| 69951. |
- Sefidari, H., et al.
(författare)
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The effect of co-firing coal and woody biomass upon the slagging/deposition tendency in iron-ore pelletizing grate-kiln plants
- 2020
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Ingår i: Fuel Processing Technology. ; 199
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Tidskriftsartikel (refereegranskat)abstract
- Woody biomass is being considered a potential co-firing fuel to reduce coal consumption in iron-ore pelletizing rotary kilns. An important consideration is the slagging inside the kiln caused by ash deposition that can lead to process disturbances or shutdowns. In terms of ash chemistry, co-firing woody biomass implies the addition of mainly Ca and K to the Si- and Al-dominated coal-ash (characteristic of high-rank coals) and Fe from the iron-ore that are both inherent to the process. An alkali-laden gaseous atmosphere is also present due to the accumulation of alkali via the recirculation of flue gas in the system. The slagging propensity of blending woody biomass with coal in the grate-kiln process was studied based on the viscosity of the molten phases predicted by global thermochemical equilibrium modeling. This was carried out for variations in temperature, gaseous KOH atmosphere, and fuel blending levels. Results were evaluated and compared using a qualitative slagging indicator previously proposed by the authors where an inverse relationship between deposition tendency and the viscosity of the molten fraction of the ash was established. The results were also compared with a set of co-firing experiments performed in a pilot-scale (0.4 MW) experimental combustion furnace. In general, the co-firing of woody biomass would likely increase the slagging tendency via the increased formation of low-viscosity melts. The fluxing behavior of biomass-ash potentially reduces the viscosity of the Fe-rich aluminosilicate melt and intensifies deposition. However, the results also revealed that there are certain conditions where deposition tendency may decrease via the formation of high-melting-point alkali-containing solid phases (e.g., leucite).
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| 69952. |
- Sefyrin, Johanna, et al.
(författare)
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“But that is a systems solution to me” : Negotiations in IT Design
- 2010
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Ingår i: CoDesign - International Journal of CoCreation in Design and the Arts. - Mortimer House, 37- 41 Mortimer Street, London W1T 3JH, UK : Informa UK Limited. - 1571-0882 .- 1745-3755. ; 6:6, s. 25-41
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Tidskriftsartikel (refereegranskat)abstract
- In this paper we argue that it is not self-evident how 'requirements' are defined, but that 'requirements' are enacted differently by differently situated actors, and that this has consequences in design practices. The purpose of the paper is to explore the consequences of prototyping practices in a local IT design project. The empirical material was gathered through the use of ethnographic methods, and analysed diffractively. Graphical user interface prototypes were tools for formulating business requirements in a business process analysis. Through a reading of a discussion which took place in a work meeting about the prototypes, we discuss how business requirements were enacted. This is discussed in relation to divergent and convergent approaches in IT design. One consequence was a risk that the prototyping process moved too fast to solutions, and another was the risk that the business process analysis method reproduced the dominant story of women's absence in IT design.
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| 69953. |
- Sefyrin, Johanna, et al.
(författare)
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Representational practices in demands driven development of public sector
- 2013
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Ingår i: ELECTRONIC GOVERNMENT (EGOV 2013). - Berlin, Heidelberg : Springer. - 9783642403576 - 9783642403583 ; , s. 200-211
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Konferensbidrag (refereegranskat)abstract
- This paper concerns representational practices in demands driven development of public sector, and the problems they involve. The term demands driven development refers to a movement in public sector towards a closer cooperation with the citizens, primarily with regards to the development of public e-services. The objective with the paper is to explore representational practices through the analysis of practitioners' talk about demands driven development. There are several interrelated problems with representational practices, in this paper analysed through the discussions of practitioners who work with demands driven development of public sector. The conclusion is that these practitioners work with representational practices in a way which they at the same time seem to consider rather problematic.
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| 69954. |
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| 69955. |
- Segawa, Takaya, et al.
