Counting the number of enzymes immobilized onto a nanoparticle-coated electrode

To immobilize enzymes at the surface of a nanoparticle-based electrochemical sensor is a common method to construct biosensors for non-electroactive analytes. Studying the interactions between the enzymes and nanoparticle support is of great importance in optimizing the conditions for biosensor design. This can be achieved by using a combination of analytical methods to carefully characterize the enzyme nanoparticle coating at the sensor surface while studying the optimal conditions for enzyme immobilization. From this analytical approach, it was found that controlling the enzyme coverage to a monolayer was a key factor to significantly improve the temporal resolution of biosensors. However, these characterization methods involve both tedious methodologies and working with toxic cyanide solutions. Here we introduce a new analytical method that allows direct quantification of the number of immobilized enzymes (glucose oxidase) at the surface of a gold nanoparticle coated glassy carbon electrode. This was achieved by exploiting an electrochemical stripping method for the direct quantification of the density and size of gold nanoparticles coating the electrode surface and combining this information with quantification of fluorophore-labeled enzymes bound to the sensor surface after stripping off their nanoparticle support. This method is both significantly much faster compared to previously reported methods and with the advantage that this method presented is non-toxic

Lipocalin-2 is increased in progressive multiple sclerosis and inhibits remyelination

Objective: We aimed to examine the regulation of lipocalin-2 (LCN2) in multiple sclerosis (MS) and its potential functional relevance with regard to myelination and neurodegeneration. Methods: We determined LCN2 levels in 3 different studies: (1) in CSF and plasma from a case-control study comparing patients with MS (n = 147) with controls (n = 50) and patients with relapsing-remitting MS (n = 75) with patients with progressive MS (n = 72); (2) in CSF and brain tissue microdialysates from a case series of 7 patients with progressive MS; and (3) in CSF at baseline and 60 weeks after natalizumab treatment in a cohort study of 17 patients with progressive MS. Correlation to neurofilament light, a marker of neuroaxonal injury, was tested. The effect of LCN2 on myelination and neurodegeneration was studied in a rat in vitro neuroglial cell coculture model. Results: Intrathecal production of LCN2 was increased predominantly in patients with progressive MS (p < 0.005 vs relapsing-remitting MS) and displayed a positive correlation to neurofilament light (p = 0.005). Levels of LCN2 in brain microdialysates were severalfold higher than in the CSF, suggesting local production in progressive MS. Treatment with natalizumab in progressive MS reduced LCN2 levels an average of 13% (p < 0.0001). LCN2 was found to inhibit remyelination in a dose-dependent manner in vitro. Conclusions: LCN2 production is predominantly increased in progressive MS. Although this moderate increase does not support the use of LCN2 as a biomarker, the correlation to neurofilament light and the inhibitory effect on remyelination suggest that LCN2 might contribute to neurodegeneration through myelination-dependent pathways

