832 resultados para Impact of compositional constraints-on correlation and covariance
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Pharmaceuticals are useful tools to prevent and treat human and animal diseases. Following administration, a significant fraction of pharmaceuticals is excreted unaltered into faeces and urine and may enter the aquatic ecosystem and agricultural soil through irrigation with recycled water, constituting a significant source of emerging contaminants into the environment. Understanding major factors influencing their environmental fate is consequently needed to value the risk, reduce contamination, and set up bioremediation technologies. The antiviral drug Tamiflu (oseltamivir carboxylate, OC) has received recent attention due to the potential use as a first line defence against H5N1 and H1N1 influenza viruses. Research has shown that OC is not removed during conventional wastewater treatments, thus having the potential to enter surface water bodies. A series of laboratory experiments investigated the fate and the removal of OC in surface water systems in Italy and Japan and in a municipal wastewater treatment plant. A preliminary laboratory study investigated the persistence of the active antiviral drug in water samples from an irrigation canal in northern Italy (Canale Emiliano Romagnolo). After an initial rapid decrease, OC concentration slowly decreased during the remaining incubation period. Approximately 65% of the initial OC amount remained in water at the end of the 36-day incubation period. A negligible amount of OC was lost both from sterilized water and from sterilized water/sediment samples, suggesting a significant role of microbial degradation. Stimulating microbial processes by the addition of sediments resulted in reduced OC persistence. Presence of OC (1.5 μg mL-1) did not significantly affect the metabolic potential of the water microbial population, that was estimated by glyphosate and metolachlor mineralization. In contrast, OC caused an initial transient decrease in the size of the indigenous microbial population of water samples. A second laboratory study focused on basic processes governing the environmental fate of OC in surface water from two contrasting aquatic ecosystems of northern Italy, the River Po and the Venice Lagoon. Results of this study confirmed the potential of OC to persist in surface water. However, the addition of 5% of sediments resulted in rapid OC degradation. The estimated half-life of OC in water/sediment of the River Po was 15 days. After three weeks of incubation at 20 °C, more than 8% of 14C-OC evolved as 14CO2 from water/sediment samples of the River Po and Venice Lagoon. OC was moderately retained onto coarse sediments from the two sites. In water/sediment samples of the River Po and Venice Lagoon treated with 14C-OC, more than 30% of the 14C-residues remained water-extractable after three weeks of incubation. The low affinity of OC to sediments suggests that the presence of sediments would not reduce its bioavailability to microbial degradation. Another series of laboratory experiments investigated the fate and the removal of OC in two surface water ecosystems of Japan and in the municipal wastewater treatment plant of the city of Bologna, in Northern Italy. The persistence of OC in surface water ranged from non-detectable degradation to a half-life of 53 days. After 40 days, less than 3% of radiolabeled OC evolved as 14CO2. The presence of sediments (5%) led to a significant increase of OC degradation and of mineralization rates. A more intense mineralization was observed in samples of the wastewater treatment plant when applying a long incubation period (40 days). More precisely, 76% and 37% of the initial radioactivity applied as 14C-OC was recovered as 14CO2 from samples of the biological tank and effluent water, respectively. Two bacterial strains growing on OC as sole carbon source were isolated and used for its removal from synthetic medium and environmental samples, including surface water and wastewater. Inoculation of water and wastewater samples with the two OC-degrading strains showed that mineralization of OC was significantly higher in both inoculated water and wastewater, than in uninoculated controls. Denaturing gradient gel electrophoresis and quantitative PCR analysis showed that OC would not affect the microbial population of surface water and wastewater. The capacity of the ligninolytic fungus Phanerochaete chrysosporium to degrade a wide variety of environmentally persistent xenobiotics has been largely reported in literature. In a series of laboratory experiments, the efficiency of a formulation using P. chrysosporium was evaluated for the removal of selected pharmaceuticals from wastewater samples. Addition of the fungus to samples of the wastewater treatment plant of Bologna significantly increased (P < 0.05) the removal of OC and three antibiotics, erythromycin, sulfamethoxazole, and ciprofloxacin. Similar effects were also observed in effluent water. OC was the most persistent of the four pharmaceuticals. After 30 days of incubation, approximately two times more OC was removed in bioremediated samples than in controls. The highest removal efficiency of the formulation was observed with the antibiotic ciprofloxacin. The studies included environmental aspects of soil contamination with two emerging veterinary contaminants, such as doramectin and oxibendazole, wich are common parasitic treatments in cattle farms.
