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Utilizing single atom sites doping into metal oxides to modulate their intrinsic active sites, achieving precise selectivity control in complex organic reactions, is a highly desirable yet challenging endeavor. Meanwhile, identifying the active site also represents a significant obstacle, primarily due to the intricate electronic environment of single atom site doped metal oxide. Herein, a single atom Cu doped TiO2catalyst (Cu1-TiO2) is prepared viaa simple “colloid-acid treatment” strategy, which switches aniline oxidation selectivity of TiO2from azoxybenzene to nitrosobenzene, without using additives or changing solvent, while other metal or nonmetal doped TiO2did not possess. Comprehensive mechanistic investigations and DFT calculations unveil that Ti-O active site is responsible for triggering the aniline to form a new PhNOH intermediate, two PhNOH condense to azoxybenzene over TiO2catalyst. As for Cu1-TiO2, the charge-specific distribution between the isolated Cu and TiO2generates unique Cu1-O-Ti hybridization structure with nine catalytic active sites, eight of them make PhNOH take place spontaneous dissociation to produce nitrosobenzene. This work not only unveils a new mechanistic pathway featuring the PhNOH intermediate in aniline oxidation for the first time but also presents a novel approach for constructing single-atom doped metal oxides and exploring their intricate active sites.

In this paper, the effects of hot isostatic pressing (HIP) and heat treatment (HT) on the stress rupture properties of nickel-based superalloy K417G were investigated. Scanning electron microscopy (SEM), electron backscatter diffraction (EBSD) and transmission electron microscopy (TEM) were employed to analyze the microstructure, fracture morphology, determination of crack source and dislocation evolution after stress rupture fracture. The results indicate that, HIP specimens demonstrate a 19.5% reduction in stress rupture life compared to as-cast specimens, whereas HIP + HT specimens exhibit a 41% increase in stress rupture life, reaching a value of 63.04 h. The fracture mechanism of the samples under different heat treatment conditions is different. There are a large number of pores in the as-cast specimen, which leads to the initiation and propagation of cracks and eventually result in fracture. The pores in the HIP specimen are almost eliminated. However, the coarsening and uneven distribution of γ′ phase led to the weakening of the hindrance to dislocation movement. Additionally, the increase in elongated carbides at grain boundaries accelerates crack initiation and propagation. Under HIP and HT, the cubic γ′ phase is uniformly precipitated, which effectively hinders the movement of dislocation lines. Granular M23C6carbides precipitate at grain boundaries, acting as pinning points to retard grain boundary sliding and crack propagation, thus improving the stress rupture life.

Electrocatalytic refinery of low-value biomass-based glycerol into value-added chemicals formic acid (FA) is an attractive alternative to traditional thermochemical refineries. However, constructing non-precious catalysts with abundant active hydroxyl (OH*) is the main obstacle to the electrocatalytic glycerol oxidation reaction (EGOR). Herein, we combine density functional theory (DFT) and experiments to investigate EGOR over the finely constructed NiCo2O4nanosheets. DFT results firstly indicate that the NiCo2O4nanosheets exhibit the highly hydroxylated (311)-OH* surface with the lowest Gibbs free energy, which significantly improves the electrochemical reaction kinetics and can achieve desirable FA yield by adjusting the adsorption energy of the adsorption intermediate. Following the theoretical prediction, ultrathin NiCo2O4nanosheets (~1.70 nm) are fabricated by a facile electrodeposition method with sufficient OH* on the surface. The charge-transfer resistance of NiCo2O4nanosheets in EGOR is only 0.94 Ω and the anode power consumption can be reduced by up to 320 mV at 10 mA cm−2, keeping the high glycerol conversion (89%) and FA selectivity (70%) during the 120-h stability test. DFT calculations and experimental tools (e.g., multi-potential step experiments, operational electrochemical impedance spectroscopy) confirm that OH* in-situgenerated on the thin nanosheets structure is essential in facilitating charge transfer between catalysts and adsorbed molecules to enhance C–C bond cleavage. This work offers a guideline for the rational design of robust catalysts for the selective upgrading of biomass-derived chemicals.

While Stimulator-of-interferon genes (STING) is an innate immune adapter cruicial for sensing cytosolic DNA and modulating immune microenvironment, its tumor-promoting role in tumor survival and immune evasion remains largely unknown. Here we reported that renal cancer cells are exceptionally dependent on STING for survival and evading immunosurveillance via suppressing ER stress-mediated pyroptosis. We found that STING is significantly amplified and upregulated in clear cell renal cell carcinoma (ccRCC), and its elevated expression is associated with worse clinical outcomes. Mechanically, STING depletion in RCC cells specifically triggers activation of the PERK/eIF2α/ATF4/CHOP pathway and activates cleavage of Caspase-8, thereby inducing GSDMD-mediated pyroptosis, which is independent of the innate immune pathway of STING. Moreover, animal study revealed that STING depletion promoted infiltration of CD4+and CD8+T cells, consequently boosting robust antitumor immunity via pyroptosis-induced inflammation. From the perspective of targeted therapy, we found that Compound SP23, a PROTAC STING degrader, demonstrated comparable efficacy to STING depletion both in vitro and in vivo for treatment of ccRCC. These findings collectively unveiled an unforeseen function of STING in regulating GSDMD-dependent pyroptosis, thus regulating immune response in RCC. Consequently, pharmacological degradation of STING by SP23 may become an attractive strategy for treatment of advanced RCC.

ABSTRACTIntroductionBacterial synthetic biology has provided powerful tools to revolutionize the drug discovery process. These tools can be harnessed to generate bacterial novel pharmaceutical compounds with enhanced bioactivity and selectivity or to create genetically modified microorganisms as living drugs.Areas coveredThis review provides a current overview of the state-of-the-art in bacterial synthetic biology tools for novel drug discovery. The authors discuss the application of these tools including bioinformatic tools, CRISPR tools, engineered bacterial transcriptional regulators, and synthetic biosensors for novel drug discovery. Additionally, the authors present the recent progress on reprogramming bacteriophages as living drugs to fight against antibiotic-resistant pathogens.Expert opinionThe field of using bacterial synthetic biology tools for drug discovery is rapidly advancing. However, challenges remain in developing reliable and robust methods to engineer bacteria. Further advancements in synthetic biology hold promise to speed up drug discovery, facilitating the development of novel therapeutics against various diseases.

