Integrated conductive elastomers with excellent mechanical performance,stable high conductivity,self-healing capabilities,and high transparency are critical for advancing wearable devices.Nevertheless,achieving an opt...Integrated conductive elastomers with excellent mechanical performance,stable high conductivity,self-healing capabilities,and high transparency are critical for advancing wearable devices.Nevertheless,achieving an optimal balance among these properties remains a significant challenge.Herein,through in situ free-radical copolymerization of 2-[2-(2-methoxyethoxy)ethoxy]ethyl acrylate(TEEA)and vinylimidazole(VI)in the presence of polyethylene glycol(PEG;Mn=400),tough P(TEEA-co-VI)/PEG elastomers with multiple functionalities were prepared,in which P(TEEA-co-VI)was dynamically cross-linked by imidazole-Zn^(2+)metal coordination crosslinks,and physically blended with PEG as polymer electrolyte to form a homogeneous mixture.Notably,Zn^(2+)has a negligible impact on the polymerization process,allowing for the in situ formation of numerous imidazole-Zn^(2+)metal coordination crosslinks,which can effectively dissipate energy upon stretching to largely reinforce the elastomers.The obtained P(TEEA-co-VI)/PEG elastomers exhibited a high toughness of 10.0 MJ·m^(-3) with a high tensile strength of 3.3 MPa and a large elongation at break of 645%,along with outstanding self-healing capabilities due to the dynamic coordination crosslinks.Moreover,because of the miscibility of PEG with PTEEA copolymer matrix,and Li+can form weak coordination interactions with the ethoxy(EO)units in PEG and PTEEA,acting as a bridge to integrate PEG into the elastomer network.The resulted P(TEEA-co-VI)/PEG elastomers showed high transparency(92%)and stable high conductivity of 1.09×10_(-4) S·cm^(-1).In summary,the obtained elastomers exhibited a well-balanced combination of high toughness,high ionic conductivity,excellent self-healing capabilities,and high transparency,making them promising for applications in flexible strain sensors.展开更多
Objective To investigate the influence of electroacupuncture(EA)on ghrelin and the phosphoinositide 3-kinase/protein kinase B/endothelial nitric oxide synthase(PI3K/Akt/eNOS)signaling pathway in spontaneously hyperten...Objective To investigate the influence of electroacupuncture(EA)on ghrelin and the phosphoinositide 3-kinase/protein kinase B/endothelial nitric oxide synthase(PI3K/Akt/eNOS)signaling pathway in spontaneously hypertensive rats(SHRs).Methods Eight Wistar-Kyoto rats were used as the healthy blood pressure(BP)control(normal group),and 32 SHRs were randomized into model group,EA group,EA plus ghrelin group(EA+G group),and EA plus PF04628935 group(a potent ghrelin receptor blocker;EA+P group)using a random number table.Rats in the normal group and model group did not receive treatment,but were immobilized for 20 min per day,5 times a week,for 4 continuous weeks.SHRs in the EA group,EA+G group and EA+P group were immobilized and given EA treatment in 20 min sessions,5 times per week,for 4 weeks.Additionally,1 h before EA,SHRs in the EA+G group and EA+P group were intraperitoneally injected with ghrelin or PF04628935,respectively,for 4 weeks.The tail-cuff method was used to measure BP.After the 4-week intervention,the rats were sacrificed by cervical dislocation,and pathological morphology of the abdominal aorta was observed using hematoxylin-eosin(HE)staining.Enzyme-linked immunosorbent assay(ELISA)was used to detect the levels of ghrelin,nitric oxide(NO),endothelin-1(ET-1)and thromboxane A2(TXA2)in the serum.Isolated thoracic aortic ring experiment was performed to evaluate vasorelaxation.Western blot was used to measure the expression of PI3K,Akt,phosphorylated Akt(p-Akt)and eNOS proteins in the abdominal aorta.Further,quantitative real-time polymerase chain reaction(qRT-PCR)was conducted to measure the relative levels of mRNA expression for PI3K,Akt and eNOS in the abdominal aorta.Results EA significantly reduced the systolic BP(SBP)and diastolic BP(DBP)(P<0.05).HE staining showed that EA improved the morphology of the vascular endothelium to some extent.Results of ELISA indicated that higher concentrations of ghrelin and NO,and lower concentrations of ET-1 and TXA2 were present in the EA