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Elisabetta M. Falchetti 《Evolution》2012,5(1):104-122
Biological museums can promote interest in evolution and contribute to its understanding. Modern exhibitions generally emphasize the main concepts of evolutionary theory: biodiversity and adaptation. In 2009 at the Zoological Museum of Rome, to celebrate Charles Darwin, a pilot didactic project was carried out for schools and the general public in order to involve people in evolutionary issues, to stimulate interest and at constructing knowledge about evolution. An exhibition consisting of exhibits and laboratory settings was created. The thematic contexts of the exhibition and the practical experiences were aimed at facing some epistemological obstacles that influence the understanding of evolution and at constructing some “framing concepts” that, on the contrary, could facilitate it. The communicative and didactic strategies were all participative and interactive, based on the personal questioning and restructuring of preexisting knowledge. Behaviors, conversations, and comments by the participants were monitored in order to record any possible change of ideas, interests, attitudes, and learning. 相似文献
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文章研究的是一个具有时滞的媒介传播流行病模型.假定长期的发病率是双线性大规模行动的方式,确定了疾病是否流行的阈值R_0.当R_0≤1时,得到无病平衡点是全局稳定的,即疾病消失;当R_0〉1时,得到地方病平衡点.在具有时滞的微分模型中,时滞与载体转变成传染源的孵化期有关。我们研究了时滞对平衡点稳定性的影响,研究表明,在从寄生源到载体的传播过程中,时滞可以破坏动力系统并且得到了Hopt分支的周期解. 相似文献
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Robert M. Bloomfield 《Evolution》2012,5(1):38-42
In 2009, the Natural History Museum, London celebrated the bicentenary of Charles Darwin and the sesquicentennial of his seminal work The Origin of Species by Means of Natural Section by commissioning a new contemporary artwork as a permanent insertion into the famous grade one listed Waterhouse architecture in South Kensington. This article explores the motivation and delivery of this extraordinary work and its deeper message for today and tomorrow. 相似文献
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Specimens of fish in the Naturhistoriska riksmuseet, Stockholm, which are type specimens of species described by Linnaeus are listed. A total of 94 taxa is represented in the collection. The sources for the typification of each taxon are given and the existence of type material in other collections is noted. A short history of this collection of fishes is given as it relates to confirmation of the original nature of the specimens.
Most of the taxa represented came from the collection of King Adolf Fredrik (1710–1771) and were described by Linnaeus in the Museum Adolphi Friderici Volumes 1 and 2 (1754a, 1764) or from Fredrick Hasselqvist's (1722–1752) collections in North Africa and the Mediterranean borderlands. 相似文献
Most of the taxa represented came from the collection of King Adolf Fredrik (1710–1771) and were described by Linnaeus in the Museum Adolphi Friderici Volumes 1 and 2 (1754a, 1764) or from Fredrick Hasselqvist's (1722–1752) collections in North Africa and the Mediterranean borderlands. 相似文献
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During a two-year period a senior case-worker was seconded by a voluntary family case-work agency, the Liverpool Personal Service Society, to work with three general practitioners. The commonest reasons for referral of the 157 new patients to the social worker over this study period were extreme poverty; housing, matrimonial, and psychiatric problems; and problems of fatherless families. The successful and valuable co-operation between the general practitioners, case-worker, and various specialist professional and financial services of the Society have proved that a professional social worker has an important role in the general-practice team. 相似文献
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Monique Scott 《Evolution》2010,3(3):403-409
As natural history museums are increasingly challenged to represent the complexities of human evolution, new innovations are required to create dynamic, dialogic experiences between museum scientists and museum audiences. After the opening of the Spitzer Hall of Human Origins in 2006, I had the opportunity to take my academic experience in physical anthropology to public education in the Sackler Educational Laboratory for Comparative Genomics and Human Origins. In the lab, I was able to intervene in museum visitors’ preconceptions of human evolution in a novel, informal educational setting. 相似文献
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Finding out whether Plasmodium spp. are coevolving with their vertebrate hosts is of both theoretical and applied interest and can influence our understanding of the effects and dynamics of malaria infection. In this study, we tested for local adaptation as a signature of coevolution between malaria blood parasites, Plasmodium spp. and its host, the great tit, Parus major. We conducted a reciprocal transplant experiment of birds in the field, where we exposed birds from two populations to Plasmodium parasites. This experimental set-up also provided a unique opportunity to study the natural history of malaria infection in the wild and to assess the effects of primary malaria infection on juvenile birds. We present three main findings: i) there was no support for local adaptation; ii) there was a male-biased infection rate; iii) infection occurred towards the end of the summer and differed between sites. There were also site-specific effects of malaria infection on the hosts. Taken together, we present one of the few experimental studies of parasite-host local adaptation in a natural malaria system, and our results shed light on the effects of avian malaria infection in the wild. 相似文献
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Man Bites Mosquito: Understanding the Contribution of Human Movement to Vector-Borne Disease Dynamics 总被引:1,自引:0,他引:1
