ALBERT

Notes: The Devonian of East Greenland comprises a thick sequence of continental clastic sediments infilling an extensional basin. West of the main basin bounding fault (Western Fault Zone) are scattered outliers of Devonian conglomerate which accumulated in small basins such as found on the island, Ella Ø. The Ella Ø Basin formed by extensional movement along the Narhval Sund Fault accompanied by the formation of a prominent bedding parallel detachment surface which was subsequently modified by sub-aerial exposure to become the unconformity surface. Mapping of this unconformity surface shows major vertical relief. A thick sequence of conglomerate occurs on Ella Ø, which, close to its exposed basal unconformity, has three lacustrine beds intercalated within it. Detailed analysis of one lake unit shows it to have significant lateral variation. At proximal localities it largely comprises lacustrine turbidites, whereas more distal locations were within a stratified lake. The interpreted sequence of events on Ella Ø is an interval of fluvial sedimentation followed by rapid drowning of the topography with lacustrine sediments onlapping onto basement. After an interval of deeper lacustrine sedimentation including laminites, the lake shallowed, the lithology changed to limestone and the lake dried out. Conglomerate deposition then recommenced. Maximum lake water depth of 100 m is estimated following correction (7°) for post-Devonian rotation, both determined using the distribution of lacustrine sediments on the unconformity surface. The preferred mechanism for flooding of the Ella Ø Basin is episodic flooding of the entire basin system. Lacustrine sediment preservation results purely from its deposition amongst topography at the edge of the active fluvial system. In such fluvial systems lacustrine sediments may be part of the normal sedimentary cycle but were almost always removed by reworking.

Notes: Laboratory studies have shown that the amounts of glutathione (GSH) and cysteine are higher in grass species that are moderately tolerant, such as wheat (Triticum aestivum L., cv. Fredrick), and moderately susceptible, such as barley (Hor deum vitlgare L., cv. Legér) and triticale (cv. OAC Trillium), to fenoxaprop-ethyl (FE) than in species that are very susceptible to the her bicide, such as oat (Avena saliva L., cv. OAC Woodstock), wild oat (Avena fatua L.), yellow foxtail (Setaria glanca (L.) Bcauv.), large crab grass (Digitaria sanguinalis (L.) Scop.) and bar nyard grass (Echinochloa crus-galli (L.) P.B.). The safener, fenchlorazole-ethyl (FCE) was found to increase and decrease, respectively, the amounts of GSH and cysteine in the moderately tolerant and moderately susceptible species but had no effect on the susceptible species. It is sug gested that in the moderately tolerant and moderately susceptible species, especially following FCE treatment, more GSH is available to detoxify the herbicide. Glutathione-S-tranferase activity (GST) for FE was found to be very low in all of the species tested. In vitro experiments at physio-logical pH. demonstrated that FE may conjugate with GSH nonenzymatically. Therefore, it is suggested that nonenzymatic conjugation of fenoxaprop-ethyl with glutathione may be an important mechanism for tolerance of some grasses to this herbicide.

