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The maxillary canal system in Cynognathus and Diademodon is described. The hypothesis that expansion of the maxillary sinus represents a synapomorphy of the clade Cynognathia is supported. A trend towards the reduction of the inferior palpebral ramus is proposed.
A combination of measurements of the CP properties of Higgs boson interactions with electroweak gauge bosons is presented, using 140  fb^{-1} of proton-proton collisions at sqrt[s]=13  TeV recorded by the ATLAS detector. Results from vector boson fusion H→ττ/WW^{*}/γγ, inclusive H→ZZ^{*}, and WH,H→bb[over ¯] channels are combined. No evidence of CP violation is observed, and constrains on the CP-violating operators in the Standard Model effective field theory framework (SMEFT) are set in the Warsaw basis. The results from the combination improve by over 40% on previous individual limits on c_{HW[over ˜]} and, for the first time, simultaneous constraints on three coefficients c_{HW[over ˜]}, c_{HB[over ˜]}, and c_{HW[over ˜]B} are set. These limits are the most stringent constraints to date on the relevant Wilson coefficients in the SMEFT framework with minimum model dependence.
A new set of quinazolin-4-one-based chalcones was prepared from 3-(4-acetylphenyl)-2- methylquinazolin-4(3H)-one (1) via a base-catalyzed Claisen-Schmidt condensation with substituted aromatic aldehydes. Synthesis was conducted using either a conventional NaOH/EtOH protocol or a solvent-minimized mechanochemical grinding approach. The grinding method delivered chalcones 3a-j and 5 in improved yields (85-94%) within 15-25 min, compared with 65-72% over 12-20 h for the solution method. Product structures were verified by spectroscopic and elemental analyses. The anti-Alzheimer's potential was investigated through molecular docking of the complete series to propose binding modes and prioritize candidates, followed by in vitro evaluation of the five top-ranked compounds (3e, 3f, 5, 3i, and 3 h) for AChE and BuChE inhibition relative to donepezil. In vitro assays revealed the following IC₅₀ values for the compounds against AChE and BuChE: 3e (0.751 ± 0.023 µg/mL for AChE, 0.108 ± 0.003 µg/mL for BuChE), 3f (1.283 ± 0.039 µg/mL for AChE, 0.383 ± 0.01 µg/mL for BuChE), and 5 (2.148 ± 0.066 µg/mL for AChE, 1.212 ± 0.04 µg/mL for BuChE). These values suggest that 3e was the most promising dual inhibitor, outperforming donepezil in both AChE and BuChE inhibition. Docking outcomes agreed with the experimental trends, supporting this scaffold as a promising platform for dual cholinesterase inhibition. In silico ADMET assessment further indicated drug-like characteristics with predicted high oral bioavailability, supporting further lead optimization for Alzheimer's disease therapy.
In India, eight civet species have been documented. Among these, the Asian palm civet and the Small Indian civet are most frequently reported in poaching incidents for bushmeat and other purposes. In this study, we examined four processed leg samples (n = 4) seized by the Tamil Nadu Forest Department and suspected to be of civet origin. DNA was extracted and four partial mitochondrial genes (cytochrome b (cyt-b), 12 S ribosomal RNA (12 S rRNA), 16 S ribosomal RNA (16 S rRNA), and cytochrome c oxidase subunit 1 (COXI)) were amplified for species identification. Basic Local Alignment Search Tool (BLAST) analysis indicated that cyt-b provided clearer species-level resolution compared to the other genes, which showed ambiguous matches, likely due to limited reference data in the NCBI database. Phylogenetic analysis further confirmed that all samples originated from Paradoxurus jerdoni (brown palm civet). This case study shows that lesser-reported civet species may also be involved in wildlife trade and demonstrates that cyt-b is a practical genetic marker for forensic identification under current database limitations. The findings highlight the need for robust reference databases to improve species discrimination in wildlife forensic investigations and support enforcement efforts.
