Synchronization of streamed audio between multiple playback devices over an unmanaged IP network

When designing and implementing a prototype supporting inter-destination media synchronization – synchronized playback between multiple devices receiving the same stream – there are a lot of aspects that need to be considered, especially when working with unmanaged networks. Not only is a proper streaming protocol essential, but also a way to obtain and maintain the synchronization of the clocks of the devices. The thesis had a few constraints, namely that the server producing the stream should be written for the .NET-platform and that the clients receiving it should be using the media framework GStreamer. This framework provides methods for both achieving synchronization as well as resynchronization. As the provided resynchro- nization methods introduced distortions in the audio, an alternative method was implemented. This method focused on minimizing the distortions, thus maintain- ing a smooth playback. After the prototype had been implemented, it was tested to see how well it performed under the influence of packet loss and delay. The accuracy of the synchronization was also tested under optimal conditions using two different time synchronization protocols. What could be concluded from this was that a good synchronization could be maintained on unloaded networks using the proposed method, but when introducing delay the prototype struggled more. This was mainly due to the usage of the Network Time Protocol (NTP), which is known to perform badly on networks with asymmetric paths.When working with synchronized playback it is not enough just obtain- ing it – it also needs to be maintained. Implementing a prototype thus involves many parts ranging from choosing a proper streaming protocol, to handling glitch free resynchronization of audio. Synchronization between multiple speakers has a wide area of application, ranging from home entertainment solutions to big malls where announcements should appear synchronized over the entire perimeter. In order to achieve this, two main parts are involved: the streaming of the audio, and the actual synchronization. The streaming itself poses problems mostly since the prototype should not only work on dedicated networks, but rather on all kinds, such as the Internet. As the information over these networks are transmitted in packets, and the path from source to destination crosses many sub networks, the packets may be delayed or even lost. This may create an audible distortion in the playback. The next part is the synchronization. This is most easily achieved by putting a time on each packet stating when in the future it should be played out. If then all receivers play it back at the specified time, synchronization is achieved. This however requires that all the receivers share the idea of when a specific time is – the clocks at all the receivers must be synchronized. By using existing software and hardware solutions, such as the Network Time Protocol (NTP) or the Precision Time Protocol (PTP), this can be accomplished. The accuracy of the synchronization is therefore partly dependent on how well these solutions work. Another valid aspect is how accurate the synchronization must be for the sound to be perceived as synchronized by humans. This is usually in the range of a few tens of milliseconds to five milliseconds depending on the sound. When a global time has been distributed to all receivers, matters get more complicated as there is more than one clock to consider at each receiver. Apart from the previously mentioned clock, now called the ’system clock’, there is also an audio clock, which is a hardware clock positioned on the sound card. This audio clock decides the rate at which media is played out. Altering the system clock to synchronize it to a common time is one thing, but altering the audio clock while media is being played will inevitably mean a jump in the playback, and thus a distortion. Although an initial synchronization can be achieved, the two clocks will over time tick in slightly different pace, thus drifting away from each other. This creates a need for the audio clock to continuously correct itself to follow the system clock. In the media framework GStreamer, used for handling the media at the re- ceivers, two alternatives to solve the correction problem were available. Quick evaluations of these two methods however showed that either audible glitches or ’oscillations’ occurred in the sound, when the clocks were corrected. A new method, which basically combines the two existing, was therefore implemented. With this method the audio clock is continuously corrected, but in a smaller and less aggressive way. Listening tests revealed much smaller, often not audible, distortions, while the synchronization performance was at par with the existing methods. More thorough testing showed that the synchronization over networks with light traffic was in the microsecond-range, thus far below the threshold of what will appear as synchronized. During worse conditions – simulated hostile environments – the synchronization quickly reached unacceptable levels though. This was due to the previously mentioned NTP, and not the implemented method on the other hand

The Levity of Homogenisation of Taste - A Critical Inquiry into the Standardisation Construct

