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The valorization of lignocellulose has received increasing attention due to the diminishing of conventional fossil energy (coal, petroleum, and natural gas). Lignocellulosic biomass is the most important form of biomass, which is naturally abundant, widely distributed, easily accessible, and renewable in earth. Upgrading the nonedible lignocellulosic biomass into various fine-chemicals and liquid fuels is of great importance to the sustainable development of mankind and society. Heterogeneous catalysts have played a significant role in the transformation of lignocellulose, owing to their easy recovery, environmentally friendly, and stability feature. This review focuses on the conversion of lignocellulosic biomass into alcohols, acids, furan derivatives, ethylene glycol, and liquid hydrocarbon fuels using heterogeneous catalysts. A brief outlook is supplied at the end of this review to emphasize the challenges and prospective with respective to this interesting and important field. [Display omitted] • We focus on the production of sorbitol, EG, HMF, LA, hydrocarbons, and EtOH from cellulose over solid catalyst. • Challenges of using raw biomass were highlighted. • The balance of metal-acid in catalyst played an important role in the products distribution. • Developing heterogeneous catalysts with high efficiency and high stability was encouraged. [ABSTRACT FROM AUTHOR]

The mechanical properties of composites are closely related to the interfacial behavior, especially under the hygrothermal circumstance. A catalytic sizing agent of titanium epoxy is designed to enhance interfacial, mechanical, and anti-hygrothermal properties of high modulus carbon fiber (HMCF)/cyanate ester composites simultaneously. The mechanisms of interface enhancement and low hygroscopicity of composites are investigated. The titanium epoxy is synthesized and its catalytic effect on the curing of cyanate ester is proved. The interfacial properties of HMCF composites with catalytic sizing agents are improved to 95.5 MPa, which is attributed to the interphase with high crosslinking density and sufficient triazine rings and oxazolidinone structure due to preferential curing induced by interfacial catalysis, stimulating the smooth transition of interphase modulus. Further, the formed interphase exhibits few interface defects and low content of hydroxyl groups, which changes the moisture diffusion path and reduces saturated water absorption of composites to only 0.36 %, resulting in the release of interfacial wet stress concentration and high retention of mechanical properties in hygrothermal environment. The resultant composites with high stiffness, excellent temperature resistance, superior dimensional stability and low moisture absorption are expected to be applied to high-orbit space, aerospace, precision instruments. [Display omitted] • The interfacial, mechanical, and anti-hygrothermal properties of composites are improved via catalytic sizing agents. • Catalytic sizing agents induce preferential curing of resin at the interface. • Catalytic sizing agents stimulate the smooth transition of modulus and increase IFSS. • The interphase with high interfacial adhesion and low hygroscopicity changes the moisture absorption path in composites. [ABSTRACT FROM AUTHOR]

• The water extract of YZR improved OAB in SHR rats. • ECM-receptor interaction and calcium signaling pathways were enriched in multi-omics. • YZR reduced OAB symptoms by regulating TGFβ1-SMAD3 and Gq-PLCβ1 signaling pathways. Alpinia oxyphylla fructus without impurities and shells is called "Yi-Zhi-Ren" (YZR) in Chinese, and traditionally used to alleviate enuresis. The aim of this study was to investigate the effects and underlying mechanisms of YZR in the treatment of overactive bladder (OAB) in spontaneously hypertensive rats (SHR), a vascular disorder-related OAB model. A 3-week administration of YZR water extract (p.o.) was done, followed by urodynamics to measure bladder parameters. Changes in bladder structure were observed through H&E staining and Masson's staining. An integrated approach involving network pharmacology, transcriptomics and metabolomics was employed to elucidate the potential mechanisms of YZR, and the key proteins involved in the mechanisms were validated by Western blotting. Additionally, network pharmacology was used to predict the relationship between YZR's active components and validated proteins. YZR treatment significantly improved the bladder storage parameters, tightened the detrusor layer, reduced inflammatory infiltration, and decreased collagen proportion in the SHR bladder. These results indicated that YZR water extract can alleviate OAB symptoms and improve bladder structure. Integrated analysis suggested that YZR may affect extracellular matrix-receptor interaction and calcium signaling pathway. Western blotting results further confirmed that the reduction in key proteins, such as TGFβ1, p-SMAD3, collagen III, Gq and PLCβ1, involved in collagen synthesis and calcium signaling pathways after YZR treatment. Network pharmacology predicted that sitosterol, chrysin, and nootkatone were potential components responsible for YZR's therapeutic effect on OAB. YZR's mechanisms of action in treating OAB involved the TGFβ1-SMAD3 signaling pathway-related collagen synthesis and Gq-PLCβ1 calcium signaling pathway, which are associated with detrusor contraction frequency and strength, respectively. [Display omitted] [ABSTRACT FROM AUTHOR]

