Supraglacial forcing of subglacial drainage in the ablation zone of the Greenland ice sheet

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Autosomal dominant cerebellar ataxia type III: a review of the phenotypic and genotypic characteristics

<p>Abstract</p> <p>Autosomal Dominant Cerebellar Ataxia (ADCA) Type III is a type of spinocerebellar ataxia (SCA) classically characterized by pure cerebellar ataxia and occasionally by non-cerebellar signs such as pyramidal signs, ophthalmoplegia, and tremor. The onset of symptoms typically occurs in adulthood; however, a minority of patients develop clinical features in adolescence. The incidence of ADCA Type III is unknown. ADCA Type III consists of six subtypes, SCA5, SCA6, SCA11, SCA26, SCA30, and SCA31. The subtype SCA6 is the most common. These subtypes are associated with four causative genes and two loci. The severity of symptoms and age of onset can vary between each SCA subtype and even between families with the same subtype. SCA5 and SCA11 are caused by specific gene mutations such as missense, inframe deletions, and frameshift insertions or deletions. SCA6 is caused by trinucleotide CAG repeat expansions encoding large uninterrupted glutamine tracts. SCA31 is caused by repeat expansions that fall outside of the protein-coding region of the disease gene. Currently, there are no specific gene mutations associated with SCA26 or SCA30, though there is a confirmed locus for each subtype. This disease is mainly diagnosed via genetic testing; however, differential diagnoses include pure cerebellar ataxia and non-cerebellar features in addition to ataxia. Although not fatal, ADCA Type III may cause dysphagia and falls, which reduce the quality of life of the patients and may in turn shorten the lifespan. The therapy for ADCA Type III is supportive and includes occupational and speech modalities. There is no cure for ADCA Type III, but a number of recent studies have highlighted novel therapies, which bring hope for future curative treatments.</p

Recent loss of floating ice and the consequent sea level contribution

We combine new and published satellite observations and the results of a coupled ice-ocean model to provide the first estimate of changes in the quantity of ice floating in the global oceans and the consequent sea level contribution. Rapid losses of Arctic sea ice and small Antarctic ice shelves are partially offset by thickening of Antarctic sea ice and large Antarctic ice shelves. Altogether, 746 +/- 127 km(3) yr(-1) of floating ice was lost between 1994 and 2004, a value that exceeds considerably the reduction in grounded ice over the same period. Although the losses are equivalent to a small (49 +/- 8 μm yr(-1)) rise in mean sea level, there may be large regional variations in the degree of ocean freshening and mixing. Ice shelves at the Antarctic Peninsula and in the Amundsen Sea, for example, have lost 481 +/- 38 km(3) yr(-1)

Evolution of drainage system morphology at a land-terminating Greenland outlet glacier

This work was funded by the UK Natural Environment Research Council (through grants to Nienow, Mair, and Wadham, and a studentship to Bartholomew), the Edinburgh University Moss Centenary Scholarship (Cowton and Bartholomew), and a Carnegie Research Grant (Nienow). We thank Ian Willis, Tim Bartholomaus and an anonymous referee for valuable comments which significantly improved the manuscript.Peer reviewedPublisher PD

Copper Resistance in Staphylococcus epidermidis: Role of the Multicopper Oxidase Gene

The ongoing struggle against antibiotic resistance and the lack of new antibiotic discoveries being made is a threat to global health. Alternate forms of antibacterial treatment are an important area of research to increase the treatment efficacy of clinical antimicrobial applications. In this research paper, we examine the model organism Staphylcoccus epidermidis, one of the leading causes of nosocomial infection. S. epidermidis normally resides on skin and mucus, however, can become an opportunistic pathogen if it invades the body, entering the bloodstream via the insertion of medical and prosthetic devices. Copper was a traditional therapy in ancient Egypt used for its antimicrobial properties to treat a variety of medical conditions. Despite copper being an effective antibacterial agent, S. epidermidis has been shown to develop resistance against it. To understand which genes likely play a role in copper resistance, we look at previously observed S. epidermidis genes that are upregulated in the presence of copper. From this, the importance of the multicopper oxidase domain-containing protein (EQW00_RS00705) to copper resistance was examined, through clean deletion. Multicopper oxidases (MCOs) are enzymes involved in a variety of processes including metal homeostasis and metal resistance. They have been found to use Cu ions as cofactors to oxidize Cu+ into the less toxic Cu2+ in E. coli. As MCOs are generally conserved, this demonstrates a possible mechanism for copper resistance in S. epidermidis. We expect to find decreased resistance of S. epidermidis EQW00_RS00705 mutant compared to S. epidermidis WT. This would indicate that EQW00_RS00705 significantly contributes to S. epidermidis copper resistance, adding to the knowledge used to develop novel antibiotic treatments against S. epidermidis infection

