To segment defects from the quad flat non-lead QFN package surface a multilevel Otsu thresholding method based on the firefly algorithm with opposition-learning is proposed. First the Otsu thresholding algorithm is ex...To segment defects from the quad flat non-lead QFN package surface a multilevel Otsu thresholding method based on the firefly algorithm with opposition-learning is proposed. First the Otsu thresholding algorithm is expanded to a multilevel Otsu thresholding algorithm. Secondly a firefly algorithm with opposition-learning OFA is proposed.In the OFA opposite fireflies are generated to increase the diversity of the fireflies and improve the global search ability. Thirdly the OFA is applied to searching multilevel thresholds for image segmentation. Finally the proposed method is implemented to segment the QFN images with defects and the results are compared with three methods i.e. the exhaustive search method the multilevel Otsu thresholding method based on particle swarm optimization and the multilevel Otsu thresholding method based on the firefly algorithm. Experimental results show that the proposed method can segment QFN surface defects images more efficiently and at a greater speed than that of the other three methods.展开更多
Rayleigh waves have high amplitude, low frequency, and low velocity, which are treated as strong noise to be attenuated in reflected seismic surveys. This study addresses how to identify useful shear wave velocity pro...Rayleigh waves have high amplitude, low frequency, and low velocity, which are treated as strong noise to be attenuated in reflected seismic surveys. This study addresses how to identify useful shear wave velocity profile and stratigraphic information from Rayleigh waves. We choose the Firefly algorithm for inversion of surface waves. The Firefly algorithm, a new type of particle swarm optimization, has the advantages of being robust, highly effective, and allows global searching. This algorithm is feasible and has advantages for use in Rayleigh wave inversion with both synthetic models and field data. The results show that the Firefly algorithm, which is a robust and practical method, can achieve nonlinear inversion of surface waves with high resolution.展开更多
[Objective] The aim was to study cloning and prokaryotic expression of P23 major surface protein gene of Theileria sergenti. [Method] A pair of specific primers was designed according to the sequence of P23 major surf...[Objective] The aim was to study cloning and prokaryotic expression of P23 major surface protein gene of Theileria sergenti. [Method] A pair of specific primers was designed according to the sequence of P23 major surface protein of T. sergenti (D84447).The P23 gene was amplified by PCR from genomic DNA of T. sergenti and cloned into pMD18-T vector to construct recombinant clonal vector pMD18-P23. Positive clones were identified by PCR screening and restriction digestion. A recombinant expression plasmid pGEX-4T-P23 was constructed by subcloning the cloned P23 gene into the linearized pGEX-4T-1 vector and transformed into E. coli BL21. After introduction by IPTG,the expressed fusion protein was identified by SDS-PAGE and Western-blotting. [Result] The cloned gene has a total length of 507 bp. Sequencing result showed that the nucleotide sequence of the cloned P23 gene shared 99.4% identity with that of P23 published in GenBank (D84447). The expressed fusion protein was 46 ku in molecular mass. Induction opportunity of zhours after culture inoculation was the best,the induction time of 6 h was the best,and induction temperature of 34 ℃ was the best as well,IPTG of 1 mmol/L had little effect on the expression. Western-blotting indicated that recombinant protein was recognized by specific antibody. [Conclusion] This study would lay a foundation for further research on the prevention and diagnose of T. sergenti.展开更多
Trumpet shell, Charonia sauliae, is an endangered and valuable species, but its artificial propagation protocol has not been successfully established. To estimate the possibility of cryopreservation for larvae of C. s...Trumpet shell, Charonia sauliae, is an endangered and valuable species, but its artificial propagation protocol has not been successfully established. To estimate the possibility of cryopreservation for larvae of C. sauliae, which is a potential preparation for its artificial reproduction and further research, in this study a protocoi for the cryopreservation of veliger larvae of trumpet shell was optimized. Through a two-step cryopreservation procedure, four kinds of cryoprotectants (ethylene glycol, 1, 2-propanediol, dimethyl sulfoxide and glycerol) were employed at three concentrations (1.0, 1.5 and 2.0molL^-1) respectively and survival rates of larvae were determined after a storage of lh. The larvae frozen with these four cryoprotectants after 1 h storage were cultured, and then survival rates were determined at 24, 72 and 120 h after thawing. Dimethyl sulfoxide at a concentration of 1.5 molL^-1 showed the best protective effect in all experiments (p〈0.05). And survival rates of larvae frozen with dimethyl sulfoxide were determined after 1, 7 and 15 d of storage. The survival rates of larvae frozen with 1.5 molL^-1 dimethyl sulfoxide after 1 h, 1 d, 7 d and 15 d of storage were 80.77% ±7.51%, 80.34%±11.28%, 83.10%±9.14% and 77.23%±6.22% respectively. No significant differences in survival rates of larvae frozen with dimethyl sulfoxide were observed after various storage periods (p〉0.05).展开更多
