bluuebunny/crossref_metadata_2025_split huggingface dataset:
Physical characteristics of tephra layers in the deep sea realm: the Campanian Ignimbrite eruption
Authors: Engwell S. L. , Sparks R. S. J. , Carey S. 
Published: February 2014

Abstract

Tephra deposits in the deep sea can survive undisturbed for long periods of time and, on regional scales, tend to be much better preserved than their subaerial counterparts. In this study, grain size distributions and thicknesses of tephra deposits from the Campanian Ignimbrite (CI) eruption (39 000 yr BP; magnitude
c.
7.7) preserved in thirty-three deep sea cores are analysed to infer key eruption parameters. Distal deep sea tephra thickness data show an exponential decrease with distance from source. Such trends are difficult to identify in distal subaerial data owing to reworking and limited exposure. We find that tephra grain size distributions are much less affected by depositional environment than thickness, with trends that are consistent across distal subaerial, lacustrine and deep sea environments. The CI layer exhibits bimodal grain size distributions to distances of
c.
1000 km, after which it becomes unimodal. Such trends can be related to different mechanisms of tephra transport in the atmosphere, whereby at proximal to medial distances the Plinian and co-ignimbrite phases produce distinct plumes. Within 150 and 900 km from source, Plinian tephra constitutes 40±5% of the deposit volume. Beyond this region where coarse particles are deposited, the plumes merge and fines derived largely from co-ignimbrite elutriation are spread in the atmosphere at velocities greater than the settling velocities of the particles.
New insights into the Andean crustal structure between 32° and 34°S from GOCE satellite gravity data and EGM2008 model
Authors: Alvarez O. , Gimenez M. E. , Martinez M. P. , Lince Klinger F. , Braitenberg C. 
Published: February 2014

Abstract
The subduction of the Nazca oceanic plate under the South American plate in the south-central Andes region is characterized by the oblique collision of the Juan Fernandez Ridge against the continental margin. The upper plate is characterized by a broken foreland, a thrust-and-fold belt and eastward migration of the volcanic arc promoted by the flattening of the slab. Topographic load, thermal state and plate rheology determine the isostatic state of the continental plate. We calculated the vertical gravity gradient from GOCE satellite data in order to delineate the main tectonic features related to density variations resulting from internal and external loads. Then, using the Bouguer anomaly, we calculated the crust–mantle discontinuity and the elastic thickness in the frame of the isostatic lithospheric flexure model applying the convolution method approach. The results obtained show substantial variations in the structure of the continental lithosphere related to variations in the subduction angle of the Nazca plate. These variations are reflected in the varying Moho depths and in the plate rigidity, presenting a distinct behaviour in the southern zone, where the oceanic plate subducts with an approximate ‘normal’ angle with respect to the northern zone of the study area where the flat slab occurs.
Quaternary shortening at the orogenic front of the Central Andes of Argentina: the Las Peñas Thrust System
Authors: Costa Carlos H. , Ahumada Emilio A. , Gardini Carlos E. , Vázquez Fabricio R. , Diederix Hans 
Published: February 2014

Abstract

The NNW-trending Las Peñas Thrust System is one of the key structures along the Andean orogenic front between 32°15′ and 32°40′S in the Southern Precordillera of Argentina. This east-verging structure crops out over a distance of
c.
40 km and provides one of the best opportunities for a detailed field survey of Quaternary thrusting in the Andean frontal deformation zone. We present a systematic description of the geometry and geomorphic signatures of the main thrust deformation zone, which emplaces Neogene rocks over Quaternary alluvium, and usually behaves as a blind propagating thrust into the youngest (Late Pleistocene–Holocene) alluvial deposits. The Las Peñas Thrust System is understood to represent the latest stage of the eastward migration of an imbricated fan structure, which has driven the neotectonic uplift of the Las Peñas–Las Higueras range. Excellent outcrops provided by well-incised creek outlets reveal that the thrust system is made up either by a single fault surface or by two or more frontal splays. Several sections along its length can be differentiated on the basis of thrust geometries and/or morphotectonic features. The northern sections are characterized by isolated outcrops of Neogene rocks in the hanging wall, surrounded by alluvial bajadas. Remnants of fold limbs scarps depict the geomorphic signature of the thrust propagation into the Quaternary layers, although the preserved topographic relief always underestimates the cumulated thrust slip during the Quaternary. The southern part of this thrust system is defined by a frontal range, cored by a transposed south-plunging anticline in bedrock. Our observations suggest a dynamic and unsteady interaction between thrust propagation and sedimentation/erosion processes along the thrust trace during deposition of the Quaternary alluvial layers.
Characterizing the Paleocene turbidites of the North Sea: Maureen Formation, UK Central Graben
Authors: Kilhams Ben , Hartley Adrian , Huuse Mads , Davis Chris 
Published: February 2014