Children's co-determination during challenging procedures : nurses and parents experiences of caring under short-term hospital stays in Norway

Background: Medical and clinical procedures can cause varying levels of discomfort to children. Purpose: This study is to deepen the understanding of the lived experiences of parents and nurses related to challenging medical and clinical procedures performed on children during short-term hospital stays. Design and Methods: This qualitative study, which comprises part of a larger study, adopted a hermeneutic phenomenological approach. The data were obtained through a combination of in-depth interviews and observations of twelve parents of eleven children and seventeen nurses. A narrative re-analysis was conducted of four challenging medical and clinical procedures. Four stories were written and subsequently analyzed as one narrative that represents the findings. Results: The form of nurses' and parents' care for the children ranged from encouraging the children's consent and receptiveness to the procedures, to coercion. The analysis indicates that promoting the children's co-determination and participation in the procedures encouraged their consent and receptiveness and facilitated a successful outcome. In contrast, an absence of efforts to involve the children in the procedures contributed to the need for coercion to be employed by parents and nurses. Moreover, parental influence and the responsibilities of nurses had an impact on children's co-determination and participation. Conclusions: Preparing parents and children before and during a procedure was important to minimize the degree of coercion of the children. Practice implications: The findings of this study are relevant to clinical practice because they suggest preparing parents and children before and during a procedure situation. Keywords: children in hospital, nurse, parents, lived experience, narrative, procedure situations, coercing, consentpublishedVersio

Analysis of relay protection for generators in offshore facilities

This thesis study how to configure protective relays for protection of generators in offshore oil and gas facilities. On the Norwegian continental shelf, most platforms have isolated power systems with local power generation by a few synchronous generators. Normally, these generators have very similar ratings, also from facility to facility. Due to the natural inherent safety hazards of operating an electrical system in offshore oil and gas facilities, special standards regulate the practice. This applies especially to relay protection of generators because of its essential role for the facility operation combined with its wide range of failure mechanisms. In addition, the electrical system design is also very similar between facilities. All this, makes it possible to find a standard setup for protective relays that are used in such facilities. The thesis identify present standards and regulations that applies to generator protection in these facilities. The underlying reasons for these are also explained. Based on this, the thesis propose functions in the ABB REG670 relay that can be used as a standard solution for all generators in such facilities, to achieve optimal generator protection and full compliance with existing requirements. Relay setting tables for generators in five different facilities is studied to identify how relay protection for generators in these facilities is performed today. Based on this work, the thesis guide how to configure the proposed relay functions. In addition, function parameters that can be set equal for all generators are identified. A study of short-circuits in the power system external to the generator zone is performed. This identifies current contributions from a single generator for different fault types and system configurations. The study showed that a generator relay is not able to detect short circuits on other buses than where it is connected. On this bus, the current contribution from a single generator is unaffected by other equipment connected to the bus. This prove that it is not necessary to perform such a study when upgrading the generator relay

Analysis of the Norwegian-Swedish Market for Green Certificates Using the EMPS Model

