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Wild rabbits in Australia developed genetic resistance to the myxoma virus, which was introduced as a biological control agent. However, little is known about the rate at which this evolutionary change occurred. We collated data from challenge trials that estimated rabbit resistance to myxomatosis in Australia and expressed resistance on a continuous scale, enabling trends in its development to be assessed over 45 years up to 1995. Resistance initially increased rapidly, followed by a plateau lasting ten years, before a second rapid increase occurred associated with the introduction of European rabbit fleas as myxoma virus vectors. By contrast, in the United Kingdom, where rabbit flea vectors were already present when the myxoma virus initially spread, resistance developed more slowly. No estimates of rabbit resistance to myxomatosis have been made for almost 30 years, despite other highly lethal rabbit pathogens becoming established worldwide. Continued testing of wild-caught rabbits in Australia to determine current levels of resistance to myxomatosis is recommended to assess its current effectiveness for managing pest rabbits. Given the economic and environmental significance of invasive rabbits, it would be remiss to manage such biological resources and ecosystem services poorly.
The process of generating FMEA following document-centric approach is tedious and susceptible to human error. This paper presents preliminary methodology for robotic manufacturing process modelling in MBSE environment with a scope of automating multiple steps of the modelling process using ontology. This is followed by the reasoning towards automatic generation of process FMEA from the MBSE model. The proposed methodology allows to establish robust and self-synchronising links between process-relevant information, reduce the likelihood of human error, and scale down time expenses.
The collapse of South Asia's Gyps vulture populations is attributable to the veterinary use of the non-steroidal anti-inflammatory drug (NSAID) diclofenac. Vultures died after feeding on carcasses of recently-medicated animals. The governments of India, Nepal and Pakistan banned the veterinary use of diclofenac in 2006. We analysed results of 62 necropsies and 48 NSAID assays of liver and/or kidney for vultures of five species found dead in India between 2000 and 2012. Visceral gout and diclofenac were detected in vultures from nine states and three species: Gyps bengalensis, Gyps indicus and Gyps himalayensis. Visceral gout was found in every vulture carcass in which a measurable level of diclofenac was detected. Meloxicam, an NSAID of low toxicity to vultures, was found in two vultures and nimesulide in five vultures. Nimesulide at elevated tissue concentrations was associated with visceral gout in four of these cases, always without diclofenac, suggesting that nimesulide may have similar toxic effects to those of diclofenac. Residues of meloxicam on its own were never associated with visceral gout. The proportion of Gyps vultures found dead in the wild in India with measurable levels of diclofenac in their tissues showed a modest and non-significant decline since the ban on the veterinary use of diclofenac. The prevalence of visceral gout declined less, probably because some cases of visceral gout from 2008 onwards were associated with nimesulide rather than diclofenac. Veterinary use of nimesulide is a potential threat to the recovery of vulture populations.
Dysfunctions in the regulation of emotional responses are related to poor psychological well-being and increased impact of cardiovascular disease. It has been suggested that the relationship between negative affect and higher morbidity could be mediated by a dysregulation of the autonomic nervous system (ANS), for example, of heart rate variability (HRV). Neuroticism is a personality trait associated with a maladaptive emotion regulation and also with alterations in ANS function. However, it is unknown whether subjects with high neuroticism present with specific biases in emotion regulation associated with reduced HRV.
In total, 33 healthy subjects (n=13, highly neurotic) performed an emotion regulation task, during which they were instructed to either passively view negative pictures or attempt to down-regulate the affect elicited by the images. During the task an electrocardiogram was recorded and HRV was measured by calculation of the high frequency spectrum (HF-HRV).
A significant interaction between task condition and personality group was observed on HF-HRV measures (F1,31=6.569, p=0.016). This was driven by subjects with low neuroticism presenting higher HF-HRV during down-regulation compared to passive exposure to negative stimuli, while subjects with high neuroticism reported an opposite tendency.
Our results show reduced HF-HRV during cognitive reappraisal of negative stimuli in high neuroticism and indicate a specific link between loss of flexibility in the parasympathetic cardiovascular tone and emotion regulation, consistent with previous work. Such findings support the importance of exploring the combination of ANS adaptability and emotional dysregulation in neuroticism as different facets of a common psychosomatic vulnerability factor.
Restriction enzyme fingerprints were generated from purified plasmid DNA from 324 clinical isolates that belonged to 7 enterobacterial genera and 88 single plasmids in Escherichia coli K12 according to the following strategy.
