Grain size influences the yield and quality of rice(Oryza sativa L.),and grain length is one of the component traits of grain size.In this study,a near-isogenic line LB3 with long grain size was constructed using japo...Grain size influences the yield and quality of rice(Oryza sativa L.),and grain length is one of the component traits of grain size.In this study,a near-isogenic line LB3 with long grain size was constructed using japonica rice cultivar 02428,with short grain size,as the recipient parent and indica rice cultivar ZYX,with long grain size,as the donor parent,by multi-generation backcrossing and selfing.BSA-seq was used for preliminary QTL mapping and InDel markers were developed to fine map the locus.The major QTL,tentatively named qGL10,for grain length was located in a 128.45 kb region of chromosome 10.Combined with haplotype analysis of rice varieties,expression pattern analysis of candidate genes suggested LOC_Os10g39130(OsMADS56)as a candidate gene.Sequence alignment of OsMADS56 in 02428 and LB3 revealed that there were 15 SNPs in the promoter region and four in the coding region.Further haplotype analysis suggested that SNP9(G/A)located in the TGTCACA motif might account for the different expression levels of OsMADS56 in 02428 and LB3.These results lay a foundation for the application of qGL10 in molecular breeding of new rice varieties.展开更多
BACKGROUND Many studies have focused on the femoral tunnel technique and fixation method,but few studies have involved the tibial tunnel technique and fixation method.The all-inside technique is one of the new techniq...BACKGROUND Many studies have focused on the femoral tunnel technique and fixation method,but few studies have involved the tibial tunnel technique and fixation method.The all-inside technique is one of the new techniques that has been described in recent years.All-inside anterior cruciate ligament(ACL)reconstruction is based on a tibial socket instead of a full tunnel.This method has many potential advantages.AIM To compare clinical outcomes of knee ACL autograft reconstruction using allinside quadrupled semitendinosus(AIST)and traditional hamstring tendon(TBT)techniques.METHODS From January 2017 to October 2019,the clinical data of 80 patients with ACL reconstruction were retrospectively analyzed,including 67 males and 13 females.The patients had an average age of 24.3±3.1 years(age range:18-33 years).The AIST technique was used in 42 patients and the TBT technique was used in 38 patients.The time between operation and injury,operative duration,postoperative visual analogue scale(VAS)score and knee functional recovery were recorded and compared between the two groups.The International Knee Documentation Committee(IKDC)and Lysholm scoring system were used to comprehensively evaluate clinical efficacy.RESULTS Eighty patients were followed for 24-36 mo,with an average follow-up duration of 27.5±1.8 mo.There were no significant differences in the time between surgery and injury,operative duration,IKDC and Lysholm scores of the affected knee at the last follow-up evaluation between the two groups.There were significant differences in VAS scores 1 d,3 d,7 d,2 wk and 1 mo after surgery(P<0.05).There was no significant difference in VAS score at 3 mo,6 mo and 1 year after operation.CONCLUSION The efficacy of the AIST ACL reconstruction technique was comparable to the TBT technique,but the postoperative pain was less with the AIST technique.Thus,the AIST technique is an ideal treatment choice for ACL reconstruction.展开更多
Direct methanol fuel cells(DMFCs) have attracted extensive attention as promising next-generation energy conversion devices. However, commercialized proton exchange membranes(PEMs) hardly fulfill the demand of methano...Direct methanol fuel cells(DMFCs) have attracted extensive attention as promising next-generation energy conversion devices. However, commercialized proton exchange membranes(PEMs) hardly fulfill the demand of methanol tolerance for DMFCs employing high-concentration methanol solutions.Herein, we report a series of semi-crystalline poly(arylene ether ketone) PEMs with ultra-densely sulfonic-acid-functionalized pendants linked by flexible alkyl chains, namely, SL-SPEK-x(where x represents the molar ratio of the novel monomer containing multiple phenyl side chain to the bisfluoride monomers). The delicate structural design rendered SL-SPEK-x membranes with high crystallinity and well-defined nanoscale phase separation between hydrophilic and hydrophobic phases. The reinforcement from poly(ether ketone) crystals enabled membranes with inhibited dimensional variation and methanol penetration. Furthermore, microphase separation significantly enhanced proton conductivity. The SL-SPEK-12.5 membrane achieved the optimum trade-off between proton conductivity(0.182 S cm^(-1), 80 ℃), water swelling(13.6%, 80 ℃), and methanol permeability(1.6 × 10^(-7)cm~2 s^(-1)). The DMFC assembled by the SL-SPEK-12.5 membrane operated smoothly with a 10 M methanol solution, outputting a maximum power density of 158.3 mW cm^(-2), nearly twice that of Nafion 117(94.2 mW cm^(-2)). Overall, the novel structural optimization strategy provides the possibility of PEMs surviving in high-concentration methanol solutions, thus facilitating the miniaturization and portability of DMFC devices.展开更多
Gynostemma pentaphyllum(Thunb.)Makino is a perennial creeping herbaceous plant in the family Cucurbitaceae,which has great medicinal value and commercial potential,but urgent conservation efforts are needed due to the...Gynostemma pentaphyllum(Thunb.)Makino is a perennial creeping herbaceous plant in the family Cucurbitaceae,which has great medicinal value and commercial potential,but urgent conservation efforts are needed due to the gradual decreases and fragmented distribution of its wild populations.Here,we report the high-quality diploid chromosome-level genome of G.pentaphyllum obtained using a combination of next-generation sequencing short reads,Nanopore long reads,and Hi-C sequencing technologies.The genome is anchored to 11 pseudo-chromosomes with a total size of 608.95 Mb and 26588 predicted genes.Comparative genomic analyses indicate that G.pentaphyllum is estimated to have diverged from Momordica charantia 60.7 million years ago,with no recent whole-genome duplication event.Genomic population analyses based on genotyping-by-sequencing and ecological niche analyses indicated low genetic diversity but a strong population structure within the species,which could classify 32 G.pentaphyllum populations into three geographical groups shaped jointly by geographic and climate factors.Furthermore,comparative transcriptome analyses showed that the genes encoding enzyme involved in gypenoside biosynthesis had higher expression levels in the leaves and tendrils.Overall,the findings obtained in this study provide an effective molecular basis for further studies of demographic genetics,ecological adaption,and systematic evolution in Cucurbitaceae species,as well as contributing to molecular breeding,and the biosynthesis and biotransformation of gypenoside.展开更多
