20 research outputs found

    Cochlear implantation : experimental and clinical studies

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    Cochlear implantation makes hearing restoration possible in patients with severe to profound hearing loss. However, patients with residual hearing, where a cochlear implant may be combined with acoustic stimulation, and children with malformed cochleae, where the surgery itself as well as language training may be a challenge, are two important groups of patients that require special procedures. These patient groups are the subject of this thesis. The first study (paper I) examined the effects of cochlear implantation on residual hearing and postoperative histology in a guinea pig model. After mild to moderate levels of surgical trauma, effectuated as a cochleostomy alone or in combination with limited electrode array insertion, hearing recovered after a two-week period of loss (a temporary threshold shift). The intracochlear structures remained unchanged. A second study (paper II) was performed to test the hypothesis that cochlear implantation may induce endolymphatic hydrops, which could lead to hearing loss. The results indicate that hydrops is present during the first week after cochlear implantation. These experimental studies conclude that the guinea pig cochlea shows high resilience to cochlear implantation and that mechanical damage incurred during surgery does not explain the loss of residual hearing often seen in patients. Secondary mechanisms, such as hydrops, are likely to be involved in the early postoperative period. This information is important as patients with useful residual hearing increasingly receive cochlear implants. Two clinical studies examined the effects of cochlear implant surgery on children with x-linked inner ear malformation. The first of these (paper III) describes surgical techniques necessary for safe cochlear implantation, and further shows that implantation permits hearing restoration and the development of spoken language in these children. Further analysis of hearing and language outcomes, cognition and mental health (paper IV) revealed poorer outcome in hearing, language and mental health and lower executive functional level, as compared to a control group. Genetic analysis confirmed mutations in the POU3F4 gene on the X-chromosome. X-linked malformation deafness is usually considered non-syndromic. However, paper IV shows that these children exhibit signs of neuro-developmental problems consistent with attention deficit and hyperactivity, which is likely related to the POU3F4 mutation. Hence, x-linked cochlear malformation should be re-classified as a syndromic form of hearing loss

    The role of extracellular vesicle fusion with target cells in triggering systemic inflammation

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    Extracellular vesicles (EVs) play a crucial role in intercellular communication by transferring bioactive molecules from donor to recipient cells. As a result, EV fusion leads to the modulation of cellular functions and has an impact on both physiological and pathological processes in the recipient cell. This study explores the impact of EV fusion on cellular responses to inflammatory signaling. Our findings reveal that fusion renders non-responsive cells susceptible to inflammatory signaling, as evidenced by increased NF-ÎșB activation and the release of inflammatory mediators. Syntaxin-binding protein 1 is essential for the merge and activation of intracellular signaling. Subsequent analysis show that EVs transfer their functionally active receptors to target cells, making them prone to an otherwise unresponsive state. EVs in complex with their agonist, require no further stimulation of the target cells to trigger mobilization of NF-ÎșB. While receptor antagonists were unable to inhibit NF-ÎșB activation, blocking of the fusion between EVs and their target cells with heparin mitigated inflammation in mice challenged with EVs.</p

    The role of extracellular vesicle fusion with target cells in triggering systemic inflammation

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    Extracellular vesicles (EVs) play a crucial role in intercellular communication by transferring bioactive molecules from donor to recipient cells. As a result, EV fusion leads to the modulation of cellular functions and has an impact on both physiological and pathological processes in the recipient cell. This study explores the impact of EV fusion on cellular responses to inflammatory signaling. Our findings reveal that fusion renders non-responsive cells susceptible to inflammatory signaling, as evidenced by increased NF-ÎșB activation and the release of inflammatory mediators. Syntaxin-binding protein 1 is essential for the merge and activation of intracellular signaling. Subsequent analysis show that EVs transfer their functionally active receptors to target cells, making them prone to an otherwise unresponsive state. EVs in complex with their agonist, require no further stimulation of the target cells to trigger mobilization of NF-ÎșB. While receptor antagonists were unable to inhibit NF-ÎșB activation, blocking of the fusion between EVs and their target cells with heparin mitigated inflammation in mice challenged with EVs.</p

    Implementation of fourth generation district heating in Swedish district heating networks : A case study on BorlÀnge's district heating network