Purified plasmid DNA was digested with PstI. The number of fragments detected in a 0·8 agarose gel was used to determine which 2 of 6 restriction enzymes including Pstl was most likely to provide a fingerprint comprising sufficient fragments to ensure specificity but sufficiently few to allow easy visual assessment and minimize coincidental matching. When PstI produced > 20 fragments, Eco RI and HindIII were used; when PstI generated < 6 fragments Bsp 1286 and AvaII were used and SmaI was employed when between 6 and 20 fragments were obtained from PstI digests. Using a minimum of 12 fragments from a combination of 2 enzymes as the criterion for characterizing a strain/plasmid, satisfactory 2-enzyme fingerprints were obtained from 87% of the strains and plasmids studied using PstI and no more than two additional enzymes per strain. Of the remaining 54 strains, 51 harboured only small plasmids (< 10 kb) and 3 produced satisfactory fingerprints when digested with a fourth enzyme.
Gyps vulture populations across the Indian subcontinent collapsed in the 1990s and continue to decline. Repeated population surveys showed that the rate of decline was so rapid that elevated mortality of adult birds must be a key demographic mechanism. Post mortem examination showed that the majority of dead vultures had visceral gout, due to kidney damage. The realisation that diclofenac, a non-steroidal anti-inflammatory drug potentially nephrotoxic to birds, had become a widely used veterinary medicine led to the identification of diclofenac poisoning as the cause of the decline. Surveys of diclofenac contamination of domestic ungulate carcasses, combined with vulture population modelling, show that the level of contamination is sufficient for it to be the sole cause of the decline. Testing on vultures of meloxicam, an alternative NSAID for livestock treatment, showed that it did not harm them at concentrations likely to be encountered by wild birds and would be a safe replacement for diclofenac. The manufacture of diclofenac for veterinary use has been banned, but its sale has not. Consequently, it may be some years before diclofenac is removed from the vultures' food supply. In the meantime, captive populations of three vulture species have been established to provide sources of birds for future reintroduction programmes.
Most mammals exhibit seasonal variation in the reproductive capacity of one or both sexes. While the female southern hairy-nosed wombat Lasiorhinus latifrons is a known seasonal breeder, the extent of seasonality in the male has not been documented. To examine this, gross body measurements including scrotal diameter and the dimensions of the accessory gland bulge were recorded and male reproductive tracts were examined between 1993 and 2000. Testes, epididymides and accessory glands from all males were dissected free of connective tissue and weighed. In addition, matched semen samples were collected over four time points in 2000 corresponding to the breeding season (September), immediately post-breeding season (November), during the non-breeding season (January), and immediately before the onset of the next breeding season (June) as determined from female reproductive status. Semen was collected by electro-ejaculation and analysed for volume, sperm number and motility characteristics. Ejaculate volume, total ejaculate sperm number, percentage motile sperm, and the sperm motility rating and index were all significantly elevated in September and significantly lower in November and January. This correlated with a significant increase in body weight, peri-cloacal gland width, and the weights of the prostate, Cowper's glands, urethral bulb and crus penis. The data confirm that male reproduction in the southern hairy-nosed wombat, like that of the female, is highly seasonal with a peak in reproductive capacity occurring in August–September and a reduction by November.
This study investigated burrow use and ranging behaviour in the southern hairy-nosed wombat Lasiorhinus latifrons in semi-arid South Australia. Sixteen adult wombats were fitted with radio transmitters and monitored monthly from July 2001 to February 2002. Wombats generally used between one and five warrens, preferred large warrens with a greater number of entrances and showed a preference for one or two warrens. Across the study period there was no apparent change in burrows used within warrens. Radio-tracking indicated that animals spent very little time above ground (26% of 1115 night-time fixes), centred their activity around their preferred warrens, and moved, on average, 99 m/h and 221 m/night. Mean home-range size, estimated using minimum convex polygons and the harmonic mean method from location data, obtained through triangulation, and daytime warren fixes, ranged from 1.3 to 4.8 ha. Home-range size was similar between males and females and home ranges overlapped substantially. The data highlight the importance of burrows to southern hairy-nosed wombats in shaping their home ranges. It seems likely that the use of burrows and a specialized diet are important energy saving strategies for this species in such unpredictable regions of South Australia.
