Temporomandibular joint(TMJ)disc displacement is one of the most significant subtypes of temporomandibular joint disorders,but its etiology and mechanism are poorly understood.In this study,we elucidated the mechanism...Temporomandibular joint(TMJ)disc displacement is one of the most significant subtypes of temporomandibular joint disorders,but its etiology and mechanism are poorly understood.In this study,we elucidated the mechanisms by which destruction of inflamed collagen fibrils induces alterations in the mechanical properties and positioning of the TMJ disc.By constructing a rat model of TMJ arthritis,we observed anteriorly dislocated TMJ discs with aggravated deformity in vivo from five weeks to six months after a local injection of Freund’s complete adjuvant.By mimicking inflammatory conditions with interleukin-1 beta in vitro,we observed enhanced expression of collagen-synthesis markers in primary TMJ disc cells cultured in a conventional two-dimensional environment.In contrast,three-dimensional(3D)-cultivated disc cell sheets demonstrated the disordered assembly of inflamed collagen fibrils,inappropriate arrangement,and decreased Young’s modulus.Mechanistically,inflammation-related activation of the nuclear factor kappa-B(NF-κB)pathway occurs during the progression of TMJ arthritis.NF-κB inhibition reduced the collagen fibril destruction in the inflamed disc cell sheets in vitro,and early NF-κB blockade alleviated collagen degeneration and dislocation of the TMJ discs in vivo.Therefore,the NF-κB pathway participates in the collagen remodeling in inflamed TMJ discs,offering a potential therapeutic target for disc displacement.展开更多
Catalytic destruction is an ascendant technology for the abatement of volatile organic compounds(VOCs)originating fromsolvent-based industrial processes.The varied composition tends to influence each VOC’s catalytic ...Catalytic destruction is an ascendant technology for the abatement of volatile organic compounds(VOCs)originating fromsolvent-based industrial processes.The varied composition tends to influence each VOC’s catalytic behavior in the reaction mixture.We investigated the catalytic destruction of multi-component VOCs including dichloromethane(DCM)and ethyl acetate(EA),as representatives from pharmaceutical waste gases,over co-supported HxPO_(4)-RuOx/CeO_(2) catalyst.A mutual inhibitory effect relating to concentrations because of competitive adsorption was verified in the binary VOCs oxidation and EA posed a more negative effect on DCM oxidation owing to EA’s superior adsorption capacity.Preferential adsorption of EA on acidic sites(HxPO_(4)/CeO_(2))promoted DCM activation on basic sites(O^(2−))and the dominating EA oxidation blocked DCM’s access to oxidation centers(RuOx/CeO_(2)),resulting in boosted monochloromethane yield and increased chlorine deposition for DCM oxidation.The impaired redox ability of Ru species owing to chlorine deposition in turn jeopardized deep oxidation of EA and its by-products,leading to increased gaseous by-products such as acetic acid originating fromEA pyrolysis.Notably,DCM at low concentration slightly promoted EA conversion at low temperatures with or without water,consistent with the enhanced EA adsorption in co-adsorption analyses.This was mainly due to that DCM impeded the shielding effect of hydrolysate deposition from rapid EA hydrolysis depending on the decreased acidity.Moreover,water benefited EA hydrolysis but decreased CO_(2) selectivity while the generated water derived from EA was likely to affect DCM transformation.This work may provide theoretical guidance for the promotion of applied catalysts toward industrial applications.展开更多
Photocatalytic disinfection is an eco-friendly strategy for countering bacterial pollution in aquatic environments.Numerous strategies have been devised to facilitate the generation of reactive oxygen species(ROS)with...Photocatalytic disinfection is an eco-friendly strategy for countering bacterial pollution in aquatic environments.Numerous strategies have been devised to facilitate the generation of reactive oxygen species(ROS)within photocatalysts,ultimately leading to the eradication of bacteria.However,the significance of the physical morphology of photocatalysts in the context of sterilization is frequently obscured,and the progress in the development of physical-chemical synergistic sterilization photocatalysts has been relatively limited.Herein,graphitic carbon nitride(g-C_(3)N_(4))is chemically protonated to expose more sharp edges.PL fluorescence and EIS results indicate that the protonation can accelerate photogenerated carrier separation and enhance ROS production.Meanwhile,the sharp edges on the protonated g-C_(3)N_(4)facilitate the physical disruption of cell walls for further promoting oxidative damage.Protonated C_(3)N_(4)demonstrated superior bactericidal performance than that of pristine g-C_(3)N_(4),effectively eliminating Escherichia coli within 40 minutes under irradiation.This work highlights the significance of incorporating physical and chemical synergies in photocatalyst design to enhance the disinfection efficiency of photocatalysis.展开更多
Dear Editor,I am Yuki Tanaka from Hakodate Central General Hospital,Japan.Mikulicz’s disease is characterized by symmetrical swelling of lacrimal and salivary glands.In 2012,a Japanese study group proposed comprehens...Dear Editor,I am Yuki Tanaka from Hakodate Central General Hospital,Japan.Mikulicz’s disease is characterized by symmetrical swelling of lacrimal and salivary glands.In 2012,a Japanese study group proposed comprehensive diagnostic criteria for immunoglobulin G4-related disease(IgG4-RD)^([1]).They have revealed that Mikulicz’s disease is a systemic IgG4-RD and attracted attentions of ophthalmologists.In 2014,the criteria for IgG4-related ophthalmic disease(IgG4-ROD)were established.展开更多
BACKGROUND Although laparoscopic gastrolithotomy had been widely used in clinical practice,uncommon postoperative complications still require vigilance by medical staff.CASE SUMMARY Here we report a 67-year-old man wh...BACKGROUND Although laparoscopic gastrolithotomy had been widely used in clinical practice,uncommon postoperative complications still require vigilance by medical staff.CASE SUMMARY Here we report a 67-year-old man who suffered for 18 months and underwent surgery several times due to a rare and undetected complication of laparoscopic gastricolithotomy.He presented to multiple hospitals because of sustained left upper quadrant abdominal pain one month after laparoscopic gastricolithotomy due to a large gastric bezoar caused by unrestrained eating of black dates and was diagnosed with possible intercostal neuritis.Many painkillers were used to relieve his symptoms but the condition progressed.Seven months after surgery,he was hospitalized as skin ulceration occurred in the left upper abdominal wall and was subsequently diagnosed with a massive thoracoabdominal wall abscess.One year after surgery,irreversible costal destruction was demonstrated.Both lesions were finally proved to be secondary damage due to a rare chronic gastro-abdominal wall fistula related to laparoscopic gastricolithotomy and the diameter of the gastric fistula reached 2 centimeters(cm).The patient was ultimately cured but underwent multi-regional incisions and drainage of the abscess,drainage of the gastric fistula,partial gastrectomy and removal of damaged ribs,and was followed-up for more than 4 years without recurrence.It is well-known that gastric fistula usually has an acute onset and occurs early after surgery,while chronic gastro-abdominal wall fistula especially with secondary massive thoracoabdominal wall abscess and costal destruction has rarely been reported.CONCLUSION This may be the first reported case of a chronic thoracoabdominal abscess and costal destruction caused by an undetected chronic gastro-abdominal wall fistula.We believe that this is a novel type of gastric fistula and the diagnosis and treatment were challenging.展开更多
