Paper-based microchips have different advantages,such as better biocompatibility,simple production,and easy handling,making them promising candidates for clinical diagnosis and other fields.This study describes ametho...Paper-based microchips have different advantages,such as better biocompatibility,simple production,and easy handling,making them promising candidates for clinical diagnosis and other fields.This study describes amethod developed to fabricate modular three-dimensional(3D)paper-based microfluidic chips based on projection-based 3D printing(PBP)technology.A series of two-dimensional(2D)paper-based microfluidic modules was designed and fabricated.After evaluating the effect of exposure time on the accuracy of the flow channel,the resolution of this channel was experimentally analyzed.Furthermore,several 3D paper-based microfluidic chips were assembled based on the 2D ones using different methods,with good channel connectivity.Scaffold-based 2D and hydrogel-based 3D cell culture systems based on 3D paper-based microfluidic chips were verified to be feasible.Furthermore,by combining extrusion 3D bioprinting technology and the proposed 3D paper-based microfluidic chips,multiorgan microfluidic chips were established by directly printing 3D hydrogel structures on 3D paperbased microfluidic chips,confirming that the prepared modular 3D paper-based microfluidic chip is potentially applicable in various biomedical applications.展开更多
Since projection-based 3D bioprinting(PBP)could provide high resolution,it is well suited for printing delicate structures for tissue regeneration.However,the low crosslinking density and low photo-crosslinking rate o...Since projection-based 3D bioprinting(PBP)could provide high resolution,it is well suited for printing delicate structures for tissue regeneration.However,the low crosslinking density and low photo-crosslinking rate of photocurable bioink make it difficult to print fine structures.Currently,an in-depth understanding of the is lacking.Here,a research framework is established for the analysis of printability during PBP.The gelatin methacryloyl(GelMA)-based bioink is used as an example,and the printability is systematically investigated.We analyze the photo-crosslinking reactions during the PBP process and summarize the specific requirements of bioinks for PBP.Two standard quantized models are established to evaluate 2D and 3D printing errors.Finally,the better strategies for bioprinting five typical structures,including solid organs,vascular structures,nerve conduits,thin-wall scaffolds,and micro needles,are presented.展开更多
Prosthesis implantation and fat transplantation are common breast reconstructionmethods.In general,prosthesis implantation alone does not achieve a realistic enough appearance,and fat transplantation alone is difficul...Prosthesis implantation and fat transplantation are common breast reconstructionmethods.In general,prosthesis implantation alone does not achieve a realistic enough appearance,and fat transplantation alone is difficult to achieve in the correct capacity.To date,no reports have focused on methods of combining fat with implanted prostheses for breast reconstruction.Using a newly designed bionic ink(i.e.,polyether F127 diacrylate(F127DA)&poly(ethylene glycol)diacrylate(PEGDA))and projection-based three-dimensional bioprinting(PBP),we report the development of a new method for printing porous prostheses.PEGDA was used to improve the printing precision of the prosthesis by increasing the gel point of F127DA and reducing the impact of external temperature.The compression modulus of the printed prosthesis was very close to that of prostheses currently used in clinical practice and to that of natural breasts.Finally,stromal vascular fraction gel(SVF-gel),a human fat extract,was injected into the pores of the synthesized prostheses to prepare a prosthesis mixed with adipose tissue.These were implanted subcutaneously in nude mice to observe their biological performance.After 14 and 28 days of observation,the prosthesis showed good biocompatibility,and adipose tissues grew well in and around the prosthesis.This result shows that a porous prosthesis containing pre-placed adipose tissues is a promising breast reconstruction material.展开更多
Chromium pollution due to leaching and weathering of chromite mine overburden in mine seepage water is a serious environmental problem. In an attempt to explore the indigenous chromate resistant and reducing bacteria ...Chromium pollution due to leaching and weathering of chromite mine overburden in mine seepage water is a serious environmental problem. In an attempt to explore the indigenous chromate resistant and reducing bacteria from chromite mine quarry seepage, 145 aerobic, heterotrophic bacteria were isolated from 14 mine seepage samples derived from chromite mines of Sukinda valley and Baula-Nuasahi belt in Orissa, India. A total of 109 isolates which were tolerant to 2 mM Cr(VI) showed different degrees of Cr(VI) reducing activ-ity in complex KSC medium and synthetic Vogel Bonner (VB) broth. Ten isolates belonging to genera like Pseudomonas, Acinetobacter, Alcaligenes, Cupriavidus and Corynebacterium were selected on the basis of their chromate reducing efficiency and it was found that they could reduce more than 50 and 75% of Cr(VI) in VB broth and KSC medium respectively. The sole Gram-positive isolate, Corynebacterium paurometabo-lum SKPD 1204 (MTCC 8730) showed maximum chromate reducing capacity in both VB broth (63.7%) and KSC medium (92%) and was capable of reducing nearly 95% of the total Cr(VI) in the mine seepage when it was grown in the mine seepage supplemented with 2% VB concentrate.展开更多
