Gastric cancer(GC)is characterized by high morbidity and mortality rates.Chinese agarwood comprises the resin-containing wood of Aquilaria sinensis(Lour.)Gilg.,traditionally utilized for treating asthma,cardiac ischem...Gastric cancer(GC)is characterized by high morbidity and mortality rates.Chinese agarwood comprises the resin-containing wood of Aquilaria sinensis(Lour.)Gilg.,traditionally utilized for treating asthma,cardiac ischemia,and tumors.However,comprehensive research regarding its anti-GC effects and underlying mechanisms remains limited.In this study,Chinese agarwood petroleum ether extract(CAPEE)demonstrated potent cytotoxicity against human GC cells,with half maximal inhibitory concentration(IC_(50))values for AGS,HGC27,and MGC803 cells of 2.89,2.46,and 2.37μg·mL^(−1),respectively,at 48 h.CAPEE significantly induced apoptosis in these GC cells,with B-cell lymphoma-2(BCL-2)associated X protein(BAX)/BCL-2 antagonist killer 1(BAK)likely mediating CAPEE-induced apoptosis.Furthermore,CAPEE induced G_(0)/G_(1)phase cell cycle arrest in human GC cells via activation of the deoxyribonucleic acid(DNA)damage-p21-cyclin D1/cyclin-dependent kinase 4(CDK4)signaling axis,and increased Fe^(2+),lipid peroxides and reactive oxygen species(ROS)levels,thereby inducing ferroptosis.Ribonucleic acid(RNA)sequencing,real-time quantitative polymerase chain reaction(RT-qPCR),and Western blotting analyses revealed CAPEE-mediated upregulation of heme oxygenase-1(HO-1)in human GC cells.RNA interference studies demonstrated that HO-1 knockdown reduced CAPEE sensitivity and inhibited CAPEE-induced ferroptosis in human GC cells.Additionally,CAPEE administration exhibited robust in vivo anti-GC activity without significant toxicity in nude mice while inhibiting tumor cell growth and promoting apoptosis in tumor tissues.These findings indicate that CAPEE suppresses human GC cell growth through upregulation of the DNA damage-p21-cyclin D1/CDK4 signaling axis and HO-1-mediated ferroptosis,suggesting its potential as a candidate drug for GC treatment.展开更多
The effect of Ce, Co, and B on the formation of 1：13 phase in La（Fe, Si）13 alloys was investigated by XRD, SEM and EDS. The results show that Co can improve the formation of 1：13 phase in as-cast LaFe11.6-xCoxSi1....The effect of Ce, Co, and B on the formation of 1：13 phase in La（Fe, Si）13 alloys was investigated by XRD, SEM and EDS. The results show that Co can improve the formation of 1：13 phase in as-cast LaFe11.6-xCoxSi1.4 alloys, but in as-cast and annealed LaFe11.6Si1.4-xCox alloys, it will hamper the formation of 1：13 phase and help the formation of a-Fe（Co, Si） solid solution. Ce2Fel7 phases will form when x reaches a certain value in as-cast and annealed La1-xCexFe11.5Si1.5 alloys. B can improve the formation of 1：13 phase accompanied with Fe2B phase in as-cast LaFe11.6-xBxSi1.4 alloys. B improves the formation of a-Fe solid solution in LaFe11.6Si1.4-xBx alloys, and there is almost only a-Fe in as-cast and annealed LaFe11.6Si0.9B0.5 alloy. In all, the introduction of Co, B, and Ce cannot eliminate the a-Fe phases in corresponding alloys prepared by the high-temperature and short-time annealing process.展开更多
The effects of aging on the microstructure, mechanical properties, intergranular corrosion, and exfoliation corrosion of an Al-3.5Cu-1.5Li-0.22（Sc ＋ Zr） alloy have been investigated. The results show that the alloy...The effects of aging on the microstructure, mechanical properties, intergranular corrosion, and exfoliation corrosion of an Al-3.5Cu-1.5Li-0.22（Sc ＋ Zr） alloy have been investigated. The results show that the alloy has the character of age hardening, and the major phase of precipitation and strengthening is the T1 phase. The aging temperature and aging time have a significant effect on the amount and distribution of the T1 phase. The proper artificial single-aging treatment of the alloy is at 160℃ for 40 h. The intergranular corrosion and exfoliation corrosion of the alloy are caused by the anodic dissolution of the T1 phase and the precipitate-free zone （PFZ）. With increasing the aging time to overaged, the T1 phase coarsens, and the PFZ widens, leading to an increase in the susceptibility to intergranular corrosion and exfoliation corrosion.展开更多
A 1-dodecanethiol-based phase-transfer protocol is developed for the extraction of noble metal ions from aqueous solution to a hydrocarbon phase, which calls for first mixing the aqueous metal ion solution with an eth...A 1-dodecanethiol-based phase-transfer protocol is developed for the extraction of noble metal ions from aqueous solution to a hydrocarbon phase, which calls for first mixing the aqueous metal ion solution with an ethanolic solution of 1-dodecanethiol, and then extracting the coordination compounds formed between noble metal ions and 1-dodecanethiol into a non-polar organic solvent. A number of characterization techniques, including inductively coupled plasma atomic emission spectroscopy, Fourier transform infrared spectroscopy, and thermogravimetric analysis demonstrate that this protocol could be applied to extract a wide variety of noble metal ions from water to dichlorometh- ane with an efficiency of 〉96%, and has high selectivity for the separation of the noble metal ions from other transition metals. It is therefore an attractive alternative for the extraction of noble metals from water, soil, or waste printed circuit boards.展开更多
The precipitation behaviors of an A1-Cu-Li-Mn-Zr alloy at different ageing temperatures （120, 160 and 200 ~C） were investigated using Vickers hardness measurements and transmission electron microscopy （TEM） charac...The precipitation behaviors of an A1-Cu-Li-Mn-Zr alloy at different ageing temperatures （120, 160 and 200 ~C） were investigated using Vickers hardness measurements and transmission electron microscopy （TEM） characterization. Age hardening curves show an increase in precipitation kinetics with increasing ageing temperature. The results of TEM show that for the samples peak aged at 120 ~C, the amount of g＇ （A13Li）, GP zones/0＇ （A12Cu） and Z （A15Cu6Li2） phases is obviously higher than that of T1 （A12CuLi） precipitates; while the samples peak aged at 160 and 200 ~C are usually dominated by T1 phase with a minor fraction of GP zones/0＇ and g＇, and the Z phase almost does not form. In addition, quantitative analysis on the T1 platelets demonstrates that the samples peak aged at 200 ~C have larger plate diameter and smaller area fraction of T1, as compared to the samples peak aged at 160 ~C. Correspondingly, the possible reasons for such phenomena are discussed.展开更多
