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1.
Growth inhibition of plated cells by antimetabolites present in the culture medium was alleviated by corresponding metabolites supplied on filter paper disks placed on the surface of the medium. The metabolites diffused into the medium producing a halo of growing cells (an exhibition zone). Exhibition zones were recorded for 15 pairs of compounds and with cell cultures of Rosa, Acer pseudoplatanus, Daucus carota, Hyoscyamus muticus and Zea mays. The interaction between the compounds could be quantified by measuring exhibition zone diameters and the method was partially optimised for L-ethionine/L-methionine and p-fluorophenylalanine/L-phenylalanine. The exhibition zone method was compared to two other methods, measurement of growth yield and plating efficiency, for demonstrating reversion of growth inhibition.Abbreviations ETH L-ethionine - PFP p-fluorophenylalanine - 5MT 5-methyl-DL-tryptophan - A2C L-azetidine-2-carboxylic acid - PE Plating efficiency - Met L-methionine - Phe L-phenylalanine - Trp L-tryptophan  相似文献   

2.
Successful captive reproduction, management, and exhibition of ermine (Mustela erminea) are unreported. Wild ermine are solitary and asocial specialist predators of small vertebrates. In captivity they alternate brief periods of frenetic activity with long periods of inactivity, are furtive, and because of interindividual aggressiveness, are managed as solitary animals. These species-specific traits have precluded ermine as an ideal animal for captive management and public exhibition. Here we present observations of gestation and litter size, neonatal reproduction, male reproductive variance, and a possible correlation between diet and female reproductive success. We also describe methods of husbandry and of exhibit animal rotation which enhances visitor viewing of the animal.  相似文献   

3.
A number of the chemically modified compounds of salinomycin have been prepared and the structure-activity correlation between complexation affinity for cations, ion transport ability and antimicrobial activity have been investigated.

The results indicate that the terminal carboxylic acid, β-hydroxyketone and allylic alcohol functions in the molecule played an important role in the exhibition of biological activity of the antibiotic.

On the basis of these data, it was concluded that there is a closer parallelism between the antimicrobial and ion-transport activities of salinomycin and its derivatives.  相似文献   

4.
The eradication of the haematophagous isopod ectoparasite Gnathia maxillaris was not achieved after several years of physical elimination of larvae by filtration and chemical treatment with trichlorfon in a captive marine fish population in exhibition aquaria. In this study, different in vitro laboratory assays were performed to find effective alternative anti‐parasitic treatments to trichlorfon (lufenuron, emamectin benzoate, cypermethrin and abamectin). The lethal concentration 50 (LC50) values at 96 hr were calculated for each compound using both larval stages (zuphea and praniza); morphological deformities generated throughout the life cycle, reduction in egg laying and survival of adult forms were also determined. Abamectin, cypermethrin and emamectin benzoate proved effective at limiting further Gnathia maxillaris development, but their efficacy at eradicating an infestation in large tanks was not supported by laboratory assays. However, the use of lufenuron proved to be a good substitute for trichlorfon when treating this type of infestation in large‐volume tanks (LC50 55.8 mg m?3 for praniza). Routine lufenuron treatment once a month via an oral dose at 10 mg kg?1 body weight eradicated G. maxillaris from the exhibition aquaria.  相似文献   

5.
6.
Eremomycin derivatives with benzylated amino groups of both residues of eremosamine and with (R) or (S)-2-amino-4-methylpentyl substituted for N-methyl-D-Leu, the first amino acid residue of its heptapeptide, were synthesized in order to study the role of the peptide bond between the first and second amino acid residues of the heptapeptide moiety of the antibiotic in its interaction with the precursors of the bacterial cell wall peptidoglycan and the exhibition of its antibacterial activity. Comparison of the antibacterial activities of N",N"-dibenzyleremomycin, de-(N-methyl-D-Leu)-N",N"-dibenzyleremomycin, and its N-(2-amino-4-methylpentyl)-derivative (1,2-deoxo-N",N"-dibenzyleremomycin) demonstrated that cleavage or replacement of the first amino acid residue by the corresponding aminoalkyl residue results in a decrease in its antibacterial activity towards both vancomycin-sensitive and vancomycin-resistant strains of microorganisms.  相似文献   