Our previous study revealed that intragastric administration of naringin improved remyelination in rats with spinal cord injury and promoted the recovery of neurological function of the injured spinal cord.This study ...Our previous study revealed that intragastric administration of naringin improved remyelination in rats with spinal cord injury and promoted the recovery of neurological function of the injured spinal cord.This study sought to reveal the mechanisms by which naringin improves oligodendrocyte precursor cell differentiation and maturation,and promotes remyelination.Spinal cord injury was induced in rats by the weight-drop method.Naringin was intragastrically administered daily(20,40 mg/kg) for 4 weeks after spinal cord injury induction.Behavioral assessment,histopathological staining,immunofluorescence spectroscopy,ultrastructural analysis and biochemical assays were employed.Naringin treatment remarkably mitigated demyelination in the white matter,increased the quality of myelinated nerve fibers and myelin sheath thickness,promoted oligodendrocyte precursor cell differentiation by upregulating the expression of NKx2.2 and 2′3′-cyclic nucleotide 3′-phosphodiesterase,and inhibited β-catenin expression and glycogen synthase kinase-3β(GSK-3β) phosphorylation.These findings indicate that naringin treatment regulates oligodendrocyte precursor cell differentiation and promotes remyelination after spinal cord injury through the β-catenin/GSK-3β signaling pathway.展开更多
[Objective] The aim was to construct the internal motivation of flued-cured tobacco natural aging. [Method] The variation of DNA copies of Bacillus megaterium, amylase activity, PPO, peroxydase and content of starch, ...[Objective] The aim was to construct the internal motivation of flued-cured tobacco natural aging. [Method] The variation of DNA copies of Bacillus megaterium, amylase activity, PPO, peroxydase and content of starch, neutro-protein, polyphenol in different aging period were investigated using Henan flue-cured tobacco leaves. [Result] Results showed that the DNA copies of Bacillus megaterium increased initially but decreased subsequently with the aging time. The DNA copies of Bacillus per gram of tobacco leaf surface reached the maximum number at 6 months aging. The activities of four enzymes showed the same variation trend as in DNA copies, and also reached the highest level at 6 months aging. Chemical ingredients, however, displayed a downward trend. The variation of enzyme activity and content of chemical composition were reflected in the changes of DNA copies in Bacillus megaterium. [Conclusion] The result indicate that Bacillus megaterium was the internal motivation of flue-cured tobacco natural aging.展开更多
A bistatic space debris observation system using a radio telescope as the receiving part is introduced.The detection capability of the system at different working frequencies is analyzed based on real instruments.The ...A bistatic space debris observation system using a radio telescope as the receiving part is introduced.The detection capability of the system at different working frequencies is analyzed based on real instruments.The detection range of targets with a fixed radar cross section and the detection ability of small space debris at a fixed range are discussed.The simulations of this particular observation system at different transmitting powers are also implemented and the detection capability is discussed.The simulated results approximately match the actual experiments.The analysis in this paper provides a theoretical basis for developing a space debris observation system that can be built in China.展开更多
Cenozoic tectonic evolution in the Tethyan region has greatly changed the landforms and environment of Eurasia,driving the evolution of animals and greatly affecting the diversity patterns of Eurasian animals.By combi...Cenozoic tectonic evolution in the Tethyan region has greatly changed the landforms and environment of Eurasia,driving the evolution of animals and greatly affecting the diversity patterns of Eurasian animals.By combining the latest Tethyan paleogeographic models and some recently published Eurasian zoological studies,we systematically summarize how tectonic evolution in the Tethyan region has influenced the evolution and diversity patterns of Eurasian animals.The convergence of continental plates,closure of Tethys Sea,and Tethyan sea-level changes have directly affected the composition and spatial distribution of Eurasian animal diversity.The topographic and environmental changes caused by Tethyan tectonics have determined regional animal diversity in Eurasia by influencing animal origin,dispersal,preservation,diversification,and extinction.The ecological transformations resulted in the emergence of new habitats and niches,which promoted animal adaptive evolution,specialization,speciation,and expansion.We highlight that the Cenozoic tectonic evolution of the Tethyan region has been responsible for much of the alteration in Eurasian animal distribution and has been an essential force in shaping organic evolution.Furthermore,we generalize a general pattern that Tethyan geological events are linked with Eurasian animal evolution and diversity dynamics.展开更多
Digital low-density parity-check(LDPC) decoders can hardly meet the power-limits brought by the new application scenarios. The analog LDPC decoder, which is an application of the analog computation technology, is cons...Digital low-density parity-check(LDPC) decoders can hardly meet the power-limits brought by the new application scenarios. The analog LDPC decoder, which is an application of the analog computation technology, is considered to have the potential to address this issue to some extent. However, due to the lack of automation tools and analog stopping criteria, the analog LDPC decoders suffer from costly handcraft design and additional decoding delay, and are not feasible to practical applications. To address these issues, a decoder architecture using reusable building blocks is designed to lower the handcraft design, and a probability stopping criterion that is specially designed for analog decoder is further planned and implemented to reduce the decoding delay. Then, a(480,240) CMOS analog LDPC decoder is designed and fabricated in a 0.35-μm CMOS technology. Experimental results show that the decoder prototype can achieve 50 Mbps throughput when the power consumption is about 86.3m W, and the decoding delay can be reduced by at most 93% compared with using the preset maximum decoding delay in existing works.展开更多
