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1.
Quantitative ethnobotany of two east Timorese cultures   总被引:1,自引:0,他引:1  
This is the first time aspects of the ethnobotany of East Timor have been reported. The medicinal plant traditions of two distinct East Timorese cultures, the Laklei and Idate, were studied and compared using quantitative ethnobotanical methods. A total of 86 medicinal plant species were identified. The medicinal plant traditions of the Laklei and Idate cultures were compared using Trotter and Logan’s (1986) quantitative “informant agreement ratio.” On average, informant consensus was greater in Laklei, suggesting a medicinal plant tradition that is more defined than in Idate, where informants are more likely to use the same medicinal plants when treating the same usage categories. Furthermore, only 11 of the 86 medicinal plant species documented were used by both cultures, of which only six had similar mentions. These findings have important implications for the understanding of ethnobotany as they demonstrate how relatively closely situated cultural groups can have significantly different traditional knowledge systems.  相似文献   

2.
The middle Miocene sediments assigned to the Muruyur Beds have yielded abundant faunal remains which indicate an age somewhere near the early part of the middle Miocene, perhaps being earlier in time than Fort Ternan but probably coeval or slightly later than Maboko. Available radioisotopic age determinations suggest that the beds are between 13.5 and 14 m.y. old, which seems to be too young when compared with the biostratigraphic estimate. The importance of Muruyur Beds lies in their rich fossil content which includes hominoids of an age which is in general poorly represented in East Africa’s fossil record. This article places the fossil discoveries on record, and discusses their geological context.  相似文献   

3.
A comparative study of the traditional use of oregano-like herbs in the Mediterranean region provides convincing evidence that the hyssop of the Bible is the carvacrol chemotype of the plantMajorana syriaca. The ancient tradition of ritual use of this plant gave rise to two cultures of condiments: za’atar in the Middle East and oregano in Europe. The flavor of the original hyssop was the determining factor in this development and remained unchanged in oregano and za’atar throughout the centuries.  相似文献   

4.
Human epidermal keratinocytes (HEK) are skin cells of primary importance in maintaining the body’s defensive barrier and are used in vitro to assess the irritation potential and toxicity of chemical compounds. Microfluidic systems hold promise for high throughput irritant and toxicity assays, but HEK growth kinetics have yet to be characterized within microscale culture chambers. This research demonstrates HEK patterning on microscale patches of Type I collagen within microfluidic channels and maintenance of these cells under constant medium perfusion for 72 h. HEK were shown to maintain 93.0%–99.6% viability at 72 h under medium perfusion ranging from 0.025–0.4 μl min−1. HEK maintained this viability while ∼100% confluent—a level not possible in 96 well plates. Microscale HEK cultures offer the ability to precisely examine the morphology, behavior and viability of individual cells which may open the door to new discoveries in toxicological screening methods and wound healing techniques.  相似文献   

5.
A captive adult female capuchin monkey spontaneously manufactured and used tools to groom her vaginal area and four of her own wounds over a six-month period. The wounds apparently occurred during fights with other monkeys living in the same social groups. The monkey often groomed her vaginal area and wounds with tools she had coated with a sugar-based syrup. The monkey did not use tools to groom other body areas, nor did she use tools that were coated with substances other than syrup. This monkey’s unusual habit developed in the context of manufacturing and using tools in a feeding task. These observations demonstrate that the serendipitous performance of particular behaviours in appropriate contexts can lead to the discovery and practice of simple treatment of wounds by a monkey. The independent discovery of simple medicinal procedures in human cultures may have occurred in a similar manner. Such discoveries could have predated the development of sophisticated cultures in which medicinal practices were embedded and eventually recorded.  相似文献   

6.
Dramatic headlines touting new fossil discoveries often proclaim that our view of human evolution has been revolutionized. While this is occasionally the case, it is more often true that new fossils enrich our understanding of our own ancestry or answer scientific questions that could not be resolved with previous data. Even spectacular new discoveries, such as the now famous “hobbit” skeleton (Homo floresiensis), can usually be included in the human family tree without any significant change in the inferences about the phylogenetic relationships or taxonomic status of the rest of its members. It is a testament to the power of evolutionary theory and the careful comparative study of human and other fossils that what we know about human evolution changes so little, even when spectacular new discoveries are announced.  相似文献   

