903 resultados para meta-analytical study


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The aim of this study is to contribute to the knowledge about learning in and through art related to pupils’ study processes developing clown characters in secondary school. The pre understanding of this qualitative piece of micro ethnographic research is that the elaboration of clown has openness to play, creative activity and imagination. The art form clown inspires and motivates. The clown character creates a kind and friendly atmosphere, calls upon smile, which promotes learning. It is an art form promoting deep and personal reflection and evoking questions regarding identity formation. The pre understanding finally is that existential themes are brought to articulation in the art form clown. The problem formulation for the hermeneutic phenomenological study is an exploration of the meaning potential of an arts educational work with clown from the pupils’ as well as the teacher’s perspective. The study elaborates the following research questions: 1.) How are the pupils staging themselves in the work with clown? a) How are they constructing the clown character? b) How do they reflect upon their construction? c) What are the characteristics of the working process in the elaboration of clown? 2.) What is characteristic of the teacher’s contribution to the arts educational work? 3.) What is characteristic of the meaning making in the elaboration of clown? One group of 21 pupils and their drama teacher in a Swedish secondary school in six workshops (each one 90 minutes) elaborating the clown theme is the group under study through video observation, interviews, students’ logs and drawings, teacher log and researcher’s field notes. The theoretical framework comprises three perspectives on clown: a perspective on the culture of carnival, a drama education perspective and a performance perspective. Through a content analysis of texts about clown a set of characteristics for the clown is used as analytical concepts in the subsequent analysis of the pupils’ working process when they create three clown characters: August, the white clown and the bag lady. The results are presented as fictive narratives built on the video observations and the interviews. The presentation is brought to even more condensation through poetic ethnographic writing of haiku poems by the researcher. This ethnographic writing is idiomatic to the art form under study, and can be seen as a metaphorical meta commentary to the narratives. As a main result the researcher has developed a model describing the different aspects of the clown characters and the meaning potential of the clown as learning regarding exploration of identity and elaboration of existential questions regarding life, loneliness, love, religion and death.

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Traditionally limestone has been used for the flue gas desulfurization in fluidized bed combustion. Recently, several studies have been carried out to examine the use of limestone in applications which enable the removal of carbon dioxide from the combustion gases, such as calcium looping technology and oxy-fuel combustion. In these processes interlinked limestone reactions occur but the reaction mechanisms and kinetics are not yet fully understood. To examine these phenomena, analytical and numerical models have been created. In this work, the limestone reactions were studied with aid of one-dimensional numerical particle model. The model describes a single limestone particle in the process as a function of time, the progress of the reactions and the mass and energy transfer in the particle. The model-based results were compared with experimental laboratory scale BFB results. It was observed that by increasing the temperature from 850 °C to 950 °C the calcination was enhanced but the sulfate conversion was no more improved. A higher sulfur dioxide concentration accelerated the sulfation reaction and based on the modeling, the sulfation is first order with respect to SO2. The reaction order of O2 seems to become zero at high oxygen concentrations.

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Information about capacity of transport and dispersion of soluble pollutants in natural streams are important in the management of water resources, especially in planning preventive measures to minimize the problems caused by accidental or intentional waste, in public health and economic activities that depend on the use of water. Considering this importance, this study aimed to develop a warning system for rivers, based on experimental techniques using tracers and analytical equations of one-dimensional transport of soluble pollutants conservative, to subsidizing the decision-making in the management of water resources. The system was development in JAVA programming language and MySQL database can predict the travel time of pollutants clouds from a point of eviction and graphically displays the temporal distribution of concentrations of passage clouds, in a particular location, downstream from the point of its launch.

