Seasonal Population Trends and Extensive Census Methods for Hyphantria cunea

1967 ◽  
Vol 99 (1) ◽  
pp. 9-17 ◽  
Author(s):  
R. F. Morris ◽  
C. W. Bennett

AbstractThis is the fourth in a series of papers leading to the development of population models for Hyphantria cunea Drury in New Brunswick and Nova Scotia. In 1961 and 1962 seasonal trends were obtained for moth eclosion, larval development, nest population, parasitism, and other factors. It is concluded that one annual census of nests from a moving vehicle can provide an effective method for comparing changes in population and natural control factors over diverse climatic areas. The timing of the census in each area is important, as well as the collection of nests for data on development, colony size, parasitism, and predation.The seasonal trends also add support to earlier hypotheses concerning the role of weather in the population dynamics of H. cunea, and reveal the nature of an important interaction between the mortality induced by weather and that induced by the main parasite, Campoplex validus Cress.

1972 ◽  
Vol 104 (8) ◽  
pp. 1197-1207 ◽  
Author(s):  
R. F. Morris

AbstractThe number of predators inhabiting nests of Hyphantria cunea Drury was recorded annually for 13 years in four areas in New Brunswick and two areas on the coast of Nova Scotia. The most common groups were the pentatomids and spiders, which sometimes reproduced within the nests, but the mean number per nest was low in relation to the number of H. cunea larvae in the colonies. The rate of predation on fifth-instar larvae was low. Small or timid predators appeared to prey largely on moribund larvae or small saprophagans during the principal defoliating instars of H. cunea.No relationship could be detected between the number of larvae reaching the fifth instar and the number of predators in the colony; nor could any functional or numerical response of the predators to either the initial number of larvae per colony or the population density of colonies be found. It is concluded that the influence of the nest-inhabiting predators is small and relatively stable, and may be treated as a constant in the development of models to explain the population dynamics of H. cunea.H. cunea is a pest in parts of Europe and Asia, where it has been accidentally introduced from North America. The introduction to other continents of the North American predator, Podisus maculiventiis (Say), is discussed briefly.


Author(s):  
V.V. Kupriyanov ◽  
◽  
I.S. Bondarenko ◽  

The common problem was studied concerning the personnel safety and the operation of railway transport during industrial cargo transportation. Statistical and technical analysis were conducted related to the conditions and reasons of railway accidents caused by various hazardous factors and occurred over the past 15 years in the mining industry of Russia. The study based on natural, technical, and organizational factors showed that there is a steady tendency towards the preservation of the number of accidents such as train collisions, fires, and derailments. Despite the measures taken, such accidents do occur resulting in fatal accidents. The situation is explained by the fact that safety of rail transport is conditioned by the factors that can be divided into difficult-to-control and complex (coordinated by action). The differences between complex factors caused by the railway technology and difficult-to-control factors, which include natural factors or their combination with the stimulated factors are studied in the article. Study of the evidence including the details of the development of fires and derailments of trains from the rails, the consequences of such accidents and conclusions about their causes shows that the additional calculations and classification of the difficult-to-control factors in combination with other causes allow to give a more detailed assessment of the nature of difficult-to-control factors and the interrelationship between them. Through this it becomes possible to detect the maximum number of violations. It is concluded that improving railway safety is possible only with a differentiated approach to the role of each group of factors including difficult-to-control factors, and the ability of personnel to influence the occurrence and development of accidents. The time characteristics of railway accidents are considered. The idea of automated information filtering of clogged messages in the analysis of accidents is formulated.


2021 ◽  
Author(s):  
Sarah Coldwell King

A Traffic Light Decision Support System (DSS) used in marine finfish federal environmental assessments was expanded to include regional and cumulative environmental impacts. A retrospective review of 23 existing mariculture farms in southwestern New Brunswick indicated whether cumulative interactions would have justified site approvals. Six new criteria were added to the far-field component and other existing criteria were amended. Scores of A, B+, B⁻, C and pre-emptive C were based on acceptability criteria. Calculations of cumulative ecosystem indices and potential site indices revealed site acceptability, and the index combinations suggested potential site approvals predicted using Hargrave's (2002) three-colour Traffic Light scheme. Before mitigation was considered, 19 of 23 sites failed the amended set of criteria and after considering mitigation, 8 sites failed. Combining the site and ecosystem indices yielded varying site acceptability scores. The role of mitigation and other factors in hindering sustainable siting was discussed


2008 ◽  
Vol 19 (1) ◽  
pp. 45-45 ◽  
Author(s):  
Natalie G. Robinson ◽  
Katherine M. White ◽  
Ross McD. Young ◽  
Peter J. Anderson ◽  
Melissa K. Hyde ◽  
...  

