Flexible Wing Kinematics of a Free-Flying Beetle (Rhinoceros Beetle Trypoxylus Dichotomus)

Detailed 3-Dimensional (3D) wing kinematics was experimentally presented in free flight of a beetle,Trypoxylus dichotomus,which has a pair of elytra (forewings) and flexible hind wings.The kinematic parameters such as the wing tip trajectory,angle of attack and camber deformation were obtained from a 3D reconstruction technique that involves the use of two synchronized high-speed cameras to digitize various points marked on the wings.Our data showed outstanding characteristics of deformation and flexibility of the beetle's hind wing compared with other measured insects,especially in the chordwise and spanwise directions during flapping motion.The hind wing produced 16％ maximum positive camber deformation during the downstroke.It also experienced twisted shape showing large variation of the angle of attack from the root to the tip during the upstroke.     

Measuring the Three-Dimensional Kinematics of a Free-Swimming Koi Carp by Video Tracking Method

A video tracking system for measuring three-dimensional kinematics of a free-swimming fish is presented. The tracking is accomplished by simultaneously taking images from the ventral view and the lateral view of the fish with two cameras mounted on two computer-controlled and mutually orthogonal translation stages. Compared to the previous system we reported, the time resolution is greatly improved. A koi carp is selected for the experiment. By processing the images caught by the video tracking system, the three-dimensional kinematics of the koi carp during a continuous swimming containing several moderate maneuvers are obtained. In particular, the pitching motion of fish body and the tail motion, including lateral excursion, variation in tail height and torsion, are revealed for burst-and-coast swimming and turning maneuver. The error analysis is also provided for the measurement results.     

Identification of Virulent Isolates of the Entomopathogenic Fungus Nomuraea Rileyi (F) Samson for the Management of Helicoverpa Armigera and Spodoptera Litura

Eleven geographical isolates of the entomopathogenic fungus Nomuraea rileyi (Farlow) Samson of Helicoverpa armigera (Hubner)/Spodoptera litura (Fabricius) origin were studied for efficacy against the two host insects. Laboratory bioassays at a concentration of 2 x 10(8) conidia ml(-1) indicated that N. rileyi isolates of S. litura origin were better in terms of time taken for mycosis and mortality in both the test larvae: S. litura (77-80% mortality in 7 days) and H. armigera (79-85% in 8 days). Among the isolates of S. litura origin, geographical isolates from Hyderabad and Karimnagar were superior in terms of high percent kill as well as 100% germination of conidia within 48 h. Fastest germination was observed with Karimnagar isolate followed by Hyderabad isolate. Conidial yield was highest on barley-carrot extract-yeast extract medium. However in terms of material cost, barley-yeast extract medium was the lowest. The Karimnagar isolate of S. litura origin gave the highest conidial yield on barley-yeast extract medium. Chitinolytic enzyme profiles of different isolates revealed polymorphism in all the isolates from S. litura origin. Overall among the parameters studied the best traits were found in the Karimnagar isolate of S. litura origin.     

Automated Kinematics Measurement and Aerodynamics of a Bioinspired Flapping Rotary Wing

A physical model for a micro air vehicle with Flapping Rotary Wings (FRW) is investigated by measuring the wing kinematics in trim conditions and computing the corresponding aerodynamic force using computational fluid dynamics.In order to capture the motion image and reconstruct the positions and orientations of the wing,the photogrammetric method is adopted and a method for automated recognition of the marked points is developed.The characteristics of the realistic wing kinematics are presented.The results show that the non-dimensional rotating speed is a linear function of non-dimensional flapping frequency regardless of the initial angles of attack.Moreover,the effects of wing kinematics on aerodynamic force production and the underlying mechanism are analyzed.The results show that the wing passive pitching caused by elastic deformation can significantly enhance lift production.The Strouhal number of the FRW is much higher than that of general flapping wings,indicating the stronger unsteadiness of flows in FRW.     

Metamorphosis of Wing Motor System in the Silk Moth, Bombyx mori: Origin of Wing Motor Neurons

The origin of the peripheral nerve and motor neurons that innervate the adult mesothoracic dorsal longitudinal muscles (DLMs) was examined in the silk moth, Bombyx mori . The anatomical features of the peripheral nerve and motor neurons were investigated by dissection, electron microscopy, and cobalt back-fill staining at different pupal stages. These studies showed that the peripheral nerve (IIN1c) that innervates the adult DLMs originates from a branch (db branch) of the larval mesothoracic dorsal nerve that innervates the larval DLMs. During metamorphosis the larval nerve shortens or lengthens locally without change in its basic branching pattern, and the db branch moves towards the mesothoracic ganglion to become the IIN1c. All the adult DLM motor neurons are from larval ones. Nine of the 14 larval DLM motor neurons survive during metamorphosis to become adult DLM motor neurons, and 5 disappear in early pupal stages.     

