31 results
Search Results
2. Leafhoppers as vectors of phytoplasma diseases in Canadian berry crops: a review in the face of climate change.
- Author
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Santos, Abraão Almeida, Jacques, Jordanne, Plante, Nicolas, Fournier, Valérie, and Pérez-López, Edel
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PHYTOPLASMA diseases , *BERRIES , *LEAFHOPPERS , *DISEASE vectors , *CLIMATE change , *CITRUS greening disease - Abstract
Climate change has facilitated the introduction, establishment, and movement of invasive species in northern regions, enabling the colonization of previously unsuitable areas. While the responses of insects to these changes have been increasingly studied, our understanding of how such alterations impact trophic interactions still requires further research to make reliable predictions about the spread of diseases in a warming world. Phytoplasmas, a group of obligate parasitic unculturable Mollicutes, primarily rely on leafhoppers (Hemiptera: Cicadellidae) for transmission, spread, and survival. Phytoplasmas are associated with over 600 diseases affecting more than 1,000 plant species, including berries, grapevines, and other small fruits. In North America, diseases such as grapevine yellows, blueberry stunt, and strawberry green petal diseases have been linked to phytoplasma strains transmitted by known leafhopper species. However, the number of phytoplasma diseases has significantly increased in North America over the past decade, suggesting the presence of unidentified vectors or an abundance of leafhopper vectors. This short review provides an overview of the current knowledge on leafhoppers as vectors of phytoplasmas to berries, focusing on the last decade's research in Canada. This paper also explores the potential implications of climate change on this pathosystem, including the anticipated range expansion of leafhopper species, changes in phytoplasma acquisition and transmission, and the risk of new leafhopper-transmitted plant-pathogen introductions through the arrival of new leafhopper species. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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3. Diet selection in the Coyote Canis latrans.
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Hayward, Matt W, Mitchell, Carl D, Kamler, Jan F, Rippon, Paul, Heit, David R, Nams, Vilis, and Montgomery, Robert A
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PREDATION , *COYOTE , *WHITE-tailed deer , *MULE deer , *PREY availability , *DIET , *SPATIAL variation - Abstract
The Coyote (Canis latrans) is one of the most studied species in North America with at least 445 papers on its diet alone. While this research has yielded excellent reviews of what coyotes eat, it has been inadequate to draw deeper conclusions because no synthesis to date has considered prey availability. We accounted for prey availability by investigating the prey selection of coyotes across its distribution using the traditional Jacobs' index method, as well as the new iterative preference averaging (IPA) method on scats and biomass. We found that coyotes selected for Dall's Sheep (Ovis dalli), White-tailed Deer (Odocoileus virginianus), Eastern Cottontail Rabbit (Sylvilagus floridanus), and California Vole (Microtus californicus), which yielded a predator-to-preferred prey mass ratio of 1:2. We also found that coyotes avoided preying on other small mammals, including carnivorans and arboreal species. There was strong concordance between the traditional and IPA method on scats, but this pattern was weakened when biomass was considered. General linear models revealed that coyotes preferred to prey upon larger species that were riskier to hunt, reflecting their ability to hunt in groups, and were least likely to hunt solitary species. Coyotes increasingly selected Mule Deer (O. hemionus) and Snowshoe Hare (Lepus americanus) at higher latitudes, whereas Black-tailed Jackrabbit (L. californicus) were increasingly selected toward the tropics. Mule Deer were increasingly selected at higher coyote densities, while Black-tailed Jackrabbit were increasingly avoided at higher coyote densities. Coyote predation could constrain the realized niche of prey species at the distributional limits of the predator through their increased efficiency of predation reflected in increased prey selection values. These results are integral to improved understandings of Coyote ecology and can inform predictive analyses allowing for spatial variation, which ultimately will lead to better understandings about the ecological role of the coyote across different ecosystems. [ABSTRACT FROM AUTHOR]
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- 2023
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4. Temporal Trends of Infective Endocarditis in North America From 2000 to 2017—A Systematic Review.
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Talha, Khawaja M, Dayer, Mark J, Thornhill, Martin H, Tariq, Wajeeha, Arshad, Verda, Tleyjeh, Imad M, Bailey, Kent R, Palraj, Raj, Anavekar, Nandan S, Sohail, M Rizwan, DeSimone, Daniel C, and Baddour, Larry M
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DRUG abuse , *INFECTIVE endocarditis , *STAPHYLOCOCCUS aureus - Abstract
Background The objective of this paper was to examine temporal changes of infective endocarditis (IE) incidence and epidemiology in North America. Methods A systematic review was conducted at Mayo Clinic, Rochester. Ovid EBM Reviews, Ovid Embase, Ovid Medline, Scopus, and Web of Science were searched for studies published between January 1, 2000, and May 31, 2020. Four referees independently reviewed all studies, and those that reported a population-based incidence of IE in patients aged 18 years and older in North America were included. Results Of 8588 articles screened, 14 were included. Overall, IE incidence remained largely unchanged throughout the study period, except for 2 studies that demonstrated a rise in incidence after 2014. Five studies reported temporal trends of injection drug use (IDU) prevalence among IE patients with a notable increase in prevalence observed. Staphylococcus aureus was the most common pathogen in 7 of 9 studies that included microbiologic findings. In-patient mortality ranged from 3.7% to 14.4%, while the percentage of patients who underwent surgery ranged from 6.4% to 16.0%. Conclusions The overall incidence of IE has remained stable among the 14 population-based investigations in North America identified in our systematic review. Standardization of study design for future population-based investigations has been highlighted for use in subsequent systematic reviews of IE. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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5. Geodynamic models of short-lived, long-lived and periodic flat slab subduction.