China purchases around 62% of the soybean that is traded internationally and is currently only 14.3% self-sufficient, which strains the global food supply. A key question is to what extent China can produce soybeans to meet its demand. Here we used 3 years of data for 26 soybean cultivars across 146 locations in China, combined with APSIM modeling, to quantify soybean yield spatial variations and the impact of varietal and climate changes on soybean yield potential. We further analyzed the key drivers of national soybean production and explored a potential solution to increase national soybean production with maize-soybean strip intercropping system based on data from 32 locations in the past 10 years. The results showed that the contrasting climate conditions across regions in China resulted in diverse maturity types of soybean cultivars, ranging from MG000 to MGⅧ, with grain yield ranging from 1.4 t ha−1 to 4.5 t ha−1. The key climate drivers are temperature at high latitude cool regions and radiation at low latitude hot and humid regions. The key physiological trait for increasing yield is grain number that is closely related to post-anthesis growth. There exists an obvious yield gap between potential yield and actual yield. At national level, total soybean productivity was limited by planting area due to competing maize crop. It remains difficult for soybean to replace maize due to economic competitiveness. However, maize-soybean strip intercropping offers a sustainable solution to produce an additional soybean crop with around half of the yield of a sole soybean while maintaining the current maize yield. This would enable to potentially produce additional 67.4 million tons of soybean yield each year, with minimum reduction of maize yield (land equivalent ratio of maize =0.96). Fully closing the gap between actual unit yield and potential yield level would only increase national soybean production by 8 million tons. Further increase in production rely on increasing soybean planting area is unrealistic due to the more profitable maize crop. Maize-soybean strip intercropping offers a sustainable solution to potentially produce additional 67.4 million tons of soybean yield while maintaining the current maize yield. • We used APSIM NG model to quantify the impact of varietal and climate changes on soybean yield potential. • Grain yield of soybean ranging from 1.4 t ha-1–4.5 t ha-1 across regions in China. • The key climate drivers and physiological trait for increasing soybean yield have been identified. • Maize-soybean strip intercropping would enable to potentially produce additional 67.4 million tons of soybean yield. [ABSTRACT FROM AUTHOR]

ZnO is a promising candidate for photocatalysts, whereas suffered from low activity due to the insufficient visible-light absorption and rapid recombination of photogenerated charges. In order to improve the visible-light catalytic activity of unmodified ZnO, a ZnO/Cu 2 O/CuO (ZCC) heterostructure photocatalyst constructed from in-situ growth of Cu-based MOF (HKUST-1) on ZnO nanosheets by in-situ growth was designed for photocatalytic H 2 evolution, which exhibited excellent visible-light H 2 production rate of 467.1 μmol h−1 g−1. It was confirmed that the enhanced photoactivity was mainly attributed to the wide visible-light absorption range and improvement of active sites. The construction of heterostructure promoted the migration and separation of photogenerated charges and enhanced the synergistic effect between the multicomponent hybrid semiconductor materials. This work highlights the design of using MOFs as precursor to construct metal oxide heterostructures with ZnO nanosheets for visible-light photocatalytic H 2 production. [Display omitted] • Construction of ZCC heterostructure from MOFs. • ZCC extends the light absorption range and increases the active site. • The activity of heterostructures was adjusted by varying the content of MOFs. • ZCC exhibited an improved H 2 production rate under visible light. [ABSTRACT FROM AUTHOR]

