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Kinds of Superior Terms modified by Superior Selected AbstractsUse of paired fathead minnow (Pimephales promelas) reproductive test.ENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 7 2006Part 1: Assessing biological effects of final bleached kraft pulp mill effluent using a mobile bioassay trailer system Abstract Reproductive effects have been recorded in wild fish in waters receiving pulp mill effluent (PME) since the mid to late 1980s. Laboratory assays with fathead minnow (FHM; Pimephales promelas) have been developed to better understand fish responses to PME. However, observations from laboratory studies have been variable, making it difficult to establish cause/effect relationships. A lack of environmental relevance in these laboratory studies may have contributed to the variability observed. The objectives of the present study were, first, to determine the effects of bleached kraft PME (BKME) on FHM under environmentally realistic conditions (i.e., ambient water and effluent quality) and, second, to determine the suitability of pair-breeding FHM to better link BKME-induced changes in indicators at the biochemical, individual, and population levels. A mobile bioassay trailer was situated on-site at a bleached kraft mill for 60 d, allowing supply of both ambient water (Lake Superior, Canada) and final BKME. The reproductive output of FHM was initially assessed for 21 d to obtain baseline data pre-exposure. At the end of the pre-exposure period, selected breeding pairs were exposed to final BKME (100% v/v and 1% v/v) for 21 d. Results demonstrated a stimulatory response pattern at 1% BKME (e.g., increased egg production) compared to control. In the 100% treatment, spawning events were reduced and fewer eggs were produced during the first two weeks of exposure. Exposure to 100% (v/v) BKME also resulted in ovipositor development in males and development of male secondary sex characteristics in females. Obtaining pre-exposure data and use of pair-breeding FHM in this assay gave a sensitive indication of effluent effects and allowed accurate comparisons of endpoints to be made. [source] Spatial distribution of polychlorinated naphthalenes in air over the Great Lakes and air-water gas exchange in Lake OntarioENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 9 2003Paul A. Helm Abstract High-volume air sample were collected during research cruises of Lake Superior in August 1996 and May 1977 and of Lake Ontario (North America) in July and September 1998 and June 2000 and analyzed for polychlorinated naphthalenes (PCNs). Levels of tetra- to octachloronaphthalene (,PCN) varied spatially, with mean values (±SD) of 1.78 ± 0.74 and 1.46 ± 1.07 pg m,3 for Lake Superior in 1996 and 1997, respectively, and of 5.53 ± 2.19 and 5.60 ± 2.24 pg m,3 for Lake Ontario in 1998 and 2000, respectively. Evaporative sources were predominant, although combustion marker congeners such as tetrachloronaphthalenes 44 and 29 and pentachloronaphthalene 54 were present in most samples and were enhanced relative to technical PCN mixtures. The ,PCN concentrations were higher in Lake Ontario samples collected in the western half of the lake and when winds were from the west. Greater proportions of the population and industrial areas are located around the western part of Lake Ontario. Water-air fugacity ratios, calculated from air and water samples collected in June 2000, indicate that the trichloronaphthalenes are volatilizing from Lake Ontario, whereas the tetrachloronaphthalenes are close to equilibrium and the net deposition of tetrachloronaphthalenes can occur when the urban air plume influences levels over the lake. [source] Geoarchaeology and late glacial landscapes in the western lake superior region, Central North AmericaGEOARCHAEOLOGY: AN INTERNATIONAL JOURNAL, Issue 1 2007Christopher L. Hill The transition from full glacial to interglacial conditions along the southern margin of the Laurentide ice sheet resulted in dramatic changes in landscapes and biotic habitats. Strata and landforms resulting from the Wisconsin Episode of glaciation in the area directly west of Lake Superior indicate a context for late Pleistocene biota (including human populations) connected to ice margins, proglacial lakes, and postglacial drainage systems. Late Glacial landscape features that have the potential for revealing the presence of Paleoindian artifacts include abandoned shorelines of proglacial lakes in the Superior and Agassiz basins and interior drainages on deglaciated terrains. The linkage between Late Pleistocene human populations and Rancholabrean fauna has yet to be demonstrated in the western Lake Superior region, although isolated remains of mammoth ( Mammuthus) have been documented, as well as fluted points assigned to Clovis, Folsom, and Holcombe-like artifact forms. Agate Basin and Hell Gap (Plano-type) artifacts also imply the presence of human groups in Late Glacial landscapes associated with the Agassiz and Superior basins. © 2007 Wiley Periodicals, Inc. [source] When is Statistical Evidence Superior to Anecdotal Evidence in Supporting Probability Claims?HUMAN COMMUNICATION RESEARCH, Issue 4 2009The Role of Argument Type First page of article [source] Disc structure function and its potential for repairINTERNATIONAL JOURNAL OF RHEUMATIC DISEASES, Issue 1 2002J. Melrose The intervertebral disc (IVD) is the largest predominantly avascular, aneural, alymphatic structure of the human body. It provides articulation between adjoining vertebral bodies and also acts as a weight-bearing cushion dissipating axially applied spinal loads. The IVD is composed of an outer collagen-rich annulus fibrosus (AF) and a central proteoglycan (PG)-rich nucleus pulposus (NP). Superior and inferior cartilaginous endplates (CEPs), thin layers of hyaline-like