The SOX2 protein is an important transcription factor functioning during the early development of animals. In this study, we isolated a full-length c DNA sequence of scallop Chlamys farreri sox2, Cf-sox2 which was 219...The SOX2 protein is an important transcription factor functioning during the early development of animals. In this study, we isolated a full-length c DNA sequence of scallop Chlamys farreri sox2, Cf-sox2 which was 2194 bp in length with a 981 bp open reading frame encoding 327 amino acids. With real-time PCR analysis, it was detected that Cf-sox2 was expressed in unfertilized oocytes, fertilized eggs and all the tested embryos and larvae. The expression level increased significantly(P < 0.01) in embryos from 2-cell to blastula, and then decreased significantly(P < 0.01) and reached the minimum in umbo larva. Moreover, location of the Cfsox2 expression was revealed using whole mount in situ hybridization technique. Positive hybridization signal could be detected in the central region of unfertilized oocytes and fertilized eggs, and then strong signals dispersed throughout the embryos from 2-cell to gastrula. During larval development, the signals were concentrated and strong signals were restricted to 4 regions of viscera mass in veliger larva. In umbo larva, weak signals could be detected in regions where presumptive visceral and pedal ganglia may be formed. The expression pattern of Cf-sox2 during embryogenesis was similar to that of mammal sox2, which implied that Cf-SOX2 may participate in the regulation of early development of C. farreri.展开更多
Recent trend for the control of insect pests has been towards the use of substances of plant origin. Reductionin fertility was determined in red flour beetle, Tribolium castaneum (Herbst.) by Nerium indicum Millleav...Recent trend for the control of insect pests has been towards the use of substances of plant origin. Reductionin fertility was determined in red flour beetle, Tribolium castaneum (Herbst.) by Nerium indicum Millleaves extract compared with coopex applied by contact method under laboratory condition. When adults were placed on filter paper treated With 7.86, 9.43, 11.01, 12.58 and 14.15 μL/cm2 doses of N. indicum leaves extract, fertility was 154 ± 15.2, 139 ± 15.0, 126 ± 6.0, 89 ± 12.2 and 72 ± 13.6 larvae/pair, compared with untreated and controls fertility (233 ± 16.0 and 190 ± 15.1 larvae/pair, respectively). However, the reduction in fertility was 33.2 ± 6.4%, 39.7 ± 3.7%, 45.7 ± 2.9%, 58.0 ± 4.4% and 66.3 ± 5.1% by the same doses ofN. indicum extract. Moreover, adults treated with the same doses of coopex with the same method, fertility was 160 ± 14.6, 154 ± 9.3, 140 ± 11.2, 113 ± 7.5 and 71 ±- 4.8 larvae/pair, compared with controls fertility (211 ± 8.5 larvae/pair), respectively. Furthermore, reduction in fertility was 24.3 ± 5.2%, 30.2 ± 6.4%, 37.2 ± 8.0%, 51.3 ± 1.4% and 58.8 ± 4.7% by the same doses of coopex. Minimum fertility was found in August and maximum was in July in both, N. indicum extract and coopex treated batches. The trend of reduction in fertility was the same in both N. indicum leaves extract and coopex, i.e., it was increased gradually from lower to higher doses. Nerium indicum leaves extract reduced fertility significantly compared with coopex.展开更多
The determination of pesticide residue on agricultural products is increasingly important. Exposure to pesticides can cause severe acute reactions in humans, including aplastic anemia and leukemia. In this work, we de...The determination of pesticide residue on agricultural products is increasingly important. Exposure to pesticides can cause severe acute reactions in humans, including aplastic anemia and leukemia. In this work, we developed a rapid and sensitive method to detect acetamiprid pesticide residue based on surface-enhanced Raman scattering. Silver nanorod (AgNR) arrays were fabricated by oblique angle deposition technology and were used as SERS substrates. Prior to detection, the AgNR arrays were cleaned with nitric acid solution or a mixture of methanol and acetone. Compared to the unwashed AgNR arrays, the AgNR arrays washed with methanol and acetone shows a signal enhancement 1000 times greater than the unwashed AgNR array due to the effective removal of the impurities on its surface. The limit of detection of acetamiprid was determined to be 0.05 mg/L. In addition, the molecular structure of acetamiprid was simulated and the corresponding vibration modes of the characteristic bands of acetamiprid were calculated by density function theory. To demonstrate its practical application, the AgNRs array substrates were applied successfully to the rapid identification of acetamiprid residue on a cucumber's surface. These results confirmed possibility of utilizing the AgNRs SERS substrates as a new method for highly sensitive pesticide residue detection.展开更多
