73 research outputs found

    Diet and lifestyle of the Sami of southern Lapland in the 1930s-1950s and today

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    To describe the lifestyle of the Sami of southern Lapland 50 to 70 years ago in relation to the present-day Sami and non-Sami populations and, thereby, to provide a basis for future studies of culturally related determinants of health and illness. A qualitative analysis, and a quantitative comparison of Sami and non-Sami groups. Semi-structured interviews were conducted with 20 elderly Sami concerning their parents’ lifestyle and diet 50 to 70 years ago. Questionnaire data from 81 reindeer-herding Sami, 226 non-reindeer-herding Sami and 1,842 sex-, age- and geographically matched non-Sami from the population-based VĂ€sterbotten Intervention Project were analysed by non-parametric tests and partial least squares methodology. Surprisingly, fatty fish may have been more important than reindeer meat for the Sami of southern Lapland in the 1930s to 1950s, and it is still consumed more frequently by reindeer-herding Sami than nonreindeer-herding Sami and non-Sami. Other dietary characteristics of the historical Sami and present-day reindeer-herding Sami were higher intakes of fat, blood and boiled coffee, and lower intakes of bread, fibre and cultivated vegetables, compared with present-day non-Sami. Physical activity was also a part of the daily life of the Sami to a greater extent in the 1930s to 1950s than today. Sami men often worked far from home, while the women were responsible for fishing, farming, gardening (which was introduced in the 1930–1950 period), as well as housework and childcare. For studies investigating characteristic lifestyle elements of specific ethnic groups, the elements of greatest acknowledged cultural importance today (in this case reindeer meat) may not be of the most objective importance traditionally

    Age distributions of Greenlandic dwarf shrubs support concept of negligible actuarial senescence

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    Many plants and sessile animals may not show actuarial senescence, the increase in mortality with age predicted to be ubiquitous by classic evolutionary theories of aging. Age-structured demographic information is, however, limited for most organisms. We assessed the age distributions of nine dwarf shrub species from 863 taproot samples collected in coastal east Greenland. Penalized composite link models (pclm) were used to fill gaps in the observed age ranges, caused by low species-specific sample sizes in relation to life span. Resulting distributions indicate that mortality patterns are independent of age. Actuarial senescence is thus negligible in these dwarf shrub populations. We suggest that smoothing techniques such as pclm enable consideration of noisy age data for determining age distributions. These distributions may, in turn, reveal age effects on demographic rates. Moreover, age determination from the root collars of small plants constitutes a powerful technique to further investigate age dependency of the demography of many plant species, including eudicot herbs. Using these methods for long-lived plants where long-term monitoring is unrealistic, we show that age is unlikely to be an important variable for making population projections and determining extinction risks

    Life after hip fracture - Impact of home rehabilitation versus conventional care and patients' experiences of the recovery process in a short- and long-term perspective

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    Aim In a short- and long-term perspective compare a geriatric home rehabilitation programme (HR) for patients with hip fracture with conventional care (CC), and to capture the patients experience of the consequences of the injury and their conceptions of what influences the recovery process. Method The thesis is based on two quantitative and two qualitative studies. The two quantitative studies were randomized and controlled, longitudinal intervention studies in which 102 community-dwelling elderly patients who had received either HR (n = 48) or CC (n = 54) were followed for one year after discharge. The HR programme, which started immediately after admission to hospital, included active participation from patients in setting goals and planning discharge. The programme was focused on encouraging the participants’ self-efficacy and exercising daily activities. Assessment of balance confidence, degree of independence and frequency of daily activities, health-related quality of life, mood, perceived recovery, and basic physical performance were made one month, six months and one year after hospital discharge. In the qualitative, phenomenographic studies 18 patients were interviewed one month and one year after discharge about how they experienced the consequences of the hip fracture and their conceptions of the recovery process. Results The main recovery for all participants took place during the first six months after discharge. The results show that those who had participated in the HR programme recovered faster than those who hade received CC. Additionally, in a longer perspective they were more confident and independent than the CC group, although the differences between the groups had diminished at one year. Only 14 persons in the HR group and five persons in the CC group considered themselves fully recovered after one year. The results from the interviews showed that the hip fracture caused social and existential cracks in the individuals’ lives. The hip fracture came unexpectedly and resulted in an experience of a changed body and a more restricted life. The interviewees experienced that they had increased difficulties to move and to manage independently. One reaction was that their pre-fracture self-view as being healthy and stable had been punctured by the injury. Although positive experiences, such as being satisfied with the recovery, were also expressed, many of the negative consequences remained or had even deepened one year after discharge. A dominating experience was that they were more cautious, afraid of further falls, and felt more sedentary and isolated than before the fracture. Conclusions The results show that the negative consequences of a hip fracture are substantial and long-lasting. However, the HR programme had a more significant impact than CC on the participants’ functioning and confidence, which was most evident in the early phase of the recovery. An essential task for health care should be to create continued possibilities for rehabilitation after discharge from hospital also in a longer perspective, and not primarily focus on the medical and physical needs. The patients’ experiences and psychological reactions that may follow a hip fracture should also be considered

