scholarly journals Ovicidal activity of spirotetramat and its effect on hatching, development and formation of Frankliniella occidentalis egg

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Xiaomin Yang ◽  
Guiying Zhou ◽  
Lijuan Sun ◽  
Changying Zheng
Keyword(s):  
Electron Microscopy ◽  
Crop Production ◽  
Frankliniella Occidentalis ◽  
Depth Of Field ◽  
Economic Damage ◽  
Ovicidal Activity ◽  
Transmission Electron ◽  
Egg Shells ◽  
Egg Shell ◽  
And Control

AbstractFrankliniella occidentalis (Pergande) has become an important vegetable pest worldwide because of its economic damage to crop production. However, it is difficult to control due to its unique living habits. In this study, the eggs of F. occidentalis were used as the target to explore the ovicidal activity of spirotetramat on the thrips and its effect on hatching, development and formation. After the treatment of spirotetramat, the LC50 value descreased with increased egg age using egg dipping method, and showed the same trend as the leaf dipping method verified on living plants. Through ultra-depth-of-field microscopy, scanning electron microscopy and transmission electron microscopy, the egg shell and internal structures of F. occidentalis eggs were studied. Spirotetramat can destroy the egg shells of F. occidentalis, resulting in shrinkage of the egg surface, sunken pores, egg deformities, egg shell rupture and other phenomena. This allows spirotetramat to enter the egg and destroy the egg structure, making the egg internal structure flocculent, fuzzy and unevenly distributed, which affects embryonic development and causes the nymphs to die before hatching. Therefore, the prevention and control of F. occidentalis using spirotetramat before damage is caused to crops should have a better effect.

scholarly journals Ultrastructure of digenean trematode eggs (Platyhelminthes: Neoophora): A review emphasizing new comparative data on four European Microphalloidea

2018 ◽  
Vol 63 (1) ◽  
pp. 1-14 ◽  
Author(s):  
David Bruce Conn ◽  
Zdzisław Świderski ◽  
Jordi Miquel
Keyword(s):  
Electron Microscopy ◽  
Myodes Glareolus ◽  
Trematode Species ◽  
Egg Formation ◽  
Transmission Electron ◽  
Egg Shells ◽  
Veterinary Importance ◽  
Egg Shell ◽  
Rana Lessonae

Abstract Despite their tremendous diversity and their medical and veterinary importance, details of egg ultrastructure among the digenean trematodes has been studied rather little. The available literature is spread over several decades and several species, but has not been adequately reviewed to reveal patterns of similarity and divergence. We present this review to synthesize and analyse what is known from the available literature reporting studies using both transmission electron microscopy (TEM) and scanning electron microscopy (SEM). To support our general review of existing literature, we also have synthesized our own previously published descriptions, and present herein our new previously unpublished data. From these new electron micrographs, we provide a comparative analysis of the intrauterine eggs of four digenean species, representing four genera and three families of the superfamily Microphalloidea, collected from four different host wildlife species in four European countries: 1) Mediogonimus jourdanei (Prosthogonimidae) from Myodes glareolus (Mammalia: Rodentia), collected in France; 2) Maritrema feliui (Microphallidae) from Crocidura russula (Mammalia: Soricimorpha), collected in Spain; 3) Brandesia turgida (Pleurogenidae) from Pelophylax ridibundus (Amphibia: Anura: Ranidae), collected in Russia; and 4) Prosotocus confusus (Pleurogenidae) from Rana lessonae (Amphibia: Anura: Ranidae), collected in Belarus. All were studied by preparing whole worms by various techniques for TEM, so that eggs could be studied in situ within the uterus of the parent worm. Based on the literature review and the new data presented here, we describe basic similarities in patterns of embryogenesis and egg formation among all trematode species, but substantial variations in timing of larvigenesis, sculpturing of egg shell surfaces, and some other features, especially including accessory cocoon coverings outside the egg shells of B. turgida and P. confusus. In the future, many more studies are needed to explore egg ultrastructure in other digenean taxa, to explore potential phylogenetic patterns in egg development and structure, and to correlate structure with function in the life cycle.