Using series iteration techniques identities and apply each of these identities in we derive a number of general double series order to deduce several hypergeometric reduction formulas involving the Srivastava-Daoust ...Using series iteration techniques identities and apply each of these identities in we derive a number of general double series order to deduce several hypergeometric reduction formulas involving the Srivastava-Daoust double hypergeometric function. The results presented in this article are based essentially upon the hypergeometric summation theorems of Kummer and Dixon.展开更多
In this paper, the Clarkson-Kruskal direct approach is employed to investigate the exact solutions of the 2-dimensionai rotationai Euler equations for the incompressible fluid. The application of the method leads to a...In this paper, the Clarkson-Kruskal direct approach is employed to investigate the exact solutions of the 2-dimensionai rotationai Euler equations for the incompressible fluid. The application of the method leads to a system of completely solvable ordinary differential equations. Several special cases are discussed and novel nonlinear exact solutions with respect to variables x and y are obtained. It is＇of interest to notice that the pressure p is obtained by the second kind of curvilinear integral and the coefficients of the nonlinear solutions are solitary wave type functions like tanh（ kt /2 ） and sech （kt/2） due to the rotational parameter k ≠ O. Such phenomenon never appear in the classical Euler equations wherein the Coriolis force arising from the gravity and Earth＇s rotation is ignored. Finally, illustrative numerical figures are attached to show the behaviors that the exact solutions may exhibit.展开更多
Si3N4 powder was synthesized by carbothermal re- duction nitridation reaction using sawdust as carbon source and introducing SiO2 by silica sol immersion. Effects of SiO2 content of silica sol, molding pressure, react...Si3N4 powder was synthesized by carbothermal re- duction nitridation reaction using sawdust as carbon source and introducing SiO2 by silica sol immersion. Effects of SiO2 content of silica sol, molding pressure, reaction temperature, reaction duration, and N2 flow rate on phase compositions and microstructure of result- ants were studied. The results show that using 7. 5 mass% SiO2 containing silica sol immersed sawdust as raw materials, the prepared Si3N4 powder is featured with high α-Si3N4 content, few impurities, etc. in the conditions of 1 450 ℃ of reaction temperature, 9 h of reaction duration, 400 mL ·min- 1 of N2 flow rate and 10 MPa of molding pressure.展开更多
Simulation of incompressible fluid flow-elastic structure interactions is targeted by using fully-Lagrangian mesh-free computational methods. A projection-based fluid model（moving particle semi-implicit（MPS）） is c...Simulation of incompressible fluid flow-elastic structure interactions is targeted by using fully-Lagrangian mesh-free computational methods. A projection-based fluid model（moving particle semi-implicit（MPS）） is coupled with either a Newtonian or a Hamiltonian Lagrangian structure model（MPS or HMPS） in a mathematically-physically consistent manner. The fluid model is founded on the solution of Navier-Stokes and continuity equations. The structure models are configured either in the framework of Newtonian mechanics on the basis of conservation of linear and angular momenta, or Hamiltonian mechanics on the basis of variational principle for incompressible elastodynamics. A set of enhanced schemes are incorporated for projection-based fluid model（Enhanced MPS）, thus, the developed coupled solvers for fluid structure interaction（FSI） are referred to as Enhanced MPS-MPS and Enhanced MPS-HMPS. Besides, two smoothed particle hydrodynamics（SPH）-based FSI solvers, being developed by the authors, are considered and their potential applicability and comparable performance are briefly discussed in comparison with MPS-based FSI solvers. The SPH-based FSI solvers are established through coupling of projection-based incompressible SPH（ISPH） fluid model and SPH-based Newtonian/Hamiltonian structure models, leading to Enhanced ISPH-SPH and Enhanced ISPH-HSPH. A comparative study is carried out on the performances of the FSI solvers through a set of benchmark tests, including hydrostatic water column on an elastic plate,high speed impact of an elastic aluminum beam, hydroelastic slamming of a marine panel and dam break with elastic gate.展开更多
Nuclear magnetic resonance (NMR) spectros-copy has become an important tool in modern biological research. NMR spectra image analysis can be used to analyze the kinetics of biomacromolecular conformational changes. Th...Nuclear magnetic resonance (NMR) spectros-copy has become an important tool in modern biological research. NMR spectra image analysis can be used to analyze the kinetics of biomacromolecular conformational changes. The relationship between the image parameters and the protein dynamics was investigated by using a small globular protein ω-conotoxin SO3 (ω-CTX SO3). The physical meanings of the image parameters were characterized from the results. Comparison of the data from the traditional integral area of specific resonance peaks method and the NMR image analysis method showed the advantages of using NMR spectra image analysis for kinetic analysis of two-state processes monitored by 1D proton NMR.展开更多
