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The mud crab (Scylla paramamosain) is an economically important crab species that is distributed along the southern coast of China. Previously we reported that various morphological types of mud crabs differentially adapt to temperature changes. This study investigates the effects of temperature on morphs with one or two spines (Sp1 and Sp2, respectively) on the outer margin of the carpus of cheliped at a low temperature (8 °C) and a control temperature (20 °C). The hepatopancreas were the transcriptome source, and a total of 81,853 unigenes were obtained by sequencing, with an average length of 420 bp, and an N50 of 1460 bp. Of these, 22.33 % were known genes. Under low-temperature stress, there were 361 differentially expressed genes (DEGs) between the two morphs; 96 and 265 were up- and down-regulated genes, respectively. There were no DEGs between the morphs at 20 °C. Functional enrichment analysis revealed that the DEGs encoded abundant metallocarboxypeptidase activity, extracellular space, proteolysis, and sequence-specific DNA binding, and were further enriched in signal pathway components, including ubiquinone and other terpenoid-quinone biosynthesis, phenylalanine metabolism, MAPK signaling pathway, apoptosis, and other signaling pathways. The gene expressions of acid phosphatase (ACP), chymotrypsin (CHY), serine carboxypeptidase (SCP), and trypsin (TRY) under low-temperature stress were detected. The expressions of ACP, CHY, and SCP gradually decreased with time. The ACP, CHY, SCP, and TRY gene expression of the Sp1 morph was lower than that of the Sp2 morph; however, the ACP gene expression of the Sp1 morph was higher than that of the Sp2 morph at several time points. In conclusion, adaptability differences between the morphs to low-temperature stress were confirmed, which will enable the selection of cold-tolerant, high-quality varieties of mud crabs for breeding.

The relationship between diversity and invasibility might be confounded by extrinsic environmental factors and the evolutionary structure of the resident community. To examine the role of extrinsic environmental factors, species and phylogenetic diversity in regulating community susceptibility to invasion, we established 109 plots either with or without Ageratum conyzoides L. in Liandu, China. We identified all the species in our samples, weighed the aboveground biomass of each species, and measured environmental variables. For all species recorded in our survey, we constructed a community phylogeny using PhytoPhylo mega-phylogeny as a backbone. We selected the best-fit environment model based on the minimum corrected Akaike information criteria score to examine the effect of extrinsic environmental variables on the relative abundance of A. conyzoides. Relationship between biodiversity and invasion of A. conyzoides was examined by a multiple regression, in which extrinsic ecological factors and biodiversity were combined to predict the relative abundance of A. conyzoides. To reduce the number of extrinsic variables, the first six components produced by a principal component analysis of environmental variables were used as predictive variables in the multiple regression. The best-fit environment model indicated that the relative abundance of A. conyzoides was higher in summer and in communities with lower total organic matter and higher total nitrogen in the soil. The multiple regression indicated that only the positive relationship between the Shannon–Wiener diversity of exotics and the relative abundance of A. conyzoides was significant. This result challenges the importance of diversity–resistance to plant invasion. Generalist facilitation might exist between A. conyzoides and other exotic species, although mechanisms for such facilitation are unclear. Overall, our finding suggests the extrinsic factors covarying with diversity are more important than diversity itself in regulating community susceptibility to invasion.

Water-distilled essential oil from Clinopodium chinense (Labiatae) aerial parts at the flowering stage was analyzed by gas chromatography-mass spectrometry. Thirty-five compounds, accounting for 99.18% of the total oil, were identified, and the main components of the essential oil of C. chinense were spathulenol (18.54%), piperitone (18.9%), caryophyllene (12.04%), and bornyl acetate (8.14%). Based on bioactivity-directed fractionation, bornyl acetate, caryophyllene, and piperitone were identified from the essential oil. The essential oil possessed fumigant toxicity against booklice (Liposcelis bostrychophila) with a 50% lethal concentration (LC50) value of 423.39 μg/liter, while the isolated constituents, bornyl acetate and piperitone, had LC50 values of 351.69 and 311.12 μg/liter against booklice, respectively. The essential oil also exhibited contact toxicity against L. bostrychophila with an LC50 value of 215.25 μg/cm(2). Bornyl acetate, caryophyllene, and piperitone exhibited acute toxicity against booklice with LC50 values of 321.42, 275.00, and 139.74 μg/cm(2), respectively. The results indicated that the essential oil and its isolated constituents have potential for development into natural insecticides or fumigants for control of insects in stored grains.