Environmental fungal pathogens relevant to human and animal health pose significant risks, particularly in regions with intensive farming and climate variability. Several taxa detected in Thailand's clinical and environmental samples, such as Candida tropicalis, Talaromyces marneffei, and Mucor spp., are listed in the World Health Organization (WHO) Fungal Priority Pathogen List (FPPL). This study integrated next-generation sequencing (NGS) metabarcoding and decision tree models to characterize fungal communities and identify environmental conditions associated with pathogen absence across 18 provinces of Northeast Thailand. Soil samples (n = 121) from rice, cassava, sugarcane, and rubber tree fields were collected in 2022 and analyzed for eight environmental parameters: drought level, soil water content, organic matter, nitrogen, phosphorus, potassium, soil temperature, and soil pH. Decision tree models were trained on these samples to derive absence conditions for nine WHO FPPL taxa, which were validated using an independent test dataset (n = 12) collected in 2025. Absence conditions for Falciformispora senegalensis, Mucor spp., and Talaromyces marneffei achieved perfect precision and recall in the test dataset. Precision is the proportion of samples predicted as absent that are truly absent, and recall is the proportion of truly absent samples correctly identified by the condition. Candida tropicalis, Curvularia lunata, and Lichtheimia spp. showed perfect precision but moderate recall (0.42-0.75). Conditions for Scedosporium spp. and Acremonium spp. did not generalize due to limited representation in the training data. Over three years, the fungal community became less diverse and more taxonomically consolidated, coinciding with drought intensification and nutrient shifts. Overall, combining metabarcoding with decision tree models provides a practical framework for identifying low-risk soils and supporting agricultural practices and public health surveillance.
Maintaining a physiological stoichiometric balance is a fundamental driver of foraging behaviour; yet, resource availability varies across trophic levels and vegetation strata. Therefore, primary consumers and predators may experience distinct nutritional opportunities between epigaeic and arboreal habitats. We investigated how ant communities respond to carbohydrates availability in the Brazilian Restinga - a coastal ecosystem characterized by sodium saturation and low carbohydrate availability. For that, we experimentally supplied carbohydrates (C₁₂H₂₂O₁₁, 20%), salt (NaCl, 1%) and water in both epigeic and arboreal strata to assess recruitment responses across the overall ant community as well as predominantly primary consumers and predominantly predatory ants separately. Carbohydrates were more attractive to the overall ant community, attracting eight times more species and 15 times more ant individuals than salt. This higher recruitment was consistent across feeding guilds, with primary consumers and predators exhibiting 17-fold and 42-fold increases in individual recruitment to carbohydrates as many as salt baits. Although primary consumers were recruited more in the arboreal stratum and predators in the epigeic stratum, recruitment to carbohydrate baits was consistent across vegetation strata for both the overall ant community and the feeding guilds. In conclusion, our findings show that carbohydrates in a saline coastal ecosystem strongly act as an important resource influencing ants' foraging behaviour across vegetation strata. These results highlight how stoichiometric imbalances dictate foraging decisions and community dynamics and provide insights into how resource availability influences ant-mediated ecological functions in saline environments.
Oviposition-site selection is a key maternal decision in oviparous animals, involving trade-offs among incubation conditions, offspring performance, and maternal constraints. In amphisbaenians (worm lizards), a clade of highly specialized fossorial reptiles, oviposition has long been assumed to occur obligatorily in ant and termite nests, implying strong ecological specialization. Here, we re-evaluate this assumption using new field observations and a critical synthesis of published records. We describe a natural oviposition site of the smallhead worm lizard (Leposternon microcephalum) located in a soil cavity with no evidence of ants or termites and review 18 records from nine amphisbaenian species. Across species, eggs occur not only in ant and termite nests but also in subterranean cavities and decaying logs, indicating facultative rather than exclusive use of social-insect nests. A field inspection of 31 active ant nests during the reported oviposition season yielded no eggs or amphisbaenians. Additional evidence suggests some species excavate or modify underground chambers and that at least one species oviposits communally. These findings challenge the view of strict dependence on ant and termite nests and instead support oviposition-site choice in amphisbaenians as a flexible, context-dependent maternal behavior shaped by ecological trade-offs rather than rigid specialization. Standardized surveys across microhabitats and experimental tests of incubation environments are needed to clarify how availability, costs, and benefits interact to shape nesting decisions in fossorial reptiles.
