Mesoscale eddies play a central role in the poleward oceanic heat flux in the Southern Ocean.Previous studies have documented changes in the location of temperature fronts in the Southern Ocean,but little attention ha...Mesoscale eddies play a central role in the poleward oceanic heat flux in the Southern Ocean.Previous studies have documented changes in the location of temperature fronts in the Southern Ocean,but little attention has been paid to changes in the genesis locations of mesoscale eddies.Here,we provide evidence from three decades of satellite altimetry observations for the heterogeneity of the poleward shift of mesoscale activities,with the largest trend of~0.23°±0.05°(10 yr)^(-1) over the Atlantic sector and a moderate trend of~0.1°±0.03°(10 yr)^(-1) over the Indian sector,but no significant trend in the Pacific sector.The poleward shift of mesoscale eddies is associated with a southward shift of the local westerly winds while being constrained by the major topographies.As the poleward shift of westerly winds is projected to persist,the poleward oceanic heat flux from mesoscale eddies may influence future ice melt.展开更多
Cesium tungsten bronze （CsxW03） powders were synthesized by hydrothermal reaction at 190 ℃ by using sodium tungstate and cesium carbonate as raw materials, and the effects of N2 annealing on the microstructure and ...Cesium tungsten bronze （CsxW03） powders were synthesized by hydrothermal reaction at 190 ℃ by using sodium tungstate and cesium carbonate as raw materials, and the effects of N2 annealing on the microstructure and near-infrared （NIR） shielding as well as heat insulation properties of CsxW03 were investigated. The results indicated that the synthesized CsxW03 powders exhibited hexagohal CSo.32WO3 crystal structure, and subsequent N2 annealing could further improve the crystallinity of CsxW03 particles. Moreover, the NIR shielding and heat insulation properties of CsxW03 could be further improved after N2 annealing at appropriate temperature for a period of time. Particularly, the 500 ℃-annealed CsxW03 products in the N2 atmosphere showed the best NIR shielding and heat insulation properties. When the N2 annealing temperature was higher than 700 ℃, the NIR shielding properties decreased again. The 800 ℃-annealed samples in the N2 atmosphere showed higher visible light transmittance, however, the NIR shielding properties were lower than that of the non-annealed samples.展开更多
In random network models, sizes for pores and throats are distributed according to a truncated Weibull distribution. As a result, parameters defining the shape of the distribution are critical for the characteristic o...In random network models, sizes for pores and throats are distributed according to a truncated Weibull distribution. As a result, parameters defining the shape of the distribution are critical for the characteristic of the network. In this paper, an algorithm to distribute pores and throats in random network was established to more representatively describe the topology of porous media. First, relations between Weibull parameters and the distribution of dimensionless throat sizes were studied and a series of standard curves were obtained. Then, by analyzing the capillary pressure curve of the core sample, frequency distribution histogram of throat sizes was obtained. All the sizes were transformed to dimensionless numbers ranged from 0 to 1. Curves of the core were compared to the standard curves, and truncated Weibull parameters could be determined according an inverse algorithm. Finally, aspect ratio and average length of throats were adjusted to simultaneously fit the porosity and the capillary pressure curves and the whole network was established. The predicted relative permeability curves were in good agreement with the experimental data of cores, indicating the validity of the algorithm.展开更多
Electroacupuncture preconditioning at acupoint Baihui （GV20） can reduce focal cerebral ischemia/reperfusion injury. However, the precise protective mechanism remains unknown. Mitochondrial fission mediated by dynami...Electroacupuncture preconditioning at acupoint Baihui （GV20） can reduce focal cerebral ischemia/reperfusion injury. However, the precise protective mechanism remains unknown. Mitochondrial fission mediated by dynamin-related protein 1 （Drp1） can trigger neuronal apoptosis following cerebral ischemia/reperfusion injury. Herein, we examined the hypothesis that electroacupuncture pretreatment can regulate Drp1, and thus inhibit mitochondrial fission to provide cerebral protection. Rat models of focal cerebral ischemia/reperfusion injury were established by middle cerebral artery occlusion at 24 hours after 5 consecutive days of preconditioning with electroacupuncture at GV20 （depth 2 mm, intensity 1 mA, frequency 2/15 Hz, for 30 minutes, once a day）. Neurological function was assessed using the Longa neurological deficit score. Pathological changes in the ischemic penumbra on the injury side were assessed by hematoxylin-eosin staining. Cellular apoptosis in the ischemic penumbra on the injury side was assessed by terminal deoxyribonucleotidyl transferase-mediated dUTP-digoxigenin nick end labeling staining. Mitochondrial ultrastructure in the ischemic penumbra on the injury side was assessed by transmission electron microscopy. Drp1 and cytochrome c expression in the ischemic penumbra on the injury side were assessed by western blot assay. Results showed that electroacupuncture preconditioning decreased expression of total and mitochondrial Drp1, decreased expression of total and cytosolic cytochrome c, maintained mitochondrial morphology and reduced the proportion of apoptotic cells in the ischemic penumbra on the injury side, with associated improvements in neurological function. These data suggest that electroacupuncture preconditioning-induced neuronal protection involves inhibition of the expression and translocation of Drp1.展开更多
