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1.
Braz. j. biol ; 83: e251958, 2023. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1339380

RESUMO

Abstract Odonates are important biological control agents for the control of insect pests and insect disease vectors of medical and veterinary importance. The present study was conducted to evaluate the odonate fauna of Swat, Pakistan from March to October 2019. A total of 200 specimens of odonates were collected from diverse habitats. The collected specimens of the order Odonata belonged to 5 families, three families of suborder Anisoptera namely Libellulidae, Gomphidae and Aeshnidae while two families of suborder Zygoptera (Chlorocyphidae and Coenagrionidae). The specimens were categorized into 12 genera and 22 species. Libellulidae was the dominant family (n = 138) accounting for 69% of the odonate fauna. Orthetrum was the dominant genus (n = 73) of suborder Anisoptera accounting for 36.5% of the odonate fauna. The least dominant genera were Anax, Paragomphus and Rhyothemis (n = 5 each) accounting each for 2.5% of the odonate fauna. In Zygoptera, the dominant genus was Ceriagrion (12.5%) and the least dominant genus was Ischnura (6%). Pantala flavescens (Fabricius, 1798) was the most abundant odonate species in the study area recorded from all surveyed habitats. Shannon Diversity Index (H) was 2.988 and Simpson Diversity Index (D) was 0.95 for the collected odonate fauna. The highest abundance of Odonata was recorded in August, September and May while no odonate species were recorded in January, February, November and December. Lotic water bodies were the most suitable habitats with abundant odonate fauna. Anax immaculifrons (Rambur, 1842) was the largest sized odonate species having a wingspan of 53.2±1.63 mm and body length of 56.3 ± 0.4 mm. The present study shows the status of odonate fauna of Swat, Pakistan in diverse habitats and seasonsonal variation throughout the year. Further work is recommended to bridge the gaps in the existing literature.


Resumo Odonatos são importantes agentes de controle biológico para o controle de insetos-praga e vetores de doenças de insetos de importância médica e veterinária. O presente estudo foi conduzido para avaliar a fauna de odonatos de Swat, Paquistão, de março a outubro de 2019. Um total de 200 espécimes de odonatos foi coletado em diversos habitats. Os espécimes coletados da ordem Odonata pertenciam a cinco famílias, três famílias da subordem Anisoptera, a saber, Libellulidae, Gomphidae e Aeshnidae, enquanto duas famílias eram da subordem Zygoptera (Chlorocyphidae e Coenagrionidae). Os espécimes foram classificados em 12 gêneros e 22 espécies. Libellulidae foi a família dominante (n = 138), respondendo por 69% da fauna de odonatos. Orthetrum foi o gênero dominante (n = 73) da subordem Anisoptera, responsável por 36,5% da fauna de odonatos. Os gêneros menos dominantes foram Anax, Paragomphus e Rhyothemis (n = 5 cada), representando cada um 2,5% da fauna de odonatos. Em Zygoptera, o gênero dominante foi Ceriagrion (12,5%), e o gênero menos dominante foi Ischnura (6%). Pantala flavescens (Fabricius, 1798) foi a espécie de odonato mais abundante na área de estudo, registrada em todos os habitats pesquisados. O Índice de Diversidade de Shannon (H) foi de 2,988, e o Índice de Diversidade de Simpson (D) foi de 0,95 para a fauna de odonatos coletados. A maior abundância de Odonata foi registrada em agosto, setembro e maio, enquanto nenhuma espécie de Odonata foi registrada em janeiro, fevereiro, novembro e dezembro. Corpos d'água lóticos foram os habitats mais adequados, com abundante fauna de odonatos. Anax imaculifrons (Rambur, 1842) foi a espécie de odonato de maior tamanho, com envergadura de 53,2 ± 1,63 mm e comprimento do corpo de 56,3 ± 0,4 mm. O presente estudo mostrou o status da fauna de odonatos de Swat, Paquistão, em diversos habitats e variação sazonal ao longo do ano. Recomenda-se trabalho adicional para preencher as lacunas na literatura existente.


