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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.
21

T-RFLP analyses of biocides influence on white water micro-organisms – planktonic and in biofilm

Bodin, Rebecka Unknown Date (has links)
When paper is manufactured, deposits often form in the machines. These deposits are slimelike and can interfere with the papermaking process. The slimelike deposits are aggregates of micro-organisms, also known as biofilm. One single type of micro-organism can form a biofilm, but most biofilms consists of a mixture of several different kinds of micro-organisms and can form on about any conceivable surface. To control the aggregates of micro-organisms a slimecide is added, a so-called biocide. To examine what kind of bacteria that is included in the biofilm and also which bacteria that is killed or not killed by the biocide, Terminal Restriction Fragment Length Polymorphism analysis (T-RFLP) can be used.   In this report we examine biocides impact on biofilm produced in the laboratory.The biocides were first tested for possible interference with the PCR-step of the T-RFLP analysis. None of the tested ten biocides inhibited the PCR process the biofilm was formed on metal plates when these were lowered in a beaker with white water. Three different beakers were set up, one with addition of a biocide with active component 4,5-DICHLORO-1,2-DITHIOLONE from the start, one with the addition of the same biocide after three days and one with no addition at all of biocide. Samples were taken from the beakers and analyzed with T-RFLP.   In this report, we show that biocides affect planktonic and biofilm micro-organisms differently. There are however some micro-organisms in the biofilm that does not get affected by the biocide.   The experimental in this report is a good way of investigate the influence that biocides have on planktonic and biofilm micro-organisms, but to get even greater result the experiment should be done over a longer period of time and repeatedly.
22

Validering av metoder för analys av Cu, Fe och Na i processvatten med AAS-grafitugn / Validation of methods for analysis of Cu, Fe and Na in process water with an atomic absorption spectrometer - graphite furnace

Zweigel, Catarina January 2009 (has links)
Södra Cell Mörrum is one of the five paper pulp plants that are included in Södra Cell, and the paper pulp that is produced here is not only sold to Swedish paper mills. Most of the paper pulp is exported to different countries in Europe. In the manufacturing process the plant needs different kind of process water and there are guideline values for how much copper, iron and sodium this water is allowed to contain. Analyzes of this water is in the current situation done with an atomic absorption spectrometric instrument (AAS-instrument) with a flame.   Measurements done with flame-AAS of samples that have concentrations near the guideline values for copper, iron and sodium, are not reliable. The reason for not being reliable is that the quantitation limits of these metals are higher than the limit values. An alternative method that should give more reliable values is to analyze with an AAS- instrument with a graphite furnace. The purpose of this project was to perform a method validation of the graphite furnace of the AAS-instrument in the analysis of Cu, Fe and Na. The focus of the project was to find the detection limits for each metal, study the variation and to see if it is possible to analyze these water samples with this technique.   The concentrations of the calibration solutions is between 1-10 µg/l for Na, 5-25 µg/l for Cu and 2-20 µg/l for Fe.The detection limits for all metals were slightly below 1 µg/l and during the present circumstances in the laboratory; it would be difficult to get even lower detection limits. There are improvements that can be done to get to the even lower detection limits. The results from this work show that the variation in each sampling cup is very small but if you look at different sampling cups the variation could be large if the cups are not treated in the right way. Further validation analyzes like variation in between days needs to be done. It is possible to analyze these low concentrations of copper, iron and sodium in the water samples with the AAS- graphite furnace, but it is difficult because there are many factors that affect the results. Examples of such factors are the environment where the instrument is placed in the laboratory and the human factor. Further analyzes needs to be done to get a better view of how these factors affect the result.
23

Alternativa fröer i bröd : En teknisk och sensorisk utvärdering av amarant, bovete, chia, hirs samt quinoa i bröd och bakning

Eriksson, Emily January 2010 (has links)
Influenser från hela världen påverkar livsmedelsindustrin och användandet av fröer har ökat kraftigt de senaste åren. Idag används endast ett begränsat antal fröer inom bageriindustrin men ett intresse finns av att finna alternativa fröer som kan bidra med sina egenskaper till bröd. Syftet med det här examensarbetet är att undersöka amarant, bovete, chia, hirs och quinoa, för att se vad de kan bidra med för näringsmässiga och sensoriska egenskaper till bröd. Examensarbetet utförs vid Pågen AB. Genom en mindre litteraturstudie och ett antal bakningsförsök med efterföljande analyser av volym, inkråm, textur och vattenhalt, kartläggs fröernas närings- och bakningsegenskaper. Sensoriska analyser görs även för att undersöka dessa egenskaper hos varje frö. Av de studerade fröerna valdes chia, bovete och quinoa ut för vidare bakningsförsök. Chia och bovete valdes ut bland annat på grund av de goda resultaten från de sensoriska analyserna och försöken visade att båda fröerna fungerar bra i olika bröd, i olika mängder. Quinoas bittra smak och lukt var svår att få bort men minskade när fröet användes som dekor. Även chia och krossat bovete passade bra som dekor på bröd. Försöken visar på att det finns spännande alternativa fröer som kan bidra med mycket både när det gäller näring och smak till bröd. Vidare försök med olika brödrecept och varierade frömängder krävs för att se hur väl fröerna skulle fungera i storskaliga projekt inom bageriindustrin.
24

