bluuebunny/crossref_metadata_2025_split huggingface dataset:
Novel Characteristics of Community-Acquired Methicillin-Resistant
Staphylococcus aureus
Strains Belonging to Multilocus Sequence Type 59 in Taiwan
Authors: Takano Tomomi , Higuchi Wataru , Otsuka Taketo , Baranovich Tatiana , Enany Shymaa , Saito Kohei , Isobe Hirokazu , Dohmae Soshi , Ozaki Kyoko , Takano Misao , Iwao Yasuhisa , Shibuya Michiko , Okubo Takeshi , Yabe Shizuka , Shi Da , Reva Ivan , Teng Lee-Jene , Yamamoto Tatsuo 
Published: December 2007

ABSTRACT

Community-acquired methicillin-resistant
Staphylococcus aureus
(CA-MRSA) strains, which often produce Panton-Valentine leucocidin (PVL), are increasingly noted worldwide. In this study, we examined 42 MRSA strains (25 PVL-positive [PVL
+
] strains and 17 PVL-negative [PVL
−
] strains) isolated in Taiwan for their molecular characteristics. The PVL
+
MRSA strains included CA-MRSA strains with multilocus sequence type (ST) 59 (major PVL
+
MRSA in Taiwan), its variants, and worldwide CA-MRSA ST30 strains. The PVL
−
MRSA strains included the pandemic Hungarian MRSA ST239 strain, the Hungarian MRSA ST239 variant, MRSA ST59 (largely hospital-acquired MRSA strains) and its variants, the pandemic New York/Japan MRSA ST5 strain (Japanese type), and the MRSA ST8 strain. The major PVL
+
CA-MRSA ST59 strain possessed a tetracycline resistance-conferring (
tetK
positive) penicillinase plasmid and a drug resistance gene cluster (a possible composite transposon) for multidrug resistance. Moreover, it carried a novel staphylococcal cassette chromosome
mec
(SCC
mec
) with two distinct
ccrC
genes (
ccrC2
-
C8
). This SCC
mec
(previously named SCC
mec
type V
T
) was tentatively designated SCC
mec
type VII. Sequencing of the PVL genes revealed the polymorphisms, and the PVL
+
CA-MRSA ST59 strain possessed the ST59-specific PVL gene sequence. The data suggest that a significant amount of clonal spread is occurring in Taiwan and that the major PVL
+
CA-MRSA ST59
Taiwan
strain exhibits unique genetic characteristics, such as a novel SCC
mec
type and an ST59-specific PVL gene sequence.
Introduction
Authors: Mortimore R.N. , Duperret A. 
Published: December 2007

In 1998 a European funded research programme ROCC (Risk of Cliff Collapse) was initiated by a team from France and the UK because of the growing hazard to local commu-nities from chalk cliff retreat. Could the where, when and how of cliff collapses be answered and could the rate and scale of cliff retreat be modelled more accurately? Such answers are vital to the planners and local authorities respon-sible for the safety and access to cliffs and beaches. The primary research area is the eastern English Channel, where in northeast France there is 120km of Chalk coast, and in southeast England 40km in Sussex and a similar length in Kent. The research programme brought together geologists and engineers from BRGM, the University of Le Havre and the University of Brighton in partnership with the regional governments of the Somme, Seine Maritime, southeast England and their constituent local authorities. This book, representing several years of previous and concurrent research on the engineering geology of chalk and coastal pro-cesses, is the outcome of that research programme and allied work.
It was fortuitous that several other chalk investigations were coming to completion prior to ROCC starting. These formed a foundation on which to build the investigations. In particular, a refined Chalk lithostratigraphy with practical application to mapping and detailed correlation, was finally accepted by a joint stratigraphic committee of the Geological Society and the British Geological Survey in September 1999 (Mortimore 1986; Bristow et al. 1997; Rawson et al. 2001). This meant that
Coastal cliff geohazards in weak rock: the UK Chalk cliffs of Sussex
Authors: Mortimore R.N. , Lawrence J. , Pope D. , Duperret A. , Genter A. 
Published: December 2007

