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Use of supervised and unsupervised approaches to make zonal application maps for variable-rate application of crop growth regulators in commercial cotton fields
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作者 ANDREA Maria C.da S. OLIVEIRA Cristiano F.de +7 位作者 MOTA Fabrícia C.M. SANTOS Rafael C.dos RODRIGUES JUNIOR Edilson F. BIANCHI Lucas M. OLIVEIRA Rodrigo S.de GOUVEIA Caio M.de BARBOSA Victor G.S. BISPO E SILVA Marco A. 《Journal of Cotton Research》 2025年第1期1-20,共20页
Background Zonal application maps are designed to represent field variability using key variables that can be translated into tailored management practices.For cotton,zonal maps for crop growth regulator(CGR)applicati... Background Zonal application maps are designed to represent field variability using key variables that can be translated into tailored management practices.For cotton,zonal maps for crop growth regulator(CGR)applications under variable-rate(VR)strategies are commonly based exclusively on vegetation indices(VIs)variability.However,VIs often saturate in dense crop vegetation areas,limiting their effectiveness in distinguishing variability in crop growth.This study aimed to compare unsupervised framework(UF)and supervised framework(SUF)approaches for generat-ing zonal application maps for CGR under VR conditions.During 2022-2023 agricultural seasons,an UF was employed to generate zonal maps based on locally collected field data on plant height of cotton,satellite imagery,soil texture,and phenology data.Subsequently,a SUF(based on historical data between 2020-2021 to 2022-2023 agricultural seasons)was developed to predict plant height using remote sensing and phenology data,aiming to replicate same zonal maps but without relying on direct field measurements of plant height.Both approaches were tested in three fields and on two different dates per field.Results The predictive model for plant height of SUF performed well,as indicated by the model metrics.However,when comparing zonal application maps for specific field-date combinations,the predicted plant height exhibited lower variability compared with field measurements.This led to variable compatibility between SUF maps,which utilized the model predictions,and the UF maps,which were based on the real field data.Fields characterized by much pronounced soil texture variability yielded the highest compatibility between the zonal application maps produced by both SUF and UF approaches.This was predominantly due to the greater consistency in estimating plant development patterns within these heterogeneous field environments.While VR application approach can facilitate product savings during the application operation,other key factors must be considered.These include the availability of specialized machinery required for this type of applications,as well as the inherent operational costs associated with applying a single CGR product which differs from the typical uniform rate applications that often integrate multi-ple inputs.Conclusion Predictive modeling shows promise for assisting in the creation of zonal application maps for VR of CGR applications.However,the degree of agreement with the actual variability in crop growth found in the field should be evaluated on a field-by-field basis.The SUF approach,which is based on plant heigh prediction,demonstrated potential for supporting the development of zonal application maps for VR of CGR applications.However,the degree to which this approach aligns itself with the actual variability in crop growth observed in the field may vary,necessi-tating field-by-field evaluation. 展开更多
关键词 Cotton Site-specific management Crop growth regulator Unsupervised framework Supervised framework Zonal application maps
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An overview of pigment gland morphogenesis and its regulatory mechanism
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作者 SUN Yue YANG Ping +5 位作者 HAN Yifei LI Huazu SUN Deli CHEN Jinhong ZHU Shuijin ZHAO Tianlun 《Journal of Cotton Research》 CAS 2024年第2期207-214,共8页