Objectives: To evaluate whether venous tumor thrombus (VTT) consistency is a risk factor for the patient’s prognosis with renal cell carcinoma (RCC). Materials and methods: A total of 190 RCC patients with VTT, who were treated at Department of Urology, Chinese PLA General Hospital, were retrospectively analyzed in this study. The baseline clinical characteristics, postoperative outcomes, and pathological findings were analyzed. Tumor thrombus was classified as solid and friable based on their respective characteristics. Survival curves were estimated using the Kaplan–Meier survival curve analysis, and univariable and multivariable cox proportional hazard regression models were used. Results: Among the total 190 patients included in this study, 145 (76.3%) patients had solid VTT, and 45 (23.7%) patients had friable VTT in their renal veins and inferior vena cava (IVC). There were no significant differences in the age, gender, BMI, symptoms, complex diseases, tumor side, tumor size, TNM stage, Mayo stage, tumor grade, sarcomatous differentiation, pelvic invasion, and sinus fat invasion of patients. Solid VTT consistency was more likely to have a capsule as compared to those with friable VTT (P= 0.007). Kaplan–Meier survival curve analysis demonstrated no statistically significant differences in the overall survival (OS) (P= 0.973) and progression-free survival (PFS) (P= 0.667) of patients. Moreover, VTT consistency was not associated with OS (P= 0.706) of PFS (P= 0.504) in multivariate cox regression analysis. Conclusions: RCC VTT consistency was not a prognostic risk factor for predicting the OS and PFS of patients.

In the conversion process of syngas-to-C2species, the OH species are inevitably produced accompanying the production of key intermediates CHx(x = 1–3), traditionally, the function of surface OH species is generally accepted as the hydrogenating reactive species. This work for the first time proposed and confirmed the assisted catalytic mechanism of surface OH species that performed as the promoter for syngas-to-C2species on Cu-based catalysts. DFT and microkinetic modeling results reveal that the produced OH species accompanying the intermediates CHxproduction on the MCu (M = Co, Fe, Rh) catalysts can stably exist to form OH/MCu catalysts, on which the presence of surface OH species as the promoter not only presented better activity and selectivity toward CHx(x = 1–3) compared to MCu catalysts, but also significantly suppressed CH3OH production, providing enough CHxsources to favor the production of C2hydrocarbons and oxygenates. Correspondingly, the electronic properties analysis revealed the essential relationship between the electronic feature of OH/MCu catalysts and catalytic performance, attributing to the unique electronic micro−environment of the catalysts under the interaction of surface OH species. This new mechanism is called as OH-assisted catalytic mechanism, which may be applied in the reaction systems related to the generation of OH species.

In order to make up for the shortage of scientific research experiments and teaching in land-based engine room laboratory, a simulation system is designed and developed using B/S mode to simulate scientific research experiments, teaching and operation processes, and designed algorithms to simulate the propulsion characteristics of the main propulsion diesel engine. A large number of experiments were carried out, and the relationship curve between output power and fuel consumption rate of the main engine was obtained in the laboratory. Apache JMeter was used to test the pressure of the simulation system deployed in Dalian Maritime University Cloud. It is found that under the test conditions, the average response time of sample request is 330 ms, which is far superior the design standard of 2 s. There is no abnormal response to all requests, and all indicators fully meet the requirements of the project team. The simulation system fills the gap in the application of panoramic interactive technology in Marine engineering education, and provides a reference for the exploration of "intelligent +" experiment and teaching mode in maritime university laboratories.

Pt-based catalysts as the commercial catalysts in ethane dehydrogenation (EDH) face one of the main challenges of realizing the balance between coke formation and catalytic activity. In this work, a strategy to drive the catalytic performance of EDH on Pt–Sn alloy catalysts is proposed by rationally engineering the shell surface structure and thickness of core–shell Pt@Pt3Sn and Pt3Sn@Pt catalysts from a theoretical perspective. Eight types of Pt@Pt3Sn and Pt3Sn@Pt catalysts with different Pt and Pt3Sn shell thicknesses are considered and compared with the industrially used Pt and Pt3Sn catalysts. Density functional theory (DFT) calculations completely describe the reaction network of EDH, including the side reactions of deep dehydrogenation and C–C bond cracking. Kinetic Monte Carlo (kMC) simulations reveal the influences of the catalyst surface structure, experimentally related temperatures, and reactant partial pressures. The results show that CHCH* is the main precursor for coke formation, and Pt@Pt3Sn catalysts generally have higher C2H4(g) activity and lower selectivity compared to those of Pt3Sn@Pt catalysts, which is attributed to the unique surface geometrical and electronic properties. 1Pt3Sn@4Pt and 1Pt@4Pt3Sn are screened out as catalysts exhibiting excellent performance; especially, the 1Pt3Sn@4Pt catalyst has much higher C2H4(g) activity and 100% C2H4(g) selectivity compared to those of 1Pt@4Pt3Sn and the widely used Pt and Pt3Sn catalysts. The two descriptors C2H5* adsorption energy and reaction energy of its dehydrogenation to C2H4* are proposed to qualitatively evaluate the C2H4(g) selectivity and activity, respectively. This work facilitates a valuable exploration for optimizing the catalytic performance of core–shell Pt-based catalysts in EDH and reveals the great importance of the fine control of the catalyst shell surface structure and thickness.

Previous audio-text retrieval (ATR) methods primarily concentrate on constructing contrastive pairs between entire audio clips and full caption sentences, while neglecting fine-grained cross-modal relationships. In this letter, we first introduce a weighted token-level alignment (WTA) module for ATR to learn fine-grained semantic interactions. Besides, due to the unavailability of manually labeling the fine-grained sequential correspondence between audio-text pairs, we attempt to model ATR as a cooperative game process to flexibly handle the uncertainty during audio-text semantic interactions. Specifically, we treat audio frames and text words as players and present a game theoretic interaction (GTI) method to assess potential correspondence between audio frames and text words, which can also be seen as an additional learning signal to improve the pure audio-text contrastive learning. Furthermore, to implement multi-level WTA and GTI, we develop a token cluster module to cluster the frames/words and calculate the interaction scores between the clustered tokens. Experiments show that our WTA significantly improves the ATR performance on multiple datasets. By combining our GTI, the retrieval performance is further boosted by a large margin.

Subsurface chemistry in heterogeneous catalysis plays an important role in tuning catalytic performance. Aiming to unravel the role of subsurface heteroatoms, C2H2semihydrogenation on a series of Pd catalysts doped with subsurface heteroatom H, B, C, N, P, or S was fully investigated by density functional theory (DFT) calculations together with microkinetic modeling. The obtained results showed that catalytic performance toward C2H2semihydrogenation was affected significantly by the type and coverage of subsurface heteroatoms. The Pd-B0.5and Pd-C0.5catalysts with 1/2 monolayer (ML) heteroatom coverage, as well as Pd-N, Pd-P, and Pd-S catalysts with 1/16 ML heteroatom coverage, were screened to not only obviously improve C2H4selectivity and activity but also effectively suppress green oil. The essential reason for subsurface heteroatoms in tuning catalytic performance is attributed to the distinctive surface Pd electronic and geometric structures caused by subsurface heteroatoms. In the Pd-B0.5and Pd-C0.5catalysts, the Pd surface electronic and geometric effects play the dominant role, while the geometric effect plays a key role in the Pd-N, Pd-P, and Pd-S catalysts. The findings provide theoretically valuable information for designing high-performance metal catalysts in alkyne semihydrogenation through subsurface chemistry.