cartilage, cover the ends of the vertebral bodies. The AF is composed of concentric layers (lamellae) which contain variable proportions of type I and II collagen, this tissue has high tensile strength. The NP in contrast is a gelatinous PG-rich tissue which provides weight-bearing properties to the composite disc structure. With the onset of age, cells in the NP progressively die as this tissue becomes depleted of PGs, less hydrated and more fibrous as the disc undergoes an age-dependent fibrocartilaginous transformation. Such age-dependent cellular and matrix changes can decrease the discs' biomechanical competence and trauma can further lead to failure of structural components of the disc. Annular defects are fairly common and include vertebral rim-lesions, concentric (circumferential) annular tears (separation of adjacent annular lamellae) and radial annular tears (clefts which initiate within the NP). While vascular in-growth around annular tears has been noted, evidence from human post-mortem studies indicate they have a limited ability to undergo repair. Several experimental approaches are currently under evaluation for their ability to promote the repair of such annular lesions. These include growth of AF fibrochondrocytes on a resorbable polycaprolactone (PCL) bio-membrane.1 Sheets of fibrochondrocytes lay down type-I collagen and actin stress fibres on PCL. These matrix components are important for the spatial assembly of the collagenous lamella during annular development and correct phenotypic expression of cells in biomatrices.1 An alternative approach employs preparation of tissue engineered IVDs where AF and NP cells are separately cultured in polyglycolic acid and sodium alginate biomatrices, either separately or within a manifold designed to reproduce the required IVD dimensions for its use as a prospective implant device.2 AF and NP cells have also been grown on tissue culture inserts after their recovery from alginate bead culture to form plugs of tissue engineered cartilage.3 A key component in this latter strategy was the stimulation of the high density disc cell cultures with osteogenic protein-1 (OP-1) 200 ng/mL.3 This resulted in the production of tissue engineered AF and NP plugs with compositions, histochemical characteristics and biomechanical properties approaching those of the native disc tissues.2,3 Such materials hold reat promise in future applications as disc or annular implants. The introduction of appropriate genes into disc cells by gene transduction methodology using adenoviral vectors or ,gene-gun' delivery systems also holds considerable promise for the promotion of disc repair processes.4 Such an approach with the OP-1 gene is particularly appealing.5 The anchoring of discal implants to vertebral bodies has also been evaluated by several approaches. A 3D fabric based polyethylene biocomposite holds much promise as one such anchorage device6 while biological glues used to seal fibrocartilaginous structures such as the AF and meniscus8 following surgical intervention, also hold promise in this area. Several very promising new experimental approaches and strategies are therefore currently under evaluation for the improvement of discal repair. The aforementioned IVD defects are a common cause of disc failure and sites of increased nerve in-growth in symptomatic IVDs in man and are thus often sources of sciatic-type pain. Annular defects such as those described above have formerly been considered incapable of undergoing spontaneous repair thus a clear need exists for interventions which might improve on their repair. Based on the rapid rate of progress and the examples outlined above one may optimistically suggest that a successful remedy to this troublesome clinical entity will be developed in the not so distant future. References 1JohnsonWEBet al. (2001) Directed cytoskeletal orientation and intervertebral disc cell growth: towards the development of annular repair techniques. Trans Orthop Res Soc26, 894. 2MizunoHet al. (2001) Tissue engineering of a composite intervertebral disc. Trans Orthop Res Soc26, 78. 3MatsumotoTet al. (2001) Formation of transplantable disc shaped tissues by nucleus pulposus and annulus fibrosus cells: biochemical and biomechanical properties. Trans Orthop Res Soc26, 897. 4NishidaKet al. (2000) Potential applications of gene therapy to the treatment of intervertebral disc disorders. Clin Orthop Rel Res379 (Suppl), S234,S241. 5MatsumotoTet al. (2001) Transfer of osteogenic protein-1 gene by gene gun system promotes matrix synthesis in bovine intervertebral disc and articular cartilage cells. Trans Orthop Res Soc26, 30. 6ShikinamiY , Kawarada (1998) Potential application of a triaxial three-dimensional fabric (3-DF) as an implant. Biomaterials19, 617,35. [source] Late-glacial and Holocene palaeovegetation zonal reconstruction for central and north-central North AmericaJOURNAL OF BIOGEOGRAPHY, Issue 6 2005W. L Strong Abstract Aim, The purpose of this study is to develop palaeovegetation zonation models for central and north-central North America, based on late-Quaternary and Holocene pollen stratigraphic data (n = 246 sites). A secondary purpose was to evaluate an hypothesis (Strong & Hills, 2003) to explain the disjunct distribution of species in western Alberta. Location, Hudson Bay-Lake Michigan to the Rocky Mountains region, north of 36° N to the Arctic Ocean (c. 70° N). Methods, Pollen profiles spanning 40 years of palaeoecological research in North America were extracted from published and unpublished archival sources. Individual profiles were subdivided into 1000-year increments based on the assumption of a constant sedimentation rate between stratigraphic dates (e.g. surface sediments, radiocarbon 14C dates, tephra layers). The pollen composition among profiles was standardized to 54 commonly recognized