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The study was carried out from June 2021 to May 2022, to know the status and diversity of the Odonata (Dragonfly and Damselfly) fauna at Ecopark, West Bengal. They are essential for environmental monitoring and serve as biological indicators of the health of the ecosystem. During the study period, 34 species of odonates from 26 Genera and 5 Families were identified in the study area. Three families made up Suborder Anisoptera, while two families made up Suborder Zygoptera. Among them, 29 species of dragonflies belonged to the Aeshnidae, Gomphidae and Libellulidae families, while 11 species of damselflies belonged to the Coenagrionidae and Platycnemididae families. The family Libellulidae had the highest species composition (62%) followed by the family Coenagrionidae (29 %). Among all Odonates, 35% were very common (VC), 44% Common (C) 15% rare (R) and 6% were very rare (R) on the presence of their abundance. Such observation can provide insightful data on the status of Odonate populations in context to Rajarhat grassland. [ABSTRACT FROM AUTHOR]

New records of 43 species of dragonflies and damselflies from Trongsa and Zhemgang districts in central Bhutan are provided. Two of these, Watanabeopetalia atkinsoni (Selys, 1878) and Tetrathemis platyptera (Selys, 1878), are new to Bhutan bringing the number of species known from Bhutan to 125. A checklist of the 60 species known from Trongsa district, Zhemgang district and the Jigme Singye Wangchuck National Park is provided. [ABSTRACT FROM AUTHOR]

In recent years, the micro air vehicle (MAV) oscillations caused by thrust imbalances have received more attention. This paper proposes a dual-wing thrust balance model (DTBM) that can solve the above problem by iterating the modified rotation angle formula. The core control parameter of the DTBM model is the au angle, which refers to the angle between the wing surface and the stroke plane at the mid-stroke position during the upstroke. For each degree change in the au angle, the range of variation in the dimensionless average thrust coefficient is between 0.0225 and 0.0268. A thrust coefficient of 0.0225 causes the dragonfly to move forward by 9.037 cm in one second, which is equivalent to 1.29 times its body length. By using DTBM, the average thrust coefficient can be reduced to below 0.001 in just a few iterations. No matter how complex the motion pattern is, the DTBM can achieve thrust balance within 0.278 seconds. Through our research, when selecting the deviation angle motion of real dragonflies, the dual-wing au angles exhibit a highly linear correlation with wing spacing, called linear motion. In contrast, the nonlinear variation of the au angle appears in the hindwing of the no-deviation motion and the forewing of the elliptical deviation motion. All of the nonlinear changes are referred to as nonlinear motion. Nonlinear variation of the au angle arises from larger disturbances of the lateral force during the upstroke. The stronger lateral force is closely related to the flapping trajectory. When the flapping trajectory causes the dual-wing to closely approach each other in the mid-stroke, a continuous positive pressure zone forms between the dual-wing. The collision of the leading-edge vortex and the shedding of the trailing-edge vortex is the special flow field structure in the nonlinear motion. Guided by the DTBM, future designs of MAVs will be able to better achieve thrust balance during hovering flight, requiring only the embedding of the iteration algorithm and prediction function of the DTBM in the internal chip., (© 2024 IOP Publishing Ltd. All rights, including for text and data mining, AI training, and similar technologies, are reserved.)

Some visual neurons in the dragonfly ( Hemicordulia tau ) optic lobe respond to small, moving targets, likely underlying their fast pursuit of prey and conspecifics. In response to repetitive targets presented at short intervals, the spiking activity of these "small target motion detector" (STMD) neurons diminishes over time. Previous experiments limited this adaptation by including intertrial rest periods of varying durations. However, the characteristics of this effect have never been quantified. Here, using extracellular recording techniques lasting for several hours, we quantified both the spatial and temporal properties of STMD adaptation. We found that the time course of adaptation was variable across STMD units. In any one STMD, a repeated series led to more rapid adaptation, a minor accumulative effect more akin to habituation. Following an adapting stimulus, responses recovered quickly, though the rate of recovery decreased nonlinearly over time. We found that the region of adaptation is highly localized, with targets displaced by ∼2.5° eliciting a naive response. Higher frequencies of target stimulation converged to lower levels of sustained response activity. We determined that adaptation itself is a target-tuned property, not elicited by moving bars or luminance flicker. As STMD adaptation is a localized phenomenon, dependent on recent history, it is likely to play an important role in closed-loop behavior where a target is foveated in a localized region for extended periods of the pursuit duration ., Competing Interests: The authors declare no competing financial interests, (Copyright © 2024 Schwarz et al.)

Dragonflies are some of the most stable and maneuverable flying organisms. To explore the mechanism of how dragonfly leading edges enhance flight lift, this article conducts a detailed study on the leading edge veins and the microstructures on them of dragonfly wings. Observations have discovered the special leading edge vein and the regularly distributed microstructures on the leading edge vein. A biomimetic model has been established, and computational fluid dynamics (CFD) simulation analysis has been conducted on the biomimetic model. The analysis explores the effects of microstructure characteristics, distribution patterns, and positions on the aerodynamic characteristics of dragonfly gliding. The analysis shows that the leading edge structure influences the incoming flow, simultaneously promotes the formation of the leading edge vortex (LEV), and increases the lift-to-drag ratio by up to 4%. A wing prototype featuring biomimetic microstructures is subsequently fabricated and tested in wind tunnel experiments. Compared with a control group without leading edge structures, the airflow passing through the biomimetic structures is influenced by the shape and arrangement of these structures. The smoother transition of the leading edge vein's shape facilitates the flow of air. The microstructures primarily filter and accelerate the airflow. The spacing of the microstructures affects the stability of the airflow, thereby influencing aerodynamic performance. Additionally, the middle-row arrangement of microstructures is more beneficial for gliding conditions, while the upper-row arrangement is more advantageous for flapping conditions. These findings enhance our understanding of insect wings and advance micro aerial vehicle applications. RESEARCH HIGHLIGHTS: This study observed the leading-edge veins and microstructures of dragonfly wings in detail. Using a biomimetic model and computational fluid dynamics (CFD) simulations, it was found that these leading-edge structures promote the formation of leading-edge vortices (LEV), increasing the lift-to-drag ratio by up to 4%. Wind tunnel experiments demonstrated that wings with biomimetic microstructures significantly improved airflow smoothness and lift compared with control wings. Additionally, the arrangement of microstructures greatly affects airflow stability and aerodynamic performance, with middle-row arrangements being more beneficial for gliding and upper-row arrangements for flapping conditions. These findings enhance our understanding of insect wings and provide innovative guidance for designing efficient micro aerial vehicles., (© 2024 Wiley Periodicals LLC.)

