296 research outputs found
Växtnäring från trekammarbrunnar till energigräs
En slutsats som dragits inom projektet är att själva kretsloppet för växtnäringsinnehållet i
trekammarbrunnsslam inte är den viktigaste frågan ur hållbarhetssynpunkt vid odling av
energigräs, eftersom återföringen av växtnäring med trekammarbrunnsslam, främst fosfor och
kalium, är mycket begränsad. I stället är själva nyttjandet av energigräset som råvara för
produktion av förnybara drivmedel mycket viktigare ur hållbarhetssynpunkt. Hållbarheten i
systemet ligger i att energigräset kan omvandlas till förnybara drivmedel, såsom biogas och
bioetanol, vilka ersätter bensin och diesel, som har en mycket stor klimatpåverkan. Enligt
litteraturuppgifter ger en vallgröda på ca 9 ton torrsubstans (ts) per ha och år, en reduktion av
växthusgasemissioner med ca 6 ton CO2-ekv. per hektar och år, under förutsättning att
fordonsgas i form av metan produceras av vallgrödan och biogödseln, som kvarstår efter
rötningen av vallgrödan, ersätter mineralgödsel på produktiv åkermark.
Inom projektet har vi uppnått skördar på 5 - 15 ton ts per ha och år beroende på odlingslokal
och vilket energigräs som odlats, om gräset varit gödslat eller ogödslat samt om baljväxter
ingått i ”biogasvallen”. Skördenivåer i detta intervall tyder på att man kan uppnå ett hållbart
system för produktion av biogas baserat på energigräs, enligt EU:s nuvarande hållbarhetskriterier
(en CO2-reduktion på minst 35 %) för förnybara drivmedel, oberoende om gräset
gödslas med trekammarbrunnsslam eller ej. Särskilt stor klimatnytta uppnås vid användning
av biogasvallar som innehåller både gräs och baljväxter, eftersom dessa ger hög biomassaavkastning
helt utan kvävegödsling. Biogaspotentialen hos de energigräs och biogasvallar
som studerats i projektet ligger normalt i intervallet 250 – 350 l CH4 per kg VS, beroende på
skördetidpunkt och förbehandlingsmetod.
Att använda energiåkrar för odling av fleråriga energigräs där biomassan används för
produktion av biogas, bioetanol eller fastbränsle innebär flera miljövinster, mest påtagligt
genom minskad klimatpåverkan, eftersom fossil energi ersätts, men även genom att fleråriga
grödor har lägre behov av insatser i form av jordbearbetning och ogräsbekämpning och lagrar
in mer kol i rötterna och marken än ettåriga grödor. Ytterligare miljövinster kan erhållas om
biomassa skördas på ogödslade energiåkrar nära känsliga vattenmiljöer, eftersom man då kan
transportera bort växtnäring till produktiv åkermark, som annars skulle kunna orsaka övergödning.
Vid användning av energigräs som biogassubstrat kan biogödseln, som blir kvar
efter rötningen, användas som ett värdefullt gödselmedel inom ekologisk eller konventionell
odling. Biogödseln innehåller lättillgänglig växtnäring och om den används för gödsling av
livsmedelsgrödor på åkermark sker en stor miljövinst genom ersättning av mineralgödsel.
För att trekammarbrunnsslam skall kunna användas som ett gödselmedel till energigräs så
krävs det en hygienisering genom t.ex. tillsats av minst 0,6 % urea och lagring i minst 3
månader. Hygienisering med urea medför dock att trekammarbrunnsslammet får ett relativt
högt kväveinnehåll i jämförelse med andra viktiga växtnäringsämnen, såsom fosfor och
kalium. Detta innebär att fosfor och kalium måste tillföras med andra gödselmedel för att
energiåkern inte skall lida brist på dessa växtnäringsämnen på längre sikt. Tillförseln av tungmetaller
med det hygieniserade trekammarbrunnsslammet till energiåkern bedöms vara något
större jämfört med om källsorterat klosettvatten eller nötflytgödsel används som gödselmedel
till energigräsen. Halterna av miljöstörande organiska ämnena i trekammarbrunnsslam ligger
dock långt under riktvärdena för avloppsslam enligt slamöverenskommelsen. Allt detta visar
att hygieniserat trekammarbrunnsslam kan användas som en växtnäringsresurs vid odling av
energigräs eller biogasvallar på energiåkrar, men att hygieniserat klosettvatten skulle vara ett
väl så bra alternativ
Living conditions, including life style, in primary-care patients with nonacute, nonspecific spinal pain compared with a population-based sample: a cross-sectional study
Odd Lindell, Sven-Erik Johansson, Lars-Erik Strender1Center for Family and Community Medicine, Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, Huddinge, SwedenBackground: Nonspecific spinal pain (NSP), comprising back and/or neck pain, is one of the leading disorders behind long-term sick-listing, including disability pensions. Early interventions to prevent long-term sick-listing require the identification of patients at risk. The aim of this study was to compare living conditions associated with long-term sick-listing for NSP in patients with nonacute NSP, with a nonpatient population-based sample. Nonacute NSP is pain that leads to full-time sick-listing>3 weeks.Methods: One hundred and twenty-five patients with nonacute NSP, 2000–2004, were included in a randomized controlled trial in Stockholm County with the