98 research outputs found

    The diagnostic accuracy to Technetium 99m labelled erythrocyte scintigraphy in the investigation of hepatic mass lesions : special reference to hepatic cavernous haemangioma and hepatocellular carcinoma

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    The distinction between cavernous haemangiomas of the liver (which are the second most common hepatic mass lesions) from malignant lesions, is often difficult. An incorrect diagnosis of cavernous haemangioma, in a patient with malignancy, may adversely influence the outcome of subsequent treatment in these patients, due to delay in therapy. Although previous studies have suggested that âčâčᔐTc erythrocyte blood pool scintigraphy is both highly sensitive and specific for haemangiomas, a basic flaw in all previous studies has been the small number of control patients studied. Bayesian analysis clearly shows that specificity for a test is dependant on the pre-test probability of the lesion being present. Thus all the studies done to date, may reflect an inappropriately high specificity for âčâčᔐTc scintigraphy, in diagnosing cavernous haemangiomas, because they have mainly studied patients with haemangiomas and relatively few patients with other lesions. This study was thus undertaken to clarify the true accuracy of this technique, in distinguishing haemangiomas from other hepatic mass lesions, by studying a large number of patients with haemangiomas and other hepatic mass lesions

    A Rare Case of Jejunal Arterio-Venous Fistula: Treatment with Superselective Catheter Embolization with a Tracker-18 Catheter and Microcoils

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    Arterio-venous fistulas may develop spontaneously, following trauma or infection, or be iatrogenic in nature. We present a rare case of a jejunal arterio- venous fistula in a 35-year-old man with a history of pancreatic head resection that had been performed two years previously because of chronic pancreatitis. The patient was admitted with acute upper abdominal pain, vomiting and an abdominal machinery-type bruit. The diagnosis of a jejunal arterio-venous fistula was established by MR imaging. Transfemoral angiography was performed to assess the possibility of catheter embolization. The angiographic study revealed a small aneurysm of the third jejunal artery, abnormal early filling of dilated jejunal veins and marked filling of the slightly dilated portal vein (13-14 mm). We considered the presence of segmental portal hypertension. The patient was treated with coil embolization in the same angiographic session. This case report demonstrates the importance of auscultation of the abdomen in the initial clinical examination. MR imaging and color Doppler ultrasound are excellent noninvasive tools in establishing the diagnosis. The role of interventional radiological techniques in the treatment of early portal hypertension secondary to jejunal arterio-venous fistula is discussed at a time when this condition is still asymptomatic. A review of the current literature is include

    Correlation of gastrointestinal perforation location and amount of free air and ascites on CT imaging.

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    PURPOSE To analyze the amount of free abdominal gas and ascites on computed tomography (CT) images relative to the location of a perforation. METHODS We retrospectively included 172 consecutive patients (93:79 = m:f) with GIT perforation, who underwent abdominal surgery (ground truth for perforation location). The volume of free air and ascites were quantified on CT images by 4 radiologists and a semiautomated software. The relation of the perforation location (upper/lower GIT) and amount of free air and ascites was analyzed by the Mann-Whitney test. Furthermore, best volume cutoff for upper and lower GIT perforation, areas under the curve (AUC), and interreader volume agreement were assessed. RESULTS There was significantly more abdominal ascites with upper GIT perforation (333 ml, range 5 to 2000 ml) than with lower GIT perforation (100 ml, range 5 to 2000 ml, p = 0.022). The highest volume of free air was found with perforations of the stomach, descending colon and sigmoid colon. Significantly less free air was found with perforations of the small bowel and ascending colon compared to the aforementioned. An ascites volume > 333 ml was associated with an upper GIT perforation demonstrating an AUC of 0.63 ± 0.04. CONCLUSION Using a two-step process based on the volumes of free air and free fluid can help localizing the site of perforation to the upper, middle or lower GI tract

    Newfoundland Neogene sediment drifts: transition from the Paleogene greenhouse to the modern icehouse

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    This workshop brought together specialists from various fields to develop a drilling proposal to fill the "Oligo-Miocene Gap" that exists in our understanding of the functions of Earth's systems. We propose to establish the first continuous high-deposition record of the Oligo-Miocene through new International Ocean Discovery Program (IODP) drilling in the North Atlantic to allow the development of a continuous Neogene cyclostratigraphy and to enhance our knowledge of Oligo-Miocene ocean–ice–climate dynamics. The workshop was held in Heidelberg from 15 to 17 September 2014 funded by ESF (EARTHTIME EU), NSF, and the ECORD MagellanPlus Workshop Series Program. A total of 24 participants from six different countries (Australia, France, Germany, the Netherlands, United Kingdom, and United States) attended the workshop, including several early career stage researchers. We discussed certain aspects of Cenozoic paleoceanography and paleoclimate and how the gaps in the Oligo-Miocene could be filled using scientific drilling. The ultimate goal of the workshop (to submit a pre-proposal to IODP) was achieved (IODP Proposal 874-pre was submitted 1 October 2014). Our workshop consisted of overview presentations followed by self-selected breakout groups that discussed different topics and produced text and figures for the proposal. Here, we give a short overview of the major topics discussed during the workshop and the scientific goals presented in the resulting IODP pre-proposal

    An astronomically dated record of Earth's climate and its predictability over the last 66 million years.

