Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 1.099
Filter
1.
Skeletal Radiol ; 53(4): 779-789, 2024 Apr.
Article in English | MEDLINE | ID: mdl-37914895

ABSTRACT

OBJECTIVE: To evaluate whether 'fast,' unilateral, brachial plexus, 3D magnetic resonance neurography (MRN) acquisitions with deep learning reconstruction (DLR) provide similar image quality to longer, 'standard' scans without DLR. MATERIALS AND METHODS: An IRB-approved prospective cohort of 30 subjects (13F; mean age = 50.3 ± 17.8y) underwent clinical brachial plexus 3.0 T MRN with 3D oblique-coronal STIR-T2-weighted-FSE. 'Standard' and 'fast' scans (time reduction = 23-48%, mean = 33%) were reconstructed without and with DLR. Evaluation of signal-to-noise ratio (SNR) and edge sharpness was performed for 4 image stacks: 'standard non-DLR,' 'standard DLR,' 'fast non-DLR,' and 'fast DLR.' Three raters qualitatively evaluated 'standard non-DLR' and 'fast DLR' for i) bulk motion (4-point scale), ii) nerve conspicuity of proximal and distal suprascapular and axillary nerves (5-point scale), and iii) nerve signal intensity, size, architecture, and presence of a mass (binary). ANOVA or Wilcoxon signed rank test compared differences. Gwet's agreement coefficient (AC2) assessed inter-rater agreement. RESULTS: Quantitative SNR and edge sharpness were superior for DLR versus non-DLR (SNR by + 4.57 to + 6.56 [p < 0.001] for 'standard' and + 4.26 to + 4.37 [p < 0.001] for 'fast;' sharpness by + 0.23 to + 0.52/pixel for 'standard' [p < 0.018] and + 0.21 to + 0.25/pixel for 'fast' [p < 0.003]) and similar between 'standard non-DLR' and 'fast DLR' (SNR: p = 0.436-1, sharpness: p = 0.067-1). Qualitatively, 'standard non-DLR' and 'fast DLR' had similar motion artifact, as well as nerve conspicuity, signal intensity, size and morphology, with high inter-rater agreement (AC2: 'standard' = 0.70-0.98, 'fast DLR' = 0.69-0.97). CONCLUSION: DLR applied to faster, 3D MRN acquisitions provides similar image quality to standard scans. A faster, DL-enabled protocol may replace currently optimized non-DL protocols.


Subject(s)
Brachial Plexus , Deep Learning , Humans , Adult , Middle Aged , Aged , Magnetic Resonance Imaging/methods , Prospective Studies , Image Enhancement/methods , Brachial Plexus/anatomy & histology , Brachial Plexus/pathology
2.
Adv Mater ; 35(46): e2304455, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37734086

ABSTRACT

Electroadhesive devices with dielectric films can electrically program changes in stiffness and adhesion, but require hundreds of volts and are subject to failure by dielectric breakdown. Recent work on ionoelastomer heterojunctions has enabled reversible electroadhesion with low voltages, but these materials exhibit limited force capacities and high detachment forces. It is a grand challenge to engineer electroadhesives with large force capacities and programmable detachment at low voltages (<10 V). In this work, tough ionoelastomer/metal mesh composites with low surface energies are synthesized and surface roughness is controlled to realize sub-ten-volt clutches that are small, strong, and easily detachable. Models based on fracture and contact mechanics explain how clutch compliance and surface texture affect force capacity and contact area, which is validated over different geometries and voltages. These ionoelastomer clutches outperform the best existing electroadhesive clutches by fivefold in force capacity per unit area (102 N cm-2 ), with a 40-fold reduction in operating voltage (± 7.5 V). Finally, the ability of the ionoelastomer clutches to resist bending moments in a finger wearable and as a reversible adhesive in an adjustable phone mount is demonstrated.

