Argyroneta Research Articles

Bio-inspired 3D printing of strain-hardening cementitious composites reticulated shell roofs

Inspired by the diving bell structure of the water spider, this study presents an innovative 3D printed strain-hardening cementitious composite (3DP-SHCC) reticulated shell roof. The compressive behavior of the 3DP-SHCC reticulated shell roof is evaluated using a combination of experimental tests and numerical simulation approaches. The 3DP-SHCC reticulated shell roof features excellent mechanical properties and an aesthetically pleasing appearance. The specific energy absorption and ductility index of this structure are 0.065 J/g and 0.078, respectively. The feasibility of this concept is validated by constructing a complete building structure within just 16 min. This printing process has the potential to create complex designs with minimal labor, making it suitable for rapid construction in extreme environments.

3D printed strain-hardening cementitious composites (3DP-SHCC) reticulated shell roof inspired by the water spider

Inspired by the diving bell of the water spider, this paper designs and fabricates nature-inspired 3D printed strain-hardening cementitious composites (3DP-SHCC) reticulated shell roofs. The compression performance and energy absorption capabilities of 24 specimens with eight different strut angles are evaluated through a combined experimental and simulation approach. The results demonstrate that all specimens exhibit excellent ductility and structural integrity under ultimate load conditions. The 45–45 and 60–60 specimens exhibit the highest energy absorption and efficiency, respectively, while 60–90 specimens exhibit the best ductility. Compared with traditional lightweight concrete structures, reticulated shells have lower average structural density, higher specific energy absorption, and ductility index values. A building with a proposed nature-inspired 3DP-SHCC reticulated shell roof is constructed to verify buildability, demonstrating reduced construction time and enhanced automation. This paper offers valuable insights for highly automated construction projects, especially in extreme environments.

On-Demand Transport Bubbles Adhering to Noncontiguous Patterned Superhydrophobic Surfaces Using a Superhydrophobic Tweezer.

Bubble transportation and related flotation are ubiquitous phenomena in nature and industry. Various surfaces with distinct morphologies and specific wettability properties have been engineered by organisms in nature and by humans to facilitate the targeted movement of bubbles. However, existing methods predominantly rely on continuous surfaces, limiting the ability of bubbles to deviate from their path before reaching their intended destination. Therefore, directional transportation of bubbles using noncontiguous surfaces still remains a significant challenge. Inspired by water spiders' ability to capture bubbles underwater using their hydrophobic surface for survival, we propose a novel transport strategy that utilizes patterned superhydrophobic surfaces (PSHSs) and a superhydrophobic tweezer. This strategy is implemented by switching between the hood mode and puncture mode of the moving three-phase contact lines to load and unload the bubble. To quantitatively evaluate the loss ratio of the bubble during transportation, a simple and exquisite bubble-weighing apparatus is devised. Our findings indicate that circular PSHSs demonstrate superior bubble adhesion and achieve the highest bubble transport ratio of 95.1%. In order to validate the promising application of this novel method, we employ the computer numerical control (CNC) technology to facilitate the autonomous loading and precise transportation of underwater bubbles, as well as the blending and ionization of combustible gas bubbles with air bubbles at different volume ratios.

Ultrastructure of silk threads of the water spider Argyroneta aquatica (Clerck, 1757) (Araneae, Cybeidae) in comparison with that of some mites

