The significant effect of MgO in inhibiting the reduction swelling of iron ore pellets has been widely recognized.The swelling behaviors of pellets during the stepwise reduction by CO were assessed.The linear expansio...The significant effect of MgO in inhibiting the reduction swelling of iron ore pellets has been widely recognized.The swelling behaviors of pellets during the stepwise reduction by CO were assessed.The linear expansion of strip samples was measured using a linear dilatometer during the staged reduction process at a temperature of 900℃.The existence states of MgO in hematite,magnetite,and wüstite were investigated through thermodynamic calculations.The magnetite strip samples were subjected to oxidizing roasting at 1250℃ for 30 min to produce hematite strip samples.The strip samples with 0.49,1.49,2.49,and 3.49 wt.%MgO were analyzed for length change.It was observed that the sample with 2.49 wt.%MgO exhibited the least significant length change.The lengths of the samples with the initial length being 20 mm before reduction changed during the reduction stages of Fe_(2)O_(3)→Fe_(3)O_(4),Fe_(3)O_(4)→FeO,and FeO→Fe were 615,−25,and−378μm,respectively.The volume expansion of hematite to magnetite was primarily attributed to the crystal transformation.During the reduction stage from wüstite to metallic iron,a substantial contraction occurred,while the slag phase was able to retain its original basic shape.The enclosed areas,as indicated by the expansion change curves of the samples with 0.49,1.49,2.49,and 3.49 wt.%MgO,were measured at 3.76×10^(6),3.23×10^(6),3.05×10^(6),and 3.17×10^(6)μm s,respectively.展开更多
BACKGROUND Hepatitis B(HB)and hepatitis C(HC)place the largest burden in China,and a goal of eliminating them as a major public health threat by 2030 has been set.Making more informed and accurate forecasts of their s...BACKGROUND Hepatitis B(HB)and hepatitis C(HC)place the largest burden in China,and a goal of eliminating them as a major public health threat by 2030 has been set.Making more informed and accurate forecasts of their spread is essential for developing effective strategies,heightening the requirement for early warning to deal with such a major public health threat.AIM To monitor HB and HC epidemics by the design of a paradigmatic seasonal autoregressive fractionally integrated moving average(SARFIMA)for projections into 2030,and to compare the effectiveness with the seasonal autoregressive integrated moving average(SARIMA).METHODS Monthly HB and HC incidence cases in China were obtained from January 2004 to June 2023.Descriptive analysis and the Hodrick-Prescott method were employed to identify trends and seasonality.Two periods(from January 2004 to June 2022 and from January 2004 to December 2015,respectively)were used as the training sets to develop both models,while the remaining periods served as the test sets to evaluate the forecasting accuracy.RESULTS There were incidents of 23400874 HB cases and 3590867 HC cases from January 2004 to June 2023.Overall,HB remained steady[average annual percentage change(AAPC)=0.44,95%confidence interval(95%CI):-0.94-1.84]while HC was increasing(AAPC=8.91,95%CI:6.98-10.88),and both had a peak in March and a trough in February.In the 12-step-ahead HB forecast,the mean absolute deviation(15211.94),root mean square error(18762.94),mean absolute percentage error(0.17),mean error rate(0.15),and root mean square percentage error(0.25)under the best SARFIMA(3,0,0)(0,0.449,2)12 were smaller than those under the best SARIMA(3,0,0)(0,1,2)12(16867.71,20775.12,0.19,0.17,and 0.27,respectively).Similar results were also observed for the 90-step-ahead HB,12-step-ahead HC,and 90-step-ahead HC forecasts.The predicted HB incidents totaled 9865400(95%CI:7508093-12222709)cases and HC totaled 1659485(95%CI:856681-2462290)cases during 2023-2030.CONCLUSION Under current interventions,China faces enormous challenges to eliminate HB and HC epidemics by 2030,and effective strategies must be reinforced.The integration of SARFIMA into public health for the management of HB and HC epidemics can potentially result in more informed and efficient interventions,surpassing the capabilities of SARIMA.展开更多
