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Imbalanced domain prediction analysis is currently one of the hot research topics. Many real‐world data mining analyses involve using imbalanced data to obtain predictive models. In the context of imbalance, research on classification problems has been extensive, but research on regression problems is negligible. Rare values rarely occur in imbalanced regression problems, but the focus is on accurately predicting the continuous target variables of rare instances. One of the challenges in imbalanced regression is finding a suitable strategy to rebalance the original dataset in order to improve the predictive performance of the model in rare instances. In this study, two algorithms are proposed: sigma nearest over‐sampling based on convex combination for regression (SNOCCR) and affine combination‐based over‐sampling (ACOS). ACOS rebalances the original dataset by generating new instances through the affine combinations of the original examples. The region where the new instances are generated can be adjusted based on the distribution of the data, ensuring that the generated cases better mimic the distribution of the original examples. The comparison among ACOS, SNOCCR, and other preprocessing methods was conducted on 15 datasets to validate the predictive performance of models trained on rebalanced datasets for rare instances. The experimental results indicate that ACOS outperforms other existing methods. In this study, two over‐sampling algorithms are proposed: sigma nearest over‐sampling based on convex combination for regression (SNOCCR) and affine combination‐based over‐sampling (ACOS) in order to improve the predictive performance of the model in imbalanced regression. The experimental results indicate that ACOS outperforms other existing methods. [ABSTRACT FROM AUTHOR]

The development of nonpyrolytic catalysts featuring precisely defined active sites represents an effective strategy for investigating the fundamental relationship between the catalytic activity of oxygen reduction reaction (ORR) catalysts and their local coordination environments. In this study, we have synthesized a series of model electrocatalysts with well‐defined CoN4 centers and nonplanar symmetric coordination structures. These catalysts were prepared by a sequential process involving the chelation of cobalt salts and 1,10‐phenanthroline‐based ligands with various substituent groups (phen(X), where X=OH, CH3, H, Br, Cl) onto covalent triazine frameworks (CTFs). By modulating the electron‐donating or electron‐withdrawing properties of the substituent groups on the phen‐based ligands, the electron density surrounding the CoN4 centers was effectively controlled. Our results demonstrated a direct correlation between the catalytic activity of the CoN4 centers and the electron‐donating ability of the substituent group on the phenanthroline ligands. Notably, the catalyst denoted as BCTF−Co‐phen(OH), featuring the electron‐donating OH group, exhibited the highest ORR catalytic activity. This custom‐crafted catalyst achieved a remarkable half‐wave potential of up to 0.80 V vs. RHE and an impressive turnover frequency (TOF) value of 47.4×10−3 Hz at 0.80 V vs. RHE in an alkaline environment. [ABSTRACT FROM AUTHOR]

The development of nonpyrolytic catalysts featuring precisely defined active sites represents an effective strategy for investigating the fundamental relationship between the catalytic activity of oxygen reduction reaction (ORR) catalysts and their local coordination environments. In this study, we have synthesized a series of model electrocatalysts with well‐defined CoN4 centers and nonplanar symmetric coordination structures. These catalysts were prepared by a sequential process involving the chelation of cobalt salts and 1,10‐phenanthroline‐based ligands with various substituent groups (phen(X), where X=OH, CH3, H, Br, Cl) onto covalent triazine frameworks (CTFs). By modulating the electron‐donating or electron‐withdrawing properties of the substituent groups on the phen‐based ligands, the electron density surrounding the CoN4 centers was effectively controlled. Our results demonstrated a direct correlation between the catalytic activity of the CoN4 centers and the electron‐donating ability of the substituent group on the phenanthroline ligands. Notably, the catalyst denoted as BCTF−Co‐phen(OH), featuring the electron‐donating OH group, exhibited the highest ORR catalytic activity. This custom‐crafted catalyst achieved a remarkable half‐wave potential of up to 0.80 V vs. RHE and an impressive turnover frequency (TOF) value of 47.4×10−3 Hz at 0.80 V vs. RHE in an alkaline environment. [ABSTRACT FROM AUTHOR]

• Vertically aligned Co-doped MoS 2 nanosheet array is prepared via CVD sulfurization. • The morphology is controlled by tuning CoCl 2 content in CoCl 2 -MoCl 5 precursor film. • The array exposes active edge sites primarily and facilitates electron transport. • Co-atom doping activates in-plane S atoms presenting at splits of nanosheets. A combination of high surface area, fast-speed charge transportation, excellent intrinsic activity, and low material cost is desired for electrocatalysts' applications, such as hydrogen production, counter electrodes of electrochemical solar cells, etc. In this regard, we originally develop a vertically aligned Co-doped MoS 2 nanosheet array via a facile chemical vapour deposition (CVD) approach that utilizes the reaction between drop-coated CoCl 2 -MoCl 5 precursor film and sulfur vapour released from elemental sulfur powder. Such structure that exposes primarily edge sites of the nanosheets provides reaction with more active centers and guarantees that electrons transport almost along high-electron-mobility basal plane of MoS 2. Simultaneously, the catalytic activity of the in-plane S atoms of MoS 2 , exposing at the splits of MoS 2 nanosheets, can be triggered via Co atom-doping. Such an array that is in-situ grown on graphite foil substrate performs as an efficient electrocatalyst for hydrogen evolution reaction with an overpotential of 185 mV at a current density of 10 mA·cm−2 and an extremely high TOF 0.56 s−1 at 200 mV overpotential, meanwhile, sponsoring as a counter electrode for efficient (8.99%) dye-sensitized solar cells. [ABSTRACT FROM AUTHOR]

Abstract Molybdenum disulfide (MoS 2)/sulfur-doped carbon sphere nanohybrid is facilely synthesized via sulfuring a molybdenum chloride–carbon sphere precursor on a flexible graphite paper substrate. Sulfur-doping could enhances the electrocatalytic activity for triiodide reduction. Moreover, there is the existence of atomic and electronic interactions between MoS 2 and S-doped carbon spheres in the nanohybrid composite. Due to the synergistic effect, the microstructure of MoS 2 is much affected, and thus exposing more plane edges and plenty of lattice defects. Besides, the conductivity of the nanohybrid is much improved with the carbon sphere additive. As a result, the dye-sensitized solar cell using the nanohybrid as counter electrode shows higher photoelectric conversion efficiency (7.72%) than those based on pure MoS 2 (6.73%) and platinized F-doped tin oxide rigid glass (6.74%). Highlights • MoS 2 /S-doped carbon is in-situ deposited via a precursor sulfuring approach. • S-dopping affects the composite's microstructure and active. • MoS 2 is vertically grown on the surface of MoS 2 /S-doped carbon sphere film. • There are lots of lattice defects inside the MoS 2 /S-doped carbon sphere film. [ABSTRACT FROM AUTHOR]

Molybdenum disulfide (MoS 2 ) is considered as a promising candidate to Pt-based catalysts. Literatures report the active centers of MoS 2 locate at its edges, while the perfect in-plane domains are not active. In this study, a simple Co Mo S precursor decomposition approach is used to synthesize Co-doped MoS 2 in-situ grown graphite paper (GP) substrate. Electrochemical analyses reveal the Co-doped MoS 2 possesses excellent electrocatalytic activity comparable to Pt. Density functional theory (DFT) calculations indicate the inert in-plane S atoms neighboring the doped Co atoms become active towards triiodide reduction, as revealed by the adsorption energies ( E ad ) of iodine atom decreasing from 0.36 eV to −0.52 eV, identical with value obtained from Pt (−0.52 eV). Due to increased active sites, highly conductive of GP, and excellent electrical connection between Co-doped MoS 2 and GP substrate, the dye-sensitized solar cell fabricated using Co-doped MoS 2 /GP as counter electrode (CE) shows higher photoelectric conversion efficiency (7.26%) than those based on MoS 2 /GP CE (6.57%) and platinized F-doped tin oxide (Pt/FTO) electrode (6.87%). [ABSTRACT FROM AUTHOR]

