806 research outputs found

    Sea-air CO2 fluxes in the Indian Ocean between 1990 and 2009

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    The Indian Ocean (44 S-30 N) plays an important role in the global carbon cycle, yet it remains one of the most poorly sampled ocean regions. Several approaches have been used to estimate net sea-air CO2 fluxes in this region: interpolated observations, ocean biogeochemical models, atmospheric and ocean inversions. As part of the RECCAP (REgional Carbon Cycle Assessment and Processes) project, we combine these different approaches to quantify and assess the magnitude and variability in Indian Ocean sea-air CO2 fluxes between 1990 and 2009. Using all of the models and inversions, the median annual mean sea-air CO2 uptake of −0.37 ± 0.06 PgC yr -1 is consistent with the −0.24 ± 0.12 PgC yr -1 calculated from observations. The fluxes from the southern Indian Ocean (18-44 S; -0.43 ± 0.07 PgC yr-1 are similar in magnitude to the annual uptake for the entire Indian Ocean. All models capture the observed pattern of fluxes in the Indian Ocean with the following exceptions: underestimation of upwelling fluxes in the northwestern region (off Oman and Somalia), overestimation in the northeastern region (Bay of Bengal) and underestimation of the CO2 sink in the subtropical convergence zone. These differences were mainly driven by lack of atmospheric CO2 data in atmospheric inversions, and poor simulation of monsoonal currents and freshwater discharge in ocean biogeochemical models. Overall, the models and inversions do capture the phase of the observed seasonality for the entire Indian Ocean but overestimate the magnitude. The predicted sea-air CO 2 fluxes by ocean biogeochemical models (OBGMs) respond to seasonal variability with strong phase lags with reference to climatological CO 2 flux, whereas the atmospheric inversions predicted an order of magnitude higher seasonal flux than OBGMs. The simulated interannual variability by the OBGMs is weaker than that found by atmospheric inversions. Prediction of such weak interannual variability in CO2 fluxes by atmospheric inversions was mainly caused by a lack of atmospheric data in the Indian Ocean. The OBGM models suggest a small strengthening of the sink over the period 1990-2009 of -0.01 PgC decade-1. This is inconsistent with the observations in the southwestern Indian Ocean that shows the growth rate of oceanic pCO 2 was faster than the observed atmospheric CO2 growth, a finding attributed to the trend of the Southern Annular Mode (SAM) during the 1990s

    PPI-Delayed Diagnosis of Gastrinoma: Oncologic Victim of Pharmacologic Success

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    Functional neuroendocrine tumors are often low-grade malignant neoplasms that can be cured by surgery if detected early, and such detection may in turn be accelerated by the recognition of neuropeptide hypersecretion syndromes. Uniquely, however, relief of peptic symptoms induced by hypergastrinemia is now available from acid-suppressive drugs such as proton-pump inhibitors (PPIs). Here we describe a clinical case in which time to diagnosis from the onset of peptic symptoms was delayed more than 10 years, in part reflecting symptom masking by continuous prescription of the PPI omeprazole. We propose diagnostic criteria for this under-recognized new clinical syndrome, and recommend that physicians routinely measure serum gastrin levels in persistent cases of PPI-dependent dyspepsia unassociated with H. pylori

    Mapping social work across 10 countries: Structure, intervention, identity and challenges

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    An emerging global consciousness and rising attention given to international social work development has seen the recognition of comparative research within the profession. Understanding the functioning and organisation of social work within various country contexts is critical in order to formulate knowledge around its overall impact, successes and challenges, allowing social workers to learn from one another and build professional consolidation. The profession is mapped out in 10 countries, reflecting on its structure, identity and development. Although the profession is developing globally, it is also experiencing significant challenges. Key insights, conclusions and recommendations for future research are presented

    Phase I dose escalation and pharmacokinetic study of pluronic polymer-bound doxorubicin (SP1049C) in patients with advanced cancer

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    SP1049C is a novel anticancer agent containing doxorubicin and two nonionic pluronic block copolymers. In preclinical studies, SP1049C demonstrated increased efficacy compared to doxorubicin. The objectives of this first phase I study were to determine the toxicity profile, dose-limiting toxicity, maximum tolerated dose and pharmacokinetic profile of SP1049C, and to document any antitumour activity. The starting dose was 5 mg m−2 (doxorubicin content) as an intravenous infusion once every 3 weeks for up to six cycles. A total of 26 patients received 78 courses at seven dose levels. The dose-limiting toxicity was myelosuppression and DLT was reached at 90 mg m−2. The maximum tolerated dose was 70 mg m−2 and is recommended for future trials. The pharmacokinetic profile of SP1049C showed a slower clearance than has been reported for conventional doxorubicin. Evidence of antitumour activity was seen in some patients with advanced resistant solid tumours. Phase II trials with this agent are now warranted to further define its antitumour activity and safety profile