The analysis of cuticular hydrocarbon (CHC) profiles can provide valuable insights into species identification, immature development and adult ageing, sexual communication, reproductive functions, and other physiological processes of insects. This study investigated the CHC profiles across the life stages of Thanatophilus sinuatus (Fabricius, 1775), a carrion beetle species commonly associated with decomposing tissues, including human remains. We examined the first, second, and third larval instars, the pupa, and the adult male and female using gas chromatography–mass spectrometry. A total of 56 CHCs were identified, including n-alkanes, branched alkanes, and alkenes. Branched alkanes were dominant throughout development, while significant compositional differences were observed among stages. Certain compounds showed consistent proportions across development, suggesting roles in physiological or behavioral processes. Gender-specific differences were also evident, with some CHCs detected exclusively in males or females, potentially linked to sexual communication and reproductive functions. Principal component analysis revealed distinct clustering of developmental stages, and Random Forest classification with out-of-bag validation confirmed high predictive accuracy of CHC profiles for developmental stage identification. These findings highlight the potential of CHC profiling, combined with machine learning approaches, as a valuable tool, particularly useful in situations where specimens of T. sinuatus or other related species are damaged, incomplete, or present only as chemical residues, rather than when intact larvae are available. CHC profiling offers a complementary method for cases where diagnostic characters are missing or obscured.
Contact between materials occurs through microscale asperities, where stress evolves under highly localized, multiaxial deformation. Despite the significant importance to numerous scientific fields, to date, direct experimental quantification of these stress fields across the materials in contact has remained elusive. Here, we combine in situ scanning synchrotron X-ray nanodiffraction with 80 nm spatial resolution and a custom indentation setup to resolve nanoscale stress fields developing at the contact between a diamond indenter and both single-layer ZrN and multilayered ZrN-ZrCu thin films. We introduce a nanomechanical probe comprising a single-crystalline diamond wedge coated with nanocrystalline diamond to simultaneously probe stress accumulation within the indenter. X-ray scattering and scanning electron microscopy, micromechanical testing, analytical and elastic-plastic finite element modeling corroborate the nanoscale stress maps obtained for both sides of the tip-surface contact region. The individual interfaces along the projected load paths diffuse stresses in both the tip and the multilayer, thereby controlling the overall mechanical response at the asperity. Consequently, the stored elastic energy is reduced by 30% in the multi-layered film in comparison with the monolithic ZrN. Finally, the measured nanoscale stress distributions elucidate the fundamental mechanisms by which artificial multi-layered materials effectively dissipate energy and prevent catastrophic failure.
A checklist of the vascular flora of the Democratic Republic of the Congo (DRC) has been assembled, based on literature, online databases, and herbarium collections. It includes 10,260 species (38 lycophytes, 347 monilophytes, 16 gymnosperms, and 9,859 angiosperms), belonging to 246 families. The five largest families are Fabaceae (11.8% of specific richness), followed by Rubiaceae (6.7%), Asteraceae (6.6%), Poaceae (6.1%), and Orchidaceae (5.6%). Strict endemics of the DRC amount to 1,099 species, i.e., 10.7%. Families represented by > 120 species and comprising a high proportion of endemics include Commelinaceae (endemism rate: 24%), Euphorbiaceae (21%), Asteraceae (16%), and Fabaceae (16%). A total of 461 introduced species are recorded outside cultivation in the country, i.e., 4.5% of the total flora. Solanaceae, Brassicaceae, and Amaranthaceae stand out with their higher-than-average proportions of introduced species. Herbs represent the most frequent life form (54%), followed by (sub)shrubs (17%), trees (14.5%), climbers (10%), and epiphytes (4%). The IUCN conservation status was retrieved for 2,633 species (25.7%), of which two species are extinct and 448 (17%) are assigned to a threat category (CR [Critically Endangered]: 36; EN [Endangered]: 184; VU [Vulnerable]: 228). IUCN status was retrieved for 184 (17%) of the endemic species, of which 135 (73%) are considered extinct or threatened.
