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1.
  • Thomas, HS, et al. (author)
  • 2019
  • swepub:Mat__t
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2.
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3.
  • Oonk, M. H. M., et al. (author)
  • Radiotherapy Versus Inguinofemoral Lymphadenectomy as Treatment for Vulvar Cancer Patients With Micrometastases in the Sentinel Node: Results of GROINSS-V II
  • 2021
  • In: Journal of Clinical Oncology. - : American Society of Clinical Oncology (ASCO). - 0732-183X .- 1527-7755. ; 39:32
  • Journal article (peer-reviewed)abstract
    • PURPOSE The Groningen International Study on Sentinel nodes in Vulvar cancer (GROINSS-V)-II investigated whether inguinofemoral radiotherapy is a safe alternative to inguinofemoral lymphadenectomy (IFL) in vulvar cancer patients with a metastatic sentinel node (SN). METHODS GROINSS-V-II was a prospective multicenter phase-II single-arm treatment trial, including patients with early-stage vulvar cancer (diameter < 4 cm) without signs of lymph node involvement at imaging, who had primary surgical treatment (local excision with SN biopsy). Where the SN was involved (metastasis of any size), inguinofemoral radiotherapy was given (50 Gy). The primary end point was isolated groin recurrence rate at 24 months. Stopping rules were defined for the occurrence of groin recurrences. RESULTS From December 2005 until October 2016, 1,535 eligible patients were registered. The SN showed metastasis in 322 (21.0%) patients. In June 2010, with 91 SN-positive patients included, the stopping rule was activated because the isolated groin recurrence rate in this group went above our predefined threshold. Among 10 patients with an isolated groin recurrence, nine had SN metastases > 2 mm and/or extracapsular spread. The protocol was amended so that those with SN macrometastases (> 2 mm) underwent standard of care (IFL), whereas patients with SN micrometastases (<= 2 mm) continued to receive inguinofemoral radiotherapy. Among 160 patients with SN micrometastases, 126 received inguinofemoral radiotherapy, with an ipsilateral isolated groin recurrence rate at 2 years of 1.6%. Among 162 patients with SN macrometastases, the isolated groin recurrence rate at 2 years was 22% in those who underwent radiotherapy, and 6.9% in those who underwent IFL (P = .011). Treatment-related morbidity after radiotherapy was less frequent compared with IFL. CONCLUSION Inguinofemoral radiotherapy is a safe alternative for IFL in patients with SN micrometastases, with minimal morbidity. For patients with SN macrometastasis, radiotherapy with a total dose of 50 Gy resulted in more isolated groin recurrences compared with IFL. (C) 2021 by American Society of Clinical Oncology
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4.
  • Van der Kolk, W. L., et al. (author)
  • Unilateral inguinofemoral lymphadenectomy in patients with early-stage vulvar squamous cell carcinoma and a unilateral metastatic sentinel lymph node is safe
  • 2022
  • In: Gynecologic Oncology. - : Elsevier BV. - 0090-8258 .- 1095-6859. ; 167:1, s. 3-10
  • Journal article (peer-reviewed)abstract
    • Objective. Optimal management of the contralateral groin in patients with early-stage vulvar squamous cell carcinoma (VSCC) and a metastatic unilateral inguinal sentinel lymph node (SN) is unclear. We analyzed patients who participated in GROINSS-V I or II to determine whether treatment of the contralateral groin can safely be omitted in patients with a unilateral metastatic SN.Methods. We selected the patients with a unilateral metastatic SN from the GROINSS-V I and II databases. We determined the incidence of contralateral additional non-SN metastases in patients with unilateral SN-metastasis who underwent bilateral inguinofemoral lymphadenectomy (IFL). In those who underwent only ipsilateral groin treatment or no further treatment, we determined the incidence of contralateral groin recurrences during follow-up.Results. Of 1912 patients with early-stage VSCC, 366 had a unilateral metastatic SN. Subsequently, 244 had an IFL or no treatment of the contralateral groin. In seven patients (7/244; 2.9% [95% CI: 1.4%-5.8%]) disease was di-agnosed in the contralateral groin: five had contralateral non-SN metastasis at IFL and two developed an isolated contralateral groin recurrence after no further treatment. Five of them had a primary tumor >= 30 mm. Bilateral ra-diotherapy was administered in 122 patients, of whom one (1/122; 0.8% [95% CI: 0.1%-4.5%]) had a contralateral groin recurrence.Conclusion. The risk of contralateral lymph node metastases in patients with early-stage VSCC and a unilateral metastatic SN is low. It appears safe to limit groin treatment to unilateral IFL or inguinofemoral radiotherapy in these cases.(c) 2022 The Authors. Published by Elsevier Inc. This is an open access article under the CC BY license (http:// creativecommons.org/licenses/by/4.0/).
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5.