taxa, with percentage composition within each stratigraphic sample prorated to 100% prior to analysis. Near-surface sediments from these profiles were included as analogues of modern vegetation. Cluster analysis was used as a guide to the classification of 2356 temporal stratigraphic samples, which resulted in the recognition of 16 pollen groups. These groups were summarized in terms of their pollen composition, mapped, and used in combination with terrain information and an ecological knowledge of the study area to construct six physiognomically-based palaeovegetation zonation models at 2000-year intervals from 14,000 to 4000 yr bp (radiocarbon years before present). Results, The 14,000 yr bp model placed Boreal and Cordilleran Forests proximal to the southern glacial front, whereas Arctic tundra dominated the Yukon Territory,Alaska ice-free zone. Pollen and macrofossil evidence suggests that this Boreal Forest zone contained a mixture of coniferous and deciduous tree species. Grassland was postulated immediately south of the forest zone, with its northern extreme near 49° N latitude in the Alberta,Montana border area. Separation of the Laurentide and Cordilleran glacial fronts about 12,000 yr bp initiated the northward advance of Boreal Forests into western Canada. By the end of the Hypsithermal at about 6000 yr bp, Boreal Forests occurred near the Arctic Ocean, and Grassland and Aspen Parkland zones may have extended to 54° N and 59° N latitude in Alberta, respectively. Between 6000 and 4000 yr bp, a 5° and 1° latitudinal southward shift of the northern Boreal Forest and Grassland/Aspen Parkland boundaries occurred, respectively, near their contemporary positions with corresponding expansions of the Subarctic and Arctic zones. Modern Canadian Cordilleran Forests along the eastern slopes of the Rocky Mountains were interpreted as originating from the north-central Montana,south-western Alberta area. Jack pine (Pinus banksiana Lamb.), a common Boreal Forest species, appears to have entered central Canada via the north side of Lake Superior after 11,000 yr bp. Main conclusions, Modern vegetation in central Canada evolved from biomes located in the northern USA during the late-Quaternary. The Boreal Forest biome contained the same arboreal taxa as the modern vegetation, except it lacked jack pine. The proposed regional palaeovegetation models support the hypothesis of Strong & Hills (2003), but new independent palaeoecological data will be needed for a proper evaluation. [source] Biocompatibility of Heparin-Coated Cardiopulmonary Bypass Circuits in Coronary Patients With Left Ventricular Dysfunction Is Superior to PMEA-Coated CircuitsJOURNAL OF CARDIAC SURGERY, Issue 6 2006Veysel Kutay M.D. The aim of this study was to evaluate the clinical effectiveness and biocompatibility of heparin-coated and poly-2-methoxyethylacrylate (PMEA)-coated CPB circuits on coronary patients with left ventricular systolic dysfunction. Methods: Thirty-six patients who underwent elective coronary artery bypass grafting were divided into two equal groups: group H (n = 18), heparin-coated; group P (n = 18), PMEA coated. Clinical outcomes, hematologic variables, cardiac enzymes, malondialdehyde (MDA), and acute phase inflammatory response (including myeloperoxidase (MPO), catalase, hsCRP, and IL-8) were analyzed perioperatively. Results: Demographic, CPB, and clinical outcome data were similar for both groups. Plasma fibrinogen, total protein, albumin, and platelet count decreased, neutrophil count, MDA, IL-8, MPO, and catalase levels increased during CPB. During CPB, MPO and catalase values were significantly higher in group P (p = 0.02 and p = 0.01) and postoperative MDA concentration was lower in group H (p = 0.03). Platelet counts were better preserved in group H during and after CPB but neutrophil count and IL-8 level did not differ between the groups. Postoperative total protein, albumin, and fibrinogen levels were higher in group H (p < 0.05). The postoperative first day levels of troponin-I, CK-MB, and CRP increased in both groups without any significant differences between the groups. Conclusions: Heparin-coated circuit provided better suppression of perioperative inflammatory markers and exhibited more favorable effects on hematologic variables than PMEA-coated circuit. [source] Exercise is Superior to Pacing for T Wave Alternans Measurement in Subjects with Chronic Coronary Artery Disease and Left Ventricular DysfunctionJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 9 2002ERIC J. RASHBA M.D. Exercise vs Pacing for TWA Measurement.Introduction: T wave alternans (TWA) is a heart rate-dependent marker of vulnerability to ventricular arrhythmias. Atrial pacing and exercise both are used as provocative stimuli to elicit TWA. However, the prognostic value of the two testing methods has not been compared. The aim of this prospective study was to compare the prognostic value of TWA measured during bicycle exercise and atrial pacing in a large cohort of high-risk patients with ischemic heart disease and left ventricular dysfunction. Methods and Results: This was a prospective study of 251 patients with coronary artery disease and left ventricular dysfunction who were referred for electrophysiologic studies (EPS) for standard clinical indications. Patients underwent TWA testing using bicycle ergometry (exercise TWA, n = 144) and/or atrial pacing (pacing TWA, n = 178). The primary endpoint was the combined incidence of death, sustained ventricular arrhythmias, and appropriate implantable cardioverter defibrillator therapy. The predictive value of exercise and pacing TWA for EPS results and for endpoint events was determined. Exercise and pacing TWA both were significant predictors of EPS results (odds ratios 3.0 and 2.9 respectively, P < 0.02). Kaplan-Meier survival analysis of the primary endpoint