• We implemented the light interception model for strip intercropping into APSIM-Classic. • A quasi-Bayesian optimisation approach was used to derive parameter by constraining the model to LAI, biomass and yield. • Key model parameters were changed with row configuration, indicating a need to improve modelling physiology of intercrops. • A potential application is to optimize row configurations in strip intercropping across climates. Intercropping of two or more crop species increases the efficiency of resource use and often produces a greater yield per unit land area. The relative efficiency of intercropping depends on row configuration, but there is a shortage of modelling-based evaluation of alternative intercropping options due to the inadequacy of standard process-based crop models to simulate resource capture, growth and yield formation when the canopy is spatially structured in strips. We implemented a light interception model for strip crops into the APSIM Classic model and combined it with a quasi-Bayesian approach to derive the model parameters to simulate crop growth and grain yield in maize-soybean strip intercropping. We used 4 years of field data for 5 different row configurations to derive key model parameters for simulation of light interception, LAI dynamics, biomass growth and grain yield of maize and soybean intercrops. Key model parameters (e.g. RUE, k etc.) were found to change with row-spacing and configuration, posing challenges to simulate different configurations with a single parameter set. The potential ranges of these key parameters were derived by constraining the model to observed data. The model can be potentially used to evaluate impact of planting configurations on productivity of strip intercropping systems, but the variability of key model parameters among configuration treatments calls for further in-depth research to improve modelling physiology of strip intercrops. [ABSTRACT FROM AUTHOR]

3D assembled MOF-GH composite with high amphiphilic properties. • 3D porous hierarchical MOF-GH architectures were successfully synthesized. • The MIL-101-GH hybrid showed high affinity to both water and oils. • MIL-101-GH-TS-1 exhibited good heterogeneous catalytic performance toward 1-octene epoxidation.. Micro-nano surface with high-amphiphilic structures possesses fascinating physical properties and promising applications in many areas. Herein, we reported a three dimensional (3D) porous hierarchical architecture with internal crosslinked network structures constructed from metal-organic frameworks (MOFs) and graphene oxide (GO) through a facile self-assembly hydrothermal method. In contrast to conventional 3D graphene hydrogel with strongly hydrophobic structures, the resulting composite exhibited high-amphiphilic features with both highly hydrophilic and oleophilic ability, which could absorb water and oils simultaneously, owing to the synergistic effect between MOFs and reduced graphene oxide. MOFs acted as a dopant and intercalated between reduced graphene oxide layers, which could largely increase the specific surface areas of graphene hydrogels (GH) and artistically adjust the surface structures of pristine GH as well. Accordingly, the 3D porous hierarchical MIL-101-GH materials showed great absorption capacity for oil and water. The advantages of this high amphiphilic properties were proved by constructing a biphasic catalytic system with the introduction of molecular sieve into the 3D MIL-101-GH hybrid. As a result, the designing functionalized foam exhibited good catalytic performance in heterogeneous catalysis for epoxidation of olefins without addition of co-solvents. [ABSTRACT FROM AUTHOR]

[Display omitted] • Oriented transformation of GVL into gasoline fuels was achieved. • Nano-HZSM-5 with adjusting acidity and pore structure was designed. • Small particle sizes facilitated fast diffusion of reactants and products in the pore channels. • Reducing acid sites on external surface promoted the formation of C5+ hydrocarbons. γ-Valerolactone (GVL) is one of a promising and versatile platform compounds, derived from renewable biomass, that could be widely used as key raw materials for the production of high value-added chemicals and energy fuels. Here, we report the oriented transformation of GVL into gasoline range hydrocarbons through an integrated two-stage fixed-bed catalytic system. The catalytic upgrading strategy involved the GVL feeds converting to butene isomers mixture and CO 2 by ring-opening and decarboxylation without use of external H 2 over SiO 2 -Al 2 O 3 catalyst, coupled with the oligomerization of butene isomers intermediates to gasoline fuels over the nano-HZSM-5 catalyst. This integrated two-stage processes could greatly simplify the products separation, avoid the incompatibility of their reaction conditions, and effectively improve the catalytic stability. The selectivity and yield for target C 5−12 gasoline range fuels was high as 82.2 % and 58.7 %, respectively, and no obvious deactivation was observed with time on stream of 50 h. [ABSTRACT FROM AUTHOR]