For decades, Theodore Levitt's notion of the homogenisation of consumer taste, as a consequence of globalisation, has been used in the marketing literature to legitimise standardisation as global strategy. Levitt's notion of homogenisation of taste refers to a worldwide desire for modern, low priced, world-standard and dependable products from the modern, and primarily western, world. Homogenisation of taste also presupposes a homogenisation of the meanings assigned to products and a view of the customers as passive recipients of promotional activity. The purpose of the thesis is to contribute to the understanding of the global corporation's role as an agent of homogenisation of taste, through a critical investigation of marketing guru Theodore Levitt’s theory in practice, regarding customers as passive recipients of promotional activities. The thought that meanings of modern, low priced, world-standard, and dependable products can be standardised in promotional activities are further investigated in view of that meanings are created in organised forms of social interaction in individual specific contexts. This is pursued by conducting a qualitative case study of how the promotion of standardised products is perceived by customers in a recently modernised market. In order to facilitate the comparison between corporate promotion and customer perceptions, the corporation's perception of the modern customer is in particularly investigated. The customers' perceptions are examined through qualitative interviews and observations of products in a home environment. In a joint analysis the differences of corporate and customers’ perceptions are singled out and discussed. Our study proposes that the corporation’s role as an agent of homogenisation of taste is limited to the moment of purchase. After purchase the customers seemed to decommodify and recontextualise the products, thereby assigning them other meanings than the ones promoted by the corporation. We found that this was not at least performed in order to handle the uniformity of the standardised products. Hence, our main conclusion is that customers are not passively receiving and accepting promotional activity. Therefore, a more careful usage of homogenisation of taste as legitimisation of the standardisation construct in the marketing literature is suggested

Kritisk öfversigt af Finlands Fisk-fauna

Akademisk afhandling.Mode of access: Internet

The provision of epilepsy care across Europe 2017 : a 17-year follow-up survey

OBJECTIVE: To assess the resources available in the provision of epilepsy care across Europe and the developments since the International League Against Epilepsy (ILAE) survey published in 2003 (data collected in 2000).METHODS: An updated online version of the European Epilepsy Services Inventory was distributed to all European chapters of the ILAE (N = 47) and responses were obtained from 33 chapters (response rate 70%). To assess trends and allow comparisons with the survey published in 2003, the responding countries were divided into 4 groups (Western, Central, Southern, and Eastern). Responses from European Union (EU) member states are reported as a subgroup (N = 23), since the current survey is a part of the EU‐funded European Study on the Burden and Care of Epilepsy (ESBACE, www.esbace.eu).RESULTS: The total number of physicians involved in epilepsy care had increased since 2000, with the largest increase seen for neurologists. The gap between the best‐ and the least‐provided areas with regard to the competence of the providers had diminished. However, the density of comprehensive multidisciplinary epilepsy teams had not changed to any greater degree. The main problems reported by the chapters were to a large extent the same as in 2000 and included lack of specialists and specialist care, lack or underuse of epilepsy surgery, and problems regarding financing and resource allocation. Several chapters also highlighted problems with healthcare structure and organization.SIGNIFICANCE: Although there have been some improvements concerning the availability of care for people with epilepsy in Europe over the last 17 years, there are still a number of problem areas with little improvement or where there are important regional differences.European Union (Directorate General for Health and Food safety), Grant/Award Number: 2014/1/1995648peer-reviewe

Asymmetric Inheritance of Aggregated Proteins and Age Reset in Yeast Are Regulated by Vac17-Dependent Vacuolar Functions

SummaryAge can be reset during mitosis in both yeast and stem cells to generate a young daughter cell from an aged and deteriorated one. This phenomenon requires asymmetry-generating genes (AGGs) that govern the asymmetrical inheritance of aggregated proteins. Using a genome-wide imaging screen to identify AGGs in Saccharomyces cerevisiae, we discovered a previously unknown role for endocytosis, vacuole fusion, and the myosin-dependent adaptor protein Vac17 in asymmetrical inheritance of misfolded proteins. Overproduction of Vac17 increases deposition of aggregates into cytoprotective vacuole-associated sites, counteracts age-related breakdown of endocytosis and vacuole integrity, and extends replicative lifespan. The link between damage asymmetry and vesicle trafficking can be explained by a direct interaction between aggregates and vesicles. We also show that the protein disaggregase Hsp104 interacts physically with endocytic vesicle-associated proteins, such as the dynamin-like protein, Vps1, which was also shown to be required for Vac17-dependent sequestration of protein aggregates. These data demonstrate that two physiognomies of aging—reduced endocytosis and protein aggregation—are interconnected and regulated by Vac17

