Journal articles on the topic 'Local Artificial Substrate'
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Bietti, S., C. Somaschini, N. Koguchi, C. Frigeri, and S. Sanguinetti. "Self-Assembled Local Artificial Substrates of GaAs on Si Substrate." Nanoscale Research Letters 5, no. 12 (August 31, 2010): 1905–7. http://dx.doi.org/10.1007/s11671-010-9760-5.
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Li, L., A. J. Fijneman, J. A. Kaandorp, J. Aizenberg, and W. L. Noorduin. "Directed nucleation and growth by balancing local supersaturation and substrate/nucleus lattice mismatch." Proceedings of the National Academy of Sciences 115, no. 14 (March 19, 2018): 3575–80. http://dx.doi.org/10.1073/pnas.1712911115.
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Controlling nucleation and growth is crucial in biological and artificial mineralization and self-assembly processes. The nucleation barrier is determined by the chemistry of the interfaces at which crystallization occurs and local supersaturation. Although chemically tailored substrates and lattice mismatches are routinely used to modify energy landscape at the substrate/nucleus interface and thereby steer heterogeneous nucleation, strategies to combine this with control over local supersaturations have remained virtually unexplored. Here we demonstrate simultaneous control over both parameters to direct the positioning and growth direction of mineralizing compounds on preselected polymorphic substrates. We exploit the polymorphic nature of calcium carbonate (CaCO3) to locally manipulate the carbonate concentration and lattice mismatch between the nucleus and substrate, such that barium carbonate (BaCO3) and strontium carbonate (SrCO3) nucleate only on specific CaCO3 polymorphs. Based on this approach we position different materials and shapes on predetermined CaCO3 polymorphs in sequential steps, and guide the growth direction using locally created supersaturations. These results shed light on nature’s remarkable mineralization capabilities and outline fabrication strategies for advanced materials, such as ceramics, photonic structures, and semiconductors.
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Kwak, Jun-Hyuk, Youngdo Jung, Kyungjun Song, and Shin Hur. "Fabrication of Si3N4-Based Artificial Basilar Membrane with ZnO Nanopillar Using MEMS Process." Journal of Sensors 2017 (2017): 1–11. http://dx.doi.org/10.1155/2017/1308217.
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This paper presents the fabrication of Si3N4-based artificial basilar membrane (ABM) with ZnO nanopillar array. Structure of ABMs is composed of the logarithmically varying membrane fabricated by MEMS process and piezonanopillar array grown on the Si3N4-based membrane by hydrothermal method. We fabricate the bottom substrate containing Si3N4-based membrane for inducing the resonant motions from the sound wave and the top substrates of electrodes for acquiring electric signals. In addition, the bonding process of the top and bottom substrate is performed to build ABM device. Depending on sound wave input of the specific frequency, specific location of the ABM produces a resonant behavior. Then a local deformation of the piezonanopillar array produces an electric signal between top and bottom electrode. As experimental results of the fabricated ABM, the measured resonant frequencies are 2.34 kHz, 3.97 kHz, and 8.80 kHz and the produced electrical voltages on each resonant frequency are 794 nV, 398 nV, and 89 nV. Thus, this fabricated ABM device shows the possibility of being a biomimetic acoustic device.
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Hernández-Arana, Héctor A., and Brenda Ameneyro-Angeles. "Benthic biodiversity changes due to the opening of an artificial channel in a tropical coastal lagoon (Mexican Caribbean)." Journal of the Marine Biological Association of the United Kingdom 91, no. 5 (December 23, 2010): 969–78. http://dx.doi.org/10.1017/s0025315410002043.
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The construction of an artificial channel to a small embayment in the Chetumal Bay coastal lagoon complex, located on the Caribbean coast of Mexico, provided an opportunity to evaluate how large environmental changes influenced the structure of a low diversity benthic system. The objective of this study was to demonstrate that despite the absence of previous baseline information, the artificial channel has induced measurable changes in the biodiversity patterns of a hard substrata benthic community. The experimental design took into account the environmental setting influencing local benthic community structure and the sources of variability as a result of different substrate types and water depth. Four localities with ten replicates each were surveyed, and the presence/absence of macrobenthic biota species recorded during the rainy season. Our analysis using permutational multivariate analysis of variance indicated a significant increase in species richness in locations adjacent to the artificial channel. The highest species richness (66 species) was observed in the immediate area adjacent to the artificial channel and where exclusive species density was three to six times (18 exclusive species) than those present in other localities (6, 5 and 3 species) away from the channel. The presence of six species of hard corals indicated that the artificial channel offers a more suitable habitat for marine organisms colonizing the area than the natural channel. This study indicates the relative significance of confinement in structuring coastal lagoon benthic assemblages in tropical systems. Our results are similar to other findings underscoring the rate of colonization of marine organisms as a relevant process to explain benthic assemblage gradients and the importance of spatial–temporal interactions. The changes in species diversity caused by the artificial channel were clearly identified based on a sampling design that incorporated the main sources of environmental variability (distance to channels, substrate type and depth). Our study further demonstrates that changes in benthic community structure in the Chetumal Bay lagoon complex, as a result of human impacts, can be assessed even when community structure data before impact are absent.
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Biber, P., S. Seifert, M. K. Zaplata, W. Schaaf, H. Pretzsch, and A. Fischer. "Relationships between substrate, surface characteristics, and vegetation in an initial ecosystem." Biogeosciences 10, no. 12 (December 16, 2013): 8283–303. http://dx.doi.org/10.5194/bg-10-8283-2013.
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Abstract. We investigated surface and vegetation dynamics in the artificial initial ecosystem "Chicken Creek" (Lusatia, Germany) in the years 2006–2011 across a wide spectrum of empirical data. We scrutinized three overarching hypotheses concerning (1) the relations between initial geomorphological and substrate characteristics with surface structure and terrain properties, (2) the effects of the latter on the occurrence of grouped plant species, and (3) vegetation density effects on terrain surface change. Our data comprise and conflate annual vegetation monitoring results, biennial terrestrial laser scans (starting in 2008), annual groundwater levels, and initially measured soil characteristics. The empirical evidence mostly confirms the hypotheses, revealing statistically significant relations for several goal variables: (1) the surface structure properties, local rill density, local relief energy and terrain surface height change; (2) the cover of different plant groups (annual, herbaceous, grass-like, woody, Fabaceae), and local vegetation height; and (3) terrain surface height change showed significant time-dependent relations with a variable that proxies local plant biomass. Additionally, period specific effects (like a calendar-year optimum effect for the occurrence of Fabaceae) were proven. Further and beyond the hypotheses, our findings on the spatiotemporal dynamics during the system's early development grasp processes which generally mark the transition from a geo-hydro-system towards a bio-geo-hydro system (weakening geomorphology effects on substrate surface dynamics, while vegetation effects intensify with time), where pure geomorphology or substrate feedbacks are changing into vegetation–substrate feedback processes.
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Grace, Robert A. "The Factors and Processes that Influence Artificial Reef Longevity." Marine Technology Society Journal 35, no. 2 (June 1, 2001): 3–13. http://dx.doi.org/10.4031/002533201788001910.
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Demolition products, surplus articles, and designed structures may be placed on the sea floor as habitat for fish and invertebrates or to provide substrate for corals or large attached plants. Such installations should be stable in the long-term, not to be torn apart or swept away during episodes of severe local storms or the onslaught of large swell from distant disturbances. To this end, calculations must be carried out, for a "design wave" deemed appropriate for the site involved, to evaluate applied kinematical loads and seabed reactions. Should the artificial reef appear unstable, then it must be pinned to the bottom unless meaningful redesign is feasible. This paper discusses the various aspects of the whole stability question and provides well more than one hundred pertinent and timely references.
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Remuzzi, Andrea, Barbara Bonandrini, Matteo Tironi, Lorena Longaretti, Marina Figliuzzi, Sara Conti, Tommaso Zandrini, Roberto Osellame, Giulio Cerullo, and Manuela Teresa Raimondi. "Effect of the 3D Artificial Nichoid on the Morphology and Mechanobiological Response of Mesenchymal Stem Cells Cultured In Vitro." Cells 9, no. 8 (August 11, 2020): 1873. http://dx.doi.org/10.3390/cells9081873.
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Stem cell fate and behavior are affected by the bidirectional communication of cells and their local microenvironment (the stem cell niche), which includes biochemical cues, as well as physical and mechanical factors. Stem cells are normally cultured in conventional two-dimensional monolayer, with a mechanical environment very different from the physiological one. Here, we compare culture of rat mesenchymal stem cells on flat culture supports and in the “Nichoid”, an innovative three-dimensional substrate micro-engineered to recapitulate the architecture of the physiological niche in vitro. Two versions of the culture substrates Nichoid (single-layered or “2D Nichoid” and multi-layered or “3D Nichoid”) were fabricated via two-photon laser polymerization in a biocompatible hybrid organic-inorganic photoresist (SZ2080). Mesenchymal stem cells, isolated from rat bone marrow, were seeded on flat substrates and on 2D and 3D Nichoid substrates and maintained in culture up to 2 weeks. During cell culture, we evaluated cell morphology, proliferation, cell motility and the expression of a panel of 89 mesenchymal stem cells’ specific genes, as well as intracellular structures organization. Our results show that mesenchymal stem cells adhered and grew in the 3D Nichoid with a comparable proliferation rate as compared to flat substrates. After seeding on flat substrates, cells displayed large and spread nucleus and cytoplasm, while cells cultured in the 3D Nichoid were spatially organized in three dimensions, with smaller and spherical nuclei. Gene expression analysis revealed the upregulation of genes related to stemness and to mesenchymal stem cells’ features in Nichoid-cultured cells, as compared to flat substrates. The observed changes in cytoskeletal organization of cells cultured on 3D Nichoids were also responsible for a different localization of the mechanotransducer transcription factor YAP, with an increase of the cytoplasmic retention in cells cultured in the 3D Nichoid. This difference could be explained by alterations in the import of transcription factors inside the nucleus due to the observed decrease of mean nuclear pore diameter, by transmission electron microscopy. Our data show that 3D distribution of cell volume has a profound effect on mesenchymal stem cells structure and on their mechanobiological response, and highlight the potential use of the 3D Nichoid substrate to strengthen the potential effects of MSC in vitro and in vivo.