With the continuous advancement of communication and unmanned aerial vehicle(UAV)technologies,the collaborative operations of diverse platforms,including UAVs and ground vehicles,have been significantly promoted.Howev...With the continuous advancement of communication and unmanned aerial vehicle(UAV)technologies,the collaborative operations of diverse platforms,including UAVs and ground vehicles,have been significantly promoted.However,battlefield uncertainties,such as equipment failures and enemy attacks,can impact these collaborative operations'stability and communication efficiency.To this end,we design a highly destruction-resistant air-ground cooperative resilient networking platform that aims to enhance the robustness of network communications by integrating ground vehicle information for UAV network deployment.It then incorporates the concept of virtual guiding force,enabling the UAV swarm to adaptively configure its network layout based on ground vehicle information,thereby improving network destruction resistance.Simulation results demonstrate that the UAV swarm involved in the proposed platform exhibits balanced flight energy consumption and excellent performance in network destruction resistance.展开更多
In order to improve the destruction efficiency of dioxins and also for developing new dioxin control technology, the destruction mechanisms of 2,3,7,8-tetrachlorodihenzo-p-dioxin （2,3,7,8-TCDD） by O3 and NO3, were i...In order to improve the destruction efficiency of dioxins and also for developing new dioxin control technology, the destruction mechanisms of 2,3,7,8-tetrachlorodihenzo-p-dioxin （2,3,7,8-TCDD） by O3 and NO3, were investigated employing quantum chemical calculations. For involved reactions, the microcosmic reaction processes were analyzed and depicted in detail based on geometry optimizations made by the B3LYP/6-31G（d） method. At the same time, the reaction activation energies were also calculated at the MP2/6- 311G（d,p）//B3LYP/6-31G（d） level. Configuration analysis indicated that 2,3,7,8-TCDD could be destroyed by 03 and NO3 in two different ways. The destruction of 2,3,7,8-TCDD by 03 proceeded via the addition of 03 and the cleavage of C=C while the destruction of 2,3,7,8-TCDD by NO3 proceeded via the substitution of chlorine by NO3. Calculated results show that, the activation energy of the destruction reaction of 2,3,7,8-TCDD by NO3 （267.48 kJ/mol） is much larger than that of the destruction reaction of 2,3,7,8-TCDD by O3 （51.20 kJ/mol）. This indicated that the destruction of 2,3,7,8-TCDD by 03 is much more efficient than that of 2,3,7,8-TCDD by NO3. The reason why the activation energy for the destruction reaction of 2,3,7,8-TCDD by NO3 is so large, is also discussed.展开更多
We aimed to investigate the synergistic effects of ultrasonic waves and repeated freeze-thaw cycles on cel-wal destruction of Auricularia auric-ula mycelia, and determine the best combination of conditions for cel-wal...We aimed to investigate the synergistic effects of ultrasonic waves and repeated freeze-thaw cycles on cel-wal destruction of Auricularia auric-ula mycelia, and determine the best combination of conditions for cel-wal destruc-tion of Auricularia auricula mycelia. [Method] The effects of destruction time, added water, destruction times, freeze time and number of freeze-thaw cycles during ultra-sonic treatment on polysaccharide yield were investigated by single-factor test in our research. The optimum conditions for cel-wal destruction of Auricularia auricula mycelia by the synergistic effect of ultrasonic waves and repeated freeze-thaw cycles were ascertained by orthogonal test. [Result] The results of single test indicated the best combination of conditions was as fol ows： freeze time, 30 min; destruction time, 20 min; added water, 15 times; destruction times, 2 times; number of freeze-thaw cycles, 3 cycles. The results of orthogonal test indicated the influencing factors ranked as destruction time 〉 destruction times 〉 freeze time. The best combination of conditions was as fol ows： freeze time, 30 min; destruction time, 25 min; destruc-tion times, 2 times. Under above conditions, the polysaccharide yield reached 57.76 mg/g. [Conclusion] This research would provide a basis and reference for practical production.展开更多
The North China Craton(NCC)is the best example of an Archean craton that has lost its stability in the Late Mesozoic.Although the cratonic destruction is generally considered to have occurred in the Eastern Block and ...The North China Craton(NCC)is the best example of an Archean craton that has lost its stability in the Late Mesozoic.Although the cratonic destruction is generally considered to have occurred in the Eastern Block and reached a peak in the Early Cretaceous,the exact areal extent of cratonic destruction is debated,especially the southern and northern margin of the NCC.Here we report geochronology,geochemical and Hf isotopic data of the Late Mesozoic granitoids from Lushi polymetal mineralization area(LPMA)in the southern margin of NCC.These results provide new insights into the destruction in the southern margin of the NCC during the Late Mesozoic.Zircon U-Pb dating indicates that eight granitoids intruded in the Late Jurassic to Early Cretaceous(136.8–154.1 Ma),respectively.Geochemical signatures define these granitoids being A-type or I-type granite that formed in an extension setting.In addition,Hf isotopic compositions of zircons from these granitoids vary in a relatively large range,withεHf(t)values and TDM2 ages ranginge from-26.1 to+15.2 and 215 to 2849 Ma,respectively.The parental magmas were likely derived from diverse sources,including materials of the partial melting of ancient lower crust and mantle-derived mafic magmas in various proportions.Combining with previous studies on the contemporaneous magma-tectonic activities in circum of NCC,we suggest that the rim of NCC was already unstabilized from the Late Jurassic in the LPMA.The subduction of the Paleo-Pacific Plate was the main trigger to the destruction of the southern margin of NCC,which was responsible for the lithospheric extension and thinning,extensive magmatism and mineralization.展开更多
[Objective]To investigate the inhibitory effect ofhonokiol on Candida albicans in vitro.[Methods]The minimum inhibitory concentration(MIC)and minimum fungicidal concentration(MFC)of magnolol for C.albicans were determ...[Objective]To investigate the inhibitory effect ofhonokiol on Candida albicans in vitro.[Methods]The minimum inhibitory concentration(MIC)and minimum fungicidal concentration(MFC)of magnolol for C.albicans were determined by microdilution method.Transmission electron microscopy was used to examine the effect of different concentrations of honokiol on the ultrastructure of C.albicans.Apoptosis of C.albicans caused by honokiol was analyzed by Annexin V-FITC/propidium iodide(PI)double staining and the accumulation of reactive oxygen species(ROS)in C.albicans cells was determined by DCFH-DA staining.The effects of honokiol on mitochondrial membrane potential and cell membrane permeability of C.albicans were analyzed by JC-1 staining and PI staining respectively.[Results]Honokiol had strong inhibitory effect on C.albicans,with MIC90 of 16μg/mL and MFC of 32μg/mL.Honokiol affected cell wall,cell membrane,and cytoplasm of C.albicans,induced both apoptosis and necrosis in C.albicans,probably through ROS production and disruption of mitochondrial function.It also changed the permeability of cell membrane,leaded to the cell wall damage and the binding of ergosterol.[Conclusion]Inhibition of C.albicans by honikiol involves multiple mechanisms including ROS production accompanied by a series of cellular damages.Honikiol appears to be a potential antifungal drug candidate.展开更多
