Elastic metamaterials with unusual elastic properties offer unprecedented ways to modulate the polarization and propagation of elastic waves.However,most of them rely on the resonant structural components,and thus are...Elastic metamaterials with unusual elastic properties offer unprecedented ways to modulate the polarization and propagation of elastic waves.However,most of them rely on the resonant structural components,and thus are frequency-dependent and unchangeable.Here,we present a reconfigurable 2D mechanism-based metamaterial which possesses transformable and frequency-independent elastic properties.Based on the proposed mechanism-based metamaterial,interesting functionalities,such as ternarycoded elastic wave polarizer and programmable refraction,are demonstrated.Particularly,unique ternary-coded polarizers,with 1-trit polarization filtering and 2-trit polarization separating of longitudinal and transverse waves,are first achieved.Then,the strong anisotropy of the proposed metamaterial is harnessed to realize positive-negative bi-refraction,only-positive refraction,and only-negative refraction.Finally,the wave functions with detailed microstructures are numerically verified.展开更多
In order to improve the energy output consistency of 3, 3’-diamino-4, 4’-azoxyfurazan(DAAF) in the new insensitive booster and the safety and efficiency in the preparation process, a continuous preparation system of...In order to improve the energy output consistency of 3, 3’-diamino-4, 4’-azoxyfurazan(DAAF) in the new insensitive booster and the safety and efficiency in the preparation process, a continuous preparation system of DAAF from synthesis to spherical coating was designed and established in this paper, which combined ultrasonic micromixing reaction with microdroplet globular template. In the rapid micromixing stage, the microfluidic mixing technology with ultrasonic was used to synergistically strengthen the uniform and rapid mass transfer mixing reaction between raw materials to ensure the uniformity of DAAF particle nucleation-growth, and to prepare high-quality DAAF crystals with uniform structure and morphology and concentrated particle size distribution. In the microdroplet globular template stage, the microfluidic droplet technology was used to form a droplet globular template with uniform size under the shear action of the continuous phase of the dispersed phase solution containing DAAF particles and binder. The size of the droplet template was controlled by adjusting the flow rate ratio between the continuous phase and the dispersed phase. In the droplet globular template, with the diffusion of the solvent in the dispersed phase droplets, the binder precipitates to coat the DAAF into a ball, forming a DAAF microsphere with high sphericity, narrow particle size distribution and good monodispersity. The problem of discontinuity and DAAF particle suspension in the process was solved, and the coating theory under this process was studied. DAAF was coated with different binder formulations of fluororubber(F2604), nitrocellulose(NC) and NC/glycidyl azide polymer(GAP), and the process verification and evaluation of the system were carried out. The balling effects of large, medium and small droplet templates under different binder formulations were studied. The scanning electron microscope(SEM) results show that the three droplet templates under the three binder formulations exhibit good balling effect and narrow particle size distribution. The DAAF microspheres were characterized by powder X-ray diffraction(XRD), differential scanning calorimetry(DSC), thermo-gravimetric(TG) and sensitivity analyzer. The results showed that the crystal structure of DAAF did not change during the process, and the prepared DAAF microspheres had lower decomposition temperature and lower mechanical sensitivity than raw DAAF. The results of detonation parameters show that the coating of DAAF by using the above three binder formulations will not greatly reduce the energy output of DAAF, and has comparable detonation performance to raw DAAF. This study proves an efficient and safe continuous system from synthesis to spherical coating modification of explosives, which provides a new way for the continuous, safe and efficient preparation of spherical explosives.展开更多
Lamellar calcite veins are prevalent in carbonate-rich,lacustrine dark shale.The formation mechanisms of these veins have been extensively debated,focusing on factors such as timing,depth,material source,and driving f...Lamellar calcite veins are prevalent in carbonate-rich,lacustrine dark shale.The formation mechanisms of these veins have been extensively debated,focusing on factors such as timing,depth,material source,and driving forces.This paper examines dark lacustrine shale lamellar calcite veins in the Paleogene strata of Dongying Depression,using various analytical techniques:petrography,isotope geochemistry,cathodoluminescence,inclusion thermometry,and electron probe micro-analysis.Two distinct types of calcite veins have been identified:granular calcite veins and sparry calcite veins.These two types differ significantly in color,grain structure,morphology,and inclusions.Through further investigation,it was observed that vein generation occurred from the shallow burial period to the maturation of organic matter,with a transition from granular