BACKGROUND In our screening programme for new agrochemicals from wild plants, the essential oil of Tetradium glabrifolium (Champ. ex Benth.) T.G. Hartley fruits was found to possess strong larvicidal activity against the Asian tiger mosquito, Aedes albopictus L. The essential oil was extracted via hydrodistillation, and the constituents were determined by GC-MS analysis. The active compounds were isolated and identified by bioassay-directed fractionation. RESULTS GC-MS analyses revealed the presence of 19 components with 2-tridecanone (43.38%), 2-undecanone (24.09%), D-limonene (13.01%), caryophyllene (5.04%) and β-elemene (4.07%) being the major constituents. Bioactivity-directed chromatographic separation of the oil led to the isolation of 2-tridecanone, 2-undecanone and D-limonene as active compounds. The essential oil of T. glabrifolium exhibited larvicidal activity against the early fourth-instar larvae of A. albopictus, with an LC50 value of 8.20 µg mL−1. The isolated constituent compounds, 2-tridecanone, 2-undecanone and D-limonene, possessed strong larvicidal activity against the early fourth-instar larvae of A. albopictus, with LC50 values of 2.86, 9.95 and 41.75 µg mL−1 respectively. CONCLUSION The findings indicated that the essential oil of T. glabrifolium fruits and the three constituents have an excellent potential for use in control of A. albopictus larvae and could be useful in the search for newer, safer and more effective natural compounds as larvicides. © 2014 Society of Chemical Industry

The starch/lactic acid grafting copolymer has been prepared by one-step reaction of corn starch with lactic acid catalyzed with sulfuric acid, and the structure of product was characterized by IR, XRD, SEM and1H-NMR. The experimental results showed that sulfuric acid could catalyze the graft copolymerization of starch with lactic acid, and the grafting degree of starch could reach 55.4%.

In this article, the factors which have influence on the work roll thermal deformation in cold strip rolling and the heat transferring mechanism are discussed. It is considered that there are three directions, radial, axis and circumference, for heat transferring for work roll thermal deformation. Therefore, it is a three dimensions unstable system for work roll temperature field of cold strip rolling. The plastic deformation work and friction heat are calculated by the divided element and digital integration method. The simplified calculation model is built for the heat transferring along work roll. There are four zones for work roll heat transferring: roll gap zone, air zone, emulsion zone, rolls contact zone. The heat transferring between the zones is decided by the temperature difference. The inter temperature field and thermal deformation of work roll can be calculated by two-dimension finite difference method. The work roll temperature and thermal crown of actual application cold rolling mill are analyzed by the model. By the comparison between calculated values and measured values, the work roll thermal calculation model can meet the accuracy requirement of on-line control.

Purpose: To determine the insecticidal properties of essential oil from Mosla soochowensis aerial parts against two insect pests, Sitophilus zeamais and Tribolium castaneum . Methods: Hydro-distillation of M. soochowensis was used to extract the essential oil. Gas chromatography/mass spectrometry (GC/MS) analysis was performed, and the contact (topical application) and fumigant toxicity (sealed space) of the essential oil were evaluated. Results: Thirty-nine chemical compounds were identified by GC-MS analysis of M. soochowensis essential oil. The major components are β-caryophyllene (12.82 %), spatulenol (6.34 %), β-eudesmol (6.26 %), carvone (6.12 %), α-thujone (5.12 %), γ-eudesmol (4.86 %), α-cedrol (4.23 %), and α- caryophyllene (4.04 %). The plant essential oil exerted contact toxicity against adults of S. zeamais and T. castaneum (median lethal concentration (LC 50 ), 25.45 and 10.23 μg/adult, respectively). Moreover, the essential oil exhibited pronounced fumigant toxicity towards adults of both species (LC 50 12.19 and 10.26 mg/L air, respectively). Conclusion: These results show that M. soochowensis essential oil can be used in development of safer and more natural and effective fumigants/insecticides for stored products. Keywords: Mosla soochowensis , Contact toxicity, Sitophilus zeamais , Fumigant, Insecticide, Essential oil, Tribolium castaneum

