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The cell cycle is driven by cyclin‐dependent kinases (Cdks). The decision whether the cell cycle proceeds is made during G1 phase, when Cdk4/6 functions. Cyclin‐dependent kinase inhibitor 2 (Cdkn2) is a specific inhibitor of Cdk4/6, and their interaction depends on D84 in Cdkn2 and R24/31 in Cdk4/6. This knowledge is based mainly on studies in mammalian cells. Here, we comprehensively analyzed Cdk4/6 and Cdkn2 in invertebrates and found that Cdk4/6 was present in most of the investigated phyla, but the distribution of Cdkn2 was rather uneven among and within the phyla. The positive charge of R24/R31 in Cdk4/6 was conserved in all analyzed species in phyla with Cdkn2. The presence of Cdkn2 and the conservation of the positive charge were statistically correlated. We also found that Cdkn2 has been tightly linked to Fas associated factor 1 (Faf1) during evolution. We discuss potential interactions between Cdkn2 and Cdk4/6 in evolution and the possible cause of the strong conservation of the microsynteny. [ABSTRACT FROM AUTHOR]

We have developed a phenomenological turbulent model with one-dimensional (1D) simulation based on Reynolds decomposition. Using this method, we have systematically studied models with different effects of compression, mixing length parameters, and diffusion coefficient of internal energy, turbulence energy, and electron fraction. With employed turbulent effects, supernova explosion can be achieved in 1D geometry, which can mimic the evolution of shock in the 3D simulations. We found that enhancement of turbulent energy by compression affects the early shock evolution. The diffusion coefficients of internal energy and turbulent energy also affect the explodability. The smaller diffusion makes the shock revival faster. Our comparison between the two reveals that the diffusion coefficients of internal energy has a greater impact. These simulations would help understand the role of turbulence in core-collapse supernovae. [ABSTRACT FROM AUTHOR]

The synthesis and phase-transition behavior of a novel homologous series of 4′-alkylseleno-4-cyanobiphenyls [nSeCB, where n represents the number of carbon atoms in the alkyl chains (n = 1–8)] is reported. Polarized optical microscopy and differential scanning calorimetry revealed that the nSeCB homologs with n = 1–6 exhibited monotropic nematic (N) phases at low temperatures, which appeared below 10 °C for nSeCB with n = 3–6. However, no liquid crystal (LC) phase was observed in the nSeCB with n = 7 and 8. In addition, we compared the phase-transition behaviors of the nSeCB homologs with those of the alkyl-, alkoxy-, and alkylthio-based homologous series (nCB, nOCB, and nSCB, respectively). The LC phases of certain nCB and nOCB were enantiotropic, whereas those of all nSCB and nSeCB were monotropic. The longer-chain nCB, nOCB, and nSCB homologs formed layered smectic A (SmA) phases, whereas only N phases were observed for the nSeCB homologs within the tested range of the chain lengths. The nSeCB series showed the lowest isotropic-to-N phase-transition (TIN) temperatures for all chain lengths except 1SeCB. The low mesogenic ability and LC phase-transition temperatures of nSeCB were attributed to the higher flexibility, steric bulk, and lower molecular anisotropy due to the C–Se–C bond, which has lower rotational barriers, longer bond lengths, and smaller bond angles than the other bonds compared herein. The varying alkyl-chain lengths had a greater influence on the phase-transition temperatures of the nSeCB homologs than those of the other homologs. Furthermore, the single-crystal structural analysis of 1SeCB was conducted to obtain insights into the phase-transition behaviors. [ABSTRACT FROM AUTHOR]

To design ultrabright fluorescent solid dyes, a crystal engineering strategy that enables monomeric emission by blocking intermolecular electronic interactions is required. We introduced propylene moieties to distyrylbenzene (DSB) as bridges between the phenyl rings either side of its C=C bonds. The bridged DSB derivatives formed compact crystals that emit colors similar to those of the same molecules in dilute solution, with high quantum yields. The introduction of flexible seven‐membered rings to the DSB core produced moderate distortion and steric hindrance in the DSB π‐plane. However, owing to this strategy, it was possible to control the molecular arrangement with almost no decrease in the crystal density, and intermolecular electronic interactions were suppressed. The bridged DSB crystal structure differs from other DSB derivative structures; thus, bridging affords access to novel crystalline systems. This design strategy has important implications in many fields and is more effective than the conventional photofunctional molecular crystal design strategies. [ABSTRACT FROM AUTHOR]

