Atherosclerosis(AS) is a lipid-driven chronic inflammatory disease occurring at the arterial subendothelial space. Macrophages play a critical role in the initiation and development of AS. Herein,targeted codelivery o...Atherosclerosis(AS) is a lipid-driven chronic inflammatory disease occurring at the arterial subendothelial space. Macrophages play a critical role in the initiation and development of AS. Herein,targeted codelivery of anti-miR 155 and anti-inflammatory baicalein is exploited to polarize macrophages toward M2 phenotype, inhibit inflammation and treat AS. The codelivery system consists of a carrier-free strategy(drug-delivering-drug, DDD), fabricated by loading anti-miR155 on baicalein nanocrystals,named as baicalein nanorods(BNRs), followed by sialic acid coating to target macrophages. The codelivery system, with a diameter of 150 nm, enables efficient intracellular delivery of anti-miR155 and polarizes M1 to M2, while markedly lowers the level of inflammatory factors in vitro and in vivo. In particular, intracellular fate assay reveals that the codelivery system allows for sustained drug release over time after internalization. Moreover, due to prolonged blood circulation and improved accumulation at the AS plaque, the codelivery system significantly alleviates AS in animal model by increasing the artery lumen diameter, reducing blood pressure, promoting M2 polarization, inhibiting secretion of inflammatory factors and decreasing blood lipids. Taken together, the codelivery could potentially be used to treat vascular inflammation.展开更多
Electroacupuncture has traditionally been used to treat pain, but its effect on pain following brachial plexus injury is still unknown. In this study, rat models of an avulsion injury to the left brachial plexus root ...Electroacupuncture has traditionally been used to treat pain, but its effect on pain following brachial plexus injury is still unknown. In this study, rat models of an avulsion injury to the left brachial plexus root （associated with upper-limb chronic neuropathic pain） were given electroacupuncture stimulation at bilateral Quchi （LIll）, Hegu （LI04）, Zusanli （ST36） and Yanglingquan （GB34）. After electroacupuncture therapy, chronic neuropathic pain in the rats＇ upper limbs was significantly attenuated. Immunofluorescence staining showed that the expression of β-endorphins in the arcuate nucleus was significantly increased after therapy. Thus, experimental findings indi- cate that electroacupuncture can attenuate neuropathic pain after brachial plexus injury through upregulating β-endorphin expression.展开更多
When condensation occurs in supersonic flow fields, the flow is thected by the latent heat released. In the present study, Navier-Stokes equations were solved numerically using a 3rd-order MUSCL type TVD finitediffere...When condensation occurs in supersonic flow fields, the flow is thected by the latent heat released. In the present study, Navier-Stokes equations were solved numerically using a 3rd-order MUSCL type TVD finitedifference scheme with a second-order fractionabetep for time integration. Baldwin-Lomax model, that is the algebraic model, called the zero equation model was used in the computations. The effects of initial conditions (initial degree of supersaturation and total temperature in the reservoir) on condensing fiow of moist air in a supersonic circular half nozzle were investigated. In this case, the effect of condensation on the boundary layer was also discussed in detail. As a result, the simulated flow fields were compared with experimental data in good agreement, and the velocity and temperature profiles were largely changed by condensation.展开更多
CaCu3Ti4O12 ceramics substituted by Mg for Ca were prepared by the solid state reaction method. The crystal structures, microstructures, and dielectric properties of the Ca1-xMgxCu3Ti4O12 ceramics were investigated. A...CaCu3Ti4O12 ceramics substituted by Mg for Ca were prepared by the solid state reaction method. The crystal structures, microstructures, and dielectric properties of the Ca1-xMgxCu3Ti4O12 ceramics were investigated. At lower doping concentrations, the substitution of Mg for Ca caused a decreased lattice constant, while at higher doping concentrations, some of the Mg dopants started to replace Ti and resulted in an increased lattice constant, and some could also replace Cu due to the similar ion radius between Mg and Cu ions. Mg doping was found to promote the grain growth of Ca1-xMgxCu3Ti4O12 ceramics during sintering. Grain boundary resistance of the Ca1-xMgxCu3Ti4O12 ceramics was found to be increased by Mg doping. Enhanced dielectric properties was observed in the Ca1-xMgxCu3Ti4O12 ceramics with x=0.05 for the frequency range from i kHz to 20 kHz. For other doping concentrations, the dielectric losses of Ca1-xMgxCu3Ti4O12 ceramics were generally lowered.展开更多
An 8-week feeding trial was conducted to determine the optimal dietary protein-to-lipid ratio for juvenile Nibea albiflora with an initial weight of(11.76 ± 0.20) g.Nine experimental diets containing different co...An 8-week feeding trial was conducted to determine the optimal dietary protein-to-lipid ratio for juvenile Nibea albiflora with an initial weight of(11.76 ± 0.20) g.Nine experimental diets containing different concentrations of protein(40%,47%,or 54%) and lipids(5%,9%,or 13%) in a 3 × 3 factorial experimental design were tested in triplicate groups of fish,while the protein-to-energy(P/E) ratios of the diets varied in the range of 19.74–28.32 mg k J^(-1).Results showed that fish fed diets containing 9% or 13% lipids with 54% protein exhibited significantly higher weight gains and specific growth rates than those fed other diets.The feed conversion rate of fish fed the diet with 40% protein and 5% lipids was significantly poorer than that of fish fed other diets.The protein efficiency rate of fish fed diets with 5% lipids was significantly lower than that of fish fed 9% or 13% lipid diets.Carcass lipid and energy contents were positively correlated with dietary lipid level regardless of protein level.Fish fed a 54% protein diet showed the highest trypsin activity.The intestinal lipase activity of fish fed the diet containing 13% lipids was significantly higher than that of fish fed 5% or 9% lipid diets.These results demonstrate the high protein dietary requirements of N.albiflora.A diet containing 54% protein and 9%–13% lipids with a P/E ratio of 26.2–27.81 mg protein k J^(-1) can be considered optimal for juvenile N.albiflora.展开更多