    Establishing a library of resources to help people understand key concepts in assessing treatment claims—The “Critical thinking and Appraisal Resource Library” (CARL)

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    Background People are frequently confronted with untrustworthy claims about the effects of treatments. Uncritical acceptance of these claims can lead to poor, and sometimes dangerous, treatment decisions, and wasted time and money. Resources to help people learn to think critically about treatment claims are scarce, and they are widely scattered. Furthermore, very few learning-resources have been assessed to see if they improve knowledge and behavior. Objectives Our objectives were to develop the Critical thinking and Appraisal Resource Library (CARL). This library was to be in the form of a database containing learning resources for those who are responsible for encouraging critical thinking about treatment claims, and was to be made available online. We wished to include resources for groups we identified as ‘intermediaries’ of knowledge, i.e. teachers of schoolchildren, undergraduates and graduates, for example those teaching evidence-based medicine, or those communicating treatment claims to the public. In selecting resources, we wished to draw particular attention to those resources that had been formally evaluated, for example, by the creators of the resource or independent research groups. Methods CARL was populated with learning-resources identified from a variety of sources—two previously developed but unmaintained inventories; systematic reviews of learning-interventions; online and database searches; and recommendations by members of the project group and its advisors. The learning-resources in CARL were organised by ‘Key Concepts’ needed to judge the trustworthiness of treatment claims, and were made available online by the James Lind Initiative in Testing Treatments interactive (TTi) English (www.testingtreatments.org/category/learning-resources).TTi English also incorporated the database of Key Concepts and the Claim Evaluation Tools developed through the Informed Healthcare Choices (IHC) project (informedhealthchoices.org). Results We have created a database of resources called CARL, which currently contains over 500 open-access learning-resources in a variety of formats: text, audio, video, webpages, cartoons, and lesson materials. These are aimed primarily at ‘Intermediaries’, that is, ‘teachers’, ‘communicators’, ‘advisors’, ‘researchers’, as well as for independent ‘learners’. The resources included in CARL are currently accessible at www.testingtreatments.org/category/learning-resources Conclusions We hope that ready access to CARL will help to promote the critical thinking about treatment claims, needed to help improve healthcare choices

    Hyperestrogenism Affects Adult Height Outcome in Growth Hormone Treated Boys With Silver-Russell Syndrome