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    För att möta problem med ökande klimatförĂ€ndringar kan fjĂ€rrvĂ€rmen ha en betydande roll ur bĂ„de en svensk och en internationell kontext. Samtidigt stĂ„r svenska fjĂ€rrvĂ€rmebolag inför betydande utmaningar dĂ„ vĂ€rmepumpar blir ett allt vanligare val för att möta uppvĂ€rmnings- och tappvarmvattenbehovet, tillgĂ„ngen till avfall och biomassa som brĂ€nsle förutspĂ„s bli mer begrĂ€nsad och byggnaders uppvĂ€rmningsbehov blir allt lĂ€gre. För att fjĂ€rrvĂ€rme ska fortsĂ€tta vara ett konkurrenskraftigt och hĂ„llbart alternativ för att möta uppvĂ€rmnings- och tappvarmvattenbehovet har konceptet fjĂ€rde generationens fjĂ€rrvĂ€rme (4GDH) tagits fram. 4GDH karaktĂ€riseras av lĂ€gre nĂ€ttemperaturer, fler förnybara energikĂ€llor för fjĂ€rrvĂ€rmeproduktion samt ökad integrering med andra delar av energisystemet. I detta examensarbete har dels möjligheter med att arbeta mot 4GDH i BorlĂ€nge Energis fjĂ€rrvĂ€rmenĂ€t undersökts och dels har potentialen med att uppnĂ„ ett hĂ„llbart energisystem genom att konvertera existerande svenska fjĂ€rrvĂ€rmenĂ€t till 4GDH undersökts. Examensarbetets fokus har primĂ€rt legat pĂ„ den aspekt av 4GDH som innebĂ€r lĂ€gre nĂ€ttemperaturer.  BerĂ€kningar pĂ„ BorlĂ€nges fjĂ€rrvĂ€rmenĂ€t visar att det finns fördelar med att sĂ€nka nĂ€ttemperaturen i form av (1) ökad elproduktion i kraftvĂ€rmeverk (KVV), (2) effektivare rökgaskondensering samt (3) mindre vĂ€rmeförluster. Störst kostnadsbesparingar och undvikta CO2-utslĂ€pp erhĂ„lls genom effektivare rökgaskondensering följt av minskade vĂ€rmeförluster. Den ökade elproduktionen i KVV medförde smĂ„ kostnadsbesparingar och undvikta CO2-utslĂ€pp i förhĂ„llande till tidigare nĂ€mnda faktorer. Simulering av BorlĂ€nges fjĂ€rrvĂ€rmenĂ€t i dagslĂ€get och med 4GDH visade pĂ„ att 4GDH skulle kunna leda till att en stor mĂ€ngd drifttimmar undviks i BorlĂ€nge Energis avfallseldade hetvattenpanna samtidigt som fjĂ€rrvĂ€rmesystemet blir oberoende av fossila brĂ€nslen. Detta innebĂ€r stora undvikta CO2-utslĂ€pp men grundat i att avfallsförbrĂ€nning Ă€r en tjĂ€nst som fjĂ€rrvĂ€rmebolag fĂ„r betalt för i dagslĂ€get leder det totalt sett till en ökade brĂ€nslekostnader för BorlĂ€nge Energi.   Vid analys av kunder i BorlĂ€nges fjĂ€rrvĂ€rmenĂ€t valdes fem fastigheter ut som till stor del uppfyllde framtagna kriterier för att en fastighet skulle lĂ€mpa sig vĂ€l för 4GDH. Av dessa var tre fastigheter planerade byggnationer och tvĂ„ befintliga fastigheter. Av de presenterade tekniska lösningarna fanns endast tydlig ekonomisk lönsamhet, miljönytta och teknisk möjlighet i ett av fallen, dĂ€r majoriteten av fastighetens fjĂ€rrvĂ€rmebehov kunde tĂ€ckas av returvĂ€rme tack vare lĂ„ga temperaturkrav. I tvĂ„ andra fall kunde ekonomisk lönsamhet och miljönytta konstateras men dessa krĂ€vde investeringar av externa aktörer för att tekniskt möjliggöras. I de övriga tvĂ„ fallen begrĂ€nsades den ekonomiska lönsamheten och tekniska möjligheten av ett begrĂ€nsat flöde i nĂ€rliggande returledningar som föreslogs anvĂ€ndas som framledning för lösningarna.  De lĂ„ngsiktiga fördelarna med 4GDH indikerade att det Ă€r ett angreppssĂ€tt man pĂ„ sikt bör jobba vidare med i BorlĂ€nge eftersom det kan bidra till att uppfylla kommunala miljömĂ„l. Samtidigt visade de studerade kundfallen att det finns tydliga hinder för implementering av 4GDH trots att fastigheter bedöms vĂ€l lĂ€mpade för att nyttja lĂ„gtempererad fjĂ€rrvĂ€rme. SĂ„ledes drogs slutsatsen att 4GDH frĂ€mst bör implementeras i form av större sekundĂ€rnĂ€t vilket krĂ€ver samordning av ett flertal aktörer och lĂ„ngsiktig planering. För att stödja BorlĂ€nge Energis arbete mot 4GDH togs en handlingsplan fram med rekommenderade Ă„tgĂ€rder i dagslĂ€get, pĂ„ fem till tio Ă„rs sikt och pĂ„ lĂ€ngre Ă€n tio Ă„rs sikt.  För att avgöra potentialen med 4GDH i svenska fjĂ€rrvĂ€rmenĂ€t generellt nyttjades resultat frĂ„n berĂ€kningar och simuleringar av BorlĂ€nges fjĂ€rrvĂ€rmenĂ€t för att simulera fyra typiska svenska fjĂ€rrvĂ€rmenĂ€t med olika produktionsmixar. Simuleringarna visade pĂ„ att 4GDH i samtliga fall ledde till kostnadsbesparingar och undvikta CO2-utslĂ€pp samtidigt som tillförseltryggheten ökade. Simuleringarna indikerade pĂ„ att fjĂ€rrvĂ€rmenĂ€t dĂ€r restvĂ€rme eller biomassa Ă€r de primĂ€ra energikĂ€llorna frĂ€mst drar fördel med 4GDH i form av minskade brĂ€nslekostnader medan fjĂ€rrvĂ€rmenĂ€t dĂ€r avfall eller fossila brĂ€nslen Ă€r primĂ€ra energikĂ€llor drar större fördel i form av undvikta CO2-utslĂ€pp.  