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1.
Korean J Med Educ ; 33(4): 393-404, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34875155

RESUMO

The required adjustments precipitated by the coronavirus disease 2019 crisis have been challenging, but also represent a critical opportunity for the evolution and potential disruptive and constructive change of medical education. Given that the format of medical education is not fixed, but malleable and in fact must be adaptable to societal needs through ongoing reflexivity, we find ourselves in a potentially transformative learning phase for the field. An Association for Medical Education in Europe ASPIRE Academy group of 18 medical educators from seven countries was formed to consider this opportunity, and identified critical questions for collective reflection on current medical education practices and assumptions, with the attendant challenge to envision the future of medical education. This was achieved through online discussion as well as asynchronous collective reflections by group members. Four major themes and related conclusions arose from this conversation: Why we teach: the humanitarian mission of medicine should be reinforced; what we teach: disaster management, social accountability and embracing an environment of complexity and uncertainty should be the core; how we teach: open pathways to lean medical education and learning by developing learners embedded in a community context; and whom we teach: those willing to take professional responsibility. These collective reflections provide neither fully matured digests of the challenges of our field, nor comprehensive solutions; rather they are offered as a starting point for medical schools to consider as we seek to harness the learning opportunities stimulated by the pandemic.


Assuntos
COVID-19 , Educação Médica , Humanos , Pandemias , SARS-CoV-2 , Faculdades de Medicina
2.
Case Rep Gastrointest Med ; 2019: 2789031, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31223508

RESUMO

Chicken bone ingestion is a common occurrence that usually passes uneventfully through the digestive tract and rarely results in complications such as perforation, which occurs very rarely within the stomach. We report here a case of a chicken bone ingestion resulting in gastric perforation, which ultimately required surgical correction.

3.
Teach Learn Med ; 31(1): 76-86, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30321063

RESUMO

PROBLEM: The traditional clerkship model of brief encounters between faculty and students results in reduced meaningful learning opportunities due to the lack of a relationship that enables repeated observation, supervisor feedback, trust formation, and growth. INTERVENTION: Clinical clerkships at our institution were restructured to decrease fragmentation of supervision and foster an educational alliance between faculty and student. A mixed-methods approach was used to study the impact of this curriculum reform on the student experience in the obstetrics and gynecology clerkship. Student participation in patient care was assessed by comparing the number of common obstetric procedures performed before and after clerkship reform. Separate qualitative analyses of comments from student surveys and a faculty focus group revealed themes impacting student involvement. The supervisor-trainee relationship was further investigated by analysis of "rich picture" discussions with students and faculty. CONTEXT: Clerkships in the 3rd year of our 4-year undergraduate medical curriculum were converted from an experience fragmented by both didactic activities and multiple faculty supervisors to one with a single supervisor and the elimination of competing activities. OUTCOMES: Students in the revised clerkship performed twice the number of obstetric procedures. Objective measures (United States Medical Licensing Examination Step 1 scores, receiving clerkship honors, self-reported interest in obstetrics, and gender) did not correlate with the number of procedures performed by students. Qualitative analysis of student survey comments revealed that procedure numbers were influenced by being proactive, having a supervisor with a propensity to teach (trust), and contextual factors (busy service or competition with other learners). Themes identified by faculty that influenced student participation included relationship continuity; growth of patient care skills; and observed student engagement, interest, and confidence. The quality of the relationship was cited by both students and faculty as a factor influencing meaningful clinical participation. Discussions of "rich pictures" drawn by students and faculty revealed that relationships are influenced by continuity, early alignment of goals, and the engagement and attitude of both student and faculty. LESSONS LEARNED: Clinical curricular reforms that strengthen the continuity of the supervisor-trainee relationship promote mutual trust and can result in a more meaningful training experience in less time. Reciprocal engagement and early alignment of goals between supervisor and trainee are critical for creating a positive relationship.