  • Ademuyiwa, Adesoji O., et al. (author)
  • Determinants of morbidity and mortality following emergency abdominal surgery in children in low-income and middle-income countries
  • 2016
  • In: BMJ Global Health. - : BMJ Publishing Group Ltd. - 2059-7908. ; 1:4
  • Journal article (peer-reviewed)abstract
    • Background: Child health is a key priority on the global health agenda, yet the provision of essential and emergency surgery in children is patchy in resource-poor regions. This study was aimed to determine the mortality risk for emergency abdominal paediatric surgery in low-income countries globally.Methods: Multicentre, international, prospective, cohort study. Self-selected surgical units performing emergency abdominal surgery submitted prespecified data for consecutive children aged <16 years during a 2-week period between July and December 2014. The United Nation's Human Development Index (HDI) was used to stratify countries. The main outcome measure was 30-day postoperative mortality, analysed by multilevel logistic regression.Results: This study included 1409 patients from 253 centres in 43 countries; 282 children were under 2 years of age. Among them, 265 (18.8%) were from low-HDI, 450 (31.9%) from middle-HDI and 694 (49.3%) from high-HDI countries. The most common operations performed were appendectomy, small bowel resection, pyloromyotomy and correction of intussusception. After adjustment for patient and hospital risk factors, child mortality at 30 days was significantly higher in low-HDI (adjusted OR 7.14 (95% CI 2.52 to 20.23), p<0.001) and middle-HDI (4.42 (1.44 to 13.56), p=0.009) countries compared with high-HDI countries, translating to 40 excess deaths per 1000 procedures performed.Conclusions: Adjusted mortality in children following emergency abdominal surgery may be as high as 7 times greater in low-HDI and middle-HDI countries compared with high-HDI countries. Effective provision of emergency essential surgery should be a key priority for global child health agendas.
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6.
  • Men'shchikov, A., et al. (author)
  • Filamentary structures and compact objects in the Aquila and Polaris clouds observed by Herschel
  • 2010
  • In: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 518, s. L103-
  • Journal article (peer-reviewed)abstract
    • Our PACS and SPIRE images of the Aquila Rift and part of the Polaris Flare regions, taken during the science demonstration phase of Herschel discovered fascinating, omnipresent filamentary structures that appear to be physically related to compact cores. We briefly describe a new multi-scale, multi-wavelength source extraction method used to detect objects and measure their parameters in our Herschel images. All of the extracted starless cores (541 in Aquila and 302 in Polaris) appear to form in the long and very narrow filaments. With its combination of the far-IR resolution and sensitivity, Herschel directly reveals the filaments in which the dense cores are embedded; the filaments are resolved and have deconvolved widths of similar to 35 '' in Aquila and similar to 59 '' in Polaris (similar to 9000 AU in both regions). Our first results of observations with Herschel enable us to suggest that in general dense cores may originate in a process of fragmentation of complex networks of long, thin filaments, likely formed as a result of an interplay between gravity, interstellar turbulence, and magnetic fields. To unravel the roles of the processes, one has to obtain additional kinematic and polarization information; these follow-up observations are planned.
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7.
  • Oonk, Maaike H. M., et al. (author)
  • Radiotherapy Versus Inguinofemoral Lymphadenectomy as Treatment for Vulvar Cancer Patients With Micrometastases in the Sentinel Node : Results of GROINSS-V II
  • 2021
  • In: Journal of Clinical Oncology. - : Lippincott, Williams & Wilkins. - 0732-183X .- 1527-7755. ; 39:32, s. 3623-3632
  • Journal article (peer-reviewed)abstract
    • PURPOSE The Groningen International Study on Sentinel nodes in Vulvar cancer (GROINSS-V)-II investigated whether inguinofemoral radiotherapy is a safe alternative to inguinofemoral lymphadenectomy (IFL) in vulvar cancer patients with a metastatic sentinel node (SN). METHODS GROINSS-V-II was a prospective multicenter phase-II single-arm treatment trial, including patients with early-stage vulvar cancer (diameter < 4 cm) without signs of lymph node involvement at imaging, who had primary surgical treatment (local excision with SN biopsy). Where the SN was involved (metastasis of any size), inguinofemoral radiotherapy was given (50 Gy). The primary end point was isolated groin recurrence rate at 24 months. Stopping rules were defined for the occurrence of groin recurrences. RESULTS From December 2005 until October 2016, 1,535 eligible patients were registered. The SN showed metastasis in 322 (21.0%) patients. In June 2010, with 91 SN-positive patients included, the stopping rule was activated because the isolated groin recurrence rate in this group went above our predefined threshold. Among 10 patients with an isolated groin recurrence, nine had SN metastases > 2 mm and/or extracapsular spread. The protocol was amended so that those with SN macrometastases (> 2 mm) underwent standard of care (IFL), whereas patients with SN micrometastases (<= 2 mm) continued to receive inguinofemoral radiotherapy. Among 160 patients with SN micrometastases, 126 received inguinofemoral radiotherapy, with an ipsilateral isolated groin recurrence rate at 2 years of 1.6%. Among 162 patients with SN macrometastases, the isolated groin recurrence rate at 2 years was 22% in those who underwent radiotherapy, and 6.9% in those who underwent IFL (P = .011). Treatment-related morbidity after radiotherapy was less frequent compared with IFL. CONCLUSION Inguinofemoral radiotherapy is a safe alternative for IFL in patients with SN micrometastases, with minimal morbidity. For patients with SN macrometastasis, radiotherapy with a total dose of 50 Gy resulted in more isolated groin recurrences compared with IFL.
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8.
