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• This review states the isolation, culture, characterization and application of OMF. • Major bottlenecks of traditional identification of OMF and its elucidation are discussed. • States the application OMF for bio-hardening and growth promotion of seedlings. • Provides insights for mass cultivation and conservation of orchids. In nature all orchids develop a mutualistic association with specialized group of fungi called orchid mycorrhiza. In natural environment, orchids are exclusively reliant on mycorrhizal fungi for seed germination, establishment, growth and development. In the early developmental stages, all orchids are mycoheterotrophic, and in most cases the association subsists throughout their lifespan. The significance of orchid mycorrhizal fungi (OMF) for seed germination, nourishment, growth promotion, and survival has been established more than a century ago and tremendous advancements were made in recent decades. Till date, understanding the mode of interaction between orchids and mycorrhizal fungi and determining the architecture of interaction networks are major challenges in ecology and evolutionary biology. The development of molecular techniques has empowered us to unscramble the fungal diversity comprised in the symbiosis and has facilitated us to overcome the difficulties associated with the conventional identification of OMF and orchid-fungal interactions. In addition, the application of modern biotechnological approaches resolved many controversial issues of OMF. Recently, OMF are used for biological hardening and growth promotion of in vitro raised seedlings, early flowering and quality improvement of flowers, and diseases and pests management. The aim of this communication is to update and summarize orchid mycorrhizal research including isolation, culture, and characterization of OMF, understanding the mechanisms of orchid-fungus symbiosis, and application of OMF in seed germination, growth promotion, and survival of asymbiotically raised seedlings and conservation of orchids. This appraisal will convey valuable insights to orchidologists engaged in biology, propagation, and conservation of orchids. [ABSTRACT FROM AUTHOR]

The Orchidaceae are globally distributed and represent a diverse lineage of obligate mycotrophic plants. Given their dependence on symbiotic fungi for germination and/or plant development, fungal community structure in substrates is expected to influence the distribution and persistence of orchid species. Yet, simultaneous characterization of orchid mycorrhizal fungal (OMF) communities in roots and in soil is rarely reported. To explain the co-distributions of OMF in roots, orchid-occupied, and bulk soil, we characterized mycorrhizal fungi associated with Platanthera praeclara over multiple years across its entire natural distribution within the North American tallgrass prairie. Root derived OMF communities included 24 Ceratobasidiaceae and 7 Tulasnellaceae operational taxonomic units (OTUs) though the orchid exhibited high spatio-temporal specificity toward a single Ceratobasidiaceae OTU, which was strongly stable across population sizes and phenological stages of the sampled individuals. The preferred OMF OTUs were primarily restricted to orchid-occupied locations while infrequent or absent in bulk soil. Variation in soil OMF assemblies was explained most by soil moisture, magnesium, manganese, and clay. In this first study of coupled root and soil OMF communities across a threatened grassland ecosystem, we report a strong relationship, further nuanced by soil chemistry, between a rare fungus and a rare orchid. [ABSTRACT FROM AUTHOR]

Abstract: We present the Lab Wiki, an executable paper platform primarily designed but not limited to networking experiment-based research. The LabWiki leverages the current state of the art tools for the orchestration of experiments in the networking community and propose a new approach to execute and reproduce experiments. We demonstrate the usability of the LabWiki through an example at the boundary between network and high performance computing researches. [Copyright &y& Elsevier]

An area of heightened interest after the 1994 Northridge earthquake was the seismic ductility of steel moment frame connections. Work by the Federal Emergency Management Agency (FEMA) and Seismic Analysis Code (SAC), American Institute of Steel Construction Inc. (AISC) and many others over the last few years has expanded knowledge in a number of areas and provided a set of new and modified connection details for improved seismic performance. Some of the more popular connection types, such as the new reduced beam section (RBS) detail, will be described more fully later.Questions about the performance characteristics of the k-area region of wide-flange steel shapes were also addressed by AISC. Such regions contain variations in mechanical properties due to cold forming during the mill straightening process. Localized material properties in this region, such as strain hardening, yield and ultimate strengths, ductility and toughness are known to become altered. An extensive research effort sponsored by AISC was initiated to study the effects and performance of the k-area region is nearing completion. Such studies, conducted at four different universities, evaluated the cyclic inelastic strain behavior of rolled steel shapes, the performance characteristics of rotary and gag-straightened rolled column sections, assessed beam-to-column joint assemblies and updated the standard shape material properties database for improved design and reliability. This paper gives an overview of new seismic connection details for moment frames and summarizes the results of the k-area research effort. [Copyright &y& Elsevier]