955 resultados para METHOD-R


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Body size is a key determinant of metabolic rate, but logistical constraints have led to a paucity of energetics measurements from large water-breathing animals. As a result, estimating energy requirements of large fish generally relies on extrapolation of metabolic rate from individuals of lower body mass using allometric relationships that are notoriously variable. Swim-tunnel respirometry is the ‘gold standard’ for measuring active metabolic rates in water-breathing animals, yet previous data are entirely derived from body masses <10 kg – at least one order of magnitude lower than the body masses of many top-order marine predators. Here, we describe the design and testing of a new method for measuring metabolic rates of large water-breathing animals: a c. 26 000 L seagoing ‘mega-flume’ swim-tunnel respirometer. We measured the swimming metabolic rate of a 2·1-m, 36-kg zebra shark Stegostoma fasciatum within this new mega-flume and compared the results to data we collected from other S. fasciatum (3·8–47·7 kg body mass) swimming in static respirometers and previously published measurements of active metabolic rate measurements from other shark species. The mega-flume performed well during initial tests, with intra- and interspecific comparisons suggesting accurate metabolic rate measurements can be obtained with this new tool. Inclusion of our data showed that the scaling exponent of active metabolic rate with mass for sharks ranging from 0·13 to 47·7 kg was 0·79; a similar value to previous estimates for resting metabolic rates in smaller fishes. We describe the operation and usefulness of this new method in the context of our current uncertainties surrounding energy requirements of large water-breathing animals. We also highlight the sensitivity of mass-extrapolated energetic estimates in large aquatic animals and discuss the consequences for predicting ecosystem impacts such as trophic cascades.

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A modified UNIFAC–VISCO group contribution method was developed for the correlation and prediction of viscosity of ionic liquids as a function of temperature at 0.1 MPa. In this original approach, cations and anions were regarded as peculiar molecular groups. The significance of this approach comes from the ability to calculate the viscosity of mixtures of ionic liquids as well as pure ionic liquids. Binary interaction parameters for selected cations and anions were determined by fitting the experimental viscosity data available in literature for selected ionic liquids. The temperature dependence on the viscosity of the cations and anions were fitted to a Vogel–Fulcher–Tamman behavior. Binary interaction parameters and VFT type fitting parameters were then used to determine the viscosity of pure and mixtures of ionic liquids with different combinations of cations and anions to ensure the validity of the prediction method. Consequently, the viscosities of binary ionic liquid mixtures were then calculated by using this prediction method. In this work, the viscosity data of pure ionic liquids and of binary mixtures of ionic liquids are successfully calculated from 293.15 K to 363.15 K at 0.1 MPa. All calculated viscosity data showed excellent agreement with experimental data with a relative absolute average deviation lower than 1.7%.

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RNA interference (RNAi) has been shown to be a valuable tool to specifically target gene expression in a number of organisms becoming an indispensable weapon in the arsenal in functional genomics. In this study, we demonstrate that streptolysin-O (SLO) reversible permeabilisation is an efficient method to deliver small interfering RNAs (siRNAs) to hard-to-transfect human myeloma cell lines. We used published, pre-validated siRNAs for ERK2 and non-silencing siRNA control. We transfected siRNAs into human myeloma cell lines using SLO reversible permeabilisation method. Flow cytometry and western blot analysis were performed to assess the effect of SLO on transfection efficiency and ERK2 knockdown. These experiments demonstrate that SLO reversible permeabilisation method is an efficient and easy-to-use method to deliver siRNAs into human myeloma cell lines. Optimised SLO permeabilisation method showed to transfect >80% of JIM-3, H929, RPM18226 and U266 cells, with minimal effect on cell viability (<10%) and cell cycle. Equally important, SLO permeabilisation induced a substantial knockdown of ERK2 at the protein level. These studies demonstrate that reversible SLO permeabilisation can successfully be applied to hard-to-transfect human myeloma cell lines to effectively silence genes. (C) 2008 Published by Elsevier B.V.

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In this paper, Sr2Fe1.5Mo0.4Nb0.1O6-δ (SFMNb)-xSm0.2Ce0.8O2-δ (SDC) (x = 0, 20, 30, 40, 50 wt%) composite cathode materials were synthesized by a one-pot combustion method to improve the electrochemical performance of SFMNb cathode for intermediate temperature solid oxide fuel cells (IT-SOFCs). The fabrication of composite cathodes by adding SDC to SFMNb is conducive to providing extended electrochemical reaction zones for oxygen reduction reactions (ORR). X-ray diffraction (XRD) demonstrates that SFMNb is chemically compatible with SDC electrolytes at temperature up to 1100 °C. Scanning electron microscope (SEM) indicates that the SFMNb-SDC composite cathodes have a porous network nanostructure as well as the single phase SFMNb. The conductivity and thermal expansion coefficient of the composite cathodes decrease with the increased content of SDC, while the electrochemical impedance spectra (EIS) exhibits that SFMNb-40SDC composite cathode has optimal electrochemical performance with low polarization resistance (Rp) on the La0.9Sr0.1Ga0.8Mg0.2O3 electrolyte. The Rp of the SFMNb-40SDC composite cathode is about 0.047 Ω cm2 at 800 °C in air. A single cell with SFMNb-40SDC cathode also displays favorable discharge performance, whose maximum power density is 1.22 W cm-2 at 800 °C. All results indicate that SFMNb-40SDC composite material is a promising cathode candidate for IT-SOFCs.

