926 resultados para basic solution in organic solvent


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Particle fluxes (including major components and grain size), and oceanographic parameters (near-bottom water temperature, current speed and suspended sediment concentration) were measured along the Cap de Creus submarine canyon in the Gulf of Lions (GoL; NW Mediterranean Sea) during two consecutive winter-spring periods (2009 2010 and 2010 2011). The comparison of data obtained with the measurements of meteorological and hydrological parameters (wind speed, turbulent heat flux, river discharge) have shown the important role of atmospheric forcings in transporting particulate matter through the submarine canyon and towards the deep sea. Indeed, atmospheric forcing during 2009 2010 and 2010 2011 winter months showed differences in both intensity and persistence that led to distinct oceanographic responses. Persistent dry northern winds caused strong heat losses (14.2 × 103 W m−2) in winter 2009 2010 that triggered a pronounced sea surface cooling compared to winter 2010 2011 (1.6 × 103 W m−2 lower). As a consequence, a large volume of dense shelf water formed in winter 2009 2010, which cascaded at high speed (up to ∼1 m s−1) down Cap de Creus Canyon as measured by a current-meter in the head of the canyon. The lower heat losses recorded in winter 2010 2011, together with an increased river discharge, resulted in lowered density waters over the shelf, thus preventing the formation and downslope transport of dense shelf water. High total mass fluxes (up to 84.9 g m−2 d−1) recorded in winter-spring 2009 2010 indicate that dense shelf water cascading resuspended and transported sediments at least down to the middle canyon. Sediment fluxes were lower (28.9 g m−2 d−1) under the quieter conditions of winter 2010 2011. The dominance of the lithogenic fraction in mass fluxes during the two winter-spring periods points to a resuspension origin for most of the particles transported down canyon. The variability in organic matter and opal contents relates to seasonally controlled inputs associated with the plankton spring bloom during March and April of both years.

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This report documents work undertaken in the demonstration of a low-cost Automatic Weight and Classification System (AWACS). An AWACS procurement specification and details of the results of the project are also included. The intent of the project is to support and encourage transferring research knowledge to state and local agencies and manufacturers through field demonstrations. Presently available, Weigh-in-Motion and Classification Systems are typically too expensive to permit the wide deployment necessary to obtain representative vehicle data. Piezo electric technology has been used in the United Kingdom and Europe and is believed to be the basic element in a low-cost AWACS. Low-cost systems have been installed at two sites, one in Portland Cement Concrete (PCC) pavement in Iowa and the other in Asphaltic Cement Concrete (ACC) pavement in Minnesota to provide experience with both types of pavement. The systems provide axle weights, gross vehicle weight, axle spacing, vehicle classification, vehicle speed, vehicle count, and time of arrival. In addition, system self-calibration and a method to predict contact tire pressure is included in the system design. The study has shown that in the PCC pavement, the AWACS is capable of meeting the needs of state and federal highway agencies, producing accuracies comparable to many current commercial WIM devices. This is being achieved at a procurement cost of substantially less than currently available equipment. In the ACC pavement the accuracies were less than those observed in the PCC pavement which is concluded to result from a low pavement rigidity at this site. Further work is needed to assess the AWACS performance at a range of sites in ACC pavements.

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A broad and simple method permitted halide ions in quaternary heteroaromatic and ammonium salts to be exchanged for a variety of anions using an anion exchange resin (A− form) in non-aqueous media. The anion loading of the AER (OH− form) was examined using two different anion sources, acids or ammonium salts, and changing the polarity of the solvents. The AER (A− form) method in organic solvents was then applied to several quaternary heteroaromatic salts and ILs, and the anion exchange proceeded in excellent to quantitative yields, concomitantly removing halide impurities. Relying on the hydrophobicity of the targeted ion pair for the counteranion swap, organic solvents with variable polarity were used, such as CH3OH, CH3CN and the dipolar nonhydroxylic solvent mixture CH3CN:CH2Cl2 (3:7) and the anion exchange was equally successful with both lipophilic cations and anions.