Resursutvärdering av insatsmöjligheter : Huvudkulvertsystem vid SSAB EMEA, Luleå

SSAB EMEA is one of the world's most prominent industries in the steel manufacturing. In order to ensure continuous production of steel and an otherwise functioning operation some vital features must work. One of those vital features that affect all functions within the organization is the distribution of electrical energy. Below ground at SSAB EMEAs area there are cable culverts where power supply and control cables are located. Power supply cables provides processes and facilities in the area and control cable for controlling the manufacturing process.A fire in any part of these cable culverts would cause serious consequences from an economic perspective and may also result in serious injury or death.The work of this report has examined what SSAB EMEAs own organization can do in a fire incident in the cable culvert. It was necessary to find out what the internal emergency service could do in case of a fire incident. The division of electrical distribution at SSAB EMEA also has an important role in case of a fire incident because of their expert skills regarding electrical equipment.Four main issues were identified and became the basis for the further work.• Culvert design and its fire protection?• The proactive safety works in the organization in terms of material and education?• What is the knowledge in terms of safety behaviour in spaces with electrical installations of the staff at the internal fire department?• What procedures are there for the staff of electrical distribution to make the cables current less in a fire scenario?The methods used to make this resource assessment of the organization are largely based on site visits and interviews at both the department for distribution and on the internal emergency service.Initially it was considered important to get better insight in the two different departments. What resources had each department? What was their view of the issue and its problems? Several visits to the culvert system was carried out to see what physical conditions the facility was in terms of fire safety, accessibility, evacuation and similar.Discussions were held regarding the ability of the personnel at the fire department and an inventory of their equipment was conducted. Discussions and interviews became a foundation for what areas that should be further investigated in literature study. Great importance was considered on security issues and above all personal safety in case of emergency resource in spaces with high voltage installations. This led to an investigation with a number of different extinguishing methods and their advantages and disadvantages when used in high voltage installations.Regulations regarding BA-group were investigated in the report with respect to the resources of the organisation.Pre-planning processes is about the prevention of accidents as well as handle them safely and effectively. It all has a basis in the law lag (2003:778) om skydd mot olyckor.The law states that the facility owner or the holder of the business is required to prevent and mitigate such damage. A good pre-planning process is one way in the early stages to prevent and reduce such consequences. Pre-planning process involves many parts, it covers everything from collecting technical information about the object to risk analysis and exercises in action. The work culminates in operational plans with information regarding technical details of the object that serves the emergency service in case of an accident.Other organisations with cable culverts and even SSAB EMEA in Luleå has generally no set of procedures on how an fire fighting operation should be conducted in their own culvert system. Those responsible for each organisation meant that the way it should be done was entirely dependent on the situation.The discussion could be concluded that during a fire, it is important to be able to do as many of the cables current less to minimize the risks for rescue workers during an operation in the culvert. The opinions regarding strategies of fire fighting in the culvert system was based on the literature study as well as the organizations capacity in terms of manpower and equipment. It was confirmed that the strategies was different depending on where the fire would likely begin. If the fire would start in section T-EH it was considered most effective and safe to extinguish the fire by using the so-called fire-extinguishing grenades. In the sections T-EA and T-EB the recommendation was to make experiments of smoke gas evacuation. This could be done by filling the whole section with cold smoke and by pressurization try to evacuate the smoke gases at the escape route in the middle of the section. A successful evacuation of smoke gases as a result of pressurization could be the only way to make an acceptable environment for the fire fighters to go in to the culvert and extinguishing the fire. To suppress the actual fire it is suggested to use either dry chemical powder or water spray.Validerat; 20121120 (global_studentproject_submitter

Studier av biologin vid intratekal behandling vid progressiv MS

Background: Multiple Sclerosis (MS) is a chronic, inflammatory, autoimmune disease, affecting the central nervous system (CNS). About 85% of afflicted present with a relapsing-remitting form of the disease (RRMS), for which a breakthrough in treatment was made in 2008 with rituximab, an antibody directed towards CD20, a surface antigen on B-cells. These findings also contributed to cementing the importance of the B-cell’s role in MS pathophysiology. However, MS also exist as a progressive phenotype, affecting most MS patients either from onset or after a transition from RRMS, and for progressive MS the same treatment effect of anti-CD20 has not been observed. Still, studies have found follicle-like structures containing B-cells in meninges and subarachnoid space of the cortex in progressive MS brains, supporting the involvement of B-cells. Evidence also support the existence of a chronic, low-grade inflammatory process compartmentalised within the CNS that correlates with the progressive phase of MS, which may present a treatment barrier towards anti-CD20. Peripherally administrated therapeutic antibodies cross the intact blood-brain barrier with low efficiency with only 0.1-0.5% of the plasma concentration occurring in the cerebrospinal fluid (CSF). Intrathecal (IT) administration circumvents the blood-brain barrier, presenting an opportunity to better target the CNS B-cells. Aims: To evaluate the safety and feasibility of intrathecal anti-CD20 therapy with rituximab in progressive MS, its effect on disease progression through clinical parameters, and impact on biomarkers in CSF. Furthermore, this thesis aimed to evaluate the effect on biomarkers representative of cell injury related to insertion of a ventricular catheter for drug administration and to examine the interstitial milieu in the brain through microdialysis (MD). Methods: The thesis is based on the open-label, phase IIb, multicentre clinical trial Intrathecal Treatment Trial in Progressive Multiple Sclerosis (ITT-PMS; EudraCT 2008-002626-11), in which 23 participants received IT treatment with rituximab, and the extended follow-up study, ITT-PMS extension (EudraCT 2012-000721-53). All participants received a ventricular catheter and an Ommaya reservoir for drug administration through a neurosurgical procedure, and 10 participants received a MD catheter in parallel to the ventricular catheter for 10 days. The treatment effect was evaluated by regular clinical evaluations and analyses of CSF. The clinical outcome was evaluated through walking and upper-limb function tests, and by clinical evaluation scales. Levels of selected CSF biomarkers were analysed from the same time-points as the clinical evaluations. Results: After the completion of the extension trial, one clinical parameter (cognitive performance) showed improvement but could most likely be explained by a learning effect. Worsening of walking speed was observed, while the remaining clinical parameters showed no change. Two severe adverse events occurred in the form of low-virulent bacterial meningitis caused by Propionibacterium, but both were treated effectively with antibiotics without residual symptoms. A ‘spike’ was noticed in the level of lumbar CSF neurofilament light (NFL) following surgery but returned to pre-surgery baseline within 6-12 months. No change was observed for any of the other lumbar CSF biomarkers. No meaningful correlation of protein levels was observed when comparing MD samples, ventricular CSF, and lumbar CSF. Conclusions: Intrathecal treatment through intraventricular administration was well tolerated but not without risks. A continued progression was observed in gait impairment. The insertion of the ventricular catheter caused white matter injury, measured through an increase in NFL in lumbar CSF, in direct association with the surgical procedure. No impact was observed on other CSF biomarkers. There was a poor correlation between different CNS compartments regarding protein levels, arguing for caution in drawing conclusions about brain pathophysiology from lumbar CSF samples.Ny lokal: På spikbladet anges tidigare fastslagna lokal. </p

