Maximum rate of food consumption (C max) was determined for juvenile Sebastodes fuscescens (Houttuyn) at water temperature of 10, 15, 20 and 25℃. The relationships of C max to the body weight (W) at each temperature ...Maximum rate of food consumption (C max) was determined for juvenile Sebastodes fuscescens (Houttuyn) at water temperature of 10, 15, 20 and 25℃. The relationships of C max to the body weight (W) at each temperature were described by a power equation: lnC max = a + b lnW. Covariance analysis revealed significant interaction of the temperature and body weight. The relationship of adjusted C max to water temperature (T) was described by a quadratic equation: C max =-0.369 + 0.456T - 0.0117T 2. The optimal feeding temperature calculated from this equation was 19.5℃. The coefficients of the multiple regression estimation relating C max to body weight (W) and water temperature (T) were given in the Table 2.展开更多
Based on the deficiency of time convergence and variability of Web services selection for services composition supporting cross-enterprises collaboration,an algorithm QCDSS(QoS constraints of dynamic Web services sele...Based on the deficiency of time convergence and variability of Web services selection for services composition supporting cross-enterprises collaboration,an algorithm QCDSS(QoS constraints of dynamic Web services selection)to resolve dynamic Web services selection with QoS global optimal path,was proposed.The essence of the algorithm was that the problem of dynamic Web services selection with QoS global optimal path was transformed into a multi-objective services composition optimization problem with QoS constraints.The operations of the cross and mutation in genetic algorithm were brought into PSOA(particle swarm optimization algorithm),forming an improved algorithm(IPSOA)to solve the QoS global optimal problem.Theoretical analysis and experimental results indicate that the algorithm can better satisfy the time convergence requirement for Web services composition supporting cross-enterprises collaboration than the traditional algorithms.展开更多
A new trend in the development of medical image processing systems is to enhance the shar-ing of medical resources and the collaborative processing of medical specialists. This paper presents an architecture of medica...A new trend in the development of medical image processing systems is to enhance the shar-ing of medical resources and the collaborative processing of medical specialists. This paper presents an architecture of medical image dynamic collaborative processing on the distributed environment by combining the JAVA, CORBA (Common Object Request and Broker Architecture) and the MAS (Multi-Agents System) collaborative mechanism. The architecture allows medical specialists or applications to share records and cornmunicate with each other on the web by overcoming the shortcut of traditional approach using Common Gateway Interface (CGI) and client/server architecture, and can support the remote heterogeneous systems collaboration. The new approach im-proves the collaborative processing of medical data and applications and is able to enhance the in-teroperation among heterogeneous system. Research on the system will help the collaboration and cooperation among medical application systems distributed on the web, thus supply high quality medical service such as diagnosis and therapy to practicing specialists regardless of their actual geo-graphic location.展开更多
Based on a membrane-bulk coupling cell model proposed by Gomez-Marin et al. [ Phys. Rev. Lett. 98 (2007) 168303], the cooperative effects of noise and coupling on the stochastic dynamical behavior are investigated. ...Based on a membrane-bulk coupling cell model proposed by Gomez-Marin et al. [ Phys. Rev. Lett. 98 (2007) 168303], the cooperative effects of noise and coupling on the stochastic dynamical behavior are investigated. For parameters in a certain region, the oscillation can be induced by the cooperative effect of noise and coupling. Whether considering the coupling or not, corresponding coherence resonance phenomena are observed. Furthermore, the effects of two coupling parameters, cell size L and coupling intensity k, on the noise-induced oscillation of membranes are studied. Contrary effects of noise are found in and out of the deterministic oscillatory regions.展开更多