[Display omitted] • γ-Valerolactone converting to butene was achieved. • Amorphous SiO 2 -Al 2 O 3 catalyst with adjustable acidity was prepared. • Lower acid sites facilitated the decarboxylation of pentenoic acid. • A two-stage integration system was developed for converting GVL to gasoline. γ-Valerolactone (GVL) as a sustainable platform compound could be converted to renewable fuels and chemicals, whereas directly converting GVL to target products remains still the challenge. In this work, we report an amorphous SiO 2 -Al 2 O 3 catalyst with adjustable acidity, which presented an excellent selectivity of 97.5 % butene at GVL conversion of 99.5 %, and remained an outstanding stability for 50 h. Appropriate weak and strong acid sites were the key for the ring-opening of GVL. Lower acid sites facilitated the decarboxylation of pentenoic acid (PEA), while higher acid sites promoted the cracking of PEA. Besides, a two-stage integration system was developed for converting GVL to C 5 + hydrocarbons via butene intermediate, giving a good yield of 57.6 % C 5 + hydrocarbons via combining the SiO 2 -Al 2 O 3 catalyst with nano-HZSM-5 together. [ABSTRACT FROM AUTHOR]

Early diagnosis is important to control COVID-19 outbreaks. This study aimed to assess how individual and area socioeconomic position and geographical accessibility to healthcare services were associated with the time to diagnosis among symptomatic COVID-19 patients in Hong Kong. Multivariable generalized linear regression was used to estimate the associations while adjusting for sociodemographic characteristics and case classification. This study found living in public rental housing and living in an area with low education were associated with longer time to diagnosis in the first wave of infections. Specifically, the risk of delayed diagnosis for public rental housing residents was mitigated by the higher density of public clinics/hospitals but was slightly increased by the higher density of private medical practitioners nearby. No such relations were found in the second wave of infections when the surveillance measures were enhanced. Given the grave impact of pandemics around the world, our findings call on taking inequalities into account when public health policies are being devised. [ABSTRACT FROM AUTHOR]

• The aromatic hydrocarbon components in jet fuel are synthesized in the gas phase. • Nano scale ZSM-5 was synthesized by only template of Tetrapropylammonium hydroxide. • The differences in the results of the alkylation reactions are demonstrated on different sized HZSM-5. • The effect of reaction conditions on the aromatic hydrocarbon components in jet fuel was demonstrated. C 8 -C 15 aromatics are used widely as key components of jet fuel, whereas effectively producing these aromatic components remains a big challenge. We reported the oriented synthesis of C 8 -C 15 aromatic components in jet fuel by alkylation of benzene with mixed ethylene and propylene in vapor-phase over nanosize ZSM-5 (N-ZSM-5) catalyst. The selectivity and yield of aromatics, mainly of carbon number ranging from 8 to 15, could be enhanced by decreasing the particle size of ZSM-5, owing to the faster mass transfer and shorter intraparticle diffusion route for reactants and target products during the reaction process, as well as by increasing the acid strength via decreasing the Si/Al molar ratio, thus improving the alkylation performance conspicuously. In addition, mesopore volume of N-ZSM-5 zeolite showed an increase tendency with decreased particle size, contributing to the carbon chain growth and diffusion of target products. The resultant N-ZSM-5 catalyst showed superior benzene conversion of 40.3%, ethylene and propylene conversion of 99.5% and 99.2%, with aromatic C 8 -C 15 selectivity and yield of 94.8% and 54.9%, respectively, under the optimized reaction conditions. [ABSTRACT FROM AUTHOR]

• Observed phenology, LAI, biomass & yield of 72 soybean cultivars are presented. • APSIM captured LAI & biomass dynamics of multiple cultivars across different years. • APSIM improvement need to include simulation of grain setting & its impact on yield. • We provided the first data set in APSIM for modelling soybean genotypes in China. This paper combines the analysis of soybean growth data with modelling to quantify cultivar differences and to evaluate the ability of the APSIM-Soybean model for simulation of soybean biomass and grain yield. Crop data include main developmental stages, leaf area index (LAI), above ground biomass, grain yield and grain number of 72 soybean cultivars in China. We derived the parameters controlling soybean flowering and maturity time in the lack of data from contrasting environments, then tested APSIM to simulate LAI, biomass and grain yield. Our results show that once phenology is correctly simulated, APSIM was able to capture the LAI and biomass growth dynamics of multiple cultivars and across different years. Our data showed a strong correlation of grain yield with grain number, but not with grain size. Future model improvement could include the simulation of grain setting (grain number and grain filling rate) and their difference between cultivars so that yield difference can be simulated. Further scenario modelling demonstrated that APSIM also captured the genotype by environment interactions as they impact on yield. The derived parameters for 72 soybean cultivars provide the first data set in APSIM for improved modelling of soybean genotypes in China and beyond, adding to the current APSIM validation database of soybean. This also formed the basis for future modelling of intercropping systems with soybean, e.g. maize/soybean intercropping. [ABSTRACT FROM AUTHOR]