A projection-based reduced order model(ROM)based on the Fourier collocation method is proposed for compressible flows.The incorporation of localized artificial viscosity model and filtering is pursued to enhance the r...A projection-based reduced order model(ROM)based on the Fourier collocation method is proposed for compressible flows.The incorporation of localized artificial viscosity model and filtering is pursued to enhance the robustness and accuracy of the ROM for shock-dominated flows.Furthermore,for Euler systems,ROMs built on the conservative and the skew-symmetric forms of the governing equation are compared.To ensure efficiency,the discrete empirical interpolation method(DEIM)is employed.An alternative reduction approach,exploring the sparsity of viscosity is also investigated for the viscous terms.A number of one-and two-dimensional benchmark cases are considered to test the performance of the proposed models.Results show that stable computations for shock-dominated cases can be achieved with ROMs built on both the conservative and the skew-symmetric forms without additional stabilization components other than the viscosity model and filtering.Under the same parameters,the skew-symmetric form shows better robustness and accuracy than its conservative counterpart,while the conservative form is superior in terms of efficiency.展开更多
This note addresses diagnosis and performance degradation detection issues from an integrated viewpoint of functionality maintenance and cyber security of automatic control systems.It calls for more research attention...This note addresses diagnosis and performance degradation detection issues from an integrated viewpoint of functionality maintenance and cyber security of automatic control systems.It calls for more research attention on three aspects:(i)application of control and detection uni ed framework to enhancing the diagnosis capability of feedback control systems,(ii)projection-based fault detection,and complementary and explainable applications of projection-and machine learning-based techniques,and(iii)system performance degradation detection that is of elemental importance for today's automatic control systems.Some ideas and conceptual schemes are presented and illustrated by means of examples,serving as convincing arguments for research e orts in these aspects.They would contribute to the future development of capable diagnosis systems for functionality safe and cyber secure automatic control systems.展开更多
基金sponsored by the National Natural Science Foundation of China(No.52235007,YH)the Science Fund for Creative Research Groups of the National Natural Science Foundation of China(No.T2121004,YH)+3 种基金the NationalNatural Science Foundation of China(No.52305300,MJX)the Fellowship of China Postdoctoral Science Foundation(No.2022M722826,MJX)the National Natural Science Foundation of China(No.82203602,JW)the Zhejiang Provincial Natural Science Foundation of China(No.LQ22H160020,JW)。
文摘Paper-based microchips have different advantages,such as better biocompatibility,simple production,and easy handling,making them promising candidates for clinical diagnosis and other fields.This study describes amethod developed to fabricate modular three-dimensional(3D)paper-based microfluidic chips based on projection-based 3D printing(PBP)technology.A series of two-dimensional(2D)paper-based microfluidic modules was designed and fabricated.After evaluating the effect of exposure time on the accuracy of the flow channel,the resolution of this channel was experimentally analyzed.Furthermore,several 3D paper-based microfluidic chips were assembled based on the 2D ones using different methods,with good channel connectivity.Scaffold-based 2D and hydrogel-based 3D cell culture systems based on 3D paper-based microfluidic chips were verified to be feasible.Furthermore,by combining extrusion 3D bioprinting technology and the proposed 3D paper-based microfluidic chips,multiorgan microfluidic chips were established by directly printing 3D hydrogel structures on 3D paperbased microfluidic chips,confirming that the prepared modular 3D paper-based microfluidic chip is potentially applicable in various biomedical applications.
基金sponsored by the National Key Research and Development Program of China(2018YFA0703000)the National Natural Science Foundation of China of China(No.U1909218)the Science Fund for Creative Research Groups of the National Natural Science Foundation of China(No.T2121004).
文摘Since projection-based 3D bioprinting(PBP)could provide high resolution,it is well suited for printing delicate structures for tissue regeneration.However,the low crosslinking density and low photo-crosslinking rate of photocurable bioink make it difficult to print fine structures.Currently,an in-depth understanding of the is lacking.Here,a research framework is established for the analysis of printability during PBP.The gelatin methacryloyl(GelMA)-based bioink is used as an example,and the printability is systematically investigated.We analyze the photo-crosslinking reactions during the PBP process and summarize the specific requirements of bioinks for PBP.Two standard quantized models are established to evaluate 2D and 3D printing errors.Finally,the better strategies for bioprinting five typical structures,including solid organs,vascular structures,nerve conduits,thin-wall scaffolds,and micro needles,are presented.