A low-cost and efficient MoS 2 /graphite paper (GP) counter electrode for dye-sensitized solar cells (DSSCs) is first fabricated by a simple and effective solution processed route. Photo-electric conversion efficiency of 6.48% is obtained for the DSSC adopting MoS 2 /GP, better than the device (6.22%) employing platinized F-doped tin oxide (Pt/FTO) electrode. Because highly conductive GP is performed as a substrate, and the mechanical adhesion and electrical connection between the MoS 2 film and the GP substrate are strong, the series resistance of MoS 2 /GP is much smaller than that of Pt/FTO. A comparable charge transfer resistance of MoS 2 /GP to Pt/FTO is found to be another factor for the better performance. Due to the MoS 2 prepared here possessing relatively high crystallinity and firmly being anchored on the GP substrate, MoS 2 /GP as well exhibits high stability. Hence, excellent electrochemical activity, high stability, facile preparation and low material cost of the MoS 2 /GP electrode offer it a promising potential for large-scale production. [ABSTRACT FROM AUTHOR]

Several nickel cobalt sulfide (Ni-Co-S) counter electrodes (CEs) are prepared, and the Ni-Co-S nanoparticles are in-situ grown on SnO 2 : F (FTO) transparent conductive glasses via a facile solvothermal process, in which thiourea is used as the sulfurizing reagent. The X-ray diffraction, scanning electron microscopy, and energy dispersive spectrometer are employed to measure the microstructure and composition of the Ni-Co-S CEs. When a proper amount of thiourea is adopted, fine crystalline NiCo 2 S 4 CE is obtained. When the amount of thiourea is small or large, (Ni,Co) 4 S 3 or (Ni,Co) 3 S 4 CE is acquired, respectively. Cyclic voltammetry, electrochemical impedance spectroscopy, Tafel polarization and open-circuit voltage decay (OCVD) measurements all demonstrate that the electrocatalytic activities and electrical conductivities of these Ni-Co-S CEs all approach or exceed those of Pt-pyrolysis CE. Their superior electrochemical performances are further confirmed by fabricating DSSCs with the Ni-Co-S CEs, they display similar or better photo-electric conversion efficiencies to/than the Pt-pyrolysis counterpart. [ABSTRACT FROM AUTHOR]

A facile method is developed to prepare NiCo 2 S 4 counter electrode (CE) which is in-situ grown on SnO 2 : F transparent conductive glass (FTO) with mirror-like smooth surface. As demonstrated by analyses, the electrocatalytic activity, electrical conductivity and light reflectivity of the NiCo 2 S 4 CE exceed or approach to those of Pt-sputtering CE, and are much better than those of Pt-pyrolysis CE. Thus the conversion efficiency (η) of the dye sensitized solar cell (DSSC, 8.10%) based on NiCo 2 S 4 CE is higher than the cell based on Pt-sputtering CE (7.60%), and is superior to the one based on Pt-pyrolysis CE (7.01%). Remarkably, NiCo 2 S 4 CE also exhibits excellent chemical and mechanical stability. There are almost no changes on morphology and interfacial adhesion between NiCo 2 S 4 film and FTO substrate after sequential 1000-time scans of cyclic voltammetry and 100 cycles of 3 M Scotch tape detachment. The η of DSSC drops a little from 8.10% to 7.94%. The numerous superiorities of the Pt-sputtering-like NiCo 2 S 4 CE permit its promising application in DSSCs. [ABSTRACT FROM AUTHOR]

TiO 2 pyramids with planar-surface morphology presenting in the phases of anatase and brookite are successfully prepared, the height of which is 300-500 nm and 80-200 nm wide at the bottom. The pyramids exhibit excellent reflectance in the visible-near infrared region. When introducing the pyramids as a scattering layer covering the layer composed of TiO 2 nanoparticles, the energy conversion efficiency of dye-sensitized solar cell (DSSC) is enhanced from 6.49% to 7.25%. However, the pyramids overlayer falls from the nanoparticles underlayer easily, and the fill factor of the DSSC with the pyramids layer also become much lower. To solve the problem, we substitute TiO 2 microspheres underlayer for NP underlayer. As the tips of pyramids could be inserted into the submicron-sized gaps between the TiO 2 microspheres, the interface connection between layers of photoanode is reinforced. Current-Voltage measurement shows that the fill factor of the DSSC is much improved, and the DSSC has achieved 8.35% energy conversion efficiency. This study shows that the novel bilayer photoanode with improved light utilization and interface connection is an interesting structure for high efficiency DSSCs. [ABSTRACT FROM AUTHOR]

In this paper, we prepare a composite-hierarchical microsphere (HMS) which is composed of two kinds of HMSs: one flower-like microsphere (FMS, ∼1.5 μm, containing nanoparticles and nanowires) and plentiful mesoporous submicron ellipsoidal spheres (ESs, ∼200 nm, assembled with nanoparticles) which are embedded evenly in the FMS. For comparing, pure FMS and ES are prepared, respectively. It is found that the composite-HMS possesses (a) the highest BET surface area, (b) the highest light scattering ability, (c) the fastest electron transport and the longest electron life time, and (d) light trapping ability enabled by multiple light reflection and scattering between ESs and nanowires inside each FMS*ESs particle. The energy conversion efficiency of 7.91% of the DSSC based on FMS*ESs is higher than devices based on ES and FMS (7.22% and 7.24%, respectively), which also benefits from the structural advantages of the composite-HMS compared with non-composite HMSs. [ABSTRACT FROM AUTHOR]

Abstract: Light harvesting in dye-sensitized solar cells (DSSCs) mediated by plasmonic metallic nanoparticles and sub-micron light-scattering metal oxides is a facile and cost-effective approach to achieving high device performance. Ag nanoparticles, protected by thin shells of TiO2, were incorporated in TiO2 photoanode. The large plasmonic near-field intensity generated by these nanoparticles caused an 18.3% rise in photocurrent, which resulted in an enhanced efficiency of 6.23% as compared to 5.29% efficiency of DSSC based on unmodified TiO2 photoanode. In addition, DSSC with TiO2 nanofibers (NFs) embedded in TiO2 photoanode was also constructed, which because of the efficient light scattering ability of the nanofibers, attained an efficiency of 7.14% as a result of a current rise of 36.9%. Another DSSC was assembled with Ag NPs added to the photoanode of the NFs-based DSSC to further boost cell performance. The addition of Ag NPs, however, did not produce an appreciable change in the cell performance. The reason for this unexpected outcome was probably due to the low internal resistance associated with charge recombination and large resistance to electron transport in the cell as determined by electrochemical impedance analysis computed in this work. [Copyright &y& Elsevier]

