individual considerations by the 1951 Convention and the 1967 Protocol, refugees are usually vulnerable, weary and aid dependent. At the same time, their individual contexts are neglected due to weak and fragmented policies enforcement, dwindling living conditions, legal restrictions and social and economic limitations for their livelihoods. Extant literature on refugees lacks a positive framing as enabling individuals and vital socio-economic and developmental tools. Shifting away from the traditional refugee warehousing approach, that denotes mobility restriction, idleness enforcement, aid dependency and incapacitated individuals, where their lives are put on hold in violation to the 1951 Refugee Convention law (Smith, 2006), and following successful case studies of refugees\u27 entrepreneurial tendencies, such as in Dadaab and Kakuma Camps in Kenya and Zaat\u27ari in Jordan. Entrepreneurship may serve as a source of innovation and a mean of income generation, carrying other non-monetary gains for sustainable livelihoods (Montclos & Kagwanja, 2000). To date, refugee entrepreneurship is a nascent research field that is distinct from ethnic entrepreneurship and migrant entrepreneurship. Among recent studies, Garba, Djafar, & Mansor (2013) and Chrysostome (2010) tackled different aspects for ethnic and migrant communities when they pursue entrepreneurial ventures. Considering that each context has a unique set of challenges, few researchers have attempted to understand the relationship between refugees\u27 entrepreneurial endeavors and their integration in hosting economies. Wauters & Lambrecht (2006) demonstrated qualitatively the entrepreneurship potential and analyzed associated socio-economic impacts of entrepreneurship among refugees in Belgium. In 2008, they assessed quantitatively their motivations and associated challenges (Wauters & Lambrecht, 2008). In another study by Mushaben (2006), it draws interesting findings that Turkish ethnic businesses bridged majority and minority cultures in German cities through their entrepreneurial efforts of Do-It-Yourself-Integration (DIY) processes. Consequently, participatory consciousness among males, and direct identification with the society for women resulted. Finally, within the third-generation of Turkish migrants, they start businesses outside the food sector and they are more likely to embrace the German citizenship (Mushaben, 2006). This research attempts to shed some light if entrepreneurial activities are enabling tools for integration in hosting communities. Following the administration of twelve in-depth interviews to Syrian refugees in Greater Cairo and by comparing empirical findings with literature, it proved that, as a consequence of disadvantages, that Syrians face in hosting communities, they pushed themselves to pursue entrepreneurship as a self-reliance strategy. Promoting factors of ethnic-cultural features, where Syrian businesspersons gain access to ethnic markets, labor and emotional support, enabled them to start first their offerings among their communities to enlarge their economic activities among members of hosting societies, by taking advantage of a common language, familiarity with the culture, and relative peace and stability. It is good to note that generalizations should be avoided in later research, especially when common factors of language proficiency and culture familiarity are missing. Additionally, without macroeconomic support of institutional bodies and policy makers, the sustainability of their economic work opportunities is at risk. Due to institutional voids, organizational and institutional barriers and lack of effective coordination among stakeholders, their political integration is set aside, at least for the short and medium terms. This research makes a theoretical contribution by stating that refugee entrepreneurship has common ethnic-cultural promoting factors as ethnic entrepreneurs with similar motives of necessity based migrant entrepreneurs of overcoming disadvantages they face in their daily routines. Their social links were necessary determinants for short-term acculturation through their informal economic activities that are illegal yet legitimate. Entrepreneurship among refugee communities cannot only rely on informal sources that are not replenished, as their economic sustainability and their political integration, as citizens in the hosting society, are both at risk. These findings have implications in better understanding of the dynamics behind refugees\u27 pursuit of economic opportunities; how they maintain them; if they can sustain their endeavors and what performance indicators are used to determine their success following their motivations. As practical implications, recommended solutions are suggested to formalize these interactions for local economies development and refugees empowerment
Skeletal and Dentofacial Features in Schoolchildren with Isolated Maxillary Lateral Incisor Agenesis (MLIA)
Purpose: The objective of this study is to investigate the characteristic skeletal and dentofacial morphological features of patients with isolated bilateral or unilateral congenital absence of maxillary lateral incisors in three dimensions through comparing them with non-hypodontia control group. Material and Methods: The sample of the study will be comprised of "63" school students, males and females within an age range (12–15) years, who had permanent dentition and affected by isolated bilateral or unilateral congenital absence of upper lateral incisors, excluding third molars, in order to measure some of traditionally used parameters and to be compared with non-hypodontia control sample. The significance test for the differences in dimensions between hypodontia and non-hypodontia subjects was performed using Student t-test. Results: Both of the angles ANB and the inclination of the occlusal plane to SN were significantly reduced in the patients compared with that of the controls; p < .05. The length of premaxilla in the MLIA group was shorter compared with that of the control group; p <.05. Moreover, this parameter was more noticeably reduced in the subjects of the bilateral agenesis subgroup (BMLIA) compared with those of the control sample; p < .05. Conclusions: This study concluded that the influence of MLIA appears exclusively in the 'external complex', which consists of: The anterior frontal part of the cranial base, ANS and premaxilla and the development of these parts decreases along with diminished upper lateral incisor-number
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