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BACKGROUND A strain of Helicoverpa armigera with 171‐fold resistance to indoxacarb was introgressed with a susceptible strain by serial backcrossing and reselection with indoxacarb resulting in the creation of the near‐isogenic GY7‐39BC4 strain. Fitness was compared on artificial diet under diapause and non‐diapause conditions in resistant, susceptible and F1 progeny from a reciprocal backcross of the two strains using life history trait analyses. Selection experiments were used to determine stability of resistance. RESULTS: There were no significant differences between strains in survival, female fertility or realized fecundity. A comparison of the intrinsic rate of population increase showed similar relative fitness between strains. Lower male fertility and male longevity in the resistant strain and one of the F1 strains compared with the susceptible strain suggests small non‐recessive costs may be associated with male reproductive capacity in individuals with indoxacarb resistance alleles. However, there was no significant decline in resistance in the GY7‐39 strain when reared in the absence of insecticide for five generations. Following an artificially induced diapause, survival was reduced by 52% and pupal weights were significantly lower in the resistant strain compared with the susceptible strain. CONCLUSIONS: These results suggest indoxacarb resistance does not confer a major fitness cost under standard laboratory conditions. However, a survival cost associated with overwintering highlights the imperative for adoption of management strategies in northern regions of Australia where a winter diapause does not occur. © 2020 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Background: Recurrent respiratory papillomatosis is a rare but morbid disease caused by human papillomavirus (HPV) types 6 and 11. Infection is preventable through HPV vaccination. Following an extensive quadrivalent HPV vaccination program (females 12-26 years in 2007-2009) in Australia, we established a method to monitor incidence and demographics of juvenile-onset recurrent respiratory papillomatosis (JORRP) cases.Methods: The Australian Paediatric Surveillance Unit undertakes surveillance of rare pediatric diseases by contacting practitioners monthly. We enrolled pediatric otorhinolaryngologists and offered HPV typing. We report findings for 5 years to end 2016.Results: The average annual incidence rate was 0.07 per 100000. The largest number of cases was reported in the first year, with decreasing annual frequency thereafter. Rates declined from 0.16 per 100000 in 2012 to 0.02 per 100000 in 2016 (P = .034). Among the 15 incident cases (60% male), no mothers were vaccinated prepregnancy, 20% had maternal history of genital warts, and 60% were first born; 13/15 were born vaginally. Genotyped cases were HPV-6 (n = 4) or HPV-11 (n = 3).Conclusion: To our knowledge, this is the first report internationally documenting decline in JORRP incidence in children following a quadrivalent HPV vaccination program. [ABSTRACT FROM AUTHOR]

The principle in Suttor v Gundowda Pty Ltd (1950) 81 CLR 418 provides for an essentially uniform construction of contractual provisions which are intended to bring about an automatic or self-executing termination of a contract, upon the happening of an event that may be caused by the default of one or both of the parties. This article argues that the principle in Suttor should be reevaluated on the basis that it is not well adapted to achieve the policy goals which underpin it. In its place, the courts should directly apply the rule or presumption that a party may not take advantage of their own wrong. [ABSTRACT FROM AUTHOR]

Parasitism of adult Heteronyx dimidiata (Erichson) and H. crinitus Blackburn (Scarabaeidae: Melolonthinae), that attack Eucalyptus nitens plantation seedlings in southern Australia, was recorded over 3 years. An undescribed genus of Blondeliini (Tachinidae: Exoristinae) was reared from both scarab species while a Palpostoma sp. (Tachiinae) was reared from H. crinitus. Flies were observed parasitising flying beetles by intercepting them mid-air. Eggs were laid externally on the exoskeleton, mainly on the dorsum of abdominal tergites. Male H. dimidiata were parasitised significantly more (40%) than female conspecifics (13%) and male or female H. crinitus (both 13%), which was attributed to their greater flight activity searching for mates. Superparasitism was common in both species, particularly in male H. dimidiata (56%of parasitised beetles, up to 22 eggs/beetle), despite evidence that only a single tachinid could complete development in a beetle. Early stages of parasitism in H. dimidiata females did not appear to affect ovarian development nor the ability of beetles to feed on young trees. However, we infer that the tachinids had a significant impact on Heteronyx spp. populations through a reduction in adult beetle longevity and fitness. [ABSTRACT FROM AUTHOR]