A series of zeolites,including USY zeolites without sodium,Na-USY at different Na contents,La-USY with different rare earth（RE） contents and La-Na-USY with RE and Na were prepared by an ion exchange method.They were...A series of zeolites,including USY zeolites without sodium,Na-USY at different Na contents,La-USY with different rare earth（RE） contents and La-Na-USY with RE and Na were prepared by an ion exchange method.They were investigated to understand the activation barriers for the destruction of Y zeolite structure under hydrothermal treatment and the effect of V using the solid-state kinetic model.The results showed that the pathways for Y zeolite destruction were dealumination,desiliconization and the disappearance of La-O bonds.Zeolites were destroyed by steam through acid hydrolysis,which was accelerated by V.In addition,Na and V exerted a synergistic effect on the framework destruction,and the formation of NaOH was the rate-determining step.The presence of RE elements decreased hydrolysis and stabilized the structure of the zeolites.The interaction between V and RE destroyed zeolite structure by eliminating the stabilizing La-O[RE-OH-RE]^（5＋）bridges in the sodalite cages.展开更多
AIM： To detect the therapeutic effects of chemical destruction of celiac ganglion in patients with pancreatic carcinoma with intractable pain. METHODS： Ninety-seven cases with advanced pancreatic carcinoma received ...AIM： To detect the therapeutic effects of chemical destruction of celiac ganglion in patients with pancreatic carcinoma with intractable pain. METHODS： Ninety-seven cases with advanced pancreatic carcinoma received chemical destruction of celiac ganglion-5 mL pure alcohol injection around celiac artery under ultrasonic guidance. The changes of visual analogue scale （VAS）, serum substance P （Sub P）, β-endopeptide （β-EP） and T-lymphocyte subtypes level were compared between pre- and post-therapy. RESULTS： Successful rate of puncture was 98.7%, with one failure. No serious complications such as traumatic pancreatitis, pancreatic fistula, abdominal cavity hemorrhage or peritoneal infection occurred. VAS, serum Sub P and β-EP level significantly changed after treatment （8.0 ± 2.3 vs 4.6 ± 2.1, 254.1 ± 96.7 vs 182.4 ± 77.6, 3.2 ± 0.8 vs 8.8 ± 2.1, P 〈 0.01, P 〈 0.05, P 〈 0.01） with complete relief rate 54.2%, partial relief rate 21.9%, ineffective rate 12.5% and recurrent rate 10.7%. The T-lymphocyte subtypes level remarkably increased when compared with that of pre-therapy （46.7 ± 3.7 vs 62.5 ± 5.5, P 〈 0.01）. CONCLUSION： Our study suggests that chemical destruction of celiac ganglion under ultrasonic guidance is highly safe, and can evidently relieve cancer pain and improve the cellular immunity in patients with advanced pancreatic carcinoma.展开更多
Background:Ultrasound-triggered microbubble destruction(UTMD) is a widely used noninvasive technology in both military and civilian medicine,which could enhance radiosensitivity of various tumors.However,little inform...Background:Ultrasound-triggered microbubble destruction(UTMD) is a widely used noninvasive technology in both military and civilian medicine,which could enhance radiosensitivity of various tumors.However,little information is available regarding the effects of UTMD on radiotherapy for glioblastoma or the underlying mechanism.This study aimed to delineate the effect of UTMD on the radiosensitivity of glioblastoma and the potential involvement of autophagy.Methods:GL261,U251 cells and orthotopic glioblastoma-bearing mice were treated with ionizing radiation(IR) or IR plus UTMD.Autophagy was observed by confocal microscopy and transmission electron microscopy.Western blotting and immunofluorescence analysis were used to detect progesterone receptor membrane component 1(PGRMC1),light chain 3 beta 2(LC3B2) and sequestosome 1(SQSTM1/p62) levels.Lentiviral vectors or siRNAs transfection,and fluorescent probes staining were used to explore the underlying mechanism.Results:UTMD enhanced the radiosensitivity of glioblastoma in vitro and in vivo(P<0.01).UTMD inhibited autophagic flux by disrupting autophagosome-lysosome fusion without impairing lysosomal function or autophagosome synthesis in IR-treated glioblastoma cells.Suppression of autophagy by 3-methyladenine,bafilomycin A1 or ATG5 siRNA had no significant effect on UTMD-induced radiosensitization in glioblastoma cells(P<0.05).Similar results were found when autophagy was induced by rapamycin or ATG5 overexpression(P>0.05).Furthermore,UTMD inhibited PGRMC1expression and binding with LC3B2 in IR-exposed glioblastoma cells(P<0.01).PGRMC1 inhibitor AG-205 or PGRMC1siRNA pretreatment enhanced UTMD-induced LC3B2 and p62 accumulation in IR-exposed glioblastoma cells,thereby promoting UTMD-mediated radiosensitization(P<0.05).Moreover,PGRMC1 overexpression abolished UTMD-caused blockade of autophagic degradation,subsequently inhibiting UTMD-induced radiosensitization of glioblastoma cells.Finally,compared with IR plus UTMD group,PGRMC1 overexpression significantly increased tumor size [(3.8±1.1) mm^(2)vs.(8.0±1.9) mm^(2),P<0.05] and decreased survival time [(67.2±2.6) d vs.(40.0±1.2) d,P=0.0026] in glioblastoma-bearing mice.Conclusions:UTMD enhanced the radiosensitivity of glioblastoma partially by disrupting PGRMC1-mediated autophagy.展开更多
PCDD/Fs have been become a serious issue because of their toxicological effects and associated adverse health implications. In this study, the gliding arc plasma was tested for treatment of polychlorinated dibenzo-p-d...PCDD/Fs have been become a serious issue because of their toxicological effects and associated adverse health implications. In this study, the gliding arc plasma was tested for treatment of polychlorinated dibenzo-p-dioxins （PCDDs） and polychlorinated dibenzofurans （PCDFs）, which was synthesized from pentachlorophenol in atmospheric condition at 350℃ with or without the catalysis of CuCl2. From the experiment, we found that the destruction efficiency of PCDD/F homologues after gliding was discharge ranged from 25% to 79%. This result demonstrates that gliding arc plasma is an effective technology to decompose PCDDs/Fs in flue gas. A plausible degradation mechanism for PCDD/Fs by gliding arc was discussed. Finally, a multistage reactor structure of gliding arc was proposed to upgrade removal efficiency for PCDD/Fs.展开更多
Efficient destruction of cyanide by thermal decomposition with ferric oxide addition was proposed. The mechanism of destruction of sodium cyanide with or without ferric oxide addition under various conditions was exam...Efficient destruction of cyanide by thermal decomposition with ferric oxide addition was proposed. The mechanism of destruction of sodium cyanide with or without ferric oxide addition under various conditions was examined by XRD, DSC-TG, and chemical analysis technologies. In the absence of ferric oxide, sodium cyanide decomposes at 587.4 ℃ in air and 879.2 ℃ in argon atmosphere. In the presence of ferric oxide, about 60% of sodium cyanide decomposes at 350 ℃ for 30 min in argon, while almost all sodium cyanide decomposes within 30 min in air or O2 with mass ratio of ferric oxide to sodium cyanide of 1:1. The increase of ferric oxide addition, temperature, and heating time facilitates the destruction of sodium cyanide. It is believed that with ferric oxide addition, NaCN reacts with Fe2O3 to form Na4Fe(CN)6, Na2CO3, NaNO2 and Fe3O4 in argon. NaCN decomposes into NaCNO, Na4Fe(CN)6, minor NaNO2, and the formed NaCNO and Na4Fe(CN)6 further decompose into Na2CO3, CO2, N2, FeOx, and minor NOx in air or O2.展开更多