7.
8.
Coumarins with terpene and tert‐butyl substituents were synthesized via Pechmann condensation reaction. New derivatives were investigated in different model system for the exhibition of antioxidant, radical scavenging and membrane‐protective activities. It has been found that 4‐methylcoumarin derivatives with monoterpene moieties exhibit high antioxidant activities. The most active and promising for further investigations is 5‐hydroxy‐6,8‐diisobornyl‐4‐methylcoumarin, containing two isobornyl substituents on the benzopyran ring.  相似文献   

9.
Fusarium wilt in tomato caused by Fusarium oxysporum is the one of the problematic diseases. In this study, 12 native Trichoderma isolates were isolated from different land use types in Rayalaseema region of Andhrapradesh, India and were tested for antagonistic activity against F. oxysporum using dual culture method; the maximum inhibition occurred in WT2 (78.4%) compared to the control. Molecular characterisation using random amplified polymorphic DNA (RAPD) technique reported 91.8% polymorphism among 12 isolates of Trichoderma. Internal transcribed spacer (ITS) region of rDNA amplification with genus-specific ITS1 and ITS4 universal primers produced amplicon size from 569 bp in all the isolates. The study resulted in identification of good competitive Trichoderma isolates against F. oxysporum. A relationship was found between the polymorphism showed by the Trichoderma isolates and their hardness to F. oxysporum during antagonism. Also, exhibition of sufficient genetic polymorphism aids further exploitation in genomic fingerprinting.  相似文献   

10.
The Barbary lion became extinct in the wild around 1942. Since the end of the 19th century, a last purebred captive breeding stock existed at the court of Morocco. The rest of these animals became the core exhibition of the new Rabat Zoo after passing through repeated bottlenecks and possibly some introgression events by foreign lions. This study uses mitochondrial DNA sequencing data to clarify the relationship among these lions and their sub-Saharan and Asian relatives. We analysed mitochondrial cytochrome b sequences obtained from a sample from a Barbary lion descended from a young female of the Barbary lion breeding group at the Rabat Zoo and various other members of the genus Panthera. In our cytochrome-b-based phylogenetic tree, the North African Barbary lion, represented by a biopsy sample from the Neuwied Zoo, joins the Asian lion clade, although it is slightly different from its Asian sister group. However, it is clearly distinct from sub-Saharan lions and can be considered as a genetically defined phylogeographic group of its own. Molecular dating of the extant sub-Saharan and Asian lion groups shows that the split between North African Barbary lions and Asian lions must be considerably more recent than 74–203 kilo years ago.  相似文献   

11.
Hero, Hawk, and Open Hand rated as a must-see for anyone with an interest in art of the ancient Americas or ancient art in general—an exhibition whose breadth and depth in terms of visual material would be difficult, if not impossible, to replicate. This review takes a look beyond the immediate frame of the exhibition at some additional context related to the appreciation of these objects as ancient art, including some reflection on the original objectives of the exhibition and what appeared, at least to this anthropologist, as palpably missing or unspoken.  相似文献   

12.
Plastination provides a new method, governed by medical technique rather than religious ritual, by which human remains may be transformed from unstable/wet to stable/dry. In the Körperwelten/Body Worlds exhibition, the public pay to view plastinated bodies, and are invited to donate their bodies for plastination after death. This article addresses the question of whether Body Worlds visitors accept plastination for display as a legitimate form of disposal. Three sources of data are drawn on: the ethnographer's account of his first visit to the exhibition in Brussels; the written comments of visitors to the London exhibition; and the stated motives of some donors. Plastination as final disposal is accepted by the vast majority of visitors; they perceive the dry, odourless body interiors within the clinical, scientific framework encouraged by the exhibition, and are often fascinated by what they see. This is complicated, however, by certain surface features and modes of display which enable the problematic reinsertion of personhood. So, plastination itself is accepted, but not all forms of display.  相似文献   

