Search Results (32)

The Gold-spotted pond frog (Pelophylax chosenicus (Okada, 1931)), classified as an endangered species in South Korea, has experienced significant population declines due to habitat loss, primarily driven by agricultural expansion and urbanization. This study aimed to assess the hibernation ecology of P. chosenicus using PIT tagging technology, focusing on its hibernation behavior, environmental conditions, and implications for conservation and restoration. Over a three-year period (2021–2024), PIT tags were implanted in 408 frogs, enabling continuous monitoring of hibernation sites and individual characteristics. The results revealed that hibernation depths ranged from 1 to 23 cm, with deeper burrowing observed during colder months, indicating a temperature-dependent survival strategy. The soil temperature at hibernation sites remained consistently higher than ambient air temperature, suggesting an adaptive mechanism to avoid freezing conditions. Additionally, frogs exhibited a strong preference for hibernation sites near water bodies, where soil moisture levels were high, highlighting the importance of preserving suitable microhabitats for successful overwintering. These findings provide valuable insights into the hibernation ecology of P. chosenicus and are critical for guiding effective habitat restoration initiatives. Future research should investigate physiological adaptations to varying hibernation environments and the potential impacts of climate change may impact the survival of this endangered species. Full article

Complex associations among production cost factors, multi-source cost information silos, and opaque transmission mechanisms of hidden costs in open-pit coal mining were addressed. The production process—including drilling, blasting, excavation, transportation, and dumping—was taken as the application context. A corpus of 103 open-pit coal mining standards and related research documents was constructed. Eleven entity types and twelve relationship types were defined. Dynamic word vectors were obtained through transformer (BERT) pre-training. The optimal entity tag sequence was labeled using a bidirectional long short-term memory–conditional random field (BiLSTM–CRF) 9 model. A total of 3995 entities and 6035 relationships were identified, forming a symmetry-aware knowledge graph for open-pit coal mining costs based on the BERT–BiLSTM–CRF model. The results showed that, among nine entity types, including Parameters, the F1-scores all exceeded 60%, indicating more accurate entity recognition compared to conventional methods. Knowledge embedding was performed using the TransH inference algorithm, which outperformed traditional models in all reasoning metrics, with a Hits@10 of 0.636. This verifies its strong capability in capturing complex causal paths among cost factors, making it suitable for practical cost optimization. On this basis, a symmetry-aware BERT–BiLSTM–CRF knowledge graph of open-pit coal mining costs was constructed. Knowledge embedding was then performed with the TransH inference algorithm, and latent relationships among cost factors were mined. Finally, a knowledge-graph-based cost factor identification system was developed. The system lists, for each cost item, the influencing factors and their importance ranking, analyzes variations in relevant factors, and provides decision support. Full article

Background/Objectives: Osteoporosis is caused by excessive osteoclast activation via the receptor activator nuclear factor kappa B ligand (RANKL), which is released from osteoblasts or osteocytes. RANKL regulates osteoclast activity by binding to the receptor activator of nuclear factor kappa B (RANK) in the canonical pathway or leucine-rich repeat-containing G protein-coupled receptor 4 (LGR4) in the non-canonical pathway. In this study, we attempted to develop an intact small-fragment protein based on RANKL by removing the RANK-binding site and transforming the amino acid residues at crucial sites to inhibit osteoclast activity and treat osteoporosis. Methods: We expressed a small-fragment variant of RANKL as a soluble glutathione S-transferase (GST) or 6x histidine (His)-tagged fusion protein using a GST- or His-binding domain tag expression vector system. To generate an intact form of small-fragment RANKL, ribosome-inactivating protein–His-fusion RANKL was purified using HisTrap affinity chromatography and treated with tobacco etch virus nuclear inclusion endopeptidase to remove the His-tag fusion protein. Tartrate-resistant acid phosphatase (TRAP) and bone resorption pit formation assays were performed to analyze the inhibitory effects on osteoclast differentiation and activation. Results: The intact forms of 225RANKL295P and 225RANKL295A showed the strongest inhibitory effects on TRAP activity and bone resorption pit formation. Conclusions: Using an optimal construct design, a large and diverse range of small RANKL fragments could be generated. This suggests that the generation of small-fragment RANKL provides a promising avenue for the advancement of novel therapeutic approaches to osteoporosis. Full article

