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This study explores the food transport efficiency (E) in a termite tunnel consisting of a main tunnel and a 2-segment loop tunnel through a model simulation. Simulated termites navigate between the main and loop tunnels through branching nodes (a , b , c , d) with associated probabilities (P 1, P 2, P 3, P 4). The loop tunnel locations (δ) are considered: near the nest (δ  = 1), at the center of the main tunnel (δ  = 2), and close to the food site (δ  = 3). The results reveal that for δ  = 1, paths such as a → d → b → c and c → d → b → a exhibited high E values. Conversely, for δ  = 2, P 3 and P 4 demonstrate elevated E values ranging from 0.4 to 0.6. For δ  = 3, paths like c → d or c → b display high E values, emphasizing the significance of in-loop separation tunnels (characterized by P 3 and P 4) in alleviating traffic congestion. Partial rank correlation validates that P 1 and P 2 minimally influence E , while P 3 and P 4 significantly negatively impact E , regardless of δ. However, for δ  = 2, the influence of P 3 and P 4 is notably reduced due to the positional symmetry of the loop tunnel. In the discussion, we address model limitations and propose strategies to overcome them. Additionally, we outline potential experimental validations to ensure a comprehensive understanding of the dynamics governing termite food transport within tunnels. [ABSTRACT FROM AUTHOR]

Herein, we report a photocatalytic method for the synthesis of 2‐quinolones under mild conditions by employing α‐diazo acetamide as substrates. The use of Eosin Y as a photocatalyst allows an economical and environmentally benign synthetic method. The process involves the generation of radicals from diazo compounds promoted by a visible‐light‐induced proton‐coupled electron transfer (PCET) mechanism. The method demonstrates a broad substrate scope to provide various aryl‐ and alkyl‐substituted 2‐quinolones. To support the proposed mechanism, a series of mechanistic experiments were conducted. [ABSTRACT FROM AUTHOR]

The development of low-cost, catalytically efficient, and durable earth-abundant electrocatalysts for replacing platinum-group-metal (PGM) materials has always been at the forefront of materials engineering for sustainable hydrogen generation. Metal–organic frameworks (MOFs), especially cobalt (Co)-based zeolitic imidazolate framework (ZIF-67) can be used as precursors or templates for preparing non-precious electrocatalysts. Herein, we successfully fabricated metallic cobalt/cobalt sulfide hetero-nanostructures embedded within N-doped graphitic carbon nanocages (Co/CoxSy@NC-750) by the one-step pyrolysis of ZIF-67 under H2 and S. Co/CoxSy@NC-750 exhibits a hollow configuration with a high degree of morphological uniformity. The pyrolysis temperature and resulting control of the composition played a crucial role in material engineering with application-oriented properties. Examination of the activity for the hydrogen evolution reaction (HER) in 0.5 M H2SO4 and 1.0 M KOH aqueous electrolytes demonstrated that Co/CoxSy@NC-750 exhibits substantially improved HER performance in both acidic (overpotential of 130 mV and Tafel slope of 82 mV dec−1) and basic (330 mV and 160 mV dec−1) media. The unique metallic cobalt core/cobalt sulfide shell is particularly beneficial for maintaining the electrochemical long-term durability (≥30 h and 40 h in acids and bases, respectively). This study provides guidance for achieving MOF-derived inorganic nanomaterials with the desired structural heterogeneity and compositional control for non-PGM electrochemical catalysis through fundamental quantification of the structural and catalytic parameters. [ABSTRACT FROM AUTHOR]

For single‐atom‐layer hydrogen evolution reaction catalysts, enrichment of the 1T‐phase in monolayer molybdenum disulfide is important to achieve ideal metal utilization efficiency and exposure of active surface atoms. Herein, it is discovered that the 1T‐phase degree in monolayer MoS2 can be enhanced through sulfidation of the Pd species deposited on MoS2 (PdxSy/1T‐MoS2). Raman and X‐ray photoelectron spectroscopy reveal that the sulfidation‐assisted phase transition results in considerably greater proportions of 1T‐phase fraction (up to 86%) without using alkali‐metal‐based approaches. Observations of S‐atom displacement/translation at the atomic level contribute to the understanding of the phase transformation of MoS2. The maximized surface atom activation and metal utilization efficiency in PdxSy/1T‐MoS2 lead to unprecedentedly high mass activity (−3444 A mgPd−1) and turnover frequency (1892 s−1), three orders of magnitude higher than those of commercial Pt/C 10 wt% (3.6 A mgPt−1 and 3.6 s−1). The sulfidation‐assisted 1T‐phase enrichment has major implications for the designs of efficient electrocatalysts through MoS2 phase engineering. [ABSTRACT FROM AUTHOR]

