984 resultados para Nucleate Pool Boiling
Resumo:
Abstract The epithelial sodium channel (ENaC) is composed of three homologous subunits α, ß, and γ. This channel is involved in the regulation of sodium balance, which influences the periciliary liquid level in the lung, and blood pressure via the kidney. ENaC expressed in Xenopus laevis oocytes is preferentially and rapidly assembled into heteromeric αßγ complexes. Expression of homomeric α or heteromeric αß and αγ complexes lead to channel expression at the cell surface wíth low activities. Recent studies have demonstrated that α and γ (but not ß) ENaC subunits undergo proteolytic cleavage by endogenous proteases (i.e. furin) correlating with increased channel activity. We therefore assayed the full-length subunits and their cleavage products at the cell surface, as well as in the intracellular pool for all homo- and heteromeric combínations (α, ß, γ, ßγ, αß, αγ, ßγ and αßγ) and measured the corresponding channel activities as amiloride-sensitive sodíum transport (INa). We showed that upon assembly, cleavage of the y ENaC subunit ís responsible for increasing INa. We further demonstrated that in disease states such as cystic fibrosis (CF) where there is disequilibrium in the proteaseprotease inhibitor balance, ENaC is over-activated by the serine protease elastase (NE). We demonstrated that elevated NE concentrations can cleave cell surface expressed γ ENaC (but not α, or ß ENaC), suggesting a causal relationship between γ ENaC cleavage and ENaC activation, taking place at the plasma membrane. In addition, we demonstrated that the serine protease inhibitor (serpin) serpinH1, which is co-expressed with ENaC in the distal nephron is capable of inhibiting the channel by preventing cleavage of the γ ENaC subunit. Aldosterone mediated increases in INa aze known to be inhibted by TGFß. TGFß is also known to increase serpinHl expression. The demonstrated inhibition of γ ENaC cleavage and channel activation by serpinH1 may be responsible for the effect of TGFß on aldosterone stimulation in the distal nephron. In summary, we show that cleavage of the γ subunit, but not the α or ß subunit is linked to channel activation in three seperate contexts. Résumé Le canal épithélial à sodium (ENaC) est constitué de trois sous-unités homologues α, ß, and γ. Ce canal est impliqué dans le maintien de la balance sodique qui influence le niveau du liquide périciliaire du poumon et la pression sanguine via le rein. Dans les ovocytes de Xenopus laevis ENaC est préférentiellement et rapidement exprimé en formant un complexe hétéromérique αßγ. En revanche, l'expression homomérique de α ou hétéromérique des complexes αß et αγ conduit à une expression à la surface cellulaire d'un canal ENaC ne possédant qu'une faible activité. Des études récentes ont mis en évidence que les sous-unités α et γ d'ENaC (mais pas ß) sont coupées par des protéases endogènes (les farines) et que ces clivages augmentent l'activité du canal. Nous avons donc analysé, aussi bien à la surface cellulaire que dans le cytoplasme, les produits des clivages de combinaison homo- et hétéromérique des sous-unités d'ENaC (α, ß, γ, ßγ, αß, αγ, ßγ et αßγ). En parallèle, nous avons étudié l'activité correspondante à ces canaux par la mesure du transport de sodium sensible à l'amiloride (INa). Nous avons montré que lors de l'assemblage des sous-unités d'ENaC, le clivage de γ correspond à l'augmentation de INa. Nous avons également mis en évidence que dans une maladie telle que la fibrose cystique (CF) caractérisée par un déséquilibre de la balance protéase-inhibiteur de protéase, ENaC est suractivé par une sérine protéase nommée élastase (NE). L'augmentation de la concentration de NE clive γ ENaC exprimé à la surface cellulaire (mais pas α, ni ß ENaC) suggérant une causalité entre le clivage d'ENaC et son activation à la membrane plasmique. De plus, nous avons démontré que l'inhibiteur de sérine protéase (serpin) serpinH1, qui est co-exprimé avec ENaC