Correction: Effect of short-chain branching on interfacial polymer structure and dynamics under shear flow.

Correction for 'Effect of short-chain branching on interfacial polymer structure and dynamics under shear flow' by Sohdam Jeong et al., Soft Matter, 2017, 13, 8644-8650.

Effect of short-chain branching on interfacial polymer structure and dynamics under shear flow.

We present a detailed analysis on the effect of short-chain branches on the structure and dynamics of interfacial chains using atomistic nonequilibrium molecular dynamics simulations of confined polyethylene melts in a wide range of shear rates. The intrinsically fast random motions of the short branches constantly disturb the overall chain conformation, leading to a more compact and less deformed chain structure of the short-chain branched (SCB) polymer against the imposed flow field in comparison with the corresponding linear polymer. Moreover, such highly mobile short branches along the backbone of the SCB polymer lead to relatively weaker out-of-plane wagging dynamics of interfacial chains, with highly curvy backbone structures in the intermediate flow regime. In conjunction with the contribution of short branches (as opposed to that of the backbone) to the total interfacial friction between the chains and the wall, the SCB polymer shows a nearly constant behavior in the degree of slip (ds) with respect to shear rate in the weak-to-intermediate flow regimes. On the contrary, in the strong flow regime where irregular chain rotation and tumbling dynamics occur via intensive dynamical collisions between interfacial chains and the wall, an enhancement effect on the chain detachment from the wall, caused by short branches, leads to a steeper increase in ds for the SCB polymer than for the linear polymer. Remarkably, the SCB chains at the interface exhibit two distinct types of rolling mechanisms along the backbone, with a half-dumbbell mesoscopic structure at strong flow fields, in addition to the typical hairpin-like tumbling behavior displayed by the linear chains.

First report of the genus Semioscopis Hbner and four species of Gelechioidea (Lepidoptera) from Korea with redescriptions.

We report for the first time the presence of the genus Semioscopis Hbner, 1825 and four species of the superfamily Gelechioidea in Korea, namely Coleophora serinipennella Christoph, 1872 (Coleophoridae), Semioscopis japonicella Saito, 1989 (Depressariidae), Anarsia isogona Meyrick, 1913 (Gelechiidae) and Dichomeris syndyas Meyrick, 1926 (Gelechiidae). In addition, we provide redescription and diagnostic characteristics for each species, based on previous descriptions and additional morphological data acquired.

Can deliberately incomplete gene sample augmentation improve a phylogeny estimate for the advanced moths and butterflies (Hexapoda: Lepidoptera)?

This paper addresses the question of whether one can economically improve the robustness of a molecular phylogeny estimate by increasing gene sampling in only a subset of taxa, without having the analysis invalidated by artifacts arising from large blocks of missing data. Our case study stems from an ongoing effort to resolve poorly understood deeper relationships in the large clade Ditrysia ( > 150,000 species) of the insect order Lepidoptera (butterflies and moths). Seeking to remedy the overall weak support for deeper divergences in an initial study based on five nuclear genes (6.6 kb) in 123 exemplars, we nearly tripled the total gene sample (to 26 genes, 18.4 kb) but only in a third (41) of the taxa. The resulting partially augmented data matrix (45% intentionally missing data) consistently increased bootstrap support for groupings previously identified in the five-gene (nearly) complete matrix, while introducing no contradictory groupings of the kind that missing data have been predicted to produce. Our results add to growing evidence that data sets differing substantially in gene and taxon sampling can often be safely and profitably combined. The strongest overall support for nodes above the family level came from including all nucleotide changes, while partitioning sites into sets undergoing mostly nonsynonymous versus mostly synonymous change. In contrast, support for the deepest node for which any persuasive molecular evidence has yet emerged (78-85% bootstrap) was weak or nonexistent unless synonymous change was entirely excluded, a result plausibly attributed to compositional heterogeneity. This node (Gelechioidea + Apoditrysia), tentatively proposed by previous authors on the basis of four morphological synapomorphies, is the first major subset of ditrysian superfamilies to receive strong statistical support in any phylogenetic study. A "more-genes-only" data set (41 taxa×26 genes) also gave strong signal for a second deep grouping (Macrolepidoptera) that was obscured, but not strongly contradicted, in more taxon-rich analyses.