  • Attard, Karl M., et al. (author)
  • Metabolism of a subtidal rocky mussel reef in a high-temperate setting : pathways of organic C flow
  • 2020
  • In: Marine Ecology Progress Series. - : Inter-Research Science Center. - 0171-8630 .- 1616-1599. ; 645, s. 41-54
  • Journal article (peer-reviewed)abstract
    • Mytilid mussels form abundant, species-rich reefs on rocky substrates, but the role of this key habitat in carbon (C) cycling remains poorly understood. We performed a seasonal study on a 5 m deep photic Mytilus trossulus reef in the Central Baltic Sea to investigate pathways and rates of organic C flow. Reef gross primary production (GPP) and respiration (R) were estimated seasonally using underwater O2 eddy covariance on hourly and daily timescales. Photogrammetry and biotic sampling were used to quantify reef rugosity and mussel coverage, and to derive mussel filtration and biodeposition. Mussels were highly abundant, reaching ~50000 ind. m-2, and the reef structure increased the seabed surface area by 44%. GPPhourly was up to 20 mmol O2 m-2 h-1 and GPPdaily was up to 107 mmol O2 m-2 d-1, comparable to a nearby seagrass canopy. Hourly eddy fluxes responded linearly to light intensity and flow velocity, with higher velocities enhancing reef O2 uptake at night. Reef Rdaily exceeded GPPdaily on 12 of 13 measurement days, and Rannual (29 mol O2 m-2 yr-1) was 3-fold larger than GPPannual. The reef sustained a productive community of microbes and fauna whose activities accounted for ~50% of Rannual. Horizontal water advection promoted food supply to the reef and likely facilitated substantial lateral C export of mussel biodeposits. Our analyses suggest that a reduction in mussel reef extent due to ongoing environmental change will have major implications for the transport and transformation of C and nutrients within the coastal Baltic Sea.
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9.
  • Carbajal, Ricardo, et al. (author)
  • Pain Assessment In Ventilated And Non-ventilated Neonates In Nicus Across Europe : European Pain Audit In Neonates (europain Survey)
  • 2014
  • In: Archives of Disease in Childhood. - London, United Kingdom : BMJ Publishing Group Ltd. - 0003-9888 .- 1468-2044. ; 99, s. A68-A68
  • Journal article (peer-reviewed)abstract
    • Background: Neonates undergo many painful procedures during their NICU stay. These may include tracheal intubation/ventilation, skin-breaking procedures, drainage/suctioning of body orifices or cavities. Inherent subjectivity and difficulties of neonatal pain assessment contribute to a wide variety of assessment tools and clinical practices. To date, these practices have been not studied at a large scale.Objective: To determine current clinical practices for neonatal pain assessment in NICUs across Europe.Methods: An epidemiological observational study on bedside pain assessment practices collected data for all neonates in participating NICUs until infants left the unit (discharge, death, transfer to another hospital) or for 28 days. Data collection occurred via an online database for 1 month at each NICU. All neonates up to a gestational age of 44 weeks were included.Results: From October 2012 to June 2013, 243 NICUs from 18 European countries collected pain assessment data in 6680 neonates. Of these, 2142 received tracheal ventilation (TV), 1496 non-invasive ventilation (NIV) and 3042 only spontaneous ventilation (SV). The median (IQR) gestational age of TV, NIV and SV neonates were 32.1 (28.1–37.4), 33.6 (31.0–36.6) and 37.9 (35.0–39.9), respectively (p < 0.001). Overall, 58.5% of TV neonates, 45.0% of NIV neonates and 30.4% of SV neonates received bedside pain assessments (p < 0.001). Fig. shows pain assessments by country.Conclusions: Over half (58.5%) of TV neonates and less than half (45.0%) of NIV neonates had pain assessments performed in European NICUs. Wide variations in the rates of pain assessment exist among countries and an important improvement seems necessary.
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10.
  • Carbajal, Ricardo, et al. (author)
  • Sedation And Analgesia For Neonates In Nicus Across Europe : The Europain Survey
  • 2014
  • In: Archives of Disease in Childhood. - London, United Kingdom : BMJ Publishing Group Ltd. - 0003-9888 .- 1468-2044. ; 99, s. A64-A64
  • Journal article (peer-reviewed)abstract
    • Background: Pain and stress induced by mechanical ventilation, invasive procedures, or painful diseases supports the use of sedation/analgesia (S/A) in newborns admitted to Neonatal Intensive Care Units (NICUs). To date, these practices have not been studied at a large scale.Objective: To determine current clinical practices regarding the use of S/A drugs in NICUs across Europe.Methods: This epidemiological observational study on bedside clinical practices regarding S/A collected data for all neonates in participating NICUs until the infant left the unit (discharge, death, transfer) or for up to 28 days. Data collection occurred via an online database for 1 month at each NICU. All neonates up to 44 weeks gestation were included.Results: From October 2012 to June 2013, 243 NICUs from 18 European countries collected data on 6680 eligible neonates. Of these, 2142 received tracheal ventilation (TV), 1496 non-invasive ventilation (NIV) and 3042 only spontaneous ventilation (SV). The median (IQR) gestational age of TV, NIV and SV neonates were 32.1 (28.1–37.4), 33.6 (31.0–36.6) and 37.9 (35.0–39.9), respectively (p < 0.001). Overall, more TV neonates [81.5% (n = 1746)] received S/A drugs than NIV neonates [17.8% (n = 266)] and SV neonates [9.3% (n = 282)]; p < 0.001. Fig. shows the rate of S/A use by country; table shows S/A drugs used.Conclusions: Most ventilated but few non-ventilated neonates (NIV and SV) receive S/A therapy in European NICUs. Wide variations in S/A use, drugs used, and mode of administration (continuous, bolus, or both) exist among countries.
