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A new genus of praying mantis is described, Chlorocalis n. gen., with two species, C. maternaschulzei n. sp. and C. prasina n. sp. from the Greater Mekong Region. Chlorocalis is placed in Mantidae and can be immediately recognized by the presence of dark brown (male) or yellow-whitish (female) oblique stripes on the forewings, a large conical bulge on the clypeus, two large conical bulges on either side of the inferior margin of the lower frons, and the male genitalia with two distal processes on the ventral phallomere. Chlorocalis maternaschulzei is a widespread lowland species with records as west as Nakhon Ratchasima Province, Thailand, and as east as mount Núi Chúa in southern Central Vietnam. We consider this species to be of Least Concern. In contrast, C. prasina is a narrow-range mountain endemic of the Vietnamese Central Highlands in the Annamite range and is assessed by us to be Vulnerable. The new findings demonstrate the still very poor knowledge on praying mantis species diversity in South-East Asia and the urgency to resolve this taxonomic deficiency in the face of biodiversity loss. 相似文献
23.
Shtyrlin Valery G. Borissenok Valery A. Serov Nikita Yu. Simakov Vladimir G. Bragunets Vyacheslav A. Trunin Ivan R. Tereshkina Irina A. Koshkin Sergey A. Bukharov Mikhail S. Gilyazetdinov Edward M. Shestakov Evgeny E. Sirotkina Anna G. Zakharov Alexey V. 《Origins of life and evolution of the biosphere》2019,49(1-2):1-18
Origins of Life and Evolution of Biospheres - Syntheses under shock in nitrogen bubbled samples of the water – formamide – bicarbonate – sodium hydroxide system at... 相似文献
24.
Evgeny B. Lyskov Jukka Juutilainen Veikko Jousmki Juhani Partanen Sviatoslav Medvedev Osmo Hnninen 《Bioelectromagnetics》1993,14(2):87-95
The influence of sinusoidal 45-Hz magnetic fields on the brain functions of 20 volunteers was investigated in a double-blind study using spectral analysis of EEG and measurements of Omega potentials and reaction time (RT). The field strength was 1,000 A/m (1.26 mT) and the duration of exposure was 1 h. Ten volunteers were exposed to a continuous field and ten received an intermittent exposure (1 s on/1 s off). Each person received one real and one sham exposure. One half of the volunteers got the real exposure first and the sham treatment after at least 24 h. For the rest, the sequence was inverse. The measurements of EEG, omega potentials and RT were performed before and after each exposure. Several statistically significant changes were observed, most of them after intermittent exposure. In the EEG, an increase of alpha (7.6–13.9 Hz) activity and a decrease of delta (1.5–3.9 Hz) activity were observed. β waves (14.2–20 Hz) increased in the frontal derivations as did the total power in occipital derivations. The mean and peak frequencies of EEG increased mainly in the frontal derivations. No direct effects on RT were seen. Learning to perform the RT test (decrease of RT in repeated trials), however, seemed to be affected by the exposure. The persons who received real exposure first learned more slowly than those who got sham exposure first. Further experiments are necessary to confirm the findings and for understanding the mechanisms of the effects. © 1993 Wiley-Liss. Inc. 相似文献
25.
Zemskov EA Jana NR Kurosawa M Miyazaki H Sakamoto N Nekooki M Nukina N 《Journal of neurochemistry》2003,87(2):395-406
In order to investigate any effect of truncated mutant huntingtin (tNhtt) aggregation on protein kinase C (PKC) signaling in Huntington's disease (HD), we studied a possible association of PKC isoforms with the aggregates using cellular and transgenic models of HD. In this report we describe an association of mutant tNhtt with at least three PKC isoforms (alpha, delta, zeta), as revealed by co-immunoprecipitation assays and immunocytochemistry in a cellular model of HD (Neuro2a cells expressing tNhtt-150Q-EGFP), as well as a specific association of PKC delta with intranuclear aggregates in a transgenic model (R6/2 mice). Immunoblot analysis of isolated nuclear fractions shows an elevation of nuclear PKC delta in transgenic brain tissue. The observed elevation has a strong similarity with the apoptotic translocation of PKC delta detected in experiments with the mouse neuroblastoma Neuro2a cells. Using a Neuro2a cell line expressing tNhtt with the nuclear localization signal, we demonstrate the association of PKC delta with intranuclear aggregates and present evidence that accumulation of PKC delta in cell nuclei does not depend on mutant htt nuclear translocation. Our results suggest that the association of PKC delta with intranuclear htt-aggregates may affect its apoptotic function in a transgenic model of HD. 相似文献
26.
