Complications after total hip arthroplasty : register-based studies on surgical approach and infections

Background: The often excellent outcome of total hip arthroplasty (THA) is sometimes compromised by prosthesis related complications. There is an ongoing debate regarding the effect of surgical approach on prosthesis related complications and patient reported outcome. The incidence of periprosthetic joint infection (PJI) following THA in Sweden is unknown as well as the completeness of the Swedish Hip Arthroplasty Register (SHAR) to record reoperations due to infection. Methods: Study 1 and 2 were solely based on data from the SHAR. In study 1, the risk of revision due to infection, dislocation and loosening of the prosthesis was compared between the posterior and the direct lateral approach for the most commonly used cemented THAs. Relative risks were calculated with a Cox regression analysis with respect to known confounders. In study 2, Patient Reported Outcome Measures (PROMs) were compared between patients that had received a THA for osteoarthritis by either the posterior or direct lateral approach. The postoperative pain, satisfaction and health related quality of life were compared by Chi2-test, T-test and multivariate regression analysis. In study 3 and 4 a large cohort of patients that had undergone primary THA were selected from the SHAR and their antibiotic consumption was extracted from the Swedish Prescribed Drugs Register (SPDR). For patients with ≥28 days of antibiotic treatment within 2 years after the surgery a medical records review was conducted. From this survey the cumulative incidence of early and delayed PJI was calculated. The number of reoperated THAs due to infection were compared with the SHAR reoperation database determining the completeness of the register. In Study 5, PJI-cases were compared to matched controls regarding known and suspected risk factors from the SHAR and the National Patient Register and analyzed by multivariate regression analysis. Results: The posterior approach lead to superior PROM values for patients with OA and lead to less aseptic loosening but increased risk of dislocation in some of the investigated all cemented THAs. The cumulative incidence of early and delayed PJIs in Sweden for the study period was 0.9 % and the trend was slightly increasing. The registration completeness of reoperations due to infection in the SHAR was 67 %. Patient comorbidity had more influence than surgical or environmental factors on PJI risk. Discussion: The discussion regarding the advantages of different surgical approaches in THA is not ended by these studies, but it seems that the surgical approach has influence on the outcome. The surgical approach should therefore perhaps be a part of the preoperative planning just as the method of fixation and implant and related to both patient factors and the reason for the THA. In order to reduce the infection incidence it is important to define the magnitude of the incidence. This study presents a novel approach to incidence estimation and evaluates the SHAR reoperation database which has been the most commonly used measure of infections after THA in Sweden. As patient comorbidity seems to be the most important factor on a population level it will be difficult to further decrease the incidence

Эволюция менталитета российской интеллегенции во времена революционных кризисов начала ХХ века

Материалы II междунар. науч. конф., 23-24 мая 2001 г

Widespread horse-based mobility arose around 2200 BCE in Eurasia.

Horses revolutionized human history with fast mobility1. However, the timeline between their domestication and their widespread integration as a means of transport remains contentious2-4. Here we assemble a collection of 475 ancient horse genomes to assess the period when these animals were first reshaped by human agency in Eurasia. We find that reproductive control of the modern domestic lineage emerged around 2200 BCE, through close-kin mating and shortened generation times. Reproductive control emerged following a severe domestication bottleneck starting no earlier than approximately 2700 BCE, and coincided with a sudden expansion across Eurasia that ultimately resulted in the replacement of nearly every local horse lineage. This expansion marked the rise of widespread horse-based mobility in human history, which refutes the commonly held narrative of large horse herds accompanying the massive migration of steppe peoples across Europe around 3000 BCE and earlier3,5. Finally, we detect significantly shortened generation times at Botai around 3500 BCE, a settlement from central Asia associated with corrals and a subsistence economy centred on horses6,7. This supports local horse husbandry before the rise of modern domestic bloodlines

Evaluating Multi-Uav System with Text to Spech for Sitational Awarness and Workload

With improvements to miniaturization technologies, the ratio between operators required per UAV has become increasingly smaller at the cost of increased workload. Workload is an important factor to consider when designing the multi-UAV systems of tomorrow as too much workload may decrease an operator's performance. This study proposes the use of text to speech combined with an emphasis on a single screen design as a way of improving situational awareness and perceived workload. A controlled experiment consisting of 18 participants was conducted inside a simulator. Their situational awareness and perceived workload was measured using SAGAT and NASA-TLX respectively. The results show that the use of text to speech lead to a decrease in situational awareness for all elements inside the graphical user interface that were not directly handled by a text to speech event. All of the NASA-TLX measurements showed an improvement in perceived workload except for physical demand. Overall an improvement of perceived workload was observed when text to speech was in use

