P-Type ATPase TAT-2 Negatively Regulates Monomethyl Branched-Chain Fatty Acid Mediated Function in Post-Embryonic Growth and Development in C. elegans

Monomethyl branched-chain fatty acids (mmBCFAs) are essential for Caenorhabditis elegans growth and development. To identify factors acting downstream of mmBCFAs for their function in growth regulation, we conducted a genetic screen for suppressors of the L1 arrest that occurs in animals depleted of the 17-carbon mmBCFA C17ISO. Three of the suppressor mutations defined an unexpected player, the P-type ATPase TAT-2, which belongs to the flippase family of proteins that are implicated in mediating phospholipid bilayer asymmetry. We provide evidence that TAT-2, but not other TAT genes, has a specific role in antagonizing the regulatory activity of mmBCFAs in intestinal cells. Interestingly, we found that mutations in tat-2 also suppress the lethality caused by inhibition of the first step in sphingolipid biosynthesis. We further showed that the fatty acid side-chains of glycosylceramides contain 20%–30% mmBCFAs and that this fraction is greatly diminished in the absence of mmBCFA biosynthesis. These results suggest a model in which a C17ISO-containing sphingolipid may mediate the regulatory functions of mmBCFAs and is negatively regulated by TAT-2 in intestinal cells. This work indicates a novel connection between a P-type ATPase and the critical regulatory function of a specific fatty acid

Konstsnö och dess effekter på vegetationen : Skillnader mellan konstsnö och natursnö

Increased temperatures, changed snow conditions, increasing demand for skiing and other winter sports lead to increased demand and production of artificial snow. Besides the positive aspects of artificial snow, it is important to understand potentially negative effects of artificial snow on the environment and vegetation. This study investigated the differences between artificial snow and natural snow in two adjacent ski slopes. This was done by measuring and comparing the snow depth, duration of the snow cover, snow density, and ground vegetation between the slopes. Snow depth and density showed differences between artificial snow and natural snow. The artificial snow cover stayed about 11 days longer than the natural snow. A few variations in the vegetation were also found; earlier flowering and more species and colors in the natural snow slope compared to in the slope using artificial snow. Therefore, it is clear that there is a difference between artificial snow and natural snow, and that this results in effects on the environment, but it is difficult to assess to what extent and how large the negative impact is. For more general conclusions, I think it is important to study the vegetation under artificial snow during a longer period and in several areas

Large-scale logistics system for hydrogen transport

Energiomställningen är avgörande för att begränsa de globala koldioxidutsläppen. Det blir det allt viktigare att hitta sätt att ta tillvara på elöverskott och kunna lagra energi från förnybara energikällor som vind och sol. Vätgas är en energibärare och har stor potential för att ha en nyckelroll i ett hundraprocentigt förnybart energisystem. Syftet med studien var att undersöka förutsättningarna för ett ekonomiskt och tekniskt håll- bart logistiksystem för vätgastransport. Målet var att beräkna överföringskostnader och jämföra olika tekniker för transport av vätgas. Studien inleddes med en djupgående litte- raturstudie och omvärldsanalys. Därefter valdes två olika fall i norra Sverige och utifrån de förutsättningar som fanns på platserna jämfördes transport via pipeline, vägtransport och järnvägstransport. Resultaten för vägtransport via komprimerad form tyder på att det krävs ett stort antal transporter för att leverera den analyserade mängden i de olika fallen vilket resulterar i höga kostnader. Transport via järnväg tyder på relativt hög investeringskostnad och ingen större skillnad mellan fallen. Resultaten tyder på att transport via pipeline har relativt låga överföringskostnader för båda fallen och man kan se en skillnad i investeringskostnad mellan fallen. Överföringskostnader via pipeline tyder på lägre kostnader än att överföra el. Överföringskostnader kan bero på olika faktorer som förutsättningar på platsen, elkostnader, avstånd och volym. Det finns osäkerheter i resultaten för vägtransport och järnväg vilket gör det svårt att dra slutsaster utifrån den data som presenteras. Jämförelsen mellan vätgas och el ska ses som en grov uppskattning på grund av de osäkerheter som finns kopplat till elöverföringen.The energy transition is crucial to limit the global carbon dioxide emissions. Renewable energy sources like wind and solar are intermittent and we need to find ways to use the electricity surplus and store energy. Hydrogen is an energy carrier and has the potential to be a key to achieve a renewable energy system. The aim of the study is to investigate the feasibility for an economic and technical sustainable system for hydrogen distribution. The goal was to calculate transmission cost for different types of hydrogen transport. A profound literature study and external analysis was made in the beginning. Then two cases were selected in the northern part of Sweden. Based on the conditions, transport through pipeline, road transport and transport by rail were choosen. The results for transport by road suggests that very frequent transports are required to deliver the quantity in the cases taken up, which results in high costs. Distribution cost by rail implies high investment costs and there are no significant difference between distribution cost for the cases. Furthermore the results implies that pipeline has low operating costs for both cases and it also implies a difference between investments cost for the cases. The result also indicates that transmission cost by pipelines is cheaper than transmission cost for electricity. Which one is the best option depends on many different factors such as conditions at the location, electricity price, distance and the volume. There are uncertainties in the results for transport by road and by rail, which makes it difficult to conclude based on the current findings. The comparision between hydrogen and electricity should be seen as a rough estimate due to the uncertanties