Changes in sea surface temperature (SST), seawater oxygen isotope (δ18Osw), and local salinity proxy (δ18Osw-ss ) in the past 155 ka were studied using a sediment core (MD06-3052) from the northern edge of t...Changes in sea surface temperature (SST), seawater oxygen isotope (δ18Osw), and local salinity proxy (δ18Osw-ss ) in the past 155 ka were studied using a sediment core (MD06-3052) from the northern edge of the western Pacific Warm Pool (WPWP), within the flow path of the bifurcation of the North Equatorial Current. Our records reveal a lead-lag relationship between paired Mg/Ca-SST and δ18O during Termination II and the last interglacial period. Similarity in SST between our site and the Antarctic temperature proxy and in CO2 profile showed a close connection between the WPWP and the Antarctic. Values of 818Osw exhibited very similar variations to those of mean ocean δ18Osw, owing to the past sea-level changes on glacial-interglacial timescale. Calculated values of δ18O reflect a more saline condition during high local summer insolation (SI) periods. Such correspondence between δ18O and local SI in the WPWP may reflect complex interaction between ENSO and monsoon, which was stimulated by changes in solar irradiance and their influence on the local hydrologic cycle. This then caused a striking reorganization of atmospheric circulation over the WPWP.展开更多
The objective of this research is to investigate the impact of infection by the long-headed flour beetle m the specification of flour and its products, during three periods of infection 20, 40 and 60 days, which was c...The objective of this research is to investigate the impact of infection by the long-headed flour beetle m the specification of flour and its products, during three periods of infection 20, 40 and 60 days, which was confirmed by experiments, as was the impact of periods 40 and 60 days are clear, and that laboratory tests showed a significant decrease in weight, volume and specific volume of the loaf manufactured of infested flour as comparing with an uninfected one. The weight of the original sample was 150 g., has dropped to 135 g for the 60 days infection period and 35 ℃ of incubator. Deterioration of external features of the manufactured loaf also appeared (color, crust appearance, degree of baking and proliferation line), and attributes of the interior (granulation, color, smell and test of pulp). The total sample size was 465 mL while it was 288.9 mL for the 60 days infected sample. The color of flour also changed at the same period of infection and reached 6.61 stacks, while that of the uninfected was 3.7 stacks. The proportion of protein for the infected flour dipped to 21.39% as comparing with 28% for the health sound. The Amylograph, Farinograph and Extensograph tests showed considerable differences for many characters of dough made by the infected and non-infected flour. For example the value of B.U. was 980 for the infected flour and 560 B.U. for the uninfected one, and the arrival time was 4.18 min for the 60 days infection and 1.3 rain for the healthy. Also the value of the Critical Coefficient of Dough was 188 B.U. as compared with 64 B.U. for the uninfected sample.展开更多
The objective of this research is to investigate the impact of infestation by the confused flour beetle Tribolium confusum on the specification of flour and its product. The results of this work showed that infestatio...The objective of this research is to investigate the impact of infestation by the confused flour beetle Tribolium confusum on the specification of flour and its product. The results of this work showed that infestation by the confused flour beetle with 5 pairs of adult stage and its progeny within 3 months period may cause high deterioration and damaged of the flour specification. The people in lraq get their flour from some official and non-official mills which they produce not so good quality of this flour in addition to which it contains some times an infestation with the two species of the flour beetles T. castaneum and T. confusum, when people do not use this quantity as quickly as possible during this period of storage, the beetles will be increased in numbers and make the flour unacceptable for any kind of pastes or bread. The infestation by this beetle causes great pollution to the flour by the ecdysial of larvae and a bad smell that it leaves on the flour and all its products.展开更多