In order to improve the frequency response and anti-interference characteristics of the smart electromechanical actuator(EMA)system,and aiming at the force fighting problem when multiple actuators work synchronously,a...In order to improve the frequency response and anti-interference characteristics of the smart electromechanical actuator(EMA)system,and aiming at the force fighting problem when multiple actuators work synchronously,a multi input multi output(MIMO)position difference cross coupling control coordinated strategy based on double‑closed-loop load feedforward control is proposed and designed.In this strategy,the singular value method of return difference matrix is used to design the parameter range that meets the requirements of system stability margin,and the sensitivity function and the H_(∞)norm theory are used to design and determine the optimal solution in the obtained parameter stability region,so that the multi actuator system has excellent synchronization,stability and anti-interference.At the same time,the mathematical model of the integrated smart EMA system is established.According to the requirements of point-to-point control,the controller of double-loop control and load feedforward compensation is determined and designed to improve the frequency response and anti-interference ability of single actuator.Finally,the 270 V high-voltage smart EMA system experimental platform is built,and the frequency response,load feedforward compensation and coordinated control experiments are carried out to verify the correctness of the position difference cross coupling control strategy and the rationality of the parameter design,so that the system can reach the servo control indexes of bandwidth 6 Hz,the maximum output force 20000 N and the synchronization error≤0.1 mm,which effectively solves the problem of force fighting.展开更多
A lower-part humanoid robot CHP-1 with 12 degree-of-freedom of motion has been developed for cooperative motion,such as pushing or lifting an object.The capability of the robot is mainly dependent on the performance o...A lower-part humanoid robot CHP-1 with 12 degree-of-freedom of motion has been developed for cooperative motion,such as pushing or lifting an object.The capability of the robot is mainly dependent on the performance of the motors,thus the motors need to be properly selected.For the purpose,the kinematics of the robot was analyzed,and a number of simulations for two kinds of cooperative motions were carried out.The torques required at each motor of the robot under external forces were obtained.Here,the external forces were also estimated through simulation and literature survey.On the basis of the torques found,the selection of motors was finally suggested,and the motors are to be installed to the humanoid robot.展开更多
Based on the methods of acquaintance cache and group-based intelligent forwarding of service recommendations,a novel group-based active service(GAS) protocol for migrating workflows was proposed.This protocol did not ...Based on the methods of acquaintance cache and group-based intelligent forwarding of service recommendations,a novel group-based active service(GAS) protocol for migrating workflows was proposed.This protocol did not require service requesters to discover services or resources.The semantic acquaintance knowledge representation was exploited to describe service groups and this semantic information was used to recommend service to respective clients.The experimental results show that the new protocol proposed offers better performance than other protocols in terms of first-response-time,success-scope and ratio of success-packet-number to total-packet-number.When the number of service request packet is 20,the first-response-time of GAS protocol is only 5.1 s,which is significantly lower than that of other protocols.The success-scope of GAS protocol is 49.1%,showing that GAS protocol can effectively improve the reliability of mobile transactions.And the ratio of success-packet-number to total-packet-number of GAS protocol is up to 0.080,which is obviously higher than that of other protocols.展开更多
In this paper, we first overview some traditional relaying technologies, and then present a Network Coding-Aware Cooperative Relaying (NC2R) scheme to improve the performance of downlink transmission for relayaided ...In this paper, we first overview some traditional relaying technologies, and then present a Network Coding-Aware Cooperative Relaying (NC2R) scheme to improve the performance of downlink transmission for relayaided cellular networks. Moreover, systematic performance analysis and extensive simulations are performed for the proposed NC2R and traditional relaying and non-relaying schemes. The results show that NCR outperforms conventional relaying and non-relaying schemes in terms of blocking probability and spectral efficiency, especially for cell-edge users. Additionally, the location selections for relays with NCR are also discussed. These results will provide some insights for incorporating network coding into next-generation broadband cellular relay mobile systems.展开更多
