bluuebunny/crossref_metadata_2025 huggingface dataset:
Structure of fast shocks in the presence of heat conduction
Authors: Tsai C. L. , Chen H. H. , Wu B. H. , Lee L. C.
Published: December 2007

There are three types of magnetohydrodynamic (MHD) shocks: the fast shock, intermediate shock, and slow shock. The structure of slow shocks and intermediate shocks in the presence of heat conduction has been studied earlier [C. L. Tsai, R. H. Tsai, B. H. Wu, and L. C. Lee, Phys. Plasmas 9, 1185 (2002); C. L. Tsai, B. H. Wu, and L. C. Lee, Phys. Plasmas 12, 82501 (2005)]. Based on one-dimensional MHD numerical simulations with a heat conduction term, the evolution and structure of fast shocks are studied. The fast shock will form a foreshock in the presence of heat conduction. The foreshock is formed due to the heat flow from downstream to upstream and located in the immediate upstream of the main shock. In the steady state, the value of diffusion velocity Vd in the foreshock is found to nearly equal the upstream convection velocity in the fast shock frame. It is found that the density jump across the main shock in high Mach number case can be much larger than 4 in the early simulation time. However the density jump will gradually evolve to a value smaller than 4 at steady state. By using the modified Rankine-Hugoniot relations with heat flux, the density jump across the fast shock is examined for various upstream parameters. The results show that the calculated density jump with heat flux is very close to the simulation value and the density jump can far exceed the maximum value of 4 without heat conduction. The structure of foreshock and main shock is also studied under different plasma parameters, such as the heat conductivity K0, the ratio of upstream plasma pressure to magnetic pressure β1, Alfvén Mach number MA1, and the angle θ1 between shock normal and magnetic field. It is found that as the upstream shock parameters K0, β1, and MA1 increase or θ1 decreases, the width of foreshock Ld increases. The present results can be applied to fast shocks in the solar corona, solar wind, and magnetosphere, in which the heat conduction effects are important.
An approach for researching uniaxial anisotropy magnet: Rotational magnetization
Authors: Fan Xiaolong , Xue Desheng , Jiang Changjun , Gong Yu , Li Jinyun
Published: December 2007

In this study, rotational magnetization curves are used to investigate the anisotropy and the rotational magnetization process of uniaxial magnets. We measured the projection of magnetization as a function of angle between the magnetic field and the reference axis. The information about anisotropy, such as the directions of the easy axis and hard axis, as well as the anisotropy field Hk(i), is acquired. Simultaneously, the rotational magnetization reversal processes are derived. The Co and Fe28Co61Zr11 magnetic thin films with induced in-plane uniaxial anisotropy have been researched. We found that the rotational magnetization reversal process of the Co film is a coherent rotation. However, the Fe28Co61Zr11 film shows the similar behavior, except for a noncoherent rotation appearing when a small field parallels the hard axis.
Fabrication of epitaxial CrO2 nanostructures directly on MgO(100) by pulsed laser deposition
Authors: Heinig N. F. , Jalili H. , Leung K. T.
Published: December 2007

Single-phase CrO2 nanostructured thin films have been grown directly on MgO(100) by pulsed laser ablation of a metallic Cr target in an O2 environment. X-ray diffraction shows that these films are strained and consist of CrO2 crystallites with two possible epitaxial relationships to the substrate; either CrO2(110) or CrO2(200) is parallel to MgO(100). Scanning electron microscopy and atomic force microscopy reveal orthogonally arranged nanoneedles and platelike structures (both 30–50nm thick). X-ray photoemission confirms that the films are primarily CrO2 covered with a thin CrO3 overlayer and indicates its complete synthesis without any residual metallic Cr.
A mechanism for unipolar resistance switching in oxide nonvolatile memory devices
Authors: Sánchez M. J. , Rozenberg M. J. , Inoue I. H.
Published: December 2007

We propose a mechanism for unipolar resistance switching in metal-insulator-metal sandwich structures. The commutation from the high to low resistance state and back can be achieved with successive voltage sweeps of the same polarity. Electronic correlation effects at the metal-insulator interface are found to play a key role to produce a resistive commutation effect in qualitative agreement with recent experimental reports on binary transition metal oxide based sandwich structures.
Interval percolation and ceramic-metal composite
Authors: Cheng Yonghong , Wu Kai , Chen Xiaolin , Chen Yu , Meng Yongpeng
Published: December 2007

The mixture of the BaTiO3 ceramic powder and silver ink was baked, and the bulk property of positive temperature coefficient (PTC) of BaTiO3 was recovered in the composite. An interval percolation model was put forward to describe this composite. Monte-Carlo simulation confirmed that the bulk property can be surely recovered in a cubic network if the fraction of conductive sites is in the range of 0.101–0.311. Moreover, experimental works indicated that the percolation threshold decreased with the increase of the size of ceramic particles, and the PTC bulk property appeared more obviously at higher electrical field.
Electrical signal amplification of DNA hybridization by nanoparticles in a nanoscale gap
Authors: Chen Chun-Chi , Ko Fu-Hsiang , Chen Chieh-Tso , Liu Tzeng-Feng , Chang Edward Yi , Yang Yu-Hsiung , Yan Su-Jan , Chu Tieh-Chi
Published: December 2007