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Neumüller, Ulrich, Hannah Burger, Antonia V. Mayr, Sebastian Hopfenmüller, Sabrina Krausch, Nadine Herwig, Ronald Burger, et al. "Artificial Nesting Hills Promote Wild Bees in Agricultural Landscapes." Insects 13, no. 8 (August 14, 2022): 726. http://dx.doi.org/10.3390/insects13080726.
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The availability of nesting resources influences the persistence and survival of bee communities. Although a positive effect of artificial nesting structures has frequently been shown for aboveground cavity-nesting wild bees, studies on below ground-nesting bees are rare. Artificial nesting hills designed to provide nesting habitats for ground-nesting bees were therefore established within the BienABest project in 20 regions across Germany. Wild bee communities were monitored for two consecutive years, accompanied by recordings of landscape and abiotic nest site variables. Bee activity and species richness increased from the first to the second year after establishment; this was particularly pronounced in landscapes with a low cover of semi-natural habitat. The nesting hills were successively colonized, indicating that they should exist for many years, thereby promoting a species-rich bee community. We recommend the construction of nesting hills on sun-exposed sites with a high thermal gain of the substrate because the bees prefer south-facing sites with high soil temperatures. Although the soil composition of the nesting hills plays a minor role, we suggest using local soil to match the needs of the local bee community. We conclude that artificial nesting structures for ground-nesting bees act as a valuable nesting resource for various bee species, particularly in highly degraded landscapes. We offer a construction and maintenance guide for the successful establishment of nesting hills for bee conservation.
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Wibowo, Eko Setio, Edy Yuwono, Purnama Sukardi, and Asrul Sahri Siregar. "Survival Rate, Growth And Chemical Content of Dendronereis pinnaticirris (Polychaeta, Nereidae) In Maintenance With Different Food And Substrate." ILMU KELAUTAN: Indonesian Journal of Marine Sciences 25, no. 2 (May 20, 2020): 75–84. http://dx.doi.org/10.14710/ik.ijms.25.2.75-84.
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The worm Dendronereis pinnaticirris is used as feed of shrimp broodstock in a hatchery, mainly because of its availability in the local market, and its nutritional content required for improving gonad maturation and post larvae production. The important economic value of the worm and the increasing demand for feed in shrimp hatcheries have led to an intense exploitation that suppers its population and the sustainability of the whole estuarine ecosystem. The study, which represents the starting point of large-scale production of the polychaete worm by culture in the artificial system, shall be undertaken. Accordingly, a production study using D. pinnaticirris juvenile was carried out under controlled conditions fed with two different feed (feed contains mainly plant protein and animal protein, respectively), and kept in three different substrates (substrate consists of mud and 8.78%, 37.34%, 39.17% sand, respectively). The treatments were arranged according to randomized completely block design in 8 (eight) replicates. The survival rate, body weight increment and growth, oxygen consumption, proximate body chemical, and fatty acid contents were measured. The results showed that growth and oxygen consumption was significantly influenced by a substrate and feed type (P<0.05). Worms on the mud substrate with 39.17% sand, and feed containing vegetable protein showed the highest oxygen consumption. Survival rate and chemical body content were not significantly influenced by the type of substrate and feed (P<0.05). The protein content of the worm was 32.02-43.81%, while fat content was 2.41-9.89%. Twenty different fatty acids were identified in the worm of all treatment groups.
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Xu, Chen, Zaohong Liu, Guanjun Cai, and Jian Zhan. "Experimental Study on the Retention and Interception Effect of an Extensive Green Roof (GR) with a Substrate Layer Modified with Kaolin." Water 12, no. 8 (July 30, 2020): 2151. http://dx.doi.org/10.3390/w12082151.
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Extensive green roofs (GRs) often appear as pollution sources during actual rainfall events; therefore, it is necessary to study the control of nutrient leaching in the substrate layer. In this study, four extensive GR experimental devices are built: two with artificial granular structure substrate layers improved with kaolin as a binder, one with a commercial substrate layer, and one with a standard roof (SR). Based on the simulated rainfall conditions in different local recurrence periods, the delayed outflow time, rainfall retention rate, event mean concentration (EMC), and cumulative pollutant quality of NH4+, NO3−, NO2−, and PO43− in the effluents were measured and evaluated. The results of the study indicate that under simulated rainfall in all the experimental design recurrence periods, the kaolin-modified substrate layer does not exhibit a more significant retention capacity than the commercial substrate. However, it does show some suppression of the leaching effect of NO3− and PO43− in the runoff. The reduction rate of cumulative NO3− quality is 6.56%, and PO43− is 10.54%. In future practical engineering and related research, attention should be paid to the influence of the type and addition amount of the substrate layer modifier on the stability of the granular structure to prevent nutrient loss caused by soil erosion.
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SELLIER, M., and S. PANDA. "SURFACE TEMPERATURE RECONSTRUCTION BASED ON THE THERMOCAPILLARY EFFECT." ANZIAM Journal 52, no. 2 (October 2010): 146–59. http://dx.doi.org/10.1017/s1446181111000654.
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AbstractA thin liquid film subject to a temperature gradient is known to deform under the action of thermocapillary stresses which induce convective cells. The free surface deformation can be thought of as the signature of the imposed temperature gradient, and this study investigates the inverse problem of trying to reconstruct the temperature field from known free surface variations. The present work builds on the analysis of Tan et al. [“Steady thermocapillary flows of thin liquid layers I. Theory”, Phys. Fluids A2 (1990) 313–321, doi:10.1063/1.857781] which provides a long-wave evolution equation for the fluid film thickness variation on nonuniformly heated substrates and proposes a solution strategy for the planar flow version of this inverse problem. The present analysis reveals a particular case for which there exists an explicit, closed-form solution expressing the local substrate temperature in terms of the local film thickness and its spatial derivatives. With some simplifications, this analysis also shows that this solution applies to three-dimensional flows. The temperature reconstruction strategies are successfully tested against “artificial” experimental data (obtained by solving the direct problem for known temperature profiles) and actual experimental data.
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Ng, Kiat, Tony Thomas, Michael R. Phillips, Helena Calado, Paulo Borges, and Fernando Veloso-Gomes. "Multifunctional artificial reefs for small islands." Progress in Physical Geography: Earth and Environment 39, no. 2 (March 31, 2015): 220–57. http://dx.doi.org/10.1177/0309133314567581.
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Multifunctional artificial reefs (MFARs) have been growing in popularity over the last decade. They are offshore submerged structures which provide coastal protection while also enhancing marine and recreational amenities such as surfing and beach widening. A feasibility study was undertaken for São Miguel Island (Azores) where island-wide general site-selection criteria and local site-specific parameters identified São Roque reef as a potential MFAR location. Expert knowledge addressed multidisciplinary aspects through semi-guided interviews, which provided evaluation criteria for the São Roque reef development. Wave changes before and after reef reprofiling were determined using the Regional Coastal Process WAVE propagation model (CEDAS/RCPWAVE). Results demonstrated additional coastal protection to the historic church and existing seawalls, and no adverse effects on the updrift São Roque and downdrift Pópulo Milicias beaches. Further simulation for an extended reef (30 m seaward) showed model sensitivity together with a greater reduction in approaching wave heights. This analysis suggested that the further seaward the reef is extended, the greater the coastal protection afforded. It also denoted longer, rideable surfing waves and greater substrate surface area for marine colonization, while conversely having an increasing effect on downdrift Pópulo Milicias beach, construction costs and footprint impact. An optimal solution will provide a balance to these advantages and disadvantages. A SWOT analysis showed the potential of capitalizing internal strengths and external opportunities to offset internal weaknesses and external threats. With global growing emphasis on the importance of incorporating amenity values into coastal protection works, this research informs alternative solutions for other small islands, especially similar small volcanic islands.
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Wright, Serena R., Christopher P. Lynam, David A. Righton, Julian Metcalfe, Ewan Hunter, Ainsley Riley, Luz Garcia, Paulette Posen, and Kieran Hyder. "Structure in a sea of sand: fish abundance in relation to man-made structures in the North Sea." ICES Journal of Marine Science 77, no. 3 (October 26, 2018): 1206–18. http://dx.doi.org/10.1093/icesjms/fsy142.