group(P<0.05).The isolated thoracic aortic ring experiment demonstrated that the vasodilation capacity of the thoracic aorta increased in the EA group.Results of Western blot and qRT-PCR showed that EA increased the abundance of PI3K,p-Akt/Akt and eNOS proteins,as well as expression levels of PI3K,Akt and eNOS mRNAs(P<0.05).In the EA+G group,SBP and DBP decreased(P<0.05),ghrelin concentrations increased(P<0.05),and the concentrations of ET-1 and TXA2 decreased(P<0.05),relative to the EA group.In addition,the levels of PI3K and eNOS proteins,the p-Akt/Akt ratio,and the expression of PI3K,Akt and eNOS mRNAs increased significantly in the EA+G group(P<0.05),while PF04628935 reversed these effects.Conclusion EA effectively reduced BP and protected the vascular endothelium,and these effects may be linked to promoting the release of ghrelin and activation of the PI3K/Akt/eNOS signaling pathway.展开更多
Liquid metals(LM)refer to Ga-based alloys with low melting points such as Eutectic GaInSn alloys(EGaInSn),which have excellent fluidity,flexibility and low toxicity at room temperature.In this work,by incorporating EG...Liquid metals(LM)refer to Ga-based alloys with low melting points such as Eutectic GaInSn alloys(EGaInSn),which have excellent fluidity,flexibility and low toxicity at room temperature.In this work,by incorporating EGaInSn into poly(acrylic acid)(PAA)hydrogels as dynamic crosslinkers and effective energy-dissipating units,tough and strong PAA-LM hydrogels are prepared through the interactions between the oxide layers on the surface of LM and carboxyl groups of PAA chains.Moreover,owing to the fluidity of LM,one LM droplet as a cross-linking point may change its shape or break into more and smaller droplets in the hydrogels upon stretching.Then hydrogels with self-adaptive networks can be fabricated by mechanical training through cyclic stretch at a certain elongation.Thus,the networks of the hydrogels are further homogenized,and the hydrogels are significantly toughened during the training due to the increased cross-linking density from the larger number of smaller LM droplets.After a 5-cycle training at the maximum strain of 500%and 24 h recovering,the tensile strength and initial modulus of the PAA-LM hydrogels can be increased from 355 kPa to 597 kPa and 71 kPa to 166 kPa,respectively,while the elongation at break only decreases from 1491%to 1034%.展开更多
BACKGROUND Many studies have demonstrated the benefit of complete multivessel revascularization versus culprit-only intervention in patients of ST-segment elevation myocardial infarction(STEMI)and multivessel coronary...BACKGROUND Many studies have demonstrated the benefit of complete multivessel revascularization versus culprit-only intervention in patients of ST-segment elevation myocardial infarction(STEMI)and multivessel coronary artery disease.However,only a few single-center retrospective studies were performed on small Chinese cohorts.Our study aims to demonstrate the advantage of multivessel percutaneous intervention(PCI)strategy on 30-day in-hospital outcomes to patients with STEMI and multivessel disease in larger Chinese population.METHODS From the Improving Care for Cardiovascular Disease in China-Acute Coronary Syndrome(CCC-ACS)project,5935 patients with STEMI and multivessel disease undergoing PCI and hospitalized for fewer than 30 days were analyzed.After 5:1 propensity score matching,3577 patients with culprit-only PCI and 877 with in-hospital multivessel PCI were included.The primary outcome was major adverse cardiovascular and cerebrovascular event(MACCE),defined as a composite of myocardial infarction,all-cause death,stent thrombosis,heart failure,and stroke.RESULTS Multivariable logistic regression analysis revealed that in-hospital multivessel PCI was associated with lower risk of 30-day MACCE(adjusted OR=0.75,95%CI:0.57-0.98,P=0.032)than culprit-only PCI and conferred no increased risk of allcause death,myocardial infarction,stent thrombosis,stroke,or bleeding.Subgroup analysis showed that MACCE reduction was observed more often from patients with trans-femoral access(OR=0.34,95%CI:0.15-0.74)than with trans-radial access(OR=0.87,95%CI:0.66-1.16,P for interaction=0.017).CONCLUSIONS The in-hospital multivessel PCI strategy was associated with a lower risk of 30-day MACCE than culprit-only PCI in patients with STEMI and multivessel coronary artery disease.展开更多
