scholarly journals Mortality Patterns in Coptotermes gestroi (Blattodea: Rhinotermitidae) Following Horizontal Transfer of Nonrepellent and Repellent Insecticides: Effects of Donor:Recipient Ratio and Exposure Time

2014 ◽  
Vol 107 (4) ◽  
pp. 1563-1572
Author(s):  
Kok-Boon Neoh ◽  
Boon-Hoi Yeoh ◽  
Chow-Yang Lee
Keyword(s):  
Exposure Time ◽  
Horizontal Transfer ◽  
Coptotermes Gestroi

scholarly journals AVALIAÇÃO DE ESTACAS DE Pinus sp. COMO ISCA-ARMADILHA EM DIVERSOS PERÍODOS DE EXPOSIÇÃO A CUPINS SUBTERRÂNEOS

FLORESTA ◽  
2010 ◽  
Vol 40 (1) ◽  
Author(s):  
Marcus Nascimento Santos ◽  
Maria Lúcia França Teixeira ◽  
Maurício Ballesteiro Pereira ◽  
Eurípedes Barsanulfo Menezes
Keyword(s):  
Organic Matter ◽  
Exposure Time ◽  
Rio De Janeiro ◽  
Botanical Garden ◽  
Subterranean Termites ◽  
Distilled Water ◽  
Bait Trap ◽  
Prolonged Effect ◽  
Coptotermes Gestroi ◽  
Low Incidence

Este estudo teve como objetivo avaliar estacas de Pinus sp. como isca-armadilha em vários períodos de exposição a cupins subterrâneos em áreas com diferentes composições florísticas no Jardim Botânico do Rio de Janeiro (JBRJ). As iscas-armadilha (previamente embebidas em água destilada por 0, 24 e 48 horas) foram enterradas ao mesmo tempo em três áreas do JBRJ, para retiradas mensais em grupos com exposição de 1 a 12 meses a Coptotermes gestroi (Wasmann) e Heterotermes longiceps (Snyder) (Isoptera: Rhinotermitidae). Houve diferença estatística sobre o tempo de exposição às iscas-armadilha e não houve diferença para um período de imersão em água. Concluiu-se que as iscas-armadilha são naturalmente atraentes para os cupins subterrâneos, e não necessitam de prévia imersão em água destilada para aumentar sua maciez. O tempo de permanência da isca-armadilha no solo não deve exceder a 3 meses para Coptotermes gestroi, em condições de alta luminosidade solar e escassa disponibilidade de matéria orgânica no solo, enquanto que para Heterotermes longiceps, o tempo de exposição pode ser de até 12 meses, em condições de baixa luminosidade e maior disponibilidade de matéria orgânica, fato a ser considerado em programas de controle de cupins. Palavras-chave: Comportamento de cupins; Isoptera; Coptotermes gestroi; Heterotermes longiceps.   Abstract Evaluation of Pinus sp. stakes as bait-trap with several periods of exposure to subterranean termites. This study aimed to evaluate stakes of Pinus sp. as bait-trap for several periods of exposure to subterranean termites in areas of different floristic compositions in the Botanical Garden of Rio de Janeiro (JBRJ). Bait-traps were previously immersed in distilled water for 0, 24 or 48 hours. They were buried in three areas of JBRJ for monthly withdrawals in groups with exposure of 1 to 12 months on the species of subterranean termite, Coptotermes gestroi (Wasmann) and Heterotermes longiceps (Snyder). We observed statistical difference on exposure time of the bait-trap,but no difference for the period of immersion in water. We concluded that the bait-trap are naturally attractive to subterranean termites and do not require immersion in distilled water previously in order to increasing their softness. The exposure time of the bait-trap in soil should not exceed 3 months to C. gestroi, under conditions of prolonged effect of sunlight and scarce availability of organic matter, while for H. longiceps the exposure time can be extended to 12 months under conditions of low incidence of sunlight and high availability of organic matter, facts that must be considered on termites control programs.Keywords: Termite's behavior; Isoptera; Coptotermes gestroi; Heterotermes longiceps.

