2,352 research outputs found

    Is organic farming a mitigation option? – A study on N2O emission from winter wheat

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    The objective of the study was to evaluate whether N2O emissions from cropping systems are affected by 1) organic versus conventional farming, 2) proportion of N2-fixing crops in the rotation and 3) use of catch crops

    Estimating š³C and š⁾N turnover rates in the Arctic amphipod Onisimus litoralis: implications for analysing the transfer of sea ice production to under-ice fauna

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    Thesis (M.S.) University of Alaska Fairbanks, 2006The Arctic amphipod Onisimus litoralis migrates from the seafloor to the sea ice to graze on ice algae, a rich food source during the Arctic spring, resulting in complex trophic dynamics. I assessed the effect of temperature and season on the rate of change in stable isotopic composition of amphipods by simulating a diet switch in the laboratory using amphipods collected near Barrow, Alaska in spring and autumn 2004. Additionally, the proportional contributions of food sources to the amphipods' diet in the field were estimated. Isotopic change occurred faster in spring with half-lives of 13.9 (1°C) and 18.7 (4°C) days for carbon and 22.4 days for nitrogen compared to autumn rates of 77 (carbon) and 115 days (nitrogen). Temperature did not have a significant effect on turnover. Change occurred primarily through metabolic turnover (versus growth-related dilution) and was responsible for 84-89% of the change in carbon and 67-77% of the change in nitrogen in both seasons. A two-source mixing model estimated that ice-derived biota contributed 59 (¹17)% to the amphipods' diet in May. These data show that the rate of isotopic change can vary temporally for a single species, highlighting the importance of experimental work for interpreting stable isotope field-data

    The adenomatous polyposis coli protein unambiguously localizes to microtubule plus ends and is involved in establishing parallel arrays of microtubule bundles in highly polarized epithelial cells

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    Loss of full-length adenomatous polyposis coli (APC) protein correlates with the development of colon cancers in familial and sporadic cases. In addition to its role in regulating β-catenin levels in the Wnt signaling pathway, the APC protein is implicated in regulating cytoskeletal organization. APC stabilizes microtubules in vivo and in vitro, and this may play a role in cell migration (Näthke, I.S., C.L. Adams, P. Polakis, J.H. Sellin, and W.J. Nelson. 1996. J. Cell Biol. 134:165–179; Mimori-Kiyosue, Y., N. Shiina, and S. Tsukita. 2000. J. Cell Biol. 148:505–517; Zumbrunn, J., K. Inoshita, A.A. Hyman, and I.S. Näthke. 2001. Curr. Biol. 11:44–49) and in the attachment of microtubules to kinetochores during mitosis (Fodde, R., J. Kuipers, C. Rosenberg, R. Smits, M. Kielman, C. Gaspar, J.H. van Es, C. Breukel, J. Wiegant, R.H. Giles, and H. Clevers. 2001. Nat. Cell Biol. 3:433–438; Kaplan, K.B., A. Burds, J.R. Swedlow, S.S. Bekir, P.K. Sorger, and I.S. Näthke. 2001. Nat. Cell Biol. 3:429–432). The localization of endogenous APC protein is complex: actin- and microtubule-dependent pools of APC have been identified in cultured cells (Näthke et al., 1996; Mimori-Kiyosue et al., 2000; Reinacher-Schick, A., and B.M. Gumbiner. 2001. J. Cell Biol. 152:491–502; Rosin-Arbesfeld, R., G. Ihrke, and M. Bienz. 2001. EMBO J. 20:5929–5939). However, the localization of APC in tissues has not been identified at high resolution. Here, we show that in fully polarized epithelial cells from the inner ear, endogenous APC protein associates with the plus ends of microtubules located at the basal plasma membrane. Consistent with a role for APC in supporting the cytoskeletal organization of epithelial cells in vivo, the number of microtubules is significantly reduced in apico-basal arrays of microtubule bundles isolated from mice heterozygous for APC

    Impaired platelet aggregation and rebalanced hemostasis in patients with chronic hepatitis C virus infection

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    Increased risk of both cardiovascular disease (CVD) and bleeding has been found in patients with chronic hepatitis C (CHC) infection, and a re-balanced hemostasis has been proposed. The aim of this study was to investigate functional whole blood coagulation and platelet function in CHC infection. The prospective study included 82 patients with CHC infection (39 with advanced liver fibrosis and 43 with no or mild liver fibrosis) and 39 healthy controls. A total of 33 patients were treated for CHC infection and achieved sustained virological response (SVR). Baseline and post-treatment blood samples were collected. Hemostasis was assessed by both standard coagulation tests and functional whole blood hemostatic assays (thromboelastograhy (TEG), and platelet aggregation (Multiplate). Patients with CHC and advanced fibrosis had impaired platelet aggregation both compared to patients with no or mild fibrosis and to healthy controls. Patients with CHC and advanced fibrosis also had lower antithrombin, platelet count, and coagulation factors II-VII-X compared to healthy controls. In contrast, TEG did not differ between groups. In treated patients achieving SVR, post-treatment platelet count was higher than pre-treatment counts (p = 0.033) and ADPtest, ASPItest, and RISTOhightest all increased post treatment (all p < 0.05). All Multiplate tests values, however, remained below those in the healthy controls. CHC-infected patients displayed evidence of rebalanced hemostasis with only partly hemostatic normalization in patients achieving SVR. The implications of rebalanced hemostasis and especially the impact on risk of CVD and bleeding warrants further studies