Cotton has enormous economic potential,providing high-quality protein,oil,and fibre.But the comprehensive utilization of cottonseed is limited by the presence of pigment gland and its inclusion.Pigment gland is a comm... Cotton has enormous economic potential,providing high-quality protein,oil,and fibre.But the comprehensive utilization of cottonseed is limited by the presence of pigment gland and its inclusion.Pigment gland is a common characteristic of Gossypium genus and its relatives,appearing as visible dark opaque dots in most tissues and organs of cotton plants.Secondary metabolites,such as gossypol,synthesized and stored in the cavities of pigment glands act as natural phytoalexins,but are toxic to humans and other monogastric animals.However,only a few cotton genes have been identified as being associated with pigment gland morphogenesis to date,and the developmental processes and regulatory mechanism involved in pigment gland formation remain largely unclear.Here,the research progress on the process of pigment gland morphogenesis and the genetic basis of cotton pigment glands is reviewed,for providing a theoretical basis for cultivating cotton with the ideal pigment gland trait. 展开更多
关键词 Cotton Pigment gland morphogenesis Transcriptional regulation Terpenoids biosynthesis
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Self-adaptive learning based discrete differential evolution algorithm for solving CJWTA problem 被引量:6
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作者 Yu Xue Yi Zhuang +2 位作者 Tianquan Ni Siru Ni Xuezhi Wen 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2014年第1期59-68,共10页
Cooperative jamming weapon-target assignment (CJWTA) problem is a key issue in electronic countermeasures (ECM). Some symbols which relevant to the CJWTA are defined firstly. Then, a formulation of jamming fitness... Cooperative jamming weapon-target assignment (CJWTA) problem is a key issue in electronic countermeasures (ECM). Some symbols which relevant to the CJWTA are defined firstly. Then, a formulation of jamming fitness is presented. Final y, a model of the CJWTA problem is constructed. In order to solve the CJWTA problem efficiently, a self-adaptive learning based discrete differential evolution (SLDDE) algorithm is proposed by introduc-ing a self-adaptive learning mechanism into the traditional discrete differential evolution algorithm. The SLDDE algorithm steers four candidate solution generation strategies simultaneously in the framework of the self-adaptive learning mechanism. Computa-tional simulations are conducted on ten test instances of CJWTA problem. The experimental results demonstrate that the proposed SLDDE algorithm not only can generate better results than only one strategy based discrete differential algorithms, but also outper-forms two algorithms which are proposed recently for the weapon-target assignment problems. 展开更多
关键词 global optimization self-adaptive discrete differentialevolution weapon-target assignment (WTA) cooperative jamming.
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Self-adaptive PID controller of microwave drying rotary device tuning on-line by genetic algorithms 被引量:6
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作者 杨彪 梁贵安 +5 位作者 彭金辉 郭胜惠 李玮 张世敏 李英伟 白松 《Journal of Central South University》 SCIE EI CAS 2013年第10期2685-2692,共8页
The control design, based on self-adaptive PID with genetic algorithms(GA) tuning on-line was investigated, for the temperature control of industrial microwave drying rotary device with the multi-layer(IMDRDWM) and wi... The control design, based on self-adaptive PID with genetic algorithms(GA) tuning on-line was investigated, for the temperature control of industrial microwave drying rotary device with the multi-layer(IMDRDWM) and with multivariable nonlinear interaction of microwave and materials. The conventional PID control strategy incorporated with optimization GA was put forward to maintain the optimum drying temperature in order to keep the moisture content below 1%, whose adaptation ability included the cost function of optimization GA according to the output change. Simulations on five different industrial process models and practical temperature process control system for selenium-enriched slag drying intensively by using IMDRDWM were carried out systematically, indicating the reliability and effectiveness of control design. The parameters of proposed control design are all on-line implemented without iterative predictive calculations, and the closed-loop system stability is guaranteed, which makes the developed scheme simpler in its synthesis and application, providing the practical guidelines for the control implementation and the parameter design. 展开更多
关键词 industrial microwave DRYING ROTARY device self-adaptive PID controller genetic algorithm ON-LINE tuning SELENIUM-ENRICHED SLAG
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Acid-pickling plates and strips speed control system by microwave heating based on self-adaptive fuzzy PID algorithm 被引量:7
