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Introduction: A critical component for successful implementation of any innovation is an organization's readiness for change. Competence by Design (CBD) is the Royal College's major change initiative to reform the training of medical specialists in Canada. The purpose of this study was to measure readiness to implement CBD among the 2019 launch disciplines. Methods: An online survey was distributed to program directors of the 2019 CBD launch disciplines one month prior to implementation. Questions were developed based on the R = MC2 framework for organizational readiness. They addressed program motivation to implement CBD, general capacity for change, and innovation-specific capacity. Questions related to motivation and general capacity were scored using a 5-point scale of agreement. Innovation-specific capacity was measured by asking participants whether they had completed 33 key pre-implementation tasks (yes/no) in preparation for CBD. Bivariate correlations were conducted to examine the relationship between motivation, general capacity and innovation specific capacity. Results: Survey response rate was 42% (n = 79). A positive correlation was found between all three domains of readiness (motivation and general capacity, r = 0.73, p < 0.01; motivation and innovation specific capacity, r = 0.52, p < 0.01; general capacity and innovation specific capacity, r = 0.47, p < 0.01). Most respondents agreed that successful launch of CBD was a priority (74%). Fewer felt that CBD was a move in the right direction (58%) and that implementation was a manageable change (53%). While most programs indicated that their leadership (94%) and faculty and residents (87%) were supportive of change, 42% did not have experience implementing large-scale innovation and 43% indicated concerns about adequate support staff. Programs had completed an average of 72% of pre-implementation tasks. No difference was found between disciplines (p = 0.11). Activities related to curriculum mapping, competence committees and programmatic assessment had been completed by >90% of programs, while <50% of programs had engaged off-service rotations. Conclusion: Measuring readiness for change aids in the identification of factors that promote or inhibit successful implementation. These results highlight several areas where programs struggle in preparation for CBD launch. Emergency medicine training programs can use this data to target additional implementation support and ongoing faculty development initiatives.
Few studies have been conducted looking at clinical features associated to treatment resistant depression (TRD) defined as failure to at least two consecutive antidepressant trials. The objective of this study was to identify clinical and demographic factors associated to TRD in a large sample of depressed patients who failed to reach response or remission after at least two consecutive adequate treatments.
A total of 702 patients with unipolar major depression were included in the analysis. 346 patients were considered as non resistant. The remaining 356 patients were considered as resistant with a HAM-D-17 score remaining ≥ 17 after 2 consecutive adequate trials. Cox regression models were used to examine the association between individual clinical variables and TRD.
Eleven variables were found to be associated with TRD. Anxiety comorbidity (p<0.001, OR=2.6), comorbid panic disorder (p<0.001, OR=2.6) and social phobia (p<0.008, OR=2.1), personality disorder (p<0.049, OR=1.7), suicidal risk (p<0.001, OR=2.2), severity (p<0.001, OR=1.7), melancholia (p<0.018, OR=1.5), a number of hospitalizations > 1 (p<0.003, OR=1.6), recurrent episodes (p<0.009, OR=1.5), early age of onset (p<0.009, OR=2.0) and non response to the first antidepressant received lifetime (p<0.019, OR=1.6).
Our findings provide a set of eleven relevant clinical variables associated to TRD which can be explored at the clinical level. The statistical model used in this analysis allowed for a hierarchy of these variables (based on the OR) showing that comorbid anxiety disorder is the most powerful clinical factor associated to TRD.
Reconstructions of prehistoric vegetation composition help establish natural baselines, variability, and trajectories of forest dynamics before and during the emergence of intensive anthropogenic land use. Pollen–vegetation models (PVMs) enable such reconstructions from fossil pollen assemblages using process-based representations of taxon-specific pollen production and dispersal. However, several PVMs and variants now exist, and the sensitivity of vegetation inferences to PVM selection, variant, and calibration domain is poorly understood. Here, we compare the reconstructions, parameter estimates, and structure of a Bayesian hierarchical PVM, STEPPS, both to observations and to REVEALS, a widely used PVM, for the pre–Euro-American settlement-era vegetation in the northeastern United States (NEUS). We also compare NEUS-based STEPPS parameter estimates to those for the upper midwestern United States (UMW). Both PVMs predict the observed macroscale patterns of vegetation composition in the NEUS; however, reconstructions of minor taxa are less accurate and predictions for some taxa differ between PVMs. These differences can be attributed to intermodel differences in structure and parameter estimates. Estimates of pollen productivity from STEPPS broadly agree with estimates produced for use in REVEALS, while comparison between pollen dispersal parameter estimates shows no significant relationship. STEPPS parameter estimates are similar between the UMW and NEUS, suggesting that STEPPS parameter estimates are transferable between floristically similar regions and scales.
