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1.
Trends Ecol Evol ; 38(8): 727-735, 2023 08.
Article in English | MEDLINE | ID: mdl-37105850

ABSTRACT

A global technology arms race is underway to build evermore powerful and precise quantum computers. Quantum computers have the potential to tackle certain quantitative problems quicker than classical computers. The current focus of quantum computing is on pushing the boundaries of fundamental quantum information and commercial applications in industrial sectors, financial services, and other profit-led sectors, particularly where improvements in optimisation and sampling can improve increased economic return. We believe that ecologists could exploit the computational power of quantum computers because the statistical approaches commonly used in ecology already have proven pathways on quantum computers. Moreover, quantum computing could ultimately leapfrog our understanding of complex ecological systems, if the hardware, opportunity, and creativity of quantitative ecologists all align.


Subject(s)
Computing Methodologies , Quantum Theory , Computers , Ecology
2.
Mol Biol Evol ; 33(4): 995-1007, 2016 Apr.
Article in English | MEDLINE | ID: mdl-26739881

ABSTRACT

Mitochondria are critical for life, yet their underlying evolutionary biology is poorly understood. In particular, little is known about interaction between two levels of evolution: between individuals and within individuals (competition between cells, mitochondria or mitochondrial DNA molecules). Rapid evolution is suspected to occur frequently in mitochondrial DNA, whose maternal inheritance predisposes advantageous mutations to sweep rapidly though populations. Rapid evolution is also predicted in response to changed selection regimes after species invasion or removal of pathogens or competitors. Here, using empirical and simulated data from a model invasive bird species, we provide the first demonstration of rapid selection on the mitochondrial genome within individuals in the wild. Further, we show differences in mitochondrial DNA copy number associated with competing genetic variants, which may provide a mechanism for selection. We provide evidence for three rarely documented phenomena: selection associated with mitochondrial DNA abundance, selection on the mitochondrial control region, and contemporary selection during invasion.


Subject(s)
DNA, Mitochondrial/genetics , Evolution, Molecular , Genome, Mitochondrial/genetics , Selection, Genetic/genetics , Animals , Birds/genetics , Genetic Variation , Genotype , Introduced Species , Mitochondria/genetics , Mutation
3.
J Wildl Dis ; 50(4): 873-82, 2014 Oct.
Article in English | MEDLINE | ID: mdl-25105812

ABSTRACT

Abstract We report the clinical course and physiologic and anesthetic data for a case series of 76 free-ranging dromedary camels (Camelus dromedarius) chemically restrained, by remote injection from a helicopter, in the rangelands of Western Australia and South Australia, 2008-11, to attach satellite-tracking collars. Fifty-five camels were successfully anesthetized using medetomidine-ketamine (MK, n=27) and medetomidine-ketamine-butorphanol (MKB, n=28); the induction of anesthesia in 21 animals was considered unsuccessful. To produce reliable anesthesia for MK, medetomidine was administered at 0.22 mg/kg (± SD=0.05) and ketamine at 2.54 mg/kg (± 0.56), and for MKB, medetomidine was administered at 0.12 mg/kg (± 0.05), ketamine at 2.3 mg/kg (± 0.39), and butorphanol at 0.05 mg/kg (± 0.02). Median time-to-recumbency for MKB (8.5 min) was 2.5 min shorter than for MK (11 min) (P=0.13). For MK, the reversal atipamezole was administered at 0.24 mg/kg (± 0.10), and for MKB, atipamezole was administered at 0.23 mg/kg (± 0.13) and naltrexone at 0.17 mg/kg (± 0.16). Median time-to-recovery was 1 min shorter for MK (5 min) than MKB (6 min; P=0.02). Physiologic parameters during recumbency were not clinically different between the two regimes. Both regimes were suitable to safely anesthetize free-ranging camels; however, further investigation is required to find the safest, most consistent, and logistically practical combination.