We report two different methods to electrically sense deoxyribonucleic acid (DNA) hybridization and suggest that nanoparticles can act as hopping sites that amplify the conductance of the hybridized DNA strand. Single-stranded DNA has no amplification effect on conductance, but hybridized double-stranded DNA tethered to 10nm gold nanoparticles exhibits a 30-fold amplification of conductance. As to the aldehyde-derived target DNA method, silver nanoparticles from silver ion reduction in the 70nm nanogap enhance the conductance signal by 106.
Self-assembling surface stress domains far from equilibrium
Authors: Medhekar N. V. , Shenoy V. B. , Hannon J. B. , Tromp R. M.
Published: December 2007

We have used real-time low-energy electron microscopy to observe the growth and shape evolutions of self-assembled stress domains on Si(111) surfaces. We find that elastic strain leads to dramatic transformations in the shapes of large domains that are not predicted by existing theoretical models. By comparing the experimental observations on the formation of the stress domains with dynamic growth simulations, we have developed a quantitative understanding of how a self-assembling system falls out of equilibrium. Our work shows the nonequilibrium shapes that a domain adopts during growth depending very strongly on the azimuthal dependence of its boundary energy.
Enzymatic glucose detection using ZnO nanorods on the gate region of AlGaN∕GaN high electron mobility transistors
Authors: Kang B. S. , Wang H. T. , Ren F. , Pearton S. J. , Morey T. E. , Dennis D. M. , Johnson J. W. , Rajagopal P. , Roberts J. C. , Piner E. L. , Linthicum K. J.
Published: December 2007

ZnO nanorod-gated AlGaN∕GaN high electron mobility transistors (HEMTs) are demonstrated for the detection of glucose. A ZnO nanorod array was selectively grown on the gate area using low temperature hydrothermal decomposition to immobilize glucose oxidase (GOx). The one-dimensional ZnO nanorods provide a large effective surface area with high surface-to-volume ratio and provide a favorable environment for the immobilization of GOx. The AlGaN∕GaN HEMT drain-source current showed a rapid response of less than 5s when target glucose in a buffer with a pH value of 7.4 was added to the GOx immobilized on the ZnO nanorod surface. We could detect a wide range of concentrations from 0.5nMto125μM. The sensor exhibited a linear range from 0.5nMto14.5μM and an experiment limit of detection of 0.5nM. This demonstrates the possibility of using AlGaN∕GaN HEMTs for noninvasive exhaled breath condensate based glucose detection of diabetic application.
Correlation of important seedling traits in cauliflower varieties and potential association with RAPD markers
Authors: Astarini Ida A. , Plummer Julie A. , Lancaster Rachel A. , Yan Guijun
Published: December 2007

Cauliflower production is hindered by variation in curd quality and maturity. Morphological variation from seed to harvest is due to genetic variation interacting with environmental conditions and here the genetic factors were investigated. The aim of this study was to search for DNA markers linked to seedling traits, facilitating early selection of seedlings in cauliflower production. Cauliflower seed lines were germinated in Petri dishes (20°C, 7 days) and seedlings were transferred to pots and grown under glasshouse conditions. Seed weight and various seedling characters were measured until harvest at 6 weeks. DNA was extracted using the CTAB method and RAPD markers were identified using 17 primers. Multivariate analysis based on principal coordinates analysis was used to correlate morphological traits with molecular markers across cultivars. Markers associated with seed weight, germination rate, shoot length, root length, fresh weight, and dry weight were identified.
Assessment of molecular diversity in landraces of bread wheat (Triticum aestivum L.) held in an ex situ collection with Diversity Arrays Technology (DArT™)
Authors: Stodart B. J. , Mackay M. C. , Raman H.
Published: December 2007

Diversity Arrays Technology (DArT™) was evaluated as a tool for determining molecular diversity of wheat landraces held within the Australian Winter Cereals Collection (AWCC). Initially, a set of 44 wheat landraces was evaluated with 256 DArT markers. The dataset was compared with the results obtained using 16 amplified fragment length polymorphism (AFLP) primer combinations and 63 simple sequence repeat (SSR) markers, mapped on the 21 chromosomes, from a previous study. The DArT markers exhibited a strong positive correlation with AFLP and SSR, with each marker type distinguishing similar relationships among the 44 landrace accessions. The DArT markers exhibited a higher polymorphic information content than AFLP, and were comparable with that obtained with SSR. Three hundred and fifty-five DArT markers were then used to evaluate genetic diversity among 705 wheat landrace accessions from within the AWCC, chosen to represent 5 world regions. DArT analysis was capable of distinguishing accessions from different geographic regions, and suggested that accessions originating from Nepal represent a unique gene pool within the collection. A statistical resampling of DArT loci indicated that 10–20 loci were enough to distinguish the maximum molecular diversity present within the collection. This research demonstrates the efficacy of the DArT platform as a tool for efficient examination of wheat diversity. As an ex situ germplasm repository, the AWCC contains wheat accessions of high genetic diversity, from genetically differentiated collection sites, even though diversity was under-represented in some countries represented in the repository.
Water use by annual crops. 1. Role of dry matter production
Authors: Ward P. R. , Hall D. J. M. , Micin S. F. , Whisson K. , Willis T. M. , Treble K. , Tennant D.
Published: December 2007