The study of diversity and distribution of dragonfly, and their relationship with air parameters including temperature (°C) and humidity (%) at Sungai Muar, Kuala Pilah, Negeri Sembilan was carried out on 14 and 15 March 2020. The sampling of dragonfly was done in two parts of Sungai Muar, Kuala Pilah. For each site, the sampling was conducted in the morning and evening with the air temperature and humidity were recorded at the same time using hygrometer and digital thermometer clock humidity temperature HTC-1. Method that has been used for this study are net sweeping. The samples were collected, preserved and identified until species level. A total of 231 individuals were recorded with Ischnura elegans from Coenagrionidae family as a dominant species with 145 individuals, while the lowest abundance is Pseudagrionidae sp. of Coenagrionidae family with one individual only. For the relationship, there is no significant linear correlation between air parameters with individual number of dragonflies. As a recommendation, the other parameters including air and water parameters should be measured to increase our understanding on the abiotic parameters effects towards the survivability of dragonfly. This research give benefit to society and ecology where it provides knowledge and understanding about dragonfly species and the function of dragonfly as indication of environmental quality. Besides, this research can be used as guidelines for future research and update the checklist of dragonfly in Sungai Muar, Kuala Pilah.

The dragonfly Leucorrhinia pectoralis was recorded in Slovakia at 38 sites in 112 findings and there were 707 imagoes. Reproduction was confirmed in seven sites by finding of 35 larvae and exuviae. The highest number of sites with the occurrence of L. pectoralis is located in the Záhorská nížina lowland; most sites in Slovakia are located at an altitude of 213–351 m. L. pectoralis was recorded together with 49 species of dragonflies, and the average number of L. pectoralis was 9.56 individuals per site. It occurs in the communities as a dominant species (9.5%) together with eudominants Coenagrion puella, C. hastulatum and Libellula quadrimaculata. By non-metric multidimensional scaling (NMDS), we found a coenotic correlation to peat species Libellula quadrimaculata, Leucorrhinia rubicunda, L. dubia and Sympetrum danae. By redundancy linear analysis (RDA), we found a Monte Carlo permutation test to make a non-random contribution to the explained variability of seven factors (p = 0.012–0.034). L. pectoralis statistically significantly prefers habitats in the forest landscape (r = 0.62, p = 0.0063), the presence of vegetation (r = 0.94, p = 0.0003) and peatbogs (r = 0.61, p = 0.0058). We did not confirm a significant correlation to altitude. Based on easy determination, territoriality (especially males) and bioindicative sensitivity of larvae, L. pectoralis is accepted as an umbrella species. L. pectoralis has a high dispersion potential and is suitable for creating the meta-population character of local populations, which is important for the conservation management of the species.

In South Korea, both Sympetrum depressiusculum Sélys, 1841 (Odonata: Libellulidae), which is distributed throughout Europe and from Russia to the Korean Peninsula, and Sympetrum frequens Sélys, 1883, which is endemic to Japan, are recorded. However, the identity of South Korean populations and the validity of listing the two species have not yet been settled. In this study, we collected seventy-four individuals of Sympetrum species from South Korea (five localities), Russia, The Netherlands, and Japan. These samples were examined for morphology and sequenced for partial COI, 16S rRNA, and a nuclear internal spacer (ITS) region, after which these molecular data were combined with available public data from Russia, Japan, and The Netherlands. Major morphological characters that have been used to distinguish the two species and phylogenetic, network, and structure analyses all consistently suggest that South Korean populations form a single species. Consequently, it could be valid to treat South Korean populations as one species, S. depressiusculum, by applying the senior name. Nevertheless, the validity of maintaining each as an independent species in other countries may need additional study considering that our samples were focused more on South Korea and limited for Europe, Russia, and Japan.

Tropical mountains display limited variation in monthly temperatures, but high spatial climatic variability. It is assumed this stability promotes ecological and physiological adaptations to local temperatures, which may preclude dispersal up or downslope. Determining how environmental, taxonomic and morphological factors affect thermal limits is fundamental to understand biotic responses to global warming.We selected 54 species of dragonflies and damselflies (Order Odonata) distributed from 300 to 2,550 m along one of the most biodiverse regions on the planet, the Tatamá elevational gradient in the Andean‐Choco region transition. We estimated for 846 individuals three thermal tolerance parameters: CTmax, the highest temperature preceding the loss of motor control, Tvol, the temperature at which individuals avoid heat, and CTmin, the minimum temperature required for wing movement.For each thermal tolerance parameter, we evaluated associations between physiological and behavioural responses, species elevational distribution and specialization to forests or open areas. We also evaluated the effect of autecological characteristics such as body mass, sex and taxonomy on temperature regulation.Temperatures prevalent at different elevations and habitats are associated with odonate upper thermal limits. However, tolerance to low temperatures is not associated with habitat use or elevation. Forest species display lower thermal tolerances. Small species are more tolerant to high temperatures than larger species. Dragonflies are more tolerant to high temperatures than damselflies with similar body mass. Females are more tolerant to high temperatures than males.Our results highlight the importance of considering differences in morphology, life history and behaviour when comparing thermal tolerances of organisms along elevational gradients. Only by incorporating such factors, it would be possible to generate accurate predictions on the impact of climate change on tropical organisms. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

Congestion not only affects the power flow, but also leads certain issues, like market power, market inefficiency and security. When the transmission line exceeds their limits congestion is occurred (voltage, thermal, stability). Congestion management is a technique that helps to deal the issue corresponding to congestion. Many methods have been developed to manage congestion, and also several countries execute various strategies for the smooth functioning of their network. In this manuscript, the rescheduling of congestion management in a deregulated environment using DA-MRFO is proposed. The proposed hybrid technique is the combined execution of both the dragonfly algorithm (DA) and manta ray foraging optimization (MRFO). Dragonfly algorithm is enhanced using Manta ray Foraging optimization (MRFO), hence it is named DA-MRFO technique. The proposed method is used to alleviate transmission grid congestion on group-based electricity market via reprogramming active power of generators and also to reprogram the generator power. Congestion is the major Independent System Operator (ISO) concern on deregulated electricity market that is traditionally controlled by reprogramming generator output power. However, the effects of changes in the generator output power on the overloaded line flow are not identical. All the generators do not represent a desirable approach for congestion management. Here, a generator sensitivity factor is adapted for supporting the optimal generator selection in a congestion management (CM). In a congestion relief process, it is provided at the lowest possible cost. The reduction of power flow with collection of congested lines is probable through coordinated response of reactive energy dispatch as wind farms. The proposed approach is executed in modified IEEE 30 bus system and IEEE 57 bus system, then the efficiency is compared with the various existing optimization approaches. [ABSTRACT FROM AUTHOR]

