Research on carbon emission quota allocation scheme under "Double Carbon" target: a case study of industrial sector in Henan Province.

To achieve China's "Double Carbon" target, overall carbon emissions should be effectively controlled, and carbon emission quota (CEQ) allocation is an important tool. This study develops carbon emission prediction, CEQ allocation, and scheme feasibility evaluation models based on the principles of fairness, efficiency, and economy. The purpose is to propose a suitable CEQ allocation scheme for the Industrial Sector in Henan Province (ISHP). The results show that (1) the allocation model combining the technique for order preference by similarity to ideal solution (TOPSIS) and the zero-sum gains DEA (ZSG-DEA) can trade off the fairness and efficiency principles. (2) The reallocation scheme has an environmental Gini coefficient of 0.393 (< 0.4), which maximizes efficiency while lowering the abatement costs by 126.268 billion yuan, making it an ideal scheme that considers multiple principles. (3) CEQ should be reduced in 7 subsectors of ISHP while increasing in 33 others. Carbon emissions from these 7 subsectors are high, and CEQ should be reduced in accordance with the fairness principle. Even if their abatement costs are high and CEQ rises according to the efficiency principle, the increase is much smaller than the decrease. The findings are useful for optimizing the CEQ allocation under the "Double Carbon" target.

Niche Suitability Evaluation and Path Selection for the High-Quality Development of Cities in the Yellow River Basin.

The urban development in the Yellow River basin (YRB) varies widely. Therefore, it is necessary to choose a development path that fits the characteristics of each city to achieve high-quality development. The purpose of this paper is to address the problem of how to choose a characteristic path for high-quality development and clarify its suitability for YRB cities. Firstly, based on data from 50 YRB cities from 2011 to 2020, the suitability evaluation was carried out from the perspective of an ecological niche, followed by the measurement of sub-dimensional niche breadth and overlap. The results confirmed the great diversity of development between cities and the intense competition for resources. Then, based on the classification approach using the k-means method, this study proposes a method for selecting a suitable path for high-quality development. It classifies the suitable paths into 3 major types with 7 minor types and recommends policies for the suitable paths for YRB cities. The systematic thinking and specific path selection method for the high-quality development of YRB cities is not only of practical significance for implementing city classification strategies but also provides a reference for the sustainable development of basin cities in other countries.

A perturbation analysis of rate theory of self-regulating genes and signaling networks.

A thorough kinetic analysis of the rate theory for stochastic self-regulating gene networks is presented. The chemical master equation kinetic model in terms of a coupled birth-death process is deconstructed into several simpler kinetic modules. We formulate and improve upon the rate theory of self-regulating genes in terms of perturbation theory. We propose a simple five-state scheme as a faithful caricature that elucidates the full kinetics including the "resonance phenomenon" discovered by Walczak et al. [Proc. Natl. Acad. Sci. U.S.A. 102, 18926 (2005)]. The same analysis can be readily applied to other biochemical networks such as phosphorylation signaling with fluctuating kinase activity. Generalization of the present approach can be included in multiple time-scale numerical computations for large biochemical networks.

Stochastic bifurcation, slow fluctuations, and bistability as an origin of biochemical complexity.

We present a simple, unifying theory for stochastic biochemical systems with multiple time-scale dynamics that exhibit noise-induced bistability in an open-chemical environment, while the corresponding macroscopic reaction is unistable. Nonlinear stochastic biochemical systems like these are fundamentally different from classical systems in equilibrium or near-equilibrium steady state whose fluctuations are unimodal following Einstein-Onsager-Lax-Keizer theory. We show that noise-induced bistability in general arises from slow fluctuations, and a pitchfork bifurcation occurs as the rate of fluctuations decreases. Since an equilibrium distribution, due to detailed balance, has to be independent of changes in time-scale, the bifurcation is necessarily a driven phenomenon. As examples, we analyze three biochemical networks of currently interest: self-regulating gene, stochastic binary decision, and phosphorylation-dephosphorylation cycle with fluctuating kinase. The implications of bistability to biochemical complexity are discussed.

Fluctuating enzyme and its biological functions: positive cooperativity without multiple states.

Positive, sigmoidal cooperativity is known to occur to a monomeric single-site enzyme with slow conformational fluctuations in its unbound (E) states when the enzyme undergoes steady-state catalytic turnover (mnemonic enzymes, hysteretic enzyme). We show that positive cooperativity occurs even when the E state is a single thermodynamic state, provided that the fluctuation amplitude of the state is sufficiently greater than that of the enzyme-substrate complex ES and the fluctuation times being comparable. This can occur even without mean structural change between E and ES. Slow conformational fluctuations are widely observed in enzymes. Our result suggests that enzymes with substrate association that reduces conformational fluctuations while maintaining fluctuation temporality can exhibit sigmoidal binding inside of living cells. Implications of this result on drug-target interactions are discussed.