410 research outputs found
Reconsidering the future of Eastern Europe: The case of Czecho-Slovakia
Economic Reform;economic systems
The Integrand Reduction of One- and Two-Loop Scattering Amplitudes
The integrand-level methods for the reduction of scattering amplitudes are
well-established techniques, which have already proven their effectiveness in
several applications at one-loop. In addition to the automation and refinement
of tools for one-loop calculations, during the past year we observed very
interesting progress in developing new techniques for amplitudes at two- and
higher-loops, based on similar principles. In this presentation, we review the
main features of integrand-level approaches with a particular focus on
algebraic techniques, such as Laurent series expansion which we used to improve
the one-loop reduction, and multivariate polynomial division which unveils the
structure of multi-loop amplitudes.Comment: 7 pages, v2: fixed typos, added references. Presented at "Loops and
Legs in Quantum Field Theory", Wernigerode, Germany, 15-20 April 201
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Inauthenticity and self-deception in Heidegger's Being and Time in relation to psychotherapy
This dissertation examines and clarifies Heidegger's contribution to our understanding of the important issues of self-deception and inauthenticity in psychotherapy. After some preliminary remarks on the concepts of inauthenticity and self-deception the first part of the dissertation explores Heidegger's fundamental ontology as detailed in Being and rime. basein's temporal nature and its relationship to death are considered in the context of the central concept of Care (Sorge) and its basic structures of thrownness (Geworfenheit), falling (verfallen) and existence (Existenz). This leads to a discussion of the existentials of disposition (Befindlichkeit), anxiety (Angst), understanding (verstehen)and discourse (Rede). After this preliminary exposition Heidegger's views on inauthenticity (Uneigentlichkeit) and authenticity (Eigentlichkeit) are explored, with a central focus on fallenness (verfallen) and its manifestations of idle talk (Gerede), curiosity (Neugier), ambiguity (Zweideutigkeit) and self-forgetting (selbstvergessen). Now the scene is set for an investigation of Heidegger's views on how inauthenticity is overcome and the notion of truth (Wahrheit), anxiety (Angst), call of conscience (6ewissenruf) and resoluteness (Entschluss) are studied in some detail. This leads to a description of authentic ways of being in a situation (Situation), being-towards-death (Sein zum Tode), the moment of vision (Augenblick) and repetition (Wiederholung). A full summary of Heidegger's ideas is given before a critique is formulated in light of Sartre's views, Fingarettes contribution and Heidegger's later work. It emerges that there is no place for a theory of self-deception in Heidegger. His descriptions of inauthenticity and forgetting show untruth to be a matter of alienation (Entfremdung) and closing off (verschliessen) rather than a matter of deceit. The thesis shows the significance of this alternative point of view. It is argued that Heidegger's objective for Dasein is to have vision, which means to be capable of both authentic, owned and engaged ways of existing as well as inauthentic, disowned and disengaged ways of existing. In final analysis the challenge of human existence for Heidegger is about being true to life rather than being true to self. Being true to life is inevitably about the equiprimordiality and equality of both inauthentic and authentic ways of being. To be loyal to existence therefore involves increasing transparency and openness to different modes of being. The thesis' orginal contribution is to show that this is a sound and new objective for existential psychotherapy. At the same time Sartres and Fingarette s perspectives on self-deception highlight Heidegger's failure to address the issue of self-deception directly. This is shown to be due mostly to Heidegger's lack of focus on ontic issues, his refusal to consider a moral and ethical dimension to his work and his replacement of a theory of self with a description of Daseins world relations. While this is in some ways a strength and an original position that allows us to view human existence from a new perspective, it leaves doubt about what Heidegger could have made of the ontic issues raised by applying his ideas in counselling and psychotherapy. The thesis takes Heidegger's ontological theory to a new, ontic dimension and a practical and concrete application. Heidegger himself suggested in the Zollikon seminars that his thought should be so applied and the final part of the thesis is constituted by my published work, which has been dedicated to this project. The three books in which this application is described are enclosed together with the philosophical part of the dissertation and they are each briefly discussed in light of the argument about inauthenticity and self-deception. It is shown how the ontic realities of psychotherapy place new demands on Heidegger's thinking whilst Heidegger's thinking at the same time provides a challenging basis for therapeutic clarity about human existence
NLO QCD corrections to the production of Higgs plus two jets at the LHC
We present the calculation of the NLO QCD corrections to the associated
production of a Higgs boson and two jets, in the infinite top-mass limit. We
discuss the technical details of the computation and we show the numerical
impact of the radiative corrections on several observables at the LHC. The
results are obtained by using a fully automated framework for fixed order NLO
QCD calculations based on the interplay of the packages GoSam and Sherpa. The
evaluation of the virtual corrections constitutes an application of the
d-dimensional integrand-level reduction to theories with higher dimensional
operators. We also present first results for the one-loop matrix elements of
the partonic processes with a quark-pair in the final state, which enter the
hadronic production of a Higgs boson together with three jets in the infinite
top-mass approximation.Comment: 9 pages, 7 figures, references added, published in Phys.Lett.
