Search Results (420)

Balancing path-following accuracy and error convergence with graceful motion in steering control is challenging due to the competing nature of these requirements, especially across a range of operating speeds and conditions. This paper demonstrates that an integrated, multi-tiered steering controller considering slip in kinematic control, dynamic control, and steering actuator rate commands achieves accurate and graceful path following. Kinematic and dynamic models are adapted to include slip. A path-following kinematic controller is then derived using a continuous, time-varying, and speed-based variable-structure controller (VSC) to balance safe and graceful motion with robust error convergence. Yaw rate commands from the kinematic controller are nested in a backstepping slip–yaw dynamic tracking controller to generate steering rate commands. A high-gain observer (HGO) estimates the sideslip and yaw rate, which are used in sensor-based output feedback control. Stability analysis of the output feedback controller is provided, and peaking is resolved. The work focuses on lateral control alone so that the steering controller can be combined with other speed controllers. Field results demonstrate gracefulness and accuracy along complex paths in variable terrain, in different weather conditions, and with perturbations. Full article

Sarcocystis is a genus of heteroxenous, globally distributed apicomplexan parasites found in reptiles, birds, and mammals. Typically, sarcocysts develop in muscles of intermediate hosts, and oocysts sporulate in intestines of definitive hosts. The parasite’s life cycle is based on prey–predator relationships and usually involves two distinct host species. However, some Sarcocystis spp. can complete their full development within a single host species. Brown rats (Rattus norvegicus) are invasive, synanthropic, highly adaptable rodents that are true omnivores and opportunistic feeders. Therefore, it is possible that they can act as definitive hosts of Sarcocystis parasites. This study provides the first comprehensive assessment of Sarcocystis protists in brown rat intestinal samples under natural conditions, combining microscopy and molecular analyses. Of 27 brown rats investigated, 25.9% (7/27) of animals harbored oocysts/sporocysts of Sarcocystis spp. Based on nested PCR and sequencing of four genetic loci (18S rRNA, 28S rRNA, ITS1, and cox1), 59.3% of samples were positive for Sarcocystis spp. Parasites identified were genetically similar to Sarcocystis spp. using bird–bird, bird–Carnivora, rodent–Carnivora, or ungulate–Carnivora as their intermediate–definitive hosts. The present study suggests that synanthropic rodents may facilitate cross-ecosystem transmission of these parasites, increasing infection pressure on livestock, companion animals, and wildlife in human-dominated environments. Future molecular and dietary ecological studies are needed to assess the role of synanthropic and opportunistic hosts, such as the brown rat, in the transmission of Sarcocystis spp. Full article

Pesticides remain among the most significant threats to biodiversity and natural ecosystems. Non-invasive methods, such as the analysis of bird faeces, have shown great potential for detecting pesticide exposure. In this study with a new approach, we analysed faecal sacs from nestlings of Blue tits (Cyanistes caeruleus) and Great tits (Parus major) to gain deeper insights into pesticide contamination during the breeding period. Samples were collected from three distinct sites near Münster, Germany. In total, we detected 65 substances from 57 different pesticides, as well as caffeine, with pesticides present in 16.07% of the 168 samples. Concentrations varied between species and sites and were higher for fungicides and insecticides in nests located closer to agricultural fields. While no direct effects on reproductive success were found, our results underscore the potential of faecal sac analysis as a valuable tool for spatially resolved pesticide monitoring. The novel, non-invasive approach to pesticide monitoring offers crucial exposure data on juvenile birds during their sensitive breeding period. Full article

The impact of tourism on Magellanic penguins (Spheniscus magellanicus) in Patagonia is a complex issue that requires a balanced approach between conservation and sustainable tourism development. While tourism in the region can bring significant economic benefits, it can also have a negative impact on the penguins by disrupting nesting behavior and chick rearing, and even increasing the risk of disease and predation. We examined a comparative analysis of scientific papers on the impact of tourism on Magellanic penguins in two breeding colonies in Argentinean Patagonia, which have been visited for 10 to 50 years and whose visitor numbers range from 10,000 to 120,000 per year. We analyzed different physiological parameters (i.e., immunological, hematological, biochemical, and stress parameters) and behavioral respond (alternate head turns) in adult birds and chicks in these colonies. Although the results suggest that Magellanic penguins have adapted well to the presence of tourists in their breeding colonies, we documented changes in certain physiological parameters that indicate chronic stress due to high exposure to tourism. It is important to promote sustainable tourism in Patagonia that not only minimizes these negative impacts but also improves the protection of the penguins and their habitat. This includes the creation of new nature reserves, environmental education, and the regulation of tourism activities. Implementing responsible tourism practices can ensure economic benefits while protecting the well-being and health of penguin populations. The combination of increased tourist awareness and concrete conservation measures can protect not only the Magellanic penguins but also the natural wealth of the entire Patagonia region. Full article