Simple Summary: Bergmann's rule explains the phenomenon where populations and species of larger sizes are found at higher latitudes and colder environments, whereas populations and species of smaller size are found at lower latitudes and in warmer regions. In insects, adult sizes tend to be smaller in warmer environments than at cooler temperatures and higher latitudes; the response is called the temperature–size rule. Nannophya koreana is an endangered species in Korea and represents a flagship species for wetland conservation. We found that the body size of the larvae was smaller in a cold-water-temperature region than in a warm-water-temperature area, which is contrary to the rules mentioned above. The two regions were geographically close to each other, with no differences in air temperature and precipitation. We identified the reasons for the difference in water temperature between the two regions and established the relationship between temperature and body size in N. koreana. In addition, we analyzed how N. koreana compensated for low water temperature to maintain its life cycle, which is known as univoltine. Ecological rules such as Bergmann's rule and the temperature–size rule state that body-size decline is a universal response to warm temperatures in both homeotherms and poikilotherms. In the present study, we investigated the biological responses of Nannophya koreana, an endangered dragonfly species in Korea, by comparing body size in two habitats with large differences in water temperature, Mungyong-si (MG, terraced paddy fields) and Muui-do (MU, a mountainous wetland). To conserve the dragonfly populations, the collected larvae were photographed and released, and their head widths and body lengths were measured. There was no difference in the annual mean air temperature and precipitation between the two sites; however, the annual mean water temperature was substantially lower in MU than in MG. There was little difference in larval head width between the two sites; however, body length in the MU population was smaller than that in the MG population. Larval growth rate per 100-degree-days was 0.75 mm for MG and 1.16 for MU. The relationship between temperature and body size of N. koreana larvae showed opposite trends to Bergmann's rule and the temperature–size rule. Since the larval growth period during a year in MU was shorter than that in MG, the MU population potentially exhibits a higher growth rate as a mechanism of compensating for the low water temperature. Our study established the relationship between temperature and body size of N. koreana in two wetlands that had an obvious difference in water temperature despite being geographically close. The results highlight the importance of considering detailed factors such as habitat type when studying the temperature–size responses of organisms. [ABSTRACT FROM AUTHOR]

In dragonflies, species richness shows a marked variation between lineages. Species diversification in this lineage has been linked with habitat variation, but the role of other factors, such as wing pigmentation, arguably one of the most conspicuous traits in dragonflies, have not yet been explored.In this study, using novel methodology that takes into account state‐dependent speciation, extinction models, and ancestral reconstruction, we investigate the role of wing pigmentation (present/absent) in conjunction with habitat variation (lentic/lotic), to unveil the drivers of species diversification in dragonflies.We found that wing pigmentation is associated with a marginal increase in diversification compared to unpigmented lineages. Inhabiting a lentic habitat is associated with higher diversification rates. When considering both factors in a single model, lentic environments are associated with higher diversification compared to lotic habitats regardless of pigmentation status. In contrast with results across the whole tree, in lotic environments, wing pigmentation is associated with marginally higher diversification rates compared to non‐pigmented species. Ancestral state reconstruction revealed that the last common ancestor of dragonflies was most likely non‐pigmented and lived in lotic habitats.Our study provides evidence that wing pigmentation in conjunction with habitat has an important influence on dragonflies species diversification, with habitat being a better differentiator than wing pigmentation. [ABSTRACT FROM AUTHOR]

Nowadays, flexible alternating current transmission system devices, particularly unified power quality conditioner (UPQC) are found to have significant impacts on stability of rising power system. In power systems, several intellectual optimization methods were exploited to position the UPQC. However, those optimization models fail to offer more reliability and feedback signal. Hence, this paper presents a power quality improvement model, which is based on a hybrid algorithm that links genetic algorithm (GA) and DragonFly algorithm (DA). In the current research work, the optimal solution is determined based on the crossover operation of GA in dragonfly algorithm (DA), and hence, the adopted model is named as Genetically Modified DA algorithm. Moreover, the proposed model discovers the optimal location of UPQC device by focusing on the UPQC cost, power losses, and Voltage stability Index. The proposed model is carried out in IEEE 69, and IEEE 33 test bus systems. In addition, the performance of implemented model is distinguished over other conventional models such as artificial bee colony, firefly, grey wolf optimization, whale optimization algorithm, worst solution linked whale optimization algorithm update (WS-WU), GA and DA. The performance of the proposed model is effectively proved by performance and convergence analysis. [ABSTRACT FROM AUTHOR]

Farming expansion has negative impacts on freshwater biodiversity. However, the effects of agricultural land use are not similar across taxa and depend on local context. For instance, the impacts of agricultural expansion are understudied in the Neotropics (one of the leading regions in cropland expansion). Knowledge of the effects of agricultural land use on aquatic insects from South American subtropical grasslands (Pampa) is even more incipient. We tested whether landscape modification related to increased agricultural land use was associated with taxonomic homogenization in odonate communities in waterbodies in the Brazilian Pampa. Odonates were collected in waterbodies differing in the main land-use class in their surroundings (cropland or grassland). Cropland and grassland sites differed with respect to their abiotic conditions (water chemistry) and species composition of Odonata. Additionally, we found higher variation in the composition of Odonata (and suborders Anisoptera and Zygoptera separately) in grassland than cropland sites. We found an interplay between agricultural and grassland land uses and the variation in the composition of odonate communities in the Brazilian Pampa. Specifically, landscape modification by agriculture modified the abiotic conditions in the waterbodies, which may have favored species able to establish as larvae under harsher environmental conditions. Implications for insect conservation: We suggest that the maintenance of mixed-grassland and cropland land uses in the fields adjacent to waterbodies can limit the negative effects of agricultural encroachment on Odonata communities with respect to biotic homogenization in the Brazilian Pampa. [ABSTRACT FROM AUTHOR]

Amphithemis vacillans Selys, 1891 is reported for the first time from Meghalaya, Northeastern India. The authors recorded a male individual from the forest of Byrnihat, located in Ri-bhoi distict of the state on November 23, 2017. The current sighing revised the distribution of this species in India being previously known from Assam and West Bengal.

