14 research outputs found

    Effects of agricultural land use on fluvial carbon dioxide, methane and nitrous oxide concentrations in a large European river, the Meuse (Belgium)

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    peer reviewedWe report a data-set of CO2, CH4, and N2O concentrations in the surface waters of the Meuse river network in Belgium, obtained during four surveys covering 50 stations (summer 2013 and late winter 2013, 2014 and 2015), from yearly cycles in four rivers of variable size and catchment land cover, and from 111 groundwater samples. Surface waters of the Meuse river network were over-saturated in CO2, CH4, N2O with respect to atmospheric equilibrium, acting as sources of these greenhouse gases to the atmosphere, although the dissolved gases also showed marked seasonal and spatial variations. Seasonal variations were related to changes in freshwater discharge following the hydrological cycle, with highest concentrations of CO2, CH4, N2O during low water owing to a longer water residence time and lower currents (i.e. lower gas transfer velocities), both contributing to the accumulation of gases in the water column, combined with higher temperatures favourable to microbial processes. Inter-annual differences of discharge also led to differences in CH4 and N2O that were higher in years with prolonged low water periods. Spatial variations were mostly due to differences in land cover over the catchments, with systems dominated by agriculture (croplands and pastures) having higher CO2, CH4, N2O levels than forested systems. This seemed to be related to higher levels of dissolved and particulate organic matter, as well as dissolved inorganic nitrogen in agriculture dominated systems compared to forested ones. Groundwater had very low CH4 concentrations in the shallow and unconfined aquifers (mostly fractured limestones) of the Meuse basin, hence, should not contribute significantly to the high CH4 levels in surface riverine waters. Owing to high dissolved concentrations, groundwater could potentially transfer important quantities of CO2 and N2O to surface waters of the Meuse basin, although this hypothesis remains to be tested

    Efficacy of Second-Line Chemotherapy after a First-Line Triplet in Patients with Metastatic Colorectal Cancer

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    Background: Exposing patients with metastatic colorectal cancer (MCRC) to all three active chemotherapeutic agents (oxaliplatin, irinotecan, fluorouracil) has improved survival. The benefit of second-line chemotherapy after a first-line triplet is not clearly defined. We evaluated the efficacy of second-line chemotherapy in patients who had received first-line triplet therapy. Methods: The medical records of patients treated on a prospective trial of first-line triplet therapy were reviewed for second-line treatment. Univariate and multivariate analyses were performed to establish factors of prognostic significance. Results: Of the 53 patients who received first-line triplet therapy, 28 (53%) received second-line chemotherapy [13 men; 8 with a colon primary; mutant KRAS in 10, wild-type in 15, and unknown status in 3; Eastern Cooperative Oncology Group performance status (PS) of 1 in 16 patients, PS 2 in 3, PS 3 in 2, and unknown in 7; involved organs: liver in 17 patients, lung in 16, and peritoneum in 8]. Second-line chemotherapy consisted of XELOX or FOLFOX in 13 patients, XELIRI or FOLFIRI in 12, and single-agent irinotecan in 3. Concurrent bevacizumab was given in 16 patients (57%), and cetuximab, in 2 (7%). Median survival was 28.0 months [95% confidence interval (CI): 22.8 months to 33.2 months] for patients receiving second-line therapy and 23.0 months (95% CI: 13.2 months to 32.8 months) for those not receiving it. Best response was partial in 6 patients (21%), stable disease in 11 (39%), and progressive disease in 11 (39%). Median progression-free survival was 4.8 months (95% CI: 2.4 months to 9.6 months), and overall survival was 15 months (95% CI: 9.6 months to 20.4 months). Conclusions: Second-line chemotherapy after first-line triplet therapy in MCRC is feasible and suggests efficacy comparable to that reported for second-line therapy after a doublet, regardless of the agent used

    Understanding the Radial Force of Stroke Thrombectomy Devices to Minimize Vessel Wall Injury: Mechanical Bench Testing of the Radial Force Generated by a Novel Braided Thrombectomy Assist Device Compared to Laser-Cut Stent Retrievers in Simulated MCA Vessel Diameters

