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1.
Sci Total Environ ; 817: 152723, 2022 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-34979231

RESUMEN

Green stormwater infrastructure (GSI), which includes features like rain gardens, constructed wetlands, or urban tree canopy, is now widely recognized as a means to reduce urban runoff impacts and meet municipal water quality permit requirements. Many co-benefits of GSI are related to increased vegetative cover, which can be measured with satellite imagery via spectral indices such as the Normalized Difference Vegetation Index (NDVI). In urban landscapes, there remain critical gaps in understanding how urban greenness and GSI influence hydrology. Here, we quantify these relationships to assess the feasibility of tracking the effectiveness of urban greening for improving downstream hydrologic conditions. We combined hydrologic data from the United States Geological Survey (USGS) gauges with an NDVI time series (1985-2019) derived from Landsat satellite imagery, and synthesis of GSI implementation data from a set of 372 urbanized watersheds across the United States. We used a multivariate panel modeling approach to account for spatial and time varying factors (rainfall, temperature, urban cover expansion) in an effort to isolate the relationships of interest. After accounting for expansion of urban boundaries, only 32 watersheds (9%) showed significant greenness trends, a majority of which were reductions. Urban greenness had significant influences on downstream flow responses, so that on average, a 10% greenness increase showed a corresponding reduction of total flow (-3.8%), flow variance (-7.7%), peak flows (-4.7%), high flows (-7.6%), flashiness (-2.2%), and high flow frequency (-1.5%); and a corresponding increase in baseflow (4.3%). For a subset of these watersheds for which GSI data were available (n = 48), the level of GSI implementation showed a significant, but weak influence on urban greenness with a 20% increase in BMP density corresponding to a greenness increase of 0.9%. The study results may support valuation and verification of GSI co-benefits in urbanized landscapes at the watershed scale.


Asunto(s)
Hidrología , Tecnología de Sensores Remotos , Lluvia , Árboles , Humedales
2.
Br Paramed J ; 6(1): 38-45, 2021 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-34335099

RESUMEN

BACKGROUND: Spinal cord injury (SCI) is a rare event, with high numbers of patients unnecessarily immobilised with no potential benefit based on limited evidence from the 1950s and 1960s. Contemporary opinion now challenges the notion that traditional immobilisation prevents movement and protects the spine. Current literature suggests that these methods which include semi-rigid collars can potentially cause more movement of the spine and harm the patient. The purpose of this study was to explore the views and perspectives of pre-hospital care providers on immobilising patients without the use of a semi-rigid collar. METHODS: Focus groups were used to allow individuals to discuss and comment on a new method of immobilisation which omits the semi-rigid collar and to capture the thoughts, feelings and experiences of participants. Thematic analysis of the coded transcriptions was used to identify emerging themes. RESULTS: Three focus groups were conducted with 15 participants in each. Participants were all exposed to patients sustaining trauma within their professional roles. Six intertwined themes emerged from the analysis: communication, conflict, education/training, empowerment, risk and the patient. Woven between these themes are the complex interactions that bring together the inter-professional relationships with other emergency services and hospital staff, the patient, the public and pre-hospital care providers. DISCUSSION: Existing immobilisation practices are being challenged, with clinicians empowered to tailor practice to meet specific patient needs. There is limited empirical evidence to support current immobilisation practices. Contemporary literature suggests current practices may potentially cause harm. New pragmatic immobilisation practices are gradually being adopted by some pre-hospital care providers. CONCLUSION: This study explored the perspectives of pre-hospital care providers on immobilising patients without the use of a semi-rigid collar for potential SCI. The consensus of the participants supports a pragmatic approach to managing potential SCI that provides safe, high-quality patient-centred care.

