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The Role of Horses as Instructional and Diagnostic Partners in Riding Lessons
Get PDFIn many types of embodied skills instruction, the learnables-that is, the local and jointly negotiated foci of instruction-emerge from a combination between a pre-existing lesson plan and the spontaneous interaction between teacher and student. Through the analytical lens of Conversation Analysis, this paper investigates the interspecies instruction setting of horse-riding lessons and shows how here, it is not only the human teachers and learners that determine the emergence of new learnables but also the horses. Horses' actions can initiate new courses of action in a lesson, and horses can thus become interactional partners in the instructional project. Horse-led learnables can be initiated in at least three ways: through horses' displays of mental or physical states that pre-date the instruction sequence; through actions that respond to local contingencies of the instruction sequence; and through actions that respond specifically to the rider's actions. In the last case, their responses become diagnostic of the rider's mistakes. In all three cases, the human participants take their cue from the horse and base new learnables on horses' actions. Human-led learnables can be adjusted, changed, replaced, or abandoned completely in response to horses. The study broadens the emerging field of interspecies pragmatics to include instructional interactions involving the triad of human-human-horse triad
"Shape of Cell"-An Auxin and Cell Wall Duet
Get PDFUnderstanding the mechanisms underlying cell shape acquisition is of fundamental importance in plant science, as this process ultimately defines the structure and function of plant organs. Plants produce cells of diverse shapes and sizes, including pavement cells and stomata of leaves, elongated epidermal cells of the hypocotyl, and cells with outgrowths such as root hairs, and so forth. Plant cells experience mechanical forces of variable magnitude during their development and interaction with neighboring cells and the surrounding environment. From the time of cytokinesis, they are encaged in a complex cell wall matrix, which offers mechanical support and enables directional growth and a differential rate of expansion towards adjacent cells via its mechanochemical heterogeneity. The phytohormone auxin is well characterized for its role in cell expansion and cell elasticity. The interaction between dynamic auxin redistribution and the mechanical properties of the cell wall within tissues drives the development of specific cell shapes. Here, we focus on the regulatory feedback loop involving auxin activity, its influence on cell wall chemistry and mechanical properties, and the coordination of cell shape formation. Integrating insights from molecular and cell biology, biophysics, and computational modeling, we explore the mechanistic link between auxin signaling and cell wall dynamics in shaping plant cells
Host identity, nest quality, and parasitism strategy: influences on body size variation in parasitoid bees and wasps
Get PDFBody size determines mobility and fitness across taxa in various ways. Yet, drivers of body size in higher trophic invertebrates, especially parasitoids, including intra- and interspecific variations, are poorly understood due to complex interactions between parasitoid behaviour, the environment and their hosts. We measured the body size of 393 individuals of four parasitoid species (collected from 2220 parasitized brood cells) sampled with trap nests for cavity-nesting bees and wasps in the Southern Black Forest, Germany. We related parasitoid body size to the size of 15 host species and the diameters of their nests along five environmental gradients (proportion of conifers, canopy cover, structural complexity, herb cover and deadwood diameter). Host identity, nest diameter, and to a lesser extent, size differences within host species were primary drivers of parasitoid body size, albeit responses varied among parasitoid species. For instance, when the host black wood borer wasp Trypoxylon figulus doubled in size, the ichneumon wasp Nematopodius debilis (parasitising the host directly) increased by 37% in size, while the blue cuckoo wasp Trichrysis cyanea (parasitising food resources) increased by only 8%. Across host-parasitoid species combinations, parasitoid size correlated weakly with host size, and environmental gradients did not significantly influence host or parasitoid body size. Our findings highlight the primary factors influencing body size, with host identity and nest diameter emerging as influential factors within and between parasitoid species, although not uniformly. In contrast, the relationship between the top trophic level (parasitoids), the lower trophic level (hosts), and host size with environmental gradients were less influential. Considering the environmental variables that directly affect body size, such as microhabitat conditions and biotic interactions, may further clarify the dynamics shaping the variation in body size at higher trophic levels and should be considered in future studies addressing how land management influences multitrophic interactions
Genome Sequence Resources from Three Isolates of the Apple Canker Pathogen Neonectria ditissima Infecting Forest Trees