[Display omitted] • The water extract of Sojae semen germinatum (SSG) improved BPH-associated overactive bladder. • Multi-omics provided insights and discovered the important role of the arachidonic acid metabolism pathway in the treatment effect of SSG. • SSG mainly reduced detrusor overactivity by down-regulation of PGE2/EP1/PLCβ2/p-MLC signaling pathway. Sojae semen germinatum (SSG) is derived from mature soybean seeds that have been germinated and dried, typically with sprouts measuring approximately 0.5 cm in length. SSG is traditionally known for its properties in clearing heat and moisture. Nevertheless, limited information was reported on the effects and mechanisms of SSG in alleviating urinary symptoms. This study employed urodynamic parameters to investigate the therapeutic effect of SSG water extract on overactive bladder (OAB) in the rat model with benign prostatic hyperplasia. Through a combination of transcriptomic and metabolomic analyses, the pathways and key proteins of the SSG treatment for OAB were identified and validated by ELISA and Western blotting. Furthermore, network pharmacology elucidated the roles of SSG's isoflavones acting on the target which was identified by above-mentioned multi-omics analysis. Our results indicate that SSG water extract significantly mitigated OAB by down-regulating the PGE2/EP1/PLCβ2/p-MLC signaling pathway. It was speculated that the active ingredient in the SSG on EP1 was genistein. This study provided valuable insights into the molecular mechanisms of SSG water extract, emphasizing the multi-target characteristics and critical pathways in improving OAB. Furthermore, this study contributes to the potential utilization of SSG as a functional food. [ABSTRACT FROM AUTHOR]

• Ni-Co synergetic effect promotes the ring-opening reaction significantly. • The presence of Ni in CoAl oxides restrains the growth of metal particles. • The adsorption configuration of furfuryl alcohol affects the products distribution. 1,5-pentanediol (1,5-PeD) is a value-added chemical that can be produced from furfuryl alcohol (FFA) via selective scission of C O bond coupled with following hydrogenation reaction. In this work, a series of hydrotalcite-derived Ni-Co-Al catalysts with different Ni/Co ratios were evaluated for FFA upgrading to 1,5-PeD at a temperature range of 413–473 K and hydrogen pressure from 2 to 5 MPa. The catalytic performance and reaction products distribution were found to be highly sensitive to the Ni/Co ratio in the catalysts as well as reaction conditions. The highest catalytic activity was achieved with the Ni-Co-Al catalyst at a Ni/Co atomic ratio of 1:11 (Ni 1 Co 11 Al), which attained a 1,5-PeD yield of 42.5 % after 4 h of reaction. The presence of Ni in the Ni 1 Co 11 Al catalyst could significantly improve the BET surface area and suppress the growth of metal nanoparticles, leading to its superior catalytic stability in 5 runs. According to the characterization results, it was supposed that hydrogen spillover occurred from the surface of Ni to that of Co species, which was expected to enhance the hydrogen adsorption/activation capability and surface H concentration. The rapid H transfer was beneficial to the hydrogenolysis of furan ring and in situ hydrogenation of reaction intermediates, thus greatly facilitating the activity of the catalyst. Based on the experimental and characterization results, a plausible reaction mechanism was proposed for the selective generation of 1,5-PeD from FFA over the Ni 1 Co 11 Al catalyst. The results attained in this paper demonstrated the possibility of using non-precious mixed metal catalyst for FFA upgrading, and could provide useful insights for the design of efficient catalysts. [ABSTRACT FROM AUTHOR]