calcite veins to sparry calcite veins.The granular calcite veins exhibit characteristics associated with the shallow burial period,including plastically deformed laminae and veins,the development of strawberry pyrite,the absence of oil and gas,weak fractionation in oxygen isotopes,and their contact relationship with sparry calcite veins.These granular calcite veins were likely influenced by the reduction of sulfate bacteria.On the other hand,sparry calcite veins with fibrous grains are antitaxial and closely linked to the evolution and maturation of organic matter.They contain oil and gas inclusions and show a distribution range of homogenization temperature between 90℃ and 120℃ and strong fractionation in oxygen isotopes,indicating formation during the hydrocarbon expulsion period.The carbon isotope analysis of the surrounding rocks and veins suggests that the material for vein formation originates from the shale itself,specifically authigenic micritic calcite modified by the action of methanogens.The opening of horizontal fractures and vein formation is likely driven by fluid overpressure resulting from undercompaction and hydrocarbon expulsion.Veins may form rapidly or through multi-stage composite processes.Early veins are predominantly formed in situ,while late veins are a result of continuous fluid migration and convergence.Furthermore,the veins continue to undergo modification even after formation.This study emphasizes that the formation of lamellar calcite veins in shale is a complex diagenetic process influenced by multiple factors:biology,organic matter,and inorganic processes,all operating at various stages throughout the shale's diagenetic history.展开更多
To gain further understanding of the luminescence properties of multiquantum wells and the factors affecting them on a microscopic level,cathodoluminescence combined with scanning transmission electron microscopy and ...To gain further understanding of the luminescence properties of multiquantum wells and the factors affecting them on a microscopic level,cathodoluminescence combined with scanning transmission electron microscopy and spectroscopy was used to measure the luminescence of In_(0.15)Ga_(0.85)N five-period multiquantum wells.The lattice-composition-energy relationship was established with the help of energy-dispersive x-ray spectroscopy,and the bandgaps of In_(0.15)Ga_(0.85)N and GaN in multiple quantum wells were extracted by electron energy loss spectroscopy to understand the features of cathodoluminescence spectra.The luminescence differences between different periods of multiquantum wells and the effects of defects such as composition fluctuation and dislocations on the luminescence of multiple quantum wells were revealed.Our study establishing the direct relationship between the atomic structure of In_(x)Ga_(1-x)N multiquantum wells and photoelectric properties provides useful information for nitride applications.展开更多
1.Objective The West Qinling Orogen extends east-west over 1500 km and is endowed with dozens of large-super large scale gold deposits.The Zaozigou gold deposit has a proven reserve of 134 t with an average grade of 3...1.Objective The West Qinling Orogen extends east-west over 1500 km and is endowed with dozens of large-super large scale gold deposits.The Zaozigou gold deposit has a proven reserve of 134 t with an average grade of 3.08 g/t thus is one of the largest deposits in the West Qinling Orogen.However,whether the fluid type is metamorphic or magmatichydrothermal and ore-formation processes of the Zaozigou gold deposit are equivocal.Scheelite is a ubiquitous accessory mineral in geologically diverse ore-deposit types and attested to be a strong indicator of ore-forming conditions and oredeposit genesis.展开更多
BACKGROUND The prognosis for patients with advanced metastatic cervix cancer(MCC)is poor,and this disease continues to pose a considerable therapeutic challenge.Despite the administration of first-line regimens consis...BACKGROUND The prognosis for patients with advanced metastatic cervix cancer(MCC)is poor,and this disease continues to pose a considerable therapeutic challenge.Despite the administration of first-line regimens consisting of cisplatin,paclitaxel,and bevacizumab,survival rates for patients with metastasis remain poor.The emergence of bispecific antibodies(BsAbs)offers a novel treatment option for patients diagnosed with MCC.CASE SUMMARY In this report,we present a patient with MCC who was treated with cadonilimab monotherapy at a dose of 6 mg/kg every two weeks after chemotherapy was proven to be intolerable.The patient exhibited a sustained complete response for a duration of 6 months,demonstrating an optimistic outlook.CONCLUSION This case illustrates the considerable efficacy of cadonilimab for treating advanced MCC.Therefore,BsAb therapy is a promising strategy for effectively treating patients with advanced MCC and should be considered as an option when patients are intolerant to standard chemotherapy.展开更多