dans le néphron distal, inhibe l'activité du canal en empêchant le clivage de la sous-unité γ ENaC. Il est connu que le INa induit par l'aldostérone peut être inhibé par TGFß. Or TGFß augmente l'expression de serpinH1. L'inhibition du clivage de γ ENaC et de l'activation du canal par la serpinH1 que nous avons mis en évidence pourrait ainsi être responsable de l'effet de TGFß sur la stimulation du courant par l'aldostérone dans le néphron distal. En résumé, nous avons montré que le clivage de la sous-unité γ, mais pas des sous-unités α et ß, est lié à l'activation du canal dans trois contextes distincts. Résumé tout public Le corps humain est composé d'environ 10 000 milliards de cellules et d'approximativement 60% d'eau. Les cellules du corps sont les unités fondamentales de la vie et elles sont dépendantes de certains nutriments et molécules. Ces nutriments et molécules sont dissous dans l'eau qui est présente dans et hors des cellules. Le maintien d'une concentration adéquate - de ces nutriments et de ces molécules dans l'eau à l'intérieur et à l'extérieur des cellules est -..essentiel pour leur survie. L'eau hors des cellules est nommée le fluide extracellulaire et peut être subdivisée en fluide interstitiel, qui se trouve autour des cellules, et en plasma, qui est le fluide des vaisseaux sanguins. Les fluides, les nutriments et les molécules sont constamment échangés entre les cellules, le fluide interstitiel, et le plasma. Le plasma circule dans le système circulatoire afin de distribuer les nutriments et molécules dans tout le corps et afin d'enlever les déchets cellulaires. Le rein joue un rôle essentiel dans la régulation du volume et de la concentration du plasma en éliminant sélectivement les nutriments et les molécules via la formation de l'urine. L'être humain possède deux reins, constitués chacun d'environ 1 million de néphrons. Ces derniers sont responsables de réabsorber et de sécréter sélectivement les nutriments et les molécules. Le canal épithélial à sodium (ENaC) est localisé à la surface cellulaire des néphrons et est responsable de la réabsorption du sodium (Na+). Le Na+ est présent dans quasiment toute la nourriture que nous mangeons et représente, en terme de molécule, 50% du sel de cuisine. Si trop de sodium est consommé, ENaC est inactif, si bien que le Na+ n'est pas réabsorbé et quitte le corps par l'urine. Ce mécanisme permet d'éviter que la concentration plasmatique de Na+ ne devienne trop grande, ce qui résulterait en une augmentation de la pression sanguine. Si trop peu de Na+ est consommé, ENaC réabsorbe le Na+ de l'urine primaire ce qui permet de conserver la concentration de Na+ et de prévenir une diminution de la pression sanguine par une perte de Na+. ENaC est aussi présent dans les cellules des poumons qui sont les organes permettant la respiration. La respiration est aussi essentielle pour la survie des cellules. Les poumons ne doivent pas contenir trop de liquide afin de permettre la respiration, mais en même temps ils ne doivent pas non plus être trop secs. En effet, ceci tuerait les cellules et empêcherait aussi la respiration. ENaC permet de maintenir un niveau d'humidité approprié dans les poumons en absorbant du Na+ ce qui entraîne un mouvement osmotique d'eau. L'absorption de sodium par ENaC ~ est augmentée par les protéases (in vitro et ex vivo). Les protéases sont des molécules qui peuvent couper d'autres molécules à des endroits précis. Nous avons démonté que certaines protéases augmentent l'absorption de Na+ en coupant ENaC à des endroits spécifiques. L'inhibition de ces protéases diminue le transport de Na+ et empêche le clivage d'ENaC. Dans certaines maladies telle que la mucoviscidose, des protéases sont suractivées et augmentent l'activité d'ENaC de manière inappropriée conduisant à une trop forte absorption de Na+ et à un déséquilibre de la muqueuse des poumons. Cette étude est donc particulièrement importante dans le cadre de la recherche thérapeutique de ce genre de maladie.