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Remote control systems are a very useful element to control and monitor devices quickly and easily. This paper proposes a new architecture for remote control of Android mobile devices, analyzing the different alternatives and seeking the optimal solution in each case. Although the area of remote control, in case of mobile devices, has been little explored, it may provide important advantages for testing software and hardware developments in several real devices. It can also allow an efficient management of various devices of different types, perform forensic security tasks, etc ... The main idea behind the proposed architecture was the design of a system to be used as a platform which provides the services needed to perform remote control of mobile devices. As a result of this research, a proof of concept was implemented. An Android application running a group of server programs on the device, connected to the network or USB interface, depending on availability. This servers can be controlled through a small client written in Java and runnable both on desktop and web systems.

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Activation of the Janus Kinase 2/Signal Transducer and Activator of Transcription 3 (JAK2/STAT3) pathway is known to play a key role in cardiogenesis and to afford cardioprotection against ischemia-reperfusion in adult. However, involvement of JAK2/STAT3 pathway and its interaction with other signaling pathways in developing heart transiently submitted to anoxia remains to be explored. Hearts isolated from 4-day-old chick embryos were submitted to anoxia (30 min) and reoxygenation (80 min) with or without the antioxidant MPG, the JAK2/STAT3 inhibitor AG490 or the PhosphoInositide-3-Kinase (PI3K)/Akt inhibitor LY-294002. Time course of phosphorylation of STAT3α(tyrosine705) and Reperfusion Injury Salvage Kinase (RISK) proteins [PI3K, Akt, Glycogen Synthase Kinase 3beta (GSK3beta), Extracellular signal-Regulated Kinase 2 (ERK2)] was determined in homogenate and in enriched nuclear and cytoplasmic fractions of the ventricle. STAT3 DNA-binding was determined. The chrono-, dromo- and inotropic disturbances were also investigated by electrocardiogram and mechanical recordings. Phosphorylation of STAT3α(tyr705) was increased by reoxygenation, reduced (~50%) by MPG or AG490 but not affected by LY-294002. STAT3 and GSK3beta were detected both in nuclear and cytoplasmic fractions while PI3K, Akt and ERK2 were restricted to cytoplasm. Reoxygenation led to nuclear accumulation of STAT3 but unexpectedly without DNA-binding. AG490 decreased the reoxygenation-induced phosphorylation of Akt and ERK2 and phosphorylation/inhibition of GSK3beta in the nucleus, exclusively. Inhibition of JAK2/STAT3 delayed recovery of atrial rate, worsened variability of cardiac cycle length and prolonged arrhythmias as compared to control hearts. Thus, besides its nuclear translocation without transcriptional activity, oxyradicals-activated STAT3α can rapidly interact with RISK proteins present in nucleus and cytoplasm, without dual interaction, and reduce the anoxia-reoxygenation-induced arrhythmias in the embryonic heart.

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The aim of this study was to find whether there were interprofessional differences in specific elements of communication with terminal cancer patients and decision-making processes that concern such patients. Given that interdisciplinary team work is one of the basic values in palliative care, if there are conflicting views between professions on such important issues it is most important to know about these and to understand them. A questionnaire utilized in an earlier survey of palliative care physicians and addressing their attitudes to and beliefs about specific elements of communication and decision making was sent to a sample of palliative care nurses working in the same regions, i.e. the French-speaking parts of Switzerland, Belgium and France. After a second mailing (reminder), 135 of the 163 questionnaires (83%) were returned. There was general agreement between nurses and physicians on questions dealing with perceptions of patients' knowledge of their diagnosis and stage of disease, patients' need for information, "do not resuscitate" orders and ethical principles in decision-making processes. Statistically significant, but small, differences between professional groups were only observed for a minority of the questions. Interprofessional differences in specific elements of communication with terminal cancer patients and decision-making processes affecting these patients were not so marked that they could be called "conflicting interprofessional views."

