22 research outputs found

    Killer whales and marine mammal trends in the North Pacific : a re-examination of evidence for sequential megafauna collapse and the prey-switching hypothesis

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    This paper is not subject to U.S. copyright. The definitive version was published in Marine Mammal Science 23 (2007): 766–802, doi:10.1111/j.1748-7692.2006.00093.x.Springer et al. (2003) contend that sequential declines occurred in North Pacific populations of harbor and fur seals, Steller sea lions, and sea otters. They hypothesize that these were due to increased predation by killer whales, when industrial whaling's removal of large whales as a supposed primary food source precipitated a prey switch. Using a regional approach, we reexamined whale catch data, killer whale predation observations, and the current biomass and trends of potential prey, and found little support for the prey-switching hypothesis. Large whale biomass in the Bering Sea did not decline as much as suggested by Springer et al., and much of the reduction occurred 50–100 yr ago, well before the declines of pinnipeds and sea otters began; thus, the need to switch prey starting in the 1970s is doubtful. With the sole exception that the sea otter decline followed the decline of pinnipeds, the reported declines were not in fact sequential. Given this, it is unlikely that a sequential megafaunal collapse from whales to sea otters occurred. The spatial and temporal patterns of pinniped and sea otter population trends are more complex than Springer et al. suggest, and are often inconsistent with their hypothesis. Populations remained stable or increased in many areas, despite extensive historical whaling and high killer whale abundance. Furthermore, observed killer whale predation has largely involved pinnipeds and small cetaceans; there is little evidence that large whales were ever a major prey item in high latitudes. Small cetaceans (ignored by Springer et al.) were likely abundant throughout the period. Overall, we suggest that the Springer et al. hypothesis represents a misleading and simplistic view of events and trophic relationships within this complex marine ecosystem

    Osteoporotic vertebral compression fractures augmentation by injectable partly resorbable ceramic bone substitute (Ceramentℱ|SPINE SUPPORT): a prospective nonrandomized study.

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    INTRODUCTION: The aim of this study is to evaluate the long-term stabilizing-healing effectiveness and influence on adjacent intact vertebral bodies of a new injectable partly resorbable calcium sulfate (60 wt.%)/hydroxyapatite (40 wt.%) bone substitute employed in vertebral augmentation of osteoporotic collapses. METHODS: From April 2009 to April 2011, 80 patients underwent vertebral augmentation. Patients enrolling criteria were age >20 years and symptomatic osteoporotic vertebral collapse from low-energy trauma encompassed between levels T5 to L5. Preoperative and postoperative imaging studies consisted of computed tomography, plain X-ray, dual X-ray absorptiometry scanning, and magnetic resonance. Pain intensity has been evaluated by an 11-point visual analog scale (VAS) and physical and quality of life compromise assessments have been evaluated by Oswestry Disability Questionnaire (ODI). All procedures have been performed fluoroscopically guided by left unilateral approach under local anesthesia and mild sedation. RESULTS: VAS-based pain trend over the 12-month follow-up has shown a statistically significant (p < 0.001) decrease, starting from 7.68 (SD 1.83) preoperatively with an immediate first day decrease at 3.51 (SD 2.16) and 0.96 (SD 0.93) at 12 months. ODI score dropped significantly from 54.78% to 20.12% at 6 months. No device-related complication has been reported. In no case a new incidental adjacent fracture has been reported. CONCLUSION: Data show how this injectable partly resorbable ceramic cement could be a nontoxic and lower stiffness alternative to polymethylmethacrylate for immediate and long-term stabilization of osteoporotic collapsed vertebral bodies

    Osteoporotic vertebral compression fracture augmentation by injectable partly resorbable ceramic bone substitute (Ceramentℱ|SPINESUPPORT): a prospective nonrandomized study

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    INTRODUCTION: This study aimed to evaluate long-term stabilizing healing effectiveness and influence on adjacent intact vertebral bodies of a new injectable partly resorbable calcium sulfate (60 wt.%)/hydroxyapatite (40 wt.%) bone substitute employed in vertebral augmentation of osteoporotic collapses. METHODS: From April 2009 to April 2011, 80 patients underwent vertebral augmentation. Patient enrolment criteria are as follows: age more than 20 years; symptomatic osteoporotic vertebral compression fracture from low energy trauma encompassing level T5 to L1 and classified as A1.1 to A1.2 according to the AO classification system; vertebral height compression within 0-75% compared to the posterior (dorsal) wall; client history confirming the age of the compression fracture to be within at least 4 weeks; and patients who are able to understand the procedure and participate in the study. Preoperative and postoperative imaging studies consisted of computed tomography, plain X-ray, dual X-ray absorptiometry scanning, and magnetic resonance. Pain intensity has been evaluated by an 11-point visual analog scale (VAS), and physical and quality of life compromise assessments have been evaluated by Oswestry Disability Questionnaire (ODI). All procedures have been performed fluoroscopically guided by left unilateral approach under local anesthesia and mild sedation. RESULTS: VAS-based pain trend over 12-month follow-up has shown a statistical significant (p < 0.001) decrease, starting from 7.68 (SD 1.83) preoperatively with an immediate first day decrease at 3.51 (SD 2.16) and 0.96 (SD 0.93) at 12 months. The ODI score dropped significantly from 54.78% to 20.12% at 6 months. None device-related complication has been reported. In no case, a new incidental adjacent fracture has been reported. CONCLUSION: Data show how this injectable partly resorbable ceramic cement could be a nontoxic and lower stiffness alternative to polymethylmethacrylate for immediate and long-term stabilization of osteoporotic collapsed vertebral bodies

    Percutaneous vertebroplasty: Multi-centric results from EVEREST experience in large cohort of patients.