Low temperature prepared(La_(0.8)Sr_(0.2))_(0.9)MnO_3-δ-Y_(0.15)Zr_(0.85)O_(1.93)(LSM-YSZ) nano-composite cathode has high three-phase boundary(TPB) density and shows higher oxygen reduction reaction(ORR) activity th...Low temperature prepared(La_(0.8)Sr_(0.2))_(0.9)MnO_3-δ-Y_(0.15)Zr_(0.85)O_(1.93)(LSM-YSZ) nano-composite cathode has high three-phase boundary(TPB) density and shows higher oxygen reduction reaction(ORR) activity than traditional LSM-YSZ cathode at reduced temperatures. But the weak connection between cathode and electrolyte due to low sintering temperature restrains the performance of LSM-YSZ nano-composite cathode. A YSZ interlayer, consisted of nanoparticles smaller than 10 nm, is introduced by spinning coating hydrolyzed YSZ sol solution on electrolyte and sintering at 800 °C. The thickness of the interlayer is about 150 nm. The YSZ interlayer intimately adheres to the electrolyte and shows obvious agglomeration with LSM-YSZ nano-composite cathode. The power densities of the cell with interlayer are 0.83, 0.46 and 0.21 W/cm^2 under 0.7 V at 800, 700 and 600 °C, respectively, which are 36%, 48% and 50% improved than that of original cell. The interlayer introduction slightly increases the ohmic resistance but significantly decreases the polarization resistance. The depressed high frequency arcs of impedance spectra suggest that the oxygen incorporation kinetics are enhanced at the boundary of YSZ interlayer and LSM-YSZ nanocomposite cathode, contributing to improved electrochemical performance of the cell with interlayer.展开更多
Electrochemical conversion with solid oxide electrolysis cells is a promising technology for CO2 utilization and simultaneously store renewable energy.In this work,Ce0.9M0.1O2-δ(CeM,M=Fe,Co,Ni)catalysts are infiltrat...Electrochemical conversion with solid oxide electrolysis cells is a promising technology for CO2 utilization and simultaneously store renewable energy.In this work,Ce0.9M0.1O2-δ(CeM,M=Fe,Co,Ni)catalysts are infiltrated into La0.6Sr0.4Cr0.5Fe0.5O3-δ-Gd0.2Ce0.8O2-δ(LSCr Fe-GDC)cathode to enhance the electrochemical performance for CO2 electrolysis.CeCo-LSCrFe-GDC cell obtains the best performance with a current density of 0.652 A cm^-2,followed by CeFe-LSCrFe-GDC and CeNi-LSCrFe-GDC cells with the value of 0.603 and 0.535 A cm^-2,respectively,about 2.44,2.26 and 2.01 times higher than that of the LSCrFe-GDC cell at1.5 V and 800℃.Electrochemical impedance spectra combined with distributions of relaxed times analysis shows that both CO2 adsorption process and the dissociation of CO2 at triple phase boundaries are accelerated by Ce M catalysts,while the latter is the key rate-determining step.展开更多
A composite interlayer comprised of gadolinia doped ceria(GDC) and Co/Fe oxide was prepared and investigated for solid oxide electrolysis cell with yttrium stabilized zirconia(YSZ) electrolyte and La_(0.6)Sr_(0.4)Co_(...A composite interlayer comprised of gadolinia doped ceria(GDC) and Co/Fe oxide was prepared and investigated for solid oxide electrolysis cell with yttrium stabilized zirconia(YSZ) electrolyte and La_(0.6)Sr_(0.4)Co_(0.2)Fe_(0.8)O_(3-δ)(LSCF) anode. The interlayer was constructed of a base layer of GDC and a top layer of discrete Co_3O_4/FeCo_2O_4 particles. The presence of the GDC layer drastically alleviated the undesired reactions between LSCF and YSZ, and the presence of Co/Fe oxide led to further performance improvement. At 800 °C and 45% humidity, the cell with 70% Co/Fe-GDC interlayer achieved 0.98 A/cm^2 at 1.18 V, 14% higher than the cell without Co/Fe oxide. Electrochemical impedance spectroscopy(EIS) revealed that with higher Co/Fe content, both the ohmic resistance and the polarization resistance of the cell were reduced. It is suggested that Co/Fe oxide can react with the Sr species segregated from LSCF and Sr_(1-x)(Co,Fe)O_(3-δ), a compound with high catalytic activity and electronic conductivity. The Sr-capturing ability of Co/Fe oxide in combination with the Sr-blocking ability of GDC layer can effectively suppress the undesired reaction between LSCF and YSZ, and consequently improve the cell performance.展开更多
BACKGROUND Recurrent anterior shoulder instability is a common traumatic injury,the main clinical manifestation of which is recurrent anteroinferior dislocation of the humeral head.The current follow-up study showed t...BACKGROUND Recurrent anterior shoulder instability is a common traumatic injury,the main clinical manifestation of which is recurrent anteroinferior dislocation of the humeral head.The current follow-up study showed that the effect of arthroscopic Bankart repair is unreliable.AIM To evaluate the clinical efficacy of arthroscopy with subscapularis upper one-third tenodesis for treatment of anterior shoulder instability,and to develop a method to further improve anterior stability and reduce the recurrence rate.METHODS Between January 2015 and December 2018,male patients with recurrent anterior shoulder instability were selected.One hundred and twenty patients had a glenoid defect<20%and 80 patients had a glenoid defect>20%.The average age was 25 years(range,18–45 years).Patients with a glenoid defect<20%underwent arthroscopic Bankart repair with a subscapularis upper one-third tenodesis.The patients with a glenoid defect>20%underwent an arthroscopic iliac crest bone autograft with a subscapularis upper one-third tenodesis.All patients were assessed with Rowe and Constant scores.RESULTS The average shoulder forward flexion angle was 163.6°±8.3°and 171.8°±3.6°preoperatively and at the last follow-up evaluation,respectively.The average external rotation angle when abduction was 90°was 68.4°±13.6°and 88.5°±6.2°preoperatively and at the last follow-up evaluation,respectively.The mean Rowe scores preoperatively and at the last follow-up evaluation were 32.6±3.2 and 95.2±2.2,respectively(P<0.05).The mean Constant scores preoperatively and at the last follow-up evaluation were 75.4±3.5 and 95.8±3.3,respectively(P<0.05).No postoperative dislocations were recorded by the end of the follow-up period.CONCLUSION Arthroscopy with subscapularis upper one-third tenodesis was effective for treatment of recurrent anterior shoulder instability independent of the size of the glenoid bone defect,enhanced anterior stability of the shoulder,and did not affect postoperative range of motion of the affected limb.展开更多