Abstract
This study presents an integrated seismic, well and core-based analysis of the Maureen Formation in the Central Graben of the North Sea. Facies analysis reveals that it is possible to divide the Maureen sandstones into amalgamated, sand- and mud-prone divisions, but that the related chalk facies are complex and imply a range of depositional processes including pelagic fallout, debris flows and turbidity currents. These chalk deposits have an impact on the interpretation of amplitude-based seismic attribute volumes. Detailed petrophysical mapping, supported by seismic analysis, reveals that the Maureen sandstones were deposited in distinct western and eastern fairways controlled by the relict Mesozoic rift topography (although offset stacking is an important intragraben process). The spatial extent of the Maureen sandstones is similar to the overlying Sele and Lista formations and suggests that the broad controls on sediment routing were the same throughout the Lower Palaeogene. Other similarities between these systems include the role of sandstone texture in controlling reservoir quality (although the heterolithic nature of the Maureen sandstones means that porosities and permeabilities are lower). A pattern of intraformational progradation and late-stage backstepping of the sandstone units is likely related to sea-level variability.
Depositional controls on fluid flow in the Gannet A Field
Authors: Lynn Gwilym J. , Bacciotti Morgan , Van Bergen Pim F. , Gray Kirsten R. 
Published: February 2014

Abstract
The Gannet A Field is an Eocene-aged Tay Sandstone Member reservoir located in the Central North Sea, with a thin oil rim and overlying gas cap that was developed in the early 1990s. The field comprises a very high quality reservoir and is connected to a large and active aquifer. These two factors in combination have led to a highly dynamic system during production, with significant migration of fluids around the field as offtake evolved. A considerable amount of surveillance data, including time-lapse (4D) seismic data, oil geochemical sampling and cased-hole saturation logs, has been acquired that allows the fluid flow and contact movement within the reservoir to be tracked. Integration of the individual datasets has allowed the key controls on fluid flow in the reservoir to be determined. The depositional architecture has strongly influenced reservoir behaviour, with the positioning and geometry of the non-net facies being the primary control on fluid flow, water-cut development and fluid distributions throughout the field. This has been demonstrated through static and dynamic reservoir modelling and validation of the results with the surveillance data.
Detection of Cancer DNA in Plasma of Patients with Early-Stage Breast Cancer
Authors: Beaver Julia A. , Jelovac Danijela , Balukrishna Sasidharan , Cochran Rory L. , Croessmann Sarah , Zabransky Daniel J. , Wong Hong Yuen , Valda Toro Patricia , Cidado Justin , Blair Brian G. , Chu David , Burns Timothy , Higgins Michaela J. , Stearns Vered , Jacobs Lisa , Habibi Mehran , Lange Julie , Hurley Paula J. , Lauring Josh , VanDenBerg Dustin A. , Kessler Jill , Jeter Stacie , Samuels Michael L. , Maar Dianna , Cope Leslie , Cimino-Mathews Ashley , Argani Pedram , Wolff Antonio C. , Park Ben Ho 
Published: February 2014