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The fatigue failure of structures under fluctuating loads in fillet weld joints raises a demand to determine the parameters related to this type of loading. In this study, the stress distribution in the susceptible area of weld toe and weld root in fillet welded models analyzed by finite element method applying FEMAP software. To avoid the geometrical singularity on the path of analytical stress analysis in the toe and root area of a weld model the effective notch stress approach applied by which a proper fictitious rounding that mostly depend on the material of structure is applied. The models with different weld toe waving width and radius are analyzed while the flank angle of weld varied in 45 and 30 degrees. The processed results shows that the waving compare to the straight weld toe makes differences in the value of stress and consequently the stress concentration factor between the tip and depth of the waves in the weld toe which helps to protect the crack of propagation and gives enough time and tools to be informed of the crack initiation in the structure during the periodical observation of structure. In the weld root study the analyses among the models with the welding penetration percentage from non-penetration to the full-penetration shows a slightly increase in the root area stress value which comparing with the stiffening effect of penetration conclude that the half-penetration can make an optimization between the stress increase and stiffening effect of deep penetration.

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Following the current trend of companies in changing and developing their businesses from transactional approach to relationship and solution oriented approach has set new requirements to internal cooperation of companies too. The relationship between marketing and sales has been identified to be critical to company's success here, but surprisingly little is known about it. The purpose of this study was to deepen understanding of the relationship between sales and marketing in business-to-business sales from operative sales employees' perspectives in solution selling context. The aim was to develop an explorative analytical construction and framework of the interface. The study was conducted as a literature review and an empirical qualitative explorative single case study. The data was collected by conducting six thematic interviews with sales employees of the case company. Observing sales and marketing, written documents and other materials used in sales were used as secondary source of information. The data was analyzed using qualitative case study analysis methods. The findings of the study support previous research findings of the interface between marketing and sales but also bring new propositions as analytical framework to construct the interface. As such, the interface was found to be a multi-dimensional and complex dynamic construction. As results of this study, there was an exploratory framework constructed. The construction consists of three explorative contexts of the interface: internal context, relationship emphasizing context and solution selling context. These contexts are further divided into lower levels as an outcome of the analysis. In addition the identified contexts, there are also conceptual domains identified, which are common to all the contexts. The role of mutual, cross-functional knowledge creation was found to be central in the interface.

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Työn tarkoituksena oli kehittää analyyttinen erotusmenetelmä eräässä valmistusprosessissa käytettävän hapettavan aineen ja liuottimen välillä syntyvien reaktiotuotteiden tutkimiseen ja analysoimiseen. Lisäksi tarkoituksena oli tutkia prosessiolosuhteiden turvallisuutta. Kirjallisuusosassa käsitellään erilaisia orgaanisia peroksideja, niiden käyttötarkoituksia ja niiden käyttöön liittyviä huomioitavia asioita. Lisäksi tarkastellaan yleisimpiä analyysimenetelmiä, joita on käytetty erilaisten peroksidien analysoinnissa. Näitä analyysimenetelmiä on useimmiten käytetty nestemäisten näytteiden tutkimuksissa. Harvemmin on analysoitu kaasu- ja kiintoainenäytteitä. Kokeellisessa osassa kehitettiin kirjallisuuden perusteella peroksidiyhdisteille identifiointimenetelmä ja tutkittiin prosessin näytteet. Analyysimenetelmiksi valittiin iodometrinen titraus ja HPLC-UV-MS-menetelmä. Lisäksi käytettiin peroksidimittaukseen soveltuvia testiliuskoja. Tutkimus osoitti, että iodometrisen titrauksen ja testiliuskojen perusteella näytteissä oli vähäisiä määriä peroksideja viikon jälkeen peroksidilisäyksestä. HPLC-UV-MS-analyysien perusteella näytteiden analysointia häiritsi selluloosa, jota löytyi jokaisesta näytteestä.

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The flow of Bingham liquids through porous media has been studied. Experiments have been performed to determine the flow rate / pressure drop relationship for the flow of a grease of Binghamian rheological behavior through an array of rods of circular cross section. The yield stress and plastic viscosity of the grease have been determined with the aid of a controlled stress rotational rheometer. To investigate a wider range of the flow parameters, the mass and momentum conservation equations have been solved numerically, in conjunction with the generalized Newtonian constitutive law and the bi-viscosity model. The finite volume method has been employed to obtain the numerical solution. These numerical results also yielded a flow rate / pressure drop relationship, which is in very good agreement with the experimental results. A capillaric theory has been developed to determine an analytical relationship between the flow rate and pressure drop for flows of Bingham liquids through porous media. It is shown that the predictions of this theory are in good agreement with the experimental and numerical results.

