We use InSAR and body‐wave seismology to determine independent source parameters for the 6th April 2009 Mw 6.3 L'Aquila earthquake and confirm that the earthquake ruptured a SW‐dipping normal fault ...with ∼0.6–0.8 m slip. The causative Paganica fault had been neglected relative to other nearby range‐frontal faults, partly because it has a subdued geomorphological expression in comparison with these faults. The L'Aquila earthquake occurred in an area with a marked seismic deficit relative to geodetically determined strain accumulation. We use our source model to calculate stress changes on nearby faults produced by the L'Aquila earthquake and we find that several of these faults have been brought closer to failure.
The formation, storage and chemical differentiation of magma in the Earth's crust is of fundamental importance in igneous geology and volcanology. Recent data are challenging the high-melt-fraction ...'magma chamber' paradigm that has underpinned models of crustal magmatism for over a century, suggesting instead that magma is normally stored in low-melt-fraction 'mush reservoirs'
. A mush reservoir comprises a porous and permeable framework of closely packed crystals with melt present in the pore space
. However, many common features of crustal magmatism have not yet been explained by either the 'chamber' or 'mush reservoir' concepts
. Here we show that reactive melt flow is a critical, but hitherto neglected, process in crustal mush reservoirs, caused by buoyant melt percolating upwards through, and reacting with, the crystals
. Reactive melt flow in mush reservoirs produces the low-crystallinity, chemically differentiated (silicic) magmas that ascend to form shallower intrusions or erupt to the surface
. These magmas can host much older crystals, stored at low and even sub-solidus temperatures, consistent with crystal chemistry data
. Changes in local bulk composition caused by reactive melt flow, rather than large increases in temperature, produce the rapid increase in melt fraction that remobilizes these cool- or cold-stored crystals. Reactive flow can also produce bimodality in magma compositions sourced from mid- to lower-crustal reservoirs
. Trace-element profiles generated by reactive flow are similar to those observed in a well studied reservoir now exposed at the surface
. We propose that magma storage and differentiation primarily occurs by reactive melt flow in long-lived mush reservoirs, rather than by the commonly invoked process of fractional crystallization in magma chambers
.
Objective To examine prospectively the association between muscular strength and mortality from all causes, cardiovascular disease, and cancer in men.Design Prospective cohort study.Setting Aerobics ...centre longitudinal study.Participants 8762 men aged 20-80.Main outcome measures All cause mortality up to 31 December 2003; muscular strength, quantified by combining one repetition maximal measures for leg and bench presses and further categorised as age specific thirds of the combined strength variable; and cardiorespiratory fitness assessed by a maximal exercise test on a treadmill.Results During an average follow-up of 18.9 years, 503 deaths occurred (145 cardiovascular disease, 199 cancer). Age adjusted death rates per 10 000 person years across incremental thirds of muscular strength were 38.9, 25.9, and 26.6 for all causes; 12.1, 7.6, and 6.6 for cardiovascular disease; and 6.1, 4.9, and 4.2 for cancer (all P<0.01 for linear trend). After adjusting for age, physical activity, smoking, alcohol intake, body mass index, baseline medical conditions, and family history of cardiovascular disease, hazard ratios across incremental thirds of muscular strength for all cause mortality were 1.0 (referent), 0.72 (95% confidence interval 0.58 to 0.90), and 0.77 (0.62 to 0.96); for death from cardiovascular disease were 1.0 (referent), 0.74 (0.50 to 1.10), and 0.71 (0.47 to 1.07); and for death from cancer were 1.0 (referent), 0.72 (0.51 to 1.00), and 0.68 (0.48 to 0.97). The pattern of the association between muscular strength and death from all causes and cancer persisted after further adjustment for cardiorespiratory fitness; however, the association between muscular strength and death from cardiovascular disease was attenuated after further adjustment for cardiorespiratory fitness.Conclusion Muscular strength is inversely and independently associated with death from all causes and cancer in men, even after adjusting for cardiorespiratory fitness and other potential confounders.
Injectable biomimetic hydrogels have great potential for use in regenerative medicine as cellular delivery vectors. However, they can suffer from issues relating to hypoxia, including poor cell ...survival, differentiation, and functional integration owing to the lack of an established vascular network. Here we engineer a hybrid myoglobin:peptide hydrogel that can concomitantly deliver stem cells and oxygen to the brain to support engraftment until vascularisation can occur naturally. We show that this hybrid hydrogel can modulate cell fate specification within progenitor cell grafts, resulting in a significant increase in neuronal differentiation. We find that the addition of myoglobin to the hydrogel results in more extensive innervation within the host tissue from the grafted cells, which is essential for neuronal replacement strategies to ensure functional synaptic connectivity. This approach could result in greater functional integration of stem cell-derived grafts for the treatment of neural injuries and diseases affecting the central and peripheral nervous systems.
Vascular and angiogenic processes provide an important target for novel cancer therapeutics. Dynamic contrast-enhanced magnetic resonance imaging is being used increasingly to noninvasively monitor ...the action of these therapeutics in early-stage clinical trials. This publication reports the outcome of a workshop that considered the methodology and design of magnetic resonance studies, recommending how this new tool might best be used.
