Towards a human body model for prediction of vehicle occupant kinematics in omni-directional pre-crash events

As the vehicle fleet becomes more equipped with crash avoidance systems, the proportion of crashes preceded by evasive manoeuvres is expected to increase. In an evasive manoeuvre, occupant position and posture can be influenced by the induced loading. Therefore, there is a need to predict the occupant response from evasive manoeuvres. During evasive manoeuvres, the occupant kinematics can also be affected by muscle activity, and as such, taking the effect from active muscles into account in simulations of occupant response to evasive manoeuvres is important.In this thesis, a method for activation of the neck and lumbar muscles in an active human body model, based on recorded muscle activity from volunteers, was enhanced and evaluated. The active human body model successfully predicted passenger kinematics in lane change, braking, and combined manoeuvres. As a step towards a model capable of predicting driver kinematics in evasive manoeuvres, the same method was adapted to control the shoulder muscles. The model with active shoulder muscles was evaluated in a simplified test setup. The active model successfully predicted peak elbow displacement for all loading directions.Based on the results from the included studies, an active muscle controller based on directionally dependent muscle activity data can successfully predict kinematics from reflex response to loading in a finite element human body model. These findings represent an important step towards developing an active human body model able to predict occupant kinematics and muscle forces in omni-directional pre-crash events

SAFER HBM in 9kph sled simulations - selection of torso skin and flesh material properties

In a comparison of kinematic predictions of the active enhanced SAFER HBM v9 to volunteer kinematics in braking and lane change, it was found that the model gave a stiffer response than the volunteers. To soften the model, the skin material of the torso and buttock, and the solid layer in the torso (flesh), was updated. To evaluate which combination of flesh material and skin material is best suited for low-loading simulations, all possible skin/flesh combinations were simulated and compared to two 9 kph PMHS tests. Simulation results showed that the most suitable combination for low-speed simulations was a flesh model tuned to average adipose tissue stiffness, and an orthotropic skin model using skin tension lines (Langer lines)

Passenger kinematics in evasive maneuvers

In situations that might lead to a vehicle crash, drivers often perform an evasive maneuver, such as braking or steering, in an attempt to avoid a crash. If a crash was not avoided, the maneuver could influence the injury outcome by altering the occupant’s position. Occupants use their muscles in response to a maneuver, and because the typical accelerations are low during maneuvers, the muscle activity can influence the kinematics. Thus, it is important to include the response to these potential maneuvers before the crash when predicting occupant injuries in a crash. The response to maneuvers could be evaluated by adding active musculature to existing evaluation tools, such as human body models. Furthermore, in volunteer studies, the head and torso displacements during maneuvers vary between occupants, but the cause for this variability remains to be identified. Two aims were defined for this thesis, addressed in two parts. The first aim was to advance the active neck and lumbar muscle controllers in the SAFER HBM to predict average response to maneuvers. The second aim was to further understand why such variability is seen in occupant response to evasive maneuvers.Three muscle controller concepts were evaluated in this thesis, two of which were aimed at emulating the reflexes responding to input from the vestibular system that control the head position in space, and one controller that emulated reflexes that respond to lengthening of muscles. For the first aim, the active muscle controllers in the SAFER HBM were updated to allow for simulations with large vehicle yaw rotations, and the predictive capabilities were evaluated in braking, steering, and combinations. In a subsequent study, the updated controllers were tuned to volunteer kinematics in braking and steering, and the model performance was evaluated in the same conditions. It was concluded that the SAFER HBM, with the updated and tuned controllers, could predict passenger head kinematics in braking and steering with good to excellent results.The occupant variability was addressed by statistical analysis of volunteer kinematics in six different vehicle maneuvers. In two subsequent studies, the Active Human Body Model developed within the first aim was used to analyze the model sensitivity to Human Body Model and boundary condition characteristics in braking. From the analysis of volunteer kinematics, it was concluded that the belt system was the most influential predictor for head and torso displacements across all maneuvers, while other characteristics such as sex, stature, age, and body mass index were less influential. In the subsequent studies, the seat forward/rearward position and spinal curvature were found to be most influential in braking

