Boson peak of glasses,a THz vibrational excess compared to Debye squared-frequency law,remains mysterious in condensed-matter physics and material science.It appears in many different kinds of glassy matters and is al...Boson peak of glasses,a THz vibrational excess compared to Debye squared-frequency law,remains mysterious in condensed-matter physics and material science.It appears in many different kinds of glassy matters and is also argued to exist in damped crystals.A consensus is that boson peak originates from the coupling of the(quasi)-localized non-phonon modes and the plane-wave-like phonon modes,but the coupling behavior is still not fully understood.In this paper,by modulating the content of localized modes and the frequencies of phonon modes,the coupling is clearly reflected in the localization and anharmonicity of low-frequency vibrational modes.The coupling enhances with increasing cooling rate and sample size.For finite sample size,phonon modes do not fully intrude into the low frequency to form a dense spectrum and they are not sufficiently coupled to the localized modes,thus there is no Debye level and boson peak is ill-defined.This suggestion remains valid in the presence of thermal motions induced by temperature,even though the anharmonicity comes into play.Our results point to the coupling of quasi-localized and phonon modes and its relation to the boson peak.展开更多
BACKGROUND Ulcerative colitis(UC)is an inflammatory condition with frequent relapse and recurrence.Evidence suggests the involvement of SLC6A14 in UC pathogenesis,but the central regulator remains unknown.AIM To explo...BACKGROUND Ulcerative colitis(UC)is an inflammatory condition with frequent relapse and recurrence.Evidence suggests the involvement of SLC6A14 in UC pathogenesis,but the central regulator remains unknown.AIM To explore the role of SLC6A14 in UC-associated pyroptosis.METHODS Quantitative real-time polymerase chain reaction(qRT-PCR),immunoblotting,and immunohistochemical were used to assess SLC6A14 in human UC tissues.Lipopolysaccharide(LPS)was used to induce inflammation in FHC and NCM460 cells and model enteritis,and SLC6A14 levels were assessed.Pyroptosis markers were quantified using enzyme-linked immunosorbent assay,Western blotting,and qRT-PCR,and EdU incubation,CCK-8 assays and flow cytometry were used to examine proliferation and apoptosis.Mouse models of UC were used for verification.RESULTS SLC6A14 was increased and correlated with NLRP3 in UC tissues.LPS-induced FHC and NCM460 cells showed increased SLC6A14 levels.Reducing SLC6A14 increased cell proliferation and suppressed apoptosis.Reducing SLC6A14 decreased pyroptosis-associated proteins(ASC,IL-1β,IL-18,NLRP3).NLRP3 overexpression counteracted the effects of sh-SLC6A14 on LPS-induced FHC and NCM460 cell pyroptosis.SLC6A14 improved the mucosa in mice with dextran sulfate sodium-induced colitis.CONCLUSION SLC6A14 promotes UC pyroptosis by regulating NLRP3,suggesting the therapeutic potential of modulating the SLC6A14/NLRP3 axis.展开更多
Flavonoids are important bioactive components in Dendrobium officinale,a medicinal orchid.They are involved in many biological activities,including protecting plants against biotic and abiotic stresses.Research on the...Flavonoids are important bioactive components in Dendrobium officinale,a medicinal orchid.They are involved in many biological activities,including protecting plants against biotic and abiotic stresses.Research on the key genes related to flavonoid biosynthesis in D.officinale is limited.In this study,one of the key flavonoid biosynthesis genes,flavanone 3-hydroxylase(F3H),was characterized from D.officinale.The open reading frame of DoF3H was 1134 bp long and it encoded a 377-amino acid protein.The DoF3H protein showed considerably high homology with F3H proteins from other plant species and shared a common evolutionary ancestor with other F3Hs.DoF3H transcripts were detected in different organs of adult plants and mainly accumulated in flowers,followed by roots,stems and leaves,a pattern that was similar to the content of flavonoids.Recombinant DoF3H protein,which was localized in the cytosol,could convert naringenin to dihydrokaempferol.The mRNA levels of DoF3H were significantly induced by salt and cold stresses.Furthermore,the heterologous expression of DoF3H in Escherichia coli conferred it higher tolerance to salt and cold stresses.These results provide insight into the molecular function of DoF3H in the biosynthesis of flavonoids,and provide a new application for improvement of abiotic tolerance in D.officinale.展开更多
目的讨论老年冠状动脉搭桥术后平均动脉压与急性肾损伤的关系。方法选择250例行体外循环下冠状动脉搭桥的老年患者,根据术后平均动脉压分为4组:66~70 mm Hg组、71~75 mm Hg组、76~80 mm Hg、≥81 mm Hg组,回顾性比较各组的术后6 h乳酸...目的讨论老年冠状动脉搭桥术后平均动脉压与急性肾损伤的关系。方法选择250例行体外循环下冠状动脉搭桥的老年患者,根据术后平均动脉压分为4组:66~70 mm Hg组、71~75 mm Hg组、76~80 mm Hg、≥81 mm Hg组,回顾性比较各组的术后6 h乳酸清除率、急性肾损伤发生率、住重症监护室(ICU)时间、30 d死亡率。结果 4组患者间术后急性肾损伤发生率及30 d死亡率比较,差异无统计学意义(P>0.05)。平均动脉压71~75 mm Hg组较其他3组患者的术后6 h乳酸清除率高、住ICU时间短,差异有统计学意义(P<0.05)。结论老年冠状动脉搭桥术后进一步提高高于65 mm Hg的平均动脉压并不能减少急性肾损伤的发生率。展开更多
In deep underground engineering,understanding of time-related stress memory properties is critical to evaluate the in situ stress conditions of a rock mass.In this study,the time-sensitivity mechanism of the rock stre...In deep underground engineering,understanding of time-related stress memory properties is critical to evaluate the in situ stress conditions of a rock mass.In this study,the time-sensitivity mechanism of the rock stress memory properties under tensile stress was investigated.It was found that the material property(Poisson’s ratio)and crack angle were the controlling factors of the Kaiser effect(KE)under tensile stress.In particular,the time-sensitivity of the stress memory properties was closely related to the crack growth path.When the failure of the rock specimen was dominated by tensile microcracks and the crack development direction was deflected by up to 30°in the successive loading process,the stress memory capacity was likely to be time-independent for a sandstone specimen.The distribution of the Felicity ratio in a Brazilian test was more discrete than that in a three-point bending test It also showed that the changes in the crack path,rather than the time interval between successive loading cycles,led to inaccuracy of the detected KE.This study provides insights into stress memory-related issues under uniaxial or more complex stress conditions and thus facilitates development of methods for testing in situ mechanical behaviors of rocks with acoustic emission(AE)technology.展开更多
Objective:To observe the effects of resveratrol on myocardial cell injury and Mst1/Sirt3 signaling pathway mediated autophagy in type 2 diabetic mice. Methods:C57 BL/KSJ db/db mice were allocated to the normal control...Objective:To observe the effects of resveratrol on myocardial cell injury and Mst1/Sirt3 signaling pathway mediated autophagy in type 2 diabetic mice. Methods:C57 BL/KSJ db/db mice were allocated to the normal control group,the model group,and the resveratrol group;C57 BL/KSJ db/m mice served as the melbine group,with 10 mice each. The resveratrol group and the melbine group were treated with resveratrol and metformin by gavage,respectively. The normal control group and the model group were treated with equal volume of normal saline by gavage,for 8 consecutive weeks. H & E staining,transmission electron microscopy and immunofluorescence were used to observe the pathological morphology,ultrastructure and apoptosis levels of myocardial tissues,respectively. RT-qPCR method was used to detect the expression levels of apoptosis genes Bax and Bcl-2 in myocardial tissues,and Western-blot method was used to detect the expression levels of autophagy proteins(LC3 and p62),Mst1 and Sirt3 proteins in myocardial tissue. Results:Compared with the model group,resveratrol can significantly reduce the body weight,blood glucose level and serum CK and LDH levels of db/db mice,and the differences were statistically significant(P<0.05;P<0.01). Meanwhile,after resveratrol treatment,myocardial inflammation score,apoptosis rate,Bax mRNA expression level and Bax/Bcl-2 ratio in myocardial tissue were significantly reduced,and Bcl-2 mRNA expression level was significantly increased,and the differences were statistically significant(P<0.01). In addition,compared with the model group,the expression level of p62 and p-Mst1 protein in the myocardial tissue of the resveratrol group was significantly reduced,and the expression level of Sirt3 protein and the ratio of LC3Ⅱ/LC3Ⅰ were significantly increased,and the differences were statistically significant(P<0.01). Conclusion:Resveratrol promotes the autophagy level of cardiomyocytes by activating the Mst1/Sirt3 signaling pathway and inhibits cardiomyocyte apoptosis to play a protective role in diabetic cardiomyopathy.展开更多
