Optically-stimulated luminescence profiling and dating of historic agricultural terraces in Catalonia (Spain)

Dating agricultural terraces is a notoriously difficult problem for archaeologists. The frequent occurrence of residual material in terrace soils and the potential for post-depositional disturbance mean that conventional artefactual and lab-based dating methods often provide unreliable dates. In this paper we present a new technique using luminescence field profiling coupled with OSL dating to produce complete (relative) sequences of dates for sedimentary stratigraphies associated with agricultural terraces and earthworks. The method is demonstrated through a series of case-studies in western Catalonia, Spain, in which we reconstruct the formation sequence of earthwork features from the Middle Ages through to the present day. OSL profiling at the time of archaeological survey and excavation permitted spatially and temporally resolved sediment ‘chronologies’ to be generated, and provides the means to interpret the environmental and cultural archives contained in each. The case-studies presented here show that luminescence approaches are a valuable tool to reconstruct landscape histories

Composition variation and underdamped mechanics near membrane proteins and coats

We study the effect of membrane proteins on the shape, composition and thermodynamic stability of the surrounding membrane. When the coupling between membrane composition and curvature is strong enough the nearby composition and shape both undergo a transition from over-damped to under-damped spatial variation, well before the membrane becomes unstable in the bulk. This transition is associated with a change in the sign of the thermodynamic energy and hence has the unusual features that it can favour the early stages of coat assembly necessary for vesiculation (budding), while suppressing the activity of mechanosensitive membrane channels and transporters. Our results also suggest an approach to obtain physical parameters that are otherwise difficult to measure

Recycling controls membrane domains

We study the coarsening of strongly microphase separated membrane domains in the presence of recycling of material. We study the dynamics of the domain size distribution under both scale-free and size-dependent recycling. Closed form solutions to the steady state distributions and its associated central moments are obtained in both cases. Moreover, for the size-independent case, the~time evolution of the moments is analytically calculated, which provide us with exact results for their corresponding relaxation times. Since these moments and relaxation times are measurable quantities, the biophysically significant free parameters in our model may be determined by comparison with experimental data.Comment: 5 pages, 4 figure

Archaeological test pit excavations at Shillington, Bedfordshire

This report presents the results of a programme of archaeological excavation of 23 1m2 ‘test pits’ in the Bedfordshire village of Shillington carried out in summer 2013. The programme was funded by the Heritage Lottery Fund (HLF) through its ‘All Our Stories’ programme and supported by the Arts and Humanities Research Council (AHRC) Connected Communities theme which funded the Cambridge Community Heritage programme at the University of Cambridge in 20012-13. Over three days, more than 300 residents of the village of Shillington and the local area took part in the excavations in 23 different locations throughout the present village. The results provided new evidence for the development of the area now occupied by the village, which mostly lies alongside a small stream, from the prehistoric period onwards. The landscape was used by humans in the prehistoric period, apparently favouring the area nearer the small brook running west of the prominent hill which dominates the land around the parish. One test pit near this stream produced convincing evidence for undisturbed settlement remains in the immediate vicinity. Small quantities of pottery of Roman date came from five different sites, two of them away from the Brookside area hinting at a pattern of settlement or agricultural land use moving beyond the lower lying zones. No evidence was found for any activity dating to the period between the 5 th – 9 th centuries AD, but Saxo-Norman pottery of 10th – 11th century date was found in two distinct concentrations, suggesting more than one hamlet present, possibly part of a nucleated pattern of settlement, at this time. The high medieval period saw settlement at these sites grow and that at three other ‘ends’ appear, indicating a pattern of mixed dispersed and nucleated settlement. This growth ceases in the late medieval period, with Shillington particularly badly affected in this period of widespread demographic and settlement contraction compared to many settlements in the eastern region. In the postmedieval period, however, the test pit data indicates that Shillington gradually recovered, with former dispersed settlements mostly reoccupied, although it did not achieve its pre-14th century levels and some of the medieval ‘ends’ remained uninhabited until the 19th century

Model for Interdisciplinary Collaboration in Packaging Design

This paper explores a studio course in packaging design within Rochester Institute of Technology, which touches on three key elements: First, the course is designed as an interdisciplinary studio comprised of fourth year and graduate students in graphic design, industrial design and packaging science, allowing them to refine skills in their own disciplines while expanding their breadth in other methods of thinking. This model, commonly called “T-shape” profile, is crucial in today’s professional practice (Design Council 2006). Second, the course involves a Fortune 500 company sponsor, who challenges students to develop packaging solutions in an internal design competition. While collaborations between academia and industry have been common since the Nineteenth Century, they never cease to offer great benefits to all parties involved (Lee 2000, 111). Third, the course assignments require students to develop environmentally friendly solutions. Sustainability has become a key element in packaging design, given the negative effect that current practices in manufacturing and mass consumption have on the environment (Elshof 2008, 134)

High Temporal Resolution XMM Monitoring of PKS 2155-304

The bright, strongly variable BL Lac object PKS 2155-304 was observed by XMM for two essentially uninterrupted periods of ~11 and 16 hr on 30-31 May 2000. The strongest variations occurred in the highest energy bands. After scaling for this effect, the three softest bands (0.1-1.7 keV) showed strong correlation with no measurable lag to reliable limits of \tau \ls 0.3 hr. However, the hardest band (~3 keV) was less well-correlated with the other three, especially on short time scales, showing deviations of ~10-20% in ~1 hr although, again, no significant interband lag was detected. This result and examination of previous ASCA and BeppoSAX cross-correlation functions suggest that previous claims of soft lags on time scales of 0.3-4 hr could well be an artifact of periodic interruptions due to Earth-occultation every 1.6 hr. Previous determinations of the magnetic field/bulk Lorentz factor were therefore premature, as these data provide only a lower limit of B \gamma^{1/3} \gs 2.5 G. The hardest band encompasses the spectral region above the high-energy break; its enhanced variability could be indicating that the break energy of the synchrotron spectrum, and therefore of the underlying electron energy distribution, changes independently of the lower energies.Comment: 13 pages, 3 figures, accepted by Ap