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    Background: Intrauterine growth retardation and short stature are common features in Silver-Russell syndrome (SRS). Despite recombinant growth hormone (rGH) treatment, poor pubertal height gain, affecting adult height (AH), is common. This study investigated whether growth patterns and estrogen concentrations are associated with AH outcome in rGH treated SRS males.Methods: In this retrospective longitudinal single-center study, 11 males with SRS were classified as non-responders (NR = 6) or responders (R = 5), depending on AH adjusted for midparental height. Epigenetic analysis and longitudinal growth measures, including bone age, rGH related parameters, pubertal development, gonadotropins and estrogen concentrations, were analyzed until AH.Results: Pubarche before 9 years was only observed in one NR. At 10 years of age, there was no difference in gonadotropins between NR and R. However, estradiol (E2) concentrations at 10 years of age showed a strong association to AH adjusted for MPH (r = −0.78, p < 0.001). Serum E2 (pmol/L) was significantly higher in NR at ages 10 years [median (range) 2 (<2–5) vs. <2 (<2)], 12 years [23 (10–57) vs. 2 (<2–2)] and 14 years [77 (54–87) vs. 24 (<2–38)] but not at 16 years. Birth weight standard deviation score (SDS) was lower in NR [−4.1 (−4.7 to −2.1) vs. −2.7 (−3.3 to −1.7)]. Weight gain (SDS) until pubertal onset was greater in NR [2.4 (1.4–3.5) vs. 0.8 (−0.4 to 1.7)] and pubertal height gain (SDS) was lower in NR [−1.0 (−2.7–0.4) vs. 0.1 (−0.1 to 1.1)]. At AH, a number of NR and R had high E2 concentrations and small testes.Conclusion: Increased E2 concentrations at age 10, 12, and 14 years were associated to less pubertal height gain, thus affecting AH. Due to the small number of patients, the results need to be confirmed in larger cohorts. The finding of impaired testicular development stresses the need of hormonal evaluation as a complement to clinical and radiological assessment when predicting AH in males with SRS

    Treatment of Spent Pickling Acid from Stainless Steel Production : A review of regeneration technologies with focus on the neutralisation process for implementation in Chinese industry