3.
Eur J Radiol ; 156: 110492, 2022 Nov.
Article in English | MEDLINE | ID: mdl-36108480

ABSTRACT

OBJECTIVES: Septic shock is a potentially fatal condition. This study aims to assess whether iodine uptake and iodine density of abdominal organs on dual-layer spectral detector computed tomography (SDCT) could serve as a new imaging biomarker for patients in septic shock. METHODS: Here, 95 patients who received contrast-enhanced abdominal CT examinations were included and separated into two groups: group A - septic shock; group B - no shock condition. Preselected abdominal (right and left adrenal gland, right and left kidney, infrarenal inferior vena cava (IVC), pancreas, spleen, and liver) localizations were independently evaluated by two radiologists, who measured iodine concentrations (mg/ml) and Hounsfield units (HU). RESULTS: In all, 1520 measurements of iodine concentrations in mg/ml and HU were performed, with 27 patients in group A and 68 in group B. Iodine concentrations in mg/ml and HU correlated significantly in all organs measured. The corresponding correlation coefficient (r) ranged from 0.809 (pancreas) to 0.963 (right kidney). Inter-rater reliability (IRR) was very good for mg/ml (κ = 0.8; p < 0.01) and good for HU (κ = 0.773; p < 0.01) measurements. The mean iodine concentration and HU of the adrenal glands in septic and nonseptic patients was 4.88 ± 1.16 mg/ml/153 ± 36 HU and 2.67 ± 1.07 mg/ml/112 ± 41 HU, respectively. Iodine concentrations in the adrenal glands were significantly higher in group A than in group B patients (p < 0.01). The other organs remained unaffected and no significant difference was observed between patients in group A and B. Patients in group A presented significantly more often with an iodine uptake of >3.5 mg/ml of one adrenal gland (sensitivity = 0.926, specificity = 0.849, AUC = 0.951) or/and a combined concentration of >7 mg/ml of both adrenal glands (sensitivity = 0.889, specificity = 0.836, AUC = 0.928). CONCLUSION: SDCT-derived iodine concentration of the adrenal glands could serve as a novel imaging biomarker for patients in acute septic shock. Our data suggest that an iodine uptake of >3.5 mg/ml of at least one adrenal gland or a combined iodine uptake of >7 mg/ml in both adrenal glands identifies patients in this condition.

4.
Front Nutr ; 9: 917880, 2022.
Article in English | MEDLINE | ID: mdl-35942169

ABSTRACT

Objectives: In utero glycemia is an important determinant of fetal growth. Women with gestational diabetes are more likely to deliver large-for-gestational age babies that are at increased risk for obesity. The maternal nutritional state modulates the development of offspring biological systems during the critical periods of gestation and lactation. Carbohydrate typically contributes most of the dietary energy, however, there are very few mechanistic studies investigating the effects of maternal dietary carbohydrate quality on fetal and offspring outcomes. Therefore, we sought to investigate the direct effects of maternal carbohydrate quality on sex-specific offspring metabolic programming. Methods: Female C57BL/6 mice were fed one of five isocaloric diets: four high-sugar diets based on glucose, sucrose, isomaltulose or fructose (all containing 60% energy as carbohydrate), or a standard, minimally processed, chow diet, and were mated with chow-fed males. Half of the dams were sacrificed for fetus dissection and placental collection, with the remaining giving live birth. All dams were metabolically profiled before and during pregnancy, and pups were similarly profiled at 12 weeks of age. Results: Overall, glucose-fed dams were heavier and fatter than chow or isomaltulose-fed dams. Female fetuses from glucose and isomaltulose-fed mothers weighed less and had smaller livers, than those from chow-fed mothers, with isomaltulose-fed female fetuses also having decreased placental mass. In contrast, male fetuses responded differently to the maternal diets, with heart mass being significantly increased when their mothers were fed fructose-containing diets, that is, sucrose, isomaltulose and fructose. High-sugar fed female offspring weighed the same, but were significantly fatter, than chow-fed offspring at 12 weeks of age, while glucose and isomaltulose-fed male pups displayed a similar phenotype to their mothers'. Conclusion: While both glucose and isomaltulose diets constrained fetal growth in females, only placentas from isomaltulose-fed dams were significantly smaller than those from chow-fed mothers, suggesting the mechanisms through which fetal growth is reduced may be different. Female fetuses of isomaltulose-fed mothers were also lighter than sucrose-fed fetuses suggesting the glycemic index, or rate of glucose digestion and absorption, may be an important factor in determining nutrient availability to the growing fetus.

