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Intercropping can improve light interception and crop yield on limited farmlands. The light interception rate in intercropping is determined by row configuration. Quantifying the spatio-temporal light interception of intercrops is very important for improving crop yields by optimizing the row configuration. A two-year field experiment was conducted at two sites to quantify the responses of the light interception rate of intercrops to five treatments: two rows of maize alternated with three rows of soybean (2M3S), two rows of maize alternated four rows of soybean (2M4S), two rows of maize alternated five rows of soybean (2M5S), sole soybean (SS), and sole maize (SM). We developed a multiple regression model based on the sine of the solar elevation angle (sin(h)) and crop leaf area density (LAD) to quantify the spatio-temporal light interception of intercrops. The predicted light interception rate was positively correlated with the measured values of photosynthetically active radiation (R2 > 0.814) and dry matter (R2 > 0.830). Increasing soybean rows led to an increase in light interception of both soybean and the lower layer of maize. However, this also resulted in a decrease in light interception in the upper layer of maize. At the two sites, compared to 2M3S, the annual average cumulative light interception of soybean in 2M5S increased by 44.73% and 47.18%, that of the lower layer of maize in 2M5S increased by 9.25% and 8.04%, and that of whole canopy of maize decreased by 13.77% and 17.74% respectively. The changes in dry matter and yield of intercrops were consistent with the change in light interception, which further verified the high accuracy of the light interception model. The annual average maize yield of 2M5S was 6.03% and 6.16% lower but the soybean yield was 23.69% and 28.52% higher than that of 2M3S. On the basis of system yield, the best performance was recorded in 2M4S at the two sites. In summary, the newly created light interception model performs well in the quantification of the temporal and spatial changes in crop light interception in strip intercropping and has potential applications in other configurations. Optimizing row configurations across climatic regions to enhance light interception and yield at the system level will become a future target. [ABSTRACT FROM AUTHOR]

BACKGROUND: Relay intercropping of maize and soybean can improve land productivity. However, the mechanism behind N2O emissions in this practice remains unclear. A two‐factor randomized block field trial was conducted to reveal the mechanism of N2O emissions in a full additive maize–soybean relay intercropping. Factor A was three cropping systems – that is, monoculture maize (Zea mays L.), monoculture soybean (Glycine max L. Merr.) and maize–soybean relay intercropping. Factor B was different N supply, containing no N, reduced N and conventional N. Differences in N2O emissions, soil properties, rhizosphere bacterial communities and yield advantage were evaluated. RESULTS: The land equivalent ratio was 1.55–2.44, and the cumulative N2O emission (CEN2O) was notably lower by 60.2% in intercropping than in monoculture, respectively. Reduced N declined CEN2O without penalty on the yield advantages. The relay intercropping shifted soil properties – for example, soil organic matter, total N, NH4+ and protease activity – and improved the soil microorganism community – for example, Proteobacteria and Acidobacteria. Intercropping reduced CEN2O by directly suppressing nirS‐ and amoA‐regulated N2O generation during soil N cycling, or nirS‐ and amoA‐mediated soil properties shifted to reduce CEN2O indirectly. Reduced N directly reduced CEN2O by decreasing soil N content and reducing soil microorganism activities to alleviate N2O produced in soil N cycling. CONCLUSION: Conducting a full additive maize–soybean relay intercropping with reduced nitrogen supply provides a way to alleviate N2O emissions without the penalty on the yield advantage by changing rhizosphere bacterial communities and soil N cycling. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

