The formation of sulfur trioxide (SO(3)) in coal-fired utility boilers can have negative effects on boiler performance and operation, such as fouling and corrosion of equipment, efficiency loss in the air preheater (APH), increase in stack opacity, and the formation of PM(2.5). Sulfur trioxide can also compete with mercury when bonding with injected activated carbons. Tests in a lab-scale reactor confirmed there are major interferences between fly ash and SO(3) during SO(3) sampling. A modified SO(3) procedure to maximize the elimination of measurement biases, based on the inertial-filter-sampling and the selective-condensation-collecting of SO(3), was applied in SO(3) tests in three full-scale utility boilers. For the two units burning bituminous coal, SO(3) levels starting at 20 to 25 ppmv at the inlet to the selective catalytic reduction (SCR), increased slightly across the SCR, owing to catalytic conversion of SO(2) to SO(3,) and then declined in other air pollutant control device (APCD) modules downstream to approximately 5 ppmv and 15 ppmv at the two sites, respectively. In the unit burning sub-bituminous coal, the much lower initial concentration of SO(3) estimated to be approximately 1.5 ppmv at the inlet to the SCR was reduced to about 0.8 ppmv across the SCR and to about 0.3 ppmv at the exit of the wet flue gas desulfurization (WFGD). The SO(3) removal efficiency across the WFGD scrubbers at the three sites was generally 35% or less. Reductions in SO(3) across either the APH or the dry electrostatic precipitator (ESP) in units burning high-sulfur bituminous coal were attributed to operating temperatures being below the dew point of SO(3).
Background Computed tomography (CT)-guided pulmonary core biopsies of small pulmonary nodules less than 15 millimeters (mm) are challenging for radiologists, and their diagnostic accuracy has been shown to be variable in previous studies. Common complications after the procedure include pneumothorax and pulmonary hemorrhage. The present study compared the diagnostic accuracy of small and large lesions using CT-guided core biopsies and identified the risk factors associated with post-procedure complications. Methods Between January 1, 2016, and December 31, 2017, 198 CT-guided core biopsies performed on 195 patients at our institution were retrospectively enrolled. The lesions were separated into group A (< or = 15 mm) and group B (> 15 mm) according to the longest diameter of the target lesions on CT. Seventeen-gauge introducer needles and 18-gauge automated biopsy instruments were coaxially used for the biopsy procedures. The accuracy and complications, including pneumothorax and pulmonary hemorrhage, of the procedures of each group were recorded. The risk factors for pneumothorax and pulmonary hemorrhage were determined using univariate analysis of variables. Results The diagnostic accuracies of group A (n = 43) and group B (n = 155) were 83.7 % and 96.8 %, respectively ( p = 0.005). The risk factors associated with post-biopsy pneumothorax were longer needle path length from the pleura to the lesion ( p = 0.020), lesion location in lower lobes ( p = 0.002), and patients with obstructive lung function tests ( p = 0.034). The risk factors associated with post-biopsy pulmonary hemorrhage were longer needle path length from the pleura to the lesion ( p < 0.001), smaller lesions ( p < 0.001), non-pleural contact lesions ( p < 0.001), patients without restrictive lung function tests ( p = 0.034), and patients in supine positions ( p < 0.003). Conclusion CT-guided biopsies of small nodules equal to or less than 15 mm using 17-gauge guiding needles and 18-gauge biopsy guns were accurate and safe. The biopsy results of small lesions were less accurate than those of large lesions, but the results were a reliable reference for clinical decision-making. Understanding the risk factors associated with the complications of CT-guided biopsies is necessary for pre-procedural planning and communication.
