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The Asia‐Pacific Biodiversity Observation Network (APBON) was launched in 2009, in response to the establishment of the Biodiversity Observation Network under the Group on Earth Observations in 2008. APBON's mission is to increase exchange of knowledge and know‐how between institutions and researchers concerning biodiversity science research in the Asia‐Pacific (AP) region and thereby contribute to evidence‐based decision‐making and policy‐making. Here we summarize APBON activities and achievements in its first 10 years. We review how APBON has developed networks, facilitated communication for sharing knowledge, and built capacity of researchers and stakeholders through workshops and publications as well as discuss the network plan. Key findings by APBON members include descriptions of species new to science, mapping tropical forest cover change, evaluating impacts of hydropower dams and climate change on fish species diversity in the Mekong, and mapping "Ecologically and Biologically Significant Areas" in the oceans. APBON has also contributed to data collection, sharing, analysis, and synthesis for regional and global biodiversity assessment. A highlight was contributing to the "Intergovernmental Science‐Policy Platform on Biodiversity and Ecosystem Services" regional report. New strategic plans target the development of national‐level BONs and interdisciplinary research to address the data and knowledge gaps and increase data accessibility for users and for meeting societal demands. Strengthening networks in AP region and capacity building through APBON meetings will continue. By promoting monitoring and scientific research and facilitating the dialogue with scientists and policymakers, APBON will contribute to the implementation of conservation and sustainable use of biodiversity in the entire AP region. [ABSTRACT FROM AUTHOR]

Summary: Diplonemids are considered marine protists and have been reported among the most abundant and diverse eukaryotes in the world oceans. Recently we detected the presence of freshwater diplonemids in Japanese deep freshwater lakes. However, their distribution and abundances in freshwater ecosystems remain unknown. We assessed abundance and diversity of diplonemids from several geographically distant deep freshwater lakes of the world by amplicon‐sequencing, shotgun metagenomics and catalysed reporter deposition‐fluorescent in situ hybridization (CARD‐FISH). We found diplonemids in all the studied lakes, albeit with low abundances and diversity. We assembled long 18S rRNA sequences from freshwater diplonemids and showed that they form a new lineage distinct from the diverse marine clades. Freshwater diplonemids are a sister‐group to a marine clade, which are mainly isolates from coastal and bay areas, suggesting a recent habitat transition from marine to freshwater habitats. Images of CARD‐FISH targeted freshwater diplonemids suggest they feed on bacteria. Our analyses of 18S rRNA sequences retrieved from single‐cell genomes of marine diplonemids show they encode multiple rRNA copies that may be very divergent from each other, suggesting that marine diplonemid abundance and diversity both have been overestimated. These results have wider implications on assessing eukaryotic abundances in natural habitats by using amplicon‐sequencing alone. [ABSTRACT FROM AUTHOR]

Summary: Metagenomics has dramatically expanded the known virosphere, but freshwater viral diversity and their ecological interaction with hosts remain poorly understood. Here, we conducted a metagenomic exploration of planktonic dsDNA prokaryotic viruses by sequencing both virion (<0.22 μm) and cellular (0.22–5.0 μm) fractions collected spatiotemporally from a deep freshwater lake (Lake Biwa, Japan). This simultaneously reconstructed 183 complete (i.e., circular) viral genomes and 57 bacterioplankton metagenome‐assembled genomes. Analysis of metagenomic read coverage revealed vertical partitioning of the viral community analogous to the vertically stratified bacterioplankton community. The hypolimnetic community was generally stable during stratification, but occasionally shifted abruptly, presumably due to lysogenic induction. Genes involved in assimilatory sulfate reduction were encoded in 20 (10.9%) viral genomes, including those of dominant viruses, and may aid viral propagation in sulfur‐limited freshwater systems. Hosts were predicted for 40 (21.9%) viral genomes, encompassing 10 phyla (or classes of Proteobacteria) including ubiquitous freshwater bacterioplankton lineages (e.g., Ca. Fonsibacter and Ca. Nitrosoarchaeum). Comparison with viral genomes derived from published metagenomes revealed viral phylogeographic connectivity in geographically isolated habitats. Notably, analogous to their hosts, actinobacterial viruses were among the most diverse, ubiquitous and abundant viral groups in freshwater systems, with potential high lytic activity in surface waters. [ABSTRACT FROM AUTHOR]

Intramuscular adipose tissue ( IMAT) formation is a hallmark of marbling in cattle. IMAT is considered to originate from skeletal muscle progenitor cells with adipogenic potential. However, the mechanism involved in IMAT formation from these progenitor cells in vivo remains unclear. In the present study, among the growth factors tested, which were known to be expressed in skeletal muscle, we found only basic fibroblast growth factor ( bFGF) has a pro-adipogenic effect on skeletal muscle derived adipogenic progenitor clone, 2G11 cells. Pre-exposure of 2G11 cells to bFGF did not affect initial gene expressions of CCAAT/enhancer-binding protein ( C/ EBP)β and C/ EBPδ, while resulting in an enhancement of subsequent expressions of C/ EBPα and proliferator-activated receptor gamma ( PPARγ) during adipogenesis, indicating that bFGF is acting on the transcriptional regulation of C/ EBPα and PPARγ. In addition, the effect of bFGF is mediated via two types of FGF receptor ( FGFR) isoforms: FGFR1 and FGFR2 IIIc, and both receptors are prerequisite for bFGF to express its pro-adipogenic effect. These results suggest that bFGF plays an important role as a key trigger of IMAT formation in vivo. [ABSTRACT FROM AUTHOR]

