Deep-sea mining activities can potentially release metals,which pose a toxicological threat to deep-sea ecosystems.Nevertheless,due to the remoteness and inaccessibility of the deep-sea biosphere,there is insufficient...Deep-sea mining activities can potentially release metals,which pose a toxicological threat to deep-sea ecosystems.Nevertheless,due to the remoteness and inaccessibility of the deep-sea biosphere,there is insufficient knowledge about the impact of metal exposure on its inhabitants.In this study,deep-sea mussel Gigantidas platifrons,a commonly used deep-sea toxicology model organism,was exposed to manganese(100,1000μg/L)or iron(500,5000μg/L)for 7 d,respectively.Manganese and iron were chosen for their high levels of occurrence within deep-sea deposits.Metal accumulation and a battery of biochemical biomarkers related to antioxidative stress in superoxide dismutase(SOD),catalase(CAT),malondialdehyde(MDA);immune function in alkaline phosphatase(AKP),acid phosphatase(ACP);and energy metabolism in pyruvate kinase(PK)and hexokinase(HK)were assessed in mussel gills.Results showed that deep-sea mussel G.platifrons exhibited a high capacity to accumulate Mn/Fe.In addition,most tested biochemical parameters were altered by metal exposure,demonstrating that metals could induce oxidative stress,suppress the immune system,and affect energy metabolism of deep-sea mussels.The integrated biomarker response(IBR)approach indicated that the exposure to Mn/Fe had a negative impact on deep-sea mussels,and Mn demonstrated a more harmful impact on deep-sea mussels than Fe.Additionally,SOD and CAT biomarkers had the greatest impact on IBR values in Mn treatments,while ACP and HK were most influential for the low-and high-dose Fe groups,respectively.This study represents the first application of the IBR approach to evaluate the toxicity of metals on deep-sea fauna and serves as a crucial framework for risk assessment of deep-sea mining-associated metal exposure.展开更多
Amide-and alkyl-modified nanosilicas(AANPs)were synthesized and introduced into Xanthan gum(XG)solution,aiming to improve the temperature/salt tolerance and oil recovery.The rheological behaviors of XG/AANP hybrid dis...Amide-and alkyl-modified nanosilicas(AANPs)were synthesized and introduced into Xanthan gum(XG)solution,aiming to improve the temperature/salt tolerance and oil recovery.The rheological behaviors of XG/AANP hybrid dispersions were systematically studied at different concentrations,temperatures and inorganic salts.At high temperature(75C)and high salinity(10,000 mg,L1 NaCl),AANPs increase the apparent viscosity and dynamic modulus of the XG solution,and XG/AANP hybrid dispersion exhibits elastic-dominant properties.The most effective concentrations of XG and AANP interacting with each other are 1750 mg·L^(-1) and 0.74 wt%,respectively.The temperature tolerance of XG solution is not satisfactory,and high temperature further weakens the salt tolerance of XG.However,the AANPs significantly enhance the viscoelasticity the XG solution through hydrogen bonds and hydrophobic effect.Under reservoir conditions,XG/AANP hybrid recovers approximately 18.5%more OOIP(original oil in place)than AANP and 11.3%more OOIP than XG.The enhanced oil recovery mechanism of the XG/AANP hybrid is mainly increasing the sweep coefficient,the contribution from the reduction of oil-water interfacial tension is less.展开更多
Mobile edge computing(MEC)provides services to devices and reduces latency in cellular internet of things(IoT)networks.However,the challenging problem is how to deploy MEC servers economically and efficiently.This pap...Mobile edge computing(MEC)provides services to devices and reduces latency in cellular internet of things(IoT)networks.However,the challenging problem is how to deploy MEC servers economically and efficiently.This paper investigates the deployment problem of MEC servers of the real-world road network by employing an improved genetic algorithm(GA)scheme.We first use the threshold-based K-means algorithm to form vehicle clusters according to their locations.We then select base stations(BSs)based on clustering center coordinates as the deployment locations set for potential MEC servers.We further select BSs using a combined simulated annealing(SA)algorithm and GA to minimize the deployment cost.The simulation results show that the improved GA deploys MEC servers effectively.In addition,the proposed algorithm outperforms GA and SA algorithms in terms of convergence speed and solution quality.展开更多