Abstract
Geohazards related to chalk coastal cliffs from Eastbourne to Brighton, Sussex are described. An eight-fold hazard classification is introduced that recognizes the influence of chalk lithology, overlying sediments and weathering processes on location, magnitude and frequency of cliff collapses. Parts of the coast are characterized by cliffs of predominantly a single chalk formation (e.g. Seven Sisters) and other sections are more complex containing several Chalk formations (Beachy Head). Rock properties (intact dry density or porosity) and mass structure vary with each formation and control cliff failure mechanisms and scales of failures. The Holywell Nodular Chalk, New Pit Chalk and Newhaven Chalk formations are characterized by steeply inclined conjugate sets of joints which lead to predominantly plane and wedge failures. However, the dihedral angle of the shears, the fracture roughness and fill is different in each of these formations leading to different rock mass shear strengths. In contrast the Seaford and Culver Chalk formations are characterized by low-density chalks with predominantly clean, vertical joint sets, more closely spaced than in the other formations. Cliff failure types range from simple joint controlled conventional plane and wedge failures to complex cliff collapses and major rock falls (partial flow-slides) involving material failure as well as interaction with discontinuities. Other hazards, related to sediments capping the Chalk cliffs, include mud-slides and sandstone collapses at Newhaven, and progressive failure of Quaternary Head and other valley-fill deposits. Weathering, including the concentration of groundwater flow down dissolution pipes and primary discontinuities, is a major factor on rate and location of cliff collapses. A particular feature of the Chalk cliffs is the influence of folding on cliff stability, especially at Beachy Head, Seaford Head and Newhaven. A new classification for cliff collapses and a new scale of magnitude for collapses are introduced and used to identify, semi-quantify and map the different hazards.
Climate (and climate change) and marine erosion affect the rate of development of cliff collapse and cliff-line retreat. This was particularly evident during the wet winters of 1999–2000–2001 when the first major collapses along protected sections of coastline occurred (Peacehaven Cliffs protected by an undercliff wall; Black Rock Marina the Chalk cliffs and the Quaternary Head). It is the geology, however, that controls the location and scale of erosion and cliff failure.
Laboratory abrasion tests on beach flint shingle
Authors: Dornbusch U. , Moses C. A. , Robinson D. A. , Williams R. B. G. 
Published: December 2007

Abstract

Laboratory tumbling experiments demonstrate that rounded flint beach shingle is less durable than commonly supposed. The mean rate of abrasion for dark grey Sussex flints (Senonian) in the first few hours of tumbling increases with weight whereas that of white Normandy flints (Turonian and Coniacian) does not. Depending on pebble weight, the Sussex flints abrade at up to six times the rate of the Normandy flints. Abrasion rates also vary according to tumbler load, the water:shingle ratio, and tumbling period. The abrasion rate of Sussex flints decreases with time at a much greater rate than could be expected from the reduction in size. The abrasion debris is mostly silt sized, but small quantities of sand are produced from samples containing larger pebbles.
In situ
abrasion of flint shingle is estimated to be significant, reducing the protection shingle beaches afford to cliffs thus exacerbating Chalk cliff instability.
Early kinematic history of the Goban Spur rifted margin derived from a new model of continental breakup and sea-floor spreading initiation
Authors: Healy D. , Kusznir N. J. 
Published: December 2007

Abstract
Deformation of continental lithosphere leading to breakup and the initiation of sea-floor spreading can be described in terms of an upwelling divergent flow field within the continental lithosphere and asthenosphere. A new model (SfMargin) of rifted continental margin formation using this upwelling divergent flow field has been developed that successfully predicts lithosphere depth-dependent stretching and mantle exhumation at rifted margins. The kinematics of this flow field has important consequences for the bathymetric (subsidence) and thermal history of continental margin lithosphere. We apply the new model to a profile through the Goban Spur on the eastern Atlantic continental margin. Forward modelling yields parameter values describing the kinematics of the flow field leading to continental breakup and sea-floor spreading initiation that are consistent with the known amagmatic history of this margin. We employ a grid search method to systematically explore model parameter space and provide an assessment of the sensitivity of the model to the kinematic flow field parameter values. The preferred forward model parameters coincide with low values of misfit with respect to observed present-day bathymetry and free air gravity anomalies. Our results reveal the early kinematic history of the Goban Spur margin as characterized by a ratio of upwelling rate to half-spreading rate of unity, consistent with that expected for the initiation of sea-floor spreading at a non-volcanic rifted margin and only a modest amount of prebreakup lithospheric stretching (β=1.5). These results conform with recent observations of depth-dependent stretching and serpentinized mantle exhumation at this amagmatic rifted continental margin.
The boundary between continental rifting and sea-floor spreading in the Woodlark Basin, Papua New Guinea
Authors: Goodliffe A. M. , Taylor B. 
Published: December 2007