Termites are believed to have evolved in a way that optimizes their foraging efficiency, which involves both searching for food and transporting it efficiently. Although the search efficiency has been well-studied through tunnel pattern analysis, transport efficiency has received limited attention due to the challenges of directly observing behavior that is highly influenced by environmental conditions. In this study, we introduce an individual-based model to simulate transport behavior and examine transport efficiency (E) by considering the tunnel surface irregularities and curvature, which are critical environmental factors. The model is characterized by four control variables: tunnel curvature (k 1), termite stopping time at irregularity sites (k 2), irregularity distribution (k 3), and irregularity density (k 4). The simulation results indicate that as k 1 increases, E decreases, while k 3 has little impact on E. The impact of k 4 on E is decisive; when k 4 ≤ 6, an increase in k 4 results in increased traffic jam frequency and a faster reduction in E. However, when k 4 > 6, the jamming frequency is not significantly affected, reducing the decrease in E. k 2 strongly contributes to reducing E without significantly affecting the frequency. In the discussion section, we explore potential mechanisms that termites use to maintain transport efficiency in heterogeneous soils, and discuss how to improve the model to better reflect real-termite systems. [ABSTRACT FROM AUTHOR]

Synthesis of heterocycles from 1,2‐diarylalkene derivatives through electrosynthesis under metal‐ and oxidant‐free conditions has been discovered. Cathodic reduction of 2‐alkenylbenzoic acid or anodic oxidation of 2‐alkenylbenzamide, 2‐alkenylphenol and 2‐alkenylaniline leads to the formation of reactive radical intermediates which afford corresponding phthalide, isochroman‐1‐one, isoindolin‐1‐one, benzofuran, and indole in satisfying yields with good functional group tolerance. Interestingly, different chemoselectivities were found in different reaction solvents. Several mechanistic investigations including cyclic voltammetry studies and control experiments were carried out to elucidate the reaction mechanisms. [ABSTRACT FROM AUTHOR]

Metal chalcogenides are promising candidates for various energy storage applications. Herein, a ternary Fe2GeS4 compound was synthesized using a simple solid-state method and applied as versatile electrodes for rechargeable Li/Na–Fe2GeS4 battery cathodes and Li/Na-ion battery anodes. In addition, distinctive Li and Na reaction pathways for Fe2GeS4 consisting of insertion and conversion reactions have been demonstrated. For its application as rechargeable Li/Na–Fe2GeS4 battery cathodes, Li‖Fe2GeS4 and Na‖Fe2GeS4 battery systems were electrochemically evaluated by controlling the cut-off voltages within the insertion reaction and they showed high electrochemical performance with high reversible volumetric capacities and cyclability with appropriate cell potentials (Li‖Fe2GeS4: ∼550 mA h cm−3 over 100 cycles with ∼1.6 V; Na‖Fe2GeS4: ∼555 mA h cm−3 over 100 cycles with ∼1.2 V). In addition, for using Fe2GeS4 as an anode for Li-ion batteries (LIBs) and Na-ion batteries (NIBs), graphene-wrapped Fe2GeS4 nanocomposite (Fe2GeS4-rGO) comprising Fe2GeS4 nanocrystallites (∼10–15 nm) embedded on reduced graphene oxide (rGO) was synthesized through a simple two-step synthetic method to improve the electronic/ionic conductivity, structural stability, and mechanical strain relaxation. The electrochemical test results indicated that the Fe2GeS4-rGO exhibited high initial reversible gravimetric capacities (730 mA h g−1 for LIB, 563 mA h g−1 for NIB), high rate capability (520 mA h g−1 at 3C for LIB, 470 mA h g−1 at 2C for NIB), and an excellent cycling performance at a high 1C rate (capacity retention: ∼100% over 500 cycles for LIBs, ∼93% over 200 cycles for NIBs). Therefore, we believe that Fe2GeS4 is a highly applicable compound material for various battery systems. [ABSTRACT FROM AUTHOR]

Summary: Bismuth has garnered attention as a promising anode material for Na‐ion batteries (NIBs) because of its high volumetric capacity and appropriate operating potential. However, the large and repeated volume variations of the Bi anode during sodiation/desodiation lead to a poor electrochemical performance; thus, a rational design for Bi‐based materials is essential for their application to NIB anodes. First, the Na reaction pathway of Bi was analyzed using various cutting‐edge ex situ analysis tools. Subsequently, two different types of Bi‐based nanocomposite materials were prepared to enhance the Na storage performance of Bi: one is an amorphous carbon (a‐C)‐modified Bi nanocomposite (Bi@a‐C) fabricated via mechanical treatment and the other is a metal–organic framework (MOF)‐derived polyhedral Bi nanocomposite (p‐Bi@C) fabricated via chemical treatment. The Na storage performance of p‐Bi@C is much higher than that of Bi@a‐C because of the homogeneous anchoring effect of Bi nanocrystals in the MOF‐derived polyhedral C matrices, which have robust and high Na‐ion conduction. The p‐Bi@C delivered a highly reversible capacity (302 mAh g−1 over 100 cycles) and high rate capability (205 mAh g−1 at 2C). Therefore, this study provides a rational design of Bi‐based nanocomposite materials for application to high‐performance NIB anodes. [ABSTRACT FROM AUTHOR]

