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Dynamical Effects of the Load on Self-sustained Oscillators
JU Xiaolin, WANG Hongli
Acta Scientiarum Naturalium Universitatis Pekinensis    2023, 59 (4): 539-546.   DOI: 10.13209/j.0479-8023.2023.029
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The effect of loads on self-sustained oscillators was studied by using numerical simulations and theoretical analysis with simple biological and chemical oscillators. Analyses of dynamical properties of the oscillators revealed that, the scheme in which the oscillators driving the load through indirect coupling via an insulator helped keeping the robustness of dynamical properties of the oscillators. The binding affinity between the load and its upstream module and the total amount of functional insulator were two key parameters that affected the relative amplitude of the load. The introduction of insulator module to the system can break the trade-off between the oscillations of the load and the retroactivity in the direct coupling scheme. Calculations of the free energy dissipation suggested that an increase in the free energy dissipation did not necessarily mean a decrease in the retroactivity or enhanced oscillations in the load.
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Review of Observational Studies on Ambient Atmospheric Formaldehyde in China
LIU Yuehui, WANG Hongli, LU Keding
Acta Scientiarum Naturalium Universitatis Pekinensis    2023, 59 (2): 331-343.   DOI: 10.13209/j.0479-8023.2023.007
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This paper reviews the current status of observational studies on atmospheric formaldehyde in China, and discusses the atmospheric formaldehyde concentration levels, the relative contributions of primary and secondary sources, and the inventory of formaldehyde emissions from anthropogenic sources. On this basis, the authors point out some limitations of the existing studies and make targeted suggestions for future observational studies on formaldehyde.
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Evaluation and Impact Factors of Spatial Supply and Demand of Public Sports Facilities in Shenzhen
WU Jiansheng, QIAN Yun, WANG Hongliang, ZHU Huizhen, WANG Han
Acta Scientiarum Naturalium Universitatis Pekinensis    2022, 58 (6): 1101-1110.   DOI: 10.13209/j.0479-8023.2022.088
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From the perspective of 10-minute fitness circle, points of interest (POI), mobile signal data and other data were employed in this research. The accessibility of public sports facilities was measured with network analysis in GIS and Gini coefficient was used to analyze the equity of the supply and demand matching degree of public sports facilities in Shenzhen. The influencing factors of spatial supply and demand of public sports facilities were explored by geographical detectors. The results showed that, first, the overall accessibility of public sports facilities in Shenzhen was relatively high, which basically met the requirements of 10-minute fitness circle. Second, the distribution of public sports facilities was relatively fair. The distribution of facilities in different streets of the same municipal district was highly fair while the equity between municipal districts could be further improved. Third, the relationship between supply and demand in Yantian, Pingshan, Dapeng District was well-matched while sports facilities in the subdistrict at the junction of Futian District and Luohu District were centralized distributed, which set a limitation to the ability of service. Finally, land price was the most important factor affecting the spatial supply-demand relationship of public sports facilities in Shenzhen, followed by the density of road network and the number of bus stops. The total population and the proportion of man-made surface also had a certain impact on the supply and demand relationship.
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Spatial Fitness of Urban Public Resources and Population Distribution: Taking Shenzhen as an Example
WANG Hongliang, WU Jiansheng, GAO Yining, LIU Lu, YANG Weishi, PENG Zifeng, GUAN Qingchun
Acta Scientiarum Naturalium Universitatis Pekinensis    2021, 57 (6): 1143-1152.   DOI: 10.13209/j.0479-8023.2021.088
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Based on the support of the new data environment, the spatial adaptability of urban public resources and population distribution in Shenzhen is analyzed from two aspects of adaptability and matching relationship by using various spatial quantization methods, such as kernel density estimation, nearest neighbor analysis, multidistance spatial clustering, cooperative location quotient and two-step mobile search. The results show that the spatial adaptability of public resources and population distribution in different cities has obvious similarity, which is similar in spatial morphology, distribution pattern and proximity effect. Spatial matching relationship between urban public resources and population distribution is different. The non-matching characteristics of urban public resources and population density indicate the “mismatch” and “dislocation” relationship between supply and demand of urban public resources. Aiming at the spatial adaptability of resource elements, the optimization suggestions for three kinds of public resources, such as park green space, school education and health care, are put forward from two scales of city and community.
