All quiet on the neuronal front: NMDA receptor inhibition by prion protein

The normal function of the prion protein (PrP)—the causative agent of mad cow or prion disease—has long remained out of reach. Deciphering PrP's function may help to unravel the complex chain of events triggered by PrP misfolding during prion disease. In this issue of the JCB, an exciting paper (Khosravani, H., Y. Zhang, S. Tsutsui, S. Hameed, C. Altier, J. Hamid, L. Chen, M. Villemaire, Z. Ali, F.R. Jirik, and G.W. Zamponi. 2008. J. Cell Biol. 181:551–565) connects diverse observations regarding PrP into a coherent framework whereby PrP dampens the activity of an N-methyl-D-aspartate (NMDA) receptor (NMDAR) subtype and reduces excitotoxic lesions. The findings of this study suggest that understanding the normal function of proteins associated with neurodegenerative disease may elucidate the molecular pathogenesis

The effect of school resources on pupil attainment: a multilevel simultaneous equation modelling approach

Improving educational achievement in UK schools is a priority, and of particular concern is the low achievement of specific groups, such as those from lower socio-economic backgrounds. An obvious question is whether we should be improving the outcomes of these students by spending more on their education. The literature on the effect of educational spending on pupil achievement has a number of methodological difficulties, in particular the endogeneity of school resource levels, and the intra-school correlations in student responses. In this paper, we adopt a multilevel simultaneous equation modelling approach to assess the impact of school resources on student attainment at age 14. This paper is the first to apply a simultaneous equation model to estimate the impact of school resources on pupil achievement, using the newly available National Pupil Database (NPDB)

Lesion boundary segmentation using level set methods

This paper addresses the issue of accurate lesion segmentation in retinal imagery, using level set methods and a novel stopping mechanism - an elementary features scheme. Specifically, the curve propagation is guided by a gradient map built using a combination of histogram equalization and robust statistics. The stopping mechanism uses elementary features gathered as the curve deforms over time, and then using a lesionness measure, defined herein, ’looks back in time’ to find the point at which the curve best fits the real object. We implement the level set using a fast upwind scheme and compare the proposed method against five other segmentation algorithms performed on 50 randomly selected images of exudates with a database of clinician marked-up boundaries as ground truth

Interfering in a Non-Interference Policy: Defining Star Trek\u27s Prime Directive

The aim of this thesis is to provide a comprehensive definition of the Prime Directive, a concept that was developed in Star Trek: The Original Series, as well as provide a non-fictionalized version of the edict. The Prime Directive is an edict that governs Starfleet not to interfere with a society’s development. The first main section will discuss in further detail why The Original Series account of the Prime Directive was selected. Furthermore, it will discuss how members of academia interpret the Prime Directive. The second main section will be an episode-by-episode analysis of each Prime Directive centered episode to extract the different nuances each episode added to the order. Lastly, this thesis will provide a comprehensive definition of the Prime Directive, determine if The Original Series provides an adequate foundation to base a non-fictionalized Prime Directive on, and then propose an operational one that can be used

Humanitarian Zionism: The Vaad Hatzalah and Abraham Joshua Heschel

This paper explores the history of humanitarian Zionism as espoused by Abraham Joshua Heschel and the Vaad Hatzalah -- an Orthodox Jewish organization operating in the United States during the Holocaust. Both Heschel and the Vaad saw the priority of Zionism, or Jewish nation-building, as the preservation of Torah scholarship and the saving of human life. The importance of this: Zionism during the era of Heschel and the Vaad should be understood with greater detail. Zionism, in its complete history, was not uniquely driven by nationalism or the need for statehood, but a humanitarian message as well. This understanding can 1) dispel the myth that Zionism in its complete history has been a story of militancy and nationalist expansion and 2) create a greater appreciation for the work of Jewish organizations like the Vaad which saved thousands of lives through settlement in Palestine and the social justice ideals of mindful Jewish thinkers like Abraham Joshua Heschel

The start-perranporth zone- transpressional reactivation across a major basement fault in the variscan orogen of S.W. England