The predictive value of echocardiographic parameters for early worsening heart failure (WHF), worsening of symptoms of heart failure requiring intensification of therapy during an admission for acute decompensated heart failure (ADHF), has not been elucidated. Sixteen centers in Japan prospectively enrolled 303 ADHF hospitalized patients who did not receive positive inotropic agents as an initial therapy. Physical and Doppler echocardiographic examinations were performed before the initial therapy and the association of low output findings and occurrence of early WHF were tested. Early WHF occurred in 63 patients with a median duration of 6 (IQR: 2–23) hours from the administration of the initial therapy. In patients with left ventricular (LV) ejection fraction <40% (N = 153), echocardiographic stroke volume index, and cardiac index showed greater c-index [95% confidence interval, 0.71 (0.61–0.79) and 0.72 (0.63–0.80), respectively] compared to single low perfusion finding (symptomatic hypotension, reduced pulse pressure, and impaired mentation) other than cool extremities. When physical findings were combined (low perfusion score), the predictive ability improved to the similar levels of echocardiographic LV output parameters [c-index: 0.69 (0.60–0.76)]. However, addition of cardiac index significantly improved the prognostic ability when added to low perfusion score [0.82 (0.74–0.87), p < 0.001]. In contrast, in patients with LV ejection fraction ≥40% (N = 150), low perfusion score, rather than LV output parameters, was predictive of early WHF [c-index: 0.73 (0.56–0.85)]. We demonstrated the predictive value of echocardiographic LV output indices for early WHF in ADHF patients with LV systolic dysfunction. These data support the motivation for routine use of echocardiography for initial assessment of ADHF. [Display omitted] • Predictive value of echocardiographic LV output parameters for early WHF was tested. • Echocardiographic CI well predicted early WHF in ADHF HFrEF patients. • Association of echocardiographic CI was independent of clinically relevant parameters in HFrEF. • Data of PREDICT encourages routine use of Doppler echocardiography in ADHF management. [ABSTRACT FROM AUTHOR]

To describe the effects of the alkylthio groups on the phase transition behavior of organic liquid crystal (LC) molecules and their causes, we herein scrutinize the melting points (Tm) and nematic (N)–isotropic phase transition temperatures (TNI or TIN) of alkylthio-, alkoxy-, and alkyl-based LC homologues. To begin with, phase transitions are compared for three homologous series of 4-cyanophenyl benzoates bearing 4-alkyl-, 4-alkoxy-, and 4-alkylthio groups (denoted by nCPB, nOCPB, and nSCPB, respectively) with different alkyl chains (CnH2n+1; n = 1–8). In contrast to nCPB and nOCPB, some of which exhibit enantiotropic N phases, all alkylthio-based nSCPB are found to display monotropic N phases. The nSCPB homologues exhibit higher Tm than not only their corresponding nCPB for all n but also nOCPB counterparts in the case of long chains (n ≥ 6); a similar trend is confirmed also for the Tm values of the structurally similar biphenyl- and cyanobiphenyl-based homologues. Meanwhile, the TNI or TIN values of nSCPB and nCPB are lower than those of nOCPB for all n, and higher for nSCPB than for nCPB with the short chains (n = 1 and 2) but comparable with one another for the longer chains (n ≥ 3). In addition, our discussion addresses more anisotropic 1,4-phenylene bis(benzoate) LCs with alkylthio and alkoxy groups. Furthermore, single-crystal structures of three LC molecules with methylthio groups are examined. Several interatomic contacts around the sulfur atoms such as S⋯HC contacts are indicated, which differ for respective molecules. The present study draws the following conclusions. The alkylthio groups mostly play the role of decreasing the phase transition temperatures (especially TNI or TIN) and hindering LC formation for organic rod-like molecules, primarily due to conformational flexibility, steric bulkiness, and lower molecular anisotropy imposed by C–S–C. The sulfur atom contributes to intermolecular attractive interactions, which are reflected in phase transitions as spatially averaged phenomena (i.e., dispersion force and more polarizable π-systems). The influence of those interactions become more pronounced with lengthening alkyl chains. [ABSTRACT FROM AUTHOR]

Intercalation of Cu into layered polychalcogenide La2O2S2 was demonstrated to be viable both under solvothermal conditions at 200 °C and mechanical ball milling at ambient temperature. This result evidences the soft-chemical nature of metal intercalation into layered polychalcogenides driven by the redox reactivity of anion–anion bonds. [ABSTRACT FROM AUTHOR]

