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In this paper, we use a fluid model to describe the dynamics of the conduction electrons of multiwall carbon nanotubes. A 3-D integral formulation of Maxwell's equations is used and numerically solved with a finite-elements approach based on div- conforming basis functions. The null-piny decomposition is used to avoid the low-frequency breakdown. Index Terms--Multiwall carbon nanotubes (MWCNs), surface integral equations.

A three-dimensional full-wave surface integral formulation is used to predict the terminal response of unshielded twisted pairs. The proposed approach allows taking into account the skin effect, proximity effect and radiation losses. The proposed full-wave simulation is validated by comparing the results with those obtained by a software tool based on the finite integration technique, discussing advantages and limitations. The surface integral formulation results obtained on a short length of the line are used to predict the behavior of a longer line. In addition, they are used to extract equivalent circuits suitable for the time domain analysis by any commercial circuit simulator. Index Terms--Integral equations, nonuniform transmission lines, numerical analysis, unshielded twisted pairs (UTPs).

In this paper, we use an integral formulation of the Maxwell's equations (magneto-quasi-static limit) in the presence of superconductors to analyze a resistive joint for cables of interest for controlled thermonuclear fusion. Index Terms--Edge elements, integral equations, superconducting cable joints, superconducting magnets.

This paper shows that a Preisach engine, based on the classical Preisach model of hysteresis and identified using the Everett integrals and the first-order reversal curves, can be used whatever the orientation of the hysteresis loop [counterclockwise or clockwise] and whatever the monotonicity of the branches (increasing/decreasing). This is important for the use of the Preisach model in many innovative applications, such as hysteresis compensators in magnetostrictive devices and lithium-iron-phosphate rechargeable battery, as both the applications are characterized by clockwise hysteresis loops and strictly increasing loop branches. Numerical simulations of both cases, compared with experimental data, prove the validity of the approach. [ABSTRACT FROM AUTHOR]

Objective: Acute burns suffered from contact with environmentally heated roadways and walkways are a rare entity. The aim of this report is to assess the information gained from the treatment of a series of patients. Method: A retrospective review of a consecutive series of cases, where operative treatment was necessary, that occurred during July 2010 in southern Arizona. Results: Seven patients were included, with an average total body surface area burn of 10.2%. Direct fascial excision and tangential excision were carried out on three and four patients, respectively. Although tangential excision was carried out to normal endpoints, there was commonly a need for repetitive debridement. The total hospital costs were over $4,400,000 (£2,730,000). Conclusion: Burns suffered from contact with roadways/walkways are often deeper than suggested by their appearance. Direct fascial excision minimises the number of debridement sessions. We hypothesise that the failure to offload pressure on these wounds may be a causative factor in their observed deepening. [ABSTRACT FROM AUTHOR]

Major advances in the field of carrier-mediated agents (CMAs) have revolutionized drug delivery capabilities over the past decade. While providing numerous advantages over their small-molecule counterparts (solubility, duration of exposure, and delivery to the site of action are higher), these agents display substantial variability in systemic clearance (CL) and distribution, tumor delivery, and pharmacologic effects. This review provides an overview of factors that affect the pharmacokinetics (PK) and pharmacodynamics (PD) of CMAs in preclinical models and patients. [ABSTRACT FROM AUTHOR]

The paper aims to provide a more accurate analysis of a magnetostrictive energy harvesting device by proposing a FEM model which, assuming a realistic nonlinear characteristic of the material, is able to describe the harvesting phenomena in presence of the eddy currents induced by the Villari effect. The study is focused on the investigation of the influence of those parameters, such as pre-stress and bias, on the field dynamics and, consequently, on the eddy currents loss phenomena which cannot be disregarded if a reliable prediction of the global performances of these devices is required. The numerical results are computed by considering a compressive stress-driven vibration source and show spatial profiles of the fields, losses, and recovered powers in different operating conditions. Comparisons with the linear model are also provided. [ABSTRACT FROM PUBLISHER]

The paper presents a generalized transmission line model able to describe the high-frequency mixed-mode propagation along electrical interconnects. The model is derived from a full-wave formulation and extends the validity of the standard transmission line (TL) model to frequency ranges where the propagation is no longer of transmission electron microscopy (TEM)-type. This generalized TL model describes the high-frequency differential and common mode propagation and the mode conversion. Within its validity limits, the proposed model provides solutions in good agreement with those obtained through full-wave models. Case studies are carried out to evaluate the high-frequency mode conversion in asymmetric interconnects. [ABSTRACT FROM AUTHOR]