In southern Australia, expanding dryland salinity is the result of increased deep drainage associated with widespread replacement of native perennial vegetation by annual agricultural crops and pastures. Although perennial pastures have been shown to assist in slowing salinisation, their adoption has been slow, and annual crops and pastures are likely to remain as the dominant land use for the foreseeable future. Therefore, understanding the water balance of annual crops and pastures, and how it can be manipulated, is important in trying to manage salinity. In this research we investigate the effect of varying levels of dry matter production on components of the water balance (soil evaporation, transpiration, soil water storage, and drainage) for annual crops at contrasting sites and soil types in south-western Australia. Dry matter production was controlled by fertiliser addition and crop rotation, and varied by a factor of up to 2, depending on seasonal conditions. Deep drainage was zero for most sites and years, but where it was greater than zero, there was no discernible effect due to production level. Out of a total of 14 site/year comparisons, the difference in soil water extraction associated with greater dry matter production averaged 5 mm, and was greater than 20 mm on only 1 occasion. However, high dry matter production was associated with greater transpiration, at the expense of soil evaporation. Manipulating dry matter production is unlikely to have a substantial effect on deep drainage and the expansion of dryland salinity in south-western Australia.
Roots of Australian alpine plant species contain high levels of stored carbohydrates independent of post-fire regeneration strategy
Authors: Tolsma A. D. , Read S. M. , Tolhurst K. G.
Published: December 2007

The relationships between root morphology, level of stored non-structural carbohydrates and post-fire regeneration strategy were investigated in 37 Australian alpine plant species: 6 reseeders, 14 resprouters and 17 capable of both reseeding and resprouting. High concentrations of stored carbohydrate (up to 61.8% DW) were a feature of most species, with more than half of the 37 species containing non-structural carbohydrate concentrations of more than 10%. Fructan was the major reserve polysaccharide in 32 of the 37 species, with particularly high concentrations in the Asteraceae (up to 43.1%). Herbaceous species stored higher concentrations of carbohydrates and had fleshier roots than did shrub species, but swollen underground storage organs were found in only one species (Microseris scapigera sensu Willis1, Asteraceae). There was no significant relationship between post-fire regeneration strategy and either root morphology or level of carbohydrate storage, contrasting with results from drier, Mediterranean environments. Root storage of high levels of carbohydrate, and especially fructan, in Australian alpine species could therefore result from an adaptation to the alpine environment, such as a need for annual regeneration of leaf tissue in alpine conditions.
Flowering, seed production and seed mass in a species-rich temperate grassland exposed to FACE and warming
Authors: Hovenden Mark J. , Wills Karen E. , Vander Schoor Jacqueline K. , Chaplin Rebecca E. , Williams Amity L. , Nolan Michaela J. , Newton Paul C. D.
Published: December 2007

Long-term effects of climate change on plant communities must be mediated by reproductive and recruitment responses of component species. From spring 2003 until autumn 2006, we monitored flowering and seed-production responses to free air CO2 enrichment (FACE) and 2°C warming in a species-rich, nutrient-poor southern temperate grassland, by using the TasFACE experiment. There were no effects of either FACE or warming on the proportion of species flowering in any year. Flowering, seed production and seed mass were not significantly affected by FACE, warming or their interaction in most species. Some species, however, did respond significantly to simulated global changes. These responses generally were not governed by life history, but there were two distinct trends. First, warming increased the proportion of the population that flowered in perennial grasses but not in other species types. Second, flowering and seed production of both perennial woody dicots responded strongly to the interaction of FACE and warming, with Bossiaea prostrata producing most seeds in warmed FACE plots and Hibbertia hirsuta producing the most in unwarmed FACE plots. FACE increased seed mass 4-fold in the perennial C3 grass Elymus scaber (P < 0.01) but substantially reduced seed mass of the perennial C3 grass Austrodanthonia caespitosa (P < 0.02) and the perennial forb Hypochaeris radicata (P < 0.02), with the remainder of species unaffected. Our results indicate that warming and elevated CO2 had little effect on seed production in the temperate grassland ecosystem. The few significant affects there were, however, are likely to have substantial implications for community composition and structure.
Factors in United States Forest Service district rangers' decision to manage a fire for resource benefit
Authors: Williamson Martha A.
Published: December 2007

United States wildland fire policy and program reviews in 1995 and 2000 required both the reduction of hazardous fuel and recognition of fire as a natural process. Despite the fact that existing policy permits managing natural ignitions to meet resource benefits, or Wildland Fire Use (WFU), most fuel reduction projects rely on mechanical treatments and prescribed fire. Budget constraints suggest that successful fuel and ecosystem management hinges on expanding WFU. The decision to authorise WFU in the US Department of Agriculture Forest Service (USFS) rests with line officers, and the so-called ‘go/no go’ decision constitutes a time-critical risk assessment. Factors influencing this decision clearly impact the viability of WFU. The present study examined influences on line officers’ go/no go decision. A telephone survey was conducted of all USFS district rangers with WFU authority in the Northern, Intermountain, and Southwestern Regions. The census was completed during February 2005 and obtained an 85% response rate. Data were analysed using Classification and Regression Tree analysis. Personal commitment to WFU provided the primary classifier for 91% of the district rangers who authorised WFU. External factors, negative public perception, resource availability, and a perceived lack of support from the USFS were the main disincentives to authorising WFU.
Predicting sustained smouldering combustion in trembling aspen duff in Elk Island National Park, Canada
Authors: Otway S. G. , Bork E. W. , Anderson K. R. , Alexander M. E.
Published: December 2007

