973 resultados para Sven-Ingar Andersson


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The physiological activator of protein kinase C (PKC), diacylglycerol, is formed by hydrolysis of phosphoinositides (PI) by phospholipase C (PLC) or phosphatidylcholine by phospholipase D (PLD). We have measured activation of these phospholipases by endothelin-1 (ET-1), bradykinin (BK), or phenylephrine (PE) in ventricular myocytes cultured from neonatal rat. The stimulation of PI hydrolysis after 10 min by 0.1 microM ET-1 (about 12-fold) was much greater than for BK or PE (each about four-fold), and did not correlate with translocation of nPKC delta or nPKC epsilon (Clerk A. Bogoyevitch MA. Andersson MB. Sugden PH, 1994. J Biol Chem 269: 32848-32857: Clerk A, Gillespie-Brown J, Fuller SJ, Sugden PH, 1996. Biochem J 317: 109-118). However, ET-1 and BK stimulated a similar rapid increase in [3H]InsP, formation (< 30 s), which was much greater than that seen with PE. This early phase correlated with PKC translocation. Acute or chronic exposure to 12-O-tetradecanoylphorbol-13-acetate (TPA) or treatment with Ro-31-8220 showed that the stimulation of PI hydrolysis by PE, but not ET-1 or BK, was inhibited by activation of PKC. Furthermore, ET-1 and BK heterologously desensitized the stimulation of PI hydrolysis by PE, ET-1 or BK homologously uncoupled their own receptors from [3H]InsP3 formation, but there was no evidence of heterologous desensitization with these two agonists. Anomalously, chronic exposure to TPA increased the stimulation of PI hydrolysis by BK, but this probably resulted from an increase in BK receptor density. PLD was also rapidly activated by TPA. ET-1, BK or PE. Experiments with Ro-31-8220 showed that the stimulation of PLD by ET-1 and BK was mediated through activation of PKC. We discuss the characteristics of the activation of PI hydrolysis and PLD by ET-1, BK, and PE with respect to the translocation of PKC.

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Wild and managed bees are well documented as effective pollinators of global crops of economic importance. However, the contributions by pollinators other than bees have been little explored despite their potential to contribute to crop production and stability in the face of environmental change. Non-bee pollinators include flies, beetles, moths, butterflies, wasps, ants, birds, and bats, among others. Here we focus on non-bee insects and synthesize 39 field studies from five continents that directly measured the crop pollination services provided by non-bees, honey bees, and other bees to compare the relative contributions of these taxa. Non-bees performed 25–50% of the total number of flower visits. Although non-bees were less effective pollinators than bees per flower visit, they made more visits; thus these two factors compensated for each other, resulting in pollination services rendered by non-bees that were similar to those provided by bees. In the subset of studies that measured fruit set, fruit set increased with non-bee insect visits independently of bee visitation rates, indicating that non-bee insects provide a unique benefit that is not provided by bees. We also show that non-bee insects are not as reliant as bees on the presence of remnant natural or seminatural habitat in the surrounding landscape. These results strongly suggest that non-bee insect pollinators play a significant role in global crop production and respond differently than bees to landscape structure, probably making their crop pollination services more robust to changes in land use. Non-bee insects provide a valuable service and provide potential insurance against bee population declines.

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Many studies have aimed to identify common predictors of successful introductions of alien species, but the search has had limited success, particularly for animals. Past research focused primarily on mean trait values, even though genetic and phenotypic variation has been shown to play a role in establishment success in plants and some animals (mostly invertebrates). Using a global database describing 511 introduction events representing 97 mammalian species, we show that intraspecific variation in morphological traits is associated with establishment success, even when controlling for the positive effect of propagule pressure. In particular, greater establishment success is associated with more variation in adult body size but, surprisingly, less variation in neonate body size, potentially reflecting distinct trade-offs and constraints that influence population dynamics differently. We find no mean trait descriptors associated with establishment success, although species occupying wider native distribution ranges (which likely have larger niches) are more successful. Our results emphasize the importance of explicitly considering intraspecific variation to predict establishment success in animal species and generally to understand population dynamics. This understanding might improve management of alien species and increase the success of intentional releases, for example, for biocontrol or reintroductions.