Abstract Objective To examine UVB-induced responses in normal human keratinocytes （HaCaT） and epidermoid carcinoma cells （A431） at the cellular and molecular level, and investigated the protective effect of salidr...Abstract Objective To examine UVB-induced responses in normal human keratinocytes （HaCaT） and epidermoid carcinoma cells （A431） at the cellular and molecular level, and investigated the protective effect of salidroside. Methods Cells irradiated by UVB at various dosage and their viability was assessed by MTT assays, cell cycle was analysed by flow cytometry. The expression of NF-KB, BCL-2, and CDK6 after 50 J/㎡ UVB irradiation were detected by RT-PCR and western blotting. Results Our results confirmed greater tolerance of A341 cells to UVB-induced damage such as cell viability and cell cycle arrest, which was accompanied by differential expression changes in NF-KB, BCL-2, and CDK6. UVB exposure resulted in HaCaT cells undergoing G1-S phase arrest. When treated with salidroside, HaCaT survival was significantly enhanced following exposure to UVB, suggesting great therapeutic potential for this compound. Conclusion Taken together, our study suggests that A431 respond differently to UVB than norma HaCaT cells, and supports a role for NF-KB, CDK6, and BCL-2 in UVB-induced cell G1-S phase arrest Furthermore, salidroside can effectively protect HaCaT from UVB irradiation.展开更多
Magneli phase titanium sub-oxide conductive ceramic Tin O2n-1 was used as the support for Pt due to its excellent resistance to electrochemical oxidation, and Pt/Tin O2n-1 composites were prepared by the impregnation-...Magneli phase titanium sub-oxide conductive ceramic Tin O2n-1 was used as the support for Pt due to its excellent resistance to electrochemical oxidation, and Pt/Tin O2n-1 composites were prepared by the impregnation-reduction method. The electrochemical stability of Tin O2n-1 was investigated and the results show almost no change in the redox region after oxidation for 20 h at 1.2 V(vs NHE) in 0.5 mol/L H2SO4 aqueous solution. The catalytic activity and stability of the Pt/Tin O2n-1 toward the oxygen reduction reaction(ORR) in 0.5 mol/L H2SO4 solution were investigated through the accelerated aging tests(AAT), and the morphology of the catalysts before and after the AAT was observed by transmission electron microscopy. At the potential of 0.55 V(vs SCE), the specific kinetic current density of the ORR on the Pt/Tin O2n-1 is about 1.5 times that of the Pt/C. The LSV curves for the Pt/C shift negatively obviously with the half-wave potential shifting about 0.02 V after 8000 cycles AAT, while no obvious change takes place for the LSV curves for the Pt/Tin O2n-1. The Pt particles supported on the carbon aggregate obviously, while the morphology of the Pt supported on Tin O2n-1 remains almost unchanged, which contributes to the electrochemical surface area loss of Pt/C being about 2times that of the Pt/Tin O2n-1. The superior catalytic stability of Pt/Tin O2n-1 toward the ORR could be attributed to the excellent stability of the Tin O2n-1 and the electronic interaction between the metals and the support.展开更多
In this work, a new sample pretreatment method prior to HPLC separations was developed for the determination of auxins in plant samples, Owing to its large surface area and high adsorption capacity, multi-walled carbo...In this work, a new sample pretreatment method prior to HPLC separations was developed for the determination of auxins in plant samples, Owing to its large surface area and high adsorption capacity, multi-walled carbon nanotube （MWCNT） was chosen as the adsorbent for the extraction of auxins from plant samples. In this study, two important auxins were selected as model analytes, namely indole-3- butyric acid （IBA） and 1-naphthylacetic acid （NAA）. They could be extracted and concentrated due to their π-π stacking interactions with MWCNT. Then HPLC-UV was introduced to detect IBA and NAA after sample pretreatment. Factors that may affect the enrichment efficiency were investigated and optimized. Comparative studies showed that MWCNT was superior to CI 8 for the extraction of the two analytes. Validation experiments showed that the optimized method had good linearity （0.9998 and 0.9960）, high recovery （81.4%-85.4%）, and low detection limits （0.0030 mg/L and 0.0012 mg/L）. The results indicated that the novel method had advantages of convenience, good sensitivity, high efficiency, and it was feasible for the determination of auxins in plant samples.展开更多
The mechanism of the locking of the E1 Nino event onset phase to boreal spring （from April to June） in an intermediate coupled ocean-atmosphere model is investigated. The results show that the seasonal variation of ...The mechanism of the locking of the E1 Nino event onset phase to boreal spring （from April to June） in an intermediate coupled ocean-atmosphere model is investigated. The results show that the seasonal variation of the zonal wind anomaly over the equatorial Pacific associated with the seasonal variation of the ITCZ is the mechanism of the locking in the model. From January to March of the E1 Nino year, the western wind anomaly over the western equatorial Pacific can excite the downwelling Kelvin wave that propagates eastward to the eastern and middle Pacific by April to June. From April to December of the year before the E1 Nifio year, the eastern wind anomaly over the equatorial Pacific forces the downwelling Rossby waves that modulate the ENSO cycle. The modulation and the reflection at the western boundary modulate the time of the transition from the cool to the warm phase to September of the year before the E1 Nifio year and cause the strongest downwelling Kelvin wave from the reflected Rossby waves at the western boundary to arrive in the middle and eastern equatorial Pacific by April to June of the E1 Nino year. The superposition of these two kinds of downwelling Kelvin waves causes the El Nino event to tend to occur from April to June.展开更多
We theoretically study the quantum Fisher information（QFI） of the SU（1,1） interferometer with phase shifts in two arms by coherent squeezed vacuum state input, and give the comparison with the result of phase shi...We theoretically study the quantum Fisher information（QFI） of the SU（1,1） interferometer with phase shifts in two arms by coherent squeezed vacuum state input, and give the comparison with the result of phase shift only in one arm.Different from the traditional Mach–Zehnder interferometer, the QFI of single-arm case for an SU（1,1） interferometer can be slightly higher or lower than that of two-arm case, which depends on the intensities of the two arms of the interferometer.For coherent squeezed vacuum state input with a fixed mean photon number, the optimal sensitivity is achieved with a squeezed vacuum input in one mode and the vacuum input in the other.展开更多
