Objective To evaluate the clinical effects of Ilizarov external fixator for maluninon of obsolete calcaneal fracture of Stephen Type Ⅲ.Methods From July 2006 to February 2009,25 patients suffering from maluninon of o...Objective To evaluate the clinical effects of Ilizarov external fixator for maluninon of obsolete calcaneal fracture of Stephen Type Ⅲ.Methods From July 2006 to February 2009,25 patients suffering from maluninon of obsolete calcaneal展开更多
Purpose： llizarov ring fixator and limb reconstruction system （LRS） fixators have been used in the management of complex tibial fractures with severe soft tissue injuries, compound tibial fractures, and infected ti...Purpose： llizarov ring fixator and limb reconstruction system （LRS） fixators have been used in the management of complex tibial fractures with severe soft tissue injuries, compound tibial fractures, and infected tibial nonunion for which conventional internal fixation cannot be contemplated. Fracture union and distraction osteogenesis can be done simultaneously with these external fixators, allowing early weight bearing. Several previous studies have shown almost equal results of rail and ring fixators for the compound tibial shaft fractures. Thus we performed a prospective study to evaluate the union rate, functional outcome and amount of limb lengthening after the treatment of compound tibial shaft fractures with or without infected nonunion by ring or LRS fixators. Methods： This prospective study was done at Sarojini Naidu Medical College and Hospital, Agra, India and included 32 patients of compound tibial shaft fractures with or without infected nonunion. There were 26 males and 6 females and the average age was 40 years. Patients were randomly divided into two groups （n - 16 for each）： one underwent llizarov fixation and the other received LRS fixation. Cases were followed up for 3-24 months, 6 months on average from September 2012 to October 2014. Functional and radiological outcomes were assessed using the Association for the Study and Application of Methods of llizarov （ASAMI） criteria for both rail and ring fixators. Results： Union was achieved in all cases. Radiological outcome was found excellent in 68.75%, good in 18.75% and fair in 12.50% of cases treated by rail fixators whereas it was excellent in 56.25%, good in 18.75%, fair in 12.50% and poor in 12.50% of cases treated by ring fixators. Functional result was satis- factory in 75.00% of cases treated by rail fixator and 68.75% of cases treated by ring fixators whereas the corresponding rate of unsatisfactory was 25.00% vs. 31.25%. Conclusion： In our short-term assessment, LRS fixators show a better result than llizarov fixators in terms of fracture union and functional outcome with soft tissue care and limb length.展开更多
Biological nitrogen fixation(BNF)and photosynthetic carbon fixation underpin food production and climate mitigation,yet natural systems are constrained by oxygen sensitivity,high energy demand,and inefficient catalyst...Biological nitrogen fixation(BNF)and photosynthetic carbon fixation underpin food production and climate mitigation,yet natural systems are constrained by oxygen sensitivity,high energy demand,and inefficient catalysts.This review synthesizes advances that recast these processes as engineering targets and proposes a conceptual roadmap that bridges synthetic symbioses with the synthetic biology of enzymes and pathways.For BNF,progress spans cross-kingdom strategies—from refactoring nif gene sets and targeting nitrogenase assembly to eukaryotic organelles,to engineering plant-associated diazotrophs,rhizosphere control circuits,and emerging nodule-like microenvironments.For carbon assimilation,new-to-nature CO_(2)-fixation modules and photorespiratory bypasses illustrate how pathway redesign and alternative carboxylases can circumvent key Calvin–Benson–Bassham limitations,and expanding photosynthetic light capture offers additional leverage.Across these domains,we extract common design principles:(i)nitrogenase output is increasingly governed by carbon/energy supply and electron delivery as much as by oxygen protection;(ii)robust function requires compartment-aware enzyme–chassis coordination,substrate channeling,and dynamic regulation using sensors and control circuits;and(iii)scalable implementation may benefit from distributing metabolic labor across engineered consortia rather than forcing all functions into a single host.We discuss enabling technologies—including AI-guided protein design and directed evolution,cell-free prototyping,chassis toolkits,and materials/bioelectrochemical interfaces—that can accelerate design–build–test–learn cycles and reduce barriers to deployment.Together,these insights define a path toward integrated nitrogen and carbon fixation systems for low-emission agriculture and biomanufacturing.展开更多
The direct transformation of dinitrogen(N_(2)) into nitrogen-containing organic compounds holds substantial importance.In this work,we report a titanium-promoted method for the conversion of N_(2) to N-methylimides.In...The direct transformation of dinitrogen(N_(2)) into nitrogen-containing organic compounds holds substantial importance.In this work,we report a titanium-promoted method for the conversion of N_(2) to N-methylimides.Initially,the N_(2)-bridging end-on dititanium side-on dipotassium complex[{(Tren^(TMS))Ti}_(2)(μ-η^(1):η^(1):η^(2):η^(2)-N_(2)K_(2))] underwent simultaneous disproportionation and N-methylation reactions in the presence of methyl trifluoromethanesulfonate(Me OTf),yielding [{(N^(Me,TMS)NN^(TMS)_(2))Ti}(μ-NMe)]_(2) with complete cleavage of the N≡N bond.The nucleophilicity of the N-methylated intermediate allowed it to react with electrophilic reagents such as trimethylchlorosilane(TMSCl) to form heptamethyldisilazane,or with acyl chlorides to generate N-methylimides.Moreover,nitrogen-15(^(15)N) labeled experiments provided a novel approach to synthesizing ^(15)N-labeled methylimides.展开更多
Photocatalytic nitrogen fixation (PNF) is a promising alternative to the Haber-Bosch process.It achieves green ammonia production by utilizing solar energy for nitrogen fixation under mild conditions.While nanoscale p...Photocatalytic nitrogen fixation (PNF) is a promising alternative to the Haber-Bosch process.It achieves green ammonia production by utilizing solar energy for nitrogen fixation under mild conditions.While nanoscale photocatalysts offer enhanced performance due to their high surface area and abundant active sites,their small size makes them difficult to recover and prone to agglomeration.These bottlenecks severely limit industrial application.A promising solution is to immobilize the catalysts onto support surfaces.This paper provides a systematic review of recent advances in the design of immobilized photocatalysts for ammonia synthesis.It begins by outlining the key benefits of immobilization strategies,particularly in improving catalyst stability,recyclability,and overall photocatalytic performance.The working mechanisms and features of various immobilization techniques are then categorized and explained,covering physical adsorption/deposition,chemical bonding,in situ growth,and hybrid physico-chemical methods.Supported materials and common substrate types are also summarized.Furthermore,the widely used configurations of photoreactors suitable for immobilized systems are introduced.Finally,the review identifies current research limitations and challenges,and offers perspectives on future developments in the field of immobilized photocatalysis.展开更多
