Effekter av mjölkningssystem på plasmin- och plasminogenaktiviteten i tankmjölk från ko

Protein is an important component in various milk products and has a crucial role in the final quality. Excluding non-protein nitrogen, bovine milk contains about 3.3% protein whereas about 80% of this fraction consists of casein. There are four major members in the casein family: αs1-casein, αs2- casein, β-casein and κ-casein. Proteolytic enzymes are the cause of degradation of the economically important milk proteins. By that, proteases play a more significant role than any other group of enzymes in dairy technology. The proteolytic activity is mainly achieved through activation of the serum protease plasmin. Plasmin alters from its inactive proenzyme, plasminogen and causes a degradation of the protein, such as casein. The aim of this study was to investigate if the type of milking system significantly affected the plasmin and plasminogen activity in bulk milk. Milk from automatic milking system (AMS) was compared with milk from conventional milking system (CMS). The proteolytic enzyme activity was examined by fluorescence measurement. Totally 108 bulk milk samples was included in the study, 52 and 56 from AMS and CMS farms, respectively. In addition to analysis regarding plasmin and plasminogen activity, casein content and milk features such as pH, fat, total protein and SCC were determined. Results showed significantly higher content of αs1-casein in CM milk and αs2- casein was significantly higher in AM milk. Fat and protein were significantly higher in CM milk, meanwhile results regarding pH and SCC showed higher amount in milk derived from AMS. Percentage of proteolytic enzyme activity was significant higher (PL: 17% and PG: 7%) in CMS milk in comparison to AMS milk, suggesting that quality of the protein fraction is better preserved in milk from AMS farms.Protein är en betydelsefull komponent i olika mjölkprodukter och har en avgörande roll för dess kvalité. Undantaget icke proteinbundet kväve, innehåller komjölk ca 3.3% protein och ca 80% av den totala proteininnehållet består av kasein. Kaseinfraktionen består av αs1-kasein, αs2- kasein, β-kasein och κ-kasein. Proteolytiska enzymer är orsaken till nedbrytningen av det ekonomiskt viktiga proteinet. I och med detta spelar proteaserna en mer betydande roll än någon annan grupp av enzymer inom mejeriindustrin. Den proteolytiska aktiviteten uppnås främst genom aktivering av serumproteaset plasmin. Plasmin transformeras från dess inaktiva proenzyme, plasminogen, och orsakar därefter en nedbrytning av främst kasein. Syftet med denna studie var att undersöka om olika typer av mjölkningssystem har någon signifikant inverkan på plasmin- och plasminogenaktiviteten i tankmjölk. Mjölk från automatiskt mjölkningssystem (AMS) jämfördes med mjölk från konventionellt mjölkningssystem (CMS). Den proteolytiska enzymaktiviteten undersöktes genom fluorescensmätning. Totalt 108 tankmjölksprover ingick i studien, 52 från AMS gårdar och 56 från gårdar med CMS. Utöver analys av plasmin- och plasminogenaktivitet, fastställdes andelen kaseininnehåll samt övriga mjölkkomponenter såsom pH, fett, protein och SCC. Resultat visade på en signifikant högre halt av αs1-kasein i CM-mjölk medan andelen αs2- kasein var signifikant högre i AM-mjölk. Fett och protein var signifikant högre i CM-mjölk, medan resultat gällande pH och SCC visade på en högre andel i mjölk som härrörde från AMS. Procentandel av proteolytisk enzymaktivitet (PL: 17% and PG: 7%) var signifikant högre i CM-mjölk i jämförelse med AMS mjölk, vilket tyder på att proteinets kvalitet bevaras bättre i mjölk från gårdar med AMS

Riskbedömning och val av betesmark för boskap i torra till halvtorra områden i Kenya