Abstract
Seismic reflection, bathymetry, acoustic imagery and magnetic data are presented that encompass the boundary between rifting of the Papuan continent and westward propagating sea-floor spreading in the Woodlark Basin. West of the spreading tip, the southern margin is characterized by large fault blocks, which were tilted to the south on north-dipping normal faults during the current rifting phase, and graben further south where previous rifting failed. The northern margin is devoid of large offset normal faults and its subsidence from near sea level requires synrift flow of the lower crust. The margin asymmetry primarily reflects across-strike differences in the prerift geology, morphology and rheology. Horst and graben with 3 km relief below sea level occur adjacent to the spreading tip. Although heat flow data imply greater crustal thinning to the south of Moresby continental seamount, seismicity shows that deformation is currently focused on the Moresby normal fault that bounds its northern side. Based on logging results from ODP Leg 180 and semblance analysis, depth conversion of seismic reflection data show that Moresby Fault has a dip ≥29°, which is compatible with an earthquake slip plane of 30°–33°. Directly east of Moresby Seamount, the first spreading segment is identified on the basis of magnetic, bathymetry and sidescan data to comprise two ring dykes in the west and Cheshire Seamount in the east. A seismic reflection line crossing the western ring dyke shows an intrusive body that cuts Moresby Fault at depth. Currently, intrusive rocks have only reached the surface near the ring dyke, leaving flat-lying synrift sediments, sills (?) and surface lava flows overlying the main intrusive body. The boundary between continental rifting and sea-floor spreading in the Woodlark Basin is spatially abrupt, although the processes overlap in time. The progression from rifting to spreading is characterized by a decrease in sedimentation as the margins are progressively thinned, subside below sea level, are eroded less and trap sediments in proximal basins. The post-rift sedimentation near the continent–ocean boundary is hemipelagic and drapes breakup topography without a distinct breakup unconformity. Synrift sediments, deposited above the 8.4 Ma rift onset unconformity and prior to breakup, are characterized by rotated sections (with parallel or diverging reflectors) as well as by ponded sections that onlap bounding fault blocks where local extension has ceased. Splayed reflectors representing sediment deposition on rotating fault blocks do not characterize the full synrift section, but only those times and places where extension is localized.
The role of gravitational instabilities, density structure and extension rate in the evolution of continental margins
Authors: Burov E. 
Published: December 2007

Abstract

Formation of rifted continental margins is associated with localized thinning and breakup of the continental lithosphere, driven or accompanied by the ascent of the lithosphere–asthenosphere boundary. Thinning creates sharp density and viscosity contrasts and steep boundaries between cold deformed lithosphere and hot upwelling asthenosphere, thus providing conditions for the development of positive (asthenosphere) and negative (mantle lithosphere) Rayleigh–Taylor (RT) instabilities. The evolution of many continental margins (e.g. Newfoundland margin and Iberian margin) is characterized by slow spreading rates. This allows the RT instabilities to grow at the timescale of rifting. The impact of positive RT instabilities (asthenospheric upwelling) is well studied. The negative RT instabilities, associated with mantle down-welling, remain an overlooked factor. However, these instabilities should also affect the rift evolution, in particular, they may cause mantle thinning or thickening below the rift flanks. Our numerical experiments suggest that the ratio of the RT-growth rate to the extension rate controls the overall rift geometry and evolution. Even if the effect of negative RT instabilities is more important for slow extension rates of 2×5 mm year
−1
(Deborah number,
De
<1), it is still significant for 2–3 times higher extension rates of 2×15 mm year
−1
(
De
<10). The numerical experiments for extension rates of 2×15 mm year
−1
and mantle–asthenosphere density contrasts of 10–20 kg m
−3
demonstrate a number of structural similarities with continental margins characterized by low
De
(e.g. Flemish Cap and Galicia margin). In particular, rift asymmetry results from interplay between the RT instabilities and differential stretching at
De
<1. Formation of interior basins occurs at
De
≈1–3. The best correspondence with the observed geometry of rifted margins is obtained for chemical density contrast of 20 kg m
−3
and extension rate of 2×15 mm year
−1
, which is twice that of the averaged values inferred from the observations. This suggests that margins may initially (prebreakup stage) extend at higher rates than the average extension rates characterizing rift evolution. The influence of RT instabilities is strongly controlled by extension rate, density, rheology and thermal structure of the lithosphere; this implies that we need better constraints on these parameters from the observations.
A dynamic model of rifting between Galicia Bank and Flemish Cap during the opening of the North Atlantic Ocean
Authors: Harry D. L. , Grandell S. 
Published: December 2007