Five concentrations effects of nine herb powders against the confused flour beetle T. confusum have been studied under controlled conditions. The insecticidal effects of using powders on the egg, larval, pupal and adu...Five concentrations effects of nine herb powders against the confused flour beetle T. confusum have been studied under controlled conditions. The insecticidal effects of using powders on the egg, larval, pupal and adult stages of the insect showed that some of which (e.g., Foeniculum capillaceum and Anethum graveolens) have certain effects on the different stages of the studied insect even at the lowest concentrations. The mentioned herb powders showed very high mortality for egg stage reached 96.6% and 93.3% respectively at the lowest concentration and 100% at the highest concentration for both powders. Other powdered herbs showed prolonged effect of durations for larval stage. For example, Acorus calamus prolonged this duration to 34.2 days, at the first concentration while it was 25.4 days for control treatment. At the second concentration it was 53 and 41.5 days for An. gr. and Pimpinella anisum respectively, also Matricaria chamomilla showed similar effect at the 4th and 5th concentrations. Comparing with high numbers of progeny for the control treatment, also some powdered herbs showed high effect on respiration of the adults. The quantity of oxygen consumed by untreated beetles during the time of experiment (90 min) was so high than that of beetles treated with Ac. caL, Artemisia absinthium and AL sat. Moreover the internal systems of both sex males and females have been affected, ducts showing different changes when studied anatomically giving small size of ovarioles, deformed of accessory glands, swollen of stink glands with liquid oil. Majority of those males showed small testis. Most of the mentioned effects were happened as results of the powders of A c. cal., Al. sat., and Ma. ch., also the powders of F. cap., and A. abs., decrease the sizes of the testis, and accessory glands.展开更多
The sedimentary facies of the subaqueous Changjiang (Yangtze) River delta since the late Pleistocene was studied based on lithology and foraminifera analysis for two boreholes, CJK07 and CJK11, along with 14C dating...The sedimentary facies of the subaqueous Changjiang (Yangtze) River delta since the late Pleistocene was studied based on lithology and foraminifera analysis for two boreholes, CJK07 and CJK11, along with 14C dating. Four sedimentary facies were identified, namely fluvial, tidal flat, offshore, and prodelta facies. The fluvial sedimentary facies is comprised of fluvial channel lag deposits, fluvial point bar deposits, and floodplain deposits, showing a fining-upward sequence in general with no benthic foraminifera. A layer of stiff clay overlies the fluvial deposits in core CJK07, indicating a long-term exposure environment during the Last Glacial Maximum (LGM). During the postglacial sea-level rise around 13-7.5 cal ka BP, the tidal flat facies was deposited in core CJK11, characterized by abundant silt-clay couplets. Euryhaline species dominate the subtidal fiat foraminiferal assemblages, while almost no foraminifera was found in the intertidal fiat. The offshore environment was the major sedimentary environment when the sea level reached its highest level around 7.5 cal ka BP, with a maximum accumulation rate of 10 mm/a found in core CJK11. Prodelta sediments have been deposited in core CJK11 since -3 cal ka BP, after the formation of the Changjiang River delta. The difference in sedimentary facies between core CJK07 and CJK11 is due to their location: core CJK07 was in an interfluve while core CJK11 was in an incised valley during the LGM. Furthermore, AMS 14C dating of core CJK07 shows poor chronological order, indicating that the sediments were reworked by strong tidal currents and that sediment deposited since -7.7 cal ka BP in core CJK07 was eroded away by modem hydrodynamic forces caused by the southward shift of the Changjiang River delta depocenter.展开更多
Ciliates are very important components in most marine ecosystem. They are trophic link between the microbial food web and grazing food chain. In this study, ciliates were collected from 11 sites in the southern South ...Ciliates are very important components in most marine ecosystem. They are trophic link between the microbial food web and grazing food chain. In this study, ciliates were collected from 11 sites in the southern South China Sea (SCS) during August 25 to September 28, 2011. Their composition and distribution at the surface and 75m deep depth of the ocean were studied. A total of 30 species belonging to 22 genera were identified, and 22 species of 15 genera were Tintinnids. Eutintinnusfraknoii and E. stramentus were the most common species. The other dominants were strombidiids ciliates including Strombidium conicum and S. globosaneum, which were followed by the tide form, Mesodinium pulex. Ciliates abundance ranged from 46 indL-1 to 368 indL-1 in the open sites, 46-368indL-1 at surface and 73-198indL-1 at 75m deep layer. In the Yongshu reef, ciliates abundance ranged from 167indL-1 to 365 ind L-1 in the water colunm, similar to that in Sanya coral reef waters. Ciliates composition showed obvious difference between surface and 75m deep layer at station S2 (P〈0.05), while no similar result was observed at other sites. At 75m deep layer, salinity was negatively related to mixed layer depth (P〈 0.05), but positively to chlorophyll a concentration (P〈 0.05), indicating that the change of vertical mixing in water column influenced vertical distribution of ciliates in the southern SCS.展开更多