Objective:To observe the clinical effect of electroacupuncture"Tongmin point"combined with heat-sensitive moxibustion on knee osteoarthritis and its effect on blood lipid level,polyprotein polysaccharide enz...Objective:To observe the clinical effect of electroacupuncture"Tongmin point"combined with heat-sensitive moxibustion on knee osteoarthritis and its effect on blood lipid level,polyprotein polysaccharide enzyme-4(a disintegrin and metalloprotease with thrombospondin motifs,ADAMTS-4,matrix metalloproteinase-3(matrix metalloproteinase-3,);and MMPs-3)Impact.Methods:80 patients were randomly divided into two groups,40 cases per group,Treatment and control groups,The treatment group was given electroacupuncture combined with heat-sensitive moxibustion,Six times a week,Continuous treatment for 4 weeks;The control group was given intraarticular sodium hyaluronate,Once a week,continuous treatment for 4 weeks.Results:During the treatment period,Visual analogue scale visual analogue scale,VAS)show a downward trend,Intra-group comparisons,Differences were statistically significant(P<0.05);After 2 weeks of treatment,4 weeks of treatment and 2 weeks of follow-up,All the scores in the treatment group were lower than those in the control group(P<0.05).After treatment in two groups(The Western Ontario and Mc Master Universities Osteoarthritis Index,)of osteoarthritis index,University of Western Ontario WOMAC)The scores of each item decreased significantly,treatment group was better than the control group(P<0.05).After four weeks of treatment,(Total cholesterol,)Total cholesterol TC,triglycerides(Triglyceride,);and TG,LDL(Low density lipoprotein,);and LDL-C)A decrease in content,High density lipoprotein High density lipoprotein,HDL-C)Increased content,and the improvement was better than that of the control group(P<0.05).After treatment,the ADAMTS-4,MMPs-3 content decreased,Intergroup comparisons,Differences were statistically significant(P<0.05);The effective rate in the treatment group was 87.5%,The control rate was 60%,treatment group was more effective(P<0.05).Conclusions:Electroacupuncture"Tongmin point"combined with heat-sensitive moxibustion can obviously improve the symptoms of knee osteoarthritis patients,Regulate blood lipids,High security,It is worth popularizing in clinic.展开更多
Objective:To observe the expression of CTX-I(Ⅰcollagen C-terminal foreign body peptide)and TRACP(tartrate-resistant acid phosphatase)in different syndromes of knee osteoarthritis and their correlation with ADAMTS-4(p...Objective:To observe the expression of CTX-I(Ⅰcollagen C-terminal foreign body peptide)and TRACP(tartrate-resistant acid phosphatase)in different syndromes of knee osteoarthritis and their correlation with ADAMTS-4(polyproteoglycan enzyme-4)and MMPS-3(matrix metalloproteinase-3).Methods:A total of 98 patients diagnosed with knee osteoarthritis were enrolled from the Rehabilitation Pain Department and Rheumatology Department of Wuhan Caidian District People's Hospital.According to their syndrome types,they were divided into 40 cases of Yang deficiency and cold constipation type,28 cases of qi stagnation and blood stasis type,and 30 cases of kidney jing deficiency type.The contents of bone metabolism indexes,ADAMTS-4 and MMPS-3 in different syndromes of the three groups were compared.Correlation of bone metabolism indexes with ADAMTS-4 and MMPS-3.Results:There were statistically significant differences in the contents of CTX-I,TRACP,ADAMTS-4 and MMPS-3 among three groups with different syndromes(P<0.05).There was a positive correlation between CTX-I,TRACP,ADAMTS-4 and MMPS-3(P<0.05).The syndrome of qi stagnation and blood stasis was positively correlated with TRACP and ADAMTS-4,and negatively correlated with MMPS-3(P<0.05).The renal essence deficiency syndrome was positively correlated with CTX-I,ADAMTS-4 and MMPS-3(P<0.05).Bone metabolic indexes(CTX-I,TRACP)were positively correlated with ADAMTS-4 and MMPS-3(P<0.05).Conclusion:Different syndromes of knee osteoarthritis are correlated with bone metabolism indexes,ADAMTS-4 and MMPS-3,which can provide a certain objective basis for clinical TCM syndrome differentiation and classification。展开更多
Physical aging is an inherent property of glassy matter, but understanding its microscopic mechanism remains a challenge particularly at the particle level. In this work, we use a confocal microscope to in-situ trace ...Physical aging is an inherent property of glassy matter, but understanding its microscopic mechanism remains a challenge particularly at the particle level. In this work, we use a confocal microscope to in-situ trace the particle trajectories in a 3D colloidal glass for 73000 s, aiming at resolving the aging dynamics. By calculating the mean square displacement of particle motions, we find that the glass aging with time can be divided into three stages: β relaxation, α relaxation and free diffusion. The system's mean square displacement at each aging state is quantitatively resolved into three contributions of particle dynamics modes: vibration within the nearest-neighbor cages, hopping between cages and cooperative rearrangement. We further calculate the particle's free volume and find that the β-to-α transition is accompanied by the temporary increase of the system-averaged free volume due to pronounced hops of particles. Nevertheless, the temporal autocorrelation of the free volume spatial distribution still obeys a monotonically stretched exponential decay with an exponent of 0.76, which is related to the sub-diffusion dynamics of cooperative rearrangements and hops mixed in α relaxation. According to the resolved vibrational displacements,we calculate the vibrational density of states of this 3D glass, and the characteristic boson peak is reproduced at low frequencies.Our findings shed insight into the particle-level aging dynamics of a real glass under purely thermal activation.展开更多
Recently,there has been growing interest in knowing the best hygrometry level during high-flow nasal oxygen and non-invasive ventilation(NIV)and its potential influence on the outcome.Various studies have shown that b...Recently,there has been growing interest in knowing the best hygrometry level during high-flow nasal oxygen and non-invasive ventilation(NIV)and its potential influence on the outcome.Various studies have shown that breathing cold and dry air results in excessive water loss by nasal mucosa,reduced mucociliary clearance,in-creased airway resistance,reduced epithelial cell function,increased inflammation,sloughing of tracheal epithe-lium,and submucosal inflammation.With the Coronavirus Disease 2019 pandemic,using high-flow nasal oxygen with a heated humidifier has become an emerging form of non-invasive support among clinicians.However,we cannot always assume stable humidification.Similarly,there are no clear guidelines for using humidification dur-ing NIV,although humidification of inspired gas during invasive ventilation is an accepted standard of care.NIV disturbs the normal physiological system that warms and humidifies inspired gases.If NIV is supplied through an intensive care unit ventilator that utilizes anhydrous gases from compressed wall air and oxygen,the risk of dry-ness increases.In addition,patients with acute respiratory failure tend to breathe through the mouth during NIV,which is a less efficient route than nasal breathing for adding heat and moisture to the inspired gas.Obstructive sleep apnea syndrome is one of the most important indications for chronic use of NIV at home.Available data suggest that up to 60%of patients with obstructive sleep apnea syndrome who use continuous positive airway pressure therapy experience nasal congestion and dryness of the mouth and nose.Therefore,humidifying the inspired gas in NIV may be essential for patient comfort and compliance with treatment.We aimed to review the available bench and clinical studies that addressed the utility of hygrometry in NIV and nasal high-flow oxygen and discuss the technical limitations of different humidification systems for both systems.展开更多
