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Imaging modalities for percutaneous coronary intervention (PCI), such as intravascular ultrasound (IVUS) or optical coherence tomography (OCT), have increased in the current PCI era. However, their clinical benefits in acute myocardial infarction (AMI) have not been fully elucidated. This study investigated the long-term outcomes of image-guided PCI in patients with AMI using data from the Korean Acute Myocardial Infarction Registry. A total of 9,271 patients with AMI, who underwent PCI with second-generation drug-eluting stents between November 2011 and December 2015, were retrospectively examined, and target lesion failure (TLF) at 3 years (defined as the composite of cardiac death, target vessel myocardial infarction, and ischemia-driven target lesion revascularization) was evaluated. From the registry, 2,134 patients (23.0%) underwent image-guided PCI (IVUS-guided: n = 1,919 [20.6%]; OCT-guided: n = 215 patients [2.3%]). Based on propensity score matching, image-guided PCI was associated with a significant reduction in TLF (hazard ratio: 0.76; 95% confidence interval: 0.59–0.98, p = 0.035). In addition, the TLF incidence in the OCT-guided PCI group was comparable to that in the IVUS-guided PCI group (5.3% vs 4.7%, p = 0.903). Image-guided PCI, including IVUS and OCT, is associated with favorable clinical outcomes in patients with AMI at 3 years post-intervention. Additionally, OCT-guided PCI is not inferior to IVUS-guided PCI in patients with AMI. [ABSTRACT FROM AUTHOR]

In this study, we introduce two ortho‐carboranyl compounds, namely ICzCB and mTPCB, which exhibit different planarity in their appended π‐conjugated aromatic groups, to investigate the influence of geometric effects on the regulation of the radiative efficiency. Both the compounds are fully characterized, revealing distinct geometric differences (planarity) in their single‐crystal structures. While ICzCB presents strong ICT‐based emission in the solid (film) state, mTPCB displays dual emission in the high‐ and low‐energy regions that originates from locally excited (LE)‐ and ICT‐based processes, respectively. Quantitative analysis of the photophysical characteristics of the compounds shows that the ICT‐based radiative efficiency in ICzCB is higher than that in mTPCB. Consequently, these findings demonstrate that the planarity of the π‐conjugated aryl group appended on o‐carborane, which is represented by planar ICzCB and distorted mTPCB, is an important key to control the ICT‐based radiative decay efficiency. [ABSTRACT FROM AUTHOR]

Background: Anticoagulant therapy has been important for stroke prevention in patients with atrial fibrillation (AF). However, it was not recommended due to its relatively higher risk of bleeding than its lower risk of stroke in patients with a CHA2DS2‐VASc score of 0. Hypothesis: This study aimed to evaluate the predictors of stroke in AF patients with very low risk of stroke. Methods: Between 1990 and 2020, 542 patients with non‐valvular AF (NVAF) with a CHA2DS2‐VASc score of 0 followed up for at least 6 months were enrolled. Patients with only being woman as a risk factor were included as a CHA2DS2‐VASc score of 0 in this study. The primary outcome was stroke or systemic embolism. Results: The primary outcome rate was 0.78%/year. In Cox hazard model, age of ≥50 years at diagnosis (hazard ratio [HR] 6.710, 95% confidence interval [CI] 1.811–24.860, p =.004), LVEDD of ≥46 mm (HR 4.513, 95% CI 1.038–19.626, p =.045), and non‐paroxysmal AF (HR 5.575, 95% CI 1.621–19.175, p =.006) were identified as independent predictors of stroke or systemic embolism. Patients with all three independent predictors had a higher risk of stroke or systemic embolism (4.21%/year), whereas those without did not have a stroke or systemic embolism. Conclusion: The annual stroke or systemic embolism rate in NVAF patients with CHA2DS2‐VASc score of 0 was 0.78%/year, and age at AF diagnosis, LVEDD, and non‐paroxysmal AF were independent predictors of stroke or systemic embolism in patients considered to have a very low risk of stroke. [ABSTRACT FROM AUTHOR]

Rowen showed that the 2 by 2 full matrix rings over strongly π-regular rings need not be strongly π-regular. In this note we extend Rowen's method to the n by n full matrix rings. Moreover we show that the n by n full matrix rings over π-regular rings need not be π-regular. [ABSTRACT FROM AUTHOR]

We first study the quasi-Baerness of R[x; σ, δ] over a quasi-Baer ring R when σ is an automorphism of R, obtaining an affirmative result. We next show that if R is a right principally quasi-Baer ring and σ is an automorphism of R with σ(e) = e for any left semicentral idempotent e ∈ R, then R[x; σ, δ] is right principally quasi-Baer. As a corollary, we have that R[x; δ] over a right principally quasi-Baer ring R is right principally quasi-Baer. Finally, we give conditions under which the quasi-Baernesses (right principal quasi-Baernesses) of R and R[x; σ, δ] are equivalent. [ABSTRACT FROM AUTHOR]

In this note we continue to study zero divisors in power series rings and polynomial rings over general noncommutative rings. We first construct Armendariz rings which are not power-serieswise Armendariz, and find various properties of (power-serieswise) Armendariz rings. We show that for a semiprime power-serieswise Armendariz (so reduced) ring R with a.c.c. on annihilator ideals, R [[ x ]] (the power series ring with an indeterminate x over R ) has finitely many minimal prime ideals, say B 1 ,..., B m , such that B 1 ... B m = 0 and B i = A i [[ x ]] for some minimal prime ideal A i of R for all i , where A 1 ,..., A m are all minimal prime ideals of R . We also prove that the power-serieswise Armendarizness is preserved by the polynomial ring extension as the Armendarizness, and construct various types of (power-serieswise) Armendariz rings. [ABSTRACT FROM AUTHOR]