Sambandet mellan αs1-kasein, proteolytisk aktivitet och sammansättning i mjölk från svenska getter

In the recent decade, locally produced food has gained in interest among Swedish consumers. Consumer values for buying local food has to do with concerns about diversity, purity and authenticity of food as well as a desire to support rural areas. One type of product that has gained in interest is locally produced goat cheese. The goat industry in Sweden is small scaled, however, steadily increasing. In goats, the CSN1S1 gene regulates the expression of the protein αS1-casein (αS1-CN). This casein has been found to be important for the cheese yield. Over the years, breeding animals have been imported to Sweden from Norway. Historically a high frequency of the Norwegian goat population carried a polymorphism at the CSN1S1 gene. This polymorphism, called the Norwegian null allele (D), leads to zero or heavily reduced expression of αS1-CN. Consequently, in Sweden, the number of goats homozygous for the Norwegian null allele, increased dramatically. This study aimed to investigate how the expression of αS1-CN and the genetic profile of the CSN1S1 gene influence the proteolytic activity and milk composition of milk from Swedish dairy goats. Within the study, milk samples from 75 goats were analysed for total proteolysis, plasmin activity (PL) and plasminogen derived activity (PG). Total proteolysis was determined by a luminescent method, measuring the amount of free terminal amino groups present in the milk. For PL and PG analysis, a spectrophotometric method with chromogenic substrate was used, where PG was activated with urokinase. The results for gross composition, somatic cell count, protein profile and genotype were also included in this investigation. Milk samples were grouped according to level of αS1-CN (low 0-6.9% and medium-high 7-25% of total protein) and genotype (DD, DG and DA/AG/AA). For the statistical analysis, Pearson and Spearman correlations were applied. The groups were compared with two-sample T-test and one-way ANOVA. The frequency of individuals homozygous for the Norwegian null allele (DD) was 58%, and only 15% of the studied goats carried an A allele. A significant association was found between the level of αS1-CN in the milk and allele combination (p <0.001). Moreover, a significant positive correlation was found between αS1-CN with total protein (p ≤ 0.001). Total protein was negatively correlated with total proteolysis (p ≤ 0.001) and PG (p ≤ 0.01) and positively correlated with PL (p ≤ 0.05). However, no correlation between total proteolysis and PL was found. SCC, pH and FFA were significantly higher among the genotype homozygous for the null allele (DD) compared to genotypes with an A allele (p ≤ 0.05). This may have effects on milk processability and the sensory properties of the processed dairy product. Further research is needed to understand the relationship between αS1-CN and proteolytic activity, for example including additional parameters within the plasmin-plasminogen system such as the activity of plasminogen activators and plasmin inactivators. In addition, the bacterial status of the milk could be included.Lokalt och småskaligt producerad mat har under de senaste åren erhållit ett ökat intresse hos de svenska konsumenterna. De värderingar som är drivande för att köpa lokalt producerad mat har bland annat att göra med mångfald och autenticitet, samt att konsumenten vill stödja landsbygden. En produkt med en ökad efterfrågan är lokalt producerad getost. Den svenska getindustrin är småskalig men har en uppåtgående trend. Hos getter finns en gen, CSN1S1, som reglerar uttrycket av proteinet αS1-kasein (αS1-CN). Detta kasein har i studier observerats vara gynnsamt för ostutbytet. Avelsdjur har förts från Norge till Sverige varför den svenska lantrasen är nära besläktad med den norska getpopulationen. Historiskt har en hög andel av den norska getpopulationen burit på en mutation i αS1-CN genen. Som en konsekvens, har antalet getter med den norska genvarianten ökat kraftigt inom den svenska getstammen. Denna studie syftade till att undersöka hur uttrycket av αS1-CN och den genetiska profilen av genen CSN1S1 påverkar proteolytisk aktivitet och mjölksammansättning i mjölk från svenska getter. Studien inkluderade mjölkprover från 75 getter som analyserades för totalproteolys samt aktivitet av plasmin (PL) och plasminogen (PG). Totalproteolys bestämdes med en luminiscensmetod genom att mäta mängden fria, terminala aminogrupper i mjölken. För PL och PG användes en spektrofotometrisk metod och ett kromogent substrat, varvid PG aktiverades med urokinas. Resultat för mjölksammansättning, somatiska celltal, proteinprofil och genotyp inkluderades också i denna undersökning. Mjölkproverna grupperades utifrån mängden αS1-CN i mjölken (låg 0-6,9% och medium-high 7-25% av totalprotein) och genotyp (DD, DG och DA/AG/AA). I den statistiska analysen testades korrelationer med Pearson och Spearman. Skillnad mellan grupper testades med t-test och envägs ANOVA. Andelen individer som var homozygoter för den norska null-allelen var 58% och endast 15% av individerna bar på en A-allel. Ett signifikant förhållande observerades mellan mängd αS1-CN i mjölken och kombinationen av alleler (p <0,001). Vidare observerades en positiv korrelation mellan αS1-CN och totalprotein (p ≤ 0,001). Totalprotein uppvisade en negativ korrelation med totalproteolys (p ≤ 0,001) och PG (p ≤ 0,01) och en positiv korrelation med PL (p ≤ 0,05). Studien kunde inte påvisa en korrelation mellan totalproteolys och plasmin. Medelvärdena för somatiskt celltal, pH-värde och fria fettsyror var signifikant högre i gruppen som var homozygoter för null-allelen (DD) jämfört med gruppen med A-alleler (p ≤ 0,05). Resultatet kan ha effekt på mjölkens lämplighet för vidare förädling samt för sensoriska egenskaper hos slutprodukten. Ytterligare studier krävs för att förstå relationen mellan αS1-CN och proteolytisk aktivitet. Ett förslag är att inkludera fler parametrar så som aktiviteten av aktivatorer av plasminogen samt inhibitorer av plasmin. Vidare bör även den mikrobiologiska statusen för mjölken inkluderas i framtida studier