Fire is one of the key disturbances affecting trembling aspen (Populus tremuloides Michx.) forest ecosystems within western Canadian wildlands, including Elk Island National Park in central Alberta, Canada. Although prescribed fire is a tool available to modify aspen forests, a clear understanding of its potential impact is necessary to successfully manage this disturbance. Undesirable social and ecological consequences of severe, deep-burning ground fires include smoke generation and impaired vegetation regrowth. Data on the duff moisture conditions under which ground or subsurface fires may ignite and spread in aspen forest duff layers are presented, as well as experimental test fire results. Different topographic positions, plant communities and seasonality were factored into the research design. The Duff Moisture Code (DMC) and Drought Code (DC) components of the Canadian Forest Fire Weather Index System were calculated and factors including duff moisture content, bulk density and inorganic content measured before ignition of experimental test fires. Probability of sustained smouldering combustion models were developed for the duff layer in the aspen forest fuel type in Elk Island National Park, with values of 27 for DMC and 300 for DC at the 50% probability level.
Modelling emissions from Canadian wildfires: a case study of the 2002 Quebec fires
Authors: Lavoué David , Gong Sunling , Stocks Brian J.
Published: December 2007

The present paper proposes an original approach to estimate gaseous and particulate emissions from boreal forest fires based on the Canadian Forest Fire Behaviour Prediction (FBP) System. The FBP System permits calculation of fuel consumption and rate of spread for individual fires on an hourly basis from meteorological conditions and fuel patterns. Weather data are obtained by running the Canadian weather forecast model GEM (Global Environmental Multiscale). Hourly emission point sources can then be generated from a given wildfire database. The smoke emission model was first applied to the boreal forest fires in Quebec in the summer of 2002. Geographical distribution and temporal variability of emission amounts, as well as injection heights, were assessed hourly. In July, ~150 wildfires released 39 Mt of CO2 equivalent of greenhouse gases and 470 kt of fine particulate matter to the atmosphere. They contributed 32 and 5% of Quebec’s and Canada’s annual greenhouse gas emissions, respectively. Black carbon was estimated to account for 4% of the total fine particulate matter. Wildfires were responsible for 51 and 90% of all Canada’s black carbon and particulate organic matter sources, respectively.
Gilbert Weidinger: Regeneration researcher
Authors: Williams Ruth
Published: December 2007

Weidinger wants to grow new limbs and organs.
The mitochondrial respiratory chain is a modulator of apoptosis
Authors: Kwong Jennifer Q. , Henning Matthew S. , Starkov Anatoly A. , Manfredi Giovanni
Published: December 2007

Mitochondrial dysfunction and dysregulation of apoptosis are implicated in many diseases such as cancer and neurodegeneration. We investigate here the role of respiratory chain (RC) dysfunction in apoptosis, using mitochondrial DNA mutations as genetic models. Although some mutations eliminate the entire RC, others target specific complexes, resulting in either decreased or complete loss of electron flux, which leads to impaired respiration and adenosine triphosphate (ATP) synthesis. Despite these similarities, significant differences in responses to apoptotic stimuli emerge. Cells lacking RC are protected against both mitochondrial- and endoplasmic reticulum (ER) stress–induced apoptosis. Cells with RC, but unable to generate electron flux, are protected against mitochondrial apoptosis, although they have increased sensitivity to ER stress. Finally, cells with a partial reduction in electron flux have increased apoptosis under both conditions. Our results show that the RC modulates apoptosis in a context-dependent manner independent of ATP production and that apoptotic responses are the result of the interplay between mitochondrial functional state and environmental cues.
The Onset of Convection in a Porous Medium Occupying an Enclosure of Variable Width or Height
Authors: Nield D. A. , Kuznetsov A. V.
Published: December 2007

An analytical study is made of the onset of convection in a saturated porous medium occupying a two-dimensional enclosure of uniform height, but whose width is slowly varying in an arbitrary manner, or one of uniform width, but whose height is slowly varying in an arbitrary manner. It is found that the variation of width generally has a stabilizing effect, whereas variation of height generally has a destabilizing effect.
NOISE OF AN ACOUSTO-OPTIC MODULATOR AND LIMITATIONS OF AN OPTO-ELECTRONIC LOOP FOR LASER BEAM INTENSITY STABILIZATION
Authors: TETCHEWO GUILENE , DU BURCK FREDERIC , DJELLALI NADIA , LAISSOUB CHARAF
Published: December 2007