7.
A procedure is outlined for the establishment of a proliferating cell suspension culture of East Indian rosewood (Dalbergia latifolia Roxb.) and efficient plant regeneration from callus derived from such cultures. Callus was induced from hypocotyl segments derived from 1-week-old axenic seedlings on Murashige and Skoog (1962) medium (MS) containing 10.8 μM naphthaleneacetic acid (NAA) and 2.2 μM benzyladenine (BA). Calli were increased by subculturing on MS supplemented with same growth regulators and 10% coconut water (CW). Friable calli were used to initiate cell suspension cultures. Optimum cell proliferation occurred in MS containing 10.8 μM NAA, 2.2 μM BA and 10% CW, using an initial inoculum cell density of 2%. Cell clumps composed of 20–25 cells harvested from suspension cultures at the exponential growth phase readily formed callus within 3 weeks following plating on the semi-solid MS as above. High-frequency shoot-bud differentiation was induced in these calli on MS containing 2.7 μM NAA and 13.3 μM BA. The regeneration frequency declined at higher BA concentrations. The organogenic potential of the cell suspensions was influenced by the age of the culture. Regenerated shoots were rooted on half-strength MS containing 5.7 μM indole-3-acetic acid, 4.9 μM indole-3-butyric acid and 5.3 μM indole-3-propionic acid. The plantlets were acclimatized and established in soil. Received: 22 August 1997 / Revision received: 21 May 1998 / Accepted: 1 June 1998  相似文献   

8.
Over recent years, many discoveries have renewed our knowledge about the oldest stone industries and also about the behaviour and lifestyle of the hominids that made them, not only in East Africa, but also in the Near East, in Trans Caucasia and in southern Europe. If the first tools making hominids appear in East Africa as early as 2.55 million years ago, they are present in the Levant a little over 2 million years ago, as early as 1.81 million years ago at the gates of Europe in Trans-Caucasia, and a little over 1.4 million years ago on the Mediterranean coasts of Europe.  相似文献   

9.
This paper presents a brief review of recent advances in the classification of mammals at higher levels using fossils and molecular clocks. It also discusses latest fossil discoveries from the Cretaceous — Eocene (66–55 m.y.) rocks of India and their relevance to our current understanding of placental mammal origins and diversifications.  相似文献   

10.
We present a model-free approach to the study of the number of false discoveries for large-scale simultaneous family-based association tests (FBATs) in which the set of discoveries is decided by applying a threshold to the test statistics. When the association between a set of markers in a candidate gene and a group of phenotypes is studied by a class of FBATs, we indicate that a joint null hypothesis distribution for these statistics can be obtained by the fundamental statistical method of conditioning on sufficient statistics for the null hypothesis. Based on the joint null distribution of these statistics, we can obtain the distribution of the number of false discoveries for the set of discoveries defined by a threshold; the size of this set is referred to as its tail count. Simulation studies are presented to demonstrate that the conditional, not the unconditional, distribution of the tail count is appropriate for the study of false discoveries. The usefulness of this approach is illustrated by re-examining the association between PTPN1 and a group of blood-pressure-related phenotypes reported by Olivier et al. (Hum Mol Genet 13:1885–1892, 2004); our results refine and reinforce this association.  相似文献   

11.
Production of flavour compounds by yogurt starter cultures   总被引:5,自引:0,他引:5  
The present work studied the production of carbonyl compounds and saturated volatile free fatty acids by pure cultures of Streptococcus thermophilus and Lactobacillus bulgaricus, and by starter cultures for Bulgarian yogurt during cultivation and cooling. The mixed cultures formed volatile aromatic compounds more actively than the pure cultures. A guiding factor in the preparation of the starter cultures was the biochemical activity of Lactobacillus bulgaricus in synthesizing the major carbonyl compounds, acetaldehyde, diacetyl and the volatile fatty acids C2–C10. The activity of the yogurt cultures in synthesizing carbonyl compounds was at its highest during milk coagulation and cooling, up to 7 h. However, maximum concentration was reached by 22–31 h. In the cooled 22–h starter cultures, acetaldehyde predominated (1415.0–1734.2 μg per 100 g) followed by diacetyl (165.0–202.0 μg per 100 g), acetoin (170.0–221.0 μg per 100 g), acetone (66.0–75.5 μg per 100 g), ethanol (58.0 μg per 100 g), and butanone-2 (3.6–3.8 μg per 100 g). The thermophilic streptococcus and lactobacillus cultures, and the starter cultures contained predominantly acetic, butyric and caproic acids. Received 19 June 1997/ Accepted in revised form 10 January 1998  相似文献   