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Clines in life history traits, presumably driven by spatially varying selection, are widespread. Major latitudinal clines have been observed, for example, in Drosophila melanogaster, an ancestrally tropical insect from Africa that has colonized temperate habitats on multiple continents. Yet, how geographic factors other than latitude, such as altitude or longitude, affect life history in this species remains poorly understood. Moreover, most previous work has been performed on derived European, American and Australian populations, but whether life history also varies predictably with geography in the ancestral Afro-tropical range has not been investigated systematically. Here, we have examined life history variation among populations of D. melanogaster from sub-Saharan Africa. Viability and reproductive diapause did not vary with geography, but body size increased with altitude, latitude and longitude. Early fecundity covaried positively with altitude and latitude, whereas lifespan showed the opposite trend. Examination of genetic variance-covariance matrices revealed geographic differentiation also in trade-off structure, and QST -FST analysis showed that life history differentiation among populations is likely shaped by selection. Together, our results suggest that geographic and/or climatic factors drive adaptive phenotypic differentiation among ancestral African populations and confirm the widely held notion that latitude and altitude represent parallel gradients.
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Outcrops of old strata at the shelf edge resulting from erosive gravity-driven flows have been globally described on continental margins. The reexposure of old strata allows for the reintroduction of aged organic carbon (OC), sequestered in marine sediments for thousands of years, into the modern carbon cycle. This pool of reworked material represents an additional source of C-14-depleted organic carbon supplied to the ocean, in parallel with the weathering of fossil organic carbon delivered by rivers from land. To understand the dynamics and implications of this reexposure at the shelf edge, a biogeochemical study was carried out in the Gulf of Lions (Mediterranean Sea) where erosive processes, driven by shelf dense water cascading, are currently shaping the seafloor at the canyon heads. Mooring lines equipped with sediment traps and current meters were deployed during the cascading season in the southwestern canyon heads, whereas sediment cores were collected along the sediment dispersal system from the prodelta regions down to the canyon heads. Evidence from grain-size, X-radiographs and Pb-210 activity indicate the presence in the upper slope of a shelly-coarse surface stratum overlying a consolidated deposit. This erosive discontinuity was interpreted as being a result of dense water cascading that is able to generate sufficient shear stress at the canyon heads to mobilize the coarse surface layer, eroding the basal strata. As a result, a pool of aged organic carbon (Delta C-14 = -944.5 +/- 24.7%; mean age 23,650 +/- 3,321 ybp) outcrops at the modern seafloor and is reexposed to the contemporary carbon cycle. This basal deposit was found to have relatively high terrigenous organic carbon (lignin = 1.48 +/- 0.14 mg/100 mg OC), suggesting that this material was deposited during the last low sea-level stand. A few sediment trap samples showed anomalously depleted radiocarbon concentrations (Delta C-14 = -704.4 +/- 62.5%) relative to inner shelf (Delta C-14 = -293.4 +/- 134.0%), mid-shelf (Delta C-14 = -366.6 +/- 51.1%), and outer shelf (Delta C-14 = -384 +/- 47.8%) surface sediments. Therefore, although the major source of particulate material during the cascading season is resuspended shelf deposits, there is evidence that this aged pool of organic carbon can be eroded and laterally advected downslope.
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Monte Carlo (MC) simulations have been used to study the structure of an intermediate thermal phase of poly(R-octadecyl ç,D-glutamate). This is a comblike poly(ç-peptide) able to adopt a biphasic structure that has been described as a layered arrangement of backbone helical rods immersed in a paraffinic pool of polymethylene side chains. Simulations were performed at two different temperatures (348 and 363 K), both of them above the melting point of the paraffinic phase, using the configurational bias MC algorithm. Results indicate that layers are constituted by a side-by-side packing of 17/5 helices. The organization of the interlayer paraffinic region is described in atomistic terms by examining the torsional angles and the end-to-end distances for the octadecyl side chains. Comparison with previously reported comblike poly(â-peptide)s revealed significant differences in the organization of the alkyl side chains.
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Planarian flatworms are an exception among bilaterians in that they possess a large pool of adult stem cells that enables them to promptly regenerate any part of their body, including the brain. Although known for two centuries for their remarkable regenerative capabilities, planarians have only recently emerged as an attractive model for studying regeneration and stem cell biology. This revival is due in part to the availability of a sequenced genome and the development of new technologies, such as RNA interference and next-generation sequencing, which facilitate studies of planarian regeneration at the molecular level. Here, we highlight why planarians are an exciting tool in the study of regeneration and its underlying stem cell biology in vivo, and discuss the potential promises and current limitations of this model organism for stem cell research and regenerative medicine.
