Genome sequencing has created unprecedented opportunities for natural-product discovery and new insight into the diversity and distributions of natural-product biosynthetic gene clusters (BGCs). ...These gene collectives are highly evolved for horizontal exchange, thus providing immediate opportunities to test the effects of small molecules on fitness. The marine actinomycete genus Salinispora maintains extraordinary levels of BGC diversity and has become a useful model for studies of secondary metabolism. Most Salinispora BGCs are observed infrequently, resulting in high population-level diversity while conforming to constraints associated with maximum genome size. Comparative genomics is providing a mechanism to assess secondary metabolism in the context of evolution and evidence that some products represent ecotype-defining traits while others appear selectively neutral.
Catalyst discovery is increasingly relying on computational chemistry, and many of the computational tools are currently being automated. The state of this automation and the degree to which it may ...contribute to speeding up development of catalysts are the subject of this Perspective. We also consider the main challenges associated with automated catalyst design, in particular the generation of promising and chemically realistic candidates, the tradeoff between accuracy and cost in estimating the catalytic performance, the opportunities associated with automated generation and use of large amounts of data, and even how to define the objectives of catalyst design. Throughout the Perspective, we take a cross-disciplinary approach and evaluate the potential of methods and experiences from fields other than homogeneous catalysis. Finally, we provide an overview of software packages available for automated in silico design of homogeneous catalysts.
There has been great interest in developing methodologies that are capable of dealing with imprecision and uncertainty. The large amount of research currently being carried out in fuzzy and rough ...sets is representative of this. Many deep relationships have been established, and recent studies have concluded as to the complementary nature of the two methodologies. Therefore, it is desirable to extend and hybridize the underlying concepts to deal with additional aspects of data imperfection. Such developments offer a high degree of flexibility and provide robust solutions and advanced tools for data analysis. Fuzzy-rough set-based feature (FS) selection has been shown to be highly useful at reducing data dimensionality but possesses several problems that render it ineffective for large datasets. This paper proposes three new approaches to fuzzy-rough FS-based on fuzzy similarity relations. In particular, a fuzzy extension to crisp discernibility matrices is proposed and utilized. Initial experimentation shows that the methods greatly reduce dimensionality while preserving classification accuracy.
When information is limited or costly, agents are unable to engage in optimal arbitrage. Excess price dispersion across markets can arise, and goods may not be allocated efficiently. In this setting, ...information technologies may improve market performance and increase welfare. Between 1997 and 2001, mobile phone service was introduced throughout Kerala, a state in India with a large fishing industry. Using microlevel survey data, we show that the adoption of mobile phones by fishermen and wholesalers was associated with a dramatic reduction in price dispersion, the complete elimination of waste, and near-perfect adherence to the Law of One Price. Both consumer and producer welfare increased.
Background: Medication overuse headache is a common condition with a population‐based prevalence of more than 1–2%. Treatment is based on education, withdrawal treatment (detoxification), and ...prophylactic treatment. It also includes management of withdrawal headache.
Aims: This guideline aims to give treatment recommendations for this headache.
Materials and methods: Evaluation of the scientific literature.
Results: Abrupt withdrawal or tapering down of overused medication is recommended, the type of withdrawal therapy is probably not relevant for the outcome of the patient. However, inpatient withdrawal therapy is recommended for patients overusing opioids, benzodiazepine, or barbiturates. It is further recommended to start individualized prophylactic drug treatment at the first day of withdrawal therapy or even before. The only drug with moderate evidence for the prophylactic treatment in patients with chronic migraine and medication overuse is topiramate up to 200 mg. Corticosteroids (at least 60 mg prednisone or prednisolone) and amitriptyline (up to 50 mg) are possibly effective in the treatment of withdrawal symptoms. Patients after withdrawal therapy should be followed up regularly to prevent relapse of medication overuse.
Discussion and conclusion: Medication overuse headache can be treated according to evidence‐based recommendations.
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Hidden formaldehyde in e-cigarette aerosols Jensen, R Paul; Luo, Wentai; Pankow, James F ...
The New England journal of medicine,
2015-Jan-22, Letnik:
372, Številka:
4
Journal Article
Wildfire plays an important role in ecosystem dynamics, land management, and global processes. Understanding the dynamics associated with wildfire, such as risks, spatial distribution, and effects is ...important for developing a clear understanding of its ecological influences. Remote sensing technologies provide a means to study fire ecology at multiple scales using an efficient and quantitative method. This paper provides a broad review of the applications of remote sensing techniques in fire ecology. Remote sensing applications related to fire risk mapping, fuel mapping, active fire detection, burned area estimates, burn severity assessment, and post-fire vegetation recovery monitoring are discussed. Emphasis is given to the roles of multispectral sensors, lidar, and emerging UAS technologies in mapping, analyzing, and monitoring various environmental properties related to fire activity. Examples of current and past research are provided, and future research trends are discussed. In general, remote sensing technologies provide a low-cost, multi-temporal means for conducting local, regional, and global-scale fire ecology research, and current research is rapidly evolving with the introduction of new technologies and techniques which are increasing accuracy and efficiency. Future research is anticipated to continue to build upon emerging technologies, improve current methods, and integrate novel approaches to analysis and classification.
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