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11.
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12.
  • Rodil, Iván F., et al. (author)
  • Macrofauna communities across a seascape of seagrass meadows : environmental drivers, biodiversity patterns and conservation implications
  • 2021
  • In: Biodiversity and Conservation. - : Springer Science and Business Media LLC. - 0960-3115 .- 1572-9710. ; :30, s. 3023-3043
  • Journal article (peer-reviewed)abstract
    • Similar to other coastal biogenic habitats (e.g. tidal marshes, kelp forests, mangroves and coral reefs), a key function of seagrass meadows is the enhancement of biodiversity. Variability at multiple spatial scales is a driver of biodiversity, but our understanding of the response of macrofauna communities to variability of seagrass meadows is limited. We examined the macrofauna community structure (abundance and biomass) and diversity patterns (α- and β-diversity) across a seascape gradient of eleven seagrass meadows differing in the number, composition and density of plant species. The variability of the macrobenthic communities was regulated by a combination of sedimentary (mainly for the infauna) and macrophyte (mainly for the epifauna) predictors. We demonstrate that the natural occurrence of drifting algae trapped in the aboveground complexity of the meadows benefits seagrass macrofauna. Seagrass-associated macrofauna showed a clear increase in abundance and α-diversity metrics with increasing habitat complexity attributes (i.e. shoot density, plant biomass and canopy height). Furthermore, partitioning of β-diversity (i.e. the variation of species composition between sites) implied the replacement of some species by others between sites (i.e. spatial turnover) instead of a process of species loss (or gain) from site to site (i.e. nestedness). Therefore, the enhancement of macrofauna diversity across an increasing gradient of seagrass complexity, and the dominance of the turnover component suggest that devoting conservation efforts on many different types of meadows, including the less diverse, should be a priority for coastal habitat-management.
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13.
  • Rodil, Iván F., et al. (author)
  • Positive contribution of macrofaunal biodiversity to secondary production and seagrass carbon metabolism
  • 2022
  • In: Ecology. - : Wiley. - 0012-9658 .- 1939-9170. ; 103:4
  • Journal article (peer-reviewed)abstract
    • Coastal vegetated habitats such as seagrasses are known to play a critical role in carbon cycling and the potential to mitigate climate change, as blue carbon habitats have been repeatedly highlighted. However, little information is known about the role of associated macrofauna communities on the dynamics of critical processes of seagrass carbon metabolism (e.g., respiration, turnover, and production). We conducted a field study across a spatial gradient of seagrass meadows involving variable environmental conditions and macrobenthic diversity to investigate (1) the relationship between macrofauna biodiversity and secondary production (i.e., consumer incorporation of organic matter per time unit), and (2) the role of macrofauna communities in seagrass organic carbon metabolism (i.e., respiration and primary production). We show that, although several environmental factors influence secondary production, macrofauna biodiversity controls the range of local seagrass secondary production. We demonstrate that macrofauna respiration rates were responsible for almost 40% of the overall seafloor community respiration. Macrofauna represented on average >25% of the total benthic organic C stocks, high secondary production that is likely to become available to upper trophic levels of the coastal food web. Our findings support the role of macrofauna biodiversity in maintaining productive ecosystems, implying that biodiversity loss due to ongoing environmental change yields less productive seagrass ecosystems. Therefore, the assessment of carbon dynamics in coastal habitats should include associated macrofauna biodiversity elements if we aim to obtain robust estimates of global carbon budgets required to implement management actions for the sustainable functioning of the world's coasts.
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14.
  • Stief, Peter, et al. (author)
  • Intracellular nitrate storage by diatoms can be an important nitrogen pool in freshwater and marine ecosystems
  • 2022
  • In: Communications Earth and Environment. - : Springer Science and Business Media LLC. - 2662-4435. ; 3:1
  • Journal article (peer-reviewed)abstract
    • Identifying and quantifying nitrogen pools is essential for understanding the nitrogen cycle in aquatic ecosystems. The ubiquitous diatoms represent an overlooked nitrate pool as they can accumulate nitrate intracellularly and utilize it for nitrogen assimilation, dissipation of excess photosynthetic energy, and Dissimilatory Nitrate Reduction to Ammonium (DNRA). Here, we document the global co-occurrence of diatoms and intracellular nitrate in phototrophic microbial communities in freshwater (n = 69), coastal (n = 44), and open marine (n = 4) habitats. Diatom abundance and total intracellular nitrate contents in water columns, sediments, microbial mats, and epilithic biofilms were highly significantly correlated. In contrast, diatom community composition had only a marginal influence on total intracellular nitrate contents. Nitrate concentrations inside diatom cells exceeded ambient nitrate concentrations ∼100–4000-fold. The collective intracellular nitrate pool of the diatom community accounted for <1% of total nitrate in pelagic habitats and 65–95% in benthic habitats. Accordingly, nitrate-storing diatoms are emerging as significant contributors to benthic nitrogen cycling, in particular through Dissimilatory Nitrate Reduction to Ammonium activity under anoxic conditions.