Milk and dairy intake and the metabolic syndrome

García Bravo, Gabriela January 2011 (has links)
The overall aim of this master thesis was to get an overview on how milk and dairy consumption affect development of the metabolic syndrome, and from this review to formulate a milk product with potentially beneficial effects. A cluster of metabolic abnormalities such as insulin resistance and type 2 diabetes, hypertension, obesity and dyslipidaemia are known as the metabolic syndrome. Epidemiological studies performed to investigate the relation between milk and dairy intake and the metabolic syndrome, suggests that low-fat milk and dairy intake have a positive effect in the prevention of the disease. Many dairy components might contribute to this effect. There are promising effects seen by whey amino acids on the glucose and insulin control, but the long-term effects are warranted. Low-fat milk and dairy as part of a diet rich in fruits and vegetables have the most blood pressure reducing effect. This beneficial effect is in part believed to be due to the calcium content of milk and dairy products. In addition, it is also hypothesised that calcium plays an important roll in weight management. However, the evidence up to date is contradictorily. Weight control, on the other hand, can be improved by affecting satiety. Acute intervention studies show that whey, in particular, alfa-lactalbumin, is more satiating than other proteins, resulting in a lower energy intake in a subsequent meal. It is of interest to the dairy industry to provide milk and dairy consumers with milk products that have beneficial effects on wellness and health. Therefore, based on the literatured reviewed on milk and dairy intake and the metabolic syndrome, a milk product with beneficial effects on weight was formulated and developed.
25

Foaming in Apple Wine

Mårtensson, Ellinor January 2010 (has links)
At Kiviks Musteri AB, situated in the southeast part of Scania, a wide variety of products based on fruits and berries, are produced. One of these products is base apple wine, which is used for the production of cider and mulled wine and also is sold to other producers of cider. A foaming problem has occurred at some customers when the cider is bottled, and this problem has been traced to the base wine. The aim of this paper is to investigate what causes the foaming and how the foaming is affected by the clarifying agents used during the production of the wine. An investigation whether silica based antifoaming agents might be a solution of the problem will be performed. During the work fermentations, clarification and foaming tests will be performed in laboratory scale in Kivik. Tests with four different silica based antifoaming compounds are carried out and on these samples the surface tension and viscosity are measured to see how these factors correlate with the foaming when antifoaming agents are added to the wine. What is more, fermentations with a new yeast type and fermentations with less fruit are made to investigate if this could give better foaming properties in the wine. The tests showed that it is probably proteins that are the main cause of the foaming, but an increase of the amount of bentonite, the clarifying agent reducing protein content in the wine, is not possible since this causes too much sediment. Antifoaming agents gave reduced foaming times, which were at an acceptable level, but when the wine was mixed to cider base and filtered the effect was lost. No significant differences were observed between the four antifoaming compounds. The test with the new yeast type gave no positive results when it came to foaming. The test with less fruit showed a decrease in foaming but not sufficient enough.
26

Studies towards a general method for attachment of a nuclear import signal. Stabilization of the m3G-Cap.

Lindvall, Mattias January 2010 (has links)
A synthetic pathway towards the cap-structure of 2,2,7-trimethylguanosine containing a methylene modified triphosphate bridge have been investigated. The modification to the triphosphate bridge is hoped to slow down cap degradation and give the connected  oligunucleotide an increased lifetime. This could result in an better understanding of nuclear transport of oligonucleotides and could thereby helping to develop new treatments for different diseases. The synthesis relies on a coupling reaction between the 2,2,7-trimethylguanosine 5’phosphate and 2’-O-methyladenosine with a 5’-pyrophosphate where the central oxygen has been replaced by a methylene group. The reaction pathway consists of 9 steps of which 8 steps have been successfully performed. The last step, which includes a coupling reaction, was attempted but without successful identification and isolation of the cap-structure, and will need further attention. The reaction has been performed in a milligram scale with various yields. / Presentation utförd
27

Immunohistochemical study of hemoglobin-related proteins in endometrium from fertile and infertile women