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    Pickling is a unit operation within stainless steel production, which means treating the steel with hydrofluoric acid (HF) and nitric acid (HNO3), also called mixed acid. The whole process generates waste water streams which have to be treated before released to recipient. The aim of this degree thesis was to make an evaluation of different possibilities for reduction of emissions from the pickling process with China as a possible future market. The work consisted of two different parts; the first was to describe and evaluate different treatment methods for waste pickling acid, with emphasis on denitrification technologies. The second and main part was to make a fundamental description of the neutralisation process and outline important parameters. The work was performed by gathering information from literature but also from industry in both Sweden and China. The work has been a collaboration between the Royal Institute of Technology (KTH), the Swedish Environmental Institute (IVL) and the company Scanacon. A review of the different acid recovery methods; ionic exchange, diffusion dialysis and extraction was made. The study showed that ionic exchange is a robust method with relatively low cost and therefore it has been largely implemented both in Swedish and Chinese industry. The outflow however still requires neutralisation. Nitrate reduction can be performed as “end of pipe”, those methods investigated in this study were; biological treatment, reverse osmosis and nanofiltration. Meanwhile, internal solutions such as evaporation and electro-dialysis are two interesting technologies which reduce nitrates in combination with acid recovery. It was found that slaked lime (Ca(OH)2) is the most suitable neutralisation agent for pickling waste and, besides the choice of chemicals, many important parameters influence the process, such as the optimal pH, mixing and conditions during lime slaking. Based on information from one of the visited sites in Sweden a mass balance of the neutralisation facility was made and from that the required amount of Ca(OH)2 was calculated. The calculations were verified by an experimental part performed by IVL, using pickling acids from the same site. The amount of metals in the outgoing water was calculated using software “Medusa” but also by equilibrium equations. However, the results differed somewhat; this is probably due to the fact that Medusa takes other complexes and their interaction, besides the formed metal hydroxides, into consideration. Within the mining industry research has been made on different methods for neutralisation and some have been tested in field. An example is the High Density Sludge process (HDS), were an amount of sludge is recycled back to the neutralisation tank. It was shown that this gave improved sludge properties and decreased lime consumption. This could perhaps also be implemented for waste water in the stainless steel industry, and the method was also tested during the experimental part of this project. The dry content increased after a number of cycles but further investigation is required before any conclusion can be drawn.Betning Ă€r en enhetsprocess inom tillverkningen av rostfritt stĂ„l dĂ„ godset behandlas med fluorvĂ€te syra (HF) och salpetersyra (HNO3), ocksĂ„ kallad blandsyra. Betningen ger upphov till vatten strömmar som mĂ„ste behandlas innan de slĂ€pps ut till recipienten. Syftet med det hĂ€r examensarbetet var att göra en utvĂ€rdering av olika tekniker för att reducera utslĂ€pp till vatten frĂ„n betningen med Kina som potentiell framtida marknad. Arbetet bestod av tvĂ„ delar; den första delen var att beskriva och utvĂ€rdera olika behandlingsmetoder av förbrukade betbad med betoning pĂ„ denitrifikationstekniker. Den andra och största delen var att göra en grundlĂ€ggande beskrivning av neutralisationsprocessen. Studien utfördes genom att inhĂ€mta information frĂ„n litteratur samt frĂ„n industrin i bĂ„de Sverige och Kina. Arbetet har varit ett samarbetsprojekt mellan Kungliga Tekniska Högskolan (KTH), Svenska miljöinstitutet (IVL) och företaget Scanacon.    Arbetet behandlar syraĂ„tervinningsystemen; jonbytare, diffusions dialys samt extraktion. Nitrat reduktion kan ske internt eller externt dĂ€r de externa Ă„tgĂ€rder som behandlas i denna rapport Ă€r biologisk rening, omvĂ€nd osmos och nanofiltrering. De interna metoderna avdunstning och elektrodialys Ă€r intressanta eftersom de Ă„tervinner syran samtidigt som de reducerar nitraterna avsevĂ€rt. Studien visade att jonbyte, pĂ„ grund av dess robusthet och relativt lĂ„ga kostnad Ă€r den mest implementerade metoden för syraĂ„tervinning i bĂ„de svensk och kinesisk industri idag. Restprodukten frĂ„n jonbytaren krĂ€ver dock fortsatt behandling, dĂ€r det traditionella valet Ă€r neutralisation. Studien visade att slĂ€ckt kalk (Ca(OH)2) Ă€r det mest passande kemikalien för neutralisation av betsyror. Förutom kemikalieval sĂ„ finns det mĂ„nga parametrar som pĂ„verkar effektiviteten hos processen sĂ„ som pH, omrörning och förhĂ„llanden under kalkslĂ€ckningen. Baserat pĂ„ information ifrĂ„n ett av de besökta stĂ„lverken i Sverige, gjordes en massbalans över dess neutralisationanlĂ€ggning. UtifrĂ„n de flöden som denna gav kunde den teoretiska mĂ€ngden kalk som krĂ€vdes för utfĂ€llning rĂ€knas ut. BerĂ€kningarna verifierades med en experimentell del som utfördes av IVL pĂ„ betsyror frĂ„n samma verk. Resthalterna av metall i utgĂ„ende vatten berĂ€knades med programmet ”Medusa” men ocksĂ„ med jĂ€mviktsekvationer. Resultaten mellan de tvĂ„ skiljde sig, detta beror förmodligen pĂ„ att Medusa förutom hydroxidutfĂ€llning tar hĂ€nsyn till andra utfĂ€llningskomplex och dess interaktioner. Inom gruvvatten industrin har det forskats en del kring olika neutralisationsmetoder, en i litteraturen föreslagen sĂ„dan Ă€r ”High Density Sludge process (HDS)”. HĂ€r Ă„terförs en del av slammet tillbaka till neutralisationssteget, vilket visade sig ge förbĂ€ttrade slamegenskaper och minskad kalkĂ„tgĂ„ng. Det var intressant att undersöka om denna metod ocksĂ„ gick att implementera pĂ„ förbrukade betbad och dĂ€rför prövades metoden i den experimentella delen av detta projekt. Detta gav efter ett antal Ă„terföringscykler högre torrhalt pĂ„ slammet, dock krĂ€vs fortsatta undersökningar innan nĂ„gon slutsats kan dras

    Treatment of Spent Pickling Acid from Stainless Steel Production : A review of regeneration technologies with focus on the neutralisation process for implementation in Chinese industry

