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AIM: Obstetrical guidelines were established in Japan in 2008, and obstetrical diagnoses and treatments were subsequently standardized nationally. We examined changes in the preterm birth rate (PTBR) and extremely preterm birth rate (EPTBR) following the introduction of such guidelines. METHODS: Information on 50 706 432 live births in Japan between 1979 and 2021, including Japanese reproductive medicine, the childbearing age of pregnant women, and the employment status of reproductive-age women between 2007 and 2020, were obtained from the Japanese government and academic societies. Regression analysis was used to compare chronological changes nationally and those of eight Japanese regions. Regional and national average PTBRs and EPTBRs from 2007 to 2020 were compared by using a repeated measures analysis of variance. RESULTS: From 1979 to 2007, PTBRs and EPTBRs in Japan increased significantly. However, from 2008, the national PTBR and EPTBR decreased until 2020 (p < 0.001) and 2019 (p = 0.02), respectively. From 2007 to 2020, overall PTBR and EPTBR were 5.68% and 0.255%, respectively. A significant difference in the PTBR and EPTBR existed between the eight Japanese regions. During this period, the number of pregnancies using assisted reproductive technology increased from 19 595 to 60 381, pregnant women became older, the employment rate of those of reproductive age increased, and nonregular employment was 54%, which was 2.5 times higher than for men. CONCLUSIONS: In Japan, after obstetrical guidelines were enacted in 2008, PTRBs decreased significantly even under the pressure of increasing preterm births. Countermeasures may be necessary for regions showing high PTBRs.
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Nacimiento Prematuro , Masculino , Embarazo , Recién Nacido , Femenino , Humanos , Nacimiento Prematuro/epidemiología , Resultado del Embarazo , Recién Nacido de Bajo Peso , Embarazo Múltiple , Japón/epidemiología , Tasa de Natalidad , Recien Nacido Extremadamente Prematuro , Vigilancia de la Población , Técnicas Reproductivas AsistidasRESUMEN
The red velvet mite, Balaustium murorum (Hermann), is a pollenophagous free-living mite with a flashy red body. This mite occurs in early spring and lives on sunny surfaces of human-made structures, such as concrete. Hence, it is inevitably exposed to a harsh environment due to solar ultraviolet-B (UV-B) radiation and radiant heat, which cause oxidative stress via the production of reactive oxygen species. The spider mite Panonychus citri that resides on upper leaf surfaces accumulates synthesized keto-carotenoids to protect against oxidative stress. Therefore, we evaluated carotenoid composition in the red pigment of B. murorum. To identify major carotenoids, we performed a high-performance liquid chromatography analysis of intact and de-esterified pigments of B. murorum females. The flashy red pigments of B. murorum consisted of the highly abundant keto-carotenoids astaxanthin and 3-hydroxyechinenone (60 and 38% of major carotenoids, respectively), and a small amount of ß-carotene (2%). Although P. citri is an astaxanthin-rich species, the astaxanthin concentration (per protein) in B. murorum is 127-fold that in P. citri. Due to their high antioxidant activities, those keto-carotenoids probably contribute to the survival of B. murorum in the harsh environment caused by solar UV-B radiation and radiant heat in inorganic habitats.
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Carotenoides , Xantófilas , Femenino , Humanos , Animales , Carotenoides/análisis , Carotenoides/metabolismo , beta CarotenoRESUMEN
The thermal conductivity above room temperature is investigated for LaCoO3-based materials showing spin-state and insulator-metal crossovers. A positive temperature coefficient (PTC) of the thermal conductivity is observed during the insulator-metal crossover around 500 K. Our analysis indicates that the phononic thermal transport is also enhanced in addition to the electronic contribution as the insulator-metal crossover takes place. The enhancement of the phononic component is ascribed to the reduction of the incoherent local lattice distortion coupled with the spin/orbital state of each Co3+ ion, which is induced by the enhanced spin-state fluctuation between low and excited spin-states. Moreover, fine tunability for the PTC of the thermal conductivity is demonstrated via doping hole-type carriers into LaCoO3. The observed enhancement ratio of the thermal conductivity κ T (773 K) / κ T (323 K) = 2.6 in La0.95Sr0.05CoO3 is the largest value among oxide materials which exhibit a PTC of their thermal conductivity above room temperature. The thermal rectification ratio is estimated to reach 61% for a hypothetical thermal diode consisting of La0.95Sr0.05CoO3 and LaGaO3, the latter of which is a typical band insulator. These results indicate that utilizing spin-state and orbital degrees of freedom in strongly correlated materials is a useful strategy for tuning thermal transport properties, especially for designing thermal diodes.