基金This work was supported by the National Key Research andDevelopment Program of China(No.2018YFA0703000)the National Natural Science Foundation of China(Nos.T2121004,52235007,and 82203602)+2 种基金Zhejiang Provincial Natural Science Foundation of China under Grant No.LQ22H160020 to JWThis work was also supported by Start-up Funding of Zhejiang Provincial People’s Hospital(No.ZRY2021A001 to JW)Basic Scientific Research Funds of Department of Education of Zhejiang Province(No.KYQN202109 to JW).
文摘Prosthesis implantation and fat transplantation are common breast reconstructionmethods.In general,prosthesis implantation alone does not achieve a realistic enough appearance,and fat transplantation alone is difficult to achieve in the correct capacity.To date,no reports have focused on methods of combining fat with implanted prostheses for breast reconstruction.Using a newly designed bionic ink(i.e.,polyether F127 diacrylate(F127DA)&poly(ethylene glycol)diacrylate(PEGDA))and projection-based three-dimensional bioprinting(PBP),we report the development of a new method for printing porous prostheses.PEGDA was used to improve the printing precision of the prosthesis by increasing the gel point of F127DA and reducing the impact of external temperature.The compression modulus of the printed prosthesis was very close to that of prostheses currently used in clinical practice and to that of natural breasts.Finally,stromal vascular fraction gel(SVF-gel),a human fat extract,was injected into the pores of the synthesized prostheses to prepare a prosthesis mixed with adipose tissue.These were implanted subcutaneously in nude mice to observe their biological performance.After 14 and 28 days of observation,the prosthesis showed good biocompatibility,and adipose tissues grew well in and around the prosthesis.This result shows that a porous prosthesis containing pre-placed adipose tissues is a promising breast reconstruction material.
文摘Chromium pollution due to leaching and weathering of chromite mine overburden in mine seepage water is a serious environmental problem. In an attempt to explore the indigenous chromate resistant and reducing bacteria from chromite mine quarry seepage, 145 aerobic, heterotrophic bacteria were isolated from 14 mine seepage samples derived from chromite mines of Sukinda valley and Baula-Nuasahi belt in Orissa, India. A total of 109 isolates which were tolerant to 2 mM Cr(VI) showed different degrees of Cr(VI) reducing activ-ity in complex KSC medium and synthetic Vogel Bonner (VB) broth. Ten isolates belonging to genera like Pseudomonas, Acinetobacter, Alcaligenes, Cupriavidus and Corynebacterium were selected on the basis of their chromate reducing efficiency and it was found that they could reduce more than 50 and 75% of Cr(VI) in VB broth and KSC medium respectively. The sole Gram-positive isolate, Corynebacterium paurometabo-lum SKPD 1204 (MTCC 8730) showed maximum chromate reducing capacity in both VB broth (63.7%) and KSC medium (92%) and was capable of reducing nearly 95% of the total Cr(VI) in the mine seepage when it was grown in the mine seepage supplemented with 2% VB concentrate.
文摘Using series iteration techniques identities and apply each of these identities in we derive a number of general double series order to deduce several hypergeometric reduction formulas involving the Srivastava-Daoust double hypergeometric function. The results presented in this article are based essentially upon the hypergeometric summation theorems of Kummer and Dixon.
基金Supported by the National Natural Science Foundation of China under Grant No.11301269Jiangsu Provincial Natural Science Foundation of China under Grant No.BK20130665+2 种基金the Fundamental Research Funds KJ2013036 for the Central UniversitiesStudent Research Training under Grant No.1423A02 of Nanjing Agricultural Universitythe Research Grant RG21/2013-2014R from the Hong Kong Institute of Education
文摘In this paper, the Clarkson-Kruskal direct approach is employed to investigate the exact solutions of the 2-dimensionai rotationai Euler equations for the incompressible fluid. The application of the method leads to a system of completely solvable ordinary differential equations. Several special cases are discussed and novel nonlinear exact solutions with respect to variables x and y are obtained. It is＇of interest to notice that the pressure p is obtained by the second kind of curvilinear integral and the coefficients of the nonlinear solutions are solitary wave type functions like tanh（ kt /2 ） and sech （kt/2） due to the rotational parameter k ≠ O. Such phenomenon never appear in the classical Euler equations wherein the Coriolis force arising from the gravity and Earth＇s rotation is ignored. Finally, illustrative numerical figures are attached to show the behaviors that the exact solutions may exhibit.
