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1.
MALCOLM CRICK 《The Australian journal of anthropology》1985,15(3):231-242
This article turns an anthropological sensitivity onto a literary text from its own society. It takes Joan Lindsay's novel ‘Picnic at Hanging Rock’ and ‘reads’ it in the light of ideas prominent in recent anthropological writings (the ideas of Lévi-Strauss are particularly used): it also articulates an interpretation by using notions current in modern literary and cultural analysis. The article points out that Lindsay's text has most commonly been interpreted as being about mysterious natural forces injurious to man. Whilst the text explores the disjunction between nature and culture, the article interprets the text as exploring the nature of cultural institutions and cultural processes. 相似文献
2.
Southern Alameda County was the only area in California to take part in the 1954 nationwide field trials for testing poliomyelitis vaccine. Besides the contribution made in evaluating the vaccine, other benefits were:1. Participation contributed to the control of a serious communicable disease.2. Inoculations of vaccine during the field trials in all probability prevented some cases of paralytic poliomyelitis among children in southern Alameda County.3. The community became better informed about poliomyelitis and more interested in the local health department.4. Local physicians had an opportunity to contribute to important research and to give a valuable community service.5. The staff of the Alameda County Health Department became better informed and better prepared for any future responsibilities in poliomyelitis immunization programs.Other conclusions reached as a result of participation in the 1954 field trials are that the initial planning of the study was hasty and not sufficiently representative of medical and administrative thinking. If the trials had been planned for 1955 instead of 1954 there would have been sufficient time for research to be completed, professional information to be assured and for sound design of study. 相似文献
3.
JOY GRAYSON MALCOLM EDMUNDS 《Biological journal of the Linnean Society. Linnean Society of London》1989,37(3):263-279
Caterpillars of the poplar and eyed hawkmoths (Laothoe populi and Smerinthus ocellata respectively) were reared under different conditions in order to determine why final instar caterpillars vary in colour. Poplar hawkmoth caterpillars normally rest on the undersides of leaves. Dull green and redspotted caterpillars are genetically determined polymorphisms. Caterpillars that are not dull green, however, can become white when fed on Populus alba or yellow-green when fed on Salix fragilis. Experiments showed that it is the reflective qualities of the leaves that determines which colour the caterpillar develops: if the young larva sees white then it becomes white, but if it sees green, grey or black then it becomes yellow-green. Young eyed hawkmoth larvae always developed into grey-green final instar caterpillars under our rather poorly-illuminated rearing conditions, but when reared on wild plants in white muslin sleeves they became whitish-green. In this species also it appears that colour of the final instar is determined by the reflectance of the substrate perceived by the young caterpillar. 相似文献
4.
The distribution of Naididae (Oligochaeta) in the littoral zone of selected lakes in North Wales and Shropshire 总被引:1,自引:0,他引:1
MALCOLM J. McELHONE 《Freshwater Biology》1982,12(5):421-425
SUMMARY. The distribution of twenty species of Naididae found in seventeen lakes in North Wales and Shropshire is described. Fewer species were observed in the mountain lakes in Snowdonia in comparison to the more productive lakes of Anglesey and Shropshire.
Substrate was an important factor influencing the distribution of naids within lakes, A small number of sexually mature individuals was found in more productive lakes in the summer and autumn months. Sexually mature individuals of Stylaria lacustris were cultured in the laboratory; the population doubled its numbers, by asexual reproduction, in 12 days at 15°C. In Llyn Coron a natural population of S. lacustris doubled its numbers in 40 days. The gut contents of S. lacustris consisted of periphyton. 相似文献
Substrate was an important factor influencing the distribution of naids within lakes, A small number of sexually mature individuals was found in more productive lakes in the summer and autumn months. Sexually mature individuals of Stylaria lacustris were cultured in the laboratory; the population doubled its numbers, by asexual reproduction, in 12 days at 15°C. In Llyn Coron a natural population of S. lacustris doubled its numbers in 40 days. The gut contents of S. lacustris consisted of periphyton. 相似文献
5.
JONES R.; BUCHANAN IRENE C.; WILKINS M.B.; FEWSON C.A.; MALCOLM A.D.B. 《Journal of experimental botany》1981,32(2):427-441
The total activity (capacity) of phosphoenolpyruvate carboxylasein crude extracts of leaves of Bryophyllum fedtschenkoi, measuredon a fresh weight basis, varies considerably with leaf positionand with photoperiodic treatment. No diurnal variation in capacitywas detected under long day or short day conditions.The enzyme in freshly prepared crude extracts is about 50 timesmore sensitive to inhibition by malate at pH 7 than that inaged extracts, or in the fully purified state. Desensitizationin extracts proceeds rapidly unless protective measures aretaken, and appears to be irreversible. A pH-dependence studyshows that the effect of desensitization on the kinetic parametersof malate inhibition is identical to that of increasing thepH by 2.0 units over a wide range, but the maximum velocityat pH 7.8 is virtually unaffected. The significance of the resultsfor both the experimental determination of cyclic changes inenzyme capacity, and the theories concerning the mechanism ofa circadian rhythm of phosphoenolpyruvate carboxylase activityin vivo are discussed. 相似文献
6.