Many factors can induce rock burst. Shock energy and shock distance are two key factors affecting rock burst. The 32101 roadway of the Xingcun coal mine, which has a tendency for rock burst, was used as an example. Th...Many factors can induce rock burst. Shock energy and shock distance are two key factors affecting rock burst. The 32101 roadway of the Xingcun coal mine, which has a tendency for rock burst, was used as an example. The dynamic module of Itasca’s FLAC (Fast Lagrangian Analysis of Continua) 2D explicit finite-difference software was used to simulate the roadway’s destruction. The vibration velocity and displacements of the rock surrounding the roadway were modeled for different shock energies and hypocenter distances. The simulation results indicate that the vibration velocity and displacement of rock surrounding the roadway have a quadratic relationship to the shock energy and a power law relationship to the distance of the hypocenter from the roadway. A dynamic view of the process was obtained from a series of "snap-shots" collected at 100 different time steps. This shows an isolating "river" is first formed at the hypocenter. The region above the "river" is a low stress zone while below the "river" a high stress zone exists. This high stress zone surrounds the ribs of the roadway in a "double ear" pattern. Continuous and repeated action of the high stress in the "double ear" shaped zone destroys the roadway.展开更多
The destruction of methylphosphonic acid （MPA）, a final product by hydrolysis/neutralization of organophosphorus agents such as sarin and VX （O-ethyl S-[2-（diisopropylamino）ethyl] methylphosphonothionate）, was i...The destruction of methylphosphonic acid （MPA）, a final product by hydrolysis/neutralization of organophosphorus agents such as sarin and VX （O-ethyl S-[2-（diisopropylamino）ethyl] methylphosphonothionate）, was investigated in a a bench-scale, continuous concentric vertical double wall reactor under supercritical water oxidation condition. The experiments were conducted at a temperature range of 450–600°C and a fixed pressure of 25 MPa. Hydrogen peroxide was used as an oxidant. The destruction efficiency （DE） was monitored by analyzing total organic carbon （TOC） and MPA concentrations using ion chromatography on the liquid effluent samples. The results showed that the DE of MPA up to 99.999% was achieved at a reaction temperature of 600°C, oxygen concentration of 113% storichiometric requirement, and reactor residence time of 8 sec. On the basis of the data derived from experiments, a global kinetic rate equation for the DE of MPA and DE of TOC were developed by nonlinear regression analysis. The model predictions agreed well with the experimental data.展开更多
The changes of crosslinking network of perfluorinated elastomer(FFKM)cured by TAIC and DBPH under thermo-oxidative aging conditions were investigated.Two competitive processes including post-curing and network destruc...The changes of crosslinking network of perfluorinated elastomer(FFKM)cured by TAIC and DBPH under thermo-oxidative aging conditions were investigated.Two competitive processes including post-curing and network destruction occur simultaneously,which directly affect the storage modulus and crosslinking density.With the increase of aging temperature,the network destruction becomes dominant.FTIR and XPS characterizations further reveal that the network destruction happens preferentially on the crosslink points of TAIC structure,and the post-curing is mainly caused by the decomposition of residual curing agent DBPH.Unlike the easier breaking of TAIC structure in the crosslinking network,both the backbone and the pendent groups of FFKM itself are much more stable.To further figure out the destruction mechanism,TGAFTIR-GC-MS test was also conducted and a schematic degradation process of TAIC structure was proposed.It is found that the destruction of TAIC crosslinking points happens first on the unstable exocyclic C―N bonds and the intermediate ring radicals could eventually decompose into volatile hydrogen isocyanate(HCNO)under extreme condition.展开更多
In this study, we examined the effects of neuroglobin gene （Ngb） transfection into SH-SY5Y cells, using ultrasound-targeted microbubble destruction （UTMD）, on cobalt chloride-induced hypoxia. With an ultrasound in...In this study, we examined the effects of neuroglobin gene （Ngb） transfection into SH-SY5Y cells, using ultrasound-targeted microbubble destruction （UTMD）, on cobalt chloride-induced hypoxia. With an ultrasound intensity of 0.8 W/cm2, a 60-second exposure duration, 50% duty cycle, and 20% microbubble concentration, pAcGFP1-C1-Ngb-transfected cells exhibited the highest cell viability and transfection efficiency. The efficiency of plasmid delivery was significantly higher with UTMD than transfection with plasmid alone, transfection with plasmid using microbubbles, or transfection of plasmid by ultrasound. In addition, during cobalt chloride-induced hypoxia, caspase-3 activity in pAcGFP1-C1-Ngb-transfected cells was significantly lower than in untransfected cells. Ngb protein and mRNA expression were significantly higher in cells transfected by UTMD than in cells transfected with the other methods. These results demonstrate that UTMD can very efficiently mediate exogenous gene delivery, and that Ngb overexpression protects cells against cobalt chloride-induced hypoxia.展开更多
Osteoarthritis （OA） is a degenerative joint disease and a major cause of pain and disability in older adults. We have previously identified epidermal growth factor receptor （EGFR） signaling as an important regulat...Osteoarthritis （OA） is a degenerative joint disease and a major cause of pain and disability in older adults. We have previously identified epidermal growth factor receptor （EGFR） signaling as an important regulator of cartilage matrix degradation during epiphyseal cartilage development. To study its function in OA progression, we performed surgical destabilization of the medial meniscus （DMM） to induce OA in two mouse models with reduced EGFR activity, one with genetic modification （, was/＋ mice） and the other one with pharmacological inhibition （gefitinib treatment）. Histological analyses and scoring at 3 months post-surgery revealed increased cartilage destruction and accelerated OA progression in both mouse models. TUNEL staining demonstrated that EGFR signaling protects chondrocytes from OA-induced apoptosis, which was further confirmed in primary chondrocyte culture. Immunohistochemistry showed increased aggrecan degradation in these mouse models, which coincides with elevated amounts of ADAMTS5 and matrix metalloproteinase 13 （MMP13）, the principle proteinases responsible for aggrecan degradation, in the articular cartilage after DMM surgery. Furthermore, hypoxia-inducible factor 2α （HIF2α）, a critical catabolic transcription factor stimulating MMP13 expression during OA, was also upregulated in mice with reduced EGFR signaling. Taken together, our findings demonstrate a primarily protective role of EGFR during OA progression by regulating chondrocyte survival and cartilage degradation.展开更多
基金supported by the National Natural Science Foundation of China Nos.82370983,81671015(X.W.),82230030(Y.L.),82101043(S.C.)and 82370922(Y.F.)Beijing International Science and Technology Cooperation Project No.Z221100002722003(Y.L.)+4 种基金Beijing Natural Science Foundation Nos.L234017,JL23002(Y.L.),No.7242282(S.C.)and 7232217(Y.G.)Clinical Medicine Plus X-Young Scholars Project of Peking University No.PKU2024LCXQ039(Y.L.)National Program for Multidisciplinary Cooperative Treatment on Major Diseases No.PKUSSNMP-202013(X.W.)Hygiene and Health Development Scientific Research Fostering Plan of Haidian District Beijing No.HP2023-12-509001(J.Z.)Young Clinical Research Fund of the Chinese Stomatological Association No.CSA-02022-03(J.Z.).