Background: Topotecan is a topoisomerase I inhibitor with activity against xenografts of childhood solid tumors and established clinical activity against neuroblastoma and rhabdomyosarcoma. We have studied the relationship between systemic exposure to and the antitumor activity of topotecan lactone (the active form of the drug) in the xenograft models. Furthermore, we determined whether the responses seen in these models occur at systemic exposure levels that are tolerable in children.Methods: Neuroblastoma xenografts derived from the tumors of six different patients were established subcutaneously in immune-deprived mice. Topotecan was administered by intravenous bolus injection 5 days a week for 2 consecutive weeks, repeated every 21 days for three cycles. The minimum daily doses that induced complete responses (CRs) and partial responses (PRs) were determined. Topotecan lactone pharmacokinetic studies were performed in both tumor-bearing and nontumor-bearing mice.Results: The minimum doses associated with CRs and PRs in four of the six neuroblastoma xenografts were 0.61 and 0.36 mg/kg body weight, respectively. The topotecan lactone single-day systemic exposures associated with these doses were 88 and 52 ng x hr/mL, respectively. There was an approximately sixfold difference in topotecan lactone systemic exposure (290 ng x hr/mL versus 52 ng x hr/mL) associated with achieving CRs in the least-sensitive and most-sensitive tumors, respectively.Conclusions: Neuroblastoma xenografts are highly sensitive to topotecan therapy, and responses in mice are achieved at systemic exposures similar to those that are clinically effective and tolerable in children. These results support the concept of deriving preclinical data relating systemic exposure to antitumor activity in xenograft models. Such data may be valuable in making informed decisions regarding the clinical development of new agents. [ABSTRACT FROM AUTHOR]

The present study was conducted to quantitate the disposition of irinotecan lactone and its active metabolite SN-38 lactone in mice following oral and intravenous administration, and to evaluate the systemic exposure of irinotecan lactone and SN-38 lactone associated with antitumor doses of irinotecan lactone in mice bearing human tumor xenografts. Nontumor-bearing mice were given a single oral or intravenous irinotecan dose (5, 10, 40, or 75 mg/kg), and serial plasma samples were subsequently obtained. Irinotecan and SN-38 lactone plasma concentrations were measured using an isocratic HPLC assay with fluorescence detection. The disposition of intravenous irinotecan lactone was modeled using a two-compartment pharmacokinetic model, and the disposition of oral irinotecan and SN-38 lactone was modeled with noncompartmental methods. Irinotecan lactone showed biphasic plasma disposition following intravenous dosing with a terminal half-life ranging between 1.1 to 3 h. Irinotecan lactone disposition was linear at lower doses (5 and 10 mg/kg), but at 40 mg/kg irinotecan lactone clearance decreased and a nonlinear increase in irinotecan lactone AUC was observed. The steady-state volume of distribution ranged from 19.1 to 48.1 l/m2. After oral dosing, peak irinotecan and SN-38 lactone concentrations occurred within 1 h, and the irinotecan lactone bioavailability was 0.12 at 10 mg/kg and 0.21 at 40 mg/kg. The percent unbound SN-38 lactone in murine plasma at 1000 ng/ml was 3.4 +/- 0.67%, whereas at 100 ng/ml the percent unbound was 1.18 +/- 0.14%. Irinotecan and SN-38 lactone AUCs in micebearing human neuroblastoma xenografts were greater than in nontumor-bearing animals. Systemic exposure to unbound SN-38 lactone in nontumor-bearing animals after a single oral irinotecan dose of 40, 10, and 5 mg/kg was 28.3, 8.6, and 2.9 ng h/ml, respectively. Data from the present study provide important information for the design of phase I studies of oral irinotecan. [ABSTRACT FROM AUTHOR]

A review of 122 patients treated for pancreatic adenocarcinoma from January 1978 through December 1984 was accomplished to determine patient survival and the effect of surgical palliation. One hundred patients underwent laparotomy, including biopsy only (n = 42), biliary bypass (n = 30), gastric bypass (n = 1), biliary and gastric bypass (n = 14), and curative resection (n = 13). Total patient median survival was 3.6 months and no patient lived 5 years. No significant difference in survival was found between the biliary bypass and combined biliary-gastric bypass groups. Only 1 of 30 patients (3.3%) undergoing biliary bypass alone without evidence of pre-operative gastric outlet obstruction developed late gastric outlet obstruction requiring gastrojejunostomy. Operative time and postoperative morbidity were greater in the biliary-gastric bypass group. These results do not support routine prophylactic use of gastrojejunostomy at the time of biliary bypass for patients with unresectable carcinoma of the pancreas. [ABSTRACT FROM PUBLISHER]