Ferroptosis is one of the critical pathological events in spinal cord injury.Erythropoietin has been reported to improve the recovery of spinal cord injury.However,whether ferroptosis is involved in the neuroprotectiv...Ferroptosis is one of the critical pathological events in spinal cord injury.Erythropoietin has been reported to improve the recovery of spinal cord injury.However,whether ferroptosis is involved in the neuroprotective effects of erythropoietin on spinal cord injury has not been examined.In this study,we established rat models of spinal cord injury by modified Allen’s method and intraperitoneally administered 1000 and 5000 IU/kg erythropoietin once a week for 2 successive weeks.Both low and high doses of erythropoietin promoted recovery of hindlimb function,and the high dose of erythropoietin led to better outcome.High dose of erythropoietin exhibited a stronger suppressive effect on ferroptosis relative to the low dose of erythropoietin.The effects of erythropoietin on inhibiting ferroptosis-related protein expression and restoring mitochondrial morphology were similar to those of Fer-1(a ferroptosis suppressor),and the effects of erythropoietin were largely diminished by RSL3(ferroptosis activator).In vitro experiments showed that erythropoietin inhibited RSL3-induced ferroptosis in PC12 cells and increased the expression of xCT and Gpx4.This suggests that xCT and Gpx4 are involved in the neuroprotective effects of erythropoietin on spinal cord injury.Our findings reveal the underlying anti-ferroptosis role of erythropoietin and provide a potential therapeutic strategy for treating spinal cord injury.展开更多
Polymer bonded explosives(PBXs)have high energy density,excellent mechanical properties and better thermal stability.In this study,droplet microfluidic technology was used to successfully prepare HMX/TATB microspheres...Polymer bonded explosives(PBXs)have high energy density,excellent mechanical properties and better thermal stability.In this study,droplet microfluidic technology was used to successfully prepare HMX/TATB microspheres.The effects of different binder types and binder concentrations on the morphology of the microspheres were studied,and results proved that NC/GAP(1:4)provides particles a regular spherical morphology and good dispersion.Subsequently,the influence of the concentration of the dispersed phase and the flow rate of the continuous phase on the particle size distribution of the microspheres was fully studied.The microspheres had narrow particle size distribution and high spherical shape.Under optimized process conditions,HMX/TATB microspheres were prepared and compared with the physical mixtures.The X-ray diffraction,differential scanning calorimetry,flow properties,bulk density,and mechanical sensitivity of the samples were also studied.Results showed that the crystal form of the microspheres remains unchanged,and the binder maintains good compatibility with explosives.In addition,the fluidity,bulk density,real density and safety performance of the microspheres are remarkably better than the physical mixture.This study provides a new method for preparing PBX with narrow particle size distribution,high spherical shape,excellent dispersion and high bulk density.展开更多
BACKGROUND At present,the incidence rate of ischemic stroke in young people is increasing yearly,and the age of onset is increasingly young.Therefore,primary and secondary prevention of ischemic stroke in young people...BACKGROUND At present,the incidence rate of ischemic stroke in young people is increasing yearly,and the age of onset is increasingly young.Therefore,primary and secondary prevention of ischemic stroke in young people,especially secondary prevention,is particularly crucial.AIM We aimed to comprehensively evaluate risk factors for stroke recurrence in firstever young ischemic stroke(YIS)patients.METHODS The meta-analysis was used to quantitatively analyze the research results on risk factors for stroke recurrence in first-ever YIS patients both domestically and internationally.Stata12.0 software was used for heterogeneity testing,publication bias analysis,sensitivity analysis,and the calculation of combined odds ratios and 95%confidence intervals.RESULTS The odds ratio(OR)values of the relationship between hypertension and hyperlipidemia and recurrence of first-ever YIS were 1.54(1.05-2.26)and 1.12(1.00-1.25),respectively.The OR values of male sex,type 2 diabetes,smoking,drinking and YIS recurrence were 1.66(0.98-2.79),1.01(0.64-1.59),1.21(0.83-1.76),and 1.28(0.82-2.53),respectively.The relationship between male sex,type 2 diabetes,smoking,drinking and YIS recurrence was ambiguous.CONCLUSION Hypertension and hyperlipidemia are important risk factors for stroke recurrence in first-ever YIS patients,and active intervention should be taken.展开更多
BACKGROUND The incidence rate of cerebral infarction in young people is increasing day by day,the age of onset tends to be younger,and its internal pathogenesis and mechanism are very complicated,which leads to greate...BACKGROUND The incidence rate of cerebral infarction in young people is increasing day by day,the age of onset tends to be younger,and its internal pathogenesis and mechanism are very complicated,which leads to greater difficulties in treatment.Therefore,it is essential to analyze the key pathway that affects the onset of cerebral infarction in young people from the perspective of genetics.AIM To compare the differentially expressed genes in the brain tissue of young and aged rats with middle cerebral artery occlusion and to analyse their effect on the key signalling pathway involved in the development of cerebral ischaemia in young rats.METHODS The Gene Expression Omnibus 2R