Bimetallic catalysts typically exploit unique synergetic effects between two metal species to achieve their catalytic effect.Understanding the mechanism of CO oxidation using hybrid heterogeneous catalysts is importan...Bimetallic catalysts typically exploit unique synergetic effects between two metal species to achieve their catalytic effect.Understanding the mechanism of CO oxidation using hybrid heterogeneous catalysts is important for effective catalyst design and environmental protection.Herein,we report a Bi-Au/SiO_(2)tandem bimetallic catalyst for the oxidation of CO over the Au/SiO_(2)surface,which was monitored using near-ambient-pressure X-ray photoelectron spectroscopy.The Au-decorated SiO_(2)catalyst exhibited scarce activity in the CO oxidation reaction;however,the introduction of Bi to the Au/SiO_(2)system promoted the catalytic activity.The mechanism is thought to involve the dissociation O_(2)molecules in the presence of Bi,which results in spillover of the O species to adjacent Au atoms,thereby forming Au^(δ+).Further CO adsorption,followed by thermal treatment,facilitated the oxidation of CO at the Au-Bi interface,resulting in a reversible reversion to the neutral Au valence state.Our work provides insight into the mechanism of CO oxidation on tandem surfaces and will facilitate the rational design of other Au-based catalysts.展开更多
Sweetpotato(Ipomoea batatas(L.)Lam.)is a widely grown food crop especially in developing countries.Increasing storage-root yield and dry-matter content has been the main breeding objective of the crop,and DNA marker-a...Sweetpotato(Ipomoea batatas(L.)Lam.)is a widely grown food crop especially in developing countries.Increasing storage-root yield and dry-matter content has been the main breeding objective of the crop,and DNA marker-assisted breeding is needed for this purpose.In this study,using a mapping population of 500 F1 individuals from a cross between Xushu 18(female)and Xu 781(male),we constructed a highdensity genetic linkage map of sweetpotato using 601 simple-sequence repeat(SSR)primer pairs.The Xushu 18 map contained 90 linkage groups with 5547 SSR markers and spanned 18,263.5 cM,and the Xu 781 map contained 90 linkage groups with 4599 SSR markers and spanned 18,043.7 cM,representing the highest genome coverage yet reported for sweetpotato.We identified 33 QTL for storage-root yield and 16 QTL for dry-matter content,explaining respectively 6.5%–47.5%and 3.2%–18.9%of variation.These results provide a foundation for fine-mapping and cloning of QTL and for marker-assisted breeding in sweetpotato.展开更多
The local deformation behavior and dynamic recrystallization of a shock compressed Mg-1Zn alloy was investigated through EBSD and TEM.Since dislocation slipping and twinning were locally suppressed during high strain-...The local deformation behavior and dynamic recrystallization of a shock compressed Mg-1Zn alloy was investigated through EBSD and TEM.Since dislocation slipping and twinning were locally suppressed during high strain-rate deformation,a more flexible kinking deformation was activated to adjusted local orientation and facilitate slipping and twinning within the kinks.Meanwhile,due to the slow heat dissipation that resulted in a local temperature elevating,the kink bands were evolved into deformation bands with recrystallized nano-grains.Such a finding provides a new perspective for kinking-facilitated nanocrystallization in Mg alloys and other anisotropic metallic materials.展开更多
Developing a low-cost and high-efficiency nonprecious metal-based catalyst for hydrogen evolution reaction(HER) is of great significance for the utilization of hydrogen energy.In this work,we report a molecular-modifi...Developing a low-cost and high-efficiency nonprecious metal-based catalyst for hydrogen evolution reaction(HER) is of great significance for the utilization of hydrogen energy.In this work,we report a molecular-modification strategy to fabricate a self-supported hydrogen evolution electrode,specially by grafting the macrocyclic molecules(HHTP=2,3,6,7,10,11-hexahydroxytriphenylene) on the surface of a cobaltous dihydroxy carbonate(COC) seed layer.The HHTP-COC electrode is endowed with a rodlike structure,which provides favorable access for charge transportation and mass exchange.The macrocyclic molecule structure in HHTP can be grafted on COC and improve the electrical conductivity,while the interaction between HHTP and COC induces the rearrangement of charge configuration on the surface.Due to the combination effects of several aspects,the HHTP-COC electrode achieves astonishing HER activity,with a low overpotential of 61.0 mV(η_(10),at the current density of 10 mA cm^(-2)) and excellent stability in alkaline condition.This kind of interface engineering based on the organic molecules can be applied to the design and manufacture of electrocatalysts in the field of energy conversion and storage.展开更多
