Publications by authors named "Stegman D"

During the Cretaceous, the Indian plate moved towards Eurasia at the fastest rates ever recorded. The details of this journey are preserved in the Indian Ocean seafloor, which document two distinct pulses of fast motion, separated by a noticeable slowdown. The nature of this rapid acceleration, followed by a rapid slowdown and then succeeded by a second speedup, is puzzling to explain.

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Background/aims: The goal of this study was to determine the effect of dietary genistein (naturally occurring phytoestrogen) on jejunal secretory function in a clinically relevant model of diabetes and obesity, the leptin-defIcient ob/ob mouse.

Methods: We measured transepithelial short circuit current (Isc), across freshly isolated segments of jejunum from 12-week old male and female ob/ob and lean C57Bl/6J mice fed a genistein diet (600 mg genistein/kg diet) for 4-weeks. Separate segments of jejunum were frozen for western blot determination of key proteins involved in secretory transport.

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The origin of the Steens-Columbia River (SCR) flood basalts, which is presumed to be the onset of Yellowstone volcanism, has remained controversial, with the proposed conceptual models involving either a mantle plume or back-arc processes. Recent tomographic inversions based on the USArray data reveal unprecedented detail of upper-mantle structures of the western USA and tightly constrain geodynamic models simulating Farallon subduction, which has been proposed to influence the Yellowstone volcanism. Here we show that the best-fitting geodynamic model depicts an episode of slab tearing about 17 million years ago under eastern Oregon, where an associated sub-slab asthenospheric upwelling thermally erodes the Farallon slab, leading to formation of a slab gap at shallow depth.

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The building of the Andes results from the subduction of the oceanic Nazca plate underneath the South American continent. However, how and why the Andes and their curvature, the Bolivian orocline, formed in the Cenozoic era (65.5 million years (Myr) ago to present), despite subduction continuing since the Mesozoic era (251.

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Mantle plumes are thought to play an important part in the Earth's tectonics, yet it has been difficult to isolate the effect that plumes have on plate motions. Here we analyse the plate motions involved in two apparently disparate events--the unusually rapid motion of India between 67 and 52 million years ago and a contemporaneous, transitory slowing of Africa's motion--and show that the events are coupled, with the common element being the position of the Indian and African plates relative to the location of the Réunion plume head. The synchroneity of these events suggests that they were both driven by the force of the Réunion plume head.

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Subduction of oceanic lithosphere occurs through two modes: subducting plate motion and trench migration. Using a global subduction zone data set and three-dimensional numerical subduction models, we show that slab width (W) controls these modes and the partitioning of subduction between them. Subducting plate velocity scales with W(2/3), whereas trench velocity scales with 1/W.

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Background: This study compared the 16-item Clinician and Self-Report versions of the Quick Inventory of Depressive Symptomatology (QIDS-C16 and QIDS-SR16) and the 10-item Montgomery-Asberg Depression Rating Scale (MADRS) in adult outpatients. The comparison was based on psychometric features and their performance in identifying those in a major depressive episode as defined by the Mini-International Neuropsychiatric Interview for Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition.

Methods: Of 278 consecutive outpatients, 181 were depressed.

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Objective: To evaluate psychometric properties and comparability ability of the Montgomery-Asberg Depression Rating Scale (MADRS) vs. the Quick Inventory of Depressive Symptomatology-Clinician-rated (QIDS-C(16)) and Self-report (QIDS-SR(16)) scales to detect a current major depressive episode in the elderly.

Method: Community and clinic subjects (age >or=60 years) were administered the Mini-International Neuropsychiatric Interview (MINI) for DSM-IV and three depression scales randomly.

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Background: Understanding patients' ambivalence about treatment persistence may be useful in tailoring retention interventions for individual patients with major depressive disorder.

Methods: Participants (n = 265) with major depressive disorder were enrolled into an 8-week trial with a selective serotonin reuptake inhibitor. At baseline and week 2, the participants were asked about their intent to return for the next visit, complete the study and continue in the study should they experience side effects or no improvement.

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The success of well-developed protocols has been limited in real-world practice, where even effective strategies have not been sufficient to meet patient needs in routine clinical care owing to Axis I and III comorbidities. The Sequenced Treatment Alternatives to Relieve Depression (STAR(*)D) trial required that antidepressant medication treatment be optimal regarding dose and duration, yet accommodate flexibility to ensure safety given the wide range of comorbid general medical and psychiatric disorders allowed in the trial. The objective of this study was to develop a measurement-based care (MBC) approach and an automated feedback system to ensure adequate and safe antidepressant treatment delivery suitable for both clinical research and routine practice.