revealed that exercise TWA was a significant predictor of events (hazard ratio 2.2, P = 0.03). In contrast, pacing TWA had no prognostic value for endpoint events (hazard ratio 1.1, P = 0.8). Conclusion: TWA should be measured during exercise when it is used for clinical risk stratification. EPS results may not be an adequate surrogate for spontaneous events when evaluating new risk stratification tests. [source] Electrical Connection Between Left Superior and Inferior Pulmonary Veins in a Patient with Paroxysmal Atrial FibrillationJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 5 2002YOSHIHIDE TAKAHASHI M.D. Electrical Connection Between Pulmonary Veins. We report the case of a patient with paroxysmal atrial fibrillation, who underwent pulmonary vein (PV) electrical isolation from the left atrium (LA). Prior to achieving isolation of the left superior PV (LSPV) from the LA, earlier PV potentials were recorded inside the left inferior PV (LIPV) than LA activity during pacing at the distal LSPV. The LSPV finally was isolated by radiofrequency applications at the ostium of the LIPV. The patient had electrical connection between the LSPV and LIPV, and required radiofrequency ablation of the breakthroughs from the LA to LIPV for complete isolation of the LSPV. [source] The effect of Coca-Cola and fruit juices on the surface hardness of glass,ionomers and ,compomers'JOURNAL OF ORAL REHABILITATION, Issue 11 2004M. Aliping-McKenzie summary, The interaction of tooth-coloured dental restorative materials (a conventional glass,ionomer, two resin-modified glass,ionomers and two compomers) with acidic beverages has been studied with the aim of investigating how long-term contact affects solution pH and specimen surface hardness. For each material (ChemFil Superior, ChemFlex, Vitremer Core Build-Up/Restorative, Fuji II LC, Dyract AP and F2000) disc-shaped specimens were prepared and stored in sets of six in the following storage media: 0·9% NaCl (control), Coca-Cola, apple juice and orange juice. After time intervals of 1 day, 1 week, 1 month, 3 months, 4 months, 6 months and 1 year, solution pH and Vickers Hardness Number were determined for each individual specimen. Differences were analysed by anova followed by Student,Newman,Keuls post hoc analysis. All materials were found to reduce the pH of the 0·9% NaCl, but to increase the pH of the acidic beverages. The conventional glass,ionomers dissolved completely in apple juice and orange juice, but survived in Coca-Cola, albeit with a significantly reduced hardness after 1 year. The other materials survived in apple juice and orange juice, but showed greater reductions in surface hardness in these beverages than in Coca-Cola. Fruit juices were thus shown to pose a greater erosive threat to tooth coloured materials than Coca-Cola, a finding which is similar to those concerning dentine and enamel towards these drinks. [source] Lower fitness of hatchery and hybrid rainbow trout compared to naturalized populations in Lake Superior tributariesMOLECULAR ECOLOGY, Issue 11 2004L. M. MILLER Abstract We have documented an early life survival advantage by naturalized populations of anadromous rainbow trout Oncorhynchus mykiss over a more recently introduced hatchery population and outbreeding depression resulting from interbreeding between the two strains. We tested the hypothesis that offspring of naturalized and hatchery trout, and reciprocal hybrid crosses, survive equally from fry to age 1+ in isolated reaches of Lake Superior tributary streams in Minnesota. Over the first summer, offspring of naturalized females had significantly greater survival than offspring of hatchery females in three of four comparisons (two streams and 2 years of stocking). Having an entire naturalized genome, not just a naturalized mother, was important for survival over the first winter. Naturalized offspring outperformed all others in survival to age 1+ and hybrids had reduced, but intermediate, survival relative to the two pure crosses. Averaging over years and streams, survival relative to naturalized offspring was 0.59 for hybrids with naturalized females, 0.37 for the reciprocal hybrids, and 0.21 for hatchery offspring. Our results indicate that naturalized rainbow trout are better adapted to the conditions of Minnesota's tributaries to Lake Superior so that they outperform the hatchery-propagated strain in the same manner that many native populations of salmonids outperform hatchery or transplanted fish. Continued stocking of the hatchery fish may conflict with a management goal of sustaining the naturalized populations. [source] Magnetic Resonance Imaging is Superior to Cardiac Scintigraphy to Identify Nonresponders to Cardiac Resynchronization TherapyPACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 2009MIKI YOKOKAWA M.D. Background: Left ventricular (LV) postero-lateral scar and total scar burden are factors responsible for a poor response to cardiac resynchronization therapy (CRT). Contrast-enhanced magnetic resonance imaging (CMR) and 99mTc-2-methoxy isobutyl isonitrile single photon emission computed tomography (SPECT) perfusion imaging are widely used to detect myocardial scar tissue; however, their ability to detect regional scars and predict a positive response to CRT has not been fully evaluated. Methods: CMR and SPECT were performed in 17 patients with dilated cardiomyopathy (DCM) and seven patients with ischemic cardiomyopathy (ICM) before CRT. All images were scored, using a 17-segment model. To analyze the LV scar regions by CMR, we assessed the transmural delayed enhancement extent as the transmural score in each segment (0 = no scar, 4 = transmural scar). Similarly, a perfusion defect score was assigned to each segment by SPECT (0 = normal uptake, 4 = defect). Results: By both SPECT and CMR imaging, the total scar score was