Deleterious consequences of antioxidant supplementation on lifespan in a wild-derived mammal

Peer reviewedPublisher PD

Five year prognosis in patients with angina identified in primary care : incident cohort study

Peer reviewedPublisher PD

The Utilisation and Exploitation of Plants at Norse Age Sites in the North of Scotland: A Study Embracing Sites in Caithness, Orkney and Shetland

In this thesis, I will examine the utilisation and exploitation of cultivated and wild plants with particular reference to the subsistence economies and to the material culture in Caithness, Orkney and Shetland (Fig 1) during the Norse Period. In doing so, I would seek to present a case to suggest that in many instances it is possible that cultivated plants, other than just cereals, together with wild plant species were exploited intentionally as an important food, culinary, medicinal and material resource in the domestic economy. The opportunity will be taken in Chapter 1 to look at the geology, soils and climatic information that is available. Consideration will also be given to the various pollen analytical investigations which have been published and which will provide an insight into the past ecology of these land masses. All this information will help to provide a picture of the past environment, the available plant resources and the conditions for plant production. In Chapter 2 a range of written sources will include reference to the Orkneyinga Saga and will also take account of the available information that can be derived from the study of place-names and their distribution. A wealth of ethnohistorical information will be taken account of in Chapter 3, with particular attention to the traditional lifestyle of the past communities living in the Northern latitudes. This information will allow, to a great extent, the reconstruction of earlier times to be made. The role of Chapter 4 will be to briefly present details of the archaeological excavations at the sites that have been included in this study; and to provide the detailed evidence from the sites of the I domestic economies with particular reference to the crop plants and other plant remains that have been identified to date. In Chapter 5 an analysis will be undertaken of the available evidence of both cultivated and wild plant resources with a view to assessing their role and importance in the economic strategies and sociopolitical needs of the Norse communities. Past recorded uses will be taken into account in proposing the potential uses of many of the plant specites discovered on the sites. Particular attention will be given to relating such information to the dietary/medicinal needs as well as the potential craft and industrial uses. The means by which plant material came to be carbonized will also be considered, and the likely availability and sources of tree species will be taken account of. The intention of Chapter 6 will be to consider and compare the evidence of plant remains from other sites of comparable age in Britain, Ireland and Scandinavia, with particular attention to faecal deposits. Such undisputed evidence of dietary food sources will provide a useful comparison of plant species being consumed on these sites with those found on the sites within the study area. In the final. Chapter 7, it is proposed to outline the main conclusions of the study and to indicate possible areas of future research

Secretory vesicles are preferentially targeted to areas of low molecular SNARE density

Intercellular communication is commonly mediated by the regulated fusion, or exocytosis, of vesicles with the cell surface. SNARE (soluble N-ethymaleimide sensitive factor attachment protein receptor) proteins are the catalytic core of the secretory machinery, driving vesicle and plasma membrane merger. Plasma membrane SNAREs (tSNAREs) are proposed to reside in dense clusters containing many molecules, thus providing a concentrated reservoir to promote membrane fusion. However, biophysical experiments suggest that a small number of SNAREs are sufficient to drive a single fusion event. Here we show, using molecular imaging, that the majority of tSNARE molecules are spatially separated from secretory vesicles. Furthermore, the motilities of the individual tSNAREs are constrained in membrane micro-domains, maintaining a non-random molecular distribution and limiting the maximum number of molecules encountered by secretory vesicles. Together our results provide a new model for the molecular mechanism of regulated exocytosis and demonstrate the exquisite organization of the plasma membrane at the level of individual molecular machines

Total Water Content Measurements with an Isokinetic Sampling Probe

The NASA Glenn Research Center has developed a Total Water Content (TWC) Isokinetic Sampling Probe. Since it is not sensitive to cloud water particle phase nor size, it is particularly attractive to support super-cooled large droplet and high ice water content aircraft icing studies. The instrument is comprised of the Sampling Probe, Sample Flow Control, and Water Vapor Measurement subsystems. Analysis and testing have been conducted on the subsystems to ensure their proper function and accuracy. End-to-end bench testing has also been conducted to ensure the reliability of the entire instrument system. A Stokes Number based collection efficiency correction was developed to correct for probe thickness effects. The authors further discuss the need to ensure that no condensation occurs within the instrument plumbing. Instrument measurements compared to facility calibrations from testing in the NASA Glenn Icing Research Tunnel are presented and discussed. There appears to be liquid water content and droplet size effects in the differences between the two measurement techniques

Convection in a mushy-layer along a heated wall

Motivated by the mushy zones of sea ice, volcanoes, and icy moons of the outer solar system, we perform a theoretical and numerical study of boundary-layer convection along a vertical heated wall in a bounded ideal mushy region. The mush is comprised of a porous and reactive binary alloy with a mixture of saline liquid in a solid matrix, and is studied in the near-eutectic approximation. Here we demonstrate the existence of four regions and study their behavior asymptotically. Starting from the bottom of the wall, the four regions are (i) an isotropic corner region; (ii) a buoyancy dominated vertical boundary layer; (iii) an isotropic connection region; and (iv) a horizontal boundary layer at the top boundary with strong gradients of pressure and buoyancy. Scalings from numerical simulations are consistent with the theoretical predictions. Close to the heated wall, the convection in the mushy layer is similar to a rising buoyant plume abruptly stopped at the top, leading to increased pressure and temperature in the upper region, whose impact is discussed as an efficient melting mechanism

The Role of Emotional Overcontrol in Acceptance of Counselor Training Feedback

Effective feedback is a critical component of counselor training. The degree to which a recipient is able or willing to accept feedback can impact learning and skill development significantly. Recognizing individual trait differences can help the field of counseling understand feedback receptivity in counseling students. This study examined the possible relationship between feedback receptivity and the individual trait of emotional overcontrol. Results indicate that overcontrol accounted for variance in scores on a measure of feedback receptivity in a sample of counseling students, suggesting that individual trait differences meaningfully affect feedback receptivity

Optical Field Encryption for secure transmission of data

ABSTRACT The growing awareness of the vulnerability of information transmitted on communication systems within the government, military and commercial sectors, has stimulated a number of areas of research within the optical community to design optical hardware encryption systems providing inherent immunity to espionage techniques. This paper describes a hardware optical encryption technique that utilises off the shelf telecommunication equipment and negates the necessity for an independent key distribution system with respect to the data transmission system, as is common with alternative encryption system implementations. This method also lends itself easily to fiber optic or free space communication and is applicable within any optical waveband. The encryption-decryption of the optical signal is achieved through low coherence optical interferometry. This requires the instantaneous processing and analysis of the signal, optically, to retrieve the relevant optical phase information hidden in the transmitted optical noise. This technology allows an authorised user to transmit encrypted information at a high data rate securely, while maintaining opaqueness to an unauthorised observer that data transmission is occurring. As the instantaneous optical field properties of the signals present in the system are essential to the optical encryption -decryption process, the system is inherently protected against electronic recording and advances in computational decryption algorithms. For organisations wishing to protect sensitive data and levels of communication activity these are highly desirable features