The possibilities of beam intensity noise rejection offered by a narrow-band closed opto-electronic loop system are studied. The noise added to the beam by the acousto-optic modulator used as the actuator is computed. The intensity noise of the in-loop beam can be found below the standard quantum limit but the extracted beam noise is always above this limit. For an input beam with a small excess noise, an increase of the noise can be observed. A simple model of the loop based on the noise transfer functions approach is used for the calculation of the noise power of beam intensities and photocurrents. The behavior of the system and the limitations of noise rejection are analyzed.
CHARACTERIZATION OF NONSTATIONARY ATOMIC CLOCKS
Authors: GALLEANI LORENZO , TAVELLA PATRIZIA
Published: December 2007

Atomic clocks are the core of a navigation system. Since an error in time results in an error in the user localization, it is fundamental that the stability is very high and constant with time. In this paper we discuss the dynamic Allan variance, or DAVAR, a representation of the time-varying stability of an atomic clock. We show by simulation its effectiveness in tracking common nonstationary behaviors of a clock.
A Sturzstrom-like cliff fall on the Chalk coast of Sussex, UK
Authors: Williams R. B. G. , Robinson D. A. , Dornbusch U. , Foote Y. L. M. , Moses C. A. , Saddleton P. R.
Published: December 2007

In 1914 a notable cliff fall occurred on the chalk coast of the Seven Sisters in Sussex. Debris from the fall travelled outwards across the shore platform in front of the cliff for a distance of about 75 m, forming a narrow tongue-like projection. The reason why the debris exhibited such mobility is uncertain, but it may have flowed in a similar fashion to a sturzstrom, despite its modest volume (c. 12500m
3
) and the equally modest height of the cliff (44–45 m). If this suggestion is correct, the minimum volume of detached rock required to trigger sturzstrom-type flow is 1–2 orders of magnitude less than is commonly claimed.
The propagation of wave impact induced pressures into cracks and fissures
Authors: Wolters G. , Müller G.
Published: December 2007

Rock cliffs and blockwork coastal structures often suffer a peculiar type of damage, whereby individual blocks are removed out of their location towards the sea. The location of damage suggests that breaking wave action is the main cause. It has been suggested that wave impact pressures travel into the water or air filled cracks and fissures of the structures, leading to large pressures acting inside of the structure or cliff and to the removal of blocks. This assumption was only recently confirmed for water filled cracks with a series of model tests at Queen's University Belfast. Real cracks in rock cliffs are, however, often only partially filled with water. A new experimental study, also conducted at Queen's University Belfast, revealed that wave impact generated pressures can ravel into both fully or partially water filled cracks or joints. In partially submerged cracks the pressure pulse was found to travel in the air, propagating fast and with little attenuation deep into the structure, signifying that partially filled cracks are potentially more dangerous for the integrity of the structure than completely water filled cracks. These pressure pulses may be the main cause for the
seaward
removal of blockwork in coastal engineering structures or of rock cliff material.
Coastal cliff erosion vulnerability on the Canadian east coast (Baie des Chaleurs area): a multi-parameter visualization tool
Authors: Daigneault M. , Bouchardon J-L. , Guy B.
Published: December 2007

In order to assess a cliff&rss vulnerability to erosion, researchers must consider a number of parameters that collectively account for all possible erosional processes. The authors have developed a radial diagram that allows the most active processes of erosion to be visualized (e.g. hydrodynamic, gravity-driven or atmospheric), and when such diagrams are presented on a map, they can be used to rapidly identify the contributing erosional processes at a given location. The diagram, developed for the Baie des Chaleurs region (eastern coast of Canada), displays numerical values that represent the relative importance of various weakening parameters for a set of cliffs. In addition, a colour code represents the dominant lithology, and the diagram diameter is a function of the erosion rate. The data for each diagram are based on field observations, experimental work and results of mineralogical and petrophysical analyses. Ten fundamental parameters were used to assess the structural, petrophysical and environmental processes of erosion: porosity, percentage of matrix or cement, homogeneity of the stratification, presence of schistosity, fracture density, number of fracture sets, presence of faults, dip of the strata, effect of waves, and the presence of groundwater. Coastal managers can use these diagrams in conjunction with natural risk maps to estimate the vulnerability of a cliff and decide whether engineering structures are required for preservation.
Observations from the Alpine Tethys and Iberia–Newfoundland margins pertinent to the interpretation of continental breakup
Authors: Manatschal G. , Müntener O. , Lavier L. L. , Minshull T. A. , Péron-Pinvidic G.
Published: December 2007

Although the Iberia–Newfoundland and Alpine Tethys margins are of different age and ultimately had a different fate, they share remarkable similarities. Both pairs of margins show a change from initially distributed and decoupled extension to later localized, coupled and asymmetric extension that results in thinning of the crust and exhumation of subcontinental mantle. The change in the mode of extension together with the localization of deformation reflects an evolution of the bulk rheology of the extending lithosphere. In this paper we summarize the pertinent geological observations for the Iberia–Newfoundland and Alpine Tethys margins. We describe the stratigraphic evolution, the fault geometry, basin architecture, and magmatic and metamophic evolution of the two pairs of margins from initial rifting to final continental breakup. This description forms a basis for understanding the evolution of the bulk rheology and how the various processes interact during progressive lithospheric extension. For the Iberia–Newfoundland and Alpine Tethys margins initial rifting appears to be controlled by inherited heterogeneities and mechanical localization processes, whereas final rifting and lithospheric rupture is controlled by serpentinization, magmatic and thermal weakening. At other margins, these modes may interact in a different way depending on the prerift conditions and the evolution of the rheology during rifting.
Continental lithospheric thinning and breakup in response to upwelling divergent mantle flow: application to the Woodlark, Newfoundland and Iberia margins
Authors: Kusznir N. J. , Karner G. D.
Published: December 2007

