454 resultados para disagreement


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The goal of this thesis was an experimental test of an effective theory of strong interactions at low energy, called Chiral Perturbation Theory (ChPT). Weak decays of kaon mesons provide such a test. In particular, K± → π±γγ decays are interesting because there is no tree-level O(p2) contribution in ChPT, and the leading contributions start at O(p4). At this order, these decays include one undetermined coupling constant, ĉ. Both the branching ratio and the spectrum shape of K± → π±γγ decays are sensitive to this parameter. O(p6) contributions to K± → π±γγ ChPT predict a 30-40% increase in the branching ratio. From the measurement of the branching ratio and spectrum shape of K± → π±γγ decays, it is possible to determine a model dependent value of ĉ and also to examine whether the O(p6) corrections are necessary and enough to explain the rate.About 40% of the data collected in the year 2003 by the NA48/2 experiment have been analyzed and 908 K± → π±γγ candidates with about 8% background contamination have been selected in the region with z = mγγ2/mK2 ≥ 0.2. Using 5,750,121 selected K± → π±π0 decays as normalization channel, a model independent differential branching ratio of K± → π±γγ has been measured to be:BR(K± → π±γγ, z ≥ 0.2) = (1.018 ± 0.038stat ± 0.039syst ± 0.004ext) ∙10-6. From the fit to the O(p6) ChPT prediction of the measured branching ratio and the shape of the z-spectrum, a value of ĉ = 1.54 ± 0.15stat ± 0.18syst has been extracted. Using the measured ĉ value and the O(p6) ChPT prediction, the branching ratio for z =mγγ2/mK2 <0.2 was computed and added to the measured result. The value obtained for the total branching ratio is:BR(K± → π±γγ) = (1.055 ± 0.038stat ± 0.039syst ± 0.004ext + 0.003ĉ -0.002ĉ) ∙10-6, where the last error reflects the uncertainty on ĉ.The branching ratio result presented here agrees with previous experimental results, improving the precision of the measurement by at least a factor of five. The precision on the ĉ measurement has been improved by approximately a factor of three. A slight disagreement with the O(p6) ChPT branching ratio prediction as a function of ĉ has been observed. This mightrnbe due to the possible existence of non-negligible terms not yet included in the theory. Within the scope of this thesis, η-η' mixing effects in O(p4) ChPT have also been measured.

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Purpose. Despite work-related stress is one of the most studied topic in organizational psychology, many aspects as for example the use of different measures (e.g. subjective and objective, qualitative and quantitative) are still under debate. According to this, in order to enhance knowledge concerning which factors and processes contribute to create healthy workplaces, this thesis is composed by four different studies aiming to understand: a) the role of relevant antecedents (e.g. leadership, job demands, work-family conflict, social support etc.) and outcomes (e.g. workplace phobia, absenteeism etc.) of work-related stress; and b) how to manage psychosocial risk factors in the workplace. The studies. The first study focused on how disagreement between supervisors and their employees on leadership style (transformational and transactional) could affect workers well-being and work team variables. The second and third study used both subjective and objective data in order to increase the quality of the reliability of the results gained. Particularly, the second study focused on job demand and its relationship with objective sickness leave. Findings showed that despite there is no direct relationship between these two variables, job demand affects work-family conflict, which in turn affect exhaustion, which leads to absenteeism. The third study analysed the role of a new concept never studied before in organizational settings (workplace phobia), as a health outcome in the JD-R model, demonstrating also its relationship with absenteeism. The last study highlighted the added value of using the mixed methods research approach in order to detect and analyse context-specific job demands which could affects workers’ health. Conclusion. The findings of this thesis answered both to open questions in the scientific literature and to the social request of managing psychosocial risk factors in the workplace in order to enhance workers well-being.