Purpose: To investigate contact and fumigant toxicity of the essential oil of Bidens frondosa and its isolated constituents against booklice ( Liposcelis bostrychophila ). Methods: The essential oil of B. frondosa was obtained by hydro-distillation and analyzed by gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS) with HP-5MS column. The active constituents were purified from the oil by bioactivity-guided fractionation. Contact (impregnated filter paper method) and fumigant toxicity (sealed space) of the oil and its isolates were determined. Results: Thirty-two compounds, representing 98.88 % of the total oil, were determined and the major constituents of the essential oil were caryophyllene oxide (20.50 %), borneol (17.66 %), 4-terpineol (17.26 %), and β-cedrene (6.94 %). The essential oil displayed fumigant toxicity against booklice, with a median lethal concentration (LC 50 ) of 507.35 μg/L while the isolated constituents, borneol and 4-terpineol, had LC 50 values of 2.20 mg/L and 335.24 μg/L against booklice, respectively. The essential oil also exhibited contact toxicity against L. bostrychophila with an LC 50 value of 210.73 μg/cm 2 . Borneol, caryophyllene oxide, β-cedrene, and 4-terpineol showed acute toxicity against booklice with LC 50 of 98.04, 84.62, 458.79 and 211.35 μg/cm 2 , respectively. Conclusion: The results suggest that the essential oil and its isolates possess potential for cultivation into natural insecticides or fumigants, for control of insects in stored grains. Keywords: Bidens frondosa, Liposcelis bostrychophila , Contact toxicity, Essential oil, Boolice, Stored grains, Natural insecticides, Fumigants

In our screening programme for new agrochemicals from wild plants, the essential oil of Tetradium glabrifolium (Champ. ex Benth.) T.G. Hartley fruits was found to possess strong larvicidal activity against the Asian tiger mosquito, Aedes albopictus L. The essential oil was extracted via hydrodistillation, and the constituents were determined by GC-MS analysis. The active compounds were isolated and identified by bioassay-directed fractionation.GC-MS analyses revealed the presence of 19 components with 2-tridecanone (43.38%), 2-undecanone (24.09%), D-limonene (13.01%), caryophyllene (5.04%) and β-elemene (4.07%) being the major constituents. Bioactivity-directed chromatographic separation of the oil led to the isolation of 2-tridecanone, 2-undecanone and D-limonene as active compounds. The essential oil of T. glabrifolium exhibited larvicidal activity against the early fourth-instar larvae of A. albopictus, with an LC50 value of 8.20 µg mL(-1). The isolated constituent compounds, 2-tridecanone, 2-undecanone and D-limonene, possessed strong larvicidal activity against the early fourth-instar larvae of A. albopictus, with LC50 values of 2.86, 9.95 and 41.75 µg mL(-1) respectively.The findings indicated that the essential oil of T. glabrifolium fruits and the three constituents have an excellent potential for use in control of A. albopictus larvae and could be useful in the search for newer, safer and more effective natural compounds as larvicides.

The aim of this study was to evaluate the larvicidal activity of the essential oil of Youngia japonica aerial parts against the larvae of Aedes albopictus and to isolate any active compounds from the oil. Gas chromatography-mass spectrometry (GC-MS) analyses revealed the presence of 31 compounds, with menthol (23.53%), α-asarone (21.54%), 1,8-cineole (5.36%), and caryophyllene (4.45%) as the major constituents. Bioactivity-directed chromatographic separation of the oil led to the isolation of menthol and α-asarone as active compounds. The essential oil of Y. japonica exhibited larvicidal activity against the fourth instar larvae of A. albopictus with an LC50 value of 32.45 μg/mL. α-Asarone and menthol possessed larvicidal activity against the fourth instar larvae of A. albopictus with LC50 values of 24.56 μg/mL and 77.97 μg/mL, respectively. The results indicate that the essential oil of Y. japonica aerial parts and the two constituents can be potential sources of natural larvicides.

Purpose: To determine larvicidal activity of essential oil derived from Clinopodium gracile (Benth.) Matsum. (Labiatae) aerial parts against the larvae of Aedes albopictus Skuse． Methods: Essential oil of C. gracile aerial parts was obtained by hydrodistillation and analyzed by gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS). The activity of the essential oil was evaluated, using World Health Organization (WHO) procedures, against the fourth larvae of A. albopictus for 24 h and larval mortality recorded at a various essential oil concentrations ranging from 12.5 – 200.0 μg/mL. Results: A total of 34 components of the essential oil of C. gracile were identified. The essential oil has higher content of sesquiterpenoids (70.49 %) than monoterpenoids (12.21 %). The other principal compounds of the essential oil were germacrene D (20.59 %), nootkatone (8.22 %), morillol (7.74 %), βelemene (7.38 %), α-bergamotene (6.08 %), cis-β-farnesene (5.47 %) and caryophyllene (5.17 %). The essential oil exhibited larvicidal activity against A. albopictus with a median lethal concentration (LC50) of 42.56 μg/mL. Conclusion: The findings obtained indicate that the essential oil of C. gracile has potentials for use in the control of A. albopictus larvae and could be useful in the search for new, safer and more effective natural compounds as larvicides.