Chromium atom photolithography gratings are a promising technology for the development of nanoscale length standard substances due to their high accuracy,uniformity,and consistency.However,the inherent difference betw...Chromium atom photolithography gratings are a promising technology for the development of nanoscale length standard substances due to their high accuracy,uniformity,and consistency.However,the inherent difference between the interaction of positive and negative frequency detuning standing wave field and the atoms can cause a difference in the adjacent peak-to-valley heights of the grating in positive and negative frequency detuning chromium atom lithography,which greatly reduces its accuracy.In this study,we performed a controlled variable growth simulation using the semi-classical theoretical model and Monte Carlo method with trajectory tracking and ballistic deposition methods to investigate the influence of key experimental parameters on the surface growth process of positive and negative frequency detuning atomic lithography gratings.We established a theoretical model based on simulation results and summarized empirical equations to guide the selection of experimental parameters.Our simulations achieved uniform positive and negative frequency detuning atomic lithography gratings with a period of 1/4 of the wavelength corresponding to the atomic transition frequency,and adjacent peak-to-valley heights differing by no more than 2 nm,providing an important theoretical reference for the controllable fabrication of these gratings.展开更多
Choledochocele （also known as type？Ⅲ？ choledochal cyst according to Todani’s classifcation） is a cystic dilation of the distal segment of the common bile duct protru-ding into the duodenal lumen. Cases are rare ...Choledochocele （also known as type？Ⅲ？ choledochal cyst according to Todani’s classifcation） is a cystic dilation of the distal segment of the common bile duct protru-ding into the duodenal lumen. Cases are rare and the etiology remains unclear. It is usually misdiagnosed as peptic ulcer, as in the patient whose case is described here. Multislice spiral computed tomography and magnetic resonance cholangiopancreatography may be comparable to endoscopic retrograde cholangiogra-phy for diagnosis of choledochocele. Both endoscopic therapy and open surgical management are safe options, and size of the cyst plays a role in the decision-making for which approach to apply. A 50-year-old woman admitted to our hospital with upper abdominal pain caused by choledochocele with large size was successfully treated by open surgical management. We present the details of her case in this case report and discuss the recent literature on such cases and their therapeutic management.展开更多
AIM： To construct the recombinant lentivirus expression plasmid, pLenti6/V5-NT4 p53（N 15）-antennapedia （Ant）, and study its effect on HepG2 cells. METHODS： Plasmid pLenti6/V5-NT4 p53（N15）-Ant was constructed i...AIM： To construct the recombinant lentivirus expression plasmid, pLenti6/V5-NT4 p53（N 15）-antennapedia （Ant）, and study its effect on HepG2 cells. METHODS： Plasmid pLenti6/V5-NT4 p53（N15）-Ant was constructed incorporating the following functional regions, including signal peptide sequence and proregion of neurotrophin 4, N-terminal residues 12-26 of p53 and 17 amino acid drosophila carrier protein, Ant. Hepatocellular carcinoma （HepG2） cells were used for transfection. 3-[4,5-climethyl-thiazol-2yl]-2,5 diphenyl tetrazolium bromide （MI-I） assay, lactate dehydrogenase （LDH） release assay, transmission electron microscopy （TEM） and flow cytometric analysis （FCM） were employed to investigate the effects of LV-NT4（Si）- p53（N15）-Ant in vitro on HepG2 cells. In vivo experiment was also performed to investigate the inhibitory effect of LV-NT4（Si）-p53（N15）-Ant on tumor growth in nude mice.RESULTS： LV-NT4（Si）-p53（N15）-Ant significantly suppressed the growth of HepG2 cells. MTT assay showed that the growth of HepG2 cells was mucj more significantly inhibited by LV-NT4（Si）-p53（N15）-Ant than by LV-EGFP. The inhibition rate for HepG2 cell growth in the two groups was 46.9% and 94.5%, respectively, 48 h after infection with LV-NT4（Si）-p53（N15）-Ant, and was 33.9% and 95.8%, respectively, 72 h after infection with LV-NT4（Si）-p53（N15）-Ant （P 〈 0.01）. Light microscopy and TEM showed morphological changes in HepG2 cells infected with LV-NT4（Si）-p53（N15）-Ant, but no significant changes in HepG2 cells infected with LV-EGFR Changes were observed in ultra-structure of HepG2 cells infected with LV-NT4（Si）-p53（N15）-Ant, with degraded membranes, resulting in necrosis. LDH release from HepG2 cells was analyzed at 24, 48, 72 and 96 h after infection with LV-NT4（Si）-p53（N15）-Ant and LV-EGFP, which showed that LDH release was significantly higher in LV-NT4（Si）-p53（N15）-Ant treatment group （682 IU/L） than in control gr展开更多