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BACKGROUND: Dried blood spots (DBS) sampling has gained popularity in the bioanalytical community as an alternative to conventional plasma sampling, as it provides numerous benefits in terms of sample collection and logistics. The aim of this work was to show that these advantages can be coupled with a simple and cost-effective sample pretreatment, with subsequent rapid LC-MS/MS analysis for quantitation of 15 benzodiazepines, six metabolites and three Z-drugs. For this purpose, a simplified offline procedure was developed that consisted of letting a 5-µl DBS infuse directly into 100 µl of MeOH, in a conventional LC vial. RESULTS: The parameters related to the DBS pretreatment, such as extraction time or internal standard addition, were investigated and optimized, demonstrating that passive infusion in a regular LC vial was sufficient to quantitatively extract the analytes of interest. The method was validated according to international criteria in the therapeutic concentration ranges of the selected compounds. CONCLUSION: The presented strategy proved to be efficient for the rapid analysis of the selected drugs. Indeed, the offline sample preparation was reduced to a minimum, using a small amount of organic solvent and consumables, without affecting the accuracy of the method. Thus, this approach enables simple and rapid DBS analysis, even when using a non-DBS-dedicated autosampler, while lowering the costs and environmental impact.

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The continuous wavelet transform is obtained as a maximumentropy solution of the corresponding inverse problem. It is well knownthat although a signal can be reconstructed from its wavelet transform,the expansion is not unique due to the redundancy of continuous wavelets.Hence, the inverse problem has no unique solution. If we want to recognizeone solution as "optimal", then an appropriate decision criterion hasto be adopted. We show here that the continuous wavelet transform is an"optimal" solution in a maximum entropy sense.

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Concerns have increased regarding the detection of endocrine-disrupting compounds in the effluents of sewage treatment plants (STPs). These compounds are able to disrupt normal function of the endocrine system of living organisms even at trace concentrations. Natural and synthetic steroid estrogens (SEs) are believed to be responsible for the majority of the endocrine-disrupting effects. Municipal sewage, the main source of SEs in the environment, is a complex mixture of a wide range of pollutants at concentrations much higher than those of SEs. Low concentrations of SEs in the presence of copollutants thus make their removal problematic. The main objectives of the present work were to study the potential of photocatalytic oxidation (PCO) to effectively treat SE-containing aqueous solutions and to identify the optimum conditions for such treatment. The results showed that SEs can be effectively degraded photocatalytically. Due to the adsorption properties of SEs on the TiO2 photocatalyst surface alkaline medium was found to be beneficial for SE oxidation despite the presence of co-pollutants in concentrations characteristic for the sanitary fraction of municipal sewage. The potential of PCO to selectively oxidise SEs was examined in the presence of copollutants of the sanitary fraction of sewage - urea, saccharose and human urine. The impact of ethanol, often used as a solvent in the preparation of SE stock solutions, was also studied and the results indicated the need to use organic solvent-free solutions for the study of SE behaviour. Photocatalytic oxidation of SEs appeared to be indifferent towards the presence of urea in concentrations commonly found in domestic sewage. The effect of other co-pollutants under consideration was far weaker than could be expected from their concentrations, which are from one hundred to a few thousands times higher than those of the SEs. Although higher concentrations can dramatically slow down the PCO of SEs, realistic concentrations of co-pollutants characteristic for the sanitary fraction of domestic sewage allowed selective removal of SEs. This indicates the potential of PCO to be a selective oxidation method for SE removal from the separate sanitary fraction of municipal sewage.

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In this letter, we obtain the Maximum LikelihoodEstimator of position in the framework of Global NavigationSatellite Systems. This theoretical result is the basis of a completelydifferent approach to the positioning problem, in contrastto the conventional two-steps position estimation, consistingof estimating the synchronization parameters of the in-viewsatellites and then performing a position estimation with thatinformation. To the authors’ knowledge, this is a novel approachwhich copes with signal fading and it mitigates multipath andjamming interferences. Besides, the concept of Position–basedSynchronization is introduced, which states that synchronizationparameters can be recovered from a user position estimation. Weprovide computer simulation results showing the robustness ofthe proposed approach in fading multipath channels. The RootMean Square Error performance of the proposed algorithm iscompared to those achieved with state-of-the-art synchronizationtechniques. A Sequential Monte–Carlo based method is used todeal with the multivariate optimization problem resulting fromthe ML solution in an iterative way.