CK2 belongs to the eukaryotic protein kinase superfamily and has a distinctive heterotetrameric quaternary structure. In the so-called CK2α2β2 holoenzyme, which is the main form of CK2 in human cells, two catalytic subunits (CK2α) are attached to a stable homodimer of non-catalytic subunits (CK2β). Most CK2 inhibitors described so far are ATP-competitive. Some of them are the subject of clinical studies because the enzyme is upregulated in many tumours, and CK2 activity contributes to tumour survival. An unconventional method to interfere with CK2 is to disturb the CK2α/CK2β interaction with small molecules. In a high-throughput screen against a 67 000-compound library using a fluorescence anisotropy-based displacement assay, we identified a group of derivatised cyclic pentapeptides that target the CK2β binding site of CK2α. The CK2β-competitive effect of these screening hits was verified using either human CK2α or its paralogous isoenzyme CK2α' as interaction partners. To this end, novel Förster resonance energy transfer-based CK2α/CK2β and CK2α'/CK2β interaction assays were developed and extensively tested. A result of these validation measurements was that the CK2β-antagonists bind more strongly to CK2α than to CK2α' although both paralogs do not differ in the amino acid composition at their CK2β interfaces. Co-crystallisation experiments of two high-affinity binders with CK2α and CK2α' led to three complex structures that confirm the binding of the compounds to the CK2β interface. The structures suggest a critical role of the β4β5-loop for the higher affinity of the compounds to CK2α compared to CK2α'. Furthermore, they offer suggestions on how to enhance their efficacy in the future.
Predation risk imposes fundamental trade-offs between survival and reproduction, often leading to sex- and age-specific differences in anti-predator behaviour. We investigated these trade-offs in the jumping spider Saitis barbipes, a species in which cryptic females and juveniles contrast with conspicuously coloured males that engage in courtship displays. Using high-quality in-focus and blurred predator images, we tested first behavioural responses and reaction distances of adult males, adult females, and juveniles. While all groups reliably recognised predator cues, adult males consistently approached stimuli more closely before showing anti-predator behaviour and frequently responded with courtship rather than defensive behaviours. In contrast, females and juveniles more often employed passive strategies such as freezing. Stimulus clarity had no effect on the type of response, whereas distance strongly influenced behavioural responses. These results indicate that predator recognition is innate, but response thresholds are context-dependent and shaped by sex, age, and reproductive role. Conspicuous adult males appear to suppress or delay anti-predator responses in favour of courtship, highlighting an evolutionary trade-off between reproductive effort and survival.
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We introduce an index based on the composition of amphibian communities that can be used to assess and monitor over time the biotic integrity of wetlands and to evaluate the priority of these sites for conservation. The Rwanda Anuran-based Biotic-Integrity Index (RABI) integrates three sub-indices, which reflect the conservation priority of species based on their distribution in Rwanda, their conservation status, and their susceptibility to habitat alteration. The functionality of the RABI was tested on 51 wetland sites distributed over the five ecozones of Rwanda. The wetland sites showed a wide range of RABI values, with marked differences between the different ecozones. The RABI reliably identified sites with a high number of threatened, range-restricted, and habitat-sensitive species and sites with high species richness. Although wetlands in agriculturally exploited areas often had high anuran-species numbers, their assemblages contained mostly widespread generalist species, resulting in lower RABI values compared to sites with lower species numbers but with threatened, specialized species. Wetlands within the four Rwandan national parks had particularly high RABI values, confirming that these areas require special protection. We identified five sites with high conservation value outside the national parks that should be considered for future protection.
Transmission of pathogens from managed to wild bees presents a significant ecological threat in diverse habitats. Interspecific pathogen transmission is widely documented and occurs frequently in shared environments. This study examines the prevalence and abundance of the bee-associated pathogens (DWV, BQCV, ABPV, CBPV, KBV, SBV, Nosema ceranae, Crithidia mellificae, Lotmaria passim, and Crithidia bombi) in wild bees sampled in sites with and without honey bees in the Coimbra district (Portugal). Using quantitative PCR and statistical modelling, the study identified interspecific pathogen transmission dynamics influenced by the presence of Apis mellifera colonies and wild bee genera. The findings revealed a high prevalence of pathogens, with DWV (87.22%), CBPV (70.71%), ABPV (48.95%) and N. ceranae (30.03%) being the most common in species. There is a broad susceptibility of different genera of bees, with a higher abundance of pathogens in Andrena, Halictus, and Megachile. The risk of ABPV and SBV infections was associated with sites close to the apiaries. Furthermore, ABPV and L. passim were mainly associated with honey bees, while C. bombi was associated with bumblebees. This study represents the first investigation of wild bee pathogens in mainland Portugal. It emphasizes the urgent need for integrative conservation strategies under a One-Health approach to mitigate the impacts of pathogens on pollinator biodiversity and ecosystem stability.