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Subducting slabs provide the main driving force for plate motion and flow in the Earth's mantle, and geodynamic, seismic and geochemical studies offer insight into slab dynamics and subduction-induced flow. Most previous geodynamic studies treat subduction zones as either infinite in trench-parallel extent (that is, two-dimensional) or finite in width but fixed in space. Subduction zones and their associated slabs are, however, limited in lateral extent (250-7,400 km) and their three-dimensional geometry evolves over time.

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Objectives: Clinical research projects gather large amounts of data. Typically, information is captured on paper source documents for later transcription to an electronic format, where responses can be checked, and errors, omissions, and inconsistencies can be resolved. These steps contribute delays, cost, and complexity to clinical research, particularly in large-scale multi-site investigations.

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Background: The purpose of this paper is to use demographic and clinical data from a large diverse group of outpatients diagnosed with non-psychotic major depression to investigate the validity of the DSM-IV concept of melancholic depression.

Methods: Baseline clinical and demographic data were collected on 1500 outpatients (1456 of whom melancholia could be determined) with non-psychotic major depressive disorder (MDD) participating in the Sequenced Treatment Alternatives to Relieve Depression (STAR*D) study. Depressive symptom severity was assessed by clinical telephone interview using the 17-item Hamilton Rating Scale for Depression (HRS-D17) and the 30-item Inventory of Depressive Symptomatology (IDS-C30).

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The Sequenced Treatment Alternatives to Relieve Depression (STAR*D) trial is a multi-site effectiveness study funded by the National Institute of Mental Health (NIMH) with the aim of identifying successful, acceptable and cost-effective treatment strategies for outpatients with unremitted depression. With enrollment of 4,041 adults with major depressive disorder (MDD), it is the largest controlled psychiatric treatment study ever undertaken. In the course of developing procedures to ensure that ambitious enrollment goals were met, a number of ethical and practical issues became apparent that underscore the conflicts between effectiveness research and human subject protections.

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While efficient methods of communication are known to be essential in conducting large multicenter clinical trials, very little information is provided on actual methods that can be implemented to improve communication. An integrated technology-based communication system was developed for the Sequenced Treatment Alternatives to Relieve Depression (STAR*D) project, which prospectively defines treatments that are most effective for participants with a diagnosis of a nonpsychotic major depressive disorder (MDD) who report an unsatisfactory clinical outcome to an initial and, if necessary, subsequent treatment(s). This web-based communication system is comprised of a multi-faceted study Web site, including a help desk, document sharing, a project directory and reports.

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Background: Depression during pregnancy can have significant health consequences for the mother and her infant. Antidepressant medications, which pass through the placenta, may increase the risk of low birth weight and preterm delivery. The use of selective serotonin reuptake inhibitors (SSRIs) during pregnancy may induce serotonergic symptoms in the infant after delivery.

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Objective: This study examined data from the first 1,500 patients with major depressive disorder who were entered into the Sequenced Treatment Alternatives to Relieve Depression (STAR*D) and compared baseline characteristics of outpatients on the basis of their insurance status.

Methods: We compared the demographic and clinical characteristics and the features of the presenting symptoms of outpatients with private insurance, public insurance, Medicaid and Medicare, or no insurance who were seeking treatment for depression.

Results: Valid insurance data were available for 1,452 patients.

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In multicenter clinical trials, important aspects of trial performance (e.g., the number of participants who enter the trial within the required time frame, the number of participants who remain in the trial, and/or the completeness of the outcome data collected) directly affect the extent to which the study can achieve its aims.

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The efficacy and toxicity of factor VIII (FVIII) priming, cyclophosphamide immune suppression, and rapid tapering of concurrent FVIII immune tolerance for subjects with hemophilic inhibitors were evaluated. Four subjects with hemophilic inhibitors were studied. Before treatment, inhibitors were present for a median of 8 months (mean 13 +/- 14.

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In large multi-site trials, a feasibility or pilot study can be crucial to test the functionality of all aspects of conducting the study prior to the initiation of the formal study. A feasibility trial was conducted for the Sequenced Treatment Alternatives to Relieve Depression (STAR*D) Project, a multi-site, prospective, sequentially randomized, clinical trial of outpatients with nonpsychotic major depressive disorder. From 14 December 2000 to 8 June 2001, 42 patients were screened for enrollment into the STAR*D Feasibility Trial.

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Although the Moon currently has no internally generated magnetic field, palaeomagnetic data, combined with radiometric ages of Apollo samples, provide evidence for such a magnetic field from approximately 3.9 to 3.6 billion years (Gyr) ago, possibly owing to an ancient lunar dynamo.

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Acquired factor VIII (FVIII) inhibitors are rare, typically occurring in the postpartum period or in the elderly. Their occurrence in childhood is distinctly unusual. Acquired FVIII inhibitors are often life-threatening and refractory to treatment with high doses of human FVIII concentrate.

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