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The emerald ash borer, Agrilus planipennis Fairmaire (Coleoptera: Buprestidae), is a serious pest of ash (Fraxinus spp.) (Oleaceae) in North America. Control of emerald ash borer is difficult in natural forest settings; therefore, a classical biological control programme is the most feasible management option for this invasive, nonnative insect. Here, we report the first Canadian release and establishment of parasitoids Tetrastichus planipennisi Yang (Hymeoptera: Eulophinae), Oobius agrili Zhang and Huang (Hymenoptera: Encyrtidae), and Spathius galinae Belokobylskij and Strazanac (Hymenoptera: Braconidae) in natural forests in Ontario, Quebec, and New Brunswick, Canada for the control of emerald ash borer. Releases of T. planipennisi were made from 2013 to 2019, O. agrili from 2015 to 2019, and S. galinae from 2017 to 2019. Trees from release sites were destructively sampled to rear out adult emerald ash borers and parasitoids 1–3 years after parasitoid release. Recoveries of T. planipennisi were made at 81% of release sites (13 of 16) 1–2 years after release, and O. agili were recovered from 29% of release sites (4 of 14) 1–3 years after release. Spathius galinae was not recovered. These data provide important information for the development and deployment of a successful biological control programme for the management of emerald ash borer in Canada.

The role of topical non-steroidal anti-inflammatory drugs (NSAIDs) in routine cataract surgery has been established since decades. Topical NSAIDs have been shown to reduce postoperative ocular inflammation and pain, preserve intraoperative mydriasis, and reduce the risk of postoperative cystoid macular oedema, whilst carrying a very low side-effect profile. Nepafenac is one of the currently available topical NSAIDs. The studies have shown that is has a high ocular penetration, allowing for potentially better results than other NSAIDs. This review gathers the current literature on the role of nepafenac in cataract surgery aiming to help surgeons maximise the benefits of its use to achieve improved surgical outcomes.

Laboratory insect colonies are an essential part of experimental insect science. Formalized naming of laboratory stocks is standard practice in model organisms such as mice and fruit flies, but crucial details such as colony origin and standard names are often lacking in nonmodel systems. For institutions involved in rearing multiple nonmodel species, effective monitoring requires standardized naming and nomenclature, from establishment to production, distribution, and publication. Insect rearing has been the cornerstone of the Insect Production and Quarantine Laboratories (IPQL) at the Great Lakes Forestry Centre for over 70 yr, but the histories of the insect colonies in this facility have not been adequately documented and formal, standardized names do not exist. We propose a standardized naming framework that we applied to the eight species reared at the IPQL to rectify these deficiencies. We also present the origin and history of each colony, essential information that is challenging to obtain post hoc. We suggest that other research institutions consider developing similar standards, so they can accurately document, communicate, and track laboratory insect their within the facilities and through the scientific literature.

The spruce budworm, Choristoneura fumiferana (Clem.), has an obligatory winter dormancy period that lasts up to 10 months in the field. In the Great Lakes Forestry Centre rearing facility, neonate larvae spin hibernacula in cheesecloth, which is then stored at 2 °C for between 20 and 30 weeks. Although dormancy survival and synchrony of postemergence development are highest when larvae are stored in the cold for 16–35 weeks, it is not known how cold-storage duration affects spruce budworm performance once diapause has been completed. We exposed approximately 9250 second-instar larvae (belonging to three rearing cohorts) to 2 °C for 16, 19, 22, 25, 28, 31, 34, or 37 weeks and monitored various postdiapause performance variables. Increasing cold storage from 16 to 25 weeks or more resulted in small (approximately 10%) increases in dormancy survival and larval development rates (from second instar to pupation), a larger (up to 23%) increase in pupal mass and realized fecundity (number of eggs laid per female), and an increase of at least 25% in late-instar survival (from fifth instar to pupation). The only variable that was negatively affected was the pupal survival, but the decrease was relatively small. Therefore, storing diapausing larvae for at least 25 weeks optimizes postdiapause performance variables that are important for mass-rearing efficiency.

