Generalized q-Onsager Algebras and Dynamical K-matrices

A procedure to construct $K$-matrices from the generalized $q$-Onsager algebra \cO_{q}(\hat{g}) is proposed. This procedure extends the intertwiner techniques used to obtain scalar (c-number) solutions of the reflection equation to dynamical (non-c-number) solutions. It shows the relation between soliton non-preserving reflection equations or twisted reflection equations and the generalized $q$-Onsager algebras. These dynamical $K$-matrices are important to quantum integrable models with extra degrees of freedom located at the boundaries: for instance, in the quantum affine Toda field theories on the half-line they yield the boundary amplitudes. As examples, the cases of \cO_{q}(a^{(2)}_{2}) and \cO_{q}(a^{(1)}_{2}) are treated in details

Central extension of the reflection equations and an analog of Miki's formula

Two different types of centrally extended quantum reflection algebras are introduced. Realizations in terms of the elements of the central extension of the Yang-Baxter algebra are exhibited. A coaction map is identified. For the special case of $U_q(\hat{sl_2})$, a realization in terms of elements satisfying the Zamolodchikov-Faddeev algebra - a `boundary' analog of Miki's formula - is also proposed, providing a free field realization of $O_q(\hat{sl_2})$ (q-Onsager) currents.Comment: 11 pages; two references added; to appear in J. Phys.

Relationship Between Arterial Access and Outcomes in ST-Elevation Myocardial Infarction With a Pharmacoinvasive Versus Primary Percutaneous Coronary Intervention Strategy: Insights From the STrategic Reperfusion Early After Myocardial Infarction (STREAM) Study.

BACKGROUND: The effectiveness of radial access (RA) in ST-elevation myocardial infarction (STEMI) has been predominantly established in primary percutaneous coronary intervention (pPCI) with limited exploration of this issue in the early postfibrinolytic patient. The purpose of this study was to compare the effectiveness and safety of RA versus femoral (FA) access in STEMI undergoing either a pharmacoinvasive (PI) strategy or pPCI. METHODS AND RESULTS: Within STrategic Reperfusion Early After Myocardial Infarction (STREAM), we evaluated the relationship between arterial access site and primary outcome (30-day composite of death, shock, congestive heart failure, or reinfarction) and major bleeding according to the treatment strategy received. A total of 1820 STEMI patients were included: 895 PI (49.2%; rescue PCI [n=379; 42.3%], scheduled PCI [n=516; 57.7%]) and 925 pPCI (50.8%). Irrespective of treatment strategy, there was comparable utilization of either access site (FA: PI 53.4% and pPCI 57.6%). FA STEMI patients were younger, had lower presenting systolic blood pressure, lesser Thrombolysis In Myocardial Infarction risk, and more ∑ST-elevation at baseline. The primary composite endpoint occurred in 8.9% RA versus 15.7% FA patients (P<0.001). On multivariable analysis, this benefit on the primary composite outcome favoring RA persisted (adjusted odds ratio [OR], 0.59; 95% CI, 0.44-0.78; P<0.001) and was evident in both pPCI (adjusted OR, 0.63; 95% CI, 0.43-0.92) and PI cohorts (adjusted OR, 0.57 95% CI, 0.37-0.86; P interaction=0.730). There was no difference in nonintracranial major bleeding with either access group (RA vs FA, 5.2% vs 6.0%; P=0.489). CONCLUSIONS: Regardless of the application of a PI or pPCI strategy, RA was associated with improved clinical outcomes, supporting current STEMI evidence in favor of RA in PCI. CLINICAL TRIAL REGISTRATION: URL: https://www.clinicaltrials.gov/. Unique identifier: NCT00623623