In this note we study the properties of Amitsur's example for Wedderburn radicals, introducing the concept of W n -reduced rings. The theories of commutative ring and reduced ring are generalized to W n -reduced rings. We characterize the W n -reduced property and study properties of W n -reduced rings. It is shown that the classes of semi-commutative rings, W n -reduced rings, and 2-primal rings are in a strictly increasing order. We extend the class of W n -reduced rings, observing various kinds of extensions containing classical quotient rings, polynomial rings, and power series rings. Communicated by M. Ferrero. [ABSTRACT FROM AUTHOR]

Introduction: The diagnosis of myocardial infarction (MI) needs to be swift and accurate, but definitively diagnosing it based on the first test encountered in clinical practice, the electrocardiogram (ECG), is not an easy task. The purpose of the study was to develop a deep learning (DL) algorithm using multitask learning method to differentiate patients experiencing MI from those without coronary artery disease using image-based ECG data. Methods: A DL model was developed based on 11,227 ECG images. We developed a new ECG interpretation algorithm through signal-guided multitask learning, building on a previously published single-task algorithm. The utility of this model was evaluated by testing 51 physicians in interpreting ECGs with and without the assistance of the DL model. Results: The proposed model demonstrated superior performance, achieving 90.56% accuracy, 83.82% sensitivity, 93.02% specificity, 81.44% precision, and an F1 score of 82.61% in discriminating MI ECG. Overall, the median accuracy of ECG interpretation improved from 62% to 68% with the DL algorithm. Trainees and specialists in internal medicine experienced significant accuracy increases (60–66% for trainees, 72–80% for specialists). In the MI group, NSTEMI accuracy was notably lower than STEMI (33% vs. 80%, p < 0.001), but the DL algorithm improved interpretative capabilities in both NSTEMI and STEMI. Conclusions: Signal-guided multitask DL algorithm demonstrated superior performance compared with previous single-task algorithm. The DL algorithm supports the physicians’ decision discriminating MI ECGs from non-MI ECGs. The improvement was consistent in subgroups of STEMI and NSTEMI. [ABSTRACT FROM AUTHOR]

McCoy proved in 1957 [12] that if a polynomial annihilates an ideal of polynomials over any ring then the ideal has a nonzero annihilator in the base ring. We first elaborate this McCoy's famous theorem further, expanding the inductive construction in the proof given by McCoy. From the proof we can naturally find nonzero c, with f(x)c = 0, in the ideal of R generated by the coefficients of g(x), when f(x), g(x) are nonzero polynomials over a commutative ring R with f(x)g(x) = 0; from which we also obtain a kind of criterion for given a polynomial to be a zero divisor. Based on these results we extend the McCoy's theorem to noncommutative rings, introducing the concept of strong right McCoyness. The strong McCoyness is shown to have a place between the reversibleness (right duoness) and the McCoyness. We introduce a simple way to construct a right McCoy ring but not strongly right McCoy, from given any (strongly) right McCoy ring. If given a ring is reversible or right duo, then the polynomial ring over it is proved to be strongly right McCoy. It is shown that the (strong) right McCoyness can go up to classical right quotient rings. [ABSTRACT FROM AUTHOR]

In this note, a hereditary radical property, called homomorphically reduced rings, is introduced, observed, and applied. The dual concept of this property is also studied with the help of Courter, proving that any ring R (possibly without identity) has an ideal S such that S/K is not homomorphically reduced for each proper ideal K of S; and if L is an ideal of R with L ⊊ S, then L/H is homomorphically reduced for some ideal H of R with H ⊊ L. The concept of the homomorphical reducedness is shown to be equivalent to the left (right) weak regularity and the (strong) regularity for one-sided duo rings. It is proved that homomorphically reduced rings have several useful properties similar to those of (weakly) regular rings. It is proved that the homomorphical reducedness can go up to classical quotient rings. It is shown that if R is a reduced right Ore ring with the ascending chain condition (ACC) for annihilator ideals, then the maximal right quotient ring of R is strongly regular (hence homomorphically reduced). [ABSTRACT FROM AUTHOR]

In this study, we introduce six ortho -carboranyl compounds derived from 9,9-dimethyl-9 H -fluorene 1CH-6CP, each possessing substituents with varying electron-donating capabilities. Their geometric features were comprehensively characterised through single X-ray crystallography. In rigid states (solutions at 77 K, films, aggregates, and crystals), these compounds exhibited intense intramolecular charge-transfer (ICT)-based emissions in the bluish-green spectrum. Notably, the emission quantum efficiency and radiative constant in the crystalline state were proportional to their electronic features, particularly the molecular dipole moment. Furthermore, theoretical modeling of the ground (S 0 ) and first excited (S 1 ) state-optimised structures indicated a gradual enhancement in the orbital occupation at each lowest unoccupied molecular orbital (LUMO) level, correlating with an increase in dipole moment. These findings strongly suggest that the ICT-based radiative efficiency in π-conjugated o -carborane is significantly influenced by the electron-donating properties of the substituents attached to the o -carborane.