Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 4 de 4
Filtrar
1.
J Fluoresc ; 31(1): 29-38, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33048296

RESUMEN

Firstly, a novel pyrazole-pyrazoline fluorescent probe was developed and synthesized. The probe can be used to determine Fe3+ ions in a series of cations in tetrahydrofuran aqueous solution with high selectivity and high sensitivity. After the addition of iron ions, the fluorescence intensity is significantly reduced, Its structure was characterized by 1H NMR, 13C NMR and HR-ESI-MS. UV absorption spectra and Fluorescence spectroscopy were used to study the selective recognition of probe M on metal ions. The probe M can selectivity and sensitivity to distinguish the target ion from other ions through different fluorescence phenomena. In addition, the binding modes of M with Fe3+ were proved to be 1:1 stoichiometry in the complexes by Job's plot, IR results. The combination of probe M and iron ions is 1:1, and the detection limit is 3.9 × 10-10 M. The binding mode and sensing mechanism of M with Fe3+ was verified by theoretical calculations using Gaussian 09 based on B3LYP/6-31G(d) basis.

2.
Pet Sci ; 15(1): 135-145, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29515626

RESUMEN

The most prominent aspect of multiphase flow is the variation in the physical distribution of the phases in the flow conduit known as the flow pattern. Several different flow patterns can exist under different flow conditions which have significant effects on liquid holdup, pressure gradient and heat transfer. Gas-liquid two-phase flow in an annulus can be found in a variety of practical situations. In high rate oil and gas production, it may be beneficial to flow fluids vertically through the annulus configuration between well tubing and casing. The flow patterns in annuli are different from pipe flow. There are both casing and tubing liquid films in slug flow and annular flow in the annulus. Multiphase heat transfer depends on the hydrodynamic behavior of the flow. There are very limited research results that can be found in the open literature for multiphase heat transfer in wellbore annuli. A mechanistic model of multiphase heat transfer is developed for different flow patterns of upward gas-liquid flow in vertical annuli. The required local flow parameters are predicted by use of the hydraulic model of steady-state multiphase flow in wellbore annuli recently developed by Yin et al. The modified heat-transfer model for single gas or liquid flow is verified by comparison with Manabe's experimental results. For different flow patterns, it is compared with modified unified Zhang et al. model based on representative diameters.

3.
Am J Prev Med ; 53(3): 290-299, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28641912

RESUMEN

INTRODUCTION: This study sought to determine the effect of a 2-year, multicomponent health intervention (Spirited Life) targeting metabolic syndrome and stress simultaneously. DESIGN: An RCT using a three-cohort multiple baseline design was conducted in 2010-2014. SETTING/PARTICIPANTS: Participants were United Methodist clergy in North Carolina, U.S., in 2010, invited based on occupational status. Of invited 1,745 clergy, 1,114 consented, provided baseline data, and were randomly assigned to immediate intervention (n=395), 1-year waitlist (n=283), or 2-year waitlist (n=436) cohorts for a 48-month trial duration. INTERVENTION: The 2-year intervention consisted of personal goal setting and encouragement to engage in monthly health coaching, an online weight loss intervention, a small grant, and three workshops delivering stress management and theological content supporting healthy behaviors. Participants were not blinded to intervention. MAIN OUTCOME MEASURES: Trial outcomes were metabolic syndrome (primary) and self-reported stress and depressive symptoms (secondary). Intervention effects were estimated in 2016 in an intention-to-treat framework using generalized estimating equations with adjustment for baseline level of the outcome and follow-up time points. Log-link Poisson generalized estimating equations with robust SEs was used to estimate prevalence ratios (PRs) for binary outcomes; mean differences were used for continuous/score outcomes. RESULTS: Baseline prevalence of metabolic syndrome was 50.9% and depression was 11.4%. The 12-month intervention effect showed a benefit for metabolic syndrome (PR=0.86, 95% CI=0.79, 0.94, p<0.001). This benefit was sustained at 24 months of intervention (PR=0.88; 95% CI=0.78, 1.00, p=0.04). There was no significant effect on depression or stress scores. CONCLUSIONS: The Spirited Life intervention improved metabolic syndrome prevalence in a population of U.S. Christian clergy and sustained improvements during 24 months of intervention. These findings offer support for long-duration behavior change interventions and population-level interventions that allow participants to set their own health goals. TRIAL REGISTRATION: This study is registered at www.clinicaltrials.gov NCT01564719.


Asunto(s)
Depresión/prevención & control , Conductas Relacionadas con la Salud , Salud Holística , Síndrome Metabólico/prevención & control , Estrés Psicológico/prevención & control , Programas de Reducción de Peso/estadística & datos numéricos , Adulto , Clero/estadística & datos numéricos , Estudios de Cohortes , Depresión/epidemiología , Femenino , Humanos , Masculino , Síndrome Metabólico/epidemiología , Persona de Mediana Edad , North Carolina/epidemiología , Medición de Resultados Informados por el Paciente , Prevalencia , Evaluación de Programas y Proyectos de Salud , Protestantismo , Calidad de Vida , Estrés Psicológico/complicaciones , Factores de Tiempo
4.
Contemp Clin Trials ; 35(2): 138-52, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23685205

RESUMEN

Clergy suffer from high rates of obesity, chronic disease, and depression, and simultaneously underestimate the toll these take on their daily functioning. Health interventions are needed for clergy and may be tailored to their occupational context and theological beliefs. Few studies have sought to improve clergy health. No prior studies have utilized a randomized design. Spirited Life is a randomized, multiple baseline study that offered enrollment to nearly all United Methodist Church clergy in North Carolina in fall 2010. A total of 1114 clergy (response rate = 64%) enrolled. Using a multiple baseline design, we randomized participants to three cohorts. Each cohort began the health intervention in one of three consecutive years. The third cohort served as a randomized waitlist control cohort, allowing comparisons between the first and third cohorts. The two-year Spirited Life intervention consists of: 1) a theological underpinning for health stewardship based on incarnation, grace, and response and delivered during workshops; 2) the stress management program Williams LifeSkills; 3) Naturally Slim, an online weight loss program; 4) phone contact with a Wellness Advocate; and 5) $500 small grants for health goals. Metabolic syndrome is the primary endpoint. Stress and depressive severity are secondary endpoints. We measured each construct before, twice during, and at the end of the two-year intervention. Study outcomes, to be published after follow-up data are gathered, will provide evidence of the effectiveness of the combined intervention components of Spirited Life. If successful, the intervention may be considered for use with other clergy and faith populations.


Asunto(s)
Clero , Trastorno Depresivo/terapia , Salud Holística , Síndrome Metabólico/terapia , Obesidad/terapia , Salud Laboral , Religión y Medicina , Estrés Psicológico/terapia , Adulto , Trastorno Depresivo/psicología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Obesidad/psicología , Protestantismo , Estrés Psicológico/psicología , Resultado del Tratamiento
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...