The larval midgut of diamondback moth, Plutella xylostella, is a dynamic tissue that interfaces with a diverse array of physiological and toxicological processes, including nutrient digestion and allocation, xenobiotic detoxification, innate and adaptive immune response, and pathogen defense. Despite its enormous agricultural importance, the genomic resources for P. xylostella are surprisingly scarce. In this study, a Bt resistant P. xylostella strain was subjected to the in-depth transcriptome analysis to identify genes and gene networks putatively involved in various physiological and toxicological processes in the P. xylostella larval midgut.Using Illumina deep sequencing, we obtained roughly 40 million reads containing approximately 3.6 gigabases of sequence data. De novo assembly generated 63,312 ESTs with an average read length of 416bp, and approximately half of the P. xylostella sequences (45.4%, 28,768) showed similarity to the non-redundant database in GenBank with a cut-off E-value below 10-5. Among them, 11,092 unigenes were assigned to one or multiple GO terms and 16,732 unigenes were assigned to 226 specific pathways. In-depth analysis indentified genes putatively involved in insecticide resistance, nutrient digestion, and innate immune defense. Besides conventional detoxification enzymes and insecticide targets, novel genes, including 28 chymotrypsins and 53 ABC transporters, have been uncovered in the P. xylostella larval midgut transcriptome; which are potentially linked to the Bt toxicity and resistance. Furthermore, an unexpectedly high number of ESTs, including 46 serpins and 7 lysozymes, were predicted to be involved in the immune defense.As the first tissue-specific transcriptome analysis of P. xylostella, this study sheds light on the molecular understanding of insecticide resistance, especially Bt resistance in an agriculturally important insect pest, and lays the foundation for future functional genomics research. In addition, current sequencing effort greatly enriched the existing P. xylostella EST database, and makes RNAseq a viable option in the future genomic analysis.

The elastic stress and strain fields of finite thickness large plate containing a hole are systematically investigated using 3D finite element method. It is found that the stress and strain concentration factors of the finite thickness plate are different even if the plate is in elasticity state except at notch root of plate surface. The maximum stress and strain do not always occur on the mid plane of plate. They occur on the mid plane only in thin plate. The maximum stress and strain concentration factors are not on mid plane and the locations of maximum stress and strain concentration factors are different in thick plate. The maximum stress and strain concentration factors of notch root increase from their plane stress value to their peak values, then decrease gradually with increasing thickness and tend to each constant related to Poisson's ratio of plate, respectively. The stress and strain concentration factors at notch root of plate surface are the same and are the monotonic descent functions of thickness. Their values decrease rapidly and tend to each constant related to Poisson's ratio with plate thickness increasing. The difference between maximum and surface value of stress concentration factor is a monotonic ascent function of thickness. The thicker the plate is or the larger the Poisson's ratio is, the larger the difference is. The corresponding difference of strain concentration factor is similar to the one of stress concentration factor. But the difference magnitude of stress concentration factor is larger than that of strain concentration factor in same plate.

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It is well established that aluminium (Al) and some heavy metals can elicit organic acid exudation from a range of species. In the present research we found that copper (Cu) can also induce organic acid exudation from the roots of wheat, rye, triticale, maize and soybean. Using intact wheat plants, we made a comparative study of Al‐ and Cu‐ induced organic acid exudation. In 5‐day‐old wheat seedlings, severe Cu stress (40 µM CuCl2) mainly induced the exudation of malate and citrate, and Al‐tolerant genotypes could release significantly greater amounts of malate than Al‐sensitive genotypes. The time course of the exudation of malate and citrate from the roots of 5‐day‐old seedlings of wheat (cv. Atlas) in 200 µM AlCl3 was similar to that in 40 µM CuCl2. In older wheat plants (15‐day‐old), moderate Cu stress (12 µM CuCl2) induced the exudation of large amounts of citrate and addition of Al or La sharply reduced Cu‐induced citrate exudation, while Cu or La did not affect Al‐induced malate efflux. When half of the root system of Atlas wheat was immersed in Al‐ or Cu‐containing solution and the remaining half in Al‐ or Cu‐free solution, organic acids were only exuded into the solution containing Al or Cu. This suggests that no long distance signal transport is involved in organic acid exudation induced by Al or Cu, and that direct contact of Al or Cu with plant roots is a prerequisite for the induction of organic acid exudation. The anion‐channel inhibitor niflumic acid (NIF) significantly stimulated the exudation of both citrate and malate from 5‐day‐old wheat seedlings under severe Al or Cu stress. Our results suggest that Cu‐induced organic acid efflux may be a common response, which may play a role in alleviating Cu toxicity in plants.

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Perovskite resistive random-access memory (RRAM) is a promising candidate for next-generation logic, adaptive and nonvolatile memory devices, because of its high ON/OFF ratio, low-cost fabrication, and good photoelectric regulation performance. In this work, a flexible transparent CsPbBr 3 quantum dots (QDs) mixed in graphene oxide (GO) RRAM device is introduced, which is controllable by both an electric field and illumination. Under illumination, the ON/OFF ratio of the Ag/CsPbBr 3 QDs:GO/ITO device is ≈1.4 × 10 7 , which is 1077 times larger than that in the dark condition (1.3 × 10 4 ). The SET/RESET voltages are +2.28/−2.04 V and +1.68/−1.08 V under the dark and illumination conditions, respectively. As a flexible memory device, the resistances are little affected by the bending curvatures and load-cycling. Before and after 10 4 bending cycles with a radius of 5 mm under illumination, the ON/OFF ratios keep in the same order, which are 2.5 × 10 7 and 2.3 × 10 7 , respectively. The ratio values are 8.8 × 10 4 and 2.9 × 10 4 under the dark condition, respectively. This innovative resistive memory based on the CsPbBr 3 QDs:GO hybrid film supports a huge space for the development of photoelectrical dual-controlled flexible RRAM devices.

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