Regular TiN is harmful to the toughness of steel,and its shape and size need to be controlled.Understanding the behavior of TiN precipitation on CeAlO_(3) surfaces is critical for controlling the morphology and format...Regular TiN is harmful to the toughness of steel,and its shape and size need to be controlled.Understanding the behavior of TiN precipitation on CeAlO_(3) surfaces is critical for controlling the morphology and formation process of CeAlO_(3)–TiN composite inclusions in the steel.Experimental results showed that TiN had a square morphology on the CeAlO3 surface,and electron backscatter diffraction phase identification results revealed the orientation relationship between CeAlO_(3) and TiN as follows:(001)_(CeAlO_(3))//(110)_(TiN),(100)_(CeAlO_(3))/(001)_(TiN),and[010]_(CeAlO_(3))/[110]_(TiN).The CeAlO3 crystal structure was studied using the first-principles calculation method,and the adsorption and growth process of TiN on the CeAlO_(3) surface were investigated from the atomic scale.The calculation results indicate that there is no metallic bonding present in the CeAlO_(3) system.Among the low-index crystal planes of CeAlO_(3),the(110)planes terminated with O and CeAlO have the highest and lowest surface energies,respectively,with values of 0.373 and 0.051 eV/Å^(2).On the high surface energy plane of CeAlO_(3),the TiN atomic permutation structure is consistent with the arrangement of Ti and N atoms in TiN(100)or(110).For the low surface energy plane of CeAlO_(3),the Ti and N atoms are arranged in a ring-like structure.展开更多
Nitrenes,as neutral monovalent nitrogen-centered molecular species,can insert into various bond or remove nitrogen atoms from amines.Nitrene assisted single-atom skeletal editing,discovered decades ago,provides an eff...Nitrenes,as neutral monovalent nitrogen-centered molecular species,can insert into various bond or remove nitrogen atoms from amines.Nitrene assisted single-atom skeletal editing,discovered decades ago,provides an efficient approach for the precise alteration of cyclic skeletons.In this review,we briefly summarize early studies on skeletal editing of cyclic frameworks involving nitrene species,and introduce several recent important advances systematically.展开更多
Objective:Although there have been improvements in targeted therapy and immunotherapy,the majority of lung adenocarcinoma(LUAD)patients still lack effective therapies.Consequently,it is urgent to screen for new diagno...Objective:Although there have been improvements in targeted therapy and immunotherapy,the majority of lung adenocarcinoma(LUAD)patients still lack effective therapies.Consequently,it is urgent to screen for new diagnosis biomarkers and pharmacological targets.Junctional adhesion molecule-like protein(JAML)was considered to be an oncogenic protein and may be a novel therapeutic target in LUAD.Kaempferol is a natural flavonoid that exhibits antitumor activities in LUAD.However,the effect of kaempferol on JAML is still unknown.Methods:Small interfering RNA was used to knockdown JAML expression.The cell viability was determined using the cell counting kit-8 assay.The proliferation of LUAD cells was evaluated using the 5-ethynyl-2'-deoxyuridine incorporation assay.The migration and invasion of LUAD cells were evaluated by transwell assays.Molecular mechanisms were explored by Western blotting.Results:JAML knockdown suppressed proliferation,migration and invasion of LUAD cells,and JAML deficiency restrained epithelial-mesenchymal transition(EMT)via inactivating the phosphoinositide 3-kinase/protein kinase B/mammalian target of rapamycin(PI3K/AKT/mTOR)pathway.Using a PI3K activator(740Y-P),rescue experiments showed that phenotypes to JAML knockdown in LUAD cells were dependent on the PI3K/AKT/mTOR pathway.Kaempferol also inhibited proliferation,migration and invasion of A549 and H1299 cells and partially suppressed EMT through the PI3K/AKT/mTOR pathway.Knockdown of JAML ameliorated the inhibitory effect of kaempferol on LUAD cells.Kaempferol exerted anticancer effects by targeting JAML.Conclusion:JAML is a novel target for kaempferol against LUAD cells.展开更多
By capitalizing on the capability of photoredox catalysis to generate reactive radical intermediate under mild conditions, we established a photocatalytic cross-coupling protocol that could deliver both derivatives fr...By capitalizing on the capability of photoredox catalysis to generate reactive radical intermediate under mild conditions, we established a photocatalytic cross-coupling protocol that could deliver both derivatives from 1-bromo-2-naphthols in combination with 2-naphthols or 2-naphthylamines. This distinct activation mode could overcome structural or electronic limitation associated with conventional coupling pathways. Additionally, a novel kinetic resolution protocol of unprotected BINOLs has been established with azodicarboxylates via chiral phosphoric acid(CPA) catalysis. Selectivity factor of up to 175 could be achieved and delivered to both enantiomers in atropisomerically enriched form after a simple work-up.展开更多
基金support from the 2023 Basic Research Foundation Project for Universities in the Inner Mongolia Autonomous Region(Grant No.2023RCTD006)the National Natural Science Foundation of China(Grant No.51864041,51664044).
