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Prey-mediated effects of mCry51Aa2-producing cotton on the predatory nontarget bug Orius majusculus(Reuter)

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Insect Science 2023年第4期30卷 1191-1206页

作者： Anja Boss jorg romeis Michael Meissle Research Division Agroecology and Environment AgroscopeZurichSwitzerland Institute of Plant Sciences University of BernBernSwitzerland

Genetically engineered(GE)cotton,MON 88702,is protected against cer-tain sucking pests,such as plant bugs and thrips,by producing mCry51Aa2,a mod-ified protein from Bacillus thuringiensis(Bt).Predatory pirate bugs(Orius spp.),natural enemies contributing to biological pest control,are also sensitive to the insecti-cidal protein when exposed continuously to high *** evaluated effects of MON 88702 on Orius majusculus when fed prey types with different mCry51Aa2 *** neonates were provided exclusively Tetranychus urticae spider mites reared on MON 88702(high mCry51Aa2 content),adverse effects on predator survival and de-velopment were confirmed,compared with specimens fed prey from near-isogenic non-Bt *** fed a mixture of *** and Ephestia kuehniella eggs(mCry51Aa2-free),predator life table parameters were similar to the treatment where eggs were fed *** mCry51Aa2-containing spider mites were provided for a limited time at the beginning or the end of juvenile development,effects were less *** pirate bug nymphs showed similar consumption rates for prey from Bt and non-Bt cotton,choice experiments revealed a preference for *** eggs over spider *** larvae(Spodoptera littoralis,high mCry51Aa2 content)or cotton aphids(Aphis gossypii,mCry51Aa2-free)reared on MON 88702 as alternative prey did not result in adverse ef-fects on *** study suggests limited risk of mCry51Aa2-producing cotton for ***,because its sensitivity for the Bt protein is relatively low and its natural food consists of diverse prey species with varying concentrations of Bt protein.

关键词： ecosystem services environmental risk assessment enzyme-linked im-munosorbent assay(ELISA) genetically modified crops Heteroptera Anthocoridae tritrophic interactions

Tier-1 assays for assessing the toxicity of insecticidal proteins produced by genetically engineered plants to non-target arthropods

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Insect Science 2014年第2期21卷 125-134页

作者： Yun-He Li jorg romeis Kong-Ming Wu Yu-Fa Peng State Key Laboratory for Plant Diseases and Insect Pests Institute of Plant Protection Chinese Academy of Agricultural Sciences Beijing China Agroscope Reckenholz-Tanikon Research Station ART Zurich Switzerland

In assessing an insect-resistant genetically engineered （IRGE） crop before its commercialization, researchers normally use so-called ＂Tier-1 assays＂ as the initial step to determine the effects of the crop on non-target organisms. In these tests, the insecticidal proteins （IPs） produced by the IRGEs are added to the diets of test organisms in the laboratory. Test organisms in such assays can be directly exposed to much higher concentrations of the test IPs than they would encounter in the field. The results of Tier-1 assays are thus more conservative than those generated in studies in which the organisms are exposed to the IPs by feeding on IRGE plant tissue or in the case of predators or parasites, by feeding on invertebrate prey or hosts that have fed on IRGE plant tissue. In this report, we consider three important factors that must be considered in Tier-1 assays：（i） methods for delivery of the IP to the test organisms; （ii） the need for and selection of compounds used as positive controls; and （iii） methods for monitoring the concentration, stability and bioactivity of the IP during the assay. We also analyze the existing data from Tier-1 assays regarding the toxicity of Bt Cry proteins to non-target arthropod species. The data indicate that the widely used Bt proteins have no direct toxicity to non-target organisms

关键词： artificial diet Cry protein environmental risk assessment ELISA positivecontroll sensitive insect bioassay

Use of a dietary exposure system for screening of insecticidal compounds for their toxicity to the planthopper Laodelphax striatellus

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Insect Science 2014年第5期21卷 667-675页

作者： Zeng-Xia Wang Ke-Jian Lin jorg romeis Yong-Lei Liu Ze-Wen Liu Yun-He Li Yu-Fa Peng State Key Laboratory for Biology of Plant Diseases and Insect Pests Institute of Plant Protection Chinese Academy of Agricultural Sciences Beijing Nanjing Agricultural University Nanjing China Agroscope Reckenholz-Tanikon Research Station ART ZurichSwitzerland

