Search Results (1,792)

The genus Sigara Fabricius, 1775 (Hemiptera: Corixidae) is an important freshwater bioindicator, but its conservative morphology complicates traditional species identification. This study combines DNA barcoding, traditional taxonomy, and climatic factors within an integrative framework to provide new insights into species delimitation. We analyzed cytochrome c oxidase subunit I (COI) sequences from 501 Sigara specimens collected from 15 countries, including 95 newly generated COI barcodes. Our integrated approach included phylogenetic analyses, genetic distance assessments, and ecological niche modeling. The results revealed remarkable diversity, with sequences clustering into 46 Barcode Index Numbers (BINs). COI genetic distances showed a pronounced bimodal pattern, with most intraspecific divergences below 1% and interspecific divergences mainly ranging from 8–16%, while the few intermediate divergences (4–8%) suggested potential cryptic diversity or recent species divergence. Most morphologically defined species corresponded to distinct molecular lineages, supporting traditional taxonomy, whereas some morphospecies exhibited genetic discordance potentially associated with species divergence. Integrative analyses revealed that climatic factors, particularly isothermality and seasonal temperature and precipitation, are major drivers of Sigara MOTU distributions, highlighting the important role of climate in shaping their geographic patterns. These findings indicate that although COI barcodes are not sufficient to define the species boundaries of Sigara alone, they provide a key entry point for the accurate division of species, which in turn promotes the development of molecular tools for freshwater ecological monitoring and conservation. Full article

The heterothallic fungus Bipolaris maydis, the causal organism of southern corn leaf blight, is a destructive pathogen of corn and is considered to predominantly reproduce asexually, as no perfect reproductive stage has been discovered under natural conditions. In this study, a multiplex PCR with mating type-specific primers was used to investigate the temporal change and spatial distribution of mating types in several B. maydis populations in China. Mating type monitoring demonstrated that both mating types co-existed throughout the entire monitoring period across the seven monitoring locations, with mating type frequencies skewing significantly (p < 0.05) to MAT1-2 during the period of 2015 to 2020 and being practically symmetric after 2020, implying that the two populations were approaching equilibrium. Both mating type isolates were detected within the same leaf or field, affording a high theoretical likelihood for the two mating type isolates to cross sexually. In addition, both MAT1-1 and MAT1-2 isolates were detected from large-scale geographical regions in China, with mating type frequencies approaching a null hypothesis ratio of 1:1 in most populations, suggesting frequency-dependent selection consistent with sexual reproduction. Conclusively, our results provided indirect evidence supporting the potential for sexual reproduction in B. maydis under natural conditions, although no sexual morphs have yet been discovered in the field. Full article

The growing volume of tourism in European mountain national parks has resulted in numerous conflicts between nature conservation and the expectations of various stakeholder groups. Exceeding ecological and social carrying capacities has led to an ongoing debate on implementing visitor limits and further restrictions, the effectiveness of which strongly depends on public understanding and acceptance. Therefore, the main aim of this study was to assess the level of knowledge regarding the general system of nature conservation, attitudes toward potential regulations, and their impact on conservation and tourism development across three stakeholder groups. A non-probability, purposive-convenience sampling strategy was utilized due to the specific characteristics of the surveyed stakeholder groups. The research was conducted using an online questionnaire distributed to tourists, mountain guides, and employees of the Babia Góra, Gorce, Pieniny, and Tatra National Parks, resulting in a total sample of 106 respondents. Statistical differences among the national parks employees (n = 24), mountain guides (n = 42) and tourists (n = 40) were analyzed using the Fisher–Freeman–Halton exact test due to violated Chi-square assumptions, supplemented by Cramér’s V for effect size. The study demonstrated that national park employees and mountain guides possessed significantly higher factual knowledge regarding biodiversity threats and zoning regulations compared to tourists. Significant differences among stakeholder groups were confirmed across multiple dimensions (p = 0.005 to 0.05), with Cramér’s V values indicating moderate relationships (V = 0.21 to 0.26). Conversely, national park employees and tourists expressed stronger support for expanding protected areas, whereas mountain guides more frequently associated new national parks with tourism restrictions. Moreover, the majority of respondents across all stakeholder groups agreed that: (i) nature protection is the main goal of national park establishment; (ii) educational activities are the most effective methods of protecting nature from tourism-related threats; (iii) leaving trails should be banned in all national parks, and (iv) seasonal limits on tourist entry should be obligatory in the most frequently visited parks. The lack of significant differences was confirmed by statistical test (p = 0.08–0.93). Considering the findings of this preliminary investigation, it is suggested that future research directions should include additional stakeholder groups and encompass a wider geographical area. Full article

