105 research outputs found
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Subjectivity in a context of environmental change: opening new dialogues in mental health research
In a period of unstable experimentation with challenges of globalization of associated risks, and disenchantment with ‘enduring injustice’, we bring forward a consideration of subjectivity to the study of environmental change and mental health. We begin by identifying how mainstream climate change and mental health studies are unable to explain the emergent and co-evolutionary pathways of agency. As a means of freeing these studies of their objective dimensions of linear-causation, we argue in favour of a re-positioning of subjectivity within an appreciation of recognition conflicts and beyond the over-deterministic interpretations of power centres—state, market or religion. We draw on one example of scientific research that was conducted in a region undergoing strong environmental, social and cultural changes, in the state of São Paulo/Brazil, with the aim to open mental health research to new dialogues, to which we contribute with the notion of the ‘pluriversal subject’
Environmental Education After Sustainability : Hope in the Midst of Tragedy
In this article, I discuss the challenge posed to environmental education (EE; and education for sustainable development) by the thinkers who see the situation of the world as so severe that ‘sustainability’ is an outdated concept. My approach is interdisciplinary and I discuss especially the connections between EE and eco-psychology. Based on psychological research, I argue that the wide-scale unconscious anxiety, which people experience, should be taken very seriously in EE. My discussion thus contributes in a new kind of way to a long-standing key issue in EE, the gap between people’s values and the perceived action. Scholars of eco-anxiety have argued that instead of not caring, many people in fact care too much, and have to resort to psychological defenses of denial and disavowal. Thus, the question in EE is not anymore whether EE should deal with anxiety, for anxiety is already there. The prevailing attitude in EE writing is right in emphasizing positive matters and empowerment, but the relation between hope and optimism must be carefully thought about and a certain sense of tragedy must be included. Therefore, my article participates in the discussion about the role of ‘fear appeals’ in EE. My discussion is directed to anyone who wants to understand the reasons for inaction and the ways in which these may be overcome.Peer reviewe
High Probability Ventilation-Perfusion Scan in Primary Pulmonary Hypertension
The perfusion lung scan is a valuable noninvasive tool in the evaluation of patients with pulmonary arterial hypertension of undetermined cause and for the exclusion of occult large-vessel pulmonary thromboembolism. Peripheral patchy defects have been reported in primary pulmonary hypertension (PPH) but there are no well documented reports of segmental or larger perfusion defects. A case of a 55-year-old male with severe pulmonary hypertension of unknown etiology who had persistent high probability perfusion scan patterns over a period of two years is reported. No evidence of thromboembolism was present on pulmonary angiography. A discussion of the case and a review of the literature on the role of lung scan in PPH are presented. Most patients with PPH have normal or low probability perfusion scans; high probability scans occur rarely
High Probability Ventilation-Perfusion Scan in Primary Pulmonary Hypertension
The perfusion lung scan is a valuable noninvasive tool in the evaluation of patients with pulmonary arterial hypertension of undetermined cause and for the exclusion of occult large-vessel pulmonary thromboembolism. Peripheral patchy defects have been reported in primary pulmonary hypertension (PPH) but there are no well documented reports of segmental or larger perfusion defects. A case of a 55-year-old male with severe pulmonary hypertension of unknown etiology who had persistent high probability perfusion scan patterns over a period of two years is reported. No evidence of thromboembolism was present on pulmonary angiography. A discussion of the case and a review of the literature on the role of lung scan in PPH are presented. Most patients with PPH have normal or low probability perfusion scans; high probability scans occur rarely.Peer Reviewe
Evolutionary opportunity and the limits of community similarity in replicate radiations of island lizards
Ecological community structure ultimately depends on evolution producing
community members. To understand how macroevolutionary processes shape
communities, we surveyed Anolis lizard assemblages across
elevations on Jamaica and Hispaniola, neighboring Caribbean islands
similar in environment, but contrasting in evolutionary richness. The
impact of diversification on local communities depends on available
opportunities for speciation within or between ecologically distinct
sub-regions. Where opportunities abound, as in the vast lowlands of both
islands, communities converge in species richness and average
morphology. But community structures diverge in the highlands. On
Jamaica, where limited highland area restricted diversification,
communities remain depauperate and consist largely of elevational
generalists. In contrast, a unique fauna of high-elevation specialists
evolved in the expansive Hispaniolan highlands, augmenting highland
richness, and driving islandwide turnover in community composition.