5.
J Arthroplasty ; 37(8): 1470-1473, 2022 08.
Article in English | MEDLINE | ID: mdl-35304300

ABSTRACT

The orthopedic environment exposes surgeons and staff to infection, surgical smoke, and high levels of noise. It is helpful to understand how exposure increases the risk for adverse health consequences. Protective equipment, safety protocols, and instrument modification can reduce exposure to hazards. When modifications to practice are made, they must be evaluated to ensure they do not introduce new hazards or impede the use of instruments. Despite evidence of risk, protective measures are seldom employed in orthopedic practice. Wider implementation of protection for clinicians may not occur unless the same hazards are shown to impact patient outcomes.


Subject(s)
Hearing Loss, Noise-Induced , Noise, Occupational , Occupational Exposure , Orthopedic Procedures , Orthopedics , Humans , Noise, Occupational/adverse effects , Noise, Occupational/prevention & control , Occupational Exposure/adverse effects , Orthopedic Procedures/adverse effects , Smoke/adverse effects
6.
Phys Rev Lett ; 128(9): 090401, 2022 Mar 04.
Article in English | MEDLINE | ID: mdl-35302825

ABSTRACT

In the expanding universe, relativistic scalar fields are thought to be attenuated by "Hubble friction," which results from the dilation of the underlying spacetime metric. By contrast, in a contracting universe this pseudofriction would lead to amplification. Here, we experimentally measure, with fivefold better accuracy, both Hubble attenuation and amplification in expanding and contracting toroidally shaped Bose-Einstein condensates, in which phonons are analogous to cosmological scalar fields. We find that the observed attenuation or amplification depends on the temporal phase of the phonon field, which is only possible for nonadiabatic dynamics. The measured strength of the Hubble friction disagrees with recent theory [Gomez Llorente et al., Phys. Rev. A 100, 043613 (2019)PLRAAN2469-992610.1103/PhysRevA.100.043613 and Eckel et al., SciPost Phys. 10, 64 (2021)SPCHCW2542-465310.21468/SciPostPhys.10.3.064].

7.
Prev Vet Med ; 198: 105535, 2022 Jan.
Article in English | MEDLINE | ID: mdl-34785439

ABSTRACT

Traditionally considered an agent affecting domestic dogs, canine distemper virus (CDV) is now well known for an ability to infect a broad range of hosts. In Ontario, domestic dogs are routinely vaccinated and clinical disease attributed to CDV infection in this population is infrequent. CDV has been regularly documented in Ontario wildlife spanning at least 4 decades however, the molecular identity of circulating CDV strains is currently unknown. Our objective was to investigate the molecular identities of and genetic relationships between CDV detected in wild and domestic animals from Canada, across multiple host species and over time. Samples were opportunistically collected from submissions to the Ontario-Nunavut node of the Canadian Wildlife Health Cooperative and the Animal Health Laboratory in Guelph, Ontario. RT-PCR was used to confirm CDV diagnosis, and the hemagglutinin gene was sequenced. Phylogenetic relationships were inferred, and the geographic distribution of clades was visualized using a geographic information system. Phenetic relationships between sequences were investigated with a median joining network analysis and through mixed multivariable linear regression. CDV sequences from ten wild and domestic species were characterized into seven lineages, that overlapped geographically and temporally. The predominant lineage circulating in Ontario wildlife, denoted Canada-1, has not been previously described to the authors knowledge. Our analysis indicates that the Canada-1 lineage is most genetically similar to America-1 sequences, however according to current methodology represents a distinct lineage. Multiple co-circulating CDV lineages were also identified, and raccoons appear to play an important role in the maintenance and transmission of these heterogeneous lineages in Ontario. This study also confirmed the presence of CDV from a lineage not found to be circulating in Ontario wildlife, in a domestic dog imported into Ontario from South America. Therefore, travel and the trade of animals may be an important avenue for the introduction of novel CDV lineages. It remains unclear whether and to what extent the genetic heterogeneity identified poses a risk to the efficacy of current vaccines. Increasing viral activity and continued antigenic drift resulting in partial protection or vaccine failure remains a concern.