There is a lack of thermophysical data of heat transfer oil and nano-oil in the high temperature range of 50-300 ℃ for designing and developing heat transfer oil furnace and its heating systems. In the present study,...There is a lack of thermophysical data of heat transfer oil and nano-oil in the high temperature range of 50-300 ℃ for designing and developing heat transfer oil furnace and its heating systems. In the present study, the thermal conductivity values of heat transfer oil and TiO2 nano-oil in the above high temperature range were measured by a newly developed high-temperature thermal conductivity meter. Based on the principle of least square method, the thermal conductivity values obtained from experiments were fitted separately, and the correlation between thermal conductivity and temperature of heat transfer oil and TiO2 nano-oil was obtained. The results show that the thermal conductivity and the increased percentage of thermal conductivity of TiO2 nano-oil are proportional to the increase of particle size and mass fraction of nanoparticles, but thermal conductivity is in reverse proportion to the increase of temperature and the increased percentage of thermal conductivity is less affected by temperature.展开更多
Background：Since 2010,two versions of National Guidelines aimed at promoting the management of ST-segment elevation myocardial infarction （STEMI） have been formulated by the Chinese Society of Cardiology.However,li...Background：Since 2010,two versions of National Guidelines aimed at promoting the management of ST-segment elevation myocardial infarction （STEMI） have been formulated by the Chinese Society of Cardiology.However,little is known about the changes in clinical characteristics,management,and in-hospital outcomes in rural areas.Methods：In the present multicenter,cross-sectional study,participants were enrolled from rural hospitals located in Liaoning province in Northeast China,during two different periods （from June 2009 to June 2010 and from January 2015 to December 2015）.Data collection was conducted using a standardized questionnaire.In total,607 and 637 STEMI patients were recruited in the 2010 and 2015 cohorts,respectively.Results：STEMI patients in rural hospitals were older in the second group （63 years vs.65 years,P =0.039）.We found increases in the prevalence of hypertension,prior percutaneous coronary intervention （PCI）,and prior stroke.Over the past 5 years,the cost during hospitalization almost doubled.The proportion of STEMI patients who underwent emergency reperfusion had significantly increased from 42.34% to 54.47% （P 〈 0.0001）.Concurrently,the proportion of primary PCI increased from 3.62% to 10.52% （P 〈 0.0001）.The past 5 years have also seen marked increases in the use of guideline-recommended drugs and clinical examinations.However,in-hospital mortality and major adverse cardiac events did not significantly change over time （13.01% vs.10.20%,P =0.121;13.34% vs.13.66%,P =0.872）.Conclusions：Despite the great progress that has been made in guideline-recommended therapies,in-hospital outcomes among rural STEMI patients have not significantly improved.Therefore,there is still substantial room for improvement in the quality of care.展开更多
In this editorial,we comment on the article by Zhou et al published in a recent issue.We specifically focus on the crucial roles of ferroptosis and pyroptosis in acute liver failure(ALF),a disease with high mortality ...In this editorial,we comment on the article by Zhou et al published in a recent issue.We specifically focus on the crucial roles of ferroptosis and pyroptosis in acute liver failure(ALF),a disease with high mortality rates.Ferroptosis is the result of increased intracellular reactive oxygen species due to iron accumulation,glutathione(GSH)depletion,and decreased GSH peroxidase 4 activity,while pyroptosis is a procedural cell death mediated by gasdermin D which initiates a sustained inflammatory process.In this review,we describe the characteristics of ferroptosis and pyroptosis,and discuss the involvement of the two cell death modes in the onset and development of ALF.Furthermore,we summarize several interfering methods from the perspective of ferroptosis and pyroptosis for the alleviation of ALF.These observations might provide new targets and a theoretical basis for the treatment of ALF,which are also crucial for improving the prognosis of patients with ALF.展开更多
Ti is regarded as one of the promising grain refiners in cast Al-Li-Cu alloys,but few research works have been done on its independent role.In this study,the effect of Ti on the microstructure evolution and mechanical...Ti is regarded as one of the promising grain refiners in cast Al-Li-Cu alloys,but few research works have been done on its independent role.In this study,the effect of Ti on the microstructure evolution and mechanical properties of cast Al-2Li-2Cu-0.5Mg base alloy was investigated.The results revealed that the grains can be prominently refined with the increase of Ti addition.After adding Ti,high density TiB_(2)-Al_(3)Ti composite particles with a low lattice misfit form as heterogeneous nucleation sites for the α-Al matrix.