Background: Tinea capitis remains one of the most common superficial fungal infections in children worldwide and represents an important public health concern due to its high prevalence, potential complications, and changing epidemiology. This study aimed to characterize the epidemiological trends and etiological distribution of tinea capitis across the Americas through a systematic review of the available literature. Methods: A systematic search was conducted in MEDLINE (PubMed), Scopus, SCILIT, and SciELO following PRISMA guidelines. A total of 250 records were identified, of which 75 duplicates were removed. After title and abstract screening and eligibility assessment, 90 studies were included. Observational studies, prevalence studies, case series, and case reports reporting epidemiological or etiological data on tinea capitis in countries of the American continent were considered eligible. Methodological quality was assessed using the Joanna Briggs Institute (JBI) critical appraisal tools. No formal certainty-of-evidence assessment or meta-analysis was performed due to the descriptive nature and heterogeneity of the included studies. This review was not prospectively registered. Results: The 90 included studies comprised 506,086 reported cases of tinea capitis. Marked regional differences were identified in the distribution of dermatophyte species. Trichophyton tonsurans predominated in North America and several Caribbean countries, whereas Microsporum canis was the most frequently reported etiological agent in much of South America and parts of Central America, suggesting an important role of zoonotic transmission in these regions. Variations in prevalence and species distribution were also associated with geographic, socioeconomic, and demographic factors. Overall, the included studies demonstrated low-to-moderate methodological risk of bias. Conclusions: These findings demonstrate substantial heterogeneity in the epidemiology of tinea capitis throughout the Americas and highlight the importance of continuous surveillance, accurate mycological diagnosis, and region-specific public health strategies to improve disease control and guide appropriate therapeutic interventions. Full article

Background: Fenugreek is a widely used aromatic herb valued as a food ingredient. Fenugreek seeds and leaves are rich in antioxidants and bioactive compounds that support overall health, particularly gastrointestinal function. The present paper describes a green synthesis of silver nanoparticles (AgNPs) utilizing aqueous and ethanolic extracts of fenugreek seeds (Trigonella foenum-graecum L.) grown in Bulgaria, Egypt, and India in order to find differences in AgNPs formation depending on geographic region and solvent used for the extraction and to find any changes in their spasmolytic activity. Methods: FT-IR, High-Resolution Transmission Electron Microscopy (HRTEM), DLS, and zeta-potential were used to characterize the produced AgNPs, aiming to verify their stability, size distribution, and formation. The biological activities of these extracts are then compared. Results: The ethanolic extracts were more effective for producing smaller, more homogeneous, and relatively stable AgNPs compared to aqueous extracts. Differences in phytochemical composition, which have a direct impact on the nucleation, development, and stability processes of NPs, could be the reason for the observed variances between plant extracts. AgNPs (aqueous), originated from Bulgaria, exhibited the strongest spasmogenic activity under the applied experimental conditions. The biosynthesized AgNPs also showed a selective antifungal activity against Aspergillus and Penicillium spp., with modest antibacterial effects. Conclusions: From a biological perspective, all samples’ fenugreek extracts had a minimal impact on gastrointestinal contractility, but the AgNPs derived from these extracts had a greater spasmogenic effect. These findings point to a combination that enhances both functional efficacy and bioavailability. The Bulgarian fenugreek aqueous extract produced AgNPs with the strongest spasmogenic activity of all the preparations examined. The results showed the potential of AgNPs from fenugreek seeds for biomedical applications. Full article

