Long-term Trapping Research Articles

The moon's influence on the activity of tropical forest mammals.

Changes in lunar illumination alter the balance of risks and opportunities for animals, influencing activity patterns and species interactions. We examined if and how terrestrial mammals respond to the lunar cycle in some of the darkest places: the floors of tropical forests. We analysed long-term camera trapping data on 86 mammal species from 17 protected forests on three continents. Conservative categorization of activity during the night revealed pronounced avoidance of moonlight (lunar phobia) in 12 species, compared with pronounced attraction to moonlight (lunar philia) in only three species. However, half of all species in our study responded to lunar phases, either changing how nocturnal they were, altering their overall level of activity, or both. Avoidance of full moon was more common, exhibited by 30% of all species compared with 20% of species that exhibited attraction. Nocturnal species, especially rodents, were over-represented among species that avoided full moon. Artiodactyla were more prominent among species attracted to full moon. Our findings indicate that lunar phases influence animal behaviour even beneath the forest canopy. Such impacts may be exacerbated in degraded and fragmented forests. Our study offers a baseline representing relatively intact and well-protected contexts together with an intuitive approach for detecting activity shifts in response to environmental change.

High Stability and Low Power Nanometric Bio-Objects Trapping through Dielectric-Plasmonic Hybrid Nanobowtie.

Micro and nano-scale manipulation of living matter is crucial in biomedical applications for diagnostics and pharmaceuticals, facilitating disease study, drug assessment, and biomarker identification. Despite advancements, trapping biological nanoparticles remains challenging. Nanotweezer-based strategies, including dielectric and plasmonic configurations, show promise due to their efficiency and stability, minimizing damage without direct contact. Our study uniquely proposes an inverted hybrid dielectric-plasmonic nanobowtie designed to overcome the primary limitations of existing dielectric-plasmonic systems, such as high costs and manufacturing complexity. This novel configuration offers significant advantages for the stable and long-term trapping of biological objects, including strong energy confinement with reduced thermal effects. The metal's efficient light reflection capability results in a significant increase in energy field confinement (EC) within the trapping site, achieving an enhancement of over 90% compared to the value obtained with the dielectric nanobowtie. Numerical simulations confirm the successful trapping of 100 nm viruses, demonstrating a trapping stability greater than 10 and a stiffness of 2.203 fN/nm. This configuration ensures optical forces of approximately 2.96 fN with an input power density of 10 mW/μm2 while preserving the temperature, chemical-biological properties, and shape of the biological sample.

A CuOx/p+-Si memristor with short- and long-term plasticity for homogeneous reservoir computing system

Reservoir computing (RC) system is a simple and cost-efficient neuromorphic computing system mainly consisting of a reservoir layer and a readout layer. The reservoir layer comprises nonlinear nodes with short-term plasticity (STP), while the readout layer comprises linear nodes with long-term plasticity (LTP). Here, we propose a self-rectifying (>102) memristor based on CuOx/p+-Si heterojunction that exhibits both nonlinear STP and linear LTP characteristics with high uniformity (σ/μ = 2.8 %). The resistive switching of the device is mainly based on electron trapping/detrapping in CuOx film. The trapping before relaxation is very unstable and less capable of long-term trapping, which leads to STP. The trapping after relaxation is relatively stable for the lowered trap barrier, which induces LTP. Utilizing its dynamic STP characteristics for the reservoir layer and LTP properties for the readout layer, a CuOx/p+-Si memristor-based homogeneous dynamic RC system was constructed for a spoken-digital recognition task, yielding an accuracy rate of 95.33 %. These results affirm the tremendous potential of our device in establishing a highly compact and full-memristor-based homogeneous RC system.