    No full text
    Pickling is a unit operation within stainless steel production, which means treating the steel with hydrofluoric acid (HF) and nitric acid (HNO3), also called mixed acid. The whole process generates waste water streams which have to be treated before released to recipient. The aim of this degree thesis was to make an evaluation of different possibilities for reduction of emissions from the pickling process with China as a possible future market. The work consisted of two different parts; the first was to describe and evaluate different treatment methods for waste pickling acid, with emphasis on denitrification technologies. The second and main part was to make a fundamental description of the neutralisation process and outline important parameters. The work was performed by gathering information from literature but also from industry in both Sweden and China. The work has been a collaboration between the Royal Institute of Technology (KTH), the Swedish Environmental Institute (IVL) and the company Scanacon. A review of the different acid recovery methods; ionic exchange, diffusion dialysis and extraction was made. The study showed that ionic exchange is a robust method with relatively low cost and therefore it has been largely implemented both in Swedish and Chinese industry. The outflow however still requires neutralisation. Nitrate reduction can be performed as “end of pipe”, those methods investigated in this study were; biological treatment, reverse osmosis and nanofiltration. Meanwhile, internal solutions such as evaporation and electro-dialysis are two interesting technologies which reduce nitrates in combination with acid recovery. It was found that slaked lime (Ca(OH)2) is the most suitable neutralisation agent for pickling waste and, besides the choice of chemicals, many important parameters influence the process, such as the optimal pH, mixing and conditions during lime slaking. Based on information from one of the visited sites in Sweden a mass balance of the neutralisation facility was made and from that the required amount of Ca(OH)2 was calculated. The calculations were verified by an experimental part performed by IVL, using pickling acids from the same site. The amount of metals in the outgoing water was calculated using software “Medusa” but also by equilibrium equations. However, the results differed somewhat; this is probably due to the fact that Medusa takes other complexes and their interaction, besides the formed metal hydroxides, into consideration. Within the mining industry research has been made on different methods for neutralisation and some have been tested in field. An example is the High Density Sludge process (HDS), were an amount of sludge is recycled back to the neutralisation tank. It was shown that this gave improved sludge properties and decreased lime consumption. This could perhaps also be implemented for waste water in the stainless steel industry, and the method was also tested during the experimental part of this project. The dry content increased after a number of cycles but further investigation is required before any conclusion can be drawn.Betning Ă€r en enhetsprocess inom tillverkningen av rostfritt stĂ„l dĂ„ godset behandlas med fluorvĂ€te syra (HF) och salpetersyra (HNO3), ocksĂ„ kallad blandsyra. Betningen ger upphov till vatten strömmar som mĂ„ste behandlas innan de slĂ€pps ut till recipienten. Syftet med det hĂ€r examensarbetet var att göra en utvĂ€rdering av olika tekniker för att reducera utslĂ€pp till vatten frĂ„n betningen med Kina som potentiell framtida marknad. Arbetet bestod av tvĂ„ delar; den första delen var att beskriva och utvĂ€rdera olika behandlingsmetoder av förbrukade betbad med betoning pĂ„ denitrifikationstekniker. Den andra och största delen var att göra en grundlĂ€ggande beskrivning av neutralisationsprocessen. Studien utfördes genom att inhĂ€mta information frĂ„n litteratur samt frĂ„n industrin i bĂ„de Sverige och Kina. Arbetet har varit ett samarbetsprojekt mellan Kungliga Tekniska Högskolan (KTH), Svenska miljöinstitutet (IVL) och företaget Scanacon.    Arbetet behandlar syraĂ„tervinningsystemen; jonbytare, diffusions dialys samt extraktion. Nitrat reduktion kan ske internt eller externt dĂ€r de externa Ă„tgĂ€rder som behandlas i denna rapport Ă€r biologisk rening, omvĂ€nd osmos och nanofiltrering. De interna metoderna avdunstning och elektrodialys Ă€r intressanta eftersom de Ă„tervinner syran samtidigt som de reducerar nitraterna avsevĂ€rt. Studien visade att jonbyte, pĂ„ grund av dess robusthet och relativt lĂ„ga kostnad Ă€r den mest implementerade metoden för syraĂ„tervinning i bĂ„de svensk och kinesisk industri idag. Restprodukten frĂ„n jonbytaren krĂ€ver dock fortsatt behandling, dĂ€r det traditionella valet Ă€r neutralisation. Studien visade att slĂ€ckt kalk (Ca(OH)2) Ă€r det mest passande kemikalien för neutralisation av betsyror. Förutom kemikalieval sĂ„ finns det mĂ„nga parametrar som pĂ„verkar effektiviteten hos processen sĂ„ som pH, omrörning och förhĂ„llanden under kalkslĂ€ckningen. Baserat pĂ„ information ifrĂ„n ett av de besökta stĂ„lverken i Sverige, gjordes en massbalans över dess neutralisationanlĂ€ggning. UtifrĂ„n de flöden som denna gav kunde den teoretiska mĂ€ngden kalk som krĂ€vdes för utfĂ€llning rĂ€knas ut. BerĂ€kningarna verifierades med en experimentell del som utfördes av IVL pĂ„ betsyror frĂ„n samma verk. Resthalterna av metall i utgĂ„ende vatten berĂ€knades med programmet ”Medusa” men ocksĂ„ med jĂ€mviktsekvationer. Resultaten mellan de tvĂ„ skiljde sig, detta beror förmodligen pĂ„ att Medusa förutom hydroxidutfĂ€llning tar hĂ€nsyn till andra utfĂ€llningskomplex och dess interaktioner. Inom gruvvatten industrin har det forskats en del kring olika neutralisationsmetoder, en i litteraturen föreslagen sĂ„dan Ă€r ”High Density Sludge process (HDS)”. HĂ€r Ă„terförs en del av slammet tillbaka till neutralisationssteget, vilket visade sig ge förbĂ€ttrade slamegenskaper och minskad kalkĂ„tgĂ„ng. Det var intressant att undersöka om denna metod ocksĂ„ gick att implementera pĂ„ förbrukade betbad och dĂ€rför prövades metoden i den experimentella delen av detta projekt. Detta gav efter ett antal Ă„terföringscykler högre torrhalt pĂ„ slammet, dock krĂ€vs fortsatta undersökningar innan nĂ„gon slutsats kan dras

