首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 31 毫秒
1.
《Luminescence》2002,17(5):331-342
The journal provides comprehensive literature searches on all aspects of luminescence which will be published in most issues. These lists have been produced regularly since 1986—some by year and some by specialized topic. This survey of papers on Obelia, Renilla, Aequorea and Gonyaulax is drawn from the 2000 literature and covers the biology of these organisms and the applications of genes and proteins from these organisms in analysis.  相似文献   

2.
《Luminescence》2002,17(3):168-189
The journal provides comprehensive literature searches on all aspects of luminescence which will be published in most issues. These lists have been produced regularly since 1986—some by year and some by specialized topic. This survey of papers on Firefly and marine bacterial bioluminescence is drawn from the 2000 literature and covers the biology of these organisms and the applications of genes and proteins from these organisms in analysis.  相似文献   

3.
A survey of the tribe Justicieae from the Caatinga biome, in the State of Bahia, revealed the following four new species of Justicia (Acanthaceae): J. angustissima, J. attenuata, J. chlamidocalyx and J. jacuipensis. J. attenuata and J. jacuipensis are known only from the types; the latter is considered Critically Endangered (CR) because the area where it was collected has been flooded since the construction of the Pedra do Cavalo dam and the region around this area has been extensively disturbed. J. angustissima and J. chlamidocalyx were found in six locations. They have a wide distribution in Central Bahia and the conservation status of both species should be classified as Least Concern (LC). The four species are described and illustrations and comments are provided.  相似文献   

4.
 We investigated whether oviposition by the spittlebug Aphrophora pectoralis on Salix miyabeana and S. sachalinensis in fall 1998 affected shoot growth pattern and further oviposition by subsequent generations of the willow spittlebug in early September 1999 and 2000. Spittlebug oviposition enhanced the growth of current-year shoots on 1-year shoots with oviposition (O-shoots) compared to those without oviposition (N-shoots): the length of current-year shoots increased in 1999 and 2000, the number of current-year shoots increased in 2000 despite a decrease in 1999, and the shoot abscission rate decreased during the 1999 winter. The number of egg masses per current-year shoot was greater on O-shoots than on N-shoots in 1999, and this tendency was reinforced in 2000. The total number of egg masses was greater on O-shoots than on N-shoots in 2000, although there was no significant difference in 1999. There is thus a positive feedback system between spittlebug attack and compensatory growth on willow. Received: April 11, 2002 / Accepted: July 30, 2002 Present address: Center for Ecological Research, Kyoto University, Otsu, Japan Acknowledgments We thank Masanori J. Toda and Andrew Davis for valuable comments and critical reading on this paper. Financial support was provided by a Japanese Ministry of Education, Science, Sports, and Culture Grant-in-Aid for Creative Basic Research to Takayuki Ohgushi. Correspondence to:A. Nozawa  相似文献   

5.
Palmitic acid (Pal) is known to promote apoptosis (Sparagna G et al (2000) Am J Physiol Heart Circ Physiol 279: H2124–H2132) and its amount in blood and mitochondria increases under some pathological conditions. Yet, the mechanism of the proapoptotic action of Pal has not been elucidated. We present evidence for the involvement of the mitochondrial cyclosporin A-insensitive pore induced by Pal/Ca2+ complexes in the apoptotic process. Opening of this pore led to a fall of the mitochondrial membrane potential and the release of the proapoptotic signal cytochrome c. The addition of cytochrome c prevented these effects and recovered membrane potential, which is in contrast to the cyclosporin A-sensitive mitochondrial permeability transition pore. Oleic and linoleic acids prevented the Pal/Ca2+-induced pore opening in the intact mitochondria, this directly and significantly correlating with the effect of these fatty acids on Pal-induced apoptosis in cells (Hardy S et al (2003) J Biol Chem 278: 31861–31870). The specific probe for cardiolipin, 10-N-nonyl acridine orange, inhibited formation of this pore.  相似文献   