In the maize-soybean intercropping system, varying degrees of maize leaf shading are an important factor that reduces the uniformity of light penetration within the soybean canopy, altering the soybean canopy structure. Quantitative analysis of the relationship between the soybean canopy structure and canopy photosynthesis helps with breeding shade-tolerant soybean varieties for intercropping systems. This study examined the canopy structure and photosynthesis of intercropped soybeans during the shading stress period (28 days before the corn harvest), the high light adaptation period (15 days after the corn harvest), and the recovery period (35 and 55 days after the corn harvest), using a field high-throughput phenotyping platform and a plant gas exchange testing system (CAPTS). Additionally, indoor shading experiments were conducted for validation. The results indicate that shade-tolerant soybean varieties (STV varieties) have significantly higher yields than shade-sensitive soybean varieties (SSV varieties). This is attributable to the STV varieties having a larger top area, lateral width, and lateral external rectangular area. Compared to the SSV varieties, the four top areas of the STV varieties are, on average, 52.09%, 72.05%, and 61.37% higher during the shading stress, high light adaptation, and recovery periods, respectively. Furthermore, the average maximum growth rates (GRs) for the side mean width (SMW) and side rectangle area (SRA) of the STV varieties are 62.92% and 22.13% in the field, and 83.36% and 55.53% in the indoor environment, respectively. This results in a lower canopy overlap in STV varieties, leading to a more uniform light distribution within the canopy, which is reflected in higher photosynthetic rates (Pn), apparent quantum efficiency, and whole-leaf photosynthetic potential (WLPP) for the STV varieties, thereby enhancing their adaptability to shading stress. Above-ground dry matter accumulation was higher in STV varieties, with more assimilates stored in the source and sink, promoting assimilate accumulation in the grains. These results provide new insights into how the superior canopy structure and photosynthesis of shade-tolerant soybean varieties contribute to increased yield. [ABSTRACT FROM AUTHOR]

Stretchable organic photovoltaics (OPVs) are pivotal for advancing conformable electronics, yet achieving both efficient and intrinsically stretchable OPVs remains a significant challenge. The main issue is maintaining electronic and mechanical properties under deformation. Here, a ternary blend system, PTzBI‐oF:PYIT:EVA is presented, incorporating ethylene‐vinyl acetate (EVA) to establish a conjugated and elastomeric dual‐network morphology. The elastomer network dissipates applied stress, preserving the crystalline packing of the conjugated network and enabling improved mechanical stability of charge carrier generation and transport. Specifically, with 15% EVA content, the ternary blend achieved a power conversion efficiency (PCE) of 15.28% in rigid devices and exhibited a crack onset strain of 17.23%. Notably, the stretchable OPVs retained over 80% of their initial PCE under 30% strain. These findings underscore the potential of conjugated and elastomeric dual‐network morphology in developing high‐performance stretchable electronics for various applications. [ABSTRACT FROM AUTHOR]

Tunnel engineering is a complex and multidisciplinary field that requires the integration of geological expertise, advanced modeling techniques, and practical engineering solutions. The research compiled in the Special Issue "Tunnels and Tunneling" makes significant contributions to the field by addressing the diverse geological conditions and intricate challenges inherent in tunnel construction. These insights are crucial for enhancing the safety, efficiency, and sustainability of tunnel projects worldwide. The studies in this Special Issue provide a comprehensive understanding of the various challenges and innovative solutions in tunnel engineering. They offer valuable insights and practical guidelines for designing, constructing, and maintaining safe and stable tunnel structures across different geological settings. In addition, geological challenges in specific regions, such as the Three Gorges Reservoir area, the Hengduan Mountains, and the Tibetan Plateau, require tailored approaches. A key theme in many of the comparative studies is the importance of accurate risk assessment to ensure tunnel safety. In regions prone to geological hazards, landslide susceptibility mapping and risk assessment are critical. Innovative approaches, such as machine learning models, are highlighted for their potential to predict and manage landslide risks effectively. [ABSTRACT FROM AUTHOR]