Rapid urbanisation is mainly responsible for the degradation and fragmentation of natural ecosystems in urban areas. Dragonflies and damselflies (Odonata) constitute an important part of urban biodiversity. The odonate larval stage is aquatic and being dependent on freshwater ecosystems, odonates are often used as ecological indicators for such ecosystems. Both larval and adult odonates are carnivorous and prey on other insects including mosquitoes. Hence, they perform an important role as predators in the ecosystems where they are found. In this study, the impact of a small artificial water source on the diversity of odonates in an urban landscape has been evaluated. The impact of the water source was found to be positive as its availability resulted in an increase in odonate diversity.

West Lombok District is the second largest district in Lombok Islands. The diversity of dragonflies (Order Odonata) as a bioindicator of environmental quality has not been widely studied in the West Lombok region. This study aimed to determine the species diversity of dragonflies (Order Odonata) found in Batubolong River, West Lombok District and its relation to the occurring land cover changes. This study was carried out by using a descriptive explorative method, where the sampling technique was done by means of line transects. Maps of study and sampling locations as well as land cover changes were made using ArcGIS 10.4.1 software based on primary and secondary data. The results showed that there were 11 species of dragonflies with a Shannon-Wiener diversity index value (H') of 2.212 (medium diversity), a population density index (C) of 0.126 (low dominance), and a species evenness index (E) of 0.923 (high uniformity). Our study also found two rare species of dragonfly in Lombok Island i.e., 3 individuals of Nososticta emphyla (Lieftinck, 1936) with 9% relative abundance and 1 individual of Drepanosticta berlandi (Lieftinck, 1939) with 3% relative abundance. The discovery of D. berlandi in Lombok is the third time after the findings in 1896 and the 19th century. Analysis of satellite data around the sampling area within the period 2013-2020 showed that there has been an increase in land cover of 6,149.29 m2. The increase in land cover changes may have caused the disappearance of several Odonata species in the sampling location.

• Bionic thin-walled tubes are designed inspired by dragonfly wings. • Parametric Analysis Inspired by Dragonfly Wings Morphology. • The theoretical model of bionic tube is established. • Bionic tube under multi-angle impact is optimized by NSGA-Ⅱ algorithm. Nature's creatures have developed remarkable geometric structures for environmental adaptation. Dragonflies have evolved a rapidly flipping symmetrical four-wing system to enhance hunting efficiency. Inspired by the unique double-symmetric wing structure of the dragonfly, a group of multi-cell elliptic tubes (METs) are developed to enhance the energy absorption capacity of thin-walled tube for multiple load cases. The finite element models of MET with different cross-sectional configurations are established and validated by quasi-static axial crushing tests. The crashworthiness of MET under different load angles θ have been explored and extensively studied by simulation method through LS-DYNA. The results indicate that the crashworthiness of MET could be influenced by the number of basic corner elements. Moreover, MET demonstrates higher energy absorption efficiency in oblique compression as compared to axial compression. Theoretical models of axial and oblique compressions are developed to predict the mean crushing force, which are obtained by summarizing the deformation modes of MET and employing simplified super folded unit theory. Finally, multi-objective particle optimization (MOPSO) algorithm is adopted to explore the MET crashworthiness optimization under oblique impact, with peak crushing force (PCF) and specific energy absorption (SEA) as targets and geometric parameters L, α, F and thickness t regarded as design variables. A new knee-point selection method is used to select MET from the pareto set of solutions of different schemes. The results show that different weight coefficients have great influences on the optimization results and further study is needed. [Display omitted] [ABSTRACT FROM AUTHOR]

Tool wear is an important concern in the manufacturing sector that leads to quality loss, lower productivity, and increased downtime. In recent years, there has been a rise in the popularity of implementing TCM systems using various signal processing methods and machine learning algorithms. In the present paper, the authors propose a TCM system that incorporates the Walsh–Hadamard transform for signal processing, DCGAN aims to circumvent the issue of the availability of limited experimental dataset, and the exploration of three machine learning models: support vector regression, gradient boosting regression, and recurrent neural network for tool wear prediction. The mean absolute error, mean square error and root mean square error are used to assess the prediction errors from three machine learning models. To identify these relevant features, three metaheuristic optimization feature selection algorithms, Dragonfly, Harris hawk, and Genetic algorithms, were explored, and prediction results were compared. The results show that the feature selected through Dragonfly algorithms exhibited the least MSE (0.03), RMSE (0.17), and MAE (0.14) with a recurrent neural network model. By identifying the tool wear patterns and predicting when maintenance is required, the proposed methodology could help manufacturing companies save money on repairs and replacements, as well as reduce overall production costs by minimizing downtime.

Research on the microbiomes of animals has increased substantially within the past decades. More recently, microbial analyses of aquatic invertebrates have become of increased interest. The storage method used while collecting aquatic invertebrates has not been standardized throughout the scientific community, and the effects of common storage methods on the microbial composition of the organism is unknown. Using crayfish and dragonfly nymphs collected from a natural pond and crayfish maintained in an aquarium, the effects of two common storage methods, preserving in 95% ethanol and freezing at −20 °C, on the invertebrate bacterial microbiome was evaluated. We found that the bacterial community was conserved for two sample types (gut and exoskeleton) of field-collected crayfish stored either in ethanol or frozen, as was the gut microbiome of aquarium crayfish. However, there were significant differences between the bacterial communities found on the exoskeleton of aquarium crayfish stored in ethanol compared to those that were frozen. Dragonfly nymphs showed significant differences in gut microbial composition between species, but the microbiome was conserved between storage methods. These results demonstrate that preserving field-collected specimens of aquatic invertebrates in 95% ethanol is likely to be a simple and effective sample preservation method for subsequent gut microbiome analysis but is less reliable for the external microbiome. [ABSTRACT FROM AUTHOR]