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15.
  • Anand, Kanwlajeet J. S., et al. (author)
  • Assessment of continuous pain in newborns admitted to NICUs in 18 European countries
  • 2017
  • In: Acta Paediatrica. - : John Wiley & Sons. - 0803-5253 .- 1651-2227. ; 106:8, s. 1248-1259
  • Journal article (peer-reviewed)abstract
    • Aim: Continuous pain occurs routinely, even after invasive procedures, or inflammation and surgery, but clinical practices associated with assessments of continuous pain remain unknown.Methods: A prospective cohort study in 243 Neonatal Intensive Care Units (NICUs) from 18 European countries recorded frequency of pain assessments, use of mechanical ventilation, sedation, analgesia, or neuromuscular blockade for each neonate upto 28 days after NICU admission.Results: Only 2113/6648 (31·8%) of neonates received assessments of continuous pain, occurring variably among tracheal ventilation (TrV, 46·0%), noninvasive ventilation (NiV, 35·0%), and no ventilation (NoV, 20·1%) groups (p<0·001). Daily assessments for continuous pain occurred in only 10·4% of all neonates (TrV: 14·0%, NiV: 10·7%, NoV: 7·6%; p<0·001). More frequent assessments of continuous pain occurred in NICUs with pain guidelines, nursing champions, and surgical admissions prompted (all p<0·01), and for newborns <32 weeks gestational age, those requiring ventilation, or opioids, sedatives-hypnotics, general anesthetics (O-SH-GA) (all p<0·001), or surgery (p=0·028). Use of O-SH-GA drugs increased the odds for pain assessment in the TrV (OR:1·60, p<0·001) and NiV groups (OR:1·40, p<0·001).Conclusion: Assessments of continuous pain occurred in less than one-third of NICU admissions, and daily in only 10% of neonates. NICU clinical practices should consider including routine assessments of continuous pain in newborns.
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16.
  • Attard, Karl M., et al. (author)
  • Benthic oxygen exchange in a live coralline algal bed and an adjacent sandy habitat : an eddy covariance study
  • 2015
  • In: Marine Ecology Progress Series. - : Inter-Research. - 0171-8630 .- 1616-1599. ; 535, s. 99-115
  • Journal article (peer-reviewed)abstract
    • Coralline algal (maerl) beds are widespread, slow-growing, structurally complex perennial habitats that support high biodiversity, yet are significantly understudied compared to seagrass beds or kelp forests. We present the first eddy covariance (EC) study on a live maerl bed, assessing the community benthic gross primary productivity (GPP), respiration (R), and net ecosystem metabolism (NEM) derived from diel EC time series collected during 5 seasonal measurement campaigns in temperate Loch Sween, Scotland. Measurements were also carried out at an adjacent (similar to 20 m distant) permeable sandy habitat. The O-2 exchange rate was highly dynamic, driven by light availability and the ambient tidally-driven flow velocity. Linear relationships between the EC O-2 fluxes and available light indicate that the benthic phototrophic communities were light limited. Compensation irradiance (E-c) varied seasonally and was typically similar to 1.8-fold lower at the maerl bed compared to the sand. Substantial GPP was evident at both sites; however, the maerl bed and the sand habitat were net heterotrophic during each sampling campaign. Additional inputs of similar to 4 and similar to 7 mol m(-2) yr(-1) of carbon at the maerl bed and sand site, respectively, were required to sustain the benthic O-2 demand. Thus, the 2 benthic habitats efficiently entrap organic carbon and are sinks of organic material in the coastal zone. Parallel deployment of 0.1 m(2) benthic chambers during nighttime revealed O-2 uptake rates that varied by up to similar to 8-fold between replicate chambers (from -0.4 to -3.0 mmol O-2 m(-2) h(-1); n = 4). However, despite extensive O-2 flux variability on meter horizontal scales, mean rates of O-2 uptake as resolved in parallel by chambers and EC were typically within 20% of one another.
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17.
  • Attard, Karl M., et al. (author)
  • Seasonal ecosystem metabolism across shallow benthic habitats measured by aquatic eddy covariance
  • 2019
  • In: Limnology and Oceanography Letters. - : Wiley. - 2378-2242. ; 4:3, s. 79-86
  • Journal article (peer-reviewed)abstract
    • Shallow benthic habitats are hotspots for carbon cycling and energy flow, but metabolism (primary production and respiration) dynamics and habitat-specific differences remain poorly understood. We investigated daily, seasonal, and annual metabolism in six key benthic habitats in the Baltic Sea using similar to 2900h of in situ aquatic eddy covariance oxygen flux measurements. Rocky substrates had the highest metabolism rates. Habitat-specific annual primary production per m(2) was in the order Fucus vesiculosus canopy>Mytilus trossulus reef>Zostera marina canopy>mixed macrophytes canopy>sands, whereas respiration was in the order M. trossulus>F. vesiculosus>Z. marina>mixed macrophytes> sands>aphotic sediments. Winter metabolism contributed 22-31% of annual rates. Spatial upscaling revealed that benthic habitats drive >90% of ecosystem metabolism in waters <= 5 m depth, highlighting their central role in carbon and nutrient cycling in shallow waters.
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18.
