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991.
Lisa A. Jones Jeffrey J. Walline Amber Gaume Marjorie J. Rah Ruth E. Manny David A. Berntsen Monica Chitkara Ailene Kim Nicole Quinn CLIP Study Group 《Contact lens & anterior eye》2009,32(4):157-163
Background
The rate and reasons for discontinuation of contact lens wear by young patients are not well known. The Contact Lenses in Pediatrics (CLIP) Study surveyed participants 3 months after the final study visit to determine the percentage of participants who continued to wear contact lenses after study conclusion. The factors associated with continued contact lens wear and differences in behaviors between the children and teens were also determined to provide insights to practitioners who provide refractive correction for patients in those age groups.Methods
Three months after the CLIP Study completion, participants and parents returned mailed surveys that assessed post-study lens purchase and symptoms related to contact lens wear if contact lenses wear had been continued. Responses were compared between the children and teens using χ2 or Fisher's exact test.Results
Almost 92% of the surveys were returned. Eighty percent of teens’ parents reported purchasing lenses after the study, vs. 63% of the children's parents (p = 0.02). Symptoms reported at the last study visit were not significantly associated with future purchase, though there was a trend towards more light sensitivity in those who did not purchase more contact lenses (23.1% vs. 11.8%). Satisfaction with contact lenses was high among both those purchasing additional contact lenses and those who did not. Both children and teens reported similar frequencies of symptoms such as burning, itching or tearing eyes 3 months following study completion. Teens reported having contact-lens-related dry eyes more frequently than children.Conclusions
A large proportion of children and an even higher proportion of teens continued wearing their lenses 3 months after completing the CLIP Study. Children and teens reported similar contact lens comfort and low frequencies of most symptoms, though teens experienced more dry-eye symptoms. Overall, reports of symptoms in this sample were lower than had been reported in adult populations by other investigators. 相似文献992.
LC/MS/MS detection of fungicide guazatine residues for quality assessment of commercial citrus fruit
Monica Scordino Leonardo Sabatino Pasqualino Traulo Giacomo Gagliano Maria Gargano Valentina Pantò Grazia Laura Gambino 《European Food Research and Technology》2008,227(5):1339-1347
An analytical protocol was developed for investigating guazatine occurrence in citrus fruit with the aim of controlling the
import of treated fruits in countries where the use of this fungicide is forbidden. The main constituents of guazatine mixture
(GN, GG, GNG, GGN, GGG, GGGN and GGGG) and the internal standard (dodine) were separated by high performance liquid chromatography
using a hydrophilic end-capped Aquasil C18 column and detected by ESI/MS/MS of parent ions, operating in positive mode. Extraction from citrus peels was performed with
1% HCOOH in water/acetone (1:2 v/v). The analytical method was statistically validated on three of the main constituents (GG,
GGN and GGG) representing more than 65% of the total content. The regression lines, ranging from 0.100 to 3.750 mg/L of total
guazatine, showed r
2 > 0.990. Recoveries of about 81, 90 and 104% were obtained on average for the fortification level of 0.010, 0.035 and 0.060 mg/kg,
respectively; the relative standard deviations ranged from 2 to 8% (n = 6). The limit of detection was below 0.0050 mg/kg, while the limit of quantification did not exceed 0.0065 mg/kg. The method
was successfully applied to 77 samples of extra-European citrus fruit collected in the Italian market during the summer 2007.
The results demonstrated that 64% of the investigated citrus samples contained guazatine over the residue limit value of 0.010 mg/kg
for not allowed pesticides, evidencing the alarming illicit employ of this fungicide in citrus post-harvest treatments. 相似文献
993.
De Schamphelaire L Van den Bossche L Dang HS Höfte M Boon N Rabaey K Verstraete W 《Environmental science & technology》2008,42(8):3053-3058
Living plants transport substantial amounts of organic material into the soil. This process, called rhizodeposition, provides the substrate for the rhizospheric microbial community. In this study, a laboratory-scale sediment microbial fuel cell, of which the anode is positioned in the rhizosphere of the rice plants, is used to microbially oxidize the plant-derived organics. An electrical current was generated through the in situ oxidation of rhizodeposits from living rice plants. The electrical power output of a sediment microbial fuel cell was found to be a factor 7 higher in the presence of actively growing plants. This process offers the potential of light-driven power generation from living plants in a nondestructive way. Sustainable power productions up to 330 W ha(-1) could be attributed to the oxidation of the plant-derived compounds. 相似文献
994.
Grandlic CJ Mendez MO Chorover J Machado B Maier RM 《Environmental science & technology》2008,42(6):2079-2084
Eolian dispersion of mine tailings in arid and semiarid environments is an emerging global issue for which economical remediation alternatives are needed. Phytostabilization, the revegetation of these sites with native plants, is one such alternative. Revegetation often requires the addition of bulky amendments such as compost which greatly increases cost. We report the use of plant growth-promoting bacteria (PGPB) to enhance the revegetation of mine tailings and minimize the need for compost amendment. Twenty promising PGPB isolates were used as seed inoculants in a series of greenhouse studies to examine revegetation of an extremely acidic, high metal contenttailings sample previously shown to require 15% compost amendment for normal plant growth. Several isolates significantly enhanced growth of two native species, quailbush and buffalo grass, in tailings. In this study, PGPB/compost outcomes were plant specific; for quailbush, PGPB were most effective in combination with 10% compost addition while for buffalo grass, PGPB enhanced growth in the complete absence of compost. Results indicate that selected PGPB can improve plant establishment and reduce the need for compost amendment. Further, PGPB activities necessary for aiding plant growth in mine tailings likely include tolerance to acidic pH and metals. 相似文献
995.