Human activities affect the structure, dynamics and energy flow of aquatic ecosystems. River damming, a common anthropic impact in Brazil, changes solar incidence, water flow and temperature of waterbodies, thereby affecting their fauna. Due to their high sensitivity to environmental changes, the Odonata may be indicators of these impacts. We sampled two ecologically distinct sites, (1) a quasi‐pristine forested area and (2) a nearby human‐impacted reservoir landscape, to evaluate the effects of damming on odonate community structure. The species composition of quasi‐pristine communities was more heterogeneous and differed almost completely (indicating high turnover) from that of the reservoir‐area communities. The capacity of the reservoir to maintain local fauna was almost nil. The communities in the changed landscape had the highest local diversity, which is related to the high occurrence of widespread generalist South American species. We also tested two recently proposed bioindication ratio tools based on the richness or abundance of high‐level taxonomic categories; both effectively reflected the extent of the impacts of damming. The best performing ratios were Coenagrionidae/other Zygoptera richness ratio, Zygoptera/Anisoptera abundance ratio and Libellulidae/other Anisoptera richness ratio. The reservoir landscape promotes biotic homogenization. However, the water supply system entails the preservation of part of the native habitat in its surrounding areas, consequently maintaining forest‐dependent biodiversity in quasi‐pristine environments. Practitioner points: The capacity of the reservoir (the damming process) to maintain quasi‐pristine forested communities was almost nil.The high diversity in the modified landscape (reservoir) is related to the high occurrence of widespread and generalist South American Odonata.Bioindication ratio tools were effective for demonstrating the extent of the impacts of damming. The best performing ratios were Coenagrionidae/other Zygoptera richness ratio, Zygoptera/Anisoptera abundance ratio and Libellulidae/other Anisoptera richness ratio. [ABSTRACT FROM AUTHOR]

The red swamp crayfish Procambarus clarkii (Cambaridae) has been introduced globally and has caused enormous biodiversity losses in freshwater ecosystems. Recently, this invasive species has been acknowledged as factor causing the decline of aquatic insect populations (Odonata, Hemiptera, and Coleoptera) in Japan. Although the negative impacts of P. clarkii on aquatic insect communities have been validated by observational studies and laboratory experiments, field studies have not yet been performed. In this study, we investigated whether the presence of P. clarkii was a significant factor influencing the community composition of aquatic insects and identified vulnerable taxa by comparing the aquatic insect communities in wetlands invaded by P. clarkii and uninvaded wetlands. We recorded a total of 52 species and 2721 individuals: 50 species and 2405 individuals in non-invaded wetlands, and 23 species and 316 individuals in invaded wetlands. This indicates that the aquatic insect diversity of non-invaded wetlands was higher than that of invaded wetlands. The composition of aquatic insect communities differed between the invaded and non-invaded wetlands. The effect of P. clarkii on aquatic insects differed according to their habit-related traits: species that utilize on the water surface and float near the water surface was less vulnerable than those that utilize aquatic plants as food, oviposition substrates, and perches and hide in the bottom substrate. The eradication of P. clarkii at the early stages of invasion, as well as the prevention of its spread in invaded ecosystems is essential to prevent negative impacts on aquatic insects. [ABSTRACT FROM AUTHOR]

Insects comprise over half of the described species, and the acquisition of metamorphosis must have contributed to their diversity and prosperity. The order Odonata (dragonflies and damselflies) is among the most-ancestral insects with drastic morphological changes upon metamorphosis, in which understanding of the molecular mechanisms will provide insight into the evolution of incomplete and complete metamorphosis in insects. In order to identify metamorphosis-related genes in Odonata, we performed comprehensive RNA-sequencing of the blue-tailed damselfly Ischnura senegalensis at different developmental stages. Comparative RNA-sequencing analyses between nymphs and adults identified eight nymph-specific and seven adult-specific transcripts. RNA interference (RNAi) of these candidate genes demonstrated that three transcription factors, Kr€uppel homolog 1 (Krh1), broad, and E93 play important roles in metamorphosis of both I. senegalensis and a phylogenetically distant dragonfly, Pseudothemis zonata. E93 is essential for adult morphogenesis, and RNAi of Kr-h1 induced precocious metamorphosis in epidermis via up-regulation of E93. Precocious metamorphosis was also induced by RNAi of the juvenile hormone receptor Methoprene-tolerant (Met), confirming that the regulation of metamorphosis by the MEKRE93 (Met-Kr-h1-E93) pathway is conserved across diverse insects including the basal insect lineage Odonata. Notably, RNAi of broad produced unique grayish pigmentation on the nymphal abdominal epidermis. Survey of downstream genes for Kr-h1, broad, and E93 uncovered that unlike other insects, broad regulates a substantial number of nymph-specific and adult-specific genes independently of Kr-h1 and E93. These findings highlight the importance of functional changes and rewiring of the transcription factors Kr-h1, broad, and E93 in the evolution of insect metamorphosis. [ABSTRACT FROM AUTHOR]

Odonates (Insecta: Odonata) are important insects in the food chains of freshwater environments around the world, being used as a model species for areas of behavior and analysis of environmental quality. In Brazil, especially in the Northeastern region, both knowledge about the distribution and molecular information of odonate species found in the two main biomes of the region is still limited. Aiming to improve these issues, here, we carried out an Odonata survey in two locations and built a DNA barcode database for species from the state of Paraíba. In total, 15 first records were reported for this Brazilian state and 142 specimens from 27 genera and 45 species had their 'Folmer' cytochrome c oxidase subunit I (COI) fragment evaluated. The database we generated includes data for 70% of the Odonata species found in Paraíba state. For 16 species, this is the first DNA barcode available in public sequence repositories. Our results demonstrate that using the COI in the regional scale can help identify and delimit those evaluated. Eight species (17%) showed a low percentage of differentiation (<2%) compared to other species currently deposited in the GenBank or BOLD System; nevertheless, we present morphological traits that reaffirm our identifications. Barcode data provide new insights into Neotropical diversity and deliver basic information for taxonomic analyses. [ABSTRACT FROM AUTHOR]