The mobility of relay has great influence on the performance of a cooperative relay system.This paper proposes a dynamic selection scheme under the amplify-and-forward communication mode in high mobility environment,b...The mobility of relay has great influence on the performance of a cooperative relay system.This paper proposes a dynamic selection scheme under the amplify-and-forward communication mode in high mobility environment,based on the estimation of channels and the power allocation for each relay node by comparing it with the pre-set threshold.This scheme is used to choose the cooperative relay dynamically for a multiple relay scenario.Simulation results show that this proposed relay selection scheme decreases the outage probability effectively,maintains system capacity well,and improves the performance of the relay system.展开更多
The topic of this paper is animals in painting and the investigative process undertaken by the artist Vanessa Barbay during her practice--led Ph.D.. Her aim was to discover a way to present deceased animals that retai...The topic of this paper is animals in painting and the investigative process undertaken by the artist Vanessa Barbay during her practice--led Ph.D.. Her aim was to discover a way to present deceased animals that retained their agency as individuals by challenging the objectifying nature of representation. The foundation of this method was the collaboration between artist and dead animal subjects through harnessing the natural decomposition of the subject in order to generate their image. A related stream of Barbay's research was learning about the art and culture of Kunwinjku speaking artists living in Kunbarlanja Western Amhem Land where artists have painted images of animals on rock shelters and on bark from ancient through to contemporary times. The significance of their form of animal representation is a mythopoeic relationship between locally found pigments and animal bodies. Paintings are considered as collaboration between matter, subject, and artist, which Barbay extends in her current work centred on collaborative painting involving more than one artist.展开更多
[Objective]This study was conducted to obtain a new high-efficiency acaricide mixture.[Method]The synergism acaricidal of diafenthiuron and fenbutatin-oxide against carmine spider mite was investigated,and the optimal...[Objective]This study was conducted to obtain a new high-efficiency acaricide mixture.[Method]The synergism acaricidal of diafenthiuron and fenbutatin-oxide against carmine spider mite was investigated,and the optimal ratio of both acaricides were determined by means of co-toxicity factors and co-toxicity coefficients(CTC).[Result]At 24 h post-treatment,the LC50values of diafenthiuron and fenbutatin-oxide against T.cinnabarinus female adults were 154.67 and 93.26 mg/L,respectively,and the synergistic mass ratios of diafenthiuron and fenbutatin-oxide ranged from 1:0.06 to 1:0.87,and the optimal diafenthiuron-to-fenbutatin-oxide ratio was 1:0.39 with the LC50and CTC of 67.87 mg/L and 188.93(CTC significantly above 100 strongly indicated synergism),respectively,and the toxicity relative to diafenthiuron and fenbutatin-oxide was 2.28 and 1.37 times,respectively.[Conclusion]The joint acaricidal action of diafenthiuron and fenbutatin-oxide strongly indicates synergism.These findings proved scientific theoretical basis for mixing diafenthiuron and fenbutatin-oxide to control spider mites and developing a new synergisic acaricide.展开更多
Periodic whole cross-section computation models are established for segmental baffle heat exchanger, shutter baffle heat exchanger, and trapezoid-like tilted baffle heat exchanger. The reliability of models is verifie...Periodic whole cross-section computation models are established for segmental baffle heat exchanger, shutter baffle heat exchanger, and trapezoid-like tilted baffle heat exchanger. The reliability of models is verified by comparing the simulated results to the results obtained from the Bell-Delaware method. Due to the orthogonal assembly of the baffles, the shell side fluid shows the twisty flow of trapezoid-like tilted baffle heat exchanger. The essential mechanism on disturbing flow and heat transfer enhancement is revealed by defining the non-dimensional factor η of the shell side fluid flow direction of heat exchanger and the field synergy principle. The results show that at the same Reynolds number, the shell side fluid convection heat transfer coefficient of trapezoid-like tilted baffle heat exchanger is 12.43%-24.33% and 6.71%-11.51% higher than those of segmental baffle heat exchanger and shutter baffle heat exchanger, respectively. The shell side fluid flow velocity field and the pressure gradient field of trapezoid-like tilted baffle heat exchanger and shutter baffle heat exchanger decreases compared with that of segmental baffle heat exchanger, so the shell side fluid flow resistance and pressure drop is increased; the shell side comprehensive performance of trapezoid-like tilted baffle heat exchanger is 5.85%-9.06% higher than that of segmental baffle heat exchanger, and 15.27%-23.28% higher than that of shutter baffle heat exchanger. In this study, a baffle structure with higher efficiency of the energy utilization for the heat exchanger is provided.展开更多