slipp ångest - använd kondom. En fokusgruppstudie om några gymnasieungdomars attityder kring sexuellt beteende

Syftet med vår undersökning är att undersöka några gymnasieungdomars kunskap och uppfattningar beträffande sexuellt beteende samt hur ungdomarna menar att man omsätter dessa i praktiken. Vi har använt oss av följande frågeställningar för att närma oss vårt syfte: • Vad har ungdomarna för kunskap och inställning till könssjukdomar, främst klamydia? • Vad anser ungdomar om användandet av preventivmedel i allmänhet och kondom i synnerhet? • På vems ansvar och under vilka omständigheter sker och förhandlas säkrare sex? • Vilken inställning har ungdomar vad gäller tillfälliga sexuella förbindelser och antal partners? • Tänker killar (pojkar) och tjejer (flickor) lika om detta eller finns det könsskillnader i deras uppfattningar och beteende? För att kunna fördjupa vår studie har vi valt att använda oss av de två datainsamlingsmetoderna fokusgrupper och vinjettmetoden. Användandet fokusgrupper handlade om att vi ansåg att denna metod skulle hjälpa oss att få en mer övergripande bild av ämnet. Den hjälper oss att se processer och diskussioner i en grupp, vilket också var det vi ville koncentrera oss på. Vinjettmetoden valde vi för att ungdomarna skulle få prata om fiktiva personer och händelser i stället för att behöva prata om sig själva. Resultatet av vår undersökning visar att ungdomar oroar sig i högre utsträckning för en graviditet än att få klamydia. Klamydia är så pass lätt att bota att man inte tycker det är mycket värre än en förkylning. Ungdomarna anser att kondom är det säkraste och bästa preventivmedlet, samtidigt som det också är det mest besvärliga. Det kan vara pinsamt att ta upp att man vill använda kondom, bland annat för att man är rädd att förstöra stämningen. Att ha sex utan att ha ett förhållande är något som är ganska vanligt hos ungdomar. Samtidigt som det är accepterat är det till viss del tabu och resulterar ibland i ifrågasättande hos omgivningen. Skillnaden mellan att vara KK och tillsammans är för ungdomarna svårt att beskriva. I teorin är det okej att ha haft sex med många, men i praktiken kan det medföra att dessa personer ses som en ”hora” eller en ”player”. Att en tjej har haft sex med många är mer negativt än om en kille har det. En bedömning av risk, hur säkert, eller osäkert, det är att ha sex med personen i fråga, görs ofta när man träffar en ny partner. Har man haft sex med få personer, och inom förhållanden, ses detta som seriöst. Seriösa personer bedöms som säkrare att ha sex med än oseriösa. Att ha känslor för en person påverkar också riskbedömningen. Ungdomarna tycker det är svårare att tro att en person man känner eller är kär i har en könssjukdom