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The activities of social insect colonies are supported by exocrine glands and the tremendous functional diversity of the compounds that they secrete. Many social wasps in the subfamilies Vespinae and Polistinae have two sternal glands-the van der Vecht and Richards' glands-that vary in their features and function across the species in which they are found. Field observations suggest that giant hornets use secretions from the van der Vecht gland to chemically mark targeted nests when workers initiate group attacks on social insect prey. However, descriptions of giant hornets' sternal glands and details about their recruitment behavior are lacking. We describe the morphology of the sternal glands of the giant hornet Vespa soror du Buysson and consider their potential to contribute to a marking pheromone. We also assess the gastral rubbing behavior of workers as they attacked Apis cerana F. (Hymenoptera: Apidae) colonies. V. soror workers have well-developed van der Vecht and Richards' glands on their terminal gastral sternites, with morphologies that robustly support the synthesis, storage, and dissemination of their secretory products. Observations confirm that the van der Vecht gland is exposed during gastral rubbing, but that the Richards' gland and glands associated with the sting apparatus may also contribute to a marking pheromone. Workers briefly but repeatedly rubbed their gasters around hive entrances and on overhead vegetation. Colonies were heavily marked over consecutive attacks. Our findings provide insight into the use of exocrine secretions by giant hornets as they recruit nestmates to prey colonies for group attacks.
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The opisthonotal glands of Astigmata contain monoterpenes, aromatics, aliphatics, and other volatile compounds; some of these compounds act as pheromones and have antifungal effects. This study analyzed volatile compounds secreted by mites on three traditional mite-ripened cheeses from producers (Milbenkäse from Germany, Mimolette and Artisou from France). The mites obtained from various traditional ripened French cheeses (Mimolette, Laguiole, Salers, and Cantal vieux) from stores were also investigated. The gas chromatography (GC) profiles of all their hexane extracts, except the Cantal vieux one, showed almost no differences and were identical to that of Tyrolichus casei Oudemans except for trace components. Based on the GC results, the mites of Cantal vieux were identified as Acarus siro L. For the Artisou and Cantal vieux, not studied before, the influence of the mite secretions on their characteristics was investigated by analyzing the headspace volatiles from the cheeses. According to the results, neral secreted from T. casei is the main compound responsible for the lemon-like flavor of the mite-ripened cheeses, which is, hence, due to a component of the mite secretions rather than the fermentation of the cheese itself. Moreover, the compounds secreted by the mites are not directly added to the cheese through ripening as they were not detected in the odors of the Artisou and Cantal vieux after the mites were removed. However, the consumers of the Artisou usually eat also the cheese rind, and thus, can enjoy its lemon-like flavor fully.