Resultaten frĂ„n detta examensarbete visade att potentialen för att uppnĂ„ ett hĂ„llbart energisystem genom att konvertera svenska fjĂ€rrvĂ€rmenĂ€t till 4GDH Ă€r god. Beroende pĂ„ vilken typ av svenskt fjĂ€rrvĂ€rmenĂ€t det Ă€r bör policys och styrmedel anpassas för att gynna en utveckling mot 4GDH, extra betydande Ă€r detta i fjĂ€rrvĂ€rmenĂ€t dĂ€r avfallsförbrĂ€nning stĂ„r för en betydande del av fjĂ€rrvĂ€rmetillförsel. Generellt kan arbete mot 4GDH pĂ„börjas pĂ„ ett förhĂ„llandevis likvĂ€rdigt vis i svenska fjĂ€rrvĂ€rmenĂ€t, dĂ€rför presenteras en generell metodik för hur svenska fjĂ€rrvĂ€rmebolag kan initiera en omstĂ€llning mot 4GDH.To face the emerging climate crisis, district heating could play an important role both in Sweden and internationally. Meanwhile, Swedish district heating companies are facing major challenges as heat pumps become more common to meet the heating and domestic hot water demand in buildings, the availability of waste and biomass as fuel is predicted to be limited and the heating demand of buildings is reducing. In order for district heating to maintain a competitive and sustainable alternative to meet the heating and domestic hot water demand in buildings, the concept of the fourth generation of district heating (4GDH) has been created. 4GDH is characterized by lower temperatures in the district heating network, more renewable energy sources used for heat production and increased integration with other parts of the energy system. In this master thesis, the possibilities with working towards 4GDH in BorlĂ€nge Energi’s district heating network has been evaluated. Also, the potential of achieving a sustainable energy system by converting existing Swedish district heating networks to 4GDH has been examined. The focus of the master thesis has primarily been on the aspect of 4GDH considering lower network temperatures.  Calculations show benefits with lower temperatures in BorlĂ€nge Energi’s district heating network such as (1) increasing electricity production in the combined heat and power plant (CHP), (2) more efficient flue gas condensation and (3) decreased heat losses. The largest reductions of costs and CO2 emissions are obtained from more efficient flue gas condensation followed by decreased heat losses. The increased electricity production in the CHP plant resulted in smaller reductions of costs and CO2 emissions compared to the above-mentioned factors. Simulations of a scenario where 4GDH is fully implemented in BorlĂ€nge, shows that 4GDH could lead to a lot of operating hours being avoided in the waste-fuelled hot water boiler and the district heating network being independent of fossil fuels. This means significant reductions of CO2 emissions but due to that waste incineration is a service that district heating companies gets paid for the total costs of fuel are increased.   When analysing customers in BorlĂ€nge Energi’s district heating network, five buildings were selected that largely fulfilled presented criterions for a building to suit well in a 4GDH system. Of these five buildings, three were planned buildings and two were existing. Of the presented technical solutions, there were only economic and environmental benefits with few technical barriers in one case. In this case, the heating and domestic hot water demand could mainly be covered by return heat owing to low temperature requirements. In two other cases, the economic and environmental benefits depended heavily on investments by external actors to be technically feasible. In the remaining two cases, the economic benefits and the technical feasibility was limited due to a limited flow in nearby return pipes which were proposed to be used as supply pipe to the buildings.  The long-term benefits with 4GDH indicated that it is an approach that should be continued with in BorlĂ€nge in the long term as it can contribute to reaching municipal environmental targets. However, the studied customer cases showed significant barriers to implementing 4GDH, although the buildings were assessed to be suited well for using low-tempered district heating. Thus, it was concluded that 4GDH should mainly be implemented by building larger low-tempered secondary networks. This requires coordination of multiple actors and long-term planning. To support BorlĂ€nge Energi’s work towards 4GDH, an action plan was presented with recommended measures today, in five to ten years’ time and in more than ten years’ time.  To generalize the results from BorlĂ€nge on a national level, the results from calculations and simulations of BorlĂ€nge Energi’s district heating network were used to simulate four typical Swedish district heating networks with different production mixes. The simulations showed that 4GDH in all cases led to reductions of costs and CO2 emissions and increased security of supply. The simulations indicated that district heating networks where residual heat or biomass is predominantly used mainly benefits from 4GDH through cost reductions, while district heating networks where waste or fossil fuels are predominantly used mainly benefits from 4GDH through reduced CO2 emissions.  The results of this thesis shows that the potential of achieving sustainable energy systems by converting Swedish district heating networks to 4GDH is high. Depending on the characteristics of the district heating network, policies and instruments should be adjusted to support a development towards 4GDH. This is especially important in district heating networks where waste incineration is a major source of the district heating supply. However, work towards 4GDH could generally be initiated in a relatively similar way in Swedish district heating networks. Therefore, a general method for initiating a transition towards 4GDH was presente