Seasonal migrations and morphometry of the European Nightjar according to long-term (1957–2016) trapping and ringing in the Eastern Baltic

The results of trapping, measuring the size and weight of the body of the European Nightjar, as well as migration routes according to the data of the ringing in the Kaliningrad region during 1957–2016 are discussed. The annual number of migrating birds has fluctuated significantly for 60 years, and the number of those caught and ringed varied from one to 44 individuals in different years. They were most numerous in May, in the period 1969–1981. Four ring recoveries of Nightjars ringed by us were obtained, which gives the effectiveness of ringing of this species with nocturnal activity of only 0.92%. However, these ringing results indicate that in autumn the migration routes of Nightjar population from the western parts of Scandinavia and from southern Finland run through the eastern coast of the Baltic Sea, and later, on the way to Africa, their azimuth of flight varies from 178° to 203°. The longevity record according to the data from one male of the subspecies Caprimulgus europaeus zarudny E. Hartert, 1912 was 15 years. The migration routes of this species are discussed according to the latest literature data.

Engaging Citizen Scientists in Biodiversity Monitoring: Insights from the WildLIVE! Project

The growing public interest in biodiversity monitoring has led to a significant increase in initiatives that unite citizen scientists, researchers, and machine learning technologies. In this context, we introduce WildLIVE!, a dynamic biomonitoring and citizen science project. In WildLIVE!, participants analyze a vast array of images from a long-term camera trapping project in Bolivia to investigate the impacts of shifting environmental factors on wildlife. From 2020 to 2023, more than 850 participants registered for WildLIVE!, contributing nearly 9,000 hours of voluntary work. We explore the motivators and sentiments of participant engagement and discuss the key strategies that have contributed to the project’s initial success. The findings from a questionnaire highlight that the primary motivational factors for our participants are understanding and knowledge, as well as engagement and commitment. However, expressions of positive and negative sentiments can be found regarding involvement. Participants appeared to be driven primarily by a desire for intellectual growth and emotional fulfillment. Factors crucial to the success of this digital citizen science project include media exposure, creating emotional connections through virtual and in-person communication with participants, and visibility on public citizen science portals. Moreover, the project’s labeled dataset serves as a valuable resource for machine learning, aiding the development of a new platform that is compliant with the FAIR principles. WildLIVE! not only contributes to outcomes in science, society, and nature conservation, but also demonstrates the potential of creating a collaborative bridge between the general public, scientific research, biodiversity conservation, and advanced technological applications.

Characterization of Current Collapse and Enhancement of Hydrogen-Terminated Diamond MOSFET Due to Long-Term Trapping Effects

Characterization of Current Collapse and Enhancement of Hydrogen-Terminated Diamond MOSFET Due to Long-Term Trapping Effects

Long-term mercury loading and trapping dynamics in a Western North America reservoir

Study RegionThe Carson River including Lahontan Reservoir in Northwestern Nevada, USA Study FocusThe discovery, mining, and processing of silver and gold from the Comstock Lode in northwestern Nevada heavily contaminated the Carson River system with mercury (Hg). The river now contains some of the highest recorded water column and bed sediment Hg concentrations reported in peer-reviewed literature. Acute Hg contamination in river and reservoir bed sediment has led to elevated methylmercury (MeHg) concentrations across all trophic levels of Lahontan Reservoir, culminating in significant health risks to humans. Lahontan Reservoir, located downstream from the mills that processed Comstock ore, has served as a Hg trap since the completion of the dam in 1915. Starting in 1997 and extending through 2021, the U.S. Geological Survey has collected and analyzed hundreds of discrete water samples entering and exiting Lahontan Reservoir for unfiltered total Hg (uf.THg), thereby providing a first-of-its-kind opportunity for studying long-term Hg trapping efficiencies within a western North American reservoir. Continuous time series of uf.THg concentration and flux above and below the reservoir were estimated using the weighted regressions on time, discharge, and season with the Kalman filtering (WRTDS-K) method employed with newly developed methods to account for non-natural (i.e., managed) hydrographs below a reservoir. New hydrological insights for the regionAn estimated 31,650 kg (34.89 US tons) of uf.THg entered Lahontan Reservoir during the 25 year period of analysis, accounting for approximately 0.5% of the total uf.THg estimated to have been released to the Carson River system [6.8 million kg (7500 US tons)] over a multi-decade mining boom. Moreover, approximately 92% of the estimated uf.THg entering Lahontan Reservoir was trapped. On an annual basis, however, trapping efficiencies range between 34% and 98%, and are closely related to the total annual discharge. Results also indicate that flow-normalized uf.THg concentrations and loads above and below the reservoir are trending down.

