bluuebunny/crossref_metadata_2025_split huggingface dataset:
Abdominal gland secretion of Bledius rove beetles as an effective defence against predators
Authors: Steidle Johannes L. M. , Dettner Konrad 
Published: April 2011

AbstractThe biological function of the abdominal gland of the rove beetle genus Bledius (Coleoptera: Staphylinidae: Oxytelinae) was examined using behavioural criteria. The attractant effect of the abdominal secretion on the Bledius predators Dyschirius obscurus and D. thoracicus (Carabidae), described in the literature, was identified as artificial. In choice experiments the secretion showed repellent effects on natural predators of Bledius furcatus, B. spectabilis and B. arenarius. In predator‐prey encounters with Cataglyphis bicolor (Formicidae) and Labidura riparia (Dermaptera) the gland secretion of B. furcatus induced cleaning behaviour. When attacked by C. bicolor the chance of survival for B. furcatus was increased by the presence of the abdominal gland secretion. This clearly shows that the abdominal gland of the genus Bledius is used for defensive purposes.
Cleome monophylla essential oil and its constituents as tick (Rhipicephalus appendiculatus) and maize weevil (Sitophilus zeamais) repellents
Authors: Ndungu Mary , Lwande Wilber , Hassanali Ahmed , Moreka Lambert , Chhabra Sumesh Chander 
Published: April 2011

AbstractThe repellency of the essential oil of the shrub Cleome monophylla (Family: Capparidaceae) and identified constituents of the oil were evaluated against the livestock tick, Rhipicephalus appendiculatus and the maize weevil, Sitophillus zeamais. In a tick climbing repellency bioassay, the oil of C. monophylla exhibited repellency which, at the highest dose, was comparable to that of the commercial arthropod repellent N, N‐diethyl toluamide (DEET). In a Y‐tube olfactometer bioassay, C. monophylla oil showed higher or comparable repellency against S. zeamais relative to DEET at all the doses tested. 14 Compounds were identified in the C. monophylla oil by GC, GC‐MS and coinjection with authentic samples. Terpenolene was found to occur in largest quantity (14%) followed by 1‐α‐terpeneol (10%), pentacosane (9%), (α + β)‐humulene (8%), phytol (5%) and 2‐dodecanone (4%). The most repellent components against R. appendiculatus and S. zeamais were 1‐α‐terpeneol and 2‐dodecanone. The overall pattern of repellency activity of the C. monophylla constituents with respect to the two arthropods was, however, different. The potential of C. monophylla in tick and maize weevil control is discussed.
Pea leaf weevil herbivory on pea seedlings: effects on growth response and yield
Authors: Williams Livy , Schotzko D. J. , O'Keeffe L. E. 
Published: April 2011

AbstractField experiments were conducted to determine growth and yield responses of Pisum sativum L. to defoliation by adult Sitona lineatus (L.). Seedlings grown under conventional (moldboard plowed) and conservation (chisel plowed) tillage treatments were infested for a 1‐week period with 0, 1 and 8 weevils per plant at two times: at 75% field emergence and 1 week later. After the early infestation, defoliation for the control, low and high weevil densities was about 0, 15 and 50%, respectively, while defoliation after the late infestation was about 0, 10 and 35%. An undercompensatory growth response was observed in one experiment after seedlings were subjected to moderate levels of early defoliation. Exact compensation was observed in two experiments after early infestations of low and high Sitona densities. Sitona defoliation reduced the number of pods per plant and pod length in two experiments. However, seed biomass was never significantly reduced. Averaged over all experiments, reduction in seed biomass due to high Sitona densities was 10 and 5% for early and late infestations, respectively. Tillage treatments did not affect Pisum compensatory growth response, although yield components were sometimes greater in conservation tillage than in conventional tillage, possibly due to slightly greater soil moisture in the conservation tillage plots.
Plant oils as grain protectants against infestations of Cryptolestes pusillus and Rhyzopertha dominica in stored grain
Authors: Obeng‐Ofori D. 
Published: April 2011