1937 ◽  
Vol 69 (7) ◽  
pp. 145-146
Author(s):  
F. C. Gilliatt

Eulia mariana Fern. was identified in Annapolis Valley orchards about twelve years ago and since has become one of the major orchard pests. Although outbreaks continue to occur, fruit growers should fully appreciate the value of natural control, which in one form or another is always assisting in keeping this insect in check. The various natural control factors may be recorded as follows:(1) Mortality of pupae. (2) Parasites of larvae and pupae. (3) Parasites of eggs. (4) Predators.


2013 ◽  
Vol 288 (23) ◽  
pp. 17008-17018 ◽  
Author(s):  
D. Fernando Estrada ◽  
Jennifer S. Laurence ◽  
Emily E. Scott

The membrane heme protein cytochrome b5 (b5) can enhance, inhibit, or have no effect on cytochrome P450 (P450) catalysis, depending on the specific P450, substrate, and reaction conditions, but the structural basis remains unclear. Here the interactions between the soluble domain of microsomal b5 and the catalytic domain of the bifunctional steroidogenic cytochrome P450 17A1 (CYP17A1) were investigated. CYP17A1 performs both steroid hydroxylation, which is unaffected by b5, and an androgen-forming lyase reaction that is facilitated 10-fold by b5. NMR chemical shift mapping of b5 titrations with CYP17A1 indicates that the interaction occurs in an intermediate exchange regime and identifies charged surface residues involved in the protein/protein interface. The role of these residues is confirmed by disruption of the complex upon mutagenesis of either the anionic b5 residues (Glu-48 or Glu-49) or the corresponding cationic CYP17A1 residues (Arg-347, Arg-358, or Arg-449). Cytochrome b5 binding to CYP17A1 is also mutually exclusive with binding of NADPH-cytochrome P450 reductase. To probe the differential effects of b5 on the two CYP17A1-mediated reactions and, thus, communication between the superficial b5 binding site and the buried CYP17A1 active site, CYP17A1/b5 complex formation was characterized with either hydroxylase or lyase substrates bound to CYP17A1. Significantly, the CYP17A1/b5 interaction is stronger when the hydroxylase substrate pregnenolone is present in the CYP17A1 active site than when the lyase substrate 17α-hydroxypregnenolone is in the active site. These findings form the basis for a clearer understanding of this important interaction by directly measuring the reversible binding of the two proteins, providing evidence of communication between the CYP17A1 active site and the superficial proximal b5 binding site.


Author(s):  
Faye Margaret Kert

This journal examines privateering and naval prizes in Atlantic Canada in the maritime War of 1812 - considered the final major international manifestation of the practice. It seeks to contextualise the role of privateering in the nineteenth century; determine the causes of, and reactions to, the War of 1812; determine the legal evolution of prize law in North America; discuss the privateers of Nova Scotia and New Brunswick, and the methods they utilised to manipulate the rules of prize making during the war; and consider the economic impact of the war of maritime communities. Ultimately, the purpose of the journal is to examine privateering as an occupation in order to redeem its historically negative reputation. The volume is presented as six chapters, plus a conclusion appraising privateering, and seven appendices containing court details, prize listings, and relevant letters of agency.


1978 ◽  
Vol 56 (6) ◽  
pp. 470-473 ◽  
Author(s):  
Theodore L. Sourkes ◽  
Krystyna Missala

1. The ability of rats to metabolize radioactive putrescine to 14CO2 in vivo has been studied. 2. Animals made deficient in pyridoxine exhibit a significantly lower rate of catabolism of the diamine. 3. There does not appear to be an important interaction between the effects of the deficiency and those stemming from treatment of the animals with the diamine oxidase inhibitor aminoguanidine. 4. These results favour the concept of a role of pyridoxal cofactor in the metabolism of diamines, presumably at the diamine oxidase stage.


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