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Schellart, W P and Strak, V
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SUBDUCTION , *SLABS (Structural geology) , *OCEANIC plateaus , *EOCENE Epoch , *SUBDUCTION zones - Abstract
Flat slab subduction has been ascribed to a variety of causes, including subduction of buoyant ridges/plateaus and forced trench retreat. The former, however, has irregular spatial correlations with flat slabs, while the latter has required external forcing in geodynamic subduction models, which might be insufficient or absent in nature. In this paper, we present buoyancy-driven numerical geodynamic models and aim to investigate flat slab subduction in the absence of external forcing as well as test the influence of overriding plate strength, subducting plate thickness, inclusion/exclusion of an oceanic plateau and lower mantle viscosity on flat slab formation and its evolution. Flat slab subduction is reproduced during normal oceanic subduction in the absence of ridge/plateau subduction and without externally forced plate motion. Subduction of a plateau-like feature, in this buoyancy-driven setting, enhances slab steepening. In models that produce flat slab subduction, it only commences after a prolonged period of slab dip angle reduction during lower mantle slab penetration. The flat slab is supported by mantle wedge suction, vertical compressive stresses at the base of the slab and upper mantle slab buckling stresses. Our models demonstrate three modes of flat slab subduction, namely short-lived (transient) flat slab subduction, long-lived flat slab subduction and periodic flat slab subduction, which occur for different model parameter combinations. Most models demonstrate slab folding at the 660 km discontinuity, which produces periodic changes in the upper mantle slab dip angle. With relatively high overriding plate strength or large subducting plate thickness, such folding results in periodic changes in the dip angle of the flat slab segment, which can lead to periodic flat slab subduction, providing a potential explanation for periodic arc migration. Flat slab subduction ends due to the local overriding plate shortening and thickening it produces, which forces mantle wedge opening and a reduction in mantle wedge suction. As overriding plate strength controls the shortening rate, it has a strong control on the duration of flat slab subduction, which increases with increasing strength. For the weakest overriding plate, flat slab subduction is short-lived and lasts only 6 Myr, while for the strongest overriding plate flat slab subduction is long-lived and exceeds 75 Myr. Progressive overriding plate shortening during flat slab subduction might explain why flat slab subduction terminated in the Eocene in western North America and in the Jurassic in South China. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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6. Early 20th century conceptualization of health promotion.
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Madsen, Wendy
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DISEASES , *HEALTH , *HEALTH education , *HEALTH promotion , *MATHEMATICAL models , *PUBLIC health , *TERMS & phrases , *THEORY , *HISTORY - Abstract
This historical analysis of the term 'health promotion' during the early 20th century in North American journal articles revealed concepts that strongly resonate with those of the 21st century. However, the lineage between these two time periods is not clear, and indeed, this paper supports contentions health promotion has a disrupted history. This paper traces the conceptualizations of health promotion during the 1920s, attempts to operationalize health promotion in the 1930s resulting in a narrowing of the concept to one of health education, and the disappearance of the term from the 1940s. In doing so, it argues a number of factors influenced the changing conceptualization and utilization of health promotion during the first half of the 20th century, many of which continue to present times, including issues around what health promotion is and what it means, ongoing tensions between individual and collective actions, tensions between specific and general causes of health and ill health, and between expert and societal contributions. The paper concludes the lack of clarity around these issues contributed to health promotion disappearing in the mid-20th century and thus resolution of these would be worth- while for the continuation and development of health promotion as a discipline into the 21st century. [ABSTRACT FROM AUTHOR]
- Published
- 2017
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7. Methods for the robust computation of the long-period seismic spectrum of broad-band arrays.
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Caton, Ross C, Pavlis, Gary L, Thomson, David J, and Vernon, Frank L
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FREE earth oscillations , *SEISMIC arrays , *T-test (Statistics) , *SOLAR oscillations , *FOURIER analysis , *SIGNAL-to-noise ratio , *SENSOR arrays - Abstract
We describe array methods to search for low signal-to-noise ratio (SNR) signals in long-period seismic data using Fourier analysis. This is motivated by published results that find evidence of solar free oscillations in the Earth's seismic hum. Previous work used data from only one station. In this paper, we describe methods for computing spectra from array data. Arrays reduce noise level through averaging and provide redundancy that we use to distinguish coherent signal from a random background. We describe two algorithms for calculating a robust spectrum from seismic arrays, an algorithm that automatically removes impulsive transient signals from data, a jackknife method for estimating the variance of the spectrum, and a method for assessing the significance of an entire spectral band. We show examples of their application to data recorded by the Homestake Mine 3-D array in Lead, SD and the Piñon Flats PY array. These are two of the quietest small aperture arrays ever deployed in North America. The underground Homestake data has exceptionally low noise, and the borehole sensors of the PY array also have very low noise, making these arrays well suited to finding very weak signals. We find that our methods remove transient signals effectively from the data so that even low-SNR signals in the seismic background can be found and tested. Additionally, we find that the jackknife variance estimate is comparable to the noise floor, and we present initial evidence for solar g-modes in our data through the T 2 test, a multivariate generalization of Student's t -test. [ABSTRACT FROM AUTHOR]
- Published
- 2020
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8. A new method to integrate different gravity gradient components in reweighted regularized inversion with a minimum support constraint.