In the present study, quantitative ethnobotanical knowledge of medicinal plants utilized by the local communities for treating different human ailments in selected rural villages of Punjab, Pakistan has been documented. Semi-structured interviews and field surveys were employed to conduct field investigations from March 2024 to April 2025, with a total of 105 informants aged 18-70 years. The total number of plant species recorded and reported for the cure of 14 human ailments was 50 belonging to 25 families. Fabaceae was the dominant family with 6 species, among the documented families. The most abundant life form was herbs (26 species) and the most common part used was leaves (16 species). The highest Relative Frequency of Citation (RFC = 0.34) was found in Bombax ceiba, Cenchrus echinatus and Sonchus oleraceus. Spinacia oleracea had the highest Use Value (UV = 0.08) while the lowest UV was 0.03. Mentha canadensis recorded the highest Fidelity Level (FL = 93%) for the treatment of hyperacidity and diarrhea whereas Azadirachta indica recorded the lowest FL (69%) in the treatment of scabies and pimples. Three species recorded the highest FC (36) while three other species recorded the lowest FC (24). The results showed a high diversity of medicinal plants in the study area and significant traditional ethnobotanical knowledge. There were not enough up-to-date health care facilities in rural areas, so local residents heavily depended on the use of medicinal plants for basic health care. The study emphasized the need to maintain the knowledge of the indigenous people and conserve medicinal plants resources for sustainable use and future exploration in medicine.
Marine mammals host a variety of parasites, engaged in continuous evolutionary competition. Our understanding of parasitic insects associated with these mammals, specifically their physiological adaptations to the marine environment, remains limited. Among thirteen insect species capable of enduring extended underwater periods in open oceans is the seal louse, Echinophthirius horridus, which infests true seals. This species relies on adaptations to survive extreme conditions such as hypoxia, temperature variations, hydrostatic pressure, and drag forces during host dives. These conditions affect both adult lice and louse embryos within their nits. Questions arise about how these early stages survive underwater, respire inside the eggs during dives, and what limits their survival. Using CLSM, SEM, and synchrotron X-ray microtomography, we identified morphological structures consistent with a potentially specialized respiratory system in the nits, a multi-layered eggshell and structural features that may help limit water entry. Adhesive force tests showed that the nit sheath attaching eggs to seal hair is not the primary vulnerability during host dives; rather, prolonged submersion likely imposes oxygen limitation over time. This research enhances our understanding of ectoparasite-host dynamics in marine mammals and demonstrates remarkable adaptability of insects to challenging aquatic niches.
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The White-rumped Vulture is a critically endangered species, facing rapid population declines across South and Southeast Asia due to habitat loss, anthropogenic disturbances, and toxicological pressures. This study uses species distribution modeling (SDM) to assess the current and future habitat suitability for the White-rumped Vulture across its geographic range in the region. We employed MaxEnt, a machine learning algorithm, to model habitat suitability based on 1,248 occurrence records from 2018 to 2024 and 19 bioclimatic, geomorphometric, and anthropogenic variables. The model achieved an excellent Area Under the Curve (AUC) value of 0.937, indicating strong predictive performance. Our results indicate that approximately 20.74% of the study area is currently classified as highly suitable habitat, with India, Pakistan, and Nepal hosting the most significant extents. However, projections for 2040, 2070, and 2100 under two Shared Socioeconomic Pathways (SSPs) SSP 126 (low emission) and SSP 370 (high emission) predict significant habitat loss, particularly under SSP 370, where highly suitable habitat may decrease by up to 60% by 2100. The study also identifies substantial gaps in conservation infrastructure, with over 88% of the highly suitable habitat unprotected. This study highlights the urgent need for region-specific conservation strategies that integrate habitat protection, restoration, and the mitigation of toxicological risks to ensure the long-term survival of the White-rumped Vulture.