Objective This prospective single-arm clinical trial aimed to evaluated the feasibility and safety of the application of the SHURUI system(Beijing Surgerii Technology Co.,Ltd.,Beijing,China),a novel purpose-built robo...Objective This prospective single-arm clinical trial aimed to evaluated the feasibility and safety of the application of the SHURUI system(Beijing Surgerii Technology Co.,Ltd.,Beijing,China),a novel purpose-built robotic system,in single-port robotic radical prostatectomy.Methods Sixteen patients diagnosed with prostate cancer were prospectively enrolled in and underwent robotic radical prostatectomy from October 2021 to August 2022 by the SHURUI single-port robotic surgical system.The demographic and baseline data,surgical,oncological,and functional outcomes as well as follow-up data were recorded.Results The mean operative time was 226.3(standard deviation[SD]52.0)min,and the mean console time was 183.4(SD 48.3)min,with the mean estimated blood loss of 116.3(SD 90.0)mL.The mean length of postoperative hospital stay was 4.50(SD 0.97)days.Two patients had postoperative complications(Clavien-Dindo Grade II),and both patients improved after conservative treatment.All patients’postoperative prostate-specific antigen levels decreased to below 0.2 ng/mL 1 month after discharge.The mean prostate-specific antigen level further decreased to a mean of 0.0219(SD 0.0641)ng/mL 6 months after surgery.Thirty days postoperatively,12 out of 16 patients reported using no more than one urinary pad per day,and all patients reported satisfactory urinary control without the need for pads 6 months after surgery.Conclusion The SHURUI system is safe and feasible in performing radical prostatectomy via both transperitoneal and extraperitoneal approaches.Tumor control and urinary continence were satisfying for patients enrolled in.The next phase involves conducting a large-scale,multicenter randomized controlled trial to thoroughly assess the effectiveness and safety of the new technology in a broader population.展开更多
The ravages of COVID-19 have forced schools in countries around the world to make a temporary shift from traditional, face-to-face teaching to online teaching. Are teachers in schools prepared to deal with this change...The ravages of COVID-19 have forced schools in countries around the world to make a temporary shift from traditional, face-to-face teaching to online teaching. Are teachers in schools prepared to deal with this change? We conducted a survey in which we distributed questionnaires to primary and secondary school teachers in Guangdong Province, China, asking them about their views on various aspects of online education. We received 498,481 questionnaires back, and over 80% of teachers were satisfied with the online resources, and over 68% of teachers were satisfied with the online platform and software. Immediately afterward, we analyzed the differences between urban and rural teachers on specific issues using cross-sectional analysis and chi-square tests and built a neural network model to achieve predictions of teacher satisfaction with an accuracy of nearly 90%. Finally, we analyzed the features that influence the decisions of the neural network. This epidemic has prompted the widespread use of online learning, and the insights we gain today will be helpful in the future.展开更多
Unlike the reported leaching technologies of waste superalloys, the process of the “atomized spray-sulfuric acid leaching nickel and cobalt” technology was put forward in the present work according to the compositio...Unlike the reported leaching technologies of waste superalloys, the process of the “atomized spray-sulfuric acid leaching nickel and cobalt” technology was put forward in the present work according to the compositions of waste superalloys. The effects of sulfuric acid temperature, concentration, leaching time, stirring speed and size of superalloys on leaching of Ni and Co from waste superalloys have been mainly investigated, and the optimum leaching conditions were determined and reported. The leaching rates for nickel and cobalt were 96.68% and 96.63%, respectively, and the contents of nickel and cobalt in leaching slag were 6.77% and 0.96%, respectively. The obtained leaching solution containing Ni and Co could be used for production of Ni and Co products after removal.展开更多
