bluuebunny/crossref_metadata_2025_split huggingface dataset:
Design and use of a simulation model to evaluate germplasm for antibiotic resistance to the greenhouse whitefly (Trialeurodes vaporariorum) and the sweetpotato whitefly (Bemisia tabaci)
Authors: Van Giessen W. A. , Mollema C. , Elsey K. D. 
Published: April 2011

AbstractSARAH (Software for the Assessment of antibiotic Resistance to Aleyrodidae in Host plants) is a deterministic simulation model of whitefly population growth based on whitefly life‐history components determined on individual plants. The life‐history components recorded were oviposition rate, adult survival, pre‐adult survival, developmental period, and sex ratio. The simulation model serves as a tool to combine these components and to obtain a single criterion for (antibiotic) resistance. The criterion used was the decrease in simulated intrinsic population growth rate, rs, relative the rs value determined on a susceptible control genotype. This model‐based evaluation method was tested using the greenhouse whitefly, Trialeurodes vaporariorum Westwood, on tomato and the sweetpotato whitefly, Bemisia tabaci Gennadius, on tomato, eggplant, collard, and pepper.To study its consistency over time, the evaluation method was repeated six times for T. vaporariorum on a susceptible and a resistant tomato cultivar. Simulated intrinsic population growth rate was more consistent in indicating resistance than any of the individual life‐history components. Of ten L. hirsutum accessions tested for resistance to T. vaporariorum, three exhibited rs values that were significantly lower than those for the susceptible control. In addition, on these ten L. hirsutum accessions, a significant positive correlation was observed between rs and sex ratio (# females/# males).Four host plant species (tomato, collard, eggplant, and pepper) were evaluated for resistance to B. tabaci. All life‐history components and rs values varied among host species, while a negative rs value was observed for B. tabaci on pepper.A high correlation was found between results from a sensitivity analysis of SARAH and results from a sensitivity analysis of a validated whitefly population simulation model by Yano et al. (1989a). Significant correlations were found for the relationships between oviposition rate, adult survival, or pre‐adult survival and rs, indicating that none of these life‐history components can be omitted from the test procedure. This model‐based evaluation method offers a standardized way to quantify levels of antibiotic resistance to whiteflies and will enhance efficiency in breeding programs.
Mechanical and salivary aspects of potato leafhopper probing in alfalfa stems
Authors: Ecale Carol L. , Backus Elaine A. 
Published: April 2011

AbstractStudies were conducted to separate the salivary and mechanical aspects of probing damage by the potato leafhopper, Empoasca fabae (Harris) (Homoptera: Cicadellidae), to stem vascular tissue of alfalfa, Medicago sativa L. Implantation of salivary gland tissue or fed‐upon artificial diet under the stem epidermis yielded no evidence, three days later, of hopperburn‐associated, anatomical changes. Mechanical puncturing of stems with implements approximating the size and shape of leafhopper stylets caused some anatomical changes, three days later, similar to those underlying hopperburn, i.e. tracks of necrosis, chlorosis, cell enlargement, and cell division. These changes, however, were much less severe than those observed in tissues three days after potato leafhopper probing. In contrast, puncturing through salivary gland or Malpighian tubule tissues produced extreme hyperplasia and other symptoms of wounding in cells near the puncture. This was similar to but more severe than effects from leafhopper probing, and was probably caused by leafhopper structural tissues or larger amounts of saliva being conveyed into the plant than normally occurs during leafhopper probing. We conclude that both salivation and mechanical wounding by leafhopper stylets are probably necessary to cause hopperburn‐associated anatomical changes to vascular tissue in stems of alfalfa. This conclusion supports our hypothesis that hopperburn is a saliva‐enhanced wound response.
Life history and life table parameters of the predatory mite Typhlodromus talbii
Authors: Camporese Paolo , Duso Carlo 
Published: April 2011