    Vilhelmina & MRF Assistance : mötet mellan ungdomar i glesbygd och ett modernt tjÀnsteföretag speglat i en klassisk tankefigur

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    In focus for this thesis is a village in a sparsely populated area in the county of VÀsterbotten, Vil­helmina, and its encounter with a relatively large, unusual, and modern company within the service sector, MRF Assistance, that established itself in Vilhelmina. This event is interesting because it implies the encroachment of "the informati on-age" on the local labour market of Vilhelmina. Previous negative experiences made many citizens sceptical to the establishment, while others saw it as a solution. The theoretical point of departure in illuminating this encounter is Ferdinand Tönnies' classical concepts "Gemeinschaft und Gesellschaft", and their role when people make decisions and evaluate and reflect upon different perceived choices in their lives. I will describe this encounter from the perspective of the youths who were employed by the company. The aim of the study is to illuminate the modernisation processes in sparsely populated areas. More spe­cifically the research questions are as follows: How do the informants perceive their lives and an­choring in Vilhelmina ("Gemeinschaft")? How do they perceive the establishment of MRF As­sistance ("Gesellschaft")? What are the experiences of the employees regarding the time they were employed by the company, was it possible to combine "Gemeinschaft" and "Ge­sellschaft"? Different methods have been used in this thesis in order to triangulate the information and re­ach valid results. Most obvious is the combination of quantitative and qualitative methods. The data used in the quantitative part of the investigation have been collected from a survey administe­red to the employees of the company. The qualitative part is based on qualitative interviews with employees on different occasions. The qualitative interpretations have applied the grounded theo­ry - approach. The discoveries, which were generated with help of codes and categories, were than discussed in relation to relevant research and especially to the theoretical points of departure. Some of the tracers identified as empirically grounded and possible to integrate in a comparative analysis were the following: The norm-system of the company sometimes proved to be in conflict with the one of the village. In spite of this, it proved to be easy for the young employees to deal with the situation. The ambivalence was there but they were able to handle it. The young employ­ees showed trust and confidence in the company as a modern component of their society. Feelings of reliance on what was new were possible to combine with feelings of confidence in the habitual. They could easily live with ambivalence. Their cognitive maps were flexible and more context dependent than rigid. The young employees, in evaluating options and reflecting upon conse­quences of decisions, tend to activate the social representations of "Gemeinschaft" and "Gemein­schaft". The classic ideal-type proved still to be in use. A final remark is that taken together, the results and interpretations indicate at least hypothetically, that young people in rural areas rise to the standards that companies like MRF Assistance demand from its employees. The apprehension of potential contractors seems to be based more on myths than on reality.digitalisering@um