Automated one-loop calculations with GoSam 2.0
We present the version 2.0 of the program GoSam, which is a public program
package to compute one-loop corrections to multi-particle processes. The
extended version of the "Binoth-Les-Houches-Accord" interface to Monte Carlo
programs is also implemented. This allows a large flexibility regarding the
combination of the code with various Monte Carlo programs to produce fully
differential NLO results, including the possibility of parton showering and
hadronisation. We describe the new features of the code and illustrate the wide
range of applicability for multi-particle processes at NLO, both within and
beyond the Standard Model.Comment: 9 pages, talk given at the conference "Loops and Legs in Quantum
Field Theory", Weimar, Germany, April 201
GoSam-2.0: a tool for automated one-loop calculations within the Standard Model and beyond
We present the version 2.0 of the program package GoSam for the automated
calculation of one-loop amplitudes. GoSam is devised to compute one-loop QCD
and/or electroweak corrections to multi-particle processes within and beyond
the Standard Model. The new code contains improvements in the generation and in
the reduction of the amplitudes, performs better in computing time and
numerical accuracy, and has an extended range of applicability. The extended
version of the "Binoth-Les-Houches-Accord" interface to Monte Carlo programs is
also implemented. We give a detailed description of installation and usage of
the code, and illustrate the new features in dedicated examples.Comment: replaced by published version and reference adde
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Existential uncertainty in health care: A concept analysis
RATIONALE, AIMS AND OBJECTIVES: According to an influential taxonomy of varieties of uncertainty in health care, existential uncertainty is a key aspect of uncertainty for patients. Although the term "existential uncertainty" appears across a number of disciplines in the research literature, its use is diffuse and inconsistent. To date there has not been a systematic attempt to define it. The aim of this study is to generate a theoretically-informed conceptualisation of existential uncertainty within the context of an established taxonomy.
METHOD: Existential uncertainty was subjected to a concept analysis, which drew on existing uses of the term across multiple disciplines as well as insights from uncertainty theory more broadly and from the existential therapy literature to generate a tentative definition of the concept. Antecedents, consequences, and empirical referents of existential uncertainty were also identified. A model case was described as well as a borderline case and a related case in order to illustrate and delineate the concept.
RESULTS: Existential uncertainty is conceptualised as an awareness of the undetermined but finite nature of one's own being-in-the-world, concerned primarily with identity, meaning, and choice. This awareness is fundamental and ineradicable, and manifests at different levels of consciousness.