The electrocatalytic activity of transition-metal-based compounds is closely related to the electronic configuration.However,optimizing the surface electron spin state of catalysts remains a challenge.Here,we develope...The electrocatalytic activity of transition-metal-based compounds is closely related to the electronic configuration.However,optimizing the surface electron spin state of catalysts remains a challenge.Here,we developed a spin-state and delocalized electron regulation method to optimize oxygen evolution reaction(OER)performance by in-situ growth of NiCo_(2)(OH)_(x) using Oswald ripening and coordinating etching process on MXene and plasma treatment.X-ray absorption spectroscopy,magnetic tests and electron paramagnetic resonance reveal that the coupling of NiCo_(2)(OH)_(x) and MXene can induce remarkable spin-state transition of Co^(3+)and transition metal ions electron delocalization,plasma treatment further optimizes the 3 d orbital structure and delocalized electron density.The unique Jahn-Teller phenomenon can be brought by the intermediate spin state(t2 _(g)^(5) e_(g)^(1))of Co^(3+),which benefits from the partial electron occupied egorbitals.This distinct electron configuration(t2_(g)^(5) e_(g)^(1))with unpaired electrons leads to orbital degeneracy,that the adsorption free energy of intermediate species and conductivity were further optimized.The optimized electrocatalyst exhibits excellent OER activity with an overpotential of 268 m V at 10 m A cm^(-2).DFT calculations show that plasma treatment can effectively regulate the d-band center of TMs to optimize the adsorption and improve the OER activity.This approach could guide the rational design and discovery of electrocatalysts with ideal electron configurations in the future.展开更多
Objective:Prostate cancer is a form of cancer that develops in the prostate,a gland in the male reproductive system.Prostate cancer tends to develop in men over the age of fifty;it is one of the most prevalent types o...Objective:Prostate cancer is a form of cancer that develops in the prostate,a gland in the male reproductive system.Prostate cancer tends to develop in men over the age of fifty;it is one of the most prevalent types of cancer in men.This article introduced a new method of prostate cancer treatment with the combination of three dimensional conformal radiation therapy (3D-CRT) and high-intensity focused ultrasound (HIFU),its efficacy was evaluated.Methods:From January 2004 to December 2009,95 patients were diagnosed with prostate cancer,among them,48 patients were received combined therapy with total irradiation of TD 60 Gy/30 Fx and 5 fractions of HIFU treatment,while 47 patients were received with pure 3D-CRT with total irradiation of TD (66-72) Gy/(33-36) Fx.Various indicators were evaluated,such as the local control rate and distant metastasis rate,the changes in blood PSA and fPSA,changes in T-lymphocyte subsets and NK cells,as well as acute adverse reaction of normal tissue.Results:The local response rate difference between the two groups had statistical significance (P < 0.05);the changes in blood PSA and fPSA were significant (P < 0.05);CD3+,CD4+,CD8+,CD4+/CD8+ and NK cells of the combined group increased obviously (P < 0.01),while the latter group had no increase (P > 0.05);the combined group had lower blood cells reduction and II-level acute adverse reaction of rectum,bladder and caput humeri than the pure group,but the II-level acute adverse reaction of urogenital canal in the combined group was higher (P < 0.05).Conclusion:The combined therapy with 3D-CRT and HIFU is a good way for the treatment of aged-related prostate cancer.It can ease the symptoms,control the disease and lengthen the survival time.展开更多
The current cultivation of apple trees mainly relies on grafted seedlings to achieve seedling regeneration of apple trees. The commonly used splice grafting,V-shaped grafting and tongue grafting mostly use plastic fil...The current cultivation of apple trees mainly relies on grafted seedlings to achieve seedling regeneration of apple trees. The commonly used splice grafting,V-shaped grafting and tongue grafting mostly use plastic film for fixation and sealing. After one year,the wrapped plastic film needs to be removed to avoid affecting the growth of the seedlings. This paper introduces a brand new grafting technology which uses tongue grafting iron nails for fixation and growth fixation wax for sealing( SDRG). The process of mechanized grafting for apple nursery stock is determined,and the fixation and sealing problems with the grafting parts of seedlings are solved. The technology is characterized by quick speed,high efficiency,improved seedling survival rate lower labor cost and great significance to the promotion of industrialized nursery and mechanized grafting.展开更多
Recently,mega Low Earth Orbit(LEO)Satellite Network(LSN)systems have gained more and more attention due to low latency,broadband communications and global coverage for ground users.One of the primary challenges for LS...Recently,mega Low Earth Orbit(LEO)Satellite Network(LSN)systems have gained more and more attention due to low latency,broadband communications and global coverage for ground users.One of the primary challenges for LSN systems with inter-satellite links is the routing strategy calculation and maintenance,due to LSN constellation scale and dynamic network topology feature.In order to seek an efficient routing strategy,a Q-learning-based dynamic distributed Routing scheme for LSNs(QRLSN)is proposed in this paper.To achieve low end-toend delay and low network traffic overhead load in LSNs,QRLSN adopts a multi-objective optimization method to find the optimal next hop for forwarding data packets.Experimental results demonstrate that the proposed scheme can effectively discover the initial routing strategy and provide long-term Quality of Service(QoS)optimization during the routing maintenance process.In addition,comparison results demonstrate that QRLSN is superior to the virtual-topology-based shortest path routing algorithm.展开更多