objective of comparing cognitive–behavioral rehabilitation with traditional primary care. For these patients, a cross-sectional study was carried out with baseline data. Living conditions were compared between the patients and 338 nonpatients by logistic regression. The conditions from univariate analyses were included in a multivariate analysis. The nonsignificant variables were excluded sequentially to yield a model comprising only the significant factors (P <0.05). The results are shown as odds ratios (OR) with 95% confidence intervals.Results: In the univariate analyses, 13 of the 18 living conditions had higher odds for the patients with a dominance of physical work strains and Indication of alcohol over-consumption, odds ratio (OR) 14.8 (95% confidence interval [CI] 3.2–67.6). Five conditions qualified for the multivariate model: High physical workload, OR 13.7 (CI 5.9–32.2); Hectic work tempo, OR 8.4 (CI 2.5–28.3); Blue-collar job, OR 4.5 (CI 1.8–11.4); Obesity, OR 3.5 (CI 1.2–10.2); and Low education, OR 2.7 (CI 1.1–6.8).Conclusions: As most of the living conditions have previously been insufficiently studied, our findings might contribute a wider knowledge of risk factors for long-term sick-listing for NSP. As the cross-sectional design makes causal conclusions impossible, our study should be complemented by prospective research.Keywords: nonspecific spinal pain, back pain, neck pain, long-term sick-listing, population-based sample, cross-sectional stud
Risk of obesity in immigrants compared with Swedes in two deprived neighbourhoods
<p>Abstract</p> <p>Background</p> <p>Despite a strong social gradient in the prevalence of obesity, there is little scientific understanding of obesity in people settled in deprived neighbourhoods. Few studies are actually based on objectively measured data using random sampling of residents in deprived neighbourhoods. In addition, most studies use a crude measure, the body mass index, to estimate obesity. This is of concern because it may cause inaccurate estimations of the true prevalence and give the wrong picture of the factors associated with obesity. The aim of this study was to estimate the prevalence of, and analyse the sociodemographic factors associated with, three indices of obesity in different ethnic groups settled in two deprived neighbourhoods in Sweden.</p> <p>Methods</p> <p>Height and weight, waist circumference and body fat percentage were objectively measured in a random sample (n = 289). Sociodemographic data were obtained through a survey. Established cut-offs were used to determine obesity. Country of birth was categorized as Swedish, Other European, and Middle Eastern. Odds ratios were estimated by unconditional logistic regression.</p> <p>Results</p> <p>One third of the sample was classified as obese overall, with 39.0% of women being abdominally obese. After adjusting for age, we found higher odds of obesity in Middle Eastern women than in Swedish women regardless of outcome with odds ratios ranging between 2.74 and 5.53. Men of other European origin had higher odds of BMI obesity than Swedish men. Most associations between country of birth and obesity remained in the full model.</p> <p>Conclusion</p> <p>This study demonstrates the magnitude of the obesity problem and the need for prevention programmes targeting native and immigrant adults in deprived neighbourhoods in Sweden. The initiatives should also focus on particular groups, e.g. immigrant women and those experiencing economic difficulties. Further studies are needed on behavioural and environmental factors influencing the risk of obesity in residents settled in deprived neighbourhoods.</p
Cardiovascular risk factors in Assyrians/Syrians and native Swedes with type 2 diabetes: a population-based epidemiological study
<p>Abstract</p> <p>Background</p> <p>A large number of people throughout the world have diabetes and the prevalence is increasing. Persons with diabetes have a twice higher risk of cardiovascular disease than those without diabetes. There is a lack of studies focusing on cardiovascular risk factors in Assyrians/Syrians with type 2 diabetes. The aim of this study is to estimate the prevalence of some cardiovascular risk factors among Assyrians/Syrians and native Swedes with type 2 diabetes and to study whether the association between ethnicity and cardio-vascular risk factors remains after adjustment for age, gender, employment status and housing tenure.</p> <p>Methods</p> <p>In the Swedish town of Södertälje 173 Assyrians/Syrians and 181 ethnic Swedes with type 2 diabetes participated in a study evaluating cardiovascular risk factors such as increased haemoglobin A1c (HbA1c), high blood lipids (total serum cholesterol and triglycerides), hypertension and high urinary albumin. The associations between the outcome variables and sociodemographic characteristics were estimated using unconditional logistic regression.</p> <p>Results</p> <p>The prevalence of increased triglycerides in Swedish-born subjects and Assyrian-Syrians was 61.5% and 39.7% respectively. Swedes had a prevalence of hypertension 76.8% compared to 57.8% in Assyrians/Syrians. In the final logistic models adjusted for gender, age, housing and employment the odds ratio (OR) for Swedish-born subjects for increased triglycerides was 2.80 (95% CI1.61-4.87) and for hypertension 2.32 (95% CI 1.35-4.00) compared to Assyrians-Syrians.</p> <p>Conclusion</p> <p>Ethnic Swedes had higher prevalence of increased triglycerides and hypertension than Assyrians/Syrians. Total cholesterol, HbA1c and urinary albumin did not differ between the two ethnic groups.</p