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Abstract Artificial structures in the marine environment may have direct and/or indirect impact on the behaviour and space use of mobile foragers. This study explores whether environmental and physical features in the North Sea—including artificial structures (wrecks, wind turbines, cables, and oil and gas structures) were associated with local abundance of three fish species: cod (Gadus morhua), plaice (Pleuronectes platessa), and thornback ray (Raja clavata). Generalized additive models (GAMs) were used to compare distributions between data collected by fisheries surveys and electronic tags. Distributions of cod, plaice, and ray were correlated with environmental variables including temperature, depth, and substrate, matching findings from previous studies. All species showed seasonal increases in their abundance in areas with high densities of artificial structures, including oil and gas platforms and wrecks. Independent of whether fish purposefully associate with these features or whether structures happen to coincide with locations frequented by these populations, the strong association suggests that greater consideration needs to be given to regulation of habitat alterations, including decommissioning.
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Martel, André, Andrea F. Mathieu, C. Scott Findlay, Stephen J. Nepszy, and Joseph H. Leach. "Daily Settlement Rates of the Zebra Mussel, Dreissena polymorpha, on an Artificial Substrate Correlate with Veliger Abundance." Canadian Journal of Fisheries and Aquatic Sciences 51, no. 4 (April 1, 1994): 856–61. http://dx.doi.org/10.1139/f94-084.
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The relationship between daily settlement rates and local concentrations of veligers of the zebra mussel, Dreissena polymorpha, was investigated using plankton sampling and scouring pad collectors. A total of 102 plankton and 136 collector samples were taken from a nearshore site near Wheatley, Ontario, in west-central Lake Erie, over 17 consecutive d in August 1992. Results demonstrate a strong correlation between daily settlement rates and daily concentrations of late-stage (competent) veligers in the water column (determined at shell lengths ≥ 170 μm; r = 0.93–0.98; p < 0.001; log10-transformed data). Variations in settlement rates of 1–3 orders of magnitude occurred within 24–96 h. Results also suggest that wind-induced hydrodynamics can affect settlement rates of zebra mussel larvae; the period used to monitor settlement (24 h) was much shorter than that employed (~1–2+ wk) in previous studies. Daily monitoring of concentrations of late-stage veligers in the water column as well as settlers (fibrous collectors) may help to identify biological and physical factors affecting short-term variability in settlement; it may also prove advantageous for industries where early detection of colonization by the zebra mussel is critical for cost-effective control of this invasive mollusc.
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Isdianto, Andik, Oktiyas Muzaky Luthfi, Maulana Fikri, Muchamad Fairuz Haykal, and Supriyadi Supriyadi. "Actualize The Coastal Ecosystem Resilience : Determining The Location Of Artficial Reef." Journal of Innovation and Applied Technology 6, no. 2 (December 15, 2020): 1059–68. http://dx.doi.org/10.21776/ub.jiat.2020.006.02.8.
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Oceanographic parameters that affect coral reef growth are clarity, temperature, salinity and water currents taken at 20 stations using AAQ Rinko 1183 and FLOWATCH FL-03 current meter. The data processing using the IDW (Inverse Distance Weighted) interpolation method and the determination of the suitability area through scoring and weighting. The identification value consist of: (a) Clarity ranges from 2 - 6 meters, (b) Water turbidity ranges from 0.3 - 4.32 NTU, (c) Bottom substrate type is fine black sand, (d) Current velocity ranges from 0.1 m/s - 0.4 m/s, and (e) TSS ranges from 35.6 - 351 mg / L. The suitability of placing artificial reefs is classified at the appropriate level (S2), as a support for the survival of fishermen and local communities in Damas Beach, Trenggalek Regency
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Denton, Jonathan S., and Trevor J. C. Beebee. "An evaluation of methods for studying natterjack toads (Bufo calamita) outside the breeding season." Amphibia-Reptilia 13, no. 4 (1992): 365–74. http://dx.doi.org/10.1163/156853892x00067.
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AbstractWe have investigated methods for finding natterjack toads (Bufo calamita) outside the breeding season at a range of sites in England. Success in locating toads in burrows or in other natural refugia was very variable between sites, depending on the nature of the substrate and availability of accessible alternative hiding places. Provision of artificial refugia (flat tiles) was also variable in success rate depending on local conditions, and even at the best site, tile use was highly seasonal with maxima in spring and autumn. Night searching was the most successful method for finding toads, readily applicable to all sites and facilitating contact with around 10% of the population in a single night, especially when weather conditions were optimal (i.e. after rain and with air temperatures above 9° C).
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de Munck, C. S., A. Lemonsu, R. Bouzouidja, V. Masson, and R. Claverie. "The GREENROOF module (v7.3) for modelling green roof hydrological and energetic performances within TEB." Geoscientific Model Development Discussions 6, no. 1 (February 20, 2013): 1127–72. http://dx.doi.org/10.5194/gmdd-6-1127-2013.
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Abstract. The need to prepare cities for climate change adaptation requests the urban modeller community to implement within their models sustainable adaptation strategies to be tested against specific city morphologies and scenarios. Greening city roofs is part of these strategies. In this context, a GREENROOF module for TEB (Town Energy Balance) has been developed to model the interactions between buildings and green roof systems at the scale of the city. This module allows one to describe an extensive green roof composed of four functional layers (vegetation – grasses or sedums, substrate, retention/drainage layers and artificial roof layers) and to model vegetation-atmosphere fluxes of heat, water and momentum, as well as the hydrological and thermal fluxes throughout the substrate and the drainage layers, and the thermal coupling with the structural building envelope. TEB-GREENROOF (v7.3) is therefore able to represent the impact of climate forcings on the functioning of the green roof vegetation and, conversely, the influence of the green roof on the local climate. A calibration exercise to adjust the model to the peculiar hydrological characteristics of the substrates and drainage layers commonly found on green roofs is performed for a case study located in Nancy (France) which consists of an extensive green roof with sedums. Model results for the optimum hydrological calibration show a good dynamics for the substrate water content which is nevertheless under-estimated but without impacting too much the green roof temperatures since they present a good agreement with observations. These results are encouraging with regard to modelling the impact of green roofs on thermal indoor comfort and energy consumption at the scale of cities, for which GREENROOF will be running with the building energy version of TEB, TEB-BEM. Moreover, the green roof studied for GREENROOF evaluation being a city-widespread type of extensive green roof, the hydrological characteristics derived through the evaluation exercise will be used as the standard configuration to model extensive green roofs at the scale of cities.
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Aponso, S., J. G. Ummadi, H. Davis, J. Ferracane, and D. Koley. "A Chemical Approach to Optimizing Bioactive Glass Dental Composites." Journal of Dental Research 98, no. 2 (November 21, 2018): 194–99. http://dx.doi.org/10.1177/0022034518809086.
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The chemical microenvironment surrounding dental composites plays a crucial role in controlling the bacteria grown on these specialized surfaces. In this study, we report a scanning electrochemical microscopy (SECM)–based analytic technique to design and optimize metal ion-releasing bioactive glass (BAG) composites, which showed a significant reduction in biofilm growth. SECM allows positioning of the probe without touching the substrate while mapping the chemical parameters in 3-dimensional space above the substrate. Using SECM and a solid-state H+ and Ca2+ ion-selective microprobe, we determined that the local Ca2+ concentration released by different composites was 10 to 224 µM for a BAG particle size of <5 to 150 µm in the presence of artificial saliva at pH 4.5. The local pH was constant above the composites in the same saliva solution. The released amount of Ca2+ was determined to be maximal for particles <38 µm and a BAG volume fraction of 0.32. This optimized BAG-resin composite also showed significant inhibition of biofilm growth (24 ± 5 µm) in comparison with resin-only composites (53 ± 6 µm) after Streptococcus mutans bacteria were grown for 3 d in a basal medium mucin solution. Biofilm morphology and its subsequent volume, as determined by the SECM imaging technique, was (0.59 ± 0.38) × 107 µm3 for BAG-resin composites and (1.29 ± 0.53) × 107 µm3 for resin-only composites. This study thus lays the foundation for a new analytic technique for designing dental composites that are based on the chemical microenvironment created by biomaterials to which bacteria have been exposed.
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Buhrle, C. P., L. Rosivall, and R. Taugner. "Intrarenal generation of angiotensin II evaluated by an electrophysiological technique." American Journal of Physiology-Renal Physiology 252, no. 4 (April 1, 1987): F635—F644. http://dx.doi.org/10.1152/ajprenal.1987.252.4.f635.
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Angiotensin II (ANG II) reversibly depolarizes renin-containing juxtaglomerular epithelioid cells (JGECs) of the hydronephrotic mouse kidney afferent arteriole. This depolarizing response was utilized to assess changes in ANG II concentration in the vicinity of JGECs in order to test whether ANG II is generated from ANG I and artificial renin substrate (ARS) in this preparation. Depolarizations were also produced by the application of ANG I and ARS in the superfusing medium. These responses to ANG I and ARS were completely blocked by saralasin. Hence, our findings are indicative for an intrarenal, local generation of ANG II. As opposed to saralasin, several converting enzyme and renin inhibitors only diminished but generally did not abolish the actions of ANG I and ARS, respectively. These results suggest an alternative, nonrenin and non-converting enzyme-dependent pathway of ANG II generation in renal tissue.
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de Munck, C. S., A. Lemonsu, R. Bouzouidja, V. Masson, and R. Claverie. "The GREENROOF module (v7.3) for modelling green roof hydrological and energetic performances within TEB." Geoscientific Model Development 6, no. 6 (November 8, 2013): 1941–60. http://dx.doi.org/10.5194/gmd-6-1941-2013.