文摘Si3N4 powder was synthesized by carbothermal re- duction nitridation reaction using sawdust as carbon source and introducing SiO2 by silica sol immersion. Effects of SiO2 content of silica sol, molding pressure, reaction temperature, reaction duration, and N2 flow rate on phase compositions and microstructure of result- ants were studied. The results show that using 7. 5 mass% SiO2 containing silica sol immersed sawdust as raw materials, the prepared Si3N4 powder is featured with high α-Si3N4 content, few impurities, etc. in the conditions of 1 450 ℃ of reaction temperature, 9 h of reaction duration, 400 mL ·min- 1 of N2 flow rate and 10 MPa of molding pressure.
文摘Simulation of incompressible fluid flow-elastic structure interactions is targeted by using fully-Lagrangian mesh-free computational methods. A projection-based fluid model（moving particle semi-implicit（MPS）） is coupled with either a Newtonian or a Hamiltonian Lagrangian structure model（MPS or HMPS） in a mathematically-physically consistent manner. The fluid model is founded on the solution of Navier-Stokes and continuity equations. The structure models are configured either in the framework of Newtonian mechanics on the basis of conservation of linear and angular momenta, or Hamiltonian mechanics on the basis of variational principle for incompressible elastodynamics. A set of enhanced schemes are incorporated for projection-based fluid model（Enhanced MPS）, thus, the developed coupled solvers for fluid structure interaction（FSI） are referred to as Enhanced MPS-MPS and Enhanced MPS-HMPS. Besides, two smoothed particle hydrodynamics（SPH）-based FSI solvers, being developed by the authors, are considered and their potential applicability and comparable performance are briefly discussed in comparison with MPS-based FSI solvers. The SPH-based FSI solvers are established through coupling of projection-based incompressible SPH（ISPH） fluid model and SPH-based Newtonian/Hamiltonian structure models, leading to Enhanced ISPH-SPH and Enhanced ISPH-HSPH. A comparative study is carried out on the performances of the FSI solvers through a set of benchmark tests, including hydrostatic water column on an elastic plate,high speed impact of an elastic aluminum beam, hydroelastic slamming of a marine panel and dam break with elastic gate.
基金This work was supported by the National Key Basic Research Special Funds of China (Grant No. G1999075607)the 985 Funds of Tsinghua University and the THSJZ of Tsinghua University, China.
文摘Nuclear magnetic resonance (NMR) spectros-copy has become an important tool in modern biological research. NMR spectra image analysis can be used to analyze the kinetics of biomacromolecular conformational changes. The relationship between the image parameters and the protein dynamics was investigated by using a small globular protein ω-conotoxin SO3 (ω-CTX SO3). The physical meanings of the image parameters were characterized from the results. Comparison of the data from the traditional integral area of specific resonance peaks method and the NMR image analysis method showed the advantages of using NMR spectra image analysis for kinetic analysis of two-state processes monitored by 1D proton NMR.
基金supported by the National Natural Science Foundation of China(grant numbers 11972064 and 11721202).
文摘A projection-based reduced order model(ROM)based on the Fourier collocation method is proposed for compressible flows.The incorporation of localized artificial viscosity model and filtering is pursued to enhance the robustness and accuracy of the ROM for shock-dominated flows.Furthermore,for Euler systems,ROMs built on the conservative and the skew-symmetric forms of the governing equation are compared.To ensure efficiency,the discrete empirical interpolation method(DEIM)is employed.An alternative reduction approach,exploring the sparsity of viscosity is also investigated for the viscous terms.A number of one-and two-dimensional benchmark cases are considered to test the performance of the proposed models.Results show that stable computations for shock-dominated cases can be achieved with ROMs built on both the conservative and the skew-symmetric forms without additional stabilization components other than the viscosity model and filtering.Under the same parameters,the skew-symmetric form shows better robustness and accuracy than its conservative counterpart,while the conservative form is superior in terms of efficiency.
文摘This note addresses diagnosis and performance degradation detection issues from an integrated viewpoint of functionality maintenance and cyber security of automatic control systems.It calls for more research attention on three aspects:(i)application of control and detection uni ed framework to enhancing the diagnosis capability of feedback control systems,(ii)projection-based fault detection,and complementary and explainable applications of projection-and machine learning-based techniques,and(iii)system performance degradation detection that is of elemental importance for today's automatic control systems.Some ideas and conceptual schemes are presented and illustrated by means of examples,serving as convincing arguments for research e orts in these aspects.They would contribute to the future development of capable diagnosis systems for functionality safe and cyber secure automatic control systems.
