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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
261

Svenskodlade bondbönor som proteinkälla till köttsubstitut : Miljöpåverkan, odling, förädling och tillverkning / Swedish Grown Broad Bean as a Meat Substitute, Environmental Impact, Cultivation, Processing and Manufacturing

Elfström, Caroline January 2014 (has links)
Sojabönor är en global gröda med odlingar i bland annat Brasilien, Kina och USA och i de köttsubstitut som säljs i Sverige baseras ungefär hälften av dem på sojaprotein. I Sverige domineras baljväxtodlingen av ärter och åkerbönor som blir djurfoder och odlingarna av baljväxter för humankonsumtion är mindre omfattande. Konsumenter i Sverige har dock fått ett ökat intresse för livsmedel med svenskt ursprung. För att öka variationen i den svenska baljväxtodlingen, bemöta konsumenters efterfrågan på inhemska livsmedel och minska miljöpåverkan i länder där sojabönorna produceras, har bondbönors möjligheter till att ersätta sojabönor i köttsubstitut undersökts. Metoden har varit en litteraturstudie som har kompletterats med en kvalitativ intervju med en person som är marknadsansvarig på ett köttsubstitutföretag. Kemiska föroreningar i naturen, minskad biodiversitet och för stor färskvatten användning är tre globala problem som uppmärksammats i Kina, USA och/eller Brasilien. På dessa faktorer ger svenskodlade bondbönor en lägre miljöpåverkan än sojabönor från dessa länder. Odlingen av bondbönor för humankonsumtion i Sverige har möjlighet att öka med ca 59 000 ha och de kan även samodlas med spannmål. Bristande tillgång till tillräckligt stora mängder bondbönor året runt samt avsaknaden av en förädling av bönorna till texturerat protein utgör de största hindren för att svenskodlade bondbönor ska börja användas i köttsubstitutprodukter. Näringsvärdet och egenskaperna hos bondbönor bör inte utgöra ett hinder. Problemen verka ligga i leden innan tillverkningen.
262

Estrogenic Substances in Plastic Bottles

Karlsson, Frida January 2014 (has links)
We live in a time were plastic and plastic products are all around us, taking part in our everyday life. Several chemical additives can be present in plastic products, such as plastic bottles, and can have a big impact on development, as well as on the endocrine system in adults by the binding to, and disturbance of, the estrogen receptor (ER) in cells. This study has focused on a number of different plastic bottles made from different types of plastic and with variations in size and scope of use. The aim of the study was to see if any estrogenic substances leached from the bottles into water. Non-ionic water was added to the plastic bottles, and the bottles were kept at 70°C for 72 hours. The estrogenic activity in the water was determined with the U2OS-luc assay and expressed as bioassay-derived estradiol equivalents (Bio-EEQ). A difference in Bio-EEQ could be detected between the bottles and the tree plastic types used in the study. The polypropylene (PP) bottle gave the highest Bio-EEQ of 0.5 pg/ml, whereas High Density Polyethylene (HDPE) gave 0.3 pg/ml and Polyethylene Terephthalate (PET) 0.04 pg/ml. These results indicate that there is a small leakage of estrogenic substances from the plastic bottles. Further study is needed to determine whether or not the estrogenic activity in the water could have any significant biological effect in humans. / Vi lever i en tid där plast och plastprodukter finns överallt runt omkring oss och har en stor del i vår vardag. Många kemiska ämnen kan återfinnas i plastprodukter, såsom plastflaskor, och kan ha en stor inverkan inte bara på den växande kroppen hos barn utan även ge endokrina störningar hos vuxna människor. Detta kan till exempel ske genom att ämnen kan binda till och påverka östrogenreceptorn (ER) i cellerna. Den här studien fokuserar på plastflaskor gjorda av olika typer av plast och med varierande storlek och användningsområde. Syftet med studien var att se huruvida några östrogena substanser kunde lakas ut i vatten som förvarades i flaskorna. Flaskorna fylldes med avjoniserat vatten och förvarades i 70°C i 72 timmar. Östrogenaktiviteten i vattnet mättes sedan i en cellbaserad testmetod, kallad U2OS-luc assay, där den samlade biologiska effekten av alla östrogena ämnen kan mätas. Effekten uttrycks som bioassay-derived estradiol equivalents (Bio-EEQ). Vatten från polypropenflaskan (PP) gav det högsta Bio-EEQ på 0,5 pg/ml medan högdensitetspolyeten (HDPE) gav 0,3 pg/ml och polyetylentereftalat (PET) ett Bio-EEQ på 0,04 pg/ml. Dessa resultat indikerar att plastflaskorna läcker ut små mängder östrogenlika ämnen. Vidare studier behöver göras för att avgöra huruvida detta läckage utgör någon risk för människor.
263