Difunctionalization of alkynes represents a powerful and straightforward approach to the synthesis of complex molecules.However,the radical difunctionalization of alkynes mediated by bifunctional reagents remains chal...Difunctionalization of alkynes represents a powerful and straightforward approach to the synthesis of complex molecules.However,the radical difunctionalization of alkynes mediated by bifunctional reagents remains challenging and underexplored,despite significant progress having been made in alkene difunctionalization.Here,we report a novel arylsulfonylacetate skeleton in which aryl rings are attached to acetates through SO_(2),serving as a powerful bifunctional reagent for the alkylarylation of alkynes via vinyl-radical intermediate under photoredox conditions.This modular bifunctional reagent enables the simultaneous incorporation of a wide range of functional groups,including(hetero)aryl ring and alkyl carboxylate into alkynes,resulting in synthetically valuable all-carbon tetrasubstituted alkene derivatives.This transformation is distinguished by its redox-neutral nature,readily accessible starting materials,compatibility with diverse functional groups and its capacity to facilitate convergent synthesis.The utility of this approach was further demonstrated by the late-stage functionalization of complex molecules and the preparation of fluorescent molecules and anti-cancer drugs.展开更多
The rapid recombination of charge carriers in piezoelectric materials has always been the problem that limits their piezoelectric performance for removal of organic pollutants in water.Herein,we construct a piezoelect...The rapid recombination of charge carriers in piezoelectric materials has always been the problem that limits their piezoelectric performance for removal of organic pollutants in water.Herein,we construct a piezoelectric Ba TiO_(3)/MoS_(2)(BTO/MS)that follows a type II heterojunction charge transfer system to inhibit the recombination of electron-hole(e^(-)-h^(+))pairs,which is beneficial to the activation of peroxymonosulfate(PMS)for the removal of antibiotic ornidazole(ORZ)pollutants.The optimal ratio of BTO/MS for ORZ degradation under the piezo/PMS process is 13.9,3.6,62.1 and 2.0 times higher than that of the BTO/piezo,MS/piezo,(BTO/MS)/PMS and(BTO/MS)/piezo processes,respectively.The high efficiency charge separation in the piezoelectric heterojunction of BTO/MS promotes the activation of PMS,resulting in the synergy of pizeocatalysis and PMS oxidation during the process of ORZ degradation.This study provides an idea for enhancing piezo-activation of PMS by constructing heterojunctions in piezoelectric materials.展开更多
Skeletal interoception regulates bone homeostasis through the prostaglandin E2(PGE2)concentration in bone.Vertebral endplates undergo ossification and become highly porous during intervertebral disc degeneration and a...Skeletal interoception regulates bone homeostasis through the prostaglandin E2(PGE2)concentration in bone.Vertebral endplates undergo ossification and become highly porous during intervertebral disc degeneration and aging.We found that the PGE2 concentration was elevated in porous endplates to generate spinal pain.Importantly,treatment with a high-dose cyclooxygenase 2 inhibitor(celecoxib,80 mg·kg−1 per day)decreased the prostaglandin E2 concentration and attenuated spinal pain in mice with lumbar spine instability.However,this treatment impaired bone formation in porous endplates,and spinal pain recurred after discontinuing the treatment.Interestingly,low-dose celecoxib(20 mg·kg−1 per day,which is equivalent to one-quarter of the clinical maximum dosage)induced a latent inhibition of spinal pain at 3 weeks post-treatment,which persisted even after discontinuing treatment.Furthermore,when the prostaglandin E2 concentration was maintained at the physiological level with low-dose celecoxib,endplate porosity was reduced significantly,which was associated with decreased sensory nerve innervation and spinal pain.These findings suggest that low-dose celecoxib may help to maintain skeletal interoception and decrease vertebral endplate porosity,thereby reducing sensory innervation and spinal pain in mice.展开更多
Pore characteristics have been identified as key design parameters for osteoimmunomodulation.The strategy reported here is to create an appropriate immune microenvironment by regulating pore characteristics of scaffol...Pore characteristics have been identified as key design parameters for osteoimmunomodulation.The strategy reported here is to create an appropriate immune microenvironment by regulating pore characteristics of scaffolds,thereby promoting early angiogenesis and enhancing osteogenesis.A series of collagen/nanohydroxyapatite(Col/nHAP)composite scaffolds with ordered lamellar structures and different layer spacings were prepared by mimicking the ordered lamellar topology of the bone matrix.Our research indicated that the layer spacing and ordered topology of the scaffold exerted an important influence on phenotype transformation of macrophages and the secretion of angiogenic factors.The Col/nHAP-O(135)with large layer spacing not only supported cell attachment and diffusion in vitro,but also promoted early angiogenesis by timely switching from M1 to M2 macrophage phenotype.In vivo data showed that the layer spacing and the ordered structure of the scaffold synergistically regulated the inflammatory response and triggered macrophages to secrete more angiogenesis related cytokines.Col/nHAP-O(135)considerably promoted the neovascularization and new bone formation in the defect site,indicating that Col/nHAPO(135)could significantly enhance the osteogenic activity of stem cells with the involvement of macrophages.展开更多