In recent years, all-solid-state batteries (ASSBs) have been attracting attention as the next generation batteries for electric vehicles, energy storage systems, etc. Despite the growing interest, there are still many challenges faced in the commercial use of ASSBs. One of the biggest issues is the internal resistance, especially generated at the interface between solid electrolyte and electrode. The internal resistance at the interface limits the charge-discharge cycling performances. In order to solve this issue, it is necessary to examine the chemical and physical interactions at the interface. In this study, we have performed a detailed characterization of a LiPON/LiCoO2 interface using time-of-flight secondary ion mass spectrometry, x-ray photoelectron spectroscopy, ultraviolet photoelectron spectroscopy, and low-energy inverse photoelectron spectroscopy to obtain information on chemical species, chemical compositions, chemical states, and energy band diagrams. These powerful techniques have revealed that an interlayer between LiPON and LiCoO2 was formed due to the temperature rise during the manufacturing process. The temperature rise caused a change of the LiPON network structure and stimulated Co reduction in the LiCoO2 layer near the interface. Energy band diagram analysis suggests that the electron diffusion from LiPON to LiCoO2 may have triggered the reduction of Co. We concluded that the chemical changes that occur at the interface caused an increase in interfacial impedance. Preventing the chemical reduction of Co would be a key to minimize the internal resistance. In this article, the detailed chemical interactions between the LiPON and LiCoO2 layers will be discussed. [ABSTRACT FROM AUTHOR]

Transition metal dichalcogenides (TMDs) display a rich variety of instabilities such as spin and charge orders, Ising superconductivity, and topological properties. Their physical properties can be controlled by doping in electric double‐layer field‐effect transistors (FET). However, for the case of single layer NbSe2, FET doping is limited to ≈1 × 1014 cm−2, while a somewhat larger charge injection can be obtained via deposition of K atoms. Here, by performing angle‐resolved photoemission spectroscopy, scanning tunneling microscopy, quasiparticle interference measurements, and first‐principles calculations it is shown that a misfit compound formed by sandwiching NbSe2 and LaSe layers behaves as a NbSe2 single layer with a rigid doping of 0.55–0.6 electrons per Nb atom or ≈6 × 1014 cm−2. Due to this huge doping, the 3 × 3 charge density wave is replaced by a 2 × 2 order with very short coherence length. As a tremendous number of different misfit compounds can be obtained by sandwiching TMDs layers with rock salt or other layers, this work paves the way to the exploration of heavily doped 2D TMDs over an unprecedented wide range of doping. [ABSTRACT FROM AUTHOR]

Background: Early worsening heart failure (WHF), defined as worsening of symptoms and signs of heart failure requiring intensification of medical or mechanical therapy during an admission for acute decompensated heart failure (ADHF), has recently been recognized as a risk of morbidity or mortality after the discharge. Although echocardiographic parameters of left ventricular (LV) output has been shown to be associated with long-term outcome in heart failure patients, its predictive value for early WHF has not been elucidated. Methods: Prospect trial to Elucidate the utility of EchocarDiography-based Cardiac output in acute heart failure (PREDICT) is a multicenter, nonrandomized, prospective observational study to test the predictive value of echocardiographic LV output parameters for early WHF in ADHF patients. We will enroll patients admitted to 16 participating hospitals due to ADHF who did not receive positive inotropic agents as an initial therapy. Primary outcome will be set at early WHF defined as need for initiation of positive inotropic agents within 7 days after the admission. Predictive accuracy will be compared between Doppler echocardiographic LV output (stroke distance, stroke volume index, and cardiac index) and low perfusion findings assessed by physical examination. Results: N/A. Conclusions: The PREDICT is expected to provide large data set to test the predictive value of echocardiographic LV output for early WHF in ADHF patients. [ABSTRACT FROM AUTHOR]