Subject(s)
Distemper Virus, Canine , Distemper , Dog Diseases , Animals , Animals, Domestic , Antigenic Drift and Shift , Distemper/epidemiology , Distemper Virus, Canine/genetics , Dogs , Ontario/epidemiology , Phylogeny
8.
Rev Sci Instrum ; 92(5): 055107, 2021 May 01.
Article in English | MEDLINE | ID: mdl-34243343

ABSTRACT

Most atomic physics experiments are controlled by a digital pattern generator used to synchronize all equipment by providing triggers and clocks. Recently, the availability of well-documented open-source development tools has lifted the barriers to using programmable systems on chip (PSoCs), making them a convenient and versatile tool for synthesizing digital patterns. Here, we take advantage of these advancements in the design of a versatile clock and pattern generator using a PSoC. We present our design with the intent of highlighting the new possibilities that PSoCs have to offer in terms of flexibility. We provide a robust hardware carrier and basic firmware implementation that can be expanded and modified for other uses.

9.
Clin Toxicol (Phila) ; 59(3): 224-230, 2021 Mar.
Article in English | MEDLINE | ID: mdl-32633579

ABSTRACT

INTRODUCTION: There have been increasing reports documenting barbiturate-related deaths, despite routine prescribing for only relatively rare indications. The aims of the current study were to examine trends in barbiturate-related deaths in Australia from 2000 to 2019 and determine the case characteristics and circumstances of barbiturate-related deaths. METHODS: All barbiturate-related deaths identified in the Australian National Coronial Information System were examined. Information was collected on cause, manner, demographics, location, psychosocial factors, circumstances of deaths and toxicology. We examined these based on the age categories 18-44 years, 45-64 years and ≥65 years. RESULTS: We identified 511 cases. Mean age was 57.9 years (SD 20.2, range 18-100) and 56% were male. Intentional poisoning was the most common cause of death (87.5%) and was slightly higher in the oldest age group (92.1%) and lowest in the youngest age group (81.1%). Pentobarbitone was the most common barbiturate (75.7%) and pentobarbitone-related deaths increased from 0% in 2000 to 93.6% in 2017. There were notable differences between age categories, with the youngest age group recording more severe psychiatric histories. In contrast, the oldest age group were more likely to have severe physical health problems, such as cancer, chronic non-cancer pain, neurological conditions and significant cardiopulmonary morbidity. Euthanasia resources were commonly documented (33.9%), most frequently in the oldest age group (52.3%). CONCLUSION: Barbiturate-related deaths in Australia are increasing, particularly pentobarbitone-related deaths. Most deaths were intentional and involved adults across the lifespan. Younger people were more likely to have significant mental health problems, whilst the oldest age group were more likely to have severe physical health conditions.


Subject(s)
Barbiturates/toxicity , Drug Overdose/mortality , Hypnotics and Sedatives/toxicity , Adolescent , Adult , Age Factors , Aged , Aged, 80 and over , Australia/epidemiology , Female , Humans , Male , Middle Aged , Pentobarbital/toxicity , Psychology , Retrospective Studies , Risk Factors , Young Adult
10.
Rev Sci Instrum ; 91(10): 103202, 2020 Oct 01.
Article in English | MEDLINE | ID: mdl-33138581

ABSTRACT

We demonstrate a compact magneto-optical trap (MOT) of alkaline-earth atoms using a nanofabricated diffraction grating chip. A single input laser beam, resonant with the broad 1S0 → 1P1 transition of strontium, forms the MOT in combination with three diffracted beams from the grating chip and a magnetic field produced by permanent magnets. A differential pumping tube limits the effect of the heated, effusive source on the background pressure in the trapping region. The system has a total volume of around 2.4 l. With our setup, we have trapped up to 5 × 106 88Sr atoms at a temperature of ∼6 mK, and with a trap lifetime of ∼1 s. Our results will aid the effort to miniaturize quantum technologies based on alkaline-earth atoms.