Chaetophthalmus dorsalis is a common larval parasitoid of several economically important species of Noctuidae in Australia but little is known about its biology. This paper describes aspects of the behaviour and development of C. dorsalis parasitising Helicoverpa armigera and H. punctigera larvae in the laboratory. At 25°C, C. dorsalis laid a mean of 577 ovolarviparous eggs, 8-9 days after emergence. Parasitoids were able to complete development when newly emerged planidia were placed on all host instars except first instars. Planidia manually placed on the dorsum of the first thoracic segment of host larvae showed no preference to penetrate segments immediately behind the head capsule where they could not be removed by the host. Planidia were significantly faster at penetrating the cuticle of early- (second to fourth) instar compared with late- (fifth and sixth) instar larvae, and late-instar H. punctigera larvae compared with equivalent instars of H. armigera. Parasitoid larval development was significantly faster when planidia were placed on late-instar H. punctigera larvae than on early-instar larvae but puparium development and puparium weight were not affected by host age. Parasitised Helicoverpa larvae gained weight at the same rate as unparasitised larvae until 2-3 days before the exit of C. dorsalis larvae when they entered a premature prepupal phase. Developmental thresholds and day-degree requirements for C. dorsalis were calculated and compared with H. armigera. A new host record for C. dorsalis reared from Neocleptria punctifera (Noctuidae) larvae is given. [ABSTRACT FROM AUTHOR]

Abstract The sex pheromone of Mnesampela privata, an endemic pest of Eucalyptus plantations in Australia, was previously identified as a single bioactive compound, (3Z,6Z,9Z)-3,6,9-nonadecatriene (C19 triene). Initial field testing of lures containing 1 mg, 5 mg or 10 mg of C19 triene (>98% purity) caught no or very few male M. privata. (3Z,6Z,9Z)-3,6,9-Henicosatriene (C21 triene) was identified as an additional minor pheromone component in abdominal tip extracts of M. privata females from Tasmania. Levels of both compounds extracted from individual females varied greatly, but the ratio was relatively constant at 33:1 C19:C21 trienes. Electroantennograms (EAG) of synthetic C21 triene with male M. privata gave positive but consistently lower responses than elicited by the C19 triene. Field tests showed that the addition of 1-6% C21 triene to 1 mg C19 triene significantly increased trap catch and the detection of M. privata in plantations. Traps baited with 16:1 ratio caught significantly more moths than those baited with a ratio approximating that of females. [ABSTRACT FROM AUTHOR]

Since its inception into Australian law less than two decades ago, change of position has become firmly established as the most important defence to a claim for restitution based on the concept of unjust enrichment. A lingering uncertainty, however, is the extent to which the defence can apply where restitution is claimed as a remedy for civil wrongs, such as conversion or breach of fiduciary duty. The author examines the nature and rationale of change of position and the policy behind restitutionary claims for conversion and breach of fiduciary duty, and argues that change of position should be applicable in these situations, provided the defendant has acted in good faith at all relevant times. [ABSTRACT FROM AUTHOR]

During the last decade Alloiococcus otitidis has been identified in specimens from patients with chronic otitis media with effusion. Whereas most of those studies employed molecular techniques, we used minor modifications of conventional microbiological methods to isolate and identify A. otitidis in samples obtained from 20/50 (40%) children referred for myringotomy. Alloiococcus otitidis was isolated from 10/22 (45%) Indigenous and 10/28 (36%) non-Indigenous children. This is the first report of isolation of A. otitidis from Australian children with chronic otitis media. All isolates were sensitive to penicillin, but 14/20 (70%) of the isolates were resistant or partially resistant to erythromycin as assessed by the E-test. [ABSTRACT FROM AUTHOR]

Abstract: What is causing the increasing densities of native shrubs, or so-called ‘woody weeds’, in some semi-arid pastoral lands and how might they be most effectively managed? This question has been on the rangeland policy agenda in Australia for more than one hundred years. This paper describes a fresh examination of this question using a systems approach. A key component of the approach involved ‘mapping the problem’. Using a systems-based approach, landholders developed four system diagrams broadly describing the ecology of woody weed re-occurrence, control options, property economics and management constraints with diagrams identifying how different factors related to, or influenced, each other. Agency personnel also constructed a system diagram describing institutional and regulatory constraints, and their interactions. Later, all these system diagrams formed the basis for an adaptive management model with capabilities for developing and quantitatively evaluating alternative management strategies relating to woody weeds. This model is called the Woody Weed Planner. The Woody Weed Planner contains mathematical relationships developed through field experimentation over the last 25–50 years covering the ecology of woody weeds, control options and control economics. These relationships enable the user to generate mathematical responses as a result of changing model parameters. A key component of the model is the ability to simulate the effects of alternative management responses given different rainfall scenarios. To enable this to occur, the Planner allows the user to replay historical rainfall patterns and ask the question “what impact will these have on woody weeds, stocking rates and economic performance on my property?” [Copyright &y& Elsevier]