Pelargonium graveolens L’Hér. is a widely distributed aromatic plant that has been utilized in traditional medicine for an extended period. It is currently experiencing a surge in popularity in modern phytotherapy. The ethnopharmacological uses of this species include treatment of respiratory tract infections, digestive disorders, and analgesia. The plant’s multifaceted biological activity is attributed to the presence of monoterpenes, such as citronellol and geraniol, as well as non-volatile polyphenolic fractions and organic acids. Research has demonstrated the efficacy of PGEO (P. graveolens essential oil) in mitigating inflammation, a phenomenon attributable to the suppression of NF-κB and MAPK signaling pathways, as well as the inhibition of inflammatory mediators such as histamine, prostaglandins (PGs), and nitric oxide (NO). Furthermore, a broad spectrum of antimicrobial activity has been demonstrated against pathogens such as MRSA and Mycobacterium tuberculosis, whilst myricetin derivatives have been shown to enable the effective eradication of bacterial biofilms. It is also noteworthy that the oil’s components can reduce ACE2 receptor expression, indicating their potential to inhibit SARS-CoV-2 infection. Active compounds, such as geraniol, have been shown to modulate metabolic processes through interaction with LXR and FXR nuclear receptors. In addition, these compounds have been observed to exhibit spasmolytic effects within the gastrointestinal tract by blocking calcium channels. The influence on the HPA axis and the GABAergic system provides a scientific rationale for the plant’s traditional use in reducing stress and anxiety. Nevertheless, variations in chemical composition, determined by geographical origin, and an insufficient number of rigorous clinical data hinder the full medical implementation of this plant. It is imperative that further standardization of extracts and their verification in clinical trials is undertaken. Full article

Background/Objectives: Severe dengue and dengue–malaria coinfection represent major diagnostic and therapeutic challenges in tropical endemic settings, where overlapping clinical manifestations may delay recognition of deterioration. This study aimed to describe the clinical and epidemiological characteristics of patients with severe dengue, dengue with warning signs, and dengue–malaria coinfection treated at a referral hospital in Montería, Córdoba, Colombia. Methods: A retrospective case series was conducted by reviewing medical records of patients diagnosed with dengue between 2018 and 2023. Cases classified as dengue without warning signs were excluded. The final analysis included patients with dengue-warning signs, severe dengue, and dengue–malaria coinfection. Dengue classification followed the 2009 World Health Organization criteria, and malaria was confirmed by thick blood smear. Sociodemographic, clinical, laboratory, geographic, and outcome-related variables were collected. Descriptive analyses were performed, and selected categorical variables were compared using Fisher’s exact test. Results: Fifty-three patients were included: 25 (47.17%) with severe dengue, 14 (26.42%) with dengue with warning signs, and 14 (26.42%) with dengue–malaria coinfection. Severe dengue was more frequent among females, whereas dengue with warning signs and coinfection predominated in males. Children accounted for the highest proportion of severe dengue cases, while coinfected cases were mainly distributed between childhood and adolescence. Fever was documented in all patients. Edema, elevated hematocrit, severe plasma leakage, and hemodynamic compromise were more frequent among severe dengue cases, whereas myalgia differed significantly across clinical groups. Ten deaths were recorded, six occurring in coinfected patients. Conclusions: Severe dengue and dengue–malaria coinfection are clinically complex conditions with overlapping manifestations and potentially fatal outcomes, highlighting the need for early recognition, differential diagnosis, and close monitoring. Full article