online analysis tool was used to analyse the differentially expressed genes in the GSE166162 dataset regarding the development of cerebral ischaemia in young and aged groups of rats.DAVID 6.8 software was further used to filter the differentially expressed genes.These genes were subjected to Gene Ontology(GO)function analysis and Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway enrichment analysis to determine the key gene pathway that affects the occurrence of cerebral ischaemia in young rats.RESULTS Thirty-five differentially expressed genes(such as Igf2,Col1a2,and Sfrp1)were obtained;73 GO enrichment analysis pathways are mainly involved in biological processes such as drug response,amino acid stimulation response,blood vessel development,various signalling pathways,and enzyme regulation.They are involved in molecular functions such as drug binding,protein binding,dopamine binding,metal ion binding,and dopamine neurotransmitter receptor activity.KEGG pathway enrichment analysis showed a significantly enriched pathway:The cyclic adenosine monophosphate(c-AMP)signalling pathway.CONCLUSION The c-AMP signalling pathway might be the key pathway in the intervention of cerebral infarction in young people.展开更多
In this paper, the NU308 bearing rings were subjected to strengthen grinding treatment (SGT) at ambient temperature. And the running reliabilities of specimens that subjected to SGT and conventional treatment (CT) wer...In this paper, the NU308 bearing rings were subjected to strengthen grinding treatment (SGT) at ambient temperature. And the running reliabilities of specimens that subjected to SGT and conventional treatment (CT) were respectively investigated by testing dynamic properties including the running temperature, vibrations, and surface burning. Moreover, the residual stress, microtopography, and microstructures on the cross-section were respectively tested with residual stress analyzer and field-emission scanning electron microscopy. The results showed that the running reliabilities of the specimen after SGT had been significantly improved with the reduction of running temperature, vibration, and surface burning. Further study showed that the specimen’s surface was filled with disordered micropores after SGT compared to the regular strip texture on the CT specimen’s surface, and the maximum residual compressive stress induced by SGT was about −900 MPa. Moreover, the thickness of the residual compressive stress layer was over 180 µm, while the thickness of severe plastic deformation layer was about 50 µm.展开更多
<strong>Background:</strong> The outbreak of COVID-19 has a significant impact on the health of people around the world. In the clinical condition of COVID-19, the condition of critical cases changes rapid...<strong>Background:</strong> The outbreak of COVID-19 has a significant impact on the health of people around the world. In the clinical condition of COVID-19, the condition of critical cases changes rapidly with a high mortality rate. Therefore, early prediction of disease severity and active intervention play an important role in the prognosis of severe patients. <strong>Methods:</strong> All the patients with COVID-19 in Taizhou city were retrospectively included and segregated into the non-severe and severe group according to the severity of the disease. The clinical manifestations, laboratory examination results, and imaging findings of the 2 groups were analyzed for comparing the differences between the 2 groups. Univariate and multivariate logistic regression were used for screening the factors that could predict the disease, and the nomogram was constructed.<strong> Results:</strong> A total of 143 laboratory-confirmed cases were included in the study, including 110 non-severe patients and 33 severe patients. The median age of patients was 47 years (range, 4 - 86 years). Fever (73.4%) and cough (63.6%) were the most common initial clinical symptoms. By using the method of multivariate logistic regression, the variables to construct nomogram include age (OR: 1.052, 95% CI: 1.020 - 1.086, <em>P </em>= 0.001), body temperature (OR: 2.252, 95% CI: 1.139 - 4.450, <em>P</em> = 0.020), lymphocyte count (OR: 1.128, 95% CI: 1.000 - 1.272, <em>P </em>= 0.049), ADA (OR: 1.163, 95% CI: 1.023 - 1.323, <em>P </em>= 0.021), PaO<sub>2</sub> (OR: 0.972, 95% CI: 0.953 - 0.992, P = 0.007), IL-10 (OR: 1.184, 95% CI: 1.037 - 1.351, <em>P</em> = 0.012), and bronchiectasis (OR: 3.818, 95% CI: 1.694 - 8.605, <em>P</em> = 0.001). The AUC of the established nomogram was 0.877. <strong>Conclusions: </strong>This study analyzed the cases of patients with COVID-19 in Taizhou city and constructed a model to predict the illness severity. When patients showed the features including older age, high body temperature, low lymphocyte count, low ADA value, low PaO<sub>2</sub>, high IL-10, and bronchiectasis sign in CT predicts a greater likelihood of severe COVID-19.展开更多