Assuntos
Estágio Clínico , Currículo , Relações Interprofissionais , Educação de Graduação em Medicina , Grupos Focais , Ginecologia/educação , Humanos , Obstetrícia/educação , Unidade Hospitalar de Ginecologia e Obstetrícia , Inquéritos e Questionários , Estados Unidos
4.
Ann Intern Med ; 168(8): SS1, 2018 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-29677276
5.
Teach Learn Med ; 30(4): 404-414, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29630412

RESUMO

Construct: The Empathy, Spirituality, and Wellness in Medicine Scale (ESWIM) is a 43-item multidimensional scale developed to investigate different dimensions of physicians and medical students. Background: Medical education research requires the use of several different instruments with dozens of items that evaluate each construct separately, making their application slow and increasing the likelihood of students providing a large number of incomplete or missing responses. To provide an alternative measure, this study aims to translate, adapt, and validate the multidimensional ESWIM instrument for Brazilian medical students. This is a very promising instrument because it is multidimensional, relatively short, and cost free; it evaluates important constructs; and it has been explicitly designed for use in the medical context. Approach: The English-language instrument was translated and adapted into the Brazilian Portuguese language using standard procedures: translation, transcultural adaptation, and back-translation. ESWIM was administered to students in all years of the medical curriculum. A retest was given 45 days later to evaluate reliability. To assess validity, the questionnaire also included sociodemographic data, the Duke Religion Index, the Empathy Inventory, the brief version of the World Health Organization Quality of Life (WHOQOL-Bref), and the Oldenburg Burnout Inventory. Results: A total of 776 medical students (M age = 22.34 years, SD = 3.11) were assessed. The Brazilian Portuguese version of ESWIM showed good internal consistency for the factor of Empathy (α = 0.79-0.81) and borderline internal consistency for the other factors: Openness to Spirituality (α = 0.61-0.66), Wellness (α = 0.57-0.68), and Tolerance (α = 0.56-0.65). The principal component analysis revealed a four-factor structure; however, the confirmatory factor analysis showed a better fit for a three-factor structure. We found a significant positive correlation between ESWIM empathy and empathy measured by the Empathy Inventory (r = .444, p < .01), as well as negative correlations between ESWIM empathy and burnout (r = -.145 to -.224, p < .01). ESWIM openness to spirituality was also significantly correlated with different subscales of religiosity (r = .301-.417, p < .01), and ESWIM wellness was significantly correlated with the WHOQOL-Bref factors (r = .390-.673, p < .01). The test-retest reliability (applied to 83 students) was high for all factors except Tolerance. Conclusion: This study provides supportive evidence regarding the reliability and validity of ESWIM empathy scores. The ESWIM scale opens a new field of research in relation to openness to spirituality by introducing a scale that measures this openness attitude. Despite borderline internal consistency, ESWIM wellness was strongly associated with quality of life and had good test-retest reliability. Thus, ESWIM appears to be a valid option for evaluating these constructs in medical students.


Assuntos
Competência Cultural , Empatia , Médicos/psicologia , Espiritualidade , Estudantes de Medicina/psicologia , Inquéritos e Questionários/normas , Adolescente , Adulto , Brasil , Análise Fatorial , Feminino , Humanos , Masculino , Adulto Jovem
6.
Acad Psychiatry ; 42(1): 62-67, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28861884

RESUMO

OBJECTIVE: This study aimed to compare mental health, quality of life, empathy, and burnout in medical students from a medical institution in the USA and another one in Brazil. METHODS: This cross-cultural study included students enrolled in the first and second years of their undergraduate medical training. We evaluated depression, anxiety, and stress (DASS 21), empathy, openness to spirituality, and wellness (ESWIM), burnout (Oldenburg), and quality of life (WHOQOL-Bref) and compared them between schools. RESULTS: A total of 138 Brazilian and 73 US medical students were included. The comparison between all US medical students and all Brazilian medical students revealed that Brazilians reported more depression and stress and US students reported greater wellness, less exhaustion, and greater environmental quality of life. In order to address a possible response bias favoring respondents with better mental health, we also compared all US medical students with the 50% of Brazilian medical students who reported better mental health. In this comparison, we found Brazilian medical students had higher physical quality of life and US students again reported greater environmental quality of life. Cultural, social, infrastructural, and curricular differences were compared between institutions. Some noted differences were that students at the US institution were older and were exposed to smaller class sizes, earlier patient encounters, problem-based learning, and psychological support. CONCLUSION: We found important differences between Brazilian and US medical students, particularly in mental health and wellness. These findings could be explained by a complex interaction between several factors, highlighting the importance of considering cultural and school-level influences on well-being.