The problem of strategic stability of long-range cooperative agreements in dynamic games with coalition structures is investigated. Based on imputation distribution procedures, a general theoretical framework of the d...The problem of strategic stability of long-range cooperative agreements in dynamic games with coalition structures is investigated. Based on imputation distribution procedures, a general theoretical framework of the differential game with a coalition structure is proposed. A few assumptions about the deviation instant for a coalition are made concerning the behavior of a group of many individuals in certain dynamic environments.From these, the time-consistent cooperative agreement can be strategically supported by ε-Nash or strong ε-Nash equilibria. While in games in the extensive form with perfect information, it is somewhat surprising that without the assumptions of deviation instant for a coalition, Nash or strong Nash equilibria can be constructed.展开更多
The differentiation status of neuroblastoma (NB) strongly correlates with its clinical outcomes; however, the molecular mechanisms driving maintenance of sternness and differentiation remain poorly understood. Here,...The differentiation status of neuroblastoma (NB) strongly correlates with its clinical outcomes; however, the molecular mechanisms driving maintenance of sternness and differentiation remain poorly understood. Here, we show that plant homeodomain finger-containing protein 20 (PHF20) functions as a critical epigenetic regulator in sustaining stem cell-like phenotype of NB by using CRISPR/Casg-based targeted knockout (KO) for high-throughput screening of gene function in NB cell differentiation. The expression of PHF20 in NB was significantly associated with high aggressiveness of the tumor and poor outcomes for NB patients. Deletion of PHF20 inhibited NB cell proliferation, invasive migration, and stem ceU-Uke traits. Mechanistically, PHF20 interacts with poly(ADP-ribose) polymerase 1 (PARP1) and directly binds to promoter regions of octamer-binding transcription factor 4 (OCT4) and sex determining region Y-box 2 (SOX2) to modulate a histone mark associated with active transcription, trimethylation of lysine 4 on histone H3 protein subunit (H3K4me3). Overexpression of OCT4 and SOX2 restored growth and progression of PHF20 KO tumor cells. Consistently, OCT4 and SOX2 protein levels in clinical NB specimens were positively correlated with PHF20 expression. Our results establish PHF20 as a key driver of NB stem cell-like properties and aggressive behaviors, with implications for prognosis and therapy.展开更多
Geomicrobiology is a sub-discipline of geobiology and emphasizes the interaction between microorganisms and their environment on Earth. There is a need to explicitly emphasize the biogeochemical processes performed by...Geomicrobiology is a sub-discipline of geobiology and emphasizes the interaction between microorganisms and their environment on Earth. There is a need to explicitly emphasize the biogeochemical processes performed by microorganisms associated with Earth's tectonic activities, especially under the framework of the modern theory of plate tectonics. Tectonomicrobiology aims to create a better synergy between microbial and active tectonic processes. This explicit synergy should also foster better communications between solid Earth scientists and life scientists in terms of holistic Earth system dynamics at both tectonic and micro-scales.展开更多
文摘Maximum rate of food consumption (C max) was determined for juvenile Sebastodes fuscescens (Houttuyn) at water temperature of 10, 15, 20 and 25℃. The relationships of C max to the body weight (W) at each temperature were described by a power equation: lnC max = a + b lnW. Covariance analysis revealed significant interaction of the temperature and body weight. The relationship of adjusted C max to water temperature (T) was described by a quadratic equation: C max =-0.369 + 0.456T - 0.0117T 2. The optimal feeding temperature calculated from this equation was 19.5℃. The coefficients of the multiple regression estimation relating C max to body weight (W) and water temperature (T) were given in the Table 2.