significantly higher in the ICM than in the DCM group. An LV postero-lateral wall scar region was detected using both imaging modes. By SPECT imaging, the percentage of regional scar score in the LV inferior wall was significantly higher in the DCM than in the ICM group. Conclusions: By SPECT imaging in the DCM group, severe perfusion defects, due to attenuation artifacts, were frequently observed in the LV inferior wall, resulting in the overestimation of scar tissue. CMR identified nonresponders to CRT more reliably than SPECT in patients with DCM. [source] The Future City on the Inland Sea: A History of Imaginative Geographies of Lake Superior by Eric D. OlmansonTHE JOURNAL OF AMERICAN CULTURE, Issue 4 2007Ray B. Browne No abstract is available for this article. [source] Scoring Total Inflammation Is Superior to the Current Banff Inflammation Score in Predicting Outcome and the Degree of Molecular Disturbance in Renal AllograftsAMERICAN JOURNAL OF TRANSPLANTATION, Issue 8 2009M. Mengel Emerging molecular analysis can be used as an objective and independent assessment of histopathological scoring systems. We compared the existing Banff i-score to the total inflammation (total i-) score for assessing the molecular phenotype in 129 renal allograft biopsies for cause. The total i-score showed stronger correlations with microarray-based gene sets representing major biological processes during allograft rejection. Receiver operating characteristic curves showed that total-i was superior (areas under the curves 0.85 vs. 0.73 for Banff i-score, p = 0.012) at assessing an abnormal cytotoxic T-cell burden, because it identified molecular disturbances in biopsies with advanced scarring. The total-i score was also a better predictor of graft survival than the Banff i-score and essentially all current diagnostic Banff categories. The exception was antibody-mediated rejection which is able to predict graft loss with greater specificity (96%) but at low sensitivity (38%) due to the fact that it only applies to cases with this diagnosis. The total i-score is able to achieve moderate sensitivities (60,80%) with losses in specificity (60,80%) across the whole population. Thus, the total i-score is superior to the current Banff i-score and most diagnostic Banff categories in predicting outcome and assessing the molecular phenotype of renal allografts. [source] Is Rhythm-Control Superior to Rate-Control in Patients with Atrial Fibrillation and Diastolic Heart Failure?ANNALS OF NONINVASIVE ELECTROCARDIOLOGY, Issue 3 2010Melissa H. Kong M.D. Background: Although no clinical trial data exist on the optimal management of atrial fibrillation (AF) in patients with diastolic heart failure, it has been hypothesized that rhythm-control is more advantageous than rate-control due to the dependence of these patients' left ventricular filling on atrial contraction. We aimed to determine whether patients with AF and heart failure with preserved ejection fraction (EF) survive longer with rhythm versus rate-control strategy. Methods: The Duke Cardiovascular Disease Database was queried to identify patients with EF > 50%, heart failure symptoms and AF between January 1,1995 and June 30, 2005. We compared baseline characteristics and survival of patients managed with rate- versus rhythm-control strategies. Using a 60-day landmark view, Kaplan-Meier curves were generated and results were adjusted for baseline differences using Cox proportional hazards modeling. Results: Three hundred eighty-two patients met the inclusion criteria (285 treated with rate-control and 97 treated with rhythm-control). The 1-, 3-, and 5-year survival rates were 93.2%, 69.3%, and 56.8%, respectively in rate-controlled patients and 94.8%, 78.0%, and 59.9%, respectively in rhythm-controlled patients (P > 0.10). After adjustments for baseline differences, no significant difference in mortality was detected (hazard ratio for rhythm-control vs rate-control = 0.696, 95% CI 0.453,1.07, P = 0.098). Conclusions: Based on our observational data, rhythm-control seems to offer no survival advantage over rate-control in patients with heart failure and preserved EF. Randomized clinical trials are needed to verify these findings and examine the effect of each strategy on stroke risk, heart failure decompensation, and quality of life. Ann Noninvasive Electrocardiol 2010;15(3):209,217 [source] ROCK SURFACE HARDNESS AS AN INDICATION OF EXPOSURE AGE: AN ARCHAEOLOGICAL APPLICATION OF THE SCHMIDT HAMMER,ARCHAEOMETRY, Issue 1 2000M. W. BETTS A Schmidt Hammer was employed in evaluating the surface hardness of rocks which line ancient anthropogenic pit features, known as Pukaskwa pits, on the north shore of Lake Superior, Canada. This technique offers a possible new method of producing relative ana absolute dates for such exposed stone features Analysis of the data has provided a relative chronology for the pit features, representing two distinct construction phases. The range of absolute dates generated from the data indicates that the pits were likely constructed by Blackduck peoples c. 900 to 400 years BP. [source] AUTHORSHIP AND IDENTITY IN MAX ERNST'S LOPLOPART HISTORY, Issue 3 2005Samantha Kavky From 1928 to 1932 an avian creature named Loplop, Bird Superior, appears regularly in the collages and paintings of the surrealist artist Max Ernst. In this article I suggest that Ernst models Loplop on the father/totem, as defined by Sigmund Freud in his Totem and Taboo of 1913. An exploration of Ernst's interpretation of Freudian theory in creating Loplop illuminates the character's surprising complexity and centrality to Ernst's oeuvre. As a totem, Loplop emerges from a primary oedipal conflict on which Ernst structures his artistic identity and practice. Equating traditional notions of creative authorship with various forms of patriarchal authority, Ernst's