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The operational performance of cereal seeding machinery influences the yield and quality of cereals. In this article, we review the existing literature on intelligent technologies for cereal seeding machinery, encompassing active controllable seeding actuators, intelligent seeding rate control, and intelligent seed position control systems. In this manuscript, (1) the characteristics and innovative structures of existing motor-driven seed-metering devices and ground surface profiling mechanisms are expounded; (2) state-of-the-art detection principles and applications for soil property sensors are described based on different soil properties; (3) optimal seeding rate decision approaches based on soil properties are summarized; (4) the research state of seeding rate measuring and control technologies is expounded in detail; (5) trajectory control methods for seeding machinery and seeding depth control systems are described based on measurement and control principles; and (6) the present state, limitations, and future development directions of intelligent cereal seeding machinery are described. In the future, more advanced multi-algorithm and multi-sensor fusion technologies for soil property detection, optimal seeding rate decisions, seeding rates, and seed position control are likely to evolve. This review not only expounds the latest studies on intelligent actuating, sensing, and control technologies for intelligent cereal seeding machinery, but also discusses the shortcomings of existing intelligent seeding technologies and future developing trends in detail. This review, therefore, offers a reference for future research in the domain of intelligent seeding machinery for cereals.

Adoption of appropriate agronomic practices, such as optimum seeding and nitrogen (N) rates, in synchronization with proper water management practice could help improve yield, water productivity and N use efficiency (NUE) of rice ( Oryza sativa L.). Field experiments were conducted at the research farm of the Asian Institute of Technology during the dry seasons (November–March) of 2017–2018 and 2018–2019 to evaluate the effects of seeding (S) (95 [S 95 ], 125 [S 125 ] and 155 [S 155 ] kg ha −1 ) and N (0 [N 0 ], 60 [N 60 ] and 120 [N 120 ] kg ha −1 ) rates under different water regimes (continuous flooding [CF] and safe alternate wetting and drying [AWD15]) on yield, water productivity and NUE of wet direct-seeded rice. Application of 120 kg N ha −1 (N 120 ) resulted in the highest grain yield and water productivity (by 76% and 78%, respectively, compared with N 0 ), which were statistically similar with N 60 . Less plant population in lower seeding rates (S 95 and S 125 ) provided better results in terms of vegetative and reproductive growth, grain yield and water productivity. Rice grown under AWD15 resulted in statistically similar grain yield with rice maintained under CF, but there was 40–44% more water savings depending on seeding rates and 68% higher water productivity in AWD15-treated plots. Improving sink capacity and dry matter accumulation is key to ensuring better grain yields even with reduced N and seeding rates under AWD15. A stronger relationship between grain yield and spikelet number panicle −1 as well as between shoot dry matter and spikelet number panicle −1 was observed under CF (r = 0.61 and r = 0.57, respectively) compared with AWD15 (r = 0.45 and r = 0.41, respectively). N 60 had significantly higher partial factor productivity (64.6) of applied N than N 120 (36.4). S 95 and S 125 resulted in a significant improvement in NUE compared with S 155 . This result suggests that desirable grain yield and water productivity as well as better NUE could be achieved by decreasing N rate from 120 to 60 kg ha −1 , and thus significant reduction in fertilizer input cost could be possible along with environmental benefits. In addition, decreasing seeding rate coupled with AWD15 is recommended to reduce the input cost and total water input to make the wet direct-seeded rice cultivation system more sustainable and profitable.

Cancer metastasis requires the transient activation of cellular programs enabling dissemination and seeding in distant organs 1 . Genetic, transcriptional and translational heterogeneity contributes to this dynamic process 2 , 3 . Metabolic heterogeneity has also been observed 4 , yet its role in cancer progression is less explored. Here we find that the loss of phosphoglycerate dehydrogenase (PHGDH) potentiates metastatic dissemination. Specifically, we find that heterogeneous or low PHGDH expression in primary tumours of patients with breast cancer is associated with decreased metastasis-free survival time. In mice, circulating tumour cells and early metastatic lesions are enriched with Phgdh low cancer cells, and silencing Phgdh in primary tumours increases metastasis formation. Mechanistically, Phgdh interacts with the glycolytic enzyme phosphofructokinase, and the loss of this interaction activates the hexosamine–sialic acid pathway, which provides precursors for protein glycosylation. As a consequence, aberrant protein glycosylation occurs, including increased sialylation of integrin α v β 3 , which potentiates cell migration and invasion. Inhibition of sialylation counteracts the metastatic ability of Phgdh low cancer cells. In conclusion, although the catalytic activity of PHGDH supports cancer cell proliferation, low PHGDH protein expression non-catalytically potentiates cancer dissemination and metastasis formation. Thus, the presence of PHDGH heterogeneity in primary tumours could be considered a sign of tumour aggressiveness. PHDGH heterogeneity in primary tumours could be a sign of tumour aggressiveness.

