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The annual regrowth of deer antlers provides a valuable model for studying organ regeneration in mammals. We describe a single-cell atlas of antler regrowth. The earliest-stage antler initiators were mesenchymal cells that express the paired related homeobox 1 gene ( PRRX1 + mesenchymal cells). We also identified a population of “antler blastema progenitor cells” (ABPCs) that developed from the PRRX1 + mesenchymal cells and directed the antler regeneration process. Cross-species comparisons identified ABPCs in several mammalian blastema. In vivo and in vitro ABPCs displayed strong self-renewal ability and could generate osteochondral lineage cells. Last, we observed a spatially well-structured pattern of cellular and gene expression in antler growth center during the peak growth stage, revealing the cellular mechanisms involved in rapid antler elongation.

Selective semi-hydrogenation of phenylacetylene to styrene is a crucial step in the polystyrene industry. Although Pd-based catalysts are widely used in this reaction due to their excellent hydrogenation activity, the selectivity for styrene remains a great challenge. Herein, we designed a mesoporous silica stabilized Pd-Ru@ZIF-8 (MS Pd-Ru@ZIF-8) nanoreactor with novel Pd and Ru single site synergistic catalytical system for semi-hydrogenation of phenylacetylene. The nanoreactor exhibited a superior performance, achieving 98% conversion of phenylacetylene and 96% selectivity to styrene. Turnover frequency (TOF) of nanoreactor was up to as high as 2,188 h⁻¹, which was 25 times and 5 times more than the single metal species catalysts, mesoporous silica stabilized Pd@ZIF-8 nanoreactor (MS Pd@ZIF-8), and mesoporous silica stabilized Ru@ZIF-8 nanoreactor (MS Ru@ZIF-8). This catalytic activity was attributed to the synergistic effect of Pd and Ru single site anchored strongly into the framework of ZIF-8, which reduced the desorption energy of styrene and increased the hydrogenation energy barrier of styrene. Importantly, since the ordered mesoporous silica was introduced into the nanoreactor shell to stabilize ZIF-8, MS Pd-Ru@ZIF-8 showed excellent reusability and stability. After the five cycles, the catalytical activity and selectivity still remained. This work provides insights for a synergistic catalytic system based on single-site active sites for selective hydrogenation reactions.

Arterial calcification is an important risk factor for patients with end-stage renal disease. Despite substantial research efforts, the detailed mechanisms of the process of arterial calcification in end-stage renal disease remain unclear. miR-133a expression in radial artery samples was detected by FISH and Alizarin Red Staining. The expressions of miR-133a and RUNX2 in A7r5 cells with BMP2 induction were detected by qRT-PCR. In addition, qRT-PCR, Western blot, and ELISA assay were performed to detect changes in miR-133a levels in A7R5 cells after different treatments. Alizarin Red staining showed that red crystal deposition occurred in the tunica media. FISH analysis indicated that miR-133a was upregulated in the tunica media of the radial artery samples without calcification when compared with those with calcification. We also found that expression of RUNX2 in A7r5 cells increased at day 7 and day 14 after BMP2 induction and decreased miR-133a expression decreased at day 14. In addition, RUNX2 protein and OCN expression were upregulated in A7r5 cells during BMP2-induced calcification. When miR-133a expression was suppressed, cell calcification aggravated, which led to upregulation of RUNX2 and OCN. When miR-133a was overexpressed, calcification of cells was inhibited, resulting in downregulation of RUNX2 and OCN. The present study reveals that miR-133a could indirectly regulate cell calcification through the RUNX2 gene expression. Our findings provide insight into the potential use of miR-133a as a molecular target for diagnosing vascular calcification in end-stage renal disease.

MRSA is a super drug-resistant bacterium. Developing new drug or therapeutic strategies against MRSA is urgently needed. Increasing evidence has shown that herbal extracts and antibiotics can have synergistic effects against MRSA. This review focuses on commonly used antibiotics combined with herbal extracts against MRSA and the corresponding mechanisms. Through systematic analysis, we found that herbal extracts combined with antibiotics, such as β-lactams, quinolones, aminoglycosides, tetracyclines and glycopeptides, could greatly enhance the antibacterial effects of the antibiotics, reduce the dosage and toxic side effects, and reverse MRSA resistance. Therefore, we conclude that herbal extracts combined with antibiotics may be a promising strategy to combat MRSA. This review provides a novel idea for overcoming antibiotic resistance.