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Construction Land Expansion and Its Driving Force in Highly Urbanization Areas: A Case Study of Shenzhen City
WANG Hongliang, GAO Yining, WU Jiansheng, WANG Na, ZHAO Yuhao, PENG Zifeng, WANG Yanglin
Acta Scientiarum Naturalium Universitatis Pekinensis    2021, 57 (4): 707-715.   DOI: 10.13209/j.0479-8023.2021.045
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Based on the survey data of land use change, this paper studies the process and characteristics of urban construction land expansion in Shenzhen from 1996 to 2016 by analyzing the spatial and temporal changes, expansion intensity and landscape pattern of urban construction land, and reveals the spatial differentiation of urban construction land expansion in highly urbanized areas. Regression analysis model is used to explore the driving mechanism of social and economic factors on the expansion of construction land. The results show that the expansion of construction land in Shenzhen presents a continuous growth trend, and the expansion mode of new construction land is significantly different. Futian District and Luohu District are mainly expanded by interior filling, while Nanshan District and Baoan District are mainly expanded by external expansion. The difference between construction land extension intensity in different regions and the index of landscape pattern indicates that the spatial expansion of construction land is gradually changing from disorder, homogeneity, inefficient spread to orderly, heterogeneous and efficient utilization. Social and economic factors have a significant positive correlation with construction land expansion. The regression coefficient of resident population is the largest (0.578), and that of fixed assets investment is the smallest (0.000). Pearson correlation ranking is Resident population > Industrial structure >GDP> Fixed asset investment, indicating that population plays a decisive role in the expansion of construction land, and fixed asset investment is embodied in the function of connection. 
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Adaptive Functional Network with Thermal Robustness
LIU Ming, WANG Hongli
Acta Scientiarum Naturalium Universitatis Pekinensis    2019, 55 (4): 603-608.   DOI: 10.13209/j.0479-8023.2019.038
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Through the enumeration of the three-node gene regulatory network, the random sampling of the parameter space and the dynamics simulation, the adaptive gene transcriptional regulation networks with thermal robustness (namely temperature compensation) are found. The structural analysis of the thermally robust adaptive networks shows that there are three basic structures that can achieve adaptive dynamics with thermal robustness, and the complex adaptive networks with thermal robustness uses these three networks as the core skeletons. In order to investigate the sensitivity of the adaptability of the three-node adaptive network to the changes of various parameters in the network dynamics, the authors calculate the corresponding control coefficients of each parameter. The clustering analysis of the control coefficients shows that the mechanism of the three-node functional network to achieve thermal robustness is temperature isolation, that is, although all rate parameters in the network are temperature dependent, only the generation and degradation rates of the output nodes deviate significantly from zero and have opposite signs. Most thermal robustness is achieved by the antagonistic balance adjustment of the output nodes. 
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Intrinsic Noise in Biological Kinetic Proofreading Processes
WANG Chao, WANG Hongli
Acta Scientiarum Naturalium Universitatis Pekinensis    2015, 51 (6): 983-988.   DOI: 10.13209/j.0479-8023.2015.085
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By virtue of kinetic proofreading theory, the puzzles of selectivity and specificity common in cellar activities are successfully explained. The chemical master equation is adopted to describe stochastic processes of kinetic proofreading models with two and three middle steps. Stochastic properties around the steady state are analyzed with the linear noise approximation under various parameters. Relations between noise density and parameters are revealed with numerical simulation. The result suggest that noises propagate and escalate as reactions proceed, furthermore multiple reaction rates determine noise intensity.

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