Depth-uniform stretching is not the dominant deformation process for thinning continental lithosphere leading to breakup; it cannot explain the observed depth-dependent lithosphere stretching and mantle exhumation at rifted continental margins. Depth-dependent lithosphere thinning, in which stretching of the lower crust and lithosphere mantle greatly exceeds that of the upper crust, has been observed at many non-volcanic and volcanic rifted continental margins including conjugate margin pairs. Passive continental margins show a paucity of brittle deformation in the upper crust during continental lithosphere thinning leading to breakup and sea-floor spreading initiation. A new model of rifted continental margin formation has been developed that assumes that deformation and thinning of continental lithosphere leading to breakup occurs in response to an upwelling divergent flow field within continental lithosphere and asthenosphere, and that this deformation evolves into sea-floor spreading. The new model successfully predicts depth-dependent stretching of continental margin lithosphere for both non-volcanic and volcanic margins and mantle exhumation at non-volcanic margins, both of which are observed, but are not explained, by existing depth-uniform continental lithosphere stretching models. The new model provides a balance of extensional strain, supplies an explanation for the paucity of synrift brittle deformation, and offers a simple transition from prebreakup lithosphere thinning to sea-floor spreading. The observed diversity of rifted continental margin structure and width of the ocean–continent transition can be explained by variability in the form of the upwelling divergent flow field. The new upwelling divergent flow model of continental lithosphere thinning leading to continental breakup successfully predicts the observed bathymetry and margin geometry for the most recent segment of sea-floor spreading initiation in the Woodlark Basin in the western Pacific, and the observed bathymetry and free air gravity anomaly for the Newfoundland and Iberian margins.
Association between Breast Density and Subsequent Breast Cancer Following Treatment for Ductal Carcinoma In situ
Authors: Hwang E. Shelley , Miglioretti Diana L. , Ballard-Barbash Rachel , Weaver Donald L. , Kerlikowske Karla ,   for the National Cancer Institute Breast Cancer Surveillance Consortium
Published: December 2007

Background: Risk of invasive cancer following treatment for ductal carcinoma in situ (DCIS) is associated with both treatment- and tumor-related factors. However, it is unknown whether stromal factors such as breast density may also influence subsequent invasive breast events. We investigated whether breast density is an independent predictor of subsequent breast events among women treated for DCIS.

Population: A prospective cohort study of 3,274 women ages 30 to 93 in the Breast Cancer Surveillance Consortium treated with lumpectomy for DCIS between 1993 and 2005. All subjects had an American College of Radiology Breast Imaging Reporting and Data System (BI-RADS) breast density measure recorded prior to diagnosis.

Methods: Ipsilateral and contralateral breast cancer following lumpectomy for DCIS were ascertained through state tumor registries, regional Surveillance Epidemiology and End Results program or pathology databases. A Cox proportional hazard model was used to compare adjusted risk of breast cancer among women with high (BI-RADS 3 or 4) versus low (BI-RADS 1 or 2) breast density.

Results: During a median follow-up period of 39 months (0-132 months), 133 women developed invasive breast cancer. After adjusting for age and radiation treatment, high breast density was associated with increased hazard for contralateral (hazard ratio, 3.1; 95% confidence interval, 1.6-6.1) but not ipsilateral (hazard ratio, 1.0; 95% confidence interval, 0.6-1.6) invasive breast events.

Conclusion: High breast density is associated with contralateral, but not ipsilateral, invasive breast cancer following lumpectomy for DCIS. Thus, women with DCIS and high breast density may especially benefit from antiestrogenic therapy to reduce the risk of contralateral invasive disease. (Cancer Epidemiol Biomarkers Prev 2007;16(12):2587–93)
Nutrients Involved in One-Carbon Metabolism and Risk of Breast Cancer among Premenopausal Women
Authors: Cho Eunyoung , Holmes Michelle , Hankinson Susan E. , Willett Walter C.
Published: December 2007

Folate, vitamin B6, vitamin B12, methionine, choline, and betaine are nutrients involved in one-carbon metabolism and have been hypothesized to reduce the risk of breast cancer. However, previous epidemiologic studies on most of these nutrients and breast cancer risk have been inconclusive and have included primarily postmenopausal women. No study has examined choline and betaine in relation to breast cancer risk. Therefore, we examined the intake of these nutrients in relation to breast cancer risk among 90,663 premenopausal women ages 26 to 46 years in 1991 in the Nurses' Health Study II. Nutrient intake was assessed with a validated food frequency questionnaire in 1991, 1995, and 1999. During 12 years of follow-up from 1991 to 2003, we documented 1,032 incident cases of invasive breast cancer. Overall, none of the nutrients was associated with risk of breast cancer. The results were similar by levels of alcohol intake and folate intake and for estrogen receptor–negative breast cancer. In conclusion, we found no evidence that higher intakes of nutrients involved in one-carbon metabolism reduce risk of breast cancer among premenopausal women. (Cancer Epidemiol Biomarkers Prev 2007;16(12):2787–90)
Pulmonary Diseases and the Heart
Authors: Han MeiLan K. , McLaughlin Vallerie V. , Criner Gerard J. , Martinez Fernando J.
Published: December 2007