Migration of Xenoestrogens from Plastic Food Containers during Cooking

Vigren, David January 2015 (has links)
Xenoestrogens are compounds, foreign from the body, that can enter cells and interact with the estrogen receptors (ER) to produce an estrogenic response. Many additives used in plastics are compounds with estrogenic activity. Some of these additives are known to slowly leach from the plastics. When using plastic containers as lunchboxes for reheating or food storage, these additives can leach from the plastics and end up in the food. In this project, food simulates were cooked in six different thermoplastic containers, made of polypropylene, in an oven at 100 °C for 15 minutes. Three of the thermoplastic containers were lunchboxes marketed to be able to withstand cooking in a microwave. The other three were provisional lunchboxes made from various food storing containers originally made for refrigeration purposes. The estrogenic activity in the different samples was measured using an ER-CALUX in vitro assay. The results were measured in 17β-estradiol equivalent (Bio-EEQ) values in pg/ml. The purpose of this project was to investigate whether or not these plastic containers leach xenoestrogens that can be measured with an ER-CALUX assay, and compare the results with the results from other existing toxicological studies, and also to see if there is a difference in Bio-EEQ levels between the plastic containers made for microwave usage and those made for refrigerated purposes. The results from this project indicate that most of these plastic containers do leach estrogenic compounds that can be detected in the ER-CALUX, even the ones made for microwave usage. Fortunately, compared to other toxicological studies, the Bio-EEQ levels in these food samples cooked in plastic containers are low. However the potential adverse effects in prenatally exposed children cannot be ignored as other studies have shown that very low levels of xenoestrogens are enough to potentially cause a disturbance in the reproductive development and fertility.
264

The Influence of Agroforestry on Soil Fertility in Coffee Cultivations : A Review and a Field Study on Smallholding Coffee Farms in Colombia

Ekqvist, Ida January 2015 (has links)
Coffee is, together with cacao, the crop most commonly cultivated under shade trees in order to cope with physiological stress (as drought and sun radiation) and erosion as well as to generate additional income for the farmer. However, today this agroforestry coffee management is increasingly transformed into industrial plantation with little or no shade using varieties that tolerates full sun and can be planted with higher density. This conversion most often brings an intensified use of external input, such as fertilizers and pesticide, and a reduction in biodiversity as well as long term soil fertility. The objective of this study was to examine whether the inclusions of trees in coffee cultivations favour soil fertility and how it affects the output of the system. The aspect of output was not only delimited to the weight of coffee yield but take a broader perspective that comprises the farmer’s economy. This was done by conducting a review of previous research on the subject combined with a field study performed at six smallholding coffee farms with different levels of shade in Colombia from November to December 2014. The results of the field study serve as a site specific example and are discussed in relation to previous findings. Soil samples was taken at the farms and analysed for organic matter, soil moisture, respiration rate and acidity. The hypothesis was that the inclusion of trees in coffee cultivations can enhance the long term soil fertility when compared to monoculture systems. And also that agroforestry coffee can bring an increased safety for the farmer in terms of income, when compared to monoculture coffee. No general conclusions could be drawn based on the results from the field study; however the results show that a change from agroforestry management to monoculture management in coffee cultivations in Colombia can have a significant negative effect on soil respiration rate. Furthermore the study highlights the importance of taking into account the specific characteristics of the location and the management of the investigated farm when making conclusions about the effects of agroforestry on soil fertility. It is also concluded that long term studies, extending over at least a year, is necessary to fully see the effects of the cultivation practice on soil fertility.
265

Effects of Persistent Organic Pollutants and Their Mixtures on Biotransformation and Oxidative Stress in Zebrafish Embryo