Assuntos
Esgotamento Profissional/psicologia , Comparação Transcultural , Empatia , Saúde Mental , Qualidade de Vida/psicologia , Estudantes de Medicina/psicologia , Ansiedade , Brasil , Estudos Transversais , Depressão/psicologia , Feminino , Humanos , Masculino , Estresse Psicológico/psicologia , Inquéritos e Questionários , Estados Unidos , Adulto Jovem
7.
Teach Learn Med ; 29(2): 188-195, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-27997222

RESUMO

THEORY: Empathy is one component of medical student education that may be important to nurture, but there are many potential psychological barriers to empathy, such as student depression, burnout, and low quality of life or wellness behaviors. However, few studies have addressed how positive behaviors such as wellness and spirituality, in combination with these barriers, might affect empathy. HYPOTHESES: We hypothesized a negative relationship between psychological distress and empathy, and a positive relationship between empathy and wellness behaviors. We also hypothesized that openness to others' spirituality would moderate the effects of psychological distress on empathy in medical students. METHOD: This cross-sectional study included 106 medical students in a public medical school in the U.S. Midwest. Mailed questionnaires collected student information on specialty choice and sociodemographics, empathy, spirituality openness, religiosity, wellness, burnout, depression, anxiety, and stress. Hierarchical multiple regression analysis was conducted, with empathy as the dependent variable, psychological distress and all wellness behaviors as predictors, and spirituality openness as a moderator. RESULTS: Specialty choice, burnout, wellness behaviors, spirituality openness, and religiosity were significant independent predictors of empathy. In addition, when added singly, one interaction was significant: Spirituality Openness × Depression. Spirituality openness was related to empathy only in nondepressed students. Empathy of students with higher levels of depression was generally lower and not affected by spirituality openness. CONCLUSIONS: Nondepressed students who reported lower openness to spirituality might benefit most from empathy training, because these students reported the lowest empathy. Highly depressed or disengaged students may require interventions before empathy can be addressed. In addition, burnout was related to lower levels of empathy and wellness was related to higher levels. These provide potential points of intervention for medical schools developing tools to increase medical trainees' empathy levels.


Assuntos
Empatia , Espiritualidade , Estudantes de Medicina/psicologia , Adulto , Estudos Transversais , Feminino , Humanos , Masculino , Inquéritos e Questionários , Adulto Jovem
8.
J Chromatogr A ; 1395: 57-64, 2015 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-25890437

RESUMO

Column selectivity in reversed-phase chromatography (RPC) can be described in terms of the hydrophobic-subtraction model, which recognizes five solute-column interactions that together determine solute retention and column selectivity: hydrophobic, steric, hydrogen bonding of an acceptor solute (i.e., a hydrogen-bond base) by a stationary-phase donor group (i.e., a silanol), hydrogen bonding of a donor solute (e.g., a carboxylic acid) by a stationary-phase acceptor group, and ionic. Of these five interactions, hydrogen bonding between donor solutes (acids) and stationary-phase acceptor groups is the least well understood; the present study aims at resolving this uncertainty, so far as possible. Previous work suggests that there are three distinct stationary-phase sites for hydrogen-bond interaction with carboxylic acids, which we will refer to as column basicity I, II, and III. All RPC columns exhibit a selective retention of carboxylic acids (column basicity I) in varying degree. This now appears to involve an interaction of the solute with a pair of vicinal silanols in the stationary phase. For some type-A columns, an additional basic site (column basicity II) is similar to that for column basicity I in primarily affecting the retention of carboxylic acids. The latter site appears to be associated with metal contamination of the silica. Finally, for embedded-polar-group (EPG) columns, the polar group can serve as a proton acceptor (column basicity III) for acids, phenols, and other donor solutes.