OTT Videomätning

Video streaming has become more and more popular in recent years. New protocols have emerged to improve the availability and simplify usage.The purpose of this thesis work is to measure video player's performance and make a model of the player's behavior. The intent of the model is to aid understanding of the problems with video playback, such as low video quality or interruption, in order to ease troubleshooting. To create a model video players were observed and measurement data, called metrics, was collected when they were playing video during different conditions. The metrics were found in the source code of the video player and with the help from the official documentation. Tests were performed with the official video player for three popular protocols: HTTP Live Streaming created by Apple, HTTP Dynamic Streaming created by Adobe and Microsoft Smooth Streaming. Characteristic and pattern were seen in the test results.The three examined protocols use adaptive bitrate to adjust the video quality according to the circumstances. Examples of circumstances can be an unstable network connection or when a too slow processor is being used. In the tests, parameters such as network bandwidth, video size and processor usage were tested in the web browser Safari.This thesis work suggests a simplified and general model for the three examined protocols aimed for testing the network connection when streaming video.Validerat; 20140122 (global_studentproject_submitter

Databasmigration från SQL Server till Amazon Redshift

Growing databases create a need for improved storage and analysis solutions. One company with that need is Bring SCM, who have been looking for a solution to better analyze their business data, which is currently hosted on a SQL Server-database by Elastic Mobile. To improve this solution, this paper will examine a data warehouse solution to the problem, specifically using the cloud-based Amazon Redshift data warehouse. Additionally, Amazon’s Database Migration Service will be examined as an alternative to the current migration solution. For Database Migration Service, both the migration of the full database as well as the continuous data replication are tested. Redshift is tested based on performance for eight SQL statements that Bring SCM currently use in their work. This is performed both on a storage-optimized cluster and a computation-optimized one. Finally, the costs of running the different clusters are used to evaluate the cost-effectiveness of the solutions. Database Migration Service showed great potential compared to the current migration solution, and the storage-optimized Redshift-cluster gave both good performance and cost-efficiency. The computation-optimized cluster performed worse than expected, especially in relation to the cost. Redshift and Database Migration Service are very promising alternatives to the current SQL Server-solution for analysis purposes, but when implementing such a system, consideration should be taken regarding optimizing the data structure for data warehouse use

Pojkars avhopp inom föreningsfotboll : En studie av påverkansfaktorer i Västerbotten

The purpose of the study was to increase knowledge about youth football in relation to reasons for beginning to participate, and reasons behind early drop-out. Another purpose of the study was to investigate potential preventive methods in order to counterwork drop-out rates among boys. A district association of Swedish football, Västerbottens Fotbollförbund, was keen to discover these reasons and preventive methods in order to develop more interest throughout their football-district and prevent early drop-out rates among boys. The study was designed using a questionnaire in which 27 boys aged13-17 in Skellefteå municipality answered a questionnaire with open-ended questions regarding the purpose of the study. The results indicate that the opportunity to participate in more than one sport is problematic and that the boys valued belonging and team spirit. Furthermore, the boys proposedcreating sustainable opportunities to participate in more than one sport and to focus more on having fun during practice in order to counter-work drop-out rates. A conclusion drawn from the results of the study is that the different sports within Skellefteå municipality are in need of better cooperation. Another conclusion is that the boys expressed a desire for more and different levels of ambition to reduce drop-out rates. Creating different prioritization within the different levels of ambition was alsosuggested by the boys themselves. For example, to prioritize belonging and having fun in clubs with lower levels of ambition. To counterwork early drop-out rates there needs to be conditions making it possible to participate in more than one sport. Furthermore, clubs from different sports in the municipality are proposed to discuss the topic of drop-out and preventive measures suggested by the boys in the study

Sustainable mutual funds : A possible attitude-behaviour gap and the reasons behind

