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Macropelopiini is a widely distributed tribe of Tanypodinae, with immature stages inhabiting cool seeps, springs, and small streams. The present study evaluated the monophyly and the supporting synapomorphies within a phylogenetic context for the first time for Macropelopiini. The monophyly and the intergeneric relationships were tested by morphological evidence in a cladistic framework, and the information gained from each homoplastic character was evaluated. The monophyly of Macropelopiini is corroborated through the objective synapomorphy ‘outer fringe decreasing from base to apex ending in small spines’ in the pupa, and the subjective synapomorphies ‘tibial spurs with main teeth and short lateral tooth’ in males and ‘dorsal setae arising from prominent tubercles’ in the pupa. Fittkauimyia Karunakaran, 1969 is excluded from Macropelopiini, Gressitius Sublette & Wirth, 1980 is established as a junior synonym of Alotanypus Roback, 1971, and the new combination A lotanypus antarcticus comb. nov. is proposed. Character combination, mainly through the use of the characters with informative taxonomical value, remains an efficient tool to diagnose the Macropelopiini genera. The new genus Paggipelopia gen. nov. for P aggipelopia spaccesii gen. et sp. nov. is erected and the emendation of the species diagnosis of Wuelkerella toncekensis Añón Suárez & Sublette, 2012 is conducted. © 2015 The Linnean Society of London  相似文献   
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Moniliophthora perniciosa and Moniliophthora roreri are phytopathogenic basidiomycete species that infect cacao causing two important diseases in this crop: “Witches’ Broom” and “Frosty Pod Rot”, respectively. The ability of species from this genus (Moniliophthora) to cause disease is exceptional in the family Marasmiaceae. Species in closely related genera including, Marasmius, Crinipellis, and Chaetocalathus, are mainly saprotrophs and are not known to cause disease. In this study, the possibility that this phytopathogenic lifestyle has been acquired by horizontal gene transfer (HGT) was investigated. A stringent genome comparison pipeline was used to identify potential genes that have been obtained by Moniliophthora through HGT. This search led to the identification of three genes: a metallo-dependent hydrolase (MDH), a mannitol phosphate dehydrogenase (MPDH), and a family of necrosis-inducing proteins (NEPs). Phylogenetic analysis of these genes suggests that Moniliophthora acquired NEPs from oomycetes, MDH from actinobacteria and MPDH from firmicutes. Based on the known gene functions and on previous studies of M. perniciosa infection and development, a correlation between gene acquisition and the evolution of the phytopathogenic genus Moniliophthora can be postulated.  相似文献   
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Banana vascular wilt or Moko is a disease caused by Ralstonia solanacearum. This study aimed to sequence, assemble, annotate, and compare the genomes of R. solanacearum Moko ecotypes of different sequevar strains from Brazil. Average nucleotide identity analyses demonstrated a high correlation (> 96%) between the genome sequences of strains CCRMRs277 (sequevar IIA-24), CCRMRs287 (IIB-4), CCRMRs304 (IIA-24), and CCRMRsB7 (IIB-25), which were grouped into phylotypes IIA and IIB. The number of coding sequences present in chromosomes and megaplasmids varied from 3,070 to 3,521 and 1,669 to 1,750, respectively. Pangenome analysis identified 3,378 clusters in the chromosomes, of which 2,604 were shared by all four analyzed genomes and 2,580 were single copies. In megaplasmids, 1,834 clusters were identified, of which 1,005 were shared by all four genomes and 992 were identified as single copies. Strains CCRMRsB7 and CCRMRs287 differed from the others by having unique clusters in both their chromosomes and megaplasmids, and CCRMRsB7 possessed the largest genome among all Moko ecotype strains sequenced to date. Therefore, the genomic information obtained in this study provides a theoretical basis for the identification, characterization, and phylogenetic analysis of R. solanacearum Moko ecotypes.  相似文献   
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1. The absence of creatine was demonstrated enzymically in the hen's-egg yolk and in the albumin contrary to former reports. 2. A comparison of the results obtained by enzymic and colorimetric methods to measure creatine is presented. 3. Creatine phosphate was not detected in the yolk extracts. 4. The content of free arginine enzymically assayed was 15.7mumol in the yolk and 3.38mumol in the albumin. Arginine amounts to practically all of the guanidine compounds in the yolk and one-half of those in the albumin. 5. No glycine amidinotransferase activity was found in the egg-yolk homogenates. 