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1.
This paper explores the scope and limitations of the economic valuation of biodiversity. How and why is this a useful exercise, but in what way is its usefulness constrained? These issues are discussed with particular reference to cultural values within the context of medicinal plants and phytopharmaceutical development. It is argued that whilst economic valuation is an extremely important and necessary aid to formulating conservation policy, it probably is not that informative about the motivations of people in their use of certain natural resources. This is especially true for the case of medicinal plants where belief systems about the causes of disease and therefore strategies for healing are important. The paper reviews studies which have attempted to put monetary values on medicinal plants and the option values of pharmaceuticals developed from plants, and discusses the applicability of the various approaches. The implications for conservation policy, and for likely collaboration between social and natural scientists is discussed.  相似文献   

2.
Bacillus subtilis or licheniformis facilitated production of soyiru with the best results being given by using both together. Fermentation employing Streptococcus enterococcus was unsuccessful.H.A. Suberu is with the Department of Biological Sciences, Usmanu Danfodiyo University, Sokoto, Nigeria. J.A. Akinyanju is with the Department of Biological Sciences, University of Ilorin, P.M.B. 1515, Ilorin, Nigeria.  相似文献   

3.
4.
Summary Callus derived from the winter annual desert plant Anastatica hiërochuntica was grown on different media, Murashige and Skoog (1962) medium giving the best results. Large amounts of lignified xylem elements were formed resulting in an extremely hard tissue. The growth responses to different auxins, cytokinins and abscisic acid were investigated. When salts (high Na+, Ca2+ and Cl--contents) as they can be found in aqueous extracts of desert soils from a natural A. hiëerochuntica habitat were added to Abou-Mandour (1977) or MS-media, growth of callus was inhibited drastically. In the presence of abscisic acid, however, original growth was completely restored. In salt free control media on the other hand, ABA proved to be inhibitory. Drought stress caused a decrease of both cytokinins and indoleacetic acid in the callus while ABA levels were increased, but by far not as distinct as in intact plants. Proline level was not affected by stress.Abbreviations ABA abscisic acid - AM Abou-Mandour-medium - BAP benzylaminopurine - 2,4-D 2,4-dichlorophenoxyacetic acid - DHZR dihydroxyzeatinriboside - DW dry weight - ELISA enzyme linked immuno sorbent assay - FW freshweight - IAA indole-3-acetic acid - NAA 1-naphthaleneacetic acid - IBA indole-3-butyric acid - IPA isopentenyladenosine - Kin kinetin - MS Murashige and Skoog-medium  相似文献   

5.
A procedure to produce fruits from cultured shoot tips of Cucumis sativus L. cultivar Marketmore-76 in vitro is described. Four-week-old shoot tips, derived from sterile germinated seedlings on a MS medium, were cultured in a 3.8-1 Mason jar using an automated plant culture system. Tips readily generated roots, leaves and flowers after another 4 to 8 weeks in culture. Administration of compressed air at a 300 ml/min flow rate for 30 min 10 or 15 times a day induced the development of parthenocarpic fruits from flowers. Fruits, up to 170 mm long by 35 mm diameter, were obtained within 30 to 45 d after flower opening.Abbreviations APCS automated plant culture system - BA N-(phenylmethyl)-1H-purin-6-amine - BM basal medium - cv cultivar - MS Murashige and Skoog - NAA 1-naphthaleneacetic acid  相似文献   

6.
Jack Kerouac, the author of On The Road, was a central figure of the Beat Generation, a generation which rebelled against middle-class conformity in post–World War II America. Kerouac described himself as “a religious wanderer” (Kerouac 2006: 2), but an examination of his texts and life suggest his travels may also be understood as tourism. Viewed through the prism of tourism, this study will argue, for example, that MacCannell’s notion of the tourist’s quest for reality and authenticity (MacCannell 1989: 3) provides some insight into why Kerouac wrote that just south of Macon, Georgia, he and his travelling companion Neal Cassady stopped and got out of the car, “and suddenly both of us were stoned with joy to realize that in the darkness all around us was fragrant green grass and the smell of fresh manure and warm waters” (Kerouac 1957: 115). As Kerouac rebelled against being, as one of his protagonists in The Dharma Bums put it, “imprisoned in a system of work, produce, consume, work, produce, consume” (Kerouac 2006: 73) he travelled across America on a rapidly improving network of highways, turning “mobility into a retreat” (Holladay and Holton 2009: 42). Kerouac alternately identified himself as a hobo (Kerouac 1973: 181) and “not a real hobo” (Kerouac 1973: 173), but this article asks whether Kerouac’s travels were those of the last in a line of wanderers rebelling against conformity and modernization or a precursor of mobile mass tourism in America.  相似文献   