Industrihampa för produktion av bioetanol
Samhället av idag står inför stora utmaningar. Höga koldioxidhalter i atmosfären, smältande isar vid våra poler, plastberg som flyter omkring i haven, föroreningar av luft, mark och vatten, ökad population osv. Ytterligare ett problem är att den fossila oljan håller på att ta slut. Vi behöver alltså hitta hållbara lösningar, som sparar på jordens resurser, som bidrar till en hållbar livsmedelsförsörjning och som samtidigt bidrar till en modern livsstil med hög levnadsstandard. Biomassa från växter lyfts fram på många sätt som framtidens lösning. Biomassa ska ge hållbara drivmedel, kemikalier, material etc. och har potentialen att bidra med detta. Syftet med detta projekt var att undersöka om industrihampa kan användas för framställning av bio-drivmedlet etanol och om användandet av hampa för detta ändamål var ekonomiskt lönsamt. Resultaten visade att förbehandlingen av hampan innan jäsningen till etanol var den faktor som spelade störst roll för etanolutbytet och därmed för lönsamheten av etanolproduktionen från hampa. Förbehandling av hampan med 1% svavelsyra vid 180oC ledde till den största etanolavkastningen. Denna förbehandling ledde också till ett positivt ekonomiskt resultat för användning av hampa för etanolproduktion. Projektet testade också om ekologisk eller konventionell produktion av hampa påverkade det ekonomiska utfallet av hampaproduktion för etanolproduktion, men fann endast en liten skillnad beroende på skillnad i maskinkostnader
Longitudinal age-and cohort trends in body mass index in Sweden - a 24-year follow-up study
Background: The aim of this longitudinal study was to analyze whether mean Body Mass Index (BMI), assessed at four occasions, changed within different age groups and birth cohorts over time, i.e., between 1980/81 and 2004/05, after adjustment for possible confounders. Methods: A sample of 2728 men and 2770 women aged 16-71 years at study start were randomly drawn from the Swedish Total Population Register and followed from 1980/81 to 2004/05. The same sample was assessed on four occasions during the 24-year study period (i.e., every eighth year). The outcome variable, BMI, was based on self-reported height and weight. A mixed model, with random intercept and random slope, was used to estimate annual changes in BMI within the different age groups and birth cohorts. Results: Mean BMI increased from 24.1 to 25.5 for men and from 23.1 to 24.3 for women during the 24-year study period. The annual change by age group was highest in the ages of 32-39, 40-47 and 48-55 years among men, and in the ages of 24-31, 32-39, and 40-47 years among women. The highest annual changes were found in the youngest birth cohorts for both men and women, i.e., those born 1958-65, 1966-73, and 1974-81. For each birth cohort, the annual change in BMI increased compared to the previous, i.e., older, birth cohort. In addition, age-by-cohort interaction tests revealed that the increase in BMI by increasing age was higher in the younger birth cohorts (1966-1989) than in the older ones. Conclusions: Public health policies should target those age groups and birth cohorts with the highest increases in BMI. For example, younger birth cohorts had higher annual increases in BMI than older birth cohorts, which means that younger cohorts increased their BMI more than older ones during the study period
Economic viability of protein concentrate production from green biomass of intermediate crops: A pre-feasibility study
Green biomass is a major potential source of proteins for food and feed. This pre-feasibility study evaluates the use of green biomass of buckwheat, phacelia, hemp and oilseed radish grown as intermediate crops (IC) as a feedstock for production of protein concentrates to produce protein-rich food and feed products. We investigated the biomass yield, protein concentration and protein recovery potential of non-fertilized IC, nitrogen-fertilized IC and IC intercropped with legumes, harvested in late summer to autumn during 2017 and 2018 in southern Sweden. In addition, economic assessment of potential protein and fibre feed and food products were evaluated. The results showed that IC fertilized with 40 kg ha1 N and intercropping with legumes contributed to a higher biomass dry matter (DM) yield of 4.9e5.8 t ha1 as compared to between 2.2 and 3.1 t ha1 