| 1. |
- Rasmusson, Lina M., 1980-
(författare)
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Seagrass Respiration : An assessment of oxygen consumption patterns of temperate marine macrophytes
- 2015
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- In coastal seas, the abundance of marine macrophytes has profound influence on the flows of oxygen and inorganic carbon through the water. Vast amounts of carbon dioxide are taken up by photosynthesis and part of this is respired back into the water column. The photosynthetic carbon uptake of the most common seagrasses of the northern hemisphere is nowadays extensively studied at both community- and individual levels, and its impact on coastal carbon- and oxygen fluxes is quite well defined. However, the coinciding release of carbon dioxide and consumption of oxygen by the processes of mitochondrial respiration and photorespiration in these organisms has as yet not been given much attention, especially concerning how these processes are affected by external factors. For estimations of the rates of mitochondrial respiration, the common approach has been to use values obtained during darkness and treat them as being constant over the day. This approach is questioned in this thesis where the effects of different abiotic and biotic factors on oxygen consumption were examined to elucidate possible variations of seagrass respiration rates (with primary focus on the species Zostera marina), explored mainly using gas exchange techniques. The initial aim was to investigate whether the rates of respiration are at all fluctuating. This was found to be the case. Secondly, impacts of various factors on the respiration process were examined on Z. marina, with additional studies on the seagrass Ruppia maritima and the common green alga Ulva intestinalis. It was found that respiration rates were lower in the light for all three species. Specific investigations on Z. marina showed that respiration rates also varied with time of the day. Moreover, the rates of both respiration and photosynthesis differed between Z. marina shoots of different age as well as among different parts of the leaves. These differences were observed at both ambient (19.1oC) and elevated (29.1oC) temperatures. Photorespiration, previously considered insignificant in seagrasses, was found to have a profound role, as high rates were observed in productive bays, i.e. in settings with low inorganic carbon availability and high oxygen. Overall, this thesis has identified important external and developmental factors influencing the patterns of oxygen consumption and associated carbon dioxide release of two common temperate seagrasses. Clearly, respiration in seagrasses is a dynamic process that responds to a variety of external and developmental factors, which should be carefully considered when assessing the carbon budget of coastal vegetated areas.
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| 2. |
- Asplund, Fredrik, 1977-, et al.
(författare)
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Knowing too much? : On bias due to domain-specific knowledge in internal crowdsourcing for explorative ideas
- 2021
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Ingår i: R&D Management. - : John Wiley & Sons. - 0033-6807 .- 1467-9310.
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Tidskriftsartikel (refereegranskat)abstract
- Internal crowdsourcing utilizes a firm’s employees, of which many have a strong understanding of the domains in which the firm operates, for contributing with, developing and evaluating ideas. On the one hand, these employees can use their domain-specific knowledge to identify the value of what may seem a far-fetched solution to the average employee. On the other hand, previous research has shown that employees typically evaluate ideas in their domains less favorably if they do not align with ongoing exploitation activities. Hence, this study focuses on whether a higher degree of relevant domain-specific knowledge makes employees participating in internal crowdsourcing prefer exploitative solutions when evaluating ideas. An empirical study of an online platform for firm-internal innovation in a multinational engineering company showed that employees who only infrequently participated in internal crowdsourcing mostly contributed to and evaluated ideas within their own domain. Employees who frequently participated also contributed to and evaluated ideas outside their own domains. By statistically analyzing group differences during idea evaluation, we show that employees participating infrequently favor exploitable solutions, whereas employees participating frequently are more uncertain. The former difference is only seen concerning ideas that require domain-specific knowledge to understand, but the latter is observed for all types of ideas. This study makes three substantial contributions. First, employees with domain-specific knowledge, through their preference for exploitative solutions, bias the outcome of internal crowdsourcing when idea evaluation requires domain-specific knowledge. Second, this bias is aggravated by the overall higher level of uncertainty displayed by employees participating frequently in internal crowdsourcing and thereby tend to reach out to other domains. Third, in order to mitigate this, bias management can build engagement in internal crowdsourcing through idea challenges that do not require domain-specific knowledge and consider avoiding employees with a strongly associated domain knowledge for idea evaluation.
