bluuebunny/crossref_metadata_2025 huggingface dataset:
SOME REMARKS ON DEPTH OF DEAD ENDS IN GROUPS
Authors: LEHNERT JÖRG
Published: June 2009

It is known, that the existence of dead ends (of arbitrary depth) in the Cayley graph of a group depends on the chosen set of generators. Nevertheless there exist many groups, which do not have dead ends of arbitrary depth with respect to any set of generators. Partial results in this direction were obtained by Šunić and by Warshall. We improve these results by showing that abelian groups have only finitely many dead ends and that groups with more than one end (in the sense of Hopf and Freudenthal) have only dead ends of bounded depth. Only few examples of groups with unbounded dead end depth are known. We show that the Houghton group H2 with respect to the standard generating set is a further example. In addition we introduce a stronger notion of depth of a dead end, called strong depth. The Houghton group H2 has unbounded strong depth with respect to the same standard generating set.
STATEFINDER PARAMETERS FOR THE QUANTUM EFFECTIVE YANG–MILLS CONDENSATE DARK ENERGY MODEL
Authors: TONG MINGLEI , ZHANG YANG , XIA TIANYANG
Published: June 2009

The quantum effective Yang–Mills condensate (YMC) dark energy model has some distinctive features so that it naturally solves the coincidence problem and, at the same time, is able to give an equation of state w crossing -1. In this work we further employ the statefinder pair (r,s), introduced by Sahni et al., to diagnose the YMC model for three cases: the noncoupling, the YMC decaying into matter only, and the YMC decaying into both matter and radiation. The trajectories (r,s) and (r,q), and the evolutions r(z) and s(z), are explicitly presented. It is found that the YMC model in all three cases has r ≃ 1 for z < 10 and s ≃ 0 for z < 5 with only small deviations, ≃ 0.02, quite close to the cosmological constant model (LCDM), but is obviously differentiated from other dark energy models, such as quiessence or kinessence.
GRAVITATION, ELECTROMAGNETISM AND THE COSMOLOGICAL CONSTANT IN PURELY AFFINE GRAVITY
Authors: POPŁAWSKI NIKODEM J.
Published: June 2009

The Eddington Lagrangian in the purely affine formulation of general relativity generates the Einstein equations with the cosmological constant. The Ferraris–Kijowski purely affine Lagrangian for the electromagnetic field, which has the form of the Maxwell Lagrangian with the metric tensor replaced by the symmetrized Ricci tensor, is dynamically equivalent to the Einstein–Maxwell Lagrangian in the metric formulation. We show that the sum of the two affine Lagrangians is dynamically inequivalent to the sum of the analogous Lagrangians in the metric–affine/metric formulation. We also show that such a construction is valid only for weak electromagnetic fields. Therefore the purely affine formulation that combines gravitation, electromagnetism and the cosmological constant cannot be a simple sum of terms corresponding to separate fields. Consequently, this formulation of electromagnetism seems to be unphysical, unlike the purely metric and metric–affine pictures, unless the electromagnetic field couples to the cosmological constant.
A NOTE ON THE CONNECTION BETWEEN THE UNIVERSAL RELAXATION BOUND AND THE COVARIANT ENTROPY BOUND
Authors: PESCI ALESSANDRO
Published: June 2009

A recently formulated universal lower bound to the characteristic relaxation times of perturbed thermodynamic systems, derived from quantum information theory and (classical) thermodynamics and known to be saturated for (certain) black holes, is investigated in the light of the gravity–thermodynamics connection. A statistical-mechanical property, unrelated to gravity, essential for the validity of the generalized covariant entropy bound, namely the existence of a lower-limiting value l* for the size of thermodynamic systems, is found to provide a way to understand this universal relaxation bound, thus regardless of the kind of foundations (i.e. whether conventional or information-based) of the statistical-mechanical description. As a by-product an example of a conventional system (i.e. not a black hole) seemingly saturating the universal relaxation bound is provided.
ACCELERATION AND DECELERATION IN THE CURVATURE-INDUCED PHANTOM MODEL OF THE LATE AND FUTURE UNIVERSE: COSMIC COLLAPSE AND ITS QUANTUM ESCAPE
Authors: SRIVASTAVA S. K. , DUTTA J.
Published: June 2009

In this paper, the cosmology of the late and future universe is obtained from f(R) gravity with nonlinear curvature terms R2 and R3 (R is the Ricci scalar curvature). It is different from f(R) dark energy models where nonlinear curvature terms are taken as a gravitational alternative to dark energy. In the present model, neither linear nor nonlinear curvature terms are taken as dark energy. Rather, dark energy terms are induced by curvature terms and appear in the Friedmann equation derived from f(R) gravitational equations. This approach has an advantage over f(R) dark energy models in three ways: (i) results are consistent with WMAP observations, (ii) dark matter is produced from the gravitational sector and (iii) the universe expands as ~ t2/3 during dominance of the curvature-induced dark matter, which is consistent with the standard cosmology. Curvature-induced dark energy mimics phantom and causes late acceleration. It is found that transition from matter-driven deceleration to acceleration takes place at the redshift 0.36 at time 0.59 t0 (t0 is the present age of the universe). Different phases of this model, including acceleration and deceleration during the phantom phase, are investigated. It is found that expansion of the universe will stop at the age of 3.87 t0 + 694.4 kyr. After this epoch, the universe will contract and collapse by the time of 336.87 t0 + 694.4 kyr. Further, it is shown that cosmic collapse obtained from classical mechanics can be avoided by making quantum gravity corrections relevant near the collapse time due to extremely high energy density and large curvature analogous to the state of the very early universe. Interestingly, the cosmological constant is also induced here; it is extremely small in the classical domain but becomes very high in the quantum domain. This result explains the largeness of the cosmological constant in the early universe due to quantum gravity effects during this era and its very low value in the present universe due to negligible quantum effect in the late universe.
CLASSICAL PRIMARY SUBMODULES AND DECOMPOSITION THEORY OF MODULES
Authors: BAZIAR M. , BEHBOODI M.
Published: June 2009