Lunar Penetrating Radar （LPR） is one of the important scientific instru- ments onboard the Chang＇e-3 spacecraft. Its scientific goals are the mapping of lunar regolith and detection of subsurface geologic structure...Lunar Penetrating Radar （LPR） is one of the important scientific instru- ments onboard the Chang＇e-3 spacecraft. Its scientific goals are the mapping of lunar regolith and detection of subsurface geologic structures. This paper describes the goals of the mission, as well as the basic principles, design, composition and achievements of the LPR. Finally, experiments on a glacier and the lunar surface are analyzed.展开更多
A series of the electrochemical and long-term corrosion tests was carried out in a 3.5 wt% Na2SO4 solution on thermal-sprayed WC-17Co and WC-10Co-4Cr cermet coatings in order to examine the effect of composition of bi...A series of the electrochemical and long-term corrosion tests was carried out in a 3.5 wt% Na2SO4 solution on thermal-sprayed WC-17Co and WC-10Co-4Cr cermet coatings in order to examine the effect of composition of binder materials on the corrosion behavior. The results reveal that the overall corrosion resistance of the WC-17Co coating is inferior to that of the WC-Co-Cr coatings due to the corrosion of binder materials which induce WC particles to fall off. CoO and WO3 oxide films form on the surface of WC-17Co coating in Na2SO4 solution electrochemical corrosion process, which will protect the coating in the process of corrosion. Cr2O3 oxide film formed on the WC-10Co-4Cr coating surface has a strong hindered role to corrosion. The corrosion mechanism of WC-17Co coating in Na2SO4 solution is entire corrosion of Co matrix, while it is film-hole corrosion mechanism for WC-10Co-4Cr coating.展开更多
To obtain environmentally friendly,integrated and miniaturized gas sensors for the increasing request for the Internet of Things industry and other relative areas,the ultra-thin CoO_(x)/Zn O heterogeneous film with ac...To obtain environmentally friendly,integrated and miniaturized gas sensors for the increasing request for the Internet of Things industry and other relative areas,the ultra-thin CoO_(x)/Zn O heterogeneous film with active interfacial sites was in-situ deposited on micro-electro-mechanical systems(MEMS)as H_(2)S sensor.Atomic layer deposition(ALD)was employed to in-situ fabricate the uniform Zn O thin film.ALD CoO_(x)was deposited on ZnO surface to obtain CoO_(x)/Zn O heterojunction and active interfacial sites.The ultra-thin film(20 nm)with 50 ALD Co O_(x)decorated on 250 ALD Zn O displays excellent sensing performance,including very high response(4.45@200×10^(-9))and selectivity to H_(2)S with a limit of detection(LOD)of 0.38×10^(-9),long-term sensing stability,high response/recovery performance(7.5 s/15.7 s)and mechanical strength at 230。C.Reasons for the high sensing performance of CoO_(x)/Zn O have been confirmed by series of characterizations and density functional theory(DFT)calculation.Heterojunction film thickness with Debye length,the oxygen vacancies and the synergistic effect of active interfacial sites are main reasons for the high sensing performance.The strategy by fabrication of CoO_(x)/Zn O heterogeneous film within Debye length and employing synergistic effect of active interfacial sites offers a promising route for the design of environmentally friendly gas sensors.Furthermore,the ALD technique offers a facile in-situ strategy and high-throughput fabrication of MEMS gas sensors.展开更多
The diagnosis of pulmonary hypertension(PH) should be made by combining clinical manifestations and echocardiographic probability.[1] Following the confirmation of PH, the classification should begin with the more com...The diagnosis of pulmonary hypertension(PH) should be made by combining clinical manifestations and echocardiographic probability.[1] Following the confirmation of PH, the classification should begin with the more common groups [group 2(PH due to left heart disease) and group 3(PH due to lung diseases and/or hypoxia)], then group 4(chronic thromboembolic PH and other pulmonary artery obstructions) and finally group 1(pulmonary arterial hypertension) and group 5(PH with unclear and/or multifactorial mechanisms).[1] In this case, we demonstrate a rare scenario of obstruction-caused group 4 PH.展开更多
