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2.
Sci Total Environ ; 639: 815-825, 2018 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-29803052

RESUMEN

A facility-wide estrogen budget model was developed to assess the excretion of natural estrogens by swine in a commercial swine farrowing concentrated animal feeding operations (CAFO) in North Carolina, using an object-oriented Bayesian network (OOBN) approach. The OOBN model is the combination of twelve objects of Bayesian network models, which characterize the estrogen budget flows based on the sow reproductive cycle (i.e., pre-estrus, estrus, and lactation) for the three natural estrogen types [estrone (E1), 17ß-estradiol (E2), and estriol (E3)] within each barn. This OOBN model provides a mechanism to quantify the levels of the natural estrogens and their probabilistic distributions with regard to estrogen type, waste sources such as urine, feces, and recycling lagoon slurry, and animal reproductive status. Moreover, the OOBN model allows us to assess the overall contribution of natural estrogen compounds from each operational unit of the CAFO, while accounting for the uncertainties. Results from the OOBN model indicate a rank order of lactating sows > gestating sows > breeding sows in terms of contribution of estrogen loads to the total natural estrogen budget. As to estrogen type, E1 was found as the major estrogen metabolite with the summed concentrations of urine, feces, and flushing slurry wastes exceeding 3000 ng/l > 90% of the time. As to waste sources, the flushing slurry waste was found to be a major contributor of the estrogen budget compared with urine and feces wastes from barn animals.


Asunto(s)
Teorema de Bayes , Estrógenos/metabolismo , Estiércol/análisis , Eliminación de Residuos Líquidos/métodos , Contaminantes Químicos del Agua/metabolismo , Animales , Estradiol , Estrógenos/análisis , Estrona , Femenino , Lactancia , North Carolina , Porcinos , Contaminantes Químicos del Agua/análisis
3.
Science ; 354(6309)2016 10 14.
Artículo en Inglés | MEDLINE | ID: mdl-27738143

RESUMEN

The biodiversity-productivity relationship (BPR) is foundational to our understanding of the global extinction crisis and its impacts on ecosystem functioning. Understanding BPR is critical for the accurate valuation and effective conservation of biodiversity. Using ground-sourced data from 777,126 permanent plots, spanning 44 countries and most terrestrial biomes, we reveal a globally consistent positive concave-down BPR, showing that continued biodiversity loss would result in an accelerating decline in forest productivity worldwide. The value of biodiversity in maintaining commercial forest productivity alone-US$166 billion to 490 billion per year according to our estimation-is more than twice what it would cost to implement effective global conservation. This highlights the need for a worldwide reassessment of biodiversity values, forest management strategies, and conservation priorities.


Asunto(s)
Biodiversidad , Conservación de los Recursos Naturales , Bosques , Árboles/fisiología , Cambio Climático , Extinción Biológica
4.
Sci Total Environ ; 532: 571-80, 2015 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-26102057

RESUMEN

Animal feeding operations (AFOs) have been implicated as potentially major sources of estrogenic contaminants into the aquatic environment due to the relatively minimal treatment of waste and potential mobilization and transport of waste components from spray fields. In this study a Bayesian network (BN) model was developed to inform management decisions and better predict the transport and fate of natural steroidal estrogens from these sites. The developed BN model integrates processes of surface runoff and sediment loss with the modified universal soil loss equation (MUSLE) and the soil conservation service curve number (SCS-CN) runoff model. What-if scenario simulations of lagoon slurry wastes to the spray fields were conducted for the most abundant natural estrogen estrone (E1) observed in the system. It was found that E1 attenuated significantly after 2 months following waste slurry application in both spring and summer seasons, with the overall attenuation rate predicted to be higher in the summer compared to the spring. Using simulations of rainfall events in conjunction with waste slurry application rates, it was predicted that the magnitude of E1 runoff loss is significantly higher in the spring as compared to the summer months, primarily due to spray field crop management plans. Our what-if scenario analyses suggest that planting Bermuda grass in the spray fields is likely to reduce runoff losses of natural estrogens near the water bodies and ecosystems, as compared to planting of soybeans.