We herein report phase transitions, mesomorphism, birefringence behavior and photoluminescence properties of symmetric liquid crystal (LC) dimers based on diphenylacetylene or tolane. A homologous series of 4-methoxy tolanes linked with oligomethylene spacers consisting of carbon numbers (m) of 5–12 via ether linkages (1OTOmOTO1) were developed. The 1OTOmOTO1 series exhibited only a nematic phase, in contrast with the previously reported homologues with long terminal alkoxy chains, which exhibit layered smectic phases. We revealed that even the longest even-numbered 1OTO12OTO1 exhibits higher birefringence (Δn) than the shortest odd-numbered 1OTO5OTO1 at similar shifted temperatures. This fact suggests that the parity effect in the spacer that enhances Δn in an even-m surpasses the dilution effect that decreases Δn in large m for LC dimers. In addition, the photophysical measurements found aggregation-induced emission of the dimer concomitant with the emergence of an abnormally structured fluorescence band, which perhaps arises from a unique excited state enabled by aggregation. Single-crystal structural analysis revealed that diphenylacetylene moieties in neighboring molecules have face-to-edge orthogonal packing with one another, supporting the strong face-to-edge preferences of diphenylacetylene moiety and its enhanced fluorescence in aggregated states. [ABSTRACT FROM AUTHOR]

To broaden the application of aggregation‐induced emission (AIE) luminogens (AIEgens), the design of novel small‐molecular dyes that exhibit high fluorescence quantum yield (Φfl) in the solid state is required. Considering that the mechanism of AIE can be rationalized based on steric avoidance of non‐radiative decay pathways, a series of bridged stilbenes was designed, and their non‐radiative decay pathways were investigated theoretically. Bridged stilbenes with short alkyl chains exhibited a strong fluorescence emission in solution and in the solid state, while bridged stilbenes with long alkyl chains exhibited AIE. Based on this theoretical prediction, we developed the bridged stilbenes BPST[7] and DPB[7], which demonstrate excellent AIE behavior. [ABSTRACT FROM AUTHOR]

Twenty years ago, the concept of aggregation‐induced emission (AIE) was proposed, and this unique luminescent property has attracted scientific interest ever since. However, AIE denominates only the phenomenon, while the details of its underlying guiding principles remain to be elucidated. This minireview discusses the basic principles of AIE based on our previous mechanistic study of the photophysical behavior of 9,10‐bis(N,N‐dialkylamino)anthracene (BDAA) and the corresponding mechanistic analysis by quantum chemical calculations. BDAA comprises an anthracene core and small electron donors, which allows the quantum chemical aspects of AIE to be discussed. The key factor for AIE is the control over the non‐radiative decay (deactivation) pathway, which can be visualized by considering the conical intersection (CI) on a potential energy surface. Controlling the conical intersection (CI) on the potential energy surface enables the separate formation of fluorescent (CI:high) and non‐fluorescent (CI:low) molecules [control of conical intersection accessibility (CCIA)]. The novelty and originality of AIE in the field of photochemistry lies in the creation of functionality by design and in the active control over deactivation pathways. Moreover, we provide a new design strategy for AIE luminogens (AIEgens) and discuss selected examples. [ABSTRACT FROM AUTHOR]

We demonstrate here the low temperature topochemical insertion of transition elements (Fe, Ni, and Cu) in precursors containing pre-formed (Sn)2− (n = 2 and 3) oligomers. Indeed, this soft chemistry route opens the door to the easy, orientated synthesis of low dimensional transition metal compounds provided that the elemental metal can retrocede electron(s) to empty antibonding sulfur σ* levels. [ABSTRACT FROM AUTHOR]

Key Clinical Message: Despite the requirement for histopathological evidence to make a definite diagnosis of cardiac sarcoidosis, the sensitivity of endomyocardial biopsy is still low. Recently, Japanese Circulation Society suggests a new strategy that patients diagnosed clinically do not require the endomyocardial biopsy evidence. Physicians should familiarize themselves with such paradigm shifts. [ABSTRACT FROM AUTHOR]

Key Clinical Message: Although conventional microbiology cultures may be negative, polymerase chain reaction (PCR) can effectively identify both typical and atypical microorganisms. With careful interpretation, PCR could become the gold‐standard diagnostic test for culture‐negative bacterial pericarditis. Although conventional microbiology cultures may be negative, polymerase chain reaction (PCR) can effectively identify both typical and atypical microorganisms. With careful interpretation, PCR could become the gold‐standard diagnostic test for culture‐negative bacterial pericarditis. [ABSTRACT FROM AUTHOR]

Abstract: Layered transition metal compounds represent a major playground to explore unconventional electric or magnetic properties. In that framework, topochemical approaches that mostly preserve the topology of layered reactants have been intensively investigated to tune properties and/or design new materials. Topochemical reactions often involve the insertion or deinsertion of a chemical element accompanied by a change of oxidation state of the cations only. Conversely, cases where anions play the role of redox centers are very scarce. Here we show that the insertion of copper into two dimensional precursors containing chalcogen dimers (Q2)2− (Q=S, Se) can produce layered materials with extended (CuQ) sheets. The reality of this topochemical reaction is demonstrated here for different pristine materials, namely La2O2S2, Ba2F2S2, and LaSe2. Therefore, this work opens up a new synthetic strategy to design layered transition metal compounds from precursors containing polyanionic redox centers. [ABSTRACT FROM AUTHOR]