To address the challenges in multimodal information integration and the inefficiency of knowledge transfer in the construction technology disclosure of deep foundation pit projects, an intelligent generation method based on graph rule reasoning and template mapping was proposed. First, a multi-level domain knowledge structure model was constructed by designing domain concepts and relationship types using the Work Breakdown Structure (WBS). Second, entity and attribute extraction was performed using regular expressions and the BERT-BiLSTM-CRF model, while relationship extraction was conducted based on text structure combined with the BERT-CNN model. For image and video data, cross-modal data chains were built by adding keyword tags and generating URLs, utilizing semantic association rules to form a multimodal knowledge graph of the domain. Finally, based on graph reasoning and template mapping technology, the intelligent generation of construction disclosure schemes was realized. The case verification results showed that the proposed method significantly improved the structural integrity, procedural logical consistency, parameter traceability, knowledge reuse rate, environmental compliance, and parameter compliance of the schemes. This method not only promoted the standardization and efficiency of construction technology disclosure activities for deep foundation pit projects but also enhanced the visualization and intelligence level of the schemes. Full article

The healing process of full-thickness skin wounds in maraena whitefish (Coregonus maraena) was investigated to provide preliminary insights into the species’ tissue regeneration mechanism and dynamics following mechanical injury-simulating standard aquaculture PIT tagging procedures. A mechanical skin injury was induced on the dorsal flank of one-year-old maraena whitefish using a 15G needle, and skin regeneration was tracked for 15 days post-wounding (dpw). Expression levels of six genes involved in immune response and inflammation (IL-17D and CD-4), cellular stress response (HSP-90), and cell proliferation and tissue growth (MMP-9, p53, and TGF-β) were examined in wounded and intact skin tissues, liver, and head kidney. Histological analyses were also performed to monitor wound-healing progression. Histological examination revealed typical fish wound-healing characteristics involving re-epithelialization on the 1st day post-wounding (dpw), acute inflammation on the 3rd dpw, granulation tissue formation and intensive wound remodeling on the 8th dpw, and full tissue regeneration by the 15th dpw. Gene expression analysis revealed dynamic tissue-specific patterns: IL-17D and CD-4 were upregulated early in wounded skin, indicating rapid immune and inflammation activation, while MMP-9 and TGF-β peaked later, supporting tissue remodeling and regeneration. HSP-90 and p53 genes were highly expressed in the mid to late stage of healing, reflecting cellular stress response associated with acute inflammation and a high rate of cell proliferation in wounded skin. Significant transcriptional changes in the liver and head kidney further supported the systemic nature of the wound response and emphasized the importance of immune function in the species’ tissue-repair process. The obtained findings provide novel insights into the mechanisms and dynamics of skin healing in maraena whitefish, potentially supporting the development of improved health management strategies for this species in aquaculture. Full article

Understanding individual movement patterns in stream-resident salmonids is critical for conservation and river management, particularly in Mediterranean streams characterized by high environmental variability. We tagged 997 Mediterranean brown trout (Salmo trutta complex) and conducted an 11-month mark–recapture study using Passive Integrated Transponder (PIT) technology to assess movement behavior in the Flamisell River (Ebro Basin, northeastern Iberian Peninsula). Movements followed a leptokurtic distribution, with 81.8% of the individuals classified as sedentary (median movement = 24.9 m) and 18.2% as mobile (median movement = 376.2 m). Generalized linear models revealed distinct drivers of fish movement for each group. In sedentary trout, movement was mainly influenced by mesohabitat type, season, sex, and body size, with males and larger individuals moving farther. In mobile trout, mesohabitat type, density, and body size were key predictors. Movement patterns were repeatable over time, indicating consistent behavioral tendencies. These results support a bimodal movement strategy and highlight the importance of individual variation. Conservation planning should account for both sedentary and mobile groups to preserve functional and genetic connectivity and improve resilience of Mediterranean streams. Full article

Dams severely affect aquatic environments and block the longitudinal migration of fish. In order to mitigate the negative effects generated by these developments, fish passes, or fishways, are implemented in dams with the purpose of restoring river connectivity and allowing the movement of migrants. Nevertheless, fishways in neotropical areas often face design and construction issues that can reduce their efficiency and selectively disadvantage species with limited swimming capabilities. This study analyzes how a fish ladder on the Paraná River influences the black armored catfish (Rhinelepis aspera), a benthic, long-distance migratory species important to commercial fisheries. A total of 200 individuals were PIT-tagged and monitored for four months. The results showed that although many fish successfully located the fishway, only a small portion (3.5%) managed to complete the ascent. The interaction between the hydraulic characteristics of the fishway and the fish condition factor played a significant role in ascent performance. Our findings underscore the importance of assessing fishway suitability for benthic neotropical species to support conservation efforts in the Upper Paraná River Basin. To improve passage rates for R. aspera, we recommend optimizing flow conditions by adjusting orifice and notch configurations, incorporating roughness elements, and modifying resting pool designs. These adaptations would reduce energy expenditure for ascending fish, enhancing fishway performance and contributing to the sustainability of migratory species in this region. Full article