AbstractPlant oils (cottonseed, soybean, corn, groundnut and palm) at different dosages were evaluated in the laboratory for their ability to suppress the populations of Cryptolestes pusillus and Rhyzopertha dominica in maize and sorghum. Exposure of adults of both beetle species to grains treated with 10 ml/kg of the different oils induced 100% mortality within 24 h. A dose of 5 ml/kg of each oil significantly decreased the progeny produced by R. dominica. Complete protection was achieved on grains treated with 10 ml/kg. These oils also repelled the adults of both species. Percentage weight loss caused by R. dominica in grains treated with 5 ml/kg and 10 ml/kg levels were significantly lower than in untreated grains. Oil treatment did not affect the germination of, or water absorption by, maize and sorghum grains compared with untreated grains. The potential use of plant oils in the management of insect pests in traditional grain storage is discussed.
Toxicity of Bacillus thuringiensisδ‐ endotoxins toward the potato aphid in an artificial diet bioassay
Authors: Walters Frederick S. , English Leigh H. 
Published: April 2011

AbstractRecent investigations indicated that Bacillus thuringiensis delta‐endotoxins (DET) possess aphidicidal activity in an artificial diet bioassay. Crystalline preparations of CryIIA, CryIIIA and CryIVD solubilized in a slightly alkaline sucrose/amino acid diet clearly imparted toxicity toward adults of potato aphid, Macrosiphum euphorbiae (Thomas) (Homoptera: Aphididae) after 4–5 days of continuous feeding. No obvious feeding deterrence was noted in these assays, as copious honeydew was produced and aphids often died in a feeding position. CryIIIA which was solubilized in aphid diet, but filtered to remove spores or crystalline toxin lacked aphidicidal activity. Spores from an acrystalliferous strain (EG2205) were not toxic by themselves at 7.75 × 105 spores/ml aphid diet, but did restore toxicity to the filtered CryIIIA solution. Therefore, low levels of spores may be very effective in concert with DET for aphicidal activity. Results also clearly demonstrated that a suspension of crystalline CryIIIA alone, without spores, exhibited toxicity. Therefore, DET may be more toxic to the aphids when imbibed as a fine suspension, perhaps indicating the need for slow solubilization into the aphid midgut.
Genetic variation in chrysanthemum for resistance to Frankliniella occidentalis
Authors: de Jager C. M. , Butôt R. P. T. , Klinkhamer P. G. L. , de Jong T. J. , Wolff K. , van der Meijden E. 
Published: April 2011

AbstractIn a choice‐experiment, 42 chrysanthemum cultivars were screened for resistance to Frankliniella occidentalis (Pergande). Oviposition preference, two types of feeding damage and thrips numbers per flower were recorded as measures of resistance. A large genetic variation in thrips resistance was found among the cultivars screened. The amount of feeding damage was strongly determined by oviposition preference. Besides, a positive correlation was found between the oviposition preference in non‐flowering chrysanthemums (number of eggs) and flowering chrysanthemums (number of thrips per flower). Thrips feeding on young, developing tissues, causes growth damage because affected cells are unable to expand and leaves become distorted. Thrips feeding on older, expanded leaves causes cells to become filled with air, resulting in ‘silver’ damage. The amounts of growth‐ and ‘silver’ damage were negatively correlated suggesting that thrips chose either young or older leaves to feed on. The order of resistance among cultivars did not change during the experiment. In order to get more insight in resistance mechanisms the influence of some plant‐ and flower characters on resistance was examined. The plant characters height, number of leaves, flower production and flower weight were all negatively correlated with resistance. It is suggested that tall chrysanthemum cultivars with many and large flowers may invest less in defence than smaller cultivars, and therefore are more damaged by thrips.
Junctional adhesion molecules are required for melanoma cell lines transendothelial migration in vitro
Authors: Ghislin Stephanie , Obino Dorian , Middendorp Sandrine , Boggetto Nicole , Alcaide‐Loridan Catherine , Deshayes Frederique 
Published: April 2011