To effectively avoid the drawbacks of conventional metal-based electromagnetic interference (EMI) shielding materials such as high density and susceptibility to corrosion, a multifunctional melamine foam (MF) consisting of MXene/polydimethylsiloxane (PDMS) layers with ultralow percolation thresholds was designed through the electrostatic self-assembly and impregnation strategies. The prepared lightweight foams simultaneously show multifunctional properties including EMI shielding, infrared (IR) stealth, oxidation-resistance, and compression stability. Typically, this multifunctional foam exhibits an excellent EMI shielding efficiency (EMI SE) of 45.2 dB at X-band (8.2–12.4 GHz) with only 1.131 vol % MXene filler. Moreover, the temperature difference between the upper and lower surfaces of the foam can be maintained at 45 °C due to its unique three-dimensional (3D) porous structure and low infrared emissivity. The MF skeleton with MXene/PDMS (MFMXP) displays high hydrophobicity, which remains stable in EMI SE after 60 days of exposure to air. Additionally, it shows outstanding mechanical stability after 100 cycles of compression experiments. The lightweight stealth nanocomposite foams can operate stably in complex environments and show high potential for applications in high-tech fields such as wearable electronics, the military, and semiconductors, etc.

Clear cell renal cell carcinoma (ccRCC) is one of the most common malignant tumors and is characterized by a poor prognosis. Although G2- and S -phase expressed-1 (GTSE1) is known to be involved in the progression and metastasis of various cancers, its significance and mechanism in ccRCC remain unknown. In the present study, we found that GTSE1 was overexpressed in ccRCC tissues, especially in metastatic samples. Moreover, high GTSE1 expression was positively correlated with higher pT stage, tumor size, clinical stage, and WHO/ISUP grade and worse prognosis. And GTSE1 expression served as an independent prognostic factor for overall survival (OS). In addition, GTSE1 knockdown inhibited ccRCC cell proliferation, migration, and invasion, and enhanced cell apoptosis in vitro and in vivo. GTSE1 was crucial for epithelial–mesenchymal transition (EMT) in ccRCC. Mechanistically, GTSE1 depletion could upregulate the expression of Krüppel-like factor 4 (KLF4), which acts as a tumor suppressor in ccRCC. Downregulation of KLF4 effectively rescued the inhibitory effect induced by GTSE1 knockdown and reversed the EMT process. Overall, our results revealed that GTSE1 served as an oncogene regulating EMT through KLF4 in ccRCC, and that GTSE1 could also serve as a novel prognostic biomarker and may represent a promising therapeutic target for ccRCC.

Rely on the density functional theory (DFT) calculation, the catalytic performance of PdxCuy/GDY (x = 1, 2, 3, 4; x + y ≤ 4) for CO oxidative coupling reaction was obtained. The Pdx/GDY (x = 1, 2, 3, 4) are not ideal catalyst for dimethyl oxalate (DMO) formation because by-product dimethyl carbonate (DMC) is easily formed on Pd1/GDY and Pd2/GDY, and high activation energies are needed on Pd3/GDY and Pd4/GDY. Therefore the second metal Cu is doped to regulate the performance of Pdx/GDY (x = 1, 2, 3, 4). Doping Cu not only improve the activity of DMO formation, but more importantly, controlling the ratio of Cu:Pd can effectively regulate the selectivity of DMO. Thus taking into account the activity and selectivity of the reaction for the preparation of DMO by CO oxidative coupling, the Pd1Cu1/GDY and Pd1Cu2/GDY with the activation energies of 105.2 and 99.2 kJ mol−1to generate DMO show excellent catalytic activity and high DMO selectivity, which are considered as good catalysts for CO oxidative coupling. The differential charge density analysis shows the decrease in the charge density of metal clusters is an important reason for improving the selectivity of the catalyst.

Whole-cell biosensors for arsenic contamination are typically designed based on natural bacterial sensing systems, which are often limited by their poor performance for precisely tuning the genetic response to environmental stimuli. Promoter design remains one of the most important approaches to address such issues. Here, we use the arsenic-responsive ArsR-Parsregulation system from Escherichia coliMG1655 as the sensing element and coupled gfpor lacZas the reporter gene to construct the genetic circuit for characterizing the refactored promoters. We first analyzed the ArsR binding site and a library of RNA polymerase binding sites to mine potential promoter sequences. A set of tightly regulated Parspromoters by ArsR was designed by placing the ArsR binding sites into the promoter’s core region, and a novel promoter with maximal repression efficiency and optimal fold change was obtained. The fluorescence sensor PlacV-ParsOC2constructed with the optimized ParsOC2promoter showed a fold change of up to 63.80-fold (with green fluorescence visible to the naked eye) at 9.38 ppb arsenic, and the limit of detection was as low as 0.24 ppb. Further, the optimized colorimetric sensor PlacV-ParsOC2-lacZwith a linear response between 0 and 5 ppb was used to perform colorimetric reactions in 24-well plates combined with a smartphone application for the quantification of the arsenic level in groundwater. This study offers a new approach to improve the performance of bacterial sensing promoters and will facilitate the on-site application of arsenic whole-cell biosensors.

Improving the selectivity and activity of C2species from syngas is still a challenge. In this work, catalysts with monolayer Cu or Rh supported over WC with different surface terminations (M/WC (M = Cu or Rh)) are rationally designed to facilitate C2species generation. The complete reaction network is analyzed by DFT calculations. Microkinetics modeling is utilized to consider the experimental reaction temperature, pressure, and the coverage of the species. The thermal stabilities of the M/WC (M = Cu or Rh) catalysts are confirmed by AIMD simulations. The results show that the surface termination and supported metal types in the M/WC (M = Cu or Rh) catalysts can alter the existence form of abundant CHx(x= 1–3) monomer, as well as the activity and selectivity of CHxmonomer and C2species. Among these, only the Cu/WC–C catalyst is screened out to achieve outstanding activity and selectivity for C2H2generation, attributing to that the synergistic effect of the subsurface C atoms and the surface monolayer Cu atoms presents the noble-metal-like character to promote the generation of CHxand C2species. This work demonstrates a new possibility for rational construction of other catalysts with the non-noble metal supported by the metal carbide, adjusting the surface termination of metal carbide and the supported metal types can present the noble-metal-like character to tune catalytic performance of C2species from syngas.