We introduce the notion of classical primary submodules that generalizes the concept of primary ideals of commutative rings to modules. Existence and uniqueness of classical primary decompositions in finitely generated modules over one-dimensional Noetherian domains are proved.
MINIMAL IRREDUCIBILITY AND THE UNIPOTENT CHARACTERS OF GROUPS OF TYPE BmAND Cm
Authors: DI MARTINO L. , PELLEGRINI M. A. , WEIGEL TH.
Published: June 2009

In this paper we prove that the (non-trivial) irreducible complex unipotent characters of a finite classical group G of type Bmor Cmin odd characteristic are reducible over any proper subgroup of G, apart from very few notable exceptions.
ON SMALL INJECTIVE RINGS AND MODULES
Authors: THUYET LE VAN , QUYNH TRUONG CONG
Published: June 2009

A right R-module MR is called small injective if every homomorphism from a small right ideal to MR can be extended to an R-homomorphism from RR to MR. A ring R is called right small injective, if the right R-module RR is small injective. We prove that R is semiprimitive if and only if every simple right (or left) R-module is small injective. Further we show that the Jacobson radical J of a ring R is a noetherian right R-module if and only if, for every small injective module ER, E(ℕ) is small injective.
N-ARY OPERATIONS WITH LONG PRE-PERIODS
Authors: Denecke K. , Ratanaprasert Ch.
Published: June 2009

Iterating a unary operation f defined on the finite set A with |A| = k one obtains the descending chain [Formula: see text]

The least integer λ(f) with Imfλ(f) = Imfλ(f)+1 is called the pre-period of f. The pre-period of f is an integer between 0 and k - 1. If λ(f) = k - 1 and k ≥ 1, then f is called a long-tailed (LT)-operation and if λ(f) = k - 2 for k ≥ 2, f is said to be an (LT1)-operation. Unary (LT)- and (LT1)-operations and their invariant equivalence relations are characterized in [5]. In [6] these results are extended to partial operations. In this paper we consider the iteration of n-ary operations for n > 1, define and characterize (LT)- and (LT1)- operations and their invariant equivalence relations. The results can be applied in all fields where iteration and recursion plays a role.
ON THE ISOCLINISM OF A PAIR OF LIE ALGEBRAS AND FACTOR SETS
Authors: Moghaddam Mohammad Reza R. , Parvaneh Foroud
Published: June 2009

In 1940, P. Hall introduced the concept of isoclinism on the class of all groups. In the present article we study the notion of isoclinism on a pair of Lie algebras, which forms an equivalence relation and show that each equivalence class contains a stem pair of Lie algebras, which has minimal dimension among the finite dimensional pairs of Lie algebras. Finally, some more results are obtained when two isoclinic pairs of Lie algebras are given.
ON PSEUDO CYCLIC RICCI SYMMETRIC MANIFOLDS
Authors: Shaikh Absos Ali , Hui Shyamal Kumar
Published: June 2009

The object of the present paper is to introduce a type of non-flat Riemannian manifold called pseudo cyclic Ricci symmetric manifold and study its geometric properties. Among others it is shown that a pseudo cyclic Ricci symmetric manifold is a special type of quasi-Einstein manifold. In this paper we also study conformally flat pseudo cyclic Ricci symmetric manifolds and prove that such a manifold can be isometrically immersed in a Euclidean manifold as a hypersurface.
NECESSARY OPTIMALITY CONDITIONS FOR SUPER MINIMIZERS IN STRUCTURAL PROBLEMS OF MULTIOBJECTIVE OPTIMIZATION
Authors: Zeng Lu-Chuan
Published: June 2009

The primary goal of this paper is to study the so-called super minimizers of the sum F1 + F2 related to the concept of super efficiency in constrained problems of multiobjective optimization, where each cost mapping Fi is generally set-valued for i = 1, 2. We will derive necessary conditions (of the subdifferential type) for super minimizers of the sum F1 + F2 on the basis of advanced tools of variational analysis and generalized differentiation that are new in both finite-dimensional and infinite-dimensional settings for problems with single-valued and set-valued objectives.
Fluid regime in continental subduction zones: petrological insights from ultrahigh-pressure metamorphic rocks
Authors: Zheng Yong-Fei
Published: June 2009

Intensive studies of ultrahigh-pressure (UHP) metamorphic rocks in continental collision zones have provided petrological insights into the fluid regime during subduction and exhumation. Recent studies in the Dabie–Sulu orogen of China have made important contributions to understanding fluid action in such systems, hence these rocks are the main focus of this review. Sources of metamorphic fluid can be deduced from study of hydrous minerals, structural hydroxyl and molecular water in nominally anhydrous minerals. Fluid and solid inclusions of UHP metamorphic minerals are also a record of fluid action in deep subduction zones. The presence or absence of metamorphic fluid during subduction and exhumation dictates zircon growth and recrystallization, making available materials for U–Pb dating. Isotopic dating demonstrates that after peak UHP metamorphism, retrograde fluid with deuteric origin became active. The decomposition of hydrous minerals and the exsolution of molecular water and structural hydroxyl during exhumation can provide sufficient amounts of aqueous fluid for quartz veining and amphibolite-facies retrogression within UHP slabs. Aqueous fluid released by the exsolution of molecular water and structural hydroxyl from UHP nominally anhydrous minerals is characterized by low salinity and light hydrogen and oxygen isotope compositions. Therefore, one part of the UHP slab is a source of aqueous fluid, whereas another part is a sink. In both cases, the fluid action during subduction and exhumation is episodic rather than continuous.