Music education inherently relies on a process of providing and receiving critical feedback. Students who are very sensitive to criticism, however, may present a unique challenge for the music educator. This study investigated the ways in which sensitivity to criticism affects the educational experience of music students. Nineteen students were assessed for sensitivity to criticism, self-reported motivation, and perceived quality of performance early and late in the semester. High scores on the Sensitivity to Criticism Scale (Atlas, 1994) were associated with decreases in ratings of importance of the activity and mildly connected with decreases in enjoyment and confidence levels. Highly sensitive students were more hurt by their instructors’ criticisms, felt they improved less in response to criticism, and found it more difficult to communicate with the instructor following criticism. These results suggest that being sensitive to criticism can have an impact on music students’ motivation and performance – and that instructors should be particularly careful in considering the effects that critical feedback may have on highly sensitive students.
Antechinus agilis mate within a 2–3 week, highly synchronized period each year, with copulation consisting of short bouts of thrusting interrupted by longer bouts of rest during which time the male remains mounted. In the laboratory, mating can last as long as 8–12 h without any break in intromission, with captive paired animals generally copulating once per day (Woolley, 1966a,b). The mating programme used in this study examines the effects on copulatory behaviour of changing: (1) timing of access relative to ovulation; (2) order of mating; (3) the delay between the first and second males' mating access. The total mount time was divided into quarters and the changes in behavioural patterns assessed by examining changes in the frequency of five key activities; thrusting, pelvic side-to-side movements, walking, female resistance, and dismounts. No significant differences were observed in the time from initial pairing to first mount regardless of mating order or time of mating, nor was the total time mounted significantly affected by mating order. Significant reductions in the total time mounted were evident, however, for those males mating closer to the time of ovulation. The behavioural strategies associated with copulation in A. agilis significantly enhance arguments for equality between males and females in determining overall mating strategies.
The mouse-like marsupial Antechinus agilis is common to south-eastern Australia with breeding and life-history traits being highly synchronous. Mating activity is confined to a 10- to 15-day period in August, at the end of which all males die as a result of a stress-induced suppression of the immune system. Ovulation occurs at this time and females rely on stored sperm from specialized crypts in the lower isthmus of the oviduct for successful fertilization. Here we report a high incidence of mixed paternity litters, which can be attributed to sperm from multiple males being stored in the isthmic crypts. Data from this study also suggest a possible second male siring advantage in controlled ex situ sperm competition mating trials, irrespective of the delay between the two males being given mating access to the female or of the mating time relative to ovulation. In determining paternity through DNA profiling, population genetic data were obtained that showed significant differences in the genetic heterozygosity between unrelated adults, half siblings and full siblings. We suggest that the isthmic crypts, in addition to storing viable sperm, are capable of releasing a mix of sperm that increases the likelihood of mixed paternity litters. This allows all mating males the opportunity to sire young, increases female reproductive fitness and overall maintains high levels of population genetic heterozygosity in the face of total male mortality annually.
This study investigated the reproductive biology of a captive population of brush-tailed phascogales Phascogale tapoatafa. A ‘round robin’ mating system was established in which seven adult male animals were rotated through seven adult females. Changes in vaginal cytology and peripheral plasma progesterone and oestradiol levels were monitored to determine features of the female reproductive cycle. Regular measurement of scrotal diameter, collection of testicular biopsies and monitoring of plasma testosterone levels was used to assess male reproductive activity. Oestrous cycle length was estimated as 40 ± 5 days (n = 7) and gestation length as 27 ± 5 days (n = 7). Plasma progesterone levels showed no significant variation. This negative result is attributed to the small sample size (n = 4). Plasma oestradiol levels however, followed the predicted pattern, with an increase in peripheral concentration occurring prior to the breeding season. Oestradiol concentration peaked at 246.9 ± 169.2 pg ml−1 (mean ± SE) just before mating and declined to 24.3 ± 12.0 pg ml−1 after mating. Histological studies of testicular biopsies revealed that spermatogenesis does not cease until after the breeding season has begun, in contrast to Antechinus species, in which spermatogenesis ceases before breeding. Plasma testosterone levels increased at the onset of the breeding season, peaking at 6.3 ± 0.60 ng ml−1. Testosterone concentrations remained high until approximately 3 weeks after breeding, followed by a decline to pre-breeding levels. Litter size and sex ratio did not vary significantly between first- and second-year females. Females did not undergo a second oestrous cycle when pouch young were removed 15 and 17 days after parturition.
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