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Because of the increased availability of different kind of business intelligence technologies and tools it can be easy to fall in illusion that new technologies will automatically solve the problems of data management and reporting of the company. The management is not only about management of technology but also the management of processes and people. This thesis is focusing more into traditional data management and performance management of production processes which both can be seen as a requirement for long lasting development. Also some of the operative BI solutions are considered in the ideal state of reporting system. The objectives of this study are to examine what requirements effective performance management of production processes have for data management and reporting of the company and to see how they are effecting on the efficiency of it. The research is executed as a theoretical literary research about the subjects and as a qualitative case study about reporting development project of Finnsugar Ltd. The case study is examined through theoretical frameworks and by the active participant observation. To get a better picture about the ideal state of reporting system simple investment calculations are performed. According to the results of the research, requirements for effective performance management of production processes are automation in the collection of data, integration of operative databases, usage of efficient data management technologies like ETL (Extract, Transform, Load) processes, data warehouse (DW) and Online Analytical Processing (OLAP) and efficient management of processes, data and roles.

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Finland’s rural landscape has gone through remarkable changes from the 1950’s, due to agricultural developments. Changed farming practices have influenced especially traditional landscape management, and modifications in the arable land structure and grasslands transitions are notable. The review of the previous studies reveal the importance of the rural landscape composition and structure to species and landscape diversity, whereas including the relevance in presence of the open ditches, size of the field and meadow patches, topology of the natural and agricultural landscape. This land-change study includes applying remote sensed data from two time series and empirical geospatial analysis in Geographic Information Systems (GIS). The aims of this retrospective research is to detect agricultural landscape use and land cover change (LULCC) dynamics and discuss the consequences of agricultural intensification to landscape structure covering from the aspects of landscape ecology. Measurements of LULC are derived directly from pre-processed aerial images by a variety of analytical procedures, including statistical methods and image interpretation. The methodological challenges are confronted in the process of landscape classification and combining change detection approaches with landscape indices. Particular importance is paid on detecting agricultural landscape features at a small scale, demanding comprehensive understanding of such agroecosystems. Topological properties of the classified arable land and valley are determined in order to provide insight and emphasize the aspect the field edges in the agricultural landscape as important habitat. Change detection dynamics are presented with change matrix and additional calculations of gain, loss, swap, net change, change rate and tendencies are made. Transition’s possibility is computed following Markov’s probability model and presented with matrix, as well. Thesis’s spatial aspect is revealed with illustrative maps providing knowledge of location of the classified landscape categories and location of the dynamics of the changes occurred. It was assured that in Rekijoki valley’s landscape, remarkable changes in landscape has occurred. Landscape diversity has been strongly influenced by modern agricultural landscape change, as NP of open ditches has decreased and the MPS of the arable plot has decreased. Overall change in the diversity of the landscape is determined with the decrease of SHDI. Valley landscape considered as traditional land use area has experienced major transitional changes, as meadows class has lost almost one third of the area due to afforestation. Also, remarkable transitions have occurred from forest to meadow and arable land to built area. Boundaries measurement between modern and traditional landscape has indicated noticeable proportional increase in arable land-forest edge type and decrease in arable land-meadow edge type. Probability calculations predict higher future changes for traditional landscape, but also for arable land turning into built area.