The microstructure and mechanical behaviors of NiAl-28Cr-5Mo-1Nb eutectic alloy were investigated by using scanning electron microscopy, X-ray diffraction, transmission electron microscopy and compression tests, respe...The microstructure and mechanical behaviors of NiAl-28Cr-5Mo-1Nb eutectic alloy were investigated by using scanning electron microscopy, X-ray diffraction, transmission electron microscopy and compression tests, respectively. The alloy is mainly composed of three phases, which are the gray lamellar Cr（Mo） plate, black NiAI matrix and semicontinuously distributed Cr2Nb-type Laves phase. Through Nb addition, NiAl-Cr（Mo）/Nb alloy exhibits a reasonable balance of high temperature strength and room temperature compression ductility and its mechanical behaviors are superior to the NiAl-28Cr-6Mo eutectic alloy at all temperature. The elevated temperature compression deformation behavior of NiAl-Cr（Mo）/Nb alloy can be properly described by power-law equation.the National High Technology Committee of China （No. 863-715-005-0030） for financial supports.展开更多
AIM： To evaluate whether the cellular proliferation rate in the large bowel epithelial cells is characterized by circadian rhythm. METHODS： Between January 2003 and December 2004, twenty patients who were diagnosed ...AIM： To evaluate whether the cellular proliferation rate in the large bowel epithelial cells is characterized by circadian rhythm. METHODS： Between January 2003 and December 2004, twenty patients who were diagnosed as suffering from primary, resectable, non-metastatic adenocarcinoma of the lower rectum, infiltrating the sphincter mechanism, underwent abdominoperineal resection, total mesorectal excision and permanent left iliac colostomy. In formalinfixed and paraffin-embedded biopsy specimens obtained from the colostomy mucosa every six hours （00：00, 06：00, 12：00, 18：00 and 24：00）, we studied the expression of G1 phase cyclins （D1 and E） as well as the expression of the G1 phase cyclin-dependent kinase （CDK） inhibitors p16 and p21 as indicators of cell cycle progres- sion in colonic epithelial cells using immunohistochemical methods. RESULTS： The expression of both cyclins showed a similar circadian fashion obtaining their lowest and highest values at 00：00 and 18：00, respectively （P〈 0.001）. A circadian rhythm in the expression of CDK inhibitor proteins p16 and p21 was also observed, with the lowest levels obtained at 12：00 and 18：00 （P〈0.001）, respectively. When the complexes cyclins D1-p21 and E-p21 were examined, the expression of the cyclins was adversely correlated to the p21 expression throughout the day. When the complexes the cyclins D1-p16 and E-p16 were examined, high levels of p16 expression were correlated to low levels of cyclin expression at 00：00, 06：00 and 24：00. Meanwhile, the highest expression levels of both cyclins were correlated to high levels of p16 expression at 18：00. CONCLUSION： Colonic epithelial cells seem to enter the G1 phase of the cell cycle during afternoon （between 12：00 and 18：00） with the highest rates obtained at 18：00. From a clinical point of view, the present results suggest that G1-phase specific anticancer therapies in afternoon might maximize their anti-tumor effect while minimizing toxicity.展开更多
Alloying elements, present in the aluminum solid solution or the precipitates, influence the corrosion resistance of A1-Mg-Mn-Zn alloys. In this study, sensi- tizing treatment was applied to an A1-Mg-Mn-Zn alloy to mo...Alloying elements, present in the aluminum solid solution or the precipitates, influence the corrosion resistance of A1-Mg-Mn-Zn alloys. In this study, sensi- tizing treatment was applied to an A1-Mg-Mn-Zn alloy to modify the precipitation at the grain boundaries or in the grains. Transmission electron microscopy （TEM） and scanning electron microscope （SEM） were used to characterize various second-phase particles and determine their orientation relationship with the A1 matrix. After sensitizing treatment, z-phase （Mg32（Al, Zn）49） is observed to precipitate along the grain boundaries in a coarser size, producing a discontinuous grain boundary precipitate structure. In addition, Mn-rich particles are found to form with various shapes, such as global, plate and rhombus.展开更多
In view of the M_(n+1)AX_(n)(MAX)phase coatings benefting the adaptive passivation flm for good corrosion resistance and high electronic density of states for excellent electrical conductivity,here,we reported the Cr_...In view of the M_(n+1)AX_(n)(MAX)phase coatings benefting the adaptive passivation flm for good corrosion resistance and high electronic density of states for excellent electrical conductivity,here,we reported the Cr_(2)Al C MAX phase coatings with different preferred orientations by a homemade technique consisting of vacuum arc and magnetron sputtering.The dependence of surface and interface microstructural evolution upon the corrosion and electrochemical properties of deposited coating was focused.Results showed that all the Cr_(2)Al C coatings with different phase orientations greatly improved the performance of stainless steel(SS)316 L substrate.Specifcally,the lowest value of interface contact resistance(ICR)reached to 3.16 mΩcm^(2)and the lowest corrosion current density was 2×10^(-2)μA cm^(-2),which were much better than those of bare SS316L.The combined studies of electrochemical properties and theoretical calculations demonstrated that the Cr_(2)Al C coatings with preferred(103)orientation were easier to form oxide passivation flm on their surface to increase the corrosion resistance.展开更多
Short-chain fatty acids(SCFAs)butyrate promote the postnatal rumen epithelial development and maturation in ruminants.However,molecular mechanisms of effects of butyrate on the bovine rumen epithelial cells(BRECs)prol...Short-chain fatty acids(SCFAs)butyrate promote the postnatal rumen epithelial development and maturation in ruminants.However,molecular mechanisms of effects of butyrate on the bovine rumen epithelial cells(BRECs)proliferation remain elusive.Therefore,purpose of this study was to investigate the effects of butyrate on the expression of genes and proteins at G0/G1 and S phase of BRECs cycle.Our results showed that BRECs treated with butyrate inhibited(P<0.05)the proliferation of BRECs,relatively to control.Flow cytometric assays revealed that butyrate triggers the BRECs cycle arrest at the G0/G1 phase.qRT-PCR analyses of mRNA level of genes involved in the G0/G1 phase of cell cycle showed that butyrate significantly upregulated(P<0.001)the expression of mRNA encoding p21^(Cip1)compared with control group,but it decreased(P<0.05)the mRNA levels of cyclin D1 and CDK4 genes at G0/G1 phase checkpoint compared with control.Moreover,Western blot also revealed that butyrate downregulated the expression of cyclin D3,CDK6,p-Rb,and E2F1 proteins involved in the modulation of G0/G1 phase of cell cycle.In conclusion,our results demonstrated that butyrate inhibits the proliferation of BRECs via downregulation of positive regulators at G0/G1 phase checkpoint.展开更多