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Objectives We compared the angiographic and long-term clinical outcomes of patients with and without overlap of drug-eluting stents (DES). Background DES overlap has been associated with delayed healing and increased inflammation in experimental studies, but its impact on clinical outcome is not well established. Methods We analyzed the angiographic and clinical outcomes of 1,012 patients treated with DES in the SIRTAX (Sirolimus-Eluting Versus Paclitaxel-Eluting Stents for Coronary Revascularization) trial according to the presence or absence of stent overlap and the number of stents per vessel: 134 (13.2%) patients with multiple DES in a vessel with overlap, 199 (19.7%) patients with multiple DES in a vessel without overlap, and 679 (67.1%) patients with 1 DES per vessel. Results Angiographic follow-up at 8 months showed an increased late loss in DES overlap patients (0.33 ± 0.61 mm) compared with the other groups (0.18 ± 0.43 mm and 0.15 ± 0.38 mm, p < 0.01). The smallest minimal lumen diameter was located at the zone of stent overlap in 17 (68%) of 25 patients with stent overlap who underwent target lesion revascularization. Major adverse cardiac events were more common in patients with DES overlap (34 events, 25.4%) than in the other groups (42 events, 21.1% and 95 events, 14.0%) at 3 years (p < 0.01). Both the risk of target lesion revascularization (20.2% vs. 16.1% vs. 9.7%, p < 0.01) and the composite of death or myocardial infarction (17.2% vs. 14.1% vs. 9.1%, p = 0.01) were increased in patients with DES overlap compared with the other groups. Conclusions DES overlap occurs in >10% of patients undergoing percutaneous coronary intervention in routine clinical practice and is associated with impaired angiographic and long-term clinical outcome, including death or myocardial infarction. (Sirolimus-Eluting Versus Paclitaxel-Eluting Stents for Coronary Revascularization; NCT00297661).
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BACKGROUND: Secondary intraocular lens (IOL) implantation is exposed to an increased risk of complications, including endophthalmitis and retinal detachment. The present analysis compares the outcomes and complications experienced in our own series of patients. PATIENTS AND METHODS: We retrospectively reviewed a consecutive series of secondary posterior chamber IOL implantations performed in a single centre, two surgeon setting over a period of 8 years and with a follow up-time of at least 4 months. RESULTS: Between 1997 and 2005, 75 patients received a sulcus-supported secondary IOL without suture fixation, whereas suture fixation was required in 137 instances. Visual acuity improved in both groups (group 1: from 0.36 +/- 0.39 (0.01-1.2) to 0.73 +/- 0.33 (0.02-1.0; p = 0.18); group 2: from 0.33 +/- 0.34 (0.02-1.0) to 0.46 +/- 0.33 (0.01-1.0; p = 0.006), but more pronounced in eyes not requiring suture fixation (p = 0.012). IOL placement was more likely to be combined with endophacoemulsification in the not suture-fixed IOLs (12.7 vs. 5.3 %). In contrast, retinal tears (10.6 vs. 8.6 %, respectively) and retinal detachment (5.3 vs. 2.2 %, respectively) were equally distributed. In the early postoperative phase, IOP was lower in suture-fixed eyes, which showed a higher incidence of minor intraocular haemorrhages and cystoid macular edema (5.3 vs. 8.0 %); late complications up to 5 years postoperatively were equally distributed. CONCLUSION: A preoperatively less complicated anterior segment situation and a lower incidence of postoperative macular edema may account for a better visual outcome after placement of a sulcus supported IOLs without suturing. If required, suture fixation may be performed without exposing the eye to an increased risk of late postoperative complications.
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OBJECTIVES: We assessed the impact of vessel size on outcomes of stenting with biolimus-eluting degradable polymer stent (BES) and sirolimus-eluting permanent polymer stent (SES) within a randomized multicenter trial (LEADERS). BACKGROUND: Stenting of small vessels might be associated with higher rates of adverse events. METHODS: "All-comer" patients (n = 1,707) were randomized to BES and SES. Post-hoc-stratified analysis of angiographic and clinical outcomes at 9 months and 1 year, respectively, was performed for vessels with reference diameter
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The work environment characteristics of job stress, job variety, job autonomy, and supervision are theorized to affect the job satisfaction and organizational commitment of social and human service workers. Most research to date has focused upon the impact of these variables on job satisfaction, with little attention being paid to organizational commitment. To determine the effects these characteristics have on both job satisfaction and organizational commitment, data from a survey of social and human service employees across Northwest Ohio were examined. In Ordinary Least Squares regression, all four job characteristics had a significant impact on job satisfaction, while only job variety and supervision had statistically significant effects on organizational commitment.
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We investigate whether the dependence of immigrants on welfare benefits leads to opposition to further immigration by natives and immigrants in a pooled cross-section of 21 European countries for the 2004-2010 period. Explicitly controlling for the dependence of immigrants and natives on benefits we find that higher benefit take-up rates among immigrants than among natives lead to less favourable attitudes of natives towards immigration. Interestingly, we do not find similar stylised facts for immigrants' attitudes towards immigration.
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We investigate whether the dependence of immigrants on welfare benefits leads to opposition to further immigration by natives and immigrants in a pooled cross-section of 21 European countries for the 2004-2010 period. Explicitly controlling for the dependence of immigrants and natives on benefits we find that higher benefit take-up rates among immigrants than among natives lead to less favourable attitudes of natives towards immigration. Interestingly, we do not find similar stylised facts for immigrants' attitudes towards immigration.