基金Project(70631004)supported by the Key Project of the National Natural Science Foundation of ChinaProject(20080440988)supported by the Postdoctoral Science Foundation of China+1 种基金Project(09JJ4030)supported by the Natural Science Foundation of Hunan Province,ChinaProject supported by the Postdoctoral Science Foundation of Central South University,China
文摘Based on the deficiency of time convergence and variability of Web services selection for services composition supporting cross-enterprises collaboration,an algorithm QCDSS(QoS constraints of dynamic Web services selection)to resolve dynamic Web services selection with QoS global optimal path,was proposed.The essence of the algorithm was that the problem of dynamic Web services selection with QoS global optimal path was transformed into a multi-objective services composition optimization problem with QoS constraints.The operations of the cross and mutation in genetic algorithm were brought into PSOA(particle swarm optimization algorithm),forming an improved algorithm(IPSOA)to solve the QoS global optimal problem.Theoretical analysis and experimental results indicate that the algorithm can better satisfy the time convergence requirement for Web services composition supporting cross-enterprises collaboration than the traditional algorithms.
基金the National Nature Science Foundation of China.
文摘A new trend in the development of medical image processing systems is to enhance the shar-ing of medical resources and the collaborative processing of medical specialists. This paper presents an architecture of medical image dynamic collaborative processing on the distributed environment by combining the JAVA, CORBA (Common Object Request and Broker Architecture) and the MAS (Multi-Agents System) collaborative mechanism. The architecture allows medical specialists or applications to share records and cornmunicate with each other on the web by overcoming the shortcut of traditional approach using Common Gateway Interface (CGI) and client/server architecture, and can support the remote heterogeneous systems collaboration. The new approach im-proves the collaborative processing of medical data and applications and is able to enhance the in-teroperation among heterogeneous system. Research on the system will help the collaboration and cooperation among medical application systems distributed on the web, thus supply high quality medical service such as diagnosis and therapy to practicing specialists regardless of their actual geo-graphic location.
基金supported by the National Natural Science Foundation of China under Grant No.10575041
文摘Based on a membrane-bulk coupling cell model proposed by Gomez-Marin et al. [ Phys. Rev. Lett. 98 (2007) 168303], the cooperative effects of noise and coupling on the stochastic dynamical behavior are investigated. For parameters in a certain region, the oscillation can be induced by the cooperative effect of noise and coupling. Whether considering the coupling or not, corresponding coherence resonance phenomena are observed. Furthermore, the effects of two coupling parameters, cell size L and coupling intensity k, on the noise-induced oscillation of membranes are studied. Contrary effects of noise are found in and out of the deterministic oscillatory regions.
基金supported by the National Natural Science Foundation of China(No.52077100)the Aviation Science Foundation(No.201958052001)
文摘In order to improve the frequency response and anti-interference characteristics of the smart electromechanical actuator(EMA)system,and aiming at the force fighting problem when multiple actuators work synchronously,a multi input multi output(MIMO)position difference cross coupling control coordinated strategy based on double‑closed-loop load feedforward control is proposed and designed.In this strategy,the singular value method of return difference matrix is used to design the parameter range that meets the requirements of system stability margin,and the sensitivity function and the H_(∞)norm theory are used to design and determine the optimal solution in the obtained parameter stability region,so that the multi actuator system has excellent synchronization,stability and anti-interference.At the same time,the mathematical model of the integrated smart EMA system is established.According to the requirements of point-to-point control,the controller of double-loop control and load feedforward compensation is determined and designed to improve the frequency response and anti-interference ability of single actuator.Finally,the 270 V high-voltage smart EMA system experimental platform is built,and the frequency response,load feedforward compensation and coordinated control experiments are carried out to verify the correctness of the position difference cross coupling control strategy and the rationality of the parameter design,so that the system can reach the servo control indexes of bandwidth 6 Hz,the maximum output force 20000 N and the synchronization error≤0.1 mm,which effectively solves the problem of force fighting.