Notes: The effect of five herbicide safeners on preventing maize (Zea mays L.) injury by acetochlor [N-(2-ethyl-6-methyl-phenyl)-N-(ethoxymethyl)-chloroacetamide], their influence on herbicide uptake and metabolism to a glutathione (GSH) conjugate as well as on GSH content and glutathione S-transferase activity (GST) in untreated and herbicide with/without safener-pre-treated 4-day-old seedlings were determined. The safeners studied were: AD-67 (N-di-chloroacetyl-1-oxa-4-azaspiro-4-5-decane), BAS-145138 [1-dichloroacetyl-hexahydro-3,3,8a-trimethyl-pyrrolo(l,2-a)pyrimidin-6(2H)-one], dichlormid (N, A,-diallyl-2,2-dichlo-roacetamide), DKA-24 (N, N2-diallyl-N2dichloroacetylglycineamide) and MG-191 (2-dichloromethyl-2-methyl-1,3-dioxolane). All safeners significantly increased [14C]acetochlor uptake and metabolism rate, maize GSH content and GST activity. Seedlings receiving BAS-145138 pre-treatment metabolized almost 70% of the absorbed [14C]acetochlor within 10 min.Safener-enhanced GST activity was always found to be higher when [14C]acetochlor was used as the substrate compared with CDNB (1-chloro-2,4-dinitrobenzene). Although DKA-24 had a significantly lower influence on both herbicide metabolism and GST activity, it was nearly as effective a safener as BAS-145138, while the others provided no or poor protection to maize from acetochlor injury when they were not incorporated in the soil. Effets d'antidotes sur la toxicité, la pénétration et le métabolisme de I'acétochlore chez le mats etsur l'activité glutathion S-transférase Cinq antidotes d'herbicides diminuaient la toxicité de 1'acétochlore [N-(2-éthyl-6-méthyl-phényl)-N-(éthoxyméthyl)-chloroacétamide] à I'égard du maïs (Zea mays L.). Lew effet sur l'absorption de l'herbicide et sur son métabolisme en un conjugué avec le glutathion (GSH), de même que leur effet sur la teneur en GSH et 1'activité glutathion 5-transférase (GST) ont étéétudiés sur des maïs âgés de 4 jours. Les antidotes étaient: l'AD-67 (N-dichloroacétyl-1-oxa-4-azaspiro-4,5-décane), le BAS-145138 [1 -dichloroacétyl-hexahydro-3,3,8a-triméthyl-pyrrolo(l,2-a) pyrimidine-6(2H)-one], le di-chlormide (N, N-diallyl-2,2-dichloracétamide), le DKA-24 (N, N2-diallyl-N2-dichloracétylgly-cineamide] et le MG-191 (2-dichlorométhyl-2-méthyl-l,3-dioxolane). Tous les antidotes augmentaient de manière significative 1'absorption et le métabolisme de I'acétochlore 14C, ainsi que la teneur du maïs en GSH et son activité GST. Les jeunes plantes prétraitées avec le BAS-145138 métabolisaient en 10 min près de 70% de I'acétochlore 14C absorbé. L'activité GST stimulée par 1'antidote était toujours plus élevée avec I'acétochlore 14C comme substrat qu'avec le CDNB (1-chloro-2,4-dinitrobenzène).Le DKA-24 avait un effet significativement plus faible que le BAS-145138 sur le métabolisme de l'herbicide et sur l'activité GSH, mais son action antidote était presque aussi importante. Les autres produits n'apportaient au maïs qu'une protection faible ou nulle contre l'acétochlore quand ils n'étaient pas incorporés au sol. Wirkung von Safenern auf die Phytotoxizität, Aufnahme und Metabolismus von Acetochlor und die Glutathion-S-Transferase-Aktivität in Mais Die Wirkung von 5 Safenern (AD-67, BAS-145138, Dichlormid, DKA-24 und MG-191; chemische Bezeichnungen s.o.) auf die Phytotoxizität von Acetochlor für Mais (Zea mays L.) und ihr Einfluß auf die Aufnahme des Herbizids und Metabolismus zu einem Glutathion-(GSH-) Konjugat und auf die Glutathion-S-Transferase-(GST-)Aktivität wurde an 4 Tage alten Keimpflanzen untersucht. Durch die Vorbehandlung mit den Safenern wurden die [14C]-Acetochlor-Aufnahme- und -Metabolierungsrate, der GSH-Gehalt und die GST-Ak-tivität signifikant erhöht. Mit BAS-145138 vorbehandelte Keimpflanzen metabolisierten fast 70% des absorbierten [14C]-Acetochlor innerhalb von 10 min. Die durch die Safener erhöhte GST-Aktivität bei [14C]-Acetochlor als Substrat war im Vergleich zu Chlordinitroben-zen immer höher. Obwohl DKA-24 einen signifikant geringeren Einfluß sowohl auf den Herbizidmetabolismus als auch auf die GST-Aktivität hatte, war es fast so wirkungsvoll wie BAS-145138, während die anderen ohne Einarbeitung in den Boden für den Mais keinen oder geringen Schutz gegen Schäden durch Acetochlor boten.

Notes: The spatial structure of several exploited species within and among known populations of the Northwest Atlantic is reviewed using past and current knowledge. For each species, the coherence of existing management units with the spatial scale of population dynamics (populations, sub-populations, and spawning components) is summarized. The implications of this match or mismatch of spatial scales in the maintenance of biodiversity within and among populations are also discussed.

