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1.
Biol Lett ; 19(10): 20230142, 2023 10.
Article in English | MEDLINE | ID: mdl-37875159

ABSTRACT

Body-size relationships between predators and prey exhibit remarkable diversity. However, the assumption that predators typically consume proportionally smaller prey often underlies size-dependent predation in ecosystem models. In reality, some animals can consume larger prey or exhibit limited changes in prey size as they grow larger themselves. These distinct predator-prey size relationships challenge the conventional assumptions of traditional size-based models. Cephalopods, with their diverse feeding behaviours and life histories, offer an excellent case study to investigate the impact of greater biological realism in predator-prey size relationships on energy flow within a size-structured ecosystem model. By categorizing cephalopods into high and low-activity groups, in line with empirically derived, distinct predator-prey size relationships, we found that incorporating greater biological realism in size-based feeding reduced ecosystem biomass and production, while simultaneously increasing biomass stability and turnover. Our results have broad implications for ecosystem modelling, since distinct predator-prey size relationships extend beyond cephalopods, encompassing a wide array of major taxonomic groups from filter-feeding fishes to baleen whales. Incorporating a diversity of size-based feeding in food web models can enhance their ecological and predictive accuracy when studying ecosystem dynamics.


Subject(s)
Ecosystem , Food Chain , Animals , Biomass , Body Size , Feeding Behavior , Predatory Behavior , Models, Biological
2.
Ecol Appl ; : e2772, 2022 Oct 31.
Article in English | MEDLINE | ID: mdl-36316814

ABSTRACT

Elucidating processes and mechanisms involved in rapid local adaptation to varied environments is a poorly understood but crucial component in management of invasive species. Recent studies have proposed that genetic and epigenetic variation could both contribute to ecological adaptation, yet it remains unclear on the interplay between these two components underpinning rapid adaptation in wild animal populations. To assess their respective contributions to local adaptation, we explored epigenomic and genomic responses to environmental heterogeneity in eight recently colonized ascidian (Ciona intestinalis) populations at a relatively fine geographical scale. Based on MethylRADseq data, we detected strong patterns of local environment-driven DNA methylation divergence among populations, significant epigenetic isolation by environment (IBE), and a large number of local environment-associated epigenetic loci. Meanwhile, multiple genetic analyses based on single nucleotide polymorphisms (SNPs) showed genomic footprints of divergent selection. In addition, for five genetically similar populations, we detected significant methylation divergence and local environment-driven methylation patterns, indicating the strong effects of local environments on epigenetic variation. From a functional perspective, a majority of functional genes, Gene Ontology (GO) terms, and biological pathways were largely specific to one of these two types of variation, suggesting partial independence between epigenetic and genetic adaptation. The methylation quantitative trait loci (mQTL) analysis showed that the genetic variation explained only 18.67% of methylation variation, further confirming the autonomous relationship between these two types of variation. Altogether, we highlight the complementary interplay of genetic and epigenetic variation involved in local adaptation, which may jointly promote populations' rapid adaptive capacity and successful invasions in different environments. The findings here provide valuable insights into interactions between invaders and local environments to allow invasive species to rapidly spread, thus contributing to better prediction of invasion success and development of management strategies.

