3,445 research outputs found

    Radiocarbon Date List XI: Radiocarbon Dates from Marine Sediment Cores of the Iceland, Greenland, and Northeast Canadian Arctic Shelves and Nares Strait

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    Radiocarbon Date List XI contains an annotated listing of 178 AMS radiocarbon dates on samples from marine (169 samples) and lake (9 samples) sediment cores. Marine sediment cores, from which the samples for dating were taken, were collected on the Greenland Shelf, Baffin Bay, and the Eastern Canadian Arctic shelf. About 80% of the marine samples for dating were collected on the SW to N Icelandic shelf. The lake sediment cores were collected in northwestern Iceland. For dating of the marine samples, we submitted molluscs (117 samples), benthic and planktic foraminifera (45 samples), plant macrofauna (3 samples), and one serpulid worm. For dating of the lake cores, we submitted wood (8 samples) and one peat sample. The Conventional Radiocarbon Ages range from 294±9114C yr BP to 34,600±640 14C yr BP. The dates have been used to address a variety of research questions. The dates constrain the timing of high northern latitude late Quaternary environmental fluctuations, which include glacier extent, sea level history, isostatic rebound, sediment input, and ocean circulation. The dates also allowed assessment of the accuracy of commonly used reservoir correction. The samples were submitted by INSTAAR and affiliated researchers

    Grazing by captive Barnacle geese affects graminoid growth and productivity on Svalbard

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    Migratory geese breed in Svalbard in summer and return to Western Europe for the winter, feeding on wetlands and agricultural fields. Recent changes in climate, land use and the implementation of protective measures dramatically improved the birds\u27 ability to survive the winter, increasing population sizes and thus the potential grazing impact on Svalbard. This study measured live leaf length and aboveground productivity of Alopecurus borealis and Dupontia fisheri, widespread forage grasses on Svalbard, in order to make a quantitative assessment of the short term effects of different intensities of goose grazing. In addition we wanted to establish whether warming could enhance graminoid growth and regenerative capacity of grazed grasses. We carried out a factorial experiment of grazing (control, normal and high grazing pressure) using captive wild barnacle geese and temperature manipulation using open top chambers (OTCs) in a mesic and wet habitat in Adventdalen, Svalbard (78°N , 16°E ), following the growth of individual tillers before grazing and up until 20 days after grazing. OTCs enhanced temperatures and growth rates for Alopecurus in the mesic habitat, but slightly decreased belowground temperatures and early season growth for Dupontia in the wet habitat. Grazing stimulated growth rates resulting in increased cumulative leaf length production. The strength of response was greater for Alopecurus than Dupontia. We suggest that nutrients released by goose faeces were taken up by Alopecurus thus enhancing their growth rates, but that the thick layer of mosses prevented the addition of faeces from benefitting Dupontia as much

    Prevalence and course of somatic symptoms in patients with stress-related exhaustion: does sex or age matter

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    BACKGROUND: Both mental and somatic symptoms are commonly reported in patients with stress-related problems. We have explored the prevalence of somatic symptoms in patients seeking medical care for stress-related mental health problems and followed the course of illnes alongside with that the patients receive multimodal treatment. METHOD: This study comprises data from 228 patients (69% women, mean age 43 years) who fulfilled the criteria for Exhaustion Disorder (ED). Somatic symptoms were assessed at baseline and after 3, 6, 12 and 18 months using the one-page questionnaire Primary Care Evaluation of Mental Disorders. Prevalence of different symptoms was compared between men and women and patients, over and below 40 years of age, and possible predictors of recovery were explored. RESULTS: Tiredness and low energy are the core symptom reported by the patients. Almost all (98%) reported at least one somatic symptom and 45% reported six symptoms or more, which was similar for men and women. Nausea, gas or indigestion are the most common symptoms (67%) followed by headaches (65%) and dizziness (57%). The number of symptoms reported was significantly related to the severity of mental health problems. The only difference between the sexes was that “chest pain” and “pain or problems during sexual intercourse” were more common among males. Patients over forty more often reported “pain in arms, legs or joints, knees, hips” and this was also the only symptom that did not significantly decline during treatment. Neither sex, age, symptom duration before seeking medical care, education or any other predictor tested was shown to predict recovery in patients reporting six symptoms or more. CONCLUSION: A heavy burden of somatic symptoms was generally seen in most patients with stress-related exhaustion. Somatic symptoms are equally common in males and females and in younger and older patients. The somatic symptoms seem to be mostly stress-related since all symptoms, except musculoskeletal pain, reduce with individualised treatment designed for stress-related mental problems. This study brings to attention the complicated burden of both somatic and mental symptoms in patients with stress-related exhaustion, raising several clinical implications of interest to discuss