11.
Food Chem ; 315: 126221, 2020 Jun 15.
Article in English | MEDLINE | ID: mdl-32000077

ABSTRACT

Xylo- and arabinoxylo-oligosaccharides (XOS and AXOS) are of interest for their prebiotic activity. The production of these oligomers might be accompanied with monosaccharides. The measurement of both oligosaccharides and monosaccharides usually requires two methods. The current work presents an HPAEC-PAD method based on gradient elution of aqueous solvents sodium hydroxide and sodium acetate, in contrast to conventional isocratic elution, for the simultaneous separation of 16 standards of monosaccharides, xylo-oligosaccharides, arabinoxylo-oligosaccharides and uronic acids using CarboPac PA 200 column. The presented method showed a stable baseline and high-resolution separation of the standards. The method showed acceptable accuracy and precision. Limits of Detection and Quantitation (LOD and LOQ) were estimated for all the standards. The method was applied to measure the activity of a commercial endoxylanase on wheat bran; a steady release of xylose monosaccharide was observed. Enzyme action on oligosaccharide standards showed a preference for the larger oligosaccharides.


Subject(s)
Monosaccharides/analysis , Oligosaccharides/analysis , Prebiotics/analysis , Triticum/chemistry , Arabinose/analysis , Arabinose/metabolism , Chromatography, Ion Exchange , Dietary Fiber , Edible Grain/chemistry , Endo-1,4-beta Xylanases/metabolism , Limit of Detection , Monosaccharides/metabolism , Oligosaccharides/metabolism , Reproducibility of Results , Uronic Acids/chemistry , Xylose/analysis , Xylose/metabolism
12.
Clin Oncol (R Coll Radiol) ; 32(4): 221-227, 2020 04.
Article in English | MEDLINE | ID: mdl-31740191

ABSTRACT

AIMS: Breast cosmesis is an important outcome for women after breast conservation. It has been shown to be correlated with better patient satisfaction, sexuality and self-esteem. This study reports the subjective and objective breast cosmesis outcomes for women treated at Auckland Hospital Radiation Oncology Department using hypofractionated radiation therapy. MATERIALS AND METHODS: Breast cosmesis was evaluated using a subjective questionnaire and standardised photographs before radiation, at 6 weeks, 1 year, 3 years and 5 years after radiation. Objective evaluation of the photographs and completion of questionnaires were undertaken by clinicians at the same time points. The questionnaire evaluated global cosmesis on a four-point scale - excellent (E), good (G), fair (F) and poor (P). Patient, tumour and treatment factors were evaluated to assess the impact on cosmesis. RESULTS: Three hundred and fifty-eight patients completed the baseline assessments and two hundred and two patients completed the 5-year assessments. Sixty-eight per cent of patients at baseline and 70% at 5 years scored their cosmesis as E/G compared with 52% and 51%, respectively, by clinician assessment. Age >50 years, separation ≤25 cm, non-diabetic, T1 tumours, node negative, quadrant of the scar, no boost and no adjuvant endocrine therapy were correlated with E/G cosmesis. On multivariate analysis at baseline, the individual breast factors that were significantly associated with a score of E/G cosmesis were breast shape (P = 0.028) and scar appearance (P = 0.001). At 5 years, breast shape (P = 0.003), nipple shape (P = 0.019) and scar appearance (P = 0.001) were found to be significant. CONCLUSION: This study shows that most women reported no significant change in their breast cosmesis after hypofractionated radiation treatment over 5 years and that a number of patient, tumour and treatment factors may impact on breast cosmesis.