Assuntos
Cromatografia de Fase Reversa/métodos , Cromatografia de Fase Reversa/normas , Ácidos Carboxílicos/química , Ligação de Hidrogênio , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Metais/química , Dióxido de Silício/química
9.
Adv Health Sci Educ Theory Pract ; 20(5): 1179-94, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25737275

RESUMO

The use of students' "consumer feedback" to assess faculty behavior and improve the process of medical education is a significant challenge. We used quantitative Rasch measurement to analyze pre-categorized student comments listed by 385 graduating medical students. We found that students differed little with respect to the number of comments they provided and that their comments indeed form a probabilistic Rasch hierarchy. However, different hierarchies were found across medical departments and faculty. An analysis of these interactions provides valuable, detailed, and quantitative information that can augment qualitative research approaches. In addition, we suggest how the Rasch scaling of student comments can assist researchers in the design and implementation of new faculty evaluation instruments. Finally, the interactions between student and department identified a subset of behaviors that appear to guide and possibly elicit students' comments.


Assuntos
Educação Médica/normas , Docentes de Medicina/normas , Feedback Formativo , Profissionalismo/normas , Estudantes de Medicina/psicologia , Comportamento do Consumidor , Humanos
10.
Acad Med ; 89(7): 1032-7, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24979173

RESUMO

PURPOSE: Unprofessional behavior by faculty can result in poor patient care, poor role modeling, and mistreatment of trainees. To improve faculty or institutional behavior, unprofessional faculty must be given direct feedback. The authors sought to determine whether annually surveying medical students for their nominations of most and least professional faculty, coupled with direct feedback to unprofessional faculty from the dean, improved faculty's professional behavior. METHOD: From 2007 to 2012, senior medical students at Southern Illinois University School of Medicine completed an anonymous survey naming the "most professional" and "least professional" faculty in each department. Students described unprofessional behaviors, and their descriptions were qualitatively analyzed. The most unprofessional faculty met with the dean to discuss their behavior. The authors examined differences between faculty named most professional in their department versus those named least professional and whether behavior as measured by student nominations changed following feedback. RESULTS: The response rate overall for six graduating classes was 92.5% (385/416). Faculty named most professional were highly associated with receiving teaching and humanism awards. Faculty named most unprofessional were shown to either leave the institution or improve their behavior after receiving feedback. CONCLUSIONS: Attitudes and behaviors of teachers create the culture of their institution, and unprofessional behavior by these educators can have a profound, negative effect. Direct involvement by the dean may be an effective tool to improve the learning environment of a single institution, but universal application of such a program is needed if the profession as a whole is to improve its culture.


Assuntos
Docentes de Medicina , Retroalimentação , Competência Profissional , Feminino , Humanos , Masculino , Faculdades de Medicina , Estudantes de Medicina , Inquéritos e Questionários
11.
Work ; 49(3): 363-72, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24858516

RESUMO

BACKGROUND: Green building standards are significantly impacting modern construction practices. The resulting structures are more energy efficient, but their impact on occupant health has not been widely studied. OBJECTIVE: To investigate a range of indoor environment and ergonomic issues in green buildings. METHODS: Retrospective post-occupancy evaluation survey of 319 occupants in two Leadership in Energy and Environmental Design (LEED) certified buildings and one conventional building on a Canadian University campus. RESULTS: Results show that working in the LEED buildings was a generally positive experience for their health, performance, and satisfaction. However, the LEED buildings did not always receive the highest ratings for environmental conditions or for health and productivity. Respondents indicated a range of concerns with thermal conditions, office lighting, noise and their overall workstation designs and these were not always better in the green buildings. CONCLUSIONS: These results highlight the need for better integration of ergonomic design into green buildings and into the LEED rating system, and these implications are discussed.