Supplementary material:

A description of the Dabie–Sulu UHP metamorphic rocks, analytical methods, LA-ICPMS zircon U–Pb isotope data and rare earth element compositions are available at
http://www.geolsoc.org.uk/SUP18355
.
Inclusion study in zircon from ultrahigh-pressure metamorphic rocks in the Kokchetav massif: an excellent tracer of metamorphic history
Authors: Katayama Ikuo , Maruyama Shigenori
Published: June 2009

Zircon is an excellent material to preserve the complex history of ultrahigh-pressure (UHP) metamorphic rocks, whereas mineralogical evidence of UHP conditions is mostly obliterated in matrix assemblages as a result of extensive retrograde overprinting during exhumation. Zircons from the Kokchetav UHP–HP massif contain numerous inclusions of graphite, quartz, garnet, omphacite, jadeite, phengite, phlogopite, rutile, albite, K-feldspar, amphibole, zoisite, kyanite, calcite, dolomite, apatite and monazite, as well as the diagnostic UHP minerals, such as microdiamond and coesite, which were identified by laser Raman spectroscopy. The internal structure of zircon displays a distinct zonation, which comprises an inherited core, a wide mantle and an outer rim, each with distinctive inclusion micro-assemblages. The low-pressure mineral inclusions, such as graphite, quartz and albite, are common in the inherited core and thin outer rim, whereas diamond, coesite and jadeite occupy the mantle domain. The zircon core and outer rim are of detrital and relatively low-grade metamorphic origin, whereas the mantle domain is of HP to UHP metamorphic origin. The mineral assemblages and chemistry of inclusions preserved in zircon have been used to constrain the metamorphic
P
–
T
path of the Kokchetav UHP–HP rocks, and indicate peak metamorphism at 60–80 kbar and 970–1100 °C followed by nearly isothermal decompression at 10 kbar and
c
. 800 °C. Sensitive high-resolution ion microprobe U–Pb spot analyses of the zoned zircon indicate four discrete ages of the Kokchetav metamorphic evolution: (1) a Middle Proterozoic protolith age; (2) 537 ± 9 Ma for UHP metamorphism; (3) 507 ± 8 Ma for the late-stage amphibolite-facies overprint; (4) 456–461 Ma for post-orogenic thermal events. This indicates that Middle Proterozoic supracrustal protoliths of the Kokchetav UHP–HP rocks were subducted to mantle depths in the Middle Cambrian, and exhumed to mid-crustal levels in the Late Cambrian. The zonal arrangement of inclusions and the presence of coesite and diamond without back reaction imply that aqueous fluids were low to absent within zircon, and that zircon is capable of retaining minerals of each metamorphic stage. We suggest that the study of inclusions in zircon is a powerful method to clarify the multiple stages and timing of metamorphic evolution of UHP–HP rocks, the evidence for which has been more or less obliterated in the host rock.
Recent progress in Scandian ultrahigh-pressure metamorphism in the northernmost domain of the Western Gneiss Complex, SW Norway: continental subduction down to 180–200 km depth
Authors: Roermund Herman van
Published: June 2009

Earlier workers established 20 kbar and 750–800 °C as being the maximum Scandian metamorphic grade for the Caledonized basement units in the northernmost ultrahigh-pressure metamorphic (UHPM) domain of the Western Gneiss Region, SW Norway. These early pressure estimates were entirely based on jadeite isopleths applied to bimineralic eclogites; low Al values in orthopyroxene from opx-eclogites were interpreted to be due to ’disequilibrium effects'. After the initial discovery of microdiamond and majoritic garnet in the area, the low Al
2
O
3
isopleths in opx (cores), ranging from 0.15 to 1.50 wt% in newly discovered and already known occurrences of ’internal' and ’external' opx eclogites–websterites, were reinvestigated and taken as the first indicator that metamorphic grade, on a regional scale, occurred at much higher pressures than previously thought. Regional-scale diamond-grade UHPM conditions were subsequently demonstrated by
in situ
microdiamond discoveries in two widely separated orthopyroxene eclogite–websterite localities included in Mg–Cr (mantle-derived) and Fe–Ti type (crust-derived) peridotite–websterite bodies, leading to a simple strategy for
in situ
microdiamond recognition, described here for the first time. All
in situ
microdiamonds are associated with multiphase solid-inclusion assemblages interpreted to be crystallized from Scandian supercritical, dense, COH-rich subduction zone fluids. In addition, the recent discovery at Fjørtoft of a second, Scandian, majoritic garnet generation (in garnet websterites enclosed in garnet peridotite), having enriched light REE (LREE) patterns (in clinopyroxene and garnet), contrasts strongly to the Archaean–mid-Proterozoic LREE-depleted majoritic garnet patterns (and exsolved pyroxenes) discovered in garnet peridotites from Otrøy. The latter is strong evidence that Scandian continental subduction (and eduction) occurred down to 180–200 km depths, making the northernmost UHPM domain by far the deepest subducted (and educted) part of the Western Gneiss Complex. Such a conclusion is also consistent with (some) geothermobarometric results from internal and external orthopyroxene eclogites and garnet websterites showing results indicative of pressure–temperature estimates deep in the diamond-eclogite facies (850–950 °C and 5.5–6.5 GPa ).

