28 research outputs found
Difference in force direction during propulsion between subjects with different push-off locations
Metabolic engineering of <i>Synechocystis </i>sp. PCC 6803 for production of the plant diterpenoid manoyl oxide
[Image: see text] Forskolin is a high value diterpenoid with a broad range of pharmaceutical applications, naturally found in root bark of the plant Coleus forskohlii. Because of its complex molecular structure, chemical synthesis of forskolin is not commercially attractive. Hence, the labor and resource intensive extraction and purification from C. forskohlii plants remains the current source of the compound. We have engineered the unicellular cyanobacterium Synechocystis sp. PCC 6803 to produce the forskolin precursor 13R-manoyl oxide (13R-MO), paving the way for light driven biotechnological production of this high value compound. In the course of this work, a new series of integrative vectors for use in Synechocystis was developed and used to create stable lines expressing chromosomally integrated CfTPS2 and CfTPS3, the enzymes responsible for the formation of 13R-MO in C. forskohlii. The engineered strains yielded production titers of up to 0.24 mg g(–1) DCW 13R-MO. To increase the yield, 13R-MO producing strains were further engineered by introduction of selected enzymes from C. forskohlii, improving the titer to 0.45 mg g(–1) DCW. This work forms a basis for further development of production of complex plant diterpenoids in cyanobacteria
Regulation and splicing of scavenger receptor class B type I in human macrophages and atherosclerotic plaques
BACKGROUND: The protective role of high-density lipoprotein (HDL) in the cardiovascular system is related to its role in the reverse transport of cholesterol from the arterial wall to the liver for subsequent excretion via the bile. Scavenger receptor class B type I (SR-BI) binds HDL and mediates selective uptake of cholesterol ester and cellular efflux of cholesterol to HDL. The role of SR-BI in atherosclerosis has been well established in murine models but it remains unclear whether SR-BI plays an equally important role in atherosclerosis in humans. The aim of this study was to investigate the expression of SR-BI and its isoforms in human macrophages and atherosclerotic plaques. METHODS: The effect of hypoxia and minimally modified low-density lipoprotein (mmLDL), two proatherogenic stimuli, on SR-BI expression was studied in human monocyte-derived macrophages from healthy subjects using real-time PCR. In addition, SR-BI expression was determined in macrophages obtained from subjects with atherosclerosis (n = 15) and healthy controls (n = 15). Expression of SR-BI isoforms was characterized in human atherosclerotic plaques and macrophages using RT-PCR and DNA sequencing. RESULTS: SR-BI expression was decreased in macrophages after hypoxia (p < 0.005). In contrast, SR-BI expression was increased by exposure to mmLDL (p < 0.05). There was no difference in SR-BI expression in macrophages from patients with atherosclerosis compared to controls. In both groups, SR-BI expression was increased by exposure to mmLDL (p < 0.05). Transcripts corresponding to SR-BI and SR-BII were detected in macrophages. In addition, a third isoform, referred to as SR-BIII, was discovered. All three isoforms were also expressed in human atherosclerotic plaque. Compared to the other isoforms, the novel SR-BIII isoform was predicted to have a unique intracellular C-terminal domain containing 53 amino acids. CONCLUSION: We conclude that SR-BI is regulated by proatherogenic stimuli in humans. However, we found no differences between subjects with atherosclerosis and healthy controls. This indicates that altered SR-BI expression is not a common cause of atherosclerosis. In addition, we identified SR-BIII as a novel isoform expressed in human macrophages and in human atherosclerotic plaques
Spread of extended-spectrum beta-lactamase producing Escherichia coli isolates in Swedish broilers mediated by an incI plasmid carrying blaCTX-M-1
Key aspects to consider when designing an IT-tool based on scoring rubrics to support formative assessment: an exploratory design-driven study