δ’(Al3Li) and T_(1)(Al_(2)CuLi) precipitates that provide enhanced strength are dominated in the alloys after T6 aging treatment.The average size of both δ’ and half-width of δ’-precipitation free zone(PFZ) decreases gradually with the increase of Ti content.This is because the higher binding energy between Ti atoms and vacancies limits the diffusion efficiency of Li atoms,and thus results in a higher ductility.Additionally,no nano-sized Al_(3)Ti or core-shell structure of Al_(3)(Li,Ti) particles are found.The tensile property test results indicate that the Al-2Li-2Cu-0.5Mg alloy achieves optimal properties after aging at 175 °C for 32 h when 0.15wt.% Ti is added.It exhibits a yield strength of 352±5 MPa,an ultimate tensile strength of 423±6 MPa,and an elongation of(3±0.4)%.These findings are expected to offer a reliable theoretical guidance for the industrial composition design of the Al-Li-Cu series cast alloys.展开更多
Cu2O/TiOa/Pt three-layer films were deposited on glass substrates using magnetron sputtering method. The surface morphology and the optical properties of the composite film were characterized by X-ray diffraction （XR...Cu2O/TiOa/Pt three-layer films were deposited on glass substrates using magnetron sputtering method. The surface morphology and the optical properties of the composite film were characterized by X-ray diffraction （XRD）, scanning electron microscopy （SEM）, ultraviolet- visible spectroscopy （UV-Vis） and photoluminescence spectroscopy （PL）. The photocatalytic activity of the samples was evaluated by the photocatalytic degradation of methyl orange （MO） aqueous solution under visible light irradiation. The results indicate that the Cu2O/TiO2/Pt composite films are made up of three layers which are Pt layer, anatase-TiO2 layer and Cu2O layer from bottom to top. The surface of the films is even and composed of regular-shaped spherical particles. The photocatalytic activity of the Cu2O/TiO2/Pt three-layer film is much higher than that of the Cu2O/TiO2 double-layer film. Such enhancement is ascribed to the presence of Pt layer, which further inhibits the photogenerated electron-hole recombination, prolongs the lifetime of the photogenerated carriers, increases the quantum efficiency and hence improves the photocatalytic activity of the film effectively.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant No.62075165)the National Key Research and Development Program of China(Grant Nos.2022YFF0607600 and 2022YFF0605502)+3 种基金the Special Development Funds for Major Projects of Shanghai Zhangjiang National Independent Innovation Demonstration Zone(Grant No.ZJ2021ZD008)the Shanghai Natural Science Foundation(Grant No.21ZR1483100)the Shanghai Academic/Technology Research Leader(Grant No.21XD1425000)the Opening Fund of Shanghai Key Laboratory of Online Detection and Control Technology(Grant No.ZX2020101)。
文摘Chromium atom photolithography gratings are a promising technology for the development of nanoscale length standard substances due to their high accuracy,uniformity,and consistency.However,the inherent difference between the interaction of positive and negative frequency detuning standing wave field and the atoms can cause a difference in the adjacent peak-to-valley heights of the grating in positive and negative frequency detuning chromium atom lithography,which greatly reduces its accuracy.In this study,we performed a controlled variable growth simulation using the semi-classical theoretical model and Monte Carlo method with trajectory tracking and ballistic deposition methods to investigate the influence of key experimental parameters on the surface growth process of positive and negative frequency detuning atomic lithography gratings.We established a theoretical model based on simulation results and summarized empirical equations to guide the selection of experimental parameters.Our simulations achieved uniform positive and negative frequency detuning atomic lithography gratings with a period of 1/4 of the wavelength corresponding to the atomic transition frequency,and adjacent peak-to-valley heights differing by no more than 2 nm,providing an important theoretical reference for the controllable fabrication of these gratings.
文摘Choledochocele （also known as type？Ⅲ？ choledochal cyst according to Todani’s classifcation） is a cystic dilation of the distal segment of the common bile duct protru-ding into the duodenal lumen. Cases are rare and the etiology remains unclear. It is usually misdiagnosed as peptic ulcer, as in the patient whose case is described here. Multislice spiral computed tomography and magnetic resonance cholangiopancreatography may be comparable to endoscopic retrograde cholangiogra-phy for diagnosis of choledochocele. Both endoscopic therapy and open surgical management are safe options, and size of the cyst plays a role in the decision-making for which approach to apply. A 50-year-old woman admitted to our hospital with upper abdominal pain caused by choledochocele with large size was successfully treated by open surgical management. We present the details of her case in this case report and discuss the recent literature on such cases and their therapeutic management.