Objective:China was the first country suffering from the SARS-CoV-2 pandemic and one of the countries with stringent mother-neonate isolation measure implemented.Now increasing evidence suggests that coronavirus disea...Objective:China was the first country suffering from the SARS-CoV-2 pandemic and one of the countries with stringent mother-neonate isolation measure implemented.Now increasing evidence suggests that coronavirus disease 2019(COVID-19)should not be taken as an indication for formula feeding or isolation of the infant from the mother.Methods:We conducted a retrospective cohort study in 44 hospitals from 14 provinces in China to investigate the management of neonates whose mothers have confirmed or suspected COVID-19.In addition,65 members of Chinese Neonatologist Association(CNA)were invited to give their comments and suggestions on the clinical management guidelines for high-risk neonates.Results:There were 121 neonates born to 118 mothers suspected with COVID-19 including 42 mothers with SARS-CoV-2 positive results and 76 mothers with SARS-CoV-2 negative results.All neonates were born by caesarean section,isolated from their mothers immediately after birth and were formula-fed.Five neonates were positive for SARSCoV-2 at initial testing between 36 and 46 h after birth.Regarding the confusion on the clinical management guidelines,58.78%of the newborns were put into isolation,32.22%were subject to PCR tests,and 5.16%and 2.75%received breastfeeding and vaccination,respectively.Conclusion:The clinical symptoms of neonates born to mothers with confirmed SARS-CoV-2 were mild,though five neonates might have been infected in utero or during delivery.Given the favorable outcomes of neonates born to COVID-confirmed mothers,full isolation may not be warranted.Rather,separation of the mother and her newborn should be assessed on a case-by-case basis,considering local facilities and risk factors for adverse outcomes,such as prematurity and fetal distress.展开更多
At present, China's local engineering universities have basically formed five modes of collaborative education between Engineering Universities and Enterprises, namely the mode relied on university-enterprise alli...At present, China's local engineering universities have basically formed five modes of collaborative education between Engineering Universities and Enterprises, namely the mode relied on university-enterprise alliance, the mode centered on the "Excellent Engineer Education and Training Program", the mode rooted in key disciplines, the mode based on the innovation and entrepreneurship education activities and the mode of carrying out international joint training, etc. However, in the process of university -enterprise collaborative education, there are still some shortcomings such as long-term deficiency, low fit and insufficient system. Therefore, three main ways to deepen the university-enterprise collaborative education are proposed: The first is to improve and implement the local government's policy guarantee system and incentive measures, fully mobilize and stimulate the enthusiasm and initiative of enterprises to participate in university -enterprise collaborative education;The second is to innovate the long-tenn operation mechanism of university-enterprise collaborative education, and to open up the last mile of educating and employing people;The third is to innovate the university-enterprise joint university-running mode and build a system of engineering talents that integrates innovation and practical capabilities.展开更多
Background Global connectivity and environmental change pose continuous threats to dengue invasions from worldwide to China.However,the intrinsic relationship on introduction and outbreak risks of dengue driven by the...Background Global connectivity and environmental change pose continuous threats to dengue invasions from worldwide to China.However,the intrinsic relationship on introduction and outbreak risks of dengue driven by the landscape features are still unknown.This study aimed to map the patterns on source-sink relation of dengue cases and assess the driving forces for dengue invasions in China.Methods We identified the local and imported cases(2006–2020)and assembled the datasets on environmental conditions.The vector auto-regression model was applied to detect the cross-relations of source-sink patterns.We selected the major environmental drivers via the Boruta algorithm to assess the driving forces in dengue outbreak dynamics by applying generalized additive models.We reconstructed the internal connections among imported cases,local cases,and external environmental drivers using the structural equation modeling.Results From 2006 to 2020,81,652 local dengue cases and 12,701 imported dengue cases in China were reported.The hotspots of dengue introductions and outbreaks were in southeast and southwest China,originating from South and Southeast Asia.Oversea-imported dengue cases,as the Granger-cause,were the initial driver of the dengue dynamic;the suitable local bio-socioecological environment is the fundamental factor for dengue epidemics.The Bio8[odds ratio(OR)=2.11,95%confidence interval(CI):1.67–2.68],Bio9(OR=291.62,95%CI:125.63–676.89),Bio15(OR=4.15,95%CI:3.30–5.24),normalized difference vegetation index in March(OR=1.27,95%CI:1.06–1.51)and July(OR=1.04,95%CI:1.00–1.07),and the imported cases are the major drivers of dengue local transmissions(OR=4.79,95%CI:4.34–5.28).The intermediary effect of an index on population and economic development to local cases via the path of imported cases was detected in the dengue dynamic system.Conclusions Dengue outbreaks in China are triggered by introductions of imported cases and boosted by landscape features and connectivity.Our research will contribute to developing nature-based solutions for dengue surveillance,mitigation,and control from a socio-ecological perspective based on invasion ecology theories to control and prevent future dengue invasion and localization.展开更多
基金supported by the Guangdong Provincial Key R&D Program(2021B0707010010)the Key R&D Program of Guangzhou Science and Technology Project(202103000083).