The search for a suitable cocatalyst for graphitic carbon nitride(g-C_(3)N_(4)) to realize efficient photocatalytic hydrogen(H_(2)) evolution has been regarded as one of the most valid tactics to alleviate energy cris...The search for a suitable cocatalyst for graphitic carbon nitride(g-C_(3)N_(4)) to realize efficient photocatalytic hydrogen(H_(2)) evolution has been regarded as one of the most valid tactics to alleviate energy crisis.Herein,a ternary Pt-tipped Au nanorods(Pt-Au)/g-C_(3)N_(4) heterostructure is constructed,which shows excellent H_(2) production performance in visible and near-infrared(NIR) region,especially in NIR region with a rate of 51.6 μmol g^(-1)h^(-1).Therein,not only is the optical absorption ability of g-C_(3)N_(4) broadened,the light absorption range is also extended to NIR region through introduction of Pt-Au architectures.Besides,analysis of the hot electrons generated in energy relaxation of plasmon indicates hot electron transfers fromexcited Au nanorods to Pt nanoparticles,resulting in H_(2) evolution.Compared with bare g-C_(3)N_(4),the superior photocatalytic activity could be attributed to the surface plasmon resonance effect(SPR) of Au nanorods and the electron-sink function of Pt nanoparticles.This work provides an insight into the improvement of photocatalytic performance via combination of NIR-responsive plasmon metal with photocatalysts.展开更多
In this paper,we prove that for holonomic nonconservative dynamical system the Poincare and Poincaré-Cartan integral invariants do not exist.Instead of them,we introduce the integral variants of Poincaré Car...In this paper,we prove that for holonomic nonconservative dynamical system the Poincare and Poincaré-Cartan integral invariants do not exist.Instead of them,we introduce the integral variants of Poincaré Cartan's type and of Poincaré's type for holonomie noneonservative dynamical systems,and use these variants to solve the problem of nonlinear vibration.We also prove that the integral invariants intro- duced in references[1]and[2]are merely the basic integral variants given by this paper.展开更多
The Middle Proterozoic Chartai Group separated by two unconformities consists of three depositional se-quences: the Shujigou Formation-Zenglongchang Formation (DS Ⅰ), the Agulugou Formation (DS Ⅱ), andthe Liuhongwan...The Middle Proterozoic Chartai Group separated by two unconformities consists of three depositional se-quences: the Shujigou Formation-Zenglongchang Formation (DS Ⅰ), the Agulugou Formation (DS Ⅱ), andthe Liuhongwan Formation (DS Ⅲ). The carbonate platform and back-platform basin are the basic environ-ment model of the Chartai Group. The syndepositional faults on the oceanward side of the carbonate platformand large-scale slumping in the soft sediments are important marks of facies tracts. The newly establishedZenglongchan uplifting, an epeirogenetic uplifting, plays an important role in the formation of thepalaeogeographic framework of the Chartai Group. The stratigraphic correlation between the Chartai Groupand the Bayan Obo Group is made for the first time by using sequence stratigraphic principle and model estab-lished by P.R. Vail. The Chartai Group, which was deposited on the northern passive continental margin of theNorth China platfom, represents the platform cover.展开更多
Techniques using Coanda effect have been applied to the fiuid control devices. In this field, experimental studies were so far performed for the spiral jet obtained by the Coanda jet issuing from a conical cylinder wi...Techniques using Coanda effect have been applied to the fiuid control devices. In this field, experimental studies were so far performed for the spiral jet obtained by the Coanda jet issuing from a conical cylinder with an annular slit, thrust vectoring of supersonic Coanda jets and so on. It is important from the viewpoints of effective applications to investigate the characteristics of the supersonic Coanda jet in detail. In the present study the effects of pressure ratios and nozzle configurations on the characteristics of the supersonic Coanda jet have been investigated experhoentally by a schlieren optical method and pressure measurements. Furthermore, Navier-Stokes equations were solved numerically using a 2nd-order TVD finite-volume scheme with a 3rd-rorder three stage Runge-Kutta method for time integration. k - ε model was used in the computations. The effects of initial conditions on Coandaflow were investigated numerically As a result, the simulated flow helds were compared with experimental data in good agreement qualitatively.展开更多