Outcome in patients perceived as receiving excessive care across different ethical climates : a prospective study in 68 intensive care units in Europe and the USA

Whether the quality of the ethical climate in the intensive care unit (ICU) improves the identification of patients receiving excessive care and affects patient outcomes is unknown. In this prospective observational study, perceptions of excessive care (PECs) by clinicians working in 68 ICUs in Europe and the USA were collected daily during a 28-day period. The quality of the ethical climate in the ICUs was assessed via a validated questionnaire. We compared the combined endpoint (death, not at home or poor quality of life at 1 year) of patients with PECs and the time from PECs until written treatment-limitation decisions (TLDs) and death across the four climates defined via cluster analysis. Of the 4747 eligible clinicians, 2992 (63%) evaluated the ethical climate in their ICU. Of the 321 and 623 patients not admitted for monitoring only in ICUs with a good (n = 12, 18%) and poor (n = 24, 35%) climate, 36 (11%) and 74 (12%), respectively were identified with PECs by at least two clinicians. Of the 35 and 71 identified patients with an available combined endpoint, 100% (95% CI 90.0-1.00) and 85.9% (75.4-92.0) (P = 0.02) attained that endpoint. The risk of death (HR 1.88, 95% CI 1.20-2.92) or receiving a written TLD (HR 2.32, CI 1.11-4.85) in patients with PECs by at least two clinicians was higher in ICUs with a good climate than in those with a poor one. The differences between ICUs with an average climate, with (n = 12, 18%) or without (n = 20, 29%) nursing involvement at the end of life, and ICUs with a poor climate were less obvious but still in favour of the former. Enhancing the quality of the ethical climate in the ICU may improve both the identification of patients receiving excessive care and the decision-making process at the end of life

Ethical climate and intention to leave among critical care clinicians : an observational study in 68 intensive care units across Europe and the United States

PurposeApart from organizational issues, quality of inter-professional collaboration during ethical decision-making may affect the intention to leave one's job. To determine whether ethical climate is associated with the intention to leave after adjustment for country, ICU and clinicians characteristics.MethodsPerceptions of the ethical climate among clinicians working in 68 adult ICUs in 12 European countries and the US were measured using a self-assessment questionnaire, together with job characteristics and intent to leave as a sub-analysis of the Dispropricus study. The validated ethical decision-making climate questionnaire included seven factors: not avoiding decision-making at end-of-life (EOL), mutual respect within the interdisciplinary team, open interdisciplinary reflection, ethical awareness, self-reflective physician leadership, active decision-making at end-of-life by physicians, and involvement of nurses in EOL. Hierarchical mixed effect models were used to assess associations between these factors, and the intent to leave in clinicians within ICUs, within the different countries.ResultsOf 3610 nurses and 1137 physicians providing ICU bedside care, 63.1% and 62.9% participated, respectively. Of 2992 participating clinicians, 782 (26.1%) had intent to leave, of which 27% nurses, 24% junior and 22.7% senior physicians. After adjustment for country, ICU and clinicians characteristics, mutual respect OR 0.77 (95% CI 0.66- 0.90), open interdisciplinary reflection (OR 0.73 [95% CI 0.62-0.86]) and not avoiding EOL decisions (OR 0.87 [95% CI 0.77-0.98]) were all associated with a lower intent to leave.ConclusionThis is the first large multicenter study showing an independent association between clinicians' intent to leave and the quality of the ethical climate in the ICU. Interventions to reduce intent to leave may be most effective when they focus on improving mutual respect, interdisciplinary reflection and active decision-making at EOL

The complexity of kidney disease and diagnosing it – cystatin C, selective glomerular hypofiltration syndromes and proteome regulation