constructed totem signifies his personal, aesthetic and political rejection of individual mastery in favour of his fraternal allegiance to the surrealist group and his embrace of surrealist automatist practices. [source] Hudson Strait ice streams: a review of stratigraphy, chronology and links with North Atlantic Heinrich eventsBOREAS, Issue 1 2003John T. Andrews We review the literature on the occupation of Hudson Strait (800 km long by 90 km wide) by late Quaternary ice streams, and the importance of Hudson Strait as the major source for sediments associated with the North Atlantic Heinrich (H-) events. Glacial erosion of the Paleozoic outcrop on the floor of Hudson Strait and Ungava Bay resulted in the export of detrital carbonate-rich sediments to ice-proximal locations on the slope and floor of the NW Labrador Sea, mainly in meltwater and turbidite plumes, and to ice distal sites thousands of kilometres away largely as iceberg-rafted detritus (IRD). Erosion of bedrock from the Precambrian Superior and Churchill provenances of the Canadian Shield is also indicated by the isotopic analyses of sediments. The major late Quaternary H-events (H-4, H-2 and H-1) are represented in southeast Baffin Island slope sediments as detrital carbonate-rich intervals up to 40 cm in thickness and appear to represent flow along the axis of the Strait. However, the late marine isotope stage #3 event, H-3 (,27 ka), and a younger event (H-0, ,11 ka), are not as dominant in the sedimentary record and probably represent a different glaciological regime with flow across Hudson Strait from eastern Ungava-Labrador. The freezing-on of sediments by supercooling in the rise from the 900 m deep Eastern Basin to the 400 m sill is proposed as the source of the abundant carbonate-rich glaciomarine sediments some 250 km from the outcrop in Eastern Basin. Sediment transport by meltwater and turbidity currents was the major process during H-events in ice-proximal settings. IRD was not a key diagnostic process at sites fronting Hudson Strait. A key feature in the instability of this ice stream might be the great depth (600 m) at the shelf break, and the deep basin, which lies seaward of the outer Hudson Strait sill. [source] Growth hormone in short children: medically appropriate treatmentACTA PAEDIATRICA, Issue 1 2001R Macklin Bolt and Mul argue persuasively against the "disease" approach and the "client" approach in addressing the question of whether growth hormone for short children properly belongs in the medical realm. Their own preferred approach, the "suffering" approach, is superior to the others but has practical problems that would arise in its application. An additional ethical issue, not addressed by Bolt and Mul, relates to justice in providing access for children from families of limited financial means to growth hormone treatment. [source] Near-Term Travel Speed Prediction Utilizing Hilbert,Huang TransformCOMPUTER-AIDED CIVIL AND INFRASTRUCTURE ENGINEERING, Issue 8 2009Khaled Hamad In this study, we propose an innovative methodology for such prediction. Because of the inherently direct derivation of travel time from speed data, the study was limited to the use of speed only as a single predictor. The proposed method is a hybrid one that combines the use of the empirical mode decomposition (EMD) and a multilayer feedforward neural network with backpropagation. The EMD is the key part of the Hilbert,Huang transform, which is a newly developed method at NASA for the analysis of nonstationary, nonlinear time series. The rationale for using the EMD is that because of the highly nonlinear and nonstationary nature of link speed series, by decomposing the time series into its basic components, more accurate forecasts would be obtained. We demonstrated the effectiveness of the proposed method by applying it to real-life loop detector data obtained from I-66 in Fairfax, Virginia. The prediction performance of the proposed method was found to be superior to previous forecasting techniques. Rigorous testing of the distribution of prediction errors revealed that the model produced unbiased predictions of speeds. The superiority of the proposed model was also verified during peak periods, midday, and night. In general, the method was accurate, computationally efficient, easy to implement in a field environment, and applicable to forecasting other traffic parameters. [source] Identification of Time-Variant Modal Parameters Using Time-Varying Autoregressive with Exogenous Input and Low-Order Polynomial FunctionCOMPUTER-AIDED CIVIL AND INFRASTRUCTURE ENGINEERING, Issue 7 2009C. S. Huang By developing the equivalent relations between the equation of motion of a time-varying structural system and the TVARX model, this work proves that instantaneous modal parameters of a time-varying system can be directly estimated from the TVARX model coefficients established from displacement responses. A moving least-squares technique incorporating polynomial basis functions is adopted to approximate the coefficient functions of the TVARX model. The coefficient functions of the TVARX model are represented by polynomials having time-dependent coefficients, instead of constant coefficients as in traditional basis function expansion approaches, so that only low orders of polynomial basis functions are needed. Numerical studies are carried out to investigate the effects of parameters in the proposed approach on accurately determining instantaneous modal parameters. Numerical analyses also demonstrate that the proposed approach is superior to some published techniques (i.e., recursive technique with a forgetting factor, traditional basis function expansion approach, and weighted basis function expansion approach) in accurately estimating instantaneous modal parameters of a structure. Finally, the proposed approach is applied to