Subject(s)
Anesthesia/veterinary , Butorphanol/pharmacology , Camelus , Ketamine/pharmacology , Medetomidine/pharmacology , Analgesics, Opioid/administration & dosage , Analgesics, Opioid/pharmacology , Anesthetics, Dissociative/administration & dosage , Anesthetics, Dissociative/pharmacology , Animals , Australia , Butorphanol/administration & dosage , Drug Therapy, Combination , Female , Hypnotics and Sedatives/administration & dosage , Hypnotics and Sedatives/pharmacology , Ketamine/administration & dosage , Male , Medetomidine/administration & dosage
4.
PLoS One ; 9(2): e97937, 2014.
Article in English | MEDLINE | ID: mdl-24918425

ABSTRACT

There is much interest in understanding how anthropogenic food resources subsidise carnivore populations. Carcasses of hunter-shot ungulates are a potentially substantial food source for mammalian carnivores. The sambar deer (Rusa unicolor) is a large (≥ 150 kg) exotic ungulate that can be hunted throughout the year in south-eastern Australia, and hunters are not required to remove or bury carcasses. We investigated how wild dogs/dingoes and their hybrids (Canis lupus familiaris/dingo), red foxes (Vulpes vulpes) and feral cats (Felis catus) utilised sambar deer carcasses during the peak hunting seasons (i.e. winter and spring). We placed carcasses at 1-km intervals along each of six transects that extended 4-km into forest from farm boundaries. Visits to carcasses were monitored using camera traps, and the rate of change in edible biomass estimated at ∼ 14-day intervals. Wild dogs and foxes fed on 70% and 60% of 30 carcasses, respectively, but feral cats seldom (10%) fed on carcasses. Spatial and temporal patterns of visits to carcasses were consistent with the hypothesis that foxes avoid wild dogs. Wild dog activity peaked at carcasses 2 and 3 km from farms, a likely legacy of wild dog control, whereas fox activity peaked at carcasses 0 and 4 km from farms. Wild dog activity peaked at dawn and dusk, whereas nearly all fox activity occurred after dusk and before dawn. Neither wild dogs nor foxes remained at carcasses for long periods and the amount of feeding activity by either species was a less important predictor of the loss of edible biomass than season. Reasons for the low impacts of wild dogs and foxes on sambar deer carcass biomass include the spatially and temporally unpredictable distribution of carcasses in the landscape, the rapid rate of edible biomass decomposition in warm periods, low wild dog densities and the availability of alternative food resources.


Subject(s)
Animals, Wild , Carnivory , Cats , Deer , Dogs , Foxes , Animals , Animals, Wild/physiology , Cats/physiology , Deer/physiology , Dogs/physiology , Female , Food , Foxes/physiology , Male , South Australia , Video Recording
5.
Accid Anal Prev ; 61: 311-6, 2013 Dec.
Article in English | MEDLINE | ID: mdl-23639888