文摘Grain size influences the yield and quality of rice(Oryza sativa L.),and grain length is one of the component traits of grain size.In this study,a near-isogenic line LB3 with long grain size was constructed using japonica rice cultivar 02428,with short grain size,as the recipient parent and indica rice cultivar ZYX,with long grain size,as the donor parent,by multi-generation backcrossing and selfing.BSA-seq was used for preliminary QTL mapping and InDel markers were developed to fine map the locus.The major QTL,tentatively named qGL10,for grain length was located in a 128.45 kb region of chromosome 10.Combined with haplotype analysis of rice varieties,expression pattern analysis of candidate genes suggested LOC_Os10g39130(OsMADS56)as a candidate gene.Sequence alignment of OsMADS56 in 02428 and LB3 revealed that there were 15 SNPs in the promoter region and four in the coding region.Further haplotype analysis suggested that SNP9(G/A)located in the TGTCACA motif might account for the different expression levels of OsMADS56 in 02428 and LB3.These results lay a foundation for the application of qGL10 in molecular breeding of new rice varieties.
文摘BACKGROUND Many studies have focused on the femoral tunnel technique and fixation method,but few studies have involved the tibial tunnel technique and fixation method.The all-inside technique is one of the new techniques that has been described in recent years.All-inside anterior cruciate ligament(ACL)reconstruction is based on a tibial socket instead of a full tunnel.This method has many potential advantages.AIM To compare clinical outcomes of knee ACL autograft reconstruction using allinside quadrupled semitendinosus(AIST)and traditional hamstring tendon(TBT)techniques.METHODS From January 2017 to October 2019,the clinical data of 80 patients with ACL reconstruction were retrospectively analyzed,including 67 males and 13 females.The patients had an average age of 24.3±3.1 years(age range:18-33 years).The AIST technique was used in 42 patients and the TBT technique was used in 38 patients.The time between operation and injury,operative duration,postoperative visual analogue scale(VAS)score and knee functional recovery were recorded and compared between the two groups.The International Knee Documentation Committee(IKDC)and Lysholm scoring system were used to comprehensively evaluate clinical efficacy.RESULTS Eighty patients were followed for 24-36 mo,with an average follow-up duration of 27.5±1.8 mo.There were no significant differences in the time between surgery and injury,operative duration,IKDC and Lysholm scores of the affected knee at the last follow-up evaluation between the two groups.There were significant differences in VAS scores 1 d,3 d,7 d,2 wk and 1 mo after surgery(P<0.05).There was no significant difference in VAS score at 3 mo,6 mo and 1 year after operation.CONCLUSION The efficacy of the AIST ACL reconstruction technique was comparable to the TBT technique,but the postoperative pain was less with the AIST technique.Thus,the AIST technique is an ideal treatment choice for ACL reconstruction.
基金supported by the program of Jilin Provincial Department of Science and Technology (YDZJ202301ZYTS320)。
文摘Direct methanol fuel cells(DMFCs) have attracted extensive attention as promising next-generation energy conversion devices. However, commercialized proton exchange membranes(PEMs) hardly fulfill the demand of methanol tolerance for DMFCs employing high-concentration methanol solutions.Herein, we report a series of semi-crystalline poly(arylene ether ketone) PEMs with ultra-densely sulfonic-acid-functionalized pendants linked by flexible alkyl chains, namely, SL-SPEK-x(where x represents the molar ratio of the novel monomer containing multiple phenyl side chain to the bisfluoride monomers). The delicate structural design rendered SL-SPEK-x membranes with high crystallinity and well-defined nanoscale phase separation between hydrophilic and hydrophobic phases. The reinforcement from poly(ether ketone) crystals enabled membranes with inhibited dimensional variation and methanol penetration. Furthermore, microphase separation significantly enhanced proton conductivity. The SL-SPEK-12.5 membrane achieved the optimum trade-off between proton conductivity(0.182 S cm^(-1), 80 ℃), water swelling(13.6%, 80 ℃), and methanol permeability(1.6 × 10^(-7)cm~2 s^(-1)). The DMFC assembled by the SL-SPEK-12.5 membrane operated smoothly with a 10 M methanol solution, outputting a maximum power density of 158.3 mW cm^(-2), nearly twice that of Nafion 117(94.2 mW cm^(-2)). Overall, the novel structural optimization strategy provides the possibility of PEMs surviving in high-concentration methanol solutions, thus facilitating the miniaturization and portability of DMFC devices.
基金This study was supported by the National Natural Science Foundation of China(Nos.32000256,31900273,31770229,and 31270364)a Project funded by the China Postdoctoral Science Foundation(No.2020M673627XB)the Key Pro-gram of Research and Development of Shaanxi Province(No.2022ZDLSF06-02).