SummaryOne of the main steps of metastasis is extravasation, a phenomenon well described in lymphocytes but remaining to be fully uncovered for melanoma. Junctional adhesion molecules (JAMs) control the transendothelial migration of leukocytes. To date, the role of the JAM proteins, notably JAM‐A and JAM‐C, has not been examined in melanoma. Here, we compared two melanoma tumor cell lines, A375 and SLM8 cells, the A375 cell line being four times more efficient than the SLM8 cells in the crossing of the endothelial monolayer. We show evidence of the differential expression of JAM‐A and JAM‐C in these cell lines with JAM‐C mainly expressed in the A375 cell line, and JAM‐A detected preferentially in the SLM8 cells. To further dissect the respective roles of these proteins, we used both siRNA and blocking antibodies to decrease JAM‐A and JAM‐C expression.
Directed Culturing of Microorganisms Using Metatranscriptomics
Authors: Bomar Lindsey , Maltz Michele , Colston Sophie , Graf Joerg 
Published: April 2011

ABSTRACT

The vast majority of bacterial species remain uncultured, and this severely limits the investigation of their physiology, metabolic capabilities, and role in the environment. High-throughput sequencing of RNA transcripts (RNA-seq) allows the investigation of the diverse physiologies from uncultured microorganisms in their natural habitat. Here, we report the use of RNA-seq for characterizing the metatranscriptome of the simple gut microbiome from the medicinal leech
Hirudo verbana
and for utilizing this information to design a medium for cultivating members of the microbiome. Expression data suggested that a
Rikenella
-like bacterium, the most abundant but uncultured symbiont, forages on sulfated- and sialated-mucin glycans that are fermented, leading to the secretion of acetate. Histological stains were consistent with the presence of sulfated and sialated mucins along the crop epithelium. The second dominant symbiont,
Aeromonas veronii
, grows in two different microenvironments and is predicted to utilize either acetate or carbohydrates. Based on the metatranscriptome, a medium containing mucin was designed, which enabled the cultivation of the
Rikenella
-like bacterium. Metatranscriptomes shed light on microbial metabolism
in situ
and provide critical clues for directing the culturing of uncultured microorganisms. By choosing a condition under which the desired organism is rapidly proliferating and focusing on highly expressed genes encoding hydrolytic enzymes, binding proteins, and transporters, one can identify an organism’s nutritional preferences and design a culture medium.

IMPORTANCE
The number of prokaryotes on the planet has been estimated to exceed 10
30
cells, and the overwhelming majority of them have evaded cultivation, making it difficult to investigate their ecological, medical, and industrial relevance. The application of transcriptomics based on high-throughput sequencing of RNA transcripts (RNA-seq) to microorganisms in their natural environment can provide investigators with insight into their physiologies under optimal growth conditions. We utilized RNA-seq to learn more about the uncultured and cultured symbionts that comprise the relatively simple digestive-tract microbiome of the medicinal leech. The expression data revealed highly expressed hydrolytic enzymes and transporters that provided critical clues for the design of a culture medium enabling the isolation of the previously uncultured
Rikenella
-like symbiont. This directed culturing method will greatly aid efforts aimed at understanding uncultured microorganisms, including beneficial symbionts, pathogens, and ecologically relevant microorganisms, by facilitating genome sequencing, physiological characterization, and genetic manipulation of the previously uncultured microbes.
Sensitivity of ENSO to Stratification in a Recharge–Discharge Conceptual Model
Authors: Thual Sulian , Dewitte Boris , An Soon-Il , Ayoub Nadia 
Published: April 2011

Abstract
El Niño–Southern Oscillation (ENSO) is driven by large-scale ocean–atmosphere interactions in the equatorial Pacific and is sensitive to change in the mean state. Whereas conceptual models of ENSO usually consider the depth of the thermocline to be influential on the stability of ENSO, the observed changes in the depth of the 20°C isotherm are rather weak, on the order of approximately 5 m over the last decades. Conversely, change in stratification that affects both the intensity and sharpness of the thermocline can be pronounced. Here, the two-strip conceptual model of An and Jin is extended to include three parameters (i.e., the contribution of the first three baroclinic modes) that account for the main characteristics of the mean thermocline vertical structure.
A stability analysis of the model is carried out that indicates that the model sustains a lower ENSO mode when the high-order baroclinic modes (M2 and M3) are considered. The sensitivity of the model solution to the coupling efficiency further indicates that, in the weak coupling regime, the model allows for several ocean basin modes at low frequency. The latter can eventually merge into a low-frequency and unstable mode representative of ENSO as the coupling efficiency increases. Also, higher baroclinic modes project more energy onto the ocean dynamics for the same input of wind forcing. Therefore, in this study’s model, a shallower, yet more intense mean thermocline may still sustain a strong (i.e., unstable) and low-frequency ENSO mode. Sensitivity tests to the strength of the two dominant feedbacks (thermocline vs zonal advection) indicate that the presence of high-order baroclinic modes favors the bifurcation from a low-frequency regime to a higher-frequency regime when the zonal advective feedback is enhanced.
It is suggested that the proposed formalism can be used to interpret and measure the sensitivity of coupled general circulation models to climate change.
Fatigue Notch Sensitivity of Glass Woven Fabric Composites Having a Circular Hole under Tension/Torsion Biaxial Loading
Authors: Fujii Toru , Shiina Toru , Okubo Kazuya 
Published: April 2011