The Rift Valley i Kenya utgör ett hem för de pastorala massajerna. De baserar primärt sitt leverne på kött, mjölk samt blod, därför är vikten av boskap av stor betydelse. För att upprätthålla en god och uthållig produktion bör flertal parametarar beaktas. I detta arbete undersöks vilka risker som massajernas djurbesättning utsätts för under betesgång samt vilka val herdarna gör för att minimera förekomsten av dessa riskfaktorer. De risker som primärt berörs är infektionssjukdomen trypanosomiasis (en sjukdom som sprids av tsetseflugor), olika fästingburna sjukdomar samt andra infektioner. Vidare nämns även predatorer samt konflikter mellan herdar och åkerbönder som en förekommande riskfaktor. Genom att utvärdera utförandet av en redan pågående studie i ämnet och en vidare analys av dessa data, skulle denna studie kunna bidra till en bättre förståelse av vilka risker som är störst i dessa studieområden. Vidare hur åtgärderna ser ut, samt strategier för att parera dessa risker. På grund av fältassistenternas bristande kommunikation och engagemang kunde tillförlitliga data endast erhållas från två utav 11 assistenter. Därmed kunde inga slutsatser dras som besvarade de frågor som ställts innan utförd studie, utan endast tidigare studier kunde användas för att beskriva massajernas olika strategier. En strategi att minska risken för predation är att boskapen vistas endast en begränsad tid vid vattenkällan. Dessutom minskar även angrepp av fästingar och tsetseflugor då denna risk är betydligt större i dessa områden. Studier har påvisat vikten av god avel, där raser eller individer med en naturlig motståndskraft kan bidra till en ökad resistens mot sjukdomar. Ett annat alternativ för bekämpning av fästingar är med hjälp av en så kallad ko-dipp. Det var dock inte en fungerande verksamhet för de två besättningar som studerades. Det finns utrymme för förbättring som skulle leda till effektivare djurhållning. Enligt egen erfarenhet visade det sig att även terrängen var av vikt när det gällde riskbedömningen. Befann sig boskapen i tät terräng med merparten buskage var predationsrisken stor. Vidare beskrivs fördelen med att besättningen fick vatten endast en gång per dag, detta medförde att boskapen på grund av törst höll ett högre tempo på vägen hem och på så vis minimerades risken för predation.The Rift Valley in Kenya is the home of the pastoral maasai. This ethnic group primarily bases their livelihood on meat, milk, and blood. Hence, livestock is of great importance. In order to maintain a good and sustained production several parameters should be monitored. This work examines the risks that maasai herds are exposed to during grazing and the choices shepherds make to minimize the presence of these risk factors. The risks that are involved are primarily infectious diseases like trypanosomiasis, a disease caused by the tsetse fly, various tick-borne diseases and other infections. Furthermore, predators and conflicts between pasture and crop farmers are common risk factors. By studying methods and outcomes of a larger ongoing study on the subject and the quality of its data, the results were thought to contribute to a better understanding of which risks are most important in the study areas and what are the counter-strategies. Due to the field assistants’ lack of communication and involvement, reliable data were obtained by two of the 11 field assistants. Thus, no conclusions could be drawn that answered the questions that were asked before conducting the study. Hence, only previous studies and personal communication could describe how herders different strategies can be enacted. One such strategy is that the cattle should only stay for a limited time around the water source since the risk of predation is high and the infestation of ticks and tsetse flies is much greater in these areas. Previous studies have also stressed the importance of breeding since breeds or individuals with a natural resistance can contribute to increased disease resistance when included in the breeding strategies. Another option for the control of ticks is using a so-called cow dip. This, however, was not working optimally in this area, so there is room for improvement that might generate more effective results. From personal experience, the terrain was of importance for current risk assessment. When cattle were kept in dense terrain with bushes and shrubs, the risk of predation was of great significance. Furthermore the maasai talked about the benefits of cattle receiving water only once per day. This meant that the cattle due to thirst maintained a higher speed when walking back home, minimizing the risk of predation

RNA and DNA interactions with zwitterionic and charged lipid membranes — A DSC and QCM-D study

AbstractThe aim of the present study is to establish under which conditions tRNA associates with phospholipid bilayers, and to explore how this interaction influences the lipid bilayer. For this purpose we have studied the association of tRNA or DNA of different sizes and degrees of base pairing with a set of model membrane systems with varying charge densities, composed of zwitterionic phosphatidylcholines (PC) in mixtures with anionic phosphatidylserine (PS) or cationic dioctadecyl-dimethyl-ammoniumbromide (DODAB), and with fluid or solid acyl-chains (oleoyl, myristoyl and palmitoyl). To prove and quantify the attractive interaction between tRNA and model-lipid membrane we used quartz crystal microbalance with dissipation (QCM-D) monitoring to study the tRNA adsorption to deposit phospholipid bilayers from solutions containing monovalent (Na+) or divalent (Ca2+) cations. The influence of the adsorbed polynucleic acids on the lipid phase transitions and lipid segregation was studied by means of differential scanning calorimetry (DSC). The basic findings are: i) tRNA adsorbs to zwitterionic liquid-crystalline and gel-phase phospholipid bilayers. The interaction is weak and reversible, and cannot be explained only on the basis of electrostatic attraction. ii) The adsorbed amount of tRNA is higher for liquid-crystalline bilayers compared to gel-phase bilayers, while the presence of divalent cations show no significant effect on the tRNA adsorption. iii) The adsorption of tRNA can lead to segregation in the mixed 1,2-dimyristoyl-sn-glycerol-3-phosphatidylcholine (DMPC)-1,2-dimyristoyl-sn-glycero-3-phosphatidylserine (DMPS) and DMPC–DODAB bilayers, where tRNA is likely excluded from the anionic DMPS-rich domains in the first system, and associated with the cationic DODAB-rich domains in the second system. iv) The addition of shorter polynucleic acids influence the chain melting transition and induce segregation in a mixed DMPC–DMPS system, while larger polynucleic acids do not influence the melting transition in these system. The results in this study on tRNA–phospholipid interactions can have implications for understanding its biological function in, e.g., the cell nuclei, as well as in applications in biotechnology and medicine

