Fern genomes elucidate land plant evolution and cyanobacterial symbioses

Li F-W, Brouwer P, Carretero-Paulet L, et al. Fern genomes elucidate land plant evolution and cyanobacterial symbioses. NATURE PLANTS. 2018;4(7):460-472

Wearables in medicine

Wearables as medical technologies are becoming an integral part of personal analytics, measuring physical status, recording physiological parameters, or informing schedule for medication. These continuously evolving technology platforms do not only promise to help people pursue a healthier life style, but also provide continuous medical data for actively tracking metabolic status, diagnosis, and treatment. Advances in the miniaturization of flexible electronics, electrochemical biosensors, microfluidics, and artificial intelligence algorithms have led to wearable devices that can generate real-time medical data within the Internet of things. These flexible devices can be configured to make conformal contact with epidermal, ocular, intracochlear, and dental interfaces to collect biochemical or electrophysiological signals. This article discusses consumer trends in wearable electronics, commercial and emerging devices, and fabrication methods. It also reviews real-time monitoring of vital signs using biosensors, stimuli-responsive materials for drug delivery, and closed-loop theranostic systems. It covers future challenges in augmented, virtual, and mixed reality, communication modes, energy management, displays, conformity, and data safety. The development of patient-oriented wearable technologies and their incorporation in randomized clinical trials will facilitate the design of safe and effective approaches

Spore morphology and its systematic implication in Pteris (Pteridaceae).

Pteris (Pteridaceae) spores are usually trilete and can be distinguished by the perine ornamentation. The systematic value of spore morphology in Pteris is unclear, especially based on the renewed infrageneric classification of Pteris. In the present study, we used scanning electron microscopy (SEM) to understand spore characters in 57 Pteris species, one Onychium species, and two Astrolepis species; 40 species are reported here for the first time. The observed spore characters combined with published spore data, totaling 100 species from 16 sections of Pteris, were mapped onto a reconstructed phylogenetic tree. Seven characters (five proposed in previous studies), including an equatorial flange, laesural ridges, proximal ridges, distal ridges, tubercula on distal faces, coarse reticula on distal faces, and a row of extervermiculi between the distal face and equatorial flange, were analyzed to investigate spore morphology evolution in Pteris. However, the results showed no synapomorphies with other genera in Pteridaceae. Most of the characters were found to have arisen independently several times in different lineages or were even frequently reversed. Equatorial flanges and tubercula on distal faces are plesiomorphies and present in most Pteris species. Overall, the application of spore morphology in section circumscription is limited. Thus, we suggest combining spore morphology with leaf characters for Pteris infrageneric classification

Biological studies of Pteris fauriei complex (Pteridaceae)

[[abstract]]Pteris fauriei Hieron. is a very common, evergreen fern in Japan, China, the Ryukyu Islands, Taiwan and Vietnam. In Taiwan, two taxa, P. fauriei var. fauriei and P. fauriei var. minor Hieron. have been documented. These two varieties can be distinguished based on spore size, the number of spores in each sporangium, the number of sperm in each antheridium, antheridium size, reproductive behavior, and the morphology of juvenile sporophyte fronds. Using spore size, the type specimens of P. fauriei var. fauriei and P. fauriei var. minor, collected by U. Faurie in 1904 and published by Hieronymus in 1914, are able to be confirmed as triploid and diploid, respectively. Based on spore sizes and the number of spore per sporangium, the distribution and habitats of the two cytotypes in Taiwan are characterized from both living plants and herbarium specimens. Diploid plants distribute widely in Taiwan and nearby islands, but do not occur in central Taiwan or in the Matsu islands. In contrast, triploid plants are not found in southern Taiwan or on islands west of central Taiwan. In general, triploids grow at higher elevation and cooler habitat than the diploids. Both varieties have the same atpB-rbcL non-coding spacer sequence. No genetic differentiation between these two varieties in terms of this DNA sequence. ISSR molecular data shows that most genetic variations occur among populations and few within populations. Despite the nature of obligate apomictic of P. fauriei var. fauriei is detected, however, there is relative higher genetic variation in this variety than that in the diploid variety. Recurrent and independent origins are considered the major source of genetic variation of the apomictic triploid P. fauriei var. fauriei. This study documents that triploid Pteris fauriei var. fauriei and diploid P. fauriei var. minor have differentiated various cryptic characteristics, significant separation of reproductive modes, and the preference of their distribution and habitats. However, the genotypes of the P. fauriei var. fauriei and var. minor do not distinctly separate from each other based on the genetic similarity derived from ISSR DNA markers.