Metacommunity models describe species occupancy frequency distribution (hereinafter 'SOFD'). Our goal is to present how the differences in eight macroinvertebrate orders dispersal ability affect SOFD patterns. A total of 293 species from eight macroinvertebrate orders were observed in 14 eutrophic lakes in southern Finland. Species occupancy ranged from 1 to 14. About 30% (89 out of 293) of the species were found in only one lake, yielding a surprisingly high number of rare species. So, there were few widely distributed common species and numerous rare species with a restricted distribution. Combined data from eight macroinvertebrate orders supported the bimodal truncated SOFD pattern. Similarly, the low dispersal ability orders, watermites and mayflies, fitted the bimodal truncated SOFD pattern. However, bimodal symmetric SOFD pattern also fitted relatively well to the dragonflies and damselflies with high dispersal ability. It seems that differences in dispersal ability among different macroinvertebrate orders may partly explain observed differences. Moreover, our results supported slightly more a niche-based model rather than a metapopulation dynamics model in eutrophic lakes littoral macroinvertebrate metacommunities. Our results highlight that the dispersal ability is important trait for species conservation in patchily distributed habitat. [ABSTRACT FROM AUTHOR]

Dragonflies have excellent flight characteristics, which are inextricably related to the characteristics of their wings. Their wings not only support a variety of loads during flight but also maintain high‐efficiency flight characteristics. In this study, the forewing of a dragonfly (Pantala flavescens (Fabricius)) was used as a research object to explore the microstructure of the surface, cross section, and the vein distribution. Three‐dimensional models of three different structures of the forewing vein, including an oval‐shaped hollow tube, a circular hollow tube, and a circular solid tube, were established. Fluid dynamics analysis of these three forewing models under different angles of attack during gliding was carried out by FLUENT software, and subsequently, the influence of the dragonfly forewing vein structure on its flight characteristics was analyzed. The numerical simulation results indicated that the vein structure has a considerable influence on the lift, drag, and lift–drag ratio of the P. flavescens forewing. It was indicated that among the tested models, the forewing model with oval‐shaped hollow tubular veins has better flight efficiency and aerodynamic characteristics. The results of this study may provide the basis for a novel bionic concept of flapping wing microaircraft design. [ABSTRACT FROM AUTHOR]

The study of corrugated wings has become acquainted in the field of insect flight in recent times. Recent studies on the aerodynamic effects of a corrugated wing are based on insects like the Dragonfly; whereas the likes of Fruitfly (Drosophila Melanogaster) usually go unobserved due to their smaller size. Consequently, the behaviour of these corrugations is found to be anomalous especially in the low and ultra-low Reynolds number region. Therefore, the main aim of this study is to understand the aerodynamic effects of the corrugated airfoil present in the wing of a Fruitfly; by conducting a geometric parametric study during a static non-flapping flight at 1000 Re. In this computational study, a 2-D section of the corrugated wing along the chord is considered. The parametric study helps in understanding the effects of varying number of corrugations, angle of corrugations and the presence of a hump at the trailing edge. The dimensions were scaled to a suitable reference value to additionally compare the corrugated airfoil of Fruitfly to that of a Dragonfly. The present study shows that the aerodynamic performance of the corrugated wing in terms of cl and cd are predominantly governed by the subtle geometric variations that can largely impact the formation of bubbles, vortex zones, and their mutual interaction. The reduction in the number of leading edge corrugations improved the cl/cd ratio and reduction in the corrugation angle helped produce higher lift. The presence of a trailing edge hump also improved the stall angle with a better flow re-attachment. The presence of corrugation at the trailing edge proved to be more beneficial compared to the model with corrugations at the leading edge. This also helped in understanding, the aerodynamic superiority of the trailing edge corrugations present in the Dragonfly's wing when compared to the Fruitfly's.

The flying agility demonstrated by dragonflies is accomplished by means of complex aerodynamic forces produced by flapping their four wings arranged in a tandem configuration. The current study presents a novel tandem flapping wing mechanism for a biomimetic air vehicle that was designed and manufactured to experimentally investigate the aerodynamic forces. By optimizing the configuration and using spatial network analysis, it is shown that the designed structure can flap the wings in a linear up–down stroke motion and is capable of maintaining good consistency and aerodynamic performance. Such a mechanism could be used in a future biomimetic micro air vehicle (BMAV) design. The mechanism uses an electromagnetic actuator to flap the wings with a variable beat frequency (30–210 Hz) at various angles of attack (−10°–20°). The results show that the tandem wings generate approximately 50% higher lift than the forewing or hindwing pairs acting alone. Tandem wings also improve stability, which could potentially allow hovering.

This study presents a detailed analysis of dragonflies’ climbing flight by integratinghigh-speed photogrammetry, three-dimensional reconstruction, and computational fluid dynamics. In this study, a dragonfly’s climbing flight is captured by two high-speed cameras with orthogonal optical axes. Through feature point matching and three-dimensional reconstruction, the body kinematics and wing kinematics of 22 dragonflies in climbing flight are accurately captured. Experimental results show that the climbing angles (η) are distributed from 10° to 80° and are concentrated within two ranges, 60°–70° (36%) and 20°–30° (32%), which are defined as large angle climb (LAC) and small angle climb (SAC), respectively. In order to study the aerodynamic mechanism of the climbing flight based on the biological observation results, the kinematic parameters of the dragonfly during LAC and SAC are selected for analysis and numerical simulation. The results show that the climbing angle η and wing kinematics are related. There are considerable differences in wing kinematics during climbing with different η, while the wing kinematics are unchanged during climbing with similar η. With the increase in η, the phase difference (λ) between the forewing and the hind wing decreases and the amplitude of the positional angle (θmean) of the hind wing increases, while θmean of the forewing remains almost unchanged. Through numerical simulation of LAC and SAC, it can be found that during the climb with different η, the different wing kinematics have a significant influence on aerodynamic performance. During SAC, the increase in λ and the decrease in θmean of the hind wing weaken the aerodynamic disturbance of the forewing by the vortex wing of the hind wing, thus improving the flight efficiency.