Supplementary material:

EMP mineral analyses of Mageroy and Raknestangen external opx eclogites, and diagrams showing EMP Grt, Opx and Cpx analyses of Mageroy and Raknestangen opx eclogite bodies are available at
http://www.geolsoc.org/SUP18356
.
Subduction of continental crust, the origin of post-orogenic granitoids (and anorthosites?) and the evolution of Fennoscandia
Authors: Brueckner Hannes K.
Published: June 2009

Slices of silica-rich continental crust subducted into the mantle during collision may undergo metamorphism and exhumation towards the surface as coherent high-pressure or ultrahigh-pressure (HP or UHP) terranes or, if stalled in the mantle, melting and return towards the surface as magmas, or a combination of these two processes. Some exposed HP or UHP terranes contain anatectic granitoids demonstrating that melting does occur during exhumation. Therefore crust trapped in the mantle should also melt when radioactive heating and/or conductive heating raise temperatures to the appropriate solidus. Terranes with hydrous phases will melt readily through hydrate-breakdown reactions. Terranes lacking hydrous phases may require adiabatic decompression to melt, possibly as heated quartz-rich crust becomes ductile and rises diapirically. The magmas generated will intrude the overlying plate to form late-, post- and possibly anorogenic granitoids, depending on the time required to reach solidus temperatures. Geochemical characteristics will depend on
P
–
T
conditions, the chemistry and mineralogy of the subducted terrane (especially the presence of hydrous phases), and the amount of melt interaction with the mantle. The removal of sialic upper crust may strand the denser mafic lower crust, which subsequently could melt to generate anorogenic anorthosites, Fe–K granitoids and related rocks. The evolution of the Fennoscandian Shield documents a change from slab melting in the Mesoproterozoic to combined melting and exhumation in the Neoproterozoic to intact exhumation without significant melting in the Palaeozoic.
Widespread bedding-parallel veins of fibrous calcite (’beef') in a mature source rock (Vaca Muerta Fm, Neuquén Basin, Argentina): evidence for overpressure and horizontal compression
Authors: Rodrigues Nuno , Cobbold Peter R. , Loseth Helge , Ruffet Gilles
Published: June 2009

In the Neuquén Basin of Argentina, ’beef' (bedding-parallel veins of fibrous calcite) is widespread within Late Jurassic black mudstones. A typical vein consists of two grey inner zones and two white outer zones. The inner zones contain inclusions of wall rock and hydrocarbons. Calcite fibres are perpendicular to the margins. In the outer zones, the angle between fibre and margin varies from about 45° at the vein tips to 90° in the centre. Imprints of fossils are offset, proving that the fibres have grown antitaxially. We infer that the veins opened in two phases. During Phase 1, the opening was vertical, against gravity. During Phase 2, the veins resisted tectonic shortening, so that shear stresses acted at the margins. The senses of shear account for the fibre angles. At outcrop, igneous intrusive rocks have cut and metamorphosed the veins. From burial curves, maturity calculations, growth strata, and ages of igneous intrusions, we estimate that the inner zones of the beef formed in the oil window, during the Aptian to Albian, and that the outer zones formed in the gas window, during the Cenomanian to Campanian. We infer that the beef is evidence for fluid overpressure during hydrocarbon generation.
Palaeocene–Recent plate boundaries in the NE Atlantic and the formation of the Jan Mayen microcontinent
Authors: Gaina C. , Gernigon L. , Ball P.
Published: June 2009

Breakup and sea-floor spreading between Greenland and Eurasia established a series of new plate boundaries in the North Atlantic region since the Late Palaeocene. A conventional kinematic model from pre-breakup to the present day assumes that Eurasia and Greenland moved apart as a two-plate system. However, new regional geophysical datasets and quantitative kinematic parameters indicate that this system underwent several adjustments since its inception and suggest that additional short-lived plate boundaries existed in the NE Atlantic. Among the consequences of numerous plate boundary relocations is the formation of a highly extended or even fragmented Jan Mayen microcontinent and subsequent deformation of its margins and surrounding regions. The major Oligocene plate boundary reorganization (and microcontinent formation) might have been precluded by various ridge propagations and/or short-lived triple junctions NE and possibly SW of the Jan Mayen microcontinent from the inception of sea-floor spreading (54 Ma) to C18 (40 Ma). Our model implies a series of failed ridges offshore the Faeroe Islands, a northern propagation of the Aegir Ridge NE of the Jan Mayen microcontinent, and a series of triple junctions and/or propagators in the southern Greenland Basin.
Fluid transfers in a carbonate-gaseous aquifer through the local tectonic and geodynamic history
Authors: Durand Véronique , Léonardi Véronique , Deffontaines Benoît , Macquar Jean-Claude
Published: June 2009