Soybean is an important source of oil,protein,and feed.However,its yield is far below that of major cereal crops.The green revolution increased the yield of cereal crops partially through high-density planting of lodg...Soybean is an important source of oil,protein,and feed.However,its yield is far below that of major cereal crops.The green revolution increased the yield of cereal crops partially through high-density planting of lodging-resistant semi-dwarf varieties,but required more nitrogen fertilizers,posing an environmental threat.Genes that can improve nitrogen use efficiency need to be integrated into semi-dwarf varieties to avoid the overuse of fertilizers without the loss of dwarfism.Unlike cereal crops,soybean can assimilate atmospheric nitrogen through symbiotic bacteria.Here,we created new alleles of Gm GID1-2(Glycine max GIBBERELLIN INSENSITIVE DWARF 1-2)using clustered regularly interspaced short palindromic repeats(CRISPR)/CRISPR-associated nuclease 9(Cas9)editing,which improved soybean architecture,yield,seed oil content,and nitrogen fixation,by regulation of important pathways and known genes related to branching,lipid metabolism,and nodule symbiosis.Gm GID1-2 knockout reduced plant height,and increased stem diameter and strength,number of branches,nodes on the primary stem,pods,and seeds per plant,leading to an increase in seed weight per plant and yield in soybean.The nodule number,nodule weight,nitrogenase activity,and nitrogen content were also improved in Gm GID1-2knockout soybean lines,which is novel compared with the semi-dwarf genes in cereal crops.No loss-of-function allele for Gm GID1-2 was identified in soybean germplasm and the edited Gm GID1-2s are superior to the natural alleles,suggesting the Gm GID1-2 knockout mutants generated in this study are valuable genetic resources to further improve soybean yield and seed oil content in future breeding programs.This study illustrates the pleiotropic functions of the GID1 knockout alleles with positive effects on plant architecture,yield,and nitrogen fixation in soybean,which provides a promising strategy toward sustainable agriculture.展开更多
The rate-limited activation of N≡N triple bonds with high bond energies has been a bottleneck in photoctalytic nitrogen fixation.Here,polymeric carbon nitride with frustrated Lewis pairs(FLPs) was constructed by inse...The rate-limited activation of N≡N triple bonds with high bond energies has been a bottleneck in photoctalytic nitrogen fixation.Here,polymeric carbon nitride with frustrated Lewis pairs(FLPs) was constructed by inserting electron-deficient magnesium into g-C_(3)N_(4)(CN).The synergistic interactions between Mg and amino groups in CN led to a 7.2 fold increase in the photoreactivity of nitrogen(N_(2)) fixation by carbon nitride.展开更多
AIM:To evaluate the clinical outcomes of a new minimally invasive technique using horizontal mattress sutures and Hoffman pockets for four-point refixation of dislocated fourhaptic intraocular lenses(IOLs).METHODS:Thi...AIM:To evaluate the clinical outcomes of a new minimally invasive technique using horizontal mattress sutures and Hoffman pockets for four-point refixation of dislocated fourhaptic intraocular lenses(IOLs).METHODS:This retrospective consecutive case series included eyes with dislocated Akreos AO60 IOLs underwent scleral refixation using a horizontal mattress doubleneedle suture technique with intralamellar knot burial via Hoffman pockets.Clinical outcomes assessed included pre-and postoperative best-corrected visual acuity(BCVA),intraocular pressure(IOP),spherical equivalent(SE),suture duration,IOL centration,and perioperative complications.RESULTS:A total of 10 eyes from 10 patients(6 males)were included.The mean age at the time of IOL refixation was 53.10±13.07y(range:28-68y).The mean interval between initial IOL implantation and dislocation was 8.44±3.54y.The mean postoperative follow-up duration was 11.45±10.30mo.Surgical time averaged 15.3±1.77min,with no intraoperative complications.The mean axial length was 27.16±4.35 mm,with high myopia(HM)as the leading comorbidity(4/10 eyes).Postoperative BCVA significantly improved compared to preoperative values(P=0.025).Postoperative SE was significantly improved compared with preoperative(P=0.01).All IOLs remained centered throughout follow-up.CONCLUSION:This minimally invasive four-point scleral fixation technique offers a safe and effective refixation strategy for dislocated four-haptic IOLs.The horizontal mattress suture configuration combined with Hoffman pockets facilitates durable centration,avoids conjunctival dissection,and could be adopted into routine surgical practice.展开更多
Photocatalytic nitrogen fixation has emerged as a sustainable alternative for ammonia synthesis,playing a crucial role in alleviating energy shortages and environmental pollution.In this study,PbBiO_(2)Br was applied ...Photocatalytic nitrogen fixation has emerged as a sustainable alternative for ammonia synthesis,playing a crucial role in alleviating energy shortages and environmental pollution.In this study,PbBiO_(2)Br was applied to photocatalytic nitrogen fixation for the first time,and its photocatalytic performance was effectively enhanced through Cu doping.The catalyst was synthesized via a simple reduction method,and its morphology,structure,and physicochemical properties were systematically investigated using various characterization techniques and density functional theory calculations.The results revealed that the incorporation of Cu2+partially replaced Pb2+,inducing lattice distortion in PbBiO_(2)Br,promoting the formation of oxygen vacancies,and modifying its electronic band structure.Specifically,Cu doping led to a slight bandgap narrowing,a reduction in work function,and a significant upward shift in the conduction band position.These changes enhanced light absorption,facilitated charge carrier migration and separation,and improved the reduction ability of photogenerated electrons.Moreover,Cu doping promoted N_(2)adsorption and activation.Consequently,the photocatalytic nitrogen fixation performance of Cu-doped PbBiO_(2)Br was significantly enhanced,achieving an optimal nitrogen fixation rate of 293μmol L^(−1)g^(−1)h^(−1),which is 3.6 times higher than that of pristine PbBiO_(2)Br.Additionally,Cu–PbBiO_(2)Br also showed good activity in the photocatalytic degradation of RhB,with a degradation rate 4.6 times higher than that of PbBiO_(2)Br.This work offers new insights into the application of PbBiO_(2)Br in photocatalytic nitrogen fixation and offers valuable guidance for the development of highly efficient nitrogen fixation materials in the future.展开更多