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Abstract. The need to prepare cities for climate change adaptation requests the urban modeller community to implement sustainable adaptation strategies within their models to be tested against specific city morphologies and scenarios. Greening city roofs is part of these strategies. In this context, the GREENROOF module for TEB (town energy balance) has been developed to model the interactions between buildings and green roof systems at the scale of the city. This module, which combines the ISBA model (Interaction between Soil Biosphere and Atmosphere) and TEB, allows for one to describe an extensive green roof composed of four functional layers (vegetation – grasses or sedums; substrate; retention/drainage layers; and artificial roof layers) and to model vegetation-atmosphere fluxes of heat, water and momentum, as well as the hydrological fluxes throughout the substrate and the drainage layers, and the thermal fluxes throughout the natural and artificial layers of the green roof. TEB-GREENROOF (SURFEX v7.3) should therefore be able to represent the impact of climate forcings on the functioning of green roof vegetation and, conversely, the influence of the green roof on the local climate. An evaluation of GREENROOF is performed for a case study located in Nancy (France) which consists of an instrumented extensive green roof with sedums and substrate and drainage layers that are typical of this kind of construction. After calibration of the drainage layer hydrological characteristics, model results show good dynamics for the substrate water content and the drainage at the green roof base, with nevertheless a tendency to underestimate the water content and overestimate the drainage. This does not impact too much the green roof temperatures, which present a good agreement with observations. Nonetheless GREENROOF tends to overestimate the soil temperatures and their amplitudes, but this effect is less important in the drainage layer. These results are encouraging with regard to modelling the impact of green roofs on thermal indoor comfort and energy consumption at the scale of cities, for which GREENROOF will be running with the building energy version of TEB – TEB-BEM. Moreover, with the green roof studied for GREENROOF evaluation being a type of extensive green roof widespread in cities, the type of hydrological characteristics highlighted for the case study will be used as the standard configuration to model extensive green roof impacts at the scale of cities.
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Ustun, Deniz, and Ali Akdagli. "Design of a dual-wideband monopole antenna by artificial bee colony algorithm for UMTS, WLAN, and WiMAX applications." International Journal of Microwave and Wireless Technologies 9, no. 5 (December 21, 2016): 1197–208. http://dx.doi.org/10.1017/s1759078716001355.
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In this study, a dual-wideband monopole antenna has been designed and developed for the universal mobile telecommunications system (UMTS), wireless local area network (WLAN), and worldwide interoperability for microwave access (WiMAX) applications. A novel approach integrating artificial bee colony (ABC) with the HyperLynx® 3D electromagnetic platform based on the method of moments has been employed to calculate the design parameters of the monopole antenna performance for the respective target frequencies and return loss. The proposed dual-wideband antenna operates in the dual-frequency ranges of 1.69–3.99 and 4.75–6.22 GHz applicable for the UMTS, WLAN, and WiMAX applications and it is fabricated on the flame resistant-4 substrate plate of 42 × 51 × 1.6 mm3. The performance of the presented monopole antenna is analyzed in terms of gain, radiation pattern, and s-parameter. The input reflection coefficient (S11) parameter and radiation pattern of the antenna are verified through the measurements. The measured values of the antenna parameters are found to match well within tolerable limits with the simulation results. The results illustrate that the presented dual-wideband monopole antenna obtained by using the ABC algorithm exhibits better performance in point of operating bands and s-parameter as compared with the multi-band antennas previously published in the literature.
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Nguyen, Lan. "A New Metasurface Structure for Bandwidth Improvement of Antenna Array." Applied Computational Electromagnetics Society 36, no. 2 (March 16, 2021): 139–44. http://dx.doi.org/10.47037/2020.aces.j.360204.
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In this paper, the design of an antenna array with enhanced bandwidth is presented. The antenna array includes 16 elements (4 x 4) based on RT5880 with height of 1.575 mm, dielectric constant of 2.2 and loss tangent of 0.0009 and it is yielded at the central frequency of 5.8 GHz for Wireless Local Area Network (WLAN) applications. In addition, in order to enhance bandwidth for antenna, the paper proposes a new metasurface. The metasurface, which is a lattice of 3 x 3 cells, is printed on a substrate of FR4 (h = 1.6 mm, ɛr = 4.4, and tanδ = 0.02) and it acts as an artificial magnetic conductor reflector. The final prototype with an overall dimension of 123 x 120 x 3.315 mm3 was fabricated and measured. The antenna witnesses an impedance bandwidth of 5.1-7.5 GHz at -10 dB (41%) and a peak gain of 17.65 dBi for measurement. The simulation results are confirmed by measurement ones to verify the performance of the proposed antenna.
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Sackmann, E. "Molecular and global structure and dynamics of membranes and lipid bilayers." Canadian Journal of Physics 68, no. 9 (September 1, 1990): 999–1012. http://dx.doi.org/10.1139/p90-142.
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The cell plasma is a composite type of material that is made up of a two-dimensional liquid crystal (lipid–protein bilayer) to which a macromolecular network (the cytoskeleton) is loosely coupled. The latter may be approximately two dimensional as in the case of the erythrocytes or may extend throughout the whole cell cytoplasm. Owing to this combination of two states of matter, the membrane combines the dynamics and flexibility of a fluid with the mechanical stability of a solid. Owing to its low dimensionality, the local structure of the bilayer or the global shape of cells may be most effectively controlled and modulated by biochemical signals such as macromolecular adsorption. The present contribution deals with comparative studies of the local and global dynamic properties of biological and artificial membranes. In the first part the question of the physical basis of selective lipid–protein interaction mechanisms is addressed and the outstanding viscoelastic properties of plasma membranes and their role for local instabilities shape fluctuations of cells and the cell–substrate interaction are described. The second part deals with the molecular architecture and dynamics of composite membranes prepared by combining monomeric and macromolecular lipids. These model membranes open new possibilities to mimick complex mechanical processes of cell plasma membranes and to prepare low-dimensionality macromolecular solutions and gels. Finally, the use of such compound systems by nature to prepare the semipermeable protective layers of plant leaves, the so-called cuticle, is discussed. In analogy to plasma membranes, the local transport properties are modulated by variation of the liquid-crystalline state of the monomeric waxes.
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Will, Bruno, Christian Kelche, and Jean-Christophe Cassel. "Intracerebral Transplants and Memory Dysfunction: Circuitry Repair or Functional Level Setting?" Neural Plasticity 7, no. 1-2 (2000): 93–108. http://dx.doi.org/10.1155/np.2000.93.
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Intracerebral grafting techniques of fetal neural cells have been used essentially with two main types of lesion paradigms, namely damage to long projection systems, in which the source and the target are clearly separate, and damage to neurons that are involved in local circuits within a small (sub)region of the brain. With the’first lesion paradigm, grafts placed homotopically (in the source) are not appropriate because their fibers grow poorly through the host parenchyma and fail to reach their normal target. To be successful, the grafts must be placed ectopically in the target region of the damaged projection systems, where generally they work as level-setting systems. Conversely, with the second paradigm, the grafts are supposed to compensate for a local loss of neurons and must be placed homotopically to induce functional effects that are based on the reconstruction of a point-to-point circuitry. By inserting a biological or artificial bridging-substrate between the source and the target of long projection systems, it might be possible to combine the positive effects of both homotopic and ectopic grafting by achieving both target reinnervation and normal control of the grafted neurons within the source area. These issues are illustrated and discussed in this review.
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Consoli, Pierpaolo, Andrea Martino, Teresa Romeo, Mauro Sinopoli, Patrizia Perzia, Simonepietro Canese, Pietro Vivona, and Franco Andaloro. "The effect of shipwrecks on associated fish assemblages in the central Mediterranean Sea." Journal of the Marine Biological Association of the United Kingdom 95, no. 1 (July 17, 2014): 17–24. http://dx.doi.org/10.1017/s0025315414000940.
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Understanding the role played by sunken vessels in Mediterranean marine ecosystems is acquiring increasing importance. The aim of this research was to study the fish communities associated with four shipwrecks, by means of underwater visual censuses performed by a remotely operated vehicle, and to test the differences in composition of fish assemblages between these shipwrecks and the adjacent soft bottoms, considered as control sites. Multivariate analysis on the total fish assemblage showed significant differences between wrecks and controls. Results also showed higher levels of species richness and abundance near all wrecks than at a short distance from them on soft bottoms, thus indicating that these sunken vessels, thanks to their higher habitat complexity, act as artificial reefs, attracting aggregations of fish species and leading to a greater diversification of the local fish assemblage. Nevertheless, shipwrecks, which are an ideal target for recreational fishermen, could contribute to the over-exploitation of some high-value fish species, such asMycteroperca rubra, Dentex dentexandDiplodusspp., attracted by the artificial hard substrate of the vessel-reefs. The recent European directives suggest an urgent need for a better understanding of the crucial role played by these potential sources of pollutants on marine environments and ecosystems. An ecosystem approach to study and monitor these pollutant sources is, therefore, mandatory for appropriate remediation and/or mitigation of the potential negative effects on a productive and healthy ocean.
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Beaudot, W. H. A. "A Neuromorphic Recurrent Model for Figure-Ground Segregation of Coherent Motion." Perception 26, no. 1_suppl (August 1997): 84. http://dx.doi.org/10.1068/v970195.