    Implementation of fourth generation district heating in Swedish district heating networks : A case study on BorlÀnge's district heating network

    No full text
    För att möta problem med ökande klimatförĂ€ndringar kan fjĂ€rrvĂ€rmen ha en betydande roll ur bĂ„de en svensk och en internationell kontext. Samtidigt stĂ„r svenska fjĂ€rrvĂ€rmebolag inför betydande utmaningar dĂ„ vĂ€rmepumpar blir ett allt vanligare val för att möta uppvĂ€rmnings- och tappvarmvattenbehovet, tillgĂ„ngen till avfall och biomassa som brĂ€nsle förutspĂ„s bli mer begrĂ€nsad och byggnaders uppvĂ€rmningsbehov blir allt lĂ€gre. För att fjĂ€rrvĂ€rme ska fortsĂ€tta vara ett konkurrenskraftigt och hĂ„llbart alternativ för att möta uppvĂ€rmnings- och tappvarmvattenbehovet har konceptet fjĂ€rde generationens fjĂ€rrvĂ€rme (4GDH) tagits fram. 4GDH karaktĂ€riseras av lĂ€gre nĂ€ttemperaturer, fler förnybara energikĂ€llor för fjĂ€rrvĂ€rmeproduktion samt ökad integrering med andra delar av energisystemet. I detta examensarbete har dels möjligheter med att arbeta mot 4GDH i BorlĂ€nge Energis fjĂ€rrvĂ€rmenĂ€t undersökts och dels har potentialen med att uppnĂ„ ett hĂ„llbart energisystem genom att konvertera existerande svenska fjĂ€rrvĂ€rmenĂ€t till 4GDH undersökts. Examensarbetets fokus har primĂ€rt legat pĂ„ den aspekt av 4GDH som innebĂ€r lĂ€gre nĂ€ttemperaturer.  BerĂ€kningar pĂ„ BorlĂ€nges fjĂ€rrvĂ€rmenĂ€t visar att det finns fördelar med att sĂ€nka nĂ€ttemperaturen i form av (1) ökad elproduktion i kraftvĂ€rmeverk (KVV), (2) effektivare rökgaskondensering samt (3) mindre vĂ€rmeförluster. Störst kostnadsbesparingar och undvikta CO2-utslĂ€pp erhĂ„lls genom effektivare rökgaskondensering följt av minskade vĂ€rmeförluster. Den ökade elproduktionen i KVV medförde smĂ„ kostnadsbesparingar och undvikta CO2-utslĂ€pp i förhĂ„llande till tidigare nĂ€mnda faktorer. Simulering av BorlĂ€nges fjĂ€rrvĂ€rmenĂ€t i dagslĂ€get och med 4GDH visade pĂ„ att 4GDH skulle kunna leda till att en stor mĂ€ngd drifttimmar undviks i BorlĂ€nge Energis avfallseldade hetvattenpanna samtidigt som fjĂ€rrvĂ€rmesystemet blir oberoende av fossila brĂ€nslen. Detta innebĂ€r stora undvikta CO2-utslĂ€pp men grundat i att avfallsförbrĂ€nning Ă€r en tjĂ€nst som fjĂ€rrvĂ€rmebolag fĂ„r betalt för i dagslĂ€get leder det totalt sett till en ökade brĂ€nslekostnader för BorlĂ€nge Energi.   Vid analys av kunder i BorlĂ€nges fjĂ€rrvĂ€rmenĂ€t valdes fem fastigheter ut som till stor del uppfyllde framtagna kriterier för att en fastighet skulle lĂ€mpa sig vĂ€l för 4GDH. Av dessa var tre fastigheter planerade byggnationer och tvĂ„ befintliga fastigheter. Av de presenterade tekniska lösningarna fanns endast tydlig ekonomisk lönsamhet, miljönytta och teknisk möjlighet i ett av fallen, dĂ€r majoriteten av fastighetens fjĂ€rrvĂ€rmebehov kunde tĂ€ckas av returvĂ€rme tack vare lĂ„ga temperaturkrav. I tvĂ„ andra fall kunde ekonomisk lönsamhet och miljönytta konstateras men dessa krĂ€vde investeringar av externa aktörer för att tekniskt möjliggöras. I de övriga tvĂ„ fallen begrĂ€nsades den ekonomiska lönsamheten och tekniska möjligheten av ett begrĂ€nsat flöde i nĂ€rliggande returledningar som föreslogs anvĂ€ndas som framledning för lösningarna.  De lĂ„ngsiktiga fördelarna med 4GDH indikerade att det Ă€r ett angreppssĂ€tt man pĂ„ sikt bör jobba vidare med i BorlĂ€nge eftersom det kan bidra till att uppfylla kommunala miljömĂ„l. Samtidigt visade de studerade kundfallen att det finns tydliga hinder för implementering av 4GDH trots att fastigheter bedöms vĂ€l lĂ€mpade för att nyttja lĂ„gtempererad fjĂ€rrvĂ€rme. SĂ„ledes drogs slutsatsen att 4GDH frĂ€mst bör implementeras i form av större sekundĂ€rnĂ€t vilket krĂ€ver samordning av ett flertal aktörer och lĂ„ngsiktig planering. För att stödja BorlĂ€nge Energis arbete mot 4GDH togs en handlingsplan fram med rekommenderade Ă„tgĂ€rder i dagslĂ€get, pĂ„ fem till tio Ă„rs sikt och pĂ„ lĂ€ngre Ă€n tio Ă„rs sikt.  För att avgöra potentialen med 4GDH i svenska fjĂ€rrvĂ€rmenĂ€t generellt nyttjades resultat frĂ„n berĂ€kningar och simuleringar av BorlĂ€nges fjĂ€rrvĂ€rmenĂ€t för att simulera fyra typiska svenska fjĂ€rrvĂ€rmenĂ€t med olika produktionsmixar. Simuleringarna visade pĂ„ att 4GDH i samtliga fall ledde till kostnadsbesparingar och undvikta CO2-utslĂ€pp samtidigt som tillförseltryggheten ökade. Simuleringarna indikerade pĂ„ att fjĂ€rrvĂ€rmenĂ€t dĂ€r restvĂ€rme eller biomassa Ă€r de primĂ€ra energikĂ€llorna frĂ€mst drar fördel med 4GDH i form av minskade brĂ€nslekostnader medan fjĂ€rrvĂ€rmenĂ€t dĂ€r avfall eller fossila brĂ€nslen Ă€r primĂ€ra energikĂ€llor drar större fördel i form av undvikta CO2-utslĂ€pp.  