Selective brain hypothermia is considered an effective treatment for neuronal injury after stroke,and avoids the complications of general hypothermia.However,the mechanisms by which selective brain hypothermia affects...Selective brain hypothermia is considered an effective treatment for neuronal injury after stroke,and avoids the complications of general hypothermia.However,the mechanisms by which selective brain hypothermia affects mitochondrial fission remain unknown.In this study,we investigated the effect of selective brain hypothermia on the expression of fission 1 (Fis1) protein,a key factor in the mitochondrial fission system,during focal cerebral ischemia/reperfusion injury.Sprague-Dawley rats were divided into four groups.In the sham group,the carotid arteries were exposed only.In the other three groups,middle cerebral artery occlusion was performed using the intraluminal filament technique.After 2 hours of occlusion,the filament was slowly removed to allow blood reperfusion in the ischemia/reperfusion group.Saline,at 4℃ and 37℃,were perfused through the carotid artery in the hypothermia and normothermia groups,respectively,followed by restoration of blood flow.Neurological function was assessed with the Zea Longa 5-point scoring method.Cerebral infarct volume was assessed by 2,3,5-triphenyltetrazolium chloride staining,and apoptosis was assessed by terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling staining.Fis1 and cytosolic cytochrome c levels were assessed by western blot assay.Fis1 mRNA expression was assessed by quantitative reverse transcription-polymerase chain reaction.Mitochondrial ultrastructure was evaluated by transmission electron microscopy.Compared with the sham group,apoptosis,Fis1 protein and mRNA expression and cytosolic cytochrome c levels in the cortical ischemic penumbra and cerebral infarct volume were increased after reperfusion in the other three groups.These changes caused by cerebral ischemia/reperfusion were inhibited in the hypothermia group compared with the normothermia group.These findings show that selective brain hypothermia inhibits Fis1 expression and reduces apoptosis,thereby ameliorating focal cerebral ischemia/reperfusion injury in rats.Experiments were authorized by the Ethics Committee of Qingdao Municipal Hospital of China (approval No.2019008).展开更多
The present study established a model of brain ischemia in aged rats using four-vessel occlusion.We observed hippocampal CA1 neuronal apoptosis and apoptosis-mediated protease caspase-3 expression following preconditi...The present study established a model of brain ischemia in aged rats using four-vessel occlusion.We observed hippocampal CA1 neuronal apoptosis and apoptosis-mediated protease caspase-3 expression following preconditioning of electroacupuncture at Baihui（GV 20）.Our results showed that the number of hippocampal CA1 normal neurons was decreased,and degenerated neurons were increased 12 hours to 3 days following cerebral ischemia/reperfusion.The number of hippocampal CA1 apoptotic neurons and caspase-3-positive neurons in rats with cerebral ischemia/reperfusion injury was significantly decreased following acupuncture preconditioning.Acupuncture preconditioning protects aged rats against ischemia/reperfusion injury by regulating caspase-3 protein expression.展开更多
Silica aerogels were prepared at ambient drying by using ethanol/trimethylchlorosilane （TMCS）/heptane solution as pore water exchange and surface modification of the wet gel before drying. The obtained silica aeroge...Silica aerogels were prepared at ambient drying by using ethanol/trimethylchlorosilane （TMCS）/heptane solution as pore water exchange and surface modification of the wet gel before drying. The obtained silica aerogels exhibit a sponge-like structure with uniform pore size distribution. The effects of heat-treatment on the hydrophobicity, specific surface area and other properties were investigated. The results indicated that the hydrophobicity of silica aerogels could be maintained up to 350℃. With increasing heating temperature, hydrophobicity decreased, and became completely hydrophilic after heat-treatment at 500℃. Brunaueremmitt-teller （BET） surface area results indicated that the specific surface area of silica aerogels increased with increasing heating temperature in the range of 150-500℃. The effects of heat-treatment on the morphology and chemical bonding state of silica aerogels were investigated by scanning electron microscopy （SEM）, differential temperature analysis （DTA） and Fourier-transform infrared spectroscopy （FT-IR）.展开更多
Electroacupuncture has therapeutic effects on ischemic brain injury, but its mechanism is still poorly understood. In this study, mice were stimulated by electroacupuncture at the Baihui（GV20） acupoint for 30 minute...Electroacupuncture has therapeutic effects on ischemic brain injury, but its mechanism is still poorly understood. In this study, mice were stimulated by electroacupuncture at the Baihui（GV20） acupoint for 30 minutes at 1 m A and 2/15 Hz for 5 consecutive days. A cerebral ischemia model was established by ligating the bilateral common carotid artery for 15 minutes. At 72 hours after injury, neuronal injury in the mouse hippocampus had lessened, and the number of terminal deoxynucleotide transferase-mediated d UTP nick-end labeling-positive cells reduced after electroacupuncture treatment. Moreover, expression of adenosine monophosphate-activated protein kinase α（AMPKα） and phosphorylated AMPKα was up-regulated. Intraperitoneal injection of the AMPK antagonist, compound C, suppressed this phenomenon. Our findings suggest that electroacupuncture preconditioning alleviates ischemic brain injury via AMPK activation.展开更多
BACKGROUND Vascular complications of transradial percutaneous coronary intervention(PCI)are rare and usually occur at the access site below the elbow.Life-threatening vascular complications during transradial PCI ther...BACKGROUND Vascular complications of transradial percutaneous coronary intervention(PCI)are rare and usually occur at the access site below the elbow.Life-threatening vascular complications during transradial PCI therapy,such as vessel perforation and dissection in the brachiocephalic,subclavian,internal mammary,and thyrocervical arteries,are rarely reported.Subclavian artery bleeding is a potentially serious complication of vascular interventional procedures leading to tracheal obstruction,hemothorax,respiratory failure,hemorrhagic shock,and death if not diagnosed early and treated promptly.CASE SUMMARY A male patient with typical angina pectoris underwent coronary angiography and stent implantation.During the procedure,the patient felt pharyngeal pain and tightness,which we mistook for myocardial ischemia.After PCI,swelling in the right neck and supraclavicular area was observed.The patient experienced dyspnea,emergency endotracheal intubation was performed,and then a sudden drop in blood pressure was observed.Ultrasound and contrast-enhanced computed tomography scans demonstrated a cervical hematoma severely compressing the trachea due to subclavian artery bleeding.Brachiocephalic angiography revealed a vascular injury site at the root of the right subclavian artery at the intersection of the right common carotid artery.A covered stent was deployed to the right subclavian artery with successful sealing of the perforation,and a bare stent was implanted in the junction of the right common carotid and brachiocephalic arteries to prevent obstruction of blood flow to the brain.CONCLUSION Subclavian artery bleeding is a lifethreatening complication of PCI.Early prevention,rapid recognition,and prompt treatment may improve the prognosis.展开更多