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Queso , Ácaros , Animales , Queso/análisis , Fermentación , Monoterpenos/análisis , Odorantes/análisisRESUMEN
To determine whether the mites used in the ripening process of traditional cheeses are genetically unique to cheese factories, we investigated mites from three types of traditional cheeses, that use mites in the ripening process: 'Würchwitzer Milbenkäse' from Germany and 'Mimolette' and 'Artisou' from France. In addition, traditional ripened cheeses were purchased from cheese specialty stores in France (Mimolette) and Japan ('Laguiole' from France) as well as stores in temporary markets in France ('Salers' and 'Cantal vieux') and the mites obtained from those cheeses were analyzed in this study. Partial sequences of the 28S rRNA gene (28S) were determined and used to reconstruct a phylogenetic tree. Tyrolichus casei, the dominant cheese mite species from the ripening cabinets of three traditional cheese producers and two cheese specialty stores in France and Japan, had identical partial 28S sequences. All specimens from Cantal vieux from a store in the temporary market in France had an identical sequence with Acarus siro and Acarus immobilis in the determined region of the 28S sequences. Mite individuals from Salers from a store in the temporary markets in France shared the same haplotype as Acotyledon paradoxa. For the T. casei individuals from five different localities (19 individuals in total), the nuclear loci were obtained using MIG-seq. More than several thousand genomic regions are amplified simultaneously by multiplex PCR, and targeting regions surrounded by inter-simple sequence repeats (ISSRs) in the genome were sequenced using the MiSeq system (Illumina). SNPs extracted from this genome-wide analysis showed that no genetic structure existed in the populations from any region. Among the five samples from the three regions, which were more than 500 km apart and from completely different environments, the mites had no geographic bias, but all mite individuals were genetically nearly identical. Thus, we found no evidence to support the existence of 'cheese factory-specific' T. casei mites, at least in terms of genetic analysis.
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Acaridae , Queso , Ácaros , Acaridae/genética , Animales , Queso/análisis , Ácaros/genética , Filogenia , ARN Ribosómico 28S/químicaRESUMEN
Two new species of the cockroach genus Eucorydia Hebard, 1929 from the Nansei Islands in Southwest Japan were compared to two closely related congeners, Eucorydia yasumatsui Asahina, 1971 and Eucorydia dasytoides (Walker, 1868). Eucorydia donanensis Yanagisawa, Sakamaki, and Shimano sp. nov. from Yonaguni-jima Island was characterized by an overall length of 12.5-14.5 mm in males. The dorsal side of the male abdomen was entirely dark purple and there was an obscure orange band running down the middle of the tegmen. Eucorydia tokaraensis Yanagisawa, Sakamaki, and Shimano sp. nov. was characterized by an overall length of 12.0-13.0 mm in males and a distinct orange band running down the middle of the tegmen. Eucorydia yasumatsui, E. donanensis, E. tokaraensis and the zonata population of E. dasytoides were divided into four lineages in a maximum-likelihood tree generated from a dataset concatenated from five (two nuclear, 28S rRNA, histone H3, and three mitochondrial, COII, 12S rRNA, 16S rRNA) genes. We recognized the three Japanese lineages E. yasumatsui, E. donanensis, and E. tokaraensis as distinct species, which were also supported by the pairwise genetic distances (5.4-7.8%, K2P) of the COI sequences. Morphometric analysis was performed on the genitalia. A principal component analysis plot revealed that the sizes of the genitalia in the three Japanese species were similar to each other and smaller than that of the zonata population of E. dasytoides. The analysis also revealed that the three Japanese species were distinguished from each other by combinations of the sizes of L3 and L7 sclerites and the shape of R2 sclerite, with some overlapping exceptions.
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Cucarachas/anatomía & histología , Cucarachas/clasificación , Animales , Cucarachas/genética , Femenino , Genitales Masculinos/anatomía & histología , Japón , Masculino , Especificidad de la EspecieRESUMEN
From 2000 to 2019, Japan's reproductive-age population gradually declined by 24%. In comparison, the Chlamydia trachomatis infection rate increased from 2016, with the syphilis infection rate increasing more sharply from 2014. Since 2013, the numbers of foreign tourists to Japan have also increased. From 2011 to 2018, the rate of increase in tourists was 5.02 times, while the rate of increase in syphilis patients was higher at 22.4 times. The lack of a one-to-one relationship between foreign tourists and syphilis cases suggests that cases of syphilis were transmitted to others. Although the prevalence of syphilis in the tourists' home countries (Korea in 2014 and China in 2013) was 20-30 times higher than that in Japan, the Japanese sex industry did not discriminate against foreign tourists, leading to increased STI infections in Japanese female sex workers. Indeed, from 2017 to 2018, a history of working in the sex industry for six months was identified as a risk factor for syphilis. The rise in Chlamydia trachomatis infections has lagged behind that of syphilis by two years, with the rate of increase lower. We suspect the difference in increasing rates of syphilis and chlamydial infections is due to the different methods of infection: syphilis can be transmitted by light physical contact, such as a kiss, whereas chlamydia requires close sexual contact, such as oral sex or sexual intercourse. Regardless, examinations and infection control are necessary to prevent the spread of STIs in Japan due to inbound tourists.