6. The heart of the chick embryo does not receive creatine from the egg and the creatine kinase activity present in this organ starting from the 27th hour of incubation suggests that the enzyme is a constitutive one working probably as an adenosine triphosphatase in a way similar to the kinase isolated from rabbit skeletal muscle. 7. Liver glycine amidinotransferase activity appeared clearly after day 5 of incubation. The specific activity reached a maximum at day 12 and then declined; however, the activity per total mass of liver increased steadily during all the prenatal period. Concomitantly with this steady increase a rise in the creatine content of the whole embryo was observed. An analogous increasing relationship between total liver amidinotransferase activity and liver creatine content was also detected during the postnatal period. 8. Repression of amidinotransferase by creatine cannot be accepted as occurring under physiological conditions since an inverse relationship between the two parameters was not observed. 9. Repression of liver amidinotransferase is observed only when pharmacological concentrations of the exogenous creatine are present in the chick liver.  相似文献   
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The geochronology and taphonomy of internationally important fossil bearing cave deposits were studied, both in the semi-arid Northern Bahia area and the subtropical southeastern Lagoa Santa area of Brazil. Taphonomic analysis suggests that the processes responsible for bone accumulation in the Brazilian caves vary between sites, and taphonomic bias can therefore be significant in causing differences in faunal composition. In the Toca da Boa Vista caves the presence of single articulated skeletons, and the entrance-related distribution indicate that random penetration of animals is the main mechanism of fossil accumulation, a process that biases the assemblage to smaller species, and takes place over extended time periods. In nearby Toca dos Ossos cave transport by runoff in the cave river is predominant, and biases the fauna remains to larger more robust bones and species. Deposition probably also occurred only at times of enhanced runoff giving a more contemporaneous assemblage. Similar processes were responsible for emplacement of the copious fossil remains in the more humid Lagoa Santa area, where terrigenous fossil deposits are found intercalated by massive speleothem calcite layers. In this area runoff under a drier climate probably accounts for the sediment emplacement inside caves. In both areas the mode of emplacement implies bias in the fossil record, resulting in fossil assemblages that do not mirror surface faunas, limiting palaeoenvironmental reconstruction.

Mass spectrometric U-series analysis of speleothem calcite overlaying fossil remains gives minimum ages for fossil deposition. These ages confirm the previous view that many of the deposits derive from the late glacial, but also show that much older material (some > 350,000 yr) is also present. The habitat requirements of critical fossil species such as bats and monkeys strongly suggest that they derive from much wetter periods when forest cover was present in the currently semi-arid Northern Bahia area. Taphonomy exerts a major control on the diversity and mode of emplacement of cave fossil deposits in eastern Brazil and thus detailed sedimentological and hydrological studies coupled with a sound geochronological approach are essential in quantifying the relative importance of each taphonomic processes before faunal and palaeoecological interpretations can be attempted.  相似文献   

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IntroductionChest radiography remains a critical tool for diagnosing intrathoracic tuberculosis (TB) in young children who are unable to expectorate. We describe the radiological findings in children under 3 years of age investigated for TB in the district of Manhiça, southern Mozambique, an area with a high prevalence of TB and HIV.MethodsDigital antero-posterior and lateral projections were performed and reviewed by two independent readers, using a standardized template. Readers included a local pediatrician and a pediatric radiologist blinded to all clinical information. International consensus case definitions for intra-thoracic TB in children were applied.ResultsA total of 766 children were evaluated of whom 43 (5.6%) had TB. The most frequent lesion found in TB cases was air space consolidation (65.1%), followed by suggestive hilar lymphadenopathy (17.1%) and pleural effusion (7.0%). Air space consolidation was significantly more common in TB cases than in non-TB cases (odds ratio 8.9; 95% CI: 1.6-50.5), as were hilar lymphadenopathy (OR 17.2; 95% CI: 5.7-52.1). The only case with miliary infiltrates and 3 with pleural effusions occurred in HIV-infected children.ConclusionFrequent air space consolidation complicates radiological distinction between TB and bacterial pneumonia in young children, underscoring the need for epidemiological contextualization and consideration of all relevant signs and symptoms.  相似文献   
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