Metastasis is the primary cause of cancer-related deaths, but the natural history, clonal evolution and impact of treatment are poorly understood. We analyzed whole-exome sequencing (WES) data from 457 paired primary tumor and metastatic samples from 136 patients with breast, colorectal and lung cancer, including untreated ( n  = 99) and treated ( n  = 100) metastases. Treated metastases often harbored private ‘driver’ mutations, whereas untreated metastases did not, suggesting that treatment promotes clonal evolution. Polyclonal seeding was common in untreated lymph node metastases ( n  = 17 out of 29, 59%) and distant metastases ( n  = 20 out of 70, 29%), but less frequent in treated distant metastases ( n  = 9 out of 94, 10%). The low number of metastasis-private clonal mutations is consistent with early metastatic seeding, which we estimated occurred 2–4 years before diagnosis across these cancers. Furthermore, these data suggest that the natural course of metastasis is selectively relaxed relative to early tumorigenesis and that metastasis-private mutations are not drivers of cancer spread but instead associated with drug resistance. Analysis of whole-exome sequencing data from paired primary tumors and metastases from patients with breast, colorectal and lung cancer identifies clonal remodeling associated with therapy and few metastasis-private clonal mutations, consistent with early metastatic seeding.

During drought, xylem sap pressures can approach or exceed critical thresholds where gas embolisms form and propagate through the xylem network, leading to systemic hydraulic dysfunction. The vulnerability segmentation hypothesis (VSH) predicts that low-investment organs (e.g. leaf petioles) should be more vulnerable to embolism spread compared to high-investment, perennial organs (e.g. trunks, stems), as a means of mitigating embolism spread and excessive negative pressures in the perennial organs. We tested this hypothesis by measuring air-seeding thresholds using the single-vessel air-injection method and calculating hydraulic safety margins in four northern hardwood tree species of the northeastern United States, in both saplings and canopy height trees, and at five points along the soil–plant–atmosphere continuum. Acer rubrum was the most resistant to air-seeding and generally supported the VSH. However, Fagus grandifolia, Fraxinus americana and Quercus rubra showed little to no variation in air-seeding thresholds across organ types within each species. Leaf-petiole xylem operated at water potentials close to or exceeding their hydraulic safety margins in all species, whereas roots, trunks and stems of A. rubrum, F. grandifolia and Q. rubra operated within their safety margins, even during the third-driest summer in the last 100 yr.

Precision agriculture techniques, such as variable rate seeding (VRS) and hybrid switching, play an important role in optimizing crop yield and reducing input costs. This study evaluates the effectiveness of hybrid switching and the application of VRS technology in maize production, focusing on the accuracy of seeding rate and hybrid placement under varying field conditions. Conducted over two years, the research compares the performance of a precision planting system in flat (2023) and hilly (2024) terrain in north-eastern Hungary. The study examines seed placement uniformity, furrow quality and seed drop rates, with a focus on how terrain affects the success of these operations. A data analysis shows that hybrid switching and VRS result in better seed placement and more uniform furrows in downhill operations, with lower seed drop rates compared to uphill operations. In addition, the paper discusses the importance of accurate seeding equipment calibration and data cleaning. The findings highlight the critical need for accuracy and reliability in precision agriculture and provide insights to improve future crop management strategies and ensure sustainable farming practices. The study evaluates the accuracy of hybrid switching in maize across different terrain types and its impact on operational efficiency. The results show variation in hybrid switching distances, with an average transition length of 5.1 m on flat terrain, 5.80 m on uphill, and 4.22 m on downhill. The longest transitions occurred on uphill terrain due to increased mechanical adjustment delays, while the shortest transitions were observed on downhill slopes where seed flow remained more stable. The results highlight the importance of terrain-adaptive control mechanisms in precision planting systems to minimize transition delays, improve seed placement accuracy, and increase overall yield potential.

Ovarian cancer (OC) is the most lethal gynecological malignancy worldwide, characterized by heterogeneity at the molecular, cellular and anatomical levels. Most patients are diagnosed at an advanced stage, characterized by widespread peritoneal metastasis. Despite optimal cytoreductive surgery and platinum-based chemotherapy, peritoneal spread and recurrence of OC are common, resulting in poor prognoses. The overall survival of patients with OC has not substantially improved over the past few decades, highlighting the urgent necessity of new treatment options. Unlike the classical lymphatic and hematogenous metastasis observed in other malignancies, OC primarily metastasizes through widespread peritoneal seeding. Tumor cells (the “seeds”) exhibit specific affinities for certain organ microenvironments (the “soil”), and metastatic foci can only form when there is compatibility between the “seeds” and “soil.” Recent studies have highlighted the tumor microenvironment (TME) as a critical factor influencing the interactions between the “seeds” and “soil,” with ascites and the local peritoneal microenvironment playing pivotal roles in the initiation and progression of OC. Prior to metastasis, the interplay among tumor cells, immunosuppressive cells, and stromal cells leads to the formation of an immunosuppressive pre-metastatic niche in specific sites. This includes characteristic alterations in tumor cells, recruitment and functional anomalies of immune cells, and dysregulation of stromal cell distribution and function. TME-mediated crosstalk between cancer and stromal cells drives tumor progression, therapy resistance, and metastasis. In this review, we summarize the current knowledge on the onset and metastatic progression of OC. We provide a comprehensive discussion of the characteristics and functions of TME related to OC metastasis, as well as its association with peritoneal spread. We also outline ongoing relevant clinical trials, aiming to offer new insights for identifying potential effective biomarkers and therapeutic targets in future clinical practice.