Plug-in scripts for EFTEM automation

1996 ◽  
Vol 54 ◽  
pp. 546-547
Author(s):  
N. D. Evans ◽  
M. K. Kundmann
Keyword(s):  
Electron Microscopy ◽  
National Laboratory ◽  
Oak Ridge ◽  
Multiple User ◽  
Transmission Electron ◽  
Short Period ◽  
User Facility ◽  
Instrument Control ◽  
And Control ◽  
Research Equipment

Post-column energy-filtered transmission electron microscopy (EFTEM) is inherently challenging as it requires the researcher to setup, align, and control both the microscope and the energy-filter. The software behind an EFTEM system is therefore critical to efficient, day-to-day application of this technique. This is particularly the case in a multiple-user environment such as at the Shared Research Equipment (SHaRE) User Facility at Oak Ridge National Laboratory. Here, visiting researchers, who may oe unfamiliar with the details of EFTEM, need to accomplish as much as possible in a relatively short period of time.We describe here our work in extending the base software of a commercially available EFTEM system in order to automate and streamline particular EFTEM tasks. The EFTEM system used is a Philips CM30 fitted with a Gatan Imaging Filter (GIF). The base software supplied with this system consists primarily of two Macintosh programs and a collection of add-ons (plug-ins) which provide instrument control, imaging, and data analysis facilities needed to perform EFTEM.

THE DEPOSITION AND CONTROL OF SELF ASSEMBLED SILICON NANO ISLANDS ON CRYSTALLINE SILICON

2008 ◽  
Vol 18 (04) ◽  
pp. 901-910
Author(s):  
RAGNAR KIEBACH ◽  
ZHENRUI YU ◽  
MARIANO ACEVES-MIJARES ◽  
DONGCAI BIAN ◽  
JINHUI DU
Keyword(s):  
Electron Microscopy ◽  
Integrated Circuit ◽  
Crystalline Silicon ◽  
Substrate Surface ◽  
Chemical Vapor ◽  
High Density ◽  
Transmission Electron ◽  
Pressure Chemical ◽  
And Control ◽  
Circuit Technology

The formation of nano sized Si structures during the annealing of silicon rich oxide (SRO) films was investigated. These films were synthesized by low pressure chemical vapor deposition (LPCVD) and used as precursors, a post-deposition thermal annealing leads to the formation of Si nano crystals in the SiO 2 matrix and Si nano islands ( Si nI ) at c-Si /SRO interface. The influences of the excess Si concentration, the incorporation of N in the SRO precursors, and the presence of a Si concentration gradient on the Si nI formation were studied. Additionally the influence of pre-deposition substrate surface treatments on the island formation was investigated. Therefore, the substrate surface was mechanical scratched, producing high density of net-like scratches on the surface. Scanning electron microscopy (SEM) and high resolution transmission electron microscopy (HRTEM) were used to characterize the synthesized nano islands. Results show that above mentioned parameters have significant influences on the Si nIs . High density nanosized Si islands can epitaxially grow from the c-Si substrate. The reported method is very simple and completely compatible with Si integrated circuit technology.

The Formation and Control of Laves Phase in K418 and 42CrMo Dissimilar Metal Laser Weld

2012 ◽  
Vol 166-169 ◽  
pp. 1839-1842 ◽  
Author(s):  
Ming Pang ◽  
Chang Zhen Liu ◽  
Guang Hui Xu ◽  
Jun Hua Ma
Keyword(s):  
Electron Microscopy ◽  
Heat Treatment ◽  
Post Weld Heat Treatment ◽  
Laves Phase ◽  
Laser Weld ◽  
Dissimilar Metal ◽  
Weld Metals ◽  
Transmission Electron ◽  
And Control ◽  
Weld Heat

The effect of K418 and 42CrMo dissimilar metal laser welding velocity, temperature of post-weld heat treatment on controlling formation of laves phase were investigated. Microstructure and laves phase were characterized by optical microscopy (OM), scanning electron microscopy (SEM) and transmission electron microscopy (TEM).Results showed that Laves phase formed in the interdendritic regions of the weld metals as a result of segregation. The morphology and composition of Laves phase depended strongly on heat input/cooling rate and influenced its response to subsequent homogenization post-weld heat treatment.