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Qin, Pengbo, Xiang, Min, Liang, Xin, and Hou, Zhenlong
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SALT domes , *GRAVITY , *MATRIX inversion , *MATRIX effect , *GRAVITY anomalies , *ATHLETIC tape - Abstract
The gravity gradient tensor has been increasingly used in practical applications. Among them, how to extract information contained in different gravity gradient components is a challenging problem. Gravity gradient joint inversion is one effective method to solve this problem. We integrate different gravity gradient components in a matrix and then apply them in inversion directly. In this paper, we modify the method to get a new gravity gradient joint inversion (NGGJI). The method is based on the reweighted regularized inversion. We choose one component, for example, g zz, and use the other components to build a weighting matrix. Then we apply the weighting matrix in g zz inversion. We present the method to construct the weighting matrix based on a single component and multiple components. We analyse the characteristics of different weighting matrices and the noise effects on weighting matrices. We compare the inversion results obtained from the conventional gravity gradient joint inversion (CGGJI) with the inversion results obtained from the NGGJI. We conclude that the NGGJI's requirement for memory storage is lower and the resolution of the NGGJI inversion results is higher. We apply the method to survey data from Vinton Salt Dome, Louisiana, USA. The results have proved to be consistent with known geological information. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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9. The role of the North American Breeding Bird Survey in conservation.
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Hudson, Marie-Anne R., Francis, Charles M., Campbell, Kate J., Downes, Constance M., Smith, Adam C., and Pardieck, Keith L.
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BIRD surveys , *BIRD breeding , *WILDLIFE conservation , *BIRD populations , *GOLDEN eagle , *ENDANGERED species , *BIRD conservation - Abstract
The North American Breeding Bird Survey (BBS) was established in 1966 in response to a lack of quantitative data on changes in the populations of many bird species at a continental scale, especially songbirds. The BBS now provides the most reliable regional and continental trends and annual indices of abundance available for >500 bird species. This paper reviews some of the ways in which BBS data have contributed to bird conservation in North America over the past 50 yr, and highlights future program enhancement opportunities. BBS data have contributed to the listing of species under the Canadian Species at Risk Act and, in a few cases, have informed species assessments under the U.S. Endangered Species Act. By raising awareness of population changes, the BBS has helped to motivate bird conservation efforts through the creation of Partners in Flight. BBS data have been used to determine priority species and locations for conservation action at regional and national scales through Bird Conservation Region strategies and Joint Ventures. Data from the BBS have provided the quantitative foundation for North American State of the Birds reports, and have informed the public with regard to environmental health through multiple indicators, such as the Canadian Environmental Sustainability Indicators and the U.S. Environmental Protection Agency's Report on the Environment. BBS data have been analyzed with other data (e.g., environmental, land cover, and demographic) to evaluate potential drivers of population change, which have then informed conservation actions. In a few cases, BBS data have contributed to the evaluation of management actions, including informing the management of Mourning Doves (Zenaida macroura}, Wood Ducks (Aix sponsa}, and Golden Eagles (Aquila chrysaetos}. Improving geographic coverage in northern Canada and in Mexico, improving the analytical approaches required to integrate data from other sources and to address variation in detectability, and completing the database, by adding historical bird data at each point count location and pinpointing the current point count locations would further enhance the survey's value. [ABSTRACT FROM AUTHOR]
- Published
- 2017
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10. Implementing Security Council Resolutions in Hong Kong: An Examination of the United Nations Sanctions Ordinance.
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Cheng Yan Ki Bonnie
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SEPARATION of powers , *HUMAN rights ,UNITED Nations Security Council resolutions ,UNITED Nations sanctions - Abstract
The United Nations Sanctions Ordinance is the primary legal basis of the Hong Kong Special Administrative Region (HKSAR) for implementing the United Nations Security Council's resolutions. However, there are concerns that the Ordinance is potentially violating the separation of powers in its delegation of regulation-making authority to the executive. There are also criticisms against the expediency of the Ordinance as a mechanism lot enforcing Security Council sanctions. Against this background, this paper attempts to examine the separation of powers doctrine, its place in HKSAR's constitutional system and its relevance to the Ordinance. On the issue of expediency, this paper focuses on the scope and speed of implementing the sanctions, and the human rights and criminal justice pro blems it involves. For comparative purposes, references are to be made to the law of the USA, Canada and Singapore. [ABSTRACT FROM AUTHOR]
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- 2008
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11. Asylum: a perspective on current policy challenges.
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Appave, Gervaise
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POLITICAL refugees , *LEGAL status of refugees - Abstract
A conference paper about challenges being faced by policy makers with regards to asylum issues is presented. It discusses the development of asylum systems which started in the early nineties when there was an increase in asylum applications in Western Europe, Australia and North America. It highlights asylum policy challenges which include keeping the current asylum systems working, managing litigation, implementing return of asylum seekers, bridging the gap in protection gap, and looking for alternatives to asylum.
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- 2001
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12. The importance of interactions between patients and healthcare professionals for heart failure self-care: A systematic review of qualitative research into patient perspectives.
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Currie, Kay, Strachan, Patricia H., Spaling, Melisa, Harkness, Karen, Barber, David, and Clark, Alexander M.