A nano-scale electrochemical sculpture (NES) method has been developed to enhance the bonding strength of fiber metal laminates (denoted as FMLs-NES). The influence of NES surface treatments on the low velocity impact response and static mechanical behavior of FMLs was systematically investigated and compared with traditional surface treatments such as mechanical polishing and NaTESi anodizing (denoted respectively as FMLs-PS and FMLs-NaTESi). The examination of the damage area and energy absorption under different impact energy levels revealed that the FMLs-NES specimen exhibited the smallest damage area and energy absorption while maintaining the structural integrity after impact. Finite element simulations were conducted to inform the impact damage progression and failure mechanisms, the results indicate that the interfacial failure mainly occurred between the middle titanium sheet and the bottom 90° fiber layer and propagated from the long edge to the center of FMLs. The experimentally validated finite element model can also be employed to optimize the stacking sequence of FMLs and to predict the residual strength after impact, where the FMLs-NES showed the highest residual strength. [Display omitted] [ABSTRACT FROM AUTHOR]

Shade avoidance syndrome (SAS) is an important measure of how plants respond to shade. Shade conditions are characterized by low light density and low red-to-far-red light (R/FR) ratio. However, low light intensity and low R/FR ratio play considerable and diverse roles in SAS. In the present study, soybean plants were grown in the presence and absence of additional FR at two light levels to investigate the different effects on soybean plants. Compared with normal light intensity, net photosynthetic rate significantly decreased in low light, but increased in low R/FR ratio. Chlorophyll a fluorescence transient curves showed that the absorption of light flux increased under low light intensity and low R/FR ratio, whereas the number of photo reaction centers decreased under low light intensity. In addition, the content of porphyrins and chlorophyll metabolites (magnesium protoporphyrin IX, protochlorophyllide, and chlorophyll a and b) was significantly enhanced by low light intensity and the relative gene expression levels of protoporphyrin IX magnesium chelatase , chlorophyll a oxygenase and protochlorophyllide oxidoreductases involved in the porphyrin pathway were significantly increased. The inhibitory effects of low light on the photosynthetic rate and biomass of soybean plants were alleviated by a low R/FR ratio. A low R/FR ratio optimized light capture and achieved efficient light energy utilization under low light intensity by fine-tuning the chlorophyll level and the relative gene expression level of critical chlorophyll biosynthesis-related enzymes. • Far-red light can improve the net photosynthetic rate of soybean under low light intensity. • Low R/FR ratio optimizes light energy capture and distribution under low light intensity. • Low R/FR ratio can be fine-tuned for accumulation of chlorophyll under low light intensity by decreasing the relative expression of CHL and POR. [ABSTRACT FROM AUTHOR]

The maize-soybean intercropping system has become increasingly popular in many areas of the world, particularly in China, due to its high productivity and the harvest of two different grains. While efforts have been made to maintain the yield of the taller maize crop, there is limited understanding of how the morphology, growth and yield of the lower soybean crop changes in response to the shading by maize. We therefore conducted a three-year field experiment from 2013 to 2015 to investigate the changes in light environment, growth of individual organs, biomass, and grain yield of soybean under two intercropping patterns (1M1S, one row of maize with one row of soybean; 2M2S, two rows of maize with two rows of soybean) as compared to monoculture. Our results showed that at soybean flowering stage, the R:FR ratio at the top of soybean canopy was reduced 17–21% more than the photosynthetically active radiation (PAR) under intercropping compared to monoculture, with 15–19% more reduction under 1M1S than 2M2S. This led to increased internode lengths, plant height and specific leaf area (SLA), but reduced branching of soybean plants under intercropping. These morphological changes enabled the crop to intercept relatively more light and the shading also increased the light use efficiency (LUE) of soybean. However, these positive responses were not able to compensate the effect of reduced leaf area (due to smaller leaf size and less branching) and total light interception, leading to reduced biomass and grain. The reduction in grain yield was mainly caused by the reduced number of grains (particularly on the middle nodes) produced by the intercropped soybean plants, while the grain size remained unchanged. The data and results of this study may be used to develop and parameterize crop models for simulating development and growth of soybean crop in response to changes in the light environment under intercropping. [ABSTRACT FROM AUTHOR]