Silk of the water spider Argyroneta aquatica (Clerck, 1757) was obtained in the laboratory in the form of a capturing web irrespective of the formation of a diving bell and egg cocoon. Silk threads were examined by light microscopy, scanning (SEM), and transmission electron microscopy (TEM) as well as by atomic force (AFM) microscopy. Based on the diameter and internal organization, the silk threads have been divided into five types—a-, b-, c-, d-, and e-types interlaced freely in the thread bundles taken for examinations. Threads of all types are infinitely long, non-branched, round in shape, uniform in width through their course, and rarely found to be ruptured. Threads of the a-type are mostly straight, up to 1,000 nm in diameter, and composed of a fibrillary wall enveloping an electron-dense vacuolated core, which may be occasionally absent. The wall may also become lost, leaving a single core substance surrounded by a slightly wrinkled double membrane. Threads of the b-, c-, and d-types are organized nearly identical, being composed of a fine granular electron-light uniform material enveloped by a fine membrane. The diameter of these threads varies from max. 500 nm in the b-type and 120 nm in the c-type to around 50 nm in the d-type. Threads of these types are more convoluted and more numerous than threads of the a-type. Threads of the last kind, the e-type, occur rarely and are significantly larger with a diameter of around 3.5–4.5 µm. They possess the layered membranous wall surrounding a uniformly dense core. The silk of the water mites Limnochares aquatica (L., 1758) and Limnesia maculata (O.F. Müller, 1776) is composed of threads of only one type that closely corresponded to the a-type threads of A. aquatica. Conversely, the silk of the two-spotted spider mite Tetranychus urticae (C.L. Koch, 1836) consists of threads highly correlated with the d-type threads of A. aquatica. This finding shows that in different phylogenetic lineages of arachnids, the mechanisms of silk production are quite similar.

On the mechanical stability of the air volume trapped within the diving bell of the water spider Argyroneta aquatica (Araneae;Cybaeidae); a thermodynamic analysis based on a model

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Attachment discs of the diving bell spider Argyroneta aquatica

To adhere their silk threads for the construction of webs and to fix the dragline, spiders produce attachment discs of piriform silk. Uniquely, the aquatic spider Argyroneta aquatica spends its entire life cycle underwater. Therefore, it has to glue its attachment discs to substrates underwater. Here we show that Argyroneta aquatica applies its thread anchors within an air layer around the spinnerets maintained by superhydrophobic setae. During spinning, symmetric movements of the spinnerets ensure retaining air in the contact area. The flat structure of the attachment discs is thought to facilitate fast curing of the piriform adhesive cement and improves the resistance against drag forces. Pull-off tests on draglines connected with attachment discs on different hydrophilic substrates point to dragline rupture as the failure mode. The Young´s modulus of the dragline (8.3 GPa) is within the range as in terrestrial spiders. The shown structural and behavioral adaptations can be the model for new artificial underwater gluing devices.

Effect of predators on Anopheles arabiensis and Anopheles funestus larval survivorship in Homa Bay County Western Kenya

BackgroundThe rise of insecticide resistance against malaria vectors in sub-Saharan Africa has resulted in the need to consider other methods of vector control. The potential use of biological methods, including larvivorous fish, Bacillus thuringiensis israelensis (Bti) and plant shading, is sustainable and environmentally friendly options. This study examined the survivorship of Anopheles arabiensis and Anopheles funestus larvae and habitat productivity in four permanent habitat types in Homa Bay county, western Kenya.MethodsPredator densities were studied in a laboratory setup while habitat productivity and larval survivorship was studied in field setup.ResultsFish were observed as the most efficient predator (75.8% larval reduction rate) followed by water boatman (69%), and dragonfly nymph (69.5%) in predation rates. Lower predation rates were observed in backswimmers (31%), water beetles (14.9%), water spiders (12.2%), mayflies (7.3%), and tadpoles (6.9%). Increase in predator density in the field setup resulted in decreased Culex larval density. Larval and pupa age–specific distribution was determined and their survivorship curves constructed. Combined larvae (Stage I–IV) to pupa mortality was over 97% for An. arabiensis and 100% for An. funestus. The highest larval stage survival rate was from larval stages I to II and the lowest from larval stage IV to pupa. Stage-specific life tables indicated high mortality rates at every developmental stage, especially at the larval stage II and III.ConclusionDetermination of the efficiency of various larval predators and habitat productivity will help with the correct identification of productive habitats and selection of complementary vector control methods through environmental management and/or predator introduction (for instance fish) in the habitats.