The complex nature of interactions between the pulmonary and cardiovascular systems is becoming increasingly appreciated. Pulmonary vascular abnormalities are frequently present in patients with respiratory disorders, including chronic obstructive pulmonary disease, idiopathic pulmonary fibrosis, sarcoidosis, neuromuscular or chest wall disorders, and disorders of ventilatory control including sleep apnea syndromes and obesity hypoventilation syndrome. Pulmonary hypertension, classified as group III in the World Health Organization classification scheme for pulmonary hypertension, may result in severe right ventricular dysfunction caused by lung disease, also known as cor pulmonale. The development of cor pulmonale is generally associated with poorer prognosis and increased death. Systemic manifestations of lung disease, particularly obstructive disorders, are also particularly relevant because they are associated with increased cardiac death and impaired health status. This article will discuss the most common pulmonary diseases and disorders of ventilatory control that cause pulmonary vascular abnormalities and cor pulmonale, with particular concentration on how treatment of these diseases may affect the heart. In addition, the complex nature of cardiac and lung disease will also be explored, particularly with respect to the relationship between chronic obstructive pulmonary disease, systemic inflammation, atherosclerosis, and cardiovascular death, which is currently a very active focus of research.
The Diffusion Decision Model: Theory and Data for Two-Choice Decision Tasks
Authors: Ratcliff Roger , McKoon Gail
Published: December 2007

The diffusion decision model allows detailed explanations of behavior in two-choice discrimination tasks. In this article, the model is reviewed to show how it translates behavioral data—accuracy, mean response times, and response time distributions—into components of cognitive processing. Three experiments are used to illustrate experimental manipulations of three components: stimulus difficulty affects the quality of information on which a decision is based; instructions emphasizing either speed or accuracy affect the criterial amounts of information that a subject requires before initiating a response; and the relative proportions of the two stimuli affect biases in drift rate and starting point. The experiments also illustrate the strong constraints that ensure the model is empirically testable and potentially falsifiable. The broad range of applications of the model is also reviewed, including research in the domains of aging and neurophysiology.
Angkor Vogue: Sculpted Evidence of Imported Luxury Textiles in the Courts of Kings and Temples
Authors: Green Gillian
Published: December 2007

Comparison of bas relief medallions at Angkor with medallion patterns on Chinese silk and Indian cotton textiles provides compelling evidence that fabrics from these regions were actually in use in the courts of Khmer kings. They served two purposes. One was as items of opulent palace decoration; this role transferred to stone temples, homes of the gods. Second, they represented a canopy or ceiling above a sacred space. Another group, here termed “pseudomedallions,” is described and their function speculated on. While the original textiles at Angkor have long since disappeared, their representations in stone survive as a memorial to these practices. En comparant les médaillons des bas-reliefs d'Angkor avec les motifs de médaillon sur les soieries de Chine et les cotonnades d'Inde, il ressort clairement que ces textiles ont été en usage à la cour des rois khmers. Cette utilisation fut double: pour la décoration luxueuse des palais, étendue à celle des sanctuaires de pierre, maisons des dieux; pour confectionner un dais ou couvrir un espace sacré. Un autre groupe de 'pseudo-médaillons', est également décrit et sa fonction envisagée. Alors que les textiles originaux présents à Angkor ont depuis longtemps disparu, leurs représentations lapidaires ont survécu, témoignant de leur utilisation passée.
The Significance of the Genizah's Medical Documents for the Study of Medieval Mediterranean Trade
Authors: Amar Zohar , Lev Efraim
Published: December 2007

The medical texts in the Genizah have been analyzed mainly as part of other subjects, like the various professional classes within the Jewish community in Old Cairo. Until now few have studied these documents in their own right, despite the fact that they offer valuable insights into the medieval economy of the Eastern Mediterranean and beyond. Focussing on saffron and myrobalan, this article offers a tentative investigation of the significance of medical drugs for the study of Mediterranean trade in the Middle Ages on the basis of practical medical fragments found mainly at the Taylor-Schechter collection in Cambridge. L'exploitation des textes médicaux de la Geniza a surtout servi aux sujets tels que les divers groupes professionnels de la communauté juive du vieux Caire. Jusqu'à présent de rares chercheurs ont étudiés ces manuscrits pour leur valeur intrinsèque. Pourtant, leur lecture permet d'approcher d'autres aspects de l'économie médiévale de la Méditerranée orientale et au-delà. Cette contribution, qui traite des drogues médicales, particulièrement le safran et le myrobalan, propose une première recherche sur l'importance des drogues médicales dans l'étude du commerce méditerranéen au Moyen-Âge. Elle est fondée sur les manuscrits incomplets traitant des pratiques médicales conservés principalement dans la collection Taylor-Schechter à Cambridge.
New Responses to Globalization of Scientific Research
Authors: Jiménez Jaime , Escalante Juan Carlos
Published: December 2007