Sida, Abdulhak January 2012 (has links)
In couples diagnosed with unexplained infertility, the woman has normal ovulatory cycles and no organic pathology, and the man has normal semen. The period during which the implantation of an embryo can occur is defined as the window of implantation (WOI). For infertile women, disturbances in the endometrium maturation are hypothesized to impair the uterine receptivity for embryo implantaition. However, there are still no methods found to predict endometrial receptivity. Hemoglobin related-proteins hypothesized to be involved in embryo implantation have been found in the endometrium in both fertile and infertile women. The aim of this study was to determine whether there were differences in the expression of hemoglobin-related proteins, hemoglobin-α, cytoglobin, fetal hemoglobin and haptoglobin in the endometrium of fertile and infertile women. Immunohistchemical staining was used. Haptoglobin showed negative expression in glands, luminal epithelium and strong expression in stroma for both gruops. The expression of the hemoglobin-related proteins, hemoglobin-α, cytoglobin, fetal hemoglobin intensity were stronger in fertile than infertile women. More studies are required to find other factors that may have an effect on fertility.
28

Vårdpersonals upplevelser av att vårda barn och ungdomar på en vuxenpsykiatrisk avdelning : En kvalitativ intervjustudie på en sluten psykiatrisk vårdavdelning

Forsman, Johanna, Bergström, Matilda January 2012 (has links)
Syfte: Syftet med denna studie var att undersöka och beskriva vårdpersonals upplevelser av att vårda Barn och ungdoms psykiatripatienter (BUP) tillsammans med vuxna psykiatripatienter på en sluten psykiatrisk vårdsavdelning. Metod: Intervjustudie med kvalitativ ansats samt explorativ och deskriptiv design. Datainsamlingen utfördes med en semistrukturerad intervjuguide. Insamlad data analyserades med en kvalitativ latent innehållsanalys. Resultat: Två teman identifierades, Sliter trots motvind och Idéer finns men svårt att påverka beslutsapparaten. När Barn och ungdomspsykiatrin (BUP) förlades till en vuxenpsykiatrisk avdelning i Mellansverige upplevde flertalet av informanterna det som ett beslut de inte kunde påverka, att det överlag var bristande information och samarbete från BUP. Alla informanterna var eniga om att lokalerna som de använder i dag inte uppfyller en ändamålsenlig vård. Att vårda BUP-patienter tillsammans med vuxna psykiatripatienter upplevdes inte som en hållbar lösning. Slutsats: Vårdpersonal är i behov av information, stöd och samarbete med andra professioner. De måste besitta rätt kunskap för att kunna vårda barn och ungdomar med psykiska funktionshinder. Vid beslut om neddragningar inom vården bör man tänka på att det ska fungera under lång tid för alla berörda. Att förlägga Barn- och ungdomspsykiatrin till en vuxenpsykiatrisk avdelning kan fungera men inte utan att ge personalen vidare kunskap eller om det inte finns ändamålsenliga lokaler.
29

COMPARATIVE STUDY OF HYDROLYSIS PERFORMED WITH MODERN MICROWAVE TECHNIQUE AND THE TRADITIONAL METHOD

Seid Tahir, Seid Hosen January 2012 (has links)
Proteins are vital to all cells in the body. They consist of long chains of amino acids. To be able to study the amino acid composition of a protein it is necessary to hydrolyse it, followed by separation and quantification. When the protein is hydrolysed, in this case ß-lactoglobulin, the protein is divided into individual amino acids. The method that traditionally has been used to hydrolyse proteins takes 24-72 hours to complete. Recently a new microwave heating technique was introduced. With the Ethos1 microwave oven it takes less than one hour to hydrolyse proteins. The objective of this study was to see if the result of the hydrolysis with the new microwave oven technique had the same quality as the previously used method. If the microwave technique can hydrolyse proteins with as good results as the old oven, then it will significantly reduce test turnaround times. The result of this study indicates that the microwave technique is just as reliable as the older method, and thus a good and time saving alternative.
30

Fundamental Studies of Molecular Interactions in Complete Prepolymerization Mixtures of Molecularly Imprinted Polymers

Olsson, Gustaf D. January 2009 (has links)
In the present work, molecular dynamics simulations were used to evaluate the molecular interactions in prepolymerization mixtures, as occurring during production of molecularly imprinted polymers. The systems simulated were produced based on earlier studies for reference of results. Four systems were simulated in order to investigate the effect on molecular interactions based upon the choice of porogen (acetonitrile or chloroform) and proton transfers. The systems consisted of phenylalanine anilide as template, methacrylic acid as functional monomer, ethylene glycol dimethacrylate as crosslinker and 2,2’-azobis-(2-methylpropionitrile) as radical initiator, with either acetonitrile or chloroform as porogen. Trajectories from the simulations were evaluated through radial distribution function analysis, grid density analysis and hydrogen bond analysis to investigate molecular interactions and complex formations in the simulated complete prepolymerization mixtures. Focus was on functional monomer-template, crosslinker-template and template-template complex formations. The results showed that the porogen influences molecular interactions in complete prepolymerization mixtures. Formation of higher order complexes was confirmed in all of the systems involving all of the investigated molecular species in the prepolymerization mixtures. The results could also confirm the presence of previously observed complexes between functional monomer and template (2:1 and 1:1 stoichiometry) and the prevalence of template dimerization, as well as a high involvement of crosslinker in complex formation.

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