Northwest Normal University

Health intertemporal decision-making is related to the health and well-being of individuals and the nation. However, its cognitive processing remains poorly understood. From a healthcare perspective, the current study adopts a dual-processing theory framework and employs the food time discount rate as a measurement paradigm to systematically examine the relationship between health behaviors and health intertemporal decision-making, as well as their underlying cognitive processing.

The current study consists of three interconnected sub-studies. Study 1 recruited 397 participants from northwestern and southwestern China, who were asked to rate 21 health behaviors across three dimensions: required effort, duration, and health impact. Cluster analysis was then used to test whether health behaviors could serve as proxy indicators of health intertemporal decision-making. Study 2 recruited 156 participants from northwestern China and explored whether health intertemporal decision-making simultaneously relies on heuristic and analytical processing by manipulating emotional tasks (heuristic processing) and working memory tasks (analytical processing). Study 3 recruited 30 participants from northwestern China and employed event-related potential (ERP) technology to compare intuitive preferences in health intertemporal decision-making under manipulations of time intervals.

The results of Study 1 indicate that, compared to short-term-effortless health behaviors, long-term-effortful health behaviors scored significantly higher on effort investment (t = 22.902∗∗∗) and duration (t = 16.607∗∗∗), but significantly lower on health impact (t = -18.779∗∗∗), suggesting that health behaviors can be categorized into two types: long-term-effortful health behaviors corresponding to delayed large benefits and short-term-effortless health behaviors corresponding to immediate small benefits. This provides a feasible method for indirectly measuring health intertemporal decision-making through health behaviors. The results of Study 2 showed a significant interaction between heuristic and analytical processing in health intertemporal decision-making (F(1, 147) = 4.934, p = 0.028, η_p² = 0.032). Moreover, individuals exhibited higher discount rates and a stronger preference for immediate gratification in unhealthy food contexts (F(1, 147) = 16.886, p < 0.001, η_p² = 0.103), suggesting that health intertemporal decision-making conforms to a dual-process model. The results of Study 3 showed that when presented with unhealthy foods, individuals exhibited a stronger preference for immediate rewards (F(1, 24) = 0.391, p = 0.538, η_p² = 0.016) and relied more on heuristic processing (N1: F(1, 24) = 1.258, p = 0.273, η_p² = 0.050; P2: F(1, 24) = 0.259, p = 0.615, η_p² = 0.011).

Current research indicates that healthy behaviors can serve as indirect measures of health intertemporal decision-making, which follows the dual-process theory, and that unhealthy foods are more susceptible to reliance on heuristic processing. This not only expands the applicability of dual-process theory in health intertemporal decision-making but also provides theoretical support for intervention strategies based on delayed gratification and inhibitory control, thereby offering new insights into promoting individual health outcomes.

The electrochemical detection of the purine bases including guanine (G) and adenine (A) is very important in the field of biological analysis for disease diagnosis and biomedical research. In this study, copper ion doped metal-organic framework (UiO-66) composite with MXene was synthesized to construct an electrochemical sensing platform towards guanine and adenine. UiO-66 exhibited high specific surface area and high porosity for analyte adsorption, copper ion doping enhanced electrochemical activity of the composite, and MXene ensured excellent electrical conductivity and hydrophilicity. The synergistic effect of these components greatly improved the sensing performance. The developed electrochemical sensor Cu@UiO-66-MXene/GCE realized the sensitive simultaneous detection of guanine and adenine with wide linear range (1.0-230 μM for G and A), low detection limits (LODs were 0.20 μM for G and 0.18 μM for A) and satisfactory repeatability and reproducibility. Especially, the sensor exhibited an outstanding stability with a signal retention rate of over 90 % even after one month. This sensor has been successfully applied in analysis of herring sperm DNA, which provided a simple and efficient strategy for the detection of purine bases in biological samples, and was expected to promote the development of related bioanalysis fields.

Water electrolysis is a promising route to sustainable hydrogen, but catalysts often corrode and operate slowly in high-salinity environments. We develop a dual-sided single-atom bridge (DS-SAB) electrocatalyst by isolating Fe single atoms on a Janus N-doped carbon matrix (DS-FeSACs-C@NC). The Fe-N_x/C side optimizes oxygen evolution reaction (OER) by modulating OH^- adsorption, while the FeC side accelerates hydrogen evolution reaction (HER) by facilitating H* intermediate desorption. The Janus interlayer with vertically aligned graphene edges and N groups act as an anion-repelling barrier without sacrificing ionic conductivity. As a result, DS-SAB delivers record-low overpotentials of 76 mV (HER) and 253 mV (OER) at 10 mA cm^-2 in 0.1 M H₂SO₄, and sustains 10 mA cm^-2 for over 200 h. These achievements are attributed to the bidirectional electron transfer between Fe-N_x/C and FeC sites, which tunes adsorption barriers, while an interfacial electric field accelerates electron flow, lowers impedance, and boosts catalytic kinetics. This work offers a paradigm for designing corrosion-resistant catalysts in complex electrolytes through atomic-scale interface control.