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Paleolimnology: an important tool for effective ecosystem management   总被引:14,自引:0,他引:14  
Effective management of aquatic resources requires long-term environmental data. However, because long-term observations are rarely available, indirect proxy methods must be used to substitute for these missing historical data sets. Major advances have been made in paleolimnology over the last decade, and many of these advances can be applied directly to integrated and cost-effective assessments of aquatic ecosystem health. This commentary uses the analogy of human health to argue that paleolimnological data provide information crucial to the decision-making processes of ecosystem managers.Keynote lecture, presented at the International Sumposium on Aquatic Ecosystem Health, Waterloo, Ontario, July 23, 1990.  相似文献   

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Background

Comparative genomics, or the study of the relationships of genome structure and function across different species, offers a powerful tool for studying evolution, annotating genomes, and understanding the causes of various genetic disorders. However, aligning multiple sequences of DNA, an essential intermediate step for most types of analyses, is a difficult computational task. In parallel, citizen science, an approach that takes advantage of the fact that the human brain is exquisitely tuned to solving specific types of problems, is becoming increasingly popular. There, instances of hard computational problems are dispatched to a crowd of non-expert human game players and solutions are sent back to a central server.

Methodology/Principal Findings

We introduce Phylo, a human-based computing framework applying “crowd sourcing” techniques to solve the Multiple Sequence Alignment (MSA) problem. The key idea of Phylo is to convert the MSA problem into a casual game that can be played by ordinary web users with a minimal prior knowledge of the biological context. We applied this strategy to improve the alignment of the promoters of disease-related genes from up to 44 vertebrate species. Since the launch in November 2010, we received more than 350,000 solutions submitted from more than 12,000 registered users. Our results show that solutions submitted contributed to improving the accuracy of up to 70% of the alignment blocks considered.

Conclusions/Significance

We demonstrate that, combined with classical algorithms, crowd computing techniques can be successfully used to help improving the accuracy of MSA. More importantly, we show that an NP-hard computational problem can be embedded in casual game that can be easily played by people without significant scientific training. This suggests that citizen science approaches can be used to exploit the billions of “human-brain peta-flops” of computation that are spent every day playing games. Phylo is available at: http://phylo.cs.mcgill.ca.  相似文献   

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Behavioural biology: an effective and relevant conservation tool   总被引:1,自引:0,他引:1  
'Conservation behaviour' is a young discipline that investigates how proximate and ultimate aspects of the behaviour of an animal can be of value in preventing the loss of biodiversity. Rumours of its demise are unfounded. Conservation behaviour is quickly building a capacity to positively influence environmental decision making. The theoretical framework used by animal behaviourists is uniquely valuable to elucidating integrative solutions to human-wildlife conflicts, efforts to reintroduce endangered species and reducing the deleterious effects of ecotourism. Conservation behaviourists must join with other scientists under the multidisciplinary umbrella of conservation biology without giving up on their focus: the mechanisms, development, function and evolutionary history of individual differences in behaviour. Conservation behaviour is an increasingly relevant tool in the preservation of nature.  相似文献   

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A simple and efficient method for in vitro mutagenesis and recombination of polynucleotide sequences is reported. The method involves priming template polynucleotide(s) with random-sequence primers and extending to generate a pool of short DNA fragments which contain a controllable level of point mutations. The fragments are reassembled during cycles of denaturation, annealing and further enzyme-catalyzed DNA polymerization to produce a library of full-length sequences. Screening or selecting the expressed gene products leads to new variants with improved functions, as demonstrated by the recombination of genes encoding different thermostable subtilisins in order to obtain enzymes more stable than either parent.  相似文献   

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Axolotls can regenerate complex structures through recruitment and remodeling of cells within mature tissues. Accessing the underlying mechanisms at a molecular resolution is crucial to understand how injury triggers regeneration and how it proceeds. However, gene transformation in adult tissues can be challenging. Here we characterize the use of pseudotyped baculovirus (BV) as an effective gene transfer method both for cells within mature limb tissue and within the blastema. These cells remain competent to participate in regeneration after transduction. We further characterize the effectiveness of BV for gene overexpression studies by overexpressing Shh in the blastema, which yields a high penetrance of classic polydactyly phenotypes. Overall, our work establishes BV as a powerful tool to access gene function in axolotl limb regeneration.  相似文献   

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Small interfering RNAs (siRNAs) have become an indispensable tool for the investigation of gene functions. Most existing siRNA design tools were trained on datasets assembled from confined origins, incompatible with the diverse siRNA laboratory practice to which these tools will ultimately be applied. We have performed an updated analysis using the disjunctive rule merging (DRM) approach on a large and diverse dataset compiled from siRecords, and implemented the resulting rule sets in siDRM, a new online siRNA design tool. siDRM also implements a few high-sensitivity rule sets and fast rule sets, links to siRecords, and uses several filters to check unwanted detrimental effects, including innate immune responses, cell toxic effects and off-target activities in selecting siRNAs. A performance comparison using an independent dataset indicated that siDRM outperforms 19 existing siRNA design tools in identifying effective siRNAs.  相似文献   