Assuntos
Conservação dos Recursos Naturais , Ergonomia , Arquitetura de Instituições de Saúde , Universidades , Alberta , Humanos , Estudos Retrospectivos
12.
Med Teach ; 36(7): 621-5, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24787525

RESUMO

BACKGROUND: Unprofessional behavior has well documented negative effects both on the clinical care environment and on the learning environment. If unprofessional behavior varies by department or specialty, this has implications both for faculty development and for undergraduate and graduate level training. AIMS: We sought to learn which unprofessional behaviors were endemic in our school, and which were unique to particular departments. METHODS: Students graduating from medical school between 2007 and 2012 were asked to complete a questionnaire naming the most professional and least professional faculty members they encountered in during school. For the least professional faculty members, they were also asked to provide information about the unprofessional behavior. RESULTS: Students noted several types of unprofessional behavior regardless of the department faculty were in; however, there were some behaviors only noted in individual departments. The unprofessional behavior profiles for Surgery and Obstetrics/Gynecology were markedly similar, and were substantially different from all other specialties. CONCLUSION: Undergraduate, graduate, and faculty education focused on unprofessional behavior that may occur in various learning environments may provide a feasible, practical, and an effective approach to creating a culture of professional behavior throughout the organization.


Assuntos
Docentes de Medicina/normas , Competência Profissional/normas , Estudantes de Medicina/psicologia , Atitude do Pessoal de Saúde , Humanos , Pesquisa Qualitativa , Faculdades de Medicina , Inquéritos e Questionários
13.
Acad Med ; 88(5): 593-602, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23478636

RESUMO

The Medical College Admission Test (MCAT) is a standardized examination that assesses fundamental knowledge of scientific concepts, critical reasoning ability, and written communication skills. Medical school admission officers use MCAT scores, along with other measures of academic preparation and personal attributes, to select the applicants they consider the most likely to succeed in medical school. In 2008-2011, the committee charged with conducting a comprehensive review of the MCAT exam examined four issues: (1) whether racial and ethnic groups differ in mean MCAT scores, (2) whether any score differences are due to test bias, (3) how group differences may be explained, and (4) whether the MCAT exam is a barrier to medical school admission for black or Latino applicants. This analysis showed that black and Latino examinees' mean MCAT scores are lower than white examinees', mirroring differences on other standardized admission tests and in the average undergraduate grades of medical school applicants. However, there was no evidence that the MCAT exam is biased against black and Latino applicants as determined by their subsequent performance on selected medical school performance indicators. Among other factors which could contribute to mean differences in MCAT performance, whites, blacks, and Latinos interested in medicine differ with respect to parents' education and income. Admission data indicate that admission committees accept majority and minority applicants at similar rates, which suggests that medical students are selected on the basis of a combination of attributes and competencies rather than on MCAT scores alone.


Assuntos
Negro ou Afro-Americano , Teste de Admissão Acadêmica , Hispânico ou Latino , Grupos Minoritários , Faculdades de Medicina , População Branca , Logro , Negro ou Afro-Americano/estatística & dados numéricos , Viés , Teste de Admissão Acadêmica/estatística & dados numéricos , Diversidade Cultural , Educação de Graduação em Medicina/estatística & dados numéricos , Hispânico ou Latino/estatística & dados numéricos , Humanos , Modelos Logísticos , Grupos Minoritários/estatística & dados numéricos , Critérios de Admissão Escolar , Faculdades de Medicina/estatística & dados numéricos , Fatores Socioeconômicos , Estados Unidos , População Branca/estatística & dados numéricos
14.
Ergonomics ; 56(3): 492-506, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-22934835

RESUMO

A retrospective post-occupancy evaluation survey of 44 occupants in two Leadership in Energy and Environmental Design (LEED) Platinum buildings on a US college campus is reported. The Internet survey covered a range of indoor environment and ergonomics issues. Results show that working in these buildings were a generally positive experience for their health, performance and satisfaction. However, in one building there were persistent issues of variability in air temperature, air freshness, air quality and noise that affected the perceived health and performance of the occupants. Although the buildings were energy-efficient and sustainable structures, ergonomics design issues were identified. Implications for the role of ergonomics in green buildings and in the US LEED rating system are discussed. PRACTITIONER SUMMARY: This survey identified a number of ergonomics design issues present in the LEED Platinum energy-efficient and sustainable buildings that were studied. These results highlight the importance of integrating ergonomics design into green buildings as a component in the US LEED rating system.