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    PURPOSE: The purpose of this study was to prospectively evaluate results and complications of percutaneous vertebroplasty (PV) performed in 6 different Italian Centres belonging to the European VErtebroplasty RESearch Team (E.VE.RES.T) in a large series of patients. MATERIALS AND METHODS: Follow-up was obtained in 4547 patients (3211 females and 1336 males; mean age 70.2years) that underwent PV for a total of 13.437 treated vertebrae. Procedures were performed by using fluoroscopic guidance or combined CT-fluoroscopic guidance. All patients underwent PV in local anaesthesia except for second cervical vertebrae treated with a trans-oral approach that required general anaesthesia. RESULTS: 4004 out of 4547 (88.0%) patients reported significant pain relief (difference>or=2 point in pain evaluated with an 11-point visual analogue scale; p<0.0001) within 48h: an average of 7.7±0.4 dropped to 1.8±0.6 in the osteoporotic patients; 8.3±0.4 to 2.4±0.4 in metastases; 8.3±0.4 to 1.7±1.0 in myeloma; 6.2±3.5 to 0.3±0.2 in angioma and 7.4±0.4 to 1.4±0.9 in trauma. 430 osteoporotic patients (13%) were retreated for a subsequent fracture; in 302/430 patients (70.2%), the new fracture occurred in the contiguous vertebra. No major neurologic complications were reported and the most frequent minor complication was venous leakage (20.5%). CONCLUSIONS: This large series of patients confirms that percutaneous vertebroplasty is an effective and safe procedure in the treatment of vertebral fractures. Best results are obtained in the treatment of myeloma and trauma

    Draft U.S. Pacific Marine Mammal Stock Assessments: 2009

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    Under the 1994 amendments to the Marine Mammal Protection Act (MMPA), the National Marine Fisheries Service (NMFS) and the U.S. Fish and Wildlife Service (USFWS) are required to publish Stock Assessment Reports for all stocks of marine mammals within U.S. waters, to review new information every year for strategic stocks and every three years for non-strategic stocks, and to update the stock assessment reports when significant new information becomes available. This report presents stock assessments for 13 Pacific marine mammal stocks under NMFS jurisdiction, including 8 “strategic” stocks and 5 “non-strategic” stocks (see summary table). A new stock assessment for humpback whales in American Samoa waters is included in the Pacific reports for the first time. New or revised abundance estimates are available for 9 stocks, including Eastern North Pacific blue whales, American Samoa humpback whales, five U.S. west coast harbor porpoise stocks, the Hawaiian monk seal, and southern resident killer whales. A change in the abundance estimate of Eastern North Pacific blue whales reflects a recommendation from the Pacific Scientific Review Group to utilize mark-recapture estimates for this population, which provide a better estimate of total population size than the average of recent line-transect and mark-recapture estimates. The ‘Northern Oregon/Washington Coast Stock’ harbor porpoise stock assessment includes a name change (‘Oregon’ is appended to ‘Northern Oregon’) to reflect recent stock boundary changes. Changes in abundance estimates for the two stocks of harbor porpoise that occur in Oregon waters are the result of these boundary changes, and do not reflect biological changes in the populations. Updated information on the three stocks of false killer whales in Hawaiian waters is also included in these reports. Information on the remaining 50 Pacific region stocks will be reprinted without revision in the final 2009 reports and currently appears in the 2008 reports (Carretta et al. 2009). Stock Assessments for Alaskan marine mammals are published by the National Marine Mammal Laboratory (NMML) in a separate report. Pacific region stock assessments include those studied by the Southwest Fisheries Science Center (SWFSC, La Jolla, California), the Pacific Islands Fisheries Science Center (PIFSC, Honolulu, Hawaii), the National Marine Mammal Laboratory (NMML, Seattle, Washington), and the Northwest Fisheries Science Center (NWFSC, Seattle, WA). Northwest Fisheries Science Center staff prepared the report on the Eastern North Pacific Southern Resident killer whale. National Marine Mammal Laboratory staff prepared the Northern Oregon/Washington coast harbor porpoise stock assessment. Pacific Islands Fisheries Science Center staff prepared the report on the Hawaiian monk seal. Southwest Fisheries Science Center staff prepared stock assessments for 9 stocks. The stock assessment for the American Samoa humpback whale was prepared by staff from the Center for Coastal Studies, Hawaiian Islands Humpback National Marine Sanctuary, the Smithsonian Institution, and the Southwest Fisheries Science Center. Draft versions of the stock assessment reports were reviewed by the Pacific Scientific Review Group at the November 2008, Maui meeting. The authors also wish to thank those who provided unpublished data, especially Robin Baird and Joseph Mobley, who provided valuable information on Hawaiian cetaceans. Any omissions or errors are the sole responsibility of the authors. This is a working document and individual stock assessment reports will be updated as new information on marine mammal stocks and fisheries becomes available. Background information and guidelines for preparing stock assessment reports are reviewed in Wade and Angliss (1997). The authors solicit any new information or comments which would improve future stock assessment reports. These Stock Assessment Reports summarize information from a wide range of sources and an extensive bibliography of all sources is given in each report. We strongly urge users of this document to refer to and cite original literature sources rather than citing this report or previous Stock Assessment Reports. If the original sources are not accessible, the citation should follow the format: [Original source], as cited in [this Stock Assessment Report citation]
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