文摘Gynostemma pentaphyllum(Thunb.)Makino is a perennial creeping herbaceous plant in the family Cucurbitaceae,which has great medicinal value and commercial potential,but urgent conservation efforts are needed due to the gradual decreases and fragmented distribution of its wild populations.Here,we report the high-quality diploid chromosome-level genome of G.pentaphyllum obtained using a combination of next-generation sequencing short reads,Nanopore long reads,and Hi-C sequencing technologies.The genome is anchored to 11 pseudo-chromosomes with a total size of 608.95 Mb and 26588 predicted genes.Comparative genomic analyses indicate that G.pentaphyllum is estimated to have diverged from Momordica charantia 60.7 million years ago,with no recent whole-genome duplication event.Genomic population analyses based on genotyping-by-sequencing and ecological niche analyses indicated low genetic diversity but a strong population structure within the species,which could classify 32 G.pentaphyllum populations into three geographical groups shaped jointly by geographic and climate factors.Furthermore,comparative transcriptome analyses showed that the genes encoding enzyme involved in gypenoside biosynthesis had higher expression levels in the leaves and tendrils.Overall,the findings obtained in this study provide an effective molecular basis for further studies of demographic genetics,ecological adaption,and systematic evolution in Cucurbitaceae species,as well as contributing to molecular breeding,and the biosynthesis and biotransformation of gypenoside.
基金supported by the Natural Science Foundation of Beijing of China,No.7164317the Beijing Tsinghua Changgung Hospital Fund,No.12015C1028the National Natural Science Foundation of China,No.31400717
文摘Our previous study revealed that intragastric administration of naringin improved remyelination in rats with spinal cord injury and promoted the recovery of neurological function of the injured spinal cord.This study sought to reveal the mechanisms by which naringin improves oligodendrocyte precursor cell differentiation and maturation,and promotes remyelination.Spinal cord injury was induced in rats by the weight-drop method.Naringin was intragastrically administered daily(20,40 mg/kg) for 4 weeks after spinal cord injury induction.Behavioral assessment,histopathological staining,immunofluorescence spectroscopy,ultrastructural analysis and biochemical assays were employed.Naringin treatment remarkably mitigated demyelination in the white matter,increased the quality of myelinated nerve fibers and myelin sheath thickness,promoted oligodendrocyte precursor cell differentiation by upregulating the expression of NKx2.2 and 2′3′-cyclic nucleotide 3′-phosphodiesterase,and inhibited β-catenin expression and glycogen synthase kinase-3β(GSK-3β) phosphorylation.These findings indicate that naringin treatment regulates oligodendrocyte precursor cell differentiation and promotes remyelination after spinal cord injury through the β-catenin/GSK-3β signaling pathway.
文摘[Objective] The aim was to construct the internal motivation of flued-cured tobacco natural aging. [Method] The variation of DNA copies of Bacillus megaterium, amylase activity, PPO, peroxydase and content of starch, neutro-protein, polyphenol in different aging period were investigated using Henan flue-cured tobacco leaves. [Result] Results showed that the DNA copies of Bacillus megaterium increased initially but decreased subsequently with the aging time. The DNA copies of Bacillus per gram of tobacco leaf surface reached the maximum number at 6 months aging. The activities of four enzymes showed the same variation trend as in DNA copies, and also reached the highest level at 6 months aging. Chemical ingredients, however, displayed a downward trend. The variation of enzyme activity and content of chemical composition were reflected in the changes of DNA copies in Bacillus megaterium. [Conclusion] The result indicate that Bacillus megaterium was the internal motivation of flue-cured tobacco natural aging.
基金Supported by the National Natural Science Foundation of China
文摘A bistatic space debris observation system using a radio telescope as the receiving part is introduced.The detection capability of the system at different working frequencies is analyzed based on real instruments.The detection range of targets with a fixed radar cross section and the detection ability of small space debris at a fixed range are discussed.The simulations of this particular observation system at different transmitting powers are also implemented and the detection capability is discussed.The simulated results approximately match the actual experiments.The analysis in this paper provides a theoretical basis for developing a space debris observation system that can be built in China.
基金supported by the Strategic Priority Research Program of Chinese Academy of Sciences(XDB31000000)National Natural Sciences Foundation of China(32170447)program of Youth Innovation Promotion Association of Chinese Academy of Sciences(2019087)。
文摘Cenozoic tectonic evolution in the Tethyan region has greatly changed the landforms and environment of Eurasia,driving the evolution of animals and greatly affecting the diversity patterns of Eurasian animals.By combining the latest Tethyan paleogeographic models and some recently published Eurasian zoological studies,we systematically summarize how tectonic evolution in the Tethyan region has influenced the evolution and diversity patterns of Eurasian animals.The convergence of continental plates,closure of Tethys Sea,and Tethyan sea-level changes have directly affected the composition and spatial distribution of Eurasian animal diversity.The topographic and environmental changes caused by Tethyan tectonics have determined regional animal diversity in Eurasia by influencing animal origin,dispersal,preservation,diversification,and extinction.The ecological transformations resulted in the emergence of new habitats and niches,which promoted animal adaptive evolution,specialization,speciation,and expansion.We highlight that the Cenozoic tectonic evolution of the Tethyan region has been responsible for much of the alteration in Eurasian animal distribution and has been an essential force in shaping organic evolution.Furthermore,we generalize a general pattern that Tethyan geological events are linked with Eurasian animal evolution and diversity dynamics.