3.
Biol Bull ; 242(2): 153-171, 2022 04.
Article in English | MEDLINE | ID: mdl-35580029

ABSTRACT

AbstractThe set of four closely related solitary ascidians Ciona spp. were once considered a single cosmopolitan species, Ciona intestinalis, but are now recognized as genetically and morphologically distinct species. The possibility of ecological differences between the species was not widely considered in studies preceding the schism of Ciona spp. Consequently, there may be an over-generalization of the ecology of Ciona spp., with potential implications for the broad range of studies targeting these species, encompassing the evolution, development, genomics, and invasion biology of Ciona spp. We completed a comprehensive review of the ecology of Ciona spp. to establish the similarities and differences between the widely distributed Ciona robusta and C. intestinalis (and what little is known of the two other species, Ciona sp. C and Ciona sp. D). When necessary, we used study locations and the species' geographic ranges to infer the species in each study in the review. As expected, ecological similarities are the norm between the two species, spanning both abiotic and biotic interactions. However, there are also important differences that have potential implications for other aspects of the biology of Ciona spp. For example, differences in temperature and salinity tolerances likely correspond with the disparities in the geographic distribution of the species. Asymmetries in topics studied in each species diminish our ability to fully compare several aspects of the ecology of Ciona spp. and are priority areas for future research. We anticipate that our clarification of common and unique aspects of each species' ecology will help to provide context for future research in many aspects of the biology of Ciona spp.


Subject(s)
Ciona intestinalis , Ciona , Animals , Ciona intestinalis/genetics , Genomics
5.
J Anim Ecol ; 89(11): 2692-2703, 2020 11.
Article in English | MEDLINE | ID: mdl-32895913

ABSTRACT

Individual body size strongly influences the trophic role of marine organisms and the structure and function of marine ecosystems. Quantifying trophic position-individual body size relationships (trophic allometries) underpins the development of size-structured ecosystem models to predict abundance and the transfer of energy through ecosystems. Trophic allometries are well studied for fishes but remain relatively unexplored for cephalopods. Cephalopods are important components of coastal, oceanic and deep-sea ecosystems, and they play a key role in the transfer of biomass from low trophic positions to higher predators. It is therefore important to resolve cephalopod trophic allometries to accurately represent them within size-structured ecosystem models. We assessed the trophic positions of cephalopods in an oceanic pelagic (0-500 m) community (sampled by trawling in a cold-core eddy in the western Tasman Sea), comprising 22 species from 12 families, using bulk tissue stable isotope analysis and amino acid compound-specific stable isotope analysis. We assessed whether ontogenetic trophic position shifts were evident at the species-level and tested for the best predictor of community-level trophic allometry among body size, taxonomy and functional grouping (informed by fin and mantle morphology). Individuals in this cephalopod community spanned two trophic positions and fell into three functional groups on an activity level gradient: low, medium and high. The relationship between trophic position and ontogeny varied among species, with the most marked differences evident between species from different functional groups. Activity-level-based functional group and individual body size are best explained by cephalopod trophic positions (marginal R2  = 0.43). Our results suggest that the morphological traits used to infer activity level, such as fin-to-mantle length ratio, fin musculature and mantle musculature are strong predictors of cephalopod trophic allometries. Contrary to established theory, not all cephalopods are voracious predators. Low activity level cephalopods have a distinct feeding mode, with low trophic positions and little-to-no ontogenetic increases. Given the important role of cephalopods in marine ecosystems, distinct feeding modes could have important consequences for energy pathways and ecosystem structure and function. These findings will facilitate trait-based and other model estimates of cephalopod abundance in the changing global ocean.


Subject(s)
Cephalopoda , Ecosystem , Animals , Aquatic Organisms , Food Chain , Nutritional Status , Oceans and Seas
6.
Br J Radiol ; 93(1110): 20190632, 2020 Jun.
Article in English | MEDLINE | ID: mdl-32108517

ABSTRACT

Elder abuse is an underdetected, under-reported issue with severe consequences. Its detection presents unique challenges based on characteristics of this vulnerable population, including cognitive impairment, age-related deconditioning, and an increased number of co-morbidities, all of which predispose to increase vulnerability to injury. While radiologists play a critical role in detection of child abuse, this role is currently not paralleled in detection of elder abuse. We conducted a thorough review of the literature using MEDLINE to describe the current knowledge on injury patterns and injury findings seen in elder abuse, as well as barriers to and recommendations for an increased role of diagnostic imaging in elder abuse detection. Barriers limiting the role of radiologists include lack of training and paucity of rigorous systematic research delineating distinctive imaging findings for physical elder abuse. We outline the current ways in which imaging can help raise clinical suspicion for elder abuse, including inconsistencies between purported mechanism of injury and imaging findings, injury location, multiple injuries at differing stages of healing, and particular patterns of injury likely to be intentionally inflicted. We additionally outline the mechanism by which medical education and clinical workflow may be modified to increase the role for imaging and radiologist participation in detecting abuse in older adult patients, and identify potential future directions for further systematic research.