Hematite(α-Fe_(2)O_(3))is an ideal oxide semiconductor candidate for photoelectrochemical(PEC)water splitting.Doping of Fe_(2)O_(3)is known to benefit the PEC water oxidation efficiency,but despite extensive research...Hematite(α-Fe_(2)O_(3))is an ideal oxide semiconductor candidate for photoelectrochemical(PEC)water splitting.Doping of Fe_(2)O_(3)is known to benefit the PEC water oxidation efficiency,but despite extensive research efforts,the underlying mechanism still remains elusive.In this work,we report a comprehensive study on the relationship between the electronic structure,interfacial reaction kinetics and PEC activity of Ti-doped Fe_(2)O_(3)photoanodes.The results show that the interfacial charge transfer efficiency at the Fe_(2)O_(3)/electrolyte interface is the main factor in the significant increase of the PEC activity of doped Fe_(2)O_(3).Electrochemical impedance spectroscopy reveals that the interfacial charge transfer efficiency is determined by energy overlap between the water oxidation potential and energy distribution of an intermediate surface state that has been identified as Fe^(IV)=O groups on Fe_(2)O_(3)surface generated during PEC process.Interestingly,the potential energy distribution of this intermediate surface state can be modulated by Ti doping,and a shift towards a more positive potential of the intermediate surface state increases the overlap with the water oxidation potential and thus enhances the kinetics of charge transfer for PEC water splitting.The origin of such potential energy modulation is traced to the inductive effect from Ti-doping on the Fe^(3+)/Fe^(4+)redox transition and the Fe-O bond covalency.Our results provide new insight into the mechanism for the doping effect on the PEC water splitting,introducing new strategies to optimize the PEC activity by tuning the redox properties of active metal oxides.展开更多
Superlattices in crystals,particularly in perovskite oxides with strong correlation effects,can create new states of matter and produce peculiar physicochemical phenomena.However,the newfangled perovskite superlattice...Superlattices in crystals,particularly in perovskite oxides with strong correlation effects,can create new states of matter and produce peculiar physicochemical phenomena.However,the newfangled perovskite superlattices depend on physical deposition with unit-cell precision.It has been challenging to explore a new suitable chemical method to tailor perovskite superlattices.Herein,we present a new bottomup strategy to precisely prepare atomic-scale oxide superlattices of(LaMnO_(3))_(1)-(La_(1-x-y)Ca_(x)K_(y)MnO_(3))_(2)in a monodispersed perovskite La_(0.66)Ca_(0.29)K_(0.05)MnO_(3)(LCKMO).The special atomic-scale perovskite superlattices are demonstrated using SAED,HAADF-STEM,XRD,and atomic-resolution elemental mapping.Our experiments reveal that the perovskite superlattices can be fabricated under extreme hydrothermal conditions utilizing ultra-high concentrations of KOH.An approximate molten salt system in the hydrothermal process can induce the disproportionation reaction of MnO_(2)solids,which is vital to the growth of ordered perovskite superlattices.This work not only clarifies the hydrothermal growth process of perovskite oxides in extreme conditions,but also proposes a novel engineering route toward perovskite superlattices.展开更多
To the Editor:Chronic thromboembolic pulmonary hypertension(CTEPH)is a chronic progressive disease in which pulmonary artery pressure(PAP)increases and eventually leads to right heart failure and death.Balloon pulmona...To the Editor:Chronic thromboembolic pulmonary hypertension(CTEPH)is a chronic progressive disease in which pulmonary artery pressure(PAP)increases and eventually leads to right heart failure and death.Balloon pulmonary angioplasty(BPA)is a new and effective treatment for CTEPH patients who are unsuitable for surgery or who develop recurrent or persistent pulmonary hypertension after pulmonary endarterectomy(PEA).In recent years,major medical centers at home and abroad have been gradually developing and improving BPA,but overall,a unified treatment process and complication control strategy is lacking.展开更多
