Your search resulted in 43 documents. Displaying 25 entries per page.
Implications for comparability of laboratory experiments revealed in studies on the effects of population density on the vigour in groups of Coptotermes lacteus (Frogatt) and Nasutitermes exitiosus(Hill) (Isoptera: Rhinotermitidae, Termitidae)
1983 - IRG/WP 1194
The vigour - survival. and wood consumption - of groups of Coptotermes lacteus and Nasutitermes exitiosus was measured when termites were kept at different population densities (g termites/mL) by changing group size and/or volume of the holding container. A characteristic pattern emerges for subterranean-like termite species. At low population densities (<0.01 g/mL) performance of termites impr...
M Lenz, R A Barrett, E R Williams
Strategies of risk reduction in sensitive environments - Case studies
2001 - IRG/WP 01-50166-11
The application of risk assessment procedures is based on widely agreed criteria and, whenever necessary, default values. The assessment itself aims to cover a wide extent of situations through "reasonable worst case scenarios". The result, based on the ratio of predictive to no-effect concentrations "PEC/PNEC", is usually performed into various regulations on a pass/fail basis, practically by ban...
G Ozanne
Biodetioration and strength reductions in preservative treated aspen waferboard
1983 - IRG/WP 2195
Experimental aspen waferboards, bonded with liquid or powdered phenol formaldehyde resins and treated by various methods with a wide selection of preservatives, were tested for fungal resistance in accelerated laboratory trials. Mold growth on the surface as well as weight and strength losses due to the actions of decay fungi were determined. Testing of board strength after decay in high and moder...
E L Schmidt, H J Hall, R O Gertjejansen, R C De Groot
Determination of toxicity data for preservatives against Basidiomycetes by measuring the reduction in compression strength of wood
1988 - IRG/WP 2297
Blocks of Pinus radiata D. Don were treated to 12 retention levels with CCA and NaPCP. These were exposed for 12 weeks in agar jars to the dry rot (brown rot) Serpula lacrymans (Schum. ex Fr.) S.F. Gray. After mass loss determination, the same blocks were tested for reduction in compression strength parallel to the grain. Using both these parameters, together with interpolated 6 week strength loss...
J Wazny, J D Thornton
A study of methanogenesis and sulphate-reduction: A possible source of explosive gas mixtures in a gold mine
1989 - IRG/WP 1399
Previous work isolated anaerobic bacteria from timbers and drainage water in a gold mine. The present work identifies the predominant methanogen in the mine ecosystem as Methanobacterium bryantii and sulphate-reducing isolates as Desulphovibrio desulphuricans and Desulphotomaculum antarcticum. Laboratory studies using model systems evaluate the activity of methanogenic and sulphate-reducing bacter...
L D Abraham, J F Putterill, A A W Baecker
Implications for comparability of laboratory experiments revealed in studies on the effects of population density on the vigour in groups of Coptotermes lacteus (Froggatt) and Nasutitermes exitiosus(Hill) (Isoptera: Rhinotermitidae, Termitidae)
1983 - IRG/WP 1197
(Summary of paper 1194)
The vigour - survival and wood consumption - of groups of Coptotermes lacteus and Nasutitermes exitiosus was measured when termites were kept at different population densities (g termites/ mL) by changing group size and/or volume of the holding container. A characteristic pattern emerged. At low population densities (< 0,01 g/mL) performance of termites improved with an increase in group size; at higher population densities it tended to decline. The impact of altering group size and container volume on termite vigour was most pronounced at low densities; at higher population densities, performance tended to be more stable but declined markedly when termites became overcrowded. In most jar-type experiments on termites, especially those conducted in Europe and the U.S.A., small groups of termites are housed in disproportionately large jars, resulting in very low, sub-optimal population densities. Suggestions are made for improvements in experimental design that would lead to an enhancement of the comparability of results from different laboratories.
M Lenz, R A Barrett, E R Williams
Social and economocal impact of an extension of service life resulting of an adequate preventive treatment. Application to wooden components used in urban areas with a high density of population
1993 - IRG/WP 93-50001-15
Le document évalue les problèmes rencontrés en zone urbaine pour le sauvetage des constructions: coordination de la lutte, délimination des chantieres et des périmètres d'investigation, nuisances causées par les interventions, risques pour la santé, risques pour l'environnement. Coûts. Comparaison socio-économique du traitement préventif et des interventions à posteri...
A T De Lelis, G A C Lopez
What is OECD doing to promote harmonization of biocide regulations
1999 - IRG/WP 99-20182
OECD began work on biocides in 1997 to help Member countries co-operate in the assessment and registration of these products. The work is a part of OECD's Pesticide Programme, and is co-ordinated by the Biocides Steering Group. The goal is to harmonize regulatory approaches to allow countries to conduct evaluations of biocides more efficiently. More efficient evaluations can advance the p...