Urban–rural governance and planning systems, as viewed through the lens of online public attention, are reshaping approaches to achieving coordinated development of cultural heritage conservation and urban space. Taking Nanchang as a case study, this paper investigates the application mechanism of online public attention in the evaluation of heritage corridor nodes and the formulation of optimization strategies. Employing multi-source data collection, we extracted textual content from online travelogues. We quantified the online attention level of each cultural heritage unit and analyzed its spatial distribution using kernel density estimation and standard deviational ellipse methods. We then applied a minimum resistance model, incorporating geographic data on land use and transportation networks, to identify potential heritage corridor routes. Based on attention classification, we propose a three-tier optimization strategy: core-leading, marginal-activating, and gradient-linking. Specifically, high-attention heritage units are positioned as central nodes that reinforce corridor connectivity; low-attention nodes are targeted for activation through corridor links to overcome spatial isolation; and attention gradients serve as the basis for hierarchical integration across the network. Our results reveal a pronounced spatial pattern of “core agglomeration and peripheral dispersion” in Nanchang’s heritage corridors. High-attention resources are heavily concentrated in the historic urban core, anchoring the main corridor axes, whereas low-attention resources are scattered across peripheral counties, exhibiting a clear urban–rural attention gradient. Importantly, attention levels show a positive correlation with corridor hierarchy. These findings provide a novel perspective for heritage corridor spatial planning and offer practical insights for sustainable cultural heritage governance and culture–tourism integration in an era of pervasive internet and urban expansion. Full article

Snow disasters constitute a major natural hazard in Northwestern China, where heavy snowfall, blowing snow, and avalanches pose significant threats to infrastructure and socioeconomic activities. A scientific assessment of regional snow disaster risk is therefore critical for disaster prevention, spatial planning, and sustainable development. This study integrates multi-source remote sensing and geographic data to develop a comprehensive risk assessment method. By entropy weight method (EWM), we construct an assessment model that quantifies the combined hazard potential of heavy snowfall, blowing snow, and avalanches. The results reveal a significant spatial correlation among the three primary hazard types. The average potential hazard intensity of heavy snowfall is greater than that of blowing snow, which in turn exceeds that of avalanches. Spatially, the comprehensive snow disaster risk is most severe in the Altai Mountains, the Ili River valley, and the Tacheng region. A moderate-to-high risk level is distributed across the southwestern valleys and the foothills of the northeastern mountains. In contrast, the lowest risk areas are concentrated in certain interior valleys and the leeward slopes of the Junggar Basin. The resulting regional risk zoning was evaluated using receiver operating characteristic (ROC) curve analysis and disaster records. The model achieved an area under the receiver operating characteristic curve (AUC) of 0.871 and an overall accuracy of 84.3%, indicating good spatial discrimination between high- and low-risk zones. These metrics support the application of the framework to regional snow disaster risk assessment. Full article

Mediterranean agriculture is increasingly constrained by severe and recurrent water scarcity. Rising temperatures, declining precipitation, and more frequent droughts are driving higher crop water demand and reducing rainfall reliability. Combined with growing competition for limited freshwater resources, these climatic pressures pose a major challenge to the long-term sustainability and productivity of farming systems in the region. In this context, urban treated wastewater (UTWW) is increasingly recognized as a strategic alternative resource. Regulation (EU) 2020/741 establishes minimum quality requirements for agricultural water reuse based on the fit-for-purpose principle. The Italian regulatory framework requires regional authorities to plan water reuse by mapping reclamation facilities, water demand, and distribution networks. From this perspective, to support the planning process, this study describes the application of a Geographic Information System (GIS)-based methodology to assess the potential for UTWW reuse in Sicily by integrating national datasets (regularly updated) and comparing reclaimed water supply with irrigation demand from both qualitative and quantitative perspectives. UTWW supply was estimated by integrating data from the Italian National Institute of Statistics (ISTAT) Census of Water for Civil Use and the European Environment Agency (EEA) dataset, while irrigation demand was derived by combining Copernicus crop data, ISTAT irrigated-to-total UAA ratios and crop-specific irrigation demand (Seasonal Specific Volumes) derived from the SIGRIAN database. Two scenarios were analyzed for grasslands, vineyards, olive groves, and orchards. Scenario 1 included only wastewater treatment plants (WWTPs) located inside irrigation areas, whereas Scenario 2 also included selected WWTPs located outside irrigation areas where orographic and distance constraints allowed potentially feasible connections. Under Regulation (EU) 2020/741, potential compatibility with the required water quality classes was identified at the screening level for all crop categories considered, which require classes B, C or D. From a quantitative perspective, Scenario 1 identified 19 WWTPs serving 11 out of 38 irrigation areas with an aggregated uncapped demand coverage of 53%; only two areas reached full local demand satisfaction. Scenario 2 added 23 external WWTPs, increased potentially served areas to 20, and raised the aggregate uncapped coverage to 73%. When surplus volumes were capped within each irrigation area, effective demand satisfaction was 12% and 22% in Scenarios 1 and 2, respectively, highlighting the importance of storage, conveyance and inter-area transfer. The results indicate that treated wastewater reuse could contribute to agricultural water security and climate-resilient water management in Mediterranean regions. The framework supports the first-order identification of candidate reuse areas, but site-specific assessments of effluent quality, risk management, costs, and seasonal storage remain necessary before implementation. Full article