Given a number field L , we define the degree of an algebraic number v ∈ L with respect to a choice of a primitive element of L. We propose the question of computing the minimal degrees of algebraic numbers in L , and examine these values in degree 4 Galois extensions over ℚ and triquadratic number fields. We show that computing minimal degrees of non-rational elements in triquadratic number fields is closely related to solving classical Diophantine problems such as congruent number problem as well as understanding various arithmetic properties of elliptic curves. [ABSTRACT FROM AUTHOR]

The development of high-capacity and high-power lithium-ion batteries (LIBs) is a key challenge to meet the increasing demand for advanced mobile electronics and electric vehicles. A novel high-capacity and high-power Ga2Te3 anode material for LIBs, which exhibits a distinctive reaction mechanism with Li ions, has been introduced in this study. Two types of Ga2Te3/C composite were prepared via different synthetic routes, namely carbon thermal decomposition (TD) and high-energy ball milling (BM), to improve the electrochemical performance of Ga2Te3 anodes, and their electrochemical performances were compared. The electrochemical evaluation results indicate that the Ga2Te3/C composite produced by BM (BM-Ga2Te3/C) showed better electrochemical performance by delivering much smaller Ga2Te3 nanocrystallites than the Ga2Te3/C composite produced by TD (TD-Ga2Te3/C). Furthermore, the BM-Ga2Te3/C anode showed a highly reversible initial volumetric capacity (1245 mA h cm−3), stable capacity retention (93.2% after 500 cycles), and excellent high-rate performance (∼1000 mA h cm−3 at 1C after 500 cycles). These high electrochemical performances, which were demonstrated via ex situ analyses, were attained by a unique three-step nano-confinement process of Ga2Te3 in BM-Ga2Te3/C. Thus, this study provides a new material development strategy of employing mechano- and electro-chemical nano-confinement processes to develop high-performance anodes for LIBs. [ABSTRACT FROM AUTHOR]

The most common screening techniques to diagnose a patient's illness are blood collection and intravenous procedures. To find a collection or injection site, conventional blood collection support tools, such as latex tubing and buckle-type tourniquets, are generally used to compress the patient's blood vessels. This conventional passive method has significant problems such as latex allergy, vulnerability to site contamination and potential bloodstream infection, and physical damage due to improper use. To overcome the disadvantages of conventional blood collection support tools, an automatic tourniquet with a high-elasticity biocompatible strap was constructed. The automatic tourniquet is designed to automatically adjust the strap length using a motor to control the pressure according to the body dimensions of patients. In order to evaluate the performance of the automatic tourniquet, blood flow characteristics were analyzed using an ultrasound measurement system. The results demonstrated that the automatic tourniquet showed better performance compared with those of other blood collection support tools. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) materials present various extraordinary properties that are advantageous in optoelectronic devices with atomically thin nature. Despite their excellent light–matter interaction, a low optical absorption that is proportional to thickness is considered to be a major limitation. In this study, a gap-mode plasmon structure is applied to the Schottky junction of Au–MoS2 to compensate for its low absorption. The magnitude of the gap-mode plasmon is generally known to be inversely proportional to the gap distance between two metal nanostructures; hence, an atomically thin 2D material can be considered to be a good candidate for a gap spacer. Owing to the gap-mode plasmon structure, the photoresponsivity of the proposed device is enhanced by approximately 11.6 times from 25 to 290 A W−1 under 1 nW of laser power, without photoresponse time degradation. Two operation modes, named the photovoltaic and the photoconductive mode, are also observed through different response times; these present different carrier transport mechanisms depending on the existence of bias voltage. [ABSTRACT FROM AUTHOR]

Site-selective modification of oligonucleotides serves as an indispensable tool in many fields of research including research of fundamental biological processes, biotechnology, and nanotechnology. Here we report chemo- and regioselective modification of oligonucleotides based on rhodium(I)-carbene catalysis in a programmable fashion. Extensive screening identifies a rhodium(I)-catalyst that displays robust chemoselectivity toward base-unpaired guanosines in single and double-strand oligonucleotides with structurally complex secondary structures. Moreover, high regioselectivity among multiple guanosines in a substrate is achieved by introducing guanosine-bulge loops in a duplex. This approach allows the introduction of multiple unique functional handles in an iterative fashion, the utility of which is exemplified in DNA-protein cross-linking in cell lysates. The methods for investigation of DNA-binding proteins require site-selective chemical modifications to be introduced into oligonucleotides. Here, the authors report a chemo- and regioselective method for the modification of unpaired guanosines in single- and double-stranded oligonucleotides, based on Rh(I)-carbene catalysis. [ABSTRACT FROM AUTHOR]

Herein, a Na quasi‐intercalation concept in black P is developed in order to achieve superior P‐based Na‐ion battery (NIB) anodes. Firstly, black P with a puckered layer structure is synthesized via a simple solid‐state reaction using commercially available red P. Additionally, an amorphous carbon modified black P nanocomposite (black P@C) is prepared to optimize its electrochemical Na reversibility. Furthermore, the Na reaction pathways of black P are demonstrated using various ex situ analytical tools. During sodiation/desodiation, black P undergoes the two‐step reactions of sequential quasi‐intercalation of NaP formation (at 0.25 V) and conversion of Na3P formation (at 0 V). Interestingly, black P@C shows poor cycling performance when using the conversion reaction, but it shows superior performance when using the quasi‐intercalation reaction between black P and NaP. Therefore, we anticipate that the Na quasi‐intercalation in black P@C will lead to high‐performance NIB anodes. [ABSTRACT FROM AUTHOR]