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HEART failure treatment , *CAREGIVERS , *COMMUNICATION , *CONTINUUM of care , *CRITICAL theory , *MEDICAL personnel , *PATIENT-professional relations , *RESEARCH funding , *HEALTH self-care , *SYSTEMATIC reviews , *QUALITATIVE research , *SOCIAL support , *META-synthesis - Abstract
Background: Effective heart failure (HF) self-care can improve clinical outcomes but is dependent on patients’ undertaking a number of complex self-care behaviors. Research into the effectiveness of HF management programs demonstrates mixed results. There is a need to improve understanding of patient perspectives’ of self-care need in order to enhance supportive interventions. Aim: This paper reports selected findings from a systematic review of qualitative research related to HF self-care need from the patients’ perspective. The focus here is on those facets of patient-healthcare professional relationships perceived by patients to influence HF self-care. Method: We searched multiple healthcare databases to identify studies reporting qualitative findings with extractable data related to HF self-care need. Joanna Briggs Institute systematic review methods were employed and recognized meta-synthesis techniques were applied. Critical realist theory provided analytical direction to highlight how individual and contextual factors came together in complex ways to influence behavior and outcomes. Results: Altogether 24 studies (1999–2012) containing data on patient-healthcare professional relationships and HF self-care were included. Interaction with healthcare professionals influenced self-care strongly but was notably mixed in terms of reported quality. Effective HF self-care was more evident when patients perceived that their healthcare professional was responsive, interested in their individual needs, and shared information. Poor communication and lack of continuity presented common barriers to HF self-care. Conclusion: Interactions and relationships with clinicians play a substantial role in patients’ capacity for HF self-care. The way healthcare professionals interact with patients strongly influences patients’ understanding about their condition and self-care behaviors. [ABSTRACT FROM AUTHOR]
- Published
- 2015
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13. Urban forests and solar power generation: partners in urban heat island mitigation.
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Staley, Daniel C.
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URBAN forestry , *SOLAR power plants , *URBAN heat islands , *SUSTAINABLE architecture , *ECOSYSTEM services - Abstract
The urban forest is generally decreasing in areal extent. At the same time, human population is urbanizing and urban areal extent per capita is increasing. Eighty percent of North Americans are now living in urbanized areas. Urban forests directly affect quality of life for residents of cities via the ecosystem services and psychosocial restoration they provide. The urban forest canopy is a key component of reducing the urban heat island, slowing stormwater runoff and making urban environments more efficient and livable. Municipalities in North America are reacting to concerns about urbanization and economic trends by permitting an increasing number of compact developments that may conflict with beneficial Green Infrastructure. Compact development may also present challenges to solar access for solar power generation. This paper identifies and illustrates key strategies to increase urban forest cover and decrease infrastructure conflicts by implementing given innovative design details, detailing specific zoning and code language, and providing best practices from multiple disciplines. These strategies to increase urban forest canopy cover frame a coherent set of ideas to decrease the effects of the urban heat island, increase solar power generation and improve urban quality of life in cities. [ABSTRACT FROM PUBLISHER]
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- 2015
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14. THE NORTHERN FLYING SQUIRREL: BIOLOGICAL PORTRAIT OF A FOREST SPECIALIST IN POST-EUROPEAN SETTLEMENT NORTH AMERICA.
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Smith, Winston P.
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NORTHERN flying squirrel , *GLAUCOMYS , *TAIGAS , *FOREST conservation , *CONFERENCES & conventions - Abstract
Papers in this Special Feature were presented at a symposium on the biology of Glaucomys sabrinus convened at the 86th Annual Meeting of the American Society of Mammalogists in June 2006. Because G. sabrinus is an arboreal species that relies on several attributes of older forests, it is an ideal model organism for studying impacts of broad-scale habitat loss and alteration from logging, clearing, and natural disturbances. The objective of the symposium was to integrate knowledge of mammalogists from multiple disciplines to achieve a more complete biological portrait to gain insights about how forest communities are being impacted by dramatic changes in forest composition and distribution following European settlement of North America, and to identify gaps in knowledge and information needs that can guide future research. The symposium included 5 papers that encompass a diversity of biological information, including the evolutionary origin and systematics of Glaucomys, the anatomy and evolution of G. sabrinus, its biogeography, genetic variation within and among regional populations, its ecology, functional morphology, kinetics, and issues and challenges of conservation. [ABSTRACT FROM AUTHOR]
- Published
- 2007
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15. Aging in Culture.
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Fung, Helene H.
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AGE distribution , *AGING , *CHINESE people , *COGNITION , *CULTURE , *DEVELOPMENTAL psychobiology , *INTERPERSONAL relations , *LIFE , *CULTURAL values , *LABELING theory - Abstract
This paper is a based on the Baltes Award Lecture given at the Annual Meeting of The Gerontological Society of America held in Boston, Massachusetts, in November, 2011.This article reviews the empirical studies that test socioemotional aging across cultures. The review focuses on comparisons between Western (mostly North Americans and Germans) and Eastern cultures (mostly Chinese) in areas including age-related personality, social relationships, and cognition. Based on the review, I argue that aging is a meaning-making process. Individuals from each cultural context internalize cultural values with age. These internalized cultural values become goals that guide adult development. When individuals from different cultures each pursue their own goals with age, cultural differences in socioemotional aging occur. [ABSTRACT FROM PUBLISHER]
- Published
- 2013
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16. Living well in care homes: a systematic review of qualitative studies.