Based on the databases of soils, meteorology, crop production, and agricultural management, changes in the soil organic carbon (SOC) of agro ecosystems in Jiangsu Province were simulated by using a soil organic carbo...Based on the databases of soils, meteorology, crop production, and agricultural management, changes in the soil organic carbon (SOC) of agro ecosystems in Jiangsu Province were simulated by using a soil organic carbon model with a linkage of GIS. Four data sets of soil organic carbon measured from various field experiments in Jiangsu Province were used to validate the model. It was demonstrated that the model simulation in general agreed with the field measurements. Model simulation indicated that the SOC content in approximately 77% of the agricultural soils in Jiangsu Province has increased since the Second National Soil Survey completed in the early 1980s. Compared with the values in 1985, the SOC content in 2000 was estimated to increase by 1.03.0 g kg 1 for the north and the coastal areas of the province, and by 3.55.0 g kg 1 for the region of Tai Lake in the south. A slight decrease (about 0.51.5 g kg 1 ) was estimated for the central region of Jiangsu Province and the Nanjing Zhenjiang hilly area. Model prediction for 2010 A.D. under two scena rios, i.e., with 30 and 50% of the harvested crop straw incorporation, suggested that the SOC in Jiangsu Province would increase, and thus that the agricultural soils would have potential as organic carbon storage. The incorporation of crop straw into soils is of great benefit to increase soil carbon storage, consequently to benefit the control of the rise of atmospheric CO 2 concentration and to maintain the sustainable development of agriculture.展开更多
Nine oil-gas pipelines wander along the Belt and Road Initiative like gigantic steel dragons,and my routine work here is coordination of gas supply and transportation.Three year ago,I joined SINO-PIPELINE Internationa...Nine oil-gas pipelines wander along the Belt and Road Initiative like gigantic steel dragons,and my routine work here is coordination of gas supply and transportation.Three year ago,I joined SINO-PIPELINE International Company Limited(SPI)upon my graduation from college.I got nothing but my young blood and aspiration.Thanks to my experience of Russian Translation,I was recruited as a member in the secretariat of the Turkmenistan-Uzbekistan-Kazakhstan-China Gas Pipeline Operation Coordination Committee,and my responsibility is communication and coordination of gas supply and transportation.展开更多
Gut microbiota-derived metabolites influence host physiology and pathology,where short-chain fatty acids(SCFAs)are the main class of gut microbiota-derived metabolites.[1]SCFAs are fatty acids containing 1 to 6 carbon...Gut microbiota-derived metabolites influence host physiology and pathology,where short-chain fatty acids(SCFAs)are the main class of gut microbiota-derived metabolites.[1]SCFAs are fatty acids containing 1 to 6 carbon atoms,including acetate,propionate,butyrate,and pentanoate,which provide 6%to 10%of the body’s total daily energy and 60%to 70%of the colonic epithelial energy needed.[2]Anaerobic bacteria principally generate the SCFAs[1]in the intestine.Once produced,SCFAs are mainly absorbed in the colon(90%–95%),reach circulation,and play roles for distal organs and tissues.[2]展开更多
We demonstrate a photon-sensitive,three-dimensional(3D)camera by active near-infrared illumination and fast time-of-flight gating.It uses picosecond pump pulses to selectively upconvert the backscattered photons accor...We demonstrate a photon-sensitive,three-dimensional(3D)camera by active near-infrared illumination and fast time-of-flight gating.It uses picosecond pump pulses to selectively upconvert the backscattered photons according to their spatiotemporal modes via sum-frequency generation in a χ^(2) nonlinear crystal,which are then detected by an electron-multiplying CCD with photon sensitive detection.As such,it achieves sub-millimeter depth resolution,exceptional noise suppression,and high detection sensitivity.Our results show that it can accurately reconstruct the surface profiles of occluded targets placed behind highly scattering and lossy obscurants of14 optical depth(round trip),using only milliwatt illumination power.This technique may find applications in biomedical imaging,environmental monitoring,and wide-field light detection and ranging.展开更多
When condensation occurs in a supersonic flow field, the flow is affected by the latent heat released. In the present study, a condensing flow was produced by an expansion of moist air in a supersonic circular nozzle,...When condensation occurs in a supersonic flow field, the flow is affected by the latent heat released. In the present study, a condensing flow was produced by an expansion of moist air in a supersonic circular nozzle, and, by inserting a wedge-type shock generator placed in the supersonic part of the nozzle, the experimental investigations were carried out to clarify the effect of condensation on the normal shock wave and the boundary layer. As a result, the position of the shock wave relative to the condensation zone was discussed, together with the effect of condensation on pressure fiuctuations. Furthermore, a compressible viscous two-phase flow of moist air in a supersonic half nozzle was calculated to investigate the effect of condensation on boundary layer.展开更多
This paper presents the development process of the Jiangnan Civilization under the specific condition of the Yangtze River Delta,where numerous rivers and waterways have worked together as a natural and cultural matri...This paper presents the development process of the Jiangnan Civilization under the specific condition of the Yangtze River Delta,where numerous rivers and waterways have worked together as a natural and cultural matrix of the canal for thousands of years.To preserve it as a heritage,it is crucial to recognize that the local civilization has very much benefited from the flourishing natural and artificial network of waterways that is an indivisible part of the Grand Canal.This significant characteristic makes the canal as a heritage different from the present concept of "cultural route."展开更多