The capture, sequestration and utilization of carbon dioxide have attracted global attention in the environmental field, science and industry. The concurrent conversion of CO2 and CH4 is a reasonable solution to reduce greenhouse gases, but it remains a challenging research topic. Herein, we reveal the catalytic activity of bifunctional half-sandwich complexes (metal = Ru, Rh, and Ir) in the direct conversion of methane and carbon dioxide to acetic acid (AA) using density functional theory. The use of Ru/Rh/Ir metals with ethanediphosphine (PP), N-tosylethylenediamine (NNTs), and ethylene glycol (OO) ligands shows superb performance in lowering the free energy (ΔG) barrier (ΔG‡) for the conversion. To activate CH4 and CO2 molecules, we used extra additives to reduce the high energy barriers required by simple metal–ligand complexes. For CH4 activation, additives of AA and trifluoroacetic acid (TFA) were used to assist the proton abstraction in the Ru–NNTs/OO complexes, while no acid additives were used for the PP ligands. In the case of the PP ligands, the C–H activation occurs through a "concerted oxidative addition–reductive elimination" (OA–RE) process, whereas in the NNTs/OO ligands, C–H activation occurs through "cyclometallation deprotonation" (CMD) irrespective of the presence of acid additives. The reduction in ΔG‡ for CH4 activation in Ru–NNTs/OO is 5–10 kcal mol−1 using acid additives. In contrast, in Ru–PP, this ΔG‡ barrier is 20 kcal mol−1 without additives. For CO2 activation, AlCl3 (Lewis acid) was used to insert CO2 into the metal site of the Ru–NNTs/OO and Ru/Rh/Ir–PP complexes. The reduction in ΔG‡ using AlCl3 for CO2 activation in Ru–NNTs·AA/OO·2TFA and Ru/Rh/Ir–PP is 15–30 kcal mol−1. Then, the overall activation barrier is reduced to 20–27 kcal mol−1. [ABSTRACT FROM AUTHOR]

Oxidative [3+3] cycloadditions offer an efficient route for six‐membered‐ring formation. This approach has been realized based on an electrochemical oxidative coupling of indoles/enamines with active methylene compounds followed by tandem 6π‐electrocyclization leading to the synthesis of dihydropyrano[4,3‐b]indoles and 2,3‐dihydrofurans. The radical–radical cross‐coupling of the radical species generated by anodic oxidation combined with the cathodic generation of the base from O2 allows for mild reaction conditions for the synthesis of structurally complex heterocycles. [ABSTRACT FROM AUTHOR]

Oxidative [3+3] cycloadditions offer an efficient route for six‐membered‐ring formation. This approach has been realized based on an electrochemical oxidative coupling of indoles/enamines with active methylene compounds followed by tandem 6π‐electrocyclization leading to the synthesis of dihydropyrano[4,3‐b]indoles and 2,3‐dihydrofurans. The radical–radical cross‐coupling of the radical species generated by anodic oxidation combined with the cathodic generation of the base from O2 allows for mild reaction conditions for the synthesis of structurally complex heterocycles. [ABSTRACT FROM AUTHOR]

UV-activated alkyne–alkene [2 + 2] cycloaddition has served as an important tool to access cyclobutenes. Although broadly adopted, the limitations with UV light as an energy source prompted us to explore an alternative method. Here we report alkyne–alkene [2 + 2] cycloaddition based on visible light photocatalysis allowing the synthesis of diverse cyclobutenes and 1,3-dienes via inter- and intramolecular reactions. Extensive mechanistic studies suggest that the localized spin densities at sp2 carbons of alkenes account for the productive sensitization of alkenes despite their similar triplet levels of alkenes and alkynes. Moreover, the efficient formation of 1,3-dienes via tandem triplet activation of the resulting cyclobutenes is observed when intramolecular enyne cycloaddition is performed, which may serve as a complementary means to the Ru(II)-catalyzed enyne metathesis. In addition, the utility of the [2 + 2] cycloaddition has been demonstrated by several synthetic transformations including synthesis of various extended π-systems. [2 + 2] cycloaddition of alkynes with alkenes would normally require UV light irradiation. Here, the authors report an alkyne–alkene [2 + 2] cycloaddition based on visible light energy transfer photocatalysis, both inter- and intramolecularly, to afford cyclobutenes and 1,3-dienes. [ABSTRACT FROM AUTHOR]