process measured data for a frame specimen subjected to a series of base excitations in shaking table tests. The specimen was damaged during testing. The identified instantaneous modal parameters are consistent with observed physical phenomena. [source] Optimizing process allocation of parallel programs for heterogeneous clustersCONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 4 2009Shuichi Ichikawa Abstract The performance of a conventional parallel application is often degraded by load-imbalance on heterogeneous clusters. Although it is simple to invoke multiple processes on fast processing elements to alleviate load-imbalance, the optimal process allocation is not obvious. Kishimoto and Ichikawa presented performance models for high-performance Linpack (HPL), with which the sub-optimal configurations of heterogeneous clusters were actually estimated. Their results on HPL are encouraging, whereas their approach is not yet verified with other applications. This study presents some enhancements of Kishimoto's scheme, which are evaluated with four typical scientific applications: computational fluid dynamics (CFD), finite-element method (FEM), HPL (linear algebraic system), and fast Fourier transform (FFT). According to our experiments, our new models (NP-T models) are superior to Kishimoto's models, particularly when the non-negative least squares method is used for parameter extraction. The average errors of the derived models were 0.2% for the CFD benchmark, 2% for the FEM benchmark, 1% for HPL, and 28% for the FFT benchmark. This study also emphasizes the importance of predictability in clusters, listing practical examples derived from our study. Copyright © 2008 John Wiley & Sons, Ltd. [source] Persistence of Left Supracardinal Vein in an Adult Patient with Heart,Hand Syndrome and Cardiac PacemakerCONGENITAL HEART DISEASE, Issue 3 2008Jan Nemec MD ABSTRACT A patient with a sporadic heart,hand syndrome, which includes thumb hypoplasia, septum primum atrial septal defect, and cleft mitral valve is described. During attempted placement of a pacemaker lead, persistence of left superior and inferior vena cava was found in addition to the right-sided caval veins. This corresponds to persistence of left-sided supracardinal vein present during fetal development. [source] Validity and ethics of the human 4-h patch test as an alternative method to assess acute skin irritation potentialCONTACT DERMATITIS, Issue 1 2001Michael K. Robinson For more than 50 years, the Draize rabbit skin irritation test has reigned supreme as the regulatory method of choice for the identification of skin irritant chemicals. To date no in vitro alternative test has been validated as an adequate replacement. However, one potential option, to test the endpoint of concern (skin irritation) in the species of concern (man) has been overlooked. The advent of predictive in vitro tools for the identification of substances corrosive to the skin has opened up the practical possibility of carrying out safe and ethical studies on small panels of humans. The human 4-h patch test has been developed to meet the needs of identifying chemical skin irritation potential, providing data which is inherently superior to that given by a surrogate model, such as the rabbit. This paper reviews in detail the present state of the human 4-h patch test, highlighting its advantages and noting its utility as the ,gold standard' on which to build future in vitro models. [source] The treatment of CIN: what are the risks?CYTOPATHOLOGY, Issue 3 2009W. Prendiville The treatment of squamous cervical intraepithelial neoplasia is to remove or destroy the transformation zone (TZ). It is likely that no method of treatment is superior to another if it is performed properly and the limited available evidence supports this view. The significant advantages of excision (simplicity, cost, outpatient procedure, histological examination of the entire TZ) mean that treatment thresholds may have lowered over the last decade. Long-term pregnancy-related morbidity associated with excision has been reported recently. The evidence would suggest that this increase equates to a genuine increase in serious adverse outcome for cone biopsy but not large loop excision of the transformation zone (LLETZ). The available data also point to an increase in both incomplete excision and premature labour associated with the excision of large endocervical TZs. The clinical implications arising from this are firstly that women with large type 2 and 3 TZs need appropriate counselling before treatment and that the threshold for treating young women with mild abnormalities needs review. [source] A Comparison of Arbitration Procedures for Risk-Averse Disputants,DECISION SCIENCES, Issue 4 2004Michael J. Armstrong ABSTRACT We propose an arbitration model framework that generalizes many previous quantitative models of final offer arbitration, conventional arbitration, and some proposed alternatives to them. Our model allows the two disputants to be risk averse and assumes that the issue(s) in dispute can be summarized by a single quantifiable value. We compare the performance of the different arbitration procedures by analyzing the gap between the disputants' equilibrium offers and the width of the contract zone that these offers imply. Our results suggest that final offer arbitration should give results superior to those of conventional arbitration. [source] e-Integration in the Supply Chain: Barriers and Performance,DECISION SCIENCES, Issue 4 2002Markham T. Frohlich ABSTRACT Current opinion holds that Internet-based supply chain integration with upstream suppliers and downstream customers (called "e-integration" in this paper) is superior to traditional ways of doing business. This proposition remains untested, however, and similarly we know little about what are the