We report the radio observations of the eclipsing black widow pulsar J1720-0534, a 3.26 ms pulsar in orbit with a low mass companion of mass 0.029 to 0.034 M⊙. We obtain the phase-connected timing ephemeris and polar...We report the radio observations of the eclipsing black widow pulsar J1720-0534, a 3.26 ms pulsar in orbit with a low mass companion of mass 0.029 to 0.034 M⊙. We obtain the phase-connected timing ephemeris and polarization profile of this millisecond pulsar(MSP) using the Five-hundred-meter Aperture Spherical radio Telescope(FAST), the Green Bank Telescope(GBT), and the Parkes Telescope. For the first time from such a system, an oscillatory polarization angle change was observed from a particular eclipse egress with partial depolarization, indicating 10-milliGauss-level reciprocating magnetic fields oscillating in a length scale of 5 ×10^(3)km(assuming an orbital inclination angle of 90°) outside the companion's magnetosphere. The dispersion measure variation observed during the ingresses and egresses shows the rapid raising of the electron density in the shock boundary between the companion's magnetosphere and the surrounding pulsar wind. We suggest that the observed oscillatory magnetic fields originate from the pulsar wind outside the companion's magnetosphere.展开更多
Dear editor,Wellens syndrome is characterized by electrocardiography(ECG)patterns of the biphasic or inverted T wave in the precordial leads with normal R wave progression and absence of Q waves,[1,2]which indicates o...Dear editor,Wellens syndrome is characterized by electrocardiography(ECG)patterns of the biphasic or inverted T wave in the precordial leads with normal R wave progression and absence of Q waves,[1,2]which indicates occlusive lesions of the proximal left anterior descending(LAD)coronary artery and warrants.[1]These ECG changes usually occur during a pain-free interval and turn to a fatal consequence if without urgent intervention therapy.[1,3]However,in some cases,coronary stenosis was absent and ECG patterns manifested as Wellens syndrome,which was defined as pseudo-Wellens syndrome.展开更多
BACKGROUND Arterial stiffness,as assessed by aortic ultrasound and pulse wave velocity,is associated with incident hypertension.However,there is still no consensus on whether the augmentation index(AI)affects new onse...BACKGROUND Arterial stiffness,as assessed by aortic ultrasound and pulse wave velocity,is associated with incident hypertension.However,there is still no consensus on whether the augmentation index(AI)affects new onset of hypertension.This study investigated the relationship of radial AI(r AI)and incident hypertension in a Chinese community-based population without hypertension at baseline.METHOD A total of 1,615 Chinese non-hypertensive participants from an atherosclerosis cohort in Beijing,China were included in our analysis.Baseline r AI normalized to heart rate of 75 beats/min(r AIp75)was obtained using HEM-9000 AI.New-onset hypertension was defined as blood pressure≥140/90 mm Hg or self-reported hypertension or taking anti-hypertensive medications at the follow up survey.Multivariate regression models were used to evaluate the impact of r AIp75 on the risk of new-onset hypertension.RESULTS After a mean 2.35-year follow-up,213(13.19%)participants developed incident hypertension.No significant relation between r AIp75 and incident hypertension was observed in the whole population after adjustment for possible confounders(adjusted odds ratio(OR)and 95%confidence interval(CI):1.09[0.95-1.27];P=0.2260).However,r AIp75 was significantly associated with incident hypertension in women,but not in men(adjusted OR and 95%CI:1.29[1.06-1.56],P=0.0113 for women;0.91[0.72-1.15],P=0.4244 for men;P for interaction=0.0133).CONCLUSIONS Sex modified the effect of the r AI on incident hypertension in a Chinese,community-based,non-hypertensive population.Screening of the r AI could be considered in women with a high risk of hypertension for the purpose of primary intervention.展开更多
基金supported by the National Natural Science Foundation of China(Nos.52273023,51973103,and 21774069).
