Natural Sciences And Engineering Research Council Research Articles

A Stochastic Salvo Model Analysis of the Battle of the Coral Sea

Natural Sciences and Engineering Research Council (NSERC) Discovery Grant; Carleton University Centre for Security & Defense Studies.

Biochemical Markers of Neurotoxicity in Wildlife and Human Populations: Considerations for Method Development

Disruption of neurochemical parameters in blood and brain tissues can be used as early biomarkers of neurotoxicity in human and wildlife epidemiological studies. To investigate the feasibility of biomarker measurements in field samples obtained from remote locations, tissue storage limits were determined with human blood and mink cortex tissue using efficient and cost-effective microplate assays. Results show that isolated blood platelets and plasma can be stored at 4°C for 4 wk before measurement of monoamine oxidase (MAO) and cholinesterase (ChE) activities, while human lymphocytes can be stored at 4°C for up to 2 d before muscarinic acetylcholine (mACh) receptor binding analysis. Blood cells stored frozen resulted in decreased MAO activity and mACh receptor function. These data suggest that mink brain tissue obtained from field samples can be stored at various temperatures without affecting dopamine (D2) and mACh receptor densities; however, MAO and ChE activities were most stable in samples stored in a −20°C domestic freezer or at 4°C. Multiple freeze/thaw cycles alter mACh and D2 receptors and MAO activity in mink cortex samples and should therefore be minimized. In conclusion, these neurochemical biomarkers can efficiently be measured in large human and wildlife neurotoxicity studies, provided proper storage conditions are maintained. This study was financially supported by the Collaborative Mercury Research Network (COMERN) and the Natural Science and Engineering Research Council (NSERC) of Canada. C. J. Stamler and N. Basu are both recipients of NSERC postgraduate fellowships. We also thank Mary Gamberg (Gamberg Consulting, Whitehorse, Yukon Territory) and Dr. Steven J. Bursian (Michigan State University, East Lansing) for kind donation of mink tissues. Assistance by Donna Leggee, Leah Tivoli, Kovana M. Loua, and Stephanie Bailey is greatly appreciated.

Oxidative Stress and Sex Steroid Levels in Fish Following Short-Term Exposure to Pulp-Mill Effluents

This study investigates the relationship between oxidative stress and reproductive dysfunction in wild white sucker (Catostomus commersoni) with short-term exposures to pulp-mill effluent. Hepatic oxidative damage, as quantified using 2-thiobarbituric acid-reactive substances (TBARS), was often increased with effluent exposure within 4–8 d, but responses varied by species, sex, and effluent. Fatty acyl-coenzyme A (CoA) oxidase (FAO) and ethoxyresorufin O-deethylase (EROD) activities were also significantly induced between 4 and 8 d of exposure. There were marked species differences in oxidative stress, as TBARS, FAO, and EROD responses in white sucker differed dramatically from those of longnose sucker (Catostomus catostomus) exposed under identical conditions. Exposure for 8 d to pulp-mill effluent delayed ovulation in white sucker, and these delays were independent of changes in circulating testosterone and 17α,20β-dihydroxy-4-pregnen-3-one titers. Evaluations of the effects of pulp mill effluent on in vivo plasma steroid levels and in vitro steroidogenic capacities were compromised due to caging stress. In vivo preexposure to pulp-mill effluent did not reduce in vitro ovarian follicle steroidogenic capacities when exposed to additional reactive oxygen species (ROS) generators. Endocrine and oxidative stress parameters may be interrelated, as the in vivo administration of ferric nitrilotriacetate (Fe3+NTA) significantly reduced circulating sex steroids. Administration of a superactive GnRH analog containing a dopamine inhibitor significantly increased TBARS within 24 h, indicating endocrine status is capable of modifying oxidative stress responses. This study provides new knowledge regarding the onset of oxidative stress and changes in reproductive endpoints in fish following pulp-mill effluent exposure. The authors gratefully acknowledge the technical assistance of P. Boutot, C. Chisholm, S. Currie, K. Daynes, M. Edwards, M. Gray, E. LeBlanc, L. Luxon, C. Portt, D. Stevens, and G. Tetreault. We thank D. Roy of the Atlantic Salmon Federation for the loan of fish tanks. We thank the anonymous reviewers for their constructive comments, which greatly strengthened the article. This work was supported by Canadian Network of Toxicology Centers (CNTC), Department of Fisheries and Oceans (DFO), Environment Canada, and Natural Sciences and Engineering Research Council (NSERC) of Canada grants to G. Van Der Kraak. K. D. Oakes received financial support from CNTC, DFO, NSERC, and the Ontario Graduate Scholarship program.

