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In this paper, a three-dimensional (3-D) distributed cooperative guidance scheme is presented for multiple missiles to attack a single maneuvering target at pre-specified impact angles. A finite time observer is firstly proposed to provide accurate estimates of full states and disturbances; this is particularly crucial since some system states are not available as they are dependent on the unknown acceleration of the target. Then the guidance law is designed, which consists of two parts: the individual part and cooperative part. In the individual part, each missile is designed separately such that it will fly along the desired line of sight (LOS) after a given time which ensures hit-to-kill attack for the maneuvering target at the desired impact angles. In the cooperative part, the guidance law is designed for each missile using only information from adjacent missiles, to make all missiles hit the target at the same time. Hence it is ensured that all missiles can hit the target simultaneously, as well as at the desired directions (impact angles), then successfully achieving salvo attack. Finally, simulations are performed to verify the effectiveness of the proposed scheme. [ABSTRACT FROM AUTHOR]

Abstract: The truffle species Tuber anniae was originally described from the U.S. Pacific Northwest and is purported to be uncommon. Here, we report for the first time on the fruiting of closely related taxa in Baltic Rim countries. These truffles were found in a forest dominated by Scots pine in eastern Finland. Mycorrhizal analyses confirmed its symbiosis with Pinus sylvestris. Morphological observations of ascomata and mycorrhizae, and phylogenetic analyses confirmed that these white truffles belong within the group of Tuber puberulum (i.e., Puberulum clade). Further, they group in Clades II and III of the T. anniae species-complex. With the inclusion of sequences from GenBank we are able to demonstrate that the previously unnamed environmental clade (Clade II) has been found as ectomycorrhiza in symbiosis with pine, birch, oak, aspen and even orchids in Europe. Thus, the T. anniae species-complex as a whole (and two of the three clades within) exhibit considerable geographic disjuncts: Northwestern North America and the Baltic Rim of Europe. Clade II, which was collected in agricultural soils in Finland and along roadsides in Alaska, may also be adapted for colonization into new habitats. This may help to explain its presence in New Zealand (where Tuber is not native), which most likely resulted from human-mediated dispersal of these fungi through forestry or the nursery trade. Based on our results, we hypothesize that management practices such as organic and lime amendments, along with aeration, are beneficial to the fruiting of T. anniae. Further research is needed to determine the edibility of these species and whether commercial markets can be developed. [Copyright &y& Elsevier]

Plant endophytes are microorganisms that live in healthy plant tissues in part or all of their life history without causing obvious symptoms of infection in the host plants. Endophytes, a new type of microbial resource that can produce a variety of biological constituents, have great values for research and broad prospects for development. This article reviewed the research and development progress of endophytic fungi with cytotoxic activity between 2014 and 2017, including endophytic fungi sources, microbial taxonomy, compound classification and cytotoxic activity. The results showed that the 109 strains of endophytic fungi belong to 3 phyla, 7 classes and 50 genera. The secondary metabolites mainly contained alkaloids, terpenes, steroids, polyketides, quinones, isocoumarins, esters etc. The results of this study provide references for the development of new antitumor drugs and endophytes resources. [ABSTRACT FROM AUTHOR]