The spatial distribution of basal water critically impacts the evolution of ice sheets. Current estimates of basal water distribution beneath the Greenland Ice Sheet (GrIS) contain large uncertainties due to poorly constrained boundary conditions, primarily from geothermal heat flux (GHF). The existing GHF models often contradict each other and implementing them in numerical ice-sheet models cannot reproduce the measured temperatures at ice core locations. Here we utilize two datasets of radar-detected basal water in Greenland to constrain the GHF at regions with a thawed bed. Using the three-dimensional ice-sheet model SICOPOLIS, we iteratively adjust the GHF to find the minimum GHF required to reach the bed to the pressure melting point, GHFpmp, at locations of radar-detected basal water. We identify parts of the central-east, south and northwest Greenland with significantly high GHFpmp. Conversely, we find that the majority of low-elevation regions of west Greenland and parts of northeast have very low GHFpmp. We compare the estimated constraints with the available GHF models for Greenland and show that GHF models often do not honor the estimated constraints. Our results highlight the need for community effort to reconcile the discrepancies between radar data, GHF models, and ice core information.
22q11.2 deletion syndrome (22q11DS), one of the most common recurrent copy number variant disorders, is associated with dopaminergic abnormalities and increased risk for psychotic disorders.
Given the elevated prevalence of substance use and dopaminergic abnormalities in non-deleted patients with psychosis, we investigated the prevalence of substance use in 22q11DS, compared with that in non-deleted patients with psychosis and matched healthy controls.
This cross-sectional study involved 434 patients with 22q11DS, 265 non-deleted patients with psychosis and 134 healthy controls. Psychiatric diagnosis, full-scale IQ and COMT Val158Met genotype were determined in the 22q11DS group. Substance use data were collected according to the Composite International Diagnostic Interview.
The prevalence of total substance use (36.9%) and substance use disorders (1.2%), and weekly amounts of alcohol and nicotine use, in patients with 22q11DS was significantly lower than in non-deleted patients with psychosis or controls. Compared with patients with 22q11DS, healthy controls were 20 times more likely to use substances in general (P < 0.001); results were also significant for alcohol and nicotine use separately. Within the 22q11DS group, there was no relationship between the prevalence of substance use and psychosis or COMT genotype. Male patients with 22q11DS were more likely to use substances than female patients with 22q11DS.
The results suggest that patients with 22q11DS are at decreased risk for substance use and substance use disorders despite the increased risk of psychotic disorders. Further research into neurobiological and environmental factors involved in substance use in 22q11DS is necessary to elucidate the mechanisms involved.
Background Attention-deficit/hyperactivity disorder (ADHD) is among the most common psychiatric disorders of childhood that often persists into adulthood and old age. Yet ADHD is currently underdiagnosed and undertreated in many European countries, leading to chronicity of symptoms and impairment, due to lack of, or ineffective treatment, and higher costs of illness.
Methods The European Network Adult ADHD and the Section for Neurodevelopmental Disorders Across the Lifespan (NDAL) of the European Psychiatric Association (EPA), aim to increase awareness and knowledge of adult ADHD in and outside Europe. This Updated European Consensus Statement aims to support clinicians with research evidence and clinical experience from 63 experts of European and other countries in which ADHD in adults is recognized and treated.
Results Besides reviewing the latest research on prevalence, persistence, genetics and neurobiology of ADHD, three major questions are addressed: (1) What is the clinical picture of ADHD in adults? (2) How should ADHD be properly diagnosed in adults? (3) How should adult ADHDbe effectively treated?
Conclusions ADHD often presents as a lifelong impairing condition. The stigma surrounding ADHD, mainly due to lack of knowledge, increases the suffering of patients. Education on the lifespan perspective, diagnostic assessment, and treatment of ADHD must increase for students of general and mental health, and for psychiatry professionals. Instruments for screening and diagnosis of ADHD in adults are available, as are effective evidence-based treatments for ADHD and its negative outcomes. More research is needed on gender differences, and in older adults with ADHD.
The use of assessment tools has been shown to improve the inter-rater reliability of capacity assessments. However, instrument-based capacity assessments of people with dementia face challenges. In dementia research, measuring capacity with instruments like the MacArthur Competence Assessment Tool for Treatment (MacCAT-T) mostly employ hypothetical treatment vignettes that can overwhelm the abstraction capabilities of people with dementia and are thus not always suitable for this target group. The primary aim of this study was to provide a standardized real informed consent paradigm that enables the dementia-specific properties of capacity to consent to treatment in people with dementia to be identified in a real informed consent process that is both externally valid and ethically justifiable.