Telemetry techniques are important tools in freshwater fish ecology but are limited by the size of the fish in relation to the size of the electronic tags. The emergence of very small PIT tags (8 mm, mini PIT tags) opens the door to study the individual movement and behavior of small-sized fish species and life stages previously outside the scope of fish telemetry. Although high survival from mini PIT tags have been shown in some groups of fish, suitability assessments are lacking for many taxa, and potential behavioral effects have rarely been evaluated. Here, we evaluate the survival tagging effects in small-sized (35–76 mm) Padanian goby (Padogobius bonelli) implanted with mini PIT tags. PIT-tagging was associated with high survival and tag retention in the tagged fish. No effects of PIT-tagging on volitional swimming activity nor on maximum swimming speed were found. Similar results were obtained implanting larger tags (12 mm) in gobies down to 50 mm in length. Our results indicate that PIT telemetry—using mini PIT tags—is applicable for the study of behavior and movement in small-sized gobies. Full article

Freshwater mussel populations are in sharp decline and are considered to be one of the most imperilled groups globally. Consequently, the number of captive breeding programmes has increased rapidly in recent years, coupled with subsequent reintroductions/population reinforcements to reverse these declines. The outcomes of mussel conservation translocations are seldom reported in the primary literature, hindering opportunities for learning and for population recovery at pace. Here, we describe the methods employed to carry out a successful conservation translocation of the freshwater pearl mussel (Margaritifera margaritifera) in a declining population in northwest England. Following a small-scale pilot release in 2017, four release sites were identified for a population reinforcement of over 1300 tagged mussels in 2021. Monitoring during 2022 showed high levels of retention of juveniles at three out of the four release sites, despite the occurrence of a significant flood event during October 2021. Subsequent releases of 1100 juveniles were carried out across the three successful sites in 2023. Ongoing and regular monitoring is essential in order to provide data on the longer-term fate of propagated juveniles in the wild. This will allow for adaptive management of release activities in this river. These data will be useful to design conservation translocation strategies for other imperilled pearl mussel populations in the UK and throughout Europe. Full article

Connectivity is critical for stream fish persistence, and fish passage structures are a useful conservation tool to reconnect fragmented systems. The design of fish passage structures is a tradeoff between the area available for construction, slope, and costs associated with the structure. The Longrie–Fecteau fish passage structure was designed to be modular, adjustable to barrier-specific needs, and to have a low slope (2%) to pass small-bodied fishes. We evaluated fish passage through this structure in Fountain Creek, Colorado, USA, via a PIT tag mark–recapture study. We documented four native Great Plains fish species successfully ascending the passage structure, with most passage occurring at night. We estimated a 3% probability of a released fish entering the structure, then 89% and 99% passage to the midpoint and exit of the 123 m structure, respectively. Low entrance efficiency was due to low recapture probability of small-bodied study organisms in a relatively large system, and the low percentage of space of the entryway on this barrier (<3% of the length of the barrier). Fish that entered the structure ascended quickly, with median time for successful ascent of 19 min, and minimum time of 6 min. The Longrie–Fecteau fish passage structure is a conservation tool that may broaden the adoption of fish passage structures for small-bodied fishes due to its modularity and low slope. Full article

β-arrestins are multifaceted adaptor proteins that regulate various aspects of G protein-coupled receptor (GPCR) signaling. β-arrestins are recruited to agonist-activated and phosphorylated GPCRs at the plasma membrane, thereby preventing G protein coupling, while also targeting GPCRs for internalization via clathrin-coated pits. In addition, β-arrestins can activate various effector molecules to prosecute their role in GPCR signaling; however, the full extent of their interacting partners remains unknown. To discover potentially novel β-arrestin interacting partners, we used APEX-based proximity labeling coupled with affinity purification and quantitative mass spectrometry. We appended APEX in-frame to the C-terminus of β-arrestin1 (βarr1-APEX), which we show does not impact its ability to support agonist-stimulated internalization of GPCRs. By using coimmunoprecipitation, we show that βarr1-APEX interacts with known interacting proteins. Furthermore, following agonist stimulation βarr1-APEX labeled known βarr1-interacting partners as assessed by streptavidin affinity purification and immunoblotting. Aliquots were prepared in a similar manner and analyzed by tandem mass tag labeling and high-content quantitative mass spectrometry. Several proteins were found to be increased in abundance following GPCR stimulation. Biochemical experiments confirmed two novel proteins that interact with β-arrestin1, which we predict are novel ligand-stimulated βarr1 interacting partners. Our study highlights that βarr1-APEX-based proximity labeling represents a valuable approach to identifying novel players involved in GPCR signaling. Full article