The behavioral response to the putative necromones from dead Tribolium castaneum (Coleoptera: Tenebrionidae) in traps by conspecifics as a function of density and time since capture.

Long-term trapping programs of stored product pests provide information for timely and accurate pest management. Tribolium castaneum (Herbst) (Coleoptera: Tenebrionidae) is a highly successful external-infesting grain pest and is frequently monitored using a commercial pitfall trap that combines pheromonal and kairomonal stimuli. However, an often overlooked component of lure-based traps is the potential for the volatile plume to change over time as individuals are captured. These now-dead insects may then release necromones altering the captures of conspecifics. In this study, we evaluated changes in (i) the behavior of T. castaneum and (ii) the relative change in volatiles over time since dead insects were added and among different densities of dead conspecifics in a commercially available kairomone oil. We used multiple behavior assays, including wind tunnel, release-recapture, and 2-way olfactometer, and performed chemical analyses via headspace collection and gas chromatography coupled with mass spectrometry. Tribolium castaneum response to the kairomone lure was not consistent among assays of density of conspecifics between 4 and 40 adults after 24 or 96 h, or time of seeding over 1-96 h or 8-11 days prior. Tested strains collected in 2012 and 2019 ruled out strain-specific differences. Oil batch effects were also ruled out as a factor contributing to the response of T. castaneum. The relative volatile composition was generally stable among the treatments despite using different seeding densities and seeding times. Given that attraction and relative volatile composition were generally unaffected by prior captures, long-term monitoring programs may be robust in their interpretability over time.

Thiol-based defect healing of WSe2 and WS2

Recent research on two-dimensional (2D) transition metal dichalcogenides (TMDCs) has led to remarkable discoveries of fundamental phenomena and to device applications with technological potential. Large-scale TMDCs grown by chemical vapor deposition (CVD) are now available at continuously improving quality, but native defects and natural degradation in these materials still present significant challenges. Spectral hysteresis in gate-biased photoluminescence (PL) measurements of WSe2 further revealed long-term trapping issues of charge carriers in intrinsic defect states. To address these issues, we apply here a two-step treatment with organic molecules, demonstrating the “healing” of native defects in CVD-grown WSe2 and WS2 by substituting atomic sulfur into chalcogen vacancies. We uncover that the adsorption of thiols provides only partial defect passivation, even for high adsorption quality, and that thiol adsorption is fundamentally limited in eliminating charge traps. However, as soon as the molecular backbone is trimmed and atomic sulfur is released to the crystal, both bonds of the sulfur are recruited to passivate the divalent defect and the semiconductor quality improves drastically. Time-dependent X-ray photoelectron spectroscopy (XPS) is applied here together with other methods for the characterization of defects, their healing, leading energies and occupation. First-principles calculations support a unified picture of the electronic passivation of sulfur-healed WSe2 and WS2. This work provides a simple and efficient method for improving the quality of 2D semiconductors and has the potential to impact device performance even after natural degradation.

Comparison of different traps and attractants in 3 food processing facilities in Greece on the capture of stored product insects.

Certain lures are marketed toward particular pests or classes of pests, while others might be multi-species lures. Investigative aims for this study included both which trap was most sensitive and whether different combinations of traps and attractants were delivering novel information about the stored product insect community. Comparisons were made for all combinations of 3 commercial traps and 4 different attractants plus an untreated control on the capture of stored-product insects for 2 consecutive years in 3 food processing facilities in Central Greece. The traps used in the experiments were Dome Trap (Trécé Inc., USA), Wall Trap (Trécé) and Box Trap (Insects Limited, Ltd., USA). The attractants that were evaluated were 0.13 g of (i) PantryPatrol gel (Insects Limited), (ii) Storgard kairomone food attractant oil (Trécé), (iii) wheat germ (Honeyville, USA), and (iv) Dermestid tablet attractant (Insects Limited). The traps were inspected approximately every 15 days and rotated. A total of 34,000+ individuals were captured belonging to 26 families and at least 48 species. The results indicated that Indian meal moth, Plodia interpunctella (Hübner), red flour beetle, Tribolium castaneum (Herbst), and cigarette beetle, Lasioderma serricorne (F.) were the most abundant. Although there were noticeable differences among the different traps and attractants for specific species, all combinations provided similar information on population dynamics. Generally, Dome traps baited with either the oil or the gel, were found to be the most sensitive. The results of the present study demonstrate the importance of long-term trapping protocols, as a keystone in IPM-based control strategies in food processing facilities.