Water pollution has become a serious problem owing to the development of society.Photocatalysis is a promising approach to remove various pollutants in water,such as organic pollutants and antibiotic resistance bacter...Water pollution has become a serious problem owing to the development of society.Photocatalysis is a promising approach to remove various pollutants in water,such as organic pollutants and antibiotic resistance bacteria.Meanwhile,the design of heterojunction between two semiconductors is an effective path to improve photocatalytic properties due to its potential in improving separation and transfer of photoinduced carriers.In this study,Nb_(2)O_(5)/g-C_(3)N_(4)(NO/CN)composite materials were prepared through a one-step heating method.Characterizations confirmed successful preparation of NO/CN heterojunction structure and better optical properties than pure g-C_(3)N_(4) and Nb_(2)O_(5).NO/CN composite materials showed excellent photocatalytic efficiency for Escherichia coli(E.coli)inactivation(95%)compared with the pure Nb_(2)O_(5)(10%) and g-C_(3)N_(4)(77%).Meanwhile,NO/CN exhibited better organic pollutants removal(Rh B for94%,methyl orange(MO)for 15%and methylene blue(MB)for 87%)under visible light,which is likely owing to the heterojunction structure between g-C_(3)N_(4) and Nb_(2)O_(5) that leads to the good separation of photogenerated electron-hole pair.Free radical scavenging and electron spin resonance(ESR)experiments demonstrated that superoxide radicals(·O_(2)^(-)) and holes(h^(+)) were the dominant radicals.Therefore,the NO/CN was proposed to be a promising material for effective disinfection and removal of organic contaminants in water treatment.展开更多
Accurate monitoring of the atmospheric environment and its evolution are important for understanding the sources,chemical mechanisms,and transport processes of air pollution and carbon emissions in China,and for regul...Accurate monitoring of the atmospheric environment and its evolution are important for understanding the sources,chemical mechanisms,and transport processes of air pollution and carbon emissions in China,and for regulatory and control purposes.This study gives an overview of atmospheric environment monitoring technology and equipment in China and summarizes the major achievements obtained in recent years.China has made great progress in the development of atmospheric environment monitoring technology and equipment with decades of effort.The manufacturing level of atmospheric environment monitoring equipment and the quality of products have steadily improved,and a technical&production system that can meet the requirements of routine monitoring activities has been initiated.It is expected that domestic atmospheric environment monitoring technology and equipment will be able to meet future demands for routine monitoring activities in China and provide scientific assistance for addressing air pollution problems.展开更多
Abrupt air pollution accidents can endanger people’s health and destroy the local ecological environment.The appropriate emergency response can minimize the harmful effects of accidents and protect people’s lives an...Abrupt air pollution accidents can endanger people’s health and destroy the local ecological environment.The appropriate emergency response can minimize the harmful effects of accidents and protect people’s lives and property.This paper provides an overview of the key emergency response technologies for abrupt air pollution accidents around the globe with emphasis on the major achievements that China has obtained in recent years.With decades of effort,China has made significant progress in emergency monitoring technologies and equipment,source estimation technologies,pollutant dispersion simulation technologies and others.Many effective domestic emergency monitoring instruments(e.g.,portable DOAS/FT-IR systems,portable FID/PID systems,portable GC-MS systems,scanning imaging remote sensing systems,and emergency monitoring vehicles)had been developed which can meet the demands for routine emergency response activities.A monitoring layout technique combining air dispersion simulation,fuzzy comprehensive evaluation,and a post-optimality analysis was proposed to identify the optimal monitoring layout scheme under the constraints of limited monitoring resources.Multiple source estimation technologies,including the forward method and the inversion method,have been established and evaluated under various scenarios.Multi-scale dynamic pollution dispersion simulation systems with high temporal and spatial resolution were further developed.A comprehensive emergency response platform integrating database support,source estimation,monitoring schemes,fast monitoring of pollutants,pollution predictions and risk assessment was developed based on the technical idea of"source identification-model simulation-environmental monitoring"dynamic interactive feedback.It is expected that the emergency response capability for abrupt air pollution accidents will gradually improve in China.展开更多
Orchid plants develop protocorms upon germination and produce protocorm-like structures called protocorm-like bodies(PLBs)from protocorms and somatic cells via tissue culture.Protocorm-like bodies have broad technical...Orchid plants develop protocorms upon germination and produce protocorm-like structures called protocorm-like bodies(PLBs)from protocorms and somatic cells via tissue culture.Protocorm-like bodies have broad technical application potential in the orchid industry and their regeneration is a distinct developmental process in the plant kingdom.However,little is known about this unparalleled developmental program.In this study,we identified a PLB-abundant gene,ethylene response factor(ERF),and a transcription factor named Do ERF5,and determined its important role in PLB regeneration in Dendrobium orchid.Overexpression of Do ERF5 in Dendrobium greatly enhanced the PLB regeneration from PLB and stem explants,and upregulated the expression of WOUND-INDUCED DEDIFFERENTIATION(Do WIND)homologs and SHOOT MERISTEMLESS(Do STM),as well as the genes involved in cytokinin biosynthesis(Do IPT)and the cytokinin response factors(Do ARRs).However,silencing Do ERF5 reduced the regeneration rate of PLBs,and downregulated the expression of Do WIND homologs,Do STM and Do ARRs.We demonstrated that Do ERF5 is directly bound to the Do STM promoter and regulates its expression.In addition,overexpression of Do STM in Dendrobium orchid resulted in favorable regeneration of PLBs.Our results clarify that Do ERF5 regulates the regeneration of PLB by enhancing Do STM expression.Our findings provide new insights into how Do ERF5 mediates PLB regeneration and offers technical potential in improving clonal propagation,preservation,and the bioengineering of orchids.展开更多
Gene expression quantification at mRNA level is very important for postgenomic studies, as gene expression level is the reflection of the special biological function of the target gene. Methods used for gene expressio...Gene expression quantification at mRNA level is very important for postgenomic studies, as gene expression level is the reflection of the special biological function of the target gene. Methods used for gene expression quantification, such as microarray or quantitative real-time polymerase chain reaction （qRT-PCR）, require stable expressed reference genes. Thus, finding suitable control genes is essential for gene quantification. In this study, a genome-wide survey of reference genes during metamorphism was performed on silkworm Bombyx mori. Twelve genes were chosen as putative reference genes based on a whole genome oligonucleotide microarray normalized by external controls. Then, qRT- PCR was employed for further validation and selection of potential reference gene candidates. The results were analyzed, and stable genes were selected using geNorm 3.4 and NormFinder software. Finally, considering factors from every aspect, translation initiation factor 4A, translation initiation factor 3 subunit 4, and translation initiation factor 3 subunit 5 （represented by sw22934, sw14876, and sw13956） were selected as reliable internal controls across the examined developmental stages, while cytoplasmic actin （sw22671）, the commonly used reference gene in a previous study was shown to vary drastically throughout the examined developmental stages. For future research, we recommend the use of the geometric mean of those three stable reference genes as an accurate normalization factor for data normalization of different developmental stages during metamorphism.展开更多
