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261.
Conflict is an important factor in ongoing climate change debates and its role in management is under increasing scrutiny. In this paper, I present the results of an advanced discourse analysis that analyses trends in the relationship between conflict and climate change. I present two primary discourses dominate discussion: (i) climate as a security risk and (ii) climate as one of many factors affecting power relations that may lead to conflict. Both narratives implicitly or explicitly discuss climate conflict as a cause–outcome relationship, and further primarily construct conflict and climate change within normative frames. Yet, conflict has transformative potential and can be incorporated into management in ways that harness its capacity to drive innovation and lead to more robust and just adaptive governance. I argue for a shift in the discursive frame from a cause– outcome-oriented approach to a process-driven approach, one that treats conflict as an integral part of adaptive governance processes, thus being more just and equitable. Such a shift in focus can lead to positive on ground climate adaptation outcomes, in ways that respect rather than are counter-intuitive to dominant political and societal imbalances and institutional structures.  相似文献   
262.
263.
Annual mean sulphur dioxide concentrations measured at County Hall in central London between 1931 and 1985 showed no clear trend until 1963/64, when a steady decline set in. Results for a number of sites across London for the period 1964/65 to 1984/85 have been divided into three geographic zones: the City of London, a central zone and an outer zone. A steady downward trend is evident in each zone, but is most pronounced in the City of London, especially after 1970. This could reflect the successful introduction of a 1% limit on the sulphur content of oil used within the City, but not elsewhere in London. Annual mean sulphur dioxide concentrations are now around 40 microg m(-3) in all three zones. Highest daily sulphur dioxide levels in both summer and winter have also declined steadily during the period 1964/65 to 1984/85, while at the same time the seasonal pattern of higher winter peaks in daily maxima, which was strong at the beginning of the period, has been virtually eliminated.  相似文献   
264.
ABSTRACT Minicomputer interfaced, continuous, noncontact sensing of the ventilatory behavior of the bluegill (Lepomis macrochirus) was used to investigate the response to exposure to solutions of copper and zinc under various modes of application. The results of these studies indicate that fish respond to sublethal concentrations of these toxicants by increasing the average ventilatory rate as well as decreasing the amplitude of the ventilatory signal. Appropriate statistics for the analysis of these data are also described.  相似文献   
265.
A fetal thigh muscle biopsy was performed at 18 weeks and 6 days' gestation using an automatic 18-gauge biopsy needle. A positive immunoreaction with antisera to the amino- and carboxy-terminals of dystrophin excluded Duchenne muscular dystrophy from this at-risk male.  相似文献   
266.
An ultrasound examination at 17 weeks gestation on a woman with a family history of spina bifida suggested that the fetus had a closed encephalocele. Amniotic fluid alphafetoprotein, rapidly adhering cells and acetylcholinesterase gel electrophoresis were normal. The pregnancy was terminated and the fetus was found to have a large cystic hygroma. It is suggested that in counselling parents of an infant or fetus with a cystic hygroma and with a normal chromosome constitution, ultrasound examination in future pregnancies is advisable, because of the possibility of autosomal recessive inheritance.  相似文献   
267.
D Brown  RS Thompson 《Chemosphere》1982,11(4):427-435
Mussels (Mytilus edulis) were exposed to di-2-ethylhexyl phthalate (DEHP) and to di-isodecyl phthalate (DIDP) over a period of 28 days. The bioconcentration factor (BCF) as measured by 14C analysis, reached estimated plateau levels corresponding to mean BCF values of approximately 2500 and 3500 for the DEHP and DIDP respectively. The mussels were then held in clean seawater for a further 14 days and 14C analysis showed a depuration half-life of approximately 3.5 days for both phthalates. During the whole 42 days of the experiment general observations on the health of the animals showed no evidence of any adverse effects.  相似文献   
268.
Summary The orientation sounds of many bats, almost certainly belonging to the genus Tadarida, were recorded at altitudes of 100 to 300 m above the ground by means of an ultrasonic radio microphone. Both in North Queensland, Australia, and in southern Utah and Nevada, USA, bats were often more numerous at 200 to 300 m than near the ground. Rapid increases in pulse repetition rate often indicated that these bats were actively hunting flying insects. The absence of clutter at high altitudes may significantly facilitate the detection and capture of insect prey.  相似文献   
269.
Specimens of the demosponge Aplysina fistularis forma fulva (Pallas) from the intertidal zone at La Jolla, California, USA, contain two antimicrobial metabolites, aerothionin (1) and homoaerothionin (2). Both metabolites are exuded into seawater. The rates of exudation into artificial seawater were measured under near in situ conditions (7.7x10-4 g aerothionin min-1 g-1 dry weight of sponge) and in an aquarium (8.9x10-3 g min-1 g-1) for undamaged sponges. Sponges responded to a simulated injury by exuding 10 to 100 times as much of these metabolites. The exudation of aerothionin and homoaerothionin may inhibit surface overgrowth by fouling organisms and tissue damage by mobile animals.Please address requests for reprints to Dr. J. E. Thompson  相似文献   
270.
Patella vulgata is one of the most common limpet species on rocky shores throughout the north-eastern Atlantic. Foraging activity of this species has been described during various different diel and tidal phases and several factors have been suggested that might influence the timing of its activity. Among these, inclination of rock surfaces seems to have a clear role, with limpets on horizontal rocks being active during daylight at high water, while limpets on vertical rocks were active during night-time low water. However, by comparing the results of previous investigations it is difficult to separate clearly the effect of any single factor from the effects of their interactions. In the present paper we investigated the simultaneous influence of height on the shore, slope of rock surface and date of sampling (August–September and March–April) on the behaviour of a population of P. vulgata on the Isle of Man (UK). The study was carried out using modern telemetric methods, allowing the activity patterns of limpets to be recorded for long periods of time. The results showed that limpets concentrated their activity during two distinct temporal windows—daytime tide-in and night-time tide-out—while no significant activity was observed during daytime tide-out or night-time tide-in. The observed behaviour appeared to be driven by complex interactions among the three factors examined, and the influence of rock slope alone was not so strong as to override the effect of other factors completely. In addition, a key finding of this study was the conspicuous variability in the individual behaviour of P. vulgata. The greatest level of variability was observed in limpets on vertical surfaces on the upper shore, which showed an extreme switch in behavioural patterns, according to date of sampling (daylight/tide-in foraging during the spring and night-time/tide-out foraging during late summer). In addition, individuals apparently sharing the same set of conditions (inclination, height on the shore and sampling date) differed in their behaviour, and a given behavioural pattern was not always shared by all individuals from a given group. Finally, variability was also observed at the intra-individual level since the same individual could be active during different tidal and diel phases. In conclusion, although the existence of endogenous rhythms has previously been demonstrated in this species, our data clearly show that P. vulgata was able to modulate its behavioural patterns in relation to a variety of exogenous determinants.Communicated by R. Cattaneo-Vietti, Genova  相似文献   
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