文摘Temporomandibular joint(TMJ)disc displacement is one of the most significant subtypes of temporomandibular joint disorders,but its etiology and mechanism are poorly understood.In this study,we elucidated the mechanisms by which destruction of inflamed collagen fibrils induces alterations in the mechanical properties and positioning of the TMJ disc.By constructing a rat model of TMJ arthritis,we observed anteriorly dislocated TMJ discs with aggravated deformity in vivo from five weeks to six months after a local injection of Freund’s complete adjuvant.By mimicking inflammatory conditions with interleukin-1 beta in vitro,we observed enhanced expression of collagen-synthesis markers in primary TMJ disc cells cultured in a conventional two-dimensional environment.In contrast,three-dimensional(3D)-cultivated disc cell sheets demonstrated the disordered assembly of inflamed collagen fibrils,inappropriate arrangement,and decreased Young’s modulus.Mechanistically,inflammation-related activation of the nuclear factor kappa-B(NF-κB)pathway occurs during the progression of TMJ arthritis.NF-κB inhibition reduced the collagen fibril destruction in the inflamed disc cell sheets in vitro,and early NF-κB blockade alleviated collagen degeneration and dislocation of the TMJ discs in vivo.Therefore,the NF-κB pathway participates in the collagen remodeling in inflamed TMJ discs,offering a potential therapeutic target for disc displacement.
基金supported by the National Natural Science Foundation of China (Nos.21906087 and 52070168)the Key R&D Plan of Zhejiang Province (No.2023C03127)the Fundamental Research Funds for the Central Universities (No.226-2022-00150).
文摘Catalytic destruction is an ascendant technology for the abatement of volatile organic compounds(VOCs)originating fromsolvent-based industrial processes.The varied composition tends to influence each VOC’s catalytic behavior in the reaction mixture.We investigated the catalytic destruction of multi-component VOCs including dichloromethane(DCM)and ethyl acetate(EA),as representatives from pharmaceutical waste gases,over co-supported HxPO_(4)-RuOx/CeO_(2) catalyst.A mutual inhibitory effect relating to concentrations because of competitive adsorption was verified in the binary VOCs oxidation and EA posed a more negative effect on DCM oxidation owing to EA’s superior adsorption capacity.Preferential adsorption of EA on acidic sites(HxPO_(4)/CeO_(2))promoted DCM activation on basic sites(O^(2−))and the dominating EA oxidation blocked DCM’s access to oxidation centers(RuOx/CeO_(2)),resulting in boosted monochloromethane yield and increased chlorine deposition for DCM oxidation.The impaired redox ability of Ru species owing to chlorine deposition in turn jeopardized deep oxidation of EA and its by-products,leading to increased gaseous by-products such as acetic acid originating fromEA pyrolysis.Notably,DCM at low concentration slightly promoted EA conversion at low temperatures with or without water,consistent with the enhanced EA adsorption in co-adsorption analyses.This was mainly due to that DCM impeded the shielding effect of hydrolysate deposition from rapid EA hydrolysis depending on the decreased acidity.Moreover,water benefited EA hydrolysis but decreased CO_(2) selectivity while the generated water derived from EA was likely to affect DCM transformation.This work may provide theoretical guidance for the promotion of applied catalysts toward industrial applications.
基金supported by the National Natural Science Foundation of China(No.2021YFC3200603)the Special Research Assistant Program,Chinese Academy of Sciences.
文摘Photocatalytic disinfection is an eco-friendly strategy for countering bacterial pollution in aquatic environments.Numerous strategies have been devised to facilitate the generation of reactive oxygen species(ROS)within photocatalysts,ultimately leading to the eradication of bacteria.However,the significance of the physical morphology of photocatalysts in the context of sterilization is frequently obscured,and the progress in the development of physical-chemical synergistic sterilization photocatalysts has been relatively limited.Herein,graphitic carbon nitride(g-C_(3)N_(4))is chemically protonated to expose more sharp edges.PL fluorescence and EIS results indicate that the protonation can accelerate photogenerated carrier separation and enhance ROS production.Meanwhile,the sharp edges on the protonated g-C_(3)N_(4)facilitate the physical disruption of cell walls for further promoting oxidative damage.Protonated C_(3)N_(4)demonstrated superior bactericidal performance than that of pristine g-C_(3)N_(4),effectively eliminating Escherichia coli within 40 minutes under irradiation.This work highlights the significance of incorporating physical and chemical synergies in photocatalyst design to enhance the disinfection efficiency of photocatalysis.
文摘Dear Editor,I am Yuki Tanaka from Hakodate Central General Hospital,Japan.Mikulicz’s disease is characterized by symmetrical swelling of lacrimal and salivary glands.In 2012,a Japanese study group proposed comprehensive diagnostic criteria for immunoglobulin G4-related disease(IgG4-RD)^([1]).They have revealed that Mikulicz’s disease is a systemic IgG4-RD and attracted attentions of ophthalmologists.In 2014,the criteria for IgG4-related ophthalmic disease(IgG4-ROD)were established.