7.
The effect of nutrients and growth conditions on the accumulation of glutamyl endopeptidase in the culture liquid ofBacillus intermedius 3–19 was studied. Glucose and other readily metabolizable carbon sources were found to suppress the production of the enzyme, whereas inorganic phosphate and ammonium cations enhanced it. Protein substrates, such as casein, gelatin, and hemoglobin, did not affect enzyme production. Some bivalent cations (Ca2+, Mg2+, Co2+) increased the production of glutamyl endopeptidase, but others (Zn2+, Fe2+, Cu2+) acted in the opposite way. The rate of enzyme accumulation in the culture liquid increased as the growth rate of the bacterium decreased, so that the maximum enzyme activity was observed in the stationary growth phase. Based on the results of this investigation, an optimal medium for the maximum production of glutamyl endopeptidase byB. intermedius 3–19 was elaborated.  相似文献   

8.
Ethnographic data combined with the characteristics of the weed species from Bandkeramik settlement sites give hints for the reconstruction of Early Neolithic agricultural practises in Central Europe. In contrast to the Balkan situation with a high diversity in cultivated crops, Bandkeramik field management can be reconstructed as a simple agricultural system with emphasis on summer crop growing. Permanent fields were treated with hoes, digging sticks or similar tools, sown in spring and grazed in autumn and winter. The intensity of field management seems to increase through time as shown by diachrone comparison of archaeobotanical data from Neolithic, Iron Age and Roman times. The absence of winter-cereals such as naked wheat, grown in the Balkan Peninsula, gives a hint of a certain emphasis on stock breeding. Summer crop growing would have had the advantage that the Bandkeramik fields could be grazed after harvest until next spring and would therefore be manured at the same time.  相似文献   

9.
Advanced female age and extended in vitro culture have both been implicated in zona pellucida (ZP) hardening and thickening. This study aimed to determine the influence of (i) the woman's age and (ii) prolonged in vitro culture of embryos on ZP thickness and density using non-invasive polarized light (LC-PolScope) microscopy. ZP thickness and density (measured as retardance) were determined in oocytes, embryos and blastocysts in women undergoing intracytoplasmic sperm injection (ICSI) in two age groups (older, > 38 years; younger, < or = 38 years). A total of 193 oocytes from 29 patients were studied. The younger group contained 100 oocytes and the older group 93 oocytes. The ZP was significantly thicker in metaphase II oocytes in the older group compared with the younger group (mean +/- SD: 24.1 +/- 2.5 microm vs 23.1 +/- 3.3 microm; p = 0.01) but ZP density was equal (2.8 +/- 0.7 nm). By day 2 of culture, embryos from the two groups had similar ZP thickness (22.2 +/- 2.2 microm vs 21.7 +/- 1.6 microm; p = 0.28) and density (2.9 +/- 0.7 nm vs 2.8 +/- 0.8 nm; p = 0.57). For the embryos cultured to blastocyst (older: n = 20; younger: n = 18) ZP thickness was similar in the two groups (19.2 +/- 2.7 microm vs 19.1 +/- 5.0 microm; p = 0.8) but thinner than on day 2. The older group had significantly denser ZP than the younger group (4.2 +/- 0.5 nm vs 3.3 +/- 1.0 nm, p < 0.01). Blastocysts from both groups had significantly denser ZP than their corresponding day 2 embryos (older: 4.2 +/- 0.5 nm vs 2.9 +/- 0.7 nm, p < 0.001; younger: 3.3 +/- 1.0 nm vs 2.8 +/- 0.8 nm, p = 0.013). It is concluded that there is little relationship between ZP thickness and its density as measured by polarized light microscopy. While ZP thickness decreases with extended embryo culturing, the density of the ZP increases. ZP density increases in both age groups with extended culture and, interestingly, more in embryos from older compared with younger women.  相似文献   

10.
It is proposed in this paper that the term somatization as applied to the Chinese requires further exploration. By way of a study of Chinese language usage employing body-related expressions, an indirect method of finding the equivalence in meaning is demonstrated. Results of the study reveal the scope and depth of the symbolic meanings of the body in Chinese culture.  相似文献   

11.
12.
There have not been any studies that review the prevalence of fungal isolates using selective media from samples of banked musculoskeletal tissue retrieved from living and cadaveric donors. A total of 2,036 swab and 2,621 biopsy samples of musculoskeletal tissue from tissue banks were received from the 1st August 2008 till 31st December 2010. Routine culture for fungi using selective media with a prolonged incubation period failed to demonstrate a greater prevalence of fungal isolates than by using non-selective culture media alone. Using selective culture fungi were recovered from only two Sabouraud agar plates (0.1%) but not from non-selective media. During the same period fungi were isolated from three graft samples cultured in non-selective broth media only (0.1%). There was no correlation of fungal isolates from selective or non-selective media inoculated at the same time nor from multiple graft samples collected from the same donor supporting the possibility of an exogenous source for fungal isolates rather than an endogenous source.  相似文献   