6.
A hybrid congenic strain, C57BL/6J.SPRET-Hprt a , carrying 17 map units of Chromosome (Chr) X from Mus spretus on a background of C57BL/6J, has the novel phenotype of low fertility associated with small testis weight. In histological cross-section, many of the tubules in the testes of these congenic mice are empty except for Sertoli cells, while the other tubules appear to be normal. The gene, interspecific hybrid testis weight 1 (Ihtw1) causing this phenotype, has been fine mapped by using the strategy of generating subcongenic strains from recombinants within the congenic region. Genetic and phenotypic analysis of the subcongenic strains has defined a critical region of 1.8 map units for Ihtw1. This region of the genetic map is orthologous to the region on human Chr X containing the gene for the Borjeson-Forssman-Lehman syndrome, an inherited disease in which males show microorchidism. Received: 12 June 2000 / Accepted: 8 September 2000  相似文献   

7.
  1. Diel vertical migration (DVM) is common in aquatic organisms. The trade-off between reduced predation risk in deeper, darker waters during the day and increased foraging opportunities closer to the surface at night is a leading hypothesis for DVM behaviour.
  2. Diel vertical migration behaviour has dominated research and assessment frameworks for Mysis, an omnivorous mid-trophic level macroinvertebrate that exhibits strong DVM between benthic and pelagic habitats and plays key roles in many deep lake ecosystems. However, some historical literature and more recent evidence indicate that mysids also remain on the bottom at night, counter to expectations of DVM.
  3. We surveyed the freshwater Mysis literature using Web of Science (WoS; 1945–2019) to quantify the frequency of studies on demographics, diets, and feeding experiments that considered, assessed, or included Mysis that did not migrate vertically but remained in benthic habitats. We supplemented our WoS survey with literature searches for relevant papers published prior to 1945, journal articles and theses not listed in WoS, and additional references known to the authors but missing from WoS (e.g. only 47% of the papers used to evaluate in situ diets were identified by WoS).
  4. Results from the survey suggest that relatively little attention has been paid to the benthic components of Mysis ecology. Moreover, the literature suggests that reliance on Mysis sampling protocols using pelagic gear at night provides an incomplete picture of Mysis populations and their role in ecosystem structure and function.
  5. We summarise current knowledge of Mysis DVM and provide an expanded framework that more fully considers the role of benthic habitat. Acknowledging benthic habitat as an integral part of Mysis ecology will enable research to better understand the role of Mysis in food web processes.
  相似文献   

8.
In a recent Perspective, Gerth et al. (2011) expressed concern over how Wolbachia (Wolbachia pipientis Hertig) infections may affect the success of DNA barcoding efforts in bees. The potential and realized effects of endosymbiont-induced selective sweeps on host mitochondrial DNA diversity have been noted repeatedly – and rightly so – in the literature for some years. However, we are equally concerned with other misconceptions, including (a) presuming that a positive Wolbachia test indicates a stable infection, (b) presuming that Wolbachia-infected hosts cannot be identified with a single-locus barcode, and (c) inferring specific Wolbachia–mtDNA interactions based only on incomplete genotyping of Wolbachia strains. We address these issues in the context of the Gerth et al. (2011) survey of Wolbachia prevalence among the German bee fauna. We also clarify some of the context-dependent strengths and limitations of DNA barcoding when it is used as a research tool by taxonomists and ecologists.  相似文献   