Abstract: The concentration of tetrabutyl titanate (TBT) and H2O influence on the reaction kinetics of TBT and acetic acid (AcOH) solvothermal system are systematically studied. It is found that TBT and H2O have greatly accelerated the hydrolysis–condensation process of the TBT–AcOH system. By adjusting those concentrations with reaction time, we prepare five kinds of sub-micron/micron precursors, which are hierarchical structures consisting of different primary building blocks. The morphology of these precursors varies from noninterlaced structures composed of flower-like microsphere and ellipsoid sphere to interlaced structures composed of flower-like microsphere interlaced nanofibers, ellipsoid spheres interlaced flower-like microsphere and nanoparticles interlaced flower-like microsphere. These interlaced structures are synthesized for the first time and are not ordinary mixtures of the noninterlaced structures. After heat treatment, these precursors are transformed to anatase TiO2. Shape-dependent photovoltaic performances of dye-sensitized solar cells (DSSCs) are also discussed. DSSCs based on these hierarchical sub-micron/micron TiO2 show 7.3%–7.9% energy conversion efficiencies, and the devices based on interlaced structures have higher efficiencies (7.4%–7.9%) than those of the devices based on noninterlaced structures (7.3%–7.6%). [Copyright &y& Elsevier]

Abstract: TiO2 doping has been widely used to improve the performance of dye-sensitized solar cells. In this paper, we study the use of N as a dopant of TiO2 in dye-sensitized solar cells (DSSCs), analyzing the effect on the photovoltaic properties of the cells based on different amounts of N doping. Results indicate that the dye absorption is increased, which would enhance the amount of photoelectron; moreover, the resistance (R 3) of the electron transport within photoelectrode and electron lifetime of it are improved by N doping. The above two reasons would lead the high short circuit current density (J sc). However, owing to the sites of recombination and severe defects introduced, the trend of dye absorption, R 3 and electron lifetime is opposite when the amount of N doping is more than 3%. Finally, we find that the optimal amount of N doing is 3%, which outstandingly increase the performance of DSSCs. The conversion efficiency of the DSSCs can be reached to 6.25% when using the 3% N-doped TiO2 photoelectrode, and this efficiency is 23.03% higher than that of the pure TiO2. [Copyright &y& Elsevier]

Abstract: Trace amount chromium-doped (Cr-doped) TiO2 is prepared by hydrothermal method for dye-sensitized solar cells (DSSCs). The effect on photovoltaic performance of the cells is investigated via control of the concentrations of Cr doped in TiO2. Rutile phase increases when Cr is incorporated into TiO2 while the property of electron transport in photoelectrodes is improved by doping Cr which results in a reduced resistance (R ct) of the electron transport within mesoporous layer and an improved electron lifetime. The regularity of R ct and electron lifetime is reversed when the level of doped Cr exceeds 50 ppm. On the other hand, owing to the doping effect of Cr, the short-circuit photocurrent density (J sc) of DSSCs is remarkably enhanced and reaches maximum. Consequently, the overall energy conversion efficiency enhances to 6.35% with Cr-doped TiO2 of 50 ppm, which is 14.62% higher than that with undoped TiO2. In general, compared with undoped TiO2, Cr-doped TiO2 is a better photoanode material and a more promising alternative for high efficient DSSCs. [Copyright &y& Elsevier]

Abstract: The interaction between ZnO compact layer and TiCl4 post-treatment on TiO2 photoelectrode for dye sensitized solar cell (DSSC) is investigated. Photoelectrode combined the two modifications is designated as ZnO+2l+TiCl4. It is found that after the TiCl4 treatment the ZnO compact layer transforms to a bi-functional layer, which suppresses back electrons transfer from FTO to electrolyte and reduces the FTO/TiO2 interfacial resistance. In addition, the newly formed TiO2 coating generated by TiCl4 post-treatment contains abundant and well dispersed Zn element, which further facilitates electron transfer at TiO2 layer. Meanwhile, the electron lifetime in ZnO+2l+TiCl4 is the longest. Consequently, the overall energy conversion efficiency of the cell with ZnO+2l+TiCl4 is significantly enhanced to 8.9%, which is 8.8% higher than that with pure TiCl4 post-treatment and 17.7% higher than that without any treatment. These results are verified by material characterization and corresponding opto-electrical properties measurements. Experimental results demonstrate this facile method is a more promising alternative to the conventional interface and surface modification in high efficient DSSCs. [Copyright &y& Elsevier]

Sequence-specific interactions between proteins and DNA are essential for a variety of biological functions. The (cytosine-C5)-methyltransferase from HhaI (M.HhaI) specifically modifies the second base in GCGC sequences, employing a base flipping mechanism to access the target base being chemically modified. The mechanism of sequence-specific recognition of M.HhaI is not evident based on crystallographic structures, leading to the suggestion that recognition is linked to the flipping event itself, a process that may be referred to as energetic recognition. Using computational methods, it is shown that the free energy barriers to flipping are significantly higher in non-cognate versus the cognate sequence, supporting the energetic recognition mechanism. Energetic recognition is imparted by two protein “selectivity filters” that function via a “web” of protein–DNA interactions in short-lived, high energy states present along the base flipping pathway. Other sequence-specific DNA binding proteins whose function involves significant distortion of DNA''s conformation may use a similar recognition mechanism. [Copyright &y& Elsevier]

Inhibition of BCR-ABL tyrosine kinase activity has shown to be essential for the treatment of chronic myelogenous leukemia (CML). However, drug resistance has quickly arisen in recent clinical trials for STI571 (Gleevec), which is the first approved drug of CML by inhibiting ABL tyrosine kinase. It is desirable to develop new types of ABL tyrosine kinase inhibitors that may overcome this drug resistance problem. Here we present the discovery of novel inhibitors targeted at the catalytic domain of ABL tyrosine kinase by using three-dimensional database searching techniques. From a database containing 200,000 commercially available compounds, the top 1000 compounds with the best DOCK energy score were selected and subjected to structural diversity and drug likeness analysis, 15 compounds were submitted for biological assay. Eight out of the 15 showed inhibitory activity against K562 cells with IC50 value ranging from 10 to 200 μM. Two promising compounds showed inhibition in further ABL tyrosine phosphorylation assay. It is anticipated that those two compounds can serve as lead compounds for further drug design and optimization. [Copyright &y& Elsevier]

Utilizing two of the Earth's most abundant and inexhaustible resources, sunlight and domestic wastewater, to produce value-added CO presents an immense opportunity. Here, we present a novel strategy to selectively generate CO from domestic wastewater with the aid of concentrated solar power and high-entropy sulfide photocatalysts. Our designed system achieves an impressive CO yield of 35 μmol g−1 h−1 with 100% selectivity, showcasing the feasibility of utilizing solar energy alone to drive the heat-promoted photoreaction. Mechanistic investigations divulged the generation of a non-radical 1O 2 species with a moderate redox potential. This process enables mild oxidation of carbonaceous organic matter in domestic wastewater, rather than complete mineralization of carbonaceous organic matter and reducing greenhouse gas emissions such as CO 2 and CH 4 during organic matter degradation. The findings present an effective and promising approach for low-carbon wastewater treatment, highlighting the potential of CO production from wastewater through solar energy catalysis. Through the rational design of the outdoor photocatalytic equipment, close to 100% selectivity from real domestic wastewater to CO gas was successfully achieved. [Display omitted] • Actual domestic wastewater was treatment of under mild environmental conditions. • Selectivity of the generated CO gas was close to 100% with zero emissions. • Mild oxidation of singlet oxygen (1O 2) results the highly selective formation of CO. [ABSTRACT FROM AUTHOR]

The synthesis of hydrogen peroxide through artificial photosynthesis is a green and promising technology with advantages in sustainability, economy and safety. However, superoxide radical (⋅O2−), an important intermediate in photocatalytic oxygen reduction to H2O2 production, has strong oxidizing properties that potentially destabilize the catalyst. Therefore, avoiding the accumulation of ⋅O2− for its rapid conversion to H2O2 is of paramount significance in improving catalyst stability and H2O2 yield. In this work, a strategy was developed to utilize protonated groups for the rapid depletion of converted ⋅O2−, thereby the efficiency of photocatalytic synthesis of H2O2 from CN was successfully enhanced by 47‐fold. The experimental findings demonstrated that polydopamine not only improved carrier separation efficiency, and more importantly, provided the adsorption reduction active site for ⋅O2− for efficient H2O2 production. This work offers a versatile approach for synthesizing efficient and stable photocatalysts. [ABSTRACT FROM AUTHOR]

