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121.
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The prenatal diagnosis of achondrogenesis in association with cystic hygroma is described. Ultrasound findings of severe short-limbed dwarfism, decreased vertebral ossification, and normal ossification of the calvarium were all consistent with achondrogenesis type II. Although the unusual finding of associated cystic hygroma raised the suspicion of a concurrent chromosome abnormality, the karyotype of both fetal lymphocytes and fetal fibroblasts was normal. Autopsy confirmed dilated lymphatic channels in the basal endothelial layer of the skin, cystic hygroma, and coarctation of the aorta. Although previously unreported, we suggest that the features of this case of achondrogenesis indicate an association with lymphatic stasis and jugular lymphatic obstruction sequence in this syndrome.  相似文献   
123.
Abstract

Penicillic acid and ochratoxin A are environmentally important toxic fungal metabolites (mycotoxins) that are synergistic in combination. The effects of penicillic acid on the pancreatic enzyme, :arboxypeptidase A were investigated in vitro and in vivo. A broad range of inhibition in vitro of the enzyme by PA was demonstrated with a half‐maximal inhibitory concentration equal to 1.1 x 10‐4M PA. Inhibition of carboxypeptidase A was time and temperature dependent, and resulted in decreased conversion of parent ochratoxin A to the non‐toxic metabolite, ochratoxin alpha. Studies in vivo demonstrated a penicillic acid‐dependent inhibition of pancreatic carboxypeptidase A activity in the mouse and the chicken following multiple oral exposure. It is postulated that the mode of toxic interaction of the two mycotoxins may be due, in part, to impaired detoxification of ochratoxin A through peni‐cillic acid depletion of carboxypeptidase A activity.  相似文献   
124.
Sexual selection can act through female choice and male–male competition. Although both processes can act simultaneously, they are typically studied independently. Here, we adopt a more integrated approach to studying sexual selection by incorporating measures of both processes using the western rainbowfish Melanotaenia australis, a freshwater fish endemic to northwestern Australia. We assessed male–male competition and female choice separately while measuring the performance of individual males under both processes and used paternity analyses to estimate male reproductive success. We then related the performance of males during each of these stages to their phenotype, which was described using linear measures of size and color pattern traits, and spectrographic measures of the reflectance of color patches. We found that female choice favored relatively large males and that these preferences were consistent within individual females and repeatable between different females. Larger males were also more dominant in the competition trials and sired the majority of offspring produced when females spawned. There was little evidence to suggest that sexual selection acted on male color patterns either via female choice or male contest competition or during subsequent post-mating episodes of sexual selection. We conclude, therefore, that male–male competition and female choice act concordantly to favor relatively large males and that these patterns of mating success are reflected during post-mating episodes of sexual selection.  相似文献   
125.
RaMCo is a prototype version of a decision-support system for coastal-zone management. The model is based on the findings of a multidisiciplinary research program, conducted in Southwest Sulawesi, Indonesia. Different management strategies can be compared on the basis of the short- and long-term consequences. Land-use change has been included in RaMCo in view of the impacts of land-based human activities on the marine environment. The key aspect of the model is a combination of the temporal dynamics of land-use change on the regional (macro-level) scale and spatial dynamics on the local (micro-level) scale. Constrained cellular automata are used to integrate both scale levels. The state changes of the cells depend on the consistency with the macro-scale model, local geographical conditions, and interaction with neighboring cells. In this paper, we discuss the underlying theoretical assumptions of the macro-scale and micro-scale models, some characteristic results for land-use change in the study area, and the validation problem.  相似文献   
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Eye development, optical properties and photomechanical responses were examined in embryos and hatchlings of the southern calamary, Sepioteuthis australis. This species occurs in shallow coastal waters in Australia and New Zealand, and the egg masses were collected in October and December 2004 from Great Oyster Bay, Tasmania. At the earliest developmental stage the eye of the squid was comprised of a hemispherical cup of undifferentiated neural retina, while presumptive iris cell layers and lentigenic precursor cells enclosed a posterior eye chamber. Differentiation of the proximal and distal processes was observed in correspondence with the cornea development and lens crystallization, and occurred before differentiation of the neural retina, which was complete prior to hatching. Longer photoreceptor distal processes were first observed just prior to hatching in the dorsal-posterior retina. After hatching, this difference was much more evident and higher photoreceptor density was found in the central retina. This indicates that the eye of S. australis at this age uses different retina areas for different visual tasks. Optical sensitivity and resolution suggest that juvenile S. australis are diurnal. This study also found functional photomechanical responses of visual screening pigment migration and pupil constriction in S. australis embryos, although complete functionality of the pupil at this stage was uncertain. However, the pupils of squid aged 2 days closed almost completely under bright conditions, showing that photomechanical responses were highly developed in the juvenile squid. These findings indicate that squid embryos are able to perceive visual stimulation, suggesting an early reliance on vision for survival after hatching.  相似文献   
128.
The rollback or proportional model is widely used in pollution control calculations and included in the guidelines for preparing and evaluating state implementation plans. Its basis and limitations are not widely known or understood. In this paper, the basis and limitations of rollback are listed and discussed, and extensions of basic rollback are proposed.  相似文献   
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130.
ABSTRACT

The large share of carbon emitted by energy-intensive industries in the extraction and processing of basic materials must be limited to decarbonise society and the economy. Ways in which the state can govern industrial decarbonisation and contributes to green state theory are explored by addressing a largely ignored issue: the green state’s industrial relations and its role in industrial governance. With insights from a Swedish case study, the tension between the state’s economic imperative and ecological concerns in greening industry are shown to persist. However, as the energy-intensive industry’s previously privileged position in the economy is weakening, industry is opened to decarbonisation strategies. While the case exposes a number of governance challenges, it also suggests potential areas where the state can pursue decarbonisation in energy-intensive industry and points the way to an active role of the green state in governing industrial decarbonisation and greening industry.  相似文献   
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