Notes: The ratios of stable isotopes 18O/16O and 13C/12C, in sagittal otolith carbonate from two tropical demersal teleosts, red emperor Lutjanus sebae and Rankin cod Epinephelis multinotatus, from several locations in northern Western Australia, differed between sites. On a broad scale, fish from the four locations, Shark Bay, Ningaloo, Pilbara, and Broome had stable isotope values that were sufficiently different to indicate separate stocks, and it is appropriate to manage these populations of the two species independently in these areas. On a smaller scale, there may be limited mixing of these species between the Pilbara trawl fishery and the trap and line fisheries operating out of Onslow and Broome. Values of stable oxygen isotopes were strongly related to sea surface temperature, although there were some sites in shallow water where low values of stable oxygen isotopes indicated that fish were living in warm water. The use of stable oxygen and carbon isotope values is a valuable, cost effective method of determining the degree of mixing of fish stocks.

Notes: Analysis of nine tetranucleotide microsatellite loci for Atlantic herring at five locations in the Northwest Atlantic including the Bras d'Or Lakes shows considerable genetic variation and significant population structure within the Coastal Nova Scotia management component, and among coastal populations and herring collected from Georges Bank. However, results are also consistent with gene flow across the Gulf of Maine. The magnitude of differentiation between the Bras d'Or Lakes sample and all others considered was sufficient to warrant further investigation. These data support the precautionary spawning-ground based management approach implemented in this area.

Notes: An organism diversity index for use with mixed liquor or wastewater samples was developed to assess the species richness and diversity of activated sludge. The index was used in several studies and was found to be fast and simple to perform using basic laboratory equipment. Two bench-scale and two pilot-scale studies found that the resulting ‘organism diversity index’value was a good indicator of process performance and was not influenced by the total concentration of the mixed-liquor suspended solids but by their nature alone. The technique rapidly yielded pertinent information about the health of the sludge and could be used instead of genetic investigations to obtain population information quickly enough for wastewater-treatment plant process control.

Notes: Increasing restrictions on sewage sludge disposal routes and the tightening of treatment requirements have led to an escalation of sludge-disposal costs which are out of proportion to other sewage-treatment costs: consequently reducing sludge volume is becoming increasingly cost-effective. Consolidation of anaerobically digested sludge has traditionally been difficult and takes many weeks in secondary digesters or deep storage tanks. Pre-aeration of the sludge using the Aercon process can enable consolidation to take place in days instead of weeks.This paper reports the results of a pilot-scale plant designed to investigate further the mechanism by which aeration speeds up consolidation. It was concluded that the rate of consolidation depended on aeration intensity and cooling of the sludge. Inhibition of anaerobiosis was more important than gas stripping in enhancing consolidation.

Notes: Many interesting inverse problems in geophysics are non-linear and multimodal. Parametrization of these problems leads to an objective function, or measure of agreement between data and model predictions, that has a complex topography with many local minima. Optimization algorithms that rely on local gradients in the objective function or that search the model space locally may become trapped in these local minima. By combining simulated annealing with the downhill simplex method, a hybrid global search algorithm is presented in this paper for non-linear, multimodal, inverse problems. The hybrid algorithm shares the advantages of both local search methods that perform well if the local model is suitable, and global methods that are able to explore efficiently the full model space. The hybrid algorithm also utilizes a larger and more complex memory to store information on the objective function than simulated annealing algorithms. The effectiveness of this new scheme is evaluated in three problems: minimization of the multidimensional Rosenbrock function, non-linear, 1-D, acoustic waveform inversion, and residual statics. The performance of the hybrid algorithm is compared with simulated annealing and genetic algorithms and is shown to converge more rapidly and to have a higher success rate of locating the global minimum for the cases investigated.

Notes: A simplified model of domain rearrangement in multidomain particles following the application of an alternating (AF) or direct (DF) field is used to quantify the dependence of anisotropy of magnetic susceptibility on magnetic history. To be able to account for changes in the average susceptibility (i.e. The average of three mutually perpendicular susceptibility measurements) of the sample following field treatment, the model has to be refined by introducing interaction between domains. By fitting theoretical curves of anisotropy versus peak AF to experimental results for samples containing different size fractions of magnetite particles, of average grain size ranging from 0.7 to 58 μm, four relevant parameters can be computed (for each sample), which enables a good fit to be obtained. By allowing two of these parameters to change systematically when a DF is applied (and an IRM is acquired), the anisotropy dependence on direct field strength can also be modelled. This includes the sign change observed as the field-impressed ellipsoid changes from prolate to oblate, together with increases in the average susceptibility as the field increases. However, some details, such as discrepancies between predicted and actual increases in the average susceptibility at high fields, suggest that further refinement of the model is required.