We developed a dietary exposure assay for screening insecticidal compounds for their toxicity and for assessing the side effects of insecticidal proteins produced by genetically engineered （GE） plants on the planthopper Laodelphax striatellus Fallen. The fitness bioassay confirmed that the diet fulfills the requirements to be used in the dietary exposure system. To validate the efficacy of the dietary exposure system, nymphs of L. striatellus were fed diets treated with different concentrations of an inorganic stomach poison, potassium arsenate （PA）, or a cysteine protease inhibitor, E-64. The results showed that with increasing concentrations of E-64, the larval development time was prolonged, the adult weight was reduced and the survival rate of L. striatellus was decreased. Similarly the survival rates of L. striatellus consistently decreased with increasing PA content in the diet. The data indicate that the dietary exposure assay is able to detect the effects of insecticidal compounds on L. striatellus. Subsequently, this assay was successfully used for assessing the potential toxicity of Cry2Aa. The results showed that L. striatellus larvae were not negatively affected when fed the artificial diet containing purified Cry2Aa at 300 μg/g diet. In the assay, the stability and bioactivity of crystal （Cry） proteins in the food sources were confirmed by enzyme-linked immunosorbent assay and sensitive-insect bioassays. These results show that L. striatellus is not sensitive to Cry2Aa. We conclude that the dietary exposure system is valid and useful for assessing the toxicity of insecticidal compounds produced by GE plants on planthoppers.

关键词： Cry2Aa E-64 genetically engineered rice potassium arsenate risk assessment

Bringing epigenetics into the diagnostics of the andrology laboratory： challenges and perspectives

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Asian Journal of Andrology 2014年第5期16卷 669-674,I0006页

作者： Ruth Klaver jorg Gromoll Centre of Reproductive Medicine and Andrology University Clinics of MOnster MOnster Germany

Recent studies have shown significant associations of aberrant DNA methylation in spermatozoa with idiopathic male infertility, increased frequency of spontaneous abortions and imprinting disorders. Thus, the analysis of DNA methylation of specific genes in spermatozoa has the potential to become a new valuable diagnostic marker in clinical andrology. This perspective article discusses the current state and value of DNA methylation analysis in the diagnostic setup of infertile men and outlines challenges and perspectives. It highlights the potential of DNA methylation in andrological diagnostics and its putative benefit in the examination of hitherto idiopathic infertile patients is described.

关键词： DNA methylation male infertility spermatogenesis

Fundamental influences of particles on stirred and unstirred venting processes of foaming systems

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Frontiers of Chemical Science and Engineering 2014年第2期8卷 141-148页

作者： Henrik LEIMEISTER jorg STEINBACH Department of Process Engineering Technische Universitat Berlin Strage des 17. Juni 135 10623 Berlin Germany

Venting is the common safety measure to protect plant equipment against excessive overpressure. So far, scenarios in which particles were part of the system and should have been accounted for did ignore their presence; the scenarios were treated like a two-phase system. Current research shows that particles can have a major influence on the venting behaviour. Experimental results indicate that particles affect level swell and relief flow especially of foamy systems. Based on those results four different layers of influence of the particle have been identified and are presented in a first model. Based on this model recommendations for the development of new and more complex models are given.

关键词： venting multi-phase

The contribution of small leaks in a baghouse filter to dust emission in the PM2.s range-A system approach

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Particuology 2017年第1期15卷 40-52页

作者： Oliver Kurtz jorg Meyer Gerhard Kasper Institut for Mechanische Verfahrenstechnik und Mechanik Karlsruhe Institute of Technology 76131 Karlsruhe Germany Freudenberg Filtration Technologies 69465 WeinheimGermany.

The contribution of leakage in a baghouse filter （defined as a short circuit between the upstream and downstream sides of the filter） to the emission of fine particles is quantified in comparison to other dust emission sources, and the influence of key operating variables on overall system response is analyzed. The study was conducted on a well-maintained pilot-scale filter unit （9 bags of 500 g/m^2 calendered polyester needle felt; total surface area 4.2 m^2） operated in Ap-controlled mode over a range of pulsing intensities, with two types of test dust （one free-flowing and the other cohesive） at inlet concentrations of 10 and 30 g/m^3. Leaks included single holes between 0.5 and 4 mm diameter, intentionally placed in either the plenum plate or one of the filter bags, as well as seamlines from bag confectioning. Emissions were sep- arated by source into a transient contribution due to dust penetration through the filter bags after each cleaning pulse, and a continuous contribution from leaks. This separation was based on a novel method of data processing that relies on time-resolved concentration measurements with a specially calibrated optical particle counter. Tiny leaks on the order of 1 mm generated the same emission level as all the bags combined, and dominated continuous emissions. The equivalent leak cross section （leakage = media emission） was about 1 ppm of the total installed filter surface, independent of upstream dust concentra- tion. Leakage through open seamlines amounted to 75% of media emissions in case of free-flowing test dust. Leakage was restricted to aerodynamic diameters less than ~5 μm （roughly the PM2.s mass frac- tion）. For comparison, time-averaged mass penetration through conventional needle-felt media ranged from about 10^-5 to 10^-6, depending on cohesiveness of the particle material and pulse cleaning intensity, giving emission levels between about 0.02 and 0.2 mg/m^3 at the reference concentration of 10 R/m^2.