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    Background: Recent reports have raised various concerns about the risk of vessel wall injury while withdrawing current laser-cut stent retrievers during active strut apposition to the vessel walls. The development of braided thrombectomy assist devices in conjunction with aspiration systems may be gentler on the fragile brain vessels and more optimized with regard to the radial force (RF) for vessel diameters of proximal (M1) and distal (M2) large vessel occlusions (LVOs). Methods: Mechanical bench testing of the RF was performed using a radial compression station mounted on a tensile testing machine. The total RF in newtons (N) generated in vessels with diameters ranging from 2.25 to 3 mm as seen in proximal LVOs (∼M1), and in vessel diameters ranging from 1.5 to 2.24 mm as seen in distal LVOs (∼M2), was measured. The outer diameter of each stent was recorded, and an RF ≤1 N was grouped as low, while an RF \u3e1 N was grouped as high for this analysis. Results: The total RFs of all laser-cut stent retrievers were all higher in the simulated M2 vessels (\u3e1 N) than in the M1 vessels (\u3c1 N), whereas the total RFs of the braided thrombectomy assist devices were uniformly low in both the simulated M1 and the simulated M2 vessels. Conclusions: Novel braided thrombectomy assist devices in conjunction with aspiration systems have lower RFs than existing laser-cut stent retrievers in M1 and M2 vessel diameters. Further in vivo studies are needed to delineate the impact of lowering the RF on vessel wall integrity

    Effects of agricultural land use on fluvial carbon dioxide, methane and nitrous oxide concentrations in a large European river, the Meuse (Belgium)

    No full text
    We report a data-set of CO2, CH4, and N2O concentrations in the surface waters of the Meuse river network in Belgium, obtained during four surveys covering 50 stations (summer 2013 and late winter 2013, 2014 and 2015), from yearly cycles in four rivers of variable size and catchment land cover, and from 111 groundwater samples. Surface waters of the Meuse river network were over-saturated in CO2, CH4, N2O with respect to atmospheric equilibrium, acting as sources of these greenhouse gases to the atmosphere, although the dissolved gases also showed marked seasonal and spatial variations. Seasonal variations were related to changes in freshwater discharge following the hydrological cycle, with highest concentrations of CO2, CH4, N2O during low water owing to a longer water residence time and lower currents (i.e. lower gas transfer velocities), both contributing to the accumulation of gases in the water column, combined with higher temperatures favourable to microbial processes. Inter-annual differences of discharge also led to differences in CH4 and N2O that were higher in years with prolonged low water periods. Spatial variations were mostly due to differences in land cover over the catchments, with systems dominated by agriculture (croplands and pastures) having higher CO2, CH4, N2O levels than forested systems. This seemed to be related to higher levels of dissolved and particulate organic matter, as well as dissolved inorganic nitrogen in agriculture dominated systems compared to forested ones. Groundwater had very low CH4 concentrations in the shallow and unconfined aquifers (mostly fractured limestones) of the Meuse basin, hence, should not contribute significantly to the high CH4 levels in surface riverine waters. Owing to high dissolved concentrations, groundwater could potentially transfer important quantities of CO2 and N2O to surface waters of the Meuse basin, although this hypothesis remains to be tested

    The heartbeat evoked potential does not support strong interoceptive sensibility in trait mindfulness.

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    The enhancement of body awareness is proposed as one of the cognitive mechanisms that characterize mindfulness. To date, this hypothesis is supported by self-report and behavioral measures but still lacks physiological evidence. The current study investigated relation between trait mindfulness (i.e., individual differences in the ability to be mindful in daily life) and body awareness in combining a self-report measure (Multidimensional Assessment of Interoceptive Awareness [MAIA] questionnaire) with analysis of the heartbeat evoked potential (HEP), which is an event-related potential reflecting the cortical processing of the heartbeat. The HEP data were collected from 17 healthy participants under five minutes of resting-state condition. In addition, each participant completed the Freiburg Mindfulness Inventory and the MAIA questionnaire. Taking account of the important variability of HEP effects, analyses were replicated with the same participants three times (in three distinct sessions). First, group-level analyses showed that HEP amplitude and trait mindfulness do not correlate. Secondly, we observed that HEP amplitude could positively correlate with self-reported body awareness; however, this association was unreliable over time. Interestingly, we found that HEP measure shows very poor reliability over time at the individual level, potentially explaining the lack of reliable association between HEP and psychological traits. Lastly, a reliable positive correlation was found between self-reported trait mindfulness and body awareness. Taken together, these findings provide preliminary evidence that the HEP might not support the increased subjective body awareness in trait mindfulness, thus suggesting that perhaps objective and subjective measures of body awareness could be independent. This is the pre-peer reviewed version of the following article: Verdonk, C., Trousselard, M., Di Bernardi Luft, C., Medani, T., Billaud, J.-B., Ramdani, C., Canini, F., Claverie, D., Jaumard-Hakoun, A., & Vialatte, F. (2021). The heartbeat evoked potential does not support strong interoceptive sensibility in trait mindfulness. Psychophysiology, 00, 1– 13. https://doi.org/10.1111/psyp.13891, which has been published in final form at https://doi.org/10.1111/psyp.13891. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions
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