Assuntos
Animais , Odonatos , Paquistão
2.
Sci Total Environ ; 855: 158829, 2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36116637

RESUMO

The integration of life-history, physiological and behavioural traits into the pace-of-life generates a powerful framework to understand trait variation in nature both along environmental gradients and in response to environmental stressors. While the gut microbiome has been hypothesized as a candidate mechanism to underlie differentiation in the pace-of-life, this has been rarely studied. We investigated the role of the gut microbiome in contributing to the differentiation in pace-of-life and in thermal adaptation between populations of Ischnura elegans damselfly larvae inhabiting warmer low latitudes and colder high latitudes. We carried out a common-garden experiment, whereby we manipulated the exposure of the damselfly larvae to two key global warming factors: 4 °C warming and a 30 °C heat wave. Comparing the bacterial composition of the food source and the bacterioplankton indicated that damselfly larvae differentially take up bacteria from the surrounding environment and have a resident and functionally relevant microbiome. The gut microbiome differed between larvae of both latitudes, and this was associated with the host's latitudinal differentiation in activity, a key pace-of-life trait. Under heat wave exposure, the gut microbial community composition of high-latitude larvae converged towards that of the low-latitude larvae, with an increase in bacteria that likely are important in providing energy to cope with the heat wave. This suggests an adaptive latitude-specific shift in the gut microbiota matching the better ability of low-latitude hosts to deal with heat extremes. In general, our study provides evidence for the gut microbiome contributing to latitudinal differentiation in both the pace-of-life and in heat adaptation in natural populations.


Assuntos
Microbioma Gastrointestinal , Odonatos , Animais , Odonatos/fisiologia , Aquecimento Global , Larva , Temperatura Alta , Bactérias
3.
Environ Pollut ; 315: 120349, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36206892

RESUMO

Road deicing salts are frequently used in northern regions of the world during the winter and early spring months. As a result, a significant portion of road runoff into surrounding aquatic habitats contains road deicing salts. Previous studies found road salt contaminations in vernal pools that pond-breeding amphibians commonly use, including spotted salamanders (Ambystoma maculatum) and wood frogs (Lithobates sylvaticus). Studies have examined the impact of road salt on both amphibian species, but to our knowledge no previous studies have examined how road salt impacts the interspecific competition between both amphibians. We hypothesized that road salt would negatively impact growth and survivorship of both amphibian species. During the spring and summer of 2017, we conducted an outdoor mesocosm experiment in which we created eight experimental conditions with three main factors: presence/absence of NaCl (1000 mg/L Cl-), presence/absence of interspecific competition between the two amphibian species (A. maculatum and L. sylvaticus), and presence/absence of predatory dragonfly larvae (Family Libellulidae). Our experiment revealed that salt delayed hatching and increased deformity in spotted salamander hatchlings. Additionally, salt reduced salamander survivorship by 62% and frog survivorship by 30%. Wood frog tadpoles and road salt interacted to diminish salamander survivorship a further 80% beyond salt alone, likely through an increase in interspecific competition. Road salt increased the larval period of salamanders and decreased the proportion metamorphosed by the end of the experiment. Dragonfly larvae reduced salamander survivorship by 35%, whereas they increased wood frog tadpole development rates. Dragonfly larvae and salt interacted to alter tadpole denticle size, with salt negating the impact of dragonfly larvae. Thus, we found that salt interfered with aquatic predatory chemical cues. Overall, the results of this study suggest that management strategies should be implemented in order to reduce the impact of road salts on freshwater aquatic ecosystems.