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作者 杨彪 彭金辉 +3 位作者 郭胜惠 张世敏 李玮 何涛 《Journal of Central South University》 SCIE EI CAS 2012年第8期2179-2186,共8页
Double self-adaptive fuzzy PID algorithm-based control strategy was proposed to construct quasi-cascade control system to control the speed of the acid-pickling process of titanium plates and strips. It is very useful... Double self-adaptive fuzzy PID algorithm-based control strategy was proposed to construct quasi-cascade control system to control the speed of the acid-pickling process of titanium plates and strips. It is very useful in overcoming non-linear dynamic behavior, uncertain and time-varying parameters, un-modeled dynamics, and couples between the automatic turbulence control (ATC) and the automatic acid temperature control (AATC) with varying parameters during the operation process. The quasi-cascade control system of inner and outer loop self-adaptive fuzzy PID controller was built, which could effectively control the pickling speed of plates and strips. The simulated results and real application indicate that the plates and strips acid pickling speed control system has good performances of adaptively tracking the parameter variations and anti-disturbances, which ensures the match of acid pickling temperature and turbulence of flowing with acid pickling speed, improving the surface quality of plates and strips acid pickling, and energy efficiency. 展开更多
关键词 self-adaptive fuzzy PID algorithm microwave heating acid pickling plates and strips mixed-acid media
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An algorithm to remove noise from locomotive bearing vibration signal based on self-adaptive EEMD filter 被引量:4
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作者 王春生 沙春阳 +1 位作者 粟梅 胡玉坤 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第2期478-488,共11页
An improved ensemble empirical mode decomposition(EEMD) algorithm is described in this work, in which the sifting and ensemble number are self-adaptive. In particular, the new algorithm can effectively avoid the mode ... An improved ensemble empirical mode decomposition(EEMD) algorithm is described in this work, in which the sifting and ensemble number are self-adaptive. In particular, the new algorithm can effectively avoid the mode mixing problem. The algorithm has been validated with a simulation signal and locomotive bearing vibration signal. The results show that the proposed self-adaptive EEMD algorithm has a better filtering performance compared with the conventional EEMD. The filter results further show that the feature of the signal can be distinguished clearly with the proposed algorithm, which implies that the fault characteristics of the locomotive bearing can be detected successfully. 展开更多
关键词 locomotive bearing vibration signal enhancement self-adaptive EEMD parameter-varying noise signal feature extraction
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An improved self-adaptive membrane computing optimization algorithm and its applications in residue hydrogenating model parameter estimation 被引量:1
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作者 芦会彬 薄翠梅 杨世品 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第10期3909-3915,共7页
In order to solve the non-linear and high-dimensional optimization problems more effectively, an improved self-adaptive membrane computing(ISMC) optimization algorithm was proposed. The proposed ISMC algorithm applied... In order to solve the non-linear and high-dimensional optimization problems more effectively, an improved self-adaptive membrane computing(ISMC) optimization algorithm was proposed. The proposed ISMC algorithm applied improved self-adaptive crossover and mutation formulae that can provide appropriate crossover operator and mutation operator based on different functions of the objects and the number of iterations. The performance of ISMC was tested by the benchmark functions. The simulation results for residue hydrogenating kinetics model parameter estimation show that the proposed method is superior to the traditional intelligent algorithms in terms of convergence accuracy and stability in solving the complex parameter optimization problems. 展开更多
关键词 optimization algorithm membrane computing benchmark function improved self-adaptive operator
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An improved de-interleaving algorithm of radar pulses based on SOFM with self-adaptive network topology 被引量:2
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作者 JIANG Wen FU Xiongjun +1 位作者 CHANG Jiayun QIN Rui 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2020年第4期712-721,共10页