基金Project supported by the Second Stage of Brain Korea 21 Projects
文摘A lower-part humanoid robot CHP-1 with 12 degree-of-freedom of motion has been developed for cooperative motion,such as pushing or lifting an object.The capability of the robot is mainly dependent on the performance of the motors,thus the motors need to be properly selected.For the purpose,the kinematics of the robot was analyzed,and a number of simulations for two kinds of cooperative motions were carried out.The torques required at each motor of the robot under external forces were obtained.Here,the external forces were also estimated through simulation and literature survey.On the basis of the torques found,the selection of motors was finally suggested,and the motors are to be installed to the humanoid robot.
基金Project(60573169) supported by the National Natural Science Foundation of China
文摘Based on the methods of acquaintance cache and group-based intelligent forwarding of service recommendations,a novel group-based active service(GAS) protocol for migrating workflows was proposed.This protocol did not require service requesters to discover services or resources.The semantic acquaintance knowledge representation was exploited to describe service groups and this semantic information was used to recommend service to respective clients.The experimental results show that the new protocol proposed offers better performance than other protocols in terms of first-response-time,success-scope and ratio of success-packet-number to total-packet-number.When the number of service request packet is 20,the first-response-time of GAS protocol is only 5.1 s,which is significantly lower than that of other protocols.The success-scope of GAS protocol is 49.1%,showing that GAS protocol can effectively improve the reliability of mobile transactions.And the ratio of success-packet-number to total-packet-number of GAS protocol is up to 0.080,which is obviously higher than that of other protocols.
基金supported by the State Key Laboratory of Rail Traffic Control and Safety,Beijing Jiaotong University under Grant No.RCS2012ZT008the National Key Basic Research Program of China(973Program)under Grant No.2012CB316100(2)+1 种基金the National Natural Science Foundation of China under Grants No.61201203,No.61171064the Fundamental Research Funds for the Central Universities under Grant No.2012JBM030
文摘In this paper, we first overview some traditional relaying technologies, and then present a Network Coding-Aware Cooperative Relaying (NC2R) scheme to improve the performance of downlink transmission for relayaided cellular networks. Moreover, systematic performance analysis and extensive simulations are performed for the proposed NC2R and traditional relaying and non-relaying schemes. The results show that NCR outperforms conventional relaying and non-relaying schemes in terms of blocking probability and spectral efficiency, especially for cell-edge users. Additionally, the location selections for relays with NCR are also discussed. These results will provide some insights for incorporating network coding into next-generation broadband cellular relay mobile systems.
基金Supported by the National Natural Science Foundation of China(No.61172073)the State Key Laboratory of Rail Traffic Control and Safety,Beijing Jiaotong University(No.RCS2011ZT003)+2 种基金the Open Research Fund of National Mobile Communications Research Laboratory,Southeast University(No.2012D19)the Fundamental Research Funds for the Central Universities of Ministry of Education of China(No.2013JBZ001)the Program for New Century Excellent Talents in University of Ministry of Education of China(No.NCET-12-0766)
文摘The mobility of relay has great influence on the performance of a cooperative relay system.This paper proposes a dynamic selection scheme under the amplify-and-forward communication mode in high mobility environment,based on the estimation of channels and the power allocation for each relay node by comparing it with the pre-set threshold.This scheme is used to choose the cooperative relay dynamically for a multiple relay scenario.Simulation results show that this proposed relay selection scheme decreases the outage probability effectively,maintains system capacity well,and improves the performance of the relay system.