The combination of covalent organic framework(COF)photosensitizers with molecular cocatalysts is a promising avenue for photocatalytic carbon dioxide(CO_(2))reduction.Here,a series of isostructural COFs was synthesize...The combination of covalent organic framework(COF)photosensitizers with molecular cocatalysts is a promising avenue for photocatalytic carbon dioxide(CO_(2))reduction.Here,a series of isostructural COFs was synthesized using linkers of different lengths,with or without partial fluorination.These COFs were investigated for photocatalytic CO_(2)reduction under visible-light irradiation when combined with cobalt(II)bipyridine complexes as a cocatalyst.Fluorination was found to enhance both CO_(2)affinity and catalytic activity,and a partially fluorinated COF,FBP-COF,achieved the highest CO_(2)-to-CO conversion efficiency,showing a carbon monoxide(CO)generation rate of 2.08 mmol h−1 g−1 and a 90%CO selectivity.FBP-COF also showed good stability under sacrificial conditions,generating CO for 50 h with a turnover number of 91.5.This activity is much higher than a homogeneous system using ruthenium bipyridine complexes as the photosensitizer combined with the same cobalt bipyridine complexes.展开更多
This study aims to produce an effective subunit vaccine against infectious bursal disease virus (IBDV). The genes of chicken interleukin-2 (ChIL-2) and IBDV viral protein 2 (VP2) were amplified and fused by spli...This study aims to produce an effective subunit vaccine against infectious bursal disease virus (IBDV). The genes of chicken interleukin-2 (ChIL-2) and IBDV viral protein 2 (VP2) were amplified and fused by splice overlap extension-polymerase chain reaction (SOE-PCR). The fusion gene was digested by EcoR I/Kpn I and inserted into pBacPAK8 vector, resulting in recombinant transfer plasmid pBacPakVP2-IL2. The recombinant plasmid was transfected into Sf-9 cells accompanied with hybrid nuclear polyhedrosis virus (HyNPV) genome DNA and lipofectin. Plaque-purification indicated that we had got the recombinant Hy-VP2-IL2. Fusion protein VP2-IL2 was expressed effectively both in insect cells and bombyx mori. The expression of fusion protein was confirmed by ELISA, SDS-PAGE and Western blotting assay, respectively. This efficient system allows us to meet the need for inexpensive vaccines required by the poultry industry. Cellular & Molecular Immunology. 2005;2(3):231-235.展开更多
The design and synthesis of highly active non-noble metal oxide catalysts, such as transition- and rare-earth-metal oxides, have attracted significant attention because of their high efficiency and low cost and the re...The design and synthesis of highly active non-noble metal oxide catalysts, such as transition- and rare-earth-metal oxides, have attracted significant attention because of their high efficiency and low cost and the resultant potential applications for the degradation of volatile organic compounds(VOCs). The structure-activity relationships have been well-studied and used to facilitate design of the structure and composition of highly active catalysts. Recently, non-noble metal oxides with porous structures have been used as catalysts for deep oxidation of VOCs, such as aromatic hydrocarbons, aliphatic compounds, aldehydes, and alcohols, with comparable activities to their noble metal counterparts. This review summarizes the growing literature regarding the use of porous metal oxides for the catalytic removal of VOCs, with emphasis on design of the composition and structure and typical synthetic technologies.展开更多
In this paper, we demonstrated trace of dye molecules in living plants. The NaGdF4:Yb^(3+),Er^(3+) nanoparticles probe was used to detect the rhodamine B(RhB) in bean sprout. It is found that the fluorescencedye can b...In this paper, we demonstrated trace of dye molecules in living plants. The NaGdF4:Yb^(3+),Er^(3+) nanoparticles probe was used to detect the rhodamine B(RhB) in bean sprout. It is found that the fluorescencedye can be efficiently imbibed during the growing process and the absorbance presented a position dependence effect, which was supported by the upconversion spectra and the fluorescent image characterization. In addition, the concentration of the residual RhB in bean sprout can be efficiently traced by the synthesized probe based on the fluorescent resonant energy transfer. Finally, the relation between the excitation power, concentration and the ratio of yellow to green emission are discussed in detail. These results can be helpful in understanding the RhB dye molecules absorbance process in vegetable growth and provide an efficient way to trace the residual dyes in vivo plant.展开更多
基金The authors would like to express their gratitude to Prof.Kai Xu and his research and development team from Shanghai Jiao Tong University,Shanghai,China,for their invaluable technical support of this study.This research was funded by the National Key Research and Development Program of China(Grant No.2022YFB4700904 to Wang L)Research-Oriented Physicians'Innovative Transformation Training Program of Development Center,Shanghai Shenkang Hospital,Shanghai,China(Grant No.SHDC2022CRS010B to Tang S).