In this work, a kind of preparation method of zwitterionic ion chromatography （ZIC） stationary phase modified with phosphorylcholine （PC） was obtained by hydrolyzing after bonding phosphorylcholine dichloride to d...In this work, a kind of preparation method of zwitterionic ion chromatography （ZIC） stationary phase modified with phosphorylcholine （PC） was obtained by hydrolyzing after bonding phosphorylcholine dichloride to diol-silica to better explore the characteristics of the PC groups as ZIC stationary phase ligand in simultaneous separation of acidic proteins and basic proteins. The results showed that tv^o kinds of acidic proteins and three kinds of basic proteins can be separated completely, meanwhile, hen egg white was separated and purified and three kinds of egg white components ovalbumin, G2 ovoglobulin and ovotransfemin proteins were separated completely by one single step on PC-ZIC column, the purity of all proteins reached above 95%. PC-ZIC stationary phase was successfully improved with better separation capacity and selectivity than previously reported in this paper.展开更多
[Objectives]To explore the relationship between neutrophil percentage to albumin ratio(NPAR),monocyte to high density lipoprotein ratio(MHR),fasting blood glucose(GLU)and CAD+T2DM and its diagnostic value.[Methods]A t...[Objectives]To explore the relationship between neutrophil percentage to albumin ratio(NPAR),monocyte to high density lipoprotein ratio(MHR),fasting blood glucose(GLU)and CAD+T2DM and its diagnostic value.[Methods]A total of 3937 patients who underwent coronary angiography in the Affiliated Hospital of Chengde Medical University from January 2016 to December 2018 were collected.The patients with Gensini score>0 and diabetes were selected as the experimental group(CAD+T2DM,n=756),and the patients with Gensini score=0 and without diabetes were taken as the control group(n=388),with a total of 1144 cases.The patient's medical record number,sex,age,contact number,biochemical test results,cardiac color ultrasound,coronary artery imaging and other data were recorded.NPAR,MHR,and GLU were calculated.A binary Logistic regression model was established combined with the receiver operating characteristic(ROC)curve.The predictive value of single index and joint test for CAD+T2DM was analyzed.[Results]The serum levels of NPAR,MHR and GLU in CAD+T2DM were significantly higher than those in the control group.Binary Logistic regression analysis showed that serum NPAR,MHR and GLU were risk factors for CAD+T2DM(P<0.05).The final prediction model is P=1/[1+e-(-3.722+0.014×NPAR+0.51×MHR+0.461×GLU)].ROC curve showed that the area under the curve of serum NPAR,MHR and GLU was 0.739,0.628 and 0.852,respectively,and the prediction probability of combined detection was 0.882,which was significantly higher than that of single index.[Conclusions]There was a close correlation between serum NPAR,MHR,GLU and CAD+T2DM in patients with coronary heart disease.The combined application of these indexes can significantly improve the predictive value of CAD+T2DM.展开更多
An injection-seeded single-frequency Q-switched Nd：YAG laser is accomplished by using a phase modulated rampfire technique. A RbTiOPO4（RTP） electro-optic crystal is selected for effective optical path length modula...An injection-seeded single-frequency Q-switched Nd：YAG laser is accomplished by using a phase modulated rampfire technique. A RbTiOPO4（RTP） electro-optic crystal is selected for effective optical path length modulation of the slave self-filtering unstable resonator. This single-frequency laser is capable of producing 50 m J pulse energy at 1 Hz repetition rate with a pulse width of 16 ns. The standard deviation of laser pulse intensity for consecutive 100 shots from the mean pulse intensity is less than 1.05%. A spectral linewidth of less than 0.5 pm with a frequency jitter of about 14 fm over30 min is obtained.展开更多
BACKGROUND Pheochromocytoma is a rare catecholamines-secreting tumor arising from chromaffin cells in the adrenal medulla.It classically presents with paroxysmal hypertension,headaches,palpitations,sweating,and metabo...BACKGROUND Pheochromocytoma is a rare catecholamines-secreting tumor arising from chromaffin cells in the adrenal medulla.It classically presents with paroxysmal hypertension,headaches,palpitations,sweating,and metabolic disorders.Atypical presentations such as acute myocardial infarction,heart failure,cardiomyopathy,stroke,and transient erythrocytosis have been infrequently documented.CASE SUMMARY We describe the case of a 72-year-old man diagnosed with pheochromocytoma presenting with non-ST segment elevation myocardial infarction,heart failure,and transient erythrocytosis with nonobstructed coronary arteries.This was his second heart attack.The patient was previously diagnosed with myocardial infarction,and an immense mass was found on the left adrenal gland 3 years prior.Based on clinical and laboratory findings,a diagnosis of pheochromocytoma was confirmed.His coronary angiogram showed nonobstructed coronary arteries except for a myocardial bridge in the left anterior descending branch.This was a form of type-2 myocardial infarction.The myocardial cell lesions were caused by sudden secretion of catecholamines by the pheochromocytoma.Even more atypically,his hemoglobin level was obviously elevated at admission,but after a few days of treatment with an alpha-adrenergic receptor blocker,it dropped to normal levels without additional treatment.CONCLUSION Pheochromocytoma may be a cause of acute myocardial infarction,heart failure,and transient erythrocytosis.展开更多