文摘BACKGROUND Although laparoscopic gastrolithotomy had been widely used in clinical practice,uncommon postoperative complications still require vigilance by medical staff.CASE SUMMARY Here we report a 67-year-old man who suffered for 18 months and underwent surgery several times due to a rare and undetected complication of laparoscopic gastricolithotomy.He presented to multiple hospitals because of sustained left upper quadrant abdominal pain one month after laparoscopic gastricolithotomy due to a large gastric bezoar caused by unrestrained eating of black dates and was diagnosed with possible intercostal neuritis.Many painkillers were used to relieve his symptoms but the condition progressed.Seven months after surgery,he was hospitalized as skin ulceration occurred in the left upper abdominal wall and was subsequently diagnosed with a massive thoracoabdominal wall abscess.One year after surgery,irreversible costal destruction was demonstrated.Both lesions were finally proved to be secondary damage due to a rare chronic gastro-abdominal wall fistula related to laparoscopic gastricolithotomy and the diameter of the gastric fistula reached 2 centimeters(cm).The patient was ultimately cured but underwent multi-regional incisions and drainage of the abscess,drainage of the gastric fistula,partial gastrectomy and removal of damaged ribs,and was followed-up for more than 4 years without recurrence.It is well-known that gastric fistula usually has an acute onset and occurs early after surgery,while chronic gastro-abdominal wall fistula especially with secondary massive thoracoabdominal wall abscess and costal destruction has rarely been reported.CONCLUSION This may be the first reported case of a chronic thoracoabdominal abscess and costal destruction caused by an undetected chronic gastro-abdominal wall fistula.We believe that this is a novel type of gastric fistula and the diagnosis and treatment were challenging.
基金supported by the Researchers Supporting Project of King Saud University,Riyadh,Saudi Arabia,under Project RSPD2025R681。
文摘With the continuous advancement of communication and unmanned aerial vehicle(UAV)technologies,the collaborative operations of diverse platforms,including UAVs and ground vehicles,have been significantly promoted.However,battlefield uncertainties,such as equipment failures and enemy attacks,can impact these collaborative operations'stability and communication efficiency.To this end,we design a highly destruction-resistant air-ground cooperative resilient networking platform that aims to enhance the robustness of network communications by integrating ground vehicle information for UAV network deployment.It then incorporates the concept of virtual guiding force,enabling the UAV swarm to adaptively configure its network layout based on ground vehicle information,thereby improving network destruction resistance.Simulation results demonstrate that the UAV swarm involved in the proposed platform exhibits balanced flight energy consumption and excellent performance in network destruction resistance.
文摘In order to improve the destruction efficiency of dioxins and also for developing new dioxin control technology, the destruction mechanisms of 2,3,7,8-tetrachlorodihenzo-p-dioxin （2,3,7,8-TCDD） by O3 and NO3, were investigated employing quantum chemical calculations. For involved reactions, the microcosmic reaction processes were analyzed and depicted in detail based on geometry optimizations made by the B3LYP/6-31G（d） method. At the same time, the reaction activation energies were also calculated at the MP2/6- 311G（d,p）//B3LYP/6-31G（d） level. Configuration analysis indicated that 2,3,7,8-TCDD could be destroyed by 03 and NO3 in two different ways. The destruction of 2,3,7,8-TCDD by 03 proceeded via the addition of 03 and the cleavage of C=C while the destruction of 2,3,7,8-TCDD by NO3 proceeded via the substitution of chlorine by NO3. Calculated results show that, the activation energy of the destruction reaction of 2,3,7,8-TCDD by NO3 （267.48 kJ/mol） is much larger than that of the destruction reaction of 2,3,7,8-TCDD by O3 （51.20 kJ/mol）. This indicated that the destruction of 2,3,7,8-TCDD by 03 is much more efficient than that of 2,3,7,8-TCDD by NO3. The reason why the activation energy for the destruction reaction of 2,3,7,8-TCDD by NO3 is so large, is also discussed.
文摘We aimed to investigate the synergistic effects of ultrasonic waves and repeated freeze-thaw cycles on cel-wal destruction of Auricularia auric-ula mycelia, and determine the best combination of conditions for cel-wal destruc-tion of Auricularia auricula mycelia. [Method] The effects of destruction time, added water, destruction times, freeze time and number of freeze-thaw cycles during ultra-sonic treatment on polysaccharide yield were investigated by single-factor test in our research. The optimum conditions for cel-wal destruction of Auricularia auricula mycelia by the synergistic effect of ultrasonic waves and repeated freeze-thaw cycles were ascertained by orthogonal test. [Result] The results of single test indicated the best combination of conditions was as fol ows： freeze time, 30 min; destruction time, 20 min; added water, 15 times; destruction times, 2 times; number of freeze-thaw cycles, 3 cycles. The results of orthogonal test indicated the influencing factors ranked as destruction time 〉 destruction times 〉 freeze time. The best combination of conditions was as fol ows： freeze time, 30 min; destruction time, 25 min; destruc-tion times, 2 times. Under above conditions, the polysaccharide yield reached 57.76 mg/g. [Conclusion] This research would provide a basis and reference for practical production.
基金This work was financially supported by the National Key R&D Program of China(No.2016YFC0600109)the State Key Laboratory of Lithospheric Evolution,IGGCAS(No.SKL-Z201905)+1 种基金This work was also financially supported by the National Natural Science Foundation of China(No.41602099)the State Key Laboratory of Lithospheric Evolution,IGGCAS(No.SPECIAL201606).
文摘The North China Craton(NCC)is the best example of an Archean craton that has lost its stability in the Late Mesozoic.Although the cratonic destruction is generally considered to have occurred in the Eastern Block and reached a peak in the Early Cretaceous,the exact areal extent of cratonic destruction is debated,especially the southern and northern margin of the NCC.Here we report geochronology,geochemical and Hf isotopic data of the Late Mesozoic granitoids from Lushi polymetal mineralization area(LPMA)in the southern margin of NCC.These results provide new insights into the destruction in the southern margin of the NCC during the Late Mesozoic.Zircon U-Pb dating indicates that eight granitoids intruded in the Late Jurassic to Early Cretaceous(136.8–154.1 Ma),respectively.Geochemical signatures define these granitoids being A-type or I-type granite that formed in an extension setting.In addition,Hf isotopic compositions of zircons from these granitoids vary in a relatively large range,withεHf(t)values and TDM2 ages ranginge from-26.1 to+15.2 and 215 to 2849 Ma,respectively.The parental magmas were likely derived from diverse sources,including materials of the partial melting of ancient lower crust and mantle-derived mafic magmas in various proportions.Combining with previous studies on the contemporaneous magma-tectonic activities in circum of NCC,we suggest that the rim of NCC was already unstabilized from the Late Jurassic in the LPMA.The subduction of the Paleo-Pacific Plate was the main trigger to the destruction of the southern margin of NCC,which was responsible for the lithospheric extension and thinning,extensive magmatism and mineralization.
文摘[Objective]To investigate the inhibitory effect ofhonokiol on Candida albicans in vitro.[Methods]The minimum inhibitory concentration(MIC)and minimum fungicidal concentration(MFC)of magnolol for C.albicans were determined by microdilution method.Transmission electron microscopy was used to examine the effect of different concentrations of honokiol on the ultrastructure of C.albicans.Apoptosis of C.albicans caused by honokiol was analyzed by Annexin V-FITC/propidium iodide(PI)double staining and the accumulation of reactive oxygen species(ROS)in C.albicans cells was determined by DCFH-DA staining.The effects of honokiol on mitochondrial membrane potential and cell membrane permeability of C.albicans were analyzed by JC-1 staining and PI staining respectively.[Results]Honokiol had strong inhibitory effect on C.albicans,with MIC90 of 16μg/mL and MFC of 32μg/mL.Honokiol affected cell wall,cell membrane,and cytoplasm of C.albicans,induced both apoptosis and necrosis in C.albicans,probably through ROS production and disruption of mitochondrial function.It also changed the permeability of cell membrane,leaded to the cell wall damage and the binding of ergosterol.[Conclusion]Inhibition of C.albicans by honikiol involves multiple mechanisms including ROS production accompanied by a series of cellular damages.Honikiol appears to be a potential antifungal drug candidate.