文摘Objective This prospective single-arm clinical trial aimed to evaluated the feasibility and safety of the application of the SHURUI system(Beijing Surgerii Technology Co.,Ltd.,Beijing,China),a novel purpose-built robotic system,in single-port robotic radical prostatectomy.Methods Sixteen patients diagnosed with prostate cancer were prospectively enrolled in and underwent robotic radical prostatectomy from October 2021 to August 2022 by the SHURUI single-port robotic surgical system.The demographic and baseline data,surgical,oncological,and functional outcomes as well as follow-up data were recorded.Results The mean operative time was 226.3(standard deviation[SD]52.0)min,and the mean console time was 183.4(SD 48.3)min,with the mean estimated blood loss of 116.3(SD 90.0)mL.The mean length of postoperative hospital stay was 4.50(SD 0.97)days.Two patients had postoperative complications(Clavien-Dindo Grade II),and both patients improved after conservative treatment.All patients’postoperative prostate-specific antigen levels decreased to below 0.2 ng/mL 1 month after discharge.The mean prostate-specific antigen level further decreased to a mean of 0.0219(SD 0.0641)ng/mL 6 months after surgery.Thirty days postoperatively,12 out of 16 patients reported using no more than one urinary pad per day,and all patients reported satisfactory urinary control without the need for pads 6 months after surgery.Conclusion The SHURUI system is safe and feasible in performing radical prostatectomy via both transperitoneal and extraperitoneal approaches.Tumor control and urinary continence were satisfying for patients enrolled in.The next phase involves conducting a large-scale,multicenter randomized controlled trial to thoroughly assess the effectiveness and safety of the new technology in a broader population.
基金supported by the National Key R&D Program of China(2017YFC0211503,2016YFC0207100)the Strategic Priority Research Program(A)of the Chinese Academy of Sciences(XDA23030300)+2 种基金the National Natural Science Foundation of China(21401200,51672273)the Open Research Fund of State Key Laboratory of Multi-phase Complex Systems(MPCS-2017-D-06)the Young Talent Project of the Center for Excellence in Regional Atmospheric Environment,CAS(CERAE201805)~~
文摘The ravages of COVID-19 have forced schools in countries around the world to make a temporary shift from traditional, face-to-face teaching to online teaching. Are teachers in schools prepared to deal with this change? We conducted a survey in which we distributed questionnaires to primary and secondary school teachers in Guangdong Province, China, asking them about their views on various aspects of online education. We received 498,481 questionnaires back, and over 80% of teachers were satisfied with the online resources, and over 68% of teachers were satisfied with the online platform and software. Immediately afterward, we analyzed the differences between urban and rural teachers on specific issues using cross-sectional analysis and chi-square tests and built a neural network model to achieve predictions of teacher satisfaction with an accuracy of nearly 90%. Finally, we analyzed the features that influence the decisions of the neural network. This epidemic has prompted the widespread use of online learning, and the insights we gain today will be helpful in the future.
基金supported by the National Natural Science Foundation of China(51672312,21373275,51808080,21571192)the Fundamental Research Funds for the Central Univsrsity,South-Central University for Nationalities(CZT19006)+2 种基金the Natural Science Foundation Project of CQ CSTC(cstc2018jcyjA 3794)China "post-doctoral innovative talent support program"(BX20180056)China Postdoctoral Science Foundation(2018M643788XB)~~
基金supported by the National Natural Science Foundation of China(51672312,21571192,21373275)the Science and Technology Program of Wuhan(2016010101010018,2015070504020220)+1 种基金the Key Project in the National Science&Technology Pillar Program during the Twelfth Five-Year Plan Period(2015BAB01B01)the Natural Science Foundation of South-Central University for Nationalities(XTZ15016,CZP17062)~~
文摘Unlike the reported leaching technologies of waste superalloys, the process of the “atomized spray-sulfuric acid leaching nickel and cobalt” technology was put forward in the present work according to the compositions of waste superalloys. The effects of sulfuric acid temperature, concentration, leaching time, stirring speed and size of superalloys on leaching of Ni and Co from waste superalloys have been mainly investigated, and the optimum leaching conditions were determined and reported. The leaching rates for nickel and cobalt were 96.68% and 96.63%, respectively, and the contents of nickel and cobalt in leaching slag were 6.77% and 0.96%, respectively. The obtained leaching solution containing Ni and Co could be used for production of Ni and Co products after removal.
