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Mapanoioideae are one of two subfamilies of Cyperaceae and consist of 186 species. Molecular phylogenetic relationships in subfamily Cyperoideae have recently been studied well, whereas evolutionary relationships in Mapanioideae remain little known. Subfamily Mapanioideae include two tribes. This study focuses on Hypolytreae, which is represented by three genera in Africa (Hypolytrum, Mapania and Principina). In this paper, we present the first molecular phylogenetic study of African Hypolytreae using a Sanger sequencing approach. We aim to (1) test whether Hypolytrum, Mapania and Principina are reciprocally monophyletic; (2) investigate whether the morphologically based sections in Hypolytrum and Mapania represent monophyletic taxa; (3) resolve species delimitation where multiple accessions could be sequenced and (4) explore the relationships of species occurring in West Tropical Africa vs. Central Africa. Our phylogenetic analyses strongly support Mapania and Hypolytrum as separate genera, but Principina is nested in Hypolytrum. This result is consistent with morphological differences. Mapania spp. are obligate rainforest species, but our results show that species from West Tropical Africa and species from Central Africa do not form separate clades. Dispersal between these regions may have happened during interglacial periods when the rainforest was continuous.

Power analysis attacks pose a significant threat to the security of cryptographic devices as they can reveal a secret key. Performing cryptographic operations based on a randomly varying clock (RVC) is a practical countermeasure against such attacks. The countermeasure makes it difficult to align power traces, which is a prerequisite for power analysis attacks to succeed. This paper introduces a synchronous real-time sampling (SRTS) technique as an advanced hardware-implemented approach to collect traces for a power analysis attack that negates countermeasures involving practical RVCs. By recovering the RVC, the leakage signal corresponding to the recovered clock edge is synchronously sampled in real time. We propose an analog-based hardware system implemented with two circuit blocks for SRTS operations, namely, a clock recovery block and an analog signal-processing block. The target of the power analysis attack is an Advanced Encryption Standard (AES)-128 software-implemented smart card operated at 20 MHz, which is varied in the range of 30% by the RVC countermeasure. The traces captured by the SRTS show that the suboperations of the AES encryption are distinct in contrast to the indistinguishable waveforms captured at a fixed sample rate. The results of the power analysis attack demonstrate that the correct key is successfully extracted with a high correlation coefficient at the S-box output of the AES. The proposed SRTS method improves the relative distinguishing margin by 191.4% and reduces the required number of traces to 2.75% compared with the conventional correlation power analysis attack with a fixed sample clock.

Robotic arthroscopy is a potential alternative surgery method because the use of robotic arthroscope manipulators could ensure a constant quality of view that would enhance the workflow of the operator. To achieve this advancement, a workspace derivation for the movement of the arthroscope in the human joint is needed. There is a key requirement for workspace derivation of the arthroscope: the workspace should incorporate all the essential observation sites to ensure a suitable field of view during an arthroscopic surgery for various patients. The workspace could be delineated via workspace measurements on various patients or cadavers; however, this would be an arduous process. Herein, we propose a workspace derivation using morphological measurement data of various human shoulder joints for arthroscopic rotator cuff repair, which is a typical operation in arthroscopy. First, we present the geometrical modeling of the human shoulder joint using morphological parameters and standard portal placement methods. Second, the morphological measurement data of the human joint are substituted for the parameters to determine the workspace required for arthroscopic rotator cuff repair. As a result, we obtain the location of each portal and the workspace of the arthroscope via the portals that incorporate all the essential observation sites. We verify the derived workspace through several cadaveric tests. For all the experimental results, it was confirmed that the $95^{th}$ percentile of the range of motion was formed within the workspace obtained using the proposed method. The results verify that the proposed method is feasible for arthroscopy.