Physiological Mechanisms of Pheromonostatic Responses: effects of Adrenergic Agonists and Antagonists on Moth (Helicoverpa armigera) Pheromone Biosynthesis

The adrenergic agonists octopamine, tyramine and clonidine inhibited the normal pheromonotropic action due to PBAN (pheromone biosynthesis activating neuropeptide) in incubations of intersegmental tissues that are situated between the 8th and 9th abdominal segments of the moth ovipositor tip. This inhibition was reversed in the presence of the adrenergic antagonists phentolamine, yohimbine and chlorpromazine. Incubations of 8th segments alone, which do not produce pheromone, resulted in elevated levels of intracellular cAMP in the presence of octopamine. The physiological significance of this phenomenon is unclear. However, clonidine (an alpha(2) selective agonist) did not duplicate octopamine stimulation of intracellular cAMP in 8th segment cultures. In intersegmental membrane cultures clonidine successfully duplicated the octopamine inhibition of both pheromone and intracellular cAMP production. The physiological significance of octopaminergic receptors mediating the inhibitory response of intersegments was investigated by experiments in vivo. When PBAN was injected into photophase females the normal pheromonotropic activity due to the injected PBAN dropped after 2h. In the presence of clonidine, normal peak stimulatory levels were never attained and a faster decline was observed. Clonidine also inhibited the pheromonotropic response of 24h-decapitated females to PBAN. Adrenergic antagonists successfully reversed the inhibitory effect of clonidine in decapitated females, but did not reverse the effect of clonidine in photophase females. In addition, when clonidine was injected into female moths during the scotophase normal peak pheromone titers were reduced although no effect on calling behavior was observed. Copyright 1997 Elsevier Science Ltd. All rights reserved     

Stereoselective Synthesis of (Z,Z)-3, 13-Octadecadienyl Acetate,the Attractant for Smaller Clear Wing Moth

(Z)-3-Hexene-1, 6-diol, a new synthon for the synthesis of (Z)-olefinic pheromones, was prepared from 1, 4-cyclohexadiene. This synthon was used in the synthesis of (Z, Z)-3, 13-octadecadienyl acetate, whose high stereochemical purity at C–3 was essential in attracting male Synanthedon tenuis Butler.     

Effective control of a field population of Helicoverpa armigera by using the small RNA virus Helicoverpa armigera stunt virus (Tetraviridae: Omegatetravirus)

The first comprehensive field trial using an insect small RNA virus as a control agent on a cropping system was conducted with the Helicoverpa armigera stunt virus (family Tetraviridae, genus Omegatetravirus, HaSV). The virus was semipurified, quantified, and applied at two rates, 4 x 10(15) and 4 x 10(14) virus particles/ha, with minimal formulation on sorghum against the bollworm Helicoverpa armigera (Hübner). For comparison, a commercial preparation of Helicoverpa zea single-nucleopolyhedrovirus (HzSNPV, Gemstar) was applied at the same time at 9.27 x 10(11) polyhedral inclusion bodies/ha. The HaSV application rates were determined by a novel procedure using laboratory LC50 bioassay data for HaSV and HzSNPV and calibration to the known field application rate of the HzSNPV. The baculovirus and the higher rate of HaSV produced statistically equivalent reductions in the larval populations of around 50% at both 3 and 6 d postapplication (dpa) compared with untreated plots. The 10-fold lower rate of HaSV reduced the larval population by 50% at 3 dpa and approximately 30% at 6 dpa. Persistence of HaSV over a 72-h period was found to be similar to that of HzSNPV, although the amount of HaSV available on the sorghum heads increased at 130 h postapplication, due most likely to dispersal of newly produced virus from cadavers and frass. The results from this trial indicate that HaSV could be used as an effective biopesticide for the control of H. armigera in sorghum and the ramifications for its broader use are discussed.     

Kinematics,Deformation,and Aerodynamics of a Flexible Flapping Rotary Wing in Hovering Flight

The Flapping Rotary Wing(FRW)is a micro air vehicle wing layout coupling flapping,pitching,and rotating motions.It can gain bencfits in high lift from a fast passive rotating motion,which is tightly related to the passive pitching motion directly caused by wing flexible deformation.Therefore,flexible deformation is crucial for the wing kinematics and aerodynamic performance of an FRW.In this paper,we explored the effct of flexibility on wing kinematics and acrodynamics on the basis of a mechanical FRW model.A photogrammetric method was adopted to capture motion images according to which wing orientations and deformations were reconstructed.Corresponding acrodynamic force was computed using computational fluid dynamic method,and wing kinematics and deformations were used as simulation inputs.The experimental measurements presented the real orientation and deformation pattem of a real FRW.The wing passive deformation of a high-intensity FRW was found to be mainly caused by inertial force,and a linear positive spanwise twist was observed in the FRW.The effects of wing deformation on aerodynamic force production and the underlying mechanism were addressed.Results showed that lift augment,rotating moment enhancement,and power efficiency improvement can be achieved when a wing becomes flexible.Wing spanwise twist mainly accounts for these changes in aerodynamics,and increment in spanwise twist could further contributes to aerodynamic improvement.     