Subject(s)
Elder Abuse/diagnosis , Wounds and Injuries/diagnostic imaging , Aged , Elder Abuse/statistics & numerical data , Female , Humans , Middle Aged , Tomography, X-Ray Computed , Wounds and Injuries/classification
8.
Can Assoc Radiol J ; 68(2): 171-177, 2017 May.
Article in English | MEDLINE | ID: mdl-28438284

ABSTRACT

The management of low back pain should always start with a conservative approach; however, when it fails, intervention is required and at that moment the most appropriate choice remains unclear. Before invasive surgery, minimally invasive techniques can be adopted. In European trials and in a trans-Canadian clinical trial 03 ozone has been used successfully. In total over 50,000 patients have been treated safely. Ozone is a gas normally present in the atmosphere with potent oxidizing power; it has been used for percutaneous intradiscal injection combined with oxygen (O2O3) at very low concentrations for 15 years in Europe. The main indication is back pain with or without radicular pain but without motor deficits, which is refractory to 4-6 weeks of conservative therapies. Its mechanism of action on the disc is mechanical (volume reduction by subtle dehydration of the nucleus pulposis) and antinflammatory. The intradiscal ozone injection is performed with a thin needle (18-22 gauge) image guided by computed tomography or angiofluoroscopy and is usually complimented by periganglionic injection of corticosteroids and anesthetics. This combination gives immediate pain relief and allows time for the ozone to act. It is a cost-effective procedure that presents a very low complication rate (0.1%). The radicular pain is resolved before the back pain does, as is seen with microdiscectomy. Peer-reviewed publications of large randomized trials, case series, and meta analysis from large samples of patients have demonstrated the procedure to be safe and effective in the short and the long terms, with benefits recognized up to 10 years after treatment. We aim to review the principles of action of O2O3 and report the injection techniques, complications, and short- and long-term outcomes.


Subject(s)
Low Back Pain/drug therapy , Oxygen/administration & dosage , Ozone/administration & dosage , Drug Combinations , Humans , Injections, Intralesional/methods , Intervertebral Disc Displacement/complications , Low Back Pain/etiology , Time Factors , Treatment Outcome
9.
Can Assoc Radiol J ; 68(2): 97, 2017 May.
Article in English | MEDLINE | ID: mdl-28438286

Subject(s)
Radiology/trends
12.
J Vasc Interv Radiol ; 28(3): 412-419, 2017 Mar.
Article in English | MEDLINE | ID: mdl-28111197

ABSTRACT

In the high-volume and increasingly complex world of image-guided therapy and medical imaging, awareness of the potential risks secondary to occupational radiation exposure in medical professionals needs greater focus. One of these risks is radiation-induced cataracts, a recently recognized entity, which may impact the physician's professional proficiency, quality of life, and career span. This review article aims to explain the pathogenesis of radiation-induced cataracts, exploring emerging evidence regarding their development. It also explores the existing monitoring and protection measures available to protect against such radiation-induced pathologic conditions.