The aim of this paper is to solve the problems that the existing method of critical production of gas cap reservoir is only suitable for single-phase flow, and the method of critical production of gas cap reservoir un...The aim of this paper is to solve the problems that the existing method of critical production of gas cap reservoir is only suitable for single-phase flow, and the method of critical production of gas cap reservoir under water-flooding is still blank. In this paper, the relationships between dynamic and static equilibrium, plane radial flow theory, oil-water infiltration method and three-dimensional seepage field decomposition theory, were applied to study a calculation method for critical production of directional wells and horizontal wells. Furthermore, the effects of different factors on critical output were studied, such as horizontal permeability, ratio of horizontal permeability to vertical permeability, length of horizontal section, effective thickness, viscosity of crude oil and water content etc. Results show that the critical production increases with the increment of the horizontal permeability, the ratio of the vertical permeability to the horizontal permeability, the reservoir thickness and the horizontal well length;when the viscosity of crude oil is small, the critical production decreases first and then increases with the increase of water content;when the viscosity of crude oil is high, the critical production increases continuously with the increase of water content. This study could provide theoretical and technical guidance for changing of the working system of oil wells. It can avoid gas channeling and improve the development effect.展开更多
Sepsis,a life-threatening condition triggered by a dysregulated host response to infection,remains a major challenge for therapeutic intervention.Despite the growing interest in immunomodulatory strategies for sepsis ...Sepsis,a life-threatening condition triggered by a dysregulated host response to infection,remains a major challenge for therapeutic intervention.Despite the growing interest in immunomodulatory strategies for sepsis treatment,the effects and mechanisms of these approaches on the organ-specific inflammatory and immunosuppressive states induced by sepsis are poorly understood.According to existing studies,capsaicin(CPS)has pharmacological effects such as analgesic,antipruritic,hypolipidemia,hypoglycemia,anti-inflammatory and antibacterial,and antitumor activity.1 However,the effectiveness of CPs in treating sepsis is still unknown.展开更多
Architecturat heritage conservation is an important field in architectural research. The Hui-styte vernacutar dwetling is an essentialarchitectural heritage of China. Its hollow watt system, with horsehead-like upper ...Architecturat heritage conservation is an important field in architectural research. The Hui-styte vernacutar dwetling is an essentialarchitectural heritage of China. Its hollow watt system, with horsehead-like upper corners, is a distinct architecturat feature that is worth preserving. However, the thermat performance of the hollow watt is relatively poor by today＇s standard. The current study developed a novel approach, whereby foam concrete was used to fill the voids inside the holtow watt to improve its thermat resistance. This approach was deemed cost effective, easy to learn, and capable of preserving the architectural integrity of the watt. Different types of foam concrete were prepared and tested. Testing results showed that the material properties of foam concrete are suitabte for thermaUy upgrading the hollow watt system. Ctimate chamber testing was conducted to investigate the effectiveness of the proposed thermat upgrading strategy. The testing resutts suggested that tilting the voids with foam concrete can effectively improve the overall thermal resistance of the holtow watt system by 24%, which is almost equal to the overall thermal resistance when using the more expensive commercial inorganic stucco system.展开更多
Detailed survey and inspection of the structure of the lecture hall of the Anyuan Miners’Club were conducted during a restoration project.Nondestructive inspection measures were used to assess the physical and mechan...Detailed survey and inspection of the structure of the lecture hall of the Anyuan Miners’Club were conducted during a restoration project.Nondestructive inspection measures were used to assess the physical and mechanical conditions of the structure.The brick and wood structures of the building were tested,the overall bearing capacity was calculated,and a safety appraisal was conducted in accordance with the codes and standards of the existing building.Inspection results provide architects and construction engineers with reliable data to develop a preservation plan and ensure the safety of the heritage building.展开更多
In this paper, an approach to optimize set points is proposed for controlled Organic Rankine Cycle(ORC)systems. Owing to both disturbances and variations of operating point existing in ORC systems, it is necessary to ...In this paper, an approach to optimize set points is proposed for controlled Organic Rankine Cycle(ORC)systems. Owing to both disturbances and variations of operating point existing in ORC systems, it is necessary to optimize the set points for controlled ORC systems so as to improve the energy conversion efficiency. At first, the optimal set points of controlled ORC systems are investigated by revisiting performance analysis and optimization of ORC systems. The expected set points of the evaporating pressure and the temperature at evaporator outlet are then determined by combining genetic algorithm with least squares support vector machine(GA-LSSVM). Simulation results show that the predicted results by GA-LSSVM can be regarded as the optimal set points of controlled ORC systems with varying operating conditions.展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.42230405,42006029)Science and Technology Plan of Liaoning Province(2024JH2/102400061)+1 种基金Dalian Science and Technology Innovation Fund(2024JJ11PT007)Dalian Science and Technology Pro-gram for Innovation Talents of Dalian(2022RJ06).