48 MORPHOLOGICAL ANOMALIES OF FETAL MEMBRANES DURING GESTATION IN BOVINE CLONES DERIVED BY SOMATIC NUCLEAR TRANSFER

High pregnancy loss and prenatal morbidity and mortality encountered in cloned animals might be explained by placental nutritional or steroidogenic insufficiency that would indirectly compromise fetal survival (Hashizume et al. 2002 Cloning and Stem Cells 4(3), 197-209). Our hypothesis is that ultrasonographic characterization of placenta in bovine clones could be used to predict anomalies in fetal development and well-being during pregnancy. We examined surrogate heifers bearing cloned fetuses (n = 37) and fetuses obtained by traditional embryo transfer (n = 5) in three stages of gestation (Day 70, 100 and 200). Morphological parameters based on direct ultrasonographic observations were collected: thickness and shape of amniotic membrane, utero-placental thickness, placentomes shape and length in fetal area, and umbilical cord shape and appearance. Analysis was done using repeated measures linear model, with day as a repeated factor. Of all clone pregnancies, 30 females were still pregnant at Day 70 and only 16 reached Day 100, from which 63% had different degrees of amniotic and/or umbilical cord anomalies. No placental anomalies or abortions were observed in the control group. The amniotic membrane abnormalities observed at Day 100 were irregularities and presence of nodules (rosary-like) in the cross-sectional view of the membrane. Hyperechogenic spikes or irregularities around the umbilical cord were observed at Day 100 in 38% of the clones (n = 6) and all of them also had amniotic anomalies. From the clone pregnancies with amniotic and/or umbilical cord problems, 30% aborted between Days 100 and 200, and for those that went to term (Days 264-278; n = 7), all calves but one died at birth or during the first month of life. Statistical analysis results showed that placentomes in cloned embryos were larger than those in control embryos (P = 0.003; least-squares mean (LSM) for clone = 4.34 cm, control = 2.97 cm) in all three stages of gestation. During the same period, amniotic membranes of clones became thicker compared to those of the control group (P = 0.0001; LSM for clone = 0.25 cm, control = 0.11 cm). Variation in utero-placental thickness was also observed. At Day 70, the utero-placental layer was thicker in clones in comparison to controls (LSM for clone = 0.32 cm, control = 0.30 cm) before it became thinner at Day 200 (LSM for clone = 0.38 cm, control = 0.40 cm). The present results showed that morphological anomalies of placentomes, amniotic membrane and umbilical cord appear during gestation of bovine cloned fetuses that could potentially compromise normal fetal development. Also, ultrasonographic monitoring of pregnancies of cloned animals is a useful tool to characterize the fetal membrane changes. This work was funded by a Strategic Project Grant from the Natural Sciences and Engineering Research Council (NSERC) Canada.

Drastic Luminescence Response to Carbon Monoxide from a RuII Complex Containing a Hemilabile Phosphane Pyrene Ether This work was supported by the Natural Sciences and Engineering Research Council (NSERC) of Canada. C.W.R. thanks NSERC and UBC for graduate fellowships.

From weak blue to intense blue-green: this change in emission results when [RuCl2(POC4Pyr-P,O)2] reacts with carbon monoxide. The reason is the formation of the dicarbonyl complex shown (see picture), in which CO has replaced the labile coordinating site of the hemilabile ligand POC4Pyr. The increased flexibility in the tethered pyrenyl groups allows the formation of inter- and intramolecular excimers in this complex. POC4Pyr=4-{2-(diphenylphosphanyl)phenoxy}butylpyrene.

Drastic Luminescence Response to Carbon Monoxide from a RuII Complex Containing a Hemilabile Phosphane Pyrene Ether This work was supported by the Natural Sciences and Engineering Research Council (NSERC) of Canada. C.W.R. thanks NSERC and UBC for graduate fellowships.