3.
J Phys Act Health ; 15(11): 834-839, 2018 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-30314418

RESUMEN

BACKGROUND: This study examined the association between residential segregation and obesity for Whites, African Americans, Hispanics, and Asians. This study considered 3 dimensions of residential segregation, isolation, dissimilarity, and concentration. METHODS: By combining individual-level data from the Behavioral Risk Factor Surveillance System and county-level data from the County Health Rankings and Roadmaps, the total sample size was 204,610 respondents (160,213 Whites, 21,865 African Americans, 18,027 Hispanics, and 4505 Asians) from 205 counties in the United States. Two-level logistic regression models were performed. RESULTS: African Americans and Hispanics in counties with high levels of isolation, dissimilarity, and concentration were more likely to be obese; these relationships did not hold true for Whites and Asians. Counties with a higher percentage of populations with the income below the poverty line and a higher percentage of fast food restaurants in the county were associated with a higher likelihood of obesity for all racial/ethnic groups. African Americans and Hispanics with low levels of education and income were more likely to be obese. CONCLUSIONS: Residential segregation had a contextual influence on weight status, and the context of counties influenced racial/ethnic groups differently. Obesity reduction programs should consider the contextual influence on minority populations and target subgroups living in highly segregated areas.


Asunto(s)
Pueblo Asiatico/estadística & datos numéricos , Negro o Afroamericano/estadística & datos numéricos , Peso Corporal , Hispánicos o Latinos/estadística & datos numéricos , Grupos Minoritarios/estadística & datos numéricos , Obesidad/etnología , Características de la Residencia/estadística & datos numéricos , Segregación Social , Población Blanca/estadística & datos numéricos , Adulto , Sistema de Vigilancia de Factor de Riesgo Conductual , Etnicidad , Femenino , Vivienda/estadística & datos numéricos , Humanos , Renta , Masculino , Persona de Mediana Edad , Pobreza/estadística & datos numéricos , Estados Unidos
4.
Learn Mem ; 25(2): 105-108, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-29339562

RESUMEN

Reality-monitoring errors occur when internally generated thoughts are remembered as external occurrences. We hypothesized that sleep-dependent memory consolidation could reduce them by strengthening connections between items and their contexts during an afternoon nap. Participants viewed words and imagined their referents. Pictures of the referents also accompanied half of the words. After a 2-h break filled with sleep (n = 31) or wakefulness (n = 32), participants indicated if they previously viewed a picture of each word. Nap participants made fewer reality-monitoring errors than wake participants by adopting more stringent response criteria, suggesting that sleep reduces reality-monitoring errors primarily by influencing post-retrieval decision processes.


Asunto(s)
Toma de Decisiones , Consolidación de la Memoria , Reconocimiento en Psicología , Sueño , Pensamiento , Adolescente , Adulto , Toma de Decisiones/fisiología , Humanos , Consolidación de la Memoria/fisiología , Reconocimiento Visual de Modelos/fisiología , Polisomnografía , Distribución Aleatoria , Reconocimiento en Psicología/fisiología , Semántica , Sueño/fisiología , Pensamiento/fisiología , Vigilia , Adulto Joven
5.
Waste Manag ; 74: 52-62, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29366796

RESUMEN

Throughout the world, much food produced is wasted. The resource impact of producing wasted food is substantial; however, little is known about the energy and water consumed in managing food waste after it has been disposed. Herein, we characterize food waste within the Food-Energy-Water (FEW) nexus and parse the differential FEW effects of producing uneaten food and managing food loss and waste. We find that various food waste management options, such as waste prevention, landfilling, composting, anaerobic digestion, and incineration, present variable pathways for FEW impacts and opportunities. Furthermore, comprehensive sustainable management of food waste will involve varied mechanisms and actors at multiple levels of governance and at the level of individual consumers. To address the complex food waste problem, we therefore propose a "food-waste-systems" approach to optimize resources within the FEW nexus. Such a framework may be applied to devise strategies that, for instance, minimize the amount of edible food that is wasted, foster efficient use of energy and water in the food production process, and simultaneously reduce pollution externalities and create opportunities from recycled energy and nutrients. Characterization of FEW nexus impacts of wasted food, including descriptions of dynamic feedback behaviors, presents a significant research gap and a priority for future work. Large-scale decision making requires more complete understanding of food waste and its management within the FEW nexus, particularly regarding post-disposal impacts related to water.