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Cobalt-free composite cathodes consisting of Pr0.6Sr0.4FeO 3-δ -xCe0.9Pr0.1O 2-δ (PSFO-xCPO, x = 0-50 wt%) have been synthesized using a one-pot method. X-ray diffraction, scanning electron microscopy, thermal expansion coefficient, conductivity, and polarization resistance (R P ) have been used to characterize the PSFO-xCPO cathodes. Furthermore the discharge performance of the Ni-SSZ/SSZ/GDC/PSFO-xCPO cells has been measured. The experimental results indicate that the PSFO-xCPO composite materials fully consist of PSFO and CPO phases and posses a porous microstructure. The conductivity of PSFO-xCPO decreases with the increase of CPO content, but R P of PSFO-40CPO shows the smallest value amongst all the samples. The power density of single cells with a PSFO-40CPO composite cathode is significantly improved compared with that of the PSFO cathode, exhibiting 0.43, 0.75, 1.08 and 1.30 W cm-2 at 650, 700, 750 and 800 °C, respectively. In addition, single cells with the PSFO-40CPO composite cathode show a stable performance with no obvious degradation over 100 h when operating at 750 °C.

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The viscosity of ionic liquids (ILs) has been modeled as a function of temperature and at atmospheric pressure using a new method based on the UNIFAC–VISCO method. This model extends the calculations previously reported by our group (see Zhao et al. J. Chem. Eng. Data 2016, 61, 2160–2169) which used 154 experimental viscosity data points of 25 ionic liquids for regression of a set of binary interaction parameters and ion Vogel–Fulcher–Tammann (VFT) parameters. Discrepancies in the experimental data of the same IL affect the quality of the correlation and thus the development of the predictive method. In this work, mathematical gnostics was used to analyze the experimental data from different sources and recommend one set of reliable data for each IL. These recommended data (totally 819 data points) for 70 ILs were correlated using this model to obtain an extended set of binary interaction parameters and ion VFT parameters, with a regression accuracy of 1.4%. In addition, 966 experimental viscosity data points for 11 binary mixtures of ILs were collected from literature to establish this model. All the binary data consist of 128 training data points used for the optimization of binary interaction parameters and 838 test data points used for the comparison of the pure evaluated values. The relative average absolute deviation (RAAD) for training and test is 2.9% and 3.9%, respectively.

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Bakgrund: Employer Branding är ett relativt nytt begrepp som har börjat användas som en strategi inom Human Resource Management. Genom att utveckla ett Employer Brand kan or-ganisationer attrahera och behålla talangfull arbetskraft och på så vis säkra sin överlevnad. Det saknas emellertid forskning på hur Employer Branding kan användas i offentlig verksamhet för att attrahera den senaste generationen på arbetsmarknaden; Generation Y. Syfte: Öka förståelse för hur statliga myndigheter kan arbeta med Employer Branding för att attrahera Generation Y. Metod: Studien baseras på kvalitativ metod och har en fenomenologisk samt deduktiv forsk-ningsansats. Undersökningsdesignen var i form av en fallstudie. Nio semistrukturerade inter-vjuer har genomförts med respondenter på Bolagsverket, varav fyra intervjuer med personer som har inflytande över Employer Branding och fem med personer ur Generation Y. Teorier: "Employer Branding Predictive Model" Slutsatser: I studien visar att den statliga arbetsgivaren är attraktiv för Generation Y. Proble-matiken ligger i att det finns brister beträffande hur kommunikationen av arbetsgivarvarumärket ser ut externt. Utan en uttalad målgrupp och ett uttalat Employee Value Proposition blir den externa kommunikationen otydlig vilket minskar arbetsgivarens attraktionskraft hos potentiella arbetstagare. Attraktiviteten uppstår först när individen från Generation Y redan rekryterats in i organisationen.