Assuntos
Ergonomia , Arquitetura de Instituições de Saúde , Universidades , Poluição do Ar em Ambientes Fechados/efeitos adversos , Astenopia/etiologia , Computadores , Conservação de Recursos Energéticos , Fadiga/etiologia , Feminino , Cefaleia/etiologia , Humanos , Decoração de Interiores e Mobiliário , Iluminação/efeitos adversos , Masculino , Dor Musculoesquelética/etiologia , Ruído Ocupacional/efeitos adversos , Estudos Retrospectivos , Temperatura , Trabalho
17.
Philos Trans R Soc Lond B Biol Sci ; 366(1582): 3210-24, 2011 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-22006963

RESUMO

We present results from the OP3 campaign in Sabah during 2008 that allow us to study the impact of local emission changes over Borneo on atmospheric composition at the regional and wider scale. OP3 constituent data provide an important constraint on model performance. Treatment of boundary layer processes is highlighted as an important area of model uncertainty. Model studies of land-use change confirm earlier work, indicating that further changes to intensive oil palm agriculture in South East Asia, and the tropics in general, could have important impacts on air quality, with the biggest factor being the concomitant changes in NO(x) emissions. With the model scenarios used here, local increases in ozone of around 50 per cent could occur. We also report measurements of short-lived brominated compounds around Sabah suggesting that oceanic (and, especially, coastal) emission sources dominate locally. The concentration of bromine in short-lived halocarbons measured at the surface during OP3 amounted to about 7 ppt, setting an upper limit on the amount of these species that can reach the lower stratosphere.


Assuntos
Poluição do Ar/análise , Arecaceae/química , Atmosfera/química , Árvores/química , Agricultura , Arecaceae/fisiologia , Atmosfera/análise , Bornéu , Bromo/química , Butadienos/química , Carbanilidas/análise , Carbanilidas/química , Simulação por Computador , Formaldeído/química , Hemiterpenos/química , Malásia , Óxidos de Nitrogênio/química , Oxirredução , Ozônio/química , Pentanos/química , Árvores/fisiologia , Clima Tropical , Compostos Orgânicos Voláteis/química
18.
Acad Med ; 85(4): 588-93, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20354372

RESUMO

PURPOSE: Research is said to show that empathy declines during medical school and residency training. These studies and their results were examined to determine the extent of the decline and the plausibility of any alternative explanations. METHOD: Eleven studies published from 2000 to 2008 which reported empathy at various stages of physician training were reexamined. Their results were transformed back to the original units of the rating scales to make results more interpretable by reporting them in the metric of the original anchors. Next, the relationship between empathy ratings and response rates were examined to see whether response bias was a plausible threat to the validity of the empathy decline conclusion. RESULTS: The changes in mean empathy ranged across the 11 studies from a 0.1-point increase in empathy to a 0.5-point decrease, with an average of a 0.2-point decline for the 11 studies (ratings were on 5-point, 7-point, and 9-point scales). Mean ratings were similar in medical school and residency. Response rates were low and-where reported-declined on average about 26 percentage points. CONCLUSIONS: Reexamination revealed that the evidence does not warrant the strong, disturbing conclusion that empathy declines during medical education. Results show a very weak decline in mean ratings, and even the weak decline is questionable because of the low and varying response rates. Moreover, the empathy instruments are self-reports, and it isn't clear what they measure-or whether what they measure is indicative of patients' perceptions and the effectiveness of patient care.