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The aim of the present study was to identify Candida albicans transcription factors (TFs) involved in virulence. Although mice are considered the gold-standard model to study fungal virulence, mini-host infection models have been increasingly used. Here, barcoded TF mutants were first screened in mice by pools of strains and fungal burdens (FBs) quantified in kidneys. Mutants of unannotated genes which generated a kidney FB significantly different from that of wild-type were selected and individually examined in Galleria mellonella. In addition, mutants that could not be detected in mice were also tested in G. mellonella. Only 25% of these mutants displayed matching phenotypes in both hosts, highlighting a significant discrepancy between the two models. To address the basis of this difference (pool or host effects), a set of 19 mutants tested in G. mellonella were also injected individually into mice. Matching FB phenotypes were observed in 50% of the cases, highlighting the bias due to host effects. In contrast, 33.4% concordance was observed between pool and single strain infections in mice, thereby highlighting the bias introduced by the "pool effect." After filtering the results obtained from the two infection models, mutants for MBF1 and ZCF6 were selected. Independent marker-free mutants were subsequently tested in both hosts to validate previous results. The MBF1 mutant showed impaired infection in both models, while the ZCF6 mutant was only significant in mice infections. The two mutants showed no obvious in vitro phenotypes compared with the wild-type, indicating that these genes might be specifically involved in in vivo adapt.
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Yritykset tekevät nykyään yhä enemmän yhteistyötä keskenään eli verkostoituvat. Verkostoitumisella haetaan kykyä vastata nopeasti muuttuvan toimintaympäristön haasteisiin. Tässä diplomityössä tutkitaan testaus- ja laboratoriopalveluiden saatavuuden kehittämistä verkostoitumisen keinoin.Alueellisia testaus- ja laboratoriopalveluiden saatavuutta parannetaan valjastamalla käyttöön yritysten yksityisessä käytössä olevat tuotekehityslaboratoriot ja niiden vapaa kapasiteetti. Verkoston ytimen muodostaa teknologiapalvelu, joka hallitsee tietoa yritysten resursseista ja jakaa tätä tietoa. Työssä kartoitettiin alueella olevista yrityksistä heidän tarpeitaan tuotekehityksen aikaiselle testaukselle, tähän sopivia olemassa olevia laitteita ja tiloja ja yritysten mielipiteitä toiminnan organisoimisesta. Lisäksi tutkittiin tuotekehityksen aikana tarvittavaa direktiivitietouden tarvetta yrityksissä. Yritykset suhtautuivat erittäin myönteisesti yhteistyön tekemiseen testaus- ja laboratoriotoiminnassa. Yrityksistä löytyi erilaisia testauslaitteita ja –tiloja, ja näitä on muidenkin yritysten mahdollista käyttää tietyin ehdoin, kunhan se ei häiritse yrityksen omaa tuotekehitystyötä ja vapaata kapasiteettia löytyy.
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Työn aiheena on siistausmassan saostuksessa käytettävä kiekkosuodatinväliaine ja tarkoituksena selvittää lankamateriaalien ja pinnoitusaineiden vaikutusta väliaineen likaantumisherkkyyteen ja suodatusteknisiin ominaisuuksiin. Siistauslaitosten ongelmana on suodatinväliaineen likaantuminen massassa olevien tahmo- ja painoväripartikkelien johdosta. Tällä hetkellä siistauslaitosten kiekkosuodatinpussien valmistuksessa käytetään pääasiassa polypropeeni- ja polyvinylideenifluoridimonofilamenttilankoja, joiden lianhylkivyys on osoittautunut huonoksi. Uusiksi lankamateriaaleiksi tutkimuksiin valittiin Easy Kleen I, Easy Kleen II, Hyflon, Halar ja Polyesteri. Tulosten perusteella Easy Kleen I ja II monofilamenttilangoista kudotun suodatinkankaan lianhylkivyys on polypropeeni- ja polyvinylideenifluoridimonofilamenttilangoista kudottua kangasta parempi. Suodatusteknisissä ominaisuuksissa ei materiaalien välillä havaittu merkittävää eroa. Easy Kleen monofilamenttilangat näyttävät soveltuvan myös keittokutistumiltaan ja mekaanisilta ominaisuuksiltaan kiekkosuodatinpussien materiaaleiksi. Polypropeeni- ja polyesterimonofilamenettilangoista kudottujen suodatinkankaiden pinnoittamisessa käytettiin hydrofiilisiä ja hydrofobisia pinnoitusaineita. Tulosten perusteella on mahdollista parantaa suodatinkankaan lianhylkivyyttä pinnoittamalla. Pinnoitettu kangas on myös suodatusteknisiltä ominaisuuksiltaan toimiva. Ongelmaksi suodatinkankaiden pinnoittamisessa saattaa kuitenkin muodostua pinnoituslämpötila, jossa kangas kutistuu asennuskelvottomaksi.