  • Attard, K. M., et al. (author)
  • Seasonal metabolism and carbon export potential of a key coastal habitat : The perennial canopy-forming macroalga Fucus vesiculosus
  • 2019
  • In: Limnology and Oceanography. - : Wiley. - 0024-3590 .- 1939-5590. ; 64:1, s. 149-164
  • Journal article (peer-reviewed)abstract
    • The important role of macroalgal canopies in the oceanic carbon (C) cycle is increasingly being recognized, but direct assessments of community productivity remain scarce. We conducted a seasonal study on a sublittoral Baltic Sea canopy of the brown alga Fucus vesiculosus, a prominent species in temperate and Arctic waters. We investigated community production on hourly, daily, and seasonal timescales. Aquatic eddy covariance (AEC) oxygen flux measurements integrated similar to 40 m(2) of the seabed surface area and documented considerable oxygen production by the canopy year-round. High net oxygen production rates of up to 35 +/- 9 mmol m(-2) h(-1) were measured under peak irradiance of similar to 1200 mu mol photosynthetically active radiation (PAR) m(-2) s(-1) in summer. However, high rates > 15 mmol m(-2) h(-1) were also measured in late winter (March) under low light intensities < 250 mu mol PAR m(-2) s(-1) and water temperatures of similar to 1 degrees C. In some cases, hourly AEC fluxes documented an apparent release of oxygen by the canopy under dark conditions, which may be due to gas storage dynamics within internal air spaces of F. vesiculosus. Daily net ecosystem metabolism (NEM) was positive (net autotrophic) in all but one of the five measurement campaigns (December). A simple regression model predicted a net autotrophic canopy for two-thirds of the year, and annual canopy NEM amounted to 25 mol O-2 m(-2) yr(-1), approximately six-fold higher than net phytoplankton production. Canopy C export was similar to 0.3 kg C m(-2) yr(-1), comparable to canopy standing biomass in summer. Macroalgal canopies thus represent regions of intensified C assimilation and export in coastal waters.
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19.
  • Attard, P, et al. (author)
  • Dynamic surface force measurement. I. van der Waals collisions
  • 1999
  • In: Review of Scientific Instruments. - 0034-6748 .- 1089-7623. ; 69, s. 3852-3866
  • Journal article (peer-reviewed)abstract
    • Theoretical calculations and experimental measurements are used to show that hitherto neglected inertial effects can be significant in computer- controlled surface force measurement devices such as the atomic force microscope. The problem is analyzed in detail for the case of the van der Waals attraction in air. It is demonstrated that equating the cantilever deflection to the surface force systematically underestimates the magnitude of the surface force, increasingly so as the speed of approach is increased. It is also shown that the surface separation becomes lost at high accelerations due to a dynamic uncoupling of the cantilever deflection and angle. The effects of elastic deformation of the bodies are taken into account, including the collision-induced elastic vibrations in the solids. Experimental data are obtained for the van der Waals attraction and collision of glass surfaces in air using the measurement and analysis of surface forces device. All of the effects found in the theoretical calculations are identified in the experimental data.
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20.
  • Attard, Thohmas. M., et al. (author)
  • Supercritical extraction as an effective first-step in a maize stover biorefinery
  • 2015
  • In: RSC Advances. - : Royal Society of Chemistry. - 2046-2069. ; 5:54, s. 43831-43838
  • Journal article (peer-reviewed)abstract
    • Supercritical carbon dioxide (scCO2) has been investigated for the generation of valuable waxy compounds and as an added-value technology in a holistic maize stover biorefinery. ScCO2 extraction and fractionation was carried out prior to hydrolysis and fermentation of maize stover. Fractionation of the crude extracts by scCO2 resulted in wax extracts having different compositions and melting temperatures, enabling their utilisation in different applications. One such fraction demonstrated significant potential as a renewable defoaming agent in washing machine detergent formulations. Furthermore, scCO2 extraction has been shown to have a positive effect on the downstream processing of the maize stover. Fermentation of the scCO2 extracted maize stover hydrolysates exhibited a higher glucose consumption and greater potential growth for surfactant (in comparison with non-scCO2 treated stover) axnd ethanol production (a 40% increase in overall ethanol production after scCO2 pre-treatment). This work represents an important development in the extraction of high value components from low value wastes and demonstrates the benefits of using scCO2 extraction as a first-step in biomass processing, including enhancing downstream processing of the biomass for the production of 2nd generation biofuels as part of an integrated holistic biorefinery.
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21.