The Start-Perranporth Zone is one of a number of E-W trending zones in S.W. England, which are characterised by an anomalous and structurally complex deformation history, and which are thought to reflect the influence of pre-existing basin architecture. The SPZ straddles the Start Complex in S. Devon, and is approximately coincident with the northern margin of the Gramscatho Basin in S. Cornwall. It appears to coincide with significant sedimentological, geochemical and metamorphic transitions, and may mark the site of a pre- to Early Devonian terrane boundary. This terrane boundary may have formed the northern margin to a series of small possibly transtensional basins, including the Start and Gramscatho Basins, in which thick successions accumulated prior to inversion during the Variscan orogeny. The pelitic sequences in these basins (Gramscatho Group sandstones, Start greyschists) are geochemically similar to one another, and to other Rhenohercynian basinal sequences in mainland Europe. Both the Gramscatho and Start basins are characterised by the presence of incipient ocean crust (Lizard ophiolite, Start greenschists), with a strongly depleted N-type MORB signature and evidence of ridge-related sub-oceanic early deformation. The interlayered green and grey schists of the Start Complex are separated from the shallow marine Meadfoot shales to the north by a steep north dipping normal fault, the Start Boundary Fault, which bears evidence of a long-lived movement history. This fault is intimately associated with large volumes of highly altered and replaced basic intrusives, and appears to be the surface manifestation of the basin bounding fault at depth. Approaching the SBF, the strain intensifies, primary folds tighten, the primary cleavage steepens to sub-vertical and mineral stretching lineations switch from SSE plunging (sub-parallel to the Variscan transport direction) to sub-horizontal approximately E-W trending. Immediately adjacent to the SBF, sheath folds occur, suggesting very high along strike shear strains. Small scale structures, e.g. shear bands, refold relationships, etc. consistently indicate that dextral simple shear is important during Variscan shortening. Similar, though somewhat more cryptic, evidence for dextral shear is also seen in the L. Devonian shales north of the SBF. In S. Cornwall there is a similar focusing of high strain along the northern Gramscatho margin, with a tightening of folds, a backsteepening of the primary cleavage, and the development of overprinting late crenulations. Primary stretching lineations lie E-W. There is no evidence for sheath folding on either coast, although broad phyllonite zones bearing dextrally asymmetric quartz augen provide evidence of long-lived dextral shear. Many of the high strain fabrics on the east coast are absent, probably faulted out along a major NW-SE dextral strike-slip fault (the Pentewan Fault).The small scale structural evidence along this zone consistently indicates that dextral transpression was the dominant deformation mechanism during Variscan orogenesis. The structural transitions are also suggestive of fault butttressing, e.g. secondary backfolding, backthrusting, etc. and it appears that the ~E-W trending basin bounding fault acted as an oblique buttress to the NNW directed Variscan nappes, the high angle obliquity of this collision inducing dextral transpression in the shortening cover sequence. This fault buttressing mechanism readily accounts for all of the observed anomalous small scale structures, and the marked along strike persistence of the anomalous zone

Daily Timed Sexual Interaction Induces Moderate Anticipatory Activity in Mice

Anticipation of resource availability is a vital skill yet it is poorly understood in terms of neuronal circuitry. Rodents display robust anticipatory activity in the several hours preceding timed daily access to food when access is limited to a short temporal duration. We tested whether this anticipatory behavior could be generalized to timed daily social interaction by examining if singly housed male mice could anticipate either a daily novel female or a familiar female. We observed that anticipatory activity was moderate under both conditions, although both a novel female partner and sexual experience are moderate contributing factors to increasing anticipatory activity. In contrast, restricted access to running wheels did not produce any anticipatory activity, suggesting that an increase in activity during the scheduled access time was not sufficient to induce anticipation. To tease apart social versus sexual interaction, we tested the effect of exposing singly housed female mice to a familiar companion female mouse daily. The female mice did not show anticipatory activity for restricted female access, despite a large amount of social interaction, suggesting that daily timed social interaction between mice of the same gender is insufficient to induce anticipatory activity. Our study demonstrates that male mice will show anticipatory activity, albeit inconsistently, for a daily timed sexual encounter