Viral marknadsföring för MMO-spel : Att marknadsföra spel som Dreamlords: The Reawakening

Detta examensarbete består av skapandet samt det praktiskatillämpandet av en metod, som har syftet att med hjälp av viralmarknadsföring få in nya spelare till ett massivt onlinespel1.Syftet med detta examensarbete är att skapa en bättre uppfattningom vad viral marknadsföring är för något, men också hur man kananvända den i marknadsföringssyfte.Metoden går ut på att skapa tre olika faser, även kalladetillämpningsfaser, som alla har sitt eget syfte och sedan tillämpadessa fasers olika beståndsdelar för att sedan uppskatta ett resultatutifrån detta.Om man genom denna metod förbereder och förbättrar speletscommunity tillräckligt bra, är förhoppningen att de potentiella spelarnasom når communityn ska stanna kvar och bli faktiska spelare. För attfå potentiella spelare att nå spelets community krävs det att speletsrepresentation, i detta fall spelets hemsida och communityforum, ärtillräckligt tilltalande och informativ. För att dessa två delar ska spelanågon roll, krävs det något sätt att få in potentiella spelare till speletshemsida. Detta gör man med viral marknadsföring. Lyckas alla dessadelar, har metoden fungerat och nått ett framgångsrikt resultat.Då området kring examensarbetet är relativt nytt, finns därför brist på detaljspecifierade referenser i examensarbetet.Dreamlords: The Reawakenin

Ambulanssjuksköterskans upplevelser - från utlarmning till ankomst till ett allvarligt skadat eller sjukt barn : en kvalitativ intervjustudie