Bakgrund: I Sverige har intresset för att investera i hållbara fonder ökat rejält de senaste åren och med detta följer också en stor ökning i utbudet av hållbara fonder. Känt sedan tidigare är också att det råder en definitionsproblematik på ämnet som adderar komplexitet till marknaden, detta då hållbarhet i sig är svårdefinierat. Indikationer visar att det kan råda en skillnad mellan andelen människor som är intresserade av att investera hållbart och de som faktiskt gör det. Syfte: Syftet med studien är att slå fast huruvida det råder ett attitude-behaviour gap på marknaden för hållbara fonder. Vidare ämnar uppsatsen att uppskatta storleken på fondförmögenheten som finns i svenska hållbara fonder, detta för att få en bättre bild av marknaden och dess omfång. Till sist vill uppsatsförfattarna på villkoret att det råder ett attitude-behaviour gap undersöka de faktorer som kan tänkas föranleda det. Genomförande: För att kunna genomföra studien och besvara dess frågeställningar har två kvantitativa samt en kvalitativ metod använts. De kvantitativa delarna har genomförts med dels en enkät för att slå fast huruvida det finns ett attitude-behaviour gap samt databaser med fonddata där syftet har varit att slå fast mängden kapital som finns allokerat till svenska hållbara fonder. Den kvalitativa delen har genomförts med hjälp av semistrukturerade-intervjuer med främst privatpersoner men också en expert på området. Slutsats: Studien har slagit fast att det råder ett attitude-behaviour gap på svenska marknaden för hållbara fonder. Vidare har slutsatsen dragits att det ej går att fastslå mängden kapital placerat i svenska hållbara fonder, detta med motiveringen att definitionsproblematiken och brist på vedertagna tredjepartsmärkningar gör det alltför osäkert. Slutligen har studien kommit fram till en rad olika faktorer som ligger till grund för attitude-behaviour gapet, bland dessa framträder oro kring avkastning, definitionsproblematik, kunskap och information som de mest avgörande.Background: The interest in sustainable mutual funds and the supply of them has rapidly grown in Sweden during the last years. It is previously known that there is a problem with the definition of what a sustainable mutual fund is, which adds a layer of complexity to the market. Indications shows that there might be a discrepancy between the number of people that are interested in sustainable mutual funds and those who buys them. Purpose: The aim with this study is to determine whether an attitude-behaviour gap exists on the market for sustainable mutual funds. Furthermore, the study intends to estimate the amount of capital invested in the Swedish market for sustainable funds, that is to broader the perspective of the market and its size. Finally, if there is an existing attitude- behaviour gap, the authors want to examine the factors behind the gap. Completion: To be able to carry out the study, both quantitative and qualitative methods have been used. The quantitative parts were made with both a survey to determine whether there is an attitude-behaviour gap and data collection concerning the amount of capital allocated to Swedish sustainable mutual funds. The qualitative part has been carried out with the help of semi-structured interviews with mainly private savers but also an expert in the field. Conclusion: The study has established that there is an attitude-behaviour gap in the Swedish market for sustainable funds. Furthermore, the conclusion has been drawn that it is not possible to determine the amount of capital invested in Swedish sustainable mutual funds, the reason being that the definition problem and the lack of accepted third- party labels make it too uncertain. Finally, the study has come up with several different factors that form the underlying reasons of the attitude behaviour gap, concerns about yield, definition problems, knowledge and information as the most crucial

Design of cooling system for an electrified all-terrain vehicle

In this thesis, operating modes and different concepts have been developed for a cooling system of a hybrid driveline. The project was carried out for BAE system Hägglunds in Örnsködsvik. Since 2001, the company produces a tracked vehicle called BvS10 that is primarily used for military purposes. In this project a cooling system for a new, electrified concept vehicle based on the BvS10 vehicle, called BvS15, was created. Electrified and hybrid vehicles became a necessity for BAE Systems Hägglunds due to major developments in electric components, and to be able to compete with other companies in this area.  A component list was created, all components and its specifics were gathered in an Excel document. From this point in the project different concepts and operating modes could be tested on the cooling system. Three different concepts were created with the same operating modes, the difference between the concepts was the placement of the components in the schematic layouts. The concepts each have their pros and cons, mainly regarding size of cooler and manufacturing difficulties, but also dimensioning of components in the circuits.  The result of this project is three concepts of a cooling system for a hybrid driveline. All concepts are considered feasible, what is used in the end depends on what BAE Systems Hägglunds prioritizes. The results can be used in studies regarding future tracked vehicles.I detta examensarbete har koncept och driftfall för en ny hybrid-drivlinas kylsystem tagits fram. Projektet utfördes för BAE Systems Hägglunds i Örnsköldsvik. Sedan 2001 har BvS10 varit en bandvagn som BAE System Hägglunds tillverkar för bland annat militärt bruk. I detta projekt har ett kylsystem för en elektrifierad konceptvagn Bvs15, som är baserad på BvS10 utvecklats. Elektrifierad och hybrid-drivlinor blev en nödvändighet för BAE Systems Hägglunds på grund avstora utvecklingarna inom elektrifierade komponenter, och eftersom man vill kunna konkurrera med andra företag inom området. En komponentlista skapades där alla komponenter och deras specifikationer samlades i ett Excel dokument. Från detta läge i projektet kunde test av driftfall och olika koncept på kylsystemet utföras. Det skapades tre olika koncept med samma driftfall, men med olika placeringar av komponenter i de schematiska layouterna. Koncepten har alla sina för- och nackdelar, främst i storleken av kylarpacket och tillverkningskomplexitet, men också i dimensioneringen av komponenter i kretsarna. Resultatet av detta projekt är tre koncept för ett kylsystem till en hybriddrivlina. Samtliga koncept anses genomförbara och vad som används i slutändan beror på vad BAE Systems Hägglunds prioriterar. Resultaten kan användas i en förstudie om framtida bandvagnar