Abstract
A finite-element model is used to simulate Late Jurassic–Early Cretaceous rifting between the Flemish Cap and Galicia Bank continental margins. The model results show that variations in the thickness of the continental crust on these margins at wavelengths greater than about 75 km can be explained as a consequence of the interaction of two pre-existing weaknesses in the lithosphere. A weakness in the crust, attributed to structural fabrics in the Variscan front, controls the location of crustal extension during the early stages of rifting in the model. This results in formation of a broad rift basin similar to the Galicia Interior Basin. A deep-seated weakness located 110 km further west, attributed to the thick crust beneath the central Variscan Orogen, controls the location of mantle necking. Extension in this region is initially diffuse, but accelerates and becomes more focused with time. Approximately 13 million years after rifting begins, the locus of crustal extension shifts from the region of pre-weakened crust into the region of pre-weakened mantle. This marks the end of subsidence in the Galicia Interior Basin and the onset of subsidence in the Flemish Cap and Galicia Bank marginal basins. Extension in these areas continues for another 12 million years before continental breakup. The asthenosphere does not ascend to depths shallow enough for decompression melting to begin until less than 5 million years before the onset of sea-floor spreading. The model predicts that all late-stage synrift magmatism during this period is limited to within 45 km of the rift axis, and production of melt thicknesses greater than 2 km is restricted to within 35 km of the rift axis. Mantle potential temperatures of 1250–1275 °C, ∼5–30 °C cooler than normal, result in 3.1–4.5 km-thick oceanic crust at the time of breakup, in general agreement with the 2–4 km thick crust observed adjacent to these margins.
A kinematic modelling approach to lithosphere deformation and basin formation: application to the Black Sea
Authors: Egan S. S. , Meredith D. J. 
Published: December 2007

Abstract
A kinematic model of lithosphere deformation has been developed that integrates the following components: structural deformation of the crust and mantle lithosphere; thermal conditioning, perturbation and subsequent re-equilibration of the lithosphere temperature field; flexural isostatic adjustments; and surface processes, including both lateral and temporal variations in basin fill and bathymetry. This approach enables the forward modelling of extensional basin evolution in two and three dimensions followed by deformation due to subsequent extensional and compressional (i.e. inversion) events.
The model has been applied to the Black Sea, which is one of the deepest basins in the world and yet it is poorly understood in terms of the mechanisms that have controlled its evolution. Although it is widely accepted that this basin was initiated by Mesozoic back-arc extension related to the subduction of the Tethys Plate to the south, most of the subsidence observed today occurred within the Palaeogene and Neogene (i.e. within the framework of the Alpine–Himalayan orogenic belt). The modelling approach described above has been used to test possible geological and geodynamic mechanisms that have controlled the subsidence history of the Black Sea. In particular, the investigation has focused on trying to explain the anomalously thick post-rift subsidence that occurred in the basin. Models assuming uniform lithosphere extension do not generate the observed thickness of sediment infill in the basin. Similarly, modelling of the compressional deformation around the edges of the basin structure does little to explain the large magnitude of subsidence within the centre of the basin. Model results show that the observed basin depths can be attained only when the total magnitude of deformation is constrained from crustal thickness changes rather than by fault displacement measurements.
Joint Effects of Dietary Trace Metals and DNA Repair Capacity in Lung Cancer Risk
Authors: Mahabir Somdat , Forman Michele R. , Barerra Stephanie L. , Dong Yong Q. , Spitz Margaret R. , Wei Qingyi 
Published: December 2007