    Pneumococcal polysaccharide abrogates conjugate-induced germinal center reaction and depletes antibody secreting cell pool, causing hyporesponsiveness.

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    To access publisher's full text version of this article, please click on the hyperlink in Additional Links field or click on the hyperlink at the top of the page marked Files. This article is open access.Plain pneumococcal polysaccharide (PPS) booster administered during second year of life has been shown to cause hyporesponsiveness. We assessed the effects of PPS booster on splenic memory B cell responses and persistence of PPS-specific long-lived plasma cells in the bone marrow (BM).Neonatal mice were primed subcutanously (s.c.) or intranasally (i.n.) with pneumococcal conjugate (Pnc1-TT) and the adjuvant LT-K63, and boosted with PPS+LT-K63 or saline 1, 2 or 3 times with 16 day intervals. Seven days after each booster, spleens were removed, germinal centers (GC), IgM(+), IgG(+) follicles and PPS-specific antibody secreting cells (AbSC) in spleen and BM enumerated.PPS booster s.c., but not i.n., compromised the Pnc1-TT-induced PPS-specific Abs by abrogating the Pnc1-TT-induced GC reaction and depleting PPS-specific AbSCs in spleen and limiting their homing to the BM. There was no difference in the frequency of PPS-specific AbSCs in spleen and BM between mice that received 1, 2 or 3 PPS boosters s.c.. Repeated PPS+LT-K63 booster i.n. reduced the frequency of PPS-specific IgG(+) AbSCs in BM.PPS booster-induced hyporesponsiveness is caused by abrogation of conjugate-induced GC reaction and depletion of PPS-specific IgG(+) AbSCs resulting in no homing of new PPS-specific long-lived plasma cells to the BM or survival. These results should be taken into account in design of vaccination schedules where polysaccharides are being considered.Icelandic Research Fund for Graduate Students/ 50940005, Icelandic Research Fund/40438021-23, Eimskip University Fund, University of Iceland Research Fund, Landspitali University Hospital Research Fun

    Mapping and Assessing Surface Morphology of Holocene Lava Field in Krafla (NE Iceland) Using Hyperspectral Remote Sensing

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    Iceland is well known for its volcanic activity due to its location on the spreading Mid Atlantic Ridge and one of the earth’s hot spot. In the past 1000 years there were about 200 eruptions occurring in Iceland, meaning volcanic eruptions occurred every four to five years, on average. Iceland currently has 30 active volcano systems, distributed evenly throughout the socalled Neovolcanic Zone. One of these volcanic systems is the Krafla central volcano, which is located in the northern Iceland at latitude 65°42'53'' N and longitude 16°43'40'' W. Krafla has produced two volcanic events in historic times: 1724-1729 (Myvatn Fires) and 1975-1984 (Krafla Fires). The Krafla Fires began in December 1975 and lasted until September 1984. This event covered about 36-km2 surrounding area with lava, having a total volume of 0.25-0.3 km3 . Previous studies of lava surface morphology at Krafla focused on an open channel area by remote sensing are essential as a complementary tool to the previous investigations and to extend the area of mapping. Using Spectral Angle Mapper (SAM) classification approach by selecting spectral reflectance end members, this study has successfully produced a detailed map of the surface morphology in Krafla lava field EO-1 Hyperion (Hyperspectral) satellite images. The overall accuracy of lava morphology map is 61.33% (EO-1 Hyperion). These results show that hyperspectral remote sensing is an acceptable alternative to field mapping and assessing the lava surface morphology in the Krafla lava field. In order to get validation of the satellite image’s spectral reflectance, in-situ measurements of the lava field’s spectral reflectance using ASD FieldSpec3 is essential.LPDP scholarship (Indonesia Endowment Fund for Education
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