Late Quaternary Marine and Terrestrial Environments, Northwestern Baffin Island, Northwest Territories

Paleoenvironmental data were analyzed from terrestrial, lake, and marine sediments collected near Arctic Bay, Baffin Island, N.W.T. Eighteen new radiocarbon dates provide chronological control, superseding earlier results. Spuriously old dates were obtained from both sandy peats and low-organic lake sediments. The most reliable dates were from marine shells and foraminifera. They indicate that déglaciation was underway by 9000 BP rather than 16,000 BP. Over the period of the record, the local environment was characterized by a high arctic pollen assemblage dominated by grass, sedge, and willow; a middle Holocene warm period is indicated by increased willow, herb, and moss values. Sea-ice conditions were severe enough to inhibit the growth of diatoms until ca. 6300 BP and ice proximal and deglacial conditions prevailed in the fiords until ca. 6000 BP. Diatom productivity increased between 3000 BP and 2500 BP, suggesting warmer surface waters and less sea ice. After 2000 BP diatom accumulation decreased sharply, due to a cooling of climate. The foraminifera indicate a major change in bottom water conditions ca. 4000 BP as the benthic species shift from a calcareous to an arenaceous assemblage.On a procédé à l'analyse des données paléoenvironnementales tirées de sédiments terrestres, marins et lacustres, près de Arctic Bay. Dix-huit nouvelles dates au radiocarbone ont permis d'établir une nouvelle chronologie. Les dates les plus anciennes, et les moins fiables, ont été obtenus dans des tourbes sableuses et des sédiments lacustres à basse teneur organique. Les dates les plus sûres proviennent de coquillages marins et des foraminifères. Elles indiquent que la déglaciation était en cours dès 9000 BP plutôt qu'à 16 000 BP. Pendant la période relevée, l'environnement dans le haut Arctique était caractérisé au niveau local par un assemblage pollinique dominé par l'herbe, le carex et le saule; à l'Holocène moyen, les valeurs croissantes du saule, de l'herbe et de la mousse reflètent une période chaude. La densité de la glace marine était assez forte pour empêcher la croissance des diatomées jusqu'à 6300 BP; la déglaciation s'est poursuivie jusque vers 6000 BP dans les fjords. La reproduction des diatomées a augmenté entre 3000 et 2500 BP en raison de températures de surface plus chaudes et une diminution des glaces marines. Après 2000 BP, l'accumulation des diatomées a décru abruptement en raison d'un refroidissement climatique. Les foraminifères démontrent un changement important survenu dans l'état des eaux profondes vers 4000 BP puisqu'il y a eu remplacement des espèces benthoniques à test calcaire par des espèces à test agglutiné.Man hat Palâoumweltdaten von Erd-, See- und Meeres-Sedimenten analysiert, die man in der Nâhe der Arctic Bay, lnsel Baffin, Nordwest-Territorien gesammelt hat. Achtzehn neue Radiocarbondaten liefern eine chronologische Kontrolle und ersetzen so fruhere Resultate. Faische alte Daten hat man sowohi aus sandigem Ton1 wie auch aus Seesedimenten mit niedrigem organischem Gehalt gewonnen. Die zuver-làssigsten Daten stammen von Meeres-muscheln und Foraminiferen. Sie zeigen, dass die Enteisung urn 9000 v.u.Z. und nicht um 16,000 v.u.Z. im Gange war. Liber den Zeitraum des Belegs charakterisierte sich die lokale Umwelt durch eine Pollen-Zusammensetzung der hohen Arktis, die von Gras, Schilfgras und Weide beherrscht war; auf eine warme Période wâhrend des mittleren Holozàns weisen zunehmende Weiden-, Gras- und Mooswerte. Die Meereseisbedingungen waren streng genug, um das Wachstum von Diatomeen bis etwa 6300 v.u.Z. zu verhindern und Proximaleis und Enteisungsbedingungen herrschten in den Fjords bis etwa 6000 v.u.Z. vor. Die Reproduktion von Diatomeen nahm zwischen 3000 v.u.Z. und 2500 v.u.Z. zu, was auf wàrmeres Oberflàchenwasser und weniger Meereseis schliessen làsst. Nach 2000 v.u.Z. nahm die Diatomeen-Akkumulation wegen einer Klimaabkuhlung plôtzlich ab. Die Foraminiferen zeigen einen betràchtlichen Wechsel der Bedingungen im tiefen Wasser um etwa 4000 v.u.Z., wenn die benthonischen Spezies von einer kalkartigen zu einer sandigen Zusammensetzung ubergehen

