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This article studies how vertical integration and upstream R&D subsidy affect innovation and welfare in vertically separated industries. I formulate a dynamic structural model of a dominant upstream firm and oligopolistic downstream firms that invest in complementary innovations. I estimate the model using data on the System-on-Chip (SoC) and smartphone industries. The results suggest that a vertical merger can increase innovation and welfare, mainly driven by the investment coordination of the merged firms. I also find that subsidizing the upstream innovation increases overall private investment, innovation, and welfare.

Single-atom catalysts, especially those with metal−N 4 moieties, hold great promise for facilitating the oxygen reduction reaction. However, the symmetrical distribution of electrons within the metal−N 4 moiety results in unsatisfactory adsorption strength of intermediates, thereby limiting their performance improvements. Herein, we present atomically coordination-regulated Co single-atom catalysts that comprise a symmetry-broken Cl−Co−N 4 moiety, which serves to break the symmetrical electron distribution. In situ characterizations reveal the dynamic evolution of the symmetry-broken Cl−Co−N 4 moiety into a coordination-reduced Cl−Co−N 2 structure, effectively optimizing the 3 d electron filling of Co sites toward a reduced d -band electron occupancy ( d 5.8  →  d 5.28 ) under reaction conditions for a fast four-electron oxygen reduction reaction process. As a result, the coordination-regulated Co single-atom catalysts deliver a large half-potential of 0.93 V and a mass activity of 5480 A g metal −1 . Importantly, a Zn-air battery using the coordination-regulated Co single-atom catalysts as the cathode also exhibits a large power density and excellent stability. The electrochemical oxygen reduction reaction plays an important role in new energy technologies such as fuel cells and metal-air batteries. Here the authors present a cobalt catalyst with a symmetry-broken Cl−Co−N 4 moiety capable of dynamically modulating electron occupancy at active sites during practical reaction conditions to optimize oxygen reduction performance.

Although the acidic oxygen evolution reaction (OER) plays a crucial role in proton-exchange membrane water electrolysis (PEMWE) devices, challenges remain owing to the lack of efficient and acid-stable electrocatalysts. Herein, we present a low-iridium electrocatalyst in which tensile-strained iridium atoms are localized at manganese-oxide surface cation sites (TS-Ir/MnO 2 ) for high and sustainable OER activity. In situ synchrotron characterizations reveal that the TS-Ir/MnO 2 can trigger a continuous localized lattice oxygen-mediated (L-LOM) mechanism. In particular, the L-LOM process could substantially boost the adsorption and transformation of H 2 O molecules over the oxygen vacancies around the tensile-strained Ir sites and prevent further loss of lattice oxygen atoms in the inner MnO 2 bulk to optimize the structural integrity of the catalyst. Importantly, the resultant PEMWE device fabricated using TS-Ir/MnO 2 delivers a current density of 500 mA cm −2 and operates stably for 200 h. The acidic oxygen evolution reaction plays a crucial role in proton-exchange membrane water electrolysis devices. The authors developed a low-iridium catalyst with tensile-strain able to trigger a localized lattice oxygen-mediated mechanism to realize efficient and stable acid-OER performance.

The oxygen reduction reaction (ORR) catalyzed by efficient and economical catalysts is critical for sustainable energy devices. Although the newly-emerging atomically dispersed platinum catalysts are highly attractive for maximizing atomic utilization, their catalytic selectivity and durability are severely limited by the inflexible valence transformation between Pt and supports. Here, we present a structure by anchoring Pt atoms onto valence-adjustable CuO x /Cu hybrid nanoparticle supports (Pt 1 -CuO x /Cu), in which the high-valence Cu (+2) in CuO x combined with zero-valent Cu (0) serves as a wide-range valence electron reservoir (0‒2e) to dynamically adjust the Pt 5 d valence states during the ORR. In situ spectroscopic characterizations demonstrate that the dynamic evolution of the Pt 5 d valence electron configurations could optimize the adsorption strength of *OOH intermediate and further accelerate the dissociation of O = O bonds for the four-electron ORR. As a result, the Pt 1 -CuO x /Cu catalysts deliver superior ORR performance with a significantly enhanced four-electron selectivity of over 97% and long-term durability. The electrochemical oxygen reduction reaction catalyzed by efficient and economical catalysts is critically important for sustainable energy devices. Here the authors report anchoring Pt atoms onto valence-adjustable CuO x /Cu hybrid nanoparticle to dynamically tune the Pt 5 d valence states at the initial reaction stage for optimizing oxygen reduction performance.