Why this thesis is needed. This thesis is motivated by the falling school results of Swedish 15-year-olds, a lack of IT tools in Swedish schools and a call for turning the theory on formative assessment into practice. Previous research that is used in the thesis. This thesis mainly builds on the research done by John Hattie which is presented in his book Visible Learning from 2009, Wiliam & Thompson's research on effective formative assessment from 2007, Pachler et al. research on formative e-assessment from 2010 and Panadero & Jonsson's research on scoring rubrics from 2013. Research question. What key aspects should be taken into consideration when designing and implementing an IT tool based on scoring rubrics which aims to support formative assessment according to the key strategies for effective formative assessment as identified by Wiliam & Thompson (2007)? Method. To answer this question I chose a qualitative approach of parallel paper prototyping where I iteratively exposed the design and my ideas during focus groups to teachers, a headmaster, employees at The Swedish National Agency for Education and high school students, followed by an evaluation of the key topics that surfaced during the focus groups. Results. The results consist of eight key aspects to take into consideration when designing and implementing such a tool. Discussion and future research. Finally I discuss the implications of my findings and present directions for future research which include the construction of the tool, further investigation of the key aspects identified in this study, identification of additional key aspects and more.Varför denna avhandling behövs. Denna avhandling motiveras av de fallande skolresultaten hos svenska 15-åringar, en brist på IT-verktyg i svenska skolor och ett rop efter att vända forskning inom formativ bedömning till praktik. Tidigare forskning som används. Denna avhandling bygger i huvudsak på forskningen av John Hattie som presenteras i hans bok Visible Learning från 2009, William & Thompsons forskning på effektiv formativ bedömning från 2007, Pachler et al. forskning på formativ e-bedömning från 2010 och Panadero & Jonssons forskning på betygsmatriser från 2013. Forskningsfråga. Vilka nyckelaspekter ska tas i åtanke vid utveckling av ett IT-verktyg baserat på betygsmatriser som stödjer formativ bedömning enligt de fem nyckelstrategierna för effektiv formativ bedömning som formulerats av Wiliam & Thompson (2007)? Metod. För att besvara denna fråga valdes en kvalitativ metod där parallell pappersprototypning användes under ett antal iterationer av fokusgrupper under vilka designen och tidigare diskussionpunkter diskuterades med lärare, en rektor, anställda vid Skolverket samt gymnasiestudenter. Fokusgrupperna följdes upp med en utvärdering av de största diskussionpunkterna som dök upp. Resultat. Resultaten består av åtta nyckelaspekter att ha i åtanke vid utveckling av ett sådant verktyg. Diskussion och framtida forskning. Slutligen diskuteras implikationerna av resultaten och direktioner för framtida forskning framförs. Dessa direktioner inkluderar utveckling av verktyget, vidare utredning av de nyckelaspekter som hittats i denna avhandling, identifikation av ytterligare nyckelaspekter och mer
A new method for ground vehicle access control and situation awareness : experiences from a real-life implementation at an airport
To improve safety in complex traffic situations, access control can be applied. This paper presents a generic vehicle access control method for improved situation awareness. The method concerns three main steps (i) zones definition (ii) rules to manage access and (iii) situation awareness based on realtime position monitoring. The proposed system consists of a server where the access zones and rules are stored and mobile units providing position data to the server and information to the driver. At the control center a client control unit is used to provide improved situation awareness by monitoring and visualizing the positions of the clients in the vehicles. The client in the control center is also utilized to give access to the clients in the vehicles that request access. The system has been demonstrated at an airport to grant access for ground vehicles to enter the runway and has since been developed into a commercial product by an industrial supplier. It was introduced at the World ATM Congress in Madrid in March of 2017. The server system is implemented as a cloud service in Microsoft Azure, the control client uses a WACOM CINTIQ touch screen computer for interaction and the vehicle clients are off-the-shelf Samsung Android units paired with Trimble R1GNSS receiver and 4G mobile communication between the server and the clients
Fracture-related mortality in southern Sweden : A multiple cause of death analysis, 1998-2014
