475 research outputs found
Neutrino masses in the Lepton Number Violating MSSM
We consider the most general supersymmetric model with minimal particle
content and an additional discrete Z_3 symmetry (instead of R-parity), which
allows lepton number violating terms and results in non-zero Majorana neutrino
masses. We investigate whether the currently measured values for lepton masses
and mixing can be reproduced. We set up a framework in which Lagrangian
parameters can be initialised without recourse to assumptions concerning
trilinear or bilinear superpotential terms, CP-conservation or
intergenerational mixing and analyse in detail the one loop corrections to the
neutrino masses. We present scenarios in which the experimental data are
reproduced and show the effect varying lepton number violating couplings has on
the predicted atmospheric and solar mass^2 differences. We find that with
bilinear lepton number violating couplings in the superpotential of the order 1
MeV the atmospheric mass scale can be reproduced. Certain trilinear
superpotential couplings, usually, of the order of the electron Yukawa coupling
can give rise to either atmospheric or solar mass scales and bilinear
supersymmetry breaking terms of the order 0.1 GeV^2 can set the solar mass
scale. Further details of our calculation, Lagrangian, Feynman rules and
relevant generic loop diagrams, are presented in three Appendices.Comment: 48 pages, 7 figures, v2 references added, typos corrected, published
versio
Telling Tales in School: Storytelling for Self-Reflection and Pedagogical Improvement in Clinical Legal Education
Analytical approach to the quantum-phase transition in the one-dimensional spinless Holstein model
We study the one-dimensional Holstein model of spinless fermions interacting
with dispersion-less phonons by using a recently developed projector-based
renormalization method (PRM). At half-filling the system shows a
metal-insulator transition to a Peierls distorted state at a critical
electron-phonon coupling where both phases are described within the same
theoretical framework. The transition is accompanied by a phonon softening at
the Brillouin zone boundary and a gap in the electronic spectrum. For different
filling, the phonon softening appears away from the Brillouin zone boundary and
thus reflects a different type of broken symmetry state.Comment: 8 pages, 4 figures included; v2: completely revised and extended; v3:
minor changes, final version, to be published in Eur. Phys. J.
Myth and Magic in Early Byzantine Marriage Jewelry: The Persistence of Pre-Christian Traditions
Acceleration, streamlines and potential flows in general relativity: analytical and numerical results
Analytical and numerical solutions for the integral curves of the velocity
field (streamlines) of a steady-state flow of an ideal fluid with
equation of state are presented. The streamlines associated with an accelerate
black hole and a rigid sphere are studied in some detail, as well as, the
velocity fields of a black hole and a rigid sphere in an external dipolar field
(constant acceleration field). In the latter case the dipole field is produced
by an axially symmetric halo or shell of matter. For each case the fluid
density is studied using contour lines. We found that the presence of
acceleration is detected by these contour lines. As far as we know this is the
first time that the integral curves of the velocity field for accelerate
objects and related spacetimes are studied in general relativity.Comment: RevTex, 14 pages, 7 eps figs, CQG to appea
Virtual 3D tumor marking-exact intraoperative coordinate mapping improve post-operative radiotherapy
The quality of the interdisciplinary interface in oncological treatment between surgery, pathology and radiotherapy is mainly dependent on reliable anatomical three-dimensional (3D) allocation of specimen and their context sensitive interpretation which defines further treatment protocols. Computer-assisted preoperative planning (CAPP) allows for outlining macroscopical tumor size and margins. A new technique facilitates the 3D virtual marking and mapping of frozen sections and resection margins or important surgical intraoperative information. These data could be stored in DICOM format (Digital Imaging and Communication in Medicine) in terms of augmented reality and transferred to communicate patient's specific tumor information (invasion to vessels and nerves, non-resectable tumor) to oncologists, radiotherapists and pathologists
British Society of Gastroenterology guidelines for the management of hepatocellular carcinoma in adults
\ua9 Author(s) (or their employer(s)) 2024. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.Deaths from the majority of cancers are falling globally, but the incidence and mortality from hepatocellular carcinoma (HCC) is increasing in the United Kingdom and in other Western countries. HCC is a highly fatal cancer, often diagnosed late, with an incidence to mortality ratio that approaches 1. Despite there being a number of treatment options, including those associated with good medium to long-term survival, 5-year survival from HCC in the UK remains below 20%. Sex, ethnicity and deprivation are important demographics for the incidence of, and/or survival from, HCC. These clinical practice guidelines will provide evidence-based advice for the assessment and management of patients with HCC. The clinical and scientific data underpinning the recommendations we make are summarised in detail. Much of the content will have broad relevance, but the treatment algorithms are based on therapies that are available in the UK and have regulatory approval for use in the National Health Service
Opening up FAIR in-situ land-use reference data: current gaps, obstacles and future challenges
It is becoming increasingly obvious that in order to address current global challenges and achieve the SDGs in the land-use sector, monitoring and evaluation using remote sensing technologies are essential. In particular, with the Copernicus program of the European Union, unprecedented free and open Earth observation data are becoming available. However, in order to improve our remotely sensed based machine learning models, training data in the form of in-situ or annotated land-use or land cover data which are based on the visual interpretation of aerial photographs or very high resolution satellite data are of utmost importance. Without sufficient training data, many land-use and land cover maps lack sufficient quality.
The presentation will provide an overview of existing and open in-situ data in the field of land-use science. It will highlight what land-use data are currently available including data collected though crowdsourcing and the Geo-Wiki toolbox. In particular, it will provide insights into current gaps in land cover, land-use, livestock, forest as well as crop type information globally. It will draw on existing global data products such as those from the Copernicus global land monitoring service, and more recently generated products such as WorldCover and WorldCereal. Furthermore, tools to close those data gaps will be shown. The presentation will furthermore explore current obstacles and limitations to data sharing and debunk current arguments that are often put forth for not sharing in-situ data. These arguments include limited resources, quality issues, competition, as well as time constraints, etc. Specific attention will be given to the role of doners and funders in more clearly defining open and FAIR requirements for in-situ data. The presentation will close by making the audience aware of the LUCKINet consortium, which is trying to make more reference data openly accessible and to build a consistent global land-use change dataset as well as work done on in-situ data within the EU LAMASUS and OEMC project
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