文摘The significant effect of MgO in inhibiting the reduction swelling of iron ore pellets has been widely recognized.The swelling behaviors of pellets during the stepwise reduction by CO were assessed.The linear expansion of strip samples was measured using a linear dilatometer during the staged reduction process at a temperature of 900℃.The existence states of MgO in hematite,magnetite,and wüstite were investigated through thermodynamic calculations.The magnetite strip samples were subjected to oxidizing roasting at 1250℃ for 30 min to produce hematite strip samples.The strip samples with 0.49,1.49,2.49,and 3.49 wt.%MgO were analyzed for length change.It was observed that the sample with 2.49 wt.%MgO exhibited the least significant length change.The lengths of the samples with the initial length being 20 mm before reduction changed during the reduction stages of Fe_(2)O_(3)→Fe_(3)O_(4),Fe_(3)O_(4)→FeO,and FeO→Fe were 615,−25,and−378μm,respectively.The volume expansion of hematite to magnetite was primarily attributed to the crystal transformation.During the reduction stage from wüstite to metallic iron,a substantial contraction occurred,while the slag phase was able to retain its original basic shape.The enclosed areas,as indicated by the expansion change curves of the samples with 0.49,1.49,2.49,and 3.49 wt.%MgO,were measured at 3.76×10^(6),3.23×10^(6),3.05×10^(6),and 3.17×10^(6)μm s,respectively.
基金Supported by the Key Scientific Research Project of Universities in Henan Province,No.21A330004Natural Science Foundation in Henan Province,No.222300420265.
文摘BACKGROUND Hepatitis B(HB)and hepatitis C(HC)place the largest burden in China,and a goal of eliminating them as a major public health threat by 2030 has been set.Making more informed and accurate forecasts of their spread is essential for developing effective strategies,heightening the requirement for early warning to deal with such a major public health threat.AIM To monitor HB and HC epidemics by the design of a paradigmatic seasonal autoregressive fractionally integrated moving average(SARFIMA)for projections into 2030,and to compare the effectiveness with the seasonal autoregressive integrated moving average(SARIMA).METHODS Monthly HB and HC incidence cases in China were obtained from January 2004 to June 2023.Descriptive analysis and the Hodrick-Prescott method were employed to identify trends and seasonality.Two periods(from January 2004 to June 2022 and from January 2004 to December 2015,respectively)were used as the training sets to develop both models,while the remaining periods served as the test sets to evaluate the forecasting accuracy.RESULTS There were incidents of 23400874 HB cases and 3590867 HC cases from January 2004 to June 2023.Overall,HB remained steady[average annual percentage change(AAPC)=0.44,95%confidence interval(95%CI):-0.94-1.84]while HC was increasing(AAPC=8.91,95%CI:6.98-10.88),and both had a peak in March and a trough in February.In the 12-step-ahead HB forecast,the mean absolute deviation(15211.94),root mean square error(18762.94),mean absolute percentage error(0.17),mean error rate(0.15),and root mean square percentage error(0.25)under the best SARFIMA(3,0,0)(0,0.449,2)12 were smaller than those under the best SARIMA(3,0,0)(0,1,2)12(16867.71,20775.12,0.19,0.17,and 0.27,respectively).Similar results were also observed for the 90-step-ahead HB,12-step-ahead HC,and 90-step-ahead HC forecasts.The predicted HB incidents totaled 9865400(95%CI:7508093-12222709)cases and HC totaled 1659485(95%CI:856681-2462290)cases during 2023-2030.CONCLUSION Under current interventions,China faces enormous challenges to eliminate HB and HC epidemics by 2030,and effective strategies must be reinforced.The integration of SARFIMA into public health for the management of HB and HC epidemics can potentially result in more informed and efficient interventions,surpassing the capabilities of SARIMA.
基金financially supported by the National Natural Science Foundation of China(Grant Nos.51874186 and 51864041)the Natural Science Foundation of Inner Mongolia Autonomous Region,China(Grant No.2022MS05017).
文摘Regular TiN is harmful to the toughness of steel,and its shape and size need to be controlled.Understanding the behavior of TiN precipitation on CeAlO_(3) surfaces is critical for controlling the morphology and formation process of CeAlO_(3)–TiN composite inclusions in the steel.Experimental results showed that TiN had a square morphology on the CeAlO3 surface,and electron backscatter diffraction phase identification results revealed the orientation relationship between CeAlO_(3) and TiN as follows:(001)_(CeAlO_(3))//(110)_(TiN),(100)_(CeAlO_(3))/(001)_(TiN),and[010]_(CeAlO_(3))/[110]_(TiN).The CeAlO3 crystal structure was studied using the first-principles calculation method,and the adsorption and growth process of TiN on the CeAlO_(3) surface were investigated from the atomic scale.The calculation results indicate that there is no metallic bonding present in the CeAlO_(3) system.Among the low-index crystal planes of CeAlO_(3),the(110)planes terminated with O and CeAlO have the highest and lowest surface energies,respectively,with values of 0.373 and 0.051 eV/Å^(2).On the high surface energy plane of CeAlO_(3),the TiN atomic permutation structure is consistent with the arrangement of Ti and N atoms in TiN(100)or(110).For the low surface energy plane of CeAlO_(3),the Ti and N atoms are arranged in a ring-like structure.