Nest architecture and surrounding habitat features can strongly influence the reproductive success of cavity-nesting birds; however, quantitative data from natural environments remain limited. We examined how nest structure and surrounding habitat features correlate with reproduction in the small bee-eater (Merops orientalis). A total of 38 natural nests were monitored during the breeding season. The Conway–Maxwell–Poisson model showed that cavity depth was a significant positive predictor of clutch size (β = 0.46 ± 0.22 SE, p = 0.036), whereas entrance diameter and nest height were not significantly related. Principal component analysis (PCA) of standardized cavity dimensions (cavity depth, entrance diameter, and nest height) showed that nest height (captured by PC2) was strongly associated with higher breeding success (OR = 0.002, p = 0.021), whereas overall cavity size (PC1) had a weaker, marginally positive correlation (OR = 3.87, p = 0.09). Habitat distance variables showed only weak, non-significant trends after accounting for multicollinearity. Nest structural traits explained more variation in reproductive performance than landscape variables (pseudo-R² = 0.80 for clutch size; 0.59 for breeding success). Field monitoring of 38 nests showed a mean clutch size of 3.9 eggs, an overall hatching success of 77.5%, and a fledging success of 51.2%, yielding a 37.1% breeding success. Our results highlight the importance of conserving sandy streambanks and mitigating human disturbance in proximity to active nests to conserve breeding success in small bee-eaters. As these findings were based on one site and a single breeding season, broader generalizations will require replication across additional years and locations. Full article

Rapid global urbanization has led to the loss and degradation of many natural habitats, causing numerous bird species to inhabit and breed in cities. Here we investigated the influence of multiple factors on the number of chicks of the four common waterbird species, from Anatidae [Mallard (Anas platyrhynchos), Mute Swan (Cygnus olor)] and from Rallidae [Eurasian Coot (Fulica atra), Common Moorhen (Gallinula chloropus)], nesting in Gdańsk (Poland) in 2020 and 2021. We found that the harsh winter before the 2021 season may have resulted in a lower number of chicks in rallids. Rainfall and higher temperatures during breeding season increased the number of rallids’ chicks. Larger waterbodies were associated with a lower number of chicks (except for Moorhen). However, a longer shoreline was related to a higher number of chicks of all species. The Normalized Difference Moisture Index, indicating absence of urban fabric, positively impacted the number of chicks of all species, except for Mallard. The distance of waterbody from areas with varying degrees of urbanization had a diverse effect on the number of chicks of each species, except for Swan. Our results emphasize the importance of urban reservoirs for breeding birds and highlight the need to preserve natural features, such as allowing bank vegetation and reeds to grow, to provide nesting sites and shelter. Full article

Precision livestock farming (PLF), by integrating multimodal sensor data, provides opportunities to enhance welfare monitoring and management in small ruminants. This study evaluated whether environmental, physiological, and behavioral measurements—including the temperature–humidity index (THI), carbon dioxide (CO₂) and ammonia (NH₃) concentrations measured at the barn level, body condition score (BCS), rectal and ocular temperatures, GPS-derived locomotion metrics, accelerometry data, and fixed animal traits—can serve as key predictors of welfare and productivity in dairy sheep. Data were collected from 90 ewes: all animals underwent the same repeated welfare assessments, while 30 of them were additionally equipped with GPS–accelerometer sensor collars; environmental conditions were continuously recorded for the entire flock, generating 773 complete multimodal records. All predictive models were developed using data from all 90 ewes; collar-derived behavioral variables were included only for individuals equipped with GPS–accelerometer collars. Nine regression methods (linear regression (LR), partial least square regression (PLSR), elastic net (EN), mixed-effects models, random forest (RF), extreme gradient boosting (XGBoost), support vector regression (SVR), neural networks (multilayer perceptron, MLP), and an ensemble of RF–XGBoost–EN were evaluated using a combination of nested cross-validation (CV) and leave-one-animal-out CV (LOAOCV) to ensure robustness and generalization at the individual animal level. Nonlinear models—particularly RF, XGBoost, SVR, and the ensemble—consistently delivered superior performance across traits. For behavioral (e.g., daily distance movement) and thermal indicators (e.g., medial canthus temperature), the highest predictive capacity (R² ≈ 0.60–0.70) was achieved, while moderate predictive capacity (R² ≈ 0.40–0.50 and ≈0.35–0.45), respectively, was observed for respiratory rate and milk yield, reflecting their multifactorial nature. Feature importance analyses underscored the relevance of THI, CO₂, NH₃, concentrations, and BCS across results. Overall, these findings demonstrate that multimodal sensor fusion can effectively support the prediction of welfare and productivity indicators in intensively reared dairy sheep and emphasize the need for larger and more diverse datasets to further enhance model generalizability and model transferability. Full article