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Introduction: This aim of this study was to delineate current clinical scenarios of painful diabetic peripheral neuropathy (PDN) and associated anxiety and depression among patients in Mainland China, and to report current therapy and clinical practices. Methods: A total of 1547 participants were enrolled in the study between 14 June 2018 and 11 November 2019. Recruitment was conducted using a multilevel sampling method. Participants’ demographics, medical histories, glucose parameters, Douleur Neuropathique 4 Questionnaire (DN4) scores, visual analogue scale (VAS) pain scores, Patient Health Questionnaire 9 (PHQ-9) scores, Generalised Anxiety Disorder 7 (GAD-7) scores and therapies were recorded. Results: The male-to-female ratio was 1.09:1 (807:740), and the mean age at onset was 61.28 ± 11.23 years. The mean DN4 score (± standard deviation) was 4.91 ± 1.88. The frequencies of DN4 sub-item phenotypes were: numbness, 81%; tingling, 68.71%; pins and needles, 62.90%; burning, 53.59%; hypoaesthesia to touch, 50.16%; electronic shocks, 43.31%; hypoaesthesia to pinprick, 37.94%; brushing, 37.82%; painful cold, 29.61%; and itching, 25.86%. Age, diabetic duration, depression history, PHQ-9 score and GAD-7 score were identified as risk factors for VAS pain score. Peripheral artery disease (PAD) was a protective factor for VAS pain score. For all participants currently diagnosed with PDN and for those previously diagnosed PDN, fasting blood glucose (FBG) was a risk factor for VAS; there was no association between FBG and VAS pain score for PDN diagnosed within 3 months prior to recruitment. Utilisation rate of opium therapies among enrolled participants was 0.71% , contradiction of first-line guideline recommendation for pain relief accounted for 9.43% (33/350) and contradiction of second-line guideline recommendation for opium dosage form was 0.57% (2/350). Conclusion: Moderate to severe neuropathic pain in PDN was identified in 73.11% of participants. Age, diabetic duration, depression history, PHQ-9 score, GAD-7 score and FBG were risk factors for VAS pain scores. PAD was protective factor. The majority of pain relief therapies prescribed were in accordance with guidelines. Trial registration: ClinicalTrials.gov identifier, NCT03520608, retrospectively registered, 2018-05-11.

Designing cheap, earth-abundant, and nontoxic metal catalysts for acetylene hydrogenation is of pivotal importance, but challenging. Here, a nonprecious metal catalyst for selective hydrogenation of acetylene in excess ethylene was prepared from Cu2O nanocubes. The preparation includes two steps: (1) thermal treatment in acetylene-containing gas at 160 °C and (2) hydrogen reduction at 180 °C. The resultant catalyst showed outstanding performance at low temperature (80–100 °C) and 0.1–0.5 MPa pressure, completely converting acetylene with a low selectivity to undesired ethane (<20%). The characterization results of high-resolution transmission electron microscopy (HRTEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy corroborated that the formation of an interstitial copper carbide (CuxC) might give rise to significantly enhanced hydrogenation activity. Preliminary density functional theory calculation demonstrated that the lattice spacing of Cu3C was nearly identical to that of the new CuxC crystallite measured in HRTEM and determined by XRD. The calculated dissociation energy of hydrogen on Cu3C(0001) was considerably lower than that on Cu(111), suggesting superior hydrogenation activity of Cu3C(0001). It is experimentally verified that copper(I) acetylide (Cu2C2) might be the precursor of CuxC. Cu2C2underwent partial hydrogenation to fabricate CuxC crystallites and the thermal decomposition to Cu and carbon materials in parallel.

Due to their intrinsic safety, low cost, and eco-friendliness, aqueous Zn-ion batteries (ZIBs) have shown significant potential for wearable and flexible electronic devices. However, the lack of a stable and durable electrolyte for flexible ZIBs greatly hampers their applications in harsh conditions during daily use. In this work, we reported a stable hydrogel electrolyte, fabricated by coupling the grafted copolymer xanthan gum–polyacrylamide (XG–PAM) with cotton cellulose nanofiber (CNF), denoted XG–PAM/CNF. The designed XG–PAM/CNF hydrogel electrolyte exhibited high ionic conductivity (28.8 mS cm–1), good adhesion, high mechanical strength, and strong ion adsorption. In addition, it also shows an inhibition effect on the generation of dendrites. The flexible ZIBs with the XG–PAM/CNF hydrogel electrolyte achieved high specific capacity (237 mA·h g–1) and excellent cycling stability (86.2% retention over 1000 cycles at 4 C). Notably, flexible ZIBs withstand severe conditions, such as bending, folding, poking, washing, soaking, and underwater usage. Furthermore, an underwater warning rescue system application was proposed. Consequently, this work provides a new approach and application for the development of reliable and durable wearable energy storage devices.

This paper focuses on the design and simplification computation of the optimal filter based on the HVS model for PenTile RGB. After simplifying, the proposed method is also easy to implement in hardware. Simulation results show that the optimal filter obtained by mathematical optimization can suppress the color fringing artifacts and improve apparent resolution.

In clinical practice, objective basis for the choice between laparoscopic partial nephrectomy (LPN) and robot-assisted partial nephrectomy (RAPN) is scarce. To evaluate surgical outcomes, assess the individual benefit from LPN to RAPN, which can guide clinical decision-making.

For the sake of understanding deeply the formation of the ethanol from CO hydrogenation on the rhodium-based catalyst, the investigation on the relationship of the activity–structure for CO dissociation on Rh metal surface is necessary. Here, the effect of FCC and HCP Rh crystal phases and Rh surfaces on CO dissociation is predicted through DFT calculations, the equilibrium crystal shapes, and microkinetic modeling. The calculated overall activation barriers show that the H-assisted pathway with the relatively lower barrier energies is favorable compared with the direct one, which is independent of Rh crystal phases and surfaces. Among different FCC and HCP Rh surfaces, the (100) surface exhibits the highest CO dissociation activity with the relative reaction rate of 1.28 × 1011, which is at least 105times those on other surfaces. The CO dissociation activity of FCC Rh depends on (100) and (111) while that of HCP Rh depends on (0001), (10–12), and (10–10). The CO conversion rate on FCC Rh is about 104times that on HCP Rh, suggesting that FCC Rh has a higher activity than HCP Rh. Moreover, the quantitative study shows that CO dissociation is primarily dependent on the electronic effect on Rh surfaces by the barrier decomposition method. PDOS, COHP, differential charge density, and Mulliken and Loewdin charges were further analyzed. Finally, this study can be expected to enrich the knowledge of the activity–structure of CO dissociation on Rh catalyst and provide a valuable guide for designing efficient Rh catalyst to improve CO conversion.