    Morphology-Controllable Synthesis of CeO2on a Pt Electrode

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    Nanoscale cerium dioxides with shape of nanoparticles, nanorods, and nanotubes were electrochemically synthesized. The morphology of CeO2was modulated by changing electrode potential and potential direction. CeO2nanorods and CeO2nanotubes were synthesized via the potentiostatic and cyclic voltammeteric methods, respectively. The morphology and structure of the obtained CeO2were characterized by field emission scanning electron microscope (FESEM) and X-ray diffraction (XRD). A possible formation mechanism has been suggested to illuminate the relationship between the preparation condition and the morphology of CeO2

    IPP-rich milk protein hydrolysate lowers blood pressure in subjects with stage 1 hypertension, a randomized controlled trial

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    <p>Abstract</p> <p>Background</p> <p>Milk derived peptides have been identified as potential antihypertensive agents. The primary objective was to investigate the effectiveness of IPP-rich milk protein hydrolysates (MPH) on reducing blood pressure (BP) as well as to investigate safety parameters and tolerability. The secondary objective was to confirm or falsify ACE inhibition as the mechanism underlying BP reductions by measuring plasma renin activity and angiotensin I and II.</p> <p>Methods</p> <p>We conducted a randomized, placebo-controlled, double blind, crossover study including 70 Caucasian subjects with prehypertension or stage 1 hypertension. Study treatments consisted of daily consumption of two capsules MPH1 (each containing 7.5 mg Isoleucine-Proline-Proline; IPP), MPH2 (each containing 6.6 mg Methionine-Alanine-Proline, 2.3 mg Leucine-Proline-Proline, 1.8 mg IPP), or placebo (containing cellulose) for 4 weeks.</p> <p>Results</p> <p>In subjects with stage 1 hypertension, MPH1 lowered systolic BP by 3.8 mm Hg (P = 0.0080) and diastolic BP by 2.3 mm Hg (P = 0.0065) compared with placebo. In prehypertensive subjects, the differences in BP between MPH1 and placebo were not significant. MPH2 did not change BP significantly compared with placebo in stage I hypertensive or prehypertensive subjects. Intake of MPHs was well tolerated and safe. No treatment differences in hematology, clinical laboratory parameters or adverse effects were observed. No significant differences between MPHs and placebo were found in plasma renin activity, or angiotensin I and II.</p> <p>Conclusions</p> <p>MPH1, containing IPP and no minerals, exerts clinically relevant BP lowering effects in subjects with stage 1 hypertension. It may be included in lifestyle changes aiming to prevent or reduce high BP.</p> <p>Trial registration</p> <p>ClinicalTrials.gov NCT00471263</p

    A social network analysis of social cohesion in a constructed pride: Implications for ex situ reintroduction of the African Lion (Panthera leo)

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    Animal conservation practices include the grouping of captive related and unrelated individuals to form a social structure which is characteristic of that species in the wild. In response to the rapid decline of wild African lion (Panthera leo) populations, an array of conservational strategies have been adopted. Ex situ reintroduction of the African lion requires the construction of socially cohesive pride structures prior to wild release. This pilot study adopted a social network theory approach to quantitatively assess a captive pride's social structure and the relationships between individuals within them. Group composition (who is present in a group) and social interaction data (social licking, greeting, play) was observed and recorded to assess social cohesion within a released semi-wild pride. UCINET and SOCPROG software was utilised to represent and analyse these social networks. Results indicate that the pride is socially cohesive, does not exhibit random associations, and the role of socially influential keystone individuals is important for maintaining social bondedness within a lion pride. These results are potentially informative for the structure of lion prides, in captivity and in the wild, and could have implications for captive and wild-founder reintroductions

    Isolation of microplastics in biota-rich seawater samples and marine organisms.

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    notes: PMCID: PMC3970126types: Journal Article; Research Support, Non-U.S. Gov'tThis is an open access article that is freely available in ORE or from the publisher's web site. Please cite the published version.Microplastic litter is a pervasive pollutant present in aquatic systems across the globe. A range of marine organisms have the capacity to ingest microplastics, resulting in adverse health effects. Developing methods to accurately quantify microplastics in productive marine waters, and those internalized by marine organisms, is of growing importance. Here we investigate the efficacy of using acid, alkaline and enzymatic digestion techniques in mineralizing biological material from marine surface trawls to reveal any microplastics present. Our optimized enzymatic protocol can digest >97% (by weight) of the material present in plankton-rich seawater samples without destroying any microplastic debris present. In applying the method to replicate marine samples from the western English Channel, we identified 0.27 microplastics m(-3). The protocol was further used to extract microplastics ingested by marine zooplankton under laboratory conditions. Our findings illustrate that enzymatic digestion can aid the detection of microplastic debris within seawater samples and marine biota.Natural Environment Research Council (NERC
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