Jeong, Hyon Sun January 2016 (has links)
Persistent organic pollutants (POPs) cause significant effects on organisms due to their resistance to environmental degradation and specific toxic responses. Although POPs toxicities were linked to oxidative stress in the previous studies, there are few POPs studies that link them with oxidative stress in zebrafish during development. Aim of this study is to investigate effect of selected POPs on expression of genes involved in oxidative stress response and biotransformation of xenobiotics in zebrafish. Zebrafish embryos in 96 hours’ post-fertilization were exposed to selected POPs and their mixture. To explore the developmental toxicity in zebrafish early stage, we exposed 3,3',4,4',5-pentachlorobiphenyl (PCB), perfluorooctanesulfonic acid (PFOS) and perfluorohexanoic acid (PFHxA) at concentrations of 7.5 μg/L, 50 μM, 50 μM until 96 hours’ post-fertilization. The effects were measured by gene expression quantification technique - quantitative real-time PCR (qPCR). Significant up-regulation in gene expression was detected in embryos treated with mixture of PCB with PFHxA and PCB with PFOS only for cytochrome P450(cyp1a). The results also showed the treatment with selected compound caused significant higher upregulation of cyp1a when we compare the treatment in the individual compounds to the mixture compounds. However, treatments did not cause changes in expression of genes involved in oxidative stress response (glutathione peroxidase 1a(gpx1a), tumor protein p53(tp53), aryl hydrocarbon receptor 2 (ahr2)). The result also suggests that exposure to selected POPs in mixtures or alone is not causing oxidative stress in early stage of embryonal development of zebrafish but activating biotransformation function of the organism. Effect of activation of biotransformation capacity by means of cyp1a upregulation is also higher when POPs are in mixtures over when used as individual substance.
266

Utbildning av urbana matproducenter - Framtidens nya matproduktionsnäring? / Education of Urban Food Producers. Future Prospectives.

Matsson, Anna January 2014 (has links)
Denna studie har genomförts som en del i Mistra Urban Futures projekt Grön Produktion. Projektet vill utveckla stadsodlingsprojekt och affärsidéer och har beslutat att göra detta genom att titta på områdena utbildning och affärsmodeller. Denna studie riktar sig mot området utbildning och har undersökt hur utbildning skulle kunna öka urban matproduktion för att bidra till skapandet av en ny matproduktionsnäring och samtidigt öka städers ekologiska hållbarhet. Frågeställningar som behandlades var hur en utbildning av urbana matproducenter skulle kunna stärka och lyfta befintlig matproduktion i städer till en ny matnäring, vilka kunskaper som urbana jordbrukare har och önskar samt vilka kunskaper som marknaden önskar. För att besvara detta genomfördes kvalitativa intervjuer av olika aktörer inom den potentiella matproduktionsnäringen; kommunen, odlare, handeln och restaurangbranschen. Svaren har sedan diskuterats mot relevant litteratur inom området. Studien visar att en yrkesutbildning har potential att öka intresset för urban matproduktion genom att legitimera urban matproducent som yrke samtidigt som det svarar mot nya behov som uppkommer på marknaden. Studien visar också att en utbildning behöver vara anpassningsbar för att kunna locka både erfarna och oerfarna urbana jordbrukare. För att kunna bidra till en ökad ekologisk hållbarhet behöver utbildningen innehålla kurser som lär ut miljövänliga odlingstekniker samtidigt som det behöver vara ett fokus på hög avkastning då tanken är att studenterna efter avslutad utbildning ska kunna jobba med kommersiell produktion. Om en utbildning av urbana matproducenter leder till en ökad urban matproduktion med fler grönytor i staden ökar stadens resiliens, både genom grönytornas buffrande förmåga vid klimatförändringar och genom att det skapar städer med en högre självförsörjningsgrad. Ett kommersiellt urbant jordbruk kan komplettera det rurala jordbruket genom att utöka utbudet och tillgången till färska produkter med en kortare hållbarhet.
267