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| 3. |
- Asplund, Fredrik, 1977-, et al.
(författare)
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The genesis of public-private innovation ecosystems : Bias and challenges
- 2021
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Ingår i: Technological forecasting & social change. - : Elsevier. - 0040-1625 .- 1873-5509. ; 162
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Tidskriftsartikel (refereegranskat)abstract
- The emergence of technology increasingly depends on innovation ecosystems and frequently involves actors from both industry and academia. However, value creation may experience challenges due to bias formed during public-private innovation ecosystem genesis.This empirical study of bias in a new pan-European public-private initiative provides results regarding innovation ecosystems and the individuals typically active during their genesis: value creation is biased towards the selection of incumbent firms and complement challenges, and participation is biased towards engineers with knowledge of exploitation from multiple domains and researchers with knowledge of exploitation from single domains.This suggests that the implications of the loose coupling emphasised by the innovation ecosystems discourse and the knowledge of the different contexts in which firms capture value are more complex than previously acknowledged. The practical implications are that the ability of public innovation ecosystem leadership to act early on novel technology might be offset by the inability of involved firms to commit to bringing the technology to market and that individuals typically active during public-private innovation ecosystems genesis are not ideal for handling this challenge. In fact, increasingly connected public leadership could smother the innovation ecosystem unless well-connected and multidisciplinary researchers are brought in as brokers.
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| 4. |
- Carr, Herman, 1971-
(författare)
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Energy balance during active carbon uptake and at excess irradiance in three marine macrophytes
- 2005
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The marine environment is an important habitat where many processes occur that affect life conditions on earth. Macrophytes and planktonic oxygen evolvers are an essential component for almost all marine life forms and have developed in an environment that differs largely from the terrestrial habitats. For instance in regards to available ionic forms of inorganic carbon and moving water masses which affects incoming light. It is therefore relevant to examine the physiology of algae and marine plants to identify their unique features and differences to terrestrial plants that once orginated from algae. By using chlorophyll fluorescence measurements alone or combined with measurements of oxygen evolution and protein analysis photosynthetic strategies to withstand excess energy have been evaluated under a variety of experimental conditions. Furthermore metabolic pathways involved in energy transfer from photosynthesis to the site of active carbon uptake have been examined. The following was found:* The ratio between photosynthetic gross oxygen evolution and estimated electron transport rate varies in Ulva spp depending on previous history of light and dark exposures. To obtain P/I curves with ratios close to the theoretical 1:4 value, measurements should be performed on separate pieces of tissue at each irradiance level. * Under carbon deficient conditions, the estimated ETR is larger than the gross oxygen evolution, which may be due to the so called “water-water” cycle and absorption changes in PSII which are not corrected for in the calculation of ETR. * Upon exposure to high irradiances (1500 µmol photons m-2s-1) the PSII core protein D1 is broken down with a concomittant reduction in ETR in Ulva spp. With the decrease in electron transport between PSII and PSI the acidification of the lumen decreases and the ability to dissipate excess energy as heat. At prolonged irradiance, an acclimation occurs with a lesser or no breakdown of D1 indicating an additional photo-protective strategy other than heat dissipation.* Laminaria saccharina is dependent on mitochondrial respiration for active utilization of bicarbonate. By extruding protons outside the plasmalemma an acidification takes place that favors the conversion of bicarbonate into carbon dioxide that then can diffuse in to the cell. These proton pumps are driven by ATP supplied to a large degree from mitochondria, likely through the reductant NADPH produced photochemically. * The marine angiosperm Zostera marina is dependent on mitochondrial respiration for utilization of bicarbonate in a manner similar to that in Laminaria saccharina . However, the water-water cycle may supply additional ATP to the proton pumps in Zostera marina. Both species exhibit a lag-phase at the onset of illumination after a dark incubation period and at least part of this lag-phase is due to a lag in an activation of mitochondrial supported bicarbonate utilization. It is clear that the marine environment holds complex plant and algae species and much is still to discover about the oxygen evolvers that grow beneath the water surface.
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| 5. |
- Di Vincenzo, Faustino, et al.