Carbon dioxide(CO_(2))is the main greenhouse gas(GHG)released by human activities.The substitution of fossil resources by biomass as a bio-renewable resource,has significant potential to reduce GHG emissions.The appro...Carbon dioxide(CO_(2))is the main greenhouse gas(GHG)released by human activities.The substitution of fossil resources by biomass as a bio-renewable resource,has significant potential to reduce GHG emissions.The approach to biomass,as the only true full-scale alternative to fossil resources,is progressing rapidly.Converting biomass into furanic compounds,as versatile platform chemicals for synthesizing a wide range of bio-based products is the cornerstone of sustainable technologies.The extensive body of this review combines the biomass valorization to furanic compounds by CO_(2)utilization and furanic compounds conversion by CO_(2)fixation.These processes can be strategically applied through both‘thermochemical’and‘electrochemical’pathways,by utilizing CO_(2)from the atmosphere or industrial emission point and returning it to the natural carbon cycle.In the thermochemical pathway CO_(2)acts as a carbon source(carboxylation and polymerization)or active reaction assistant in the biomass conversion(CO_(2)-assisted conversion),without altering its oxidation state,facilitating the synthesis of valuable products and polymers.Conversely,in the electrochemical pathway,CO_(2)can be used as a carbon source(electrocarboxylation)to give the corresponding carboxylic acid,or it can undergo reduction,yielding methanol,carbon monoxide(CO),formic acid,and analogous compounds,while on the other side,furanic compounds undergo oxidation yielding high-value-added chemicals.Finally,potential future research directions are suggested to promote CO_(2)utilization and fixation in the valorization of biomass-derived furanic compounds,and challenges facing further research are highlighted.展开更多
Photocatalysis uses solar energy to convert nitrogen and water directly into ammonia,helping reduce dependence on fossil fuels and offering a way to integrate the nitrogen cycle into a clean energy network.Ohmic junct...Photocatalysis uses solar energy to convert nitrogen and water directly into ammonia,helping reduce dependence on fossil fuels and offering a way to integrate the nitrogen cycle into a clean energy network.Ohmic junctions between metals and semiconductors have demonstrated significant advantages in enhancing stability and reducing carrier recombination,but their application in photocatalytic nitrogen fixation is limited due to the difficulty of work function matching and the complexity of fabrication processes.In this study,density functional theory(DFT) calculations were used to confirm the work function matching between Bi and Bi_(2)Ti_(2)O_(7)(BTO),ensuring the formation of an Ohmic junction.A Bi-Bi_(2)Ti_(2)O_(7)(B-BTO) composite was successfully synthesized via a one-step hydrothermal method,using bismuth nitrate and titanium sulfate as precursors.Compared to pure BTO,the B-BTO heterojunction,driven by dual electron injection from both metal Bi and BTO,significantly increased the ammonia synthesis rate to 686.95 μmol g^(-1)h^(-1),making it the most active nitrogen fixation material among similar pyrochlorebased catalysts to date.The differential charge density calculations,photocurrent(i-t) measurements,and photoluminescence(PL) tests further validate the role of Ohmic contacts in enhancing charge transfer and prolonging carrier lifetimes.This research provides valuable insight into the application of Ohmic junctions in photocatalytic nitrogen fixation and contributes to advancements in this field.展开更多
Global warming caused by the emission of CO_(2) in industrial flue gas has attractedmore and more attention.Therefore,to fix CO_(2) with high efficiency and environmentally friendly had become the hot research field.C...Global warming caused by the emission of CO_(2) in industrial flue gas has attractedmore and more attention.Therefore,to fix CO_(2) with high efficiency and environmentally friendly had become the hot research field.Compared with the traditional coal-fired power plant flue gas emission reduction technology,carbon fixation and emission reduction by microalgae is considered as a promising technology due to the advantages of simple process equipment,convenient operation and environmental protection.When the flue gas is treated by microalgae carbon fixation and emission reduction technology,microalgae cells can fix CO_(2) in the flue gas through photosynthesis,and simultaneously absorb NO_(x) and SO_(x) as nitrogen and sulfur sources required for growth.Meanwhile,they can also absorb mercury,selenium,arsenic,cadmium,lead and other heavy metal ions in the flue gas to obtain microalgae biomass.The obtained microalgae biomass can be further transformed into high valueadded products,which has broad development prospects.This paper reviews the mechanisms and pathways of CO_(2) sequestration,the mechanism and impacts of microalgal emission reduction of flue gas pollutants,and the applications of carbon sequestration in industrial flue gas by microalgae.Finally,this paper provides some guidelines and prospects for the research and application of green emission reduction technology for industrial flue gas.展开更多
Plant synthetic biology has emerged as a transformative field in agriculture,offering innovative solutions to enhance food security,provide resilience to climate change,and transition to sustainable farming practices....Plant synthetic biology has emerged as a transformative field in agriculture,offering innovative solutions to enhance food security,provide resilience to climate change,and transition to sustainable farming practices.By integrating advanced genetic tools,computational modeling,and systems biology,researchers can precisely modify plant genomes to enhance traits such as yield,stress tolerance,and nutrient use efficiency.The ability to design plants with specific characteristics tailored to diverse environmental conditions and agricultural needs holds great potential to address global food security challenges.Here,we highlight recent advancements and applications of plant synthetic biology in agriculture,focusing on key areas such as photosynthetic efficiency,nitrogen fixation,drought tolerance,pathogen resistance,nutrient use efficiency,biofortification,climate resilience,microbiology engineering,synthetic plant genomes,and the integration of artificial intelligence with synthetic biology.These innovations aim to maximize resource use efficiency,reduce reliance on external inputs,and mitigate environmental impacts associated with conventional agricultural practices.Despite challenges related to regulatory approval and public acceptance,the integration of synthetic biology in agriculture holds immense promise for creating more resilient and sustainable agricultural systems,contributing to global food security and environmental sustainability.Rigorous multi-field testing of these approaches will undoubtedly be required to ensure reproducibility.展开更多