Considering the rapid expansion of the economy and the increasing demand for infrastructure development, the scale of the tunnelling is expanding, and tunnel is inevitably excavated under unfavourable geological conditions. Consequently, this brings multitude of risks and challenges to tunnels and tunnelling. This paper summarizes the engineering issues associated with five unfavourable geological conditions: soft soil strata, soft and hard composite strata, spatially variable strata, karst strata and subsea conditions. Various analysis methods for deformation problem of tunnel and tunnelling under these unfavourable geological conditions are discussed. The mechanisms of the progressive failure of tunnel faces and collapses of caves in karst tunnels are also presented, as well as the risk assessments and prevention strategies for karst tunnel and water inrush occurrences of subsea tunnel. Furthermore, the analysis of the response of subsea tunnels to dynamic loads such as wave forces and earthquakes is summarized. Additionally, the analysis and prevention techniques for constructing subsea tunnels in fault zones are also considered. Finally, this paper offers a glimpse into potential research directions for future analysis relevant to the topic discussed, aiming to provide guidance for secure construction and maintenance tunnels under unfavourable geological conditions. [ABSTRACT FROM AUTHOR]

In order to study the long-term settlement and its variation law for shield tunnel under combined action of surface load, train load, and consolidation settlement of under-consolidated soft soil, a finite element model is established by PLAXIS to calculate the long-term settlement of shield tunnel under external action based on the Nansha-Zhuhai (Zhongshan) intercity line in Guangzhou. The effect of each influencing factor on long-term settlement is analyzed by single factor sensitivity analysis and nonlinear fitting method, and five key influencing factors are identified. The calculation method of long-term settlement and optimal tunnel depth is proposed. The results show that: (1) The overconsolidation ratio and tunnel depth have the greatest influence on long-term settlement, followed by the load magnitude, load width, and train load, while the effects of load distance, train speed, and permeability coefficient on long-term settlement can be neglected. (2) In order to solve the long-term settlement of shield tunnel, a calculation method is proposed for shield tunnel in under-consolidated soft soil under static and dynamic load, and the calculation result is in good agreement with the simulation result. (3) By taking the control value of 20 mm for shield tunnel deformation specified in the national standard as the tunnel settlement control value, and substituting it into the equation for longterm settlement, the equation for optimal tunnel depth is obtained. The under-consolidation characteristics of soft soil have the greatest influence on the optimal tunnel depth. In order to effectively control the long-term settlement, it is suggested that the entire tunnel should be constructed in soil with better quality. If a tunnel has to be constructed in mud and mucky soil strata, foundation treatment should be carried out, and drainage consolidation should be performed to improve the consolidation degree of soil. [ABSTRACT FROM AUTHOR]

In the advancement of organic photovoltaics (OPV) toward scale‐up production, how to mitigate the batch instability of electron‐donating polymers originated from varied molecular weights remains a great challenge. By taking into consideration the relationship between the molecular weight of electron‐donating polymers and the relevant critical concentration (c*) of the solution, herein it is demonstrated that the aggregation behavior of the electron‐donating polymers can be tailored through manipulating c* of the polymer solution. It is interesting to note that the excessive aggregation in low‐molecular‐weight fractions can be circumvented while the favorable mixing ratio can be identified. By preparing the binary bulk heterojunction film under c*‐defined conditions for mixed‐molecular‐weight polymers, a notable power conversion efficiency of 19.1% for binary devices is achieved. Of particular importance is that a linear interrelation can be established between the c* for the maximum PCE and c* for the low‐molecular‐weight fraction aggregation, validating those straightforward spectra measurements can accurately and rationally guide the molecular weight mixing of photovoltaic donor polymers, thereby fully harnessing the potent driving force and affinity inherent to the low‐molecular‐weight fractions. These findings offer a straightforward and logical framework for addressing batch variability in the large‐scale production of high‐performance OPV devices. [ABSTRACT FROM AUTHOR]

