910 research outputs found
Basement and Regional Structure Along Strike of the Queen Charlotte Fault in the Context of Modern and Historical Earthquake Ruptures
The Queen Charlotte fault (QCF) is a dextral transform system located offshore of southeastern Alaska and western Canada, accommodating similar to 4.4 cm/yr of relative motion between the Pacific and North American plates. Oblique convergence along the fault increases southward, and how this convergence is accommodated is still debated. Using seismic reflection data, we interpret offshore basement structure, faulting, and stratigraphy to provide a geological context for two recent earthquakes, an M-w 7.5 strike-slip event near Craig, Alaska, and an M-w 7.8 thrust event near Haida Gwaii, Canada. We map downwarped Pacific oceanic crust near 54 degrees N, between the two rupture zones. Observed downwarping decreases north and south of 54 degrees N, parallel to the strike of the QCF. Bending of the Pacific plate here may have initiated with increased convergence rates due to a plate motion change at similar to 6 Ma. Tectonic reconstruction implies convergence-driven Pacific plate flexure, beginning at 6 Ma south of a 10 degrees bend the QCF (which is currently at 53.2 degrees N) and lasting until the plate translated past the bend by similar to 2 Ma. Normal-faulted approximately late Miocene sediment above the deep flexural depression at 54 degrees N, topped by relatively undeformed Pleistocene and younger sediment, supports this model. Aftershocks of the Haida Gwaii event indicate a normal-faulting stress regime, suggesting present-day plate flexure and underthrusting, which is also consistent with reconstruction of past conditions. We thus favor a Pacific plate underthrusting model to initiate flexure and accommodation space for sediment loading. In addition, mapped structures indicate two possible fault segment boundaries along the QCF at 53.2 degrees N and at 56 degrees N.USGS Earthquake Hazards External Grants ProgramNational Earthquake Hazards Reduction ProgramUTIG Ewing/Worzel FellowshipInstitute for Geophysic
The role of law and ethics in developing business management as a profession
Currently, business management is far from being recognised as a profession. This paper suggests that a professional spirit should be developed which could function as a filter of commercial reasoning. Broadly, management will not be organised within the framework of a well-established profession unless formal knowledge, licensing, professional autonomy and professional codes of conduct are developed sufficiently. In developing business management as a profession, law may play a key role. Where the idea is that business management should be more professsionalised, managers must show that they are willing to adopt ethical values, while arriving at business decisions. The paper argues that ethics cannot survive without legal regulation, which, in turn, will not be supported by law unless lawyers can find alternative solutions to the large mechanisms of the official society, secured by the monopolised coercion of the nation state. From a micro perspective of law and business ethics, communities can be developed with their own conventions, rules and standards that are generated and sanctioned within the boundaries of the communities themselves
Observations of the geology and geomorphology of the 1999 Marsokhod test site
The Marsokhod rover returned data from six stations that were used to decipher the geomorphology and geology of a region not previously visited by members of the geomorphology field team. Satellite images and simulated descent images provided information about the regional setting. The landing zone was on an alluvial apron flanking a mountain block to the west and playa surface to the east. Rover color images, infrared spectra analysis of the mountains, and the apron surface provided insight into the rock composition of the nearby mountains. From the return data the geomorphology team interpreted the region to consist of compressionally deformed, ancient marine sediments and igneous rocks exposed by more recent extensional tectonics. Unconsolidated alluvial materials blanket the lower flanks of the mountains. An ancient shoreline cut into alluvial material marks a high stand of water during a past, wetter climate period. Playa sediments floor a present-day, seasonally, dry lake. Observations made by the rover using panoramic and close-up (hand specimens—scale) image data and color scene data confirmed the presence of boulders, cobbles, and fines of various provinces. Rover traverses to sites identified as geologically distinct, such as a fan, channel, shoreline, and playa, provided useful clues to the geologic interpretations. Analysis of local rocks was given context only through comparison with distant geologic features. These results demonstrated the importance of a multifaceted approach to site interpretation through comparison of interpretations derived by differing geologic techniques
Cloning and Regulation of Flavonol 3-Sulfotransferase in Cell-Suspension Cultures of Flaveria bidentis
Contrasting Decollement and Prism Properties over the Sumatra 2004-2005 Earthquake Rupture Boundary
Styles of subduction zone deformation and earthquake rupture dynamics are strongly linked, jointly influencing hazard potential. Seismic reflection profiles across the trench west of Sumatra, Indonesia, show differences across the boundary between the major 2004 and 2005 plate interface earthquakes, which exhibited contrasting earthquake rupture and tsunami generation. In the southern part of the 2004 rupture, we interpret a negative-polarity sedimentary reflector ~500 meters above the subducting oceanic basement as the seaward extension of the plate interface. This predécollement reflector corresponds to unusual prism structure, morphology, and seismogenic behavior that are absent along the 2005 rupture zone. Although margins like the 2004 rupture zone are globally rare, our results suggest that sediment properties influence earthquake rupture, tsunami hazard, and prism development at subducting plate boundaries
Integration of professional judgement and decision-making in high-level adventure sports coaching practice
This study examined the integration of professional judgement and decision-making processes in adventure sports coaching. The study utilised a thematic analysis approach to investigate the decision-making practices of a sample of high-level adventure sports coaches over a series of sessions. Results revealed that, in order to make judgements and decisions in practice, expert coaches employ a range of practical and pedagogic management strategies to create and opportunistically use time for decision-making. These approaches include span of control and time management strategies to facilitate the decision-making process regarding risk management, venue selection, aims, objectives, session content, and differentiation of the coaching process. The implication for coaches, coach education, and accreditation is the recognition and training of the approaches that“create time” for the judgements in practice, namely“creating space to think”. The paper concludes by offering a template for a more expertise-focused progression in adventure sports coachin
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Relationship between latent and rebound viruses in a clinical trial of anti-HIV-1 antibody 3BNC117.