Apiculture and Bee Health in Central Sweden

Larne, Olof January 2014 (has links)
Pollination necessary for the agricultural crop production affects the functions of the ecosystems on earth. In landscapes where wild pollinators are decreasing, honey bees promote the maintenance of plant species, therefore honey bee losses are of great concern. Current honey bee colony losses (Apis mellifera) worldwide are caused by Colony collapse disorder, the mite Varroa destructor and pesticides. This results in the honey bees weakened immune defenses making them susceptible to different diseases. Studies show that long-term natural selection for coexistence, or resistance to Varroa mites by honey bees is possible, but further developments are needed for this application in managed beekeeping. Furthermore, lactic acid bacteria found in honey bees can play a crucial role by improving its immune response. At places where apicultural practices have led to decreased amounts of lactic acid bacteria in the bees, supplementary feeding is a possible treatment solution. The beekeepers' observations of mite reproduction dynamics and the overwintering of strong and healthy honey bees are needed to decrease Varroa treatment with synthetic chemicals. Based on this knowledge, a small survey of beekeepers in Örebro County, Sweden, was conducted in an attempt to determine the status of their bees during the last 5 years. The largest colony loss over the past 5 winters was predominantly in 2012-2013. Varroa mite infestations with disease symptoms were primarily found in the central region. Since the survey was small and time was limited it was only possible to make general conclusions. Deeper understanding of lactic acid bacteria in honey bee societies and their inhibition of different diseases are important for future research.
268

Tillagningsmetodens påverkan på perfluorerade ämnen i Vätternröding / Influence of Cooking Methods on Levels of Perfluoroalkyl Substances in Lake Char from Lake Vättern

Rasmussen, Alice January 2014 (has links)
Denna studie har undersökt tre tillagningsmetoder; kokning, stekning och ugnsbakning för att se om halten per- och polyfluorerade alkylsubstanser (PFAS) förändras efter tillagning i vätternröding. Proverna har testats för perfluoralkyl sulfonat (PFSA)/perfluorkarboxylsyror (PFCA), polyfluoroalkyl fosfater (PAPs) och perfluoroktan sulfonamid (FOSA)/ perfluoro-1-oktansulfonamid etanol (FOSE). Den substans som hittades i högst halt var perfluoroktansulfonat (PFOS). Resultatet visar att tillagad röding har lägre halter PFAS än färsk röding vilket tyder på att tillagningsmetoden påverkar PFAS, detta är intressant då tidigare forskning inte gett entydiga resultat. Resultatet tyder inte på någon risk för normalkonsumenter att överstiga tolerabelt dagligt intag (TDI) för PFAS vid konsumtion av vätternröding.
269

Role of Selective Estrogen Receptors B Agonist on Chronic Lymphocytic Leukemia Growth in Vitro

Salam, Noor January 2014 (has links)
The estrogen receptor alpha (ERa) and estrogen receptor beta (ER~) have been demonstrated to be important for immune system regulation and studies have suggested an antiproliferative effect of ER~ in lymphoid malignancies. We have studied the expression of ERa and ER~ in peripheral blood mononuclear cells from patients with chronic lymphocytic leukemia (CLL). Expression of ERa was low, while ER~ was highly expressed in CLL cells. In order to investigate the possible inhibitory effect of ligand-activated ER~ , we treated CLL cells and Mecl cell lines with the selective ER~ agonist diarypropionitrile (DPN) in culture. Treating Mecl cell lines with DPN showed an antiproliferative effect of ER~ agonist by significantly inhibit the growth of Mec 1 cell lines. This suggests that ER~ agonist may be useful in the treatment of CLL.
270

Cold-induced vasodilation in the brood patch of Zebra finches (Taeniopygia guttata)

Klubb, Sofia January 2010 (has links)
The development of the avian embryo is dependent of heat provisioning from the parents. To increase the heat transfer to a cooled egg the Zebra finch females develop a brood patch. Mild cooling generally constricts the blood vessels but the Arterio-venous anastomoses (AVA) in the brood patch in birds dilate. This is called cold-induced vasodilation CIVD. The Zebra finches were anesthetized with isoflurane and the brood patch was stimulated with a cooling probe set at 20-21 °C. Differences in the vascular changes to cooling in broody and non- broody birds were studied by comparing males and broody females. The brood patch skin was cooled, but no cold-induced vasodilation (CIVD) was documented for the males or the broody females. Isoflurane anesthesia depresses the sympathetic nervous system activity and the results support that the mechanism for CIVD in the brood patch of Zebra finches depends on a neural pathway, but does not exclude a local non-neural mechanism.

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