Sphingosine kinase1 (SphK1) is an acetyl-CoA dependent acetyltransferase which acts on cyclooxygenase2 (COX2) in neurons in a model of Alzheimer's disease (AD). However, the mechanism underlying this activity was unexplored. Here we show that N-acetyl sphingosine (N-AS) is first generated by acetyl-CoA and sphingosine through SphK1. N-AS then acetylates serine 565 (S565) of COX2, and the N-AS-acetylated COX2 induces the production of specialized pro-resolving mediators (SPMs). In a mouse model of AD, microglia show a reduction in N-AS generation, leading to decreased acetyl-S565 COX2 and SPM production. Treatment with N-AS increases acetylated COX2 and N-AS-triggered SPMs in microglia of AD mice, leading to resolution of neuroinflammation, an increase in microglial phagocytosis, and improved memory. Taken together, these results identify a role of N-AS in the dysfunction of microglia in AD. Neuronal sphingosine kinase 1 (SphK1) acetylates COX2 which is needed for microglial phagocytosis activity, and release of pro-resolving mediators (SPMs) from neurons. Here the authors examine how SphK1-mediates COX2 acetylation, and how this leads to increased secretion of SPMs from neurons in the context of Alzheimer's disease models. [ABSTRACT FROM AUTHOR]

To design a high‐performance Fe2O3‐based anode for Li‐ion batteries (LIBs), Fe2O3 nanocubes (Fe2O3–NCs) and their graphite‐modified (Fe2O3–NCs–G) composite were synthesized using a simple two‐step method. The Fe2O3–NCs–G composite consisted of homogeneously distributed individual Fe2O3–NCs with graphite matrices, which were confirmed by X‐ray diffraction (XRD) and scanning electron microscopy. In addition, the Fe2O3–NCs–G composite delivered a high specific surface area and good electrical conductivity. To demonstrate the electrochemical Li insertion/extraction mechanism of the Fe2O3–NCs–G composite electrodes, ex‐situ XRD and Fe K‐edge extended X‐ray absorption fine structure analyses were performed. Because of its structural merits, the synthesized Fe2O3–NCs–G composite exhibited high electrochemical performance featuring a high reversible capacity of 865 mAh g−1 after 100 cycles and a fast rate capability, thus demonstrating its high possibility for high‐performance LIBs. [ABSTRACT FROM AUTHOR]

Objectives: Second shot arterial phase (SSAP) imaging is an additional arterial phase image obtained by re-injecting a small amount of contrast medium after routine dynamic imaging in gadoxetic acid-enhanced liver MRI. We aimed to evaluate the feasibility and additional value of a SSAP image in gadoxetic acid-enhanced liver MRI.Methods: One hundred seventy-two patients who underwent SSAP imaging after re-injection of 4 mL of contrast material after routine dynamic imaging (original) in gadoxetic acid-enhanced liver MRIs were included. Motion artifacts on arterial phase (AP) images were rated using a 5-point scale and were compared between the original AP images and SSAP images. We evaluated visual detection rates of arterial hypervascularity on the original AP and SSAP images and their subtraction images in patients with hypervascular hepatocellular carcinoma (HCC).Results: The motion artifact of the SSAP images was significantly lower than that of the original AP images (mean score, 1.76 vs 2.06; p < 0.001). In particular, motion artifacts reduced significantly in the SSAP images of patients with substantial motion artifacts in their original AP images (2.28 vs 3.28; p < 0.001). Among the 30 HCC lesions showing hypervascularity on original AP images, only four (4/30, 13.3%) appeared hyperintense on SSAP images. However, subtraction images of SSAP clearly demonstrated arterial hypervascularity in all HCCs.Conclusion: SSAP images showed significantly fewer motion artifacts than the original AP images. Subtraction images of SSAP maintained the detectability of arterial hypervascularity, although SSAP images showed poor visual detection of arterial hypervascularity of HCC.Key Points: • Arterial phase images obtained after a second injection of a small amount of contrast medium (second shot arterial phase [SSAP]) improved motion artifacts compared to the original AP images. • The motion artifacts improved significantly in the SSAP images of patients with substantial motion artifacts in their original AP images. • Subtraction images of SSAP demonstrated the arterial hypervascularity characteristic of HCC at a level comparable to that of the original AP image. [ABSTRACT FROM AUTHOR]

The development of recycling technology for waste glass is crucial because numerous types of waste glass are generated daily. To recycle waste glass, we developed a facile conversion technology for turning waste glass into high-capacity Li storage materials. Nanostructured Si-based composites were synthesized by a simple solid-state synthesis method using three waste glass types: soda-lime, borosilicate, and quartz. Firstly, various waste glass types were mechanically crushed into powders, after which they were reduced into Si using a Mg reducing agent powder by a simple high-energy ball-milling (BM) process, forming composites comprising Si and MgO (Si/MgO). The potentials of these composites for use as Li-ion battery (LIB) anodes were investigated. To further enhance the electrochemical performances of the Si/MgO composites, amorphous C-modified composites (Si/MgO/C) were simply prepared by further high-energy BM processing for 0.5 h. The Si/MgO/C composites comprised well-dispersed nanocrystalline Si, Li-inactive MgO, and various Li-inactive oxides from the additives used for glass formation within the buffering amorphous C matrices. The Si/MgO/C composites prepared by the facile recycling of waste borosilicate and quartz glasses exhibited high reversible capacities of 487 and 549 mA h g−1 and stable capacity retentions of approximately 100% and 93% after 200 cycles, respectively. [ABSTRACT FROM AUTHOR]