基金The National Natural Science Foundation of China(No.50805023)the Science and Technology Support Program of Jiangsu Province(No.BE2008081)+1 种基金the Transformation Program of Science and Technology Achievements of Jiangsu Province(No.BA2010093)the Program for Special Talent in Six Fields of Jiangsu Province(No.2008144)
文摘To segment defects from the quad flat non-lead QFN package surface a multilevel Otsu thresholding method based on the firefly algorithm with opposition-learning is proposed. First the Otsu thresholding algorithm is expanded to a multilevel Otsu thresholding algorithm. Secondly a firefly algorithm with opposition-learning OFA is proposed.In the OFA opposite fireflies are generated to increase the diversity of the fireflies and improve the global search ability. Thirdly the OFA is applied to searching multilevel thresholds for image segmentation. Finally the proposed method is implemented to segment the QFN images with defects and the results are compared with three methods i.e. the exhaustive search method the multilevel Otsu thresholding method based on particle swarm optimization and the multilevel Otsu thresholding method based on the firefly algorithm. Experimental results show that the proposed method can segment QFN surface defects images more efficiently and at a greater speed than that of the other three methods.
基金supported by the National Basic Research Program of China(No.2013CB228602)the National Science and Technology Major Project of China(No.2011ZX05004-003)the National High Technology Research Program of China(No.2013AA064202)
文摘Rayleigh waves have high amplitude, low frequency, and low velocity, which are treated as strong noise to be attenuated in reflected seismic surveys. This study addresses how to identify useful shear wave velocity profile and stratigraphic information from Rayleigh waves. We choose the Firefly algorithm for inversion of surface waves. The Firefly algorithm, a new type of particle swarm optimization, has the advantages of being robust, highly effective, and allows global searching. This algorithm is feasible and has advantages for use in Rayleigh wave inversion with both synthetic models and field data. The results show that the Firefly algorithm, which is a robust and practical method, can achieve nonlinear inversion of surface waves with high resolution.
基金Supported by Science and Technology Development Program of Jilin Province (20050703-4)~~
文摘[Objective] The aim was to study cloning and prokaryotic expression of P23 major surface protein gene of Theileria sergenti. [Method] A pair of specific primers was designed according to the sequence of P23 major surface protein of T. sergenti (D84447).The P23 gene was amplified by PCR from genomic DNA of T. sergenti and cloned into pMD18-T vector to construct recombinant clonal vector pMD18-P23. Positive clones were identified by PCR screening and restriction digestion. A recombinant expression plasmid pGEX-4T-P23 was constructed by subcloning the cloned P23 gene into the linearized pGEX-4T-1 vector and transformed into E. coli BL21. After introduction by IPTG,the expressed fusion protein was identified by SDS-PAGE and Western-blotting. [Result] The cloned gene has a total length of 507 bp. Sequencing result showed that the nucleotide sequence of the cloned P23 gene shared 99.4% identity with that of P23 published in GenBank (D84447). The expressed fusion protein was 46 ku in molecular mass. Induction opportunity of zhours after culture inoculation was the best,the induction time of 6 h was the best,and induction temperature of 34 ℃ was the best as well,IPTG of 1 mmol/L had little effect on the expression. Western-blotting indicated that recombinant protein was recognized by specific antibody. [Conclusion] This study would lay a foundation for further research on the prevention and diagnose of T. sergenti.
文摘Trumpet shell, Charonia sauliae, is an endangered and valuable species, but its artificial propagation protocol has not been successfully established. To estimate the possibility of cryopreservation for larvae of C. sauliae, which is a potential preparation for its artificial reproduction and further research, in this study a protocoi for the cryopreservation of veliger larvae of trumpet shell was optimized. Through a two-step cryopreservation procedure, four kinds of cryoprotectants (ethylene glycol, 1, 2-propanediol, dimethyl sulfoxide and glycerol) were employed at three concentrations (1.0, 1.5 and 2.0molL^-1) respectively and survival rates of larvae were determined after a storage of lh. The larvae frozen with these four cryoprotectants after 1 h storage were cultured, and then survival rates were determined at 24, 72 and 120 h after thawing. Dimethyl sulfoxide at a concentration of 1.5 molL^-1 showed the best protective effect in all experiments (p〈0.05). And survival rates of larvae frozen with dimethyl sulfoxide were determined after 1, 7 and 15 d of storage. The survival rates of larvae frozen with 1.5 molL^-1 dimethyl sulfoxide after 1 h, 1 d, 7 d and 15 d of storage were 80.77% ±7.51%, 80.34%±11.28%, 83.10%±9.14% and 77.23%±6.22% respectively. No significant differences in survival rates of larvae frozen with dimethyl sulfoxide were observed after various storage periods (p〉0.05).