Carotenoid is a tetraterpene pigment beneficial for human health.Although the carotenoid biosynthesis pathway has been extensively studied in plants,relatively little is known about their regulation in sweet potato.Pr...Carotenoid is a tetraterpene pigment beneficial for human health.Although the carotenoid biosynthesis pathway has been extensively studied in plants,relatively little is known about their regulation in sweet potato.Previously,we conducted the transcriptome database of differentially expressed genes between the sweet potato(Ipomoea batatas)cultivar‘Weiduoli’and its high-carotenoid mutant‘HVB-3’.In this study,we selected one of these candidate genes,IbNAC29,for subsequent analyses.IbNAC29 belongs to the plant-specific NAC(NAM,ATAF1/2,and CUC2)transcription factor family.Relative IbNAC29 mRNA level in the HVB-3 storage roots was∼1.71-fold higher than Weiduoli.Additional experiments showed that the contents ofα-carotene,lutein,β-carotene,zeaxanthin,and capsanthin are obviously increased in the storage roots of transgenic sweet potato plants overexpressing IbNAC29.Moreover,the levels of carotenoid biosynthesis genes in transgenic plants were also up-regulated.Nevertheless,yeast one-hybrid assays indicated that IbNAC29 could not directly bind to the promoters of these carotenoid biosynthesis genes.Furthermore,the level of IbSGR1 was down-regulated,whose homologous genes in tomato can negatively regulate carotene accumulation.Yeast three-hybrid analysis revealed that the IbNAC29-IbMYB1R1-IbAITR5 could form a regulatory module.Yeast one-hybrid,electrophoretic mobility shift assay,quantitative PCR analysis of chromatin immunoprecipitation and dual-luciferase reporter assay showed that IbAITR5 directly binds to and inhibits the promoter activity of IbSGR1,up-regulating carotenoid biosynthesis gene IbPSY.Taken together,IbNAC29 is a potential candidate gene for the genetic improvement of nutritive value in sweet potato.展开更多
Macao Science Satellite-1(known as MSS-1)is a low-inclination mission that will be launched at the beginning of 2023.An optical bench is used for accessing high-precision strength and direction measurements of the mag...Macao Science Satellite-1(known as MSS-1)is a low-inclination mission that will be launched at the beginning of 2023.An optical bench is used for accessing high-precision strength and direction measurements of the magnetic field.In this paper,we present a thermal stability design for the optical bench based on quasi-kinematic support by kinematic hinges on the MSS-1.The change in angles with the finite element method(FEM)model modified by thermal deformation test data is analyzed.The robustness of the structure is also investigated via the Monte Carlo method.Two main results are obtained.First,the peak-to-peak value(Vp-p)of the inter-boresight angle is at most 1.24″,and the Vp-p of the inter-boresight angle modification and analysis is no more than 3.13″,both of which are better than those on the Swarm satellites in orbit.Second,the 90°fibers of the carbon-reinforced arm need to be strictly controlled during the technological process.展开更多
BACKGROUND Patients with thalamic infarction experience abnormal blockages of multinuc-leated vessels,affecting the body and thereby the thalamus.Most patients with thalamic infarction have an adverse prognosis,which ...BACKGROUND Patients with thalamic infarction experience abnormal blockages of multinuc-leated vessels,affecting the body and thereby the thalamus.Most patients with thalamic infarction have an adverse prognosis,which seriously affects their safety.Therefore,it is essential to analyze the independent risk factors that influence the prognosis of patients with thalamic infarction and develop corresponding preventive measures.AIM To explore the effect of non-high-density lipoprotein cholesterol(non-HDL-C)and Homocysteine(Hcy)levels in cognitive impairment in thalamic infarction.METHODS From March 2019 to March 2022,80 patients with thalamic infarction were divided into a group with cognitive impairment[Montreal Cognitive Assessment(MoCA)score<26;35 patients]and a group with normal cognitive function(MoCA score of 26-30;45 patients)according to the MoCA score.In addition,50 healthy people in the same period were selected as the control group.A correlation between the non-HDL-C and Hcy levels and the MoCA score and receiver operating characteristic curve was observed,and the serum non-HDL-C and Hcy levels were analyzed for the diagnosis of cognitive impairment in patients with thalamic infarction.According to the Modified Rankin Scale(MRS)score,80 patients with thalamic infarction were divided into a good prognosis group(MRS score≤2)and a poor prognosis group(MRS score>2).RESULTS The non-HDL-C and Hcy levels were significantly higher in the group with cognitive impairment than in the group with normal cognitive function(P<0.05).There was no significant difference in the non-HDL-C level between the control group and the group with normal cognitive function(P>0.05).The MoCA scores of the group with cognitive impairment were significantly lower than those of the group with normal cognitive function and the control group(P<0.05).There was a significant difference between the control group and the