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A neuromorphic model of the retino-cortical motion processing stream is proposed which incorporates both feedforward and feedback mechanisms. The feedforward stream consists of motion integration from the retina to the MT area. Retinal spatiotemporal filtering provides X-like and Y-like visual inputs with band-pass characteristics to the V1 area (Beaudot, 1996 Perception25 Supplement, 30 – 31). V1 direction-selective cells respond to local motion resulting from nonlinear interactions between retinal inputs. MT direction-selective cells respond to global motion resulting from spatial convergence and temporal integration of V1 signals. This feedforward stream provides a fine representation of local motion in V1 and a coarse representation of global motion in MT. However, it is unable to deal with the aperture problem. Solving this problem requires the adjunction of local constraints related to both smoothness and discontinuity of coherent motion, as well as some minimisation techniques to obtain the optimal solution. We propose a plausible neural substrate for this computation by incorporating excitatory intracortical feedbacks in V1 and their modulation by reciprocal connections from MT. The underlying enhancement or depression of V1 responses according to the strength of MT responses reflects changes in the spatiotemporal properties of the V1 receptive fields. This mechanism induces a dynamic competition between local and global motion representations in V1. On convergence of these dynamics, responses of V1 direction-selective cells provide a fine representation of ‘true’ motion, thus solving the aperture problem and allowing a figure - ground segregation based on coherent motion. The model is compatible with recent anatomical, physiological, and psychophysical evidence [Bullier et al, 1996 Journal de Physiologie (Paris)90 217 – 220].
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Han, Zhongying, and Xiaoguang Huang. "GA-BP in Thermal Fatigue Failure Prediction of Microelectronic Chips." Electronics 8, no. 5 (May 14, 2019): 542. http://dx.doi.org/10.3390/electronics8050542.
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A thermal fatigue life prediction model of microelectronic chips based on thermal fatigue tests and solder/substrate interfacial singularity analysis from finite element method (FEM) analysis is established in this paper. To save the calculation of interfacial singular parameters of new chips for life prediction, and improve the accuracy of prediction results in actual applications, a hybrid genetic algorithm–artificial neural network (GA–ANN) strategy is utilized. The proposed algorithm combines the local searching ability of the gradient-based back propagation (BP) strategy with the global searching ability of a genetic algorithm. A series of combinations of the dimensions and thermal mechanical properties of the solder and the corresponding singularity parameters at the failure interface are used to train the proposed GA-BP network. The results of the network, together with the established life prediction model, are used to predict the thermal fatigue lives of new chips. The comparison between the network results and thermal fatigue lives recorded in experiments shows that the GA-BP strategy is a successful prediction technique.
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Higgins, Emily, Anna Metaxas, and Robert E. Scheibling. "A systematic review of artificial reefs as platforms for coral reef research and conservation." PLOS ONE 17, no. 1 (January 21, 2022): e0261964. http://dx.doi.org/10.1371/journal.pone.0261964.
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Artificial reefs (ARs) have been used on coral reefs for ecological research, conservation, and socio-cultural purposes since the 1980s. We examined spatio-temporal patterns in AR deployment in tropical and subtropical coral reefs (up to 35° latitude) and evaluated their efficacy in meeting conservation objectives, using a systematic review of the scientific literature. Most deployments (136 studies) were in the North Atlantic and Central Indo-Pacific in 1980s – 2000s, with a pronounced shift to the Western Indo-Pacific in 2010s. Use of ARs in reef restoration or stressor mitigation increased markedly in response to accelerating coral decline over the last 2 decades. Studies that evaluated success in meeting conservation objectives (n = 51) commonly reported increasing fish abundance (55%), enhancing habitat quantity (31%) or coral cover (27%), and conserving target species (24%). Other objectives included stressor mitigation (22%), provision of coral nursery habitat (14%) or source populations (2%) and addressing socio-cultural and economic values (16%). Fish (55% of studies) and coral (53%) were the most commonly monitored taxa. Success in achieving conservation objectives was reported in 33 studies. Success rates were highest for provision of nursery habitat and increasing coral cover (each 71%). Increasing fish abundance or habitat quantity, mitigating environmental impacts, and attaining socio-cultural objectives were moderately successful (60–64%); conservation of target species was the least successful (42%). Failure in achieving objectives commonly was attributed to poor AR design or disruption by large-scale bleaching events. The scale of ARs generally was too small (m2 –10s m2) to address regional losses in coral cover, and study duration too short (< 5 years) to adequately assess ecologically relevant trends in coral cover and community composition. ARs are mostly likely to aid in reef conservation and restoration by providing nursery habitat for target species or recruitment substrate for corals and other organisms. Promoting local socio-cultural values also has potential for regional or global impact by increasing awareness of coral reef decline, if prioritized and properly monitored.
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Rossano, C., G. di Cristina, and F. Scapini. "Life cycle and behavioural traits of Dikerogammarus villosus (Sowinsky, 1894) (Amphipoda, Gammaridae) colonising an artificial fresh water basin in Tuscany (central Italy)." Crustaceana 86, no. 7-8 (2013): 908–31. http://dx.doi.org/10.1163/15685403-00003211.
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The water amphipod Dikerogammarus villosus (Sowinsky, 1894) has colonised many rivers and water basins in central Europe and is rapidly reaching southern Europe. It was found in northern Italy in 2006 and in central Italy in 2008. In this last area it has colonised the recent artificial basin of Bilancino (Mugello Valley, Florence), currently being the only and abundant amphipod species in the lake. This new population offered a good opportunity to study the life cycle and behaviour of such unpopular species (called killer shrimp because of its aggression), with the aim of better understanding the mechanisms of survival and diffusion of water gammarids. For about one year and a half, bimonthly samplings were carried out in different points of the lake to study the life cycle and identify the most suitable populations for behavioural experiments. On this species experiments were carried out in the natural context to verify sun and landscape orientation and in the laboratory to analyse the response to a black boundary, direct light and substrate slope. The populations from the different points had a comparable structure and development, even if subjected to variations linked to the local features of the lake’s bottom. The response to the black boundary (simulating a predator or a refuge) was not significant, while a significant reaction of avoidance of a direct artificial light and a significant preference for the basin bottom (downslope) were observed. No specific responses were identified where the behaviour was strictly linked to the environment colonised (orientation to the sun and natural landscape). A lack of fine-tuned adaptations was expected in this species that has colonised a variety of environments, confirming comparable results on the physiology of this species, such as adaptation to wide ranges of temperature, salinity and oxygen levels.
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Trbojevic, Ivana, Dragana Predojevic, Gordana Subakov-Simic, and Jelena Krizmanic. "Periphytic diatoms in the presence of a cyanobacterial bloom: A case study of the Vrutci Reservoir in Serbia." Archives of Biological Sciences 71, no. 2 (2019): 215–23. http://dx.doi.org/10.2298/abs181120003t.
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Despite their unique ecology and implications for ecological assessment, diatoms in lentic ecosystems are still insufficiently studied in both scientific research and operational monitoring. In particular, the ecology of periphytic diatoms relative to the global expansion of cyanobacterial blooms in lakes has not been described at all. This study aims to describe the diversity and dynamics of a periphytic diatom community in the Vrutci Reservoir during Planktothrix rubescens bloom, and to evaluate the adequacy of standard diatom index implementation in lentic ecosystems relative to the diatom index adapted for lakes ? the Trophic Diatom Index for Lakes (TDIL). The study was conducted in the Vrutci Reservoir in western Serbia. Periphyton was developed on an artificial glass substrate during the summer of 2015, following a depth gradient of a stratified water column. Diatom diversity and abundance, as well as diatom indices were estimated. Discounting the cyanobacterial bloom, 79 taxa of diatoms were recorded and among them the species Aneumastus stroesei as the first representative of the entire genus Aneumastus ever to be detected in Serbia. Diatom distribution along the depth gradient was clearly associated with shifts in environmental conditions. TDIL showed an advantage over standard diatom indices in terms of stability during experimental period and uniformity along the depth gradient, indicating the necessity for further testing of this index performance in lakes, and consequently local water-quality legislation update.
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BRAUN, K. F., F. MORESCO, K. MORGENSTERN, S. FÖLSCH, J. REPP, S. W. HLA, G. MEYER, and K. H. RIEDER. "MANIPULATION OF ATOMS AND MOLECULES FOR CONSTRUCTION OF NANOSYSTEMS: THE SCANNING TUNNELING MICROSCOPE AS AN OPERATIVE TOOL." International Journal of Nanoscience 02, no. 04n05 (August 2003): 197–218. http://dx.doi.org/10.1142/s0219581x03001218.
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Controlled manipulations with scanning tunneling microscope (STM) down to the scale of small molecules and single atoms allow to build molecular and atomic nanosystems, leading to the fascinating possibility of creating manmade structures on atomic scale. Here we present a short review on investigations based on atomic scale manipulation. Upon soft lateral manipulation of adsorbed species, in which only tip/particle forces are used, three different manipulation modes can be discerned: pushing, pulling and sliding. Even the manipulation of strongly bound native substrate atoms is possible. We demonstrate applications as local analytic and synthetic chemistry tools, with important consequences on surface structure research. Vertical manipulation of Xe and CO leads to improved imaging with functionalized tips. With CO deliberately transferred to the tip, we have also succeeded to perform vibrational spectroscopy on single molecules. Furthermore, we describe how we have reproduced a full chemical reaction with single molecules, whereby all basic steps, namely preparation of the reactants, diffusion and association, are induced with the STM tip. Here also field and electron current effects are employed. Finally, we have extended the manipulation techniques to large specially designed molecules by performing lateral manipulation in constant height and realizing the principle of a conformational molecular switch. Artificial nanoscale structures built in atom by atom fashion can serve as quantum laboratories for investigations of various physical properties.
