Genomic sequence data have revealed the presence of a large fraction of putatively silent biosynthetic gene clusters in the genomes of actinomycetes that encode for secondary metabolites, which are not detected under standard fermentation conditions. This review focuses on the effects of biological (co-cultivation), chemical, as well as molecular elicitation on secondary metabolism in actinomycetes. Our review covers the literature until June 2014 and exemplifies the diversity of natural products that have been recovered by such approaches from the phylum Actinobacteria.

Global warming and the associated climate changes are predictable. They are enhanced by burning of fossil fuels and the emission of huge amounts of CO 2 gas which resulted in greenhouse effect. It is expected that the average global temperature will increase with 2-5°C in the next decades. As a result, the earth will exhibit marked climatic changes characterized by extremer weather events in the coming decades, such as the increase in temperature, rainfall, summertime, droughts, more frequent and stronger tornadoes and hurricanes. Epidemiological disease cycle includes host, pathogen and in certain cases intermediate host/vector. A complex mixture of various environmental conditions (e.g. temperature and humidity) determines the suitable habitat/ecological niche for every vector host. The availability of suitable vectors is a precondition for the emergence of vector-borne pathogens. Climate changes and global warming will have catastrophic effects on human, animal and environmental ecosystems. Pathogens, especially neglected tropical disease agents, are expected to emerge and re-emerge in several countries including Europe and North America. The lives of millions of people especially in developing countries will be at risk in direct and indirect ways. In the present review, the role of climate changes in the spread of infectious agents and their vectors is discussed. Examples of the major emerging viral, bacterial and parasitic diseases are also summarized.

Molecular docking reveals the potential of Salvadora persica flavonoids to inhibit COVID-19 virus main protease.

The problem of finding the relative position and orientation between the reference frames of a link-mounted sensor and the link has been formulated as a kinematic equation of the form H l H x = H x H c in terms of homogeneous transformation matrices by Shiu and Ahmad (1987). In this article, normal ized quaternions (Euler parameters) are used to transform the kinematic equation into two simple and structured linear systems with rank-deficient coefficient matrices. Closed-form solutions to these systems are derived using the generalized inverse method with singular-value decomposition analysis. To obtain a unique solution, two distinct robot movements are required. This leads to an overdetermined system of equations. A criterion for selecting the independent set of equations is developed. A set of closed-form formulae for the solution of these equations are derived. The selection crite rion and the solution formulae can be easily incorporated in application programs that require the calculation of the rela tive position and orientation of the sensor.

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Modular Neural Networks (MNNs) is a rapidly growing field in artificial Neural Networks (NNs) research. This paper surveys the different motivations for creating MNNs: biological, psychological, hardware, and computational. Then, the general stages of MNN design are outlined and surveyed as well, viz., task decomposition techniques, learning schemes and multi-module decision-making strategies. Advantages and disadvantages of the surveyed methods are pointed out, and an assessment with respect to practical potential is provided. Finally, some general recommendations for future designs are presented.

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