Green areas during the grey season : a site analysis based on health-promoting environmental qualities

Psykisk ohälsa är ett problem i dagens samhälle. I Sverige ökar den psykiska ohälsan och av årstidsrelaterade depressioner är vintern den årstid som dominerar i statistiken. Forskning inom miljöpsykologi visar att utemiljöer kan fungera hälsofrämjande bland annat genom att bidra till återhämtning. Arbetets syfte är att identifiera kvaliteter i utemiljöer vintertid som främjar psykisk hälsa genom att ta fram ett ramverk och tillämpa det vid platsanalys. Arbetet ämnar bidra med kunskap kring hur stadsplanering och gestaltning av utemiljöer vintertid kan förebygga psykisk ohälsa samt bidra till återhämtning av exempelvis utmattning, depression och ångest. En platsanalys av Flogsta utförs. Resultaten visar att Flogsta erhåller ett flertal utemiljöer med kvaliteter som främjar psykisk hälsa. Å andra sidan brister området i vinterkvaliteter, speciellt när det kommer till de gestaltade element som skulle kunna öka kvaliteten på platserna. Exempel på detta är brist på skydd mot oönskat väder, på tillgängliggörandet av tydliga vinteraktiviteter och en generell brist på vinteranpassning i utemiljöerna. Det är istället förekomsten av mer naturlika områden som bidrar med många av kvaliteterna som kan nyttjas året om. Bristen på vinteranpassning antas resultera i minskad användning av utemiljöerna vintertid och därmed påverka de boendes psykiska hälsa. Med studien ville vi kunna bidra till att fylla den kunskapslucka som finns inom forskningen i hur utemiljöer påverkar människor under vintern. Med ramverkets hjälp kunde kvaliteter identifieras men samtidigt är ramverket i behov av utveckling för att nå sin fulla potential.Mental illness is a problem when it comes to public health today. In Sweden mental illness increases and the wintertime contribute to the majority of cases of seasonal depression. Research in environmental psychology show that the outdoor environment can serve as a resource of recovery and rehabilitation. The aim of this essay is to identify qualities in outdoor environments during winter that contribute to mental health through creating a framework and applying it to a field analysis. The study aims to contribute with knowledge on how city planning and design can prevent mental illness and have a positive impact on recovery of mental disorders such as fatigue, depression and anxiety. A site analysis is applied on Flogsta. The results show that in general the residents of Flogsta have access to a wide range of public outdoor spaces with qualities that contribute to mental health. On the other hand the area lacks winter qualities, especially when it comes to urban planning and man-made elements that could contribute to the quality of the spaces. Many of the health benefiting qualities in the area will only reach the people in the warmer months since there is no protection against bad weather, lack of winter activities and no clear adaptation to the colder months. Areas with nature contributes with qualities all year round. The lack of adaption to winter is assumed to result in less use of the outdoor environment in wintertime which is a lost opportunity to promote mental health. With the study we wanted to contribute to more research about how outdoor environments can affect mental health in the wintertime. With help of the framework we could identify qualities but at the same time the framework can be improved to reach its full potential