Validation of the Name Adiantum meishanianum (Pteridaceae), a Species Endemic to Taiwan

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Morphology of the Gametophytes and Young Sporophytes of Cyatheaceae Native to Taiwan(1)

Seven species of Cyatheaceae are native to Taiwan. Sphaeropteris lepifera, Alsophila denticulata, A. metteniana, and A. podophylla produced 64 spores per sporangium, whereas A. loheri, A. spinulosa, and A. fenicis produced 16 spores per sporangium. Spore germination was Cyathea-type, except in A. denticulata and A. metteniana. In these two species, the rhizoid formation was delayed. Gametophytes of all seven species usually underwent Drynaria-type development, but a few gametophytes of all seven species exhibited Adiantum-type development. Multicellular, scale-like hairs on the dorsal and ventral surfaces of the midrib cushion increased in size and changed shape with age. These scale-like hairs distinguish Cyatheaceae gametophytes from the gametophytes of other fern families. The first three or four fronds of young sporophytes lacked midribs. Uniseriate to multiseriate and club-shaped pluricellular hairs were intermingled on the fronds of juvenile sporophytes of all six species of Alsophila. The lacking of club-shaped pluricellular hairs on Juvenile sporophytes of S. lepifera supports the taxonomic separation of Sphaeropteris from Alsophila. The presence of 16- and 64-spored sporangia suggests two evolutionary events within Alsophila

Affinities of the fern genus Ptisana (Marattiaceae) in the Solomon Islands, with descriptions of two new species

In the process of undertaking a comprehensive review of the pteridophytes of the Solomon Islands, multiple unidentified specimens of the fern genus Ptisana Murdock (Marattiaceae) were collected. Morphological and molecular phylogenetic analyses as well as field observations were required to identify the Solomon Islands taxa. Four species and one variety are recognized from the Solomon Islands: Ptisana ambulans Murdock & C.W. Chen, sp. nov., Ptisana decipiens Murdock & C.W. Chen, sp. nov., Ptisana decipiens var. delicata Murdock & C.W. Chen, var. nov., Ptisana papuana (Alderw.) Murdock & C.W. Chen, comb. nov., and Ptisana smithii (Mett. ex Kuhn) Murdock. The complexities in the identification of Solomon Islands collections show the limits of morphology in the genus and illuminate a path forward for untangling the Ptisana taxonomy on a broader scale

Pteris latipinna sp. nov. (Pteridaceae), a new species segregated from Pteris fauriei

Pteris fauriei is widely distributed in Eastern Asia and has high morphological variation. Some morphologically similar plants related to this species are difficult to distinguish. We showed that the new Pteris species from Taiwan, previously identified as P. fauriei, can be morphologically distinguished by its wide pinnae, larger terminal pinnae than the lateral pinnae in sterile fronds, and triangular basal segments of the lateral pinnae. It was confirmed that this species is phylogenetically separated from the other East Asian Pteris species, except for a morphologically distinct species P. arisanensis, by means of chloroplast genes, rbcL and matK. The new species is named as Pteris latipinna sp. nov., referring to its wide pinnae. Here, we provide a key to facilitate the identification of the morphologically similar Pteris species in Asia. The morphological descriptions, images, ecology, and distribution are also presented