While the power conversion efficiencies (PCEs) of organic solar cells (OSCs) have been dramatically increased through the development of small molecular acceptors (SMAs), achieving eco-friendly solution processability of OSCs is a crucial prerequisite for their practical application. In this study, we develop three new, green solvent-processable SMAs (YSe–C3, YSe–C6, and YSe–C9) with different outer side-chains (n-propyl (C3), n-hexyl (C6), and n-nonyl (C9)), affording high-performance OSCs with non-halogenated solvent (o-xylene)-processed active layers. Also, the impact of both outer and inner side-chain engineering of these SMAs on the performance of eco-friendly fabricated OSCs is systematically investigated. The outer side-chain structure has a much more significant impact than the inner side-chain. For example, the PM6:YSe–C6 blend affords high-performance OSCs with a power conversion efficiency (PCE) of over 16%, whereas the PCEs of the YSe–C3- and YSe–C9-based OSCs are only 11–14%. The lower PCEs of PM6:YSe–C3 and C9 are mainly attributed to reduced electron mobility and increased charge recombination, resulting from aggregate-containing non-optimal blend morphologies. Interestingly, the well-optimized morphology of the YSe–C6-based blend also affords OSC devices with active layer thickness-independent PCEs, up to a thickness of >400 nm, demonstrating the great potential for large-area device manufacturing via an eco-friendly printing process. Thus, optimizing the outer side-chain structure of Y-series SMAs is essential for producing green solvent-processed high-performance OSCs.

The aggregation properties of conjugated polymers can play a crucial role in their thin film structures and performance of electronic devices. Control of these aggregated structures is particularly important in producing efficient all-polymer solar cells (all-PSCs), considering that strong demixing of the polymer donor and polymer acceptor typically occurs during film formation because of the low entropic contribution to the thermodynamics of the system. Here, three naphthalenediimide (NDI)-based polymer acceptors with different backbone chlorination patterns are developed to investigate the effect of the chlorination patterns on the aggregation tendencies of the polymer acceptors, which greatly influence their crystalline structures, electrical properties, and device performances of the resultant all-PSCs and organic field-effect transistors (OFETs). The counterparts of NDI units, dichlorinated bithiophene (Cl2T2), monochlorinated bithiophene (ClT2), and dichlorinated thienylene-vinylene-thienylene (Cl2TVT), are employed to synthesize a series of P(NDIOD-Cl2T2), P(NDIOD-ClT2), and P(NDIOD-Cl2TVT) polymers. The P(NDIOD-Cl2T2) polymer takes advantage of strong noncovalent bonding induced by its chlorine substituents, resulting in the formation of optimal face-on oriented crystalline structures which are suitable for efficient all-PSC devices. In comparison, the P(NDIOD-Cl2TVT) polymer forms bimodal crystalline structures in thin films to yield optimal performances in the resultant OFETs. When the three chlorinated polymers are applied to all-PSCs with the PBDTTTPD polymer donor, P(NDIOD-Cl2T2) achieves a maximum power conversion efficiency (PCE) of 7.22% with an appropriate blend morphology and high fill factor, outperforming P(NDIOD-ClT2) (PCE = 4.80%) and P(NDIOD-Cl2TVT) (PCE = 5.78%). Our observations highlight the effectiveness of the chlorination strategy for developing efficient polymer acceptors and demonstrate the important role of polymer aggregation in modulating the blend morphology and all-PSC performance.

For precision enhancement, many robotic systems for minimally invasive surgery (MIS) have been developed. However, a positioning arm that firmly fixes the initial position of surgical robot arm has not been researched in depth yet. Since a positioning arm is a device for positioning a surgical robots, it should be equipped with a robust locking mechanism against external force. Furthermore, as repositioning of the surgical robot occurs frequently before and during the operation, the positioning arm needs a mechanism to lock and unlock multi-degrees-of-freedom (MDoF) simultaneously to reduce the setup time. Therefore, we propose a novel MDoF locking mechanism applicable to a positioning arm for MIS. When the knob of the locking mechanism is rotated, the two joints are locked simultaneously by the movement of the friction pad and the locking block that is mounted inside the positioning arm. Considering the locking time and the locking torque, the design parameters of the locking mechanism were determined to be optimal. The proposed locking mechanism was implemented and verified on a positioning arm for MIS. The first experimental results showed that only the negligible clearance between the joints was generated during the locking and unlocking transition. These indicate that positioning of the surgical robot is precise when the proposed mechanism is applied. The second experimental results showed that the proposed locking mechanism has a higher performance than the conventional locking device, in terms of locking torque. These indicate that the proposed locking mechanism will enhance safety in a surgical environment.