Seeding strategies have strong influences on the success of viral marketing campaigns, but previous studies using computer simulations and analytical models have produced conflicting recommendations about the optimal seeding strategy. This study compares four seeding strategies in two complementary small-scale field experiments, as well as in one real-life viral marketing campaign involving more than 200,000 customers of a mobile phone service provider. The empirical results show that the best seeding strategies can be up to eight times more successful than other seeding strategies. Seeding to well-connected people is the most successful approach because these attractive seeding points are more likely to participate in viral marketing campaigns. This finding contradicts a common assumption in other studies. Well-connected people also actively use their greater reach but do not have more influence on their peers than do less well-connected people.

Invasive annual grasses alter fire regimes in shrubland ecosystems of the western USA, threatening ecosystem function and fragmenting habitats necessary for shrub‐obligate species such as greater sage‐grouse. Post‐fire stabilization and rehabilitation treatments have been administered to stabilize soils, reduce invasive species spread and restore or establish sustainable ecosystems in which native species are well represented. Long‐term effectiveness of these treatments has rarely been evaluated. We studied vegetation at 88 sites where aerial or drill seeding was implemented following fires between 1990 and 2003 in Great Basin (USA) shrublands. We examined sites on loamy soils that burned only once since 1970 to eliminate confounding effects of recurrent fire and to assess soils most conducive to establishment of seeded species. We evaluated whether seeding provided greater cover of perennial seeded species than burned–unseeded and unburned–unseeded sites, while also accounting for environmental variation. Post‐fire seeding of native perennial grasses generally did not increase cover relative to burned–unseeded areas. Native perennial grass cover did, however, increase after drill seeding when competitive non‐natives were not included in mixes. Seeding non‐native perennial grasses and the shrub Bassia prostrata resulted in more vegetative cover in aerial and drill seeding, with non‐native perennial grass cover increasing with annual precipitation. Seeding native shrubs, particularly Artemisia tridentata, did not increase shrub cover or density in burned areas. Cover of undesirable, non‐native annual grasses was lower in drill seeded relative to unseeded areas, but only at higher elevations. Synthesis and applications. Management objectives are more likely to be met in high‐elevation or precipitation locations where establishment of perennial grasses occurred. On lower and drier sites, management objectives are unlikely to be met with seeding alone. Intensive restoration methods such as invasive plant control and/or repeated sowings after establishment failures due to weather may be required in subsequent years. Managers might consider using native‐only seed mixtures when establishment of native perennial grasses is the goal. Post‐fire rehabilitation provides a land treatment example where long‐term monitoring can inform adaptive management decisions to meet future objectives, particularly in arid landscapes where recovery is slow.

Due to the lack of an exact simulation model for spinach seeds, existing seed-metering devices exhibit poor seeding performance and struggle to achieve precise seeding of two seeds per seed-metering hole. This study proposes a method for calibrating discrete element parameters of spinach seeds and develops a seed-metering device with rectangular seed-metering holes tailored to the two-seeds-per-hole requirement. Firstly, a spinach seed discrete element model was constructed. Based on the Box-Behnken Design experimental scheme, simulations of angle of repose and fluidity, combined with physical of angle of repose (38.27°) and physical mass flow rate (18.60 g/s), were used to calibrate contact parameters: (1) between spinach seed models (coefficient of restitution: 0.385; coefficient of static friction: 0.481; coefficient of rolling friction: 0.042); and (2) between seed models and PVC plate (coefficient of restitution: 0.339; coefficient of static friction: 0.600; coefficient of rolling friction: 0.408). Subsequently, simulated and physical bulk density tests were conducted to verify the validity of the established spinach seed model. Guided by the agronomic requirements for spinach seed planting, the range of dimensional parameters for the seed-metering holes was defined. Using the Box-Behnken Design, simulated seeding tests were performed to optimize the device’s structural parameters (hole depth, hole length, hole width, and seed-filling angle), resulting in optimal values of 2.52 mm, 3.67 mm, 5.15 mm, and 37.99°, respectively. Finally, physical seeding tests were conducted, achieving a qualified seeding rate of 92.23% at a seeding speed of 10 r/min. These results confirm the design accuracy and high operational efficiency of the device. This study lays a foundation for the overall design of future spinach planters.