A layered germanium telluride (GeTe) and its C-modified nanocomposite (GeTe–C) are synthesized by a simple solid-state synthesis technique, and their electrochemical behaviors for rechargeable lithium-ion batteries (LIBs) are evaluated. Various ex situ analytical tools are employed to demonstrate the electrochemical Li-insertion/-extraction mechanisms of the electrodes. GeTe during Li-insertion exhibits two-step conversion/alloying reactions, and does not recombine after Li-extraction. Interestingly, although GeTe–C shows the same two-step conversion/alloying reactions during Li-insertion, Ge and Te fully recombine after Li-extraction. Owing to the full recombination reactions by the ongoing Li-cycling, GeTe–C shows excellent electrochemical Li-ion storage performances, such as highly reversible capacities (1st Li-insertion/-extraction capacity: 841/691 mA h g−1 or 1767/1450 mA h cm−3), extremely rigid cycling durability (capacity retention: 97.8% after 100 cycling), and rapid rate-capabilities (940 mA h cm−3 at 3C-rate). Therefore, the GeTe–C modified with layered GeTe and amorphous C is a promising anode material with a high energy density for high-performance LIBs. [ABSTRACT FROM AUTHOR]

Antimony selenide and its carbon composite were synthesized through a mechanochemical process and investigated as anode materials for sodium-ion secondary batteries. X-ray diffraction (XRD) with rietveld refinement and transmission electron microscopy (TEM) analyses confirm that Sb2Se3 were composed of agglomerated highly crystalline nanocrystallites and the Sb2Se3/C composite consisted of nanocrystalline Sb2Se3 dispersed homogeneously throughout an amorphized carbon matrix. The initial Coulombic efficiency, rate capability, and cycle performance of the Sb2Se3/C composite were superior to those of Sb, or Sb2Se3. The Sb2Se3/C composite, in particular, showed excellent cycle stability, with 98.2% of initial capacity at 200 mA g−1 after 200 cycles. Based on the reaction potentials, ex situ XRD patterns and ex situ HR-TEM analysis of the Sb2Se3/C composite electrode revealed the structural changes which occurred reversibly within the Sb2Se3/C composite by conversion and recombination reaction during sodiation and desodiation process. Furthermore, XPS analysis study was carried out for identifying the surface films formed on both the electrodes and their effects on the performances.Graphical abstract: [ABSTRACT FROM AUTHOR]

Abstract: Synthesis of highly substituted quinolines has been developed based on three‐component radical cascade based on visible‐light photoredox catalysis. This tandem coupling reaction has been coordinated to proceed with high chemoselectivity based on the differential electronic properties of coupling partners. Subjection of electron‐rich β‐aminoacrylates with electron‐deficient halides and alkenes to the optimized conditions leads to the formation of quinolines in good yields after in situ oxidation of tetrahydroquinolines. Detailed mechanistic studies which reveal an unexpected reaction pathway is described. [ABSTRACT FROM AUTHOR]

This Feature Article introduces the preparation and synthetic utility of α-diazo oxime ethers. α-Oximino carbenes are useful synthons for N-heterocycles, and can be easily prepared from α-diazo oxime ethers as precursors. We begin with the preparation of α-diazo oxime ethers and their application in [3+2] cycloaddition. It turns out that the nature of metals bound to carbenes plays a crucial role in modulating the reactivity of α-oximino carbenes, in which copper carbenes smoothly react with enamines, whereas the less reactive enol ethers and nitriles require gold carbenes. In Section 3.2, a discussion on N–O and C–H bond activation is presented. Carbenes derived from diazo oxime ethers show unique reactivity towards N–O and C–H bond activation, in which the proximity of the two functionalities, carbene and oxime ether, dictates the preferred reaction pathways toward pyridines, pyrroles, and 2H-azirines. In Section 3.3, the development of tandem reactions based on α-diazo oxime ethers is discussed. The nature of carbenes in which whether free carbenes or metal complexes are involved dissects the pathway and forms different types of 2H-azirines. The 2H-azirine formation turned out to be an excellent platform for the tandem synthesis of N-heterocycles including pyrroles and pyridines. In the last section, we describe the electrophilic activation of 2H-azirines with vinyl carbenes and oximino carbenes. The resulting azirinium species undergo rapid ring expansion rearrangements to form pyridines and pyrazines. [ABSTRACT FROM AUTHOR]

