Search Results (83,948)

In the underground mine ventilation area, the absence of robust solutions for nonlinear programming models has impeded progress for decades. To overcome the enduring difficulty of solving nonlinear optimization models for mine ventilation optimization, a major technical bottleneck, we first develop an advanced linear optimization technique. This method transforms the nonlinear ventilation optimization and regulation model into a linear control model, avoiding the limitation of difficulty in solving the nonlinear mathematical model. The linear strategy opens up a new solution idea for the nonlinear calculation of the mine ventilation optimization and regulation. Furthermore, this study introduces evaluation metrics for ventilation scheme quality, including minimal energy consumption, fewest adjustment points, and optimal placement of these points, enhancing flexibility in ventilation network optimization. By analyzing the ventilation model control objectives and constraints, we formulated a linear optimization model and developed a multi-objective mixed-integer programming model for ventilation network optimization. This paper constructs and verifies a calculation example model for mine ventilation optimization, assessing its reliability based on airflow distribution calculations. Full article

Climate change has intensified extreme weather events worldwide, such as droughts, which have severely affected South Africa’s rangelands by reducing productivity and increasing livestock mortality. This study aimed to investigate variability in grazing capacities and stocking rates with respect to land tenure, long-term grazing capacity norms, field surveys, and farmer perceptions during and post-drought conditions in the three biomes in South Africa. In-person interviews and field surveys were conducted with 85 farmers from the Grassland (n = 25), Savanna (n = 35), and Nama-Karoo (n = 30) biomes and vegetation condition was surveyed during or after the drought. Grazing capacity did not differ significantly across land tenure systems in the Savanna biomes (p > 0.05), but significant differences were found in the Grassland and Nama-Karoo biomes (p< 0.05). Over > 60% of farmers in the Nama-Karoo biome rated their rangeland condition as poor because of the drought, and field surveys showed that grazing capacities were four times lower than the national recommended grazing capacity norm. Considering the high inter-annual variability in vegetation productivity and differences in farmers’ perceptions based on local knowledge, it is recommended that the Department of Agriculture adopt flexible grazing capacity ranges in the regulations of the Conservation of Agricultural Resource Act 43 of 1983. Full article

The rate pressure product (RPP) is a non-invasive index of myocardial oxygen consumption, derived from heart rate (HR) and systolic blood pressure (SBP). While aerobic exercise is known to improve cardiovascular efficiency, evidence is limited for racialized populations, particularly African Canadians and South Asians who face elevated cardiovascular risk. Objective: The objective of the study was to examine whether a 10-session dance aerobics program provides a cardiovascular stimulus sufficient to affect RPP and blood pressure responses in these groups. Methods: A total of 160 participants with hypertension or related conditions (80 African Canadians, 80 South Asians) completed 10 sessions of community-based aerobic dance. Pre- and post-intervention measurements of systolic blood pressure (SBP), diastolic blood pressure (DBP), HR, and RPP were obtained and analyzed using non-parametric statistical tests. Results: Both groups showed reductions in blood pressure after the intervention. South Asians demonstrated moderate decreases in SBP and RPP, while African Canadians exhibited stable or slightly increased RPP values despite improvements in SBP and DBP. Between-group comparisons showed significant differences in SBP and HR (p < 0.05), but changes in RPP did not reach statistical significance (p > 0.05). Despite the modest reductions in systolic BP (≥5 mmHg), this may carry clinical significance. Conclusion: This study highlights that blood pressure and RPP responses to exercise may differ across ethnic groups. Short-term dance aerobics effectively reduced blood pressure in both African Canadian and South Asian participants, supporting its role as a culturally adaptable intervention. These findings underline the importance of tailoring exercise recommendations to ethnic and cultural contexts and provide a case for larger studies in a multi-ethnic population. Full article