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Massaräätälöinti on tärkeä osa nykyaikaista tuotestrategiaa. Massaräätälöinti mahdollistaa asiakaskohtaisesti muokattujen tuotteiden valmistuksen massatuotannon tehokkuudella. Massaräätälöinti edellyttää laajamittaista tietojärjestelmien hyväksikäyttöä, niin räätälöityjen tuotteiden mallinnuksessa, tuotteistuksessa kuin ylläpidossakin. Diplomityössä käsittelen taustatekijöitä jotka ovat johtaneet massaräätälöinnin syntyyn ja yleistymiseen. Käsittelyssä ovat myös erilaiset tavat toteuttaa massaräätälöintiä ja tietojärjestelmät jota tukevat massaräätälöintiä. Diplomityön empiirisessä osassa tarkastellaan Nokia Networksin tapaa toteuttaa massaräätälöintiä sekä esitellään tärkeimmät tätä tukevat järjestelmät. Empiirisen osan painopiste on kuitenkin hyvin vahvasti keskittynyt yhteen tuoterakenteiden osaan, joka on aiheuttanut haasteita Nokia Networksin massaräätälöintikonseptille. Tämä tuoterakenteen osa on valjastettu moneen erilaiseen käyttöön, mikä aiheuttaa ongelmia tietojärjestelmissä ja prosesseissa joihin se on vaikuttamassa. Työn tarkoituksena on kartoittaa kaikki ne ongelmat joita tämä tuoterakenteen osa aiheuttaa sulavalle massaräätälöinnin toteuttamiselle, niin yleisesti kuin järjestelmä- ja prosessimielessäkin. Työ on tehty osana laajamittaista projektia. Projektin tarkoituksena on kehittää uusi ja joustavampi ratkaisu tuoterakenteisiin, mandollistaen asiakaskohtaisten räätälöityjen tuotteiden valmistamisen, niin että se sopii Nokia Networksin järjestelmä sekä prosessi ympäristöön.

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The effects of the addition to sausage mix of tocopherols (200 mg/kg), a conventional starter culture with or without Staphylococcus carnosus, celery concentrate (CP) (0.23% and 0.46%), and two doses of nitrate (70 and 140 mg/kg expressed as NaNO(3)) on residual nitrate and nitrite amounts, instrumental CIE Lab color, tocol content, oxidative stability, and overall acceptability were studied in fermented dry-cured sausages after ripening and after storage. Nitrate doses were provided by nitrate-rich CP or a chemical grade source. The lower dose complies with the EU requirements governing the maximum for ingoing amounts in organic meat products. Tocopherol addition protected against oxidation, whereas the nitrate dose, nitrate source, or starter culture had little influence on secondary oxidation values. The residual nitrate and nitrite amounts found in the sausages with the lower nitrate dose were within EU-permitted limits for organic meat products and residual nitrate can be further reduced by the presence of the S. carnosus culture. Color measurements were not affected by the CP dose. Product consumer acceptability was not affected negatively by any of the factors studied. As the two nitrate sources behaved similarly for the parameters studied, CP is a useful alternative to chemical ingredients for organic dry-cured sausage production.

