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1.
Plant Methods ; 17(1): 1, 2021 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-33407638

RESUMEN

BACKGROUND: Forest dieback driven by rapid climate warming threatens ecosystems worldwide. The health of forested ecosystems depends on how tree species respond to warming during all life history stages. While it is known that seed development is temperature-sensitive, little is known about possible effects of climate warming on seed development and subsequent seedling performance. Exposure of seeds to high air temperatures may influence subsequent seedling performance negatively, though conversely, warming during seed development may aid acclimation of seedlings to subsequent thermal stress. Technical challenges associated with in-situ warming of developing tree seeds limit understanding of how tree species may respond to seed development in a warmer climate. RESULTS: We developed and validated a simple method for passively warming seeds as they develop in tree canopies to enable controlled study of climate warming on seedling performance. We quantified thermal effects of the cone-warming method across individual pine trees and stands by measuring the air temperature surrounding seed cones using thermal loggers and the temperature of seed cone tissue using thermocouples. We then investigated seedling phenotypes in relation to the warming method through a common garden study. We assessed seedling morphology, physiology, and mycorrhizal nodulation in response to experimental cone-warming in 20 seed-source-tree canopies on the San Francisco Peaks in northern Arizona, USA. The warming method increased air temperature surrounding developing seed cones by 2.1 °C, a plausible increase in mean air temperature by 2050 under current climate projections. Notable effect sizes of cone-warming were detected for seedling root length, shoot length, and diameter at root collar using Cohen's Local f2. Root length was affected most by cone-warming, but effect sizes of cone-warming on root length and diameter at root collar became negligible after the first year of growth. Cone-warming had small but significant effects on mycorrhizal fungal richness and seedling multispectral near-infrared indices indicative of plant health. CONCLUSIONS: The method was shown to reliably elevate the temperature surrounding seed cones and thereby facilitate experimental in-situ climate warming research on forest trees. The method was furthermore shown to influence plant traits that may affect seedling performance under climate warming.

2.
Br J Cancer ; 104(12): 1836-9, 2011 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-21610709

RESUMEN

BACKGROUND: Poor cancer survival rates in the United Kingdom are often blamed on delayed medical care. A local audit of endometrial cancer revealed a variety of preventable delays. We surveyed practice in the South West of England to see if this was an isolated or widespread problem. METHODS: All 15 hospitals in the South West of England collected information prospectively from all women with endometrial cancer over 3 months in the spring of 2009. RESULTS: There were delays in all stages of the uterine cancer pathway. Excluding extraneous cases, 52% of women waited more than a month and 12% waited more than 6 months to see their GP from the onset of symptoms. Almost half the cases said they were unaware that abnormal bleeding was a symptom of cancer. Only a quarter of women had treatment within 31 days from the outpatient visit to first definitive treatment and 18% waited more than the target of 62 days for their treatment. CONCLUSIONS: Significant treatment delays occur because women do not report bleeding. If this is replicated throughout Britain, approximately 1000 women per year will delay presentation for at least 3 months and 600 will wait for more than 6 months.


Asunto(s)
Diagnóstico Tardío , Neoplasias Endometriales/terapia , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias Endometriales/diagnóstico , Inglaterra , Femenino , Médicos Generales , Humanos , Persona de Mediana Edad , Estadificación de Neoplasias , Derivación y Consulta , Factores de Tiempo
3.
Phys Rev A ; 54(5): 3923-3938, 1996 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-9913940
4.
J Am Coll Health ; 39(6): 263-8, 1991 May.
Artículo en Inglés | MEDLINE | ID: mdl-2033170

RESUMEN

This study analyzed the frequency and type of questions about sex and sexuality that were anonymously submitted by college undergraduates enrolled in personal health education courses at three universities. More than 1,300 queries were submitted by 626 students (249 men and 377 women) from an original pool of 644 possible subjects. Questions asked most often fell into six general categories: sexual arousal/response, general anatomy/physiology, contraception, dating/relationships, pregnancy/fertility, and sexually transmitted diseases. Queries concerning sexual arousal/response accounted for just over 30% of the questions from men and 25% of the questions from women. Women asked nearly twice as many questions about pregnancy and contraception as men did, and men asked far more about general anatomy/physiology and sexually transmitted diseases than women did. Chi-square analysis identified a significant association (p less than .001) between the sex of the questioner and the categories of sexual arousal/response and pregnancy/fertility. Physicians, psychologists, nurses, counselors, and educators should be aware that a considerable degree of sexual uncertainty still exists among college undergraduates. The authors concluded that the anonymous-submission technique was an effective means of enhancing the learning process and meeting student needs in sexuality education.


Asunto(s)
Interpretación Estadística de Datos , Educación Sexual , Conducta Sexual/psicología , Estudiantes/psicología , Adolescente , Femenino , Humanos , Masculino , Conducta Sexual/estadística & datos numéricos , Encuestas y Cuestionarios , Universidades
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