Potassium hydroxide(KOH)was introduced into the molybdenite roasting process to convert molybdenum(Mo)and sulfur(S)into water-soluble potassium molybdate(K_(2)MoO_(4))and potassium sulfate(K_(2)SO_(4)).Roasting with a...Potassium hydroxide(KOH)was introduced into the molybdenite roasting process to convert molybdenum(Mo)and sulfur(S)into water-soluble potassium molybdate(K_(2)MoO_(4))and potassium sulfate(K_(2)SO_(4)).Roasting with a 1.8-fold excess of KOH at 400℃ for 3 h enabled the leaching of over 99%of Mo from the molybdenum calcine using water.A precipitation method involving potassium–magnesium(K-Mg)salts was proposed for impurity removal.Under the conditions of pH 11,30℃,excess coefficient of 1.7 for Mg salts,and a duration of 1 h,98.37%of phosphorus(P)was removed from the K_(2)MoO_(4) solution.With post-purification,over 99%of Mo crystallized upon adjustment of pH to 1.Subsequently,S and K were recovered as K_(2)SO_(4) fertilizer from the crystalline mother liquor.An environmentally sustainable approach was proposed to conduct molybdenite production and ensure the efficient recovery of both Mo and S.展开更多
Biological nitrogen fixation(BNF)is a crucial process that provides bioavailable nitrogen and supports primary production in freshwater lake ecosystems.However,the characteristics of diazotrophic community and nitroge...Biological nitrogen fixation(BNF)is a crucial process that provides bioavailable nitrogen and supports primary production in freshwater lake ecosystems.However,the characteristics of diazotrophic community and nitrogenase activity in freshwater lake sediments remain poorly understood.Here,we investigated the diazotrophic communities and nitrogenase activities in the sediments of three large river-connected freshwater lakes in eastern China using 15N-isotope tracing and nifH sequencing.The sediments in these lakes contained diverse nitrogenase genes that were phylogenetically grouped into Clusters I and III.The diazotrophic communities in the sedimentswere dominated by stochastic processes in Hongze Lake and Taihu Lake,which had heterogeneous habitats and shallower water depths,while in Poyang Lake,which had deeper water and a shorter hydraulic retention time,the assembly of the diazotrophic community in the sediments was dominated by homogeneous selection processes.Temperature and water depth were also found the key environmental factors affecting the sediment diazotrophic communities.Sediment nitrogenase activities varied in the three lakes and within distinct regions of an individual lake,ranging from 0 to 14.58 nmol/(kg·hr).Nitrogenase activity was significantly correlated with ferric iron,total phosphorus,and organic matter contents.Our results suggested that freshwater lake sediment contain high diversity of nitrogen-fixing microorganisms with potential metabolic diversity,and the community assembly patterns and nitrogenase activities varied with the lake habitat.展开更多
Electrochemical CO_(2)reduction has been considered a promising approach to neutralizing the global CO_(2)level.As an intriguing technique,metal-CO_(2)battery devices can not only capture CO_(2)into valuable carbonace...Electrochemical CO_(2)reduction has been considered a promising approach to neutralizing the global CO_(2)level.As an intriguing technique,metal-CO_(2)battery devices can not only capture CO_(2)into valuable carbonaceous chem-icals and reduce the CO_(2)concentration in the atmosphere but enable energy conversion.Among metal-CO_(2)batteries,aqueous Zn–CO_(2)batteries,especially rechargeable systems,exhibit flexible CO_(2)electrochemistry in terms of multi-carbon chemicals,which are gaseous or water-soluble,in favor of rechargeability and cycling durability of aqueous battery systems.Despite the increasing number of publications on Zn–CO_(2)batteries in the past three years,this field is still in its beginning stage and facing many challenges considering the capability of CO_(2)fixation and battery performance.Herein,we present a timely and overall summary of the recent progress in Zn–CO_(2)batteries,including fundamental mechanisms,affecting factors on electrochemical performance,catalyst cathodes,and electrolytes(catholytes and anolytes).Besides,we assess the application potential of Zn–CO_(2)batteries and compare this with those of alkali metal-CO_(2)batteries based on CO_(2)fixation and battery perfor-mance.Finally,we point out some current challenges for the further development of Zn–CO_(2)batteries and put forward perspectives of the research directions for practical applications of Zn–CO_(2)batteries in the future.展开更多
Development of robust electrocatalyst for oxygen reduction reaction(ORR)in a seawater electrolyte is the key to realize seawater electrolyte-based zinc-air batteries(SZABs).Herein,constructing a local electric field c...Development of robust electrocatalyst for oxygen reduction reaction(ORR)in a seawater electrolyte is the key to realize seawater electrolyte-based zinc-air batteries(SZABs).Herein,constructing a local electric field coupled with chloride ions(Cl-)fixation strategy in dual single-atom catalysts(DSACs)was proposed,and the resultant catalyst delivered considerable ORR performance in a seawater electrolyte,with a high half-wave potential(E_(1/2))of 0.868 V and a good maximum power density(Pmax)of 182 mW·cm^(−2)in the assembled SZABs,much higher than those of the Pt/C catalyst(E_(1/2):0.846 V;Pmax:150 mW·cm^(−2)).The in-situ characterization and theoretical calculations revealed that the Fe sites have a higher Cl^(−)adsorption affinity than the Co sites,and preferentially adsorbs Cl^(−)in a seawater electrolyte during the ORR process,and thus constructs a low-concentration Cl^(−)local microenvironment through the common-ion exclusion effect,which prevents Cl^(−)adsorption and corrosion in the Co active centers,achieving impressive catalytic stability.In addition,the directional charge movement between Fe and Co atomic pairs establishes a local electric field,optimizing the adsorption energy of Co sites for oxygen-containing intermediates,and further improving the ORR activity.展开更多
Symbiotic nitrogen fixation in members of the Fabaceae family is highly efficient and beneficial for global agriculture,but not all species in this family form root nodules with rhizobial bacteria.Nodulation mainly oc...Symbiotic nitrogen fixation in members of the Fabaceae family is highly efficient and beneficial for global agriculture,but not all species in this family form root nodules with rhizobial bacteria.Nodulation mainly occurs in plants belonging to the Papilionoideae and Caesalpinioideae subfamilies(Tederso0 et al.,2018;van Velzen et al.,2019).Nodulation mechanisms in Fabaceae are well studied(Yang et al.,2022),and genomic comparisons of nodulating and non-nodulating host species can provide valuable insights into the evolutionary and genetic basis of this key process.展开更多