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Cardiac troponin (cTn) I and T are the recommended biomarkers for the diagnosis and risk stratification of patients with suspected acute coronary syndrome (ACS), a major cause of cardiovascular death and disability worldwide. It has recently been demonstrated that cTn-specific autoantibodies (cTnAAb) can negatively interfere with cTnI detection by immunoassays to the extent that cTnAAb-positive patients may be falsely designated as cTnI-negative. The aim of this thesis was to develop and optimize immunoassays for the detection of both cTnI and cTnAAb, which would eventually enable exploring the clinical impact of these autoantibodies on cTnI testing and subsequent patient management. The extent of cTnAAb interference in different cTnI assay configurations and the molecular characteristics of cTnAAbs were investigated in publications I and II, respectively. The findings showed that cTnI midfragment targeting immunoassays used predominantly in clinical practice are affected by cTnAAb interference which can be circumvented by using a novel 3+1-type assay design with three capture antibodies against the N-terminus, midfragment and C-terminus and one tracer antibody against the C-terminus. The use of this assay configuration was further supported by the epitope specificity study, which showed that although the midfragment is most commonly targeted by cTnAAbs, the interference basically encompasses the whole molecule, and there may be remarkable individual variation at the affected sites. In publications III and IV, all the data obtained in previous studies were utilized to develop an improved version of an existing cTnAAb assay and a sensitive cTnI assay free of this specific analytical interference. The results of the thesis showed that approximately one in 10 patients with suspected ACS have detectable amounts of cTnAAbs in their circulation and that cTnAAbs can inhibit cTnI determination when targeted against the binding sites of assay antibodies used in its immunological detection. In the light of these observations, the risk of clinical misclassification caused by the presence of cTnAAbs remains a valid and reasonable concern. Because the titers, affinities and epitope specificities of cTnAAbs and the concentration of endogenous cTnI determine the final effect of circulating cTnAAbs, appropriately sized studies on their clinical significance are warranted. The new cTnI and cTnAAb assays could serve as analytical tools for establishing the impact of cTnAAbs on cTnI testing and also for unraveling the etiology of cTn-related autoimmune responses.

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The aim of the present study was to compare the efficacy of chemotherapy and support treatment in patients with advanced non-resectable gastric cancer in a systematic review and meta-analysis of randomized clinical trials that included a comparison of chemotherapy and support care treatment in patients diagnosed with gastric adenocarcinoma, regardless of their age, gender or place of treatment. The search strategy was based on the criteria of the Cochrane Base, using the following key words: 1) randomized clinical trials and antineoplastic combined therapy or gastrointestinal neoplasm, 2) stomach neoplasm and drug therapy, 3) clinical trial and multi-modality therapy, 4) stomach neoplasm and drug therapy or quality of life, 5) double-blind method or clinical trial. The search was carried out using the Cochrane, Medline and Lilacs databases. Five studies fulfilled the inclusion criteria, for a total of 390 participants, 208 (53%) receiving chemotherapy, 182 (47%) receiving support care treatment and 6 losses (1.6%). The 1-year survival rate was 8% for support care and 20% for chemotherapy (RR = 2.14, 95% CI = 1.00-4.57, P = 0.05); 30% of the patients in the chemotherapy group and 12% in the support care group attained a 6-month symptom-free period (RR = 2.33, 95% CI = 1.41-3.87, P < 0.01). Quality of life evaluated after 4 months was significantly better for the chemotherapy patients (34%; RR = 2.07, 95% CI = 1.31-3.28, P < 0.01) with tumor mass reduction (RR = 3.32, 95% CI = 0.77-14.24, P = 0.1). Chemotherapy increased the 1-year survival rate of the patients and provided a longer symptom-free period of 6 months and an improvement in quality of life.

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Thin-film photovoltaic solar cells based on the Cu(In1−xGax)Se2 (CIGS) alloys have attracted more and more attention due to their large optical absorption coefficient, long term stability, low cost, and high efficiency. Modern theoretical studies of this material with first-principles calculations can provide accurate description of the electronic structure and yield results in close agreement with experimental values, but takes a large amount of calculation time. In this work, we use first-principles calculations based on the computationally affordable meta- generalized gradient approximation of the density-functional theory to investigate electronic and structural properties of the CIGS alloys. We report on the simulation of the lattice parameters and band gaps, as a function of chemical composition. The obtained results were found to be in a good agreement with the available experimental data.