Reductive immobilization of radioactive pertechnetate(99TcO4^-) in simulated groundwater was studied by prepared carboxymethyl cellulose(CMC) and starch stabilized zero valent iron nanoparticles(nZVI),and long-term re...Reductive immobilization of radioactive pertechnetate(99TcO4^-) in simulated groundwater was studied by prepared carboxymethyl cellulose(CMC) and starch stabilized zero valent iron nanoparticles(nZVI),and long-term remobilization of reduced Tc was also evaluated under anoxic and oxic conditions.The stabilized nZVI can effectively reduce soluble 99Tc(Ⅶ) to insoluble 99 Tc(Ⅳ),and they can be easily delivered into a contaminated groundwater zone and facilitate in situ remediation.In this study,CMCstabilized nZVI showed higher reactivity than that using starch as the stabilizer.Batch experiments indicated that more than 99% of 99 Tc(Ⅶ)(CO=12 mg/mL) was reduced and removed from groundwater by CMC-stabilized nZVI with a CMC content of 0.2%(w/w) at a broad pH of 5-8.X-ray diffraction(XRD)and X-ray photoelectron spectroscopy(XPS) analyses further confirmed that 99Tc(Ⅶ)O4^-transformed into 99Tc(Ⅳ)O2(s).The presence of bicarbonate exhibited insignificant effect on Tc immobilization,while humic acid(HA) inhibited reaction mainly due to retardation on electron transfer and formation of Tc(IV)-HA complexes.More interesting,the immobilized Tc(Ⅳ) remained insoluble even after 120 d under anoxic condition,while only^21 % was remobilized when exposed to air.Therefore,biomacromolecules stabilized nZVI nanoparticles could be a viable alternative for in situ remediation of radioactive contamination in groundwater.展开更多
Peracetic acid(PAA)-based system is becoming an emerging advanced oxidation process(AOP)for effective removal of organic contaminants from water.Various approaches have been tested to activate PAA,while no previous re...Peracetic acid(PAA)-based system is becoming an emerging advanced oxidation process(AOP)for effective removal of organic contaminants from water.Various approaches have been tested to activate PAA,while no previous researches reported the application of metal-organic frameworks(MOFs)materials for PAA activation.In this study,zeolitic imidazole framework(ZIF)-67,a representative MOFs,was facile synthesized via direct-mixing method at room temperature,and tested for PAA activation and sulfachloropyridazine(SCP)degradation.The as-synthesized ZIF-67 exhibited excellent performance for PAA activation and SCP degradation with 100%of SCP degraded within 3 min,owing to the specific MOFs structure and abundant Co^(2+) sites.The pseudo-first-order kinetic model was applied to fit the kinetic data,with rate constant k_(1) of ZIF-67 activated PAA system 34.2 and 156.5 times higher than those of conventional Co_(3)O_(4)activated PAA and direct oxidation by PAA.Radical quenching experiments and electron paramagnetic resonance(EPR)analysis indicated that CH_(3)C(O)OO^(·)played a major role in this PAA activation system.Then,the Fukui index based on density functional theory(DFT)calculation was used to predict the possible reaction sites of SCP for electrophilic attack by CH_(3)C(O)OO^(·).In addition,the degradation pathway of SCP was proposed based on Fukui index values and intermediates detection,which mainly included the S-N bond cleavage and SO_(2)extrusion and followed by further oxidation,dechlorination,and hydroxylation.Therefore,ZIF-67 activated PAA is a novel strategy and holds strong potential for the removal of emerging organic contaminants(EOCs)from water.展开更多
Introduction Pneumonia caused by a novel coronavirus known as 2019 novel coronavirus disease(COVID-19)[1]appeared in Wuhan,China in December 2019,and approximately 15%to 30%of patients developed acute respiratory dist...Introduction Pneumonia caused by a novel coronavirus known as 2019 novel coronavirus disease(COVID-19)[1]appeared in Wuhan,China in December 2019,and approximately 15%to 30%of patients developed acute respiratory distress syndrome within a short period of time.[2,3]To reduce respiratory symptoms and improve prognosis,respiratory support is the most important means of life support,[1]and non-invasive respiratory support systems,[2]including various conventional oxygen therapies,non-invasive positive pressure ventilation(NPPV),and high-flow nasal cannula(HFNC),are most commonly used.However,their efficacy and safety remain unclear,and whether they increase the risk of aerosol dispersion and disease transmission is particularly controversial.[4,5]Given that there are many similarities between COVID-19 pneumonia and severe acute respiratory syndrome(SARS)and Middle East respiratory syndrome(MERS),[6]this study primarily discusses clinical indications and provides details regarding the prevention of nosocomial infections during NPPV and HFNC treatment of COVID-19 pneumonia based on previous clinical data on the use of these two therapies for SARS and MERS and our experience with the treatment of COVID-19 pneumonia.展开更多
Due to improved soil deliverability and high reactivity,stabilized nanoparticles have been studied for nearly two decades for in situ remediation of soil and groundwater contaminated with organic pollutants.While larg...Due to improved soil deliverability and high reactivity,stabilized nanoparticles have been studied for nearly two decades for in situ remediation of soil and groundwater contaminated with organic pollutants.While large amounts of bench-and field-scale experimental data have demonstrated the potential of the innovative technology,extensive research results have also unveiled various merits and constraints associated different soil characteristics,types of nanoparticles and particle stabilization techniques.Overall,this work aims to critically overview the fundamental principles on particle stabilization,and the evolution and some recent developments of stabilized nanoparticles for degradation of organic contaminants in soil and groundwater.The specific objectives are to:1)overview fundamental mechanisms in nanoparticle stabilization;2)summarize key applications of stabilized nanoparticles for in situ remediation of soil and groundwater contaminated by legacy and emerging organic chemicals;3)update the latest knowledge on the transport and fate of stabilized nanoparticles;4)examine the merits and constraints of stabilized nanoparticles in environmental remediation applications;and 5)identify the knowledge gaps and furore research needs pertaining to stabilized nanoparticles for remediation of contaminated soil and groundwater.Per instructions of this invited special issue,this review is focused on contributions from our group(one of the pioneers in the subject field),which,however,is supplemented by important relevant works by others.The knowledge gained is expected to further advance the science and technology in the environmental applications of stabilized nanoparticles.展开更多
基金Project supported by the National Outstanding Youth Science Fund Project(Grant No.12125206)the Fund from the Basic Science Center for“Multiscale Problems in Nonlinear Mechanics”(Grant No.11988102)the General Project of the National Natural Science Foundation of China(Grant No.11972345)。
文摘Boson peak of glasses,a THz vibrational excess compared to Debye squared-frequency law,remains mysterious in condensed-matter physics and material science.It appears in many different kinds of glassy matters and is also argued to exist in damped crystals.A consensus is that boson peak originates from the coupling of the(quasi)-localized non-phonon modes and the plane-wave-like phonon modes,but the coupling behavior is still not fully understood.In this paper,by modulating the content of localized modes and the frequencies of phonon modes,the coupling is clearly reflected in the localization and anharmonicity of low-frequency vibrational modes.The coupling enhances with increasing cooling rate and sample size.For finite sample size,phonon modes do not fully intrude into the low frequency to form a dense spectrum and they are not sufficiently coupled to the localized modes,thus there is no Debye level and boson peak is ill-defined.This suggestion remains valid in the presence of thermal motions induced by temperature,even though the anharmonicity comes into play.Our results point to the coupling of quasi-localized and phonon modes and its relation to the boson peak.