The synthesis of hydrogen peroxide through artificial photosynthesis is a green and promising technology with advantages in sustainability, economy and safety. However, superoxide radical (⋅O2−), an important intermediate in photocatalytic oxygen reduction to H2O2 production, has strong oxidizing properties that potentially destabilize the catalyst. Therefore, avoiding the accumulation of ⋅O2− for its rapid conversion to H2O2 is of paramount significance in improving catalyst stability and H2O2 yield. In this work, a strategy was developed to utilize protonated groups for the rapid depletion of converted ⋅O2−, thereby the efficiency of photocatalytic synthesis of H2O2 from CN was successfully enhanced by 47‐fold. The experimental findings demonstrated that polydopamine not only improved carrier separation efficiency, and more importantly, provided the adsorption reduction active site for ⋅O2− for efficient H2O2 production. This work offers a versatile approach for synthesizing efficient and stable photocatalysts. [ABSTRACT FROM AUTHOR]

• Co-N polymer is pyrolyzed with dicyandiamide to synthesize a Co-N-C catalyst. • Carbon nanosheet/nanotube-interweaved structure favors 3D electrical conduct. • Balanced micro/mesopore distribution facilitates mass diffusion. • Atomic and metal Co separately enable excellent ORR and OER performances. • Promising liquid and flexible rechargeable Zn-air batteries are achieved. Developing active and stable non-precious metal bifunctional electrocatalysts towards the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) still remains a crucial challenge. Herein, we propose a simple strategy of integrating atomically dispersed and nanoscaled Co species embedded in micro-/mesoporous carbon nanosheet/nanotube architecture. Revealed by control and SCN- poisoning experiments, N species and atomically dispersed Co species are the main active centers for ORR; whereas the metal Co nanocrystals are the chief active species for OER. Additionally, the balanced micro/mesopore distribution offers fast mass diffusion, and carbon nanosheet/nanotube architecture supplies favorable 3D electrical conduct. As a result, the as-prepared CoNC (1:4) exhibits a positive half-wave potential of 0.87 V (vs RHE) for ORR, and a low potential of 1.55 V (vs RHE) at 10 mA cm−2 for the OER. Importantly, the flexible Zn-air battery using the catalyst exhibits a peak power density of 117 mW cm−2, a higher round-trip efficiency of 68% cycling at 2 mA/cm−2, and an excellent cycling stability with 3% decrease after 126 cycles test. This work provides a general strategy to design bifunctional catalysts by integrating atomically dispersed and nanoscaled transitional metal species together with N-doped micro-/mesoporous 3D carbon. [ABSTRACT FROM AUTHOR]

Exploration high-efficient bifunctional electrocatalysts for oxygen evolution reaction (OER) and oxygen reduction reaction (ORR) is of great significance for several renewable energy applications. In this paper, a catalyst composed of Co 9 S 8 and porous carbon (Co 9 S 8 –C) is prepared first via the calcination of Co–S–C based precursor coating on carbon-fibre-paper (CFP) substrate under argon atmosphere. Then, the Co 9 S 8 –C is modified via the decomposition gas of dicyandiamide, thus Co 9 S 8 –N-doped carbon (Co 9 S 8 -NC) catalyst is synthesized. As revealed, the morphology and defect features are effectively modulated by the modification, suggesting the reduced particle sizes of Co 9 S 8 component and obviously improved N proportion and various defects. As a result, Co 9 S 8 -NC represents excellent activities electrocatalytic performances toward OER and ORR, which surpass those of its three counterparts including Co 9 S 8 –C, Co 9 S 8 , and NC. A half-wave potential of 0.86 ​V versus RHE for ORR and a low overpotential of 280 ​mV ​at 10 ​mA ​cm-2 current density for OER are achieved, with the Δ E value of 0.64 ​V. Additionally, the catalyst also demonstrates desirable application prospect for Zn-air battery. The post-treatment method reported here might be utilized widespread to promote the synergistic effects between the Co-contained particles and N-doped carbons in composite catalysts. The DCA post-treatment can produce high amounts of N-doped pore edges, and can simultaneously facilitate the intimate electronic contact between moderately eroded Co 9 S 8 and N-doped carbon matrix thus forming abundant high active coupling Co-N x -C centers. The catalyst demonstrates excellent bifunctional performance for catalyzing OER and ORR. Image 1 • Co 9 S 8 -porous N-doped carbon (NC) catalyst was in-situ synthesized on CFP substrate. • Intimate electronic contact between Co 9 S 8 and NC is achieved through a dicyandiamide post-treatment. • N content is much improved with rich new-formed pyridinic N and interfacial Co–N. • The catalyst exhibits remarkable OER/ORR bifunction and good prospect in flexible Zn-air battery. [ABSTRACT FROM AUTHOR]

Development of economical, stable and high-efficient electrocatalysts gives vital incentives to promote the large-scale implementation of clean energy devices. Transition metal sulfides and carbon materials provide broad platforms for design of highly active electrocatalysts thanks to their flexibility, high electrical conductivity, and possessing various catalytically active sites towards different reaction systems. Herein, a ternary-component MoS 2 –Co 9 S 8 -NC nanohybrid is synthesized, in which Co 9 S 8 , MoS 2 , and N-doped carbon (NC) are integrated with each other. Owing to forming abundant varied active centers including Co 9 S 8 –MoS 2 heterojunctions, and Co–N, Mo–N coupling centers locating at the contact interfaces between transition metal sulfides and N-doped carbon, the hybrid demonstrates greatly enhanced performances towards hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). Such hybrid represents low overpotentials of 95 mV and 230 mV to achieve 10 mA cm−2 current density for HER and OER in 1.0 M KOH, respectively, and demonstrates favorable prospects for large-scale applications in overall water splitting. Image 1 • MoS 2 –Co 9 S 8 -NC is prepared via a facile precursor-solution-based process. • There are abundant MoS 2 /Co 9 S 8 , Co 9 S 8 /NC and MoS 2 /NC hetero-interfaces. • Abundant interfaces in MoS 2 –Co 9 S 8 -NC facilitate HER and OER performances. • Metal-N bonds are formed at Co 9 S 8 /NC and MoS 2 /NC interfaces with N doping. [ABSTRACT FROM AUTHOR]

Recently, the increasing concerns regarding environmental and energy-related issues due to the use of fossil fuels have triggered extensive research on sustainable electrochemical energy storage and conversion (EESC). In this case, covalent triazine frameworks (CTFs) possess a large surface area, tailorable conjugated structures, electron donating–accepting/conducting moieties, and excellent chemical and thermal stabilities. These merits make them leading candidates for EESC. However, their poor electrical conductivity impedes electron and ion conduction, leading to unsatisfactory electrochemical performances, which limit their commercial applications. Thus, to overcome these challenges, CTF-based nanocomposites and their derivatives such as heteroatom-doped porous carbons, which inherit most of the merits of pristine CTFs, lead to excellent performances in the field of EESC. In this review, initially, we briefly highlight the existing strategies for the synthesis of CTFs with application-targeted properties. Next, we review the contemporary progress of CTFs and their derivatives related to electrochemical energy storage (supercapacitors, alkali-ion batteries, lithium–sulfur batteries, etc.) and conversion (oxygen reduction/evolution reaction, hydrogen evolution reaction, carbon dioxide reduction reaction, etc.). Finally, we discuss perspectives on current challenges and recommendations for the further development of CTF-based nanomaterials in burgeoning EESC research. [ABSTRACT FROM AUTHOR]