Assuntos
Ambystoma , Odonatos , Animais , Cloreto de Sódio/farmacologia , Comportamento Predatório , Ecossistema , Sais , Ranidae , Larva , Urodelos
4.
Sci Rep ; 12(1): 17324, 2022 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-36243749

RESUMO

Differences in hatching dates can shape intraspecific interactions through size-mediated priority effects (SMPE), a phenomenon where bigger, early hatched individuals gain advantage over smaller, late hatched ones. However, it remains unclear to what extent and how SMPE are affected by key environmental factors such as warming and predation risk imposed by top predators. We studied effects of warming (low and high temperature) and predation risk (presence and absence of predator cues of perch) on SMPE in life history and physiological traits in the cannibalistic damselfly Ischnura elegans. We induced SMPE in the laboratory by manipulating hatching dates, creating following groups: early and late hatchlings reared in separate containers, and mixed phenology groups where early and late hatchlings shared the same containers. We found strong SMPE for survival and emergence success, with the highest values in early larvae of mixed phenology groups and the lowest values in late larvae of mixed phenology groups. Neither temperature nor predator cues affected SMPE for these two traits. The other life history traits (development rate and mass at emergence) did not show SMPE, but were affected by temperature and predator cues. A tendency for SMPE was found for protein content, in the high temperature treatment. The other physiological traits (phenoloxidase activity and fat content) showed fixed expressions across treatments, indicating decoupling between physiology and life history. The results underline that SMPEs are trait-dependent, and only weakly or not affected by temperature and predation risk.


Assuntos
Odonatos , Comportamento Predatório , Animais , Canibalismo , Larva/fisiologia , Monofenol Mono-Oxigenase , Odonatos/fisiologia
5.
Zootaxa ; 5138(1): 54-66, 2022 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-36101038

RESUMO

Telebasis Selys, 1865 is a genus well represented in Colombia, with 18 species distributed throughout the territory, one of them being endemic to the country. One of the most underexplored biogeographic regions of the country is the Choc, where we found the two new endemic species of Telebasis here described, Telebasis blasi sp. nov. and Telebasis noveloi sp. nov. In the description of both species, we provide detailed information about their distribution, diagnostic characteristics for males and females, pictures of living specimens and diagnostic characteristics, and a map showing the localities where each species was found. Finally, remarks on the conservation status of these species are presented; we consider that they are probably endangered, since they occupy small ranges and are threatened by several human activities.


Assuntos
Odonatos , Animais , Colômbia , Feminino , Humanos , Masculino
6.
Zootaxa ; 5134(4): 504-520, 2022 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-36101052

RESUMO

The larval characters of the genus Indocnemis Laidlaw, 1917 are described based on larval specimens of I. orang (Frster in Laidlaw, 1907) from Thailand. The larvae are characterized by 56 pairs of premental setae, 89 palpal setae of the same length, and vertical lamella caudal gills. The habitats and new provincial records of I. orang in Thailand are also provided in addition to a key to the genera of the family Platycnemididae in Asia.


Assuntos
Odonatos , Animais , Ecossistema , Larva , Tailândia
7.
Zootaxa ; 5134(3): 441-447, 2022 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-36101055

RESUMO

The final instar larva of the genus Archineura Kirby, 1894 is described for the first time, based on a specimen of the Chinese endemic species Archineura incarnata (Karsch, 1892) collected from Mt. Nankunshan, Guangdong Province, China. The larva is distinguished by several characters, including its moderately slender build combined with the distinctive extremely long legs, long, narrow, uniquely spined outer caudal appendages, a mask strongly expanded anteriorly with a relatively small median cleft, and robust spines at the apex of the labial palp. The mask is most similar to larvae of Echo Selys, 1853, Mnais Selys, 1853 and Psolodesmus MacLachlan, 1870 which are considered its nearest relatives based on molecular analysis, but from which it differs in other characters. The biology of Archineura larvae is discussed briefly.


