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91.
The mouthparts of Munida sarsi Huus, 1935, including the labrum and paragnaths, are described using LM and SEM, with special attention to the setal composition
and its function. We also used high-resolution macrovideo equipment to record the feeding processes and monitor setae in action.
This combination of morphological and preliminary behavioral data enabled us to arrive at a more comprehensive understanding
of the functional morphology. M. sarsi was found to be an opportunist and capable of handling and eating most kinds of animal tissue. The species can also be a
selective deposit feeder, sorting the sediment by quality and not by size. This sorting is performed by the setae on the medial
rim of the bases of maxilla 1, maxilla 2 and maxilliped 1. Many of the other mouthpart functions ranging from food detection
to ingestion are mapped with comparison to what has been found for other anomurans. Grooming was shown to be a significant
function of many mouthparts, especially the endopod of maxilliped 3. In general the mouthparts closest to the mouth have the
least complex movements and functional scheme, with the mandibles being able to perform only one movement, i.e. cutting or
crunching food objects. Some functions are attributed to the paragnath, the endopod of maxilla 2 and the epipod of maxilliped
1.
Received: 3 October 1999 / Accepted: 22 March 2000 相似文献
92.
Phthalate and PAH concentrations in dust collected from Danish homes and daycare centers 总被引:1,自引:0,他引:1
Sarka Langer Charles J. Weschler Andreas Fischer Gabriel Bekö Jørn Toftum Geo Clausen 《Atmospheric environment (Oxford, England : 1994)》2010,44(19):2294-2301
As part of the Danish Indoor Environment and Children’s Health (IECH) study, dust samples were collected from 500 bedrooms and 151 daycare centers of children (ages 3 to 5) living on the island of Fyn. The present paper reports results from the analyses of these samples for five phthalate esters (diethyl phthalate (DEP), di(n-butyl) phthalate (DnBP), di(isobutyl) phthalate (DiBP), butyl benzyl phthalate (BBzP), di(2-ethylhexyl) phthalate (DEHP)) and three PAHs (pyrene, benz[a]anthracene (B[a]A) and benzo[a]pyrene (B[a]P)). The three PAHs and DEHP were detected in dust samples from all sites, while DEP, DnBP, DiBP and BBzP were detected in more than 75% of the bedrooms and more than 90% of the daycare centers. The dust mass-fractions of both phthalates and PAHs were log-normally distributed. With the exception of DEP, the mass-fractions of phthalates in dust were higher in daycare centers than homes; PAH mass-fractions in dust were similar in the two locations. There was no correlation among the different phthalates in either homes or daycare centers. In contrast, the PAH were correlated with one another – more strongly so in homes (R2 = 0.80–0.90) than in daycare centers (R2 = 0.28–0.45). The dust levels of several phthalates (BBzP, DnBP and DEHP) were substantially lower than those measured in a comparable study conducted 6–7 years earlier in Sweden. Although usage patterns in Denmark differ from those in Sweden, the current results may also reflect a change in the plasticizers that are used in common products including toys. PAH levels were roughly an order of magnitude lower than those measured in Berlin and Cape Cod residences, suggesting that the Danish sites are less impacted by motor vehicle emissions. 相似文献
93.
Dynamic Games in the Economics and Management of Pollution 总被引:1,自引:0,他引:1
Steffen Jørgensen Guiomar Martín-Herrán Georges Zaccour 《Environmental Modeling and Assessment》2010,15(6):433-467
The paper provides a survey of the literature which utilizes dynamic state-space games to formulate and analyze intertemporal,
many decision-maker problems in the economics and management of pollution. 相似文献
94.
Katrine Banke Nørgaard Nina Cedergreen 《Environmental science and pollution research international》2010,17(4):957-967
Background, aim and scope
The ergosterol biosynthesis-inhibiting (EBI) fungicide prochloraz can enhance the effect of other pesticides in a range of animal species. Approximately 50% of the fungicides used in Denmark are EBI fungicides. Hence, if they all have synergising potential, a risk assessment of pesticide mixtures based on additivity might not suffice. This study investigates the synergising potential of six different EBI fungicides representing the imidazoles (prochloraz), the triazoles (epoxiconazole, propiconazole and tebuconazole), the piperidines (fenpropidin) and the morpholines (fenpropimorph) together with the pyrethroid insecticide alpha-cypermethrin. 相似文献95.