Von schwach blau zu intensiv blaugrün: Diese Veränderung der Emission ist die Folge der Reaktion von [RuCl2(POC4Pyr-P,O)2] mit Kohlenmonoxid. Der Grund ist die Bildung des gezeigten Dicarbonylkomplexes, in dem CO das labile Koordinationszentrum des hemilabilen Liganden POC4Pyr verdrängt hat. Die höhere Flexibilität der über Spacer gebundenen Pyrenylgruppen ermöglicht die Bildung inter- und intramolekularer Excimere in diesem Komplex. POC4Pyr=4-{2-(Diphenylphosphanyl)phenoxy}butylpyren.

In defense of functional independence: Violations of assumptions underlying the process-dissociation procedure?

Rotman Research Institute of Baycrest Centre,University of TorontoT. Curron and D. L. Hintzman (1995) claim to have shown that the independence assumptionunderlying the process-dissociation procedure (L. L. Jacoby, 1991) is not justified. Theyargued that correlations between processes at the level of items can result in an underestima-tion of automatic processes large enough to produce artifactual dissociations between processestimates. In contrast, the authors show that the effects of extremely high correlations at thelevel of items are likely to be trivial, and not differential across conditions. Curran andHintzman's dissociations probably reflect violations of boundary conditions for use of theprocess-dissociation procedure, rather than violations of independence.It is important to distinguish between automatic andconsciously controlled memory processes. For example,although amnesic patients are often unable to consciouslyremember previously presented words on direct memorytests, such as recall or recognition tests, they use the wordson indirect memory tests, such as stem- or fragment-completion tests, more often than would be expected bychance (Moscovitch, Vriezen, & Gottstein, 1993). Similardissociations are found in people with normally functioningmemory (Roediger & McDermott, 1993). Comparing directand indirect memory tests has significantly advanced ourunderstanding of automatic and controlled processes. How-ever, performance rarely reflects only one process acting inisolation; that is, controlled processes often influence perfor-mance on indirect memory tests (Holender, 1986; Toth,Reingold, & Jacoby, 1994), and automatic processes affectperformance on direct memory tests (Jacoby, Toth, Y Jeffrey P.loth, Rotman Research Institute of Baycrest Centre, University ofToronto, Toronto, Ontario, Canada.Preparation of this article was supported by Natural Sciences andEngineering Research Council Operating Grant OG281 andby National Science Foundation Grant SBR-9596209. We thankC. M. Kelley and B. Spellman for their helpful comments.Correspondence concerning this article should be addressed toLarry L. Jacoby, Department of Psychology, McMaster University,1280 Main Street West, Hamilton, Ontario L8S 4K1, Canada.Electronic mail may be sent via Internet to jacoby @mcmaster.ca.motel). For an inclusion test, subjects were instructed to usethe stem as a cue to recall an old word or, if they could not doso, to complete the stem with the first word that came tomind. An inclusion test is like a standard test of cued recallwith instructions to guess when recollection fails. Subjectscould complete a stem with an old word either because theyrecollected the old word, with a probability of R, or becausethe old word came automatically to mind, with a probabilityof A. If these two bases for responding are independent, theninclusion performance equals R + A - RA. For an exclusiontest, subjects were instructed to use the stem as a cue torecall an old word but not to use recalled words to completethe stems. That is, subjects were told to exclude old wordsand to complete stems only with new words. In thiscondition, subjects would complete a stem with an old wordonly if the word came automatically to mind withoutrecollection of its prior presentation: A{ - R) = A — RA.The difference between the inclusion and exclusion testsprovides an estimate of the probability of recollection.Given that estimate, one can compute the probability of anold word automatically coming to mind: A = Exclusion/(1 — R). When these equations were applied to the data fromJacoby et al., results showed that dividing attention signifi-cantly reduced estimates of recollection (.25 vs. .00) but leftautomatic influences almost invariant (.47 vs. .46). That is,the estimates showed a process dissociation similar to thetask dissociations found between direct and indirect memorytests (Koriat & Feuerstein, 1976; Parkin, Reid, & Russo,1990).Table 1 summarizes results from experiments that haveused the process-dissociation procedure to examine theeffects of attention and of presentation duration on R and A.'