文摘The topic of this paper is animals in painting and the investigative process undertaken by the artist Vanessa Barbay during her practice--led Ph.D.. Her aim was to discover a way to present deceased animals that retained their agency as individuals by challenging the objectifying nature of representation. The foundation of this method was the collaboration between artist and dead animal subjects through harnessing the natural decomposition of the subject in order to generate their image. A related stream of Barbay's research was learning about the art and culture of Kunwinjku speaking artists living in Kunbarlanja Western Amhem Land where artists have painted images of animals on rock shelters and on bark from ancient through to contemporary times. The significance of their form of animal representation is a mythopoeic relationship between locally found pigments and animal bodies. Paintings are considered as collaboration between matter, subject, and artist, which Barbay extends in her current work centred on collaborative painting involving more than one artist.
基金Supported by National Natural Science Foundation of China(31201546)Earmarked Fund for China Agriculture Research System(CARS-22-SYZ27)the Innovation Fund of Young Scholars in Institute of Sericulture&Apiculture,Yunnan Academy of Agricultural Sciences(QC2014003)
文摘[Objective]This study was conducted to obtain a new high-efficiency acaricide mixture.[Method]The synergism acaricidal of diafenthiuron and fenbutatin-oxide against carmine spider mite was investigated,and the optimal ratio of both acaricides were determined by means of co-toxicity factors and co-toxicity coefficients(CTC).[Result]At 24 h post-treatment,the LC50values of diafenthiuron and fenbutatin-oxide against T.cinnabarinus female adults were 154.67 and 93.26 mg/L,respectively,and the synergistic mass ratios of diafenthiuron and fenbutatin-oxide ranged from 1:0.06 to 1:0.87,and the optimal diafenthiuron-to-fenbutatin-oxide ratio was 1:0.39 with the LC50and CTC of 67.87 mg/L and 188.93(CTC significantly above 100 strongly indicated synergism),respectively,and the toxicity relative to diafenthiuron and fenbutatin-oxide was 2.28 and 1.37 times,respectively.[Conclusion]The joint acaricidal action of diafenthiuron and fenbutatin-oxide strongly indicates synergism.These findings proved scientific theoretical basis for mixing diafenthiuron and fenbutatin-oxide to control spider mites and developing a new synergisic acaricide.
基金financially supported by the National Natural Science Foundation of China (Grant No. 21776263, No. 51006092, No. 51776190, No. 51476147)the Henan Province Science and Technology Breakthrough Plan of China (Grant No. 182102310022)the Applied Research Plan of Key Scientific Research Projects of Henan Province Higher Education of China (Grant No. 18A470001, No. 17A530006)
文摘Periodic whole cross-section computation models are established for segmental baffle heat exchanger, shutter baffle heat exchanger, and trapezoid-like tilted baffle heat exchanger. The reliability of models is verified by comparing the simulated results to the results obtained from the Bell-Delaware method. Due to the orthogonal assembly of the baffles, the shell side fluid shows the twisty flow of trapezoid-like tilted baffle heat exchanger. The essential mechanism on disturbing flow and heat transfer enhancement is revealed by defining the non-dimensional factor η of the shell side fluid flow direction of heat exchanger and the field synergy principle. The results show that at the same Reynolds number, the shell side fluid convection heat transfer coefficient of trapezoid-like tilted baffle heat exchanger is 12.43%-24.33% and 6.71%-11.51% higher than those of segmental baffle heat exchanger and shutter baffle heat exchanger, respectively. The shell side fluid flow velocity field and the pressure gradient field of trapezoid-like tilted baffle heat exchanger and shutter baffle heat exchanger decreases compared with that of segmental baffle heat exchanger, so the shell side fluid flow resistance and pressure drop is increased; the shell side comprehensive performance of trapezoid-like tilted baffle heat exchanger is 5.85%-9.06% higher than that of segmental baffle heat exchanger, and 15.27%-23.28% higher than that of shutter baffle heat exchanger. In this study, a baffle structure with higher efficiency of the energy utilization for the heat exchanger is provided.
