Hydrogen Sensors Based on Flexible Carbon Nanotube-Palladium Composite Sheets Integrated with Ripstop Fabric.

This work describes the design and fabrication of free-standing carbon nanotube-palladium (CNT-Pd) composite sheets for hydrogen gas sensing. The CNT-Pd composites were made by electroplating palladium onto a solvent-densified and oxygen plasma-treated CNT sheet. The latter was prepared using high purity CNTs drawn from a dense, vertically aligned array grown by chemical vapor deposition on silicon substrates. The CNT-Pd sheets were characterized by energy-dispersive spectroscopy, scanning electron microscopy, and X-ray diffraction. The amount of palladium in the composite was 16.5 wt % as measured via thermogravimetric analysis. Thin strips of the CNT-Pd sheets were assembled as chemiresistor sensors and tested for hydrogen gas detection. The sensors demonstrated a limit of detection of 0.1 mol % and displayed signal reversibility without the need for oxygen removal or heat treatment. A decrease in signal reversibility was observed after multiple exposure cycles; however, redensification with ethanol significantly restored the original reversibility. The sensor showed the Freundlich adsorption isotherm behavior when exposed to hydrogen. The material's potential application toward a wearable, flexible sensor was demonstrated by integrating the chemiresistor onto a fabric material using hot-press processing and testing the composite for hydrogen sensitivity.

Mechanical Strength Improvements of Carbon Nanotube Threads through Epoxy Cross-Linking.

Individual Carbon Nanotubes (CNTs) have a great mechanical strength that needs to be transferred into macroscopic fiber assemblies. One approach to improve the mechanical strength of the CNT assemblies is by creating covalent bonding among their individual CNT building blocks. Chemical cross-linking of multiwall CNTs (MWCNTs) within the fiber has significantly improved the strength of MWCNT thread. Results reported in this work show that the cross-linked thread had a tensile strength six times greater than the strength of its control counterpart, a pristine MWCNT thread (1192 MPa and 194 MPa, respectively). Additionally, electrical conductivity changes were observed, revealing 2123.40 S·cm-1 for cross-linked thread, and 3984.26 S·cm-1 for pristine CNT thread. Characterization suggests that the obtained high tensile strength is due to the cross-linking reaction of amine groups from ethylenediamine plasma-functionalized CNT with the epoxy groups of the cross-linking agent, 4,4-methylenebis(N,N-diglycidylaniline).

Polymer Coating of Carbon Nanotube Fibers for Electric Microcables.

Carbon nanotubes (CNTs) are considered the most promising candidates to replace Cu and Al in a large number of electrical, mechanical and thermal applications. Although most CNT industrial applications require macro and micro size CNT fiber assemblies, several techniques to make conducting CNT fibers, threads, yarns and ropes have been reported to this day, and improvement of their electrical and mechanical conductivity continues. Some electrical applications of these CNT conducting fibers require an insulating layer for electrical insulation and protection against mechanical tearing. Ideally, a flexible insulator such as hydrogenated nitrile butadiene rubber (HNBR) on the CNT fiber can allow fabrication of CNT coils that can be assembled into lightweight, corrosion resistant electrical motors and transformers. HNBR is a largely used commercial polymer that unlike other cable-coating polymers such as polyvinyl chloride (PVC), it provides unique continuous and uniform coating on the CNT fibers. The polymer coated/insulated CNT fibers have a 26.54 µm average diameter-which is approximately four times the diameter of a red blood cell-is produced by a simple dip-coating process. Our results confirm that HNBR in solution creates a few microns uniform insulation and mechanical protection over a CNT fiber that is used as the electrically conducting core.

ACCP white paper: Essential components of a faculty development program for pharmacy practice faculty.

Prospective, ongoing faculty development programs are important in the initial orientation and short- and long-term development of faculty in higher education. Pharmacy practice faculty are likely to benefit from a comprehensive faculty development program due to the complex nature of their positions, incomplete training in select areas, and multiple demands on their time. The need for faculty development programs is supported by the increased need for pharmacy practice faculty due to the increased number of colleges and schools of pharmacy, expanding enrollment in existing colleges and schools, and loss of existing senior faculty to retirement or other opportunities within or outside the academy. This White Paper describes a comprehensive faculty development program that is designed to enhance the satisfaction, retention, and productivity of new and existing pharmacy practice faculty. A comprehensive faculty development program will facilitate growth throughout a faculty member's career in pertinent areas. The structure of such a program includes an orientation program to provide an overview of responsibilities and abilities, a mentoring program to provide one-on-one guidance from a mentor, and a sustained faculty development program to provide targeted development based on individual and career needs. The content areas to be covered in each component include the institution (e.g., culture, structure, roles, responsibilities), student-related activities, teaching abilities, scholarship and research abilities, practice abilities and the practice site, and professional abilities (e.g., leadership, career planning, balancing responsibilities). A general framework for a comprehensive pharmacy practice faculty development program is provided to guide each college, school, department, and division in the design and delivery of a program that meets the needs and desires of the institution and its faculty.

Evaluation of dosage form information provided in pediatric drug trial reports.

This report is the first to replicate the earlier findings of Standing et al and validates the inadequacy of reporting of dosage forms used in pediatric drug trials. Journal authors should provide and journal editors should require adequate dosage form information for published reports of pediatric drug trials. We also recommend that compounding pharmacists provide detailed compounding instructions to assure that extemporaneously compounded formulations can be reliably reproduced, and that quality-control data be provided to support formulation stability. Until the problem of insufficient information is addressed, replication of many pediatric drug trials is impossible, calling into question their reliability and validity.