Asunto(s)
Alimentos , Administración de Residuos , Incineración , Reciclaje , Agua
6.
Phys Rev E ; 93: 043119, 2016 04.
Artículo en Inglés | MEDLINE | ID: mdl-27176402

RESUMEN

In Taylor's theory, the longitudinal dispersion in turbulent pipe flows approaches, on long time scales, a diffusive behavior with a constant diffusivity K_{L}, which depends empirically on the Reynolds number Re. We show that the dependence on Re can be determined from the turbulent energy spectrum. By using the intimate connection between the friction factor and the longitudinal dispersion in wall-bounded turbulence, we predict different asymptotic scaling laws of K_{L}(Re) depending on the different turbulent cascades in two-dimensional turbulence. We also explore numerically the K_{L}(Re) dependence in turbulent channel flows with smooth and rough walls using a lattice Boltzmann method.

7.
Artículo en Inglés | MEDLINE | ID: mdl-25353477

RESUMEN

A supersaturated fluid flowing over a reactive, rough surface leads to complex precipitation patterns. We study the growth and interaction between discrete precipitates along a reactive wall in a nonlaminar channel flow. We show that the competition between advective transport, diffusion, and mixing strongly influences the downstream precipitates morphology and the typical correlation length between different precipitates.

8.
Am Nat ; 174(1): 13-23, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19422319

RESUMEN

Fire has been the dominant disturbance in boreal America since the Pleistocene, resulting in a spatial mosaic in which the most fire occurs in the continental northwest. Spatial variation in snowshoe hare (Lepus americanus) density reflects the fire mosaic. Because fire initiates secondary forest succession, a fire mosaic creates variation in the abundance of early successional plants that snowshoe hares eat in winter, leading to geographic variation in hare density. We hypothesize that fire is the template for a geographic mosaic of natural selection: where fire is greatest and hares are most abundant, hare browsing has most strongly selected juvenile-phase woody plants for defense. We tested the hypothesis at multiple spatial scales using Alaska birch (Betula neoalaskana) and white birch (Betula papyrifera). We also examined five alternative hypotheses for geographic variation in antibrowsing defense. The fire-hare-defense hypothesis was supported at transcontinental, regional, and local scales; alternative hypotheses were rejected. Our results link transcontinental variation in species interactions to an abiotic environmental driver, fire. Intakes of defense toxins by Alaskan hares exceed those by Wisconsin hares, suggesting that the proposed selection mosaic may coincide with a geographic mosaic of coevolution.


Asunto(s)
Betula/genética , Betula/metabolismo , Ecosistema , Incendios , Liebres/genética , Animales , Evolución Biológica , Liebres/metabolismo , Toxinas Biológicas , Árboles , Triterpenos/metabolismo
9.
Biol Bull ; 209(1): 21-30, 2005 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16110091

RESUMEN

Activated Spisula oocytes proceed through meiotic stages rapidly and in near synchrony, providing an excellent system for analyzing polar body formation. Our previous studies suggested that cortical spreading of the metaphase peripheral aster determines spatial features of the cortical F-actin ring that is generated prior to extrusion of the polar body. We tested this hypothesis by experimentally altering the number and cortical contact patterns of peripheral asters. Such alteration was achieved by (a) lovastatin-induced arrest at metaphase I, with and without hexylene glycol modification, followed by washout; and (b) cytochalasin-D inhibition of extrusion of the first polar body, with washout before extrusion of the second polar body. Both methods induced simultaneous formation of two or more cortically spreading asters, correlated with subsequent formation of double, or even triple, overlapping F-actin rings during anaphase. Regardless of pattern, ring F-actin was deposited near regions of greatest astral microtubule density, indicating that microtubules provided a positive stimulus to which the cortex responded indiscriminately. These results strongly support the proposed causal relationship between peripheral aster spreading and biogenesis of the F-actin ring involved in polar body formation.