Carbon-carbon (C-C) coupling reactions represent one of the most powerful tools for the synthesis of complex natural products, bioactive molecules developed as drugs and agrochemicals. In this work, a multifunctional nanoreactor for C-C coupling reaction was successfully fabricated via encapsulating the core-shell Cu@Ni nanocubes into ZIF-8 (Cu@Ni@ZIF-8). In this nanoreactor, Ni shell of the core-shell Cu@Ni nanocubes was the catalytical active center, and Cu core was in situ heating source for the catalyst by absorbing the visible light. Moreover, benefiting from the plasmonic resonance effect between Cu@Ni nanocubes encapsulated in ZIF-8, the absorption range of nanoreactor was widened and the utilization rate of visible light was enhanced. Most importantly, the microporous structure of ZIF-8 provided shape-selective of reactant. This composite was used for the highly shape-selective and stable photocatalysed C-C coupling reaction of boric acid under visible light irradiation. After five cycles, the nanoreactor still remained high catalytical activity. This Cu@Ni@ZIF-8 nanoreactor opens a way for photocatalytic C-C coupling reactions with shape-selectivity.

Highly ordered hierarchical macroporous metal–organic framework (MOF) materials (macroporous MIL-125) have been successfully synthesized through a solvent evaporation-induced self-assembly route in...

Li Wang,1 Sha Li,1 Yihao Mo,1 Mingliang Hu,1 Junwei Zhang,1 Min Zeng,1 Huafeng Li,1 Honglei Zhao2 1Department of Nephrology, People’s Hospital of Longhua District, Shenzhen, Guangdong, People’s Republic of China; 2Department of Cardiology, Fuwai Hospital Chinese Academy of Medical Science, Shenzhen, Guangdong, People’s Republic of ChinaCorrespondence: Honglei Zhao, Tel + 86-755-23650123, Email zhldoctor@tom.comPurpose: The current study was to evaluate the gender-disparities in the in-hospital thrombotic and bleeding events among patients with chronic kidney disease (CKD) undergoing percutaneous coronary intervention (PCI).Patients and Methods: Patients with CKD undergoing PCI were retrospectively enrolled. Baseline characteristics, and thrombotic and bleeding events occurred during hospitalization were collected and compared by gender.Results: Compared to males (n = 558), females (n = 402) were older and more likely to have diabetes mellitus (37.1% vs 29.7%). Females had a lower estimated glomerular filtration rate (eGFR; 51.2 ± 7.9 vs 54.6 ± 5.1 mL/min/1.73m2) and were more likely to undergo urgent PCI (66.7% vs 60.2%) and use glycoprotein IIb/IIIa inhibitor (15.4% vs 7.5%) at peri-PCI period. Compared to males, females had a higher rate of in-hospital mortality which was due to thrombotic events (9.0% vs 3.4%). Females also had a higher rate of moderate-to-severe hemorrhage (8.0% vs 3.2%). After multivariable adjustment, diabetes mellitus (odds ratio [OR] 1.15 and 95% confidence interval [CI] 1.07–1.29) and acute coronary syndrome (ACS) presentation (OR 1.53 and 95% CI 1.34–1.93) were associated with gender-disparities in composite thrombotic events. Ageing (OR 1.10 and 95% CI 1.02–1.33), diabetes mellitus (OR 1.21 and 95% CI 1.07–1.40) and glycoprotein IIb/IIIa inhibitor use (OR 1.13 and 95% CI 1.02–1.28) were associated with composite bleeding events.Conclusion: Females with CKD undergoing PCI had a higher risk of experiencing in-hospital thrombotic and bleeding events than males.Keywords: coronary heart disease, chronic kidney disease, prognosis, gender