Asunto(s)
Monitoreo del Ambiente/métodos , Estrógenos/análisis , Lluvia , Movimientos del Agua , Contaminantes Químicos del Agua/análisis , Contaminación Química del Agua/estadística & datos numéricos , Agricultura/métodos , Alimentación Animal , Animales , Teorema de Bayes , Sedimentos Geológicos , Estiércol , Modelos Químicos , Suelo/química , Porcinos
5.
Environ Sci Technol ; 48(19): 11600-9, 2014 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-25148584

RESUMEN

The inflow, transformation, and attenuation of natural steroid hormones and phytoestrogens and estrogenic activity were assessed across the lagoon/sprayfield system of a prototypical commercial swine sow operation. Free and conjugated steroid hormones (estrogens, androgens, and progesterone) were detected in urine and feces of sows across reproductive stages, with progesterone being the most abundant steroid hormone. Excreta also contained phytoestrogens indicative of a soy-based diet, particularly, daidzein, genistein, and equol. During storage in barn pits and the anaerobic lagoon, conjugated hormones dissipated, and androgens and progesterone were attenuated. Estrone and equol persisted along the waste disposal route. Following application of lagoon slurry to agricultural soils, all analytes exhibited attenuation within 2 days. However, analytes including estrone, androstenedione, progesterone, and equol remained detectable in soil at 2 months postapplication. Estrogenic activity in the yeast estrogen screen and T47D-KBluc in vitro bioassays generally tracked well with analyte concentrations. Estrone was found to be the greatest contributor to estrogenic activity across all sample types. This investigation encompasses the most comprehensive suite of natural hormone and phytoestrogen analytes examined to date across a livestock lagoon/sprayfield and provides global insight into the fate of these analytes in this widely used waste management system.


Asunto(s)
Agricultura/métodos , Monitoreo del Ambiente/métodos , Estrógenos/química , Hormonas/química , Fitoestrógenos/química , Andrógenos/química , Androstenodiona/química , Animales , Dieta/veterinaria , Equol/química , Estrona/química , Heces/química , Genisteína/química , Isoflavonas/química , Progesterona/química , Esteroides/química , Porcinos , Orina/química
6.
Integr Environ Assess Manag ; 10(4): 511-21, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24798317

RESUMEN

Commercial swine waste lagoons are regarded as a major reservoir of natural estrogens, which have the potential to produce adverse physiological effects on exposed aquatic organisms and wildlife. However, there remains limited understanding of the complex mechanisms of physical, chemical, and biological processes that govern the fate and transport of natural estrogens within an anaerobic swine lagoon. To improve lagoon management and ultimately help control the offsite transport of these compounds from swine operations, a probabilistic Bayesian network model was developed to assess natural estrogen fate and budget and then compared against data collected from a commercial swine field site. In general, the model was able to describe the estrogen fate and budget in both the slurry and sludge stores within the swine lagoon. Sensitivity analysis within the model demonstrated that the estrogen input loading from the associated barn facility was the most important factor in controlling estrogen concentrations within the lagoon slurry storage, whereas the settling rate was the most significant factor in the lagoon sludge storage. The degradation reactions were shown to be minor in both stores based on prediction of average total estrogen concentrations. Management scenario evaluations demonstrated that the best possible management options to reduce estrogen levels in the lagoon are either to adjust the estrogen input loading from swine barn facilities or to effectively enhance estrogen bonding with suspended solids through the use of organic polymers or inorganic coagulants.


Asunto(s)
Estrógenos/química , Modelos Teóricos , Aguas del Alcantarillado/química , Porcinos , Eliminación de Residuos Líquidos , Contaminantes Químicos del Agua/química , Animales , Teorema de Bayes
7.
Environ Sci Technol ; 47(23): 13781-90, 2013 Dec 03.
Artículo en Inglés | MEDLINE | ID: mdl-24144340