AbstractThe predatory mite Typhlodromus talbii Athias‐Henriot occurs in European vineyards and is often associated with economically important species. Neither its role in vineyards nor the factors affecting its population dynamics and relationships with other phytoseiid species are well known. The development and the reproduction of T. talbii were studied in the laboratory by rearing the predator on different kinds of food (Panonychus ulmi, Eotetranychus carpini, Colomerus vitis, Tydeus caudatus, Mesembryanthemum criniflorum pollen). Overwintered females reared on tydeids survived for long periods and laid eggs, but they died after a few days when spider mites or pollen were provided. Development occurred on all mite species but not on pollen. Developmental times on tydeids were shorter than on the other prey. Oviposition was recorded on tydeids and, to a lesser extent, on eriophyids but not on spider mites or pollen. Experiments on tydeids, which resulted as being the best food, were conducted at two temperatures (20° and 27°C). The highest temperature affected the duration of development and oviposition rates positively, but total fecundity was similar. Predators reared at 27°C consumed more prey than those reared at 20°C. The life table parameters of the species were evaluated on T. caudatus (at 20° and 27°C) and on C. vitis. The highest rm of T. talbii was found for individuals reared on T. caudatus at 27°C (0.165). Lower values were obtained on the same prey at 20°C (0.089) or on C. vitis (0.030). The feeding habits of T. talbii may explain why the species coexists with the generalist Amblyseius aberrans or Typhlodromus pyri.
Decrease in tolerance to fenvalerate, in resistant Helicoverpa armigera after pupal diapause
Authors: Daly J. C. , Fisk J. H. 
Published: April 2011

AbstractPyrethroid resistant and susceptible adults of Helicoverpa armigera (Lepidoptera: Noctuidae) were screened for tolerance to pyrethroids after 6 wk or 12 wk pupal diapuse. Resistant larvae and F2 larvae from a cross between resistant and susceptible parents (two replicates), were reared under conditions to induce pupal diapause. After eclosion, adults were tested in glass vials coated with the pyrethroid fenvalerate, at a dose (DD) that is known to discriminate between susceptible and heterozygous resistant individuals. In all diapause experiments, the frequency of resistance was lower in the test groups that had experienced diapause compared with the non‐diapausing control group. The underlying cause of the decline is not certain but selective mortality of resistant versus susceptible individuals could not account for all the difference in two of the three experiments ‐ tolerance to the pyrethroid, fenvalerate, is most likely to have declined either as a consequence of diapause or from the extended time of development associated with diapause. These results indicate that monitoring programs could underestimate pyrethroid resistance frequencies when using H. armigera adults emerging from diapause.
Factors affecting entomopathogenic nematode infection of Plutella xylostella on a leaf surface
Authors: Baur M. E. , Kaya H. K. , Thurston G. S. 
Published: April 2011

AbstractWe investigated the ability of entomopathogenic nematodes to infect diamondback moth (DBM), Plutella xylostella (L.) (Lepidoptera: Plutellidae) on a leaf surface. In a leaf disk assay, mortality of late stage DBM larvae ranged from <7% caused by Steinernema kushidai Mamiya to >95% caused by S. carpocapsae (Weiser) All strain. LC50 values for S. carpocapsae, S. riobravis Cabanillas, Poinar & Raulston, and Heterorhabditis bacteriophora Poinar NC1 strain were 14.6, 15.4, and 65.4 nematodes/larva, respectively. S. carpocapsae, S. riobravis, and H. bacteriophora caused 29%, 33%, and 14% mortality of DBM pupae, respectively. DBM mortality caused by S. carpocapsae on radish declined at low (<76%) to moderate (76–90%) RH, because nematode survival and infectivity declined at low (76%) to moderate (76–90%) RH. However, DBM mortality caused by S. riobravis did not decline with RH. S. riobravis survival declined with RH, but infectivity did not. Overall, nematode survival and infectivity to DBM larvae were lower for S. riobravis than for S. carpocapsae. In addition, DBM mortality was higher on radish plants (pubescent leaves) than on cabbage plants (glaborous leaves).
Antibiosis and antixenosis of chrysanthemum cultivars to the aphid Aphis gossypii
Authors: Storer J. R. , van Emden H. F. 
Published: April 2011