文摘Integrated conductive elastomers with excellent mechanical performance,stable high conductivity,self-healing capabilities,and high transparency are critical for advancing wearable devices.Nevertheless,achieving an optimal balance among these properties remains a significant challenge.Herein,through in situ free-radical copolymerization of 2-[2-(2-methoxyethoxy)ethoxy]ethyl acrylate(TEEA)and vinylimidazole(VI)in the presence of polyethylene glycol(PEG;Mn=400),tough P(TEEA-co-VI)/PEG elastomers with multiple functionalities were prepared,in which P(TEEA-co-VI)was dynamically cross-linked by imidazole-Zn^(2+)metal coordination crosslinks,and physically blended with PEG as polymer electrolyte to form a homogeneous mixture.Notably,Zn^(2+)has a negligible impact on the polymerization process,allowing for the in situ formation of numerous imidazole-Zn^(2+)metal coordination crosslinks,which can effectively dissipate energy upon stretching to largely reinforce the elastomers.The obtained P(TEEA-co-VI)/PEG elastomers exhibited a high toughness of 10.0 MJ·m^(-3) with a high tensile strength of 3.3 MPa and a large elongation at break of 645%,along with outstanding self-healing capabilities due to the dynamic coordination crosslinks.Moreover,because of the miscibility of PEG with PTEEA copolymer matrix,and Li+can form weak coordination interactions with the ethoxy(EO)units in PEG and PTEEA,acting as a bridge to integrate PEG into the elastomer network.The resulted P(TEEA-co-VI)/PEG elastomers showed high transparency(92%)and stable high conductivity of 1.09×10_(-4) S·cm^(-1).In summary,the obtained elastomers exhibited a well-balanced combination of high toughness,high ionic conductivity,excellent self-healing capabilities,and high transparency,making them promising for applications in flexible strain sensors.
基金This study was supported by the National Natural Science Foundation of China(No.81704137.No.82074516,and No.82104976)sichuan Science and Technology Department(No.2019YJ0331)Chengdu University of Traditional Chinese Medicine(No.ZRQN2020022).
文摘Objective To investigate the influence of electroacupuncture(EA)on ghrelin and the phosphoinositide 3-kinase/protein kinase B/endothelial nitric oxide synthase(PI3K/Akt/eNOS)signaling pathway in spontaneously hypertensive rats(SHRs).Methods Eight Wistar-Kyoto rats were used as the healthy blood pressure(BP)control(normal group),and 32 SHRs were randomized into model group,EA group,EA plus ghrelin group(EA+G group),and EA plus PF04628935 group(a potent ghrelin receptor blocker;EA+P group)using a random number table.Rats in the normal group and model group did not receive treatment,but were immobilized for 20 min per day,5 times a week,for 4 continuous weeks.SHRs in the EA group,EA+G group and EA+P group were immobilized and given EA treatment in 20 min sessions,5 times per week,for 4 weeks.Additionally,1 h before EA,SHRs in the EA+G group and EA+P group were intraperitoneally injected with ghrelin or PF04628935,respectively,for 4 weeks.The tail-cuff method was used to measure BP.After the 4-week intervention,the rats were sacrificed by cervical dislocation,and pathological morphology of the abdominal aorta was observed using hematoxylin-eosin(HE)staining.Enzyme-linked immunosorbent assay(ELISA)was used to detect the levels of ghrelin,nitric oxide(NO),endothelin-1(ET-1)and thromboxane A2(TXA2)in the serum.Isolated thoracic aortic ring experiment was performed to evaluate vasorelaxation.Western blot was used to measure the expression of PI3K,Akt,phosphorylated Akt(p-Akt)and eNOS proteins in the abdominal aorta.Further,quantitative real-time polymerase chain reaction(qRT-PCR)was conducted to measure the relative levels of mRNA expression for PI3K,Akt and eNOS in the abdominal aorta.Results EA significantly reduced the systolic BP(SBP)and diastolic BP(DBP)(P<0.05).HE staining showed that EA improved the morphology of the vascular endothelium to some extent.Results of ELISA indicated that higher concentrations of ghrelin and NO,and lower concentrations of ET-1 and TXA2 were present in the EA group(P<0.05).The isolated thoracic aortic ring experiment demonstrated that the vasodilation capacity of the thoracic aorta increased in the EA group.Results of Western blot and qRT-PCR showed that EA increased the abundance of PI3K,p-Akt/Akt and eNOS proteins,as well as expression levels of PI3K,Akt and eNOS mRNAs(P<0.05).In the EA+G group,SBP and DBP decreased(P<0.05),ghrelin concentrations increased(P<0.05),and the concentrations of ET-1 and TXA2 decreased(P<0.05),relative to the EA group.In addition,the levels of PI3K and eNOS proteins,the p-Akt/Akt ratio,and the expression of PI3K,Akt and eNOS mRNAs increased significantly in the EA+G group(P<0.05),while PF04628935 reversed these effects.Conclusion EA effectively reduced BP and protected the vascular endothelium,and these effects may be linked to promoting the release of ghrelin and activation of the PI3K/Akt/eNOS signaling pathway.