For end-stage liver disease in children, living donor liver transplantation (LDLT) is often the important standard curative treatment. However, there is a lack of research on early recovery of graft function after pediatric LDLT. This is a single-center, ambispective cohort study. We collected the demographic and clinicopathological data of donors and recipients, and determined the risk factors of postoperative delayed recovery of hepatic function (DRHF) by univariate and multivariate Logistic analyses. 181 cases were included in the retrospective cohort and 50 cases in the prospective cohort. The incidence of DRHF after LDLT in children was 29.4%, and DRHF could well evaluate the early recovery of graft function after LDLT. Through Logistic analyses and AIC score, preoperative liver function of donors, ischemia duration level of the liver graft, Ln (Cr of recipients before operation) and Ln (TB of recipients on the 3rd day after operation) were predictive indicators for DRHF after LDLT in children. Using the above factors, we constructed a predictive model to evaluate the incidence of postoperative DRHF. Self-verification and prospective internal verification showed that this prediction model had good accuracy and clinical applicability. In conclusion, we pointed many risk factors for early delayed recovery of graft function after LDLT in children, and developed a visual and personalized predictive model for them, offering valuable insights for clinical management.

Background BcGs1, a cell wall-degrading enzyme (CWDE), was originally derived from Botrytis cinerea . Our previous study revealed that BcGs1 could trigger defense responses and protect plants against various pathogens. We researched the defense response mechanism underlying this BcGs1 elicitation in tomato. Results We revealed that the two domains were required for BcGs1’s full necrosis activity. According to analysis and quantitative real-time PCR of the up-regulated proteins and genes filtered by iTRAQ-based quantitative proteome approach, oxidative metabolism and phenylpropanoid metabolism were speculated to be involved in BcGs1-triggered defense response in tomato. Furthermore, experimental evidence showed that BcGs1 triggered reactive oxygen species (ROS) burst and increased the level of phenylalanine-ammonia lyase (PAL) and peroxidase (POD) enzyme activity, as well as lignin accumulation. Moreover, histochemical analysis revealed that infiltration of BcGs1 in tomato leaves exhibited cell wall thickening compared with untreated plants. Conclusions The results suggested that BcGs1 activated the basal defense response included lignin metabolism contributed to BcGs1-induced resistance to Botrytis. cinerea infection in tomato.

Monitoring the surface dynamics of catalysts under working conditions is important for a deep understanding of the underlying electrochemical mechanisms towards efficient energy conversion and storage. Fourier transform infrared (FTIR) spectroscopy with high surface sensitivity has been considered as a powerful tool for detecting surface adsorbates, but it faces a great challenge when being adopted in surface dynamics investigations during electrocatalysis due to the complication and influence of aqueous environments. This work reports a well designed FTIR cell with tunable micrometre‐scale water film over the surface of working electrodes and dual electrolyte/gas channels for in situ synchrotron FTIR tests. By coupling with a facile single‐reflection infrared mode, a general in situ synchrotron radiation FTIR (SR‐FTIR) spectroscopic method is developed for tracking the surface dynamics of catalysts during the electrocatalytic process. As an example, in situ formed key *OOH is clearly observed on the surface of commercial benchmark IrO2 catalysts during the electrochemical oxygen evolution process based on the developed in situ SR‐FTIR spectroscopic method, which demonstrates its universality and feasibility in surface dynamics studies of electrocatalysts under working conditions. A novel bifunctional in situ Fourier transform infrared (FTIR) cell has been elaborately designed and prepared. By coupling with single‐reflection infrared mode, a facile and general in situ synchrotron FTIR spectroscopic method has been developed based on the FTIR cell for surface dynamic studies of electrodes during electrolysis.