文摘Mesoscale eddies play a central role in the poleward oceanic heat flux in the Southern Ocean.Previous studies have documented changes in the location of temperature fronts in the Southern Ocean,but little attention has been paid to changes in the genesis locations of mesoscale eddies.Here,we provide evidence from three decades of satellite altimetry observations for the heterogeneity of the poleward shift of mesoscale activities,with the largest trend of~0.23°±0.05°(10 yr)^(-1) over the Atlantic sector and a moderate trend of~0.1°±0.03°(10 yr)^(-1) over the Indian sector,but no significant trend in the Pacific sector.The poleward shift of mesoscale eddies is associated with a southward shift of the local westerly winds while being constrained by the major topographies.As the poleward shift of westerly winds is projected to persist,the poleward oceanic heat flux from mesoscale eddies may influence future ice melt.
基金financially supported by the National Natural Science Foundation of China(No.51278074)the Project Sponsored by the Scientific Research Foundation for the Returned Overseas Chinese Scholars,State Education Ministry(the[42nd,20111139])
文摘Cesium tungsten bronze （CsxW03） powders were synthesized by hydrothermal reaction at 190 ℃ by using sodium tungstate and cesium carbonate as raw materials, and the effects of N2 annealing on the microstructure and near-infrared （NIR） shielding as well as heat insulation properties of CsxW03 were investigated. The results indicated that the synthesized CsxW03 powders exhibited hexagohal CSo.32WO3 crystal structure, and subsequent N2 annealing could further improve the crystallinity of CsxW03 particles. Moreover, the NIR shielding and heat insulation properties of CsxW03 could be further improved after N2 annealing at appropriate temperature for a period of time. Particularly, the 500 ℃-annealed CsxW03 products in the N2 atmosphere showed the best NIR shielding and heat insulation properties. When the N2 annealing temperature was higher than 700 ℃, the NIR shielding properties decreased again. The 800 ℃-annealed samples in the N2 atmosphere showed higher visible light transmittance, however, the NIR shielding properties were lower than that of the non-annealed samples.
文摘In random network models, sizes for pores and throats are distributed according to a truncated Weibull distribution. As a result, parameters defining the shape of the distribution are critical for the characteristic of the network. In this paper, an algorithm to distribute pores and throats in random network was established to more representatively describe the topology of porous media. First, relations between Weibull parameters and the distribution of dimensionless throat sizes were studied and a series of standard curves were obtained. Then, by analyzing the capillary pressure curve of the core sample, frequency distribution histogram of throat sizes was obtained. All the sizes were transformed to dimensionless numbers ranged from 0 to 1. Curves of the core were compared to the standard curves, and truncated Weibull parameters could be determined according an inverse algorithm. Finally, aspect ratio and average length of throats were adjusted to simultaneously fit the porosity and the capillary pressure curves and the whole network was established. The predicted relative permeability curves were in good agreement with the experimental data of cores, indicating the validity of the algorithm.
基金supported by the Natural Science Foundation of Shandong Province of China,No.ZR2015HM023a grant from the Science and Technology Plan Project of Shinan District of Qingdao City of China,No.2016-3-029-YY
文摘Electroacupuncture preconditioning at acupoint Baihui （GV20） can reduce focal cerebral ischemia/reperfusion injury. However, the precise protective mechanism remains unknown. Mitochondrial fission mediated by dynamin-related protein 1 （Drp1） can trigger neuronal apoptosis following cerebral ischemia/reperfusion injury. Herein, we examined the hypothesis that electroacupuncture pretreatment can regulate Drp1, and thus inhibit mitochondrial fission to provide cerebral protection. Rat models of focal cerebral ischemia/reperfusion injury were established by middle cerebral artery occlusion at 24 hours after 5 consecutive days of preconditioning with electroacupuncture at GV20 （depth 2 mm, intensity 1 mA, frequency 2/15 Hz, for 30 minutes, once a day）. Neurological function was assessed using the Longa neurological deficit score. Pathological changes in the ischemic penumbra on the injury side were assessed by hematoxylin-eosin staining. Cellular apoptosis in the ischemic penumbra on the injury side was assessed by terminal deoxyribonucleotidyl transferase-mediated dUTP-digoxigenin nick end labeling staining. Mitochondrial ultrastructure in the ischemic penumbra on the injury side was assessed by transmission electron microscopy. Drp1 and cytochrome c expression in the ischemic penumbra on the injury side were assessed by western blot assay. Results showed that electroacupuncture preconditioning decreased expression of total and mitochondrial Drp1, decreased expression of total and cytosolic cytochrome c, maintained mitochondrial morphology and reduced the proportion of apoptotic cells in the ischemic penumbra on the injury side, with associated improvements in neurological function. These data suggest that electroacupuncture preconditioning-induced neuronal protection involves inhibition of the expression and translocation of Drp1.