Resultaten frĂ„n detta examensarbete visade att potentialen för att uppnĂ„ ett hĂ„llbart energisystem genom att konvertera svenska fjĂ€rrvĂ€rmenĂ€t till 4GDH Ă€r god. Beroende pĂ„ vilken typ av svenskt fjĂ€rrvĂ€rmenĂ€t det Ă€r bör policys och styrmedel anpassas för att gynna en utveckling mot 4GDH, extra betydande Ă€r detta i fjĂ€rrvĂ€rmenĂ€t dĂ€r avfallsförbrĂ€nning stĂ„r för en betydande del av fjĂ€rrvĂ€rmetillförsel. Generellt kan arbete mot 4GDH pĂ„börjas pĂ„ ett förhĂ„llandevis likvĂ€rdigt vis i svenska fjĂ€rrvĂ€rmenĂ€t, dĂ€rför presenteras en generell metodik för hur svenska fjĂ€rrvĂ€rmebolag kan initiera en omstĂ€llning mot 4GDH.To face the emerging climate crisis, district heating could play an important role both in Sweden and internationally. Meanwhile, Swedish district heating companies are facing major challenges as heat pumps become more common to meet the heating and domestic hot water demand in buildings, the availability of waste and biomass as fuel is predicted to be limited and the heating demand of buildings is reducing. In order for district heating to maintain a competitive and sustainable alternative to meet the heating and domestic hot water demand in buildings, the concept of the fourth generation of district heating (4GDH) has been created. 4GDH is characterized by lower temperatures in the district heating network, more renewable energy sources used for heat production and increased integration with other parts of the energy system. In this master thesis, the possibilities with working towards 4GDH in BorlĂ€nge Energi’s district heating network has been evaluated. Also, the potential of achieving a sustainable energy system by converting existing Swedish district heating networks to 4GDH has been examined. The focus of the master thesis has primarily been on the aspect of 4GDH considering lower network temperatures.  Calculations show benefits with lower temperatures in BorlĂ€nge Energi’s district heating network such as (1) increasing electricity production in the combined heat and power plant (CHP), (2) more efficient flue gas condensation and (3) decreased heat losses. The largest reductions of costs and CO2 emissions are obtained from more efficient flue gas condensation followed by decreased heat losses. The increased electricity production in the CHP plant resulted in smaller reductions of costs and CO2 emissions compared to the above-mentioned factors. Simulations of a scenario where 4GDH is fully implemented in BorlĂ€nge, shows that 4GDH could lead to a lot of operating hours being avoided in the waste-fuelled hot water boiler and the district heating network being independent of fossil fuels. This means significant reductions of CO2 emissions but due to that waste incineration is a service that district heating companies gets paid for the total costs of fuel are increased.   When analysing customers in BorlĂ€nge Energi’s district heating network, five buildings were selected that largely fulfilled presented criterions for a building to suit well in a 4GDH system. Of these five buildings, three were planned buildings and two were existing. Of the presented technical solutions, there were only economic and environmental benefits with few technical barriers in one case. In this case, the heating and domestic hot water demand could mainly be covered by return heat owing to low temperature requirements. In two other cases, the economic and environmental benefits depended heavily on investments by external actors to be technically feasible. In the remaining two cases, the economic benefits and the technical feasibility was limited due to a limited flow in nearby return pipes which were proposed to be used as supply pipe to the buildings.  The long-term benefits with 4GDH indicated that it is an approach that should be continued with in BorlĂ€nge in the long term as it can contribute to reaching municipal environmental targets. However, the studied customer cases showed significant barriers to implementing 4GDH, although the buildings were assessed to be suited well for using low-tempered district heating. Thus, it was concluded that 4GDH should mainly be implemented by building larger low-tempered secondary networks. This requires coordination of multiple actors and long-term planning. To support BorlĂ€nge Energi’s work towards 4GDH, an action plan was presented with recommended measures today, in five to ten years’ time and in more than ten years’ time.  To generalize the results from BorlĂ€nge on a national level, the results from calculations and simulations of BorlĂ€nge Energi’s district heating network were used to simulate four typical Swedish district heating networks with different production mixes. The simulations showed that 4GDH in all cases led to reductions of costs and CO2 emissions and increased security of supply. The simulations indicated that district heating networks where residual heat or biomass is predominantly used mainly benefits from 4GDH through cost reductions, while district heating networks where waste or fossil fuels are predominantly used mainly benefits from 4GDH through reduced CO2 emissions.  The results of this thesis shows that the potential of achieving sustainable energy systems by converting Swedish district heating networks to 4GDH is high. Depending on the characteristics of the district heating network, policies and instruments should be adjusted to support a development towards 4GDH. This is especially important in district heating networks where waste incineration is a major source of the district heating supply. However, work towards 4GDH could generally be initiated in a relatively similar way in Swedish district heating networks. Therefore, a general method for initiating a transition towards 4GDH was presente