The hydrological processes of mountainous watersheds in inland river basins are complicated.It is absolutely significant to quantify mountainous runoff for social,economic and ecological purposes.This paper takes the ...The hydrological processes of mountainous watersheds in inland river basins are complicated.It is absolutely significant to quantify mountainous runoff for social,economic and ecological purposes.This paper takes the mountainous watershed of the Heihe Mainstream River as a study area to simulate the hydrological processes of mountainous watersheds in inland river basins by using the soil and water assessment tool(SWAT)model.SWAT simulation results show that both the Nash–Sutcliffe efficiency and the determination coefficient values of the calibration period(January 1995 to December 2002)and validation period(January 2002 to December 2009)are higher than 0.90,and the percent bias is controlled within±5%,indicating that the simulation results are satisfactory.According to the SWAT performance,we discussed the yearly and monthly variation trends of the mountainous runoff and the runoff components.The results show that from 1996 to 2009,an indistinctive rising trend was observed for the yearly mountainous runoff,which is mainly recharged by lateral flow,and followed by shallow groundwater runoff and surface runoff.The monthly variation demonstrates that the mountainous runoff decreases slightly from May to July,contrary to other months.The mountainous runoff is mainly recharged by shallow groundwater runoff in January,February,and from October to December,by surface runoff in March and April,and by lateral flow from May to September.展开更多
基金supported by the National Key R&D Program of China(No.2021YFE0110900)the National Natural Science Foundation of China(Nos.U22B2078 and 11991033)。
文摘Elastic metamaterials with unusual elastic properties offer unprecedented ways to modulate the polarization and propagation of elastic waves.However,most of them rely on the resonant structural components,and thus are frequency-dependent and unchangeable.Here,we present a reconfigurable 2D mechanism-based metamaterial which possesses transformable and frequency-independent elastic properties.Based on the proposed mechanism-based metamaterial,interesting functionalities,such as ternarycoded elastic wave polarizer and programmable refraction,are demonstrated.Particularly,unique ternary-coded polarizers,with 1-trit polarization filtering and 2-trit polarization separating of longitudinal and transverse waves,are first achieved.Then,the strong anisotropy of the proposed metamaterial is harnessed to realize positive-negative bi-refraction,only-positive refraction,and only-negative refraction.Finally,the wave functions with detailed microstructures are numerically verified.
基金National Natural Science Foundation of China(Grant No.22005275)to provide fund for conducting experiments.
文摘In order to improve the energy output consistency of 3, 3’-diamino-4, 4’-azoxyfurazan(DAAF) in the new insensitive booster and the safety and efficiency in the preparation process, a continuous preparation system of DAAF from synthesis to spherical coating was designed and established in this paper, which combined ultrasonic micromixing reaction with microdroplet globular template. In the rapid micromixing stage, the microfluidic mixing technology with ultrasonic was used to synergistically strengthen the uniform and rapid mass transfer mixing reaction between raw materials to ensure the uniformity of DAAF particle nucleation-growth, and to prepare high-quality DAAF crystals with uniform structure and morphology and concentrated particle size distribution. In the microdroplet globular template stage, the microfluidic droplet technology was used to form a droplet globular template with uniform size under the shear action of the continuous phase of the dispersed phase solution containing DAAF particles and binder. The size of the droplet template was controlled by adjusting the flow rate ratio between the continuous phase and the dispersed phase. In the droplet globular template, with the diffusion of the solvent in the dispersed phase droplets, the binder precipitates to coat the DAAF into a ball, forming a DAAF microsphere with high sphericity, narrow particle size distribution and good monodispersity. The problem of discontinuity and DAAF particle suspension in the process was solved, and the coating theory under this process was studied. DAAF was coated with different binder formulations of fluororubber(F2604), nitrocellulose(NC) and NC/glycidyl azide polymer(GAP), and the process verification and evaluation of the system were carried out. The balling effects of large, medium and small droplet templates under different binder formulations were studied. The scanning electron microscope(SEM) results show that the three droplet templates under the three binder formulations exhibit good balling effect and narrow particle size distribution. The DAAF microspheres were characterized by powder X-ray diffraction(XRD), differential scanning calorimetry(DSC), thermo-gravimetric(TG) and sensitivity analyzer. The results showed that the crystal structure of DAAF did not change during the process, and the prepared DAAF microspheres had lower decomposition temperature and lower mechanical sensitivity than raw DAAF. The results of detonation parameters show that the coating of DAAF by using the above three binder formulations will not greatly reduce the energy output of DAAF, and has comparable detonation performance to raw DAAF. This study proves an efficient and safe continuous system from synthesis to spherical coating modification of explosives, which provides a new way for the continuous, safe and efficient preparation of spherical explosives.