基金supported by the Natural Science Foundation of Shandong Province of China,No.ZR2015HM023(to MSW)the Science and Technology Plan Project of Qingdao City of China,No.19-6-1-50-nsh(to MSW)
文摘Selective brain hypothermia is considered an effective treatment for neuronal injury after stroke,and avoids the complications of general hypothermia.However,the mechanisms by which selective brain hypothermia affects mitochondrial fission remain unknown.In this study,we investigated the effect of selective brain hypothermia on the expression of fission 1 (Fis1) protein,a key factor in the mitochondrial fission system,during focal cerebral ischemia/reperfusion injury.Sprague-Dawley rats were divided into four groups.In the sham group,the carotid arteries were exposed only.In the other three groups,middle cerebral artery occlusion was performed using the intraluminal filament technique.After 2 hours of occlusion,the filament was slowly removed to allow blood reperfusion in the ischemia/reperfusion group.Saline,at 4℃ and 37℃,were perfused through the carotid artery in the hypothermia and normothermia groups,respectively,followed by restoration of blood flow.Neurological function was assessed with the Zea Longa 5-point scoring method.Cerebral infarct volume was assessed by 2,3,5-triphenyltetrazolium chloride staining,and apoptosis was assessed by terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling staining.Fis1 and cytosolic cytochrome c levels were assessed by western blot assay.Fis1 mRNA expression was assessed by quantitative reverse transcription-polymerase chain reaction.Mitochondrial ultrastructure was evaluated by transmission electron microscopy.Compared with the sham group,apoptosis,Fis1 protein and mRNA expression and cytosolic cytochrome c levels in the cortical ischemic penumbra and cerebral infarct volume were increased after reperfusion in the other three groups.These changes caused by cerebral ischemia/reperfusion were inhibited in the hypothermia group compared with the normothermia group.These findings show that selective brain hypothermia inhibits Fis1 expression and reduces apoptosis,thereby ameliorating focal cerebral ischemia/reperfusion injury in rats.Experiments were authorized by the Ethics Committee of Qingdao Municipal Hospital of China (approval No.2019008).
基金the Science and Technology Bureau of South District of Qingdao, No. 2008041
文摘The present study established a model of brain ischemia in aged rats using four-vessel occlusion.We observed hippocampal CA1 neuronal apoptosis and apoptosis-mediated protease caspase-3 expression following preconditioning of electroacupuncture at Baihui（GV 20）.Our results showed that the number of hippocampal CA1 normal neurons was decreased,and degenerated neurons were increased 12 hours to 3 days following cerebral ischemia/reperfusion.The number of hippocampal CA1 apoptotic neurons and caspase-3-positive neurons in rats with cerebral ischemia/reperfusion injury was significantly decreased following acupuncture preconditioning.Acupuncture preconditioning protects aged rats against ischemia/reperfusion injury by regulating caspase-3 protein expression.
文摘Silica aerogels were prepared at ambient drying by using ethanol/trimethylchlorosilane （TMCS）/heptane solution as pore water exchange and surface modification of the wet gel before drying. The obtained silica aerogels exhibit a sponge-like structure with uniform pore size distribution. The effects of heat-treatment on the hydrophobicity, specific surface area and other properties were investigated. The results indicated that the hydrophobicity of silica aerogels could be maintained up to 350℃. With increasing heating temperature, hydrophobicity decreased, and became completely hydrophilic after heat-treatment at 500℃. Brunaueremmitt-teller （BET） surface area results indicated that the specific surface area of silica aerogels increased with increasing heating temperature in the range of 150-500℃. The effects of heat-treatment on the morphology and chemical bonding state of silica aerogels were investigated by scanning electron microscopy （SEM）, differential temperature analysis （DTA） and Fourier-transform infrared spectroscopy （FT-IR）.
基金supported by the National Natural Science Foundation of China,No.81273821
文摘Electroacupuncture has therapeutic effects on ischemic brain injury, but its mechanism is still poorly understood. In this study, mice were stimulated by electroacupuncture at the Baihui（GV20） acupoint for 30 minutes at 1 m A and 2/15 Hz for 5 consecutive days. A cerebral ischemia model was established by ligating the bilateral common carotid artery for 15 minutes. At 72 hours after injury, neuronal injury in the mouse hippocampus had lessened, and the number of terminal deoxynucleotide transferase-mediated d UTP nick-end labeling-positive cells reduced after electroacupuncture treatment. Moreover, expression of adenosine monophosphate-activated protein kinase α（AMPKα） and phosphorylated AMPKα was up-regulated. Intraperitoneal injection of the AMPK antagonist, compound C, suppressed this phenomenon. Our findings suggest that electroacupuncture preconditioning alleviates ischemic brain injury via AMPK activation.
基金Supported by Scientific Research Program of Hebei Administration of Traditional Chinese Medicine,China,No.2021201Science and Technology Support Plan Project of Chengde,China,No.201701A072.
文摘BACKGROUND Vascular complications of transradial percutaneous coronary intervention(PCI)are rare and usually occur at the access site below the elbow.Life-threatening vascular complications during transradial PCI therapy,such as vessel perforation and dissection in the brachiocephalic,subclavian,internal mammary,and thyrocervical arteries,are rarely reported.Subclavian artery bleeding is a potentially serious complication of vascular interventional procedures leading to tracheal obstruction,hemothorax,respiratory failure,hemorrhagic shock,and death if not diagnosed early and treated promptly.CASE SUMMARY A male patient with typical angina pectoris underwent coronary angiography and stent implantation.During the procedure,the patient felt pharyngeal pain and tightness,which we mistook for myocardial ischemia.After PCI,swelling in the right neck and supraclavicular area was observed.The patient experienced dyspnea,emergency endotracheal intubation was performed,and then a sudden drop in blood pressure was observed.Ultrasound and contrast-enhanced computed tomography scans demonstrated a cervical hematoma severely compressing the trachea due to subclavian artery bleeding.Brachiocephalic angiography revealed a vascular injury site at the root of the right subclavian artery at the intersection of the right common carotid artery.A covered stent was deployed to the right subclavian artery with successful sealing of the perforation,and a bare stent was implanted in the junction of the right common carotid and brachiocephalic arteries to prevent obstruction of blood flow to the brain.CONCLUSION Subclavian artery bleeding is a lifethreatening complication of PCI.Early prevention,rapid recognition,and prompt treatment may improve the prognosis.