基金supported in part by the National Natural Science Foundation of China(No.61601027)the Opening Fund of the Space Objective Measure Key Laboratory(No.2016011)
文摘Digital low-density parity-check(LDPC) decoders can hardly meet the power-limits brought by the new application scenarios. The analog LDPC decoder, which is an application of the analog computation technology, is considered to have the potential to address this issue to some extent. However, due to the lack of automation tools and analog stopping criteria, the analog LDPC decoders suffer from costly handcraft design and additional decoding delay, and are not feasible to practical applications. To address these issues, a decoder architecture using reusable building blocks is designed to lower the handcraft design, and a probability stopping criterion that is specially designed for analog decoder is further planned and implemented to reduce the decoding delay. Then, a(480,240) CMOS analog LDPC decoder is designed and fabricated in a 0.35-μm CMOS technology. Experimental results show that the decoder prototype can achieve 50 Mbps throughput when the power consumption is about 86.3m W, and the decoding delay can be reduced by at most 93% compared with using the preset maximum decoding delay in existing works.
基金financial supports from the National Natural Science Foundation of China (No.21506208,21376238,21476230,91534128)DICP DMTO201405
文摘Low temperature prepared(La_(0.8)Sr_(0.2))_(0.9)MnO_3-δ-Y_(0.15)Zr_(0.85)O_(1.93)(LSM-YSZ) nano-composite cathode has high three-phase boundary(TPB) density and shows higher oxygen reduction reaction(ORR) activity than traditional LSM-YSZ cathode at reduced temperatures. But the weak connection between cathode and electrolyte due to low sintering temperature restrains the performance of LSM-YSZ nano-composite cathode. A YSZ interlayer, consisted of nanoparticles smaller than 10 nm, is introduced by spinning coating hydrolyzed YSZ sol solution on electrolyte and sintering at 800 °C. The thickness of the interlayer is about 150 nm. The YSZ interlayer intimately adheres to the electrolyte and shows obvious agglomeration with LSM-YSZ nano-composite cathode. The power densities of the cell with interlayer are 0.83, 0.46 and 0.21 W/cm^2 under 0.7 V at 800, 700 and 600 °C, respectively, which are 36%, 48% and 50% improved than that of original cell. The interlayer introduction slightly increases the ohmic resistance but significantly decreases the polarization resistance. The depressed high frequency arcs of impedance spectra suggest that the oxygen incorporation kinetics are enhanced at the boundary of YSZ interlayer and LSM-YSZ nanocomposite cathode, contributing to improved electrochemical performance of the cell with interlayer.
基金financially supported by the National Natural Science Foundation of China (Nos. 91534128, 21506208 and 21476230)the Ministry of Science and Technology of China (Grants 2016YFE0118300)the DNL Cooperation Fund, CAS (DNL180306)
文摘Electrochemical conversion with solid oxide electrolysis cells is a promising technology for CO2 utilization and simultaneously store renewable energy.In this work,Ce0.9M0.1O2-δ(CeM,M=Fe,Co,Ni)catalysts are infiltrated into La0.6Sr0.4Cr0.5Fe0.5O3-δ-Gd0.2Ce0.8O2-δ(LSCr Fe-GDC)cathode to enhance the electrochemical performance for CO2 electrolysis.CeCo-LSCrFe-GDC cell obtains the best performance with a current density of 0.652 A cm^-2,followed by CeFe-LSCrFe-GDC and CeNi-LSCrFe-GDC cells with the value of 0.603 and 0.535 A cm^-2,respectively,about 2.44,2.26 and 2.01 times higher than that of the LSCrFe-GDC cell at1.5 V and 800℃.Electrochemical impedance spectra combined with distributions of relaxed times analysis shows that both CO2 adsorption process and the dissociation of CO2 at triple phase boundaries are accelerated by Ce M catalysts,while the latter is the key rate-determining step.
基金supported by the National Natural Science Foundation of China (Nos. 21506208, 21476230 and 21376238)DICP DMTO201405
文摘A composite interlayer comprised of gadolinia doped ceria(GDC) and Co/Fe oxide was prepared and investigated for solid oxide electrolysis cell with yttrium stabilized zirconia(YSZ) electrolyte and La_(0.6)Sr_(0.4)Co_(0.2)Fe_(0.8)O_(3-δ)(LSCF) anode. The interlayer was constructed of a base layer of GDC and a top layer of discrete Co_3O_4/FeCo_2O_4 particles. The presence of the GDC layer drastically alleviated the undesired reactions between LSCF and YSZ, and the presence of Co/Fe oxide led to further performance improvement. At 800 °C and 45% humidity, the cell with 70% Co/Fe-GDC interlayer achieved 0.98 A/cm^2 at 1.18 V, 14% higher than the cell without Co/Fe oxide. Electrochemical impedance spectroscopy(EIS) revealed that with higher Co/Fe content, both the ohmic resistance and the polarization resistance of the cell were reduced. It is suggested that Co/Fe oxide can react with the Sr species segregated from LSCF and Sr_(1-x)(Co,Fe)O_(3-δ), a compound with high catalytic activity and electronic conductivity. The Sr-capturing ability of Co/Fe oxide in combination with the Sr-blocking ability of GDC layer can effectively suppress the undesired reaction between LSCF and YSZ, and consequently improve the cell performance.