    Treatment of Spent Pickling Acid from Stainless Steel Production : A review of regeneration technologies with focus on the neutralisation process for implementation in Chinese industry

    No full text
    Pickling is a unit operation within stainless steel production, which means treating the steel with hydrofluoric acid (HF) and nitric acid (HNO3), also called mixed acid. The whole process generates waste water streams which have to be treated before released to recipient. The aim of this degree thesis was to make an evaluation of different possibilities for reduction of emissions from the pickling process with China as a possible future market. The work consisted of two different parts; the first was to describe and evaluate different treatment methods for waste pickling acid, with emphasis on denitrification technologies. The second and main part was to make a fundamental description of the neutralisation process and outline important parameters. The work was performed by gathering information from literature but also from industry in both Sweden and China. The work has been a collaboration between the Royal Institute of Technology (KTH), the Swedish Environmental Institute (IVL) and the company Scanacon. A review of the different acid recovery methods; ionic exchange, diffusion dialysis and extraction was made. The study showed that ionic exchange is a robust method with relatively low cost and therefore it has been largely implemented both in Swedish and Chinese industry. The outflow however still requires neutralisation. Nitrate reduction can be performed as “end of pipe”, those methods investigated in this study were; biological treatment, reverse osmosis and nanofiltration. Meanwhile, internal solutions such as evaporation and electro-dialysis are two interesting technologies which reduce nitrates in combination with acid recovery. It was found that slaked lime (Ca(OH)2) is the most suitable neutralisation agent for pickling waste and, besides the choice of chemicals, many important parameters influence the process, such as the optimal pH, mixing and conditions during lime slaking. Based on information from one of the visited sites in Sweden a mass balance of the neutralisation facility was made and from that the required amount of Ca(OH)2 was calculated. The calculations were verified by an experimental part performed by IVL, using pickling acids from the same site. The amount of metals in the outgoing water was calculated using software “Medusa” but also by equilibrium equations. However, the results differed somewhat; this is probably due to the fact that Medusa takes other complexes and their interaction, besides the formed metal hydroxides, into consideration. Within the mining industry research has been made on different methods for neutralisation and some have been tested in field. An example is the High Density Sludge process (HDS), were an amount of sludge is recycled back to the neutralisation tank. It was shown that this gave improved sludge properties and decreased lime consumption. This could perhaps also be implemented for waste water in the stainless steel industry, and the method was also tested during the experimental part of this project. The dry content increased after a number of cycles but further investigation is required before any conclusion can be drawn.Betning Ă€r en enhetsprocess inom tillverkningen av rostfritt stĂ„l dĂ„ godset behandlas med fluorvĂ€te syra (HF) och salpetersyra (HNO3), ocksĂ„ kallad blandsyra. Betningen ger upphov till vatten strömmar som mĂ„ste behandlas innan de slĂ€pps ut till recipienten. Syftet med det hĂ€r examensarbetet var att göra en utvĂ€rdering av olika tekniker för att reducera utslĂ€pp till vatten frĂ„n betningen med Kina som potentiell framtida marknad. Arbetet bestod av tvĂ„ delar; den första delen var att beskriva och utvĂ€rdera olika behandlingsmetoder av förbrukade betbad med betoning pĂ„ denitrifikationstekniker. Den andra och största delen var att göra en grundlĂ€ggande beskrivning av neutralisationsprocessen. Studien utfördes genom att inhĂ€mta information frĂ„n litteratur samt frĂ„n industrin i bĂ„de Sverige och Kina. Arbetet har varit ett samarbetsprojekt mellan Kungliga Tekniska Högskolan (KTH), Svenska miljöinstitutet (IVL) och företaget Scanacon.    Arbetet behandlar syraĂ„tervinningsystemen; jonbytare, diffusions dialys samt extraktion. Nitrat reduktion kan ske internt eller externt dĂ€r de externa Ă„tgĂ€rder som behandlas i denna rapport Ă€r biologisk rening, omvĂ€nd osmos och nanofiltrering. De interna metoderna avdunstning och elektrodialys Ă€r intressanta eftersom de Ă„tervinner syran samtidigt som de reducerar nitraterna avsevĂ€rt. Studien visade att jonbyte, pĂ„ grund av dess robusthet och relativt lĂ„ga kostnad Ă€r den mest implementerade metoden för syraĂ„tervinning i bĂ„de svensk och kinesisk industri idag. Restprodukten frĂ„n jonbytaren krĂ€ver dock fortsatt behandling, dĂ€r det traditionella valet Ă€r neutralisation. Studien visade att slĂ€ckt kalk (Ca(OH)2) Ă€r det mest passande kemikalien för neutralisation av betsyror. Förutom kemikalieval sĂ„ finns det mĂ„nga parametrar som pĂ„verkar effektiviteten hos processen sĂ„ som pH, omrörning och förhĂ„llanden under kalkslĂ€ckningen. Baserat pĂ„ information ifrĂ„n ett av de besökta stĂ„lverken i Sverige, gjordes en massbalans över dess neutralisationanlĂ€ggning. UtifrĂ„n de flöden som denna gav kunde den teoretiska mĂ€ngden kalk som krĂ€vdes för utfĂ€llning rĂ€knas ut. BerĂ€kningarna verifierades med en experimentell del som utfördes av IVL pĂ„ betsyror frĂ„n samma verk. Resthalterna av metall i utgĂ„ende vatten berĂ€knades med programmet ”Medusa” men ocksĂ„ med jĂ€mviktsekvationer. Resultaten mellan de tvĂ„ skiljde sig, detta beror förmodligen pĂ„ att Medusa förutom hydroxidutfĂ€llning tar hĂ€nsyn till andra utfĂ€llningskomplex och dess interaktioner. Inom gruvvatten industrin har det forskats en del kring olika neutralisationsmetoder, en i litteraturen föreslagen sĂ„dan Ă€r ”High Density Sludge process (HDS)”. HĂ€r Ă„terförs en del av slammet tillbaka till neutralisationssteget, vilket visade sig ge förbĂ€ttrade slamegenskaper och minskad kalkĂ„tgĂ„ng. Det var intressant att undersöka om denna metod ocksĂ„ gick att implementera pĂ„ förbrukade betbad och dĂ€rför prövades metoden i den experimentella delen av detta projekt. Detta gav efter ett antal Ă„terföringscykler högre torrhalt pĂ„ slammet, dock krĂ€vs fortsatta undersökningar innan nĂ„gon slutsats kan dras