基金supported by the National Natural Science Foundation(No.21006077)the foundation of science and technology in Shaanxi Province(No.2010K12-01-05)the foundation for construction of key disciplines of analytical chemistry in Shaanxi Province
文摘In this work, a kind of preparation method of zwitterionic ion chromatography （ZIC） stationary phase modified with phosphorylcholine （PC） was obtained by hydrolyzing after bonding phosphorylcholine dichloride to diol-silica to better explore the characteristics of the PC groups as ZIC stationary phase ligand in simultaneous separation of acidic proteins and basic proteins. The results showed that tv^o kinds of acidic proteins and three kinds of basic proteins can be separated completely, meanwhile, hen egg white was separated and purified and three kinds of egg white components ovalbumin, G2 ovoglobulin and ovotransfemin proteins were separated completely by one single step on PC-ZIC column, the purity of all proteins reached above 95%. PC-ZIC stationary phase was successfully improved with better separation capacity and selectivity than previously reported in this paper.
基金Key Medical Science Research Project of Hebei Health and Family Planning Commission(20181153).
文摘[Objectives]To explore the relationship between neutrophil percentage to albumin ratio(NPAR),monocyte to high density lipoprotein ratio(MHR),fasting blood glucose(GLU)and CAD+T2DM and its diagnostic value.[Methods]A total of 3937 patients who underwent coronary angiography in the Affiliated Hospital of Chengde Medical University from January 2016 to December 2018 were collected.The patients with Gensini score>0 and diabetes were selected as the experimental group(CAD+T2DM,n=756),and the patients with Gensini score=0 and without diabetes were taken as the control group(n=388),with a total of 1144 cases.The patient's medical record number,sex,age,contact number,biochemical test results,cardiac color ultrasound,coronary artery imaging and other data were recorded.NPAR,MHR,and GLU were calculated.A binary Logistic regression model was established combined with the receiver operating characteristic(ROC)curve.The predictive value of single index and joint test for CAD+T2DM was analyzed.[Results]The serum levels of NPAR,MHR and GLU in CAD+T2DM were significantly higher than those in the control group.Binary Logistic regression analysis showed that serum NPAR,MHR and GLU were risk factors for CAD+T2DM(P<0.05).The final prediction model is P=1/[1+e-(-3.722+0.014×NPAR+0.51×MHR+0.461×GLU)].ROC curve showed that the area under the curve of serum NPAR,MHR and GLU was 0.739,0.628 and 0.852,respectively,and the prediction probability of combined detection was 0.882,which was significantly higher than that of single index.[Conclusions]There was a close correlation between serum NPAR,MHR,GLU and CAD+T2DM in patients with coronary heart disease.The combined application of these indexes can significantly improve the predictive value of CAD+T2DM.
基金Project supported by the National Key Research and Development Program of China(Grant Nos.2017YFB1104500 and 2016YFB0701000)
文摘An injection-seeded single-frequency Q-switched Nd：YAG laser is accomplished by using a phase modulated rampfire technique. A RbTiOPO4（RTP） electro-optic crystal is selected for effective optical path length modulation of the slave self-filtering unstable resonator. This single-frequency laser is capable of producing 50 m J pulse energy at 1 Hz repetition rate with a pulse width of 16 ns. The standard deviation of laser pulse intensity for consecutive 100 shots from the mean pulse intensity is less than 1.05%. A spectral linewidth of less than 0.5 pm with a frequency jitter of about 14 fm over30 min is obtained.
基金Supported by Science and Technology Support Plan Project of Chengde,China,No.201701A072.
文摘BACKGROUND Pheochromocytoma is a rare catecholamines-secreting tumor arising from chromaffin cells in the adrenal medulla.It classically presents with paroxysmal hypertension,headaches,palpitations,sweating,and metabolic disorders.Atypical presentations such as acute myocardial infarction,heart failure,cardiomyopathy,stroke,and transient erythrocytosis have been infrequently documented.CASE SUMMARY We describe the case of a 72-year-old man diagnosed with pheochromocytoma presenting with non-ST segment elevation myocardial infarction,heart failure,and transient erythrocytosis with nonobstructed coronary arteries.This was his second heart attack.The patient was previously diagnosed with myocardial infarction,and an immense mass was found on the left adrenal gland 3 years prior.Based on clinical and laboratory findings,a diagnosis of pheochromocytoma was confirmed.His coronary angiogram showed nonobstructed coronary arteries except for a myocardial bridge in the left anterior descending branch.This was a form of type-2 myocardial infarction.The myocardial cell lesions were caused by sudden secretion of catecholamines by the pheochromocytoma.Even more atypically,his hemoglobin level was obviously elevated at admission,but after a few days of treatment with an alpha-adrenergic receptor blocker,it dropped to normal levels without additional treatment.CONCLUSION Pheochromocytoma may be a cause of acute myocardial infarction,heart failure,and transient erythrocytosis.