基金supported by the National Natural Science Foundation of China(21801090,21831003 and 21621001)the Jilin Scientific and Technological Development Program(20200802003GH)+2 种基金the Scientific Research Project in the Education Department of Jilin Province(JJKH20211044KJ)the Project on Experimental Technique of Jilin University(409020720202)supported by Users with the Excellence Program of Hefei Science Center CAS(2020HSC-UE002)。
文摘The electrocatalytic activity of transition-metal-based compounds is closely related to the electronic configuration.However,optimizing the surface electron spin state of catalysts remains a challenge.Here,we developed a spin-state and delocalized electron regulation method to optimize oxygen evolution reaction(OER)performance by in-situ growth of NiCo_(2)(OH)_(x) using Oswald ripening and coordinating etching process on MXene and plasma treatment.X-ray absorption spectroscopy,magnetic tests and electron paramagnetic resonance reveal that the coupling of NiCo_(2)(OH)_(x) and MXene can induce remarkable spin-state transition of Co^(3+)and transition metal ions electron delocalization,plasma treatment further optimizes the 3 d orbital structure and delocalized electron density.The unique Jahn-Teller phenomenon can be brought by the intermediate spin state(t2 _(g)^(5) e_(g)^(1))of Co^(3+),which benefits from the partial electron occupied egorbitals.This distinct electron configuration(t2_(g)^(5) e_(g)^(1))with unpaired electrons leads to orbital degeneracy,that the adsorption free energy of intermediate species and conductivity were further optimized.The optimized electrocatalyst exhibits excellent OER activity with an overpotential of 268 m V at 10 m A cm^(-2).DFT calculations show that plasma treatment can effectively regulate the d-band center of TMs to optimize the adsorption and improve the OER activity.This approach could guide the rational design and discovery of electrocatalysts with ideal electron configurations in the future.
基金Supported by agrant from the Network Researches of Tumor Precise Radiation Therapy of Ministry of Health of China(No.WKJ2005-3-006)
文摘Objective:Prostate cancer is a form of cancer that develops in the prostate,a gland in the male reproductive system.Prostate cancer tends to develop in men over the age of fifty;it is one of the most prevalent types of cancer in men.This article introduced a new method of prostate cancer treatment with the combination of three dimensional conformal radiation therapy (3D-CRT) and high-intensity focused ultrasound (HIFU),its efficacy was evaluated.Methods:From January 2004 to December 2009,95 patients were diagnosed with prostate cancer,among them,48 patients were received combined therapy with total irradiation of TD 60 Gy/30 Fx and 5 fractions of HIFU treatment,while 47 patients were received with pure 3D-CRT with total irradiation of TD (66-72) Gy/(33-36) Fx.Various indicators were evaluated,such as the local control rate and distant metastasis rate,the changes in blood PSA and fPSA,changes in T-lymphocyte subsets and NK cells,as well as acute adverse reaction of normal tissue.Results:The local response rate difference between the two groups had statistical significance (P < 0.05);the changes in blood PSA and fPSA were significant (P < 0.05);CD3+,CD4+,CD8+,CD4+/CD8+ and NK cells of the combined group increased obviously (P < 0.01),while the latter group had no increase (P > 0.05);the combined group had lower blood cells reduction and II-level acute adverse reaction of rectum,bladder and caput humeri than the pure group,but the II-level acute adverse reaction of urogenital canal in the combined group was higher (P < 0.05).Conclusion:The combined therapy with 3D-CRT and HIFU is a good way for the treatment of aged-related prostate cancer.It can ease the symptoms,control the disease and lengthen the survival time.
基金Supported by National Key Research and Development Program of China(2017YFD0701402-2)
文摘The current cultivation of apple trees mainly relies on grafted seedlings to achieve seedling regeneration of apple trees. The commonly used splice grafting,V-shaped grafting and tongue grafting mostly use plastic film for fixation and sealing. After one year,the wrapped plastic film needs to be removed to avoid affecting the growth of the seedlings. This paper introduces a brand new grafting technology which uses tongue grafting iron nails for fixation and growth fixation wax for sealing( SDRG). The process of mechanized grafting for apple nursery stock is determined,and the fixation and sealing problems with the grafting parts of seedlings are solved. The technology is characterized by quick speed,high efficiency,improved seedling survival rate lower labor cost and great significance to the promotion of industrialized nursery and mechanized grafting.