A Sun that Never Sets: Eastern Cherokee Tattoo Artist John Henry Gloyne and the Aesthetics of Reimagining

Abstract: This article examines a selection of work by contemporary tattoo artist John Henry Gloyne (Eastern Band of Cherokee Indians) to understand how tattooing functions as an Indigenous creative practice that can imagine alternative realities and reestablish connections to Native pasts and presents. Gloyne's work redefines contemporary Native tattooing by highlighting its continuing significance and artistic innovations in the present. In doing so, Gloyne's work challenges the settler notion that Native cultural practices are static and stuck in the past. The authors' analysis includes Gloyne's reinvention of Cherokee symbols (water spider and Booger mask tattoos), early/mid-twentieth-century Americana tattoo flash, and his tattoo-inspired painting Sacred Realms: Tobacco Offerings to the Picture Machine . Honma and Francoso employ an analytic of "reimagining" to investigate how Gloyne's work embraces an ethos of experimentation and innovation that moves beyond settler frameworks of comprehension. In order to understand how he challenges various modes of representation and ways of looking that normalize the settler project, they historicize the symbols and motifs found in Gloyne's work. They incorporate interdisciplinary methods of visual analysis, historical recontextualization, and interview data to center Gloyne's unique aesthetic approach, which foregrounds renewed ways of envisioning and embodying Indigenous worlds.

Зообентос русла реки Северная Двина

The Northern Branch of All-Russian Research Institute of Fisheries and Oceanography (FSBNU VNIRO) began comprehensive research on zoobenthos in the mainstream of the Severnaya Dvina River in 1995. Systematic studies of zoobenthos at the Severnaya Dvina River for the first time made it possible to obtain the most complete information about the taxonomic composition of the invertebrates, the number and frequency of taxons across different sections of the mainstream, the number and biomass of each taxon. As part of the zoobenthos for the entire study period (1995–2019), 20 taxons belonging to 6 types and 8 invertebrates classes were discovered. The average number of invertebrates taxons found in samples for the entire study period was 9 in the upper and middle parts of the mainstream of the Severnaya Dvina River, 8 in the lower parts, varying in significant ranges from 2 to 15 in different years. Every year at all stations in the samples there were oligochaetes and larvae of chironomids (or lake flies), which dominated in frequency. The lowest frequency of occurrence (5.3% each) was found in the upper part of the mainstream of the Severnaya Dvina river for the larvaes of stoneflies and springtail, in the middle parts – 5.6% for gastropods, leeches, water bugs, beetle larvaes and turbellarians. In the lower part of the mainstream of the Severnaya Dvina water spiders, water bugs and beetle larvae were rarely found in samples (5.3% each). The number of invertebrates in the mainstream of the Severnaya Dvina River varied within very wide limits, averaging 3052 units/m2 for the entire observation period. The average biomass of invertebrates in the mainstream of the Severnaya Dvina rive amounted to 2.35 g/m2. The biomass base was also formed by oligochaetes and larvaes of chironomids. Obviously, interannual changes in the number and biomass of zoobenthos and changes in these parameters along the length of the river are more associated with the hydrological features of each year of observations in the Severnaya Dvina River and its largest tributaries than with the influence of human activity. Clarification of the relationship of hydrological parameters, and above all – the water content of the river year to year requires additional research.

Water Spider-Inspired Nanofiber Coating with Sustainable Scale Repellency via Air-Replenishing Strategy.

To survive underwater even in severely hypoxic water for a long period, thewater spider has to periodically collect and replenish air into the diving bell. Inspired by this natural air-replenishing strategy, a water spider-inspired nanofiber (WSN) coating with underwater superaerophilicity displaying excellent and sustainable scalephobic capability is prepared. Air film on the WSN coating can be well-kept and further employed as the barrier layer for scale repellence. Significantly, scalephobic capability of the WSN coating mainly originates from two aspects: inhibiting interfacial nucleation and reducing interfacial adhesion of scale. Compared with previous studies, this WSN coating achieves excellent and sustainable scale repellence (≈ 98% reduction in scale deposition) even after a one-month dynamic scaling test. Thus, this air-replenishing strategy may raise a new avenue for advanced long-term scalephobic materials.

