| 301. |
- Vakkilainen, K, et al.
(författare)
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Response of zooplankton to nutrient enrichment and fish in shallow lakes: a pan-European mesocosm experiment
- 2004
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Ingår i: Freshwater Biology. - : Wiley. - 0046-5070 .- 1365-2427. ; 49:12, s. 1619-1632
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Tidskriftsartikel (refereegranskat)abstract
- 1. Responses of zooplankton to nutrient enrichment and fish predation were studied in 1998 and 1999 by carrying out parallel mesocosm experiments in six lakes across Europe. 2. Zooplankton community structure, biomass and responses to nutrient and fish manipulation showed geographical and year-to-year differences. Fish had a greater influence than nutrients in regulating zooplankton biomass and especially the relative abundances of different functional groups of zooplankton. When fish reduced the biomass of large crustaceans, there was a complementary increase in the biomasses of smaller crustacean species and rotifers. 3. High abundance of submerged macrophytes provided refuge for zooplankton against fish predation but this refuge effect differed notably in magnitude among sites. 4. Large crustacean grazers (Daphnia, Diaphanosoma, Sida and Simocephalus) were crucial in controlling algal biomass, while smaller crustacean grazers and rotifers were of minor importance. Large grazers were able to control phytoplankton biomass even under hypereutrophic conditions (up to 1600 mug TP L-1) when grazer biomass was high (>80-90 mug dry mass L-1) or accounted for >30% of the grazer community. 5. The littoral zooplankton community was less resistant to change following nutrient enrichment in southern Spain, at high temperatures (close to 30degreesC), than at lower temperatures (17-23degreesC) characterising the other sites. This lower resistance was because of a greater importance of nutrients than zooplankton in controlling algal biomass. 6. Apart from the reduced role of large crustacean grazers at the lowest latitude, no consistent geographical patterns were observed in the responses of zooplankton communities to nutrient and fish manipulation.
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| 302. |
- Vallo Hult, Helena, 1976-, et al.
(författare)
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Flipped healthcare for better or worse
- 2019
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Ingår i: Health Informatics Journal. - : SAGE Publications. - 1460-4582 .- 1741-2811. ; 25:3, s. 587-597
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Tidskriftsartikel (refereegranskat)abstract
- The medical profession is highly specialized, demanding continuous learning, while also undergoing rapid development in the rise of data-driven healthcare. Based on clinical scenarios, this study explores how resident physicians view their roles and practices in relation to informed patients and patient-centric digital technologies. The paper illustrates how the new role of patients alters physicians’ work and use of data to learn and update their professional practice. It suggests new possibilities for developing collegial competence and using patient experiences more systematically. Drawing on the notion of flipped healthcare, we argue that there is a need for new professional competencies in everyday data work, along with a change in attitudes, newly defined roles, and better ways to identify and develop reliable online sources. Finally, the role of patients, not only as consumers but also producers of healthcare, is a rather formidable and complex cultural change to be addressed. © The Author(s) 2019.
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| 303. |
- Van de Bund, WJ, et al.
(författare)
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Responses of phytoplankton to fish predation and nutrient loading in shallow lakes: a pan-European mesocosm experiment
- 2004
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Ingår i: Freshwater Biology. - : Wiley. - 0046-5070 .- 1365-2427. ; 49:12, s. 1608-1618
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Tidskriftsartikel (refereegranskat)abstract
- 1. The impacts of nutrients (phosphorus and nitrogen) and planktivorous fish on phytoplankton composition and biomass were studied in six shallow, macrophyte-dominated lakes across Europe using mesocosm experiments. 2. Phytoplankton biomass was more influenced by nutrients than by densities of planktivorous fish. Nutrient addition resulted in increased algal biomass at all locations. In some experiments, a decrease was noted at the highest nutrient loadings, corresponding to added concentrations of 1 mg L-1 P and 10 mg L-1 N. 3. Chlorophyll a was a more precise parameter to quantify phytoplankton biomass than algal biovolume, with lower within-treatment variability. 4. Higher densities of planktivorous fish shifted phytoplankton composition toward smaller algae (GALD < 50 mum). High nutrient loadings selected in favour of chlorophytes and cyanobacteria, while biovolumes of diatoms and dinophytes decreased. High temperatures also may increase the contribution of cyanobacteria to total phytoplankton biovolume in shallow lakes.
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| 304. |
- von Rooijen, Marianne, et al.
(författare)
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Rapid activation of haemostasis after hormonal emergency contraception
- 2007
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Ingår i: Thrombosis and Haemostasis. - 0340-6245 .- 2567-689X. ; 97:1, s. 15-20
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Tidskriftsartikel (refereegranskat)abstract
- Hormonal emergency contraception (EC) is a well established contraceptive method, recommended to all women, although the effects on haemostais are not fully evaluated. The aim of this study was to evaluate whether exposure to EC has effects on well established cardiovascular risk factors, and also to examine whether differences exist between two EC treatments. In a prospective randomized cross over design II women used two different EC methods, one with estrogen and levonorgestrel (EE-EC) and one with levonorgestrel only (LNG-EC). Plasma concentrations of haemostatic factors (APC resistance, antithrombin, fibrinogen, prothrombin fragment 1+2, free protein S, factor VII and PAI-I), sex-hormone-binding globulin (SHBG),the apolipoprotein (apo)B/apoAI ratio and C-reactive protein (CRP) were followed frequently during the following 48 hours.