Get PDFNeonectria ditissima is a generalist ascomycete plant pathogen causing canker diseases on a variety of hardwood tree species and can cross-infect many of them. The fungus enters the plants through wounds throughout the year. N. ditissima is considered a major threat to apple production responsible for the fruit tree canker disease, which damages trees and causes rotting of fruits in storage. Nearby forests and shelter belts can serve as sources of inoculum for well-managed apple orchards. Thus, knowledge about the N. ditissima isolates infecting different host species is essential for designing integrated pest management strategies. Here, we describe the genomes of three N. ditissima isolates, Nd_iso34, Nd_iso35, and Nd_iso36, infecting European beech, American tulip tree, and American beech, respectively. We obtained genome assemblies of approximately 45 megabases for all isolates, covering 94% of the N. ditissima reference annotation, and 97% of the universal single-copy orthologs (BUSCOs). We conclude that these genome assemblies are a highly relevant resource considering the scarcity of genomic data available for N. ditissima.Copyright (c) 2025 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license
Microalgae: A Solution for Food Security and Multiplanetary Farming
Get PDFHuman civilization is threatened by food insecurity and habitat loss owing to the cumulative effects of anthropogenic and natural factors. Thus, increasing food production while using fewer resources and exploring the potential of interstellar migration is essential. Particularly, microalgae can fulfil the biological, nutritional, and efficiency requirements of industrial food production on Earth and other potential planets. Herein, we discuss the industrial production of microalgae on Earth and in outer space, along with the technological advances that will help reshape the genetic and chemical properties of microalgae for better production, nutrition, and adaptation. We propose the concept of "multiplanetary farming" to address future requirements for agricultural development. This perspective review is intended to stimulate a broad debate and research on this paramount issue for the future of mankind
Seasonal rainfall patterns affect rainfed maize production more than management of soil moisture and different plant densities on sandy soils of semi-arid regions
Get PDFIn semi-arid regions, erratic rainfall and water losses through percolation are causing low yields of rainfed maize (Zea mays L.) grown on sandy soils. This study evaluated the effects of soil moisture management and different plant densities across four cropping seasons on rainfed maize performance. The study was conducted on a smallholder farm with sandy soils in a semi-arid district of Mutare, Zimbabwe. In a split-plot experimental design, low-density polyethylene membranes installed below the root growth zone known as sub-surface water retention technology (SWRT) and the control were main treatments and three different plant densities were subtreatments. Maize performance including plant height, leaf chlorophyll, biomass and grain yields and rainwater use efficiency (RWUE) were monitored. Results showed that, while SWRT significantly increased maize grain yield by 21 % and total biomass yield by 13 % across seasons, this effect was smaller than that caused by the seasonal rainfall variation. In wet years, maize grain yield ranged from 3.0 to 5.8 t ha- 1, while in dry years, it ranged from 0.7 to 1.2 t ha- 1. RWUE of the maize increased significantly with plant density and was higher in dry (305 mm) compared to wet (780 mm) seasons. This study provides evidence of the need to optimize available water resources to increase maize grain yields under semi-arid conditions through integrated soil moisture management and optimised maize planting densities. It also highlights the need to invest in water harvesting and irrigation infrastructure to improve control over water resources and facilitate higher yields and yield stability
Estimating landscape-level water storage potential as a tool to mitigate floods and nutrient losses
Get PDFExtreme weather events, which are becoming more frequent due to climate change, result in intensified nutrient losses and may override effects of agricultural mitigation measures. Using a landscape connectivity approach, we study the potential of water flow attenuation in upstream forest areas to prevent or mitigate waterlogging and flooding of downstream arable land, thereby contributing to reduced phosphorus (P) losses. We use soil distribution maps, high-resolution elevation data, land use maps and distributed modelling to quantify water storage potential and possible P reductions. In three out of four study catchments (119-915 km2), calculated storage potential of detention basins located in upstream wetland and forest areas was sufficient to retain water volumes (0.7-3.6 million m3) corresponding to discharge volumes produced during an episode with a 50 -year return period. Furthermore, it was estimated that 9-57 % of targeted annual P load reductions from arable land could be reached if stored water volumes bypass arable land without causing waterlogging/flooding leading to P mobilization and transport. As water storage potential is site-specific, prioritization and selection criteria need to be developed in collaboration with relevant stakeholders to achieve cost-efficient implementation of these measures. The methodology and results of this study have significant potential for application in landscapes with a mixture of forests and arable agriculture to aid land owners and managers to secure food production and improve water quality