Fatigue notch sensitivity of woven fabric composites having a circular hole under tension/torsion biaxial loading was investigated. In-phase (proportional) biaxial stress was applied to tubular specimens. A fatigue notch factor was used to evaluate the fatigue notch sensitivity. The experimental results revealed that the fatigue notch factor was approximately linear with respect to a parameter; cos (tan-' ce) for any fatigue life (a is biaxiality ratio of combined stress). The fatigue notch factor decreased with an increase in fatigue life in the case where the shear stress component was relatively small. However, in the case where the shear stress component was large, it increased with an increase in fatigue life. Under pure torsion loading, fatigue damage did not progress along the principal axis. It grew along both longitudinal and transverse fiber bundles. An empirical equation which can easily predict the fatigue notch factor at any arbitrary fatigue life under biaxial loading was proposed. Unknown variables in this equation are determined by fatigue tests under uniaxial tensile and pure torsion loadings.
A Numerical and Experimental Study of Delaminated Layered Composites
Authors: Mukherjee Yu Xie , Gulrajani Sunil N. , Mukherjee Subrata , Netravali Anil N. 
Published: April 2011

This paper describes the development of a finite element-based computer model for the determination of stress fields and energy release rates around a delamination in a layered composite. The model is fully three-dimensional. Each layer of a composite material is modelled as homogeneous and orthotropic. The basic finite elements are isoparametric 20-noded bricks with collapsed, prismatic quarter-point elements around the delamination front. Contact theory is used to prevent interpenetration between the faces of a delamination. The modified crack closure method is used to calculate the energy release rates around a delamination. Preliminary experiments are performed to study the growth of a delamination between the layers of a two-layer laminate-one epoxy and the other graphite/epoxy. Initial results from the experiments and numerical simulations are shown to be consistent.
A Modified Procedure to Measure Bending Strength and Modulus of Advanced Composites by Means of Compression Bending
Authors: Fukuda H. , Katoh H. , Uesugi H. 
Published: April 2011

This paper deals with a new bending test method for advanced composites. Although the conventional three and four-point bending tests are convenient to obtain bending modulus and strength, composites may fail at the loading nose due to the stress concentration, because composite materials have high anisotropy and they fail in a brittle manner. To compensate for the above shortcoming, we developed a new bending test method which is based on a buckling of a column. Both strength and modulus could be measured. In the present paper, another refined methodology to evaluate the bending modulus is discussed in addition to the bending strength. 1300 and T800 carbon/epoxy unidirectional and quasi-isotropic laminates with various specimen lengths were tested. The superiority of the present method was demonstrated especially for evaluating the strength.
Analytical Models for Low Cost Manufacturing of Composite Components by Filament Winding, Part I: Direct Kinematics
Authors: Mazumdar S. K. , Hoa S. V. 
Published: April 2011