    Systemic family therapy for severe functional disorders in youths. A qualitative study in a psychiatric setting

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    This is the pre-peer reviewed version of the following article: Hulgaard, D.R., Risør, M.B., Lambertsen, G.D. and Rask, C.U. (2021). Systemic family therapy for severe functional disorders in youths: a qualitative study in a psychiatric setting. Journal of Family Therapy, 43, 558-575, which has been published in final form at https://doi.org/10.1111/1467-6427.12319. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions.This study aimed to explore participant experiences of systemic family therapy for youths with functional disorders. After completing family therapy, eight youths and thirteen parents participated in qualitative interviews. The analysis was based on interpretative phenomenological analysis and identified two main themes. The first theme was: ‘Challenges of creating meaning and understanding of child symptoms in family therapy’, with symptom understanding and explanation found to be important, though sometimes challenging, themes in therapy. The second theme was: ‘Clinical encounters in family therapy promote dialogue’, which included the finding that the family therapy setting with joint sessions for family members facilitated in-family communicatio

    Seroprevalence of Borrelia burgdorferi sensu lato and Anaplasma phagocytophilum in Danish horses

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    <p>Abstract</p> <p>Background</p> <p><it>Borrelia burgdorferi </it>sensu lato and <it>Anaplasma phagocytophilum </it>are able to infect horses. However, the extend to which Danish horses are infected and seroconvert due to these two bacteria is unknown. The aim of the present study was to evaluate the seroprevalence of <it>B. burgdorferi </it>sensu lato and <it>A. phagocytophilum </it>in Danish horses.</p> <p>Methods</p> <p>A total of 390 blood samples collected from all major regions of Denmark and with a geographical distribution corresponding to the density of the Danish horse population were analyzed. All samples were examined for the presence of antibodies against <it>B. burgdorferi </it>sensu lato and <it>A. phagocytophilum </it>by the use of the SNAP<sup>ÂŽ</sup>4DX <sup>ÂŽ </sup>ELISA test.</p> <p>Results</p> <p>Overall, 29.0% of the horses were seropositive for <it>B. burgdorferi </it>sensu lato whereas 22.3% were seropositive for <it>A. phagocytophilum</it>.</p> <p>Conclusions</p> <p>Antibodies against <it>B burgdorferi </it>sensu lato and <it>A. phagocytophilum </it>are commonly found among Danish horses thus showing that Danish horses are frequently infected by these organisms.</p

    Metabolomic phenotyping of a cloned pig model

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    <p>Abstract</p> <p>Background</p> <p>Pigs are widely used as models for human physiological changes in intervention studies, because of the close resemblance between human and porcine physiology and the high degree of experimental control when using an animal model. Cloned animals have, in principle, identical genotypes and possibly also phenotypes and this offer an extra level of experimental control which could possibly make them a desirable tool for intervention studies. Therefore, in the present study, we address how phenotype and phenotypic variation is affected by cloning, through comparison of cloned pigs and normal outbred pigs.</p> <p>Results</p> <p>The metabolic phenotype of cloned pigs (n = 5) was for the first time elucidated by nuclear magnetic resonance (NMR)-based metabolomic analysis of multiple bio-fluids including plasma, bile and urine. The metabolic phenotype of the cloned pigs was compared with normal outbred pigs (n = 6) by multivariate data analysis, which revealed differences in the metabolic phenotypes. Plasma lactate was higher for cloned vs control pigs, while multiple metabolites were altered in the bile. However a lower inter-individual variability for cloned pigs compared with control pigs could not be established.</p> <p>Conclusions</p> <p>From the present study we conclude that cloned and normal outbred pigs are phenotypically different. However, it cannot be concluded that the use of cloned animals will reduce the inter-individual variation in intervention studies, though this is based on a limited number of animals.</p

    Impact of cracks on distribution of chloride-induced reinforcement corrosion

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    Surface crack width is regulated in codes to limit corrosion of reinforcement bars in concrete. However, the influence of surface crack width on corrosion damages is not directly inferable from previous research.In this work, data on corroded cracked concrete specimens in chloride environments was compiled. Detailed information was included, such as crack and pit locations, local corrosion pattern, etc. Five hypotheses on the influence of transversal cracks on corrosion damage were formulated, and statistical methods were used to test them on the dataset.Transversal cracks were good indicators of the position of corrosion pits. The corrosion rate of the pit increased in proximity of a crack. With time, pits grew in depth at a slower rate but increased in number. No clear correlation between surface crack width and corrosion damage was found. Results point out discrepancies in the collected data, arguing for the need of well-defined procedures for assessing crack and corrosion damage.Further, the statistical treatment allowed for identification of bias in existing data, which was used as a research planning tool to provide guidance on the design of additional experiments. Thus, recommendations for future experimental work required to reduce the bias are given
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