Infection of its lepidopteran host by the Helicoverpa armigera stunt virus (Tetraviridae)

Techniques of microscopy and histopathology were employed to study the positive-sense, single-stranded RNA virus, the Helicoverpa armigera stunt virus (HaSV; omegatetravirus, Tetraviridae) infecting its caterpillar host. Infection of the virus per os during the first three instars of larval development is virulent and leads to rapid stunting and mortality. In contrast, no detectable symptoms occur in later larval development, signifying a high degree of developmental resistance. A quantitative study of cell populations in the host midgut during this time showed that increased cell numbers during development alone could not account for the increase in resistance. HaSV infection was restricted to the midgut and three of its four cell types. In younger larvae, the virus initiated its infection in closely situated foci that appeared to expand to link with others to cover larger areas of the midgut. The midgut cells of the infected larvae responded with an increased rate of sloughing to an extent rendering the midgut incapable of maintenance or recovery of normal function. In contrast, infection of older larvae by HaSV did not lead to overt pathology although foci of HaSV infection were detected in their midguts. However, the foci were more sparsely situated, failed to expand, and eventually disappeared, presumably due to cell sloughing. These observations indicate that cell sloughing is an immune response existing throughout larval development but midguts of older larvae have an additional mechanism to account for the increased resistance. This second mechanism results in midgut cells becoming more refractory to infection and, combined with cell sloughing, allows the midguts of older larvae to recover more readily from HaSV infection. These two mechanisms are similar to those seen with host responses to baculoviruses, which display developmental resistance to a lesser degree against more general infections. HaSV remaining in the midgut appears to amplify the degree of developmental resistance.     

Use of a Digital Image Correlation Technique for Measuring the Material Properties of Beetle Wing

Beetle wings are very specialized flight organs consisting of the veins and membranes.Therefore it is necessary from abionic view to investigate the material properties of a beetle wing experimentally.In the present study,we have used a DigitalImage Correlation (DIC) technique to measure the elastic modulus of a beetle wing membrane.Specimens were prepared bycarefully cutting a beetle hind wing into 3.0 mm by 7.0 mm segments (the gage length was 5 mm).We used a scanning electronmicroscope for a precise measurement of the thickness of the beetle wing membrane.The specimen was attached to a designedfixture to induce a uniform displacement by means of a micromanipulator.We used an ARAMISTM system based on the digitalimage correlation technique to measure the corresponding displacement of a specimen.The thickness of the beetle wing variedat different points of the membrane.The elastic modulus differed in relation to the membrane arrangement showing a structuralanisotropy;the elastic modulus in the chordwise direction is approximately 2.65 GPa,which is three times larger than the elasticmodulus in the spanwise direction of 0.84 GPa.As a result,the digital image correlation-based ARAMIS system was suc-cessfully used to measure the elastic modulus of a beetle wing.In addition to membrane’s elastic modulus,we considered thePoisson’s ratio of the membrane and measured the elastic modulus of a vein using an Instron universal tensile machine.Theresult reveals the Poisson’s ratio is nearly zero and the elastic modulus of a vein is about 11 GPa.     

Modeling the Cellular Mechanisms and Olfactory Input Underlying the Triphasic Response of Moth Pheromone-Sensitive Projection Neurons

In the antennal lobe of the noctuid moth Agrotis ipsilon, most pheromone-sensitive projection neurons (PNs) exhibit a triphasic firing pattern of excitation (E₁)-inhibition (I)-excitation (E₂) in response to a pulse of the sex pheromone. To understand the mechanisms underlying this stereotypical discharge, we developed a biophysical model of a PN receiving inputs from olfactory receptor neurons (ORNs) via nicotinic cholinergic synapses. The ORN is modeled as an inhomogeneous Poisson process whose firing rate is a function of time and is fitted to extracellular data recorded in response to pheromone stimulations at various concentrations and durations. The PN model is based on the Hodgkin-Huxley formalism with realistic ionic currents whose parameters were derived from previous studies. Simulations revealed that the inhibitory phase I can be produced by a SK current (Ca²⁺-gated small conductance K⁺ current) and that the excitatory phase E₂ can result from the long-lasting response of the ORNs. Parameter analysis further revealed that the ending time of E₁ depends on some parameters of SK, Ca²⁺, nACh and Na⁺ currents; I duration mainly depends on the time constant of intracellular Ca²⁺ dynamics, conductance of Ca²⁺ currents and some parameters of nACh currents; The mean firing frequency of E₁ and E₂ depends differentially on the interaction of various currents. Thus it is likely that the interplay between PN intrinsic currents and feedforward synaptic currents are sufficient to generate the triphasic firing patterns observed in the noctuid moth A. ipsilon.     