Abstract
Purpose: Detecting circulating plasma tumor DNA (ptDNA) in patients with early-stage cancer has the potential to change how oncologists recommend systemic therapies for solid tumors after surgery. Droplet digital polymerase chain reaction (ddPCR) is a novel sensitive and specific platform for mutation detection.
Experimental Design: In this prospective study, primary breast tumors and matched pre- and postsurgery blood samples were collected from patients with early-stage breast cancer (n = 29). Tumors (n = 30) were analyzed by Sanger sequencing for common PIK3CA mutations, and DNA from these tumors and matched plasma were then analyzed for PIK3CA mutations using ddPCR.
Results: Sequencing of tumors identified seven PIK3CA exon 20 mutations (H1047R) and three exon 9 mutations (E545K). Analysis of tumors by ddPCR confirmed these mutations and identified five additional mutations. Presurgery plasma samples (n = 29) were then analyzed for PIK3CA mutations using ddPCR. Of the 15 PIK3CA mutations detected in tumors by ddPCR, 14 of the corresponding mutations were detected in presurgical ptDNA, whereas no mutations were found in plasma from patients with PIK3CA wild-type tumors (sensitivity 93.3%, specificity 100%). Ten patients with mutation-positive ptDNA presurgery had ddPCR analysis of postsurgery plasma, with five patients having detectable ptDNA postsurgery.
Conclusions: This prospective study demonstrates accurate mutation detection in tumor tissues using ddPCR, and that ptDNA can be detected in blood before and after surgery in patients with early-stage breast cancer. Future studies can now address whether ptDNA detected after surgery identifies patients at risk for recurrence, which could guide chemotherapy decisions for individual patients. Clin Cancer Res; 20(10); 2643–50. ©2014 AACR.
Bone Marrow–Derived Mesenchymal Stromal Cells Promote Survival and Drug Resistance in Tumor Cells
Authors: Bergfeld Scott A. , Blavier Laurence , DeClerck Yves A. 
Published: February 2014

AbstractBone marrow mesenchymal stromal cells (BMMSC) have antitumorigenic activities. Here, we hypothesized that circulating BMMSC are incorporated into tumors and protect tumor cells from therapy-induced apoptosis. Adherent cells harvested from murine bone marrow and expressing phenotypic and functional characteristics of BMMSC were tested for their antitumor activity against murine 4T1 mammary adenocarcinoma and LL/2 Lewis lung carcinoma cells. BMMSC but not NIH3T3 or murine skin fibroblasts stimulated the expansion of 4T1 cells in three-dimensional (3D) cocultures, and conditioned medium (CM) from these cells increased the viability of 4T1 and LL/2 cells in two-dimensional (2D) cultures. 4T1 cells exposed to BMMSC CM exhibited a 2-fold reduction in apoptosis under low serum concentrations (0.5% to 1%). Furthermore, exposure of 4T1 and LL/2 cells to BMMSC CM increased their viability in the presence of paclitaxel or doxorubicin at therapeutic concentrations. This effect was accompanied by reductions in caspase-3 activity and Annexin V expression. When coinjected with 4T1 cells in the mammary fat pad of mice subsequently treated with doxorubicin, BMMSC (and not fibroblasts) also inhibited drug-induced apoptosis in tumor cells by 44%. We demonstrated that BMMSC were attracted by 4T1 and LL/2 cells but not by NIH3T3 cells in vitro and that when injected intravenously in 4T1 tumor-bearing mice, these cells (and not NIH3T3) were specifically detected in tumors within 12 to 18 days in which they preferentially localized at the invasive front. Overall, our data identify BMMSC as an important mediator of tumor cell survival and treatment resistance in primary tumors. Mol Cancer Ther; 13(4); 962–75. ©2014 AACR.
Novel Roles for ERK5 and Cofilin as Critical Mediators Linking ERα-Driven Transcription, Actin Reorganization, and Invasiveness in Breast Cancer
Authors: Madak-Erdogan Zeynep , Ventrella Rosa , Petry Luke , Katzenellenbogen Benita S. 
Published: February 2014

Abstract
Cancer cell motility and invasiveness are fundamental characteristics of the malignant phenotype and are regulated through diverse signaling networks involving kinases and transcription factors. This study establishes an estrogen receptor (ERα)/MAPK (ERK5)/cofilin (CFL1) network that specifies the degree of breast cancer cell aggressiveness through coupling of actin reorganization and hormone receptor–mediated transcription. Using dominant negative and constitutively active forms, as well as small-molecule inhibitors of extracellular signal–regulated kinase (ERK)5 and MAP–ERK kinase (MEK)5, it was revealed that hormone activation of ERα determined the subcellular localization of ERK5, which functions as a coregulator of ERα-dependent gene transcription. Notably, ERK5 acted in concert with the actin remodeling protein, CFL1, and upon hormone exposure, both localized to active nuclear transcriptional hubs as verified by immunofluorescence and proximity ligation assays. Both ERK5 and CFL1 facilitated PAF1 recruitment to the RNA Pol II complex and both were required for regulation of gene transcription. In contrast, in cells lacking ERα, ERK5 and CFL1 localized to cytoplasmic membrane regions of high actin remodeling, promoting cell motility and invasion, thereby revealing a mechanism likely contributing to the generally poorer prognosis of patients with ERα-negative breast cancer. Thus, this study uncovers the dynamic interplay of nuclear receptor–mediated transcription and actin reorganization in phenotypes of breast cancer aggressiveness.
Implications: Identification of the ER/ERK5/CFL1 axis suggests new prognostic biomarkers and novel therapeutic avenues to moderate cancer aggressiveness. Mol Cancer Res; 12(5); 714–27. ©2014 AACR.
Guidelines for the Prevention of Stroke in Women
Authors: Bushnell Cheryl , McCullough Louise D. , Awad Issam A. , Chireau Monique V. , Fedder Wende N. , Furie Karen L. , Howard Virginia J. , Lichtman Judith H. , Lisabeth Lynda D. , Piña Ileana L. , Reeves Mathew J. , Rexrode Kathryn M. , Saposnik Gustavo , Singh Vineeta , Towfighi Amytis , Vaccarino Viola , Walters Matthew R. 
Published: February 2014