ABSTRACT

BACKGROUND: Chronic health conditions associated with ageing can lead to changes in driving ability. The Canadian Driving Research Initiative for Vehicular Safety in the Elderly (Candrive II) is a 5-year prospective study funded by the Canadian Institutes of Health Research aiming to develop an in-office screening tool that will help clinicians identify potentially at-risk older drivers. Currently, no tools exist to directly predict the risk of motor vehicle collision (MVC) in this population. The American Medical Association (AMA), in collaboration with the National Highway Traffic Safety Association, has designed an opinion-based guide for assessing medical fitness to drive in older adults and recommends that physicians use the Assessment of Driving Related Skills (ADReS) as a test battery to measure vision, cognition and motor/somatosensory functions related to driving. The ADReS consists of the Snellen visual acuity test, visual fields by confrontation test, Trail Making Test part B, clock drawing test, Rapid Pace Walk, and manual tests of range of motion and motor strength. We used baseline data from the Candrive/Ozcandrive common cohort of older drivers to evaluate the validity of the ADReS subtests. We hypothesized that participants who crashed in the 2 years before the baseline assessment would have poorer scores on the ADReS subtests than participants who had not crashed. METHODS: In the Candrive/Ozcandrive study, 1230 participants aged 70 years or older were recruited from 7 Canadian cities, 1 Australian city and 1 New Zealand city, all of whom completed a comprehensive clinical assessment at study entry. The assessment included all tests selected as part of the ADReS. For this historical cohort study, data on all crashes (at-fault and non-at-fault) that occurred within 2 years preceding the baseline assessment were obtained from the respective licensing jurisdictions. Those who crashed were compared to those who had not crashed on their ADReS subtest scores using Pearson's chi-squared test and Student's t-test. RESULTS: Sixty-three of the 1230 participants (5.1%) were involved in an MVC within the 2 years preceding the baseline assessment. Contrary to our hypothesis, there were no statistically significant associations between abnormal performance on the tests constituting the ADReS and history of crash in the previous 2 years (p>0.01). DISCUSSION: We found that a history of crash in the previous 2 years was not associated with abnormalities on the subtests comprising the ADReS. This suggests the need for prospective analyses of risk factors over time to establish sensitive, valid predictors of crash that can be incorporated in clinical practice guidelines.


Subject(s)
Accidents, Traffic/statistics & numerical data , Automobile Driving/statistics & numerical data , Geriatric Assessment/statistics & numerical data , Practice Guidelines as Topic/standards , Aged , Aged, 80 and over , American Medical Association , Australia , Canada , Cohort Studies , Exercise Test , Female , Humans , Male , Neuropsychological Tests , New Zealand , Physical Examination , Retrospective Studies , United States , Vision Tests
6.
Respir Care ; 58(10): 1598-605, 2013 Oct.
Article in English | MEDLINE | ID: mdl-23550171

ABSTRACT

BACKGROUND: The purpose of this study was to compare the ability of 3 portable oxygen concentrators (POCs) to maintain S(pO2) ≥ 90% during exercise in patients with chronic lung disease. METHODS: Twenty-one subjects with chronic lung disease (18 with COPD, 3 with pulmonary fibrosis) and documented room air exertional S(pO2) ≤ 85% performed four 6-min walk tests: a control walk using the subject's current oxygen system and prescribed exertional flow rate, and 1 walk with each of the 3 POCs (Eclipse 3, EverGo, and iGo) at their maximum pulse-dose setting. RESULTS: S(pO2) was significantly higher pre-walk and post-walk with the Eclipse 3, compared to the other POCs (all P < .01). The subjects also walked farther and maintained a mean S(pO2) ≥ 90% with the Eclipse 3 (both P < .01), which delivers the largest oxygen bolus. The subjects indicated that they preferred the EverGo's physical characteristics, but that the Eclipse 3 responded best to their breathing. The iGo was rated less favorably than Eclipse 3 or EverGo. CONCLUSIONS: The Eclipse 3 was best at meeting the subjects' clinical needs. POC users should be appropriately tested during all activities of daily living, to ensure adequate oxygenation. The healthcare provider should provide information and help to direct the subject toward the most clinically appropriate oxygen system, while being mindful of the patient's preferences and lifestyle. (Clinicaltrials.gov NCT01653730).


Subject(s)
Oximetry/methods , Oxygen Consumption/physiology , Oxygen Inhalation Therapy/methods , Oxygen/metabolism , Pulmonary Disease, Chronic Obstructive/metabolism , Walking/physiology , Aged , Aged, 80 and over , Equipment Design , Exercise Test/instrumentation , Female , Follow-Up Studies , Forced Expiratory Volume , Humans , Male , Middle Aged , Pulmonary Disease, Chronic Obstructive/physiopathology , Pulmonary Disease, Chronic Obstructive/therapy , Retrospective Studies , Time Factors , Treatment Outcome
7.
Accid Anal Prev ; 61: 245-52, 2013 Dec.
Article in English | MEDLINE | ID: mdl-23541299