基金Supported by The Key Research and Development Projects of Sichuan Science and Technology Department,No.2023YFS0285Natural Science Foundation Project of Sichuan Science and Technology Department,No.2023NSFSC0613.
文摘BACKGROUND Ulcerative colitis(UC)is an inflammatory condition with frequent relapse and recurrence.Evidence suggests the involvement of SLC6A14 in UC pathogenesis,but the central regulator remains unknown.AIM To explore the role of SLC6A14 in UC-associated pyroptosis.METHODS Quantitative real-time polymerase chain reaction(qRT-PCR),immunoblotting,and immunohistochemical were used to assess SLC6A14 in human UC tissues.Lipopolysaccharide(LPS)was used to induce inflammation in FHC and NCM460 cells and model enteritis,and SLC6A14 levels were assessed.Pyroptosis markers were quantified using enzyme-linked immunosorbent assay,Western blotting,and qRT-PCR,and EdU incubation,CCK-8 assays and flow cytometry were used to examine proliferation and apoptosis.Mouse models of UC were used for verification.RESULTS SLC6A14 was increased and correlated with NLRP3 in UC tissues.LPS-induced FHC and NCM460 cells showed increased SLC6A14 levels.Reducing SLC6A14 increased cell proliferation and suppressed apoptosis.Reducing SLC6A14 decreased pyroptosis-associated proteins(ASC,IL-1β,IL-18,NLRP3).NLRP3 overexpression counteracted the effects of sh-SLC6A14 on LPS-induced FHC and NCM460 cell pyroptosis.SLC6A14 improved the mucosa in mice with dextran sulfate sodium-induced colitis.CONCLUSION SLC6A14 promotes UC pyroptosis by regulating NLRP3,suggesting the therapeutic potential of modulating the SLC6A14/NLRP3 axis.
基金supported by the National Natural Science Foundation of China(Grant No.31871547)。
文摘Flavonoids are important bioactive components in Dendrobium officinale,a medicinal orchid.They are involved in many biological activities,including protecting plants against biotic and abiotic stresses.Research on the key genes related to flavonoid biosynthesis in D.officinale is limited.In this study,one of the key flavonoid biosynthesis genes,flavanone 3-hydroxylase(F3H),was characterized from D.officinale.The open reading frame of DoF3H was 1134 bp long and it encoded a 377-amino acid protein.The DoF3H protein showed considerably high homology with F3H proteins from other plant species and shared a common evolutionary ancestor with other F3Hs.DoF3H transcripts were detected in different organs of adult plants and mainly accumulated in flowers,followed by roots,stems and leaves,a pattern that was similar to the content of flavonoids.Recombinant DoF3H protein,which was localized in the cytosol,could convert naringenin to dihydrokaempferol.The mRNA levels of DoF3H were significantly induced by salt and cold stresses.Furthermore,the heterologous expression of DoF3H in Escherichia coli conferred it higher tolerance to salt and cold stresses.These results provide insight into the molecular function of DoF3H in the biosynthesis of flavonoids,and provide a new application for improvement of abiotic tolerance in D.officinale.
文摘目的讨论老年冠状动脉搭桥术后平均动脉压与急性肾损伤的关系。方法选择250例行体外循环下冠状动脉搭桥的老年患者,根据术后平均动脉压分为4组:66~70 mm Hg组、71~75 mm Hg组、76~80 mm Hg、≥81 mm Hg组,回顾性比较各组的术后6 h乳酸清除率、急性肾损伤发生率、住重症监护室(ICU)时间、30 d死亡率。结果 4组患者间术后急性肾损伤发生率及30 d死亡率比较,差异无统计学意义(P>0.05)。平均动脉压71~75 mm Hg组较其他3组患者的术后6 h乳酸清除率高、住ICU时间短,差异有统计学意义(P<0.05)。结论老年冠状动脉搭桥术后进一步提高高于65 mm Hg的平均动脉压并不能减少急性肾损伤的发生率。
基金funded by the National Natural Science Foundation of China(Grant No.51779021)Chongqing Natural Science Foundation(Grant No.cstc2019jcyj-msxm2176)Scientific and Technological Research Program of Chongqing Municipal Education Commission(Grant No.KJQN201800745).
文摘In deep underground engineering,understanding of time-related stress memory properties is critical to evaluate the in situ stress conditions of a rock mass.In this study,the time-sensitivity mechanism of the rock stress memory properties under tensile stress was investigated.It was found that the material property(Poisson’s ratio)and crack angle were the controlling factors of the Kaiser effect(KE)under tensile stress.In particular,the time-sensitivity of the stress memory properties was closely related to the crack growth path.When the failure of the rock specimen was dominated by tensile microcracks and the crack development direction was deflected by up to 30°in the successive loading process,the stress memory capacity was likely to be time-independent for a sandstone specimen.The distribution of the Felicity ratio in a Brazilian test was more discrete than that in a three-point bending test It also showed that the changes in the crack path,rather than the time interval between successive loading cycles,led to inaccuracy of the detected KE.This study provides insights into stress memory-related issues under uniaxial or more complex stress conditions and thus facilitates development of methods for testing in situ mechanical behaviors of rocks with acoustic emission(AE)technology.
基金Construction Project of TCM Academic Schools Inheritance Studio of State Administration of Traditional Chinese Medicine(No.LPGZS2012-14)Construction Project of National Famous Old TCM Experts Inheritance Studio of State Administration of Traditional Chinese Medicine.