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Bradshaw, Siobhan Aine, Playford, E. Diane, and Riazi, Afsane
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PATIENT satisfaction , *ADAPTABILITY (Personality) , *CARING , *CINAHL database , *DECISION making , *MEDICAL information storage & retrieval systems , *PSYCHOLOGY information storage & retrieval systems , *MEDICAL quality control , *MEDLINE , *NURSING home patients , *LEGAL status of patients , *QUALITY of life , *RESEARCH funding , *SYSTEMATIC reviews , *QUALITATIVE research , *THEMATIC analysis - Abstract
Background: research in care home settings is often negatively focused, portraying life as sterile and devoid of meaningful experiences. Care homes have the potential to influence people's lives socially, physically and psychologically. It is important to understand what factors contribute to this.Objective: to conduct a systematic qualitative review of care home life and provide practical recommendations to enhance residents' quality of life.Methods: the following databases were searched: PsycINFO, Medline, Web of Science, EMBASE, Allied and Complementary Medicine Database and Cumulative Index to Nursing and Allied Health Literature. References from appropriate journals and individual articles were checked. Papers that fitted our selection criteria were selected. Two independent reviewers assessed methodological study quality. Thematic analysis and meta-ethnographic methods were adapted to synthesise findings.Results: thirty-one studies were identified. People in care homes voiced concerns about lack of autonomy and difficulty in forming appropriate relationships with others. Four key themes were identified: (i) acceptance and adaptation, (ii) connectedness with others, (iii) a homelike environment, (iv) caring practices.Conclusion: positive experiences in care homes can occur and are important for residents' quality of life. The review supports literature highlighting the need for relationship-centred approaches to care and emphasises the importance of understanding the resident's attitude towards living in care homes. [ABSTRACT FROM AUTHOR]
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- 2012
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17. Preparing ESP Learners for workplace placement.
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Wood, David
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ENGLISH as a foreign language , *FOREIGN engineering students , *JOB qualifications , *CERTIFICATION , *FLUENCY (Language learning) - Abstract
Engineering students in North American universities often participate in cooperative education placements in workplaces as part of the requirements for their degrees and professional certification. Students for whom English is an L2 often experience difficulties in these placements due to the fact that while their academic language ability may be sufficient to manage their coursework, they struggle to cope with the communication demands of a workplace context. This paper is a report of a course designed to assist these types of students in augmenting their workplace communication abilities. Students were required to analyse the fluency features and formulaic language of native speaker (NS) models of speech in genres relevant to the professional workplace and to conduct ethnographic research and analysis with NSs in face-to-face communication on similar themes. Results of the course show that fluency and proficiency in general were improved for the majority of the students. [ABSTRACT FROM PUBLISHER]
- Published
- 2009
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18. Assessment of systematic errors in the surface gravity anomalies over North America using the GRACE gravity model.
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Huang, J., Véronneau, M., and Mainville, A.
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GRAVIMETRY , *ERROR analysis in mathematics , *ARTIFICIAL satellites , *SPECTRUM analysis - Abstract
The surface gravity data collected via traditional techniques such as ground-based, shipboard and airborne gravimetry describe precisely the local gravity field, but they are often biased by systematic errors. On the other hand, the spherical harmonic gravity models determined from satellite missions, in particular, recent models from CHAMP and GRACE, homogenously and accurately describe the low-degree components of the Earth's gravity field. However, they are subject to large omission errors. The surface and satellite gravity data are therefore complementary in terms of spectral composition. In this paper, we aim to assess the systematic errors of low spherical harmonic degrees in the surface gravity anomalies over North America using a GRACE gravity model. A prerequisite is the extraction of the low-degree components from the surface data to make them compatible with GRACE data. Three types of methods are tested using synthetic data: low-pass filtering, the inverse Stokes integral, and spherical harmonic analysis. The results demonstrate that the spherical harmonic analysis works best. Eighty-five per cent of difference between the synthetic gravity anomalies generated from EGM96 and GGM02S from degrees 2 to 90 can be modelled for a region covering North America and neighbouring areas. Assuming EGM96 is developed solely from the surface gravity data with the same accuracy and GGM02S errorless, one way to understand the 85 per cent difference is that it represents the systematic error from the region of study, while the remaining 15 per cent originates from the data outside of the region. To estimate systematic errors in the surface gravity data, Helmert gravity anomalies are generated from both surface and GRACE data on the geoid. Their differences are expanded into surface spherical harmonics. The results show that the systematic errors for degrees 2 to 90 range from about −6 to 13 mGal with a RMS value of 1.4 mGal over North America. A few significant data gaps can be identified from the resulting error map. The errors over oceans appear to be related to the sea surface topography. These systematic errors must be taken into consideration when the surface gravity data are used to validate future satellite gravity missions. [ABSTRACT FROM AUTHOR]
- Published
- 2008
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19. Pinned on Karma Rock: Whitewater Kayaking as Religious Experience.
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Sanford, A. Whitney
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RELIGIOUS experience , *WHITEWATER kayaking , *RITUAL , *HOLY, The , *RELIGIOUS studies , *RELIGION - Abstract
This paper argues that whitewater paddling constitutes religious experience, that non-western terms often best describe this experience and that these two facts are related and have much to tell us about the nature of religious experience. That many paddlers articulate their experiences using Asian and/or indigenous religious terms suggests that this language is a form of opposition to existing norms of what constitutes religious experience. So, investigating the sport as an aquatic nature religion provides the opportunity to revisit existing categories. As a "lived religion," whitewater kayaking is a ritual practice of an embodied encounter with the sacred, and the sacred encounter is mediated through the body's performance in the water. This sacred encounter—with its risk and danger—illustrates Rudolph Otto's equation of the sacred with terrifying and unfathomable mystery and provides a counterpoint to norms of North American religiosity and related scholarship. [ABSTRACT FROM AUTHOR]
- Published
- 2007
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20. Carbon dioxide as a natural refrigerant.
