1,455 research outputs found
The 2010 MW 6.8 Yushu (Qinghai, China) earthquake: constraints provided by InSAR and body wave seismology
By combining observations from satellite radar, body wave seismology and optical imagery, we have determined the fault segmentation and sequence of ruptures for the 2010 Mw 6.8 Yushu (China) earthquake. We have mapped the fault trace using displacements from SAR image matching, interferometric phase and coherence, and 2.5 m SPOT-5 satellite images. Modeling the event as an elastic dislocation with three segments fitted to the fault trace suggests that the southeast and northwest segments are near vertical, with the central segment dipping 70° to the southwest; slip occurs mainly in the upper 10 km, with a maximum slip of 1.5 m at a depth of 4 km on the southeastern segment. The maximum slip in the top 1 km (i.e., near surface) is up to 1.2 m, and inferred locations of significant surface rupture are consistent with displacements from SAR image matching and field observations. The radar interferograms show rupture over a distance of almost 80 km, much larger than initial seismological and field estimates of the length of the fault. Part of this difference can be attributed to slip on the northwestern segment of the fault being due to an Mw 6.1 aftershock two hours after the main event. The remaining difference can be explained by a non-uniform slip distribution with much of the moment release occurring at depths of less than 10 km. The rupture on the central and southeastern segments of the fault in the main shock propagated at a speed of 2.5 km/s southeastward toward the town of Yushu located at the end of this segment, accounting for the considerable building damage. Strain accumulation since the last earthquake on the fault segment beyond Yushu is equivalent to an Mw 6.5 earthquake
Serum antioxidants as predictors of the adult respiratory distress syndrome in septic patients
Adult respiratory distress syndrome (ARDS) can develop as a complication of various disorders, including sepsis, but it has not been possible to identify which of the patients at risk will develop this serious disorder. We have investigated the ability of six markers, measured sequentially in blood, to predict development of ARDS in 26 patients with sepsis.
At the initial diagnosis of sepsis (6-24 h before the development of ARDS), serum manganese superoxide dismutase concentration and catalase activity were higher in the 6 patients who subsequently developed ARDS than in 20 patients who did not develop ARDS. These changes in antioxidant enzymes predicted the development of ARDS in septic patients with the same sensitivity, specificity, and efficiency as simultaneous assessments of serum lactate dehydrogenase activity and factor VIII concentration. By contrast, serum glutathione peroxidase activity and α1Pi-elastase complex concentration did not differ at the initial diagnosis of sepsis between patients who did and did not subsequently develop ARDS, and were not as effective in predicting the development of ARDS.
Measurement of manganese superoxide dismutase and catalase, in addition to the other markers, should facilitate identification of patients at highest risk of ARDS and allow prospective treatment
Influence of short- and long-term exposure on the biodegradation capacity of activated sludge microbial communities in ready biodegradability tests
Sticky stuff : redefining bedform prediction in modern and ancient environments
This work was funded by the UK Natural Environment Research Council (NERC) under the COHBED project (NE/1027223/1). Paterson was funded by the Marine Alliance for Science and Technology for Scotland (MASTS).The dimensions and dynamics of subaqueous bedforms are well known for cohesionless sediments. However, the effect of physical cohesion imparted by cohesive clay within mixed sand-mud substrates has not been examined, despite its recognized influence on sediment stability. Here we present a series of controlled laboratory experiments to establish the influence of substrate clay content on subaqueous bedform dynamics within mixtures of sand and clay exposed to unidirectional flow. The results show that bedform dimensions and steepness decrease linearly with clay content, and comparison with existing predictors of bedform dimensions, established within cohesionless sediments, reveals significant over-prediction of bedform size for all but the lowermost clay contents examined. The profound effect substrate clay content has on bedform dimensions has a number of important implications for interpretation in a range of modern and ancient environments, including reduced roughness and bedform heights in estuarine systems and the often cited lack of large dune cross-sets in turbidites. The results therefore offer a step change in our understanding of bedform formation and dynamics in these, and many other, sedimentary environments.Publisher PDFPeer reviewe
Sociology and postcolonialism: another 'missing' revolution?