Accounting for disparate evolutionary opportunities may illuminate when
regional diversity will enhance local diversity and help identify the
causes of convergent versus divergent community structure.</jats:p
Dyspnea in Cancer Patients: Prevalence and Associated Factors
The objectives of this study were to determine the prevalence of dyspnea in the general cancer population, the intensity of the symptom as perceived by the patient, and the patient characteristics associated with the presence of dyspnea. Nine hundred and twenty-three cancer outpatients completed visual analogue scales (VAS) and verbal rating scales (VRS-D) to assess the intensity of their dyspnea. Baseline data included variables that were known covariates of dyspnea. Forty-six percent of the patients had some shortness of breath. Only 4% had a diagnosis of lung cancer and 5.4% lung metastases. Risk factors found to be significantly related to the presence of dyspnea were history of smoking; asthma or chronic obstructive pulmonary disease (COPD); lung irradiation; or a history of exposure to asbestos, coal dust, cotton dust or grain dust (P values from 0.001 to 0.038). The prevalence of dyspnea was strongly related to the number of risk factors a patient had (P < 0.0001). The VAS and VRS-D were significantly correlated, establishing concurrent validity for the VRS-D
Scaling of Natal Dispersal Distances in Terrestrial Birds and Mammals
Natal dispersal is a process that is critical in the spatial dynamics of populations, including population spread, recolonization, and gene flow. It is a central focus of conservation issues for many vertebrate species. Using data for 77 bird and 68 mammal species, we tested whether median and maximum natal dispersal distances were correlated with body mass, diet type, social system, taxonomic family, and migratory status. Body mass and diet type were found to predict both median and maximum natal dispersal distances in mammals: large species dispersed farther than small ones, and carnivorous species dispersed farther than herbivores and omnivores. Similar relationships occurred for carnivorous bird species, but not for herbivorous or omnivorous ones. Natal dispersal distances in birds or mammals were not significantly related to broad categories of social systems. Only in birds were factors such as taxonomic relatedness and migratory status correlated with natal dispersal, and then only for maximum distances. Summary properties of dispersal processes appeared to be derived from interactions among behavioral and morphological characteristics of species and from their linkages to the dynamics of resource availability in landscapes. In all the species we examined, most dispersers moved relatively short distances, and long-distance dispersal was uncommon. On the basis of these findings, we fit an empirical model based on the negative exponential distribution for calculating minimum probabilities that animals disperse particular distances from their natal areas. This model, coupled with knowledge of a species' body mass and diet type, can be used to conservatively predict dispersal distances for different species and examine possible consequences of large-scale habitat alterations on connectedness between populations. Taken together, our results can provide managers with the means to identify species vulnerable to landscape-level habitat changes such as forest fragmentation. In addition, our dispersal models can be used to predict which species in a community are likely to be the most vulnerable to loss of connectedness and allow managers to test the merits of alternative habitat conservation plans
Is ingestion of milk-associated bacteria by premature infants fed raw human milk controlled by routine bacteriologic screening?
Expressed human milk is often used to feed premature infants. Raw milk contains bacteria which may be a source of infection. Milk banks have developed screening programs which combine periodic quantitative milk cultures with arbitrary rules specifying limits of bacterial concentration. It is unknown whether such programs succeed in preventing infants from being fed milk containing bacteria. At the Health Sciences Centre (Winnipeg, Manitoba, Canada), milk is screened once weekly. When a woman's milk is found to have excess bacteria, it is discarded only if she is an unrelated donor (as opposed to an infant's mother). To assess the effectiveness of this screening program, we determined the frequency at which infants fed raw human milk were exposed to milk-associated bacteria and compared the bacterial contents of donor and maternal milk. From February 1986 to April 1987, all human milk fed to 98 premature infants during the first 2 weeks of feeding (n = 10,128 feeds) was cultured quantitatively. Among study infants, 100% were exposed at least once to coagulase-negative staphylococci, 41% were exposed to Staphylococcus aureus, and 64% were exposed to gram-negative bacilli. The proportions of feeds containing bacteria and the quantities (log10 CFU [mean +/- standard deviation]) ingested per positive feed were: 39% and 5.9 +/- 0.5 for coagulase-negative staphylococci; 2.4% and 5.1 +/- 1.0 for S. aureus; and 5.2% and 4.8 +/- 1.1 for gram-negative bacilli. There were no adverse events attributable to ingestion of milk-associated bacteria. Milk coagulase-negative staphylococcal isolates were multiply antibiotic susceptible, whereas infant isolates were antibiotic resistant. Donor milk was significantly less likely than maternal milk to contain coagulase-negative staphylococcal species in any quantity (40 versus 93% of samples, respectively [P < 0.001]) or in concentrations exceeding 10(8) CFU/liter (3 versus 27% of samples, respectively [P < 0.0001]). There was no difference between milk from either source in terms of S. aureus or gram-negative bacterial content (4 to 6%). These results suggest that the Health Sciences Centre screening program is effective in limiting the number of harmless coagulase-negative staphylococcal species but has no impact on the quantity of potentially pathogenic bacteria ingested by premature infants. Implications for screening donor milk are discussed.</jats:p
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