基金Supported by The National Natural Science Foundation of China,No.30471942the Key Science Research Project of Shaanxi Province,No.2004k11-G3
文摘AIM： To construct the recombinant lentivirus expression plasmid, pLenti6/V5-NT4 p53（N 15）-antennapedia （Ant）, and study its effect on HepG2 cells. METHODS： Plasmid pLenti6/V5-NT4 p53（N15）-Ant was constructed incorporating the following functional regions, including signal peptide sequence and proregion of neurotrophin 4, N-terminal residues 12-26 of p53 and 17 amino acid drosophila carrier protein, Ant. Hepatocellular carcinoma （HepG2） cells were used for transfection. 3-[4,5-climethyl-thiazol-2yl]-2,5 diphenyl tetrazolium bromide （MI-I） assay, lactate dehydrogenase （LDH） release assay, transmission electron microscopy （TEM） and flow cytometric analysis （FCM） were employed to investigate the effects of LV-NT4（Si）- p53（N15）-Ant in vitro on HepG2 cells. In vivo experiment was also performed to investigate the inhibitory effect of LV-NT4（Si）-p53（N15）-Ant on tumor growth in nude mice.RESULTS： LV-NT4（Si）-p53（N15）-Ant significantly suppressed the growth of HepG2 cells. MTT assay showed that the growth of HepG2 cells was mucj more significantly inhibited by LV-NT4（Si）-p53（N15）-Ant than by LV-EGFP. The inhibition rate for HepG2 cell growth in the two groups was 46.9% and 94.5%, respectively, 48 h after infection with LV-NT4（Si）-p53（N15）-Ant, and was 33.9% and 95.8%, respectively, 72 h after infection with LV-NT4（Si）-p53（N15）-Ant （P 〈 0.01）. Light microscopy and TEM showed morphological changes in HepG2 cells infected with LV-NT4（Si）-p53（N15）-Ant, but no significant changes in HepG2 cells infected with LV-EGFR Changes were observed in ultra-structure of HepG2 cells infected with LV-NT4（Si）-p53（N15）-Ant, with degraded membranes, resulting in necrosis. LDH release from HepG2 cells was analyzed at 24, 48, 72 and 96 h after infection with LV-NT4（Si）-p53（N15）-Ant and LV-EGFP, which showed that LDH release was significantly higher in LV-NT4（Si）-p53（N15）-Ant treatment group （682 IU/L） than in control gr
基金Project(51346007) supported by the National Natural Science Foundation of China
文摘There is a lack of thermophysical data of heat transfer oil and nano-oil in the high temperature range of 50-300 ℃ for designing and developing heat transfer oil furnace and its heating systems. In the present study, the thermal conductivity values of heat transfer oil and TiO2 nano-oil in the above high temperature range were measured by a newly developed high-temperature thermal conductivity meter. Based on the principle of least square method, the thermal conductivity values obtained from experiments were fitted separately, and the correlation between thermal conductivity and temperature of heat transfer oil and TiO2 nano-oil was obtained. The results show that the thermal conductivity and the increased percentage of thermal conductivity of TiO2 nano-oil are proportional to the increase of particle size and mass fraction of nanoparticles, but thermal conductivity is in reverse proportion to the increase of temperature and the increased percentage of thermal conductivity is less affected by temperature.
文摘Background：Since 2010,two versions of National Guidelines aimed at promoting the management of ST-segment elevation myocardial infarction （STEMI） have been formulated by the Chinese Society of Cardiology.However,little is known about the changes in clinical characteristics,management,and in-hospital outcomes in rural areas.Methods：In the present multicenter,cross-sectional study,participants were enrolled from rural hospitals located in Liaoning province in Northeast China,during two different periods （from June 2009 to June 2010 and from January 2015 to December 2015）.Data collection was conducted using a standardized questionnaire.In total,607 and 637 STEMI patients were recruited in the 2010 and 2015 cohorts,respectively.Results：STEMI patients in rural hospitals were older in the second group （63 years vs.65 years,P =0.039）.We found increases in the prevalence of hypertension,prior percutaneous coronary intervention （PCI）,and prior stroke.Over the past 5 years,the cost during hospitalization almost doubled.The proportion of STEMI patients who underwent emergency reperfusion had significantly increased from 42.34% to 54.47% （P 〈 0.0001）.Concurrently,the proportion of primary PCI increased from 3.62% to 10.52% （P 〈 0.0001）.The past 5 years have also seen marked increases in the use of guideline-recommended drugs and clinical examinations.However,in-hospital mortality and major adverse cardiac events did not significantly change over time （13.01% vs.10.20%,P =0.121;13.34% vs.13.66%,P =0.872）.Conclusions：Despite the great progress that has been made in guideline-recommended therapies,in-hospital outcomes among rural STEMI patients have not significantly improved.Therefore,there is still substantial room for improvement in the quality of care.