ABSTRACT

The Candrive II/Ozcandrive study, a multicentre prospective cohort study examining the predictive validity of tools for assessing fitness to drive, aims to develop an in-office screening tool that will help clinicians identify older drivers who may be unsafe to drive. This paper describes the study protocol. We are following a cohort of drivers aged ≥70 years for up to 4 years. Starting in 2009, 928 participants have been recruited in seven cities in four Canadian provinces, as well as 302 participants in two sites in Melbourne, Australia and Wellington, New Zealand. Participants underwent a comprehensive assessment at baseline and repeat the assessment yearly thereafter, as well as a brief follow-up assessment at 4 and 8 months each year. A recording device is installed in participants' vehicles to assess driving patterns, and driving records are obtained from licensing authorities to determine the outcomes: at-fault crashes per kilometre driven and violations. To date, the protocol has been generally well adhered to, with 1230 participants, and barriers and challenges are being addressed, as necessary. The Candrive II/Ozcandrive study is unique owing to its size, duration, partnerships with Canadian, Australian and New Zealand stakeholders, and international research collaboration.


Subject(s)
Accidents, Traffic/statistics & numerical data , Automobile Driving/statistics & numerical data , Health Status , Accidents, Traffic/prevention & control , Aged , Aged, 80 and over , Australia , Automobile Driver Examination , Canada , Cohort Studies , Decision Support Techniques , Female , Geriatric Assessment , Humans , Longitudinal Studies , Male , New Zealand , Prospective Studies
8.
Can Respir J ; 20(1): e5-9, 2013.
Article in English | MEDLINE | ID: mdl-23457679

ABSTRACT

BACKGROUND: Almost all patients with Duchenne muscular dystrophy (DMD) eventually develop respiratory failure. Once 24 h ventilation is required, either due to incomplete effectiveness of nocturnal noninvasive ventilation (NIV) or bulbar weakness, it is common practice to recommend invasive tracheostomy ventilation; however, noninvasive daytime mouthpiece ventilation (MPV) as an addition to nocturnal mask ventilation is also an alternative. METHODS: The authors' experience with 12 DMD patients who used 24 h NIV with mask NIV at night and MPV during daytime hours is reported. RESULTS: The mean (± SD) age and vital capacity (VC) at initiation of nocturnal (only) NIV subjects were 17.8±3.5 years and 0.90±0.40 L (21% predicted), respectively; and, at the time of MPV, 19.8±3.4 years and 0.57 L (13.2% predicted), respectively. In clinical practice, carbon dioxide (CO2) levels were measured using different methods: arterial blood gas analysis, transcutaneous partial pressure of CO2 and, predominantly, by end-tidal CO2. While the results suggested improved CO2 levels, these were not frequently confirmed by arterial blood gas measurement. The mean survival on 24 h NIV has been 5.7 years (range 0.17 to 12 years). Of the 12 patients, two deaths occurred after 3.75 and four years, respectively, on MPV; the remaining patients continue on 24 h NIV (range two months to 12 years; mean 5.3 years; median 3.5 years). CONCLUSIONS: Twenty-four hour NIV should be considered a safe alternative for patients with DMD because its use may obviate the need for tracheostomy in patients with chronic respiratory failure requiring more than nocturnal ventilation alone.


Subject(s)
Muscular Dystrophy, Duchenne/therapy , Noninvasive Ventilation , Adult , Humans , Noninvasive Ventilation/methods , Retrospective Studies , Time Factors , Tracheostomy , Young Adult
9.
Vet Microbiol ; 162(2-4): 921-929, 2013 Mar 23.
Article in English | MEDLINE | ID: mdl-23266110