12.
This Editorial has four goals: (1) to inform the readers of ‘Photosynthesis Research‘ about the past of the ‘Historical corner’; which began 20 years ago; (2) to encourage photosynthesis researchers and historians of science to contact me for publishing papers of historical interest; these include: (a) Obituaries and Tributes; (b) historical papers on current and past discoveries and controversies; (c) history of research in specific laboratories, or in specific countries, or at specific conferences; (d) Personal perspectives (not discussed any further); (3) to encourage researchers not to discard, but to save correspondence and data of their discoveries for the future historians by donating them to their Archives, when appropriate (not discussed any further); and (4) to reinforce to the readers that the concept of two-light reaction and two-pigment system was already there in 1959. I mention here three key papers presented at the IXth International Botanical Congress, held at Montreal Canada (in August, 1959) prior to the famous April 9, 1960 paper by Robert Hill and Fay Bendall on the ‘Z-scheme’ of photosynthesis, that was based on thermodynamic and energetic considerations.  This Historical corner Editorial is dedicated to Bessel Kok (1918–1978).  相似文献   

13.
Unopened leaves, petioles and fully opened leaves from micropropagation cultures of five Vitis rotundifolia Michx. varieties were cultured on induction medium to study their embryogenic response. Among the various explants tested, the maximum number of varieties produced embryogenic cultures from unopened leaves followed by fully opened leaves and petioles. Based on morphological differences, two types of embryogenic cultures were identified. Friable cultures typically arose as proembryonic masses (PEM) on induction medium, whereas somatic embryo production without an intervening PEM stage was observed in compact cultures. Of the five varieties tested, the highest frequency of embryogenic response was observed from fully opened leaves of ‘Supreme’ and unopened leaves and petioles of ‘Delicious’. Attempts to initiate suspension cultures from varieties resulted in proliferation and maintenance of ‘Alachua’ and ‘Carlos’ cultures in liquid medium for 16 weeks. Embryogenic potential of varieties was studied on cultures growing on embryo development medium. The maximum number of cotyledonary stage somatic embryos from 0.2 g proembryonic masses were observed in ‘Carlos’ (379.3) followed by ‘Alachua’ (350.0) and ‘Delicious’ (305.0). Cotyledonary stage somatic embryos germinated when cultured on Murashige and Skoog medium containing 1 μM Benzyladenine (BA). Although high embryo germination rates (80–100%) were observed in the varieties tested, plant recovery from germinated somatic embryos ranged from 6–47%. Embryogenic cultures could be maintained on X6 medium and used in genetic engineering studies.  相似文献   

14.
Following the discovery of the West Indies, philosophers of the XVI and XVII centuries came into contact with a particularly unexpected fauna which was considerably different from the documented animals at that time. These animals included the Xenarthra (the sloth, and armadillo) and Marsupialia. These new discoveries occurred during a period of crisis for the traditional Aristotelian and Galenical sciences. This debate developed in two opposing directions: on the one hand towards the confirmation of the well-established tradition of Magia Naturalis, and on the other towards the Galilean Scientia Nova which encouraged people to follow a more mathematical approach when interpreting nature in all its complexity. The first reports and zoological papers of the seventeenth century express the same wonder at these discoveries as all that was “mirum et insolitum” in the typical baroque style of that time.   相似文献   