Purpose: To identify the most reliable imaging features for differentiating hepatocellular carcinoma with paradoxical uptake on the hepatobiliary phase (HCCpara ) from focal nodular hyperplasia (FNH)-like nodules using Gd-EOB-DTPA-enhanced MRI.Materials and Methods: This was a retrospective study. Twenty patients with HCCpara and 21 patients with FNH-like nodules were included. The following MRI features were evaluated using 3.0 Tesla unit by two radiologists: signal intensity (SI) on T1-, T2-, and diffusion-weighted imaging (DWI), arterial enhancement pattern, washout appearance on the portal venous phase (PVP) and/or transitional phase (TP), uptake pattern on the hepatobiliary phase (HBP), "T2 scar," "EOB scar," and chemical shift on in- and out-of-phase images. Multivariate logistic regression analysis was performed to assess MRI features for prediction of HCCpara .Results: Compared with FNH-like nodules, HCCpara had significantly more frequent heterogeneous T1 SI (P < 0.0001), T2 hyperintensity (P = 0.032), heterogeneous arterial enhancement (P < 0.0001), washout appearance on the PVP and/or TP (P < 0.0001), heterogeneous uptake on the HBP (P < 0.0001), absence of "EOB scar" (P < 0.0001), and hyperintensity on DWI (P = 0.004). Multivariate logistic regression analysis revealed washout appearance as the only independent imaging feature associated with HCCpara (odds ratio, 7.019; P = 0.042). Washout appearance also showed the best diagnostic performance with a sensitivity of 90% and a specificity of 100%.Conclusion: Washout appearance on the PVP and/or TP is the most reliable imaging feature for differentiating HCCpara from FNH-like nodules.Level Of Evidence: 3 J. MAGN. RESON. IMAGING 2017;45:1599-1608. [ABSTRACT FROM AUTHOR]

Puckered-layer-structured germanium monosulfide (GeS) and corresponding amorphous-carbon-decorated nanocomposites (GeS–C) were synthesized and used to fabricate Li-ion battery anodes which displayed remarkable reversible capacity above 1050 mA h g−1 after 100 cycles. [ABSTRACT FROM AUTHOR]

An efficient synthetic method for carbazoles has been developed employing diazo anilinoalkynes as substrates. Sequential activation of the orthogonal functional groups embedded in diazo anilinoalkyne substrates by tandem gold–copper catalysis leads to the formation of highly substituted carbazoles. Substrate scope reveals a broad tolerability toward the substitution on aryl groups. [ABSTRACT FROM AUTHOR]

2H to 1T transformation, monolayer molybdenum disulfide, palladium sulfide, phase-dependent HER activity, sulfidation-induced 1T enrichment Keywords: 2H to 1T transformation; monolayer molybdenum disulfide; palladium sulfide; phase-dependent HER activity; sulfidation-induced 1T enrichment EN 2H to 1T transformation monolayer molybdenum disulfide palladium sulfide phase-dependent HER activity sulfidation-induced 1T enrichment 1 1 1 06/20/23 20230616 NES 230616 B Hydrogen Evolution Reaction b In article number 2300183, Cheol-Min Park, Ki-Joon Jeon, and co-workers discover the sulfidation of Pd-based nanoclusters on monolayer MoS SB 2 sb as a two-birds-with-one-stone strategy for tuning the metallic 1T-MoS SB 2 sb phase and promoting the hydrogen production of a heterogeneous catalyst. Pd Sulfidation-Induced 1T-Phase Tuning in Monolayer MoS2 for Hydrogen Evolution Reaction (Adv. [Extracted from the article]

Here, we report, for the first time, the preparation of Sb2Te3 and the Sb2Te3/C nanocomposite by a simple solid-state synthetic route and their application as Li-ion battery anode materials. The nanocomposite showed an interesting reaction mechanism and outstanding electrochemical performance. [ABSTRACT FROM AUTHOR]

Cationic gold complexes of α-oximimino carbenes have been identified to react with weak nucleophiles including enol ethers and nitriles. These findings allowed us to develop the highly efficient synthesis of pyrroles and oxazoles. [ABSTRACT FROM AUTHOR]

Objectives: To compare the diffusion parameters of intravoxel incoherent motion (IVIM) diffusion-weighted imaging (DWI) between the "reflux" and the "non-reflux" kidneys, and to evaluate the feasibility of using IVIM DWI to predict vesicoureteral reflux (VUR) in children with a urinary tract infection (UTI).Methods: Eighty-three kidneys from 57 pediatric patients with a UTI were classified into "reflux" and "non-reflux" groups according to voiding cystourethrography (VCUG) results. The apparent diffusion coefficient (ADC), true diffusion coefficient (D), pseudo-diffusion coefficient (D*), and perfusion fraction (PF) were measured and compared in the renal pelvis of both groups. Four indices (D*/ADC, PF/ADC, D*/D, and PF/D) were calculated and receiver operating characteristic (ROC) curve analyses were performed.Results: VURs were detected on VCUG in 21 kidneys. PF and D* were significantly higher in the "reflux" group than in the "non-reflux" group. The indices were all significantly higher. The PF/D index showed the best diagnostic performance in predicting VUR in children with UTI (Az = 0.864).Conclusion: PF and D* were significantly higher in the "reflux" kidney than in the "non-reflux" kidney. Our new index (PF/D) could prove useful for predicting VUR.Key Points: • IVIM DWI is both radiation-free and contrast media-free. • IVIM DWI index is easily calculated by combining diffusion parameters. • IVIM DWI may help predict VUR in children with UTI. • PF is significantly higher in the "reflux" than the "non-reflux" kidneys. • A new VUR index, PF/D could prove useful for predicting VUR. [ABSTRACT FROM AUTHOR]