Restoration plantations in subtropical regions, often established with fast-growing tree species such as Acacia auriculiformis A. Cunn. ex Benth and Eucalyptus urophylla S. T. Blake, are frequently developed on highly weathered soils characterized by phosphorus deficiency. To investigate strategies for mitigating nutrient imbalances in such ecosystems, a long-term (≥13 years) fertilization experiment was designed. The experiment involved three fertilization regimes: nitrogen fertilizer alone (N), phosphorus fertilizer alone (P), and a combination of nitrogen and phosphorus (NP) fertilizers. The objective of this study was to investigate the effects of long-term fertilization practices on soil quality in subtropical plantations using a soil quality index (SQI). Consequently, all conventional soil physical, chemical, and biological indicators associated with the SQI responses to long-term fertilization treatments were systematically evaluated, and a principal component analysis (PCA) was conducted, along with a literature review, to develop a minimum dataset (MDS) for calculating the SQI. Three physical indicators (silt, clay, and soil water content), three chemical indicators (soil organic carbon, inorganic nitrogen, and total phosphorus), and two biological indicators (microbial biomass carbon and phosphodiesterase enzyme activity) were finally chosen for the MDS from a total dataset (TDS) of eighteen soil indicators. This study shows that the MDS provided a strong representation of the TDS data (R² = 0.81), and the SQI was positively correlated with litter mass (R² = 0.37). An analysis of individual soil indicators in the MDS revealed that phosphorus addition through fertilization (P and NP treatments) significantly enhanced the soil phosphorus pool (64–101%) in the subtropical plantation ecosystem. Long-term fertilization did not significantly change the soil quality, as measured using the SQI, in either the Acacia auriculiformis (p = 0.25) or Eucalyptus urophylla (p = 0.45) plantation, and no significant differences were observed between the two plantation types. These findings suggest that the MDS can serve as a quantitative and effective tool for long-term soil quality monitoring during the process of forest sustainable management. Full article

As the terminal reservoir of the South-to-North Water Diversion’s Eastern Route, Dongping Lake is critical for safeguarding the northern water supply. Analysis of 33 water–sediment sites revealed the following. (1) Waterborne heavy metals (HMs) below WHO limits, confirming the good water quality. (2) Sediment HM enrichment exceeding background levels, with Cd posing high ecological risk (mean E_r = 135), and moderate overall pollution. (3) Speciation showed V, Cr, Co, Ni, Cu, Zn, and Pb predominantly in residual fractions, while Cd exhibited high bioavailability and Pb was in reducible state. Ecological risk assessment indicated that V and Cr tend not to cause environmental pollution; Co, Ni, Cu, Zn, and Pb only cause slight pollution; and Cd causes serious point-source pollution. The carcinogenic risk of surface sediments to children is not negligible. (4) Source apportionment identified industrial emissions as the primary HM contributors, with Cd deriving from agricultural runoff (phosphate fertilizers) and industrial discharges. This study offers valuable baseline information for water quality management in mega-water-transfer projects, directly supporting the Jiaodong Main Line and Yellow River Crossing operations. Full article

The Atlas cedar Cedrus atlantica is a relict and endemic conifer from Morocco and Algeria, although plantations may be found in several locations aside from its natural range. Recurrent droughts have been widely related to Atlas cedar dieback, growth decline, and mortality, but the genetic basis of potential adaptive capacity is unknown. We used the double digest restriction-site associated DNA sequencing technique (ddRAD-seq) to describe the genetic structure and variability of Atlas cedar along an aridity gradient in Morocco. Furthermore, we investigated the potential genetic origin of three Spanish plantations, also along an aridity gradient. The obtained single nucleotide polymorphisms (SNPs) were used to perform genotype–environment associations (GEAs) to define SNPs related to bioclimatic variables of temperature and precipitation. The vulnerability of this species to environmental variations was also estimated by its risk of non-adaptedness (RONA). Population structure showed a divergence between the Moroccan natural stands and some of the Spanish plantations, with each Moroccan nucleus being genetically distinct. The genetic variability was significantly lower in plantations than in natural populations. The drier Spanish plantations (easternmost) were genetically very similar to the driest Moroccan population (southernmost), suggesting that as its origin. A total of 41 loci under selection were obtained with the Moroccan dataset. In relation to temperature and precipitation variables, isothermality showed the highest number of associated loci (10) in GEA studies, and genotype–phenotype associations (GPAs) showed one locus associated with the Specific Leaf Area. RONA value was higher in the southernmost High Atlas population, where rising temperature was the main driver of expected genetic offset by allele frequency changes under the worst emissions scenario. In contrast, Spanish plantations would need smaller genetic changes to cope with the expected climate change. Likely gene flow from southern to northern areas suggests a latitudinal heading, where Spanish plantations might operate as an assisted migration. Moreover, one locus showed a northern/southern pattern in saplings but not in adults, suggesting a potential latitudinal pattern of selection. Our results are discussed on the basis of their management and conservation. Full article