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The need to steer economic development has always been great and as management model has the balanced scorecard has been popular since the mid- 1990s, mainly in the private sector but also in the municipal sector. The introduction of the balanced scorecard has been primarily to organizations to see more than economic dimensions. The Balanced Scorecard was originally a measurement system, and today it works more as a strategic instrument. In our study is a case study to evaluate a municipality and how they make use of the balanced scorecard as a tool for strategic and value-adding work in municipal activities. In the local business is it important that the organization adapts the balanced scorecard, so it fits on the basis that it is a politically driven organization, with mandates, committees and administrations. In our study, we used a qualitative method with a deductive approach. In the study, we have gathered information through a case study where we interviewed 7 people in leading positions. In our analysis and results section, we came to the conclusion that the municipality does not use the balanced scorecard correctly. We also found that the balanced scorecard as a tool for value creation and strategic planning does not work in a favorable way. In our study, we see difficulties with the implementation of the balanced scorecard. If the municipality has invested in implementing the balanced scorecard at all levels of the business so the municipality would be able to use it on one of the activities more adequately. When the municipality is a politically driven organization, it is important that vision alive and changing based on the conditions that reflect the outside world and the municipality in general. Looking at a vivid vision, goals and business ideas, it's balanced scorecard in line with how a balanced scorecard should look like. The municipality has a strategic plan in terms of staff and employees at large. In the study, we have seen that the strategic plan is not followed up in a good way and for the business favorably, the municipality chooses the easy way out for evaluation. Employee participation to changes and ongoing human resources management feels nonexistent. However, as has been the vision of creating empowered and motivated employees. In our conclusion, we describe how we in our study look at the use of the balanced scorecard in municipal operations. We can also discern that a balanced scorecard as a tool for value creation and strategic work is good if it is used properly. In the study, we have concluded that the municipality we have chosen to study should not use the balanced scorecard when you have not created the tools and platforms required for employees, civil servants and politicians to evaluate, monitor and create a living scorecard change over time. The study reveals major shortcomings in the implementation, evaluation and follow-up possibilities, and the consequence of this is that the balanced scorecard is not - 4 - preferable in municipal operations as a strategic instrument for value creation and long-term planning.

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Bakgrund: Goodwill är en omdebatterad immateriell tillgångspost. En nedskrivning ska enligt redovisningsstandarden IAS 36 baseras på bolagens framtida ekonomiska utveckling. Därmed kan en nedskrivning vara en indikation på hur bolagets ekonomiska framtid kommer att gestalta sig. Tidigare forskning visar att bolagsledningens subjektiva bedömningar kan leda till att nedskrivningens relevans kan ifrågasättas. Syfte: Enligt IFRS 3 och IAS 36 ska goodwill värderas till det framtida uppskattade värde som tillgången ska generera. Grundtanken med standarderna är att öka tillförlitligheten och relevansen för att bättre återspegla bolagens ekonomi i de finansiella rapporterna. Utifrån grundtanken bör en nedskrivning av goodwill vara en ledande indikator på framtida minskad lönsamhet. Vi avser därmed att undersöka om det finns ett samband mellan nedskrivning av goodwill och minskad framtida lönsamhet i svenska och finska börsnoterade bolag samt om det finns en skillnad mellan länderna när det gäller sambandet. Metod: Uppsatsen är baserad på en kvantitativ metod med en deduktiv ansats där sekundärdata hämtats från databas samt årsredovisningar. Informationen har samlats in för att därefter testas med regressionsanalyser. Slutsats: Studien kan inte styrka att standarden ger en bättre återspegling av bolagens ekonomi i de finansiella rapporterna. Resultatet visar att hanteringen av goodwill kan ske utifrån ett opportunistiskt beteende då nedskrivningen kan vara baserad på en redan realiserad försämring av goodwill istället för att vara baserad på framtida bedömningar. Resultatet antyder att tillsynen inte är harmoniserad inom EU, då det finns en signifikant skillnad mellan Sverige och Finland två år efter nedskrivningen. Studiens resultat kan användas till att ifrågasätta gällande standardens utformning.

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The results from the international surveys PISA 2011 and PIRLS 2011 shows that Swedish students have been deteriorating in reading comprehension. The main purpose of this literature study was to do a research review over different methods that intend to increase students’ reading comprehension by including students’ background knowledge. The method that is applied is a systematic literature study. The result of the study shows two bigger specializations of teaching methodics within reading comprehension, strategy oriented, and contextual teaching methods. The difference between these methods is hardly worth mentioning, but the contextual method is proven to be more efficient. Despite this the strategy oriented teaching method is to a great extent more researched. The result also shows that a new orientation within the research of reading comprehension is growing, where the focus is on the teachers’ knowledge and competence, instead of on teaching methods. A conclusion of the study is that all teaching methods that have been presented in the study develop the students’ reading comprehension in an effective way. It is also shown that the teacher has a big responsibility for the development within students’ reading comprehension.