The age-dependent decline in remyelination potential of the central nervous system during ageing is associated with a declined differentiation capacity of oligodendrocyte progenitor cells (OPCs). The molecular players that can enhance OPC differentiation or rejuvenate OPCs are unclear. Here we show that, in mouse OPCs, nuclear entry of SIRT2 is impaired and NAD + levels are reduced during ageing. When we supplement β-nicotinamide mononucleotide (β-NMN), an NAD + precursor, nuclear entry of SIRT2 in OPCs, OPC differentiation, and remyelination were rescued in aged animals. We show that the effects on myelination are mediated via the NAD + -SIRT2-H3K18Ac-ID4 axis, and SIRT2 is required for rejuvenating OPCs. Our results show that SIRT2 and NAD + levels rescue the aged OPC differentiation potential to levels comparable to young age, providing potential targets to enhance remyelination during ageing. Age-dependent decline in remyelination in the CNS is associated with declined differentiation capacity of oligodendrocyte progenitor cells (OPCs). Here, the authors show nuclear entry of SIRT2 is impaired and NAD+ levels are reduced during ageing in mouse OPCs. β-nicotinamide mononucleotide (β-NMN) supplement delays myelin aging and enhances remyelination in the aged mice.

The development of non-iridium-based oxygen evolution reaction (OER) catalysts is crucial for proton exchange membrane water electrolysis (PEMWE), but hydrogen production remains a great challenge because of sluggish OER kinetics and severe catalyst dissolution. Here, we present a 4 f -induced covalent polarity modulation strategy for the construction of 4 f -orbital-modified RuO 2 (4 f -RuO 2 ) nanocatalysts with tunable Ru–O polarity. We find that the OER activity of 4 f -RuO 2 shows a volcano shape as a function of the polarity of Ru–O bond. Consequently, the best 4 f -Nd-RuO 2 catalyst possesses an ultra-low overpotential of 214 mV at 10 mA cm −2 and robust electrochemical stability in 0.1 M HClO 4 . Theoretical calculations coupled with in situ synchrotron infrared and X-ray absorption spectroscopy analyses reveal that the modulation of Ru–O polarity in RuO 2 by the valence f − p − d gradient orbital coupling can modify the adsorption energy of the reaction intermediates and suppress the participation of lattice oxygen to avoid over-oxidation of Ru, which can thus serve as an effective descriptor for fine tuning the activity and durability of acidic OER nanocatalysts. The sluggish oxygen evolution reaction kinetics and intense catalyst degradation under acidic conditions limit the practical application of electrolyzers. Here, the authors construct 4 f -orbital-modified RuO 2 catalysts with tunable Ru–O polarity that enhance catalytic activity and durability.

The high specific capacity of transition metal sulfides (TMSs) opens up a promising new development direction for lithium-ion batteries with high energy storage. However, the poor conductivity and serious volume expansion during charge and discharge hinder their further development. In this work, trimetallic sulfide Zn–Co–Fe–S@nitrogen-doped carbon (Zn–Co–Fe–S@N–C) polyhedron composite with a core–shell structure is synthesized through a simple self-template method using ZnCoFe–ZIF as precursor, followed by a dopamine surface polymerization process and sulfidation during high-temperature calcination. The obvious space between the internal core and the external shell of the Zn–Co–Fe–S@N–C composites can effectively alleviate the volume expansion and shorten the diffusion path of Li ions during charge and discharge cycles. The nitrogen-doped carbon shell not only significantly improves the electrical conductivity of the material, but also strengthens the structural stability of the material. The synergistic effect between polymetallic sulfides improves the electrochemical reactivity. When used as an anode in lithium-ion batteries (LIBs), the prepared Zn–Co–Fe–S@N–C composite exhibits a high specific capacity retention (966.6 mA h g−1 after 100 cycles at current rate of 100 mA g−1) and good cyclic stability (499.17 mA h g−1 after 120 cycles at current rate of 2000 mA g−1).