96.
Carlos Navarro Florentino de Lope Anders Pape Møller 《Behavioral ecology and sociobiology》2007,61(8):1161-1168
Homeobox genes regulate development of digits, and it has been suggested that the ratio of length of second to length of fourth
digit reflects such genetic effects in a sex-specific manner. We show that digit ratios in the sexually dichromatic house
sparrow Passer domesticus differ between sexes, with males having higher ratios than females, and that individuals produce consistent ratios on the
two feet. If Homeobox or other genes had pleiotropic effects on development of digits, behavior, and physiology of males and
females, we would expect secondary sexual characters and immunity to be related to digit ratio in a sex-specific manner. The
size of the visible part of the black badge in February (a secondary sexual character), but not total badge size, was positively
correlated with digit ratios, suggesting that males with more male-like digit ratios had larger visible badges. Because of
sex-specific effects of development on secondary sexual characters and immunity, we predicted sex-specific differences in
immune response to be related to digit ratio. House sparrows with large digit ratios had weaker T cell-mediated immune response
than individuals with small digit ratios, particularly in females, implying that females with more male-like digit ratios
had weak immune responses. These findings are consistent with the hypothesis that early development, as reflected by digit
ratios, and genetics affect the expression of adult characters that are supposedly strongly contributing to fitness. 相似文献
97.
To determine the source of dissolved inorganic nitrogen (N) in runoff, approx. 35kg N enriched with the stable isotope (15)N (2110 per thousand delta(15)N) was added to a mature coniferous forested catchment for one whole year. The total N input was approx. 50kg ha(-1) year(-1). The enrichment study was part of a long-term whole-catchment ammonium nitrate addition experiment at G?rdsj?n, Sweden. The (15)N concentrations in precipitation, throughfall, runoff and upper forest floor were measured prior to, during, and 3-9years following the (15)N addition. During the year of the (15)N addition the delta(15)N level in runoff largely reflected the level in incoming N, indicating that the leached NO(3)(-) came predominantly from precipitation. Only 1.1% of the incoming N was lost during the year of the tracer addition. The cumulative loss of tracer N over a 10-year period was only 3.9% as DIN and 1.1% as DON. 相似文献
98.
99.
Results of dyeing male yellow-headed blackbirds solid black: implications for the arbitrary identity badge hypothesis 总被引:1,自引:0,他引:1
Summary Territorial male yellow-headed blackbirds that were dyed solid black were similar to controls in their ability to attract mates. They also had no difficulty in defending their territories from floating males. The only remarkable effect of this dramatic color manipulation was that five of the 12 blackened males that regained a territory after being dyed also later took over the better quality territory of another male. Not one of the 11 control males that regained a territory succeeded in such an eviction. This surprising result is interpretable under the theory that conspicuous and distinctive coloration sometimes evolves as an arbitrary recognition badge by making good fighters more memorable to their opponents. With insight gained from these results, we modify and considerably expand the theoretical treatment of this Arbitrary Identity Badge Hypothesis. We also explain why our results for yellow-headed blackbrids should differ so dramatically from those for red-winged blackbirds where blackened males often lost their territories to floating males. 相似文献
100.
Corruption in emergency procurement reduces the resources available for life‐saving operations, lowers the quality of products and services provided, and diverts aid from those who need it most. 1 1 The paper is based on a study for a project of the Chr Michelsen Institute (CMI)'s U4 Anti‐Corruption Resource Centre entitled ‘Corruption in Emergencies’ (see http://www.u4.no ).
It also negatively influences public support for humanitarian relief, both in the affected country and abroad. This paper aims to unpack and analyse the following question in order to mitigate risk: how and where does corruption typically occur, and what can be done? Suggested strategies reflect a multi‐layered approach that stresses internal agency control mechanisms, conflict‐sensitive management, and the need for common systems among operators. 相似文献
It also negatively influences public support for humanitarian relief, both in the affected country and abroad. This paper aims to unpack and analyse the following question in order to mitigate risk: how and where does corruption typically occur, and what can be done? Suggested strategies reflect a multi‐layered approach that stresses internal agency control mechanisms, conflict‐sensitive management, and the need for common systems among operators. 相似文献