Urban space exhibits marked heterogeneity in both form and function, yet how urban functions align with multilevel street structures remains insufficiently understood. This study investigates the coupling between street hierarchy and urban functions in Shenzhen through two complementary representations: (1) the relationship between street connectivity and POIs located near each street, and (2) the relationship between street nodes and POIs contained within street-node-based hotspots. Both datasets were hierarchically partitioned using head/tail breaks to reveal intrinsic scaling structures. Power-law detection shows that natural streets and hotspot clusters follow heavy-tailed distributions, forming nested living structures. The exponents for node- and POI-based clusters fall within the typical range of 2.0–2.2, whereas exponents for street connectivity and street-based POIs are higher, indicating stronger heterogeneity. Correlation analyses reveal consistent positive associations between POIs and street connectivity across all levels, with the strongest relationships in mid- to upper-level substructures. Toward finer levels, correlations weaken and become increasingly nonlinear, reflecting growing spatial irregularity. These findings demonstrate that Shenzhen’s urban functions are coherently organized along its street hierarchy, highlighting the fundamental role of multilevel street configurations in shaping functional spatial patterns. Full article

The Krabi mouth-brooding fighting fish, Betta simplex Kottelat, 1994, is a critically endangered and endemic fish species in Krabi province, Southern Thailand. Little information is available on its reproductive ecology and early developmental morphology, which are essential for studying its conservation. Generally, B. simplex is considered an adaptable animal that can tolerate lower alkalinity and higher hardness compared to its natural environment conditions. In this study, wild broodstocks of B. simplex were collected from the reported type localities and bred in captivity under laboratory conditions for size-series collection. Some biological aspects of B. simplex in its natural environmental conditions were determined. We found that its flaring and mating behavior was similar to those of bubble-nesting fighting fish but did not involve bubble-nest building. The fertilized eggs and pre-flexion larvae were nurtured in the mouth cavity of parental males within 11–12 (mode = 11) days after fertilization (DAF). The first-release offspring developed to the post-flexion stage with a body size of 4.39 ± 0.01 mm of standard length (SL; n = 6) and then to the juvenile stage within 30 days after release with 11.72 ± 0.62 mm SL (n = 4). Thus, we propose the following linear regression equation for growth prediction by age (DAF) and body size (SL; mm): age = 0.2425 SL + 1.7036 (r² = 0.9549). The findings of this study will deepen our knowledge of the reproduction and ontogeny of B. simplex and contribute to its future conservation and management. Full article

Environmental degradation from rapid urbanization significantly threatens ecological resilience (ER). Nevertheless, accurately evaluating ER remains a persistent challenge. Prior studies’ limited attention to resilience’s cross-scale complexity has hindered evidence-based management. This study, based on long-term time series remote sensing and multi-source data, developed a cross-scale spatiotemporal ER analysis framework integrating landscape ecology and panarchy perspectives. A local “resistance–adaptation–recovery” substrate resilience evaluation was combined with telecoupling-based global network resilience to quantify multi-scale ER from 2000 to 2020. Key drivers across time scales were identified using a hybrid XGBoost–SHAP and genetic algorithm (GA)–optimized dynamic Bayesian network (DBN), and spatial optimization scenarios were simulated with patch-generating land use simulation (PLUS) model. ER decreased slightly from 0.4856 in 2000 to 0.4503 in 2020, with dynamic fluctuations across periods. A clear spatial pattern emerged, with higher ER in the east and lower in the west. Forest land contributed strongly to ER, while construction and cropland reduced it. Spatial composition factors—especially the proportions of forest and construction land—were dominant drivers, outweighing structural factors such as landscape pattern. DBN backward inference revealed nonlinear threshold effects among socio–natural–spatial drivers. Scenario-based simulations confirmed that regulating spatial composition via our optimization pathway can enhance ER. This is particularly effective when expanding forestland in mountainous regions while restraining the growth of built-up areas. This study proposes an integrated framework of “resilience assessment—driver analysis—spatial optimization,” which not only advances the theoretical basis for nested ER assessment but also offers a transferable approach for optimizing spatial patterns and sustainable land management, thereby enhancing ecological resilience in rapidly urbanizing regions. Full article