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Market manipulation is an illegal practice that enables a person can profit from practices that artificially raise or lower the prices of an instrument in the financial markets. Its prohibition is based on the 2003 Market Abuse Directive in the EU. The current market manipulation regime was broadly considered as a big success except for enforcement and supervisory inconsistencies in the Member States at the initial. A review of the market manipulation regime began at the end of 2007, which became quickly incorporated into the wider EU crisis-era reform program. A number of weaknesses of current regime have been identified, which include regulatory gaps caused by the development of trading venues and financial products, regulatory gaps concerning cross-border and cross-markets manipulation (particular commodity markets), legal uncertainty as a result of various implementation, and inefficient supervision and enforcement. On 12 June 2014, a new regulatory package of market abuse, Market Abuse Regulation and Directive on criminal sanctions for market abuse, has been adopted. And several changes will be made concerning the EU market manipulation regime. A wider scope of the regime and a new prohibition of attempted market manipulation will ensure the prevention of market manipulation at large. The AMPs will be subject to strict scrutiny of ESMA to reduce divergences in implementation. In order to enhance efficiency of supervision and enforcement, powers of national competent authorities will be strengthened, ESMA is imposed more power to settle disagreement between national regulators, and the administrative and criminal sanctioning regimes are both further harmonized. In addition, the protection of fundamental rights is stressed by the new market manipulation regime, and some measures are provided to guarantee its realization. Further, the success EU market manipulation regime could be of significant reference to China, helping China to refine its immature regime.

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Die theoretische und experimentelle Untersuchung von wasserstoffähnlichen Systemen hat in den letzten hundert Jahren immer wieder sowohl die experimentelle als auch die theoretische Physik entscheidend vorangebracht. Formulierung und Test der Quantenelektrodynamik (QED) standen und stehen in engen Zusammenhang mit der Untersuchung wasserstoffähnlicher Systeme. Gegenwärtig sind besonders wasserstoffähnliche Systeme schwerer Ionen von Interesse, um die QED in den extrem starken Feldern in Kernnähe zu testen. Laserspektroskopische Messungen der Hyperfeinstrukturaufspaltung des Grundzustandes bieten eine hohe Genauigkeit, ihre Interpretation wird jedoch durch die Unsicherheit in der Größe der Kernstruktureffekte erschwert. Beseitigt werden können diese durch die Kombination der Aufspaltung in wasserstoff- und lithiumähnlichen Ionen des gleichen Nuklids. In den letzten zwei Jahrzehnten scheiterten mehrere dadurch motivierte Versuche, den HFS-Übergang in lithiumähnlichen 209Bi80+ zu finden. Im Rahmen dieser Arbeit wurde kollineare Laserspektroskopie bei etwa 70% der Lichtgeschwindigkeit an 209Bi82+ und 209Bi80+ -Ionen im Experimentier- Speicherring an der GSI in Darmstadt durchgeführt. Dabei wurde der Übergang im lithiumähnlichen Bismut erstmals beobachtet und dessen Übergangswellenlänge zu 1554,74(74) nm bestimmt. Ein eigens für dieses Experiment optimiertes Fluoreszenz-Nachweissystem stellte dabei die entscheidende Verbesserung gegenüber den gescheiterten Vorgängerexperimenten dar. Der Wellenlängenfehler ist dominiert von der Unsicherheit der Ionengeschwindigkeit, die für die Transformation in das Ruhesystem der Ionen entscheidend ist. Für deren Bestimmung wurden drei Ansätze verfolgt: Die Geschwindigkeit wurde aus der Elektronenkühlerspannung bestimmt, aus dem Produkt von Orbitlänge und Umlauffrequenz und aus dem relativistischen Dopplereffekt unter Annahme der Korrektheit des früher bestimmten Überganges in wasserstoffähnlichen Bismut. Die Spannungskalibration des Elektronenkühlers wurde im Rahmen dieser Arbeit erstmals kritisch evaluiert und bislang unterschätzte systematische Unsicherheiten aufgezeigt, die derzeit einen aussagekräftigen QED-Test verhindern. Umgekehrt konnte unter Verwendung der QED-Berechnungen eine Ionengeschwindigkeit berechnet werden, die ein genaueres und konsistenteres Resultat für die Übergangswellenlängen beider Ionenspezies liefert. Daraus ergibt sich eine Diskrepanz zu dem früher bestimmten Wert des Überganges in wasserstoffähnlichen Bismut, die es weiter zu untersuchen gilt.