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Background: The number of patients who have undergone intravitreal injections has increased enormously in recent years, but a consensus is still lacking on prophylaxis for endophthalmitis. The aim of this prospective, observational study was to evaluate the prophylactic effect of azithromycin eye drops versus ofloxacin eye drops. Methods: The study was conducted in five hospitals in Spain and included all patients under going intravitreal injections of triamcinolone, bevacizumab, ranibizumab, or pegaptanib over one year. Patients received azithromycin 15 mg/g eye drops (twice daily on the day prior to injection and for another 2 days) or ofloxacin 3 mg/g eye drops (every 6 hours on the day prior to injection and for another 7 days). Results: In the azithromycin group, there were 4045 injections in 972 eyes of 701 patients. In the ofloxacin group, there were 4151 injections in 944 eyes of 682 patients. There were two cases of endophthalmitis (0.049%) in the azithromycin group and five (0.12%) in the ofloxacin group. The odds ratio of presenting with endophthalmitis in the ofloxacin group compared with the azithromycin group was 2.37 (95% confidence interval [CI] 1.32-3.72, P ,0.001). There were two cases of noninfectious uveitis after triamcinolone injection in the azithromycin group (0.049%) and two (0.048%) in the ofloxacin group; no significant differences were observed (odds ratio 0.902, 95% CI 0.622-1.407, P= 0.407). Conjunctival hyperemia was observed in 12 cases in the azithromycin group and none in the ofloxacin group. Conclusion: The risk of endophthalmitis was significantly greater with ofloxacin than with azithromycin. These findings provide a valuable addition to the ever-increasing pool of infor - mation on endophthalmitis prophylaxis after intravitreal injection, although further large-scale studies are required to provide definitive conclusions.
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Kaksifaasivirtauksen kuvaamiseen käytettävät mallit, ja menetelmät kaksifaasivirtauksen painehäviön määrittämiseksi kehittyvät yhä monimutkaisimmiksi. Höyrystinputkissa tapahtuvien painehäviöiden arvioinnin vaatiman laskennan suorittamiseksi tietokoneohjelman kehittäminen on välttämätöntä. Tässä työssä on kehitetty itsenäinen PC-ohjelma painehäviöiden arvioimiseksi pakotetulle konvektiovirtaukselle pystysuorissa höyrykattilan höyrystinputkissa. Veden ja vesihöyryn aineominaisuuksien laskentaan käytetään IAPWS-IF97 –yhtälökokoelmaa sekä muita tarvittavia IAPWS:n suosittelemia yhtälöitä. Höyrystinputkessa kulloinkin vallitsevan virtausmuodon määrittämiseen käytetään sovelluskelpoisia virtausmuotojen välisiä rajoja kuvaavia yhtälöitä. Ohjelmassa käytetään painehäviön määritykseen kirjallisuudessa julkaistuja yhtälöitä, virtausmuodosta riippuen, alijäähtyneelle virtaukselle, kupla-, tulppa- ja rengasvirtaukselle sekä tulistetun höyryn virtaukselle. Ohjelman laskemia painehäviöarvioita verrattiin kirjallisuudesta valittuihin mittaustuloksiin. Laskettujen painehäviöiden virhe vaihteli välillä –19.5 ja +23.9 %. Virheiden itseisarvojen keskiarvo oli 12.8 %.