基金supported by the National High Technology Research and Development Program of China(863 Program)(2012AA10A402)
文摘The SOX2 protein is an important transcription factor functioning during the early development of animals. In this study, we isolated a full-length c DNA sequence of scallop Chlamys farreri sox2, Cf-sox2 which was 2194 bp in length with a 981 bp open reading frame encoding 327 amino acids. With real-time PCR analysis, it was detected that Cf-sox2 was expressed in unfertilized oocytes, fertilized eggs and all the tested embryos and larvae. The expression level increased significantly(P < 0.01) in embryos from 2-cell to blastula, and then decreased significantly(P < 0.01) and reached the minimum in umbo larva. Moreover, location of the Cfsox2 expression was revealed using whole mount in situ hybridization technique. Positive hybridization signal could be detected in the central region of unfertilized oocytes and fertilized eggs, and then strong signals dispersed throughout the embryos from 2-cell to gastrula. During larval development, the signals were concentrated and strong signals were restricted to 4 regions of viscera mass in veliger larva. In umbo larva, weak signals could be detected in regions where presumptive visceral and pedal ganglia may be formed. The expression pattern of Cf-sox2 during embryogenesis was similar to that of mammal sox2, which implied that Cf-SOX2 may participate in the regulation of early development of C. farreri.
文摘Recent trend for the control of insect pests has been towards the use of substances of plant origin. Reductionin fertility was determined in red flour beetle, Tribolium castaneum (Herbst.) by Nerium indicum Millleaves extract compared with coopex applied by contact method under laboratory condition. When adults were placed on filter paper treated With 7.86, 9.43, 11.01, 12.58 and 14.15 μL/cm2 doses of N. indicum leaves extract, fertility was 154 ± 15.2, 139 ± 15.0, 126 ± 6.0, 89 ± 12.2 and 72 ± 13.6 larvae/pair, compared with untreated and controls fertility (233 ± 16.0 and 190 ± 15.1 larvae/pair, respectively). However, the reduction in fertility was 33.2 ± 6.4%, 39.7 ± 3.7%, 45.7 ± 2.9%, 58.0 ± 4.4% and 66.3 ± 5.1% by the same doses ofN. indicum extract. Moreover, adults treated with the same doses of coopex with the same method, fertility was 160 ± 14.6, 154 ± 9.3, 140 ± 11.2, 113 ± 7.5 and 71 ±- 4.8 larvae/pair, compared with controls fertility (211 ± 8.5 larvae/pair), respectively. Furthermore, reduction in fertility was 24.3 ± 5.2%, 30.2 ± 6.4%, 37.2 ± 8.0%, 51.3 ± 1.4% and 58.8 ± 4.7% by the same doses of coopex. Minimum fertility was found in August and maximum was in July in both, N. indicum extract and coopex treated batches. The trend of reduction in fertility was the same in both N. indicum leaves extract and coopex, i.e., it was increased gradually from lower to higher doses. Nerium indicum leaves extract reduced fertility significantly compared with coopex.
基金supported by the National Natural Science Foundation of China (No.61575087, No.21505057, and No.61771227)the Natural Science Foundation ofJiangsu Province (No.BK20151164, No.BK20150227, and No.BK20170229)+2 种基金the Innovation Project of Jiangsu Province(No.KYLX16_1322)the Natural Science Foundation of the Jiangsu Higher Education Institutions (No.17KJB140007)Foundation of Xuzhou City (No.KC15MS030)
文摘The determination of pesticide residue on agricultural products is increasingly important. Exposure to pesticides can cause severe acute reactions in humans, including aplastic anemia and leukemia. In this work, we developed a rapid and sensitive method to detect acetamiprid pesticide residue based on surface-enhanced Raman scattering. Silver nanorod (AgNR) arrays were fabricated by oblique angle deposition technology and were used as SERS substrates. Prior to detection, the AgNR arrays were cleaned with nitric acid solution or a mixture of methanol and acetone. Compared to the unwashed AgNR arrays, the AgNR arrays washed with methanol and acetone shows a signal enhancement 1000 times greater than the unwashed AgNR array due to the effective removal of the impurities on its surface. The limit of detection of acetamiprid was determined to be 0.05 mg/L. In addition, the molecular structure of acetamiprid was simulated and the corresponding vibration modes of the characteristic bands of acetamiprid were calculated by density function theory. To demonstrate its practical application, the AgNRs array substrates were applied successfully to the rapid identification of acetamiprid residue on a cucumber's surface. These results confirmed possibility of utilizing the AgNRs SERS substrates as a new method for highly sensitive pesticide residue detection.