The analog data acquisition system developed in this paper is integrated into the remote interface unit of aircraft. It uses the high certainty and high real-time performance of the IEEE-1394B bus to realize information interaction with the aircraft backbone network, and participates in sensor closed-loop regulation and state information feedback. Using DSP + FPGA architecture, the functions of bus communication, high-speed data acquisition and decoupling control are realized. The normalization design of analog data acquisition is realized by using table driving and dynamic switching technology. The method of error calibration is applied to realize high-precision acquisition. The system software is divided into acquisition layer, interpretation layer and application layer, which has strong portability. The experimental results show that the acquisition accuracy is high, which can meet the requirements of aircraft analog data acquisition. The system developed has the characteristics of high real-time, generalization, miniaturization and strong data processing ability.

The electronic-mechanical actuator servo control system designed in this paper is integrated in the aircraft remote execution unit. It uses the IEEE-1394B bus to realize the information interaction with the aircraft backbone network, and uses the basic topological with ring to realize the fault tolerance of a disconnection. Through pre-distribution broadband technology, the deterministic transmission of control commands is realized. The system adopts DSP+FPGA architecture to realize the decoupling control between bus communication, algorithm control, motor protection and BIT logic operation. The DRV8301 driver is used to realize power conversion and three-phase power bridge drive with overcurrent, undervoltage, overvoltage, overheating and other protection functions. By configuring the Hall sensor and quadrature encoder at the same time, it can realize the margin acquisition of the rotor position. The experimental results show that the system designed in this paper is simple, reliable, and time-deterministic, it can be widely used in the flow, pressure and temperature adjustment of the network nodes in each area of the aircraft.

Growing greenhouse gas CO2 is driving the research on the chemical fixation of CO2. Here, the organic reaction of CO2 with benzyl halogen for chemical CO2 fixation under ambient conditions with irr...

A chromosome-level giraffe genome assembly and gene-edited mice reveal molecular mechanisms underpinning its high stature., The suite of adaptations associated with the extreme stature of the giraffe has long interested biologists and physiologists. By generating a high-quality chromosome-level giraffe genome and a comprehensive comparison with other ruminant genomes, we identified a robust catalog of giraffe-specific mutations. These are primarily related to cardiovascular, bone growth, vision, hearing, and circadian functions. Among them, the giraffe FGFRL1 gene is an outlier with seven unique amino acid substitutions not found in any other ruminant. Gene-edited mice with the giraffe-type FGFRL1 show exceptional hypertension resistance and higher bone mineral density, both of which are tightly connected with giraffe adaptations to high stature. Our results facilitate a deeper understanding of the molecular mechanism underpinning distinct giraffe traits, and may provide insights into the study of hypertension in humans.

Endothermy is a typical convergent phenomenon which has evolved independently at least eight times in vertebrates, and is of significant advantage to organisms in extending their niches. However, how vertebrates other than mammals or birds, especially teleosts, achieve endothermy has not previously been fully understood. In this study, we sequenced the genomes of two billfishes (swordfish and sailfish), members of a representative lineage of endothermic teleosts. Convergent amino acid replacements were observed in proteins related to heat production and the visual system in two endothermic teleost lineages, billfishes and tunas. The billfish-specific genetic innovations were found to be associated with heat exchange, thermoregulation, and the specialized morphology, including elongated bill, enlarged dorsal fin in sailfish and loss of the pelvic fin in swordfish.

The electrochemical splitting of water into hydrogen and oxygen is considered one of the most promising approaches to generate clean and sustainable energy. However, the low efficiency of the oxygen evolution reaction (OER) acts as a bottleneck in the water splitting process. Herein, interface engineering heterojunctions between ZIF‐67 and layered double hydroxide (LDH) are designed to enhance the catalytic activity of the OER and the stability of Co‐LDH. The interface is built by the oxygen (O) of Co‐LDH and nitrogen (N) of the 2‐methylimidazole ligand in ZIF‐67, which modulates the local electronic structure of the catalytic active site. Density functional theory calculations demonstrate that the interfacial interaction can enhance the strength of the Co—Oout bond in Co‐LDH, which makes it easier to break the H‐Oout bond and results in a lower free energy change in the potential‐determining step at the heterointerface in the OER process. Therefore, the Co‐LDH@ZIF‐67 exhibits superior OER activity with a low overpotential of 187 mV at a current density of 10 mA cm−2 and long‐term electrochemical stability for more than 50 h. This finding provides a design direction for improving the catalytic activity of OER., The interface of Co‐LDH@ZIF‐67 is built by the oxygen of cobalt layered double hydroxide (Co‐LDH) and nitrogen of the ZIF‐67, which can modulate the electronic structure of the catalytical site. The Co‐LDH@ZIF‐67 exhibits superior catalytical activity in oxygen evolution reaction with a low overpotential of 187 mV at a current density of 10 mA cm−2.