This research is designed to fundamentally understand CO activation acting as a crucial step in the initiation of the Fischer–Tropsch (FT) process over Co2C catalyst, the intrinsic activity, and structural sensitivity of the catalyst, which is vital to its FT performance, but remains unclear. Accordingly, CO activation over the commonly exposed Co2C(101), (011), (010), (110), and (111) facets is investigated using density functional theory (DFT) calculations and microkinetic modeling. Results show that the CH monomer is the most abundant surface CHxspecies for CO activation over five Co2C facets, and the mechanism of CO activation and subsequent CH formation strongly depend on the Co2C facet. The formation rate of the CH monomer follows the order of (111) < (010) < (110) < (101) < (011). The (011) facet accounting for 35.21% of the surface is the most active for CO direct dissociation into C, followed by C hydrogenation to CH, which presents a comparable activity with the hexagonal close-packed (HCP) Co due to the presence of denser B5-type active sites. Further, Co2C is a multifunctional catalyst for the FT process because its facets exhibit a different catalytic activity toward CO dissociation to form the key CH monomer, and as a result, C2+hydrocarbons and oxygenates can be formed depending on the relative reaction rate between CO insertion into CHxreaction and CHx–CHxcoupling. The finding of this research may lead a new avenue for rational design of Co2C-based catalysts with desirable activities and product selectivity.

Supplemental Digital Content is available in the text.

Whole-cell and cell-free transcription-translation biosensors have recently become favorable alternatives to conventional detection methods, as they are cost-effective, environmental friendly, and easy to use. Importantly, the biological responses from the biosensors need to be converted into a physicochemical signal for easy detection, and a variety of genetic reporters have been employed for this purpose. Reporter gene selection is vital to a sensor performance and application success. However, it was largely based on trial and error with very few systematic side-by-side investigations reported. To address this bottleneck, here we compared eight reporters from three reporter categories, i.e., fluorescent (gfpmut3, deGFP, mCherry, mScarlet-I), colorimetric (lacZ), and bioluminescent (luxCDABEfrom Aliivibrio fischeriand Photorhabdus luminescens, NanoLuc) reporters, under the control of two representative biosensors for mercury- and quorum-sensing molecules. Both whole-cell and cell-free formats were investigated to assess key sensing features including limit of detection (LOD), input and output dynamic ranges, response time, and output visibility. For both whole-cell biosensors, the lowest detectable concentration of analytes and the fastest responses were achieved with NanoLuc. Notably, we developed, to date, the most sensitive whole-cell mercury biosensor using NanoLuc as reporter, with an LOD ≤ 50.0 fM HgCl230 min postinduction. For cell-free biosensors, overall, NanoLucand deGFPled to shorter response time and lower LOD than the others. This comprehensive profile of diverse reporters in a single setting provides a new important benchmark for reporter selection, aiding the rapid development of whole-cell and cell-free biosensors for various applications in the environment and health.

To compare the upgrade rate and cancer detection rate between 18F-DCFPyL PET/MRI-guided ultrasound fusion targeted biopsy and systematic biopsy in selected patients with suspected prostate cancer (the multiparametric MRI prostate imaging reporting and data system score ≥4 and molecular imaging prostate-specific membrane antigen score of prostate-specific membrane antigen PET image ≥2).

The selective hydrogenation of C2H2on five types of Cu(0)/Cu(I), Cu(0), Cu(I), PdCu(0), and PdCu(I) catalysts are investigated to illuminate the effects of Cu component and the promoter on the selectivity and activity toward C2H4formation. The selectivity and activity toward C2H4formation on five types of catalysts are examined using density functional theory calculations. The results indicate that Cu(0)/Cu(I) bicomponent catalyst presents higher selectivity but significantly lower activity toward C2H4formation compared to the individual Cu(0) or Cu(I) catalysts, suggesting that Cu(0)/Cu(I) bicomponent catalyst cannot be selected as an ideal catalyst applied to the selective hydrogenation of C2H2, namely, the catalytic activity of Cu catalyst toward C2H4formation dominates on the single-component rather than the multicomponent. On the other hand, for the promoter Pd-modified Cu(0) or Cu(I) bimetallic catalysts, PdCu(I) catalyst presents poor selectivity toward C2H4formation compared to the individual Cu(I) catalyst, whereas PdCu(0) catalyst exhibits better selectivity and activity toward C2H4formation compared to the individual Cu(0) catalyst, indicating that the promoter-modified Cu catalysts should focus on the Cu(0) catalyst rather than the Cu(I) catalyst. The results not only understand the reaction theories associated with the experimental results but also provide the basic theoretical clues for designing more efficient Cu-based catalysts applied in the selective hydrogenation of C2H2.

A series of core–shell catalysts aiming at CO oxidative coupling to dimethyl oxalate (DMO) were constructed, and effects of the second metal doping and surface structures on the reaction activity and favorable reaction path were investigated by using the density functional theory (DFT) method. Pd13, Al@Pd12, and Ag@Pd12were first studied to find the proper doping metal. Our results showed that the activity of CO oxidative coupling to DMO follows the order of Al@Pd12> Pd13> Ag@Pd12, and the same result was also obtained via the electronic analysis. In addition, Al6@Pd32and Al13@Pd42catalysts with higher doping ratio and lower cost than that of Al@Pd12were selected to examine the influence of surface structure on the reaction activity. It showed that CO + CH3O → COOCH3+ CO → OCCOOCH3+ CH3O → DMO is the favorable pathway on the (100) surface of Al6@Pd32catalyst, while CO + CH3O → CO + CH3O (COOCH3) → COOCH3+ COOCH3→ DMO is the optimal pathway on the (111) surface of Al@Pd12and Al13@Pd42, which indicated that the surface structure of catalysts affected the preferable pathway of DMO formation. Moreover, activities of CO oxidative coupling to DMO on AlPd core–shell catalysts followed the order of Al@Pd12> Al13@Pd42> Al6@Pd32. In addition, Al13@Pd42also exhibited a good selectivity between DMO and DMC. Thus, Al13@Pd42is a proper catalyst with high activity, high selectivity, and low cost because of high Al:Pd ratio.