Assuntos
Odonatos , Animais , Biologia , Larva
8.
Zootaxa ; 5134(3): 426-434, 2022 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-36101057

RESUMO

The final stadium larvae of Huosoma latiloba (Yu, Yang Bu, 2008) and Huosoma tinctipenne (McLachlan, 1894) from Yunnan Province, China are described and illustrated for the first time, with diagnostic differences between the two species identified. While no morphological characters separating the adults of this genus, and the closely related western Palaearctic Pyrrhosoma Charpentier, 1840 have been found, the larvae of these two genera do show differences which are discussed here.


Assuntos
Galliformes , Odonatos , Animais , China , Larva/anatomia & histologia
9.
Zootaxa ; 5133(3): 413-430, 2022 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-36101091

RESUMO

We describe a new species of dragonfly, Burmagomphus chaukulensis sp. nov., based on four males and two females from Chaukul, Sindhudurg, Maharashtra located in the Western Ghats biodiversity hotspot of India. The newly described species is diagnosed from its congeners by a combination of following characters: the shape of male caudal appendages (prominent lateral spines on cerci) and the lateral thoracic markings (stripe on mesepisternum reduced and pointed anteriorly). Additionally, B. chaukulensis is unique in terms of the shape of hamuli, strongly angulated with spines at both sides. An updated identification key to Indian Burmagomphus spp. is also provided.


Assuntos
Dipterocarpaceae , Odonatos , Animais , Tamanho Corporal , Feminino , Índia , Masculino
10.
Zootaxa ; 5133(3): 346-354, 2022 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-36101095

RESUMO

Macromia siamensis sp. nov., is described and illustrated based on male specimens collected from Ban Luang, Chom Thong, Chiang Mai province, Thailand. Macromia siamensis sp. nov. shares the hammer-shaped tip of posterior hamulus with M. amphigena Selys, 1871, M. sombui Vick, 1988, M. cydippe Laidlaw, 1922, M. vangviengensis Yokoi et Mitamura, 2002, M. clio Ris, 1916, M. malleifera Lieftinck, 1955, and M. macula Zhou, Wang, Shuai Liu, 1994, but it differs from all of the mentioned species by a set of coloration characters including antehumeral stripe, abdominal pattern and facial markings.


Assuntos
Dipterocarpaceae , Odonatos , Animais , Masculino , Tailândia
11.
Zootaxa ; 5125(2): 182-204, 2022 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-36101220

RESUMO

Taxonomy of the genus Cordulegaster Leach in Brewster, 1815 in Greece is not completely understood. The taxonomic status of the subspecies C. helladica buchholzi (Lohmann, 1993), C. helladica kastalia (Lohmann, 1993), and C. heros pelionensis Theischinger, 1979 was still unclear. We applied a molecular genetic approach using sequences of mitochondrial and nuclear DNA fragmentscytochrome c oxidase I (COI) and Internal Transcribed Spacer 1 (ITS1). This approach revealed that specimens presently assigned to C. heros pelionensis should be considered as conspecific to the nominate subspecific taxon making C. heros a monotypic species. Two major monophyletic lines were found within the Greek representatives of the species grouped around C. bidentata Selys, 1843: the clade of the European endemic C. bidentata and the clade composed of three species: C. helladica (Lohmann, 1993), C. buchholzi (stat. nov., raised to species level), and C. insignis Schneider, 1845. Cordulegaster helladica is restricted to the Peloponnese. Cordulegaster buchholzi is not restricted to the Cyclades as previously thought, but widespread from the Cyclades over the island Euboea to south-east mainland Greece reaching in the west near Mount Parnassos, where it hybridize with C. bidentata. Hybridization between C. bidentata and C. buchholzi was detected at the Castalian Spring, where in ancient times the Oracle of Delphi was located, and some kilometres east of the Castalian Spring. These hybrids had been formerly named C. helladica kastalia. In the case of C. insignis montandoni St. Quentin, 1971 we have investigated specimens some kilometres away from the type locality in Romania, which all revealed hybrids between C. bidentata and C. insignis. However, we do not know if specimens phenotypically looking like C. insignis from further west in the SE Balkans represent isolated population of C. insignis within the range of C. bidentata or belong to a broader hybrid zone between C. bidentata and C. insignis.