Dolomitization and Neomorphism of Mississippian (Visean) Upper Debolt Formation, Blueberry Field, Northeastern British Columbia: Geologic, Petrologic,  and Chemical Evidence

Petrographic, chemical, and isotopic studies of the Mississippian (Visean) upper Debolt Formation in the Blueberry field, British Columbia, Canada, reveal that dolomitization was the result of several diagenetic events and that neomorphic alteration of these dolomites significantly modified their original chemical signatures. These studies also demonstrate how tectonics play an important role in controlling and modifying reservoir dolomites in the area. Petrographic investigations have documented two early dolomite phases, (1) early matrix dolomite and (2) pervasive dolomite, and two later generations, (3) coarse cement and (4) pseudomorphic replacement of crinoids. Early matrix dolomite occurs as small (average 25 µm) subhedral to euhedral crystals that replace the matrix of carbonate mudstones, wackestones, and packstones. Petrographic evidence suggests that early matrix dolomite had a relatively early, precompaction origin, possibly from marine fluids. However, geochemical evidence indicates that later fluids have altered their original geochemical signatures. ©Copyright 1997. The American Association of Petroleum Geologists. All rights reserved.1Manuscript received February 1, 1996; revised manuscript received August 16, 1996; final acceptance January 19, 1997. 2Department of Earth Sciences, University of Windsor, Windsor, Ontario, Canada N9B 3P4. Present address: Chauvco Resources, Ltd., 2900, 255-5th Avenue S.W., Calgary, Alberta T2P 3G6 Canada. 3Department of Earth Sciences, University of Windsor, Windsor, Ontario, Canada N9B 3P4. This research was supported by individual operating grants from Canada's Natural Sciences and Engineering Research Council (NSERC) awarded to I. S. Al-Aasm and additional funding from PanCanadian Petroleum Resources Limited, and Suncor Inc. S. Durocher acknowledges support from an Ontario Graduate Scholarship. S. Brame (Talisman Energy), L. Williams (Phillips Petroleum Resources, Ltd.), G. Burrowes and I. Mcllreath (PanCanadian Petroleum Ltd.), and J. Packard (Rhomb Carbonate Consulting Ltd.) are thanked for the valuable information, insights, and ideas for tackling the complexities of the Blueberry field. Thanks are also due to J. Veizer (University of Bochum and University of Ottawa) for strontium isotope analysis. An earlier version of this paper benefited from critical reviews by M. Malone (Texas A&M University), C. Viau (Shell Canada, Ltd), S. Schutter, J. Dravis (Dravis Interest Inc.), and an anonymous reviewer.

Research laboratory for fish processing automation

This paper outlines the organization, resources, and research and development activities of a newly established laboratory for industrial automation at a major Canadian university. The laboratory has been established in the Department of Mechanical Engineering primarily to support the research and development activities associated with the Natural Sciences and Engineering Research Council (NSERC) Chair of Industrial Automation. The research is focused on the development of advanced and low-cost technology for flexible automation of the fish processing industry. The main objective is to upgrade the technology used in the mechanical processing of fish, thereby reducing wastage of the primary product, improving efficiency, and making the local industry more competitive in export markets. Establishment of an infrastructure in industrial automation within the university and local training/ retraining of engineers with control and automation expertise for local industries are related objectives. As a specific task, an experimental workcell for fish processing is being developed in the laboratory. The theme of the activities of the laboratory is the integration of advanced control, high-level computer vision, and robotic manipulation and devices, for application in the area of fish processing.

Canadian Council on Animal Care: Its Role

Every year in Canada about 2,000,000 animals are used in research (85.5 percent), mandatory testing (9.5 percent), and education (4.7 percent). Ninety percent of these are rats, mice, fish, and fowl. Surveillance over the use of experimental animals, including wild vertebrates and invertebrates such as octopi and squid, is the responsibility of the Canadian Council on Animal Care (CCAC), a national, voluntary peer-review organization, founded in Ottawa in 1968. Funded by Canada's two major granting agencies, the Medical Research Council (MRC) and the Natural Sciences and Engineering Research Council (NSERC), the CCAC comprises 20 member organizations from academia, government, industry, laboratory animal science, and the animal welfare movement. Assessment Visits Both scientists and animal welfare advocates are included on CCAC panels, which assess every three years (or more often if needed) Canada's universities and community colleges, government laboratories, and commercial laboratories. The evaluations are based on CCAC's Guide to the Care and Use of Experimental Animals, volumes 1 and 2 (1980, 1984), and supporting monographs. Institutions that continue to fail to comply with CCAC requirements face loss of funding from the MRC and NSERC. Since this policy was published in 1985, those found in noncompliance have actively addressed CCAC's concerns, and it has not yet been necessary to withdraw grants. The imposition of Noncompliance Status is the responsibility of the CCAC as a whole, acting on the recommendations of the assessment panels. It should be noted that where the health of the animals is involved, an assessment panel has the authority to order the animals immediately relocated and to close the facility until it can be brought up to CCAC standards. This rather drastic measure has been necessary only a handful of times. There has been, however, a difficulty in perception on the part of some in the animal welfare movement who have asked: If this institution has been declared in Con