Despite the recent breakthroughs of polymer solar cells (PSCs) exhibiting a power conversion efficiency of over 17%, toxic and hazardous organic solvents such as chloroform and chlorobenzene are still commonly used in their fabrication, which impedes the practical application of PSCs. Thus, the development of eco-friendly processing methods suitable for industrial-scale production is now considered an imperative research focus. This Review provides a roadmap for the design of efficient photoactive materials that are compatible with non-halogenated green solvents (e.g., xylenes, toluene, and tetrahydrofuran). We summarize the recent development of green processing solvents and the processing methods to match with the efficient photoactive materials used in non-fullerene solar cells. We further review progress in the use of more eco-friendly solvents (i.e., water or alcohol) for achieving truly sustainable and eco-friendly PSC fabrication. For example, the concept of water- or alcohol-dispersed nanoparticles made of conjugated materials is introduced. Also, recent important progress and strategies to develop water/alcohol-soluble photoactive materials that completely eliminate the use of conventional toxic solvents are discussed. Finally, we provide our perspectives on the challenges facing the current green processing methods and materials, such as large-area coating techniques and long-term stability. We believe this Review will inform the development of PSCs that are truly clean and renewable energy sources.

This paper presents a dynamic effect of clay types and content on low salinity water-flooding (LSF) based on coreflooding experiments. The EDL (electrical double layer) expansion, MIE (multicomponent ion exchange), local pH increase between clay minerals and brine are investigated to get a better understanding on the complexity of role of clay in LSF. The results of coreflooding experiments using unconsolidated core sample show that the incremental oil recovery of kaolinite is higher than that of illite at the same clay content. Kaolinite and illite have a positive effect on MIE, EDL expansion, and local pH increase. The incremental oil recovery was proportional to the local pH increase in both core samples. Especially, more MIE and EDL expansion occur in kaolinite core samples. Therefore, the wettability is further changed to the water-wet condition in kaolinite sample. The results of correlation coefficient analysis show the kaolinite content has a strong correlation with MIE, EDL expansion, local pH increase, and oil recovery. On the other hand, the correlations between oil recovery and chemical reactions in illite samples are relatively low compared to the kaolinite samples excepting local pH increase. Therefore, the sandstone reservoir containing kaolinite is more suitable for the LSF.

Eco-friendly polymer solar cells (eco-PSCs) based on aqueous-soluble conjugated materials have recently received great research attention. In this work, we report the development of an aqueous-processable C70-based fullerene derivative (PC71BO15) for eco-PSCs processed by water/ethanol co-solvents. The desirable aggregation behavior and enhanced light absorption ability of PC71BO15 have enabled the fabrication of PPDT2FBT-A:PC71BO15-based eco-PSCs with power conversion efficiencies (PCEs) of up to 2.51%, which is the highest value reported to date for aqueous-processed PSCs. These PPDT2FBT-A:PC71BO15 eco-PSCs exhibit significantly higher PCEs than those of the reference PPDT2FBT-A:PC61BO15 devices over all device-processable water/ethanol compositions. At the optimal water/ethanol composition (v/v = 15 : 85), the PCE of the PPDT2FBT-A:PC71BO15 eco-PSCs is 73% higher than that of the PC61BO15-based counterparts, as a result of enhanced light absorption. Importantly, the PC71BO15-based eco-PSCs show much higher tolerance in their PCEs to the water/ethanol composition. For example, the PCEs of the PPDT2FBT-A : PC71BO15 eco-PSCs at a 30 : 70 water/ethanol ratio maintain 89% of the optimal performance at a 15 : 85 ratio, whereas the PC61BO15-based devices only maintain 45%. This large difference in terms of water-tolerant behavior is mainly related to the different aggregation behaviors between PC71BO15 and PC61BO15 in blend films, which are carefully investigated using electrical, optical and morphological characterizations. This high water composition-tolerance affords an excellent reproducibility of the PC71BO15-based eco-PSCs with eco/human-friendly aqueous processing under ambient conditions.