A multidisciplinary approach was developed to analyse the impact of the various tectonic joints on water and gas transfers in the carbonate aquifer of Quézac (southern Massif Central, France). Microtectonic measurements confirmed the local tectonic history and the structural map was completed by a morphostructural approach, using detailed photointerpretation of both aerial photographs and a digital elevation model. The past fluid transfers were discussed on the basis of field observations and the possible geodynamic context. The present fluid transfers observed in the field were related to four main groups of tectonic joints, based on a tectonic and morphostructural approach. The history of tectonic constraints, geodynamic context and fluid transfers was then reconstructed. It highlighted the major role of the north–south tectonic joints for water flows, followed by east–west joints, because of their longest karstification history. Joints with NW–SE and NE–SW orientations, which were more recently karstified, appeared to have less influence on water transfers. The weak gas production at the surface of north–south faults was explained by its dispersion owing to their intense karstification. On the basis of the innovative multidisciplinary approach, we propose a model for the water and gas preferential flow paths, taking the local tectonic and geodynamic context into account.
The Tethyan Himalaya: palaeogeographical and tectonic constraints from Ordovician palaeomagnetic data
Authors: TORSVIK TROND H. , PAULSEN TIMOTHY S. , HUGHES NIGEL C. , MYROW PAUL M. , GANERØD MORGAN
Published: June 2009

To test whether the Tethyan Himalaya were part of the northern margin of India in the early Palaeozoic we have produced the first primary palaeomagnetic data (bedding-corrected declination 267.5°, inclination 63.0°, α95= 10°; pole latitude 20.2°N, longitude 28.6°E) from low metamorphic grade Ordovician red beds in the Tethyan Himalaya (Shian Formation). The palaeomagnetic data are of excellent quality, and a statistically positive fold test combined with a comparison with late Cambrian–Ordovician Gondwana poles suggests a primary hematite-bearing magnetization, acquired between 470 and 500 Ma. This is in excellent agreement with stratigraphic, faunal and provenance age estimates, and the palaeomagnetic data demonstrate that the Tethyan Himalaya must have been located in proximity to the Indian craton during early Ordovician times, and are therefore consistent with a continuous margin at that time. The Shian Formation pole overlaps with 470–500 Ma Gondwana poles, but an even better fit can be obtained by invoking a post-Ordovician clockwise rotation of 13° ± 4°. Such a rotation is similar in both sense and magnitude to clockwise rotations recorded in primary Triassic sequences as well as Palaeogene palaeomagnetic overprint data from the Tethyan Himalaya: rotations of the Tethyan Himalaya compared with cratonic India are thus probably all of post late Eocene age. Triassic and Early Ordovician data do not imply any crustal shortening between Tethyan Himalaya and cratonic India. However, in the Early Ordovician, India was rotated 90° compared with its present orientation, and any enlargement of India would not be detected by palaeomagnetic data.
Radiolarian age constraints on Mesotethyan ocean evolution, and their implications for development of the Bangong–Nujiang suture, Tibet
Authors: Baxter Alan T. , Aitchison Jonathan C. , Zyabrev Sergey V.
Published: June 2009

Radiolarian discoveries indicate that deep-marine conditions prevailed in central Tibet from the early Middle Jurassic until well into the Early Cretaceous (late Hauterivian–early Aptian; 131–121 Ma) and help to constrain the temporal extent of oceanic conditions along the Bangong–Nujiang suture. These new fossils occur in chert or siliceous mudstone blocks associated with the Lagkor Tso ophiolitic mélange. Basin inversion associated with closure of Mesotethys between the Qiangtang and Lhasa terranes was accompanied by mélange formation and predated regionally widespread deposition of overlying shallow-marine late Aptian–Albian orbitolinid limestones.
Stress change over short geological time: the case of Scandinavia over 9000 years since the Ice Age
Authors: Gregersen Soren , Voss Peter
Published: June 2009

Palaeoseismological investigations are used in many regions of the world to extend back in time the earthquake statistics of historical written or oral records as well as instrumental information. This is very valuable for discussions of earthquake hazard, but it only applies to areas of stable stress regime. Although the intraplate areas of Scandinavia and Greenland have experienced only rather small earthquakes within the human timescale, they serve as a clear warning on the application of palaeoseismology for hazard studies in regions where the stresses have changed.

In a small part of Scandinavia, where recent earthquake activity is not significantly different from that of its surroundings, large faults have been discovered and several have been investigated via palaeoseismology. They are interpreted to show the occurrence of large earthquakes about 9000 years ago. Signs of this are coincident landslides as well as liquefaction in loose sediments, which are well dated through varve-counting.

In contrast to this the present-day stress release in earthquakes and in surface rock deformations is mainly caused by plate motion. Regional investigations in Scandinavia and Greenland/North America, as well as those included in the World Stress Map Project of the 1990s, have shown compression within the plate, mainly in the direction of absolute plate motion. The ice cap influence has disappeared. So stress reorganization is clearly indicated over the short geological timespan of 9000 years. Into this argument goes the observation from Greenland and Antarctica, that no earthquakes occur under the ice caps. For Scandinavia the argument is that no earthquakes occurred under the ice sheet during the Ice Age, and that the stored stresses were released when the ice sheet melted 9000 years ago. This does emphasize a warning. There are regions of the globe where palaeoseismological investigations can give a fantastic extension of the short-term historical earthquake records. But in some regions stress reorganization has changed this condition.
Late Holocene earthquake geology in Sweden
Authors: Mörner Nils-Axel
Published: June 2009