Pregnane X receptor (PXR, NR1I2), a member of the nuclear receptor superfamily, is a crucial regulator of nutrient metabolism and metabolic detoxification such as metabolic syndrome, xenobiotic metabolism, inflammatory responses, glucose, cholesterol and lipid metabolism, and endocrine homeostasis. Notably, much experimental and clinical evidence show that PXR senses xenobiotics and triggers the detoxification response to prevent diseases such as diabetes, obesity, intestinal inflammatory diseases and liver fibrosis. In this review we summarize recent advances on remarkable metabolic and regulatory versatility of PXR, and we emphasizes its role and potential implication as an effective modulator of self-detoxification in animals and humans. [ABSTRACT FROM AUTHOR]

As a metal‐free semiconductor photoelectrode material, polymeric carbon nitride (CN) has become one of the research hotspots in the field of photoelectrochemical (PEC) water splitting due to its unique physical and chemical properties. However, high onset potential (Vonset) seriously hinders PEC properties and utilization of solar energy. Herein, boron or phosphor‐doped polymeric carbon nitride (CN−B/P) films are successfully prepared by combining close‐spaced thermal copolymerization with a simple drip coating‐heat treatment method. As a photoanode material, the as‐synthesized doped‐CN films exhibit excellent performance with improved charge injection properties, a longer electron lifetime and reduced flat band potential. Consequently, the photocurrent density of CN−B/P is increased by about 1–3 times compared with pure carbon nitride samples. More importantly, the CN−B and CN−P photoanode both exhibit a very negative Vonset of about 0 V versus reversible hydrogen electrode, which is comparable with the state‐of‐the‐art metal‐based photoanodes. [ABSTRACT FROM AUTHOR]

Structure-based virtual screening (SBVS), also known as molecular docking, has been increasingly applied to discover small-molecule ligands based on the protein structures in the early stage of drug discovery. In this review, we comprehensively surveyed the prospective applications of molecular docking judged by solid experimental validations in the literature over the past fifteen years. Herein, we systematically analyzed the novelty of the targets and the docking hits, practical protocols of docking screening, and the following experimental validations. Among the 419 case studies we reviewed, most virtual screenings were carried out on widely studied targets, and only 22% were on less-explored new targets. Regarding docking software, GLIDE is the most popular one used in molecular docking, while the DOCK 3 series showed a strong capacity for large-scale virtual screening. Besides, the majority of identified hits are promising in structural novelty and one-quarter of the hits showed better potency than 1 μM, indicating that the primary advantage of SBVS is to discover new chemotypes rather than highly potent compounds. Furthermore, in most studies, only in vitro bioassays were carried out to validate the docking hits, which might limit the further characterization and development of the identified active compounds. Finally, several successful stories of SBVS with extensive experimental validations have been highlighted, which provide unique insights into future SBVS drug discovery campaigns. [ABSTRACT FROM AUTHOR]

[Display omitted] • Regulating the proton demand–supply offers a fresh view on improving H 2 O 2 yield. • This work delves into effect of PCHA on H 2 O 2 production increased by 29 times. • The photomechanism was proposed based on a series of tests such as DIRFTS. • The proton regulation route by coating PCHA was applicable to other photocatalysts. In the H 2 O 2 photosynthesis, apart from the charge separation, the balance of proton supply and demand was also required between the kinetically faster oxygen reduction reaction (ORR) (μs ∼ ms) and the sluggish kinetics of water oxidation reaction (WOR) (s). Faced by this challenge, the article designed the heterojunction photocatalyst formed by in-situ polymerization of polyphenol amine on the surface of CdS under alkaline conditions. As a result, the synthesized CdS-Poly(catechol-hexamethylenediamine) (PCHA) produced 6.1 mM H 2 O 2 after 8 h of visible light irradiation, which is 29 times that of CdS. The experimental results evidenced that the coating of PCHA increased the charge separation and mobility, inhibited the photocorrosion of CdS, and thus enhanced the stability and photoactivity. Moreover, the catechol units of PCHA could function as a proton supplier and regulate local protons concentrations around the catalytic active sites to balance the proton supply–demand in the ORR and WOR at different reaction time scales. [ABSTRACT FROM AUTHOR]

Solar-driven photocatalytic H 2 O 2 production is a sustainable and clean technique with respect to the traditional route. Here, the efficient H 2 O 2 generation was accomplished by π−π coupling of AQ onto the few-layered graphitic carbon nitride (g-C 3 N 4) nanoplates through one-step mechanochemical treatment. A H 2 O 2 generation rate of 231 μM h−1 was obtained using AQ-coupled g-C 3 N 4 nanoplates under visible light illumination, exceeding that of the g-C 3 N 4 nanoplates and bulk g-C 3 N 4 by 7-time and 14-time, respectively. Experimental results showed that the high oxygen reduction efficiency could be ascribed to the enhanced surface area, more exposed active sites and the distinct AQ roles of the electrons storage and restraining the charge recombination. This work inspired future work in synthesizing H 2 O 2 through a sustainable and green route. g-C 3 N 4 nanoplates loaded redox molecules were synthesized through a scalable ball milling method. Few-layered structure and AQ coupling can boost the charge separation, offer more active sites and form a more reliable reduction medium (H 2 AQ). [Display omitted] • AQ-coupled g-C 3 N 4 nanoplates were prepared by one-step mechanochemical exfoliation. • The product retained the basic structure and optical properties of g-C 3 N 4 and is fully characterized. • The product showed photocatalytic H 2 O 2 production 14 times better than the bulk in the visible region. • The few-layered structure and AQ coupling led to boosted charge separation, more active sites and reliable reduction medium. [ABSTRACT FROM AUTHOR]

In force field parameter development using ab initio potential energy surfaces (PES) as target data, an important but often neglected matter is the lack of a weighting scheme with optimal discrimination power to fit the target data. Here, we developed a novel partition function-based weighting scheme, which not only fits the target potential energies exponentially like the general Boltzmann weighting method, but also reduces the effect of fitting errors leading to overfitting. The van der Waals (vdW) parameters of benzene and propane were reparameterized by using the new weighting scheme to fit the high-level ab initio PESs probed by a water molecule in global configurational space. The molecular simulation results indicate that the newly derived parameters are capable of reproducing experimental properties in a broader range of temperatures, which supports the partition function-based weighting scheme. Our simulation results also suggest that structural properties are more sensitive to vdW parameters than partial atomic charge parameters in these systems although the electrostatic interactions are still important in energetic properties. As no prerequisite conditions are required, the partition function-based weighting method may be applied in developing any types of force field parameters. © 2013 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Abstract: It is a challenging task to accurately compute the structures and physicochemical properties of partially soluble liquid mixtures using classical force field simulation methods due to the limitations of both sampling and intermolecular potential. In the present study, we employed replica exchange molecular dynamics in combination with the AMOEBA polarizable force field to simulate partially miscible liquid mixtures of dipropylene glycol dimethyl ether and water. We demonstrated that our strategy is promising in studying such complicated binary mixture systems without involving empirical fitting of any available experimental data of mixtures. We correctly predicted the trend of liquid concentration distribution as the function of temperature, and the concentration drifts found in the simulations are consistent with the concentration difference between experimental values and initial configurations. Based on self-diffusion coefficient analysis, the lower critical solution temperature of the system was identified at about 290K, which is in satisfactory agreement with experimental evidence. Although accurate concentration prediction of such a partially miscible system using direct molecular dynamics method remains an intractable task, we expect that such atomistic simulations will play a more important role in future studies of liquid mixtures. [Copyright &y& Elsevier]