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Heavy precipitation affected Central Europe in May/June 2013, triggering damaging floods both on the Danube and the Elbe rivers. Based on a modelling approach with COSMO-CLM, moisture fluxes, backward trajectories, cyclone tracks and precipitation fields are evaluated for the relevant time period 30 May–2 June 2013. We identify potential moisture sources and quantify their contribution to the flood event focusing on the Danube basin through sensitivity experiments: Control simulations are performed with undisturbed ERA-Interim boundary conditions, while multiple sensitivity experiments are driven with modified evaporation characteristics over selected marine and land areas. Two relevant cyclones are identified both in reanalysis and in our simulations, which moved counter-clockwise in a retrograde path from Southeastern Europe over Eastern Europe towards the northern slopes of the Alps. The control simulations represent the synoptic evolution of the event reasonably well. The evolution of the precipitation event in the control simulations shows some differences in terms of its spatial and temporal characteristics compared to observations. The main precipitation event can be separated into two phases concerning the moisture sources. Our modelling results provide evidence that the two main sources contributing to the event were the continental evapotranspiration (moisture recycling; both phases) and the North Atlantic Ocean (first phase only). The Mediterranean Sea played only a minor role as a moisture source. This study confirms the importance of continental moisture recycling for heavy precipitation events over Central Europe during the summer half year.

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Explosive cyclones are intense extra-tropical low pressure systems featuring large deepening rates. In the Euro-Atlantic sector, they are a major source of life-threatening weather impacts due to their associated strong wind gusts, heavy precipitation and storm surges. The wintertime variability of the North Atlantic cyclonic activity is primarily modulated by the North Atlantic Oscillation (NAO). In this study, we investigate the interannual and multi-decadal variability of explosive North Atlantic cyclones using track density data from two reanalysis datasets (NCEP and ERA-40) and a control simulation of an atmosphere/ocean coupled General Circulation Model (GCM—ECHAM5/MPIOM1). The leading interannual and multi-decadal modes of variability of explosive cyclone track density are characterized by a strengthening/weakening pattern between Newfoundland and Iceland, which is mainly modulated by the NAO at both timescales. However, the NAO control of interannual cyclone variability is not stationary in time and abruptly fluctuates during periods of 20–25 years long both in NCEP and ECHAM5/MPIOM1. These transitions are accompanied by structural changes in the leading mode of explosive cyclone variability, and by decreased/enhanced baroclinicity over the sub-polar/sub-tropical North Atlantic. The influence of the ocean is apparently important for both the occurrence and persistence of such anomalous periods. In the GCM, the Atlantic Meridional Overturning Circulation appears to influence the large-scale baroclinicity and explosive cyclone development over the North Atlantic. These results permit a better understanding of explosive cyclogenesis variability at different climatic timescales and might help to improve predictions of these hazardous events.

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Variations in the spatial configuration of the interstellar magnetic field (ISMF) near the Sun can be constrained by comparing the ISMF direction at the heliosphere found from the Interstellar Boundary Explorer (IBEX) spacecraft observations of a ""Ribbon"" of energetic neutral atoms (ENAs), with the ISMF direction derived from optical polarization data for stars within similar to 40 pc. Using interstellar polarization observations toward similar to 30 nearby stars within similar to 90 degrees of the heliosphere nose, we find that the best fits to the polarization position angles are obtained for a magnetic pole directed toward ecliptic coordinates of lambda, beta similar to 263 degrees, 37 degrees (or galactic coordinates of l, b similar to 38 degrees, 23 degrees), with uncertainties of +/- 35 degrees based on the broad minimum of the best fits and the range of data quality. This magnetic pole is 33 degrees from the magnetic pole that is defined by the center of the arc of the ENA Ribbon. The IBEX ENA ribbon is seen in sight lines that are perpendicular to the ISMF as it drapes over the heliosphere. The similarity of the polarization and Ribbon directions for the local ISMF suggests that the local field is coherent over scale sizes of tens of parsecs. The ISMF vector direction is nearly perpendicular to the flow of local interstellar material (ISM) through the local standard of rest, supporting a possible local ISM origin related to an evolved expanding magnetized shell. The local ISMF direction is found to have a curious geometry with respect to the cosmic microwave background dipole moment.