Pollinating insects are the most important pollinators in nature; they pollinate vegetables, fruits, oil crops, and wild plants, so that crop yields can be increased, wild plants can live and reproduce, and human food security and ecosystem stability are maintained. To identify the pollination network of plants–insects and the pollination service value in Hanzhong City, the methods of random net capture and transect counting in field work were used. The agricultural statistical data from Hanzhong City in 2023 was combined in the analysis. The results showed that Hanzhong City is rich in pollinator resources, with a total of 80 species of pollinators and 59 species of pollinating crops and wild nectar plants. The abundant pollinator resources provide sufficient pollination services for the production of local vegetables, fruits, and oil crops. The characteristics of the pollination networks are obvious, showing the structural characteristics of low connectivity, medium nesting, and low network specialization. In 2023, the pollination service value of pollinators in Hanzhong City was CNY 3524–4878 billion, accounting for 10.02–13.87% of the city’s agricultural output value of the year. Suggestions for the protection of pollinators in Hanzhong City: Reduce the use of pesticide, support beekeeping, intercrop nectar plants, and rationally plant crops. Full article

Predatory insects play a crucial role in maintaining ecosystem balance. Among them, members of the subfamily Zethinae, as natural enemies of herbivorous pests, have reproductive success closely linked to nest architecture, as this limits their prey items. We set up trap nests for Discoelius wangi Yamane, 1996 in a subtropical forest in southwestern China to investigate the effects of nest architecture parameters (number of intercalary cells, nest diameter, and vestibule length) on the number of brood cells, the quantity of male and female offspring, and emergence rate via generalized linear models and hierarchical partitioning. The results showed that for the number of nest cells, only the number of intercalary cells had a significant positive effect. For the quantity of male and female offspring, nest diameter, and the number of intercalary cells had significant positive effects on female offspring, while males were only significantly positively affected by the number of intercalary cells. For emergence rates, female emergence rate was marginally significantly affected by nest diameter, male emergence rate was marginally significantly affected by the number of intercalary cells, and total emergence rate was significantly influenced by vestibular length and the number of intercalary cells. This study indicates that D. wangi can adjust its nest characteristics to achieve precise regulation of reproductive performance. The results not only enhance our understanding of how human activities affect predatory insects in forest ecosystems but also provide a scientific basis for developing effective conservation and utilization strategies. Full article

Background: The minimized pan-coronavirus (CoV) vaccine-1 developed by our laboratory contained pDNA sequences of feline coronavirus serotype-1 (FCoV1) and SARS-CoV2 (SCoV2) spike B-cell epitopes plus FCoV/SCoV2-conserved, CoV-specific polymerase cytotoxic T-lymphocyte (CTL) epitopes formulated in lipid nanoparticle (LNP). Only FCoV2 infects feline cell lines needed for developing native challenge inoculum that causes feline infectious peritonitis (FIP). Hence, Pilot Study 1 evaluated the therapeutic efficacy and safety of the pan-CoV vaccine-1 in feline immunodeficiency virus (FIV)-infected cats, with or without FCoV1 coinfection. Pilot Study 2 evaluated the cross-protective effect of pan-CoV vaccines in specific-pathogen-free (SPF) cats against intranasal challenge with FIP virus serotype 2 (FIPV2). Methods: In Study 1, we vaccinated two FIV-infected cats (one negative and another positive for FCoV1 coinfection) intramuscularly twice with CTL epitopes-LNP vaccine and later twice with pan-CoV vaccine-1. Controls included two unvaccinated FIV-infected cats with or without FCoV1 coinfection. Study 2 assessed the sequential vaccinations of three pan-CoV vaccines in four SPF cats. The first two vaccinations were with pan-CoV vaccine-2, followed by pan-CoV vaccine-3 (twice), and lastly with pan-CoV vaccine-1 (once). Three SPF controls included two cats immunized with LNP and one lacking any immunization. Pan-CoV vaccine-2 contained pDNAs with modified FCoV1/SCoV2 B-cell epitopes plus CTL epitopes in LNP. Pan-CoV vaccine-3 contained only pDNAs with FCoV1 B-cell epitopes plus CTL epitopes in LNP. Results: Study 1 demonstrated no adverse effect with 25 μg and 50 μg CTL epitopes-LNP vaccine and 50 μg pan-CoV vaccine-1. However, 100 μg pan-CoV vaccine-1 caused fever 24 h later, which was resolved by a single Meloxicam treatment. Both vaccinees developed cross-FCoV2 neutralizing antibodies (XNAbs), immunoblot binding antibodies (bAbs) to FCoV1 receptor-binding domain (RBD), and T-cell responses to FCoV1 RBD, whereas one vaccinee also developed bAbs to SCoV2 RBD. Study 2 demonstrated no adverse effects after each vaccination. Three vaccinees developed low-titer XNAbs and bAbs to FCoV2 spike-2 by the fourth vaccination. Upon challenge, all cats developed FCoV2 NAbs and bAbs to FCoV2 nucleocapsid and RBD. High vaccine-induced T-cell responses to FCoV1 RBD and T-cell mitogen responses declined with an increase in responses to FCoV2 RBD at three weeks post-challenge. Two of the three controls died from FIP, whereas one vaccinee, with the lowest vaccine-induced immunity, died from skin vasculitis lesions and detection of FIPV2 infection by semi-nested RT-snPCR in feces. Conclusions: In Pilot Study 1, the pan-CoV vaccine-LNP dose of 50 μg had no adverse effects, but adverse effects were observed at 100 μg dose. In Pilot Study 2, the FCoV1-based B-cell vaccine(s) induced low levels of XNAbs against FIPV2 and delayed challenge infection against high-dose FIPV2. The high-dose FIPV2 infections in the vaccinated and control cats started to clear, by single housing at 23–26 weeks post-challenge, whereas two cats in Pilot Study 1 cleared natural FCoV1 transmission by 26 weeks post-infection. Full article