SYNOPSIS. The eyespot of the zoospore of Tetracystis excentrica (a green alga) has been studied by light and electron microscopy. In Tetracystis the eyespot consists of about 110 osmiophilic granules which form a plate in the anterior third of the cell. The granules are about 80 Å in diameter and are found in the outermost portion of the chloroplast; they commonly show hexagonal close packing and a hexagonal shape. The granules are confined positionally by the chloroplast envelope and an inner thylakoid. The plasmalemma over the eyespot is thickened and is separated from the chloroplast envelope by a 50 mμ space. The eyespot of Tetracystis is compared with others reported in the literature and the possible functional significance of these studies is discussed. The possibility that the eyespot plate in Tetracystis serves as a shading device rather than the primary photoreceptor is considered. 相似文献
7.
8.
Development in the Floating World: Defenses of Eggs and Embryos Against Damage from UV Radiation 总被引:2,自引:0,他引:2
EPEL DAVID; HEMELA KATHERINE; SHICK MALCOLM; PATTON CHRIS 《Integrative and comparative biology》1999,39(2):271-278
Eggs and embryos of many aquatic organisms develop in the watercolumn and can experience ultraviolet radiation with potentiallydeleterious effects. This is especially vexing for floatingembryos that develop in the surface or neuston layer. Radiationdamage can be a particular problem for these embryos since thecell division cycle during the cleavage period is quite shortand often these cycles do not have mitotic checkpoints to insurefaithful transmission of DNA to the daughter cells. This couldresult in cell division with unrepaired DNA in the blastomeres,which could impact embryogenesis and the transmission of thegenome through the germ line. Described strategies to restrictradiation damage include mechanisms to limit oxidative damageand the use of sunscreens such as the mycosporines to curb radiationto sensitive targets. We describe a particularly ingenious useof sunscreens in the tunicate embryo, the use of extra-embryoniccells to shield the embryo from potentially harmful UV-A andUV-B radiation. We also raise questions regarding the natureof UV damage to embryos (is it DNA or also protein) and thecharacteristics of DNA repair in such embryos. It is likelythat unique mechanisms are present in floating embryos thatdevelop in this air-water interface to assure that cell andgenomic integrity are maintained in this challenging environment. 相似文献
9.
10.
Alternative explanations for rising dissolved organic carbon export from organic soils 总被引:8,自引:0,他引:8
CHRISTOPHER D. EVANS PIPPA J. CHAPMAN† JOANNA M. CLARK† DON T. MONTEITH‡ MALCOLM S. CRESSER§ 《Global Change Biology》2006,12(11):2044-2053
Since 1988, there has been, on average, a 91% increase in dissolved organic carbon (DOC) concentrations of UK lakes and streams in the Acid Waters Monitoring Network (AWMN). Similar DOC increases have been observed in surface waters across much of Europe and North America. Much of the debate about the causes of rising DOC has, as in other studies relating to the carbon cycle, focused on factors related to climate change. Data from our peat‐core experiments support an influence of climate on DOC, notably an increase in production with temperature under aerobic, and to a lesser extent anaerobic, conditions. However, we argue that climatic factors may not be the dominant drivers of DOC change. DOC solubility is suppressed by high soil water acidity and ionic strength, both of which have decreased as a result of declining sulphur deposition since the 1980s, augmented during the 1990s in the United Kingdom by a cyclical decline in sea‐salt deposition. Our observational and experimental data demonstrate a clear, inverse and quantitatively important link between DOC and sulphate concentrations in soil solution. Statistical analysis of 11 AWMN lakes suggests that rising temperature, declining sulphur deposition and changing sea‐salt loading can account for the majority of the observed DOC trend. This combination of evidence points to the changing chemical composition of atmospheric deposition, particularly the substantial reduction in anthropogenic sulphur emissions during the last 20 years, as a key cause of rising DOC. The implications of rising DOC export for the carbon cycle will be very different if linked primarily to decreasing acid deposition, rather than to changes in climate, suggesting that these systems may be recovering rather than destabilising. 相似文献