ABSTRACT

Although wild pig populations are known to sometimes be infected by Salmonella, the situation in Australia has received little attention and few population-based, planned studies have been conducted. Understanding the distribution of Salmonella infections within wild pig populations allows the potential hazard posed to co-grazing livestock to be assessed. We sampled a remote and isolated wild pig population in northwestern Australia. Faecal and mesenteric lymph node samples were collected from 651 wild pigs at 93 locations and cultured for Salmonella. The population sampled was typical of wild pig populations in tropical areas of Australia, and sampling occurred approximately halfway through the population's breeding season (38% of the 229 adult females were pregnant and 35% were lactating). Overall, the prevalence of Salmonella infection based on culture of 546 freshly collected faecal samples was 36.3% (95% CI 32.1-40.7%), and based on culture of mesenteric lymph nodes was 11.9% (95% CI, 9.4-15.0%). A total of 39 serovars (139 isolates) were identified--29 in faecal samples and 24 in lymph node samples--however neither Salmonella enterica serovar Typhimurium nor Salmonella Cholerasuis were isolated. There was a significant (p<0.0001) disagreement between faecal and lymph node samples with respect to Salmonella isolation, with isolation more likely from faecal samples. Prevalence differed between age classes, with piglets being less likely to be faecal-positive but more likely to be lymph node positive than adults. The distribution of faecal-positive pigs was spatially structured, with spatial clusters being identified. Study results suggest that this population of wild pigs is highly endemic for Salmonella, and that Salmonella is transmitted from older to younger pigs, perhaps associated with landscape features such as water features. This might have implications for infection of co-grazing livestock within this environment.


Subject(s)
Salmonella Infections, Animal/epidemiology , Salmonella Infections, Animal/microbiology , Salmonella/isolation & purification , Swine Diseases/epidemiology , Swine Diseases/microbiology , Animals , Australia/epidemiology , Feces/microbiology , Female , Lactation , Male , Pregnancy , Prevalence , Salmonella/classification , Sus scrofa , Swine
10.
Can Geriatr J ; 15(4): 101-19, 2012 Dec.
Article in English | MEDLINE | ID: mdl-23259024

ABSTRACT

BACKGROUND: Many specialists encounter issues related to fitness to drive in their practices. We sought to determine the attitudes and practices of Canadian specialists regarding the assessment of medical fitness to drive in older persons. METHODS: We present data from a postal survey of 842 physicians certified in cardiology, endocrinology, geriatric medicine, neurology, neurosurgery, orthopaedic surgery, physical medicine and rehabilitation, or rheumatology regarding their attitudes and practices relating to the assessment of their patients' fitness to drive. RESULTS: Overall response rate was 55.1%. Except for rheumatologists (18%), most specialists reported that fitness to drive is an important issue in their practices (68%). Confidence in the ability to assess fitness to drive was low (33%), and the majority (73%) felt they would benefit from further education. There were significant differences (p < .05) in responses between physicians from different provinces, owing to reporting policies. More geriatricians than neurologists report drivers with mild Alzheimer disease to authorities regardless of reporting policy (mandatory 90.7% vs. 56.0%; non-mandatory 84.1% vs. 40.0%) (p < .05). CONCLUSIONS: Canadian specialists accept the responsibility of determining their patients' fitness to drive but are not fully confident in their ability to do so. However, they are receptive to education to improve their skills in this area.