The efficient activation and utilization of peroxymonosulfate(PMS)in PMS-based advanced oxidation processes is a high-priority target for the removal of organic contaminants.This work introduces a water vortex-driven ...The efficient activation and utilization of peroxymonosulfate(PMS)in PMS-based advanced oxidation processes is a high-priority target for the removal of organic contaminants.This work introduces a water vortex-driven piezoelectric effect from few-odd-layered MoS_(2)into the PMS activation to remove benzotriazole(BTR)and other organic contaminants from the water.Approximately 91.1%of BTR can be removed by the MoS_(2)piezo-activated PMS process with a reaction rate constant of 0.428 min1,which is 2.09 times faster than the sum of the individual MoS_(2),water vortex,and piezocatalysis rates.Meanwhile,the PMS utilization efficiency reached 0.0147 in the water vortex-driven piezo-activation system,which is 3.97 times that of the sum from the vortex/PMS and MoS_(2)/PMS systems.These results demonstrate that the presence of MoS_(2)under a water vortex can trigger a piezoelectric potential and generate abundant free electrons to activate PMS to generate various active species for degradation of organic contaminants.展开更多
基金supported by the National Natural Science Foundation of China(Nos.81872823 and 81773826)the Double First-Class(CPU2018PZQ13,China)of the China Pharmeutical University+2 种基金the Ministry of Science and Technology of China(2018ZX09711001)the Shanghai Science and Technology Committee(19430741500,China)the Key Laboratory of Modern Chinese Medicine Preparation of Ministry of Education of Jiangxi University of traditional Chinese Medicine(TCM201905,China)
文摘Atherosclerosis(AS) is a lipid-driven chronic inflammatory disease occurring at the arterial subendothelial space. Macrophages play a critical role in the initiation and development of AS. Herein,targeted codelivery of anti-miR 155 and anti-inflammatory baicalein is exploited to polarize macrophages toward M2 phenotype, inhibit inflammation and treat AS. The codelivery system consists of a carrier-free strategy(drug-delivering-drug, DDD), fabricated by loading anti-miR155 on baicalein nanocrystals,named as baicalein nanorods(BNRs), followed by sialic acid coating to target macrophages. The codelivery system, with a diameter of 150 nm, enables efficient intracellular delivery of anti-miR155 and polarizes M1 to M2, while markedly lowers the level of inflammatory factors in vitro and in vivo. In particular, intracellular fate assay reveals that the codelivery system allows for sustained drug release over time after internalization. Moreover, due to prolonged blood circulation and improved accumulation at the AS plaque, the codelivery system significantly alleviates AS in animal model by increasing the artery lumen diameter, reducing blood pressure, promoting M2 polarization, inhibiting secretion of inflammatory factors and decreasing blood lipids. Taken together, the codelivery could potentially be used to treat vascular inflammation.
基金supported by the Project of Ministry of Health(Comprehensive Research on Brachial Plexus Injury),No.13D22270800 from the National Natural Science Foundation of China2011 Shanghai Medical College Young Scientist Fund of Fudan University,No.11L-24
文摘Electroacupuncture has traditionally been used to treat pain, but its effect on pain following brachial plexus injury is still unknown. In this study, rat models of an avulsion injury to the left brachial plexus root （associated with upper-limb chronic neuropathic pain） were given electroacupuncture stimulation at bilateral Quchi （LIll）, Hegu （LI04）, Zusanli （ST36） and Yanglingquan （GB34）. After electroacupuncture therapy, chronic neuropathic pain in the rats＇ upper limbs was significantly attenuated. Immunofluorescence staining showed that the expression of β-endorphins in the arcuate nucleus was significantly increased after therapy. Thus, experimental findings indi- cate that electroacupuncture can attenuate neuropathic pain after brachial plexus injury through upregulating β-endorphin expression.
文摘When condensation occurs in supersonic flow fields, the flow is thected by the latent heat released. In the present study, Navier-Stokes equations were solved numerically using a 3rd-order MUSCL type TVD finitedifference scheme with a second-order fractionabetep for time integration. Baldwin-Lomax model, that is the algebraic model, called the zero equation model was used in the computations. The effects of initial conditions (initial degree of supersaturation and total temperature in the reservoir) on condensing fiow of moist air in a supersonic circular half nozzle were investigated. In this case, the effect of condensation on the boundary layer was also discussed in detail. As a result, the simulated flow fields were compared with experimental data in good agreement, and the velocity and temperature profiles were largely changed by condensation.
基金supported by the National Natural Science Foundation of China (Grant Nos.60661001,60844008)the Program for Changjiang Scholars and Innovative Research Team in University (No.IRT0730)the Program for Innovative Research Team of Nanchang University
文摘CaCu3Ti4O12 ceramics substituted by Mg for Ca were prepared by the solid state reaction method. The crystal structures, microstructures, and dielectric properties of the Ca1-xMgxCu3Ti4O12 ceramics were investigated. At lower doping concentrations, the substitution of Mg for Ca caused a decreased lattice constant, while at higher doping concentrations, some of the Mg dopants started to replace Ti and resulted in an increased lattice constant, and some could also replace Cu due to the similar ion radius between Mg and Cu ions. Mg doping was found to promote the grain growth of Ca1-xMgxCu3Ti4O12 ceramics during sintering. Grain boundary resistance of the Ca1-xMgxCu3Ti4O12 ceramics was found to be increased by Mg doping. Enhanced dielectric properties was observed in the Ca1-xMgxCu3Ti4O12 ceramics with x=0.05 for the frequency range from i kHz to 20 kHz. For other doping concentrations, the dielectric losses of Ca1-xMgxCu3Ti4O12 ceramics were generally lowered.