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Cavallini, Alberto and Zilio, Claudio
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CARBON dioxide , *REFRIGERANTS , *CARBON compounds , *ATMOSPHERIC carbon dioxide - Abstract
In the beginnings of mechanical refrigeration, at the end of the nineteenth century, carbon dioxide was one of the first refrigerants to be used in compression-type refrigerating machines, later gaining widespread application mainly onboard refrigerated ships, but common in other sectors of refrigeration as well. It was only immediately after World War II that CO2 was rapidly eclipsed as a refrigerant, due to the advent of the synthesised halogenated working fluids, addressed as safe and ideal refrigerants at that time. Because of the stratospheric Ozone depletion environmental issue, CFC and HCFC working fluids are now in the process of being phased out of use under the Montreal Protocol. The Global Warming environmental issue casts concern over the use of the new HFC fluids as substitute refrigerants, because of their high GWP values, which make them subject to regulations under the Kyoto Protocol. In this mixed situation, CO2 is being revisited as a fully environmentally friendly and safe refrigerant. An intense research activity on its prospective applications is underway in many research establishments in Europe, Japan and North America, and important results have already been reached in exploiting the peculiar characteristics of this high-pressure fluid operated with a transcritical cycle. In some applications CO2 systems have already been commercialised; this applies to heat pump water heaters, as a brine in indirect systems and in the low temperature stage of cascade systems. The paper critically analyses the prospects for the future return of CO2 as a working fluid, or sometimes as a brine with change of phase, in important application areas. These include air conditioning and heat pump systems in the residential and commercial sectors, commercial and transport refrigeration and mobile air conditioning. [ABSTRACT FROM AUTHOR]
- Published
- 2007
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21. From Wage Slaves to Wage Workers: Cultural Opportunity Structures and the Evolution of the Wage Demands of the Knights of Labor and the American Federation of Labor, 1880-1900.
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Hallgrimsdottir, Helga Kristin and Benoit, Cecilia
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LABOR movement , *SOCIAL movements , *WAGES , *SOCIAL history , *ASSOCIATIONS, institutions, etc. , *SOCIAL forces , *SOCIAL change , *WAGE differentials - Abstract
This paper examines the reasons behind a historic shift in the language couching the wage demands of two North American labor movements during the last twenty years of the 19th century -- the Knights of Labor and the American Federation of Labor. We trace how the once dominant imagery of "wage slavery" lost its connection to producerist labor ideology and eventually was replaced by the more progmatic symbolism of "wage work." This linguistic shift is of particular scholarly importance because it occurred during a time when producerist labor politics, with its emphasis on a radical reorganization of work and private property, lost significant ground to a more consumerist/economistic version of labor politics. We show that this pivotal rhetorical shift was linked to changes in tire cultural opportunity structure. These were, in turn, shaped through movement sector dynamics and through changes in the empirical referents which add meaning and resonance to social movement claims. [ABSTRACT FROM AUTHOR]
- Published
- 2007
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22. Molecular methods used in clinical laboratory: prospects and pitfalls.
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Morshed, Muhammad G., Lee, Min-Kuang, Jorgensen, Danielle, and Isaac-Renton, Judith L.
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HUMAN fingerprints , *PATHOLOGICAL laboratories , *BORRELIA burgdorferi , *TREPONEMA pallidum , *WEST Nile virus - Abstract
The role of molecular detection, identification and typing or fingerprinting of microorganisms has shifted gradually from the academic world to the routine diagnostic laboratory. Molecular methods have been used increasingly over the past decade to improve the sensitivity, specificity and turn-around time in the clinical laboratory. Molecular methods have also been used to identify new and nonculturable agents. Many high-throughput molecular tests are now available commercially, which impacts on the infrastructure in many of the diagnostic laboratories. In this paper, we take an overall look at the use of molecular methods (prospects vs. pitfalls) based on our clinical and public health experience, particularly as they related to Borrelia burgdorferi, a vector-borne pathogen, Treponema pallidum, a re-emerging sexually transmitted global pathogen, and West Nile virus, a newly recognized virus in North America. [ABSTRACT FROM AUTHOR]
- Published
- 2007
- Full Text
- View/download PDF
23. Incorporating Allelic Variation for Reconstructing the Evolutionary History of Organisms from Multiple Genes: An Example from Rosa in North America.
- Author
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Joly, Simon and Bruneau, Anne
- Subjects
- *
PHYLOGENY , *TREES , *GENES , *ALGORITHMS - Abstract
Allelic variation within individuals holds information regarding the relationships of organisms, which is expected to be particularly important for reconstructing the evolutionary history of closely related taxa. However, little effort has been committed to incorporate such information for reconstructing the phylogeny of organisms. Haplotype trees represent a solution when one nonrecombinant marker is considered, but there is no satisfying method when multiple genes are to be combined. In this paper, we propose an algorithm that converts a distance matrix of alleles to a distance matrix among organisms. This algorithm allows the incorporation of allelic variation for reconstructing the phylogeny of organisms from one or more genes. The method is applied to reconstruct the phylogeny of the seven native diploid species of Rosa sect. Cinnamomeae in North America. The glyceralgehyde 3-phosphate dehydrogenase ( GAPDH ), the triose phosphate isomerase ( TPI ), and the malate synthase ( MS ) genes were sequenced for 40 individuals from these species. The three genes had little genetic variation, and most species showed incomplete lineage sorting, suggesting these species have a recent origin. Despite these difficulties, the networks (NeighborNet) of organisms reconstructed from the matrix obtained with the algorithm recovered groups that more closely match taxonomic boundaries than did the haplotype trees. The combined network of individuals shows that species west of the Rocky Mountains, Rosa gymnocarpa and R. pisocarpa , form exclusive groups and that together they are distinct from eastern species. In the east, three groups were found to be exclusive: R. nitida – R. palustris , R. foliolosa , and R. blanda – R. woodsii . These groups are congruent with the morphology and the ecology of species. The method is also useful for representing hybrid individuals when the relationships are reconstructed using a phylogenetic network. [Allelic variation; gene tree–species tree; haplotype trees; hybridization; incomplete lineage sorting; phylogenetic networks; Rosa ; total evidence.] [ABSTRACT FROM AUTHOR]
- Published
- 2006
- Full Text
- View/download PDF
24. Antimicrobial Prophylaxis for Surgery: An Advisory Statement from the National Surgical Infection Prevention Project.