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Uusia keinoja kullan erottamiseksi malmista on etsitty viimeaikoina taloudellisista ja ympäristöllisistä syistä kautta maailman. Syanidointimenetelmä on hallinnut kullan talteenottoayli sata vuotta. Menetelmässä kulta liuotetaan laimeaan syanidiliuokseen, jostase otetaan talteen aktiivihiilen avulla. Syanidin käyttöä pyritään kuitenkin vähentämään sen myrkyllisyyden takia. Lisäksi nykyään louhitaan enenemässä määrin malmia, josta on hankala rikastaa kulta kustannustehokkaasti syanidia käyttäen. Kullan talteenottoa syanidi- ja kloridiliuoksesta on selvitetty kirjallisuuden avulla. Kullan kemiaan liuotuksen aikana on perehdytty ennen kullan talteenottoa aktiivihiilellä. Aktiivihiilen elinkaari kullan adsorbenttinaon käsitelty valmistuksesta hylkäämiseen mukaan lukien hiilen myrkyttyminen prosessissa ja regenerointi. Aktiivi-hiilen käyttäytyminen syanidi- ja kloridiliuoksessa on selvitetty erikseen. Kullan talteenottoa kuparipitoisista malmeista on käsitelty. Kullan talteenottoa kloridiliuoksesta aktiivihiiltä käyttäen on tutkittu kokeellisesti. Pääasialliset tutkimuskohteet ovat adsorption kinetiikka, kuparin vaikutus adsorptioon, aktiivihiilen vaikutus adsorptioonja adsorboituneiden metallien strippaus hiilestä selektiivisesti. Hapettavan stippauksen vaikutus kullan desorptioon hiilestä on tutkittu yksityiskohtaisesti. Kullan erotusmenetelmät kuparimalmista aktiivihiiltä käyttäen on selvitetty diplomityön tulosten pohjalta. Diplomityön keskeisten tulosten perusteella kulta ei välttämättä saostu aktiivihiilen pinnalle kloridiliuoksesta. Havainto varmistettiin ladattujen hiilipartikkelien pyyhkäisyelektronimikroskooppikuvista ja partikkeleille tehdyistä mikroanalyyseistä. Kullan pelkistyminen metalliseksi kullaksi aktiivihiilessä voitaneen välttää käyttämällä erittäin hapettavia olosuhteita. Aktiivihiili ilmeisesti hapettuu näissä olosuhteissa, mikä mahdollistaa kultakloridin adsorboitumisen hiileen.

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CONTEXT: Increased altruism, self-transcendence, and quests for meaning in life (MiL) have been found in palliative care (PC) patients and their families who experience the finiteness of life. Similar changes were observed in healthy subjects who were experimentally confronted with their mortality. OBJECTIVES: The study investigated how daily experiences of the transitoriness of life influence PC health care professionals' (HCPs) values, MiL, and religiousness. METHODS: In a cross-sectional study, the Schwartz Value Survey, the Schedule for Meaning in Life Evaluation, and the Idler Index of Religiosity were used to investigate personal values, MiL, and private religiousness. HCPs working in PC (confronted with death) were compared with a control group of HCPs working at maternity wards (MWs) using multivariate models. Differences were considered to be statistically significant at P < 0.05. RESULTS: Seventy PC- and 70 MW-HCPs took part in the study (response rate 74.0%). No differences between the groups were found in overall MiL satisfaction scores. PC-HCPs were significantly more religious than MW-HCPs; they listed spirituality and nature experience more often as areas in which they experience MiL. Furthermore, hedonism was more important for PC-HCPs, and they had higher scores in openness-to-change values (stimulation and self-direction). MW-HCPs were more likely to list family as a MiL area. They assigned more importance to health and scored higher in conservation values (conformity and security). Duration of professional experience did not influence these results. CONCLUSION: Basic differences in values, MiL, and religiousness between PC-HCPs and MW-HCPs might have influenced the choice of working environment because no effect of job duration was observed. Longitudinal research is needed to confirm this hypothesis.

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Pro gradu -tutkielman tavoitteena on selvittää, mikä on luottamuksen rooli B2B-asiakassuhteessa. Mitkä ovat B2B-suhteen ominaispiirteet, mikä on luottamuksen rooli ja luonne ja mikä on luottamuksen dynamiikka B2B-asiakassuhteessa. Tavoitteisiin on pyritty laadullisen tutkimuksen avulla. Aineisto kerättiin haastatteluilla ja analysointiin manuaalisesti teemoittain. Tutkimuksen tulokset osoittavat, että B2B-asiakassuhde on vaativa yhteistyömuoto, joka tarjoaa molemmille osapuolille hyötyjä sekä mahdollisuuksia kehittyä ja menestyä. Luottamus on suhteen ja menestyksellisen yhteistyön perusedellytys. Se perustuu hyvään mainee-seen, yhteiseen historiaan ja kokemuksiin ja sitä tarvitaan erityisesti viestinnässä, oppimisessa ja ongelmanratkaisussa. Henkilökohtaisten kontaktien ja partnereiden välisen henkilökemian lisäksi tehokkaimmat tavat rakentaa luottamusta ovat lupausten pitäminen jaerinomainen päivittäinen liiketoiminta asiakkaan kanssa.