关键词： Air filtration Baghouse Pulse-cleaned filters Leaks PM2.5 Dust emission

Numerical analysis of hydroabrasion in a hydrocyclone

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Petroleum Science 2016年第2期13卷 304-319页

作者： Mehdi Azimian Hans-jorg Bart Department of Mechanical and Process Engineering University of Kaiserslautern 67663 Kaiserslautern Germany

The velocity profiles and separation efficiency curves of a hydrocyclone were predicted by an Euler-Euler approach using a computational fluid dynamics tool ANSYS-CFX 14.5. The Euler-Euler approach is capable of considering the particle-particle interactions and is appropriate for highly laden liquid-solid mixtures. Pre- dicted results were compared and validated with experi- mental results and showed a considerably good agreement. An increase in the particle cut size with increasing solid concentration of the inlet mixture flow was observed and discussed. In addition to this, the erosion on hydrocyclone walls constructed from stainless steel 410, eroded by sand particles （mainly SiOz）, was predicted with the Euler-La- grange approach. In this approach, the abrasive solid particles were traced in a Lagrangian reference frame as discrete particles. The increases in the input flow velocity, solid concentration, and the particle size have increased the erosion at the upper part of the cylindrical body of the hydrocyclone, where the tangential inlet flow enters the hydrocyclone. The erosion density in the area between the cylindrical to conical body area, in comparison to other parts of the hydrocyclone, also increased considerably. Moreover, it was observed that an increase in the particle shape factor from 0.1 to 1.0 leads to a decrease of almost 70 % in the average erosion density of the hydrocyclone wall surfaces.

关键词： Hydrocyclone Computational fluiddynamicS (CFD) Separation efficiency - Erosion rateErosion impact parameters

Studies of fiber-matrix debonding

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Frontiers of Structural and Civil Engineering 2015年第4期9卷 448-456页

作者： Navneet DRONAMRAJU Johannes SOLASS jorg HILDEBRAND Simulation und Experiment Bauhaus-Universitdt Weimar Weimar 99423 Germany

In this paper, the debonding of a single fiber-matrix system of carbon fiber reinforced composite (CFRP) AS4/Epson 828 material is studied using Cohesive Zone Model (CZM). The effect of parameters namely, maximum tangential contact stress, tangential slip distance and artificial damping coefficient on the debonding length at the interface of the fiber-matrix is analyzed. Contact elements used in the CZM are coupled based on a bilinear stress-strain curve. Load is applied on the matrix, tangential to the interface. Hence, debonding is observed primarily in Mode *** range of values are considered to study the inter-dependency of the parameters and its effect on debonding length. Out of the three parameters mentioned, artificial damping coefficient and tangential slip distance significantly affect debonding length. A thorough investigation is recommended for case wise interface debonding analysis, to estimate the optimal parametric values while using CZM.

关键词： single fibre cohesive zone model interface debonding carbon fiber reinforced composite (CFRP)

Amyloid β and free heme：bloody new insights into the pathogenesis of Alzheimer＇s disease

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Neural Regeneration Research 2018年第7期13卷 1170-1174页

作者： jorg Flemmig Marcel Zámocky A Alia Institute for Medical Physics and Biophysics Medical Faculty Leipzig University Leipzig Germany Institute of Molecular Biology Slovak Academy of Sciences Bratislava Slovakia Institute of Chemical Environmental and Biological Engineering Faculty of Technical Chemistry Vienna University of Technology Vienna Austria Leiden Institute of Chemistry Faculty of Science Leiden University Leiden The Netherlands

The cerebral formation of Amyloid β（Aβ） is a critical pathological feature of Alzheimer＇s disease（AD）.An accumulation of this peptide as senile plaques（SP） was already reported by Alois Alzheimer,the discoverer of the *** the exact contribution of Aβ to AD development remains ***,while extensive cerebral Aβ formation leads to fibril formation in many species,AD-like symptoms apparently depend on the highly conserved N-terminal residues R5,Y10 and *** amino acids were also shown to lead to the formation of Aβ-heme complexes,which exhibit peroxidase activity in the presence of H_2O_*** together these observations we propose that the formation and enzymatic activity of the named complexes may represent an essential aspect of AD ***,Aβ is also known to lead to cerebral micro-vessel destruction（CAA） as well as to hemolytic *** we suggest that the Aβ-derived cerebral accumulation of blood-derived free heme represents a likely precondition for the subsequent formation of Aβ-heme complexes.

关键词： Alzheimer's disease amyloid β sequence amyloid β-heme complexes peroxidase activity dityrosine formation cerebral amyloid angiopathy hemolysis