The primary goal of the 60th anniversary symposium of the Ecological Society of Japan (ESJ) was to re-examine the role of the Society. The first of five lectures, ' Development of Long- term Ecological Research in Japan,' discussed the increasingly important role of long-term and networked research studies. Ecological research in Asia faces many challenges, because Asia features natural and anthropogenic landscapes with highly diverse ecosystems. ' Developing Strategies of the Ecological Society of Japan for Worldwide Societies of Ecology with Special Reference to Strategies for Asia' emphasized the role of ESJ in promoting ecological research and outreach in Asia. Ecosystem sustainability is a key issue in both the theory and practice of ecosystem management. A framework concept of an environmental and biodiversity cycle was proposed in the session ' Linking Community and Ecosystem Dynamics' for understanding the mechanisms driving the sustainability of ecosystems. Ecosystem services are essential aspects of land use and conservation planning and management. ' Integrating Models of Ecosystem Services and Land Use Changes' reviewed recently-developed models that simulate patterns of land-use change and analyze its effects on ecosystem services and also recommended future directions for collaboration among researchers. ' Disaster Resilience and Coastal Ecology' highlighted the contributions of ecologists to evaluating the resilience of damaged coastal ecosystems and provided sound proposals to local communities and governments for rehabilitation plans. The past achievements and future directions of ESJ were discussed by the panelists and the audience in ' Past and Future of the Ecological Society of Japan.' [ABSTRACT FROM AUTHOR]

ABSTRACT Introduction: The expression of secreted protein acidic and rich in cysteine (SPARC) in skeletal muscle decreases with age. Here, we examined the role of SPARC in skeletal muscle by reducing its expression. Methods: SPARC expression was suppressed by introducing short interfering RNA (siRNA) into mouse tibialis anterior muscle. Myofiber diameter, atrogin1, and muscle RING-finger protein 1 (MuRF1) expression, and tumor necrosis factor-α (TNFα) and transforming growth factor-β (TGFβ) signaling were then analyzed. Results: Reduced SPARC expression caused decreases in the diameter of myofibers, especially fast-type ones, accompanied by upregulation of atrogin1, but not MuRF1, at 10 days after siRNA transfection. The expression of TNFα and TGFβ and the phosphorylation status of p38 were not affected by SPARC knockdown, whereas Smad3 phosphorylation was increased at 2 days after siRNA transfection. Conclusions: The loss of SPARC not only upregulates atrogin1 expression but also enhances TGFβ signaling, which may in turn cause muscle atrophy. Muscle Nerve 48:791-799, 2013 [ABSTRACT FROM AUTHOR]

Intramuscular adipose tissue ( IMAT) is observed in some skeletal muscle pathologies. IMAT is implicated not only in the disorders of muscle contraction, but also of metabolism and insulin sensitivity due to its nature as a secretary organ. Several studies indicate the presence of cells with adipogenic potential in skeletal muscle. However, the mechanism of fate specification that triggers these cells to enter an adipogenic program in vivo remains to be solved. In the present study, we examined whether activation of the adipogenic program of muscle-resident cells precedes their proliferation upon muscle injury. For this purpose, muscle injury was induced by injecting bupivacaine ( BPVC) to excised skeletal muscle ex vivo. Cells isolated from ex vivo BPVC-treated muscle exhibited higher adipogenic potential than those from saline-treated muscle. Pre-plating exposure of skeletal muscle cells to basic fibroblast growth factor ( bFGF) mimicked the effect of ex vivo BPVC-treatment, suggesting that bFGF released from extracellular matrix in response to muscle injury activates their adipogenic program. Interestingly, the number of myotubes were significantly reduced in the culture from BPVC-treated muscle, suggesting that adipocytes negatively regulate myogenesis. [ABSTRACT FROM AUTHOR]

We consider the following simple network design problem. The input consists of n weighted nodes, and the output is an edge-weighted connected network such that the total weight of the edges incident to a node is at least the given weight of the node. We aim to design the cheapest connected network; that is, the reachability of the network should be guaranteed, and the network is better if its total weight is less. In this article, we first show an efficient algorithm that produces an optimal network with minimum weight. The algorithm runs in linear time, and the resulting network contains at most n edges, where n is the number of nodes. To construct a connected network, at least n - 1 edges are required. However, the algorithm sometimes outputs n edges. Next, we aim to minimize not only the weight but also the number of edges. That is, for given n weighted nodes, we aim to design a cheapest tree. Then, the problem becomes \documentclass{article}\usepackage{mathrsfs, amsmath, amssymb}\pagestyle{empty}\begin{document}\begin{align*}\mathcal{N}\mathcal{P}\end{align*} \end{document} -complete. We also propose efficient approximation algorithms for constructing a cheapest tree. © 2013 Wiley Periodicals, Inc. NETWORKS, 2013 [ABSTRACT FROM AUTHOR]

