Eriksson CE et al. · Jul 1, 2026
Noninvasive genetic sampling is widely used in ecology and conservation to identify predators and their diets but recovering individual-level information from consumed prey remains largely unexplored. We evaluated whether individual prey can be reliably genotyped from carnivore scats and assessed limitations associated with degraded and mixed DNA sources. We developed a 31-locus SNP panel optimized for genotyping degraded elk (Cervus canadensis) DNA using amplicon sequencing. We validated prey genotyping by matching elk genotypes recovered from carnivore scats ('carcass scats') collected at cougar (Puma concolor) kill sites to genotypes from corresponding elk carcasses. We also genotyped scats collected throughout the study area, identified as containing elk using DNA metabarcoding ('survey scats'). To avoid misidentifying multiple individuals in a scat as a unique genotype, we evaluated artificial mixtures of prey DNA to assess the ability to detect and filter samples containing mixed DNA. Elk genotypes recovered from carcass scats matched associated carcass genotypes, confirming accurate recovery of individual prey DNA from carnivore scats. Genotyping success was 88% in fresh carcass scats and 74% in survey scats of unknown age. Heterozygosity excess filtering removed most mixed samples, although one of 24 mixtures with equal DNA contributions from two individuals produced a false unique genotype. Our results demonstrate that carnivore scats can serve as a reliable source of individual-level prey DNA under appropriate conditions. This method provides a new data stream on individual prey mortality, predation rates, and scavenging dynamics, processes that have previously been difficult to quantify without invasive capture and collaring techniques.
Environmental Science
Nigatu EW. · Jul 1, 2026
Background Adaptive traits, along with productive and reproductive performance, are essential for assessing the suitability and long-term sustainability of indigenous cattle in specific production environments. Objective This study evaluated the adaptive, productive and reproductive performance of Boran dairy cattle in the lowland agro-ecology of the Kaffa Zone, south-western Ethiopia. Methods The study was conducted at a commercial farm in Gojeb, and sixty (60) multiparous Boran dairy cows were selected based on health status, parity, and lactation stage, following an adaptation period before data collection. This study covered the early, mid and late lactation stages over a 25-week monitoring period. Daily milk yield was recorded twice daily, and reproductive parameters, including age at first calving (AFC), calving interval (CI), number of services per conception (NSPC), days open (DO) and gestation length (GL), were obtained from farm records. Adaptive performance was assessed using rectal temperature (RT) and respiration rate (RR) in relation to the meteorological variables. Blood samples were collected from 30 cows (10 per lactation stage) for haematological (HC, RBC, WBC and PCV) and biochemical (TP, GLU, URE, TGL, TC, AST and ALT) analyses. Data were analysed using SPSS version 20, and descriptive statistics were summarized as mean ± SD. Results The current study revealed that the mean daily milk yield was 2.43 ± 0.62, 2.12 ± 0.58 and 1.72 ± 0.45 L/day for early, mid and late lactation, respectively. Parity 1 and 2 cows produced 1.71 ± 0.46 L and 2.47 ± 0.52 L, respectively, with an overall mean of 2.09 ± 0.62 L/day. Parity and lactation stage significantly (p Conclusion The productive and reproductive performances of Boran cows were within the expected ranges for indigenous breeds, suggesting that crossbreeding could enhance productivity. Further studies should consider age, season and comparisons with other locally adapted breeds.
Environmental Science
Kim S et al. · Jul 1, 2026
Education for sustainable development (ESD) is increasingly recognized as a developmental imperative in a world facing ecological, social, and political challenges. While many approaches to ESD emphasize knowledge and competencies, emerging research suggests that sustainable action in youth requires the integration of cognitive, emotional, and identity-based developmental processes. We propose that Digital Civic Learning (DCL) serves as a developmentally appropriate educational approach that can scaffold this process in early adolescence. Using a sample of 149 4th and 5th graders in Mid-Western United States, we examined how civic competencies, namely civic knowledge, skills, and dispositions, relate to civic purpose and further investigated the mediating role of moral self-concept. Our findings underscore the importance of nurturing moral self-concept so that enhanced civic competencies translate into a form of civic purpose. SUMMARY: Conceptual innovation: It introduces Digital Civic Learning as a design-based, developmentally aligned model that integrates civic learning with sustainable development goals, aiming for transformative impact in education. Methodological advancement: It develops and applies a novel civic competencies coding scheme tailored for a nuanced analysis of students' civic knowledge, skills, and dispositions. Theoretical contribution: It positions moral self-concept as a developmental link connecting civic learning with a sustainability-oriented civic purpose in early adolescence, a critical period for identity formation. Empirical rigor: It employs performance-based assessments to evaluate students' civic competencies demonstrated in authentic digital classroom settings, emphasizing real-world application of civic reasoning within sustainability education.