The sample consisted of 53 people with mild to moderate dementia and a group of 133 people without cognitive impairment. Rather than using a hypothetical treatment vignette, we used a standardized version of the MacCAT-T to assess capacity to consent to treatment with cholinesterase inhibitors in people with dementia. Inter-rater reliability, item statistics, and psychometric properties were also investigated.
Intraclass correlations (ICCs) (0.951–0.990) indicated high inter-rater reliability of the standardized real informed consent paradigm. In the dementia group, performance on different items of the MacCAT-T varied. Most people with dementia were able to express a treatment choice, and were aware of the need to take a tablet. Further information on the course of the disorder and the benefits and risks of the treatment were less understood, as was comparative reasoning regarding treatment alternatives.
The standardized real informed consent paradigm enabled us to detect dementia-specific characteristics of patients’ capacity to consent to treatment with cholinesterase inhibitors. In order to determine suitable enhanced consent procedures for this treatment, we recommend the consideration of MacCAT-T results on an item level. People with dementia seem to understand only basic information. Our data indicate that one useful strategy to enhance capacity to consent is to reduce attention and memory demands as far as possible.
Ecological systems are extraordinarily complex. Thus classical approaches to resolve ecosystem functioning have simplified analyses by conceptualizing ecosystems as being organized into trophic level compartments that contain organisms with similar feeding dependencies (e.g., producers, herbivores, carnivores) (Elton, 1927; Lindeman, 1942). Two competing worldviews on the regulation of ecosystem productivity emanated from such a conceptualization of ecosystem structure. The bottom-up view posits that the productivity of each trophic level is essentially limited by the one immediately below it (Lindeman, 1942; Feeny, 1968), while the top-down view recognizes that resource levels influence production, but contends that herbivore populations are mostly limited by predators rather than producer biomass (Hairston et al., 1960). Accordingly, predators can indirectly increase the productivity of a given system by reducing the negative effects of herbivores on plant biomass, resulting in a world that is green with plant material, rather than denuded by herbivory (Paine, 1969; Oksanen et al., 1981). Bottom-up theory countered that the world is green not because of predators, but instead due to variation in plant quality as a result of anti-herbivore defenses or weather patterns (Murdoch, 1966; Ehrlich and Birch, 1967; Scriber and Feeny, 1975; White, 1978; Feeny, 1991; Polis and Strong, 1996). This variation causes much of the “green” world to be inedible to herbivores; thus herbivores are still resource-limited.
The recognition of context-dependence in the degree of top-down or bottom-up control of ecosystems has resulted in gradual changes in how ecosystem functioning is envisioned. For instance, the “exploitation ecosystems” hypothesis (EEH) addresses context-dependence by combining elements of top-down and bottom-up concepts (Oksanen et al., 1981; Oksanen and Oksanen, 2000). At low levels of soil resource availability, plants are not productive enough to support herbivore populations and are thus bottom-up controlled (see Fig. 5.3). At medium levels of soil resources, an ecosystem can support herbivore populations, which in turn control plant productivity, while carnivores enter the ecosystem and control the herbivore population at the highest resource availability, thus releasing plant productivity from herbivore control.
Introduced accidentally from South America, deeproot sedge is rapidly expanding in a variety of habitats throughout the southeastern United States. Of particular concern is its rapid expansion, naturalization, and formation of monocultures in Texas coastal prairie, one of the most imperiled temperate ecoregions in North America. The objective of this research was to examine how deeproot sedge responds to prescribed fire, to the herbicide imazapic, and to treatment combinations of both. Combinations of prescribed fire and imazapic treatments and imazapic-only treatments effectively reduced deeproot sedge cover and frequency. However, plots exposed to dormant season fires (with no imazapic) had greater deeproot sedge cover after burn treatments were applied, indicating that coastal prairie management using only dormant season prescribed fire will not work toward reduction or management of this exotic invasive species. Although deeproot sedge cover was often reduced in fire–imazapic treatment combinations, it was still present in treatment plots. Moreover, desirable functional plant groups (i.e., native bunchgrasses) did not respond positively to the fire–imazapic treatments, but in some instances, woody plant coverage increased. Repeated, long-term approaches using integrated and coordinated efforts with multiple treatment options will be necessary to restore community structure to desired compositional levels. Such integrated approaches should be effective in reducing deeproot sedge frequency, cover, and extent to more manageable levels throughout its introduced geographic range.