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Infecciones por Chlamydia , Gonorrea , Trabajadores Sexuales , Sífilis , Infecciones por Chlamydia/epidemiología , Chlamydia trachomatis , Femenino , Humanos , Japón/epidemiología , Prevalencia , Factores de Riesgo , Sífilis/epidemiologíaRESUMEN
Riccardoella tokyoensis is a snail parasite recently recorded in Japan. To understand the basic ecology of this mite, we surveyed the life history of a population, including seasonal dynamics, host range, and geographical distribution in East Japan. Seasonal dynamics of the mite were studied in Rinshi-no-mori Park, Tokyo, Japan, from June 2016 to May 2018; thereafter, the morphology of each stage was described. In this park, the host population was infected with the mite in all seasons; however, the prevalence and infection intensities were highest during the warm seasons. Larvae and nymphs were found in the warm seasons. Proto- and tritonymphs were uncommon. To study the host range and geographical distribution, we sampled 1135 terrestrial mollusks from 16 families at 21 locations in Kanto and east Tokai areas from June 2016 to May 2020. Mites were detected at 13 locations, and only clausiliid snails were infected with the mite. Through a laboratory experiment, our observations confirmed that the mite was transmitted to the host lung via the pneumostome. None of the artificially infected snails died, although we maintained the snails for 2 months. No inflammation was found in naturally infected host tissue, suggesting that their virulence against the host snails was low. Riccardoella tokyoensis was not found in the litter layer in the field surveys, and no mite was observed on the external surface of the hosts, suggesting that the major habitat of this mite was the host lung.
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Ácaros , Animales , Especificidad del Huésped , Interacciones Huésped-Parásitos , Japón/epidemiología , Estaciones del Año , CaracolesRESUMEN
The present paper provides information on juvenile stages of seven intertidal oribatid mite species from the East Asian region. Larva and nymphs of the fortuyniid species Fortuynia churaumi, F. shibai, F. rotunda and Alismobates reticulatus are described and details about juvenile morphology of the selenoribatid species, Arotrobates granulatus, Indopacifica taiyo and I. tyida are given. Juveniles of the genus Arotrobates are reported for the first time and strong ventral femoral carinae are supposed to be diagnostic characters. Basically, the conservative morphology of immature stages could be confirmed in every studied taxon and its importance for phylogenetic considerations is emphasized.
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Soil protists are rarely included in ecotoxicological investigations, despite their fundamental role in ecological processes. Moreover, testate amoebae and diatoms contribute considerably to silicon fluxes in soils. We investigated the effects of heavy metals on testate amoebae (species and individual densities) and diatoms (individual densities) in aged soils of a floodplain (Watarase retarding basin, Japan) taking soil samples from two unpolluted reference sites and two polluted sites. The total concentrations of Cu, Pb, and Zn in soil were higher at the polluted sites as compared with the reference sites. The available concentrations of Co, Cu, and Zn in CaCl2 extracts were higher at the polluted sites but available Pb was not detectable. Testate amoeba taxonomic richness was higher in the reference sites (45/38 taxa) than in the polluted sites (36/27 taxa). The reference sites had higher diatom and amoeba densities than the polluted sites. There was a significant negative correlation between total testate amoeba density and heavy metal concentration (available Co), while significant negative correlations were found between diatom density and Co, Cu, and Zn (available and total concentration). Densities of Cyclopyxis kahli cyclostoma, Centropyxis spp., and Trinema complanatum were negatively correlated to concentrations of available heavy metals. The observed decrease in individual numbers due to heavy metal pollution resulted in a considerable decline in protozoic (testate amoebae) and protophytic (pennate diatoms) silicon pools. Our data suggest that heavy metal pollution affects biogeochemical cycling in this system.