Rutile-doped hematite xTiO2(1 ? x)α-Fe2O3 (x = 0.0–1.0) nanostructures were synthesized using mechanochemical activation by ball milling. Their complex structural, magnetic and thermal properties were characterized by X-ray diffraction, Mössbauer spectroscopy and simultaneous DSC–TGA. XRD patterns yielded the dependence of lattice parameters and grain size as a function of ball milling time. For the molar concentrations x = 0.1 and 0.3, the Mössbauer spectra were fitted with one, two, three or four sextets, corresponding to the degree of Ti ion substitution of Fe ions in hematite lattice. After 12 h of ball milling, the completion of Ti ion substitution of Fe ions in hematite lattice occurs for x = 0.1 and 0.3. For x = 0.5 and 0.7, Mössbauer spectra fitting required sextets and a quadrupole-split doublet, representing Fe ions substituting Ti ions in the rutile lattice. The completion of Fe ion substitution of Ti ions in rutile lattice was not observed, as indicated by XRD patterns and Mössbauer spectra for these two molar concentrations. Simultaneous DSC–TGA measurements revealed that the mechanochemical activation by ball milling has a strong effect on the thermal behavior of this nanostructure system. The enthalpy dropped dramatically after 2 h of milling time, indicating the strong solid–solid interactions between TiO2 and α-Fe2O3 after ball milling. The change in weight loss of hematite was caused by the decrease of grain size and ion substitutions between Fe and Ti after mechanochemical activation. 相似文献
996.
Stoian Petrescu Camelia Petre Monica Costea Octavian Malancioiu Nicolae Boriaru Alexandru Dobrovicescu Michel Feidt Charles Harman 《Energy》2010
The objective of this paper is to develop a methodology to determine how many houses could be fueled from the solar energy captured by a number of solar Stirling modules (with a fixed dish area per module) and also to determine the minimum necessary area of the fuel cell to ensure the amount of power needed to meet daily energy use requirements. The detailed method includes the effect of the fuel cell efficiency function on the power consumption of the user. Experimental data from our laboratory are used to determine the fuel cell efficiency as a function of the electric current density for a specific power demand. As an illustrative example, the analysis is applied to a residential area having a specific electrical demand. Using the developed method, the number of houses that could be fueled directly by the stored hydrogen is determined, and also the minim fuel cell area required. 相似文献
997.
Lang Jason M.; Ford Julian D.; Fitzgerald Monica M. 《Canadian Metallurgical Quarterly》2010,47(4):554
The shift toward dissemination of evidence-based practices has led to many questions about who is appropriate for a particular treatment model, particularly with complex clients, in diverse community settings, and when multiple evidence-based models have overlapping target populations. Few research-based tools exist to facilitate these clinical decisions. The research on trauma-focused cognitive–behavioral therapy (TF-CBT), an evidence-based treatment for children suffering from posttraumatic stress reactions, is reviewed to inform development of an algorithm to assist clinicians in determining whether a particular client is appropriate for TF-CBT. Recommendations are made for future research that will facilitate matching TF-CBT and other evidence-based practices to particular child clients. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
998.
Webb Monica S.; Baker Elizabeth A.; Rodríguez de Ybarra Denise 《Canadian Metallurgical Quarterly》2010,24(2):333
Previous research has highlighted the importance of cultural relevance in health risk communications, including tobacco interventions. However, few studies have examined the active components of smoking cessation messages targeting low-income African American smokers. This study tested the influence of message content and culturally specific framing in a sample of adult smokers. In a 2 × 2 factorial experiment, 243 African American smokers (M = 19 cigarettes/day) recruited from the community (55% women; mean age = 43 years) were randomly assigned to 1 of 4 conditions: culturally specific smoking messages, standard smoking messages, culturally specific exercise/weight messages, or standard exercise/weight messages. The primary outcome measures were theoretical antecedents to behavior change, including risk perceptions (general, personal, and culturally specific), readiness to quit smoking, and smoking-related knowledge. The results showed that the smoking messages produced greater culturally specific risk perceptions, readiness to quit smoking, and smoking-related knowledge. The culturally specific messages produced greater personal risk perceptions and intentions to quit. Culturally specific risk perceptions were most affected by culturally specific smoking messages. Findings support the roles of message content and culturally specific framing in the efficacy of brief written interventions for smoking cessation in this population. Future research is needed to examine the influence of these constructs on behavior change. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
999.
Ulibarri Monica D.; Strathdee Steffanie A.; Lozada Remedios; Magis-Rodriguez Carlos; Amaro Hortensia; O'Campo Patricia; Patterson Thomas L. 《Canadian Metallurgical Quarterly》2010,2(4):318
Intimate partner violence (IPV) has been associated with greater vulnerability to HIV infection among women. We examined prevalence and correlates of IPV among female sex workers (FSWs) in Tijuana and Ciudad Juarez, two large Mexico–U.S. border cities in which HIV prevalence is rising. Participants were 300 FSWs with a current spouse or a steady partner. Participants' mean age was 33 years, and mean number of years as a sex worker was 6. The prevalence of IPV in the past 6 months among participants was 35%. Using multivariate logistic regression, factors independently associated with IPV included having experienced abuse as a child, a partner who had sex with someone else, and lower sexual relationship power. Our findings suggest the need for previous abuse screening and violence prevention services for FSWs in the Mexico–U.S. border region. Careful consideration of relationship dynamics such as infidelity and relationship power is warranted when assessing for IPV risk. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
1000.