Performance Measures Using Electronic Health Records: Five Case Studies

Presents the experiences of five provider organizations in developing, testing, and implementing four types of electronic quality-of-care indicators based on EHR data. Discusses challenges, and compares results with those from traditional indicators

Csm4, in Collaboration with Ndj1, Mediates Telomere-Led Chromosome Dynamics and Recombination during Yeast Meiosis

Chromosome movements are a general feature of mid-prophase of meiosis. In budding yeast, meiotic chromosomes exhibit dynamic movements, led by nuclear envelope (NE)-associated telomeres, throughout the zygotene and pachytene stages. Zygotene motion underlies the global tendency for colocalization of NE-associated chromosome ends in a “bouquet.” In this study, we identify Csm4 as a new molecular participant in these processes and show that, unlike the two previously identified components, Ndj1 and Mps3, Csm4 is not required for meiosis-specific telomere/NE association. Instead, it acts to couple telomere/NE ensembles to a force generation mechanism. Mutants lacking Csm4 and/or Ndj1 display the following closely related phenotypes: (i) elevated crossover (CO) frequencies and decreased CO interference without abrogation of normal pathways; (ii) delayed progression of recombination, and recombination-coupled chromosome morphogenesis, with resulting delays in the MI division; and (iii) nondisjunction of homologs at the MI division for some reason other than absence of (the obligatory) CO(s). The recombination effects are discussed in the context of a model where the underlying defect is chromosome movement, the absence of which results in persistence of inappropriate chromosome relationships that, in turn, results in the observed mutant phenotypes

Reflecting on loss in Papua New Guinea

This article takes up the conundrum of conducting anthropological fieldwork with people who claim that they have 'lost their culture,' as is the case with Suau people in the Massim region of Papua New Guinea. But rather than claiming culture loss as a process of dispossession, Suau claim it as a consequence of their own attempts to engage with colonial interests. Suau appear to have responded to missionization and their close proximity to the colonial-era capital by jettisoning many of the practices characteristic of Massim societies, now identified as 'kastom.' The rejection of kastom in order to facilitate their relations with Europeans during colonialism, followed by the mourning for kastom after independence, both invite consideration of a kind of reflexivity that requires action based on the presumed perspective of another

The Massive Progenitor of the Possible Type II-Linear Supernova 2009hd in Messier 66

We present observations of SN2009hd in the nearby galaxy M66. This SN is one of the closest to us in recent years but heavily obscured by dust, rendering it unusually faint in the optical, given its proximity. We find that the observed properties of SN2009hd support its classification as a possible Type II-L SN, a relatively rare subclass of CC-SNe. High-precision relative astrometry has been employed to attempt to identify a SN progenitor candidate, based on a pixel-by-pixel comparison between HST F555W and F814W images of the SN site prior to explosion and at late times. A progenitor candidate is identified in the F814W images only; this object is undetected in F555W. Significant uncertainty exists in the astrometry, such that we cannot definitively identify this object as the SN progenitor. Via insertion of artificial stars into the pre-SN HST images, we are able to constrain the progenitor's properties to those of a possible supergiant, with M(F555W)0>-7.6 mag and (V-I) 0>0.99 mag. The magnitude and color limits are consistent with a luminous RSG; however, they also allow for the possibility that the star could have been more yellow than red. From a comparison with theoretical massive-star evolutionary tracks, which include rotation and pulsationally enhanced mass loss, we can place a conservative upper limit on the initial mass for the progenitor of <20 M_sun. If the actual mass of the progenitor is near the upper range allowed by our derived mass limit, then it would be consistent with that for the identified progenitors of the SNII-L 2009kr and the high-luminosity SNII-P 2008cn. The progenitors of these three SNe may possibly bridge the gap between lower-mass RSG that explode as SNeII-P and LBV, or more extreme RSG, from which the more exotic SNeII-n may arise. Very late-time imaging of the SN2009hd site may provide us with more clues regarding the true nature of its progenitor.Comment: 19 pages, 9 figures, 3 tables, accepted for publication in Ap