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Amoeba/crecimiento & desarrollo , Diatomeas/crecimiento & desarrollo , Metales Pesados/metabolismo , Contaminantes del Suelo/metabolismo , Suelo/química , Amoeba/metabolismo , Cobre/análisis , Cobre/metabolismo , Diatomeas/metabolismo , Biomarcadores Ambientales , Monitoreo del Ambiente , Inundaciones , Japón , Plomo/análisis , Plomo/metabolismo , Metales Pesados/análisis , Suelo/parasitología , Contaminantes del Suelo/análisis , Zinc/análisis , Zinc/metabolismoRESUMEN
This revision of the classification of eukaryotes follows that of Adl et al., 2012 [J. Euk. Microbiol. 59(5)] and retains an emphasis on protists. Changes since have improved the resolution of many nodes in phylogenetic analyses. For some clades even families are being clearly resolved. As we had predicted, environmental sampling in the intervening years has massively increased the genetic information at hand. Consequently, we have discovered novel clades, exciting new genera and uncovered a massive species level diversity beyond the morphological species descriptions. Several clades known from environmental samples only have now found their home. Sampling soils, deeper marine waters and the deep sea will continue to fill us with surprises. The main changes in this revision are the confirmation that eukaryotes form at least two domains, the loss of monophyly in the Excavata, robust support for the Haptista and Cryptista. We provide suggested primer sets for DNA sequences from environmental samples that are effective for each clade. We have provided a guide to trophic functional guilds in an appendix, to facilitate the interpretation of environmental samples, and a standardized taxonomic guide for East Asian users.
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Biodiversidad , Eucariontes/clasificación , Filogenia , Terminología como AsuntoRESUMEN
Sphagnum-dominated ecosystem plays major roles as carbon sinks at the global level. Associated microbial communities, in particular, eukaryotes, play significant roles in nutrient fixation and turnover. In order to understand better the ecological processes driven by these organisms, the first step is to characterise these associated organisms. We characterised the taxonomic diversity, and from this, inferred the functional diversity of microeukaryotes in Sphagnum mosses in tropical, subtropical and temperate climatic zones through an environmental DNA diversity metabarcoding survey of the V9 region of the gene coding for the RNA of the small subunit of the ribosomes (SSU rRNA). As microbial processes are strongly driven by temperatures, we hypothesised that saprotrophy would be highest in warm regions, whereas mixotrophy, an optimal strategy in oligotrophic environments, would peak under colder climates. Phylotype richness was higher in tropical and subtropical climatic zones than in the temperate region, mostly due to a higher diversity of animal parasites (i.e. Apicomplexa). Decomposers, and especially opportunistic yeasts and moulds, were more abundant under warmer climates, while mixotrophic organisms were more abundant under temperate climates. The dominance of decomposers, suggesting a higher heterotrophic activity under warmer climates, is coherent with the generally observed faster nutrient cycling at lower latitudes; this phenomenon is likely enhanced by higher inputs of nutrients most probably brought in the system by Metazoa, such as arthropods.