基金supported by the Exploratory Research Program of Petrochemical Research Institute,PetroChina~~
文摘A series of zeolites,including USY zeolites without sodium,Na-USY at different Na contents,La-USY with different rare earth（RE） contents and La-Na-USY with RE and Na were prepared by an ion exchange method.They were investigated to understand the activation barriers for the destruction of Y zeolite structure under hydrothermal treatment and the effect of V using the solid-state kinetic model.The results showed that the pathways for Y zeolite destruction were dealumination,desiliconization and the disappearance of La-O bonds.Zeolites were destroyed by steam through acid hydrolysis,which was accelerated by V.In addition,Na and V exerted a synergistic effect on the framework destruction,and the formation of NaOH was the rate-determining step.The presence of RE elements decreased hydrolysis and stabilized the structure of the zeolites.The interaction between V and RE destroyed zeolite structure by eliminating the stabilizing La-O[RE-OH-RE]^（5＋）bridges in the sodalite cages.
文摘AIM： To detect the therapeutic effects of chemical destruction of celiac ganglion in patients with pancreatic carcinoma with intractable pain. METHODS： Ninety-seven cases with advanced pancreatic carcinoma received chemical destruction of celiac ganglion-5 mL pure alcohol injection around celiac artery under ultrasonic guidance. The changes of visual analogue scale （VAS）, serum substance P （Sub P）, β-endopeptide （β-EP） and T-lymphocyte subtypes level were compared between pre- and post-therapy. RESULTS： Successful rate of puncture was 98.7%, with one failure. No serious complications such as traumatic pancreatitis, pancreatic fistula, abdominal cavity hemorrhage or peritoneal infection occurred. VAS, serum Sub P and β-EP level significantly changed after treatment （8.0 ± 2.3 vs 4.6 ± 2.1, 254.1 ± 96.7 vs 182.4 ± 77.6, 3.2 ± 0.8 vs 8.8 ± 2.1, P 〈 0.01, P 〈 0.05, P 〈 0.01） with complete relief rate 54.2%, partial relief rate 21.9%, ineffective rate 12.5% and recurrent rate 10.7%. The T-lymphocyte subtypes level remarkably increased when compared with that of pre-therapy （46.7 ± 3.7 vs 62.5 ± 5.5, P 〈 0.01）. CONCLUSION： Our study suggests that chemical destruction of celiac ganglion under ultrasonic guidance is highly safe, and can evidently relieve cancer pain and improve the cellular immunity in patients with advanced pancreatic carcinoma.
基金supported by the National Natural Science Foundation of China (82073544 and 81971774)the Chongqing Talent Project (CQYC2019)the Chongqing Chief Expert Program in Medicine (CQYC2018)。
文摘Background:Ultrasound-triggered microbubble destruction(UTMD) is a widely used noninvasive technology in both military and civilian medicine,which could enhance radiosensitivity of various tumors.However,little information is available regarding the effects of UTMD on radiotherapy for glioblastoma or the underlying mechanism.This study aimed to delineate the effect of UTMD on the radiosensitivity of glioblastoma and the potential involvement of autophagy.Methods:GL261,U251 cells and orthotopic glioblastoma-bearing mice were treated with ionizing radiation(IR) or IR plus UTMD.Autophagy was observed by confocal microscopy and transmission electron microscopy.Western blotting and immunofluorescence analysis were used to detect progesterone receptor membrane component 1(PGRMC1),light chain 3 beta 2(LC3B2) and sequestosome 1(SQSTM1/p62) levels.Lentiviral vectors or siRNAs transfection,and fluorescent probes staining were used to explore the underlying mechanism.Results:UTMD enhanced the radiosensitivity of glioblastoma in vitro and in vivo(P<0.01).UTMD inhibited autophagic flux by disrupting autophagosome-lysosome fusion without impairing lysosomal function or autophagosome synthesis in IR-treated glioblastoma cells.Suppression of autophagy by 3-methyladenine,bafilomycin A1 or ATG5 siRNA had no significant effect on UTMD-induced radiosensitization in glioblastoma cells(P<0.05).Similar results were found when autophagy was induced by rapamycin or ATG5 overexpression(P>0.05).Furthermore,UTMD inhibited PGRMC1expression and binding with LC3B2 in IR-exposed glioblastoma cells(P<0.01).PGRMC1 inhibitor AG-205 or PGRMC1siRNA pretreatment enhanced UTMD-induced LC3B2 and p62 accumulation in IR-exposed glioblastoma cells,thereby promoting UTMD-mediated radiosensitization(P<0.05).Moreover,PGRMC1 overexpression abolished UTMD-caused blockade of autophagic degradation,subsequently inhibiting UTMD-induced radiosensitization of glioblastoma cells.Finally,compared with IR plus UTMD group,PGRMC1 overexpression significantly increased tumor size [(3.8±1.1) mm^(2)vs.(8.0±1.9) mm^(2),P<0.05] and decreased survival time [(67.2±2.6) d vs.(40.0±1.2) d,P=0.0026] in glioblastoma-bearing mice.Conclusions:UTMD enhanced the radiosensitivity of glioblastoma partially by disrupting PGRMC1-mediated autophagy.
基金Project supported by the National Natural Science Foundation of China(No.50476058)Natural Science Foundation of Zhejiang Province(No.X506214)
文摘PCDD/Fs have been become a serious issue because of their toxicological effects and associated adverse health implications. In this study, the gliding arc plasma was tested for treatment of polychlorinated dibenzo-p-dioxins （PCDDs） and polychlorinated dibenzofurans （PCDFs）, which was synthesized from pentachlorophenol in atmospheric condition at 350℃ with or without the catalysis of CuCl2. From the experiment, we found that the destruction efficiency of PCDD/F homologues after gliding was discharge ranged from 25% to 79%. This result demonstrates that gliding arc plasma is an effective technology to decompose PCDDs/Fs in flue gas. A plausible degradation mechanism for PCDD/Fs by gliding arc was discussed. Finally, a multistage reactor structure of gliding arc was proposed to upgrade removal efficiency for PCDD/Fs.