ABSTRACT The present study describes the isolation, cloning and characterization of adipogenic progenitor cells from rat skeletal muscle. Among the obtained 10 clones, the most highly adipogenic progenitor, 2G11 cells, were further characterized. In addition to their adipogenicity, 2G11 cells retain myogenic potential as revealed by formation of multinucleated myotubes when co-cultured with myoblasts. 2G11 cells were resistant to an inhibitory effect of basic fibroblast growth factor on adipogenesis, while adipogenesis of widely used preadipogenic cell line, 3T3-L1 cells, was suppressed almost completely by the same treatment. In vivo transplantation experiments revealed that 2G11 cells are able to possess both adipogenicity and myogenicity in vivo. These results indicate the presence of bipotent progenitor cells in rat skeletal muscle, and suggest that such cells may contribute to ectopic fat formation in skeletal muscle. [ABSTRACT FROM AUTHOR]

Food-chain length (FCL) in ecosystems has been studied extensively, and numerous hypotheses to predict FCL, productivity, ecosystem size, and productive space have been proposed. For example, the productivity hypothesis suggests that resource availability limits FCL, whereas the productive-space hypothesis predicts that per-unit-size resource availability and ecosystem size equally limit FCL. However, previous studies have only measured total productivity to test FCL and have never tested the impact of resource availability within a system on FCL. Therefore, we estimated FCL in 15 ponds using stable isotope techniques to test the most common hypotheses for predicting FCL. We also measured total productivity, pond volume (ecosystem size), and edible microalgal carbon (resource availability) in each pond. We found that productive-space (edible carbon+pond volume) was the best model to predict FCL, and FCL was significantly correlated with edible carbon and pond volume. However, factors such as total productivity did not directly predict FCL of the ponds. Therefore, our results suggest that both resource availability and ecosystem size predict FCL in pond ecosystems and play significant roles in maintaining longer FCLs. Furthermore, the productive-space hypothesis appears to be particularly important for determining the FCL of ponds. [ABSTRACT FROM AUTHOR]

A realizer of a triangulated plane graph G is a partition of interior edges of G, satisfying some conditions. The realizer has many applications, including graph drawing algorithms. Given a triangulated plane graph G, no algorithm to generate all realizers of G is known. In this paper, we first give an algorithm to generate all realizers. We first define a left canonical ordering for the vertices of an input graph, then show that there is a bijection between the left canonical orderings and realizers. Based on the bijection, we give an algorithm to generate all realizers. The algorithm generates each realizer in O(n) time without duplications, where n is the number of vertices in the graph. © 2006 Wiley Periodicals, Inc. Electron Comm Jpn Pt 2, 89(7): 40–47, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjb.20276 [ABSTRACT FROM AUTHOR]

A plane drawing of a plane graph is called a rectangular drawing if every face (including the outer face) is a rectangle. An algorithm to generate all based rectangular drawings with maximum degree three is known. In this paper by generalizing the algorithm we give a simple algorithm to generate all based rectangular drawings having n faces without the degree constraint. The algorithm generates without duplications all rectangular drawings having exactly n faces in O(n) time per drawing. By modifying the algorithm we give three more algorithms to generate all rectangular drawings with certain properties. Those algorithms use O(n) space in total. © 2004 Wiley Periodicals, Inc. Syst Comp Jpn, 35(4): 1–8, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/scj.10563 [ABSTRACT FROM AUTHOR]

This paper introduces a new edge-coloring of graphs called "fg-edge-coloring." It is used to color all edges of a graph so that at most f(v) edges of a same color exist among edges incident at each vertex v, and at most p(vw) edges among multiple edges joining each pair of vertices V and w. Various upper bounds are given for the fg-chromatic index, that is, the minimum number of colors required for fg-coloring. One of them is a generalization of the upper bounds for the ordinary edge-coloring by Vizing and Hakimi-Kariv. The proof is constructive and yields a polynomial time algorithm to determine fg-coloring using colors no more than the upper bound. [ABSTRACT FROM AUTHOR]

A decrease in the abundance of virus-like particles (VLP) by heterotrophic nanoflagellates (HNF) was examined using size-fractionated water samples taken from a hypereutrophic pond in December 1999, and in March and July 2000. We recorded a considerable decrease in the abundance of VLP in the 5.0 µm filtrate relative to the 0.2–0.8 µm filtrates. Decrease rates of VLP were reduced in a parallel 5.0 µm filtrate treated with cycloheximide. The loss rates of VLP in 5.0 µm filtrate varied in each experiment, and a high rate of loss was found when the growth rate of HNF was high. These results suggested that HNF consumed the VLP and that HNF is an important factor for decreasing viral abundance in freshwater environments. [ABSTRACT FROM AUTHOR]