文摘Objective:To observe the effects of resveratrol on myocardial cell injury and Mst1/Sirt3 signaling pathway mediated autophagy in type 2 diabetic mice. Methods:C57 BL/KSJ db/db mice were allocated to the normal control group,the model group,and the resveratrol group;C57 BL/KSJ db/m mice served as the melbine group,with 10 mice each. The resveratrol group and the melbine group were treated with resveratrol and metformin by gavage,respectively. The normal control group and the model group were treated with equal volume of normal saline by gavage,for 8 consecutive weeks. H & E staining,transmission electron microscopy and immunofluorescence were used to observe the pathological morphology,ultrastructure and apoptosis levels of myocardial tissues,respectively. RT-qPCR method was used to detect the expression levels of apoptosis genes Bax and Bcl-2 in myocardial tissues,and Western-blot method was used to detect the expression levels of autophagy proteins(LC3 and p62),Mst1 and Sirt3 proteins in myocardial tissue. Results:Compared with the model group,resveratrol can significantly reduce the body weight,blood glucose level and serum CK and LDH levels of db/db mice,and the differences were statistically significant(P<0.05;P<0.01). Meanwhile,after resveratrol treatment,myocardial inflammation score,apoptosis rate,Bax mRNA expression level and Bax/Bcl-2 ratio in myocardial tissue were significantly reduced,and Bcl-2 mRNA expression level was significantly increased,and the differences were statistically significant(P<0.01). In addition,compared with the model group,the expression level of p62 and p-Mst1 protein in the myocardial tissue of the resveratrol group was significantly reduced,and the expression level of Sirt3 protein and the ratio of LC3Ⅱ/LC3Ⅰ were significantly increased,and the differences were statistically significant(P<0.01). Conclusion:Resveratrol promotes the autophagy level of cardiomyocytes by activating the Mst1/Sirt3 signaling pathway and inhibits cardiomyocyte apoptosis to play a protective role in diabetic cardiomyopathy.
基金Clinical Medical Research Project of Wuhan Municipal Health and Family Planning Commission(No.WZ20Q12)Major project of the National Natural Science Foundation of China"Clinical Application Research on Different Functional States of Acupoints"(No.81590955)。
文摘Objective:To observe the clinical effect of electroacupuncture"Tongmin point"combined with heat-sensitive moxibustion on knee osteoarthritis and its effect on blood lipid level,polyprotein polysaccharide enzyme-4(a disintegrin and metalloprotease with thrombospondin motifs,ADAMTS-4,matrix metalloproteinase-3(matrix metalloproteinase-3,);and MMPs-3)Impact.Methods:80 patients were randomly divided into two groups,40 cases per group,Treatment and control groups,The treatment group was given electroacupuncture combined with heat-sensitive moxibustion,Six times a week,Continuous treatment for 4 weeks;The control group was given intraarticular sodium hyaluronate,Once a week,continuous treatment for 4 weeks.Results:During the treatment period,Visual analogue scale visual analogue scale,VAS)show a downward trend,Intra-group comparisons,Differences were statistically significant(P<0.05);After 2 weeks of treatment,4 weeks of treatment and 2 weeks of follow-up,All the scores in the treatment group were lower than those in the control group(P<0.05).After treatment in two groups(The Western Ontario and Mc Master Universities Osteoarthritis Index,)of osteoarthritis index,University of Western Ontario WOMAC)The scores of each item decreased significantly,treatment group was better than the control group(P<0.05).After four weeks of treatment,(Total cholesterol,)Total cholesterol TC,triglycerides(Triglyceride,);and TG,LDL(Low density lipoprotein,);and LDL-C)A decrease in content,High density lipoprotein High density lipoprotein,HDL-C)Increased content,and the improvement was better than that of the control group(P<0.05).After treatment,the ADAMTS-4,MMPs-3 content decreased,Intergroup comparisons,Differences were statistically significant(P<0.05);The effective rate in the treatment group was 87.5%,The control rate was 60%,treatment group was more effective(P<0.05).Conclusions:Electroacupuncture"Tongmin point"combined with heat-sensitive moxibustion can obviously improve the symptoms of knee osteoarthritis patients,Regulate blood lipids,High security,It is worth popularizing in clinic.
基金Research Project Funding of Health and Family Planning Commission of Wuhan(No.WZ20Q12)Key Program of the National Natural Science Fund of China(No.81590955)。
文摘Objective:To observe the expression of CTX-I(Ⅰcollagen C-terminal foreign body peptide)and TRACP(tartrate-resistant acid phosphatase)in different syndromes of knee osteoarthritis and their correlation with ADAMTS-4(polyproteoglycan enzyme-4)and MMPS-3(matrix metalloproteinase-3).Methods:A total of 98 patients diagnosed with knee osteoarthritis were enrolled from the Rehabilitation Pain Department and Rheumatology Department of Wuhan Caidian District People's Hospital.According to their syndrome types,they were divided into 40 cases of Yang deficiency and cold constipation type,28 cases of qi stagnation and blood stasis type,and 30 cases of kidney jing deficiency type.The contents of bone metabolism indexes,ADAMTS-4 and MMPS-3 in different syndromes of the three groups were compared.Correlation of bone metabolism indexes with ADAMTS-4 and MMPS-3.Results:There were statistically significant differences in the contents of CTX-I,TRACP,ADAMTS-4 and MMPS-3 among three groups with different syndromes(P<0.05).There was a positive correlation between CTX-I,TRACP,ADAMTS-4 and MMPS-3(P<0.05).The syndrome of qi stagnation and blood stasis was positively correlated with TRACP and ADAMTS-4,and negatively correlated with MMPS-3(P<0.05).The renal essence deficiency syndrome was positively correlated with CTX-I,ADAMTS-4 and MMPS-3(P<0.05).Bone metabolic indexes(CTX-I,TRACP)were positively correlated with ADAMTS-4 and MMPS-3(P<0.05).Conclusion:Different syndromes of knee osteoarthritis are correlated with bone metabolism indexes,ADAMTS-4 and MMPS-3,which can provide a certain objective basis for clinical TCM syndrome differentiation and classification。
基金supported by the National Outstanding Youth Science Fund Project (Grant No. 12125206)Basic Science Center for “Multiscale Problems in Nonlinear Mechanics”(Grant No. 11988102)+1 种基金General Project of National Natural Science Foundation of China (Grant No. 11972345)CAS Project for Young Scientists in Basic Research (Grant No. YSBR-096)。
文摘Physical aging is an inherent property of glassy matter, but understanding its microscopic mechanism remains a challenge particularly at the particle level. In this work, we use a confocal microscope to in-situ trace the particle trajectories in a 3D colloidal glass for 73000 s, aiming at resolving the aging dynamics. By calculating the mean square displacement of particle motions, we find that the glass aging with time can be divided into three stages: β relaxation, α relaxation and free diffusion. The system's mean square displacement at each aging state is quantitatively resolved into three contributions of particle dynamics modes: vibration within the nearest-neighbor cages, hopping between cages and cooperative rearrangement. We further calculate the particle's free volume and find that the β-to-α transition is accompanied by the temporary increase of the system-averaged free volume due to pronounced hops of particles. Nevertheless, the temporal autocorrelation of the free volume spatial distribution still obeys a monotonically stretched exponential decay with an exponent of 0.76, which is related to the sub-diffusion dynamics of cooperative rearrangements and hops mixed in α relaxation. According to the resolved vibrational displacements,we calculate the vibrational density of states of this 3D glass, and the characteristic boson peak is reproduced at low frequencies.Our findings shed insight into the particle-level aging dynamics of a real glass under purely thermal activation.