During 2007–2010, 13 545 confirmed human verocytotoxin (VT)-producing Escherichia coli (VTEC) infections were reported in the European Union, including 777 haemolytic uraemic syndrome (HUS) cases. Clinical manifestations were reported for 53% of cases, 64% of which presented with diarrhoea alone and 10% with HUS. Isolates from 85% of cases were not fully serotyped and could not be classified on the basis of the Karmali seropathotype concept. There is no single or combination of phenotypic or genetic marker(s) that fully define ‘pathogenic’ VTEC. Isolates which contain the vtx2 (verocytotoxin 2) gene in combination with the eae (intimin-encoding) gene or aaiC (secreted protein of enteroaggregative E. coli) and aggR (plasmid-encoded regulator) genes have been associated with a higher risk of more severe illness. A molecular approach targeting genes encoding VT and other virulence determinants is thus proposed to allow an assessment of the potential severity of disease that may be associated with a given VTEC isolate.
Native to temperate South America, deeproot sedge has naturalized throughout the southeastern United States. Often forming dense, homogenous stands, deeproot sedge has become widespread, invasive, and potentially harmful ecologically throughout the coastal prairie ecoregion of Texas. Possessing characteristics (rapid growth, generalized habitat requirements) of other weedy congeners (purple nutsedge and yellow nutsedge), its relatively recent expansion highlights the critical need to develop effective control techniques and strategies for this species throughout this endangered ecoregion. Research was performed to delineate total nonstructural carbohydrate (TNC) trends in deeproot sedge rhizomes for development of a phenologically based schedule for herbicide applications and mechanical treatments. Overall, TNC levels were greatest in May to August and lowest from October to January, regardless of study area. Apparently, deeproot sedge exerts little energy into seed production because TNC levels were continually replenished throughout the growing season. As such, foliar-herbicide application throughout the growing season should achieve total plant kill. Conversely, deeproot sedge rhizome TNC levels never fell below 30%, even during winter, which indicates that winter mechanical treatments or winter prescribed fires will not be effective because substantial rhizome reserves are present to support resprouting during the next growing season. Beyond a priori prevention, sequential herbicide applications combined with integrated, sequential, prescribed fire and herbicide treatments will be needed for long-term deeproot sedge control throughout its geographic range.
Phenotypic plasticity is a ubiquitous phenomenon in nature, and provides a basis for trait-mediated indirect interactions (TMIIs) among species in ecological communities. Since trait-mediated indirect effects (TMIEs) are replete across a wide range of ecosystems, it is becoming increasingly apparent that phenotypic plasticity in response to interacting species can play an important role in determining community organization and dynamics. Below we highlight the major findings of community consequences of TMIIs in this volume.
TMIIs are common and can determine trophic structure in marine pelagic and insect host–parasitoid systems, both of which have been little explored (Chapters 3 and 4).
TMIEs in prey–predator systems should be taken into consideration in terms of non-trophic links (Chapter 2), size- and age-structure of a population (Chapter 5) and density-dependence (Chapter 6).
Herbivore-caused phenotypic plasticity and/or genetic variations of plants have significant, indirect impacts on diversity and abundance of predators, and prey–predator interactions by bottom-up cascading effects (Chapters 7 and 9).
Community ecology is experiencing a resurgence, driven in part by its central importance in addressing critical applied problems, ranging from the control of pest and invasive species, to the wise harvest of natural resources, to projecting the impact of global climate change. A fundamental tenet of community ecology is that species do not exist in isolation: they are directly, and more importantly, indirectly interconnected with myriad other species. The essential ‘glue’ that holds communities together and that makes them more than the haphazard sum of individual species is the nexus of indirect interactions among three or more species that emerges from direct interactions such as predation, competition and mutualism between pairs of species. The recognition of indirect effects has triggered a rapid growth of empirical and theoretical research that aims to predict community-level dynamics under different contexts.
Indirect effects occur when the impacts of one species on another are influenced by one or more intermediate species. Indirect effects are diverse, but can be classified broadly as either (1) density-mediated or (2) trait-mediated. Density-mediated indirect effects (DMIEs) result from numerical responses of species to each other. For instance, a fox may kill rabbits, reducing rabbit population size, and so relaxing herbivory upon herbaceous plants. Hence, the fox’s indirect effect on plants is mediated by density changes in rabbits; this is known as a trophic cascade. DMIEs, such as depicted by this trophic cascade, and other mechanisms such as apparent competition between prey mediated by the numerical response of a shared predator, have been well studied and have contributed to our understanding of community organization and ecosystem functioning in both terrestrial and aquatic systems (Holt and Lawton 1994; Polis et al. 2000; Terborgh and Estes 2010). However, the fox may not only kill rabbits, it may alter their behaviour and other traits. For instance, rabbits may hide more in the presence of foxes and so have less opportunity to feed on herbs. This indirect effect of the fox upon the plants could be strong, even though rabbit abundance remains high in the presence of foxes. In this case, it is a change in a rabbit’s trait – altered behaviour to avoid predation – that determines the outcome of the predator–prey direct interaction and the nature of the indirect effect of foxes on plants.