Two species of metallic Microlepidoptera, one new species of Adela Latreille, [1796] (Adeloidea, Adelidae) and one unrecorded species of Coleophora Hbner, 1822 (Gelechioidea, Coleophoridae), from Korea.

One new species of Adela Latreille, [1796], A. palella Koo Cho, sp. nov., belonging to Adelidae is described from Korea, and one species of Coleophora Hbner, 1822, C. fuscocuprella Herrich-Schffer, 1855, belonging to Coleophoridae is reported for the first time. Diagnostic characters and descriptions are provided along with close-up photographs of notable features of adults.

Four new species of Thubdora Park, 2018 and one new species of Torodora Meyrick, 1894 (Lepidoptera, Lecithoceridae, Torodorinae) from Tanzania.

Four new species of Thubdora Park, 2018 and one new species of Torodora Meyrick,1894 are described from Tanzania. The new species are Thubdora forficatalis Park Cho, sp. nov., T. mufindiensis Park Cho, sp. nov., T. ochrospilosa Park Cho, sp. nov., T. tanzaniana Park Cho, sp. nov., and Torodora melanonota Park Cho, sp. nov. Images of adults and genitalia of the new species are provided and a map for the type localities of the new species is given.

Bioinspired Gradient Conductivity and Stiffness for Ultrasensitive Electronic Skins.

Hierarchical and gradient structures in biological systems with special mechanical properties have inspired innovations in materials design for construction and mechanical applications. Analogous to the control of stress transfer in gradient mechanical structures, the control of electron transfer in gradient electrical structures should enable the development of high-performance electronics. This paper demonstrates a high performance electronic skin (e-skin) via the simultaneous control of tactile stress transfer to an active sensing area and the corresponding electrical current through the gradient structures. The flexible e-skin sensor has extraordinarily high piezoresistive sensitivity at low power and linearity over a broad pressure range based on the conductivity-gradient multilayer on the stiffness-gradient interlocked microdome geometry. While stiffness-gradient interlocked microdome structures allow the efficient transfer and localization of applied stress to the sensing area, the multilayered structure with gradient conductivity enables the efficient regulation of piezoresistance in response to applied pressure by gradual activation of current pathways from outer to inner layers, resulting in a pressure sensitivity of 3.8 × 105 kPa-1 with linear response over a wide range of up to 100 kPa. In addition, the sensor indicated a rapid response time of 0.016 ms, a low minimum detectable pressure level of 0.025 Pa, a low operating voltage (100 µV), and high durability during 8000 repetitive cycles of pressure application (80 kPa). The high performance of the e-skin sensor enables acoustic wave detection, differentiation of gas characterized by different densities, subtle tactile manipulation of objects, and real-time monitoring of pulse pressure waveform.

Structural and Dynamical Characteristics of Short-Chain Branched Ring Polymer Melts at Interface under Shear Flow.