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The in vivo accessibility of the chick embryo makes it a favoured model system for experimental developmental biology. Although the range of available techniques now extends to miss-expression of genes through in ovo electroporation, it remains difficult to knock out individual gene expression. Recently, the possibility of silencing gene expression by RNAi in chick embryos has been reported. However, published studies show only discrete quantitative differences in the expression of the endogenous targeted genes and unclear morphological alterations. To elucidate whether the tools currently available are adequate to silence gene expression sufficiently to produce a clear and specific null-like mutant phenotype, we have performed several experiments with different molecules that trigger RNAi: dsRNA, siRNA, and shRNA produced from a plasmid coexpressing green fluorescent protein as an internal marker. Focussing on fgf8 expression in the developing isthmus, we show that no morphological defects are observed, and that fgf8 expression is neither silenced in embryos microinjected with dsRNA nor in embryos microinjected and electroporated with a pool of siRNAs. Moreover, fgf8 expression was not significantly silenced in most isthmic cells transformed with a plasmid producing engineered shRNAs to fgf8. We also show that siRNA molecules do not spread significantly from cell to cell as reported for invertebrates, suggesting the existence of molecular differences between different model systems that may explain the different responses to RNAi. Although our results are basically in agreement with previously reported studies, we suggest, in contrast to them, that with currently available tools and techniques the number of cells in which fgf8 gene expression is decreased, if any, is not sufficient to generate a detectable mutant phenotype, thus making RNAi useless as a routine method for functional gene analysis in chick embryos.
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Adipose tissue (AT) is distributed as large differentiated masses, and smaller depots covering vessels, and organs, as well as interspersed within them. The differences between types and size of cells makes AT one of the most disperse and complex organs. Lipid storage is partly shared by other tissues such as muscle and liver. We intended to obtain an approximate estimation of the size of lipid reserves stored outside the main fat depots. Both male and female rats were made overweight by 4-weeks feeding of a cafeteria diet. Total lipid content was analyzed in brain, liver, gastrocnemius muscle, four white AT sites: subcutaneous, perigonadal, retroperitoneal and mesenteric, two brown AT sites (interscapular and perirenal) and in a pool of the rest of organs and tissues (after discarding gut contents). Organ lipid content was estimated and tabulated for each individual rat. Food intake was measured daily. There was a surprisingly high proportion of lipid not accounted for by the main macroscopic AT sites, even when brain, liver and BAT main sites were discounted. Muscle contained about 8% of body lipids, liver 1-1.4%, four white AT sites lipid 28-63% of body lipid, and the rest of the body (including muscle) 38-44%. There was a good correlation between AT lipid and body lipid, but lipid in"other organs" was highly correlated too with body lipid. Brain lipid was not. Irrespective of dietary intake, accumulation of body fat was uniform both for the main lipid storage and handling organs: large masses of AT (but also liver, muscle), as well as in the"rest" of tissues. These storage sites, in specialized (adipose) or not-specialized (liver, muscle) tissues reacted in parallel against a hyperlipidic diet challenge. We postulate that body lipid stores are handled and regulated coordinately, with a more centralized and overall mechanisms than usually assumed.
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The Rare Cancer Network (RCN) was formed in the early 1990's to create a global network that could pool knowledge and resources in the studies of rare malignancies whose infrequency prevented both their study with prospective clinical trials. To date, the RCN has initiated 74 studies resulting in 46 peer reviewed publications. The First International Symposium of the Rare Cancer Network took place in Nice in March of 2014. Status updates and proposals for new studies were heard for fifteen topics. Ongoing studies continue for cardiac sarcomas, thyroid cancers, glomus tumors, and adult medulloblastomas. New proposals were presented at the symposium for primary hepatic lymphoma, solitary fibrous tumors, Rosai-Dorfman disease, tumors of the ampulla of Vater, salivary gland tumors, anorectal melanoma, midline nuclear protein in testes carcinoma, pulmonary lymphoepithelioma-like carcinoma, adenoid cystic carcinoma of the trachea, osteosarcomas of the mandible, and extra-cranial hemangiopericytoma. This manuscript presents the abstracts of those proposals and updates on ongoing studies, as well a brief summary of the vision and future of the RCN.
