Microwave heating of lunar materials. Appendix A

Microwave heating of nonmetallic inorganic material has been of interest for many years. Von Hippel in the late 1940's and early 1950's investigated how microwave radiation up to 10 GHz couples to various insulator materials. Perhaps the most work has been done by Wayne Tinga at the University of Edmonton. Most of the work to date has been done at the two frequency bands allowed in industrial use (0.915 GHz and 2.45 GHz). However some work has recently been carried out at 28 GHz and 60 GHz. Work done in this area at Los Alamos National Laboratory is discussed

New optical materials containing isobenzofuran

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Chemistry, 2009.Includes bibliographical references.Isobenzofuran, a member of the benzo[c]heterocycles, is an extremely reactive molecule with unusual electronic properties. In this thesis we investigate the integration of isobenzofuran subunits into conjugated optical materials. We discuss the properties of isobenzofuran, its role in organic chemistry, and the synthesis of isobenzofuran containing materials in the context of the other well known benzo[c]heterocycle, isothianaphthene. Isothianaphthene has been used in conducting polymers and organic fluorophores as a proquinoid unit, and we posit that isobenzofuran, due to its intrinsic instability, would display greater proquinoid character. To study this effect, we developed a synthetic route to integrate isobenzofuran into near-infrared donor-acceptor type fluorophores. These dyes, the IBF-NIADs, exhibit red-shifted absorption and emission over corresponding isothianaphthene containing dyes, thus highlighting the effective proquinoid nature of isobenzofuran. With the fundamentals of the IBF-NIAD dyes developed, we then expanded the series into a library of fluorophores for near-infrared fluorescence imaging application. Due to low absorption, autofluorescence, and scattering in the near-infrared region, near-infrared fluorescence imaging has the potential to provide non-invasive diagnostic techniques. In particular, our interest lay in imaging P-amyloid plaques, a hallmark pathology of Alzheimer's disease.(cont.) We tailored our dye series by modifying the conjugated backbone and the electron-donating group in order to optimize their photophysical properties, minimize their aggregation in aqueous solution, and maximize their optical response on binding to P-amyloid fibrils. Through these efforts we developed several fluorophores that exhibit large bathochromic shifts on binding, with concomitant increases in fluorescence intensity and lifetime, and absorption and emission spectra that extend well into the near-infrared. With the Backskai group at MGH, we found that most of these dyes stain P-amyloid plaques in transgenic APP/PS 1 mouse brain tissue, and efforts are underway to test their in vivo imaging potential. Finally, we present our initial synthetic work in integrating isobenzofuran into donor-acceptor-donor oligomers for nonlinear optical applications.by Scott Thomas Meek.Ph.D

Massively Expanded NEA Accessibility via Microwave-Sintered Aerobrakes

The availability of a wide range of natural resources among the near-Earth asteroid (NEA) population offers the opportunity to utilize these resources in the service of making access to most of the Solar System much easier than any classical approach which relies solely upon structural, heat-shield, life support and propellant materials lifted from Earth.We have concentrated our attention on the two main factors that influence the application and utility of in situ aerobrake manufacture on near-earth asteroids. The first of these is the use of microwave sintering in the fabrication of aerocapture heatshields for retrieval of asteroidal materials into Earth orbit; the second is assessment of the performance of these aerocapture devices, including making very large numbers of NEAs accessible as sources of essential materials to support space exploration and exploitation

Sex-Specific Heterosis in Line Crosses of Mice Selectively Bred for High Locomotor Activity

When populations with similar histories of directional selection are crossed, their offspring may differ in mean phenotype as compared with the average for the parental populations, often exhibiting enhancement of the mean phenotype (termed heterosis or hybrid vigor). We tested for heterosis in a cross of two replicate lines of mice selectively bred for high voluntary wheel running for 53 generations. Mice were paired to produce four sets of F1 offspring: two purebred High Runner (HR) lines and the hybrid reciprocal crosses. The purebred HR showed statistically significant, sex-dependent differences in body mass, wheel revolutions, running duration, mean running speed, and (controlling for body mass) organ masses (heart ventricles, liver, spleen, triceps surae muscle). Hybrid males ran significantly more revolutions than the purebred males, mainly via increased running speeds, but hybrid females ran intermediate distances, durations, and speeds, as compared with the purebred females. In both sexes, ventricles were relatively smaller in hybrids as compared with purebred HR. Overall, our results demonstrate differential and sex-specific responses to selection in the two HR lines tested, implying divergent genetic architectures underlying high voluntary exercise