(författare)
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Two ABC transport systems carry out peptide uptake in Enterococcus faecalis : Their roles in growth and in uptake of sex pheromones
- 2021
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Ingår i: Molecular Microbiology. - : John Wiley & Sons. - 0950-382X .- 1365-2958. ; 116:2, s. 459-469
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Tidskriftsartikel (refereegranskat)abstract
- Enterococcal pheromone-inducible plasmids encode a predicted OppA-family secreted lipoprotein. In the case of plasmid pCF10, the protein is PrgZ, which enhances the mating response to cCF10 pheromone. OppA proteins generally function with associated OppBCDF ABC transporters to import peptides. In this study, we analyzed the potential interactions of PrgZ with two host-encoded Opp transporters using two pheromone-inducible fluorescent reporter constructs. Based on our results, we propose renaming these loci opp1 (OG1RF_10634-10639) and opp2 (OG1RF_12366-12370). We also examined the ability of the Opp1 and Opp2 systems to mediate import in the absence of PrgZ. Cells expressing PrgZ were able to import pheromone if either opp1 or opp2 was functional, but not if both opp loci were disrupted. In the absence of PrgZ, pheromone import was dependent on a functional opp2 system, including opp2A. Comparative structural analysis of the peptide-binding pockets of PrgZ, Opp1A, Opp2A, and the related Lactococcus lactis OppA protein, suggested that the robust pheromone-binding ability of PrgZ relates to a nearly optimal fit of the hydrophobic peptide, whereas binding ability of Opp2A likely results from a more open, promiscuous peptide-binding pocket similar to L. lactis OppA.
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| 69956. |
- Segebladh, Birgitta, et al.
(författare)
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Allopregnanolone serum concentrations and diurnal cortisol secretion in women with premenstrual dysphoric disorder
- 2013
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Ingår i: Archives of Women's Mental Health. - : Springer Science and Business Media LLC. - 1434-1816 .- 1435-1102. ; 16:2, s. 131-137
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Tidskriftsartikel (refereegranskat)abstract
- Most prior studies in patients with premenstrual dysphoric disorder (PMDD) indicate a blunted hypothalamus-pituitary-adrenal axis function. However, the relationship between neuroactive progesterone metabolites, such as allopregnanolone, and hypothalamus-pituitary-adrenal (HPA) axis function in PMDD patients is relatively sparsely studied. The primary aims of this study were to assess diurnal variation in circulating cortisol and low-dose dexamethasone suppression in PMDD patients and healthy controls, and the relationship between these two HPA axis indices and allopregnanolone serum concentrations. Twenty-six women with prospectively defined PMDD and 30 healthy controls were recruited. Participants underwent diurnal sampling for cortisol serum concentrations and a low-dose dexamethasone suppression test. In addition, morning allopregnanolone serum concentrations were determined. There was no difference in diurnal secretion of cortisol and degree of dexamethasone suppression of cortisol between PMDD patients and healthy controls. However, PMDD patients with high allopregnanolone levels displayed blunted nocturnal cortisol levels in comparison with healthy controls who had low allopregnanolone serum concentrations. In women with PMDD, diurnal secretion of cortisol may be influenced by allopregnanolone levels of the luteal phase. This finding may be attributed to timing of blood sampling in the late luteal phase as well as the individual level of allopregnanolone but could potentially explain the discrepancies in results between studies examining HPA axis function in women with PMDD.
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| 69957. |
- Segebladh, Birgitta, et al.
(författare)
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Evaluation of different add-back estradiol and progesterone treatments to gonadotropin-releasing hormone agonist treatment in patients with premenstrual dysphoric disorder
- 2009
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Ingår i: American Journal of Obstetrics and Gynecology. - : Elsevier BV. - 0002-9378 .- 1097-6868. ; 201:2, s. 139.e1-
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: The aim of this study was to investigate which add-back hormone replacement therapy would be most beneficial in terms of mood effects for patients with premenstrual dysphoric disorder who are receiving gonadotropin-releasing hormone agonist therapy. STUDY DESIGN: Three different add-back hormone replacement treatments were evaluated in a randomized, double-blinded, cross-over clinical trial in 27 patients premenstrual dysphoric disorder. The add-back treatments consisted of 1.5 mg estradiol and 400 mg progesterone, 1.5 mg estradiol and placebo, and 0.5 mg estradiol and 400 mg progesterone. The primary outcome measure was daily symptom ratings for mood and physical symptoms. RESULTS: The highest dose of estradiol in combination with progesterone was associated with the most pronounced symptom recurrence, both in comparison with a lower dose of estradiol together with progesterone and estradiol-only treatment. CONCLUSION: Based on the findings of the present study, long-cycle add-back treatment to avoid frequent progestagen use appears to be most beneficial for patients with premenstrual dysphoric disorder.