Supermarket and Water Spider Concept for Improving Door Sub-Assembly Productivity

This research is based on a case study at the door sub-assembly area of a German car manufacturer in Indonesia. The door sub-assembly area is responsible for assembling doors to be supplied to the specific station in assembly line that will assemble the finished doors to the car. The area had a problem in supplying the doors to the main assembly line on time. This means, the cycle time of door sub-assembly is higher than that of the assembly line. After observation, the factor that greatly contributes to the high cycle time can be identified, which is motion waste. Therefore, a unique approach is offered to overcome the situation, which involves re-designing work system and work area. The approach is to implement new working system by adopting lean tool water spider to significantly reduce motion waste. In the end, the initial and after condition will be contrasted to see the improvement made by this research. The results of this study could give the company several benefits: improved working efficiency of workers, reduced cycle time in door assembly and reduced fatigue of workers.

Internet of Things‐based root disease classification in alfalfa plants using hybrid optimization‐enabled deep convolutional neural network

SummaryIn this article, water cycle spider monkey optimization‐based deep convolutional neural network (WCSMO‐based deep CNN) is designed to classify root diseases in alfalfa plants. In the proposed method, the alfalfa plant root images are accessed remotely using a camera and transferred to the sink node to classify the disease. The proposed water cycle spider monkey optimization (WCSMO) algorithm performs the routing. Once the root images are received at base station or sink node, the images undergo preprocessing, segmentation, and classification. In the preprocessing module, a median filter is utilized to reduce the image noise. The preprocessed output is subjected to the segmentation phase, which is carried out using enhanced fuzzy C‐means clustering. The segmented results are passed to the classification step, where the deep convolutional neural network (deep CNN) is employed to categorize the root illness after being trained by the proposed WCSMO algorithm, which combines the water cycle algorithm and spider monkey optimization. The developed method achieved effective performance in terms of the metrics like sensitivity, accuracy, and specificity with the value of 0.9169, 0.9198, and 0.92. Moreover, the proposed WCSMO algorithm obtained the average energy and average throughput of 0.26641 J, and 91.483%, respectively.

Nature-inspired trapped air cushion surfaces for environmentally sustainable antibiofouling

Feathers of seabirds and waterfowl (for example the mallard duck (Anas platyrhynchos)) consist of hierarchical fibrillar structures encapsulated with hydrophobic preen oil. These characteristics afford waterproofing through the entrapment of air pockets, enabling swimming and diving for such bird species. This liquid repellency mechanism for bird feathers is mimicked by surface hydrophobisation of fibrous nonwoven polypropylene textiles to create large volumes of trapped air at the solid–liquid interface (plastron). Higher static water contact angle values correlate to a greater resistance towards water ingress (akin to the behaviour of mallard feathers). In order to extend the trapped gas layer lifetimes, the transportation of air from the water surface to a submerged air bubble by the diving bell spider (Argyroneta aquatica) for respiration is mimicked via short duration (< 1 s) solar-powered air bubble bursts once every 2 h. This combination of ornithological and arachnological inspired approaches yields stable trapped gas layers at the solid–liquid interface which are shown to inhibit biofouling in real-world outdoor wet environments.

Hydroecology of Argyroneta aquatica’s Habitat in Hantangang River Geopark, South Korea

The water spider (Argyroneta aquatic) is the only known spider to live a fully aquatic life. Therefore, it has been the subject of a series of studies on various aspects of its unique biology such as its reproductive behavior, sexual dimorphism, physiology, genetics, and silk. However, there have been relatively few studies on the hydroecology of where water spiders live. The water spider habitat in Eundae-ri, Yeoncheon is the only habitat for A. aquatica, a globally rare species, in South Korea. In this region, the water level of the wetland is automatically adjusted to groundwater owing to continued drying. Here, the surface water, wetland, and groundwater near the A. aquatica habitat were studied using hydrochemical, microbiological, and correlation analyses. The hydrochemical properties—water temperature, pH, electrical conductivity, dissolved oxygen (DO), oxidation reduction potential, and turbidity—of the surface water and wetland were similar. The Piper diagrams revealed that the wetlands, surface water, and most of the groundwater portrayed Ca-HCO3-type properties, whereas only areas where the water level of the wetland was controlled displayed Na-HCO3-type properties. Furthermore, the NO3 content was too low to be detected in the wetland, indicating clean and non-polluted water conditions; additionally, heavier oxygen-hydrogen isotopes were observed because these regions were climatically affected by the wetland. The dominant bacteria were Proteobacteria, Actinobacteria, Bacteroidetes, Cyanobacteria, Verrucomicrobia, and Nitrospirae. The correlation analysis revealed that the major environmental control factors of the A. aquatica habitat were DO, temperature, and pH, and the related bacteria were Cyanobacteria, Actinobacteria, and Verrucomicrobia.