Barn är inte små vuxna. Omhändertagandet av barn inom sjukvården skiljer sig på många sätt gentemot vården av vuxna. Dels skiljer sig barns anatomi och fysiologi mot vuxna. Dessutom finns det emotionella perspektiv för vårdpersonal, då vårdpersonal ofta blir mer emotionellt berörda av att omhänderta barn. Barnets föräldrar som ofta är stressade och rädda, bör även de få en god och trygg omvårdnad. Många ambulanssjuksköterskor tycker att omhändertagandet av barn är det svåraste i yrket. Både för att barn upplevs som emotionellt påfrestande att omhänderta samt att barn sällan är svårt sjuka eller allvarligt skadade, varför ambulanssjuksköterskan kan uppleva en ovana och osäkerhet. Då ambulanssjuksköterskan får larm påbörjas förberedelsefasen och förberedelsefasen pågår till att ambulansen ankommer till patienten. Författarna finner att ambulanssjuksköterskors upplevelse av att omhänderta barn är någonting väl studerat, dock finner författarna inga studier gällande ambulanssjuksköterskans upplevelser av förberedelsefasen. Syftet var attI arbetet valdes en kvalitativ deskriptiv design med Ambulanssjuksköterskor omhändertar sällan allvarligt skadade eller svårt sjuka barn. Det gjorde att ambulanssjuksköterskor kände stress, rädsla och i vissa fall skräck då de fick larm som indikerade på ett allvarligt skadat eller svårt sjukt barn. Varför larm om barn upplevdes annorlunda än vuxna var dels för att det framkallade en starkare emotionell respons, men även att barn var mindre i storlek, en ovana bland ambulanssjuksköterskor gällande att omhänderta barn, samt annorlunda läkemedelsdoser gentemot vuxna. Ambulanssjuksköterskorna i studien upplevde att de behövde fler resurser när de omhändertar barn till skillnad mot vuxna. Eftersom föräldrarna behövde stöttning och omvårdnad då deras barn var svårt sjukt eller allvarligt skadat. Att ge föräldrarna tillräcklig uppmärksamhet med en ambulansbesättning upplevdes som mycket svårt, varför fler resurser behövdes. Ambulanssjuksköterskor upplevde överlag att de behövde mer utbildning i omhändertagandet av svårt sjuka eller allvarligt skadade barn. I enlighet med ambulanssjuksköterskornas upplevelser, inkluderade studier och litteraturen, behövdes ytterligare utbildning inom specifikt det akuta omhändertagandet av barn. Även fler resurser ansågs nödvändiga vid larm om barn. Detta för tillsammans med ytterligare utbildning och erfarenhet - ge ambulanssjuksköterskan möjligheten att bli tryggare i sina förberedelser samt i sitt omhändertagande av barn och dennes anhöriga.Children are not small adults. Caring for children in healthcare differs from taking care of adults in many aspects. For example children have a different anatomy and physiology compared to adults and this must be taken in to consideration. Another perspective is the fact that healthcare professionals often become more emotionally involved when caring for a child. The parents of the child, who are often stressed and afraid, should also be provided with safe and good care. A large part of the ambulance nurses feel that the caring of children is the hardest part in their profession. This is due to both the general feeling of children being emotionally challenging to care for and the fact that children are so rarely critically ill or injured. This combined can make the ambulance nurse feel unused to the task and insecure on how to approach it. When the ambulance nurse is reached by the alarm the preparing phase initiates. This phase is ongoing until the ambulance arrives at the patient. The authors find that ambulance nurses experiences of caring for children is well studied. However, the authors find no studies on ambulance nurses experiences of the preparation phase. The aim of this study is to enlighten the ambulance nurses ́ experiences of the preparation phase – from the time when receiving the alarm until arriving to a severely injured or a cricitcally ill child. The study has been conducted through a qualitative approach with semi structured interviews. Eight ambulance nurses participated in the study. To be included they had to have experience of taking care of at least one critically ill or injured child where it was clear from the alarm that the child was critically ill or severely wounded. The interviews were then analyzed with a qualitative content analysis. The studys result showed that ambulance nurses seldom take care of severly injured or critically ill children. This lead to ambulance nurses experiencing stress, fear and in certain cases horror when encountering an alarm indicating that it is about a critically ill or severly injured child. The reasons why ambulance nurses experienced these alarms concerning children differently - compared to alarms concerning adults were: a stronger emotional response, children are smaller in size, an unacustomedness among ambulance nurses regarding taking care of critically ill or severly injured children and ultimately different doses regarding medicine as regards to adults. Ambulance nurses in the study experienced a need for more human resources when taking care of a child as regards to an adult. This because the childs parents needed support and care when their child is critically illa or severly injured. Providing the parents with enough attention with only one ambulance crew is difficult, which is why more human resources were needed. Ambulance nurses described a general need for more education regarding the care of critically ill or severly injured children. In accordance with ambulance nurces experiences, included studies and the litterature –more education in specifically the emergency treatment of children was needed. Aswell was the need for more human resources when it came to alarms regarding children. This together with more education and experience, could give the ambulance nurse the opportunity to become more confident in their preparations and care of children and their relatives

"Jag är nöjd med allt fröknar bestämmer!” : En studie kring elevers tankar och upplevelser om elevinflytande

Studien handlar om elevers tankar och upplevelser kring elevinflytande på fritidshem. Syftet är att se hur elevers tankar och upplevelser kommer till uttryck i verksamheten. Metoderna som har används i undersökningen är samtalspromenader där elevers tankar och upplevelser ska lyftas fram. Därför har vi valt demokrati och elevinflytande som argumenterande forskning för vår studie. Vårt teoretiska perspektiv är barns perspektiv som används för att se elevernas erfarenheter, uppfattningar och förståelse av sin livsvärld. I studien framgår det att eleverna har inflytande när det gäller vissa saker på fritidshemmet. Eleverna har även en viss förståelse kring begreppet inflytande och fritidslärarna har goda möjligheter att bygga vidare på detta utifrån elevernas perspektiv

Avtalsslutande genom internet : En genomgång av avtalsrätt i förhållande till internet samt online auktioner

Tekniken utvecklas mer för varje dag och i takt med detta så ingås avtal allt mer i elektronisk form. I takt med teknologisk framgång uppstår det dock nya problem. Frågan är om den åldrande regleringen i avtalslagen för traditionella avtal kan appliceras på dessa nya problem i förhållande till elektroniska avtal. Syftet med arbetet har varit att fastställa gällande rätt för elektroniska avtal. För att kunna göra detta har en redogörelse av innehållet i traditionell avtalsrätt gjorts. Därefter följer en analys samt en jämförelse av likheter och skillnader gentemot varandra. Detta arbete har använt traditionell juridisk metod för att besvara syftet. Resultatet av arbetet är att avtalslagens allmänna karaktär gör att lagen är applicerbar på elektroniska avtal samt internetauktioner. Det finns dock viktiga skillnader som med hjälp av praxis kommer klargöras. Den teknologiska utvecklingen i form av till exempel elektroniska signaturer har sett till att det nu är säkrare än någonsin att ingå elektroniska avtal