Assuntos
Dipterocarpaceae , Odonatos , Animais , Grécia , Filogenia
12.
Philos Trans R Soc Lond B Biol Sci ; 377(1862): 20210279, 2022 10 24.
Artigo em Inglês | MEDLINE | ID: mdl-36058235

RESUMO

Visual opsins of vertebrates and invertebrates diversified independently and converged to detect ultraviolet to long wavelengths (LW) of green or red light. In both groups, colour vision largely derives from opsin number, expression patterns and changes in amino acids interacting with the chromophore. Functional insights regarding invertebrate opsin evolution have lagged behind those for vertebrates because of the disparity in genomic resources and the lack of robust in vitro systems to characterize spectral sensitivities. Here, we review bioinformatic approaches to identify and model functional variation in opsins as well as recently developed assays to measure spectral phenotypes. In particular, we discuss how transgenic lines, cAMP-spectroscopy and sensitive heterologous expression platforms are starting to decouple genotype-phenotype relationships of LW opsins to complement the classical physiological-behavioural-phylogenetic toolbox of invertebrate visual sensory studies. We illustrate the use of one heterologous method by characterizing novel LW Gq opsins from 10 species, including diurnal and nocturnal Lepidoptera, a terrestrial dragonfly and an aquatic crustacean, expressing them in HEK293T cells, and showing that their maximum absorbance spectra (λmax) range from 518 to 611 nm. We discuss the advantages of molecular approaches for arthropods with complications such as restricted availability, lateral filters, specialized photochemistry and/or electrophysiological constraints. This article is part of the theme issue 'Understanding colour vision: molecular, physiological, neuronal and behavioural studies in arthropods'.


Assuntos
Artrópodes , Odonatos , Sequência de Aminoácidos , Animais , Artrópodes/genética , Evolução Molecular , Células HEK293 , Humanos , Invertebrados , Opsinas/genética , Filogenia , Vertebrados
13.
Zootaxa ; 5165(2): 287-293, 2022 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-36095467

RESUMO

A new species of the Neotropical dragonfly genus Gomphoides Selys, 1854 (Odonata: Gomphidae) is erected from the Cerrado of central Brazil, distinguished by epiproct morphology, body coloration and wing venation. Gomphoides davi Datto-Liberato Guillermo-Ferreira sp. nov. resembles G. perdita (Frster, 1914), but is distinguished from it by the S10 black, while it is yellow in G. perdita; four cells in the subtriangle of Fw while there are three cells in G. perdita and epiproct shorter than half of the length of cerci while epiproct is more than half the length of the cerci in G. perdita. We also provide additional information for other Gomphoides species. The discovery of a new species in the Environmental Protection Area of the Uberaba River, Minas Gerais, raises concern for the conservation of the biodiversity of the area, mainly because of recent threats due to cattle herding and agriculture.


Assuntos
Odonatos , Agricultura , Animais , Abelhas , Brasil , Bovinos , Conservação dos Recursos Naturais , Rios
14.
Zootaxa ; 5154(3): 289-304, 2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-36095621

RESUMO

In this seventh part of this series, 8 new species of Eupithecia Curtis, 1825 are described from China: Eupithecia prochazkai sp. n., Eupithecia anickae sp. n., Eupithecia divertenta sp. n., Eupithecia saldaitisi sp. n., Eupithecia ludificata sp. n., Eupithecia butvilai sp. n., Eupithecia ursina sp. n. and Eupithecia nesciaria sp. n. Three previously described species are recorded in China for the first time: Eupithecia oxycedrata (Rambur, 1833), Eupithecia phulchokiana Herbulot, 1984, and a range extension is given for a fourth, Eupithecia pannosa Mironov Galsworthy, 2008, and Eupithecia matrona Mironov Galsworthy, 2004. Adults and genitalia are illustrated for all species.