In metropolitan areas people travel frequently and extensively but often in highly structured commuting patterns. We investigate the role of this type of human movement in the epidemiology of vector-borne pathogens such as dengue. Analysis is based on a metapopulation model where mobile humans connect static mosquito subpopulations. We find that, due to frequency dependent biting, infection incidence in the human and mosquito populations is almost independent of the duration of contact. If the mosquito population is not uniformly distributed between patches the transmission potential of the pathogen at the metapopulation level, as summarized by the basic reproductive number, is determined by the size of the largest subpopulation and reduced by stronger connectivity. Global extinction of the pathogen is less likely when increased human movement enhances the rescue effect but, in contrast to classical theory, it is not minimized at an intermediate level of connectivity. We conclude that hubs and reservoirs of infection can be places people visit frequently but briefly and the relative importance of human and mosquito populations in maintaining the pathogen depends on the distribution of the mosquito population and the variability in human travel patterns. These results offer an insight in to the paradoxical observation of resurgent urban vector-borne disease despite increased investment in vector control and suggest that successful public health intervention may require a dual approach. Prospective studies can be used to identify areas with large mosquito populations that are also visited by a large fraction of the human population. Retrospective studies can be used to map recent movements of infected people, pinpointing the mosquito subpopulation from which they acquired the infection and others to which they may have transmitted it. 相似文献
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The problem of the assessment of bioequivalence between a test formulation (T) and a reference formulation (R) of a drug using a two-way crossover experiment is considered. To claim bioequivalence between two formulations, it is required by the United States Food and Drug Administration (FDA) to demonstrate that the true ratio of means μT/μR of pharmacokinetic parameters of concern falls within some reasonable limits (e.g., (80%, 120%)) with certain assurance. A commonly used approach is to construct an approximate 90% confidence interval for μT/μR and compare it with (80%, 120%). In this paper, an exact approach according to the FDA's criteria is proposed. The proposed procedure is derived by constructing an exact confidence region (an ellipse) for (μR, μT) and comparing it with the region bounded by μT = 0.8 μR and μT = 1.2 μR. Bioequivalence is concluded if the ellipse is within the critical region. 相似文献
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《PloS one》2013,8(10)
Background
Bone metastasis represents an increasing clinical problem in advanced gastric cancer (GC) as disease-related survival improves. In literature, few data on the natural history of bone disease in GC are available.Patients and Methods
Data on clinicopathology, skeletal outcomes, skeletal-related events (SREs), and bone-directed therapies for 208 deceased GC patients with evidence of bone metastasis were statistically analyzed.Results
Median time to bone metastasis was 8 months (CI 95%, 6.125–9.875 months) considering all included patients. Median number of SREs/patient was one. Less than half of the patients (31%) experienced at least one and only 4 and 2% experienced at least two and three events, respectively. Median times to first and second SRE were 2 and 4 months, respectively. Median survival was 6 months after bone metastasis diagnosis and 3 months after first SRE. Median survival in patients who did not experience SREs was 5 months. Among patients who received zoledronic acid before the first SRE, the median time to appearance of first SRE was significantly prolonged compared to control (7 months vs 4 months for control; P: 0.0005).Conclusions
To our knowledge, this retrospective analysis is the largest multicenter study to demonstrate that bone metastases from GC are not so rare, are commonly aggressive and result in relatively early onset of SREs in the majority of patients. Indeed, our large study, which included 90 patients treated with ZOL, showed, for the first time in literature, a significant extension of time to first SRE and increase in the median survival time after diagnosis of bone metastasis. Taken together, these data may support the beneficial effects of ZOL in GC patients. 相似文献16.
《PloS one》2014,9(8)
Background
Bone is an uncommon site of metastasis in patients with advanced hepatocellular carcinoma (HCC). Therefore, there are few studies concerning the natural history of bone metastasis in patients with HCC.Patients and Methods
Data on clinicopathology, survival, skeletal-related events (SREs), and bone-directed therapies for 211 deceased HCC patients with evidence of bone metastasis were statistically analyzed.Results
The median age was 70 years; 172 patients were male (81.5%). The median overall survival was 19 months. The median time to the onset of bone metastasis was 13 months (22.2% at HCC diagnosis); 64.9% patients had multiple bone metastases. Spine was the most common site of bone metastasis (59.7%). Most of these lesions were osteolytic (82.4%); 88.5% of them were treated with zoledronic acid. At multivariate analysis, only the Child Score was significantly correlated with a shorter time to diagnosis of bone metastases (p = 0.001, HR = 1.819). The median survival from bone metastasis was 7 months. At multivariate analysis, HCC etiology (p = 0.005), ECOG performance status (p = 0.002) and treatment with bisphosphonate (p = 0.024) were associated with shorter survival after bone disease occurrence. The site of bone metastasis but not the number of bone lesions was associated with the survival from first skeletal related event (SRE) (p = 0.021) and OS (p = 0.001).Conclusions
This study provides a significant improvement in the understanding the natural history of skeletal disease in HCC patients. An early and appropriate management of these patients is dramatically needed in order to avoid subsequent worsening of their quality of life. 相似文献17.
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Fungi from the Carnegie Museum Herbarium (CM) were transferred to the New York Botanical Garden (NY) in 1981. Comprising approximately 41,000 specimens, this collection is most noteworthy for its extensive coverage of the mycota of western Pennsylvania. Biographical sketches are given of D. R. Sumstine, L. K. Henry, M. B. Knauz Overholts, and O. E. Jennings, the four main regional collectors. Two appendices are included: the first indexes the type specimens deposited in the fungus herbarium (excluding those types distributed in fungi exsiccati sets), and the second lists the sources of duplicate fungus specimens acquired by CM. 相似文献
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Nicholas C. Grassly Michael E. Ward Shirley Ferris David C. Mabey Robin L. Bailey 《PLoS neglected tropical diseases》2008,2(12)