    Hydrodynamic Characteristics of the Baihetan Plunge Pool : The Secondary Dam’s Top Elevation Impact on Flow Patterns

    No full text
    The hydrodynamic characteristics of the Baihetan Plunge pool and the impact of changing the secondarydam’s top elevation was investigated. Quantities such as the velocity distribution, turbulencedissipation rate, water surface profile and the probability of a submerged jump forming in the plungepool was studied.The numerical model showed in general good agreement with data gathered from an experimentalstudy conducted in 2012. The only exception was the maximum pressure in the plunge pool, whichwas 16.91 % higher for the simulation using a top elevation of 604 MASL for the secondary dam. Theuse of a grid convergence index (GCI) showed that the result was closer to being mesh independentin the plunge pool (GCIplunge = 4:5 %), but not in the jet body (GCIjet = 16:9 %).The results indicated that no significant improvement was given for changing the top elevationof the secondary dam to 604 or 606 MASL (original height is 602 MASL) since all cases displayflow pattern indicating that a submerged jump will occur. Moreover most of the turbulence wasconcentrated near the jet for all the cases, indicating that the plunge pool is properly designed forthe purpose it is intended to do, i.e. dissipating the energy of the jets in the plunge pool and notdownstream to the unprotected riverbanks.The main conclusion is that the original design is to prefer since no advantages is given byheightening the secondary dam, and will only increase the cost of construction