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    Much of our understanding of Earth's past climate comes from the measurement of oxygen and carbon isotope variations in deep-sea benthic foraminifera. Yet, long intervals in existing records lack the temporal resolution and age control needed to thoroughly categorize climate states of the Cenozoic era and to study their dynamics. Here, we present a new, highly resolved, astronomically dated, continuous composite of benthic foraminifer isotope records developed in our laboratories. Four climate states-Hothouse, Warmhouse, Coolhouse, Icehouse-are identified on the basis of their distinctive response to astronomical forcing depending on greenhouse gas concentrations and polar ice sheet volume. Statistical analysis of the nonlinear behavior encoded in our record reveals the key role that polar ice volume plays in the predictability of Cenozoic climate dynamics

    Are avian predators effective biological control agents for rodent pest management in agricultural systems?

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    Worldwide rodent pests are of significant economic and health importance. Controlling rodent pests will, therefore, not only benefit food security but also human and animal health. While rodent pests are most often chemically controlled, there is increased interest in biological control through avian predation. A rich body of research has addressed the impact of avian predators on wild rodent populations, but little is known about the effectiveness of avian predators as biological control agents of rodent pests in agricultural systems. In this study, we systematically reviewed research that investigated different aspects of avian predation on rodent pest populations in order to increase our understanding of the impact and effectiveness of avian predation on rodent pests. Several avian predators (Tyto alba, Elanus axillaris Falco tinnunculus, F. cenchroides, Bubo bengalensis, Buteo rufinus) were commonly cited in the biological control of rodents; however, barn owls (T. alba) are the most cited species (86% of studies). We found some support that the use of avian predators produced positive, measurable effects where increased presence of avian predators tended to lower rodent pest numbers, resulting in lower crop damage. However, our review highlighted several shortcomings related to research on avian predation of rodent pests. First, research concerning rodent pest control through avian predation was limited (1.86 articles per year). Secondly, we found that studies lack statistical rigor to detect and measure change in rodent pest species abundance. Finally, the majority of studies were short term and therefore not able to evaluate long term sustainable rodent pest population suppression. We suggest that current shortcomings could be adequately addressed with control-treatment studies that quantitatively investigate the effects of avian predation on rodent pest populations and agricultural impact. Such research could help develop recommendations regarding the use of avian predators in rodent pest management

    A systematic review of rodent pest research in Afro-Malagasy small-holder farming systems : are we asking the right questions

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    Rodent pests are especially problematic in terms of agriculture and public health since they can inflict considerable economic damage associated with their abundance, diversity, generalist feeding habits and high reproductive rates. To quantify rodent pest impacts and identify trends in rodent pest research impacting on small-holder agriculture in the Afro- Malagasy region we did a systematic review of research outputs from 1910 to 2015, by developing an a priori defined set of criteria to allow for replication of the review process. We followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. We reviewed 162 publications, and while rodent pest research was spatially distributed across Africa (32 countries, including Madagascar), there was a disparity in number of studies per country with research biased towards four countries (Tanzania [25%], Nigeria [9%], Ethiopia [9%], Kenya [8%]) accounting for 51% of all rodent pest research in the Afro- Malagasy region. There was a disparity in the research themes addressed by Tanzanian publications compared to publications from the rest of the Afro-Malagasy region where research in Tanzania had a much more applied focus (50%) compared to a more basic research approach (92%) in the rest of the Afro-Malagasy region. We found that pest rodents have a significant negative effect on the Afro-Malagasy small-holder farming communities. Crop losses varied between cropping stages, storage and crops and the highest losses occurred during early cropping stages (46% median loss during seedling stage) and the mature stage (15% median loss). There was a scarcity of studies investigating the effectiveness of various management actions on rodent pest damage and population abundance. Our analysis highlights that there are inadequate empirical studies focused on developing sustainable control methods for rodent pests and rodent pests in the Africa-Malagasy context is generally ignored as a research topic.S1 Table. PRISMA checklist.S2 Table. List of rodent genera detected in rodent pest research in African agricultural systems from 1960±2015.S3 Table. List of different crops and cropping system as impacted by rodent pests in African agriculture (1960±2015).S1 List. Complete list of all publications used in the review±Publications in bold did not have full texts available at time of review.S2 List. Web of Science TM search history±.S1 Web of ScienceTM saved search.A European Union 9th European Development Fund grant from the African Caribbean and Pacific Science and Technology Programme (FED/2013/330-223), a grant from the United Kingdom's Department for International Development (AgriTT/894), a grant from the Sasol Agriculture Trust (South Africa), and International Foundation for Science (SE)-D/4984-2 to LHS.http://www.plosone.orgam2017Animal and Wildlife Science