PURPOSE: To assess fracture-related mortality among adults (aged ≥20years) in southern Sweden using multiple causes of death approach.METHODS: All death certificates (n=201 488) in adults recorded in the region of Skåne from 1998 to 2014 were examined. We identified fracture-related deaths and computed mortality rates by sex, age group, and fracture site. Temporal trends were evaluated using joinpoint regression and associated causes were identified by age- and sex-adjusted observed/expected ratios.RESULTS: Fractures were mentioned on 6 226 (3.1%) death certificates, with majority of these occurred among women (60%) and those aged≥80years (77%). While hip was the most common site overall (61% of all fracture-related deaths), skull was the most common site in people <60years (60% of all fracture-related deaths). Proportion of death certificates mentioning fracture was stable in women but increased by 0.4% (95% CI: 0.1 to 0.6) in men between 1998-2002 and 2010-2014. The mean age at death was higher in death certificates mentioning fracture than those without and this gap widened over time. The mean age-standardized fracture-related mortality rate was 18.8 (14.0) per 100 000 person-year in men (women) and declined by 1.5% (1.3%) per year during 1998-2014. Injuries (84.6%) and cardiovascular disorders (64.6%) were the most common comorbidities on death certificates mentioning fracture.CONCLUSIONS: Fracture is a contributing cause of death in more than 3% of all deaths in southern Sweden with hip in lead among older and skull fracture among younger people. There was a slight increase in proportion of deaths associated with fracture in men but not women during the study period
Fall-related mortality in southern Sweden : a multiple cause of death analysis, 1998-2014
OBJECTIVES: To investigate temporal trend in fall mortality among adults (aged ≥20 years) in southern Sweden using multiple cause of death data.METHODS: We examined all death certificates (DCs, n=2 01 488) in adults recorded in the Skåne region during 1998-2014. We identified all fall deaths using International Statistical Classification of Diseases (ICD)-10 codes (W00-W19) and calculated the mortality rates by age and sex. Temporal trends were evaluated using joinpoint regression and associated causes were identified by age-adjusted and sex-adjusted observed/expected ratios.RESULTS: Falls were mentioned on 1.0% and selected as underlying cause in 0.7% of all DCs, with the highest frequency among those aged ≥70 years. The majority (75.6%) of fall deaths were coded as unspecified fall (ICD-10 code: W19) followed by falling on or from stairs/steps (7.7%, ICD-10 code: W10) and other falls on the same level (6.3%, ICD-10 code: W18). The mean age at fall deaths increased from 77.5 years in 1998-2002 to 82.9 years in 2010-2014 while for other deaths it increased from 78.5 to 79.8 years over the same period. The overall mean age-standardised rate of fall mortality was 8.3 and 4.0 per 1 00 000 person-years in men and women, respectively, and increased by 1.7% per year in men and 0.8% per year in women during 1998-2014. Head injury and diseases of the circulatory system were recorded as contributing cause on 48.7% of fall deaths.CONCLUSIONS: There is an increasing trend of deaths due to falls in southern Sweden. Further investigations are required to explain this observation particularly among elderly men
Spread of extended-spectrum beta-lactamase producing Escherichia coli isolates in Swedish broilers mediated by an incI plasmid carrying blaCTX-M-1
BACKGROUND: The already high and increasing occurrence of extended-spectrum beta-lactamases (ESBL) producing Escherichia coli in European broiler populations is of concern due to the fact that third and fourth generation cephalosporins are deemed critically important in human medicine. In Sweden 34% of the broilers carry ESBL/pAmpC producing E. coli in their gut, despite the absence of a known selection pressure such as antimicrobial usages. The aim of the current study was to characterise a selection of E. coli strains carrying the bla(CTX-M-1), to determine if the spread was due to a specific clone. FINDINGS: Ten isolates carrying bla(CTX-M-1) from Swedish broilers belonged to eight different multi-locus sequence types with three isolates belonging to ST155. The ST155 isolates were identical as assessed by PFGE. The bla(CTX-M-1) was in all isolates carried on a plasmid of replicon type incI, which also transferred resistance to tetracycline and sulfamethoxazole. CONCLUSION: The occurrence of ESBL-producing E. coli in the Swedish broilers is not due to the emergence of a single clone, but rather the spread of a specific incI plasmid carrying bla(CTX-M-1)