Estimation of kidney function is often part of daily clinical practice, mostly done by using the endogenous glomerular filtration rate (GFR)-markers creatinine or cystatin C. A recommendation to use both markers in parallel in 2010 has resulted in new knowledge concerning the pathophysiology of kidney disorders by the identification of a new set of kidney disorders, selective glomerular hypofiltration syndromes. These syndromes, connected to strong increases in mortality and morbidity, are characterized by a selective reduction in the glomerular filtration of 5–30 kDa molecules, such as cystatin C, compared to the filtration of small molecules <1 kDa dominating the glomerular filtrate, for example water, urea and creatinine. At least two types of such disorders, shrunken or elongated pore syndrome, are possible according to the pore model for glomerular filtration. Selective glomerular hypofiltration syndromes are prevalent in investigated populations, and patients with these syndromes often display normal measured GFR or creatinine-based GFR-estimates. The syndromes are characterized by proteomic changes promoting the development of atherosclerosis, indicating antibodies and specific receptor-blocking substances as possible new treatment modalities. Presently, the KDIGO guidelines for diagnosing kidney disorders do not recommend cystatin C as a general marker of kidney function and will therefore not allow the identification of a considerable number of patients with selective glomerular hypofiltration syndromes. Furthermore, as cystatin C is uninfluenced by muscle mass, diet or variations in tubular secretion and cystatin C-based GFR-estimation equations do not require controversial race or sex terms, it is obvious that cystatin C should be a part of future KDIGO guidelines.publishedVersio

Outcome in patients perceived as receiving excessive care across different ethical climates: a prospective study in 68 intensive care units in Europe and the USA

Purpose: Whether the quality of the ethical climate in the intensive care unit (ICU) improves the identification of patients receiving excessive care and affects patient outcomes is unknown. Methods: In this prospective observational study, perceptions of excessive care (PECs) by clinicians working in 68 ICUs in Europe and the USA were collected daily during a 28-day period. The quality of the ethical climate in the ICUs was assessed via a validated questionnaire. We compared the combined endpoint (death, not at home or poor quality of life at 1 year) of patients with PECs and the time from PECs until written treatment-limitation decisions (TLDs) and death across the four climates defined via cluster analysis. Results: Of the 4747 eligible clinicians, 2992 (63%) evaluated the ethical climate in their ICU. Of the 321 and 623 patients not admitted for monitoring only in ICUs with a good (n = 12, 18%) and poor (n = 24, 35%) climate, 36 (11%) and 74 (12%), respectively were identified with PECs by at least two clinicians. Of the 35 and 71 identified patients with an available combined endpoint, 100% (95% CI 90.0–1.00) and 85.9% (75.4–92.0) (P = 0.02) attained that endpoint. The risk of death (HR 1.88, 95% CI 1.20–2.92) or receiving a written TLD (HR 2.32, CI 1.11–4.85) in patients with PECs by at least two clinicians was higher in ICUs with a good climate than in those with a poor one. The differences between ICUs with an average climate, with (n = 12, 18%) or without (n = 20, 29%) nursing involvement at the end of life, and ICUs with a poor climate were less obvious but still in favour of the former. Conclusion: Enhancing the quality of the ethical climate in the ICU may improve both the identification of patients receiving excessive care and the decision-making process at the end of life

Ethical climate and intention to leave among critical care clinicians: an observational study in 68 intensive care units across Europe and the United States

Purpose: Apart from organizational issues, quality of inter-professional collaboration during ethical decision-making may affect the intention to leave one’s job. To determine whether ethical climate is associated with the intention to leave after adjustment for country, ICU and clinicians characteristics. Methods: Perceptions of the ethical climate among clinicians working in 68 adult ICUs in 12 European countries and the US were measured using a self-assessment questionnaire, together with job characteristics and intent to leave as a sub-analysis of the Dispropricus study. The validated ethical decision-making climate questionnaire included seven factors: not avoiding decision-making at end-of-life (EOL), mutual respect within the interdisciplinary team, open interdisciplinary reflection, ethical awareness, self-reflective physician leadership, active decision-making at end-of-life by physicians, and involvement of nurses in EOL. Hierarchical mixed effect models were used to assess associations between these factors, and the intent to leave in clinicians within I