基金financially supported by the National Natural Science Foundation of China(Nos.52273023,21774069,51633003 and 21474058)。
文摘Liquid metals(LM)refer to Ga-based alloys with low melting points such as Eutectic GaInSn alloys(EGaInSn),which have excellent fluidity,flexibility and low toxicity at room temperature.In this work,by incorporating EGaInSn into poly(acrylic acid)(PAA)hydrogels as dynamic crosslinkers and effective energy-dissipating units,tough and strong PAA-LM hydrogels are prepared through the interactions between the oxide layers on the surface of LM and carboxyl groups of PAA chains.Moreover,owing to the fluidity of LM,one LM droplet as a cross-linking point may change its shape or break into more and smaller droplets in the hydrogels upon stretching.Then hydrogels with self-adaptive networks can be fabricated by mechanical training through cyclic stretch at a certain elongation.Thus,the networks of the hydrogels are further homogenized,and the hydrogels are significantly toughened during the training due to the increased cross-linking density from the larger number of smaller LM droplets.After a 5-cycle training at the maximum strain of 500%and 24 h recovering,the tensile strength and initial modulus of the PAA-LM hydrogels can be increased from 355 kPa to 597 kPa and 71 kPa to 166 kPa,respectively,while the elongation at break only decreases from 1491%to 1034%.
基金We thank all hospitals and staff participating in the Improving Care for Cardiovascular Disease in China-Acute Coronary Syndrome(CCC-ACS)project.The CCC-ACS Project is a collaborative project of the American Heart Association and the Chinese Society of Cardiology.The American Heart Association received funding from Pfizer through an independent grant for learning and change and AstraZeneca as a quality improvement initiative.
文摘BACKGROUND Many studies have demonstrated the benefit of complete multivessel revascularization versus culprit-only intervention in patients of ST-segment elevation myocardial infarction(STEMI)and multivessel coronary artery disease.However,only a few single-center retrospective studies were performed on small Chinese cohorts.Our study aims to demonstrate the advantage of multivessel percutaneous intervention(PCI)strategy on 30-day in-hospital outcomes to patients with STEMI and multivessel disease in larger Chinese population.METHODS From the Improving Care for Cardiovascular Disease in China-Acute Coronary Syndrome(CCC-ACS)project,5935 patients with STEMI and multivessel disease undergoing PCI and hospitalized for fewer than 30 days were analyzed.After 5:1 propensity score matching,3577 patients with culprit-only PCI and 877 with in-hospital multivessel PCI were included.The primary outcome was major adverse cardiovascular and cerebrovascular event(MACCE),defined as a composite of myocardial infarction,all-cause death,stent thrombosis,heart failure,and stroke.RESULTS Multivariable logistic regression analysis revealed that in-hospital multivessel PCI was associated with lower risk of 30-day MACCE(adjusted OR=0.75,95%CI:0.57-0.98,P=0.032)than culprit-only PCI and conferred no increased risk of allcause death,myocardial infarction,stent thrombosis,stroke,or bleeding.Subgroup analysis showed that MACCE reduction was observed more often from patients with trans-femoral access(OR=0.34,95%CI:0.15-0.74)than with trans-radial access(OR=0.87,95%CI:0.66-1.16,P for interaction=0.017).CONCLUSIONS The in-hospital multivessel PCI strategy was associated with a lower risk of 30-day MACCE than culprit-only PCI in patients with STEMI and multivessel coronary artery disease.
基金funded by the second phase of the Chinese Lunar Exploration Program
文摘Lunar Penetrating Radar （LPR） is one of the important scientific instru- ments onboard the Chang＇e-3 spacecraft. Its scientific goals are the mapping of lunar regolith and detection of subsurface geologic structures. This paper describes the goals of the mission, as well as the basic principles, design, composition and achievements of the LPR. Finally, experiments on a glacier and the lunar surface are analyzed.