基金Supported by the National Natural Science Foundation of China(Nos.41230959,41076030,41106042,40906038,41206044)the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDA11030104)the Project of Global Change and Air-Sea Interaction
文摘Changes in sea surface temperature (SST), seawater oxygen isotope (δ18Osw), and local salinity proxy (δ18Osw-ss ) in the past 155 ka were studied using a sediment core (MD06-3052) from the northern edge of the western Pacific Warm Pool (WPWP), within the flow path of the bifurcation of the North Equatorial Current. Our records reveal a lead-lag relationship between paired Mg/Ca-SST and δ18O during Termination II and the last interglacial period. Similarity in SST between our site and the Antarctic temperature proxy and in CO2 profile showed a close connection between the WPWP and the Antarctic. Values of 818Osw exhibited very similar variations to those of mean ocean δ18Osw, owing to the past sea-level changes on glacial-interglacial timescale. Calculated values of δ18O reflect a more saline condition during high local summer insolation (SI) periods. Such correspondence between δ18O and local SI in the WPWP may reflect complex interaction between ENSO and monsoon, which was stimulated by changes in solar irradiance and their influence on the local hydrologic cycle. This then caused a striking reorganization of atmospheric circulation over the WPWP.
文摘The objective of this research is to investigate the impact of infection by the long-headed flour beetle m the specification of flour and its products, during three periods of infection 20, 40 and 60 days, which was confirmed by experiments, as was the impact of periods 40 and 60 days are clear, and that laboratory tests showed a significant decrease in weight, volume and specific volume of the loaf manufactured of infested flour as comparing with an uninfected one. The weight of the original sample was 150 g., has dropped to 135 g for the 60 days infection period and 35 ℃ of incubator. Deterioration of external features of the manufactured loaf also appeared (color, crust appearance, degree of baking and proliferation line), and attributes of the interior (granulation, color, smell and test of pulp). The total sample size was 465 mL while it was 288.9 mL for the 60 days infected sample. The color of flour also changed at the same period of infection and reached 6.61 stacks, while that of the uninfected was 3.7 stacks. The proportion of protein for the infected flour dipped to 21.39% as comparing with 28% for the health sound. The Amylograph, Farinograph and Extensograph tests showed considerable differences for many characters of dough made by the infected and non-infected flour. For example the value of B.U. was 980 for the infected flour and 560 B.U. for the uninfected one, and the arrival time was 4.18 min for the 60 days infection and 1.3 rain for the healthy. Also the value of the Critical Coefficient of Dough was 188 B.U. as compared with 64 B.U. for the uninfected sample.
文摘The objective of this research is to investigate the impact of infestation by the confused flour beetle Tribolium confusum on the specification of flour and its product. The results of this work showed that infestation by the confused flour beetle with 5 pairs of adult stage and its progeny within 3 months period may cause high deterioration and damaged of the flour specification. The people in lraq get their flour from some official and non-official mills which they produce not so good quality of this flour in addition to which it contains some times an infestation with the two species of the flour beetles T. castaneum and T. confusum, when people do not use this quantity as quickly as possible during this period of storage, the beetles will be increased in numbers and make the flour unacceptable for any kind of pastes or bread. The infestation by this beetle causes great pollution to the flour by the ecdysial of larvae and a bad smell that it leaves on the flour and all its products.