upstream, internal, and downstream barriers to implementing e-integration. This paper empirically addressed these questions using data from a large single nation study, and found (1) a positive link between e-integration and performance, and (2) that internal barriers impeded e-integration more than either upstream supplier barriers or downstream customer barriers. Findings from this study contribute to our theoretical understanding of implementing change in contemporary supply chains, and have important implications for manufacturers interested in improving their supply chain's performance using the Internet. [source] Economic Production Lot Sizing with Periodic Costs and Overtime,DECISION SCIENCES, Issue 3 2001E. Powell Robinson Jr Abstract Traditional approaches for modeling economic production lot-sizing problems assume that a single, fixed equipment setup cost is incurred each time a product is run, regardless of the quantity manufactured. This permits multiple days of production from one production setup. In this paper, we extend the model to consider additional fixed charges, such as cleanup or inspection costs, that are associated with each time period's production. This manufacturing cost structure is common in the food, chemical, and pharmaceutical industries, where process equipment must be sanitized between item changeovers and at the end of each day's production. We propose two mathematical problem formulations and optimization algorithms. The models' unique features include regular time production constraints, a fixed charge for each time period's production, and the availability of overtime production capacity. Experimental results indicate the conditions under which our algorithms' performance is superior to traditional approaches. We also test the procedures on a set of lot-sizing problems facing a national food processor and document their potential economic benefit. [source] Comparison of acidic fibroblast growth factor on collagen carrier with calcium hydroxide as pulp capping agents in monkeysDENTAL TRAUMATOLOGY, Issue 5 2007Zhimei Li Abstract,,, Acidic fibroblast growth factor (aFGF) has been shown to facilitate wound healing by stimulating fibroblast proliferation and angiogenesis. It has also been reported to possess a powerful anti-apoptotic function This study compared the histological pulp responses to aFGF on collagen carrier and Ca(OH)2 placed on the mechanically exposed dental pulp in monkeys at two observation periods. Thirty-six teeth with pulp exposures were distributed into three groups according to the capping agents used prior to application of the coronal seal: collagen-based matrix carrier (group 1), aFGF on the collagen-based matrix carrier (group 2) and aqueous calcium hydroxide [Ca(OH)2] paste (group 3). Specimens were harvested at 6 and 13 weeks postoperatively and prepared for hematoxylin and eosin, and Gram staining. Histological qualitative evaluation of pulp responses were performed under the light microscope following criteria modified from Cox et al. (17) and Hu et al. (18). Semi-quantitative analysis was also carried out using Kruskal,Wallis and Mann,Whitney U -tests. There was neither negligible inflammatory infiltrates with no bacteria present in the three groups at both timings, nor was there any significant difference in the soft tissue organization among the three groups at or between the 6- and 13-week observation periods. At 6 weeks, the hard tissue barrier produced by Ca(OH)2 group (1.040 ± 0.089) was significantly more superior than aFGF/collagen carrier group (1.930 ± 0.825) (P = 0.030) as well as collagen carrier group (3.142 ± 1.069, P = 0.018). At 13 weeks, both aFGF/collagen carrier group (1.214 ± 0.485) and the collagen carrier group (1.457 ± 0.814) produced significantly better hard tissue barrier (P = 0.040 and P = 0.017, respectively) than earlier timing. However, these two groups did not induce significantly improved hard tissue barrier compared to that produced by aqueous Ca(OH)2 paste which stimulated matrix secretion in a polar tubular dentin-like pattern. [source] Prevalence of oral trauma in children with bilateral cleftsDENTAL TRAUMATOLOGY, Issue 1 2005Juliana Yassue Barbosa Da Silva Abstract,,, The main object of this study is to analyze the prevalence of oral trauma in subjects with complete bilateral clefts, with anterior projection of the premaxilla. A total of 106 children aging 6 months to 9 years were analyzed. The caretakers answered a specific questionnaire, in order to report the presence or absence of trauma to the soft and/or hard tissues of the child's mouth. Whenever there was a history of trauma, the patients were submitted to clinical examination. The prevalence of oral trauma was 53%, being 91% of soft tissue lesions, 8.9% of avulsion, 7% of luxation and 1.8% of intrusion. For the males, the prevalence was 56% and for the females it was 47%, with no statistical significance. Regarding the following aspects:period of time spent with the parents and at school, and presence or absence of siblings, no statistical difference could be found. Among the traumatized individuals, 80% aged less than 3 years by the moment of the trauma, 89% suffered the trauma at home, 75% presented lesions in the soft tissue at the premaxilla, 16% in the maxillary incisors, and 8.9% presented lesions in both structures. It was noticed that 45% of the permanent incisors that succeeded the traumatized deciduous teeth presented alterations, being 48% of structure and 52% of structure and position. The prevalence of trauma in this sample was superior to that observed in the literature, without any positive associations between the evaluated aspects. These results suggest that the projection of the premaxilla brings about a higher risk of oral trauma around this area. 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