Purpose—
The aim of this statement is to summarize data on stroke risk factors that are unique to and more common in women than men and to expand on the data provided in prior stroke guidelines and cardiovascular prevention guidelines for women. This guideline focuses on the risk factors unique to women, such as reproductive factors, and those that are more common in women, including migraine with aura, obesity, metabolic syndrome, and atrial fibrillation.

Methods—
Writing group members were nominated by the committee chair on the basis of their previous work in relevant topic areas and were approved by the American Heart Association (AHA) Stroke Council’s Scientific Statement Oversight Committee and the AHA’s Manuscript Oversight Committee. The panel reviewed relevant articles on adults using computerized searches of the medical literature through May 15, 2013. The evidence is organized within the context of the AHA framework and is classified according to the joint AHA/American College of Cardiology and supplementary AHA Stroke Council methods of classifying the level of certainty and the class and level of evidence. The document underwent extensive AHA internal peer review, Stroke Council Leadership review, and Scientific Statements Oversight Committee review before consideration and approval by the AHA Science Advisory and Coordinating Committee.

Results—
We provide current evidence, research gaps, and recommendations on risk of stroke related to preeclampsia, oral contraceptives, menopause, and hormone replacement, as well as those risk factors more common in women, such as obesity/metabolic syndrome, atrial fibrillation, and migraine with aura.

Conclusions—
To more accurately reflect the risk of stroke in women across the lifespan, as well as the clear gaps in current risk scores, we believe a female-specific stroke risk score is warranted.
Mice With Targeted Inactivation of
Ppap2b
in Endothelial and Hematopoietic Cells Display Enhanced Vascular Inflammation and Permeability
Authors: Panchatcharam Manikandan , Salous Abdel K. , Brandon Jason , Miriyala Sumitra , Wheeler Jessica , Patil Pooja , Sunkara Manjula , Morris Andrew J. , Escalante-Alcalde Diana , Smyth Susan S. 
Published: February 2014

Objective—

Lipid phosphate phosphatase 3 (LPP3), encoded by the
PPAP2B
gene, is an integral membrane enzyme that dephosphorylates, and thereby terminates, the G-protein–coupled receptor–mediated signaling actions of lysophosphatidic acid (LPA) and sphingosine-1-phosphate. LPP3 is essential for normal vascular development in mice, and a common
PPAP2B
polymorphism is associated with increased risk of coronary artery disease in humans. Herein, we investigate the function of endothelial LPP3 to understand its role in the development and human disease.

Approach and Results—

We developed mouse models with selective LPP3 deficiency in endothelial and hematopoietic cells. Tyrosine kinase
Tek
promoter–mediated inactivation of
Ppap2b
resulted in embryonic lethality because of vascular defects. LPP3 deficiency in adult mice, achieved using a tamoxifen-inducible Cre transgene under the control of the Tyrosine kinase
Tek
promoter, enhanced local and systemic inflammatory responses. Endothelial, but not hematopoietic, cell LPP3 deficiency led to significant increases in vascular permeability at baseline and enhanced sensitivity to inflammation-induced vascular leak. Endothelial barrier function was restored by pharmacological or genetic inhibition of either LPA production by the circulating lysophospholipase D autotaxin or of G-protein–coupled receptor–dependent LPA signaling.

