Drawing a materials map with an autoencoder for lithium ionic conductors.

Efforts to optimize known materials and enhance their performance are ongoing, driven by the advancements resulting from the discovery of novel functional materials. Traditionally, the search for and optimization of functional materials has relied on the experience and intuition of specialized researchers. However, materials informatics (MI), which integrates materials data and machine learning, has frequently been used to realize systematic and efficient materials exploration without depending on manual tasks. Nonetheless, the discovery of new materials using MI remains challenging. In this study, we propose a method for the discovery of materials outside the scope of existing databases by combining MI with the experience and intuition of researchers. Specifically, we designed a two-dimensional map that plots known materials data based on their composition and structure, facilitating researchers' intuitive search for new materials. The materials map was implemented using an autoencoder-based neural network. We focused on the conductivity of 708 lithium oxide materials and considered the correlation with migration energy (ME), an index of lithium-ion conductivity. The distribution of existing data reflected in the materials map can contribute to the development of new lithium-ion conductive materials by enhancing the experience and intuition of material researchers.

Relationship of quantitative flow ratio after second-generation drug-eluting stent implantation to clinical outcomes.

The correlation of fractional flow reserve, which is presently the gold standard for evaluating myocardial ischemia, with three-dimensional quantitative coronary analysis-based quantitative flow ratio (QFR) is well-known. This study aims to evaluate the relationship of QFR after second-generation drug-eluting stent (2nd gen-DES) implantation to clinical outcomes. A total of 61 consecutive lesions, on which 2nd gen-DES implantation was performed from October 2014 to December 2015, were analyzed. Contrast-flow QFR (c-QFR) was obtained using reliable software (QAngio XA 3D) by modeled hyperemic flow velocity derived from coronary angiography without pharmacologically induced hyperemia. Clinical and angiographic data at the follow-up (18-30 months) were obtained from all cases. c-QFR measurement was possible in 52 (85%) lesions. Of these, clinically-driven target vessel revascularization (TVR) was performed in 8 (15%) lesions. Vessel c-QFR was significantly lower in the TVR group (0.703 ± 0.163 vs. 0.883 ± 0.103, p = 0.016). In the results of the receiver operating characteristics analysis for TVR, area under the curve for vessel c-QFR was 0.857. The cutoff point for the prediction of TVR was defined as vessel c-QFR of ≤ 0.82, the sensitivity of 88%, and specificity of 80%. Conclusion: Vessel c-QFR can predict TVR after 2nd gen-DES implantation. Further investigation is warranted to evaluate whether c-QFR guided coronary intervention ameliorates TVR rate.

Variable Selection for Nonparametric Learning with Power Series Kernels.

In this letter, we propose a variable selection method for general nonparametric kernel-based estimation. The proposed method consists of two-stage estimation: (1) construct a consistent estimator of the target function, and (2) approximate the estimator using a few variables by ℓ1-type penalized estimation. We see that the proposed method can be applied to various kernel nonparametric estimation such as kernel ridge regression, kernel-based density, and density-ratio estimation. We prove that the proposed method has the property of variable selection consistency when the power series kernel is used. Here, the power series kernel is a certain class of kernels containing polynomial and exponential kernels. This result is regarded as an extension of the variable selection consistency for the nonnegative garrote (NNG), a special case of the adaptive Lasso, to the kernel-based estimators. Several experiments, including simulation studies and real data applications, show the effectiveness of the proposed method.

Bayesian-Driven First-Principles Calculations for Accelerating Exploration of Fast Ion Conductors for Rechargeable Battery Application.

Safe and robust batteries are urgently requested today for power sources of electric vehicles. Thus, a growing interest has been noted for fabricating those with solid electrolytes. Materials search by density functional theory (DFT) methods offers great promise for finding new solid electrolytes but the evaluation is known to be computationally expensive, particularly on ion migration property. In this work, we proposed a Bayesian-optimization-driven DFT-based approach to efficiently screen for compounds with low ion migration energies ([Formula: see text]. We demonstrated this on 318 tavorite-type Li- and Na-containing compounds. We found that the scheme only requires ~30% of the total DFT-[Formula: see text] evaluations on the average to recover the optimal compound ~90% of the time. Its recovery performance for desired compounds in the tavorite search space is ~2× more than random search (i.e., for [Formula: see text] < 0.3 eV). Our approach offers a promising way for addressing computational bottlenecks in large-scale material screening for fast ionic conductors.