Artificial intelligence (AI) has the potential to revolutionize various domains by automating language-driven tasks. This study evaluates the effectiveness of an AI-assisted methodology, called the "POP Title AI Five-Step Optimization Method," in optimizing content titles on the RED social media platform. By leveraging advancements in natural language generation, this methodology aims to enhance the impact of titles by incorporating emotional sophistication and cultural proficiency, addressing existing gaps in AI capabilities. The methodology entails training generative models using human-authored examples that align with the aspirations of the target audience. By incorporating popular keywords derived from user searches, the relevance and discoverability of titles are enhanced. Audience-centric filtering is subsequently employed to further refine the generated outputs. Furthermore, human oversight is introduced to provide essential intuition that AI systems alone may lack. A total of one thousand titles, generated by AI, underwent linguistic and engagement analyses. Qualitatively, 65% of the titles exhibited intrigue and conveyed meaning comparable to those generated by humans. However, attaining full emotional sophistication remained a challenge. Quantitatively, titles emphasizing curiosity and contrast demonstrated positive correlations with user interactions, thus validating the efficacy of these techniques. Consequently, the machine-generated titles achieved coherence on par with 65% of human-generated titles, signifying significant progress and potential for further refinement. Nevertheless, achieving socio-cultural awareness is vital to match human understanding across diverse contexts, thus presenting a critical avenue for future improvement in the methodology. Continuous advancements in AI can enhance adaptability and reduce subjectivity by promoting flexibility instead of relying solely on manual reviews. As AI gains a deeper understanding of humanity, opportunities for its application across various industries through experiential reasoning abilities emerge. This case study exemplifies the nurturing of AI's potential by refining its skills through an evolutionary process. [ABSTRACT FROM AUTHOR]

Although travelers are frequently accompanied by abdominal discomfort and even diarrhea, not every trip can cause this issue. Many studies have reported that intestinal microbes play an important role in it. However, little is known about the reason for the dynamics of these intestinal microbes. Here, we delved into the effects of short-term travel on the gut microbiota of 12 healthy individuals. A total of 72 fecal samples collected before and after one-week travel, alongside non-traveling controls, underwent amplicon sequencing and a series of bioinformatic analyses. We found that travel significantly increased intra-individual gut microbiota fluctuations without diarrhea symptoms. In addition, the initial composition of the gut microbiota before travel emerged as a crucial factor in understanding these fluctuations. Travelers with stable microbiota exhibited an enrichment of specific probiotic bacteria (Agathobaculum, Faecalibacterium, Bifidobacterium, Roseburia, Lactobacillus) before travel. Another batch of data validated their predictive role in distinguishing travelers with and without the gut microbial disorder. This work provided valuable insights into understanding the relationship between gut microbiota and travel. It offered a microbiota-centric perspective and a potential avenue for interventions to preserve gut health during travel. [ABSTRACT FROM AUTHOR]

Crops often face light intensity fluctuations in natural settings. Intercropping is widely used to improve crop yield and resource utilization worldwide, but crops suffer from high-frequency and high-intensity light fluctuations due to mutual crop influence. Soybean is an important legume crop and is often intercropped with other crops, but little is known about soybean's response to light fluctuation environments. Herein, three fluctuation frequencies (1, 10, and 20 min/cycle) were used to analyze soybean photosynthesis responses by measuring leaf growth, chlorophyll content, gas exchange, and electron transfer. Our data revealed that faster fluctuation frequencies led to the stronger suppression of soybean morphology and photosynthesis, with significant reductions of 31.31% and 21.58%, respectively. Damage to photosystems II (PSII) and I (PSI) also intensified, with significant decreases of 18.52% and 18.38% in their effective quantum yields Y(II) and Y(I). Additionally, increased fluctuation frequency exacerbated the consumption of the plastoquinone pool and linear electron flow but enhanced the cyclic electron flow across the thylakoid membrane and, thus, increased heat dissipation in PSII. Our findings indicate that an increased fluctuation frequency inflicted more severe damage on the soybean photosynthesis system. However, PSI-enhanced CEF improved NPQ and coordinated photoprotection to some extent. [ABSTRACT FROM AUTHOR]