基金financially supported by the Fundamental Research Funds for the Central Universities (Nos.SWJTU11BR203 and SWJTU12CX047)the National Key Technology R&D Program of the Ministry of Science and Technology (No. 2012BAE06B02)
文摘A series of the electrochemical and long-term corrosion tests was carried out in a 3.5 wt% Na2SO4 solution on thermal-sprayed WC-17Co and WC-10Co-4Cr cermet coatings in order to examine the effect of composition of binder materials on the corrosion behavior. The results reveal that the overall corrosion resistance of the WC-17Co coating is inferior to that of the WC-Co-Cr coatings due to the corrosion of binder materials which induce WC particles to fall off. CoO and WO3 oxide films form on the surface of WC-17Co coating in Na2SO4 solution electrochemical corrosion process, which will protect the coating in the process of corrosion. Cr2O3 oxide film formed on the WC-10Co-4Cr coating surface has a strong hindered role to corrosion. The corrosion mechanism of WC-17Co coating in Na2SO4 solution is entire corrosion of Co matrix, while it is film-hole corrosion mechanism for WC-10Co-4Cr coating.
基金financially supported by the National Key Research and Development Program of China(No.2020YFB2008600)the financial support from China Scholarship Council(CSC)。
文摘To obtain environmentally friendly,integrated and miniaturized gas sensors for the increasing request for the Internet of Things industry and other relative areas,the ultra-thin CoO_(x)/Zn O heterogeneous film with active interfacial sites was in-situ deposited on micro-electro-mechanical systems(MEMS)as H_(2)S sensor.Atomic layer deposition(ALD)was employed to in-situ fabricate the uniform Zn O thin film.ALD CoO_(x)was deposited on ZnO surface to obtain CoO_(x)/Zn O heterojunction and active interfacial sites.The ultra-thin film(20 nm)with 50 ALD Co O_(x)decorated on 250 ALD Zn O displays excellent sensing performance,including very high response(4.45@200×10^(-9))and selectivity to H_(2)S with a limit of detection(LOD)of 0.38×10^(-9),long-term sensing stability,high response/recovery performance(7.5 s/15.7 s)and mechanical strength at 230。C.Reasons for the high sensing performance of CoO_(x)/Zn O have been confirmed by series of characterizations and density functional theory(DFT)calculation.Heterojunction film thickness with Debye length,the oxygen vacancies and the synergistic effect of active interfacial sites are main reasons for the high sensing performance.The strategy by fabrication of CoO_(x)/Zn O heterogeneous film within Debye length and employing synergistic effect of active interfacial sites offers a promising route for the design of environmentally friendly gas sensors.Furthermore,the ALD technique offers a facile in-situ strategy and high-throughput fabrication of MEMS gas sensors.
文摘The diagnosis of pulmonary hypertension(PH) should be made by combining clinical manifestations and echocardiographic probability.[1] Following the confirmation of PH, the classification should begin with the more common groups [group 2(PH due to left heart disease) and group 3(PH due to lung diseases and/or hypoxia)], then group 4(chronic thromboembolic PH and other pulmonary artery obstructions) and finally group 1(pulmonary arterial hypertension) and group 5(PH with unclear and/or multifactorial mechanisms).[1] In this case, we demonstrate a rare scenario of obstruction-caused group 4 PH.