The hexagonal copper-tin alloy (Cu-Sn) nanoplates were synthesized using a high temperature solvent method, the length of six equilateral edges of hexagonal Cu-Sn nanoplates was 23 nm, and the thickness was 13 nm. The obtained hexagonal Cu-Sn nanoplates were highly monodisperse and allowed the formation of nanoarrays arranged with long-range order. The hexagonal Cu-Sn nanoplates exhibited high catalytic activity on catalytic hydrogenation of 4-nitrophenol to 4-aminophenol. Due to the promotion effect of Sn, the apparent rate constant (

The fiber-optic external sinusoidal phase-modulating interferometer (ESPMI) is sensitive, accurate, and robust. However, parasitic interference hinders further improvement of its precision, and reduces its adaptability to measurement targets with different characteristics. In this paper, we analyzed the mathematical model of parasitic interference, and proposed a Kalman filter-based method to eliminate the parasitic interference effect in the ESPMI. This method works by filtering out the time-varying offsets in quadrature signals brought by the parasitic interference. Simulations and experiments were conducted to verify the effectiveness of the proposal. The experimental results showed that our proposal had great parasitic interference effect elimination ability. Compared with existing schemes, our method is highly accurate and low-cost with no loss in interferometric range, thus having catalytic effect on the application of ESPMI in related fields.

With the development of multi-/all-electric technology, more and more aircraft platforms use electrically driven servo valves as the driving source to realize real-time adjustments of flow, pressure and temperature in the area network. The new generation of aircraft applies a stepper motor to drive the servo valve as the drive source, and utilizes the holding torque and open-loop control characteristics of the stepper motor when the stepper motor could not meet aircraft’s requirements of the reliability of the servo valve, the controllability of the opening and closing angle, and the environmental resistance. This paper develops a set of stepper motor drive servo valve control system. The system is mainly composed of flight tube bus, electromechanical management computer, remote actuation unit, remote interface unit and motor-driven servo valve. The stepper motor driver is integrated in the remote execution unit and is used to control the two-phase hybrid stepper motor to drive the servo valve. The topology of a three-phase inverter bridge drive is used to achieve the two-phase double four-shot drive, which saves about 25% power drive hardware. By controlling the two-phases motor, the direction and amplitude of the current one can realize micro-step control. The test and simulation result show that the system has higher control accuracy and better acceleration. The deceleration characteristics in two-phase full step and micro step working modes can expand the application of electric servo valve and improve aircraft performance.

The integrated thermal management of advanced fighter jets directly affects the combat performance of the aircraft. This paper develops a set of multi-cycle integrated thermal management control system, based on the stepper motor drive servo valve. The stepper motor control system is integrated in the aircraft Remote Execution Unit (REU). The controlled information, such as flow, pressure, temperature, is collected and combined through the Remote Interface Unit (RIU). Through the IEEE-1394 bus, feedback achieves deterministic transmission between control-action-response, and through inverse time protection, the high reliable power drive can be achieved. The open-loop vector micro-stepping driving strategy of the stepper motor is designed, simplifying software and hardware designs. The experimental results show that the strategy developed in this paper can better realize the characteristics of two-phase current sine wave, have better acceleration performance, improve the controllability of the opening and closing angle of the stepping motor servo valve, and satisfy the comprehensive thermal management of advanced fighters.

