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Selected AbstractsBiosensors Based on Aligned Carbon Nanotubes Coated with Inherently Conducting PolymersELECTROANALYSIS, Issue 13 2003Mei Gao Abstract The use of multiwalled aligned carbon nanotubes provides a novel electrode platform for inherently conducting polymer based biosensors. The example used here to highlight the usefulness of such a platform is the polypyrrole based glucose oxidase system for detection of glucose. The use of these three dimensional electrodes offers advantages in that large accessible enzyme loadings can be obtained within an ultrathin layer. It has also been found that the detection of H2O2 at these new electrode structures containing iron loaded nanotube tips can be achieved at low anodic potentials. The result is a sensitive and selective glucose sensor. [source] Zolmitriptan Intranasal: A Review of the Pharmacokinetics and Clinical EfficacyHEADACHE, Issue 1 2006Peter J. Goadsby MD Migraine is a common disabling neurological disorder, associated with headache, nausea, and on occasions vomiting. Zolmitriptan is a widely available serotonin 5HT1B/1D receptor agonist with a long track record in clinical studies and in the treatment of acute migraine. A nasal formulation has been developed that has clear evidence for local absorption, resulting in plasma drug concentrations within 2 minutes of dosing, central nervous system penetration 3 minutes later, and a significant efficacy benefit versus placebo 10 to 15 minutes after dosing. Intranasal zolmitriptan offers advantages to migraineurs, particularly those seeking a more rapid onset of effect without wishing to self-inject, or those with gastrointestinal upset. The comparison of pharmacokinetic and clinical data available from different formulations of zolmitriptan contributes both to the understanding of its mode of action and the characteristics required of an acute migraine treatment if it is to meet patient needs. [source] Technical issues affecting the implementation of US Environmental Protection Agency's proposed fish tissue-based aquatic criterion for selenium,INTEGRATED ENVIRONMENTAL ASSESSMENT AND MANAGEMENT, Issue 4 2007A Dennis Lemly Abstract The US Environmental Protection Agency is developing a national water quality criterion for selenium that is based on concentrations of the element in fish tissue. Although this approach offers advantages over the current water-based regulations, it also presents new challenges with respect to implementation. A comprehensive protocol that answers the "what, where, and when" is essential with the new tissue-based approach in order to ensure proper acquisition of data that apply to the criterion. Dischargers will need to understand selenium transport, cycling, and bioaccumulation in order to effectively monitor for the criterion and, if necessary, develop site-specific standards. This paper discusses 11 key issues that affect the implementation of a tissue-based criterion, ranging from the selection of fish species to the importance of hydrological units in the sampling design. It also outlines a strategy that incorporates both water column and tissue-based approaches. A national generic safety-net water criterion could be combined with a fish tissue,based criterion for site-specific implementation. For the majority of waters nationwide, National Pollution Discharge Elimination System permitting and other activities associated with the Clean Water Act could continue without the increased expense of sampling and interpreting biological materials. Dischargers would do biotic sampling intermittently (not a routine monitoring burden) on fish tissue relative to the fish tissue criterion. Only when the fish tissue criterion is exceeded would a full site-specific analysis including development of intermedia translation factors be necessary. [source] A genetic-based neuro-fuzzy controller for blind equalization of time-varying channelsINTERNATIONAL JOURNAL OF ADAPTIVE CONTROL AND SIGNAL PROCESSING, Issue 7 2008Siba Prasada Panigrahi Abstract This paper presents a neuro-fuzzy network (NFN) where all its parameters can be tuned simultaneously using genetic algorithms (GAs). The approach combines the merits of fuzzy logic theory, neural networks and GAs. The proposed NFN does not require a priori knowledge about the system and eliminates the need for complicated design steps such as manual tuning of input,output membership functions, and selection of fuzzy rule base. Although, only conventional GAs have been used, convergence results are very encouraging. A well-known numerical example derived from literature is used to evaluate and compare the performance of the network with other equalizing approaches. Simulation results show that the proposed neuro-fuzzy controller, all parameters of which have been tuned simultaneously using GAs, offers advantages over existing equalizers and has improved performance. From the perspective of application and implementation, this paper is very interesting as it provides a new method for performing blind equalization. The main contribution of this paper is the use of learning algorithms to train a feed-forward neural network for M-ary QAM and PSK signals. This paper also provides a platform for researchers of the area for further development. Copyright © 2008 John Wiley & Sons, Ltd. [source] Welding and Marking of Plastics with LasersLASER TECHNIK JOURNAL, Issue 5 2010New absorbers increase possibilities for application Today laser radiation as a tool