文摘The aim of this paper is to solve the problems that the existing method of critical production of gas cap reservoir is only suitable for single-phase flow, and the method of critical production of gas cap reservoir under water-flooding is still blank. In this paper, the relationships between dynamic and static equilibrium, plane radial flow theory, oil-water infiltration method and three-dimensional seepage field decomposition theory, were applied to study a calculation method for critical production of directional wells and horizontal wells. Furthermore, the effects of different factors on critical output were studied, such as horizontal permeability, ratio of horizontal permeability to vertical permeability, length of horizontal section, effective thickness, viscosity of crude oil and water content etc. Results show that the critical production increases with the increment of the horizontal permeability, the ratio of the vertical permeability to the horizontal permeability, the reservoir thickness and the horizontal well length;when the viscosity of crude oil is small, the critical production decreases first and then increases with the increase of water content;when the viscosity of crude oil is high, the critical production increases continuously with the increase of water content. This study could provide theoretical and technical guidance for changing of the working system of oil wells. It can avoid gas channeling and improve the development effect.
基金supported by the Establishment of Sino-Austria“Belt and Road”Joint Laboratory on Traditional Chinese Medicine for Severe Infectious Diseases and Joint Research(No.2020YFE0205100)the National Key Research and Development Program of China(No.2020YFA0908000)+8 种基金the Innovation Team and Talents Cultivation Program of the National Administration of Traditional Chinese Medicine(China)(No.ZYYCXTD-C-202002)the National Natural Science Foundation of China(No.82074098,81841001)the Fundamental ResearchFunds for the Central Public Welfare Research Institutes(China)(No.ZZ13-ZD-07,ZXKT18003,ZZ14-YQ-050,ZZ14-ND-010,ZZ15-ND-10,ZZ14-FL-002,ZZ14-YQ059,ZZ15-YQ-063)Shenzhen Science and Technology Innovation Commission(Guangdong,China)(No.JCYJ20210324115800001 and JCYJ20210324114014039)the National Key R&D Program of China Key projects for international cooperation on science,technology and innovation(No.2020YFE0205100)the Shenzhen Medical Research Fund of Shenzhen Medical Academy of Research and Translation(Guangdong,China)(No.B2302051)the Distinguished Expert Project of Sichuan Province Tianfu Scholar(China)(No.CW202002)China Academy of Chinese MedicalSciencess(CACMS)InnovationFund(No.CI2023E002)State Key Laboratory for Quality Ensurance and Sustainable Use of Dao-di Herbs.
文摘Sepsis,a life-threatening condition triggered by a dysregulated host response to infection,remains a major challenge for therapeutic intervention.Despite the growing interest in immunomodulatory strategies for sepsis treatment,the effects and mechanisms of these approaches on the organ-specific inflammatory and immunosuppressive states induced by sepsis are poorly understood.According to existing studies,capsaicin(CPS)has pharmacological effects such as analgesic,antipruritic,hypolipidemia,hypoglycemia,anti-inflammatory and antibacterial,and antitumor activity.1 However,the effectiveness of CPs in treating sepsis is still unknown.
文摘Architecturat heritage conservation is an important field in architectural research. The Hui-styte vernacutar dwetling is an essentialarchitectural heritage of China. Its hollow watt system, with horsehead-like upper corners, is a distinct architecturat feature that is worth preserving. However, the thermat performance of the hollow watt is relatively poor by today＇s standard. The current study developed a novel approach, whereby foam concrete was used to fill the voids inside the holtow watt to improve its thermat resistance. This approach was deemed cost effective, easy to learn, and capable of preserving the architectural integrity of the watt. Different types of foam concrete were prepared and tested. Testing results showed that the material properties of foam concrete are suitabte for thermaUy upgrading the hollow watt system. Ctimate chamber testing was conducted to investigate the effectiveness of the proposed thermat upgrading strategy. The testing resutts suggested that tilting the voids with foam concrete can effectively improve the overall thermal resistance of the holtow watt system by 24%, which is almost equal to the overall thermal resistance when using the more expensive commercial inorganic stucco system.
基金the National Natural Science Foundation of China(No.51608104 and No.51878139)Natural Science Foundation of Jiangsu Province(No.SBK2015043274)Jiangsu Southeast University Testing and Inspection Technology Company.
文摘Detailed survey and inspection of the structure of the lecture hall of the Anyuan Miners’Club were conducted during a restoration project.Nondestructive inspection measures were used to assess the physical and mechanical conditions of the structure.The brick and wood structures of the building were tested,the overall bearing capacity was calculated,and a safety appraisal was conducted in accordance with the codes and standards of the existing building.Inspection results provide architects and construction engineers with reliable data to develop a preservation plan and ensure the safety of the heritage building.
基金supported by the National Basic Research Program of China(2011CB710706)the National Natural Science Foundation of China(51210011,61374025)
文摘In this paper, an approach to optimize set points is proposed for controlled Organic Rankine Cycle(ORC)systems. Owing to both disturbances and variations of operating point existing in ORC systems, it is necessary to optimize the set points for controlled ORC systems so as to improve the energy conversion efficiency. At first, the optimal set points of controlled ORC systems are investigated by revisiting performance analysis and optimization of ORC systems. The expected set points of the evaporating pressure and the temperature at evaporator outlet are then determined by combining genetic algorithm with least squares support vector machine(GA-LSSVM). Simulation results show that the predicted results by GA-LSSVM can be regarded as the optimal set points of controlled ORC systems with varying operating conditions.
