An analysis of personal problems of sophomore students

Thesis (M.A.)--Boston University, 1949. This item was digitized by the Internet Archive

Hypersonic vehicle simulation model: Winged-cone configuration

Aerodynamic, propulsion, and mass models for a generic, horizontal-takeoff, single-stage-to-orbit (SSTO) configuration are presented which are suitable for use in point mass as well as batch and real-time six degree-of-freedom simulations. The simulations can be used to investigate ascent performance issues and to allow research, refinement, and evaluation of integrated guidance/flight/propulsion/thermal control systems, design concepts, and methodologies for SSTO missions. Aerodynamic force and moment coefficients are given as functions of angle of attack, Mach number, and control surface deflections. The model data were estimated by using a subsonic/supersonic panel code and a hypersonic local surface inclination code. Thrust coefficient and engine specific impulse were estimated using a two-dimensional forebody, inlet, nozzle code and a one-dimensional combustor code and are given as functions of Mach number, dynamic pressure, and fuel equivalence ratio. Rigid-body mass moments of inertia and center of gravity location are functions of vehicle weight which is in turn a function of fuel flow

The impact of multiple sclerosis on the identity of mothers in Italy

Purpose: This paper reports on one of the themes that emerged from the analysis of the study, regarding the perceived influence of multiple sclerosis (MS) on the identity of mothers in the socio-cultural context of Italy. Method: In-depth interviews were conducted with 16 women at various stages of MS, with follow up interviews with seven of the women. Phenomenology guided the methodology and the analysis was conducted using interpretative phenomenological analysis. Results: Through the research the value of motherhood to the women who participated emerged. The findings illustrated how many strove to maintain controlof their MS, which led to some making comparisons of themselves and other mothers and feeling different. Some women described how they adjusted their roles and found strength in being mothers but others spoke of their feelings of loss. Most women described living in the moment, appreciating the present and living each day as it came. Another significant experience was fear of stigma, both realized in the form of “pity” from others, and the perceived and actual associated stigma for their families. This contributed to why some women were reluctant to disclose their condition. The mothers who took part in this study differed in how they perceived their disabled identity. Conclusion: Although this study was conducted in the socio-cultural setting of Italy, the findings have implications for professionals working with disabled mothers and women with MS in Italy and beyond; including recognizing the value associated with fully identifying oneself as a mother, rather than solely focusing on doingmothering tasks. • Implications for Rehabilitation • Professionals need to be mindful of the value of motherhood for women with multiple sclerosis. • Professionals should support women who feel like they are battling with maintaining control of their multiple sclerosis, who may be adjusting their identity as mothers; recognizing that they may be influenced by the stage of their multiple sclerosis and whether they were diagnosed before or after having their children. • Women can have feelings of loss related to their ability to fully participate in their children’s lives and professionals should work with women to help them identify the value of their mothering role not only in physically participating in activities but also in being emotionally and physically present as a mother

Spin-glass-like freezing of inner and outer surface layers in hollow γ-Fe2O3 nanoparticles

Disorder among surface spins is a dominant factor in the magnetic response of magnetic nanoparticle systems. In this work, we examine time-dependent magnetization in high-quality, monodisperse hollow maghemite nanoparticles (NPs) with a 14.8 ± 0.5 nm outer diameter and enhanced surface-to-volume ratio. The nanoparticle ensemble exhibits spin-glass-like signatures in dc magnetic aging and memory protocols and ac magnetic susceptibility. The dynamics of the system slow near 50 K, and become frozen on experimental time scales below 20 K. Remanence curves indicate the development of magnetic irreversibility concurrent with the freezing of the spin dynamics. A strong exchange-bias effect and its training behavior point to highly frustrated surface spins that rearrange much more slowly than interior spins. Monte Carlo simulations of a hollow particle corroborate strongly disordered surface layers with complex energy landscapes that underlie both glass-like dynamics and magnetic irreversibility. Calculated hysteresis loops reveal that magnetic behavior is not identical at the inner and outer surfaces, with spins at the outer surface layer of the 15 nm hollow particles exhibiting a higher degree of frustration. Our combined experimental and simulated results shed light on the origin of spin-glass-like phenomena and the important role played by the surface spins in magnetic hollow nanostructures

Exploring and developing student midwives' experiences (ESME) : an appreciative inquiry study

Background: There is increased focus on investing in midwifery students as our future workforce. Inquiring into what helps to support an enriched learning experience for student midwives in clinical placements is timely. Aim: To work collaboratively with key stakeholders (student midwives, midwives) in clinical placements to generate an experience-based understanding of what works well in relation to the student midwife experience and from this understanding, co-create ways to enhance students’ experiences. Design: An appreciative inquiry approach was used to discover what matters and what works well at present in the student midwife experience from the perspective of student midwives, midwives, and midwifery managers and to use this knowledge to create enhanced experiences in the future. Data were generated across four local health districts in New South Wales, Australia. Data were analysed using immersion crystallisation and then mapped to the ‘Senses Framework’. Setting: Four midwifery units in tertiary teaching public hospitals in NSW. Participants: There were 124 participants in this study: 45 midwifery students and 76 employed midwives. Measurements and findings: The data culminated in the refinement of the ‘Senses Framework’ for use in the midwifery learning context. Student midwives and midwives valued experiences that helped them to feel safe, to feel that they belong, to experience continuity in their learning and work, to have a sense of purpose, to have their achievements and their contributions to be recognised and to feel that they matter. Furthermore, the midwives themselves valued the experience of these senses in supporting them to be facilitators of learning in the workplace. The relational framework for learning together in the work-place has the potential to support achievement of the sense of security, belonging, continuity, purpose, achievement and significance for all involved. Key conclusions: There is much to celebrate in what is being achieved currently in promoting excellence in learning experiences in the midwifery context. In particular this study has made conscious the contribution that student midwives and midwives can and do make to enable the positive and reciprocal relationships that develop in the student midwife experience that support the nurturing of enriched learning environments. This study emphasised that learning in the workplace is a relational endeavour, rooted in the day to day engagement between student midwives, midwives and others. By mapping these positive processes to the senses framework these processes are made more explicit and provide guidance for enhancing the learning experience in the midwifery context. Implications for practice: The framework and related inquiry tools developed from the study may be useful in other settings to further test out the impact of this relational approach to learning for student midwives

An archaeal family-B DNA polymerase variant able to replicate past DNA damage: occurrence of replicative and translesion synthesis polymerases within the B family

A mutant of the high fidelity family-B DNA polymerase from the archaeon Thermococcus gorgonarius (Tgo-Pol), able to replicate past DNA lesions, is described. Gain of function requires replacement of the three amino acid loop region in the fingers domain of Tgo-Pol with a longer version, found naturally in eukaryotic Pol zeta (a family-B translesion synthesis polymerase). Inactivation of the 3'–5' proofreading exonuclease activity is also necessary. The resulting Tgo-Pol Z1 variant is proficient at initiating replication from base mismatches and can read through damaged bases, such as abasic sites and thymine photo-dimers. Tgo-Pol Z1 is also proficient at extending from primers that terminate opposite aberrant bases. The fidelity of Tgo-Pol Z1 is reduced, with amarked tendency tomake changes at G:C base pairs. Together, these results suggest that the loop region of the fingers domain may play a critical role in determining whether a family-B enzyme falls into the accurate genome-replicating category or is an errorprone translesion synthesis polymerase. Tgo-Pol Z1 may also be useful for amplification of damaged DNA