Sustainable finance exhibits non-linear dynamics, regime shifts, and distributional drift that challenge conventional forecasting, particularly in volatile emerging markets. Conventional models, which often overlook this structural complexity, can struggle to produce stable or reliable probabilistic forecasts. To address this challenge, this study introduces a complexity-aware forecasting framework that operationalizes information-theoretic meta features, Shannon entropy (SE), permutation entropy (PE) and Kullback–Leibler (KL) divergence to make Environmental, Social, and Governance (ESG) index forecasting more stable, probabilistically accurate, and operationally reliable. Applied in an emerging-market setting using Türkiye’s ESG index as a natural stress test, the framework was benchmarked against a macro-technical baseline with a calibrated XGBoost classifier under a strictly chronological, leakage-controlled nested cross-validation protocol and evaluated on a strictly held-out test set. In development, the framework achieved statistically significant improvements in both stability and calibration, reducing fold-level dispersion (by 40.4–66.6%) across all metrics and enhancing probability-level alignment with Brier score reduced by 0.0140 and the ECE by 0.0287. Furthermore, a meta-analytic McNemar’s test confirmed a significant reduction in misclassifications across the development folds. On the strictly held-out test set, the framework’s superiority was confirmed by a statistically significant reduction in classification errors (exact McNemar p < 0.001), alongside strong gains in imbalance-robust metrics such as BAcc (0.618, +12.8%) and the MCC (0.288, +38.5%), achieving an F1-score of 0.719. Overall, the findings of the complexity-aware framework indicate that explicitly representing the market’s informational state and transitions yields more stable, well-calibrated, and operationally reliable forecasts in regime-shifting financial environments, supporting enhanced robustness and practical deployability. Full article

Healthcare workforce planning continues to face entrenched challenges arising from the complex adaptive nature of health systems and the ongoing misalignment between workforce capabilities and system purpose. This paper introduces a conceptual meta-system framework grounded in systems and complexity thinking, positioning patient-centred care as the core system purpose and the guiding principle for workforce design. Drawing on the vortex model to visualise the nested layers of a health system—from individual care to national policy—the framework integrates interdependent domains, including system-level workforce needs. By synthesising global examples and varied planning strategies, the paper critiques the limitations of traditional linear forecasting and advocates for whole-system, needs-based approaches that embed dynamic feedback and stakeholder collaboration. It underscores the importance of strong partnerships between education and practice and highlights the role of adaptive leadership in aligning workforce planning with organisational purpose. Rather than offering prescriptive solutions, the framework serves as a catalyst for critical reflection, encouraging policymakers and healthcare leaders to tailor workforce strategies to their specific contexts. Ultimately, this conceptual approach seeks to enhance system resilience, improve health outcomes, and reduce future care demands through genuine alignment between workforce planning and the evolving needs of patients and health systems. Full article