Sociology is usually represented as having emerged alongside European modernity. The latter is frequently understood as sociology's special object with sociology itself a distinctively modern form of explanation. The period of sociology's disciplinary formation was also the heyday of European colonialism, yet the colonial relationship did not figure in the development of sociological understandings. While the recent emergence of postcolonialism appears to have initiated a reconsideration of understandings of modernity, with the development of theories of multiple modernities, I suggest that this engagement is more an attempt at recuperating the transformative aspect of postcolonialism than engaging with its critiques. In setting out the challenge of postcolonialism to dominant sociological accounts, I also address `missing feminist/queer revolutions', suggesting that by engaging with postcolonialism there is the potential to transform sociological understandings by opening up a dialogue beyond the simple pluralism of identity claims
Study of ATLAS sensitivity to FCNC top decays
The ATLAS experiment sensitivity to top quark Flavour Changing Neutral
Current (FCNC) decays was studied at LHC using ttbar events. While one of the
top quarks is expected to follow the dominant Standard Model decay t->bW, the
other decays through a FCNC channel, i.e. t-> Z u(c), t-> gamma u(c) or t-> g
u(c). Different types of analyses, applied to each FCNC decay mode, were
compared. The FCNC branching ratio sensitivity (assuming a 5sigma signal
significance) and 95% confidence level limits on the branching ratios (in the
hypothesis of signal absence) were obtained
The Non-linear Dynamics of Meaning-Processing in Social Systems
Social order cannot be considered as a stable phenomenon because it contains
an order of reproduced expectations. When the expectations operate upon one
another, they generate a non-linear dynamics that processes meaning. Specific
meaning can be stabilized, for example, in social institutions, but all meaning
arises from a horizon of possible meanings. Using Luhmann's (1984) social
systems theory and Rosen's (1985) theory of anticipatory systems, I submit
equations for modeling the processing of meaning in inter-human communication.
First, a self-referential system can use a model of itself for the
anticipation. Under the condition of functional differentiation, the social
system can be expected to entertain a set of models; each model can also
contain a model of the other models. Two anticipatory mechanisms are then
possible: one transversal between the models, and a longitudinal one providing
the modeled systems with meaning from the perspective of hindsight. A system
containing two anticipatory mechanisms can become hyper-incursive. Without
making decisions, however, a hyper-incursive system would be overloaded with
uncertainty. Under this pressure, informed decisions tend to replace the
"natural preferences" of agents and an order of cultural expectations can
increasingly be shaped
The Fayet-Iliopoulos D-term and its renormalisation in softly-broken supersymmetric theories
We consider the renormalisation of the Fayet-Iliopoulos D-term in a
softly-broken abelian supersymmetric theory, and calculate the associated
beta-function through three loops. We show that there exists (at least through
three loops) a renormalisation group invariant trajectory for the coefficient
of the D-term, corresponding to the conformal anomaly solution for the soft
masses and couplings.Comment: 30 pages, Revtex, 15 Figures. Minor changes, and inadvertent omission
of author from this abstract correcte
Applications of scalar attractor solutions to Cosmology
We develop a framework to study the phase space of a system consisting of a
scalar field rolling down an arbitrary potential with varying slope and a
background fluid, in a cosmological setting. We give analytical approximate
solutions of the field evolution and discuss applications of its features to
the issues of quintessence, moduli stabilisation and quintessential inflation.Comment: 9 pages, 7 figures. Accepted for publication in PR
Kindlin-1 regulates epidermal growth factor receptor signalling
Kindler syndrome (KS) is an autosomal recessive genodermatosis that results from mutations in the FERMT1 gene encoding kindlin-1. Kindlin-1 localises to focal adhesion and is known to contribute to the activation of integrin receptors. Most cases of KS show a reduction or complete absence of kindlin-1 in keratinocytes, resulting in defective integrin activation, cell adhesion and migration. However, roles for kindlin-1 beyond integrin activation remain poorly defined. In the current study we show that skin and keratinocytes from KS patients have significantly reduced expression levels of the epidermal growth factor receptor (EGFR), resulting in defective EGF-dependent signalling and cell migration. Mechanistically, we demonstrate that kindlin-1 can associate directly with EGFR in vitro and in keratinocytes in an EGF-dependent, integrin-independent manner and that formation of this complex is required for EGF-dependent migration. We further demonstrate that kindlin-1 acts to protect EGFR from lysosomal-mediated degradation. This reveals a new role for kindlin-1 that has implications for understanding KS disease pathology
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