基金the support of the National Natural Science Foundation of China(project number:41572123)。
文摘Lamellar calcite veins are prevalent in carbonate-rich,lacustrine dark shale.The formation mechanisms of these veins have been extensively debated,focusing on factors such as timing,depth,material source,and driving forces.This paper examines dark lacustrine shale lamellar calcite veins in the Paleogene strata of Dongying Depression,using various analytical techniques:petrography,isotope geochemistry,cathodoluminescence,inclusion thermometry,and electron probe micro-analysis.Two distinct types of calcite veins have been identified:granular calcite veins and sparry calcite veins.These two types differ significantly in color,grain structure,morphology,and inclusions.Through further investigation,it was observed that vein generation occurred from the shallow burial period to the maturation of organic matter,with a transition from granular calcite veins to sparry calcite veins.The granular calcite veins exhibit characteristics associated with the shallow burial period,including plastically deformed laminae and veins,the development of strawberry pyrite,the absence of oil and gas,weak fractionation in oxygen isotopes,and their contact relationship with sparry calcite veins.These granular calcite veins were likely influenced by the reduction of sulfate bacteria.On the other hand,sparry calcite veins with fibrous grains are antitaxial and closely linked to the evolution and maturation of organic matter.They contain oil and gas inclusions and show a distribution range of homogenization temperature between 90℃ and 120℃ and strong fractionation in oxygen isotopes,indicating formation during the hydrocarbon expulsion period.The carbon isotope analysis of the surrounding rocks and veins suggests that the material for vein formation originates from the shale itself,specifically authigenic micritic calcite modified by the action of methanogens.The opening of horizontal fractures and vein formation is likely driven by fluid overpressure resulting from undercompaction and hydrocarbon expulsion.Veins may form rapidly or through multi-stage composite processes.Early veins are predominantly formed in situ,while late veins are a result of continuous fluid migration and convergence.Furthermore,the veins continue to undergo modification even after formation.This study emphasizes that the formation of lamellar calcite veins in shale is a complex diagenetic process influenced by multiple factors:biology,organic matter,and inorganic processes,all operating at various stages throughout the shale's diagenetic history.
基金Project supported by the National Key R&D Program of China (Grant No. 2019YFA0708202)the National Natural Science Foundation of China (Grant Nos. 11974023, 52021006, 61974139, 12074369, and 12104017)+1 种基金the “2011 Program” from the Peking–Tsinghua–IOP Collaborative Innovation Center of Quantum Matterthe Youth Supporting Program of Institute of Semiconductors
文摘To gain further understanding of the luminescence properties of multiquantum wells and the factors affecting them on a microscopic level,cathodoluminescence combined with scanning transmission electron microscopy and spectroscopy was used to measure the luminescence of In_(0.15)Ga_(0.85)N five-period multiquantum wells.The lattice-composition-energy relationship was established with the help of energy-dispersive x-ray spectroscopy,and the bandgaps of In_(0.15)Ga_(0.85)N and GaN in multiple quantum wells were extracted by electron energy loss spectroscopy to understand the features of cathodoluminescence spectra.The luminescence differences between different periods of multiquantum wells and the effects of defects such as composition fluctuation and dislocations on the luminescence of multiple quantum wells were revealed.Our study establishing the direct relationship between the atomic structure of In_(x)Ga_(1-x)N multiquantum wells and photoelectric properties provides useful information for nitride applications.
基金supported by Records of China’s Mineral Geology from the China Geological Survey(DD20190379)the State Key Program of National Natural Science Foundation of China(41730426)the 111 Project of the Ministry of Science and Technology(BP0719021)。
文摘1.Objective The West Qinling Orogen extends east-west over 1500 km and is endowed with dozens of large-super large scale gold deposits.The Zaozigou gold deposit has a proven reserve of 134 t with an average grade of 3.08 g/t thus is one of the largest deposits in the West Qinling Orogen.However,whether the fluid type is metamorphic or magmatichydrothermal and ore-formation processes of the Zaozigou gold deposit are equivocal.Scheelite is a ubiquitous accessory mineral in geologically diverse ore-deposit types and attested to be a strong indicator of ore-forming conditions and oredeposit genesis.
文摘BACKGROUND The prognosis for patients with advanced metastatic cervix cancer(MCC)is poor,and this disease continues to pose a considerable therapeutic challenge.Despite the administration of first-line regimens consisting of cisplatin,paclitaxel,and bevacizumab,survival rates for patients with metastasis remain poor.The emergence of bispecific antibodies(BsAbs)offers a novel treatment option for patients diagnosed with MCC.CASE SUMMARY In this report,we present a patient with MCC who was treated with cadonilimab monotherapy at a dose of 6 mg/kg every two weeks after chemotherapy was proven to be intolerable.The patient exhibited a sustained complete response for a duration of 6 months,demonstrating an optimistic outlook.CONCLUSION This case illustrates the considerable efficacy of cadonilimab for treating advanced MCC.Therefore,BsAb therapy is a promising strategy for effectively treating patients with advanced MCC and should be considered as an option when patients are intolerant to standard chemotherapy.