11.
PLoS One ; 7(10): e46310, 2012.
Article in English | MEDLINE | ID: mdl-23071552

ABSTRACT

Infectious wildlife diseases have enormous global impacts, leading to human pandemics, global biodiversity declines and socio-economic hardship. Understanding how infection persists and is transmitted in wildlife is critical for managing diseases, but our understanding is limited. Our study aim was to better understand how infectious disease persists in wildlife populations by integrating genetics, ecology and epidemiology approaches. Specifically, we aimed to determine whether environmental or host factors were stronger drivers of Salmonella persistence or transmission within a remote and isolated wild pig (Sus scrofa) population. We determined the Salmonella infection status of wild pigs. Salmonella isolates were genotyped and a range of data was collected on putative risk factors for Salmonella transmission. We a priori identified several plausible biological hypotheses for Salmonella prevalence (cross sectional study design) versus transmission (molecular case series study design) and fit the data to these models. There were 543 wild pig Salmonella observations, sampled at 93 unique locations. Salmonella prevalence was 41% (95% confidence interval [CI]: 37-45%). The median Salmonella DICE coefficient (or Salmonella genetic similarity) was 52% (interquartile range [IQR]: 42-62%). Using the traditional cross sectional prevalence study design, the only supported model was based on the hypothesis that abundance of available ecological resources determines Salmonella prevalence in wild pigs. In the molecular study design, spatial proximity and herd membership as well as some individual risk factors (sex, condition score and relative density) determined transmission between pigs. Traditional cross sectional surveys and molecular epidemiological approaches are complementary and together can enhance understanding of disease ecology: abundance of ecological resources critical for wildlife influences Salmonella prevalence, whereas Salmonella transmission is driven by local spatial, social, density and individual factors, rather than resources. This enhanced understanding has implications for the control of diseases in wildlife populations. Attempts to manage wildlife disease using simplistic density approaches do not acknowledge the complexity of disease ecology.


Subject(s)
Animals, Wild , Ecology , Salmonella Infections/epidemiology , Swine Diseases/epidemiology , Animals , Australia , Cross-Sectional Studies , Data Collection , Salmonella Infections/genetics , Swine , Swine Diseases/genetics
12.
Am J Phys Med Rehabil ; 91(8): 666-70, 2012 Aug.
Article in English | MEDLINE | ID: mdl-22561386

ABSTRACT

OBJECTIVE: The aim of this study was to examine the relationship between cough peak flows (CPFs) before and after tracheostomy tube removal (decannulation) in patients with neuromuscular respiratory muscle weakness. DESIGN: For 26 patients with occluded tracheostomies (capped or Passy-Muir valve), spontaneous CPF (CPF(sp)), CPF after lung volume recruitment (CPF(LVR)), and CPF after lung volume recruitment and a manually assisted cough (CPF(LVR) + MAC) were measured before and after decannulation. RESULTS: Decannulation resulted in a significant increase (P < 0.001) in CPF of 35.6, 34.5, and 42.6 l/min for CPF(sp), CPF(LVR), and CPF(LVR) + MAC, respectively. In addition, CPF(LVR) or CPF(LVR) + MAC with a capped tracheostomy in place were greater than spontaneous CPF with the tracheostomy tube removed. CONCLUSIONS: Our study suggests that assisted coughing with a capped tracheostomy tube in place can result in higher flows than removing the tube and relying on spontaneous cough alone. Postdecannulation CPF measured at the mouth can be predicted to be at least 34.5 l/min greater than predecannulation values, which may thereby lower the threshold of the CPF indicated for safe decannulation.


Subject(s)
Cough/physiopathology , Device Removal , Muscle Weakness/physiopathology , Nervous System Diseases/physiopathology , Respiratory Muscles/physiopathology , Tracheostomy , Airway Management/methods , Humans , Muscle Weakness/therapy , Respiratory Mechanics/physiology
13.
J Wildl Dis ; 48(2): 435-43, 2012 Apr.
Article in English | MEDLINE | ID: mdl-22493118

ABSTRACT

The Judas technique is a method used for landscape control of feral donkeys (Equus asinus) in northern Australia. Central to the success of any Judas program is the safe, efficient, and humane attachment of the telemetry device. For feral donkeys, this involves the use of field immobilization. We examine the replacement of the current chemical capture agent, succinylcholine, with contemporary immobilization agents to achieve positive animal welfare outcomes. A combination of medetomidine and ketamine delivered by remote injection from a helicopter was used to capture 14 free-ranging feral donkeys for the fitting of telemetry collars in Western Australia in November 2010. Dose rates of 0.14 mg/kg medetomidine and 4.1 mg/kg ketamine were appropriate to immobilize animals in 9 min (± SD = 3). Mean recovery time (total time in recumbency) was 21 min (± 14). All animals recovered uneventfully after being administered atipamezole, a specific antagonist of medetomidine, intramuscularly at 0.35 mg/kg. Physiologic parameters were recorded during recumbency, with environment-related hyperthermia being the only abnormality recognized. No significant complications were encountered, and this drug combination represents an efficient approach to capturing wild donkeys. This new method allows a rapid, safe, cost-effective approach to the immobilization of feral donkeys for use as Judas animals. This drug combination will replace the relatively inhumane succinylcholine for the field immobilization of feral donkeys.