Female mimicry by males is a widespread phenomenon in several taxa and may be involved in aggression avoidance or facilitated access to resources. In early developmental stages, female mimicry may be a mechanism involved in signalling sexual immaturity or, when coupled with strategies related to visual camouflage, may be involved in the avoidance of male-male agonistic interactions. Here, we addressed whether the delayed colour maturation of a sexual ornament in males of Mnesarete pudica damselflies might be a case of crypsis, female mimicry or both. We analysed how conspecifics and predators perceive the pigmented wings of juvenile males by contrasting the wing spectra against a savannah background and the wings of both juvenile and sexually mature males and females. Our results based on the modelled visual system of conspecifics and predators suggest that the colour maturation of juvenile males may function as both crypsis and female mimicry. We discuss whether these results related to age- and sexual-dichromatism might be a mechanism to avoid unwanted intraspecific interactions or to avoid territorial and aggressive males. We conclude that the female mimicry and crypsis in juvenile males of M. pudica are mechanisms involved in avoidance of predators and unwanted intraspecific interactions, and the signalling of sexual maturity. [ABSTRACT FROM AUTHOR]

The growth of agricultural and mining activities in the Amazon has impacted land-use and caused significant changes in the local environmental conditions of streams. In the face of these changes, our study aimed at assessing how environmental changes affect Odonata larval assemblages in streams in the eastern Amazon. We hypothesized that habitat conditions in streams are strong predictors of Odonata larval assemblages. We sampled 30 headwater streams (1st through 3rd order) in the eastern Amazon. We corroborated our hypothesis that regional- and local-scale environmental changes are important predictors of the Odonata larval assemblage structure. These results indicate that environmental conditions within the stream channel are important to maintain Odonata larval assemblages, as they provide important resources for larval development. For new studies, we recommend the assessment of temporal dynamics to evaluate whether these patterns are stable across time. Finally, evaluating various environmental scales of the original impact is extremely relevant for preventing the deterioration of or recuperating aquatic assemblages in Amazonian streams, considering the ongoing rapid environmental changes and deforestation in the region. Here we demonstrate that in-stream environmental conditions are important to assemblage structure and this must be considered in environmental restoration plans. [ABSTRACT FROM AUTHOR]

We compared the prevalence and intensity of Arrenurus sensu stricto water mite parasites on Enallagma civile Hagen in Selys, 1853 (Zygoptera: Coenagrionidae) from 10 freshwater wetlands (playas) in two different land-cover contexts in western Texas from 2006–2007. Vulnerability to parasitism may be a consequence of disturbance, so we predicted that the more natural form of regional land cover (grasslands) surrounding playas should be associated with a lower water mite load than more disturbed land cover (tilled croplands). Additionally, we examined Arrenurus occurrence and intensity of infection by host sex. Overall prevalence was 38.46% of 130 damselflies sampled having mites; this varied by land-cover type but with opposite trends between years. Overall average parasite load was ~11 water mites per infected host (range: 1–40 mites); intensity was significantly higher in hosts from cropland playas in 2006, but there was no difference by surrounding land cover in 2007. Although there were consistent trends in both years of more males being parasitized than females, the highly uneven distribution of parasites on hosts and differences in average mite load between years generated variability that obscured any statistically significant patterns. Thus, land-cover context surrounding playas, but not host sex, had an impact on parasite load in one of the two years of our study. Future work is needed to identify the mechanisms by which land cover may affect water mite-odonate host-parasite relationships as well as the role of the odonate assemblage as a whole in dispersal of parasites in a temporally dynamic wetland network. [ABSTRACT FROM AUTHOR]

Environmental management is one of the most important activities in ecological conservation at present. Faced with various socioeconomic impacts (e.g., urbanization, agriculture, and logging), practical and effective ways to analyze and determine how biodiversity is affected by these anthropogenic activities are essential. Utilizing niche theory helps to understand how similar groups of organisms respond to environmental changes based on the assumption that organisms with some niche overlap (i.e., similar resources) will respond similarly to these changes. Members of the order Odonata are frequently used as biological indicators due to their low survey costs, relatively easy taxonomic identification, and sensibility to environmental changes. In this study, using the PROTEST method, we analyze the cross-taxon congruence between Odonata and two aquatic organisms in Brazilian savanna streams: Gerromorpha and fishes. Although congruence was found between aquatic insects (~ 45%), this result changed when we only considered the species’ genera: no congruence for the aquatic insects was found, but instead we found a congruence between Odonata and fishes (~ 44%). Since Odonata showed congruence with the other groups in different taxonomical resolutions and it is a relatively easy and cheap group to collect and identify, we suggest that Odonata could be used as an indicator of disturbance for this set of organisms and hence serve as an alternative method to traditional environmental management techniques. [ABSTRACT FROM AUTHOR]

Anormogomphus heteropterus is redescribed based upon a single male specimen. Discrepancies and inaccuracies in previous illustrations of this species that could cause confusion are pointed out. Platygomphus benritarum sp. nov. is described on the basis of a single male specimen collected at Tezpur, Sonitpur District, Assam, India. Platygomphus benritarum differs from its congeners and other, similar species such as Asahinagomphus insolitus (Asahina, 1986) by its thoracic markings and shape of the abdomen and cerci. [ABSTRACT FROM AUTHOR]

Within wide geographical areas, Odonata populations can show biometric differences as a consequence of both biotic (e.g., predation, competition) and abiotic factors (mainly temperature). These differences can occur in the larval stage, although reliable characters are needed to detect differences. We analyzed whether Cordulegaster boltonii larvae from 18 Iberian populations differ regarding head width and prementum size (maximum width, minimum width, and maximum length), using measurements taken on final stage exuviae. Prementum length was greater in southern populations than in northern ones. Geographic latitude and temperature were the variables that best explained this variation in females, whereas latitude and altitude above sea level offered the best explanation among males. [ABSTRACT FROM AUTHOR]

Urbanization has considerable impacts on stream ecosystems. Streams in urban settings are affected by multiple stressors such as flow modifications and loss of riparian vegetation. The richness and abundance of aquatic insects, such as odonates, directly reflect these alterations and can be used to assess urban impacts on streams. The effects of urbanization on odonate richness and abundance on tropical islands is as yet poorly understood. The objective of this study is to identify the effects of urbanization on stream habitat quality and associated odonate assemblages in Puerto Rico. We sampled 16 streams along a rural to urban gradient in the San Juan Metropolitan Area, where each stream was characterized using the Stream Visual Assessment Protocol (SVAP) for Puerto Rico and by analyzing their surrounding land cover. A 100-m segment of each stream was surveyed to assess adult odonate richness and abundance during the rainy and dry seasons. Adults were identified visually, and their abundance was recorded. Favorable local scale factors, like improved habitat quality, as measured with the SVAP, resulted in higher abundances of odonates. However, regional factors such as percent urban cover did not appear to significantly affect richness and abundances of odonates. Overall, our study indicates that odonate assemblages are affected by the loss of habitat integrity, and conservation of tropical odonates may benefit from focusing on local scale factors. [ABSTRACT FROM AUTHOR]