  • Carbajal, Ricardo, et al. (author)
  • Pain Assessment in Ventilated and Non-Ventilated Neonates in NICUS across Europe : Results from the EUROPAIN Study
  • 2016
  • Conference paper (peer-reviewed)abstract
    • Aim of Investigation: Pain from invasive or noninvasive procedures, mechanical ventilation, or painful medical and surgical conditions is commonplace in neonatal intensive care units (NICUs). While prevention and treatment of neonatal pain seem essential, an adequate analgesic approach cannot be implemented without relevant and timely pain assessments. Data on neonatal pain assessment practices are scarce, with undefined best practices or clinical benefits. We aimed to describe pain assessment practices in 243 NICUs from 18 European countries and to examine the NICU and patient characteristics influencing pain assessments at the bedside.Methods: Demographic data, modes of respiration, use of sedation, analgesia, or neuromuscular blockers, frequency and types of pain assessments were recorded for all newborns during the first 28 days of NICU admission. Multivariable models tested the associations between the performance of pain assessments and center and neonatal factors.Results: Among 6648 neonates enrolled, highest level of ventilation during the study period classified patients into tracheal ventilation (TV, n=2138 [32%]), non-invasive ventilation (NIV, n=1493 [23%]), and spontaneous ventilation groups (SV, n=3017 [45%]). Pain assessments were performed in 1250 (58%), 672 (45%), and 916 (30%) of these groups respectively (p<0.001). Using data from 78,742 patient-days, we found that 2,838 (43%) neonates received 4.3 (5.2) pain assessments per neonate and per day (median (IQR): 2.4 (1-5)), whereas 3810 (57%) neonates did not receive any pain assessments. Pain assessments occurred on every day of the NICU stay in 461/2138 (22%) TV patients, 236/1493 (16%) NIV patients, and 393/3016 (13%) SV patients (p<0.001).Many different pain assessment methods were used; the EDIN scale was used most frequently (42.3% among those who had at least one pain assessment). We analysed 33,625 patient-days in the TV group to test for associations between pain assessment and the use of opioids, sedatives-hypnotics, or general anaesthetics (O-SH-GA). The rates of pain assessments on patient-days with and without O-SH-GA use were, respectively, 57% vs. 43% while receiving mechanical ventilation, and 60% vs. 34% while not receiving mechanical ventilation (both p<0.001). Multivariable analyses showed that NICU-based guidelines, nursing leadership, and increased surgical admissions promoted the use of routine pain assessments (p<0.001). More pain assessments were performed in newborns below 32-weeks gestational age, those with decreased severity of illness, those already intubated at admission, those requiring mechanical or non-invasive ventilation, or surgery, or use of O-SH-GA.Conclusion: Even though pain is considered the 5th vital sign, only 43% of NICU neonates received bedside pain assessments. Clinical practice variability and low rates of pain assessments in NICUS may reflect weaknesses in the current paradigm used for neonatal pain assessments, their subjectivity, lack of inter-rater reliability, and other long-standing concerns. Results suggest that training to improve the rate of pain assessment in NICUs will enhance pain management in NICUs.Trial Registration: ClinicalTrials.gov #NCT01694745 
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24.
  • Rodil, Iván F., et al. (author)
  • Estimating Respiration Rates and Secondary Production of Macrobenthic Communities Across Coastal Habitats with Contrasting Structural Biodiversity
  • 2020
  • In: Ecosystems (New York. Print). - : Springer Science and Business Media LLC. - 1432-9840 .- 1435-0629. ; 23:3, s. 630-647
  • Journal article (peer-reviewed)abstract
    • A central goal of benthic ecology is to describe the pathways and quantities of energy and material flow in seafloor communities over different spatial and temporal scales. We examined the relative macrobenthic contribution to the seafloor metabolism by estimating respiration and secondary production based on seasonal measurements of macrofauna biomass across key coastal habitats of the Baltic Sea archipelago. Then, we compared the macrofauna estimates with estimates of overall seafloor gross primary production and respiration obtained from the same habitats using the aquatic eddy covariance technique. Estimates of macrobenthic respiration rates suggest habitat-specific macrofauna contribution (%) to the overall seafloor respiration ranked as follows: blue mussel reef (44.5) > seagrass meadow (25.6) > mixed meadow (24.1) > bare sand (17.8) > Fucus-bed (11.1). In terms of secondary production (g C m(-2) y(-1)), our estimates suggest ranking of habitat value as follows: blue mussel reef (493.4) > seagrass meadow (278.5) > Fucus-bed (102.2) > mixed meadow (94.2) > bare sand (52.1). Our results suggest that approximately 12 and 10% of the overall soft-sediment metabolism translated into macrofauna respiration and secondary production, respectively. The hard-bottoms exemplified two end-points of the coastal metabolism, with the Fucus-bed as a high producer and active exporter of organic C (that is, net autotrophy), and the mussel reef as a high consumer and active recycler of organic C (that is, net heterotrophy). Using a combination of metrics of ecosystem functioning, such as respiration rates and secondary production, in combination with direct habitat-scale measurements of O-2 fluxes, our study provides a quantitative assessment of the role of macrofauna for ecosystem functioning across heterogeneous coastal seascapes.
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25.
  • Rodil, Iván F., et al. (author)
  • Towards a sampling design for characterizing habitat-specific benthic biodiversity related to oxygen flux dynamics using Aquatic Eddy Covariance
  • 2019
  • In: PLOS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 14:2
  • Journal article (peer-reviewed)abstract
    • The Aquatic Eddy Covariance (AEC) technique has emerged as an important method to quantify in situ seafloor metabolism over large areas of heterogeneous benthic communities, enabling cross-habitat comparisons of seafloor productivity. However, the lack of a corresponding sampling protocol to perform biodiversity comparisons across habitats is impeding a full assessment of marine ecosystem metabolism. Here, we study a range of coastal benthic habitats, from rocky-bed communities defined by either perennial macroalgae or blue mussel beds to soft-sediment communities comprised of either seagrass, patches of different macrophyte species or bare sand. We estimated that the maximum contribution to the AEC metabolic flux can be found for a seafloor area of approximately 80 m(2) with a 5 meter upstream distance of the instrument across all the habitats. We conducted a sampling approach to characterize and quantify the dominant features of biodiversity (i.e., community biomass) within the main seafloor area of maximum metabolic contribution (i.e., gross primary production and community respiration) measured by the AEC. We documented a high biomass contribution of the macroalgal Fucus vesiculosus, the seagrass Zostera marina and the macroinvertebrate Mytilus edulis to the net ecosystem metabolism of the habitats. We also documented a significant role of the bare sediments for primary productivity compared to vegetated canopies of the soft sediments. The AEC also provided insight into dynamic short-term drivers of productivity such as PAR availability and water flow velocity for the productivity estimate. We regard this study as an important step forward, setting a framework for upcoming research focusing on linking biodiversity metrics and AEC flux measurements across habitats.