Pd-based catalysts are extensively employed to catalyze CO oxidative coupling to generate DMO, while the expensive price and high usage of Pd hinder its massive application in industrial production. Designing Pd-based catalysts with high efficiency and low Pd usage as well as expounding the catalytic mechanisms are significant for the reaction. In this study, we theoretically predict that Pd stripe doping Co(111) surface exhibits excellent performance than pure Pd(111), Pd monolayer supporting on Co(111) and Pd single atom doping Co(111) surface, and clearly expound the catalytic mechanisms through the density functional theory (DFT) calculation and micro-reaction kinetic model analysis. It is obtained that the favorable reaction pathway is COOCH3–COOCH3coupling pathway over these four catalysts, while the rate-controlling step is COOCH3+CO+OCH3→2COOCH3on Pd stripe doping Co(111) surface, which is different from the case (2COOCH3→DMO) on pure Pd(111), Pd monolayer supporting on Co(111) and Pd single atom doping Co(111) surface. This study can contribute a certain reference value for developing Pd-based catalysts with high efficiency and low Pd usage for CO oxidative coupling to DMO.

ABSTRACTBackgroundNon-responsiveness is a major barrier in current cancer immune checkpoint blockade therapies, and the mechanism has not been elucidated yet. Therefore, it is necessary to discover the mechanism and biomarkers of tumor immunotherapeutic resistance.MethodsBioinformatics analysis was performed based on CD8+T cell infiltration in multiple tumor databases to screen out genes related to anti-tumor immunity. Associations between Regulator of G-protein signaling 1 (RGS1) and IFNγ-STAT1 signaling, and MHCI antigen presentation pathway were examined by RT-qPCR, western blotting, and flow cytometry. The modulatory mechanisms of RGS1 were investigated via CHIP-qPCR and dual-luciferase assay. The clinical and therapeutic implications of RGS1 were comprehensively investigated using tumor cell lines, mouse models, and clinical samples receiving immunotherapy.ResultsRGS1 was identified as the highest gene positively correlated with immunogenicity among RGS family. Inhibition of RGS1 in neoplastic cells dampened anti-tumor immune response and elicited resistance to immunotherapy in both renal and lung murine subcutaneous tumors. Mechanistically, RGS1 enhanced the binding of activating transcription factor 3 (ATF3) to the promoter of interferon gamma receptor 1 (IFNGR1), activated STAT1 and the subsequent expression of IFNγ-inducible genes, especially CXCL9 and MHC class I (MHCI), thereby influenced CD8+T cell infiltration and antigen presentation and processing. Clinically, lower expression level of RGS1 was associated with resistance of PD1 inhibition therapy and shortened progression-free survival among 21 NSCLC patients receiving immunotherapy.ConclusionsTogether, these findings uncover a novel mechanism that elicits immunotherapy resistance and highlight the function of tumor-intrinsic RGS1, which brings new insights for future strategies to sensitize anti-PD1 immunotherapy.

The purpose of this study was to compare perioperative and oncologic outcomes between laparoscopic radical cystectomy (LRC) and robot-assisted radical cystectomy (RARC) for bladder cancer (BCa).

Aiming at probing into the role of the interface between Cu and Mo2C for syngas conversion to C2oxygenates over the Cu/β-Mo2C catalyst, the formation mechanism of C2oxygenates from syngas over the Cu/β-Mo2C catalyst has been systematically investigated using density functional theory calculations. The results show that the CH monomer is the most preferred CHxspecies formed via the route of CO direct dissociation into C, followed by C hydrogenation to CH; moreover, the Cu/β-Mo2C(001) catalyst presents higher activity and selectivity toward CH formation instead of CH3OH formation. For C2oxygenate formation, CHO insertion into CH to form the C2oxygenate CHCHO is the most preferred. Compared to the pure Cu(111) and β-Mo2C(001), Cu/β-Mo2C(001) exhibits better selectivity toward CH formation, and has the strong ability of C–C chain growth for C2oxygenate formation. On the other hand, the analysis of electronic and structural properties indicates that there is a strong charge transfer between Cu and Mo2C to form a charge-rich region at the interface of the Cu/β-Mo2C(001) catalyst, which promotes the C–O bond cleavage of CO and CHO to form the CH monomer adsorbed at the interface, and favors the subsequent CHO insertion into CH to form the C2oxygenate CHCHO at the interface. As a result, the synergistic effect including the electronic and geometric effect that occurred at the interface between Cu and β-Mo2C(001) leads to high productivity toward C2oxygenates in syngas conversion over the Cu/β-Mo2C(001) catalyst.

Aiming at identifying the effects of the surface structure and composition for the Rh-Cu bimetallic catalysts on the catalytic performance in syngas conversion to C2oxygenates, the mechanism of CO initial activation and the carbon chain formation were systematically investigated using density functional theory calculations. Four model surfaces (RhCu(111) and (211) with Cu-rich or Rh-rich) were examined. The results showed that the preferred way of CO activation is the H-assisted mechanism to form CHO over four types of model surfaces. The carbon chain formation revealed the key factors between the surface structure and composition affecting catalytic activity and selectivity of Rh-Cu bimetallic catalysts toward C2oxygenates formation in syngas conversion, and the surface structure of Rh-rich catalysts only alters the activity and selectivity of C2oxygenates and cannot substantially affect the type of the main product (C2oxygenates). C2hydrocarbons and oxygenates are the main products on the Cu-rich catalysts, and the product selectivity depends on the surface structure. Analysis of d-band centers of Cu and Rh atoms shows that the catalytic performance of Rh-Cu(111) and (211) with Cu-rich or Rh-rich surfaces is closely related to the electronic property. Thus, compared to the Cu-rich surface, the Rh-rich surface of the Rh-Cu bimetallic catalyst is more suitable for the carbon chain formation of C2oxygenates from syngas in which the synergetic interaction between Rh and Cu facilitates the CHO reaction with CHxto form C2oxygenates, and Cu inhibits CHxself-coupling and hydrogenation to form the hydrocarbons. Our study provides a method for the design of high-performance catalysts by controlling the surface structure and composition.

Background Rupture of cerebral aneurysm is an inevitable complication during embolization, followed by subsequent acute subarachnoid hemorrhage or intracranial hematoma, and results in the aggravation of a patient’s condition. In particular, for patients who have had a ruptured aneurysm, urgent treatment strategies are required during operation. The most common hemostatic methods seen in clinical practices are as follows: after lowering the blood pressure, we continue to embolize the aneurysms with detachable coils as soon as possible or inject with Glubran/Onyx embolization liquids, as well as use a balloon catheter to temporarily block the blood supply. If the conditions are permissible, a balloon guiding catheter may even be used to restrict the proximal blood flow. At times, due to limitations of these methods, neurosurgeons are requested to perform craniotomy to treat the hemostasis. However, the delayed transition often leads to rapid deterioration of the patient’s condition and even death due to cerebral hernia.Case description We herein presented two cases of ruptured cerebral aneurysms to provide an alternative method for hemostasis and to save the lives of patients as much as possible. In an extremely urgent situation (conventional treatment is ineffective), we successfully saved the patient’s life by injecting lyophilizing thrombin powder (LTP) solution into the aneurysmal sac and the parent artery through a microcatheter.Conclusions To our knowledge, this is the first report of successful hemostasis during coil embolization of ruptured cerebral aneurysm with LTP. Further prospective studies are needed to confirm the safety and efficacy of LTP in cerebrovascular interventional therapy.