文摘BACKGROUND Recurrent anterior shoulder instability is a common traumatic injury,the main clinical manifestation of which is recurrent anteroinferior dislocation of the humeral head.The current follow-up study showed that the effect of arthroscopic Bankart repair is unreliable.AIM To evaluate the clinical efficacy of arthroscopy with subscapularis upper one-third tenodesis for treatment of anterior shoulder instability,and to develop a method to further improve anterior stability and reduce the recurrence rate.METHODS Between January 2015 and December 2018,male patients with recurrent anterior shoulder instability were selected.One hundred and twenty patients had a glenoid defect<20%and 80 patients had a glenoid defect>20%.The average age was 25 years(range,18–45 years).Patients with a glenoid defect<20%underwent arthroscopic Bankart repair with a subscapularis upper one-third tenodesis.The patients with a glenoid defect>20%underwent an arthroscopic iliac crest bone autograft with a subscapularis upper one-third tenodesis.All patients were assessed with Rowe and Constant scores.RESULTS The average shoulder forward flexion angle was 163.6°±8.3°and 171.8°±3.6°preoperatively and at the last follow-up evaluation,respectively.The average external rotation angle when abduction was 90°was 68.4°±13.6°and 88.5°±6.2°preoperatively and at the last follow-up evaluation,respectively.The mean Rowe scores preoperatively and at the last follow-up evaluation were 32.6±3.2 and 95.2±2.2,respectively(P<0.05).The mean Constant scores preoperatively and at the last follow-up evaluation were 75.4±3.5 and 95.8±3.3,respectively(P<0.05).No postoperative dislocations were recorded by the end of the follow-up period.CONCLUSION Arthroscopy with subscapularis upper one-third tenodesis was effective for treatment of recurrent anterior shoulder instability independent of the size of the glenoid bone defect,enhanced anterior stability of the shoulder,and did not affect postoperative range of motion of the affected limb.
基金Funding from the Department of Maternal and Child Health,National Health Commission of the People's Republic of China:Construction and Evaluation of Neonatal Intensive Care System in China(201906063).
文摘Objective:China was the first country suffering from the SARS-CoV-2 pandemic and one of the countries with stringent mother-neonate isolation measure implemented.Now increasing evidence suggests that coronavirus disease 2019(COVID-19)should not be taken as an indication for formula feeding or isolation of the infant from the mother.Methods:We conducted a retrospective cohort study in 44 hospitals from 14 provinces in China to investigate the management of neonates whose mothers have confirmed or suspected COVID-19.In addition,65 members of Chinese Neonatologist Association(CNA)were invited to give their comments and suggestions on the clinical management guidelines for high-risk neonates.Results:There were 121 neonates born to 118 mothers suspected with COVID-19 including 42 mothers with SARS-CoV-2 positive results and 76 mothers with SARS-CoV-2 negative results.All neonates were born by caesarean section,isolated from their mothers immediately after birth and were formula-fed.Five neonates were positive for SARSCoV-2 at initial testing between 36 and 46 h after birth.Regarding the confusion on the clinical management guidelines,58.78%of the newborns were put into isolation,32.22%were subject to PCR tests,and 5.16%and 2.75%received breastfeeding and vaccination,respectively.Conclusion:The clinical symptoms of neonates born to mothers with confirmed SARS-CoV-2 were mild,though five neonates might have been infected in utero or during delivery.Given the favorable outcomes of neonates born to COVID-confirmed mothers,full isolation may not be warranted.Rather,separation of the mother and her newborn should be assessed on a case-by-case basis,considering local facilities and risk factors for adverse outcomes,such as prematurity and fetal distress.
文摘At present, China's local engineering universities have basically formed five modes of collaborative education between Engineering Universities and Enterprises, namely the mode relied on university-enterprise alliance, the mode centered on the "Excellent Engineer Education and Training Program", the mode rooted in key disciplines, the mode based on the innovation and entrepreneurship education activities and the mode of carrying out international joint training, etc. However, in the process of university -enterprise collaborative education, there are still some shortcomings such as long-term deficiency, low fit and insufficient system. Therefore, three main ways to deepen the university-enterprise collaborative education are proposed: The first is to improve and implement the local government's policy guarantee system and incentive measures, fully mobilize and stimulate the enthusiasm and initiative of enterprises to participate in university -enterprise collaborative education;The second is to innovate the long-tenn operation mechanism of university-enterprise collaborative education, and to open up the last mile of educating and employing people;The third is to innovate the university-enterprise joint university-running mode and build a system of engineering talents that integrates innovation and practical capabilities.
基金supported by the National Key Research and Development Program of China(2020YFC1200101)the National Natural Science Foundation of China(82073615,42041001).
文摘Background Global connectivity and environmental change pose continuous threats to dengue invasions from worldwide to China.However,the intrinsic relationship on introduction and outbreak risks of dengue driven by the landscape features are still unknown.This study aimed to map the patterns on source-sink relation of dengue cases and assess the driving forces for dengue invasions in China.Methods We identified the local and imported cases(2006–2020)and assembled the datasets on environmental conditions.The vector auto-regression model was applied to detect the cross-relations of source-sink patterns.We selected the major environmental drivers via the Boruta algorithm to assess the driving forces in dengue outbreak dynamics by applying generalized additive models.We reconstructed the internal connections among imported cases,local cases,and external environmental drivers using the structural equation modeling.Results From 2006 to 2020,81,652 local dengue cases and 12,701 imported dengue cases in China were reported.The hotspots of dengue introductions and outbreaks were in southeast and southwest China,originating from South and Southeast Asia.Oversea-imported dengue cases,as the Granger-cause,were the initial driver of the dengue dynamic;the suitable local bio-socioecological environment is the fundamental factor for dengue epidemics.The Bio8[odds ratio(OR)=2.11,95%confidence interval(CI):1.67–2.68],Bio9(OR=291.62,95%CI:125.63–676.89),Bio15(OR=4.15,95%CI:3.30–5.24),normalized difference vegetation index in March(OR=1.27,95%CI:1.06–1.51)and July(OR=1.04,95%CI:1.00–1.07),and the imported cases are the major drivers of dengue local transmissions(OR=4.79,95%CI:4.34–5.28).The intermediary effect of an index on population and economic development to local cases via the path of imported cases was detected in the dengue dynamic system.Conclusions Dengue outbreaks in China are triggered by introductions of imported cases and boosted by landscape features and connectivity.Our research will contribute to developing nature-based solutions for dengue surveillance,mitigation,and control from a socio-ecological perspective based on invasion ecology theories to control and prevent future dengue invasion and localization.