    The proinflammatory activity of recombinant serum amyloid A is not shared by the endogenous protein in the circulation.

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    OBJECTIVE: Elevated serum levels of the acute-phase protein serum amyloid A (SAA) are a marker for active rheumatoid arthritis (RA), and SAA can also be found in the tissues of patients with active RA. Based on a number of studies with recombinant SAA (rSAA), the protein has been suggested to be a potent proinflammatory mediator that activates human neutrophils, but whether endogenous SAA shares these proinflammatory activities has not been directly addressed. The present study was undertaken to investigate whether SAA in the plasma of patients with RA possesses proinflammatory properties and activates neutrophils in a manner similar to that of the recombinant protein. METHODS: Neutrophil activation was monitored by flow cytometry, based on L-selectin shedding from cell surfaces. Whole blood samples from healthy subjects and from RA patients with highly elevated SAA levels were studied before and after stimulation with rSAA as well as purified endogenous SAA. RESULTS: Recombinant SAA potently induced cleavage of L-selectin from neutrophils and in whole blood samples. Despite highly elevated SAA levels, L-selectin was not down-regulated on RA patient neutrophils as compared with neutrophils from healthy controls. Spiking SAA-rich whole blood samples from RA patients with rSAA, however, resulted in L-selectin shedding. In addition, SAA purified from human plasma was completely devoid of neutrophil- or macrophage-activating capacity. CONCLUSION: The present findings show that rSAA is proinflammatory but that this activity is not shared by endogenous SAA, either when present in the circulation of RA patients or when purified from plasma during an acute-phase response
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