As a core part of the electronic warfare(EW) system,de-interleaving is used to separate interleaved radar signals. As interleaved radar pulses become more complex and denser, intelligent classification of radar signal... As a core part of the electronic warfare(EW) system,de-interleaving is used to separate interleaved radar signals. As interleaved radar pulses become more complex and denser, intelligent classification of radar signals has become very important. The self-organizing feature map(SOFM) is an excellent artificial neural network, which has huge advantages in intelligent classification of complex data. However, the de-interleaving process based on SOFM is faced with the problems that the initialization of the map size relies on prior information and the network topology cannot be adaptively adjusted. In this paper, an SOFM with self-adaptive network topology(SANT-SOFM) algorithm is proposed to solve the above problems. The SANT-SOFM algorithm first proposes an adaptive proliferation algorithm to adjust the map size, so that the initialization of the map size is no longer dependent on prior information but is gradually adjusted with the input data. Then,structural optimization algorithms are proposed to gradually optimize the topology of the SOFM network in the iterative process,constructing an optimal SANT. Finally, the optimized SOFM network is used for de-interleaving radar signals. Simulation results show that SANT-SOFM could get excellent performance in complex EW environments and the probability of getting the optimal map size is over 95% in the absence of priori information. 展开更多
关键词 de-interleaving self-organizing feature map(SOFM) self-adaptive network topology(SANT)
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Research on DSP-Based Automatic Excitation Regulator in Small Rural Hydropower Station 被引量:1
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作者 Gu Xiang-yu Zhao Yu-lin +2 位作者 Fu Yan Zhang Yu-juan Sun Shuai 《Journal of Northeast Agricultural University(English Edition)》 CAS 2013年第1期65-69,共5页
Excitation regulator has played an important role to ensure that generator run safely and stably. However, in some remote areas, the rural small generator excitation control system is very backward, and it has hindere... Excitation regulator has played an important role to ensure that generator run safely and stably. However, in some remote areas, the rural small generator excitation control system is very backward, and it has hindered the development of Chinese agriculture and the pace of new countryside construction. This paper introduced a kind of structure and basic principle of DSP-based automatic excitation regulator, which was applied to rural small generator. We chose TMS320LF2407A chip as the core of regulator control system; the regulator adjusted PWM based on PID control strategy to control the exciting current. The theoretical analysis showed that the regulator had the characteristics of simplicity and reliability, well dynamic and static characteristics, and it could also adjust its own state quickly. The result was applicable to small rural hydropower station. 展开更多
关键词 DSP PID control strategy automatic excitation regulator new countryside construction
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Enhanced self-adaptive evolutionary algorithm for numerical optimization 被引量:1
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作者 Yu Xue YiZhuang +2 位作者 Tianquan Ni Jian Ouyang ZhouWang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2012年第6期921-928,共8页
There are many population-based stochastic search algorithms for solving optimization problems. However, the universality and robustness of these algorithms are still unsatisfactory. This paper proposes an enhanced se... There are many population-based stochastic search algorithms for solving optimization problems. However, the universality and robustness of these algorithms are still unsatisfactory. This paper proposes an enhanced self-adaptiveevolutionary algorithm (ESEA) to overcome the demerits above. In the ESEA, four evolutionary operators are designed to enhance the evolutionary structure. Besides, the ESEA employs four effective search strategies under the framework of the self-adaptive learning. Four groups of the experiments are done to find out the most suitable parameter values for the ESEA. In order to verify the performance of the proposed algorithm, 26 state-of-the-art test functions are solved by the ESEA and its competitors. The experimental results demonstrate that the universality and robustness of the ESEA out-perform its competitors. 展开更多