9.
对2017年11月至2022年1月报道于西藏自治区的15个兰科植物新种、77个兰科植物新记录种统计表明,绝大部分(85.9%)发现于墨脱县。该研究于2021年进一步对墨脱县野生兰科植物资源进行调查,经查阅标本和文献比对鉴定,共发现采自墨脱县的兰科植物西藏新记录属1个——叉柱兰属(Cheirostylis Blume),西藏兰科新记录种10个——巡胡石豆兰(Bulbophyllum sinhoense Aver.)、葡萄天麻(Gastrodia putaoensis X.H.Jin)、中华叉柱兰(C.chinensis Rolfe)、弯瓣大苞兰[Bulbophyllum sasakii(Hayata)J.J.Verm.,Schuit.&de Vogel]、独龙石斛(Dendrobium praecinctum Rchb.f.)、直立山珊瑚[Cyrtosia falconeri(Hook.f.)Aver.]、红唇鸢尾兰(Oberonia rufilabris Lindl.)、白肋菱兰[Rhomboda tokioi(Fukuy.)Ormerod]、带唇兰(Tainia dunnii Rolfe)和绿叶线柱兰(Zeuxine agyokuana Fukuy.),其中巡胡石豆兰和葡萄天麻为2个中国新记录种。结合最新文献及野外植株形态,对以上物种分别进行了描述,提供花期照片和解剖图,并总结了新记录种与相似种之间的差异,以方便鉴别。凭证标本均存放于华东师范大学植物标本馆(HSNU)。  相似文献   

10.
The marine benthic algal flora of Clare Island, off County Mayo, western shore of Ireland, was investigated; collections of intertidal and subtidal marine algae were made at 16 sites along the eastern and southern shores in the years 1990, 1993 and 2000–2002. The data and observations obtained were compared with the results of a similar survey conducted by Arthur Disbrowe Cotton in 1910–1911. Considering the results of the original survey and the new survey together, the marine algal flora of the island currently totals 293 species; 224 species were recorded by Cotton in the original survey, whereas 223 species were identified in the present study. Most species are common to the original and the new list and the main differences are easily explainable; the new survey used SCUBA diving, which allowed the collection of several subtidal species not collected in 1910, and Cotton reported several microscopic green and brown algae, usually difficult to recognise in the field, which were not rediscovered. The most remarkable differences consist in the current presence of some large intertidal brown algae (Bifurcaria bifurcata, Cystoseira foeniculacea and Cystoseira nodicaulis) that were not reported in the survey of 1910. Two algae, Codium fragile subsp. tomentosoides and Asparagopsis armata, were introduced in Europe after the original survey. At present, the benthic algal assemblages of Clare Island still have basically the same structure and distribution as in 1910 and, if compared with other coastal areas of Europe, the intertidal marine environment of Clare Island appears remarkably well conserved.  相似文献   

11.
The third instar larvae of Agabus clypealis (Thomson, 1867) and A. pseudoclypealis Scholz, 1933 are described. Important morphological structures (head, legs, and abdominal segment 8 with urogomphi) are illustrated. Both species share a completely sclerotized abdominal segment 6 with A. setulosus (J. Sahlberg, 1895). Morphological characters and species phenology are discussed in relation to the A. confinis-species group. All available literature records and some new and additional data on distribution of the two species are provided. Agabus clypealis is recorded for the first time from Estonia, and there is no reason to doubt the records of A. pseudoclypealis from Kazakhstan.  相似文献   

12.
A new mouse mutant, punk rocker (allele symbol Kcne1 pkr ), arose spontaneously on a C57BL/10J inbred strain background and is characterized by a distinctive head-tossing, circling, and ataxic phenotype. It is also profoundly and bilaterally deaf. The mutation resides in the Kcne1 gene on Chromosome (Chr) 16 and has been identified as a single base change within the coding region of the third exon. The C to T nucleotide substitution causes an arginine to be altered to a termination codon at amino acid position 67, and predictably this will result in a significantly truncated protein product. The Kcne1 pkr mutant represents the first spontaneous mouse model for the human disorder, Jervell and Lange-Nielsen syndrome, associated with mutations in the homologous KCNE1 gene on human Chr 21. Received: 20 April 2000 / Accepted: 2 June 2000  相似文献   