Asunto(s)
Bivalvos/fisiología , Oocitos/fisiología , Actinas/efectos de los fármacos , Animales , Bivalvos/citología , Citocalasina D/farmacología , Citoesqueleto/efectos de los fármacos , Citoesqueleto/fisiología , Glicoles/farmacología , Lovastatina/farmacología , Metafase/efectos de los fármacos , Metafase/fisiología , Oocitos/efectos de los fármacos , Oocitos/ultraestructura
10.
J Immunol ; 172(12): 7425-31, 2004 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-15187120

RESUMEN

Dendritic cells (DC) play a critical role in adaptive immunity by presenting Ag, thereby priming naive T cells. Specific DC-binding peptides were identified using a phage display peptide library. DC-peptides were fused to hepatitis C virus nonstructural protein 3 (NS3) while preserving DC targeting selectivity and Ag immunogenicity. The NS3-DC-peptide fusion protein was efficiently presented to CD4+ and CD8+ T cells derived from hepatitis C virus-positive blood cells, inducing their activation and proliferation. This immunogenic fusion protein was significantly more potent than NS3 control fusion protein or NS3 alone. In chimeric NOD-SCID mice transplanted with human cells, DC-targeted NS3 primed naive CD4+ and CD8+ T cells for potent NS3-specific proliferation and cytokine secretion. The capacity of peptides to specifically target immunogenic Ags to DC may establish a novel strategy for vaccine development.


Asunto(s)
Antígenos Virales/inmunología , Células Dendríticas/inmunología , Péptidos/inmunología , Animales , Presentación de Antígeno , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos/inmunología , División Celular/inmunología , Citocinas/metabolismo , Femenino , Humanos , Ratones , Ratones Endogámicos BALB C , Ratones SCID , Biblioteca de Péptidos , Péptidos/síntesis química , Proteínas Recombinantes de Fusión , Proteínas no Estructurales Virales/inmunología
11.
J Shoulder Elbow Surg ; 11(6): 614-7, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-12469089

RESUMEN

The glenoids of 412 scapula specimens were templated with the use of 6 currently available glenoid systems to determine the goodness of fit for the various designs. When a fitting criterion of a mismatch of less than 2 mm between the template and the actual glenoid periphery for 8 radial locations was used, the various designs fit from 0% to 48% of the glenoids. Because glenoid component fixation longevity can depend on the degree of osseous support, these results indicate that glenoid component design and sizing can be improved.


Asunto(s)
Ajuste de Prótesis , Escápula/anatomía & histología , Articulación del Hombro/fisiología , Adulto , Anciano , Anciano de 80 o más Años , Cadáver , Femenino , Humanos , Prótesis Articulares , Masculino , Persona de Mediana Edad , Diseño de Prótesis , Escápula/fisiología , Sensibilidad y Especificidad , Articulación del Hombro/anatomía & histología , Estrés Mecánico
12.
J Pain Symptom Manage ; 23(5): 369-82, 2002 May.
Artículo en Inglés | MEDLINE | ID: mdl-12007755

RESUMEN

The purpose of this study was to describe the difficulties with pain management that patients and family caregivers bring to a nurse's attention during a teaching and coaching intervention. Data were obtained from audiotaped and transcribed interactions between intervention nurses and patients (n = 52) and their family caregivers (n = 33) who were participating in a randomized clinical trial of a nursing intervention called the PRO-SELF Copyright Pain Control Program. Using qualitative content analysis, we found that patients had difficulty in seven areas when they attempted to put a pain management regimen into practice, namely: obtaining the prescribed medication(s), accessing information, tailoring prescribed regimens to meet individual needs, managing side effects, cognitively processing information, managing new or unusual pain, and managing multiple symptoms simultaneously. The findings from this study suggest that the provision of information about cancer pain management to patients and their family caregivers is not sufficient to improve pain control in the home care setting. Patients and their family caregivers require ongoing assistance with problem-solving to optimize their pain management regimen.


Asunto(s)
Servicios de Atención de Salud a Domicilio , Neoplasias/complicaciones , Manejo del Dolor , Dolor/etiología , Cuidados Paliativos/métodos , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad
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