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BASF has developed a Metabolomics database (MetaMap(?) Tox) containing approximately 500 data rich chemicals, agrochemicals and drugs. This metabolome-database has been built based upon 28-day studies in rats (adapted to OECD 407 guideline) with blood sampling and metabolic profiling after 7, 14 and 28 days of test substance treatment. Numerous metabolome patterns have been established for different toxicological targets (liver, kidney, thyroid, testes, blood, nervous system and endocrine system) which are specific for different toxicological modes of action. With these patterns early detection of toxicological effects and the underlying mechanism can now be obtained from routine studies. Early recognition of toxicological mode of action will help to develop new compounds with a more favourable toxicological profile and will also help to reduce the number of animal studies necessary to do so. Thus this technology contributes to animal welfare by means of reduction through refinement (2R), but also has potential as a replacement method by analyzing samples from in vitro studies. With respect to the REACH legislation for which a large number of animal studies will need to be performed, one of the most promising methods to reduce the number of animal experiments is grouping of chemicals and read-across to those which are data rich. So far mostly chemical similarity or QSAR models are driving the selection process of chemical grouping. However, "omics" technologies such as metabolomics may help to optimize the chemical grouping process by providing biologically based criteria for toxicological equivalence. "From QSAR to QBAR" (quantitative biological activity relationship).  相似文献   

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Approximately 1,000 volunteers assessed the presence of invasive (Carcinus maenas and Hemigrapsus sanguineus) and native crabs within the intertidal zone of seven coastal states of the US, from New Jersey to Maine. Identification of crab species and determination of the gender of the observed crabs was documented at all 52 sites across a 725-km coastal transect. Using quantitative measures of accuracy of data collected by citizen scientists, a significant predictor of a volunteer’s ability was determined and eligibility criteria were set. Students in grade three and seven had the ability to differentiate between species of crabs with over 80% and 95% accuracy, respectively. Determination of gender of the crabs was more challenging and accuracy exceeded 80% for seventh grade students, while 95% accuracy was found for students with at least 2 years of university education. We used the data collected by citizen scientists to create a large-scale standardized database of the distribution and abundance of the native and invasive crabs. Hemigrapsus sanguineus dominated the rocky intertidal zone from Sandy Hook, New Jersey to Boston Harbor, Massachusetts while C. maenas dominated the northern extent of the sampled coastline. A citizen scientist of this monitoring network detected a range expansion of H. sanguineus. We identified obstacles to creating a national monitoring network and proposed recommendations that addressed these issues.  相似文献   

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Biodiversity and Conservation - In 2012, a new volunteer-based recording scheme for vascular plants was launched in the Netherlands. Its purpose is to track the changes in the number of occupied...  相似文献   

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Complex surveillance problems are common in biosecurity, such as prioritizing detection among multiple invasive species, specifying risk over a heterogeneous landscape, combining multiple sources of surveillance data, designing for specified power to detect, resource management, and collateral effects on the environment. Moreover, when designing for multiple target species, inherent biological differences among species result in different ecological models underpinning the individual surveillance systems for each. Species are likely to have different habitat requirements, different introduction mechanisms and locations, require different methods of detection, have different levels of detectability, and vary in rates of movement and spread. Often there is a further challenge of a lack of knowledge, literature, or data, for any number of the above problems. Even so, governments and industry need to proceed with surveillance programs which aim to detect incursions in order to meet environmental, social and political requirements. We present an approach taken to meet these challenges in one comprehensive and statistically powerful surveillance design for non-indigenous terrestrial vertebrates on Barrow Island, a high conservation nature reserve off the Western Australian coast. Here, the possibility of incursions is increased due to construction and expanding industry on the island. The design, which includes mammals, amphibians and reptiles, provides a complete surveillance program for most potential terrestrial vertebrate invaders. Individual surveillance systems were developed for various potential invaders, and then integrated into an overall surveillance system which meets the above challenges using a statistical model and expert elicitation. We discuss the ecological basis for the design, the flexibility of the surveillance scheme, how it meets the above challenges, design limitations, and how it can be updated as data are collected as a basis for adaptive management.  相似文献   

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Fluorescence spectroscopy Excitation Emission Matrix (EEM) measurements were applied on human blood plasma samples from a case control study on colorectal cancer. Samples were collected before large bowel endoscopy and included patients with colorectal cancer or with adenomas, and from individuals with other non malignant findings or no findings (N = 308). The objective of the study was to explore the possibilities for applying fluorescence spectroscopy as a tool for detection of colorectal cancer. Parallel Factor Analysis (PARAFAC) was applied to decompose the fluorescence EEMs into estimates of the underlying fluorophores in the sample. Both the pooled score matrix from PARAFAC, holding the relative concentrations of the derived components, and the raw unfolded spectra were used as basis for discrimination models between cancer and the various controls. Both methods gave test set validated sensitivity and specificity values around 0.75 between cancer and controls, and poor discriminations between the various controls. The PARAFAC solution gave better options for analyzing the chemical mechanisms behind the discrimination, and revealed a blue shift in tryptophan emission in the cancer patients, a result that supports previous findings. The present findings show how fluorescence spectroscopy and chemometrics can help in cancer diagnostics, and with PARAFAC fluorescence spectroscopy can be a potential metabonomic tool.  相似文献   

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Phytochemistry Reviews - Capsaicinoids (CAPs) are compounds synthesized and accumulated exclusively in pepper fruits. They are known as health-promoting compounds, and upbringing approaches to...  相似文献   

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