文摘Objective To evaluate the clinical effects of Ilizarov external fixator for maluninon of obsolete calcaneal fracture of Stephen Type Ⅲ.Methods From July 2006 to February 2009,25 patients suffering from maluninon of obsolete calcaneal
文摘Purpose： llizarov ring fixator and limb reconstruction system （LRS） fixators have been used in the management of complex tibial fractures with severe soft tissue injuries, compound tibial fractures, and infected tibial nonunion for which conventional internal fixation cannot be contemplated. Fracture union and distraction osteogenesis can be done simultaneously with these external fixators, allowing early weight bearing. Several previous studies have shown almost equal results of rail and ring fixators for the compound tibial shaft fractures. Thus we performed a prospective study to evaluate the union rate, functional outcome and amount of limb lengthening after the treatment of compound tibial shaft fractures with or without infected nonunion by ring or LRS fixators. Methods： This prospective study was done at Sarojini Naidu Medical College and Hospital, Agra, India and included 32 patients of compound tibial shaft fractures with or without infected nonunion. There were 26 males and 6 females and the average age was 40 years. Patients were randomly divided into two groups （n - 16 for each）： one underwent llizarov fixation and the other received LRS fixation. Cases were followed up for 3-24 months, 6 months on average from September 2012 to October 2014. Functional and radiological outcomes were assessed using the Association for the Study and Application of Methods of llizarov （ASAMI） criteria for both rail and ring fixators. Results： Union was achieved in all cases. Radiological outcome was found excellent in 68.75%, good in 18.75% and fair in 12.50% of cases treated by rail fixators whereas it was excellent in 56.25%, good in 18.75%, fair in 12.50% and poor in 12.50% of cases treated by ring fixators. Functional result was satis- factory in 75.00% of cases treated by rail fixator and 68.75% of cases treated by ring fixators whereas the corresponding rate of unsatisfactory was 25.00% vs. 31.25%. Conclusion： In our short-term assessment, LRS fixators show a better result than llizarov fixators in terms of fracture union and functional outcome with soft tissue care and limb length.
基金supported by the funds of the Ministry of Science and Technology of China(2019YFA0904700)the National Natural Science Foundation of China(32471477)to Cheng Qi.
文摘Biological nitrogen fixation(BNF)and photosynthetic carbon fixation underpin food production and climate mitigation,yet natural systems are constrained by oxygen sensitivity,high energy demand,and inefficient catalysts.This review synthesizes advances that recast these processes as engineering targets and proposes a conceptual roadmap that bridges synthetic symbioses with the synthetic biology of enzymes and pathways.For BNF,progress spans cross-kingdom strategies—from refactoring nif gene sets and targeting nitrogenase assembly to eukaryotic organelles,to engineering plant-associated diazotrophs,rhizosphere control circuits,and emerging nodule-like microenvironments.For carbon assimilation,new-to-nature CO_(2)-fixation modules and photorespiratory bypasses illustrate how pathway redesign and alternative carboxylases can circumvent key Calvin–Benson–Bassham limitations,and expanding photosynthetic light capture offers additional leverage.Across these domains,we extract common design principles:(i)nitrogenase output is increasingly governed by carbon/energy supply and electron delivery as much as by oxygen protection;(ii)robust function requires compartment-aware enzyme–chassis coordination,substrate channeling,and dynamic regulation using sensors and control circuits;and(iii)scalable implementation may benefit from distributing metabolic labor across engineered consortia rather than forcing all functions into a single host.We discuss enabling technologies—including AI-guided protein design and directed evolution,cell-free prototyping,chassis toolkits,and materials/bioelectrochemical interfaces—that can accelerate design–build–test–learn cycles and reduce barriers to deployment.Together,these insights define a path toward integrated nitrogen and carbon fixation systems for low-emission agriculture and biomanufacturing.
基金Financial supports from the National Natural Science Foundation of China (Nos.22025109,22371283)the National Key R&D Program of China (No.2023YFA1507902)+1 种基金CAS Project for Young Scientists in Basic Research (No.YSBR-050)the State Key Laboratory of Fine Chemicals,Dalian University of Technology (No.KF2102) are gratefully acknowledged。
文摘The direct transformation of dinitrogen(N_(2)) into nitrogen-containing organic compounds holds substantial importance.In this work,we report a titanium-promoted method for the conversion of N_(2) to N-methylimides.Initially,the N_(2)-bridging end-on dititanium side-on dipotassium complex[{(Tren^(TMS))Ti}_(2)(μ-η^(1):η^(1):η^(2):η^(2)-N_(2)K_(2))] underwent simultaneous disproportionation and N-methylation reactions in the presence of methyl trifluoromethanesulfonate(Me OTf),yielding [{(N^(Me,TMS)NN^(TMS)_(2))Ti}(μ-NMe)]_(2) with complete cleavage of the N≡N bond.The nucleophilicity of the N-methylated intermediate allowed it to react with electrophilic reagents such as trimethylchlorosilane(TMSCl) to form heptamethyldisilazane,or with acyl chlorides to generate N-methylimides.Moreover,nitrogen-15(^(15)N) labeled experiments provided a novel approach to synthesizing ^(15)N-labeled methylimides.
基金support for carrying out this work was provided by the Doctoral Research Foundation of Weifang University(2024BS20)Science and Technology Development Plan Foundation of Weifang(2024GX017).
文摘Photocatalytic nitrogen fixation (PNF) is a promising alternative to the Haber-Bosch process.It achieves green ammonia production by utilizing solar energy for nitrogen fixation under mild conditions.While nanoscale photocatalysts offer enhanced performance due to their high surface area and abundant active sites,their small size makes them difficult to recover and prone to agglomeration.These bottlenecks severely limit industrial application.A promising solution is to immobilize the catalysts onto support surfaces.This paper provides a systematic review of recent advances in the design of immobilized photocatalysts for ammonia synthesis.It begins by outlining the key benefits of immobilization strategies,particularly in improving catalyst stability,recyclability,and overall photocatalytic performance.The working mechanisms and features of various immobilization techniques are then categorized and explained,covering physical adsorption/deposition,chemical bonding,in situ growth,and hybrid physico-chemical methods.Supported materials and common substrate types are also summarized.Furthermore,the widely used configurations of photoreactors suitable for immobilized systems are introduced.Finally,the review identifies current research limitations and challenges,and offers perspectives on future developments in the field of immobilized photocatalysis.