Strong intermolecular interaction can prevent an organic molecule from dissolving in a reaction solution, thereby jeopardizing its reactivity and usefulness. Nucleobases and nucleosides (especially many purines and their derivatives) are notoriously difficult to dissolve in most organic solvents, generally attributed to their strong intermolecular interactions caused by the aromaticity, polarity and hydrogen-bonding. Guided by our computational study and prediction, to address this challenge, we have found that by doping the reaction solution with toluene (an inert aromatic compound), the added solvent molecules are capable of generating the stacking interaction with the solute molecules (e.g., purine derivatives) and disrupting the intermolecular stacking of the solute molecules. Thus, this inert doping can successfully address the insoluble challenge, dissolve the poorly soluble reactants (such as purine phosphoramidites), and restore the amidite reactivity for oligonucleotide synthesis. Our research has offered a simple strategy to efficiently synthesize labile oligonucleotides, via disrupting stacking interaction with inert aromatic molecules. [ABSTRACT FROM AUTHOR]

The diabetes-cancer association remains underexplained. Here, we describe a glucose-signaling axis that reinforces glucose uptake and glycolysis to consolidate the Warburg effect and overcome tumor suppression. Specifically, glucose-dependent CK2 O-GlcNAcylation impedes its phosphorylation of CSN2, a modification required for the deneddylase CSN to sequester Cullin RING ligase 4 (CRL4). Glucose, therefore, elicits CSN-CRL4 dissociation to assemble the CRL4COP1 E3 ligase, which targets p53 to derepress glycolytic enzymes. A genetic or pharmacologic disruption of the O-GlcNAc-CK2-CSN2-CRL4COP1 axis abrogates glucose-induced p53 degradation and cancer cell proliferation. Diet-induced overnutrition upregulates the CRL4COP1-p53 axis to promote PyMT-induced mammary tumorigenesis in wild type but not in mammary-gland-specific p53 knockout mice. These effects of overnutrition are reversed by P28, an investigational peptide inhibitor of COP1-p53 interaction. Thus, glycometabolism self-amplifies via a glucose-induced post-translational modification cascade culminating in CRL4COP1-mediated p53 degradation. Such mutation-independent p53 checkpoint bypass may represent the carcinogenic origin and targetable vulnerability of hyperglycemia-driven cancer. [Display omitted] • Glucose-elicited CK2 O-GlcNAcylation impedes CSN2 phosphorylation and CSN-CRL4 binding • Glucose dissociates CSN-CRL4 to assemble the CRL4COP1 E3 for p53 degradation • Glucose-induced p53 depletion amplifies glycometabolism via transcriptional programming • Overnutrition promotes PyMT mammary tumorigenesis via the CRL4COP1-p53 axis Su et al. found that glycometabolism self-amplifies via a glucose-induced post-translational modification cascade culminating in CRL4COP1-mediated degradation of the tumor suppressor p53, thus reinforcing the Warburg effect and overcoming tumor suppression. Such mutation-independent p53 checkpoint bypass may represent the carcinogenic origin and targetable vulnerability of hyperglycemia-driven cancer. [ABSTRACT FROM AUTHOR]

Low‐crystalline nickel sulfide (NiS) nanoparticles are firstly hybridized with single‐crystalline bismuth oxychloride (BiOCl) nanosheets (denoted as NiS/BiOCl) via in‐situ pyrolysis of a NiCl2‐BiCl3‐thiourea precursor at low temperature (250 °C). The idea involved is to combine the functions of low‐crystalline NiS for catalyzing I3− to I− and BiOCl nanosheets for offering fluent charge transport pathway. Especially, in‐situ hybridization leads to close assembly and strong interaction between NiS nanoparticles and BiOCl nanosheets, further enabling the synergetic electronic coupling between the two phases. As a result, the hybrid NiS/BiOCl film can catalyze the reduction of I3− at an extremely low charge transfer resistance of 0.21 Ω cm2, versus 1.63 Ω cm2 for Pt. When used as counter electrode for dye‐sensitized solar cells, device using NiS/BiOCl film as counter electrode produces a high power conversion efficiency of 7.88%, versus 7.35% for Pt under the same conditions. Furthermore, low‐crystalline NiS/BiOCl film can also catalyze oxygen evolution reaction with a current density of 10 mA cm−2 at 1.61 V vs. RHE and a Tafel slope of 113 mV dec−1, which is potentially useful for many operational clean energy devices. Our study thus provides new opportunities for the development of highly efficient hybrid electrocatalyst in a facile and energy‐saving strategy. Low‐crystalline NiS nanoparticles were in‐situ hybridized with single crystalline BiOCl nanosheets via a simple pyrolysis procedure on FTO substrate.The hybrid film exhibits close assembly and strongly interactions between NiS nanoparticles and BiOCl nanosheets. Therefore, it can catalyze the reduction of I3‐ at an extremely low charge transfer resistance of 0.21 Ω cm2, and also catalyze oxygen evolution reaction with a current density of 10 mA cm‐2 at 1.61 V vs. RHE. [ABSTRACT FROM AUTHOR]

A simple, rapid and cost-effective strategy for in situ growing multi-walled carbon nanotubes (MWCNTs) nanocomposites on metal nickel substrates by ethanol flame method with two different precursors is reported to prepare counter electrodes (CEs) of dye-sensitized solar cells (DSSCs). Thiourea is first introduced as a precursor to prepare CNTs with different dimensions and individual carbon-encased sulfide nanoparticles and consuming lower energy in situ preparing process. Then, the diverse structure of as-prepared CNTs samples is explored by observing the reaction process of catalytic growing CNTs. Significantly, both kinds of CNTs nanocomposites in situ growing on nickel foils through flame method are first introduced as CEs in DSSCs, which possessed good conductive properties and excellent electrocatalytic performance. Two corresponding DSSCs based on CNTs CEs display higher fill factor (FF = 0.72, 0.73), larger short-circuit current density (Jsc = 14.1, 14.7 mA cm −2 ) and higher photoelectric conversion efficiency (7.43% and 6.96%) than that (0.69, 13.8 mA cm −2 , 6.72%) of DSSC based on Pt/FTO CE. [ABSTRACT FROM AUTHOR]

The electrocatalytic composite materials of honeycomb structure NiS 2 nanosheets loaded with metallic CoS 2 nanoparticles are in situ prepared on F doped SnO 2 conductive glass (FTO) substrates used as counter electrodes of DSSCs through chemical bath deposition (CBD) and sulfidizing process. Single crystalline NiS 2 honeycomb structure array lay a foundation for the large surface area of NiS 2 /CoS 2 composite CEs. The formed NiS 2 /CoS 2 nanointerface modulates electronic structure of composite CEs from the synergetic interactions between CoS 2 nanoparticles and NiS 2 nanosheets, which dramatically improves the electrocatalytic activity of NiS 2 /CoS 2 composite CEs; Metallic CoS 2 nanoparticles covering NiS 2 nanosheets electrodes adjusts the electrodes' structure and then reduces the series resistance (Rs) and the Nernst diffusion resistance (Zw) of counter electrodes. The improvement of these areas greatly enhances the electrocatalytic performance of CEs and the short circuit current density (Jsc) and Fill factor (FF) of DSSCs. Impressively, the DSSC based on NiS 2 /CoS 2 -0.1 CE shows the best photovoltaic performance with photovoltaic conversion efficiency of 8.22%, which is 24.36% higher than that (6.61%) of the DSSC with Pt CE. And the NiS 2 /CoS 2 -0.1 CE also displays a good stability in the iodine based electrolyte. This work indicates that rational construction of composite electrocatalytic materials paves an avenue for high-performance counter electrodes of DSSCs. [ABSTRACT FROM AUTHOR]