The main methods of the second phase quantitative analysis in current material science researches are manual recognition and extracting by using software such as Image Tool and Nano Measurer. The weaknesses such as hi...The main methods of the second phase quantitative analysis in current material science researches are manual recognition and extracting by using software such as Image Tool and Nano Measurer. The weaknesses such as high labor intensity and low accuracy statistic results exist in these methods. In order to overcome the shortcomings of the current methods, the Ω phase in A1-Cu-Mg-Ag alloy is taken as the research object and an algorithm based on the digital image processing and pattern recognition is proposed and implemented to do the A1 alloy TEM （transmission electron microscope） digital images process and recognize and extract the information of the second phase in the result image automatically. The top-hat transformation of the mathematical morphology, as well as several imaging processing technologies has been used in the proposed algorithm. Thereinto, top-hat transformation is used for elimination of asymmetric illumination and doing Multi-layer filtering to segment Ω phase in the TEM image. The testing results are satisfied, which indicate that the Ω phase with unclear boundary or small size can be recognized by using this method. The omission of these two kinds of Ω phase can be avoided or significantly reduced. More Ω phases would be recognized （growing rate minimum to 2% and maximum to 400% in samples）, accuracy of recognition and statistics results would be greatly improved by using this method. And the manual error can be eliminated. The procedure recognizing and making quantitative analysis of information in this method is automatically completed by the software. It can process one image, including recognition and quantitative analysis in 30 min, but the manual method such as using Image Tool or Nano Measurer need 2 h or more. The labor intensity is effectively reduced and the working efficiency is greatly improved.展开更多
Metallic few-layered 1T phase vanadium disulfide nanosheets have been employed for boosting sodium ion batteries.It can deliver a capacity of 241 mAh∙g^(−1)at 100 mA∙g^(−1)after 200 cycles.Such long-term stability is ...Metallic few-layered 1T phase vanadium disulfide nanosheets have been employed for boosting sodium ion batteries.It can deliver a capacity of 241 mAh∙g^(−1)at 100 mA∙g^(−1)after 200 cycles.Such long-term stability is attributed to the facile ion diffusion and electron transport resulting from the well-designed two-dimensional(2D)electron-electron correlations among V atoms in the 1T phase and optimized in-planar electric transport.Our results highlight the phase engineering into electrode design for energy storage.展开更多
To observe the effects of basic fibroblast growth factor （bFGF） on human adenoid cystic carcinoma ACC-2 cell line proliferation and ERK, cyclin D1/p21^waf/cip1 signaling pathways, human adenoid cystic carcinoma cel...To observe the effects of basic fibroblast growth factor （bFGF） on human adenoid cystic carcinoma ACC-2 cell line proliferation and ERK, cyclin D1/p21^waf/cip1 signaling pathways, human adenoid cystic carcinoma cells （ACC-2） were cultured and the influence of bFGF of different concentrations on cell proliferation was determined by MTT. Protein was detected by immuno-precipitation and ERK activity by using ERK agent kit. p-ERK1/2 and down-stream cyclin D1, p21^waf/cip1 expression were detected by Western blotting and the interfering role of mitogen protein-activated kinase （MEK） suppressor U0126 in the afore-mentioned indicators was examined. MTT demonstrated ACC-2 cell proliferation was substantially enhanced by bFGF, immuo-precipitation displayed ERK activity was up-regulated by bFGF, and immuno-imprinting also showed p-ERK1/2, cyclin D1 expression was greatly enhanced and p21^waf/cip1 expression was inhibited by bFGE U0126 suppressed the effect of bFGF. It is concluded that bFGF can promote the proliferation of human adenoid cystic carcinoma ACC-2 cells, and its pathways are associated with the up-regulated activity and expression of p-ERK1/2, inhibited p21waf/cip1 expression and enhanced cyclin D1 expression.展开更多
A hybrid approach combining machine learning and microstructure analysis was proposed to investigate the relationship between microstructure and hardness of AA2099 Al−Li alloy through nano-indentation,X-ray diffractio...A hybrid approach combining machine learning and microstructure analysis was proposed to investigate the relationship between microstructure and hardness of AA2099 Al−Li alloy through nano-indentation,X-ray diffraction(XRD)and electron backscatter diffraction(EBSD)technologies.Random forest regression(RFR)model was employed to predict hardness based on microstructural features and uncover influential factors and their rankings.The results show that the increased hardness correlates with a smaller distance from indentation to grain boundary(D_(dis))or a shorter minimum grain axis(D_(min)),a lower Schmidt factor in friction stir weld direction(SF_(FD)),and higher sine values of the angle between{111}slip plane and surface(sinθ_(min)).D_(dis) and D_(min) emerge as pivotal determinants in hardness prediction.High-angle grain boundaries imped dislocation slip,thereby increasing hardness.Crystallographic orientation also significantly influences hardness,especially in the presence of T_(1) phases along{111}Al habit planes.This effect is attributable to the variation in encountered T_(1) variants during indenter loading.Consequently,the importance ranking of microstructural features shifts depending on T_(1) phase abundance:in samples with limited T_(1) phases,D_(dis) or D_(min)>SF_(FD)>sinθ_(min),while in samples with abundant T_(1) phases,D_(dis) or D_(min)>sinθ_(min)>SF_(FD).展开更多
基金supported by the Natural Science Foundation of Beijing City(No.J230034)the Fundamental Research Funds for the Central Universities(No.2023-JYB-JBQN-051)the Talent Cultivation Project of Beijing University of Chinese Medicine(No.JZPY202206).