LES-Predicted Flow Patterning in a Newly-Designed Reference Test Sample with Relevance to IC Engine-Related Cooling Channels

&lt;div class="section abstract"&gt;&lt;div class="htmlview paragraph"&gt;A test sample configuration with a circular cross-section has been conceptualized to reproduce all geometrically relevant flow-guided elements - straight segments, deflections, bifurcations, impingement regions, confluence - as they can also be found in the cooling systems of realistic Internal Combustion (IC) engines. This newly-designed reference test sample is termed as Water Spider Geometry (WSG), with the shape inspired by the flow guidance around an IC engine cylinder head. Computational investigations are carried out within the framework of a BMWi (German Federal Ministry for Economic Affairs and Energy) project by applying a well-resolved, highly comprehensive Large Eddy Simulation aiming at providing a meaningful assessment of the isothermal flow topology within the WSG. The basis forms a fully-hexahedral, block-structured grid arrangement comprising 290 million cells with the results considered to be a reference solution for further investigations.&lt;/div&gt;&lt;/div&gt;

OPTIMISATION OF MILKRUN ROUTES IN MANUFACTURING SYSTEMS IN THE AUTOMOTIVE INDUSTRY

The in-plant supply has a great impact on the performance of manufacturing operation, because the manufacturing-related logistics operations influence the efficiency of manufacturing. There are different solutions to perform in-plant supply, in the automotive industry the milkrun and water spider solutions are widely used. Within the frame of this article the authors describe the optimization of milkrun routes in the manufacturing plant of an automotive supplier. The described methodology simplifies the problem for single- and multi-milkrun problems and the solution is demonstrated with an Excel Solver-based methodology. The optimization process and its practicability will be demonstrated through an example.

Argyroneta aquatica

This datasheet on Argyroneta aquatica covers Identity, Distribution.

Rare and poorly known spider species of the Volhynian Polissia (Ukraine)

State of knowledge about spiders (Arachnida: Araneae) from the Volhynian Polissia, which is located within the Volyn and Rivne oblasts of Ukraine, were analyzed. According to the literature-derived data, araneofauna of this region consists of 285 species. More than 250 of them were listed from the Shatsk National Nature Park of the Volyn oblast and 75 from Lva-Stvyga inter-river area of the Rivne oblast. These studies cover the extreme western and eastern points of the region, while the main part of the territory remains unexplored. Based on the analysis of published data and in accordance with unpublished material of my own collection, six rare and poorly-known species of spiders of the Volhynian Polissia were singled out, namely Argyroneta aquatica (Clerck, 1757), Lathys heterophthalma Kulczyński, 1891, Gnaphosa nigerrima L. Koch, 1877, Micaria micans (Blackwall, 1858), Zelotes exiguus (Müller &amp; Schenkel, 1895) та Erigonoplus foveatus (Dahl, 1912). Among them, Lathys heterophthalma is first mentioned from Ukrainian Polissia, Micaria micans – from Ukraine. For each of species, a brief description of the distribution in the world and in Ukraine, as well as environmental preferences are given, localities within the Volhynian Polissia are described and highlighted on the map. Analysing these data, we can assume that the number of records of species such as Argyroneta aquatica, Erigonoplus foveatus and Zelotes exiguus will certainly increase when the territory of Polissia is more fully covered by research. Two species, Lathys heterophthalma and Micaria micans, are known from single localities. However, Micaria micans as a separate species is considered only from 2020. Therefore, it is necessary to revise the available material of Micaria pulicaria, which was previously considered a senior synonym to Micaria micans, and to accumulate new data on the distribution of those two species not only in Ukraine but also in Europa. Gnaphosa nigerrima, requires monitoring of populations because it occurs in oligotrophic sphagnum bogs, the area of which has been steadily declining in recent decades. From this point of view, it should be included in the list of rare species of animals in the region.