基金financial support from the National Key R&D Programof China(2022YFA1503703toB.T.and 2021YFF0701604 to B.T.)National Natural Science Foundation of China(22231004 to B.T.,22371113 to Y.-B.W.,22271135 to S.-H.X.)+1 种基金Guangdong Innovative Program(2019BT02Y335 to B.T.)Shenzhen Science and Technology Program(JCYJ20220818100604009 to Y.-B.W.,JCYJ20210324105005015 to S.-H.X.,JCYJ20210324104212035 to Y.-B.W.and KQTD20210811090112004 to B.T.).
文摘Nitrenes,as neutral monovalent nitrogen-centered molecular species,can insert into various bond or remove nitrogen atoms from amines.Nitrene assisted single-atom skeletal editing,discovered decades ago,provides an efficient approach for the precise alteration of cyclic skeletons.In this review,we briefly summarize early studies on skeletal editing of cyclic frameworks involving nitrene species,and introduce several recent important advances systematically.
基金supported by the National Natural Science Foundation of China(Grant No.81973630)National Clinical Key Specialty Project Foundation(Grant No.Z155080000004).
文摘Objective:Although there have been improvements in targeted therapy and immunotherapy,the majority of lung adenocarcinoma(LUAD)patients still lack effective therapies.Consequently,it is urgent to screen for new diagnosis biomarkers and pharmacological targets.Junctional adhesion molecule-like protein(JAML)was considered to be an oncogenic protein and may be a novel therapeutic target in LUAD.Kaempferol is a natural flavonoid that exhibits antitumor activities in LUAD.However,the effect of kaempferol on JAML is still unknown.Methods:Small interfering RNA was used to knockdown JAML expression.The cell viability was determined using the cell counting kit-8 assay.The proliferation of LUAD cells was evaluated using the 5-ethynyl-2'-deoxyuridine incorporation assay.The migration and invasion of LUAD cells were evaluated by transwell assays.Molecular mechanisms were explored by Western blotting.Results:JAML knockdown suppressed proliferation,migration and invasion of LUAD cells,and JAML deficiency restrained epithelial-mesenchymal transition(EMT)via inactivating the phosphoinositide 3-kinase/protein kinase B/mammalian target of rapamycin(PI3K/AKT/mTOR)pathway.Using a PI3K activator(740Y-P),rescue experiments showed that phenotypes to JAML knockdown in LUAD cells were dependent on the PI3K/AKT/mTOR pathway.Kaempferol also inhibited proliferation,migration and invasion of A549 and H1299 cells and partially suppressed EMT through the PI3K/AKT/mTOR pathway.Knockdown of JAML ameliorated the inhibitory effect of kaempferol on LUAD cells.Kaempferol exerted anticancer effects by targeting JAML.Conclusion:JAML is a novel target for kaempferol against LUAD cells.
基金supported by the National Natural Science Foundation of China (21825105)the Guangdong Provincial Key Laboratory of Catalysis (2020B121201002)+3 种基金the Guangdong Innovative Program (2019BT02Y335)the Shenzhen Special Funds (JCYJ20190812-112603598, JCYJ20210324120205016)the Shenzhen Nobel Prize Scientists Laboratory Project (C17213101)the SUSTech Special Fund for the Construction of High-Level Universities (G02216302)。
文摘By capitalizing on the capability of photoredox catalysis to generate reactive radical intermediate under mild conditions, we established a photocatalytic cross-coupling protocol that could deliver both derivatives from 1-bromo-2-naphthols in combination with 2-naphthols or 2-naphthylamines. This distinct activation mode could overcome structural or electronic limitation associated with conventional coupling pathways. Additionally, a novel kinetic resolution protocol of unprotected BINOLs has been established with azodicarboxylates via chiral phosphoric acid(CPA) catalysis. Selectivity factor of up to 175 could be achieved and delivered to both enantiomers in atropisomerically enriched form after a simple work-up.