A clinical trial was performed to evaluate 3BNC117, a potent anti-HIV-1 antibody, in infected individuals during suppressive antiretroviral therapy and subsequent analytical treatment interruption (ATI). The circulating reservoir was evaluated by quantitative and qualitative viral outgrowth assay (Q2VOA) at entry and after 6 mo. There were no significant quantitative changes in the size of the reservoir before ATI, and the composition of circulating reservoir clones varied in a manner that did not correlate with 3BNC117 sensitivity. 3BNC117 binding site amino acid variants found in rebound viruses preexisted in the latent reservoir. However, only 3 of 217 rebound viruses were identical to 868 latent viruses isolated by Q2VOA and near full-length sequencing. Instead, 63% of the rebound viruses appeared to be recombinants, even in individuals with 3BNC117-resistant reservoir viruses. In conclusion, viruses emerging during ATI in individuals treated with 3BNC117 are not the dominant species found in the circulating latent reservoir, but frequently appear to represent recombinants of latent viruses
Shift invariant preduals of ℓ<sub>1</sub>(ℤ)
The Banach space ℓ<sub>1</sub>(ℤ) admits many non-isomorphic preduals, for
example, C(K) for any compact countable space K, along with many more
exotic Banach spaces. In this paper, we impose an extra condition: the predual
must make the bilateral shift on ℓ<sub>1</sub>(ℤ) weak<sup>*</sup>-continuous. This is
equivalent to making the natural convolution multiplication on ℓ<sub>1</sub>(ℤ)
separately weak*-continuous and so turning ℓ<sub>1</sub>(ℤ) into a dual Banach
algebra. We call such preduals <i>shift-invariant</i>. It is known that the
only shift-invariant predual arising from the standard duality between C<sub>0</sub>(K)
(for countable locally compact K) and ℓ<sub>1</sub>(ℤ) is c<sub>0</sub>(ℤ). We provide
an explicit construction of an uncountable family of distinct preduals which do
make the bilateral shift weak<sup>*</sup>-continuous. Using Szlenk index arguments, we
show that merely as Banach spaces, these are all isomorphic to c<sub>0</sub>. We then
build some theory to study such preduals, showing that they arise from certain
semigroup compactifications of ℤ. This allows us to produce a large number
of other examples, including non-isometric preduals, and preduals which are not
Banach space isomorphic to c<sub>0</sub>
Observation of the geology and geomorphology of the 1999 Marsokhod test site
The Marsokhod rover returned data from six stations that were used to decipher the geomorphology and geology of a region not previously visited by members of the geomorphology field team. Satellite images and simulated descent images provided information about the regional setting. The landing zone was on an alluvial apron flanking a mountain block to the west and a playa surface to the east. Rover color images, infrared spectra analysis of the mountains, and the apron surface provided insight into the rock composition of the nearby mountains. From the return data the geomorphology team interpreted the region to consist of compressionally deformed, ancient marine sediments and igneous rocks exposed by more recent extensional tectonics. Unconsolidated alluvial materials blanket the lower flanks of the mountains. Bn ancient shoreline cut into alluvial material marks a high stand of water during a past, wetter climate period. Playa sediments floor a present-day, seasonally, dry lake. Observations made by the rover using panoramic and close-up (hand specimens-scale) image data and color scene data confirmed the presence of boulders, cobbles, and fines of various provinces. Rover traverses to sites identified as geologically distinct, such as fan, channel, shoreline, and playa, provided useful clues to the geologic interpretations. Analysis of local rocks was given concert only through comparison with distant geologic features. These results demonstrated the importance of a multifaceted approach to site interpretation through comparison of interpretations derived by differing geologic techniques
Tsunami waves extensively resurfaced the shorelines of an early Martian ocean
It has been proposed that ~3.4 billion years ago an ocean fed by enormous
catastrophic floods covered most of the Martian northern lowlands. However, a
persistent problem with this hypothesis is the lack of definitive
paleoshoreline features. Here, based on geomorphic and thermal image mapping
in the circum-Chryse and northwestern Arabia Terra regions of the northern
plains, in combination with numerical analyses, we show evidence for two
enormous tsunami events possibly triggered by bolide impacts, resulting in
craters ~30 km in diameter and occurring perhaps a few million years apart.
The tsunamis produced widespread littoral landforms, including run-up water-
ice-rich and bouldery lobes, which extended tens to hundreds of kilometers
over gently sloping plains and boundary cratered highlands, as well as
backwash channels where wave retreat occurred on highland-boundary surfaces.
The ice-rich lobes formed in association with the younger tsunami, showing
that their emplacement took place following a transition into a colder global
climatic regime that occurred after the older tsunami event. We conclude that,
on early Mars, tsunamis played a major role in generating and resurfacing
coastal terrains
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