Fermentation performance and physiology of two strains of Saccharomyces cerevisiae during growth in high gravity spruce hydrolysate and spent sulphite liquor

Background: Lignocellulosic materials are a diverse group of substrates that are generally scarce in nutrients, which compromises the tolerance and fermentation performance of the fermenting organism. The problem is exacerbated by harsh pre-treatment, which introduces sugars and substances inhibitory to yeast metabolism. This study compares the fermentation behaviours of two yeast strains using different types of lignocellulosic substrates; high gravity dilute acid spruce hydrolysate (SH) and spent sulphite liquor (SSL), in the absence and presence of yeast extract. To this end, the fermentation performance, energy status and fermentation capacity of the strains were measured under different growth conditions. Results: Nutrient supplementation with yeast extract increased sugar uptake, cell growth and ethanol production in all tested fermentation conditions, but had little or no effect on the energy status, irrespective of media. Nutrient-supplemented medium enhanced the fermentation capacity of harvested cells, indicating that cell viability and reusability was increased by nutrient addition. Conclusions: Although both substrates belong to the lignocellulosic spruce hydrolysates, their differences offer specific challenges and the overall yields and productivities largely depend on choice of fermenting strain

Risk, resilience and identity construction in the life narratives of young people leaving residential care

The role of residential care for children has developed very differently internationally, but in all cultural contexts there are questions about the extent to which it can help young people recover from high risk backgrounds. In the UK, residential care has come to be seen as the placement of last resort, yet new government guidance on permanence has suggested that residential care can provide security and a sense of belonging. Narrative analysis of interviews with 20 care leavers identified their different pathways from birth families through residential care to early adulthood. Some experienced a transformation from a negative sense of self as victims or ‘bad children’ to survivors, while others continued to struggle. Key to successful turning points were four interacting factors, all associated with resilience; connection, agency, activity and coherence. These narratives revealed the importance of nurturing relationships and a sense of ‘family’, but also the role of support after leaving residential care, when transitions workers helped them to move on but stay connected. The study highlighted how residential care leavers from adverse backgrounds attribute very different meanings to their experiences, which affects identity construction, resilience and the need for support

Optimisation of surface expression using the AIDA autotransporter

<p>Abstract</p> <p>Background</p> <p>Bacterial surface display is of interest in many applications, including live vaccine development, screening of protein libraries and the development of whole cell biocatalysts. The goal of this work was to understand which parameters result in production of large quantities of cells that at the same time express desired levels of the chosen protein on the cell surface. For this purpose, staphylococcal protein Z was expressed using the AIDA autotransporter in <it>Escherichia coli</it>.</p> <p>Results</p> <p>The use of an OmpT-negative <it>E. coli </it>mutant resulted in successful expression of the protein on the surface, while a clear degradation pattern was found in the wild type. The expression in the mutant resulted also in a more narrow distribution of the surface-anchored protein within the population. Medium optimisation showed that minimal medium with glucose gave more than four times as high expression as LB-medium. Glucose limited fed-batch was used to increase the cell productivity and the highest protein levels were found at the highest feed rates. A maintained high surface expression up to cell dry weights of 18 g l^-1could also be achieved by repeated glucose additions in batch cultivation where production was eventually reduced by low oxygen levels. In spite of this, the distribution in the bacterial population of the surface protein was narrower using the batch technique.</p> <p>Conclusions</p> <p>A number of parameters in recombinant protein production were seen to influence the surface expression of the model protein with respect both to the productivity and to the display on the individual cell. The choice of medium and the cell design to remove proteolytic cleavage were however the most important. Both fed-batch and batch processing can be successfully used, but prolonged batch processing is probably only possible if the chosen strain has a low acetic acid production.</p