文摘In this editorial,we comment on the article by Zhou et al published in a recent issue.We specifically focus on the crucial roles of ferroptosis and pyroptosis in acute liver failure(ALF),a disease with high mortality rates.Ferroptosis is the result of increased intracellular reactive oxygen species due to iron accumulation,glutathione(GSH)depletion,and decreased GSH peroxidase 4 activity,while pyroptosis is a procedural cell death mediated by gasdermin D which initiates a sustained inflammatory process.In this review,we describe the characteristics of ferroptosis and pyroptosis,and discuss the involvement of the two cell death modes in the onset and development of ALF.Furthermore,we summarize several interfering methods from the perspective of ferroptosis and pyroptosis for the alleviation of ALF.These observations might provide new targets and a theoretical basis for the treatment of ALF,which are also crucial for improving the prognosis of patients with ALF.
基金financially supported by the National Natural Science Foundation of China (Nos.51821001 and 51871148)。
文摘Ti is regarded as one of the promising grain refiners in cast Al-Li-Cu alloys,but few research works have been done on its independent role.In this study,the effect of Ti on the microstructure evolution and mechanical properties of cast Al-2Li-2Cu-0.5Mg base alloy was investigated.The results revealed that the grains can be prominently refined with the increase of Ti addition.After adding Ti,high density TiB_(2)-Al_(3)Ti composite particles with a low lattice misfit form as heterogeneous nucleation sites for the α-Al matrix.δ’(Al3Li) and T_(1)(Al_(2)CuLi) precipitates that provide enhanced strength are dominated in the alloys after T6 aging treatment.The average size of both δ’ and half-width of δ’-precipitation free zone(PFZ) decreases gradually with the increase of Ti content.This is because the higher binding energy between Ti atoms and vacancies limits the diffusion efficiency of Li atoms,and thus results in a higher ductility.Additionally,no nano-sized Al_(3)Ti or core-shell structure of Al_(3)(Li,Ti) particles are found.The tensile property test results indicate that the Al-2Li-2Cu-0.5Mg alloy achieves optimal properties after aging at 175 °C for 32 h when 0.15wt.% Ti is added.It exhibits a yield strength of 352±5 MPa,an ultimate tensile strength of 423±6 MPa,and an elongation of(3±0.4)%.These findings are expected to offer a reliable theoretical guidance for the industrial composition design of the Al-Li-Cu series cast alloys.
基金financially supported by the National Natural Science Foundation of China (No.51301118)the Projects of International Cooperation in Shanxi (No.2014081002)the Scientific and Technological Innovation Programs of Higher Education Institutions in Shanxi (No.2013108)
文摘Cu2O/TiOa/Pt three-layer films were deposited on glass substrates using magnetron sputtering method. The surface morphology and the optical properties of the composite film were characterized by X-ray diffraction （XRD）, scanning electron microscopy （SEM）, ultraviolet- visible spectroscopy （UV-Vis） and photoluminescence spectroscopy （PL）. The photocatalytic activity of the samples was evaluated by the photocatalytic degradation of methyl orange （MO） aqueous solution under visible light irradiation. The results indicate that the Cu2O/TiO2/Pt composite films are made up of three layers which are Pt layer, anatase-TiO2 layer and Cu2O layer from bottom to top. The surface of the films is even and composed of regular-shaped spherical particles. The photocatalytic activity of the Cu2O/TiO2/Pt three-layer film is much higher than that of the Cu2O/TiO2 double-layer film. Such enhancement is ascribed to the presence of Pt layer, which further inhibits the photogenerated electron-hole recombination, prolongs the lifetime of the photogenerated carriers, increases the quantum efficiency and hence improves the photocatalytic activity of the film effectively.