Subject(s)
Cataract/etiology , Occupational Exposure/adverse effects , Occupational Health , Radiation Dosage , Radiation Exposure/adverse effects , Radiation Injuries/etiology , Radiography, Interventional/adverse effects , Cataract/diagnosis , Cataract/prevention & control , Humans , Occupational Exposure/prevention & control , Radiation Exposure/prevention & control , Radiation Injuries/diagnosis , Radiation Injuries/prevention & control , Radiation Monitoring/methods , Radiation Protection/methods , Risk Assessment , Risk Factors
13.
Can Assoc Radiol J ; 68(2): 187-193, 2017 May.
Article in English | MEDLINE | ID: mdl-27745988

ABSTRACT

Imaging techniques frequently employ contrast agents to improve image resolution and enhance pathology detection. These gadolinium- and iodine-based media, although generally considered safe, are associated with a number of adverse effects ranging from mild to severe. Reactions are classified as either anaphylactoid ("anaphylaxis-like") or nonanaphylactoid, depending on a number of elements that will be reviewed. Herein, we have summarized predisposing risk factors for adverse events resulting from the use of contrast, their associated pathophysiological mechanisms as well as known prophylaxis for the antitreatment of high-risk patients. In the unlikely event that a serious adverse reaction does occur, we have provided a comprehensive summary of treatment protocols. Our goal was to thoroughly evaluate the current literature regarding adverse reactions to radiocontrast agents and provide an up to date review for the health care provider.


Subject(s)
Contrast Media/adverse effects , Diagnostic Imaging , Canada , Drug-Related Side Effects and Adverse Reactions/etiology , Drug-Related Side Effects and Adverse Reactions/therapy , Humans , Risk Factors
14.
Can Assoc Radiol J ; 68(1): 16-20, 2017 Feb.
Article in English | MEDLINE | ID: mdl-27745989

ABSTRACT

PURPOSE: Emergency department assessment represents a critical but often missed opportunity to identify elder abuse, which is common and has serious consequences. Among emergency care providers, diagnostic radiologists are optimally positioned to raise suspicion for mistreatment when reviewing imaging of geriatric injury victims. However, little literature exists describing relevant injury patterns, and most radiologists currently receive neither formal nor informal training in elder abuse identification. METHODS: We present 2 cases to begin characterisation of the radiographic findings in elder abuse. RESULTS: Findings from these cases demonstrate similarities to suspicious findings in child abuse including high-energy fractures that are inconsistent with reported mechanisms and the coexistence of acute and chronic injuries. Specific injuries uncommon to accidental injury are also noted, including a distal ulnar diaphyseal fracture. CONCLUSIONS: We hope to raise awareness of elder abuse among diagnostic radiologists to encourage future large-scale research, increased focus on chronic osseous findings, and the addition of elder abuse to differential diagnoses.


Subject(s)
Diagnostic Imaging , Elder Abuse/diagnosis , Emergency Service, Hospital , Physician's Role , Radiologists , Aged, 80 and over , Diagnosis, Differential , Female , Geriatric Assessment , Humans
17.
J Vasc Interv Radiol ; 25(2): 171-81, 2014 Feb.
Article in English | MEDLINE | ID: mdl-24325929
18.
J Vasc Interv Radiol ; 24(7): 931-7, 2013 Jul.
Article in English | MEDLINE | ID: mdl-23796080

ABSTRACT

PURPOSE: To investigate the nature of inventiveness among members of the Society of Interventional Radiology (SIR) and learn what influenced the inventors and assisted their creativity. MATERIALS AND METHODS: The membership directory of the SIR was cross-referenced with filings at the United States Patent and Trademark Organization (USPTO) and the Patent Cooperation Treaty (PCT). The inventors were queried with an online survey to illuminate their institutions of training and practice as well as enabling or inhibiting factors to their inventiveness. Responses were analyzed through the construction of social network maps and thematic and graphical analysis. RESULTS: It was found that 457 members of the SIR held 2,492 patents or patent filings. After 1986, there was a marked and sustained increase in patent filings. The online survey was completed by 73 inventors holding 470 patents and patent filings. The social network maps show the key role of large academic interventional radiology departments and individual inventors in the formation of interconnectivity among inventors and the creation of the intellectual property (IP). Key inhibitors of the inventive process include lack of mentorship, of industry contacts, and of legal advice. Key enablers include mentorship, motivation, and industry contacts. CONCLUSIONS: Creativity and inventiveness in SIR members stem from institutions that are hubs of innovation and networks of key innovators; inventors are facilitated by personal motivation, mentorship, and strong industry contacts.