Evidencing success: Data requirements to model the impacts of long-term management of invasive squirrels

Established widespread populations of invasive vertebrates can be challenging to eradicate and for small to medium-sized vertebrates, such as squirrels, is often not deemed feasible. However, long-term trapping campaigns are necessary to limit spread or reduce impacts. The scale of trapping programmes is often limited by budgets that are not commensurate to the scale of the problem. On-going costs and fundraising are key factors used by decision makers to assess the feasibility of complete removal or long-term management options of established populations. Predicting the time and effort required to successfully manage Invasive Alien Species (IAS) remains a challenge, particularly where different strategies need to be employed across different spatial scales and habitat types, and in response to changing population densities. Statistical methods such as removal models can be applied to quantify population abundance during management operations and could inform planning of resource requirements. However, in practice, the lack of awareness of data requirements results in unsuited or non-standardized data collection. We present data from an invasive grey squirrel (Sciurus carolinensis) management project in the United Kingdom as a case study to illustrate common issues that impact on quantifying project outcomes. We focus on human and operational aspects of implementation and suggest ways of prioritizing analytical requirements. Insights consider conservation targets, data collection and operational design and may be of relevance to stakeholders, analysts, field operators and managers.

All-perfluoropolymer, nonlinear stability-assisted monolithic surface combines topology-specific superwettability with ultradurability

Developing versatile and robust surfaces that mimic the skins of living beings to regulate air/liquid/solid matter is critical for many bioinspired applications. Despite notable achievements, such as in the case of developing robust superhydrophobic surfaces, it remains elusive to realize simultaneously topology-specific superwettability and multipronged durability owing to their inherent tradeoff and the lack of a scalable fabrication method. Here, we present a largely unexplored strategy of preparing an all-perfluoropolymer (Teflon), nonlinear stability-assisted monolithic surface for efficient regulating matters. The key to achieving topology-specific superwettability and multilevel durability is the geometric-material mechanics design coupling superwettability stability and mechanical strength. The versatility of the surface is evidenced by its manufacturing feasibility, multiple-use modes (coating, membrane, and adhesive tape), long-term air trapping in 9-m-deep water, low-fouling droplet transportation, and self-cleaning of nanodirt. We also demonstrate its multilevel durability, including strong substrate adhesion, mechanical robustness, and chemical stability, all of which are needed for real-world applications.

Low-noise and high-power second harmonic generation of 532nm laser for trapping ultracold atoms.

Optical lattices for coherently manipulating ultracold atoms demand high-power, low-noise, narrow-line-width, and continuous-wave lasers. Here, we report the implementation of a 30W 532nm low-noise laser by second harmonic generation from a 1064nm fiber laser, which is capable to generate optical lattices for a quantum gas microscope of Rb87 atoms. The overall conversion efficiency is 59% at an input power of 51W with a lithium triborate crystal coupled to a ring cavity. The relative intensity noise of the output laser is suppressed to -120dBc/Hz in the range of 10Hz-100kHz with a high dynamic range of over 50dB, which is suitable for long-term trapping and coherent manipulation of the quantum gases.