Urinary Cystatin C, Glucose, Urea, and Electrolytes in Dogs at Various Stages of Chronic Kidney Disease
Get PDFBackgroundThere is limited knowledge of urine analytes in different stages of chronic kidney disease (CKD) in dogs.ObjectivesTo study markers in urine and fractional excretion (FE) of markers in dogs of different stages of CKD and a healthy control group (C).AnimalsFifty dogs in various stages of CKD and a control group of 30 healthy dogs.MethodsIn this cross-sectional observational study, dogs presenting to a referral hospital and given a diagnosis of CKD using standard methods, and healthy dogs, were included. Urinary cystatin C (uCysC), glucose (uGlu), protein (uProt), creatinine (uCr), urea (uUrea), sodium (uNa), potassium (uK), chloride (uCl), calcium (uCa), and phosphate (uP) were measured with an automated chemistry analyzer. Included analytes were normalized to uCr, FE of electrolytes and urea was calculated, and results compared among groups.ResultsAge, bodyweight, and sex were not different among groups. Urinary CysC/uCr and FE of electrolytes increased with IRIS stage. Median (IQR) for uCysC/uCr was 0.08 (0.04-0.25) 10-3 in dogs with CKD stage 1 and 0.03 (0.02-0.045) 10-3 in control dogs (p = 0.0002).Conclusion and Clinical ImportanceUrinary CysC might be a potential marker of early CKD, preferably as part of a panel of urinary markers. FE of electrolytes seemed to depend on the serum creatinine level in dogs with azotemic CKD
Fish functional groups of the North Atlantic and Arctic oceans
Get PDFInternational efforts to assess the status of marine ecosystems have been hampered by insufficient observations of food web interactions across many species, their various life stages, and their geographic ranges. Hence, we collated data from multiple databases of fish stomach contents from samples taken across the North Atlantic and Arctic oceans containing 944 129 stomach samples from larvae to adults, with 14 196 unique interactions between 227 predator species and 2158 prey taxa. We use these data to develop a reproducible data-driven approach to classifying broad functional feeding guilds and then apply these to fish survey data from the north-east Atlantic shelf seas to reveal spatial and temporal changes in ecosystem structure and functioning. In doing so, we construct individual predator-prey body-mass scaling models to predict the biomass of prey functional groups, e.g. zooplankton, benthos, and fish, for different predator species. These predictions provide empirical estimates of species- and size-specific feeding traits of fish, such as predator-prey mass ratios, individual prey mass, and the biomass contribution of different prey to predator diets. The functional groupings and feeding traits provided here help to further resolve our understanding of interactions within marine food webs and support the use of trait-based indicators in biodiversity assessments. The data used and predictions generated in this study are published on the Cefas Data Hub at 10.14466/CefasDataHub.149 (Thompson et al., 2024)
Trends and purposes of European river monitoring and restoration
Get PDFThis study provides the first geospatial analysis of the trends and uptake of European river monitoring and restoration. European monitoring targets rivers draining agricultural and urban land, which leads to geospatial biases due to the co-occurrence with soils, topography, and river orders. Most notably, intermittent rivers and ephemeral streams are underrepresented due to lower monitoring intensities in Southern Europe, headwaters, and catchments with steeper slopes or less arable soils. Improving monitoring efforts in these ecosystems can advance our scientific understanding of complex linkages between ecological quality outcomes and specific stressors. Large differences were found in the spatial coverage of river monitoring and chemical status reporting between European river regions, which highlights comparability issues with the outcomes of Water Framework Directive river quality status due to the 'one-out-all-out' principle. Chemical status monitoring is also less frequent in agricultural catchments, which leads to a knowledge gap on the impacts of priority substances, such as pesticides, on agricultural rivers. These uncertainties around the actual quality of rivers are propagated to the prioritisation, design and purposes of river restoration. River restoration coverage is distinctively higher in Western Europe and larger urban rivers, compared to lower incidences in headwaters draining agricultural or (semi-)natural catchments. Across most regions and geospatial factors, biodiversity conservation was the major purpose for river restoration. Agricultural headwaters and intermittent rivers are low-hanging fruits for future river restoration, wherein socio-economic drivers of river restoration can be leveraged to achieve parallel goals of biodiversity and water resource management