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The study of supermassive black hole (SMBH) accretion during their phase of activity (hence becoming active galactic nuclei, AGN), and its relation to the host-galaxy growth, requires large datasets of AGN, including a significant fraction of obscured sources. X-ray data are strategic in AGN selection, because at X-ray energies the contamination from non-active galaxies is far less significant than in optical/infrared surveys, and the selection of obscured AGN, including also a fraction of heavily obscured AGN, is much more effective. In this thesis, I present the results of the Chandra COSMOS Legacy survey, a 4.6 Ms X-ray survey covering the equatorial COSMOS area. The COSMOS Legacy depth (flux limit f=2x10^(-16) erg/s/cm^(-2) in the 0.5-2 keV band) is significantly better than that of other X-ray surveys on similar area, and represents the path for surveys with future facilities, like Athena and X-ray Surveyor. The final Chandra COSMOS Legacy catalog contains 4016 point-like sources, 97% of which with redshift. 65% of the sources are optically obscured and potentially caught in the phase of main BH growth. We used the sample of 174 Chandra COSMOS Legacy at z>3 to place constraints on the BH formation scenario. We found a significant disagreement between our space density and the predictions of a physical model of AGN activation through major-merger. This suggests that in our luminosity range the BH triggering through secular accretion is likely preferred to a major-merger triggering scenario. Thanks to its large statistics, the Chandra COSMOS Legacy dataset, combined with the other multiwavelength COSMOS catalogs, will be used to answer questions related to a large number of astrophysical topics, with particular focus on the SMBH accretion in different luminosity and redshift regimes.

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Changes in marine net primary productivity (PP) and export of particulate organic carbon (EP) are projected over the 21st century with four global coupled carbon cycle-climate models. These include representations of marine ecosystems and the carbon cycle of different structure and complexity. All four models show a decrease in global mean PP and EP between 2 and 20% by 2100 relative to preindustrial conditions, for the SRES A2 emission scenario. Two different regimes for productivity changes are consistently identified in all models. The first chain of mechanisms is dominant in the low- and mid-latitude ocean and in the North Atlantic: reduced input of macro-nutrients into the euphotic zone related to enhanced stratification, reduced mixed layer depth, and slowed circulation causes a decrease in macro-nutrient concentrations and in PP and EP. The second regime is projected for parts of the Southern Ocean: an alleviation of light and/or temperature limitation leads to an increase in PP and EP as productivity is fueled by a sustained nutrient input. A region of disagreement among the models is the Arctic, where three models project an increase in PP while one model projects a decrease. Projected changes in seasonal and interannual variability are modest in most regions. Regional model skill metrics are proposed to generate multi-model mean fields that show an improved skill in representing observation-based estimates compared to a simple multi-model average. Model results are compared to recent productivity projections with three different algorithms, usually applied to infer net primary production from satellite observations.

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Incorporation of enediynes into anticancer drugs remains an intriguing yet elusive strategy for the design of therapeutically active agents. Density functional theory was used to locate reactants, products, and transition states along the Bergman cyclization pathways connecting enediynes to reactive para-biradicals. Sum method correction to low-level calculations confirmed B3LYP/6-31G(d,p) as the method of choice in investigating enediynes. Herein described as MI:Sum, calculated reaction enthalpies differed from experiment by an average of 2.1 kcal·mol−1 (mean unsigned error). A combination of strain energy released across the reaction coordinate and the critical intramolecular distance between reacting diynes explains reactivity differences. Where experimental and calculated barrier heights are in disagreement, higher level multireference treatment of the enediynes confirms lower level estimates. Previous work concerning the chemically reactive fragment of esperamcin, MTC, is expanded to our model system MTC2.

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Shared Decision Making (SDM) is widely accepted as the preferred method for reaching treatment decisions in the oncology setting including those about clinical trial participation: however, there is some disagreement between researchers over the components of SDM. Specific standardized coding systems are needed to help overcome this difficulty.