13.
Summary Under the control of the repressible PHO5 promoter, the expression of gene encoding interleukin 1 (Il1) was derepressed when the medium was depleted of free inorganic phosphate (Pi). Maximum heterologous protein synthesis was obtained in the presence of 75 mg KH2PO4/1 (for 20 g glucose/l). The successful heterologous protein production greatly depends on nutritional culture conditions as Il1 production efficiency was increased by 83% through optimization of the growth medium. Comparison of different phosphate-limited cultivation strategies led to the development of a batch culture procedure with nutrient pulses to delay induced oxido-fermentative glucose metabolism and increase the Il1 production to 135 mg/l.  相似文献   

14.
The “banana cricket” is one of the preferred laboratory objects used for studying general and applied biological problems. However, the exact identity of this form remains obscure. Correct identification of the insects maintained in culture is vital for the correct prediction of the properties of the object in question and comparative studies. Analysis of acoustic signals showed that the banana cricket from the Moscow Zoo culture did not belong to the Gryllus assimilis (F.) group as it was assumed earlier. Analysis of acoustic signals and genitalia revealed similarity between the banana cricket and insects from the culture maintained at the Institute of Evolutionary Physiology and Biochemistry (IEPhB, St. Petersburg), which were supposed to be Gryllus argentinus (Sauss.). The calling songs and genitalia of crickets from both cultures differed from those of G. argentinus. Thus, the banana cricket and Gryllus sp. from the IEPhB culture belong to the same species but the exact identity of that species has not been yet determined.  相似文献   

15.
Submerged culture of chromium-enriched Termitomyces albuminosus   总被引:2,自引:0,他引:2  
A species of mushroom, Termitomyces albuminosus, was cultured in liquid medium for production of chromium-enriched mycelium. The influence of chromium (Ⅲ) on mycelial growth of T. albuminosus was investigated. An optimum medium composed of 5.6g/L yeast extract, 51.6g/L hydrolyzed rice, 2g/L KH2PO4, and 20mg/L chromium(Ⅲ) with initial pH of 4.5 was obtained by using method of central composite design (CCD). After incubation of 84h, the maximal biomass of chromium-enriched mycelia reached 24.23g DMW(dried mycelial weight)/L with 272μg/g DMW chromium content in 500mL flasks containing 100mL medium with an inoculum of 8% on a shaker of 100r/min under an optimized cultivation condition at 28 ℃.  相似文献   

16.
Amy Ninetto 《Ethnos》2013,78(4):443-464
Through a comparison of privatization programs in two physics institutes, this article explores the ways in which scientists in the Siberian science city of Akademgorodok adapted to the low levels of state funding available to them in the 1990s. Scientists transformed structures that were available under socialism into hybrid state-private ventures. Rather than ‘freeing’ Russian science from its former dependence on the state, however, these changes have reconfigured, and in some cases even strengthened, the relationship between state power and the production of knowledge. Seeing ‘the state’ as it is constituted in Russian scientists' discourse challenges Western models of the autonomy of science.  相似文献   

17.
The effect of peripheral nerve (PN) on neurite outgrowth from retinal explants of adult hamsters was examined.Cultures of retinal explants,and co-cultures of retinal explants and PN were performed using chick retinal basement memebrane (BM) as substrate.The presence of PN increases the number and length of neurite outgrowth.In addition,a high proportion of neurites situated close to PN tend to grow towards it.Since there was no contact between retinal explants and PN,we suggest that PN might secete diffusible substances to attract the neurites to grow towards it.  相似文献   

18.
Robert Paine 《Ethnos》2013,78(1-4):161-172
The Raw and the Cooked. Claude Levi‐Strauss. Jonathan Cape 1970. 387 pp., ill., bibl. Price £3.5.0.

Folktales of Israel. Ed. by Dov Noy with the assistance of Dan Ben Amos. Transi, by Gene Baharav. The University of Chicago Press. Folktales of the World. Chicago 1963. 221 S. $ 4.00.

Politics of Social Research. An inquiry into the ethics and responsibilities of social scientists. Ralph L. Beals. Aldine Publishing Company. Chicago 1969. 228 pp.

African Stone Sculpture. Philip Allison. Percy Lund, Humphries &; Co., Ltd. London 1968. 71 pp. 99 pls. 3 maps. Price 56 s.