Annual indoxacarb resistance in Helicoverpa armigera (Hübner) populations collected from various crops in Australia was monitored between 2013 and 2023. Resistance frequency determined by F2 screening using a predetermined discriminating dose of indoxacarb, was lowest in the 2013-2014 and 2015-2016 seasons at 0.0164 and 0.0246, respectively. Resistance then increased significantly to a ten-year high of 0.0869 in 2018-2019 but declined to 0.0557 in 2019-2020 during a severe drought, remaining relatively stable thereafter to 2023. Indoxacarb resistance was first detected in H. armigera collected from maize in the Gwydir valley, New South Wales, in 2013 (strain GY7-39). In 2017, a second indoxacarb resistant H. armigera strain (UN1U3-10) was isolated from a population collected in chickpeas in the Liverpool Plains, New South Wales. Indoxacarb resistance of this strain was characterized to evaluate its potential to compromise the ongoing effectiveness of insecticide resistance management strategies in Australian farming systems. Survival at the discriminating dose of indoxacarb in UN1U3-10 was 28.9, 52.6, 86.7, and 92.9% in the F2, F3, F4, and F5, respectively. Following introgression with a susceptible strain and reselection with the discriminating dose of indoxacarb, the resistance ratio of UN1U3-10 was approximately 800-fold. Resistance was autosomal, incompletely dominant and conferred by more than 1 locus. While indoxacarb resistance in UN1U3-10 did not confer to emamectin benzoate or spinetoram and there was no evidence of major cross-resistance to the Bt toxins Cry1A, Cry2A or Vip3A, there was 5-fold reduced sensitivity to chlorantraniliprole. Indoxacarb resistance was suppressed by approximately 10-fold by PBO with no synergism by TPP or DEM, suggesting the involvement of cytochrome P450 enzymes. A stability analysis indicated a fitness cost may be associated with the genes that confer resistance in the UN1U3-10 strain. The potential risk for diverse indoxacarb resistance in the Australian H. armigera population is discussed., (© The Author(s) 2023. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Susceptibility in Helicoverpa punctigera (Wallengren) to emamectin benzoate, chlorantraniliprole, and indoxacarb was established from feeding assays on insecticide-incorporated artificial diet in the laboratory. The variation in dose responses was examined in H. punctigera field populations collected in eastern Australia between September 2013 and January 2016 and compared with a laboratory strain. Chlorantraniliprole was the most toxic insecticide with an average LC50 of 3.7 µg of insecticide per liter of diet (n = 12 field strains). The average LC50 for emamectin benzoate was 5.6 µg of insecticide per liter of diet (n = 11 field strains), whereas indoxacarb had the lowest toxicity with an average LC50 of 172 µg of insecticide per liter of diet (n = 14 field strains). Variation in susceptibility between field strains was low at 1.9-, 2.4-, and 2-fold for chlorantraniliprole, emamectin benzoate, and indoxacarb, respectively. Narrow ranges of intra-specific tolerance, high slopes, and goodness-of-fit to a probit binomial model suggested feeding bioassays using insecticide-incorporated diet were a more effective laboratory method for measuring dose responses of these insecticides in H. punctigera than traditional topical bioassays. We propose discriminating concentrations of 0.032, 0.026, and 4 µg of insecticide/ml of diet for chlorantraniliprole, emamectin benzoate, and indoxacarb, respectively, to monitor insecticide resistance in H. punctigera. Although the potential for H. punctigera to develop insecticide resistance is considered low based on historical records, recent changes in population dynamics of this species in eastern Australia may have increased the risk of resistance development., (© The Author(s) 2018. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Objective: Recent reports have suggested a significant incidence of sensorineural hearing loss (SNHL) in children with Turner syndrome. This study reviewed a cohort of Australian children to clarify the incidence and pattern of conductive and sensorineural hearing loss., Methods: Retrospective cohort study of 23 individuals with Turner syndrome was identified - mean age 10 years 4 months. A retrospective review was undertaken and otologic status assigned., Results: Middle ear disease affected 91% of patients. Two children (9%) demonstrated sensorineural hearing loss attributable to Turner syndrome. Average age of onset was 15 years - one demonstrated a classic U-shaped mid-frequency loss, the other a bilateral down-sloping sensorineural loss., Conclusions: In this Turner syndrome cohort, 91% of subjects suffered middle ear disease, whilst the incidence of SNHL was 9%. It is recommended that individuals with Turner syndrome should be screened for onset and progression of hearing loss.

The Australian Plague Locust Commission (APLC) manages locust populations across 2 million square kilometers of eastern Australia using the aerial application of chemical and biological control agents to protect agricultural production. This occurs via a preventative control strategy involving ultralow-volume spray equipment to distribute small droplets of control agent over a target area. The economic costs of, and potential gains stemming from, locust control are well documented. The application of insecticides, however, to fragile arid and semiarid ecosystems is a task that brings with it both real and perceived environmental issues. The APLC is proactive in addressing these issues through a combination of targeted environmental operational research, an ISO-14001-aligned Environmental Management System (EMS), and links with environmental regulatory and research institutions. Increasing due diligence components within Australian environmental legislation dictate that mere legislative compliance is no longer sufficient for industries to ensure that they meet their environmental obligations. The development of external research links and the formulation of an EMS for locust control have enabled the APLC to identify environmental issues and trends, quantify objective environmental targets and strategies, and facilitate continuous improvement in its environmental performance, while maintaining stakeholder support. This article outlines the environmental issues faced by the APLC, the research programs in place to address these issues, and the procedures in place to incorporate research findings into the organization's operational structure.