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RETNANINGDYAH, CATUR, ENDANG ENDANG ARISOESILANINGSIH, and SETIJONO SAMINO. "Use of local Hydromacrophytes as phytoremediation agent in pond to improve irrigation water quality evaluated by Diatom Biotic Indices." Biodiversitas Journal of Biological Diversity 18, no. 4 (October 7, 2017): 1611–17. http://dx.doi.org/10.13057/biodiv/d180439.
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Retnaningdyah C, Arisoesilaningsih E, Samino S. 2017. Use of local Hydromacrophytes as phytoremediation agent in pond to improve irrigation water quality evaluated by Diatom Biotic Indices. Biodiversitas 18: 1596-1602. Irrigation water in Indonesia generally has been polluted because of agricultural, industrial and domestic activity. The aims of this research were to determine the effectiveness of phytoremediation models conducted by planting some local Hydromacrophytes in three phytoremediation ponds through a continuous culture system with water discharge about 0.3 L/seconds for improving the irrigation water quality. The quasiexperimental research was conducted in a phytoremediation pond located in Kepanjen District of Malang, East Java Indonesia. The phytoremediation pond was divided into four interconnected sections. Pond 1 and 2 were planted with some of floating leaf and emergent hydromacrophyte, pond 3 was planted by combinations of same plants added with submerged Hydromacrophytes, while pond 4 was container pond to collecting the water as a result of phytoremediation process. The success of phytoremediation process was known from some physico-chemical parameters of water and some of diatom biotic indices (trophic diatom index/TDI, percentage of pollution tolerant value (%PTV), and Shannon Wiener diversity Index) that was found from artificial substrate been installed in the early treatment. The water quality monitoring performed in each part of the ponds after the plants grew steadily. The results showed that planting of Hydromacrophytes can significantly improve the physico-chemical quality of water. This was reflected in the decline value of conductivity (from 188 μS/cm to 182 μS/cm), turbidity (30 NTU become 8 NTU), total suspended solid (TSS) from 31.3 mg/L to be 5.5 mg/L, nitrates (7.5 mg/L to 3.3 mg/L) and dissolved phosphates (from 0.16 mg./L become 0.04 mg/L) and increasing value of dissolved oxygen (DO) in waters from 2.6 mg/L become 2.9 mg/L. Based on biotic indices there were improvement of the water quality from heavily polluted (diversity index 0.91) become moderately polluted (diversity index 2.07), eutrophic (TDI 52) become mesoeutrophic (TDI 38), and from heavily organic pollution (PTV 93%) to be some organic pollution contribute to eutrophication (PTV 38%). Improvement of water quality was effectively occur after passing through the third pond.
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Birchenough, Silvana N. R., and Steven Degraer. "Science in support of ecologically sound decommissioning strategies for offshore man-made structures: taking stock of current knowledge and considering future challenges." ICES Journal of Marine Science 77, no. 3 (April 16, 2020): 1075–78. http://dx.doi.org/10.1093/icesjms/fsaa039.
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Abstract The blue growth agenda has spurred an accelerating exploitation and continued development of the coastal and marine environment. This is also driven by the increasing need to generate renewable energy. In most cases, this has resulted in a large number of man-made structures (MMSs) across several soft sediment environments. The nature of these structures ranges from oil and gas installations to harbour walls, anchored buoys, pipelines and offshore wind farms. These structures host fouling communities that are often new to offshore regions, potentially serving as stepping stones for range-expanding (non-indigenous) species and providing habitat and shelter for a variety of marine species. The altered local biodiversity also affects biological and biogeochemical processes from the water column to the seafloor, either directly (e.g. scouring, organic matter export from piles) or indirectly (e.g. closure or displacement of fisheries) and, hence, ecosystem functioning at various spatial and temporal scales. A proper understanding of the effects of artificial hard substrate and the consequences of its removal (e.g. through decommissioning) to marine biodiversity has yet to develop to maturity. This themed article set contributes to the scientific knowledge base on the impacts of MMSs on marine ecosystems with the specific aim to fertilize and facilitate an evidence-based debate over decommissioning. This discussion will become ever more vital to inform marine spatial planning and future policy decisions on the use and protection of marine resources.
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Xie, Qinghua, Pengyu Chen, Zhaohuan Li, and Renfeng Xie. "Automatic Segmentation and Classification for Antinuclear Antibody Images Based on Deep Learning." Computational Intelligence and Neuroscience 2023 (February 8, 2023): 1–9. http://dx.doi.org/10.1155/2023/1353965.
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Antinuclear antibodies (ANAs) testing is the main serological diagnosis screening test for autoimmune diseases. ANAs testing is conducted principally by the indirect immunofluorescence (IIF) on human epithelial cell-substrate (HEp-2) protocol. However, due to its high variability and human subjectivity, there is an insistent need to develop an efficient method for automatic image segmentation and classification. This article develops an automatic segmentation and classification framework based on artificial intelligence (AI) on the ANA images. The Otsu thresholding method and watershed segmentation algorithm are adopted to segment IIF images of cells. Moreover, multiple texture features such as scale-invariant feature transform (SIFT), local binary pattern (LBP), cooccurrence among adjacent LBPs (CoALBP), and rotation invariant cooccurrence among adjacent LBPs (RIC-LBP) are utilized. Firstly, this article adopts traditional machine learning methods such as support vector machine (SVM), k-nearest neighbor algorithm (KNN), and random forest (RF) and then uses ensemble classifier (ECLF) combined with soft voting rules to merge these machine learning methods for classification. The deep learning method InceptionResNetV2 is also utilized to train on the classification of cell images. Eventually, the best accuracy of 0.9269 on the Changsha dataset and 0.9635 on the ICPR 2016 dataset for the traditional methods is obtained by a combination of SIFT and RIC-LBP with the ECLF classifier, and the best accuracy obtained by the InceptionResNetV2 is 0.9465 and 0.9836 separately, which outperforms other schemes.
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Sinyavina, N. G., A. A. Kochetov, G. V. Mirskaya, N. A. Rushina, G. G. Panova, and A. M. Artemieva. "STUDY OF THE RAPHANUS SATIVUS L. (SMALL RADISH) BIODIVERSITY UNDER CONDITIONS OF INTENSIVE LIGHT-CULTURE AND IDENTIFICATION OF DONORS OF ECONOMICALLY LUABLE CHARACTERS FOR BREEDING." Vegetable crops of Russia, no. 3 (July 25, 2018): 56–59. http://dx.doi.org/10.18619/2072-9146-2018-3-56-59.
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Supply of the domestic fresh vegetables commodity to the population of Northern regions of Russia is one of the most priority tasks of the national economy. Lack of the local, high-quality and adopted breeding material is highly problematic for breeding programs. Generation of the new, highly productive vegetable cultivars for the glass-covered ground, including light culture, will promote to expand significantly the volume of local production of vegetables in protected ground, especially in regions with a cold climate. One of the most prospective crops for protected ground is small radish, an early ripening crop with a valuable biochemical composition. А strategy for creation of the new, highly productive forms of small radish, beard predictable complex of economically valuable characters for growing in conditions of intensive light culture, has been developed in the Agrophysical Research Institute (SaintPetersburg). At the first stage, represent interspecific set of 26 small radish cultivars from different regions, was investigated in controlled conditions (artificial light, climate cell) to reveal a complex of economically valuable properties (early maturity, productivity, morphological traits). The plants were grown in original plant grooving light equipment (lamps DNaZ-400, photoperiod 12 hours, irradiation 15-20 klk), in a small volume of substrate (peat with mineral additives). It was observed that the small radish varieties have significant diversity in precocity, productivity, resistance to bolting, also they vary in a number of morphological features of roots and leaves. Bov, Estella, Rocco (Netherlands), Nobo Chind Criollo (Peru) were the most productive cultivars. They can produce yield of commercial roots during 30 days of vegetation up to 3.5 kg/m2. In addition, cultivars – genetic resources of economically valuable properties (compact rosette, glabrous leaf, resistance to bolting) were revealed for a breeding. Parent pairs for crossing were selected. It is planned to obtain offspring small radish forms with a complex of economically valuable properties, more productive than the parents. In all matched hybrid combinations, F1 hybrids were obtained. They have a degree of hybrid superiority in roots weight from 110 to 230% over the best of the parent form. They will become the ancestors of the original forms of small radish, intended for cultivation in conditions of intense light culture.
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KELLER, Christine. "Artificial substrata colonized by freshwater lichens." Lichenologist 37, no. 4 (July 2005): 357–62. http://dx.doi.org/10.1017/s0024282905014672.
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Small clay cubes, fired at different temperatures and mounted with nylon touch and close fastener (Velcro®) on acrylic glass plates, were used in an experimental design to study colonization of artificial substrata by lichens. The cubes were exposed in alpine streams for either 5–7 y at five different sites in the Swiss Alps: Flüelatal (three sites) and Brigels (Canton of Graubünden), and Eggerberg (Canton of Valais). Only a few cubes were lost, except at two sites, where complete plates were lost – due to the strong water current and, probably, trampling by cattle. After 3 y, freshwater lichens had grown at three sites. At the most elevated site, colonization was observed after 4 y; at one site no lichen growth was recorded. The first colonizers of the new substrata were the locally most common species. Freshwater lichens preferred the surfaces of clay cubes fired at lower temperature, whereas exposed pieces of local rocks were less frequently colonized. Improvements in the experimental design are suggested.