Characterization of Multilayer Thin Film Structures for Gas Sensor Applications

1995 ◽  
Vol 382 ◽  
Author(s):  
M. Dibattista ◽  
S. V. Patel ◽  
K. D. Wise ◽  
J. L. Gland ◽  
J. F. Mansfield ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Gas Sensor ◽  
Environmental Scanning Electron Microscopy ◽  
Environmental Scanning ◽  
Sensing Properties ◽  
Force Microscopy ◽  
Sensor Applications ◽  
Transmission Electron ◽  
Silicon Based ◽  
And Control

ABSTRACTA nicrofabricated silicon-based chemical gas sensor with a discontinuous film of Pt / TiOx, as the active sensing component has been characterized by atomic force microscopy, environmental scanning electron microscopy, and transmission electron microscopy. A study of the device's multilayer structure and of the thin sensing film is undertaken to understand and control the sensing properties of the metal / semiconducting materials. The purpose of this research is to advance the understanding of the conduction mechanism and provide a basis for optimizing the sensing properties and microstructure of the sensing device.

scholarly journals The epidemiology and control ofSalmonella thompsoninfection of fowls

1947 ◽  
Vol 45 (3) ◽  
pp. 265-281 ◽  
Author(s):  
A. Buxton ◽  
R. F. Gordon
Keyword(s):  
Storage Conditions ◽  
Blood Testing ◽  
Hatching Time ◽  
Heat Treated ◽  
Faecal Samples ◽  
Egg Shells ◽  
The Common ◽  
Egg Shell ◽  
And Control ◽  
Formaldehyde Vapour

The details are given of the epidemiology ofS. thompsoninfection in a flock of pullets which survived an outbreak of this disease when chicks, and also of a flock of adult birds suspected of being carriers of the organism. The results of blood testing and bacteriological examinations of cloacal swabs, random faecal samples and eggs from both flocks indicated that:(1) Many chicks which survived an outbreak ofS. thompsoncontinued to carry the organism for some months without showing any symptoms. In most cases the organism was harboured in the intestines and was excreted intermittently in the faeces. On one occasionS. thompsoninfected the gall bladder, and the bacilli were excreted in the faeces for at least 18 months after the outbreak had occurred.(2) The common method of egg infection was by the contamination of the shell with infected faeces. Under conditions of incubation the bacilli penetrated the egg shell and infected the yolk. Although there was little penetration of the organism under storage conditions, the bacilli on infected shells remained viable for at least 21 days.(3) The common methods of spreading infection in a hatchery were from:(a) The contact of infected and non-infected egg shells.(b) The handling of eggs before and during incubation.(c) The contact of egg shells with infected incubators.(d) The ingestion and inhalation of infected fluff and incubator debris at hatching time.(e) The ingestion of food and water contaminated with infected faeces from survivor chicks.For the control ofS. thompsoninfection in poultry, the following procedures have been recommended:(1) The production of agglutinins by carrier birds was not a reliable indication of infection. In known infected flocks, however, the detection of carriers by blood testing and by the examination of cloacal swabs is of value. For such a test an alcoholized antigen is preferable to a heat-treated broth antigen, and a titre of 1/20 or more should be regarded as an indication that a bird is infected.(2) Only clean eggs should be used for hatching. Dirty egg shells should be cleaned by scraping or brushing and not by wiping with a damp cloth.(3) Fertile eggs should be stored in a cool, dry atmosphere for as short a period as possible before incubation.(4) Eggs should be fumigated in the incubator with formaldehyde vapour, not later than 24 hr. after they have been set.We wish to record our appreciation of the assistance received from Mrs E. Sidery in the bacteriological examination of eggs and the preparation of agglutination tests.