文摘Recently,there has been growing interest in knowing the best hygrometry level during high-flow nasal oxygen and non-invasive ventilation(NIV)and its potential influence on the outcome.Various studies have shown that breathing cold and dry air results in excessive water loss by nasal mucosa,reduced mucociliary clearance,in-creased airway resistance,reduced epithelial cell function,increased inflammation,sloughing of tracheal epithe-lium,and submucosal inflammation.With the Coronavirus Disease 2019 pandemic,using high-flow nasal oxygen with a heated humidifier has become an emerging form of non-invasive support among clinicians.However,we cannot always assume stable humidification.Similarly,there are no clear guidelines for using humidification dur-ing NIV,although humidification of inspired gas during invasive ventilation is an accepted standard of care.NIV disturbs the normal physiological system that warms and humidifies inspired gases.If NIV is supplied through an intensive care unit ventilator that utilizes anhydrous gases from compressed wall air and oxygen,the risk of dry-ness increases.In addition,patients with acute respiratory failure tend to breathe through the mouth during NIV,which is a less efficient route than nasal breathing for adding heat and moisture to the inspired gas.Obstructive sleep apnea syndrome is one of the most important indications for chronic use of NIV at home.Available data suggest that up to 60%of patients with obstructive sleep apnea syndrome who use continuous positive airway pressure therapy experience nasal congestion and dryness of the mouth and nose.Therefore,humidifying the inspired gas in NIV may be essential for patient comfort and compliance with treatment.We aimed to review the available bench and clinical studies that addressed the utility of hygrometry in NIV and nasal high-flow oxygen and discuss the technical limitations of different humidification systems for both systems.
基金Financial support from the Fundamental Research Funds for the Central Universities(No.2019MS041)Postdoctoral Science Foundation of China(No.2021M690208)。
文摘Water pollution has become a serious problem owing to the development of society.Photocatalysis is a promising approach to remove various pollutants in water,such as organic pollutants and antibiotic resistance bacteria.Meanwhile,the design of heterojunction between two semiconductors is an effective path to improve photocatalytic properties due to its potential in improving separation and transfer of photoinduced carriers.In this study,Nb_(2)O_(5)/g-C_(3)N_(4)(NO/CN)composite materials were prepared through a one-step heating method.Characterizations confirmed successful preparation of NO/CN heterojunction structure and better optical properties than pure g-C_(3)N_(4) and Nb_(2)O_(5).NO/CN composite materials showed excellent photocatalytic efficiency for Escherichia coli(E.coli)inactivation(95%)compared with the pure Nb_(2)O_(5)(10%) and g-C_(3)N_(4)(77%).Meanwhile,NO/CN exhibited better organic pollutants removal(Rh B for94%,methyl orange(MO)for 15%and methylene blue(MB)for 87%)under visible light,which is likely owing to the heterojunction structure between g-C_(3)N_(4) and Nb_(2)O_(5) that leads to the good separation of photogenerated electron-hole pair.Free radical scavenging and electron spin resonance(ESR)experiments demonstrated that superoxide radicals(·O_(2)^(-)) and holes(h^(+)) were the dominant radicals.Therefore,the NO/CN was proposed to be a promising material for effective disinfection and removal of organic contaminants in water treatment.
基金supported by the National Key Research and Development Program of China(No.2019YFC0214802)the Youth Innovation Promotion Association,CAS(No.2019434)the Sino-German Mobility programme(No.M-0036)。
文摘Accurate monitoring of the atmospheric environment and its evolution are important for understanding the sources,chemical mechanisms,and transport processes of air pollution and carbon emissions in China,and for regulatory and control purposes.This study gives an overview of atmospheric environment monitoring technology and equipment in China and summarizes the major achievements obtained in recent years.China has made great progress in the development of atmospheric environment monitoring technology and equipment with decades of effort.The manufacturing level of atmospheric environment monitoring equipment and the quality of products have steadily improved,and a technical&production system that can meet the requirements of routine monitoring activities has been initiated.It is expected that domestic atmospheric environment monitoring technology and equipment will be able to meet future demands for routine monitoring activities in China and provide scientific assistance for addressing air pollution problems.
基金supported by the National Key Research and Development Program of China(No.2017YFC0209900)Beijing Nova Program from Beijing Municipal Science&Technology Commission(No.Z201100006820098)the Youth Science and Technology Talents Support Program(2020)by Anhui Association for Science and Technology(No.RCTJ202002)。
文摘Abrupt air pollution accidents can endanger people’s health and destroy the local ecological environment.The appropriate emergency response can minimize the harmful effects of accidents and protect people’s lives and property.This paper provides an overview of the key emergency response technologies for abrupt air pollution accidents around the globe with emphasis on the major achievements that China has obtained in recent years.With decades of effort,China has made significant progress in emergency monitoring technologies and equipment,source estimation technologies,pollutant dispersion simulation technologies and others.Many effective domestic emergency monitoring instruments(e.g.,portable DOAS/FT-IR systems,portable FID/PID systems,portable GC-MS systems,scanning imaging remote sensing systems,and emergency monitoring vehicles)had been developed which can meet the demands for routine emergency response activities.A monitoring layout technique combining air dispersion simulation,fuzzy comprehensive evaluation,and a post-optimality analysis was proposed to identify the optimal monitoring layout scheme under the constraints of limited monitoring resources.Multiple source estimation technologies,including the forward method and the inversion method,have been established and evaluated under various scenarios.Multi-scale dynamic pollution dispersion simulation systems with high temporal and spatial resolution were further developed.A comprehensive emergency response platform integrating database support,source estimation,monitoring schemes,fast monitoring of pollutants,pollution predictions and risk assessment was developed based on the technical idea of"source identification-model simulation-environmental monitoring"dynamic interactive feedback.It is expected that the emergency response capability for abrupt air pollution accidents will gradually improve in China.
基金supported by grants from the National Natural Science Foundation of China(Grant No.32071819)Natural Science Foundation of Guangdong Province(Grant No.2021A1515012170)the Key-Area Research and Development Program of Guangdong Province(Grant No.2022B0202080002)。
文摘Orchid plants develop protocorms upon germination and produce protocorm-like structures called protocorm-like bodies(PLBs)from protocorms and somatic cells via tissue culture.Protocorm-like bodies have broad technical application potential in the orchid industry and their regeneration is a distinct developmental process in the plant kingdom.However,little is known about this unparalleled developmental program.In this study,we identified a PLB-abundant gene,ethylene response factor(ERF),and a transcription factor named Do ERF5,and determined its important role in PLB regeneration in Dendrobium orchid.Overexpression of Do ERF5 in Dendrobium greatly enhanced the PLB regeneration from PLB and stem explants,and upregulated the expression of WOUND-INDUCED DEDIFFERENTIATION(Do WIND)homologs and SHOOT MERISTEMLESS(Do STM),as well as the genes involved in cytokinin biosynthesis(Do IPT)and the cytokinin response factors(Do ARRs).However,silencing Do ERF5 reduced the regeneration rate of PLBs,and downregulated the expression of Do WIND homologs,Do STM and Do ARRs.We demonstrated that Do ERF5 is directly bound to the Do STM promoter and regulates its expression.In addition,overexpression of Do STM in Dendrobium orchid resulted in favorable regeneration of PLBs.Our results clarify that Do ERF5 regulates the regeneration of PLB by enhancing Do STM expression.Our findings provide new insights into how Do ERF5 mediates PLB regeneration and offers technical potential in improving clonal propagation,preservation,and the bioengineering of orchids.