Optical mapping of ground reaction force dynamics in freely behaving Drosophila melanogaster larvae

Funding: EPSRC (Doctoral Training grant EP/L505079/1 and grant EP/P030017/1), the European Research Council under the European Union’s Horizon 2020 Framework Programme (FP/2014-202) ERC grant agreement no. 640012 (ABLASE), and the Alexander von Humboldt Foundation via the Humboldt Professorship to MCGDuring locomotion, soft-bodied terrestrial animals solve complex control problems at substrate interfaces, but our understanding of how they achieve this without rigid components remains incomplete. Here, we develop new all-optical methods based on optical interference in a deformable substrate to measure ground reaction forces (GRFs) with micrometre and nanonewton precision in behaving Drosophila larvae. Combining this with a kinematic analysis of substrate-interfacing features, we shed new light onto the biomechanical control of larval locomotion. Crawling in larvae measuring ~1 mm in length involves an intricate pattern of cuticle sequestration and planting, producing GRFs of 1–7 µN. We show that larvae insert and expand denticulated, feet-like structures into substrates as they move, a process not previously observed in soft-bodied animals. These ‘protopodia’ form dynamic anchors to compensate counteracting forces. Our work provides a framework for future biomechanics research in soft-bodied animals and promises to inspire improved soft-robot design.Peer reviewe

Physical Education and Special Educational Needs in North-West England

The paper examines the inclusion of pupils with special educational needs (SEN) in mainstream secondary schools from the perspective of physical education (PE) teachers. The findings of this case study, which used individual interviews and was undertaken in the North-West of England, suggest that team games are activities which teachers find particularly difficult to plan and deliver in an inclusive way. Specifically, many teachers suggested that there was limited opportunity for individual planning during team games and that they found it difficult to develop and implement rules and adapt games to make them more inclusive. Moreover, there was an expressed feeling among teachers that, first, their initial teacher traininG (ITT) had not prepared them adequately for their day-to-day endeavours to include pupils with SEN in PE; and, second, that the schools in which they work are not providing them with any inclusion training. Finally, there was a general feeling among PE teachers that they are not receiving enough support from special educational needs coordinators (SENCOs) and learning support assistants (LSAs) whose role is, lest we forget, to enable teachers to include pupils with SEN in the mainstream education system

A novel approach to differentiate rat embryonic stem cells in vitro reveals a role for RNF12 in activation of X chromosome inactivation

textabstractX chromosome inactivation (XCI) is a mammalian specific, developmentally regulated process relying on several mechanisms including antisense transcription, non-coding RNA-mediated silencing, and recruitment of chromatin remodeling complexes. In vitro modeling of XCI, through differentiation of embryonic stem cells (ESCs), provides a powerful tool to study the dynamics of XCI, overcoming the need for embryos, and facilitating genetic modification of key regulatory players. However, to date, robust initiation of XCI in vitro has been mostly limited to mouse pluripotent stem cells. Here, we adapted existing protocols to establish a novel monolayer differentiation protocol for rat ESCs to study XCI. We show that differentiating rat ESCs properly downregulate pluripotency factor genes, and present female specific Xist RNA accumulation and silencing of X-linked genes. We also demonstrate that RNF12 seems to be an important player in regulation of initiation of XCI in rat, acting as an Xist activator. Our work provides the basis to investigate the mechanisms directing the XCI process in a model organism different from the mouse

The structural response of the cornea to changes in stromal hydration

The primary aim of this study was to quantify the relationship between corneal structure and hydration in humans and pigs. X-ray scattering data were collected from human and porcine corneas equilibrated with polyethylene glycol (PEG) to varying levels of hydration, to obtain measurements of collagen fibril diameter, interfibrillar spacing and intermolecular spacing. Both species showed a strong positive linear correlation between hydration and interfibrillar spacing2 and a non-linear, bi-phasic relationship between hydration and fibril diameter, whereby fibril diameter increased up to approximately physiological hydration, H = 3.0, with little change thereafter. Above H = 3.0, porcine corneas exhibited a larger fibril diameter than human corneas (p < 0.001). Intermolecular spacing also varied with hydration in a bi-phasic manner but reached a maximum value at a lower hydration (H = 1.5) than fibril diameter. Human corneas displayed a higher intermolecular spacing than porcine corneas at all hydrations (p < 0.0001). Human and porcine corneas required a similar PEG concentration to reach physiological hydration, suggesting that the total fixed charge that gives rise to the swelling pressure is the same. The difference in their structural responses to hydration can be explained by variations in molecular crosslinking and intra/interfibrillar water partitioning