Studies withBrugia pahangi. 14. Intrauterine development of the microfilaria and a comparison with other filarial species

1976 ◽  
Vol 50 (4) ◽  
pp. 251-257 ◽  
Author(s):  
Rosemary Rogers ◽  
D. S. Ellis ◽  
D. A. Denham
Keyword(s):  
Electron Microscopy ◽  
Light And Electron Microscopy ◽  
Uterine Wall ◽  
Dense Material ◽  
Intrauterine Development ◽  
Brugia Pahangi ◽  
Electron Dense Material ◽  
Large Numbers ◽  
Egg Shells ◽  
Egg Shell

ABSTRACTThe intrauterine development ofBrugia pahangiembryos was followed from after fertilization to birth, using light and electron microscopy. The origin and development of the sheath of the microfilaria and its Possible role in the nutrition of the developing embryo were particularly investigated. Comparisons were drawn with the intrauterine development of other filarial species. The egg shell of theB. pahangiembryo js distinct from the oolemma and forms the sheath of the microfilaria. It is suggested that the electron dense material released by cells of the uterine wall and passing along the channels between the egg shells of adjacent embryos is nutritive. The death of large numbers of developing embryos in the central uterine Jumen is probably caused by overcrowding as their size rapidly increases, leading to nutritional deficiency.

scholarly journals PCR-RFLP method to distinguish Frankliniella occidentalis, Frankliniella intonsa, Frankliniella pallida and Frankliniella tenuicornis

2016 ◽  
Vol 56 (1) ◽  
pp. 60-66 ◽  
Author(s):  
Arnika Przybylska ◽  
Żaneta Fiedler ◽  
Aleksandra Obrępalska-Stęplowska
Keyword(s):  
Crop Production ◽  
Frankliniella Occidentalis ◽  
Plant Protection ◽  
Pcr Amplification ◽  
Restriction Enzymes ◽  
Wild Plants ◽  
Universal Primers ◽  
Economic Damage ◽  
Its1 Rdna ◽  
Species Specific

Abstract Thrips from the genus Frankliniella (Thysanoptera, Thripidae) are phytophagous on crops and wild plants. Some of them cause slight economic damage, however, others including F. occidentalis and F. intonsa are responsible for considerable losses in crop production. Moreover, they constitute a double threat for host plants by not only feeding on them but also vectoring viruses, some of which are on the quarantined list of the European Plant Protection Organization. The rapid detection and differentiation between more and less harmful Frankliniella species is, therefore, important in order to combat the pests at the time of their appearance. In this study, we have undertaken to develop a method of detecting F. occidentalis, F. intonsa, F. pallida, and F. tenuicornis. The protocol is based on PCR amplification of ITS1 rDNA fragments of these insects using universal primers pair giving products of slightly distinct length for studied insects. Restriction enzymes digestion which is easy to interpret, allows for visible differentiation of all these Frankliniella species. The method was shown to be species-specific and sensitive. Even single specimens in either the larvae or adult stage could be distinguished.

scholarly journals In-Plane Texturing in Sputtered Films

2000 ◽  
Vol 34 (2-3) ◽  
pp. 91-103 ◽  
Author(s):  
J. F. Whitacre ◽  
S. M. Yalisove ◽  
J. C. Bilello
Keyword(s):  
Electron Microscopy ◽  
Texture Evolution ◽  
Grazing Incidence ◽  
X Ray ◽  
Sputtered Films ◽  
X Ray Scattering ◽  
Transmission Electron ◽  
Out Of Plane ◽  
And Control ◽  
Average Angle

Films consisting of Mo, Cr, and Ta have all been found to display well-defined biaxial textures when grown under certain conditions. A well-defined out-of-plane texture evolves within the first ~ 100 nm of the film, followed by the evolution of a preferred crystallographic orientation in the plane of the film. These effect were studied using X-ray pole figure analysis, scanning electron microscopy (SEM), transmission electron microscopy (TEM), transmission electron diffraction (TED), and high resolution grazing incidence X-ray scattering (GIXS). It has been found that in-plane texture evolves only when there is, on average, oblique adatom flux incident onto the substrate. Further, the type of out-of-plane texture can be controlled by altering the deposition conditions. Parameters including cathode-to-substrate distance, deposition rate, average angle of adatom incidence, and sputter gas pressure, have been shown to determine the type out-of-plane texture, as well as the rate of in-plane texture evolution. The studies conducted have shown that it is possible to create and control biaxially textured films and multilayers made of a variety of materials. A recent model which describes this phenomena is discussed.

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