Assuntos
Mariposas , Odonatos , Animais , China , Genitália
15.
Zootaxa ; 5182(3): 279-287, 2022 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-36095685

RESUMO

The larva of Miocora aurea (Ris, 1918) was found in first and second order forested streams at the Tatam National Park in the Colombian Western Andes. Here it is described and figured the final larval stadium. It differs from the larva of M. chirripa (Calvert, 1917) by a combination of features such as antennal pedicel (0.25x longer than 3rd antennomere), prementum (0.20x longer than its widest part), and posterior margin of tergite 10 with a moderate incision.


Assuntos
Odonatos , Animais , Florestas , Larva , Parques Recreativos , Rios
16.
Zootaxa ; 5178(5): 493-500, 2022 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-36095714

RESUMO

Heteragrion roquei sp. nov. (Brazil, Bahia state, Municipality of Una, Fazenda Araruna, (-15.3146, -39.1621), 40 m, 19.ix.2019, M.E. Rodrigues leg., UESC) is described based on two males recently collected in Bahia state, Brazil. The new species is illustrated, diagnosed and compared with morphologically close congeners, being separated from them mainly by cercus characters, such as the medial portion and both ventrobasal / dorsobasal expansions.


Assuntos
Odonatos , Animais , Brasil , Masculino , Tamanho do Órgão
17.
Adv Food Nutr Res ; 101: 129-152, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35940702

RESUMO

The current COVID-19 pandemic has demonstrated that we are not prepared to deal with food security amid unexpected situations; the FAO (Food and Agriculture Organization) has stipulated that the future of our food & agriculture looks challenging toward the year 2050; primarily in response to the fact that global population is expected to increase by 9 billion people by 2050. Although entomophagy has been practiced by humans for thousands of years, until recently, edible insects have gained special attention due to their high nutritional value (particularly their high protein and essential amino acid content) and lower environmental impact that could help alleviate the global food demand. Edible insects are classified into eight main orders belonging to Blattodea (cockroaches and termites), Coleoptera (beetles), Diptera (flies), Hemiptera (cicadas, stink bugs), Hymenoptera (bees, wasps, ants), Lepidoptera (butterflies, moths), Odonata (dragonflies), and Orthoptera (crickets, grasshoppers, locusts). Several traditional cooking (e.g., boiling, roasting, sun-drying) and processing technologies (e.g., pasteurization, enzymatic proteolysis, high pressure processing) have shown that it is feasible to prepare safe and nutritious insects and/or foods with insects. Nevertheless, challenges associated with consumers acceptance to eat insects, as well as potential presence of anti-nutritive factors and allergens, need to be carefully evaluated as the industry grows in the coming years. Foreseeing such food shortages during pandemics and future food security concerns, consumers, scientists, and the food industry need to consider the value of farming insects as promising protein sources.


Assuntos
Borboletas , COVID-19 , Insetos Comestíveis , Odonatos , Alérgenos , Animais , Abelhas , Humanos , Insetos , Pandemias
18.
Behav Processes ; 202: 104741, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36038024

RESUMO

Animals can eavesdrop on other competitors during territorial defense disputes to better choose rivals weaker than themselves and increase the chances of monopolizing resources. In dragonflies, males often compete for access to water bodies, which attract sexually receptive females to mate and lay eggs. During the breeding season, satellite males can observe fights between territory owners and intruders and, therefore, obtain information about potential rivals through visual cues. Consequently, weaker competitors may face more intense competition than stronger ones when defending a territory. In this study, we conducted field experiments with the dragonfly Erythrodiplax fusca to investigate whether eavesdropping on territorial disputes, using visual cues, affects the intensity of competition that territory owners face. We recorded the number of intruders that engage in disputes against males that recently occupied territories in two groups: the "eavesdropping" group (i.e., individuals with access to rivals' prior information) and the control group (i.e., competitors with no access to prior information). The number of intruders was greater in the eavesdropping group compared to the control group. This effect depended on the interaction between the size of the territory owners and the presence of eavesdropping. The number of intruders decreased with increase in the size of the owners in the presence of eavesdropping, but this relationship did not occur in the control group. We discuss the implications of our findings for the male decision-making process to initiate agonistic disputes and how investigating eavesdropping behavior can improve current models of conflict resolution in animals.