Progress In The Practical Application Of Automated Image Analysis To Tem Negatives

1977 ◽  
Vol 35 ◽  
pp. 214-217
Author(s):  
F. A. Heckman ◽  
E. Redman ◽  
J.E. Connolly
Keyword(s):  
Image Analysis ◽  
Image Quality ◽  
Exposure Time ◽  
Image Contrast ◽  
Automated Image Analysis ◽  
Practical Application ◽  
Factors Affecting ◽  
High Image Quality ◽  
Qualitative Evidence ◽  
Comprehensive Study

In our initial publication on this subject1) we reported results demonstrating that contrast is the most important factor in producing the high image quality required for reliable image analysis. We also listed the factors which enhance contrast in order of the experimentally determined magnitude of their effect. The two most powerful factors affecting image contrast attainable with sheet film are beam intensity and KV. At that time we had only qualitative evidence for the ranking of enhancing factors. Later we carried out the densitometric measurements which led to the results outlined below.Meaningful evaluations of the cause-effect relationships among the considerable number of variables in preparing EM negatives depend on doing things in a systematic way, varying only one parameter at a time. Unless otherwise noted, we adhered to the following procedure evolved during our comprehensive study:Philips EM-300; 30μ objective aperature; magnification 7000- 12000X, exposure time 1 second, anti-contamination device operating.

Structure images of Si, Ge and Mos2 crystals and some application to radiation damage studies

1978 ◽  
Vol 36 (1) ◽  
pp. 292-293 ◽  
Author(s):  
K. Izui ◽  
T. Nishida ◽  
S. Furuno ◽  
H. Otsu ◽  
S. Kuwabara
Keyword(s):  
Radiation Damage ◽  
Exposure Time ◽  
Gaussian Distribution ◽  
Intensity Distribution ◽  
Chromatic Aberration ◽  
Magnetic Lens

Recently we have observed the structure images of silicon in the (110), (111) and (100) projection respectively, and then examined the optimum defocus and thickness ranges for the formation of such images on the basis of calculations of image contrasts using the n-slice theory. The present paper reports the effects of a chromatic aberration and a slight misorientation on the images, and also presents some applications of structure images of Si, Ge and MoS2 to the radiation damage studies.(1) Effect of a chromatic aberration and slight misorientation: There is an inevitable fluctuation in the amount of defocus due to a chromatic aberration originating from the fluctuations both in the energies of electrons and in the magnetic lens current. The actual image is a results of superposition of those fluctuated images during the exposure time. Assuming the Gaussian distribution for defocus, Δf around the optimum defocus value Δf0, the intensity distribution, I(x,y) in the image formed by this fluctuation is given by

Methods of experimental polyploidization and their use in apple breeding

2020 ◽  
Vol 62 ◽  
pp. 85-90
Author(s):  
L. V. Tashmatova ◽  
O. V. Matsneva ◽  
T. M. Khromova ◽  
V. V. Shakhov
Keyword(s):  
Exposure Time ◽  
Cell Walls ◽  
Prolonged Exposure ◽  
Ornamental Plants ◽  
Colchicine Treatment ◽  
Apple Trees ◽  
Open Ground ◽  
High Concentrations ◽  
Diploid Gametes

The article presents methods of experimental polyploidy of fruit, berry and ornamental plants. The purpose of this review is to highlight the problems and prospects of polyploidization of plants in the open ground and in vitro culture and the possibility of their application for apple trees. For the purpose of obtaining apple tetraploids as donors of diploid gametes, seed seedlings were treated with a solution of colchicine in concentrations of 0.1-0.4 % for 24 and 48 hours. Colchicine concentrations of 0.3 % and 0.4 % at 48 hours of treatment had a detrimental eff ect on their development. As a result, tetraploids and chimeras were obtained from seeds from free pollination of the varieties Orlik, Svezhest, Kandil Orlovsky, as well as from seeds obtained from crossing the varieties Svezhest×Bolotovskoe, Moskovskoe Оzherel’e×Imrus, Girlyanda×Venyaminovskoe. The optimal concentration of colchicine was 0.1 %. Methods of colchicine treatment have been studied: 1) adding to the nutrient medium, colchicine concentration: 0.01%, 0.02%, exposure time 24h-19 days; 2) applying amitotic solution to the growth point, colchicine concentration: 0.1 %, 0.2 %, exposure time 24h-7 days. To increase the penetration of colchicine through the cell walls, a 0.1 % dimexide solution was used. Studies have shown that high concentrations and prolonged exposure to colchicine reduce the viability of explants.

Sign in / Sign up

Export Citation Format

Share Document