| 1. |
- Aakko-Saksa, Païvi T., et al.
(författare)
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Renewable Methanol with Ignition Improver Additive for Diesel Engines
- 2020
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Ingår i: Energy and Fuels. - : American Chemical Society (ACS). - 0887-0624 .- 1520-5029.
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Tidskriftsartikel (refereegranskat)abstract
- Reduced emissions and environmental burden from shipping are an important aim of tightening emission regulations and ambitious climate change strategy. Renewable methanol produced from biomass or from other renewable sources represents one option to face these challenges. We studied the potential of renewable methanol to offer such benefits in diesel operation in a Scania ethanol engine, which is designed for additized ethanol fuel (ED95) containing ignition improver and lubricity additives. Methanol (MD95) with several types of ignition improver and lubricity additives was studied for use in diesel engines. MD95 fuels were clean-burning, emitting even less gaseous emissions than ED95, particularly when glycerol ethoxylate was used as an ignition improver. Particle mass and number emissions originating from additives in the experimental fuels could be reduced with an oxidation catalyst. Reduced additive dosing in the MD95 fuels was studied with the aid of fuel injection into the intake manifold. Overall, the results showed that the monofuel MD95 concept is a promising solution for smaller vessels equipped with 800-1200 kW engines. ©
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| 2. |
- Beal, Jacob, et al.
(författare)
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Robust estimation of bacterial cell count from optical density
- 2020
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Ingår i: Communications Biology. - : Springer Science and Business Media LLC. - 2399-3642. ; 3:1
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Tidskriftsartikel (refereegranskat)abstract
- Optical density (OD) is widely used to estimate the density of cells in liquid culture, but cannot be compared between instruments without a standardized calibration protocol and is challenging to relate to actual cell count. We address this with an interlaboratory study comparing three simple, low-cost, and highly accessible OD calibration protocols across 244 laboratories, applied to eight strains of constitutive GFP-expressing E. coli. Based on our results, we recommend calibrating OD to estimated cell count using serial dilution of silica microspheres, which produces highly precise calibration (95.5% of residuals <1.2-fold), is easily assessed for quality control, also assesses instrument effective linear range, and can be combined with fluorescence calibration to obtain units of Molecules of Equivalent Fluorescein (MEFL) per cell, allowing direct comparison and data fusion with flow cytometry measurements: in our study, fluorescence per cell measurements showed only a 1.07-fold mean difference between plate reader and flow cytometry data.
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| 3. |
- Bennett, Joanne M., et al.
(författare)
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Land use and pollinator dependency drives global patterns of pollen limitation in the Anthropocene
- 2020
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Ingår i: Nature Communications. - : Springer Nature. - 2041-1723. ; 11:1
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Tidskriftsartikel (refereegranskat)abstract
- Land use change, by disrupting the co-evolved interactions between plants and their pollinators, could be causing plant reproduction to be limited by pollen supply. Using a phylogenetically controlled meta-analysis on over 2200 experimental studies and more than 1200 wild plants, we ask if land use intensification is causing plant reproduction to be pollen limited at global scales. Here we report that plants reliant on pollinators in urban settings are more pollen limited than similarly pollinator-reliant plants in other landscapes. Plants functionally specialized on bee pollinators are more pollen limited in natural than managed vegetation, but the reverse is true for plants pollinated exclusively by a non-bee functional group or those pollinated by multiple functional groups. Plants ecologically specialized on a single pollinator taxon were extremely pollen limited across land use types. These results suggest that while urbanization intensifies pollen limitation, ecologically and functionally specialized plants are at risk of pollen limitation across land use categories. An insufficient amount of pollen transfer by pollinators (pollen limitation) could reduce plant reproduction in human-impacted landscapes. Here the authors conduct a global meta-analysis and find that pollen limitation is high in urban environments and depends of plant traits such as pollinator dependency.
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| 4. |
- Gonzalez-Aregall, Marta, et al.