As a function of the rapid rate of glacial isostatic uplift, deglacial palaeoseismicity in Sweden was exceptionally high, in magnitude as well as frequency. Today, seismic activity is low to moderately low with occasional events reaching M 4–5. In the Late Holocene, 11 events in the order of M 6–7 are recorded. These palaeoseismic events seem also to be recorded in several old place names, as in the tale of the Fenris Wolf. Some of the events generated local to regional tsunamis. The palaeoseismic activity recorded in Late Holocene time implies that our short-term seismic hazard assessment must include the possibility of future events in the order of up to M 7. For long-term hazard assessment, repeating glacial/deglacial phases, we must work with magnitudes of M 8 to 9.
Testing a seismic scenario for the damage of the Neolithic wooden well of Erkelenz-Kückhoven, Germany
Authors: Hinzen Klaus-G. , Weiner Jürgen
Published: June 2009

A Neolithic wooden well was discovered and excavated between 1989 and 1992 near Erkelenz in the Lower Rhine Embayment. The construction, 3×3 m in size and 13 m deep, was exceptionally large for its time. The larger outer box-frame contained two smaller frames whose construction could be interpreted as an attempt to repair the damaged original well. The outer box was made from 160 oak elements of about 3 m length built in the blockhouse method. The large box is dated to 5090
bc
and the two smaller ones to 5057±5
bc
by dendrochronological analysis. At
c
. 8 m depth several elements of the large box are vertically sheared off and the broken parts moved inward and downward. The cause of this damage has not yet been determined. As the well is located only 3 km from one of the active tectonic faults in the Lower Rhine Embayment, a seismogenic origin of the damage is considered and tested in this paper. This question has relevance for determination of seismic hazard in an area with present-day moderate seismicity but documented occurrence of strong surface-rupturing earthquakes from the palaeoseismic record. First, a geotechnical model for the construction pit with a total volume of
c
. 540–550 m
3
is used to prove the stability of the open pit during well construction and to help explain how the well was built. The seismogenic hypothesis is tested in a deterministic approach using theoretically derived ground motion at the site of the well for two simulated earthquakes with magnitudes 6.2 and 6.8. Ground deformation and relative displacement calculated with a finite element model of the casing are found to be too small to account for the documented damage. Among other potential sources of damage, swelling, shrinking or rotting of the wood elements are possible explanations; however, a conclusive answer to this question remains to be found.
Earthquake intensity assessment based on environmental effects: principles and case studies
Authors: Tatevossian R. E. , Rogozhin E. A. , Arefiev S. S. , Ovsyuchenko A. N.
Published: June 2009

The comparison of intensity assessments based on macroseismic data and Earthquake Environmental Effects (EEE) is presented. Specific problems faced when assessing intensities using different types of scales are discussed. Two case studies of recent earthquakes with magnitudes M
S
=7.4 (Altai, 2003, and Neftegorsk, 1995) are used to illustrate the applicability of the INQUA EEE scale. The Altai earthquake was accompanied by surface faulting of
c.
70 km length and up to 2 m of horizontal and 70 cm of vertical offset; secondary EEE were observed over 3000 km
2
. The dominant type of surface faulting during the Neftegorsk earthquake was strike-slip. The length of surface faulting was up to 46 km, maximum horizontal offset was 8.1 m, and average offset coherent with seismic moment was 3.9 m; secondary EEE were observed occasionally at considerable distance from the epicentre on wet seashore sands. Application of the INQUA scale shows the epicentral intensity of the Altai earthquake to be X degrees. Most consistent with all types of data (rupture length, maximum and average offsets) intensity assessment for the Neftegorsk earthquake which is within the X–XI degree range. Taking into account environmental effects in intensity scales is an essential requirement: it follows from the complex nature of an earthquake impact, which spans a very broad frequency range, including static deformations. The case studies illustrate that the intensity assessment of an earthquake, based only on damage to buildings, will be essentially incomplete.
Ground effects of the 18 October 1992, Murindo earthquake (NW Colombia), using the Environmental Seismic Intensity Scale (ESI 2007) for the assessment of intensity
Authors: Mosquera-Machado S. , Lalinde-Pulido C. , Salcedo-Hurtado E. , Michetti A. M.
Published: June 2009

The macroseismic intensity of the 18 October 1992 Murindo-Atrato earthquake that affected the northwestern states of Colombia (Chocó and Antioquia) is reassessed using the newly developed INQUA Environmental Seismic Intensity Scale (ESI 2007) which is based on the evaluation of earthquake environmental effects. To generate the ESI 2007 isoseismal map of northwestern Colombia, a geographical information system was used. Unifying the available information on the seismological and active tectonics framework including historical seismicity, hypocentral depths, foreshocks, aftershocks, focal mechanism, macroseismic data under the same GIS and the map of Quaternary faults allowed us to reinterpret the geological and environmental effects of the 1992 earthquakes sequence. A total of 24 sites from the areas of Quibdó, Bojayá, Rio Sucio, Murindo, Vigía del Fuerte and Turbo were evaluated. A systematic comparison among evaluated intensities (Modified Mercalli and ESI scale) revealed differences from one to two degrees. According to the ESI 2007 scale, the epicentral intensity I
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is XI. This represents one degree higher than the epicentral intensity obtained using MM and Medveded Sponhauer Karnik (MSK) intensity scales, probably due to the lack of suitable observations on building damage in this poorly populated and developed region. This information is also useful in order to shed some light on the persistent question of the exact location and dimension of the main rupture zone associated with the earthquake. The isoseismal map derived from the integration of the whole set of environmental effects with other macroseismic data strongly suggests that the causative tectonic structure is the Murindo fault. However, the rupture length derived from the distribution of ground effects is greater than the Murindo fault length, implying that other nearby fault segments were activated during the 1992 event. The new isoseismal map resulting from this work is relevant for the assessment of future seismic risk in the northwestern region of Colombia. Overall, the application of the ESI 2007 scale to the 18 October 1992 earthquake, and to similar strong events in the region, can be useful for disaster management and planning, estimation of damage, and post-earthquake recovery efforts.
Social Preferences: Some Thoughts from the Field
Authors: List John A.
Published: June 2009