文摘Gastric cancer(GC)is characterized by high morbidity and mortality rates.Chinese agarwood comprises the resin-containing wood of Aquilaria sinensis(Lour.)Gilg.,traditionally utilized for treating asthma,cardiac ischemia,and tumors.However,comprehensive research regarding its anti-GC effects and underlying mechanisms remains limited.In this study,Chinese agarwood petroleum ether extract(CAPEE)demonstrated potent cytotoxicity against human GC cells,with half maximal inhibitory concentration(IC_(50))values for AGS,HGC27,and MGC803 cells of 2.89,2.46,and 2.37μg·mL^(−1),respectively,at 48 h.CAPEE significantly induced apoptosis in these GC cells,with B-cell lymphoma-2(BCL-2)associated X protein(BAX)/BCL-2 antagonist killer 1(BAK)likely mediating CAPEE-induced apoptosis.Furthermore,CAPEE induced G_(0)/G_(1)phase cell cycle arrest in human GC cells via activation of the deoxyribonucleic acid(DNA)damage-p21-cyclin D1/cyclin-dependent kinase 4(CDK4)signaling axis,and increased Fe^(2+),lipid peroxides and reactive oxygen species(ROS)levels,thereby inducing ferroptosis.Ribonucleic acid(RNA)sequencing,real-time quantitative polymerase chain reaction(RT-qPCR),and Western blotting analyses revealed CAPEE-mediated upregulation of heme oxygenase-1(HO-1)in human GC cells.RNA interference studies demonstrated that HO-1 knockdown reduced CAPEE sensitivity and inhibited CAPEE-induced ferroptosis in human GC cells.Additionally,CAPEE administration exhibited robust in vivo anti-GC activity without significant toxicity in nude mice while inhibiting tumor cell growth and promoting apoptosis in tumor tissues.These findings indicate that CAPEE suppresses human GC cell growth through upregulation of the DNA damage-p21-cyclin D1/CDK4 signaling axis and HO-1-mediated ferroptosis,suggesting its potential as a candidate drug for GC treatment.
基金Project(51176050)supported by the National Natural Science Foundation of ChinaProject(12ZB073)supported by the Research Projects in Sichuan Province Education Office,China
文摘The effect of Ce, Co, and B on the formation of 1：13 phase in La（Fe, Si）13 alloys was investigated by XRD, SEM and EDS. The results show that Co can improve the formation of 1：13 phase in as-cast LaFe11.6-xCoxSi1.4 alloys, but in as-cast and annealed LaFe11.6Si1.4-xCox alloys, it will hamper the formation of 1：13 phase and help the formation of a-Fe（Co, Si） solid solution. Ce2Fel7 phases will form when x reaches a certain value in as-cast and annealed La1-xCexFe11.5Si1.5 alloys. B can improve the formation of 1：13 phase accompanied with Fe2B phase in as-cast LaFe11.6-xBxSi1.4 alloys. B improves the formation of a-Fe solid solution in LaFe11.6Si1.4-xBx alloys, and there is almost only a-Fe in as-cast and annealed LaFe11.6Si0.9B0.5 alloy. In all, the introduction of Co, B, and Ce cannot eliminate the a-Fe phases in corresponding alloys prepared by the high-temperature and short-time annealing process.
基金This work was financially supported by the National High-Tech Research and Development Program of China (No.2006AA03Z523).
文摘The effects of aging on the microstructure, mechanical properties, intergranular corrosion, and exfoliation corrosion of an Al-3.5Cu-1.5Li-0.22（Sc ＋ Zr） alloy have been investigated. The results show that the alloy has the character of age hardening, and the major phase of precipitation and strengthening is the T1 phase. The aging temperature and aging time have a significant effect on the amount and distribution of the T1 phase. The proper artificial single-aging treatment of the alloy is at 160℃ for 40 h. The intergranular corrosion and exfoliation corrosion of the alloy are caused by the anodic dissolution of the T1 phase and the precipitate-free zone （PFZ）. With increasing the aging time to overaged, the T1 phase coarsens, and the PFZ widens, leading to an increase in the susceptibility to intergranular corrosion and exfoliation corrosion.
基金supported by the 100 Talents Program of the Chinese Academy of Sciences, National Natural Science Foundation of China (Nos. 21173226, 21376247)State Key Laboratory of Multiphase Complex Systems, Institute of Process Engineering, Chinese Academy of Sciences (Nos. MPCS-2011-D-08, MPCS-2010-C-02)
文摘A 1-dodecanethiol-based phase-transfer protocol is developed for the extraction of noble metal ions from aqueous solution to a hydrocarbon phase, which calls for first mixing the aqueous metal ion solution with an ethanolic solution of 1-dodecanethiol, and then extracting the coordination compounds formed between noble metal ions and 1-dodecanethiol into a non-polar organic solvent. A number of characterization techniques, including inductively coupled plasma atomic emission spectroscopy, Fourier transform infrared spectroscopy, and thermogravimetric analysis demonstrate that this protocol could be applied to extract a wide variety of noble metal ions from water to dichlorometh- ane with an efficiency of 〉96%, and has high selectivity for the separation of the noble metal ions from other transition metals. It is therefore an attractive alternative for the extraction of noble metals from water, soil, or waste printed circuit boards.
基金Project（2016YFB0300901） supported by the National Key R＆D Program of China Project（51421001） supported by the National Natural Science Foundation of China Project（2018CDJDCL0019） supported by the Fundamental Research Funds for the Central Universities, China
文摘The precipitation behaviors of an A1-Cu-Li-Mn-Zr alloy at different ageing temperatures （120, 160 and 200 ~C） were investigated using Vickers hardness measurements and transmission electron microscopy （TEM） characterization. Age hardening curves show an increase in precipitation kinetics with increasing ageing temperature. The results of TEM show that for the samples peak aged at 120 ~C, the amount of g＇ （A13Li）, GP zones/0＇ （A12Cu） and Z （A15Cu6Li2） phases is obviously higher than that of T1 （A12CuLi） precipitates; while the samples peak aged at 160 and 200 ~C are usually dominated by T1 phase with a minor fraction of GP zones/0＇ and g＇, and the Z phase almost does not form. In addition, quantitative analysis on the T1 platelets demonstrates that the samples peak aged at 200 ~C have larger plate diameter and smaller area fraction of T1, as compared to the samples peak aged at 160 ~C. Correspondingly, the possible reasons for such phenomena are discussed.