基金supported by the National Natural Science Foundation of China,Nos.81871785 and 81672161(both to ZSY)。
文摘Ferroptosis is one of the critical pathological events in spinal cord injury.Erythropoietin has been reported to improve the recovery of spinal cord injury.However,whether ferroptosis is involved in the neuroprotective effects of erythropoietin on spinal cord injury has not been examined.In this study,we established rat models of spinal cord injury by modified Allen’s method and intraperitoneally administered 1000 and 5000 IU/kg erythropoietin once a week for 2 successive weeks.Both low and high doses of erythropoietin promoted recovery of hindlimb function,and the high dose of erythropoietin led to better outcome.High dose of erythropoietin exhibited a stronger suppressive effect on ferroptosis relative to the low dose of erythropoietin.The effects of erythropoietin on inhibiting ferroptosis-related protein expression and restoring mitochondrial morphology were similar to those of Fer-1(a ferroptosis suppressor),and the effects of erythropoietin were largely diminished by RSL3(ferroptosis activator).In vitro experiments showed that erythropoietin inhibited RSL3-induced ferroptosis in PC12 cells and increased the expression of xCT and Gpx4.This suggests that xCT and Gpx4 are involved in the neuroprotective effects of erythropoietin on spinal cord injury.Our findings reveal the underlying anti-ferroptosis role of erythropoietin and provide a potential therapeutic strategy for treating spinal cord injury.
基金supported by the National Natural Science Foundation of China(No.22005275)Scientific and Technological Innovation Programs of Higher Education Institutions in Shanxi(STIP,No.2019L0584)the Advantage Disciplines Climbing Plan of Shanxi Province.
文摘Polymer bonded explosives(PBXs)have high energy density,excellent mechanical properties and better thermal stability.In this study,droplet microfluidic technology was used to successfully prepare HMX/TATB microspheres.The effects of different binder types and binder concentrations on the morphology of the microspheres were studied,and results proved that NC/GAP(1:4)provides particles a regular spherical morphology and good dispersion.Subsequently,the influence of the concentration of the dispersed phase and the flow rate of the continuous phase on the particle size distribution of the microspheres was fully studied.The microspheres had narrow particle size distribution and high spherical shape.Under optimized process conditions,HMX/TATB microspheres were prepared and compared with the physical mixtures.The X-ray diffraction,differential scanning calorimetry,flow properties,bulk density,and mechanical sensitivity of the samples were also studied.Results showed that the crystal form of the microspheres remains unchanged,and the binder maintains good compatibility with explosives.In addition,the fluidity,bulk density,real density and safety performance of the microspheres are remarkably better than the physical mixture.This study provides a new method for preparing PBX with narrow particle size distribution,high spherical shape,excellent dispersion and high bulk density.
基金The Key Research Project of The Third People's Hospital of Hefei,No.SYKZ202301.
文摘BACKGROUND At present,the incidence rate of ischemic stroke in young people is increasing yearly,and the age of onset is increasingly young.Therefore,primary and secondary prevention of ischemic stroke in young people,especially secondary prevention,is particularly crucial.AIM We aimed to comprehensively evaluate risk factors for stroke recurrence in firstever young ischemic stroke(YIS)patients.METHODS The meta-analysis was used to quantitatively analyze the research results on risk factors for stroke recurrence in first-ever YIS patients both domestically and internationally.Stata12.0 software was used for heterogeneity testing,publication bias analysis,sensitivity analysis,and the calculation of combined odds ratios and 95%confidence intervals.RESULTS The odds ratio(OR)values of the relationship between hypertension and hyperlipidemia and recurrence of first-ever YIS were 1.54(1.05-2.26)and 1.12(1.00-1.25),respectively.The OR values of male sex,type 2 diabetes,smoking,drinking and YIS recurrence were 1.66(0.98-2.79),1.01(0.64-1.59),1.21(0.83-1.76),and 1.28(0.82-2.53),respectively.The relationship between male sex,type 2 diabetes,smoking,drinking and YIS recurrence was ambiguous.CONCLUSION Hypertension and hyperlipidemia are important risk factors for stroke recurrence in first-ever YIS patients,and active intervention should be taken.
文摘BACKGROUND The incidence rate of cerebral infarction in young people is increasing day by day,the age of onset tends to be younger,and its internal pathogenesis and mechanism are very complicated,which leads to greater difficulties in treatment.Therefore,it is essential to analyze the key pathway that affects the onset of cerebral infarction in young people from the perspective of genetics.AIM To compare the differentially expressed genes in the brain tissue of young and aged rats with middle cerebral artery occlusion and to analyse their effect on the key signalling pathway involved in the development of cerebral ischaemia in young rats.METHODS The Gene Expression Omnibus 2R online analysis tool was used to analyse the differentially expressed genes in the GSE166162 dataset regarding the development of cerebral ischaemia in young and aged groups of rats.DAVID 6.8 software was further used to filter the differentially expressed genes.These genes were subjected to Gene Ontology(GO)function analysis and Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway enrichment analysis to determine the key gene pathway that affects the occurrence of cerebral ischaemia in young rats.RESULTS Thirty-five differentially expressed genes(such as Igf2,Col1a2,and Sfrp1)were obtained;73 GO enrichment analysis pathways are mainly involved in biological processes such as drug response,amino acid stimulation response,blood vessel development,various signalling pathways,and enzyme regulation.They are involved in molecular functions such as drug binding,protein binding,dopamine binding,metal ion binding,and dopamine neurotransmitter receptor activity.KEGG pathway enrichment analysis showed a significantly enriched pathway:The cyclic adenosine monophosphate(c-AMP)signalling pathway.CONCLUSION The c-AMP signalling pathway might be the key pathway in the intervention of cerebral infarction in young people.