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26.
  • Rodil, Iván F., et al. (author)
  • Variable contributions of seafloor communities to ecosystem metabolism across a gradient of habitat-forming species
  • 2021
  • In: Marine Environmental Research. - : Elsevier BV. - 0141-1136 .- 1879-0291. ; 167
  • Journal article (peer-reviewed)abstract
    • The contributions of habitat-forming species to the biodiversity and ecosystem processes of marine and terrestrial ecosystems are widely recognized. Aquatic plants are considered foundation species in shallow ecosystems, as they maintain biodiversity and sustain many ecosystem functions such as primary production and respiration. Despite the increasing amount of biodiversity-ecosystem functioning experiments in seagrass habitats, the effects of benthic variability on ecosystem functioning are rarely investigated across spatially variable aquatic plant habitats. Here, we quantitatively link seasonal variability in seafloor metabolism (i.e. gross primary production and community respiration) with major benthic community components (i.e. microphytobenthos, aquatic plants and macrofauna) across a structural complexity gradient of habitat-forming species (in terms of shoot density and biomass), ranging from bare sand, to a sparse mixture of plants to a dense monospecific seagrass meadow. The increasing complexity gradient enhanced the magnitude of the relationships between benthic community and seafloor metabolism. The daily average seafloor metabolism per season at the bare site was similar to the sparse site, highlighting the role of microphytobenthos for seafloor metabolism in shallow unvegetated sediments. The contribution of the associated macrofauna to the seafloor respiration was similar to the aquatic plant community contribution. Infauna was the main macrofaunal component significantly explaining the seasonal variability of seafloor respiration. However, benthic community-metabolism relationships were stronger within the plant community than within the macrofauna community (i.e. steepest slopes and lowest p-values). Understanding these relationships are a priority since climate change and biodiversity loss are reducing habitat complexity around the world, jeopardizing valuable ecosystem functions and services.
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29.
  • Trubetskaya, Anna, et al. (author)
  • Supercritical extraction and microwave activation of wood wastes for enhanced syngas production and generation of fullerene-like soot particles
  • 2021
  • In: Fuel processing technology. - : Elsevier. - 0378-3820 .- 1873-7188. ; 212
  • Journal article (peer-reviewed)abstract
    • This work demonstrated that supercritical carbon dioxide extraction is effective as a pre-treatment technology to generate soot particles with the fullerene-like structure and increase syngas yield from extracted residues during coupled microwave activation with gasification. Supercritical carbon dioxide extraction removes over half of the fatty and resin acids from needles and branches, whereas the extraction of needles generates greater yields of value-added compounds. The high yields of extractives indicate the effective conversion of waste wood for the sustainable production of value-added chemicals. The wood extraction did not influence the solid residue yields during pyrolysis/gasification emphasizing the significant potential of integrating the extraction process into the holistic biorefinery. Interestingly, supercritical carbon dioxide extraction had a significant effect on the structure and quality of soot particles formed. The differences in the extractives composition led to the formation of needle soot particles with a porous and less ordered nanostructure, whereas the soot branches obtained a ring graphitic structure. The greater yields of steroids and terpenes during the extraction of needles compared to the branches pretreatment indicated the influence of the extractives type on the soot nanostructure. © 2020 The Author(s)
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30.
  • Zhonglai, Li, et al. (author)
  • Copper/Molybdenum Nanocomposite Particles as Catalysts for the Growth of Bamboo-Structured Carbon Nanotubes
  • 2008
  • In: The Journal of Physical Chemistry C. - : American Chemical Society (ACS). - 1932-7447 .- 1932-7455. ; 112:32, s. 12201-12206
  • Journal article (peer-reviewed)abstract
    • Bamboo-structured carbon nanotubes (BCNTs), with mean diameters of 20 nm, have been synthesized on MgO-supported Cu and Mo catalysts by the catalytic chemical vapor deposition of methane. BCNTs could only be generated using a combination of Cu and Mo catalysts. No BCNTs were produced from either individual Cu or Mo catalysts. In combination, Mo was found to be essential for cracking the methane precursor, while Cu was required for BCNT formation. Energy dispersive X-ray analysis of the individual particles at the tips of the nanotubes suggest that Cu and Mo are present as a “composite” nanoparticle catalyst after growth. First-principles modeling has been used to describe the interaction of the Cu/Mo catalyst with the nanotubes, suggesting that the catalyst binds with the same energy as traditional catalysts such as Fe, Ni, and Co.
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