Konstsnö och dess effekter på vegetationen : Skillnader mellan konstsnö och natursnö

Increased temperatures, changed snow conditions, increasing demand for skiing and other winter sports lead to increased demand and production of artificial snow. Besides the positive aspects of artificial snow, it is important to understand potentially negative effects of artificial snow on the environment and vegetation. This study investigated the differences between artificial snow and natural snow in two adjacent ski slopes. This was done by measuring and comparing the snow depth, duration of the snow cover, snow density, and ground vegetation between the slopes. Snow depth and density showed differences between artificial snow and natural snow. The artificial snow cover stayed about 11 days longer than the natural snow. A few variations in the vegetation were also found; earlier flowering and more species and colors in the natural snow slope compared to in the slope using artificial snow. Therefore, it is clear that there is a difference between artificial snow and natural snow, and that this results in effects on the environment, but it is difficult to assess to what extent and how large the negative impact is. For more general conclusions, I think it is important to study the vegetation under artificial snow during a longer period and in several areas

Recent trends in the use of antidepressant drugs in Australia, 1990-1998

Copyright © 2000 Australasian Medical PublishingObjective: To determine the pattern of use of antidepressant drugs in the Australian community, 1990-1998, and to compare this with those of other developed countries. Design: Retrospective analyses of prescription and sales data, together with information about patient encounters for depression (from an ongoing survey of service provision by general practitioners) and population-based prevalence estimates for affective disorders (from community health surveys). Main outcome measures: National and international consumption of antidepressants, expressed in defined daily doses (DDDs) per 1000 population per day. Changes in both the frequency of general practice patient encounters for depression and population-based prevalence estimates for affective disorders. Results: Dispensing of antidepressant prescriptions through community pharmacies in Australia increased from an estimated 12.4 DDDs/1000 population per day in 1990 (5.1 million prescriptions) to 35.7 DDDs/1000 population/day in 1998 (8.2 million prescriptions). There has been a rapid market uptake of the selective serotonin reuptake inhibitors (SSRIs), accompanied by a decrease of only 25% in the use of tricyclic antidepressants (TCAs). In 1998, the level of antidepressant use in Australia was similar to that of the United States, while the rate of increase in use between 1993 and 1998 was second only to that of Sweden. In Australia, depression has risen from the tenth most common problem managed in general practice in 1990-91 to the fourth in 1998-99, and the number of people reporting depression in the National Health Surveys (1995 v 1989-90) has almost doubled. Of the prescriptions dispensed in 1998 for antidepressant drugs subsidised by the Pharmaceutical Benefits Scheme, 85% were written by general practitioners, and 11.2% by psychiatrists. Conclusions: As in most developed countries, antidepressant use increased between 1990 and 1998. The rapid market uptake of the new antidepressants, particularly SSRIs, is likely to have been driven by increased awareness of depression, together with availability and promotion of new therapies.Peter McManus, Andrea Mant, Philip B Mitchell William S Montgomery, John Marley and Merran E Aulan