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Two new lignans, magnovatins A (1) and B (2), along with nine known compounds, were isolated from the leaves of Magnolia ovata. The known compounds were identified as acuminatin (3), licarin A (4), kadsurenin M, 4-O-demethylkadsurenin M, oleiferin A, oleiferin C, spathulenol, parthenolide, and 11,13-dehydrocompressanolide. In addition, compounds I and 2 yielded four new derivatives (1a, 1b, 2a, and 2b). The structures of the new compounds were established on the basis of spectrometric data evaluation. Free-radical scavenging and antimicrobial activities of the major compounds 1, 3, and 4 were investigated.

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The perforated whole-cell configuration of the patch-clamp technique was applied to functionally identified beta-cells in intact mouse pancreatic islets to study the extent of cell coupling between adjacent beta-cells. Using a combination of current- and voltage-clamp recordings, the total gap junctional conductance between beta-cells in an islet was estimated to be 1.22 nS. The analysis of the current waveforms in a voltage-clamped cell ( due to the. ring of an action potential in a neighbouring cell) suggested that the gap junctional conductance between a pair of beta-cells was 0.17 nS. Subthreshold voltage-clamp depolarization (to -55 mV) gave rise to a slow capacitive current indicative of coupling between beta-cells, but not in non-beta-cells, with a time constant of 13.5 ms and a total charge movement of 0.2 pC. Our data suggest that a superficial beta-cell in an islet is in electrical contact with six to seven other beta-cells. No evidence for dye coupling was obtained when cells were dialysed with Lucifer yellow even when electrical coupling was apparent. The correction of the measured resting conductance for the contribution of the gap junctional conductance indicated that the whole-cell K(ATP) channel conductance (G(K,ATP)) falls from approximately 2.5 nS in the absence of glucose to 0.1 nS at 15 mM glucose with an estimated IC(50) of approximately 4 mM. Theoretical considerations indicate that the coupling between beta-cells within the islet is sufficient to allow propagation of [Ca(2+)](i) waves to spread with a speed of approximately 80 mu m s(-1), similar to that observed experimentally in confocal [Ca(2+)](i) imaging.