Conclusions—
Our results identify a role for the autotaxin/LPA-signaling nexus as a mediator of endothelial permeability in inflammation and demonstrate that LPP3 limits these effects. These findings have implications for therapeutic targets to maintain vascular barrier function in inflammatory states.
Systolic and Diastolic Mechanics in Stress Cardiomyopathy
Authors: Medeiros Keith , O’Connor Mark J. , Baicu Catalin F. , Fitzgibbons Timothy P. , Shaw Peter , Tighe Dennis A. , Zile Michael R. , Aurigemma Gerard P. 
Published: February 2014

Background—
Stress cardiomyopathy (SCM) is a peculiar form of reversible left ventricular dysfunction seen predominantly in women and occurs in response to emotional or physical stress. Because dysfunction in SCM is reversible and that of acute myocardial infarction (MI) is not, we hypothesized that these fundamental mechanistic differences between SCM and MI would be associated with different systolic and diastolic properties.

Methods and Results—

We examined 3 groups, all women: patients with SCM (n=24; mean age, 63±12 years), those with left anterior (LAD) ST-segment–elevation MI (n=36; mean age, 63±10 years), and referent control subjects (n=30; mean age, 62±8 years). All underwent angiography, ventriculography, and pressure measurements within 48 hours of presentation. Left ventricular volumes, diastolic pressures, and diastolic stiffness were higher in SCM and LAD MI patients than in control subjects but no different from each other. Similarly, left ventricular diastolic pressures and diastolic stiffness were elevated in the SCM and LAD MI groups compared with the control group. Left ventricular ejection fraction in SCM and LAD MI were 40.8±12.3% and 49.6±5.6%, respectively, versus 70.4±9.4% in control subjects (
P
<0.001), and stroke work less than half the value of control subjects. Indexes of contractility and ventricular-arterial coupling were similarly abnormal in SCM and LAD MI.

Conclusions—
SCM and LAD MI show severe diastolic dysfunction. At similar left ventricular volumes, their diastolic pressures are more than twice as high as in control subjects, and systolic dysfunction is equally reduced in SCM and LAD MI. Despite a completely different pathophysiology in terms of systolic and diastolic function, SCM is indistinguishable from acute LAD-territory MI.
Impact of Pretreatment Noncontrast CT Alberta Stroke Program Early CT Score on Clinical Outcome After Intra-Arterial Stroke Therapy
Authors: Yoo Albert J. , Zaidat Osama O. , Chaudhry Zeshan A. , Berkhemer Olvert A. , González R. Gilberto , Goyal Mayank , Demchuk Andrew M. , Menon Bijoy K. , Mualem Elan , Ueda Dawn , Buell Hope , Sit Siu Po , Bose Arani 
Published: February 2014

Background and Purpose—
The efficacy of intra-arterial treatment remains uncertain. Because most centers performing IAT use noncontrast CT (NCCT) imaging, it is critical to understand the impact of NCCT findings on treatment outcomes. This study aimed to compare functional independence and safety among patients undergoing intra-arterial treatment stratified by the extent of ischemic change on pretreatment NCCT.

Methods—
The study cohort was derived from multicenter trials of the Penumbra System. Inclusion criteria were anterior circulation proximal occlusion, evaluable pretreatment NCCT, and known time to reperfusion. Ischemic change was quantified using the Alberta Stroke Program Early CT Score (ASPECTS) and stratified into 3 prespecified groups for comparison: 0 to 4 (most ischemic change) versus 5 to 7 versus 8 to 10 (least ischemic change).

Results—

A total of 249 patients were analyzed: 40 with ASPECTS 0 to 4, 83 with ASPECTS 5 to 7, and 126 with ASPECTS 8 to 10. For ASPECTS 0 to 4, 5 to 7, and 8 to 10, respectively, good outcome (modified Rankin Scale score, 0–2) rates were 5%, 38.6%, and 46% (
P
<0.0001), and mortality rates were 55%, 28.9%, and 19% (
P
=0.0001). The only significant pairwise differences were between ASPECTS 0 to 4 and other groups. Symptomatic hemorrhage was more common with lower ASPECTS (
P
=0.02). Shorter time to reperfusion was significantly associated with better outcomes among patients with ASPECTS 8 to 10 (
P
=0.01). A similar relationship was seen for ASPECTS 5 to 7 but was not statistically significant. No such relationship was seen for ASPECTS 0 to 4.

Conclusions—
NCCT seems useful for excluding patients with the greatest burden of ischemic damage from futile intra-arterial treatment, which is unlikely to result in patient functional independence and increases the risk of hemorrhage.