Lardizabala biternata is an endemic vine and the sole species of the monotypic genus Lardizabala, distributed across central–southern Chile and producing edible fruits traditionally harvested from wild populations. Despite its cultural relevance, potential agronomic value, and evolutionary singularity, its conservation status remains poorly understood because of incomplete distributional knowledge and historical nomenclatural inconsistencies. Here, we conducted a preliminary record-based spatial conservation assessment of L. biternata using a taxonomically and geographically curated occurrence database integrated with Kernel Density Estimation (KDE), Extent of Occurrence (EOO), Area of Occupancy (AOO), overlap analyses with Chile’s protected-area network (SNASPE) and the Chilean Winter Rainfall–Valdivian Forests biodiversity hotspot, and ecological representativeness assessments based on mapped vegetation-class units. Our analyses revealed substantial spatial and ecological conservation gaps. Most documented occurrence records were located outside protected areas, while KDE-derived occurrence-record density patterns were concentrated within the biodiversity hotspot, a region characterized by high endemism and intense anthropogenic pressure. Although EOO indicated a relatively broad geographic extent, AOO indicated restricted occupancy based on documented records. In addition, several mapped vegetation-class units intersecting the 95% KDE-derived occurrence-record density area lacked formal conservation coverage entirely. Together, these findings suggest that L. biternata may warrant greater conservation attention than previously recognized. This study provides the first integrated record-based spatial conservation assessment of the species and establishes a baseline framework for future conservation evaluations, ecological studies, and ex situ conservation strategies. Full article

Understanding morphological variation across geographic space is central to evolutionary and functional studies of marine vertebrates. Here, we examine variation in dorsal fin shape in the Commerson’s dolphin (Cephalorhynchus commersonii), a small coastal cetacean with a disjunct distribution across South America and the Kerguelen Islands. Dorsal fin shape was quantified using geometric morphometrics based on photographs, and comparisons were conducted across subspecies and populations. Principal Component Analysis revealed partial overlap in morphospace, with higher shape variability in the Kerguelen subspecies. Canonical Variate Analysis showed separation among geographic groups, although patterns of overlap remained. Differences in mean fin shape were observed among populations, particularly in the relative development of the free span and base of the fin. Kerguelen dolphins exhibited a relatively broader fin base and reduced free span, whereas South American populations generally showed a wider free span, with additional variation among regional populations. Morphological patterns did not fully correspond to population genetic structure, suggesting that multiple factors may contribute to phenotypic variation in this species. Similarities between geographically distant populations highlight the potential influence of shared environmental conditions. These results emphasize the value of dorsal fin morphology for investigating spatial variation in small cetaceans and provide a basis for future integrative studies combining ecological, physiological, and genetic data. Full article