文摘Five concentrations effects of nine herb powders against the confused flour beetle T. confusum have been studied under controlled conditions. The insecticidal effects of using powders on the egg, larval, pupal and adult stages of the insect showed that some of which (e.g., Foeniculum capillaceum and Anethum graveolens) have certain effects on the different stages of the studied insect even at the lowest concentrations. The mentioned herb powders showed very high mortality for egg stage reached 96.6% and 93.3% respectively at the lowest concentration and 100% at the highest concentration for both powders. Other powdered herbs showed prolonged effect of durations for larval stage. For example, Acorus calamus prolonged this duration to 34.2 days, at the first concentration while it was 25.4 days for control treatment. At the second concentration it was 53 and 41.5 days for An. gr. and Pimpinella anisum respectively, also Matricaria chamomilla showed similar effect at the 4th and 5th concentrations. Comparing with high numbers of progeny for the control treatment, also some powdered herbs showed high effect on respiration of the adults. The quantity of oxygen consumed by untreated beetles during the time of experiment (90 min) was so high than that of beetles treated with Ac. caL, Artemisia absinthium and AL sat. Moreover the internal systems of both sex males and females have been affected, ducts showing different changes when studied anatomically giving small size of ovarioles, deformed of accessory glands, swollen of stink glands with liquid oil. Majority of those males showed small testis. Most of the mentioned effects were happened as results of the powders of A c. cal., Al. sat., and Ma. ch., also the powders of F. cap., and A. abs., decrease the sizes of the testis, and accessory glands.
基金Supported by the Marine Public Welfare Research Project(No.200805063)the National Natural Science Foundation of China(Nos.41076023 and 41106065)+1 种基金the Basic Fund Project of National Science and Technology Ministry(No.2008FY220300)the Coastal Investigation and Research Project of China(No.908-02-02-05)
文摘The sedimentary facies of the subaqueous Changjiang (Yangtze) River delta since the late Pleistocene was studied based on lithology and foraminifera analysis for two boreholes, CJK07 and CJK11, along with 14C dating. Four sedimentary facies were identified, namely fluvial, tidal flat, offshore, and prodelta facies. The fluvial sedimentary facies is comprised of fluvial channel lag deposits, fluvial point bar deposits, and floodplain deposits, showing a fining-upward sequence in general with no benthic foraminifera. A layer of stiff clay overlies the fluvial deposits in core CJK07, indicating a long-term exposure environment during the Last Glacial Maximum (LGM). During the postglacial sea-level rise around 13-7.5 cal ka BP, the tidal flat facies was deposited in core CJK11, characterized by abundant silt-clay couplets. Euryhaline species dominate the subtidal fiat foraminiferal assemblages, while almost no foraminifera was found in the intertidal fiat. The offshore environment was the major sedimentary environment when the sea level reached its highest level around 7.5 cal ka BP, with a maximum accumulation rate of 10 mm/a found in core CJK11. Prodelta sediments have been deposited in core CJK11 since -3 cal ka BP, after the formation of the Changjiang River delta. The difference in sedimentary facies between core CJK07 and CJK11 is due to their location: core CJK07 was in an interfluve while core CJK11 was in an incised valley during the LGM. Furthermore, AMS 14C dating of core CJK07 shows poor chronological order, indicating that the sediments were reworked by strong tidal currents and that sediment deposited since -7.7 cal ka BP in core CJK07 was eroded away by modem hydrodynamic forces caused by the southward shift of the Changjiang River delta depocenter.
基金supported by the National Basic Research Program of China (2014CB441500)Special Fund for Agro-scientific Research in the Public Interest (201403008)Major Project of Ministry of Agriculture (NFZX2013)
文摘Ciliates are very important components in most marine ecosystem. They are trophic link between the microbial food web and grazing food chain. In this study, ciliates were collected from 11 sites in the southern South China Sea (SCS) during August 25 to September 28, 2011. Their composition and distribution at the surface and 75m deep depth of the ocean were studied. A total of 30 species belonging to 22 genera were identified, and 22 species of 15 genera were Tintinnids. Eutintinnusfraknoii and E. stramentus were the most common species. The other dominants were strombidiids ciliates including Strombidium conicum and S. globosaneum, which were followed by the tide form, Mesodinium pulex. Ciliates abundance ranged from 46 indL-1 to 368 indL-1 in the open sites, 46-368indL-1 at surface and 73-198indL-1 at 75m deep layer. In the Yongshu reef, ciliates abundance ranged from 167indL-1 to 365 ind L-1 in the water colunm, similar to that in Sanya coral reef waters. Ciliates composition showed obvious difference between surface and 75m deep layer at station S2 (P〈0.05), while no similar result was observed at other sites. At 75m deep layer, salinity was negatively related to mixed layer depth (P〈 0.05), but positively to chlorophyll a concentration (P〈 0.05), indicating that the change of vertical mixing in water column influenced vertical distribution of ciliates in the southern SCS.