AbstractAn assessment was made of the antibiotic and antixenotic resistance of three cultivars of autumn flowering chrysanthemum (derived from Dendranthema morifolium (Ramat) Tzvelev and D. indicum (L.) Desmoulins) to the aphid Aphis gossypii Glover. Antibiosis was also assessed at the top, middle and lower leaves of the plant. The three cultivars showed a range of resistance with Hero being the most susceptible, Surfine the most resistant and Purple Anne intermediate. There was a trend for antibiosis to improve with position down the plant, however there were cultivar by position interactions. Antixenosis was assessed at two levels, the first being under conditions where the aphid had complete access to the plant in caged choice assays and the second being under conditions where the aphid only had host odour to assess under olfactometer choice conditions. Preferences under the caged choice conditions found Hero to be the most preferred cultivar while there was no preference shown between Purple Anne and Surfine. However, olfactometer assessments showed Hero to be the least preferred of the three cultivars and, again, no preferences could be found between Purple Anne and Surfine.
The effects of different components of an artificial food on adult green lacewing (Chrysoperla carnea) fecundity and longevity
Authors: McEwen P. K. , Kidd N. A. C. 
Published: April 2011

AbstractArtificial foods comprising yeast products, sugar and water are often sprayed in the field to increase numbers of naturally occurring lacewing populations. The relative importance of the components of these foods for green lacewing (Chrysoperla carnea Stephens) fecundity and longevity is investigated in this paper. In laboratory experiments insects receiving only sugar solution lived significantly longer than those receiving diets containing both sugar and yeast (P<0.05). The inclusion of yeast is required for egg production, but few eggs are produced on yeast solution alone. For maximum egg production, food containing yeast and sugar must be offered on more than one occasion. Compared with insects given a diet comprising yeast autolysate, sugar, and water in the ratios 4:7:10, small but significant reductions in egg production rate were noted when the amount of either the yeast, or both the yeast and the sugar, was halved. The implication of these findings for the field is that viscous foods must be offered on a regular basis for maximum effectivity.
THE SUBWORD REVERSING METHOD
Authors: DEHORNOY PATRICK 
Published: April 2011

We summarize the main known results involving subword reversing, a method of semigroup theory for constructing van Kampen diagrams by referring to a preferred direction. In good cases, the method provides a powerful tool for investigating presented (semi)groups. In particular, it leads to cancellativity and embeddability criteria for monoids and to efficient solutions for the word problem of monoids and groups of fractions. The text includes some new results about mixed reversing (combination of left- and right-reversings) and about the combinatorial distance of braids.
Excellent Prognosis in a Subset of Patients with Ewing Sarcoma Identified at Diagnosis by CD56 Using Flow Cytometry
Authors: Ash Shifra , Luria Drorit , Cohen Ian J. , Goshen Yacov , Toledano Helen , Issakov Josephine , Yaniv Isaac , Avigad Smadar 
Published: April 2011

AbstractPurpose: Ewing sarcoma (ES) is considered a systemic disease with the majority of patients harboring micrometastases at diagnosis. Multiparameter flow cytometry (MPFC) was used to detect ES cells in bone marrow (BM) of ES patients at diagnosis and to evaluate the prognostic significance of CD56 expression in BM samples.Experimental Design: BM samples from 46 ES patients, 6 tumor aspirates, 2 ES cell lines, and 10 control BM samples were analyzed by MPFC. ES cells were identified by the combination of CD45−/CD90+/CD99+. CD56 was evaluated on these cells by a cutoff of 22%.Results: BM samples obtained from all patients at diagnosis were found to be positive for micrometastatic tumor cells assessed by CD99+/CD90+/CD45− expression. A total of 60% of the BM samples harbored high CD56 expression. There was a highly significant correlation between CD56 expression and progression-free survival (PFS; 69% in low/negative expression versus 30% in high expression groups, P = 0.024). In patients with localized nonpelvic disease, those expressing low/negative CD56 had 100% PFS versus 40% in the high expressing group (P = 0.02). By Cox regression analysis, CD56 was found to be an independent prognostic marker with an 11-fold increased risk for relapse in patients with localized disease (P = 0.006).Conclusion: All samples contained cells that are positive for the CD99+/CD90+/CD45− combination at diagnosis, indicating that ES is a systemic disease. CD56 expression could be used to reveal ES patients with excellent prognosis or patients predisposed to relapse, thus improving treatment stratification and implementation of personalized therapy. Clin Cancer Res; 17(9); 2900–7. ©2011 AACR.
Endocytosis of Resveratrol via Lipid Rafts and Activation of Downstream Signaling Pathways in Cancer Cells
Authors: Colin Didier , Limagne Emeric , Jeanningros Sylvie , Jacquel Arnaud , Lizard Gérard , Athias Anne , Gambert Philippe , Hichami Aziz , Latruffe Norbert , Solary Eric , Delmas Dominique 
Published: April 2011