基金financial supports from the National Key R&D Program of China (2018YFC0604604)the National Natural Science Foundation of China-Yunnan Joint Fund (U1702252)+1 种基金the Fundamental Research Funds for Central Universities of China (N182506003)the Key Scientific Research Project of Liaoning Province,China (2019JH2/10300051)。
文摘Efficient destruction of cyanide by thermal decomposition with ferric oxide addition was proposed. The mechanism of destruction of sodium cyanide with or without ferric oxide addition under various conditions was examined by XRD, DSC-TG, and chemical analysis technologies. In the absence of ferric oxide, sodium cyanide decomposes at 587.4 ℃ in air and 879.2 ℃ in argon atmosphere. In the presence of ferric oxide, about 60% of sodium cyanide decomposes at 350 ℃ for 30 min in argon, while almost all sodium cyanide decomposes within 30 min in air or O2 with mass ratio of ferric oxide to sodium cyanide of 1:1. The increase of ferric oxide addition, temperature, and heating time facilitates the destruction of sodium cyanide. It is believed that with ferric oxide addition, NaCN reacts with Fe2O3 to form Na4Fe(CN)6, Na2CO3, NaNO2 and Fe3O4 in argon. NaCN decomposes into NaCNO, Na4Fe(CN)6, minor NaNO2, and the formed NaCNO and Na4Fe(CN)6 further decompose into Na2CO3, CO2, N2, FeOx, and minor NOx in air or O2.
基金Projects 50490270, 50474068, 50674085 supported by the National Natural Science Foundation of China 2005CB221504 by the National Key FoundationResearch Program of China+2 种基金2006BAK04B02, 2006BAK03B06 by the National Science Program of China NCET-06-0478 by the Ministry of Education New Century Outstanding Person Programming of China2006B002 by the Science Foundation of China University of Mining and Technology
文摘Many factors can induce rock burst. Shock energy and shock distance are two key factors affecting rock burst. The 32101 roadway of the Xingcun coal mine, which has a tendency for rock burst, was used as an example. The dynamic module of Itasca’s FLAC (Fast Lagrangian Analysis of Continua) 2D explicit finite-difference software was used to simulate the roadway’s destruction. The vibration velocity and displacements of the rock surrounding the roadway were modeled for different shock energies and hypocenter distances. The simulation results indicate that the vibration velocity and displacement of rock surrounding the roadway have a quadratic relationship to the shock energy and a power law relationship to the distance of the hypocenter from the roadway. A dynamic view of the process was obtained from a series of "snap-shots" collected at 100 different time steps. This shows an isolating "river" is first formed at the hypocenter. The region above the "river" is a low stress zone while below the "river" a high stress zone exists. This high stress zone surrounds the ribs of the roadway in a "double ear" pattern. Continuous and repeated action of the high stress in the "double ear" shaped zone destroys the roadway.
基金supported by Agency for Defense Development,Korea and Korea Institute of Scienceand Technology
文摘The destruction of methylphosphonic acid （MPA）, a final product by hydrolysis/neutralization of organophosphorus agents such as sarin and VX （O-ethyl S-[2-（diisopropylamino）ethyl] methylphosphonothionate）, was investigated in a a bench-scale, continuous concentric vertical double wall reactor under supercritical water oxidation condition. The experiments were conducted at a temperature range of 450–600°C and a fixed pressure of 25 MPa. Hydrogen peroxide was used as an oxidant. The destruction efficiency （DE） was monitored by analyzing total organic carbon （TOC） and MPA concentrations using ion chromatography on the liquid effluent samples. The results showed that the DE of MPA up to 99.999% was achieved at a reaction temperature of 600°C, oxygen concentration of 113% storichiometric requirement, and reactor residence time of 8 sec. On the basis of the data derived from experiments, a global kinetic rate equation for the DE of MPA and DE of TOC were developed by nonlinear regression analysis. The model predictions agreed well with the experimental data.
基金financial support from the National Natural Science Foundation of China (No. 51721091)the financial supports from the National Natural Science Foundation of China (Nos. 51873125 and 52073184)Research Foundation (International Program) of Science and Technology Department of Sichuan Province (No. 2019YFH0027)
文摘The changes of crosslinking network of perfluorinated elastomer(FFKM)cured by TAIC and DBPH under thermo-oxidative aging conditions were investigated.Two competitive processes including post-curing and network destruction occur simultaneously,which directly affect the storage modulus and crosslinking density.With the increase of aging temperature,the network destruction becomes dominant.FTIR and XPS characterizations further reveal that the network destruction happens preferentially on the crosslink points of TAIC structure,and the post-curing is mainly caused by the decomposition of residual curing agent DBPH.Unlike the easier breaking of TAIC structure in the crosslinking network,both the backbone and the pendent groups of FFKM itself are much more stable.To further figure out the destruction mechanism,TGAFTIR-GC-MS test was also conducted and a schematic degradation process of TAIC structure was proposed.It is found that the destruction of TAIC crosslinking points happens first on the unstable exocyclic C―N bonds and the intermediate ring radicals could eventually decompose into volatile hydrogen isocyanate(HCNO)under extreme condition.
文摘In this study, we examined the effects of neuroglobin gene （Ngb） transfection into SH-SY5Y cells, using ultrasound-targeted microbubble destruction （UTMD）, on cobalt chloride-induced hypoxia. With an ultrasound intensity of 0.8 W/cm2, a 60-second exposure duration, 50% duty cycle, and 20% microbubble concentration, pAcGFP1-C1-Ngb-transfected cells exhibited the highest cell viability and transfection efficiency. The efficiency of plasmid delivery was significantly higher with UTMD than transfection with plasmid alone, transfection with plasmid using microbubbles, or transfection of plasmid by ultrasound. In addition, during cobalt chloride-induced hypoxia, caspase-3 activity in pAcGFP1-C1-Ngb-transfected cells was significantly lower than in untransfected cells. Ngb protein and mRNA expression were significantly higher in cells transfected by UTMD than in cells transfected with the other methods. These results demonstrate that UTMD can very efficiently mediate exogenous gene delivery, and that Ngb overexpression protects cells against cobalt chloride-induced hypoxia.
基金supported by ASBMR Research Career Enhancement Award (to LQ)NIH grants AR060991 (to LQ)AR062908 (to ME-I)
文摘Osteoarthritis （OA） is a degenerative joint disease and a major cause of pain and disability in older adults. We have previously identified epidermal growth factor receptor （EGFR） signaling as an important regulator of cartilage matrix degradation during epiphyseal cartilage development. To study its function in OA progression, we performed surgical destabilization of the medial meniscus （DMM） to induce OA in two mouse models with reduced EGFR activity, one with genetic modification （, was/＋ mice） and the other one with pharmacological inhibition （gefitinib treatment）. Histological analyses and scoring at 3 months post-surgery revealed increased cartilage destruction and accelerated OA progression in both mouse models. TUNEL staining demonstrated that EGFR signaling protects chondrocytes from OA-induced apoptosis, which was further confirmed in primary chondrocyte culture. Immunohistochemistry showed increased aggrecan degradation in these mouse models, which coincides with elevated amounts of ADAMTS5 and matrix metalloproteinase 13 （MMP13）, the principle proteinases responsible for aggrecan degradation, in the articular cartilage after DMM surgery. Furthermore, hypoxia-inducible factor 2α （HIF2α）, a critical catabolic transcription factor stimulating MMP13 expression during OA, was also upregulated in mice with reduced EGFR signaling. Taken together, our findings demonstrate a primarily protective role of EGFR during OA progression by regulating chondrocyte survival and cartilage degradation.