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We assessed the efficacy and tolerability of the augmentation of antidepressants (ATDs) with atypical antipsychotics (AAPs) to treat patients with major depressive disorder. A retrograde study to identify relevant patient data included databases of PubMed, EMBASE, Cochrane Central Register of Controlled Trials, and Database of Abstracts of Reviews of Effects. Data from 17 trials, involving 3807 participants, were identified. The remission rate (RR) and overall response rate (ORR) of adjunctive treatment with AAPs were significantly higher than placebo treatment: RR=1.90 (95%CI=1.61-2.23, z=7.74, P<0.00001) and ORR=1.68 (95%CI=1.45-1.94, z=7.07, P<0.00001). We found that the short-term (4 weeks) treatment [ORR=1.70 (95%CI=0.98-2.95, Z=1.89, P=0.06)] was significantly different from the long-term (6-12 weeks) treatment [ORR=1.68 (95%CI=1.45-1.94, z=7.07, P<0.00001)]. No significant difference in ORR was observed between groups with or without sedative drugs. The discontinuation rate due to adverse effects was higher for adjunctive treatment with AAPs: ORR=3.32 (95%CI=2.35-4.70, z=6.78, P<0.00001). These results demonstrate that the augmentation of ATDs with AAPs (olanzapine, quetiapine, aripiprazole, and risperidone) was more effective than a placebo in improving response and remission rates, although associated with a higher discontinuation rate due to adverse effects.

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Necrotizing enterocolitis (NEC) is one of the most common acquired diseases of the gastrointestinal tract in preterm infants. Some randomized, controlled trials (RCTs) have indicated that probiotics may potentially lower the incidence of NEC and mortality. However, debate still remains about the safety of probiotics and their influence on normal infant growth. We performed this meta-analysis to assess the safety and benefits of probiotic supplementation in preterm infants. We searched in PubMed, Embase, and Cochrane databases for English references, and in Wanfang, VIP, and CNKI databases for Chinese references. Ultimately, 27 RCTs (including 9 Chinese articles) were incorporated into this meta-analysis. Relative risk (RR) and weighted mean difference (WMD) were calculated using a random-effects or fixed-effects model, depending on the data type and heterogeneity. A total of 6655 preterm infants, including the probiotic group (n=3298) and the placebo group (n=3357), were eligible for inclusion in this meta-analysis. For Bell stage ≥I and gestational age <37 weeks, risk of NEC incidence was significantly lower in the probiotic group [RR=0.35, 95% confidence interval (CI)=0.27-0.44, P<0.00001]. For Bell stage ≥II or gestational age <34 weeks, there were likewise significant differences between the probiotic and placebo groups concerning NEC incidence (RR=0.34, 95%CI=0.25-0.48, P<0.00001; and RR=0.39, 95%CI=0.27-0.56, P<0.00001). Risk of death was significantly reduced in the probiotic group (RR=0.58, 95%CI=0.46-0.75, P<0.0001). In contrast, there was no significant difference concerning the risk of sepsis (RR=0.94, 95%CI=0.83-1.06, P=0.31). With respect to weight gain and the age at which infants reached full feeds, no significant differences were found between the probiotic and placebo groups (WMD=1.07, 95%CI=−0.21-2.34, P=0.10; and WMD=−1.66, 95%CI=−3.6-0.27, P=0.09). This meta-analysis has shown that, regardless of gestational age and NEC stage, probiotic supplementation could significantly reduce the risk of NEC in preterm infants. Analysis also indicated that such supplementation did not increase the incidence risk of sepsis or of mortality. Finally, the study showed that probiotic supplementation may have no adverse effect on normal feeding and growth.

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We investigated the diagnostic value of the apparent diffusion coefficient (ADC) and fractional anisotropy (FA) of magnetic resonance diffusion tensor imaging (DTI) in patients with spinal cord compression (SCC) using a meta-analysis framework. Multiple scientific literature databases were exhaustively searched to identify articles relevant to this study. Mean values and standardized mean differences (SMDs) were calculated for the ADC and FA in normal and diseased tissues. The STATA version 12.0 software was used for statistical analysis. Of the 41 articles initially retrieved through database searches, 11 case-control studies were eligible for the meta-analysis and contained a combined total of 645 human subjects (394 patients with SCC and 251 healthy controls). All 11 studies reported data on FA, and 9 contained data related to the ADC. The combined SMDs of the ADC and FA showed that the ADC was significantly higher and the FA was lower in patients with SCC than in healthy controls. Subgroup analysis based on the b value showed higher ADCs in patients with SCC than in healthy controls at b values of both ≤500 and >500 s/mm2. In summary, the main findings of this meta-analysis revealed an increased ADC and decreased FA in patients with SCC, indicating that DTI is an important diagnostic imaging tool to assess patients suspected to have SCC.