- Author
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Bratzler, Dale W. and Houck, Peter M.
- Subjects
- *
INFECTION , *ANTI-infective agents , *SURGERY , *PREOPERATIVE care , *DOSAGE forms of drugs - Abstract
In January 2003, leadership of the Medicare National Surgical Infection Prevention Project hosted the Surgical Infection Prevention Guideline Writers Workgroup (SIPGWW) meeting. The objectives were to review areas of agreement among the most-recently published guidelines for surgical antimicrobial prophylaxis, to address inconsistencies, and to discuss issues not currently addressed. The participants included authors from most of the groups that have published North American guidelines for antimicrobial prophylaxis, as well as authors from several specialty colleges. Nominal group process was used to draft a consensus paper that was widely circulated for comment. The consensus positions of SIPGWW include that infusion of the first antimicrobial dose should begin within 60 mm before surgical incision and that prophylactic antimicrobials should be discontinued within 24 h after the end of surgery. This advisory statement provides an overview of other issues related to antimicrobial prophylaxis, including specific suggestions regarding antimicrobial selection. [ABSTRACT FROM AUTHOR]
- Published
- 2004
25. Is rangeland agriculture sustainable? 1, 2.
- Subjects
- *
RANGE management , *SUSTAINABLE agriculture , *POPULATION , *ECOLOGY , *ECOSYSTEMS , *SOCIAL impact , *RANGELANDS - Abstract
The objective of this paper is to examine the sustainability of rangeland agriculture (i.e., managed grazing) on a world-wide basis, with a focus on North America. Sustainability is addressed on three fronts: 1) ecological, 2) economic, and 3) social acceptance. Based on previous and on-going research, we suggest that employment of science-based rangeland grazing management strategies and tactics can ensure ecological sustainability. The formidable challenge in employing such technology centers around the need to balance efficiency of solar energy capture and subsequent harvest efficiencies across an array of highly spatially and temporally variable vegetation growing conditions using animals that graze selectively. Failure to meet this fundamental challenge often accelerates rangeland desertification processes, and in some instances, enhances rate and extent of the invasion of noxious weeds. We also suggest that the fundamental reason that ecologically sound grazing management technologies are often not employed in the management of grazed ecological systems is because social values drive management decisions more so than ecological science issues. This is true in both well-developed societies with substantial economic resources and in less-developed societies with few economic resources. However, the social issues driving management are often entirely different, ranging from multiple-use issues in developed countries to human day-to-day survival issues in poorly developed countries. We conclude that the long-term sustainability of rangeland agriculture in 1) developed societies depends on the ability of rangeland agriculturalists to continually respond in a dynamic, positive, proactive manner to ever-changing social values and 2) less-developed societies on their ability to address the ecological and social consequences arising from unsustainable human populations before the adoption of science-based sustainable rangeland management technologies. [ABSTRACT FROM AUTHOR]
- Published
- 2004
- Full Text
- View/download PDF
26. The Transformation of Policing? Understanding Current Trends in Policing Systems.
- Author
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Jones, Trevor and Newburn, Tim
- Subjects
- *
PRESSURE groups , *CRIMINAL justice system , *LAW enforcement - Abstract
This paper considers David Bayley and Clifford Shearing's (1996) argument that policing systems in developed economies are currently undergoing radical change. It is clear that a number of significant shifts have occurred including major reforms in public policing, and a substantial expansion of the private security industry. However, we question the degree to which current developments in policing should be interpreted as a sharp qualitative break with the past. By focusing primarily upon change the risk is that we overlook the significant consistencies and continuities that are equally important in understanding historical trends. We also question the extent to which the developments highlighted within this transformation thesis can be seen as global. We argue that the transformation thesis fails to take sufficient account of important differences between the nature and form of policing in North America, and of that in other countries such as Britain. We conclude by arguing that it is helpful to locate the set of changes within the framework of policing in a wider context. Thus, rather than view current developments as a fragmentation of policing, we see them as part of a long-term process of formalizaton of social control. The key development that appears to have taken place concerns shifts between what we term primary and secondary social control activities. [ABSTRACT FROM AUTHOR]