Habenaria cruciformis (Orchidaceae), endemic to South Korea, is a perennial herb and its local population sizes are declined because of the destruction caused by human activity and the invasion of exotic species in their habitats. Here, we report the complete chloroplast (cp) genome sequence of H. cruciformis, which will provide valuable information for its biological conservation and future studies for the cp genome evolution of endemic plants on the Korean Peninsula. The cp genome of H. cruciformis is 155,708 bp in length, containing a large single-copy region of 85,131 bp and a small single-copy region of 17,659 bp which are separated by a pair of inverted repeats of 26,459 bp. The H. cruciformis cp genome encodes 131 genes, of which 113 are unique, including 79 protein-coding genes, 30 tRNA genes, and 4 rRNA genes. The overall GC content is 36.6%, which is consistent with the Habenaria species previously reported. Our phylogenomic analyses identified the sister relationship between H. cruciformis and H. linearfolia in the genus.

For safety enhancement reasons, passive gravity compensation is widely applied in robotic systems used in minimally invasive surgery (MIS). MIS robotic systems have a remote center of motion (RCM) in which a surgical instrument conducts a fulcrum motion around a point of invasion. RCM mechanisms include three-degrees-of-freedom (3-DoF): roll, pitch, and translation. Existing studies to date have focused on multi-degrees-of-freedom gravity compensation mechanisms by installing springs and wires in a robot. However, a gravity compensation mechanism with 3-DoF that simultaneously uses all three-directional movements (roll, pitch, and translation) has not yet been researched. Here, we propose a novel gravity compensation mechanism applicable to a 3-DoF MIS robotic arm with an RCM mechanism. When a translational motion is exerted, the proposed gravity compensator can adjust the roll-pitch-directional compensating torque by utilizing a reduction gear box and wire cable. To verify the 3-DoF gravity compensation, a gravity-compensated robotic arm for MIS and customized torque sensors was manufactured and calibrated. The results showed that the proposed static balancing mechanism can compensate for the gravitational torque with respect to roll, pitch, and translation. The total torque error along the roll and pitch axis was less than 0.38 N·m. In particular, the torque variation due to the translational motion was less than 0.13 N·m.

Intraspecific genetic variation provides the information on the distributional pattern of plant species by inducing local adaptation, range shifts, and range reduction. Here, genetic variation of amplified fragment length polymorphism (AFLP) and three chloroplast DNA (cpDNA) regions (atpI-atpH, trnD-psbM, and trnT-L) is investigated in 37 populations of Camellia japonica to assess the genetic diversity and population structure. We also infer the phylogeographical history of C. japonica distributed in South Korea, Japan (Kyushu and Okinawa), and Taiwan of East Asia. The AFLP results reveal high levels of genetic diversity in C. japonica across East Asia. At the regional level, the Kyushu populations display the highest level of genetic variation, whereas the mainland populations of South Korea exhibit the lowest level of variation. Our results show trends of loss of genetic diversity along with latitude. On the basis of 154 polymorphic sites of the combined three cpDNA regions, 11 haplotypes (A-K) were identified across the East Asian C. japonica populations. Haplotypes A-C are dominant and widespread in South Korea and Japan, while Haplotypes G, I, and J in Taiwan. In addition, five haplotypes (A, B, D-F) are exclusively occur in South Korea/Japan and five (G-K) are in Taiwan. Our molecular dating analysis estimates the age of initial diversification of C. japonica haplotypes in the late Tertiary. The phylogeographic patterns of C. japonica coupled with molecular dating suggest vicariance as key mechanism for initial diversification between South Korea/Japan and Taiwan. In contrast, the haplotypes of Japan are shared with those of South Korea indicating that they had insufficient time to form population structures at the regional level.