Subject(s)
Breast Neoplasms/radiotherapy , Breast Neoplasms/surgery , Esthetics/psychology , Breast Neoplasms/pathology , Dose Fractionation, Radiation , Female , Humans , Male , Mastectomy, Segmental/methods , Middle Aged , New Zealand , Prospective Studies , Treatment Outcome
13.
Emerg Infect Dis ; 25(2): 265-272, 2019 02.
Article in English | MEDLINE | ID: mdl-30666935

ABSTRACT

Alveolar echinococcosis, the disease caused by infection with the intermediate stage of the Echinococcus multilocularis tapeworm, is typically fatal in humans and dogs when left untreated. Since 2012, alveolar echinococcosis has been diagnosed in 5 dogs, 3 lemurs, and 1 chipmunk in southern Ontario, Canada, a region previously considered free of these tapeworms. Because of human and animal health concerns, we estimated prevalence of infection in wild canids across southern Ontario. During 2015-2017, we collected fecal samples from 460 wild canids (416 coyotes, 44 foxes) during postmortem examination and analyzed them by using a semiautomated magnetic capture probe DNA extraction and real-time PCR method for E. multilocularis DNA. Surprisingly, 23% (95% CI 20%-27%) of samples tested positive. By using a spatial scan test, we identified an infection cluster (relative risk 2.26; p = 0.002) in the western-central region of the province. The cluster encompasses areas of dense human population, suggesting zoonotic transmission.


Subject(s)
Animal Diseases/epidemiology , Animal Diseases/microbiology , Echinococcosis/epidemiology , Echinococcosis/microbiology , Echinococcus multilocularis , Animals , Echinococcus multilocularis/genetics , Geography, Medical , Ontario/epidemiology , Prevalence , Public Health Surveillance
14.
Nat Commun ; 9(1): 4360, 2018 10 19.
Article in English | MEDLINE | ID: mdl-30341301

ABSTRACT

Machine learning based on artificial neural networks has emerged as an efficient means to develop empirical models of complex systems. Cold atomic ensembles have become commonplace in laboratories around the world, however, many-body interactions give rise to complex dynamics that preclude precise analytic optimisation of the cooling and trapping process. Here, we implement a deep artificial neural network to optimise the magneto-optic cooling and trapping of neutral atomic ensembles. The solution identified by machine learning is radically different to the smoothly varying adiabatic solutions currently used. Despite this, the solutions outperform best known solutions producing higher optical densities.


Subject(s)
Deep Learning , Magnetics , Optics and Photonics , Algorithms , Neural Networks, Computer
15.
J Wildl Dis ; 54(3): 622-625, 2018 07.
Article in English | MEDLINE | ID: mdl-29517402

ABSTRACT

Rabies and canine distemper virus infections in wildlife share similar presenting signs. Canine distemper virus was detected using real-time PCR of conjunctival swabs in rabies positive raccoons (22/32) and skunks (7/34) during a concurrent rabies and canine distemper outbreak in Ontario, Canada in 2015-16. Coinfections with both viruses should be considered, particularly in distemper endemic areas that are at risk of rabies incursion.


Subject(s)
Distemper Virus, Canine/isolation & purification , Distemper/complications , Mephitidae/virology , Rabies virus/isolation & purification , Rabies/veterinary , Raccoons/virology , Animals , Animals, Wild , Coinfection/epidemiology , Conjunctiva/virology , Disease Outbreaks , Distemper/epidemiology , Distemper/virology , Ontario/epidemiology , Rabies/complications , Rabies/epidemiology , Rabies/virology
16.
J Vet Diagn Invest ; 30(2): 319-323, 2018 Mar.
Article in English | MEDLINE | ID: mdl-29284384