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Lister, Stephen, Vikash Venkataramana, Thomas Thomson, Joachim Kohlbrecher, Ken Takano, Yoshihiro Ikeda, Laura Heyderman, Luca Anghinolfi, Georg Heldt, and Stephen Lee. "A study of perpendicular magnetic recording media using polarized SANS." Acta Crystallographica Section A Foundations and Advances 70, a1 (August 5, 2014): C148. http://dx.doi.org/10.1107/s2053273314098519.
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The study of thin film magnetic systems that are structured on the nanoscale is an area of intense interest. Small-angle neutron scattering is an extremely powerful probe of nanomagnetism in the bulk, but in thin-film systems the experiments are challenging due both to the small scattering volume available and also to scattering from other sources such as the substrate and sample environment. We have demonstrated that such experiments are however possible in magnetic films as thin as 10 nm. A good example to illustrate this is the case of perpendicular magnetic recording media. These materials are found in all modern magnetic hard drives, the data storage technology that continues to be of tremendous commercial and technological importance. These media are advanced functional multilayered materials, containing an active recording layer of only around 10 nm in thickness. This recording layer is compositionally segregated into 8 nm-sized grains of a magnetic CoCrPt alloy separated by a thin oxide shell, typically SiO2. These media have their magnetic moments oriented perpendicular to the plane of the film. Determining the local magnetic structure and reversal behavior is key to understanding the performance of perpendicular media in recording devices. Polarised SANS has proved to be a very effective tool to measure these materials at a sub-10nm length scales. The signal of interest must however also be distinguished from the scattering from other layers in the structure, some of which are also magnetic. We will present a summary of some recent results on recording media, including measurements of the grain-sized dependent switching with and without the presence of an exchange spring. We will also briefly mention experiments that demonstrate the viability of extending this approach to measurement for lithographically defined structures similar to those for application in bit-patterned media, including 2d artificial spin-ice and structurally glassy arrays.
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Bietti, S., C. Somaschini, N. Koguchi, C. Frigeri, and S. Sanguinetti. "Self-assembled GaAs local artificial substrates on Si by droplet epitaxy." Journal of Crystal Growth 323, no. 1 (May 2011): 267–70. http://dx.doi.org/10.1016/j.jcrysgro.2010.12.036.
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Adeyeye, Samuel Ayofemi Olalekan, Olusola Timothy Bolaji, Titilope Adebusola Abegunde, and Taofeek Olawale Adesina. "Processing and utilization of snail meat in alleviating protein malnutrition in Africa: a review." Nutrition & Food Science 50, no. 6 (January 31, 2020): 1085–97. http://dx.doi.org/10.1108/nfs-08-2019-0261.
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Purpose This study aims to review processing and utilization of snail meat in alleviating protein malnutrition in Africa. Most countries in Africa are faced with a major challenge of protein malnutrition as a result of high cost of animal proteins. This has encouraged more research works in the use of wild or game meat to meet the much-needed animal proteins. Design/methodology/approach Previous literatures on the above subject matter were reviewed. In many African countries, the use of snails, rodents and other small livestock in the wild could help in improving the nutritional needs of the people in both urban and rural areas, as well as adding economic value through income generation to the local people. Findings Snails are very rich in dietary protein, low in fat and cholesterol and are good sources of iron, magnesium, calcium and zinc. Previous studies showed that snail meat contains 70 per cent of water and its dry matter contains high amounts of essential amino acids such as lysine, leucine, arginine and tryptophan. Research studies have shown that snail contains calcium orthophosphate, a chemical substrate that could alleviate and reduce kidney diseases. Also, the glandular substances found in edible snails were found to have antimicrobial activities that cause agglutination of certain bacteria, which could be used against some ailments like whooping cough. As snail meat products have high nutritional value, spoilage sets in after one or two days after harvesting, and therefore, the preservation of snail meat has become a major concern to farmers, processors and consumers. Several preservation techniques could be adopted, which include smoking, sun drying, convectional drying and the use of natural or artificial preservatives. These methods have been found to reduce microbial load of snail meat and help to extend shelf life and keeping quality of snail meat. Originality/value This review X-rayed the importance of snail meat in the human diet and how this could be explored to enhance protein nutrition in developing countries.
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Astor, J. C., and C. Adami. "A Developmental Model for the Evolution of Artificial Neural Networks." Artificial Life 6, no. 3 (July 2000): 189–218. http://dx.doi.org/10.1162/106454600568834.
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We present a model of decentralized growth and development for artificial neural networks (ANNs), inspired by developmental biology and the physiology of nervous systems. In this model, each individual artificial neuron is an autonomous unit whose behavior is determined only by the genetic information it harbors and local concentrations of substrates. The chemicals and substrates, in turn, are modeled by a simple artificial chemistry. While the system is designed to allow for the evolution of complex networks, we demonstrate the power of the artificial chemistry by analyzing engineered (handwritten) genomes that lead to the growth of simple networks with behaviors known from physiology. To evolve more complex structures, a Java-based, platform-independent, asynchronous, distributed genetic algorithm (GA) has been implemented that allows users to participate in evolutionary experiments via the World Wide Web.
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Bobushkina, S. V., A. O. Senkov,, and D. H. Fayzulin. "Practice on growing of forest containerized seedlings applicable to the greenhouse complexes of the Arkhangelsk region." FOREST SCIENCE ISSUES 4, no. 4 (December 30, 2020): 1–16. http://dx.doi.org/10.31509/2658-607x-2020-3-4-1-16.
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The need to develop and implement innovative forms of reforestation to obtain highly productive tree stands actualize the topic of the article. The purpose of the work is to study and analyze foreign experience and research on the production of softwood containerized planting stock for reforestation and compare it with the practice of greenhouse complexes in the Arkhangelsk region. We used the international bibliographic and abstract database «Scopus», which indexes scientific journals, materials from conferences and publications to search for information. A review of publications has been completed over more than a 20-year period (1999-2019). The world experience study and the results of studies on the cultivation of forest containerized seedlings, in particular, Finland, Sweden, Norway, countries similar in terms of the growth of woody vegetation and the range of tree species to the conditions of the European north of Russia made it possible to highlight current research directions. The treatment of seedlings with a short or long light day; frost resistance of the seedlings; influence of drought, excessive moisture; issues of seedling storage; diseases, pests of seedlings and control of them, as well as problems of selection and seed production; seed quality and their impact on plant growth; influence of cultivation technology and types of planting stock on the effectiveness of planting refers to them. The use of foreign plants for growing ball-rooted planting stock implies a similar technology for the production of forest seedlings in our region. However, climatic features and the availability of various consumables, such as peat, fertilizers, pesticides, etc., necessitate the adaptation of Scandinavian technologies to local conditions and the development of additional techniques. One of the main production tasks is the achievement of standard indicators by seedlings. It is not always possible to achieve the desired results in harsh taiga conditions, therefore it is necessary to use foreign experience in growing ball-rooted planting stock, which allows to increase the production of standard seedlings without compromising their quality. This is a whole range of measures, including work on breeding and seed production, the formation of a plant substrate, lighting, moisture, observing the temperature regime, storage of seedlings, combating diseases and pests, etc., which ultimately are the components of the success of artificial reforestation
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Murariu, Alin Constantin. "Improving the Fatigue Behaviour of PURMAL S-70 Polyurethane Paint." Solid State Phenomena 332 (May 30, 2022): 103–10. http://dx.doi.org/10.4028/p-6k8yey.
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Oxidation is one of the main degradation mechanisms that affects most industrial components and occurs as a result of a chemical reaction by which an oxygen atom is added to the molecule of an organic substance or compound. Light, in particular the ultraviolet (UV) component, activates the process of degradation of organic materials, favouring a series of oxidation reactions that occur when the component is in contact with oxygen in the air or water (especially salt water).Given that a number of components work in variable mechanical stress conditions (vibrations caused by the technological process itself or generated by repeated starts / shutdowns of equipment), the protective coatings aim to improve the physico-chemical properties of the surfaces to reduce the degradation, as well as to improve the fatigue behaviour, knowing that the fatigue cracks are initiated from local stress concentrators caused by the surface imperfections of the components. Paper presents the experimental results on fatigue behaviour of the deposited layers, after exposure to UV radiation. In the experimental program, a 2 mm thick AlMg3 sheet (EN AW-5754) was used as substrate. The Aluminium oxide layer naturally created on the metal surface, prevents the effect of oxygen and atmospheric pollutants, but this layer is unstable in corrosive environments. Thus, for a qualitative protection, protective organic layers are used. In experiments, the polyurethane paint PURMAL S 70, RAL 9010 (PUR) and the same paint but aditivate with graphene oxide (PUR + GO) were compared. Prior to fatigue testing, the painted specimens were subjected to accelerated artificial UV-aging process with ultraviolet radiation for 72 hours. Axial fatigue tests were performed with a frequency of 40 Hz, in pulsating mode, with R = 0.053 and with decreasing loads, starting from 0.85% of the tensile strength (Rm), up to 0.5% Rm. Analysis of S‑N curves revealed that, in the field of oligocyclic fatigue there are no significant differences between the fatigue results obtained on PUR-protected specimens, compared to those protected with PUR + GO, instead in the case of polycyclic fatigue, the paint with addition of 1% graphene oxide has improved fatigue resistance.