Long-term monitoring reveals the value of continuous trapping to curtail the effects of free-roaming cats in protected island habitats

Free-roaming domestic cats (Felis catus) pose numerous risks to biodiversity conservation, especially in island ecosystems. However, the removal of cats is costly, labor-intensive, and often demands more resources than land managers have at their disposal. These costs might be reduced, however, if trapping effort is regularly scaled to match the prevalence of cats on the landscape rather than consistently exhausting trapping resources even when cats are scarce. Here we analyze the efficacy of a long-term (2014 – 2021) cat removal program which uses motion-activated camera traps to determine monthly trapping effort in the Florida Keys. Furthermore, we compare the trapping effort required for this program against that of a hypothetical removal program with the same resources which does not use surveillance-informed trapping. We hypothesized that cat detections would decline over the study period as a result of the removal program, and that the surveillance-informed approach would require less trapping effort than uninformed trapping would. Our analyses reveal that the sustained, year-round trapping program has reduced the volume and geographic extent of cat detections within the study area. Furthermore, the use of camera traps to inform removal efforts has reduced the number of trap nights required to achieve these goals compared to the hypothetical removal program that did not use surveillance-informed trapping. While climatic and landscape variables also contribute to monthly cat detections, our study reveals that long-term surveillance-informed trapping reduces cat detections without exhausting resources. Such an approach may aid other land managers in their efforts to conserve biodiversity by removing invasive predators.

Migration of carbon atoms in irradiated and non-irradiated alpha-iron studied by magnetic after-effect

Magnetic After-Effect (MAE) and magnetic AC susceptibility studies have been performed on high-purity non-irradiated and Fe-ion irradiated, α-Fe foil samples in the high-temperature range, which became experimentally accessible recently. The pronounced difference in the temperature profile of MAE between non-irradiated and irradiated samples has been identified and ascribed to the trapping of carbon in the irradiated sample into structures that are reluctant to decompose by standard temperature cycling. The accurate background of MAE relaxations at 430 and 610 K in non-irradiated α-Fe samples has been scrutinized by the annealing-type studies in temperature and time domains to conclude that it relies on the formation, decomposition, and mutual transformations of carbide nanoprecipitates nucleated in dislocations, grain boundaries, and in the bcc matrix. Long-term trapping of migrating carbon into carbides and in the 100 nm thick surface layer has also been shown to take place.

Tephritid Fruit Fly Species Composition, Seasonality, and Fruit Infestations in Two Central African Agro-Ecological Zones.

Bactrocera dorsalis and several Africa-native Ceratitis species are serious constraints to fruit production in sub-Saharan Africa. A long-term trapping and fruit collection study was conducted (2011-2016) in two contrasting agro-ecological zones (AEZs) of Cameroon to determine fruit fly species composition, seasonality, attraction to various lures and baits, and fruit infestation levels. Ten tephritid species from genera Bactrocera, Ceratitis, Dacus, and Perilampsis were captured in traps. Bactrocera dorsalis was the most dominant of the trapped species and persisted throughout the year, with peak populations in May-June. Ceratitis spp. were less abundant than B. dorsalis, with Ceratitis anonae dominating in the western highland zone and Ceratitis cosyra in the humid forest zone. Methyl eugenol and terpinyl acetate captured more B. dorsalis and Ceratitis spp., respectively than Torula yeast. The latter was the most effective food bait on all tephritid species compared with BioLure and Mazoferm. Bactrocera dorsalis was the dominant species emerging from incubated fruits, particularly mango, guava, and wild mango. Four plant species-I. wombolu, Dacryodes edulis, Voacanga Africana and Trichoscypha abut-were new host records for B. dorsalis. This study is the first long-duration and comprehensive assessment of frugivorous tephritid species composition, fruit infestations, and seasonality in Central Africa.

Phosphate-Trapping Liposomes for Long-Term Management of Hyperphosphatemia.