To clarify the effects of the composition and nanocluster size of the core–shell catalysts on C2H4selectivity and activity in C2H2selective hydrogenation, the kinetic mechanisms of C2H2selective hydrogenation over different compositions of M@Pd (M = Au, Ag, and Cu) and M@Cu (M = Au, Ag, and Pd) nanoclusters with different sizes are investigated using density functional theory calculations. The results suggest that the composition and nanocluster size of the core–shell catalyst affect C2H4selectivity and activity, and Cu as the core for M@Pd catalysts exhibits excellent C2H4selectivity and activity than that of Au and Ag; moreover, M@Pd catalysts show better C2H4selectivity and activity than M@Cu. Namely, the core–shell nanocluster catalyst with Cu as the core and Pd as the shell is beneficial to improve C2H4selectivity and activity in C2H2selective hydrogenation. On the other hand, C2H4selectivity and activity increase over M@Pd catalysts with the increase in the nanocluster size, which means that it is necessary to have the catalyst with a larger cluster size in the preparation of Cu@Pd core–shell catalysts. The electronic structure analysis revealed the microscopic reasons about the effects of core–shell catalyst compositions and nanocluster size on the catalytic performance of C2H2selective hydrogenation. This study can provide theoretical guidance for the design of core–shell nanocluster catalysts to improve C2H4selectivity and activity in C2H2selective hydrogenation by adjusting the composition and nanocluster size in an efficient way.

Cell-based biosensors have great potential to detect various toxic and pathogenic contaminants in aqueous environments. However, frequently they cannot meet practical requirements due to insufficient sensing performance. To address this issue, we investigated a modular, cascaded signal amplifying methodology. We first tuned intracellular sensory receptor densities to increase sensitivity, and then engineered multi-layered transcriptional amplifiers to sequentially boost output expression level. We demonstrated these strategies by engineering ultrasensitive bacterial sensors for arsenic and mercury, and improved detection limit and output up to 5,000-fold and 750-fold, respectively. Coupled by leakage regulation approaches, we developed an encapsulated microbial sensor cell array for low-cost, portable and precise field monitoring, where the analyte can be readily quantified via displaying an easy-to-interpret volume bar-like pattern. The ultrasensitive signal amplifying methodology along with the background regulation and the sensing platform will be widely applicable to many other cell-based sensors, paving the way for their real-world applications.

Limited data exist on VTE risk and prophylaxis in Chinese inpatients. The Identification of Chinese Hospitalized Patients’ Risk Profile for Venous Thromboembolism-2 (DissolVE-2), a nationwide, multicenter, cross-sectional study, was therefore designed to investigate prevalence of VTE risks and evaluate VTE prophylaxis implementation compliant with the latest prophylaxis guidelines (American College of Chest Physicians [CHEST], 9th edition).

The effect of Co2C crystal facets on the selectivity of C2species (C2oxygenates and hydrocarbons) in Fischer–Tropsch synthesis (FTS) reaction was investigated using density functional theory calculations, and the selectivity comparisons among five exposed Co-termination (101), (011), (010), (110), and (111) crystal facets are examined to shed light on the essential relationship between FTS selectivity and the structure of Co2C crystal facets. The results show that the C–C bond of C2species prefers to be formed instead of C1species CH4over Co2C catalysts in the FTS reaction, and the selectivity of C2species and the dominant existence form of key CHxintermediates are sensitive to the crystal facet of Co2C catalysts, which are closely associated with Co2C crystal facet’s electronic and structural properties. The electronic and structural properties of different Co2C crystal facets show that the high selectivity of C2oxygenates over the (011) and (111) facets are attributed to the upshift of their surface d-band centers, as well as the presence of the step B5-type active unit with five Co atoms consisted of much denser surface active sites. However, both (101) and (010) facets exhibit high selectivity toward C2hydrocarbons, and the (110) facet presents high selectivity toward the formation of CH4. Thus, regulating the exposed crystal facets of Co2C catalyst can control the selectivity of desirable C2species. This work provides evidence at a molecular level to support that the sensitivity of Co2C crystal facet is a cause to affect the selectivity of desired products in the FTS reaction.

InP-based photonic integrated circuits (PICs) have aroused great interest in recent years to meet the needs of future high-capacity and high-performance optical systems. With the advantages of small size, low power consumption, low cost, high reliability, InP-based PICs are promising solutions to replace the multiple discrete devices used in various systems. In this paper, we will review the design, fabrication, key integration technology and performance of several kinds of InP-based monolithically integrated transmitters developed in our group in recent years. Particular attention will be paid to the electro-absorption modulated laser (EML), multi-wavelength distributed feedback (DFB) laser arrays, widely tunable distributed reflector (DBR) lasers and their arrays, integrated amplified feedback lasers (AFL), and few-mode transmitters.

With the aid of activated carbon, a series of mesoporous ZnO/SiO2sorbents are fabricated by sol–gel method and characterized by X-ray diffraction (XRD), Fourier transform infrared (FTIR), N2adsorption and desorption, scanning electron microscopy and energy dispersive X-ray (SEM-EDX), transmission electron microscopy (TEM), and photoluminescence (PL) spectra. The dynamic tests for H2S capture show that the prepared materials with the aid of AC exhibit excellent performance for H2S capture. The highest sulfur capacity of ZSC-X reaches to 160.95 mgS/g sorbent and the corresponding ZnO utilization is up to 69.02%. The enhanced performance is attributed to AC, which has double roles in this study: anchor and confine ZnO to get highly dispersed small nanoparticles; produce more oxygen vacancies in ZnO to facilitate lattice diffusion. The formation mechanism of well dispersed ZnO nanoparticles is also elucidated. The simply fabricating method of sorbents with high ZnO loading and high utilization is of significance for industrial application of ZnO in H2S removal at room temperature.

KCNJ5 mutation is a major cause of aldosterone-producing adenomas (APAs). The development of APA apart from KCNJ5 mutation is less investigated.