Subject(s)
Equidae/physiology , Hypnotics and Sedatives/antagonists & inhibitors , Hypnotics and Sedatives/pharmacology , Imidazoles/pharmacology , Immobilization/veterinary , Animals , Animals, Wild , Drug Combinations , Female , Heart Rate/drug effects , Immobilization/methods , Injections, Intramuscular/veterinary , Ketamine/antagonists & inhibitors , Ketamine/pharmacology , Male , Medetomidine/antagonists & inhibitors , Medetomidine/pharmacology
14.
Amyotroph Lateral Scler ; 13(1): 59-65, 2012 Jan.
Article in English | MEDLINE | ID: mdl-22214354

ABSTRACT

Our objective was to evaluate a single-session, hands-on education programme on mechanical ventilation for ALS patients and caregivers in terms of knowledge, change in affect and to determine whether ventilator decisions made after the education sessions predict those made later in life. Questionnaires were administered to 26 patients and 26 caregivers on four separate occasions. The questionnaires assessed knowledge of ventilatory support, feedback on the nature of the education programme, as well as self-reported emotional well-being. All patients were followed until their death or until initiation of invasive ventilation. Both groups demonstrated significant improvements in knowledge as a result of the education session which was retained after one month. There was no change in patient or caregiver reports' self-reported emotional well-being. The choices of ventilatory support expressed at one month (T4) accurately predicted the real-life clinical choices made by 76% of patients. Any difference resulted from choosing palliative care. Hands-on patient and caregiver education results in improved knowledge, assists in decision-making with respect to ventilatory support, and is not associated with a worsening of affect. It also provides for an accurate prediction of real-life choices and avoids undesired life support interventions and critical care admissions.


Subject(s)
Amyotrophic Lateral Sclerosis/therapy , Caregivers/psychology , Decision Making , Palliative Care/methods , Patient Education as Topic , Respiration, Artificial/psychology , Adult , Affect , Aged , Aged, 80 and over , Amyotrophic Lateral Sclerosis/physiopathology , Humans , Male , Middle Aged , Prospective Studies , Quality of Life , Respiration, Artificial/methods , Surveys and Questionnaires
15.
Mol Ecol ; 20(11): 2307-17, 2011 Jun.
Article in English | MEDLINE | ID: mdl-21507095

ABSTRACT

Mitochondrial DNA (mtDNA) can be a powerful genetic marker for tracing origins and history of invasive populations. Here, we use mtDNA to address questions relevant to the understanding of invasion pathways of common starlings (Sturnus vulgaris) into Western Australia (WA) and discuss the utility of this marker to provide information useful to invasive species management. Mitochondrial sequence data indicate two geographically restricted genetic groups within Australia. Evidence of dispersal from genetically distinct sources outside the sampled range of starlings in Australia suggests increased vigilance by management agencies may be required to prevent further incursions from widely separated localities. Overall, genetic diversity in Australia was lower than in samples from the native range. Within Australia, genetic diversity was lowest in the most recently colonized area in the west, indicating that demographic bottlenecks have occurred in this area. Evidence of restricted dispersal between localities on the edge of the range expansion (ERE) in WA and other Australian sampling localities suggests that localized control within the ERE may be effective in preventing further range expansion. Signatures of spatial and demographic expansion are present in mismatch analyses from sampling localities located at the ERE, but neutrality indices did not support this finding, suggesting that the former may be more sensitive to recent expansion. Additionally, mismatch analyses support the presence of admixture, which is likely to have occurred pre-introduction. We compare our findings with those from a microsatellite study of the same samples and discuss how the mtDNA analyses used here offer valuable and unique insights into the invasion history of introduced species.