M Paneli, N Grandy
The influence of cement and calcium compounds on the performance of CCA preservatives
1983 - IRG/WP 3221
The influence of cement and calcium compounds on the durability of untreated and CCA treated wood is considered. Calcium compounds were found to reduce the toxicity of a CCA preservative to a soft rot fungus at copper to calcium ratios of 1:1 and 1:10 using a cellulose filter paper technique. Further studies are outlined and some possible mechanisms by which cement and calcium compounds may affect...
R J Murphy
Chelator-Mediated Fenton Chemistry in Wood Degraded by Fungi
2007 - IRG/WP 07-10618
Wood specimens were colonized by individual isolates of brown rot, white rot, soft rot and blue (sap) stain fungi. Ethyl acetate extracts of the ground wood were analyzed for their iron-reducing capabilities using a ferrozine-based assay. Extracts from wood colonized by brown rot fungi showed a significantly greater iron-reducing capability than extracts from wood colonized by white rot fungi or n...
B Goodell, G Daniel, J Jellison, Yuhui Qian
Reduction of Environmental Toxicity Through Eco-friendly Wood Biopreservative
2007 - IRG/WP 07-50243
Many chemicals are used today to enhance the durability of wood and wood-derived products that are very important in our life. Such chemicals are copper, chromium, arsenate, zinc, etc. Though these preservatives are useful to protect wood from biodeterioration, but environmental toxicity is also related with them. The present study is to investigate the fungitoxic activities of Dalbergia sissoo le...
A Humayan Kabir, M Firoz Alam
Effects of Nano-Wollastonite on Ignition Time Reduction in MDF
2012 - IRG/WP 12-40576
Effects of wollastonite nano-fibers on ignition time reduction in medium density fiberboard were studied. Nanowollastonite was applied at 5, 10, 15, and 20 g/kg dry weight basis of wood fibers and compared with control specimens. Two application methods of nanowollastonite were used: surface application, and internal application. Specimens of 150×130×9 mm were prepared and the ignition times wer...
H Reza Taghiyari, H Rangavar, P Noori, A Karimi
Hydrogels: a solution to reduce boron leachability without reduction of its biodisponibility to wood decaying fungi?
2012 - IRG/WP 12-30602
Products used today for wood protection must fulfill to more and more environmental constraints, such as being of low toxicity in answer to the Biocidal Product Directory, but also to involve waterborne treatments to limit rejection of volatile organic compounds in the atmosphere. Boron preservatives have been described as valuable alternatives for wood protection for non-ground contact applicatio...
F Obounou Akong, P Gérardin, M-F Thévenon, S Parant, C Gérardin-Charbonnier
Is there a role for termite alates in colony expansion in Wisconsin?
2014 - IRG/WP 14-10820
Termite colonies in Wisconsin tend to be large and widely spread out geographically, and separated by distances up to 1342km. We recently completed a study to determine the genetic diversity and population substructure of thirteen existing colonies of Reticulitermes flavipes using amplified fragment length polymorphism to determine patterns of termite dispersal in Wisconsin. Measures of inbreedin...
F Green III, R A Arango, G R Esenther, T G Shelton
New approach to improve the estimation of colony population in subterranean termites (Blattodea: Rhinotermitidae)
2016 - IRG/WP 16-10866
The aim of this study was to estimate the mortality and fading effects of dye markers Neutral red and Nile blue commonly used in the estimation of termite colony population, in order to determine the decrease rate from the initial number of marked and released termites. This rate can be considered in the application of the different indexes used to calculate the number of termites of the colony. I...
E Alcaide, R Molero, J Diz, M Gaju
Use of x-ray microdensitometry for assessing the resistance to the fungus C puteana of a hybrid larches population
2018 - IRG/WP 18-10923
The aim of this research was to utilize the X-ray microdensitometry to determine the natural durability and its variability of a hybrid larch population. The method was applied on slices obtained by increment cores collected on standing trees before cutting them down. The methodology was discussed also in order to propose as a new screening method especially suited for trees populations. X-ray mic...
S Palanti, F Alderighi, F Stefani, J P Charpentier, L E Pâques
The iron reduction by chemical components of wood blocks decayed by wood rotting fungi
2021 - IRG/WP 21-10979
Brown-rot fungi, a group of wood rotting fungi, is well known to be one of major microorganisms that cause the deterioration of wooden buildings in Japan and have been considered to use chelator-mediated Fenton (CMF) reaction in concert with hydrolytic and redox enzymes for degradation of wood cell wall. CMF can be described as a non-enzymatic degradation system that utilizes hydroxyl radicals pro...
R R Kondo, Y Horikawa, K Ando, B Goodell, M Yoshida
Effect of enzymatic inhibitors on the population of Reticulitermes grassei and their associated microbiota
2023 - IRG/WP 23-11008
Termites are pests that invade urban, agricultural and forest environments worldwide. They are economically important owing to the damage they cause to wood, wood products, building materials, agricultural products and forests. There are many methods for its control, but many of them cause negative environmental effects due to their toxicity. In termites, dietary change or antibiotic treatment may...
S M Santos, M T Troya, F Llinares, P Colina, E García, M Álvarez, L Robertson