15.
The effects of aminoethoxyvinylglycine (AVG),1-aminocyclopropane- 1 -carboxylic acid (ACC), dicycyclohexylammonium sulfate (DCHA) and methylglyoxal bis-(guanylhydrazone) (MGBG) on induction of embryogenic competence from the nucellus of two mango genotypes, ‘Tutehau’ (polyembryonic) and ‘Tommy Atkins’ (monoembryonic), were compared. Induction of embryogenic competence in the explanted nucellus of ‘Tommy Atkins’ was more sensitive to AVG and DCHA than ‘Tutehau’. MGBG had no effect on induction of embryogenic competence of either genotype, and ACC suppressed somatic embryogenesis with both cultivars. Ethylene biosynthesis was greater from explanted ‘Tommy Atkins’ cultures. Reducing ethylene biosynthesis with AVG marginally increased the number of embryogenic cultures of ‘Tutehau’, but completely inhibited somatic embryogenesis in ‘Tommy Atkins’ cultures. Ethylene biosynthesis was stimulated by ACC in nonembryogenic cultures of both genotypes and in ‘Tommy Atkins’ embryogenic cultures, in which ethylene biosynthesis was ca 7 X greater than in ‘Tutegau’ embryogenic cultures. The greater sensitivity of ‘Tommy Atkins’ to the ethylene antagonist, AVG, may be due to its greater sensitivity to disturbance of ethylene biosynthesis and spermidine synthesis. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   

16.
The East River (Dong Jiang), a major tributary of the Pearl River (Zhu Jiang, the second largest river in China by discharge), is situated in southern China, which has the highest rates of urbanization and development on Earth. The East River also provides 80% of Hong Kong’s water supply. However, there have been no ecological studies to examine the combined impacts of changes in land use and water quality degradation on this river ecosystem. We tested the hypothesis that land-use disturbance and water quality degradation would significantly reduce benthic biodiversity in the East River by investigating macroinvertebrate community composition and relating it to data on water quality and catchment condition. The percentage of total impervious area within each catchment (%TIA—an indicator of land-use disturbance) was negatively related to a composite water quality index—the ERWQI—we developed for the East River. Modeling by partial least squares projection to latent structures (PLS) showed that family richness and relative abundance index (RAI) of macroinvertebrates were strongly influenced by both %TIA and ERWQI. Multi-response permutation procedure (MRPP) tests showed highly significant differences in family richness composition and RAI of macroinvertebrates among sites in the upper, middle, and lower course of the East River. MRPP also revealed differences in the family richness composition of nighttime drift samples between upper and middle site groups. Abundance (individuals m−3) and total family richness of drifting macroinvertebrates at each site were positively related to %TIA (range: 1.0–8.5%), while drift biomass was negatively related to dissolved oxygen and positively related to total suspended solids. Thus, human disturbances associated with land-use changes (increasing %TIA) and nutrient inputs severely degraded ecosystem integrity and the water quality of the East River and thereby reduced aquatic biodiversity.  相似文献   

17.
18.
The aim of this study was to produce suspension cultures of winter wheat directly from immature embryos bypassing the callus stage, and to determine their capacity for growth and regeneration in comparison to suspension cultures produced from callus. The study was carried out using Polish winter wheat varieties: ‘Grana’ and ‘Rosa’. Immature embryos were isolated, homogenized and transferred directly to liquid medium supplemented with 2,4-D. Actively dividing cell cultures were obtained within 2 months after the cultures were started. Suspension cultures from callus of immature embryos was also produced. With both cultivars, faster growth was observed in the suspension cultures produced directly from embryos than in the suspensions produced from callus. Metabolic activity was higher in the suspension culture produced directly from embryos than in the suspension derived from callus only in ‘Grana’. The production of 1-amiocyclopropane-1-carboxylic acid (ACC), an ethylene precursor, was lower in the suspension cultures produced directly from embryos than in the suspensions produced from callus. Morphogenic capacity was significantly higher in aggregates derived directly from embryos than in aggregates derived from callus. With ‘Rosa’, about one third of the aggregates derived directly from embryos regenerated shoots. Production of ACC was lower in ‘Rosa’ cell culture that regenerated then in other cell cultures that did not. Photosystem II reactions were more efficient in dark green aggregates than in light green or pale green aggregates which were unable to regenerate. With the method presented, wheat cell suspension cultures with a regeneration potential can be produced in 2 or 3 months less time than with traditional methods.  相似文献   

19.
The fossil evidence of the “robust” australopithecines is reviewed with an emphasis on the taxonomic divisions and evolutionary relationships among this group of hominids. The hypodigms of A. robustus, A. crassidens and A. boisei are described, and the significance of morphological variation within and between these species is assessed. Phylogenetic relationships among the “robust” australopithecines are examined using maximum parsimony analysis, and evolutionary scenarios are evaluated in the light of recent discoveries in East Africa.  相似文献   

20.
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