基金supported by the National Natural Science Foundation of China(32372192)the Core Technology Development for Breeding Program of Jiangsu Province(JBGS-2021-014)Jiangsu Key Laboratory of Soybean Biotechnology and Intelligent Breeding(BM2024005)。
文摘Soybean is an important source of oil,protein,and feed.However,its yield is far below that of major cereal crops.The green revolution increased the yield of cereal crops partially through high-density planting of lodging-resistant semi-dwarf varieties,but required more nitrogen fertilizers,posing an environmental threat.Genes that can improve nitrogen use efficiency need to be integrated into semi-dwarf varieties to avoid the overuse of fertilizers without the loss of dwarfism.Unlike cereal crops,soybean can assimilate atmospheric nitrogen through symbiotic bacteria.Here,we created new alleles of Gm GID1-2(Glycine max GIBBERELLIN INSENSITIVE DWARF 1-2)using clustered regularly interspaced short palindromic repeats(CRISPR)/CRISPR-associated nuclease 9(Cas9)editing,which improved soybean architecture,yield,seed oil content,and nitrogen fixation,by regulation of important pathways and known genes related to branching,lipid metabolism,and nodule symbiosis.Gm GID1-2 knockout reduced plant height,and increased stem diameter and strength,number of branches,nodes on the primary stem,pods,and seeds per plant,leading to an increase in seed weight per plant and yield in soybean.The nodule number,nodule weight,nitrogenase activity,and nitrogen content were also improved in Gm GID1-2knockout soybean lines,which is novel compared with the semi-dwarf genes in cereal crops.No loss-of-function allele for Gm GID1-2 was identified in soybean germplasm and the edited Gm GID1-2s are superior to the natural alleles,suggesting the Gm GID1-2 knockout mutants generated in this study are valuable genetic resources to further improve soybean yield and seed oil content in future breeding programs.This study illustrates the pleiotropic functions of the GID1 knockout alleles with positive effects on plant architecture,yield,and nitrogen fixation in soybean,which provides a promising strategy toward sustainable agriculture.
基金supported by the National Natural Science Foundation of China (No.42377227)Beijing Natural Science Foundation (No.2232061)。
文摘The rate-limited activation of N≡N triple bonds with high bond energies has been a bottleneck in photoctalytic nitrogen fixation.Here,polymeric carbon nitride with frustrated Lewis pairs(FLPs) was constructed by inserting electron-deficient magnesium into g-C_(3)N_(4)(CN).The synergistic interactions between Mg and amino groups in CN led to a 7.2 fold increase in the photoreactivity of nitrogen(N_(2)) fixation by carbon nitride.
文摘AIM:To evaluate the clinical outcomes of a new minimally invasive technique using horizontal mattress sutures and Hoffman pockets for four-point refixation of dislocated fourhaptic intraocular lenses(IOLs).METHODS:This retrospective consecutive case series included eyes with dislocated Akreos AO60 IOLs underwent scleral refixation using a horizontal mattress doubleneedle suture technique with intralamellar knot burial via Hoffman pockets.Clinical outcomes assessed included pre-and postoperative best-corrected visual acuity(BCVA),intraocular pressure(IOP),spherical equivalent(SE),suture duration,IOL centration,and perioperative complications.RESULTS:A total of 10 eyes from 10 patients(6 males)were included.The mean age at the time of IOL refixation was 53.10±13.07y(range:28-68y).The mean interval between initial IOL implantation and dislocation was 8.44±3.54y.The mean postoperative follow-up duration was 11.45±10.30mo.Surgical time averaged 15.3±1.77min,with no intraoperative complications.The mean axial length was 27.16±4.35 mm,with high myopia(HM)as the leading comorbidity(4/10 eyes).Postoperative BCVA significantly improved compared to preoperative values(P=0.025).Postoperative SE was significantly improved compared with preoperative(P=0.01).All IOLs remained centered throughout follow-up.CONCLUSION:This minimally invasive four-point scleral fixation technique offers a safe and effective refixation strategy for dislocated four-haptic IOLs.The horizontal mattress suture configuration combined with Hoffman pockets facilitates durable centration,avoids conjunctival dissection,and could be adopted into routine surgical practice.
基金financially supported by the National Natural Science Foundation of China(No.22172144 and 22272151)Key Research and Development Program of Zhejiang Province(2023C03148).
文摘Photocatalytic nitrogen fixation has emerged as a sustainable alternative for ammonia synthesis,playing a crucial role in alleviating energy shortages and environmental pollution.In this study,PbBiO_(2)Br was applied to photocatalytic nitrogen fixation for the first time,and its photocatalytic performance was effectively enhanced through Cu doping.The catalyst was synthesized via a simple reduction method,and its morphology,structure,and physicochemical properties were systematically investigated using various characterization techniques and density functional theory calculations.The results revealed that the incorporation of Cu2+partially replaced Pb2+,inducing lattice distortion in PbBiO_(2)Br,promoting the formation of oxygen vacancies,and modifying its electronic band structure.Specifically,Cu doping led to a slight bandgap narrowing,a reduction in work function,and a significant upward shift in the conduction band position.These changes enhanced light absorption,facilitated charge carrier migration and separation,and improved the reduction ability of photogenerated electrons.Moreover,Cu doping promoted N_(2)adsorption and activation.Consequently,the photocatalytic nitrogen fixation performance of Cu-doped PbBiO_(2)Br was significantly enhanced,achieving an optimal nitrogen fixation rate of 293μmol L^(−1)g^(−1)h^(−1),which is 3.6 times higher than that of pristine PbBiO_(2)Br.Additionally,Cu–PbBiO_(2)Br also showed good activity in the photocatalytic degradation of RhB,with a degradation rate 4.6 times higher than that of PbBiO_(2)Br.This work offers new insights into the application of PbBiO_(2)Br in photocatalytic nitrogen fixation and offers valuable guidance for the development of highly efficient nitrogen fixation materials in the future.