Subject(s)
DNA, Mitochondrial/genetics , Introduced Species , Starlings/genetics , Animals , Base Sequence , Haplotypes/genetics , Molecular Sequence Data , Phylogeny , Population Dynamics , Western Australia
16.
Mol Ecol ; 18(8): 1560-73, 2009 Apr.
Article in English | MEDLINE | ID: mdl-19317845

ABSTRACT

Invasive species are known to cause environmental and economic damage, requiring management by control agencies worldwide. These species often become well established in new environments long before their detection, resulting in a lack of knowledge regarding their history and dynamics. When new invasions are discovered, information regarding the source and pathway of the invasion, and the degree of connectivity with other populations can greatly benefit management strategies. Here we use invasive common starling (Sturnus vulgaris) populations from Australia to demonstrate that genetic techniques can provide this information to aid management, even when applied to highly vagile species over continental scales. Analysis of data from 11 microsatellites in 662 individuals sampled at 17 localities across their introduced range in Australia revealed four populations. One population consisted of all sampling sites from the expansion front in Western Australia, where control efforts are focused. Despite evidence of genetic exchange over both contemporary and historical timescales, gene flow is low between this population and all three more easterly populations. This suggests that localized control of starlings on the expansion front may be an achievable goal and the long-standing practice of targeting select proximal eastern source populations may be ineffective on its own. However, even with low levels of gene flow, successful control of starlings on the expansion front will require vigilance, and genetic monitoring of this population can provide essential information to managers. The techniques used here are broadly applicable to invasive populations worldwide.


Subject(s)
Conservation of Natural Resources , Genetics, Population , Microsatellite Repeats , Starlings/genetics , Alleles , Animals , Cluster Analysis , Female , Gene Flow , Genetic Variation , Linear Models , Male , Population Dynamics , Sequence Analysis, DNA , Western Australia
17.
Oecologia ; 116(3): 293-305, 1998 Sep.
Article in English | MEDLINE | ID: mdl-28308060

ABSTRACT

Many ecological studies rely heavily on chemical analysis of plant and animal tissues. Often, there is limited time and money to perform all the required analyses and this can result in less than ideal sampling schemes and poor levels of replication. Near infrared reflectance spectroscopy (NIRS) can relieve these constraints because it can provide quick, non-destructive and quantitative analyses of an enormous range of organic constituents of plant and animal tissues. Near infrared spectra depend on the number and type of C[Formula: see text]H, N[Formula: see text]H and O[Formula: see text]H bonds in the material being analyzed. The spectral features are then combined with reliable compositional or functional analyses of the material in a predictive statistical model. This model is then used to predict the composition of new or unknown samples. NIRS can be used to analyze some specific elements (indirectly - e.g., N as protein) or well-defined compounds (e.g., starch) or more complex, poorly defined attributes of substances (e.g., fiber, animal food intake) have also been successfully modeled with NIRS technology. The accuracy and precision of the reference values for the calibration data set in part determines the quality of the predictions made by NIRS. However, NIRS analyses are often more precise than standard laboratory assays. The use of NIRS is not restricted to the simple determination of quantities of known compounds, but can also be used to discriminate between complex mixtures and to identify important compounds affecting attributes of interest. Near infrared reflectance spectroscopy is widely accepted for compositional and functional analyses in agriculture and manufacturing but its utility has not yet been recognized by the majority of ecologists conducting similar analyses. This paper aims to stimulate interest in NIRS and to illustrate some of the enormous variety of uses to which it can be put. We emphasize that care must be taken in the calibration stage to prevent propagation of poor analytical work through NIRS, but, used properly, NIRS offers ecologists enormous analytical power.

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