Ensuring the long-term electro-mechanical reliability of high-voltage alternating current (HVAC) insulator strings requires a detailed understanding of how multiple environmental and electrical stressors influence the corrosion behavior of hot-dip galvanized steel fittings. In this study, a three-factor, three-level L9(3³) orthogonal accelerated corrosion test was conducted to systematically evaluate the individual and interactive effects of marine salt deposition (0–10 g m⁻² day⁻¹), acetic acid pollution (0–8 µg m⁻³), and 50 Hz AC leakage current (0–10 mA) on miniature pin-type assemblies. A comprehensive post-corrosion characterization approach was employed. The results revealed that chloride loading from salt deposition was the dominant contributor to corrosion. However, the synergistic interaction between salt and leakage current led to an acceleration in zinc depletion compared to the additive effect of the individual factors. A quadratic regression model with a high correlation coefficient was developed to predict corrosion volume per unit area. The findings offer a mechanistic explanation for field-reported failures in coastal power grids and provide actionable guidance for optimizing corrosion-resistant coatings and implementing electrical mitigation strategies. Full article

Background: Dental caries arise from polymicrobial biofilms and require interventions that address both local virulence and systemic burden. Methods: A curated set of 124 neem-derived phytochemicals was screened against Streptococcus mutans glucansucrase (3AIC) and Staphylococcus aureus DNA gyrase B (3U2D) using harmonized AutoDock Vina parameters. Ligand standardization and receptor preparation followed conventional protocols. Results: The most favorable docking scores reached −10.7 kcal·mol⁻¹ for 3AIC and −8.9 kcal·mol⁻¹ for 3U2D. Redocking produced pose RMSD values of 1.52 Å (3AIC) and 0.96 Å (3U2D). Per-receptor ADMET profiles for the six top-ranked compounds indicated median logP values of 4.93 (3AIC) and 4.52 (3U2D), median TPSA values of 80.3 and 62.9 Ų, median rotatable bonds of 2.5 and 1.0, and median QED values of 0.41 and 0.76, respectively. Conclusions: An integrated, dual-target screen prioritized neem constituents with plausible local anti-cariogenic activity and physicochemical features compatible with systemic disposition. These in silico findings motivate targeted experimental validation. Full article

Natural playgrounds have garnered growing attention as supportive environments for children’s mental health. This study develops an analytical framework grounded in affordance theory and incorporates the Pleasure–Arousal–Dominance (PAD) model to examine the relationships between physical environmental features—and their combinations—in natural playgrounds and children’s emotional perceptions. Using the Yunhu Natural Playground in Fuzhou, China, as a case study, we selected seven typical behavior setting units. Environmental features were assessed through UAV imagery and on-site observations, while PAD-based visual questionnaires were employed to collect emotional responses from 159 children. By applying correlation analysis, random forest, and regression tree models, this study identified key environmental predictors of children’s emotional responses and revealed heterogeneous mechanisms across the three emotional dimensions. The results indicated that seasonal flowering/fruiting plants, accessible lawns, and structured play facilities were critical in supporting children’s pleasure, arousal, and dominance. Specifically, pleasure was primarily associated with sensory enjoyment and contextual aesthetics, arousal favored open grassy areas, and dominance was linked to environments with clear structure and manipulability. Based on these findings, this study proposes a spatial configuration strategy characterized by “nature as foundation, play encouraged, and structure clarified” to promote the positive development of children’s multidimensional emotional experiences. This research contributes empirical evidence on the role of physical environmental features in supporting children’s play behaviors and expands the theoretical understanding of the “emotional effects” of green spaces. While the findings are exploratory and context-specific, they emphasize the critical role of the sensory–behavioral–emotional chain in shaping children’s well-being and provide theoretical and practical guidance for the design of emotionally supportive, child-friendly, natural play environments in schools, parks, and residential areas. Full article

Optimizing resources to produce higher quality food is key to promoting more resilient agroecosystems. Although the use of biostimulants in agriculture has been gaining importance in recent years, their success depends on edaphoclimatic conditions and on the specific plant species. For this reason, the main aim of this study was to evaluate the effect of biostimulants (amino acids obtained from the enzymatic hydrolysis of plant extracts) on durum wheat yield variables and grain quality (protein content). Five treatments (control treatment—T1, biostimulants—T2, slow-release urea—T3, biostimulants plus slow-release urea—T4, Mg and micronutrients—T5) were tested in a field experiment conducted over 3 seasons in the south of Spain; all were dosed at 120 kg N ha⁻¹. The number of spikes increased significantly with biostimulant treatments in the first season (up to 33%, T2 and T4), while the highest significant grain yields were obtained with biostimulants applied individually in the first season (29.5%-T2) and biostimulants in combination with slow-release urea the second season (27.3%-T4), related to T1. Grain protein concentration was influenced by the treatment only in the second season, the driest during the study, when it was increased with biostimulants up to 4.2% with T2 in comparison with T1. Total protein production increased (28.1%T2) in the first season, (8.1–21.9% for T2–T4) in the second season and (6,5% T4) in the third season, when biostimulants were applied alone or in combination with slow-release urea, respectively. In general, plants treated with Mg and micronutrients produced a lower number of spikes, less yield, and reduced total protein compared to those doses with biostimulants. The application of amino acids as biostimulants was demonstrated to enhance durum wheat yield and total protein production and could be a potential tool for promoting nitrogen use efficiency in semi-arid areas. Full article