Maize–soybean strip intercropping can effectively alleviate arable land competition, improve land output, and be conducive to the sustainable development. The key to achieve these advantages is to stabilize the maize yield. Suitable narrow row spacing could maximize the benefit of maize–soybean strip intercropping, and an increasing bandwidth with suitable narrow row spacing is beneficial to the mechanized production of soybean. In practice, to ensure the maize yield in additive maize strip intercropping, maize plant spacing decreases and intraspecific competition intensifies as the bandwidth increases. However, interspecific interactions have been the primary focus of studies because of the better rhizosphere nitrogen fixation ability of soybean and the activation of maize rhizosphere nutrients. Therefore, it is particularly urgent to identify the trade-offs between intraspecific competition and interspecific interactions in maize and the regulatory effects on maize yield. Field experiments were conducted from 2017 to 2020 to analyze the results of interindividual competition in maize and interactions with soybeans under different bandwidths. It was found that maize biomass and yield at the maturity stage decreased by 8.0% and 6.4%; 20.5% and 19.4%; and 28.7% and 44.1% from 2 m to 2.8 m, respectively, but the biomass proportion in ears showed no significant difference. Intraspecific competition of maize was weakened by special promotion in intercropping, but stable yield was achieved only at 2 m. In response to suitable competition, maize roots can flourish only on the basis of ensuring aboveground biomass. The results revealed that the primary negative determinant of maize yield was intraspecific aboveground competition and strengthening intraspecific competition reduced biomass accumulation without altering the allocation ratio to the ear. We concluded that maize yield was guaranteed at 2 m due to the special strip planting design compensated for the enhanced intraspecific competition of maize aboveground parts in the additive maize–soybean strip intercropping system. • Lower intraspecific competition was a driver of maize yield under different bandwidths. • The aboveground part of maize contributed more to the yield advantage than the underground part. • Decrease in biomass, not the proportion of partitioning to the ear, affected the maize yield. [ABSTRACT FROM AUTHOR]

• This work estimates maize grain yield and protein using physiological parameters. • Water and nitrogen availability affect maize grain yield and protein content. • Physiological parameters of maize are estimated using RVI and wavelet methods. • Maize productivity model integrates canopy spectra and physiological parameters. • The results are promising for the operational estimation of maize production. Predicting grain yield and protein content of maize using spectral reflectance data is very important for improved agricultural production. In this study, we predicted the grain yield and protein content of maize grown under different irrigation and nitrogen levels in 2018 and 2019 based on canopy spectral reflectance measurements at the V6 (sixth leaf), VT (tassel), and R2 (blister) stages. We developed a predictive approach, namely, spectral reflectance–physiological parameters–productivity, to predict grain yield and protein content on maize crop. First, the quantitative relationships between grain yield and protein content and physiological parameters (canopy chlorophyll content [CCC], leaf carbon accumulation [LCA], leaf nitrogen content [LNC], and leaf nitrogen accumulation [LNA]) were analysed. Then, vegetation indices (VIs) and wavelet features based on spectral reflectance were used to establish estimation models for physiological parameters. The physiological parameters were used as a bridge to connect the spectral reflectance data with grain yield and protein content. The purpose was to establish spectral inversion models to indirectly estimate grain yield and protein content. Results showed that grain yield had a significant linear relationship with CCC and LCA. In addition a grain protein content and LNC and LNA were also significantly related under different water, and nitrogen availability. The physiological parameter models with ratio vegetation indices (RVI), biorthogonal 3.3 (bior3.3), and reverse biorthogonal 1.5 (rbio1.5) were reliable in terms of predictability and applicability. Independent data verification suggested that grain yield was predicted using RVI 769,758 (R2 = 0.773, RMSE = 2.509) in water availability, rbio1.5 781,29 (R2 = 0.744, RMSE = 2.850) in nitrogen availability, and rbio1.5 772,11 (R2 = 0.506, RMSE = 2.297) in water–nitrogen availability. In addition, the grain protein content was predicted using RVI 793,757 (R2 = 0.704, RMSE = 0.744) in water availability, bior3.3 743,19 (R2 = 0.717, RMSE = 0.957) in nitrogen availability, and RVI 492,418 (R2 = 0.715, RMSE = 1.224) in water–nitrogen availability. Therefore, maize grain yield and protein content can be accurately predicted using our modelling approach. [ABSTRACT FROM AUTHOR]