Streetscapes: behind the scenes

Planning processes are often disconnected from the experienced place on the ground. Ideologies of space, developing agendas, time constraints and budgets serve to limit the understanding of the lived world of those dwelling in an area and stand at risk to reduce it to the abstract space of maps. This induces territorial control from above and an ignorance of the soft, social values of the individual. Urbanization and globalization are reshaping our world and demands knowledge, understanding and change. It generates changes in the urban fabric with growing class differences and an increasing physical and social fragmentation. The majority of this change is taking place in the global South, putting an immense pressure on the informal settlements in the cities. Future urban planners have a big task in turning this into a sustainable and equal process. However, planners keep imposing planning ideals from above, shaped by western ideologies of space that are disregarding slums as becoming one of the major human habitats. The relation between the life world on the ground and the system world of the planner remain distant. How can planners and landscape architects understand and manage their role in these processes better? This thesis set out to explore that relationship. The first phase of that task was undertaken through a field study in Nairobi, Kenya. Today, Nairobi host more than 200 informal settlements that are the home to more than half of the cities population. The authors of the thesis got the opportunity to make a report for UN-Habitat, who has recently introduced a new approach to slum upgrading that is emphasizing the role of streets as an entry point. Focus in the report was the Korogocho Street Upgrading Programme that involved the upgrading of the major streets in Korogocho Slum in Nairobi. The Street Upgrading Project was studied from multiple levels though the interaction with residents in Korogocho, policy makers, politicians and project planners. The streets were considered to be a field where multiple strategies and tactics of the actors were played out, shaping the experience of it and its future development. It demonstrated many dimensions and symbolic meanings, highlighting several conflicts between the system world and the life world. Consequently, the thesis is a reflection upon the authors’ own working process in Nairobi, and how they were affected by the system world of international organizations such as UN-Habitat, policy making processes, the life world of the resident of Korogocho and their own world as landscape architecture students. Theory, narratives and reflections comment on the content of the published UN-report that was finalized in Nairobi, issues and phenomena encountered in Korgocho, at the UN-Headquarters and through interviews with local government agents. Furthermore, the methods and tools used in the making of the report are commented, elaborated and evaluated. This serves as an elaboration on the complex relationship between ideologies of space, the multiple realities on the ground, and how this complicated issue can be approached as a practicing landscape architect or planner. 0

Färggladare friskare sjukhusgård : snabbt, experimenterande och lekfullt

Inspirerade av en föreläsning på Arkitektur- dagen 2006 om en arkitekturskola i USA, Rural Studio, ville vi försöka göra något liknande. Där arbetar studenterna hela vägen med projekten, från förslag via finansiering till byggande och vi bestämde att ett liknande projekt skulle passa bra som kandidatarbete. Olika platser besöktes och slutligen valde vi Barnsjukhusets utegård. Tanken var att visa att det är möjligt att genomföra en relativt stor förändring på kort tid och till liten kostnad. Vi ville förbättra gården redan till sommaren så att fler skulle kunna ta del av de goda sidorna av utevistelse. Vårt projekt skulle fungera som en första etapp i gårdens om- formning, där steg två startar hösten 2007 och skall resultera i ett mer permanent förslag för hela gårdens nästa etapp. Tidigt i projektet fick vi veta att viss finansiering från Barnfonden var möjlig. Vi blev också kontaktade av föreningarna Ladies Circle och Round Table som kom att samla in pengar till barnsjukhusets utegård som välgörenhetsprojekt. Knappt hälften av budgeten ordnade vi på egen hand sponsorer till, inklusive ett eget kontor i centrum. Personalen på sjukhuset ansåg bristen på skugga som ett av de stora problemen och de efterlyste också mer lekfullhet och inbjudande platser. Efter vår analys blev målet att ge hela gården en färgstark lekfull känsla, dela in den i fler avskilda rum, skapa några skug- giga platser, och dessutom ge barnen möj- lighet att själva sätta sina avtryck på gården. Vi fokuserade på att använda billiga, lättåtkomliga och i viss mån, återavända material. Eftersom ingen av oss har hantverkskunskap strävade vi efter att hitta lösningar som var möjliga för oss att anlägga själva. Vi ville heller inte göra några större ingrepp på gården, utan vår installation skulle gå att avlägsna utan större spår. Skisser och modeller användes tillsammans med experiment i full skala. Vårt förslag delade in gården i tre zoner, för vila, lek och tonår. De befintliga svängda linjerna på gården översattes till ett generellt cirkeltema. Trästolpar i cirklar skapade rum och plywoodskivor mellan vissa av dem gav skugga. Målade traktorinnerslangar och cirklar på asfalten fullföljde temat. Mycket tid gick åt att organisera och samordna och telefonsamtalen var många. Vissa mindre problem som leverans- förseningar och fel färger dök upp, men det mesta fungerade som vi tänkt