AbstractIn a large case-control study, we previously reported that dietary intakes of zinc (Zn) and copper (Cu), but not selenium (Se), were inversely associated with lung cancer risk. Because Zn, Cu, Se, iron (Fe), and calcium (Ca) are important for maintaining DNA stability, we examined their associations with DNA repair capacity (DRC) measured by the lymphocyte host-cell reactivation assay in 1,139 cases and 1,210 of the controls. Dietary intake was reported in a food frequency questionnaire. In multivariate analyses, compared to those with high dietary Cu + proficient DRC, the odds ratio (95% confidence interval) [OR (95% CI)] for lung cancer for low Cu + suboptimal DRC was 2.54 (1.97-3.27). Similar results were observed for men and women. These effects were more pronounced in older and lean subjects, those with late-stage disease, and those with a family history of cancer in first-degree relatives. Compared to subjects with high Zn + proficient DRC, the OR for lung cancer for low Zn + suboptimal DRC was 1.82 (95% CI, 1.41-2.34), with pronounced effects in men, current smokers, subjects with longer duration of smoking, those with late-stage disease, or those with a family history of cancer. An OR of 1.94 (95% CI, 1.51-2.48) was observed for low Fe + suboptimal DRC compared with high Fe + proficient DRC, and pronounced effects appeared in older, lean subjects, those with longer duration of smoking, are heavier smokers, those with a late-stage disease, and those with a family history of cancer. No significant joint associations were seen for Se or Ca and DRC. Our joint associations between Cu-DRC, Zn-DRC and Fe-DRC and lung cancer risk require confirmation in prospective studies. (Cancer Epidemiol Biomarkers Prev 2007;16(12):2756–62)
Dairy Products, Calcium Intake, and Risk of Prostate Cancer in the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial
Authors: Ahn Jiyoung , Albanes Demetrius , Peters Ulrike , Schatzkin Arthur , Lim Unhee , Freedman Michal , Chatterjee Nilanjan , Andriole Gerald L. , Leitzmann Michael F. , Hayes Richard B. ,   for the Prostate, Lung, Colorectal, and Ovarian Trial Project Team
Published: December 2007

AbstractHigher intakes of calcium and dairy products, a major source of dietary calcium, are reported to increase the risk of prostate cancer, potentially due to reductions in circulating vitamin D with increasing calcium intake. We prospectively examined the association of dairy product and calcium intake with prostate cancer risk in 29,509 men, including 1,910 cases, in the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial. We also evaluated the relation of calcium intake with serum 25-hydroxy-vitamin D [25(OH)D] and 1,25-dihydroxy-vitamin D [1,25(OH)2D], in a Prostate, Lung, Colorectal, and Ovarian Trial substudy (n = 275). Dietary intake was assessed using a food frequency questionnaire. Baseline serum 1,25(OH)2D was determined by RIA. Greater intake of dairy products, particularly low-fat dairy products, was weakly associated with increased risk of prostate cancer [relative risk (RR), 1.12; 95% confidence intervals (CI), 0.97-1.30; P trend = 0.06 for &gt;2.75 versus ≤0.98 servings of total dairy/day; 1.23 (1.07-1.41) for low-fat dairy]. Greater dietary calcium intake was associated with increased risk of prostate cancer (RR, 1.34; 95% CI, 0.93-1.94; P trend = 0.02 for &gt;2,000 versus &lt;1,000 mg/day), but greater supplementary calcium intake was not associated with the risk. Associations of dairy product and dietary calcium intake were evident for nonaggressive disease (RR, 1.20; 95% CI, 0.99-1.46; P trend = 0.01 for dairy products; 1.64, 1.04-2.57; P trend = 0.002 for dietary calcium), but not aggressive disease (RR, 1.02; 95% CI, 0.81-1.28 for dairy products; 0.94, 0.49-1.80 for dietary calcium). Calcium intake was not associated with serum 25-hydroxy-vitamin D and 1,25(OH)2D concentration. In this large prospective study in a prostate cancer screening trial, greater dietary intake of calcium and dairy products, particularly low-fat types, may be modestly associated with increased risks for nonaggressive prostate cancer, but was unrelated to aggressive disease. Furthermore, we found no relationship between calcium intake and circulating vitamin D. (Cancer Epidemiol Biomarkers Prev 2007;16(12):2623–30)