group with normal cognitive function(P<0.05).The non-HDL-C and Hcy levels were correlated with the MoCA score(P<0.05),cognitive impairment[areas under the curve(AUC)=0.709,95%confidence interval(95%CI):0.599-0.816],the non-HDL-C level,and could predict cognitive impairment in patients with thalamic infarction(AUC=0.738,95%CI:0.618-0.859).Hcy combined with non-HDL-C levels can predict cognitive impairment in patients with thalamic infarction(AUC=0.769,95%CI:0.721-0.895).RESULTS There were 50 patients in the good prognosis group and 30 patients in the poor prognosis group.Compared with the good prognosis group,in the poor prognosis group,the National Institutes of Health Stroke Scale(NIHSS)score,non-HDL-C level,Hcy level,large-area cerebral infarction,atrial fibrillation,and activated partial prothrombin time were statistically significant(P<0.05).The non-HDL-C level,the Hcy level,the NIHSS score,extensive cerebral serum,and atrial fibrillation may all be independent risk factors for poor prognosis in patients with thalamic infarction(P<0.05).CONCLUSION Non-HDL-C and Hcy levels are positively correlated with cognitive impairment in patients with thalamic infarction.Non-HDL-C and Hcy levels can be used in the diagnosis of cognitive impairment in patients with thalamic infarction,and the combined detection effect is better.The main factors affecting the prognosis of patients with thalamic infarction are the non-HDL-C level,the Hcy level,the NIHSS score,large-area cerebral infarction,and atrial fibrillation.Clinically,corresponding preventive measures can be formulated based on the above factors to prevent poor prognosis and reduce mortality.展开更多
BACKGROUND Ectopic pancreas may be unfamiliar to many people because it is rare and difficult to diagnose.However,this disease is highly susceptible to misdiagnosis and missed diagnosis.In this article,we report two c...BACKGROUND Ectopic pancreas may be unfamiliar to many people because it is rare and difficult to diagnose.However,this disease is highly susceptible to misdiagnosis and missed diagnosis.In this article,we report two cases of pancreatic heterotopia in the gastric sinus and small intestine,respectively,both of which were confirmed by histopathological examination.CASE SUMMARY The first patient was a 43-year-old female which reported abdominal distension for 2 mo.The second was a 67-year-old female who experienced intermittent epigastric discomfort for 15 d.In both cases,there was no confirmed preoperative examination,and the postoperative pathology indicated the presence of ectopic pancreas.CONCLUSION The diagnosis of ectopic pancreas is difficult,and is often prone to misdiagnosis and the possibility of being overlooked.Various laboratory tests and imaging tests should be carefully evaluated before surgery to achieve early detection,early diagnosis and early treatment.展开更多
BACKGROUND:This study aimed to explore the effects of TNF-a on the expression of IP_3R1mRNA and protein in human mesangial cells(HMCs),and to elucidate the mechanism of TNF-a relating to IP_3R1 expression in the occur...BACKGROUND:This study aimed to explore the effects of TNF-a on the expression of IP_3R1mRNA and protein in human mesangial cells(HMCs),and to elucidate the mechanism of TNF-a relating to IP_3R1 expression in the occurrence of hepatorenal syndrome(HRS).METHODS:HMCs were stimulated by tumor(TNF-a) with 100 ng/mL for different hours(2,4,8,and 24 hours).The expression changes of IP_3R1 mRNA and protein were detected by quantitative real-time polymerase chain reaction and immunoblotting.Several inhibitors including D609,U73122,PP1,safingol,rottlerin and non-radioactive protein kinase C(PKC) were used to examine the mechanism of signal transduction ofTNF-a-regulated IP_3R1 in HMCs.RESULTS:The levels of IP_3R1 mRNA at 2 hours after TNF-a exposure were significantly enhanced and peaked at 8 hours in HMCs(P<0.01),then descended at 24 hours(P<0.01).The levels of IP_3R1 protein at 4 hours after TNF-a exposure were obviously increased and peaked at24 hours after TNF-a exposure(P<0.01).Compared to the control group,safingol(PKCa inhibitor)and D609(phosphatidylcholine-specific phospholipase C inhibitor) significantly blocked the TNF-ainduced expression of IP_3R1 mRNA(3.30±0.81 vs.1.95±0.13,P<0.05;2.10±0.49,P<0.01) and IP_3R1protein(3.09±0.13 vs.1.86+0.39,P<0.01;1.98±0.02,P<0.01).TNF-a promoted PKCa activation with maximal PKCa phosphorylation that occurred 8 hours after stimulation measured by non-radioactive PKC assay,and the effect was markedly attenuated by pretreatment with D609 or safingol.CONCLUSION:TNF-a increased the expression of IP_3R1 and this was mediated,at least in part,through the PC-PLC/PKCa signaling pathways in HMCs.展开更多