Filament winding technique is not used to its overall capacity because of insufficient understanding of the kinematics of filament winding. In order to effectively utilize the capability of filament winding technique, a Geometric Approach based on the algebraic and trigonometric relations is presented to determine the machine motions for generating desired fiber distribution on axisymmetric, non-axisymmetric, cylindrical, and non-cylindrical mandrel shapes. Analytical models thus developed are found to be extremely useful tools for laying down the fiber on predetermined path in lieu of costly techniques such as teach-in-programming, simulation, CAD/CAM, etc. It is suggested that a sophisticated filament winding machine is not always necessary to fabricate a complex structure. A filament winding machine with two and three degrees of freedom can perform the same task on various types of mandrel surface with fewer driven parts, higher accuracy, and lower manufacturing cost. Present method determines the machine motion in a few seconds and provides exact solution in generating the desired fiber winding angle on certain types of mandrel surface which has polygonal cross-sections. Based on the Geometric Approach, a user friendly computer program "DIRECTIKIN" is developed to study the direct kinematics of filament winding. Using the program "DIRECIXIN, effects of location of the delivery point, fiber winding angle distribution, and mandrel shape geometry on winding motions are discussed. Experimental verification of the model is performed on a McClean Anderson filament winding machine for cylindrical and non-cylindrical mandrels.
Three-Dimensional Failure Analysis of Plain Weave Textile Composites Using a Global/Local Finite Element Method
Authors: Woo Kyeongsik , Whitcomb John D. 
Published: April 2011

Textile composites are known to have improved out-of-plane properties and impact resistance. However, detailed analysis of textile composites is very difficult to perform due to the geometric complexity. In the present study, a practical computational procedure based on a global/local finite element method was developed for detailed analysis of textile composites. This procedure utilizes two problem levels: global and local levels. At the global level, an initial global solution was obtained using a coarse global mesh. At the local level, a small portion of the textile composite was modeled with a refined local mesh. For the global analysis, macroelements were used since the use of effective engineering properties are not in general accurate for the larger microstructural scale found in textile composites. Results indicated that the failure behavior of plain weave textile composites was sensitive to the fiber bundle waviness. The initial failure mode was the fiber bundle separation when the waviness ratio was large while it was the fiber bundle fracture when the waviness ratio was small. It was also found that the stress distributions near the free surface were different from those inside. The stress level was much higher inside than near the free surface. However, the boundary region was shallow and was limited to the outer-most layer.
Measurement of the Degree of Cure of Carbon Fiber Epoxy Composite Materials
Authors: Kim Jin Soo , Lee Dai Gil 
Published: April 2011

In this study, a dielectric cure monitoring system which consists of an electric circuit, a sensor and a personal computer was developed to on-line monitor the dielectric properties of carbon fiber epoxy composite materials. Also, the kinetic model of carbon fiber epoxy composite materials was developed by curve fitting of the differential scanning calorimetry (DSC) data. The start and end points of cure and the relationship between the dissipation factor and the degree of cure were obtained by comparing the dissipation factor from the dielectric properties with the degree of cure from the DSC data. The relationship between the dissipation factor and the degree of cure was tested under various temperature profiles.
Impact Testing on Composites Laminates and Sandwich Panels
Authors: Scarponi Claudio , Briotti Giuseppe , Barboni Renato , Marcone Antonio , Iannone Michele 
Published: April 2011

The purpose of this work was the evaluation of the behavior of fiber-reinforced composites and sandwich panels for aeronautical applications under impact. Experimental tests were performed on several specimen configurations, based on different quasi-isotropic lay-up and materials such CFRP, CFRTP and a syntactic foam as the core of sandwich panels. Considering the high specific mechanics characteristics of such a foam and its cocurability with the facesheet material, symmetric and non-symmetric sandwich configurations have been tested. The study has pointed out the advantages for aeronautic constructions of different materials and the influence of the core position along the panel thickness. The impact tests were performed with a falling weight machine, which allowed the most important dynamic and kinetic parameters, such as the contact force, impactor velocity and displacement and perforation energy to be measured. Delamination areas of each specimen were also measured using N.D.I. reflection ultrasonic techniques. In order to determine the residual strength, Compression After Impact tests were performed on specimens that have an indentation of approximately 0.3-0.4 mm. A numerical simulation was performed using a transient dynamic Finite Element Analysis. The main goal of this analysis was to define the controlling factors for high velocity impact simulation, such as the increase of geometric non-linearity and the delamination effects. Moreover, the delamination areas and positions were determined taking in account the different boundary conditions. The study have pointed out the behavior of thermoset, thermoplastic and unsymmetric sandwich panels.