基金supported by the National Natural Science Foundation of China(30970673,81172634)Natural Science Foundation of Guangdong Province(9151022501000013,S2011040003686)+1 种基金Guangdong Province"211Project"(200826GW,201007GW)Grant from School of Public Health and Tropical Medicine of Southern Medical University,China(Grant No.GW201111)
文摘Abstract Objective To examine UVB-induced responses in normal human keratinocytes （HaCaT） and epidermoid carcinoma cells （A431） at the cellular and molecular level, and investigated the protective effect of salidroside. Methods Cells irradiated by UVB at various dosage and their viability was assessed by MTT assays, cell cycle was analysed by flow cytometry. The expression of NF-KB, BCL-2, and CDK6 after 50 J/㎡ UVB irradiation were detected by RT-PCR and western blotting. Results Our results confirmed greater tolerance of A341 cells to UVB-induced damage such as cell viability and cell cycle arrest, which was accompanied by differential expression changes in NF-KB, BCL-2, and CDK6. UVB exposure resulted in HaCaT cells undergoing G1-S phase arrest. When treated with salidroside, HaCaT survival was significantly enhanced following exposure to UVB, suggesting great therapeutic potential for this compound. Conclusion Taken together, our study suggests that A431 respond differently to UVB than norma HaCaT cells, and supports a role for NF-KB, CDK6, and BCL-2 in UVB-induced cell G1-S phase arrest Furthermore, salidroside can effectively protect HaCaT from UVB irradiation.
基金Project(21406273)supported by the National Natural Science Foundation of China
文摘Magneli phase titanium sub-oxide conductive ceramic Tin O2n-1 was used as the support for Pt due to its excellent resistance to electrochemical oxidation, and Pt/Tin O2n-1 composites were prepared by the impregnation-reduction method. The electrochemical stability of Tin O2n-1 was investigated and the results show almost no change in the redox region after oxidation for 20 h at 1.2 V(vs NHE) in 0.5 mol/L H2SO4 aqueous solution. The catalytic activity and stability of the Pt/Tin O2n-1 toward the oxygen reduction reaction(ORR) in 0.5 mol/L H2SO4 solution were investigated through the accelerated aging tests(AAT), and the morphology of the catalysts before and after the AAT was observed by transmission electron microscopy. At the potential of 0.55 V(vs SCE), the specific kinetic current density of the ORR on the Pt/Tin O2n-1 is about 1.5 times that of the Pt/C. The LSV curves for the Pt/C shift negatively obviously with the half-wave potential shifting about 0.02 V after 8000 cycles AAT, while no obvious change takes place for the LSV curves for the Pt/Tin O2n-1. The Pt particles supported on the carbon aggregate obviously, while the morphology of the Pt supported on Tin O2n-1 remains almost unchanged, which contributes to the electrochemical surface area loss of Pt/C being about 2times that of the Pt/Tin O2n-1. The superior catalytic stability of Pt/Tin O2n-1 toward the ORR could be attributed to the excellent stability of the Tin O2n-1 and the electronic interaction between the metals and the support.
基金supported by National Natural Science Foundation of China(Nos.20975056,21275082 and 81102411)Natural Science Foundation of Shandong(Nos. ZR2011BZ004,ZR2011BQ005)+2 种基金JSPS and NSFC under the Japan-China Scientific Cooperation Program(No.21111140014)State Key Laboratory of Analytical Chemistry for Life Science(No. SKLACLS1110)the National Key Basic Research Development Program of China(973 Special Preliminary Study Plan,No. 2012CB722705)
文摘In this work, a new sample pretreatment method prior to HPLC separations was developed for the determination of auxins in plant samples, Owing to its large surface area and high adsorption capacity, multi-walled carbon nanotube （MWCNT） was chosen as the adsorbent for the extraction of auxins from plant samples. In this study, two important auxins were selected as model analytes, namely indole-3- butyric acid （IBA） and 1-naphthylacetic acid （NAA）. They could be extracted and concentrated due to their π-π stacking interactions with MWCNT. Then HPLC-UV was introduced to detect IBA and NAA after sample pretreatment. Factors that may affect the enrichment efficiency were investigated and optimized. Comparative studies showed that MWCNT was superior to CI 8 for the extraction of the two analytes. Validation experiments showed that the optimized method had good linearity （0.9998 and 0.9960）, high recovery （81.4%-85.4%）, and low detection limits （0.0030 mg/L and 0.0012 mg/L）. The results indicated that the novel method had advantages of convenience, good sensitivity, high efficiency, and it was feasible for the determination of auxins in plant samples.
基金This work was supported by The National Key Basic Reserch and Development Project of China(2004CB418303)Project 4023100 of the Major Research Program for Global Change and Regional ResponseNational Natural Science Foundation of China(Grant No.40231005).
文摘The mechanism of the locking of the E1 Nino event onset phase to boreal spring （from April to June） in an intermediate coupled ocean-atmosphere model is investigated. The results show that the seasonal variation of the zonal wind anomaly over the equatorial Pacific associated with the seasonal variation of the ITCZ is the mechanism of the locking in the model. From January to March of the E1 Nino year, the western wind anomaly over the western equatorial Pacific can excite the downwelling Kelvin wave that propagates eastward to the eastern and middle Pacific by April to June. From April to December of the year before the E1 Nifio year, the eastern wind anomaly over the equatorial Pacific forces the downwelling Rossby waves that modulate the ENSO cycle. The modulation and the reflection at the western boundary modulate the time of the transition from the cool to the warm phase to September of the year before the E1 Nifio year and cause the strongest downwelling Kelvin wave from the reflected Rossby waves at the western boundary to arrive in the middle and eastern equatorial Pacific by April to June of the E1 Nino year. The superposition of these two kinds of downwelling Kelvin waves causes the El Nino event to tend to occur from April to June.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11474095,11654005,and 11234003)the National Key Research and Development Program of China(Grant No.2016YFA0302000)
文摘We theoretically study the quantum Fisher information（QFI） of the SU（1,1） interferometer with phase shifts in two arms by coherent squeezed vacuum state input, and give the comparison with the result of phase shift only in one arm.Different from the traditional Mach–Zehnder interferometer, the QFI of single-arm case for an SU（1,1） interferometer can be slightly higher or lower than that of two-arm case, which depends on the intensities of the two arms of the interferometer.For coherent squeezed vacuum state input with a fixed mean photon number, the optimal sensitivity is achieved with a squeezed vacuum input in one mode and the vacuum input in the other.