The eigenmodes based on paraxial accelerating beams in nonlinear atomic vapors with Kerr and cubic-quintic nonlinearities are demonstrated from mathematical models and numerical simulations. Upon adjusting the generation and propagation conditions, these nonlinear accelerating beams exhibit different evolution properties. We show numerically that the adopted beams can propagate robustly in the medium regardless of its absorption properties. The shape and peak intensity of the main lobes of these beams, based on the fact that they are the eigenmodes of the nonlinear Schrodinger equation in atomic media, are preserved for a significantly long propagation distance. If such beams are not the modes of the system, they are subject to the under-healing or over-healing effect, which damages the shape of the self-accelerating beams. In a numerical investigation, we also discuss the interactions between truncated accelerating beams, which readily generate non-accelerating solitons and soliton pairs.

In a water electrolysis system, the cathode and anode produce H2 and O2 with HER and OER, respectively. The energy conversion efficiency of the electrolysis systems is about 56–73% in practical application, and the low energy conversion efficiency greatly limits the large-scale application. Hence, the electrocatalytic water splitting has attracted much attention. Recently, a variety of heterogeneous catalysts have emerged, showing high catalytic water splitting performance. Among them, the heterojunction catalysts occupied a very important position in emerging catalysts. In the heterojunction catalysts, electrons can be rearranged on heterostructures interfaces to modify the properties of active sites, and synergy of different active sites is used to promote the reaction kinetics. The heterojunction catalysts often show a better activity of electrolysis water than single-component catalysts. Herein, we mainly summarize the design strategies and synthesis methods of various heterojunction catalysts and the related applications of these heterojunction catalysts in HER and OER, and further discusses the catalytical mechanisms in HER and OER processes respectively. Through the summary of present progress in electrocatalytic water splitting, this review provides a reasonable prospect on heterojunction catalysts in electrocatalytic water splitting.

The metal halide with a perovskite structure has attracted significant attention due to its defect-tolerant photophysics and optoelectronic features. In particular, the all-inorganic metal halide perovskite quantum dots have potential for development in future applications. Sub-2 nm CsPbX3 (X = Cl, Br, and I) perovskite quantum dots were successfully fabricated by a MOF-confined strategy with a facile and simple route. The highly uniform microporous structure of MOF effectively restricted the CsPbX3 quantum dots aggregation in a synthetic process and endowed the obtained sub-2 nm CsPbX3 quantum dots with well-dispersed and excellent stability in ambient air without a capping agent. The photoluminescence emission spectra and lifetimes were not decayed after 60 days. The CsPbX3 quantum dots maintained size distribution stability in the air without any treatment. Because of the quantum confinement effect of CsPbX3 quantum dots, the absorption and photoluminescence (PL) emission peak were blue shifted to shorter wavelengths compare with bulk materials. Furthermore, this synthetic strategy provides a novel method in fabricating ultra-small photoluminescence quantum dots.

Three and four electromagnetically induced transparency windows generate the multi-channel four-wave mixing (FWM) process are observed in a four-level atomic system. The transmission of the probe field and the reflection of the FWM are investigated in the modulated moving photonic band gap structures which are caused by the coupling fields with a relative small detuning offset when scanning detuning frequency of the probe field and the dressing field, respectively. The experimental results show that the more channels spectrum signal of the FWM process can be modulated and the generated multi-channel can be further modulated by adding a dressing field. We have also explained theoretically these experimental results which may have applications in the design of photonic crystal and optical signal amplifiers.

Eight-wave mixing (EWM) is a seven-order nonlinear process that can reflect nonclassical features within multiple optical fields, thus imparting certain advantages. In this study, we directly observed the EWM spectrum and spatial images that show Rydberg atoms under a circularly polarized probe field in a five-level coherently prepared atomic system. Such circular polarization dressing fields can obtain high-contrast Rydberg EWM overcome the difficulties of several multi-wave mixing (MWM) signals always coexist, and the multi-parameter controlling Rydberg EWM mechanism is established by changing the power and detuning and polarization of the dressing fields. These controllable high-order MWM processes present a contrast ratio of 96% and a narrow linewidth of