To investigate the electrochemical reaction mechanism of As, which shows poor electrochemical reversibility with Li, an As/C nanocomposite was prepared using a straightforward high-energy mechanical milling technique. The electrochemical reaction mechanism of the As/C nanocomposite electrode with Li was elucidated by ex situ XRD and HRTEM analyses in combination with differential capacity plot analysis. Electrochemical tests showed that the As/C nanocomposite exhibited good reversibility between the LiAs (0.85 V) and As (2 V) phases showing quasi-intercalation reaction. [ABSTRACT FROM AUTHOR]

Energy cost of transmitting a single bit of information is approximately the same as that needed for processing a thousand operations in a typical sensor node. Thus, a practical way to prolong a wireless sensor network lifetime is to reduce the sensor energy consumption in data transmissions. Data aggregation is an efficient way to minimize energy consumption on sensors. In this paper, we propose a practical secure data aggregation scheme, Sen-SDA , based on an additive homomorphic encryption scheme, an identity-based signature scheme, and a batch verification technique with an algorithm for filtering injected false data. We then investigate the feasibility of our scheme using low-cost microcontrollers choosing two popular IEEE 802.15.4-compliant wireless sensor network hardware platforms, MICAz and Tmote Sky, used in real-life deployments. [ABSTRACT FROM AUTHOR]

We exploited the unstable characteristics of solid SnO at all temperatures to develop a simple, fast, inexpensive, and scalable method based on high-energy ball milling to transform SnO into a disproportionated nanocomposite that consists of amorphized Sn and nanocrystalline SnO2. In the first step of this process, nanostructured disproportionated SnO (d-SnO) made up of nanosized Sn and SnO2 crystallites is produced by ball milling pure SnO powder. The electrochemical performance of the d-SnO is then enhanced by creating a d-SnO/C nanocomposite through additional ball milling. This d-SnO/C nanocomposite was analyzed by various techniques, such as XRD, high-resolution transmission electron microscopy, and extended X-ray absorption fine structure analysis, and consists of amorphized Sn (≈sub-3 nm) and nanocrystalline SnO2 (≈5-15 nm) within an amorphous carbon matrix. This structure produces excellent electrochemical performances with a high initial energy density (first charge: 892 mA h g−1 or 1436 mA h cm−3), a relatively good initial Coulombic efficiency (≈73 %), long cycling stability (above 642 mA h g−1 or 1034 mA h cm−3 over 300 cycles), and a fast rate capability (3 C: 585 mA h g−1 or 942 mA h cm−3). Based on these results, we believe that d-SnO/C nanocomposite electrodes have the potential to create a new area of research in the field of high-performance Li-alloy-based anode materials. [ABSTRACT FROM AUTHOR]

Zinc telluride (ZnTe) and a nanostructured ZnTe/C composite were prepared by a simple solid-state synthetic route, and their potential as electrode materials for rechargeable Li-ion batteries was investigated. The electrochemical conversion/partial recombination reactions between ZnTe and Li were determined using ex situ X-ray diffraction and extended X-ray absorption fine structure analysis. X-ray diffraction and high-resolution transmission electron microscopy confirmed that the ZnTe/C nanocomposite consisted of ZnTe nanocrystallites that were uniformly distributed within an amorphous carbon matrix. The nanostructured ZnTe/C composite electrode exhibited excellent electrochemical properties with a high capacity (1st charge: 530 mA h g−1), cycling durability (over 200 cycles), and fast rate capability (1 C: ca. 550 mA h g−1, 3 C: ca. 504 mA h g−1). [ABSTRACT FROM AUTHOR]

Purpose To compare intravoxel incoherent motion diffusion weight imaging IVIM-DWI MRI with DMSA for the evaluation of cortical defect in pediatric upper urinary tract infection (UTI) patients. Materials and Methods Forty-three kidneys of 22 pediatric patients with the first episode of febrile upper UTI were evaluated. DWI using IVIM model was performed with eight b factors. The presence of cortical defect was evaluated on apparent diffusion coefficient (ADC) map. DMSA was used as the standard of reference. ADC, true diffusion coefficient (D), pseudo-diffusion coefficient (D*), and perfusion fraction (F) in both defect and nondefect area were calculated and compared. Results Cortical defects were detected in 14 kidneys by IVIM-DWI. The sensitivity, specificity, positive predictive value, and negative predictive value of IVIM-DWI MRI for the detection of defects was 93.3%, 100%, 100%, and 96.5%, respectively. Mean values of ADC, D, D*, and F were 1.12 ± 0.15, 1.05 ± 0.10, 33 ± 17 (× 10−3 mm2/s), and 0.14 ± 0.09 in the defect foci. In normal foci, ADC, D, D*, and F were 1.37 ± 0.09, 1.31 ± 0.10, 43 ± 19 (× 10−3 mm2/s), and 0.12 ± 0.04, respectively. ADC and D were significantly lower in defect group than nondefect group ( P < 0.01). Conclusion IVIM-DWI can allow both direct visualization and quantitative measurement of cortical defects. J. Magn. Reson. Imaging 2014;40:545-551. © 2013 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]