基金supported by grants from the Na-tional Natural Science Foundation of China(No.41476127)the Science and Technology Planning Project of Zhejiang Province(No.2016F50038)+1 种基金the Science and Technology Planning Project of ZhouShan City(No.2015C31010)the Scientific Research Foundation of Zhejiang Ocean Universtiy(No.2014Q1434)
文摘An 8-week feeding trial was conducted to determine the optimal dietary protein-to-lipid ratio for juvenile Nibea albiflora with an initial weight of(11.76 ± 0.20) g.Nine experimental diets containing different concentrations of protein(40%,47%,or 54%) and lipids(5%,9%,or 13%) in a 3 × 3 factorial experimental design were tested in triplicate groups of fish,while the protein-to-energy(P/E) ratios of the diets varied in the range of 19.74–28.32 mg k J^(-1).Results showed that fish fed diets containing 9% or 13% lipids with 54% protein exhibited significantly higher weight gains and specific growth rates than those fed other diets.The feed conversion rate of fish fed the diet with 40% protein and 5% lipids was significantly poorer than that of fish fed other diets.The protein efficiency rate of fish fed diets with 5% lipids was significantly lower than that of fish fed 9% or 13% lipid diets.Carcass lipid and energy contents were positively correlated with dietary lipid level regardless of protein level.Fish fed a 54% protein diet showed the highest trypsin activity.The intestinal lipase activity of fish fed the diet containing 13% lipids was significantly higher than that of fish fed 5% or 9% lipid diets.These results demonstrate the high protein dietary requirements of N.albiflora.A diet containing 54% protein and 9%–13% lipids with a P/E ratio of 26.2–27.81 mg protein k J^(-1) can be considered optimal for juvenile N.albiflora.
基金supported by the National Natural Science Foundation of China(21901199)Xi’an Jiaotong University(7121192002)。
文摘Difunctionalization of alkynes represents a powerful and straightforward approach to the synthesis of complex molecules.However,the radical difunctionalization of alkynes mediated by bifunctional reagents remains challenging and underexplored,despite significant progress having been made in alkene difunctionalization.Here,we report a novel arylsulfonylacetate skeleton in which aryl rings are attached to acetates through SO_(2),serving as a powerful bifunctional reagent for the alkylarylation of alkynes via vinyl-radical intermediate under photoredox conditions.This modular bifunctional reagent enables the simultaneous incorporation of a wide range of functional groups,including(hetero)aryl ring and alkyl carboxylate into alkynes,resulting in synthetically valuable all-carbon tetrasubstituted alkene derivatives.This transformation is distinguished by its redox-neutral nature,readily accessible starting materials,compatibility with diverse functional groups and its capacity to facilitate convergent synthesis.The utility of this approach was further demonstrated by the late-stage functionalization of complex molecules and the preparation of fluorescent molecules and anti-cancer drugs.
基金supported by Guangdong Basic and Applied Basic Research Foundation,China(No.2020B1515020038)the Pearl River Talent Recruitment Program of Guangdong Province(No.2019QN01L148),China。
文摘The rapid recombination of charge carriers in piezoelectric materials has always been the problem that limits their piezoelectric performance for removal of organic pollutants in water.Herein,we construct a piezoelectric Ba TiO_(3)/MoS_(2)(BTO/MS)that follows a type II heterojunction charge transfer system to inhibit the recombination of electron-hole(e^(-)-h^(+))pairs,which is beneficial to the activation of peroxymonosulfate(PMS)for the removal of antibiotic ornidazole(ORZ)pollutants.The optimal ratio of BTO/MS for ORZ degradation under the piezo/PMS process is 13.9,3.6,62.1 and 2.0 times higher than that of the BTO/piezo,MS/piezo,(BTO/MS)/PMS and(BTO/MS)/piezo processes,respectively.The high efficiency charge separation in the piezoelectric heterojunction of BTO/MS promotes the activation of PMS,resulting in the synergy of pizeocatalysis and PMS oxidation during the process of ORZ degradation.This study provides an idea for enhancing piezo-activation of PMS by constructing heterojunctions in piezoelectric materials.
基金supported by National Institute on Aging of the National Institutes of Health under Award Number R01 AG068997 and P01 AG066603(to X.C.).
文摘Skeletal interoception regulates bone homeostasis through the prostaglandin E2(PGE2)concentration in bone.Vertebral endplates undergo ossification and become highly porous during intervertebral disc degeneration and aging.We found that the PGE2 concentration was elevated in porous endplates to generate spinal pain.Importantly,treatment with a high-dose cyclooxygenase 2 inhibitor(celecoxib,80 mg·kg−1 per day)decreased the prostaglandin E2 concentration and attenuated spinal pain in mice with lumbar spine instability.However,this treatment impaired bone formation in porous endplates,and spinal pain recurred after discontinuing the treatment.Interestingly,low-dose celecoxib(20 mg·kg−1 per day,which is equivalent to one-quarter of the clinical maximum dosage)induced a latent inhibition of spinal pain at 3 weeks post-treatment,which persisted even after discontinuing treatment.Furthermore,when the prostaglandin E2 concentration was maintained at the physiological level with low-dose celecoxib,endplate porosity was reduced significantly,which was associated with decreased sensory nerve innervation and spinal pain.These findings suggest that low-dose celecoxib may help to maintain skeletal interoception and decrease vertebral endplate porosity,thereby reducing sensory innervation and spinal pain in mice.