Assuntos
Odonatos , Agressão , Animais , Comportamento Animal , Sinais (Psicologia) , Feminino , Masculino , Territorialidade , Água
19.
ACS Appl Mater Interfaces ; 14(36): 40590-40598, 2022 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-36039512

RESUMO

Soft robotics is a rapidly evolving research field that focuses on developing robots with bioinspired actuation/sensing mechanisms and highly flexible soft materials, some of which are similar to those found in living organisms. The hydrogel has the characteristics of excellent biocompatibility, softness, and elasticity, which makes it an ideal candidate material for the preparation of soft robots. Here we utilized a self-healing approach to develop a catalytically driven soft robot, which was constructed by dynamic imine bonds between modular hydrogels. One of the modules was a hydrogel formed by dynamic aldimine cross-linking of chitosan and glutaraldehyde, and the other module was a hydrogel embedded with catalase. The soft hydrogel robot moved because of catalytic reactions between the robot and environment [hydrogen peroxide (H2O2) fuel], giving rise to a fluidic release that supports propulsion, as inspired by the jet-propulsive mechanism in swimming dragonfly larvae. The speed of the soft robot can be mediated by adjusting the concentration of H2O2 and enable/disable movement based on the folding and unfolding of enzymes. In addition, the hydrogel formed by replacing glutaraldehyde with dialdehyde-functionalized PEG2000 had excellent elastic properties, and the soft robot based on PEG2000 had a higher movement speed than that based on glutaraldehyde under the same H2O2 concentration. Moreover, the addition of iron oxide nanoparticles can realize the magnetic guidance of the soft robot and the combination of different modules can realize different motion modes. The highly configurable self-healing catalytic soft robot holds great potential for a variety of interesting applications, including swimming robots, robot-assisted water treatment, and drug release.


Assuntos
Odonatos , Robótica , Animais , Glutaral , Hidrogéis/química , Peróxido de Hidrogênio
20.
Oecologia ; 200(3-4): 307-322, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35969272

RESUMO

Natural enemy ecology strives to unify predator-prey and host-pathogen interactions under a common framework to gain insights into community- and ecosystem-level processes. To address this goal, ecologists need a greater emphasis on: (1) quantifying pathogen-mediated effects on community structure to enable comparisons with predator-mediated effects and (2) determining the interactive effects of combined natural enemies on communities. We conducted a mesocosm experiment to assess the individual and combined effects of predators (dragonfly larvae and adult water bugs) and a pathogen (ranavirus) on the abundance and composition of a larval amphibian assemblage. We found that our three natural enemies structured victim assemblages in unique ways, producing distinct assemblages. Additionally, we found that in combination treatments, predators mainly drove assemblage structure such that the assemblages most closely resembled their respective predator treatments. We also found that predators reduced infection prevalence in combination treatments, and that the magnitude of this effect was dependent on predator identity. Compared to virus-alone treatments, the presence of dragonflies and water bugs reduced infection prevalence by 79% and 63%, respectively. Additionally, the presence of dragonflies eliminated ranavirus infection in two species, which demonstrates the prominent role of predators in disease dynamics in this system. Overall, this work demonstrates the importance of considering natural enemies in community ecology, as each enemy can elicit a unique structural change. Additionally, this study provides a unique empirical test of the healthy herds hypothesis for multi-species assemblages and underscores the importance of advancing our understanding of multi-enemy interactions within communities.


Assuntos
Odonatos , Ranavirus , Animais , Ecossistema , Ecologia , Larva
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