A droplet-imbibing assay was used to assess the susceptibility of third-instar larvae of the spruce budworm, Choristoneura fumiferana Clemens, to Foray 48B, a commercial formulation of Bacillus thuringiensis subsp. kurstaki containing 12.7 billion international units (IU) per litre. We observed an LD50 of 1.17 IU/larva for third instars, as compared with 3.96 IU/larva for fifth instars. Comparison with previously published data on susceptibility of later instars revealed that third instars were two-to three-fold more susceptible to Foray 48B than fourth and fifth instars and about eightfold more susceptible than sixth instars. Vulnerability of third instars to simulated aerial spray deposits was investigated by using potted balsam firs, Abies balsamea L. Potted trees were infested in the greenhouse when the buds were starting to swell, using a density of about one newly emerged second-instar larva per bud. When 90% of the larvae had reached the third instar and 52% of the buds were breaking (4 d after infesting), infested twigs were harvested and sprayed with undiluted Foray 48B in a spray chamber. Spray droplets on the buds measured between 25 and 125 μm in diameter, with 80% having a diameter of 80 μm or less. A density of 4.2 ± 1.0 droplets per bud resulted in spruce budworm mortality of 83.4 ± 4.0% and a corresponding reduction in larval density of 86.5 ± 3.9% (means ± SD, n = 6) after 5 d at 25 °C. Results of the spray chamber test suggest that third-instar spruce budworms were able to acquire a lethal dose, despite their concealed feeding habits.

Une population de larves de la Tordeuse des bourgeons de l'epinette, Choristoneura fumiferana (Clemens), a ete suivie pendant 5 jours apres arrosage d'une preparation commerciale de Bacillus thuringienesis Berliner ssp. kurstaki afin de determiner la fraction de la dose qui a ete absorbee et ses effets (mortalite, recuperation, alimentation et croissance) en relation avec la quantite de la preparation qui s'est deposee au sol et la persistance de ces residus. Le but ultime de l'exercice etait de verifier si les observations anterieures en laboratoire des effets de B. thuringiensis sur l'alimentation et sur l'ingestion du bacille se produisent aussi sur le terrain. Environ 40% des larves traitees ont ingere une dose letale en moins d'une journee. Les larves qui ont ingurgite une dose letale ont ete transferees du feuillage traite a un regime artificiel (non traite) mais elles sont mortes sans chercher a se nourrir de nouveau. Le retour a l'alimentation chez les larves qui ont survecu au traitement s'est fait tardivement par rapport a la population temoin durant les 3 jours qui ont suivi l'arrosage; pendant ce temps, l'activite alimentaire normale et l'augmentation de la masse etaient inhibees. L'alimentation ainsi inhibee chez les larves survivantes semble les avoir empechees d'ingurgiter davantage du produit puisque la proportion de larves tuees n'a pas augmente dans les recoles quotidiennes, en depit de la presence de residus importants du produit aux sites d'alimentation des larves. Le retour a un temps « normal » de recuperation le 4 e jour coincidait avec une reduction de 65-85% de la persistance du pathogene sur le feuillage et nous n'avons pas observe de nouvelle phase d'absorption letale a partir du moment ou la mortalite reliee au traitement est baissee a environ 20% le 4 e et le 5 e jours. Ces observations sont comparables aux resultat obtenus en laboratoire sur les effets de B. thuringiensis sur l'alimentation des larves et sont conformes a l'hypothese selon laquelle l'inhibition de l'alimentation peut empecher l'absorption d'une dose letale.

Exposing larvae of the spruce budworm, Choristoneura fumiferana (Clemens), to sublethal (< 50% lethal dose) levels of Bacillus thuringiensis subsp. kurstaki at various stages of their development significantly increased development time to the pupal stage and reduced pupal size and number of eggs laid per female, but did not affect the proportion of embryonated eggs. The changes in larval development time, pupal weight and fecundity depended on the larval stage that was treated. Exposure of fourth instars delayed larval development and reduced only male pupal weights with no effects on fecundity. Exposure of sixth instars delayed larval development to a lesser extent than exposure of fourth instars but had a pronounced effect on weight of both male and female pupae. The effect on pupal weight was sex dependent, as males tended to be more affected than females. The reduction in male pupal weight did not appear to influence fecundity, because the effect of exposure was explained by the change in female pupal weight. Effects on larval growth and pupal weight were proportional to the dose that was ingested during exposure, and were observed at doses as low as one-tenth of the LD 50 . Ingestion of an LD 50 caused a 29 or 45% delay in development of, respectively, female or male larvae when exposed as fourth instars and a 30% reduction in female pupal weight when larvae were exposed as sixth instars.