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Complex fac-[RuCl(3)(NO)(P-N)] (1) was synthesized from the reaction of [RuCl(3)(H(2)O)(2)(NO)] and the P-N ligand, o-[(N,N-dimethylamino)phenyl]diphenylphosphine) in refluxing methanol solution, while complex mer,trans-[RuCl(3)(NO)(P-N)] (2) was obtained by photochemical isomerization of (1) in dichloromethane solution. The third possible isomer mer, cis-[RuCl(3)(NO)(P-N)] (3) was never observed in direct synthesis as well as in photo-or thermal-isomerization reactions. When refluxing a methanol solution of complex (2) a thermally induced isomerization occurs and complex (1) is regenerated. The complexes were characterized by NMR ((31)P{(1)H}, (15)N{1H} and 1H), cyclic voltammetry, FTIR, UV-Vis, elemental analysis and X-ray diffraction structure determination. The (31)P{(1)H} NMR revealed the presence of singlet at 35.6 for (1) and 28.3 ppm for (2). The (1)H NMR spectrum for (1) presented two singlets for the methyl hydrogens at 3.81 and 3.13 ppm, while for (2) was observed only one singlet at 3.29 ppm. FTIR Ru-NO stretching in KBr pellets or CH(2)Cl(2) solution presented 1866 and 1872 cm(-1) for (1) and 1841 and 1860 cm(-1) for (2). Electrochemical analysis revealed a irreversible reduction attributed to Ru(II)-NO(+) -> Ru(II)-NO(0) at -0.81 V and -0.62 V, for (1) and (2), respectively; the process Ru(II) -> Ru(III), as expected, is only observed around 2.0 V, for both complexes. Studies were conducted using (15)NO and both complexes were isolated with (15)N-enriched NO. Upon irradiation, the complex fac-[RuCl(3)(NO)(P-N)] (1) does not exchange (14)NO by (15)NO, while complex mer, trans-[RuCl(3)(NO)(P-N)] (2) does. Complex mer, trans-[RuCl(3)((15)NO)(P-N)] (2`) was obtained by direct reaction of mer, trans-[RuCl(3)(NO)(P-N)] (2) with (15)NO and the complex fac-[RuCl(3)((15)NO)(P-N)] (1`) was obtained by thermal-isomerization of mer, trans-[RuCl(3)((15)NO)(P-N)] (2`). DFT calculation on isomer energies, electronic spectra and electronic configuration were done. For complex (1) the HOMO orbital is essentially Ru (46.6%) and Cl (42.5%), for (2) Ru (57.4%) and Cl (39.0%) while LUMO orbital for (1) is based on NO (52.9%) and is less extent on Ru (38.4%), for (2) NO (58.2%) and Ru (31.5%). (C) 2011 Elsevier B. V. All rights reserved.

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Phytochemical investigation of the bark of Guatteria hispida afforded three new alkaloids, 9-methoxy-O-methylmoschatoline (1), 9-methoxyisomoschatoline (2), and isocerasonine (3), along with 10 known alkaloids, 8-oxopseudopalmatine (4), O-methylmoschatoline (5), lysicamine (6), liriodenine (7), 10-methoxyliriodenine (8), nornuciferine (9), anonaine (10), xylopine (11), coreximine (12), and isocoreximine (13). The major compounds, 2, 6, 12, and 13, showed significant antioxidant capacity in the ORAC(FL), assay. Compounds 5, 6, and 7 were active against S. epidermidis and C. dubliniensis, with MIC values in the range 12.5-100 mu g mL(-1).

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Vårt examensarbete i informatik är utfört på ett producerande företag som expanderat och därför sett behov av att förändra sin organisation. Ägarna upplever att personalplanering och tillverkningsplanering är alltför tidskrävande och de hinner inte med viktiga arbetsuppgifter som marknadsföring och företagsutveckling.Examensarbetet har innefattat teoristudier, en analys av företagets verksamhet samt utformning av förändringsförslag för att förbättra företagets organisation. Våra litteraturstudier har bestått av inläsning av teorier om problem som kan uppstå i expanderande företag samt datainsamling genom intervjuer av företagets ägare och några av de anställda. Detta har legat till grund för den verksamhetsanalys vi genomfört med hjälp av delar ur metoden FA/SIM. Denna analys ligger till grund för de förändringsförslag som har arbetats fram.I analysen har problem som rör följande fyra aktiviteter identifierats. - Arbetsledning - Planering - Tillverkning - VaruleveransDe åtgärdsförslag vi anser viktigast att genomföra för att effektivisera och underlätta arbetssituationen för ägare och anställda är att börja registrera ordrar dagligen och införa rutiner för att registrera produktion och lagerhållning. Ytterligare åtgärder är att anställa kvalificerad personal på kontoret samt utbilda fler i personalen i att köra lackeringen.Vi kan konstatera att företagets övergripande problem till stor del orsakas av att organisationen inte anpassats till företagets expansion. Det är vanligt att insikt om detta kommer först när problemen börjar kännas oöverstigliga.