PURPOSE:To evaluate the efficacy and safety of antiangiogenic agents (sorafenib and sunitinib) as postoperative adjuvant therapy in patients with nonmetastatic renal cell carcinoma (RCC) and venous tumor thrombus (VTT). MATERIAL AND METHODS:From March 2006 to January 2016, 147 patients who met the inclusion criteria were enrolled; 27 patients received sorafenib, and 17 patients received sunitinib. After radical nephrectomy and thrombectomy, the duration of maintenance targeted medication treatment was approximately 1 year. The primary objective was to compare disease-free survival (DFS) between each experimental group and control. Secondary end points included overall survival (OS) and toxic effects. RESULTS:The three groups were well balanced in terms of age, body mass index, gender, performance status, medical history, American Society of Anesthesiologists score, surgical approach, and tumor side and size. However, more patients receiving adjuvant therapy had inferior vena cava tumor thrombus. DFS and OS did not differ significantly between groups (P=.459 and .871, respectively). After adjusting for potential confounding factors, results of multivariate analysis proved that postoperative adjuvant therapy was not an independent factor for predicting DFS and OS (P>.05 for both). The subgroup analyses for inferior vena cava tumor thrombus found similar results. The common adverse events were hand-foot syndrome, diarrhea, fatigue, and neutropenia. The adverse effects were mild in both groups, and the incidence was not significantly different between sorafenib and sunitinib. CONCLUSIONS:Adjuvant treatment postoperatively with sorafenib or sunitinib showed no survival benefit relative to control for patients with nonmetastatic RCC and VTT in a prospective cohort study.

Reporting in Cell Reports Physical Science, Ding and co-workers have discovered higher CO conversion and fuel selectivity in a yolk-shell catalyst (Co-Mn@SiO2) as a result of closer nanoparticle contact than atom-doping and separated nanoparticles in Fischer-Tropsch synthesis (FTS). This research advances the development of high-performance FTS catalysts by controlling promoter-active-site intimacy.

Supplemental Digital Content is available in the text.

A periodic density functional theory (DFT) calculation has been used to study the NO reduction by H2on the stepped Pd(211) surface. The main route of N2generation changes with temperature increasing. The dimer path is main for the formation of N2at low temperature, in which two NO react and generate N2O2, and then N2O2decompose to produce N2. However, the active N path becomes main to generate N2via NO hydrogenate and dissociate to produce active N at high temperature. The formation of NH3is via the successive hydrogenation of N or NH. Additionally, energy barriers showed that the Pd(211) surface exhibited higher catalytic activity to the reduction of NO by H2than that on the Pd(111) surface, and the kinetics showed that the selectivity of N2is higher than that of NH3on the stepped Pd(211) surface below about 500 K.

The therapeutic potential of bacteriophages has been debated since their first isolation and characterisation in the early 20thcentury. However, a lack of consistency in application and observed efficacy during their early use meant that upon the discovery of antibiotic compounds research in the field of phage therapy quickly slowed. The rise of antibiotic resistance in bacteria and improvements in our abilities to modify and manipulate DNA, especially in the context of small viral genomes, has led to a recent resurgence of interest in utilising phage as antimicrobial therapeutics. In this article a number of results from the literature that have aimed to address key issues regarding the utility and efficacy of phage as antimicrobial therapeutics utilising molecular biology and synthetic biology approaches will be introduced and discussed, giving a general view of the recent progress in the field. Advances in molecular biology and synthetic biology have enabled rapid progress in the field of phage engineering, with this article highlighting a number of promising strategies developed to optimise phages for the treatment of bacterial disease. Whilst many of the same issues that have historically limited the use of phages as therapeutics still exist, these modifications, or combinations thereof, may form a basis upon which future advances can be built. A focus on rigorous in vivotesting and investment in clinical trials for promising candidate phages may be required for the field to truly mature, but there is renewed hope that the potential benefits of phage therapy may finally be realised.

DFT calculations, together with microkinetic modeling, have been employed to probe into the preferred mechanism of hydrocarbon C–C chain growth on Co(10−11) surfaces during Fischer–Tropsch synthesis. The results show that both CH and CH2are favored CHx(x= 1–3) monomers, and are much easier to be formed than CH4and CH3OH. CH and CH2self-coupling viaa carbide mechanism realizes the initial C–C chain formation, rather than viaa CO/CHO insertion mechanism. Meanwhile, CH3CH2is the favored C2monomer, and is predominantly formed viaa carbide mechanism rather than viaa CO/CHO insertion mechanism, leading to C2H5OH formation. Starting from CH3CH2intermediates, CH3CH2coupling with CH2to form CH3CH2CH2realizes further C–C chain growth from C2to C3species, instead of a CO/CHO insertion mechanism leading to C3H7OH formation. Thus, the proposed mechanism of C–C chain growth is that RCH2CH2coupling with CH2to R′CH2CH2(R′ = RCH2) realizes C–C chain growth. Meanwhile, CHO insertion into RCH2CH leads to RCH2CHCHO, followed by its hydrogenation to an alcohol. However, microkinetic modeling shows that the effect of CH4formation on the production of C2+hydrocarbons should be considered, whereas alcohols have a negligible effect on the selectivity of C2+hydrocarbons. Our results confirm that Co(10−11) surfaces exhibit a better catalytic activity and selectivity toward C2+hydrocarbon formation.

The catalytic selectivity, the functions of a TiO2support and promoter, and the mechanism of ethanol synthesis from syngas on a Rh/TiO2model catalyst have been fully identified. Our results show that all species preferentially interact with Rh7clusters of a Rh/TiO2catalyst, rather than the support and cluster–support interface. CO → CHO → CH2O → CH3O is an optimal pathway. CH3formed viathe CH3O → CH3+ O route is the most favored CHx(x= 1–3) monomer, and this route is more favorable than methanol formation by CH3O hydrogenation; CO insertion into CH3can then form CH3CO, followed by successive hydrogenation to ethanol. Methane is formed by CH3hydrogenation. The Rh/TiO2catalyst exhibits better catalytic activity and selectivity toward CH3than CH3OH formation. Starting from the CH3species, CH4formation is more favorable than CH3CO formation; thus, ethanol productivity and selectivity on a Rh/TiO2catalyst with a support is determined only by CH4formation, which is similar to that on a pure Rh catalyst without a support. Introducing an Fe promoter into the Rh/TiO2catalyst effectively suppresses methane production, and promotes CH3CO formation. Therefore, compared to a pure Rh catalyst without a support, the TiO2support serves only to promote the activity and selectivity of CH3formation, and provide more CH3species for ethanol formation; methane formation is independent of the Rh catalyst support, and depends only on the promoter. In order to achieve high ethanol productivity and selectivity, an effective Rh-based catalyst must contain a suitable combination of supports and promoters, in which the promoter, M, should have characteristics that draw the d-band center of the MRh/TiO2catalyst closer to the Fermi level compared to the Rh7/TiO2catalyst; as a result, the MRh/TiO2catalyst can suppress CH4production and facilitate C2oxygenate formation.