An ecosystem is often defined simply as a community of organisms interacting with each other and their biophysical environment. This definition arose from early conceptions of how the natural world is organized and is elegant in its simplicity because it captures the basic elements of a functioning system (Tansley 1935; Leopold 1939; Lindeman 1942). But those trying to develop a synthetic, empirical understanding of how ecosystems function and how they will respond to environmental change are abundantly aware that there is much inherent complexity implied by this seemingly simple definition. To cope with this complexity, ecologists have traditionally abstracted one part of the definition and elaborated the other. For example, ecosystem ecologists have long assumed that interacting organisms can be simply assigned to different compartments (e.g., producer, primary and secondary consumer, decomposer) and focused on environmental and biophysical aspects that dictate the transformation and flow of materials and energy among various compartments (Lindeman 1942; Odum 1969; Likens et al. 1970). In contrast, community ecologists have downplayed the biophysical aspects of materials and energy transfer and focused on organismal populations (Shelford 1913; Elton 1927; Hutchinson 1957; Paine 1966; MacArthur 1972), their diversity and the myriad interactions (e.g., predation, competition, facilitation) that determine their distribution and abundance (Reiners 1986; DeAngelis 1992).
Modern efforts to integrate organismal and abiotic factors into the study of ecosystems arguably were inspired by Hairston, Slobodkin and Smith’s (HSS) classic paper (Hairston et al. 1960), which sought to merge Lindeman’s trophic dynamic perspective (Lindeman 1942) and MacArthur’s population ecology perspective (MacArthur 1958) to explain why, in the face of putatively abundant herbivores, the world is still largely green rather than denuded by herbivory. HSS made the simple argument that the world is green because predators limit the impact of herbivores on plants. This paper highlighted the ecological significance of indirect effects by viewing the biological component of ecosystems as being comprised of linear food chains where interacting species (who eats whom) determine the flow of materials and energy through the ecosystem (Paine 1988; Cohen et al. 1990).
Water-soluble Fe3O4@ZnO composite nanoparticles (NPs) were synthesized using a polyol route. The effects of the addition of the ZnO phase were evaluated by varying the Zn/Fe molar ratio in the 0.25-1.00 range as a function of the reaction time. X-ray diffractometry confirmed the formation of the magnetite and ZnO phases and suggested the possible formation of a composite structure. Also, using this method, pure magnetite and ZnO NPs were synthesized. The average crystallite sizes were estimated to 6.3 ± 0.3 nm and 8.6 ± 0.6 nm for magnetite and ZnO NPs, respectively. The samples were examined using transmission electron microscopy. Fourier transform infrared spectra indicated the presence of adsorbed species onto the solids surface, which may explain the good stability of the materials in water. Photoluminescence measurements at room temperature for pure ZnO nanoparticles exhibited the characteristic excitonic emission around 395 nm. Vibrating Sample Magnetometer measurements at room temperature evidenced the superparamagnetic behavior of magnetite nanocrystals, with a saturation magnetization of 60emu/g. The maximum magnetization ranged from 28 to 54emu/g for the composite NPs. Mössbauer spectroscopy measurements at room temperature showed evidence of evolving Fe-sites associated to superparamagnetic particles, as reflected on the coexistence of prominent doublet peaks and very weak sextet peaks.
The cycling behavior of anode materials based on alloys from the Li(Al1–zZnz) continuous solid solution has been studied. The performance of the most promising composition Li(Al0.8Zn0.2) was tested in half-cells against metallic Li with three different electrolytes and in full Li-ion cells against a V2O5 cathode. The underlying structure evolution during cycling and the most relevant fatigue mechanisms are elucidated by x-ray diffraction, nuclear magnetic resonance, and x-ray photoelectron spectroscopy, and reveal a loss of mobile Li due to the ongoing formation of solid electrolyte interfaces. An enhanced stability for Li(Al1–zZnz) electrodes with z˜0.2 results from a peculiar microstructure due to the decomposition of Al and Zn in the Li-poor state and their intermixing in the Li-rich state.