13.
The purposes of this study were to determine 1) the life history characteristics of a captive colony of the arboreal folivore Pseudocheirus peregrinus maintained on a browse free diet under enhanced laboratory conditions, 2) the direction and magnitude of life history differences from wild population values, and 3) the feasibility of developing captive colonies of this and related species for conservation and research programs. Rates of reproduction, growth, and development; demographic trends; behavioral patterns pertinent to exhibition; and management and medical techniques are reported. Fecundity was 67% greater than that of wild populations and there was an approximate four-fold increase in the rate of offspring survival to sexual maturity. These trends were due largely to reduced post-pouch emergence mortality and the decay of reproductive seasonality. The results indicate that a properly designed “artificial” diet can support significantly enhanced reproduction in a trophic specialist. Other demographic, developmental, and behavioral measures found to be consistent with those reported from wild populations indicate that there was no significant life history distortion caused by the management regime. Empirical data are presented showing that the common ringtail is nocturnal, has low rates of activity, and has specific space and substrate preferences. These results suggest ways in which the animals' physical environment can be manipulated to improve exhibition. We conclude that the reproductive rates of other ringtail possum species might also be enhanced under comparable management conditions.  相似文献   

14.
ABSTRACT

Museums around the globe have experienced important changes in recent years in response to decolonisation processes and the demands of indigenous peoples. French museums are no exception, but the transformations have certain French hallmarks. This article explores the way France is dealing with its colonial legacy and, by means of two case studies, unravels the diverse political and historical particularities of the French context. The first looks at the results of a comparative analysis of the French and Québécois public’s response to the travelling exhibition E tū ake: Standing Strong produced by the Museum of New Zealand Te Papa Tongarewa. The second focuses on the repatriation ceremony of Māori toi moko (tattooed preserved heads) that took place in Paris in January 2012. These two case studies examine the French uses of concepts such as ‘community’, ‘minority’, and ‘indigeneity’ as well as the complex relations between religion and rationality, ancestral presence and materialism in French public life. The article investigates how these concepts participate in the fabric of French society, and thus in shaping contemporary museum landscapes.  相似文献   

15.
C. D. Schaaf 《Zoo biology》1984,3(4):373-377
Behaviorists can undertake noninvasive studies of zoo animals using only the simplest of research tools, unlike those biologists who are concerned with functions below the level of the whole, living organism. With careful interpretation, the results of behavioral studies can be applied to improve the management, husbandry, and exhibition of wild mammals in captivity. This often involves comparisons with research results obtained from studies of animals in the wild, since the behavior of captive specimens may in some measure be altered. Examples are given involving the breeding biology or social organization of three species: (1) barasingha or swamp deer (Cervus duvauceli), (2) mongoose lemur (Lemur mongoz), and (3) drill (Papio leucophaeus). Suggestions are made to improve the allocation of time and resources for research by zoo personnel, including a greater reliance on cooperative efforts to solve problems of common interest.  相似文献   

16.
This paper present the content of the Musée de l'Homme exhibition “Us and them: from prejudice to racism” and provides a detailed explanation of how this content has been presented to the public. In a second section of this paper we explain some of the analysis and concepts, from a biological anthropology perspective, that were the foundation of the exhibition and provides some information about the current situation in France.  相似文献   