The combined effects of global climate change and human activities are profoundly reshaping the geographic distribution patterns of rare and endangered plants in arid and semi-arid regions, accelerating habitat fragmentation and population decline, thereby posing a core challenge to biodiversity conservation. As a rare semi shrub endemic to the Mongolian Plateau, P. mongolica faces continuous population shrinkage due to habitat fragmentation and climate change caused by extreme weather conditions, overgrazing, and mineral extraction, leaving its survival status critically vulnerable. Based on data from 153 distribution sites, this study employed the MaxEnt model to predict the species’ optimal habitat range, analyzed key environmental factors influencing its distribution, and projected that by the 2050s and 2070s, its total suitable habitat will potentially expand northwestward with increased expansion rates as carbon emissions rise. Its distribution is mainly driven by the minimum temperature of the coldest month, the average temperature in the coldest season and precipitation in the warmest season, which conforms to the law of species movement to the northwest caused by climate warming. Full article

Agricultural subsidy policies have increasingly shifted from production-oriented support toward incentives that reward environmental stewardship and the provision of ecosystem services. Despite their rapid expansion, evidence regarding the environmental effectiveness, economic efficiency, market implications, and food-security consequences of these eco-centric agricultural subsidies remains fragmented across policy frameworks and regions. This review synthesizes current evidence on eco-centric agricultural subsidies by comparatively evaluating their environmental, economic, and policy outcomes across developed and developing economies. The review was conducted using a structured literature search following PRISMA-informed review procedures, drawing upon peer-reviewed articles, systematic reviews, policy evaluations, and international institutional reports retrieved from major scientific databases and policy sources. The evidence indicates that eco-centric subsidies generally improve biodiversity conservation, soil health, carbon sequestration, water quality, and reductions in chemical inputs when payments are appropriately targeted and supported by effective monitoring and institutional capacity. Performance-based and results-oriented payment schemes frequently demonstrate greater environmental additionality and cost-effectiveness than conventional practice-based payments; however, their broader implementation remains constrained by monitoring costs, verification requirements, administrative complexity, and regional institutional capacity. Economic outcomes are more heterogeneous, with benefits depending on program design, agroecological conditions, market structures, and farm characteristics. While these subsidies can enhance environmental returns on public investment, challenges including land-value capitalization, unequal benefit distribution, transaction costs, market distortions, and potential short-term productivity trade-offs remain important policy concerns. Evidence regarding food-security impacts is similarly context-dependent and varies across production systems and geographical regions. Overall, the review demonstrates that no single subsidy instrument is universally effective. Instead, the greatest environmental and economic benefits are achieved through integrated policy portfolios combining targeted incentives, outcome-based payments, robust monitoring systems, digital technologies, carbon-market integration, and equitable program design. The review also identifies important evidence gaps concerning developing-country experiences, long-term cost-effectiveness, and standardized evaluation frameworks, providing priorities for future research and policy development. Full article

Trichostrongylid nematodes are globally distributed gastrointestinal parasites of major veterinary and, in some cases, zoonotic importance. Accurate identification often requires an integrative approach because morphology alone may be compromised by specimen damage, cryptic diversity, and dimorphic species complexes. In the Philippines previous work has been largely limited to coproscopy, with no published DNA-based studies on adult trichostrongylids or scanning electron microscopy (SEM) documentation. Here, we provide an integrative characterization of Haemonchus contortus and Trichostrongylus axei recovered from a single goat in Mindanao, Philippines, in 2023. Identification was based on light microscopy, SEM, morphometry, and sequence data from the cox1 and ITS regions. Phylogenetic analyses and a haplotype network for H. contortus placed the Philippine material within a widely distributed lineage complex with weak geographic structuring. Because the study is based on parasites from a single host, the findings should be interpreted as a taxonomic and faunistic record rather than evidence for broader epidemiological or population-level patterns. This study provides the first molecular record of trichostrongylid nematodes from the Philippines and the first SEM-based documentation of H. contortus in the country. Broader sampling is needed to assess parasite diversity, distribution, genetic variation, and potential veterinary and public health relevance nationwide. Full article