Successful Treatment of Refractory Electrical Storm With Landiolol After More Than 100 Electrical Defibrillations.

Electrical storm (ES) was observed in an 82-year-old man with recent myocardial infarction. Conventional therapy, including amiodarone, could not suppress the ES. After more than 100 electrical defibrillations, we were finally able to control the ES with the administration of landiolol. It is known that landiolol can inhibit ES. However, we hesitate to use landiolol in patients with low cardiac output. We would like to emphasize that careful use of landiolol should be considered in patients with refractory ES after myocardial infarction, although cardiac output is severely reduced.

First molecular identification of Entamoeba polecki in a piglet in Japan and implications for aggravation of ileitis by coinfection with Lawsonia intracellularis.

Parasitic Entamoeba spp. are found in many vertebrate species including humans, as well as many livestock including pigs. In pigs, three Entamoeba spp., E. suis, and E. polecki and E. histolytica as zoonotic species, have been identified, but their pathogenicity has not been fully characterized. Here, we report the bacteriological, virological, and histopathological examination of three piglets with chronic diarrhea. Two animals appeared to be additionally infected with Lawsonia intracellularis, which caused a characteristic proliferative ileitis. In the piglet infected with Entamoeba spp., the trophozoites (approximately 10-15 µm with one nucleus in their cytoplasm) invaded into the lamina propria and the disease was worsened by the formation of ulcers and pseudomembranes. Genetic analysis identified the parasite as E. polecki (99.5% identity). Although E. polecki in humans or animals might be less pathogenic in the case of a single infection, coinfections with other pathogens including L. intracellularis may increase the severity of the disease.

Long QT syndrome associated with adrenal insufficiency in a patient with isolated adrenocorticotropic hormone deficiency.

QT prolongation and Torsades de Pointes were observed in a 44-year-old woman who had adrenal insufficiency caused by isolated adrenocorticotropic hormone deficiency. Although she had several risk factors for QT prolongation, we concluded that the adrenal insufficiency contributed to the QT prolongation, because the electrocardiographic changes were improved after steroid replacement therapy. It is known that the QT interval in a patient with adrenal insufficiency tends to be extended. However, reports on adrenal insufficiency in which the QT interval was sufficiently prolonged to cause Torsades de Pointes are rare. Clinicians should consider the possibility of adrenal insufficiency in patients with QT prolongation.

Dexmedetomidine and clonidine inhibit ventricular tachyarrhythmias in a rabbit model of acquired long QT syndrome.

BACKGROUND: Agents with α-2 adrenoreceptor (AR) agonistic action have reportedly suppressed tachyarrhythmias. METHODS AND RESULTS: We hypothesized that α-2 AR agonists would have an inhibitory effect on abnormal repolarization-related ventricular tachyarrhythmias (VTs). To test this hypothesis, the effects of 2 clinically available α-2 AR agonists (dexmedetomidine and clonidine) on the occurrence of VTs were assessed in a methoxamine-sensitized rabbit model of acquired long QT syndrome (Study 1: n=45). In control rabbits, administration of methoxamine and nifekalant almost invariably caused VTs (14/15). In contrast, incidence of VT significantly decreased during the treatment with dexmedetomidine (1µg·kg(-1)·min(-1): 5/12 [P<0.01 vs. control]) or with clonidine (33.3µg·kg(-1)·min(-1): 10/18 [P<0.01]). To verify that VTs in this animal model are triggered by early afterdepolarization (EAD), the monophasic action potential on the left ventricular surface was recorded in 28 open-chest rabbits (Study 2). EAD-like hump was less frequently detected during treatment with clonidine or dexmedetomidine (2/14) than in saline-treated rabbits (9/10, P<0.005). Presence of a hump was significantly related to the advent of VTs (P<0.05). CONCLUSIONS: Agents with α-2 AR agonistic action have an inhibitory effect on VTs in a rabbit model of long QT syndrome. Alpha-2 AR agonists, especially dexmedetomidine, may be a therapeutic choice for abnormal repolarization-related VTs that are resistant to conventional treatment.