Abstracttrans-Resveratrol has been proposed to prevent tumor growth and to sensitize cancer cells to anticancer agents. Polyphenol entry into the cells has remained poorly understood. Here, we show that [3H]-resveratrol enters colon cancer cells (SW480, SW620, HT29) and leukemia U937 cells through a monensin (5–20 μmol/L) -sensitive process that suggests clathrin-independent endocytosis. Uptake of the molecule can be prevented by methyl-β-cyclodextrin (2–12 mg/mL), nystatin (12 ng/mL), and filipin (1 μg/mL), which all disrupt plasma membrane lipid rafts. Accordingly, radiolabeled resveratrol accumulates in sphingomyelin- and cholesterol-enriched cell fractions. Interestingly, extracellular signal–regulated kinases (ERK), c-Jun NH2-terminal kinases (JNK), and Akt also accumulate in lipid rafts on resveratrol exposure (IC50 at 48 h ≈ 30 μmol/L in SW480 and U937 cells). In these rafts also, resveratrol promotes the recruitment, by the integrin αVβ3 (revealed by coimmunoprecipitation with an anti-integrin αVβ3 antibody), of signaling molecules that include the FAK (focal adhesion kinase), Fyn, Grb2, Ras, and SOS proteins. Resveratrol-induced activation of downstream signaling pathways and caspase-dependent apoptosis is prevented by endocytosis inhibitors, lipid raft–disrupting molecules, and the integrin antagonist peptide arginine-glycine-aspartate (500 nmol/L). Altogether, these data show the role played by lipid rafts in resveratrol endocytosis and activation of downstream pathways leading to cell death. Cancer Prev Res; 4(7); 1095–106. ©2011 AACR.
Dynamic and Thermodynamic Air–Sea Coupling Associated with the Indian Ocean Dipole Diagnosed from 23 WCRP CMIP3 Models*
Authors: Liu Lin , Yu Weidong , Li Tim 
Published: April 2011

Abstract
The performance of 23 World Climate Research Programme (WCRP) Coupled Model Intercomparison Project, phase 3 (CMIP3) models in the simulation of the Indian Ocean dipole (IOD) is evaluated, and the results show large diversity in the simulated IOD intensity. A detailed diagnosis is carried out to understand the role of the Bjerknes dynamic air–sea feedback and the thermodynamic air–sea coupling in shaping the different model behaviors. The Bjerknes feedback processes include the equatorial zonal wind response to SST, the thermocline response to the equatorial zonal wind, and the ocean subsurface temperature response to the thermocline variation. The thermodynamic feedback examined includes the wind–evaporation–SST and cloud–radiation–SST feedbacks. A combined Bjerknes and thermodynamic feedback intensity index is introduced. This index well reflects the simulated IOD strength contrast among the strong, moderate, and weak model groups. It gives a quantitative measure of the relative contribution of the dynamic and thermodynamic feedback processes.
The distinctive features in the dynamic and thermodynamic coupling strength are closely related to the mean state difference in the coupled models. A shallower (deeper) equatorial mean thermocline, a stronger (weaker) background vertical temperature gradient, and a greater (smaller) mean vertical upwelling velocity are found in the strong (weak) IOD simulation group. Thus, the mean state biases greatly affect the air–sea coupling strength on the interannual time scale. A number of models failed to simulate the observed positive wind–evaporation–SST feedback during the IOD developing phase. Analysis indicates that the bias arises from a greater contribution to the surface latent heat flux anomaly by the sea–air specific humidity difference than by the wind speed anomaly.
Prediction of the Tensile Load Capability of Co-Cured Steel-Composite Tubular Single Lap Joints Considering Thermal Degradation
Authors: Lee Dai Gil , Cho Durk Hyun 
Published: April 2011