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Biodiversidad , Eucariontes/aislamiento & purificación , Sphagnopsida/parasitología , Clima , Ecosistema , Eucariontes/clasificación , Eucariontes/genética , Filogenia , TemperaturaRESUMEN
This study demonstrates for the first time the presence of marine-associated mites in the Andaman Sea and Strait of Malacca and reveals a relatively high diversity of these taxa with six species from two different families: Selenoribatidae and Fortuyniidae. Indopacifica, a new genus of Selenoribatidae, is described from Thailand and Malaysia, with two new species, Indopacifica pantai n. sp. and Indopacifica parva n. sp. The genus is characterized by the unique combination of following characters: lacking lamellar ridges, incomplete dorsosejugal suture, fourteen pairs of notogastral setae, and presence of epimeral foveae. A phylogenetic reconstruction based on 18S ribosomal RNA sequences clearly confirms the distinctness of the new genus Indopacifica and places it close to the genus Rhizophobates. The lack of molecular genetic data of possible relatives impedes a clear assessment, and hence, we emphasize the need for further combined approaches using morphological and molecular genetic sequence data. All species show wide distribution areas within this geographic region suggesting that these taxa are good dispersers despite their minute size and wingless body. Molecular genetic data demonstrate recent gene flow between far distant populations of I. pantai n. sp. from the coasts of Thailand and two islands of Malaysia and hence confirm this assumption. The seasonally changing surface currents within this geographic area may favor hydrochorous dispersal and hence genetic exchange. Nevertheless, morphometric data show a slight trend to morphological divergence among the studied populations, whereas this variation is suggested to be a result of genetic drift but also of habitat differences in one population of Alismobates pseudoreticulatus.
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The Ameronothridae are recorded for the first time from Japanese coasts with the new species Ameronothrus yoichi sp. n. from Hokkaido. The report of this species represents the most southern occurrence of an Ameronothrus species in the Asian Pacific region. Ameronothrus yoichi sp. n. can be easily distinguished from its congeners by the conspicuously pusticulate body surface and the loss of dorsal companion setae d on all genua in the adult stage. Based on adult and juvenile morphology, a close relation to Ameronothrus maculatus and A. schneideri is suggested. Ameronothrus yoichi sp. n. is classified as a lichenivorous inhabitant of sediment-free rocky coastal substrates. Due to a lack of genetic sequence data of nearly all ameronothrid species a molecular genetic comparison is yet unfeasible, but a Bayesian inference tree based on the 18S rRNA gene shows a paraphyletic clustering of the ameronothrid A. yoichi sp. n. and Paraquanothrus grahami. http://www.zoobank.org/urn:lsid:zoobank.org:pub:5B772E2C-7D5E-4C86-9955-AB84A84C50DA.
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Species diversity is generally higher in the tropics compared to the temperate zones. The phenomenon that one species of an almost exclusively tropical living genus was able to adapt successfully to the cold northern regions is rather rare. However, the oribatid mite Dolicheremaeus dorni represents such a species and is in the focus of this study. While 180 Dolicheremaeus species are confined to the tropics and subtropics, only five species are known to occur in temperate climates and D. dorni represents the only species with a wider distribution in this climatic region. This species is distributed in Central and Southern Europe and was now recorded for the first time in Austria. A morphological and molecular genetic investigation of specimens from Austria, Poland and Croatia confirmed this distribution pattern and revealed specific geographic clades and haplotypes for each population and hence indicate low gene flow between populations. A further molecular genetic analysis of the 18S rRNA gene sequence of D. dorni confirmed its phylogenetic position within Carabodoidea. Based on record information, this species is associated with trees or tree habitats and seems to be rather a generalist than a specialist for a specific substrate (e.g., tree species) or food source.
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The red mite Balaustium murorum (Hermann) inhabits the Western Palaearctic realm and is well adapted to man-made structures. In Japan, B. murorum had been reported more frequently after the 1980s. A molecular phylogeny based on the nuclear 18S rRNA and mitochondrial COI genes, and including B. murorum individuals from Japan and Austria and representatives of related species from Japan showed four Balaustium species-level lineages in Japan (B. murorum, Balaustium sp. 1, Balaustium sp. 2, Balaustium sp. 3). The B. murorum lineage shared identical 18S sequence and COI haplotype with the Austrian population. Balaustium sp. 1 was detected from the Tokyo and Misaki area (Honshu Island) and was the sister group to B. murorum; the other two lineages inhabited coastal environments of Erimo, Hokkaido Island (Balaustium sp. 2) and Ainan, Shikoku Island (Balaustium sp. 3). The high genetic distances among these four lineages indicate that each lineage is a distinct species, with three of the lineages representing undescribed species. Our results are compatible with the conclusion that B. murorum was introduced to Japan from Europe, although our study did not resolve the polarity or timing of migration events.