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Työn päätavoite on selvittää kuinka erityisesti sähkön markkinahinnan ennustamiseen ja johdannaismarkkinoiden tietämykseen perustuva lyhyen tähtäimen sähköjohdannaisten hyödyntäminen tapahtuu teollisessa energianhallinnassa. Tätä aihetta lähestytään luomalla prosessi lyhyen tähtäimen sähköjohdannaisten hyödyntämiselle. Prosessi esitellään ja selvitetään aina lähtökohdista todelliseen kaupankäyntiin asti erillisen esimerkkitehtaan avulla.Lyhyen tähtäimen sähköjohdannaisten hyödyntäminen teollisessa energianhallinnassa perustuu pääosin tulevaisuuden odotuksiin sähkön markkinahinnan kehittymisestä sekä tehtaiden operatiiviseen tilanteeseen. Operatiiviseen tilanteeseen perustuva lyhyen tähtäimen sähköjohdannaisten kaupankäynti on pääasiassa pitkän tähtäimen suojausten sopeuttamista lyhyelle tähtäimelle sopivaksi.Hinnan ennustamisella on suuri rooli lyhyen tähtäimen sähköjohdannaisten hyödyntämisprosessissa. Työssä esitelty hinnan ennustamismalli on sopiva päivä- ja viikkotason Nord Poolin Elspot -systeemihinnan ennustamiseen. Elspot -systeemihinnan ennustamismalli on suunniteltu käytännönläheiseksi ja sen perustana ovat todelliset fysikaaliset ja mitattavat suureet. Futuurimarkkinatietämys on tarpeen lyhyen tähtäimen johdannaisia käytettäessä. Työssä tutkitaan yleisiä markkinoiden odotuksia ja futuurimarkkinoiden tietoisuuden kehittymistä koskien tulevaa vallitsevaa tilannetta. Työssä luodaan myös työkalu, mikä auttaa kaupan laatijaa muodostamaan suuntaa-antavat todennäköisyydet eri hintanäkemyksille ja paikallistamaan mahdolliset markkinoiden epätodennäköiset hintaodotukset.Kokemukset Elspot -systeemihinnan ennustamismallin soveltamisesta ovat lupaavia. Lisäksi havainnot futuurimarkkinoiden käyttäytymisestä Nord Poolissa ja muodostettu työkalu suuntaa-antavien todennäköisyyksien selvittämiseksi auttavat kaupan laatijaa päätöksenteossa. Lyhyen tähtäimen sähköjohdannaisten hyödyntäminen teollisessa energianhallinnassa on periaatteessa mahdollista esitellyn prosessin avulla, vaikka täydellinen käyttöönotto vaatisi vielä joitakin järjestelyjä. Keskittymällä tilanteisiin jotka työssä kuvatulla prosessilla ovat hoidettavissa, työssä määritellyllä menettelyllä on mahdollisuudet saavuttaa epäedullisen hintakehityksen riskin väheneminen ja parempi taloudellinen tulos teollisen energianhallinnan sähkökaupankäynnissä.
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Aim: Modelling species at the assemblage level is required to make effective forecast of global change impacts on diversity and ecosystem functioning. Community predictions may be achieved using macroecological properties of communities (MEM), or by stacking of individual species distribution models (S-SDMs). To obtain more realistic predictions of species assemblages, the SESAM framework suggests applying successive filters to the initial species source pool, by combining different modelling approaches and rules. Here we provide a first test of this framework in mountain grassland communities. Location: The western Swiss Alps. Methods: Two implementations of the SESAM framework were tested: a "Probability ranking" rule based on species richness predictions and rough probabilities from SDMs, and a "Trait range" rule that uses the predicted upper and lower bound of community-level distribution of three different functional traits (vegetative height, specific leaf area and seed mass) to constraint a pool of environmentally filtered species from binary SDMs predictions. Results: We showed that all independent constraints expectedly contributed to reduce species richness overprediction. Only the "Probability ranking" rule allowed slightly but significantly improving predictions of community composition. Main conclusion: We tested various ways to implement the SESAM framework by integrating macroecological constraints into S-SDM predictions, and report one that is able to improve compositional predictions. We discuss possible improvements, such as further improving the causality and precision of environmental predictors, using other assembly rules and testing other types of ecological or functional constraints.