This review steps back from the burgeoning economics literature on measuring social preferences and considers more carefully the empirical evidence from the lab and the field. I place the claims from the ardent supporters of the literature into three bins: one for claims that are supported by the data upon closer scrutiny, one for claims that are not supported by the data upon closer scrutiny, and one for claims that may or may not be true. The third set of claims highlights important theoretical and empirical investigations that need to be done to further our understanding of the nature and import of social preferences.
Self-Regulation at Work
Authors: Lord Robert G. , Diefendorff James M. , Schmidt Aaron M. , Hall Rosalie J.
Published: June 2009

Self-regulation at work is conceived in terms of within-person processes that occur over time. These processes are proposed to occur within a hierarchical framework of negative feedback systems that operate at different levels of abstraction and with different time cycles. Negative feedback systems respond to discrepancies in a manner that reduces deviations from standards (i.e., goals). This is in contrast to positive feedback systems in which discrepancies are created, which can lead to instability. We organize our discussion around four hierarchical levels—self, achievement task, lower-level task action, and knowledge/working memory. We theorize that these levels are loosely connected by multiple constraints and that both automatic and more conscious processes are essential to self-regulation. Within- and cross-level affective and cognitive processes interact within this system to motivate goal-related behaviors while also accessing needed knowledge and protecting current intentions from interference. Complications common in the work setting (as well as other complex, real-life settings) such as the simultaneous pursuit of multiple goals, the importance of knowledge access and expertise, and team and multiperson processes are also discussed. Finally, we highlight the usefulness of newer research methodologies and data-analytic techniques for examining such hierarchical, dynamic, within-person processes.
Personality Development: Continuity and Change Over the Life Course
Authors: McAdams Dan P. , Olson Bradley D.
Published: June 2009

The development of personality across the human life course may be observed from three different standpoints: the person as actor (behaving), agent (striving), and author (narrating). Evident even in infancy, broad differences in social action patterns foreshadow the long-term developmental elaboration of early temperament into adult dispositional traits. Research on personal strivings and other motivational constructs provides a second perspective on personality, one that becomes psychologically salient in childhood with the consolidation of an agentic self and the articulation of more-or-less stable goals. Layered over traits and goals, internalized life stories begin to emerge in adolescence and young adulthood, as the person authors a narrative identity to make meaning out of life. The review traces the development of traits, goals, and life stories from infancy through late adulthood and ends by considering their interplay at five developmental milestones: age 2, the transition to adolescence, emerging adulthood, midlife, and old age.
Sensitivity and specificity of pulse detection using a new deconvolution method
Authors: Liu Peter Y. , Keenan Daniel M. , Kok Petra , Padmanabhan Vasantha , O'Byrne Kevin T. , Veldhuis Johannes D.
Published: June 2009

Quantifying pulsatile secretion from serial hormone concentration measurements (deconvolution analysis) requires automated, objective, and accurate detection of pulse times to ensure valid estimation of secretion and elimination parameters. Lack of validated pulse identification constitutes a major deficiency in the deconvolution field, because individual pulse size and number reflect regulated processes that are critical for the function and response of secretory glands. To evaluate deconvolution pulse detection accuracy, four empirical models of true-positive markers of pituitary (LH) pulses were used. 1) Sprague-Dawley rats had recordings of hypothalamic arcuate nucleus multiunit electrical activity, 2) ovariectomized ewes underwent sampling of hypothalamo-pituitary gonadotropin-releasing hormone (GnRH pulses), 3) healthy young men were infused with trains of biosynthetic LH pulses after GnRH receptor blockade, and 4) computer simulations of pulsatile LH profiles were constructed. Outcomes comprised sensitivity, specificity, and receiver-operating characteristic curves. Sensitivity and specificity were 0.93 and 0.97, respectively, for combined empirical data in the rat, sheep, and human ( n = 156 pulses) and 0.94 and 0.92, respectively, for computer simulations ( n = 1,632 pulses). For simulated data, pulse-set selection by the Akaike information criterion yielded slightly higher sensitivity than by the Bayesian information criterion, and the reverse was true for specificity. False-positive errors occurred primarily at low-pulse amplitude, and false-negative errors occurred principally with close pulse proximity. Random variability (noise), sparse sampling, and rapid pulse frequency reduced pulse detection sensitivity more than specificity. We conclude that an objective automated pulse detection deconvolution procedure has high sensitivity and specificity, thus offering a platform for quantitative neuroendocrine analyses.
Functional significance of skeletal muscle adiponectin production, changes in animal models of obesity and diabetes, and regulation by rosiglitazone treatment
Authors: Liu Ying , Chewchuk Simon , Lavigne Charles , Brûlé Sophie , Pilon Genevieve , Houde Vanessa , Xu Aimin , Marette Andre , Sweeney Gary
Published: June 2009