    X-linked Malformation Deafness : Neurodevelopmental Symptoms Are Common in Children With IP3 Malformation and Mutation in POU3F4

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    Objective: Incomplete partition type 3 (IP3) malformation deafness is a rare hereditary cause of congenital or rapid progressive hearing loss. The children present with a severe to profound mixed hearing loss and temporal bone imaging show a typical inner ear malformation classified as IP3. Cochlear implantation is one option of hearing restoration in severe cases. Little is known about other specific difficulties these children might exhibit, for instance possible neurodevelopmental symptoms. Material and methods: Ten 2; 0 to 9; 6-year-old children with IP3 malformation deafness (nine boys and one girl) with cochlear implants were evaluated with a retrospective chart review in combination with an additional extensive multidisciplinary assessment day. Hearing, language, cognition, and mental ill-health were compared with a control group of ten 1; 6 to 14; 5-year-old children with cochlear implants (seven boys and three girls) with another genetic cause of deafness, mutations in the GJB2 gene. Results: Mutations in POU3F4 were found in nine of the 10 children with IP3 malformation. Children with IP3 malformation deafness had an atypical outcome with low level of speech recognition (especially in noise), executive functioning deficits, delayed or impaired speech as well as atypical lexical-semantic and pragmatic abilities, and exhibited mental ill-health issues. Parents of children with IP3 malformation were more likely to report that they were worried about their childs psychosocial wellbeing. Controls, however, had more age-typical results in all these domains. Eight of 10 children in the experimental group had high nonverbal cognitive ability despite their broad range of neurodevelopmental symptoms. Conclusions: While cochlear implantation is a feasible alternative for children with IP3 malformation deafness, co-occurring neurodevelopmental anomalies, such as attention deficit hyperactivity or developmental language disorder, and mental ill-health issues require an extensive and consistent multidisciplinary team approach during childhood to support their overall habilitation.Funding Agencies|Horselskadades Riksforbund (National Association of Hearing Impairment); ALF ( Stockholm County Council)Stockholm County Council; ALF (Karolinska Institute); ALF (Karolinska Hospital)</p
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