Background Visual estimation of left ventricular ejection fraction (LVEF) is widely applied to confirm quantitative EF. However, visual assessment is subjective, and variability may be influenced by observer experience. We hypothesized that a learning session might reduce the misclassification rate. Methods Protocol 1: Visual LVEFs for 30 cases were measured by 79 readers from 13 cardiovascular tertiary care centers. Readers were divided into 3 groups by their experience: limited (1–5 years, n = 28), intermediate (6–11 years, n = 26), and highly experienced (12-years, n = 25). Protocol 2: All readers were randomized to assess the effect of a learning session with reference images only or feedback plus reference images. After the session, 20 new cases were shown to all readers following the same methodology. To assess the concordance and accuracy pre- and post-intervention, each visual LVEF measurement was compared to overall average values as a reference. Results Experience affected the concordance in visual EF values among the readers. Groups with intermediate and high experience showed significantly better mean difference (MD), standard deviation (SD), and coefficient of variation (CV) than those with limited experience at baseline. The learning session with reference image reduced the MD, SD, and CV in readers with limited experience. The learning session with reference images plus feedback also reduced proportional bias. Importantly, the misclassification rate for mid-range EF cases was reduced regardless of experience. Conclusion This large multicenter study suggested that a simple learning session with reference images can successfully reduce the misclassification rate for LVEF assessment. [ABSTRACT FROM AUTHOR]

With growing attention to sustainability and recognition of the impact of global warming problems, energy supply and consumption have become critically important. This paper presents the construction of a modeling platform accommodating cooperative energy management systems (EMSs), which virtually produces the model of a smart city with a distribution network (DN) by using a wide range of data obtained from the real world. The platform involves models of various EMSs, governing the operation of a power system or controlling consumer-installed devices, and simulating the power flow, electrical losses, and voltage in the DN. In addition, indices measuring the sustainability of the model city, such as CO2 emission, are estimated from scenarios, for example, photovoltaic system installation, electric vehicle penetration, etc. The results can be visually displayed and the platform is highly versatile and applicable to various types of issues associated with smart cities. Two case studies are presented in detail. [ABSTRACT FROM PUBLISHER]

In hot working of multiphase steels, the thermal history of the material before working affects the phase balance of the steel. The aim of this research is to investigate the influence of the thermal history before hot working on hot workability by performing hot uniaxial tensile tests. Duplex stainless steel was chosen as the experimental material because it has the typical dual-phase structure consisting of δ Ferrite and, Austenite and its phase balance changes with temperature. The phase ratio of δ Ferrite is higher at high temperatures, and the ratio of the relatively Austenite phase increases as the temperature decreases. In addition, part of the δ Ferrite phase transforms to the brittle Sigma phase at 1000°C and lower. The effect of the temperature history before working on hot workability was investigated with two thermal control patterns, cooling (Type I) or heating (Type II) from the holding temperature before hot working. To clarify the effect of the cooling and heating rates before hot working, two greatly different rates (0.1°C/sec, 10.0°C/sec) were used in both cooling (Type I) and heating (Type II). Under the Type I condition, the heating temperature was 1250°C, and the hot working test temperature was in the range of 650-1150°C. With the higher cooling rate, hot workability showed a large increase in the temperature range of 850-1150°C. This phenomenon was caused by retention of a high phase ratio of δ Ferrite at high temperature, together with inhibition of the transformation to the brittle Sigma phase at under 1000°C. Under the Type II condition with the heating temperature of 1050°C, hot workability was the same between different heating rates. On the other hand, when the holding temperature was 950°C, at which the Sigma phase forms, hot workability decreased drastically at hot working temperatures under 1100°C under the high heating rate condition. This phenomenon was caused by the remaining brittle Sigma phase and harder Austenite, which were not completely dissolved and transformed due to the high heating rate. Thus, with multi-phase steels in which the phase balance displays temperature dependence, it is important to select appropriate experimental conditions considering microstructural changes when evaluating hot workability with a combination of rapid cooling or rapid heating before the hot working. [ABSTRACT FROM AUTHOR]