13.
This study reports (1) a faunistic survey of phytoseiid mites observed inside a vine plot and in neighbouring vegetation (other vine plots and uncultivated areas) and (2) dispersal of phytoseiid mites into the plot studied. These data aim to raise some hypotheses concerning natural colonisation of a vineyard by predatory mites. The study was carried out over 3 years (1999, 2000 and 2001) in an experimental plot planted with two cultivars (Grenache and Syrah) and with Sorbus domestica in a framework of agroforestry investigations. Phytoseiid mites were collected in both cultivated and uncultivated areas surrounding the experimental plot, and their dispersal into the plot studied using “aerial” traps. Densities remained quite low compared to previous studies. The main species encountered in the uncultivated areas and in the traps was Typhlodromus phialatus. Despite the low numbers of phytoseiid mites trapped, densities of phytoseiid mites into the vine field increased during 3 years. Typhlodromus phialatus, the species mainly found in the neighbouring uncultivated areas, was rarely found in vineyards. Another morphologically close species was predominant on vines: Typhlodromus exhilaratus. However, Kampimodromus aberrans the main phytoseiid mite species in vineyards of Southern France was not found in the present survey. Hypotheses for this colonisation process are discussed.  相似文献   

14.
Intergeneric hybrids (ABDJJsS genomes) were made between Triticum aestivum cv. Chinese Spring (CS) and Thinopyrum intermedium. Genomic in situ hybridization (GISH) using genomic DNA probes from Pseudoroegneria libanotica (Hackel) D.R. Dewey (genome S, 2n = 14) was used to study chromosome pairing among J, Js, S and wheat ABD genomes in the hybrids. It was shown that in the hexaploid (ABDJJsS) hybrids, high pairing occurred among wheat chromosomes and among Thinopyrum chromosomes. A closer relationship was observed among the three genomes of Th. intermedium than among the three genomes of T. aestivum. It was further discerned that S genome chromosomes paired with J- and Js-genome chromosomes at a high frequency. The frequency of heterologous pairing between S and J or S and Js chromosomes was higher than those between J and Js chromosomes, indicating that the S-genome was more closely related with these two genomes. Our results provided direct molecular cytogenetic evidence for the hypothesis that S-genome chromosomes are genetically similar to the J-genome chromosomes and, therefore, genetic exchange between these genomes is possible. The discovery of a close relationship among S, J and Js genomes provides valuable markers for molecular cytogenetic analyses using S-genomic DNA probes in monitoring the transfer of useful traits from Thinopyrum species into wheat. Received: 23 August 2000 / Accepted: 5 September 2000  相似文献   

15.
16.
Based on field observations and a survey of the available literature, the functional and evolutionary significance of floral characters ofPelargonium is investigated in relation to a recent infrageneric re-classification. Most of the 208Pelargonium taxa (recognized as species, subspecies or varieties) involved show bee and long-proboscid hovering fly pollination syndromes (about 60% and 25%, respectively), only 7% of the taxa are pollinated by butterflies, some 2 to 4% by hawkmoths and presumably 1% by birds. The heterogeneity ofPelargonium in terms of structural blossom types and pollination syndromes indicates an independent and repeated evolution of convergent flower morphs in the genus and even in sections.  相似文献   

17.
The aim of this work is twofold. First, we survey the techniques developed in Perthame and Zubelli (Inverse Probl 23(3):1037–1052, 2007), Doumic et al. (Inverse Probl 25, 2009) to reconstruct the division (birth) rate from the cell volume distribution data in certain structured population structured population models. Secondly, we implement such techniques on experimental cell volume distributions available in the literature so as to validate the theoretical and numerical results. As a proof of concept, we use the experimental data experimental data reported in the classical work of Kubitschek (Biophys J 9(6):792–809, 1969) concerning Escherichia coli in vitro experiments measured by means of a Coulter transducer-multichannel analyzer system (Coulter Electronics, Inc., Hialeah, FL, USA). Despite the rather old measurement technology, the reconstructed division rates still display potentially useful biological features.  相似文献   