for non-fertilized IC. Intercropping with legumes also resulted in higher protein yield of 154 g kg1 vs. 103 g kg1 for non-fertilized IC. Among IC, hemp, phacelia and oilseed radish showed up to ca. 25% higher DM yield and up to ca. 70% higher protein concentration as compared to buckwheat. Higher DM yield was obtained when IC were harvested in October and November than in August and September. Economic assessment was made on two feasible protein production pathways; (A) Green and white proteins and (B) total recoverable combined protein fraction (CPF). For all IC, cost per t DM was higher in August due to lower biomass yield as compared to other harvesting months. Nitrogen concentration was the main factor determining the size of revenues. Nitrogen concentration was 34% higher in 2018 compared to 2017 and therefore resulted in higher revenues in that year. Intercropping resulted in higher protein content and therefore contributed to lower breakeven prices of recovered green proteins for all IC. Breakeven price analyses showed that green protein and CPF were economically feasible to market as both bulk and premium products depending on lower (2 V kg1 ) or higher (2e10 V kg1 ) price ranges, respectively. The results demonstrate that use of IC biomass could be a feasible option to produce high value protein-rich products, which can contribute extra income from IC for farmers
High prevalence of type 2 diabetes in Iraqi and Swedish residents in a deprived Swedish neighbourhood - a population based study
Background: Immigrants from the Middle-East are at high risk of developing type 2 diabetes (T2D). The aim of the present survey was to measure, in a single deprived neighbourhood, the prevalence rates of impaired fasting glucose (IFG), impaired glucose tolerance (IGT) and T2D in residents originating from Iraq and to compare them to those in residents born in Sweden. An additional aim was to identify metabolic, lifestyle and socioeconomic risk factors associated with IFG/IGT and T2D in these residents. Methods: The study was conducted February 1'st to March 31'st 2010. Men and women aged 45 to 65 years of Swedish or Iraqi origin, living in the neighbourhood of Rosengard, Malmo, Sweden, were randomly selected from the census register. Each participant signed a written informed consent form, underwent a physical examination and an oral glucose tolerance test (OGTT), provided blood samples and filled in a questionnaire. A total of 175 subjects participated (Swedish origin n = 79, Iraqi origin n = 96), reflecting an overall response rate of almost 60%. Results: In total, 21.9% and 19.0% of the Iraqi and Swedish participants, respectively, suffered from T2D, while 24.0% of the Iraqi participants and 25.3% of the Swedish participants had IFG/IGT. There were no significant differences in prevalence rates relating to country of origin. Obesity (BMI >= 30 kg/m(2)) and sedentary leisure time physical activity were highly prevalent in both groups, while a family history of diabetes was more prevalent in participants from Iraq (49.2%) than in those from Sweden (22.8%) (p = 0.001). Being obese or having a sedentary leisure time were, independently associated with T2D (OR 5.43 (95% CI 2.10-14.02) and 2.89 (95% CI 1.03-8.10) respectively), while economic difficulties were independently associated with IFG/IGT (OR 2.55 (95% CI 1.06-6.15)) after adjustment for the confounding effects of other common risk factors for T2D. Conclusions: This study reveals a high prevalence of T2D, independently of country of origin (Iraq or Sweden), in a socially vulnerable area and additionally presents a risk factor profile that is markedly different from that of Sweden in general
Творческий подход студентов в изучении гистологии
Denna rapport innehåller texter som presenterats vid en konferens arrangerad inom ramen för Nätverk för barnomsorgsforskningi . Syftet med konferensen var att lyfta upp begreppet omsorg, diskutera dess innebörd, rädda det från retorisk förflackning och samtidigt via dess koppling till verksamheter belysa ett vidare sammanhang. När bamforskning diskuteras har jag på senare tid funnit det väsentligt att peka på att den har en kapacitet att kasta ljus över centrala samhällsfrågor. Forskning om barn bör inte bara vara en forskning om en viss grupp i samhället. Den nyare bamdomsforskningen söker tillämpa ett bamperspektiv. Detta innebär att fenomen studeras såsom de framstår från barnens perspektiv och att inverkan av olika sociala reformer, politiska förändringar och produktion av varor på barns liv belyses. Det handlar alltså både om att söka efter barnens perspektiv och att söka efter konsekvenserna för barnen av olika samhälleliga förändringar. Nya fålt som t.ex. barndomshistoria, barndomssociologi och barndomsantropologi har uppstått och begreppet generation har införts för att markera vikten av att anlägga ett generationsperspektiv på frågor som vanligtvis grupperats på annat sätt
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