Over the last few years it has been important for the European countries to support green energy as a countermeasure against climate changes. Norway and Sweden have chosen to implement a common green certificate market, which is a support scheme for renewable energy technology. The scheme will be a crucial contribution for Norway to abide by EUs' Renewables Directive. So far the market is doing really well and is on track to complete the goal of 26,4 TWh new electricity production from renewables before the end of 2020. The joint certificate market is very closely connected to the power market. Therefore, the EMPS model, which is a good model of the Nordic power market, was chosen as the model to use for testing and forecasting in this thesis. The main objective has been to analyze the Norwegian-Swedish certificate market in the EMPS model with particular focus on factors that affect the green certificate price levels and price fluctuations. This has been done by adjusting and updating a realistic dataset for the Nordic power market. The historic values from the real certificate market were used as inputs and as a basis for the simulations. 10 different cases have been presented and simulated, where the main differences between them were the expansion rate of new production and the expansion of different energy sources. The results obtained from the simulations corresponded to theoretical findings about the green certificate market. Currently the certificate storage holds 13 million certificates, but it appears like it might increase towards a value of 15 million during 2015, before it will start to decrease considerably from 2016. In order to achieve different price scenarios in the simulations, the initial certificate storage needed to be lowered a great deal from the real value, so that the EMPS model could see a possibility of deficit in the future. The most ideal cases with the most even price levels were achieved when the amount of production and consumption of green certificates were as close together as possible. It was demonstrated by the simulations that the expansion rate of new production greatly influences the certificate prices. If the expansion rate is fast, a smaller probability of deficit exists, and as a result the certificate prices will be lower. The opposite is true for a slow expansion rate. The different types of production sources (hydropower, wind power and biofuels) also affected the certificate price levels in different ways, even though the storage developments were the same. When there was more hydropower expansion the average price was the lowest, but the price curve was the most extreme. Expansion in wind power lead to a higher average price, while expansion in biofuels had the most even price curve. A reason for these different price scenarios could be that both hydropower and biofuels can be adjusted in response to power prices. However, different calibrations for the EMPS model had to be performed for the different cases. It is therefore likely that this also influenced the price levels for the different types of production. All things considered, it looks as if 2015 is going to be a very important year regarding the future of the common certificate market. A lot of decisions needs to be made regarding both changes in regulation and potential new investments, which will affect whether the common goal will be met or not. The future is uncertain, but with more work and testing the EMPS model could hopefully predict some of it