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Att konstruera ett tidtagningssystem för enduro i skogen leder till flera frågor som måste undersökas och besvaras. Vilken kommunikationsteknik ska användas och vilken systemarkitekturisk lösning passar bäst? Att dra kabel ute i skogen är ett bra sätt att lösa det kommunikationstekniska problemet, lösningen är säker och relativt billig. Visst påverkas priset av distansen mellan olika klienter ute i skogen, men alla positiva egenskaper hos tekniken gör denna kostnad värd sitt pris. De geografiska variationer som kan finnas är de som kan spela ut de övriga teknikerna i form av stabilitet. En snabb resultatförmedling kräver ett system som har en väl uppbyggd systemarkitektur. Vid tidtagning kommer data i form av tider skickas från klienterna direkt till huvudservern, ingen mellanlagring sker utan data lagras centralt vilket förespråkas i IRM. Dessutom kommer ingen redundans att accepteras, vilket även det förespråkas av IRM. Det finns även flera andra parametrar som väger för att välja IRM, vilket är det som rekommenderas utifrån den analys som gjorts i denna uppsats.

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Pappersmakulatur uppstår i tryckpressarna, men orsakerna finns i företagets alla funktioner. För ett framgångsrikt förbättringsarbete med att minska makulaturen krävs därför att all personal är engagerad.Examensarbetet utfördes på Bobergs Tryckeri AB i Falun, ett familjeägt företag med 60 anställda, som producerar personifierad direktreklam och blanketter. Syftet var att undersöka hur pappersmakulaturen kan minska och målet var att hitta orsaker samt ge förslag på åtgärder för att minska den.Genom intervjuer med personalen kartlades produktionssprocessen och utifrån det utarbetades förbättringsförslag. Exempel på förbättringsförslag är att kontinuerligt mäta och rapportera makulaturen, förbättra kommunikationen mellan avdelningarna och utveckla färgstyrningen. Litteraturstudier och kontakter med nyckelpersoner inom branschorganisationer och andra liknande företag, var till stor hjälp i arbetet. Fördjupningsdelen i projektet har sin grund i boken The Printer’s Guide to Waste Reduction av Tim Dalton.

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Intresset för medarbetarsamtal har vuxit under det senaste decenniet, men medarbetar-samtal har beforskats i lite utsträckning. En hypotes som vi har utgått från är att medarbetarsamtalet många gånger inte ges det utrymme som det borde för att gynna organisationen och individen. Studien syfte har varit att skapa kunskap kring vad ett medarbetarsamtal är i offentlig sektor. Det är en kvalitativ undersökning omfattande såväl en litteraturstudie, som en intervjuundersökning med enhetschefer och medarbetare för att få fram medarbetarsamtalets betydelse i den offentliga sektorn. Studien har visat att medarbetarsamtal idealt handlar om individen och organisationens utveckling och ska genomföras en gång per år. I praktiken har vi sett att det mer kommit att handla om att förbättra relationen mellan parterna och att vikten av att bli bekräftad av sin chef som medarbetare är stor. Hur medarbetarsamtalet var utformat varierade bland de enheter som ingick i studien men alla enheterna genomförde medarbetarsamtal en gång per år. Medarbetarsamtalet kan fungera som ett ledningsinstrument och även för att ta reda på behovet av förändring och utveckling inom organisationen. Studien har visat att medarbetarsamtal har relevans för det arbete som utförs på enheten. Dokumentation och uppföljning som görs under medarbetarsamtalet står till största del ledningen för. Litteraturstudien har visat att det saknas forskningsstudier kring området medarbetarsamtal.

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Detta examensarbete beskriver i detalj hur ICC-profiler fo¨r utskriftsmedier, i detta fall fo¨r storformatskrivare, skapas. Examensarbetet omfattade framtagande av ICC-profiler fo¨r substrat till storformatskrivaren Mutoh Toucan PJ-1614NXE (Mutoh Toucan) hos BEMI REKLAM AB (BEMI), Borla¨nge. Fo¨retaget har tidigare anva¨nt en standardlinja¨risering till samtliga substrat fo¨r storformatskrivaren, dock utan att applicera na°gon ICC-profil fo¨r utenheter. Samtliga substrat till Mutoh Toucan a¨r avsedda fo¨r utomhusbruk.