(författare)
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Reducing undeclared and misdeclared dangerous goods to improve maritime transport safety
- 2021
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Transport of dangerous goods creates substantial utility to society, but carries a risk to the environment, health and safety. Some of the accidents and incidents occurring during dangerous goods transport can be attributed to poor practices, such as misdeclaration or failure to declare the goods. This pre-study aims to investigate the problem of undeclared and misdeclared dangerous goods transport on container, RoRo and RoPax vessels and to investigate the circumstances and causes that lead to incorrect declaration. For this purpose, this research carried out a literature review and conducted several interviews with main stakeholders in Sweden such as port authorities, port terminals, shipping companies, insurance companies and public institutions. Main results suggest that the existence of different regulations (land transport and sea transport for dangerous goods), can be a risk for managing these goods. Furthermore, it is important to enhance coordination between different actors and increase digitalization to control information flows. This pre-study is coordinated with the longer and larger project Transparent information management and collaboration for improved reliability during transportation of dangerous goods funded by the Swedish Civil Contingencies Agency (MSB).
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| 5. |
- Hulver, Ann Marie, et al.
(författare)
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Interaction effects of crude oil and nutrient exposure on settlement of coral reef benthos
- 2022
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Ingår i: Marine Pollution Bulletin. - : Elsevier BV. - 0025-326X .- 1879-3363. ; 185, part B
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Tidskriftsartikel (refereegranskat)abstract
- Anthropogenic stressors increasingly cause ecosystem-level changes to sensitive marine habitats such as coral reefs. Intensification of coastal development and shipping traffic can increase nutrient and oil pollution on coral reefs, yet these two stressors have not been studied in conjunction. Here, we simulate a disturbance scenario exposing carbonate settlement tiles to nutrient and oil pollution in a full-factorial design with four treatments: control, nutrients, oil, and combination to examine community structure and net primary productivity (NPP) of pioneer communities throughout 28 weeks. Compared to the control treatment oil pollution decreased overall settlement and NPP, while nutrients increased turf algae and NPP. However, the combination of these two stressors resulted in similar community composition and NPP as the control. These results indicate that pioneer communities may experience shifts due to nutrient enrichment, and/or oil pollution. However, the timing and duration of an event will influence recovery trajectories requiring further study.
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| 6. |
- Kanchiralla, Fayas Malik, 1989, et al.
(författare)
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How do variations in ship operation impact the techno-economic feasibility and environmental performance of fossil-free fuels? A life cycle study
- 2023
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Ingår i: Applied Energy. - : Elsevier Ltd. - 1872-9118 .- 0306-2619. ; 350
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Tidskriftsartikel (refereegranskat)abstract
- Identifying an obvious non-fossil fuel solution for all ship types for meeting the greenhouse gas reduction target in shipping is challenging. This paper evaluates the technical viability, environmental impacts, and economic feasibility of different energy carriers for three case vessels of different ship types: a RoPax ferry, a tanker, and a service vessel. The energy carriers examined include battery-electric and three electro-fuels (hydrogen, methanol, and ammonia) which are used in combination with engines and fuel cells. Three methods are used: preliminary ship design feasibility, life cycle assessment, and life cycle costing. The results showed that battery-electric and compressed hydrogen options are not viable for some ships due to insufficient available onboard space for energy storage needed for the vessel's operational range. The global warming reduction potential is shown to depend on the ship type. This reduction potential of assessed options changes also with changes in the carbon intensity of the electricity mix. Life cycle costing results shows that the use of ammonia and methanol in engines has the lowest life cycle cost for all studied case vessels. However, the higher energy conversion losses of these systems make them more vulnerable to fluctuations in the price of electricity. Also, these options have higher environmental impacts on categories like human toxicity, resource use (minerals and metals), and water use. Fuel cells and batteries are not as cost-competitive for the case vessels because of their higher upfront costs and shorter lifetimes. However, these alternatives are less expensive than alternatives with internal combustion engines in the case of higher utilization rates and fuel costs.
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| 7. |
- Malmgren, Elin, 1992, et al.