The design and facile fabrication of highly efficient, cost-effective and earth abundant counter electrode material on an electrode surface is highly desirable for the application of dye-sensitized solar cells (DSSCs). Herein, using a N,N-dimethylformamide based solution process, transition metal chalcogenide Ni x S y films have been obtained by spin-coating a NiCl 2 -thiourea (Ni-Tu) solution combining mild thermal treatment. XRD, SEM and TEM characterizations reveal that the current procedure allows for phase composition (Ni 3 S 2 , NiS and NiS-NiS 2 ), crystallinity, morphology (film uniformity and compactness) control of the films through simple adjusting Ni/S ratio in the precursor solution. Electrochemical analysis indicates that the FTO supported Ni 3 S 2 and NiS films exhibit excellent electrocatalytic activity toward the reduction of triiodide, resulting in higher photo-electric conversion efficiencies of 6.86% and 6.95% when used as counter electrode in DSSCs, versus 6.66% for Pt. In particular, even without the support of conductive FTO layer, Hall effect measurements and electrocatalytic analysis reveal that pristine Ni x S y films exhibit good electrical conductivity and electrocatalytic activity, yielding a highest photo-electric conversion efficiency of 4.41% when used as counter electrode in DSSCs. Our study thus provides a facile procedure which allows for composition, morphology optimization and high performance for low-cost, large-scale DSSC application. [ABSTRACT FROM AUTHOR]

Glycolipids are important structural components of biological membranes and perform crucial functions in living systems, including signaling transduction and interaction with extracellular environment. However, the mechanistic exploration of glycolipids in vivo is challenging because they are not genetically encoded. Herein, we designed and synthesized a series of bifunctional monogalactosyldiacylglycerol (MGDG) probes as a model by introducing diazirine and terminal alkyne moieties on an aliphatic chain. In combination with proteome profiling and molecular modeling, we have demonstrated that MGDG alleviates inflammation by antagonizing TLR4. [ABSTRACT FROM AUTHOR]

Glycolipids are important structural components of biological membranes and perform crucial functions in living systems, including signaling transduction and interaction with extracellular environment. However, the mechanistic exploration of glycolipids in vivo is challenging because they are not genetically encoded. Herein, we designed and synthesized a series of bifunctional monogalactosyldiacylglycerol (MGDG) probes as a model by introducing diazirine and terminal alkyne moieties on an aliphatic chain. In combination with proteome profiling and molecular modeling, we have demonstrated that MGDG alleviates inflammation by antagonizing TLR4. [ABSTRACT FROM AUTHOR]

Considering the undesirable electrocatalytic activity toward I − /I 3 − redox system of prinstine antimony sulfide (Sb 2 S 3 ) fabricated with the existing conditions, a mesoporous carbon nanoparticle film (CNP) is introduced here for in-situ growth of Sb 2 S 3 to construct a Sb 2 S 3 @CNP hybrid catalyst. Based on a Sb-thiourea precursor solution, in-situ growth of Sb 2 S 3 can be achieved via solution deposition (denoted as Sb 2 S 3 @CNP-S) as well as atmospheric pressure thermal evaporation (denoted as Sb 2 S 3 @CNP-T) in CNP matrix. Structural characterizations indicate that Sb 2 S 3 particles have well dispersed in the pores of CNP matrix. Because of the introduction of porous and conductive CNP matrix to support Sb 2 S 3 , the hybrid catalyst exhibits lower charge transfer resistance at the catalyst/electrolyte interface and higher electrocatalytic activity. When used as counter electrode (CE) for dye-sensitized solar cells (DSSCs), devices using Sb 2 S 3 @CNP hybrid catalyst as CE produce fill factor of 67.6% and 66.3%, which is significantly higher than that using pristine Sb 2 S 3 fabricated in our previous work (52.8%). Finally, the corresponding power conversion efficiencies reach 6.69% (Sb 2 S 3 @CNP-S) and 6.24% (Sb 2 S 3 @CNP-T), respectively, which are comparable to that using Pt CE measured under the same conditions (6.74%). [ABSTRACT FROM AUTHOR]

[Display omitted] Pim-1 kinase is a serine/threonine kinase which is vital in many tumors. The Pim-1 inhibitor 10-DEBC and its derivatives discovered in our previous work were modified through macrocyclization strategy. A series of benzo[ b ]pyridine[4,3-e][1,4]oxazine macrocyclic compounds were designed, synthesized, and evaluated as novel Pim-1 kinase inhibitors. Among these compounds, compound H5 exhibited the highest activity with an IC 50 value of 35 nM. In addition, the crystal complex structure of Pim-1 kinase bound with compound H3 was determined, and the structure–activity relationship of these macrocyclic compounds was analyzed, which provides the structural basis of further optimization of novel macrocyclic Pim-1 kinase inhibitors.. [ABSTRACT FROM AUTHOR]

[Display omitted] Pim-1 kinase is a serine/threonine kinase which is vital in many tumors. The Pim-1 inhibitor 10-DEBC and its derivatives discovered in our previous work were modified through macrocyclization strategy. A series of benzo[ b ]pyridine[4,3-e][1,4]oxazine macrocyclic compounds were designed, synthesized, and evaluated as novel Pim-1 kinase inhibitors. Among these compounds, compound H5 exhibited the highest activity with an IC 50 value of 35 nM. In addition, the crystal complex structure of Pim-1 kinase bound with compound H3 was determined, and the structure–activity relationship of these macrocyclic compounds was analyzed, which provides the structural basis of further optimization of novel macrocyclic Pim-1 kinase inhibitors.. [ABSTRACT FROM AUTHOR]

The currently circulating Omicron sub-variants are the SARS-CoV-2 strains with the highest number of known mutations. Herein, we found that human angiotensin-converting enzyme 2 (hACE2) binding affinity to the receptor-binding domains (RBDs) of the four early Omicron sub-variants (BA.1, BA.1.1, BA.2, and BA.3) follows the order BA.1.1 > BA.2 > BA.3 ≈ BA.1. The complex structures of hACE2 with RBDs of BA.1.1, BA.2, and BA.3 reveal that the higher hACE2 binding affinity of BA.2 than BA.1 is related to the absence of the G496S mutation in BA.2. The R346K mutation in BA.1.1 majorly affects the interaction network in the BA.1.1 RBD/hACE2 interface through long-range alterations and contributes to the higher hACE2 affinity of the BA.1.1 RBD than the BA.1 RBD. These results reveal the structural basis for the distinct hACE2 binding patterns among BA.1.1, BA.2, and BA.3 RBDs. [Display omitted] • Omicron BA.1.1 and BA.2 show higher binding strength to hACE2 than the prototype and BA.1 • Details in the binding interface of BA.1.1, BA.2, and BA.3.RBD with hACE2 are deciphered • R346K in BA.1.1 RBD enhances the interaction with hACE2 through long-range alterations The biochemical and structural analysis of the human angiotensin-converting enzyme-2 (ACE2, the receptor for SARS-CoV-2 viral entry) and the receptor-binding domain (RBD) of four Omicron sub-variants—BA.1, BA.1.1, BA.2, and BA.3—helps to reveal the structural basis of differences in sub-variant binding affinities and the impact of RBD mutations. [ABSTRACT FROM AUTHOR]