Endemic plants are important for understanding phylogenetic relationships, biogeographical history, and genetic variation because of their restricted distribution and their role in conserving biodiversity. Here, we investigated the phylogenetic relationships of the Korean endemic

Allioideae includes economically important bulb crops such as garlic, onion, leeks, and some ornamental plants in Amaryllidaceae. Here, we reported the complete chloroplast genome (cpDNA) sequences of 17 species of Allioideae, five of Amaryllidoideae, and one of Agapanthoideae. These cpDNA sequences represent 80 protein-coding, 30 tRNA, and four rRNA genes, and range from 151,808 to 159,998 bp in length. Loss and pseudogenization of multiple genes (i.e., rps2, infA, and rpl22) appear to have occurred multiple times during the evolution of Alloideae. Additionally, eight mutation hotspots, including rps15-ycf1, rps16-trnQ-UUG, petG-trnW-CCA, psbA upstream, rpl32-trnL-UAG, ycf1, rpl22, matK, and ndhF, were identified in the studied Allium species. Additionally, we present the first phylogenomic analysis among the four tribes of Allioideae based on 74 cpDNA coding regions of 21 species of Allioideae, five species of Amaryllidoideae, one species of Agapanthoideae, and five species representing selected members of Asparagales. Our molecular phylogenomic results strongly support the monophyly of Allioideae, which is sister to Amaryllioideae. Within Allioideae, Tulbaghieae was sister to Gilliesieae-Leucocoryneae whereas Allieae was sister to the clade of Tulbaghieae- Gilliesieae-Leucocoryneae. Molecular dating analyses revealed the crown age of Allioideae in the Eocene (40.1 mya) followed by differentiation of Allieae in the early Miocene (21.3 mya). The split of Gilliesieae from Leucocoryneae was estimated at 16.5 mya. Biogeographic reconstruction suggests an African origin for Allioideae and subsequent spread to Eurasia during the middle Eocene. Cool and arid conditions during the late Eocene led to isolation between African and Eurasian species. African Allioideae may have diverged to South American taxa in the late Oligocene. Rather than vicariance, long-distance dispersal is the most likely explanation for intercontinental distribution of African and South American Allioideae species.

Background Carduus, commonly known as plumeless thistles, is a genus in the Asteraceae family that exhibits both medicinal value and invasive tendencies. However, the genomic data of Carduus (i.e., complete chloroplast genomes) have not been sequenced. Methods We sequenced and assembled the chloroplast genome (cpDNA) sequences of three Carduus species using the Illumina Miseq sequencing system and Geneious Prime. Phylogenetic relationships between Carduus and related taxa were reconstructed using Maximum Likelihood and Bayesian Inference analyses. In addition, we used a single nucleotide polymorphism (SNP) in the protein coding region of the matK gene to develop molecular markers to distinguish C. crispus from C. acanthoides and C. tenuiflorus. Results The cpDNA sequences of C. crispus, C. acanthoides, and C. tenuiflorus ranged from 152,342 bp to 152,617 bp in length. Comparative genomic analysis revealed high conservation in terms of gene content (including 80 protein-coding, 30 tRNA, and four rRNA genes) and gene order within the three focal species and members of subfamily Carduoideae. Despite their high similarity, the three species differed with respect to the number and content of repeats in the chloroplast genome. Additionally, eight hotspot regions, including psbI-trnS_GCU, trnE_UUC-rpoB, trnR_UCU-trnG_UCC, psbC-trnS_UGA, trnT_UGU-trnL_UAA, psbT-psbN, petD-rpoA, and rpl16-rps3, were identified in the study species. Phylogenetic analyses inferred from 78 protein-coding and non-coding regions indicated that Carduus is polyphyletic, suggesting the need for additional studies to reconstruct relationships between thistles and related taxa. Based on a SNP in matK, we successfully developed a molecular marker and protocol for distinguishing C. crispus from the other two focal species. Our study provides preliminary chloroplast genome data for further studies on plastid genome evolution, phylogeny, and development of species-level markers in Carduus.