Endocrine effects of adipose-derived adiponectin on skeletal muscle have been shown to account, at least in part, for the anti-diabetic effects of this adipokine. Recently, the concept of myokines has gained credence, and the potential for skeletal muscle to produce adiponectin has been suggested. Here we demonstrated an increased level of adiponectin mRNA and protein expression as well as protein secretion in response to rosiglitazone treatment in L6 muscle cells. This correlated with the ability of rosiglitazone to enhance insulin sensitivity for stimulation of protein kinase B (Akt) phosphorylation and glucose transport; rosiglitazone also corrected high-glucose-induced insulin resistance in L6 cells. Overexpression of adiponectin confirmed the functional significance of local production of adiponectin in muscle cells via elevated glucose uptake and increased insulin sensitivity. In obese diabetic db/db mice, there was a change in the adiponectin expression profile in soleus and extensor digitorum longus (EDL) muscle with less high molecular weight (HMW) and more medium (MMW)/low (LMW) molecular weight species detected. Induction of obesity and insulin resistance in rats by feeding a high-fat high-sucrose diet also led to decreased muscle HMW adiponectin content that could be corrected by rosiglitazone treatment. In summary, we show the ability of skeletal muscle cells to produce adiponectin, which can mediate autocrine metabolic effects, thus establishing adiponectin as a bona fide myokine. We also demonstrate that skeletal muscle adiponectin production is altered in animal models of obesity and diabetes and that these changes can be corrected by rosiglitazone.
Frontiers: PED/PEA-15, a multifunctional protein controlling cell survival and glucose metabolism
Authors: Fiory Francesca , Formisano Pietro , Perruolo Giuseppe , Beguinot Francesco
Published: June 2009

PED/PEA-15 is a 15-kDa ubiquitously expressed protein implicated in a number of fundamental cellular functions, including apoptosis, proliferation, and glucose metabolism. PED/PEA-15 lacks enzymatic function and serves mainly as a molecular adaptor. PED/PEA-15 is an endogenous substrate for protein kinase C (PKC), calcium/calmodulin-dependent protein kinase II (CAM kinase II), and Akt. In particular, PKC phosphorylates PED/PEA-15 at Ser104and CAM kinase II or Akt at Ser116, modifying its stability. Evidence obtained over the past 10 years has indicated that PED/PEA-15 regulates cell survival by interfering with both intrinsic and extrinsic apoptotic pathways. In addition, it may also control cell proliferation by interfering with ERK1/2-mediated pathways. Indeed, PED/PEA-15 has been identified as an ERK1/2 interactor, which modifies its subcellular localization and targeting to a specific subset of substrates. Increased PED/PEA-15 levels may affect tumorigenesis and cancer progression as well as sensitivity to anticancer agents. Moreover, PED/PEA-15 affects astrocyte motility and increases susceptibility to skin carcinogenesis in vivo. PED/PEA-15 expression is regulated at the transcriptional and the posttranslational levels. Increased PED/PEA-15 expression has been identified in individuals with type 2 diabetes early during the natural history of the disease. Evidence generated over the past 10 years indicated that this defect contributes to altering glucose tolerance by impairing insulin action and insulin secretion and might play a role in the development of diabetes-associated neurological disorders. Strategies are being devised to target key signaling events in PED/PEA-15 action aimed at improving glucose tolerance and at facilitating cancer cell death.
Sonic hedgehog improves delayed wound healing via enhancing cutaneous nitric oxide function in diabetes
Authors: Luo Jian-Dong , Hu Tai-Ping , Wang Li , Chen Min-Sheng , Liu Shi-Ming , Chen Alex F.
Published: June 2009

Sonic hedgehog (SHH) plays an important role in postnatal tissue repair. The present study tested the hypothesis that impaired SHH pathway results in delayed wound healing by suppressing cutaneous nitric oxide (NO) function in type 1 diabetes. Adult male C57/B6 mice and streptozotocin (STZ)-induced type 1 diabetic mice were used. Although cutaneous SHH and Patched-1 (Ptc-1 encoded by PTCH, PTCH 1) proteins were increased significantly on day 4 after wounding compared with day 0 in normal mice, both were decreased significantly in STZ-induced diabetic mice. Topical application of SHH restored wound healing delay in STZ-induced diabetic mice, with a concomitant augmentation of both cutaneous constitutive nitric oxide synthase (NOS) activity and nitrite level. The effects of SHH on wound healing and cutaneous NO function were markedly inhibited by SHH receptor inhibitor cyclopamine. After 24-h treatment in vitro, SHH (5–20 μg/ml) significantly increased cutaneous endothelial NOS protein expression, NOS activity and NO level in normal mice and STZ-induced diabetic mice in a concentration-dependent manner, an effect that was blunted by cyclopamine and NOS inhibitor Nω-nitro-l-arginine methyl ester. The phosphatidylinositol 3-kinase inhibitor LY-294002 significantly blunted the increase of NOS activity and NO level induced by SHH treatment in human umbilican vein endothelial cells. These results demonstrate that the SHH pathway is activated in a normal wound, and its reduction results in impaired NO function and wound healing in diabetes. Strategies aimed at augmenting the endogenous SHH pathway may provide an effective means in ameliorating delayed diabetic wound healing.