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Prostate cancer (CaP) is the most diagnosed non-cutaneous malignancy and the second leading cause of cancer mortality among United States males. Major racial disparities in incidence, survival, as well as treatment persist. The mortality is three times higher among African Americans (AAs) compared with Caucasians. Androgen carcinogenesis has been persistently implicated but results are inconsistent; and hormone manipulation has been the main stay of treatment for metastatic disease, supportive of the androgen carcinogenesis. The survival disadvantage of AAs has been attributed to the differences in socioeconomic factors (SES), tumor stage, and treatment. We hypostasized that HT prolongs survival in CaP and that the racial disparities in survival is influenced by variation in HT and primary therapies as well as SES. To address these overall hypothesis, we first utilized a random-effect meta-analytic design to examine evidence from randomized trials on the efficacy of androgen deprivation therapy in localized and metastatic disease, and assessed, using Cox proportional hazards models, the effectiveness of HT in prolonging survival in a large community-based cohort of older males diagnosed with local/regional CaP. Further we examined the role of HT and primary therapies on the racial disparities in CaP survival. The results indicated that adjuvant HT compared with standard care alone is efficacious in improving overall survival, whereas HT has no significant benefit in the real world experience in increasing the overall survival of older males in the community treated for local/regional disease. Further, racial differences in survival persist and were explained to some extent by the differences in the primary therapies (radical prostatectomy, radiation and watchful waiting) and largely by SES. Therefore, given the increased used of hormonal therapy and the cost-effectiveness today, more RCTs are needed to assess whether or not survival prolongation translates to improved quality of life, and to answer the research question on whether or not the decreased use of radical prostatectomy by AAs is driven by the Clinicians bias or AAs's preference of conservative therapy and to encourage AAs to seek curative therapies, thus narrowing to some degree the persistent mortality disparities between AAs and Caucasians. ^
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An apparatus was developed to project spinning golf balls directly onto golf greens. This employed a modified baseball/practice machine with two counter-rotating pneumatic wheels. The speed of the wheels could be varied independently allowing backspin to be given to the ball. The ball was projected into a darkened enclosure where the motion of the ball before and after impacting with the turf was recorded using a still camera and a stroboscope. The resulting photographs contained successive images of the ball on a single frame of film. The apparatus was tested on eighteen golf courses resulting in 721 photographs of impacts. Statistical analysis was carried out on the results of the photographs and from this, two types of green emerged. On the first, the ball tended to rebound with topspin, while on the second, the ball retained backspin after impact if the initial backspin was greater than about 350 rads-1. Eleven tests were devised to determine the characteristics of greens and statistical techniques were used to analyse the relationships between these tests. These showed the effects of the green characteristics on ball/turf impacts. It was found that the ball retained backspin on greens that were freely drained and had less than 60% of Poa annua (annual meadow grass) in their swards. Visco-elastic models were used to simulate the impact of the ball with the turf. Impacts were simulated by considering the ball to be rigid and the turf to be a two layered system consisting of springs and dampers. The model showed good agreement with experiment and was used to simulate impacts from two different shots onto two contrasting types of green.
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Objective: To determine the efficacy of cholinesterase inhibitors (ChEIs) in improving the behavioral and psychological symptoms of dementia (BPSD) in patients with Alzheimer’s disease (AD). Data sources: We searched MEDLINE, Cochrane Registry, and the Cumulative Index to Nursing and Allied Health Literature (CINAHL) from 1966 to 2007. We limited our search to English Language, full text, published articles and human studies. Data extraction: We included randomized, double-blind, placebo-controlled trials evaluating the efficacy of donepezil, rivastigmine, or galantamine in managing BPSD displayed by AD patients. Using the United States Preventive Services Task Force (USPSTF) guidelines, we critically appraised all studies and included only those with an attrition rate of less than 40%, concealed measurement of the outcomes, and intention to treat analysis of the collected data. All data were imputed into pre-defined evidence based tables and were pooled using the Review Manager 4.2.1 software for data synthesis. Results: We found 12 studies that met our inclusion criteria but only nine of them provided sufficient data for the meta-analysis. Among patients with mild to severe AD and in comparison to placebo, ChEIs as a class had a beneficial effects on reducing BPSD with a standard mean difference (SMD) of -0.10 (95% confidence interval [CI]; -0.18, -0.01) and a weighted mean difference (WMD) of -1.38 neuropsychiatry inventory point (95% CI; -2.30, -0.46). In studies with mild AD patients, the WMD was -1.92 (95% CI; -3.18, -0.66); and in studies with severe AD patients, the WMD was -0.06 (95% CI; -2.12, +0.57). Conclusion: Cholinesterase inhibitors lead to a statistical significant reduction in BPSD among patients with AD, yet the clinical relevance of this effect remains unclear.