基金co-supported by the National Natural Science Foundation of China(No.U20B2056)the office of Military and Civilian Integration Devel-opment Committee of Shanghai(No.2020-jmrh1-kj25)the X LAB Joint Innovation Foundation with the Second Academy of CASIC(No.21GFC-JJ02-322)。
文摘Recently,mega Low Earth Orbit(LEO)Satellite Network(LSN)systems have gained more and more attention due to low latency,broadband communications and global coverage for ground users.One of the primary challenges for LSN systems with inter-satellite links is the routing strategy calculation and maintenance,due to LSN constellation scale and dynamic network topology feature.In order to seek an efficient routing strategy,a Q-learning-based dynamic distributed Routing scheme for LSNs(QRLSN)is proposed in this paper.To achieve low end-toend delay and low network traffic overhead load in LSNs,QRLSN adopts a multi-objective optimization method to find the optimal next hop for forwarding data packets.Experimental results demonstrate that the proposed scheme can effectively discover the initial routing strategy and provide long-term Quality of Service(QoS)optimization during the routing maintenance process.In addition,comparison results demonstrate that QRLSN is superior to the virtual-topology-based shortest path routing algorithm.
基金financially supported by the funding support by the National Natural Science Foundation of China(22021001)funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement No 101030782+1 种基金the RYC2021-034254-I grant funded by MCIN/AEI/10.13039/501100011033 and European Union“Next Generation EU/PRTR”financial support from FJC2020-044866-I/MCIN/AEI/10.13039/501100011033 and European Union“Next Generation EU”/PRTR
文摘Hematite(α-Fe_(2)O_(3))is an ideal oxide semiconductor candidate for photoelectrochemical(PEC)water splitting.Doping of Fe_(2)O_(3)is known to benefit the PEC water oxidation efficiency,but despite extensive research efforts,the underlying mechanism still remains elusive.In this work,we report a comprehensive study on the relationship between the electronic structure,interfacial reaction kinetics and PEC activity of Ti-doped Fe_(2)O_(3)photoanodes.The results show that the interfacial charge transfer efficiency at the Fe_(2)O_(3)/electrolyte interface is the main factor in the significant increase of the PEC activity of doped Fe_(2)O_(3).Electrochemical impedance spectroscopy reveals that the interfacial charge transfer efficiency is determined by energy overlap between the water oxidation potential and energy distribution of an intermediate surface state that has been identified as Fe^(IV)=O groups on Fe_(2)O_(3)surface generated during PEC process.Interestingly,the potential energy distribution of this intermediate surface state can be modulated by Ti doping,and a shift towards a more positive potential of the intermediate surface state increases the overlap with the water oxidation potential and thus enhances the kinetics of charge transfer for PEC water splitting.The origin of such potential energy modulation is traced to the inductive effect from Ti-doping on the Fe^(3+)/Fe^(4+)redox transition and the Fe-O bond covalency.Our results provide new insight into the mechanism for the doping effect on the PEC water splitting,introducing new strategies to optimize the PEC activity by tuning the redox properties of active metal oxides.
基金supported by National Natural Science Foundation of China(Nos.21831003,21801090 and 22293041)China Postdoctoral Science Foundation(No.2019M661203)Users with Excellence Program of Hefei Science Center CAS(No.2020HSC-UE002).
文摘Superlattices in crystals,particularly in perovskite oxides with strong correlation effects,can create new states of matter and produce peculiar physicochemical phenomena.However,the newfangled perovskite superlattices depend on physical deposition with unit-cell precision.It has been challenging to explore a new suitable chemical method to tailor perovskite superlattices.Herein,we present a new bottomup strategy to precisely prepare atomic-scale oxide superlattices of(LaMnO_(3))_(1)-(La_(1-x-y)Ca_(x)K_(y)MnO_(3))_(2)in a monodispersed perovskite La_(0.66)Ca_(0.29)K_(0.05)MnO_(3)(LCKMO).The special atomic-scale perovskite superlattices are demonstrated using SAED,HAADF-STEM,XRD,and atomic-resolution elemental mapping.Our experiments reveal that the perovskite superlattices can be fabricated under extreme hydrothermal conditions utilizing ultra-high concentrations of KOH.An approximate molten salt system in the hydrothermal process can induce the disproportionation reaction of MnO_(2)solids,which is vital to the growth of ordered perovskite superlattices.This work not only clarifies the hydrothermal growth process of perovskite oxides in extreme conditions,but also proposes a novel engineering route toward perovskite superlattices.
