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A new taxon of chasmosaurine ceratopsid demonstrates unexpected disparity in parietosquamosal frill shape among ceratopsid dinosaurs early in their evolutionary radiation. The new taxon is described based on two apomorphic squamosals collected from approximately time equivalent (approximately 77 million years old) sections of the upper Judith River Formation, Montana, and the lower Dinosaur Park Formation of Dinosaur Provincial Park, Alberta. It is referred to Chasmosaurinae based on the inferred elongate morphology. The typical chasmosaurine squamosal forms an obtuse triangle in dorsal view that tapers towards the posterolateral corner of the frill. In the dorsal view of the new taxon, the lateral margin of the squamosal is hatchet-shaped with the posterior portion modified into a constricted narrow bar that would have supported the lateral margin of a robust parietal. The new taxon represents the oldest chasmosaurine from Canada, and the first pre-Maastrichtian ceratopsid to have been collected on both sides of the Canada–US border, with a minimum north–south range of 380 km. This squamosal morphology would have given the frill of the new taxon a unique dorsal profile that represents evolutionary experimentation in frill signalling near the origin of chasmosaurine ceratopsids and reinforces biogeographic differences between northern and southern faunal provinces in the Campanian of North America.  相似文献   
483.
Some invasion biologists contend their science has reached a consensus on 4 facts: cost estimates of the effects of nonindigenous species provided in papers by Pimentel et al. are credible; invasive species generally, not just predators, pose significant extinction threats; characteristic biological differences distinguish novel from native species, ecosystems, communities, and processes; and ontological dualism, which distinguishes between natural and anthropogenic processes and influences, plays a useful role in biological inquiry. I contend there is no convincing empirical evidence for any of these propositions. Leading invasion biologists cite their agreement about these propositions as evidence for them and impugn the motives of critics who believe consensus should be based on evidence not the other way around.  相似文献   
484.
Purpose. Design for safety (DfS) of workers is amongst the prominent ways of tackling poor occupational safety and health performance in construction. However, in developing countries there is extremely limited research on DfS. This study thus makes an important contribution to the subject of DfS in developing countries by specifically examining the awareness and practice of DfS amongst architects within the construction sector of Nigeria. Materials and methods. A survey of architects, yielding 161 valid responses, was conducted. Results. While there is high awareness of the concept of DfS, the actual practice is low. Additionally, although there is high interest in DfS training, the engagement in DfS training is low. Significantly, awareness of DfS, training and education related to DfS, and membership of a design professional body have very limited bearing on the practice of DfS by architects. Conclusions. The findings are thus symptomatic of the prevalence of influential DfS implementation barriers within the construction sector. Industry stakeholders should seek to raise the profile of DfS practice within the sector. Furthermore, similar empirical studies in the construction sector of other developing countries would be useful in shedding light on the status of DfS in these countries.  相似文献   
485.
Adaptive strategies to deal with uncertainty in water management are often collaboratively developed. So far, however, little attention has been paid to the influence of collaboration on handling uncertainty through adaptive planning. In this paper, we study how collaboration has influenced the handling of uncertainty through adaptive planning for water management strategies for the IJsselmeer area in the Netherlands. We show how a fixation on certainty, different perspectives among actors and unclear responsibilities between arenas affect the handling of uncertainty, and found that it is adversely affected by collaboration. The use of adaptive planning challenged current water uses and system functions, creating resistance from actors. We conclude that developing a shared problem perception, creating a common understanding of uncertainties and ensuring a clear demarcation between the water system, its societal functions and water usage, are necessary to make adaptive planning successful in handling uncertainty.  相似文献   
486.
We report two male fetuses born to a healthy unrelated couple, with agenesis of the corpus callosum identified on detailed 20-week ultrasound scans and confirmed by in-utero MRI. Whole-genome sequencing identified a likely pathogenic missense variant in the CLCN4 gene, establishing this as the causative gene in the family. Pathogenic variants in the CLCN4 gene cause a neurodevelopmental disorder (also called Raynaud-Claes syndrome) inherited in an X-linked pattern. The disorder is characterised by developmental delay, intellectual disability, autism spectrum disorder, epilepsy, mental health conditions, and significant feeding difficulties, predominantly, but not exclusively, affecting males. This is the first report of a prenatal phenotype associated with variants in the CLCN4 gene. The diagnosis of the CLCN4-related neurodevelopmental disorder in this family allowed accurate genetic counseling and discussion of reproductive choices. This leaves uncertainty about the possibility of a postnatal neurodevelopmental phenotype in heterozygous females, which we discuss.  相似文献   
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This paper evaluates the processes and mechanisms available for integrating different types of knowledge for environmental management. Following a review of the challenges associated with knowledge integration, we present a series of questions for identifying, engaging, evaluating and applying different knowledges during project design and delivery. These questions are used as a basis to compare three environmental management projects that aimed to integrate knowledge from different sources in the United Kingdom, Solomon Islands and Australia. Comparative results indicate that integrating different types of knowledge is inherently complex – classification of knowledge is arbitrary and knowledge integration perspectives are qualitatively very different. We argue that there is no single optimum approach for integrating local and scientific knowledge and encourage a shift in science from the development of knowledge integration products to the development of problem-focussed, knowledge integration processes. These processes need to be systematic, reflexive and cyclic so that multiple views and multiple methods are considered in relation to an environmental management problem. The results have implications for the way in which researchers and environmental managers undertake and evaluate knowledge integration projects.  相似文献   
490.
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