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Integrative taxonomy of Diamesus Hope, 1840 (Coleoptera: Silphinae) is presented. Adults of D. bimaculatus Portevin, 1914 (endemic to Taiwan) and D. osculans (Vigors, 1825) (widely distributed from northern India to Australia) are redescribed, keyed and figured, including characters of the male and female genitalia of both species. Variation in elytral maculation in D. osculans is discussed and illustrated. The absence of diagnostic differences of D. osculans var. reductus Pic, 1917 from D. osculans is discussed, and the former name is confirmed as a junior subjective synonym of D. osculans. Types of all three names available were studied; a lectotype and paralectotypes are designated for the name D. osculans var. bimaculatus Portevin, 1914. Molecular phylogenetic analysis confirms the genus Diamesus is sister group to the genus Necrodes Leach, 1815, and D. osculans and D. bimaculatus are two, well supported clades. Detailed data on the distribution of D. bimaculatus and D. osculans are presented and mapped. Species distribution models for both species were created and interpreted. Diamesus osculans is reported for the first time from India: Uttarakhand, China: Anhui, Hainan, Hunan, Jiangxi, Shaanxi and Zhejiang Provinces, and Australia: Victoria; it is also recently confirmed from Taiwan, being sympatric in distribution there with D. bimaculatus. Available data on the ecology and seasonality of both species of Diamesus are also discussed.

Shape memory polymers (SMPs) are currently investigated as potential materials for large deployable space structures [1–3]. The thermomechanical properties of these polymers significantly change on reaching their glass transition temperature, which yields the excellent feature of shape fixity and shape recovery [4]. As another aspect, the modulus of these materials is not sufficient since they are polymeric materials. In actual applications, the fiber reinforcement is effective for ensuring the sustainability of the deployed structures. However, while the fiber reinforcement has advantages for increasing the stiffness, it has a negative influence on the shape recovery behavior of SMPs. Experimental studies for shape memory polymer composite were conducted by Gall et al. [5, 6] for SiC powder-reinforced nanocomposite, Ohki et al. [7] for short-glass-fiber reinforcement, and Lan et al. [8] for SMP reinforced with plain-weave fabrics, and the increase of residual strain after shape recovery process was confirmed. In order to maximize both the stiffness and shape-recovery behavior of fiber-reinforced SMPs, it is essential to know how the fibers block the shape recovery behavior of polymers. However, the mechanism was not modeled. Therefore, we focus on the mechanism underlying the degradation of shape recovery behavior due to fiber reinforcement. To investigate this mechanism, we first conducted thermomechanical cycle tests for pure SMP and SMP reinforced with short-carbon fibers. We used polyurethane series of thermoset SMP, Diary MP-5510 (curing temperature 100 C), provided by SMP Technologies Inc. The cured polymer has a glass transition temperature of 55 C, and the temperature range of glass transition between glassy state and rubbery state is 30 C. Short carbon fibers T700S (Toray Industries Inc.) were embedded in the polymer. The fibers with approximately 5 mm length were randomly embedded in the prepolymer before curing, and the weight fraction of fibers was set to 0, 2, and 4 wt%. It should be noted that the bundle of carbon fibers (12,000 fibers) was embedded and not dispersed in these model experiments, as also modeled later. After curing, strip specimens were cut out (approximately 40 mm gauge length, 20 mm width, and 2 mm thickness in average). The following thermomechanical cycle was applied to these specimens using a tensile test machine (INSTRON 5566), as shown in Fig. 1