Oral baclofen and clonidine for treatment of spasticity in children.

Few data exist in the literature to support the use of high dosages of oral baclofen and clonidine that are frequently required to treat children with spasticity. This study was a retrospective chart review of baclofen and clonidine dosages used in children diagnosed with cerebral palsy or traumatic brain injury. The primary objective was to calculate the mean dosages of baclofen and clonidine based on the duration of spasticity postinjury. Secondary objectives included determining correlations between dosage and age, injury type, location of spasticity, comorbid seizures, or concomitant antispasticity medications. Eighty-seven children receiving baclofen and/or clonidine were included in this study. Mean dosages of 40 mg/day (n = 86) and 0.4 mg/day (n = 31) were required for baclofen and clonidine, respectively. The maximum dosage was 240 mg/day for baclofen and 3.6 mg/day for clonidine. Duration postinjury, age, and concomitant antispasticity medications were the most predictive variables for baclofen dosage as a model (r = .522; P = .000). Duration postinjury and location of spasticity were the most predictive variables for clonidine dosage as a model (r = .523; P = .000). The average dosages of baclofen and clonidine used in this population of children with cerebral palsy or traumatic brain injury were similar to those reported in the literature, with higher maximum dosages found in this investigation.

Pharmacokinetics of daptomycin in a critically ill adolescent with vancomycin-resistant enterococcal endocarditis.

Daptomycin is a lipopeptide antibiotic active against multidrug-resistant gram-positive organisms. Our search of the literature found no published pediatric pharmacokinetic data. We report the use of pharmacokinetic analysis of daptomycin in a 13-year-old boy with vancomycin-resistant Enterococcus faecium endocarditis. Pharamcokinetic parameters were found to be significantly different from published adult parameters, such as a faster elimination rate, shorter half-life, and increased clearance. These age-related differences in the pharmacokinetic profile of daptomycin have significant dosing implications. As the use of this drug for off-label indications and in pediatric populations increases, it is important for clinicians to better understand the drug's pharmacokinetic profile in these patient populations.

Clinical activities of an academic pediatric pharmacy team.

BACKGROUND: Pharmacy school faculty, residents, and students have been shown to positively impact patient care in multiple settings. However, their potential role in the care of pediatric patients has not been described. OBJECTIVE: To document the contribution of pharmacy school faculty, residents, and students to the optimization of medical care for pediatric patients. METHODS: All clinical interventions performed by faculty, residents, and students for pediatric patients seen from January through December 2002 were recorded and analyzed. The interventions were concurrently recorded using a handheld and desktop computer-based documentation system, the Pharmacist's Electronic Database for Interventions, developed by the pediatric practice team. Practice sites included general pediatrics, pediatric intensive care, neonatal intensive care, and ambulatory clinics. RESULTS: Four faculty members, 5 residents, and 44 students collected intervention data. A total of 4605 interventions were performed for 3978 patients. The most common interventions performed were drug therapy change, pharmacokinetic monitoring, drug information, and medication histories/patient education. Drug added and drug deleted were the most frequent interventions performed in the drug therapy change category. The most common indications for which interventions were made were infectious (39.6%) and respiratory (23.3%) diseases. A total of 223 adverse drug events or medication errors were prevented or detected during the study period. Errors in dosing (overdose or underdose) were the most commonly encountered adverse events. CONCLUSIONS: Pharmacy school faculty, residents, and students perform numerous clinical activities that play a significant role in the multidisciplinary care of pediatric patients.

Stability of two concentrations of tiagabine in an extemporaneously compounded suspension.

The short-term stability of two different concentrations of extemporaneously compounded tiagabine suspensions was studied. Six bottles each of 6-mg/mL and 2-mg/mL suspensions were compounded using commercially available 16-mg tiagabine tablets in a 1:1 mixture of Ora-Sweet and Ora-Plus. For each concentration, three bottles were stored in the dark in a stability chamber at 23 to 25 deg C, and three were stored in the dark in a refrigerator at 3 to 5 deg C, for 61 days. The stability of tiagabine in each of the concentrations and environmental conditions was determined after preparation and at 7, 14, 28, 42, and 61 days by means of a high-performance liquid chromatographic method, which involved a reverse-phase column, a gradient mobile phase containing acetonitrile and aqueous phosphoric acid at a flow rate of 2.75mL/minute. Detection was carried out by an ultravioldet spetrophotometer at 254 nm. The drug tiagabine, the internal standard (propylparaben) and degradant eluted at 8.4, 8.6, and 9.9 minutes, respectively. The high-performance liquid chromatographic validation involved limit of detection, limit of quantitation, accuracy and precision and interday and intraday variation. There was no appearance of degradation products in eiher concentration at any time. The suspensions stored at 23 to 25 deg C became slightly discolord after day 30 , turning slightly gray from blue. However, this change could not be attributed to tiagabine degradation. The refrigerated suspensions were found to be stable (retention of 90% potency) up to 40 days. The 6-mg/mL suspensions were stable up to the study period of 61 days; however, the 2-mg/mL suspension at 3 to 5 deg C showed a potency of 87.7% on day 61 of the study. Extemporaneously compounded liquid oral preparations of tiagabine 6mg/mL in a 1:1 mixture of Ora-Plus and Ora-Sweet were stable for 61 days at 23 to 25 deg C and 3 to 5 deg C. The extemporaneously compounded liquid oral preparations of tiagabine 2mg/mL in a 1:1 mixture of Ora-Plus and Ora-Sweet were stable for 61 days at 23 to 25 deg C and for 40 days at 3 to 5 deg C.