We present a new series of fullerene derivatives that exhibit solubility in ethanol/water solvent mixtures and implement these materials to fabricate polymer solar cells (PSCs) using environmentally benign solvents. In order to simultaneously optimize the processability of the fullerenes in ethanol/water solvent mixtures and device performance, different fullerene mono-adducts were designed by introducing oligoethylene glycol side chains with different lengths and number of branches. As a result, we achieved power conversion efficiencies up to 1.4% for PSCs processed from benign ethanol/water mixtures in air. Significantly, the new alcohol/water-soluble fullerene derivatives displayed electron mobilities up to 1.30 × 10–4 cm2 V–1 s–1, 150 times higher than those of a previously reported alcohol-soluble fullerene bis-adduct, owing to efficient packing of the fullerenes. Femtosecond transient absorption spectroscopy revealed the acceptor side chain to markedly impact geminate and/or nongeminate charge recom...

Premise of the study Understanding the underlying mechanisms for the evolution of intercontinental disjunct patterns has long fascinated botanists. We present a molecular phylogenetic reconstruction of Maianthemum s.l. (including Smilacina) with a focus on Maianthemum s.s. species, which have a disjunct distribution between Eurasia and North America. Within this evolutionary framework, we clarify the systematic classification and biogeographical history of Maianthemum s.s. Method Data from two nuclear and five chloroplast DNA regions were analyzed using the programs PAUP*, RAxML, MrBayes, BEAST, and RASP. Key results Our molecular phylogeny supports Maianthemum s.s. as monophyletic. Maianthemum bifolium and M. canadense are grouped according to their taxonomic species, but the accessions of M. dilatatum are divided into two well-defined groups, i.e., one comprising western North American accessions, and the other composed of northeast Asian accessions. Molecular dating and biogeographic reconstructions suggest a northeast Asian origin for Maianthemum s.s. and that a complicated pattern of divergent evolution began approximately in the late Miocene. Intercontinental disjunctions of Maianthemum s.s. in the Northern Hemisphere appear to have occurred two times during the Pliocene. Conclusions Based on our results, two possible ways to treat Maianthemum s.s. species can be envisioned: (1) elevate Asian populations of M. dilatatum to specific rank; or (2) combine the three Maianthemum s.s. species into a broadly defined single species. We recommend treatment of Maianthemum s.s. as a single species. The biogeographic patterns of Maianthemum s.s. coupled with molecular dating suggest both vicariance and long-distance dispersal events as key mechanisms for diversification of the clade.

This study presents experimental results on the variation of relative permeability due to clay types and contents in low salinity water-flooding. To analyze the effect of clay types and contents on relative permeability, core-flooding using unconsolidated sand core samples was conducted. Relative permeability curves were measured from the experiments using the Johnson, Bossler, and Naumann (JBN) method. From the results, the moving range (S or -S wi ) of the relative permeability curve was proportional to the clay contents of kaolinite. The moving range for illite also showed a relative permeability curve proportional to the clay contents, but it was less than that for kaolinite. To extend the equation of the Honarpour end-point relative permeability curves in low salinity water-flooding, end-point relative permeability curves were matched with the experimental relative permeability curves by changing the Honarpour index N o and N w . Then, the difference of N o and N w between the conventional water-flooding and the low salinity water-flooding was correlated with the clay contents. Based on the results, extended functions of index N o and N w were proposed to describe the relative permeability curves applied to low salinity water-flooding. It is believed that end-point relative permeability curves can be determined by the proposed N o and N w instead of the conventional exponent index in low salinity water-flooding with reservoirs containing kaolinite.