基金The authors would like to acknowledge the National Natural Science Foundation of China(No.59895152)the National High Technology Committee of China(No.863-715-005-0030)for financial supports.
文摘The microstructure and mechanical behaviors of NiAl-28Cr-5Mo-1Nb eutectic alloy were investigated by using scanning electron microscopy, X-ray diffraction, transmission electron microscopy and compression tests, respectively. The alloy is mainly composed of three phases, which are the gray lamellar Cr（Mo） plate, black NiAI matrix and semicontinuously distributed Cr2Nb-type Laves phase. Through Nb addition, NiAl-Cr（Mo）/Nb alloy exhibits a reasonable balance of high temperature strength and room temperature compression ductility and its mechanical behaviors are superior to the NiAl-28Cr-6Mo eutectic alloy at all temperature. The elevated temperature compression deformation behavior of NiAl-Cr（Mo）/Nb alloy can be properly described by power-law equation.the National High Technology Committee of China （No. 863-715-005-0030） for financial supports.
文摘AIM： To evaluate whether the cellular proliferation rate in the large bowel epithelial cells is characterized by circadian rhythm. METHODS： Between January 2003 and December 2004, twenty patients who were diagnosed as suffering from primary, resectable, non-metastatic adenocarcinoma of the lower rectum, infiltrating the sphincter mechanism, underwent abdominoperineal resection, total mesorectal excision and permanent left iliac colostomy. In formalinfixed and paraffin-embedded biopsy specimens obtained from the colostomy mucosa every six hours （00：00, 06：00, 12：00, 18：00 and 24：00）, we studied the expression of G1 phase cyclins （D1 and E） as well as the expression of the G1 phase cyclin-dependent kinase （CDK） inhibitors p16 and p21 as indicators of cell cycle progres- sion in colonic epithelial cells using immunohistochemical methods. RESULTS： The expression of both cyclins showed a similar circadian fashion obtaining their lowest and highest values at 00：00 and 18：00, respectively （P〈 0.001）. A circadian rhythm in the expression of CDK inhibitor proteins p16 and p21 was also observed, with the lowest levels obtained at 12：00 and 18：00 （P〈0.001）, respectively. When the complexes cyclins D1-p21 and E-p21 were examined, the expression of the cyclins was adversely correlated to the p21 expression throughout the day. When the complexes the cyclins D1-p16 and E-p16 were examined, high levels of p16 expression were correlated to low levels of cyclin expression at 00：00, 06：00 and 24：00. Meanwhile, the highest expression levels of both cyclins were correlated to high levels of p16 expression at 18：00. CONCLUSION： Colonic epithelial cells seem to enter the G1 phase of the cell cycle during afternoon （between 12：00 and 18：00） with the highest rates obtained at 18：00. From a clinical point of view, the present results suggest that G1-phase specific anticancer therapies in afternoon might maximize their anti-tumor effect while minimizing toxicity.
基金financially supported by the National Natural Science Foundation of China (No.51301017)the Common Construction Project from Beijing Municipal Commission of Education
文摘Alloying elements, present in the aluminum solid solution or the precipitates, influence the corrosion resistance of A1-Mg-Mn-Zn alloys. In this study, sensi- tizing treatment was applied to an A1-Mg-Mn-Zn alloy to modify the precipitation at the grain boundaries or in the grains. Transmission electron microscopy （TEM） and scanning electron microscope （SEM） were used to characterize various second-phase particles and determine their orientation relationship with the A1 matrix. After sensitizing treatment, z-phase （Mg32（Al, Zn）49） is observed to precipitate along the grain boundaries in a coarser size, producing a discontinuous grain boundary precipitate structure. In addition, Mn-rich particles are found to form with various shapes, such as global, plate and rhombus.
基金fnancially supported by the National Science Found for Distinguished Young Scholars of China(No.52025014)the National Science and Technology Major Project(No.2017VII-0012–0108)+1 种基金the National Science Foundation of China(Nos.51901238 and 52101109)the Natural Science Foundation of Ningbo(Nos.202003N4350 and 202003N4025)。
文摘In view of the M_(n+1)AX_(n)(MAX)phase coatings benefting the adaptive passivation flm for good corrosion resistance and high electronic density of states for excellent electrical conductivity,here,we reported the Cr_(2)Al C MAX phase coatings with different preferred orientations by a homemade technique consisting of vacuum arc and magnetron sputtering.The dependence of surface and interface microstructural evolution upon the corrosion and electrochemical properties of deposited coating was focused.Results showed that all the Cr_(2)Al C coatings with different phase orientations greatly improved the performance of stainless steel(SS)316 L substrate.Specifcally,the lowest value of interface contact resistance(ICR)reached to 3.16 mΩcm^(2)and the lowest corrosion current density was 2×10^(-2)μA cm^(-2),which were much better than those of bare SS316L.The combined studies of electrochemical properties and theoretical calculations demonstrated that the Cr_(2)Al C coatings with preferred(103)orientation were easier to form oxide passivation flm on their surface to increase the corrosion resistance.
基金This study was supported by the National Natural Science Foundation of China(No.32002200)the Research Project of Natural Science Foundation of Jiangsu Province(BK20190898)China Agriculture Research System of MOF and MARA.