基金Supported by the Marine S&T Fund of Shandong Province for Qingdao Marine Science and Technology Center(No.2022QNLM030004-1)the National Natural Science Foundation of China(Nos.42276153,42030407)+2 种基金the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDB42020401)the Key Research Program of Frontier Sciences,CAS(No.ZDBS-LY-DQC032)the National Key R&D Program of China(No.2022YFC2804003)。
文摘Deep-sea mining activities can potentially release metals,which pose a toxicological threat to deep-sea ecosystems.Nevertheless,due to the remoteness and inaccessibility of the deep-sea biosphere,there is insufficient knowledge about the impact of metal exposure on its inhabitants.In this study,deep-sea mussel Gigantidas platifrons,a commonly used deep-sea toxicology model organism,was exposed to manganese(100,1000μg/L)or iron(500,5000μg/L)for 7 d,respectively.Manganese and iron were chosen for their high levels of occurrence within deep-sea deposits.Metal accumulation and a battery of biochemical biomarkers related to antioxidative stress in superoxide dismutase(SOD),catalase(CAT),malondialdehyde(MDA);immune function in alkaline phosphatase(AKP),acid phosphatase(ACP);and energy metabolism in pyruvate kinase(PK)and hexokinase(HK)were assessed in mussel gills.Results showed that deep-sea mussel G.platifrons exhibited a high capacity to accumulate Mn/Fe.In addition,most tested biochemical parameters were altered by metal exposure,demonstrating that metals could induce oxidative stress,suppress the immune system,and affect energy metabolism of deep-sea mussels.The integrated biomarker response(IBR)approach indicated that the exposure to Mn/Fe had a negative impact on deep-sea mussels,and Mn demonstrated a more harmful impact on deep-sea mussels than Fe.Additionally,SOD and CAT biomarkers had the greatest impact on IBR values in Mn treatments,while ACP and HK were most influential for the low-and high-dose Fe groups,respectively.This study represents the first application of the IBR approach to evaluate the toxicity of metals on deep-sea fauna and serves as a crucial framework for risk assessment of deep-sea mining-associated metal exposure.
基金We gratefully acknowledge financial supports from the Major Program of National Natural Science Foundation of China(Grant No.42090024)the National Natural Science Foundation of China(Grant No.52004322)the Natural Science Foundation of Shandong Province,China(Grant No.ZR2020QE108).
文摘Amide-and alkyl-modified nanosilicas(AANPs)were synthesized and introduced into Xanthan gum(XG)solution,aiming to improve the temperature/salt tolerance and oil recovery.The rheological behaviors of XG/AANP hybrid dispersions were systematically studied at different concentrations,temperatures and inorganic salts.At high temperature(75C)and high salinity(10,000 mg,L1 NaCl),AANPs increase the apparent viscosity and dynamic modulus of the XG solution,and XG/AANP hybrid dispersion exhibits elastic-dominant properties.The most effective concentrations of XG and AANP interacting with each other are 1750 mg·L^(-1) and 0.74 wt%,respectively.The temperature tolerance of XG solution is not satisfactory,and high temperature further weakens the salt tolerance of XG.However,the AANPs significantly enhance the viscoelasticity the XG solution through hydrogen bonds and hydrophobic effect.Under reservoir conditions,XG/AANP hybrid recovers approximately 18.5%more OOIP(original oil in place)than AANP and 11.3%more OOIP than XG.The enhanced oil recovery mechanism of the XG/AANP hybrid is mainly increasing the sweep coefficient,the contribution from the reduction of oil-water interfacial tension is less.
基金supported in part by National Key Research and Development Project (2020YFB1807204)in part by the National Natural Science Foundation of China (U2001213 and 61971191)+1 种基金in part by the Beijing Natural Science Foundation under Grant L201011in part by Jiangxi Key Laboratory of Artificial Intelligence Transportation Information Transmission and Processing (20202BCD42010)
文摘Mobile edge computing(MEC)provides services to devices and reduces latency in cellular internet of things(IoT)networks.However,the challenging problem is how to deploy MEC servers economically and efficiently.This paper investigates the deployment problem of MEC servers of the real-world road network by employing an improved genetic algorithm(GA)scheme.We first use the threshold-based K-means algorithm to form vehicle clusters according to their locations.We then select base stations(BSs)based on clustering center coordinates as the deployment locations set for potential MEC servers.We further select BSs using a combined simulated annealing(SA)algorithm and GA to minimize the deployment cost.The simulation results show that the improved GA deploys MEC servers effectively.In addition,the proposed algorithm outperforms GA and SA algorithms in terms of convergence speed and solution quality.
基金the National Natural Science Foundation of China(Nos.11874380 and 22002183)the National Key Research and Development Program of China(No.2021YFA1600800).