Fragmentation of rivers through anthropogenic modifications poses an imminent threat to the persistence of migratory fish, necessitating direct actions such as trap-and-haul programs to restore and conserve the migratory life-history component in populations of partially migratory species such as bull trout Salvelinus confluentus. We used a PIT-tag system to assess how biological and abiotic factors influence the out-migration dynamics of juvenile bull trout in Graves Creek, Montana, USA. The largest fish within a cohort were more likely to out-migrate at age 1 when compared to smaller fish within the cohort, and this was particularly evident in a high-density year-class (2018), where large bull trout out-migrated an average of 115 days earlier than bull trout in the medium size category, and 181 days earlier than bull trout in the small size category. Relative changes in abiotic factors, including discharge, water temperature, and photoperiod, appeared to act as cues to out-migration, with the direction of change varying by season. These results highlight the complex interplay between individual characteristics, population dynamics, and environmental conditions, which influence out-migration dynamics and can be used to inform management actions to conserve the migratory component in bull trout populations. Full article

Wildlife tracking is used to acquire information on the movement, behaviour and survival of animals in their natural habitat for a wide range of ecological questions. However, tracking and monitoring free-ranging animals in the field is typically labour-intensive and particularly difficult in species that are small, cryptic, or hard to re-capture. In this paper, we describe and evaluate an Internet-of-Things (IoT)-based tracking system which automatically logs detected passive RFID tags and uploads them to the cloud. This system was successfully evaluated with 90 sensor modules deployed in a 30 ha wildlife sanctuary to monitor a small nocturnal mammal of less than 20 g in body size. Full article

The utility of environmental DNA (eDNA) as a detection tool for fisheries management is limited by dilution and degradation, especially in areas of low fish abundance. This proof-of-concept study addressed these challenges by testing whether food or pheromones might be used to attract invasive carp so they can be measured more readily using eDNA. In two experiments, PIT-tagged carp were stocked into ponds (N = 3 for silver carp; N = 1 for common carp) while one of two stimuli (planktonic food [spirulina] for silver carp and a sex pheromone [prostaglandin F2α] for male common carp) was added to determine if we could attract fish to one side while measuring both fish presence (detections) and eDNA concentrations. The addition of spirulina increased detections of silver carp by 2–3 fold, while eDNA concentrations increased by 4-fold on the test side when compared to the side without the stimulus. The addition of the sex pheromone increased detections of common carp by ~25-fold, where a 6-fold increase in eDNA concentrations was measured (p < 0.05). A strong positive correlation was noted between fish presence and eDNA concentration for both species. These experiments demonstrate that food and pheromone stimuli could be used to attract invasive carp so they could be measured more easily and accurately. Full article

The aim of this project is to promote the recovery of ecological connectivity within 10–20 years in the lower Ebre River and Delta, and a healthy and sustainable population of diadromous fish, including European sturgeon (Acipenser sturio), European eel (Anguilla anguilla), twaite shad (Alosa fallax) and sea lamprey (Petromyzon marinus), among other aquatic native species. It is focused on long-term sustainable investments, adapting all present river obstacles to allow fish migration, increasing the river spawning habitat availability and the distribution and growth areas of migrating fish. The main activities of the LIFE MIGRATOEBRE Project (LIFE13 NAT/ES/000237) are: (1) Build a fish ramp at Xerta’s weir (located at 58 km from the Mediterranean sea; in 2023), and a fish ramp at Ascó’s weir (located at 104 km from the sea; built in 2017), and monitor them regularly. (2) Apply ship locks fish-friendly improved management at Xerta’s weir (located at 56 km from the sea), and monitor it regularly. (3) Undertake a pilot project of European sturgeon restocking through an experimental release in the lower Ebre (in 2023). (4) Develop a communication campaign and a community involvement plan for students, the general public, farmers, fishermen, anglers, electric companies, tourism stakeholders and regional and local authorities. This included the production of a great temporary exhibition and a network of volunteers. The potential spawning and feeding areas for European sturgeon, twaite shad and sea lamprey were identified and cartographed. Extensive monitoring of the target fish population of the lower Ebre river was carried out (2000 fish were marquet with PIT tags). Between 2017 and 2020, 150 fish (Chelon labrosus, Mugil cephalus, Alosa fallax and Anguilla anguilla) were monitored by acoustic telemetry (using 47 Vemco receivers located along the river and at in the lagoons of the Ebre delta). Obtained results indicate that the Ebre is optimal for the recovery of the target species of this project, but at the same time it would be very important to carry out a control of invasive species. This LIFE project started on 1 July 2014 and, after several extensions, it will finish on 30 June 2024. More information can be found at: www.migratoebre.eu. Full article