(författare)
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Attention to ideas! Exploring idea survival in internal crowdsourcing
- 2020
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Ingår i: European Journal of Innovation Management. - : Emerald Group Publishing Ltd.. - 1460-1060 .- 1758-7115.
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Tidskriftsartikel (refereegranskat)abstract
- Purpose: This paper analyzes how the distribution and structure of employees' attention influence idea survival in an organizational internal crowdsourcing session. Design/methodology/approach: Data from an online internal crowdsourcing session carried out within a multinational company with headquarters in Sweden were used to explore how idea attention influenced idea survival. Findings: Our findings indicate that the positive relationship between attention allocation and idea survival is mediated by idea appreciation, i.e. positive comments and suggestions that employees provide in response to ideas. In addition, we find that competition for attention negatively moderates the relationship between idea attention and positive comments. Finally, our results indicate that ideas are more likely to survive if they are submitted earlier in the crowdsourcing process and when the elapsed time since previously posted ideas in the session is longer. Practical implications: This study provides organizers of internal crowdsourcing sessions with new insights about factors influencing idea survival and about potential systematic biases in idea selection due to timing and competition between ideas. Originality/value: This paper contributes to the literature highlighting the relevance of attention-based theory in the context of crowd-based creativity and innovation management.
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| 6. |
- Frishammar, Johan, et al.
(författare)
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Opportunities and challenges in the new innovation landscape : Implications for innovation auditing and innovation management
- 2019
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Ingår i: European Management Journal. - : Elsevier BV. - 0263-2373 .- 1873-5681. ; 37:2, s. 151-164
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Tidskriftsartikel (refereegranskat)abstract
- Innovation auditing is a well-established practice used by managers to identify strengths and weaknesses in innovation. Existing audit frameworks fall short, however, because they neglect three major trends that currently transform the innovation landscape. These trends are as follows: 1) a shift from closed to more open models of innovation ("openness"), 2) a shift from providing physical products to industrial product services ("servitization"), and 3) a shift from an analog to a highly digitalized world ("digitalization"). This article identifies new innovation practices, opportunities, and challenges that arise for manufacturing firms along these trends. The article proposes a revised innovation audit framework, which acknowledges these trends and supports innovation management in increasingly dynamic and competitive environments. (C) 2018 Elsevier Ltd. All rights reserved.
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| 7. |
- George, Rushingisha, 1981-
(författare)
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Seagrasses in warming oceans : physiological and biogeochemical responses
- 2019
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The exponential increase of atmospheric greenhouse gas concentrations over the past 50 years has caused a rise in the global average temperature by more than 1ºC above pre-industrial levels. Ninety-three percent of this heat energy has been absorbed and stored by the oceans, increasing their temperatures, particularly in surface waters. This can produce both negative and positive impacts on the health and function of vital coastal shallow-water communities, hosting seagrasses and macroalgae, which are key primary producers and ecosystem engineers in the coastal zone. The physiological processes of these plants and the biogeochemical processes in associated sediments operate over a wide range of temperatures and their response can serve as early indicators of changes in their ecosystem function. This thesis employed a combination of laboratory, mesocosm and field based experiments to understand: 1) the responses of key physiological processes to elevated temperatures occurring frequently (and likely to occur in a future warming scenario) in seagrass meadows, and how these will affect biogeochemical processes in associated sediments, 2) the exchange of carbon dioxide between seagrass, water and atmosphere, and 3) effects of the tidal variability on biogeochemical processes of tropical seagrass sediments.The results showed that elevated water temperatures cause increased rates of photosynthesis in seagrasses up to a threshold temperature above which rates declines rapidly. The negative effects of temperatures reaching beyond threshold levels increased with repeated days of exposure. The rates of mitochondrial respiration in seagrasses increased with elevated temperatures until a collapse of their respiratory machinery occurred. Photorespiration did not increase linearly with elevated temperatures. The responses of the different components of the seagrass plant (i.e. leaves, shoots, rhizomes and roots) to temperature increase