Hyperphosphatemia is a typical complication of end-stage renal disease, characterized by elevated and life-threatening serum phosphate levels. Hemodialysis does not enable sufficient clearance of phosphate, due to slow cell-to-plasma kinetics of phosphate ions; moreover, dietary restrictions and conventional treatment with oral phosphate binders have low success rates, together with adverse effects. Here, we developed a new concept of phosphate-trapping liposomes, to improve and prolong the control over serum phosphate levels. We designed liposomes modified with polyethylene glycol and encapsulated with the phosphate binder ferric citrate (FC liposomes). These liposomes were found to trap phosphate ions in their inner core, and thereby lower free phosphate ion concentrations in solution and in serum. The FC liposomes showed higher phosphate binding ability as phosphate concentrations increased. Moreover, these liposomes showed a time-dependent increase in uptake of phosphate, up to 25 h in serum. Thus, our findings demonstrate effective long-term phosphate trapping by FC liposomes, indicating their potential to reduce serum phosphate toxicity and improve current management of hyperphosphatemia.

Windborne migration amplifies insect-mediated pollination services.

Worldwide, hoverflies (Syrphidae: Diptera) provide crucial ecosystem services such as pollination and biological pest control. Although many hoverfly species exhibit migratory behavior, the spatiotemporal facets of these movement dynamics, and their ecosystem services implications are poorly understood. In this study, we use long-term (16-year) trapping records, trajectory analysis, and intrinsic (i.e., isotope, genetic, pollen) markers to describe migration patterns of the hoverfly Episyrphus balteatus in northern China. Our work reveals how E. balteatus migrate northward during spring-summer and exhibits return (long-range) migration during autumn. The extensive genetic mixing and high genetic diversity of E. balteatus populations underscore its adaptive capacity to environmental disturbances, for example, climate change. Pollen markers and molecular gut analysis further illuminate how E. balteatus visits min. 1012 flowering plant species (39 orders) over space and time. By thus delineating E. balteatus transregional movements and pollination networks, we advance our understanding of its migration ecology and facilitate the design of targeted strategies to conserve and enhance its ecosystem services.

Numerical Simulations of Carbon Dioxide Storage in Selected Geological Structures in North-Western Poland

In this study, dynamic simulation models of CO2 injection into saline aquifers of the Choszczno-Suliszewo structure located in north-western Poland were constructed for two scenarios with different injection rates. The injection rates of 1 Mt CO2/year and 2 Mt CO2/year were analysed for each of the injection wells. Changes in pressures, characteristic for the sequestration process, were analysed; in addition, the spatial distribution of free CO2 saturation in the structure and carbon dioxide dissolved in brine were presented in a graphical form. The observation time of changes occurring in the rock mass in the interval of up to 1,000 years after the completion of injection was assumed. During the modelling of CO2 sequestration in Lower Jurassic aquifers in the Suliszewo model, the previously assumed CO2 injection rates were achieved for both injection scenarios. The observed pressure increase does not pose any threat to the Suliszewo structure tightness. The sequestration process was found to be highly effective due to the phenomenon of the dissolution of CO2 in brine and the resulting convection motion of brine enriched with carbon dioxide. Consequently, there is an increase in CO2 storage capacity and permanent long-term trapping of the injected carbon dioxide. The process of the displacement of injected CO2 from the collector layers to the layers constituting the reservoir sealing was observed. This phenomenon takes place in the upper parts of the Choszczno structure and is caused mainly by the locally occurring worse technical parameters of seal layers in this area.

Interface topology and evolution of particle patterns on deformable drops in turbulence

The capture of neutrally buoyant, sub-Kolmogorov particles at the interface of deformable drops in turbulent flow and the subsequent evolution of particle surface distribution are investigated. Direct numerical simulation of turbulence, phase-field modelling of the drop interface dynamics and Lagrangian particle tracking are used. Particle distribution is obtained considering excluded-volume interactions, i.e. by enforcing particle collisions. Particles are initially dispersed in the carrier flow and are driven in time towards the surface of the drops by jet-like turbulent fluid motions. Once captured by the interfacial forces, particles disperse on the surface. Excluded-volume interactions bring particles into long-term trapping regions where the average surface velocity divergence sampled by the particles is zero. These regions correlate well with portions of the interface characterized by higher-than-mean curvature, indicating that modifications of the surface tension induced by the presence of very small particles will be stronger in the highly convex regions of the interface.