for The Authors welding, cutting and marking in manufacturing of plastic components and products has achieved a good market acceptance. It offers an alternative to conventional processes such as ultrasonic, vibration or friction welding, mechanical cutting, milling or water jet cutting, tampon printing or ink jet printing. Main advantages for laser marking are flexibility and a contact free process [1]. Laser welding of plastics offers advantages in case of cleanness of processed components, low thermal and mechanical stress to components and inner sensitive parts as well as flexibility [2]. Although laser beam welding seems to be a relatively expensive processing method, savings can be achieved by entirely consideration of production process and logistics. [source] In Defense of Asbestos Tort Litigation: Rethinking Legal Process Analysis in a World of Uncertainty, Second Bests, and Shared Policy-Making ResponsibilityLAW & SOCIAL INQUIRY, Issue 1 2009Jeb Barnes A central question in American policy making is when should courts address complex policy issues, as opposed to defer to other forums? Legal process analysis offers a standard answer. It holds that judges should act when adjudication offers advantages over other modes of social ordering such as contracts, legislation, or agency rule making. From this vantage, the decision to use common law adjudication to address a sprawling public health crisis was a terrible mistake, as asbestos litigation has come to represent the very worst of mass tort litigation. This article questions this view, arguing that legal process analysis distorts the institutional choices underlying the American policy-making process. Indeed, once one considers informational and political constraints, as well as how the branches of government can fruitfully share policy-making functions, the asbestos litigation seems a reasonable and, in some ways, exemplary, use of judicial power. [source] Treatment of dermatophyte onychomycosis with three pulses of terbinafine (500 mg day,1 for a week)MYCOSES, Issue 1 2009Y. Takahata Summary We assessed the safety and efficacy of pulse therapy with terbinafine tablets in 55 patients with dermatophytic onychomycosis. One pulse consisted of oral terbinafine tablets (500 mg day,1) given for 1 week usually followed by a 3-week interval. This regimen was repeated twice. Topical 1% terbinafine cream was applied daily. Efficacy was assessed based on both clinical and mycological examinations 1 year after treatment initiation. We observed a complete cure in 41 patients (74.5%), marked improved in three patients (5.6%), slight improvement in three patients (5.6%) and drop out in six patients (10.7%). Two patients (3.6%) discontinued terbinafine because of gastrointestinal disturbance (one patient) and drug-induced eruption (one patient). No patient had abnormal laboratory findings, including liver function tests. In summary, a regimen of three pulses of terbinafine therapy given daily for 1 week in combination with topical application of terbinafine cream appears to be safe and effective in treating dermatophytic onychomycosis and offers advantages in convenience and cost-effectiveness compared with continuous dosing. [source] Endoscopic endonasal surgery for petrous apex lesionsTHE LARYNGOSCOPE, Issue 1 2009Adam M. Zanation MD Abstract Background: Endoscopic endonasal approaches to the ventral skull base are categorized based on their orientation in coronal and sagittal planes. For all of these approaches, the sphenoid sinus is the starting point, and provides orientation to important vascular and neural structures. Surgical approaches to the petrous apex include 1) a medial approach, 2) a medial approach with internal carotid artery (ICA) lateralization, and 3) a transpterygoid infrapetrous approach (inferior to the petrous internal carotid artery). The choice of a surgical approach depends on the relationship of the lesion to the internal carotid artery (medial or inferior), degree of medial expansion, and pathology. The purpose of this paper is to discuss the anatomic and technical features of endoscopic surgical approaches to the petrous apex, provide a new classification for approaches that focuses on the relationship of the lesion to the petrous internal carotid artery, and provide outcomes data on our first 20 endoscopic petrous apex approaches. Methods: A retrospective clinical outcome study of endoscopic petrous apex surgeries was performed at the University of Pittsburgh Medical Center. The medical records from patients with endoscopic endonasal approaches to isolated petrous apex lesions were reviewed for demographics, diagnoses, presentation, endoscopic approach, and clinical outcomes. Patients with lesions that extended into the petrous apex but were not isolated to the petrous apex were excluded (e.g., clival chordoma with extension into the petrous apex). Results: Twenty patients were included in the analysis: 13 inflammatory cystic lesions (9 cholesterol granulomas and four petrous apicitis) and 7 solid lesions. Chondrosarcoma was the most common solid petrous apex lesion in our series. Twelve of 13 cystic lesions were drained endoscopically (one surgery was aborted early in the series). All drained patients had resolution of presenting symptoms. One patient had closure of the outflow tract without return of symptoms and one patient had revision endoscopic drainage due to scarring and neo-osteogenesis and return of unilateral headache. No carotid injuries and no new cranial neuropathies