CONCLUSION: Humans rely on identity, worldview, and a sense of meaning in life as ways of managing the ineradicable uncertainty of our being-in-the-world, and these can be challenged by a serious diagnosis. It is important that medical professionals acknowledge issues around existential uncertainty as well as issues around scientific uncertainty, and recognise when patients might be struggling with these. Further research is required to identify ways of measuring existential uncertainty and to develop appropriate interventions, but it is hoped that this conceptualisation provides a useful first step towards that goal
Using second harmonic generation to predict patient outcome in solid tumors
Abstract
Background
Over-treatment of estrogen receptor positive (ER+), lymph node-negative (LNN) breast cancer patients with chemotherapy is a pressing clinical problem that can be addressed by improving techniques to predict tumor metastatic potential. Here we demonstrate that analysis of second harmonic generation (SHG) emission direction in primary tumor biopsies can provide prognostic information about the metastatic outcome of ER+, LNN breast cancer, as well as stage 1 colorectal adenocarcinoma.
Methods
SHG is an optical signal produced by fibrillar collagen. The ratio of the forward-to-backward emitted SHG signals (F/B) is sensitive to changes in structure of individual collagen fibers. F/B from excised primary tumor tissue was measured in a retrospective study of LNN breast cancer patients who had received no adjuvant systemic therapy and related to metastasis-free survival (MFS) and overall survival (OS) rates. In addition, F/B was studied for its association with the length of progression-free survival (PFS) in a subgroup of ER+ patients who received tamoxifen as first-line treatment for recurrent disease, and for its relation with OS in stage I colorectal and stage 1 lung adenocarcinoma patients.
Results
In 125 ER+, but not in 96 ER-negative (ER-), LNN breast cancer patients an increased F/B was significantly associated with a favorable MFS and OS (log rank trend for MFS: p = 0.004 and for OS: p = 0.03). On the other hand, an increased F/B was associated with shorter PFS in 60 ER+ recurrent breast cancer patients treated with tamoxifen (log rank trend p = 0.02). In stage I colorectal adenocarcinoma, an increased F/B was significantly related to poor OS (log rank trend p = 0.03), however this relationship was not statistically significant in stage I lung adenocarcinoma.
Conclusion
Within ER+, LNN breast cancer specimens the F/B can stratify patients based upon their potential for tumor aggressiveness. This offers a “matrix-focused” method to predict metastatic outcome that is complementary to genomic “cell-focused” methods. In combination, this and other methods may contribute to improved metastatic prediction, and hence may help to reduce patient over-treatment.http://deepblue.lib.umich.edu/bitstream/2027.42/116036/1/12885_2015_Article_1911.pd
The supplemental value of mammographic screening over breast MRI alone in BRCA2 mutation carriers
Purpose: BRCA2 mutation carriers are offered annual breast screening with MRI and mammography. The aim of this study was to investigate the supplemental value of mammographic screening over MRI screening alone. Methods: In this multicenter study, proven BRCA2 mutation carriers, who developed breast cancer during screening using both digital mammography and state-of-art breast MRI, were identified. Clinical data were reviewed to classify cases in screen-detected and interval cancers. Imaging was reviewed to assess the diagnostic value of mammography and MRI, using the Breast Imaging and Data System (BI-RADS) classification allocated at the time of diagnosis. Results: From January 2003 till March 2019, 62 invasive breast cancers and 23 ductal carcinomas in situ were diagnosed in 83 BRCA2 mutation carriers under surveillance. Overall screening sensitivity was 95.2% (81/85). Four interval cancers occurred (4.7% (4/85)). MRI detected 73 of 85 breast cancers (sensitivity 85.8%) and 42 mammography (sensitivity 49.9%) (p < 0.001). Eight mammography-only lesions occurred. In 1 of 17 women younger than 40 years, a 6-mm grade 3 DCIS, retrospectively visible on MRI, was detected with mammography only in a 38-year-old woman. The other 7 mammography-only breast cancers were diagnosed in women aged 50 years and older, increasing sensitivity in this subgroup from 79.5% (35/44) to 95.5% (42/44) (p ≤ 0.001). Conclusions: In BRCA2 mutation carriers younger than 40 years, the benefit of mammographic screening over MRI was very small. In carriers of 50 years and older, mammographic screening contributed significantly. Hence, we propose to postpone mammographic screening in BRCA2 mutation carriers to at least age 40
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