Discontinuous-glass-fiber-reinforced plastic (GFRP) composite material is widely used in industrial fields, mainly because glass fiber improves the strength and stiffness of polymer and because it is much less expensive than carbon fiber. It is thought that the use of long fiber is important in more efficiently improving the strength and stiffness of composites. In our previous study [1], we reported that the fracture mode of the discontinuous-fiber-reinforced composite changes from the matrix-cracking mode to the fiberbreaking mode (Fig. 1), when the aspect ratio for the fiber length to the fiber radius exceeds about 150. We also demonstrated that the strength is dramatically improved compared to the strength of the short fiber-reinforced composites and that the global load-sharing (GLS) model can roughly predict the strength (Fig. 2). Recently, Thomason [2, 3] produced the long discontinuous-fiberreinforced composites where the aspect ratio was about 250 and reported the stiffness and strength of the composites. In this article, we applied the GLS model to his experiments and discuss the validity of our models. First, we discuss the strength of unidirectional (UD) discontinuous-fiber-reinforced composites, rUD, based on the GLS assumption [4, 5]. We applied two types of GLS approaches to predict the composite strength. The GLS model focuses on one fragmented fiber (i.e., discontinuous fibers), aligned in the fiber axial direction, and neglects the interaction among fibers in the fiber cross-sectional direction. It predicts the composite’s strength by simulating the fiber damage evolution in such a fiber. One approach is based on Monte Carlo simulation [6] for fragmentation in a fiber in the composites. The other is based on the analytical model by Duva et al. [5]. (Hereafter, we refer to this as the DCW model.) Monte Carlo simulation deals with a detailed fiber stress distribution and fragment distribution, though multiple calculations are required for the prediction because it is a probabilistic approach. In contrast, the DCW model assumes an approximate stress distribution and fragment distribution, but it predicts the composite strength analytically. In simulating the fiber-damage evolution, the first approach utilized Monte Carlo simulation with the elastic– plastic hardening shear-lag model given by Okabe and Takeda [7]. The schematic of the elastic–plastic shear-lag model is illustrated in Fig. 3. The axial length of the model was set to 25 9 lf (lf is the length of discontinuous fiber), and the axial length was divided into 10,000 segments. The fiber ends in discontinuous-fiber-reinforced composites were represented by setting some random segments to the initially broken segments. Thus, the averaged length lf of the discontinuous fibers was related to the density of the initially broken segments introduced in the model. The transverse length of the matrix shear region in the model

Carbon fibre reinforced polymer specimens were used in double cantilever beam tests in order to investigate the influence of delamination characteristics on multiple signal features extracted from active thermography data. During mechanical loading, delamination opening and growth were induced, allowing controlled setting of different configurations. In addition to the standardised specimens, specimen geometries were altered to investigate delamination depth and influences from two overlapping delaminations in different depths. The thermography data was obtained from a measurement where the specimens were subjected to a rectangular long pulse emitted from a halogen light. From the data various signal features were extracted. Correlations between signal features such as phase angle difference and delamination opening were investigated. Furthermore, a comparison of the relation between extracted features allowed identifying different sections of the delamination, proving the methods applicability as a detailed classification tool. Due to the high number of features extracted robustness is increased.

Nature Communications 3: Article number: 648 (2012); Published 31 Jan 2012; Updated 23 Oct 2012 In Fig. 2b of this Article, the distribution map for Necrodes littoralis was inadvertently duplicated under the label Necrophila brunnicollis. The correct version of Fig. 2 appears below.

The evolution of flight is a key innovation that may enable the extreme diversification of insects. Nonetheless, many species-rich, winged insect groups contain flightless lineages. The loss of flight may promote allopatric differentiation due to limited dispersal power and may result in a high speciation rate in the flightless lineage. Here we show that loss of flight accelerates allopatric speciation using carrion beetles (Coleoptera: Silphidae). We demonstrate that flightless species retain higher genetic differentiation among populations and comprise a higher number of genetically distinct lineages than flight-capable species, and that the speciation rate with the flightless state is twice that with the flight-capable state. Moreover, a meta-analysis of 51 beetle species from 15 families reveals higher genetic differentiation among populations in flightless compared with flight-capable species. In beetles, which represent almost one-fourth of all described species, repeated evolution of flightlessness may have contributed to their steady diversification since the Mesozoic era., 甲虫の種多様化要因の新説～飛翔能力の退化が種分化を促進. 京都大学プレスリリース. 2012-02-01.