文摘Bimetallic catalysts typically exploit unique synergetic effects between two metal species to achieve their catalytic effect.Understanding the mechanism of CO oxidation using hybrid heterogeneous catalysts is important for effective catalyst design and environmental protection.Herein,we report a Bi-Au/SiO_(2)tandem bimetallic catalyst for the oxidation of CO over the Au/SiO_(2)surface,which was monitored using near-ambient-pressure X-ray photoelectron spectroscopy.The Au-decorated SiO_(2)catalyst exhibited scarce activity in the CO oxidation reaction;however,the introduction of Bi to the Au/SiO_(2)system promoted the catalytic activity.The mechanism is thought to involve the dissociation O_(2)molecules in the presence of Bi,which results in spillover of the O species to adjacent Au atoms,thereby forming Au^(δ+).Further CO adsorption,followed by thermal treatment,facilitated the oxidation of CO at the Au-Bi interface,resulting in a reversible reversion to the neutral Au valence state.Our work provides insight into the mechanism of CO oxidation on tandem surfaces and will facilitate the rational design of other Au-based catalysts.
基金supported by the National Key Research and Development Program of China(2019YFD1001300,2019YFD1001301)the Earmarked Fund for CARS-10-Sweetpotato(CARS-10)+1 种基金the Beijing Food Crops Innovation Consortium Program(BAIC02-2022)Hebei Key R&D Program(20326320D,22322911D)。
文摘Sweetpotato(Ipomoea batatas(L.)Lam.)is a widely grown food crop especially in developing countries.Increasing storage-root yield and dry-matter content has been the main breeding objective of the crop,and DNA marker-assisted breeding is needed for this purpose.In this study,using a mapping population of 500 F1 individuals from a cross between Xushu 18(female)and Xu 781(male),we constructed a highdensity genetic linkage map of sweetpotato using 601 simple-sequence repeat(SSR)primer pairs.The Xushu 18 map contained 90 linkage groups with 5547 SSR markers and spanned 18,263.5 cM,and the Xu 781 map contained 90 linkage groups with 4599 SSR markers and spanned 18,043.7 cM,representing the highest genome coverage yet reported for sweetpotato.We identified 33 QTL for storage-root yield and 16 QTL for dry-matter content,explaining respectively 6.5%–47.5%and 3.2%–18.9%of variation.These results provide a foundation for fine-mapping and cloning of QTL and for marker-assisted breeding in sweetpotato.
基金supported by National Natural Science Foundation of China(No.51701121,No.51825101)Shanghai Sailing Program(No.17YF1408800)+2 种基金Laboratory of Intense Dynamic Loading and Effect Foundation of China(No.IDEL1908)Startup Fund for Youngman Research at SJTU(No.18×100040022)Science and Technology Commission of Shanghai Municipality(No.18511109302).
文摘The local deformation behavior and dynamic recrystallization of a shock compressed Mg-1Zn alloy was investigated through EBSD and TEM.Since dislocation slipping and twinning were locally suppressed during high strain-rate deformation,a more flexible kinking deformation was activated to adjusted local orientation and facilitate slipping and twinning within the kinks.Meanwhile,due to the slow heat dissipation that resulted in a local temperature elevating,the kink bands were evolved into deformation bands with recrystallized nano-grains.Such a finding provides a new perspective for kinking-facilitated nanocrystallization in Mg alloys and other anisotropic metallic materials.
基金funded by grants from the National Natural Science Foundation of China (21771101, 52201258)the Natural Science Foundation of Jiangsu Province, China (BK20210651 and BK20210650)the Natural Science Foundation of the Jiangsu Higher Education Institutions of China (21KJB430003)。
文摘Developing a low-cost and high-efficiency nonprecious metal-based catalyst for hydrogen evolution reaction(HER) is of great significance for the utilization of hydrogen energy.In this work,we report a molecular-modification strategy to fabricate a self-supported hydrogen evolution electrode,specially by grafting the macrocyclic molecules(HHTP=2,3,6,7,10,11-hexahydroxytriphenylene) on the surface of a cobaltous dihydroxy carbonate(COC) seed layer.The HHTP-COC electrode is endowed with a rodlike structure,which provides favorable access for charge transportation and mass exchange.The macrocyclic molecule structure in HHTP can be grafted on COC and improve the electrical conductivity,while the interaction between HHTP and COC induces the rearrangement of charge configuration on the surface.Due to the combination effects of several aspects,the HHTP-COC electrode achieves astonishing HER activity,with a low overpotential of 61.0 mV(η_(10),at the current density of 10 mA cm^(-2)) and excellent stability in alkaline condition.This kind of interface engineering based on the organic molecules can be applied to the design and manufacture of electrocatalysts in the field of energy conversion and storage.