Background Carduus, commonly known as plumeless thistles, is a genus in the Asteraceae family that exhibits both medicinal value and invasive tendencies. However, the genomic data of Carduus (i.e., complete chloroplast genomes) have not been sequenced. Methods We sequenced and assembled the chloroplast genome (cpDNA) sequences of three Carduus species using the Illumina Miseq sequencing system and Geneious Prime. Phylogenetic relationships between Carduus and related taxa were reconstructed using Maximum Likelihood and Bayesian Inference analyses. In addition, we used a single nucleotide polymorphism (SNP) in the protein coding region of the matK gene to develop molecular markers to distinguish C. crispus from C. acanthoides and C. tenuiflorus. Results The cpDNA sequences of C. crispus, C. acanthoides, and C. tenuiflorus ranged from 152,342 bp to 152,617 bp in length. Comparative genomic analysis revealed high conservation in terms of gene content (including 80 protein-coding, 30 tRNA, and four rRNA genes) and gene order within the three focal species and members of subfamily Carduoideae. Despite their high similarity, the three species differed with respect to the number and content of repeats in the chloroplast genome. Additionally, eight hotspot regions, including psbI-trnS_GCU, trnE_UUC-rpoB, trnR_UCU-trnG_UCC, psbC-trnS_UGA, trnT_UGU-trnL_UAA, psbT-psbN, petD-rpoA, and rpl16-rps3, were identified in the study species. Phylogenetic analyses inferred from 78 protein-coding and non-coding regions indicated that Carduus is polyphyletic, suggesting the need for additional studies to reconstruct relationships between thistles and related taxa. Based on a SNP in matK, we successfully developed a molecular marker and protocol for distinguishing C. crispus from the other two focal species. Our study provides preliminary chloroplast genome data for further studies on plastid genome evolution, phylogeny, and development of species-level markers in Carduus.

Recent advances in phylogenetics indicate that reticulate evolution has played an important role in the emergence of Isoetes species in the North Pacific region. However, the biogeographical origin of the North Pacific Isoetes species remains contentious. We present a fossilcalibrated phylogeny of species from the North Pacific region based on molecular data. Within this framework, we discuss their ancestral areas and biogeographical history. North Pacific Isoetes are divided into two clades: clade I, consisting of East Asian, Papua New Guinean, and Australian species, and clade II, consisting of West Beringian and western North American species. Within clade I, Australian Isoetes species were an early divergent group, and Papua New Guinea’s species form a sister clade to the East Asian species. Biogeographical reconstructions suggest an Australasian origin for the East Asian species that arose through long-distance dispersal during the late Oligocene. Within clade II, I. asiatica from West Beringia forms a clade with I. echinospora and I. muricata from Alaska. Western North America was the area of origin for the dispersal of Isoetes species to West Beringia via the Bering land bridge during the late Miocene. Our study identifies the biogeographic origin of the North Pacific Isoetes and suggests long-distance dispersal as the most likely explanation for their intercontinental distribution.

The hottest news and achievements of space science and research in recent years may be NASA Curiosity rover’s exploration (2013) of Mars, China Chang’e 3’s exploration (2013) of Moon, ESA Rosetta’s exploration (2014) of Comet 67P/Churyumov-Gerasimenko, and NASA New Horizons’ exploration (2015) of Pluto, which are very astonishing achievement since such a deep space journey was possible with current technology. In contrast the wonderful cruise and navigation technologies evolution of explorer in deep space, there are no remarkable changes in deep space data communication, it is still in conservative area, of which much changes are reluctantly accepted so far. But there are some movements of deep space exploration in order to allow ground brilliant technologies to deep space. One of those experiments is internet, whose main topic of this paper. In this paper, we will present the analysis of effectiveness of solar system internet to deep space exploration.