基金supported by National Natural Science Foundation of China(Grant Nos.7117112071373262 and 71571108)+3 种基金Projects of International(Regional)Cooperation and Exchanges of National Natural Science Foundation of China(Grant No.71411130215)Specialized Research Fund for the Doctoral Program of Higher Education of China(Grant No.20133706110002)Natural Science Foundation of Shandong Province of China(Grant No.ZR2015GZ007)Saint Petersburg State University(Grant No.9.38.245.2014)
文摘The problem of strategic stability of long-range cooperative agreements in dynamic games with coalition structures is investigated. Based on imputation distribution procedures, a general theoretical framework of the differential game with a coalition structure is proposed. A few assumptions about the deviation instant for a coalition are made concerning the behavior of a group of many individuals in certain dynamic environments.From these, the time-consistent cooperative agreement can be strategically supported by ε-Nash or strong ε-Nash equilibria. While in games in the extensive form with perfect information, it is somewhat surprising that without the assumptions of deviation instant for a coalition, Nash or strong Nash equilibria can be constructed.
基金This work was supported by grants from the National Natural Science Foundation of China (81572766 and 31771630), the National Key Research and Development Program of China (2017YFA0103800), Guangdong Innovative and Entrepreneurial Research Team Program (2016ZT06S029), Guangdong Natural Science Foundation (2016A030313215 and 2016A030313238), SYSU Young Teachers Training Program (16YKZD14) and grants (CA101795 and IU54CA210181) from U.S. National Cancer Institute, National Institutes of Health (NIH), DOD (W81XWH-16- 1-0417), and CPRIT (DP150099, RP170537, and RP150611).
文摘The differentiation status of neuroblastoma (NB) strongly correlates with its clinical outcomes; however, the molecular mechanisms driving maintenance of sternness and differentiation remain poorly understood. Here, we show that plant homeodomain finger-containing protein 20 (PHF20) functions as a critical epigenetic regulator in sustaining stem cell-like phenotype of NB by using CRISPR/Casg-based targeted knockout (KO) for high-throughput screening of gene function in NB cell differentiation. The expression of PHF20 in NB was significantly associated with high aggressiveness of the tumor and poor outcomes for NB patients. Deletion of PHF20 inhibited NB cell proliferation, invasive migration, and stem ceU-Uke traits. Mechanistically, PHF20 interacts with poly(ADP-ribose) polymerase 1 (PARP1) and directly binds to promoter regions of octamer-binding transcription factor 4 (OCT4) and sex determining region Y-box 2 (SOX2) to modulate a histone mark associated with active transcription, trimethylation of lysine 4 on histone H3 protein subunit (H3K4me3). Overexpression of OCT4 and SOX2 restored growth and progression of PHF20 KO tumor cells. Consistently, OCT4 and SOX2 protein levels in clinical NB specimens were positively correlated with PHF20 expression. Our results establish PHF20 as a key driver of NB stem cell-like properties and aggressive behaviors, with implications for prognosis and therapy.
基金supported by the National Natural Science Foundation of China(Grant Nos.41530105,41373072,91628301&U1606401)the Chinese Academy of Sciences(Grant Nos.Y4SL021001&QYZDY-SSW-DQC005)the Southern University of Science and Technology(Grant No.Y01316209)
文摘Geomicrobiology is a sub-discipline of geobiology and emphasizes the interaction between microorganisms and their environment on Earth. There is a need to explicitly emphasize the biogeochemical processes performed by microorganisms associated with Earth's tectonic activities, especially under the framework of the modern theory of plate tectonics. Tectonomicrobiology aims to create a better synergy between microbial and active tectonic processes. This explicit synergy should also foster better communications between solid Earth scientists and life scientists in terms of holistic Earth system dynamics at both tectonic and micro-scales.