Subject(s)
Diffusion of Innovation , Inventions , Inventors , Radiography, Interventional/methods , Radiology, Interventional/methods , Social Networking , Societies, Medical , Cooperative Behavior , Creativity , Humans , Intellectual Property , Interdisciplinary Communication , Interinstitutional Relations , Inventors/psychology , Mentors , Motivation , Patents as Topic , Surveys and Questionnaires , United States
19.
AJNR Am J Neuroradiol ; 34(4): E0, 2013 Apr.
Article in English | MEDLINE | ID: mdl-23696968

ABSTRACT

PURPOSE: In this international multispecialty document, quality benchmarks for processes of care and clinical outcomes are defined. It is intended that these benchmarks be used in a quality assurance program to assess and improve processes and outcomes in acute stroke revascularization. MATERIALS AND METHODS: Members of the writing group were appointed by the American Society of Neuroradiology, Canadian Interventional Radiology Association, Cardiovascular and Interventional Radiological Society of Europe, Society of Cardiac Angiography and Interventions, Society of Interventional Radiology, Society of Neuro Interventional Surgery, European Society of Minimally Invasive Neurological Therapy, and Society of Vascular and Interventional Neurology. The writing group reviewed the relevant literature from 1986 through February 2012 to create an evidence table summarizing processes and outcomes of care. Performance metrics and thresholds were then created by consensus. The guideline was approved by the sponsoring societies. It is intended that this guideline be fully updated in 3 years. RESULTS: In this international multispecialty document, quality benchmarks for processes of care and clinical outcomes are defined. These include process measures of time to imaging, arterial puncture, and revascularization and measures of clinical outcome up to 90 days. CONCLUSIONS: Quality improvement guidelines are provided for endovascular acute ischemic stroke revascularization procedures.

20.
Catheter Cardiovasc Interv ; 82(2): E52-68, 2013 Aug 01.
Article in English | MEDLINE | ID: mdl-23640740

ABSTRACT

PURPOSE: In this international multispecialty document, quality benchmarks for processes of care and clinical outcomes are defined. It is intended that these benchmarks be used in a quality assurance program to assess and improve processes and outcomes in acute stroke revascularization. MATERIALS AND METHODS: Members of the writing group were appointed by the American Society of Neuroradiology, Canadian Interventional Radiology Association, Cardiovascular and Interventional Radiological Society of Europe, Society of Cardiac Angiography and Interventions, Society of Interventional Radiology, Society of NeuroInterventional Surgery, European Society of Minimally Invasive Neurological Therapy, and Society of Vascular and Interventional Neurology. The writing group reviewed the relevant literature from 1986 through February 2012 to create an evidence table summarizing processes and outcomes of care. Performance metrics and thresholds were then created by consensus. The guideline was approved by the sponsoring societies. It is intended that this guideline be fully updated in 3 years. RESULTS: In this international multispecialty document, quality benchmarks for processes of care and clinical outcomes are defined. These include process measures of time to imaging, arterial puncture, and revascularization and measures of clinical outcome up to 90 days. CONCLUSIONS: Quality improvement guidelines are provided for endovascular acute ischemic stroke revascularization procedures.


Subject(s)
Brain Ischemia/therapy , Endovascular Procedures/standards , Fibrinolytic Agents/administration & dosage , Quality Improvement/standards , Quality Indicators, Health Care/standards , Stroke/therapy , Thrombolytic Therapy/standards , Benchmarking/standards , Brain Ischemia/diagnosis , Consensus , Endovascular Procedures/adverse effects , Fibrinolytic Agents/adverse effects , Humans , Infusions, Intra-Arterial , Predictive Value of Tests , Stroke/diagnosis , Thrombolytic Therapy/adverse effects , Time Factors , Treatment Outcome
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