Co-cured joints composed of composite and steel structures are realized by the excess resin extracted during cure of composite prepreg and the coupling pressure due to residual thermal stresses generated by the difference of coefficients of thermal expansion between the two materials. Although the excess resin from the composite prepreg is less dependent on the environmental temperature compared to conventional epoxy adhesives in which rubber is added to strengthen toughness, the coupling pressure is much dependent on the environmental temperature. In this study, the tensile load capability of co-cured joints composed of carbon fiber epoxy composite and steel adherends was experimentally investigated with respect to the stacking sequence of the composite and the environmental temperature. Also, the stress distributions in the composite were calculated by finite element method, from which the failure index of the composite adherend was calculated considering thermal degradation of the composite. The co-cured steel-composite tubular single lap joint under tensile loads might be applied to hybrid structures such as golf clubs and automotive composite propeller shafts which have a conventional adhesively-bonded joint by epoxy adhesives with fillers between a carbon/epoxy shaft and a metal shaft.
Testing and Analysis of Composite Skin/Stringer Debonding under Multi-Axial Loading
Authors: Krueger Ronald , Cvitkovich Michael K. , O'Brien T. Kevin , Minguet Pierre J. 
Published: April 2011

A consistent step-wise approach is presented to investigate the damage mechanism in composite bonded skin/stringer constructions under uniaxial and biaxial (in-plane/out-of-plane) loading conditions. The approach uses experiments to detect the failure mechanism, computational stress analysis to determine the location of first matrix cracking and computational fracture mechanics to investigate the potential for delamination growth. In a first step, tests were performed on specimens, which consisted of a tapered composite flange, representing a stringer or frame, bonded onto a composite skin. Tests were performed under monotonic loading conditions in tension, three-point bending, and combined tension/bending to evaluate the debonding mechanisms between the skin and the bonded stringer. For combined tension/bending testing, a unique servohydraulic load frame was used that was capable of applying both in-plane tension and out-of-plane bending loads simultaneously. Specimen edges were examined on the microscope to document the damage occurrence and to identify typical damage patterns. For all three load cases, observed failure initiated in the flange, near the flange tip, causing the flange to almost fully debond from skin. In a second step, a two dimensional plane-strain finite element model was developed to analyze the different test cases using a geometrically nonlinear solution. For all three loading conditions, computed principal stresses exceeded the transverse strength of the material in those areas of the flange where the matrix cracks had developed during the tests. In a third step, delaminations of various lengths were simulated in two locations where delaminations were observed during the tests. The analyses showed that at the loads corresponding to matrix ply crack initiation computed strain energy release rates exceeded the values obtained from a mixed mode failure criterion in one location. Hence, unstable delamination propagation is likely to occur as observed in the experiments.
Non-Fickian Moisture Diffusion in Polymeric Composites
Authors: Cai L. -W. , Weitsman Y. 
Published: April 2011

This article concerns the effects of non-Fickian water diffusion in fiber-reinforced polymeric composites. The departure from classical diffusion is attributed to the time-dependent response of the polymer, akin to viscoelastic mechanical response. The purpose of the present work is to propose a methodology to reduce non-Fickian moisture weight gain data in a manner which enables the evaluation of the diffusion coefficient and moisture profiles across the thickness of composite laminates. The evaluation of those moisture profiles is essential to the computation of residual stresses within composite laminates. It is demonstrated that in some circumstances the non-Fickian moisture profiles result in residual hygro-thermal stresses which differ by about 25% from predictions based upon classical diffusion.