Environmental Science
Pandey N et al. · Jul 1, 2026
Background and aims Increasing reports of plastic accumulation in human tissue have raised concerns about potential adverse health outcomes. Evidence of negative effects of nanoplastics is heterogeneous and provides limited insights into the underlying pathogenic toxicity mechanisms in humans. Methods In the present study, carboxylate-modified fluorescently labelled polystyrene nanoparticles (PS NPs) were used to investigate uptake and cytotoxicity in three different hepatic models of varying complexity, including HepG2 cells, IHH cells, and human precision-cut liver slices (hPCLS). Results The results show model- and dose-dependent effects on hepatocytes. 74.2% ± 13.4% of the IHH cells showed PS NPs uptake at 0.1 μg/mL, which is considerably lower than the estimated plastic concentration in human blood (1.8-4.7 μg/mL). The viability of IHH cells decreased to 10.6% ± 9.1% after exposure to 100 μg/mL for 48 h. Early signs of hepatic injury were found in hPCLS at high concentrations. No changes were observed in the redox state and mitochondrial respiratory parameters of HepG2 cells after exposure. Conclusion The PS NPs exposure experiments show uptake across all three hepatic models and toxic effects in IHH cells and hPCLS. Overall, the study highlights the need for physiologically relevant human tissue models to understand the impact of nanoplastic pollution on human health.
Environmental Science
Bahman F et al. · Jul 1, 2026
Background The aryl hydrocarbon receptor (AhR) is linked to inflammation, but its plasma agonist activity and association with metabolic and inflammatory markers in obesity remain unclear. This cross-sectional study aimed to determine the level of plasma AhR agonistic activity and its association with systemic inflammation and metabolic dysregulation in obesity. Methods Plasma samples were collected from 80 non-diabetic (39-obese, 23-overweight, and 18-normal/healthy weight) individuals. AhR agonist activity was assessed using a cell-based luciferase reporter assay. Plasma AhR was quantified by ELISA. Inflammatory markers were assessed using a multiplex Luminex platform. Results Our findings indicate that plasma AhR agonist activity is elevated in obese (92.77 ± 4.002 fold activation) compared with normal/healthy weight (51.39 ± 2.335) and overweight participants (67.54 ± 5.24 fold activation). Moreover, the AhR protein was also elevated in obese (94.88 ± 7.62 pg/ml) compared to normal/healthy weight (65.88 ± 6.78 pg/ml) and overweight participants (67.54 ± 5.24 pg/ml), which was positively correlated with AhR activity (r = 0.441, p Conclusions Our findings demonstrate that elevated plasma AhR agonist activity is associated with obesity, systemic inflammation, and metabolic dysregulation. These results highlight AhR activity as a biomarker of interest and support further studies to clarify its mechanistic role and potential clinical relevance in metabolic disorders.
Environmental Science
de Boer RJ et al. · Jun 22, 2026
Patients infected with life-threatening multi-drug resistant (MDR) bacteria have been treated with cocktails of bacteriophages. This is a complicated form of personalized medicine as the phages given to a patient have to be selected beforehand on the basis of their lytic capacity of the infecting bacteria. Because bacteria rapidly become resistant, the evolution of resistance to a diverse cocktail of phages is a complicated dynamical process, during which competing bacterial strains replace one another by accumulating several resistance mechanisms, each of which may involve a fitness cost. As a consequence, it is typically not known why a particular phage therapy succeeded or failed, and how one can optimize the composition of the cocktails to maximize the rate of success. To improve upon this, we extend an existing in vivo-calibrated mouse model into a novel mathematical model for the human situation, and include multiple phages infecting multiple bacterial strains, differing in their resistance to each of the phages. We adjust several parameter estimates of the bacterial model to the human situation, and use the model to describe a successful case of phage therapy involving several cocktails, each containing several phages. In the model, treatment success crucially depended on pretreatment resistance levels, and on the diversity and the timing of the cocktails. Once an appropriate cocktail is found, it is less important to further optimize the infection rates of the phages. Resistant bacterial strains expand rapidly when sensitive strains decline, and the higher the infectivity of the phages, the faster resistant strains expand. Because resistance evolves rapidly, it is best to provide a diverse set of phages right from the start of therapy, i.e., to hit hard and early, and create a high genetic barrier to bacterial resistance.
Environmental Science