What do evidence-based secondary journals tell us about the publication of clinically important articles in primary healthcare journals?

BACKGROUND: We conducted this analysis to determine i) which journals publish high-quality, clinically relevant studies in internal medicine, general/family practice, general practice nursing, and mental health; and ii) the proportion of clinically relevant articles in each journal. METHODS: We performed an analytic survey of a hand search of 170 general medicine, general healthcare, and specialty journals for 2000. Research staff assessed individual articles by using explicit criteria for scientific merit for healthcare application. Practitioners assessed the clinical importance of these articles. Outcome measures were the number of high-quality, clinically relevant studies published in the 170 journal titles and how many of these were published in each of four discipline-specific, secondary "evidence-based" journals (ACP Journal Club for internal medicine and its subspecialties; Evidence-Based Medicine for general/family practice; Evidence-Based Nursing for general practice nursing; and Evidence-Based Mental Health for all aspects of mental health). Original studies and review articles were classified for purpose: therapy and prevention, screening and diagnosis, prognosis, etiology and harm, economics and cost, clinical prediction guides, and qualitative studies. RESULTS: We evaluated 60,352 articles from 170 journal titles. The pass criteria of high-quality methods and clinically relevant material were met by 3059 original articles and 1073 review articles. For ACP Journal Club (internal medicine), four titles supplied 56.5% of the articles and 27 titles supplied the other 43.5%. For Evidence-Based Medicine (general/family practice), five titles supplied 50.7% of the articles and 40 titles supplied the remaining 49.3%. For Evidence-Based Nursing (general practice nursing), seven titles supplied 51.0% of the articles and 34 additional titles supplied 49.0%. For Evidence-Based Mental Health (mental health), nine titles supplied 53.2% of the articles and 34 additional titles supplied 46.8%. For the disciplines of internal medicine, general/family practice, and mental health (but not general practice nursing), the number of clinically important articles was correlated withScience Citation Index (SCI) Impact Factors. CONCLUSIONS: Although many clinical journals publish high-quality, clinically relevant and important original studies and systematic reviews, the articles for each discipline studied were concentrated in a small subset of journals. This subset varied according to healthcare discipline; however, many of the important articles for all disciplines in this study were published in broad-based healthcare journals rather than subspecialty or discipline-specific journals

Rituximab in B-Cell Hematologic Malignancies: A Review of 20 Years of Clinical Experience

Rituximab is a human/murine, chimeric anti-CD20 monoclonal antibody with established efficacy, and a favorable and well-defined safety profile in patients with various CD20-expressing lymphoid malignancies, including indolent and aggressive forms of B-cell non-Hodgkin lymphoma. Since its first approval 20 years ago, intravenously administered rituximab has revolutionized the treatment of B-cell malignancies and has become a standard component of care for follicular lymphoma, diffuse large B-cell lymphoma, chronic lymphocytic leukemia, and mantle cell lymphoma. For all of these diseases, clinical trials have demonstrated that rituximab not only prolongs the time to disease progression but also extends overall survival. Efficacy benefits have also been shown in patients with marginal zone lymphoma and in more aggressive diseases such as Burkitt lymphoma. Although the proven clinical efficacy and success of rituximab has led to the development of other anti-CD20 monoclonal antibodies in recent years (e.g., obinutuzumab, ofatumumab, veltuzumab, and ocrelizumab), rituximab is likely to maintain a position within the therapeutic armamentarium because it is well established with a long history of successful clinical use. Furthermore, a subcutaneous formulation of the drug has been approved both in the EU and in the USA for the treatment of B-cell malignancies. Using the wealth of data published on rituximab during the last two decades, we review the preclinical development of rituximab and the clinical experience gained in the treatment of hematologic B-cell malignancies, with a focus on the well-established intravenous route of administration. This article is a companion paper to A. Davies, et al., which is also published in this issue

