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In order to find a natural alternative to the synthetic fungicides currently used against the devastating rice blast fungus, Magnaporthe grisea, this study explored the antifungal potential of citral and its mechanism of action. It was found that citral not only inhibited hyphal growth of M. grisea, but also caused a series of marked hyphal morphological and structural alterations. Specifically, citral was tested for antifungal activity against M. grisea in vitro and was found to significantly inhibit colony development and mycelial growth with IC50 and IC90 values of 40.71 and 203.75 μg/mL, respectively. Furthermore, citral reduced spore germination and germ tube length in a concentration-dependent manner. Following exposure to citral, the hyphal cell surface became wrinkled with folds and cell breakage that were observed under scanning electron microscopy (SEM). There was damage to hyphal cell walls and membrane structures, loss of villous-like material outside of the cell wall, thinning of the cell wall, and discontinuities formed in the cell membrane following treatment based on transmission electron microscopy (TEM). This increase in chitinase activity both supports the morphological changes seen in the hyphae, and also suggests a mechanism of action. In conclusion, citral has strong antifungal properties, and treatment with this compound is capable of causing significant damage to the hyphal cell walls of M. grisea. [ABSTRACT FROM AUTHOR]

Five Llandovery orthide brachiopod associations, through cluster analysis, are delineated on Anticosti Island. The Levenea–Dicoelosia Association (A), occurring in the Goéland and Richardson members of the lower Jupiter Formation, represents a deep-water setting around or below the maximum storm wave base. The Flabellitesia–Dalejina Association (B), appearing in the Cybèle, Ferrum, and Pavillon members of the upper Jupiter Formation, indicates water depth in between the maximum and normal storm wave bases. The Isorthis (Ovalella) Association (C1), present in the Fox Point Member of Becscie Formation, corresponds to the shallower water setting around the normal storm wave base. The Mendacella bleikeriensis Association (C2), occurring in the Innommée, Sandtop, and Macgilvray members of Gun River Formation, characterizes the water depth slightly below the normal storm wave base. The Mendacella udauberis Association (D), appearing in the Merrimack Formation, signifies a water depth around the maximum storm wave base. The water depth indication of these associations may bear potential as future reference for other regions, but attention should be paid to the species level as some congeneric species can belong to different associations of different depth. The cluster analysis on orthide collections based on binary data demonstrates that statistical methods, Jaccard coefficient and Ward’s method of clustering, are practical and effective to delineate large brachiopod collections on Anticosti Island. [ABSTRACT FROM AUTHOR]

Discovery of a single specimen of brachyuran decapod from the Campanian Millwood Member in southern Manitoba, Canada, permits description of a new genus and species, Cretacocarcinus smithi. Comparison of sternal architecture and general carapace morphology with potentially related taxa documents that the new genus, along with Camarocarcinus Holland and Cvancara, form a new family, Camarocarcinidae, tentatively assigned to the Raninoidea. The Camarocarcinidae are interpreted to have originated in the upper Midcontinental Seaway in the Late Cretaceous, survived the K–T extinction event(s), and dispersed into southern North Dakota, USA; Greenland; and Denmark in the Paleocene. [ABSTRACT FROM AUTHOR]

The upper Lower to Middle Devonian Bird Fiord Formation (late Emsian to late Eifelian) is a carbonate–siliciclastic succession, up to 900 m thick, that contains a diverse brachiopod-dominated fauna. Twenty-two species belonging to 21 genera have been recognized from the collection of more than 45 000 specimens, among which the atrypids form 52% of the biota, spiriferids ~13%, orthids ~8%, productids ~3%, rhynchonellids ~2%, terebratulids ~1%, and the strophomenids, pentamerids, and athyridids each <1%. Spinatrypina, Schizophoria, Elythyna, Desqumatia (Independentrypa), Cupularostrum, and Atrypa that collectively form more than 80% of the brachiopod biota. The following species are described here: Schizophoria (Schizophoria) sulcata, Ivdelinia grinnellensis, Cupularostrum repetitor, Hypothyridina cf. bifurcata, Atrypa sp., Emanuella bisinuata, Elythyna sverdrupi, Perryspirifer scheii, Costacranaena marlenae. Despite its endemic character, the brachiopod fauna from the Bird Fiord Formation of Arctic Canada can be assigned to the Old World Realm. Its strong affinity to Europe and western Canada supports the notion that, during the Devonian, faunal exchanges between Europe and North America took place via Arctic Canada. [ABSTRACT FROM AUTHOR]

The late Early Devonian to Middle Devonian Bird Fiord Formation, which is up to 900 m thick, is exposed along an extensive outcrop belt from stretches from Ellesmere Island to Bathurst Island in Arctic Canada. This formation, which encompasses sediments that accumulated in sabkha, deltaic, and shelf settings, is divided into six members. The Blubber Point, Baad Fiord, Norwegian Bay, and Cardigan Strait members, which include sediments that formed on an open marine shelf, are characterized by a diverse biota of brachiopods, mollusks, corals, trilobites, and sponges. The Cross Bay and Grise Fiord members, which encompass sediments that formed in a sabkha and delta plain settings, respectively, are generally devoid of fossils. A collection of 47,026 brachiopods, which came from 140 collections made at 34 locations throughout the outcrop belt of the Bird Fiord Formation, contains 22 species of brachiopods that belong to 21 genera. This biota includes six new species: Gypidula mega, Spinatrypa (Isospinatrypa) parva, Desquamatia (Independatrypa) fortis, Nucleospira stelcki, Warrenella grinnellensis, and Cranaena briceae. Four genera (Arcticastrophia Li and Jones, 2002, Borealistrophia Li and Jones, 2002, Grinnellathyris Li and Jones, 2002, and Costacranaena Johnson and Perry, 1976) and 16 species of brachiopods are endemic to the Arctic Canada. Conversely, the fauna also includes European elements such as Nucleospira lens (Schnur), Spinatrypa (Isospinatrypa), and Warrenella. These taxa may indicate that there was some communication between the Canadian Arctic and Europe during Middle Devonian. [ABSTRACT FROM AUTHOR]

Based on the nonlinear Schrödinger equation (NLSE) with damping, detuning, and driving terms describing the evolution of signals in a Kerr microresonator, we apply periodic nonlinear Fourier transform (NFT) to the study of signals during the generation of the Kerr optical frequency combs (OFCs). We find that the signals in different states, including the Turing pattern, the chaos, the single soliton state, and the multi-solitons state, can be distinguished according to different distributions of the eigenvalue spectrum. Specially, the eigenvalue spectrum of the single soliton pulse is composed of a pair of conjugate symmetric discrete eigenvalues and the quasi-continuous eigenvalue spectrum with eye-like structure. Moreover, we have successfully demonstrated that the number of discrete eigenvalue pairs in the eigenvalue spectrum corresponds to the number of solitons formed in a round-trip time inside the Kerr microresonator. This work shows that some characteristics of the time-domain signal can be well reflected in the nonlinear domain. [ABSTRACT FROM AUTHOR]