Demographics and Genetic Variability of the New World Bollworm (Helicoverpa zea) and the Old World Bollworm (Helicoverpa armigera) in Brazil

Helicoverpa armigera is one of the primary agricultural pests in the Old World, whereas H. zea is predominant in the New World. However, H. armigera was first documented in Brazil in 2013. Therefore, the geographical distribution, range of hosts, invasion source, and dispersal routes for H. armigera are poorly understood or unknown in Brazil. In this study, we used a phylogeographic analysis of natural H. armigera and H. zea populations to (1) assess the occurrence of both species on different hosts; (2) infer the demographic parameters and genetic structure; (3) determine the potential invasion and dispersal routes for H. armigera within the Brazilian territory; and (4) infer the geographical origin of H. armigera. We analyzed partial sequence data from the cytochrome c oxidase subunit I (COI) gene. We determined that H. armigera individuals were most prevalent on dicotyledonous hosts and that H. zea were most prevalent on maize crops, based on the samples collected between May 2012 and April 2013. The populations of both species showed signs of demographic expansion, and no genetic structure. The high genetic diversity and wide distribution of H. armigera in mid-2012 are consistent with an invasion period prior to the first reports of this species in the literature and/or multiple invasion events within the Brazilian territory. It was not possible to infer the invasion and dispersal routes of H. armigera with this dataset. However, joint analyses using sequences from the Old World indicated the presence of Chinese, Indian, and European lineages within the Brazilian populations of H. armigera. These results suggest that sustainable management plans for the control of H. armigera will be challenging considering the high genetic diversity, polyphagous feeding habits, and great potential mobility of this pest on numerous hosts, which favor the adaptation of this insect to diverse environments and control strategies.     

Blow Collection as a Non-Invasive Method for Measuring Cortisol in the Beluga (Delphinapterus leucas)

Non-invasive sampling techniques are increasingly being used to monitor glucocorticoids, such as cortisol, as indicators of stressor load and fitness in zoo and wildlife conservation, research and medicine. For cetaceans, exhaled breath condensate (blow) provides a unique sampling matrix for such purposes. The purpose of this work was to develop an appropriate collection methodology and validate the use of a commercially available EIA for measuring cortisol in blow samples collected from belugas (Delphinapterus leucas). Nitex membrane stretched over a petri dish provided the optimal method for collecting blow. A commercially available cortisol EIA for measuring human cortisol (detection limit 35 pg ml⁻¹) was adapted and validated for beluga cortisol using tests of parallelism, accuracy and recovery. Blow samples were collected from aquarium belugas during monthly health checks and during out of water examination, as well as from wild belugas. Two aquarium belugas showed increased blow cortisol between baseline samples and 30 minutes out of water (Baseline, 0.21 and 0.04 µg dl⁻¹; 30 minutes, 0.95 and 0.14 µg dl⁻¹). Six wild belugas also showed increases in blow cortisol between pre and post 1.5 hour examination (Pre 0.03, 0.23, 0.13, 0.19, 0.13, 0.04 µg dl⁻¹, Post 0.60, 0.31, 0.36, 0.24, 0.14, 0.16 µg dl⁻¹). Though this methodology needs further investigation, this study suggests that blow sampling is a good candidate for non-invasive monitoring of cortisol in belugas. It can be collected from both wild and aquarium animals efficiently for the purposes of health monitoring and research, and may ultimately be useful in obtaining data on wild populations, including endangered species, which are difficult to handle directly.     

Notes on a Cicada Parasitic Moth in Korea (Lepidoptera: Epipyropidae)

ABSTRACT The cicada parasitic moth Epipomponia nawai (Dyar) belonging to the family Epipyropidae is newly recorded from the Korean peninsula. Adults of both sexes, larva, and pupa are illustrated. Collecting data and host records for the species are also presented.     

Beauveria bassiana (Balsamo) Vuillemin - a Promising Microbial Control Agent of the Satin Moth (Lepidoptera: Lymantriidae)

A new isolate of the entomopathogenic fungus, Beauveria bassiana , was tested by laboratory bioassays for potential use as a microbial control agent of the early (third) and last (seventh) instars of the satin moth, Leucoma salicis L. Results demonstrate that this fungus is very effective against last instars of this lepidopteran pest. Although B. bassiana was cultured successfully from internal contents of all cadavers examined, vegetative hyphae emerged from intact cadavers of L. salicis infected as early (third) instar caterpillars only.