54 research outputs found
Higher-order topological superconductivity from repulsive interactions in kagome and honeycomb systems
We discuss a pairing mechanism in interacting two-dimensional multipartite lattices that intrinsically leads to a second order topological superconducting state with a spatially modulated gap. When the chemical potential is close to Dirac points, oppositely moving electrons on the Fermi surface undergo an interference phenomenon in which the Berry phase converts a repulsive electronâelectron interaction into an effective attraction. The topology of the superconducting phase manifests as gapped edge modes in the quasiparticle spectrum and Majorana Kramers pairs at the corners. We present symmetry arguments which constrain the possible form of the electronâelectron interactions in these systems and classify the possible superconducting phases which result. Exact diagonalization of the Bogoliubov-de Gennes Hamiltonian confirms the existence of gapped edge states and Majorana corner states, which strongly depend on the spatial structure of the gap. Possible applications to vanadium-based superconducting kagome metals AV3Sb5 (A = K, Rb, Cs) are discussed
The Grizzly, January 29, 2015
Search for New President Continues âą Thefts Reported in New Hall âą Tuition Set for 3.5% Raise in 2015-2016 âą Feick Leaves Ursinus âą Affection is Different in All Cultures âą Peer Advocates Raise Awareness âą New Berman Exhibits Open âą Docent Program Relaunches âą Opinion: Students Should be Cautious When Studying Abroad; After All, You Only Live Once, Right? âą Winter Track Seasons are Well Underway âą Finding Their Balancehttps://digitalcommons.ursinus.edu/grizzlynews/1921/thumbnail.jp
SOLUBILIZATION OF POTASSIUM FROM ALTERNATIVE ROCKS BY HUMIC AND CITRIC ACIDS AND COFFEE HUSK
Pathological chemotherapy response score is prognostic in tubo-ovarian high-grade serous carcinoma: A systematic review and meta-analysis of individual patient data
There is a need to develop and validate biomarkers for treatment response and survival in tubo-ovarian high-grade serous carcinoma (HGSC). The chemotherapy response score (CRS) stratifies patients into complete/near-complete (CRS3), partial (CRS2), and no/minimal (CRS1) response after neoadjuvant chemotherapy (NACT). Our aim was to review current evidence to determine whether the CRS is prognostic in women with tubo-ovarian HGSC treated with NACT.This article is freely available via Open Access. Click on the Publisher URL to access the full-text via the publisher's site
COVID-19 symptoms at hospital admission vary with age and sex: results from the ISARIC prospective multinational observational study
Background:
The ISARIC prospective multinational observational study is the largest cohort of hospitalized patients with COVID-19. We present relationships of age, sex, and nationality to presenting symptoms.
Methods:
International, prospective observational study of 60â109 hospitalized symptomatic patients with laboratory-confirmed COVID-19 recruited from 43 countries between 30 January and 3 August 2020. Logistic regression was performed to evaluate relationships of age and sex to published COVID-19 case definitions and the most commonly reported symptoms.
Results:
âTypicalâ symptoms of fever (69%), cough (68%) and shortness of breath (66%) were the most commonly reported. 92% of patients experienced at least one of these. Prevalence of typical symptoms was greatest in 30- to 60-year-olds (respectively 80, 79, 69%; at least one 95%). They were reported less frequently in children (â€â18 years: 69, 48, 23; 85%), older adults (â„â70 years: 61, 62, 65; 90%), and women (66, 66, 64; 90%; vs. men 71, 70, 67; 93%, each Pâ<â0.001). The most common atypical presentations under 60 years of age were nausea and vomiting and abdominal pain, and over 60 years was confusion. Regression models showed significant differences in symptoms with sex, age and country.
Interpretation:
This international collaboration has allowed us to report reliable symptom data from the largest cohort of patients admitted to hospital with COVID-19. Adults over 60 and children admitted to hospital with COVID-19 are less likely to present with typical symptoms. Nausea and vomiting are common atypical presentations under 30 years. Confusion is a frequent atypical presentation of COVID-19 in adults over 60 years. Women are less likely to experience typical symptoms than men
Intrinsic first- and higher-order topological superconductivity in a doped topological insulator
We explore higher order topological superconductivity in an artificial Dirac
material with intrinsic spin-orbit coupling, which is a doped
topological insulator in the normal state. A mechanism for superconductivity
due to repulsive interactions -- --
has recently been shown to naturally result in higher-order topology in Dirac
systems past a minimum chemical potential \cite{Li2021}. Here we apply this
theory through microscopic modeling of a superlattice potential imposed on an
inversion symmetric hole-doped semiconductor heterostructure, known as
hole-based semiconductor artificial graphene, and extend previous work to
include the effects of spin-orbit coupling. We find that spin-orbit coupling
enhances interaction effects, providing an experimental handle to increase the
efficiency of the superconducting mechanism. We show that the phase diagram of
these systems, as a function of chemical potential and interaction strength,
contains three superconducting states -- a first-order topological
state, a second-order topological spatially modulated state, and a
second-order topological extended -wave state, . We calculate the
symmetry-based indicators for the and states, which prove
these states possess second-order topology. Exact diagonalisation results are
presented which illustrate the interplay between the boundary physics and spin
orbit interaction. We argue that this class of systems offer an experimental
platform to engineer and explore first and higher-order topological
superconducting states
483 Delayed Gastric Emptying Is Common in Liver Cirrhosis and Is Associated With Reduced Appetite and Glucose Absorption: A Risk Factor for Malnutrition?
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