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| 305. |
- Westerdahl, Helena, et al.
(författare)
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Pathogens and Moving Hosts
- 2014
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Ingår i: Animal Movement Across Scales. - 9780199677191
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Bokkapitel (refereegranskat)
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| 306. |
- Wilhelmsen, Lars, 1932, et al.
(författare)
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Factors associated with reaching 90 years of age : a study of men born in 1913 in Gothenburg, Sweden
- 2011
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Ingår i: Journal of Internal Medicine. - : Wiley. - 0954-6820 .- 1365-2796. ; 269:4, s. 441-451
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Tidskriftsartikel (refereegranskat)abstract
- Objectives. Increasing numbers of people reach old age. We wanted to identify variables of importance for reaching 90 years old and determine how the predictive ability of these variables might change over time. Setting and subjects. All men in the city of Gothenburg born in 1913 on dates divisible by 3, which is on the 3rd, 6th, 9th etc., were included in the study. Thus, 973 men were invited, and 855 were examined in 1963 at age 50. Further examinations were made at age 54, 60 and 67. Anthropometric data, lifestyle and parental factors, blood pressure, lung function, X-ray of heart and lungs and maximum work performance were recorded. The area under the receiver operating characteristic curve was used to analyse the predictive capacity of a variable. Results. A total of 111 men (13%) reached 90 years of age, men who reached 90 years were more likely at age 50 to be nonsmokers, consume less coffee, have higher socio-economic status and have low serum cholesterol levels than those who did not reach this age; however, at age 50 or 62, parents' survival was of no prognostic importance. Variables of greatest importance at higher ages were low blood pressure and measures related to good cardiorespiratory function. In multivariable analysis, including all examinations, being a nonsmoker, consuming small amounts of coffee, having high housing costs at age 50, good maximum working capacity and low serum cholesterol were related to a better chance of survival to age 90. Conclusions. Low levels of cardiovascular risk factors, high socio-economic status and good functional capacity, irrespective of parents' survival, characterize men destined to reach the age of 90.
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| 307. |
- Wilken, Susanne, et al.
(författare)
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Primary producers or consumers? : Increasing phytoplankton bacterivory along a gradient of lake warming and browning
- 2018
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Ingår i: Limnology and Oceanography. - : WILEY. - 0024-3590 .- 1939-5590. ; 63:Suppl. 1, s. S142-S155
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Tidskriftsartikel (refereegranskat)abstract
- Eukaryotic phytoplankton form the basis of aquatic food webs and play a key role in the global carbon cycle. Many of these evolutionarily diverse microalgae are also capable of feeding on other microbes, and hence simultaneously act both as primary producers and consumers. The net ecosystem impact of such mixotrophs depends on their nutritional strategy which is likely to alter with environmental change. Many temperate lakes are currently warming at unprecedented rates and are simultaneously increasing in water color (browning) due to increased run-off of humic substances. We hypothesized that the resulting reduction in light intensity and increased bacterial abundances would favor mixotrophic phytoplankton over obligate autotrophs, while higher temperatures might boost their rates of bacterivory. We tested these hypotheses in a mesocosm experiment simulating a gradient of increasing temperature and water color in temperate shallow lakes as expected to occur over the coming century. Mixotrophs showed a faster increase in abundance under the climate change scenario during spring, when they dominated the phytoplankton community. Furthermore, both bacterial abundances and rates of phytoplankton bacterivory increased under future climate conditions. Bacterivory contributed significantly to phytoplankton resource acquisition under future climate conditions, while remaining negligible throughout most of the season in treatments resembling today's conditions. Hence, to our knowledge, we here provide the first evidence for an increasing importance of bacterivory by phytoplankton in future temperate shallow lakes. Such a change in phytoplankton nutritional strategies will likely impact biogeochemical cycles and highlights the need to conceptually integrate mixotrophy into current ecosystem models.
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| 308. |
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| 309. |
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| 310. |
- Xu, Jun, et al.
(författare)
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Contrasting energy pathways at the community level as a consequence of regime shifts
- 2014
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Ingår i: Oecologia. - : Springer Science and Business Media LLC. - 1432-1939 .- 0029-8549. ; 175:1, s. 231-241
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Tidskriftsartikel (refereegranskat)abstract
- Ecological regime shifts typically result in abrupt changes in ecosystem structure through several trophic levels, which leads to rapid ecosystem reconfiguration between regimes. An interesting aspect of the impact of regime shift is that alternative regimes may induce distinct shifts in energy pathways; these have been less tested than structural changes. This paper addresses this by using stable isotopes to establish the energy pathways in fish communities. We specifically focus on the impact of regime shift on changes of the energy pathways, and how the magnitude and direction of these changes affect the local community. We found that energy pathways significantly varied among the planktivorous, benthivorous, and piscivorous trophic guilds as a result of the alternative regimes. The regime shift from a clear to a turbid state altered the food web towards planktonic energy pathways and truncated food chain length, which is indicative of less ecological efficiency. This was confirmed by the adaptive foraging strategies of prevalent omnivores in the current communities. These structural and functional characteristics of trophic interactions might not facilitate classic trophic cascading effects in such a turbid regime and suppress the system's response to environmental changes, e.g., nutrient loading, and restoration efforts in turbid to clear water regime shifts.
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