基金the National Key R&D Program of China(No.2021YFC2101604)National Natural Science Foundation of China(Nos.U23A20123,22278339)+1 种基金Fujian Provincial Key Science and Technology Program of China(No.2022YZ037013)Xiamen University for the financial support.
文摘Carbon dioxide(CO_(2))is the main greenhouse gas(GHG)released by human activities.The substitution of fossil resources by biomass as a bio-renewable resource,has significant potential to reduce GHG emissions.The approach to biomass,as the only true full-scale alternative to fossil resources,is progressing rapidly.Converting biomass into furanic compounds,as versatile platform chemicals for synthesizing a wide range of bio-based products is the cornerstone of sustainable technologies.The extensive body of this review combines the biomass valorization to furanic compounds by CO_(2)utilization and furanic compounds conversion by CO_(2)fixation.These processes can be strategically applied through both‘thermochemical’and‘electrochemical’pathways,by utilizing CO_(2)from the atmosphere or industrial emission point and returning it to the natural carbon cycle.In the thermochemical pathway CO_(2)acts as a carbon source(carboxylation and polymerization)or active reaction assistant in the biomass conversion(CO_(2)-assisted conversion),without altering its oxidation state,facilitating the synthesis of valuable products and polymers.Conversely,in the electrochemical pathway,CO_(2)can be used as a carbon source(electrocarboxylation)to give the corresponding carboxylic acid,or it can undergo reduction,yielding methanol,carbon monoxide(CO),formic acid,and analogous compounds,while on the other side,furanic compounds undergo oxidation yielding high-value-added chemicals.Finally,potential future research directions are suggested to promote CO_(2)utilization and fixation in the valorization of biomass-derived furanic compounds,and challenges facing further research are highlighted.
基金supported by the Natural Science Foundation of China (NSFC,No.52372212)。
文摘Photocatalysis uses solar energy to convert nitrogen and water directly into ammonia,helping reduce dependence on fossil fuels and offering a way to integrate the nitrogen cycle into a clean energy network.Ohmic junctions between metals and semiconductors have demonstrated significant advantages in enhancing stability and reducing carrier recombination,but their application in photocatalytic nitrogen fixation is limited due to the difficulty of work function matching and the complexity of fabrication processes.In this study,density functional theory(DFT) calculations were used to confirm the work function matching between Bi and Bi_(2)Ti_(2)O_(7)(BTO),ensuring the formation of an Ohmic junction.A Bi-Bi_(2)Ti_(2)O_(7)(B-BTO) composite was successfully synthesized via a one-step hydrothermal method,using bismuth nitrate and titanium sulfate as precursors.Compared to pure BTO,the B-BTO heterojunction,driven by dual electron injection from both metal Bi and BTO,significantly increased the ammonia synthesis rate to 686.95 μmol g^(-1)h^(-1),making it the most active nitrogen fixation material among similar pyrochlorebased catalysts to date.The differential charge density calculations,photocurrent(i-t) measurements,and photoluminescence(PL) tests further validate the role of Ohmic contacts in enhancing charge transfer and prolonging carrier lifetimes.This research provides valuable insight into the application of Ohmic junctions in photocatalytic nitrogen fixation and contributes to advancements in this field.
基金supported by the National Key R&D Program of China(No.2023YFC3709500).
文摘Global warming caused by the emission of CO_(2) in industrial flue gas has attractedmore and more attention.Therefore,to fix CO_(2) with high efficiency and environmentally friendly had become the hot research field.Compared with the traditional coal-fired power plant flue gas emission reduction technology,carbon fixation and emission reduction by microalgae is considered as a promising technology due to the advantages of simple process equipment,convenient operation and environmental protection.When the flue gas is treated by microalgae carbon fixation and emission reduction technology,microalgae cells can fix CO_(2) in the flue gas through photosynthesis,and simultaneously absorb NO_(x) and SO_(x) as nitrogen and sulfur sources required for growth.Meanwhile,they can also absorb mercury,selenium,arsenic,cadmium,lead and other heavy metal ions in the flue gas to obtain microalgae biomass.The obtained microalgae biomass can be further transformed into high valueadded products,which has broad development prospects.This paper reviews the mechanisms and pathways of CO_(2) sequestration,the mechanism and impacts of microalgal emission reduction of flue gas pollutants,and the applications of carbon sequestration in industrial flue gas by microalgae.Finally,this paper provides some guidelines and prospects for the research and application of green emission reduction technology for industrial flue gas.
基金supported by the Strategic Priority Research Program of the Chinese Academy of Sciences(Category B,XDB1090000).
文摘Plant synthetic biology has emerged as a transformative field in agriculture,offering innovative solutions to enhance food security,provide resilience to climate change,and transition to sustainable farming practices.By integrating advanced genetic tools,computational modeling,and systems biology,researchers can precisely modify plant genomes to enhance traits such as yield,stress tolerance,and nutrient use efficiency.The ability to design plants with specific characteristics tailored to diverse environmental conditions and agricultural needs holds great potential to address global food security challenges.Here,we highlight recent advancements and applications of plant synthetic biology in agriculture,focusing on key areas such as photosynthetic efficiency,nitrogen fixation,drought tolerance,pathogen resistance,nutrient use efficiency,biofortification,climate resilience,microbiology engineering,synthetic plant genomes,and the integration of artificial intelligence with synthetic biology.These innovations aim to maximize resource use efficiency,reduce reliance on external inputs,and mitigate environmental impacts associated with conventional agricultural practices.Despite challenges related to regulatory approval and public acceptance,the integration of synthetic biology in agriculture holds immense promise for creating more resilient and sustainable agricultural systems,contributing to global food security and environmental sustainability.Rigorous multi-field testing of these approaches will undoubtedly be required to ensure reproducibility.
基金financially supported by the National Natural Science Foundation of China(No.52174340)the National Key Research and Development Project of China(No.2022YFC2904505)the Hunan FURONG Scholars Project and the Basic Science Centre of the National Natural Science Foundation of China(No.72088101)。
文摘Potassium hydroxide(KOH)was introduced into the molybdenite roasting process to convert molybdenum(Mo)and sulfur(S)into water-soluble potassium molybdate(K_(2)MoO_(4))and potassium sulfate(K_(2)SO_(4)).Roasting with a 1.8-fold excess of KOH at 400℃ for 3 h enabled the leaching of over 99%of Mo from the molybdenum calcine using water.A precipitation method involving potassium–magnesium(K-Mg)salts was proposed for impurity removal.Under the conditions of pH 11,30℃,excess coefficient of 1.7 for Mg salts,and a duration of 1 h,98.37%of phosphorus(P)was removed from the K_(2)MoO_(4) solution.With post-purification,over 99%of Mo crystallized upon adjustment of pH to 1.Subsequently,S and K were recovered as K_(2)SO_(4) fertilizer from the crystalline mother liquor.An environmentally sustainable approach was proposed to conduct molybdenite production and ensure the efficient recovery of both Mo and S.