Static and dynamic stability criteria during free diffusion in a ternary system

Acknowledgment. The continuous financial support of the Natural Sciences and Engineering Research Council (NSERC) Strategic Grant Program of Canada is gratefully acknowledged. The ground state for CH3LiH shows the species to be comprised of two weakly interacting Parts, a methyl and lithium hydride. The higher excited 2E states show greater interaction of these two parts but with less C-H bonding. Registry No. Li, 7439-93-2; CH4, 74-82-8; CH,LiH, 89922-1 8-9; The pathway to insertion appears to be by an abstraction process CH3, 2229-07-4; LiH, 7580-67-8.

Peer review and national need

In this paper a quantitative look is taken at some of the latent conflicts between the Canadian government's changing expectations of university research and the peer review process by which the Natural Sciences and Engineering Research Council (NSERC), the major funder of scientific research in the universities, allocates its resources. Focusing on the granting histories of individual grantees, it is shown that, statistically, an individual's funding level is a function of the period of time over which he has been funded by the Council. Studies of other systems of decision making make these findings unsurprising in that they reflect the incremental outcomes of group decisions. However, the do point to the structural problems inherent in a top-down approach to stimulating research in areas of national need within a system involving diffuse focal points for decision making. If future government funding is to be ensured, it will be important to either clarify expectations in order to take account of the traditional autonomy of research councils or, if need is to be explicitly defined as customer oriented, to explore alternative funding mechanisms.

A portrait of the substrate for self-stimulation.

Quantitative properties of the neural system mediating the rewarding and priming effects of medial forebrain bundle (MFB) stimulation in the rat have been determined by experiments that trade one parameter of the electrical stimulus against another. The first-order neurons in this substrate are for the most part long, thin, myelinated axons, coursing in the MFB and ventral tegmentum, with absolute refractory periods in the range .5-1.2 msec and conduction velocities of 2-8 m/sec. Local potentials in these axons decay with a time constant of about .1 msec. A supernormal period follows the recovery from refractoriness. These axons integrate current over exceptionally long intervals, accommodate slowly, and fire on the break of prolonged anodal pulses. These properties rule out the hypothesis that catecholamine pathways constitute the first-order axons. The second-order (postsynaptic) part of the substrate shows surprisingly simple spatial and temporal integrating characteristics. We examine the logic that permits conclusions of this sort to be derived from behavioral data and the role of these derivations in establishing neurobehavioral linkage hypotheses. In this article we describe properties of the neural tissue whose excitation eventuates in the reinforcing and motivating effects of electrical stimulation of the medial forebrain bundle (MFB) in the rat. The goal of the research is to identify these systems by anatomical and electrophysiological methods, thus providing physiological psychology with a model for studying the neurophysiological bases of learning and motivation in a higher vertebrate. The properties of the substrate for selfstimulation described in this article have been inferred from behavioral trade-off experiments—experiments that determine the The authors are listed in alphabetical order. They gratefully acknowledge the following grant support: National Science Foundation Grant BMS-16339 to C. Gallistel; National Institute of Health Grant NS-14935 to C. Gallistel, P. Hand, & M. Reivich; National Institute of Health Training Grant MH15092 (A. Epstein & C. Gallistel, codirectors); Natural Science and Engineering Research Council (NSERC) of Canada Grant A0308 and Quebec Formation des Chercheurs et les Actions Concert6es (FCAC) Grant EQ-09 to P. Shizgal; and NSERC of Canada Grant A7077 to J. Yeomans. Requests for reprints should be sent to C. R. Gallistel,