18.
This paper reports on the consequences of large, activity dependent, synaptic conductances for neurons in a large-scale neuronal network model of the input layer 4C of the Macaque primary visual cortex (Area V1). This high conductance state accounts for experimental observations about orientation selectivity, dynamics, and response magnitude (D. McLaughlin et al. (2000) Proc. Natl. Acad. Sci. USA 97: 8087–8092), and the linear dependence of Simple cells on visual stimuli (J. Wielaard et al. (2001) J. Neuroscience 21: 5203–5211). The source of large conductances in the model can be traced to inhibitory corticocortical synapses, and the model's predictions of large conductance changes are consistent with recent intracellular measurements (L. Borg-Graham et al. (1998) Nature 393: 369–373; J. Hirsch et al. (1998) J. Neuroscience 15: 9517–9528; J.S. Anderson et al. (2000) J. Neurophysiol. 84: 909–926). During visual stimulation, these conductances are large enough that their associated time-scales become the shortest in the model cortex, even below that of synaptic interactions. One consequence of this activity driven separation of time-scales is that a neuron responds very quickly to temporal changes in its synaptic drive, with its intracellular membrane potential tracking closely an effective reversal potential composed of the instantaneous synaptic inputs. From the effective potential and large synaptic conductance, the spiking activity of a cell can be expressed in an interesting and simplified manner, with the result suggesting how accurate and smoothly graded responses are achieved in the model network. Further, since neurons in this high-conductance state respond quickly, they are also good candidates as coincidence detectors and burst transmitters.  相似文献   

19.
Calorific and carbon values of marine and freshwater Protozoa   总被引:3,自引:0,他引:3  
Calorific and carbon values were determined for a variety of marine and freshwater Protozoa (Noctiluca miliaris, Euplotes sp.,Eufolliculina sp. respectivelyTetrahymena pyriformis, Paramecium caudatum), their food sources(Bacteria, Dunaliella primolecta, Ceratium hirundinella), and for Protozoa-dominated plankton samples. Most calorific values lie close to the centre of the range covering organisms in general. Low values in some marine samples probably resulted from the retention of bound water in the dried material. When all results were combined with data selected from the literature, the dependence of calorific value on carbon content was highly significant. This relationship is probably also adequately described by an energy-carbon regression through the variety of organic compounds commonly found in organisms. Calorific value expressed per unit carbon is shown to vary little in Protozoa (mean conversion factor 46 J [mg C]–1) or throughout the range of biological materials considered in this study (45 J [mg C]–1).  相似文献   

20.
As part of an ongoing project to substantially increase knowledge of the marine algal flora of the French Pacific territory of New Caledonia, a survey of the Nouméa region was conducted that has resulted in the discovery of 41 previously unrecorded species of macroalgae, including 1 Chlorophyta, 1 Phaeophyceae (Heterokontophyta) and 39 Rhodophyta. Among the biogeographically interesting new records are the green macroalga Rhipilia penicilloides N’Yeurt et Keats (previously endemic to the islands of Fiji some 1000 km east of new Caledonia) and the brown alga Cutleria mollis Allender et Kraft (originally described from Lord Howe Island some 1000 km to the south). The red alga Gloiophloea articulata Weber‐van Bosse, known only from its initial discovery in 1928 from the Mascarene Islands in the western Indian Ocean, is now recorded in the deep‐water channels of the Nouméa region of New Caledonia. The widely distributed Indian Ocean species Corynomorpha prismatica (J. Agardh) J. Agardh has its easternmost distribution record from this area, and Dotyella hawaiiensis (Doty et Wainwright) Womersley et Shepley is recorded for the first time outside its central‐Pacific distribution. These new discoveries represent a 12% increase in the total number of species (377) that are reliably known from New Caledonia.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号