Aviation fuel and future oil production scenarios

Most aviation fuels are jet fuels originating from crude oil. Crude oil must be refined to be useful and jet fuel is only one of many products that can be derived from crude oil. Jet fuel is extracted from the middle distillates fraction and competes, for example, with the production of diesel. Crude oil is a limited natural resource subject to depletion and several reports indicate that the world's crude oil production is close to the maximum level and that it will start to decrease after reaching this maximum. A post Kyoto political agenda to reduce oil consumption will have the same effect on aviation fuel production as a natural decline in the crude oil production. On the other hand, it is predicted by the aviation industry that aviation traffic will keep on increasing. The industry has put ambitious goals on increases in fuel efficiency for the aviation fleet. Traffic is predicted to grow by 5% per year to 2026, fuel demand by about 3% per year. At the same time aviation fuel production is predicted to decrease by several per cent each year after the crude oil production peak is reached resulting in a substantial shortage of jet fuel by 2026. The aviation industry will have a hard time replacing this with fuel from other sources, even if air traffic remains at current levels

Aviation fuel and future oil production scenarios

Most aviation fuels are jet fuels originating from crude oil. Crude oil must be refined to be useful and jet fuel is only one of many products that can be derived from crude oil. Jet fuel is extracted from the middle distillates fraction and competes, for example, with the production of diesel. Crude oil is a limited natural resource subject to depletion and several reports indicate that the world's crude oil production is close to the maximum level and that it will start to decrease after reaching this maximum. A post-Kyoto political agenda to reduce oil consumption will have the same effect on aviation fuel production as a natural decline in the crude oil production. On the other hand, it is predicted by the aviation industry that aviation traffic will keep on increasing. The industry has put ambitious goals on increases in fuel efficiency for the aviation fleet. Traffic is predicted to grow by 5% per year to 2026, fuel demand by about 3% per year. At the same time, aviation fuel production is predicted to decrease by several percent each year after the crude oil production peak is reached resulting in a substantial shortage of jet fuel by 2026. The aviation industry will have a hard time replacing this with fuel from other sources, even if air traffic remains at current levels.Aviation fuels Peak oil Future air traffic scenarios

RNA and DNA interactions with zwitterionic and charged lipid membranes - A DSC and QCM-D study.

The aim of the present study is to establish under which conditions tRNA associate with phospholipid bilayers, and to explore how this interaction influence the lipid bilayer. For this purpose we have studied association of tRNA or DNA of different size and degree of base pairing with a set of model membrane systems with varying charge density, composed of zwitterionic phosphatidylcholines (PC) in mixtures with anionic phosphatidylserine (PS) or cationic dioctadecyl-dimethyl-ammoniumbromide (DODAB), and with fluid or solid acyl-chains (oleoyl, myristoyl and palmitoyl). To prove and quantify the attractive interaction between tRNA and model-lipid membrane we used quartz crystal microbalance with dissipation (QCM-D) monitoring to study the tRNA adsorption to deposited phospholipid bilayers from solutions containing monovalent (Na(+)) or divalent (Ca(2+)) cations. The influence of the adsorbed polynucleic acids on the lipid phase transitions and lipid segregation was studied by means of differential scanning calorimetry (DSC). The basic findings are: i) tRNA adsorb to zwitterionic liquid-crystalline and gel-phase phospholipid bilayers. The interaction is weak and reversible, and cannot be explained only on basis of electrostatic attraction. ii) The adsorbed amount tRNA is higher for liquid-crystalline bilayers compared to gel-phase bilayers, while the presence of divalent cations show no significant effect on the tRNA adsorption. iii) The adsorption of tRNA can lead to segregation in the mixed 1,2-dimyristoyl-sn- glycerol-3-phosphatidylcholine (DMPC)- 1,2-dimyristoyl-sn-glycero-3- phosphatidylserine (DMPS) and DMPC-DODAB bilayers, where tRNA is likely excluded from the anionic DMPS-rich domains in the first system, and associated with the cationic DODAB-rich domains in the second system. iv) The addition of shorter polynucleic acids influence the chain melting transition and induce segregation in mixed DMPC-DMPS system, while larger polynucleic acids do not influence the melting transition in these system. The results in this study on tRNA-phospholipid interactions can have implications for its biological function in, e.g., the cell nuclei, as well as in applications in biotechnology and medicine