clearly differed, and varied within different parts of each component. Spikes of very high water temperatures, up to 40-44ºC, occur frequently during daytime at low spring tides during the northeast monsoon in the tropical intertidal areas of the western Indian Ocean, and if they occur repeatedly over several days, lead to large biomass loss in seagrasses. Such temperatures also increased methane emission and sulphide levels in seagrass-associated sediments. Submerged macrophytes in shallow coastal waters had pronounced effects on air-water fluxes of carbon dioxide, with an upward flux occurring when partial pressure of carbon dioxide is higher in the seawater than in the air and carbon dioxide escapes the water phase, and a downward flux when carbon dioxide enters the water phase. Plant cover, time of day and tidal level had pronounced consequences on emissions of methane and nitrous oxide as well as sulphide levels in tropical seagrass sediments. Emissions of methane and nitrous oxide positively correlated to sediment organic matter content and the relationship became stronger during high tide.The findings of this thesis indicate that intertidal seagrasses of the tropical WIO region are at special risk of declining under future warming, as they are currently living in an environment where ambient water temperatures frequently reach at, or beyond, threshold levels of key physiological processes during midday hours of low spring tides of the northeast monsoon. The negative effects of high temperature spikes may be further intensified by other anthropogenic stressors (e.g. eutrophication by land-based pollution sources). Taken together, these will reduce seagrass cover and promote the release and emission of historically deposited carbon back to the atmosphere, and this would possibly change these ecosystems from being carbon sinks to being sources and further exacerbate the negative impacts of greenhouse gases.
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| 8. |
- Knudsen, Mette Præst, et al.
(författare)
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Unleashing the Power of Internal Crowds
- 2018
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Konferensbidrag (refereegranskat)abstract
- Much is already known about why and what firms can gain from external crowdsourcing of ideation activities, whereas internal crowdsourcing where firms seek ideas for innovation among its employees has so far received less attention. The rationale for using external and internal crowds has thus been assumed to be the same, to collect a diversity and large number of ideas. This article pinpoints that the design principles known from the external crowdsourcing literature cannot simply be used for internal crowds. In fact, an attempt to do so entails a need for considering several tradeoffs. Drawing on the extant theory and the knowledge that we have accumulated over the years from researching large firm’s use of IT-based ideation systems, we identify these trade-offs, propose several design decisions to consider, which are linked to the innovation ambition of a firm, and develop a model of employee engagement in internal crowdsourcing.
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| 9. |
- Mamboya, Florence Alex, 1971-
(författare)
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Heavy metal contamination and toxicity : Studies of Macroalgae from the Tanzanian Coast
- 2007
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Concentrations of various metals are elevated above background levels in several intertidal areas along the Tanzanian coasts. However, there is little available information concerning the toxicity of these metals and how the uptake of these metals by bioindicators are influenced by external factors, such as heavy rains and increased coastal eutrophication, which tend to fluctuate.The present study focused on the uptake and toxicity of Cu and Zn in two common macroalgal species, Padina gymnospora (Phaeophyta) and Ulva reticulata (Chlorophyta). Laboratory studies were performed where metal content, growth (DGR), maximal quantum yields (Fv/Fm) and protein expression patterns (in Ulva) were measured as a response to exposure to Cu and Zn. The levels of metals accumulated in algal tissues correlated well to exposure concentrations and the longer the exposure time, the greater the uptake. However, an increased nutrient load (tested on Padina) or dilution of the seawater (tested on Ulva) affected both uptake of metals and their toxic effects. Here, DGR was more affected than Fv/Fm, suggesting DGR to be the more sensitive indicator of Cu and Zn toxicity. As shown by 2-D gel electrophoresis, more than ten proteins were up-regulated in U. reticulata after being exposed to Cu (1μg/L), while at higher concentrations (10 and 100 μg/L) of Cu numerous proteins were down-regulated.P. gymnospora was also used as a bioindicator to monitor long-term (1994–2005) and seasonal in-year variations in heavy metal concentrations in the Zanzibar Channel. No clear overall trends were revealed, but analysis of the combined dataset clearly pinpointed the most contaminated sites. It was concluded that seasonal and long-term variations, as well as environmental conditions need to be taken into consideration when using macroalgae as bioindicators.
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| 10. |
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