ABSTRACT

Canine distemper virus (CDV) is a widespread morbillivirus that causes subclinical to fatal infections in domestic and wild carnivores. Raccoons ( Procyon lotor) are CDV reservoirs and suffer from associated disease. Aspects of pathogenesis may lead to difficulty in the interpretation of commonly used testing modalities, such as reverse-transcription real-time (RT-rt)PCR and immunohistochemistry (IHC). The reliance upon such tests is greater for wildlife, which are often submitted as carcasses with no clinical history. We compared CDV RT-rtPCR results to immunohistochemistry (the gold standard) in tissues from 74 raccoons. These tests had high kappa agreement (lymph node: 0.9335; lung: 0.8671) and a negative correlation between IHC score and threshold cycle (Ct) value for lymph node and lung (Spearman rank correlation coefficient [ rs] = -0.8555 and -0.8179, respectively; p < 0.00001). An RT-rtPCR Ct value of 30 in lung and lymph node with sensitivity and specificity of 92.3 and 92.6% and 86.8 and 96.4%, respectively, was suitable for determining CDV involvement. Conjunctival swabs provide an alternative for distemper diagnosis, as there was a strong correlation between Ct values of conjunctival swabs and tissues ( rs = -0.8498, p < 0.00001, n = 46). This information will aid in more efficient and accurate diagnoses in individuals, small-scale outbreaks, and epidemiologic investigations in wildlife.


Subject(s)
Disease Outbreaks/veterinary , Distemper Virus, Canine/isolation & purification , Distemper/epidemiology , Raccoons , Animals , Animals, Wild , Distemper/virology , Distemper Virus, Canine/genetics , Female , Immunohistochemistry/veterinary , Male , Ontario/epidemiology , Real-Time Polymerase Chain Reaction/veterinary , Sensitivity and Specificity
17.
Arch Environ Contam Toxicol ; 74(2): 305-317, 2018 Feb.
Article in English | MEDLINE | ID: mdl-29164278

ABSTRACT

We examined the degree of exposure of lead (Pb), mercury (Hg), and several organohalogen contaminants and its potential impact on survival of bald eagles in Ontario from 1991 to 2008. Overall, results for 43 dead or dying bald eagles collected in the province indicate that 23% (10/43) of birds died of Pb poisoning and 9% (4/43) died of suspected Hg poisoning. Pb poisoning was diagnosed based on exceedances of toxicity thresholds in liver and kidney and supported by clinical observations, necropsy results, and histology findings when available. Evidence for Hg poisoning in eagles was limited; however, Hg concentrations exceeded the toxicity threshold in kidney. Pb concentrations ranged widely in liver and kidney. Total Hg concentrations were relatively higher in kidney compared with liver and were significantly correlated with selenium (Se) concentrations in both tissues. Concentrations of p,p'-DDE and sum PCBs in livers of 12 bald eagles collected from 2001 to 2004 were likely below concentrations associated with adverse effects. Hepatic concentrations of total polybrominated diphenyl ethers were generally higher in birds collected from southern Ontario compared with northern Ontario. Potential impacts of exposure to these flame retardants and others are not known. Elevated metal exposure appears to influence survivorship and may affect the recovery of bald eagles in the province, particularly in southern Ontario and along the Great Lakes where a disproportionate number of poisoned eagles were collected. Increased efforts are needed to identify sources of exposure and develop measures to reduce metal exposure in this top predator.


Subject(s)
Eagles/physiology , Environmental Exposure/analysis , Environmental Pollutants/analysis , Metals/analysis , Animals , Dichlorodiphenyl Dichloroethylene/analysis , Environmental Monitoring/methods , Flame Retardants/analysis , Flame Retardants/pharmacokinetics , Hydrocarbons, Chlorinated/analysis , Hydrocarbons, Chlorinated/pharmacokinetics , Kidney/chemistry , Liver/chemistry , Male , Mercury/analysis , Metals/pharmacokinetics , Ontario , Polychlorinated Biphenyls/analysis , Polychlorinated Biphenyls/pharmacokinetics , Selenium/analysis , Tissue Distribution
18.
J Wildl Dis ; 54(2): 261-271, 2018 04.
Article in English | MEDLINE | ID: mdl-29154686