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| 69958. |
- Segebladh, Birgitta, et al.
(författare)
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Prevalence of psychiatric disorders and premenstrual dysphoric symptoms in patients with experience of adverse mood during treatment with combined oral contraceptives
- 2009
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Ingår i: Contraception. - : Elsevier BV. - 0010-7824 .- 1879-0518. ; 79:1, s. 50-55
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Negative mood symptoms remain one of the major reasons for discontinuation of combined oral contraceptive pills (COCs). The primary aim of this study was to compare the prevalence of mood and anxiety disorders in women with different experience of COCs. STUDY DESIGN: Thirty women currently on COCs with no report of adverse mood symptoms, 28 women currently on COCs and experiencing mood-related side effects, 33 women who had discontinued COC use due to adverse mood effects and 27 women who had discontinued COC use for reasons other than adverse mood symptoms were included. Ongoing psychiatric disorders were evaluated by a structured psychiatric interview and prevalence rates of premenstrual syndrome (PMS) or premenstrual dysphoric disorder (PMDD) were assessed by daily prospective ratings on the Cyclicity Diagnoser scale. RESULTS: Women with ongoing or past experience of COC-induced adverse mood, more often suffered from mood disorders than women with no reports of adverse mood while on COC. The prevalence of prospectively defined PMS or PMDD did not differ between prior users with positive or negative experience. Women who had discontinued COC use due to adverse mood symptoms more often had had a legal abortion in the past. CONCLUSION: Women with ongoing or past self-reported adverse mood effects from COCs had a significantly increased prevalence of mood disorders.
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| 69959. |
- Segebladh, Birgitta, et al.
(författare)
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Prevalence of violence exposure in women with premenstrual dysphoric disorder in comparison with other gynecological patients and asymptomatic controls
- 2011
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Ingår i: Acta Obstetricia et Gynecologica Scandinavica. - : Wiley. - 0001-6349 .- 1600-0412. ; 90:7, s. 746-752
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Tidskriftsartikel (refereegranskat)abstract
- Objective. The aim of the present study was to estimate prevalence rates of physical,emotional and sexual abuse in women with premenstrual dysphoric disorder(PMDD) in comparison with gynecological outpatients and asymptomatic healthycontrol subjects. Design. Cross-sectional study. Settings. Departments of obstetricsand gynecology in three different Swedish hospitals. Population. Fifty-eightwomen meeting strict criteria for PMDD, a control group of 102 women seekingcare at the gynecological outpatient clinic (ObGyn controls) and 47 asymptomatichealthy control subjects were included in this study. Methods. The Swedish versionof the Abuse Assessment Screen was used to collect information on physical andsexual abuse, and the screening instrument was administered as a face-to-face interview.Main Outcome Measures. Previous and ongoing physical and sexual abuse.Results. Any lifetime abuse (physical, emotional or sexual) was reported by 31.0%of PMDD patients, by 39.2% of ObGyn controls and by 21.3% of healthy controls.The ObGyn controls reported physical and/or emotional abuse significantly moreoften than PMDD patients as well as healthy controls (p<0.05). Lifetime sexualabuse was reported significantly more often by ObGyn controls than by healthycontrols (p<0.05). Conclusions. Patients with PMDD appear not to have sufferedphysical, emotional or sexual abuse to a greater extent than other gynecologicalpatients or healthy control subjects. However, exposure to violence was common inall groups of interviewed women, and for the individual patient these experiencesmay contribute to their experience of symptoms.
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| 69960. |
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