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GRANT, PETER M., and AMBER RYMER. "A simple, inexpensive artificial stream for rearing Ephemeroptera from sandy substrates." Zoosymposia 11 (November 18, 2016): 164–67. http://dx.doi.org/10.11646/zoosymposia.11.1.17.
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We describe a simple, inexpensive artificial stream to rear mayflies from sandy bottom streams. It consisted of a 151 L tub containing sand and water from a local stream. A small submersible pump circulated the water and netting was placed over the tub to collect adults. The stream was operated in a heated greenhouse. This artificial stream was remarkably productive. We collected over 2100 adult mayflies representing 6 genera along with several Trichoptera and Diptera adults. This stream was productive for 55 weeks with minimal maintenance.
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Mangelli, Tárcio Santos, and Joel Christopher Creed. "Análise comparativa da abundância do coral invasor Tubastraea spp: (Cnidaria, Anthozoa) em substratos naturais e artificiais na Ilha Grande, Rio de Janeiro, Brasil." Iheringia. Série Zoologia 102, no. 2 (June 2012): 122–30. http://dx.doi.org/10.1590/s0073-47212012000200002.
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Os corais exóticos coral-sol (Tubastraea coccinea Lesson, 1829 e T. tagusensis Wells, 1982) invadiram as comunidades biológicas sésseis dos costões rochosos da Baía da Ilha Grande, Rio de Janeiro, Brasil. Estruturas artificiais (piers, decks ou cais) foram selecionadas em quatro locais na Ilha Grande, e comparadas com substratos naturais adjacentes através de quantificação da densidade de cada espécie de Tubastraea, além da porcentagem de cobertura da biota bêntica. A densidade média geral de Tubastraea tagusensis foi de 80,3 indivíduos.m-2, aproximadamente o dobro encontrado para T. coccinea. Tendo em vista que sua presença alterou as abundâncias relativas e a riqueza de espécies, ambas as espécies invasoras modificaram a estrutura das comunidades invadidas. Tubastraea coccinea foi mais abundante em substratos artificiais do que naturais, porém, não foi detectada diferença na abundância de Tubastraea tagusensis entre substratos. A abundância de ambas as espécies variou com a profundidade e o local, e houve uma relação positiva entre a idade do substrato artificial e a abundância dos corais. Aparentemente T. tagusensis é competitivamente superior à T. coccinea, com uma inserção maior nas comunidades nativas em substratos naturais. Ambas as espécies tem grande potencial competitivo e podem utilizar substratos artificiais para iniciar seu estabelecimento em novos locais.
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Ushivtsev, V. B., S. V. Vostokov, L. I. Lobkovsky, N. B. Vodovsky, and M. L. Galaktionova. "Methodology of directional development of local biocenoses for optimization of monitoring and improvement of the marine environment on shelves of Russia." Доклады Академии наук 488, no. 1 (September 24, 2019): 94–98. http://dx.doi.org/10.31857/s0869-5652488194-98.
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The results of field experiments on the development of local biocenoses based on bottom bio-stations situated in areas with high anthropogenic influence in the Northern and Middle Caspian region are presented. Structural and functional parameters of local communities were studied in comparison with characteristics of background biocenoses. Biodiversity and informational content of local communities as objects of monitoring and bio indication was assessed. The application of the bottom biocenosis directed development on artificial substrates for monitoring and improvement of the marine environment are discussed.
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Borderie, Quentin, Rowena Banerjea, Stéphane Bonnet, Yannick Devos, Cristiano Nicosia, Christophe Petit, Ferréol Salomon, Nathalie Schneider, Barbora Wouters, and Patrice Wuscher. "Géoarchéologies des contextes urbains : mieux comprendre les modalités de l'artificialisation des géosystèmes." Archimède. Archéologie et histoire ancienne 7 (June 9, 2020): 141–57. http://dx.doi.org/10.47245/archimede.0007.act.04.
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L’objet des approches géoarchéologiques de l’urbain est constitué du site, de la ville en tant qu’artefact et bassin artificiel de sédimentation anthropique. Dans ces contextes, les relations entre les sociétés et le géosystème produisent des formations pédo-sédimentaires denses et diverses. Les échelles traitées sont celles d’un socio-système complexe, incluant le substrat pédo-géo-chimique local, les formations superficielles artificielles et les relations avec l’hinterland. Dans un contexte actuel d’artificialisation accéléré des espaces, comprendre ces systèmes peut être une clé pour aborder l’Anthropocène. Différentes approches géoarchéologiques de cet objet urbain hybride, conduites en Europe, sont exposées dans cet article. De l’âge du Fer à la période moderne, elles abordent les questions de topographie préurbaine, de gestion sociale des flux de matériaux, de pollutions, d’occupation des espaces et d’évolution des stratifications. Les résultats montrent la diversité des relations entre les sociétés et les sols, dans une co-construction sur le temps long de systèmes urbains artificiels.
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Smith, Stephen D. A., and Michael J. Rule. "Artificial substrata in a shallow sublittoral habitat: do they adequately represent natural habitats or the local species pool?" Journal of Experimental Marine Biology and Ecology 277, no. 1 (September 2002): 25–41. http://dx.doi.org/10.1016/s0022-0981(02)00242-3.
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Higgins, Emily, and Konstantin Sobolev. "Data-Driven Coral Reef Rehabilitation Using New Biomimicking, Advanced Materials Artificial Reefs." Marine Technology Society Journal 55, no. 3 (May 1, 2021): 120–21. http://dx.doi.org/10.4031/mtsj.55.3.13.
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Abstract Globally, artificial reefs (ARs) are being increasingly used as a coral reef restoration strategy, and ARs made from conventional substrates (e.g. metal, concrete) have had limited success for coral reef conservation due to structure size and lack of pre-deployment engineering. To curb further deterioration on reefs, technological advances in restoration methods must be quickly tested and applied on a large scale. Here, we present the results of the first IntelliReefs biomimicking “Oceanite” nanotechnology ARs. We compared benthic community composition on three Oceanite ARs 14 months after deployment in Sint Maarten. We also examined fish abundance, diversity, and behaviour on the ARs. The results from this study suggest that Oceanite can enhance local biodiversity, attract coral recruits, provide food and protection for large fish communities, and develop a healthy early coral reef community in 14 months. IntelliReefs' future research will focus on large-scale deployments and further development of site-, species-, and function-specific substrates to optimize AR conservation goals and increase project success. Our Ocean-Shot will deploy durable, bio-enhanced reefs that build resilience to climate change, increase economic benefits, and coastal protection for seaside communities. Oceanite can further be customized for specific stressor mitigation (e.g., pathogens, warming, acidification, reduced water quality, invasive species).
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Mavraki, Ninon, Steven Degraer, and Jan Vanaverbeke. "Offshore wind farms and the attraction–production hypothesis: insights from a combination of stomach content and stable isotope analyses." Hydrobiologia 848, no. 7 (March 1, 2021): 1639–57. http://dx.doi.org/10.1007/s10750-021-04553-6.
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AbstractOffshore wind farms (OWFs) act as artificial reefs, attracting high abundances of fish, which could potentially increase their local production. This study investigates the feeding ecology of fish species that abundantly occur at artificial habitats, such as OWFs, by examining the short- and the long-term dietary composition of five species: the benthopelagic Gadus morhua and Trisopterus luscus, the pelagic Scomber scombrus and Trachurus trachurus, and the benthic Myoxocephalus scorpioides. We conducted combined stomach content and stable isotope analyses to examine the short- and the time-integrated dietary composition, respectively. Our results indicated that benthopelagic and benthic species utilize artificial reefs, such as OWFs, as feeding grounds for a prolonged period, since both analyses indicated that they exploit fouling organisms occurring exclusively on artificial hard substrates. Trachurus trachurus only occasionally uses artificial reefs as oases of highly abundant resources. Scomber scombrus does not feed on fouling fauna and therefore its augmented presence in OWFs is probably related to reasons other than the enhanced food availability. The long-termed feeding preferences of benthic and benthopelagic species contribute to the hypothesis that the artificial reefs of OWFs could potentially increase the fish production in the area. However, this was not supported for the pelagic species.
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Varotto, Ricardo Silva, and Cristine Costa Barreto. "Colonization of artificial substrata by teredinid larvae released from a previously infested focus at Ilha Grande Bay, RJ." Brazilian Archives of Biology and Technology 41, no. 4 (August 1998): 391–400. http://dx.doi.org/10.1590/s1516-89131998000400002.
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The colonization pattern of wooden panels by teredinid larvae released from a previously infested focus was investigated. Panels were placed at different distances (1, 10, 20m) and in different directions from the focus. The colonization experiment took place at Parcel do Aleijado, Ilha Grande Bay, RJ. The focus remained immersed in nearly surface water, by the coast, during three months for infestation by teredinids. After this period, it was transferred to the study site. The infested focus and colonization panels remained in water, 10m deep, for three months more. Total density and density of the dominant species were considered for each group of panels. Five teredinid species were found: Bankia fimbriatula, Bankia gouldi, Lyrodus floridanus, Lyrodus massa and Teredo furcifera. The dominant species was Teredo furcifera (76.6%). Significant differences were only observed between directions for total teredinids and for dominant species density. Results concerning the dominant species Teredo furcifera were even more expressive and suggested the occurrence of a local water circulation pattern.