ABSTRACT

The causes of mortality of free-ranging raptors range from anthropogenic (e.g., trauma) to dynamic environmental conditions that may affect habitat suitability and prey availability. The province of Ontario, Canada, is vulnerable to anthropogenic and environmental changes because of its northern latitudes and expanding human populations, both of which may impact wildlife. We retrospectively evaluated diagnostic data from raptors submitted to the Ontario/Nunavut node of the Canadian Wildlife Health Cooperative (CWHC) from 1991 to 2014 ( n=1,448). Submissions encompassed 29 species, most commonly the Red-tailed Hawk ( Buteo jamaicensis; n=308) and Great Horned Owl ( Bubo virginianus; n=237). Trauma ( n=716) accounted for the majority of deaths among all species, followed by emaciation ( n=241). Traumatic deaths were most commonly attributed to collisions with stationary objects, and the odds of a diagnosis of trauma were significantly higher in adult versus immature raptors. The odds of being diagnosed with emaciation were significantly higher in males than in females but not in any age class or season. Mortality was less commonly attributed to infectious diseases ( n=214), for which West Nile virus (WNV) was the most common etiology, making up 53.1% of infectious diagnoses after its 2001 arrival in Ontario. The odds of a raptor being diagnosed with an infectious disease were significantly greater in summer and fall versus spring. Immature Red-tailed Hawks had significantly greater odds of being diagnosed with WNV compared to adults. These results reveal that human- and potentially environmentally-associated deaths (e.g., trauma and emaciation, respectively) are commonly diagnosed among Ontario raptors submitted to the CWHC. Infectious diseases are less commonly diagnosed, but WNV may have underlying, ongoing impacts on the health of some raptor species.


Subject(s)
Bird Diseases/virology , Raptors , West Nile Fever/veterinary , West Nile virus/isolation & purification , Animals , Bird Diseases/epidemiology , Bird Diseases/mortality , Female , Male , Ontario/epidemiology , Retrospective Studies , Seasons , West Nile Fever/epidemiology , West Nile Fever/mortality , West Nile Fever/virology , Wounds and Injuries/epidemiology , Wounds and Injuries/mortality , Wounds and Injuries/veterinary
19.
Phys Rev X ; 82018.
Article in English | MEDLINE | ID: mdl-31275731

ABSTRACT

We study the dynamics of a supersonically expanding ring-shaped Bose-Einstein condensate both experimentally and theoretically. The expansion redshifts long-wavelength excitations, as in an expanding universe. After expansion, energy in the radial mode leads to the production of bulk topological excitations - solitons and vortices - driving the production of a large number of azimuthal phonons and, at late times, causing stochastic persistent currents. These complex nonlinear dynamics, fueled by the energy stored coherently in one mode, are reminiscent of a type of "preheating" that may have taken place at the end of inflation.

20.
Vet Parasitol Reg Stud Reports ; 13: 234-237, 2018 08.
Article in English | MEDLINE | ID: mdl-31014882

ABSTRACT

Southern Ontario has recently been identified as a risk area for Echinococcus multilocularis, based on surveys of foxes (Vulpes vulpes) and coyotes (Canis latrans) which act as definitive hosts of the parasite. In this manuscript, we describe the first detection of E. multilocularis in an eastern chipmunk (Tamias striatus) in North America. This case, submitted to the Canadian Wildlife Health Cooperative (CWHC) in August 2016 as part of ongoing wildlife disease surveillance activities, represents the first report of alveolar echinococcosis in a wild, free living, intermediate host from southern Ontario, providing further evidence of an established sylvatic cycle of E. multilocularis in this region. The finding prompted a field investigation to identify additional cases of alveolar echinococcosis in small mammals in the summer of 2017. Echinococcus multilocularis was not detected in any of the 196 small mammals submitted to the CWHC from across southern Ontario or in any of the 43 small mammals trapped in the area where the infected chipmunk was found. However, given the suspected low prevalence and patchy distribution of E. multilocularis in small mammals, our negative results do not preclude the established presence of the parasite. This case emphasizes the importance of passive surveillance networks for monitoring new and emerging diseases in wildlife populations.


Subject(s)
Animals, Wild/parasitology , Echinococcosis/veterinary , Echinococcus multilocularis/isolation & purification , Sciuridae/parasitology , Animals , Canada/epidemiology , Echinococcosis/diagnosis , Echinococcosis/epidemiology , Feces/parasitology , Prevalence
SELECTION OF CITATIONS
SEARCH DETAIL
...