- Published
- 2002
- Full Text
- View/download PDF
27. Non-communicable diseases in migrants: an expert review.
- Author
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Agyemang, Charles and van den Born, Bert-Jan
- Subjects
- *
NON-communicable diseases , *EMIGRATION & immigration , *IMMIGRANTS , *MIGRANT agricultural workers , *HIGH-income countries , *CANCER-related mortality , *CARDIOVASCULAR diseases , *DIABETES , *TUMORS , *WORLD health - Abstract
Background: Non-communicable diseases (NCDs) remain a major challenge in the 21st century. High-income countries (HICs) populations are ethnically and culturally diverse due to international migration. Evidence suggests that NCDs rates differ between migrants and the host populations in HICs. This paper presents a review of NCDs burden among migrant groups in HICs in Europe, North America and Australia with a major focus on cardiovascular diseases (CVDs), cancer and diabetes.Methods: We performed a narrative review consisting of scholarly papers published between 1960 until 2018.Results: CVD risk differs by country of origin, country of destination and duration of residence. For example, stroke is more common in sub-Sahara African and South-Asian migrants, but lower in North African and Chinese migrants. Chinese migrants, however, have a higher risk of haemorrhagic stroke despite the lower rate of overall stroke. Coronary heart disease (CHD) is more common in South-Asian migrants, but less common in sub-Saharan and north African migrants although the lower risk of CHD in these population is waning. Diabetes risk is higher in all migrants and migrants seem to develop diabetes at an earlier age than the host populations. Migrants in general have lower rates of overall cancer morbidity and mortality than the host populations in Europe. However, migrants have a higher infectious disease-related cancers than the host populations in Europe. In North America, the picture is more complex. Data from cross-national comparisons indicate that migration-related lifestyle changes associated with the lifestyle of the host population in the country of settlement may influence NCDs risk among migrants in a very significant way.Conclusion: With exception of diabetes, which is consistently higher in all migrant groups than in the host populations, the burden of NCDs among migrants seems to depend on the migrant group, country of settlement and NCD type. This suggests that more work is needed to disentangle the key migration-related lifestyle changes and contextual factors that may be driving the differential risk of NCDs among migrants in order to assist prevention and clinical management of NCDs in these populations. [ABSTRACT FROM AUTHOR]- Published
- 2019
- Full Text
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28. Catholic Social Justice and Health Care Entitlement Packages.
- Author
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Boyle, Joseph
- Subjects
- *
SOCIAL justice -- Religious aspects , *MEDICAL care & religion , *HEALTH services accessibility , *EQUALITY , *CHRISTIANITY ,RELIGIOUS aspects - Abstract
This paper explores the implications of Roman Catholic teachings on social justice and rights to health care. It argues that contemporary societies, such as those in North America and Western Europe, have an obligation to provide health care to their citizens as a matter of right. Moral considerations provide a basis for evaluating concerns about the role of equality when determining health care entitlements and giving some precision to the widespread belief that the right to health care requires equal entitlement to health care benefits. [ABSTRACT FROM AUTHOR]
- Published
- 1996
- Full Text
- View/download PDF
29. Anti-Modernism, Modernism, and Postmodernism: Struggling with the Cultural Significance of New Religious Movements.
- Author
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Dawson, Lorne L.
- Subjects
- *
MODERNISM (Christian theology) , *RELIGION & sociology , *RELIGIOUS life , *RELIGIOUS movements , *SOCIAL movements - Abstract
Is the emergence of new forms of religious life in North America indicative of significant changes in the nature and role of religion in our society or changes in the character of our culture as a whole? Calling on a divergent array of theoretical frameworks sociologists have recurrently sought to explain the broader implications of the study of NRMs by aligning them, in whole or in part, with various perceived anti-modernist, modernist, and post-modernist tendencies in our society. In a critical overview of some of this disparate literature, this paper argues that certain unnoticed convergences in the positions taken, point to a reading of the cultural significance of NRMs that transcends the inaccurate tendency to identify NRMs too exclusively with one side of various essentially invidious dichotomies (e.g., pre-modern and modem, anti-modern and modem, conservative and liberal, modem and post-modem). [ABSTRACT FROM AUTHOR]
- Published
- 1998
- Full Text
- View/download PDF
30. The spirit of St Louis: the contributions of Lee N. Robins to North American psychiatric epidemiology.
- Author
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Campbell, Nancy D
- Subjects
- *
PSYCHIATRIC epidemiology , *THEORY of knowledge , *DRUG addiction - Abstract
This article takes up the history of North American psychiatric epidemiology with reference to production of knowledge concerning sociopathic or antisocial personality disorder and drug dependence, abuse, and/or addiction. These overlapping arenas provide a microcosm within which to explore the larger shift of postwar psychiatric epidemiology from community studies based on psychological scales to studies based on specific diagnostic criteria. This paper places the figure of sociologist Lee Nelken Robins within the context of the Department of Psychiatry in the School of Medicine at Washington University in St Louis, Missouri. The St Louis research group—to which Robins was both marginal and central—developed the basis for specific diagnostic criteria and was joined by Robert Spitzer, Jean Endicott and other architects of DSM-III in reorienting American psychiatry towards medical, biological and epidemiological models. Robins was a key linchpin working at the nexus of the psychiatric epidemiological and sociological drug addiction research networks. This article situates her work within the broader set of societal and governmental transformations leading to the technologically sophisticated turn in American psychiatric epidemiology and research on the aetiology of drug abuse and mental health and illness. [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
- View/download PDF
31. The World Health Organization and the contested beginnings of psychiatric epidemiology as an international discipline: one rope, many strands.
- Author
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Lovell, Anne M.
- Subjects
- *
PSYCHIATRIC epidemiology , *MENTAL health , *HEALTH programs , *SCHIZOPHRENIA - Abstract
This paper focuses on the relatively late emergence of psychiatric epidemiology as an international discipline, through local-global exchanges during the first 15 years of the World Health Organization (WHO). Building an epidemiological canon within WHO’s Mental Health Programme faced numerous obstacles. First, an idealist notion of mental health inherent in WHO’s own definition of health contributed to tensions around the object of psychiatric epidemiology. Second, the transfer of methods from medical epidemiology to research on mental disorders required mobilizing conceptual justifications, including a ‘contagion argument’. Third, epidemiological research at WHO was stymied by other public health needs, resource scarcity and cultural barriers. This history partly recapitulates the development of psychiatric epidemiology in North America and Europe, but is also shaped by concerns in the developing world, translated through first-world ‘experts’. Resolving the tensions arising from these obstacles allowed WHO to establish its international schizophrenia research, which in turn provided proof of concept for psychiatric epidemiology in the place of scepticism within and without psychiatry. [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
- View/download PDF
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