We modified a neonate droplet-feeding technique to investigate lethal dose requirements for the spruce budworm, Choristoneura fumiferana (Clemens), without the confounding influence of instar-specific feeding rates and feeding behavior. Individual 4th, 5th, and 6th instars consumed known doses of 3 commercial Bacillus thuringiensis variety kurstaki products suspended in a buffer containing sucrose. The droplet volume was adjusted for each instar to ensure complete uptake. Experiments with 32p indicated that 98-99% of the presented volume was taken up during imbibing and that 89-98% of this was actually ingested. The LD50s expressed in international units per larva ranged from 1.6 to 1.8 for 4th, 2.2 to 2.9 for 5th, and 5.1 to 7.5 for 6th instars. The decrease in larval susceptibility in later instars was not caused by an increase in larval weight; on a per unit weight basis, 6th instars were 4.5- fold more susceptible than 4th instars (0.32 versus 1.44 IU/mg fresh weight). The relationships between larval stage and susceptibility was the same for Dipel 48AF, Foray 48B, and Foray 76B. Droplet sizes that are theoretically required to deliver a lethal dose in the form of 1 droplet per spruce needle ranged from 55 to 96 µm for an LD50 and from 129 to 192 µm for an LD95, depending on instar and potency of the product. These calculations suggest that droplets in the size range that is most commonly encountered on coniferous foliage after aerial application contain at best little more than an LD50.

Geographic variation in susceptibility to the pathogen Bacillus thuringiensis Berliner ssp. kurstaki was assessed among five populations of the spruce budworm, Choristoneura fumiferana (Clemens), across Canada. Larvae or pupae were collected from Prince Edward Island, northern New Brunswick, central Ontario, northeastern Alberta, and northeastern British Columbia. The response of field populations to the 1980 industrial standard of the HD-1 strain of the pathogen was compared with the concurrent response of a laboratory colony as an internal standard. Equal slopes of the probit regression lines indicated homogeneity of variation in susceptibility among populations. LC50values ranged from 2.6 international units (IU) per sixth-instar larva for the most susceptible population to 8.3 IU per larva for the least susceptible. Although significant, the variation in population susceptibility was within the range of variation that is commonly observed among repeated bioassays against cohorts of a single population. We conclude that variation in susceptibility to B. thuringiensis among spruce budworm populations is low. The data provide a basis for monitoring changes in susceptibility of spruce budworm populations in response to increased use of this pathogen in forest-protection programs.

A process-oriented model was recently developed to simulate the efficacy of spray products containing Bacillus thuringiensis Berliner subsp. kurstaki (Bacillaceae) against the spruce budworm, Choristoneura fumiferana Clemens (Cooke and Régnière 1996). The model accurately predicted foliage protection and larval population reduction during validation spray trials (Régnière and Cooke 1998; Cooke and Régnière 1999). The impact of treatment on budworm generation survival was generally well mimicked by the model except for a consistent overestimation of survival at the end of immature development in the treated plots. Régnière and Cooke (1998) speculated that residual mortality due to treatment may be occurring during the pupal stage. Carry-over of B. thuringiensis from larvae to pupae has been documented for spruce budworm (Klein and Lewis 1966) and several other Lepidoptera (Legner and Oatman 1962; Angus 1965). Although we recently investigated the response of spruce budworm larvae to ingestion of sublethal doses of B. thuringiensis (Pedersen et al. 1997), effects on pupal survival or adult emergence were not examined. In this note, we report the results of an experiment designed to assess such effects.

MoNET TM (Media over Net) SX000 product family is designed using a scalable voice, video and packet-processing platform to address applications with channel densities from few voice channels to four OC3 per card. This platform is developed for bridging public circuit-switched network to the next generation packet telephony and data network. The platform consists of a DSP farm, RISC processors and interface modules. DSP farm is required to execute voice compression, image compression and line echo cancellation algorithms for large number of voice, video, fax, and modem or data channels. RISC CPUs are used for performing various packetizations based on RTP, UDP/IP and ATM encapsulations. In addition, RISC CPUs also participate in the DSP farm load management and communication with the host and other MoP devices. The MoNET TM S1000 communications device is designed for voice processing and for bridging TDM to ATM and IP packet networks. The S1000 consists of the “DSP farm” based on Carmel DSP core and 32-bit RISC CPU, along with Ethernet, Utopia, PCI, and TDM interfaces. In this paper, we will describe the VoIP infrastructure, building blocks of the S500, S1000 and S3000 devices, algorithms executed on these device and associated channel densities, detailed DSP architecture, memory architecture, data flow and scheduling. Key words: Gateway, VoIP, VoATM, IP Phone