The use of organic materials presents a tremendous opportunity to significantly impact the functionality and pervasiveness of large-area electronics. Commercialization of this technology requires ...reduction in manufacturing costs by exploiting inexpensive low-temperature deposition and patterning techniques, which typically lead to lower device performance. We report a low-cost approach to control the microstructure of solution-cast acene-based organic thin films through modification of interfacial chemistry. Chemically and selectively tailoring the source/drain contact interface is a novel route to initiating the crystallization of soluble organic semiconductors, leading to the growth on opposing contacts of crystalline films that extend into the transistor channel. This selective crystallization enables us to fabricate high-performance organic thin-film transistors and circuits, and to deterministically study the influence of the microstructure on the device characteristics. By connecting device fabrication to molecular design, we demonstrate that rapid film processing under ambient room conditions and high performance are not mutually exclusive.
Ice loss from the world's glaciers and ice sheets contributes to sea level rise, influences ocean circulation, and affects ecosystem productivity. Ongoing changes in glaciers and ice sheets are ...driven by submarine melting and iceberg calving from tidewater glacier margins. However, predictions of glacier change largely rest on unconstrained theory for submarine melting. Here, we use repeat multibeam sonar surveys to image a subsurface tidewater glacier face and document a time-variable, three-dimensional geometry linked to melting and calving patterns. Submarine melt rates are high across the entire ice face over both seasons surveyed and increase from spring to summer. The observed melt rates are up to two orders of magnitude greater than predicted by theory, challenging current simulations of ice loss from tidewater glaciers.
We use InSAR and body wave modelling to determine the faulting parameters for a series of five Mw 5.9–7.1 normal faulting earthquakes that occurred during 2008, including the March 20 Yutian ...earthquake (Mw 7.1), one of the largest normal faulting events to have occurred recently on the continents. We also study three earlier normal faulting earthquakes that occurred in southern Tibet between 1992 and 2005. Coseismic deformation for each of these eight events is measured with ascending and descending interferograms from ENVISAT, ERS and ALOS SAR data. Elastic dislocation modelling of the line-of-sight InSAR displacements and body wave seismological modelling of P and SH waves are used to estimate fault parameters and are found to be in good agreement for all the events studied. The use of InSAR to measure deformation allows a relatively precise determination of the fault location in addition to resolving the focal plane ambiguity. Only five of the eight events are associated with a clear surface topographic feature, suggesting that an underestimation of the amount of extension would result from using the surface expressions of normal faulting alone. The observations, in all cases, are consistent with slip on planar surfaces, with dips in the range 40–50°, that penetrates the uppermost crust to a depth of 10–15 km. We find no evidence for active low-angle (dip less than 30°) normal faulting. The contribution of the normal faulting to overall extension estimated by summing seismic moments over earthquakes for the past 43 yr is 3–4 mm yr−1, or 15–20 per cent of the rates of extension measured across the plateau using GPS. 85 per cent of the moment release in normal faulting over the past 43 yr has occurred in regions whose surface height exceeds 5 km. This observation adds weight to the suggestions that the widespread normal faulting on the plateau is the result of variations in the gravitational potential energy of the lithosphere.
The deformation mechanisms of the
β
-Ti alloy, Gum metal, were investigated with the aid of in situ synchrotron X-ray diffraction (SXRD) and transmission electron microscopy (TEM). SXRD showed that ...Gum metal undergoes a reversible stress-induced martensitic (
α
″
) phase transformation. Oxygen increases the resistance to shear by increasing
C
′
and limits the extent of
α
″
growth. Prior deformation aids
α
″
formation of by providing nuclei, such as
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1
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2}
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twins and stress-induced
ω
plates. The formation of twins and
ω
plates, both observed in TEM, are believed to be a result of a low
G
1
1
1
in this alloy. Features similar to the “giant faults” seen previously were observed in TEM; their formation is believed to be a result of
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shear.
We analyse a 154 MHz image made from a 12 h observation with the Murchison Widefield Array (MWA) to determine the noise contribution and behaviour of the source counts down to 30 mJy. The MWA image ...has a bandwidth of 30.72 MHz, a field-of-view within the half-power contour of the primary beam of 570...deg super( 2), a resolution of 2.3 arcmin and contains 13 458 sources above 5... The rms noise in the centre of the image is 4-5...mJy beam super( -1). The MWA counts are in excellent agreement with counts from other instruments and are the most precise ever derived in the flux density range 30-200 mJy due to the sky area covered. Using the deepest available source count data, we find that the MWA image is affected by sidelobe confusion noise at the ...3.5 mJy beam super( -1) level, due to incompletely peeled and out-of-image sources, and classical confusion becomes apparent at ...1.7 mJy beam super( -1). This work highlights that (i) further improvements in ionospheric calibration and deconvolution imaging techniques would be required to probe to the classical confusion limit and (ii) the shape of low-frequency source counts, including any flattening towards lower flux densities, must be determined from deeper ...150 MHz surveys as it cannot be directly inferred from higher frequency data. (ProQuest: ... denotes formulae/symbols omitted.)
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