Termites in the woodwork

Termites eat and digest wood, but how do they do it? Combining advanced genomics and proteomics techniques, researchers have now shown that microbes found in the termites' hindguts possess just the right tools. Most animals, from insects to mammals, carry complex communities of microbes in their digestive tracts. In the case of wood-eating termites, these gut microbes are particularly important: they are thought to provide most of the capabilities needed for efficient digestion of wood, which is otherwise a largely inaccessible food source. They also help to compensate for the paucity of some nutrients in wood, for example by fixing atmospheric nitrogen, and they synthesize essential amino acids and other compounds for their hosts [1, 2]. Despite their importance, relatively little is known about gut microbes in termites. This is partly because gut microbes are often difficult to grow in pure culture (as is the case for most microbes sampled from natural environments). Furthermore, a single termite can harbor a very complex assemblage of hundreds of different microbial lineages, whose members may vary widely in terms of abundance and growth rates. Without access to cultivated strains, researchers have to rely on so-called 'cultivation-independent' molecular techniques to analyze such communities. A clever combination of these techniques has now been applied to a section of the termite hindgut, aiming to identify molecular tools used by the microbes in this compartment to degrade wood [3]. Here, we review the procedures and results of this study, and discuss insights into the biological system as well as implications for the generation of biofuels

Preferential attachment in the protein network evolution

The Saccharomyces cerevisiae protein-protein interaction map, as well as many natural and man-made networks, shares the scale-free topology. The preferential attachment model was suggested as a generic network evolution model that yields this universal topology. However, it is not clear that the model assumptions hold for the protein interaction network. Using a cross genome comparison we show that (a) the older a protein, the better connected it is, and (b) The number of interactions a protein gains during its evolution is proportional to its connectivity. Therefore, preferential attachment governs the protein network evolution. The evolutionary mechanism leading to such preference and some implications are discussed.Comment: Minor changes per referees requests; to appear in PR

Pengembangan Bahan Ajar IPA Integratif Dengan Menggunakan Strategi Inkuiri Tentang Konsep Struktur Tumbuhan

The purpose of this research is to develop Integrative Natural Science Teaching Material model series of learning activities using the strategy of Inqury as a form of strengthening the understanding of the the plant structure concept material. This research was conducted with a qualitative approach through a cycle of Research and Development ( R & D ) and the stages of the reseach process ; collecting data , develop and validate a product , revision, individual testing, limited and field testing. The study result concluded that the Integrative Natural Science Teaching Material through directinteractionwith the environment by using the strategy of inqury can be responded and absorbed the concept of understanding the material by learners with easy and fun, so that, the concept of mastery leraning can be achieved

Duplication-divergence model of protein interaction network

We show that the protein-protein interaction networks can be surprisingly well described by a very simple evolution model of duplication and divergence. The model exhibits a remarkably rich behavior depending on a single parameter, the probability to retain a duplicated link during divergence. When this parameter is large, the network growth is not self-averaging and an average vertex degree increases algebraically. The lack of self-averaging results in a great diversity of networks grown out of the same initial condition. For small values of the link retention probability, the growth is self-averaging, the average degree increases very slowly or tends to a constant, and a degree distribution has a power-law tail.Comment: 8 pages, 13 figure

Sampling properties of random graphs: the degree distribution

We discuss two sampling schemes for selecting random subnets from a network: Random sampling and connectivity dependent sampling, and investigate how the degree distribution of a node in the network is affected by the two types of sampling. Here we derive a necessary and sufficient condition that guarantees that the degree distribution of the subnet and the true network belong to the same family of probability distributions. For completely random sampling of nodes we find that this condition is fulfilled by classical random graphs; for the vast majority of networks this condition will, however, not be met. We furthermore discuss the case where the probability of sampling a node depends on the degree of a node and we find that even classical random graphs are no longer closed under this sampling regime. We conclude by relating the results to real {\it E.coli} protein interaction network data.Comment: accepted for publication in Phys.Rev.

Analisis Musik Dendo Dayak Kanayatn di Kecamatan Mandor Kabupaten Landak

The purpose of this research is to analysis of composition of Gadobong was patterns, Agukng and Tawak-tawak as well as an analysis of Dau melody in Dendo music of Kanayatn tribe Mandor Subdistrict Landak District of West Kalimantan. Data were analyzed qualitatively. Dendo music is a music that be functioning as a companion in a traditional rituals for healing the sick (Babore) and Nyaru\u27 Sumangat. Wasp on Dendo music composition includes three instruments are Gadobong instrument amounted to one player, Agukng and Tawak-tawak amounted to one player, and Dau amounted two player. Dendo musical composition analysis includes the element of music, the rhythm patterns, melody, tone, time signatures, notation, and tempo. This Dendo music can be used as a lesson plan in teaching and learning activities and teaching theory and also the practical work in Culture and Skill Art (Seni Budaya dan Keterampilan) lesson

Spectral Measures of Bipartivity in Complex Networks

We introduce a quantitative measure of network bipartivity as a proportion of even to total number of closed walks in the network. Spectral graph theory is used to quantify how close to bipartite a network is and the extent to which individual nodes and edges contribute to the global network bipartivity. It is shown that the bipartivity characterizes the network structure and can be related to the efficiency of semantic or communication networks, trophic interactions in food webs, construction principles in metabolic networks, or communities in social networks.Comment: 16 pages, 1 figure, 1 tabl

A format for phylogenetic placements

We have developed a unified format for phylogenetic placements, that is, mappings of environmental sequence data (e.g. short reads) into a phylogenetic tree. We are motivated to do so by the growing number of tools for computing and post-processing phylogenetic placements, and the lack of an established standard for storing them. The format is lightweight, versatile, extensible, and is based on the JSON format which can be parsed by most modern programming languages. Our format is already implemented in several tools for computing and post-processing parsimony- and likelihood-based phylogenetic placements, and has worked well in practice. We believe that establishing a standard format for analyzing read placements at this early stage will lead to a more efficient development of powerful and portable post-analysis tools for the growing applications of phylogenetic placement.Comment: Documents version 3 of the forma