基金the National Natural Science Foundation of China(No.31971270)the grant of Peak Climbing Project of Foshan Hospital of Traditional Chinese Medicine(CN)(No.202000190).
文摘Pore characteristics have been identified as key design parameters for osteoimmunomodulation.The strategy reported here is to create an appropriate immune microenvironment by regulating pore characteristics of scaffolds,thereby promoting early angiogenesis and enhancing osteogenesis.A series of collagen/nanohydroxyapatite(Col/nHAP)composite scaffolds with ordered lamellar structures and different layer spacings were prepared by mimicking the ordered lamellar topology of the bone matrix.Our research indicated that the layer spacing and ordered topology of the scaffold exerted an important influence on phenotype transformation of macrophages and the secretion of angiogenic factors.The Col/nHAP-O(135)with large layer spacing not only supported cell attachment and diffusion in vitro,but also promoted early angiogenesis by timely switching from M1 to M2 macrophage phenotype.In vivo data showed that the layer spacing and the ordered structure of the scaffold synergistically regulated the inflammatory response and triggered macrophages to secrete more angiogenesis related cytokines.Col/nHAP-O(135)considerably promoted the neovascularization and new bone formation in the defect site,indicating that Col/nHAPO(135)could significantly enhance the osteogenic activity of stem cells with the involvement of macrophages.
基金financially supported by the National Natural Science Foundation of China (Nos. 22162009 and 22006052)Key Laboratory of Solid Waste Resource Utilization and Environmental Protection of Haikou City。
文摘The search for a suitable cocatalyst for graphitic carbon nitride(g-C_(3)N_(4)) to realize efficient photocatalytic hydrogen(H_(2)) evolution has been regarded as one of the most valid tactics to alleviate energy crisis.Herein,a ternary Pt-tipped Au nanorods(Pt-Au)/g-C_(3)N_(4) heterostructure is constructed,which shows excellent H_(2) production performance in visible and near-infrared(NIR) region,especially in NIR region with a rate of 51.6 μmol g^(-1)h^(-1).Therein,not only is the optical absorption ability of g-C_(3)N_(4) broadened,the light absorption range is also extended to NIR region through introduction of Pt-Au architectures.Besides,analysis of the hot electrons generated in energy relaxation of plasmon indicates hot electron transfers fromexcited Au nanorods to Pt nanoparticles,resulting in H_(2) evolution.Compared with bare g-C_(3)N_(4),the superior photocatalytic activity could be attributed to the surface plasmon resonance effect(SPR) of Au nanorods and the electron-sink function of Pt nanoparticles.This work provides an insight into the improvement of photocatalytic performance via combination of NIR-responsive plasmon metal with photocatalysts.
基金Project supported by National Natural Science Foundation of China
文摘In this paper,we prove that for holonomic nonconservative dynamical system the Poincare and Poincaré-Cartan integral invariants do not exist.Instead of them,we introduce the integral variants of Poincaré Cartan's type and of Poincaré's type for holonomie noneonservative dynamical systems,and use these variants to solve the problem of nonlinear vibration.We also prove that the integral invariants intro- duced in references[1]and[2]are merely the basic integral variants given by this paper.
文摘The Middle Proterozoic Chartai Group separated by two unconformities consists of three depositional se-quences: the Shujigou Formation-Zenglongchang Formation (DS Ⅰ), the Agulugou Formation (DS Ⅱ), andthe Liuhongwan Formation (DS Ⅲ). The carbonate platform and back-platform basin are the basic environ-ment model of the Chartai Group. The syndepositional faults on the oceanward side of the carbonate platformand large-scale slumping in the soft sediments are important marks of facies tracts. The newly establishedZenglongchan uplifting, an epeirogenetic uplifting, plays an important role in the formation of thepalaeogeographic framework of the Chartai Group. The stratigraphic correlation between the Chartai Groupand the Bayan Obo Group is made for the first time by using sequence stratigraphic principle and model estab-lished by P.R. Vail. The Chartai Group, which was deposited on the northern passive continental margin of theNorth China platfom, represents the platform cover.
文摘Techniques using Coanda effect have been applied to the fiuid control devices. In this field, experimental studies were so far performed for the spiral jet obtained by the Coanda jet issuing from a conical cylinder with an annular slit, thrust vectoring of supersonic Coanda jets and so on. It is important from the viewpoints of effective applications to investigate the characteristics of the supersonic Coanda jet in detail. In the present study the effects of pressure ratios and nozzle configurations on the characteristics of the supersonic Coanda jet have been investigated experhoentally by a schlieren optical method and pressure measurements. Furthermore, Navier-Stokes equations were solved numerically using a 2nd-order TVD finite-volume scheme with a 3rd-rorder three stage Runge-Kutta method for time integration. k - ε model was used in the computations. The effects of initial conditions on Coandaflow were investigated numerically As a result, the simulated flow helds were compared with experimental data in good agreement qualitatively.