occurred perioperatively. The advantages and limitations of the medial transsphenoidal approaches (with and without carotid mobilization) and the transpterygoid infrapetrous approach are discussed. Conclusions: The endoscopic endonasal approach to petrous apex lesions is safe and effective for appropriately selected patients in the hands of experienced endoscopic skull base surgeons. If offers advantages of removing the hearing and facial nerve risks from the transtemporal/transcranial approaches and allows for a larger and more natural drainage pathway into the sinuses. Laryngoscope, 119:19,25, 2009 [source] Adolescents' perceptions of a health survey using multimedia computer-assisted self-administered interviewAUSTRALIAN AND NEW ZEALAND JOURNAL OF PUBLIC HEALTH, Issue 6 2001Peter D. Watson Objective: To ascertain young people's perceptions of an adolescent health survey when administered by multimedia computer assisted self-administered Interview (M-CASI) through analysis of (1) questionnaire item responses and (2) focus group interviews. Methodology: Setting: Auckland, New Zealand, 1999. Study type: Pilot testing of a 488-item branching questionnaire delivered using a youth-oriented and user-friendly M-CASI interface in a variety of settings using both desktop and laptop computers. Post pilot focus groups of participants identifying their perceptions and experiences of the survey. Sample: 110 school students aged 12 to 18 years. Results: The mean number of questions answered by participants was 316 with the median time to completion being 48 minutes. On average 65% of the total number of questions were seen and of these 1.5% were deliberately not answered. A high level of acceptability and enjoyment of M-CASI was found in the analysis of focus group responses and agreed with the item responses relating to M-CASI within the questionnaire itself. Participants identified privacy and confidentiality as being particularly important for the honesty of their responses. The passive matrix screens of the computers were popular as they could only be viewed from in front. Conclusions: M-CASI is an acceptable instrument for the administration of a youth health survey. Laptop computers with passive matrix screens are able to enhance perceptions of privacy and confidentiality, which may improve honesty of responses. Implications: M-CASI is now feasible and offers advantages in health surveying. [source] Influence of nonspecific brain and plasma binding on CNS exposure: implications for rational drug discoveryBIOPHARMACEUTICS AND DRUG DISPOSITION, Issue 8 2002J. Cory Kalvass Abstract Relative plasma, brain and cerebrospinal fluid (CSF) exposures and unbound fractions in plasma and brain were examined for 18 proprietary compounds in rats. The relationship between in vivo brain-to-plasma ratio and in vitro plasma-to-brain unbound fraction (fu) was examined. In addition, plasma fu and brain fu were examined for their relationship to in vivo CSF-to-plasma and CSF-to-brain ratios, respectively. Findings were delineated based on the presence or absence of active efflux. Finally, the same comparisons were examined in FVB vs. MDR 1a/1b knockout mice for a selected P-glycoprotein (Pgp) substrate. For the nine compounds without indications of active efflux, predictive correlations were observed between ratios of brain-to-plasma exposure and plasma-to-brain fu (r2 = 0.98), CSF-to-brain exposure vs. brain fu (r2 = 0.72), and CSF-to-plasma exposure vs. plasma fu (r2 = 0.82). For the nine compounds with indications of active efflux, nonspecific binding data tended to over predict the brain-to-plasma and CSF-to-plasma exposure ratios. Interestingly, CSF-to-brain exposure ratio was consistently under predicted by brain fu for this set. Using a select Pgp substrate, it was demonstrated that the brain-to-plasma exposure ratio was identical to that predicted by plasma-to-brain fu ratio in MDR 1a/1b knockout mice. In FVB mice, plasma-to-brain fu over predicted brain-to-plasma exposure ratio to the same degree as the difference in brain-to-plasma exposure ratio between MDR 1a/1b and FVB mice. Consistent results were obtained in rats, suggesting a similar kinetic behavior between species. These data illustrate how an understanding of relative tissue binding (plasma, brain) can allow for a quantitative examination of active processes that determine CNS exposure. The general applicability of this approach offers advantages over species- and mechanism-specific approaches. Copyright © 2002 John Wiley & Sons, Ltd. [source] Microwave-Assisted Kolbe-Schmitt Synthesis Using Ionic Liquids or Dimcarb as Reactive SolventsCHEMICAL ENGINEERING & TECHNOLOGY (CET), Issue 11 2009A. Stark Abstract The activation of relatively inert carbon dioxide as a building block for organic products is of interest from both ecological and chemical points of view. One of the few industrially relevant processes using CO2 is the Kolbe-Schmitt synthesis. Two strategies to obtain the carboxylated product 2,4-dihydroxybenzoic acid from resorcinol are presented: both Dimcarb and hydrogencarbonate- or methylcarbonate-based ionic liquids are employed as reactive solvents in a microwave-assisted reaction. Reaction optimization shows that the ionic liquids are more reactive than Dimcarb. However, Dimcarb offers advantages with regard to ecological aspects, such as the Global Warming and Human Toxicity Potential and the Cumulative Energy Demand, which were assessed as part of the process development. [source] | ||||||||||||||||