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Ácaros/clasificación , Ácaros/genética , Animales , Proteínas de Artrópodos/genética , Austria , Complejo IV de Transporte de Electrones/genética , Haplotipos , Japón , Filogenia , ARN Ribosómico 18S/genéticaRESUMEN
To minimize the degradation of soil organic matter (SOM) content in conventional sugarcane cropping, it is important to understand how the fungal community contributes to SOM dynamics during the decomposition of sugarcane leaf litter. However, our knowledge of fungal diversity in tropical agroecosystems is currently limited. Thus, we determined the fungal community structure on decomposing sugarcane leaf litter and their response to different soil management systems using the internal transcribed spacer region 1 (ITS1) amplicon sequencing method afforded by Ion Torrent Personal Genome Machine (PGM). The results indicate that no-tillage had positive effects on the relative abundance of Zygomycota and of some taxa that may prefer a moist environment over conventional tillage, whereas bagasse mulching decreased the richness of operational taxonomic units (OTUs) and had positive effect on the relative abundance of slow-growing taxa, which may prefer poor nutrient substrates. Furthermore, a combination of no-tillage and bagasse mulching increased the abundance of unique OTUs. We suggest that the alteration of fungal communities through the changes in soil management practices produces an effect on litter decomposition.
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Agricultura/métodos , Biodiversidad , Hongos/fisiología , Hojas de la Planta/microbiología , Microbiología del Suelo , ADN Intergénico/genética , Indonesia , Datos de Secuencia Molecular , Saccharum/microbiología , Análisis de Secuencia de ADNRESUMEN
Oribatid mites are an ancient group that already roamed terrestrial ecosystems in the early and middle Devonian. The superfamily of Ameronothroidea, a supposedly monophyletic lineage, represents the only group of oribatid mites that has successfully invaded the marine coastal environment. By using mitogenome data and nucleic ribosomal RNA genes (18S, 5.8S, 28S), we show that Ameronothroidea are a paraphyletic assemblage and that the land-to-sea transition happened three times independently. Common ancestors of the tropical Fortuyniidae and Selenoribatidae were the first to colonize the coasts and molecular calibration of our phylogeny dates this event to a period in the Triassic and Jurassic era (225-146 mya), whereas present-day distribution indicates that this event might have happened early in this period during the Triassic, when the supercontinent Pangaea still existed. The cold temperate northern hemispheric Ameronothridae colonized the marine littoral later in the late Jurassic-Early Cretaceous and had an ancient distribution on Laurasian coasts. The third and final land-to-sea transition happened in the same geological period, but approx. 30 my later when ancestors of Podacaridae invaded coastal marine environments of the Gondwanan landmasses.
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Metagenómica , Ácaros , Filogenia , Animales , Ácaros/genética , Ácaros/clasificación , Metagenómica/métodos , Genoma Mitocondrial , Mitocondrias/genética , Metagenoma , Evolución Molecular , EcosistemaRESUMEN
The absolute configuration of the iridoid monoterpene chrysomelidial from the oribatid mite, Austrotritia dentate Aoki, was elucidated by the GC-MS and GC comparisons with four synthetic stereoisomers of this well-known natural product. This identification was made possible by asymmetric synthesis of the known alcohol, (5S,8S)-chrysomelidiol. The GC retention time of diol derived from the natural oribatid dial agreed with that of the synthetic (5S,8S)-chrysomelidiol, confirming that the absolute configurations at C5 and C8 positions of the natural chrysomelidial are both S. Chrysomelidial was detected as a single or a major component in nine oribatid mites examined; thus, this compound is considered to be commonly distributed in Oribotririidae where it serves a defensive role.