文摘Short-chain fatty acids(SCFAs)butyrate promote the postnatal rumen epithelial development and maturation in ruminants.However,molecular mechanisms of effects of butyrate on the bovine rumen epithelial cells(BRECs)proliferation remain elusive.Therefore,purpose of this study was to investigate the effects of butyrate on the expression of genes and proteins at G0/G1 and S phase of BRECs cycle.Our results showed that BRECs treated with butyrate inhibited(P<0.05)the proliferation of BRECs,relatively to control.Flow cytometric assays revealed that butyrate triggers the BRECs cycle arrest at the G0/G1 phase.qRT-PCR analyses of mRNA level of genes involved in the G0/G1 phase of cell cycle showed that butyrate significantly upregulated(P<0.001)the expression of mRNA encoding p21^(Cip1)compared with control group,but it decreased(P<0.05)the mRNA levels of cyclin D1 and CDK4 genes at G0/G1 phase checkpoint compared with control.Moreover,Western blot also revealed that butyrate downregulated the expression of cyclin D3,CDK6,p-Rb,and E2F1 proteins involved in the modulation of G0/G1 phase of cell cycle.In conclusion,our results demonstrated that butyrate inhibits the proliferation of BRECs via downregulation of positive regulators at G0/G1 phase checkpoint.
基金Project(51171209)supported by the National Natural Science Foundation of China
文摘The main methods of the second phase quantitative analysis in current material science researches are manual recognition and extracting by using software such as Image Tool and Nano Measurer. The weaknesses such as high labor intensity and low accuracy statistic results exist in these methods. In order to overcome the shortcomings of the current methods, the Ω phase in A1-Cu-Mg-Ag alloy is taken as the research object and an algorithm based on the digital image processing and pattern recognition is proposed and implemented to do the A1 alloy TEM （transmission electron microscope） digital images process and recognize and extract the information of the second phase in the result image automatically. The top-hat transformation of the mathematical morphology, as well as several imaging processing technologies has been used in the proposed algorithm. Thereinto, top-hat transformation is used for elimination of asymmetric illumination and doing Multi-layer filtering to segment Ω phase in the TEM image. The testing results are satisfied, which indicate that the Ω phase with unclear boundary or small size can be recognized by using this method. The omission of these two kinds of Ω phase can be avoided or significantly reduced. More Ω phases would be recognized （growing rate minimum to 2% and maximum to 400% in samples）, accuracy of recognition and statistics results would be greatly improved by using this method. And the manual error can be eliminated. The procedure recognizing and making quantitative analysis of information in this method is automatically completed by the software. It can process one image, including recognition and quantitative analysis in 30 min, but the manual method such as using Image Tool or Nano Measurer need 2 h or more. The labor intensity is effectively reduced and the working efficiency is greatly improved.
基金the National Natural Science Foundation of China(52002366,22075263)the Fundamental Research Funds for the Central Universities(WK2060000039)+1 种基金the Natural Science Foundation of Higher Education Institutions of the Anhui Province(KJ2021A0132)the Key Research and Development Program of the Anhui Province(202104a05020070)for financial support.We are thankful for support from the USTC center for micro-and nanoscale research and fabrication,supercomputing system in the supercomputing center of the USTC.
文摘Metallic few-layered 1T phase vanadium disulfide nanosheets have been employed for boosting sodium ion batteries.It can deliver a capacity of 241 mAh∙g^(−1)at 100 mA∙g^(−1)after 200 cycles.Such long-term stability is attributed to the facile ion diffusion and electron transport resulting from the well-designed two-dimensional(2D)electron-electron correlations among V atoms in the 1T phase and optimized in-planar electric transport.Our results highlight the phase engineering into electrode design for energy storage.
文摘To observe the effects of basic fibroblast growth factor （bFGF） on human adenoid cystic carcinoma ACC-2 cell line proliferation and ERK, cyclin D1/p21^waf/cip1 signaling pathways, human adenoid cystic carcinoma cells （ACC-2） were cultured and the influence of bFGF of different concentrations on cell proliferation was determined by MTT. Protein was detected by immuno-precipitation and ERK activity by using ERK agent kit. p-ERK1/2 and down-stream cyclin D1, p21^waf/cip1 expression were detected by Western blotting and the interfering role of mitogen protein-activated kinase （MEK） suppressor U0126 in the afore-mentioned indicators was examined. MTT demonstrated ACC-2 cell proliferation was substantially enhanced by bFGF, immuo-precipitation displayed ERK activity was up-regulated by bFGF, and immuno-imprinting also showed p-ERK1/2, cyclin D1 expression was greatly enhanced and p21^waf/cip1 expression was inhibited by bFGE U0126 suppressed the effect of bFGF. It is concluded that bFGF can promote the proliferation of human adenoid cystic carcinoma ACC-2 cells, and its pathways are associated with the up-regulated activity and expression of p-ERK1/2, inhibited p21waf/cip1 expression and enhanced cyclin D1 expression.
基金financially supported by the National Natural Science Foundation of China (No.51871038)the Natural Science Foundation of Chongqing,China (Nos.CSTB2022NSCQ-LZX0002,cstc2021jcyjmsxm X0960)。
文摘A hybrid approach combining machine learning and microstructure analysis was proposed to investigate the relationship between microstructure and hardness of AA2099 Al−Li alloy through nano-indentation,X-ray diffraction(XRD)and electron backscatter diffraction(EBSD)technologies.Random forest regression(RFR)model was employed to predict hardness based on microstructural features and uncover influential factors and their rankings.The results show that the increased hardness correlates with a smaller distance from indentation to grain boundary(D_(dis))or a shorter minimum grain axis(D_(min)),a lower Schmidt factor in friction stir weld direction(SF_(FD)),and higher sine values of the angle between{111}slip plane and surface(sinθ_(min)).D_(dis) and D_(min) emerge as pivotal determinants in hardness prediction.High-angle grain boundaries imped dislocation slip,thereby increasing hardness.Crystallographic orientation also significantly influences hardness,especially in the presence of T_(1) phases along{111}Al habit planes.This effect is attributable to the variation in encountered T_(1) variants during indenter loading.Consequently,the importance ranking of microstructural features shifts depending on T_(1) phase abundance:in samples with limited T_(1) phases,D_(dis) or D_(min)>SF_(FD)>sinθ_(min),while in samples with abundant T_(1) phases,D_(dis) or D_(min)>sinθ_(min)>SF_(FD).