The Elementary Structures of Kinship. (Les Structures élémentaires de la Parenté). Claude Lévy‐Strauss. Rev. ed. translated from the French by James Harle Bell, John Richard von Sturmer and Rodney Needham, Editor. Beacon Press, Boston; Eyre &; Spottiswoode Ltd., London. 1969. 541 pp., 87 figs. Price $ 15.00.

Contes sous la Croix du Sud. Giselle de Goustine. (Les littératures populaires de toutes les nations. N.S., T. XIII). Editions G.‐P. Maisonneuve et Larose, Paris 1967. 208 pp.

La divination malgache par le sikidy. Raymond Decary avec la collaboration de Marcelle Urbain‐Faublée. Publications du centre Universitaire des Langues Orientales Vivantes, 6e série, vol. IX. Paul Geuthner, Paris 1970. 111 pp.

Über Lebensraum und Lebensformen des Frühsemiten. Joseph Henninger. Arbeitsgemeinschaft für Forschung des Landes Nordrhein‐Westfalen. Geisteswissenschaften, Heft G 151. Westdeutscher Verlag. Köln und Opladen 1968. 61 Seiten. Kart. DM 6.60.

Indianer von gestern, heute und morgen. Beobachtungen zum Kulturwandel in den Anden Boliviens. Hermann Trimborn. Kulturgeschichtliche Forschungen; 12. Band. Albert Limbach Verlag, Braunschweig 1968. 96 S., 104 Abb., 1 Karte. Preis DM 38:—.

Der Wandel ökonomischer Rollen bei den westlichen Dan in Liberia. Eberhard Fischer. Studien zur Kulturkunde, Band XXI. Franz Steiner Verlag, Wiesbaden. Wiesbaden 1967. 481 S. 4 Taf. 7 Abb. DM 66:—.

An Anthropological Bibliography of South Asia. Together with a Directory of Anthropological Field Research. Vol. III. 1960–64. Compiled by

Elizabeth von Fürer‐Haimendorf and Helen Kanitkar. Le Monde d'Outre‐Mer Passé et Présent, Quatrième Série. Bibliographies VIII. Editions Mounton &; Cie, Paris 1970. 562 pp. Price 193 F.

Man‐apes or Ape‐men? The Story of Discoveries in Africa. Sir Wilfrid E. Le Gros Clark. Holt, Rinehart and Winston, Inc., New York 1967. 150 pp., 33 fig., bibliography, index. Price $3.95.  相似文献   

19.
The fed-batch culture system was employed to enhance production of α-ketoglutarate (α-KG) by the strainsof Corynebacterium glutamicum, whose genes encoding the key enzymes responsible for the biosynthesis of L-glutamate from α-KG were deleted. In a shake flask fermentation, C. glutamicum JH110 in which the 3 genes, gdh (encoding glutamate dehydrogenase), gltB (encoding glutamate synthase), and aceA (encoding isocitrate lyase) were disrupted showed the highest production of α-KG (12.4 g/L) compared to the strains JH102 (gdh mutant), JH103 (gltB mutant), and JH107 (gdh gltB double mutant). In the fed-batch cultures using a 5 L-jar fermenter, the strain JH107 produced more α-KG (19.5 g/L), but less glutamic acid (23.3 g/L) than those produced by the parent strain HH109, as well as JH102. The production of α-KG was significantly enhanced and the accumulation of glutamicacid was minimized by the ammonium-limited fed-batch cultures employing C. glutamicum JH107. Further improvement of α-KG production by the strain JH107 was achieved through the ammonium-limited fed-batch culture with the feeding of molasses, and the levels of α-KG and glutamic acid produced were 51.1 and 0.01 g/L, respectively.  相似文献   

20.
Controlled fermentation of maize was carried out using six strains of Lactobacillus fermentum and one strain of yeast, Saccharomyces cerevisiae, isolated from traditionally fermented maize dough as starter cultures for inoculum enrichement. The fermentations were monitored by pH, acidity, microbiological analysis and taste panel evaluation of two products, kenkey and koko, prepared from the fermented doughs. The strains of L. fermentum used as starter culture dominated the microflora during fermentation and in most inoculated doughs the required pH was attained by 24 h instead of 48 h of dough fermentation. Higher contents of lactic acid bacteria and yeasts were observed in inoculated doughs at the initial stages of fermentation but the spontaneously fermented doughs attained similar lactic acid bacteria and yeasts counts by 24 h of dough fermentation. The organoleptic quality of kenkey and koko prepared from doughs fermented with starter culture for 48 h was not significantly different from the traditional products. Kenkey prepared from doughs fermented for 24 h with starter culture were found to be unacceptable by the taste panel although similarly produced koko was acceptable.The authors are with the Food Research Institute, Council for Scientific and Industrial Research, P.O Box M 20. Accra, Ghana.  相似文献   

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