基金The Parkes Radio Telescope (Murriyang) is part of the Australia Telescope National Facility, which is funded by the Australian Government for operation as a National Facility managed by CSIROsupported by the National Natural Science Foundation of China (NSFC) grant Nos. 12041303, 12041304, 11873067, 12133004, 12203045, 12203070, 12203072, 12103013, U2031117 and T2241020+11 种基金the CAS-MPG LEGACY project and the National SKA Program of China No. 2020SKA0120200the Foundation of Science and Technology of Guizhou Province No. ((2021)023)the Foundation of Guizhou Provincial Education Department (No.KY(2021)303)the National Key Research and Development Program of China Nos. 2022YFC2205202 and 2022YFC2205203the Major Science and Technology Program of Xinjiang Uygur Autonomous Region Nos. 2022A03013-1, 2022A03013-3 and 2022A03013-4the National Key Research and Development Program of China No. 2022YFC2205203the 2021 project Xinjiang Uygur autonomous region of China for Tianshan elites and the Youth Innovation Promotion Association of CAS under No. 2023069support from the Youth Innovation Promotion Association CAS (id. 2021055)CAS Project for Young Scientists in Basic Research (grant YSBR-006)the Cultivation Project for FAST Scientific Payoff and Research Achievement of CAMS-CASsupport from Zhejiang Provincial Natural Science Foundation of China under grant No. LY23A030001supported by the NSF Physics Frontiers Center award number 2020265。
文摘We report the radio observations of the eclipsing black widow pulsar J1720-0534, a 3.26 ms pulsar in orbit with a low mass companion of mass 0.029 to 0.034 M⊙. We obtain the phase-connected timing ephemeris and polarization profile of this millisecond pulsar(MSP) using the Five-hundred-meter Aperture Spherical radio Telescope(FAST), the Green Bank Telescope(GBT), and the Parkes Telescope. For the first time from such a system, an oscillatory polarization angle change was observed from a particular eclipse egress with partial depolarization, indicating 10-milliGauss-level reciprocating magnetic fields oscillating in a length scale of 5 ×10^(3)km(assuming an orbital inclination angle of 90°) outside the companion's magnetosphere. The dispersion measure variation observed during the ingresses and egresses shows the rapid raising of the electron density in the shock boundary between the companion's magnetosphere and the surrounding pulsar wind. We suggest that the observed oscillatory magnetic fields originate from the pulsar wind outside the companion's magnetosphere.
文摘Dear editor,Wellens syndrome is characterized by electrocardiography(ECG)patterns of the biphasic or inverted T wave in the precordial leads with normal R wave progression and absence of Q waves,[1,2]which indicates occlusive lesions of the proximal left anterior descending(LAD)coronary artery and warrants.[1]These ECG changes usually occur during a pain-free interval and turn to a fatal consequence if without urgent intervention therapy.[1,3]However,in some cases,coronary stenosis was absent and ECG patterns manifested as Wellens syndrome,which was defined as pseudo-Wellens syndrome.
基金supported by the University of Michigan-Peking University Health Science Centre(UMHS-PUHSC)Joint Institute for Translational and Clinical Research and the Fundamental Research Funds for the Central Universities(grant numbers:BMU20110177 and BMU20160530)the National Key Research and Development Program of China(grant number:2017YFC1307704)+2 种基金the Scientific Research Seed Fund of Peking University First Hospital(grant numbers:2018SF003 and 2018SF071)Projects of the National Natural Science Foundation of China(grant number:81703288)the Key Laboratory of Molecular Cardiovascular Sciences(Peking University),Ministry of Education and NHC Key Laboratory of Cardiovascular Molecular Biology and Regulatory Peptides。
文摘BACKGROUND Arterial stiffness,as assessed by aortic ultrasound and pulse wave velocity,is associated with incident hypertension.However,there is still no consensus on whether the augmentation index(AI)affects new onset of hypertension.This study investigated the relationship of radial AI(r AI)and incident hypertension in a Chinese community-based population without hypertension at baseline.METHOD A total of 1,615 Chinese non-hypertensive participants from an atherosclerosis cohort in Beijing,China were included in our analysis.Baseline r AI normalized to heart rate of 75 beats/min(r AIp75)was obtained using HEM-9000 AI.New-onset hypertension was defined as blood pressure≥140/90 mm Hg or self-reported hypertension or taking anti-hypertensive medications at the follow up survey.Multivariate regression models were used to evaluate the impact of r AIp75 on the risk of new-onset hypertension.RESULTS After a mean 2.35-year follow-up,213(13.19%)participants developed incident hypertension.No significant relation between r AIp75 and incident hypertension was observed in the whole population after adjustment for possible confounders(adjusted odds ratio(OR)and 95%confidence interval(CI):1.09[0.95-1.27];P=0.2260).However,r AIp75 was significantly associated with incident hypertension in women,but not in men(adjusted OR and 95%CI:1.29[1.06-1.56],P=0.0113 for women;0.91[0.72-1.15],P=0.4244 for men;P for interaction=0.0133).CONCLUSIONS Sex modified the effect of the r AI on incident hypertension in a Chinese,community-based,non-hypertensive population.Screening of the r AI could be considered in women with a high risk of hypertension for the purpose of primary intervention.