基金supported by the National Natural Science Foundation of China(31872878)the earmarked fund for CARS-10-Sweetpotato.
文摘Carotenoid is a tetraterpene pigment beneficial for human health.Although the carotenoid biosynthesis pathway has been extensively studied in plants,relatively little is known about their regulation in sweet potato.Previously,we conducted the transcriptome database of differentially expressed genes between the sweet potato(Ipomoea batatas)cultivar‘Weiduoli’and its high-carotenoid mutant‘HVB-3’.In this study,we selected one of these candidate genes,IbNAC29,for subsequent analyses.IbNAC29 belongs to the plant-specific NAC(NAM,ATAF1/2,and CUC2)transcription factor family.Relative IbNAC29 mRNA level in the HVB-3 storage roots was∼1.71-fold higher than Weiduoli.Additional experiments showed that the contents ofα-carotene,lutein,β-carotene,zeaxanthin,and capsanthin are obviously increased in the storage roots of transgenic sweet potato plants overexpressing IbNAC29.Moreover,the levels of carotenoid biosynthesis genes in transgenic plants were also up-regulated.Nevertheless,yeast one-hybrid assays indicated that IbNAC29 could not directly bind to the promoters of these carotenoid biosynthesis genes.Furthermore,the level of IbSGR1 was down-regulated,whose homologous genes in tomato can negatively regulate carotene accumulation.Yeast three-hybrid analysis revealed that the IbNAC29-IbMYB1R1-IbAITR5 could form a regulatory module.Yeast one-hybrid,electrophoretic mobility shift assay,quantitative PCR analysis of chromatin immunoprecipitation and dual-luciferase reporter assay showed that IbAITR5 directly binds to and inhibits the promoter activity of IbSGR1,up-regulating carotenoid biosynthesis gene IbPSY.Taken together,IbNAC29 is a potential candidate gene for the genetic improvement of nutritive value in sweet potato.
基金funded by the Macao Foundation,the pre-research project of Civil Aerospace Technologies(Nos.D020308 and D020303)which is funded by the China National Space Administrationthe opening fund of the State Key Laboratory of Lunar and Planetary Sciences(Macao University of Science and Technology,Macao FDCT[Science and Technology Development Fund]No.119/2017/A3)。
文摘Macao Science Satellite-1(known as MSS-1)is a low-inclination mission that will be launched at the beginning of 2023.An optical bench is used for accessing high-precision strength and direction measurements of the magnetic field.In this paper,we present a thermal stability design for the optical bench based on quasi-kinematic support by kinematic hinges on the MSS-1.The change in angles with the finite element method(FEM)model modified by thermal deformation test data is analyzed.The robustness of the structure is also investigated via the Monte Carlo method.Two main results are obtained.First,the peak-to-peak value(Vp-p)of the inter-boresight angle is at most 1.24″,and the Vp-p of the inter-boresight angle modification and analysis is no more than 3.13″,both of which are better than those on the Swarm satellites in orbit.Second,the 90°fibers of the carbon-reinforced arm need to be strictly controlled during the technological process.
基金The study was reviewed and approved by the Institutional Review Board of Chaohu Hospital Affiliated to AnhuiMedical University,Approval No.KYXM-202208-011.
文摘BACKGROUND Patients with thalamic infarction experience abnormal blockages of multinuc-leated vessels,affecting the body and thereby the thalamus.Most patients with thalamic infarction have an adverse prognosis,which seriously affects their safety.Therefore,it is essential to analyze the independent risk factors that influence the prognosis of patients with thalamic infarction and develop corresponding preventive measures.AIM To explore the effect of non-high-density lipoprotein cholesterol(non-HDL-C)and Homocysteine(Hcy)levels in cognitive impairment in thalamic infarction.METHODS From March 2019 to March 2022,80 patients with thalamic infarction were divided into a group with cognitive impairment[Montreal Cognitive Assessment(MoCA)score<26;35 patients]and a group with normal cognitive function(MoCA score of 26-30;45 patients)according to the MoCA score.In addition,50 healthy people in the same period were selected as the control group.A correlation between the non-HDL-C and Hcy levels and the MoCA score and receiver operating characteristic curve was observed,and the serum non-HDL-C and Hcy levels were analyzed for the diagnosis of cognitive impairment in patients with thalamic infarction.According to the Modified Rankin Scale(MRS)score,80 patients with thalamic infarction were divided into a good prognosis group(MRS score≤2)and a poor prognosis group(MRS score>2).RESULTS The non-HDL-C and Hcy levels were significantly higher in the group with cognitive