Anticipatory and post hoc cushioning strategies: Optimism and defensive pessimism in “risky” situations

The concept of cognitive strategies is proposed as a model for the process by which individuals cushion themselves against threats to self-esteem in “risky” situations. Two strategies are discussed. The first is defensive pessimism, an anticipatory strategy that involves setting defensively low expectations prior to entering a situation, so as to defend against loss of self-esteem in the event of failure. The second is an optimistic strategy, where expectations are high at the outset, and post hoc restructuring of the situation is done when the outcome is known. Expectations about performance on an anagram task were collected from prescreened optimistics and defensive pessimists. After completion of the task, subjects were given false failure or success feedback. A posttest measuring self-reported satisfaction, feelings of control, and performance evaluations was administered. As predicted, subjects selected for defensive pessimist attitudes expected to perform significantly worse than did those selected for optimistic attitudes, even though there was no difference in actual performance. Moreover, optimists demonstrated attributional egotism in claiming significantly more control over their performance in the success condition than in the failure condition. Pessimists did not show this pattern. The data provide evidence of post hoc cushioning efforts among optimists, whereas defensive pessimists seem to be cushioned by their initial structuring of the situation. It is argued that these strategies can be understood as motivated attempts to solve the “problem” of a “risky” situation.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/44330/1/10608_2005_Article_BF01173471.pd

Organizational readiness to change assessment (ORCA): Development of an instrument based on the Promoting Action on Research in Health Services (PARIHS) framework

<p>Abstract</p> <p>Background</p> <p>The Promoting Action on Research Implementation in Health Services, or PARIHS, framework is a theoretical framework widely promoted as a guide to implement evidence-based clinical practices. However, it has as yet no pool of validated measurement instruments that operationalize the constructs defined in the framework. The present article introduces an Organizational Readiness to Change Assessment instrument (ORCA), organized according to the core elements and sub-elements of the PARIHS framework, and reports on initial validation.</p> <p>Methods</p> <p>We conducted scale reliability and factor analyses on cross-sectional, secondary data from three quality improvement projects (n = 80) conducted in the Veterans Health Administration. In each project, identical 77-item ORCA instruments were administered to one or more staff from each facility involved in quality improvement projects. Items were organized into 19 subscales and three primary scales corresponding to the core elements of the PARIHS framework: (1) Strength and extent of evidence for the clinical practice changes represented by the QI program, assessed with four subscales, (2) Quality of the organizational context for the QI program, assessed with six subscales, and (3) Capacity for internal facilitation of the QI program, assessed with nine subscales.</p> <p>Results</p> <p>Cronbach's alpha for scale reliability were 0.74, 0.85 and 0.95 for the evidence, context and facilitation scales, respectively. The evidence scale and its three constituent subscales failed to meet the conventional threshold of 0.80 for reliability, and three individual items were eliminated from evidence subscales following reliability testing. In exploratory factor analysis, three factors were retained. Seven of the nine facilitation subscales loaded onto the first factor; five of the six context subscales loaded onto the second factor; and the three evidence subscales loaded on the third factor. Two subscales failed to load significantly on any factor. One measured resources in general (from the context scale), and one clinical champion role (from the facilitation scale).</p> <p>Conclusion</p> <p>We find general support for the reliability and factor structure of the ORCA. However, there was poor reliability among measures of evidence, and factor analysis results for measures of general resources and clinical champion role did not conform to the PARIHS framework. Additional validation is needed, including criterion validation.</p

Introduction

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/67161/2/10.1177_0308275X9301300401.pd