We present a detailed analysis of the interfacial chain structure and dynamics of confined polymer melt systems under shear over a wide range of flow strengths using atomistic nonequilibrium molecular dynamics simulations, paying particular attention to the rheological influence of the closed-loop ring geometry and short-chain branching. We analyzed the interfacial slip, characteristic molecular mechanisms, and deformed chain conformations in response to the applied flow for linear, ring, short-chain branched (SCB) linear, and SCB ring polyethylene melts. The ring topology generally enlarges the interfacial chain dimension along the neutral direction, enhancing the dynamic friction of interfacial chains moving against the wall in the flow direction. This leads to a relatively smaller degree of slip (ds) for the ring-shaped polymers compared with their linear analogues. Furthermore, short-chain branching generally resulted in more compact and less deformed chain structures via the intrinsically fast random motions of the short branches. The short branches tend to be oriented more perpendicular (i.e., aligned in the neutral direction) than parallel to the backbone, which is mostly aligned in the flow direction, thereby enhancing the dynamic wall friction of the moving interfacial chains toward the flow direction. These features afford a relatively lower ds and less variation in ds in the weak-to-intermediate flow regimes. Accordingly, the interfacial SCB ring system displayed the lowest ds among the studied polymer systems throughout these regimes owing to the synergetic effects of ring geometry and short-chain branching. On the contrary, the structural disturbance exerted by the highly mobile short branches promotes the detachment of interfacial chains from the wall at strong flow fields, which results in steeper increasing behavior of the interfacial slip for the SCB polymers in the strong flow regime compared to the pure linear and ring polymers.

Fourteen new species of the genus Thubdora Park, 2018 (Lepidoptera: Gelechioidea: Lecithoceridae) from Uganda, and three new combinations in Ptilothyris Walsingham, 1897 from DR Congo.

Fourteen new species of the Afrotropical genus Thubdora Park, 2018 (Lecithoceridae: Torodorinae) are described from Uganda: Thubdora afropyralidis Park, sp. nov., T. fruticosa Park, sp. nov., T. kibalensis Park, sp. nov., T. klenodes Park, sp. nov., T. latidiscalis Park, sp. nov., T. mirinae Park, sp. nov., T. nemorosa Park, sp. nov., T. retusivalva Park, sp. nov., T. umbratilis Park, sp. nov., and T. wooriana Park, sp. nov. in the aciphalla species-group (10 species); and T. corystos Park, sp. nov., T. narusia Park, sp. nov., T. trigonoides Park, sp. nov., and T. villosiphalla Park, sp. nov. in the acutalis species-group (four species). Four species are reported for the first time from Uganda: T. ambliodes Park, 2018, T. bilobella Park, 2018, T. ealaensis Park De Prins, 2019, and T. ghesquierei Park De Prins, 2019; and the females of T. ealaensis and T. ghesquierei are newly described, and their genitalia are illustrated. In addition, three species of Ptilothyris Walsingham, 1897 previously recorded from DR Congo are transferred to Thubdora: T. brachysema (Meyrick, 1938), comb. nov., T. crocophracta (Meyrick, 1938), comb. nov., and T. nemophorella (Ghesquière, 1940), comb. nov. Lectotypes for T. brachysema and T. crocophracta are designated herein. Identifications of the new species and corresponding females were confirmed based on the comparison of COI barcode sequences. Adults and genitalia of all the new species and the three species transferred from Ptilothyris are illustrated.

Toward reconstructing the evolution of advanced moths and butterflies (Lepidoptera: Ditrysia): an initial molecular study.