基金Natural Science Foundation of Guangdong Province(No.2021A1515011373)
文摘To the Editor:Chronic thromboembolic pulmonary hypertension(CTEPH)is a chronic progressive disease in which pulmonary artery pressure(PAP)increases and eventually leads to right heart failure and death.Balloon pulmonary angioplasty(BPA)is a new and effective treatment for CTEPH patients who are unsuitable for surgery or who develop recurrent or persistent pulmonary hypertension after pulmonary endarterectomy(PEA).In recent years,major medical centers at home and abroad have been gradually developing and improving BPA,but overall,a unified treatment process and complication control strategy is lacking.
文摘The combination of covalent organic framework(COF)photosensitizers with molecular cocatalysts is a promising avenue for photocatalytic carbon dioxide(CO_(2))reduction.Here,a series of isostructural COFs was synthesized using linkers of different lengths,with or without partial fluorination.These COFs were investigated for photocatalytic CO_(2)reduction under visible-light irradiation when combined with cobalt(II)bipyridine complexes as a cocatalyst.Fluorination was found to enhance both CO_(2)affinity and catalytic activity,and a partially fluorinated COF,FBP-COF,achieved the highest CO_(2)-to-CO conversion efficiency,showing a carbon monoxide(CO)generation rate of 2.08 mmol h−1 g−1 and a 90%CO selectivity.FBP-COF also showed good stability under sacrificial conditions,generating CO for 50 h with a turnover number of 91.5.This activity is much higher than a homogeneous system using ruthenium bipyridine complexes as the photosensitizer combined with the same cobalt bipyridine complexes.
基金This work was supported in part by the grants from the National High Technology Research and Development Program of China(No.2004BA757C)the Key Project of Zhejiang Province(NO.011102465).
文摘This study aims to produce an effective subunit vaccine against infectious bursal disease virus (IBDV). The genes of chicken interleukin-2 (ChIL-2) and IBDV viral protein 2 (VP2) were amplified and fused by splice overlap extension-polymerase chain reaction (SOE-PCR). The fusion gene was digested by EcoR I/Kpn I and inserted into pBacPAK8 vector, resulting in recombinant transfer plasmid pBacPakVP2-IL2. The recombinant plasmid was transfected into Sf-9 cells accompanied with hybrid nuclear polyhedrosis virus (HyNPV) genome DNA and lipofectin. Plaque-purification indicated that we had got the recombinant Hy-VP2-IL2. Fusion protein VP2-IL2 was expressed effectively both in insect cells and bombyx mori. The expression of fusion protein was confirmed by ELISA, SDS-PAGE and Western blotting assay, respectively. This efficient system allows us to meet the need for inexpensive vaccines required by the poultry industry. Cellular & Molecular Immunology. 2005;2(3):231-235.
基金supported by the National High Technology Research and Development Program of China(2012AA062702)the strategic project of the Chinese Academy of Sciences(XDB05050000)
文摘The design and synthesis of highly active non-noble metal oxide catalysts, such as transition- and rare-earth-metal oxides, have attracted significant attention because of their high efficiency and low cost and the resultant potential applications for the degradation of volatile organic compounds(VOCs). The structure-activity relationships have been well-studied and used to facilitate design of the structure and composition of highly active catalysts. Recently, non-noble metal oxides with porous structures have been used as catalysts for deep oxidation of VOCs, such as aromatic hydrocarbons, aliphatic compounds, aldehydes, and alcohols, with comparable activities to their noble metal counterparts. This review summarizes the growing literature regarding the use of porous metal oxides for the catalytic removal of VOCs, with emphasis on design of the composition and structure and typical synthetic technologies.
基金Project supported by the National Natural Science Foundation of China(61675067,51675174,61575062,61474042)the Scientific Research Fund of Hunan Provincial Education Department(16C0627,17B090)the Natural Science Foundation of Hunan Province,China(2016JJ2059,2018JJ3138)
文摘In this paper, we demonstrated trace of dye molecules in living plants. The NaGdF4:Yb^(3+),Er^(3+) nanoparticles probe was used to detect the rhodamine B(RhB) in bean sprout. It is found that the fluorescencedye can be efficiently imbibed during the growing process and the absorbance presented a position dependence effect, which was supported by the upconversion spectra and the fluorescent image characterization. In addition, the concentration of the residual RhB in bean sprout can be efficiently traced by the synthesized probe based on the fluorescent resonant energy transfer. Finally, the relation between the excitation power, concentration and the ratio of yellow to green emission are discussed in detail. These results can be helpful in understanding the RhB dye molecules absorbance process in vegetable growth and provide an efficient way to trace the residual dyes in vivo plant.