Two new diamines, 2,4‐diaminotriphenylamine (3) and N‐(2,4‐diaminophenyl)carbazole (4), were synthesized via the cesium fluoride‐mediated aromatic substitution reactions of 1‐fluoro‐2,4‐dinitrobenzene with diphenylamine and carbazole, followed by palladium‐catalyzed hydrazine reduction. Amorphous and soluble aramids having pendent diphenylamino and carbazolyl groups were prepared by the phosphorylation polycondensation of aromatic dicarboxylic acids with diamines 3 and 4, respectively. The aramids derived from diamine 3 had sufficiently high molecular weights to permit the casting of flexible and tough films. They exhibited excellent mechanical properties and moderately high softening temperatures in the 221–298 °C range. However, the reactions of diamine 4 with aromatic diacids gave relatively lower molecular weights products that could not afford flexible films. For a comparative purpose, the parent aramids derived from m‐phenylenediamine and aromatic diacids were also prepared and characterized. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 3302–3313, 2004
IntroductionTreatment options for adults with attention deficit hyperactivity disorder (ADHD) are limited. The study was conducted to confirm the clinically effective and safe dose of methylphenidate hydrochloride modified-release (MPH-LA) in adults with ADHD and evaluate the maintenance of effect of MPH-LA.MethodsThe study consisted of three treatment phases. The double-blind dose-confirmation phase: 9-week double-blind period (3-week titration period, 6-week fixed dose) with randomization to MPH-LA 40, 60, or 80 mg/day or placebo. The real-life dose-optimization phase: a 5-week re-titration period to optimal dose; and the double-blind maintenance of effect phase, a 6-month double-blind randomized placebo-controlled maintenance of effect phase. The three co-primary endpoints were change in Diagnostic and Statistical Manual of Mental Disorders-IV ADHD Rating Scale (DSM-IV ADHD RS) and Sheehan Disability Scale (SDS) total scores from baseline to end of 9-week confirmation phase and the percentage of treatment failures during the 6-month maintenance of effect phase.Results725 of 863 screened patients were randomized to 40 (N = 181), 60 (N = 182), or 80 mg (N = 181) MPH-LA or placebo (N = 181), and 584 (80.6%) completed. 489 (83.7%) of completers were re-randomized to the double-blinded maintenance of effect phase and 235 (48.1%) of them completed. Improvement from baseline in DSM-IV ADHD RS (P < 0.0001 for all comparisons) and SDS (40 mg, P = 0.0003; 60 mg, P = 0.0176; 80 mg, P < 0.0001) total scores was significantly greater vs. placebo for all MPH-LA doses. Treatment failure rate was significantly lower with MPH-LA (21.3%) versus placebo (49.6%) during the 6-month maintenance of effect phase. Safety profile was consistent with the profile for MPH-LA in children; percentage of serious adverse events was comparable between all MPH-LA arms (1.3%) and placebo (1.5%), while percentage of adverse events was higher in MPH-LA arms.ConclusionMPH-LA provided and maintained significant symptomatic and functional improvement in adult ADHD patients.Electronic supplementary materialThe online version of this article (doi:10.1007/s12325-013-0085-5) contains supplementary material, which is available to authorized users.
Attention-deficit/hyperactivity disorder (ADHD) is a chronic psychiatric disorder characterized by hyperactivity and/or inattention and is often associated with a substantial impact on psychosocial functioning. Methylphenidate (MPH), a central nervous system stimulant, is commonly used for pharmacological treatment of adults and children with ADHD. Current practice guidelines recommend optimizing MPH dosage to individual patient needs; however, the clinical benefits of individual dose optimization compared with fixed-dose regimens remain unclear. Here we review the available literature on MPH dose optimization from clinical trials and real-world experience on ADHD management. In addition, we report safety and efficacy data from the largest MPH modified-release long-acting Phase III clinical trial conducted to examine benefits of dose optimization in adults with ADHD. Overall, MPH is an effective ADHD treatment with a good safety profile; data suggest that dose optimization may enhance the safety and efficacy of treatment. Further research is required to establish the extent to which short-term clinical benefits of MPH dose optimization translate into improved long-term outcomes for patients with ADHD.
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