BACKGROUND: In the mega-diverse insect order Lepidoptera (butterflies and moths; 165,000 described species), deeper relationships are little understood within the clade Ditrysia, to which 98% of the species belong. To begin addressing this problem, we tested the ability of five protein-coding nuclear genes (6.7 kb total), and character subsets therein, to resolve relationships among 123 species representing 27 (of 33) superfamilies and 55 (of 100) families of Ditrysia under maximum likelihood analysis. RESULTS: Our trees show broad concordance with previous morphological hypotheses of ditrysian phylogeny, although most relationships among superfamilies are weakly supported. There are also notable surprises, such as a consistently closer relationship of Pyraloidea than of butterflies to most Macrolepidoptera. Monophyly is significantly rejected by one or more character sets for the putative clades Macrolepidoptera as currently defined (P < 0.05) and Macrolepidoptera excluding Noctuoidea and Bombycoidea sensu lato (P < or = 0.005), and nearly so for the superfamily Drepanoidea as currently defined (P < 0.08). Superfamilies are typically recovered or nearly so, but usually without strong support. Relationships within superfamilies and families, however, are often robustly resolved. We provide some of the first strong molecular evidence on deeper splits within Pyraloidea, Tortricoidea, Geometroidea, Noctuoidea and others.Separate analyses of mostly synonymous versus non-synonymous character sets revealed notable differences (though not strong conflict), including a marked influence of compositional heterogeneity on apparent signal in the third codon position (nt3). As available model partitioning methods cannot correct for this variation, we assessed overall phylogeny resolution through separate examination of trees from each character set. Exploration of "tree space" with GARLI, using grid computing, showed that hundreds of searches are typically needed to find the best-feasible phylogeny estimate for these data. CONCLUSION: Our results (a) corroborate the broad outlines of the current working phylogenetic hypothesis for Ditrysia, (b) demonstrate that some prominent features of that hypothesis, including the position of the butterflies, need revision, and (c) resolve the majority of family and subfamily relationships within superfamilies as thus far sampled. Much further gene and taxon sampling will be needed, however, to strongly resolve individual deeper nodes.

Revision of the genus Ptilothyris Walsingham, 1897 (Lepidoptera: Gelechioidea: Lecithoceridae), with descriptions of eight new species from Africa.

Ptilothyris Walsingham, 1897, a poorly known Afrotropical genus of Lecithoceridae, is revised. Eight new species are described and illustrated: P. subcucullata Park, sp. nov., P. crassiella Park, sp. nov., P. drepanodes Park, sp. nov., P. enormisella Park, sp. nov., P. hylodes Park, sp. nov., P. leifaarviki Park, sp. nov., P. pilosa Park, sp. nov., and P. vokaensis Park, sp. nov. Each species is compared with type specimens of the related species deposited in various museums worldwide. COI barcode sequences of six species were successfully obtained and are provided. Of the 13 previously known African species of the genus, P. serangota ab. cyanea Ghesquière, 1940 is synonymized with P. serangota Meyrick, 1932, and the following three species are excluded from the genus: brachysema Meyrick, 1938, crocophracta Meyrick, 1938, and nemophorella Ghesquière, 1940. The latter three will be transferred to related genera in forthcoming studies. Adults and genitalia of all the known species including the new species are illustrated, and a key to the species is provided.

A Hierarchical Nanoparticle-in-Micropore Architecture for Enhanced Mechanosensitivity and Stretchability in Mechanochromic Electronic Skins.

Biological tissues are multiresponsive and functional, and similar properties might be possible in synthetic systems by merging responsive polymers with hierarchical soft architectures. For example, mechanochromic polymers have applications in force-responsive colorimetric sensors and soft robotics, but their integration into sensitive, multifunctional devices remains challenging. Herein, a hierarchical nanoparticle-in-micropore (NP-MP) architecture in porous mechanochromic polymers, which enhances the mechanosensitivity and stretchability of mechanochromic electronic skins (e-skins), is reported. The hierarchical NP-MP structure results in stress-concentration-induced mechanochemical activation of mechanophores, significantly improving the mechanochromic sensitivity to both tensile strain and normal force (critical tensile strain: 50% and normal force: 1 N). Furthermore, the porous mechanochromic composites exhibit a reversible mechanochromism under a strain of 250%. This architecture enables a dual-mode mechanochromic e-skin for detecting static/dynamic forces via mechanochromism and triboelectricity. The hierarchical NP-MP architecture provides a general platform to develop mechanochromic composites with high sensitivity and stretchability.

Skin-Inspired Hierarchical Polymer Architectures with Gradient Stiffness for Spacer-Free, Ultrathin, and Highly Sensitive Triboelectric Sensors.