Background/Objectives: The maxillary labial frenum (MLF) is a connective tissue structure attaching the upper lip to the maxillary alveolar process. Its morphology varies significantly among individuals and is often most prominent during early childhood. While hypertrophic or low-attaching frena have been associated with diastemas, feeding issues, and speech impairments, there is no causal evidence supporting early surgical intervention. This review aims to examine current evidence regarding the timing and necessity of frenectomy procedures and to evaluate the implications of early versus delayed intervention. Methods: A narrative review was conducted using twenty peer-reviewed articles published in the past 10 years, with one additional article from 2012 included for its ongoing relevance. Databases searched included PubMed, the NIH database, the Reference Manual of Pediatric Dentistry, and journals from the American Academy of Pediatrics. Inclusion criteria were English-language, peer-reviewed studies that addressed the morphology, classification, diagnosis, management, and outcomes of MLFs across age groups. Excluded were studies focusing solely on mandibular, buccal, or lingual frena; non-English publications; case reports; and articles lacking full-text availability. Results: The literature suggests that premature frenectomy, prior to the eruption of permanent maxillary canines, typically between 9 and 12 years of age, is associated with frenum regrowth, surgical complications, and orthodontic relapse. Additionally, a lack of standardized diagnostic criteria contributes to inconsistent clinical decision-making. Conservative management, including monitoring, is strongly recommended as the frenum often migrates apically as the maxilla develops. Factors such as airway obstruction and developmental delays should be ruled out before considering surgery. Conclusions: There is insufficient evidence to support early surgical intervention for MLF-related concerns. A conservative, individualized approach, delaying frenectomy until after permanent canine eruption, may minimize complications, improve long-term outcomes, and allow the frenum to migrate apically as the patient develops. Standardized diagnostic tools are urgently needed to guide clinical decision-making. Full article

As apex predators, felids (Felidae) face unresolved phylogenetic controversies due to their recent rapid speciation and remarkable morphological conservatism. Previous studies, often relying on a limited number of genetic markers, were constrained by insufficient data and conflicting phylogenetic signals, leaving these disputes unresolved. Therefore, establishing a robust phylogenetic framework based on larger-scale genomic data is crucial. This study integrated complete mitogenomes from 37 species representing all major felid genera to characterize genomic diversity, selection pressures, and phylogenetic relationships. Results revealed conserved gene content and arrangement patterns but significant intergenic variation in nucleotide composition, with the light-strand encoded ND6 exhibiting pronounced strand-specific bias. Nucleotide diversity was highest in ND4L (Pi = 0.132) and ATP6 (Pi = 0.131), suggesting their utility as novel markers for species delimitation and population studies. Selection pressure analysis indicated strong purifying selection on cytochrome oxidase subunits (e.g., COX1 Ka/Ks = 0.00327) but relaxed constraints on ATP8 (Ka/Ks = 0.12304). Phylogenies reconstructed from the complete 13PCGs + 2rRNAs dataset (showing high congruence between maximum likelihood and Bayesian methods) clearly delineated Felidae into two primary clades (Pantherinae and Felinae), confirming monophyly of all genera and positioning Neofelis nebulosa as the basal lineage within Pantherinae. Crucially, exclusion of ND6 (12PCGs + 2rRNAs) yielded topologies congruent with the complete 13PCGs + 2rRNAs dataset, whereas single-gene or limited multi-gene datasets produced inconsistent trees (particularly at genus-level nodes). This demonstrates that near-complete mitogenomic data (≥12PCGs + 2rRNAs) are essential for reconstructing robust felid phylogenetic frameworks. Our study provides insights into carnivoran mitogenome evolution. Full article