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This study evaluated the correlation between three strip-type, colorimetric tests and two laboratory methods with respect to the analysis of salivary buffering. The strip-type tests were saliva-check buffer, Dentobuff strip and CRT(®) Buffer test. The laboratory methods included Ericsson's laboratory method and a monotone acid/base titration to create a reference scale for the salivary titratable acidity. Additionally, defined buffer solutions were prepared and tested to simulate the carbonate, phosphate and protein buffer systems of saliva. The correlation between the methods was analysed by the Spearman's rank test. Disagreement was detected between buffering capacity values obtained with three strip-type tests that was more pronounced in case of saliva samples with medium and low buffering capacities. All strip-type tests were able to assign the hydrogencarbonate, di-hydrogenphosphate and 0.1% protein buffer solutions to the correct buffer categories. However, at 0.6% total protein concentrations, none of the test systems worked accurately. Improvements are necessary for strip-type tests because of certain disagreement with the Ericsson's laboratory method and dependence on the protein content of saliva.

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Published opinions regarding the outcomes and complications in older patients have a broad spectrum and there is a disagreement whether surgery in older patients entails a higher risk. Therefore this study examines the risk of surgery for lumbar spinal stenosis relative to age in the pooled data set of the Spine Tango registry.

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Conflict has marked civilization from Biblical times to the present day. Each of us, with our different and competing interests, and our desires to pursue those interests, have over time wronged another person. Not surprisingly then, forgiveness is a concern of individuals and groups¿communities, countries, religious groups, races¿yet it is a complex idea that philosophers, theologians, political scientists, and psychologists have grappled with. Some have argued that forgiveness is a therapeutic means for overcoming guilt, pain, and anger. Forgiveness is often portrayed as a coping mechanism¿how often we hear the phrase, ¿forgive and forget,¿ as an arrangement to help two parties surmount the complications of disagreement. But forgiveness is not simply a modus vivendi; the ability to forgive and conversely to ask for forgiveness, is counted as an admirable trait and virtue. This essay will explore the nature of forgiveness, which in Christian dogma is often posited as an unqualified virtue. The secular world has appropriated the Christian notion of forgiveness as such a virtue¿but are there instances wherein offering forgiveness is morally inappropriate or dangerous? I will consider the situations in which forgiveness, understood in this essay as the overcoming of resentment, may not be a virtue¿when perhaps maintaining resentment is as virtuous, if not more virtuous, than forgiving. I will explain the various ethical frameworks involved in understanding forgiveness as a virtue, and the relationship between them. I will argue that within Divine Command Theory forgiveness is a virtue¿and thus morally right¿because God commands it. This ethical system has established forgiveness as unconditional, an idea which has been adopted into popular culture. With virtue ethics in mind, which holds virtues to be those traits which benefit the person who possesses them, contributing to the good life, I will argue unqualified forgiveness is not always a virtue, as it will not always benefit the victim. Because there is no way to avoid wrongdoing, humans are confronted with the question of forgiveness with every indiscretion. Its limits, its possibilities, its relationship to one¿s character¿forgiveness is a concern of all people at some time if for no other reason than the plain fact that the past cannot be undone. I will be evaluating the idea of forgiveness as a virtue, in contrast to its counterpart, resentment. How can forgiveness be a response to evil, a way to renounce resentment, and a means of creating a positive self-narrative? And what happens when a sense of moral responsibility is impossible to reconcile with the Christian (and now, secularized imperative of) forgiveness? Is it ever not virtuous to forgive? In an attempt to answer that question I will argue that there are indeed times when forgiveness is not a virtue, specifically: when forgiveness compromises one¿s own self-respect; when it is not compatible with respect for the moral community; and when the offender is unapologetic. The kind of offense I have in mind is a dehumanizing one, one that intends to diminish another person¿s worth or humanity. These are moral injuries, to which I will argue resentment is a better response than forgiveness when the three qualifications cannot be met.