基金supported by the National Natural Science Foundation of China(Nos.51839011,42203079,and U2240208)the Carbon Peak/Neutralization Technology Innovation Project of Jiangsu Province,China(No.BK20220043)the Excellent Postdoctoral Project of Jiangsu Province,China(No.2022ZB452).
文摘Biological nitrogen fixation(BNF)is a crucial process that provides bioavailable nitrogen and supports primary production in freshwater lake ecosystems.However,the characteristics of diazotrophic community and nitrogenase activity in freshwater lake sediments remain poorly understood.Here,we investigated the diazotrophic communities and nitrogenase activities in the sediments of three large river-connected freshwater lakes in eastern China using 15N-isotope tracing and nifH sequencing.The sediments in these lakes contained diverse nitrogenase genes that were phylogenetically grouped into Clusters I and III.The diazotrophic communities in the sedimentswere dominated by stochastic processes in Hongze Lake and Taihu Lake,which had heterogeneous habitats and shallower water depths,while in Poyang Lake,which had deeper water and a shorter hydraulic retention time,the assembly of the diazotrophic community in the sediments was dominated by homogeneous selection processes.Temperature and water depth were also found the key environmental factors affecting the sediment diazotrophic communities.Sediment nitrogenase activities varied in the three lakes and within distinct regions of an individual lake,ranging from 0 to 14.58 nmol/(kg·hr).Nitrogenase activity was significantly correlated with ferric iron,total phosphorus,and organic matter contents.Our results suggested that freshwater lake sediment contain high diversity of nitrogen-fixing microorganisms with potential metabolic diversity,and the community assembly patterns and nitrogenase activities varied with the lake habitat.
基金supported by the National Key R&D Program of China under Project 2019YFA0705104GRF under Project CityU11212920.
文摘Electrochemical CO_(2)reduction has been considered a promising approach to neutralizing the global CO_(2)level.As an intriguing technique,metal-CO_(2)battery devices can not only capture CO_(2)into valuable carbonaceous chem-icals and reduce the CO_(2)concentration in the atmosphere but enable energy conversion.Among metal-CO_(2)batteries,aqueous Zn–CO_(2)batteries,especially rechargeable systems,exhibit flexible CO_(2)electrochemistry in terms of multi-carbon chemicals,which are gaseous or water-soluble,in favor of rechargeability and cycling durability of aqueous battery systems.Despite the increasing number of publications on Zn–CO_(2)batteries in the past three years,this field is still in its beginning stage and facing many challenges considering the capability of CO_(2)fixation and battery performance.Herein,we present a timely and overall summary of the recent progress in Zn–CO_(2)batteries,including fundamental mechanisms,affecting factors on electrochemical performance,catalyst cathodes,and electrolytes(catholytes and anolytes).Besides,we assess the application potential of Zn–CO_(2)batteries and compare this with those of alkali metal-CO_(2)batteries based on CO_(2)fixation and battery perfor-mance.Finally,we point out some current challenges for the further development of Zn–CO_(2)batteries and put forward perspectives of the research directions for practical applications of Zn–CO_(2)batteries in the future.
基金supported by the National Natural Science Foundation of China(52164028,52274297)the Start-up Research Foundation of Hainan University(KYQD(ZR)20008,KYQD(ZR)21125,KYQD(ZR)23169))+1 种基金Collaborative Innovation Center of Marine Science and Technology of Hainan University(XTCX2022HYC14)Innovative Research Project for Postgraduate Students in Hainan Province(Qhyb2024-95).
文摘Development of robust electrocatalyst for oxygen reduction reaction(ORR)in a seawater electrolyte is the key to realize seawater electrolyte-based zinc-air batteries(SZABs).Herein,constructing a local electric field coupled with chloride ions(Cl-)fixation strategy in dual single-atom catalysts(DSACs)was proposed,and the resultant catalyst delivered considerable ORR performance in a seawater electrolyte,with a high half-wave potential(E_(1/2))of 0.868 V and a good maximum power density(Pmax)of 182 mW·cm^(−2)in the assembled SZABs,much higher than those of the Pt/C catalyst(E_(1/2):0.846 V;Pmax:150 mW·cm^(−2)).The in-situ characterization and theoretical calculations revealed that the Fe sites have a higher Cl^(−)adsorption affinity than the Co sites,and preferentially adsorbs Cl^(−)in a seawater electrolyte during the ORR process,and thus constructs a low-concentration Cl^(−)local microenvironment through the common-ion exclusion effect,which prevents Cl^(−)adsorption and corrosion in the Co active centers,achieving impressive catalytic stability.In addition,the directional charge movement between Fe and Co atomic pairs establishes a local electric field,optimizing the adsorption energy of Co sites for oxygen-containing intermediates,and further improving the ORR activity.
基金supported by the National Natural Science Foundation of China(No.32160142)Guangxi Natural Science Foundation(No.2023GXNSFDA026034)+3 种基金State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources(SKLCUSAb202302)to H.W.,the National Natural Science Foundation of China(No.32460062)to Y.L.,and 1+9 Leading the Charge with Open Competition'project of Sichuan Academy of Agricultural Sciences(1+9KJGG010)Fruit tree breeding project in Sichuan Province(2021YFYZ0023)to H.X.
文摘Symbiotic nitrogen fixation in members of the Fabaceae family is highly efficient and beneficial for global agriculture,but not all species in this family form root nodules with rhizobial bacteria.Nodulation mainly occurs in plants belonging to the Papilionoideae and Caesalpinioideae subfamilies(Tederso0 et al.,2018;van Velzen et al.,2019).Nodulation mechanisms in Fabaceae are well studied(Yang et al.,2022),and genomic comparisons of nodulating and non-nodulating host species can provide valuable insights into the evolutionary and genetic basis of this key process.