impairment than in the group with normal cognitive function(P<0.05).There was no significant difference in the non-HDL-C level between the control group and the group with normal cognitive function(P>0.05).The MoCA scores of the group with cognitive impairment were significantly lower than those of the group with normal cognitive function and the control group(P<0.05).There was a significant difference between the control group and the group with normal cognitive function(P<0.05).The non-HDL-C and Hcy levels were correlated with the MoCA score(P<0.05),cognitive impairment[areas under the curve(AUC)=0.709,95%confidence interval(95%CI):0.599-0.816],the non-HDL-C level,and could predict cognitive impairment in patients with thalamic infarction(AUC=0.738,95%CI:0.618-0.859).Hcy combined with non-HDL-C levels can predict cognitive impairment in patients with thalamic infarction(AUC=0.769,95%CI:0.721-0.895).RESULTS There were 50 patients in the good prognosis group and 30 patients in the poor prognosis group.Compared with the good prognosis group,in the poor prognosis group,the National Institutes of Health Stroke Scale(NIHSS)score,non-HDL-C level,Hcy level,large-area cerebral infarction,atrial fibrillation,and activated partial prothrombin time were statistically significant(P<0.05).The non-HDL-C level,the Hcy level,the NIHSS score,extensive cerebral serum,and atrial fibrillation may all be independent risk factors for poor prognosis in patients with thalamic infarction(P<0.05).CONCLUSION Non-HDL-C and Hcy levels are positively correlated with cognitive impairment in patients with thalamic infarction.Non-HDL-C and Hcy levels can be used in the diagnosis of cognitive impairment in patients with thalamic infarction,and the combined detection effect is better.The main factors affecting the prognosis of patients with thalamic infarction are the non-HDL-C level,the Hcy level,the NIHSS score,large-area cerebral infarction,and atrial fibrillation.Clinically,corresponding preventive measures can be formulated based on the above factors to prevent poor prognosis and reduce mortality.
文摘BACKGROUND Ectopic pancreas may be unfamiliar to many people because it is rare and difficult to diagnose.However,this disease is highly susceptible to misdiagnosis and missed diagnosis.In this article,we report two cases of pancreatic heterotopia in the gastric sinus and small intestine,respectively,both of which were confirmed by histopathological examination.CASE SUMMARY The first patient was a 43-year-old female which reported abdominal distension for 2 mo.The second was a 67-year-old female who experienced intermittent epigastric discomfort for 15 d.In both cases,there was no confirmed preoperative examination,and the postoperative pathology indicated the presence of ectopic pancreas.CONCLUSION The diagnosis of ectopic pancreas is difficult,and is often prone to misdiagnosis and the possibility of being overlooked.Various laboratory tests and imaging tests should be carefully evaluated before surgery to achieve early detection,early diagnosis and early treatment.
基金supported by a grant from Health Bureauof Jiangxi Province
文摘BACKGROUND:This study aimed to explore the effects of TNF-a on the expression of IP_3R1mRNA and protein in human mesangial cells(HMCs),and to elucidate the mechanism of TNF-a relating to IP_3R1 expression in the occurrence of hepatorenal syndrome(HRS).METHODS:HMCs were stimulated by tumor(TNF-a) with 100 ng/mL for different hours(2,4,8,and 24 hours).The expression changes of IP_3R1 mRNA and protein were detected by quantitative real-time polymerase chain reaction and immunoblotting.Several inhibitors including D609,U73122,PP1,safingol,rottlerin and non-radioactive protein kinase C(PKC) were used to examine the mechanism of signal transduction ofTNF-a-regulated IP_3R1 in HMCs.RESULTS:The levels of IP_3R1 mRNA at 2 hours after TNF-a exposure were significantly enhanced and peaked at 8 hours in HMCs(P<0.01),then descended at 24 hours(P<0.01).The levels of IP_3R1 protein at 4 hours after TNF-a exposure were obviously increased and peaked at24 hours after TNF-a exposure(P<0.01).Compared to the control group,safingol(PKCa inhibitor)and D609(phosphatidylcholine-specific phospholipase C inhibitor) significantly blocked the TNF-ainduced expression of IP_3R1 mRNA(3.30±0.81 vs.1.95±0.13,P<0.05;2.10±0.49,P<0.01) and IP_3R1protein(3.09±0.13 vs.1.86+0.39,P<0.01;1.98±0.02,P<0.01).TNF-a promoted PKCa activation with maximal PKCa phosphorylation that occurred 8 hours after stimulation measured by non-radioactive PKC assay,and the effect was markedly attenuated by pretreatment with D609 or safingol.CONCLUSION:TNF-a increased the expression of IP_3R1 and this was mediated,at least in part,through the PC-PLC/PKCa signaling pathways in HMCs.