The gradient stiffness between stiff epidermis and soft dermis with interlocked microridge structures in human skin induces effective stress transmission to underlying mechanoreceptors for enhanced tactile sensing. Inspired by skin structure and function, we fabricate hierarchical nanoporous and interlocked microridge structured polymers with gradient stiffness for spacer-free, ultrathin, and highly sensitive triboelectric sensors (TESs). The skin-inspired hierarchical polymers with gradient elastic modulus enhance the compressibility and contact areal differences due to effective transmission of the external stress from stiff to soft layers, resulting in highly sensitive TESs capable of detecting human vital signs and voice. In addition, the microridges in the interlocked polymers provide an effective variation of gap distance between interlocked layers without using the bulk spacer and thus facilitate the ultrathin and flexible design of TESs that could be worn on the body and detect a variety of pressing, bending, and twisting motions even in humid and underwater environments. Our TESs exhibit the highest power density (46.7 µW/cm2), pressure (0.55 V/kPa), and bending (∼0.1 V/°) sensitivities ever reported on flexible TESs. The proposed design of hierarchical polymer architectures for the flexible and wearable TESs can find numerous applications in next-generation wearable electronics.

Flexible Ferroelectric Sensors with Ultrahigh Pressure Sensitivity and Linear Response over Exceptionally Broad Pressure Range.

Flexible pressure sensors with a high sensitivity over a broad linear range can simplify wearable sensing systems without additional signal processing for the linear output, enabling device miniaturization and low power consumption. Here, we demonstrate a flexible ferroelectric sensor with ultrahigh pressure sensitivity and linear response over an exceptionally broad pressure range based on the material and structural design of ferroelectric composites with a multilayer interlocked microdome geometry. Due to the stress concentration between interlocked microdome arrays and increased contact area in the multilayer design, the flexible ferroelectric sensors could perceive static/dynamic pressure with high sensitivity (47.7 kPa-1, 1.3 Pa minimum detection). In addition, efficient stress distribution between stacked multilayers enables linear sensing over exceptionally broad pressure range (0.0013-353 kPa) with fast response time (20 ms) and high reliability over 5000 repetitive cycles even at an extremely high pressure of 272 kPa. Our sensor can be used to monitor diverse stimuli from a low to a high pressure range including weak gas flow, acoustic sound, wrist pulse pressure, respiration, and foot pressure with a single device.

Molecular dynamics for linear polymer melts in bulk and confined systems under shear flow.

In this work, we analyzed the individual chain dynamics for linear polymer melts under shear flow for bulk and confined systems using atomistic nonequilibrium molecular dynamics simulations of unentangled (C50H102) and slightly entangled (C178H358) polyethylene melts. While a certain similarity appears for the bulk and confined systems for the dynamic mechanisms of polymer chains in response to the imposed flow field, the interfacial chain dynamics near the boundary solid walls in the confined system are significantly different from the corresponding bulk chain dynamics. Detailed molecular-level analysis of the individual chain motions in a wide range of flow strengths are carried out to characterize the intrinsic molecular mechanisms of the bulk and interfacial chains in three flow regimes (weak, intermediate, and strong). These mechanisms essentially underlie various macroscopic structural and rheological properties of polymer systems, such as the mean-square chain end-to-end distance, probability distribution of the chain end-to-end distance, viscosity, and the first normal stress coefficient. Further analysis based on the mesoscopic Brightness method provides additional structural information about the polymer chains in association with their molecular mechanisms.

The mitochondrial genome of the smaller tea tortrix Adoxophyes honmai (Lepidoptera: Tortricidae).