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Model-based calibration of steady-state engine operation is commonly performed with highly parameterized empirical models that are accurate but not very robust, particularly when predicting highly nonlinear responses such as diesel smoke emissions. To address this problem, and to boost the accuracy of more robust non-parametric methods to the same level, GT-Power was used to transform the empirical model input space into multiple input spaces that simplified the input-output relationship and improved the accuracy and robustness of smoke predictions made by three commonly used empirical modeling methods: Multivariate Regression, Neural Networks and the k-Nearest Neighbor method. The availability of multiple input spaces allowed the development of two committee techniques: a 'Simple Committee' technique that used averaged predictions from a set of 10 pre-selected input spaces chosen by the training data and the "Minimum Variance Committee" technique where the input spaces for each prediction were chosen on the basis of disagreement between the three modeling methods. This latter technique equalized the performance of the three modeling methods. The successively increasing improvements resulting from the use of a single best transformed input space (Best Combination Technique), Simple Committee Technique and Minimum Variance Committee Technique were verified with hypothesis testing. The transformed input spaces were also shown to improve outlier detection and to improve k-Nearest Neighbor performance when predicting dynamic emissions with steady-state training data. An unexpected finding was that the benefits of input space transformation were unaffected by changes in the hardware or the calibration of the underlying GT-Power model.

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BACKGROUND: There is a lack of studies about how to proceed surgically in rare strabismus diseases. It was the aim of this study to inteview experienced German-speaking strabismologists about how they perform surgery in rare but also some frequent strabismic conditions. The focus was on the choice of the technique, the timing, and the dosage. METHOD: A validated questionnaire was sent to 11 experienced strabismus surgeons. It contained questions about the following topics: congenital fibrosis syndrome, Jaentsch-Brown syndrome, intermittent exotropia, maximum dosage for rectus muscle surgery, Kestenbaum surgery, sixth nerve palsy, heterophorias, myokymia of the superior oblique muscle, thyroid endocrine orbitopathy, dissociated vertical deviation, adjustable sutures, advancement of previously recessed rectus muscles, retroequatorial myopiexia, and congenital esotropia. RESULTS: Ten experts answered the questionnaire (91 %). There was a large consent for many topics. However, for many procedures there was disagreement about the dosage and the timing. Since some questions addressed rare diseases and many strabismologists use only certain types of surgical procedures, some questions could only be answered by a few surgeons. CONCLUSIONS: German-speaking strabismologist show a large consensus about the type of surgical procedure to use, but often disagree about the dosage and timing of the operation.

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OBJECTIVE: To study the inter-observer variation related to extraction of continuous and numerical rating scale data from trial reports for use in meta-analyses. DESIGN: Observer agreement study. DATA SOURCES: A random sample of 10 Cochrane reviews that presented a result as a standardised mean difference (SMD), the protocols for the reviews and the trial reports (n=45) were retrieved. DATA EXTRACTION: Five experienced methodologists and five PhD students independently extracted data from the trial reports for calculation of the first SMD result in each review. The observers did not have access to the reviews but to the protocols, where the relevant outcome was highlighted. The agreement was analysed at both trial and meta-analysis level, pairing the observers in all possible ways (45 pairs, yielding 2025 pairs of trials and 450 pairs of meta-analyses). Agreement was defined as SMDs that differed less than 0.1 in their point estimates or confidence intervals. RESULTS: The agreement was 53% at trial level and 31% at meta-analysis level. Including all pairs, the median disagreement was SMD=0.22 (interquartile range 0.07-0.61). The experts agreed somewhat more than the PhD students at trial level (61% v 46%), but not at meta-analysis level. Important reasons for disagreement were differences in selection of time points, scales, control groups, and type of calculations; whether to include a trial in the meta-analysis; and data extraction errors made by the observers. In 14 out of the 100 SMDs calculated at the meta-analysis level, individual observers reached different conclusions than the originally published review. CONCLUSIONS: Disagreements were common and often larger than the effect of commonly used treatments. Meta-analyses using SMDs are prone to observer variation and should be interpreted with caution. The reliability of meta-analyses might be improved by having more detailed review protocols, more than one observer, and statistical expertise.

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In Europe, a disagreement persists in the courts about the possibility of plaintiffs to request a domain name transfer in domain name disputes. In the last ten years, Slovak and Czech courts also produced some jurisprudence on this issue. Interestingly, the BGH’s influential opinion in the shell.de decision, which denied domain name transfer as an available remedy under German law back in 2002, wasn’t initially followed. To the contrary, several Slovak and Czech decisions of lower courts allowed a domain name transfer using two different legal bases. This seemingly settled case law was rejected a few months ago by the globtour.cz decision of the Czech Supreme Court, which refused domain name transfers for the time being