文摘Based on the databases of soils, meteorology, crop production, and agricultural management, changes in the soil organic carbon (SOC) of agro ecosystems in Jiangsu Province were simulated by using a soil organic carbon model with a linkage of GIS. Four data sets of soil organic carbon measured from various field experiments in Jiangsu Province were used to validate the model. It was demonstrated that the model simulation in general agreed with the field measurements. Model simulation indicated that the SOC content in approximately 77% of the agricultural soils in Jiangsu Province has increased since the Second National Soil Survey completed in the early 1980s. Compared with the values in 1985, the SOC content in 2000 was estimated to increase by 1.03.0 g kg 1 for the north and the coastal areas of the province, and by 3.55.0 g kg 1 for the region of Tai Lake in the south. A slight decrease (about 0.51.5 g kg 1 ) was estimated for the central region of Jiangsu Province and the Nanjing Zhenjiang hilly area. Model prediction for 2010 A.D. under two scena rios, i.e., with 30 and 50% of the harvested crop straw incorporation, suggested that the SOC in Jiangsu Province would increase, and thus that the agricultural soils would have potential as organic carbon storage. The incorporation of crop straw into soils is of great benefit to increase soil carbon storage, consequently to benefit the control of the rise of atmospheric CO 2 concentration and to maintain the sustainable development of agriculture.
文摘Nine oil-gas pipelines wander along the Belt and Road Initiative like gigantic steel dragons,and my routine work here is coordination of gas supply and transportation.Three year ago,I joined SINO-PIPELINE International Company Limited(SPI)upon my graduation from college.I got nothing but my young blood and aspiration.Thanks to my experience of Russian Translation,I was recruited as a member in the secretariat of the Turkmenistan-Uzbekistan-Kazakhstan-China Gas Pipeline Operation Coordination Committee,and my responsibility is communication and coordination of gas supply and transportation.
基金supported by the National Key R&D Program of China(No.2020YFC2005000)the National Science Foundation of China(No.82100775).
文摘Gut microbiota-derived metabolites influence host physiology and pathology,where short-chain fatty acids(SCFAs)are the main class of gut microbiota-derived metabolites.[1]SCFAs are fatty acids containing 1 to 6 carbon atoms,including acetate,propionate,butyrate,and pentanoate,which provide 6%to 10%of the body’s total daily energy and 60%to 70%of the colonic epithelial energy needed.[2]Anaerobic bacteria principally generate the SCFAs[1]in the intestine.Once produced,SCFAs are mainly absorbed in the colon(90%–95%),reach circulation,and play roles for distal organs and tissues.[2]
文摘We demonstrate a photon-sensitive,three-dimensional(3D)camera by active near-infrared illumination and fast time-of-flight gating.It uses picosecond pump pulses to selectively upconvert the backscattered photons according to their spatiotemporal modes via sum-frequency generation in a χ^(2) nonlinear crystal,which are then detected by an electron-multiplying CCD with photon sensitive detection.As such,it achieves sub-millimeter depth resolution,exceptional noise suppression,and high detection sensitivity.Our results show that it can accurately reconstruct the surface profiles of occluded targets placed behind highly scattering and lossy obscurants of14 optical depth(round trip),using only milliwatt illumination power.This technique may find applications in biomedical imaging,environmental monitoring,and wide-field light detection and ranging.
文摘When condensation occurs in a supersonic flow field, the flow is affected by the latent heat released. In the present study, a condensing flow was produced by an expansion of moist air in a supersonic circular nozzle, and, by inserting a wedge-type shock generator placed in the supersonic part of the nozzle, the experimental investigations were carried out to clarify the effect of condensation on the normal shock wave and the boundary layer. As a result, the position of the shock wave relative to the condensation zone was discussed, together with the effect of condensation on pressure fiuctuations. Furthermore, a compressible viscous two-phase flow of moist air in a supersonic half nozzle was calculated to investigate the effect of condensation on boundary layer.
文摘This paper presents the development process of the Jiangnan Civilization under the specific condition of the Yangtze River Delta,where numerous rivers and waterways have worked together as a natural and cultural matrix of the canal for thousands of years.To preserve it as a heritage,it is crucial to recognize that the local civilization has very much benefited from the flourishing natural and artificial network of waterways that is an indivisible part of the Grand Canal.This significant characteristic makes the canal as a heritage different from the present concept of "cultural route."
基金Open Project of State Key Laboratory of Urban Water Resource and Environment,Harbin Institute of Technology(ESK202102)the Guangdong Basic and Applied Basic Research Foundation(2020B1515020038)National Natural Science Foundation of China(22006052).
文摘The efficient activation and utilization of peroxymonosulfate(PMS)in PMS-based advanced oxidation processes is a high-priority target for the removal of organic contaminants.This work introduces a water vortex-driven piezoelectric effect from few-odd-layered MoS_(2)into the PMS activation to remove benzotriazole(BTR)and other organic contaminants from the water.Approximately 91.1%of BTR can be removed by the MoS_(2)piezo-activated PMS process with a reaction rate constant of 0.428 min1,which is 2.09 times faster than the sum of the individual MoS_(2),water vortex,and piezocatalysis rates.Meanwhile,the PMS utilization efficiency reached 0.0147 in the water vortex-driven piezo-activation system,which is 3.97 times that of the sum from the vortex/PMS and MoS_(2)/PMS systems.These results demonstrate that the presence of MoS_(2)under a water vortex can trigger a piezoelectric potential and generate abundant free electrons to activate PMS to generate various active species for degradation of organic contaminants.