RESUMEN

In this study, the distribution of steroid hormones, phytoestrogens, and estrogenic activity was thoroughly characterized within the anaerobic waste lagoon of a typical commercial swine sow operation. Three independent rounds of sampling were conducted in June 2009, April 2010, and February 2011. Thirty-seven analytes in lagoon slurry and sludge were assessed using LC/MS-MS, and yeast estrogen screen was used to determine estrogenic activity. Of the hormone analytes, steroidal estrogens were more abundant than androgens or progesterone, with estrone being the predominant estrogen species. Conjugated hormones were detected only at low levels. The isoflavone metabolite equol was by far the predominant phytoestrogen species, with daidzein, genistein, formononetin, and coumestrol present at lower levels. Phytoestrogens were often more abundant than steroidal estrogens, but contributed minimally toward total estrogenic activity. Analytes were significantly elevated in the solid phases of the lagoon; although low observed log KOC values suggest enhanced solubility in the aqueous phase, perhaps due to dissolved or colloidal organic carbon. The association with the solid phase, as well as recalcitrance of analytes to anaerobic degradation, results in a markedly elevated load of analytes and estrogenic activity within lagoon sludge. Overall, findings emphasize the importance of adsorption and transformation processes in governing the fate of these compounds in lagoon waste, which is ultimately used for broadcast application as a fertilizer.


Asunto(s)
Estrógenos/análisis , Fitoestrógenos/análisis , Aguas Residuales/química , Anaerobiosis , Animales , Cromatografía Liquida , Espectrometría de Masas , Aguas del Alcantarillado/química , Porcinos , Contaminantes Químicos del Agua/análisis
8.
Taehan Kanho Hakhoe Chi ; 36(6): 968-75, 2006 Oct.
Artículo en Coreano | MEDLINE | ID: mdl-17090996

RESUMEN

PURPOSE: The purpose of this study was to evaluate the effects of preoperative pain control education on the pain control barrier, postoperative pain and pain control satisfaction in gynecological patients. METHOD: The study was a quasi-experimental research design. There were 58 subjects who were admitted for gynecological surgery to D University Hospital in B city. Pain control education was provided individually to the experimental group one day before their operation day for 20 minutes with the 'Pain Control Guide Book' in the patient's admission room. The education book was made by researchers based on pain management references and patient interviews. For assessing the pain control barrier, a simplified version of Barriers Questionnaire was used, postoperative pain was assessed on a numeric scale(0-10) and satisfaction of pain control was assessed by one question. RESULTS: The pain control barrier(F=15.828, p<.001) and the post pain score of the experimental group was lower than that of the control group. In addition, pain control satisfaction of the experimental group(t=3.612, p<.001) was higher than the control group's. CONCLUSION: With the above results, preoperative pain control education could be an effective nursing intervention for pain control of surgical patients.


Asunto(s)
Enfermedades de los Genitales Femeninos/enfermería , Dolor Postoperatorio/prevención & control , Dolor/prevención & control , Educación del Paciente como Asunto , Adulto , Anciano , Femenino , Enfermedades de los Genitales Femeninos/patología , Humanos , Persona de Mediana Edad , Dolor/enfermería , Dolor Postoperatorio/enfermería , Satisfacción del Paciente , Cuidados Preoperatorios/enfermería
9.
Taehan Kanho Hakhoe Chi ; 36(7): 1242-52, 2006 Dec.
Artículo en Coreano | MEDLINE | ID: mdl-17211127

RESUMEN

PURPOSE: The purpose of this study was to identify the attitude of nurses toward transsexuals. METHOD: The Q-methodology which provides a method of analyzing the subjectivity of each item was used. Twenty-nine nurses classified the 50 selected Q-statements into a normal distribution using a 9 point scale. The collected data was analyzed using the Quanl PC program. RESULT: Four types of attitudes toward transsexuals were identified. The first type (humanitarian acceptance) showed an attitude of respecting transsexuals as human beings and understanding and accepting their desires and difficulties. The second type (superficial understanding) understood the psychological conflicts and suffering of transsexuals but could not accept them as members of families or society. The third type (insufficient understanding) did not feel a sense of rejection toward transsexuals but showed a lack of understanding of their desires and difficulties. The fourth type (rejection) failed to understand the desires and difficulties of transsexuals and showed a sense of rejection toward them, in addition to regarding them as sexually immoral people. CONCLUSION: The results of the study indicate that different approaches of educational programs based on the four types of attitudes toward transsexuals are recommended.


Asunto(s)
Actitud del Personal de Salud , Personal de Enfermería/psicología , Transexualidad , Adulto , Demografía , Femenino , Humanos , Modelos Educacionales , Q-Sort , Encuestas y Cuestionarios
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