关键词 self-adaptive numerical optimization evolutionary al-gorithm stochastic search algorithm.
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Influences of Plant Growth Regulators, Basal Media and Carbohydrate Levels on Cell Suspension Culture of Panax ginseng 被引量:1
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作者 Tang Wei Wu Jiongyuan, Zhang Limei(Northeast Agricultural University, Harbin 150030, P R C) 《Journal of Northeast Agricultural University(English Edition)》 CAS 1995年第1期62-65,共4页
A cell suspension culture of Panax ginseng which may be continuously subcultured has been established. Embryogenic callus derived from clutured young leaves was used to initiate the culture.Plant growth regulators, ba... A cell suspension culture of Panax ginseng which may be continuously subcultured has been established. Embryogenic callus derived from clutured young leaves was used to initiate the culture.Plant growth regulators, basal medium formula and carbohydrate levels were examined to determine their various effects on suspension culture cell growth and development. The best selection of plant growth regulator, hasal medium and carbohydrate level is 2 mg / L 2,4-D: 0.5 mg / L KT,MS and 3% sucrose respectively. 展开更多
关键词 Panax ginseng cell suspension culture plant growth regulators
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Dynamic self-adaptive ANP algorithm and its application to electric field simulation of aluminum reduction cell 被引量:1
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作者 王雅琳 陈冬冬 +2 位作者 陈晓方 蔡国民 阳春华 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第12期4731-4739,共9页
Region partition(RP) is the key technique to the finite element parallel computing(FEPC),and its performance has a decisive influence on the entire process of analysis and computation.The performance evaluation index ... Region partition(RP) is the key technique to the finite element parallel computing(FEPC),and its performance has a decisive influence on the entire process of analysis and computation.The performance evaluation index of RP method for the three-dimensional finite element model(FEM) has been given.By taking the electric field of aluminum reduction cell(ARC) as the research object,the performance of two classical RP methods,which are Al-NASRA and NGUYEN partition(ANP) algorithm and the multi-level partition(MLP) method,has been analyzed and compared.The comparison results indicate a sound performance of ANP algorithm,but to large-scale models,the computing time of ANP algorithm increases notably.This is because the ANP algorithm determines only one node based on the minimum weight and just adds the elements connected to the node into the sub-region during each iteration.To obtain the satisfied speed and the precision,an improved dynamic self-adaptive ANP(DSA-ANP) algorithm has been proposed.With consideration of model scale,complexity and sub-RP stage,the improved algorithm adaptively determines the number of nodes and selects those nodes with small enough weight,and then dynamically adds these connected elements.The proposed algorithm has been applied to the finite element analysis(FEA) of the electric field simulation of ARC.Compared with the traditional ANP algorithm,the computational efficiency of the proposed algorithm has been shortened approximately from 260 s to 13 s.This proves the superiority of the improved algorithm on computing time performance. 展开更多
关键词 finite element parallel computing(FEPC) region partition(RP) dynamic self-adaptive ANP(DSA-ANP) algorithm electric field simulation aluminum reduction cell(ARC)
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Adjusting the Parameters of PI Regulator in All-electrical Tank Gun Control System by Computer Program
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作者 臧克茂 贺跃 +1 位作者 李匡成 李长兵 《Defence Technology(防务技术)》 SCIE EI CAS 2005年第2期140-145,共6页
Both the traverse subsystem and the elevation subsystem of the all-electrical tank gun control system are composed of electrical drive control system respectively. The parameters of PI regulator in these electrical dr... Both the traverse subsystem and the elevation subsystem of the all-electrical tank gun control system are composed of electrical drive control system respectively. The parameters of PI regulator in these electrical drive control systems affect the performance of the control system seriously. Up to now, there is not a simple and practical method for choosing regulator parameters, which are usually determined by repeated and continual readjustment. This method is low