    Cyclostratigraphy and eccentricity tuning of the early Oligocene through early Miocene (30.1–17.1 Ma): Cibicides mundulus stable oxygen and carbon isotope records from Walvis Ridge Site 1264

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    Few astronomically calibrated high-resolution (≀5 kyr) climate records exist that span the Oligocene–Miocene time interval. Notably, available proxy records show responses varying in amplitude at frequencies related to astronomical forcing, and the main pacemakers of global change on astronomical time-scales remain debated. Here we present newly generated X-ray fluorescence core scanning and benthic foraminiferal stable oxygen and carbon isotope records from Ocean Drilling Program Site 1264 (Walvis Ridge, southeastern Atlantic Ocean). Complemented by data from nearby Site 1265, the Site 1264 benthic stable isotope records span a continuous ∌13-Myr interval of the Oligo-Miocene (30.1–17.1 Ma) at high resolution (∌3.0 kyr). Spectral analyses in the stratigraphic depth domain indicate that the largest amplitude variability of all proxy records is associated with periods of ∌3.4 m and ∌0.9 m, which correspond to 405- and ∌110-kyr eccentricity, using a magnetobiostratigraphic age model. Maxima in CaCO3 content, ÎŽ18O and ÎŽ13C are interpreted to coincide with ∌110 kyr eccentricity minima. The strong expression of these cycles in combination with the weakness of the precession- and obliquity-related signals allow construction of an astronomical age model that is solely based on tuning the CaCO3 content to the nominal (La2011_ecc3L) eccentricity solution. Very long-period eccentricity maxima (∌2.4-Myr) are marked by recurrent episodes of high-amplitude ∌110-kyr ÎŽ18O cycles at Walvis Ridge, indicating greater sensitivity of the climate/cryosphere system to short eccentricity modulation of climatic precession. In contrast, the responses of the global (high-latitude) climate system, cryosphere, and carbon cycle to the 405-kyr cycle, as expressed in benthic ÎŽ18O and especially ÎŽ13C signals, are more pronounced during ∌2.4-Myr minima. The relationship between the recurrent episodes of high-amplitude ∌110-kyr ÎŽ18O cycles and the ∌1.2-Myr amplitude modulation of obliquity is not consistent through the Oligo-Miocene. Identification of these recurrent episodes at Walvis Ridge, and their pacing by the ∌2.4-Myr eccentricity cycle, revises the current understanding of the main climate events of the Oligo-Miocene

    A systematic review of rodent pest research in Afro-Malagasy small-holder farming systems: Are we asking the right questions?

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    Rodent pests are especially problematic in terms of agriculture and public health since they can inflict considerable economic damage associated with their abundance, diversity, generalist feeding habits and high reproductive rates. To quantify rodent pest impacts and identify trends in rodent pest research impacting on small-holder agriculture in the Afro-Malagasy region we did a systematic review of research outputs from 1910 to 2015, by developing an a priori defined set of criteria to allow for replication of the review process. We followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. We reviewed 162 publications, and while rodent pest research was spatially distributed across Africa (32 countries, including Madagascar), there was a disparity in number of studies per country with research biased towards four countries (Tanzania [25%], Nigeria [9%], Ethiopia [9%], Kenya [8%]) accounting for 51% of all rodent pest research in the Afro-Malagasy region. There was a disparity in the research themes addressed by Tanzanian publications compared to publications from the rest of the Afro-Malagasy region where research in Tanzania had a much more applied focus (50%) compared to a more basic research approach (92%) in the rest of the Afro-Malagasy region. We found that pest rodents have a significant negative effect on the Afro-Malagasy small-holder farming communities. Crop losses varied between cropping stages, storage and crops and the highest losses occurred during early cropping stages (46% median loss during seedling stage) and the mature stage (15% median loss). There was a scarcity of studies investigating the effectiveness of various management actions on rodent pest damage and population abundance. Our analysis highlights that there are inadequate empirical studies focused on developing sustainable control methods for rodent pests and rodent pests in the Africa-Malagasy context is generally ignored as a research topic
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