Almost complete mitochondrial genome from a representative of an insect order Lepidoptera, the smaller tea tortrix Adoxophyes honmai was determined. The 15,680 bp long A. honmai genome encodes 13 putative proteins, two ribosomal RNAs and 22 tRNAs. The nucleotide sequences of A. honmai mitochondrial DNA have been compared with those of five species from the Lepidoptera and insects in the other orders that are available in the databases. The orientation and gene order of A. honmai is almost same to that of other insects with a few minor exceptions in the order of tRNAs and distribution of non-coding regions. Nucleotide composition, amino acid composition and codon usage are in the range of values estimated from other insect mitogenomes. In AT rich region of A. honmai, tandem reiterations are observed with repeats of TAA. In a preliminary phylogenetic analysis based on the concatenated 7 protein coding genes, A. honmai, an apoditrysian tortricid moth joined basally within the monophyly of Lepidoptera, supporting its relationship with other more derived species including obtectomeran Ostrinia species.

Review of Lecithoceridae (Lepidoptera: Gelechioidea) in the Oceanian Region, with description of a new species and a checklist of the family.

The Family Lecithoceridae of the Oceanian region, which includes New Guinea (Papua and Papua New Guinea) together with some islands east of Borneo and SW Pacific islands, is reviewed, with a description of Thubana brunalis Park, sp. nov. T. brunalis is the second species of the Torodorinae introduced to the region. Also included a historical review on the taxonomic works on the family in the region, a zoogeographical consideration of the taxa, and a tentative check list of the family, including 158 valid species names. Sphenocrates Meyrick, 1925, syn. nov. is synonymized with Crocanthes Meyrick. New combinations include Pectinimura palpella (Bradley, 1961), comb. nov. and Crocanthes neptis (Diakonoff, 1954), comb. nov.

Preserving and vouchering butterflies and moths for large-scale museum-based molecular research.

Butterflies and moths (Lepidoptera) comprise significant portions of the world's natural history collections, but a standardized tissue preservation protocol for molecular research is largely lacking. Lepidoptera have traditionally been spread on mounting boards to display wing patterns and colors, which are often important for species identification. Many molecular phylogenetic studies have used legs from pinned specimens as the primary source for DNA in order to preserve a morphological voucher, but the amount of available tissue is often limited. Preserving an entire specimen in a cryogenic freezer is ideal for DNA preservation, but without an easily accessible voucher it can make specimen identification, verification, and morphological work difficult. Here we present a procedure that creates accessible and easily visualized "wing vouchers" of individual Lepidoptera specimens, and preserves the remainder of the insect in a cryogenic freezer for molecular research. Wings are preserved in protective holders so that both dorsal and ventral patterns and colors can be easily viewed without further damage. Our wing vouchering system has been implemented at the University of Maryland (AToL Lep Collection) and the University of Florida (Florida Museum of Natural History, McGuire Center of Lepidoptera and Biodiversity), which are among two of the largest Lepidoptera molecular collections in the world.

Molecular identification of Adoxophyes honmai (Yasuda) (Lepidoptera: Tortricidae) based on mitochondrial COI gene sequences.

Molecular identification techniques are used where morphological characters are not useful for distinguishing species that resemble each other closely. The example studied here is the Adoxophyes species complex, in which A. orana (Fischer von Rösslerstamm) is officially the only known Korean species in the genus Adoxophyes (Lepidoptera: Tortricidae). However there have been suspicions that at least two types of A. orana exist in Korea based on the distribution and range of the host, with A. orana attacking apples and peaches, and another Adoxophyes sp. attacking tea and pears. The latter is presumed to be A. honmai (Yasuda), but the two have remained confused because of their extreme morphological similarity, despite several Asian studies of pheromonal and morphological characteristics. To confirm the occurrence of an Adoxophyes species other than A. orana in Korea, we compared 940 bp of the mitochondrial cytochrome oxidase I (COI) gene from 16 samples of Adoxophyes and found that there is a second Adoxophyes species different from A. orana. Comparison of the different sequences to that of Japanese A. honmai confirmed that they belong to the latter. From the sequence difference between the two Korean species, we were able to develop new PCR primer sets that distinguish them. This molecular identification technique with no enzyme digestion or sequencing step is a convenient and rapid way of differentiating between species that are hard to distinguish morphologically.