efficient, and the parameters got are not always optimal. A method for on-line adjusting the parameters of PI regulator in the electrical drive control system by computer program is introduced in this paper. The function of adjusting PI parameters of the electrical drive control system is realized by PC program written by VC++ and controlling program written by assemble language and by the communication between PC and DSP completed by the control MSCOMM in VC++6.0. The method as mentioned above which is applied for an all-electrical tank gun control system under development is proved very available, a better performance might be obtained for the all-electrical tank gun control system easily. 展开更多
关键词 PI regulator SERIAL communication all-electrical TANK GUN control system
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The Design of Digital Excitation Regulator
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作者 TIZong-li ZHAOYu-lin 《Journal of Northeast Agricultural University(English Edition)》 CAS 2001年第1期49-54,共6页
The digital excitation regulator is very popular in the small electric plant. This kind of regulator can im- prove the working condition of generator and its working efficiency. It is on the base of the 80C51 Micro-co... The digital excitation regulator is very popular in the small electric plant. This kind of regulator can im- prove the working condition of generator and its working efficiency. It is on the base of the 80C51 Micro-con- troller. The regulator can automatically finish some functions through the combination of software and hard- ware. Through the experiment we can know it is more intellectual than the traditional analog excitation regu- lator. 展开更多
关键词 Digital excitation regulator 80C51 Micro-controller ANALOG
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Regulatory puzzle of xyn1 gene (xylanase1) expression in Trichoderma reesei
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作者 Robert L Mach Elisabeth Würleitner +2 位作者 Astrid R Stricker Roman Rauscher Christian Wacenovsky 《浙江大学学报(农业与生命科学版)》 CAS CSCD 北大核心 2004年第4期431-431,共1页
Xylanase 1 (Xyn1) is one of the two major representatives of the xylanase system of T. reesei; the mechanisms governing its expression were analysed throughout this study. All factors and regulatory motifs responsible... Xylanase 1 (Xyn1) is one of the two major representatives of the xylanase system of T. reesei; the mechanisms governing its expression were analysed throughout this study. All factors and regulatory motifs responsible for transcriptional regulation and the model of their interplay in induction and repression will be presented. Using in vivo foot printing analysis of xylan-induced and glucose repressed mycelia, we detected three adjacent nucleotide sequences contacted by DNA-binding proteins. Protection within the inverted repeat of the Cre1 (SYGGRG) consensus sequence on the non coding strand under repressing conditions is in perfect agreement with the previously reported Cre1 dependent glucose repression of xyn1. Constitutive protein binding could be observed to a CCAAT-box and an inverted repeat of a 5′ GGCTAA 3′ sequence. EMSA with crude extracts from induced and repressed mycelia revealed that the latter motifs are sufficient for formation of the basal transcriptional complex under all conditions. The inverted repeat of GGCTAA closely resembles the consensus sequences of the cellulase and xylanase regulators Ace1, Ace2 and, Xyr1 (encoded by xyr1, cloned and characterised in this study) EMSA with heterologously expressed components of each factor and of the T. reesei Hap2/3/5 protein complex revealed that the basal transcriptional complex is formed by Xyr1 and the Hap2/3/5. Additionally to the Cre1 mediated carbon catabolite repression a yet unknown mechanism antagonizing induction of xyn1 expression could be elucidated. Latter occurs through competition of the repressor Ace1 and Xyr1 for the GGCTAA motif. In vivo proof for the relevance of identified motifs could be given through analysis of T. reesei transformants containing correspondingly mutated versions of the xyn1 promoter fused to the A. niger goxA gene. The results indicated that the basal as well as the induction level of xyn1 gene transcription is dependent on an interaction of Xyr1 with the GGCTAA motif while formation of the CCAAT-Hap2/3/5 complex slightly reduces induction. It can be concluded that mutations impairing protein binding in vitro lead to a loss of distinct regulatory functions in xyn1 gene expression in vivo. A respective model of gene regulation will be presented. 展开更多