Guinea pigs (Cavia porcellus) are bred as livestock in South American countries from the Andean region, including Ecuador. Despite their importance for the local rural economy, no public health management guidelines have ever been implemented for guinea pig farming. Moreover, several reports have shown the carriage of diverse zoonotic pathogens in livestock guinea pigs, including respiratory and enteric pathogens, or Toxoplasma gondii. Leptospirosis, a zoonotic disease caused by bacteria from Leptospira genus, is endemic in Ecuador and has multiple animal reservoirs, with rodents considered to be the main vector for transmission to humans. However, the role of livestock guinea pigs in the epidemiology of leptospirosis is poorly understood. In this study, the prevalence of antibodies against Leptospira in guinea pigs from Ecuador was analyzed with the Microaglutiantion Test (MAT). Moreover, the shedding of Leptospira by backyard livestock guinea pigs was also addressed, analyzing fecal and urine samples by qPCR for lipL32, secY and rrs genes. From the 118 guinea pigs analyzed by MAT, 61.9% were positive for 19 different pathogenic serovars, with Icterohaemorrhagiae, Pomona, Castellonis and Bataviae being the most prevalent ones. From the 231 urine samples and 225 fecal samples collected, 27.7% and 78.7% were positive for Leptospira by qPCR, respectively. Our results highlight the role of livestock guinea pigs as a reservoir for leptospirosis. Moreover, this study underscores the zoonotic threat associated with the shedding of Leptospira within households in rural communities where guinea pigs are bred as livestock. Animal and public health guidelines from a One Health perspective must be implemented to prevent leptospirosis transmission from guinea pigs in Ecuador and other countries in the Andean Region where the breeding of backyard livestock guinea pigs is common. Full article

Zelkova schneideriana (Ulmaceae), an endemic relict species of the Tertiary in China, has experienced a sharp decline in population due to habitat fragmentation, poor natural regeneration, and anthropogenic disturbances. It is currently listed as a category II national key protected wild plant and categorized as Vulnerable by the International Union for Conservation of Nature (IUCN). To explore its response mechanisms to climate change, this study integrates 11 species distribution models (SDMs) to comprehensively predict its suitable habitat distribution patterns. Key environmental variables were identified as Bio06 (minimum temperature of the coldest month, 21.57%), Bio02 (mean diurnal range, 19.81%), Bio17 (precipitation of the driest quarter, 13.52%), Bio15 (precipitation seasonality, 8.32%), Bio07 (temperature annual range, 8.15%), Bio12 (annual precipitation, 6.58%), and elevation (6.57%), collectively contributing approximately 85%. Spatiotemporal analysis revealed that during historical glacial periods, suitable habitats were significantly restricted, and highly suitable zones were absent under extreme climatic conditions, suggesting the presence of potential glacial refugia. Under current climatic conditions, highly suitable habitats have expanded notably. However, under the high-emission scenario (SSP585) in the future, the suitable range is projected to shrink considerably, with a drastic reduction in highly suitable areas. Moreover, the suitability centroid is expected to shift markedly toward higher elevations in the northeast, indicating a potential adaptation strategy of Z. schneideriana toward mountainous regions in Hunan, Hubei, and Chongqing. These findings provide quantitative guidance for the formulation of targeted conservation strategies for Z. schneideriana and offer methodological insights for predicting suitable habitats and managing related relict plant species under the threat of climate change. Full article

The green landscapes of oasis cities play an important role in maintaining ecological security. However, these ecosystems face increasing threats from desertification and fragmentation, driven by intensifying climate change and rapid urbanization. Understanding the characteristics and driving mechanisms behind changes in green landscape patterns is crucial for advancing sustainable urban green space management. This study explores the spatio-temporal changes in the green landscape pattern in Urumqi during 1990–2020 using a random forest classifier. This study also applies geographical detectors and geographically weighted regression to comprehensively determine the driving mechanism and spatio-temporal nonstationarity. The results are as follows: (1) The landscape types are primarily dominated by unused land, urban green spaces, and construction land, accounting for more than 80%. The areas of urban green spaces, water bodies, cropland, and unused land decreased by 0.38%, 37.41%, 0.57%, and 4.58%, respectively, from 1990 to 2020. With rapid urbanization, construction land exhibited a significant expansion trend, and the degree of fragmentation of urban green spaces increased spatially over these 30 years. (2) From 1990 to 2020, each landscape index exhibited fluctuating characteristics. Overall, the Shannon’s diversity and evenness indices of the urban green landscapes exhibited an increasing trend. The contagion and connectivity indices exhibited a decreasing trend, decreasing from 50.894 and 99.311 in 1990 to 46.584 and 99.048 in 2020, respectively. (3) During these 30 years, the dynamics of urban greenery were affected by a combination of natural and social factors, with elevation determining the overall urban green distribution pattern. Precipitation and temperature dominate the urban green space changes in the north and south of Urumqi. Socioeconomic factors such as GDP, population, river distance, and town distance regulate the urban green space changes in the central built-up area. Full article