Intercontinental floristic disjunction between East Asia and North America in the Northern Hemisphere has received much attention during the past decades, but few studies have focused on the family level. Melanthiaceae, containing 196 species and 17 genera circumscribed in five tribes, is disjunctly distributed in Eurasia and North America. It is one of the foremost models for studying the evolution of biogeographic patterns in this region. Here, we present a fossil-calibrated, molecular phylogeny of Melanthiaceae based on two chloroplast DNA datasets: one dataset includes extensive sampling (94 species representing all 17 genera of Melanthiaceae) of four chloroplast DNA regions (atpB, rbcL, matK, and ndhF) and the other includes six species representing all tribes of the family for 78 coding genes of the chloroplast genome. Within this framework, we infer the historical biogeography of Melanthiaceae. Both datasets produce well-resolved phylogenies of Melanthiaceae showing the monophyly of the family and the relationships among the five tribes. Melanthieae is found to be sister to the rest of the tribes of the family and the remaining taxa are divided into two major clades consisting of the Chionographideae + Heloniadeae clade and the Parideae + Xerophylleae clade. The molecular dating and the ancestral area analyses suggest that Melanthiaceae most likely originated in North America with its crown group dated at 92.1 mya in the late Cretaceous. The favored ancestral areas at the crown lineages of tribes are also in North America. In the family, seven independent migrations into East Asia from North America are inferred to have occurred in the Oligocene and the Miocene-Pliocene via historical paleo-land bridge connections. Cooling trends during the Oligocene resulted in the present East Asia-North America disjunct distribution, while the warm period during the middle Miocene and habitat heterogeneity stimulated diversification in East Asia. Our study provides the phylogenetic and biogeographical history of the Melanthiaceae and adds an example of “out of North America” migration in the biogeographic history of the Northern Hemisphere.

Background Hybridization is an important evolutionary process that results in increased plant diversity. Flowering Prunus includes popular cherry species that are appreciated worldwide for their flowers. The ornamental characteristics were acquired both naturally and through artificially hybridizing species with heterozygous genomes. Therefore, the genome of hybrid flowering Prunus presents important challenges both in plant genomics and evolutionary biology. Results We use long reads to sequence and analyze the highly heterozygous genome of wild Prunus yedoensis. The genome assembly covers > 93% of the gene space; annotation identified 41,294 protein-coding genes. Comparative analysis of the genome with 16 accessions of six related taxa shows that 41% of the genes were assigned into the maternal or paternal state. This indicates that wild P. yedoensis is an F1 hybrid originating from a cross between maternal P. pendula f. ascendens and paternal P. jamasakura, and it can be clearly distinguished from its confusing taxon, Yoshino cherry. A focused analysis of the S-locus haplotypes of closely related taxa distributed in a sympatric natural habitat suggests that reduced restriction of inter-specific hybridization due to strong gametophytic self-incompatibility is likely to promote complex hybridization of wild Prunus species and the development of a hybrid swarm. Conclusions We report the draft genome assembly of a natural hybrid Prunus species using long-read sequencing and sequence phasing. Based on a comprehensive comparative genome analysis with related taxa, it appears that cross-species hybridization in sympatric habitats is an ongoing process that facilitates the diversification of flowering Prunus. Electronic supplementary material The online version of this article (10.1186/s13059-018-1497-y) contains supplementary material, which is available to authorized users.

Figure S1. K-mer plots of wild P. yedoensis (Pyn) and â Yoshino cherryâ (Pxy) accessions. Figure S2. A workflow of genome assembly and annotation. Figure S3. Chromosomal comparison of the gene-phased genome assembly of wild P. yedoensis (Pyn) with the P. avium (Pa) and P. mume (Pm) genomes. Figure S4. A maximum likelihood tree of S-locus genes showing the phylogenetic relationship among the S haplotypes. (DOCX 670 kb)

The diploid aquatic genus Sparganium (Typhaceae) comprises ca. 14 species mainly in cool temperate regions of the world. Among these, S. emersum comprises two infraspecific taxa, subspecies acaule from eastern North America and subspecies emersum from Eurasia and western North America (and occasionally from eastern North America as well). However, there has been some discussion regarding the monophyly of S. emersum sensu lato. We tested the hypothesis of a polyphyletic S. emersum sensu lato in a phylogenetic framework. Sequence data from six plastid DNA regions and nuclear phyC were analyzed using maximum parsimony, maximum likelihood, and Bayesian inference. We obtained a moderately resolved phylogeny with the plastid DNA data set, while phylogenetically less-informative phyC was useful to distinguish morphological species and discern hybrid and non-hybrid specimens. Sparganium emersum sensu lato was resolved as polyphyletic, clustering with S. angustifolium and S. glomeratum, respectively. Sparganium acaule is resurrected to be a sister to S. glomeratum, for which synapomorphic and distinguishing morphological characters are provided. Three cases of hybridization were detected.