关键词 TRICHODERMA gene regulation xylanase1 transcriptional factors
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Effects of anions on the structural regulation of Zn‑salen‑modified metal‑organic cage
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作者 GUO Qiaojia CAI Junkai DUAN Chunying 《无机化学学报》 SCIE CAS CSCD 北大核心 2024年第11期2203-2211,共9页
By virtue of a 3∶1 complementary coordination strategy,a chiral heteroleptic metal-organic cage that con-tains divergent functional units,Pd‑R(Zn),was precisely constructed via self-assembly of monodentate variationa... By virtue of a 3∶1 complementary coordination strategy,a chiral heteroleptic metal-organic cage that con-tains divergent functional units,Pd‑R(Zn),was precisely constructed via self-assembly of monodentate variational Zn-salen ligands RZn and NADH(reduced nicotinamide adenine dinucleotide)mimic modified tridentate ligands with square-planar Pd ions.UV-Vis and luminescence spectra experiments reveal that different anions could selec-tively interact with different sites of Zn-salen modified metal-organic cages to achieve the structural regulation of cage compound,by using the differentiated host-guest electrostatic interactions of counter ions with metal-organic hosts.Compared to other anions,the presence of chloride ions caused the most significant fluorescence emission enhancement of Pd‑R(Zn),meanwhile,the UV-Vis absorption band attributed to the salen aromatic backbone showed an absorption decrease,and the metal-to-ligand induced peak displayed a blue shift effect.Circular dichro-ism and ^(1)H NMR spectra further demonstrate that the introduction of chloride anions is beneficial to keeping a more rigid scaffold. 展开更多
关键词 metal-organic cage Zn-salen host-guest electrostatic interaction ANIONS structural regulation
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兰科植物花期调控技术及分子机理研究进展 被引量:2
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作者 陈露 李青女 +3 位作者 郑佳桐 王奕晴 翟俊文 吴沙沙 《植物遗传资源学报》 北大核心 2025年第1期1-13,共13页
兰科是被子植物中最大的科之一,物种繁多,分布广泛,因其奇特的花型、丰富的花色和持久的花期,具有极高的观赏价值。兰科植物也是国际上贸易最多的花卉之一,具有极高的经济价值。其开花时间和花朵品质是影响兰科植物观赏价值的重要因素,... 兰科是被子植物中最大的科之一,物种繁多,分布广泛,因其奇特的花型、丰富的花色和持久的花期,具有极高的观赏价值。兰科植物也是国际上贸易最多的花卉之一,具有极高的经济价值。其开花时间和花朵品质是影响兰科植物观赏价值的重要因素,但由于大部分兰科植物的自然花期与市场需求错位、开花整齐度低、开花品质不佳,极大地限制了兰花产业的发展。因此,如何调控兰花花期、提升兰花花朵品质对兰科植物的生产和应用具有重要意义。本文结合国内外研究对兰科植物的花芽分化进程、花期调控技术及开花相关的分子调控机理进行综述,总结出兰科植物花芽分化的特征、兰科植物花期调控相关基础研究与技术存在的问题、兰科植物相关的开花途径以及蝴蝶兰相关的开花机理与花期调控技术,提出兰科植物花期调控机理和花期调控技术具有潜在研究价值的方向,以期为兰科植物的花期调控研究、规模化生产和品质提升提供参考。 展开更多
关键词 兰科植物 花芽分化 花期调控 分子机理
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数据垄断何以规制? 被引量:4
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作者 曹阳 《东方法学》 北大核心 2025年第1期46-59,共14页
在数字经济引领下,数据为数字企业等经济活动相关各方带来了显著的竞争优势,但也容易异化为相应的反竞争壁垒。由此需要剖析数据引致垄断的缘由,在不同要素间加以权衡,并透视其危害,以揭示规制必要性。尤其不能忽视数据垄断规制现存的... 在数字经济引领下,数据为数字企业等经济活动相关各方带来了显著的竞争优势,但也容易异化为相应的反竞争壁垒。由此需要剖析数据引致垄断的缘由,在不同要素间加以权衡,并透视其危害,以揭示规制必要性。尤其不能忽视数据垄断规制现存的诸多问题,主要包括规制原则与目标,规制手段与分析范式等理念方面的问题,以及数据分布、权属与类型化,相关数字平台事前—事中或结构性规制,数据开放或共享,相关要件认定等制度方面的问题,须逐一展开探讨。进而需要引入动态系统论等新方法,循此进路,相应的理念转捩与制度革新势在必行,以寻觅到针对上述问题更有效的解决之道。 展开更多
关键词 数字经济 数据治理 数据垄断 数据垄断规制 结构性规制 反垄断
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行政相对人数字画像与差别化规制决策 被引量:1
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作者 王瑞雪 《政治与法律》 北大核心 2025年第4期161-176,共16页
在技术赋权的背景下,行政机关通过信息汇集大幅提升了对行政相对人异质性的掌握程度,逐渐形成了更具针对性的差别化规制决策方案。随着行政相对人数字画像的规制流程日渐兴起,它可大致被界分为“记录-刻画-应用”三个节点。记录行政相... 在技术赋权的背景下,行政机关通过信息汇集大幅提升了对行政相对人异质性的掌握程度,逐渐形成了更具针对性的差别化规制决策方案。随着行政相对人数字画像的规制流程日渐兴起,它可大致被界分为“记录-刻画-应用”三个节点。记录行政相对人的信息是信用监管等诸多制度的基础,无形之中强化了规制体系的威慑程度;行政机关应当审慎汇集行政记录,避免将本不相关的信息无差别地纳入个体档案。刻画行政相对人数字画像既有可能基于其丰富的差异性,也有可能在分级分类监管安排下回应某种共性,显著延伸了行政权力边界;行政机关应当对数字画像的真实性、准确性负责,正视过多干预对个体的侵扰。应用行政相对人数字画像,在一定程度上增加了执法的回应性,却可能面临形式平等与实质平等之间的紧张关系;行政机关既应尊重行政相对人的合理差别,又要避免将差别化的行政监管演变为系统性的算法歧视,还须警惕以合理差别为外衣的新型“一刀切”规制方案。政府的差别化规制决策方案应当精细设计、审慎考量,才能更为通顺地融入常态化统一监管过程。 展开更多
关键词 信用监管 平等原则 合理差别 回应性规制 风险规制
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加强人工智能监管与治理 被引量:2
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作者 郭朝先 《北京工业大学学报(社会科学版)》 北大核心 2025年第3期19-25,共7页
鉴于人工智能发展存在巨大的不确定性,如果不能适当监管和治理,人类社会很可能出现一个“反乌托邦未来”,良好监管和治理是人工智能健康发展的必要保障机制。当前,人类正进入一个巨大的不确定时代,人工智能发展已到了“奥本海默时刻”,... 鉴于人工智能发展存在巨大的不确定性,如果不能适当监管和治理,人类社会很可能出现一个“反乌托邦未来”,良好监管和治理是人工智能健康发展的必要保障机制。当前,人类正进入一个巨大的不确定时代,人工智能发展已到了“奥本海默时刻”,加强人工智能监管治理刻不容缓。人工智能监管治理目标是要实现发展与安全、监管治理与国际竞争的平衡,中国人工智能监管治理既要促进国内人工智能产业安全发展,还要有利于抢占全球人工智能监管治理规则制高点。为有效实现监管目标,中国人工智能监管应坚持“以人为本,智能向善”、推进包容审慎监管、加强监管治理国际合作等基本理念。加强人工智能监管治理需结合人工智能技术发展特点,及时更新监管制度,创新监管方式,主要措施有:推进基于风险的监管方式,实行敏捷监管,推进“软法”与“硬法”协同监管,采用“沙盒监管”,建立“吹哨人”制度。 展开更多
关键词 人工智能 奥本海默时刻 智能向善 敏捷监管 沙盒监管
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