[Display omitted] • A series of atomically dispersed Sb-N-C catalysts are prepared via a facile adsorption-pyrolysis strategy. • Atomically dispersed Sb are stabilized by N atoms in terms of Sb-N 5 configuration. • Self-evaporation of Sb during synthesis could create abundant micro/meso-pores. • Sb-N 5 sites enable Sb-N-C catalysts outstanding oxygen reduction reaction activity. • Abundant micro/ meso -pores enable Sb-N-C catalysts enhanced mass transport. Main-group metal based single-atom catalysts are attracting increasing research attention in electrochemical catalysis owing to their partially occupied valence p-orbitals. Herein, we report a series of atomically dispersed Sb-N-C catalysts (including Sb-N-C NP , Sb-N-C NL and Sb-N-C NT) synthesized by a facile adsorption-pyrolysis strategy for oxygen reduction reaction (ORR). Apart from generating atomically dispersed Sb-N 5 sites as active centers, self-evaporation of Sb during pyrolysis process has created abundant micro/meso-pores in Sb-N-C catalysts. Benefitting from these advantageous features, Sb-N-C presents outstanding ORR activity (Sb-N 5 sites) and efficient mass transport (micro/meso-pores). By rotating disk electrode (RDE) test in alkaline media, Sb-N-C exhibits a most positive half-wave potential of 0.90 V vs. RHE and a highest kinetic current density up to 43.8 mA cm−2 at 0.85 V vs. RHE. As gas diffusion electrode (GDE), Sb-N-C NP0.2 demonstrates fast O 2 diffusion and transport that enables smaller mass transport overpotential at high current densities up to 800 mA cm−2. Finally, Zn-air battery that uses the Sb-N-C NP catalyst as air electrode achieves a maximum power density of 180 mW cm−2 and more than 1000 hs of continuous operation. This work further demonstrates the excellent performance of main-group Sb single-atom catalyst toward ORR and applications in practical energy conversion devices. [ABSTRACT FROM AUTHOR]

Cobalt sulfide counter electrodes for the dye-sensitized solar cell (DSSC) were successfully prepared on fluorine-doped tin oxide (FTO) glass substrates by a facial one-step in situ solvothermal method. The influences of prepared temperature on the synthesized phase, surface morphology, electrocatalytic, and photovoltaic performances of the cobalt sulfide counter electrodes were investigated with X-ray diffraction (XRD), field-emission scanning electron microscopy (SEM), cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), Tafel, and photocurrent density-voltage ( J- V) measurements. The results indicated that very thin CoS nanoparticle thin films grew on the FTO substrates and the CoS counter electrode prepared at 180 °C showed superior electrocatalytic activity, chemical stability, and photovoltaic performance. The DSSC based on the CoS counter electrode prepared at 180 °C exhibited an efficiency of 6.59 % which was comparable to the solar cell based on the sputtering Pt counter electrode (6.82 %). It indicated that CoS in situ growing on FTO glass substrate at 180 °C is a potential candidate to replace Pt as a low-cost and efficient counter electrode of DSSC. [ABSTRACT FROM AUTHOR]

Summary The regulatory role of N 6 -methyladenosine (m 6 A) and its nuclear binding protein YTHDC1 in pre-mRNA splicing remains an enigma. Here we show that YTHDC1 promotes exon inclusion in targeted mRNAs through recruiting pre-mRNA splicing factor SRSF3 (SRp20) while blocking SRSF10 (SRp38) mRNA binding. Transcriptome assay with PAR-CLIP-seq analysis revealed that YTHDC1-regulated exon-inclusion patterns were similar to those of SRSF3 but opposite of SRSF10. In vitro pull-down assay illustrated a competitive binding of SRSF3 and SRSF10 to YTHDC1. Moreover, YTHDC1 facilitates SRSF3 but represses SRSF10 in their nuclear speckle localization, RNA-binding affinity, and associated splicing events, dysregulation of which, as the result of YTHDC1 depletion, can be restored by reconstitution with wild-type, but not m 6 A-binding-defective, YTHDC1. Our findings provide the direct evidence that m 6 A reader YTHDC1 regulates mRNA splicing through recruiting and modulating pre-mRNA splicing factors for their access to the binding regions of targeted mRNAs. [ABSTRACT FROM AUTHOR]

Herein, we report a one-step hydrothermal procedure to prepare ZnS-CoS microcomposite which was employed as counter electrode (CE) for dye-sensitized solar cells (DSSCs). The microcomposite exhibits a morphology with ZnS microspheres decorated with CoS nanoparticles, and the decoration effect on electrocatalytic activity of prinstine ZnS toward I − /I 3 − redox couple was investigated with cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and Tafel polarization measurements. Experimental results show that ZnS-CoS microcomposite exhibits remarkably enhanced electrocatalytic activity compared with that of pristine ZnS in catalyzing the reduction of I 3 − , and the electrocatalytic activity enhancement closely depends on Co/Zn molar ratio. As a result, the optimized DSSC using ZnS-CoS with a Co/Zn molar ratio of 3: 7 as CE exhibits a highest power conversion efficiency of 6.11%, in comparison with the reference device using Pt CE which shows an efficiency of 7.27%. The enhanced performance compared with DSSC using pristine ZnS CE which has an efficiency of 0.59% can be attributed to the introduction of more electrocatalytic active sites in ZnS-CoS microcomposite. Our study thus provides an effective approach to improve electrocatalytic activity of ZnS and proves its potential suitability as CE for the fabrication of DSSCs. [ABSTRACT FROM AUTHOR]

Sb 2 S 3 film was prepared on conductive substrate FTO via a facile process combining a hydrothermal procedure and post-annealing treatment, which was directly used as counter electrode (CE) for dye-sensitized solar cells (DSSCs). Electrochemical characterizations demonstrate that the as-prepared Sb 2 S 3 film exhibits sufficient electrocatalytic activity and stability for catalyzing the oxidation/reduction of triiodide to iodide. When used as CE in DSSCs, device using Sb 2 S 3 CE that obtained after 24 h of hydrothermal reaction achieves a maximum power conversion efficiency of 5.37%, equal to that using Pt CE (5.36%). Our study thus provides a highly desirable approach for preparing cheap and highly efficient Pt-free CEs for DSSCs, which has avoided the complicated electrode deposition procedure and large amount of material consumption. [ABSTRACT FROM AUTHOR]

Herein, we report a bilayer TiO 2 photoanode composed of nanocrystalline TiO 2 (NCT) bottom layer and mixed P25 nanoparticles and large rutile particles (PR) top scattering layer. The present structure performs well in solar light harvesting which is mainly attributed to the fact that the top scattering layer exhibits superior light scattering effect and meanwhile the NCT bottom layer with large dye-loading capacity can make better use of the back-scattered light. Moreover, electrochemical impedance spectroscopy and open circuit voltage decay measurements demonstrate that DSSC based on bilayer photoanode shows faster interfacial electron transfer and slower charge recombination process than that based on NCT monolayer photoanode. These advantages render the DSSCs based on NCT-PR bilayer photoanode exhibiting superior performance under AM1.5G simulated solar irradiation. As an example, by tuning mass ratio between P25 nanoparticles and large rutile particles in the top scattering layer, the DSSC based on NCT-PR bilayer photoanode exhibits an optimum solar energy conversion efficiency of 9.0%, which is about 1.25 times higher than that of monolayer NCT device (7.2%) with the same film thickness. [ABSTRACT FROM AUTHOR]