The world's arrival into the era of knowledge is changing the perception of the role of science and technology in society. A good part of the scientific production appears to be linked to the needs of the global market. However, in the past few years, attempts at new forms of “doing science” have appeared throughout the globe that were very different from the current trends. Although these new forms share some characteristics that resemble those of “Mode 2,” as generally defined by Gibbons and associates in 1994, they differ drastically in the sense that they really are more socially accountable (i.e., at the grassroots level). These modes responded to a need for making scientific research more participative, more socially responsible, incorporating not only the scientists in the decision-making process but also those who have a stake in the results. In this paper, these path-breaking efforts of doing research in two Latin American countries are discussed and a comparison is made with the characteristics of Mode 2. Both cases are strongly based on the New Information and Communication Technologies (NICT). It is concluded that some segments of societies are concerned with the consequences of scientific research and are putting into practice alternative models that confront the current global trend. These models merit broader awareness and approach.
Evolutionary Psychology: 'New Science of the Mind' or 'Darwinian Fundamentalism'?
Authors: Swami Viren
Published: December 2007

As practitioners of a putative science of the mind, evolutionary psychologists have earned a degree of cachet with their provocative and sometimes controversial pronouncements about human nature and behaviour. In this article, I briefly survey the history of an evolutionary approach to the psychological sciences before considering the core assumptions of the field that has come to be known as 'evolutionary psychology'. By examining one particular example of evolutionary psychological research – on interpersonal attraction – I find this 'new science of the mind' to be lacking. Rather, I propose that developmental systems theory, buffered by a reconsideration of the dialectical sciences, offers a more comprehensive and rigorous approach to psychology. I further propose that historical materialists and those on the Left generally should take a keen interest in these issues as they have a bearing on social and political outcomes.
Towards Constructing a Chinese Information Extraction System to Support Innovations in Library Services
Authors: Zhang Zhixiong  , Li Sa  , Wu Zhengxin  , Lin Ying
Published: December 2007

Being aware of the importance of Information Extraction (IE) in supporting innovation in many areas of library services, the authors began to construct a Chinese information extraction system to effectively process huge Chinese information resources. The authors bring forth a Chinese IE solution which makes full use of the GATE (General Architecture for Text Engineering) system from the University of Sheffield, trying to develop a Chinese IE plug-in to process Chinese information resources based on the GATE framework. The article analyses the framework of the GATE system, describes the Chinese IE solution based on the GATE system and focuses on three key difficulties in the process of implementing a Chinese information extraction system. These are: 1. Chinese tokenizing problem; 2. professional gazetteers; 3. Chinese named entity recognition. The authors have successfully implemented this system and carried out an experiment in which the Chinese IE system successfully extracted thousands of pieces of science and technology news. The authors believe this system is a significant trial and lays a good foundation for future research work.
Generation XXX
Authors: Carroll Jason S. , Padilla-Walker Laura M. , Nelson Larry J. , Olson Chad D. , McNamara Barry Carolyn , Madsen Stephanie D.
Published: December 2007

This study examined correlates of pornography acceptance and use within a normative (nonclinical) population of emerging adults (individuals aged 18—26). Participants included 813 university students (500 women; M age = 20 years) recruited from six college sites across the United States. Participants completed online questionnaires regarding their acceptance and use of pornography, as well as their sexual values and activity, substance use, and family formation values. Results revealed that roughly two thirds (67% ) of young men and one half (49%) of young women agree that viewing pornography is acceptable, whereas nearly 9 out of 10 (87%) young men and nearly one third (31%) of young women reported using pornography. Results also revealed associations between pornography acceptance and use and emerging adults' risky sexual attitudes and behaviors, substance use patterns, and nonmarital cohabitation values. The discussion considers the implications of pornography use during the transition to adulthood.
Older Women and Everyday Talk about the Ageing Body
Authors: Paulson Susan , Willig Carla
Published: December 2007

This discourse analytic study shows how 10 older women, who exercise regularly or attend the University of the Third Age, adjust to the ageing body in their `everyday talk' through taking a dualist position. The part of the body which is discursively constructed as ageing becomes objectified through appealing to a wider cultural discourse of ageing as biological decline. This dualist position is embedded within a wider cultural discourse of personal agency. The individual's control of the ageing body is emphasized, the ability to monitor and manage `ageing body parts' through exerting the `active mind' and the `busy body' in activities, or simply focusing on `looking good'.
Men's Rights and Feminist Advocacy in Canadian Domestic Violence Policy Arenas
Authors: Mann Ruth M.
Published: December 2007

This article examines government and advocacy group texts on three recent Canadian domestic violence policy moments. Drawing on governance, feminist poststructuralist, and social movement perspectives, it examines men's rights advocates' and feminists' discursive actions and their influence on officials. The research aim is to explore the provisional, intrinsically incomplete, and indeed questionable success, to date, of Canadian anti-domestic violence advocates' strategies and tactics of resisting men's advocates' efforts to delegitimize gendered constructions of domestic violence. At the level of political action, the article contributes to efforts by feminists internationally to safeguard protections and supports for abused women and children in a political context marked by the increasingly prominent influence of men's rights and associated antiprogressive backlash.