Predatory and competitive interaction in Anopheles gambiae sensu lato larval breeding habitats in selected villages of central Uganda

BackgroundMalaria is often persistent in communities surrounded by mosquito breeding habitats. Anopheles gambiae sensu lato exploit a variety of aquatic habitats, but the biotic determinants of its preferences are poorly understood. This study aimed to identify and quantify macroinvertebrates in different habitat types with determined water physico-chemical parameters to establish those preferred by An. gambiae s.l. larvae as well as their predators and competitors.MethodsA field survey was conducted in Kibuye and Kayonjo villages located in the vicinity of the River Sezibwa, north-eastern Uganda to identify Anopheline larval habitats shared by aquatic insects. Habitats were geo-recorded and as streams, ponds, temporary pools and roadside ditches. From October to December 2017, random microhabitats/quadrats were selected from each habitat type, their water physico-chemical parameters (electrical conductivity, total dissolved solids, temperature and pH) were measured, and they were sampled for macroinvertebrates using standard dippers. All collected arthropod macroinvertebrates were then morphologically identified to family level and enumerated.ResultsPrincipal component analysis showed that the four larval habitat types were characterized by distinct physico-chemical parameter profiles. Ponds and streams had the highest number and diversity of macroinvertebrate insect taxa and sustained few An. gambiae s.l. larvae. Anopheles gambiae s.l. were more common in roadside ditches and particularly abundant in temporary pools which it commonly shared with Dytiscidae (predaceous diving beetles) and Culex spp. Cluster correlation analysis conducted on the abundance of these taxa within quadrats suggested that An. gambiae s.l. and Dytiscidae have the most similar patterns of microhabitat use, followed by Cybaeidae (water spiders). Whilst Culex spp. co-occurred with An. gambiae s.l. in some habitats, there was only partial niche overlap and no clear evidence of competition between the two mosquito taxa.ConclusionsPonds and streams are habitats that host the largest diversity and abundance of aquatic insect taxa. Anopheles gambiae s.l. larvae distinctively preferred temporary pools and roadside ditches, where they were exposed to few predators and no apparent competition by Culex spp. Further studies should aim to test the impact of Dytiscidae and Cybaeidae on An. gambiae s.l. dynamics experimentally.Graphical

Relationships between characteristics of macrobenthic assemblages and environmental variables in the Heihe River Basin, China

Abstract To clarify the characteristics of macrobenthic assemblages and their response to the aquatic environment in the upper and middle reaches of the Heihe River, water quality, sediments and macrobenthos measurements were conducted in the summers of 2018 and 2019. The results showed that 50 species of macrobenthos were identified, belonging to 3 phyla, 7 classes, 15 orders and 32 families, mainly arthropods (37 species) and mollusks (11 species). Argyroneta aquatica, Chlaznius sp., dragonfly nymphs, Palaemon modestus, Radix auricularia, Cyraulus albus and Suecinea sp. were the dominant species in the whole study region; most of these are pollution-tolerant and moderately pollution-tolerant species. The macrobenthos density and biomass ranged from 10 to 577 ind./m2 and from 0.0907 to 50.0562 g/m2, respectively, showing high spatial heterogeneity. Predators were the main functional feeding group. One-way analysis of variance clarified that Margalef's index and the Shannon–Wiener index differed significantly among the spatial areas (P &amp;lt; 0.05). Canonical correspondence analysis showed that the spatial heterogeneity of the macrobenthos was affected by the water temperature and the total nitrogen and total phosphorus in sediments (P &amp;lt; 0.05).