17.
We conducted a survey of 63 public aquariums in Japan by means of a questionnaire asking if a green seaweed, Caulerpa taxifolia, was cultured or exhibited in aquariums under the network of the public aquarium association of Japan in 1997. Of 51 aquariums, 16 cultured or exhibited C. taxifolia. Most of the public aquariums possessing C. taxifolia purchased them from aquarium shops or received them from another public aquarium as a donation. Notojima aquarium reported temporal establishment of C. taxifolia in the Sea of Japan between the summer and autumn of 1992 and 1993. C. taxifolia was released into the sea from a 1 m3 cage that was submerged in an open pool. Two colonies with diameters less than 2 m were found near the mouth of a water outflow pipe in both years. Molecular analysis of the ITS rDNA gene of the aquarium strain of Notojima clarified that the seaweed is the same as the aquarium-Mediterranean and Californian invasive strain. Unsuccessful establishment of the invasive strain of C. taxifolia in the Sea of Japan is probably due to water temperatures in winter that are lethal for C. taxifolia. C. taxifolia remains present in many public and private aquariums. If C. taxifoliawere to be released in more temperate waters of Japan, there would be a high risk of establishment and, thus, impact on the marine ecosystem. This suggests that the trade, culture and exhibition of C. taxifolia should be strongly avoided to reduce the chances of accidental release of this harmful species.  相似文献   

18.
The electrochemical reduction of the heme protein sterol-14α-demethylase from Mycobacterium tuberculosis (CYP51b1, or further CYP51) was investigated. Direct electron transfer was demonstrated between CYP51 and graphite screen-printed electrodes modified with gold nanoparticles and with the membrane-like synthetic surfactant didodecyl dimethylammonium bromide. The formal potential of the Fe3+/Fe2+ pair, E 1/2, is equal to −273 mV (vs. Ag/AgCl). The cathodic current corresponding to the reduction of oxygen by immobilized heme protein was registered in the presence of oxygen. Addition of lanosterol, one of the substrates of the CYP51 family, to the oxygenated solution caused a concentration-dependent increase in the reduction current in voltammetric and amperometric experiments. Ketoconazole, an inhibitor of CYP51, inhibited the catalytic cathodic current in the presence of lanosterol. Electrochemical reduction of CYP51 may serve as an adequate alternative to the reconstituted system, which requires additional redox partners for the exhibition of catalytic activity of heme proteins of the cytochrome P450 superfamily. Published in Russian in Biokhimiya, 2007, Vol. 72, No. 6, pp. 805–811.  相似文献   

19.
Anita Herle 《Ethnos》2013,78(2):253-274
Preparations for a centenary exhibition to mark the 1898 Cambridge Anthropological Expedition to the Torres Strait incorporated cross-cultural collaborative work, reflecting the changing roles of museums as sites for contact and research combining curatorial expertise and indigenous knowledge. Specific objects in the collections of the University of Cambridge Museum of Archaeology and Anthropology continue to be active intermediaries in the relationship between museum staff and Torres Strait Islanders and the museum itself has become an important field site. This paper provides an ethnography of the process of creating the exhibition and explores different ways that many of the objects displayed have resonance for Islanders today.  相似文献   

20.
With synchronously grown cells of an aerobic unicellular marine cyanobacterium Synechococcus sp. Miami BG 043511, changes in the activities of anoxygenic, nitrogenase-dependent hydrogen photoproduction and oxygen photoevolution were measured under non-growing hydrogen production conditions. Interestingly, synchronously grown cells, incubated in light under an argon atmosphere, exhibited cyclic changes in the activity of nitrogenase-catalyzed hydrogen production for approximately 20- to 25-h intervals. Cyclic photosynthetic oxygen production activity also appeared in approximately the same intervals. However, changes in hydrogen production and oxygen production activities were inversely correlated and temporally separated. Stepwise accumulation of hydrogen in closed vessels was also observed in approximately 24-h cycles in these non-growing cells. These observations in non-growing cells suggest that this unicellular aerobic, nitrogen-fixing cyanobacterium may have an endogenous system to control the exhibition of cyclic rhythms, in addition to the previously studied cell cycle-oriented system. Expression and switching between these two systems may be related to the sufficiency or insufficiency of nitrogen growth nutrients. The possibility of the existence of a common control factor of the two systems involving glycogen is also discussed.  相似文献   

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