In this study, computational fluid dynamics analysis was performed on a three-dimensional (3D) model of a Libellulidae wing to determine aerodynamic performance in gliding flight. The wing is comprised of various corrugated features alongside the spanwise and chordwise directions, as well as twist. The detailed features of real 3D dragonfly wing models, including all the corrugations through both span and chord, have not been considered in the past for a detailed aerodynamic analysis. The simulations were conducted by solving the Navier-Stokes equations to demonstrate gliding performance over a range of angles of attack at low Reynolds numbers. The numerical model was validated against experimental data obtained from a fabricated corrugated wing model using particle image velocimetry. The numerical results demonstrate that bio-inspired wings with corrugations compared to flat profile wings generate more lift with lower drag, trapping the vortices in the valleys of wing corrugation leading to delayed flow separation and delayed stall. The experimental and numerical results demonstrate that the methodology presented in this study can be used to measure bio-inspired 3D wing flow characteristics, including the influence of complex corrugations on aerodynamic performance. These findings contribute to the advancement of knowledge required for designing an optimized bio-inspired micro-air vehicle. [ABSTRACT FROM AUTHOR]

Rice paddy fields are important habitat for many dragonfly species. In Japan, populations of dragonflies inhabiting rice paddies, in particular Sympetrum (Odonata: Libellulidae), have decreased greatly in the last few decades. A major cause of the decline has been suggested to be the use of systemic insecticides (e.g., phenylpyrazole and neonicotinoid) in nursery boxes of rice seedlings. In this study, we examined the effects of chlorantraniliprole (CAP), a novel anthranilic diamide insecticide, on adult emergence of Sympetrum dragonflies in ten rice paddy fields by counting their exuviae remaining on the rice plants as an abundance index. Our results suggest that CAP is a potential factor that reduced the emergence rate of S. infuscatum but not of S. frequens. This difference may be due to differential sensitivity to CAP, different lengths of the nymphal stage, or different effects of bottom-up controls via reduction of prey organisms that are highly sensitive to CAP. [ABSTRACT FROM AUTHOR]

In this communication, we have collated a checklist of 97 species of odonates from Doon valley, Uttarakhand by reviewing the literature. These species are distributed across 13 families, 58 genera, and eight superfamilies. Of these species, 60 were Anisoptera (dragonflies) and 37 were Zygoptera (damselflies). Three species of dragonflies and two damselflies are endemic to India. This checklist updates existing knowledge on insect diversity in the Doon valley and will aid conservation management of wetlands in the region. [ABSTRACT FROM AUTHOR]

The inventory-production system concerns the effective management of the goods flows from raw materials to finished products. The Integrated Procurement-Production (IPP) system consists of many elements that must be managed effectively. The problem will be more complex if it involves deciding on the number of delivery frequencies at the retailer level. In this case, the Integrated Procurement-Production's objective function depends on the frequency of raw material shipments, the frequency of delivery of finished products, and the time of the production cycle. This study aims to develop an IPP system to maximize total profit. The decision variables used are the frequency of raw material delivery, the frequency of delivery of finished products, and the production cycle time. This study proposes the Dragonfly Algorithm (DA) as an algorithm for problem-solving. Dragonfly Algorithm is used to find the best inventory decision variables. This study conducted experiments with various iteration parameters and DA population. The results showed that the greater the iteration and the population used, the greater the profit. A sensitivity analysis of decision variables is also presented in this investigation.

Abstract This paper investigates species richness and species occupancy frequency distributions (SOFD) as well as patterns of abundance–occupancy relationship (SAOR) in Odonata (dragonflies and damselflies) in a subtropical area. A total of 82 species and 1983 individuals were noted from 73 permanent and temporal water bodies (lakes and ponds) in the Pampa biome in southern Brazil. Odonate species occupancy ranged from 1 to 54. There were few widely distributed generalist species and several specialist species with a restricted distribution. About 70% of the species occurred in

Climate change and an ever-increasing effect of humans on the great majority of freshwater ecosystems have affected not only individual organisms but also the links between them. In order to effectively protect communities or entire freshwater ecosystems, we need to understand how individual organisms react to these changes and the functional interconnections between individual species. This can be achieved by evaluating the functioning of individual species, i.e. their traits. Dragonflies and damselflies are increasingly used as indicators of changes in freshwater ecosystems. Although this taxonomic group is the subject of many ecological studies, there is no comprehensive database of the traits of European species. This is, why we decided to lay the foundations for an European database of dragonfly traits called dragonfly-database.eu, which is mainly based on Web of Science (WOS) publications and several monographs, and currently includes information on 79 European species. The main advantage of our database is that it is open to downloading, uploading, and storing of data. This is extremely important, because a database's applicability increases with the quality of the data it contains. Initially in compiling the database, we encountered several fundamental shortcomings in the knowledge of some often easily measurable traits in, some species. We believe that in combination with new statistical methods dragonfly-database.eu will become a very useful tool for many ecological studies and more effective conservation of threatened species.

Previously, a total of 57 species of Odonata were reported from the Asansol-Durgapur Industrial Area, India. In this present attempt the author reports an additional six species occurring from the same region. Among six of the species were found between January 2016 and September 2019, with one of them belonging to the Aeshnidae family, two to the Gomphidae family, two to the Libellulidae family, and only one damselfly from the Lestidae family. The species Gomphidia leonorae Mitra, 1994 has been reported in this paper for the second time from West Bengal, India, after a gap of 23 years, from Durgapur Barrage, which is situated at the end point of the study area.

The yellow-winged darter (Sympetrum flaveolum Linnaeus, 1758, Odonata), which is associated with high mountain areas, can be considered a flagship species. Due to climate change, its natural range will be negatively affected. In this study, we propose global potential distributions for this species up to the year 2100, considering four time periods (2021–2040, 2041–2060, 2061–2080, and 2081–2100) and three shared socioeconomic pathways (optimistic—SSP245, middle of the road—SSP370, and worst—SSP585), by using an ecological niche model to produce two sets of distribution models (80% to 100% and 60% to 100%). It is foreseen that in the worst of the considered climate scenario (SSP585– 2100 year), the distribution of this species could be reduced by almost half, which could pose a risk for the species and provoke the shift from vulnerable to endangered. An analysis of connectivity has also been carried out for all the studied scenarios by applying the MSPA and PC indices, showing that the core habitat of this species will become more important, which is consistent with the decrease in the distribution range. Over time, the importance of the most valuable connectors will increase, implying a greater risk of some populations becoming isolated.