(författare)
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The HyMethShip Concept: An investigation of system design choices and vessel operation characteristics influence on life cycle performance
- 2020
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Ingår i: Proceedings of 8th Transport Research Arena TRA 2020.
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Konferensbidrag (refereegranskat)abstract
- One potential method to decarbonize the maritime transport sector is by using onboard carbon capture technologies. One such potential future propulsion system is the "HyMethShip - Hydrogen-Methanol Ship propulsion system using onboard pre-combustion carbon capture" concept. In this study we use life cycle assessment to analyse the impact of system design choices on the overall environmental performance of the system. Using the HyMethShip on a vessel is shown to lower climate impact compared to today’s conventional propulsion technologies. The runtime of the carbon capture system and hydrogen leakage are indicated as the main influencers to the environmental performance besides overall system efficiency. The cost of the HyMethShip system is higher than today’s liquid fossil fuel options, but lower than when electro-methanol is used in a conventional engine without applying the HyMethShip concept.
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| 8. |
- Olsson, Tobias, et al.
(författare)
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Life cycle modelling of a wind-powered car carrier - An assessment of cost and greenhouse gas emissions
- 2021
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Konferensbidrag (refereegranskat)abstract
- Possible pathways to reach the International Maritime Organization’s GHG emissions reduction targets for international shipping include selecting zero-carbon or low-carbon fuels or propulsion technologies, reducing the average speed, and reducing fuel consumption. This study investigates the use of wind as a zero-carbon propulsion source for an ocean-going car carrier and compares it to conventional and low-carbon fuel options. Specifically, the study assesses the life cycle climate impact and cost of a car carrier using a fixed sail wind propulsion system and compares it to a car carrier without wind propulsion system using alternative fuels in internal combustion engines. Life cycle assessment and life cycle costing are used, and the study utilizes technical data and cost information from scientific literature and reports. Preliminary performance routing data for the case study vessel is also used. Total GHG emissions as well as annual and total cost of ownership is significantly reduced by using free and abundant wind as the main propulsion energy source on a modern ship specifically designed for wind propulsion. Using a preliminary performance routing in the North Atlantic, the wind-powered car carrier can reduce fuel consumption by 80% compared to a ship without sails using the same hull. Although the addition of a wind propulsion system comes at a higher initial investment cost and increased GHG emissions from construction and scrapping, the reduction in fuel consumption creates significant financial and environmental gains.
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| 9. |
- Oonk, Maaike H. M., et al.
(författare)
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Radiotherapy Versus Inguinofemoral Lymphadenectomy as Treatment for Vulvar Cancer Patients With Micrometastases in the Sentinel Node : Results of GROINSS-V II
- 2021
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Ingår i: Journal of Clinical Oncology. - : Lippincott, Williams & Wilkins. - 0732-183X .- 1527-7755. ; 39:32, s. 3623-3632
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Tidskriftsartikel (refereegranskat)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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| 10. |
- Rodger, James G., et al.
(författare)
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Widespread vulnerability of flowering plant seed production to pollinator declines
- 2021
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Ingår i: Science Advances. - : American Association for the Advancement of Science (AAAS). - 2375-2548. ; 7:42
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Tidskriftsartikel (refereegranskat)abstract
- Despite evidence of pollinator declines from many regions across the globe, the threat this poses to plant populations is not clear because plants can often produce seeds without animal pollinators. Here, we quantify pollinator contribution to seed production by comparing fertility in the presence versus the absence of pollinators for a global dataset of 1174 plant species. We estimate that, without pollinators, a third of flowering plant species would produce no seeds and half would suffer an 80% or more reduction in fertility. Pollinator contribution to plant reproduction is higher in plants with tree growth form, multiple reproductive episodes, more specialized pollination systems, and tropical distributions, making these groups especially vulnerable to reduced service from pollinators. These results suggest that, without mitigating efforts, pollinator declines have the potential to reduce reproduction for most plant species, increasing the risk of population declines.
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