文摘Gene expression quantification at mRNA level is very important for postgenomic studies, as gene expression level is the reflection of the special biological function of the target gene. Methods used for gene expression quantification, such as microarray or quantitative real-time polymerase chain reaction （qRT-PCR）, require stable expressed reference genes. Thus, finding suitable control genes is essential for gene quantification. In this study, a genome-wide survey of reference genes during metamorphism was performed on silkworm Bombyx mori. Twelve genes were chosen as putative reference genes based on a whole genome oligonucleotide microarray normalized by external controls. Then, qRT- PCR was employed for further validation and selection of potential reference gene candidates. The results were analyzed, and stable genes were selected using geNorm 3.4 and NormFinder software. Finally, considering factors from every aspect, translation initiation factor 4A, translation initiation factor 3 subunit 4, and translation initiation factor 3 subunit 5 （represented by sw22934, sw14876, and sw13956） were selected as reliable internal controls across the examined developmental stages, while cytoplasmic actin （sw22671）, the commonly used reference gene in a previous study was shown to vary drastically throughout the examined developmental stages. For future research, we recommend the use of the geometric mean of those three stable reference genes as an accurate normalization factor for data normalization of different developmental stages during metamorphism.
基金partially supported by the National Natural Science Foundation of China(No.41230638)a grant from the USDA AAES 2015 Hatch and Multistate funding program
文摘Reductive immobilization of radioactive pertechnetate(99TcO4^-) in simulated groundwater was studied by prepared carboxymethyl cellulose(CMC) and starch stabilized zero valent iron nanoparticles(nZVI),and long-term remobilization of reduced Tc was also evaluated under anoxic and oxic conditions.The stabilized nZVI can effectively reduce soluble 99Tc(Ⅶ) to insoluble 99 Tc(Ⅳ),and they can be easily delivered into a contaminated groundwater zone and facilitate in situ remediation.In this study,CMCstabilized nZVI showed higher reactivity than that using starch as the stabilizer.Batch experiments indicated that more than 99% of 99 Tc(Ⅶ)(CO=12 mg/mL) was reduced and removed from groundwater by CMC-stabilized nZVI with a CMC content of 0.2%(w/w) at a broad pH of 5-8.X-ray diffraction(XRD)and X-ray photoelectron spectroscopy(XPS) analyses further confirmed that 99Tc(Ⅶ)O4^-transformed into 99Tc(Ⅳ)O2(s).The presence of bicarbonate exhibited insignificant effect on Tc immobilization,while humic acid(HA) inhibited reaction mainly due to retardation on electron transfer and formation of Tc(IV)-HA complexes.More interesting,the immobilized Tc(Ⅳ) remained insoluble even after 120 d under anoxic condition,while only^21 % was remobilized when exposed to air.Therefore,biomacromolecules stabilized nZVI nanoparticles could be a viable alternative for in situ remediation of radioactive contamination in groundwater.
基金the National Natural Science Foundation of China(Nos.21906001 and 52100069)the National Key Research and Development Program of China(No.2021YFA1202500)+2 种基金Beijing Nova Program(No.Z191100001119054)the Fundamental Research Funds for the Central Universities(No.BFUKF202118)China Postdoctoral Science Foundation(No.2021M690208)。
文摘Peracetic acid(PAA)-based system is becoming an emerging advanced oxidation process(AOP)for effective removal of organic contaminants from water.Various approaches have been tested to activate PAA,while no previous researches reported the application of metal-organic frameworks(MOFs)materials for PAA activation.In this study,zeolitic imidazole framework(ZIF)-67,a representative MOFs,was facile synthesized via direct-mixing method at room temperature,and tested for PAA activation and sulfachloropyridazine(SCP)degradation.The as-synthesized ZIF-67 exhibited excellent performance for PAA activation and SCP degradation with 100%of SCP degraded within 3 min,owing to the specific MOFs structure and abundant Co^(2+) sites.The pseudo-first-order kinetic model was applied to fit the kinetic data,with rate constant k_(1) of ZIF-67 activated PAA system 34.2 and 156.5 times higher than those of conventional Co_(3)O_(4)activated PAA and direct oxidation by PAA.Radical quenching experiments and electron paramagnetic resonance(EPR)analysis indicated that CH_(3)C(O)OO^(·)played a major role in this PAA activation system.Then,the Fukui index based on density functional theory(DFT)calculation was used to predict the possible reaction sites of SCP for electrophilic attack by CH_(3)C(O)OO^(·).In addition,the degradation pathway of SCP was proposed based on Fukui index values and intermediates detection,which mainly included the S-N bond cleavage and SO_(2)extrusion and followed by further oxidation,dechlorination,and hydroxylation.Therefore,ZIF-67 activated PAA is a novel strategy and holds strong potential for the removal of emerging organic contaminants(EOCs)from water.
基金This study was supported by grants from the National Key Research and Development Program of China(No.2016YFC1304300)Chinese Academy of Medical Sciences(CAMS)Innovation Fund for Medical Sciences(No.2018-I2M-1-003)+1 种基金Non-profit Central Research Institute Fund of CAMS(No.2019TX320006)the National Natural Science Foundation of China(No.81870072)。
文摘Introduction Pneumonia caused by a novel coronavirus known as 2019 novel coronavirus disease(COVID-19)[1]appeared in Wuhan,China in December 2019,and approximately 15%to 30%of patients developed acute respiratory distress syndrome within a short period of time.[2,3]To reduce respiratory symptoms and improve prognosis,respiratory support is the most important means of life support,[1]and non-invasive respiratory support systems,[2]including various conventional oxygen therapies,non-invasive positive pressure ventilation(NPPV),and high-flow nasal cannula(HFNC),are most commonly used.However,their efficacy and safety remain unclear,and whether they increase the risk of aerosol dispersion and disease transmission is particularly controversial.[4,5]Given that there are many similarities between COVID-19 pneumonia and severe acute respiratory syndrome(SARS)and Middle East respiratory syndrome(MERS),[6]this study primarily discusses clinical indications and provides details regarding the prevention of nosocomial infections during NPPV and HFNC treatment of COVID-19 pneumonia based on previous clinical data on the use of these two therapies for SARS and MERS and our experience with the treatment of COVID-19 pneumonia.
基金supported by the Auburn University IGP Program,the National Natural Science Foundation of China(No.41807340)the Guangdong Innovative and Entrepreneurial Research Team Program(No.2016ZT06N569).
文摘Due to improved soil deliverability and high reactivity,stabilized nanoparticles have been studied for nearly two decades for in situ remediation of soil and groundwater contaminated with organic pollutants.While large amounts of bench-and field-scale experimental data have demonstrated the potential of the innovative technology,extensive research results have also unveiled various merits and constraints associated different soil characteristics,types of nanoparticles and particle stabilization techniques.Overall,this work aims to critically overview the fundamental principles on particle stabilization,and the evolution and some recent developments of stabilized nanoparticles for degradation of organic contaminants in soil and groundwater.The specific objectives are to:1)overview fundamental mechanisms in nanoparticle stabilization;2)summarize key applications of stabilized nanoparticles for in situ remediation of soil and groundwater contaminated by legacy and emerging organic chemicals;3)update the latest knowledge on the transport and fate of stabilized nanoparticles;4)examine the merits and constraints of stabilized nanoparticles in environmental remediation applications;and 5)identify the knowledge gaps and furore research needs pertaining to stabilized nanoparticles for remediation of contaminated soil and groundwater.Per instructions of this invited special issue,this review is focused on contributions from our group(one of the pioneers in the subject field),which,however,is supplemented by important relevant works by others.The knowledge gained is expected to further advance the science and technology in the environmental applications of stabilized nanoparticles.