Hande MP Azizova TV Geard CR Burak LE Mitchell CR Khokhryakov VF Vasilenko EK Brenner DJ 《American journal of human genetics》2003,72(5):1162-1170
Speculation has long surrounded the question of whether past exposure to ionizing radiation leaves a unique permanent signature in the genome. Intrachromosomal rearrangements or deletions are produced much more efficiently by densely ionizing radiation than by chemical mutagens, x-rays, or endogenous aging processes. Until recently, such stable intrachromosomal aberrations have been very hard to detect, but a new chromosome band painting technique has made their detection practical. We report the detection and quantification of stable intrachromosomal aberrations in lymphocytes of healthy former nuclear-weapons workers who were exposed to plutonium many years ago. Even many years after occupational exposure, more than half the blood cells of the healthy plutonium workers contain large (>6 Mb) intrachromosomal rearrangements. The yield of these aberrations was highly correlated with plutonium dose to the bone marrow. The control groups contained very few such intrachromosomal aberrations. Quantification of this large-scale chromosomal damage in human populations exposed many years earlier will lead to new insights into the mechanisms and risks of cytogenetic damage. 相似文献
27.
An acidic O-specific polysaccharide was obtained by mild acid degradation of the Shewanella algae strain BrY lipopolysaccharide and was found to contain L-rhamnose, 2-acetamido-4-[D-3-hydroxybutyramido)]-2,4,6-trideoxy-D-glucose (D-BacNAc4NHbu), and 2-amino-2,6-dideoxy-L-galactose, N-acylated by the 4-carboxyl group of L-malic acid (L-malyl-(4-->2)-alpha-L-FucN) in the ratio 2:1:1. 1H and 13C NMR spectroscopy was applied to the intact polysaccharide, and the following structure of the repeating unit was established:-3)-alpha-D-BacNAc4NHbu-(1-->3)-alpha-L-Rha-(1-->2)-alpha-L-Rha-(1-->2)-L-malyl-(4-->2)-alpha-L-FucN-(1-. The repeating unit includes linkage via the residue of malic acid, reported here for the first time as a component of bacterial polysaccharides. 相似文献
28.
The LPS from Shewanella oneidensis strain MR-1 was analysed by chemical methods and by NMR spectroscopy and mass spectrometry. The LPS contained no polysaccharide O-chain, and its carbohydrate backbone had the following structure: (1S)-GalNAco-(1-->4,6)-alpha-Gal-(1-->6)-alpha-Gal-(1-->3)-alpha-Gal-(1-P-3)-alpha-DDHep-(1-->5)-alpha-8-aminoKdo4R-(2-->6)-beta-GlcN4P-(1-->6)-alpha-GlcN1P, where R is P or EtNPP. There are several novel aspects to this LPS. It contains a novel linking unit between the core polysaccharide and lipid A moieties, namely 8-amino-3,8-dideoxy-D-manno-octulosonic acid (8-aminoKdo) and a residue of 2-acetamido-2-deoxy-D-galactose (N-acetylgalactosamine, GalNAco) in an open-chain form, linked as cyclic acetal to O-4 and O-6 of D-galactopyranose. The structure contains a phosphodiester linkage between the alpha-D-galactopyranose and D-glycero-D-manno-heptose (DDHep) residues. 相似文献
29.
The core-lipid A region of the lipopolysaccharides from Proteus penneri strains 7, 8, 14, 15, and 21 was studied using NMR spectroscopy, ESI MS, and chemical analysis after alkaline deacylation, deamination, and mild-acid hydrolysis of the lipopolysaccharides. The following general structure of the major core oligosaccharides is proposed: [abstract: see text] where all sugars are in the pyranose form and have the D configuration unless otherwise stated, Hep and DDHep=L-glycero- and D-glycero-D-manno-heptose, respectively, K=H, and Q=H in strain 8 or alpha-Glc in strains 7, 14, 15, and 21. In addition, several minor structural variants are present, including those lacking Ara4N in strains 7 and 15 and having the alpha-GlcN residue N-acylated to a various degree with glycine in strains 7, 8, 14, and 21. In strain 14, there are also core oligosaccharides with K=amide of beta-D-GalpA with putrescine, spermidine, or 4-azaheptane-1,7-diamine; remarkably, these structural variants lack either the PEtN group or the alpha-Hep-(1-->2)-alpha-DDHep disaccharide fragment at alpha-D-GalpA. While structural features of the inner core part are shared by Proteus strains studied earlier, the outermost Q-(1-->4)-alpha-GalNAc-(1-->2)-alpha-DDHep-(1-->6)-alpha-GlcN oligosaccharide unit has not been hitherto reported. 相似文献
30.
Vinogradov E 《Carbohydrate research》2002,337(10):961-963
The lipopolysaccharide of Bordetella hinzii was analyzed after various chemical degradations by NMR spectroscopy and MALDI mass spectrometry, and the following structure of the polysaccharide chain was determined: 4-O-Me-alpha-GalpNAc3NAcAN-(1-->[-->4)-beta-GlcpNAc3NAcAN-(1-->4)-beta-GlcpNAc3NAcAN-(1-->4)-alpha-GalpNAc3NAcAN-(1-](n)-where GlcNAc3NAcAN and GalNAc3NAcAN stand for 2,3-diacetamido-2,3-dideoxy-glucuronamide and -galacturonamide, respectively. The polysaccharide chain is terminated with a 4-O-methylated GalNAc3NAcAN residue and is rather short (n < or = 5). 相似文献