Assuntos
Pesquisa Biomédica/métodos , Competência Clínica/normas , Atenção à Saúde/normas , Educação Médica/métodos , Empatia , Médicos/psicologia , Humanos , Publicações Periódicas como Assunto , Estudos Retrospectivos , Estados Unidos
19.
Proc Natl Acad Sci U S A ; 106(44): 18447-51, 2009 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-19841269

RESUMO

More than half the world's rainforest has been lost to agriculture since the Industrial Revolution. Among the most widespread tropical crops is oil palm (Elaeis guineensis): global production now exceeds 35 million tonnes per year. In Malaysia, for example, 13% of land area is now oil palm plantation, compared with 1% in 1974. There are enormous pressures to increase palm oil production for food, domestic products, and, especially, biofuels. Greater use of palm oil for biofuel production is predicated on the assumption that palm oil is an "environmentally friendly" fuel feedstock. Here we show, using measurements and models, that oil palm plantations in Malaysia directly emit more oxides of nitrogen and volatile organic compounds than rainforest. These compounds lead to the production of ground-level ozone (O(3)), an air pollutant that damages human health, plants, and materials, reduces crop productivity, and has effects on the Earth's climate. Our measurements show that, at present, O(3) concentrations do not differ significantly over rainforest and adjacent oil palm plantation landscapes. However, our model calculations predict that if concentrations of oxides of nitrogen in Borneo are allowed to reach those currently seen over rural North America and Europe, ground-level O(3) concentrations will reach 100 parts per billion (10(9)) volume (ppbv) and exceed levels known to be harmful to human health. Our study provides an early warning of the urgent need to develop policies that manage nitrogen emissions if the detrimental effects of palm oil production on air quality and climate are to be avoided.


Assuntos
Agricultura , Poluição do Ar/análise , Arecaceae/fisiologia , Nitrogênio/análise , Ozônio/análise , Óleos de Plantas/análise , Clima Tropical , Aeronaves , Butadienos/análise , Geografia , Hemiterpenos/análise , Monoterpenos/análise , Óxido Nítrico/análise , Dióxido de Nitrogênio/análise , Óleo de Palmeira , Pentanos/análise , Ácido Peracético/análogos & derivados , Ácido Peracético/análise , Fatores de Tempo
20.
Int J Obes (Lond) ; 33(6): 693-701, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19350040

RESUMO

OBJECTIVE: Relapsing to overeating is a stubborn problem in obesity treatment. We tested the hypothesis that context cues surrounding palatable food (PF) intake have the power to disrupt caloric regulation even of less PF. Context cues are non-food cues that are in the environment where PF is habitually eaten. DESIGN: Rats were conditioned to associate intake of Oreo cookies as the PF to cages with distinct context cues that differed from cues in cages where they were only given chow. PF naturally stimulated greater caloric intake. The rats were then tested in the PF cage with only chow available to determine whether the PF-paired cues, alone, could elicit overeating of plain chow. SUBJECTS: Non-food-deprived female Sprague-Dawley rats. MEASUREMENTS: Intake of plain chow under PF-paired cues vs chow-paired cues was compared. This was also measured in tests that included a morsel of PF as a priming stimulus. We also controlled for any effect of binge-prone vs binge-resistant status to predict cued-overeating. RESULTS: Rats consumed significantly more chow when exposed to context cues paired earlier with PF than with chow (P<0.01). This effect occurred using various cues (for example, different types of bedding or wallpaper). The effect was strengthened by priming with a morsel of PF (P<0.001) and was unaffected by baseline differences in propensity to binge on PF. CONCLUSION: Context-cues associated with PF intake can drive overeating even of a less PF and abolish the ability of rats to compensate for the calories of a PF primer. Just as drug-associated context cues can reinstate drug-addiction relapse, PF-paired cues may trigger overeating relapses linked to weight regain and obesity. This model should help identify the reflex-like biology that sabotages attempts to adhere to healthy reduced calorie regimens and call greater attention to the cue-factor in the treatment of binge eating and obesity.


Assuntos
Condicionamento Psicológico , Ingestão de Alimentos/fisiologia , Comportamento Alimentar/fisiologia , Preferências Alimentares/fisiologia , Redução de Peso/fisiologia , Animais , Bulimia/psicologia , Sinais (Psicologia) , Comportamento Alimentar/psicologia , Feminino , Preferências Alimentares/psicologia , Hiperfagia/psicologia , Ratos , Ratos Sprague-Dawley
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