Energy flow analysis of a smart thermal grid at Leangen

På Leangen i Trondheim skal det bli bygget et nytt boligområde. Hensikten med denne masteroppgaven er å evaluere hvordan et lokalt lav-temperatur varmenett kan forsyne boligområdet med energi til romoppvarming, produksjon av tappevann og romkjøling. Spillvarme fra en skøytebane i nærheten, samt spillvarme fra gråvann er implementert som en energikilde til lav-temperatur varmenettet. To modeller er utviklet for å undersøke hvilke arbeidsmedium som er best egnet til varmepumpen som skal produsere tappevann. Modell 1 er et system som tar i bruk ammoniakk eller propan som arbeidsmedium og forvarming av tappevann er introdusert. Modell 2 bruker CO2, og tappevannet blir ikke forvarmet. Trondheim Kommune har gitt data fra to energimålere på skøytebanen, og informasjonen er videre brukt til å evaluere hvor mye av energibehovet til boligblokkene spillvarmen kan dekke. Boligblokkene er laget og simulert i Simien som lavenergi-bygg. Spesifikt energibehov for romoppvarming, tappevann og romkjøling er 28,1kWh/m2, 29,8kWh/m2 og 10,6kWh/m2. Resultatene viser at det årlige energibehovet for romoppvarming og tappevannsbehov til én boligblokk kan dekkes av spillvarme fra skøytebanen med 47,5%, mens gråvann kan dekke 33,0%. Det må tilføres energi til varmepumpene i form av elektrisitet, og denne mengden energi utgjør 12,9%. Da har vi resterende 6,6% av energibehovet som må dekkes på andre måter som for eksempel kan være tilførsel av energi fra høy-temperatur fjernvarmenettet. I fremtiden kan det muligens finnes andre spillvarmekilder som kan implementeres og derav dekke hele behovet. Modell 2 som bruker CO2 som arbeidsmedium i varmepumpen ble valgt for videre vurdering. CO2 er det mediumet som oppnår høyest COP ved tappevannsproduksjon hvor høyt temperaturløft er nødvendig. Det var ønskelig å lage et enkelt og funksjonelt system, og modell 2 innebærer færre koblinger da det ikke innebærer forvarming av tappevann. Varmepumpen ble undersøkt når den var forbundet til varmekretsen og kjølekretsen. Ved rundt 10K overopphetning med intern varmeveksler er det mulig å oppnå en COP på 4,5 for CO2-varmepumpen forbundet med varmekretsen og en COP på 4,3 forbundet med kjølekretsen med temperaturene gitt i vårt system. Det er blitt implementert vanntanker for lagring av varmt tappevann for å redusere effekttopper i fjernvarmenettet ved å ha en kontinuerlig vannproduksjon. Høye temperaturer i en lagringstank tilsier mindre volum noe som kan være en fordel i tette boligstrøk samtidig som legionella bakterien ikke klarer å leve i temperaturer over 65 grader celsius. Det er derfor blitt valgt å implementere en lagringstanks forbundet til en bygning som inneholder vann på 75 grader celsius som lagres i en tank på størrelse mellom 1460-2098L. Systemløsningen er basert på en rekke antakelser, og det er derfor viktig å være kritisk til resultatene. Resultatene vil kunne gi et bilde på hvordan ekstern og intern spillvarme kan dekke energibehovet til et stort boligområde og hvordan et lav-temperatur energinett med smarte løsnigner kan senke energibruket i vårt samfunn.At Leangen in Trondheim a new residential area will be built. The purpose with this master thesis is to evaluate how a local low-temperature thermal grid can supply the area considering space heating, domestic hot water production and space cooling. Waste heat from a nearby ice skating rink and waste heat from greywater will be implemented as an energy source for the low-temperature thermal grid. Two models for the energy distribution system have been developed to investigate which working fluid is best suited to produce domestic hot water. Model 1 is a system which uses ammonia or propane as well as preheating of tap water. Model 2 uses CO2 and there is no preheating of water. The municipality of Trondheim have given data from two energy meters at the ice skating rink, and this information is being used further to evaluate the amount of energy demand for the area which can be covered by waste heat. The buildings is simulated in Simien as low-energy consumption buildings. The specific energy demand for space heating and cooling is 28,1kWh/m2 and 10,6kWh/m2, while the demand for hot tap water is 29,8kWh/m2. The results show that the annual energy demand for space heating and production of domestic hot water for one building can be covered by waste heat from the skate rink by 47,5%, while greywater can cover 33,0%. Energy must be supplied to the heat pumps in the form of electricity, and this amount of energy constitutes 12,9%. It remains 6,6% of the energy demand which must be covered in other ways. Heat supply from the high-temperature district heating network could be one solution. In the future, there may exist other waste heat sources that can be implemented and hence cover the entire energy demand. Model 2 using CO2 heat pump was selected for further evaluation due to CO2 being the medium that achieves the highest COP when producing domestic hot water with a high temperature lift. It was desirable to create a simple and functional system, and model 2 involves fewer connections as it does not involve preheating of tap water. The heat pump including internal heat exchanger and system overheating of about 10K achieves a COP of 4,5 for the CO2 heat pump connected to the space heating circuit and a COP of 4,3 connected to the space cooling circuit with the temperatures given in our system. Water tanks have been implemented for thermal storage of hot tap water to reduce the power peaks of the district heating network by having a continuous water production. High temperatures in a storage tank indicate lower volumes which can be an advantage in dense residential areas. In addition, the legionella bacteria can not live in water temperatures over 65 degree celsius. Therefore it has been decided to make storage tanks connected to each building with a temperature level of 75 degree celsius stored in a size of between 1460-2098L. The system solution is based on a number of assumptions, and it is important to be critical of the results. The results will however give a picture of how external and internal waste heat can cover the energy demand of a large residential area and how a low-temperature thermal grid with smart solutions can lower the energy consumption in our society