文摘In this paper, the NU308 bearing rings were subjected to strengthen grinding treatment (SGT) at ambient temperature. And the running reliabilities of specimens that subjected to SGT and conventional treatment (CT) were respectively investigated by testing dynamic properties including the running temperature, vibrations, and surface burning. Moreover, the residual stress, microtopography, and microstructures on the cross-section were respectively tested with residual stress analyzer and field-emission scanning electron microscopy. The results showed that the running reliabilities of the specimen after SGT had been significantly improved with the reduction of running temperature, vibration, and surface burning. Further study showed that the specimen’s surface was filled with disordered micropores after SGT compared to the regular strip texture on the CT specimen’s surface, and the maximum residual compressive stress induced by SGT was about −900 MPa. Moreover, the thickness of the residual compressive stress layer was over 180 µm, while the thickness of severe plastic deformation layer was about 50 µm.
文摘<strong>Background:</strong> The outbreak of COVID-19 has a significant impact on the health of people around the world. In the clinical condition of COVID-19, the condition of critical cases changes rapidly with a high mortality rate. Therefore, early prediction of disease severity and active intervention play an important role in the prognosis of severe patients. <strong>Methods:</strong> All the patients with COVID-19 in Taizhou city were retrospectively included and segregated into the non-severe and severe group according to the severity of the disease. The clinical manifestations, laboratory examination results, and imaging findings of the 2 groups were analyzed for comparing the differences between the 2 groups. Univariate and multivariate logistic regression were used for screening the factors that could predict the disease, and the nomogram was constructed.<strong> Results:</strong> A total of 143 laboratory-confirmed cases were included in the study, including 110 non-severe patients and 33 severe patients. The median age of patients was 47 years (range, 4 - 86 years). Fever (73.4%) and cough (63.6%) were the most common initial clinical symptoms. By using the method of multivariate logistic regression, the variables to construct nomogram include age (OR: 1.052, 95% CI: 1.020 - 1.086, <em>P </em>= 0.001), body temperature (OR: 2.252, 95% CI: 1.139 - 4.450, <em>P</em> = 0.020), lymphocyte count (OR: 1.128, 95% CI: 1.000 - 1.272, <em>P </em>= 0.049), ADA (OR: 1.163, 95% CI: 1.023 - 1.323, <em>P </em>= 0.021), PaO<sub>2</sub> (OR: 0.972, 95% CI: 0.953 - 0.992, P = 0.007), IL-10 (OR: 1.184, 95% CI: 1.037 - 1.351, <em>P</em> = 0.012), and bronchiectasis (OR: 3.818, 95% CI: 1.694 - 8.605, <em>P</em> = 0.001). The AUC of the established nomogram was 0.877. <strong>Conclusions: </strong>This study analyzed the cases of patients with COVID-19 in Taizhou city and constructed a model to predict the illness severity. When patients showed the features including older age, high body temperature, low lymphocyte count, low ADA value, low PaO<sub>2</sub>, high IL-10, and bronchiectasis sign in CT predicts a greater likelihood of severe COVID-19.
基金supported by the National Natural Science Foundation of China(41240002,91125025,91225302,Y211121001)the National Science and Technology Support Projects(2011BAC07B05)
文摘The hydrological processes of mountainous watersheds in inland river basins are complicated.It is absolutely significant to quantify mountainous runoff for social,economic and ecological purposes.This paper takes the mountainous watershed of the Heihe Mainstream River as a study area to simulate the hydrological processes of mountainous watersheds in inland river basins by using the soil and water assessment tool(SWAT)model.SWAT simulation results show that both the Nash–Sutcliffe efficiency and the determination coefficient values of the calibration period(January 1995 to December 2002)and validation period(January 2002 to December 2009)are higher than 0.90,and the percent bias is controlled within±5%,indicating that the simulation results are satisfactory.According to the SWAT performance,we discussed the yearly and monthly variation trends of the mountainous runoff and the runoff components.The results show that from 1996 to 2009,an indistinctive rising trend was observed for the yearly mountainous runoff,which is mainly recharged by lateral flow,and followed by shallow groundwater runoff and surface runoff.The monthly variation demonstrates that the mountainous runoff decreases slightly from May to July,contrary to other months.The mountainous runoff is mainly recharged by shallow groundwater runoff in January,February,and from October to December,by surface runoff in March and April,and by lateral flow from May to September.
