Hubbard-model description of the high-energy spin-spectral-weight distribution in La(2)CuO(4)

The spectral-weight distribution in recent neutron scattering experiments on the parent compound La$_2$CuO$_4$ (LCO), which are limited in energy range to about 450\,meV, is studied in the framework of the Hubbard model on the square lattice with effective nearest-neighbor transfer integral $t$ and on-site repulsion $U$. Our study combines a number of numerical and theoretical approaches, including, in addition to standard treatments, density matrix renormalization group calculations for Hubbard cylinders and a suitable spinon approach for the spin excitations. Our results confirm that the $U/8t$ magnitude suitable to LCO corresponds to intermediate $U$ values smaller than the bandwidth $8t$, which we estimate to be $8t \approx 2.36$ eV for $U/8t\approx 0.76$. This confirms the unsuitability of the conventional linear spin-wave theory. Our theoretical studies provide evidence for the occurrence of ground-state d-wave spinon pairing in the half-filled Hubbard model on the square lattice. This pairing applies only to the rotated-electron spin degrees of freedom, but it could play a role in a possible electron d-wave pairing formation upon hole doping. We find that the higher-energy spin spectral weight extends to about 566 meV and is located at and near the momentum $[\pi,\pi]$. The continuum weight energy-integrated intensity vanishes or is extremely small at momentum $[\pi,0]$. This behavior of this intensity is consistent with that of the spin waves observed in recent high-energy neutron scattering experiments, which are damped at the momentum $[\pi,0]$. We suggest that future LCO neutron scattering experiments scan the energies between 450 meV and 566 meV and momenta around $[\pi,\pi]$.Comment: 23 pages, 5 figure

A trusted infrastructure for symbolic analysis of event-driven web applications

We introduce a trusted infrastructure for the symbolic analysis of modern event-driven Web applica-tions. This infrastructure consists of reference implementations of the DOM Core Level 1, DOM UIEvents, JavaScript Promises and the JavaScriptasync/awaitAPIs, all underpinned by a simpleCore Event Semantics which is sufficiently expressive to describe the event models underlying theseAPIs. Our reference implementations are trustworthy in that three follow the appropriate standardsline-by-line and all are thoroughly tested against the official test-suites, passing all the applicabletests. Using the Core Event Semantics and the reference implementations, we develop JaVerT.Click,a symbolic execution tool for JavaScript that, for the first time, supports reasoning about JavaScriptprograms that use multiple event-related APIs. We demonstrate the viability of JaVerT.Click byproving both the presence and absence of bugs in real-world JavaScript code

Foramen of Winslow hernia: case report of a minimally invasive approach

Foramen of Winslow hernias account for 8% of all internal hernias. Their non-specific presentation and often late diagnosis are associated with an estimated mortality of 50%. The use of complementary diagnostic methods facilitates the diagnosis and planning of the therapeutic strategy. Urgent surgery is the appropriate treatment due to the risk of intestinal ischemia, being laparotomy the main form of approach described. Few cases of laparoscopy are referred to in the literature.info:eu-repo/semantics/publishedVersio

Integrated versus non-integrated perspectives of auditors concerning the new ISO 9001 revision

The process of integration of management systems is being unfolded by a great deal of companies nowadays. A crucial feature of it relates with the audit function and the integrated perceptions of the auditors. This issue is of utmost importance if one takes into account the remarkable effort developed by ISO in the last revisions (2015) of the ISO 9001 and ISO 14001 standards aiming at the standards integration by adopting a common high level structure, identical core context, and common terms and common definitions. The available drafts of the new ISO 45001 standard suggest the same effort. This paper aims, within a global research study on ISO 9001:2015, to report the integrated versus non-integrated perspectives of auditors concerning the new ISO 9001 revision based on the results from a survey conducted among IRCA auditors. It is intended specifically to assess if the perceptions from the auditors holding several certifications are different of those from the auditors that hold solely the QMS certification. Results suggest that the auditors holding several certifications foreseen more benefits from this new revision, i.e., auditors with a wider integrated perspective rate systematically higher the different dimensions assessed in this survey.The authors would like to thank to all the responding auditors for their great collaboration and will pursue this study by applying more powerful statistical tools and adding a time perspective by replicating the survey in the future. This study had the financial support of FCT-Fundacao para a Ciencia e Tecnologia of Portugal under the project UID/CEC/00319/2013. Pedro Domingues is supported by FCT Post-Doc Grant Reference SFRH/BPD/103322/2014.info:eu-repo/semantics/publishedVersio